MEMORANDUM 

TO: Docket No.: EPA-HQ-OAR-2010-0786 

DATE: September 2, 2010 

SUBJECT: Residual Risk and Technology Review (RTR) 

Cost Analyses for Add-on Controls for Surface Coating Operations at 

Shipbuilding and Ship Repair Facilities 

FROM: Kaye Whitfield, EPA/OAQPS/SPPD/NRCG 

The purpose of this memorandum is to present the estimated emissions reductions, costs, and 

cost effectiveness of add-on controls for certain types of surface coating operations at 

shipbuilding and ship repair facilities subject to MACT subpart II. Two add-on control options 

were analyzed: 1) the addition of spray booths equipped with an RTO system for facilities that 

have new construction operations with large ship component/module painting operations, and 2) 

installing RTO equipped enclosures large enough to enclose an entire ship (or large portion of a 

ship) during shipside coating. 

The shipbuilding and ship repair source category includes facilities (shipyards) that vary greatly 

in size and operations. The location of surface coating operations in a shipyard depends on many 

factors, including the size of the shipyard and whether a ship is being built or repaired. In new 

construction operations, assembly is usually modular, and coating is done in several stages at 

various locations, including outdoors on assembled ships (dockside coating operations). During 

ship repair and maintenance operations, most of the coatings are applied shipside, including 

along docks, inside dry docks and graving docks, and along marine railways. 

I. ROTARY ADSORPOTION/RTO SYSTEM – COATING BOOTH 

The use of spray booths at a facility is generally only applicable when coating ship parts 

indoors (usually during new ship construction as smaller components are put together 

into larger modules and spray painted) and not during shipside coating operations. Spray 

booths can vary significantly in size, number, and exhaust rates. Some spray booths are 

partially enclosed, so emissions may not be fully captured by the enclosure. In general, 

facilities that use compliant coatings do not have add-on controls on spray booths. One 

1 
shipyard in the U.S., the NASSCO facility in San Diego, CA, has been identified to have 

installed spray booths.1

 

The cost analysis for the addition of spray booths equipped with a combination rotary 

adsorption/regenerative thermal oxidizer (RTO) system is provided below. For the 

purposes of this analysis, it was estimated that an average shipyard that is doing new 

construction would need to build or install three large spray booths. Each enclosed spray 

booth is vented to its own rotary concentrator, which is then followed by the RTO. The 

estimated costs are based on capital and operating costs provided by vendors and 

provided in Attachment 1. 

A. Capital Costs 

The capital cost of the spray booths were based on a quote from Finish Pro Spray Booths, 

provided in Attachment 1, and scaled up to dimensions 100 ft x 80 ft x 65 ft; the quote 

does not include shipping or installations costs.2 The capital costs of a rotary 

adsorption/RTO system is based on quotes from Munters and includes capital cost for the 

concentrator, filters, process fan, controls, integrated desorption heater, integrated RTO, 

and startup services and is based on a skid mounted system for easy installation. 

Additional capital costs to account for interest, taxes, and engineering were based on a 25 

percent estimate from the OAQPS cost manual were included for the spray booths and 

the RTO system. Table 1 provides capital costs based on Munters’ estimates (provided in 

Attachment 1). As shown in Table 1, operating costs are greater for smaller systems 

because costs associated with engineering design, controls, instrumentation, and startup 

labor are the same regardless of a system’s size. 

Table 1. Capital and Operating costs of rotary adsorption/RTO system. 

Airflow Range (cfm) $/cfm* Range ($) 

<10,000 30 < 300K 

10,000 – 20,000 25 250K-500K

20,000 – 40,000 20 400K-800K

40,000 – 60,000 18 720K1.08M 

60,000 – 80,000 15 900K-1.2M 

>80,000 13 >1.04M 

 

1

 See the Technology Review for more information on this facility. 

2

 Dimensions based on booths located at the NASSCO facility in an email from Art Gonzales on May 11, 2008. 

2 
 *Cubic feet per minute (cfm) 

B. Operating Costs

Operating costs for a rotary adsorption/RTO system depend on flow rate, VOC load, and 

desired efficiency. Munters estimated that $2 - $3/cfm would be accurate to use for 

annual operating costs (which includes natural gas and electricity). The following costs 

are not included in the $2-3/cfm estimate: labor, monitoring and recordkeeping, 

maintenance, and insurance costs. Operating and maintenance cost for the booths was 

not included in this analysis. 

