Combustion characterization of the Kentucky No. 9 cleaned coals: Final report

Technical Report · Sun Feb 01 04:00:00 EST 1987

OSTI ID:6829798

Chow, O K; Lexa, G F

A comprehensive research program was conducted to assess the merits of coal cleaning as a means of improving utility boiler operation. This program involved detailed bench and pilot scale assessment of pulverization, combustion, furnace slagging, convective pass fouling, emissions and fly ash erosion characteristics of a Kentucky No. 9 baseline coal and its medium cleaned and deep cleaned products. Test results were applied, using Combustion Engineering's (C-E) in-house computer models, to predict the performance of a 350 MW utility boiler and its auxiliary equipment using the cleaned coals. Results indicated that cleaning had a beneficial effect on nearly all areas of fuel performance. The reduction in ash quantity due to cleaning significantly improved pulverization in terms of grinding energy requirement and reduction in fuel abrasion/mill wear. Fly ash erosion decreased significantly with increased cleaning at equivalent operating conditions which could result in longer convection tube life. The lower sulfur content of the cleaned coals reduced sulfur dioxide emission control requirement. Furnace slagging characteristics showed improvement for the cleaned coals. Waterwall deposits developed from each coal were thin and molten. The critical pilot-scale test conditions for cleanable deposits were at a 3.2 MBtu/hr fuel firing rate and a flame temperature of 2810/sup 0/F for the baseline coal. These critical conditions increased to a firing rate of 3.4 MBtu/hr and a flame temperature of 2830/sup 0/F for the cleaned coals, indicating a potential for operating at higher loads in a commercial furnace. Fouling characteristics also improved with increased coal cleaning. The lower ash loading of the cleaned coals decreased ash deposition rates, resulting in lower soot blowing requirements.

• Research Organization: Combustion Engineering, Inc., Windsor, CT (USA). Power Systems Group; Electric Power Research Inst., Palo Alto, CA (USA)
• OSTI ID: 6829798
• Report Number(s): EPRI-CS-4994; ON: TI87920272
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010300* -- Coal
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& Peat-- Preparation-- (1987-)
010600 -- Coal
Lignite
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20 FOSSIL-FUELED POWER PLANTS
200108 -- Fossil-Fueled Power Plants-- Fuels-- (1980-)
AEROSOL WASTES
AIR POLLUTION CONTROL
ASHES
BENCH-SCALE EXPERIMENTS
BOILERS
CARBONACEOUS MATERIALS
CLEANING
COAL
COAL PREPARATION
COMBUSTION PROPERTIES
CONTROL
COST BENEFIT ANALYSIS
DEPOSITION
DEPOSITS
ENERGY CONSUMPTION
ENERGY SOURCES
EROSION
FLY ASH
FOSSIL FUELS
FOSSIL-FUEL POWER PLANTS
FOULING
FUELS
GRINDING MACHINES
MACHINE TOOLS
MATERIALS
POLLUTION CONTROL
POWER PLANTS
RESIDUES
SLAGS
SULFUR CONTENT
TEST FACILITIES
THERMAL POWER PLANTS
TOOLS
WASTES
WEAR