EPA -660/2-74-029
     April 1974
                        Environmental  Protection Technology Series
       Color  Characterization Before
       and
       After  Lime  Treatment
                                  Office of Research and Development
                                  U.S. Environmental Protection Agency
                                  Washington. DC 20460

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            RESEARCH REPORTING SERIES
Research reports of the  Office  of  Research  and
Monitoring,  Environmental Protection Agency, have
been grouped into five series.  These  five  broad
categories  were established to facilitate further
development  and  application   of   environmental
technology.   Elimination  of traditional grouping
was  consciously  planned  to  foster   technology
transfer   and  a  maximum  interface  in  related
fields.  The five series are:

   1.  Environmental Health Effects Research
   2.  Environmental Protection Technology
   3.  Ecological Research
   4.  Environmental Monitoring
   5.  Socioeconomic Environmental studies

This report has been assigned to the ENVIRONMENTAL
PROTECTION   TECHNOLOGY   series.    This   series
describes   research   performed  to  develop  and
demonstrate   instrumentation,    equipment    and
methodology  to  repair  or  prevent environmental
degradation from point and  -non-point  sources  of
pollution.  This work provides the new or improved
technology  required for the control and treatment
of pollution sources to meet environmental quality
standards.

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                                          EPA-660/2-74-029
                                          April 1974
   COLOR CHARACTERIZATION BEFORE AND

         AFTER LIME TREATMENT
                    By

                H.  S. Dugal
               R. M. Leekley
               J. W. Swanson
             Project S 800853
          Program Element 1BB037

              Project Officer

              Ralph H. Scott
   Chief, Paper and Forest Industries
  U.S. Environmental Protection Agency
 National Environmental Research  Center
        Corvallis, Oregon  97330
               Prepared for

   OFFICE  OF RESEARCH AND DEVELOPMENT
  U.S. ENVIRONMENTAL PROTECTION AGENCY
         WASHINGTON, D.C.   20460
For tale by the Superintendent o( Documents, U.S. Government Printing Office
            Washington, D.C. 20402 • PrlCO $2.15

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               EPA Review Notice
This report has been reviewed by the Environmental
Protection Agency and approved for publication.
Approval does not signify that the contents neces-
sarily reflect the views and policies of the
Environmental Protection Agency, nor does mention
of trade names or commercial products constitute
endorsement or recommendation for use.
                         ii

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                                ABSTRACT

Four effluents from two different sources  were  studied before  and  after
lime treatment (massive and stoichiometric).

The massive lime treatment process was found to remove 73 percent  color
and 53 percent total organic carbon (TOG)  from kraft  decker  effluent, and
96 percent color and 80 percent TOG from kraft  bleach caustic  extract.
The analysis of the solids from the decker and caustic effluents showed
respective reductions of 73 and 50 percent phenolic hydroxyls, 63  and
26 percent sugars, and 51 and l6 percent methoxyls by lime treatment.
Color bodies not removed by lime from the  decker effluent had  weight
average molecular weight (M^) < 200, higher OH  to C-H stretch  ratio,
higher carboxylate to aromatic ring ratio  and seemed  to have more  pro-
nounced carbonyl groups than the untreated color bodies.  Similarly,
color bodies not removed from the bleach caustic extract had My. <  HOO,
contained aliphatic acid-salt systems, pronounced carbonyl groups, lower
carboxylate to carbonyl ratio and chromophores  which  absorb  more below
220 nm.  In general, the massive lime treatment is  more effective  on
caustic extract than decker effluent.

The Btoichiometric lime treatment prowess  was found to remove  79 percent
color and 50 percent TOC from kraft decker effluent,  and 6k  percent color
and 30 percent TOC from the NSSC effluent.  The analysis of  the solids
from the decker and NSSC effluents showed respective  reductions of 76
and 25 percent phenolic hydroxyls, 31 and "negligible" percent sugars,
and 1*2 and 9.7 percent methoxyls by lime treatment.   Color bodies  not
removed by lime from the decker effluent had M^ < 500, higher  OH to C-H
stretch ratio, higher carboxylate to aromatic ring ratio and seemed to
have more pronounced carbonyl groups than the untreated color  bodies.
Color bodies not removed by lime from neutral sulfite semi chemical
(NSSC) effluent had M^ < 300, and showed no detectable differences in
character from the untreated color bodies.  In general, stoichiometric
lime treatment is more effective on decker than NSSC effluents.
                                   ill

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LIME TREATMENT WITH METAL IONS

Addition of 150 to 300 ppm FeCl3 with only 300-500 ppm lime removed
about 98 percent color from bleach caustic extract.  Over 50 percent
of the color left by conventional lime treatment processes could also
be removed by incorporating polyvalent metal ions with lime.  However,
below 1000 ppm of lime, the sludge obtained settled slowly.  More color
could be removed when metal ions were used with lime than when each was
used individually indicating that a "synergistic" effect exists.
                                   iv

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                                CONTENTS






Abstract                                                              iii




List of Figures                                                       vi




List of Tables                                                        x




Acknowledgments                                                       xiii




Sections




I        Conclusions                                                  1




II       Recommendations                                              3




III      Introduction                                                 5




IV       Massive Lime Treatment                                       11




V        Stoichiometric Lime Treatment                                77




VI       Lime Treatment with Metal Ions                               125




VII      Experimental                                                 151




VIII     References                                                   167




IX       Appendices                                                   169

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                                 FIGURES


Ho..

 1      Classification of Contents of the Report                      7

 2      Flow Diagram for Effluent Processing and Fractionation        9

 3      Absorptivity Values at pH 1.6 of Untreated Wastes from
          IPCO (Visible Region)                                      21

 U      Absorptivity Values of pH 1.6 of lime-Treated Wastes
          from IPCO (Visible Region)                                 22

 5      Absorptivity Values at pH 1.6 of Untreated Wastes from
          IPCO (UV Region)                                           23

 6      Absorptivity Values at pH 1.6 of Massive Lime-Treated
          Wastes from IPCO (UV Region)                               2U

 7      Color and Total Organic Carbon Removal of Wastes from
          IPCO by Lime Treatment                                     27

 8      Decrease in Absorptivity of Wastes from IPCO by Lime
          Treatment                                                  28

 9      Absorptivity Versus Wavelength (Ultraviolet Range) of
          Indulin-C and Untreated Kraft Decker Waste from IPCO       33

10      Absorptivity Versus Wavelength (Ultraviolet Range) of
          Indulin-C and Lime-Treated Kraft Decker Waste from IPCO    3U

11      Absorptivity Versus Wavelength (Visible Range) of
          Indulin-C and Untreated Kraft Decker Waste from IPCO       35

12      Absorptivity Versus Wavelength (Visible Range) of
          Indulin-C and Lime-Treated Kraft Decker Waste              36
13      Weight Average Molecular Weight (M^ Distribution of
          Fractionated Color Bodies from Kraft Decker Effluent
          from IPCO (My. Values at 0)2=0)                              38
lU      Weight Average Molecular Weight (M^) of Acid-Insoluble
          Color Bodies from Decker Effluent Versus Percentage
          of Removal by Massive Lime                                 39

15      Infrared Spectra of Untreated and Lime-Treated Color
          Bodies from Kraft Decker Effluent from IPCO, Indulin-C
          (Salt Form) and Indulin-A (Acid Form)                      U3
                                   vi

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16      Infrared Spectra of Untreated and Lime-Treated Acid-
          Insoluble Color Bodies from Kraft Decker Effluent
          from IPCO                                                 1»5

17      Infrared Spectra of Untreated and Lime-Treated Acid-
          Soluble Color Bodies  from Kraft Decker Effluent
          from IPCO                                                 U8

18      Pyrolysis Gas Chromatograms of Untreated and Lime-
          Treated Decker Effluent from IPCO Compared with
          Indulin-C                                                 50

19      Absorptivity Versus Wavelength (Ultraviolet Range) of
          Indulin-C and Untreated Kraft Bleach Caustic Extract       55

20      Absorptivity Versus Wavelength (Ultraviolet Range) of
          Indulin-C and lime-Treated Kraft Bleach Caustic Extract    56

21      Absorptivity Versus Wavelength (Visible Region)  of
          Indulin-C  and Untreated Kraft Bleach Caustic  Extract      57

22      Absorptivity Versus Wavelength (Visible Region)  of
          Indulin-C and Lime-Treated Kraft Bleach Caustic Extract    58

23      Weight Average Molecular Weight (M^) Distribution of
          Fractionated Color Bodies from Kraft Bleach Caustic
          Extract from IPCO (M  at u>2=0)                            60
2k      Weight Average Molecular Weight (l^)  of Acid- Insoluble
          Color Bodies from Caustic Extract Versus Percentage
          of Removal by Massive Lime                                 6l

25      Infrared Spectra of Untreated and Lime-Treated Color
          Bodies from Kraft Bleach Caustic Extract                   65

26      Infrared Spectra of Untreated and Lime-Treated Acid-
          Insoluble Color Bodies from Kraft Bleach Caustic           67
          Extract

27      Infrared Spectra of Untreated and Lime-Treated Acid-
          Soluble Color Bodies from Kraft Bleach Caustic  Extract      69

28      Pyrolysis GLC of Untreated and Lime-Treated Kraft
          Bleach Caustic Extract                                     71

29      Pyrolysis GLC of Untreated and Lime-Treated Acid-
          Insoluble Fractions "A" from Kraft Bleach Caustic
          Extract                                                    72

30      Pyrolysis GLC of Untreated and Lime-Treated Acid-
          Insoluble Fractions "C-H" from Kraft Bleach Caustic
          Extract                                                    73

                                   vli

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31      Pyrolysis GLC of Untreated and Lime-Treated Acid-Soluble
          Fractions "I" from Kraft Bleach Caustic Extract            7!*

32      Pyrolysis GLC of Untreated and Lime-Treated Acid-Soluble
          Fractions "II+III+IV" from Kraft Bleach Caustic Extract    75

33      Absorptivity Versus Wavelength (Ultraviolet Range) of
          Indulin-C and Untreated Kraft Decker Wastes from CONGO     89
3l*      Absorptivity Versus Wavelength (Ultraviolet Range) of
          Indulin-C and Lime-Treated Kraft Decker Wastes from
          CONGO                                                      90

35      Absorptivity Versus Wavelength (Visible Range) of
          Indulin-C and Untreated Kraft Decker Wastes from
          CONGO                                                      91

36      Absorptivity Versus Wavelength (Visible Region) of
          Indulin-C and Untreated Kraft Decker Wastes from
          CONGO                                                      92

37      Weight Average Molecular Weight (Mj Distribution of
          Fractionated Color Bodies from Kraft Decker Effluent
          from CONGO (t\j at U2=0)                                    91*
38      Weight Average Molecular Weight (\) of Acid-Insoluble
          Color Bodies from Kraft Decker Effluent Versus
          Percentage of Removal by Stoichiometric Lime               95

39      Infrared Spectra of Untreated and Lime-Treated Color
          Bodies from Kraft Decker Effluent from CONGO               98

1*0      Infrared Spectra of Untreated and Lime-Treated Acid-
          Insoluble Color Bodies from Kraft Decker Effluent
          from CONGO                                                 99

1*1      Infrared Spectra of Untreated and Lime-Treated Acid-
          Soluble Color Bodies from Kraft Decker Effluent
          from CONGO                                                101

1*2      Pyrolysis Gas Chromatograms of Untreated and Lime-
          Treated Decker Effluents from CONGO                       103

1*3      Absorptivity Versus Wavelength (Ultraviolet Range) of
          Indulin-C and Untreated NSSC ;;aste from CONGO             107

1*1*      Absorptivity Versus Wavelength (Ultraviolet Range) of
          Indulin-C and Lime-Treated NSSC Waste from CONGO          108

1*5      Absorptivity Versus Wavelength (Visible Region) of
          Indulin-C, and Untreated NSSC Waste from CONGO             109


                                   viii

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U6      Absorptivity Versus Wavelength (Visible Region)  of
          Indulin-C and Lime-Treated NSSC Waste from CONGO          110
U7      Weight Average Molecular Weight (M^)  Distribution of
          Fractionated Color Bodies from NSSC Effluent  from
          CONGO (Mw at W2=0)                                        112
U8      Infrared Spectra of Untreated and Lime-Treated Color
          Bodies from NSSC Effluent from CONGO                      Il6

U9      Infrared Spectra of Untreated and Lime-Treated Acid-
          Insoluble Fractions from NSSC Effluent from CONGO         118

50      Infrared Spectra of Untreated and Lime-Treated Acid-
          Soluble Color Bodies from NSSC Effluent from CONGO        120

51      Pyrolysis Gas Chromatograms of Untreated and Lime-
          Treated NSSC Effluents from CONGO                         123

52      Treatment of Kraft Decker Wastes from Bivalent Ions         129

53      Treatment of Kraft Caustic Extract with Bivalent Ions       130

5^      Treatment of Kraft Decker Waste vith Trivalent Ions         131

55      Treatment of Kraft Caustic Extract with Trivalent Ions      131

56      Effect of FeCls Concentration on. Color Removal.
          Lime Concentration was Kept Constant.  (Color Removal
          Values at 150 ppm PeCl3 from Table UO Have Also Been
          Plotted Here)                                             139

57      Effect of BaCl2 Concentration on Color Removal.  Lime
          Concentration was Kept Constant.  (Color Removal
          Values at 300 ppm BaCl2 from Table UO Have Also
          Been Plotted Here)

58      Effect of Lime Concentration on Color Removal.  Metal
          Ion Concentration Kept Constant

59      Effect of Ferric Chloride and Lime on Sludge Volume

60      The Interactive Behavior of Lime and Metal Ions on
          Color Removal

6l      Percentage of Color Removal by Lime in the Presence of
          Metal Ions

62      Diagram of Gel Permeation Chromatography Apparatus
                                   ix

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                                  TABLES


 No.                                                                  Page

  1      Chemical Data on Effluents Before Shipment from IPCO         13

  2      Sedimentation Coefficients of the Color Bodies               lit

  3      Chemical Data on Freeze-Dried Wastes  from IPCO               16

  1|      Emission Spectroscopic Analysis of Freeze-Dried
           Wastes from IPCO                                            17

  5      Change  in Metal/TOC Ratio During Lime Treatment of
           Mill  Wastes from  IPCO                                      18

  6      Absorptivity  Values Obtained from Visible Spectrum
           at pH 7.6 of Wastes  from IPCO                              19

  7      Absorptivity  Values Obtained from Ultraviolet Spectrum
           at pH 7.6 df Wastes  from IPCO                              20

  8      Effect  of Lime Treatment  on Wastes from IPCO                 26

  9      Change  in Solids Isolated from IPCO Effluents Due  to
           Massive Lime Treatment                                      29

 10      Fractionation of Decker Acid-Insoluble  Color Bodies
           by Column Chromatography                                   30

 11      Fractionation of Decker Acid-Soluble  Color Bodies
           by Sorption on XAD-8 Resin                                 32

 12      Analytical Data  on  Fractions of Decker  Effluent
           from  IPCO                                                   l+i

 13      Indulin-C Pyrolysis Products                                  1+9

lU      Change  in Solids Isolated  from IPCO Effluents  Due
          to Massive Lime Treatment                                   52

15      Fractionation of Acid-Insoluble  Color Bodies  from
          Bleach Caustic Extract by  Column  Chromatography             53

16      Fractionation of Acid-Soluble  Color Bodies  from
          Bleach Caustic Extract by Sorption on XAD-8 Resin           5!*

17      Analytical Data  on Fractions of Kraft Bleach  Caustic
          Extract from IPCO                                           62

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18      Chemical Data on Effluents Before Shipment from CONGO        79

19      Sedimentation Coefficients of NSSC Color Bodies              80

20      Chemical Data on Freeze-Dried Wastes from Continental
          Can Company (CONGO)                                        82

21      Emission Spectrographic Analysis of Freeze-Dried
          Wastes from CONGO                                          83

22      Change in Metal/TOC Ratio During Lime Treatment of
          Mill Wastes from CONGO                                     8U

23      Effect of Lime Treatment on Wastes from CONGO                85

2k      Change in Solids Isolated from CONGO Effluents Due
          to Stoichiometric Lime Treatment                           86

25      Fractionation of Decker Acid-Insoluble Color Bodies
          by Column Chromatography                                   87

26      Fractionation of Decker Acid-Soluble Color Bodies
          by Sorption on XAD-8 Resin                                 88

27      Analytical Data on Fractions of Decker Effluent
          from CONGO                                                 96

28      Change in Solids Isolated from CONGO Effluents Due
          to Stoichiometric Lime Treatment                       '   101*

29      Fractionation of NSSC Acid-Insoluble Color Bodies
          "by Column Chromatography                                  105

30      Fractionation of NSSC Acid-Soluble Color  Bodies by
          Column Chromatography                                     106

31      Analytical Data on Fractions from NSSC Effluent
          from CONCO

32      Treatment of Kraft Effluents with Bivalent Ions             127

33      Treatment of Kraft Effluents with Trivalent Ions            128

3U      Percent Color Removal  from Mill Wastes by the
          Metal Ion-Lime System                                     134

35      Percent Color Removal  from Mill Wastes by the
          Metal Ion-Lime System                                     135

36      Effect of Ferric Chloride Concentration  on Lime
          Treatment of Kraft Bleach Effluents  (Caustic Stage)       137
                                    xi

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37      Effect of Barium Chloride Concentration on Lime Treatment
          of Kraft Bleach Effluents (Caustic Stage)                 138

38      Effect of Lime Concentration on Color Removal with
          Constant Levels of Metal Ions                             138

39      Lime Treatment of Kraft Bleach Caustic Extract in the
          Presence of Metal Ion

^0      Percent Color Removal "by Lime in the Presence of
          Metal Ions

^1      Effect of Varying Lime and Metal Ion Concentration
          on Color Removal (Regression Equation)

U2      Comparison of Regression Coefficients
                                  xii

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                             ACKNOWLEDGMENTS

The support of the President of The Institute of Paper Chemistry,  Mr.
John G. Strange, is acknowledged with sincere thanks.   Dr.  John W.
Swanson, Director of the Division of Natural Materials and Systems of
the Institute, was the Project Director.   Dr. Robert M.  Leekley, Group
Coordinator, Division of Natural Materials and Systems of the Institute
was the coordinator.  Dr. Hardev S. Dugal, Research Associate of the
Institute, was project leader and carried out the work himself and guided
the work for others on this project.  Portions of the  experimental work
were conducted by Messrs. Norman Colson,  John Carlson, Lowell Sell,
Donald Gilbert, John Rademacher, LeRoy Borchardt, and  Dr. Marion A.
Buchanan, each of whom contributed to the work in the  area of his  spec-
ialty.  Dr. Dwight B. Easty and Mr. Edgar Dickey contributed through
valuable suggestion and consultation.  Special thanks  are given to Dr.
Donald C. Johnson who interpreted a huge  number of IR  spectra and  to
Mr. John Church for statistical analysis.

Mr. J. E. Humphrey, Project Director, International Paper Company,
Springhill, La., and Mr. Edgar L. Spruill, Supervisor, Environmental
Control, Continental Can Company, Hodge,  La. and their staff collected
the effluent samples and supplied the necessary information about  their
lime treatment processes.

The partial support of the project by the Office of Research and Develop-
ment, Environmental Protection Agency and the help provided by ex-
project officers, Mr. George R. Webster and Dr. James  D.  Gallup, and
Mr. Ralph Scott, Project Officer, is acknowledged with sincere thanks.
                                  xiii

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                               SECTION I

                               CONCLUSIONS

 1.   No  appreciable  changes  occurred in the color bodies during ship-
     ment  of mill  effluents  from their sources to Appleton, Wisconsin.

 2.   A correlation exists between the absorbance and the color with
     concentration of color  bodies.

 3.   Color bodies  could be stored in the freeze-dried form for longer
     periods without any appreciable changes.

 k.   Color bodies  of all effluents  could be acidified to give acid-
     insoluble  and acid-soluble components.

 5.   When  the "untreated" effluents are acidified, more of the kraft
     waste color is  found in the acid-insoluble rather than the acid-
     soluble component.  However, in the case  of NSSC effluent the
     opposite is demonstrated.

 6.   When  the "lime-treated" effluents are acidified, the kraft Decker
     and NSSC effluents give more color in the acid-insoluble component
     whereas caustic extract gives  more in the acid-soluble component.

 7.   All acid-insoluble components  are of higher molecular weight  (My)
     than  acid-solubles.

 8.   Generally, acid-solubles contain higher carboxylate content than
     acid-insolubles and are more open in structure,

 9-   Color-to-carbon ratio  is generally higher in  acid-insolubles  than
     acid  solubles.

10.   In  the case of kraft Decker and caustic extract more  of  the acid-
     insoluble  color bodies  are removed by  lime, where  in  the case of
     NSSC  effluent more acid-solubles are removed.

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11.  Kraft Decker effluents contain higher methoxyl, and phenolic-
     hydroxyl content than the caustic extract.  However, the NSSC
     effluents contain the highest concentration of these groups.

12.  Color bodies which are not removed by massive or stoichiometric
     lime treatment seem to have the same characteristics.

13.  Color bodies which are not removed by lime generally have low M^
     less ligninlike character, higher carboxylate to aromatic ring
     ratio and lower color to TOG ratio.

Ik.  The upper removal limit of M^ changes from effluent to effluent.

15.  Color bodies not removed by lime have an upper M^ limit from
     200-500.

16.  Addition of certain polyvalent metal ions with lime seems to
     greatly improve the effectiveness of the lime treatment process.
     These metal ions should be added to untreated or lime-treated
     effluents before lime addition.

17•  The metal ions and lime together are more effective color remov-
     ing agents than either of these alone.

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                               SECTION  II

                             RECOMMENDATIONS

1.   Further work is needed to determine the structural  differences of
    the color bodies in order to explain differences  in response to
    lime treatment of different effluents.  This would  lead to a bet-
    ter understanding of the advantages and weaknesses  of the existing
    lime-treatment process and could point the way  to improved means
    of removing color bodies.

2.   Pilot-scale study of a metal ion-lime system should "be carried out
    on mill effluents in order to confirm the laboratory findings, and
    to establish the cost of the treatment involved,

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                               SECTION III

                              INTRODUCTION

Approximately 90 percent of the United States'  chemical wood pulp  is
produced by the kraft pulping process.  In the  kraft or sulfate  process,
"black liquor (the spent cooking liquor) is evaporated and the strong
liquor is burned to recover cooking chemicals.   However, evaporation
of dilute wash liquors is uneconomical, and these traditionally  have
been discharged to streams.  It is a common practice to keep wastes
in the holding ponds to reduce stream pollution.   In spite of various
measures taken to reduce pollution, kraft mill  effluents discharged into
streams are objectionable in color, and further improvements are
needed to reduce the color of these effluents.

The nature of color bodies in kraft mill effluents apparently has  not
been fully investigated.  Presumably, two wastes are believed to be the
main sources of color in the effluents; weak black liquor and effluent
from the caustic extraction stages in the bleach plant.  In addition,
some color may form in the holding ponds.  The  black liquor contains
degraded thiolignins, degraded carbohydrates, and small amounts  of
fatty and resin acids and other extraneous materials.  The degraded thio-
lignins are highly colored and may be an important factor in the color
of mill effluents.  The bleach plant effluents  contain lignins,  which
have been degraded further by chlorination and  oxidation, and smaller
amounts of other materials.  These lignins also are highly colored.

Since lignin is highly resistant to microbiological degradation, the
color passes through the biological treatment processes.  The colored
effluents make the receiving waters brownish in color and reduce the
light penetration in water.  This reduction in  light intensity affects
aquatic plants by reducing photosynthesis and thereby adversely  affects
the dissolved oxygen content of water.

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 LIME TREATMENT PROCESS IN GENERAL

 The lime-treatment process, developed by the National Council of the
 Pulp and Paper Industry for Mr and Stream Improvement (NCASl) is re-
 ported to be  capable of removing 85-95 percent of the color from both
 bleaching and pulping effluents1 **.  This process has gone through the
 pilot-plant stage and at present is being used by several mills
5-7
Three demonstration grants were approved by EPA (formerly FWPCA) to
determine the feasibility of lime precipitation of color bodies from
mill effluents on larger scales.  One of the grants, made to the Inter-
national Paper Company at Springhill, Louisiana, involved massive lime
treatment of bleach plant effluent and brown stock washer effluent
(decker) both separately and in combination.  The other two grants in-
volved stoichiometric lime treatment of total mill effluents at the
Interstate Paper Corporation, Riceboro, Georgia, and at the Continental
Can Company at Hodge, Louisiana.

Although the technology of lime treatment was well developed, conflict-
ing results had been reported with respect to the underlying chemistry
of the process.  However, recent studies by Dence et_ al_. 8 have shown
that the removal of colored material from spent caustic extraction liquor
with' lime is a chemical rather than a physical process and that color
removal is dependent on (a) 'the presence of enolic and phenolic hydroxyl
groups and (b) on the molecular weight of solids contained in the liquor.
No data on molecular weight distribution were reported.

More recent studies done by Dugal et_ al.9 on kraft Decker effluents from
the Interstate Paper Corporation have shown that the color bodies which
are not removed by lime treatment have an apparent weight average molec-
ular weight of less than UOO.  These color bodies were shown to contain
conjugated carboxyl groups, some ligninlike character and were associated
with colorless carbon compounds.

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THE PROJECT AND REPORT

The present project has teen  divided into two parts.  The first part  (or
Phase l) of the project has been concerned with the chemical and physical
characterization of the color bodies in the mill effluents both before
and after lime treatment.  Effluents from two different mills were
studied.

Section IV of this report  deals  vith the study of effluents from the
International Paper Company  (IPCO)  mill at Springhill, Louisiana which
used the massive lime-treatment  process.  Section V describes the study
of the effluent from  the  Continental Can Company (CONGO) mill at Hodge,
Louisiana, which uses the  stoichiometric lime-treatment process.

The second part (or Phase  II) of the project has been concerned with
the lime treatment of mill effluents in the presence of multivalent
ions.  The objective  of Phase II was to establish conditions for an
improved lime-treatment process  using small amounts of multi-valent ions
of other metals in addition  to lime.  This part of the project is  de-
scribed in Section VI.  The  manner  in which the report is organized
is shown in Figure 1.
  Lime Treatment
                                   Processes
                                       I
               I
              Massive
      (international Paper Co.)
             Section IV
       I	
   Kraft Decker
     Effluent
        I	
Untreated
 Lime
Treated
          	1
           Kraft Bleach
           Caustic Extract
                 I
Untreated
  I
 Lime
Treated
                                        Lime Treatment
                                        With Metal Ions
                                          Section VI
                                       Stoichiometric
                                     (Continental Can Co.)
                                         Section V
                                             I
1
Kraft Decker
Effluent
i
reated Lime
Treated
NSSC-
Effluent
1
l i
Untreated Lime
Treated
            Figure 1.   Classification of contents of the  report

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SAMPLING AND HANDLING OF SAMPLES

Composite samples of untreated and lime-treated effluents  (containing
color bodies that are not removed by lime) were shipped by air from
their respective mills to Appleton, Wisconsin.   The samples were  ship-
ped in five-gallon polyethylene jugs enclosed in especially designed
wooden crates provided by The Institute of Paper Chemistry.  The  usual
transit time was two to three days.  Previous work9 had indicated that
the color changed upon storage in liquid form,  therefore,  samples in
transit longer than three days were discarded.

A number of samples (including the duplicate ones) were obtained  from
the mills.  Only eight were processed and fractionated according  to
the program shown in Figure 2 and the rest were investigated in a pre-
liminary way.  These eight samples included the decker and caustic
extract effluents before and after massive lime treatment, and decker
and NSSC effluents before and after stoichiometric lime treatment.  The
lime-treated effluents which were investigated in detail were obtained
from the clarifier before the carbonation stage.   Carbonation of  these
samples was carried out under controlled laboratory conditions.  The
reason for selecting the lime-treated samples "before" carbonation was
that samples carbonated by the mill's stack gases showed an increase in
color' and TOG values and, therefore, for fear of contamination these
were not used for the study.  Depending upon the color to  TOG ratios
and their place in the eluate series of a fractionation run, some
fractions were combined to give larger fractions before analysis.

-------
                             Dilute  Effluent
   Acid-Insoluble

      4
    Alkalization
      I
   Fracti onati on
(Bio-Gel P-2, P-60)


       I
    Freeze-Dry
                               Concentrate
                                   I
                               Carbonation
                                   I
                             Centrifugation



                                   J/
                               Freeze-Dry


                                   V

                              Acidification
      I
Acid-Soluble

      i
Fractionation

(XAD-8 Resin)
      i
Alkalization
      I
 Freeze-Dry
    Figure 2.   Flow diagram for effluent processing and fractionation

-------
                               SECTION IV

                         MASSIVE LIME TREATMENT
             (international Paper Company,  Springhill,  La.)

COLLECTION AND PROCESSING OF EFFLUENT SAMPLES

Source £f Effluent

International Paper Company's (IPCO)  plant  at Springhill,  Louisiana  is
a 1600 ton per day sulfate bleached pulp and paper mill.   The mill uses
debarked softwood and hardwood chips  for pulping.   A small percentage
of sawdust is also used.

Mill wastes for the massive lime treatment  included effluents from the
caustic and the unbleached decker stages or a combination  of the two.
Only a portion of the total effluent  (about 25 percent) was  treated.
This company uses Houghton's antifoaming agent, De Airex 557» for con-
trolling foam problems.

Massive Lime Process at. IPCO

The lime treatment system handled 530 gpm of waste and 63 tons  of lime
(CaO) per day.  Lime dosage ranged from 18,000 to 20,000 ppm.  The
waste and slaked lime were mixed in a 8 x 7 ft reaction tank.  The  de-
veloped floe was allowed to settle in a 26 x 27 ft effluent  clarifier.
The sludge, containing color bodies,  hydrated lime, and fiber,  was
pumped at 20 percent solids to a 10 x 15 ft lime mud storage tank and
after causticizing was burned in a kiln to obtain lime.

The decolorized and clarified effluent that overflowed from the clari-
fier was treated with 650 cfm carbon dioxide to a pH of 10.5-11.0 in a
30 x 2U ft carbonator.  The sludge containing 30 percent solids was
sent to the lime kiln and the clear effluent was sent to the impounding
basin.
                                   11

-------
Color bodies removed from the massive lime process with the sludge  are
to a large extent soluble in sodium hydroxide.   Most of the color com-
pounds dissolve in the white liquor as it is produced in the causti-
izing process.  "White" liquor thus produced with this process  is dark
in color. Color compounds which remain with lime and are not dissolved
in "white" liquor end up in the lime kiln and are burned.   Color bodies
dissolved in "white" liquor eventually are burned in the mill's chemical
recovery furnace.

