GCA-TR-75-32-GI10)
     ASSESSMENT OF ORTHO-XYLENE
AS A POTENTIAL AIR POLLUTION PROBLEM
                VOLUME X

              FINAL REPORT
           Contract No. 68-02-1337
             Task Order No. 8
                 Prepared For
       U.S. ENVIRONMENTAL PROTECTION AGENCY
              Research Triangle Park
              North Carolina 27711
                January 1976
GCA TECHNOLOGY DIVISION
           BEDFORD, MASSACHUSETTS 01730

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                                            CCA-TR-75-32-C(10)
     ASSESSMENT OF ORTIIO-XYLENE
AS A POTENTIAL AIR POLLUTION PROBLEM

             Volume X
                 by
        Robert M.  Patterson
         Mark I.  Bornstein
           Eric Garshick
          GCA CORPORATION
       GCA/TECHNOLOGY DIVISION
       Bedford,  Massachusetts ,
            January 1976
        Contract No.  68-02-1337
          Task Order No. 8
         EPA Project Officer
            Michael Jones


          EPA Task Officer
          Justice Manning
                                 PROPERTY  Or
                                 EPA LJD^ARY
                                     R7P,  tlC
 U.S.  ENVIRONMENTAL PROTECTION AGENCY
        Research Triangle Park
        North Carolina 27711

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This report was furnished to the U.S. Environmental Protection Agency by the
GCA Corporation, GCA/Technology Division, Bedford, Massachusetts 01730, in
fulfillment of Contract No. 68-02-1337, Task Order No. 8.  The opinions,
findings, and conclusions expressed are those of the authors and not neces-
sarily those of the U.S. Environmental Protection Agency or of the cooperating
agencies.  Mention of company or product names is not to be considered as an
endorsement by the U.S. Environmental Protection Agency.

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                                ABSTRACT
This report is one of a series which assesses the potential air pollution.
impacts of 14 industrial chemicals outside the work environment.  Topics
covered in each assessment include physical and chemical properties,
health and welfare effects, ambient concentrations and measurement meth-
ods, emission sources, and emission controls.  The chemicals investigated
in this report series are:                    '
                Volume I
                Volume II
                Volume III
                Volume IV
                Volume V
                Volume VI
                Volume VII
                Volume VIII
                Volume IX
                Volume X
                Volume XI
                Volume XII
                Volume XIII
                Volume XIV
Acetylene
Methyl Alcohol
Ethylene Bichloride
Benzene
Acetone
Acrylonitrile
Cyclohexanone
Formaldehyde
Methyl Methacrylate
Ortho-Xylene
Maleic Anhydride
Dimethyl Terephthalate
Adipic Acid
Phthalic Anhydride.
                                 iii

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                                CONTENTS




                                                                    Page




Abstract                                                            iii




List of Figures                                                     v




List of Tables                                                      v




Sections




I       Summary and Conclusions                                     1




II      Air Pollution Assessment Report                             3




            Physical and Chemical Properties                        3




            Health and Welfare Effects                              3




            Ambient Concentrations and Measurement                  6




            Sources of Ortho-Xylene Emissions                       9




            Ortho-Xylene Emission Control Methods                   13




III     References                                                  18




Append ix




A       Ortho-Xylene Manufacturers                                  20
                                  iv

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                                 FIGURE

No.                                                                 page

1    Estimated Installed Cost of Ortho-Xylene Storage Tanks
     (Equipment Costs Assumed to be the Same as Gasoline
     Storage Tanks)                                                 17


                                 TABLES

1    Significant Properties of Ortho-Xylene                         4

2    Estimated Isolated Ortho-Xylene Consumption   1974             10

3    Average Composition of Mixed Xylene                            11

4    Estimated Xylene Consumption - 1974                            11

5    Sources and Emission Estimates of Ortho-Xylene - 1974          12

6    Estimated Installed Costs of Adsorption Systems                15

7    Estimated Annual Operating Costs of Adsorption Systems         15

8    Estimated Installed Costs of Thermal and Catalytic
     Incinerators                                                   16

9    Estimated Annual Operating Costs of Thermal and Catalytic
     Incinerators                                                   16

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                                SECTION I
                         SUMMARY AND CONCLUSIONS

Xylene is a colorless, flammable liquid having an aromatic odor similar
to that of benzene and toluene.  There are three isomers of xylene:
ortho-, tneta-, and para-xylene.  Commercial xylene is a mixture of the
three forms with meta-xylene being the major component and ortho-xylene
making up about 20.5 percent of the mixture.  Ortho-xylene is produced
solely for the manufacture of phthalic anhydride, while mixed xylenes
are used as solvents, for the manufacture of xylene sulfonates and
xylidenes, and as high octane components of gasoline.

