DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
   CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
      NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
           DIVISION OF PROCESS CONTROL ENGINEERING
            DIVISION OF ECONOMIC EFFECTS RESEARCH


CONTROL  OF  ATMOSPHERIC  EMISSIONS

   IN  THE WOOD  PULPING  INDUSTRY
        FINAL REPORT

    CONTRACT NO. CPA 22-69-18

       MARCH 15, 1970
     VOLUME
                                             V


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CONTRACTORS:
                     Environmental Engineering, !BC.
                     2324 S. W.  34th Street
                     Gainesville,  Florida 32S01

                     j.  E. Sirrine Company
                     P. 0. Box S4SS
                     Greenville, South Carolina 29608

SUB-CONTRACTORS:
                     Reynolds,  Smith and Hills
                     P. 0. Box  4156
                     Jacksonville, Florida 32201

                     PolyCon Corporation
                     185 Arch Street
                     Ramsey, (few Jersey 07445

CONSULTANT:
                     Professor  Donald F. Adams
                     Washington State University
                     Pullman, Washington 99163

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                    ERRATA  SHEET
/\ SHOULD BE 1	I IN REFERENCE FIGURE 2-2 ENTITLED




"REGIONAL DISTRIBUTION OF SULFITE AND NSSC PULP MILLS




IN THE U.S."
SULFITE MILL SHOWN IN WESTERN NORTH CAROLINA SHOULD
BE NSSC.

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       DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
   CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
       NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
             DIVISION OF PROCESS CONTROL ENGINEERING
              DIVISION OF ECONOMIC EFFECTS RESEARCH


CONTROL  OF ATMOSPHERIC  EMISSIONS

   IN  THE WOOD  PULPING  INDUSTRY
         FINAL REPORT                      by

    CONTRACT NO. CPA 22-69-18          E R Hendrickson, Ph. D., P. E.,
        MARCH 15, 1970                 Principal Investigator
     VOLUME  1
J. E. Roberson, M. S., P. E.,
 Sirrine Project Manager

J. B. Koogler, Ph. D., P. E.,
  EEI Project Manager
           ENVIRONMENTAL ENGINEERING, INC., GAINESVILLE, FLORIDA

            J. E. SIRRINE COMPANY, GREENVILLE, SOUTH CAROLINA

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SYSTEMS ANALYSIS STUDY OF EMISSIONS                      ENVIRONMENTAL ENGINEERING, INC.
CONTROL IN THE WOOD  PULP INDUSTRY                      J.  E.  SIRRINE   COMPANY
CONSULTANTS   Professor Donald F. Adams   Poly Con, Inc.                      Gainesville, Florida  Greenville, South Carolina
                                         15 March  1970
               Mr. W. Gene Tucker
               Division of Process Control Engineering
               National Air Pollution Control Administration
               5710 Wooster Pike
               Cincinnati, Ohio  45227

               Mr. F. L. Bunyard
               Division of Economic Effects Research
               National Air Pollution Control Administration
               1033 Wade Avenue
               Raleigh, North Carolina  27605

               Re:  Final Report, Contract No. CPA 22-69-18

               Gentlemen:

                     Fulfilling the requirements  of Contract No CPA-22-69-18,
               we have prepared for NAPCA 200 copies of the final report en-
               titled "Control of Atmospheric Emissions in the Wood Pulping
               Industry."  For ease in handling,  the report has been bound in
               three volumes.  Each chapter is headed by a separator sheet
               which contains the complete table  of contents for that chapter,
               and in addition each volume contains a table of contents for
               all three volumes.

                     In accordance with your letter of 21 February 1970, we
               are shipping 125 copies of the complete report to Cincinnati
               and 75 copies to Raleigh.

                     It has been a pleasure serving NAPCA and the cause of
               cleaner air. in fulfilling this contract.

                                                   Sincerely yours,
                                                   E.  R.  Hendrickson, Ph.D., P.E.
                                                   Principal Investigator
               ERH/gea
                                                 2324 S. W. 34th Street . Gainesville, Florida 32601 . 904/372-3318

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                           ABSTRACT

The basic objectives of this study were to make a comprehensive
and systematic evaluation of the technical and economic problems
involved in the control of airborne emissions, especially particu-
lates and gaseous sulfur compounds  from the chemical wood pulping
industry; and to determine the technological gaps that need to be
filled by accelerated research and development.

Included in the scope of the work were major variations of the
kraft, sulfite, and semichemical pulping processes; the nature
and sources of emissions from each process; a review of control
hardware capabilities, efficiencies, and costs; a review of
source and ambient air sampling and analysis techniques; and an
evaluation of the overall economic impacts of air quality improve-
ment in the industry.

It is felt that several major gaps in technology have been
identified which will need to be filled before any further
great steps in progress can be taken.  Brief statements of
these needed areas of research of highest priority are as
follows:

1.  Develop and standardize methods and instruments for
    monitoring emissions and ambient air.

2.  Assess the effect of operating variables on emissions
    from the kraft pulping and recovery systems.

3.  Develop and standardize organoleptic techniques for
    determinations of process emissions and evaluation of
    ambient air quality.

4.  Investigate new pulping methods which eliminate the
    use of sulfur.

5.  Define the mechanisms, with emphasis on transport
    processes and emission interactions, which will relate
    emission limitations to ambient air objectives.

6.  Evaluate emissions from sources in sulfite and NSSC
    mills and determine operating variables which affect
    emissions.
                               v

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7.  Investigate adsorption and absorption of odorous gases
    and reuse of the collected material in process.

8.  Determine whether TR3 is an effective measure of the
    acceptability of odorous emissions from kraft mills or
    must the compounds be identified more definitively.

These brief statements of needs are defined more completely and
specific projects identified.
                              VI

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                  ACKNOWLEDGMENTS
     In a project of this magnitude, there are many people
other than those designated as the authors who have made
significant contributions to the Final Report.

     In Environmental Engineering, Inc.,  Mr.  Kent Withington
assembled the necessary information and prepared the first drafts
of the chapter on emissions.  Dr. David T. Knuth and Mr. John Dollar
assisted with the literature search on on-going research.  At
Reynolds, Smith and Hills, Mr. Lamar Russell  was originally the
project engineer, but was succeeded by Mr. Leroy Doughty about the
mid-point in the project.  Mr. Doughty was assisted by Mr. Robert
Clark in collecting the information about current expenditures by
the industry.  Mr. Robert Clark, Mr. Forrest  Dryden, and Mr. Malcolm
Steeves investigated sulfur recovery from power boilers and prepared
the drafts of that chapter.  All RSH and  EEI  personnel participated
in the selection of a plan for projecting investment and operating
costs.  Mr. Doughty of RSH was primarily  responsible for this
section working with Dr. James Heaney of  EEI  who was responsible for
the modeling.

     From the Sirrine organization, Mr. Robert Farrell prepared the
power plant energy balances assisted by Mr. H. J. Steigler.  Mr.
Carlton Ranew and Mr. Peter Gombola prepared  the flow diagrams
assisted by Mr. J. Don Lee, Mr. S. L. McCluskey, and Mr. J. D. Rushton.
Mr. Wells Meakin conducted the survey and prepared the preliminary
drafts on which Chapter 2 is based.  Contributions to Chapters 5,  6,
and 7 were made by the EEI personnel cited above and the following
Sirrine personnel:  Mr. J. H. Bringhurst, Mr. W. L. Carpenter, Mr.
M. C. Freeland, Mr. P. P. Gombola, Mr. E. C.  Hartney, Mr. C. E.
Hatch, Jr., Mr. J. Don Lee, and Mr. R. C. Ranew, Mr. J. E. Roberson,
Mr. J. D. Rushton, Mr. H. A. Stokes, Mr.  J. W. Stubblefield, Jr.,
and Mr. D. B. Wilson.

     Consultants to the contractors included  Poly Con, Incorporated,
of Ramsey, New Jersey.  Mr. Jorgen Hedenhag and Mr. Samuel Jacobson
prepared much of the background information on control equipment used
in Chapters 5 and 6 and the basic cost data on control equipment used
throughout the report.

     Another consultant was Professor Donald  Adams of Washington
State University who prepared the material used in the chapter on
sampling and analysis.

     The guidance and assistance provided by  the two project officers,
Mr. W. Gene Tucker of the Division of Process Control Engineering, and
Mr. Frank Bunyard of the Division of Economic Effects Research, National

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Air Pollution Control Administration/ is gratefully acknow-
ledged.  Mr. Tucker and Mr. Bunyard were able to furnish
information which was not readily available from other sources.
Both were of special help in polishing up the many drafts
which led to the Final Report.

     Liaison was maintained throughout the project with a
committee drawn from the chemical wood pulping industry.  These
gentlemen contributed information to the contractors including
otherwise unavailable cost data.  Members of the pulp industry
Liaison Committee to whom great thanks are due include Dr. Herman
Amberg of Crown-Zellerbach; Mr. Richard Billings of Kimberly-
Clark; Mr. Russell Blosser and Dr. Isaiah Gellman of National
Council for Air and Stream Improvement; Dr. Loren Forman, Scott
Paper Company (Dr. Nicholas Lardieri, alternate); Mr. Matthew
Gould of Georgia Pacific; Dr. Glenn Kimble of Union Camp; Mr.
G. J. Kneeland, St. Regis; Mr. George Marsh of U. S. Plywood-
Champion; Mr. John McClintock of Weyerhaeuser; Dr. Samuel
McKibbins of Continental Can; Mr. George Rand of International;
Mr. J. T. Walker of Westvaco  (Mr. Bill Wassmer, alternate);
Mr. Peter Wrist of Mead  (Mr. Virgil Minch, alternate).

     The typing of the many drafts and the plates for the Final
Report was done by Mrs. Peggy Bowman, Mrs. Mary Ann Hester, Mrs.
Lala Scouten, and Miss Ann Smith.
                                  Vlll

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                        PREFACE
          This report was prepared for the National Air Pollution
Control Administration to assist in carrying out their responsi-
bilities under the Air Quality Act of 1967.  Consideration was
given mainly to the needs of the Division of Process Control Engi-
neering and the Division of Economic Effects Research.  It is
probable that the information also will be used by others including
persons in the chemical wood pulping industry.

          The intention was to provide a report which essentially
would specify the present status of emissions control in the industry,
indicate what additional progress could be expected by application of
existing or nearly-developed technology, and define areas of research
and development necessary for further advances in the future.

          As much background explanatory material as possible was
provided.  It is not necessary to be intimately familiar with the
technical aspects and economics of the industry.  However, use of
the report presupposes technical knowledge of the processes used by
the industry and an appreciation of emission control technology.

          It is important that the report be considered in its
entirety.  It was impossible adequately to qualify all discussions
and conclusions at the place the information appears in the report.
Thus, erroneous conclusions may be drawn by taking material out of
context without a proper understanding of the background.

          Costs used in the engineering estimates and calculations
were based on the price of supplies and equipment as of January
1969.  Statistical data on the industry were verified as of
December 1968.
                            IX

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                   GENERAL TABLE OF CONTENTS

         A Detailed Table of Contents  for Each Chapter
           Will Be Found on the Separator Sheet
                    Preceding Each Chapter
                           VOLUME I

                                                            Page  No.

Letter of Transmittal                                        iii

Abstract                                                     v

Acknowledgements                                             vii

Preface                                                      ix


Chapter 1 - INTRODUCTION

   Air Quality Act of 1967                                   1-1

   General Description of Industry Studies                   1-1

   Objectives of This Study                                  1-2

   Procedures for the Study                                  1-2


Chapter  2 - THE CHEMICAL WOOD PULPING INDUSTRY

   Summary                                                   2-1

   Introduction                                              2-2

   Economic Position                                         2-4

   Present Geographic Distribution                           2-6

   Forecasts                                                 2-9

   References                                                2-14
                              XI

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                                                          Page No.

Chapter 3 - PRESENT PULPING PRACTICES

   Summary                                                 3_1

   Introduction                                            3_2

   Kraft Pulping                                           3-12

   NSSC Pulping                                            3-54

   Sulfite Pulping                                         3-62


Chapter 4 - QUANTITY AND NATURE OF EMISSIONS

   Summary                                                 4_1

   Introduction                                            4_2

   Kraft Gaseous Emissions                                 4_4

   Kraft Particulate Emissions                             4-44

   NSSC Emissions                                          4-49

   Sulfite Emissions                                       4-53

   Auxiliary Furnace Emissions                             4-59

   References                                              4-66


Appendix A - Summary Data for Chapter 2


                           VOLUME II

Chapter 5 - CONTROL METHODS PRESENTLY IN USE

   Summary                                                 5-1

   Introduction                        ""                   5-3

   General Description of Control Equipment                5-4

   Application, Cost,  and Effectiveness of Present
     Control Methods                                       5-25
                              xn

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                                                          Page No,

       Kraft Sources                                       5-33

       Sulfite Sources                                     5-151

       NSSC Sources                                        5-156

   References                                              5-157


Chapter 6 - NEW DEVELOPMENTS IN CONTROL TECHNOLOGY

   Summary                                                 5_1

   Introduction                                            5_2

   General Description of Control Methods                  6_2

   Application, Cost, and Effectiveness of New
     Control Methods                                       6-10

       Kraft Sources                                       6-10

       Sulfite Sources                                     6-40

       NSSC Sources                                        6-42

   References                                              6-45


Chapter 7 - CRITICAL REVIEW OF CONTROL TECHNOLOGY

   Summary                                                 7_1

   Introduction                                            7_2

   Kraft Process                                           7_3

   Sulfite Process                                         7-18

   NSSC Process                                            7-21


Chapter 8 - POWER BOILER SULFUR RECOVERY

   Summary                                                 8-1

   Introduction                     ,                       g_2

   Flue Gas Desulfurization Technology                     8-19
                             Kill

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                                                           Page No.

   Process Feasibility Considerations                       8-32

   R & D Efforts                                            8-38

   References                                               8-39


Appendix B - Summary Data for Chapter 8


                          VOLUME III

Chapter 9 - SAMPLING AND ANALYTICAL TECHNIQUES

   Summary                                                  9-1

   Introduction                                             9-2

   Kraft Sources                                            9-4

   Sulfite Sources                                          9-65

   NSSC Sources                                             9-76

   References                                               9-77


Chapter 10 - ON-GOING RESEARCH RELATED TO REDUCTION
             OF EMISSIONS

   Summary                                                  10-1

   Introduction                                             10-2

   Emissions Control Technology                             10-2

   Cost and Effectiveness of Emission Control               10-39

   Sampling and Analytical Techniques                       10-40

   Control Equipment Development                            10-50

   Process Changes Affecting Emissions                      10-54

   Chemistry of Pollutant Formation or Interactions         10-57

   New Pulping Processes                                     10-68

   Control Systems Development                              10-72
                              xiv

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                                                           Page  No.

Chapter 11 - RESEARCH AND DEVELOPMENT RECOMMENDATIONS

   Summary                                                  11-1

   Areas of Needed Research                                 11-2

   Specific R S D Projects                                  11-6

       Emission Control Technology                          11-6

       Cost and Effectiveness of Emission Control           11-8

       Sampling and Analytical Techniques                   11-9

       Control Equipment Development                        11-10

       Process Changes                                      11-10

       Chemistry of Pollutant Formation or Interaction      11-11

       New Pulping Processes                                11-12

       Control System Development                           11-12

       Other                                                11-12


Chapter 12 - CURRENT INDUSTRY INVESTMENT AND OPERATING
             COSTS

   Summary                                                  12-1

   Introduction                                             12-2

   Incremental Cost Categories                              12-7


Chapter 13 - FUTURE INDUSTRY INVESTMENT AND OPERATING
             COSTS

   Summary                                                  13-1

   Introduction                                             13-2

   Concepts for a Management Model                          13-2
                              xv

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                                                         Page No.




Analysis of Emission Sources and Controls                 13-9




Assignment of Costs                                       13-33




Trends in Future Capital Expenditures                     13-40




References                                                13-49
                          xvi

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                          CHAPTER  1




                          TABLE OF CONTENTS






                                                          Page No.



Air Quality Act of 1967                                      1-1




Special Industry Studies                                     1-1




Objectives of the Study                                      1-2




Procedures for the Study                                     1-2

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                               CHAPTER  1


                                 INTRODUCTION

1.1  THE AIR QUALITY ACT OF 1967

     The Air Quality Act of 1967 builds upon the basic precepts  of
     the Clean Air Act of 1963 to develop a technically sound and
     rational plan for improvement of air quality through application
     of air quality criteria and detailed control technology. This
     would be accomplished on a regional basis by a cooperative  effort
     on the part of the states and the Federal government.   Key  items
     in the abatement program would include designation of air quality
     control regions, publication of air quality criteria, publication
     of information on available control technology, development of
     air quality standards, and development of implementation plans
     to meet the standards.

     The basic responsibility of the National Air Pollution Control
     Administration for research and development into the causes,
     effects, extent, prevention, and control of air pollution was
     expanded.  This was necessary to provide an improved techno-
     logical basis for the total program.  Research and the identi-
     fication of needed research were recognized as the key to
     effective air quality improvement.  In addition, Congress
     expressed concern regarding the economic impact of implementing
     the legislation.  They directed that specific economic studies
     be undertaken and a special report made on the costs to all
     segments of the economy of carrying out the provisions of the
     law.

     The Air Quality Act retained many of the provisions of the  Clean
     Air Act and, in addition, has many important provisions not
     reported here.  The revisions described above, however, are
     the major ones which have a bearing on the need for this study.


1.2  SPECIAL INDUSTRY STUDIES

     Some of the largest manufacturing industries have some of
     the most complex air quality control problems.  Because of
     their technical orientation, the industries have been successful
     in developing new technology for solving their problems,  In
     addition, the technology which they have developed may be
                                       1-1

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      applicable to control of other sources.  The Air Quality Act
      imposed on NAPCA the responsibility of becoming familiar with
      the technology of air pollution control, developing control
      technology documents to accompany air quality criteria documents,
      identifying areas of research essential to progress in carry-
      ing out the provisions of the act, and assessing the economic
      impact of implementing the legislation.  To carry out some of
      these responsibilities, the Division of Process Control
      Engineering and the Division of Economic Effects Research
      jointly planned and are conducting under contract, a series
      of systems analysis studies of emissions control in major
      industries.  The study being reported is concerned with the
      control of atmospheric emissions in the chemical wood pulping
      industry.
1.3  OBJECTIVES OF THE STUDY

     The purpose of this study was to make a comprehensive and
     systematic evaluation of the technical and economic problems
     involved in the control of airborne emissions, especially
     particulates and gaseous sulfur compounds from the wood pulping
     industry; and to determine the technological gaps that need to
     be filled by accelerated research and development.  Included
     in the scope of the project were a consideration of major
     variations of the kraft, sulfite, and semichemical pulping
     processes; the nature and sources of emissions from each
     process; a review of source and ambient air sampling and
     analysis techniques; a review of control hardware capabilities,
     efficiencies, and costs; and an evaluation of the overall
     economic impacts of air quality improvement in this industry.
1.4  PROCEDURES FOR THE STUDY

     The first phase of the project was concerned essentially
     with compiling and presenting both statistical and technical
     data about the chemical wood pulping industry.  Information
     was gathered on the locations, types, and capacities of all
     chemical pulp mills in the United States.  Projections of the
     data were made through 1980 in an attempt to present a picture
     of increases in capacity as well as changes in regional
     distribution and predominant pulping processes of the industry.
                                       1-2

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Surveys and critical reviews were made of ongoing research which
is related to control of atmospheric emissions and of techniques
used in the industry to monitor emissions.   A major effort in
this phase was devoted to defining typical pulping processes
(flow diagrams)  and preparing appropriate heat and materials
balances including identification of emissions.   Confirmation
of the data developed during this phase was obtained by actual
visits to selected operating mills in various parts of the
country which had processes similar to the theoretical flow
diagrams.

A second phase involved a feasibility analysis of emissions
control technology in the industry.  By appropriate modelling
based on confirmed flow diagrams, the cost and effectiveness
of emission control were evaluated for individual sources and
for entire pulping processes.  New foreign and domestic develop-
ments were considered in addition to current U.  S. practices.
The feasibility of sulfur recovery from utility boilers also
was investigated.

Based upon all of the preceding work, gaps in technology
were identified and recommendations made as to needed research
and development efforts.  The recommendations include, but
are not limited to, the following areas:

1.  The need for further development of, or clarification
    of effectiveness and cost of current control technology,

2.  The necessity of developing new sampling and analytical
    techniques,

3.  The necessity of research and development in new control
    technology,  and

4.  Modification of current pulping processes or the
    development of new processes that could lead to
    reduced atmospheric emissions.

The final phase  of the work was an economic study of emission
control in the pulping industry.  A model was developed which
utilizing the information gathered in previous phases made
possible an estimation of the capital cost and annual operating
and maintenance costs of pollution control equipment now in
operation in the industry.  A projection model was developed
to provide the capability of projecting expenditures for
achieving desired levels of emission control  for a reasonable
time into the future.
                                  1-3

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                          CHAPTER  2



                  THE CHEMICAL WOOD PULPING INDUSTRY






                           TABLE OP CONTENTS
Summary




Introduction




Economic Position




Present Geographic Distribution




Forecasts




      Growth and Process Trends




      Geographic Distribution Trends




References
Page No,




  2-1




  2-2




  2-4




  2-6




  2-9




  2-9




  2-12




  2-14
                            2-i

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                          CHAPTER  2

                  THE CHEMICAL WOOD PULPING INDUSTRY



                               SUMMARY
      The pulp and paper industry is the ninth largest in the
United States, accounting for nearly four percent of the value
of all manufacturing.  The per capita consumption of paper is
expected to continue to rise from the late 1969 value of 550
pounds per year.

      The United States and Canada produce more than 52 percent
of the world's supply of pulp, with the U. S.  in 1968 furnishing
nearly 38 million short tons.  Of this amount, 32 million tons
were chemical pulp.  Approximately 75 percent of this was pro-
duced by the kraft process, 9 percent by the sulfite, and 10
percent by neutral sulfite semichemical.  The U. S. industry
includes more than 360 pulp mills of all types, mechanical and
chemical.

      This study is concerned mainly with three types of chemical
pulping processes; kraft, sulfite, and NSSC.  The geographical
distribution of the industry as of December 1968 by process and
size is shown in the chapter by maps and in Appendix A by tables.

      Projections have been made of chemical pulp production by
process and region of the country through 1985.  The production
of soda and dissolving pulps is expected to remain reasonably
constant.  Sulfite pulp production will probably decrease slightly.
It is anticipated that NSSC production will nearly double and kraft
increase to approximately two and one-half times the 1968 figures.

      By 1985, kraft and NSSC are projected to dominate chemical
pulping in the U. S. with kraft accounting for 85 percent and NSSC
9 percent of total chemical pulp production.  The total production
of chemical pulp is expected to slightly more than double over the
1968 figures.

      Regional distribution of pulping capacity is expected to
remain in the same relative proportions as it is today.
                              2-1

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2.1  INTRODUCTION

     The pulp and paper industry is the ninth largest manufacturing
     industry in the United States.  This industry accounts for
     nearly four percent of the value of all manufacturing.

     Although paper is one of the oldest manufacturing industries,
     it is an industry that is expanding faster than the general
     economy.  Consumption of paper rises with increased affluence.
     The per capita consumption of paper in the U. S. is now about
     550 pounds per year compared to about 412 pounds only ten years
     ago.  There are no signs that per capita consumption is leveling
     off.

     The pulp and paper industry is comprised of three distinct
     segments:  (1)  pulp,  (2)  primary paper and paperboard (cardboard,
     et cetera), and (3)  converted paper and paperboard products.

     PulpMost pulp is made by integrated companies and consumed
     captively without moving through the marketplace.  About ten
     percent of the total  pulp produced is,  however, made by inde-
     pendent pulp producers without their own paper making facilities
     or by integrated companies producing surpluses for market.
     About three percent of all pulp produced is consumed outside
     the industry for such products as cellophane, rayon,  cellulose
     esters and ethers, and their derivatives.   Eighty percent of
     the pulp used for making paper comes from wood;  about 20 percent
     of the pulp is  made from waste paper or such fibers as cotton and
     bagasse.

     Primary Paper and PaperboardThis  segment of the industry produces
     paper,  paperboard,  and building paper and board.   A portion of this
     production is sold directly to industrial users such as  newspapers,
     book publishers,  and  printers,  or to building and other  users.

     Converted Paper and Paperboard ProductsAbout 70 percent of the
     primary paper production,  however,  is further processed  by paper
     converters into such  products  as containers,  bags,  sanitary tissue
     products,  and stationery.

     Wood pulp is  prepared either mechanically or chemically.   In the
     mechanical processes  (groundwood, defibrated and exploded)  wood
     is  shredded or  separated  by physical means.   In the chemical pro-
     cesses  (kraft,  sulfite, NSSC,  soda,  and dissolving) wood is treated
     with chemical reagents  which form soluble  compounds with the non-
     cellulosic materials,  thus  leaving  residual  cellulose.   The NSSC
     process  involves  treating the  wood  first with a mild  chemical and
     then mechanically separating the fibers.


                               2-2

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    Data are presented in Table 2-1..which show the number of, mills
    and total mill capacities for the five chemical pulping processes.
    In Table 2-1, all capacities are based on air dried tons of pulp;
    annual capacities are based on operating at rated capacity for
    350 days per year, allowing for normal maintenance and scheduled
    shutdowns.  It is emphasized that these figures represent pro-
    duction capability and do not portray actual production data.
                              TABLE  2-1

                              SUMMARY - U.S.A.
                CHEMICAL PULP MILL CAPACITIES (UNBLEACHED)

                           AS OF DECEMBER 31, 1968

Process
Kraft
Sulfite
NSSC
Dissolving
Soda
TOTALS
Number
of
Mills
116
43
43
8
4
214

Capacity*
ADT/Day
87,808
10,875
10,675
4,565
570
114,473
Annual
Capacity*
Tons
30,733,000
3,799,500
3,736,500
1,600,000
200,000
40,069,000
1968
.Production
Tons
24,300,000
2,500,000
3,500,000
1,500,000
200,000
32,000,000
*These figures represent capacity and not actual production.  ADT
 stands for air-dried tons of unbleached pulp per day; air-dried pulp
 contains 10 percent moisture.
                               2-3

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     Three of the chemical wood pulping processes display a potential
     to cause air pollution.   These are the kraft, sulfite, and NSSC
     processes.  Collectively, these three processes account for
     about 80 percent of the  total wood pulp produced in the United
     States.

     To define the air pollution problem posed by the chemical wood
     pulping industry, it is  necessary to establish the geographical
     distribution of existing production capacity and to identify
     trends which might cause a redistribution of production capacity
     in the future.
2.2  ECONOMIC POSITION

     The United States pulp and paper industry includes more than 360
     pulp mills of all types,  mechanical and chemical.   Estimates for
     1967 indicate 37 companies, each with pulp and paper sales at the
     manufacturer's level of at least $100 million, accounted for
     $10.24 billion in sales,  or 49 percent of the industry's total of
     $20.88 billion.

     Table 2-2 shows  the wood  pulp production in 1968 for the ten
     leading pulp producing nations of the world (I).  The other
     60 pulp producing nations individually produced less than one
     million tons of  pulp and  collectively produced 13,441,000 tons
     of pulp in 1968.  From these data,  it can be determined that
     the U. S. and Canada produced 52  percent of the world's wood
     pulp in 1968. This massive capacity, coupled with the contiguous
     features of the  U.  S. and Canada, place these countries in a
     leading position in terms of production.

     It is reported (2_)  that North American industry is planning to
     build 65 new pulp mills in the early 1970's39 in the U. S. and
     26 in Canada. It seems reasonable to conclude,  therefore, that
     the U. S. and Canada will remain the dominant nations in wood
     pulp production  at least  for the next two or three decades.
                               2-4

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                                TABLE  2-2

                          PRODUCTION OF TEN LEADING
                        PULP PRODUCING NATIONS - 1968
Nation
United States
Canada
Sweden
Japan
USSR
Finland
Mainland China
Norway
France
West Germany
Million Short Tons
37.89
16.40
7.76
7.56
6.78
6.56
2.30
2.18
1.77
1.73
Data taken from Pulp and Paper:  19th Annual World Review
                                2-5

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2.3  PRESENT GEOGRAPHIC DISTRIBUTION

     A compilation of data on current wood pulping practice in
     the U. S. was begun by searching available published reports,
     such as Lockwood's Directory of_ the Paper and Allied Trades,
     Post's Pulp and Paper Directory, and Southern Pulp and Paper
     Manufacturer's Southern Mill Directory.   Information originally
     tabulated included plant location,  owner, pulping process
     employed, rated mill capacity,  type of wood pulped, and age
     of original mill.   These data were  brought up to date based
     on in-house information and available NAPCA - NCASI reports,
     and communications with mill managers.

     The corrected data have been tabulated and are presented in
     Appendix A (Tables A-l and A-2). Using  these data as a base,
     two maps have been prepared to  illustrate geographically the
     distribution of chemical wood pulping mills throughout the
     United States.  These maps are  presented here as Figures 2-1
     and 2-2.
                               2-6

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                                                                             CLEVELAND I      PHILADELPHIA"
                                                                                    PITTSBUR6
                                                                                        A
  KRAFT  MILLS

   0-400 TPD

  400-700 TPO

  700-1000 TPD

  1000-1300 TPO

  2. -1300 TPO
                 REGION  I

                 REGION  H
                 REGION  m

                 REGION  ET
                 REGION  Z
                                            2-7
REGIONAL DISTRIBUTION
  OF KRAFT  PULP MILLS
        IN  THE U. S.
         FIGURE 2-1

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                                                                                                CLEVELAND 1      PHILADELPHIA
                                                                                                       PITTS BURG
                                                                                      INDIANAPOLIS         _^/   ^ WAEHMGT9N |
                                                                                      h *"  U   1/7   J^  X
                                                                                           ^T^f /  /.,  RICHMOND
                                                                                      f'f              /^       '
                                                                                                         ROANOKE
                                                                                                            ^  WINSTON
                                                                                                              SALEM
                                                                                                              RALEIGH
NSSC  MILLS

  0- 200 TPD
 200- 300 TPD
  >. - 300 TPO
 SULFITE  MILLS
A   0- 100 TPO
A  100-200 TPD
A  200-400 TPD
A  > -400 TPD
                          REGION  I
                          REGION  TJ
                          REGION  IE
                          REGION  I?
                          REGION  Z
                                                            2-8
     REGIONAL  DISTRIBUTION
OF SULFITE AND NSSC  PULP  MILLS
              IN  THE U.  S.
                FIGURE 2-2

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  2.4  FORECASTS

2.4.1  GROWTH AND PROCESS TRENDS

       A number of forecasts have been made which attempt to portray
       the future demand for wood pulp (all grades)  in the United
       States.  These forecasts range from a low of  61 million tons
       per year in 1985 as given by Forest Research  Report No. 17,
       1965 (3), to a high of 89 million tons per year in 1985 as
       given by Resources in America, 1963 (_4) .   A middle of the
       road forecast has been made by the American Paper Institute.
       Based on these data, plus numerous other  sources, and a.
       wealth of in-house knowledge, H.  W. Meakin of the J.  E.
       Sirrine Company has projected chemical pulp production through
       1985.  These projections are reproduced here  as Figure 2-3.
       Historical data are presented in Appendix A (Table A-3).

       Viewed together, these data show that through 1985, the
       production of soda pulp and dissolving pulps  will remain
       reasonably constant; sulfite pulp production  will decrease
       slightly; NSSC production will nearly double, and kraft
       pulp will increase to approximatley 2 1/2 times the 1968
       amount.

       In 1985,  kraft and NSSC processes are expected to dominate
       chemical pulping in the United States. Kraft production
       is projected to account for about 85 percent  of the chemical
       (about 70 percent of total wood pulp, all grades, production),
       and NSSC for about 9 percent of the total chemical pulp pro-
       duction.   The total production of chemical pulp is expected
       to slightly more than double.

       Table 2-3 has been included to summarize  announced and esti-
       mated expansion and phasing-out operations through 1980.
       Detailed  breakdowns of Table 2-3  may be found in Appendix  A
       (Tables A-4, A-5,  A-6,  and A-7).
                                2-9

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                          FIGURE  2-3



                   PROJECTION OF  PRODUCTION


                OF CHEMICAL PULPS IN THE  U. S.
     80
     70
to
z.
o
I



o

co

u_
o

CO
z.
o
60
50
    40
o
o


D-


Q
LU


O
o
o;
o.
    30
    20
    10
                                                   TOTAL
                                                   KRAFT
                                                        NSSC


                                                        SULFITE

                                                        DISSOLVING

                                                        SODA
                                                     1985
                             2-10

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                      TABLE  2-3

            ANNOUNCED AND ESTIMATED EXPANSION ,  x
           AND PHASING OUT PLANS THROUGH 1980 u;

    Current and Planned New Plant Construction as  of December 31,  1968

                                     CAPACITY APT/DAY
Kraft
5,866 (12)
2,135 (5)
Sulfite
830 (2)
0
N5SC
750 (3)
568 (2)
     New
     Expansion

     TOTAL            8,001 (17)              830 (2)    1,318 (5)
II.  Estimate of Phased Out Operations

                                    CAPACITY APT/DAY
Time Period
In 1968 (c)
In 1969-70
In 1970-80
TOTAL
Kraft
205
85
290
(1)
(1)
(2)
Sulfite
835
503
1,562
2,900
(5)
(3)
(17)
(25)
NSSC
235 (1)
235 (1)
Soda
60
140
200
(1)
(2)
(3)
     (a)   Detailed breakdowns of these data may be found in
          Appendix A-

     (b)   Figures in (  )  indicate number of mills

     (c)   These capacity figures for 1968 are not included in
          Table 2-1.
     In addition to the current and planned new plant construction
     shown above, there are at least twelve proposed or tentative
     mills in the talking stage of development.   These twelve  mills
     would, if brought to production,  supply in excess of an
     additional 3,000 tons per day of  pulp.
                           2-11

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2.4.2  GEOGRAPHIC DISTRIBUTION  TRENDS

       Table 2-4  contains  information which  shows  the  regional
       distribution of  the industry  in  1968  as well  as the  pro-
       jected distribution in 1975 and  1980,

       It appears to be the concensus of  industry  representatives
       on the Pulp Industry Liaison  Committee that the distribu-
       tion of pulp production  in the forseeable future (through
       1985)  will remain essentially as it is today.   The projected
       chemical pulp production shown on  Figure 2-3 was, therefore,
       stratified by region on  the basis  of  this assumption.

       There are  several factors which  influence the decision to
       locate a pulp mill  in a  given section of the  country.   One
       of these factors is  the  availability  of trees to serve as
       raw material.  Some  concern has been  expressed  by forestry
       management people (_5_, 6_)  that a  tightening  of the wood
       supply in  the  South  could occur  in the late 1970"s.  If
       this were  to occur,  there could possibly be a shift  of pro-
       duction to the West  and  North.   It is felt, however, that by
       more intensified management of the better forest lands and
       improved silvaculture, we can grow appreciably  more  wood and
       thus satisfy the demands of the wood pulping industry.  Thus,
       it is  predicted  that the distribution of chemical pulp pro-
       duction by regions will  remain substantially as it is  today.
                                2-12

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                          TABLE  2-4

         PROJECTION OF PULP PRODUCTION BY REGION IN THE U.  S.
                             1968 - 1980
                       1968
1975
1980
REGION
Kraft
Northeast
Northcentral
Southeast
Southcentral
Northwest
TOTAL
Sulfite
Northeast
Northcentral
Southeast
Southcentral
Northwest
TOTAL
NSSC
Northeast
Northcentral
Southeast
Southcentral
Northwest
TOTAL
Prod.
TPD

3,617
2,319
36,249
15,850
11,393
69,428

1,464
1,354
471
0
3,854
7,143

1,731
3,330
2,926
1,283
730
10,000
% Of
Indust.
Prod.

