According to E20 Institute survey shows that, in the end of 2015, China has 607.6 million rural population, more than 2.7 million distributed in natural villages, the annual generated polluted water has amounted to about 10 billion tons. Because the village polluted water treatment facilities has the problems of ubiquitous network construction imperfect and low levels, so the rural polluted water treatment rate is still less than 10%, which means that there are still a large number of untreated polluted water random emissions. When you walk through the village enough, you will find that most of the village even has no garbage, let alone what the polluted water treatment facilities; moreover, most of the villagers believe that it is enough to discharge the polluted water and other rubbishes directly into the river and just flow them away, no more action is excess? Furthermore, this concept is widespread in the village areas. Thus, compared to the current more than 90 percent of urban polluted water treatment rate, the countryside polluted water treatment works has a long way to go; it not only requires the government pay attention to it, and strengthen the construction of infrastructure, but also, the vast and most long-term project is to deeply root the environmental protection concept in the hearts of every citizen.

Column on behalf of the processing capacity (unit: cubic meters/day), line graph on behalf of the number of plant

 

Experiments using photocatalyst under light conditions, to carry out photocatalytic degradation of the life wastewater, and found that due to the COD concentration domestic polluted water are low, therefore, nano photocatalyst is more suitable for processing. Tungsten trioxide photocatalyst has been shown in using for degrading organic pollutants, and play a good effect, include: degradation of pesticides, bleaching treatment, water purification and so on. Furthermore, as a catalyst, the tungsten trioxide photocatalyst itself is not consumed, and can be long-term viability.

 

The crystal structure of the tungsten trioxide is monoclinic, the photocatalytic activity caused in this state has a good effect on the responsive of visible light, and being a good performance of the photocatalyst. In particular, nano tungsten trioxide because of its large specific surface area, the surface effect is remarkable, is a good catalyst, either can be suggested as the primary catalyst, but also as the co-catalyst, and has a high selectivity on the reaction.