Spatial-temporal economic analysis of modern sustainable sanitation in rural China: Resource-oriented system

Sustainable sanitation is developed in order to create an efficient and ecological use of water, energy and nutrients, the basic elements important for living beings. However, the sustainable sanitation is still doubted by authority and there is no large-scale implementation when wastewater treatment campaign significantly carries out in rural China. The lack of economic feasibility assessment is a major barrier to break through the current wastewater treatment paradigm. This study aims to evaluate the economic performance and feasibility of resource-oriented system, an innovative sustainable sanitation, based on vacuum pipelines technology and source separation. For this purpose, life cycle cost analysis for conventional wastewater treatment and resource-oriented system in different population sizes was studied. Considering the spatial distribution of households, an important and remarkable factor in rural China, the paper innovatively instigated the balance between the economies of scale and decentralization. Results show that resource-separated system with positive environment and social effects outperforms current system in terms of lifetime cost because of its lower energy consumption and sewer cost. Based on the discussion, the optimum collection scale is not fixed and decided by local market situation. Commonly speaking, village-group model is preferred for conventional wastewater treatment system in rural China. Considering the factors of biogas utilization, pipe airtightness and financial pressure, both centralized and decentralized model can be chosen in resource-oriented system.