Sludge treatment has become a problem

As the urban infrastructure continues to expand, every year the construction mud blowout, and how to deal with a large number of sludge and mud has become a problem.

Due to the lack of effective scientific and reasonable disposition, A large number of construction mud exist secretly illegally discharge, causing water pollution, river silting and other environmental problems. The traditional disposal methods of silt are accumulation and landfill, so there are many disadvantages and future problems, and the transportation cost is high and the receiving sites are limited.




Especially the subway shield mud is different from the general waste, high water content, leaks often occur during transit. To the designated residue temporary receiving point, silt accumulation height is limited, the site is limited, can not meet the demand, a large area of silt piling up, if not dealt with in time, there are still very big security risks. And sludge composition is very complex, in addition to stacking problems, if containing harmful substances, there will be secondary pollution.

At present, there are two main ways to utilize the sludge, namely, land utilization or converted to building materials. The land utilization is directly used for sludge landfill, it is required for sludge properties; resource utilization by physical and chemical methods for sludge solidification treatment, and the treated sludge used as filling materials and building materials etc.. Chemical solidification is now more commonly used, generally using inorganic materials, more environmentally friendly.

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