Document ID: EPA-HQ-OAR-2012-0360-0111
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2015-03-18T04:00Z

MEMORANDUM

DATE:	October 17, 2014

SUBJECT:	Revised Technology Review for the Off-Site Waste and Recovery Operations Tanks

FROM:	Lesley Stobert, EC/R Inc.

TO:		Paula Hirtz, EPA/OAQPS/SPPD

The EPA proposed amendments to off-site waste and recovery operations (OSWRO) national emissions standards for hazardous air pollutants (NESHAP) on July 2, 2014, based on residual risk and technology reviews conducted for the source category. The purpose of this memorandum is to present a revised analysis related to the technology review for tanks at OSWRO facilities, considering comments submitted during the public comment period for the proposed OSWRO NESHAP amendments.

1.0	INTRODUCTION	

On July 2, 2014 (79 FR 37850), the EPA proposed amendments to the OSWRO source category following the results of a review required by section 112(d)(6) of the CAA, which directs the EPA to review previously issued NESHAP regulations and to revise them as necessary (taking into account developments in practices, processes and control technologies) no less frequently than every 8 years. Section 112(f)(2) of the CAA requires the EPA to assess, within 8 years of promulgation of the original NESHAP for major sources and area sources subject to MACT, the remaining risks due to emissions of HAP from these source categories and determine whether the emissions standards provide an ample margin of safety to protect public health. These reviews are collectively referred to as residual risk and technology reviews (RTRs).

For the July 2014 proposal, a technology review for tanks at OSWRO facilities was conducted.  Under CAA section 112(d)(6), the EPA proposed to require more stringent emissions controls for tanks of certain capacities storing materials above a specified vapor pressure. Following the July 2014 proposal, the EPA received comments from one industry trade association challenging some of the data and assumptions used in the analysis of emissions reduction and costs associated with the emissions controls for these tanks. We have considered these comments and revised certain aspects of our technology review analysis for OSWRO tanks. 

2.0	TANKS RE-ANALYSIS

2.1 	Tanks at OSWRO Facilities

Tanks are used for many different applications at OSWRO facilities to accumulate, store or treat off-site materials. The amount of HAP emissions from tanks depends on the type of material in the tank, the type of tank (e.g., fixed roof tanks, internal floating roof tanks, external floating roof tanks), the methods used to fill and empty the tank, and the number of turnovers per year.

Emissions of HAP from fixed roof tanks and floating roof tanks are the result of working and breathing losses. Working losses occur when vapors are displaced by a rising level of liquid in the tank. Breathing losses occur as a result of liquid level changes due to fluctuations in ambient temperature or pressure. The quantity of emissions from tanks depends greatly on the volatility of the organic material in the tanks and whether the tanks are vented to the atmosphere, equipped with a pressure-vacuum relief valve, vented to an air emission control device, or fitted with a floating roof.

2.2 	Summary of Existing MACT Level of Control

The current OSWRO MACT standards for tanks require either Level 1 or Level 2 controls, depending on the tank capacity and the vapor pressure of the materials in the tank. Tanks subject to Level 1 control requirements are required to be equipped with a fixed roof designed to form a continuous barrier over the entire surface area of the liquid in the tank, with no visible cracks, holes, gaps, etc., between roof section joints or where the roof and tank wall meet. Openings in the roof must be equipped with a closure device or connected to a closed vent system and routed to a control device. The fixed roof and its closure devices are subject to routine visual inspection and repair requirements.

For tanks subject to Level 2 control requirements, one of the following five control alternatives must be used: (1) equip the fixed roof tank with an internal floating roof; (2) equip the fixed roof tank with an external floating roof; (3) equip the tank with a vapor-tight cover and vent to a control device that has a HAP removal or destruction efficiency of 95 percent; (4) use a pressure tank; and (5) locate the tank inside a permanent total enclosure (PTE) that is vented to a combustion control device that has a HAP destruction efficiency of 95 percent.