5.21
3.34
52.21
22.83
16.41
100.0

20.49
18.96
6.59
	
53.96
100.00

17.31
33.30
29.26
12.83
7.30
100.00
Prod.
TPD

5,582
3,579
55,939
24,460
17,582
107,142

1,171
1,083
377
0
3,083
5,714

2,324
4,472
3,929
1,723
980
13,428
% Growth
Over
1968

54.3
54.3
54.3
54.3
54.3
54.3

(20.0)
(20.0)
(20.0)
	
(20.0)
(20.0)

34.3
34.3
34.3
34.3
34.3
34.3
Prod.
TPD

6,981
4,476
69,962
30,592
21,989
134,000

1,171
1,083
377
0
3,083
5,714

2,720
5,233
4,598
2,016
1,147
15,714
% Growth
Over
1968

93.0
93.0
93.0
93.0
93.0
93.0

(20.0)
(20.0)
(20.0)
	
(20.0)
(20.0)

57.1
57.1
57.1
57.1
57.1
57.1
% Growtl
Over
1975

25.1
25.1
25.1
25.1
25.1
25.1

0
0
0
	
0
0

17.0
17.0
17.0
17.0
17.0
17.0
TPD stands for Tons Per Day
( )  Represents a decline in production
                            2-13

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2.5  REFERENCES

     1.   Staff, "19th Annual World Review," Pulp and Paper, 43_(7) ,  7-  ,
         (June  25,  1969).

     2.   Staff, "Expansion/Modernization/Acquisition Report," Pulp  and
         Paper, 42_(51) ,  43-  ,  (December 16, 1968).

     3.   "Timber Trends  in the United States," Forest Service, U. S.
         Department of Agriculture, Washington, 1965.

     4.   "Resources in America's Future," Landsberg, Fishman and Fisher,
         New York,  1963.

     5.   Josephson, H.R.  (Director, Division of Forest Economics and
         Marketing  Research, Forest Service, USDA), "Availability of
         Wood Supplies for the Pulp and Paper Industry," Paper presented
         at 1968 Annual  Meeting of Pulp and Raw Materials Division  of
         American Paper  Institute, New York, February 20, 1968.

     6.   Slatin,  Benjamin (Economist,API), "Future Demands for Pulp and
         Paper  as They Influence Pulp Wood Requirements," Paper presented
         at fall meeting of the Southeastern Technical Division of  the
         American Pulp Wood Association, Atlanta, November 21, 1968.
                                    2-14

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                          CHAPTER  3



                      PRESENT PULPING PRACTICES






                          TABES OF GQOTEKTS
Summary
Kraft Pulping




   Kraft Flosr Diagrams




NSSC Pulping




   NSSC Flow Diagrams




Sulfite Pulping




   STulfite Flew Diagrams
Page No.




 3-1




 3-2




 3-12




 3-13




 3-54




 3-54




 3-62




 3-63
                              3-i

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                         CHAPTER  3
                  PRESENT CHEMICAL PULPING PRACTICES
                                SUMMARY
In wood pulping, cooking chemicals have rhe function of dissolving
the lignin that bonds the cellulose fiber together.  Thus various
chemical processes have been developed, using acid, alkaline, or
neutral solutions, which delignify with as little destruction of
the cellulose as possible.  Most of the chemical pulping processes
in use today utilize sulfur in some form in the cooking liquor.
In bringing about the solution of wood components, the sulfur combines
with constituents of the wood to produce gaseous and particulate com-
pounds which may degrade the quality of air or water if discharged
into the environment

Three of the chemical processes (kraft, sulfite, and neutral sulfite
semichemical) account for approximately 80 percent of pulp production
in the U. S.  The choice of the pulping process is determined by the
product being made, by the type of wood species available, and by econo-
mic considerations.  Therefore there is not a free choice in the process
to be used.  The three processes have been identified as possible
sources of particulate and gaseous emissions into the atmosphere.  For
this reason they are the subject of this study.

To specifically illustrate the air pollution potentials of the industry,
flow diagrams representing pulping processes typical of mills produc-
ing the majority of the nation-s total pulp output were prepared.  These
simulated flow diagrams include variations of the basic kraft, sulfite,
and NSSC processes and are prepared to feature material balances and
processes or equipment which will affect the selection of air quality
control measures.  The power plant energy balances associated with
each flow diagram were also prepared to stress the air quality aspect.

Ten flow diagrams are presented for variations of the kraft process,
four for sulfite, and three for NSSC.  Except for Kraft Flow Diagram
No. 10, only ^process variations utilized by a significant number of
mills have been considered =,  With each flow diagram is presented infor-
mation on the typical age and location of the type of mill, general data
about the process arrangement and assumptions made, plus figures on
representative emissions from each source.  The flow diagrams are
hypothetical, for use in later parts of the study, and none can
be identified with a specific mill.
                               3-1

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3.1  INTRODUCTION

     Three of the chemical processes  (kraft, sulfite, and neutral
     sulfite  semichemical) account for approximately 80 percent of
     pulp production in the U. S.  The choice of the pulping pro-
     cess is  based on a variety of factors including the product
     being made,  the type of wood species available, and economic
     considerations.  Therefore, there is not a free choice in the
     process  to be used.  The three processes have been identified
     as  sources of particulate and gaseous emissions into the atmos-
     phere.   For  this reason they are the subject of this study.

     To  specifically illustrate the air pollution potentials of the
     industry, simulated flow diagrams representing pulping processes typical
     of  mills producing the majority of the nations's total pulp
     output were prepared.  These diagrams include modifications
     of  the basic kraft, sulfite, and NSSC processes and are
     prepared to feature material balances and processes or
     equipment which will affect the selection of air quality
     control measures.   The power plant energy balances associated
     with each flow diagram were also prepared to stress the
     air quality aspect.  Thus,  not all unit processes are shown
     on each flow diagram and where the emissions from two unit
    processes normally are discharged through the same vent,
     they may  be indicated as  one.

    Diagrams  were prepared to show material balances on the basis
    of one ton of unbleached air dry pulp.   Except for Kraft Flow
    Diagram No.  10,  only  process  arrangements  utilized by a significant
    number of mills  have  been considered.  Diagrams  have not been pre-
    pared for the groundwood  and soda pulping  processes because the
    former is a mechanical process with  very little  or no particulate
    or odorous emissions  and  the  latter  is  considered obsolete.  The
    flow diagrams are hypothetical  and none can  be identified with
    a specific mill.
                             3-2

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       Combination boilers  firing bark plus one or more fossil fuels
       are  common.  The  emissions from bark firing have been shown
       separately and are estimated on the basis of debarking 100
       percent of the wood  supply.   For mills receiving wood chips the
       bark flow will be reduced in proportion to the amount of chips
       received.  Therefore,  the oil and  coal consumption must be in-
       creased accordingly.   Since  the amount of bark burned varies
       considerably from mill to mill, the emission estimates from bark
       firing vary accordingly.

       Boiler emissions  for both coal and oil have been calculated
       and  are indicated on the  flow diagrams.  Only one set of these
       emissions is applicable depending  upon the particular fuel
       in use.  In NO case  should the coal and oil emissions be
       added together.

       Emissions from a  power boiler firing natural gas are not shown,
       primarily due to  lack  of  space.  The power boiler emission when
       firing natural gas is  approximately the same as fuel oil in
       terms of flue gas volume  and weight.  Of course, natural gas
       has  no SO  or particulate emission.      j

       A  sulfur content  of  two percent was selected as being a
       reasonable value  for both coal and oil and a value which can be
       easily adjusted for  any fuel analysis.  See Chapter 8 for further
       comments regarding fuel consumption and composition.
3.1.1  PURPOSE OF THIS  CHAPTER

      The purpose of this  chapter is  to show  flow diagrams and power
      plant  energy balances  in order  to identify and quantify signifi-
      cant particulate and malodorous emissions from major sources in
      the pulping processes.  In subsequent chapters, various pieces
      of emission control  equipment will be studied for these sources
      with a view to analyzing the cost of this equipment versus its
      effectiveness in reducing emissions.  The power plant  energy
      balances were developed in order to determine the emissions result-
      ing from the generation of the  steam required for process and
      electric power generation.

      The quantity and concentration  of emissions on all flow diagrams
      are based on "annual averages"  and are  not intended to be
      used for establishing  emission  standards, guides, or criteria.
                                   3-3

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3.1.2  DEFINITIONS
       The following definitions  are provided  for  the benefit of those
       not intimately familiar with the  chemical wood pulping industry.
       In some instances  definitions are given because of special
       meanings which a term may  have  in this  report.

       Particulate - Any  material which  exists as  a  solid in a gas
       stream at  duct conditions  and is  collected  in accordance with
       IGCI sampling procedures.

       Trace - A  quantitative expression of  emissions which is less
       than 0.01  pounds per ton of air dry unbleached pulp.

       Standard Conditions  - 29.92 inches of mercury and 70 degrees F.

       Sulfidity  - An expression  of the  percentage makeup of chemicals in
       kraft cooking liquor obtained by  the  formula
                               Na S
                                            x  100
                            Na S + NaOH

      where  the  sodium compounds are expressed as Na_O.

      Yield  - The percentage of a specific weight of bone dry wood that
      is  converted  to bone dry pulp.

      Weak Wash  - A liquid stream in the kraft process which results from
      washing of the lime mud.  It is used mainly for dissolving smelt.

      Smelt  - The molten chemicals from the kraft recovery furnace
      consisting mostly of sodium sulfide and sodium carbonate.

      Oxidation  Efficiency - The percentage of sodium sulfide in the kraft
      black  liquor  which is oxidized by air introduced into the liquor.
      The Na S is usually expressed in grams per liter of black liquor.
             A

      Roundwood  - Logs as delivered to the mill with bark attached and
      cut to specified lengths (up to 10 feet).

      Board  - A  heavy sheet made with single or multiple plies of pulp
      formed on  a board machine such as a fourdrinier.

      Linerboard -  A laminated container board usually made of kraft pulp.
      It consists of a base sheet which is coarse strong pulp and a top
      liner  sheet which is fine pulp.  The top liner gives the container
      board  a more  finished exposed sulface than the base sheet.
                                      3-4

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       Top Liner - A sheet, usually produced from kraft pulp, which is
       added as a laminate to the base sheet to produce linerboard.  The
       pulp may in some cases be bleached.

       Base Stock - A sheet, usually produced from unbleached kraft
       pulp, formed into linerboard on a fourdrinier machine.

       Corrugating Medium - A sheet, usually made from NSSC pulp,
       which is corrugated to form a cushioning layer  when attached
       to a single sheet or between two boards.  The corrugating
       sheet is usually 0.009 inches thick  and traditionally is
       referred to as "9 point."

       Bark Boiler - A combustion unit used to produce steam for
       process or electrical energy which is designed  to  burn mainly
       bark and wood residues.

       Combination Boiler - A combustion unit used to  produce steam
       for process or electrical energy which is designed to burn
       bark and at least one other fuel.

       Power Boiler - A combustion unit used to produce steam for
       process or electrical energy which is designed  to  burn oil,
       coal, or gas.

       Recovery Boiler - A combustion unit  used to produce steam
       for pulping and recovery operations, and to recover the
       spent chemicals from the cooking liquor.
3.1.3  ROLE OF CHEMICALS IN PULPING

       In wood pulping,  cooking chemicals  have the  function of
       dissolving the lignin that bonds  the cellulose  fibers
       together.   Ideally,  the chemical  process should dissolve
       all of the intercellular cementing  constituents and ex-
       traneous materials without affecting the cellulose fibers.
       Unfortunately, the ideal is never achieved.   Thus, various
       chemical processes have been developed' using acid, alka-
       line, or neutral  solutions, which delignify  with as little
       destruction of the cellulose as possible. All  of the pulp-
       ing processes  of  interest in this study utilize sulfur in
       some form  in the  cooking liquor.  In bringing about the
       solution of wood  components, the  sulfur reacts  with some
       of the wood components to produce compounds  which may de-
       grade the  quality of air or water if released into the
       environment.
                                  3-5

-------
 During the early development stages of the wood pulp industry,
 the use of chemicals was insignificant.  But as new chemical
 pulping techniques came into being and the need for pulp pro-
 ducts increased, it created an increasing demand for chemicals.
 Now the chemical requirements are such that it is an important
 segment of the chemical industry.

 Of the three major chemical pulping processes in use today,
 the sulfite process was the first.  Established in 1867, it
 used a calcium base cooking acid.  The raw materials, sulfur
 and limestone, were inexpensive and plentiful.  Pyrite,  in
 some areas where available, was used instead of sulfur for the
 formation of sulfur dioxide.  In place of limestone, some mills
 preferred the milk of lime system, which can be calcium hydroxide
 or a slurry of calcium carbonate.

 The use of magnesium as a base for sulfite pulping has been  known
 since 1874.  But because of the relatively high cost of the  chemi-
 cal make-up,  magnesium oxide, it was not commercialized until
 1948.   It was at this time that a recovery system was developed
 permitting the reuse of magnesium oxide and sulfur dioxide that  is
 recovered in the combustion of the spent liquor.

 In 1948 a number of calcium-base mills were converted to the use
 of ammonia.  The higher cost of the ammonia-base over the calcium-
 base  is  offset by a substantial increase in production because of
 a  25  percent decrease  in the time of a pulping cycle.

 Kraft pulping came  into being in 1879.  It was a
 modification  of the caustic soda system, whereby
 sodium sulfide was  added to the caustic soda cooking
 liquor.   The  introduction of the modern recovery fur-
 nace  in  the period  1928-1934 brought about a tremen-
 dous  increase in the use of kraft pulp.  Recovery of
 cooking  chemicals from kraft spent liquor is essential
 for the  kraft process  to be cost competitive with
 other processes.  The  recovery of chemicals is accom-
 plished by  spraying concentrated spent liquor into the
 recovery  furnace, where the organic compounds are
 burned and  an inorganic smelt of sodium sulfide and
 sodium carbonate is formed.   To make  up for chemicals
 lost  in the operating  cycle,  salt cake (sodium sulfate)
 is  usually  added to the concentrated  spent liquor before it  is
 sprayed into  the  furnace.

The smelt of  sodium sulfide  and sodium carbonate
 flows  from the  furnace  and  is  dissolved in water
to  form green liquor.   This  solution  is  reacted
with slaked lime  (calcium hydroxide),  converting the  green
liquor to cooking liquor which  is  a solution of
sodium hydroxide and sodium  sulfide.   The  calcium

                           3-6

-------
         carbonate created by  this reaction is settled out,
         dewatered,  and burned in a  lime kiln.  The resultant
         calcium oxide  is  returned for reaction with the
         green liquor.

         NSSC pulp is produced with  a neutral sulfite cooking
         liquor.  This  liquor  is prepared by reacting excess
         soda ash or caustic soda with sulfur dioxide pro-
         ducing a solution of  pH 8 to 11.  The chief use
         of NSSC pulp is in the production of corrugating
         medium for  board  grades.
  3.1.4  CHARACTERISITICS  OF EACH PROCESS

3.1.4.1  Kraft

         The Kraft process produces a dark colored fiber.  There-
         fore, the market  for the  unbleached pulp is usually limited
         to its use in board,  wrapping,  and bag papers.  If kraft
         pulp  is to be used  in the manufacture of fine white papers,
         its fibers must be  treated additionally in a bleach
         plant.

         Cooking chemicals  (caustic soda and sodium sulfide) are
         expensive to manufacture.  Thus their recovery is an economic
         necessity.  During  the recovery process, steam is produced
         from  the combustion of the organic materials, adding to
         the economic benefits of  the recovery system.

         The presence of caustic soda in the cooking liquor permits
         the pulping of practically all wood species.  The other active
         chemical, sodium sulfide, creates a chemical reaction during
         cooking that imparts  the  strength characteristics to kraft
         fibers, producing fibers  that are stronger than those made
         from NSSC or sulfite  processes.  Small amounts of sodium sulfide
         react with lignin and carbohydrates in the wood to form odorous
         compounds which may cause a reduction of air quality.
3.1.4.2  Neutral Sulfite Semichemical

        This process is mainly used for the production of a high yield
        pulp having a high crush strength, important for making corrugated
        board.  In addition, it utilizes hardwood species that are not
        readily adaptable to the other processes.  Coniferous woods are
        considered less desirable for the NSSC process because of a higher
        chemical consumption during cooking, high lignin content for a
        given yield, and high energy requirements for refining.
                                     3-7

-------
         NSSC pulp with high yields (75 to 80 percent)  is used mainly in
         the production of corrugating medium and linerboard.  Some is
         used for blending with kraft pulp for carton board, wrapping papers,
         et cetera.  If cooked to a yie;d in the range of 55 to 62 percent,
         NSSC pulps can be bleached and then blended with bleached sulfite
         for high grade papers.

         Recovery of chemicals from the spent liquor is not practiced
         at the majority of mills and, therefore, may create a water
         pollution problem.  Incineration of the liquor may, in turn,
         create an emission problem because of sulfur dioxide emission
         from the incinerator and will depend on the degree of sulfur
         di oxide re cove ry.
3.1.4.3  Sulfite
         The sulfite pulping process dominated the commercial pulping
         field from about 1890 to 1930,  producing easy bleaching pulps
         from non-resinous woods.  The cooking chemical was  calcium
         bisulfite plus free sulfurous acid.   The characteristics
         of the pulp make it suitable for use in many grades of paper
         but it is especially suitable for tissues and fine  papers.

         Recovery of cooking chemicals and the heat values in the
         spent cooking liquors was not widespread until fairly recent
         years when the older calcium base has been replaced in many
         mills by a soluble base such as sodium, magnesium,  or ammonium.
         Sodium and magnesium bases require recovery for economic reasons,
         Of the two, magnesium is more widespread in its use because
         on combustion the inorganic constituents break down directly
         to magnesium oxide and sulfur dioxide which can readily be
         recycled.   Spent liquors from ammonia base pulping  may be
         incinerated with recovery of most of the SO .   The  ammonia burns
         completely to nitrogen and water vapor.

         The trend  toward soluble bases  has improved the versatility
         of the sulfite process  in terms of wood species which can
         be pulped;  modifications  of the process  have  led to higher
         yields  of pulp from wood,  and recovery processes have not
         only  reduced water pollution, but stimulated  the development
         of chemical by-product  opportunities  unique to this process.
                                      3-8

-------
  3.1.5   FLOW DIAGRAMS AND  BASIS FOR SELECTION

         To describe major  pulping  operations, 17 basic flow diagrams,
         each with  a power  plant energy balance, have been prepared.
         These flow diagrams  illustrate the majority of pulping
         process variations now in  use in this country.  These
         are as follows:
3.1.5.1  Kraft  (10 Flow Diagrams)

        Table  3-1 lists the significant factors which influence the
        emission of  air pollutants  from the kraft pulping process and
        the particular factors that are to be included in each of the
        ten flow diagrams.

        Gas flow quantities from the turpentine condenser and the
        multiple effect evaporators have been assumed at 35 cubic feet
        per air dry  ton of pulp on  all kraft flow diagrams.  These may
        vary between 20 cubic feet  to 60 cubic feet and will depend on
        individual operations of the relief lines.

        For purposes of gas volume  calculations, the slaker vent has
        been assumed to be 40 feet  high with a diameter of 24 inches
        for a pulp production of 600 tons per day, giving a flow of
        7,000  cubic  feet per air dry ton of pulp.  This may vary to a
        low of 4,000 cubic feet per air dry ton.  Particulate emissions
        are unknown,  and since most of the particulates drop!within the
        mill area, this source can  be considered as a mill nuisance.
3.1.5.2  Neutral Sulfite Semichemical  (3 Flow Diagrams)

        1.  Combination of neutral sulfite semichemical and kraft
            pulping  (continuous digester).

        2.  Neutral sulfite semichemical without spent liquor recovery
            (batch digesters).

        3.  Fluidized bed recovery process  (continuous digester).
                                3-9

-------
   TABLE   3-1



KRAFT FLOW DIAGRAM FACTORS
PULPING
OPERATION
FLOW DIAGRAM NO.
123456789 10

Batch
Digester
Continuous
Digester
Concentrated Black
Liquor Oxidation
Weak Black Liquor
Oxidation
No
Oxidation
Direct Contact
Evap . Recovery
Venturi
Recovery
Bleach Plant
No Bleaching
Lime Kiln
Moderate Collec-
tion Efficiency
Lime Kiln High
Collection Efficiency
Fluidized Bed Calcining
High Collection
Efficiency
High Solids Evapora-
tor (63% Solids)
Long Tube Vertical
Evaporators
Hardwood (H) or
Softwood (S)
Percent Yield
Product
X X X X
X X X XXX
X
X X
X X X X X X X
XXXXXX XX
X
X X X X X
X X X X X
X XXX
XX XXX
X
X
xxxxxxxxx
SSSSSSSHS S
53 45 47 47 47 45 45 46 45 47
t^tflcnw ftf o 1-3 HOW owowow >v
H-p) >{ I ' fl> h{ O O *1 t ' HI ' H f-1 H I-* O
(D (D PJ (1) (D*XJ Qj&J 0j p QJ ) 0j QJ (&
H CD O ^fP>f ffDO (DOfl>Ofl>O H
                                     ft)
                                           (t>
           3-10

-------
3.1.5.3   Sulfite  (4 Flow Diagrams)

         1.  Magnesium acid sulfite, with recovery (batch digesters).

         2.  Calcium acid sulfite, without recovery (batch digesters).

         3.  Magnesium bisulfite  (magnefite) with recovery (batch digesters)

         4.  Ammonium acid sulfite, with liquor incineration (batch
            digesters).

         The flow diagrams have been prepared from an air quality point
         of view, and are broken down only to the extent necessary to
         clearly locate and identify emissions.


  3.1.6   POWER PLANT ENERGY BALANCE

         Power plant energy balances were developed in order to
         determine the emissions resulting from the generation of
         the steam required for process and electric power generation.
         In order to have a common base for comparison, the balances
         are based on supplying all of the specific steam and
         electrical requirements for each process with no outside
         purchase of either electricity or steam.  Steam and
         electrical usage and steam pressures have been assumed
         which are representative of actual mills utilizing the
         various processes.                                  j
                                                            1
         Since pulp mills must either produce dry pulp for shipment
         or are part of an integrated pulp and paper operation, the
         energy balances were developed to include the steam and
         electric loads associated with either a paper machine or pulp
         dryer.  In order to give an indication of'the steam and electric
         requirements of the pulp mill only, a second set of numbers
         has been included on each heat balance.  These pulp mill
         requirements were arrived at by performing a balance without
         the electric and steam requirements of a paper machine or
        pulp dryer.

        The amount of steam generated by the recovery boilers is
         calculated based on burning the black liquor solids at an
         efficiency of 60 percent.  The steam generated from bark
        burning is based on an efficiency of 70 percent.  The remaining
        steam is supplied by the power boiler(s) at an efficiency of
         85 percent for coal or fuel oil.  The quantity of coal or
         fuel oil required for the power boiler(s) is used as a basis
        to calculate the air emissions shown on the flow diagrams.
         In no case should the coal and oil emissions be added
         together.

                                      3-11

-------
  3.2  KRAFT
3.2.1  GENERAL DESCRIPTION OF KRAFT PROCESS

       The word kraft is derived from a Swedish word which means
       "strong," because kraft fibers are stronger than those
       produced by either the NSSC or the sulfite processes.

       The kraft process involves  the cooking of wood chips
       in either a batch or continuous digester, under pressure,
       in the presence of a cooking liquor.  The kraft cooking
       liquor contains sodium hydroxide and sodium sulfide,
       the hydroxide  being the reagent that dissolves the  lignin.
       During the cooking reaction the hydroxide is  consumed and
       the sodium sulfide serves  to buffer and sustain the cooking
       reaction.   At  the same time,  small amounts of sulfide react
       with lignin in the wood giving rise to the odors characteristic
       of kraft mills.

       Upon the completion of the  cook,  the residual pressure
       within the digester is  used to discharge the  pulp into
       a  blow tank.   Gases and flash steam released  in the tank
       are vented through a condenser, where heat is  recovered
       and the condensible vapors  removed.   The noncondensible
       gases,  which are  a source of  malodors,  are either con-
       fined and  treated or released to  the atmosphere.  At
       the same time  the pulp  in the blow tank is  being diluted
       and pumped to washers where the spent chemicals  and the
       organics from  the wood  are  separated from the  fibers.

       The  spent  chemicals  and the organics,  called black
       liquor,  are then  concentrated in multiple-effect
       evaporators and/or direct-contact  evaporators  for
       subsequent burning.  A  solids  content of 60-70 per-
       cent in  the black  liquor is a requirement for  com-
      bustion  in  the recovery  furnace.

      During evaporation of the black liquor  in  the multiple-
      effect evaporators volatile malodorous  gases
      are released.  These gases escape where  entrained gases
      and vapors are drawn off by a vacuum  system.  In order
      to eliminate the venting of these gases  to the atmosphere,
      they can be confined and destroyed.
                                 3-12

-------
       The black liquor may be concentrated further in a direct-
       contact evaporator using hot flue gases from the recovery
       furnace.  These hot:gases, containing carbon dioxide,
       react with sulfur compounds in the black liquor leading
       to the release of hydrogen sulfide.  Prior oxidation of
       the black liquor wi 3.1 reduce the sulfide content of the
       liquor and, hence, the amount of hydrogen sulfide released.

       The concentrated black liquor is then sprayed into the
       recovery furnace; where the organic content supports
       combustion.  The inorganic compounds, consisting of the
       cooking chemicals, fall to the bottom of the furnace
       where chemical reactions occur in a reducing atmosphere.
       The chemicals are withdrawn from the furnace as a molten
       smelt, which is dissolved in a smelt dissolving tank
       to form a solution called "green liquor."  The green
       liquor is then pumped from the smelt dissolving tank,
       treated with slaked lime, and then clarified.  The
       resulting liquor, referred to as "white liquor," is
       the cooking liquor used in the digesters.

       There are chemical losses from the kraft process, through
       air emissions, mill water effluent, and with the finished
       product.  These losses must be made up with purchased
       chemicals, usually salt cake (sodium sulfate).  The[ name
       "sulfate" process is derived from this make-up chemical.
3.2.2  BASIC DESCRIPTION OF KRAFT FLOW DIAGRAMS

       The basic assumptions which were made in the develop-
       ment of each kraft flow diagram, the diagram itself,
       and the energy balance are presented on the following
       pages.
                              3-13

-------
                           KRAFT DIAGRAM NO. 1
 TYPICAL LOCATION

     Southern United States.

 TYPICAL AGE OF EQUIPMENT

     Over 15 years

 GENERAL

     This flow diagram is based on production of base  stock  and
     should be used with Flow Diagram No.  5/  top liner stock,
     to illustrate air emissions from a linerboard pulp mill.
     Flow Diagram No. 1 depicts a relatively  old mill,  using
     batch digesters.  A comparison of emissions from  the  lime
     kiln is shown when using clean water  make-up  in the causti-
     cizing plant versus the  use of multiple-effect evaporator
     combined condensate.

     There are perhaps 30 to  40 mills in the  United States that
     are illustrated by Flow  Diagram No. 1.   These must be combined
     with those mills represented by Flow  Diagram  No.  5.

 EMISSIONS
    The  following emissions have been selected as representative,
    based  on the range of emissions presented in Chapter 4.

                    POUNDS PER AIR DRY TON OF UNBLEACHED PULP
      Location

Blow Tank Accumulator

Washers and Screens

M. E. Evaporators

R. Boiler and D. c.
     Evaporators

After Precipitator

Smelt Dissolving Tank

Slaker

~*2i
r 0.10
0.01
0.50
10.7
10.7
k 0.02
0
RSH,
RSR,
RSSR
2.90
0.12
0.4
1.4
1.4
0.05
0
so
.
0
0
0
3.4
3.4
0
0
Par-
ticulate
0
0
0
81.8
9.8
4.0
Unknown
                                   3-14

-------
                           KRAFT  DIAGRAM NO.  1
                              (Continued)


EMISSIONS  - Continued


H2S
1.2
0.48
0.01
RSH,
RSR,
RSSR
1.25
0.50
0.51


so2
0.1
Trace
0

Par-
ticulate
23.5
4.3
0
                    POUNDS  PER AIR DRY TON OF UNBLEACHED PULP
      Location


Lime Kiln

Lime Kiln Scrubber

Turpentine Condenser


ASSUMPTIONS

      The following  assumptions have been made in developing the
      flow diagram:

A.   PULP  MILL

    1.  Pulp Yield = 53 Percent.

    2.  Cooking  liquor charge per air dry ton of brown stock
       equals 5,050 pounds of which 780 pounds are chemical
       solids.  Sulfidity equals 27 percent.

    3.  Black  liquor solids from first stage washer equals
       15  percent and from M. E. Evaporators equals 50 percent
       solids.

B.   RECOVERY

    1.  Unit operating at 15 percent excess air at economizer
       outlet.

    2.  Particulate  matter of 8 grains per SDCF leaving the
       economizer.

    3.  Efficiency of 50 percent on particulate removal in
       the direct contact evaporators.

    4.  Steam shatter jets utilized on smelt spouts.

    5.  Design efficiency of 95 percent for precipitator with
       an  annual  average operating efficiency of 88 percent.

                              3-15

-------
                              KRAFT DIAGRAM NO. 1
                                  (Continued)

ASSUMPTIONS - Continued
C.  CAUSTICIZING

    1.  Lime kiln SO  emission has been assumed at 0.1 pound
        per air dry ton of pulp.

    2.  Lime kiln scrubber efficiency assumed to be 80 per-
        cent on lime and 60 percent efficiency on soda.

D.  POWER PLANT

    1.  Excess air:  30 percent for bark/  10  percent for
        oil and 20 percent for coal.

    2.  Bark burning equipment is  a low set spreader stoker.

    3.  Reinjection from dust  collector:   50  percent for
        bark and 0 percent for coal.

    4.  Design efficiencies  for dust collector:  80  percent
        on bark and 90  percent on  coal with annual  operating
        efficiencies  of 78 percent and  88 percent,  respectively.

    5.   Bark  is burned  24 hours per day at a  controlled rate.

    6.   Unburned combustible in refuse leaving the dust
        collector  is  40 percent.

    7.   Coal  firing based on pulverized coal or spreader stoker.
                               3-16

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
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[60]
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-------
                                 KRAFT DIAGRAM NO. 2
 TYPICAL LOCATION

     Western United States.

 TYPICAL AGE OF EQUIPMENT

     Under five years.

 GENERAL

     Flow Diagram No. 2 contains a fluidized bed calcining system.
     This flow diagram is based on production of bleached soft-
     wood kraft pulp and depicts a new mill designed with emphasis
     on odor abatement and reduced particulate emission.   It
     includes treatment of the noncondesible gases from digester
     and multiple-effect evaporators with bleach plant chlorination
     effluent.  Flow Diagram No. 2 represents a new mill  designed
     for a production of 150 to 500 tons per day.  There  are perhaps
     two or three mills in the U.  S. that are illustrated by this
     flow diagram.

 EMISSIONS
     The following emissions  have been selected as  representative,
     based on the range of emissions  presented in Chapter 4.
                       POUNDS  PER AIR DRY  TON  OF  UNBLEACHED PULP
 Location


 Washers and Screens

 BLO Tower

 M. E. Evaporators

 R. Boiler and D. C.
      Evaporators

After Precipitator

After Scrubber

Smelt Dissolving Tank
0
0
0
1
1
1
0
2s
.08
.02
.02
.50
.50
.51
.02
RSH,
RSR,
RSSR
0.45
0.30
0.18
Trace
Trace
0.3*
0.02
so2
0
0
0
5.4
5.4
5.4
0
Par-
ticulate
0
0
0
116
3.48
1.0
1.0
                                 3-18

-------
                                KRAFT  DIAGRAM NO.  2
                                   (Continued)
EMISSIONS  -  Continued
                                           RSH,
                                           RSR,             Par-
                                H  S        RSSR      SO,,     ticulate
Location                          2        	       2     	

slaker                           000       unknown

Fluidized Bed Calciner           unknown    unknown   unknown   72.0

Fluidized Bed Calciner
Scrubber                         unknown    unknown   unknown    0.7

Turpentine Condenser             0.01       0.43      0         0

*Note:  This is a result of  introducing the weak liquor oxidation
       system off-gases into  the inlet of  the  scrubber.


ASSUMPTIONS
    The  following assumptions have been made  in  developing the
    flow diagram:

    A.   PULP MILL

         1.  Pulp Yield =  45 Percent,

         2.  Cooking liquor charge per  air dry ton  of brown stock
            equals 6,996  pounds of which 996 pounds are  chemical
            solids.  Sulfidity equals  25 percent.

         3.  It is assumed that there is no production of  turpentine
            and soap.

         4.  Weak liquor oxidation system ahead of  the multiple-
            effect evaporators.  Oxidation efficiency assumed
            at 99 plus percent.

    B.   BLEACH PLANT

         1.  It was assumed as a six stage bleach plant with a
            chlorine emission to atmosphere of one pound  per
            air dry ton of pulp.
                                  3-19

-------
 C.   RECOVERY

     1.   Unit operating at 15 percent excess air at econo-
         mizer outlet.

     2.   Particulate matter of 8 grains per SDCP leaving
         the economizer.

     3.   Efficiency of 50 percent on particulate removal in
         the direct contact evaporators.

     4.   Steam shatter jets utilized on smelt spouts.

     5.   Design efficiency of 98 percent for precipitator with
         an annual average operating efficiency of 97 percent.

     6.   Efficiency of 70 percent on particulate removal in the
         scrubber.

D.   CAU5TICIZING

     1.   Particulate emissions from cyclones assumed at 6 tons
        per day for 165 ADT/Day unbleached pulp.

     2.   Scrubber efficiency assumed at 99 percent on lime.
E.  POWER PLANT

    1.  Excess air:  30 percent for bark, 10 percent for oil
        and 20 percent for coal.

    2.  Bark burning equipment is a low set spreader stoker.

    3.  Reinjection from dust collector:  50 percent for bark
        and 0 percent for coal.

    4.  Design efficiencies for  dust collector:   82 percent
        on bark and 92 percent on coal with annual operating
        efficiencies of 80 percen  and 90 percent, respectively,

    5.  Bark is burned 24 hours  per day at a controlled rate.

    6.  Unburned combustible in  refuse leaving the dust col-
        ector is 40 percent.

    7.  Coal firing based on pulverized coal.
                             3-20

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
        r-i 00
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                                           [480]
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        [480]
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[550]
850 KW-HR

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                                                                                      03
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                                                                                      '(M
                                                                               POWER PLANT AUX.
                                                                                   [3OOO]
                                                                                   3000 LBS.
                                                                                    [MOO]
                                                                                   1100 LBS.
                                                                                                        [I860]
                                                                                                       I860 LBS.
                                                                   [600]
                                                                   600 LBS.
                                                                                     [0]
                                                                                   5000 LBS.
                                                                                   [2640]
                                                                                   2640 LBS.
                                                                                             BLEACH PLANT
                                                                                            -**-
                                                                              DIGESTERS
                                                                                                                    WASHING
                                                                                                                   PULP DRYER
                                                                                             EVAPORATORS
                                                                                    [240]
                                                                                   240 LBS.
                                                                                             CAUSTICIZING
                                                                                   So
 NOTES:

-**- AMPLE HOT WATER
 ASSUMED  TO BE AVAILABLE.

