EPA-600/2-76-053
March 1976
Environmental Protection Technology Series
HYDROCARBON EMISSIONS REDUCTION FROM
ETHYLENE DICHLORIDE PROCESSES
Industrial Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development. U.S 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
E PA REVIEW NOTICE
This report has been reviewed by the U.S. Environmental
Protection Agency, and approved for publication. Approval
does not signify that the contents necessarily reflect the
views and policy of the Agency, nor does mention of trade
names or commercial products constitute endorsement or
recommendation for use.
This document is available to the public through the National Technical Informa-
tion Service. Springfield, Virginia 22161
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EPA-600/2-76-053
March 1976
HYDROCARBON EMISSIONS REDUCTION FROM
ETHYLENE DICHLORIDE PROCESSES
by
W. S. Amato, B. Bandyopadhyay,
B. E. Kurtz, and R. H. Fitch
Allied Chemical Corporation
Syracuse Technical Center
P.O. Box 6
Solvay, New York 13209
Contract No. 68-02-1835
ROAP No. 21AXM-020
Program Element No. 1AB015
EPA Project Officer: Kenneth Baker
Industrial Environmental Research Laboratory
Office of Energy, Minerals, and Industry
Research Triangle Park, NC 27711
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
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ABSTRACT
This work covers the initial phase of the develop-
ment of a low-emissions ethylene oxyhydrochlorination
process for producing 1,2 dichloroethane (ethylene dichloride)
Firstly, experimental work on an existing pilot
plant scale, once-through process was used to obtain base-
line emission data in mass of hydrocarbon plus ethylene
dichloride per mass of HCl fed as a function of reactor
temperature and percent excess ethylene to the reactor;
and to resolve potential problems which may arise in a
recycle operation, viz., whether CO is oxidized to CO2 by
the reactor, whether post-chlorination might be necessary
in order to save ethylene value in the reactor exit if a
CO oxidation unit were necessary, and whether the reactor
would oxidize methane and ethane, thereby preventing
their buildup in the recycle system.
Secondly, the existing once-through pilot plant
was converted to a recycle operation which then functioned
successfully and yielded emission data in mass of hydro-
carbon plus ethylene dichloride per mass of HCl fed as a
function of reactor temperature and percent excess ethylene
to the reactor. In particular, the project objective of
reducing by 90% the HC + EDC emissions from an ethylene
oxyhydrochlorination process, through the recycling of
reactor off-gases, has been positively demonstrated.
Thirdly, various operating difficulties were
assessed which would be important for future control appli-
cations and scale-up efforts, viz., the increased sensitivity
of the process to upsets in flows, temperatures, and concen-
trations.
Lastly, economic analyses are presented to demon-
strate the competitive position of the improved process.
This report was submitted in fulfillment of
Project Number ROAP 21 AXM 20, Contract Number 68-02-1835,
by Allied Chemical Corporation, Industrial Chemicals
Division, Syracuse Technical Center, under the sponsor-
ship of the Environmental Protection Agency. Work was
completed as of June 1975.
111
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CONTENTS
Page
Abstract ill
List of Figures v
List of Tables vii
Acknowledgments viii
SECTIONS
I Conclusions 1
II Recommendations 4
III Introduction 5
IV Preliminary Evaluation of Alternative
Approaches 13
V Description of Experimental Program
and Equipment 20
VI Experimental Work 32
VII Results 50
VIII Computer Simulation and Economic Study 59
IX References 67
X List of Inventions 68
XI Glossary 69
XII Appendix 70
iv
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LIST OF FIGURES
Paqe
Figure 1 Flowsheet for Existing Ethylene
Oxyhydrochlorination Process 7
Figure 2 Flowsheet for Proposed Ethylene
Oxyhydrochlorination Process 9
Figure 3 Conceptual Flow Diagram of Ethylene
Oxyhydrochlorination with Vent Gas
Recycle and Oxygen Feed 14
Figure 4 Conceptual Flow Diagram of Catalytic
Oxidation Process for Disposal of
Oxyhydrochlorination vent 16
Figure 5 Conceptual Flow Diagram of Thermal
Incineration Process for Vent
Gas Disposal 18
Figure 6 Simplified Flowsheet of Pilot Plant
Oxyhydrochlorination Recycle Process . 22
Figure 7 Flowsheet 1 OHC Pilot Plant 28
Figure 8 Flowsheet 2 OHC Pilot Plant 30
Figure 9 Wet EDC Purity Wt. % vs. Reactor
Temperature °C for Once-Through
Process 51
Figure 10 Total HC + EDC Emissions kg(HC + EDC)/
kg HCl vs. % Excess Ethylene with
Reactor Temperature as Parameter
for Once-Through Process 52
Figure 11 Wet EDC Purity Wt. % vs. Reactor
Temperature °C for Recycle Process ... 54
Figure 12 Total HC + EDC Emissions kg(HC + EDC)/
kg HCl vs. % Excess Ethylene with
Reactor Temperature as Parameter
for the Recycle Process 55
Figure 13 1-Percent Reduction in Emissions
Recycle Compared to Once-Through vs.
% Excess Ethylene with Reactor
Temperature as parameter 57
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LIST OF FIGURES
(Continued)
Pac
Figure 14 % HC Emissions Reduction vs. %
CH4 in C2H4 Feed 61
Figure 15 % HC Emissions Reduction vs. %
C2H6 in C2H4 Feed 62
Figure 16 Effect of Oxygen and Ethylene Costs
on Incremental Manufacturing Costs
for Recycle Oxyhydrochlorination
Process vs. Conventional Process 66
VI
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LIST OF TABLES
Page
Table 1 Comparison of Economics for various
Vent Gas Treatment Processes 13
Table 2 Preliminary Cost Study Oxy Process
with 02 Feed and Vent Gas Recycle
Comparison with Old Process
Air Feed and No Recycle 15
Table 3 Preliminary Cost Study Catalytic
Oxidation Process for vent
Gas Disposal 17
Table 4 Preliminary Cost Study Thermal
Incineration for Disposal for
Oxy Vent Gas 19
Table 5 Legend for Flowsheets, Figures 7 and 8 . 25
Table 6 Summary of CO Addition Runs 37
Table 7 Results of CH4/C2H6 Additions 39
Table 8 Outline of Experimental Runs Obtained
on Recycle Operation with
Oxygen Feed 48
Table 9 H-Percent Reductions of Emissions at
Various Excess Ethylene values and
Reactor Temperatures 56
Table 10 Example of Computer Simulation 60
Table 11 Incremental Capital Cost Comparison .... 64
Table 12 incremental Manufacturing Cost
Comparison 65
VII
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ACKNOWLEDGMENTS
The efforts of Mr. L. S. Tracy in the economic
analyses is hereby gratefully acknowledged.
Vlll
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SECTION I
CONCLUSIONS
The conclusions appropriate for this report will
be listed in the following order: (1) preliminary economic
evaluation of alternative approaches; (2) experimental
results for once-through operation; (3) experimental
results for recycle operation; (4) emissions reduction
recycle compared to once-through; (5) simulation work
(program) for scale-up; and (6) commercial plant economical
study.
The preliminary economic evaluation of alternative
approaches compared the proposed recycle system with
catalytic oxidation and incineration. It was found that
the recycle system would be considerably more economic
than the other two possibilities.
The experimental results of once-through operation
were:
(a) Crude ethylene dichloride (EDC) purity* varied
inversely linearly with reactor temperature.
(b) Kilograms of hydrocarbon plus ethylene dichloride
per kilograms of HCl emissions could be correlated
as a linear function of excess ethylene to the
reactor with reactor temperature as parameter.
(c) Ethylene efficiency decreases with higher operating
temperature due to increased oxidation of ethylene.
(d) Addition of carbon monoxide to the feed gases
indicated that CO was oxidized to CO2; also large
additions of COg to the feed gases did not
adversely affect the reaction.
(e) Methane passed through the reactor system unchanged
and ethane was significantly reduced (80% in this
case) over inlet values.
(f) Post-chlorination of excess ethylene in the reactor
exit gases was feasible provided chlorine was
injected into the gas phase and not the catalyst
itself.
* See Glossary for definition of abbreviations.
-------
The experimental results of recycle operation
were:
(a) Crude ethylene dichloride (EDC) purity
varied inversely linearly with reactor
temperature, but was a few tenths of a
percentage point lower than the once-
through purity at the same temperature.
(b) The ethylene efficiency for the recycle
operation was higher than that for the
once-through process due to the recycling
of off-gases.
(c) Ethylene efficiency decreases with
higher operating temperature due to
increased oxidation of ethylene.
(d) All runs of this report involved the
recycling of greater than 90% of the
reactor off-gases.
(e) Kilograms of hydrocarbon plus ethylene dichloride
per kilograms of HCl emissions could be correlated
as a linear function of excess ethylene to the
reactor with reactor temperature as parameter.
(f) The recycle operation is more sensitive
than the once-through operation and
requires closer control for successful
operation.
Comparison of the emissions data for once-through
and recycle operation indicates that the percent reduction
of HC + EDC emissions have exceeded 90% for all runs
conducted in this work.
It was possible to develop a computer simulation
program, based on actual experimental data, which could
duplicate vent gas compositions and superficial velocities
at given reactor temperatures and pressures for given excess
C2H4/oxygen values to the reactor. The utility of this program
was in its use for scale-up calculations which were used
in the Incremental Economic Analysis for a commercial unit
of 700 MM Ibs EDC/year capacity. Based upon the optimum
experimental conditions from recycle operation, viz.,
230°C, 5-7% excess ethylene and 50% excess oxygen, together
with this simulation program, it was found that the recycle
process was competitive with existing processes to within
a tenth of a percent of total incremental capital and
manufacturing costs.
-------
Finally, it is concluded that closer control
of the recycle process via computer technology will over-
come the inherent sensitivity of the process and lead to
more consistent data and operation.
-------
SECTION II
RECOMMENDATIONS
The work of this report has revealed that the
newly-developed recycle process is much more sensitive
to upsets than the conventional once-through process.
This sensitivity results in an apparent narrow range of
operability and difficulty in maintaining stable condi-
tions. Before a commercial prototype of the proposed
process can be designed, these sensitivity factors must
be more fully explored along with the establishment of
well-defined requirements necessary for stable operation.
Thus, it is recommended that further work be performed on
the newly-developed recycle process through the use of
computer control technology to clearly delineate operating
parameters affecting stability and to define the operating
range of such parameters yielding satisfactory process
performance.
Secondly, it is recommended that the effect of
operating parameters on the existence and build-up of
organic by-products (which must be vented) be investigated.
Specifically, this recommendation is directed to the
possible build-up of vinyl chloride in the recycle system
with its consequent venting to the atmosphere.
Lastly, it is recommended that long-term,
closely-controlled runs be made to determine the above
mentioned build-ups of organics and also, to determine
the effect of recycle operation on catalyst performance
and life.
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SECTION III
INTRODUCTION
GENERAL
The production of vinyl chloride in the United
States is almost exclusively based on ethylene and
involves three main steps:
Direct Chlorination of Ethylene
^2*14 "I"
Oxyhydrochlorination of Ethylene
C2H4 + 2 HC1 + 1/2 02 ^- C2H4C12 + H20
Cracking of Ethylene Dichloride
2 C2H4C12 ^- 2 C2H3C1 + 2 HCl
The overall reaction in this balanced process is
2 C2H4 + C12 + 1/2 02 ^- 2 C2H3C1 + H20.
The Oxyhydrochlorination step is the most technically
difficult part of the overall process and has had a
profound impact on the industry since its development.
The first commercial ethylene Oxyhydrochlorination
process appeared in 1964 and within the next few years
nearly 90% of the classical process for vinyl chloride
from acetylene was displaced.
EXISTING PROCESS
There are currently two basic variants of
ethylene Oxyhydrochlorination processes, those employing
fixed catalytic beds and those employing fluid
catalytic beds. Most of the major producers employ
a fluid bed. Ethylene, hydrogen chloride and air are
introduced into the bottom of the fluid bed where the
Oxyhydrochlorination reaction takes place. The heat
released by the reaction is substantial, so the reactors
are equipped with internal cooling coils which are
submerged in the fluid bed.
-------
Downstream product recovery involves cooling of
the reactor exit gases by either direct quench or a heat
exchanger, followed by condensation of the ethylene
dichloride product and water by-product which are separated
by decantation. The remaining gases still contain 1 to 5%
by volume of ethylene dichloride, so they are further
processed in a secondary recovery system employing either
solvent absorption or a refrigerated condenser. The off-gas
is then vented to the atmosphere. See Figure 1.
The vent stream contains 85 to 95% nitrogen from
the air employed as a source of oxygen for the oxyhydro-
chlorination reaction. It also includes a variety of
other compounds which originate either in the feeds to the
reactor or as by-products of the oxyhydrochlorination:
Carbon dioxide and carbon monoxide formed
by oxidation of ethylene
Ethyl chloride formed from a side-reaction
of ethylene with hydrogen chloride
Methane and ethane which are impurities in
the ethylene feed and pass through the
reactor unaffected
Ethylene dichloride which escapes from
the secondary recovery system
Solvent which escapes from the secondary
recovery system
Ethylene which is unreacted.
The aspect of most current ethylene oxyhydro-
chlorination processes which contributes the most to
hydrocarbon emissions is the use of air as the source of
oxygen. The inerts (nitrogen) accompanying the air
necessitate a once-through process. If pure oxygen were
used it would be possible, at least in theory, to recycle
the reactor off-gases. Only one plant currently employs
pure oxygen, but it does not recycle the reactor
off-gases.
PROPOSED PROCESS
Recycle of reactor off-gases will eliminate
the need for a secondary recovery system and the resultant
losses of solvent which typically amount to 0.001 ton per
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EDC,WATER
OXY
REACTOR
FEEDS:
CRUDE
EDC
COND.
CW
HOT
QUENCH
COLUMN
Ln_J\
VENT GAS
REFRIG. COND.
DECANTER
SEPARATOR
CRUDE,WET
EDC
J
WASTE
WATER
EDC
RICH
ABSORBER
AIR COMPRESSOR
FIGURE 1:
FLOWSHEET FOR EXISTING ETHYLENE OXYHYDROCHLORINATION PROCESS
STRIPPER
-------
ton of EDC. It will also eliminate unreacted ethylene.
Some means will have to be employed to limit build-up of
feed impurities (methane and ethane) and by-products
(carbon dioxide, carbon monoxide and ethyl chloride),
probably a combination of removal by chemical or physical
processing and a purge to atmosphere. The purge, however,
will amount to only a small fraction of the vent stream
which characterizes present processes and it is certainly
reasonable to expect a 90% reduction in hydrocarbon
emissions over present processes.
The detailed technical approach currently
visualized may best be explained by reference to
Figure 2 Flowsheet for Proposed Low-Emissions Process
for Producing Ethylene Bichloride by Ethylene Oxyhydro-
chlorination.
A fluid bed oxyhydrochlorination reactor
employing a conventional copper chloride on alumina
catalyst is fed with ethylene, hydrogen chloride and
recycle gas containing added oxygen. The ethylene is in
5% excess over that required by the reaction stoichiometry,
the oxygen in 60 to 80% excess. Near the top of the fluid
bed a small stream of chlorine, amounting to 2 to 5% of
the hydrogen chloride feed, is added to convert the
unreacted ethylene to additional ethylene dichloride.
The gases leaving this reactor contain the
products of reaction, ethylene dichloride and water, and
other substances originating as unreactive impurities in
the feeds or as by-products. The gases pass to a quench
column where they are cooled by circulating water then to
a condenser where ethylene dichloride and water are
recovered. These are separated in a decanter and the
non-condensable gases flow through a recuperative heat
exchanger where they are re-heated.
The hot gases pass to a fixed bed oxidation
reactor (shown dashed) employing a platinum on alumina
catalyst where the carbon monoxide will be converted to
carbon dioxide by reaction with the excess oxygen from the
oxyhydrochlorination reactor. The gases exiting the
reactor are cooled against the entering gases in the
recuperative heat exchanger and passed to a booster
compressor. It may be possible to eliminate the separate
carbon monoxide oxidation step if it can be shown that CO
can be oxidized to CC>2 by recycle to the oxyhydrochlor-
inator. If this is possible, then the need for post-
chlorination is obviated.
8
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RECYCLE
CO OX UNIT __/T
EDC,WATER
FEEDS:
STRIPPER
HOT QUENCH
COLUMN
WASTE
WATER
FIGURE ?:
FLOWSHEET FOR PROPOSED ETHYLENE OXYHYDROCHLORINATION PROCESS
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The majority of the discharge from the booster
compressor is recycled to the oxyhydrochlorinator. This
recycle gas will be predominantly carbon dioxide with the
process as described here. A small portion of the recycle
gas is purged in order to limit the build-up of unreactive
impurities which enter the system with the reactor feeds,
for example; methane and ethane which are typical
impurities in the ethylene.
This purge stream is first cooled in a recupera-
tive heat exchanger and then further cooled in a refrigera-
ted vent condenser which removes most of the ethylene
dichloride and ethyl chloride. These are collected in a
receiver from which the purge gases, consisting of 80-90%
carbon dioxide and 10% methane and ethane, are discharged
through the recuperative heat exchanger and may be disposed
of via incineration.