Tanks used to manage a waste stabilization process are subject to Level 2 requirements.  Other tanks are subject to Level 1 or Level 2 controls as shown below in Table 1.
                                       
     Table 1. Tank Control Levels for Tanks at Existing and New Facilities
Current OSWRO MACT Requirements
                            Applicability Threshold
                                 Control Level

                                     Size 
                                    (m[3])
                             Vapor Pressure (kPa)
                                       
Existing Sources
                                 Less than 75
                                   < 76.6
                                       1

                                       
                                   >= 76.6
                                      2*

                           75 <= capacity < 151
                                   < 27.6
                                       1

                                       
                                   >= 27.6
                                       2

                               151 <= capacity
                                   < 5.2
                                       1

                                       
                                    >= 5.2
                                       2
New Sources
                                 Less than 38
                                   < 76.6
                                       1

                                       
                                   >= 76.6
                                      2*

                           38 <= capacity < 151
                                   < 13.1
                                       1

                                       
                                   >= 13.1
                                       2

                               151 <= capacity
                                   < 0.7
                                       1

                                       
                                    >= 0.7
                                       2
* Except that fixed roof tanks equipped with an internal floating roof and tanks equipped with an external floating roof shall not be used

2.3	Proposed Standard for Tanks

At proposal, we identified two potential developments in existing practices and control techniques not currently required by the OSWRO MACT standards for tanks at existing sources. 
One option we evaluated (Option 1) was to revise the applicability of the OSWRO requirements to use the same thresholds for Level 2 control as the thresholds for control required by other MACT standards, specifically the Hazardous Organic NESHAP (HON). Based on information received from the industry as part of a CAA section 114 survey, which showed that the industry primarily uses fixed roof tanks vented to control devices, under Option 2 we also considered the impacts of requiring a 98 percent emissions reduction for tanks required to use Level 2 control, rather than the currently required 95 percent emissions reduction, along with the revised capacity and vapor pressure thresholds of Option 1. Based on the estimated control costs and emissions reductions, revisions to the standards for tanks at existing sources to require Option 1 were proposed. Table 2 presents a summary of the tank size and vapor pressure thresholds considered for existing sources under both options.

Table 2. Storage Tank Size Applicability Threshold Alternatives for Existing Sources
Regulatory Options
                            Applicability Threshold
                                 Control Level
                             Option 1 Requirements
                             Option 2 Requirements

                                    If Size
                                   (m[3]) is
                          And Vapor Pressure (kPa) is
                                       
                                       
                                       
Options 1 and 2
                                 Less than 75
                                   < 76.5
                                       1
                                  Fixed roof 

                                       
                                   >= 76.5
                                     2[a]
                                95% control[b] 
                                98% control[b]

                           75 <= capacity < 151
                                   < 13.1
                                       1
                                  Fixed roof

                                       
                                   >= 13.1
                                       2
                                95% control[b] 
                                98% control[b]

                               151 <= capacity
                                   < 5.2
                                       1
                                  Fixed roof

                                       
                                    >= 5.2
                                       2
                                95% control[b]
                                98% control[b]
[a] Except that fixed roof tanks equipped with an internal floating roof and tanks equipped with an external floating roof shall not be used
[b] Control efficiency would apply to tanks vented to a control device and tanks inside a permanent total enclosure (PTE) that are vented to a combustion control device; use of an internal or external floating roof or a pressure tank would still be available control options.

2.4 	Revised Estimation of Tank Emissions

Based on comments regarding the proposed revised tank standards from the Cement Kiln Recycling Coalition (CKRC), an industry trade association, we have revised our analysis of tank emissions for tanks with capacities greater than or equal to 75 m[3], but less than 151 m[3], if the vapor pressure of the stored material is 13 kPa or greater. While we have not revised our estimate of the number of tanks in this size and vapor pressure range that would require controls under Option 1, we have revised some of the parameters used to estimate emissions potential from these tanks using the EPA's TANKS 4.09d program.  