C. Annualized Cost Estimates

In order to calculate annualized cost estimates per facility, an airflow of 52,000 cfm was 

used to represent an average spray booth.3

 Operating costs of electricity and natural gas 

(based on $3/cfm estimate provided by Munters) were not annualized. 

Initial Capital Costs – Booth

$140,616 per Booth x 3 Booths = $422,000 

Initial Capital Costs – RTO System (based on Table 1) 

 52,000 cfm x $18/cfm x 3 Booths = $2,808,000 

Additional Capital Costs (for interest, taxes, engineering, and shipping/delivery - based 

on a 25% estimate from the OAQPS cost manual) 

Spray Booths

 $422,000 x 1.25 = $528,000 

RTO System

 $ 2,808,000 x 1.25 = $3,510,000 

Annualized Capital Costs (based on 10 year equipment life and 7% interest rate) 

 ($3,510,000 + $528,000) x 0.1424 = $575,000 

Operating Costs – RTO System

 52,000 cfm x $3/cfm = $156,000 

Total Estimated Annual Costs (Annualized Capital + Operating)

 $575,000 + $156,000 = $731,000 [per facility] 

 

3

 Based on the NASSCO Shipyard’s exhaust airflow of five recently installed spray coating booths. 

3 
D. Estimated amount of VOC/HAP controlled

It was assumed that 25% of total coating operations at a facility would occur in spray 

booths and that each booth has a capture efficiency of 90 percent. 4

 The control 

efficiency for the adsorption/RTO system used was 95%. Since spray booth coating 

can only be performed at shipyards that operate modular indoor coating, it was 

estimated that 20 facilities of the 85 included in risk analysis modeling would incur 

these costs. Using the estimated total HAP emitted from 20 shipbuilding facilities, 

224 tpy, the amount of VOHAP controlled industry wide would be5

: 

Amount of VOHAP captured and controlled

224 tpy x 0.25 (estimated % of coating that would occur in booths) x 0.90 Capture 

Efficiency x 0.95 Control Efficiency = 48 tpy

E. Estimated Cost Effectiveness of Booth equipped with a RTO system

Based on the annualized cost estimate and the estimated amount of HAP controlled, the 

cost effectiveness of the ship enclosure was calculated. 

Cost effectiveness for spray booths equipped with RTO system

Cost Effectiveness = Total Annual Costs/Annual HAP controlled 

Cost Effectiveness = $731,000 per facility x 20 Facilities / 48 tons = 

$305,000/ ton of HAP reduced

II. ENCLOSURE FOR SHIPSIDE COATING 

A second, more theoretical, cost analysis was also performed for controlling shipside 

emissions using a large painting and blasting enclosure around an entire ship. As 

previously mentioned shipside emissions usually occur during ship repair operations and 

new ship construction once the ship has been assembled. The number of docks a 

shipyard contains varies; it was assumed that an average shipyard contains four docks 

that would be enclosed. The cost estimate was based on capital cost quotes from Munters 

and Kelly Klosure, a manufacturer of pre-framed, modular, and temporary steel 

structures. 

A. Capital Costs 

 

4

 Based on NASSCO estimates that 25% of coating occurs in booths. 

5

 224 tpy based on HAP coating operation emissions of 85 facilities modeled for the Shipbuilding and Ship Repair 

risk analysis 950 tpy x (20/85). 

4 
In order to calculate capital costs for a structure that encloses a typical size ship, Kelly 

Klosure was contacted for a commercial quote based on a 54 ft wide x 99 ft long x 22 ft 

tall painting and blasting enclosure (provided in Attachment 2). This cost was scaled up 

to a structure with 70 ft wide x 800 ft long x 100 ft tall dimensions that could enclose a 

large ship (or portion of a large ship) and was estimated to be $5.4 million dollars. 

