P.1 

OAR Box 1865 

Prepped by Charmelle Mathews 

Document Number: 

95) IV-J-38 

Docket Number: 

A-83-27 

Printed 12/3/2008 9:15:32 AM Sheet 95 of 105 
-E-2- . 

DORR OLIUER 

A-'83-27 

IV-J-38 

Case History

 # 3 

Quaker State Oil Switches to Coal 

for Steam Generation 

Conversion is First Large 

Privately Funded Coal 

Burning Fluid Bed Boiler 

Project in U.S.A. 

Quaker State's Congo Refinery in Newell, West Virginia has 

converted to coal-fired boilers 

designed and fabricated by Keeler/ 

Dorr-Oliver. Congo was the only 

one of three Quaker State refineries in the Perm Grade Crude 

Region to not utilize coal as its 

primary fuel for steam generation. 

Constructed in 1972, Congo 

used No. 6 residual fuel oil as its 

primary fuel for process heaters 

and steam generation. Lower 

capital equipment investment of 

package boilers and fuel handling 

systems of residual fuel made 

coal-fired units unattractive for 

the refinery at that time. Environmental regulations were also 

inexpensively and easily satisfied 

by restricting residual fuel to a 

maximum of 2.0% sulfur. 

Quaker State decided to 

research coal-fired steam generators for its Congo Plant after 

analyzing the escalation of residual fuel costs. Prices increased 

sharply due to OPEC crude oil 

price increases and strict environmental regulations on new 

and modified emission sources 

imposed by the 1977 Amendment 

to the Clean Air Act From 1972 to 

1982, the cost of residual fuel 

increased 600% - from $4.00 per 

barrel ($.56 per MM BTU) to 

$26.50 per barrel ($3.61 per MM 

BTU). During the same period, 

coal costs at the other two Quaker 

State refineries increased only 

270% - from $10.00 per ton ($.42 

per MM BTU) to $27.00 per ton 

($1.15 per MM BTU). Based on 

Two Quldlzed bed coal-fired boilers at Quaker State's Congo Refinery. 

fuel costs alone, a potential $4.5 

million per year could be saved by 

converting to coal-fired boilers. 

With this in mind, and with the 

expectation that supply-limited 

oil would continue to escalate in 

price faster than demand-limited 

coal. Quaker State began researching coal-fired boilers for its 

Congo Refinery. 

In 1982, at the recommendation of Stanley Jones Mechanical Contractors, Inc, Keeler/DorrOliver was selected to design, 

fabricate and erect two fluidized 

bed coal-fired boilers. Each ofthe 

two Keeler/Dorr-Oliver boilers 

have the capacity to generate 

120,000 pounds of superheated 

steam per hour (54.480 kg/hr) at 

265 psig (120 kg) pressure with 

100°F (56°C) superheat The 

scheduled completion date is 

May. 1985. 
Economics Environmental 

Considerations 

Quaker State decided to install fluidized bed boilers rather 

than conventional boilers after 

analyzing many economic and 

environmental factors. The economic review analyzed the payback of a conventional boiler plant 

and wet scrubbers or compliance 

coal vs. a fluidized bed boiler 

installation. 

The conventional boiler plant 

and baghouse installation cost 

was $9 million. For environmental 

reasons, the plant would require 

low sulfur compliance grade coal 

at a cost of $55 per ton. Annual 

fuel savings was estimated at 

$3,568,500. Additional ash disposal costs adjusted the fuel 

savings to $3,472,000. This installation provided a simple payback of 2.59 years. 

The fluidized bed boiler 

installation cost $13,500,000. 

Suitable coal cost $35.00 a ton. 

Annual fuel savings was projected 

to be $5,121,000. This was adjusted to $4,164,000 after including annual limestone cost of 

$482,000 and ash disposal cost 

at a conservative $10.00 a ton. 

The simple payback is 3.24 years 

and could be less if a lower sulfur 

content coal is burned. Both 

installations were eligible for a 

10% energy tax credit and an 

investment tax credit 

Further analysis of the two 

installations showed that availability and pricing was not 

assured for low-sulfur compliance grade coal, needed for a 

conventional boiler plant Therefore, flue gas desulfurization 

equipment would most likely 

need to be installed if a conventional boiler plant was built This 

equipment alone would require 

about the same capital investment 

as the fluid bed generators. With 

these and several environmental 

considerations in mind, Quaker 

State decided to install fluid bed 

steam generators. 

