Development of Biogas Scrubber Using Water Purification System

Abstract

Biogas can be used in the production of electricity, for heating and cooking. In compressed form, it can be used to replace compressed natural gas used in vehicles, such that it can fuel an internal combustion engine or fuel cells. Cleaning of gas is necessary to meet the pipeline quality requirement. The composition of the gas must be correct to be accepted by the local distribution network. Carbon dioxide (CO2), moisture, hydrogen sulfide (H2S), and particulate matter must be removed if present. This study aimed to develop a biogas scrubber using water purification system. Specifically, the objective was to evaluate the composition of biogas before and after scrubbing in terms of percentage methane (CH4), CO2, Nitrogen (N2), and H2S. The development of the biogas scrubbing machine considered system components and material specifications. After fabrication, preliminary testing was done to establish different parameters such as working pressure and scrubbing time and amount of water needed. The study also evaluated the performance of the biogas scrubber in terms of percentage increase in CH4 and scrubber efficiency. An operation and maintenance manual for the utilization of the biogas scrubber was also prepared. After several trials and testing, the system inlet pressure operated at 4.6 psi. The system could increase CH4 in biogas by approximately 21.67 %. The scrubber efficiency was 68.67 %. It was recommended that further study should be conducted and consultation with experts should be done to improve the design and automate the operation of the system.