Economic Analysis And Comparing Study On Disposal Technologies For Sludge From Municipal Sewage Treatment Plant

With the development of the industry and the increase of urban population, urban sewage emissions is increasing, a by-product of urban sewage treatment, sludge also increase, if the sludge disposal is undeserved, in the atmosphere, water, soil, will cause pollution and harm, causes in the treatment of wastewater at the same time to create new and more serious pollution.Under this background, in the face of sludge disposal is a worldwide difficult problem, the old technology innovation progress unceasingly, the new technology is also in constant development and experiment of a multitude of sludge disposal technology also has given rise to many new sewage treatment plant construction, some old sewage treatment plant is also changing to update their sludge disposal scheme. One of the important factors of sludge disposal scheme selection, is economic factor.In this paper the composition and characteristics of urban sewage treatment plant sludge at home and abroad, treatment and disposal technology and other related information, on the basis of consulting literature materials, based on the influence factors such as economy, technology, environment, analyzed the working principle, technical management requirements of the applicable conditions, restriction conditions.On this basis, for the current typical sludge landfill and sewage sludge compost technology has carried on the on-the-spot investigation, through the study on the engineering economic theory calculation, and compares the supplemented by DEA model, economic analysis conclusion, for the sewage treatment plant of technical selection of sludge disposal provides a certain theoretical basis. Finally, the existing problems put forward the corresponding improvement Suggestions. The conclusion is summarized as follows:(1) Composting disposal research instanceEngineering conclusion:?a north-eastern sewage treatment plant of hubei worm composting sludge disposal system with a total investment of 13 million yuan, the equipment investment is 3.6214 million yuan, the construction of 5.3943 million yuan, the installation of 810000 yuan, other costs 3.0776 million yuan.?Sludge moisture content was 80%, the unit average total cost is 107.07 yuan per cubic meter, the unit operation cost is 50.51 yuan per cubic meter.?Project pretax financial internal rate of return is 0.87%, pre-tax payback period is 20.04 years.Economic benefits: after the completion of the project can produce organic fertilizer 2190 tons a year, can output the earthworm 36 tons of goods, in accordance with the fertilizer 400 yuan/ton, commodity earthworm 10 yuan/kg, the price of the annual income of up to 1.236 million yuan.(2) Landfill disposal research instancesEngineering conclusions: ?the sludge landfill disposal system with a total investment of 54.29 million yuan, the equipment investment is 13.8171 million yuan, 20.67 million yuan construction, installation of 8.5171 million yuan, other costs 9.9958 million yuan.?Sludge moisture content was 80%, the unit average total cost is 79.30 yuan per ton, unit operation cost is 23.54 yuan per ton.?Project pretax financial internal rate of return is 0.18%, pre-tax payback period is 10.93 years.Economic benefit: the project operation, waste(sludge) disposal fee of 80 yuan per ton, to dump at full capacity then disposal expenses can achieve 7.3 million yuan a year.(3)Through engineering economic analysis and DEA model, that is suitable for small scale sewage treatment plant sludge disposal technology in China are: the sludge compost.(4)Main Suggestions: sludge disposal is one of the sewage treatment plant is very important link, and with the improvement of sewage treatment, the progress of the whole sewage treatment system, the proportion of sludge disposal expenses in the sewage treatment cost is becoming more and more big, the abroad advanced wastewater treatment has been reflected in the system. This article put forward the following Suggestions:?The domestic sewage treatment should pay more attention to sludge disposal, put more money and attention on sludge disposal, and actively research new sludge disposal technology.?Should increase the intensity of environmental regulation, for sewage treatment plant attaches great importance to the sludge disposal regulation, avoid sewage treatment plants in order to reduce the cost of sewage treatment and sludge.?Make some publicity for fertilizer of sludge composting process,reassure buyers prejudice against sludge fertilizer, open the sludge fertilizer sales market, make the sludge recycle more smoothly.