ical mounting position Type B Gear unit dimensions B3-FV-25-D Bevel-helical speed reducers B3

Flender/Flender Gear Units/Bevel-helical speed reducers B3

sion technologies of biomass or wastes include the following basic processes: 1. Thermal and thermochemical processing: combustion or incineration, pyrolysis or destructive distillation, gasication, liquefaction, and others 2. Chemical processing: production of pulp and paper, furfural, silica, silicon and silicates, and others 3. Biochemical processing: fermentation, biogasication, composting, and others In fact, both thermal and thermochemical technologies involve high temperature. These biomass conversion technologies are covered in this chapter. However, the commonmethods of waste disposal are land lling or sanitary land lling and disposal in rivers and the sea. 3 COMBUSTION Combustion is the process of liberation of heat by the oxidation of the combustible constit- uents of the fuel. Generally, fuels are compounds of carbon and hydrogen; in addition,variable percentages of oxygen and small percentages of sulfur and nitrogen are present. Biomass fuels are thermally degradable organic materials. The combustion of biomass fuels not only generates carbon dioxide and water vapor but also produces carbonaceousresidues, smoke, tar, and some harmful gases, such as carbon monoxide. Combustion andincineration are the same in principle. Incineration is used as common method of dispos-ing of solid wastes, such as municipal solid waste by high-temperature oxidation, thoughits primary objective is to reduce the volume of solid waste and its secondary purpose is to produce energy or to destroy putrescibles or hazardous wastes (6,. 3.1 Principles 3.1.1 Combustion ParametersThe fuels generated from plants are mainly composed of moisture and different organic and inorganic compounds. The effects of these on combustion are described in the follow- ing sections. 3.1.2 Moisture The raw wood plant residues, bagasse, etc., may contain high moisture, and these should be dried to lower moisture level. Some agricultural residues, namely, straw and husks, 8 Chakraverty have 8% to 1%