Variations in the effluent composition did occur because of the fluc-
tuations in the ratios of different kinds of wood used for pulping.
Color of the ef'luent from the caustic stage ranged from IT»000 to
30,000 APHA units.  Details of the Massive Lime Treatment Pilot Plant
can be obtained from the EPA report10 based on work done at the IPCO's
plant at Springhill, Louisiana.

Effect of Shipment

Four batches of samples, each batch containing the untreated, lime-
treated before carbonation and lime-treated after carbonation wastes
were received from Springhill, La. over a period of three months.
The batches of samples contained effluents from the decker washing
stage (referred to as decker), the caustic extraction stage (referred
to as caustic), and mixtures containing 75 percent decker-25 percent
caustic and 50 percent decker-50 percent caustic.

Chemical analyses on these effluents (before shipment) was supplied by
IPCO and are given in Table 1.  (Please note the sample code employed as
shown in Table 1 footnotes.)  Upon receipt at the Institute, representa-
tive aliquots of some of the liquid wastes were chemically analyzed and
compared with the data of Table 1.  The results showed a decrease in
color and TOC during shipment.  The data fluctuated so much that no
definite numbers could be assigned.  However, the percentage of color
removed, based on data obtained before and after shipment, was  almost
the same, indicating that the change in color values during shipment is
constant and whether this change is real or experimental could not  be
established.
                                   12

-------
                                          Table 1.  CHEMICAL DATA OH EFFLUENTS BEFORE SHIPMENT FROM IPCO
U>
ICO? Decker
ppm UD3 LTBC8 LTAC8
pH value 10.1 12.1 11.7
Total solids 2250 3070 1330
Asha 1260 1700 690
Volatile solids* 990 1370 61*0
Calcium as Ga 15 50^ 67
Chlorides as Cl 50 Uo 35
Color units0 890 2UO 270
Total carbon 260 190 230
Inorganic carbon 20 10 10
TOC 2«*0 113d 156d
COD 65U U22 U62
BOD 192 276 252
75? Decker, 25%
UDC7
10.5
2598
1352
12U5
27
339
5100
1*75
50
U25
1U37
2»*6
LTBC7
13.2
3232
2U95
737
k66
339
215
150
20
130
«U
165
Caustic
LTAC7
12.6
31*95
2595
900
K>1*
339
350
160
20
lUO
371
201
50? Decker, 50?
UDC9
9-8
3950
2170
1780
36
835
10,500
1200
100
1100
2002
252
LTBC9
12.3
i*oUo
2760
1280
536
7U5
700
280
50
230
1*78
138
Caustic
LTAC9
10.7
27l»0
1710
1030
252
72»»
1000
U60
1*0
U20
516
130

UC10
9-3
5350
2960
2390
38
986
17 ,000
1^75
150
1325
1527
192
100? Caustic
LTBC10
12.0
1*1*90
3200
1290
552
956
675
270
10
260
563
168

LTAC10
10.5
1*350
2770
1580
21*0
986
780
1*30
150
280
572
132
*Ashed at 600°C for 1 hour.
Calculated by difference.
jIAPHA-color, Pt-Co units.
Calculated figures based on information from IPCO.
UD = Untreated decker effluent.
UC = Untreated caustic effluent.
UDC = Untreated effluent containing UD and
LTBC = Lime-treated before carbonation.
LTAC = Line-treated after carbonation.


UC.










































TOC = Total Organic £arbon.
COD = Chemical Ojcygen Demand.
BOD = Biochemical Oxygen Demand.
IPCO = International Paper Company, Springhill, Louisiana.
7,8,9,10 = Batch numbers of the respective effluent samples.

-------
Table 1 shows that parameters generally increase with increasing amounts
of caustic waste.  BOD values appear to be an exception in that  they
fluctuate but show a downward trend.  The results show that caustic  ex-
tract is about 20 times more colored than the decker effluent.   The  data
further indicate that the color and TOG of lime-treated samples  increase
after carbonation.

Effect of Freeze Drying and Storage

The liquid samples were first concentrated to one-tenth their volume,
carbonated to a pH of 10.2, centrifuged until clear and freeze-dried
(see Figure 2).  Freeze-dried material was readily soluble in water.
Freeze drying of the colored wastes was found to prevent appreciable
changes in color bodies during storage.

The effect of freeze drying on color bodies was determined by observing
changes in the sedimentation coefficient values of the color bodies  be-
fore and after freeze drying.  The sedimentation coefficient is  defined
as the velocity of sedimenting molecule per unit field and is a function
of the anhydrous molecular weight of the sedimenting substance and the
partial specific volume of the solute.  It decreases with the decrease
in molecular weight and increase in the hydration of the sedimenting
molecule.

The sedimentation coefficients were determined according to the method
described by Schachman11 using the ultracentrifuge.  The lapse time
between the measurements of samples before and after freeze drying was
U-5 days.  Results are given in Table 2.
        Table 2.  SEDIMENTATION COEFFICIENTS OF THE COLOR BODIES

                                                               3.
                                  Sedimentation coefficients, S
                                      Before            After
            Effluent               freeze-drying     freeze-drying

         Untreated decker               1.2                1.2
         Untreated caustic              2.0                2>1*

         aS  =  Svedberg = 1  * 10~13.

-------
                                             Table 3.  CHEMICAL DATA ON FEEEZE-DRIED WASTES FROM IPCO
1002 Decker

Yield, o.d. g/100 ml
Asha, %
>,
Volatile , %
Sul fated asha, %
Sodium, %
Calcium, %
Chloride, %
Sulfate, %
Sulfide, %
TOC, %
UD8
0.12
81.5
18.5
93.8
26.8
<0.10
6.3
3U. 6

-------
                           Table 1».   EMISSION  SPECTROSCOPIC AHALYSIS OF FREEZE-DRIED WASTES FROM  IPCO
                                                      (All values on o.d. ash)
Metals, %
Aluminum
Boron
Calcium
Copper
Magnesium
Manganese
Silicon
Sodium
Total*
100% Decker
UD8
O.li30
0.016
0.066
0.0016
0.027
0.0032
0.070
31.0
0.61U
LTBC8
0.071*
0.0081*
0.093
0.0005
<0.020
<0.001
<0.050
31*. o
0.21*7
LTAC8
0.200
0.0085
0.098
0.0005
<0.020
<0.001
<0.050
33-2
0.378
75* Decker. 25* Caustic
UDC7
0.2l»0
0.0068
0.800
0.0008
0.050
0.0081*
0.052
36.7
1.158
LTBC7
0.053
0.0038
0.038
0.0005
<0.020
<0.001
<0.050
33.6
0.166
LTAC7
0.200
0.0058
O.OU6
o.oooU
<0.020
<0.001
<0.050
32.6
0.323
50 f Decker, 50? Caustic
UDC9
0.110

-------
Because no significant changes were noticed in the sedimentation coef-
ficients of color bodies on freeze drying and no appreciable color change
was noticed on storage in the freeze-dried state, all color bodies were,
therefore, freeze-dried and stored until used for further study.

INITIAL CHARACTERIZATION OF COLOR BODIES FROM THE KRAFT
DECKER AND KRAFT BLEACH CAUSTIC EXTRACT EFFLUENTS FROM IPCO

Chemical Characterization

Chemical analysis of the freeze dried wastes is given in Table 3.  The
results are tabulated according to the increasing amount of caustic ex-
tract in the effluent and not according to the batch number.  A compar-
ison of all untreated samples shows that as the amount of caustic extract
increases the volatile and chloride contents increase whereas ash and
sulfate decrease.  No particular trend is noticeable in the case of
sodium and calcium (calcium was removed by carbonation of mill effluents
in our laboratory during processing).  The sulfate and chloride removal
by lime decreases with increasing amounts of caustic extract.

The ash was analyzed by emission spectroscopy and the results are given
in Table k.  The reason for this analysis was to determine whether or
not enough metals are present in the system which could form colored
complexes with the color bodies.  The total amounts of metals in these
wastes were very small.  Sodium values by the emission spectroscopy
method are not as accurate as by the flame photometry method (Table 3)
and are not included in the total.  Surprisingly enough, no determinable
amounts of iron were found in these wastes.  The data in Table  U show
that with the increasing amounts of caustic extract in mill effluent,
silicon and magnesium increase whereas aluminum and boron decrease.
Copper content does not show any definite trend.  The data  further show
that more than 50 percent of the total metals are removed during the
lime treatment.  However, the ratio of metal  content to TOC does not
change much indicating  that these may be associated with the organic
carbon in the effluents  (Table  5).
                                    17

-------
           Table 5.  CHANGE IN METAL/TOG RATIO DURING LIME TREATMENT
                            OF MILL WASTES FROM IPCO
                                        Ratio, metal content/TOC
           Effluent                 Untreated          Lime treated8-

           100% Decker                O.OU                0.05
           15% Decker, 25% caustic    0.05                O.Olt
           50# Decker, 50$ caustic    0.02                0.03
           100# Caustic               0.02                0.03
           All values "based on o.d. total solids.
           aLime treated before carbonation effluent.
            (Carbonation was carried out in laboratory under
            controlled conditions.)

Spectrophotometric Examination

The freeze-dried untreated and lime-treated decker, caustic extract and
mixed effluents vere dissolved in distilled water to give desired con-
centrations.  Visible and ultraviolet spectra of these aqueous solutions
were determined at two pH levels.  In one case the pH was "unadjusted"
and ranged from 9-10.5.  In the other case it was adjusted with a buffer
solution to 7.6.  Distilled water was used as a reference for all of
the samples.  Absorbance values of all samples at pH 7«6 were lower than
their respective unadjusted samples.

In order to have a reasonable comparative picture, absorptivities at pH
7.6 were calculated from these spectra at different wavelengths by di-
viding the absorbance values with the volatile solid concentration in
g/1.  The results are given in Tables 6 and 7 and are plotted in
Figures 3, !*, 5, and 6, and compared with those for Indulin-C.  Values
for LTBC wastes are used.  LTAC values fluctuated, probably because of
the contaminated stack carbon dioxide which was used for carbonation
at the mill site.
                                   18

-------
                                     Table 6.  ABSORPTIVITY* VALUES OBTAMED FROM VISIBLE SPECTRUC AT pH 7.6 OF HASTES FRCM IPCO
VO
100* Decker

Total solid*, g/1
Volatile solids*. %
Volatile solids, g/1
Wavelength, tm
600
580
570
560
550
5kO
530
520
510
500
1*90
1.80
1.70
1.65
160
k55
150
k20
liOO
380
UD8
0.1.
18.5
0.071.

0.16
0.17
0.19
0.22
0.2k
0.27
0.28
0.30
0.35
O.kl
O.k3
0.50
0.50
0.61
0.62
0.66
0.72
1.10
1.5k
2.1.8
LTBC8
1.0
8.5
0.085

0.09
0.11
0.11
0.13
0.15
0.16
0.16
0.18
0.20
0.20
0.23
0.25
0.28
0.29
0.29
0.31
0.3k
0.53
0.85
1.86
L7AC8
1.0
10.5
0.105

0.10
0.10
0.10
O.Ik
0.15
0.16
0.16
0.16
O.I?
0.23
0.2k
0.25
0.28
0.29
0.29
0.32
0.35
0.5k
0.8k
1.7k
75? Decker, 25* Caustic
UDC7
O.k
27.2
0.1088

0.35
0.1.3
0.1.8
0.5k
0.59
0.68
0.75
0.8k
O.?k
1.03
1.16
1.30
1.1.6
1.5k
1.6k
1.73
1.63
2.70
3.k9
k.75
LT3C7
1.0
8.1
0.081

0.0k
0.05
O.O5
0.06
0.07
0.09
0.09
0.09
O.Ik
0.15
0.16
0.16
0.17
0.20
0.22
0.23
0.25
O.k5
0.66
1.32
LTACT
1.0
9-7
0.097

O.03
0.05
0.05
0.06
0.08
0.09
0.09
0.09
0.12
0.13
0.15
0.15
0.18
0.18
0.20
0.22
0.2k
O.38
0.56
1.08
50? Decker. 5Ot Caustic
UDC9
O.k
30.9
0.1236

0.1.2
0.53
0.59
0.68
0.75
0.85
0.9k
1.07
1.13
1.35
1.50
1.69
1.90
2.02
2.13
2.27
2.39
3.kl
k.38
5.78
-LTBC9
1.0
10.2
0.102

0.11
0.11
O.Ik
0.16
0.18
0.18
0.20
0.22
O.25
0.30
0.3k
0.37
0.1.1
O.k3
O.k6
O.k9
0.50
0-.75
1.05
1.66
LTAC9
1.0
9-1
0.091

0.13
0.15
0.16
0.17
0.18
0.20
0.20
0.20
0.23
0.28
0.29
0.33
0.35
0.38
0.39
0.39
O.kk
. 0.65
1.01
2.03
UC10
O.k
37.8
0.1512

0.53
0.68
0.76
0.85
0.9k
1.06
1.17
1.30
l.k6
l.kk
1.80
2.00
2.25
2.37
2.V8
2.6k
2.78
3.87
k.90
6.30
100* Caustic
LTBC10
1.0
8.2
O.O62

0.15
0.15
0.15
0.17
0.19
0.21
0.22
0.23
0.27
0.32
0.35
O.kl
O.k5
O.k9
0.50
0.53
0.55
0.79
1.08
1.73
LTAC10
1.0
9.5
0.095

0.07
0.09
O.09
0.11
0.12
0.15
0.17
0.18
0.22
0.27
0.31
0.36
O.k2
O.k5
O.VT
0.52
0.56
0.89
1.2k
1.92
Indulia-C
0.175
k6.2
0.061

O.6l
0.65
O.70
0.75
0.82
0.91
1.01
1.10
1.19
1.27
I.k3
1.60
1.79
1-90
2.00
2.11
2.25
3-39
k.68
6.9k
       *l/(g)Cas),  obtained b/ dividing absorbance  values with volatile solids In g/1.
        Bued on  total  solids.
        For ssaple  code see Table 1.

-------
                           Table  7.   ABSORPTIVITY   VALUES  OBTAINED FROM ULTRAVIOLET SPECTRUM  AT pH 7.6 OF WASTES  FROM IPCO
100? Decker

Total solids, g/1
Volatile solids*. J!
Volatile solids, g/1
Wavelength, run
3ltO
320
300
295
290
265
282
280
276
275
270
265
260
255
250
2UO
235
230
225
220
215
205
202
200
UD8
0.2
18.2
0.037

5.57
6.98
8.65
9.1*9
10. u5
11.92
12.U7
12.70
12.89
13.19
13.1*9
13.67
1U.22
15.13
16. 1*3
21.38
2U.1.6
27.00
29-90
33.38
38.69
55. i1*

—
LTBC8
0.5
6.5
0.01*25

U. 77
U.82
5.00
5.1*8
5.95
6.60
7.22
7.3k
7.1*8
7.83
8.11
6.33
8.73
9-55
10.16
12.09
13.68
15.55
17.81
20.78
2U.17
37-16

—
LTAC8
0.5
10.5
0.0525

I(.U2
it.Uli
It. 71
5-09
5-70
6.50
6.Q7
7.11
7.19
7.58
7-78
7.96
8.29
8. 92
9."*7
11.53
13.26
15.07
17.28
19.81
23.3li
35-37

—
TT'S De
UUC7
0.02
27-2
0.005U

7. Pit
9.U
13.15
13.69
11*. 99
16.66
17. Ul
17.59
17.77
18.33
10. U
19-63
20.00
20.18
21.66
26.U8
30.37
33.33
38.38
l»1.6T
1*6.66
58.13

—
cker, ?5£
LT3J7
0.5
8.1
0.01*05

2.89
3.W
1*.20
U.69
5.36
6.17
6.6Q
6.86
7.11
7.><3
7.78
7.87
7.98
8.07
8.32
9.26
10.20
11.31
12. 91*
15.16
16.00
26.1*2
_ _
—
Caustic
LTAC7
0.5
9-7
0.0<*85

2.6U
3-09
3-73
lt.01
It.fiO
5-32
5-75
5.98
6.01*
6.3"
6.61*
6.76
6.66
7-01
7-21
8.ll»
9-03
10.02
11.U9
13. U6
15-98
23.62
_
—
so£ Decker, 50«
UDDJ
0.02
30.9
0.0062

10.17
12.26
15.50
16.62
18.23
19.68
20.33
20.81
21.1U
21.78
23-07
23.56
21*. OU
2!*. 36
25- «»9
29-36
32.1*2
37-92
39-52
1*3.39
U7.60
SU.86
.w
—
LTDC9
o.u
10.2
o.o'ioa

3.51
It. 66
6.05
6.86
7-72
8.87
9.1*1
9-78
10.07
10.1*9
10.93
11.08
11.10
11.10
11.12
11.89
12.99
lit. 22
16.08
18,58
21.61
28.06
30.«*7
32.08
Caustic
LVAC9
0.5
9.1
0.0lt55

It. 66
6.20
8.00
8.90
10. 01*
11.1*3
12.28
12.55
12.95
13.58
lit. 13
1"*.33
lfc.35
lit. 06
lit. 19
15. lit
16.36
17.89
20.16
22.90
26.79
35-06
37.32
39.9U
100' Caustic
UC10
0.02
37.8
0.0076

10.26
11.97
15.26
16.32
17-63
18.82
19- ^7
20.00
20.13
?0.76
21.98
22.52
23.03
23.55
2>*.35
28.16
30.79
33.82
37.37
lil. 19
U5-00
U8.U2
U8.69
U8.69
LTBC10
0.5
8.2
O.O1*!

3.76
5.10
7-13
7.93
9-20
10.59
11.1*5
11.76
12.16
12.72
13.26
13-ltO
13.25
12.93
12.78
13-Ult
11*. 56
16.13
18.51
18. 1.6
25."»5
31.50
33-10
3U.5"4
LTAC10
0.5
9.5
0.01*75

1*.OU
5.66
7.6U
8.59
9.77
11.16
11.96
12.36
12. 71*
13.35
lii.no
lit. 19
it*. 08
13.77
13.68
lit. 37
IS-'tg
17.03
19.30
22-Uo
26.29
33-03
35-15
36.69
Indulin-C
0.018
1*6.2
0.008

16.6
2i:6
27.6
30.6
33-5
37.0
38.0
38. U
38.8
38.8
36.6
38. U
39.0
U0.9
Ul*.6
60.5
71.1
80.3
88.9
98.6
llU.l
161.1
169.0
169.6
*l/(g) (CB). obtained by dividing absorbance values with volatile solids in g/1.
bBased on total solids.
 For sample code see Table 1.

-------
o
a)
.0
     7-0
     6.0 _
        380
                                                                   Untreated Wastes



                                                             O  1002 decker



                                                             D  75% decker, 25? caustic



                                                             A  50? decker, 50% caustic



                                                             X  100? caustic
kko
                                       520
560
580
                                     kQQ       500

                                    Wavelength, nm


Figure 3.  Absorptivity values at pH 7.6 of untreated wastes from IPCO (visible region)
600

-------
        6.0
ro
     o
     0)
        5.0
        i*.o
        3-0
        2.0
          I >




          (1
1.0
                    X
                    O
                    D
                            Indulin-C
                              8
                          I
                       I     I
                                                                 Lime-Treated Wastes


                                                             O  100 Jg decker


                                                             D  75 £ decker, 253?  caustic



                                                             A  50# decker, 50JS  caustic


                                                             X  100% caustic
                                                           §6l6ftaflft«
                    400
                     U20
UUO
520
560
580
                               1*60      1+80       500

                                      Wavelength, nm


Figure 1*.  Absorptivity values of pH 1.6 of lime-treated wastes from IPCO (visible region)
600

-------
   170



   160



   150
   130



   120
g  110


bO

H"  100
•H


•H

•P
o
CO
90



80



70



60




50



1*0



30



20



10
        8
                                           Untreated Wastes


                                         O 100$ decker


                                         D 75# decker, 25#  caustic


                                         A 502 decker, 50$  caustic


                                                caustic
     200       220        240      260       280      300

                                    Wavelength, nm
                                                           320
Figure  $•   Absorptivity  valxies at pH J.6 of untreated wastes from IPCO (UV region)
                                        23

-------
•H
-P
O
(0
                           Indulin-C
                                               Lime-Treated Wastes

                                             O 100JK decker

                                             Q 75# decker, 25$ caustic

                                             ^ 50% decker, 5Q% caustic

                                             X 100JS caustic
                     »    t    I
                                                               »    .    t
     200
220
260       2~BO300320
 Wavelength, na
        Figure 6.  Absorptivity values  at  pH 1.6 of nassiye lime-treated
                          wastes  from IPCO (UV region)
                                       21*

-------
The following is observed:

Visible Region (Figures 3 and U) —

     a.  All samples exhibit increased absoptivity as  the wave-
         length decreases.
     b.  None of the samples contain a maximum in this region.
     c.  Untreated samples  containing higher percentages  of
         caustic extract give higher absorptivity values, with
         100 percent caustic having the highest, even  higher than
         Indulin-C (Figure  3).
     d.  Lime-treated samples exhibit similar but lover absorp-
         tivities than their respective untreated samples (Figure h).

The visible spectra demonstrated that no single color  is  present in the
waste samples, rather they are mixtures of different colors as  character-
ized by the increase in absorptivity as the wavelength decreases.  In
addition, it was demonstrated that lime treatment decreases the amount
of color-giving materials.

Ultraviolet Region (Figures 5 and 6) —

     a.  The samples exhibit increased absorptivities  as the
         wavelength decreases.
     b.  Untreated samples from the decker stage have  lowest
         absorptivity values compared to others (Figure 5)•
     c.  Lime-treated samples exhibit similar but lower absorptivities
         than their respective untreated samples  (Figure 6).
     d.  All samples show a "shoulder" at about 280 nm.  A similar
         "shoulder" was noticed at 205 nm in some cases.  These
         absorptivity curves are quite similar to the one exhibited
         by Indulin-C.
     e.  Generally, samples containing higher percentages of untreated
         caustic extract gave higher absorptivity values with a shift
         in the absorptivity  "shoulder" from 280 nm to 265 nm.   The
         reason for this shift is not understood.  Chlorinated lignins
         may have something to do with this.  Hardwood lignins are

                                   25

-------
         known to have maxima (shoulder) at shorter wavelengths
         than softwood lignins, about 275 instead of 280 run12.
         Goring13 has cited 272 nm as the position for the maximum
         for birch lignin.

The ultraviolet spectra indicated that the mill wastes contain materials
similar to those present in lignin and that the amount of these materials
is decreased by lime treatment.

Effect of Lime Treatment

The percentage of color and TOC removal and percentage decrease in absorp-
tivity were calculated from data in Tables 1,6, and 7 and the results
are given in Table 8 and plotted in Figures 7 and 8.

         Table 8.  EFFECT OF LIME TBEATMENT ON WASTES FROM IPCO
Composition of
mill effluent
Caustic,
%
0
25
50
100
Decker,
%
100
75
50
0
Color
removal ,
%
73.0
95.8
93.3
96.2
TOC
removal a,
%
53.0
69.14
79. U
80.3
Decrease in
absorptivity , %
at 1*20 nm at
5fc.6
83.3
78.0
79.6
280 nm
1*2.2
6l.O
53.0
U2.5
et
"Based on values for effluent samples.
 Decrease in absorptivity caused by lime treatment based on volatile
 solids content of solids isolated from effluents.

The data show that 7U to 96 percent of color and 53 to 80 percent of TOC
are removed during lime treatment.  The effectiveness of lime generally
increases with increasing amounts of caustic extract in mill effluent
(Figure 7) •   The decrease in absorptivity ranged from 51* to 83 percent
at 1*20 nm and 42-61 percent at 280 nm (Figure 8).

In order to understand the changes due to lime treatment and to avoid
the problems of mixed systems, only decker and caustic extract effluents

                                   26

-------
as such were used for further study.  Mixed effluents containing 50-50
or 75-25 percent decker and caustic effluents were not investigated in
detail.
                                                   Color
              0
             100
25          50
75          50
   Effluent Composition
100$ caustic
   I decker
            Figure 7.  Color and total organic carbon removal of
                     wastes from IPCO by lime treatment
FURTHER CHARACTERIZATION OF COLOR BODIES FROM KRAFT
DECKER EFFLUENT FROM IPCO

Fractionation of_ Color Bodies.

Acidification -
From previous experience9 it was known that most of the colored material
could be precipitated by acidification of the strong aqueous solutions
of the color bodies from kraft decker wastes.  Thus, when 15 percent
solutions of the freeze-dried untreated and lime-treated decker wastes
were adjusted to a pH of 1.0 with approximately 3N hydrochloric acid,

                                   27

-------
    100 _
                                                            nm
                                                             nm
        0          25          50                     100#  caustic
        100        75          50                       o%  decker
                     Effluent Composition
      Figure 8.   Decrease in  absorptivity  of wastes  from
                     IPCO by  lime treatment
much gaseous material vas evolved, and a dark colored precipitate was
obtained.  During acidification an odor similar to that of hydrogen
sulfide was also detected.  However, the major part of gases is believed
to be due to the presence of carbonates in the parent sample. Thus, acid-
ification was used to isolate the acid-insoluble and acid-soluble color
bodies.  The results of this fractionation are given in Table 9.

The data in Table 9 show that upon acidification of untreated wastes,
82.5 percent color and 51.0 percent TOC were recovered in the acid-
insoluble fraction.  The acid-soluble fraction contained 17-5 percent
color and 1+9.0 percent of the TOC.  However, when lime treated wastes
were acidified, the acid-insoluble fraction contained only 51.0 percent
color (13.8 out of 27.0) and 7.0 percent TOC (3.3 out of 1*7-0),  The
acid-soluble fraction of the lime treated waste contained 1*9-0 percent
                                   28

-------
color (13.2 out of 27.0) and 93.0 percent TOO (U3.7 out of U7.0).   Table
9 further shows that the lime treatment removed 83.3 percent color and
93.5 percent TOO from the acid-insoluble color bodies and only 2k.5 per-
cent color and 10.8 percent TOC from the acid-soluble color bodies.
These values were calculated from the yield data of the untreated  and
lime-treated color bodies.

        Table 9.  CHANGE IK SOLIDS ISOLATED FROM IPCO EFFLUENTS
                     DUE TO MASSIVE LIME TREATMENT
Untreated
decker waste



Fractions
Decker waste
Acid-insoluble
Acid-soluble

Colora
yield,
%
100
82.5
17-5
.
TOC
yield,
%
100
51.0
1*9-0
Lime-treated
decker waste
Color
yield,
%
27-0
13.8
13.2
TOC
yield,
*
1*7.0
3.3
1*3.7
Reduction
due
to limec
Color,
*
73.0
83.3
21*. 5
TOC,
%
53.0
93.5
10.8
Yield values basis untreated decker solids.

*APHA units, Pt-Co color.
 Total organic carbon.

Column Chromat ography —
The acid-insoluble color bodies were dissolved in distilled water and
fractionated on Bio Gel P-2 column (200-cm long and 2.5 cm in diameter)
having an exclusion limit of molecular weight 2600.  The first fraction
"A" from each run was further fractionated on Bio Gel P-60 column (100
cm long, 2.5 cm diameter) having an exclusion limit of molecular weight
60,000.  The details of fractionation are given in the experimental part
of this report.  All fractions obtained from the gel columns were ana-
lyzed for color, TOC, and absorbance at U20 nm and 280 nm.  The data
were used for calculating percentages of yield and percentage of removal
by lime in each fraction.  Only data on color and TOC are given in Table
10.  (For details see Appendix I.)
                                   29

-------
         Table 10.  FRACTIONATION OF DECKER ACID-INSOLUBLE COLOR
                     BODIES BY COLUMN CHROMATOGRAPHY
Untreated
acid-insoluble
color "bodies
Color TOC
yield, yield,
Fractions % %
Lime- treated
acid-insoluble
color "bodies
Color TOC
yield, yield,
% %
Re ducti on due
to lime0
Color, TOC,
% %
Fraction "A" from
P-2 through P-60
column
  A2 through A6a

Acid-insoluble color
bodies through P-2
column

      A
      B
      C
  D through R

Un fractionated
acid-insoluble
color bodies
12.9
te.l
 6.2
15.7
                                          3.6
                                          1.0
                                                   0.1*1
                                                   0.11
72.1
97-6
93.1*
99-3
55-0
 2.U
 2.1
23-0
82.5
21.9
 1.7
 2.1
25-3
51-0
                                          U.6
                                          1.0
                                          1.1
                                          6.1
                                         13.8
                                                   0.52
                                                   0.18
                                                   0.2U
                                                   2.U
                                                   3.3
91.6
58.3
U7-5
73.5
97-6
89.1*
88.6
90.5
83.3    93.5
Percentages of yield are calculated on the basis of untreated original
waste.
Calculated by difference so that values for A =
                                                     + A2 through
 Calculated by difference so that values for un fractionated acid-insol-
 uble color bodies =(A+B+C+D through R).
 Values calculated from "yield" data of the solids isolated from untreated
 and lime-treated effluents.
The results show that in the case of untreated acid-insolubles approxi-

mately 67 percent of the color (55.0 out of 82.5) and U3 percent TOC

(21.9 out of 51.0) were obtained in fraction "A," whereas in the case

of lime-treated acid-insolubles this fraction contained only 33 percent

of the color and 15*7 percent of TOC.  Average color and TOC removed by

lime were 83-3 and 93.5 percent, respectively.


The untreated and lime-treated acid-soluble color bodies were isolated

into four fractions by first sorbing on Rohm & Haas Company's Amberlite
                                   30

-------
XAD-8 resin (polystyrene cross-linked with divinyl  benzene)  and then
deserting with aqueous ethanol (1:1 mixture of water and 95  percent
               t
ethanol).  It should be kept in mind that  the  fractionation  was not
sharp, and thus each fraction could contain some  material  similar to
that found in the previous fraction.   The  ethanol was  removed  under re-
duced pressure and each fraction was made  alkaline  with  sodium hydroxide
to pH about 9-0,

The first fraction contained material which passed  unadsorbed  through
the column.