Data linking ortho-xylene exposure with health effects are lacking, due
to the almost always concomitant benzene and toluene.  Ortho-xylene is
an irritant and narcotic at high concentrations, producing effects sim-
ilar to alcohol intoxication.  The NIOSH recommended standard for xylene
is a time weighted average (TWA) exposure of 100 ppm for up to a 10-hour
workday, 40-hour workweek, with a ceiling concentration of 200 ppm for
10 minutes.

Simple diffusion modeling estimates place the likely maximum 1-hour
average ambient concentration at about 0.5 ppm of ortho-xylene.  The
maximum 24-hour average ambient concentration might be expected to be
about 0.3 ppm.

About 1 billion pounds of isolated ortho-xylene were produced at nine
locations in 1974, and production is expected to decline in 1975 before
slowly increasing (6 percent growth by 1978).  The primary emission

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sources in descending order are mixed xylene solvent usage, mixed xylene
production, ortho-xylene production and solvent usage, and bulk storage.
Total emissions are estimated to have been about 184 million pounds in 1974.

Although emission controls specifically for ortho-xylene are not reported,
two types of controls are used extensively by the chemical industry to
control hydrocarbon emissions.  These are vapor recovery and incineration.
Control by adsorption on activated charcoal is used when recovery is
economically desirable.  The primary advantage of incineration is that
low concentrations may be oxidized with only small supplemental fuel
requirements.  Fixed roof storage tanks can be controlled by venting to
an adsorber or to an incinerator, or they can be converted to floating
roof design.

Based on the results of the health effects research presented in this
report, and the ambient concentration estimates, it appears that ortho-
xylene as an air pollutant does not pose a threat to the health of the
general population.  In addition, ortho-xylene does not appear to pose
other environmental insults which would warrant further investigation or
restriction of its use at the present time.

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                               SECTION II
                     AIR POLLUTION ASSESSMENT REPORT

PHYSICAL AND CHEMICAL PROPERTIES

Xylene  is a clear, colorless, flammable liquid having an aromatic odor
similar to that of benzene and toluene.  There are three isomers of
xylene, ortho  (1, 2 dimethyl benzene), meta  (1, 3 dimethyl benzene),
and para (1, 4 dimethyl benzene).  Commercial xylene is a mixture of the
three forms with meta-xylene being the major component.  Ortho-xylene is
the subject of this report.

Commercial xylene is produced from both petroleum and coal tar.  A typ-
ical petroleum product contains approximately 20 percent ortho-xylene,
while approximately 10 percent-15 percent of xylene manufactured from
coal tar consists of the ortho isomer.  Essentially all xylene in the
U.S. is produced from petroleum.  Ortho-xylene is predominantly used in
the manufacture of phthalic anhydride.  Significant physical properties
are listed in Table 1.^

HEALTH AND WELFARE EFFECTS

Effects on Man

Acute Poisoning   Xylene is an irritant to mucous membranes,  and it is
narcotic in high concentrations.  Actual air concentrations have not,
however, been reported when instances of acute poisoning have occurred.
               2
In one instance  three painters working in a ship's fuel tank were

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overcome by xylene vapor  from  the  paint they were using, in which the
solvent was 90  percent xylene.  The xylene concentration was estimated
to have been 10,000 ppm.  One  of the men died shortly after discovery
and an autopsy  showed pulmonary edema  and intra-alveolar hemorrhages.
The other  two men had temporary hepatic impairment and one had temporary
renal impairment, but both  recovered completely  in two days.
             Table 1.   SIGNIFICANT PROPERTIES OF ORTHO-XYLENE
Synonyms
Xylol, dimethyl benzene
Chemical formula
Molecular weight
Boiling point
Vapor density
Solubility

