Biomass boilers

Small scale biomass boiler (room heating) for wood and pellets... 

Alkali Deposits Found in Biomass Boilers The behavior of inorganic material in biomass-fired power boilers - field and laboratory experiences, NREL/TP-433-8142, SAND96-8225 VII. 

Baxter L. Miles, Sr., T. Miles, Jr., T. Jenkins, B. Dayton, D. Bryers, R. Olden, L. Alkali Deposits Found in Biomass Boilers, Vol. II, NREL/TR433-8142, SAND96-8225,1996. 

Farmers are encouraged to consider their on-farm energy policies irsing technologies such as photovoltaic cells (solar panels), wind turbines, grormd heat pumps, biomass boilers and anaerobic digesters to produce electricity. 

Although the chemical analysis of biomass does not reveal directly any alarming concentrations of corrosive elements, there is one fundamental difference between fossil and biomass fuels that can be derived from it. This is the excess of alkali metals compared to the amount of sulfur plus chloride. Even if one assumes that all the sulfur in the fuel is reacted to alkali sulfates and all the chloride is reacted to alkali chlorides, there is still excess alkali left in biomass whereas with the fossil fuels this is not the case. The free alkali index has been used to predict the existence of alkali hydroxides in a biomass boiler [3] ... 

These recent findings suggest that condensation of KCl(g) is not the only, and perhaps not even the most important, deposit growth initiation mechanism in biomass fired boilers. Figure 28.3 presents the proposal for the test environment that could be used to better simulate the alkali corrosion in biomass boilers. 

Proposed test environment for the simulation of high temperature alkali corrosion in biomass boilers. 

Waste activated sludge Waste biomass Waste-derived fuels Waste disposal Waste-heat boiler... 

D. Tillman, E. Hughes, and B. Gold, "Cofiring of Biofuels in Coal Eked Boilers Results of Case Study Analysis," Proceedings First Biomass Conference... 

V. Nast, G. Ekschele, and W. Hutchinson, "TDE Co-firing Experience in a Cyclone Boiler," Proceedings, Strategic Benefits of Biomass and Waste Fuels Conference, EPRI, Washington, D.C., 1993. 

Most electricity from biofuels is generated by direct combustion. Wood fuels are burned in stoker boilers, and mill waste lignin is combusted in special burners. Plants are generally small, being less than 50 MW in capacity. There is considerable interest in combustion of biomass in a process called cofiring, when biomass is added to traditional fuels for electricity production. Cofiring is usually done by adding biomass to coal, but biomass also can be cofired with... 

Another emerging area m biofuels is pyrolysis, which is the decomposition of biomass into other more usable fuels using a high-temperature anaerobic process. Pyrolysis converts biomass into charcoal and a liquid called biocrude. This liquid has a high energy density and is cheaper to transport and store than the unconverted biomass. Biocrude can be burned in boilers or used in a gas turbine. Biocrude also can be chemical by altered into other fuels or chemicals. Use of pyrolysis may make bioenergy more feasible in regions not near biomass sources. Biocrude is about two to four times more expensive than petroleum crude. 

Waste-heat and other special-purpose boilers Special designs provide boilers for waste heat and chemical recovery, waste-to-energy, and combined-cycle installations, pulverized-bed, and even biomass applications. 

The majority of these operations use boiler technology, which involves the direct combustion of biomass materials... 

Biomass gasifiers have the potential to be up to twice as efficient as using conventional boilers to generate electricity. For even greater efficiency, heat from the gas turbine exhaust can be used to generate additional electricity with a steam cycle. These improvements in efficiency can make environmentally clean biomass energy available at costs more competitive with fossil fuels. 

Tampella Power Inc. Biomass, coal LHV Fuel for gas turbines, boiler fuel 40 290-334... 

Thermal Process Studsvik (TPS) (Studsvik Eneriteknik AB) Woody biomass LHV Fuel gas, duel fuel engine, gas turbine, boiler/furnace/ kiln fuel 13-78 (upper limit commercial) 14.7... 

Baxter, L.L., T.R. Miles, T.R. Miles, Jr., B.M. Jenkins, T.A. Milne, D. Dayton, R.W. Bryers, and L.L. Oden, 1997b. The Behavior of Inorganic Material in Biomass-Fired Boilers An Overview of the Alkali Deposits Project. Developments in Thermochemical Biomass Conversion, A.V. Bridgwater and D.G.B. Boocock, eds. Blackie Academic and Professional Press, London, pp. 1424-1446. 

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