Conventional vs. Fluidized Bed Boiler Installation 

Equipment 

Sulfur Content 

Cost 

Annual Fuel Savings 

Annual Ash Disposal 

Costs 

Annual Limestone 

Costs 

Adjusted Savings/Year 

Simple Pay Back 

Conventional Boiler Plant 

(•1) without Fine Gas 

DesnUnrimation 

120.000 PPH Stoker boilers 

with baghouse, etc 

1.33% 

$9,000,000 (S75/pph) 

$3,568,500 

$ 96.500 

$3,472,000 

2.59 Years 

Fluid Bed Boiler Plant (*3) 

120.000 PPH AFB boilers 

with baghouse, etc 

4% 

$13,500,000 ($110/pph) 

$ 5,121.000 

$ 475.000 

$ 482,000 

$ 4.164.000 

3.24 Years 

(1) Conventional steam generator plant 

based on annual coal usage of 77.625 

tons at $55.00 per ton plus $ 10.00 per 

ton ash disposal for 12% ash. 

(2) Fluid bed steam generator based on 

annual coal usage of 77.625 tons at 

$35.00 per ton. 4% S coal requiring 0.5 

pound limestone per pound coal and 

$10.00 per ton for 12% ash plus 

limestone disposal. 

Annual fuel savings of the fluidized bed 

boilers was projected at S4.164.000. 

The Congo Plant Is located in 

an area designated by the West 

Virginia Air Pollution Control 

Commission (WVAPCC) as 1) 

Priority Classification I and 2) a 

non-attainment area for meeting 

the National Ambient Air Quality 

Standards for suspended particulates and sulfur dioxide. Due to 

this, the Congo Refinery has 

strict emission limitations for 

construction of coal-fired boilers. 

Quaker State applied to the 

WVAPCC in late 1981 for a permit 

to construct three 120.000 pph 

stoker boilers with a baghouse 

and a related coal and ash 

handling system. The WVAPCC 

Indicated the permit application 

could be approved with Quaker 

State's commitment that the 

sulfur content of coal purchased 

would not exceed 1.33% and the 

annual coal usage would not 

exceed 77.625 tons. Coal suppliers however, expressed thatl 

the coal required to meet the 

emission limitations was too 

restrictive to provide a viable 

supply. This concern, combined 

with the high cost of the 

compliance coal, motivated Quaker State in 1982 to explore the use 

of fluid bed steam generators to 

achieve SOa compliance. 

After discussions with Keeler/ 

Dorr-Oliver, Quaker State decided to run pilot plant studies 

to determine limestone suitability to achieve emission limitations. These studies showed 

that the limestone Quaker State 

proposed to use maintained the 

SO2 emissions below the maximum allowable 1.2 pounds SO2 

per MM BTU for coals containing 

up to 4% sulfur. 

In October, 1983, the West 

Virginia Air Pollution Control 

Commission granted a construction permit reflecting the following conditions: 
P.4 

The 

Contractors 

(1) The concentration of particulate matter admitted from the 

boilers will not exceed 0.03 

grains per dry standard cubic 

foot. SO2 emission rates from 

the boilers will not exceed 1.2 

pounds/MM BTU. 

(2) Steam plant emission limitations (tons/year from stack): 

Particulate Matter 85.6 

(Boiler stack emissions) 

Sulfur Dioxide 1680.0 

Nitrogen Oxides 582.0 

Carbon Monoxide 116.4 

Hydrocarbons 38.8 

(3) Maximum sulfur content of 

coal used will not exceed 4%. 

(4) The sulfur dioxide control 

system will have a minimum 

control efficiency of 82%. 

(5) No more than two of the coal 

and oil-fired boilers will operate at any given time except 

during unit changeovers (startups). 

(6) Annual coal usage will be no 

more than 77.625 tons. 

Review of Past Vs. Allowable Emission Limits 

Prior 

BmJaalons 

(Tons/Year) 

Particulates 143.07 

Sulfur Dioxide 1.953.30 

Nitrogen Oxides 575.77 

Carbon Monoxide 31.10 

Hydrocarbons 6.22 

Allowable Future 

Emissions 

(Tons/Year) 

85.58 

1.944.50 

582.20 

116.43 

38.80 

Net Emission 

Change 

(Tons/Tear) 

-57.5 

- 8.8 

+ 6.43 

+85.3 

+32.6 

EPA Significant 

Increase 

(Tons/Tear) 

25 

40 

40 

100 

40 

• • 

there is not a significant emission increase for any of the above 

emissions. Emission factors are 

based on AP-42 for 2% sulfur No. 6 

fuel oil and stoker-fired steam 

generators. 

Prior emissions are based on 

a 1980-81 average of 12,441.114 

gallons of No. 6 residual fuel with 

heat input of 1.9018 x IO12 BTU 

per year. Equivalent heat input 

from 12.250 BTU per pound coal 

required 77.625 tons of coal 

annually, and required a 67% 

conversion of SO2 to CaS04 with 

4% sulfur coal or a maximum of 

133% sulfur coal with no conversion. Actual SO2 emission of 

82% capture will be about 1,120 

tons/year. 