The net effect of this process will be at least
a 90% reduction in hydrocarbon emissions compared to
typical present processes. Thus, the objective and scope
of this project can be stated as:
OBJECTIVE AND SCOPE OF PROJECT
The objective of the project was to demonstrate
that emissions from the production of ethylene dichloride
by oxyhydrochlorination of ethylene could be reduced in a
modified process by at least 90% from the levels
encountered with typical existing processes. The modified
process was to employ recycle of reactor exit gas, oxygen
feed and whatever additional processing steps are determined
to be necessary to control build-up of by-products in the
recycle stream and was to be economically competitive with
present-day processes. The process performance was to be
evaluated on a laboratory scale and a preliminary study of
technical and economic feasibility was to be carried out.
BENEFITS OF SUCCESSFUL EFFORT
The ethylene oxyhydrochlorination vent is the
main source of hydrocarbon emissions associated with the
manufacture of vinyl chloride. The direct chlorination
process produces less than one-tenth of the hydrocarbon
emissions of oxyhydrochlorination and cracking of ethylene
dichloride, under normal circumstances, produces no
emissions. Ethylene dichloride production is stated to
account for 28% of the hydrocarbon emissions in the Southern
Louisiana and East Texas AQCRs. (5)
10
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There is no practical way of eliminating the oxy-
hydrochlorination vent from existing processes; the gases
are too dilute for direct incineration and the addition of
natural gas to make the gases combustible is an extravagance.
Furthermore, incineration will form hydrochloric acid which
must be recovered by scrubbing.
The primary anticipated benefit from this project
is at least a 90% reduction in hydrocarbon emissions for
the proposed process as opposed to presently existing
processes, which currently average approximately 0.03 Ib
hydrocarbons per pound of ethylene dichloride product. It
is believed that this can be accomplished with only a modest
increase in capital cost and it is anticipated that the
benefits of increased raw material yields will off-set
this to a great extent.
OUTLINE OF PROJECT
Four major tasks for this project were indicated.
The first represented the completion of the cursory study
of alternative approaches to reduction of emissions and was
required to define in detail the experimental program to
follow. The second task represented the point at which
the modifications and additions to the existing laboratory
oxyhydrochlorination equipment had advanced sufficiently to
allow the experimental program for determining the effects
of operating conditions to begin. The third task was the
point at which the experimental program had advanced
sufficiently far to initiate the preliminary technical and
economic evaluation of the process. The fourth task was
the point at which a recommendation for a future course of
action could be made, including, if warranted, preparation
of a proposal for a follow-on contract for further
development of the process.
The plan of operation consisted of the following
tasks, which were directed toward a demonstration of the
technical and economic feasibility of the processes:
Task 1 Preliminary evaluation of
alternative approaches to
reduction of emissions from
ethylene oxyhydrochlorination.
Task 2 Modifications and additions to
equipment.
11
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Task 3 Determination of the effects
of operating conditions on the
performance of the existing and
proposed processes.
Task 4 Preliminary technical and economic
evaluation of the proposed process.
The first step in the plan of operation was the
preliminary evaluation of the various conceivable approaches
to the reduction of emissions from ethylene oxyhydro-
chlorination. Comparisons with the proposed process were
made.
12
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SECTION IV
PRELIMINARY EVALUATION OF ALTERNATIVE APPROACHES
The preliminary evaluation of alternative
approaches considered the following process alternatives:
oxygen feed with vent gas recycle on the existing process;
catalytic oxidation of vent gas; and thermal incineration
of the vent gas.
The results of the economic evaluations of
these alternatives show clearly that the oxygen addition
with vent gas recycle on the existing process is by far
the most economic choice. The estimates are based on a
700 MM Ib/year EDC plant.
The results can be summarized as shown in
Table 1.
Tables 2, 3 and 4 and Figures 3, 4 and 5
illustrate the processes considered and their detailed
capital and manufacturing cost considerations.
Two other schemes, compression of vent gas with
absorption in a solvent, the adsorption of the hydrocarbons
which occur in the vent gas, do not at first look, appear
to be worth considering in detail, since initial economic
considerations militate against them.
TABLE 1
Economic Consideration
Net Capital increase
Net increase in
Manufacturing Cost
Unit Cost increase,
4/lb EDC
process
Oxy Feed
Recycle
($1,300,000)*
$377,000/y
0.054
Thermal
Incineration
$1,750,000
$695,000/y
0.099
Catalytic
Oxidation
$2,250,000
$985,000/y
0.141
* Figures in parentheses refer to savings in capital.
13
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PLUME. BURNER
OXYGEN
HC1
RECYCLE
RECYCLE
COMPRESSOR
H
a
o
00
LEAN SOLVENT
* FROM STRIPPER
EDC RICH
'SOLVENT TO
STRIPPER
ETHYLENE
WASTE WATER
FIGURE 3: CONCEPTUAL FLOW DIAGRAM OF ETHYLENE OXYHYDROCHLORINATION WITH
VENT GAS RECYCLE AND OXYGEN FEED
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TABLE 2
PRELIMINARY COST STUDY
OHC PROCESS WITH O2 FEED AND VENT GAS RECYCLE
COMPARISON WITH OLD PROCESS
AIR FEED AND NO RECYCLE
Fixed Capital; New Process Old Process
Air Compressor 3 - $ 540,000
Recycle Compressor 210,00
EDC Recovery System on
Off Gas 45,000 180,000
Off Gas Plume 50,000
Purchase CostMajor
Equipment: $ 305,000 $ 720,000
Net Saving 415,000
Factored Costs 415,000
Total Direct Saving 830,000
Saving in Overhead and
Fees 470,000
Net Capital increase (1,300,000)
Manufacturing Costs;
02 65,000 NT at $25 $ 1,625,000
C2H4 Credit 1580 NT at $100 (158,000)
EDC Credit 2280 NT at $64 (146,000)
Electric Power (Credit)
27,500 MKWH at $14 (385,000)
Maintenance Credit 7% of F.C. (91,000)
Depreciation Credit
10% of F.C. (130,000)
Taxes and Insurance Credit
1% of F.C. (13,000)
Net Manufacturing Cost $ 702,000
Return on Investment
Credit 25% (325,000)
Net Cost including ROI Credit - $ 377,000
Unit Cost increase
4/lb EDC 0.054
15
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VENT
NaOH
LIQUOR
CAUSTIC
SCRUBBER
QUENCH
WATER
WASTE WATER
_P_RQCESS VENT GAS
AIR
CATALYTIC
OXIDATION
REACTOR
COMPRESSOR
NATURAL GAS
STEAM
DRUM
BOILER
PEED WATER
BDOW
DOWN
FIGURE k: CONCEPTUAL FLOW DIAGRAM OF CATALYTIC OXIDATION PROCESS FOR
DISPOSAL OF OXYHYDROCHLORINATION VENT
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TABLE 3
PRELIMINARY COST STUDY
CATALYTIC OXIDATION PROCESS FOR
VENT GAS DISPOSAL
Capital Cost;
F.O.B. Equipment Cost $ 610,000
Factored Costs 765,000
Catalyst 60,000
Sub-Total $ 1,435,000
Contractor's Fee $ 70,000
Engineering, Contingency and
Overheads 745,000
Grand Total $ 2,250,000
$/Year
Manufacturing Costs;
Labor $ 22,000
Maintenance, 7% of F.C. 180,000
Supplies 18,000
Catalyst Make-up 60,000
Electricity 120,000
Water 15,000
Caustic Soda 265,000
Steam (Credit) 144,000 NT
at $3.50 (504,000)
Depreciation 225,000
Taxes and Insurance 22 , OOP
Total Manufacturing Cost $ 423,000
25% Return on Investment 562,000
Total Cost Including ROI $ 985,000
Unit Cost Increase
4/lb EDC 0.141
17
-------
PROCESS VENT.
oo
FUEL GAS
AIR
THERMAL
INCINERATOR
STEAM
L
FLUE GAS
QUENCH
WATER
WASTE
HEAT
BOILER
BO
NaOH
LIQUOR
AUSTIC
SCRUBBER
CLER
FEED WATER
FIGURE 5: CONCEPTUAL FLOW DIAGRAM OF THERMAL INCINERATION
PROCESS FOR VENT GAS DISPOSAL
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TABLE 4
PRELIMINARY COST STUDY
THERMAL INCINERATION FOR DISPOSAL
FOR OXY VENT GAS
Capital Costs:
(F.O.B. Equipment Costs per Houdry with Escalation)
Thermal Incinerator $ 105,000
Waste Heat Boiler and
Auxiliaries 175,000
Caustic Scrubbing Equipment 215,OOP
Purchase Cost Major
Equipment $ 495,000
Factored Costs at 125% 620,000
Total Direct Cost $ 1,115,000
Overheads and Fees 635,000
Total Fixed Capital $ 1,750,000
Manufacturing Costs:
Labor $ 22,000
Maintenance 7% of F.C. 122,500
Supplies 10,000
Fuel 57,000 MM BTU at $1.15 66,000
Boiler Feed Water 15,000
Caustic Soda 3305 NT at $80 - 265,000
Steam Credit 124,500 NT
at $3.50 (436,000)
Depreciation10% of F.C. 175,000
Taxes and Insurance
1% of F.C. 18,000
Total Manufacturing Cost $ 257,500
25% Return on Investment 437,000
Total" Cost Including ROI $ 694,500
Unit Cost Increase
4/lb EDC 0.099
19
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SECTION V
DESCRIPTION OF EXPERIMENTAL PROGRAM
AND EQUIPMENT
EXPERIMENTAL PROGRAM
The development of a successful recycle process
which would reduce emissions by at least 90% depended on
the answer to several important questions which were best
evaluated in a once-through process.
Since the recycle process concept depended for
its success on the build-up of inerts (C02) in the system
to replace nitrogen which was absent due to the use of
oxygen instead of air, certain questions needed to be
resolved before development of a recycle process and which
depended on the chemistry of the process.
The main chemical reactions which occur in
fluid-bed oxyhydrochlorination of ethylene are:
Principal Reaction:
C2H4 + 2 HC1 + 1/2 O2 - ^- C2H4C12 + 2 H2O (1)
Cupric Chloride
Catalyst
(2)
(3)
(4)
(5)
Main Side Reactions:
C,H4 + 2 07
C2H4 + HCl -^
2 CO + 02 ^
Questions Needing Resolution
* 2 CO + 2 H5O
^" 2 CO +2 HoO
~^^^^ CpMeCJ.
*" 2 ^2
Before Final Development
of a Recycle Process
Question 1: Will CO build-up in the recycle system
reach levels which will cause explosive
conditions?
20
-------
Question 2:
Question 3:
Question 4:
Will the ratio of C02/C0 remain at
about 2 in the recycle system as it
does in the once-through system?
Can the reactor system effectively
oxidize CO to C02?
If CO is not oxidized in the reactor,
but is oxidized in a separate unit,
how do we avoid the loss of ethylene
value by oxidation?
Can post-chlorination effectively work
on the exiting reactor gases to convert
unreacted ethylene to EDC?
What is the effect of the reactor
system on hydrocarbon impurities,
such as CH4 and C2H6, which might
occur in the ethylene feed?
With these questions before us, the scope of an
experimental program was evolved as follows:
Scope of the Experimental Program
1. Once-Through Runs
(a) Baseline runs at 230-240°C with 5, 10, 15%
excess C2H4 and 60-70% excess O2 (as air).
(b) Runs with CO and C02 additions.
(c) Hydrocarbon additions CH4 and C2H6.
(d) Post-chlorination work.
2. Recycle Runs (02 Feed)
(a) Runs at 230, 240, 250°C with 5-20% excess
C2H4 and 50-115% excess O2 with vent rates
of less than 10% of the total off-gases.
DESCRIPTION OF LABORATORY OHC PILOT-PLANT EQUIPMENT
ONCE-THROUGH SYSTEM
Reference to Figures 1 and 6 will aid in the
description of the once-through OHC pilot plant. Although
Figure 1 shows an absorber-stripper arrangement which is
used in commercial operation, the laboratory version used
a refrigerated condenser instead. Also, even though
Figure 6 describes the simplified recycle process, the
21
-------
OXY
REACTOR
ROTAMETERS
AND
PREHEATERS
to
to
AIR Og C2H4 HC1
FIGURE 6:
WATER IN , REACTOR PRESSURE
CONTROL
CYCLON
ORTHO
.COOL-
ING
COND
STI
COND.2
*
HOT
QUENCH
TOWER
WATER
OUT
^
/-
D
V
ECANTER
J
VENT PRESSURE
CONTROL
RECYCLE
COMPRESSOR
] ANALYZERS
T
T
5ATALYST
RETURN LEG
AQUEOUS
PRODUCT
T
MeCl
ACETONE
CRUDE EDC
PRODUCT REFRIGERATED
CONDENSER
SAMPLE
BOMB
-M-
-K-
RECYCLE LINE
!JMJIED FLOWSHEET OF PILOT PLANT OXYHYDROCHLORINATION
PROCESS
WATER
IN VENT
WATER
OUT
SCRUBBER
-------
once-through process can be seen in this diagram by
following the dashed flow line after the reactor pressure
control valve, thereby by-passing the entire recycle
system.
The once-through process begins with the
cylinder gas supplies and flow metering equipment.
Ethylene used in the process is 99.6% pure or better.
HCl is a technical grade which contains some moisture
(removed with a CaCl2 drier in the system), and oxygen
was a commercial grade with a 99.6% pure or better
specification. Flows were monitored at constant tempera-
ture and pressure through banks of calibrated Fischer and
Porter Tri-Flat rotameters and into individual electrically-
heated, stainless steel preheaters (nickel for HCl).
Air or oxygen was fed separately into the bottom
of the reactor spool piece and the ethylene and HCl flows
were mixed together in a mixing tee at their entrance into
the reactor. The reactor consisted of a 2 1/2 inch
diameter pipe 15 feet high with a four foot disengaging
section of 8 inch diameter pipe at the top. catalyst was
a typical cupric chloride on alumina variety. The reactor
had pressure taps and thermocouple locations as illustrated
in the detailed flowsheets, Figures 7 and 8. Control of
reactor temperature and removal of the heat of reaction was
accomplished by a cooling jacket on the lower five feet of
the reactor and cooling coils on the next four feet of
reactor which utilize Dowtherm E as coolant. The Dowtherm
was cooled by means of a water heat exchanger.
Reactor gases passed into a TML Dorrclone to
remove catalyst fines (returned via the catalyst return
leg) which were necessary for proper fluidization. The
hot gases then passed into the bottom of the hot quench
tower where they were cooled and scrubbed of unreacted
HCl.
The cooled gases then passed to condensers
where both EDC (ethylene dichloride) and water are
condensed out and flow to the decanter for separation and
collection. The non-condensables (02, N2, CO, CO2f C2H4,
trace EDC) then flowed through the reactor pressure control
valve which regulates the pressure back to the reactor.
The once-through process then passed these
off-gases through a methylene chloride-acetone-dry ice
cooled refrigerated condenser which operated at <-40°C and
which removed residual EDC. Commercially, this is usually
accomplished with an absorber-stripper arrangement.
23
-------
Gas sample bombs could be taken downstream of
this refrigerated condenser. Final gases passed to a
packed scrubber, the gaseous effluent of which passed
to a roof vent.
RECYCLE SYSTEM
Figures 2,6, 7 and 8 illustrate the recycle
system components. The components of the once-through
process were utilized directly in the recycle process.
The flow description for the recycle process will
be picked up from the reactor pressure control valve since
both systems were similar up to this point.
The gases passing through the reactor pressure
control valve fed the inlet to the ITT Pneumative, triple
piston, single-stage recycle compressor Model SGH71-T.
Due to leakage past the pistons*, the compressor was housed
in a pressurized enclosure fabricated from 16" steel pipe
which was closed at one end with a welded plate and at the
other with a blind flange. Pressures between 40-60 psig
were maintained by means of a cylinder of C02- Flow rates
of this C02 stream were noted and recorded.
The exit gases from the recycle compressor
(60-90 psig) were fed to a bank of three rotameters in
parallel. The first rotameter was the vent rotameter
which fed the vent pressure control valve. The setting of
the controller for this valve determined the vent rate and
thus the recycle rate also. The next rotameter was the
recycle rotameter which fed back to the reactor bottom
(after preheating). The third rotameter was the
sample rotameter which controlled flow to the
Beckman Model 742 Polarographic oxygen analyzer and the
Beckman Model 865 infrared ethylene analyzer. Provision
was made (as shown in the detailed flowsheets, Figures 7
and 8) to calibrate each gas analyzer separately with its
own gas supply and metering system.
The vent was passed through the methylene
chloride-acetone refrigerated condenser to the sample
bomb and out to the scrubber.
The complete flowsheets, Figures 7 and 8, give
the entirety of the recycle process. The accompanying
legend, Table 5, identifies additional components and
data monitoring points.
* Only a pilot plant problem; not anticipated to be a
problem in industrial operation.