The second fraction contained material which was  held on the column
initially, but was readily eluted from the column with water.  Upon
alkalization this fraction deepened in color and was more  highly  colored
than the first fraction.

The third fraction was an intermediate fraction  and was  collected until
the eluate was neutral to Congo red.

The fourth fraction contained material eluted with  aqueous ethanol.

All fractions obtained from the XAD-8 column were analyzed as  before  and
the results are given in Table 11.  The results  show that  in that  case
of untreated acid-solubles approximately 62 percent color (10.9 out  of
17.5) and 33 percent TOG  (l6 out of U9-0)  were obtained in fraction  IV.
(Some color and TOG is unaccounted for), whereas in the case of lime-
treated acid-solubles this fraction contained TO percent color and 30
percent TOG.  The average color and TOG removed by  lime were 2^.5 and
10.8 percent, respectively.  The table further shows that practically
no color and TOG are removed by lime from acid-soluble Fractions  III
and IV  (when calculated on the combined basis).

Characterization of Decker Effluent Fractions
Fractions of acid-insoluble and acid-soluble color bodies of the untreat-
ed wastes were obtained by column chromatography.  Several of these
fractions were very small, especially after allowing for amounts required
for molecular weight determinations.

                                   31

-------
      Table 11.  FRACTIONATION OF DECKER ACID-SOLUBLE COLOR BODIES
                       BY SORPTION ON XAD-8 RESIN
                         Untreated
                        acid-soluble
                        color bodies
Lime-treated
acid-soluble
color bodies
Reduction due
Fractions
(Combined III + IV)
IV
III
II
I
Unfractionated acid-
soluble color bodies
Color
yield,
%
(12.1)
10.9
1.2
2,5
0.9
17-5
TOG
yield,
%
(19-0)
16.0
3.0
16.2
7.6
Up.O
Color
yield,
%
(12.0)
9.2
2.8
1.3
0.5
13.2
TOC
yield,
%
(20.1)
12.9
7.2
ll*.7
fc.9
^3.7
to limea
Color,
%
(1.0)
15.5
+
W.O
1*1*.5
21*. 5
TOC,
%
(+5.0)
19-5
+
9.2
35.5
10.8
Percentages of yield are calculated on the basis of untreated organic
waste.  "+" Values showed an increase.
Values calculated from "yield" data of the solids isolated from un-
 treated and lime-treated effluents.

To provide sufficient material for chemical analysis some adjacent frac-
tions were combined to give bullcy fractions.  Thus, Fractions "Ai"
through "A6" were combined (referred to as "A"), "C" through "B" were
combined, and out of the four acid-soluble fractions the adjacent frac-
tions which were similar with respect to their ratios of color to organic
carbon were combined to give two larger fractions.

Visible and Ultraviolet Spectra —
Visible and ultraviolet spectra of Indulin-C, acid-insoluble fractions,
and acid-soluble fractions of the untreated and lime-treated wastes were
determined at pH 7.6.

Absorptivity values from these spectra were calculated at definite wave-
lengths and the results are plotted in Figures 9. 10, 11, and 12.
                                   32

-------
                                   Untreated Waste Fractions

                                  O  A

                                  D  C-R

                                  A  I+II  1
                                  X  in+iv/
                                  V
                                     Acid-
                                     insoluble

                                     Acid-
                                     soluble
200
220
320
                            260      280      300
                              Wavelength,  am
Figure 9«  Absorptivity versus wavelength  (ultraviolet  range) of  Indulin-C
               and untreated kraft decker  waste from IPCO
                                  33

-------
200
                               Line-Treated Waste
                                    Fractions
                                   O   A

                                   D   C-R
                                   X   IIX+ZV
220
21*0
300
320
340
                              260      280
                              Wavelength, no
Figure 10.  Absorptivity versus wavelength (ultraviolet range) of Indulin-C
              and lime-treated kraft decker waste from IPCO
                                  31*

-------
 a
 o
 to
•rl
-P
O
01
                                                                    Untreated Waste
                                                                        Fractions
                                                                                 Acid-
                                                                                 insoluble
                                                      U80
                                          500
520
51*0
560
580
600
Tigare 11.
                                                     Wavelength, nm

                                  Absorpti-rity versus vavelength (visible range)  of Indulin-C  and
                                         untreated kraft decker waste from IPCO

-------
7-qir
                                                        Lime-Treated
                                                      Waste Fractions
                                                  U80      500
                                                Wavelength, nm
                 Figure 12.  Absorptivity versus wavelength (visible region) of Indulin-C and
                                       line-treated kraft decker waste
600

-------
Ultraviolet region (Figures  9 and 10)  - All samples  exhibited  an increase
in absorptivity as the wavelength decreased.   Indulin-C,  untreated "A"
fraction, untreated III and IV fraction and lime-treated  III and IV
fractions showed an Indulinlike characteristic absorption band at 280 nm
indicating the presence of more ligninlike  materials.   The  lime-treated
color bodies of the acid-insolubles  (Fractions "A"  and C-R) showed lower
absorptivity values than their respective untreated fractions.  However,
the acid-soluble color bodies (Fractions I  + II and III + IV)  showed an
increase in absorptivity after lime-treatment (compare Figures 9 and 10).

Visible region (Figures 11 and 12) — All samples gave  simple absorption
curves and exhibited an increase in  absorptivity as  the wavelength  de-
creased.

Acid-insoluble color bodies (Fractions A and C-R) showed  lower absorp-
tivities after lime-treatment while  the absorptivities of acid-soluble
color bodies (Fractions I -t- II and III + IV) increased or remained un-
changed after lime treatment.

At this stage it can be said that almost all fractions contain lignin-
like color bodies.  The differences  in absorptivity may be  due to
different levels of degradation of color bodies.

Molecular Weight Distribution —
Molecular weights of some selected fractions of acid-insoluble and all
acid-soluble components of the untreated and lime-treated color bodies
were determined by the sedimentation equilibrium method using the
analytical ultracentrifuge11*.  In the present work the "short  column
sedimentation equilibrium method" was used.  Details of this  method are
given in the Experimental part.  The apparent "Weight Average" molecular
weights  (My) for each fraction were calculated at zero angular velocity
(to2 = 0) because the My were changing with change in w2.   The results
are plotted in Figures 13a and b.                        .

Figure 13a shows that untreated acid-insoluble components are much higher
in My than those of lime-treated acid-insolubles.  The My values drop

                                   37

-------
o
H
     36
     32
    28
    2k-
    20
16
    12
                Acid-insolubles

                 Untreated

                     Lime Treated
         ?-.<-r>
                                                Acid-solubles

                                                    -Untreated
                                                        -Lime Treated
                                           IV  III  II   I
                                          Eluate Fractions
                                         (XAD-8 Fractionation)
        A3   A5   B   D    F
       i   A*  .Ac    C   E
                                               t  i
                                   H    KM    P
                                     J    L    N
                      tluate Fractions
                (Gel permeation  chromatography)

 Figure 13.  Weight average molecular weight (My) distribution of
        fractionated color bodies from kraft decker effluent
                   from  IPCO  (MV values at t,)2=0)
                                 38

-------
sharply from 33,000 to about 300 and then rise slightly near Fraction
"J."  The increase, however, is not very significant and may be due  to
different ash contents of the fractions.  The noticeable point of inter-
est is that most of the higher M  material has been removed by lime.
My of untreated and lime-treated acid-soluble color bodies are quite
similar to each other (Figure 13b).  Lime-treated materials (M^ range
< 350) have, however, lower M^ than untreated materials (range < 950).

Figure lU shows that acid- insoluble color bodies having an apparent M^
of less than 200 are not removed by the massive lime treatment.  The
intermediate range of My. 200 to 2000 apparently undergoes partial removal
and over 2000 are completely removed.  However, over 80 percent removal
occurs above a M^ of 200-500.  The average color and TOG removal of the
acid- in soluble fraction was found to be 83-3 and 93.5 percent, respec-
tively (Table 10 ).
        100
         80
         60
         1*0
      w
         20
              g
              tsi
1-8
                  Partial
                  Removal
                    Zone
                                 Complete
                                 Removal
                                   Zone
            0
500       1000     1500     2000
  M, acid-insoluble color bodies
                                              2500
           Figure  lU.   Weight  average  molecular weight  (M^)  of
            acid-insoluble  color bodies  from decker effluent
              versus percentage of removal by massive lime
                                    39

-------
The acid soluble color bodies behave differently.  In this case color
bodies which were sorbed on XAD-8 resin and later desorbed by aqueous
ethanol (Fractions III + IV) were practically untouched by lime, while
21 percent removal occurred in the case of color bodies which could not
be sorbed on XAD-8 resin.  The average color and TOO removal of the acid-
soluble fractions was only 2U.5 and 10.8 percent, respectively.

Ghemi cal_ _Charact eri z at ion —
The results of the chemical analysis are given in Table 12.   Fractions
were analyzed for ash, phenolic hydroxyl, total sugars, and methoxyl
content.  Absorptivities (absorbance/volatile solids in g/liter) at U20
nm (Ei»2o), as a measure of original color, and at 280 nm (E^eo) as  a
measure of lignin content have also been tabulated.   Actually two values
may be used as approximate measure of lignin content, namely E2eo and
methoxyl.   Calculated ratios of Ei^o/E^o, E^SS/ESOO, Ei^o/MeO, and
E2eo/MeO have also been included in Table 12.

The data in Table 12 suggest:
     a.   The untreated decker waste contains 0.25 meq phenolic
         hydroxyl per gram of volatile solids,  whereas the lime-
         treated waste contains  0.07 meq./g volatile  solids,  about
         73 percent reduction.
     b.   Total sugar content is  reduced from l6.Ul g/100 g volatile
         solids  to 6.0 g by lime-treatment.   A reduction of 63. U per-
         cent.   (For individual  sugars  see Appendix  II.)
     c.  Msthoxyl content of decker waste is reduced from 6.hk to
         3.18 percent  by lime  treatment (50.5 percent).   Acid-
        soluble fractions  "l  +  II" contain the lowest amount of
        MeO indicating least  ligninlike character.
     d.  Ratios, Ei»20/MeO,  E2eo/MeO,  and Ei^o/Eaao indicate  that
        except  for some greater loss  in methoxyl, lignins  in the
        untreated waste are very similar to the lignins in  Indulin-
        C.   The lignins in the  lime-treated waste appear to be more
        degraded.

-------
                                     Table 12.
ANALYTICAL DATA OH FRACTIONS OF DiiCKER EFFLUENT FROM IPCO
          (Basis o.d. volatile solids)
Untreated decker

Mol . vt . ran^e

Ash", %
Volatile solidsb, f
Phenolic hydroxyl,
neq/g
d
Total sugars , %
KeU-.cxyl (MeO) , %
En 20
E? 80
En 20 /MeO ratio
E; 10 /MeO ratio
Ei.2o/E2»o ratio
E*65/E600 ratio
Indulin-
C
—

53.80C
146.20

1.32
—
21.05
3-39
38.U
0.16
1.82
0.008
3-11*
Acid-insoluble
Original
100-33,000

81.5
18.5

0.25
16. in
6.14).
1.10
13.05
O.IT
2.03
O.OSlt
3.76
A
3,000-33,000
66 7
38. 5U
6l.li6

—
—
13. 51*
2.95
87. 7»»
0.22
2.0U
0.108
3.18
C-R
170-500
on L
63.86
36.1U

—
—
It.Uo
1.20
10.79
0.27
2.05
0.111
3.11
Acid-soluble
III+IV
600-930
6o.2
31-58
68.1.2

—
—
U.81*
0.92
10.86
0.19
2.2U
0.085
3.00
1+11
100-150
19.1*
90.9li
9.06

—
—
0.89
0.21
2.53
0.2)4
2.8U
0.083
3.6V
Original
150-1 .300

91-5
8.5

0.07
6.00
3.18
0.53
7.86
0.17
2.l»7
0.067
3-13
Lime- treated decker
Acid-insoluble
A
800-1 ,800
33. li
ND
—

—
—
ND
1.U3
6.63
—
—
0.216
2.U»
C-P
150-680
52.2
70.75
29-25

—
—
3.1t2
0.70
7.00
0.20
2.05
0.100
3.5b
Acid-soluble
III+IV
250-330
91.0
38.89
61.11

—
—
U.87
0.85
17.15
0.17
3.52
0.050
3.09
I+II
<170
13.6
79.21*
20.76

—
—
0.58
O.liU
U.19
0.76
7.22
0.105
3.36
aAshed at 600°C  for  1 hour.   Ash  calculated on o.d.  material.
tVolatile solids = 100 minus  5  ash.
"llndulin ash values  higher  than expected.
 for individual  sugars see  Appendex  II.

E2io, E»2o, E<.«s, Esoo are  absorptivities  at 280, U20, U65 and 600 nm wavelengths.

-------
     e.  Ratios of Ei^es/Eeoo were calculated on the baa is of
         observations by Ortiz De Serra et_ al..15.   The authors
         have used ratios of Ei^es/Eees as an indication  of condensed
         (lower ratios) or open (higher ratios) structures of humic
         (acid-insoluble) and fulvic (acid-soluble) acids.  Our
         use of E6oo was mainly due to the reason  that Eees values
         were not available and also that over 580 nm not much
         change in absorptivity was noticed (see Figures 11 and 12).
         The data suggest that except lime-treated acid-insoluble
         fraction "A," all other color bodies had  structures either
         similar to or more open than Indulin-C.

Infrared Spectra —
The effect of lime treatment on the organic material is  difficult to dis-
cern.  A new band appears at 1722 in the lime-treated sample, but spectra
of the fractions from the original lime-treated sample do not contain
such a band nor even a distinct shoulder.  Fractionation concentrates
the lignin-related systems primarily into untreated acid-insoluble  "A"
fraction (and its lime-treated analog).  In this fraction lignin bands
are very prominent compared with carboxylate bands.  There is also  lignin-
related material in the acid-soluble fraction of lower ash content,  but
the carboaylate absorption is much more intense than the absorption  of
the aromatic units.

Comparison of the spectra of untreated and lime-treated acid-insoluble
fractions "A" suggested that the lime-treated fraction has a signifi-
cantly higher ratio of carboxylate groups to lignin systems.

(Lime-treated Fraction C-R may be largely composed of an artifact since
the spectrum contains many unusual features.)

The IR-spectra were run on samples with ash, whereas references are
made to chemical analysis calculated on ash-free basis.

Untreated decker (Figure 15) - Tnis original sample (decker effluent)
has very prominent bands at 625 and llto cm"1, indicating that appreci-
able sulfate is present.  The presence of  carbonate is  also  suggested
                                    1*2

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1»000  3500   3000   2500
2000  1800  1600
     Wave Humber
ll»00 1200  1000 800  600   1*00  200
     Figure 15-  Infrared spectra of untreated and lime-treated  color bodies
           from kraft decker effluent from IPCO,  Indulin-C  (salt form)
                            and Indulin-A (acid form)

-------
by absorption bands at ihhO and 875 cm"1.  The bands at 1600 and the
shoulder near lUOO are consistent with bands expected for carboxylate
salts.

Lignin-related aromatic systems are undoubtedly present to a small ex-
tent.  This view is supported by methoxyl analysis (6.hh percent) and
a weak band at 10^5-  A shoulder at 1505 provides further support for
lignin.  The carboxylate and carbonate bands in this region (ll*00-l650
cm"1) are far more dominant than the aromatic-related band at 1505.

Lime-treated decker (Figure 15) ~~ The lime-treated sample spectrum, al-
though similar in general appearance to untreated, differs in several
ways:  l) the OH/CH ratio is higher (judging from absorbances at 3UOO
and 2920), 2) a new band is evident at 1722, 3) more intense bands are
present at lUUO and 875 probably signifying higher carbonate content,
and U) a new band is seen at 670 cm"'1.

Higher inorganic content is supported by a higher ash content and lower
methoxyl content (3.18 percent) for the lime-treated sample.

The new band at 1722 may be the result of oxidation occurring during
lime-treatment creating carbonyl groups.  The interpretation of this
band and its significance is uncertain since the band does not appear
in any of the subsequent lime-treated fractions.

Untreated acid-insoluble Fraction "A" (Figure 16) — The main differ-
ences resulting from the separation of the acid-soluble material are
that the sulfate and carbonate contents are markedly reduced and the
lignin  bands are much more evident.  The strong bands at 1582 and
about lUOO probably reflect carboxylate salts.  Prominent bands at 1505
and lU60 are evidently due to lignin (aromatic skeletal vibrations), and
this agrees nicely with the high methoxyl content (13.51* percent).  A
band at 1030 is also apparent, which is thought to arise in part from
in-plane aromatic C-H bonding in lignin.  In fact, the bands at 1030,
1135, 1215, and 126U are probably all lignin-related.

-------
                           §
V/l
                           UOOO  3500  3000
2500  2000  1800 1600 lUOO 1200 1000 800
          Wave Number, cm 1
600
                                                                                                 200
                           Figure 16.  Infrared spectra of untreated and lime-treated acid-insoluble
                                       color bodies from kraft decker effluent from IPCO

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Lime-treated acid-insoluble Fraction "A" (Figure 16) — The lime-treated
decker waste yielded this acid-insoluble fraction which has an IR some-
what similar to that of the untreated Traction "A."  However, this
sample seems to have much more sulfate and considerably less lignin.
Carboxylate salt is again apparent (1590 and ikkO cm"1) and a weak "band
at 1505 is probably due to lignin.  Comparison of relative intensities
of the 1590 band with the band at 1505 suggests that the ratio of carbox-
ylate to aromatic rings is higher in the lime-treated than in the un-
treated acid-insoluble "A"-fraction.

Untreated acid-insoluble Fractions "C-R" (Figure 16) — This fraction
contains substantial sulfate in contrast to the higher molecular weight
acid-insoluble Fraction "A."  The ash content is markedly higher (6h
percent vs_. 39 percent), and the methoxyl content is lower (-U.U percent
vs. 13.5^ percent).  The ratio of carboxylate to aromatic rings is appre-
ciably higher in this sample than it is in untreated "A"-fraction (dis-
cussed earlier).

Lime-treated acid-insoluble Fractions "C-R" (Figure 16) — The spectrum
of this acid-insoluble fraction of the lime-treated material has several
distinctive bands which are not apparent in any of the other samples in
the series.  These occur at 1160 (strongest band), 1075 (strong), and
medium bands at 950, 858, 5^5, and 52U cm"1.  Nearly all of these bands
have a well-resolved appearance in contrast to the broad, multicomponent
bands which dominate the other spectra.

Above 1200 cm"1 the spectrum is somewhat more similar to the spectra of
other samples.  There is only a very weak shoulder at 1510, possibly
suggesting low lignin content (3.^ percent methoxyl), but the other
lignin band near lO^tO is not visible at all.  Again, carboxylate salt
is likely since broad absorption is seen at 1565 and 1380 cm"1.  The
sulfate content is thought to be low due to the'limited intensity of
the band at 625.

The differences between this fraction and its untreated counterpart are
so substantial that it is quite probable that this particular fraction
is an artifact.  Differences of this magnitude are not evident in any
                                    1*6

-------
of the other comparisons (in all four series examined under this  proj-
ect) between untreated and lime-treated samples.

Various possibilities were considered to account  for this suspected ar-
tifact but none are very satisfactory.  The spectrum is thought not to
be the result of column breakdown (the column is  a polyacrylamide)  nor
does it seem to reflect the presence of silicates.

Untreated and lime-treated acid-soluble Fractions "I + II" (Figure  If.) —
These acid-soluble fractions show almost identical IR spectra, which are
dominated by sulfate peaks.  The untreated and lime-treated samples have
ash contents of 91 and 79 percent, respectively.   The only indications
of lignin-related substances are the methoxyl content (0.89 and- 0.58 per-
cent ) and the shoulder at 1050 cm 1.

Untreated and lime-treated acid-soluble Fractions "ill + IV" (Figure
IT) ~~ These spectra are also quite closely related.  Sulfate content
appears to be quite low in both samples.  Lignin content appears  to be
comparable  judging from methoxyl contents (U.81* and U.87 percent)  and
from the bands at 1570  (shoulder), 1U60 (shoulder), 1265, 1215, and
10U5.  The region between 11*00 and 1650 is dominated by the carboxylate
bands, with the aromatic ring bands at 1510 and lU60 visible only as
shoulders.  This contrasts sharply with the lignin-rich untreated and
lime-treated Fractions  "A" where the  ratio of carboxylate bands to aro-
matic ring bands was much lower.

The only possible effect of lime treatment on the organic systems pres-
ent may be the inversion of intensities of the lignin-related bands at
101*5, 1265, and 1215.   In the lime-treated sample the band at 10U5 is
of lower intensity than the other two bands  (at 1265 and 1215).

Pyrolys is gas liquid chromatography — The details of the procedure
and conditions are given in the experimental part of this report.

In order to learn more  from the small amounts of  color bodies  available,
pyrolysis gas liquid chromatography  (GLC) was carried  out.  Initially

-------
Oo
                                             lime-Treated 'I+II'
                             1*000   3500   3000   2500   2000  1800  1600 lUOO  1200 1000  800   600   UOO  200
                                                              Wave Number, cm
                                  Figure 17.  Infrared spectra of untreated and lime-treated acid-soluble
                                             color bodies from kraft decker effluent from IPCO

-------
the mass spectrographic identification of the compounds  was  planned but
was not carried out because of lack of time and funds.

Although quantitative analysis of the vapor can be conducted by  accu-
rately measuring the area under a GLC peak, only qualitative analysis
was carried out in the present work.  The chromatograms  are  given in
Figure 18.

The peaks of Indulin-C were identified against known samples16  and then
compared with the decker effluent color bodies.  Results are given in
Table 13.
                Table 13.  INDULIN-C PYROLYSIS PRODUCTS

     Pyrolysis product
          peak no.                 Identified compound

             21                    Guaiacol
             23                    U-Methyl guaiacol (creosol)
             28                    U-Ethyl guaiacol
             29                    U-Propyl guaiacol
             31                    Eugenol guaiacol
             31a                   It-Vinyl guaiacol
             32                    cis-isoeugenol
             3k~}                   trans-isoeugenol
                f Probably
             38)                   Vanillin

Peaks 10, 12, IT, 21 (guaiacol), and 35 which are quite  prominent in
the untreated decker effluent are missing in the lime-treated one.  The
relative ratios of peak heights also seems to have changed during lime-
treatment.  Peaks 3^ and 38 in the untreated and lime-treated chromato-
grams had retention times similar to that of trans-isoeugenol,  and
vanillin, respectively.

-------
           Indulin-C
           Lime-treated decker
                 38      .. 32    28
                                                                 I
                                                                      I
Tide, minW
Temp. , °C  <-
   36    32  28    21*   20   16    12    8    If    0
200	>  187   171  155  139   123   107   91   75
      Figure 18.  Fyrolysis gas chromatograas of untreated and lime-treated
                decker effluent from IPCO compared vith Indulin-C
                                    50

-------
Ferulic and vanillic acids upon pyrolysis had the same retention  timca
as eugenol and guaiacol, respectively,

Figure 18 shows that the untreated and lime-treated decker effluents
gave somewhat similar chromatograras.   A study of such chromatograms
as compared to that of Indulin-C suggest that the color bodies  in
the effluent are degraded lignin fragments.

FURTHER CHARACTERIZATION OF COLOR BODIES FROM
KRAFT BLEACH CAUSTIC EXTRACT FROM IPCO

If the pulp is bleached, additional color bodies are solubilized and
removed from the pulp.  Bleaching at  IPCO was accomplished in multi-
stages with most of the color removed in the "Caustic Extraction Stage."
Effluent from the caustic extraction  stage referred to as "caustic
extract" is almost black.

Fractionation o_f Color Bodies

Acidification -
Acidification was carried out by the same method that was used for the
decker effluent and is described in detail in the Experimental part of
this report.  The results are given in Table lU.  The data show that
when untreated caustic extract waste was acidified approximately 93 per-
cent color and 79 percent TOO were recovered in acid-insoluble fraction.
The acid-soluble fraction contained only 7 percent color and 20 percent
TOG.  However, when lime-treated waste was acidified the acid-insoluble
fraction contained only 37 percent color (1.5 out of ^.0) and lU percent
TOG (2.7 out of 19.6).

The acid-soluble fraction of the lime-treated waste contained about
62.5 percent color and 86 percent TOG.  Table lU further shows that
lime treatment removed 98. U percent color and 96-6 percent TOG of the
acid-insoluble fraction and only 66.7 percent color and 16.8 percent
TOG of the acid-soluble color bodies.

-------
              Table  lU.   CHANGE  IN  SOLIDS  ISOLATED  FROM IPCO
                 EFFLUENTS  DUE  TO  MASSIVE LIME TREATMENT
Untreated
caustic waste



Fractions
Caustic extract
Acid-insoluble
Acid-soluble

Colora
yield,
%
100
92.8
7-2
•u
TOC
yield,
%
100
79-3
20.3
Lime-treated
caustic waste
Color
yield,
%
U.O
1.5
2.5
TOC
yield,
%
19.6
2.7
16.9
Reduction due
to
Color
%
96.0
98.lt
66.7
lime
TOC,
%
80.1*
96.6
16.8
Yield  values "basis untreated caustic extract solids.
fAPHA  units, Pt-Co color.
  Total organic carbon.
 Column  chromat ography —
 Fractionations of acid-insoluble and acid-soluble color bodies of the un-
 treated and lime-treated caustic extract were carried out on Bio Gel P-2,
 P-60 columns and XAD-8  resin, respectively.  The results are given in
 Tables  15 and 16 (for details see Appendix III).

 The results in Table 15 show that in the case of untreated acid-insolu-
 bles approximately 77 percent of color (71.6 out of 92.8) and 70 percent
 TOC (55-7 out of 79-3) were obtained in Fraction "A," whereas after
 lime-treatment this fraction contained only 16 percent (0.2l* out of 1.5)
 of the  lime-treated color and 15 percent TOC.  The average color and
 TOC removed from acid-insolubles by lime were 98,1* and 96.6 percent,
 respectively (over 99 percent of Fractions "A" and MB" were removed).

 Table 16 shows that in the case of untreated acid-solubles approximately
 96 percent color and 6k percent TOC were obtained in Fraction IV,
whereas lime-treated samples had 76 percent color and 1+1 percent TOC
 in Fraction IV.  The average color and TOC removed from acid-solubles
by lime were 67 percent and 17 percent, respectively.

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      Table 15.   FRACTIONATION OF ACID-INSOLUBLE COLOR BODIES FROM
             BLEACH CAUSTIC EXTRACT BY COLUMN CHROMATOGRAPHY
      Fractions
                          Untreated
                        acid-insoluble
                         color bodies
                        Color
                        yield,
          TOC
         yield,
                   Lime-treated
                  acid-insoluble
                   color bodies
Color
yield,
                            TOC
                           yield,
Reduction due
  to lime	
Color,   TOC,
Fraction "A" from P-2
through P-60 column
  Aa through Ae

Acid-insoluble color
bodies through P-2
column

        A
        B
        C
   D through H

Unfractionated acid-
insoluble color bodies
                         2.2
                        69.1*
          2.6
         53.7
 0.08
 0.16
                            0.15
                            0.26
 96. U
 99-8
9U.2
99.5
71.6
13.7
 O.UO
 7-1
92.8
                                 55-7
                                  0.
                                  3.8(
                                 79.3
0.21+
0.12
0.06
1.08
O.Ul
0.33
0.15n
1.1»3C
99.7
99.1
85.0
8U.8
99-3
98.7
82.7
62. U
                   1.5
          2.7
         96.6
Percent yields are calculated on the basis of untreated original vaste.

^Calculated by difference so that A = (Ai + Aa through Ae).
 Calculated by difference so that values for unfractionated acid-insolu-
 ble color bodies = (A + B+C+D through H).
°Total by actual determination.
'Values calculated from "yield" data of the solids isolated from untreated
 and lime-treated effluents.


Characterization of Caustic Extract Fractions from IPCO


To provide sufficient material for chemical analysis some adjacent frac-

tions vere combined to give bulky fractions.  Thus, Fractions "A" through

"A6" were combined giving "A," "C" through "H" were combined, and out of

acid-solubles, Fraction I was used as such and II, III, and IV were com-

bined.
                                   53

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    Table l6.  FRACTIONATION OF ACID-SOLUBLE COLOR BODIES FROM BLEACH
               CAUSTIC EXTRACT BY SORPTION ON XAD-8 RESIN
Untreated
acid-soluble
color "bodies
Fractions
(Combined II+III+IV)
IV
III
II
I
Unfractionated acid-
soluble color bodies
Color
yield,
%
(7.58)
6.9
0.36
0.32
0.27
7.2
TOG
yield,
%
(15-6)
13.2
1.0
l.U
6.6
20.7
Lime- treated
acid-soluble
color bodies'
Color
yield,
%
(2.21)
1.9
0.15
O.l6
O.ll*
2.5
TOG
yield,
%
(9.W)
7.0
0.76
1.7
7.0
16.9
Reduction
to lime
Color,
%
(70.8) (
72.2
58.3
50.0
W.I
66.7
due
a
TOG,
%
39.1*)
1+7-0
2U.O
+
+
16.8
Percent yield are calculated on untreated original waste.   "+"  Values
shoved an increase.
 Values calculated from "yield" data of the solids isolated from un-
 treated and lime-treated effluents.

Visible and UV Spectra —
Visible and UV spectra of all fractions were determined at pH 7-6.   Ab-
sorptivity values were calculated by dividing absorbance with volatile
solids concentration in g/1 and the results are plotted in Figures  19,
20, 21, and 22.