[ ] INDICATES FLOWS FOR
 PULP MILL ONLY.
ALL FLOW RATES AND
 KILOWATTS ARE PER TON
OF A.D. PULP.
                                             TO DESUPERHEATERS
                                                 1160 LBS.
                                                 [800]
                CONTINUOUS DlGESTERSjWEAK BLACK LIQUOR OXIDATION,
                DIRECT CONTACT EVAPORATORS, BLEACHING, HIGH EFFICIENCY
                LIME KILN COLLECTION.
                                                                           POWER PLANT ENERGY BALANCE
                                                                               KRAFT PROCESS  NO.  2 *
                                                                                                                             EXHIBIT NO,
                                                                     SYSTEMS ANALYSIS STUDY OF
                                                         EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
                                                                       CONTRACT NO. CPA 22-69-18
                                                                                  FOR
                                                          DEPARTMENT OF HEALTH, EDUCATION AND WELFARE
                                                         CONSUMER PROTECTION AND  ENVIRONMENTAL HEALTH SERVICE
                                                              NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                     ENVIRONMENTAL ENGINEERING, INC.
                                                            GAINESVILLE, FLORIDA
                                                                       J. E. SIRRINE COMPANY, ENGINEERS
                                                                                                                    GREENVILLE, S. C.

-------
                           KRAFT DIAGRAM NO.  3


TYPICAL  LOCATION

     Western  United  States.

TYPICAL  AGE OF EQUIPMENT

     Ten to 15 years with  upgraded  emissions  control equipment.

GENERAL

     This  flow diagram, based on production of unbleached softwood
     kraft pulp, depicts a mill designed with emphasis on odor abate-
     ment.  It includes incineration in the lime kiln of the non-
     condensible gases, from the batch digesters and multiple-effect
     evaporators.  There are perhaps 4 to 6 mills in the U. S. which
     are illustrated by this flow diagram.

EMISSIONS
     The following emissions have been selected as representative,
     based on the range of emissions presented in Chapter 4.
              POUNDS PER AIR DRY TON OF UNBLEACHED PULP
Location


Accumulator

Washers and

BLO Tower

M  E-  Evaporators

R. Boiler and D. C.
      Evaporator

After Precipitator
RSH,
RSR,
H S RSSR
0.10 3.35
:reens 0.02 0.20
0.02 0.25
:ors 0.01 0.4
D. C.
.or 5,0 Trace
.ator 5.0 Trace
so2
0
0
0
0
4.6
4.6
Par-
ti culate
0
0
0
0
106
8.50
                                 3-22

-------
                           KRAFT DIAGRAM NO. 3
EMISSIONS  - Continued
Location
After Scrubber

Smelt Dissolving
       Tank

Slaker

Lime Kiln

Lime Kiln Scrubber

Turpentine Con-
denser
(Continued)
H2S
5.0
0.02
0
1.00
0.2
RSH,
RSR,
RSSR
Trace
0.02
0
0.6
0.30
so2
4.6
0
0
Trace
Trace
                              Par-
                              ti culate
                              1.7


                              1.0

                              Unknown

                              51

                              0.5
0.01
0.40
ASSUMPTIONS
     The following assumptions have been made in developing the
     flow diagram:

     A.   PULP MILL
         1.   Pulp Yield = 47 Percent

         2.   Cooking liquor charge per air dry ton of brown stock
             equals 6,335 pounds of which 900 pounds are chemical
             solids.  Sulfidity equals 25 percent.

         3.   It was assumed that there is no soap skimming system
             since only small quantities of soap are produced.

         4.   Weak liquor oxidation system ahead of the black liquor
             evaporators.  Oxidation efficiency was assumed at  90
             percent.
                              3-23

-------
                      KRAFT DIAGRAM NO. 3
                           (Continued)

B.  RECOVERY

    1.  Unit operating at  15 percent excess air at econo-
        mizer outlet.

    2.  Particulate matter of 8 grains per SDCF leaving the
        economizer,

    3.  Efficiency of 50 percent on particulate removal in
        the direct contact evaporators.

    4.  Steam shatter jets utilized on smelt spouts.

    5.  Design efficiency of 95 percent for precipitator with
        an annual average operating efficiency of 92 percent.

    6.  Efficiency of 80 percent on particulate removal in
        the scrubber.

C.  CAUSTICIZING

    1.  Lime kiln scrubber efficiency assumed at 99 percent
        on lime and 80 percent efficiency on soda.

D.  POWER PLANT

    1.  Excess air:  30 percent for bark, 10 percent for
        oil and 20 percent for coal.

    2.  Bark burning equipment is a low set spreader stoker.

    3.  Reinjection from dust collector:  50 percent for
        bark and 0 percent for coal.

    4.  Design efficiencies for dust collector:  82 percent
        on bark and 96 percent on coal with annual operating
        efficiencies of 80 percent and 95 percent, respec-
        tively.

    5.  Bark is burned 24 hours per day at a controlled rate.

    6.  Unburned combustible in refuse leaving the dust collector
        is 40 percent.

    7.  Coal firing based on pulverized coal.
                              3-24

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
O4
I
r\)
01
                                [12,030]
                               21,000 U3b,
                                                                     650F
                            COAL/OIL!   BARK
                             COMBINATION BOILER
  REC.
BOILER
                                     DEAERATING
                                      HEATER
                                                     POWER PLANT AUX
                                                                                                                DIGESTERS
                                                                                             WASHING
                                                                                                               PAPER MACHINES
                                                                                                             * EVAPORATORS
                                                                                                                CAUSTIC I ZING
                                                                                           NOTES:
                                                                                           [ ] INDICATES FLOWS FOR
                                                                                           PULP MILL ONLY.

                                                                                           ALL FLOW RATES  AND
                                                                                           KILOWATTS ARE PER
                                                                                           TOM OF A.D. PULP.
                       i-.fif'.^, nASr. STOCK, At A^ LiCUOR OXIDATION, NO BLEACHING
                      ONTACT EVAPORATORS, -ion LL'.'K KILN COLLECTION EFFICIENCY.
                                                                      POWER PLANT ENERGY  BALANCE
                                                                         KRAFT PROCESS  NO.  3 *
                                                                                                                       EXHIBIT NO.
                                                                 SYSTEMS ANALYSIS STUDY OF
                                                      EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
                                                                   CONTRACT NO. CPA 22-69-18
                                                                             FOR
                                                       DEPARTMENT OF HEALTH.  EDUCATION AND WELFARE
                                                      CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
                                                           NATIONAL AIR POLLUTION  CONTROL ADMINISTRATION
                                                                       ENVIRONMENTAL ENGINEERING, INC.
                                                                             GAINESVILLE. FLORIDA
                                                                                   J. E. SIRRINE COMPANY, ENGINEERS
                                                                                                               GREENVILLE. S. C.

-------
                          KRAFT DIAGRAM NO. 4
TYPICAL LOCATION

     Southern United States.

TYPICAL AGE OF EQUIPMENT

     Under five years.

GENERAL

     This flow diagram is based on production of kraft softwood paper
     stock.  It depicts a new mill designed to provide some odor
     abatement, consisting of a concentrated liquor oxidation system,
     a scrubber in the noncondensible gases from the black" liquor 
     evaporators and a mesh pad in the dissolving tank vent.  A
     comparison of emissions from the lime kiln is shown when using
     clean water make-up in the causticizing plant versus the use
     of evaporator combined condensate.  There are perhaps 10 to 20
     mills in the U. S. that are illustrated by this flow diagram.

EMISSIONS
     The following emissions have been selected as representative,
     based on the range of emissions presented in Chapter 4.

                 POUNDS PER AIR DRY TON OF UNBLEACHED PULP
LOCATION


Washers and Screens

M. E. Evaporators

BLO Tower

R. Boiler and D. C.
     Evaporators

After Precipitators

Smelt Dissolving Tank

Slaker
RSH,
RSR,
H S RSSR SO
;ns 0.02 0.24 0
; 0.40 0.41 0
0.02 0.31 0
C.
1.5 0.12 4.4
>rs 1.5 0.12 4.4
Tank 0.02 0.02 0
00 0
Par-
ti culate
0
0
0
106
3.18
1.0
Unknown
                               3-26

-------
                           KRAFT DIAGRAM NO.  4
                              (Continued)


EMISSIONS - Continued


                 POUNDS PER AIR DRY TON OF UNBLEACHED PULP
LOCATION
Lime KiIn

Lime Kiln Scrubber

Turpentine Condenser


ASSUMPTIONS


H2S
1.0
r 0.2
ser 0.01
RSH,
RSR,
RSSR
0.5
0.10
0.50

Par-
SO ticulate
Trace 25
Trace 0.2
0 0
    The following assumptions have been made in developing the
    flow diagram:

    A.  PULP MILL


        1.  Pulp Yield = 47 Percent.

        2.  Cooking liquor charge per air dry ton of brown stock
            equals 6,189 pounds of which 889 pounds are chemical
            solids.  Sulfidity equals 26 percent.

        3.  Assumed concentrated black liquor oxidation at approximately
            99 percent efficiency.

    B.  RECOVERY
        1.   Unit operating at 15 percent excess  air at econo-
            mizer outlet.

        2.   Particulate matter of 8 grains  per SDCF leaving  the
            economizer.

        3.   Efficiency of  50  percent on particulate removal  in
            the  direct contact evaporators.

        4.   Steam shatter  jets utilized on  smelt spouts.

        5.   Design efficiency of 99 percent for  precipitator with
            an annual  average operating efficiency  of  97 percent.

                             3-27

-------
C.  CAUSTICIZING

    1.  Lime kiln scrubber efficiency assumed at  99  percent
        on lime and 80 percent efficiency  on soda.

D.  POWER PLANT

    1.  Excess air:  30 percent for bark,  10 percent for
        oil and 20 percent for coal.

    2.  Bark burning equipment is  a low  set spreader stoker.

    3.  Reinjection from dust collector:   50 percent for
        bark and 0 percent for coal.

    4.  Design efficiencies  for dust collector:   92  percent
        on bark and 95 percent on  coal with annual operating
        efficiencies of 90 percent and 93  percent, respectively.

    5.  Bark is burned 24 hours per day  at a controlled
        rate.

    6.  Unburned combustible in refuse leaving the dust
        collector is 40 percent.

    7.  Coal firing based on pulverized  coal.
                      3-28

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
         o -'
         2
            OC
           h-LU
           0$:
           00
           CO-J
            CD
CM
I
no
CD
                                 [9280]
                                18,820 LBS
                                                             650 PSIG   900 F



[550]
850 KW-HR

                                                                                        23
                              COMBINATION BOILER
                      'I l/>
                      O CD
                      1 -1
                      1 O
                      T *
                      ' 
-------
                           KRAFT DIAGRAM NO. 5
TYPICAL LOCATION

    Southern United States.

TYPICAL AGE OF EQUIPMENT

    Over 15 years.

GENERAL

    This flow diagram is based on production of top liner stock
    and should be used with Flow Diagram No. 1, base stock, to
    determine air emissions from a linerboard mill.  Flow Diagram
    No. 5 depicts a relatively old mill, using batch digesters,
    and with no provisions for odor abatement.  There are perhaps
    30 to 40 mills in the U. S. which are illustrated by this flow
    diagram.

EMISSIONS

    The following emissions have been selected as representative,
    based on the range of emissions presented in Chapter 4.
                                3-30

-------
EMISSIONS  -
               KRAFT DIAGRAM NO. 5
                    (Continued)

Continued

   POUNDS PER AIR DRY TON OF UNBLEACHED PULP
LOCATION


Accumulator

Washers and Screens

M. E.  Evaporators

R. Boilers  and D.  C.
      Evaporators       14.6

After  Precipitators    14.6

Smelt  Dissolving Tank   0.04

Slaker                   0

Line Kiln                1.0

Line Kiln Scrubber      0.40

Turpentine  Condenser     0.01


H S
2
0.12
eens 0.02
rs 0.50
RSH,
RSR,
RSSR

3.35
0.17
0.31


so.,
	 2
0
0
0

P ar-
ticulate

0
0
0
                      1.50       4.8     91.8

                      1.50       4.8     11.0

                      0.05        0       4.0

                       0          0      Unknown

                      0.6         0.1    51

                      0.23        Trace  10.0

                      0.50        0        0
ASSUMPTIONS
    The following  assumptions  have been made in developing the
    flow diagram:

    A.  PULP MILL

        1.  Pulp Yield  =  47  Percent.

        2.  Cooking  liquor charge per air dry ton of brown stock
            equals 6,335  pounds  of which 900 pounds are chemical
            solids.   Sulfidity equals 25 percent.

        3.  Black  liquor  solids  from  first stage washer equals 15
            percent  and from evaporators equals 50 percent solids,
                                3-31

-------
                          KRAFT DIAGRAM NO.  5
                              (Continued)

ASSUMPTIONS - Continued

    B.  RECOVERY

        1.  Unit operating at 15 percent excess  air at econo-
            mizer outlet.

        2.  Particulate matter of 8 grains per SDCF leaving
            the economizer.

        3.  Efficiency of 50 percent on particulate removal in
            the direct contact evaporators.

        4.  Steam shatter jets utilized on smelt spouts.

        5.  Design efficiency of 95 percent  for  precipitator
            with an annual average operating efficiency of 88
            percent.

    C.  CAUSTICIZING

        1.  Lime kiln SO  emission has  been  assumed at 0.1
            pounds per air dry ton of pulp.

        2.  Lime kiln scrubber efficiency assumed at 80 percent
            on lime and 60 percent efficiency on soda.

    D.  POWER PLANT

        1.  Excess air:  30 percent for bark, 10 percent  for
            oil and 20 percent for coal.

        2.  Bark burning equipment is a low  set  spreader  stoker.

        3.  Reinjection from dust collector:   50 percent  for
            bark and 0 percent for coal.

        4.  Design efficiencies  for dust collector:   80 percent
            on bark and 90 percent on coal with  annual operating
            efficiencies of 78 percent  and 88 percent,  respec-
            tively .

        5.   Bark is burned 24 hours per day  at a controlled rate.

        6.   Unburned combustible in the refuse leaving the dust
            collector is 40 percent.

        7.   Coal firing based on pulverized  coal.

                               3-32

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
OJ
OJ
OJ
                             [12,170]
                            21,110 LBS
                                                       650 PSIG   640 F
                           COAL/OIL!   BARK
                                 _t_ 	 	 	
                            COMBINATION BOILER
                                   DEAERATING
                                      HEATER
                                     DIGESTERS
                                                                                                               WASHING
                                                                                                            PAPER MACHINES
                                                                                                             EVAPORATORS
                                                                                                              CAUSTICIZING
                                                                                                              NOTES:
                                                                                                              [ ] INDICATES FLOWS FOR
                                                                                                              PULP MILL ONLY.
                                                                                                              ALL FLOW RATES AND
                                                                                                              KILOWATTS ARE PER TON
                                                                                                              OF A.D. PULP
                                              70 LBS.
                                               [70]

             TOP L \EROR PAPER STOCK, BA^CH I? IGESTE RS, \J0 OXIDATION, DIRECT
             CONTACT EVAPORATOR RECOVERY, \C BLEACHING, AND UME KILN
             MODERATE COLLECTION EFFICIENCY.
                                                                        POWER PLANT ENERGY BALANCE
                                                                        KRAFT PROCESS  N0.5*
                                                                                                                       EXHIBIT  NO.
           SYSTEMS ANALYSIS STUDY OF
EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
             CONTRACT NO. CPA 22-69-18
                       FOR
 DEPARTMENT OF HEALTH. EDUCATION AND WELFARE
CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
    NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                                      ENVIRONMENTAL ENGINEERING, INC.
                             J. E. SIRRINE COMPANY, ENGINEERS
                                                                            GAINESVILLE. FLORIDA
                                                                                                              GREENVILLE, S. C.

-------
                             KRAFT DIAGRAM NO. 6
TYPICAL LOCATION

     Southern United States.

TYPICAL AGE OF EQUIPMENT

     Five to ten years.

GENERAL

     This flow diagram is based on cooking in an early design
     continuous type .digester with no washing.  A bleach plant is
     included.  The flow diagram depicts a mill with minor provisions
     for odor abatement.  There are perhaps 10 to 20 mills in the
     U. S. that are illustrated by this flow diagram.

EMISSIONS
     The following emissions have been selected as representative,
     based on the range of emissions presented in Chapter 4.

               POUNDS PER AIR DRY TON OF UNBLEACHED PULP
LOCATION

Washers and Screens

M. E. Evaporators

R. Boiler and D. C.
     Evaporator
After Precipitators

Smelt Dissol-

Slaker

Lime Kiln

Lime Kiln Scrubber

Turpentine Condenser
RSH,
RSR,
H S RSSR
eens 0.02 0.23
rs 0.50 0.28
. C.
17.5 1.95
tors 17.5 1.95
g Tank 0.02 0.02
0 0
1.0 0.5
ber 0.40 0.20
enser 0.01 0.30
so2
0
0
5.0
5.0
0
0
Trace
Trace
0
Par-
ticulate
0
0
118
5.90
1.0
Unknown
31.5
6.3
0
                                3-34

-------
                           KRAFT DIAGRAM NO.  6
                              (Continued)
ASSUMPTIONS
     The following assumptions have been made in  developing  the
     flow diagram:

     A.   PULP MILL

         1.   Pulp Yield = 45   Percent.

         2.   Cooking liquor charge per  air dry ton of brown  stock
             equals 8,106 pounds  of which 1/150  pounds  are  chemi-
             cal solids.   Sulfidity equals 27 percent.

         3.   Black liquor solids  from first stage washer equals
             16  percent and from  evaporators equals  50 percent
             solids.

     B.   BLEACH  PLANT

         1.   Assumed  a  five stage Bleach  Plant with  a chlorine
             emission of  one pound per  air dry ton of pulp.

     C.   RECOVERY
         1.   Unit  operating  at  15 percent excess air at econo-
             mizer outlet.

         2.   Parciculate matter of 8 grains per SDCF leaving the
             economizer.

         3.   Efficiency of 50 percent on particulate removal in
             the direct contact evaporators.

         4.   Steam shatter jets utilized on smelt spouts.

         5,   Design efficiency  of 98 percent for precipitator
             with  an annual  average operating efficiency of 95
             percent.

    D.   CAUSTICIZING

         1.   Lime  kiln scrubber efficiency assumed at 80 percent
             or. lime and 60 percent efficiency on soda.
                            3-35

-------
E.  POWER PLANT

    1.  Excess air:  30 percent for bark,  10 percent for oil
        and 20 percent for coal.

    2.  Bark burning equipment is a low set spreader stoker.

    3.  Reinjection from dust collector:   50 percent for
        bark and 0 percent for coal.

    4.  Design efficiencies for dust collector:   92  percent
        on bark and 95 percent on coal with annual operating
        efficiencies of 90 percent and 93  percent, respec-
        tively.

    5.  Bark is burned 24 hours per day at a controlled rate.

    6.  Unburned combustible in refuse leaving the dust
        collector is 40 percent.

    7.  Coal firing based on pulverized coal.
                           3-36

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
O4
I
OJ
-si
                                [15,150]
                               24,860 LBS.
                                                        850 PSI6
                                                                   900 F
                              COAL/OIL!   BARK
                              COMBINATION BOILER
                                                                                                                 ** AMPLE HOT WATER
                                                                                                                 ASSUMED TO BE AVAILABLE.

                                                                                                                 [ ] INDICATES FLOWS FOR
                                                                                                                 PULP MILL ONLY.
                                                                                                                 ALL FLOW RATES AND
                                                                                                                 KILOWATTS ARE PER TON
                                                                                                                 OF A.D. PULP.'
                                                  i 500 LBS.
                                                   [720]

                                    : :CCr , NO C\ IDA- ;CN , DIRECT
                                          , VCDERATE LIME KILN
                 .ECTION EFFICIENCY
                                                                          POWER PLANT ENERGY BALANCE
                                                                             KRAFT PROCESS NO. 6 *
                                                                                                                          EXHIBIT NO.
           SYSTEMS ANALYSIS STUDY OF
EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
             CONTRACT NO. CPA 22-69-18
                        FOR
 DEPARTMENT OF HEALTH. EDUCATION AND WELFARE
CONSUMER PROTECTION AND  ENVIRONMENTAL HEALTH SERVICE
     NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                                         ENVIRONMENTAL ENGINEERING, INC.
                                                                               GAINESVILLE. FLORIDA
                              J. E. SIRRINE COMPANY, ENGINEERS
                                     GREENVILLE. S. C.

-------
                                KRAFT DIAGRAM NO. 7


TYPICAL LOCATION

     Northeastern United States.

TYPICAL AGE OF EQUIPMENT

     Ten to 15 years.

GENERAL

     This flow diagram is based on production of bleached stock with
     cooking done in batch digesters.  This flow diagram depicts the use
     of a Venturi scrubber rather than the commonly used electrostatic
     precipitator.  A mesh pad has been assumed in the vent from the
     smelt dissolving tank.  There are perhaps 15 to 25 mills in the
     U. S. that are illustrated by this flow diagram.

EMISSIONS
     The following emissions have been selected as representative,
     based on the range of emissions presented in Chapter 4.
                     POUNDS PER AIR DRY TON OF UNBLEACHED PULP
LOCATION


Accumulator

Washers and Screens

M. E. Evaporators

Recovery Boiler
After Venturi
Scrubber

Smelt Dissolving
Tank

Slaker

Lime Kiln

Lime Kiln After
Scrubber

Turpentine Condenser


H2S
0.12
0.01
0.50
RSH,
RSR,
RSSR
2.97
0.22
0.41

Par-
S0_ ticulate
0 0
0 0
0 0
8.0
0.4
1.4
0.02       0.02

 0          0

1.0        0.6
0.23
0.01       0.50

      3-38
2.3
Trace

 0
47.6
            0         1.00

            0        Unknown

           Trace     55
11.0

 0

-------
                           KRAFT DIAGRAM NO.  7
                              (Continued)
ASSUMPTIONS
     The following assumptions have been made in developing  the
     flow diagram:

     A.   PULP MILL

         1.   Pulp Yield = 45 Percent.

         2.   Cooking liquor charge per air dry ton of brown  stock
             equals 6,996 pounds of which 996 pounds are  chemi-
             cal soids.  Sulfidity equals 25  percent.

         3.   Black liquor solids from  first stage washer  equals
             15.5 percent and from M.  E.  Evaporators equals
             50 percent solids.

     B.   BLEACH PLANT

         1.   Assumed a five stage bleach  plant with a chlorine
             emission of one pound per air dry ton of pulp.

     C.   RECOVERY

         1.   Unit operating at 15 percent excess  air at econo-
             mizer outlet.

         2.   Particulate matter of 8 grains per SDCF leaving
             the economizer.

         3.   Steam shatter  jets utilized  on smelt spouts.

         4.   Design efficiency of 90 percent  for  Venturi  scrubber
             with an annual average operating efficiency  of  80
             percent.

         5.   Efficiency of  80 percent  on  particulate removal in
             the scrubber.

     D.   CAUSTICIZING

         1.   Lime Kiln scrubber efficiency assumed at 80 percent
             on lime  and 60 percent efficiency  on soda.
                              3-39

-------
                       KRAFT DIAGRAM NO.  7
                          (Continued)
E.  POWER PLANT

    1.  Excess air:  30 percent for bark,  10 percent for
        oil and 20 percent for coal.

    2.  Bark burning equipment is a low set spreader stoker.

    3.  Reinjection from dust collector:   50 percent for
        bark and 0 percent for coal.

    4.  Design efficiencies for dust collector:   80 percent
        on bark and 90 percent on coal with annual operating
        efficiencies of 78 percent and 88  percent, respec-
        tively.

    5.  Bark is burned 24 hours per day at a controlled
        rate.

    6.  Unburned combustible in refuse leaving the dust
        collector is 40 percent.

    7.  Coal firing based on pulverized coal.
                           3-40

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
          8
            ID
o-
O;
C0(
             CO
OJ
                              [19,230]
                              28,920 LBS.
                                                          650 PSIG
                                                                      640 F
                            COMBINATION BOILER
                      O UJ
                      o
                                  I860 LBS.

c/i
^ O
-i!o
!
[8160]
MAKE-UP 9060LBS.
in
r i_l
i 	 i in
z
o
> i
i/i
Q
I 	 J CO
' 1

DEAERATING
HEATER
O
0



[750]
I050KW-HR

                                                                          80 PSIG
                                                                    I60PSIG
                                                                                                 ID ID
                                                                                                 '-'In
                                                                                           40 LBS.
                                                                                            [20]
                                                                               POWER PLANTAUX.
                                                                                                        [2900]
                                                                                                        2900 IBS.
                                                                                             [3500]
                                                                                            3500 L6S.
                                                                                                        [3100]
                                                                                                        3100 UBS.
                                                                                                          [110]
                                                                                                         110  LBS.
                                                                                                                  BLEACH  PLANT
                                                                                                                    DIGESTERS
                                                                                              [500]
                                                                                             500 LBS.
                                                                                                          [0]
                                                                                                        9000 LBS.
                                                                                                                     WASHING
                                                                                                                 PAPER MACHINES
                                                                                                                   EVAPORATORS
                                                                                                                   CA'JSTICIZING
                                                                                                     NOTES:

                                                                                                     -** AMPLE HOT WATER ASSUMED
                                                                                                     TO BE AVAILABLE.

                                                                                                     L ] INDICATES FLOWS FOR
                                                                                                     PULP MILL ONLY.

                                                                                                     ALL FLOW RATES AND KILOWATTS
                                                                                                     ARE PER TON OF A.O. PULP.
                                       !
                                               TO DESUPERHEATERS
                                                       80 LBS.
                                                        [70]
           BATCH DlC-ESTERS, NO BLACK LIQUOR OXIDATION, VENTURl RECOVERY. SOFTWOOD
           BLEACHING, LIME KILN MODERATE COLLECTION EFFICIENCY.
                                                                            POWER PLANT ENERGY BALANCE
                                                                               KRAFT ^ROCESS  NO. 7 *
                                                                                                                             EXHIBIT  NO.
                                                                              SYSTEMS ANALYSIS STUDY OF
                                                                  EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
                                                                                CONTRACT NO. CPA 22-69-18
                                                                                           FOR
                                                                   DEPARTMENT OF HEALTH.  EDUCATION AND WELFARE
                                                                   CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH  SERVICE
                                                                       NATIONAL AIR POLLUTION  CONTROL ADMINISTRATION
                                                                          ENVIRONMENTAL ENGINEERING, INC.
                                                                                 GAINESVILLE. FLORIDA
                                                                                                 J. E. SIRRINE COMPANY, ENGINEERS
                                                                                                                    GREENVILLE. S. C.

-------
                           KRAFT DIAGRAM NO. 8
TYPICAL LOCATION

     Midwestern United States.

TYPICAL AGE OF EQUIPMENT

     Under five years.

GENERAL

     This flow diagram is based on production of bleached hard-
     wood pulp in a continuous digester.  It depicts a relatively
     new mill with a system for the treatment of noncondensible
     gases from the digester, multiple effect evaporators and
     the combined condensate from the multiple effect evaporators.
     There are perhaps 1 to 4 mills in the U. S. which are illustrated
     by this flow diagram.

EMISSIONS

     The following emissions have been selected as representative,
     based on the range of emissionspresented in Chapter 4.

                 POUNDS PER AIR DRY TON OF UNBLEACHED PULP
LOCATION H S
Washers and Screens 0.02
M. E. Evaporators 0.50
R. Boilers and D. C.
Evaporators 17 . 6
After Precipitator 17.6
Smelt Dissolving Tank 0.04
Slaker 0
Lime Kiln 1.0
After Lime Kiln
Scrubber 0.2
Flashsteam condenser 0.01

RSH
RSR,
RSSR
0.44
0.82
0.36
0.36
0.06
0
0.58
0.11
1.50
3-42
Par-
SO ticulate
2
0 0
0 0
7.10 120
7.1 6.00
0 4.0
0 Unknown
Trace 57
Trace 0.50
0 0


-------
ASSUMPTIONS
     The  following assumptions  have  been made  in developing the
     flow diagram:

     A.   PULP  MILL

         1.  Pulp Yield =  46  Percent.

         2.  Cooking  liquor charge per  air dry ton of brown stock
            equals 6,935  pounds  of  which 972  pounds are chemical
            solids.   Sulfidity equals  24 percent.

     B.   BLEACH  PLANT

         1.  Assumed  a five stage bleach plant with a chlorine
            emission of one  pound per  air dry ton of pulp.

     C.   RECOVERY
         1.   Unit operating  at  15 percent excess air at economizer
             outlet.

         2.   Particulate matter of 8 grains per SDCF leaving the
             economizer.

         3.   Efficiency of 50 percent on particulate removal in the
             direct contact  evaporators.

         4.   Steam shatter jets utilized on smelt spouts.

         5.   Design efficiency  of 97 percent for precipitator with
             an annual average  operating efficiency of 95 percent.

    D.   CAUSTICIZING

         1.   The lime kiln scrubber has been assumed at a high
             Collection efficiency/ 99 percent on lime and 80 percent on
             soda.

    E.   POWER PLANT

         1.   Excess air:  30 percent for bark, 10 percent for oil
             and 20 percent  for coal.

         2.   Bark burning equipment is a low set spreader stoker.

         3.   Reinjection from dust collector:  50 percent for bark
             and 0 percent for coal.
                                3-43

-------
                    KRAFT DIAGRAM NO. 8
                        (Continued)
E.  POWER PLANT - Continued

    4.  Design efficiencies for dust collector:   92 percent
        on bark and 95  percent on coal with annual operating
        efficiencies of 90 percent and 93 percent,  respectively.

    5.  Bark is burned 24 hours per day at a controlled rate.

    6.  Unburned combustible in refuse leaving the  dust collector
        is 40 percent.

    7.  Coal firing based on pulverized coal.
                            3-44

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
                               Dspso]
                              23,950 LBS.
                                                             850 PSIG
900 F
GJ

en
                            COAL/OIL i   BARK
                            COMBINATION BOILER.
                                    DEAERATING
                                      HEATER
                                                                                                                NOTE
                                                                                                                -**- AMPLE HOT WATER
                                                                                                                ASSUMED TO BE AVAILABLE.
                                                                                                                [  ] INDICATES FLOWS FOR
                                                                                                                PULP WILL ONLY.
                                                                                                                ALL FLOW RATES AND
                                                                                                                KILOWATTS ARE PER TON
                                                                                                                OF A.D. PULP.
                                                      1480 LBS.
                                                       [8OOJ
        X CONTINUOUS DIGESTERS,HARDWOOD, MO LIQUOR OXIDATION, DIRECT
          CONTACT EVAPORATOR RECOVERY, FJLFACHING, AND LIME KILN HIGH
          COLLECTION EFFICIENCY.
                                                                           POWER PLANT ENERGY BALANCE
                                                                              KRAFT PROCESS  NO. 8  *
                                                                                                                         EXHIBIT NO.
             SYSTEMS ANALYSIS STUDY OF
  EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
               CONTRACT NO. CPA 22-69-18
                          FOR
   DEPARTMENT OF HEALTH. EDUCATION AND WELFARE
  CONSUMER PROTECTION AND  ENVIRONMENTAL HEALTH SERVICE
      NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                                       ENVIRONMENTAL ENGINEERING, INC.
                                                                              GAINESVILLE. FLORIDA
                                J. E. SIRRINE COMPANY, ENGINEERS
                                       GREENVILLE. S. C.

-------
                          KRAFT DIAGRAM NO. 9
 TYPICAL LOCATION

      Midwestern United States.

 TYPICAL AGE OF EQUIPMENT

      Under ten years.

 GENERAL

      This flow diagram uses equipment similar to Plow Diagram No. 8
      which produces hardwood pulp, whereas No. 9 produces softwood
      pulp.  We have used similar flow diagrams, except for wood
      species, to show the increase of emissions when cooking hardwood.
      There are perhaps 30 to 40 mills in the U. S. that are illustrated
      by this flow diagram.

 EMISSIONS

      The following emissions have been selected as representative,
      based on the range of emissions presented in Chapter 4.

                      POUNDS PER AIR DRY TON OF UNBLEACHED PULP
 LOCATION


 Washers

 M. E. Evaporators

 R. Boiler and D. C.
      Evaporator

After Precipitator

 Smelt tank

 Slaker

 Lime Kiln

 Lime Kiln After
 Scrubber

 Turpentine
 Condenser
V
0.02
0.50
17.1
17.1
0.02
0
1.0
RSH,
RSR,
RSSR
0.22
0.39
0.24
0.24
0.02
0
0.6
Par-
SO ticulate
0 0
0 0
7.90 114
7.90 5
0 1



.70
.0
0 Unknown
Trace 55

0.2
0.01
0.11
0.35
Trace
0.50
                                  3-46

-------
                           KRAFT DIAGRAM NO.  9
                               (Continued)
ASSUMPTIONS
      The following assumptions have been made in developing  the
      flow diagram:

      A.   PULP MILL

          1.   Pulp Yield = 45 Percent.

          2.   Cooking liquor charge per air dry ton of brown  stock
              equals 6,996 pounds of which 996 pounds  are  chemical
              solids.  Sulfidity equals 25 percent.

      B.   BLEACH PLANT

          Similar to Flow Diagram No. 8.

      C.   RECOVERY

        ;  1.   Unit operating at 15 percent excess air  at economizer
              outlet.

          2.   Particulate matter of 8 grains per SDCF  leaving the
              economizer.

          3.   Efficiency of 50 percent on particulate  removal in the
              direct contact evaporators.

          4.   Steam shatter jets utilized on smelt spouts.

          5.   Design efficiency of 97 percent for precipitator with
              an annual average operating efficiency of 95 percent.

      D.   CAU5TICI2ING

          Similar to Flow Diagram No. 8

      E.   POWER PLANT

          1.   Excess air:  30 percent for bark,  10 percent for oil,
              and 20 percent for coal.

          2.   Bark burning equipment is a low set spreader stoker.
                                  3-47

-------
                KRAFT DIAGRAM NO. 9
                    (Continued)
3.  Reinjaction from dust collector:  50 percent for bark
    and 0 percent for coal.

4.  Design efficiencies for dust collector:  92 percent on
    bark and 95 percent on coal with annual operating
    efficiencies of 90 percent and 93 percent, respectively.

5.  Bark is burned 24 hours per day at a controlled rate.

6.  Unburned combustible in refuse leaving the dust collector
    is 40 percent.

7.  Coal firing based on pulverized coal.
                             3-48

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
                              CI5,3ICQ
                             24,250 I BS.
 I
..
CD
                                                                65 G HSIG
                                                                           9OO F
                           COAL/01 LI   BARK
                           COMBINATION BOILER
                                   DEAERATING
                                     HEATER
                                   -** AMPLE HOT WATER ASSUMED
                                   TO BE AVAILABLE.

                                   C ] INDICATES FLOWS FOR
                                   PULP MILL ONLY,

                                   ALL FLOW RATES AND
                                   KILOWATTS ARE PER TON
                                   OF A.D, PULP,
                                                  1510 LBS.
                                                   [830]
       -X- CONTINUOUS DIGESTERS, SOFTWOOD, NO LIQUOR OXIPAT ION, DIRECT
         CONTACT EVAPORATOR RECOVERY, BLEACHING, AND LIME KILN HIGH
         COLLECTION EFFICIENCY.
                                                                      POWER PLANT ENERGY  BALANCE
                                                                       KRAFT PROCESS  NO. 9 *
                                                                                                                        EXHIBIT NO.
           SYSTEMS ANALYSIS STUDY OF
EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
             CONTRACT NO. CPA 22-69-18
                        FOR
 DEPARTMENT OF HEALTH, EDUCATION AND WELFARE
CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
     NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                                      ENVIRONMENTAL ENGINEERING, INC.
                                                                             GAINESVILLE, FLORIDA
                              J. E. SIRRINE COMPANY, ENGINEERS
                                     GREENVILLE. S. C.