To estimate the number of tanks existing in the OSWRO source category with a capacity range of 75 m[3] to 151 m[3] and with a vapor pressure of stored material between 13.1 kPa and 27.6 kPa (i.e., those tanks with a stored material vapor pressure of 2.76 kPa are already regulated under the current NESHAP), OSWRO CAA section 114 survey data was used and then scaled up to nationwide values based on the number of known OSWRO facilities. Table 3 shows the estimated number of tanks in this size and vapor pressure range and how this estimate was calculated. Although CKRC commented that they believe there are more tanks in this size and vapor pressure range than the estimate used at proposal, we received no data to support this assertion, and many of the CKRC member companies submitted data through the CAA section 114 survey, which was used in developing this estimate of tanks in this size and vapor pressure range in the source category.

  Table 3. Estimated OSWRO Tank Population Based on CAA 114 Survey Responses
                           Tank Size/Vapor Pressure 
            Estimated Number of Tanks in the OSWRO Source Category
Estimated Number of Tanks in the OSWRO Source Category that Would Require Level 2 Controls
                                  Explanation
                   75 - 151 m[3] and 13.1 <= kPa < 27.6
                                   21 tanks
                                   14 tanks
One of 15 facilities responding to the survey has tanks with this size and vapor pressure. Total number of tanks for this facility is 7. Scaling up to 49 facilities in the source category, 1/15 x 49 = 3 facilities have 7 tanks or 21 total tanks. 

The one facility reporting tanks of this size and vapor pressure already uses Level 2 emissions controls for these tanks. It is assumed that the tanks of this size and vapor pressure at other facilities are not already controlled with Level 2 controls. 

We estimated the emission potential from a model tank in the capacity range of 75 m[3] to 151 m[3] and vapor pressure between 13.1 kPa and 27.6 kPa using the EPA's TANKS 4.09d program, which is a software tool that calculates HAP emissions from fixed and floating roof tanks. The parameters shown in Table 4 were used as inputs to the TANKS program and were based on information reported in the OSWRO CAA section 114 survey responses and on comments from CKRC. The specific changes incorporated since proposal include: 

   * Tank conservation vent pressure setting of 0.5 psi rather than 0.03 psi to reflect probable vent settings currently in place under control Level 1; 
   * Tank location of Concordia, KS, rather than Houston, TX. Concordia, KS is the closest city to the geographic center of the continental U.S. included in the TANKS program and is more representative of national average temperatures;
   * Revised mix of tank constituents to include non-HAP contents, with an overall HAP content revised to 60 percent from 100 percent to more accurately reflect typical OSWRO tank contents. 

We note that although CKRC commented that they believe the estimated throughput is too high, we have not changed our estimate. The commenter did not provide detailed information to support the use of a different value. Our estimate of 4,996,918 gal/yr was developed from data reported in the supporting documentation for the proposed storage tank uniform standards, and data from the one facility reporting tanks in this size and vapor pressure range is similar to this estimate. 

The revised estimated emission potential for tanks with capacities greater than or equal to 75 m[3], but less than 151 m[3], if the vapor pressure of the stored material is between 13.1  kPa and 27.6 kPa is shown in Table 4. See the Appendix to this document for more information on the inputs used and outputs obtained from the TANKS 4.09d program.

                                       
              Table 4. Estimation of Tank HAP Emission Potential
                         Size and Vapor Pressure Range
                            Capacity[1] (gal/m[3])
                                Height[1] (Ft)
                               Diameter[1] (ft)
                              Throughput[2] (gal)
                     Tank Contents Vapor Pressure[3] (kPa)
                                  Location[4]
                               Tank Contents[5]
                  Speciated and Total Emission Potential[6] 
                                    (lb/yr)
                                     Tank
                >=75 to < 151 m[3] and 13.1<kPa<27.6 
                                  25,000 gal
                                  (94.6 m[3])
                                     28.4
                                     12.3
                                   4,996,918
                                     14.86
                                 Concordia, KS
10% methanol*
                                      361
                                       