Ultraviolet region (Figures 19 and20) — All samples exhibited an in-
crease in absorptivity as the wavelength decreased and were lower than
Indulin-C.  Almost all untreated and lime-treated samples showed absorp-
tion bands at 280 and 205-210 nm indicating the presence of aromatic
compounds (ligninlike).  The absorptivity values (in UV region) of acid-
insoluble Fractions "A" was reduced, "C-H" was increased and of acid-
soluble fractions (l and II + III + IV) remained almost unchanged by
lime treatment.  Only at wavelengths less than 220 nm, the lime-treated
acid-soluble color bodies had noticeably higher absorptivity values than

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                                  Untreated Yaste
                                     Fractions
                                  O  A
                                  D  C-H
                                  A  i
                                  X  ii+in+iv
I
*t**A§   S8BBBB
                                                     9
              i
               i
200
  220
2l»0
300
320
                                                        31*0
                           260     280
                            Wavelength, nm
Figure 19.  Absorptivity versus vavelength (ultraviolet range) of Indulin-C
               and untreated kraft bleach caustic extract
                                55

-------
                                         Lime-Treated
                                        Waste  Fractions
 200
220
260      280
Wavelength, na
300
320
3UO
Figure 20.   Absorptivity versus vavelength (ultraviolet range) of Indulin-C
              and lime-treated kraft bleach caustic extract

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                          Untreated Waste
                             Fractions
                                                 9   @   d   fi   fi
                    1*80       500
                   Wavelength, nm

Absorptivity versus wavelength (visible region) of Indulin-C
       untreated kraft bleach caustic extract
     580
600
and

-------
VJI
0>
                                                                Lime-Treated
                                                              Waste Fractions
                                                                O  A
                                                                D  C-H
                                                                A  I
                                                                X  ii+iu+iv
                                                                    500
                                                         Wavelength, run
                          Figxore 22.  Absorptivity versus wavelength (visible region) of Indulin-C and
                                            lime-treated kraft bleach caustic extract
580
600

-------
their respective untreated color bodies.   This suggests that  chromophores
which absorb at lower wavelengths, especially below 220 nm,  are removed
to a lesser degree by lime treatment.

Visible region (Figures 21 and 22) — All samples gave simple  absorption
curves and exhibited an increase in absorptivity as the wavelength de-
creased.  Fraction "A" of the untreated acid-insoluble color bodies had
absorptivity equal to or higher than Indulin-C.  Except Fraction C-H all
other fractions showed a decrease in absorptivity after lime  treatment.
A comparison of visible and UV spectra suggests that, although acid-
soluble fractions showed no loss in absorptivity in the UV region after
lime treatment (in fact an increase in absorptivity was noticed below
220 nm), a definite loss of absorptivity in the visible region occurs,
indicating that some color is in fact removed by lime from the acid-
soluble fractions.

Molecular Weight Distribution —
Molecular weights of selected fractions of acid-insoluble and all acid-
soluble components of the untreated and lime-treated color bodies were
determined in a manner similar to that used for the decker effluents.
The results are plotted in Figure 23a and b.

Figure  23a suggests that most of the higher molecular weight material
is removed by lime.  The untreated acid-insoluble color bodies range
from My 100 to 125,000, whereas the acid-solubles range from M^ 100 to
1100.   After lime treatment, however, these values range between < 250
to 9^00 and 100 to U50, respectively.  Acid-soluble color bodies, Frac-
tion I, had the lowest M^ and acid-insoluble  color bodies Fraction "A"
the highest.  The individual My values of acid-insoluble fractions fluc-
tuated  somewhat but still a general decrease  is noticeable from AI to
H.  These fluctuations could be due to different ash contents  of the
fractions.

Figure  2k shows that  acid-insoluble color bodies having an apparent  M^
of less than  UOO  are  not removed by lime treatment.  The intermediate
range of M^ 1+00-9500  apparently undergoes partial  removal.   Over 9500
                                   59

-------
                                  M   2
          Acid-insolubles
            Untreated
                                  o
                                  H
                                  X
Acid-solubles
  • Untreated
           Lime Treated
                                           IV   III   II    I
                                           Eluate Fractions
                                          (XAD-8 Fractionation)
  A!   A3   As   B    D
     A2   Aj,   A6   C   E
         Eluate Fractions
 (Gel permeation chromatography)

Figure 23.  Weight average molecular veight (My) distribution of
       fractionated  color bodies from kraft bleach caustic
                  extract fron IPCO (My at ^=0)

-------
complete removal occurred.   Over 98 percent removal occurs above a M^

of 1000.  The average color and TOG removal of the acid-insoluble

fraction was found to be 98. U and 96.6 percent, respectively (see Table

15).

              .Nonremoval Zone
        lOOi
         80
         60
         1*0
         20
                                 Pkrtial
                                 Removal
                                  Zone
Complete
Removal
 Zone
                  2000      1*000     6000     8000     10,000
                        Mw, .acid-insoluble color bodies
    Figure 2l*.  Weight average molecular weight  (Mj of acid-insoluble
           color bodies from caustic extract versus percentage
                        of removal by massive lime

The acid-soluble color bodies having a M^ of over 500 are removed by

lime.   The average color and TOG removal of the acid-soluble frac-

tions  was found to be 66.7 and 16.8 percent, respectively.


Chemical Characterizations —

The results of the chemical analysis are given in Table 1?.  The data

suggest:

     a.  The untreated caustic extract contains 0.32 meq. .phenolic

         hydroxyls per gram of volatile solids, whereas this

                                   61

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                         Table 17-  ANALYTICAL DATA ON FRACTIONS OF KRAFT BLEACH CAUSTIC EXTRACT FROM IPCO
                                                   (Basis o.d. Volatile Solids)
Untreated caustic extract

Mol. wt. range
Color recovery
Ash8, %
Volatile solids, %
Phenolic hydroxyl
meq/g
Total sugars0, %
to Methoxyl (MeO) , %
El. 20
E260
En 20 /MeO ratio
£2 ig /MeO ratio
E»j»/E2«o ratio
E»«s/E»o« ratio
Indulin-
C
—
—
53.8
1(6.2
1.32
21.05
3.39
38. U
0.16
1.82
0.088
3.1U
Ac id- insoluble
Original
100-125,000
—
62.2
37.8
0.32
1|.60
2. Oil
3.88
19-00
1.90
9-31
0.201*
I*.l*l4
A
2,000-125.000
71.6
23.2
76.8
„
1.90
3-69
20.61
1.914
io.au
0.179
li.lS
C-H
100-1.000
28.lt
86.6U
13. -36
..
0.62
0.91
5-71
1.1»7
6.27
0.159
3.U6
Acid-soluble
II+III+IV
800-1 ,100
96.5
28.69
71.31

1.61
2.23
15-90
1.39
9.88
O.lUO
U.6I*
I
100
3.5
83.65
16.35

0.7U
0.1*0
U.16
0.5l»
5.62
0.096
3.51
Original
100-9 .500
—
91.80
8.20
0.13
3.1*2
1.71
0.79
12.05
0.1.6
7.0U
0.067
3.3U
Lime-treated
caustic extract
Acid-insoluble
A
1.000-9.500
16.0
26.77
73.23

3.06
2.11
13.00
0.69
li.25
0.162
3.87
C-H
100-800
81*. 0
67.97
32.03

3.22
1.92
15.29
0.60
U.75
0.126
3.85
Acid-soluble
II+III+IV
1*00-500
88.5
38.82
61.18

2.71
1.21*
16.1*8
0.1*6
6.08
0.075
3.39
I
100
11.5
88.35
11.65

1.29
0.27
I*. 7U
0.21
3.67
0.057
3-33
.Ashed at 600°C. 1 hour.  Ash calculated on o.d. material.
Volatile solids - 100* ash.
 for individual sugars see Appendix II.

EJ««, E*2«i £*«$> and Esoo &re absorptivities at 260, 1*20, 1*65 and 600 nm wavelengths.

-------
         value  drops  to 0.13 after  lime treatment  (59-3 percent
         reduction).
     b.   Total  sugar  content is  reduced from U.6 to 3-^2 g/100 g
         volatile  solids  (25-5 percent reduction).
     c.   Methoxyl  content  of unfractionated color  bodies (original)
         decreases from 2.0U to  1.71 by lime treatment (l6.2 per-
         cent  reduction).   However, the fractionated  color bodies
         (Fractions A, C-H, II + III + IV and  l) of the lime-
         treated waste have higher  methoxyl per 100 gram volatile
         solids than  the  untreated  waste  indicating a more lignin-
         like  character.   Fractionation probably has  eliminated
         some  carbon  not  associated with  MeO.
     d.   Ratios of E^o/MeO, E280/MeO  and Ei»2o/E280 suggest
         that  the  untreated caustic extract  color  bodies con-
         tain  more chromophores  which  absorb in the visible
         region than  the lime-treated  color bodies.
     e.   Ratios of E465/E6oo  suggest that the  untreated  caustic
         extract and its Fractions  "A" (acid-insoluble), and
         II +  III  + IV (acid-soluble)  are more open  in structure.
         In fact,  all color bodies  have  more  open  structure
         than  Indulin-C.

One noticeable difference between caustic extract  and decker wastes  is
that the lime-treated color fractions  of caustic  extract  contain higher
MeO than their untreated counterparts.

'Infrared Spectra —
Caustic extract has the lowest lignin content  (judged by MeO content
and certain IR-bands) compared to  decker or NSSC wastes.   lime treat-
ment seems to produce a band at 1723 (or else markedly  changes the car-
boxylate content) which may also be present as a shoulder in spectra of
subsequent fractions.

One of the fractions of the untreated caustic extract was found to be
composed of ammonium chloride and  sodium chloride.   Carboxylate bands
                                   63

-------
 in the samples which have higher lignin contents are so strong that the
 aromatic vibrations at 1510 cannot be detected.

 Untreated caustic extract (Figure 25) — Strong bands are evident in the
 OH region (ca. 3^00) and in the region where carboxylate salts commonly
 absorb (l600 and 1380, broad).  The presence of lignin is suggested by
 a weak band at 10^0, but the usual obvious lignin band at 1500 is not
 apparent.  That lignin is a very minor component of the sample is further
 indicated by the methoxyl content of only 2.04 percent.

 There are distinct bands at 830, 765, and TOO cm~: which could be partly
 due to lignin, but this is doubtful since they do not appear in the
 spectra of subsequent fractions.  These bands do appear to show again
 in the lime-treated sample, but there again they are not evident in any
 of the fractions resulting from this material.   It is interesting to
 note that the bands at 830 and 700 are also quite evident in the spectra
 of the untreated and lime-treated decker wastes (Figure 15), but again
no sign of these bands is seen in the spectra of either acid-soluble or
 acid-insoluble fractions.

 Lime-treated caustic extract (Figure 25) — The higher ash content (91.8
 vs. 62.2 percent) of the lime-treated sample is undoubtedly due to greater
 carbonate content and somewhat greater sulfate content.  The carbonate
bands at about lU50 and 890 are quite prominent, although it should
be recognized that the former band is broad and contains a component
 due to carboxylate groups.  The other carboxylate band is seen at about
 1600.  Carbonate bands are not evident in the spectrum of the untreated
 caustic extract so their appearance is a direct result of the lime treat-
ment.  The previously cited bands at 81+0, 780,  and 700 are clearly seen
 in the lime-treated caustic extract.  These latter bands are consider-
 ably more intense here relative to the untreated which parallels the
 increase in ash and decrease in methoxyl contents (1.71 compared to
2.0*0.  This argues against these bands having their origin in lignin.
A broad band at llUO and another band at 625 implicate sulfate as a
probable minor component of the sample.

-------
ON
     O
     §
    •P
    -P
    •a
     co


1*000
1 1
3500 3000
i
2500
i
2000
i
1800
Wave
i
1600
Number,
i
lUOO
cm l
i
1200
I
1000
                    Figure 25-
                                                                                    800
Infrared spectra of untreated and lime-treated color bodies
       from kraft bleach caustic extract
                                                                   1*00
200

-------
Lime treatment has apparently produced a carbonyl group in this fraction
judging from the new band which appears at 1723.  The fractions which
result from this lime-treated sample do not contain such a band, al-
though a shoulder in this region is apparent in spectra of lime-treated
acid-insoluble fraction "C-H" and acid-soluble fraction II + III + IV;
however, such shoulders are also present in spectra of untreated samples.
An alternative interpretation is that the carboxylate absorption masks
the carbonyl band at 1723 in the untreated sample, but lime treatment
causes precipitation of calcium salts rich in carboxylate content.  This
results in a change in the proportions of carboxylate and carbonyl groups,
thus accounting for the different appearance of the spectral region 1550-
1750 cm'1.

Neither of the alternative hypotheses can account, however, for the
absence of a distinct carbonyl band (rather than a shoulder) in all of
the spectra of fractions resulting from the lime-treated caustic extract.
Since there is a definite carbonyl band in the original lime-treated
sample spectrum, why isn't there a carbonyl band in at least one of the
four fractions analyzed?

Untreated acid-insoluble Fraction "A" (Figure 26) - The spectrum of this
acid-insoluble fraction is very similar to that of untreated caustic
extract.   Dominant OH and carboxylate peaks are seen.  The band at about
1380 is less broad than is the case in the untreated caustic extract,
and peaks at 830, 760, and 700 are not seen.  The presence of lignin
is indicated by the methoxyl content (1.9 percent) and a band at about
10UO overlapping an adjacent band.

Lime-treated acid-insoluble Fraction "A" (Figure 26) — Again dominant
hydroxyl (3^20) and carboxylate bands (1570 and 1^*30) are seen, although
the latter are shifted significantly from the corresponding bands in
untreated acid-insoluble Fraction "A" and lime-treated caustic extract.
Carbonate, which was implicated as a component of the original lime-
treated sample, is also seen here (bands at lU30 and 880 cm** ).
                                   66

-------
o
s
•p
•H
§
s
1*000  3500   3000  2500
2000  18OO  16OO ll»00 1200 1000 800 600
    Wave Number, cm"1
200
  Figure 26.   Infrared spectra of untreated and lime-treated acid-insoluble
               color bodies from kraft bleach caustic extract

-------
 One  interesting  feature  of this spectrum is the sharp resolution of the
 OH  stretching bands.  The band components are at 2850, 2925 and a
 shoulder at 2950.  The appearance of this C-H region is like that of
 the  spectra of pure hydrocarbon systems with substantial methyl and
 methylene content.  It is thought that an aliphatic acid salt system (or
 a mixture of such salts) would best explain the observed C-H stretch-
 ing  bands.  In contrast, the C-H band at 2920 for untreated acid-insol-
 uble Fraction "A" is very broad and ill-defined.

 A component of the broad band at 10^0 is probably due to lignin.

 Untreated acid-insoluble Fraction C-H (Figure 26) — This sample is anom-
 alous .   The spectrum shows its main bands to be due to ammonium ion:
 1^00, 2800, 20^0, and 3130.  X-ray diffraction analysis revealed that
 this sample is primarily sodium chloride and also contains ammonium
 chloride.  Ammonia may have been generated during a localized degradation
 (microorganisms?) of the polyacrylamide column; the ammonia in turn could
 have been neutralized by acid groups to form the ammonium salt.  The
 position  of the major bands (listed above) coincides with those observed
 for  known ammonium chloride.   Thus, the infared data very strongly sup-
 port the  conclusion that ammonium salts are present.

 Lime-treated acid-insoluble Fraction "C-H" (Figure 26) — This spectrum
 is very similar to that of the lime-treated Fraction "A" except that
 there is no sign of a carbonate band at 880, and that the maximum at
 1U35 has  shifted in this spectrum to lUOO.  The latter shift probably
 also reflects reduced carbonate content.   The higher frequency carboxyl-
 ate band  is again near 1575 and the C-H stretching region is well-
 resolved.  The broad absorption centered at 10^0 in the lime-treated
 Fraction  "A" now is centered at about 1100, probably indicating higher
 sulfate content.

 Untreated and lime-treated acid-soluble Fractions "I" (Figure 27) -
 These samples give very similar IR spectra.   They are both over 80 per-
 cent in ash content.   The carboxylate bands show at 1600 and IkOO in
both.  Both samples apparently contain sulfate (bands at 1130 and 620

                                   68

-------
ON
3500   3000    2500
2000  1800  1600
     Wave.Huraber, cn~1
                                                                             1200  1000  800
200
                             Figure 27.  Infrared spectra of untreated and line-treated acid-soluole color
                                               bodies from kraft bleach caustic extract

-------
cm'1).  Hie lime-treated contains bands at 1350 and 1190 not clearly
seen in the spectrum of untreated acid-soluble Fraction I.  Their origin
is uncertain.

Untreated and lime-treated acid-soluble Fractions "II + III + IV"
(Figure 27) — These spectra are nearly identical in their appearance.
Broad carboxylate  bands appear at 1580 and 1390 for the untreated and
at 1575 and 1395 for the lime-treated sample.  No sulfate or carbonate
bands are clearly apparent.  The contribution of aromatic rings is only
indicated by broad, weak absorption at 10^0 cm l.

FyrolyBis Gas Liquid Chromatography —
Qualitative pyrolysis-GLC vas run on all acid-insoluble ("A" and "C-H")
and acid-soluble (I and II + III + IV) fractions of the untreated and
lime-treated caustic extract.  The chromatograms are given in Figures
2&-32.  Similar peak numbers were allotted to a fraction before and
after lime treatment.  Therefore, chromatograms in one figure can be
compared with one another with respect to their peak members.  Chro-
matograms of the fractions from the same series (i.e. , untreated or
lime treated) from different figures can only be compared with respect
to their retention times and not by peak numbers.

Chromatograms of the untreated fractions in Figures 28, 29, and 30 are
almost similar to their lime-treated counterparts but are not identical,
indicating that most of the changes occur in these fractions (acid-in-
solubles) by lime treatment.

Chromatograms of the untreated and lime-treated acid-solubles (Figures
31 and 32) are almost identical, indicating a negligible change due to
lime treatment.
                                   70

-------
                                                                (I
Lime-treated caustic extract
Untreated caustic extract
Tine, min
Temp., °C
IF
            36
                   1
   200 —-
Figure 28.
  32    26
	>  187
                              21*
                             171
                                    20
                                   155
 16
139
                                                 JL
             JL
 12
123
 8
107
 k
91
                 Pyrolysis  GLC of  untreated  and lime-treated
                   kraft bleach  caustic extract
 0
75
                             71

-------
   Lime-treated caustic "A1
   Untreated caustic "A1
Time, min
frvawm OT
1
1*1*
/. ,
1 J^
1*0 36
onn
I
32
•~~*r~~*^
I
28
TR7
— V-^
1
21*
1 71
r
20
1 c;=;

16
1 7O
1
12
197
1
8
1O7
1
14
01
J
0
•7
Figure 29.  Pyrolysis GLC of untreated and lime-treated acid-insoluble
            Fractions "A" from^ltraft bleach caustic extract
                               72

-------
Lime-treated caustic "G-H
Untreated caustic "C-H
                               2k    20    16
                               171   155   139
                                                          8     1»     0
                                                         107   91     75
Figure 30.   Pyrolysis OLC of untreated and lime-treated acid-insoluble
           Fractions "C-H" from kraft tleach caustic extract
                              73

-------
 Lime-treated caustic "I"
 (tatreated caustic "I"



Time,
fH» >•>•">



	 • 	

1 1 I
min Uk kQ 36
On / 	 ^ftA
31*

1
32
_i
£



1
•TJS \J V
30
1 I
28 2k
At 1 Tl
^y\
2?*
1
20
ICC
iy

i
16
TSO


1
12
10-S


1
8
inv


1
k
m


|
0
TC
Figure 31.   Pyrolysis GLC of untreated and lime-treated acid-soluble
            Fractions "I" from kraft bleach caustic  extract

-------
          Lime-treated  caustic II+III+IV
           Untreated caustic II+III+IV
                                                                    I
Time, min
Temp., °C
32
 28
187
 21*
171
 20
155
 16
139
 12
123
 8
107
                                            91
 0
75
       Figure 32.  Pyrolysis GLC of untreated and lime-treated acid-soluble Fractions
                       "in-IirHV" frori'iiraft tleach caustic extract
                                        75

-------
                                SECTION V
                      STOICHIOMETRIC LIME TREATMENT
               (Continental Can Company, Hodge, Louisiana)

COLLECTION AND PROCESSING OF EFFLUENT SAMPLES

Source of Effluent

Continental Can Company (CONGO) at Hodge, Louisiana is a kraft and neu-
tral sulfite semichemical (NSSC) pulp and paper mill using 88 percent
softwood and 12 percent hardwood (total capacity 700 t/day).   No multi-
stage "bleaching is used.  About 300 tons of pulp is bleached "by single-
stage hypochlorite every two weeks.  This is expected to have very
little effect on the quality of total effluent17.  The mill uses well
water of low hardness (12-20 ppm).

Mill wastes for the stoichiometric lime treatment included two effluents
from pulping and papermaking stages of kraft and NSSC mill.   Effluent
containing major amounts of wastes from NSSC mill are referred to as
NSSC effluent and the other as decker effluent.   The total mill effluent
volume was 16.5 MOD.  Only a portion of this effluent (about 62 percent)
was treated.  The total mill effluent had a BOD load of 3^,000 Ib per
day and a color of less than 1200 APHA units.

Stoichiometric Lime Process at_ CONGO

The lime-treatment system initially handled about 10 MGD of mill efflu-
ent.  Lime concentration ranged from 1300-1500 ppm.

Lime slurry at about 10 percent consistency is injected in the pipe main
through which raw effluent is pumped to the color clarifier (135 ft diam-
eter) ; no mixing device is employed.  The clarifier overflow is dis-
charged through submerged orifices into an external collecting  channel.
Sludge discharge is through 8-inch draw-off piping.

From the color clarifier the effluent passes to  a 30 x 12 ft carbonation
tank, where lime kiln stack gas is bubbled through the primary  color
                                   77

-------
clarifier waste.   The calcium carbonate formed by carbon  dioxide  reac-
tion with the remaining calcium hydroxide is  settled in a second  clari-
fier substantially identical to the first one.   Sludge  is withdrawn
through a 6-inch pipe.

Fiber losses through the existing mill are 20-25 lb  per ton pulp.  These
fines are allowed to go through the system and seem  to  help in  the set-
tling of lime-color bodies precipitate in the primary clarifier thickener
of the lime-treatment system  . .

Combined sludge,  withdrawn from the color clarifier, is pumped  to a
storage tank.  Dewatering of the sludge is carried out  in a Sharpies
P-5*100 solid-bowl centrifuge operated at 2300 rpm.   The cake  is dis-
charged to the same kiln feed conveyor which  receives the kraft lime
and filter cake.   The concentrate liquor is returned to the color clari-
fier to recover residual solids.

The lime kiln is  a gas  fired unit 12 ft in diameter  and 290 ft  long.
Recovered lime and new lime use are shared impartially  between  causti-
cizing and effluent treatment.

Effect of_ Shipment

Two batches each of decker and NSSC effluents were received from  Hodge,
Louisiana over a period of about five months.  Each  batch contained
separate samples of untreated,  lime-treated before carbonation  and lime-
treated after carbonation stages of the lime  treatment  plant.   All
samples were characterized as follows:

Chemical analyses on these effluents (before shipment)  were supplied by
CONGO and are given in Table 18 (please note the sample code  employed as
shown in Table 18 footnotes).  Aliquots of liquid wastes  were also ana-
lyzed at the Institute upon receipt and the data were compared with
those of CONGO.  The results showed that "after shipment" results gen-
erally were higher for color and lower for TOC.  No  definite  conclu-
sion could be drawn from the results mainly because  this  trend was not
consistent and differed from sample to sample of the same waste.  The
                                   78

-------
Table 18.  CHEMICAL DATA ON EFFLUENTS BEFORE SHIPMENT FROM  COHCO
Batch 1
ppn CCUPP-1 CCLTBC-1
pH value 9.0 12.3
Tot|l solids 975 1103
Ash U91 908
Volatile solids 1.81. 195
Sodium 163 18U
Sulfate 22 't 230
Chloride
Color units0 685 70
70C 202 69
BOD 19!* 135
*Ashed at 600°C for 1 hour.
Calculated by di f f erence.
APHA color, Pt-Co units.
CONGO = Continental Can Company, Hodge,
Decker
CCLTAC-1
10.1.
671*
557
117
193
231
17
76
75
132



La.
Effluent
CCUPP-3
9-1
11*11
557
851*
21.2
325
980
298




CCUPP = Untreated decker effluent including paper machine and
CCU3 = Untreated N3SC including kraft decker, paper machine
CCLTBC = Line- treated before carbonation from CONGO.
CCLTAC = Lim<_— treated after carbonation
TOC = Total Organic Carbon.
BOD . = Biochemical Oxygen Demand.
from COHCO.





Batch 2
CCLTBC- 3
12.1
2033
661.
1369
380
220
179





CCLTAC-3
10.5
1723
1109
1.15
370
17
300
l!*l
282





CCUS-2
8.1
2068
806
1262
299
310
'2000
521
628





Bat ch 1
CCLTBC-2
12.1
2393
1137
1256
331*
301*
820
1.1*7
637




NSSC Effluent
CCLTAC-2
9.8
1797
802
995
322
293
11*
91*0
1*59
633




ccus-4
7.8
1833
867
966
310
180
1750
672
51*5





Batch 2
CCLTBC-1.
12.2
21*0!*
1268
1136
3U5
185
12
390
398
163





CCLTAC— 1*
9.5
1690
6^0
1C 50
160
500
1*16
i*as




pulping area vastes from CONGO.
and pulping wastes from CONGO.

























-------
data obtained at the Institute vere consistent and could be checked with-
in reason at different times.  It was, therefore, concluded that no
major change occurred during the shipping (transit) time.

Table 18 shows that the NSSC wastes contain higher color, TOG, BOD, vola-
tile solids, ash, and total solids but lower sulfate content than-kraft
decker effluent.  The data further show that carbonation of lime-treated
wastes increased color by 11-llj percent and TOC by 10 percent (only in
one case TOC dropped by 20 percent).   Similar increase in color and TOC
was noticed after carbonation in the case of lime-treated effluents from
IPCO (see Table l).

This increase could be due to the release of chromophores during car-
bonation which were previously "shielded" by the presence of lime.

Effect of Freeze-Drying and Storage

Changes in sedimentation coefficients  before and after freeze-drying of
mill effluents were followed for NSSC  wastes only.  It was expected that
kraft decker effluents would behave similar to the ones studied earlier
(see Table 2).  Results are given in Table 19 which show that the sedi-
mentation coefficient values slightly  increase after freeze-drying of
NSSC wastes.   These increases, however, are not very significant and so
it can be said that no appreciable change is occurring in color bodies
during freeze-drying.

      Table 19.   SEDIMENTATION COEFFICIENTS OF NSSC COLOE BODIES
                                 Sedimentation coefficients, Sa
                                    Before            After
          Effluent               freeze-drying    freeze-drying
Untreated NSSC
Lime treated
before carbonation
after carbonation
0.61;

0.7^
0.66
0.8U

0.75
0.70
      aS = Svedberg = 1 x 10~13.

                                   80

-------
INITIAL CHARACTERIZATION OF COLOR BODIES FROM THE KRAFT DECKER
AND NSSC EFFLUENTS

Chemical Characterization

The results of this analysis are given in Table 20.   The data show that
freeze-dried NSSC effluents have higher volatile solids, TOC, and much
higher amounts of sugars than the decker effluents.   Major difference
in sugars is due to very high amounts of xylose in NSSC effluents (see
Appendix II).  Higher sugar content may be the reason for higher BOD
values of the NSSC waste.

The ash was analyzed by emission spectroscopy and the metal analysis is
given in Table 21.  Except calcium and silicon, the amounts of other
metals in most of the samples are the same.  Substantial differences
occur in the amounts of calcium and silicon in similar samples (e.g.,
Batches 1 and 2 of NSSC or decker effluents).  The amounts of silicon
and calcium were, therefore, excluded from the total.  The data in Table
21 further show that on an average about 65 percent of total metals are
removed by lime.  However, metal/TOC ratios  (see Table 22) of the freeze-
dried color bodies from untreated and lime-treated wastes did not change
much, suggesting  a correlation between  the metals and organic carbon and
their removal by  lime.

Spectrophotometric Examination

Visible  and  ultraviolet spectra  of aqueous solutions of the  freeze-dried
decker and NSSC wastes  (before  and after lime  treatment) were determined
at pH  7.6.   Absorptivity values  were  calculated from these spectra by
dividing the absorbance values with  the volatile solids  in grams per
liter.  The plots  obtained are not shown here.   The results showed that:

111 the Case  of_ Decker Effluent  —
All  samples  showed simple absorption curves  in the visible region; the
absorptivity increased as the wavelength decreased.   In the  ultraviolet
 region all samples gave absorptivity maxima between  270-280  nm, indicating
the presence of ligninlike materials.
                                    81

-------
                        Table 20.   CHEMICAL DATA OH FREEZE-DRIEB WASTES FROM COHTIHHITAL CM  COMPAHT  (COHCO)
                                                       (Basis o.d.  Material)
Decker effluent

Yield, g/100 ml
Ash. %
Volatile*, %
Sulfated ash. %
Sodium, %
Calcium, %
Sulfate. %
TOC, %
Total sugars , %

CCUPP-1
0.06
69.1
30.9
79-5
22.U
0.39
35.2
16.3
5-30
Batch 1
CCLTBC-1
0.06
8li.8
15.2
96.0
27. k
<0.10
37-2
8.1
1.18

CCLTAC-l
0.06
85.3
Ik. 7
96.9
29.8
<0.10
36.8
7.6
1.39

CCUPP-3
0.11
71.8
28.2
79.0
20.3
O.U8
33.3
18.5
2.23
Batch 2
CCLTBC-3
0.12
88.9
11.1
102.6
28.0
<0.1
30.1
7-1
1.07

CCLTAC-3
0.13
85.9
Ik.i
99-6
26.1
<0.1
28.2
3.7
0.53

CCUS-2
0.18
50.k
1.9-6
56.2
1U.1
0.70
17.6
30.6
8.13
Batch 1
CCLTBC-2
0.15
70.7
29-3
65-9
17.1
<0.1
20.6
2k. 3
9-13
HSSC effluent

CCLTAC-2
O.lU
71.1
28.9
65-k
17.3
<0.1
20.3
25.8
6.66

CCUS-k
0.16
56.6
fc3-k
63.2
19.8
0.36
2k.5
27. 5
6.6k
Batch 2
CCLTBC-k
0.12
59.6
30.k
76.8
20.6
<0.1
21.. 1.
19.5
5-05

CCLTAC-k
0.13
76.2
23.8
7k. 0
20.6
<0.1
2k.O
19.3
k.ko
^Calculated by difference.
 For individual sugars see Appendix IV.

For ivaple code see Table 18.