24
-------
TABLE 5
LEGEND FOR FLOWSHEETS
FIGURES 7 AND 8
Low air pressure alarm
A2 Low HCl pressure alarm
A3 HC in air explosive alarm
A4 HC in air explosive alarm
Ci CAL-Rod
COi Recycle gas cooler (for moisture elimination)
DI HCl dryer
D2 Sample rotameter filter and dryer
03 C2H4 inlet sample filter and dryer
04 C2H4 inlet calibration filter and dryer
FI Air filter
F2 Purge recycle filter
F3 Recycle inlet filter
F4 Recycle outlet filter and moisture eliminator
HS Heat Strip-Reactor Top flange
HTi HCl line heat tape
m?2 C2H4 line heat tape
HT3 Reactor top vent tape
HT4 Reactor exit line to quench heat tape
HT5 Purge recycle heat tape
HTg Quench water heat tape
HTy Recycle line heat tape
M Mercury manometer pressure relief leg
P-j^ Ortho-dichlorobenzene-recirculating pump (DowthermE)
?2 MeCl/acetone circulating pump
Air regulator
RE2 CH4 regulator
REs CH4 regulator to calibration set-up
RE4 C2H4 regulator to rotameter
RE5 Recycle regulator
REg Sample regulator
REy Secondary C2H4 regulator to C2H4 rotameter
in calibration system
RO-, Oxygen rotameter
R02 Air rotameter
R03 C12 rotameter
R04 HCl rotameter
25
-------
R05 CH4 rotaraeter
ROg C2H4 rotameter
ROy Ortho cooler (water) rotameter
ROg Quench water rotameter
ROg Vent rotameter
ROio Recycle rotameter
ROn Sample rotameter to meters
R0i2 C2H4 rotameter for sample (C2H4 meter)
system calibration
R0^3 C02 or N2 rotameter for sample system
calibration
C2H4 in CO2 rotameter for sample (C2H4 meter)
system calibration
Vent rotameter (after refrigerated condenser
and to scrubber)
26
-------
TEMPERATURE LEGEND
TIRj Reactor top
TIR2 Reactor top
TIR3 Reactor bed
TIR4 Reactor bed
TIRs Reactor bed
TIRg Reactor bottom
TIRy Air/recycle entering reactor
TIRs Reactor bed (reactor temperature-control point)
TIRg Reactor bed
TIRio Dowtherm jacket
TIR11 Mixing tee C2H4 and HCl
TIR12 Quench tower bottom
TI-^3 Reactor exit gases
TI-^4 Product condenser
TI^5 Ethylene preheater
Tl^g HCl preheater
TI]_7 Air/recycle preheater
Tlig Reactor top flange
Tlig Non-functional
TI20 Reactor head space
Tl£i Reactor bed
TI22 MeCl/acetone to refrigerated condenser
TI23 Acid leg (quench)
TI24 Ortho cooler condensate return
TI25 Quench tower top
TI26 Ortho cooler in
TI27 Ortho cooler out
TIW28 Vent gas to analyzer
TI29 Recycle and vent
TI30 C2H4 used in calibration
1131 Oxygen to reactor
TI32 Oxygen preheater
TI33 Compressor enclosure
27
-------
FIGURE 7
ALLIED CHEMICAL CORP.
SYRACUSE TECHNICAL CENTER
SOLVAY, N.Y. 13209
OHC PILOT PLANT
02 SUPPLY
28
-------
FIGURE 7
20«
VENT
VENT
AQ. PRODUCT CR. OX PRODUCT
29
-------
FIGURE 8
REACTOR PRESSURE
CONTROL VALVE
VENT PRESSURE r*
CONTROL VALVE
V
I *f
/
GAS SAMPLE BOMB
1
r" i
REFRIGERATED
CONDENSER
30
-------
FIGURE 8
DRY ICE
Chip2-ACETONE COOLER
ALLIED CHEMICAL CORP.
SYRACUSE TECHNICAL CENTER
SOLVAY, N.Y. BZ09
OHC PILOT PLANT
31
-------
SECTION VI
EXPERIMENTAL WORK
ONCE-THROUGH PROCESS
The initial work of the once-through process was
designed at evaluating baseline emission data. Further
work centered around determining the effects of CO, C02,
CH4 and C2H6 on the reactor system and lastly, the possibil-
ity of post-chlorination of reactor gases.
The experimental variables measured for the
once-through process are listed, together with all data,
in APPENDIX TABLE 1. Of the streams that required chemical
analysis were, the vent gas bomb, crude product, aqueous
product, and quench bottoms. The results of chemical
analysis, together with all flows, were processed in a
computer material balance program* to give conversions,
yields, efficiencies of all reactants, composition of the
vent and waters, and crude product composition. Sampling
was done on the basis of one hour periods (with a few
noted exceptions). Following will be a discussion of each
experimental run, its purpose and its general results.
Experimental Runs
The analytical data for the products of reaction
and vent gas analysis are obtained as follows: organic
products obtained through gas chromatography; aqueous product
and quench bottoms direct titration for HCl and gas chroma-
tographic analysis for EDC; vent gasesgas chromatography.
Runs 1-5
Runs 1-5 had the function of obtaining baseline
data, evaluating catalyst performance, and training operating
personnel, together with selection of reactor temperature and
pressure.
The runs were organized as follows: Runs 1-5 deal
with different excess ethylene ratios, with each run allowing
for two operating temperature periods. For example, Run 3
had 10.1% excess ethylene, with 4-1 hour periods of data
sampling. The first two periods were at 240°C and the last
two were at 230°C. Another variable, excess air, has been
* Available on request from Industrial Environmental Research
Laboratory of EPA.
32
-------
maintained at 60-73% for all runs. The initial baseline
data was obtained for 20.0, 16.1, 10.1 and 5.1% excess
ethylene.
The vent gas analyses for Runs 1-5 are useful
for comparing the Runs 6-8. For all baseline runs, the N2
is present between 87-91%. CO varies between 0.6 and 1.6%;
CO2 between 1.7 and 4.5%; 02 between 4.5 and 9%; C2H4
between 0.5 and 3.5%; and EDC at about 0.17%. Conversions
are typically for C2H4 - 88-99% and for HCl 99-100%.
Of the organic product, EDC comprises 98+% of each sample.
Run 6
Run 6 evaluated the effect of pure CO addition
in an amount approximately 2 times that which is normally
generated within the reactor. This was performed at 5.1%
excess ethylene.
Run 6 was performed at 5.1% excess C2H4, two
temperature levels, viz., 240 and 230°C, 60.3% excess
air, and with 2.0 gms/minute of CO added. Run 5, Period 1,
shows that the reactor produces 1.13 gms/minute of CO as
a reaction product. Run 6, Period 1, which occurs under
essentially the same operating conditions shows that
1.14 gms/minute CO is found in the vent gas. This shows
that the reactor was able to reduce the injected level of
2 gms/minute to some lesser value in conjunction with the
production rate normally occurring in the reactor. The
other components of the vent gas, conversions and product
yield do not appear to be adversely affected by the CO
addition.
Run 7
Run 7 evaluated the effect of pure C02 addition
in a sizable amount, viz., 5 gms/minute, which is about
equal to that normally generated in the reactor operated
at 5% excess ethylene.
Run 7 was performed with the addition of 5 gms/
minute of C02. The purpose of this run was to determine
how a higher C02 level in the reactor feed affected
catalyst, conversions, product distribution, and effluent
CO and C02 in the vent gas. In Run 7, Period 1, the vent
gas contained 6.57 gms/minute CO2 which is less than the
sum of the injected 5 gms/minute plus the normally
generated C02 in the reactor under identical operating
conditions, but without C02 addition. These results are
summarized below.
33
-------
Run 8
Run 8 evaluated the effect of pure CO addition,
this time, 6-8 times that which is generated normally
within the reactor.
Run 8 was performed at the same conditions as
Run 6, except that the CO rate was changed to 8 gms/minute.
The vent gas was slightly lower in 02 and N2; notably
higher in CO; higher in C02; and slightly higher in C2H4
when compared to Run 5 and Run 6. It was reasonable that
the 02 level should drop since 02 was used to oxidize CO
to C02. Also reasonable was the fact that the vent gas
was richer in CO and C02 since some of the CO from
injection was converted to C02« The effluent CO was
calculated to be 5.75 gms/minute which is again less than
that injected (8 gms/minute). Thus, the reactor did reduce
the CO level noticeably. The results of the CO runs were
encouraging in that they implied that CO oxidation was
taking place in the reactor and might therefore negate the
need for a CO oxidation unit.
High HCl breakthrough occurred in Run 8 causing
reddish brown, iron oxide corrosion product. Run 9 was
a baseline run to see if the system had returned to
normal operation after this large HCl breakthrough.
Run 9
Run 9 was a standard baseline run with 5.1% excess
C2Hx and 60.3% excess air with temperatures of 240°C and
230 C. The vent gas, for this run, was about one-half as
rich in CO and CO2 as compared to Runs 4 and 5. This
discrepancy is probably due to problems with the catalyst.
Run 10
Run 10 was a run in which 11 gms/minute C02 was
added to otherwise standard feed streams. The vent gas
for Period 2 contained 14.3 gms/minute of CO2 and was
slightly richer in C2H4 than without C02 addition. The
percent conversion for HCl and C2H4 remain respectively
greater than 99% and 94%. Performance seemed otherwise
quite adequate.
Run 11
Run 11 was a C02 run at 150 gms/minute imposed on
the standard baseline flows. It is equivalent to
operating with 63.4% inerts (CO2 + N2) or with 32% C02.
Unfortunately, the run does not give as much information
as desired since the superficial velocity was not main-
tained at the previously set value of 1.2 ft/second but
rather 1.77 ft/second. Also, temperature control was not
34
-------
very good in this run due to the high C02 flow. This
pointed to the need for a C02 preheater or a repiping
effort to feed the C02 through the air preheater.
The vent gas contained 140 gins/minute of CO2 which
shows a net decrease of C02 by the reactor. Even with
this high CO2 load, the conversions were still above
99% and 97%, for HCl and C2H4, respectively. It is
believed that excessive catalyst carryover occurred
during this run.
Run 12
Run 12 was a run which returned to the standard
baseline conditions, with just reactants and no additional
feeds. Again, the vent gas was very low in C02 and CO
(about 1/2 of Run 5, for example) and indicates a problem
in the catalyst bed. The bed was dumped and replaced
after this run in order to be sure of good data for the
following runs. It was noted however, that percent
conversions of HCl and C2H4 were quite nominal.
Run 13
Run 13 represented a baseline run with new
catalyst. It showed, for example in Period 1, a CO vent
gas composition of 0.9% and a CO2 vent gas composition
of 2.2% which are reasonably close to other baseline runs
with no problems in the run. Conversions were once again
nominal.
Run 14
Run 14 was another C02 run, but with 02 feed
instead of air. It was a better indicator of performance
than Run 11, since the flows were calculated to maintain
the 1.24 ft/second superficial velocity. This run
represents 46.3% C02 in the feed. Although the C02 was
preheated, the temperature control on the system was such
that the temperatures were a few degress low (236-238°C).
Unfortunately, since the vent rate was calculated by using
N2 as the tie substance, and the N2 contribution was due
only to purging, the vent rate is probably not very
accurate. There seemed to be no adverse effects to the
system from this high CO2 addition and conversion for
HCl and C2H4 remained above 99% and 95%, respectively.
Run 15
Run 15 was a CO run with an addition rate of
1.25 gms/minute. The vent gas for all periods for
35
-------
this run was richer in CO than the feed. For example,
Period 1 vent gas had 2.38 gms/minute of CO in it.
This can only be explained in terms of a lack of
equilibrium within the reactor. At some point, the
injected CO must have such a value that the effluent was
exactly the same value. Beyond this point, the system
reduces the level of CO below its entrance value. Once
again the yields were nominal.
Run 16
Run 16 was a high CO run, i.e., 12 gms/minute
for Periods 3, 4 and 5, which is more representative of
a recycle composition. The effluent in the vent gas
was 10.2 gms/minute for Period 4. The other values of
vent gas flow of CO gave rates which were all lower than
5 or 12 gms/minute CO, respectively. It appears that the
reactor oxidized CO to C02, but how efficiently still
remained to be answered. The conversions for this run
were still within the acceptable range, i.e., 95% and
greater.
Run 17
Run 17 represented a baseline run to determine
whether the reactor system could be returned to "normal"
after the CO addition. The data from that run was within
proper bounds when compared to previous similar runs.
At this point, it is well to point out that C02
appeared to have no adverse effect on the reaction and
that CO was oxidized to CO2 in the reactor as shown by
the data of Table 6. These experiments concluded the tests
using CO/C02 in the reactor feeds.
Run 18 was designed to study the effect of the
reactor on the hydrocarbon gases CH4 and C2H6.
Run 18
Originally, it was proposed to synthesize a recycle
gas which would contain CO, C02, CH4, C2H6, N2, 02, C2H4,
and HCl. Some of the guiding factors would be: 5% excess
C2H4, 70% excess O2, CH4/C2H6 = 2, C02/CO = 3, total
inerts = 40%, 40-60% CO+C02 in CH4 + C2H6. Such a mixture,
it was believed, would very likely duplicate the feed +
recycle stream in the proposed process. It was based on
assumptions that CH4 and C2H6 would build up in the recycle
stream as a result of impurities in the C2H4 feed stream.
The figures for CH4 and C2H6 in C2H4 feed streams are
36
-------
TABLE 6
SUMMARY OF CO ADDITIONS RUNS
CO Added in Feed
gm/minutes
CO Out in Vent Gas
gm/minute
Run/Period
2.0
ii
ii
ii
8.0
H
ii
ii
1.25
H
n
H
5.04
if
12.0
II
II
1.14
1.16
0.93
0.75
5.75
5.97
7.65
4.10
2.38
2.25
2.01
1.95
4.65
4.45
10.6
10.2
9.52
6,1
2
3
4
8,1
2
3
4
15,1
2
3
4
16,1
2
3
4
5
37
-------
average and rather high ones at that. Nevertheless, this
is what was decided.
In order to guarantee safety, detailed calcula-
tions on the flammability limits of the expected vent gas
were performed (see References 1, 2, and 3)*. These calcu-
lations led to the following results: the lower limit of
flammability was found to be 13% and the higher limit of
flammability was found to be 43% combustibles. Since the
% combustibles in the estimated vent gas would be 37%, the
vent gas would be explosive. Such a situation was clearly
unacceptable, sTrice the equipment does have glass pipe in
the vent legs and general operation under these conditions
was not desirable. The only way to deal with this vent gas
in this explosive range would be to add N2 to reduce the
combustibles below 13% or to add hydrocarbons to push the
combustibles above 43%. Either alternative was expensive
and it was decided to use another feed gas mixture.
It was reasoned that high percentages of CH4 and
C2H6 in the feed might not occur and also, it was not
known whether the reactor system would alter these gases
in any way. It was decided for simplicity and ease of
operation to return to an air run, i.e., 73% excess air,
9% excess C2H4 and use methane as 2% of the feed stream
and ethane as 1% of the feed stream (CH4 = 2.35 gm/minute;
C2H6 = 2.21 gms/minute). The reactor conditions were as
usual, 240°C and 230°C with all other variables the same
as previous runs.
The expected vent gas for this mixture was
evaluated in terms of its flammability limits with the
following results lower limit = 65%; upper limit = 76%.
Since the percent combustibles would only be 7%, there was
no danger of explosion.
The above mixture was run with the following
results: vent gas composition (typical); 028.6%, N2
81.8%, CH4 4.3%, C2H6 0.3%, CO0.7%, C02 2.2% and
C2H4 1.9%. This shows that the methane passed through
unchanged, but the ethane was reduced by 83% over the
inlet value. It can only be supposed that either the
ethane was oxidized or chlorinated in some way. This data
indicates clearly that methane will build up in the system
but that ethane will not. Yields were comparable with
previous baseline runs. Table 7 shows the results of
CH4/C2H6 additions.
* composition: 9% CO, 18% CH4, 9% C2H6, 1.5% C2H4, 10% 02,
and 52.5% N2 + C02.
38
-------
TABLE 7
RESULTS OF CH4/C2H6 ADDITIONS
Run/Period
18,1
2
3
4
5
CH4 Added in Feed
gms/minute
2.35
II
II
11
CH4 Out in Vent
gms/minute
2.53
1.97
2.84
2.19
2.57
C2H6 Added in Feed
gms/minute
2.21
n
ii
n
11
C2H6 Out in Vent
gms/minute
0.36
0.37
0.37
0.37
0.36
u
-------
Runs 19-26 involved post-chlorination of reactor
gases, i.e., a total of eight post-chlorination runs were
made. Of these, the first three (19, 20, 21) were not
quantitative with respect to chlorine analysis of the vent,
quench bottoms, or aqueous product. They were used mainly
to gain familiarity with the analytical techniques and
methods used in the chlorination runs. The computer out-
puts for these runs are incomplete. One run (#22) was at
12.9% excess ethylene in an effort to see the effect of
higher ethylene additions. All other runs were at 8%
excess ethylene with chlorine added in an amount which
was approximately stoichiometric with respect to the excess
ethylene. Runs 19, 20, 21, 22, 23 and 26 had the chlorine
injected into the head space above the bed and Runs 24 and
25 had the chlorine injected into the dilute phase of the
catalyst bed. It was decided to try both positions since
there are valid reasons for doing so. For example, it
was reasoned that injection in the dilute phase of the
catalyst (lower position) would lead to better conversion
since the residence time would be increased, the mixing
would be better, and the catalyst should help to promote
chlorination. This turned out not to be the case and the
details of the comparisons between the two positions was
reserved for discussion under Runs 25 and 26.
Analysis of chlorine in the vent was accomplished
by bubbling the vent gas through scrubbers containing 0.2 N
NaOH. The chlorine in the vent reacts to form hypochlorous
acid which can be determined by the standard lodometric
technique (4). The chlorine in the quench and aqueous
product were determined directly by the lodometric method.
