Methane production for sanitation improvement in Haiti

Abstract

There is a great need for decentralized anaerobic digestion (AD) that utilizes wastewater for energy generation. The biochemical methane potential (BMP) of Haitian latrine waste was determined and compared to other waste streams, such as grey water, septage, and dairy manure. Average methane (CH4) production for the latrine waste (13.6 ml ml−1 substrate) was 23 times greater than septage (0.58 ml ml−1 substrate), and 151 times greater than grey water (0.09 ml ml−1 substrate), illustrating the larger potential when waste is source separated using the decentralized sanitation and reuse (DESAR) concept for more appropriate treatment of each waste stream. Using the BMP results, methane production based on various AD configurations was calculated, and compared with the full-scale field AD design. Methane potential from the BMP testing was calculated as 0.006–0.017 m3 person−1 day−1 using the lowest and highest latrine BMP results, which was similar to the values from the full-scale system (0.011 m3 person−1 day−1), illustrating the ability of BMPs to be used to predict biogas production from sanitation digesters in a smaller-scale setting.