Recycling of domestic sewage

Recycling of domestic sewage

With the rise of environmental protection awareness, friendly environment and co-prosperity with the natural environment have become an important consideration factor in national development. Because the traditional water resources development methods such as the construction of reservoirs, river weirs, trans-regional water diversion, etc., because the development is extremely difficult, in recent years, the development of new water resources to supplement the traditional water resources.

Waste water recycling is a part of the development of emerging water resources at this stage, and the recycling and utilization of domestic sewage is that the domestic sewage is treated by sewage treatment facilities, and the discharged water passes through the water recycling facilities, or the domestic sewage directly enters the water recycling facilities for treatment. Supply water or groundwater recharge to restricted domestic, industrial, agricultural, environmental landscape, etc. by means of water distribution system.

The form of reclaimed water

The first type of domestic sewage reuse model is based on the discharge water of the regional sewage treatment plant as the water source, and after treatment, the reclaimed water distribution system is supplied to the users in the region for use or for other purposes. Most of the domestic sewage in general cities has been incorporated into the sewage system, and water recycling facilities can collect and treat the effluent from sewage treatment plants or sewage systems until they meet the quality standards of recycled water, and then supply it to household users through the water distribution system, or other uses such as industrial, agricultural, environmental landscape water and groundwater recharge. Therefore, the recycled water distribution system uniformly distributes the amount of recycled water, which is used as a water distribution control for special or emergency purposes, and can allocate a larger amount of water to avoid the waste of tap water.

The second type of model is that in areas where public sewerage has not been reached, the domestic sewage of building users is treated by their own sewage treatment facilities, then treated by water recycling facilities, and returned to users through reclaimed water distribution systems for use as secondary domestic water, such as watering and flushing. In addition, the dual water supply system composed of recycled water supply facilities and tap water supply facilities, when the quality of recycled water does not meet the standard of use or the amount of water is insufficient, tap water can be replaced or supplemented to the recycled water supply system.

The use of reclaimed water

1. Use of reclaimed water

Recycled water is mainly used for household purposes such as toilet flushing, floor cleaning, car washing and other uses not in direct contact with the human body. In order to avoid confusion with tap water, it is necessary to set up an independent recycled water distribution system, including water distribution pipelines and pools, and there should be anti-misconnection measures. Health and water quality safety issues should be considered in use, and users should be educated about proper maintenance. And prevent improper contact and use.

2. Industrial use

The water quality requirements of industrial water use vary according to industry and use, and it is generally recommended to mainly use cooling water, process water and boiler water.

3. Agricultural use

Reclaimed water for agricultural irrigation is mainly used for non-food crops, and the demand for agricultural irrigation, quality of reclaimed water and human safety measures should be considered when used.

4. Environmental landscape water

Reclaimed water utilization system has "direct water supply" and "indirect water supply" two ways, "direct water supply" refers to direct pressure use, suitable for special purposes, such as landscape watering, fire water and so on; "Indirect water supply" is the use of recycled water in tanks (towers), using gravity or free flow for reuse, such as street cleaning, park green space watering, etc.

In the environmental conservation part, renewable water conservancy can be used in wetlands, which can not only enhance the function of wetlands and improve wetland ecology, but also replenish the base flow of rivers and rivers, improve the habitat of animals and plants and the beauty of the environment.

5. Groundwater recharge

Groundwater recharge can store reclaimed water in underground aquifers and then pump it out for agricultural or other water sources when needed, which can slow down formation subsidence and prevent seawater intrusion.