-------
                        KRAFT DIAGRAM NO. 10


TYPICAL LOCATION

     Southern  United States

TYPICAL AGE  OF EQUIPMENT

     1969 design;  1972 start up

GENERAL

     This flow diagram is based on production of unbleached
     softwood  kraft pulp and depicts a new mill designed with
     emphasis  on odor abatement and reduced particulate emission.
     It includes the installation of high solids multiple effect
     evaporators,  resulting in the elimination of the direct
     contact evaporator.

     Kraft Flow Diagram No. 10 represents a new mill designed
     for a production of 500 to 1000 tons per day.

EMISSIONS
     Because there are no mills in the United States operating
     at present without a direct contact evaporator, Flow Diagram
     No. 10 illustrates an imaginary mill.  Therefore, emissions
     from the recovery system have been assumed.
                 POUNDS PER AIR DRY TON OF UNBLEACHED PULP
LOCATION
Washers and Screens
Recovery Boiler

After Precipitator

Smelt Dissolving Tank
RSH
RSR
H S RSSR SO
ins 0.02 0.24 0
>rators 0.50 0.31 0
0,10 Trace 5-0
ir 0.10 Trace 5-0
Tank Trace Trace 0

P ar-
ticulate
0
0
210
2.10
0.20
                                 3-50

-------
H2S
0
Trace
Trace
0.01
RSH
RSR
RSSR
0
Trace
Trace
0.50
so2
0
Trace
Trace
0
Par-
ticulate
Unknown
25.0
0.20
0
EMISSIONS - Continued




IDCATION

Slaker

Lime Kiln

Lime Kiln Scrubber

Turpentine Condenser

ASSUMPTIONS

     The following assumptions  have been made in developing the
     Flow Diagram:

     A.   PULP  MILL

         1. Pulp Yield = 47  Percent

         2. Cooking liquor charge per air dry ton of brown stock
            equals 6,189 pounds  of which 889 pounds  are chemical
            solids.   Sulfidity equals 26 percent.

     B.   RECOVERY
         1.   Unit operating at 15 percent excess  air at economizer
             outlet.

         2.   Particulate  matter of 8  grains  per SDCF leaving the
             economizer.

         3.   No  direct  contact evaporators.

         4.   Steam shatter jets utilized on  smelt spouts.

         5.   Design efficiency of 99.5 percent for precipitator with
             an  annual  average operating efficiency of 99.0 percent.
                                      3-51

-------
C.  CAUSTICIZING

    1.  Lime kiln scrubber efficiency assumed at 99 percent
        on lime and 80 percent efficiency on soda.

D.  POWER PLANT

    1.  Excess air:  30 percent for bark, 10 percent for oil,
        and 20 percent for coal.

    2.  Bark burning equipment is  a low set spreader stoker.

    3.  Reinjection from dust collector:   50 percent for bark
        and 0 percent for coal.

    4.  Design efficiencies for dust collector:   96 percent on
        bark and 98 percent on coal with  annual  operating
        efficiencies of 94 percent and 96 percent,  respectively.

    5.  Bark is burned 24 hours per day at a controlled rate.

    6.  Unburned combustible in refuse leaving the  dust col-
        lector is 40 percent.

    7.  Coal firing based on pulverized coal.
                            3-52

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
                             [11,170]
                            I943O LBS
CM
i
                                                        850 PSIG   900 F
                          COAL/OIL I   BARK

                          COMBINATION BOILER
                                                                                                          [ ] INDICATES FLOWS FOR
                                                                                                          PULP MILL ONLY.
                                                                                                          ALL FLOWS AND KILOWATTS
                                                                                                          ARE PER TON OF AD. PULP.
                                            K70 LBS.
                                             [610]
              CONTINUOUS DIGESTERS, CONCENTRATED BLACK LIQUOR OXIDATION
              DIRECT CONTACT EVAPORATOR, NO BLEACHING, HIGH EFFICIENCY
              LIME KILN COLLECTION
                                                                       POWER PU\NT ENERGY BALANCE
                                                                          KRAFT PROCESS  NO. 10*
                                                                                                                      EXHIBIT NO.
               SYSTEMS ANALYSIS STUDY OF
    EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
                 CONTRACT NO. CPA 22-69-18
                           FOR
     DEPARTMENT OF HEALTH, EDUCATION AND WELFARE
    CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
        NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
ENVIRONMENTAL ENGINEERING, INC.
                                                                            GAINESVILLE. FLORIDA
J. E. SIRRINE COMPANY, ENGINEERS
       GREENVILLE, S. C.

-------
  3,3  NEQTRAL SULFITE SEMICHEMICAL
3.3.1  GENERAL DESCRIPTION OF NSSC

       Neutal sulfite semichemical pulping is basically a two-stage
       process.  It involves

       1,  A mild chemical treatment of the wood chips in the presence
           of a neutral chemical solution within a digester and
           followed by

       2.  A mechanical treatment, called defibering/ to disintegrate
           the wood chips into pulp.

       It derives its name "neutral sulfite" from the fact that the
       solution containing the cooking chemicals, consisting of sodium
       sulfite and sodium carbonate, is maintained above a pH of 7.0.
       The name "semichemical" is given because all of the cementing
       material is not completely removed by the chemical reaction and
       some mechanical disintegration is required to separate the fibers.
       Because some of the cementing material remains with the fibers it
       follows that the "yield" for this process is higher than for a
       conventional full-chemical pulping process.  Semichemical pulping
       may produce yields of 60 to 80 percent.

       The cooking process is carried out in either batch or continuous
       digesters,  Steam maintains the temperature and pressure of the
       cook within certain limits depending on the end use of the pulp.
       During this cooking stage odorous gases are created within the
       digester.  At the completion of the cooking cycle, residual pressure
       within the digester is used to discharge the entire contents of
       the batch digester into a blow tank.  Waste gases, containing
       the odorous compounds formed in the digester, are usually vented
       to the atmosphere.

       Before the pulp fibers can be used in the production of paper
       products the spent liquor must be washed from the pulp.  This
       washing is usually performed on multi-stage drum filters.  If
       a kraft system is adjoining, the NSSC spent liquor can be mixed
       with the spent kraft liquor, up to a limiting percentage, and
       burned in the recovery furnace.  The recovered chemicals are used
       entirely in the kraft system.  Emissions of both sulfur dioxide and
       hydrogen sulfide may be increased from the kraft recovery furnace
       when NSSC liquor is added.

       Besides the two above spent liquor systems, one discharging the
       spent liquor to sewer and the other mixing NSSC liquor with kraft
       liquor, there is a fluidized bed recovery system.  This is a patented
       system in which the NSSC spent liquor is oxidized in a reactor producing
       a pelleted product, consisting of sodium carbonate and sodium sulfate.

3.3.2  BASIC DESCRIPTION OF NSSC FLOW DIAGRAMS

       The basic assumptions which were made in the development of each
       NSSC flow diagram,  the diagram itself, and the energy balance are
       presented on the following pages.


                                    3-54

-------
                          NSSC DIAGRAM NO. 1

TYPICAL LOCATION
    Southern United States

TYPICAL AGE OF EQUIPMENT

    Five to ten years.

GENERAL

    This flow diagram is based on delivering the NSSC spent liquor
    to an adjoining kraft recovery system.  The emissions shown
    are those contributed by the NSSC operation only.  There are
    perhaps 10 to 15 mills in the U. S. illustrated by this flow
    diagram.

EMISSIONS
    The addition of NSSC liquor to a kraft recovery system lowers
    the pH of the kraft liquor.  This may result in a greater release
    of SO  and H S from the multiple effect and direct contact evapo-
    rators .

    Valid data are not available to estimate the emissions from
    the NSSC process steps.

ASSUMPTIONS

    The following assumptions have been made in developing the
    flow diagram:

    A.  RECOVERY
        1.  Unit operating at 15 percent excess air at economizer
            outlet.

        2.  Particulate matter of 8 grains per SDCF leaving the
            economizer.

        3.  Efficiency of 50 percent on particulate removal in
            the direct contact evaporators.

        4.  Steam shatter jets utilized on smelt spouts.

        5.  Design efficiency of 98 percent for precipitator with
            an annual average operating efficiency of 95  percent.
                                 3-55

-------
                   NSSC DIAGRAM NO. 1
                       (Continued)

B.  POWER PLANT

    1.  Excess air:  30 percent for bark; 10 percent for oil
        and 20 percent for coal.

    2.  Bark burning equipment is a low set spreader stoker.

    3.  Reinjection from dus:t collector:  50 percent for bark
        and 0 percent for coal.

    4.  Design efficiencies for dust collector:  92 percent on
        bark and 95 percent on coal with annual operating
        efficiencies of 90 percent and 93 percent,  respectively.

    5.  Bark is burned 24 hours per day at a controlled rate.

    6.  Unburned combustible in refuse leaving the  dust collector
        is 40 percent.

    7.  Coal firing based on pulverized coal.
                            3-56

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
             to
            00
            I/) -J
              CD
I
01
                                  [858O]
                                 I6,45O LBS.
                                                      850 PSiG
                                                                  900 F
                      33
                      cJ O
       UT

      I!
                       REC
                     BOILER
r-i m
O _i
iS> O
1^1 10
                                                    r  ' CD
                                                    O _l
   COAL /OIL I   BARK
                              COMBINATION BOILER
                                    O O
                                    K) CM
a:
                        Q
                        ^

                        3
                        O

                                      [490]
                                     930 LBS.
                                                          OLBS.
                                                           [01
                                                      [1440]
                                                      2250 LBS.
     [490]
    930 LBS.



[500]
800 KW-HR


                                                                                                           [ZI50]
                                                                                                          2150 LBS.
                                                                                 [500]
                                                                                500 LBS.
                                                                                                                     DIGESTERS
                                                                       60 PSIG
                                                                   160 PSIG
DEAERATING
HEATER
in /"
s
rO
^
                                                                       ii
                                                                       O to
                                                                       2*3
                                                   [140]
                                                  260LBS.
                                                                           in o
                                                                           OJ tf>
                                                                                                            [0]
                                                                                                         2000 LBS.
                                                                                                                      WASHING
                                                                   I5T
                                                                6000 LBS
                                                                                                          [1300]
                                                                                                          1500 L^
                                                                                                                  PAPER MACHINES
                                                                                                                    EVAPORATORS
                                                                                         0
                                                                                        ifl O
                                                                                        iP 10
NOTES:
[ J INDICATES PLOW RATES
FOR PULP MILL ONLY.

ALL FLOW RA1 5 AND
KILOWATTS ARE PER TON
OK A.D. PULP.
                                                                              POWER PLANT AUX.
                                        o'-J
                                                 10 DESUPERHEATERS
                                                    1020 LbS.
                                                     [340]
         -V  COMoiNATiCN Or NEUTRAL SULFITE SEMI-CHEMICAL
            PULPING  AND KRAFT PULPING.
                                                                            POWER PLANT  ENERGY BALANCE
                                                                                   N.S.S.C. PROCESS NO. I *
                                                                                                                              EXHIBIT NO.
                                                                SYSTEMS ANALYSIS STUDY OF
                                                    EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
                                                                  CONTRACT NO.  CPA 22-69-18
                                                                             FOR
                                                     DEPARTMENT OF HEALTH, EDUCATION AND WELFARE
                                                    CONSUMER PROTECTION AND  ENVIRONMENTAL HEALTH SERVICE
                                                         NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                                          ENVIRONMENTAL ENGINEERING, INC.
                                                                                 GAINESVILLE. FLORIDA
                                                                                   J. E. SIRRINE COMPANY, ENGINEERS
                                                                                           GREENVILLE, S. C.

-------
                          N5SC DIAGRAM NO. 2

 TYPICAL LOCATION

     Southern United States .

 TYPICAL AGE OF EQUIPMENT

     Over fifteen years.

 GENERAL

     This flow diagram is based on the use of neutral sodium sulfite,
     without chemical recovery.  Cooking is done in batch digesters.
     There are perhaps 15 to 20 mills in the U.  S.  illustrated by
     this flow diagram.

EMISSIONS
     Valid data are not available to furnish information on emissions.

ASSUMPTIONS

     The following assumptions have been made in developing the flow
     diagram:

     A.   PULP MILL

         1.  Pulp Yield =  77  Percent.

     B.   POWER PLANT

         1.  Excess  air:   30  percent for bark,  10 percent  for oil
             and  20  percent for coal.

         2,  Bark burning  equipment is a low  set spreader  stoker.

         3.  Reinjection from dust  collector:   50 percent  for bark
             and  0 percent for coal.

         4c  Design  efficiencies  for dust collector:  82 percent on
             bark and 92 percent  on coal with annual operating
             efficiencies  of  80 percent  and 90 percent, respectively.

         5.   Bark is burned 24 hours per day at a controlled rate.

         6.   Unburned combustible in refuse leaving the dust collector
             is 40 percent.

         7.   Coal  firing based on pulverized coal.
                                3-58

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
                          I5.26OLBS.
                                                      Q5O PSIG
                                                                90O F
         1/5
       ng
       o-'
       inO
       CM in
       "-JiM
V
Ui
to
                   COMBINATION BOILER



[500]
800 KW-HR

                                                                                   coO
                                                                 60 PSIG

                                                            160 PSIG
                         IS
                                       DEAERATING
                                         HEATER
                                        r- 
                                        L-J(fl'
                                                                                          [cO
                                                                                         150 LBS.
                                                                                       39
                                                                              POWER PLANT AUX.
                                                          [2100]
                                                          2IOOLBS.
                                                      S3
                                                      2o
                                                      CO O
                                                      u-J 
                                                       ID
                                                            LO]
                                                           2000 LBS..
                                                                                                         [0]
                                                                                                        6000 LBS.^
                                                                                                                  DIGESTERS
                                                                   PAPER MACHINES
                                                                                                       oo
                                                                                                       
                                              TO DESUPERHEATERS
                                                 900 LBS.
                                                 [200]
            BATCH DIGESTERS WITHOUT BLACK
            LIQUOR RECOVERY.
POWER PLANT ENERGY BALANCE
 N.S.S.C.  PROCESS  NO.  2*
                                                                                                                         EXHIBIT NO.
                                         SYSTEMS ANALYSIS STUDY OF
                              EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY

                                           CONTRACT NO. CPA 22-69-18
                                                      FOR
                               DEPARTMENT OF HEALTH, EDUCATION AND WELFARE
                              CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
                                   NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                                       ENVIRONMENTAL ENGINEERING, INC.
                                                                              GAINESVILLE, FLORIDA
                                                            J. E. SIRRINE COMPANY, ENGINEERS
                                                                    GREENVILLE, S. C.

-------
                          NSSC DIAGRAM NO. 3
 TYPICAL LOCATION

     Midwestern United States.

 TYPICAL AGE OF EQUIPMENT

     Ten to fifteen years.

 GENERAL

     This flow diagram is based on the use of neutral sodium sulfite
     with chemical recovery by the fluidized-bed process.  Cooking
     is  done in batch digesters.  There are perhaps 2 to 4 mills
     in  the U. S. which are illustrated by this flow diagram.

EMISSIONS

     Valid data are not available to present information on
     emissions except as shown on the flow diagram.

ASSUMPTIONS

     The following assumptions have been made in developing the flow
     diagram:

     A.  PULP  MILL

         1.  Pulp Yield = 77 Percent.

     B.  POWER PLANT

         1.  Excess  Air:   10 percent for oil  and 20 percent for coal.

         2.  Reinjection  from dust  collector:   0 percent.

         3.  Design  efficiencies  for dust collector:   96 percent on
            coal  with  annual operating  efficiency  of  95 percent.

         4.  Coal  firing based on pulverized  coal.

         5.  Roundwood  is  not debarked.   Bark goes  to  the digester
            with  the wood.
                                3-60

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
                                                           850 PSIG
                                                                     900
          in -
          CM o
            cr
            UJ
            CD
OJ
I
CD



[500]
800KW-HR.

                                     DEAE RATING

                                       HEATER
                                                                                     33
                           [1800]

                           1800 LBS.
                                                                                     [180]

                                                                                     300 LBS.
                           [500]

                          ,500 LBS.
                            [0]
                                                                                                    |60
                                                                                                     [aooo]
                        _

                       8
                       '-'00
                                                                                   7?
                                                                                   8
                                                                                                              DIGESTERS
                                                                                                               WASHING
                                                                                                            PAPER MACHINES
                                                                                                             EVAPORATORS
                                                                                                   )(*-
 POWER PLANT AUX.
                                   [ ] INDICATES FLOWS FOR

                                   PULP MILL ONLY.



                                   ALL FLOW RATES AND

                                   KILOWATTS ARE PER TON

                                   OF A.D. PULP.
                                                                        POWER  PLANT ENERGY BALANCE

                                                                           N.S.S.C. PROCESS NO. 3 *
                                                                                                                       EXHIBIT NO.
           * FLUIDIZEO-BED RECOVERY PROCESS.
           SYSTEMS ANALYSIS STUDY OF

EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY

             CONTRACT NO. CPA 22-69-18

                       FOR

 DEPARTMENT OF HEALTH, EDUCATION AND WELFARE

CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE

     NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                                      ENVIRONMENTAL ENGINEERING, INC.

                                                                             GAINESVILLE. FLORIDA
                              J. E. SIRRINE COMPANY, ENGINEERS
                                                                                                               GREENVILLE, 5. C.

-------
  3.4  SULFITE
3,4.1  GENERAL DESCRIPTION  OF  SULFITE PROCESS

       Sulfite pulping is an acid  chemical method of dissolving the
       lignin that bonds the cellulose  fibers together.  Many of the
       older mills use a sulfurous acid - calcium bisulfite solution
       for the cooking acid.   Calcium-base spent liquor, because of
       problems associated  with  evaporation and chemical recovery, is
       discarded and may result  in water pollution problems.  In order
       to overcome the problem of  water pollution several other acid
       bases have been developed,  the most important being sodium,
       magnesium, and ammonium.

       Because sulfite pulp is used in  a wide variety of end products,
       operations will vary considerably between mills.  These products
       can include pulp for making high grade book and bond papers,
       tissues, for combining  with other pulps, and for making dissolving
       pulp for producing cellophane, rayon, acetate, films, and others.

       The pulping operation involves cooking the wood chips in the
       presence of an acid  within  a digester.  The heat required for
       cooking is produced  by  the  direct additipn of steam to the digester
       or by the steam heating of  the recirculated acid in an external
       heat exchanger.  The cooking liquor, or acid, is made up of sulfurous
       acid and a bisulfite of one of the four above blses.  The sulfurous
       acid is usually produced  by burning sulfur or pyrites and absorbing
       the SO  in liquor.   Normally, part of the sulfurous acid is converted
       to the base bisulfite to  buffer  the cooking action.  During the
       cooking action,  it is necessary  to vent the digester occasionally
       as the pressure  rises within the digester.  These vent gases contain
       large quantities of  sulfur  dioxide and, therefore, are recovered
       for reuse into the cooking  acid.

       Upon completion  of the  cooking cycle the contents of the digester,
       consisting of  cooked chips  and spent liquor, are discharged into a
       tank.   During  this operation some water vapor and fumes escape to
       the atmosphere from  the tank vent.  The pulp then goes through a
       washing stage, where the  spent liquor is separated from the fibers.
       The washed pulp  is either shipped or kept within the plant for
       further processing.
                                      3-62

-------
       The spent liquor that was washed out of the pulp can be
       discarded or, as an alternative, can be concentrated by
       evaporation and run through a recovery cycle.   The concen-
       trated liquor is sprayed into a furnace where  the organic
       compounds are burned.  The residual inorganic  compounds
       may be collected and reused in the manufacture of cooking
       acid.
3.4.2  BASIC DESCRIPTION OF SULFITE FLOW DIAGRAMS

       The basic assumptions which were made in the development
       of each sulfite flow diagram, the diagram itself,  and the
       energy balance are presented on the following pages.
                                      3-63

-------
                             SULFITE DIAGRAM NO. 1


TYPICAL LOCATION

     Western United States.

TYPICAL AGE OF EQUIPMENT

     Over fifteen years.

GENERAL

     Sulfite Flow Diagram No. 1 is based upon the use of magnesium
     acid sulfite with chemical recovery.  Cooking is done in batch
     digesters.  There are perhaps 3 to 6 mills in the U. S. which
     are illustrated by this flow diagram.

EMISSIONS
     Because of the possible variations in this process arrangement,
     valid data are not available to provide ranges of emissions.
ASSUMPTIONS
     The following assumptions have been made in developing the
     flow diagram:

     A.  PULP MILL

         1.   Pulp Yield = 43 Percent.

         2.   Cooking Acid:  Combined SO  =  1.2 Percent
                            Free SO_     =7.3 Percent
                            Total SO     =8.5 Percent

     B.  POWER PLANT

         1.   Excess  Air:   30 percent for bark,  10 percent  for oil
             and 20  percent  for coal.

         2.   Bark burning equipment is  a low  set  spreader  stoker.

         3.   Reinjection  from dust  collector:   50 percent  for bark
             and 0 percent for coal.

         4.   Design  efficiencies  for dust collector:   82 percent on
             bark and 92  percent  on coal with annual operating
             efficiencies  of 80 percent  and 90 percent, respectively.

         5.   Bark is burned  24 hours per day at a controlled rate.

         6.   Unburned combustible in refuse leaving the dust collector
             is  40 percent.

         7.   Coal  firing based on pulverized coal.

                                 3-64

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 PAGE NOT
AVAILABLE
DIGITALLY

-------
OJ
I
CO
en
                             [I4,490J
                             20,04 OLBS.
                                                       850PSIG   300F
                            COM BIN ATI ON BOILER
                                   DEAERATING
                                     HEATER
                                                                                                            BLEACH PLANT
                                                                                                                            **
                                                                                                              DIGESTERS
                                                                                                               WASHING
                                                                                                             PULP DRYER
                                                                                                             EVAPORATORS
                                                                                                               SLAKER
                                                                                                            **- AMPLE HOT WATER
                                                                                                             ASSUMED TO BE AVAILABLE.

                                                                                                            [ ] INDICATES FLOW RATES
                                                                                                            FOR PULP MILL ONLY.

                                                                                                             ALL FLOW RATES AND
                                                                                                             KILOWATTS ARE PER TON
                                                                                                             OF A.D. PULP.
                                                I400LBS.
                                                [1070]
           *  BATCH DIGESTERS, MAGNESIUM ACID SULFITE
             WITH CHEMICAL RECOVERY AND BLEACH PLANT.
                                                                        POWER PLANT ENERGY BALANCE
                                                                         SULFITE PROCESS NO. I  *
                                                                                                                       EXHIBIT NO.
           SYSTEMS ANALYSIS STUDY OF
EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
             CONTRACT NO. CPA 22-69-18
                       FOR
 DEPARTMENT OF HEALTH, EDUCATION AND WELFARE
CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
     NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                                      ENVIRONMENTAL ENGINEERING, INC.
                                                                             GAINESVILLE. FLORIDA
                              J. E. SIRRINE COMPANY, ENGINEERS
                                     GREENVILLE. S. C.

-------
                         SULFITE DIAGRAM NO.  2

TYPICAL LOCATION

     Western United States.

TYPICAL AGE OF EQUIPMENT

     Over 15 years.

GENERAL

     Sulfite Flow Diagram No. 2 is based on the use of calcium acid
     sulfite, without chemical recovery.  Cooking is done in batch
     digesters.  There are perhaps 15 to 25 mills in the U.  S. which
     are illustrated by this flow diagram.

EMISSIONS
     Because of the possible variations in this process arrangement,
     valid data are not available to provide ranges of emissions.
ASSUMPTIONS
     The following assumptions have been made in developing the
     flow diagrams:

     A.  PULP MILL

         1.  Pulp Yield = 45 Percent

         2.  Cooking Acid:  Combined SO   =  1.25 Percent
                            Free SO,,      =  7.00 Percent
                            Total SO      =  8.25 Percent
     B.  POWER PLANT
         1.  Excess air:  30 percent for bark,  10 percent for oil
             and 20 percent for coal.

         2.  Bark burning equipment is a low set spreader stoker.

         3.  Reinjecti.on from dust collector:  50 percent for bark
             and 0 percent for coal.

         4.  Design efficiencies for dust collector:   82 percent on
             bark and 92 percent on coal with annual  operating
             efficiencies of 80 percent and 90  percent,  respectively.

         5.  Bark is burned 24 hours per day at a controlled rate.

         6.  Unburned combustible in refuse leaving the  dust collector
             is 40 percent.

         7.  Coal firing based on pulverized coal.


                                 3-66

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
                                                      6OO PSiG
                                                               66O F
       O -1
       O O
         OLU
         05
         tog
           CO
OJ
I
                   COAL/OIL!   BARK
                   COMBINATION BOILER
                           o
                                       DEAERATING
                                        HEATER



[600]
II CO KW-HR

                                                                                                      [1000]
                                                                                                      1000 LBS
                                                                60 PSIG
                                                            160 PSIG
                                                                             O o
                       in
                     39
                     o o
                     o o
                                [4500]
                                4500 LBS.
                                                                                                                BLEACH PLANT
                                                                                                  O
                                                                                                  O
                                                                                        80 LBS.
                                                                                         [20]
                                                                                       00
                                                                                                                 DIGESTERS
                                                                                                        [o]
                                                                                                       7500 LBS.
                                        PAPER MACHINES
                                                                             POWER PLANT AUX.
                                       NOTES-.

                                       KX- AMPLE HOT WATER
                                       ASSUMED TO BE AVAILABLE.
                                       [ ] INDICATES FLOWS FOR
                                       PULP WILL ONLY.

                                       ALL FLOW RATES AND
                                       KILOWATTS ARE PER TON
                                       OF A.D. PULP.
                                              TO DESUPERHEATERS
                                                  240 LBS.
                                                  [180]
              BATCH DIGESTERS, CALCIUM ACID SULFITE
              WITHOUT CHEMICAL RECOVERY BLEACH PLANT.
POWER PLANT ENERGY BALANCE
SULFITE  PROCESS  NO. 2 *
                                                                                                                        EXHIBIT NO.
               SYSTEMS ANALYSIS STUDY OF
   EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
                 CONTRACT NO. CPA 22-69-18
                           FOR
    DEPARTMENT OF HEALTH,  EDUCATION AND WELFARE
    CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
        NATIONAL AIR POLLUTION  CONTROL ADMINISTRATION
                                                                       ENVIRONMENTAL ENGINEERING, INC.
                                                                              GAINESVILLE, FLORIDA
                                 J. E. SIRRINE COMPANY, ENGINEERS
                                         GREENVILLE. S. C.

-------
                         SULFITE DIAGRAM NO. 3

TYPICAL  LOCATION

     Western United States

TYPICAL  AGE OF EQUIPMENT

     Converted to magnesium base within the past five years.

GENERAL

     Sulfite Flow Diagram No. 3 is based on the use of magnesium
     bisulfite liquor  (Magnefite), with chemical recovery.  Cooking
     is  done in batch digesters.  There are perhaps 2 to 4 mills
     in  the U. S. which are illustrated by this flow diagram.

EMISSIONS
     Because of the possible variations in the process arrangement,
     valid data are not available to provide ranges of emissions.
ASSUMPTIONS
     The following assumptions have been made in developing the flow
     diagram:

     A.  PULP MILL

         1.  Pulp Yield = 50 Percent

         2.  Cooking Liquor:  Combined SO   =  2.5 Percent.
                              Free SO,,      =  2.5 Percent
                              Total SO      =  5.0 Percent
     B.   POWER PLANT
         1.  Excess Air:   30 percent for bark,  10 percent for oil
             and 20 percent for coal.

         2.  Bark burning equipment is  a low set spreader stoker.

         3,  Reinjection  from dust collector:   50 percent for bark
             and 0 percent for coal.

         4.  Design efficiencies for dust collector:   82  percent
             on  bark and  92 percent on  coal  with annual operating
             efficiencies of 80 percent and  90  percent, respectively.

         5.  Bark is burned 24 hours per day at a controlled  rate.

         6.  Unburned combustible in  refuse  leaving the dust
             collector is 40 percent.

         7.  Coal firing  based on pulverized coal.

                                 3-68

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 PAGE NOT
AVAILABLE
DIGITALLY

-------
                             [I3.79OJ
                             I9,350LBS.
                                                        850PSIG   900 F
                               in
                             I(CD
                             O-i
                             r- O
                             o ro1
           tn
          i-a:
           CD
                     REC
                    BOILER
iI CO
O -I



                      II CO
                      O-i
                      in o
COAL/OIL [  BARK
3
o
 ~CD
__ V_
'-'VO
OJ
                            COMBINATION BOILER
                    o -1
                    Cl o
                                    DEAERATING
                                      HEATER
                                     8
                                     ^L O
                                                                                                              BLEACH PLANT
                                                                                                                             **-
                                                                                                                DIGESTERS
                                                                                                               PULP DRYER
                                                                                                               EVAPORATORS
                                                                                                                 SLAKER
                                                                                                              ** AMPLE HOT WATER
                                                                                                              ASSUMED TO BE AVAILABLE.


                                                                                                              [ ] INDICATES FLOW RATES
                                                                                                              FOR PULP MILL ONLY-

                                                                                                              ALL FLOW RATES AND
                                                                                                              KILOWATTS ARE PER TON
                                                                                                              OF A.D. PULP.
                                          TO DESUPERMEATERS
                                               I230LBS.
                                                [910]
             BATCH DIGESTERS, MAGNESIUM BISULFITE (MAGNEFITE),
             WITH CHEMICAL RECOVERY AND BLEACH PLANT.
                                             POWER PLANT  ENERGY  BALANCE
                                              SULFITE PROCESS  NO. 3 *
                                                                                                                         EXHIBIT NO.
                                                          SYSTEMS ANALYSIS STUDY OF
                                               EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY

                                                            CONTRACT NO. CPA 22-69-18
                                                                       FOR
                                                DEPARTMENT OF HEALTH, EDUCATION AND WELFARE
                                               CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
                                                    NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                                       ENVIRONMENTAL ENGINEERING, INC.
                                                                              GAINESVILLE. FLORIDA
                                                                             J. E. SIRRINE COMPANY, ENGINEERS
                                                                                    GREENVILLE, S. C.

-------
                        SULFITE DIAGRAM NO. 4

TYPICAL LOCATION
     Western United States.

TYPICAL AGE OF EQUIPMENT

     Over 15 years.

GENERAL

     Sulfite Flow Diagram No. 4 is based on the use of ammonium
     acid sulfite, with liquor incineration.  Cooking is done
     in batch digesters.  There are perhaps 1 to 4 mills in the
     U. S. which are illustrated by this flow diagram.

EMISSIONS
     Because of the possible variations in this process arrangement,
     valid data are not available to provide ranges of emissions.
ASSUMPTIONS
     The following assumptions have been made in developing the
     flow diagram:

     A.  PULP MILL

         1.  Pulp Yield = 50 Percent

         2.  Cooking Acid:  Combined SO   =  1.0 Percent
                            Free SO       =  7.0 Percent
                            Total SO      =  8.0 Percent

     B.  BLEACH PLANT

         Assumed as a three stage bleach plant.

     C.  POWER PLANT

         1.  Excess air:  30 percent for bark,  10 percent for
             oil and 20 percent for coal.

         2.  Bark burning equipment is a low set spreader stoker.

         3.  Reinjection from dust collector:  50 percent for bark
             and 0 percent for coal.

         4.  Design efficiencies for dust collector:   82 percent
             on bark and 92 percent on coal with annual operating
             efficiencies of 80 percent and 90 percent, respectively.

         5.  Bark is burned 24 hours per day at  a controlled rate.

         6.  Unburned combustible in refuse leaving the dust collector
             is 40 percent.

         7.  Coal firing based on pulverized coal.

                                  3-70

-------
 PAGE NOT
AVAILABLE
DIGITALLY

-------
                          34,340 LB:
                                                          600 PSIG   68O F
OJ
m
                    COMBINATION BOILER
                                                                                                            BLEACH PLANT
                         in
                       S3
DEAERATING
  HEATER
                                                                            POWER PLANT AUX.
                                              TO DESUPERHEATERS
                                                                                                               DIGESTERS
                                                                                                                             **
                                                                                                            PAPER MACHINES
                                                                                                             EVAPORATORS
                                                                      ** AMPLE HOT WATER
                                                                      ASSUMED TO BE AVAILABLE.

                                                                      [ ] INDICATES FLOWS FOR
                                                                      PULP MILL ONLY.

                                                                      ALL FLOW RATES AND
                                                                      KILOWATTS ARE PER TON
                                                                      OF A.O. PULP.

                                                                      I-LIQUOR INCINERATION
                                                                      WITHIN THE COMBINATION
                                                                       BOILER.
                                                   260 LBS.
                                                    [220]
                  BATCH DIGESTERS, AMMONIUM ACIDSUFITE, WITHOUT
                  CHEMICAL RECOVERY, BLEACHING, AMMONIUM LIQUOR
                  INCINERATION BLEACH PLANT.
                                                                        POWER PLANT ENERGY  BALANCE
                                                                         SULFITE  PROCESS NO. 4 *
                                                                                                                        EXHIBIT NO.
                                               SYSTEMS ANALYSIS STUDY OF
                                    EMISSIONS CONTROL IN THE WOOD PULPING INDUSTRY
                                                 CONTRACT NO. CPA 22-69-18
                                                           FOR
                                     DEPARTMENT OF HEALTH, EDUCATION AND WELFARE
                                    CONSUMER PROTECTION AND ENVIRONMENTAL HEALTH SERVICE
                                        NATIONAL AIR POLLUTION CONTROL ADMINISTRATION
                                                                       ENVIRONMENTAL ENGINEERING, INC.
                                                                              GAINESVILLE, FLORIDA
                                                                 J. E. SIRRINE COMPANY, ENGINEERS
                                                                         GREENVILLE, S. C.

-------
                          CHAPTER  4
                   QUANTITY AND NATURE OF EMISSIONS

                         TABLE OF COKTEMTS
Summary
Introduction.
Kraft Gaseous Emissions
    General
    Recovery Furnace
    Direct Contact Evaporator
    Digester Relief and Blow
    Lime Kiln
    M. E. Evaporator
    BEO Tower
    Stock Washer
    Smelt Dissolving Tank
Kraft Particulate Emissions
    General
    Recovery Furnace and DCE
    Eime Kiln
HSSC Emissions
Sulfite Emissions
Auxiliary Furnace Emissions
Summary of Emission Data
Review of Emission Standards
References
Page No.
 4-1
 4-2
 4-4
 4-4
 4-8
 4-19
 4-24
 4-30
 4-32
 4-37
 4-40
 4-42
 4-44
 4-44
 4-44
 4-46
 4-49
 4-53
 4-59
 4-61
 4-64
 4-66
                                 4-i

-------
                      CHAPTER  4     .

             QUANTITY AND NATURE OF EMISSIONS


                         SUMMARY

The control of gaseous and particulate emissions from the
various processes in  chemical wood pulping requires an under-
standing of the quantity and nature of the compounds involved.
This information is limited.  The largest amount of data is
available for the kraft process.  Because of the numerous
variables which affect emissions, it is virtually impossible
to give more than a broad range of values without monitoring
specific sources in individual mills.

For each pulping process considered in this study, both gaseous
and particulate emissions are discussed.  The nature and effects
of the compounds of interest are discussed briefly.  Then for
each source, where the information is available, the theory
of production is discussed, the operating and process variables
which affect emissions are described, an assessment of the
relative importance of the process as a source is made, ranges
of emissions for major compounds are cited, and an attempt is
made to estimate the  lowest emission which can be attained by
optimum operation.  There are numerous gaps in this format
simply because the necessary information was not available.
                              4-1

-------
  4.1  INTRODUCTION

       Planning for the control of gaseous and particulate
       emissions from various processes requires an understanding
       of the quantity and nature of the compounds involved.
       Although the wood pulping industry has been engaged in
       research efforts with respect to its air quality improve-
       ment programs for many years, valid information on emissions
       is rather sparse.  The condition is due in part to slow
       development of dependable analytical techniques.  In many
       instances, the low concentrations of gases are near the
       limit of resolution of most standard analytical techniques.
       The largest amount of information on emissions is available
       for the various modifications of the kraft process.
4.1.1  SOURCES OF DATA

       Information on the chemical nature and formation of
       particulate emissions from various pulping operations
       has been known for some time and is readily available
       in the literature.  Only in recent years, however, have
       definite studies been made to explain the production and
       identify more than broad categories of gaseous emissions.
       Although the recent literature contains some data of
       this nature, much information had to be obtained by
       direct communication.