-------
Table 21.  5UISSIOH SPECTROGRAPHIC AHALYSIS OF FREEZB-DRIED WASTES FROM COMCO
                               (Basis o.d. Ash)
Metals,
•••••••
Aluminum
Barium
Boron
Calcium
Copper
Iron
Magnesium
Manganese
Silicon
Total*
—'••i i —^— ••— ^^j,
"Total does
For aaaple

-~~—
0.370
0.013
0.018
O.kjo
0.008
0.036
0.200
0.05)1
5.k
0.75
^^•••^••^
not include
code see Tal
Batch 1
CCLTBC-1
0.150
<0.002
0.016
0.098
0.003
0.068
<0.022
0.00k
1.3
0.26
calcium and
)le 18.
Decker effluent
CCLTAC-1.
— _
0.180
<0.002
0.01k
0.089
0.002
0.062
<0.022
0.00k
0.88
0.29
CCUPP-3
0.170
0.007
0.02k.
1.00
0.003
0.076
0.160
0.031
1.10
O.k7
	 	
— ^^— — — .^.^
Batch 2
CCLTBC-3
0.079
<0.002
0.018
O.C50
0.002
0.032
0.023
0.003
0.360
0.16
^— •• .—

CCLTAC-3
~
<0.036
<0.002
0.020
0.052
0.002
0.038
0.033
0.002
0.620
O.Ik

CCUS-2
0.2k
0.012
0.017
2.10
O.OOk
O.OQ2
0.180
0.07k
2.20
0.62

CCLTBC-2
O.O6
0.016
0.086
0.003
0.037
0.050
O.OOk
0.90
0.17
HSSC effluent
CCLTAC-2
O.Ik
0.01k
0.080
0.002
0.068
0.056
0.011
1.20
0.29
CCUS-k
0.22
0.008
0.010
0.039
O.OOk
0.060
0.160
0.038
0.50
Batch 2
CCLTBC-k
<0.07U
<0.003
0.010
0.06k
0.003
<0.036
<0.033
<0.002
0.20
0.17
CCLTAC-k
0.083
<0.003
0.010
0.070
0.003
0.038
0.037
0.003
0.38
0.18
silicon rallies. " 	 ~ 	 —

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        Table  22.   CHANGE  IN METAL/TOG RATIO  DURING LIME TREATMENT
                        OF MILL WASTES  FROM  CONGO
                                               Lime-treated
          Effluent
Untreated
  before
carbonation
   after
carbonation
Decker effluent
Batch 1
Batch 2
NSSC-effluent
Batch 1
Batch 2
0.032
0.018
0.010
0.010
0.027
0.020
0.005
0.005
0.033
0.032
0.008
0.007
       All values based on o.d. total solids.

In the Case of NSSC Effluent -
Also single absorption curves vere obtained in the visible region.  The
absorptivity increased as the wavelength decreased.

In the ultraviolet region the absorptivity values of all samples first
increased slowly, and then rapidly as the wavelength decreased from 3^*0
to 280 run.  There was little change between 255-280 nm, thus giving a
characteristic "shoulder," referred to as maxima.  Below 250 nm the
absorptivity values increase drastically.  Absorptivity values of lime-
treated samples were lower than the untreated ones but the nature of the
absorptivity curves remained almost the same.  This indicated again that
the effluents contain materials which show a ligninlike character.

Effect of_ Lime Treatment

The percentage of color and TOG removal and percentage decrease in ab-
sorptivity during lime treatment of the effluents were calculated and
the results are given in Table 23.

The results show that generally effluents containing NSSC effluents are
not readily decolorized by lime.  Lower TOC removal in this case (com-
pared to decrease in absorptivity at 280 nm) may be due to the fact that

-------
these effluents contain higher amounts of sugars which resist removal
by lime.

        Table 23.   EFFECT OF LIME TREATMENT ON WASTES FROM CONGO

Color removal8", %
TOC removal01, %
Decrease in absorptivity , %
at 1*20 nm
at 280 nm
Decker
effluent
79-0
50.0

52.3
33.0
NSSC
effluent
6U.O
28.0

62.8
35-5
        Note:  Average values from 2 or more samples.
        ^Based on values of effluent samples.
         Decrease in absorptivity caused by lime treatment based
         on volatile solids content isolated from effluents.

Because of lack of material the untreated decker wastes (Batch 1 and 2)
were mixed in a ratio of 1:3 and lime-treated decker waste "before car-
bonation" (Batch 1 and 2) were mixed in a ratio of 1:1.  These larger
mixed amounts were then used for further fractionation.

FURTHER CHARACTERIZATION OF COLOR BODIES FROM
KRAFT DECKER EFFLUENT FROM CONGO

Fractiojiation of_ Color Bodies

Acidification -
Concentrated solutions of color bodies were acidified as before and the
results are given in Table 2k.

The data show that, upon acidification of untreated wastes, 86.5 percent
color and 65.8 percent TOC were recovered in the acid-insoluble fraction.
The acid-soluble fraction contained only 13.5 percent color and 3U.2 per-
cent TOC,  The lime-treated wastes upon acidification yielded 61 percent
color (12.8 out of 21.0) and 37 percent TOC in the acid-insoluble fraction,
and 39 percent color and 63 percent TOC in the acid-soluble.

                                   85

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        Table 2k.  CHANGE IN SOLIDS ISOLATED FROM CONGO EFFLUENTS
                  DUE TO STOICHIOMETRIC LIME TREATMENT
                     (Basis untreated decker solids)
Untreated
decker waste



Fractions
Decker waste
Aci d-ins oluble
Acid-soluble

Co lor a
yield,
%
100
86.5
13.5

TOCD
yield,
%
100
65.8
3*. 2
Lime- treated
decker waste
Color
yield,
%
21
12.8
8.2
TOC
yield,
%
50
18.5
31.5
Reduction due
to
Color,
%
79
85.2
39-3
lime
TOC,
%
50
71.9
8.6
bAPHA color, Pt-Co units.
 Total organic carbon.

Lime treatment removed 85.2 percent color and 71-9 percent TOC from the
acid-insoluble fraction and only 39«3 percent color and 8.6 percent TOC
from the acid-soluble fraction.  In other words color bodies which are
not precipitated by acidification to pH 1.0 are removed to a lesser
degree by lime than those color bodies which are precipitated by acidifi-
cation.  A comparison of "massive" lime treatment of kraft decker wastes
from IPCO (Table 9) and "stoichiometric" lime treatment of kraft decker
wastes from CONGO (Table 2*0 confirms that massive lime treatment has no
advantage over the stoichiometric system with respect to the percentage
color removal.  Slight variations in data are, however, expected as the
wastes are from different mills.

Column Chromat ography

The acid-insoluble and acid-soluble color bodies were fractionated on
Bio Gel columns and XAD-2 resin, respectively.  The results are given in
Table 25 (for details see Appendix IV).  Fraction "A" of the untreated
waste contains 6H percent color (55. ^ out of 86.5) and 69«5 percent TOC
(U5.7 our of 65.8) of the acid-insolubles.  Whereas this fraction in the
lime-treated waste contains only k3 percent color and 16 percent TOC in-
dicating the change in composition taking place during lime-treatment.

-------
The percentage color and TOG removal decreases from Fraction AI to J (Ai

has the highest M^ as it is excluded from the P-60 column).   The average

color and TOC removed by lime were 85.2 and 71.9 percent, respectively.
        Table 25.  FRACTIONATION OF DECKER ACID-INSOLUBLE COLOR
                     BODIES BY COLUMN CHROMA.TOGRAPHY
Fractions
Fraction "A" from P-2
column through P-60
Al a
A 2 through Ai»
Untreated
acid-insoluble
color bodies
Color TOC
yield, yield,
% %
22. U 27. U
33.0 18.3
Lime- treated
acid-insoluble
color bodies
Color TOC
yield, yield,
% %
1.9 1.2
3.6 1.8
Reduction due
to lime
Color, TOC,
% %
91.5 95.6
89.1 90.2
Acid-in soluble color
bodies through P-2
column
    B through E,
    F through J

Unfractionated acid-
insoluble color bodies
55A
llt.O
7.1
1*5-7
i^.l
6.0
5.5
7.6
—
86.5
65.8    12.8
                           3.0
                           8.0
                           7.5
18.5
          90.1
          1*5-7
        93. U
        1*1*. 1*
85.2    71.9
Percentages of yield are calculated on the basis of untreated original
vaste.

^Calculated by difference so that values for A = (Ai + Aj through Ai»).
 Calculated by difference so that values for unfractionated acid-insolu-
 ble color bodies = (A + B through J).
cValues calculated from "yield" data of the solids isolated from un-
 treated and lime-treated effluents.


The acid-solubles were fractionated on XAD-8 resin and results are given

in Table 26.  The data show that the untreated fraction "ill + IV" con-

tained 59 percent color (8 out of 13.5) and 31 percent TOC of the acid-

soluble color bodies.  The same fraction after lime-treatment contained

5U percent color and 31 percent TOC of the lime-treated acid-solubles,

indicating that lime-treatment does not appreciably change the color  and

TOC composition of the acid-soluble color bodies.  The table further
                                   87

-------
 shows that average color and TOG removed by lime from these color bodjcj;
 were 39 percent and 9 percent, respectively.
          Table 26.  FRACTIONATION OF DECKER ACID-SOLUBLE COLOR
                    BODIES BY SORPTION ON XAD-8 RESIN
Untreated
acid-soluble



Fractions
III + IV
I + II
Unfractionated acid-
soluble color bodies
color
Color
yield,
%
8.0
4,2

13-5
bodies
TOC
yield,
%
10.7
17.1

34.2
Lime-treated
acid- soluble
color
Color
yield,
%
4.4
2.4

8.2
"bodies
TOC
yield,
%
9.9
17-9

31.5
Reduction due
to limea
Color, TOC,
% %
45.0 7-5
42.8

39.3 8.6
Percentages of yield are calculated on the basis of untreated original
vaste.
 Values calculated from "yield" data of the solids isolated from un-
 treated and lime-treated effluents.

Characterization of Decker Effluent Fractions
Individual fractions were combined, as before, to give larger acid-in-
soluble fractions "A," C-J, and acid-soluble fractions I + II and III +
IV.

Visible and UV Spectra —
Visible and UV spectra of all fractions were determined at pH 1.6.  Ab-
sorptivity values were calculated by dividing absorbance with volatile
solids concentration in g/1 and the results are plotted in Figures 33-36,

Ultraviolet region (FJLgure 33, and 34) — All samples exhibited an increase
in absorptivity as the wavelength decreased,  A "hump" is also noticed
at 280 nm,  Except for acid-soluble fractions of both untreated and
lime-treated color bodies, all other samples showed a tremendous increase
in absorptivity below 250 nm.  A comparison of Figures 33 and 34 suggests

                                   88

-------
                                           Untreated Waste
                                              Fractions
                                          O A    >  Acid-
                                          Q C-^T  /  insoluble

                                          A I+II ")  Acid-

                                          X ni+ivj soluble
   200
Figure 33,
220      2^0       260      280
                   Wavelength, nm

Absorptivity versus wavelength (ultraviolet range) of Indulin-C
    and untreated kraft decker wastes from CONGO
                                   89

-------
•

*
                                    Lime-Treated
                                   Waste Fractions
                                       O A
                                       D c-j
                                       A rui
                                       X III+IV
                                 260       280      300
                                  Wavelength, run
    Figure 31*.   Absorptivity versus wavelength (ultraviolet range)  of Indulin-C
                  and lime-treated kraft decker wastes from CONGO
                                      90

-------
                                               Untreated Waste
                                                  Fractions

                                            O  A     /   Acid-
                                            0  C-J   J   insoluble

                                            A  I+II  \ Acid-
                                            X  III+IV/  solu:ble
                                 1*80       500      520       5^0      560
                                Wavelength, nm

Figiire 35.»  Absorptivity  versus wavelength (visible range) of Indulin-C  and
                   untreated kraft decker wastes  froia CONGO
580
600

-------
                                    Lime-Treated
                                   Waste Fractions
                                     O A
                                     d C-J
                                     A i-m
                                     X in-nv
                                1*80       500
                               Wavelength, mn
Figure 36.  Absorptivity versus wavelength (visible  region) of Indulin-C  and
                  •untreated kraft decker wastes  from CONGO

-------
that generally the acid-insoluble color bodies (A and C-J)  show lower,
and acid-insoluble color bodies (I + II and III + IV) show  the same or
higher absorptivity values after lime treatment, indicating that most
of the acid-solubles containing UV-chromophores are not removed by lime.

Visible region (Figures 35 an.d 36) —  All samples gave simple absorption
curves.  Only acid-soluble color bodies, III + IV showed higher absorp-
tivities after lime treatment than the untreated fraction indicating
that less color giving carbon is removed from this fraction by lime.

Molecular Weight Distribution —
Molecular weights of the selected fractions of acid-insoluble and all of
acid-soluble components of the untreated and lime-treated color bodies
were determined as before.  The results are plotted in Figures 37a and b.

The data show that acid-insoluble components of the untreated waste are
much higher in My than those of lime-treated acid-insolubles.  The My. of
untreated acid-insoluble color bodies range between approximately 200 to
167,000 whereas after lime-treatment these values drop to < 500 to U2,000
(see Figure 37a).

The My of untreated and lime-treated acid-soluble color bodies  are quite
similar to each other  (Figure  37b).

Figure 38 shows that acid-insoluble color bodies having an apparent My
of less than 500 are not removed by lime-treatment.  The intermediate
range of My 500 to 1*2,000 apparently undergoes partial removal, and over
1*2,000 are completely  removed.  However, about 90 percent removal occurs
above a My of 2500.  It should be mentioned here that My of these kraft
decker wastes is much higher than kraft decker wastes  from another
mill  (compare Figures  13 and lU with 37 and 38).  As a matter of  fact
My 1*2,000 for a lime-treated waste is the highest found so far.   Not
much  change is found in My of  the acid-soluble color bodies after lime-
treatment.  My ranged between  100-550.  Maximum removal in these  color
bodies was about 8.0 percent.
                                    93

-------
Acid-insolubles

  Untreated

  Lime Treated
                                  m

                                  O
                                   X

                                   a?
                              Acid-solubles

                                 Untreated
                                    Lime Treated
                                          IV   III  II   I
                                          Eluate Fractions
                                        (XAD-8 Fractionation)
       AI    A3    B    D    F    H
          A2   Ai»   C    EG    J
             Eluate Fractions
      (Gel permeation chromatography)

Figure 37-  Weight average molecular weight (V^) distribution of
      fractionated color bodies from kraft decker effluent
                    from CONGO  (M  at w2=0)

-------
             100
                      Nonremoval Zone
                                                         Complete
                                                         Removal
                                                           Zone
Partial
Removal
 Zone
             500      10,000   20,000    30,000   1*0,000    50,000
                        M^, acid-insoluble color bodies

         Figure 3d   Weight  average  molecular weight  (M^)  of acid-
              insoluble  color  bodies from kraft decker effluent
             versus percentage of  removal by  stoichiometric  lime

         Charact eri zat ion  —

    results of  the chemical analysis are given in Table 27.  The data
suggest:

        *•   The untreated decker waste contains 0.38 meq phenolic

            hydroxyls  per gram of volatile solids.   This value drops

            to  0.09 after lime  treatment,  roughly about 76  percent

            reduction  and compares  well with the 73  percent reduction
            observed under  the  massive  lime treatment.

       b.   Total sugars  are reduced  from  8.98  to 5.22  g/100  g volatile
            solids, by lime, a  drop of  30.7 percent.

       c.  Methoxyl content of decker waste is reduced from  5.99 to

           3.149 percent  (a drop of 1*1.7 percent).  Acid-soluble fraction
                                  95

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                                 Table  27-  ANALYTICAL DATA ON FRACTIOUS OF DECKER EFFLUEHT FROM COHCO
                                                      (Basis o.d. Volatile Solids)
Untreated decker

Mol. vrt. range
Color recovery, %
A
Ash8, %
Volatile solidsb, %
Phenolic hydroxyls,
men/g
Total sugars0, *
Methoxyl (MeO), %
E»?o
E2..
E-io/MeO ratio
E2*»/MeO ratio
E* 28/Ezto ratio
Ei,tj/E«oo ratio
Indulin-
C
—
—
53.80
1*6.20

1.32
—
21.05
3.9
38.1.
0.16
1.82
0.088
3.ll<
Original
100-167,000
—
71.11
28.89

0.38
8.98
5.99
1.19
12.36
0.20
2.06
0.096
3.01
Acid-insoluble
A
2,000-167,000
6U.O
22. lit
77.86

—
_
10.8o
2.02
19.9U
0.19
1.85
0.101
3.68
C-J
180-<2,000
21.. 6
70.03
29-97

~
__
6.38
1-57
15-70
0.25
2.1.6
0.100
3-86
Acid-soluble
III + IV
300-550
59-3
38.53
61.1*7

—
__
5.51
0.820
11.89
0.15
2.16
0.069
1..51
I + II
<100
31.1
86.97
13.03

__
__
1.1.6
O.UoS
"*.73
0.28
3.21.
0.086
3.86
Original
lOO-Ua.OOO
—
86.83
13.17

0.09
6.22
3-U9
O.568
8.17
0.16
2.3«*
0.070
3.01
Lime-treat
ed decker
Acid-insoluble
A
1,500-1.2,000
1.3. 0
32.71
67-29

	
__
8.65
1.90
18.1.2
0.22
2.13
0.103
3.38
C-J
500-<2,000
69-5
1.9-72
50.28

	
— —
3.1.2
0-805
9.61.
0.21.
2.82
0.081.
3.55


Acid-soluble
III + IV
500-550
53.7
35-90
61.. 10

_—
__
6.72
0.985
1I..25
0.15
2.12
0.069
1..20
I + II
<120
29-2
91.21*
8.76

__

1.26
0.1.00
»t. 53
0.32
3.60
0.088
2.1.8
b Ashed at 600° C, 1 hour.  Ash calculated on Q. d. aaterlal.
cVolatile solids - 100 - % ash.
 For individual sugars see Appendix II.
       EI.J,, Etts, and Ettt are absorptiTitles at indicated wavelengths.

-------
            'I + II" contain the lowest amounts of MeO indicating a  ieu.;l.
            ligninlike character.
        d.   Ratios, Ei^o/MeO, E280/MeO, and E^o/^eo  indicate  that
            except for some greater loss in MeO,  the color bodies are
            quite similar to the lignins in Indulin-C.
        e.   Higher ratios of E^es/Eeoo  indicate that acid-soluble
            fractions III + IV have more open structures  than Indulin-C
            or color bodies of other fractions.  In fact  Indulin-C
            contains material with the least open structure.

Infrared Spectra —
The spectra of this series are very similar to the spectra (of  comparable
fractions)  which were discussed for the decker wastes  from IPCO (Figures
15-17).  Lime treatment seems to produce a carbonyl band  at 1722, but
this cannot be detected in the spectra of any of the subsequent fractions.
The fractions richest in lignin are acid-insoluble; acid-soluble frac-
tions have  lower lignin contents and much greater carboxylate content
relative to aromatic rings.

The interpretation of the spectrum of one particular fraction,  lime-
treated acid-insoluble fraction "C-J," is uncertain because it  contains
so many new bands, including bands in the conjugated carbonyl  region.

Untreated and lime-treated decker wastes (Figure 39) — These samples
give spectra that are very comparable to the two samples  in the other
decker effluent series (Figure 15).  The only obvious  change is that
the untreated material gives a carboxylate band at 1595 which is more
intense than the band at 1^25.  This is the reverse of the relative  in-
tensities of these bands for the other (Figure 15) series. Once again
the lime-treated sample shows a weak band in the carbonyl region at  1722.

Untreated and lime-treated acid-insoluble Fractions "A" (Figure Up)  —
Sulfate and carbonate are more apparent in the lime-treated sample,  and
the ash content is higher for this sample as well  (32.71 percent vs.
22.l^t percent).  The lime-treated sample shows spectral bands  at 700
and 830 which are not seen in the spectrum of the untreated sample.
                                   97

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     «l
     o

     §
     •p

     •H

     9

     3
OO

*000
1
3500
1
3000
t
2500
1 I I
2000 1800 1600
Wave Number,
1
11*00
cm~
i
1200
1
1000
1
800
1
600
1
Uoo
1
200
                     Figure  39*  Infrared spectra of untreated and lime-treated color "bodies

                                       from kraft  decker effluent from CONGO

-------
NO
o
9
+»
-p
n
a
2
H
                       1»000   3500    3000    2500    2000  1800   1600  lUOO  1200   1000   800    600    1»00     200
                                                          Wave number» cm
                            Figure liO.  Infrared spectra of untreated and lime-treated acid-insoluble  color
                                             bodies from kraft decker effluent from  CONGO

-------
 The "bands at  700 and  830 are not seen in the spectrum of the correspond-
 ing fraction  of the other decker system (Figure 16), although weak bands
 at this frequency were evident in the original untreated and lime-
 treated samples.

 The lime-treated sample appears to have a somewhat larger carboxylate
 to aromatic ring ratio than the untreated sample.  This parallels the
 situation found previously (Figure 16).
Untreated__and lime-treated acid- insoluble Fractions "C-J" (Figure
The untreated sample spectrum is very similar to the corresponding
fraction in the previous series (Figure 16) .  This lime-treated fraction
gives an unusual IR spectrum.  The spectrum of lime-treated acid-
insoluble fraction "C-R" (Figure 16) vas also atypical, but it differs
considerably from that of the lime treated acid-insoluble fraction
(Figure
In the lime-treated fraction, there are again bands at TOO and 832, as
was the case for the lime-treated fraction "A" (Figure kO) just discus-
sed in the previous section.  There appears to be a small sulfate content
even though ash content is quite high (^9-72 percent).  The region from
1550-1700 is very unusual; bands are present at 1562, 1615, 166U and a
shoulder at 1690.  The latter two frequencies reside in the conjugated
carbonyl region.  Lignin bands are either very weak or nonexistent.  The
C-H and 0-H absorptions are comparable to those of the other fractions,
however.

Untreated and lime-treated acid-soluble Fractions "I + II" (Figure *tl) —
These spectra are nearly identical and very rich in sulfate (ash contents
are 87 and 91 percent).  The corresponding fractions in the other decker
effluent (Figure 17), gave spectra that are nearly identical with these
spectra.
Untreated and lime-treated acid-soluble Fractions III + IV (Figure
These spectra are almost identical.   There may be a slightly higher con-
centration of lignin-related aromatic rings in the lime-treated system;
                                   100

-------
o
H
                      •p
                      -p
s
S-,
                                           Lime-Treated
                                             •• III-HV
                                         Lime-Treated
                                           "I+II"
                                          Untreated
                                           "I+II"
                        1*000  3500  3000  2500   2000  1000  1600  lUOO  1200 1000  800  600  UOO   200
                                                      Wave Number, r-m-1
                           Figure Ul.  Infrared spectra of untreated and lime-treated acid-soluble
                                     color bodies from kraft decker  effluent frctn CONGO

-------
this is based on the higher methoxyl content  (6.72 percent vs. 5-51 per-
cent) and the greater prominence of lignin bands at 1510, 1270, and 10^5
cm"].

The  region between lUOO and 1650 cm"1 is dominated by carboxylate bands.
The  ratio of carboxylate to aromatic ring absorption is much greater
than is the case with the acid-insoluble fractions which also had high
lignin content.

Pyrolysis Gas Liquid Chromatography —
Qualitative pyrolysis-GLC was run on untreated and lime treated decker
effluent from CONGO.  The chromatograms are given in Figure k2.  The
peak numbers are comparable to those in Figure 18.   A comparison of
Figure *+2 and 18 shows that the color bodies in decker waste from CONGO
is more like Indulin-C.  Note that peaks 21, 23, 28, 29, 31, 31a, and
32 which have been identified in Indulin-C (Figure 18, Table 13) are
also present in CONGO'S decker effluent.  Lime-treated waste also gives
these materials but in lesser relative concentrations.  It seems that
more degraded and modified color bodies are present in decker effluent
from IPCO discussed earlier.  Unidentified peaks 36, 38, 39, and hQ are
present in both effluents.

FURTHER CHARACTERIZATION OF COLOR BODIES FROM NEUTRAL
SULFITE SEMICHEMICAL (NSSC) EFFLUENT FROM CONGO

As has been mentioned earlier, the effluent containing major amounts of
wastes from NSSC mills are named as "NSSC-effluent."  The minor compo-
nents of this effluent are other wastes from the pulping and papermaking
stage.  This is the effluent which is being treated by lime at CONGO'S
treatment facility at Hodge, Louisiana.

Fractionation of_ Color Bodies

Acidification —
Acidification of concentrated aqueous solutions was carried out similar
to other effluents.  The results are given in Table 28.   The data show

                                   102

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Lime-treated decker
Time, mi
Temp,, °
,. .. 1. 1
n 1»U 1*0
C < 	 200

3b

1
32
4

i
28
187
--J
2k
171
I
20
155
i
16
139
i
12
123
I
8
107
i
Ji
91
	 	 j
0
75
 Figure te.  Pyrolysis gas chromatograas of untreated and lime-treated
                      decker effluents from CONGO
                              103

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that upon acidificatiori 1*8.2 percent color and 36.0 percent TOO were
recovered in the acid-insoluble fractions.  The acid-soluble fraction
contained more color  (51.8 percent) and more TOG  (6k percent) than the
acid-insoluble.  The  lime-treated wastes on the other hand yielded 57.8
percent color  (20.8 out of 36) and 51 percent TOG in the acid-insoluble
fraction compared to  1*2 percent color (15-2 out of 36) and 1*9 percent
TOG in the acid-soluble.  This is different than  the situation found in
decker effluents vhere major portions of color in the untreated waste
was found in the acid-insoluble component.  Table 28 further shows that
lime-treatment removes more color and TOG from the acid-soluble color
bodies (70.6 and 1*6.1* percent).
        Table 28.  CHANGE IN SOLIDS ISOLATED FROM CONGO EFFLUENTS
                  DUE TO STOICHIOMETEIC LIME TREATMENT
Untreated
NSSC waste



Fractions
NSSC waste
Acid- insoluble
Acid-soluble

Colora
yield,
%
100
1*8.2
51.8

TOCD
yield,
%
100
36.0
61*. o
Lime- treated
NSSC waste
Color
yield,
%
36
20.8
15.2
TOG
yield,
%
70
35.7
3U. 3
Reduction due
to
Color
%
61*
56.8
70.6
lime
, TOG,
*
30
<1.0
1*6.1*
 APHA color, Pt-Co units.
 Total organic carbon.

Column Chromatography —
The acid-insoluble and acid-soluble color bodies were fractionated as
before on Bio-Gel and XAD-8 columns, respectively.  The results are
given in Table 29 (for details see Appendix V).

The data show that Fraction "A" of the untreated acid-insoluble color
bodies contains 32.1+ percent color (15.6 out of 1*8.2) and 1*5 percent
TOG.  The lime-treated Fraction A contains 30.3 percent color (6.3
out of 20.8) and 27.0 percent TOC.
                                   10 U

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          Table 29.   FRACTIONATION  OF  NSSC ACID-INSOLUBLE  COLOR
                     BODIES BY  COLUMN  CHROMATOGRAPHY
Fractions
Fraction "A" from P-2
column through P-60
AI
A2
A3 + AH&
Untreated
aci d- in soluble
color bodies
Color TOG
yield, yield,
% %
7.U 9.6
5.5 6.3
2.7 0.3
Lime-treated
acid-insoluble
color bodi.es
Color TOC
yield, yield,
% %
l*.l U.3
1.9 ^.2
0.3 0.8
Reduction due
to lime
Color, TOC,
% %
UU.6 55-2
65. U 33. U
88.9
Acid-insoluble color
bodies through P-2
column

         A
    B through J

Unfractionated acid-
insoluble color bodies
15.6
32.6
H8.2
16.2
19.8
36
 6.3
 1*.5
20.8
 9.3
26.U
35.7
59.6
55-5
56.8
U2.6
Percentages of yield are calculated on the basis of untreated original
waste.

^Calculated by difference so that values for A = (Ai + Aa + Aa + A«»).
 Calculated by difference so that values for unfractionated acid-insolu-
 ble color bodies = (A + B through J).
°Values calculated from "yield" data of the solids isolated from un-
 treated and lime-treated effluents.


The average color and TOC removed from acid-insoluble color bodies

were 56.8 percent and < 1.0 percent, respectively (TOC removal fig-

ures are much lower than expected).


The acid-soluble color bodies were fractionated on XAD-8 resin and the

data are given in Table 30.  The results show that on the basis of un-

treated acid-soluble material Fractions III + IV combined contain 52.1

percent color  (27 out of 51.8) and U?.5 percent TOC (30.2 out of 6U),

whereas on the basis of lime-treated material this combined fraction

had 57.2 percent color and 29.5 percent TOC.  The data further show

that  average color and TOC removed from acid-soluble  color bodies were

70.6  and  k6.h percent, respectively.   (These are based on actual  deter-

minations  and not on mathematical averages  from the data on fractions.)
                                    105

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           Table  30.  FRACTIONATION OF NESC ACID-SOLUULE COLOK
                     BODIES BY COLUMH CHROMATOGHAPHY
Untreated
acid-soluble
color bodies
Fractions
IV
III
II
I
Unfractionated acid-
soluble color bodies
Color
yield,
15.1
11.9
15-9
5-2
51.8
TOC
yield,
19.2
11.0
23.6
10.3
61*
Li me- treated
acid-soluble
color bodies
Color
yield,
6.0
2.7
1*.5
1.6
15.2
TOC
yield,
6.3
3.8
11.3
5-5
3l+. 3
Reduction due
, , . a
to lime
Color,
60.3
77-3
71.7
69-2
70.6
TOC,
67-2
65.5
52.1
1*6.5
1*6. U
Percentages of yield are calculated on the basis of untreated NSSC waste.
Values calculated from "yield" data of the solids isolated from un-
 treated and lime-treated effluents.

It can be concluded that in the case of untreated color bodies most of
the color and TOC are obtained in the acid-soluble fractions, whereas
in lime-treated samples it is the opposite.  Lime removes more color
and TOC from the acid-soluble color bodies.

Characterization of Effluent Fractions —
Individual fractions from chromatography columns were later combined
to give larger acid-insoluble fractions "A" and C-J, and acid-soluble
fractions I + II and III + IV.

Visible and UV-Spectra -
Absorptivity values from the spectra at pH 7-6 were calculated as before
and plotted in Figures 1*3-1*6.  As no "lignin" such as "indulin-C" for
kraft, was available for NSSC effluent, the absorptivity values of
Indulin-C vere,  therefore, used for comparison.
                                   106

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                                       Untreated Waste
                                          Fractions

                                                Acid-
                                                insoluble

                                                Acid-
                                                soluble
200
220
                              260      280
                              Wavelength, nm

Figure 1*3.  Absorptivity versus wavelength (ultraviolet range) of Indulin-C
                    and untreated NSSC vaste from COM CO
                                  10?