Similar to the spray booth controls discussed previously, the capital costs of a rotary 

adsorption/RTO system includes capital cost for the concentrator, filters, process fan, 

controls, integrated desorption heater, integrated RTO, and startup services, and is based 

on an skid mounted systems for easy installation. The cost analysis for the rotary 

adsorption/RTO system was based on Munter’s costs in Table 1 and an estimated 

250,000 cfm exhaust airflow from the enclosure. Additional capital costs to account for 

interest, taxes, and engineering were based on a 25 percent estimate from the OAQPS 

cost manual were added to the capital costs of the enclosure and the RTO system. 

B. Operating Costs

As previously mentioned, no operating and maintenance costs were included for the 

enclosure. Similar to the booths, the operating costs for the RTO system depend on flow 

rate, VOC load, and desired efficiency. The $2 - $3/cfm estimate was used to calculate 

O&M costs for the rotary adsorption/RTO system. This cost includes natural gas and 

electricity, but does not include labor, monitoring and recordkeeping, maintenance, and 

insurance costs. 

C. Annualized Cost Estimates

The capital costs of the enclosure and the rotary adsorption/RTO system were annualized 

based on a 10 year equipment lifetime and a 7.0 percent interest rate. Operating and 

maintenance costs were not annualized. 

Enclosure 

Capital Cost of One Enclosure: $5.4 Million 

Additional Capital Costs of Enclosure (for interest, taxes, and engineering - based on 

a 25% estimate) 

 $5,400,000 x 0.25 = $1,350,000 

Annualized Capital Costs (based on 10 year equipment life and 7% interest rate) 

($1,350,000 + $5,400,000) x 0.1424 = $961,000 

Total Estimated Annual Costs of Enclosure (Annualized Capital + Operating)

5 
$961,000 + $0 O&M Cost = $961,000 per year 

Rotary Adsorption/RTO System 

Capital Cost of RTO (based on Table 1) 

250,000 cfm x $13/cfm = $3,250,000 

Additional Capital Costs for RTO (for interest, taxes, engineering, and 

shipping/delivery - based on a 25% estimate from cost manual) 

$3,250,000 x 0.25 = $813,000 

Annualized Capital Costs of RTO (based on 10 year equipment life and 7% 

interest rate) 

($3,250,000 + $813,000) x 0.1424 = $579,000 

Operating Costs

250,000 cfm x $3/cfm = $750,000 

Total Estimated Annual Costs of RTO (Annualized Capital + Operating)

$579,000 + $750,000 = $1,329,000 per year 

Total Estimated Annual Costs of RTO + Enclosure

$1,329,000 + $961,000 = $2,290,000 per shipside coating location 

Since most major source shipyards have multiple locations where shipside coating 

occurs, we estimated that an average shipyard will have 4 locations (e.g., drydocks, 

graving docks, marine railways) where such painting operations are conducted. 

Therefore, the average facility costs are: 

$2,290,000 per location x 4 locations (docks) = $9,160,000 per facility 

D. Estimated amount of VOC/HAP controlled

The enclosure quoted by Kelly Klosures contains one removable end wall but can be 

entirely closed. It was assumed that the enclosure would capture 90 percent of the 

volatile organic emissions from coating operations performed inside the structure. In 

order to estimate the amount of painting and solvent use that occurs shipside, estimates 

from the NASSCO facility were used and are summarized in Table 2. A 95 percent 

control efficiency for the adsorption/RTO system was used. 

6 
Table 2. Percentage of coating operations that occurs shipside.6

Type of Coating 

Operation 

Percentage that 

Occurs Shipside 

Painting 56.5 

Solvents 56.5 

Penetrating Dyes 32.4 

Average of all coating 

operations 

49 

 

Using the total HAP emitted from shipbuilding facilities subject to Subpart II (950 tpy) 

and the estimated 90 percent enclosure (capture) and 95 percent control (destruction) 

efficiency, the amount of VOHAP controlled industry wide would be7: 

Amount of VOHAP captured and controlled

950 tpy x 0.49 (% of coating that occurs Shipside) x 0.90 Capture Efficiency 

x 0.95 Control Efficiency = 398 tpy 

E. Estimated Cost Effectiveness of Enclosure and RTO system

Based on the annualized cost estimate and the estimated amount of HAP controlled the 

cost effectiveness of the ship enclosure was calculated. 

