Study On The Phytoremediation And Recycling Of Livestock Wastewater

The intensive livestock-producing industry in China had recently beenbooming promptly, which had brought about severe pollution by emittinglivestock wastewater directly into the immediate environment. This paperintroduced the processing and existent problems of the domestic andinternational livestock wastewater treatment at present. The actuality ofenvironmental problems caused by livestock husbandry was discussed andthe relation-ship between husbandry and sustainable development wasremarked on. From the point of ecosystem, phytoremediation was adopted tothe livestock wastewater treatment in this paper. This can deal with livestockwastewater harmlessly and make use of the nutrient resources.With much experiment, the text sieved a series of plants species suitablefor different season and different density wastewater. Futher reseach wascarried on to study the removal efficiency of these plants. The result showedthat different sewage density, different cultivation method, different plantspecies removed different pollutant at diverse speeds. Plants showed greatremoval efficiency of TP sieved in the experiment were Ipomoea aquatica,Spiked Loosestrlfe, Common Duckweed, Yellowflag Iris, Annual Ryegrass.Plants showed great removal efficiency of NH3-N sieved in the experimentwere Eichhornia crassipes, Alligator Alternanthera, Ipomoea aquatica, AnnualRyegrass. The experiment discovered that Ipomoea aquatica grew quickly inwarm season. It was not only a green animal feed, but also a natural vegetable.In the meantime Ipomoea aquatica had a long growth period, during its lifetimeit can be harvested for several times and avoided the again and again planttrouble. Annual Ryegrass was also a green animal feed, and it could groweasily in cold season. The grass was a good feed with enough nourishment forlivestock animals. So Ipomoea aquatica and Annual Ryegrass aquicultured inpromper season could purify the livestock efficiently. The harvested plant couldbe a useful animal feed. This action made full use of the various resourcesesin the sewage.According to the experiment results, this text discussed the consruction ofthe phytoremediation sysyterm. Important influence factors were consideredand design methods were analyzed. There were lots of factors to be regardedin the phytoremediation sysyterm engineering design. The design may be dissimilarity under different time and location.With the above study, the text designed two phytoremediation sysytermsfor livestock wastewater treatment. The two projects had already finished theconstruction. Parts of the projects were in use.