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                    Lime-Treated
                  Waste Fractions
 200


Figure
220
300
320
                  260      280
                  Wavelength, nm
Absorptivity versus wavelength (ultraviolet range) of Indulin-C
      and lime-treated NSSC waste from CONGO
                          108

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o
vo
               380
                                                                       Untreated Waste
                                                                          Fractions
                                                                    O  A    ~) Acid-
                                                                    D  C-J  > insoluble

                                                                    A  i+n
                                                        Acid-
                                            X   m+ivj  soluble
1*00
U20
                              Figure
U60
520
                                                                                                     560
                      U80       500
                     Wavelength, nm
-  Absorptivity versus wavelength (visible region) of Indulin-C  and
             untreated NSSC waste from CONGO
580
                                                                                               600

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          7-00-
H
H
O
                                                             Lime-Treated
                                                              Fractions
                                                            O A

                                                            a c-
                                                            A i+n

                                                            X in+iv
UOO      1>20


      Figure
UO
1*60
                                     520
                                     5^0
560
                                                           U80       500
                                                         Wavelength, ma

                                       Absorptivity  versus wavelength (visible region) of Indulin-C  and
                                                line-treated NSSC waste from CONGO
580
600

-------
Ultraviolet region (Figures ^3 and kk)  — All samples exhibited an increase
in absorptivity as the wavelength de-creased.   The spectra also show
"shoulders" at 280 and 205 nm.  Generally,  the untreated acid-soluble
color bodies have lower absorptivity values than untreated acid-insoluble
color bodies.  This trend changes after lime treatment.   Except acid-
soluble Fractions III and IV, all other fractions showed a decrease in
absorptivity after lime treatment.  The values for Fraction III + IV
did not change much after lime treatment.  Indicating that either the
color bodies from this fraction are not removed  at all or, if they are,
they are removed in the same ratio so that  the absorptivity does not
register any change.   From previous data (Table 30) it is seen that about
1*6 percent TOC is in fact removed by lime.

Visible region (Figures 1*5 and U6) — All samples gave simple absorption
curves and the absorptivities of all lime-treated fractions were lower
than the untreated ones, indicating the removal of more color bodies.
Surprisingly, the untreated acid-insoluble  Fraction C-J and acid-soluble
Fraction III + IV had higher absorptivity in the visible region than the
untreated Fraction "A."

Molecular Weight Distribution —
Molecular weight ranges are plotted in Figures ^7a and b.  The results
show that the weight average molecular weights of untreated acid-insol-
ubles range from 600 to ^0,000 and that of lime-treated acid-insolubles
from 300-25,000.  The acid-soluble color bodies before lime treatment
range from UOO-1200 and after lime treatment from 200-800.

The percentage removal data fluctuated so that definite relationships
between percent removal and M^ could not be drawn.  However, it was
established that acid-insoluble color bodies having My. of 300 were not
removed by lime.  There was a partial removal in M^ range of 300-25,000
and over 25,000 complete removal occurred.   Data further showed that
only a very small amount of material fell in the high My. range.
                                   Ill

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    35
    30
    25
 H  20
    15
    10
      -D
        I  I   I  I
                               Acid-solubles
                                   Untreated
                                         e Treated
                                               IV   III  II   I
                                               Eluate Fractions
                                             (XAD-8 Fractionation)
Acid-insolubles

    Untreated

   Lime treated
A3
            H
                 B   D   F
         A2   Ai»   C    E    a   J
           Eluate Fractions
      (Gel permeation chromatography)

Figure ^7.   Weight average molecular weight (My) distribution of
          fractionated color bodies from NSSC effluent
                    from CONGO (M  at u?-0)
                            112

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The acid-soluble color bodies behaved differently in NSSC effluent.   In
these color "bodies, those above MW of 770 were completely removed, be-
low My. 230 were not removed and partial removal occurred in the inter-
mediate range of 230-770.  Maximum My. found in untreated acid-soluble
color bodies was 1150.  About 65 percent removal occurred at M^ of 720,
so that between M^ 720 and 770 the percentage removal jumped from 65 to
100 percent.

Chemical Characterization —
The results of the chemical analysis are given in Table 31.  The results
show:
     a.  The meq phenolic hydroxyls per gram of volatile solids
         do not change appreciably during lime treatment.  In
         all other effluents it was reduced.
     b.  The amount of total sugars per gram of volatile solids
         increases by about 62 percent after lime treatment,
         indicating that more of the non-sugar volatile solids
         compared  to the sugars are removed.
     c.  Average methoxyl  content  in the  unfractionated  (original)
         waste  decreases from  7.72 to  6.97 percent  (9-7 percent
         reduction),  indicating that the  ratio of MeO to volatile
         solids remains  ajbipst unchanged  by lime treatment.  This,
         however,  does not agree with  the fact that sugars  are
         not  removed.  Appreciable reduction  in  MeO occurs  in
         Fraction  "C-J"  during lime  treatment.   It  cannot be
         established whether this  reduction  is real or  caused
         by preferential carbon  fractionation  in Bio-Gel  columns.
      d.  Higher £1,20/MeO ratio of untreated acid-soluble
          Fraction  "I + II" indicates loss of MeO in this  fraction.
          It is  also substantiated by higher Eaao/MeO,  and E^o/Eaeo
          ratios indicating higher color compared to the aromatic
          nature.
      e.   Ei»65/E6oo ratios  indicate that all fractions have more
          open structures than Indulin-C.

                                    113

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                                 Table  31.
                                            AHALYTICAL DATA OH FRACTIOUS FROM HSSC EfTLUHTT FROM COBCO
                                                           (Basis o.d. Solids)
Untreated HSSC

Mol. wt. ranpe
Color recovery, I
Asha, %
Volatile solidsb, *
Phenolic hydroxyls, neq/g
Total sugars0, %
Methoxyl (MeO), %
E»20
Ej.D
En 20 /MeO ratio
E2t«/MeO ratio
EHIO/EZIO ratio
E»ss/Etoo ratio
Indulin-
C
—
53.8
1.6.20
1.32
21.05
3.9
38.1.
0.16
1.82
0.086
3.14
Acid— insoluble
Original

56.6
I.3-4
0.39
10.79
7.72
1.37
11.66
0.177
1.51
0.117
3.02
A

16.79
83.21
~~
14.60
1.47
15.69
0.101
1.07
0.094
3.61
C-J

59-29
40.71
I
11.22
2.14
17.89
0.191
1-59
0.120
4.44
Aci d-soluble
III + IV

39-90
"60.10
—
8.88
1.68
13.45
0.189
1.51
0.125
4.43
I + II

60.00
40.00
—
4.13
1.32
8.7
0.320
2.11
0.152
H.15
Original

76.2
23-8
0.38
17.25
6.97
0.51
7.54
0.073
1.08
0.067
4.0
Lime-treated HSSC
Acid-insoluble
A C-J

19.26
80.74
—
15.33
0.901
11.92
0.059
0.778
0.076
3.58

71.32
28.68
—
7.71
1.08
11.46
0.14
1.49
0.094
3.89
Acid-soluble
III + IV

37.58
62.42
—
9-01
1.03
12.84
0.114
1.43
0.080
4.66
I + II

60.51
39-49
—
3.24
0.476
5.98
0.1U7
1.85
0.080
3.62
.Ashed at 600°C, 1 hour and calculated on o.d. material.
^Volatile »olids " 100-Jl ash.
 for individual sugars see Appendix IV.
Ej»e,
           , Ei,«s. and £«•• are absorptirities at  indicated ware length*.

-------
Infrared Spectra —
The IR spectra for this series do not reveal significant differences  in
the organic material that could be attributed to lime treatment.   Sul-
fate and, in the case of lime-treated samples, carbonate are the  most
obvious inorganic components present.  Sulfite does not  seem to be pres-
ent, but it is not possible to rule out small amounts of thiosulfate.
This series is distinguished from the others by bands suggesting  the
presence of lignosulfonates in small amounts.

The region 1 1*00-1650 cm"1 is particularly interesting in distinguishing
differences between acid- insoluble and acid-soluble material.   The ratio
of intensities of carboxylate bands to aromatic ring bands in this re-
gion is much higher for the acid-soluble materials than  for the acid-
insoluble materials.  The acid-soluble fractions thus seem to have a
much higher carboxylate content and this increased polarity is undoubt-
edly a major factor in determining solubility.
Untreated NSSC vaste (Figure ^8) — The intensity of the broad band at
3UOO cm""1 agrees vith the high water content of this sample.   Sulfate
is evident as a major component of the ash, giving bands at 11 Uo and
620.  There is no sign of sodium sulfite in this spectrum or in any
of the spectra of fractions.  A weak band at 995 may be indicative of
thiosulfate.  The carboxylate bands are quite intense at 1575 and lUlO.
Lignin is probably responsible for the band at 10^0 and shoulders at
1U60 and 1510.

The region between lUOO and 1600 is quite interesting in this series.
The appearance of absorption is thought to reflect the relative amounts
of carboxylate salt groups and aromatic nuclei present.  In this sample
the carboxylate salt groups are quite dominant, and their broad bands
overlap the aromatic bands of the lignin so that the latter appear only
as shoulders.  The relative amounts of these groups change dramatically
during fractionation as will be pointed out in the ensuing discussion.
One other distinctive feature of the spectrum is the shoulder at 655
and weak broad band at 530.  This is attributed to lignosulf onate , which
is a reasonable component for this particular effluent.
                                   115

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0\
                                 Lime-Treated NSSC
        Uooo
3500     3000     2500      2000   1800   1600   1^00
                                   Wave Number, cm 1
1200
1000
800   600
Uoo
                                                                                                             200
                         Figure 1*8.   Infrared spectra of untreated and lime-treated color bodies
                                              from NSSC  effluent  from CONGO

-------
Lime-treated NSSC waste (Figure H8) — The general appearance of the spec-
trum is very similar to that of the untreated sample.  The lignin bands
are less evident in the lime-treated sample at 1500 and 10UO cm"1.

The sulfate bands are comparable to those in the spectrum of the un-
treated sample.  The presence of carbonate is suggested by the broaden-
ing of the band at lUlO in the untreated sample to a wide maximum (lUlO-
11+50) in the lime-treated sample.   Further evidence for carbonate is
the sharp peak at 8?5 cm'1, which is also noted in other lime-treated
samples in other series.  Evidence for a small amount of lignosulfonate
is also present in this spectrum.

The disappearance of the lignin band at 1510 cm'1 does not necessarily
signify a marked structural change in the lignin systems resulting from
action of lime.  This lignin band could have been simply obscured by the
combined influence of neighboring carboxylate and carbonate bands.

Untreated acid-insoluble Fraction "A" (Figure 1*9) - This fraction is
comparatively low in ash and the sulfate content is clearly much lower
than is the case for the original effluent sample (judging from the ab-
sorption at 1130 and lack of absorption at 620).  The lignin-related
bands at 1030 and 1500 are quite intense as would be expected from the
high methoxyl content of lU.6 percent.  A band at lii60 is also quite
prominent and this, too, may be largely representative of the aromatic
systems in lignin.

Careful comparison of the 1^00-1650 for this fraction (Figure U9) and
for untreated NSSC waste (Figure U8) suggests that the relative amounts
of lignin (aromatic systems) and carboxylate salts are very different in
the two samples.  Although it is not possible to make even semiquantita-
tive statements, it appears that this region is dominated by lignin-
related bands for the acid-insoluble fractions (though to a lesser ex-
tent for untreated acid-insoluble Fraction "C-J," whereas it is dominated
by carboxylate salt bands for the acid-soluble fractions and the un-
treated NSSC waste.
                                   117

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OO
                                       Lime-Treated
                                           C-J"
                                       Untreated "C-J"
                 1*000     3500   3000    2500   2000  1800  1600  ll+OO  1200  1000   800   600  UOO    200
                                                    Wave Number, cm 1

                         Figure k9.   Infrared spectra of untreated and lime-treated acid-insoluble
                                         fractions from NSSC effluent from CONGO

-------
Thus, the distinctive feature of the acid-insoluble fractions seems to
be the relatively high ratio of lignin (or aromatic rings) to carboxyl-
ate systems.  The lower polarity implied by this analysis would be
expected to result in lover water (or acid) solubility, as is indeed
the case.

Lime-treated acid-insoluble Fraction "A" (Figure kg) ~~ This sample appears
extremely similar to its untreated counterpart.  The ash content, methoxyl
content, and the IR spectra show few differences.  The ratio of lignin
bands to carboxylate bands in the 1UOO-1650 region is almost identical
in the two spectra.  There are no differences significant enough to be
interpreted as results of the lime treatment.

Untreated acid-insoluble Fraction "C-J" (Figure t>9) — There is a high
ash content (59.29 percent) and a substantial part of it is sulfate,
since there is a broad maximum at 1120 and related absorption at 620.
This is a distinct difference relative to the untreated Fraction "A."
Although bands at 1505 and 1030 and a methoxyl content of 11.22 percent
suggest a considerable amount of lignin, this fraction is much richer  .
in carboxylate salt content than untreated "A."  This is deduced from
the relative band intensities in the 1^00-1650 region.

Lime-treated acid-insoluble Fraction "C-J" (Figure U£) — In comparing
the spectrum of this fraction with its untreated counterpart, again
there is little difference that could be attributed to the lime treat-
ment.  In the region 2900-3200 there are new bands apparent, and the
band at ikOO is sharper and more intense than it usually is.  This, how-
ever, is thought to be due to production of an artifact-ammonium ion
during the column fractionation.  This is even more clearly revealed in
the untreated "C-H" (see Figure 26), which was obtained at the same
fractionation stage but came from a caustic extract effluent.

Acid-Soluble Material -
Untreated acid-soluble Fraction "I+ II"  (Figure 50) — This sample is
characterized by high ash  (60.00 percent)  and the lowest methoxyl  content
                                    119

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o

§
•p
•p
ft
e
01

§

EH
                       Lime-Treated

                        "III+IV"
                                     1800  1600  lUOO  1200   1000   800
JtOOO  3500   3000   2500
                                    Wove Number, cm
         Figure 50-  Infrared spectra of untreated and  lime-treated acid-soluble

                       color bodies from NSSC effluent  from  CONGO

-------
(It. 13 percent) of any of the five untreated NSSC waste fractions (the
original NSSC effluent sample and the four fractions derived from it).

A substantial component of the inorganic material appears to be sulfate,
as seen by strong bands at 11*40 and 625.  A probable lignin-related band
is quite prominent at 10^0.  The region betveen l^tOO and 1650 is domi-
nated by the carboxylate salt bands at 1^10 and 1605.   The lignin-related
bands at 1500 and about 1^60 are seen in this spectrum only as shoulders.

The general appearance of this region, and even the entire spectrum, is
very similar to that seen for the untreated NSSC vaste sample.  The
primary difference between the organic material in this fraction and
the organic material present in the acid-insoluble fractions is that
the ratio of carboxylate groups to lignin-related ring systems is much
greater for the acid-soluble sample.  The suspected lignosulfonate band
at 530 is most prominent in the spectrum of this acid-soluble material.

Lime-treated acid-soluble Fraction "I + II" (Figure 50) — This lime-
treated fraction has ash (60.51 percent) and methoxyl content (3«2l* per-
cent) comparable with its untreated counterpart discussed above.  The IR
spectra of these fractions are virtually identical and the effect of
lime treatment is not at all apparent from the IR spectra.

Untreated acid-soluble Fraction "III + IV" (Figure 50) — This sample con-
tains lower ash (39.90 percent) and higher methoxyl (8.88 percent) than
the other acid-soluble fraction just discussed.  The spectrum suggests
that lignin content is indeed higher since prominent bands are present
at 10U5 and 1210.  Sulfate may be contributing to the absorption at 1120
and 625.  Weak bands whose origin is uncertain, are seen at 925 and 650.
The 925 band is also evident in the untreated NSSC sample,, but the 650
band would be masked by sulf ate absorption.

The region between lUoo and 1650 is quite similar to that of the other
acid-soluble fraction ("I + II"), suggesting that both acid-soluble
fractions contain organic material that has a relatively high ratio of
carboxylate to lignin-related ring systems.  This ratio  appears  similar
                                   121

-------
to that of the original untreated sample Taut is clearly much higher than
is the case for the acid-insoluble fractions.

The primary difference between the two acid-soluble fractions seems to
be that of inorganic content.  Molecular weight differences may also
exist but could not be detected from the IR spectra.

Lime-treated acid-soluble Fraction "III + IV" (Figure 50) — Again there
is no significant difference in ash content, methoxyl content, or IR
spectra between this fraction and its untreated counterpart.

Fyrolysis Gas Liquid Chromatography —
Qualitative pyrolysis GLC was run on untreated and lime-treated NSSC
effluent from CONGO.  The chromatograms are given in Figure 51.  Both
chromatograma are quite similar.  The color bodies in NSSC waste con-
tain some of the compounds obtained by pyrolyzing Indulin-C.  Note the
peaks marked 21 to 32,   These have been previously identified (see
Figure 18 and Table 13).
                                   122

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Time, Bin
Temp.
             Figure 51.   Pyrolysis  gas  chromatograms of untreated and lime-treated
                                   NSSC effluents  from COHCO
                                           123

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                               SECTION VI

                     LIME TREATMENT WITH METAL IONS

It was mentioned in the Introduction of this report that the objective
of this phase of our study was to establish an improved lime treatment
system for the removal of color from kraft decker effluents, kraft
bleach caustic extract and NSSC effluents.

BACKGROUND INFORMATION

James, in his book entitled "Water Treatment" (Technical Press Ltd.,
1965, p. 110-14), mentions that sufficient lime is added to water to
combine with the free carbon dioxide and then to convert the bicarbo-
nates of calcium and magnesium into carbonate and hydroxide, respec-
tively.  He further indicates the use of iron salts in clarification
and subsequent addition of alkali to precipitate the iron.  Small
amounts of lime have also been used to produce "ferric floes."

Although the use of lime as a water softener is quite old, its use as
a color fiocculant in kraft industry is fairly recent.  Lime precipita-
tion has been shown to remove certain solid constituents and 85 to 90
percent of color from the kraft pulping waste.  Excessive amounts of
lime (over the minimum required) have no apparent effect on percentage
of color removal.  Preliminary studies at the Institute have shown that,
by the addition of certain multivalent ions with lime, practically all
of the color is removed.

The objective of this work was to establish conditions for such an "im-
proved lime-treatment system."  This study was divided into 3 major
steps:

     1.  Treatment of mill wastes with metal ions.
     2.  Treatment of mill wastes with varying metal ion
         concentration and constant lime  concentration.
     3.  Treatment of mill wastes with varying lime
         concentration and constant metal ion  concentration.

                                    125

-------
TREATMENT OF MILL WASTES WITH METAL IONS

Preliminary color removal studies were performed on untreated kraft
wastes from the decker and the caustic extraction stages using salts
such as alum, "barium chloride, ferric chloride, magnesium hydroxide
and zinc chloride.

Concentrated salt solutions (6000 ppm) were individually prepared and
stored for future use.  Freeze-dried color bodies from decker and caus-
tic extraction stages were dissolved in distilled water to give 0.1 per-
cent solutions which, eventually, were used for this study.

The desired amount of salt solution to give 100-1000 ppm salt per 50  ml
total volume was measured into graduated cylinders and filled to the
50-ml mark with the waste to be evaluated.  Mixing was accomplished by
inverting the graduates five times.  The treated effluent was then al-
lowed to stand undisturbed for a minimum of 15 minutes prior to centri-
fuging to remove flocculated material.  Each treated sample was centri-
fuged for 15 minutes at 9000 rpm.  The clear supernatant was carefully
poured off and stored until tested for pH, color, absorbance, and total
organic carbon (TOG).  Only the ferric chloride treatment was run in  two
series.  In one the pH was not adjusted and in the other pH was adjusted
to about 9.0 with NaOH to produce "ferric floe" and then centrifuged.
The sediment was discarded.

The percentage of removal of color and TOG were calculated from the data
obtained (absorbance values at 280 nm were not very reliable because  of
interference by ferric ion) and the results are given in Tables 32 and
33.  Only the color removal values are plotted against salt concentra-
tion in moles/liter in Figures 52 through 55.

A comparison of Figures 52 and 53 shows that BaCl2 is a better color
removing agent for decker effluent than for caustic extract.  At the
concentrations studied Mg(OH)2 was the least effective.

Figures 5U and 55 show that alum is more effective in the case of decker
effluent than caustic extract, whereas FeCl3 is more effective on caustic
                                   126

-------
              Table 32.  TREATMENT OF KRAFT EFFLUENTS WITH BIVALENT IONS
Decker effluent
Salt
ppm
Mg(OH)2
0
100
200
250
300
350
1*00
600
ZnCla
0
100
200
250
300
350
1*00
600
BaCla
0
100
200
250
300
350
1*00
600
800
1000
Ca(OH)?
0
100
200
250
300
350
1*00
600
concentration
10"1* moles /I

— —
17.15
3>*. 3
1*2.9
51.5
60.0
68.6
103.0

M
7.3U
11*. 68
18.33
22.0
25.7
29.33
Wt.O

— —
U.8
9.6
12.0
11*. I*
16.8
19.2
28.8
38.1*
1*8.0

__
13.5
27.0
33.8
1*0.5
1*7.3
51*. o
81.0
Final
pH

7.2
7.1*
7-5
7.8
8.0
8.0
8.1
8.0

7.2
6.9
6.5
6.5
6.1*
6.3
6.2
6.0

7.2
7-3
7.2
7.1
7.0
6.9
6.7
6.1*
6.2
5-7


__
-_
_—
*~
__
— —
—
Color
removal ,
%

....
0
2.5
2.5
5.0
2.5
7.5
7.5

__
2.5
5.0
7-5
12.5
17.'5a
22.5
1*5.1*

^ m
5.0
16.7
21.7
23.3
26.7
28.3
1*1.2
1*2.5
61.2


M.
*.
«
VM
— —
H
	
TOC
removal ,
%

— _
3.3
3.5
6.2
3.9
5.9
11.3
15.1*

__
5.3
8.9
13.3
13.6
13.9
17.7
1*0.8

— ^
6.5
8.3
9-5
10.1
13.3
13.6
21*. 3
31.1*
1*0.8

__
~
—
__
—
m
__
~
Caustic extract
Final
pH

8.2
8.1*
8.7
8.9
9.0
9-0
9.1
9.2

8.1
6.9
6.7
6.7
6.7
6.7
6.7
6.7

7.1
6.9
6.5
6.5
6.6
6.8
6.9
7.0
7.1
7.1

8.6
10.3
11.3
11.6
11.7
11.8
11.9
12.1
Color
removal ,
%

— —
0
6.8
11.1*
11.1*
11.1*
12.0
22.8

«.
0
3.9
3-9
13.6
13.1*
22.9
1*1*. 0

__
0
0
0
+1.3
U.I
1.1
23.7
35-9
1*5.2

~—
20.0
22.5
22.5
25.0
32.5
62.5
72.5
TOC
removal ,
%

__
1.6
>».5
5.7
8.0
l*. 5
7.1*
13.2

«
2.8
7.1*
8.1*
11.1
11*. 3
21.3
1*6.5

__
6.0
U.3
6.3
6.6
9-8
9-8
20.0
33.1
1*2.9

—
—
—
—
—
__
__
—
Calculated value.
                                          127

-------
Table 33'.   TREATMENT OF KRAFT EFFLUENTS WITH TRIVALEHT IONS
Decker effluent
Salt concentration
ppm
Alum
0
100
200
250
300
350
1(00
600
FeClj
0
100
200
250
300
350
1(00
600
PeCli
0
100
200
250
300
350
1(00
600
10~" moles/1
(Ali(SOjs«l8H20)

1.1(2
2.81*
3.55
U.26
U.97
5.68
8.51
— gH_ unadjusted
wv
6.2
12. 1*
15.1(5
18.5
21.6
2U.7
37.0
— pH adjusted
••••
6.2
12. 1*
15A5
18.5
21.6
2U.7
37.0
Final
PH

7.2
7.3
5.1
k.T
I*. 6
"*.5
1».5
"i.5

7-2
5.8
5.0
l*.l
3.8
3.7
3.U
3.1

7.2
8.2
8.7
fl.3
8.5
8.9
8.9
8.8
Color
removal ,
%


59.1
87.1
90.9
88.1
88.2
88.2
86.8

••_
27-3
75-5
76.1*
77.3
77.3
75.5
76.1»

__
0
21.1
12.6
38.9
58.3
50.9
72.5
TOC
removal ,
*


23.9
—
__
—
58.0
52.8
514.2

«•
22.0
5U.8
66.6
66.9
59.8
65.3
68.1

_ _
19.3
58.9
67.1
70.3
65.6
69-9
71.2
Caustic extract
Final
PH

7.9
6.5
U.8
U.l»
U.3
U.2
1*.3
U.I

6.7
6.1
5.6
5.1
U.8
U.I.
U.l
3.8

6.7
8.1*
8.9
8.7
9.1
8.6
8.1
7.8
Color
removal ,
%


7.7
63.1
85.2
8U.6
85.2
8U.6
86.5

— —
0
2U.U
26.9
51.3
7U.8
91.7
90.7

__
0.6
67.1»
83.1
97.2
97.3
97-3
97.1*
TOC
removal ,
%


22.1
6U.5
7U.1
71.9
72.1
75.8
75.7

— ^
5.8
22.6
27.5
U6.8
6U.6
80.1
82.9

__
17.2
73.6
86.1
86.3
88.0
76.6
81.3
                          128

-------
             lOOr-
VO
                         10
20
       30       fcO        50       60        70
           Salt Concentration,  10"1* moles per liter

Figure 52.  Treatment or kraft  decker wastes with bivalent  ions
90
                                                                                                               100
                                                                                      110

-------
  lOOi



   90



   8G



   70
8  50
&
   20



   10
 X Ca(OH);
              10
                                30
     to       50      _ 60       70

Salt Concentration, 10~* moles per liter
80
90
                         Figure 53.  Treatment of kraft caustic  extract with bivalent  ions
                                                                                                   100
                            110

-------
                                             FeCl3-pH unadjusted
100 _
          5
10        15       20 _      25       30
Salt Concentration, 10~" moles per liter
35
        Figure 51* .  Treatment of kraft decker waste with trivalent ions
                                FeCl3-pH adjusted
                                                   FeClj-pH unadjusted
            5  ~     10        15       20 _      25        30        35
                     Salt Concentration, 10~" moles per liter

        Figure  55,  Treatment of kraft  caustic  extract with trivalent  ions
                                                           1*0
                                     131

-------
extract.  An interesting observation is that FeCls removes  more color
from decker when the pH is not adjusted and is on the acid side.   This
situation reverses itself in the case of caustic extract.   It seems
that some decker color is precipitated because of lower pH and is  re-
moved with color-Fe complex.  In the case of caustic, however, because
of higher carboxyl content (see IR investigation, this report) less
color is precipitated at lower pH but is taken out with the "ferric
floe" under alkaline conditions.

The results, in general, show that trivalent ions are more  effective
color removing agents than the bivalent ions and that higher percentage
of color is removed from caustic extract with FeCla under  alkaline con-
ditions.

From the above results "optimum" levels of salt concentrations were
found or in some cases projected over which no significant increase
in color removal was achieved or expected.

Further experiments with metal ions and lime were planned  in which metal
compounds were varied below the established "optimum" addition levels.

TREATMENT OF MILL WASTES WITH VARYING METAL-ION CONCENTRATION
AND CONSTANT LIME CONCENTRATION

Barium chloride and ferric chloride were the two salts used (in conjunc-
tion with lime) in the lime treatment of untreated and lime-treated
caustic extract and NSSC effluents.  Lime-treated effluents contained
color bodies not removed by the conventional one-step lime-treatment
process.  The effluents were used in this study to find out whether  or
not more color can be removed by the metal ion-lime system.  Lime  con-
centrations for these runs were kept at 850-1000 ppm and the metal ions
(as salts) were varied between 25-1500 ppm (ppm unit was used for  easy
understanding, conversion units are given for moles/liter  wherever neces-
sary).  Freeze-dried color bodies from the effluents were  dissolved  in
distilled water to give 0.2 percent solutions, which were  then used  for
this study.
                                   132

-------
Forty milliliters of the above solution were measured into a 100-ml
graduated cylinder, the desired amount of salt solution was added and
the volume brought to the 80-ml mark with distilled water.  Lime slurry
was then added to the above mixture giving a final lime concentration
of 850-1000 ppm.  Mixing was accomplished by inverting the graduates
five times.  The treated effluent was then allowed to stand undisturbed
for a minimum of 15 minutes and the volume of sludge was centrifuging
at 9000 rpm for 15 minutes.  The clear supernatant was carefully poured
off and stored until tested for color.  The percentage of removal of
color was calculated from the data and the results are given in Table
3k.  The results show that at 850 ppm lime, 300 ppm BaCl2 , and 150 ppm
FeCls are reasonably optimum quantities for color removal from the un-
treated caustic extract , whereas in the case of lime-treated caustic
extract only £ 50 ppm BaCla and £ 25 ppm FeCls are sufficient to give
maximum color removal.  (Metal ions should be added before lime addi-
tion. )

In the case of NSSC effluents, however, at 1000 ppm lime the percentage
of color removal generally increases with increasing amounts of salt
concentrations.  It seems that "optimum" concentration was not reached
in the range studied.

TREATMENT OF MILL WASTES WITH VARYING LIME CONCENTRATION
AND CONSTANT METAL ION  CONCENTRATION

In this set of experiments lime concentration was varied  from 300 to
1500 ppm and ferric- and barium chloride were kept constant at concen-
trations set by previous experiment.

