Mode And Mechanism Of Substrate Clogging Remove In Wavy Subsurface-flow Constructed Wetlands

As a green new way to wastewater treatment technology, constructed wetland hasbeen concerned widely. But according the wetlands in engineering practice, we found thatit has been clogging with different degrees. Therefore, it is very necessary and urgent tostudy the clogging mechanism in constructed wetland and find appropriatecountermeasures on this basis. Aiming at the substrate clogging problem in constructedwetland chich often encountered in operation, two methods were studied in this paper. Thestudy aims at defining the mechanism of substrate clogging of constructed wetland andoptimizing operation parameters to prevent substrate clogging, as well as finding feasiblemethod for solving substrate clogging problem. This paper can get following conclusionsthrough the research:(1) Alternate operation could delay the occurs of wetlands. Alternate operationincrease the oxygen between filter material, to reduce the accumulated suspended solids.In this study, the accumulated suspended solids of two wetlands decreased by20%and21%respectively after alternate operation, which volatile suspended solids accounted theproportion of volatile suspended solids in which were80%and89%respectively.(2) Seen from the result, it was best to1#wetland was the way in alternate operationwith half water, and the infiltration rate of surface layer was back to475%, and it was bestto2#was the way in alternate operation with full water, the infiltration rate of surfacelayer was back to479%.(3) Exchange the water-inlet operation can relieve clogging effectively. In the twoprocess of relieving clogging, the recovery rate of surface layer of3#wetland in were1866%,35%and354%,161%, the rate of4#wetland were195%,1059%and248%,32%.(4) Aeration can make the distribution of accumulated particles more uniform in thedirection of influence. The rate of suspended particles in surface layer and subsurfacelayer were4.71and4.77in room A and B respectively, and which in4#wetland were3.46and2.87. It indicated that some suspended particles transfer to the lower layer withaeration. (5) The content of inorganic matter in4#was much more than3#, the rate ofNVSS/VSS of surface and subsurface layer were1.44,2.83and1.47,2.84respectively,4#were1.11,1.65and0.79,0.64.