Study On The Development And Experiment Of New Package Bioscreen

Water pollution is becoming a main factor causing short water supply. Now water eutrophication is a worldwide phenomenon and becomes one of the most tough issues in environmental remediation for water pollution. Understanding the mechanisms of eutrophication of water body and develop feasible remediation technology is the frontier and hot research field in plant nutrition and environmental ecology. The purposes of this study are to choose a kind of aquatic plant, which is one core part in the bioscreen, to develop the regulation of choosing aquatic plant; to study the effects of bioscreen composed of aquatic plant and package on the Liwa river in the low temperature season; to study the effects of benthic mollusks on the Liwa river; to compare the effects of bioscreen composed of different packages on the Liwa river in the low temperature season.The experimental results of choosing aquatic plant showed the bioscreen composed of package and aquatic plant had obvious effect on the eutrophication water body. The average removal efficiency of TN is 41.35%, 39.42% and 43.49%, and the average removal efficiency of TP is 34.44%, 35.39% and 47.39% for the Oenanthe javanica system, Eichhornia crassipes system and Alternanthera philoxeroides system respectively. When aquatic plants didn't grow well, however, the removal efficiency decreased. The results also showed that the package, comparing with the aquatic plant, played an more important role in the treatment process. At last, the guideline about choosing aquatic plant, which includes adapting. environment, tough roots, great purifying ability, long life circle, easy management and low price, was suggested,The experiment, in the low temperature season, showed the water quality kept the good level caused by the microorganism when the aquatic plants grew bad. So it was suggested that the aquatic plants could be removed from the system, according to water quality, when they grew bad in the low temperature season. The treatment performance of 10h (HRT) was better than that of 6h(HRT). Whether oxidation or not, the changes, however, was not obvious. The running conditions of HRT<6h and no oxidation were suggested in the same situation to decrease the cost of building and operation.Benthic mollusks had effects on the treatment of eutropfication water according to the experiment and anodontawoodianaelliptica was better than snail. The optimal quantities of them are 35/m~~2-70/m~~2 (snail) and 3 /m~2-7 /m~2 (aodontawoodianaelliptica) and the optimal running conditions are HRT=3d and oxidation. The result of multi-linear regress analysis...