                                       
                                       
                                       
                                       
                                       
                                       
20% methylene chloride*
                                     2,863

10% tetrachloroethylene*
                                      52

10% toluene*
                                      83

10% trichloroethane (1,1,1)*
                                      417

20% acetone 
                                     1,482

6.66% cyclohexene
                                      204

6.67% isopropyl alcohol
                                      79

6.67% methyl ethyl ketone
                                      182

                                                                Total Emissions
                                     5,722

                                                            Total HAP Emissions
                                     3,776
[1] Capacity, height and diameter based on average of CAA section 114 survey response data for tanks meeting these thresholds.
[2] Due to insufficient OSWRO survey response data (data not reported or units not reported), throughput estimated via linear interpolation from data reported in the supporting documentation for the proposed storage tank uniform standards (Memorandum from Randall, D., RTI International, to Parsons, N., EPA/OAQPS. Survey of Control Technology for Storage Vessels and Analysis of Impacts for Storage Vessel Control Options. January 20, 2012. EPA Docket No. EPA-HQ-OAR-2010-0871-0027). This value is similar to the value obtained from the average of the 7 tanks at the one facility reporting tanks in this size and vapor pressure range, which reported an average of 19.161 tons of annual throughput. Based on the tank emissions reported by this facility, the average weight per gallon of stored material is 8 lbs/gal, resulting in an average throughput of 4,790,143 gal. 
[3] Vapor pressure was determined with TANKS4.0.9d based on the tank contents.
[4] Location assumed as Concordia, KS, the closest city to the geographic center of the continental U.S. to be representative of a national average.
[5] Chemicals included are based on comments from CKRC. The relative amount of each chemical varied to give more weight to chemicals with higher vapor pressures to make the overall vapor pressure of the tank be above the 13.1 kPa threshold for regulation. * Denotes chemicals that are HAP.
[6] Uncontrolled emissions from TANKS 4.0.9d.
To determine the nationwide emissions reduction that would be achieved under Option 1, we first determined the nationwide HAP emissions from the additional tanks that would require Level 2 control under Option 1. This was calculated using the estimated tank population shown in Table 3, the Level 1 HAP emissions per tank for this size and vapor pressure type shown in Table 4, and the estimated number of uncontrolled tanks within the estimated tank population shown in Table 3. This calculation is shown below:
Baseline HAP EmissionsTanks: 75-151 m3 and 13.1-27.6 kPa=14 tanksx3,776lbyr2,000lbton=26.4 tpy

The Option 1 emissions reduction requirement is 95 percent. Application of a 95 percent emissions reduction to the uncontrolled emissions calculated above results in a reduction of 26.4 tons per year (tpy). 

2.5 	Revised Estimate of Option 1 Costs

Based on comments from CKRC, we have revised our analysis of tank control costs under Option 1. As described above, Option 1 considers lowering the vapor pressure threshold to apply to more storage tanks, which requires additional storage tanks to control emissions with Level 2 controls. To estimate the costs for requiring these additional storage tanks to use Level 2 controls, it was assumed that the emissions from these tanks would be routed to an existing control device at the facility already used to control emissions from other tanks. We previously assumed that the only additional costs associated with Option 1 would be for ductwork for the estimated 21 additional tanks that would be captured under the new vapor pressure threshold. 

We have made several revisions to our prior cost estimate. First we have revised the analysis to include costs for only the assumed 14 tanks without Level 2 emissions controls. CKRC commented that the EPA should have included a flame arrestor for each tank to prevent back-flash to the tanks. We have revised the estimated costs to include costs for flame arrestors. However, since one flame arrestor typically is installed in the piping system that serves several tanks, we have assumed that two arrestors per facility (i.e., two arrestors to serve the 7 tanks at each facility) would be installed. In addition, we have added costs associated with adding a carbon adsorption system. While some air pollution control devices may have sufficient capacity to control additional tanks, it is possible that the facilities with these tanks may not have excess capacity to control emissions from these tanks. In this case, depending on the control device(s) already in place, an additional carbon adsorption unit may be needed or could be used for these tanks rather than other control devices already at the facility. Based on the relatively low flow rate expected for these tanks and the costs of the different types of carbon adsorption systems, we assumed carbon canisters would be used for these tanks. We did not add, as the commenter suggested, costs for a nitrogen blanketing system, as these systems are not required and could already be in place on these tanks.