It was also possible to measure the chlorine dissolved in
t he crude product by extracting the crude product with
water containing KI, titrating with sodium thiosulfate to a
light yellow, adding starch solution, and finishing the
determination by a final titration with thiosulfate from
a black to a colorless endpoint. This is the lodometric
method adapted to this immiscible system. The usual complete
analysis of the crude products was performed together with
gas chromatographic work on the vent gas. Thus, it was
possible to obtain a close material balance on the chlorine
and to use this to speculate on some unsuspected occurrences
in these runs.
Runs 25 and 26 are probably the most important of
all of the runs. Firstly, they were run as duplicates of
other runs, and secondly, they each had a baseline period
within the run so that the effect of chlorine addition could
be examined in the two following periods for a fixed
40
-------
temperature (240°C). These runs proved most elucidating
and will be discussed below in detail.
Runs 19, 20, 21
These runs were all at 8% excess C2H4, 72% excess
air with chlorine added in an amount which would approxi-
mately chlorinate the excess C2H4. Two temperature levels
were used: 240°C and 230°C. Quantitative data on chlorine
(only) was lacking in these runs. Also, chlorine was
injected into the head space. Discussion is deferred to
Run 26 (similar to 19, 20, and 21).
Run 22
This run was at 12.9% excess C2H4, 72% excess air
with chlorine added in an amount which would approximately
chlorinate the excess C2H4. One temperature level was
used: 240°C. If comparison is made to baseline Run #3
(10% excess C2H4, 60% excess air) it will be seen that
the average vent composition for C2H4 was 1.25%. Run 22
showed that the average vent composition for C2H4 was
reduced to 0.65%. Thus, it can be seen that post-
chlorination, in this case, had reduced the ethylene by
almost 50%.
Run 23
8% excess C2H4, 72% excess air with chlorine added
in an amount needed to chlorinate two-thirds of the excess
ethylene. Two temperature levels: 240°C and 230°C. See
Run 26 for details. This experiment was essentially the
same as Run 26, except that Run 26 was only conducted at
240°C. It may be briefly noted that the effect of tempera-
ture (10°C difference) was to reduce by 70% the effective-
ness of the post-chlorination. Injection was at the top
in the head space.
Run 24
Run 24 had 8% excess C2H4, 72% excess air with chlorine
added in an amount needed to chlorinated two-thirds of
the excess ethylene. Two temperature levels: 240°C and
230°C. See Run 25 for details. Injection of chlorine
was into the dilute phase of the catalyst. This experiment
was essentially the same as Run 25, except that Run 25 was
only conducted at 240°C. Here again, the effect of 10°C
drop in temperature to 230°C is to increase the ethylene in
the vent by 100% when compared to the 240°C run.
41
-------
Run 25
Run 25 had 8% excess C2H4/ 72% excess air. This
run had the first period as a baseline run with no chlorine,
and the last two periods with C12 at 3.66 g/minute. This
flow of chlorine would be sufficient to chlorinate 60+%
of the excess C2H4. Only the 240°C temperature level was
used. Such a run was the ideal way to see first hand how
the crude product, quench, aqueous product, and vent
changed within the same run as C12 was turned on.
The results of this run (made by carefully analyzing
Periods 1 and 2 and 1 and 3) lead to the following conclusions:
(a) A total material balance on C12 could not be
obtained. That is, approximately 45% of the
chlorine cannot be accounted for by analysis
of exit streams. The following hypothesis is
forwarded. The catalyst is composed of Cu2Cl2 and
CuCl2 in varying amounts. It is conceivable that
we were chlorinating the catalyst by injection
of chlorine into the dilute phase of the catalyst.
An analysis of the catalyst for Cu++ and Cu+ has
confirmed the shift in the valence of copper ion.
(b) virtually no chlorine showed up in the vent when
injection was into the dilute phase of the
catalyst.
(c) Some C12 did show up in the quench and aqueous
product under these conditions (none in crude
product).
(d) About 53% of the C12 injected was converted to EDC.
(Estimated by the increase in EDC product when com-
pared to first baseline period without C12 addition.)
(e) The C2H4 in the vent was reduced from 1.14% in
Period 1 (no C12) to 0.80% in Periods 2 and 3,
about a 30% reduction.
(f) The very high HCl titers in the quench and
aqueous product when compared to those when no
chlorine was added can be explained by the
following scheme: CO in the vent reacted with
C12 to form COC12 (phosgene). COC12 reacted with
water in the quench and aqueous product to form C02
and HCl. This HCl, increased very greatly the HCl
titer of the quench and aqueous product.
42
-------
(g) Ethylene conversion was increased by 1.2 percentage
points over the case of no chlorination in this run.
Run 26
8% excess C2H4, 72% excess air. This run had
Period 1 as a baseline run with no chlorine and the last
two periods with C12 at 3.67 g/minute. Again, this flow
of chlorine would be sufficient to chlorinate 60+% of the
excess C2H4. Only the 240°C temperature level was used.
Such a run was the ideal way to see first hand how the
system reacted to the chlorine injection within the same
run. Chlorine was injected into the head space.
The results of this run (made by carefully
analyzing Periods 1 and 2 and 1 and 3) lead to the
following conclusions:
(a) A total material balance on C12 could be obtained
to within 3%. It thus substantiates the con-
clusion of Run 25 that the chlorine was reacting
with the catalyst since in this run the chlorine
injection was above the catalyst.
(b) Chlorine did show up in the vent in this run.
Approximately 25% of the chlorine injected
could be seen in the vent.
(c) Larger quantities of C12 were found in the
quench and aqueous product than in Run 25;
roughly ten times more than in Run 25.
Also, a significant amount of C12 was found
dissolved in the crude product (about 1% of
the injected amount).
(d) Approximately 67% of the injected chlorine
reacted to form EDC. This is significantly
better than the 53% from Run 25.
(e) The ethylene in the vent was reduced by 75%
over Period 1 with no chlorination.
(f) The very high HCl titers were still present in
this run as in Run 25 and the same scheme is
surmised to apply, viz., the generation of
phosgene with the consequent reaction with
water to form C02 and HCl.
(g) Ethylene conversion was increased by about 1.8
percentage points over the case of no chlorina-
tion, in this run.
43
-------
Thus, it appears that all is not so simple in
post-chlorination, and that the better result appears to be
achieved at the upper location in the head space due to
a competing reaction of C12 with the catalyst at the lower
location. Better conversions are apparent at the upper
injection port, but C12 does appear in the vent, waters,
and crude product and would have to be dealt with
especially in regard to corrosion problems.
RECYCLE PROCESS
The variables which were important for recycle
operation were: (Note: They are not all independent.)
HCl feed rate Ibs/hr determined capacity
of "plant".
% excess O2
Reactor temperature, °C
Reactor pressure, psig
Superficial velocity, ft/second
Recycle rate mole/time or Ibs/time
N2 purge rate needed for proper functioning
of pressure taps but also could simulate the
N2 present in commercial 95-99% pure 02.
Impurities in the C2H4 feed (viz. CH4 or C2H4)
or CH4 additions to simulate such.
Of the above variables, the ones which were not
independent (in terms of constant capacity or production
and constant temperature) were:
Reactor pressure, psig
Superficial velocity, ft/second
Recycle rate Ibs/time, moles/time
The reasoning was as follows:
Gases
EDC + H20
Fresh
Feed
HCl
C2H4
Total Feed
Recycle .. Some C2H4, CO, C02, N2, 02, (HC?)
44
-------
For a given feed of HCl in Ibs/time or Ib moles/
time, the capacity or production rate of the system would
be fixed. The total feed in Ib mole/time, the reactor top
pressure, and the superficial velocity would be determined
by the reactor cross-section and the ideal gas law. At
steady-state, the fresh feed + recycle = total feed. For
fixed HCl rate, the amount of 02 and C2H4 in the fresh feed
would be determined by the recycle composition and recycle
rate. Therefore, the recycle rate will have only one
possible value at set conditions of superficial velocity,
% excess ethylene and reactor pressure. If we change the
reactor pressure, but require that the superficial velocity
be maintained constant (along with all other variables),
then the only thing which can vary would be the recycle
rate. This immediately implies a given vent rate since
the production of off-gases would be determined by the
HCl rate (capacity). Thus, the amount vented will be
fixed at a given fresh feed rate, reactor pressure,
% excess C2H4, and superficial velocity. Consequently,
the emissions will be directly related to this vent rate
and its hydrocarbon composition.
The above reasoning then led to the conclusion
as to the types of experiments to carry out and the
variables to change most easily for experimental work.
It appeared that the superficial velocity and recycle rate
could be adjusted (i.e., one or the other) while other
conditions were maintained constant. In this way, we could
develop a set of experiments to be performed.
The analysis of data will be aided by the
following idea. One can define an "efficiency", 17, which
is given by
/ \ / \
(EHc)EX- (EHc
= _J> - /EX . \ - L
(£)
y HC/
T, = _> - . - L- (6)
EX
Mass of Total Hydrocarbons Emitted
lb EDC P5o3uced
in existing once through systems, and
lb Mass of Total Hydrocarbons Emitted
lb EDC Produced
in the recycle system.
45
-------
Clearly, 17 = 0 implies that the recycle process is
emitting just as much HC/lb EDC produced as the original
once-through process. *) = 1 implies no hydrocarbon at all
is being vented. The objective of this project was to
reduce by 90% the emissions from the existing process. This
would correspond to 17 = 0.9. Negative values of 17 would
imply that the recycle process is emitting more than the
existing once-through process.
In terms of useful graphical plots, it would seem
useful to plot TJ vs. the % recycle rate for constant
temperature, pressure, HCl rate, % excess C2H4< and %
excess 02. Here percent Recycle Rate = R/(R + V), where
V is the vent rate in Ib moles/second and R is the recycle
rate in Ib mole/second. Such a plot should be expected to
increase monotonically from "H = 0, R/(R + V) = 0 to
T) = 1, R/(R + V) = 1. The point where = 0.9 would yield
the minimum recycle rate necessary for 90% reduction of
hydrocarbon emissions. It would also be possible to obtain
families of curves which would depend on such parameters as
reactor temperature, % excess ethylene, and % excess oxygen.
Thus, operating data of flow rates, feed compositions, and
reactor conditions would indicate where emissions would be
more than 90% reduced.
Also useful would be plots of emissions in
kg(HC + EDC)Ag HCl vs. % excess C2H4 with reactor tempera-
ture as parameter. Plots such as this for both once-through
and recycle would then enable the plotting of 17 vs. % excess
ethylene with reactor temperature as parameter.
The choice of final operating conditions will
always depend on the determination of the best economics.
As in the once-through runs, the quench bottoms, aqueous
product, crude product, and the vent gas were analyzed.
Operating Data and Calculated Data for the recycle process
are shown in Tables 2 and 3 in the Appendix.
It will be seen that all recycle runs were conducted
at 10 Ib/hour HCl with 45 psig reactor pressure and 223°C
to 252°C reactor temperatures. Also, all runs had 90% or
greater of the off-gases recycled. Superficial velocities
were maintained at 1.1-1.2 feet/second. Processing of the
data was effected by means of a computer material balance
program*. Sixteen recycle runs were made, most with four
periods of one hour each. One of these runs was a standard
once-through run which was performed to verify the system's
consistency.
* Results available on request from Industrial Environmental
Research Laboratory of EPA.
46
-------
Table 8 gives the outline of the recycle experi-
ments conducted in this work.
47
-------
TABLE 8
Outline of Experimental Runs Obtained on Low Emissions
Oxyhydrochlorination Recycle Operation with Oxygen Feed
(All at 45 psig Reactor pressure, 1.2 ft/sec Superficial
Velocity and 10 Ibs/hr HCl Rate.)
Run #
R100
R101
R105
R106
R107
R108
R109
R110
Rill
Number
of Periods
2
4
1
2
4
4
4
4
3
Temperature
Range, °C
244-246
242-250
242
241-243
241-244
239-244
240-243
249-251
251-254
% 02
in Vent
(O, Meter)
5.3-7.6
0.23-3.9
2.7-3.9
2.4-6.0
0.34-1.15
0.75-1.4
4.2-9.1
0.26-0.53
4.6-7.2
Approximate
% xs O2
to Reactor
57-83
52-83
68
60-77
75-86
56-95
71-115
68-74
100-110
% C2H4
in Vent
(.CyH* Meter)
5.3
0.7-1.0
1.0-1.1
1.4-2.0
3.4-4.9
1.4-2.0
0.95-1.40
0.65-1.5
0.6
Approximate
% xs
C2H4 to Reactor
14-22
5-8
0
10-11
16-31
11-12
9-13
10-13
12
00
-------
TABLE 8
(Continued)
Outline of Experimental Runs Obtained on Low Emissions
Oxyhydrochlorination Recycle Operation with Oxygen Feed
(All at ~45 psig reactor pressure, 1.1-1.2 ft/second Superficial Velocity,
and 10 Ibs/hour HCl Rate.)
Run #
R112
R113
R114
R115
R116
R117*
R118
Number
of Periods
3
4
4
1
4
4
1
Temperature
Range, °C
251-252
230-231
230-232
238
229-232
230-242
223
% 02
in vent
(Oa Meter)
0.22-0.36
6.9-8.2
0.22-0.36
6.6
2.1-6.1
5.3-7.0
12.6
Approximate
% xs O2
to Reactor
76-78
55-74
60-71
83
49-78
70.1
77.9
% C2H4
in Vent
(C2H4 Meter)
2.5-3.3
3.4-3.7
2.8-3.4
1.2
3.4-4.8
0.6-1-6
3.4
Approximate
% xs
C2H4 to Reactor
17-20
12
9-13
8.4
14-19
5.3
4.6
* Baseline Run Once-through Operation
-------
SECTION VII
RESULTS
ONCE-THROUGH PROCESS
Figure 9 shows how wet EDC purity wt.% varied
with reactor temperature. This inversely linear behavior
indicates that lower reactor temperatures will be more
attractive economically since purification costs will be
lessened. The least squares fit of this data is given
by:
EDC0 = 112.31 - 5.78(10~2)T (7)
Where EDCO = Wet EDC purity Once-through in wt.%
T = Reactor temperature, °C
The standard error of estimate for (7) is 0.226.
Figure 10 shows the kg(HC + EDOAg HCl vs.
% excess ethylene with reactor temperature as parameter.
The fitting lines were obtained by the following
procedure: all emission data for the once-through process
(at all temperatures) were fit vs. % excess ethylene. This
yielded a slope for all the data. Then, this slope was
used to re-fit the data at the two temperature levels of
230°C and 240°C vs. % excess ethylene. In this way,
consistent correlating lines could be obtained with
temperature as parameter.
The results of correlation of emissions data from
the once-through process are:
(Mean - 231°C) EMo = 2.47(10~2) + 1.35(10-3) XSETH (8)
(Mean - 240°C) EMo = 1-32(10-2) + 1.35(10~3) XSETH (9)
Where
EMo = Emissions in g^C * ? for once-through
Kg HC1 operation.
XSETH = Percent excess ethylene to reactor.
50
-------
01
99-0-
PH
O
Q
98.0
97. n_
225
00
+00.
230
2UO
REACTOR TEMPERATURE °C
FIGURE 9:
WET EDC PURITY-
(ONCE-THROUGH PROCESS)
VS.
REACTOR TEMPERATURE °C
j- POST-CHLORINATION
RUNS
250
-------
0.07-
o.oo
0.05-
wi
I
CO °"'
§
H
CO
CO
H
0.03-
w
+
0.02
0.01
FIGURE 10:
TOTAL HC + EDC EMISSIONS
Kg/Kg HC1
VS.
% EXCESS ETHYLENE (ONCE-THROUGH)
WITH
REACTOR TEMPERATURE AS PARAMETER
O
O
O231°C MEAN
A240°C MEAN
0
10 15
% EXCESS ETHYLENE
52
20
-------
RECYCLE PROCESS
Figure 11 illustrates the variation of wet EDC
purity (wt. %) with reactor temperature. Again, the
purity varies inversely with temperature. Also plotted is
the least squares line for the once-through process. Thus,
it can be seen that the product purity in the recycle
operation is a few tenths of a percentage point lower than
the once-through purity at the same temperature. This fact
should be taken into account in any economic considerations.
The correlating least squares line for EDC
purity is given by:
EDCp = 109.6 - 4.91(10-2) T
(10)
Where EDCR = Wet EDC purity wt. % in recycle operation
T = Reactor temperature, °C
Standard Error of Estimate = 0.232
Figure 12 is the correlation of emission data,
kg(HC + EDC)Ag HC1 vs. % excess ethylene with reactor
temperature as parameter. Once again, all the emission
data was fit vs. percent excess ethylene (for all tempera-
tures) to obtain a slope for all the data. Then, the slope
was fixed and the data for the three temperature ranges
230, 240, 250°C was re-fit vs. % excess ethylene. This
yielded consistent correlating lines with temperature as
parameter.
The results of correlation of emission data from
the recycle process are:
(Mean - 230°C) EMR = -1.08(1Q-4) + 2.05(10~4) XSETH (11)
(Mean - 242°C) EMR = -6.45(10~4) + 2.05(10-4) XSETH (12)
(Mean - 251°C) EMR = -8.03(1Q-4) + 2.05(10~4) XSETH (13)
Where
EMR = Emissions in Kg(HC + EDC) for reCyCie operation.
K Kg HCl
XSETH = Percent excess ethylene to reactor.
53
-------
FIGURE 11:
WET EDC PURITY-
VS.
REACTOR TEMPERATURE °C
(RECYCLE DATA)
99-
01
*>.