Explosive limits
Flash point  (closed cup)
Autoignition temperature
At 25°C and  760 mm Hg
     (CH3)2
106.16
143.6°C
1.024 (air = 1.0)
Insoluble in water; miscible in alcohol,
ether, and many organic solvents
17o-6%
17.2°C
501°C
1 ppm =4.34 mg/nf
1 mg/m3= 0.23 ppm
Giddiness, anorexia (lack of appetite) and vomiting were observed in a
                                                                  3
paint-pot cleaner who used a solvent containing 75 percent xylene.   The
remaining 25 percent was made up of ethylbenzene, methylethylbenzene, and
trimethylbenzene.  At head height above the pots the xylene concentration
was 60 to 100 ppm when the pots were cold, and 270 to 350 ppm when they
were warm.  Higher concentrations were encountered when the painter placed
his head inside the pots during cleaning.

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For humans, only one report associates possible narcotic effects with a
                              4
known concentration of xylene.   One of seven volunteers exposed to
230 ppm and one of six exposed to 460 ppm experienced slight lightheaded-
ness without loss of equilibrium or coordination at the end of a 15-
minute exposure period.

Ingestion of xylene has caused acute injury of the liver.   In one case
a man mistakenly drank a small amount of nitrocellulose varnish, in
which xylene was the main diluent, thinking it was water.  He experienced
immediate retro-sternal burning, heat and redness of the face, and some
dyspnea (shortness of breath).  Tests indicated toxic hepatosis with
                                                .*
recovery in about three weeks.

Liquid xylene  is also a skin  irritant, causing erythema, dryness, and
defatting.  Prolonged contact can cause blistering, but absorption through
intact skin is not significant.

Chronic Poisoning   The NIOSH recommended standard for xylene is a time
weighted average exposure of 100 ppm for up to a 10-hour workday, 40-hour
workweek, with a ceiling concentration of 200-pom for 10 minutes.   This
standard is based mainly on the narcotic and irritant actions of xylene.

Effects on Animals

Acute Poisoning - The acute oral toxicity of xylene to animals is less
than that of toluene or benzene.  The oral LD _ has been given as
1.85 ml/kg.   In white mice, narcotic effects have been noted at concen-
trations of about 4000 ppm of ortho-xylene, with a lethal concentration
                                iti
                                8
of about 7000 ppm.   A concentration of 3062 ppm of ortho-xylene for
24 hours was  fatal to some mice.
Chronic Poisoning  - Rats, guinea pigs, monkeys, and dogs were exposed to
770  ppm of ortho-xylene for 8 hours a day, 5 days a week for 30 days;
                                       9
and  to 78 ppm continuously for 90 days.   At the end of the exposures

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 the  animals were  killed.  Sections  of heart,  lung, liver, spleen, and
 kidney were taken from all  species; sections  of brain and spinal cord
.were taken from dogs  and monkeys.   Results of microscopic examinations
 were negative  and no  significant changes were noted in body weight or
 hematologic data.

 Effects  on Vegetation

 Tomato,  barley, and carrot  were exposed to xylene vapor at 1150 ppm for
 1/4,  1/2, 1, and  2 hours.    Barley was the most sensitive while carrots
 were least sensitive, based on percent injury and time of recovery.  The
                                               *
 first noticeable  symptom in all plants was a  darkening of the tips of
 the  youngest leaves,  due presumably to a leakage of sap into the inter-
 cellular spaces.   The darkening then spread to older leaves, and there
 was  a loss of  rigidity with drooping of stems and leaves.

 AMBIENT  CONCENTRATIONS AND  MEASUREMENT

 Ambient  Concentration Estimates

 Although ortho-xylene emissions are greatest  from the solvent usage
 source category,  these sources tend to be small and geographically
 scattered.  Production of ortho-xylene, however, occurs at a few loca-
 tions for which the emissions characteristics can be fairly well defined,
 and which as single point or area sources have a large emission density.