       Quantitative emission data were obtained from the literature,
       from in-house studies, and by direct communication.
4.1.2  LIMITATIONS OF DATA

       Attempting to set forth specific quantitative values for
       emissions from a process as complicated as chemical wood
       pulping involves considerable risk.  Process and operating
       variables may have profound and sometimes unknown effects
       on emissions.  Wide and relatively rapid fluctuations may
       occur in some operating variables and in emissions.  A
       number of combinations of unit processes is possible in
       a mill to produce the same end result.  The nature and
       manner of operation of each unit process has an effect on
       the emissions from every other unit process.  In addition,
       unit processes frequently are modified from their original
       design.
                                    4-2

-------
       Only the main compounds of interest have been monitored
       although numerous others may be present.  Reliable
       analytical techniques are not available for all compounds
       of interest.  Even in those instances where so called reasonably
       reliable sampling and analytical techniques have been
       in use for some time, the actual procedure selected will
       influence the apparent concentration.

       For these reasons it is virtually impossible to give
       more than a broad range of values without monitoring
       specific sources in specific mills.
4.1.3  BENEFITS TO BE OBTAINED BY MONITORING SOURCES

       Only by monitoring individual sources in specific mills
       can reasonably reliable values be obtained for the range
       of concentration for compounds of interest. Procedures
       for such monitoring and the limitations of the procedures
       are discussed in Chapter 9.  Variations in emissions
       need to be correlated with operating variables.

       It must be realized that reliable sampling and analytical
       procedures are not available for all sources and all
       compounds which may be of interest.   Despite the limitations
       of existing analytical procedures, monitoring  of individual
       sources as an operational guide may  result not only in
       reduced emissions but in increased efficiency  of operation.
                                       4-3

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  4.2  GASEOUS EMISSIONS FROM THE KRAFT PROCESS
4.2.1  GASEOUS EMISSIONS FROM THE KRAFT PROCESS - GENERAL

       The characteristic kraft mill odor is principally due to the
       presence of a variable mixture of hydrogen sulfide,  methyl
       mercaptan, dimethyl sulfide,  and dimethyl disulfide.  All of
       these gases contain sulfur, which is a necessary component of
       the kraft cooking liquor.  Hydrogen sulfide,  methyl  mercaptan,
       dimethyl sulfide, and dimethyl disulfide are  referred to as
       reduced sulfur compounds, and the latter three gases are usually
       described as organosulfur compounds.

       Hydrogen sulfide emissions are derived from breakdown of the
       weak base, sodium sulfide, which is the characteristic of kraft
       cooking liquor.  It may also  be generated by  improper operation
       of a recovery furnace.  Methyl mercaptan and  dimethyl sulfide
       are formed in reactions with  the wood component lignin.
       Dimethyl disulfide is formed  through the oxidation of mercaptan
       groups derived from the thiolignins.

       A great deal of variability exists in the published  values
       of the odor thresholds for these sulfur gases, as can be seen
       in Table 4-1.   The detection  of these gases by the olfactory
       senses is obviously a highly  individualistic  determination.

       Table 4.2 presents some of the physical properties of these
       sulfur gases.

       Sulfur Dioxide (SO_)    _ .. _       . ,    .   .     .  ,_,  ,
       	2 .  Sulfur dioxide emissions in the kraft
       process result from oxidation of reduced sulfur compounds.   A
       potential source of sulfur dioxide is the recovery boilers,
       where reduced  sulfur gases present can be oxidized in the
       furnace atmosphere.

       Sulfur dioxide is a mildly acidic gas and is  readily absorbed
       by the alkaline black liquor  in the direct contact evaporator.
       The mechanism  is an acid-base reaction:

           SO   +  2NaOH    Na SO    +  HO               Eq.  4.la
             4U                  ^i J      ^

           Na SO   +   SO   +  HO   J   2NaHSO             Eq.  4.1b

       This reaction  will, of course,  result in a lowering  of the pH
       of the liquor,  because of the reduction in free alkali.
                                       4-4

-------
                          TABLE  4-1

                ODOR THRESHOLDS OF KRAFT MILL GASEOUS
                        SULFUR COMPOUNDS IN AIR

                            ppm  (by volume)
Sulfur Dioxide    1.0-5.0   (2)

Hydrogen Sulfide  0.0085    (_!) ,

Methyl Mercaptan  0.0021    (2) ,

Dimethyl Sulfide  0.0001    (2),
               0.0047   (2),  0.0009   (4)

               0.040    (3),  0.0006   (_4)

               0.0036   (3),  0.0003   (4)
                          TABLE  4-2

                CHARACTERISTICS OF KRAFT MILL GASEOUS
                           SULFUR COMPOUNDS
   Compound
  Characteristic
       Odor
        Explosive Limits  (air)
Color   Lower   Upper
Sulfur Dioxide

Hydrogen Sulfide

Methyl Mercaptan

Dimethyl Sulfide
strong, suffocating   none

rotten eggs           none

rotten cabbage        none

vegetable sulfide     none
          Not-explosive

        4.3%    46%  (5)

        3.9%    22%  (6)

        2.2%     9%  (6)
                                4-5

-------
The principal potential sources of sulfur dioxide in the kraft
mill  are  the power boilers and the recovery furnace.  Emissions
from  the  power boilers depend upon the type of fuel and the
sulfur  content of the fuel.  With a 2 percent sulfur fuel oil,
the sulfur dioxide emissions range from 12 - 43 Ib/ADT of pulp;
for a 2 percent  sulfur coal, the emissions range from 15 - 57
Ib/ADT  of pulp.  The sulfur dioxide emissions from the recovery
furnace range from 0.5 - 15 Ib/ADT of pulp.

Hydrogen  Sulfide (HS) .  TT ,        -,,-.-,.    ^  i_i    -j-
      	2     Hydrogen sulfide is a feebly acidic gas
which partially  ionizes in aqueous solution.  The ionization pro-
ceeds in  two stages with the formation of hydrosulfide and, with
increasing pH, sulfide ions

    H S   +   HS~  +  H+    +   S~  +  2H+           Eq. 4.2
                 increasing pH ->

Black liquor contains a high concentration of dissolved sodium
sulfide in strongly alkaline solution.  If the pH were depressed,
the sodium sulfide would hydrolyze to sodium hyrosulfide and
below pH  8 appreciable unionized hydrogen sulfide would form as
the reaction equilibria in Eq. 4.2 moves from right to left.  Shih
(28)  reports that at a pH of about 8.0, most hydrogen sulfide forms
hydrosulfide ions, so in normal black liquor conditions, there is
very  little dissolved hydrogen sulfide in the liquor.

Due to  the equilibrium between the hydrosulfide ion and water
vapor,  hydrogen  sulfide gas can be stripped from black liquor at
steam vents.  There could be, therefore, a problem in the evapo-
rator areas of the kraft mill.

Hydrogen  sulfide is formed in the recovery furnace in the reducing
atmosphere found in the lower sections, as the sulfur containing
compounds from the black liquor are volatilized and reduced.  How-
ever, in normal  furnace operation the hydrogen sulfide oxidizes to
sulfur  dioxide (which is largely absorbed within the furnace)  in
the combustion sections  before the exhaust  gases  leave  the
furnace.

Hydrogen  sulfide generally represents the largest gaseous emission
from  the kraft process.   Two of the most effective means for reduc-
ing the hydrogen sulfide emissions from kraft mills are black liquor
oxidation and maintaining tight control of critical process operating
variables.
                                 4-6

-------
 Methyl Mercaptan (MeSH).   Methyl mercaptan  is a reduced sulfur
 compound which  is  formed  during the kraft cook by the reaction
 of hydrosulfide ion  and the methoxy-lignin  component of the
 wood  (8) :

    Lignin-OCH   +  HS~   *    MeSH  +  Lignin-cf      Eq. 4.3


 Methyl mercaptan will also dissociate in an aqueous solution to
 methyl mercaptide  ion.  Shah  (9) has reported that this dis-
 sociation is essentially  completed above a  pH of 12.0:

    MeSH  +  OH  -  MeS~ +  HOH                      Eq. 4.4

 Methyl mercaptan will, therefore, be present in low concentra-
 tions as a dissolved gas  in the black liquor.  As the pH decreases,
 the equilibrium shown above shifts to the left and MeSH gas is
 evolved.

 Methyl mercaptan is primarily emitted from  the digester relief and
 blow where it is formed,  and from the brown stock washers where
 the pH of the liquor drops below the equilibrium point.  Its
 emission1 decreases as its residual concentration in the liquor
 diminishes.

 Dimethyl Sulfide and Dimethyl Disulfide (MeSMe, MeSSMe). Dimethyl
 sulfide is primarily formed through the reaction of methyl mercaptide
 ion with the methoxy-lignin component of the wood (8).  It does not,
 however, dissociate as hydrogen sulfide and methyl mercaptan do:

    Lignin-OCH   +  MeS~   -  Lignin-0   +  MeSMe       Eq. 4.5

 Dimethyl sulfide may also be formed by the disproportionation of
methyl mercaptan.  At normal liquor temperatures (150 - 200F) it
 is highly volatile.

Dimethyl disulfide is formed by the oxidation of methyl mercaptan
 throughout the recovery system, especially in oxidation towers.
Dimethyl disulfide has a higher boiling point than any of the
other compounds and its retention in the liquor is therefore greater
than the other organosulfur compounds.

    4MeSH  +  O    +   2MeSSMe  +  2H O                Eq. 4.6
                                       4-7

-------
  4.2.2  GASEOUS EMISSIONS FROM THE KRAFT RECOVERY FURNACE

4.2.2.1  Formation of Gaseous Pollutants

         The purposes of burning concentrated black liquor
         in the kraft recovery furnace are:  the recovery of
         sodium and sulfur, the production of steam, and the
         disposal of unwanted dissolved wood components in
         the liquor.  In most instances, liquor of 62% solids
         content or greater will burn in a self-supporting
         combustion.  Sodium and sulfur can be recovered in
         the form of sodium sulfide and sodium carbonate.

         The recovery furnace theoretically is divided into
         three sections:  the drying and pyrolysis zone,
         the reducing zone, and the oxidizing zone.  The
         black liquor is intorduced to the furnace through
         spray guns located in the drying zone.  The
         heat in the furnace is sufficient to immediately
         evaporate the remaining water from the liquor and
         to cause the organic solids within the liquor to under-
         go pyrolysis.  Pyrolysis is defined as the chemical
         change brought about by the action of heat upon a
         substance.

         Pyrolysis occurs in the drying zone of the furnace.
         The drying zone of most recovery furnaces is in a
         combined oxidation and reduction state because of
         the manner in which the primary air is introduced
         into the furnace.   Forced  draft fans force the primary
         air into the furnace through the air ports located
         around the perimeter of the furnace at the level of
         the drying zone.

         It is felt that sulfur which exists in organic substances
         undergoing pyrolysis  in the oxidizing atmosphere will
         usually be oxidized to form nonvolatile sulfur radicals
         such as sulfite, thiosulfate,  and sulfate (10).  These
         non-volatile sulfur radicals in the form of sodium salts
         will fall into the reducing zone of the furnace, although
         small particles may be carried out of the furnace by the
         draft of the fan.
                                4-8

-------
            Flue
            Gas
              Air
         Black Liquor
              Air-
                                               OXIDIZING
X
                                               DRYING
X
                                               REDUCING
             Smelt
FIGURE 4-1  SHOWING THE PRINCIPAL SECTIONS AND LOCATIONS OF

            AIR INLETS FOR A TYPICAL RECOVERY FURNACE
                             4-9

-------
         Conversely, sulfur which exists in organic substances under-
         going pryolysis in a reducing atmosphere/ may form volatile
         reduced sulfur compounds (10).  These gases flow into the
         upper regions of the furnace.

         These proposals exist only as theory, and much work remains
         to be done in understanding the mechanism of pyrolysis of
         black liquor before these theories can be regarded as correct.

         The sodium salts of the oxidized sulfur compounds which have
         fallen into the reducing zone along with the carbon ash residue
         will undergo reduction to sodium sulfide and sodium carbonate.
         Carbon dioxide and carbon monoxide are gaseous by-products
         of these reduction processes.  The fused sodium sulfide and
         sodium carbonate are withdrawn and mixed with water in the
         smelt tank to form green liquor.

         The total reduced sulfur (TRS)  gases and the carbon monoxide
         which are drawn into the oxidizing zone of the furnace should
         undergo oxidation to sulfur dioxide, carbon dioxide, and water
         This oxidation will>be carried to completion-if proper conditions
         of temperature, excess oxygen,  residence time and turbulence
         are provided.  When these conditions do not exist, complete
         oxidation will not occur and the reduced sulfur compounds will
         escape from the furnace.


4.2.2.2  Effect of Operating Variables upon Emissions from the
         Recovery Furnace

         There are many operating variables which have been shown to
         affect the emissions  from a kraft recovery furnace.  Several
         of those which are considered to be the most important and
         which are understood the best are:  the rate at which black
         liquor is fired into the furnace, the ratio of secondary
         air to the black liquor firing rate, the percent excess oxygen
         in the furnace flue gas, black liquor spray droplet size, and
         turbulence within the recovery furnace.

         Several authors have identified the relationship which
         exists between the firing rate of a furnace and the
         gaseous emissions (10, 11,  12,  13).  Figure 4-2 shows
         the relationship between the firing rate and the
         hydrogen sulfide emissions  from a particular recovery
         furnace.  The hydrogen sulfide emissions gradually
         increase until a sharp upward break occurs.  The
         point at which this sharp increase occurs is primarily
         dependant upon the capacity of the forced draft fan.

-------
                         FIGURE 4-2



         THE EFFECT OF OVERLOADING A KRAFT RECOVERY



        FURNACE UPON HYDROGEN SULFIDE EMISSIONS
600 - 
400  -
200 '
     100
             120



PERCENT OF RATED CAPACITY




            4-11
                                                         140

-------
The other operating variables discussed in this section are
important in determining the rate at which the emissions
will increase with overloading.

The I.D. fans installed on a furnace are usually conser-
vatively designed and can handle small increases in the
black liquor firing rate which are required during peak
loading.  However, a point will be reached when the fan
is at its limiting capacity and it will no longer be
able to provide sufficient oxygen to oxidize the rising
gases (10).  In addition, secondary air will not be introduced
at a rate sufficient to provide adequate mixing to thoroughly
oxidize the gases.  Increasing the capacity of the fan will
not solve the problem totally.  As the air flow within the
furnace is increased, carry-over of black liquor droplets will
occur.  These particles will burn in the upper sections
of the furnace, generating excessive heat which may result in
superheater tube failure.

The increased hydrogen sulfide emission of an overloaded
furnace is therefore partially caused by the poor gas flow
characteristics and lack of oxygen within the oxidizing zone
of the furnace, both of which are required to maintain minimum
emissions.

It has also been shown that to maintain minimum reduced
sulfur emissions from a recovery furnace the percent of
excess oxygen in the recovery flue gas must be maintained
above a minimum level (10).  The presence of sufficient
excess oxygen does not, however> insure minimal emissions
unless certain conditions exist in the furnace:  the
efficient mixing of the available oxygen with the combustible
material, a temperature high enough to provide rapid chemical
reaction, and sufficient residence time to allow oxidation
to occur.  Murray and Rayner (10)  have experimentally
determined in the laboratory the relationship between the
percent excess oxygen in the flue gas and the hydrogen
sulfide emissions as shown in Figure 4-3.  Thoen (13)  has
also derived similar relationships, but the percent excess
oxygen required for a particular furnace must be experimentally
determined for each case.  Most authors have reported that
minimum TRS emissions occur when oxygen in the flue gas from
the recovery furnace is about 2.5 - 4.0 percent by volume.
                                 4-12

-------
                                       FIGURE  4-3




                THE EFFECT OF  RESIDUAL OXYGEN IN THE FLUE GAS



                    UPON HYDROGEN  SULFIDE EMISSIONS
    600 . .
    400
J
\


3.
u
u
D




S
    200. .
                                          CORRELATION COEFFICIENT = 0.606
        2.0
2.5          3.0          3.5



      OXYGEN IN FLUE GAS  (%)



                 4-13
                                                              4.0
                                                      4.5

-------
The ratio of the secondary air flow rate to the black liquor
firing rate is also an important variable.  At the ratio which
yields the lowest emissions, the excess oxygen requirement
is usually satisfied  (10, 13).  Murray and Rayner's relation-
ship of this ratio versus the hydrogen sulfide emissions is
shown in Figure 4-4.  Results by other authors show that the
secondary air should amount to about 30 - 40 percent of the
air supplied to the furnace.

Thoen (13) has reported that when black liquor is sprayed
into the furnace in small drops there exists a tendency for
the solids to be carried up to the oxidizing zone immediately,
whereas larger spray droplets will fall to the bottom of the
furnace.  When black liquor is carried to the upper zones it
will burn slowly/ yielding excessive amounts of heat which
will overheat the boiler.  The products of combustion will
then be swept out of the furnace before they can be oxidized
and emissions of TRS gases will be increased.  Thoen has
given TRS emission values (Table 4-3) for "coarse" and
"fine" sprays which show about a 1000 percent increase between
the two.  Unfortunately the sizes of the coarse and fine spray
droplets were not reported, but the nozzle sizes, line pressures
and temperatures corresponding to the coarse and fine spray
conditions are shown in Table 4-3.  The size of the spray
droplets can be controlled by the temperature and pressure
of spraying the liquor and by the type of spray nozzles.

The turbulence created by the introduction of the secondary
air is of great importance.  Turbulence creates thorough
mixing and thus more efficient oxidation of the gases.  A
well designed introduction system for the secondary air
will provide a high degree of turbulence while imparting
no vertical velocity to decrease residence time.  The more
common methods of injection are horizontally and tangentially
arranged inlet ports.

The channeling of the reducing atmosphere into the upper
regions of the furnace has two effects.  First it allows
an increased period of contact between sulfur containing
organic solids and the reducing atmosphere which will lead
to further reduced sulfur emissions.  Secondly, it will
decrease the efficiency of the oxidizing zone of the furnace.
Channeling can be easily controlled by proper introduction
of secondary air to create turbulence to mix the oxygen
with the reducing atmosphere.
                             4-14

-------
                                    FIGURE  4-4



               THE EFFECT OF THE SECONDARY AIR/BLACK LIQUOR FIRING



                 RATE RATIO UPON HYDROGEN  SULFIDE EMISSIONS
    600 - 
    400
en
a.
EL.
h

en
    200 -.
                                                CORRELATION COEFFICIENT = 0.755
                                4-
        2.4
             2.8                      3.2




SECONDARY AIR TO FURNACE  (Ibs./lbs.  solids)




                   4-15
                                                                                  3.6

-------
To date it has not been shown experimentally that there is
a relationship between the sulfide ion concentration in the
black liquor and the quantity of gaseous emission of any
compound from the recovery furnace itself.  Thus any decrease
in emissions from the furnace itself while burning oxidized
black liquor as opposed to unoxidized liquor is purely
coincindental.  The effect of oxidized and unoxidized liquor on
reduced sulfur emissions shows up in the direct contact evapo-
rator following following the recovery furnace, where emissions
will be decreased if the liquor is oxidized.

Th,e wide variety of recovery furnace designs makes it impossible
to present data which can be considered to be typical for
every furnace.  The data and figures presented in this section
are given to show trends which have been observed on selected
furnaces.
                          TABLE  4-3

                  THE EFFECT OF SPRAY SIZE ON SULFUR
                  GAS EMISSIONS FROM A KRAFT RECOVERY
              FURANCE*(13) (USING UNOXIDIZED BLACK LIQUOR)
                        Flue Gas Concentration (ppm)

                SO      H S      MeSH      MeSMe      MeSSMe

Coarse Spray    2.120.02      0          0          0

Fine Spray     10.70    2.40      0.12       0          0.03


*These data are representative of a particular furnace only.

Note:  Coarse Spray - No. 4 Nozzle at 17 psi and 240F

       Fine Spray - No. 2 Nozzle at 17 psi and 245F
                                 4-16

-------
4.2.2.3  Relative Importance of the Recovery Furnace
         The importance of the kraft recovery furnace as  a source
         of emissions is dependent upon the operation of  the  furnace
         itself.   As  has been described in this  section,  there  exists
         an optimum set of operating conditions  for each  furnace
         which will result in the reduction of the  emissions  of
         reduced  sulfur compounds to a negligible level.   If  the
         furnace  is operated at conditions other than optimum,
         the quantity of emissions will increase as the divergence
         from the optimum condition, increases.  The kraft recovery
         furnace  may  then become the major source of sulfurous
         emissions in the mill.
4.2.2.4  Ranges  of Emissions  of Gaseous  Sulfur Compounds

         The  importance of the operating variables  has  been
         determined.   In general,  recovery furnaces are rarely
         operated under optimum conditions.   The ranges of emissions
         in Table 4-4 typify  the emission ranges for kraft recovery
         furnaces operating under non-optimum conditions.   Variances
         from these ranges may occur if  the furnace is  operated
         under severe operating conditions.   Operation  under optimum
         conditions is discussed in the  following section.
                                   T  A B L E   4-4

                       APPROXIMATE  RANGES OF  EMISSIONS  FROM KRAFT
                                   RECOVERY  FURNACES
                          (Before the Direct  Contact Evaporator)

                                          lb/ADT Of pulp

              Sulfur Dioxide               10.0 - 15.0

              Hydrogen Sulfide             1.0 -  5.0

              Methyl Mercaptan             0.01-  0.10

              Dimethyl Sulfide             0.01-  0.02

              Dimethyl Disulfide            0.01-  0.02
                                         4-17

-------
4.2.2.5  Emissions Under Optimum Conditions

         A kraft recovery furnace which is operated at optimum
         operating conditions which have been individually
         determined for the furnace in question can be expected
         to emit negligible amounts of gaseous sulfur compounds.

         In his study of the effects of operating conditions
         upon emissions from the furnace, Theon (13) , operated
         a recovery furnace under optimum conditions for a
         24 hour period, and obtained the results in Table 4-5.
                          TABLE  4-5

                        KRAFT RECOVERY FURNACE
                EXTENDED OPERATION AT OPTIMUM CONDITIONS* (13)
                                (24hr)

                            (load-116% design)


                   	ppro v/v 	    	%	
Periodic Samples   SO     H s   RSH   RSR   RSSR    O    CO     CO

      1            0.04    0000      3.1  15.6   0
      2            0.07    0000      4.4  15.4   0
      3            0.04    0000      4.4  15.4   0
      4            0.01    0000      4.8  15.4   0
      5            0,08    0000      2.1  16.4   0
*35% secondary air at 180 ft/sec; coarse black liquor spray.

Note:  (1)  0 indicates concentration less than detection limits of
            analytical equipment.

       (2)  Work currently under way indicates the sulfur dioxide
            concentrations presented in this table may be low due
            to the limitations of the analytical techniques used.
                                  4-18

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4.2.3  GASEOUS EMISSIONS FROM THE DIRECT CONTACT EVAPORATOR

2.3.1  Formation of Gaseous Pollutants

      Gaseous emissions from the direct contact evaporator are caused
      by the stripping of the dissolved gases from the black liquor by
      the furnace flue gases.  This occurs when a concentration differ-
      ence exists between the actual concentration of the gases in the
      flue gas and the equilibrium concentration which is consistent
      with the temperature and pH of the liquor (14).  In black liquor,
      the dissolved hydrogen sulfide and methyl mercaptan are normally
      low, as discussed in Section 4.2.1.  However, the absorption of
      carbon dioxide and sulfur dioxide from the flue gas reduces the
      pH of the liquor causing an increase in the concentrations of
      these dissolved gases.  This point will be elaborated upon shortly.
      Dimethyl sulfide and dimethyl disulfide usually have low residual
      concentrations in the unoxidized liquor and their emission from
      this source is characteristically low.  The concentrations of these
      two gases in oxidized liquor is usually slightly higher (especially
      dimethyl disulfide) and the emissions may be slightly greater than
      for unoxidized liquor.

      The absorption of carbon dioxide and sulfur dioxide takes place
      according to the straightforward acid-base equilibrium reactions:
          OH   +  C0         H  H+  +  C0=                Eq. 4.7
          OH   + .S02        H  H+  +  S03=                Eq. 4.8


      In the case of black liquor, the carbonate and sulfite ions are
      both stronger acids than hydrosulfide and mercaptide 'ions and will
      displace the latter ions from the liquor.  The acid hydrogen ions
      formed by the absorption of these gases will enter into competitive
      reactions between hydrosulfide, mercaptide and hydroxide ions in
      the liquor:

          H   +  HS~   +   H2S*                            Eq' 4'9

          H'  4-  RS~   J   RSHt                            Eq. 4.10


          HT  +  OH~   +   HO                             Eq. 4.11

      In actuality, all three reactions take place.  The proportion of
      the ion which enters into each reaction will depend upon the
      relative strengths of the negative ions listed and the concentra-
      tions of the ions .
                                        4-19

-------
         Most of the hydrogen ion will probably react with the
         hydroxide ion to lowejT the pH of the solution.  This
         shift in equilibrium Will cause an increase in the
         dissolved concentration of hydrogen sulfide and methyl
         mercaptan gases in th.0 liquor, and the reactions which
         take place in Eq. 4-9 and 4.10 will tend to increase
         emissions from the evaporator.  The escaping vapor may
         also serve as a vehicle for hydrogen sulfide and methyl
         mercaptan stripping.


4.2.3.2  Effect of Operating Variables Upon Emissions from the
         Direct Contact Evaporator

         For a given concentration of a dissolved gas in the
         black liquor, there exists an equilibrium concentration
         of that compotuxd in trie gas above the liquor, which is
         consistent with the temperature and the pressure of the
         system.  According to the principles of mass transer, a
         transfer of mass froiti the liquor to the gas phase will
         occur if the concentration of the gas is lower than the
         equilibrium concentration.

         Conversely,  mass transfer will occur from the gas to the
         liquor if the concentration in this gas phase is greater
         than the equilibrium concentration.

         Murray and Eayner (13)  have developed a mathematical model
         which approximates  the  actual conditions for hydrogen
         sulfide transfer-   Their  formula shows that the equilibrium
         concentration, of hydrogen sulfide above the liquor is de-
         pendent upon the sulfide  ion concentration and the pH of the
         liquor.   The mathematical model for the mass transfer of
         hydrogen sulficle is Dependent upon this equilibrium concen-
         tration and  the  concentration of hydrogen sulfide in the
         entering gas stream as  well as the gas flow rate.  Tables
         4-6  and 4-7  show the effect of pH and sulfide concentration
         upon the emission of hydrogen sulfide from the direct contact
         evaporator.   The datei are taken from the pilot plant work
         under controlled conditions

         A  similar  mathematical  model  could be developed for methyl
         mercaptan.   Dimethyl sulfide  and dimethyl disulfide do not
         dissociate  in blacK liquor and their removal from the liquor
         is a function of their  vapor  pressures and the temperature
         of the  liquor, rathet than a  function of the pH.
                                   4-20

-------
                     TABLE  4-6

   THE EFFECT OF CHANGING THE pH OF THE BLACK LIQUOR
      ON HYDROGEN SULFIDE EMISSIONS DURING DIRECT
               CONTACT EVAPORATION (14)

                  (Pilot Plant Study)

12.59
12.33
12.07
Na S Cone
in Black
Liquor
(g/i.)
14.2
18.3
15.3
H S Cone
in Recovery
Furnace
Flue Gases
(ug/l.)
16
41
36
H S Cone
in Contact
Evaporator
Exit Gas
(yg/1.)
53
185
273
Change in H i
Across Contact
Evaporator
(P/I.)
r
37
144 ;
237
                     TABLE  4-7

THE EFFECT OF CHANGING THE SODIUM SULFIDE CONCENTRATION BY
   OXIDATION ON THE EMISSION OF HYDROGEN SULFIDE DURING
               CONTACT EVAPORATION (14)

                  (Pilot Plant Study)
Na S Cone
in Black
Liquor
PH (g/1.)
11.85 28.4
20.2
Zero
12.30 33.3
18.3
Zero
H S Cone
in Recovery
Furnace
Flue Gases
(yg/i.)
204
Zero
74
32
41
14
H S Cone
in Contace
Evaporator
Exit Gas
(yg/1.)
580
216
50
295
186
'10
Change in H S
Across Contact
Evaporator
(w/i.)
376
216
- 24
263
145
- 4
                              4-21

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          It should be  noted  that if black liquor oxidation is
          performed to  a  residual sulfide concentration of less
          than 0.1  gm/liter,  the pH of the liquor is no longer
          a factor  in emissions from the direct contact evaporator.
 4.2.3.3   Relative  Importance of the Direct Contact Evaporator

          The  significance of the direct contact evaporator as
          an emissions source is dependent upon the residual
          sodium sulfide concentration and the pH of the black
          liquor being handled.  Hydrogen sulfide emissions have
          been observed to increase rapidly with increasing
          sodium sulfide residual concentrations in black liquor.
          High sodium sulfide concentrations in black liquor may
          result in the direct contact evaporator becoming a
          major source of emissions.  When emissions are high,
          the hydrogen sulfide emissions may be decreased by
          maintaining a higher pH.

          Complete  oxidation (99+ percent) of kraft black liquor
          to produce a negligible sodium sulfide concentration
          will virtually eliminate the direct contact evaporator
          as a major emission source within the kraft mill.
4.2.3.4  Ranges of Emissions of Gaseous Sulfur Compounds

         Because of the importance of the sodium sulfide con-
         centration upon the emission of hydrogen sulfide and
         methyl mercaptan, ranges of emissions for both oxidized
         and unoxidized liquor have been tabulated.  The ranges
         of emissions in Table 4-8 represent the sum of the
         recovery furnace and direct contact evaporator contri-
         butions, and do not separate the increase in emissions
         across the direct contact evaporator from the portion
         that may enter with the recovery furnace gases.
4.2.3.5  Emissions under Optimum Conditions

         From the very low reduced sulfur emissions from a
         modern recovery furnace operated under optimum con-
         ditions, it is concluded that the emissions from a
         direct contact evaporator are primarily dependent
         upon the degree of black liquor oxidation.  At 99+
         percent oxidation efficiency, the emissions should be of the
         be of the order of 0.5 Ib/ADT.


                                    4-22

-------
        If high residual sulfide concentrations remain in the
        liquor during evaporation, the emissions can be controlled
        to a limited extent by maintaining the pH as high as is
        feasible.
                            TABLE  4-8

           APPROXIMATE RANGES OF EMISSIONS FROM THE DIRECT
                         CONTACT EVAPORATOR
                                       UNOXIDIZED LIQUOR      OXIDIZED LIQUOR
                                           (Ib/ADT)              (Ib/ADT)

Sulfur Dioxide                             2.0 - 8.0            2.0 - 8.0

Hydrogen Sulfide                           5.0-30.0           0.10-2.0

Methyl Mercaptan                           0.50 - 2.50          0.05 - 0.25

Dimethyl Sulfide                           0.10 - 0.30          0.01 r 0.10

Dimethyl Disulfide                         0.10 - 0.40          0.01 - 0.20
                                     4-23

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  4.2.4  GASEOUS EMISSIONS FROM THE DIGESTER RELIEF AND BLOW
4.2.4.1  Formation of Gaseous Pollutants

         In a digester, chips are treated with predetermined quantities
         of alkali, in the form of caustic sulfide liquors,  and subjected
         to heat and pressure to separate fibrous constituents of wood
         by dissolving the nonfibrous constituents (15).   Digester "relief
         is an essential part of [Batch] digester operation; it is done
         for four purposes:  circulation, control of cooking, reduction
         of digester pressure before blowing and removal  of air. . .(16)."
         In some cases the gases which are relieved from  the digesterlnay
         be vented to a turpentine recovery system where  the crude turpen-
         tine is condensed.  Noncondensibles in the relief gases will
         pass through the turpentine condenser and are a  possible source
         of emissions at this point unless further processing of them
         is arranged.  When a turpentine recovery system  is  not used,
         the relief gases are sent to a heat recovery system, after
         which the noncondensible gases represent a potential emission
         problem.  When the cook is completed, the contents  of the
         digester are blown into the blow tank by the pressure within
         the digester.  "The contents are blown tangentially into the
         top of the blow tank,  the stock dropping into the tank and the
         steam and gases escaping from the top vent (IT)."  The steam
         and gases pass through a heat accumulator from where they may
         be emitted to the atmosphere.

         The hydrolytic equilibria for the sulfide ions in the kraft
         liquor are:

               S  -  +  HOH 1 HS~  +  OH~                     Eq.  4.12

               HS~ +  HOH +2 H S  -f  OH~                     Eq.  4.13

         While  previous  work indicates  that in kraft pulping,  the
         equilibrium  for Equation 4.13  lies  almost completely  to the
         left,  reliable  values  for  the  equilibrium constant  for Equation
         4.12 are  not available.  However,  K..  is  known to be large,  and
         it  is  proper to express  the total sulfur in the  liquor as
        hydrosulfide  ion (HS~)  (8).

        The demethylation of lignin is  believed  to  be accomplished
        by a nucleophlic attack  by  the  hydrosulfide ions upon the
        methoxyl  group  of the  lignin.   In a consecutive  bimolecular
        reaction  the mercaptide  ion attacks another methoxyl  group
        and yields dimethyl  sulfide  (8).
                                     4-24

-------
              Lignin-OMe  +  HS  - MeSH + Lignin-O           Eq. 4.14

              MeSH  +  OH~  -> Mes"  +  HOH                   Eq. 4.15

              Lignin-OMe  +  MeS~ '  "*" MeSMe  + Lignin-O~     Eq. 4.16
      Thus since the methyl mercaptan  concentration increases as
      a  consequence of the reaction in Eq.  4.14,  the rate of reaction
      4.16 likewise increases, which tends  to deplete mercaptan by
      conversion to dimethyl sulfide.

      Ultimately, a steady state condition  may be reached at which
      the mercaptan is formed and depleted  at equal rates,  and its
      concentration will remain constant.   On the other hand the
      rate of dimethyl sulfide formation should be zero at  the
      outset of the cook and gradually increase,  approaching a steady
      rate of formation at steady state condition (see Figure 4-5)  (8).

      There are some side reactions which can occur during  a cook.
      One is the oxidation of methyl mercaptan to dimethyl  disulfide  (8):

              2RSH  +  1/2 0   -  RSSR + HO                 Eq.  4.17

      It is conceivable that by eliminating oxygen from the system, this
      side reaction producing a malodorous  gas could be suppressed.

      Another side reaction which may  be significant is the dispropor-
      tionation of methyl mercaptan to dimethyl sulfide and hydrogen
      sulfide (8) .  This reaction has  been  found  to have a  slow
      but significant rate:

              2RSH  -  RSR + H S                             Eq.  4.18

4J2.4.2 The Effect of Operating Variables Upon Emissions

      McKean, Norwicki and Douglass have stated that minimum black
      liquor recycle, short duration cooks, low cooking liquor
      sulfidity and high residual alkali will help yield minimal
      emissions from the kraft digester.  However these authors differ
      in their opinion of the effect of temperature in the  digester
      upon emissions.

