Research On Waterscape Functional Rehabilitation Technology & Evaluation On Environmental Benefits

The water body in urban areas, such as lakes, artificial lakes and ring-city rivers, becomes a key part of cities' scenery, playing a role of beautifying surroundings and attracting tourists. Most of the urban water bodies are combined with the local human and natural landscapes, and with a deep cultural deposit as a result. They are a key element comprising of urban landscape, and thus get the reputation as a city's pearl. However, with the speed of China's economic development surpassing that of environmental protection industry and people's concept, the landscape water bodies bear increasingly heavy burden of urban development and population. With its own characteristics of low ability in flowing and self-cleaning, the input pollutants surpass the water body's max loading ability. At present, most of the landscape water bodies' quality in China is getting worse, with the major problem as eutrophication caused by the large quantity of N and P pollutants.The thesis selects such two techniques as contact oxidation and biological aerated filter, through research on the mass transfer about reactor system, to carry on the test of landscape water body quality recovering. The filter selection test, which has the most influence on the system of mass transfer, is carried on first, and the clean water oxygen test shows that partial filters candouble the oxygen's using efficiency in the aerated system.The contrast experiment was carried on with the landscape water in the Chaoyang Park in City of Changchun as objective and by means of the two techniques above. The experiment consists of such phrases as starting, searching for the best running conditions, running in the rainy season and running in low temperature in winter. The result shows that the two techniques decrease the COD, NH3-N and TP respectively by 40%, 85% and 45% in rainy season, and the effluent quality gets better than standard, contact oxidation, which is developed by our country's own effort, plays a better role in disposing landscape water micro pollution than the biological aerated filter. The disposing efficiency of the two techniques decreases with the temperature getting lower in the first half phase in winter but gets steady in the latter half phase. Contact oxidation shows its competitive advantage. This test is the first research in China on the contrast of the two techniques above, and the data results have certain reference value to the other fields of wastewater disposal.The research was carried on the contrast of such three disposal means as ground water supplying, middle water supply and water circulating, with the South Lake in Changchun as objective and from the aspects of environment efficiency and influence. The results show that water circulation disposal has advantage in technique and economy. Its influence to environment and society is least. Although the disposal station is relatively close to the landscape water body, the bad influence can be minimized by taking measures as selecting a reasonable site, beautifying design and strict management.