TESTING OF KINETIC-MODELS OF BIOGAS PRODUCTION FOR A SEMICONTINUOUS DIGESTER USING COWDUNG AS FEEDSTOCK

Three kinetic models developed to predict the behaviour of semicontinu ous mode of anaerobic digestion are briefly discussed in the present a rticle. These models have been tested at Bangladesh under laboratory c ondition susing slow rate semicontinuous systems. The process was run in a two and a half litre glass reactors, using cattle dung as feedsto ck, at room temperatures ranging from 22-35 degrees C. As soon as the reactors seemingly reached a stable condition observations were taken stretching over several days. The experimental data nicely fitted to t he models. The gas yield constant C was found to be 0.872 m(3)/kg dige stible volatile solid. The kinetic rate constants were found to be 0.0 17/day, 0.0082/day and 0.204 from the Pfeffer's, Lau Wong's and Chen a nd Hashimoto's model respectively. The kinetic constants obtained from the laboratory level semicontinuous digesters may be useful for a ful lscale digester operating under similar conditions.