 The  largest installation for isolated ortho-xylene production is located
 near  Houston, Texas,  a city of over one million population,  and it has
 a capacity of about 210 million Ib/yr.  Assuming a 0.5 percent loss, this
 converts to an emission rate of

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 (0.005 emission factor) (210 x IQ6 Ib/yr) (453.6 g/lb)
                   3.1536 x 107 sec/yr
                                            =15.1 g/sec of ortho-xylene.

Some assumptions must be made regarding this ortho-xylene release to the
atmosphere.  First of all, the emissions do not all come from one source
location, but rather from a number of locations within the plant where
ortho-xylene vapor leaks to the atmosphere.  Thus, the emissions can be
characterized as coming from an area source which will be taken to be
100 meters on a side.  Secondly, the emissions, occur at different heights,
and an average emission height of 10 meters is assumed.

Ground level concentrations can then be estimated at locations downwind
of the facility.    To do this a virtual point source of emission is
assumed upwind of the facility at a distance where the initial horizontal
dispersion coefficient equals the length of a side of the area divided
by 4.3.  In this case:

                        o-   = 100m/4.3 = 23.3si
                         yo

Assuming neutral stability conditions (Pasquill-Gifford Stability Class D)
with overcast skies and light winds, the upwind distance of the virtual
point source is approximately 310 meters.  With consideration of the plant
boundary,  it is reasonable to assume that the nearest receptor location
is thus about 500 meters from the virtual point source.  Finally, taking
2 m/sec as an average wind speed, the ground level concentration may be
calculated from:
                              uircr

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                    y         ~.^	  -% / 10 \ ;
                    "•    X'-tN.— y*^/-Nxi«-»r-\^   I ~-j"o C* J
      15.1	
(2)  TT (36) (18.5)
                     = 3.12 x 10"3 g/ra3

for a 10-minute average concentration.  Over a period of an hour this
becomes  (3.12 x 10"3 g/ra3)  (0.72) = 2.25 x 10"3 g/m3 or 0.5 ppm 1-hour
average  concentration.  Over a 24-hour period, the average concentration
might roughly be expected to be about 0.3 ppm.

Ortho-Xylene Measurement Techniques

Analytical methods for measuring ortho-xylene concentrations in air
include  ultraviolet absorption spectrophotometry, colorimetry, and gas
chromatography.  Air is either drawn through a bubbler or passed over
silica gel or charcoal to remove the ortho-xylene from the air.  Sensi-
tivity,  specificity, and accuracy are functions of the sampling method
used and of the sampling interval.  Features of the techniques are
discussed below.

                                        12
Ultraviolet Absorption Spectrophotometry   - Ortho-xylene absorbs ultra-
violet light at a wavelength of 272.0 mfi.  Concentration may be determined
by comparing the absorbance of the sample with the absorbance of known
standards.  In this technique air is collected in a gas washing bottle
containing methanol, which  is immersed in dry ice.  After collection, the
absorbance of ortho-xylene  is determined on a spectrophotometer.  This
method is not/specific for ortho-xylene as other aromatic hydrocarbons
will interfere and is not sensitive enough for air pollution work.  The
lower detection limit is about 10 ppm of ortho-xylene.

                   13
Colorimetric Method   - In this technique air is collected in a special
U-tube containing a solution of formaldehyde and sulfuric acid.  After
collection, the sample is transferred to a volumetric flask and diluted

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with formaldehyde and sulfuric acid.  The optical density of the color
produced is read on a spcctrophotometer at 460 mpi.  The concentration
of the sample is then read from a calibration curve.  Concentrations from
40 to 350 ppm may be determined by this method.  Interferences will result
from other aromatic hydrocarbons.  This method is not sensitive enough
for air pollution work but may be used for industrial hygiene work.

                  14
Gas Chromatography   -aAdsorption of xylene vapor on activated charcoal
with subsequent desorption and analyses by gas chromatograph is the pre-
ferred sampling method for ortho-xylene.  Concentrations in the range
of 5 ppm are readily detectable by this method.  Air is drawn through a
tube containing charcoal on which organic vapors are adsorbed.  The
sample is then desorbed using carbon disulfide, and an aliquot of the
desorbed sample is analyzed using a gas chromatograph.  The presence
and concentration of ortho-xylene are determined from its characteristic
retention time and the area under the curve.

