Conclusion

The costs of MSW collection, transport, processing and disposal is gradually becoming expensive and even less sustainable.  There is a need to treat the MSW nearer the source so that segregation and recovery of recyclables are more efficient.  This calls for a decentralized system within localities. Decentralized systems run so far have had aesthetic (smell and insect) and economic problems and have always been short lived.  Running these sustainably in a decentralized manner requires firstly a good technology such as biomethanation (to first avoid smell and insects) that provides many more revenue streams (as from sale of biogas, C-credits, avoiding insecticides, avoiding methane emissions, compost, etc.) and secondly reasonably good recovery and sale of recyclables.  In this paper we also show that the biomethanation based decentralized systems have lower business risks because of a large spread of revenue streams.  This also avoids expenditure of over 1500/t for the municipalities and ULBs which becomes a big saving and can be invested in development.  It is therefore important that this concept be tried with at various municipalities so that we could become zero-waste cities of the future.