Abstract
In this paper, the use of water hyacinth as a feedstock for methane digester was examined. The main idea behind this work was how to make use of a resource (water hyacinth) that might otherwise have gone to waste. Biogas was produced from this digester which is a burnable fuel. Moreover, the digester sludge was used as fertilizer. Jeddah Waste Water Treatment Plant is a small plant with a total area of 4200 m2 of ponds that could be used to produce water hyacinth when the plant operates at its full capacity. The following tasks were accomplished in sequence; sizing the digester, sizing the inlet and outlet tanks, designing the digester walls, sizing and designing the gas holder, and estimating the amount of insulation needed. It was found that the digester is able to produce approximately 9.55 m3/day of biogas.