Based on information contained in the EPA Air Pollution Control Cost Manual, the revised nationwide capital costs associated with the Tank Option 1, including ductwork, flame arrestors, and carbon adsorption canisters, were estimated to be $139,000 with nationwide annual costs of $192,000. See the Appendix to this document for more information about how these costs were determined. The revised annual HAP emissions reduction estimate for Option 1 is 26.4 tpy, and the revised estimate of the annual cost per ton of HAP removed is $7,000. These cost estimates are summarized in Table 5.

Table 5. Revised Nationwide Costs and Emission Reductions of Regulatory Option 1 Tanks
                            Regulatory Alternative
                         HAP Emissions Reduction (tpy)
                               Capital Cost ($)
                             Annual Costs 
($/yr)
                        Cost Effectiveness ($/ton HAP)
                  Incremental Cost Effectiveness ($/ton HAP)
Option 1:  (HON TS/VP thresholds, 95%  control)[1]
                                     26.4
                                   $139,497
                                   $191,886
                                    $7,268
                                     -----
      [1] The costs associated with this option are for ductwork, flame arrestors and a carbon adsorption system (canisters).
      
      

                                   Appendix

TOTAL ANNUAL COST SPREADSHEET PROGRAM--STRAIGHT DUCTWORK [1]

COST BASE DATE:  CEPCI 1993 [2]

                                                                          359.2
                                                                               

COST ESCALATION: CEPCI 2013 [3]

                                                                          567.3
                                                                               

INPUT PARAMETERS

   Inlet stream flowrate (acfm):[4]

                                                                            729
                                                                               

   Duct velocity (ft/min): [5]

                                                                           3840
                                                                               

   Duct length (ft): [6]

                                                                            150
                                                                               

   Material of construction: [7]

304 SS Sheet

   Insulation thickness (in.): (text input) [8]

                                                                              0
                                                                               

   Duct design: [9]

Circ.-spiral

   Cost equation parameters: [10]

          a:
                                                                           1.56
                                                                               

          b:
                                                                              1
                                                                               

   Cost equation form: [11]

                                                                              1
                                                                               

   Control system installation factor: [12]

                                                                            1.5
                                                                               

   (if no system, enter '0')
   Fan-motor combined efficiency (fraction):

                                                                            0.6
                                                                               

DESIGN PARAMETERS

   Duct diameter (in.):

                                                                     5.89777904
                                                                               

   Pressure drop (in. w.c.): [13]

                                                                    5.314321378
                                                                               

CAPITAL COSTS

Equipment Cost ($)--base:

                                                                         $1,380
                                                                               

    '      '    ' --escalated:

                                                                         $2,180
                                                                               

Purchased Equipment Cost ($):

                                                                         $2,354
                                                                               

Total Capital Investment ($): [14]

                                                                         $3,531
                                                                               

====================================================================

ANNUAL COST INPUTS

   Operating factor (hours/year):

                                                                           8760
                                                                               

   Electricity price ($/kWhr): [15]

                                                                          0.067
                                                                               

   Annual interest rate (fractional):

                                                                           0.07
                                                                               

   Ductwork economic life (years):

                                                                             15
                                                                               

   Capital recovery factor (system):

                                                                    0.109794625
                                                                               

   Taxes, insurance, admin. factor:

                                                                           0.04
                                                                               

ANNUAL COSTS

 Cost ($/yr)
   Wt.Fact.

