Reading guidance：For a long time, China has always attached great importance to the sewage treatment capacity. Especially after the 20th century, Chinas urbanization process is accelerating, constantly improve the leve

   For a long time, China has always attached great importance to the sewage treatment capacity. Especially after the 20th century, China's urbanization process is accelerating, constantly improve the level of urbanization, sewage treatment scale also constantly improve. However, our country sludge processing disposal has not been paid great attention to and has aroused many people's attention. The "12th Five Year Plan" also on the sludge treatment and disposal proposed more stringent requirements, the sludge treatment and disposal technology road map obtained more and more attention and research, sludge treatment disposal management system is becoming perfect, sludge treatment and disposal industry to development.
   At present, according to the scale of sewage treatment in our country, the basic situation of the economic situation of other countries, sludge disposal methods used in China mainly large sludge incineration, landfill and recycling after sludge treatment sludge. In the premise of a country to promote building a harmonious ecological environment and the sustainable development of the environment and resources of sludge treatment and disposal to get some attention. In China's sewage treatment in industrial waste water treatment accounts for a large proportion in city sewage treatment in our country. The heavy metal will transfer in the process, also give the method to bring a lot of difficult problems. Through the brief analysis of heavy metal pollution in city sewage and, on different forms of heavy metals in sludge and processing methods are discussed: in order to reduce the heavy metals pollution control from the source, contents of heavy metals in sludge degradation The sewage treatment plant is mainly from the following aspects to consider:
   1. owing to the great changes of heavy metal elements in different stages of the waste water treatment of the existence of the form and content, the sewage treatment plant should be according to the accepted characteristics of sewage optimization of waste water treatment process and control of heavy metals in the sludge existing form, to the maximum extent in stable form is fixed.
  2. to strengthen the sewage treatment plant sludge monitoring, monitoring, according to the content of heavy metals in the sludge and the classification of the choice of fixed, leaching and other suitable disposal methods
   3. the existing control standards only in farming, forestry, back provisions with the concentration of heavy metals in the sludge, for the reuse of sludge application rate there is no control standard. Should speed up and our country to adapt to the sludge reuse of fertilizer formulation, avoid sludge return with the heavy metal in the soil of long-term accumulation, resulting in secondary pollution.
   Sewage treatment plant from the above three points of will from the source, process, future development and control the whole process of heavy metals in sewage sludge, but also on the sludge agricultural reuse more secure future of sludge treatment and disposal way. Starting from these three aspects, sewage treatment plant of heavy metals will reduce emissions of external environment, reduce the sludge to the environment caused by pollution risk. Therefore, these three kinds of thinking is worth the sewage treatment plant for further scrutiny and promotion. 

：Solution to heavy metal in sludge---add passivator ：Analysis of sludge disposal trend