Forty milliliters of 0.2 percent effluent was mixed with  the required
amounts of salt solution and lime, the volume was made-up to 80 ml in a
100-ml measuring  cylinder  and the mixture processed and analyzed as be-
fore.  The results are  given in Table  35-
The  data show that FeCla is more effective than BaCla in the case of all
effluents tried.  For example, with untreated caustic extract over 96
percent  color was removed with 150 ppm FeCl3  and  only 300 ppm lime,

                                   133

-------
whereas in the case of BaCl2 > 96 percent removal could be reached at

300 ppm BaClz and 1500 ppm lime.
        Table  3!*.  PERCENT COLOR REMOVAL FROM MILL WASTES BY THE
                          METAL ION-LIME SYSTEM
                   (Lime Concentration Kept Constant)
     Salt
concentration,
     ppm
                       Caustic extract
                       (850 ppm lime)
                      NSSC effluent
                     (1000 ppm lime)
                  Untreated
Li me- treated
                           Untreated
Lime-treated
FeCl3
                    86.0
91.1
93.0
91-7
9»*.8

93.9
91*.9
9U.8
    67.2
                                  >85.
                                  >85.
                                  >85.
                                  >85.
                                  >85-
                                  >85.
                                  >85-
                                  >85.
                                  >85.7
                                                 53.3

                                                 5 8; 5
                                                 56.7
                                                 63.5
                  60.
                  60,
                  62,
                  61*.
                  67.2
    31.9

    37-5
    1*2.8
    1+0.0

    l*o! 8
    53.1*
    59.0
    58.0
0
25
50
75
100
125
150
200
300
86.0
9^.3
95.2
92.5
91*. 9
91*. 5
96.6
96.8
97.8
67.2
>85.7
>85.7
>85.7
>85.7
>85.7
>85.7
>85.7
>85,7
53.5
61*. 1
68.1*
73.0
7!+. 1
73.7
7l*. 3
79.9
80.7
31-9
1*1.3
1*5-9
1*9.2
1*9.2
51.1*
51+.1
5U.5
61.8
BaCl2, 100 ppm = H.8 x 10""1* moles/I.
FeCl3, 100 ppm = 6.2 x 10"" moles/I.


The low figure of 300 ppm lime in combination with 150 ppm FeCl3 is much

lower than the stoichiometric lime requirement of 1000-1500 ppm in the

absence of metal ions.  At this concentration (300 ppm) of lime, how-

ever, the sludge obtained was very light and hard to settle.  Further

exploration showed that good settling sludges were obtained, especially

when FeCla was present, at a minimum lime concentration of about 1000

ppm.  The Table 35 further shows that over 50 percent of the color left
                                   13U

-------
by conventional lime treatment can be removed by using a FeCl3-lime
system.


          Table 35.  PERCENT COLOR REMOVAL FROM MILL WASTES BY
                        THE METAL ION-LIME SYSTEM
                 (Metal Ion Concentration Kept Constant)

     Lime
concentration,
                       Caustic extract
NSSC effluent
ppm

0
300
1*00
500
600
700
800
900
1000
1500

0
300
1*00
500
600
700
800
900
1000
1500
Uh treated
BaCl2 300 ppm
0
91-7
92.6
92.7
93.3
9l*. 1
91*. 6
95-0
9l*. 9
95-9
Fed 3 150 ppm
•^20.00
96.5
97.5
97.8
97.9
98.1
98.3
98.3
98.3
98.3
Lime-treated
100 ppm

1*5.6
1*5.6
1*9.1
52.6
52.6
52.6
1*9. 1
52.6
51*. k
25 ppm

51*. 1*
5U.1*
57-9
5l*.l*
52.6
52.6
50.9
5U.1*
59-7
Untreated
300 ppm

18.6
25-7
27.1*
51.9
53.1
55.7
56.8
62.2
6l.l
200 ppm

1*1.7
58.9
67.0
-—
—
73.1*
71.0
73.3
73.9
Lime-treated
1000 ppm

28.0
29.6
31*. 5
2l*.i
37-9
39-1*
1*2.5
35-9
1*0.9
200 ppm

31.1*
1*7.1
1*0.9
52.7
50.3
57-3
58.8
57.9
1.8.9
BaCl2, 100 ppm = 1*.8 x
FeCl3, 100 ppm = 6.2 x
Lime, 100 ppm = 13. 5
                       lO"*1 moles/1.
                       lo"1* moles/1.
                     x 10~" moles/1.
In the case of NSSC effluent, conventional stoichiometric lime treatment

has been found to remove about 6U percent of the color (see Appendix V) ;

this percentage removal figure can be achieved using about half the stoi-
chiometric lime required with 200 ppm FeCl3.  In this case also over 50
percent color can be removed from the lime-treated effluent.
                                   135

-------
STATISTICAL ANALYSIS (REGRESSION ANALYSIS)

In any system in which variable quantities change, it is of interest to
examine the effects that some variables exert (or appear to exert) on
others.  There may be in fact a simple functional relationship between
variables; but most often the functional relationship which is too com-
plicated to grasp or describe in simple terms.  If this is the case, we
may vish to approximate this functional relationship by some simple
mathematical function, such as a polynomial, which contains the appro-
priate variables and which approximates the true function over some
•limited ranges of the variables involved.  By examination of such a
function we may be able to learn more about the underlying true rela-
tionship and to appreciate the separate and Joint effects produced by
changes in certain important variables.

Even where no sensible physical relationship exists between variables,
Ve may wish to relate them by some mathematical equation.  The equation
may foe physically meaningless, but it may nevertheless be extremely
valuable for predicting the values of some variables from knowledge of
others.  The details of this analysis are given in the experimental part
of this report.

The data obtained by previous experiments (Tables 3^ end 35) were ana-
lyzed using the standard regression analysis techniques.  The results of
the analysis relate the change in percentage of color removed to the
amount of lime and metal ion present.  The three regression equations
obtained are given in their respective tables, 36, 37» and 38.  The
theoretical values of color removal obtained by regression analysis are
plotted against experimental values in Figures 56, 57, and 58-

The data from Table 3^, where metal ion concentration was varied and
lime concentration kept constant, were analyzed to obtain constants
shown in Tables 36 and 37.  Analysis showed that both iron and barium
contribute significantly to the removal of effluent color.  The presence
of the b2 term in both equations indicates slight deviation from a
linear effect.  Lime has a "constant" effect on color removal when iron

                                   136

-------
is present and a "nonconstant"  effect  vhen barium is  present  (because
of the presence of the b3 slope).   In  other words, vhen  barium is used
vith lime, both barium and lime can be added to significantly change the
color removal effect.

       Table 36.  EFFECT OF FERRIC CHLORIDE CONCENTRATION ON  LIME
           TREATMENT OF KRAFT BLEACH EFFLUENTS (CAUSTIC  STAGE)
Model: Percent = b0 -
b .» [lime]2
Regression
terms
bo, %
bi
b2
f bi[FeC!3] + b2[FeC!3]2
Regression
coefficient
92.17
0.0^8388
-0.000097
+ b 3 [lime] +
Standard
error
—
0.005700
0.000052
                bi,
                r
                r
                 2
                  ,
5U.O
       Note:  The regression coefficients bi, ba» b3, b^, give the
              response per unit change in the variable.  In the
              above table terms b3 and bij are not significant.
       bo = Average percentage color removal by FeCl3 over the
            range studied.
       r2 = Percentage total variability of color removal ex-
            plained by the above equation.

 The values labeled r2 indicate the percentages of total variation of
 color  removal which have been explained by the regression equations
 shown.  The lower percentage values  ($b and 60 percent, Tables 36 and
 37, respectively) are not very good  and indicate the existence of
 potentially sizable deviations between predicted and experimental color
 removal values.  The 96 percent value for the model in Table  38 is much
 better.

 The data  from  Table 35, where metal  ion concentration was kept constant
 and lime  concentration varied, were  used to  obtain the constants  shown
 in Table  38.   A dummy variable was introduced  in the  calculations to
 indicate  the different metal  ions present.   Results  showed that  lime has
 a significant  effect  on  color removal and  that  this  effect  is nonlinear.

                                    137

-------
Table 37.  EFFECT OF BARIUM CHLORIDE CONCENTRATION ON LIME
    TREATMENT OF KRAFT BLEACH EFFLUENTS (CAUSTIC STAGE)

Model:  Percent = b0 + bi[BaC!2] + b2[Bad2]2 + b3[lime] +
        b i» [lime]2
Regression
terms
bo, %
bi
b2
bs
Refression
coefficient
89.11
0.007683
-o.oooooi*
0.003208
Standard
error
—
0.003579
0.000002
0.0009M
           :, %            60.0
Note:  The regression coefficients bi, b2, b3, bi,, give the
       response per unit change in the variable.   In the
       above table term bi» is not significant.
bj = Average color removal by BaCl2 over the range studied.
r2 * Percentage total variability of color removal explained
     by the above equation.
 Table 38.  EFFECT OF LIME CONCENTRATION ON COLOR REMOVAL
            WITH CONSTANT LEVELS OF METAL IONS

 Model:  Percent • b0 + bi[lime] + b2[lime]2 + b3[X]

 where X = 0 when FeClj is present, and
         • 1 when Bad2 is present.
Regression
terns
b0
bi
ba
bs
r2
Regression
coefficient
9^.21
0.007599
-0.000003
-U.03
96,0
Standard
error
—
0,000^16
0.000001
0.23

 Note:   The regression coefficients  bi,  ba,  bs,  give  the
        change in response per unit  change in the variable.
 bo  « Average percentage color removal by lime over the
     range studied.
 r2  • Percentage total variability of color  removal ex-
     plained by the  above equation.
                            138

-------
   9.9r-
   9-8
   9-7
£ 9.6
w
 O
O
   9.5
   9-If
   9-3
    9.2
                                     X:  Experimental values
                                  Curve:  Theoretical values by
                                         regression analysis
                                            I
                               10
                         15          20
                        Iron, ppm (x 10')
25
30
35
      Figure 56.
Effect of FeClj concentration on color removal.   Line concentration was
   kept constant.   (Color removal values at 150 ppm FeClj
           from Table kO have also been plotted here)
                                            139

-------
     9.6
    9.52
2
£   9.36
 I
 <*   9.28
     9.2
    9.12
                                                *  Experimental  values
                                             Curve: Theoretical values by
                                                   regression analysis
    9.0lt
                                             I
                                                          I
                                 8           12          16
                                          Barium, ppm (x 102)
                                               20
28
          Figure 57.
Effect of BaCl2 concentration on color removal.  Lime concentration vas
 kept constant.  (Color removal values at 300 ppm BaClz from
           Table ^0 have also been plotted here)
                                              li*0

-------
9.8
                           x
                           o
           Q

     5?     x     x

  Ferric chloride, 150 ppm
9-7
9-6
3
^
**

-------
The presence of bs constant indicates that the use of barium in place of
iron will result in a loss of h percentage units of color removal.

The analysis of the data suggested that iron is a more effective color-
removing agent than barium in the lime treatment of mill effluents  (Fig-
ure 58)-  The analysis shows that when the amount of iron is held con-
stant and lime varied, a good estimate of the effect of lime can be made.

Figures 56 and 57 show large deviation from the regression curve (theo-
retical curve) and suggest that when discussing the expected percentage
color removal due to either metal ions, a range would be more useful
than a definite prediction.

To provide information about the independence of the effect of the  two
additives (lime and iron) it was thought that a series be run in which
the amounts of both iron and lime be varied.

TREATMENT OF MILL EFFLUENT WITH VARYING LIME AND FeCl3

Designed experiments were performed to study the effect of lime treat-
ment on kraft bleach effluent in the presence of metal ions (FeCla).
The purpose of this study was to determine the effect of these additives
on the amount of color removed from the effluent samples, and also  to
determine whether or not the effects of the two additives are indepen-
dent of each other.  The following levels of additives were studied.
                      Lime, ppm: 1000, 2000, 18,000
           FeCl3, ppm: 0, 25, 50, 100, 200, 300, 500, 800

The levels of each variable were run once with all levels of the other,
giving a total of twenty four experiments.  The results obtained are
given in Table 39.

The effect of FeCl3 on sludge volume at different levels of lime is
depicted in Figure 59-  Lime concentrations of 1000 and 18,000 ppm  and
FeCla concentration of more than 100 ppm give denser sludges than those
at 2000 ppm.   In fact, sludge obtained at 18,000 ppm lime is the most
dense indicating better settling properties.

-------
Table 39.  LIME TREATMENT OF KRAFT BLEACH CAUSTIC EXTRACT IN THE PRESENCE OF METAL ION
Experiment
no.
FeCl3,
ppm
Lime,
ppm
Sludge vol. , Final
ml pH
Untreated caustic extract
1
2
3
U
5
6
7
8
1
2
3
1*
5
6
7
8
1
2
3
U
5
6
7
8
0
25
50
100
200
300
500
800
0
25
50
100
200
300
500
800
0
25
50
100
200
300
500
800
1,000
1,000
1,000
1,000
1,000
1,000
1,000
1,000
2,000
2,000
2,000
2,000
2,000
2,000
2,000
2,000
18,000
18,000
18,000
18,000
18,000
18,000
18,000
18,000
6.2
8.2
8.2
8.5
13.3
11*. 1*
22.0
30.1
6.2
7.0
7-3
9-7
ll*.l
19-1
33.5
62.0
8.9
8.7
9.0
9.1*
11.2
12.2
U*. 3
16.8
8.83
11.58
11.50
11.1*2
11. U2
11.1*9
11.50
11.1*0
11.32
11.79
11.70
11.70
11.70
11.70
11.71
11.78
11.73
11.98
11.99
11.98
12.00
12.01
12.01
12.01
12.00
Color
units
1*»397
820
806
627
1*1*0
377
370
186
196
561
528
U62
361
291*
209
11*1
111
292
226
220
180
162
119
80
58
Ah sorb an ce ,
280 run U80 nm
9.1*5
2.53
2.57
2.20
1.60
1.1*2
1.1*1*
0.81
0.8U
2.00
1.83
1.7U
1.1*2
1.10
0.97
0.70
0.50
1.01
0.97
0.87
0.82
0.68
0.51
0.1*0
0.31*
2.12
0.38
0.36
0.32
0.19
0.19
0.21
0.09
0.09
0.29
0.23
0.25
0.20
0.13
0.12
0.10
0.05
0.15
O.lU
0.11
0.09
0.06
O.Ol*
o.oU
0.02
TOC,
mg/1
220
73.5
7l+. 5
63.8
1*8.3
52.0
56.5
1*2.0
37.8
69.0
51*. o
59.5
51*. 5
UU.S
1*0.5
30.8
28.0
U3.0
1*5.0
1*9.3
1*0.3
35.0
Uo.8
27.0
2U. 8
BOD,
mg/1
1^*7
UU
1*5
1*7
1*1
36
31*
30
28
36
36
35
33
31
30
26
23
32
32
29
30
30
25
25
23

-------
I
r-l
CO
                                                                                  ,D

                                                                          Lime '
                                                                             /2.000 ppm
                                                                       	A
                                                                             18,000
                                                               606
700
 100      200        300Voo       500
                          Fed 3, ppm

Figure 59.   Effect of ferric chloride  and lime  on sludge volume

-------
The percentage color removal based on results in Table 39 are  given  as
"actual" data in Table UO.   The data in Table Uo were analyzed using
standard regression analysis techniques similar to the one used earlier.
The regression equation which was obtained from the data in Table Uo
is given in Table Ul.  The last term (bs) in the regression equation in-
dicates a lack of independence between lime and the metal ions and their
effect upon the color removal.  In other words, it cannot be predicted
how much color one may remove by adding 500 ppm FeCl3 without knowing
how much lime will be added also.  This fact has also been demonstrated
by Figure 60.  Had the effect of these two variables been independent,
all curves would have shown similar trends and slopes.

             Table 1*0.  PERCENT COLOR REMOVAL By LIME iw THE
                         PRESENCE OF METAL IONS
FeCl3
concentration
ppm
0
25
50
100
200
300
500
800
"Experimental
Limp concentration , ppm
1000
actual a
81. U
81.T
85-7
90.0
91. U
91.6
95-8
95-5
values.

calb
83.8
8U.7
85.5
87.1
89.8
92.0
9U.8
95. ^
LC- c" -i r\n a
2000
actual8-
87-2
88.0
89.5
91.8
93.6
95-2
96.8
97.5
nnl VST s .

cal
87.3
88.1
88.9
90.5
93.1
95.2
98.0
98. U

16,000
actual
93. 1+
9U.9
95.0
95-9
96,3
97.3
98.2
98.7


cal
93.3
93-9
9U.5
95-5
97.3
98.5
99.5
97.2

 Using the regression equation (Table Ul) and the actual levels of addi-
 tives, the "calculated" percentage color removal values are obtained
 (see Table Uo).  The agreement between the actual and the calculated
 data is extremely good for all levels (Figure 6l).  The correlation for
                                    1U5

-------
 this  equation,  i.e., the percentage variation, r2, in color removal ex-
 plained by the  regression is 93$  (Table 1*1).

      Table 1*1.  EFFECT OF VARYING LIME AND METAL ION CONCENTRATION
                ON COLOR REMOVAL  (REGRESSION EQUATION)
Model: Percent =
bjlime]2
Regression
terms
bo
bi
- b2
U 3
D li
bs
r2
bo + bj[FeCl3] = b2[FeC!3]2 + b3[lime] +
+ bs[FeCl3][lime]
Regression Standard
coefficient error
80.05
35.03
-0.025
3.99
-0.0001809
-0.0005991*
93.0

x 10" 3
x 10" 3
x 10" 3
x 10" 3
x 10~3

—
U.239
0.0051^
0.882U
O.OOOOU5
0.000150


x 10" 3
x 10- 3
x 10" 3
x 10~3
0
x 10

     Note:  The regression coefficients bi, b2, b3, bi», bs, give
            the change in the response per unit changes in variable.
     bo = Average percentage color removal over the range studied.
     r2 = Percentage total variability of color removal explained
          by the above equation.

A comparison of regression coefficients obtained earlier (Tables 36 and
37) and now (Table Ul) is made in Table U2.  This table shows that with
the exception of the constant for the quadratic effects, the regression
coefficients of the present work are in line with those obtained in the
earlier work.   The linear terms for both lime and FeCl3 are within the
statistical limits of acceptability.  The changes in the quadratic terms,
however, would seem to be due to the presence of_ the interaction of FeCl3
and lime.

Similar experiments run on the lime-treated caustic extract as run on
the untreated caustic extract (see Table 39) indicated that over 80 per-
cent of the color, which was left by conventional lime treatment process,
can be removed using 500 ppm FeCl3 and 1000 ppm lime.   At lower FeCl3
concentrations (less than 150 ppm) and 1000 ppm lime only, 65-70 percent
color was removed.

-------
10.8 r~
 8.0
                                        6            8          10
                               Iron Concentration, ppo (x 102)
        Figure 60.  The interactive behavior of line and metal ions on color removal

-------
    90
    80
                         8        8                  i                           8

        Q9    ™                                 Lime «  18,000 ppm
ll

O
s
I
KnL.
        I!*
   1001-
                          O  Actual

                          D  Calculated
   ioor

                                  a
                        g                               2,000
    go L                       •  Actual

                              D  Calculated
90
I
1
80
8
!• i i
3 100 200
8
i i
300 UO
fi
1,000
1 1
0 500 600
1 1
700 800
                                       Fed 3,  ppm


     Figure  61  Percentage of  color  removal  by  lime  in  the  presence of metal  ions

-------
           Table U2.   COMPARISON OF REGRESSION COEFFICIENTS
                                      Regression coefficients
                              From Tables 35, 36     From Table
     Linear FeCl3, ppm            1+8.39 x 10~3        35-03 x 10~3
     Linear lime, ppm              7.60 x 10~3         3.99 x 10~3
     Quadratic FeCl3, ppm        -0,097 x 10~3       -0.025 x 10~3
     Quadratic lime, ppm         -0.003 x 10~3    -O.OOOlSl x 10~3
     Interaction8", ppm                -NA-         -0.00056 x 10~3
     NA = not available.
     ft.
      Interaction of Fed3 and lime.

The statistical analysis suggested that iron is a more effective color-
removing agent than barium in the lime treatment of mill effluent.
This study further suggests that some interaction between lime and
FeCls is present resulting in better color removal then when either
of the two is used separately.  In other words a "synergistic" effect
exists.
                                   11*9

-------
                               SECTION VII

                              EXPERIMENTAL

PROCESSING AND FREEZE-DRYIWG OF WASTES

Untreated and lime-treated colored samples were  concentrated under re-
duced pressure to one-tenth of their original volume.   (Untreated
samples, if concentrated further, were very difficult  to freeze-dry.)
Most of the calcium, especially in the lime-treated samples,  was pre-
cipitated by carbonating the samples to a pH of  10.2.   The  carbonated
samples were then centrifuged in the beta-centrifuge at 9000  rpm for 15
minutes.  This speed and time was sufficient to  give clear  solutions.
If, in some cases, slight turbidity was still present,  these  samples
were filtered through a Millipore filter paper.   The pH of  the  solution
was checked at every stage.  The colored but clear solutions  were frozen
in strong glass containers (centrifuge bottles)  and dried, under high
vacuum.  This freeze-dried material formed a low density powder and was
readily soluble in water.  The dried samples could be  kept  in airtight
bottles for longer periods without any significant change.

ISOLATION OF ACID-INSOLUBLE COLOR BODIES

Freeze-dried solids of the untreated waste (lU.3 g od  basis)  were dis-
solved under mechanical stirring in 60 ml of water and approximately 17
g of clean cellulose powder (Whatman standard grade) was suspended in
the solution.  The stirring was continued and the pH was adjusted to
1.0 with strong hydrochloric acid (l vol. concentrated acid to  2 vol. of
distilled water).  The acidified mixture was filtered  through a precoat
of about h g of  cellulose powder on a Buchner funnel and the filter cake
was washed with  a total of 50 ml of water in small portions.  When the
filtrate was just acid to Congo Red paper, some of the precipitate pep-
tized and formed a cloudy filtrate.  The cloudy filtrate was mixed with
about 3 g of acid-washed Fibra-Flo 11C  (Johns-Manvilie filter aid),  the
mixture was filtered on a thin precoat  of Fibra-Flo on a small Buchner
funnel, and the  filter cake was washed with water.
                                   151

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 Both the  cellulose powder and  the Fibra-Flo  filter cakes vere separately
 extracted with  50 percent aqueous ethanol.   The  alcohol was evaporated
 from the  combined solution at  reduced pressure whereupon a finely divid-
 ed precipitate  formed; the slurry containing this precipitate was subse-
 quently freeze-dried, and designated  as  "acid-insolubles,"  The aqueous
 filtrate  contained the "acid-soluble" material.

 ISOLATION OF ACID-SOLUBLE COLOR BODIES

 The acid-soluble fractions  obtained during acidification of mill wastes
 were recovered  and fractionated using Rohm & Haas Co.'s Amberlite XAD-8
 resin (polystyrene cross-linked with  divinyl benzene).

 The acid-soluble solutions were first passed through  a 2*K) ml bed of
 Amberlite XAD-8 resin.  The column was eluted first with water and then
 with aqueous ethanol (l:l water — 95  percent ethanol  mixture).  The
 eluate was actually collected  in seven fractions but  the last four
 fractions (eluted with aqueous ethanol) were combined to give four final
 fractions.  Each fraction was made alkaline with sodium hydroxide to pH
 about 9^0 (ethanol was removed under  reduced pressure).

 The first fraction contained material which passed through the column
 (unadsorbed) with the original solution.  A floe similar to that of fer-
 ric hydroxide was noticed when this fraction was made alkaline, and the
 floe was  separated by filtration.

 The second fraction contained material which was held on the column
 initially, but was readily eluted from the column with water.   Upon
 alkalization this fraction deepened in color and was more highly colored
 than the  first  fraction.

 The  third fraction was an intermediate fraction and was collected until
 the  eluate was neutral to Congo Red.

 The  fourth and the final fraction contained material eluted with aqueous
ethanol.
                                   152

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It should "be kept in mind that the fractionation  was  not  sharp,  and thus
each fraction could contain some material similar to  that found  in  the
previous fraction.

FRACTIONATION OF COLOR BODIES

Two types of Bio-Gels (Bio Had Co.) were used for this purpose.   Bio-
Gel P-2 (exclusion limit 2600) and P-60 (exclusion limit  60,000) were
hydrated in distilled water and separately packed in  2.5  x 200 cm and
2.5 x 100 cm glass columns, respectively.  The complete apparatus used
for fractionation is shown in Figure 62.

The volume of the solutions used for fractionation was less than 3 per-
cent of the void volume of the column (void volume, Vo, = total  bed
volume x 0.38).  A measured quantity of the solution was added to the
top of the column.  A glass fiber filter was used on the gel so that
upon addition of the solution, the gel surface was not disturbed.  The
eluate was allowed to flow into an automatic collecting  device and the
collector timer and the UV-cord recorder were started.  When the solu-
tion dropped to just below the surface of the gel, one milliliter of
distilled water was added to  the  column and elution  continued.  When
the level was again slightly  below the gel, more distilled water was
added and the column was  then connected to the constant  head water
reservoir through a filter and a  flowmeter.  The elution rate (0.2-0.3
ml/min) was  controlled by a teflon stopcock with a needle adjust.  Frac-
tions were  collected every 30 minutes.  At the end of fractionation,
which took  three  to four days,  the collected fractions were combined
according to the  number  of peaks  on the UV recorded  chart.  The  combined
fractions were  freeze-dried  and used  for  study.  (Aliquots of the
fractions were  taken for color, TOC,  and  absorbance  before freeze  dry-
ing. )

COLOR MEASUREMENT

Color was measured according to the platinum  cobalt  standard  method of
the American Public Health Associaliion (APHA)18.   The only modification
of the  method was the  use of a norvcarbonate buffer for pH adjustment  to
                                    153

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       30 cm  Head
 50
                                      Approx.  Scale!  I mm1 I cm
                                  i- Water  Reservoir
       50 cm
      100 cm
                               Filter
                               Flowmeter
                     •Bio-Gel Chromatographic Columns
                             Coupling  w/Teflon Solv-Seal
               — 2.5  cm  I.D.
                 Teflon
                 Needle
                 Valve
                                         UVI-Cortl Monitor
                                         UVI-Cord Recorder
                                                Automatic  Collector
                 Teflon  Stopcock
                 w/Needle  Adjust
Figure 62.  Diagram of Gel Permeation Chromatography Apparatus

-------
7.6.  It was necessary to have color values at a constant pH of 7.6,
because color was found to be pH dependent.  Most natural waters have  a
pH range close to 7«6.

It should be noted that the color unit is a measure of color intensity.
When it has been necessary to refer to the total amount of colored mate-
rial in a solution this has been called "total color" and is the product
of the color units and the volume of the solution.

ABSORBANCE MEASUREMENT

The samples used for color measurement were also used for absorbance
measurement at desired wavelengths on the Beckman DU Spectrophotometer.
The values obtained were multiplied by the dilution factor to give
absorbance of the concentrated solutions.  Absorptivity was calculated
by dividing the absorbance values by concentration in grams per liter.

DETERMINATION OF SOLIDS

Total solids were determined by evaporation of a measured volume of waste
at 105°C overnight.  The resultant weight  of solids was expressed in  mil-
ligrams per liter (mg/l) of waste.

Fixed and volatile solids were determined by igniting the total solids
at 600°C in an electric muffle furnace to  constant weight, usually re-
quiring one hour.  The loss on ignition  is reported as mg/l volatile
and the residue as mg/l fixed solids.

METHOXJfL CONTENT

Methoxyl content was  determined by TAPPI Method T 2 m-60.

PHENOLIC HYDROXTL CONTENT

Phenolic hydroxyls content was determined  by the  Goldschmid method19
using ultraviolet spectrophotometry.
                                    155

-------
TOTAL ORGANIC CARBON (TOG)

The Process Carbonaceous Analyzer (Bechman and Co.) was used for this
purpose.  Because this instrument gives only total carbon, it was modi-
fied to give TOG by the indirect method.

Based on new TOC analyzers, one combustion tube was filled with Quartz
beads saturated with concentrated phosphoric acid.  Total inorganic car-
bon was first estimated by injecting samples in the HsPO^-combustion
tube at 175°C.  This tube was then replaced by the regular combustion
tube containing the catalyst and total carbon was estimated by injecting
samples in catalyst-tube at 950°C.  The difference between total carbon
and total inorganic carbon gave TOC.

Twenty-three microliters of the specimens were injected at 3 to 5-
minute intervals and an average reading was thus obtained from which
the "blank" reading was subtracted to give the TOC value in mg/1.

The "blank" consisted of all the ingredients listed above minus the
sample and was handled in the same manner as the sample.

In addition to the precautions listed in the operating manual, the fol-
lowing precautions are recommended for accurate results.

     a.   The injection syringe should be checked often for burrs,
         cracks, etc. , which cause particles from the rubber cap
         to drop into the combustion tube thus giving high readings.
     b.   A constant slow needle insertion and retraction is essen-
         tial to prevent "popping" of the combustion chamber rubber
         cap.
     c.   Combustion chamber rubber cap should be replaced often.
     d.   Tygon tubing close to the condenser, filters, and glass
         combustion chamber dome should be cleaned often.

DETERMINATION OF MOLECULAR WEIGHTS

Due to large number of samples to be analyzed, the "conventional sedimen-
tation equilibrium method"11* was considered impractical and the "short
                                   156

-------
column sedimentation equilibrium method" was  used.  An  effective way  to
reduce operating times is to shorten the fluid column in the  centrifuge
cell.  In the "short column method" samples columns are 1 mm  or less
compared to 3 mm of the "conventional method."  The time for  equilibrium
was reduced from 2^ hours to 3 hours by using the 1-mm  column.

Although providing the time advantage as well as simplified computations5
"short columns" result in only single value for molecular weight and
thus little information concerning the polydispersity or nonideality
is available.  The values obtained are apparent weight  average molecular
weights for polydisperse solutes.  Normally this procedure has  a pre-
cision of about 3 percent; hpwever, for most of this  work especially  due
to low molecular weights of most samples, the precision is probably much
lower.

For calculation of molecular weights the quantity required from the
equilibrium run is the concentration gradient at the  midpoint of the
solution column usually obtained directly from schlieren patterns.  How-
ever, at the higher concentrations required for schlieren optics,  the
colored solutions resulted in photos which were not measurable.  The
more sensitive interference optical system allowed use  of less  concen-
trated solutions with less color and provided reasonably clear  fringe
patterns.  In this case, the slope of the interference  fringes  at  the
midpoint of the solution column is the concentration  gradient.  It is
assumed, in this method, that the solute concentration  at the midpoint
is equal to the initial concentration.  The initial concentration  must
also be determined.  This is done in a separate centrifuge run  measuring
the total fringe shift  (fringe number) across a synthetically formed
boundary.  Sample concentrations were normally 0.2 percent (in  h^O) al-
though a few were run at 0.1 percent due to color problems.  Solutions
prepared from freeze-dried samples were adjusted to pH 9.0-9.5.   Equil-
ibrium runs were made in a 6-channel cell which accommodates three
samples per run.

