Energy recovery potential in coupling of sanitation and agriculture: Techno-economic analysis on resource-oriented sanitation.

The coupling of sanitation system and agriculture production is essential to mitigate the environmental burden and offset unsustainable fertilizer utilization by employing resource-oriented sanitation. Yet, the economic feasibility and energy recovery potential from domestic waste have rarely been investigated. To assess four scenarios (whether with kitchen waste separation; whether with energy recovery) in the resource-oriented sanitation system, an integrated assessment framework based on energy analysis and techno-economic analysis is employed to investigate the comprehensive sanitation system including both wastewater treatment and solid waste disposal. The results show that energy recovery from human excreta and kitchen waste can offset the energy consumption of the sanitation system and the energy surplus can even be 1067.70 kJ·PE-1·day-1. The optimum covering range of the regional recovery center was quantified from the balance between scale effect and spatial distribution, and the serving inhabitants need to be more than 2800.