Electricity

                                                                           $445
                                                                    0.457075677
                                                                               
Taxes, insurance, administrative

                                                                           $141
                                                                    0.144978319
                                                                               
Capital recovery

                                                                           $388
                                                                    0.397946003
                                                                               
------------------------------------------------------------------------------------------------------------------------
Total Annual Cost

                                                                           $974
                                                                              1
                                                                               

Notes:

[1] Data used to develop this program were taken from 'OAQPS Control Cost Manual', 5th edition, Chapter 10.  Prices are for CIRCULAR straight ductwork, only.
[2] Base ductwork costs reflect this date.
[3] PPI = Producer Price Index PCU 3444#1 ('Air-conditioning ducts and stove pipe') for year and quarter shown.  Ductwork equipment cost has been escalated to this date via this PPI.
[4] Median flow rate of tanks controlled by thermal oxidizers in OSWRO CAA section 114 survey
[5] See 'Manual,' pp. 10-30 to 10-33.
[6] Duct length is a site-specific parameter that can vary from < 10 to > 1000 ft.
[7] Choices available are: carbon steel sheet (galv. CS sh.), stainless steel sheet (304 SS sh.), coated carbon steel plate (coat. CS pl.), 304 stainless steel plate (304 SS pl.), polyvinyl chloride (PVC), and fiber-reinforced plastic (FRP)
[8] Choices are: 0, 1, and 3.
[9] Choices are: circular spiral (circ.-spiral) and circular longitudinal (circ.-long.)
[10] Equation type and parameters depend on duct material of construction.  Parameters reflect 2nd quarter 1993 costs.  See 'Manual,' pp. 10-44 to 10-49.
[11] Choices are: power function (1) and exponential (2).
[12] Installation factor depends on control device ductwork is supporting.  This factor, when multiplied by Purchased Equipment Cost, yields Total Capital Investment (TCI).  If ductwork is installed alone, factor is 1.25 to 1.50.  (Default = 1.50.)  See 'Manual'.
[13] Pressure drop applies ONLY to circular, spiral-wound galvanized duct with 10 joints per 100 feet.  For pressure drop data for other duct types, see 'Manual,' Chapter 10.
[14] Product of installation factor and Purchased Equipment Cost.  Costs are presented both in terms of 2nd quarter '93 and above escalation date.  Latter costs are based on Producer Price Index PCU 3444#1 ('Air-conditioning ducts and stove pipe')
[15] 2012 Table 5.3. Average Retail Price of Electricity to Ultimate Customers: Industrial http://www.eia.gov/electricity/monthly/epm_table_grapher.cfm?t=epmt_5_3

TOTAL ANNUAL COST --DETONATION ARRESTOR

CAPITAL COSTS

Equipment Cost ($):[1]

                                                                        $10,000
                                                                               
Sales Tax and Freight  (fractional):

                                                                           0.08
                                                                               
Purchased equipment cost:

                                                                     $10,800.00
                                                                               
Direct and indirect installation costs (fractional):[2]
                                                                            0.5
                                                                               
Direct installation costs ($):

                                                                      $5,000.00
                                                                               
Total Capital Investment ($): [14]

                                                                        $15,800
                                                                               
====================================================================
ANNUAL COST INPUTS

   Operating factor (hours/year):

                                                                           8760
                                                                               
   Annual interest rate (fractional):

                                                                           0.07
                                                                               
   Economic life (years):

                                                                             15
                                                                               
   Capital recovery factor (system):

                                                                    0.109794625
                                                                               
   Taxes, insurance, admin. factor:

                                                                           0.04
                                                                               
   Maintenance labor rate ($/hr):[3]

                                                                         54.117
                                                                               
   Maintenance labor factor (hr/year):

                                                                              4
                                                                               

ANNUAL COSTS

 Cost ($/yr)
   Wt.Fact.
Taxes, insurance, administrative

                                                                           $632
                                                                    0.244655604
Capital recovery

                                                                         $1,735
                                                                    0.671546755
Maintenance labor

                                                                           $216
                                                                               
------------------------------------------------------------------------------------------------------------------------
Total Annual Cost

