Reading guidance：With the rapid development of Chinas urbanization, city sewage volume continues to increase, which is also one of the main reasons causing regional water pollution in our country. In order to cope with

      With the rapid development of China's urbanization, city sewage volume continues to increase, which is also one of the main reasons causing regional water pollution in our country. In order to cope with the challenges of water resources, the state and governments at all levels improve the importance of environmental protection. Since 12th Five-Year, sewage treatment capacity and treatment rate increased rapidly. According to Ministry of housing and urban rural construction on the bulletin of the national urban sewage treatment facilities construction and operation of the first quarter of 2014, it showed that at the end of March 2014, the National City, county (hereinafter referred to as the "town", excluding other towns) completed a total of 3622 sewage treatment plants, sewage treatment capacity of about 153 million cubic meters one day. Compared with growth of 22.1%, the number of statistics in 2010 rises about 20% for processing capacity.
    However, new environmental problems are coming. After treatment, there will be 0.5% to 1% solid condensation formed, which is generally called sludge . According to relevant estimates, sludge discharged amount of municipal sewage disposal plants reaches to about 30000000 tons which accounts for about 17.4% of total. According to statistics of department of housing, safe guarantee rate in our sewage disposal plants is lower than 35%. Sludge without harmless disposal is littered casually and cause secondary pollution. It is still an urgent task to drive harmless, stable and reclamation. Relevant government should strengthen supervision. Under present situation which attaches much importance to sludge disposal, only have a good command of market, can we be outstanding in sludge disposal market. In recent years, sludge disposal in china develop rapidly, but we still face with some challenges. In China there is a serious "heavy light mud" to cope with the situation because of the rapid development of urbanization brought increasingly significant environmental problems, countries in recent years has been gradually increasing emphasis on environmental protection, and strengthen a series of policies and funds support. During 12th Five-Year, the urban sewage treatment and recycling the main task of planning facilities, investment totaled 427 billion 100 million yuan, 332 billion yuan in 11th Five-Year investment growth of 22.3%, while the 12th Five-Year investment plan, the new sludge treatment and disposal of investment of 34 billion 700 million yuan, compared with 11th Five-Year 32 billion 300 million investment grew 6.9%. from this data we can see that our country still exists serious "heavy light mud" the situation, the government invests much to sludge industry, which is a main reason why we lag behind in this 10 years.
Immature products
    Having experienced 50 years of ups and downs, the cause of sludge disposal treatment in China before the reform and opening up, as the sewage treatment plant is less in China, simple treatment after the sludge as manure has not caused environmental problems; from 1980s until today, the rise of urbanization leads to a large number of construction of city sewage treatment plant, a large number of sludge makes its processing the disposal problems have become increasingly prominent, and has become a difficult problem in the sewage treatment industry. The town has nearly a hundred years of sludge treatment and disposal of the history of compared with the developed countries in Europe and America, sludge treatment and disposal in our country is still slightly tender. A prominent problem is: sludge treatment technology, but did not form a "All flowers bloom together." a mainstream. Processing technology has not mature. Some technology can fully meet the disposal standards.

      According to statistics of JIEITRACKER, on the choice of sludge disposal technical road, drying incineration, aerobic fermentation and anaerobic digestion of the market     share accounted for by 54.9%, 27.6% and 13.1% respectively. Other technical routes account for 7.9%. Comparing from a technical difficulty, difficulty of the landfill is the lowest, followed by the use of land, the difficulty of burning is the highest. one-time investment is large, the latter part of the maintenance cost is high. Thus, in the sludge treatment and disposal field, technology has not hinder main problems.

Cost problems restrain development
      Circulating economy is to achieve sustainable development for a long time. After disposal, urban sewage contains rich organic matters. If these organic matters are utilized fully, harmless sludge can be got and recycle benefits can be realized. But, there are some harmful matters in sludge. Therefore, whether we can reduce the total amount of sewage has been as very key problem.
      In recent years, our country adopts incineration, land use and building materials. According to sludge management data incomplete statistics of environmental protection industry tracking (JIEITRACKER), our country holds harmless, resource processing and sludge disposal center. In addition to the sanitary landfill, incineration power generation, reuse of land and building materials, other technologies account for 38.6% of the market share. Thus, sludge resources in our country mainly choose incineration and land reuse as disposal methods.
      No matter which disposal roads you take, cost is a main restrict condition which is considered much in the process of sludge disposal. According to data of geographic sciences and natural resources research institute, the landfill costs about 350 to 500 yuan/tDS. The cost for incineration is about 800 to 1000 yuan/tDS. Cost for composting is the lowest (about 300 to 500 yuan/tDS). Considering costs of these three methods, use composting properly is one of main technical direction.
     Besides, government will launch proper allowance. Taking advantage of the function of economy to control input and output. It will also have great influence to sludge disposal.
 

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