H
PL,
B 98. a
w
H
97.0
220
ONCE-THROUGH-LEAST SQUARES FIT
DATA
RECYCLE DATA LEAST SQUARES
FIT
o o
o o
230
240
250
REACTOR TEMPERATURE C
-------
co
§
H
CO
SO
O
Q
W
O Wl
EH
O
EH
0
FIGURE 32:
TOT£L HC + EDC EMISSIONS - Kg/Kg HC1
VS.
% EXCESS ETHYLENE
WITH
REACTOR TEMPERATURE AS PARAMETER
RECYCLE PROCESS
FIT
PIT
FIT
O 230°C MEAN
A 242°C MEAN
+ 251°C MEAN
10 15
^ EXCESS ETHYLENE
20
-------
COMPARISON OF EMISSIONS FROM ONCE-THROUGH AND RECYCLE
If one compares the emissions from the once-
through and recycle operation at the same reactor
temperature and percent excess ethylene, the following
table results:
TABLE 9
COMPARISON OF EMISSIONS DATA
RECYCLE AND ONCE-THROUGH
Table entries show % reductions in emissions -f)
of recycle process compared with once-through
process at similar values of % excess ethylene
and reactor temperature, T°C.
% Excess Ethylene
5
10
15
20
230°C
97.2
95.1
93.6
92.4
240°C
97.4
94.2
92.3
91.1
This result is also shown in Figure 13. Thus,
it can be seen that the original objective of this
investigation, viz., the reduction by 90% of the emissions
from the EDC process through implementation of a recycle
scheme has been positively demonstrated.
SELECTION OF OPTIMUM OPERATING CONDITIONS
The following trends and facts were used in the
selection of the optimum operating parameters:
(a) Crude product (EDC) purity varies in a
linearly inverse manner with reactor
temperature, i.e., a lower operating
temperature yields higher crude EDC
purity.
(b) It appears that the crude EDC purity for the
recycle operation lies a few tenths (0.5-0.7)
of a percentage point below the crude EDC
purity for once-through operation at any
temperature.
56
-------
100,
CO
§
H
co
co
M
H
a;
H
g
EH
3
W
g
H
PL,
90
FIGURE 13:
- PERCENT REDUCTION IN EMISSIONS
RECYCLE COMPARED TO ONCE-THROUGH
VS.
% EXCESS ETHYLENE
WITH
REACTOR TEMPERATURE AS PARAMETER
FOR R/R+V ^0.9
SUPERFICIAL VELOCITY 1.? ft/sec
EXCESS OXYGEN - 50$ TO 100$ +
R = RECYCLE RATE
V = VENT RATE
30 °C
6 8 10 12 1
% EXCESS ETHYLENE
16 18
20
Most commercial plants operate at 50-70% excess
air and 5-10% excess C2H4.
57
-------
(c) Ethylene efficiency decreases with higher
operating temperature. Efficiency is
defined as
C2H4 Converted to EDC/C2H4 Fed.
(d) Ethylene efficiency for the recycle process
is higher than for the once-through process
due to the reduced loss of ethylene in the
vent. So also is the oxygen efficiency.
(e) All runs involved recycling greater than
90% of the off-gases.
(f) The comparison between emissions from the
once-through process and the recycle
process requires a matching of respective
operating conditions.
(g) It appears that 230°C forms the lower bound
of temperature for trouble-free running of
the recycle system.
(h) The minimum excess ethylene consistent with
ease of operation, catalyst fluidization,
and HC1 breakthrough appears to be 5-7%.
(i) The minimum excess oxygen consistent with
(h) appears to be about 50%.
The selection of optimum operating conditions
in light of the above became dependent on ease of operation
and on the conditions which maximized purity and ethylene
efficiency. Thus, we found that the minimum in terms of
operating costs will occur at the lower temperature
boundary of our operating range, viz., at or around 230°C
with 5-7% excess ethylene and with 50-60% excess oxygen.
58
-------
SECTION VIII
COMPUTER SIMULATION AND ECONOMIC STUD?
COMPUTER SIMULATION
In an effort to have a rational method for scale-
up of the results from the pilot plant work to a size repre-
sentative of a commercial unit, a simulation computer
program was developed.
The program consisted of a cyclical material
balance scheme which utilized experimentally observed
gas generation rates within the pilot plant recycle
system (i.e., for CO, CO2). The program had the
capability of adjusting feed rates, reactor pressure and
temperature, % excess ethylene, % excess oxygen, and the
superficial velocity in the bed. Also, by varying the
holdup time in the recycle system, various approaches to
steady state could be achieved. The output consisted of
the recycle rate, vent rate (both in kg mol/hour), %
recycled, HC + EDC emissions in kg/kg HCl and the complete
vent composition.
As an illustration of the effectiveness of
this program in duplicating results, Table 10 is presented.
The close correspondence of the simulation to the labora-
tory data is apparent.
An added feature of ths program was the ability
to imput CH4 and/or C2H6 in the feeds to simulate their
effect on the vent. Data obtained on the once-through
process was used to estimate the reactor's effect on C2H6.
The effect of CH4 in the feed C2H4 and C2H6 in the feed
C2H4 on the % HC emission reduction is shown in Figures 14
and 15, respectively.
Figure 14 shows that CH4 can create a problem by
building up in the recycle stream. In fact, 0.5% or greater
CH4 in the C2H4 feed would cause the HC emissions reduction
to slip below 90%. The project objective is to maintain
at least 90% reduction. The worst case economically
(actually used below) is that the vent gas contains CH4,
but not enough to be flammable without the addition of
natural gas. Percentages of methane in the feed greater
than 2% are already flammable by mixing with air and thus
can be flared quite easily.
59
-------
TABLE 10
COMPUTER SIMULATION
Reactor Temperature 230.6°C
Reactor Pressure 44.9 psig
Superficial Velocity 1.141 ft/sec
Excess Ethylene 13.8%
Excess Oxygen 63.6%
Recycle Rate
(KG m
Vent Rate
(KG m
% Recycled
HC and EDC Emissions
(KG/KG HCl)
Vent Composition (%)
02
N2
CO
C02
C2H4 -
C2H6
EDC
N2 + C02
Laboratory Data
0.1695
0.0074
95.82
0.0022
5.16
13.98
2.01
75.17
3.13
0.10
0.46
89.15
Simulation
0.168
0.0077
95.58
0.002
6.74
2.22
2.035
84.89
3.61
0.095
0.40
87.11
60
-------
100
O 80
-U
o
O
0)
c
o
H
cn
(0
-i-i
W
60
40
20
FIGURE 14: % HYDROCARBON7 EMISSIONS REDUCTION"
VS.
% CH^ IN C2Hii FEED
5 10
% CH4 in C2H4 Feed
15
-------
98
FIGURE 15: % HYDROCARBON EMISSIONS REDUCTION VS.
% C2Hg IN C-Hj, FEED WITH OXYGEN PURITY
AS PARAMETER
97
c
o
-H
-p
(0
e
0)
CO
H
c
o
A
H
rt
u
O
96
95
94
93
92
100% 02
91
90
10
C2H6 in C2H4 Feed
-------
Figure 15 shows that the effect of C2H6 is very
much less and would probably not create any difficulty
since even for oxygen purities as low as 90%, all % HC
emissions reduction remain above 90% for C2H6 from
0-10% in the feed.
With these results available and the computer
simulation program capable of handling scale-up of our
system, an economic analysis was performed.
ECONOMIC STUDY
The economic study had for its basis the
following:
7% excess C2H4 to the reactor
50% excess 02 to the reactor
98% pure C2H4 (2% CH4)*
95% pure 02 (5% N2)
700 MM Ibs/year EDC capacity
The study involved an Incremental capital Cost
Comparison and an Incremental Manufacturing Cost Comparison
using the conventional process with air feed as the basis
system. The costs necessary to convert to a recycle process
with 02 feed are outlined in Table 11 and 12. The result
is that the recycle process becomes competitive with only
a nominal increase in the cost of EDC/lb. Figure 16 shows
how the incremental manufacturing cost in $/Ib EDC varies
with oxygen cost/NT and ethylene cost/lb. As ethylena
becomes more expensive, the recycle process becomes more
attractive due to its inherent higher efficiencies.
Thus, the original objective of this project has
been met, viz., the development and demonstration of a
recycle process for ethylene oxyhydrochlorination which will
reduce by at least 90% the HC + EDC emissions over existing
processes. Also, economic competitiveness for the recycle
process compared to the conventional process appears fairly
well demonstrated.
* Note: 2% CH4 in C2H4 will mean that 90% reduction in
hydrocarbons cannot be achieved, a priori. This
is the economically more stringent case which (in
the following economic analysis) demands that
natural gas (CH4) be added to the vent to make it
combustible and then burning the vent gas in a plume
burner.
63
-------
TABLE 11
INCREMENTAL CAPITAL COST COMPARISON
OXYHYDROCHLORINATION SYSTEMS FOR PLANT
TO PRODUCE 700 MM LB/YR EDC
Case
Description ^cycle Process
Air Feed 2
Capital Costs - M$*
Air compressors & aux. $ 650 $
Recycle compressors &
aux. - 250
EDC absorption &
stripping 375 50
Vent plume - 50
Major Equipment $ 1,025 $ 350
Erection 115 40
Process piping 410 140
Foundations & Supports 175 60
Power wiring 100 35
Instrumentation 110 90
Paint & Insulation 50 20
Direct cost $ 1,985 $ 735
Engineering, contingency
& overheads 1,150 425
Total Cost* $ 3,135 $ 1,160
Escalated to 1977 $ 3,450 $ 1,280
* These costs cover only those items which are not
the same in the two alternate systems.
64
-------
TABLE 12
INCREMENTAL MANUFACTURING COST COMPARISON
OKYHYDROCHLORINATION SYSTEMS FOR PLANT
TO PRODUCE 700 MM LB/YR EDC
Conventional
Process
Air Feed
3,300
Case
Description
Fixed Capital - M$
Manufacturing Costs -M$/Yr*
Raw Materials & Utilities
Oxy feed C2H4 at $200/NT $ 21,997
Oxy feed 02 at $24/NT
Nat. gas to plume at
$1.25/MCF
Electric power at
$15/MKWH 254
Steam for stripping
at $3.75/NT 22
Manufacturing Expense
Maintenance & supplies
at 7% of F.C.
Depreciation - 10% of F.C.
Taxes & insurance
242
345
35
Total cost $ 22,895
25% ROI 863
Total Cost* $ 23,758
Incremental cost difference
Unit cost cj:/lt> EDC
Recycle Process
02 Feed
1,280
$ 21,319
1,821
50
48
2
90
128
13
$ 23,471
320
$ 23,791
93
0.0047
* These costs cover only those which are not the
same for the two alternate systems.
65
-------
o
0.08i
O.Ob.
0.04-
0 . 02 «
EH
CO
o 0.00+
-0.02.
w
«
o
z,
H
-0.04.
-0.06-
FIGURE 16:
EFFECT OF OXYGEN AND ETHYLENE COSTS ON
INCREMENTAL MFG. COST FOR RECYCLE
OXYHYDROCHLORINATION PROCESS VS. CONVEN-
TIONAL PROCESS-BASIS: 700 MM Ib/YR EDC
30
-0.08
10 11 12
ETHYLENE COST -
66
13
-------
SECTION IX
REFERENCES
1.
2.
3.
4.
5.
Coward, H. F. and Jones, G. W. Limits of
Inflammability of cases and vapors. Bureau of
Mines Bulletin. Washington, D.C. #279. 1939.
Ash, S. H. and Felegy, E. W. Analysis of Complex
Gas Mixtures. Bureau of Mines Bulletin. Washington,
D.C. #471. 1948.
Coward, H. F. and Jones, G. W.
Flammability of Gases and Vapors.
Bulletin. Washington, D.C. tt?in3
Limits of
Bureau of Mines
#503. 1952.
Standard Methods for the Examination of Water and
wastewater. 13ed. APHA-AWWA-WPCF. New York. 1971.
Houdry report. Indepth Study of VCM Production.
Contract No. 68-02-0255 for EPA by Houdry Division,
Air Products and Chemicals, Inc., P.O. Box 427,
Marcus Hook, PA 19061. Revised, 20 June 1975.
67
-------
SECTION X
LIST OF INVENTIONS
Disclosed in U. S. Application Serial
Number 587,781, filed on June 17, 1975 by vT. S. Amato,
B. Bandyopadhyay, B. E. Kurtz, and R. H. Fitch for
Cyclic Ethylene Oxyhydrochlorination Process with
Reduced Hydrocarbon Emissions.
