Biological Purification System: Integrated Biogas from Small Anaerobic Digestion and Natural Microalgae

Photosynthetic pigments, including chlorophyll, have an important role since they provide the oxygen and the source of energy for all living things. Plant and algae growth is affected by the photosynthesis speed which depends on the availability of carbon dioxide (CO2). This paper reports on the pilot plant scale study of the impact of 20% to 50% CO2 on biogas into the growing medium of microalgae which obtained bio-methane purification results as gaseous bio-fuels. Research material was produced from the Jatropha curcas Linn. husk biogas digester and a 0.15 m3 HDPE drum was used as a purification. The purification tank was filled with Catfish (Clarias gariepinus) farm water which grew “wild” microalgae naturally. The water was fed from the top with continuous flow of (16 to 31) L· min–1 and the biogas was fed from the bottom at (18 to 29) L · min–1. CO2 level data of biogas was measured by orsat apparatus and processed with t test. The results achieved average efficiency reduction levels of CO2 on 50% in two cycles (24% in the first and 26% in the second).