Interferences may result from other organic compounds having similar
retention times; however, this may be overcome by changing the operating
conditions of the instrument, usually the column and/or the column
temperature.

This technique is especially well-suited for air pollution work since
there is no requirement for special chemicals in the field.

SOURCES OF ORTHO-XYLENE EMISSIONS
Ortho-Xylene Production and Consumption   The production of isolated
ortho-xylene in 1974 was 1,045 million pounds   and is expected to decli
in growth during  1975 before  slowly increasing  (6 percent growth by
1978).   '   '    Because of economic conditions  during 1974 production
of ortho-xylene far exceeded  its demand  (789 million pounds).  The only

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outlets  for ortho-xylene are  for phthallc anhydride, exports and miscel-
laneous  uses such as solvents  for agricultural sprays.  The difference
between  production and demand  (256 million pounds) could not be accounted
for even though conversations  were held with several individuals in  the
                  17 18 19
chemical industry.  '  '    The only satisfactory explanation for the
difference is  that the ortho-xylene produced in  1974 was not all consumed
and is being stored for future use when economic conditions improve.*0

Presently, there are nine companies at nine locations who isolate ortho-
xylene from unmixed xylene  (see Appendix A).  The consumption of isolated
ortho-xylene for final products is shown in Table 2.

      Table 2.  ESTIMATED ISOLATED ORTHO-XYLENE CONSUMPTION   1974
                     Product
           Phthalic anhydride
           Exports
           Miscellaneous
           Increase in inventories
                             Total
Million pounds
      667
      117
        5
      256
    1,045
Ortho-Xylene Sources and Emission Estimates

In this report primary sources of emissions of ortho-xylene are estimated
from both unisolated ortho-xylene present in mixed xylene streams, and
from isolated ortho-xylene.  Ortho-xylene is produced solely for the
manufacture of phthalic anhydride; however, it is also a major component
in mixed xylene streams.  The composition of a typical mixed xylene has
             21
been reported   as shown in Table 3.

Mixed xylenes are used primarily to produce the individual isomers, for
solvent usage and for the manufacture of xylene sulfonates and xylidenes.
They are also used as high octane components of gasoline.  See Table 4.
                                10

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           Table 3.  AVERAGE COMPOSITION OF MIXED XYLENE
                                                        21
Toluene
Ethylbenzene
p-xylene
m-xylene
o-xylene
c + aromatic

2.9%
23.7%.
16.77.
35.77.
20.57,
0.57.
100.07.
    Table 4.  ESTIMATED XYLENE CONSUMPTION   197415'17'18)19>20>22
                Product
      Million pounds
1.  Mixed xylenes
    As a source of individual isomers

    Solvent usage
    Xylene sulfonates, xylidenes
    Blended into gasoline
2.  Ethylbenzene
3.  Ortho-xylene
    Phthalic anhydride
    Exports
    Miscellaneous solvent usage
    Inventory
4.  Meta-xylene
5.  Para-xylene
4,328

  809
   35
  619
  667
  117
    5
  256
                5,791
                  500
                1,045
                   99
                2,684
                                11

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Emissions of ortho-xylene result from mixed xylene solvent usage, mixed
xylene production, ortho-xylene production, miscellaneous ortho-xylene
solvent usage and bulk storage.  Total emissions from all categories are
estimated to be 184 million pounds with emissions from mixed xylene pro-
duction and usage accounting for approximately 93 percent of all losses.
See Table 5.

     Table 5.   SOURCES AND EMISSION ESTIMATES OF ORTHO-XYLENE - 1974
                         Source
     Mixed xylene solvent usage
     Mixed xylene production
     Ortho xylene production
     Miscellaneous ortho-xylene solvent usage
     Bulk storage
Million pounds
     166
       6
       5
       5
       2
The major source of ortho-xylene emissions results from its use as a
solvent present in mixed xylene (20.5 percent).  The chief outlet of mixed
xylenes in the solvent market is for industrial paints and thinners.  It
is assumed that all ortho-xylene used as a solvent will evaporate to the
atmosphere.  In 1974 an estimated 809 million pounds of mixed xylenes
                               22
were used for solvent purposes.    Converting this figure to ortho-xylene
will result in emissions of 166 million pounds.