68
-------
SECTION XI
GLOSSARY
Quantity of Reactant Into Process
Conversion = Quantity of Reactant Out of Process
Quantity of Reactant Into Process
Yield
Amount of Reactant Converted to
Desired Product
Amount of Reactant Converted
Amount of
Reactant Converted to
__. . _ . . ,, Desired Product
Efficiency = Conversion x Yield = Amount of Reactant
Fed to Process
HC - Hydrocarbons
OHC - Oxyhydrochlorination
EDC - Ethylene dichloride
Ortho - Orthodichlorobenzene (Dowtherm E)
69
-------
SECTION XII
APPENDIX
Page
Table 1 Operating and Calculated
Once-Through Data 71
Table 2 Operating Data Recycle Process 77
Table 3 Calculated Data
Recycle Process 83
70
-------
Appendix
Table is Once-Through Operating and Calculated Data
Run #, Period
1. 1
3
2. 1
2
3
3. 1
2
3
4
4. 1
2
3
4
5. 1
2
3
4
6, I
2
3
4
7. 1
2
3
4
8. 1
2
3
4
9. 1
2
3
4
10. 1
2
3
4
11. 1
2
12, 1
2
13, 1
2
3
4
Date
9/5/74
«
9/11/74
"
ti
9/13/74
«
"
It
9/16/74
11
"
it
9/17/74
11
»
n
9/19/74
11
11
9/23/74
11
11
11
9/26/74
"
ii
10/11/74
"
"
"
10/16/74
11
11
"
10/18/74
"
10/18/74
"
10/21/74
"
n
i
-------
Appendix
Table 1:
Once-Through Operating and Calculated Data
(Continued)
Run #, Period
14. 1
2
3
4
15. 1
2
3
4
16. 1
2
3
4
5
17. 1
2
3
4
18. 1
2
3
4
5
22. 1
2
23. 1
2
3
4
24, 1
2
3
4
25. 1
2
3
26, 1
2
3
Date
10/24/74
II
11
11
10/29/74
"
"
11
10/31/74
11
11
"
"
11/4/74
11
11
11
11/27/74
n
u
12/13/74
"
12/16/74
11
11
11
12/18/74
11
"
11
12/23/74
"
"
12/30/74
11
Temperature
& Pressure
T "C
240
23-1
235
236
237
237
2JO
228
240
241
231
2 ID
240
240
212
230
230
250
240
237
230
238
241
238
240
241
230
230
240
237
232
233
240
240
240
240
241
240
P psi
-------
Appendix
Table 1:
Once-Through Operating and Calculated Data
(Continued)
Run #, Period
1, 1
2
3
2. 1
2
3
3. 1
2
3
4
4. 1
2
3
4
5. 1
2
3
1
6, 1
2
3
4
7. 1
2
3
4
8, 1
2
3
4
9. 1
2
3
4
10. 1
2
3
4
11. 1
2
12. 1
2
13. 1
2
3
4
Aqueous
Product
gins/period
640
56 0
580
1240
1250
1220
1200
1220
1200
1140
1150
1180
1300
1110
1220
1150
1080
1U-1U
1700
1220
1190
1100
1180
1140
1100
10-10
1260
1200
1200
1160
1140
11BO
1100
1100
1200
1160
1140
1140
920
740
1110
1110
1220
1220
1120
1110
Quench
Bottoms
gins/period
1021
1430
1300
1663
1612
1774
1820
1523
1272
1490
1824
1543
2044
1358
1205
1870
1764
2340
1760
1762
1800
1720
1466
1533
1703
1*180
1576
1874
I'Jbt)
1898
1864
16JO
2240
1720
1672
2220
1398
1654
1034
1240
1934
1754
1824
1473
1874
1884
Quench
Water
gras/minute
44.5
49.5
49.5
30.0
30.0
30.0
30.0
(
36.0
30.0
N2 Purge
Rate
gins/minute
4.27
4.27
4.27
2. 64
2.64
2.64
3.42
3.42
3.42
3.42
3.43
3.42
3.42
3.42
3.43
3.43
3.43
3.43
4.29
,
4.26
4.26
4.26
4.26
4.29
4.26
i
HC1 in
Decanter
H20
qmq/poriod
0.047
0.041
O.021
O.IK1U
0.070
0.060
0.060
0.050
O.OGO
O.070
0.080
0.090
0.090
0.120
0.067
0.063
o.mo
0.076
0.120
0.090
0.040
O.O80
0.120
0.100
o.nso
0.070
0.110
0.110
0.110
0.100
O.O8T
0.086
0.060
O.OGO
0.087
0.085
0.125
0.125
0.121
0.081
0.081
0.160
0.089
0.089
0.090
0.081
I1C1 in
Quench H3O
gins/period
0.186
0.156
0.142
0.420
0.440
1.03
0.62O
0.610
0.500
0.65O
1.05
1.68
5.43
10.8
1.27
1.57
1.73
1.96
2.82
2.89
2.63
2.70
7.66
5.19
3.10
3.25
1.95
1.S4
2.43
2.89
5 . .1C
13.29
2.70
2.70
3.23
4.13
14.19
39.65
6.72
3.26
5.21
22.02
1.79
1.66
3.88
4.80
Vent Gas
Rate
gin- moles
minute
4.02
3.98
4.03
3.72
3.73
3.73
3.76
3.69
3.72
3.84
3.69
3.71
3.75
3.79
3.70
3.70
3.77
3.75
3.69
3.75
3. 81
3.82
3.84
3.82
3.01
3.99
3.96
3. OS
4.08
3.86
3. 80
3.87
3.79
3.77
4.02
4.02
4.07
4.12
6.94
6.93
3.80
3.79
3.74
3.77
3.81
3.82
% oa
4.60
4.39
6.08
5.GU
2.90
3.49
5.29
2.20
9.38
5.9U
5.49
6.19
8. -19
9.18
5.20
5.19
7. 60
7.79
4.59
6.60
7.T.O
8.49
7.49
5.79
B.r.n
9.88
4.29
1.80
6.10
6.89
9.PH
11.08
6.99
G.V)
5.09
6.49
8. IB
10.39
4.89
4.79
9.27
8.38
5.20
5.90
8.49
8.59
1 Hj
87 . 8-1
88.65
87.56
88. US
88.55
88.65
88. G6
90.25
86.65
H8.U5
90.36
89.85
88.84
87.95
90.14
90.15
HH.HI
88.84
91.05
89.54
8H.15
8B.05
87.45
88.05
HT.n.'i
84 . 1 6
84. 9G
SI 1 I
82.44
87.15
as. 3.1
83.75
88.75
K'l.O'i
83.47
83.56
82.58
81.54
48.42
48.52
88.46
88.66
89.94
89.04
88.15
87.95
% CO
1.30
1.00
1.00
1.10
1.90
1.60
1.30
1.40
0.60
O.UU
1.10
1.20
0. 10
0.70
1.10
1.10
o.uo
0.60
1.10
1.10
0.10
0.70
0.80
0.80
0.1,0
0.30
5.19
5. 10
6.70
3.79
o.r>o
0.50
O.GO
0.70
0.90
0.70
0.40
0.10
0.20
0.20
0.40
0.40
0.90
1.00
0.40
0.40
1 CO,
3.40
2.60
1.70
2.99
3.99
3.89
3.59
4.49
1.90
2.60
2.49
2.10
0.70
0.60
2.90
2.70
I.JO
1.30
2.60
2.20
l.GO
1.30
3.89
4.69
J . u'J
2.10
4.29
5 . Oil
2.40
1.00
l.OO
0.90
1.60
1.50
9.18
8.09
6.78
5.80
45.92
46.02
0.80
0.90
2.20
2.50
0.90
0.60
%
C,H4
2.70
3.19
3.40
1.20
2.50
2.20
1.00
1.50
1.30
2.00
0.40
0.50
1.40
1.40
0.50
0.70
I.JO
1.30
0.50
0.40
1.50
1.30
0.20
0.50
1.30
2. SO
1.10
o r>o
2.20
1.00
O.-IO
0.60
1.90
2.OO
1.20
1.00
1.89
2.00
0.40
0.30
0.90
1.50
l.GO
1.40
1.90
2.30
1 CH«
u
-------
Appendix
Table 1;
Once-Through Operating and Calculated Data
(Continued)
Run #, Period
14. 1
2
3
4
15. 1
2
3
4
16, 1
2
3
4
5
17. 1
2
3
4
18. 1
2
3
4
5
22. 1
2
23, 1
2
3
4
24. 1
2
3
4
25, 1
2
3
26. 1
2
3
Aqueous
Products
gins/period
J?r,o
1240
1240
1240
12*10
1240
1120
1090
1240
1220
1220
1220
1220
1200
121O
1100
1130
1180
12-10
12SO
1120
1100
1J20
1330
1210
1230
1130
1130
1180
10-10
1140
1100
1200
1160
1140
1320
1290
1360
Quench
Bottoms
gins/period
1 ',00
1222
1600
1600
1533
1242
1625
188-1
1603
1643
1R24
IVd-l
1794
1802
no2
1784
1854
1780
OHO
1563
1900
1700
2016
1994
1508
1518
1735
1767
1X24
1673
1827
1973
1902
1902
18-14
1222
1539
1271
Quench
Water
gins/minute
30.0
N2 Purge
Rate
gins/minute
4.29
I
*
F
4.28
1
1
T
4.26
1 '
4.29
4.28
4.26
4.26
4.29
4.29
4.26
HC1 in
Decanter
H20
gins/per lod
0.i:'2
0.270
0.270
O.317
0.090
0.090
0.080
0.080
0.090
0.111
0.080
0.1JJ
0.089
0.090
o. i:iu
0.120
0.120
0.086
o.oyo
0.091
0.082
0.120
2.74
2.81
1.37
1.48
2.10
2.14
0.172
0.152
0.332
0.201
O.C
0.127
0.125
o.:
0.04
1.09
0.075b
0.075
0.009
0.009
0.012
0.012
o.noi
0.004
0.002
0.002
88
0.002
0.002
4
0.046
0.116
HC1 in
Quench IlgO
gins/period
2.19
2.09
1.93
1.R1
2.79
4.16
5.14
5.11
4.14
4.07
2.99
3.14
2.94
2.04
2 . 19
4.09
3.78
2.66
2.14
2. 1C
2.84
2-'>'>
20.79
23.25
13.18
13. 10
12.33
13.03
8.76
11.26
47.44
57.45
1
5.75
T.no
2
14.62
17.09
0.035C
0.020
0.016
0.016
0.0-17
0.050
O.OriS
0.059
0.294
0.220
99
0.027
O.O2G
45
0.184
0.138
Vent Gas
Rate
gin-moles
minute
2.33
0.677
1.31
2.04
3.81
3.82
3.91
3.93
3.87
3.87
4.27
4.1>
4.26
3.74
J.51
3.85
3.82
3.97
4.11
4.13
4.16
4.02
3.87
4.01
3.87
3.86
3.92
3.95
3.90
3.92
3.99
3.97
3.89
3.91
3.88
3.89
3.89
3.91
1 02
6.20
9.38
5.70
5.10
5.52
6.54
8.41
9. -12
4.79
4.81
7.31
3. IJ
7.82
4.59
I.Hii
9.58
7.59
5 . 50
10.68
8.59
12.58
7.10
4.68
8.34
5.81
5.48
8.34
9.03
8. 16
9.23
10.41
9.52
4.92
7.24
5.82
6.31
7.12
7.68
T. Ma
1,-H'l
22.66
11.69
5 CO
SB. 33
88.02
85.96
85.52
86.81
86.85
78.00
HI. IB
78.92
89.85
.ID. 1 1
87.35
88.05
R5 16
82. 20
81.8-1
81.36
.01.1 I
89.73
86. 02
89.73
89.99
88. 4 S
87.80
88.91
88.5
86.96
87. -IS
89.30
88.81
M>.51
89.13
89.23
88.71
'v CO
O.KO
0.50
0.80
0.80
2.2J
2.11
1.84
1.77
4.29
4.11
8 PI
8.80
7.98
1.19
O -JO
0.50
0.60
0.90
O.GU
0.70
0.40
O. in
1.12
1.0-1
0.98
0.91
0 . 55
0.52
0.58
0.44
0.26
0.2S
1.02
0.78
0.!) 1
0.81
0.84
0.71
"c CO 2
m.'.'u
C6.49
81.04
87 21
2.51
2.02
0.82
0.7-1
2.93
2.91
.1 IP
5.1J
3.53
2.68
L* ._'tl
0.90
1.20
2.80
1.70
2.20
0.70
1 70
3.31
J.23
2.50
2.46
1.38
1.05
1.12
0.66
0.31
0.30
3.45
2.21
2.77
2.84
2.16
2.13
I CZH4
O.'JO
0.80
0.60
O.7O
1.22
1.15
2.81
2.J8
1.01
1.15
1 "fi
l.J'J
1.59
1.49
l.:>0
1.50
2.40
1.10
1. JO
1.90
1.20
2 :ir>
0.88
0.43
0.68
0.93
1.03
1.36
0.71
1.00
1.89
2.21
1.14
0.80
0.80
0.75
0.19
0.29
t CH4
3. no
2.99
4.30
3.29
I.OP
b - Refers to gms Cl2/period in decanter water.
c - Refers to gms Clj/perlod in quench water.
-------
Appendix
Tablo 1;
Oncr-Ttirough Oin.-rJt.inq mid Calculated Data
(Continued)
Run #, Period
1. 1
2
3
2. 1
2
3
3. 1
2
3
4
4. 1
2
3
4
5, 1
2
3
4
6, 1
2
3
4
7. 1
2
3
4
8. 1
2
3
4
9. 1
2
3
4
10. 1
2
3
4
11, 1
2
12. 1
2
13. 1
2
3
4
% CjH,
% EDC
0.17
% Cl,
C2H«
Conversion
91.1
89.6
88.5
96.2
92.3
93.2
96.8
95.2
95.7
93.5
98.6
98.3
95.3
95.2
98.3
97.6
93.5
0-i.S
98.3
98.6
94.8
95.5
99.2
98.2
9-1.6
91.0
9C.O
98.1
01.9
96.5
98.6
97.9
93.5
93.2
95.6
06. 3
93.0
92.5
97.1
97.5
96.9
94.9
94.6
95.2
93.5
92.1
C2H4
Yield
82.7
86.6
88.0
83.6
87.1
85.7
88.6
86.9
88.2
91.3
92.6
94.0
96.6
95.2
93.3
92.1
97.3
05.7
91.7
93.3
94.7
91.2
93.6
93.5
On.l
100.1
94.8
91.4
qq.o
91.1
92.1
96.2
96.3
94.7
94.5
95.1
97.5
97.1
91.0
86.5
91.3
99.0
95.1
95.8
97.5
98.8
C2H«
Efficiency
75.3
77.6
77.9
80.5
80.4
79.8
85.7
82.7
84.4
85.4
91.3
92.4
92.0
90.6
91.7
89.9
91.0
01 .5
90.3
02.0
89.8
87.1
92.9
91.8
88. 1
91.0
01.1
89.7
11 .0
87.9
90.8
94.2
yu.o
88. 2
90.3
91 .5
90.6
89.8
88.4
84.3
88.4
93.9
90.0
91.2
91.1
91.0
HC1
Conversion
100.0
100.0
i
99.9
99.8
100.0
100.0
100.0
100.0
99.9
99.9
99.9
99.9
99.8
99.9
OU.9
99.9
100.0
100.0
oo. o
99.9
99.9
99.7
. 7
57.6
59.6
G1.7
5U.O
57.8
59.1
GO.O
59.4
58.9
58.0
55.3
58.0
61.6
59.0
59.8
59.8
59.7
Crude
CDC
Purity
wt. 1
98.87
98.96
99.17
98.33
98.36
98.25
98.40
S8.29
98.95
99.00
98.50
98.50
99.28
99.34
96. -42
98.18
99.09
on . o.s
98.34
98.55
99.09
99.09
98.40
98.52
00. OP
99.19
JS.u-l
98.57
on . p~
99.34
98.85
98.07
9U.15
!><1.22
98.72
08.80
99.20
99.09
98.01
98.75
98.84
98.97
98.28
98.23
98.93
98.97
Total
HC + EDC
Emissions
Ko'K.l "Cl
0.0496
0.0564
O.OP16
O.OJ45
0.0423
0.0382
0.0218
0.0282
0.02GG
0.0355
O.P13I
0.0148
0.0273
0.0275
0.0148
0.0175
O.OJ4J
0 pr.vi
0.0148
0.01JG
O.C201
0.0.264
0.0112
0.0153
0 0101
0.0450
O.iLMa
0.0158
O.PIIr«
0.0224
O.OlJd
0.01GP
O.OJ44
0.0.i:>7
0.0264
O.OJJI
0.0369
0.0390
0.02.i2
0.0227
0.0207
0.0290
0.0297
0.0274
0.0347
O.O403
Ul
-------
Appendix
Table l!
Once-Through Operating and calculated Data
(Continued)
Run *, Period
14. 1
2
3
4
IS. i
2
3
4
16. 1
2
3
4
5
17. 1
2
3
4
18, 1
2
3
4
5
22. 1
2
23. 1
2
3
4
24. 1
2
3
4
25. 1
2
3
26. 1
2
3
% C2H6
0.30
0.30
0.30
0.30
0.20
% EDC
0.17
% Cla
0.11
0.17
0.14
0.07
0.06
0.07
0.004
0.0
0.0
0.0
0.0
0.0
0.30
0.32
CjlU
Conversion
97.4
98.6
98.3
96.9
95. 8
96.0
90.1
91.6
96.4
96.0
92.4
95. 1
93.8
95.3
95.0
94.8
91.7
95.9
95.0
02.7
95.4
91.4
97.0
98.5
97.6
96.7
96.3
95.1
97.4
96.4
93.1
91.9
95.9
97.1
97.2
97.3
99.2
98.9
CjH,
Yield
91.6
88.3
88.6
90.1
95.0
95.3
99.3
98.2
92.9
93.8
94.2
91.9
93.5
93.0
93.6
95.3
98.3
91.2
89.2
00.0
91.5
97.3
88.8
86.3
93.7
95.1
95.0
96.2
96.5
96.6
99.5
99.0
90.7
92.2
91.8
89.2
90.5
89.7
C2I1<
Efficiency
89.2
87.0
87.0
87.3
91.0
91.5
89.5
89.9
89.6
90.0
87.1
87.4
87.8
88.6
88.9
90.3
90.2
87.5
84.8
83.5
87.2
88.9
86.2
84.9
91.4
91.9
91.5
91.5
94.0
93.2
92.6
91.0
87.0
89.5
89.2
86.8
89.8
88.7
IIC1
Conversion
99.9
99.9
99.9
100.0
90.9
99.9
99.9
99.9
99.9
99.9
90.9
99.9
99.9
100.0
99.9
99.9
90.9
99.9
99.9
99.9
99.9
99.9
19.5
99.4
99.7
99.7
99.7
99.7
99.8
99.7
98.9
98.7
95.9°
93.1
89.8
94.9
95.7
94.8
99.7
100.0
99.9
99.9
100.0
99. 9 | 100.0
99.9
100.0
99.9
99.6
99.6
77.2
75.2
IIC1
Yield
96.0
93.7
93.7
94.0
95.7
96.3
94.2
94. G
94.2
94.7
91.6
91.9
92.3
9 J.I
93.4
95.0
O'l.O
95.5
92.5
91.1
95.2
97.0
89.2
88.1
94.7
95.0
94.5
94.6
96.8
96.0
96.2
94.7
9<
92.1
68.8
94.7
72.8
73.8
104.7
H'J.8
74.6
110.0
flO.l
141.9
84.2
71.3
89.9
77.1
76.0
91.5
96.9
94.6
99.6
110.6
100.4
69.9
82.9
75.4
75.7
82.3
64.6
Efficiency
51.1
49.9
49.9
50.0
59.7
60.0
58.7
59.0
58.7
59.0
57.1
57.3
57.5
58.1
58.3
59.2
5'J.l
55.2
53.4
B2.G
55.0
56.0
56.6
55.7
57.4
57.7
57.4
57.5
59.0
58.5
58.2
57.1
54.6
56.2
56.0
54.5
56.4
55.7
Crude
EDC
Purity
Kt. <;
90.40
98.43
98.06
98.06
98.71
98.56
99.13
99. 13
98.75
98.69
98.57
98.54
98.74
90.51
93.53
98.58
Ub.ou
98.02
98.11
"8. SI
98.98
U8.b5
98.05
97.90
98.23
98.11
9H.7H
98.82
9B.5J
98.79
98.82
98.67
98.30
98.34
08. 2J
98.36
98.26
98.27
Total
IIC t EDC
Emissions
kg /kg HC1
0.0120
0.00367
0.00609
0.0133
o.n_';i-'
0.0243
0.0485
0.0126
O.P227
0.0246
O.i'.iUS
O.P2S4
0.0339
O.DJ7J
0.02S4
0.0294
O.iMlii
O.OG65
0.0629
O.iiS.-.O
0.0648
0. 08-16
0.0216
0.0155
0.01S6
0.0222
O.ii-' 11
0.0212
0.0197
0.0237
0.0283
0.0425
0.0255
0.0206
0.0-' 03
0.0198
0.0116
0.0131
d - Clj Conversion, %.
e - Cla Yield. %.
f - Cla Efficiency. %.
-------
Appendix
Table 2: Recycle Operating Data
Run #
( 100)101C
101D
105
106
107
108
109
110
Period
1
2
1
2
3
4
1
1
2
1
2
3
4
1
2
3
4
1
2
3
4
1
2
3
4
Ave. Mol.
Wt. vent
33.63
32.23
35.40
40.32
41.92
42.72
40.62
40.01
41.27
40.94
40.13
41.43
41.51
41.65
42.23
42.46
41.94
41.61
41.34
41.07
41.39
39.16
41.08
41.17
42.63
T Recycle'
wfSfc
26
26.5
30.5
35
39.5
38.5
34.0
34.0
33.5
31.5
31.8
32
32
40
40.5
34
33.5
32
32
32.2
32.5
33.5
33.6
32.5
32.5
Recycle
Pressure
psig
63
63
65
66
66
65
65
67
68
68
68
68
68
68
68
68
69
69
68
68.5
G8
68.5
67.5
67.5
68
Uncorrccted
Recycle Rate
g/min
103
106
114
125
132
134
112
128
129
129
129
131
131
130
131
132
132
128
128
127
128
127
127
127
128
Vent
Pressure
psig
67.5
68.0
68
69
69
68
67
71
71.5
71
71
71
71
71
71
71
71.5
72
71.5
71.5
71.5
71.5
70.5
71
71
Uncorrected
vent Rate
g/min
1.0
1.0
3.5
2.0
5.3
6.0
6.7
3.0
7.0
5.7
6.2
9.0
3.7
5.4
7.0
6.0
5.4
5.2
7.0
5.8
4.0
3.5
3.0
4.0
1.5
Sample
Temp.
