Analysis of the prospects and constraints factors to China's water
Urban sewage or sewage water refers to the survival of treated water quality scale punishment after the arrival of the affirmative, can be reused in a certain range of non drinking water, the water quality indicators below the drinking water quality scale, higher than the permissible discharged into the ground water discharge standard of sewage.
The original water refers to the choice for reclaimed water source and untreated water, reclaimed water source selection should be based on the original drainage water quality, water, drainage condition and water quality, water quantity to determine the required. Reclaimed water source as usual for survival, living sewage, waste water cooling water etc.. Hospital sewage, sewage and other production due to containing a variety of bacteria, viruses and other harmful substances, factors is more massive, is not suitable for water source.
According to the range from small to large, reclaimed water system can be divided into three kinds, respectively is: single building reclaimed water system, water system and water system in urban area.
Water treatment is growing as the growth of water treatment skills, because handling things for sewage and water treatment, to reach the purpose of recycling, and the related water quality meet the national scale, therefore, the processing technology of water treatment, according to the punishment mechanism of difference can be divided into physical and chemical treatment penalty method, biological treatment method, membrane treatment of punishment law three categories.
In this paper, the tension analysis of our reuse prospect and binding factors, to provide ideas for Chinese water growth.
1 of China's recycling status and Prospects
1.1 present situation of water resources in China
China is a shortage of water resources deficient country, per capita water resources is only the world average per capita amount occupied occupy 1 / 4 volume, and the spatial and temporal distribution imbalance, the development and use of extremely difficult, resulting in many regions and cities of severe water shortage. There are more than 180 urban water shortage in the world more than 300 large and medium-sized city, more than 50 serious water shortage in this, this has restricted our country social economy can be continuous growth in the very great degree.
With 1.2 back water significance
Water is sewage after treatment punishment to water scale after reused water, so you can play a dual purpose water saving and pollution control, has great social benefit and environmental benefit.
(1) to save water
Although compared with tap water, reclaimed water provides the category to be small, but in some areas, water is the best alternative source of tap water. These categories include: agricultural water, industrial water and living of the people and the community of non potable water. The water can increase the total social supply, and supplement and substitution effect of reclaimed water on tap water helps to meet the agricultural and industrial growth and population growth in the demand for water.
(2) the economic benefits
The sewage after treatment for miscellaneous water depth, the whole project is concerned, is undoubtedly to growth allocation of investment, but the water nearby reuse water guarantee, transport distance is short, the elimination of the urban water supply and drainage water, thus reducing the urban water supply and drainage pipe network and processing of engineering load, total investment for the city water supply drainage configuration is the economy, the domestic and foreign practice proves that opens the regeneration wastewater source, the economy is lower than other water open.
(3) the environment benefit
China's water resources shortage of tension, and pollution of water resources increasingly tense. In this environment, carry out the water treatment, advocates have enormous environmental benefits of sewage recovery. After depth treated wastewater reuse for industrial, municipal, agricultural and other areas, wanton growth of sewage resources, making it the second reliable water resources, both to alleviate the problem of water resources shortage, and eliminated the sewage emissions, deal with relieving the problem of environmental pollution has the huge significance. It can not only eliminate the exploitation quantity of groundwater, also is advantageous to reduce the natural surface water opening strength, ease the water shortage problem in natural rivers, disconnection, thus alleviate other environmental problems caused by river water shortage.