Advanced coal-fueled combustor for residential space heating applications: Topical report: Combustor design definition for the period 1 October 1986-30 April 1987

Technical Report · Mon Jun 01 04:00:00 EDT 1987

OSTI ID:6220563

Ruth, L A; Chen, S L; Kwan, Y; Sommer, T M

This report reviews combustor design concepts for an integrated combustor/heat exchanger which burns coal either as a slurry or as dry ultrafine coal and which is suitable for use in a range of residential space heaters. The performance goals for the combustor include a combustion efficiency exceeding 99%, rapid response time (less than 5 min to full load), reliability and safety comparable to oil-fired systems, no daily maintenance with scheduled maintenance not more frequent than twice a year, and a service life of 20 years. The important combustor design considerations are combustion chamber size (i.e., coal residence time), burner type and configuration, wall temperature, atomizer type/droplet size, pilot flame size, and the operating air preheat and excess air levels. Modeling of the combustion process showed that a fuel residence time of one second would be adequate to achieve 99% carbon burnout of ultrafine coal (with a maximum particle size of 40 ..mu..m) or a coal slurry (with a 500 ..mu..m droplet size), provided that agglomeration of coal particles does not occur. This residence time translates into a combustor volume of 2 ft/sup 3/, for example, a cylindrical chamber 1 ft in diameter and 2-1/2 ft long. Two types of burners are judged suitable for use in a coal-fired residential heater: swirl stabilized and hot refractory quarl stabilized. Various burner configurations utilizing these two principles will be evaluated during experimental testing. Wall temperature is another important design parameter which impacts on both material of construction and combustor performance. The choice of construction materials include stainless steel and refractories. A steel wall, while probably more durable than refractory, would need to be cooled.

• Research Organization: Energy and Environmental Research Corp., Irvine, CA (USA)
• DOE Contract Number: AC22-86PC90279
• OSTI ID: 6220563
• Report Number(s): DOE/PC/90279-T8; ON: DE87014210
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
014000* -- Coal
Lignite
& Peat-- Combustion
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320106 -- Energy Conservation
Consumption
& Utilization-- Building Equipment-- (1987-)
BUILDINGS
BURNERS
CARBONACEOUS MATERIALS
CHEMICAL REACTIONS
COAL
COMBUSTION
COMBUSTORS
DESIGN
EFFICIENCY
ENERGY SOURCES
FOSSIL FUELS
FUEL-AIR RATIO
FUELS
HEATING
MATERIALS
OXIDATION
RESIDENTIAL BUILDINGS
SPACE HEATING
SPECIFICATIONS
THERMOCHEMICAL PROCESSES