An off-spec fuel: Can your boilers burn it economically

Journal Article · Sat Mar 01 04:00:00 EST 1986 · Power; (United States)

OSTI ID:5757661

Moore, G F

An off-spec fuel is one that has different characteristics from the fuel for which the boiler was designed. A change in fuel can impair both the boiler and its availability, but the reasons for change are many. Perhaps the design fuel is no longer available. Environmental factors impel change, too. For example, choosing a low-sulfur fuel may avoid a scrubber installation. There are often problems accompanying fuel change, however, Examples: Several utilities in central Illinois and western Kentucky have had to build coal-cleaning plants because coal ash content has increased, causing unscheduled outages and maintenance problems. Midwestern utilities that decided to burn high-moisture subbituminous western coals ran into problems. The coal - with high heating value of 8000-9500 Btu/lb, 20-30% moisture, and 5-10% ash, burned in a boiler designed for eastern or midwestern bituminous coal - forced derating because of lack of pulverizer capacity. Further derating resulted from high temperature in the convection pass, from high moisture level in the coal. An Ohio River plant had a reheater plug solid in less than a day, when a Montana subbituminous coal was under test. Some western coals have more sodium than eastern and midwestern coals, also lower ash fusion temperatures. The two factors can cause fouling and slagging. Several East Coast utilities with Cyclone furnaces encountered a problem, too. They require coal with low ash fusion temperature, and this created the need for additives when burning high-fusion, low-sulfur coal to satisfy air-pollution regulations or for installation of flue-gas scrubbers.

• Research Organization: Stone and Webster Engineering Corp.
• OSTI ID: 5757661
• Journal Information: Power; (United States), Journal Name: Power; (United States) Vol. 130:3; ISSN POWEA
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
014000* -- Coal
Lignite
& Peat-- Combustion
02 PETROLEUM
025000 -- Petroleum-- Combustion
42 ENGINEERING
421000 -- Engineering-- Combustion Systems
ADDITIVES
ASHES
BOILER FUELS
BOILERS
CARBONACEOUS MATERIALS
CHEMICAL REACTIONS
COAL
COMBUSTION
ELECTRIC UTILITIES
ENERGY SOURCES
FOSSIL FUELS
FOULING
FUEL OILS
FUEL SUBSTITUTION
FUELS
FURNACES
LIQUID FUELS
MATERIALS
MELTING
OILS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
OXIDATION
PETROLEUM PRODUCTS
PHASE TRANSFORMATIONS
PUBLIC UTILITIES
RESIDUES
SULFUR CONTENT
THERMOCHEMICAL PROCESSES