p.1 

OAR Box 1168 

Prepped by Ollie Stewart 

Document Number: 

70) lll-B-5 

Docket Number: 

A-89-10 

Printed 4/29/2008 11:23:19 AM Sheet 70 of 131 
P.2 

A-89-10 

II-B-5 

MEMORANDUM 

TO: Bob Ajax, EPA/SDB 

FROM: Ed Moretti, Radian/RTP 

DATE: March 20, 1990 

SUBJECT: Costs of Single and Double Mechanical Seals for Pumps 

§ ii 

I 4-199! 

EPA AIR DOCKET 

The installed cost to retrofit a single mechanical seal with a double 

mechanical seal is estimated to be $1,460, including installation costs of 

$440. The cost for a new double mechanical seal is estimated to be $830 

when installed instead of a new single mechanical seal. A credit of $560 

for a new single mechanical seal was subtracted from the double seal cost of 

$1,020 to yield a net double seal cost of $460. Labor to install the new 

double mechanical seal in a shop area was estimated as $370. Actual costs 

for double mechanical seals will vary greatly, depending on the pump shaft 

diameter, the material of construction of the seal, the pump operating 

pressure and temperature, and the physical and chemical properties of the 

material to be pumped. Auxiliary equipment, such as a cooler for control of 

the temperature of the liquid used to flush the seal may be required, at a 

cost of approximately $1,240; also, an individualized pressurized pot system 

may be required to maintain pressure on the liquid used to flush each double 

seal, at a cost of approximately $300, according to recent vendor 

information. Cost of a closed-vent system is estimated to be $5,190. 

See the enclosures for the sources of the above cost information. 

Additional cost information is expected from two other pump or seal vendors. 

__!___ 
1 

Item 

Single 

Mechanical Seal 

TABLE. 

Cost (1st 

quarter 1990) 

$560 

PUMP SEAL COSTS 

Cost Basis 

Seal Cost based on telephone call 

to seal vendors. 

P.3 

Double . 

Mechanical 

Seal 

$1,460 (retrofitted) Seal Cost = $1,020. (Based on 

telephone call to seal vendors.) 

Field Installation = $440. 

(Updated from NSPS BID using BLS 

Producer Price Index.) 

$830 (new) 

Barrier Fluid 

System for Double 

Mechanical Seals 

$1,540 

Closed-Vent 

System for Double 

Mechanical Seals 

$5,190/pump 

Seal Cost = $1,020. (Based on 

telephone call to seal vendors.) 

Single Seal Credit = $560. 

Shop Installation = $370. (Updated 

from NSPS BID using BLS Producer 

Price Index.) 

Pressurized Reservoir System = 

$300. (Based on telephone call to 

vendors.) 

System Cooler = $1,240. (Updated 

from NSPS BID using CE Plant Cost 

Indices for Pipes, Valves, 

Fittings. 

Based on installation of a 

122 m length of 5.1 cm diam. 

schedule 40 carbon steel pipe 

at a cost of $8,040 (updated from 

NSPS BID using CE Plant Cost 

Indices for Pipes, Valves, 

Fittings), plus three 5.1 cm cast 

steel plug valves and one metal 

gauge flame arrestor at a cost of 

$2,330 (updated from NSPS BID using 

CE Plant Cost Indices for Pipes, 

Valves, Fittings). These costs 

include connection of the degassing 

reservoir to an existing enclosed 

combustion device or vapor recovery 

header. Therefore, cost of a 

control device added specifically 

to control the degassing vents is 

not included. Assumes that two 

pumps are connected to a single 

degassing vent. 
P.4 

TABLE. EQUIPMENT COST FOR CONTROL OF EMISSIONS FROM A PUMP SEAL 

(1989-1990 Dollars) 

Retrofitted New 

Capital Costs 

Dual Seal (Footnotes A,B) 1,460 830 

Barrier Fluid 1,540 1,540 

Vent System 5,190 5,190 

Total 8,190 7,560 

Annual Costs 

660 

250 

850 

160 

330 

330 

250 

850 

160 

300 

Dual Seal (Footnote C) 

Barrier Fluid (Footnote D) 

Vent System (Footnote D) 

Quarterly LDAR (Footnote E) 

Miscellaneous Charges (Footnote F) 

Total (Footnote G) 2,250 1,890 

A. Retrofitted seal costs: Seal cost = $1,020, Field installation cost = 

$440. 

B. New seal costs: Seal cost = $1,020, Shop installation cost = $370, 

Single-seal credit = $560. 

C. Based on 2-year seal life and 10 percent interest (CRF = 0.58) for dual 

seal and 10-year amortization period and 10 percent interest (CRF = 

0.163) for installation charges. 

D. Based on 10-year equipment life and 10 percent interest (CRF = 0.163). 

E. Based on information from a LDAR contractor. 

F. Based on 4 percent of total capital costs (see Page 8-10 of the BID). 

G. Costs do not include credits for recovered product. 
P.5 

TABLE. NET ANNUALIZED COST OF EQUIPMENT FOR CONTROL 

OF EMISSIONS FROM PUMP SEALS 

(1989-1990 Dollars) 

Retrofitted New 

Gross Annualized Cost ($/yr) $2,250 $1,890 

Emission Reduction (Mg/yr) (Footnote A.) 0.41 0.41 

Product Recovery Credit ($/yr) (200) (200) 

(Footnote B.) 

Net Annualized Cost ($/yr) $2,050 $1,690 

A. Average Emission Factor for light liquid pumps = 0.0494 kg/hr/source. 

Assumes 8,760 hours operation per year. 

Assumes 95% reduction in pump seal emissions attributable to dual 

mechanical seal. 

B. Product valued at $480/Mg. Updated from NSPS AID using Bureau of Labor 

Statistics Producer Price Index.