Reading guidance：With the rapid development of economy, frequent pollution event and low environmental quality drive the start-up of pollution control work. Compared with the disposal cost for sludge, the cost for disp

     With the rapid development of economy, frequent pollution event and low environmental quality drive the start-up of pollution control work. Compared with the disposal cost for sludge, the cost for disposing sewage is lower. Sewage disposal is faster than sludge disposal. Therefore, sewage disposal plants and local government prefer to choose disposing sewage. Owing to rapid urbanization and industrial development in our country, the scale of sewage disposal plants becomes bigger and bigger and the production of sewage is getting more and more. Without effective disposal, sludge may eliminate environmental benefits led by sewage disposal and cause secondary pollution. What’s more, pollution caused by sludge may threaten the health of environment and human. At present, sludge disposal market is in chaos. No matter in sludge disposal technical road, management mechanism or market mechanism are in chaos, which brings much difficulties to sludge disposal and project establishment.
    As shown at some evaluated data, the sludge discharge amount in 2004 of sewage disposal plants reaches to 1300000 tons. Meanwhile, after the year of 2004, the production amount of sludge increases by 10% annually. Especially, sludge disposal problem in high level urbanization cities and areas is very severe. According to data of that moment, if municipal sewage gets completely disposed, about 8400000-ton sludge will be produced. This production amount will account for 3.2% of total solid wastes. At present, among main disposal methods, agricultural use accounts for about 44.8%; land landfill accounts for about 31%; other disposal methods account for about 10.5%; no-disposal part accounts for about 13.7%. Due to disposal data mentioned above getting from certain analysis, these data hold some variability. Meanwhile, as presented in relevant data, the investment for sludge disposal will accounts for 20% to 50% of total investment in sewage plants; thus, it can be seen the reason why sludge disposal lags behind severely.
     Because sludge disposal and sewage disposal don’t synchronization, sludge disposal problem is highlighted in big cities. In early establishment of sewage disposal plants, owing to lack of supervision link, sludge disposal sewage disposal are always separated. In order to pursue disposal efficiency, simplify sludge disposal process. Some even don’t establish sludge disposal process. At the same time, money consumed in sludge disposal accounts for large proportion of total cost in sewage disposal plants. As a result, in order to save cost, partial disposal plants prefer to leave sludge disposal system alone. What’s more, some disposal plants deliver sludge which hasn’t been disposed out casually, easily landfill or pile up. Therefore, there are sludge siege phenomena in many big cities and these phenomena gradually spread to small cities. Thus, unsafe hidden danger is caused to our environment.
     At present, owing to frequent pollution events, sludge disposal problems are paid more and more attention by society and our government. Sludge disposal work is emphasized gradually. However, before 2003, the focus of sludge disposal in our country stays on technical layer. After 2003, our government starts to make plans to municipal sludge disposal. Also, carry out comprehensive certification for our technology of sludge disposal, such as following cities: Beijing sludge disposal plans hasn’t passed approval, land utilization will be its main disposal method; according to analysis of situations in different sewage plants, shanghai adopts decentralization, economizing and technical diversity to face with special situations; Guangzhou adopts dumping methods at present. It will use sludge for agricultural fertilizer as a long-term plan; Tianjin plans to establish 3 sludge disposal plants and adopts sludge digestion power generation technology. But there is no final disposal methods for sludge; Shenzhen has finished special planning and plans to adopt heat drying with incineration technology.
 

：Three unification should be achieved in sludge disposal industry ：Development situation of sludge disposal industry in china