Study On Purification Of Ammonia Nitrogen, COD, Total Nitrogen And Total Phosphorus On Fenhe Sewage By Six Aquatic Plants

Water pollution restricts economic development and harmful to human health, moreover, water pollution has become a global environmental problems. Aquatic plants play an important role in constructed wetland, and comparative researches on different aquatic plants of the absorption of ammonia nitrogen, COD, total nitrogen and total phosphorus was important for purificting sewage. Some aquatic plants can absorb nitrogen, phosphorus and nutrition elements in water, though competitive channels inhibit the reproduction of algae that also absorb nitrogen, phosphorus and other nutrients; furthermore, they can block and condensation of suspended solids, organic polymer in water, reducing the turbidity of the water.The Fenhe sewage from the Taiyuan Section was delt by using six aquatic plants, Chara contraria, Nasturium officinale, Phragmites australis, Polygonum orientale, Cladophora fracta, Potamogeton crispus. The result were summarized as follows:(1) Six kinds of aquatic plants all had certain ability to purify ammonia nitrogen. At the three levels the best ammonia nitrogen purify ability was P. australis, the dilution ratio3:0was25.57%, dilution ratio1.5:1.5was37.44%, dilution ratio2:1was48.94%, C.fracta was worst, the dilution ratio3:0was7.01%, dilution ratio1.5:1.5was13.62%, dilution ratio2:1was16.26%.(2) Six kinds of aquatic plants all had certain ability to purify COD. At the three levels the best COD purify ability was P. australis, the dilution ratio3:0was50.57%, dilution1.5:1.5was60.98%, dilution ratio2:1was63.07%, N. officinale was worst, the dilution ratio3:0was9.31%, dilution ratio1.5:1.5was29.88%, dilution ratio2:1was39.45%.(3) Six kinds of aquatic plants all had certain ability to purify total nitrogen. At the three levels the best total nitrogen purify ability was P. australis, the dilution ratio ratio3:0was66.82%, dilution ratio1.5:1.5was 69.40%, dilution ratio2:1was75.44%, C. contraria was worst, the dilution ratio3:0was10.14%, dilution ratio1.5:1.5was14.11%, dilution ratio2:1was47.73%.(4) Six kinds of aquatic plants all had certain ability to purify total phosphorus. At the three levels the best total phosphorus purify ability P. australis, the dilution ratio3:0was53.15%, dilution ratio1.5:1.5was63.31%, dilution ratio2:1was65.79%, P. crispus was worst, the dilution ratio3:0was14.72%, dilution ratio1.5:1.5was38.46%, dilution ratio2:1was40.90%.(5) At the three levels, each index purification effects were high concentration level<concentration level<low concentration level.Phytoremediation was one of the lower cost, lower power and easier management plants which will improve to resource utilization for sewage and it was one of the technologies to improving the environment of water pollution. Among the six species of plants the best purification effect plant was P. australis, it suggested that P. australis could be used as the preferred purification of sewage.