The second major source of emissions results from the manufacture of
mixed xylenes.  Ninety-nine percent of all mixed xylenes are recovered
from petroleum sources and the rest are obtained as a by-product of coke-
oven operations.  Approximately 96 percent of the recovered xylene from
petroleum sources is solvent extracted from reformate and the remaining
4 percent is solvent extracted from pyrolysis gasoline.
                                 12

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Since there are no emission data available concerning these processes,
                                 23
based on other similar processes,   it is estimated that 0.5 percent of
production is lost as mixed xylene resulting in 29 million pounds.
Ortho-xylene emissions account for 20.5 percent of this total or 6 mil-
lion pounds.
The next major source of emissions is from the production of ortho-xylene,
Using the same assumptions as above, 0.5 percent of production is lost
resulting in 5 million pounds of ortho-xylene emissions.

The fourth major source of ortho-xylene emissions is from miscellaneous
solvent usage.  Conversations with the industry have indicated that
approximately 5 million pounds of ortho-xylene were used during 1974 as
either a solvent for pesticide applications or as a solvent for other
    • ! •  A          16,18  .
specialized purposes.       Aj
evaporated to the atmosphere.
                     •I /" -I Q
specialized purposes.  '     Again it is assumed that all solvent is
The last primary source of emissions results from the bulk storage of
ortho-xylene.  Using the emission factors in AP-42 and assuming that all
storage tanks are fixed roof tanks, 2 million pounds of ortho-xylene are
                                23
emitted from bulk storage tanks.

                                               24
Data from a recent report on phthalic anhydride   have indicated that
emissions of ortho-xylene from this process are negligible.  Based on
this report, it is assumed that phthalic anhydride production is not
a primary source of ortho-xylene emissions.

ORTHO-XYLENE EMISSION CONTROL METHODS

The literature does not report specific control equipment for ortho-
xylene emissions, but it does report on control devices for other similar
             25
hydrocarbons.    Two types of control devices are presently used by the
industry to control hydrocarbon emissions:  vapor recovery and incineration.
Both systems have reported efficiencies of at least 95 percent.
                                 13

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Control of hydrocarbon emissions by adsorption on activated charcoal is
generally applied when recovery of adsorbed material is economically
desirable.  Adsorption should be used when concentrations  of hydrocarbons
                          9 fi
are greater than 2500 ppm.    Other applications  are for the control of
very low concentration hydrocarbons that are poisonous  to  catalytic in-
cinerators and for collection and concentration of low  concentration
emissions for subsequent disposal by incineration.  Cost data for the
cases utilizing adsorption are presented in Tables 6 and 7.  The three
cases presented are adsorption with solvent recovery, adsorption with
incineration, and adsorption with incineration plus heat recovery.

Control of xylene emissions by incineration or catalytic oxidation in-
volves direct oxidation of the combustible portion of the  effluent, the
desired ultimate products being water and carbon dioxide.

The primary advantage of catalytic incineration is that extremely small
concentrations of organics can be oxidized with only small amounts of
supplemental fuel required.  The main disadvantages are the higher
capital cost and the poisoning of the catalyst by certain  hydrocarbons.
Cost data for thermal and catalytic incinerators with and  without heat
                                         27
recovery are presented in Tables 8 and 9.

Control of emissions from storage tanks will require the use of floating
roof tanks or venting the emissions to the previously mentioned adsorber
or incinerator.  Emissions from fixed roof tanks can be vented to either
system without any major increase in cost.  If these systems are not
available the fixed roof tanks should be switched to floating roof tanks-
resulting in a 67 percent reduction of emissions.  Figure  1 provides
                                                  27
estimated costs of various gasoline storage tanks. "  These equipment
cost estimates can also be applied to ortho-xylene.  As can be seen,
conversion of fixed roof to floating roof tanks by installation of
internal floating covers is more economical than the installation of
new pontoon floating tanks.
                                 14