                                                                         $2,583
                                                                    0.916202359
                                                                               

Notes:

[1] Based on equipment price stated by commenter CKRC, docket ID EPA-HQ-OAR-2012-0360-0066
[2] Based on 'OAQPS Control Cost Manual', 5th edition, Section 2, Chapter 1, page 1-50 for equipment that would have similar installation costs (hoods and ducts)
[3] May 2013 National Industry-Specific Occupational Employment and Wage Estimates NAICS 325000 - Mean of Installation, Maintenance and Repair Occupations http://www.bls.gov/oes/current/naics3_325000.htm plus 110% overhead

Carbon Working Capacity Calculation
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
INPUT PARAMETERS:
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
   Inlet stream flowrate (acfm):[1]
                                                                               
                                                                           8.90
                                                                               
                                                                               
                                                                               
                                                                               
   Inlet stream temperature ([o]F):[2]
                                                                               
                                                                             78
                                                                               
                                                                               
                                                                               
                                                                               
   Inlet stream pressure (atm):[3]
                                                                               
                                                                              1
                                                                               
                                                                               
                                                                               
                                                                               
   Inlet VOC flowrate (lb/hr):[4]
                                                                               
                                                                          4.573
                                                                               
                                                                               
                                                                               
                                                                               
   VOC molecular weight (lb/lb-mole):[4]
                                                                          70.57
                                                                               
                                                                               
                                                                               
                                                                               
   VOC inlet volume fraction:
                                                                               
                                                                   4.767688E-02
                                                                               
                                                                               
                                                                               
                                                                               
   VOC inlet partial pressure (psia):
                                                                               
                                                                         0.7007
                                                                               
                                                                               
                                                                               
                                                                               
   Freundlich isotherm equation constants for VOC (see Table 1 below):
                                                                               
                                                                               
                                                                               
     VOC number (enter Table 1 # or zero, if no data):
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
      K:[5]
                                                                          3.223
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
      M:[5]
                                                                          0.414
                                                                               
                                                                               
                                                                               
                                                                               
DESIGN PARAMETERS:
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
   Carbon equilibrium capacity--Freundlich (lb VOC/lb carb):
                                                                         2.7819
                                                                               
                                                                               
                                                                               
                                                                               
   Carbon working capacity (lb VOC/lb carbon):
                                                                         1.3909
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
[1] Flow rate calculated using 219.6 turnovers/yr and 22754.81 gal for working loss and breathing loss emission rate (0.0266 lb/hr) and vapor density (0.0274 lb/ft3) for 7 tanks
[2] Assumed ambient temperature
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
[3] Assumed ambient pressure
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
[4] Based on model tank emissions
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
[5] The K and M constants were calculated using a mole fraction weighting of the emission components (see "Heat content - mid tanks").
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
Table 1.    Freundlich Constants for Selected Compounds.  
                                                                               
                                                                               
                                                                               
                                                                               
These constants fit the following equation: Q  =  K(P)^M  where:  Q = equilibrium adsorption capacity (lb/lb carbon),  P  = VOC partial pressure (psia at 1 atm & listed temperature)
                                                                               
                                                                               
                                                                               
                                                                               
                                                                               
