Study Of The In Depth Treatment Of Constructed Wetland For Wastewater Treatment Plant Upgradation

With the lack of water resources and increasing environmental pollution; wastewater treatment plant emission standards has been improved. It is a very increasingly concern in deep treatment of wastewater. Constructed wetlands are very vital as a typical eco-processing technology which has characteristics of high efficiency, low investment, low-power, and low-maintenance technology. It can adapt to remove the pollutants of low concentration wastewater and it also can be incorporated to reduce pollutants of the wastewater in maximize extend. In addition, Constructed wetlands have good ecological effects if artificial wetland treatment systems add to conventional biological treatment processes. To some extent, it is not only meet the urban water pollutant discharge standards for sewage treatment plants and quality requirements of reuse water, but also it is useful as restoration of contaminated water. It also has a good environment and economic benefits.In order to investigate artificial wetland effect of deep purification for municipal wastewater treatment plant outlet, screen the appropriate hydraulic load for deep purification of sewage plant effluent matrix, as well as to improve the purification effect and stability of artificial wetlands. Study was carried out for the constructed wetland system of Longwang zui sedimentation tank outlet water for different substrates and different types of the advanced purification effect and influential factors. Then studied the principles of constructed wetlands for degraded organic matter, nitrogen and phosphorus. Finally, proposes some measures of strengthen denitrification.(1) Artificial wetlands for municipal wastewater treatment plant effluent in-depth treatment is feasible.To some extent,artificial wetland system can purification the water of sewage plant outlet in further and control the concentration of certain pollutants, comprehensively improve effluent quality.(2) Advanced treatment wetland model results show that the constructed wetlands have good treatment effect for SS and turbidity, the average removal rates were 85% and 70%; COD removal rate was 30%; TN average removal rate of 20-25%; the average of generally broken bricks and fly ash filler fill wetlands to TP removal rates of up to 70%～75% and 87%; It exists an obvious difference on phosphorus removal effect when the wetland systems were composed with different fillers. Wetlands system which were composed with fly ash brick particles, the treatment effect for TP is much better than other wetland systems which uses shale and gravel. To enhanced the effect for phosphorus removal, Fly ash is a good appropriate filler for artificial wetland.(3) The constructed wetland system have great efficiency for TP, SS and turbidity when hydraulic loading is different, but it is less effective for COD,TN. In different four groups of hydraulic loading, the rate of TP removal is increases when the hydraulic loading decreases of inlet water; and the rate of COD removal like the rate of TP removal which is also shown a downward trend when hydraulic load is increaseing, but the system effluent COD concentration is mess when the hydraulic load changed; the purifying effect of TN have not any change with the hydraulic load change which different from COD and TP.Integrated the purifying effect of constructed wetland for LongWangZui plant sedimentation tank outletwater. it conclude that the best hydraulic load for water-depth treatment is0.07-0.123 m3/(m2.d).(4) Plants are not have great affect for COD and TP. In controlled trials,. Plants can stabilize the purify effect for removaling TN and improve wetland system against for the impaction of pollutant concentrations.