Technical Study And Economic Analysis On Cycliing Municipal Organic Waste

Municipal Solid Waste is the main pollution in our country. The output of MSW is rapidly increased with the improvement of people's living standard every year. The new technology of treatment & disposal of MSW based on the principle of circular economy becomes the hot research topic as a newly improved idea and system.This paper firstly worked out a technical plan of cycling municipal organic waste according to the characteristic of high content of organic component in MSW, in which organic waste was transferred by the vacuum collection system, deposited in a pot designed especially, then pumped into Staged Multi-phase Anaerobic Digestion System(SMADS) periodically and the sewage treatment unit. The technical plan realized the source reduction and recycling of municipal organic waste.The lab-scale trial shows that under the different temperature, the efficiency of reduction and harmfulness in 35℃is 35.3% and 37.4%, the efficiency of recycling is 114.2 ml/gTS. Besides, under the different C/N of raw material, the efficiency of reduction and harmfulness in 25:1 of C/N is 35.1% and 39%, the efficiency of recycling is 165.1 ml/gTS. This is the highest between all the parallel trials.A device which can disposal 0.2t per day was developed based on the trial data of lab-scale. After 35 days'trial run, the efficiency of reduction and harmfulness of the anaerobic digestion unit is 36.1% and 33.8%, the efficiency of recycling is 126.7 ml/gTS. The output concentration is between 300~400mg/l in the sewage disposal unit, and the bacterial fertilizer was proved effective. The results are encouraging considering that all the reaction condition can not be strictly met. The whole device worth running furthermore in order to complete the plan and layout.The cost-benefit analysis demonstrated that the system could make profit at the scale of 100 households. The more the scale is, the shorter the durance to get back the investment. When it had reached 5000 households, IRR is 45%, NPV is 25.5591 million yuan. Besides, green input-output checking system was involved as a new tool of technical and economic analysis.