Cost effectiveness for shipside coating enclosure

Cost Effectiveness = Annualized Costs/Annual HAP controlled 

Cost Effectiveness = $9,160,000 per facility x 85 facilities / 398 tons = 

$1,956,000/ton of HAP controlled

 

6

 Based on 1993 AB 2588 Health Risk Assesment – NASSCO. January 1997. 

7

 HAP coating operation emissions of 85 facilities modeled for the Shipbuilding and Ship Repair risk analysis. 

7 
Attachment 1. 

Booth Quote 

8 
Email from Munters containing Cost Estimate Information and NASSCO 

----- Original Message ----- 

From: <Cheryl.Thibault@munters.com> 

To: "Mary-Jo Caldwell" <mjcaldwell@nc.rr.com> 

Sent: Thursday, June 10, 2010 4:39 PM 

Subject: Re: Costing rules of thumb 

> Hello Mary-Jo, 

> 

> Munters Zeol Rotor Concentrators are best suited for high volume/low 

> concentration applications. Our technical rules of thumb for determining 

> if a particular application is a good one are as follows: 

> 

> 1) Inlet temperature should be less than 100 degrees F. 

> 2) Inlet relative humidity should be less than 90% 

> 3) Inlet VOC concentration should be less than 500 ppm. (This does depend 

> on the types of VOCs so certain VOCs may have a lower limit.) 

> 4) VOCs should have boiling points above ambient temperature. Any low 

> boiling compounds or gases at ambient temperature will not adsorb well. 

> 

> For scope, we would propose a zeolite rotor concentrator integrated with an 

> RTO for larger ship building/spray painting applications. We used to use 

> catalytic oxidizers but have found that paint formulations are constantly 

> changing and some VOCs can harm and poison catalyst. An RTO is much more 

> fuel efficient that a catalytic oxidizer and comparable in price anyway. 

> They eliminate the need for replacement catalyst. Our systems can be 

> designed to meet whatever destruction efficiency is required up to about 

> 99%. Typically, customers are required to meet 95% system efficiency. The 

> higher the DRE, the more expensive the system gets. The lower the DRE, the 

> smaller the rotor we can use and the smaller the oxidizer for a much more 

> cost-effective system. 

> 

> In terms of budget costing, you could use a $/cfm but as you may expected 

> smaller systems will have a larger $/cfm because much of the cost 

> (engineering design, controls, instrumentation, startup labor) are the same 

> regardless of the size of the system. So budget pricing would be $30/cfm 

> for flows less than 10,000 cfm, $25/cfm for flows 10,000-20,000 cfm, 

> $20/cfm for 20,000 cfm-40,000 cfm, $18/cfm 40,000-60,000 cfm, $15/cfm for 

9 
> 60,000 - 80,000cfm and $13/cfm for > 80,000 cfm. These prices would 

> include concentrator, filters, process fan, controls, integrated desorption 

> heater and integrated RTO and startup services. Munters manufactures 

> systems and factory tests them. As long as they are within shipping size 

> restrictions, they ship as one piece, skid mounted for easy installation. 

> Not included in the pricing would be installation, freight, taxes, 

> compliance testing, etc. Operating costs are more specific to the 

> project depending on flow rate, VOC load and desired efficiency. I think 

> it would be safe to use $2 - $3/cfm for annual operating costs (natural gas 

> & electricity). See tables below for example operating costs for a 80,000 

> cfm system and a 40,000 cfm system. I also provided comparison tables for 

> an 80,000 cfm straight RTO and 40,000 cfm RTO. Munters concentrator system 

> saves the company about $300,000 per year in operating costs based on 

> 80,000 cfm. 

> 

> As for Northrup in MS, we don't feel comfortable giving out details on VOC 

> loading and booth type. The sales person involved with this project is no 

> longer with us so we don't have details on spray booth type. I would 

> encourage you to go direct to the customer. 

> 

> However, I will say that we have supplied concentrator/oxidizer abatement 

> system for lots of different types of painting applications including spray 

> painting with manual spray and automatic spray, with dry particulate 

> filtration and with water wash filtration systems. We like to treat oven 

> exhaust direct in the oxidizer rather than combine it with booth exhaust 

> through the concentrator. Typical inlet VOC concentrations are 30-150 ppm. 