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    Table 6.  ESTIMATED INSTALLED COSTS3 OF ADSORPTION SYSTEMS27
Adsorber capacity, SCFM -
based on 25 percent lower
explosive limit
With solvent recovery, $
With thermal incinerator/
No heat recovery, $
With thermal incineration/
Primary heat recovery, $
1,000
74,000
89,500
101,500
10,000
162,300
202,000
255,000
20,000
280,000
344,000
431,000
Costs updated to 1st quarter 1975.
                                                                  O ~7
 Table 7.  ESTIMATED ANNUAL OPERATING COSTSa OF ADSORPTION SYSTEMS
Adsorber capacity, SCFM-
based on 25 percent lower
explosive limit
With solvent recovery, $/yr
With thermal incineration/
No heat recovery, $/yr
With thermal incineration/
Primary heat recovery, $/yr
1,000
13,200
23,400
25,600
10,000
10,479b
64,300
82,000
20,000
37,200b
123,200
141,600
Costs updated to 1st quarter 1975.
Indicates a savings.
                                15

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Table 8.  ESTIMATED INSTALLED COSTS3 OF THERMAL AND CATALYTIC INCINERATORS27
Incinerator capacity, SCFM -
based on 25 percent lower
explosive limit
Installed costs, $
Catalytic without heat recovery
Catalytic with primary heat
recovery
Catalytic with primary and
secondary heat recovery
Thermal without heat recovery
Thermal with primary heat
recovery
Thermal with primary and
secondary heat recovery
1,000

43,500
54,100
68,300
27,200 ,
40,300
54,400
10,000

272,000
306,000
361,800
92,500
144,200
200,000
20,000

504,600
573,900
666,400
137,400
232,600
322,300
   Costs updated to  1st quarter 1975.
           Table 9.   ESTIMATED ANNUAL OPERATING COSTS  OF THERMAL
                     AND CATALYTIC INCINERATORS2?
Incinerator capacity, SCFM -
based on 25 percent lower
explosive limit
Operating costs, $/yr
Catalytic without heat recovery
Catalytic with primary heat
recovery
Catalytic with primary and
secondary heat recovery
Thermal without heat recovery
Thermal with primary heat recovery
Thermal with primary and secondary
heat recovery
1,000
16,200
16,400
19,300
12,000
11,500
14,400
10,000
102,800
78,500
108,700
54,300
36,300
50,800
20,000
195,000
177,900
203,700
96,700
59,200
84,500
   Costs updated to 1st quarter 1975.
                                   16

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    500
    400
•o  300
r~

x
O
u
    200
g
z
    100
         T   I   I   TT~1—T~T~1—T~T~T
               Total Coil Cono Roof Tank Converted

               with  Internal  floating Roof
               Pontoon Floating

               Roof Tank
                                              Cona Roof Tank
                             Internal Float Cover on Existing Cona

                             Roof  Tonic  (Incremental Cost - Conversion]
     Ol   I   f   I   I   I   I   I   I   I   I   I   I   I   f  I   I   I   I   ?

       0             50             100            150            200

                          CAPACITY, barrels  x 1CT3
  Figure  1.   Estimated  installed cost  of ortho-xylene storage

              tanks  (equipment costs  assumed to be  the same as

              gasoline storage tanks)27
                             17

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                                 SECTION  III

                                 REFERENCES


 1.  Am  Ind Hyg Assoc J.  Hygienic Guide Series.  32, October 1971.

 2.  MorleyR., D.W. Eccleston,  C.P. Douglas, W.E.J. Greville, D.J.  Scott,
     and J. Anderson.  Xylene Poisoning   A Report on One Fatal Case and
     Two Cases of Recovery After Prolonged Unconsciousness.  Br Med J.
     3:442-43, 1970.

 3.  Glass, W.I.  Annotation:  A Case of Suspected Xylol Poisoning.  NZ
     Med J.  60:113, 1961.

 4.  Greenburg L., M.R. Mayers,  L. Goldwater, and A.R. Smith.  Benzene
     (Benzol) Poisoning in the Rotogravure Printing Industry in New York
     City.  J Ind Hyg Toxicol.   21:395-420, 1939.

