Water mainly refers to the life and the part of the industrial water after a certain process, back to used to agricultural irrigation on the water quality requirement is not high, municipal gardening, car washing, building internal flushing water, landscape water and industrial cooling water, etc, due to its between water (water) and water (water), so called water .
Water reuse, on the one hand, open the second water source of urban water supply, can greatly reduce the consumption of water (water), on the other hand to a certain extent, solve the water (sewage) of water pollution, to protect water source, the action of water.
When solving the problem of water shortage in the world, the first choice for water reuse is the reliable and reusable second water source, which has always been the focus of research.
In foreign countries, the water reuse has been implemented for a long time, and the recycling scale is large, showing obvious economic benefits, and urban sewage has been opened up as the second fresh water resource.
America started very early water reuse, so although the United States since the early 1970 s, the total water consumption has increased 1.4 times, but always take water actually decreased, water used to make America's industrial and agricultural country has made outstanding achievements in the utilization of water resources.
Also, the recycle of Israel has also become a world leader: 42% recycled water for irrigation, 30% recharge underground, recharge underground reclaimed water to take out to the pipeline network system, to the south, the southern region and even use it as a source of drinking water.
Our country has also realized the importance of water reuse and urgency, in recent years, the focus of the urban water reuse, has focused on a large proportion of industrial wastewater, the industrial wastewater back to powerusageeffectiveness has reached more than 70%.
The technique of water reuse is divided into three stages: pretreatment, central processing and post-processing.
The core is the central processing stage, which is used to remove the organic matter of colloidal and dissolved state in water, and further reduce the content of suspended solids.
This phase of processing method according to deal with different water quality, recycle use of different, and the use of the processing method and technology of the different, mainly for flocculation method, biological treatment and membrane treatment method.
At present, the biggest problem facing the water reuse is a weak consciousness of water reuse and water reuse system the imperfection of the planning, construction and operation of water facilities and there are still many problems, has affected the water reuse technology promotion