Ceramic single-ended recuperative radiant tube (Phase 1). Final report, November 1986-December 1989

Technical Report · Mon Jan 01 04:00:00 EST 1990

OSTI ID:5347208

Singh, S N; Gorski, L M

A silicon carbide single-ended recuperative radiant tube (SER) combustion system was developed to compete against electric heating elements which can operate at higher heat fluxes and furnace temperatures than metallic gas-fired systems. The silicon carbide SER system resulted in 50% or higher thermal efficiency depending upon the operating temperature and heat flux. Two industrial batch-type heat-treating furnaces with process temperatures of 1450 to 1750 F were retrofitted with 3-1/4 in silicon carbide SERs operating at heat fluxes of 100 to 150 Btu/hr/in2. The SERs replaced conventional straight-through radiant tube combustion systems with efficiencies less than 30% and limited to heat fluxes less than 55 Btu/hr/sq in. After a year of operation, the hosts reported a 35% increase in furnace productivity and 40 to 50% fuel savings. Experience indicated that reaction-bonded silicon carbide radiant tube applications should be limited to a 2200 F chamber temperature and a heat flux of 200 Btu/hr/in2. Beyond this, tube life is unpredictable. The SERs may be applied to process temperatures of 2300 F, provided the heat flux is lowered to 150 Btu/hr/in2. NOx levels of 150 to 200 ppm have been recorded for a heat flux of 200 Btu/hr/in2 and 1800 to 2200 F chamber temperatures. Investigations are under way to further reduce NOx formation in high temperature applications.

• Research Organization: Eclipse, Inc., Rockford, IL (United States). Combustion Div.
• OSTI ID: 5347208
• Report Number(s): PB-91-222554/XAB; CNN: GRI-5086-234-1310
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320303* -- Energy Conservation
Consumption
& Utilization-- Industrial & Agricultural Processes-- Equipment & Processes
42 ENGINEERING
421000 -- Engineering-- Combustion Systems
CARBIDES
CARBON COMPOUNDS
CHALCOGENIDES
CHEMICAL REACTIONS
COMBUSTION
COMBUSTION CHAMBERS
COMBUSTION PRODUCTS
EFFICIENCY
ENERGY CONSERVATION
ENERGY SOURCES
ENERGY TRANSFER
FLUIDS
FOSSIL FUELS
FUEL GAS
FUELS
FURNACES
GAS FUELS
GASES
HEAT FLUX
HEAT TRANSFER
NATURAL GAS
NITROGEN COMPOUNDS
NITROGEN OXIDES
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PERFORMANCE
PRODUCTIVITY
RADIANT HEAT TRANSFER
REGENERATORS
SERVICE LIFE
SILICON CARBIDES
SILICON COMPOUNDS
THERMAL EFFICIENCY
THERMOCHEMICAL PROCESSES
TUBES
VERY HIGH TEMPERATURE