°C
24
24
22.5
23
23
23
24.5
25
25
22.5
23.0
23.5
24
25
25
23
22.5
24
24.5
24.3
24
25
23.5
23.5
23.5
Sample
Pressure
psig
5
5
6.0
6.2
5.8
5.8
5.0
5.0
6.3
5.5
5.5
5.5
5.5
6.0
5.5
5.75
5.75
5.3
5.3
5.5
5.3
6.0
6.0
6.0
6.0
Uncorrected
Sample Vent
Rate, g/iiin
1.5
1.5
1.65
1.83
1.81
1.73
1.55
1.65
1.60
1.48
1.47
1.51
1.51
1.47
1.58
1.59
1.59
1.63
1.63
1.63
1.65
1.65
1.67
1.72
1.76
-------
Appendix
Table 2; Recycle Operating Data
(Continued)
-J
00
Run #
111
112
113
114
115
116
117
118
Period
1
2
3
1
2
3
1
2
3
4
1
2
3
4
1
1
2
3
4
1
2
3
4
1
Ave. Mol.
Wt. Vent
41.34
41.86
42.14
40.36
40.26
41.01
39.48
40.37
41.07
41.90
37.14
39.27
49.73
39.95
41.10
39.83
40.81
41.70
41.94
28.55
28.62
28.53
28.51
40.85
T Recycle'
Vent
°C
31.5
31
31
30.2
31
31
34
34
33.7
34
33.5
33.5
33
33.5
31.5
32.5
32.7
32.5
32.5
26.8
27.2
29
27
33
Recycle
Pressure
psiq
67.5
67.5
67
65
65.5
65
67
67
67
66.5
66
65.5
65.5
64
64
66
66
66.5
65.5
-
-
-
-
63
Uncorrccted
Recycle Rate
g/min
129
129
131
123
123
124
134
132
133
135
123
123
125
120
122
132
133
136
135
-
-
-
-
124
Vent
Pressure
psiq
71.5
71
71
72
72
72
75
75.5
75.5
75
75
75
76.5
76
79.5
77.5
77.5
78
75.5
13
13
13
13
71
Uncorrected
Vent Rate
g/min
8.7
6.7
4.0
9.0
6.8
7.5
3.7
3.2
2.5
0.5
1.5
2.2
1.5
3.5
2.6
2.5
2.5
2.5
2.5
-
-
-
-
2.0
Sample
Temp.
°C
23
22.5
22
22
22
22
24.5
25
24.4
24
24.5
25
24
23.5
21
24
23.7
23.5
23.5
27
25
26
24.5
23
Sample
Pressure
psiq
6.5
6.5
5.9
5.5
5.75
5.5
5.0
5.0
5.2
5.0
6.5
6.5
6.75
6.75
6.2
6.3
6.6
6.8
6.8
6.2
6.3
6.2
6.2
6.0
Uncorrected
Sample Vent
Rate, q/min
1.65
1.72
1.73
1.52
1.53
1.53
1.63
1.G8
1.73
1.73
1.50
1.55
1.62
1.60
1.68
1.71
1.77
1.87
1.92
1.22
1.22
1.22
1.24
1.55
-------
Appendix
Table 2;
Recycle Operating Data
(Continued)
(O
Run #
(100H01C
(101)1010
105
106
107
108
109
110
Period
1
2
1
2
3
4
1
1
2
1
2
3
4
1
2
3
4
1
2
3
4
1
2
3
4
HC1 Feed
9/min
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
73.7
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
HC1 Feed
Gmoles/min
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.O73
2.073
2.073
2.073
2.073
2.021
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
C2H< Feed
g/min
29.3
29.3
30.2
30.8
30.8
30.8
31.2
31.2
31.2
32.5
32.5
32.5
32.5
31.2
31.2
31.2
31.2
31.2
31.2
31.2
31.2
31.8
31.8
31.8
31.8
C2H4 Feed
Gmolcs/min
1.043
1.043
1.075
1.097
1.097
1.007
1.111
1.111
1.111
1.157
1.157
1.157
1.157
l.lll
1.111
1.111
1.111
1.111
1.111
1.111
1.111
1.132
1.132
1.132
1.132
O2 Feed
g/min
20.4
20.8
21.4
23.4
23.4
23.4
25.3
24.3
24.3
26.8
27.3
27.3
27.3
24.3
25.3
25.3
25.3
25.3
26.3
26.1
25.8
27.3
27.3
27.3
27.3
O2 Feed
Cmoles/min
0.638
0.650
0.669
0.731
0.731
0.731
0.791
0.759
0.759
0.838
O.B53
0.853
0.853
0.759
0.791
0.791
0.791
0.791
0.822
0.816
0.806
0.853
0.853
0.853
0.853
N2/CO2
Pressure
psiq
100
100
100
103
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
88
50
25
25
33
33
N2/CO2 Flow
g/min
2.81 (N2)
2.81 (N2)
3.76 (C02)
3.76 (C02)
3.76 (C02)
3.76 (C02)
3.76 (C02)
3.76 (CO,)
3.76 (CO2)
3.76 (CO2)
3.76 (C02)
3.76 (C02)
3.76 (C02)
3.76 (C02)
3.76 (C02)
3.76 (C02)
3.76 (C02)
3.76 (C02)
3.76 (C02)
3.56 (COj)
1.70 (C02)
0.177 (C02)
0.133 (C02)
0.485 (C02)
0.146 (C02)
-------
Appendix
Table 2:
Recycle Operating Data
(Continued)
00
O
Run #
111
112
113
114
115
116
117
118
Period
1
2
3
1
2
3
1
2
3
4
1
2
3
4
1
1
2
3
4
1
2
3
4
1
HC1 Feed
g/min
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
75.6
HC1 Feed
Gmoles/min
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
2.073
C2H« Feed
g/min
32.3
32.3
32.3
32.3
33.0
33.0
30.3
30.3
30.3
30.3
30.8
30.8
30.3
30.3
30.8
30.8
31.0
31.0
31.0
30.6
30.6
30.6
30.6
28.3
C21I« Feed
Gmoles/min
1.150
1.150
1.150
1.150
1.175
1.175
1.079
1.079
1.079
1.079
1.097
1.097
1.079
1.079
1.097
1.097
1.104
1.104
1.104
1.090
1.090
1.090
1.090
1.008
O2 Feed
g/min
29.2
28.3
28.3
28.3
28.3
28.3
22. 8
22.8
22.4
22.0
21.4
22.8
22.8
22.0
24.0
23.75
23.0
23.0
23.0
121.6(Air)
121.6(Air)
121.6(Air)
121.6(Air)
20.0
O2 Feed
Gmoles/min
0.913
0.884
0.884
0.884
0.884
0.884
0.713
0.713
0.700
0.688
0.669
0.713
0.713
0.688
0.750
0.742
0.719
0.719
0.719
4.193(Air)
4.193(Air)
4.193(Air)
4.193(Air)
0.625
N2/C02
Pressure
psiq
42
41
39
50
50
50
50
50
50
50
50
50
50
50
50
60
60
60
60
63.5
63.5
63.5
63.5
50
N2/C02 Flow
g/min
0.529 (C02)
0.525 (COj>)
0.515 (C02)
0.509 (C02)
0.396 (CO2)
0.396 (C02)
0.565 (C02)
0.565 (C02)
0.565 (C02)
0.565 (C02)
0.565 (C02)
0.565 (C02)
0.565 (C02)
0.565 (C02)
0.565 (C02)
0.425 (C02)
0.425 (C03)
0.425 (C02)
0.425 (C02)
4.454 (N2)
4.454 (N2)
4.454 (N2)
4.454 (Na)
0.723 (C0a)
-------
Appendix
Table 2; Recycle Operating Data
(continued)
Run #
(100)101C
( 101)1010
105
106
107
108
109
110
Period
1
2
1
2
3
4
1
1
2
1
2
3
4
1
2
3
4
1
2
3
4
1
2
3
4
N2 / COj Flow
Gmoles/min
0.10 (N2)
0.10 (N2)
0.0855(C02)
0.0855(C02)
0.08S5(C02)
0.0855(C02)
0.0855(C02)
0.0855(C02)
0.0855(C02)
0.0855(C02)
0.0855(C02)
0.0855(C02)
0.0855(C02)
0.0855(CO2)
0.0855(C02)
0.08S5(C02)
0.0855(CO2)
0.0855(CO2)
0.0855(C02)
0.0808(C02)
0.0385(C02)
0.00402(CO2)
0.00302(CO2)
0.0110(CO2)
0.00331(CO2)
Reactor
P
46
47
45. 5
46
46
46
46
46
46
45
45
45
45
45
45.5
45
46
45
45
45
45
45
45
45
45
T
246
244
250
249
244
242
2-12
241
2-12
244
244
241
244
244
244
241
239
243
241
240
241
251
251
251
249
Quench
qms/min
32.5
30.0
30
30
30
30
30
30
30
30
30
30
30
30
30
30
30
23
23
34.8
30
30
32.5
30
30
Crude
Product
q ma /period
6071
4566
6214
5936
6413
6373
6301
6302
6244
6484
6357
6325
6312
6380
6365
6305
6401
6272
6330
6270
6296
6211
6359
6349
6655
Decanter
water
qms/perxod
1060
720
1365
1105
1210
1235
1250
1229
1229
1578
1282
1301
1301
1220
1210
1200
1190
1241
1281
1221
1221
1310
1320
1340
1310
Quench
Bottoms
gins/period
1947
1560
1857
1715
1866
1884
1630
1782
1663
1914
1962
1884
1683
1922
1892
1842
1962
1643
1583
1894
1824
1486
1729
1650
1759
HC1 in
Decanter H2O
qras/period
0.300
0.140
0.443
0.517
0.427
0.355
1.30
0.355
0.311
0.373
0.350
0.332
0.308
0.222
0.24
0.26
0.30
0.27
0.28
0.27
0.22
0.43
0.48
0.49
0.43
HC1 in
Quench
gins/period
14.9
16.06
34.76
17.52
16.69
13.50
8.09
5.45
2.72
2.089
1.64
1.85
2.57
1.68
2.21
1.87
2.00
2.51
2.65
2.98
2.72
8.63
14.43
22.73
13.72
Period
mm
60
45
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
Date
3/4/75
II
3/7/75
H
it
3/13/75
3/14/75
11
3/18/75
11
11
11
3/19/75
11
"
it
3/20/75
11
11
"
3/21/75
11
n
00
-------
Appendix
Table 2:
Recycle Operating Data
(Continued)
Run #
111
112
113
114
115
116
117
118
Period
1
2
3
1
2
3
1
2
3
4
1
2
3
4
1
1
2
3
4
1
2
3
4
1
N3 /C02 Flow
Gmoles/min
0.0120(C02)
0.0119(C02)
0.0117(C02)
0.0116CCO, )
0. 00899 (C02)
0.008D9(C02)
0.0128(CO, )
0.0128(C02)
0.0128(C02)
0.0128(C02)
0.0128(C02)
0.0128(C02)
0.0128(COa)
0.0128(C02)
0.0128(C02)
0.00966(C02)
0.00966 (COa)
0. 00966 (C02)
0.00966(C02)
0.159(N2)
0.159(N2)
0.1S9(N2)
0.159(N2)
0.0164 (C02)
Reactor
P
45
45
45
45
45
45
45
45
45
45
45
45
45
44
45
45
45
45
45
45
45.5
45
45
44
T
254
252
251
252
252
251
231
231
230
230
231
231.7
230
231
238
232
231
230
229
239
242
232
230
223
Quench
qms/min
30
30
30
30
30
30
30
30
30
30
30
30
30
30
30
30
28.8
30
30
30
30
30
30
30
Crude
Product
qms/period
G286
6453
6309
6312
6417
6455
6226
6175
6255
6304
6303
6201
6242
6349
6378
6273
6306
6417
6448
6014
6002
5955
6012
1543
Decanter
Water
qms/period
1282
1267
1252
1509
1319
1301
1124
1173
1142
942
1163
1147
1106
1165
1165
1101
1320
1150
1150
1170
1150
1140
1150
301
Quench
Bottoms
qms/period
1851
1645
1779
1544
1648
1818
1555
974
1242
1804
1363
1764
1623
1633
1473
1914
1952
1734
1633
1873
2072
1673
1613
521
I1C1 in
Decanter H2O
qms/period
0.33
0.23
0.23
0.38
0.29
0.38
0.24
0.21
0.25
0.21
0.21
0.21
0.24
0.21
0.59
0.20
0.29
0.29
0.25
0.13
0.13
0.12
0.15
0.055
HC1 in
Quench
qms/period
1.74
2.44
2.45
7.36
14.98
12.67
0.73
0.71
0.68
1.38
2.83
2.31
1.83
2.79
6.07
0.56
0.92
0.89
1.07
3.40
5.13
4.90
4.60
0.27
Period
mm
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
60
15
Date
3/31/75
11
ii
4/1/75
II
11
4/2/75
II
11
11
4/3/75
II
11
11
4/8/75
4/9/75
"
11
11
4/10/75
11
I
n
4/11/75
00
to
-------
Appendix
Table 3; Calculated Recycle Data
00
to
Run #, Period
100. 1
2
101. 1
2
3
4
105, 1
106, 1
2
107, 1
2
3
4
108. 1
2
3
4
109, 1
2
3
4
110, 1
2
3
4
Rx T °C
246
244
250
249
244
242
242
241
242
244
244
241
244
244
244
241
239
243
241
240
241
251
251
251
249
Rx P
psig
46
47
45.5
46
46
46
46
46
46
45
45
45
45
45
45.5
45
46
45
45
45
45
45
45
45
45
% xs
C2H4
14.6
21.5
4.9
6.7
7.0
B.3
9.2
10.0
10.5
16.5
20.4
21.6
30.8
10.8
11.3
12.1
11.3
9.7
9.7
13.2
11.0
13.5
11.2
10.4
10.7
% XS
02
57.2
75.5
83.0
61.4
60.5
52.5
68.0
77.5
60.8
74.9
86.0
75.3
75.3
55.9
60.8
62.0
94.6
71.5
101.5
115.2
113.2
71.6
70.7
74.3
68.4
Gmoles/hr
HC1
124.38
11
"
II
»
If
11
II
11
II
II
II
121.25
124.38
II
11
II
II
"
11
II
II
"
n
"
Avc. Hoi.