      In the following paragraphs the  relationships between various
      operating variables and emissions are discussed.  It  must be
      remembered, however, that practical verification has  not been
      reported in many instances between the relationships  established
      and variations in pulp quality produced under these conditions.
      In other words, it frequently is not  possible to optimize operating
      conditions to produce minimum emissions and still produce pulp
      of the desired quality.

                                    4-25

-------
en
a)
r-l
O
e
o
M
EH
EH
3
8
                                        FIGURE 4-5


                       THE RATE OF FORMATION OF METHYL MERCAPTAN AND

                       DIMETHYL SULFIDE DURING DIGESTION  AT 180 C
      0.014--
      0.012..
      0.010'
                                                                            RSR
      0.008
      0.006
      0.004
      0.002-
                                                                              RSH
                                        TIME (hours)
                                             4-26

-------
Effect of Wood Species on Odor Formation.  Investigations into
the quantitative amounts of.gaseous products from the digesters
have indicated that the amounts of TRS produced from hardwood
cooks are greater than those produced from softwood cooks under
the same conditions (T, 8).  In the case of hardwoods, there is
an initial rapid rate of production of malodors that ultimately
approaches a constant rate that is about 10 percent greater
than softwoods.  As a result, a 4-hour hardwood cook will produce
about 30 percent greater quantity of odorous compounds than
a softwood cook  (7_, 8) .  The production of a greater quantity
of odorous compounds indicates that the syringyl methoxyls
from hardwoods react 10 percent faster than quaiacyl methoxyls
which are found in the softwoods  (T_, 8) .

Rate of Mercaptide Ion Attack on Lignin Methoxyl.  Two hypothe-
ses have been formed to account for the slow initial rate of
dimethyl sulfide formation.  The first is that as the pulping
proceeds the transfer of lignin into the soluble phase from
the solid phase would enhance the accessibility of the lignin
to mercaptide ion attack.  However, this hypothesis has been
partially disproved by showing that carbohydrate-free lignin
preparations, which would have better accessibility, still suffer
from slow initial attack by mercaptide ions (8).

The second hypothesis is accounted for by purely chemical
factors.  The structural changes which take place in the
lignin to cause solubilization during pulping, cause severe
degradation to lower weight fragments.  It may, therefore, be
expected that these changes would effect the methoxyl reactivity (8)

Temperature Dependance of Reactions.  Experimental laboratory
investigation has derived the activation energies for the principle
reactions occuring during pulping (7_) .  The activation energies
for the odor forming reactions (Eq. 4.14 and 4.16) are 7.6 and
11.3 kcal/mole, while the activation energy of the delignification
has been estimated to be about 30 kcal/mole.

By inspection of the Arrhenius equation, which describes the
temperature dependence of the rate constant, it appears that
an increase in temperature will accelerate the delignification
reaction while having only a moderate effect upon the odor
forming reactions.

Thus, for example, if the cooking temperature were raised
from 160 to 190C the rate of delignification would be increased
by a factor of 10 while the odor forming reaction rate would
be increased by a factor of about 2.3.  Thus for the same
amount of delignification the odorous compounds formed during
the 190C cook would be only one-fourth of the amount produced
at 160C.
                              4-27

-------
 It is worth noting that at elevated temperatures  the  formation  of
 odorous gases (see Eqs. 4.14 and 4.16)  takes  place  at a greater
 rate.  The practice of blowing a digester at  the  earliest time
 which is consistant with the pulp quality desired is  practiced  for
 economic reasons.   However, 'the  importance  of practicing this
 proceedure from an emissions standpoint can be seen in the previous
 example.

 A continuous digester can eliminate these problems  because the
 temperature of the pulp can be raised and lowered quickly,  and
 the dissolved lignins can be removed before they  enter the
 activated forms which eventually cause  odors.

 The Effect of Sulfidity.  Because of the ionic equilibrium between
 sulfide ions and hydrosulfide ions, a higher  liquor sulfidity will
 result in higher hydrosulfide ion concentrations.   The net result
 will be a greater  formation of methyl mercaptan by  the reaction
 shown in Equation  4.14.

 The higher hydrosulfide ion concentrations will also  result in
 greater hydrogen sulfide emissions created by  steam stripping,
 although this problem appears  to be of  less importance than the
 additional methyl  mercaptan formation mentioned previously.  In
 general,  higher sulfidities will result in greater  losses  of
 reduced sulfur compounds.

 The Effect of pH.   The pH  of the cooking liquor has an effect upon
 the emission of  hydrogen sulfide and methyl mercaptan,  as  discussed
 in  Section 4.2.1.   Because methyl mercaptan is  readily evolved  at
 a pH below about 12,  it  is desirable to maintain a high residual pH
 after  the  cook to  minimize this  volatilization.  A high pH, however,
 will not prevent the  stripping of these gases  (7).  The feasibility
 of  controlling the pH in this instance  is  controversial.

 Heat Accumulator Size.   In cases  where  direct  contact  heat  accumulators
 are  used,  the  volume  of  water through which the digester blow gases
pass in the heat accumulator has  a great effect upon the emissions of
 two  of the reduced sulfur  gases.   Hydrogen  sulfide and methyl mercaptan
have limited solubilities  in water  (0.035 Ib/gal and 0.187  Ib/gal
respectively at  70F) , and the greater  the  volume of water  through
which the noncondensible gases pass,  the greater the absorption of
them will be.
                                 4-28

-------
4.2.4.3  Relative Importance of the Digester Relief and Blow
         Emissions

         The digester relief and blow may be the largest source
         of organosulfur emissions within the kraft mill.  This
         is because these compounds are primarily formed in the
         digesters and the first opportunity for stripping from
         the liquor is at this point.  At process points beyond
         this the residual organosulfur compounds will be stripped
         to a lesser extent.

         The digester is a relatively minor source of hydrogen
         sulfide emissions when compared with the recovery furnace,
         direct contact evaporators, multiple effect evaporators,
         and the lime kilns.  Sulfur dioxide emissions are almost
         negligible from the digester blow and relief.
4.2.4.4  Ranges of Emissions from the Digester Relief and Blow

         Taking into account the variability of the operating
         conditions, the ranges of emissions for gaseous sulfur
         compounds from batch digesters are listed in Table 4-9.
         Emission data from continuous digesters are not currently
         available and the emissions from such equipment must not
         be considered identical to batch digester emissions.
                          TABLE  4-9

            APPROXIMATE RANGES OF EMISSIONS FROM THE DIGESTER
                           RELIEF AND BLOW
                                              lb/ADT

            Sulfur Dioxide                  Trace - 0.01

            Hydrogen Sulfide                 0.01 - 0.12

            Methyl Mercaptan                 0.02 - 0.40

            Dimethyl Sulfide                 0.40 - 2.5

            Dimethyl Disulfide               0.20 - 1.50
                                 4-29

-------
  4.2.5  GASEOUS EMISSIONS FROM THE LIME KILN SYSTEM
4.2.5.1  Formation of Gaseous Pollutants

         There is little published information concerning  gaseous
         emissions from the lime kiln.   It has been considered to be
         a minor source of sulfur gases and thus  few studies have been
         made.

         Possible sources of sulfur compounds  into the kiln system
         include the fuel used to fire  the unit,  residual  concen-
         trations of reduced sulfur compounds  in  the lime  mud, non-
         condensible gases burned in the kiln, and scrubbing liquor
         used in the kiln scrubbers.

         Taylor theorizes (19)  that a part of  the gaseous  reduced
         sulfur emissions from the kiln will depend upon the residual
         concentration of the reduced sulfur compounds and sodium
         sulfide concentration in the lime mud.   Thus the  thoroughness
         of washing the mud to remove these residual concentrations
         could greatly affect the emissions.  .Unfortunately no
         quantitative data exists on the residual concentration and
         emission relationship.   The mechanisms by which reduced sulfur
         compounds may be produced and  their subsequent conversion
         are  unknown.

         Combustion of the noncondensible reduced sulfur compounds
         resulting from other processes in the lime kiln has been
         used with considerable  success.   In the  hot end of the kiln,
         these gases  as well as  those mentioned in the previous para-
         graph are subjected to  temperatures in the range  of 1500-1800F.
         Under these  conditions, with sufficient  excess oxygen, oxidation
         of the  reduced sulfur gases  takes  place  with a high degree of
         efficiency.   The critical  temperature and oxygen  ranges are
         unknown.

         Sulfur  dioxide which would be  a  gaseous  product of such
         oxidation reactions  as well  as of  the fuel oil combustion
        will  be subject  to  immediate chemical absorption  by the
         calcium carbonate or oxide.  The scrubbers used on all kiln
         systems  also  are  effective gas removal devices.   Very
         little  sulfur  dioxde is emitted  from  the kiln system for
         this  reason.
                                   4-30

-------
         Taylor (19)  has observed that where scrubbing liquor
         containing sulfides, such as weak wash,  filtrates  or
         evaporator condensates from unoxidized black liquor,
         is used in the lime kiln scrubbers  hydrogen sulfide,
         methyl mercaptan, dimethyl sulfide and dimethyl disulfide
         may be stripped.  He noted that evaporator condensates
         from well-oxidized weak black liquor do  not result in
         any significant increase in odor level.
4.2.5.2  Effect of Operating Variables upon Emissions

         Data on this are not available.


4.2.5.3  Relative Importance of Lime Kiln System Emissions

         Data not available

4.2.5.4  Ranges of Emissions from the Lime Kiln System

         Warther and Amberg (27)  have reported a range of
         0.01 - 0.83 Ib/ADT of total reduced sulfur emissions
         from the lime kilns of four different pulp mills.

         More complete data are not now available although work
         is currently under way to determine such information.

                    ~ ->

4.2.5.5  Emissions Under Optimum Conditions

         Data not available.
                                 4-31

-------
  4.2.6  GASEOUS  EMISSIONS  FROM THE MULTIPLE EFFECT EVAPORATOR
4.2.6.1  Formation of Gaseous  Pollutants

         Concentration of black  liquor  from 13 - 16 percent solids
         to 48 -  55 percent  is almost always carried out with a
         multiple effect evaporation system.  A multiple effect
         evaporator arrangement  serves  as  an economical means for
         accomplishing this  because in  general one pound of steam
         will evaporate four to  five pounds of water.  Usually,
         five or  six evaporation units  (effects) make up the system.
         Each effect consists  of a vapor head and a heating element.
         Hot vapors from the vapor head of a previous effect pass
         to the heating element  of the  following effect.  The
         effects  are operated  at successively'lower pressures
         which causes a decrease in the boiling point of the liquor.
         Vapors after'the final  effect  are condensed'in a condenser
         rapidly  enough to maintain a high vacuum.  A typical
         multiple effect evaporator is  shown in Figure 4-6.

         The emissions  from  the  multiple effect evaporators are
         noncondensible reduced  sulfur  gases which are vaporized
         or stripped during  the  boiling.   These noncondensible
         gases, with vapors  created during boiling, pass to the
         heating  element of  the  following  effect.  In order to
         eliminate an accumulation of noncondensible gases in the
         heating  element each  heating element is provided with a
         gas vent.   The vents  from the  heating elements that are
         under a  pressure greater than  atmospheric are vented to
         its vapor head.  The  vents from the heating elements
         under a  vacuum are  usually valved to a common header
         going directly to either a barometric or surface condenser.

         With a barometric condenser in use a limited quantity of
         hydrogen sulfide and  methyl mercaptan gases are soluable
         in  the water spray.   The condensate will then become a
         potential water pollution problem.  A small steam jet is
         used to  remove noncondensible  gases.  If a surface condenser
         is  used  the  noncondensible gases  are separated from the
         condensibles.  A small  steam jet  is used to remove the
         noncondensible gases..   It is these noncondensible gases that
         create the problem  of air pollution from multiple effect
         evaporators.

        The reduced pressure  in the latter effects will result in
         a higher evolution  of the reduced sulfur compounds.  This
        increased evolution and the steam stripping of the reduced
                                  4-32

-------
45 psi

        product



*



vapor
f 	
Vapor Hd.
250 F
16 psig
Heating
Element



s
1


-
1
i
*
i
                   I
                   i
                   condensate















non-c
water, i
Cond.
{ 	 1 f 	 1 
-------
         sulfur compounds are responsible for the emissions from
         the multiple effect evaporators.  The steam stripping
         will be enhanced by the creation of foam within the
         evaporator tubes, because the foam will present a greater
         interfacial surface area for stripping.
4.2.6.2  Effect of Operating Variables Upon Emissions

         Because emissions from the evaporators are caused by
         the steam stripping of reduced sulfur compounds and
         by the direct volatilization of these compounds, the
         sulfidity and the pH of the liquor will tend to be
         controlling factors in the quantity of gases emitted.
         The effects of these variables have been discussed in
         Section 4.2.1 and 4.2.3.

         If weak black liquor oxidation has been performed, the
         emissions will be reduced because of the removal of
         the reduced sulfur compounds.

         An important factor entering into the quantity of
         emissions from the evaporators when unoxidized black
         liquor is being processed, appears to be the type of
         condenser utilized.  Harding (20)  presented data on
         the emissions using two different types of condensers.
         These data are presented in Table 4-10.

         Barometric condensers provide a reduction in the emission
         of reduced sulfur gases, but provide a contaminated conden-
         sate which may pose a water pollution problem.  These
         reduced sulfur gases which have been scrubbed may be
         stripped from the condensates if the condensates are later
         used in the process.

         Surface condensers provide a more efficient means for
         the collection and later destruction of the noncondensible
         gases.
                               4-34

-------
                         TABLE  4-10

          GASEOUS EMISSIONS FROM MULTIPLE EFFECT EVAPORATORS  (20)


                               (lb/ADT)

   Condenser Type	H S	RSH	RSR	RSSR

Surface                           4.80     1.44      0.35       0.62

Barometric (with loss at
 noncondensible jet)              0.04     0.03      0.04       0

Barometric (losses from
 hot well)                        0.13     0.20      0.14       0.02



4.2.6.3  Relative Importance of the Multiple Effect Evaporator

         Noncondensible emissions from multiple effect evaporators
         are low volume/ highly concentrated streams, and represent
         a major emission source within a kraft mill.  Although
         black liquor oxidation may reduce the emissions significantly,
         the concentrations of reduced sulfur gases is such that
         further processing of the noncondensible gases is required.
         Overloading the evaporators should not increase the emissions
         from the evaporator per evaporated pound of solids introduced.


4.2.6.4  Ranges of Emissions from the Multiple Effect Evaporators


                        TABLE  4-11

               APPROXIMATE RANGES OF EMISSION FROM THE
                      MULTIPLE EFFECT EVAPORATORS
                     Oxidized Black Liquor    Unoxidized Black Liquor
                             (lb/ADT)                  (lb/ADT)

Sulfur Dioxide            0.01                     0-0.01
Hydrogen Sulfide          0.01-0.02              0.10-3.0
Methyl Mercaptan          0.10-0.30              0.10-1.50
Dimethyl Sulfide          0.05-0.15              0.05-0.08
Dimethyl Disulfide        0.05-0.15              0.01-0.02
                                   4-35

-------
4.2.6.5  Emissions Under Optimum Conditions

         Because of the wide variation in the design of multiple
         effect evaporators (i.e.,  the number of effects,  type
         of evaporator use, feed locations, steam characteristics,
         and the variety of condensers utilized)  the variability
         of conditions makes it impossible to define an optimum
         set of conditions for which to predict emissions.
                               4-36

-------
  4.2.7  GASEOUS EMISSIONS FROM THE BLACK LIQUOR OXIDATIOft TOWER
4.2.7.1  Formation of Gaseous Pollutants

         Black liquor oxidation accomplishes the goal of converting
         the volatile reduced sulfur compounds  of the black liquor
         to non-volatile or less volatile states.  Thus the sulfide
         ions of the liquor are converted to thiosulfate ions,  and
         the organosulfur compound are oxidized to dimethyl disulfide.
         Oxidation units come in a wide variety of styles,  some of
         the more common styles are thin film towers, packed towers,
         and bubble trays.  All oxidation units attempt to  provide
         intimate contact between liquor and air while providing
         ease of handling black liquor.

         Gaseous emissions from the oxidation tower are created by
         the stripping of the reduced sulfur compounds from the
         liquor by the air passing through it.   Comparatively large
         volumes of dimethyl disulfide are emitted from this source,
         which may be explained by three factors.  The first is the
         residual concentration of dimethyl disulfide in the liquor,
         the second is the fact that the methyl mercaptan and dimethyl
         sulfide are oxidized to dimethyl disulfide in the liquor,
         and the third is that methyl mercaptan and dimethyl sulfide
         which have been stripped into the gas may be oxidized in the
         gaseous states to dimethyl disulfide.  Because dimethyl
         disulfide is the least volatile form of the organosulfur
         compounds present in the liquor, it would be preferable to
         accomplish the oxidation of the organosulfurs to dimethyl
         disulfide as quickly as possible to retain as much of the
         sulfur in the oxidation tower as possible.


4.2.7.2  Effect of Operating Variables Upon Emissions

         The changes in operating variables which may  favorably effect
         emissions from the oxidation tower may  also have  a detrimental
         effect upon the  efficiency of the black liquor oxidation.
         However, there has not been enough work done  in this  area
         to discuss these effects thoroughly.  It has  been established
         that the temperature of the liquor must be held above about
         160F in order to prevent  formation of  elemental  sulfur.
         Higher temperatures  could  result in a more  efficient  oxidation
         operation  (power requirements,  as well  as overall efficiency),
         however, a higher temperature would mean greater  volatility
                                    4-37

-------
         of the reduced sulfur compounds/ and hence greater
         emissions.  Another variable would be the air flow rate
         through (or over) the liquor.  (From a given flow rate of
         air the effect of increasing the flow rate of air upon
         the oxidation efficiency and the emissions is not established.)

         Black liquor oxidation is designed to decrease the emissions
         from the direct contact evaporator.  For this reason the
         effects of the variables mentioned above upon the emissions
         from the oxidation tower must be balanced against the effect
         that a greater oxidation efficiency might have upon the
         emissions from sources effected by liquor oxidation.  In
         other words, a slight increase in emissions from the oxidation
         tower created by conditions necessary for more efficient
         oxidation might result in a decrease in emissions throughout
         the mill of significantly greater magnitude.  However, this
         balance must be studied in much greater detail on individual
         plants before any quantitative relationship can be developed.

         In oxidation towers where oxidation is not completed to a
         high percentage (99+ percent), the residual reduced sulfur
         gases may be stripped from the liquor by the gases being
         passed through it.  In a two stage oxidation system, the
         first stage would involve such a case.
4.2.7.3  Relative Importance of the Oxidation Tower

         The organosulfur emissions from the oxidation tower, particu-
         larily the dimethyl disulfide emissions rank as the third
         largest source of emissions of this type behind the digester
         relief and blow, and the multiple effect evaporators.  The
         emission of hydrogen sulfide and sulfur dioxide emissions
         from this source is negligible and the oxidation tower as
         a unit is considered a small source of atmospheric emissions.
                                  4-38

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4.2.7.4  Ranges of Emissions from the Oxidation Towers






                         TABLE  4-12




         APPROXIMATE RANGES OF EMISSION FROM OXIDATION  TOWERS






                                            (lb/ADT)




Sulfur Dioxide                          0.00 - 0.01




Hydrogen Sulfide                        0.01 - 0.02




Methyl Mercaptan                        0.05 - 0.10




Dimethyl Sulfide                        0.02 - 0.08




Dimethyl Disulfide                      0.05 - 0.15






4.2.7.5  Emissions Under Optimum Conditions




         This information is not available at the present time.
                                4-39

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  4.2.8  GASEOUS EMISSIONS FROM THE STOCK WASHERS
4.2.8.1  Formation of Gaseous Pollutants

         Emissions from the brown stock washers arise primarily
         from the vaporization of the volatile reduced sulfur
         compounds.  There are no chemical reactions which take
         place.  However, there is a shift in the equilibrium for
         hydrogen sulfide and methyl mercaptan.  Since the washer
         water has approximately a neutral pH, the dilution of the
         liquor by the water will cause a lowering of the pH to
         approximately 10.0.  This pH is below the equilibrium
         point for methyl mercaptide ion and results in a correspond-
         ing shift to methyl mercaptan gas  The lower pH will
         also cause an increase in the concentration of dissolved
         hydrogen sulfide.  However the equilibrium point of H S
         ( 8.0) will not be reached.

         It is therefore reasonable to expect a large proportion
         of the emissions from the washers to be methyl mercaptan.

4.2.8.2  Effect of Operating Variables Upon Emissions

     :    There are no well defined relationships for the effect
         of operating variables upon ..emissions from the washers,
         but several operations can be discussed quantitatively.

         The amount of air drawn over the stock washers will affect
         the emissions because greater air flows will present greater
         driving forces for the mass transfer of the dissolved gases
         into the surrounding atmosphere.

         The temperature of the water is also important because the
         volatility of the hydrogen sulfide and methyl mercaptans
         increases with temperature.  The pH of the water also affects
         the emissions as previously discussed.  The turbulence of the
         mixing of pulp and washer water may cause increased interface
         between the atmosphere and the liquid resulting in additional
         volatilization.

         The thoroughness with which the liquor is removed in the first
         stage washer is important.  If the liquor is efficiently removed
         in the first stage, the pH of the resulting weak liquor may
         remain sufficiently high to limit hydrogen sulfide emissions.
         There would also be less liquor in the remaining stages.
                                 4-40

-------
4.2.8.3  Relative Importance of the Emissions  from the Stock Washers
         The emissions from the stock washers are extremely low in
         all cases with the possible exception of methyl mercaptan.
4.2.8.4  Ranges of Emissions from the Stock Washers


                         TABLE  4-12

      APPROXIMATE RANGES OF EMISSIONS FROM THE BROWN STOCK WASHERS


                                              lb/ADT

Sulfur Dioxide                          0.01 - 0.02

Hydrogen Sulfide                        0.01 - 0.12

Methyl Mercaptan                        0.10-0.25

Dimethyl  Sulfide                       0.01 - 0.02

Dimethyl Disulfide                      0.01-0.02


4.2.8.5  Emissions Under Optimum Conditions

         The data are not available at present.
                                4-41

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   4.2.9   GASEOUS  EMISSIONS  FROM THE  SMELT DISSOLVING TANK
 4.2.9.1  Formation of Gaseous Pollutants

          The  gaseous emissions from the smelt dissolving tank
          are  reduced sulfur compounds.  Because the organosulfur
          compounds could not exist in the smelt at the smelt
          temperature, their presence in the vent gases must be
          accounted for by  the introduction from outside sources.
          One  such source might be the drafting of gases from the
          reducing zone of  the furnace through the smelt spout of
          the  furnace into  the smelt tank.  The natural draft of
          the  smelt tank might cause a sufficient draft upon the
          furnace gases to  pull these through a partially filled
          spout.  Another source of organosulfur compounds might
          be the water used for smelt dissolving.  In some instances,
          condensate water  bearing these compounds is introduced
          to the causticizing system by way of the lime kiln
          scrubber and subsequently reach the smelt tank.  A study
          of the water cycle from the scrubber will show that a
          portion of these  condensates may eventually enter the
          smelt tank (see Kraft Flow Diagrams, Chapter Three) where
          the  temperature would be favorable for volatization.
          However, the effect of such condensates in the smelt
          tank is believed  to be very small.

          Of course the chemical equilibrium of sulfide ion created
          by the dissociation of sodium sulfide, will create a
          condition for hydrogen sulfide emission resulting from
          stripping.
4.2.9.2  Effect of Operating Variables upon  Emissions

         Because the smelt tank is essentially an uncontrolled
         reaction vessel, there are no operating variables which
         can effect the emissions.  However, proper design of the
         smelt spout could alleviate some of the emissions resulting
         from gases drawn from the recovery furnace.
4.2.9.3  Relative Importance of the Smelt Tank
         The smelt tank is a minor source of emission of all gaseous
         compounds emitted from the kraft recovery system.
                            4-42

-------
4.2.9.4  Ranges of Emissions from the Smelt Tank






                         TABLE  4-14




          APPROXIMATE RANGES OF EMISSIONS FROM THE SMELT TANK






                                              (lb/ADT)




Sulfur Dioxide                               0




Hydrogen Sulfide                             0.02 - 0.05




Methyl Mercaptan                             0.02 - 0.05




Dimethyl Sulfide                             0.01 - 0.02




Dimethyl Disulfide                           0.0  - 0.01






4.2.9.5  Emissions Under Optimum Conditions




         The data are not currently available.
                               4-43

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     4.3   PARTICULATE  EMISSIONS FROM THE KRAFT PROCESS
   4.3.1   PARTICULATE EMISSIONS FROM THE KRAFT PROCESS - GENERAL

          Particulate emissions from the kraft process occur primarily
          from the recovery furnace, the lime kiln, and the smelt
          dissolving tank.  They are caused mainly by the carry-
          over of solids plus the sublimation and condensation of
          inorganic chemicals.  The sublimation and condensation
          normally produces a fume.  Little information is avaialble
          on the actual range of particle sizes from these sources,
          especially in the recovery furnace when agglomeration tends
          to occur readily.  In addition, particulate emissions occur
          from combination and power boilers.
  4.3.2  PARTICULATE EMISSIONS FROM THE RECOVERY FURNACE AND DIRECT
         CONTACT EVAPORATORS
4.3.2.1  Particulate Formation

         Particulate emissions from the recovery furnace and direct
         contact evaporator complex consist primarily of sodium sulfate,
         and sodium carbonate.  These emissions may result from both
         of the processes previously described.  The high flue gas
         velocity may cause the carry-up of small droplets of black liquor
         which have been sprayed into the furnace.  These droplets should
         burn in the oxidizing zone, but some of them may escape from
         the furnace.

         The inorganic sodium salts which are found in particulate
         emissions from the furnace may be carried up by the furnace
         draft or may be formed in a vaporization - condensation
         process.

         There are no particulates contributed by the direct contact
         evaporator.  In fact, the evaporator may serve as a particu-
         late reduction device, the method of reduction depending upon
         the type of evaporator in use.
4.3.2.2  Effect of Operating Variables Upon Emission

         The portion of the sodium salt particles created by
         the sublimation-condensation process is not controllable
         because the initiating step, sublimation, takes place on
         the smelt pile where control is virtually impossible.
                                 4-44

-------
The portion of the particulate emissions which are
attributable to the carry-up of black liquor solids is
controllable to a small extent.  The amount of solids
carried up by the induced draft is dependent upon the
spray droplet size and the vertical velocity in the
furnace  (see Section 4.2.2.2).  Thus a large spray
"droplet size will reduce the carry-up of solids within
the furnace.                                '

Once in the oxidizing zone of the furnace, the solids
will burn to gaseous and solid." products.  The solid
products will initially consist of sodium sulfate,
sodium carbonate, and organic solids.  The sodium
carbonate may react with the flue gas sulfur dioxide
and oxygen to form additional sodium sulfate.  The
extent of this conversion will depend upon the sulfur
dioxide concentration in the gas.

The organic solids will undergo a combustion-oxidation
reaction.  In most instances the oxidation will not be
100 percent efficient and some carbon residue will escape
from the furnace.  The operating conditions of temperature,
percent excess oxygen, turbulence, and residence time will
affect the efficiency of this reaction.

As mentioned in the previous section, the particulate
concentration may be reduced when the flue gas passes
through  the direct contact evaporator.   In a cascade
evaporator a high flue gas velocity will provide a greater
impingement rate for the particulates than a lower velocity.
A Venturi evaporator can actually serve  as a particulate
scrubber.

Particulate emissions from the recovery  furnace-direct
contact  evaporator complex are dealt with more effectively
with particulate control devices such as electrostatic
precipitators and Venturi scrubbers.  It would be more
advantageous to control furnace  operating conditions  to
minimize gaseous emissions rather than particulate emissions,
Although most conditions resulting in reduced gaseous
emissions also serve to reduce particulate emissions.
                        4-45

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4.3.2.3  Relative Importance

         The kraft recovery furnace is the largest source of
         particulate emissions in the pulping system.  Particulate
         control devices currently in use remove 80 - 99 percent
         plus of the particulates from the flue gas.
4.3.2.4  Ranges of Emissions

         The range of particulate emissions from the recovery furance
         and direct contact evaporator (cascade and cyclone)  is 75 -
         125 Ib/ADT without control devices.  Using a 90 percent
         venturi evaporator scrubber after the furnace, the particulate
         emissions are in the range of 2- - 40 Ib/ADT.
4.3.2.5  Emissions Under Optimum Conditions

         These data are not currently available.


  4.3.3  PARTICULATE EMISSIONS FROM,THE LIMg KILN


4.3.3.1  Particulate Formation

         Particulate emissions from the lime kiln consist of the
         sodium salts, calcium carbonate, calcium sulfate, calcium
         oxide, and insoluble ash.  The presence of the sodium salts
         may be accounted for by the  sublimation-condensation process
         described in Section 4.3.2.1 and by dust entrainment within
         the kiln.  However,  neither  calcium carbonate, nor calcium
         oxide will vaporize  at temperatures within the kiln and
         the presence of calcium carbonate and calcium sulfate must
         be explained by the  entrainment of the calcium carbonate
         and calcium oxide.   The particles of calcium oxide may
         react with either the carbon dioxide or sulfur dioxide within
         the kiln to yield the appropriate calcium salt.  Calcium
         carbonate may react  with the sulfur dioxide and then oxygen
         to yield calcium sulfate.
                                4-46

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             CaO  +  C02    CaC03                      Eq.  4.19

             CaO  +  SO     CaSO                       Eq.  4.20
                               *J

           CaCO3  +  S02    CaS03  +  CO               Eq.  4.21

           CaS03  +  1/20   CaS04                      Eq.  4.22
         The presence of the ash may stem from the burning of the
         fuel oil in the kiln.
4.3.3.2  Effect of Operating Variables upon Emissions

         Other than controlling the rate of material output there
         appears to be no way of controlling the particulate emission
         for the lime kiln through manipulation of operating
         variables.
4.3.3.3  Relative Importance of Lime Kiln Particulate Emissions

         The particulate emissions from the lime kiln (before the
         control equipment) are about one-fourth, the emissions from
         recovery furnace but are still significantly large.  However,
         the relatively low gas flow rates through the lime kiln
         allow installation of moderately priced high efficiency
         wet scrubbers which can reduce particulate emissions to
         low levels.  At the present time, most lime kilns are
         equipped with wet scrubbers whose efficiencies range from
         80 - 99 percent on the calcium salts.  The particulate
         emissions from the lime kilns whose scrubber efficiencies
         are in the lower part of the range may be significant.
4.3.3.4  Ranges of Emission from the Lime Kiln

         The range of particulate emission from the lime kiln
         before the particulate control equipmentis 20 - 65
         Ibs/ADT.
4.3.3.5  Emission Under Optimum Conditions

         These data are not currently available.
                                  4-47

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4.3.4  PARTICULATE EMISSIONS FROM THE SMELT DISSOLVING TANK AND
       SLAKE TANK

       The range of particulate emissions from the smelt dissolving
       tank and slake tank are of a low magnitude (1.0 - 4.0 Ib/ADT
       and 4.0 - 6.0 Ib/ADT respectively).  The emissions are primarily
       caused by the entrainment of large particles in the vent gases.
       Because of the violent reactions taking place in each of these
       tanks, it is reasonable to expect that the turbulence of the
       dissolving water will splash water droplets containing both
       dissolved and undissolved inorganic salts above the surface.
       Here, because of the high temperature of the vent gases, the
       water may evaporate leaving the solid particles in suspension
       above the liquid.  These particles may be carried out by the
       vent gases if they are not of sufficient weight to drop back
       into the liquid.
                               4-48

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4o4  NSSC PROCESS - GENERAL

     "As in the acid suliite process, neutral sulfite pulping
     depends on sulphonatio.i and hydrolysis of tne lignin to
     softer, the rigid matrix in which the wood fibers are
     bound together.  Since suiphonation takes place slowly
     and to a land.red extent, involving "A" groups cf lignin
     only, high temperatures in the range of 160 to ISO'C
     are required to complete the reaction, within a reasonable
     time.  Although the dissolution of the lignin is described
     as a two-stage process-sulphonation followed by hydrolysis-
     soiubilization begins quite soon, since some of the lignin
     molecules- are small enough to dissolve immediately on
     suiphonation, in contrast to the ^arge molecules which
     must hydrolyze before they can pass into solution"(21) .

     "In semichemical pulping perhaps one-half or less of the
     total lignin is removed.  In preparing bleachable pulps,
     it is not economical to cook much below a lignin content
     of 10 percent in the pulp because cooking time, carbohydrate
     loss, and chemical requirement increase disproportionately.
     Although the neutral character of the liquor is a handicap
     in suiphonation, it is beneficial insofar as it reduces
     loss of carbohydrate by hydrolysis.  This contributes  to
     the exceptionally high yield and strength of NSSC pulps"(21).

     Because of the difference in the chemical attack on the lignin
     using sulfite liquors, such compounds as methyl mercaptan
     and dimethyl sulfide are not formed during digestion.  The
     NSSC process should therefore be free from these odorous
     compounds.  In addition, the absence of sulfide ions from
     the cooking liquor will virtually eliminate hydrogen sulfide
     as a possible emission,

     NSSC pulp mills handle  the spent cooking liquor in  a variety
     of manners.  Many NSSC  mills are located on the same property
     as kraft mills.  In these instances the spent  cooking  liquor
     can be mixed with the kraft black liquor and serve  as  make-
     up chemicals for the kraft processc  A process similar to  this
     is shown in the NSSC Flow Diagram No, 1  located in  Chapter 5.
     It is possible to recover some  of the chemicals from the
     smelt tank to provide fresh cooking  liquor for the  NSSC
     pulping although this is not shown -
                                 4-'i9

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Another method of handling the spent cooking liquor is to
simply discharge the liquor to settling ponds/ soil filtration
or  aeration units without an attempt to recover the chemicals.
Such a system obviously will cause stream pollution.  In
the system shown in NSSC Flow Diagram No. 2, a percentage
of  the spent liquor is mixed with the fresh cooking liquor
while the remaining spent liquor is discharged to the sewer.

For NSSC mills which do not have kraft recovery systems
available, the chemicals of the spent liquor may be
recovered in a fluidized bed reactor in the form of sodium
sulfate and sodium carbonate.  A fluidized bed recovery
system is shown in NSSC Flow Diagram No. 3.

In  each of the spent liquor handling systems mentioned above
cooking liquor must be prepared from fresh chemicals.  There
are two methods available for the preparation of fresh liquor.

One is to mix soda ash and sodium sulfite together with the
proper amount of water.  Spent cooking liquor may be used
to provide some of the chemicals and water.

Another method is to burn raw sulfur to sulfur dioxide in
a sulfur burner and subsequently absorb the SO  in an absorp-
tion tower using a soda ash solution for an aqueous medium.

Atmospheric emission sources from an NSSC mill are limited
to SO. absorption towers, blow pits, spent liquor evaporators,
and fluidized bed reactors.  In the case of spent liquor
recovery in a kraft mill recovery system, the NSSC liquor
will have an effect upon the emissions from the kraft recovery
system.  Each of these sources will be discussed in the
following sections.