 5.  Browning, E.  Toxicity and  Metabolism of Industrial Solvents.
     Elsevier Publishing Co. (Amsterdam).  1965.

 6.  Occupational Exposure to Xylene:  Criteria for a Recommended Standard.
     HEW Publication Number (NIOSH) 75-168.  1975.

 7.  Lazarew, N.W.   On the Toxicity of Various Hydrocarbon Vapors.  Arch
     Exper Pathol Pharmakol (Germany).  143:223-33, 1929.

 8.  Cameron, G.R., J.L.H. Paterson, G.S.W. de Saram, and J.C.  Thomas.
     The Toxicity of Some Methyl Derivatives of Benzene with Special
     Reference to Pseudocumene and Heavy Coal Tar Naphtha.   J Pathol
     Bacteriol.   46:95-107, 1938.

 9.  Jenkins, L.J.  Jr., R.A.  Jones, and J.  Siegel.  Long-Term Inhalation
     Screening Studies of Benzene,  Toluene, Ortho-Xylene, and Cumene
     on Experimental Animals.   Toxicol Appl Pharmacol.   16:818-23, 1970.

10.  Currier, H.B.   Herbicidal Properties of Benzene and Certain Methyl
     Derivatives.  Hilgardia.   20:19, February 1951.

11.  Turner, D.B.  Workbook of Atmospheric  Dispersion Estimates.   U.S.
     Environmental Protection Agency Publication No. AP-26.  April 1973.
                                  18

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12.  Danbrouskas, T., and W. Cook.  Methanol as the Absorbing Reagent in
     the Determination of Benzene, Toluene, Xylene and Their Mixtures
     in Air.  Amer Ind Hyg Assoc J.  24.:568, 1963.

13.  Hanson, N. , D. Reilly, and H. Stagg.  The Determination of Toxic
     Substances in Air.  W. Heffer and Sons, Ltd.  1965.

14.  Occupational Exposure to Xylene.  U.S. Dept. of Health, Education
     and Welfare. NIOSH.  1975.

15.  Preliminary Report on U.S.  Production of Selected Synthetic Organic
     Chemicals.  U.S. International Trade Commission.  May 16, 1975.

16.  Chemical Profile, Chemical Marketing Reporter.  May 26, 1975.

17.  Conversation with ARCO, Houston, Texas.  September 1975.

18.  Conversation with Cosdon Oil and Chemical, Big Spring, Texas.
     September 1975.

19.  Conversation with Shell Chemical Co., Houston, Texas.  September 1975.

20.  U.S. Exports Schedule B Commodity by County.  U.S. Department of
     Commerce.  December 1974.

21.  Weedman, J.A., and R.A. Findlay.  How to Separate Xylenes for Profit.
     Petroleum Refiner.  November 1958.

22.  Chemical Economics Handbook.  Stanford Research Institute.  September
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23.  Compilation of Air Pollution Emission Factors.  U.S. Environmental
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24.  Engineering and Cost Study of Air Pollution Control for the Petro-
     chemical Industry.  Phthalic Anhydride Manufacture from Ortho-
     Xylene.  U.S. Environmental Protection Agency Report No.
     450/3-73-006-g.

25.  Profitably Recycling Solvents from Process Systems.  Pollut Eng.
     Hoyt Manufacturing Co., Westport, Mass.  October 1973.

26.  Lauber, J.  The Control of Solvent Vapor Emissions.  N.Y. State
     Department of Health.   January 1969.

27.  Hydrocarbon Pollutant Systems Study, Volume 1, MSA Research Corp.
     October 1972.
                                  19

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                              APPENDIX A
                      ORTHO-XYLENE MANUFACTURERS
Arco
Chevron
Commonwealth
Exxon
Monsanto
Phillips
Shell
Sun
Tenneco
Houston, Texas
Richmond, California
Panuelas, Puerto Rico
Baytown, Texas
Alvin, Texas
Guayama, Puerto Rico
Houston, Texas
Corpus Christi, Texas
Chalmette, Texas
                Total
                                                       Annual capacity,
                                                        million pounds
  210
  130
  150
  130
   30
  130
  200
  160
  155
1,295
                                20

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