Weight
vent &
Recycle
33.91
33.16
35.92
40.41
42.08
42.82
40.67
40.08
41.43
41.02
40.21
41.50
41.57
41.72
42.33
42.58
42.02
41.68
41.40
41.17
41.49
39.42
41.24
41.40
42.92
Superficial
Velocity
H/S
0.337
0.338
0.353
0.350
0.348
0.345
0.333
0.353
0.351
0.366
0.370
0.365
0.364
0.35G
0.354
0.356
0.350
0.358
0.358
0.359
0.357
0.374
0.367
0.366
0.361
Ft/S
1.106
1.111
1.158
1.149
1.141
1.133
1.093
1.157
1.151
1.201
1.214
1.199
1.136
1.1G9
1.161
1.169
1.140
1.174
1.175
1.178
1.171
1.228
1.202
1.201
1.185
Recycle Rate
KG/Hr
5.043
5.556
6.012
6.585
6.903
6.975
5.873
6.795
6.896
6.918
6.915
7.020
7.020
6.877
6.924
7.050
6.991
6.900
6.859
6.824
6.853
6.809
6.767
6.779
6.853
KGmoles/
hour
0.1593
0.1675
0.1674
0.1630
0.1641
0.1629
0.1444
0.1696
0.1G64
0.1686
0.1720
0.1692
0.1689
0.1648
0.1636
0.1656
0.1664
0.1655
0.1657
0.1658
0.1052
0.1727
0.1641
0.1638
0.1597
Total vent
Rate
KG/Hr
0.266
0.266
0.412
0.343
0.515
0.546
0.570
0.384
0.603
0.523
0.549
0.704
0.688
0.503
0.594
0.545
0.514
0.506
0.603
0.538
0.440
0.414
0.387
0.446
0.312
KUmoles/
hour
0.0078
0.0080
0.0115
0.0085
0.0122
0.0128
0.0140
0.0096
0.0146
0.0127
0.0137
0.0170
0.0166
0.0120
0.0140
0.0128
0.0122
0.0121
0.0146
0.0131
0.0106
0.0105
0.0094
0.0108
0.0073
-------
Appendix
Table 3: Calculated Recycle Data
(Continued)
09
Run #, Period
111. 1
2
3
112, 1
2
3
113. 1
2
3
4
114, 1
2
3
4
115. 1
116, 1
2
3
4
117, 1
2
3
4
118, 1
Rx T °C
254
252
251
252
252
251
231
231
230
230
231
231.7
230
231
238
232
231
230
229
239
245
232
230
223
Rx P
paig
45
45
45
45
45
45
45
45
45
45
45
45
45
44
45
45
45
45
45
45
45.5
45
45
44
% xs
C2H4
12.4
12.2
12.2
17.5
20.0
18.6
14.6
13.6
]3.0
12.1
12.6
12.4
10.9
9.2
8.4
14.0
16.7
18.8
17.8
5.3
5.3
5.3
5.3
4.6
% xs
02
100.3
105.3
110.7
76.5
78.1
78.0
73.8
71.1
70.2
55.0
62.0
63.1
60.6
71.4
82.6
77.7
55.6
49.2
53.1
70.1
70.1
70.1
70.1
77.9
Gmoles/hr
IC1
124.38
N
11
"
(I
11
11
M
II
M
"
II
M
II
II
(I
H
If
II
"
n
11
11
Avc. Mol.
weight
Vent &
Recycle
41.46
41.90
42.23
40.55
40.30
41.04
39.66
40.69
41.29
42.11
37.35
38.80
40.93
40.27
41.33
40.14
41.14
41.92
42.46
28.75
28.75
28.66
28.61
40.99
Superficial
Velocity
M/S
0.375
0.370
0.370
0.366
0.369
0.366
0.356
0.350
0.347
0.345
0.350
0.346
0.339
0.339
0.342
0.354
0.350
0.350
0.346
0.308
0.399
0.392
0.391
0.328
Ft/S
1.230
1.215
1.215
1.201
1.210
1.201
1.167
1.147
1.139
1.133
1.147
1.136
1.112
1.112
1.121
1.162
1.148
1.150
1.135
1.305
1.310
1.287
1.282
1.076
Recycle Bate
KG/hr
6.897
6.903
6.989
6.490
6.501
6.534
7.114
7.008
7.064
7.145
6.495
6.475
6.586
6.258
6.383
6.982
7.032
7.215
7.118
0
0
0
0
6.430
KGmoles/
hour
0.1664
0.1648
0.1655
0.1600
0.1613
0.1592
0.1794
0.1722
0.1711
0.1697
0.1739
0.1669
0.1609
0.1554
0.1544
0.1739
0.1709
0.1721
0.1676
0
0
0
0
0.1569
Total Vent
Rate
KC/hr
0.701
0.595
0.447
0.710
0.589
0.627
0.425
0.401
0.366
0.254
0.299
0.341
0.308
0.418
0.375
0.369
0.374
0.381
0.382
6.668
6.744
6.761
6.759
0.206
KGmoles/
hour
0.0169
0.0142
0.0106
0.0175
0.0146
0.0153
0.0107
0.0099
0.0089
0.0060
0.0080
0.0088
0.0075
0.0104
0.0091
0.0092
0.0091
0.0091
0.0090
0.2319
0.2346
0.2359
0.2363
0.0050
-------
Appendix
Table 3:
calculated Recycle Data
(Continued)
00
Ui
Run #, Period
100, 1
2
101. 1
2
3
4
105, 1
106, 1
2
107, 1
2
3
4
108, 1
2
3
4
109, 1
2
3
4
110, 1
2
3
4
Total Feeds
Incl. Recycle
KG/hr
12.91
13.09
13.63
14.36
14.68
14.75
13.79
14. 65
14.75
15.00
15.03
15.13
15.02
14.73
14 . B.I
14.96
14.91
14.81
14.83
14.84
14.80
14.88
14.84
14.85
14.92
KG moles/
hour
0.3843
0.3933
0.3962
0.3967
0.397B
0.3967
0.3826
0.4059
0.4028
0.4124
0.4166
0.4138
0.4104
0.4011
0.4017
0.4038
0.4046
0.4037
0.4057
0.4076
0.4043
0.4159
0.4073
0.4069
0.4029
Vol. 1
Recycled
95.31
95.44
93.59
95.05
93.05
92.74
91.15
94.65
91.96
92.97
92.64
90.88
91.07
93.19
92.10
92.82
93.15
93.17
91.92
92.69
93.96
94.27
94.58
93.83
95.64
Total IIC
+ CDC
Emissions
KG/K«J HCl
0.00341
0.00431
0.00236
0.00046
0.00112
0.00127
0.00102
0.00087
0.00204
0.00178
0.00292
0.00435
0.00658
0.00136
0.00193
0.00205
0.00156
0.00106
0.00121
0.00129
0.00139
0.00203
0.00103
0.00124
0.00107
HCl
Conv. 1
99.7
99.5
99.2
99.6
99.6
99.7
99.8
99.9
99.9
99.9
100.0
100.0
99.9
100.0
99.9
100.0
99.9
99.9
99.9
99.9
99.9
99.8
99.7
99.5
99.7
HCl
Yield 1
97.3
97.9
100.2
95.1
102.6
102.1
100.6
100.7
99.3
103.8
101.8
101.2
103.4
101.8
101.2
100.4
102.2
99.8
100.6
100.0
100.5
99.1
101.5
101.3
106.1
HCl
Efficiency
%
97.0
97.4
99.4
94.7
102.2
101.7
100.4
100.6
99.2
103.7
101.8
101.1
103.3
101.7
101.2
100.3
102.2
99.8
100.6
100.0
100.4
99.0
101.2
100.8
105.8
C,H4
Conv. %
98.7
98.4
98.9
99.6
99.0
98.8
99.4
99.1
98.8
98.9
99.1
98.3
97.7
98.8
98.7
98.7
98.8
98.9
98.8
98.8
98.9
99.2
99.1
99.1
99.1
C2»«
Yield 1
97.4
98.2
96.8
89.7
97.5
97.2
94.1
94.6
93.5
93.9
91.9
92.0
92.2
95.9
95.5
94.7
96.4
94.0
94.9
91.3
94.6
91.2
93.3
93.0
97.6
C2H«
Efficiency
%
96.2
96.7
95.7
89.4
96.5
96.0
93.5
93.7
92.4
92.8
91.0
90.4
90.1
94.8
94.3
93.5
95.2
93.0
93.7
90.3
93.5
90.5
92.5
92.1
96.7
-------
Appendix
Table 3:
Calculated Recycle Data
(Continued)
00
01
Run ft. Period
112. 1
2
3
113. 1
2
3
4
114, 1
2
3
4
115. 1
116, 1
2
3
4
117, 1
2
3
4
118, 1
Total Feeds
Incl. Recycle
KG/hr
14.65
14.70
14.73
14.82
14.72
14.75
14.81
14.15
14.22
14.30
13.92
14.20
14.78
14.80
14.98
14.88
13.94
13.94
13.94
13.94
13.86
KG moles/
hour
0.4061
0.4080
0.4068
0.4110
0.4038
0.4019
0.3998
0.4040
0.3995
0.3925
0.3855
0.3893
0.4084
0.4044
0.4056
0.4011
0.4524
0.4524
0.4524
0.4524
0.3790
Vol. %
Recycled
90.14
91.69
91.24
94.36
94.59
95.08
96.57
95.61
95.00
95.54
93.74
94.45
94.98
94.95
94.98
94.90
0
0
0
0
96.89
Total lie
+ EDC
Emissions
KG/Kg HC1
0.00-115
0.00264
0.00223
0.00316
0.00331
0.00255
0.00158
0.00181
0.00199
0.00181
0.002 :.6
0.00146
0.00276
0.00326
0.00326
0.00416
0.02126
0.01776
0.02993
0.02597
0.00125
HC1
Conv . %
99.8
99.7
99.7
100.0
100.0
100.0
100.0
99.9
99.9
100.0
99.9
99.9
100.0
100.0
100.0
100.0
99.9
99.9
99.9
99.9
100.0
HC1
Yield %
100.7
102.3
103.2
100.1
99.3
100.4
101.4
101.2
98.8
100.4
102.3
102.1
100.8
101.5
103.1
103.6
97.7
97.1
96.8
97.6
99.8
IIC1
Efficiency
1
100.6
102.0
102.9
100.0
99.3
100.4
101.4
101.2
99.7
100.4
102.3
101.9
100.8
101.5
103.1
103.6
97.6
97.0
96.7
97.5
99.8
C2H<
Conv . %
98.8
98.5
99.0
98.6
98.7
98.5
98.9
98.8
99.2
99.3
99.3
99.1
98.7
98.7
98.5
98.4
98.2
97.8
94.9
95.3
99.8
C2H4
Yield %
91.7
91.2
91.6
97.4
96.5
97.8
98.4
96.7
94.8
97.0
98.8
97.0
96.3
96.4
98.1
98.7
94.5
94.2
96.7
97.2
102.8
CjH,
Efficiency
%
90.5
89.8
90.7
96.0
95.3
96.4
97.3
95.5
94.1
96.3
98.1
96.2
95.1
95.1
96.7
97.2
92.7
92.2
91.8
92.6
102.5
-------
Appendix
Table 3;
Calculated Recycle Data
(Continued)
00
Run #, Period
100, 1
2
101, 1
2
3
4
105, 1
106, 1
2
107, 1
2
3
4
108, 1
2
3
4
109, 1
2
3
4
110, 1
2
3
4
0,
Conv. %
98. 6
98.0
97.1
99.2
98.9
99.3
98.9
98.8
99.1
99.3
98.9
99.3
99.5
99.5
99.5
99.5
97.9
99.0
97.5
97.0
97.6
99.7
99.7
99.6
99.9
02
Yield %
80.6
79.9
80.0
68.2
73.8
73.2
67.0
70.1
68.9
65.2
63.0
62.4
62.0
70.4
67.2
66.6
69.0
66.6
65.6
66.0
6G.7
60.8
62.1
62.0
64.9
0Z
Efficiency
1
79.5
78.3
77.7
67.6
73.0
72.7
66.3
69.2
68.2
64.7
62.3
61.9
61.7
70.0
66.9
66.3
67.5
65.9
63.9
64.0
65.1
60.6
61.9
61.7
64.8
Vent
02 %
6.87
9.48
10.22
4.09
3.89
2.40
3.60
5.89
2.89
2.70
4.10
2.20
1.40
2.00
1.80
2.00
8.00
3.79
B.29
11.08
11.08
1.49
1.40
2.09
0.99
Vent
H2 (
45.80
46.68
40.96
15.68
5.88
1.80
14.29
16.88
10.77
9.79
12.69
4.99
1.20
7.49
3.09
1.70
2.60
8.49
6.79
6.99
4.09
17.62
9.47
7.67
2.49
Vent
CO %
8.16
7.08
4.26
3.89
3.69
3.49
3.30
2.50
2.89
5.49
5.10
5.89
7.59
4.29
4.99
4.59
2.70
2.70
2.60
2.00
2.50
9.86
6.98
7.97
4.78
Vent
C02 %
33.25
28.73
43.20
75.84
85.76
91.18
77.88
73.52
81.91
80.11
74.89
83.15
83.86
84.70
88.34
89.66
84.93
83.93
HI. 22
78.77
80.70
69.04
81.11
81.42
90.68
Vent
Call, %
5.38
7.68
0.40
0.30
0.40
0.90
0.80
1.00
1.20
1.75
3.10
3.59
5.79
1.30
1.50
1.80
1.50
0.90
0.90
0.90
1.40
1.49
0.70
0.40
0.50
Vent
CII4 %
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Vent
C2H9 'I
0.10
0.10
0.05
0.05
0.10
0.05
0.05
0.10
0.05
0.03
0.04
0.03
0.03
0.10
0.10
0.05
0.05
0.05
0.10
0.10
0.05
0.05
0.05
0.05
0.05
Vent
EDC ".
0.44
0.26
0.82
0.15
0.28
0.19
0.09
0.11
0.29
0.14
0.09
0.15
0.13
0.12
0.18
0.21
0.14
0.14
0.10
0.17
0.19
0.45
0.29
0.40
0.52
EDC
Purity
Wt. %
97.85
97.94
97.86
97.74
97.61
97.78
97.55
97.74
97.25
97.79
97.89
97.74
97.64
97.52
97.28
97.36
97.68
97.35
97.25
97.57
97.57
97.47
97.31
97.11
97.26
-------
Appendix
Table 3:
Calculated Recycle Data
(Continued)
00
00
Run #, Period
112, 1
2
3
113, 1
2
3
4
114. 1
2
3
4
115, 1
116, 1
2
3
4
117, 1
2
3
4
118. 1
oa
Conv. %
99.5
99.5
99.5
98.4
98.5
98.6
99.4
98.8
99.0
99.2
98.0
98.4
98.7
99.3
99.6
99.4
71.1
69.9
66.2
64.3
98.4
02
Yield %
59.7
60.5
61.1
74.6
73.9
76.0
77.5
80.0
73.9
74.2
79.3
72.1
71.9
74.3
75.2
75.8
80.7
81.6
85.9
89.1
84.7
oa
Efficiency
1*
i
59.4
60.2
60.8
73.4
72.8
74.9
77.0
79.0
73.1
73. G
77.7
71.0
70.9
73.7
74.9
75.3
57.4
57.0
56.8
57.3
83.4
Vent
02 t
1.40
1.70
1.70
6.48
6.27
6.57
4.28
6.08
4.98
4.68
7.96
7.87
6.37
3.28
2.09
2.87
6.58
6.79
7.59
7.99
11.56
Vent
N2 1
6.48
3.80
4.40
17.44
12.53
7.97
5.18
33.39
25.22
11.96
15.32
8.17
16.02
11.73
6.53
4.46
90.05
89.34
88.84
88.88
5.58
Vent
CO %
12.65
15.78
10.99
2.29
1.89
2.09
1.69
2.29
2.19
2.19
1.79
2.89
2.19
1.89
1.69
1.88
0.80
0.90
0.60
0.50
2.49
Vent
C02 %
76.53
76.03
80.74
69.83
75.28
79.69
85.50
55.42
64.78
78.13
72.31
79.52
71.92
78.75
84.79
85.61
1.79
2.20
1.40
1.20
77.06
vent
C^IU *
2.49
2.50
2.00
3.59
3.38
3.19
2.89
2.39
2.39
2.59
1.99
1.00
2.88
3.68
4.38
4.16
0.50
0.60
1.40
1.30
2.89
Vent
CII, %
0.05
0.05
0.05
0
0
0
0
0
0
0
0
0.05
0
0
0
0
0
0
0
0
0.05
Vent
C2H4 %
0.05
0.05
0.05
0.05
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0.10
0
0
0
0
0.10
Vent
EDC %
0.36
0.10
0.08
0.32
0.55
0.39
0.35
0.33
0.33
0.34
0.54
0.42
0.53
0.57
0.37
0.91
0.28
0.18
0.19
0.14
0.28
EDC
Purity
Wt. %
97.38
97. 20
97.53
98.31
98.43
98.35
98.47
98.32
98.42
98.49
98.51
97.83
98.31
98.45
98.32
98.27
98.90
-------
TECHNICAL REPORT DATA
(Please read In tinier ions on the rercnc faj
1 REPORT NO
EPA-600/2-76-053
3 RECIPIENT'S ACCESSION-NO
4. TITLE ANOSUBTITLE
Hydrocarbon Emissions Reduction from Ethylene
Bichloride Processes
5. REPORT DATE
March 1976
6. PERFORMING ORGANIZATION CODE
7 AUTHOH(S)W s AmatQj B. Bandy opadhyay, B.E.Kurtz,
and R. H. Fitch
8 PERFORMING ORGANIZATION REPORT NO
9 PERFORMING ORGANIZATION NAML" AND ADDRESS
Allied Chemical Corporation
Syracuse Technical Center (P.O. Box 6)
Solvay, New York 13209
10 PROGRAM ELEMENT NO
1AB015; ROAP 21AXM-020
11. CONT RACT/GRANT NO
68-02-1835
12 SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13 TYPE OF REPORT AND PERIOD COVERED
Initial Phase; 1/74-6/75
14 SPONSORING AGENCY CODE
EPA-ORD
is SUPPLEMENTARY NOrESEpA pr0ject officer K. Baker is no longer with EPA; for details
contact E.J.Wooldridge, Mail Drop 62, Ext 2547.
16 ABSTRACT
The report gives results of the initial phase of the development of a low-
emissions ethylene oxyhydrochlorination process for producing 1,2-dichloroethane
(ethylene dichloride). First, experimental work on an existing pilot-plant-scale,
once-through process was used both to obtain baseline emission data in mass of
hydrocarbon (HC) plus ethylene dichloride (EDC) per mass of HC1 fed as a function
of reactor temperature and percent excess ethylene to the reactor, and to resolve
potential problems which may arise in a recycle operation. Second, the existing
once-through pilot plant was converted to a recycle operation which then functioned
successfully and yielded emission data in mass of HC plus EDC per mass of HC1 fed
as a function of reactor temperature and percent excess ethylene to the reactor. In
particular, the project objective of reducing by 90% the HC plus EDC emissions from
an ethylene oxyhydrochlorination process, through the recycling of reactor off-gases,
was positively demonstrated. Third, various operating difficulties were assessed
which would be important for future control applications and scale-up efforts.
Economic analyses are presented to demonstrate the competitive position of the
improved process.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c COSATI i x-ld/Oroup
Air Pollution
Hydrocarbons
Chloroethanes
Hydrochloric Acid
Ethylene
Economic Analysis
Air Pollution Control
Stationary Sources
Ethylene Dichloride
Ethylene Oxyhydro-
chlorination
13B
07C
07B
05C
13 DISTRIBUTION STATEMENT
19 SECURITY CLASS (1 Ins Ki;;ui11
Unclassified
21 NO r>~
96
?o
Unclassmeu
tPA Form 2220 1 {9-73)
89
------- |