TECHNOLOGIES DIVERSIFICATION AS A KEY FOR HIGHER ENERGY CONVERSION PERFORMANCE OF MAIZE CULTURE

Maize is the energy crop most widely used in biogas power plants. It is collected and stored through the silaging process of the whole plant. This work suggests a different way to proceed that takes advantages of the collecting method developed for food maize harvesting where the grains are separated from the corn cobs, leaves and stalks that composed the stover. This work demonstrates the advantages related to the implementation of a simple fixed bed gasification reactor in the biogas power plant. While the digestor is fed with grains, the stover is gassified and the two gas streams (biogas and syngas) are both used to fed the engine. The performance of this innovative method were evaluated using two coupled mathematical models of the anaerobic digestion and the gasification process. Results outlines that the stover is suitable for gasification, furthermore the overall energy yield of the coupled power plant is 39% higher than the equivalent conventional power plant fed with the same amount of maize. This method will improve existing power plants as well as will lead to the design of smaller and cheaper digester because most of the undegradable part of the plant is diverted into the gasifier.