Method for controlling bottom mud siltation after dredge

Abstract

The invention discloses a method for controlling bottom mud siltation after dredge, belonging to the technical field of ecological restoration of polluted water bodies. With zeolite covering and bentonic organism sludge reduction function as core, the method disclosed by the invention is used for controlling the release of source pollution in the bottom mud by throwing zeolite to perfect the self-purification function of the water body and reduce the deposit rate of the bottom mud; the bentonic organism ingests and mineralizes the bottom mud to reduce the newly deposited bottom mud, and self-regeneration of biosorption and degradation effects of zeolite on the bottom mud pollutants is realized at the same time. Only one zeolite throwing device is added on a dredger and bentonic organism is placed on the zeolite, thereby having the advantages of being simple to operate, low in operation cost, low in energy consumption, ecological, environment-friendly, long in control effect effectiveness, and convenient to execute and apply in large scale.

Description

Technical field [0001] The invention relates to a method for controlling back siltation of sediment after dredging; it belongs to the technical field of ecological restoration of polluted water bodies. Background technique [0002] Sediment dredging is one of the important measures for ecological restoration of polluted water bodies because it can realize the complete transfer of polluted sediments and the utilization of ex-situ resources. In developed countries such as Europe, America and Japan, sediment dredging has been widely promoted and applied. my country has also implemented sediment dredging projects in the comprehensive treatment of a series of polluted water bodies such as Taihu Lake, Dianchi Lake, Qinhuai River and Suzhou Creek. However, the current polluted water bodies that use dredging for ecological restoration have obvious back-silting phenomenon of sediment. The main reasons for the back-siltation phenomenon are the input of external pollution and the release ...

AI Technical Summary

Problems solved by technology

[0006] 1. Due to the limitations of the existing dredging technology, equipment and technology, there are unavoidable phenomena of missed excavation, under-excavation and substantial disturbance of the sediment during the dredging process. The mud will continue to release a large amount of pollutants to the water body, resulting in the degradation or even loss of the self-purification function of the water body, thereby accelerating the back-silting;

[0007] 2. The bottom mud is removed by dredging activities, and the benthic organisms and functional microorganisms in the benthic environment are completely lost. Due to the degradation or loss of the ecological functions of the overlying water and the benthic environment, the degradable suspended / glue entering the dredged water body Body pollutants cannot be effectively degraded and will sink into the sediment. At the same time, the mineralization and reduction capacity of the benthic environment to the sediment is severely weakened, and the reduction of the deposited sediment cannot be achieved, which also accelerates the sedimentation process.

[0008] In short, so far, there is no efficient, fast, low-consumption and operable method for controlling sediment back-silting after dredging polluted water bodies at home and abroad, and environmental protection dredging often falls into "dredging-silting-re-dredging-re-silting" vicious circle of

For example, Xi’an’s moat underwent three large-scale dredging treatments in 1983, 1998, and 2004, but the silt was still unable to be completely eradicated, so large-scale dredging had to be carried out again in 2008; Dianchi Lake has been dredged continuously for 13 years since 1998. Annually, remove about 15 million m of sediment 3 , but the thickness of polluted sediment at the entrance of Caohai Lake is still as high as 1.1m or more

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