> Typical VOCs are butanol, isopropanol, ethyl acetate, butyl acetate, 

> xylene, toluene, naptha, MEK, MIBK, acetone, ethyl benzene, trimethyl 

> benzene, PGMEA, propanol. Many times, there are multiple booths tied to 

> one abatement system with different flow conditions (ie, one booth on, two 

> booths on, etc.) We can operate the concentrators at different flow 

> conditions (i.e., 25,000 cfm from one booth or 50,000 cfm from two booths). 

> 

> I hope this helps for your analysis. If you need anything further, let me 

> know. 

> 

> Regards, 

> Cheryl Thibault 

> Munters Corporation 

> 79 Monroe St. Amesbury, MA 01913 

10 
> work 978-241-1163 

> cell 978-660-3243 

> 

> 

> Munters Rotor Concentrator | No VOC | 50% VOC | 100% VOC 

> System - treating 80,000 | | 21 lbs/hr | 42 lbs/hr 

> cfm | | | 

> -------------------------------+--------------+-------------+-------------- 

> Fuel Use (mmBtu/hr) | 1.70 | 1.41 | 1.36 

> -------------------------------+--------------+-------------+-------------- 

> Fuel Cost (per hour) | $17.04 | $14.07 | $13.65 

> -------------------------------+--------------+-------------+-------------- 

> Fuel Cost (annual) | $68,161 | $56,291 | $54,609 

> -------------------------------+--------------+-------------+-------------- 

> | | | 

> -------------------------------+--------------+-------------+-------------- 

> Electricity Use (kW) | 193 | 193 | 193 

> -------------------------------+--------------+-------------+-------------- 

> Electricity Cost (per hour) | $19.27 | $19.27 | $19.27 

> -------------------------------+--------------+-------------+-------------- 

> Electricity Cost (annual) | $77,077 | $77,077 | $77,077 

> -------------------------------+--------------+-------------+-------------- 

> | | | 

> Total (per hour) | $36.31 | $33.34 | $32.92 

> (annual) | $145,238 | $133,368 | $131,686 

> 

> 

> 

> 

> Munters Rotor Concentrator | No VOC | 50% VOC | 100% VOC 

> System - treating 40,000 | | 10.5 | 21 lbs/hr 

> cfm | | lbs/hr | 

> --------------------------------+--------------+------------+-------------- 

> Fuel Use (mmBtu/hr) | 0.85 | 0.70 | 0.68 

> --------------------------------+--------------+------------+-------------- 

> Fuel Cost (per hour) | $8.52 | $7.04 | $6.83 

> --------------------------------+--------------+------------+-------------- 

> Fuel Cost (annual) | $34,080 | $28,146 | $27,304 

> --------------------------------+--------------+------------+-------------- 

> | | | 

11 
> --------------------------------+--------------+------------+-------------- 

