| The technology of wastewater treatment with Artificial wetland had the characteristics of high efficiency and low consumption. In recent years, the technology was concerned with municipal wastewater treatment and non-point source pollution control. Utilizing the wetland technology could enhance the use of water resources to better protect the water environment and also was consistent with the concept of sustainable development.So it was inevitable choice in low-carbon cycle economic development.In this paper, the soil as a substrate, Lolium multiflorm and Pennisetum purpureum Schumach for the vegetation, we studied the both grasses and artificial wetland whose effect and mechanism about wastewater treatment in stock farm according to the experiment simulating the intermittent nature of constructed wetland purification system and combinating wetland field.The results by Simulating intermittent wetland purification system showed that ryegrass in Winter and spring can adapt to grow well in the intermittent sewage influent concentrations of up to TN 816.8±125.1 mg·L-1, NH4+-N 443.6±97.9mg·L-1, NO3--N 141.5±51.7 mg·L-1, TP42.9±11.2 mg·L-1, pH 8.0±0.5, COD 2468.2±237.4 mg·L-1, The removal rate to ammonium nitrogen was 75.9～88.3%,to nitrate nitrogen was an average of 69.3%, to total nitrogen was 74.5～83.1%, to total phosphorous was 90% over,to COD was 60.5～76.8% and all the treatment effect was negatively correlated with the wastewater concentration.under the conditions of the purification system at different concentrations and the hydraulic retention time of 8 days.This experiment indicated that ryegrass on the absorption of nitrogen and phosphorous in wastewater to their contribution purification rate were 20.03% and 20.42%.The Pennisetum purpureum Schumach in Summer and Autumn could also grow well in intermittent sewage treatment. All the index of removal effect was like ryegrass in winter and spring,but better than ryegrass.Under the condition of the hydraulic retention time of 8 day,the removal rate to ammonium nitrogen was 91.2～94.9.%,to nitrate nitrogen was an average of 86.9～90.3%, to total nitrogen was 91.2～92.6%, to total phosphorous was 93.1～92.6%,to COD was 66.8～76.3%. The Pennisetum purpureum Schumach on the absorption of nitrogen and phosphorous in wastewater to their contribution purification rate were 25.12% and 31.20%.The result of artifical wetland combined field showed that each index about sewage removal was similar to the summer and autumn with the spring and winter. the pollution index could reduce by 80% under the condition of the hydraulic retention time of 4 days and may improve pollution effect through appropriate extend the hydraulic retention time.When the sewage flowed through Subsurface-like artifal wetland,it declined mostly by 77.0%.Utilizing the nutrient in sewage to plant Pennisetum purpureum Schumach, maize and ryegrass, which could save nearly 3 million fertilizer each year;.These harvested grasses could cost savings to 65,000 yuan.over for dairy farms every year converted by the local purchase price,...
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