                           Correlation Range (psia)
 VOC  name
   VOC number
                                       K
                                       M
Temperature (F)
                                    Minimum
                                    Maximum
Benzene
                                     1001
                                     0.597
                                     0.176
                                      77
                                    0.0001
                                     0.05
Chlorobenzene
                                     1002
                                     1.05
                                     0.188
                                      77
                                    0.0001
                                     0.01
Cyclohexane
                                     1003
                                     0.508
                                     0.210
                                      100
                                    0.0001
                                     0.05
Dichloroethane
                                     1004
                                     0.976
                                     0.281
                                      77
                                    0.0001
                                     0.04
Phenol
                                     1005
                                     0.855
                                     0.153
                                      104
                                    0.0001
                                     0.03
Trichloroethane
                                     1006
                                     1.06
                                     0.161
                                      77
                                    0.0001
                                     0.04
Vinyl chloride
                                     1007
                                     0.200
                                     0.477
                                      100
                                    0.0001
                                     0.05
m-Xylene (low-pressure range)
                                     1008
                                     0.708
                                     0.113
                                      77
                                    0.0001
                                     0.001
m-Xylene (high-pressure range)
                                     1009
                                     0.527
                                    0.0703
                                      77
                                     0.001
                                     0.05
Acrylonitrile
                                     1010
                                     0.935
                                     0.424
                                      100
                                    0.0001
                                     0.015
Acetone
                                     1011
                                     0.412
                                     0.389
                                      100
                                    0.0001
                                     0.05
Toluene
                                     1012
                                     0.551
                                     0.110
                                      77
                                    0.0001
                                     0.05
Note: This program has been based on data and procedures in Chapter 4 of the OAQPS CONTROL COST MANUAL (5th edition).

Carbon Adsorption Canister System (1,000 lb Canister System)

COST BASE DATE:  CEPCI 1999

                                                                          390.6
                                                                               
COST ESCALATION: CEPCI 2013

                                                                          567.3
                                                                               

Capital Costs

-- Carbon canister equipment cost (1,000 lb carbon): ($1999)[a]

                                                                         $5,600
                                                                               
-- Carbon canister installation cost (1,000 lb carbon): ($1999)[a]

                                                                         $3,200
                                                                               
-- Carbon canister equipment cost (1,000 lb carbon): ($2013)

                                                                         $8,133
                                                                               
-- Carbon canister installation cost (1,000 lb carbon): ($2013)

                                                                         $4,648
                                                                               

Purchased Equipment Cost ($): ($2013)

                                                                         $8,784
                                                                               
Total Capital Investment ($): ($2013)[b]

                                                                        $13,432
                                                                               

-- Carbon canister, total (lb)

                                                                           1000
                                                                               
-- Inlet VOC flowrate (lb/hr)

                                                                          4.573
                                                                               
-- Carbon working capacity (lb VOC/lb carbon)[c]

                                                                         2.0864
                                                                               
-- Days per canister (days/canister)

                                                                          19.01
                                                                               
-- Number of canister exchanges per year

                                                                           19.2
                                                                               

Annual Costs

Cost of carbon replacement ($/lb)($1999)[d]

                                                                           2.00
                                                                               
Cost of carbon replacement ($/lb)($2013)

                                                                           2.90
                                                                               
Annual cost of carbon replacement

                                                                        $81,005
                                                                               
Annual maintenance[e]

                                                                           $940
                                                                               
Capital recovery[f]

                                                                         $1,475
                                                                               
Taxes, insurance, administrative[g]

                                                                           $537
                                                                               
Total Annual Cost (without credits)

                                                                        $83,957
                                                                               

[a]  Cost from Section 1.3.2 of Carbon Adsorbers from the EPA Control Cost Manual
[b]  Includes vessel, instrumentation, sales tax, and freight

[c]  Assumes 75% of the equilibrium capacity

[d]  Average carbon cost from Section 1.3.2 of Carbon Adsorbers from the EPA Control Cost Manual
[e]  Assumes 7% of installed capital cost

[f]  Assumes 15 year equipment life and 7% interest

[g]  Assumes 4% of installed capital cost

Total Tank Control Costs

Total Capital Investment ($): ($2013)

1,000 lb canister system
                                                                        $13,432
                                                                               

ducts
                                                                        $24,717
                                                                               

flame arrestor
                                                                        $31,600
                                                                               

                                                                        $69,749
per facility

                                                                       $139,497
per source category
Total Annual Cost (with credits)

1,000 lb canister system
                                                                        $83,957
                                                                               

ducts
                                                                         $6,819
                                                                               

flame arrestor
                                                                         $5,166
                                                                               

                                                                        $95,943
per facility

                                                                       $191,886
per source category