Impact of hydrogen potential on anaerobic digestion of organic waste

¹ Laboratory of Industrial Processes, Environmental Synthesis and New Energies (LAPISEN), National Polytechnic Institute Houphouet-Boigny, P.O box 1093, Yamoussoukro, Côte d’Ivoire.
² National Center for Development of Technologies, Ministry of Scientific Research and Innovation (CNDT/MINRESI), P.O. Box: 1457 Yaoundé-Cameroon.
³ Laboratory of Thermodynamics and Physico-Chemistry of the Environment (LTPCM), UFR-SFA, UFR-SFA, University Nangui Abrogoua, 02 PO Box 801 Abidjan 01, Ivory Coast.

^* Corresponding author: okaridio@yahoo.fr

Abstract

The world’s waste deposit has become more important due to the growth of the world economy and demography. Biomethanation is method of choice for the treatment of fermentable fractions of municipal waste. However, low methane yield due to operational issues and process instability prevent this technology from being widely applied. It shows that biogas is made up of approximately 50-70% CH₄; 30-50% CO₂ from traces of other gases. Solutions for improving CH₄ production include controlling anaerobic digestion factors. These factors are essentially: the methanogenic potential, the carbon/nitrogen ratio (C/N), temperature, Hydrogen potential (pH) and tightness of the reactor. Among these factors, one of the most important, the pH, is analysed in this article in order to ensure production’s optimization. 02 substrates are studied potato peel and cow’s stomach waste: As results, the production of biogas varies constantly with the variation of pH. With a pH lower than 5 the production decreases. The best productions were obtained pH value between 6.9 and 7.4. That said, it is important to find a way to stabilize the pH variation in the production of biogas for better sustainability. Eggshell has been studied in order to maintain the balance and good results have been obtained.