ANAEROBIC CO-DIGESTION OF DIFFERENT MIXTURES OF ORGANIC WASTES – OUR EXPERIENCE

Abstract

Anaerobic digestion is a biotechnological method of biogas generation from organic wastes. Anaerobic co-digestion can be considered as the instantaneous anaerobic digestion of two or more substrate and co-substrate mixtures. Anaerobic co-digestion is a pragmatic method to resolve the difficulties related to substrate properties and system optimization in single-substrate anaerobic digestion. During the last two decades our multidisciplinary team performed a lot of experiments of anaerobic co-digestion of different organic wastes activated sludge, cattle manure, swine manure, milk whey, wasted fruits and vegetables etc. Different ratios of mixtures of these organic wastes, in binary and triple mixtures, have been investigated in view to maximize the obtained energy (methane) production. The time for reaching of the process steady state in laboratory anaerobic digesters have been determined to be ten days’ period. Results obtained have shown that some binary mixtures are more perspective in regards to biogas production optimization. It has been found that the addition of 3rd substrate to some binary mixtures could lead to decrease of bioprocess effectiveness.