Thermophilic co-composting of human wastes in Haiti

摘要

Sustainable Organic Integrated Livelihoods (SOIL) is an organization that has been working on ecological sanitation in Haiti since 2006 and, in 2009, developed the nation's first waste treatment site to treat human faeces using thermophilic co-composting. Since the earthquake in 2010, SOIL has developed a composting design that eliminates pathogens and creates a re-usable nutrient-rich compost. This paper provides an overview of SOIL'S thermophilic composting model in a low-resource setting, highlighting the mechanisms of effective pathogen elimination in the system. SOIL'S model creates a composting environment in static bins that reaches and maintains temperatures of over 65 °C for more than 1 month. Temperatures are monitored regularly and have been revealed not to be homogeneous throughout the piles. A 2012 collaboration with the US Centers for Disease Control and Prevention (CDC) showed rapid pathogen die-off rates within the compost piles, reducing E. coli levels to below detection levels within 14 weeks and rendering Ascaris ova not viable within 8 weeks. In order to increase the efficiency of the process and ensure that this compost is pathogen- free, SOIL will continue to refine the composting design, including piloting a new turning scheme, and identifying a procedure for regular pathogen testing.