Scale effect of modelling on biogas generation

Abstract

Anaerobic decomposition of manure i s an outstanding alternative energy source, appropriate for most developing countries. Several studies related to this subject were conducted so far, however, the effect of the size of the inodel on the efficiency obtained was not investigated. The main purpose of the present study was t o investigate, the scale effect on the perfomance of an anaerobic digestion. To achieve this three digesters , each of different size and voluue, were installed and operated under ambient conditions. The results obtained have shown that: 1. The size of the model has as light effect on the efficiency of anaerobic digestion, better performance being obtained in larger model. 2. Any digester can be operated under ambient conditions if proper insulating precautions are taken. 3. Mixing has a positive effect on biogas generation. 4. The positive effect of yeast on anaerobic decomposition is verified .