The densities of the solutions were measured according to the method de-
scribed by Bauer20 and plotted against their respective  concentrations
                                   157

-------
 in  g/ml.  A straight-line plot was developed and the partial specific
 volume, V, was calculated from the straight-line relationship using the
 Equation
                        V = ^- -  [(-)] (d " d°  )
                        V   do    LVJ l  do    '
 where
     x  = concentration, g/ml
     do = density of solvent
     d  = density of solution.

 The calculations were made by the following equations and a computer
 program (SHOCOL) was written to handle the raw  data.
                          (l-vp)w2  mid  o    mid
     m    = molecular weight
     R    = 8.31^ x 10 7 (Universal gas constant)
     T_    =303 (temperature)
     v    = partial specific volume
     p    = solution density
     r  . , = radial distance to solution midpoint, cm
     c    = initial solution concentration
     dc
    ( — )    = concentration gradient at solution midpoint
     dr mid
     0)    = angular velocity, radians per second.

The initial rotor speed in all runs was 1*2,01*0 rpm which is near the
recommended maximum speed for the 6 channel cell.  After equilibrium
was achieved (usually less than 3 hours) a photograph was taken and the
rotot speed was reduced to 3 lower speeds allowing time for equilibrium
to be reached at each rpm.  The analysis then results in apparent molec-
ular weights (Mw) at each of k rotor speeds for each sample.

Plots were then made of 1/M^ versus angular velocity with linear extrap-
olation to w2 = 0.  Comparisons in molecular weights could then be made
with the effect of rotor speed eliminated.
In most cases the plots had only a slight slope.  However, for some
fractions, especially AI, M^ were highly dependent on to2, apparentlj
due to solute polydispersity.  The much higher M^ (at u>2 = 0) for A;

                                   158

-------
fractions in general were confirmed by analysis of the photographs by
the conventional equilibrium method.  An extension of this procedure
would be to run each sample as described at several concentrations and
plot I/My, at w2 = 0 versus concentration to eliminate concentration
effects also.

REGRESSION ANALYSIS21

The analysis was performed to study the effect  of one variable on  other
as per example given below:
                                                       »
Linear Regression, Case Problem

Let us assume that the regression line (the mathematical equation) of
a variable Y on a variable X has the form 30 + 61 X.  Then we can  write
the linear, first order model
                           Y = g  + BiX + e                         (1)
That is, for a given X, a corresponding observation Y consists of the
value B0 + 3iX plus an amount e, the increment by which an individual
Y may fall off the regression line.

Equation (l) is the model of what we believe.  We begin by assuming
that it holds; we will inquire later if it does hold.  $0 and Bi are
called the parameters of the model.  When we say that a model is linear
or nonlinear, we are referring to the linearity or nonlinearity in the
parameters.  The value of the highest power of an independent variable
in the model is called the order of the model.  For example
                        Y = B0 + B:X + Bi^X2  + e                  (2)

is a second-order (in X) linear (in the B's) regression model.

The values Bo> Bi» and e are unknown in Equation (l) and in fact e would
be difficult to discover since it changes for each observation Y.  (30
and Bi however remain fixed.  Although we cannot find them exactly with-
out examining all possible occurrences of Y and X, we can use informa-
tion from an experiment in which we measure a subset of the values, and

                                   159

-------
obtain estimates, bQ and bi of 3O and 81 •   We then can vrite
                              Y1 = b0 + biX                        (3)
where Y1 denotes the predicted value of Y  for a given X.   Equation  (3)
is then used as a predictive equation; substitution for a value  of  X
would provide an estimate of the true mean value of Y for that X.

Linear Regression, Solution

Suppose we have available n sets of observations (Xi, YI), (Xa,  Y2),  •••»
   , Yn).  Then we can write [from Equation (l)]
The sum of squares of the deviations from the true line  is
                      S - Z6i2 = ZfYj - B0 - Bi^)2                (5)
We will choose our estimates bQ and bi  to be values which when  substi-
tuted for $0 and 3i in Equation (5) produce a minimum value  of  S.  We
determine bQ and bi by differentiating  Equation (5) first with  respect
to 30 and then with respect to 3i and setting the result equal  to zero.
We have then

                        o
                      3S  _. _,„  _ e     B   }                   (?)
                                      0
Substitution of bo and bi for 3O and 3i then gives  the following equa-
tions to solve
                               - b0 - b^)  * 0                    (8)
                               - b0 - b^JXi = 0                  (9)
Rearranging the terms and collecting them into a computable  form gives
the following as solutions for bQ and bj

                          ,     nZXY - (£X)(ZY)
                          bl  "  nZX' -
                          b0 = (EY - bi  ZX)/n                       (ll)

                                   160

-------
(The subscripts  have been  eliminated since all n observations are -used
in the summations.)  Substitution of Equation (ll) into Equation (3)
and rearranging  terms  gives
                          Y'  =  Y + bj  (X - X)                      (12)
If we subtract each  side of  Equation  (12) from the observation (Y)  it-
self we have
                       Y - Y1  =  Y - Y  - bi  (X - X)                  (13)
Summation over all of  the n  observations yields
                    E(Y - Y1)  =  Z(Y -  Y) - b! £(X -  X)              (lU)
Since both terms of the right-hand side equal zero,  we  have  that the  sum
of the residuals (observation minus prediction)  is equal  to  zero,  i.e.,
the deviations are minimum.

Linear Regression, Precision

The precision of the regression line  (and the validity  of our original
assumption) is determined from the identity:
                      Yi - V = ^ - Y - (Y./  - Y)

If we square both sides of the identity and sum over all observations it
can be shown that
                 1^ - Y)2 = E(Yi - Y^)2 + Z(Yi' - Y)2            (15)
and note that the left-hand side of Equation (15) is the sums of squares
of  deviations of the  observations from the mean.  The first term on the
right-hand side is the  sum of squares  of the deviations of the observa-
tions from their predictions; and the  second term is the sum of squares
of  the  deviations of  the predictions from the mean we can write Equation
 (15)  in words as follows:
      Sum  of squares   _  Sum of  squares   +  Sum of squares
      about the  mean     about regression     due to regression
 This  shows that  some  of the variation  can be ascribed to the regression
 line  and  some to the  fact that  the actual values  do not  all lie on the
                                   161

-------
regression line.  We assess the usefulness of the regression line or; u
predictor by comparing how much of the SS about the mean fulls into tho
SS due to regression against the amount that falls into the CS about
the regression.  The ratio r2 is computed as
                         2 _ SS due to regression
                        r  ~ SS about the mean

and we note that when r2 = 1, we have no deviations of predictions from
their observations; when r2 = 0, we have that the regression equation
is useless in its present form.

Multiple Linear Regression —
The usual situation encountered is not that of a response and one inde-
pendent variable.  In many cases it is known beforehand that a response
is dependent upon several variables.  We require information about the
type of relationship (positive, inverse, curvilinear, etc.)s the magni-
tude of the dependence, and the interactions of the independent variables
with the response.

Let us assume that we have three independent variables, Xi, Xa , and Xa
and the response Y, and we have data from an experiment designed to in-
sure independent estimates of the parameters .  If we assume the model
           Y = 60 + BiXi + 02X2 + 63X3 + 3i,2XiX2 + $1,3X1X3
              + 62,3X2X3 + Bi.iXi2 + 02,2X22 + 63,3X3* + e
and obtain estimates b^ of the 3^ as described previously.  The solution
is obtained by solving simultaneous linear equations which result from
differentiating the Function S [Equation (5)3 under our present assump-
tions.  A statistical test is made for each of the parameters to deter-
mine whether the parameter is equal to zero (i.e., no effect) or not
equal to zero.
The interpretation of the bA and bj^ parameters is straightforward.  The
"interaction" parameters , bij , is testing the independence of the effect
of the variables "i" and "j" upon the response.  If it is found that a

                                   162

-------
Injector:
Column:
parameter b^ j is not equal to zero, it implies the effect is dependent
upon the levels of the two variables.

PYROLYSIS-GAS LIQUID CHROMATOGRAPHY

The Varian Aerographs lUOO series gas chromatograph vas used for this
purpose.  Selected samples of freeze-dried color bodies from dilute
waste liquors were subjected to pyrolysis-gas liquid chromatography
(GLC).  The conditions were as follows:

Pyrolysis:   Hamilton Multi-Purpose Sampling System
             Furnace temp, UOO°C
             Oven zone temp, 2l*0-2U5°C
             Heated line temp, 2UO-260°C
             190-200°C
             10 percent Carbowax 20M; 5 ft x 1/8 inch
             Initial temp, 75°C
             Final temp, 200°C
             Rate, Wmin
             Hydrogen flame ionization
             Temp, 275-285°C
Gas sources: Carrier gas:  He at 75 ml/min
             Hydrogen:  Varian Aerograph Model 9652 Hydrogen Generator
             Air:  Cylinder
Sample size: Sample weights could not be kept constant due to differ-
             ences in ash contents.  Most of the samples were not
             weighed for this qualitative study.

Modular Construction

The Hamilton Multi-Purpose Sampling System consists of temperature con-
trol unit,  a gas control unit, a furnace assembly, a heated line and
miscellaneous parts and supply.

The temperature control unit supplies  adjustable power to the Furnace
Assembly  and Heated line.  It also provides thermocouple meter  read-out
Detector!
                                   163

-------
of temperature at two points in the Furnace Assembly and at one point
in the Heated Line.

The gas control unit provides means for diverting carrier gas through
the Furnace Assembly to flush sample vapors into the inlet of the gas
chromatograph by way of the Heated Line and its terminal needle.

The Furnace Assembly includes a tubular Vycor chamber in which the
sample is processed.  This processing tube passes through three zones
of Furnace Assembly:

      (l)  A room temperature zone, where the sample may be
          held while purging air from the system,
      (2)  a furnace zone, capable of 800°C, into which the
          sample is dropped for heating,
      (3)  an oven zone, which heats to 300°C for vapor
          holding.  After passing through the oven, the
          processing tube connects directly with the
          heated line.

The Heated Line operates at temperatures up to 300°C and has only stain-
less steel in contact with the sample.  It is quite flexible, to allow
insertion of its terminal needle into the chromatograph inlet.  Accord-
ing to the Hamilton manual the insulation on Heated lane should permit
safe handling at high temperatures.  Our experience showed, however,
that the Line could not be handled with bare hands.

Sample Handling

Samples are usually contained in thin-wall quartz sample tubes during
processing.  One purpose of the sample tube is to facilitate determi-
nation of initial sample weight and weight of residuals after pyrolysis.
Another purpose is to insure that all forms of sample —powders, liquids,
etc.  — drop into the furnace in an identical manner, to the same spot,
and are exposed to identical conditions.  The sample also protects the
processing tube from direct contact with other than sample vapors, thus
lengthening the time between cleanings,

-------
The best method of retaining samples  is  to use small plugs of woven
quartz fiber yarn or quartz wool.

Quartz tubes and loosely "wadded"  quartz wool were  fired in a muffle
oven at 800°C until clean (usually 15 minutes were  enough) and cooled
in a desiccator.  Sample tubes  and quartz wool were handled with tweez-
ers to avoid contamination by body oils. Samples were  loaded in the
tubes as follows:

     (l)  Sample tube was plugged on  one side with  the  wadded
          quartz wool.
     (2)  The tube was held with clean  tweezers  and the solid
          sample was loaded through a small funnel  made out of
          aluminum foil, solvent cleaned on the  side  that
          contacts the sample.   The open end of  the filled
          tube was then plugged with quartz wool as before.
          The pltigs were dense enough to prevent the  sample
          grains from falling.
     (3)  In case of low density powders, the open end of the
          sample tube was inverted on the sample and pushed,
          turned upright and tapped on  the plugged end for the
          sample to fall in the tube.  In some cases, clean
          needles were used to push the sample to the middle
          of the tube before plugging the open end.
     (k)  Care was taken to ensure that no grains were left
          on the outside of the sample tube.
     (5)  The liquid  samples were injected with a microliter
          syringe  onto  the quartz packing, allowing capillary
          action to retain the sample.

 Sample tubes  (filled) were  inserted  into the processing tube through the
 sample port and the  cap was  screwed  in  (sample introduction knob was on
 "on" position and  the gas  flow had "been adjusted to 75 ml/min with the
 help of flow balance  adjust).  The furnace assembly was tipped to drop
 the sample  tube onto  the quartz wool plug in the furnace  zone, lowered
 back to horizontal position, latched in place and  the  GLC column oven
 linear temperature program and recorder chart were started.
                                   165

-------
                              SECTION VIII


                               REFERENCES


 1.   National Council  of the  Pulp  & Paper Industry  for  Mr  and Stream
     Improvement  (NCASl).   Tech. Bull.  No.  157,  Dec.  1962.

 2.   Le Compte,  A.  R.   Tappi.   1*9(12) :121A, 1966.

 3.   Berger,  H.  F.  and R.  I.  Brown.  Tappi. U2(3):2l+5,  March  1959.

 U.   Smith,  D.  R.  and  H. F. Berger.  Tappi.  5l(lO):37A,  Oct. 1968.

 5.   Davis,  C.  L. ,  Jr.   Tappi.  52(ll):2132, Nov.  1969.

 6.   Spruill, E.  L.  Water and Sewage Works.  Industrial  Waste Supple-
     ment.   118:15, 1971.

 7.   Information from  Humphrey, J. E.   Project Director,  International
     Paper Company, Springhill, La.

 8.   Dence,  C. , et_ al.   NCASI Tech. Bull. 239, 1970.

 9.   Dugal,  H.  S., et_ al.  EPA Report No. EPA-R2-73-11*!,  February 1973.

10.   Swanson, J, W., H. S. Dugal,  M. A. Buchanan, and E.  E. Dickey.
     Effluent Color Characterization Before and After Stoichiometric
     Lime Treatment.   Environ. Protection Agency, Washington, D.C.
     Publication No. EPA-R2-73-086.  February 1973-  75 p.

11.   Schachman, H.  K.   Reprint from Methods in Enzymology.   Vol  IV.
     Academic Press Inc., New York, N.Y., 1957-

12.   Goldschmid, L. 0.  In_ Sarkanen and Ludvig's Lignins  Occurrence,
     Formation, Structure and Reactions. New York, Wiley Interscience,
     1971.  p. 256-258.

13.   Goring, D. A. I.   Chromophore Seminar, Raleigh, N.C.,  April 1972.

Ik.   Chervenka, C. H.   A manual of Methods  for the Ultracentrifuge.
     Beckman Instruments Inc., 1969.  P- ^2-55.

15.   Ortiz, De Serra,  and Schnitzen's Soil.  Biol. BioChem. 5(3):28l-
     286, 1973.

16.   Supplied by Fleck, J.  PhD Student.   The Institute of Paper
     Chemistry, 1973.

17.   Personal communication.   Spruill, E.  L., Supervisor, Environmental
     Control, Continental  Can Co., Hodge,  La.

                                    167

-------
18.  Standard Methods.  American Public Health Association (APHA).
     12th ed., 1965.  p. 129.

19.  Goldschmid, 0.  Anal. Chem, 26(9):ltel, 195^.

20.  Bauer, N.   Determination of Density.  In_ Weissberger's Tech-
     nique of Organic Chemistry.  Physical Methods.  2nd ed.   Vol.
     1.   Part 1.  Interscience, New York, 19^9.  p. 25U-296.

21.  Draper, N. R., and Smith, H., Applied Regression Analysis, John
     Wiley & Sons,  New York, 1966.
                                   168

-------
                               SECTION IX

                               APPENDICES
                                                                        Page
  I.   Fractionation of Color Bodies from IPCO's Kraft Decker Effluent:
      Massive Lime Treatment                                         '    170
 II.   Sugar Analysis of Decker, Caustic Extract, and NSSC Wastes from
      Massive and Stoichiometric Lime Treatment                          171
III.   Fractionation of Color Bodies from IPCO's Kraft Bleach Caustic
      Extract:  Massive Lime Treatment                                   172
 IV.   Fractionation of Color Bodies from CONGO'S Kraft Decker Effluent:
      Stoichiometric Lime Treatment                                      173
  V.   Fractionation of Color Bodies from CONGO'S NSSC Effluent:  Stoi-
      chiometric Lime Treatment                                          17**
                                    169

-------
                                      APPENDIX I
            FRACTIONATION OF COLOR BODIES FROM IPCO'S KRAFT DECKER EFFLUENT
                          (Material Balance of Color and TOC)
      Untreated
     Decker Waste
     Color (100)
      TOC (100J
                          Removal by "Massive"
                             Line Treatment
                             (-73)  [-53.0]
                                         Lime-Treated
                                         Waste Contains
                                          (27) [VT.O]
Acid
Treatment
Acid-
Insoluble
< 33,000 »
Acid-
Soluble
t < 1000
                                                     Acid
                                                                  Treatment
                                                      Acid-
                                                      Insoluble
                                                     M  < 2000
                                                                   Acid-
                                                                  Soluble
                                                                 K.. < 500
(85.5)
[51.0]*
(17.5)
(13.8)
[3.3]
                                                             (13.2)
                                                             [1*3.7]
Fractionation
                                                         Fractionation
On
P-60
On
XAD
Bio-Gel + Res






On
P-20
Bio-Gel















Ai(l2.9)[6.2]
Aa (9-W3.9]
Aj (7.l)[2.7l
Ai,(ll.l)[3.8]
A5 (2.6)[0.7l
A, (0.6)[0.15l


A(55.0)[21.9]
B (2.1*) [1.7]
C (2.1) [2.1]
D (2.5) [2.5]
E (0.6) [1.7)
F (O.U) [0.7]
0 (1.7) [1.8]
H (1.6) [1.2]
J (!».!*) (3.1»1
K (0.1*) [1.0]
L (1.2) [1.3]
M(0.25) [0.2]
N(0.25) [0.2]
P(0.25)[0.15l
Q(0.17)[0.15]
R(0.33) [O.UJ
                      IV(10.9)[16.0]
                     III (1.2) [3-0]
                       I (2.5)[l6.2]
                       I (0.9) [7.6]
                                                On
                                                P-60
                                                Bio-Gel
                                                             On
                                                             XAD-8
                                                             Resin
                                                Ai(3.6)[O.Ul]
                                                       IV(9.2)[12.9]
                                                      111(2.8) [7-2]
                                                                   I(0.50)[U.9l
                                                       A (1*.6)[0.52]
                                                       B (1.0)[0.18]
                                                       C (l.l)[0.2l»]
                                                     D+E(0.77)[0.21]
                                                       F (0.8)[0.2l»]
                                                       G (1.0) [0.21*]
                                                       H (l.0)[0.22]
                                                       J (3.1*) [0.58]
                                                       K(0.58)[0.52]
                                                       L(0.1*0) [0.08]
                                                       M(0.1*6)[0.0l*]
                                                       N(0.1»0)[0.06]
                                                       P  —  [0.02]
                                                       Q(0.09)[0.02]
                                                       R(0.l8)[0.0l»]
 apparent  weight average molecular weight.  Color values are shown in parentheses and
 TOC in brackets.  Fraction 'A' from Bio-Gel P-2 was further fractionated on Bio-Gel
 P-6o column.
                                      170

-------
Appendix II.  SUGAR ANALYSIS OF FEEEZE-DRIED WASTES
           (Basis o.d. Volatile Solids)
Massive lime treatment
Sugars, %
Arabinose
Galactose
Glucose
Mannose
Xylose
Total
Indulin
-C
0.37
1.69
0.02
_—
0.52
2.60
Decker
Untreated
0.0k
0.60
2.37
2.U3
10.20
16. Ul
waste
Lime
treated

-------
                                          APPENDIX III
            FRACTIONATION OF  COLOR  BODIES  FROM IPCO'S KRAFT BLEACH CAUSTIC EXTRACT
                               (Material  Balance  of Color and TOC)
         Untreated
      Caustic Extract
        Color (100)
         TOC [100J

        Acid I Treatment
      Acid-
     Insoluble
    MW < 125,000

   (92.8).I
   [T9.3]  !
                                     Removal by "Massive"
                                        Lime Treatment
                                        (-96.0) [-80.1*]
                                          Lime-Treated
                                          Waste Contains
                                           (fc.O) [19.6]
                                                                Acid  Treatment
                         Acid-
                         Soluble
                         <  1100
                      (7.2)  I
                     [20.7]  j
           Fractionation
On
P-60     I
Bio-Gel  I
      Ai(2.2)[2.
      A2(l.8)[2.
      A,(2.8)[3.
                6]
                3]
                3]
      Ag(3.8)[3.3]
      AS(2.5)[1.6]
On
P-2
Bio-Gel
      A(71.6)t55.7]
      B(13.7)[2I*.6]
      C(0. 1*0) [0.87]
      D(0. 16) [0.148]
      E(0.17)[0.3'»]
On
XAD-8
Resin t
    IV (6.9)[13.2]
   111(0.36) [1.0]
    11(0.32) [1.1»]
     1(0.27) [6.6]
Acid- Acid-
Insoluble Soluble
M^ < 10,000 MW <
(1.5) 1 (2.5)
[2.7] J [16.9] .
Fractionation
On 1 On
P-60 XAD-8
Bio-Gel 1 Resin •
Ai(0.08)[0.15] IV
A2(0.12)[0.17] IH(
500
i

•
(1.9) [7.0]
0.15H0.76]
                                                                              I(O.lU)  [7.0]
      0(0. 87) [0.83]
      H(0.21)[0.36]
                                                        A(0.2l»)[0.1H]
                                                        B(0.12)[0.33]
                                                        C(0.06)[0.15]
                                                        D(0.09)[0.ll4]
                                                        E(0.1»3)[0.68]
                                                        F(0.18)[0.30]
                                                        G(O.U)[0.22]
                                                        H(0.0l»)[0.09]
Mw = apparent weight average iralecular weight.   Color values  are  shown in parentheses
     and TOC in brackets.  Fraction "A"  from Bio-Gel  P-2  was  further fractionated on
     Bio-Gel P-60 column.
                                       172

-------
                                      APPENDIX IV
           FRACTIONATION OF COIOR BODIES FROM CONGO'S KRAFT DECKER EFFLUEIJT
                          (Material Balance of Color and TOC)
      Untreated
    Decker Waste
     Color (100)
      TOC [100]
         I
    Acid  Treatment
                                Removed by "Stoichiometric"
                                      Lime Treatment
                                       (-79) [-50]
                                                                 Line-Treated
                                                                 Waste Contains
                                                                   (21) [50]
                                                                Acid I Treatment
    Acid-
  Insoluble
   < 167,000
                     Acid-
                     Soluble
                     i  < 550
                                                           Acid-
                                                          Insoluble
                                                            < 1*1,000
                                                          Acid-
                                                         Soluble
                                                            < 550
(86.5)
[65.8]
                  (17.5)
                  [U9.0]
                                                     (12.8)
                                                     [18.5]
                                                      (8.2)
                                                     [31.5]
     Fractionation
                                                          Fractionation
On
P-60
Bio-Gel 4
      Ai(22.U)[27.J»]
      Aj(13.10 [10.9]
      As (7.U) [U.8]
      A% (2.8) [2.2]
On
P-2
Bio-Gel
On
XAD-8
Resin
     IV .    	
    III (1.6)[2.5]
     11(0.75)17.3]
      I (3.UH9.8]
                                                         I
B
C
D
E
r
0
H
J
(1.
(1.
(2.
(9.
(1.
(2.
(U.
(0.
3)
0)
3)
U)
9)
3)
0)
1»)
[1
(1
tl
(9
[3
•
,
5
k'


• 9]
.3]
•
(3.
[U
[0
7]
8]
• 9]
• 5]
                                                  On !
                                                  P-60
                                                  BiorOel
                                                       Ai(l.9)  [1.2]
                                                       A2(0.8)[0.63]
                                                       A|(l.8)[0.92]
                                                       A*(0.3)[0.22]
                                                       A(5.5)[3.0
On
XAD-8      I
Resin      4
     IV (U.I.
    111(0.27)
   I+II (;
                                                                                  [8.8]
                                                                                  [1.1]
                                                             .0]
                                                             .9]
                                                     C(2.9)[3.5]
                                                     D(l.8)(2.5]
                                                     F(0.8)[1.3]
                                                     0(2.U)[3.7]
• apparent weight average molecular weight.  Color values are shewn in parentheses
  and TOC in brackets.  Fraction "A" from Bio-Gel P-2 was further fractionated on
  Bio-Gel P-60 column.
                                      173

-------
                                         APPENDIX V
                  FRACTIOBATION OF COLOR BODIES  FROM CONGO'S  NSSC EFFLUENT
                             (Material Balance of  Color and TOC)
       Untreated
      NSSC Waste
      Color (100)
       TOC [100}

      Acid  Treatment
             Removed by "Stoichiometric"
                   Lime Treatment
                    (-61*) [-30]
     I	
     Acid-
   Insoluble
  1  < 1*0,000
  (1*8,2)
 [36.0] .,
	1
    Acid-
   Soluble
  M  < 1200

 (51.8) |
 [61*.0] |
                                                                  Lime-Treated
                                                                  Waste  Contains
                                                                    (36)  [70]
                                             Acid  Treatment
On
P-60
Bio-Gel
       Fractionation
      A2(5.5)[6.3j
      A,(0.5)[0.5]
      Ai,(0.5)[0.6]
On
P-2
Bio-Gel
      A(15.6)[16.2]
      B (1.10 [1.7]
      C (0.5) [0.7]
      D (0.9) [1.2]
      E <0.8) [1.1]
      P (0.7) [1-3]
      0 (1.0) [0.7]
      H (2.3) [1.3]
      J (3-M [2.0]
Acid-
Insoluble
L < 25,000
t
Acid-
Soluble
M < 800
  On
  XAI>-8
  Resin •*•
                                                      (20.8)  j              (15-2)
                                                      [35.7]  |              [31*.3)

                                                             Fractionation
                                                    On       .          On
                                                    P-60               XAD-8
                                                    Bio-Gel  I          Resin
111(11.9)[11-0]
 11(15.9)123.6]
  I (5.2)[10.3]
                                                                             IV(6.0)
                                                                            111(2.7)
                                                                 [6.3]
                                                                 [3.8]
                                                         A3(0.2)[0.5l
                                                        II(1».5)111.6]
                                                         1(1.6)  [5.5]
                                                         A(6.3)
                                                         8(1.2)
                                                         C(0.8)
                                                         D(0.6)
                                                         P(-0.6)
                                                         G(7-3)
                                                         H(l.l)
                                                         J(2.3)
                                            [9.3]
                                            [2.1*]
                                            [1.9]
                                            [2.J*]
                                            [1.5]
                                            [2.7]
                                           [11.91
                                            [2.5]
                                            [2.9]
M  * Apparent weight  average molecular veight.  Color values are shown in parentheses
 V   and TOC in brackets.   Fraction "A" from Bio-Gel P-2 was further fractionated on
     Bio-Gel P-60  column.
                                                                    PB.NT.NG OFFICE »74 546-3,9/4,8 ,-3
                                            171*

-------
  SELECTED WATER
  RESOURCES ABSTRACTS
  INPUT TRANSACTION FORM
                     1. Report No.
                            2.
                    3.  Accession No,
  4.  Title

   COI0R CHARACTERIZATION BEFORE AND AFTER T.TMR TREATMENT
  7.  Author(s)
   Dugal, Hardev S.,  Leekley,  Robert M., Swanson, John W.
  9.  Organization

   The Institute  of  Paper Chemistry
                                         5.  Report Daie

                                         6.
                                         8.  1- ttorm.. /;
                                            Report No.
                                        10.  Project No.
                                        11.  Contract/ Grant No.

                                        _s  800853
                                        13  Type i Repci^ , and
                                                                      Period Covered
  12.  Sr 'Tjsori'r Organ' it/on
  15.  Supplementary Notes
                    Environmental Protection Agency report
                    number,'EPA-660/2-74-029, April 197U
  16.  Abstract in general, the lime treatment removed maximum color from the caustic extract
and minimum from the neutral sulfite semichemical (NSSC) effluent.

The massive lime treatment was found to remove 73 percent  color and 53 percent total
organic  carbon (TOC) from kraft decker effluent, and 96 percent color and 80 percent TOG
from  kraft  bleach caustic extract.  The analysis of the solids  from the decker and caustic
effluents showed respective reductions of 73 and 59 percent phenolic hydroxyls, 63 and
26 percent  sugars, and 51 and l6 percent methoxyls by lime treatment.

The stoichiometric lime treatment was found to remove 79 percent color and 50 percent TOC
from  kraft  decker effluent,.and 6U percent color and 30 percent TOC from NSSC effluent.
The analysis of the solids, from the decker and NSSC effluents showed respective reduc-
tions of 76 and 25 percent'phenolic hydroxyls, 31 and "negligible"  percent sugars, and
U2 and 9.7  percent methoxyls by lime treatment.
In the metal ion-lime system the addition of 150-300 ppm FeCl3  with only 300-500 ppm lime
removed  about 98 percent-color from bleach caustic extract.  Over 50 percent of the color
left  by  conventional lime treatment process could also be  removed by incorporating poly-
valent metal ions with. lime.  However, below 1000 ppm of lime,  the  sludge obtained
settled  slowly.  More color could be removed by metal ion-lime  system than when each was
used  individually indicating that a "synergistic" effect, exists.
  I7a. Descriptors *Effluents, *Waste water treatment,  *Colored effluents,  *Color isolation,
 Chemical analysis,  Water pollution, Effluent treatment,  Out plant treatment,
 Secondary treatment, Tertiary treatment, Advanced  treatment.
  nb. Identifiers  *iime treatment, *Massive lime treatment,  ^Stoichiometric lime treatment,
 *Kraft color,  *Neutral sulfite semichemical color,  *Color,  *Decker effluent, *Kraft
 decker effluent, *Caustic extract, *Bleach effluent,  *Kraft bleach effluent, *Kraft
 caustic extract, "Molecular weights, *Color characterization,  "Color isolation.
  lie. COWRR Field & Group
  18.  A vailability
19.
Security Class.
 Repot }
                          '0. Sc:  rityC.'  S.
                             (Page)
                                           21.
No. of
Pages

Pt: .'J
                                                       Send To:
                             WATER RESOURCES SCIENTIFIC INFORMATION CENTER
                             U.S. DEPARTMENT OF THE INTERIOR
                             WASHINGTON. O. C. 20240
  Abstractor H. S. Dugal
            | institution  The Institute of Paper Chemistry
WRSIC 102 (REV. JUNE 1971)

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