Abstract

A COMPARATIVE STUDY OF THE PERFORMANCE OF ANAEROBIC DIGESTION OF SEAWEED (ASCOPHYLLUM NODOSUM) AT MESOPHILIC AND THERMOPHILIC TEMPERATURES

Obianuju Patience Jideofor, Joseph Akunna, C.O. Onyia1, & B. O Solomon

Global warming and other environmental issues associated with the consumption of fossil fuel have shifted attention to alternative energy such as renewable energy. At the forefront is biogas production from seaweed. The performance of the anaerobic digestion of brown seaweed (Ascophyllum nodosum) was conducted at mesophilic (37±20C) and thermophilic (55 ±20C) temperatures. Continuously fed single-stage reactors were analysed using seaweed substrate at different Organic loading rates in Hydraulic retention time of 20 days. The physico-chemical characteristics of the effluent such as pH and VFA were scrutinized. Biogas volume was measured using a water displacement system and its composition was monitored using gas analyser. There were accumulation of VFA and variation in pH value during the process, which was as a result of the increase in feeding rates. This accumulation of VFA affected the methanogens in the reactors. From the result, the thermophilic reactor produced higher biogas with less methane content while the mesophilic reactor produced low biogas with high methane content. For commercial use, the co-digestion process and the use of two stage reactors need to be considered.

Published Date: 2013-10-29;