Combustion characteristics in fluidized-bed furnace for power generation system using livestock wastes

This paper describes a study on combustion of livestock wastes for developm ent of a power generation system using them. Broiler, layer and swine excre ments are used as fuel. The relationship between calorific value and moistu re content is examined. Although moisture content of the prepared livestock wastes shows sufficient fluctuations (10-80 wt%), it does not strongly aff ect the lower calorific values on a dry basis. The livestock wastes are burned using an established test fluidized-bed fur nace. Because moisture content of the swine excrement is very high (80 wt%) , swine excrement is mixed with other livestock wastes to decrease the mois ture in the fuel. The combustion efficiency, which is defined as the ratio of the heat generation in the fluidized bed to the calorific value of the s upplied fuel, is evaluated using a heat balance in the fluidized bed. On th e basis of the results, an empirical equation for estimating the combustion efficiency is presented. The fluidized-bed temperatures estimated using th e empirical equation and the heat balance almost agree with the experimenta l ones.