The quantities of atmospheric emissions from the NSSC emissions
sources are unknown at the present time and subsequent discussions
deal with qualitative aspects of emissions from the NSSC systems
only.
                              4-50

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  4.4.1  GASEOUS EMISSIONS FROM THE NSSC PROCESSES
4.4.1.1  Sulfur Dioxide Absorption Tower

         Sulfur dioxide absorption towers generally are counter-
         current packed towers using sodium carbonate (soda ash)
         as the absorbing medium.  The chemical absorption takes
         place according to the following reaction:


              2 Na   +  C03 = +SO2 - 2 Na+  +  S0~ + CO f    Eq.  4.23


         This reaction will lead to the emission of carbon dioxide.
         Sulfur dioxide may also be absorbed in water according
         to the following reaction:


              HOH  +  SO2 -> 2 H+  +  SO~                     Eq.  4.24


         Nearly total absorption of sulfur dioxide in the tower is
         feasible in a properly designed and operated tower.  The
         quantity of sulfur dioxide emitted from the tower will
         depend upon the efficiency of operation.  Quantitative data
         of the emission of sulfur dioxide is therefore dependent
         upon the design and operating conditions of the individual
         towers.
4.4.1.2  Blow Pit

         When the cooked pulp is blown into the blow pit, large
         amounts of steam and gases escape from the pulp and spent
         liquor.  Sulfur dioxide seems to be the major gaseous
         emission from the blow pits .  Recently, recovery systems
         have been installed to recover-  the  sulfur dioxide from
         the blow pit gases .  Installations in NSSC mills have been
         of individualistic design but all installations are based
         upon the absorption of sulfur dioxide by wet scrubbing
         either in the vent stack or by routing the gas through
         an SO  absorption tower.  Again the efficiency of operation
         will dictate the quantity of sulfur dioxide emissions from
         the blow pit.

4.4.1.3  Fluidized Bed Reactor

         Fluidized bed reactors have been developed for NSSC mills
         which do not have kraft mill recovery  facilities for
         disposing of their spent liquors.  Fluidized beds can
                                    4-51

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          accomplish the complete oxidation of organic wood constituents
          in  the liquor yielding gaseous products of carbon dioxide, water,
          and minute traces of other organic compounds.  Recovery of
          the cooking chemicals is in the form of sodium sulfate and sodium
          carbonate.  These chemicals may be reused as kraft mill make-up
          chemicals.  The ratio of sodium sulfate to sodium carbonate
          products may be controlled by the operating conditions in the
          fluidized bed.

          In  principle the spent cooking liquor is concentrated to
          approximately 30-40 percent solids and is sprayed into the
          top of the bed.  As the liquor falls and comes into contact
          with the rising gases evaporation occurs.  The temperature
          of  the gases above the bed is approximately 800-1000F.
          The partially dried liquor will either fall onto the bed
          or  deposit on rising entrained dust particles and become
          thoroughly dried.  As these particles grow they become too
          heavy to become entrained and will stay on the bed.  Entrained
          particles which escape the reactor are collected in suitable
          mechanical dust collectors and are returned to the bed.

          At  the temperatures found above the bed, essentially none of
          the organic chemicals will undergo oxidation.  The temperature
          of  air supplied to the bed is approximately 1100-1200F, while
          the bed temperature is in the range of 1200-1400F, slightly
          higher than the air supplied because of the exothermic
          reactions taking place.

         Under normal operating conditions atmospheric emissions
          from a fluidized bed reactor with dry and wet mechanical
          control devices are low.  However, data on the actual
          emissions are not currently available.
4.4.1.4  Recovery in Kraft Systems

         Precise data are not available on the effect which mixing spent
         NSSC liquor with kraft black liquor has upon the emissions from
         kraft recovery units from the point at which they are mixed up
         to and including the recovery furnace.  However, the greatest
         effect that the mixing will have is to lower the pH of the
         kraft liquor.  Section 4.2 details the importance of maintaining
         a high residual pH of the kraft black liquor during the recovery
         process.  The effect of this mixing must be studied in greater
         detail.
                                       4-52

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  4.5  EMISSIONS FROM THE SULFITE PROCESS
4.5.1  EMISSIONS FROM THE SULFITE PROCESS - GENERAL

       There are four classes of sulfite pulping liquors:  acid
       sulfite, bisulfite, neutral sulfite, and alkaline sulfite.
       Table 4-15 gives the predominant cooking chemical and
       initial pH of each of the classes.  These two variables
       determine which class of sulfite pulping that a particular
       mill practices.

       Calcium, sodium, magnesium, and ammonia are the four base
       chemicals around which the sulfite processes have been
       designed.  At a pH below 6, it is proper to represent the
       sulfite in the cooking liquor as hydrosulfite ion (HSO ]_
       while above this pH it is represented as sulfite ion(SO_).
       The calcium and sulfite combination is insoluble in aqueous
       solution of pH above 2.  Hence, calcium sulfite cooking
       liquors are limited to the acid sulfite processes.  Magnesium
       sulfite is soluble in solutions whose pH is below 7  (approxi-
       mately) , and it may be used in acid sulfite, bisulfite, and
       over the lower end of the neutral sulfite range of pH.
       Ammonium sulfite is soluble in solutions of a pH below 9
       (approximately), while sodium sulfite is soluble over the
       entire range of pH.  The desired range of pH for the cooking
       liquor will dictate the type of cooking chemicals which can
       be used.

       As in the kraft pulping process, the objective of the sulfite
       cook is to dissolve the lignin in a wood chip and leave a
       fiber group which may be dispersed into an aqueous suspension
       suitable for paper making.  The method of attack by  sulfite
       liquors  on lignin is different than the kraft liquor chemical
       attack.  The sulfite and neutral  sulfite processes involve
       lignin  sulphonation, acid hydrolysis, and acid condensation  (22)
       In sulfite cooking, the products  of lignin-sulfite reactions
       do not  produce volatile reduced sulfur compounds such as
       methyl  mercaptan and dimethyl sulfide.

       Sulfur  dioxide is the principle atmospheric  emission from
       the sulfite processes.  The main  causes of SO  release are
       stripping by gas streams  and volatilization  during periods
       of high liquor temperature.  Hydrogen sulfide emissions  are
       possible during recovery  of the spent liquors if the recovery
       system  is not maintained  under proper oxidizing  situations.
                                    4-53

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                                  TABLE  4-15

                             PREDOMINATE CHEMICALS AND pH
                             OF SULFITE COOKING LIQUORS (23)

                                                                Approximate
                                    Predominate Chemical        initial pH
              Name                    in Cooking Liquor         at 25C	

         Acid sulfite               H->so + XHSO                  1-2
                                     ^  J       .J

         Bisulfite                  XHSO                          2-6

         Neutral sulfite            XSO  + XCO                    6-9+
                                       3      j

         Alkaline sulfite           XSO  + XOH                        10+


  4.5.2  GASEOUS EMISSIONS FROM SULFITE PROCESSES
4.5.2.1  Gaseous Emissions from Absorption Towers

         Industrial absorption towers for sulfite processes are usually
         packed towers or Venturi absorbers.   In the case of packed towers,
         sulfur dioxide gas is introduced in  the bottom of the tower
         while a corbonate solution of the desired base (sodium, etc.)  is
         introduced at the top of the tower.   In the case of calcium, lime-
         rock (CaCO )  is introduced as packing into the tower.  Sulfur
         dioxide reacts with water to yield an acidic solution.
                                    	    v
                                      acidic  '
              2H+  +  SO~  -> H+  +  HSO~  -*  H SO   ->  HO + SO        Eq. 4.25
                        j  X^           J  *    ^  J  ^"   t      f+
                                  ,   basic
                                  v	
         Carbonate in  solution will undergo an adjustment in equilibrium
         as the hydrogen ion concentration increases.  The result is the
         production of carbon dioxide gas.


              CO~  +  H+  J  CO   \ + HO                              Eq. 4.26


         This  reaction depletes the concentration of hydrogen ion
         and tends to  maintain a constant pH.

         Acid fortification towers are absorption towers.  Weak cooking
         liquor is passed through the tower for the purpose of absorbing
         additional sulfur dioxide.   This replenishment of sulfite in the
         liquor offsets the sulfite lost through mill emissions as sulfur
         dioxide or combined in lignosulphonic  acids in the pulping process.

                                         4-54

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         Sufficient data are not available to adequately determine
         a range of sulfur dioxide emissions for gas absorption
         towers.  The quantity of sulfur dioxide gas delivered
         to the absorption tower will depend upon the desired
         pH and strength of-inorganic chemicals in the cooking
         liquor.  Currently  available data show that the sulfur
         dioxide emissions from the absorption tower are in the
         range of 15-20 Ib/ADT before secondary scrubbing of
         the overhead gases.
4.5.2.2  Gaseous Emissions from Digester Relief and Blow Gases

         Gaseous sulfur dioxide emissions from digester relief
         and blow gases stem from the temperature increase of
         the cooking liquor.  Gases in general become less soluble
         in aqueous solutions during temperature rises.  Sulfur
         dioxide is such a gas.  Temperatures in the digester
         may range from 120C to 180C.  When relief lines are
         opened and the pressure within the digester is relieved
         large quantities of sulfur dioxide will be emitted with
         the escaping steam.

         There are three methods of discharging the-digester; hot
         blowing, cold blowing, and flushing.  In a hot blow, the
         pressure in the digester is relieved to a predetermined
         level and the contents are then blown into a blow pit.

         In cold blowing, the pressure in the digester is relieved
         to a low level and the contents are then pumped into a
         dump tank below the digester.  Spent liquor is introduced
         into the bottom cone of the digester to reduce pulp
         consistency and aid discharge.

         In the flushing system, after the digester has been relieved,
         spent liquor or hot water is pumped into the digester for
         several minutes at a high rate.  The blow valve is then
         opened and the pulp is discharged while the flushing liquid
         continues to enter the digester.

         The three types of digester discharge affect the amount
         of sulfur dioxide which is emitted to the atmosphere.
         Gases which leave the digester during relief are sent
                                    4-55

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         to the accumulators where they fortify the cooking liquor.
         The gases which pass through the accumulators are sent
         to other areas in the process where they may be absorbed.
         However, blow tanks and dump tanks are usually vented
         to the atmosphere.  Gases carried from the digester to
         these tanks may therefore be sources of emissions.  Recent
         installation of gaseous control devices on blow pit gases
         will reduce these emissions.

         A review of the digester discharge systems shows that for
         the hot blow style the pressure is only partially relieved
         before the blow is made.  The digester gases which were not
         relieved will be sent to the blow pit during the blow.
         Significant quantities of sulfur dioxide are therefore
         emitted in this style of discharging if no recovery is
         practiced.

         In the cold blow and flushing style of discharging the digester,
         the pressure is almost fully relieved, and the relief gases
         are routed to the accumulators.  That fraction of the gases
         which remains in the digester may then escape from the system
         when the pulp is discharged to the dump tanks.  Table 4-16
         shows what ranges of sulfur dioxide emissions might be
         expected from the blow pit vent stack.
                                TABLE  4-16

                 APPROXIMATE EMISSIONS FROM BLOW PIT OR DUMP TANK VENTS
                                (WITHOUT SCRUBBING)
                    Blow Pit                         100 - 150 Ib/ADT

                    Dump Tank                         10-25 Ib/ADT
4.5.2.3  Gaseous Emissions During The Recovery of Spent Cooking
         Liquors

         Practices in the recovery of the base used in pulping
         differs widely from mill to mill, as researchers find
         more effective methods of chemical reclamation.  Because
         of the variety of chemical and physical properties
         exhibited by the base chemicals, calcium, sodium,
         magnesium, and ammonia, different processes have been
         developed to satisfy the handling and recovery problems
         peculiar to each base.  In some instances no attempt
         is made to recover the chemical or sensible heat of the
         spent liquors, or in some cases only the heat is recovered.
                                       4-56

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The four sulfite processes presented in the flow
diagrams located in Chapter 3 represent the four
most widely used processes and the attendant recovery
systems.  They will be the recovery processes which
will be discussed primarily in this section.

"In the case of calcium base liquors the scaling of
evaporator surfaces, the need for all stainless-
steel equipment, the relatively low value and the
chemical complexity of the resultant smelt, and
the difficulty with fly ash" (24) have led to
the common practice of simply disposing of the spent
liquors by a convenient means and making no attempt
to recover the heat or chemicals.  Sulfite mills
which incorporate these processes usually utilize
sulfur dioxide absorption towers in conjunction with
a sulfur burner as shown in Sulfite Plow Diagram
No. 2.  The digester relief gases also may be routed
through the accumulator tanks for recovery of sulfur
dioxide.  Gases vented to the accumulators are further
routed through the acid-making system to recover as
much SO  as possible.  Spent liquors which are disposed
of by means of a sewer may present severe water
pollution hazards.

Spent "liquor from several magnesium sulfite processes
can be burned in a simple heat- "arid chemical-recovery
system in which the inorganic salts break down into
magnesium oxide -and sulfur dioxide.  These chemicals
can then be recombined directly  to produced magnesium
bisulfite acid for cooking"  (25).  Sulfite Flow
Diagrams No, 1 and 3 show variations of such  a process.
A thorough discussion of the recovery process principles
may be found in "The Pulping of  Wood"  (25).

The sulfur dioxide produced in the recovery  furnace  is
carried out and through a dust collector before  entering
the direct contact evaporator.   These  evaporators  are
designed to prevent absorption of the  SO   in  the evaporating
liquor, so that all SO  may be sent  to the  absorption
tower.
                             4-57

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         The venturi absorption towers absorb the sulfur dioxide
         with a solution of magnesium hydroxide.  Sulfur dioxide
         enters the towers from the recovery furnace as well as
         from the fortification towers, and/or the digester.
         Magnesium hydroxide readily absorbs the sulfur dioxide.
         Absorption efficiencies of the venturi absorption systems
         range from 95 - 98+ percent.  Sulfur dioxide emissions
         from the absorption system range from 10 - 25 Ib/ADT
         of pulp.

         "At present there is no process in commercial operation
         for the recovery of pulping chemicals from ammonium-base
         spent cooking liquors" (26).  Many ammonium acid sulfite
         mills simply incinerate their waste liquors in combination
         boilers to recover the heating value of the liquor.  Such
         a system is demonstrated in Sulfite Flow Diagram No. 4.
         Sulfur dioxide emissions from such incinerators are in the
         range of 250 - 500 Ib/ADT.

         Sulfur trioxide emissions from recovery furnaces and
         incinerators are possible if close control is not taken
         over the excess oxygen in the flue gases as well as its
         temperature.  A common means for controlling SO_ formation,
         other than oxygen control, is the use of cooling towers
         which cool the sulfur dioxide below the temperature required
         for conversion to sulfur trioxide.  Quantitative data of
         the emission of sulfur trioxide are not available.
4.5.2.4  Emissions from Multiple-Effect Evaporators

         Multiple-effect evaporators which concentrate spent liquors
         are a source of sulfur dioxide emissions.  Such emissions
         are evolved because of the high temperature and low pressure
         conditions in the effects.  The type of condenser has an
         effect on the sulfur dioxide emissions.  Adequate contact
         between the sulfur dioxide and the cooling water will remove
         a large portion of the gas.

         Sulfur dioxide emissions from the multiple effect evaporators
         are in the range of 5 - 10 Ib/ADT of pulp.
                                        4-58

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4.6  AUXILIARY FURNACES

     The atmospheric emissions of sulfur dioxide and fly ash
     from auxiliary furnaces are directly dependent upon the
     amount of sulfur bearing fuels which are burned in the
     furnace.  The amount of energy which must be provided
     by the auxiliary furnaces is directly dependent upon
     the total energy requirements of a mill and the amount
     of this energy which can be furnished by the recovery
     system.  This energy demand on the auxiliary furnace
     is highly individualistic for each pulp and paper mill.

     A common source of fuel for auxiliary furnaces is wood
     bark.  Bark has a heating value of approximately
     4,500 BTU/lb., and is readily available in mills which
     use roundwood.  Bark burning produces very little
     sulfur dioxide; approximately 1 Ib.SO /1000 Ibs. bark.
     Fly ash from bark burning is in the range of approximately
     10 - 20 Ib. ash/1000 Ibs. bark.

     Fuel oil is another common fuel used in auxiliary furnaces.
     Fuel oil contains varying percentages of sulfur which forms
     sulfur dioxide in the oxidizing atmosphere of the furnace.
     Fuel oil has a heating value of approximately 19,000 BTU/lb.
     The quantity of sulfur dioxide formed in the combustion
     of fuel oil, assuming efficient combustion, depends mainly
     upon the sulfur content of the oil, which is usually in
     the range of 1 - 6 percent.  A convenient formula for
     determining the amount of sulfur dioxide produced in the
     combustion of fuel oil is:

                pound SO  formed  _  pounds sulfur     2 pounds SO    1nnn
          _             ^         ~                 X             ^ X J-U \J \J
          1000  	;	r:	,    		::	r,    	=	' ., ,.
                pounds oil burned    pound fuel oil    pound sulfur

     The fly ash formation of fuel oil ranges from 0.9 - 1.0 Ibs.
     ash/1000 Ibs oil.

     Coal is another fuel used in auxiliary furnaces.  Coal has
     a heating value of 14,000 BTU/lb.  Like fuel oil, the sulfur
     content of coal is usually in the range of 1 - 6 percent.
     The quantity of sulfur dioxide formed in the combustion of
     coal may be found by using the equation shown above.  The
     fly ash produced by burning coal is higher than that of fuel
     oil, and is in the range of 60 - 80 lbs/1000 Ib coal.

     Natural gas is another fuel which is now being used to a
     limited extent for auxiliary furnaces.  Its heating value
     is 1,000 BTU/ft .  The sulfur and ash content of natural
     gas may be considered negligible.
                                4-59

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Table 4-17 summarizes the data.
                         TABLE  4-17

      SULFUR DIOXIDE AMD FLY ASH PRODUCTION FROM THE COMBUSTION
          OF ASSORTED FUELS IN AN AUXILIARY FURNACE

                       SO                  Fly Ash
                (lb/1000 Ibs fuel)       (lb/1000 Ibs fuel)
Bark                  1.0 - 1.5              10 - 20

Oil (2% S)            40                    0.9 - 1.0

Coal (2% S)           40                     60 - 80

Natural Gas           Trace                  Trace
Because of the varied power requirements placed upon the auxiliary
furnaces by the assorted pulping and paper making systems, it
is beyond the scope of this chapter to attempt to give emissions
of sulfur dioxide and fly ash from the auxiliary furnaces in
terms of pounds per air dry ton of pulp.  However the flow diagrams
and the associated heat and energy balances presented in Chapter
3, may give the reader an idea of the energy requirements placed
on the auxiliary furnace.  The flow diagrams show how these
requirements can be satisfied using the fuels discussed here, and
the emissions of sulfur dioxide and fly ash which might result.
                             4-60

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4.7  SUMMARY OF EMISSION DATA

     Table 4-18 summarizes the approximate ranges of emissions for
     the principle gaseous sulfur compound-and particulate emissions
     from the kraft pulping and recovery system.  Table 4-19 summarizes
     the approximate ranges of sulfur dioxide and fly ash formation
     in the combustion of fuels in the auxiliary furnaces.

     Because of the variety and complexity of the pulping and
     recovery systems used in the sulfite and NSSC processes,
     a meaningful table cannot'- be presented here.  The reader is
     referred to the flow diagrams in Chapter Three to obtain the
     emissions of a particular system.
                                  4-61

-------
i
(T>
to
                                                  TABLE  4-18

                                       SUMMARY OF EMISSION DATA - KRAFT PROCESS

                                                  (Emissions in Ib/ADT)
       Digester Relief & Blow

       Brown Stock Washers

       Oxidation Towers
                                     so2

                                    T - 0.01

                                 0.01 - 0.02

                                    0 - 0.01
Multiple Effect Evaporators OX.  0.01

                          UNOX.     0 - 0.01

Direct Contact Evaporators  OX.   2.0-8.0

                          UNOX.   2.0 - 8.0

Recovery Furnace                   10 - 15

Smelt Tank                        0.0 - 0.01

Lime Kiln                          DATA
0.01 -

0.01 -

0.01 -

0.01 -

0.10 -

0.10 -

 5.0 -

 1.0

0.02

NOT
                                     MeSSMe

                                   0.20 - 1.50

                                   0.01 - 0.02
                                                                                                            Particulate
;          MeSH       MeSMe

0.12  0.02  - 0.40   0.40  - 2.5

0.12  0.10  - 0.25   0.01  - 0.02

0.02  0.05  - 0.10   0.02  - 0.08   0.05  - 0.15

0.02  0.10  - 0.30   0.05  - 0.15   0.05  - 0.15

3.0   0.10  - 1.50   0.05  - 0.08   0.01  - 0.02
  2.0   0.05 - 0.25  0.01 - 0.10   0.01 -'0.20  75-125(cascade)
                                                20-40  (venturi)
- 30.0  0.50 - 2.50  0.10 - 0.30   0.10 - 0.40  75-125(cascade)
                                                20-40  (venturi)
- 5.0   0.01 - 0.10  0.01 - 0.02   0.01 - 0.02
                                                           - 0.05  0.02 - 0.05  0.01 - 0.02
                                      0 - 0.01  1.0  -  4.0
                                                              AVAILABLE  -  TRS - 0.01 - 0.83
                                                 20  -  65

-------
                         TABLE  4-19

           SUMMARY OF SULFUR DIOXIDE-AND FLY ASH FORMATION
                    IN AUXILIARY FURNACE COMBUSTION
                           SO                  Fly Ash


                    (lb/1000 Ib fuel)       (lb/1000 Ib fuel)
Bark                   1.0 - 1.5               10 -  20

Fuel Oil (2% sulfur)    40                    0.9-1.0

Coal (2% sulfur)        40                     60 -  80

Natural Gas             Trace                    Trace
                                 4-63

-------
4.8  REVIEW OF EMISSION STANDARDS APPLICABLE TO PULP MILLS

     A variety of emission regulations is in effect in many city,  county,
     regional, and s tate abatement areas in the U.S.  In addition  to
     general nuisance provisions, specific emission limitations  are
     in effect on particulates,  individual gaseous compounds,  and  classes
     of compounds.  Some of these limitations,  such as. emissions of
     particulates, sulfur dioxide, hydrogen sulfide, arid total reduced
     sulfur compounds (TRS)  may  be applied to chemical pulp mills.

     In some localities an attempt is made to apply to pulp mills  the
     process weight table originally developed in Los Angeles  County.
     This is an inappropriate application of the process weight  table
     which was developed for and applied to the metallurgical  industry.'.
     The process weight concept  represents the state of the art  on
     emissions control from metallurgical processes.  The nature and
     size range of particulates, as well as the characteristics  of the
     processes themselves, are vastly different from the recovery  and
     calcining operations involved in chemical pulping.

     As of late 1969, in states  where pulp mills are located,  regulations
     specific to pulp mills  were to be found in Washington, Oregon, and
     Humboldt County, California.  In all cases the rules are  applicable
     to kraft mills only.

     Provisions of the Washington and Oregon regulations are identical
     with respect to emission limitations.  All limitations are  stated
     per ton of air dry pulp produced.  Principal provisions of  the
     regulations include:

         (a)   TRS Compounds  from the recovery furnace:  No
              more than 2 pounds per ton (1972)  reduced to
              no more than 1/2 pound per ton by 1975.

         (b)   Noncondensible gases from the digesters and
              multiple effect evaporators:  Collected and
              burned in the  lime kiln or proven equivalent.

         (c)   Particulates from  the recovery furnace:  No
              more than 4 pounds per ton.

         (d)   Particulates from  lime kiln:  No  more than
              1 pound per ton.

         (e)   Particulates from  smelt tank:   No more than
              1/2 pound per  ton.
                                     4-64

-------
The principal provisions of the Humboldt County regulations
specific to pulp mills include:

     (a)  TRS compounds from any single emission point:
          No more than the total daily weight calculated
          by the formula:
                                               - 2
               TRS (pounds per day) = 0.012 (H )
                                              s
          where H,  is the height in feet of the emission
          point above mean ground elevation.

     (b)  Total maximum allowable monthly TRS emissions
          to the atmosphere:  No more than one pound
          per ton of dry wood charged into the [pulping]
          process.

     (c)  Maximum allowable ground level concentration of
          TRS, expressed as HS:  No more than 0.03 ppm
          for no longer than 60 minutes.

In Washington and Oregon (29) the regulations were developed in
cooperation with representatives of the kraft pulping industry.
The most important sources of odors and paocticulates weze
identified, the state of the art in emissions control was
determined, and developments in new technology were assessed.
The regulations consider best available technology and uniqueness
of process.

The states of Washington and Oregon presently are developing
regulations for atmospheric emissions from sulfite mills.

By mid-1970, Air Quality Regions called for by the Air Quality
Act of 1967 will be designated in all of the states.  The
criteria and control documents for SO  and particulates have
been published by NAPCA.  Thus more stringent SO  and particulate
emission standards would appear inevitable under this program.
Present plans by NAPCA call for publication of some 35 criteria
documents (including one for odors) by 1975.  Application of
emission standards in the states should follow within about 15
months of publication.
                               4-65

-------
4.9  REFERENCES

     1.  CederLSf, R.,  Edfor,  M.  L.,  Friberg,  L., Lindvall, T., Nordisk
          Hygenish Tidskrfit 46,  51,  (1965).

     2,  Leonardia, G. , Kendall,  D.,  Barnard,  N., "Odor Threshold Determinators
         of 53 Odorant  Chemicals" J.  APCA 19  (2), 91-5,  (1969).

     3.  Young, F. A.,  Adams,  D.  R.,  Sullivan, Dobbs,  "The Relationship
         between Environmental-Demographic Variables and Olfactory Detection
         and Objectionability  Thresholds" to be published in Perception and
         Ps chophysics.

     4.  "Handbook of Air Pollution"  U. S. Department  of H.E.W., P.H.S.,
         Bureau of State Services. Division of Air Pollution, Cincinnati,
         Ohio.

     5  "The Merck Index"  8th Edition, Merck  and Co., Inc., Rahway,
         N.  J., 1968.

     6.  Douglass/ I. B., "Some Chemical  Aspects of Kraft Odor Control",
         J.  APGA 18 (8)/  543,  (1968)

     7.  McKean,  W.  R., Hrutfiord, B. F., Sarkanen, K. V., "Effect of
         Kraft Pulping  Conditions on  the  Formation of Methyl Mercaptan
         and Dimethyl Sulfide," TAPPI, 50_ (8) , 400-05, (1968)

     8.  McKean,  W.  R., Hrutfiord, B. F., Sarkanen, K. V., "Kinetic Analysis
         of Odor Formation  in  the Kraft Pulping Process," TAPPI, 48_ (12) ,
         699-703,  (1965).

     9.   Shih,  T.  T., Hrutfiord, B. F., Sarkanen, K. V,, Johanson, L. N.,
         "Methyl  Mercaptan  Vapor-Liquid Equilibrium in Aqueous Systems
         as  a Function  of Temperature and pH'," TAPPI,  5 (12), 634-8, (1967).

   10.   Murray, F. E., Rayner, H. B., "The Emission of Hydrogen Sulfide
         from Kraft Recovery Furnaces," Pulp and Paper Magazine of Canada,
         69_ (5) ,  71-4,  (1968) .

   11.   Blosser,  R. O., Cooper, H. B., Megy, J. A., Duncan, L., Tucker,
         T. w.,  "Factors Affecting Gaseous Sulfur Emissions in the Kraft
         Recovery  Furnace Complex," Paper Trade Journal 153 (21), 58-59,
         (1969) .
                                     4-66

-------
12.  Harding, C.  I., Landry,  J.  O.,  "Future Trends in Air Pollution
     Control in the Kraft Pulping Industry," TAPPI, 4_9_  (8), 61-7a,
     (1966).

13.  Thoen,  G. N.,  DeHaas, G. G., Tallent, R. G., Davis, A. S., "The
     Effect  of Combustion Variables  on  the Release of Odorous Sulfur
     Compounds from a Kraft Recovery Unit," TAPPI, 5.1  (8), 329-33,
     (1968).

14.  Murray, F. E., Rayner, H. B., "Emission of  Hydrogen Sylfide
     from Kraft Black Liquor  during  Direct-Contact Evaporation,"
     TAPPI,  48_ (10), 588-92,  (1965).

15.  "The Pulping of Wood," MacDonald,  R. G., Volume I, Second
     Edition, McGraw Hill Book Company, New York,  (1969).

16.  Ibid, page 455.

17.  Ibid, page 478.

18.  McKean, W. T., Hrutfiord, B. F., Sarkanen,  K. V.,  "Kinetics
     of Methyl Mercaptan and  Dimethyl Sulfide Formation in Kraft
     Pulping," TAPPI, _51 (12), 564-7, (1968).

19.  Taylor, C. E., "Lime Kilns and Their Operation,"  in Atmospheric
     Emissions from Sulfate Pulping, (E. R. Hendrickson, Editor),
     April 1966.

20.  Harding, C.  I., "Source  Reduction in the Pulping  Industry,"
     presented at the Fifth Annual Sanitary  and Water  Resources
     Engineering Conference,  Vanderbilt University,  June  2-3,  1966.

21.  "The Pulping of Wood," MacDonald,  R. G., Volume I, Second
     Edition, McGraw Hill Book Company, New  York,  1969, page 227-29.

22.  Ibid, page 61.

23.  Ibid, page 278.

24.  Ibid, page 324-5.

25.  Ibid, page 341-3.
                                 4-67

-------
26.  Ibid, page 341.

27.  Warther, J. F., Amberg, H.  R.,  "The Status  of Odor Control  in the
     Kraft Pulp Industry," presented at National AIChE  Meeting,  Portland,
     August 1969.

28.  Shih, T. T., Hrutfiord, B.  F.,  Sarkanen,  K. V.,  Johanson, L. N.,
     "Hydrogen Sulfide Vapor-Liquid  Equilibrium  in Aqueous  Systems As
     A Function of Temperature and pH," TAPPI, 50_ (12), 630-4,  (1967) .

29.  Hildebrandt, P. W.,  Droege, H., and Stockman, R. L.,  "Development
     of Regulations for Atmospheric  Emissions  from Kraft Pulp Mills,"
     presented at National AIChE Meeting, Atlanta, February 1970.
                                      4-68

-------
                          APPENDIX  A
     Appendix A  consists of seven tables.  Table A-l summarizes
the number of pulp mills and pulp production by process for each
state.

     Table A-2 presents specific data for each mill within a
given state.  The pulp tonnage listed in the columns headed
Unbleached  (Unbl.) is the total tonnage of all air dry pulp pro-
duced at a mill by~ a particular pulping process.  The tonnage
listed in the columns headed Bleached (Bl.) is that portion of
the total tonnage which is bleached and is expressed in finished
bleached tons.  For example:

                                                 Kraft
              County           Owner          Unbl.    Bl.

           Little River    Nekoosa-Edwards     430     400
                           Paper Company

means that the entire output of 430 unbleached tons was probably
used to produce 400 finished bleached tons.  Since a shrinkage
(pulp loss) of approximately 5-10 percent is experienced from
unbleached to finished bleached pulp, this should be a reasonable
assumption

Jesup      Wayne           ITT, Rayonier       675     675

means that the mill reported the same tonnage for unbleached and
bleached.  These tonnages have been tabulated as received from the
mill; whereas, in actual practice there should be a difference
between the two numbers.

     Mill age has not been included in these tabulations since many
of the older mills have been modified to such an extent that the
original mill age has little relation to the technological age of
the mill.

     Table A-3 contains detailed historical data presented in
support of Figure 2-3.

     Tables A-4 through A-7 present detailed data in support of
Table 2-3.
                           A-l

-------
                                                         TABLE   A-l

                                          SUMMARY  OF  CHEMICAL  WOOD  PULP  MILLS  IN  U.  S.
                                                      AS  OF DECEMBER 1968
>
      LOCATION
  STATE
Alabama
Alaska
Arizona
Arkansas
California
Colorado
Connecticut
Delaware
District of Columbia
Florida
Georgia
Hawaii
Idaho
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Maine
Maryland
Massachusetts
Michigan
Minnesota
Mississippi
Missouri
Montana
                                       NUMBER OP PULP MILLS AND PULP CAPACITY IN AIR DRY TONS PER DAY

NO
12
-
1
7
5
9
11
1
_
-
_
9
6
1

2
2
4
KRAFT
AD TPD
9,470
-
320
3,820
2,015
8,710
12,235
840
_
-
_
7,966
2,505
740
-
440
575
4,405
SULFITE
NO. AD TPD
-
2 1,340
-
-
-
1 375
- -
-
_ _
- -
_ _
-
4 1,290
-
-
1 168
1 135
-
SODA
NO. AD TPD NO.
_
_
_ _ _
_ _
- -
_
- - 2
- -
  2
- 1
- - 1
- - 4
w _ 0
_ _
1 54
- 3
- - 2
_ _
NSSC
AD TPD
-
-
-
-
-
-
600
-
370
110
200
915
360
-
-
770
360
-
                                          1,200

-------
                                            TABLE  A-1  (Continued)


                                KRAFT                   SULFITE                  SODA                   NSSC
  STATE                      NO.     AD TPD          NO.   AD TPD            NO.     AD TPD         NO.     AD TPD
Nebraska                      __             __                __             __
Nevada                        --             __                __             __
New Hampshire                 1         615           2       205             -                      2         445
New Jersey                    __             __                __             __
New Mexico                    --             --                --             -        -
New York                      1         205           2       160             1       155            4         611
North Carolina                4       4,440           -      -                -        -             2         570
North Dakota                  --             --                --             -        -
Ohio                          1         652           -      -                -        -             2         790
Oklahoma                      -                       -      -                -        -             1         420
Oregon                        6       4,745           5       765             -                      1         250
Pennsylvania                  5       1,235           2       350             1        86            1         385
Rhode Island                  --             --                --             -        -
South Carolina                4       4,860           -      -                -        -             2         725
South Dakota                  --             __                -_             -        -
Tennessee                     2       1,220           -      -                1       275            2         309
Texas                         5       3,780           -      -                -                      -
Utah                          --             --                --             --
Vermont                       --             __                _-             -        -
Virginia                      4       4,000           -      -                -        -             4        1,110
Washington                    8       5,560          12     4,515             -        -             3         510
West Virginia                 --             --                -        -             -        -
Wisconsin                     4       1,255          11     1,552             -                      2         865
Wyoming                       -         -             -      -                ~~             ~~
        TOTAL               116      87,808          43    10,875             4       570           43      10,675

-------
                                                        TABLE  A-2


                                      SUMMARY OF CHEMICAL WOOD PULP MILLS  IN EACH STATE

                                                     AS OF DECEMBER 1968
                   LOCATION
                                       KIND OF PULP MILLS AND AD: TPD CAPACITY
                                                                                 TYPE WOOD
I
J^





SOFT-
KRAFT SULFITE SODA NSSC WOOD
CITY

Brewton

Coosa Pines

Demopolis

Jackson
Mahrt
Mobile


Mobile
Montgomery
Naheola
Selma

COUNTY

Escambia

Talladega

Marengo

Clarke
Russell
Mobile


Mobile
Autauga
Choc taw
Dallas

OWNER

Container Corp.
of America
Kimberly-Clark
Corp.
Gulf States
Paper Corp.
Allied Paper, Inc.
Georgia Kraft Co.
International
Paper Co. , Sou.
Kraft Div.
Scott Paper Co.
Union Camp Corp.
American Can Co.
Hammermill
Paper Co.
Unbl.

