Anaerobic digestion is a biological process in which the organic material is converted by microorganisms to methane and carbon dioxide (biogas) in the absence of oxygen. This process is interesting but the control on industrial scale spontaneous biological reactions requires good knowledge of the phenomena involved. The search for appropriate models to be use in control theory is now a high priority to optimize fermentation processes and solve important problems, such as the development of renewable energy from biodegradable organic waste. The aim of this study is modeling of biokinetics of anaerobic digestion on several aspects such as microbial activity, substrate degradation and methane production. For this, we developed a mathematical model based on mass balances on biomass, the organic substrate and biogas. This model is then simulate on Matlab using the experimental data from the literature and comparison between other models and our experimental results. The sensitivity of the model to the process parameters was study by varying the initial concentration of the biomass and the dose of the organic substrate.

No abstract

No abstract

Anaerobic digestion is a biological process that takes place under very strict operating conditions, including a pH close to neutrality. This experimental work aims to study the effect of pH control on CH4 production in mesophilic anaerobic co-digestion of cheese whey with cow manure. Two experiments were conducted in batch reactor, the first without pH adjustment and the second with pH adjustment. The results of the first co-digestion revealed an inhibition of the methanization process by acidification of the medium and accumulation of volatile fatty acids; whereas during the second co-digestion with pH adjustment by sodium bicarbonates (1M), the process was improved with methane levels (> 50%) in the biogas. The accumulated biogas volume was two times higher for the same operating time in the digester.

Slaughterhouses generate highly polluted effluents, and if not treated before discharge can cause major adverse environmental and public health impacts. Treatment of this waste by anaerobic digestion can reduce those impacts while producing a potentially valuable source of energy. The purpose of this study was to investigate this process efficiency under pilot operating conditions for a more accurate scaling up. Blood waste from a slaughterhouse was treated in a pilot-scale digester of 30 dm 3 total volume under mesophilic temperature conditions. Operating parameters