Reading guidance：Sewage disposal plants are spread in many places. At present have been completed and the sewage treatment plant many can not operate normally, to from time to time to open the stop, not only part of th

  Sewage disposal plants are spread in many places. At present have been completed and the sewage treatment plant many can not operate normally, to from time to time to open the stop, not only part of the production line, and some simply stopped, simply not up to design ability. County sewage treatment plant is more prominent, spent tens of millions or even hundreds of billion yuan of funds the project idle more than all. Results is not built sewage treatment plants, sewage everywhere flow; sewage treatment plant sewage concentrated flow.
  1. At present, many sewage disposal plants face with crisis. There are following elements which may affect the survival of sewage plants:
  A. Lack of fund
  Factories lack of money, operation is still short of money. Because of lack of money, one is sewage treatment fee standard is too low, the sewage treatment plant normal operation on the sewage treatment fee charged, and charges low, even in full charge also can not afford the cost of operation.
  B. No precise solution for sludge
  Experience in city sludge trapped, domestic urban sewage treatment plant sludge no way out: sewage treatment plant sludge outlet is almost always a tricky problem, are not very good solution can be said that the city has encountered the difficulties of sludge.
  With the development of social economy and urbanization, the production of municipal sludge is getting more and more.     According to incomplete statistics, our country city daily sewage discharge has reached 133.7 million tons. Sewage after treatment, the volume of 0.5% ~ 1% will be transformed solid condensates settling down, this is commonly referred to as sludge. According to estimates, at present China's urban sewage processing plant annual emissions of sewage sludge (dry weight) of about 900 million tons, accounting for 3.2% of China's total solid waste, and annual growth rate of more than 10%.
  The composition of sludge is very complex. It is composed of various microbes, organic matters and inorganic matters. Among the sludge, there are many organic matters, heavy metals and salts. A great amount of sludge are piled and discharged casually, which will cause new pollution. Especially in some cities with high urbanization, sludge disposal problem has been very prominent.
 C. How to dispose sludge effectively and safely has been an obligatory problem which must be faced by sewage disposal plants.
  2. Current situation and existing problem of sewage disposal plants in our country
  Urban sewage treatment plants become polluters! This is a let you accept the fact that some of the difficulties. In many people, including some leaders view, a city, as long as the establishment of the sewage treatment plant, water supply and environmental problems of the city resolving. And the truth is, urban sewage treatment plant in the sewage treatment process will produce sludge. And with the continuous improvement of the urban sewage treatment rate, sludge yield is also increasing. At present, the annual sludge produced reached a total of 900 million tons.
   At present, China's urban sludge treatment disposal methods in Agricultural Disposal about 44.8%, land landfill accounted for about 31%, other disposal of about 10.5%, there is no disposal of approximately 13.7%, these so-called "treatment" and "disposition" is basically is in specific conditions to estimate the strictly above digital there will be great changes. According to statistics, China for sludge treatment disposal investment accounted for about sewage treatment plant with a total investment of 20% to 50%, can be seen, the sludge treatment and disposal in lag.
Sludge treatment and disposal has been in big cities emerged. Early sewage treatment plant, due to the lack of strict supervision of sludge discharge, generally will sewage and sludge treatment stripping unit open, in order to pursue simple sewage treatment rate, as much as possible simplification, even ignoring the sludge treatment and disposal unit; some in order to save the operation cost will have been built by the sludge treatment facilities for long term idle, even without any treatment of wet sludge random Sinotrans, simple landfill or farmland directly, resulting in many big cities appeared phenomenon of the siege of sludge and has begun to spread to the small and medium-sized cities, to the ecological environment brings extremely unsafe hidden danger.
 3. Importance of sludge disposal and methods and analysis of sludge disposal
  A. Importance of sludge disposal
  Sewage treatment and sludge treatment and disposal is to solve the problem of urban water pollution are equally important and closely associated with the two systems. Sludge treatment and disposal of sewage treatment is the guarantee for the ultimately be implemented. In developed countries, sludge treatment and disposal is an extremely important link, the investment accounted for about sewage treatment plant with a total investment of 50 to 70%.
  B. There are some normal sludge disposal methods such as sea-fill, landfill, incineration and land utilization. Among these methods, sea-fill has caused serious pollution, so sea-fill method has been forbidden by international ocean law. Sea-fill has been abolished by many countries.
  C. All countries regard sludge disposal as a important link of sewage disposal system and devotes great investment, which will end pollution abatement perfectly. It is a mature sewage disposal method. Different countries adopt different methods which are suitable for real situations to dispose sludge.
  

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