Process design for decentralized sewage treatment system with total natural resource management

In developing countries sewage disposal is still a major problem. Increase in population and less availability of natural resources makes sewage a major source of health hazard. With sprawling urban population sewage disposal has become a very serious problem. Under this circumstances, the decentralized sewage treatment system (DTS) for population varying from 1000 to 10,000 that is, 120 to 1200 Kl/day or more can play a major role in water pollution abetment with multifaceted benefits. In this paper a realistic and low maintenance process design of DTS with cost benefit analysis for a population of 3000 is discussed. This process with indigenous technology makes sewage a resource providing biogas as fuel, biofertilizer and manure rich water for irrigation purposes. The amount spent on this sewage treatment can be fully recovered within 8 to 10 years. Thus we can find solution to a formidable problem which either seems impossible and total natural resource management is possible through adopting it.     Key words: Decentralized sewage treatment system (DTS), natural resource management, sewage disposal.