Hydrogen and electrical energy from organic waste treatment

Abstract

This paper presents the design details of a biogas gas plant and fuel cell installation that will provide a practical solution on an island (and be applicable in other remote and rural areas) where connection to the grid can be expensive, and where biofuels can be produced on site at no significant extra cost. In situ use of biomass and organic waste streams have the potential to provide the key to energy recovery and sustainability from biodegradable waste. The scheme described in this paper meets the new EU regulations covering (i) the landfill directive, (ii) the animal by-products regulations, and (iii) the biowaste directive. Traditionally biogas fuels have been used in combustion engines for electric power generation. However, there are now clear indications that given the current developments in reformer technologies, hydrogen gas can be produced from methane-derived anaerobic digestion of organic waste material—much of which is currently land filled. Hence, when utilized in fuel cells this offers the prospect of achieving higher generating efficiencies, and additionally, important environmental benefits will be achieved through mitigating greenhouse gas emissions. The solid waste from the process provides a valuable organic fertiliser which can be returned to the land thereby displacing chemical fertilisers currently in wide spread use.