Reading guidance：612 sewage disposal plants are establishedalong with the process of industrialization and people environmental protection consciousness enhancement, Chinas sewage treatment industry is developing rapid

     612 sewage disposal plants are established along with the process of industrialization and people environmental protection consciousness enhancement, China's sewage treatment industry is developing rapidly. In 2003, the national total of urban sewage treatment plants, sewage treatment capacity of 148 million tons; by the end of 2011, the sewage treatment plant increased to 3 135 bridges, sewage treatment capacity is high up to 496 million tons of municipal sewage sludge for sewage treatment inevitable product, its production will continue to grow at the same time, sludge due to bearing with water nearly half of the organic pollutants, heavy metal pollutants and pathogenic bacteria and pathogenic bacteria is relatively rich, sludge disposal will become our country a more prominent environmental problems.
   The content of heavy metals in the sludge into the city, the soil environment is difficult to biodegrade, but easily through the food chain enrichment of organisms, pollution of heavy metals in sludge is one of the important sources of heavy metal pollution in soil, and has become one of the main restrictive factors of sludge beneficial use, so the behavior of heavy metals and the migration and transformation of city sludge has become a hot research topic in Environmental Science and other fields. At present for the content of heavy metals in sludge China city environment investigation results showed that the content of heavy metals in sludge from the city of industry type, the nature of the city, sewage treatment and sewage source is different and there is a big difference, the contents of heavy metals in city industrial waste water sludge source the sewage sludge is higher than main. But compared with the previous, the overall trend of the heavy metal content in sludge research. Results have not been determined, there is a study showed that the heavy metal content of urban sludge overall showed a downward trend, but there are also some studies show that some of the heavy metal content is on the rise.
    The coastal city sludge research study found that the different distribution of heavy metal pollution of coastal city sludge, the average content of 7 kinds of heavy metals in the order of Cr > Zn > Cu > Pb > as > Hg > cd. > and < plant pollutant discharge standard of urban sewage treatment, sewage treatment plant sludge of heavy metal pollution serious pollution elements as Cr, Cu and as. are currently in China's coastal city of Zn in sludge than before significantly reduced, Pb, Hg and Cd content had no obvious change, but Cr, Cu, as were significantly increased. The degree of heavy metal pollution and sewage source and the area where the relevant city sludge in sewage sludge from the city. Industrial waste water in Zn, the average content of Cu and Hg were mainly sewage sludge; sewage treatment plant in Guangzhou city sludge in Cr, Pb, as, Hg and Cd were higher than those of Shanghai and Dalian in China. Beyond < urban sewage treatment plant pollutant discharge standard > sludge agricultural standard limit value of waste water treatment plants accounted for 23% of general survey of sewage treatment plant, most of the sludge of China's coastal cities still using sludge for agricultural use beneficial disposal
    Zhengzhou taida drying equipment co,. Ltd is a professional company which mainly specializes in sludge plan design, sludge disposal construction and sludge system operation. The company has specialized sludge treatment technology team, can provide a more reasonable processing solutions for the owners of sludge treatment, welcome to our company to discuss cooperation, we will be dedicated to solve the problem of sludge treatment for you.
 
 

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