> Electricity Use (kW) | 96 | 96 | 96 

> --------------------------------+--------------+------------+-------------- 

> Electricity Cost (per hour) | $9.63 | $9.63 | $9.63 

> --------------------------------+--------------+------------+-------------- 

> Electricity Cost (annual) | $38,538 | $38,538 | $38,538 

> --------------------------------+--------------+------------+-------------- 

> | | | 

> Total (per hour) | $18.15 | $16.67 | $16.46 

> (annual) | $72,618 | $66,684 | $62,842 

> 

> 

> 

> 

> Straight | No VOC | 50% VOC | 100% VOC 

> RTO | | 21 lbs/hr | 42 lbs/hr 

> treating | | | 

> 80,000 cfm | | | 

> -------------------------------+-----------------+------------+-------------- 

> Fuel Use (mmBtu/hr) | 8.79 | 8.49 | 8.20 

> -------------------------------+-----------------+------------+-------------- 

> Fuel Cost (per hour) | $87.92 | $84.90 | $82.00 

> -------------------------------+-----------------+------------+-------------- 

> Fuel Cost (annual) | $351,680 | $339,600 | $328,000 

> -------------------------------+-----------------+------------+-------------- 

> | | | 

> -------------------------------+-----------------+------------+-------------- 

> Electricity Use (kW) | 273 | 273 | 273 

> -------------------------------+-----------------+------------+-------------- 

> Electricity Cost (per hour) | $27.27 | $27.27 | $27.27 

> -------------------------------+-----------------+------------+-------------- 

> Electricity Cost (annual) | $109,000 | $109,000 | $109,000 

> -------------------------------+-----------------+------------+-------------- 

> | | | 

> Total (per hour) | $115.19 | $112.17 | $109.27 

> (annual) | $460,760 | $448,680 | $437,080 

> 

> 

> 

> 

12 
> Straight | No VOC | 50% VOC | 100% VOC 

> RTO | | 10.5 | 21 lbs/hr 

> treating | | lbs/hr | 

> 40,000 cfm | | | 

> | | | 

> -------------------------------+-----------------+------------+------------- 

> Fuel Use (mmBtu/hr) | 4.39 | 4.25 | 4.1 

> -------------------------------+-----------------+------------+------------- 

> Fuel Cost (per hour) | $43.90 | $42.50 | $41.00 

> -------------------------------+-----------------+------------+------------- 

> Fuel Cost (annual) | $175,600 | $170,000 | $164,000 

> -------------------------------+-----------------+------------+------------- 

> | | | 

> -------------------------------+-----------------+------------+------------- 

> Electricity Use (kW) | 136 | 136 | 136 

> -------------------------------+-----------------+------------+------------- 

> Electricity Cost (per hour) | $13.60 | $13.60 | $13.60 

> -------------------------------+-----------------+------------+------------- 

> Electricity Cost (annual) | $54,400 | $54,400 | $54,400 

> -------------------------------+-----------------+------------+------------- 

> | | | 

> Total (per hour) | $57.50 | $56.10 | $54.60 

> (annual) | $230,000 | $224,400 | $218,400 

> 

> 

> 

> 

> Based on $10.00 per MM Btu, $0.10 per kW, 4,000 hours/year 

13 
CORRESPONDENCE WITH AGENCIES AND INDUSTRY

Date: 5/11/10 

Person Calling: Art Gonzalez 

Source Name: San Diego County APCD 

City, State, County: San Diego, CA 

NEI Number: N/A 

State #: N/A 

Dept/Phone Number: 858-586-2721; art.gonzalez@sdcounty.ca.gov 

Mr. Gonzalez was listed as the agency contact for a project that involved the 

installation of concentrator/regenerative thermal oxidizers on spray booths at the 

NAASCO facility in San Diego County. I contacted Mr. Gonzalez to find out if the 

permitted add on control units were ever installed and if so, to learn more about 

the installation. 

Mr. Gonzalez said that the five concentrator/regenerative thermal oxidizers were 

installed on five spray booths last summer. He said he thought they had been 

installed last August, and would confirm the installation date in a subsequent email 

to me. He said so far the units have been operating as designed, as far as he 

knows. He’s not aware of any problems. The facility originally considered 

modifying existing permits to allow installation of the spray booths, but due to 

concerns about emission caps, decided to get new permits for the spray booths. 

Because offsets are complex and expensive, the facility decided to install add-on 

controls to control HAP emissions from coating operations. 

14 
Mr. Gonzalez is going to email me the data sheets for the installation. He 

indicated the units are manufactured by Triton. The coating booths, or cells, are 

quite large. Four of the paint spray booths, or cells are approximately 

100’x80’x65’; and one is slightly smaller. The airflow from each of the spray 

booths is approximately 52,000 cfm. Mr. Gonzalez said he thought his file 

contained information regarding the VOC/HAP concentration into the 

concentrator, and would include that information in his email to me. He said 

primers and topcoats are sprayed in the booths, and that he would include more 

specifics regarding the types of paints as available, in his email. 

I asked Mr. Gonzalez if he knew of any installations at shipyards that use add-on 

controls to control HAP emissions from shipside painting operations (i.e., painting 

of assembled ship, outside of any spray booth or cell). He said he was not aware of 

any such installations. I asked him if he knew of any add-on controls being used to 

control abrasive blasting or welding emissions from shipside blasting or welding. 

He said that was not his area, and promised to provide the contact information for 

the San Diego APCD person to ask. 

15 
Attachment 2. Kelly Klosure Quote 

16 
17