Quaker State will achieve SOj compliance 

with its new coal-fired boilers. 

Design and Construction 

Contract- Stanley Jones Mechanical Contractors, Inc., South 

Fulton, Tennessee. 

Design, Fabrication and Erection Contract: Keeler/Dorr-Oliver 

Boiler Company, Williamsport, 

Pennsylvania. 

Engineering Contract: I.C. 

Thomasson Associates. Nashville. Tennessee. 

Powerhouse Construction 

Contract: H. & M. Construction, 

Milan, Tennessee. 

^fp^ 

Boiler tubes were shipped for field erection. 

The field-erected CPFS design was utilized by 

Quaker State to produce 120.000 pph. 

A view of the first large privately funded coal 

burning fluidized bed boiler in the U.S. 
The K/D-O Model CPFS 

Steam Generator 

P.5 

Quaker State's two coal-fired 

fluidized bed boilers are Keeler/ 

Dorr-Oliver's model CPFS steam 

generators. The CPFS model can 

be shop fabricated and shipped 

in two modules to generate a 

maximum of 80.000 pounds of 

steam per hour (pph). The Congo 

Refinery required the capacity to 

produce 120.000 pph; therefore, 

the field-erected CPFS design 

was utilized. 

This CPFS design uses a 

sparge pipe air distributor system 

which eliminates the need for 

bed or windbox segmentation. It 

is used to achieve rapid load 

response and high turndown 

capability of 7:1. It also has the 

following advantages: 

1) Permits a completely sealwelded, watercooled floor without numerous penetrations 

from the admission of fluidizing air. 

2) Permits multiple zones without a cumbersome windbox 

design with multiple air supplies and dampers. 

3) Reduces head room by eliminating the windbox under the 

bed. 

4) Eliminates sealing requirement between the windbox 

and fluid bed. 

5) Provides for ease of inspection 

or maintenance (sparge pipe 

can be withdrawn). 

6) Eliminates segregation of large 

ash particles by withdrawing 

bottom ash between sparge 

pipes. 

Individual alloy sparge pipes 

are inserted through the watercooled frontwall and are bolted 

into place. This allows the pipe to 

This CPFS design has die turndown 

capability of 7:1. 

be removed during a boiler outage. Each sparge pipe is equipped 

with a quick acting damper for 

control and a manually operated 

balancing damper. All sparge 

pipes are connected to a common 

air header which receives combustion air from the forced draft 

fan. 

In addition to multiple sparge 

pipes, turndown capability is 

complemented by the placement 

of the in-bed surface along each 

side ofthe furnace. As individual 

sparge pipes are turned off from 

the sides toward the center, a 

disproportionate amount of inbed surface is removed from the 

active bed area which permits a 

further reduction in the fuel feed 

and steam generation per unit of 

plant area. This placement of the 

in-bed surface also provides a 

center firing isle for overbed 

feeding of coal and limestone. 

To prevent erosion problems 

caused by impingement in-bed. 

waterwall and convection tubes 

were placed vertically. Vertical 

tubes were also used because 

horizontal and sloped tubes have 

the tendancy to affect the horizontal bed motion and its influence on functional performance 

is not always predictable. 

The boilers are ofthe natural 

circulation type which are known 

for their simplified operation and 

maintenance and their lower 

capital and operating costs. 

Keeler/Dorr-Oliver also supplied 

a superheater and economizer 

for the bubbling bed combustion 

system. The system delivers 

120,000 pph (54,480 kg/hr) of 

265 psig (120 kg) superheated 

steam with 100°F (56°C) superheat An alrheater was not 

necessary for this installation. 

The specified coal size is 1 lA" 

x 0. Fuel is injected into the 

furnace over the bed by a 

spreader stoker. Steam production is then controlled by adjusting the fluidizlng-air velocity and 

adjusting the fuel flow. 

The spreader stoker also 

injects sorbent into the combustion zone at one point from over 

the bed. The sorbent particulate 

size specified is W x 0 for 

optimum SO2 control. A fabric 

filter controls particulate emission, and an internal recycle loop 

is used to improve carbon 

burnout and reduce sorbent 

consumption. 

Steam generation 

Steam conditions 

Turndown 

Pud 

SOa Capture 

2 x 120.000 pph MCR 

265 psig with 100°F 

superheat or 510°F 

7:1 

Bituminous coaL 4% 

S.HV 12500 BTU/lb. 

ash 12% 

82% 

t 

DORROLIUER 

P.O. Box 548 • WUliamsport. PA 17703 • (717) 326-3361 

Bulletin No. K/D-O 44C185