Compact coal combustor with integral dry ash removal. Annual report, October 1, 1983-September 30, 1984

Technical Report · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5913273

Krishna, C R

A promising approach for conversion to coal of existing oil and gas-fired boilers is to retrofit with a combustor that removes most of the ash before the boiler. The present project has resulted in the design and preliminary proof-of-concept testing of such a combustor. The outstanding characteristics of this non-slagging, dry ash removal combustor are listed: (1) Combustion and dry ash removal in one compact unit confines deleterious ash effects (corrosion-erosion) to this stage. (2) Dry ash operation throughout allows use of lower temperature and less costly materials or, with the best available materials, longer life and high reliability. Corrosion by slag, slag tap plugging and the difficulties of handling molten ash are avoided. Low temperature operation is more compatible with pre-cleaned coal water mixture as the fuel. (3) Simple inertial ash separation can be independently controlled to give reliable and effective ash removal even under turndown conditions. (4) The dry ash operation and the independent control of ash separation assures stable and good performance under turndown while the need to maintain a thin mobile slag layer, in the case of the slagging cyclones, would make it sensitive to turndown. (5) Dry ash combustion of moderately loaded CWM's (50% coal) without support fuel and external air preheat has been demonstrated on the test unit. (6) Excellent carbon conversions (greater than 90%) have been attained over a wide range of thermal inputs, combustion intensities and air-fuel ratios. (7) The potential for dry ash removal has been shown with removal efficiencies greater than 60% overall. The next logical step toward commercialization of this technology, requires generation of a data base by testing a larger size, more representative unit. 11 figs., 8 tabs.

• Research Organization: Brookhaven National Lab., Upton, NY (USA)
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 5913273
• Report Number(s): BNL-51939; ON: DE86008797
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
014000* -- Coal
Lignite
& Peat-- Combustion
ASHES
BOILERS
CARBONACEOUS MATERIALS
CHEMICAL REACTIONS
COAL
COMBUSTION
COMBUSTORS
COMMERCIALIZATION
CONCENTRATORS
CYCLONE SEPARATORS
DESIGN
DISPERSIONS
ENERGY SOURCES
EQUIPMENT
FOSSIL FUELS
FUEL SLURRIES
FUELS
HYDROGEN COMPOUNDS
INERTIAL SEPARATORS
MATERIALS
MIXTURES
OXIDATION
OXYGEN COMPOUNDS
POLLUTION CONTROL EQUIPMENT
RECOMMENDATIONS
REMOVAL
RESIDUES
RETROFITTING
SEPARATION EQUIPMENT
SLURRIES
SUSPENSIONS
TEST FACILITIES
THERMOCHEMICAL PROCESSES
WATER