Study On Optimized Parameters Of Operation Condition In Rural Sewage By Subsurface Flow Constructed Wetland

With the economic development of rural areas and the improvement of farmers’ living standards, the increase emission of rural sewage make environment further deteriorated. Therefore, study on the treatment technology of rural sewage is particularly important, it have positive role in controlling environmental pollution of rural sewage and slowing down the eutrophication of water bodies.On the basis of consulting a large number literature and surveying the rural sewage treatment units of Lake chaohu, four kins of matrix combination artificial wetlands were constructed. Combining mechanism analysis and simulation test, the study were conducted on structural factors (wetlands matrix combination), operation factors (reflux ratio aeration than), environmental biological factors (algae), and optimal parameters, through the research of pollutant concentration internal variation, the decontamination performance of the various the matrix was revealed.The study indicated that, for decontamination ability of the combination matrix, A1combination (zeolite/biological taoli/steel slag/anthracite)is optimal; Although removal efficiencies of the brown earth is good, but it is very easy to plug and not suitable as artificial wetland packing; for the wetlands kinds, when upward flow and downward flow have the same water stage, the treatment effect of upward flow wetland is good; for operation factors,1and7of reflux ratio and gas-water ratio respectively is the best, if continuing to increase both, the treatment effect will cut down; Algae can improve internal biological structure and dissolved oxygen status, so it can enhance degradation ability of pollution; The test results of pollutant concentration internal variation show that, along the flow direction, organic matter, nitrogen and phosphorus gradually reduce, removal rate of each layer of wetland is affected by matrix combination and structure, comprehensive removal effect of layers of matrix, the decontamination capacity of single matrix followed by:anthracite coal>slag>zeolite>bio-ceramic>activated carbon> gravel.