Sustainable community sanitation for a rural hospital in Haiti

A fully sustainable sanitation system was developed for a rural hospital in Haiti. The system operates by converting human waste into biogas and fertilizer without using external energy. It is a hybrid anaerobic/aerobic system that maximizes methane production while producing quality compost. The system first separates liquid and solid human waste at the source to control carbon to nitrogen ratio and moisture content to facilitate enhanced biodegradation. It will then degrade human waste through anaerobic digestion and capture the methane gas for on-site use as a heating fuel. For anaerobic decomposition and methane harvesting a bioreactor with two-stage batch process was designed. Finally, partially degraded human waste is extracted from the bioreactor with two-stage batch process and applied to land farming type aerobic composter to produce fertilizer. The proposed system is optimized in design by considering local conditions such as waste composition, waste generation, reaction temperature, residence time, construction materials, and current practice. It is above ground with low maintenance requirements.