900

630

400

520
900
1050


1400
870
970
430

Bl. Unbl. Bl. Unbl. Bl. Unbl.
ALABAMA
400

630

375

475
0
450


1300
0
900
400

Bl. %

75

64

60

40
90
77


73
93
60
75

HARD-
WOOD
%

25

36

40

60
10
23


27
7
40
25

    Pine Hill
Wilcox
MacMillan

Bloedel

United, Inc.
900
95

-------
                                                   TABLE   A-2  (Continued)
                                                   KRAFT
                                           SULFITE
                   SODA
NSSC
SOFT-   HARD-
WOOD    WOOD
CITY
Tuscaloosa
TOTAL ALABAMA
Ketchikan
Sitka
COUNTY OWNER Unbl. Bl. Unbl. Bl . Unbl. Bl. Unbl. Bl. %
Tuscaloosa Gulf States 500 0 90
Paper Corp.
Unbleached = 9470 000
Of Which Bleached = 4930
NUMBER OF MILLS 12 0 0 0
ALASKA
Ketchikan Pulp Co. 740 620 100
Alaska Lumber 600 500 100
& Pulp Co. , Inc.
%
10
0
0
TOTAL ALASKA
       Unbleached
Of Which Bleached
  NUMBER OF MILLS
1340
                                                                      1120

-------
                                          TABLE  A-2  (Continued)
                                                   KRAFT
                                           SULFITE
                                  SODA
                                                                                                   NSSC
SOFT-   HARD-
WOOD    WOOD
CITY
Snowf lake
TOTAL ARIZONA


Ashdown

Camden

Crossett
Morrilton

Pine Bluff
Pine Bluff

COUNTY OWNER
Navajo Southwest Forest
Industries, Inc.
Unbleached =
Of Which Bleached
NUMBER OF MILLS
Little River Nekoosa-Edwards
Paper Co.
Ouachita International
Paper Co . ,
Sou. Kraft Div.
Ashley Georgia-Pacific
Corp. , #1 Mill
#2 Mill
Conway Arkansas Kraft
Corp.
Jefferson Dierks Paper Co.
Jefferson International
Paper Co . ,
Sou. Kraft Div.
Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl. %
ARIZONA
320 65 100
320 0 0 0
65
1000
ARKANSAS
430 400 65

700 0 93

640 120 100
200 200 0
350 0 88

200 0 100
1300 1170 70

%
0


35

7

0
100
12

0
30

TOTAL ARKANSAS
       Unbleached
Of Which Bleached
  NUMBER OF MILLS
3820
                                                        1890
                                                     ,7.
                                                                                         Q-

-------
                TABLE  A-2 (Continued)

CITY
Anderson
Antioch
Antioch
Fairhaven
Samoa

KRAFT SULFITE
COUNTY OWNER Unbl. Bl . Unbl. Bl .
CALIFORNIA
Shasta Kimberly-Clark 165 150
Corp.
Contra Costa Fibreboard Corp. 500 160
Contra Costa Fibreboard Corp. 250 0
Humboldt Crown Simpson 550 500
Pulp Co.
Humboldt Georgia-Pacific 550 500
Corp.
TOTAL CALIFORNIA Unbleached = 2015 0


Fernandina
Beach
Fernandina
Foley
Of Which Bleached = 1310
NUMBER OF MILLS 5 0
FLORIDA
Nassau Container Corp. 825 0
of America
Nassau ITT Rayonier 375 375
Taylor The Buckeye 950 860
SOFT- HARD-
SODA NSSC WOOD WOOD
Unbl. Bl. Unbl. Bl. % %;
100 0
100 0
85 15
100 0
100 0
0 0

0 0
95 5
100 0
85 15
Cellulose Corp.

-------
                                                 TABLE  A-2  (Continued)
CO


CITY COUNTY

Jacksonville Duval

Jacksonville Duval

Palatka Putnam

Panama City Bay


Pensacola Escambia

Port St. Joe Gulf
TOTAL FLORIDA




KRAFT SULFITE
OWNER Unbl. Bl. Unbl. Bl .
FLORIDA (Continued)
Alton Box 675 0
Board Co.
St. Regis 1300 0
Paper Co.
Hudson Pulp & 950 400
Paper Corp.
International 1410 735
Paper Co. ,
Sou. Kraft Div.
St. Regis Paper 300 260
Co. - West Mill
St. Joe Paper Co. 1700 500
Unbleached = 8710 375
Of Which Bleached = 2755 375
NUMBER OF MILLS 9 1
GEORGIA
SOFT- HARD-
SODA NSSC WOOD WOOD
Unbl. Bl. Unbl. Bl. % %

90 10

60 40

60 40

50 50


88 12

90 10
0 0

0 0

   Augusta
Richmond
   Brunswick     Glynn
Continental Can
Co., Inc.

Brunswick Pulp
& Paper Co.
 750    700


1290   1195
60


61
40


39

-------
                                        TABLE  A-2 (Continued)
    CITY
COUNTY
Cedar Springs Early
Cedar Springs Early
Jesup
Macon
Port
Wentworth
Riceboro
Rome
St. Marys
Savannah
Savannah
Valdosta
Wayne
Bibb
Chatham
Liberty
Floyd
Camden
Chatham
Chatham
Lowndes
TOTAL GEORGIA
OWNER
             Great Northern
             Paper Co.
             Great Northern
             Paper Co.
             ITT Rayonier, Inc.  675
             Georgia Kraft Co.
             Continental Can
             Co., Inc.
             Interstate Paper
             Corp.
             Georgia Kraft Co.
             Gilman Paper Co.
             Union Camp Corp.
             Union Camp Corp.
             Owens-Illinois
             Inc.
KRAFT SULFITE
Unbl. Bl. Unbl. Bl.
GEORGIA (Continued)
1700 0

675 675
875 0
625 0
450 0
1500 0
900 350
2700 0

770 0
SOFT-
SODA NSSC WOOD
Unbl. Bl. Unbl. Bl. %
99
300 0 0
90
85
95
95
90
80
95
300 0 0
95
HARD-
WOOD
%
1
100
10
15
5
5
10
20
5
100
5
             Unbleached
      Of Which Bleached
        NUMBER OF MILLS
         =  12,235
                                                         2,920
                                                                                              600
                                                     11

-------
                                              TABLE  A-2 (Continued)
KRAFT SULFITE
CITY COUNTY OWNER Unbl. Bl. Unbl. Bl .
IDAHO
Lewiston Nez Perce Potlatch Forests, 840 800
Inc.
TOTAL IDAHO Unbleached = 840 0
Of Which Bleached = 800
NUMBER OF MILLS 1 0
> INDIANA
H
O
Carthage Rush Container Corp.
of America
Terre Haute Vigo Weston Paper
S Mfg. Co.
SOFT- HARD'
SODA NSSC WOOD WOOD
Unbl. Bl. Unbl. Bl. % %
100 0
0 0
0 0
120 0 0 100
250 0 0 100
TOTAL INDIANA
       Unbleached
Of Which Bleached
  NUMBER OF MILLS
0

0
0

0
0

0
370

  2

-------
TABLE  A-2 (Continued)
CITY
Fort Madison
TOTAL IOWA
1
j
j
Hawesville
TOTAL KENTUCKY
COUNTY OWNER
Lee Consolidated
Packaging Corp.
Unbleached =
Of Which Bleached
NUMBER OF MILLS
Hancock WesCor Corp .
Unbleached =
Of Which Bleached =
NUMBER OF MILLS
SOFT- HAR&
KRAFT SULFITE SODA NSSC WOOD WOOD
Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl. % %
IOWA
110 0 0 100
000 110
0
0001
KENTUCKY
200 0 0 100
000 200
0
0001

-------
                                        TABLE  A-2  (Continued)
                                                                                                           SOFT-   HARD-
CITY

Bastrop
Bastrop
Bogalusa
Bogalusa
H Elizabeth
NJ
Hodge
Hodge
Pineville
Port Hudson
St. Francis-
ville
Springhill
COUNTY
(Parish)
Morehouse
Morehouse
Washington
Washington
Allen
Jackson
Jackson
Rapides
E . Baton Rouge
West Feliciana
Webster
KRAFT SULFITE
OWNER Unbl. Bl . Unbl. Bl.

LOUISIANA
International Paper
Co., Sou. Kraft Div.
Bastrop Mill
International Paper 1200 1100
Co., Sou. Kraft Div.
Louisiana Mill
Crown Zellerbach 1350 140
Corp.
Crown Zellerbach
Corp.
Calcasieu Paper 250 0
Co . , Inc .
Continental Can 500 0
Co . , Inc .
Continental Can
Pineville Kraft 850 0
Corp.
Louisiana Forest 550 510
Products Corp.
Crown Zellerbach 550 500
Corp.
International 1650 1000
SODA NSSC WOOD
Unbl. Bl. Unbl. Bl. %

485 0 0
45
99
150 0 0
90
100
200 0 0
100
15
60
70
WOOD
%

100
55
1
100
10
0
100
0
85
40
30
                              Paper Co.,
                              Sou.  Kraft  Div.
W. Monroe
Ouachita
Olinkraft, Inc.
                                                  1066
                                                                                                            77
                                                                                                      23

-------
T A B'L E  A-2 (Continued)-  .
CITY
W. Monroe
W. Monroe
TOTAL LOUISIANA
Augusta
Cumberland
Mills
East
Millinocket
Jay
Lincoln
KRAFT SULFITE
COUNTY OWNER Unbl. Bl. Unbl. Bl.
LOUISIANA (Continued)
Ouachita Olinkraft, Inc. 1066 0
Ouachita Olinkraft, Inc.
Unbleached = 7966
Of Which Bleached = 3250
NUMBER OF MILLS 9 0
MAINE
Kennebec Statler Tissue 125 125
Corp .
Cumberland S. D. Warren Co. 270 250
Penobscot Great Northern
Paper Co.
Franklin International '525 470
Paper C,o.
Penobscot Lincoln Pulp 225 210
SOFT- HARD-
SODA NSSC WOOD T-70OD
Unbl. Bl. Unbl. Bl. % %
77 23
80 0 0 100
915
0
0 4
85 15
30 70
160 0 0 100
65 35
0 100

-------
                                                  TABLE   A-2  (Continued)
CITY
Millinocket
Old Town
Old Town
Rumford
Wins low
Woodland
Woodland
TOTAL MAINE
Luke
KRAFT SULFITE SODA NSSC
COUNTY OWNER Unbl . Bl. Unbl. Bl. Unbl . Bl. Unbl . Bl.
MAINE (Continued)
Penobscot Great Northern 500 0
Penobscot Penobscot Co. 375 350
Penobscot Penobscot Co. 215 200
Oxford Oxford Paper Co. 560 525
Kennebec Scott Paper Co. 450 415
Washington Georgia-Pacific 550 500
Corp.
Washington Georgia-Pacific 200 0
Corp.
Unbleached = 2505 1290 0 360
Of Which Bleached = 2305 740 0
NUMBER OF MILLS 64 02
MARYLAND
Allegany West Virginia 740'. 740
Pulp & Paper Co.
SOFT- HARD-
WOOD WOOD
% %
100 0
10 90
100 0
35 65
75 25
70 30
0 100
30 70
TOTAL MARYLAND
       Unbleached
Of Which Bleached
  NUMBER OF MILLS
740
                                                            740

-------
                                                  TABLE  A-2 (Continued)
                                                        KRAFT
                                                    SULFITE
                                                                                       SODA
                                                                    NSSC
Ostego
Allegan
Corp.

Menasha
             170
                                                                                                          0'
                           SOFT    HARB
                           WOOD    WOOD
CITY COUNTY
Lawrence Essex
TOTAL MASSACHUSETTS
Of
I
Ul
Detroit Wayne
Filer City Manistee
Filer City Manistee
Muskegon Muskegon
Ontonagon Ontonagon
OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
MASSACHUSETTS
Oxford Paper Co. 54 50
Unbleached =00 54 0
Which Bleached = 50
NUMBER OF MILLS 001 0
MICHIGAN
Scott Paper Co.* 168 168
Packaging Corp. 200 184
of America
Packaging Corp. 375 0
of America
S. D. Warren Co. 240 225
Hoerner Waldorf 225 0
% %
0 100
90 10
50 50
0 100
36 64
0 100
                                                                                                      100
TOTAL MICHIGAN
                Unbleached
         Of Which Bleached
           NUMBER OF MILLS
                                                      440
                                168
                                                            409
                                       168
0

0
770

  3
*Shut down in 1969

-------
                                                  TABLE  A-2 (Continued.)
                                                                                                                 SOFT-   HARD-
CITY
Cloquet

Cloquet

Grand Rapids
International
Falls
St. Paul
KRAFT SULFITE SODA NSSC WOOD
COUNTY OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl. %
MINNESOTA
Carl ton The Northwest 325 305 60
Paper Company
Sub. of Potlatch
Forests, Inc.
Carlton The Northwest 135 125 10
Paper Company
Sub. of Potlatch
Forests, Inc.
Itasca Blandin Paper Co. 50 50 0
Koochiching Boise Cascade 250 250 50
Corp.
Ramsey Hoerner Waldorf 310 0 0
Corp.
WOOI
%
40

90

100
50
100
TOTAL MINNESOTA
       Unbleached   =

Of Which Bleached   =
  NUMBER OF MILLS
 575           135

          555          125
      2            1
                                                                                360
                                                                                                         50
                                                          MISSISSIPPI
Monticello
Lawrence
       St. Regis Paper
1690
                                                                                               100

-------
                                                TABLE  A-2  (Continued)
KRAFT SULFITE SODA NSSC
SOFT- HARD-
WOOD .WOOD
CITY COUNTY OWNER Unbl. Bl . Unbl. Bl . Unbl. Bl. Unbl. Bl. % '% -
MISSISSIPPI (Continued)
Moss Point Jackson International 730 660
Paper Co.
Sou. Kraft Div.
Natchez Adams International 1000 1000
Paper Co.
Sou. Kraft Div.
> Vicksburg Warren International 985 300
M Paper Co.
^ Sou. Kraft Div.
TOTAL MISSISSIPPI ' Unbleached = 4405. 0.0 0
Of Which Bleached = 1960
NUMBER OF MILLS 4 000
MONTANA
Missoula Missoula Hoerner Waldorf 1200 250
Corp.
55 45
19 81
85 15
100 0
TOTAL MONTANA
       Unbleached   =
Of Which Bleached   =
  NUMBER OF MILLS
1200
                                                            250

-------
                                                   TABLE  A-2  (Continued)
KRAFT
SULFITE
SODA
                                                                                   NSSC
00
CITY COUNTY
Berlin Coos
Berlin Coos
Groveton Coos
Groveton Coos
Lincoln Grafton
TOTAL NEW HAMPSHIRE
Deferiet Jefferson
Glens Falls Warren
Lyons Falls Lewis
Mechanicville Saratoga
OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
NEW HAMPSHIRE
Brown Company 615 500
Brown Company 220 0
Groveton Papers Co. 115 105
Groveton Papers Co. 225 0
Franconia Paper 90 90
Corp.
Unbleached = 615 205 445
Of Which Bleached = 500 195 0
NUMBER OF MILLS 12 2
NEW YORK
St. Regis Paper Co. 100 60
Finch, Pruyn & 237 178
Co. , Inc.
Georgia-Pacific Corp. 120 120
West Virginia 184 158
Norfolk
                Pulp & Paper Co.
St. Lawrence    Northland Paper
                                                                                                                SOFT-
                                                                                                                WOOD
                                                                                                                 35
                                                                                                                  0
                                                                                                                100
                                                                                                                  0
                                                                                                                100
                                                                        60
                                                                                                                 100
                                                                                                                   0

                                                                                                                   0
                                                                                                                   0

                                                                                                                 100
                                                                                                                          HARD-
                                                                                                                          WOOD
                                                                                                                            65
                                                                                                                           100
                                                                                                                             0
                                                                                                                           100
                                                                                                                             0
                                                                                                                             0
                                                                                                                           100

                                                                                                                           100
                                                                                                                           100

-------
                                                  TABLE  A-2 (Continued)
CITY
North
Tonawanda
Plattsburgh
Ticonderoga
i
H
VO
KRAFT SULFITE SODA NSSC
COUNTY OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
NEW YORK (Continued)
Niagara International 155 155
Paper Co.
Clinton Georgia Pacific 70 0
Corp.
Essex International 205 190
Paper Co.


SOFT- HARD-
WOOD WOOD
% %
0 100
0 100
0 100

TOTAL NEW YORK
       Unbleached
Of Which Bleached
  NUMBER OF MILLS
205
                                                                     160
155
611
      190
                                                                              60
       155
      456

-------
TABLE  A-2 (Continued)
      KRAFT
SULFITE
SODA
                                                   NSSC
SOFT-  HARD-
WOOD   WOOD
CITY COUNTY

Canton Haywood


Plymouth Washington
Plymouth Washington
Riegelwood Columbus
Roanoke Rapids Halifax

Sylva Jackson
TOTAL NORTH CAROLINA
Of
OWNER Unbl. Bl. Unbl. Bl. Unbl .
NORTH CAROLINA
U.S. Plywood - 1290 1290
Champion Papers ,
Inc.
Weyerhaeuser Co. 1180 450
Weyerhaeuser Co.
Riegel Paper Corp. 1070 1000
Hoerner Waldorf 900 0
Corp.
The Mead Corp.
Unbleached = 4440 0
Which Bleached = 2740
NUMBER OF MILLS 4 1

Chillicothe Ross
Circleville Pickaway

Coshocton Coshocton

TOTAL OHIO
Of

OHIO
The Mead Corp. 652 600
Container Corp.
of America
Stone Container
Corp .
Unbleached = 652 0 0
Which Bleached = 600
NUMBER OF MILLS 1 0
Bl. Unbl. Bl. % %

60 40


80 20
300 0 0 100
50 50
88 12

270 0 0 100
570
0
0 2

0 100
240 0 0 100

550 0 0 100

790
0
0 2

-------
TABLE  A-2 (Continued)


CITY

Broken Bow
TOTAL OKLAHOMA

i
j
j
Albany

Coos Bay

Gardiner

Jordan Cove

KRAFT SULFITE SODA NSSC
COUNTY OWNER Unbl. Bl . Unbl. Bl. Unbl. Bl. Unbl. Bl.
OKLAHOMA
McCurtain Dierks Forests, Inc. 420 0
Unbleached =0 0 0 420
Of Which Bleached = 0
NUMBER OF MILLS 00 01
OREGON
Linn Western Kraft 500 0
Corp.
Coos Coos Head 90 0
Timber Co.
Douglas International 545 0
Paper Co.
Coos Menasha Corp. 250 0
SOFT- HARD
WOOD WOOD
% %

100 0



100 0

100 0

100 0

0 100

-------
                                                     TABLE  A-2 (Continued)
NJ
CITY
Lebanon
Newberg
Oregon City
St. Helens
Salem
Springfield
Toledo
Wauna
TOTAL OREGON
KRAFT SULFITE SODA NSSC
COUNTY OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
OREGON (Continued)
Linn Crown Zellerbach . 105 0
Corp.
Yarnhill Publishers'
Paper Co .
Clackamas Publishers' 170 100
Paper Co.
Columbia Boise Cascade 800 650
Corp.
Marion Boise Cascade 220 210'>
Corp.
Lane Weyerhaeuser 1150 0
Corp.
Lincoln Georgia Pacific 950 0
Corp.
Clatsop Crown Zellerbach 800 550
Corp.
Unbleached = 4745 ' 765 0 250
Of Which Bleached = 1200 310'- 0
NUMBER OF MILLS 65 01
SOFT- HARD-
WOOD WOOD
% %
100 0
100 0
100 0
100 0
100 0
100 0
100 0
85 15

-------
                                                    TABLE  A-2 (Continued)
10
CITY COUNTY
Erie Erie
Johns onburg Elk
Johnsonburg Elk
Lock Haven Clinton
Mehoopany
Roaring Blair
Springs
Spring Grove York
Tyrone Blair
Williamsburg Blair
KRAFT SULFITE SODA NSSC
OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
. . PENNSYLVANIA
Hammermill Paper 385 385
Co.
New York & Penn- 170 160
sylvania Co., Inc.
New York & Penn- 110 110
sylvania Co . , Inc .
Hammermill Paper 86 80
Co.
Charmin Paper "" 240 240
Products Co.
Combined Paper 195 180
Mills, Inc.
P. H. Glatfelter 550 500
Co.
Westvaco 160 152
Westvaco* 160 0
SOFT-
WOOD
%
0
0
100
0
0
50
50
30
0
HARD'
WOOD
%
100
100
0
100
100
50
50
70 -
100
  TOTAL PENNSYLVANIA
       Unbleached
Of Which Bleached
                                                       1235
350
                                                          86
385
                                                              992
       350
                                                                                              80
                                    385
  *Shut down in 1969

-------
TABLE  A-2 (Continued)
                                                               SOFT-  HARD-
CITY
Catawba
Charleston
Florence
Georgetown
Georgetown
Hartsville
TOTAL SOUTH
KRAFT SULFITE SODA NSSC
COUNTY OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
SOUTH CAROLINA
York Bowaters Carolina 860 860
Corp .
Charleston Westvaco 1850 0
Florence South Carolina 600 0
Industries, Inc.
Georgetown International 1550 340
Paper Co . ,
Sou. Kraft Div.
Georgetown International 325 0
Paper Co . ,
Sou. Kraft Div.
Darlington Sonoco Products 400 0
Co.
CAROLINA Unbleached = 4860 0 0 725
Of Which Bleached = 1200 0
NUMBER OF MILLS 4 0 02
WOOD WOOD
% %
88 12
80 20
90 10
79 21
0 100
0 100

-------
                                                  TABLE  A-2 (Continued)


CITY

Calhoun

Counce

Harriman
Kingsport
Knoxville


KRAFT SULFITE SODA NSSC
COUNTY OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
TENNESSEE
McMinn Bowaters Southern 520 490
Paper Corp.
Hardin Tennessee River 700 0
Pulp & Paper Co .
Roane The Mead Corp. 190 0
Sullivan The Mead Corp 275 260
Knox Southern Extract 119 0
Co.
SOFT- HARD-
WOOD WOOD
% %

100 0

91 9

0 100
0 100
0 100

TOTAL TENNESSEE
       Unbleached
Of Which Bleached
  NUMBER OF MILLS
                                                     1220
                                                         275
         309
                                                            490
260

-------
TABLE  A-2 (Continued)
CITY
Evadale
Houston
Lufkin
Mulford
I
o$?asadena
TOTAL TEXAS
Big Island
Covington
Covington
KRAFT SULFITE SODA NSSC
COUNTY OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
TEXAS
Jasper Eastex, Inc. 1200 1000
Harris Southland Paper 450 100
Mills, Inc.
Angelina Southland Paper 325 300
Mills, Inc.
Orange Owens-Illinois 1000 0
Inc.
Harris U. S. Plywood 805 805
Champion Papers , Inc .
Unbleached = 3780 0 0 0
Of Which Bleached = 2305
NUMBER OF MILLS 50 00
VIRGINIA
Bedford Owens-Illinois , Inc. 450 0
Alleghany Westvaco 950 850
Alleghany Westvaco 270 0
SOFT- HARD-
WOOD WOOD
% %
58 42
100 0
100 0
100 0
70 30
0 100
34 66
0 100

-------
                                                    TABLE  A-2 (Continued)
      CITY
  Franklin
  Hopewell

  Hopewell
  Lynchburg
  West Point
to
  TOTAL VIRGINIA
  Anacortes
  Bellingham
COUNTY
Isle of Wight
Prince George
Prince George
Campbell
King William
KRAFT SULFITE SODA NSSC
OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
VIRGINIA (Continued)
Union Camp Corp. 1100 940
Continental Can 900 0
Co. , Inc.
Continental Can 200 0
The Mead Corp. 190 0
The Chesapeake 1050 0
Corp. of Virginia
SOFT- HARD
WOOD WOOD
% %
43 57
100 0
0 100
0 100
88 12
Unbleached = 4000 0 0 1110
Of Which Bleached = 1790 0
NUMBER OF MILLS 40 04
WASHINGTON
Skagit
Whatcom
Scott Paper Co. 135 135
Georgia Pacific 530 500
5 95
100 0
                                    Corp.

-------
                                                  TABLE   A-2  (Continued)
    CITY
    COUNTY
       OWNER
   KRAFT
Unbl.   Bl.
                                                                      SULFITE
Unbl.
Bl.
Camas

Camas
Cosmopolis
Everett
Everett

Everett
Everett
Hoquiam
Longview
Longview
Longview
Longview
Longview
Millwood
Port Angeles
Port Angeles
Clark

Clark
Grays Harbor
Snohomish
Snohomish

Snohomish
Snohomish
Grays Harbor
Cowlitz
Cowlitz
Cowlitz
Cowlitz
Cowlitz
Spokane
Clallam
Clallam
         WASHINGTON (Continued)
Crown Zellerbach    780   780
Corp.
Crown Zellerbach
Weyerhaeuser Co.
Scott Paper Co.
Simpson Lee          85    80
Paper Co.
Weyerhaeuser Co.    440   400
Weyerhaeuser Co.
ITT Rayonier,Inc.
Longview Fibre Co. 1800   400
Longview Fibre Co.
Weyerhaeuser Co.    695   650
Weyerhaeuser Co.
Weyerhaeuser Co.
Inland Empire
Fibreboard Corp.
ITT  Rayonier,  Inc.
              420
              488
              850
      400
      400
      850
              360
              545
      310
      545
              425

               42
               70
              450
       400

        20
        65
       450
SOFT-
SODA NSSC WOOD
Unbl. Bl. Unbl. Bl. ' V
100
100
90
100
0
85
100
100
100
140 0 0
91
100
230 0 100
100
95
100
HARD-
WOOD
' "% '
0
0
10
0
100
15
0
0
0
100
9
0
0
0
5
0

-------
TABLE  A-2 (Continued)
                                                               SOFT-  HARD-
CITY
Port Towns end

Tacoma

Vancouver

Wallula

> Wallula
to
VD
TOTAL WASHINGTON


COUNTY OWNER
Jefferson Crown Zellerbach
Corp.
Pierce St. Regis Paper
Co .
Clarke Boise Cascade
Corp.
Walla Walla Boise Cascade
Corp.
Walla Walla Boise Cascade
Corp.
Unbleached =
Of Which Bleached
NUMBER OF MILLS
KRAFT SULFITE SODA NSSC
Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
WASHINGTON (Continued)
420 0 " 	 ~"

930 145

200 185

410 0

140 0
5560 4515 1 510
2375 4260 0
8 12 03
WOOD WOOD
% %
100 0

100 0

100 0

100 0

100 0



-------
                                                  TABLE  A-2 (Continued)
CITY
Apple ton
Brokaw
Green Bay
Green Bay
Green Bay
Kaukauna
Marinette
Mosinee
Nekoosa
Oconto Falls
Park Falls
COUNTY
Outagamie
Marathos
Brown
Brown
Brown
Outagamie
Marinette
Marathon
Wood
Oconto
Price
OWNER
Consolidated
Papers, Inc.
Wausau Paper
Mills Co.
American Can Co.
Charmin Paper
Products Co.
Green Bay
Packaging , Inc .
Thilmany Pulp
& Paper Co.
Scott Paper Co.
Mosinee Paper
Mills Co.
Nekoosa-Edwards
Paper Co.
Scott Paper Co
Kansas City
SOFT-
KRAFT SULFITE SODA NSSC WOOD
Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl. %
WISCONSIN
165 155 100
155 145 15
155 145 0
130 123 100
250 0 0
380 90 100
55 50 100
175 0 80
340 315 75
115 110 80
115 110 67
HARD-
WOOD
%
0
85
100
0
100
0
0
20
25
20
33
Peshtigo

Port Edwards
Marinette

Wood
Star Co.
Badger Paper
Mills, Inc.
Nekoos a-Edwards
Paper Co.
100

235
 90

225
75      25

 0     100

-------
TABLE  A-2 (Continued)
                                                               SOFT-  HARD-
CITY
Rhine lander
Rothschild
Tomahawk
Wisconsin
Rapids
TOTAL WISCONSIN
KRAFT SULFITE SODA NSSC
COUNTY OWNER Unbl. Bl. Unbl. Bl. Unbl. Bl. Unbl. Bl.
WISCONSIN (Continued)
Oneida St. Regis Paper Co. 217 200
Marathon American Can Co. 217 200
Lincoln Owens-Illinois 615 0
Inc.
Wood Consolidated 360 333 67
Papers , Inc .
Unbleached = 1255 1552 0 865
Of Which Bleached = 738 1463 0
NUMBER OF MILLS 4 11 02
WOOD WOOD
% %
100 0
0 100
0 100
33

-------
                            T A B L E  A-3

        ANNUAL PRODUCTION AND CONSUMPTION  OF CHEMICAL  WOOD  PULPS
                               IN U.S.A.
                              1937 - 1967

                        MILLIONS OF TONS OF PULP


Year
1937
1940
1945
1950
1953
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967


Kraft
2.1
3.7
-
7.5
9.4
11.3
12.1
11.9
12.3
13.8
14.6
15.4
16.3
17.5
20.1
21.5
22.4
22.8


Sulfite
1.8
2.3
-
2.4
2.3
2.6
2.7
2.6
2.4
2.5
2.6
2.6
2.6
2.7
2.7
2.7
2.8
2.7


NSSC
0.1
0.2
-
0.7
1.0
1.4
1.5
1.6
1.6
1.9
2.0
2.4
2.5
2.6
2.7
2.9
3.2
3.3


Dissolving
0.4
0.3
-
0.5
0.7
1.0
0.9
1.0
0.9
1.1
1.1
1.2
1.3
1.4
1.5
1.5
1.5
1.4


Soda
0.5
0.5
-
0.5
0.4
0.4
0.5
0.4
0.4
0.5
0.5
0.4
0.4
0.4
0.2
0.2
0.2
0.2
Total
Production
Chemical
Pulps
4.9
7.0
9.3
11.6
13.8
16.7
17.7
17.5
17.6
19.8
20.7
22.0
23.1
24.6
27.2
28.8
30.1
30.4

Year
1937
1940
1945
1950
1953
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
Net
Imports
1.9
0.6
4.1
2.0
1.7
1.3
1.4
1.2
1.4
1.6
1.0
1.0
1.3
1.0
1.0
1.4
1.5
1.2
                                   Consumption
                                   Chem. Pulps

                                       6.8
                                       7.6
                                      10.4
                                      13.6
                                      15.5
                                      18.0
                                      19.1
                                      18.7
                                      19.0
                                      21.4
                                      21.7
                                      23.0
                                      24.4
                                      25.6
                                      28.2
                                      30.2
                                      31.6
                                      31.6
    Consumption
Per Capita - Pounds

         105
         115
         151
         180
         194
         218
         226
         210
         216
         240
         240
         250
         261
         271
         295
         310
         320
         318
Source:  U. S. Bureau of Census
         U. S. Pulp Producers Association
         American Paper Institute
                                    A-32

-------
                                                      TABLE   A-4
                                                 CHEMICAL  WOOD PULP MILLS
                                                    SUPPLEMENTARY DATA
                                        CURRENT AND PLANNED NEW  PLANT. CONSTRUCTION
                                                 AS OF DECEMBER  31, 1968
CJ
00
   State


Alabama

Alaska

Arkansas

Florida
Idaho
Kentucky

Louisiana
Maine
Minnesota
New York
                               Owner
                          New - N
                          Exp.  E
U.S. Plywood-Champion
   Papers

U.S. Plywood-Champion
   Papers
Georgia-Pacific Corp.
Potlatch Forests, Inc.
Container Corp. of America
Potlatch Porests, Inc.
Westvaco
Western Kraft Corp.
Boise Cascade Corp.
Great Northern Paper Co.
Northwest Paper Co.
Finch, Pruyn & Co., Inc.
International Paper Co.
                                                    N
                                                    N
Kind of Pulp S Capacity - AD Tons/Day
Kraft          Sulfite           NSSC
500 Bl.

600
E
N
E
E
N
N
N
E
E
N
N
425 Bl
400 Bl
550
220
600 Bl
200 Bl
600

250 Bl
510 Bl
510 Bl
                                                                                            350
                                                                           480
Date on
Stream
 1970

 1973

 1970

 1971
 1969
 1970
 1969
 1970
 1969
 1971
 1970
 1970

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                                                  TABLE  A-4 (Continued)
w
    North Carolina

    Oregon
    Pennsylvania
    South Carolina
    Tennessee
    Texas
    Virginia
    Washington
    West Virginia
Georgia-Pacific Corp,*
Weyerhaeuser Corp
American Can Company
Hammermill Paper Co.
Kimberly-Clark Corp.
Inland Container Corp.
International Paper Co,
Union Camp Corp.
ITT Rayonier, Inc.
Milburn Corp.
    TOTAL - AD TONS PER DAY
    TOTAL - AD TONS PER YEAR - 350 DAYS
N
N
N
E
N
N
N
E
N
N
2
600 Bl.
300 Bl.

300 Bl.

650 650 Bl.
600 Bl.
300 Bl.

7,605
,662,000
200 1969
1970
1969
200 Bl. 1970
-
300 1970
1971
1970
-
250
830 1,300 = 9,735 Gra
290,000 455,000 = 3,407,000
     * Plans shelved in 1969
     Source:  Paper Trade Journal
             Pulp & Paper
            February  3, 1969
            December  16, 1969

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                                                       TABLE  A-5
Ul
Ul
   Location
South Carolina
Wyoming
Florida
Minnesota
Mississippi
Minnesota

Arizona
Texas
Texas
Missouri
Oklahoma
Michigan
                                                  CHEMICAL WOOD PULP MILLS
                                                     SUPPLEMENTARY DATA
                                              PROPOSED AND TENTATIVE NEW MILLS
                                                  AS OF DECEMBER 31, 1968
                           Owner
Tenneco Co.
State
Great Northern Paper Co.
Boise Cascade Corp.
Columbia Pulp & Paper Co.
Minnesota International
Pulp & Paper Co.
Ponderosa Paper Products,
Sabine Pulp s Paper Co.
Texas Newsprint Co.
Delta-New Madrid Paper Corp.
Dierks Forests, Inc.
Oxford Paper Co.
New - N
Exp'.-v E
N
N
N
N
N
N
Inc. N
N
N
p. N
N
N

TPD
-
500
300
500
350
-
-
-
300
-
-
400

Kind
Kraft
Bl. Kraft
Bl. Kraft
Kraft
Kraft
Newsprint
Sulfite
Bl. Kraft
Newsprint
Newsprint
-
Bl. Kraft

Stage
Study
Study
Study
Study
Deferred
Study
Planned
Planned
Study
Study
Proposed
Deferred
        Source:   Paper  Trade Journal
                 Pulp & Paper

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                           TABLE  A-6

                        CHEMICAL WOOD PULP  MILLS
                           SUPPLEMENTARY DATA

                    ESTIMATE OF PHASED OUT  OPERATIONS
                            1968 THROUGH 1970
        MILLS CLOSED DOWN
 In 1968
        (Tonnages not included in  1968  Mill Capacities)1
 Location
                   Sulfite
Soda
Kraft
NSSC
Maine
Minnesota
Oregon
Wisconsin
New York
Wisconsin

AD Tons per
May
Early
May
June


Total
350 Day
1968
1968
1968
1968
1968
1968

Year
125
180
210
130

190
835
292,000




60
(Tonnage
60
21,000





replaced by new kraft mill)
0 0
0 0
In  1969 and  1970  (Tonnages  included  in  1968 Mill Capacities)
Michigan    May     1969
New York            (1970)

Minnesota           1970
Washington  Feb.    1969
New York            1969
            Total
Ad Tons per 350 Day Year
                    168
                   (To be replaced by   205
                       New Mill)
                    135
                    200
                               (To be replaced
                                   by MgO)
                     235
503
176,000
0
0
205
72,000
235
82,000
Maine
Note:
Source:
In 1969  -  A 500 TPD Sulfite Sodium Base Mill will be converted
            to Magnesium Base.

Probably other Sulfite Mills using Sodium and Calcium Base
Processes will convert to other Processes, but announcements
have not been made up to this time.
This study  (Meakin)
                                 A-36

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                          TABLE  A-7
                       CHEMICAL WOOD PULP MILLS
                          SUPPLEMENTARY DATA

                    ESTIMATE OF PHASED OUT OPERATIONS
                              1970 TO 1980
State
Mas s achus e tt s
New Hampshire
New York
Oregon
Pennsylvania
Washington
Wisconsin
Number
Mills
1
2
2
2
2
3
7
Process and AD Tons per Day
Kraft Sulfite Soda NSSC
54
205
160
195
110 86
85 112
780
    Total

AD Tons per .
 350 Day Year
19
85
     30,000
1,562
      547,000
140
          49 ,-000
                            A-37

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