ABSTRACT Sustainable organic integrated livelihoods (SOIL) operates a household container-based sanitation service in Cap-Haitien (Haiti), where urine-diverted fecal sludge is composted with sugarcane bagasse. SOIL investigated the feasibility of transitioning from bin composting associated with windrow composting (current system) to exclusively windrow composting (pilot). This study aimed to assess whether safety requirements for fecal sludge treatment were met, and whether the pilot was more efficient than the current system. Both systems complied with World Health Organization guidelines for safe composting of fecal sludge (50 °C for 107 and 67 days, respectively, 10 colony forming unit Escherichia coli/g of compost). The final compost exhibited low pH (around 5.5) and high electrical conductivity (around 4 dS/m), suggesting it could be phytotoxic to sensitive plants. This may be attributed to the use of sugarcane bagasse, as well as the prolonged high pH (9) and temperature (65 °C) during a prolonged thermophilic phase (3 months). We found that the system type may have a greater influence on temperature development than pile size or turning frequency, and that turning piles once per month appears sufficient to maintain favorable composting conditions. Overall, the pilot system demonstrated advantages in terms of time to reach compost maturity, operational ease, and cost efficiency.
Ward et al. (Thu,) studied this question.