Industrial wastewater treatment technology

1.5 Sewage recycling Energy saving and environmental protection is the theme of China's current sustainable development, if the use of water treatment technology to recycle industrial waste water to other ways will save a considerable part of the water consumption, bring economic benefits at the same time to save China's water resources. The recycling of sewage has achieved remarkable results in foreign countries, and more and more enterprises are applying the treated sewage to other fields. With the development of sewage treatment technology, the feasibility of industrial sewage as a secondary energy is getting higher and higher, the development of water treatment technology has promoted the production efficiency of enterprises, and the recycling of sewage has been paid more and more attention by enterprises. Conforming to the national policy and conforming to the people is the fundamental of industrial development.

1.6 Application after sewage treatment The demand for water in industrial production is different in different sections. Under the requirement of ensuring safe production, the workshop wastewater can be reasonably classified according to the demand standard by using sewage treatment technology to form the next level of workshop water. In the workshop through the sewage diversion water (including circulating cooling water, boiler water, overflow water, auxiliary water and cleaning water, etc.), ground collection of rainwater, living area water and other less polluted wastewater, after preliminary treatment can be widely used in brick factories, cement factories, mines, construction and other factories. BOD5 and COD indicators can be reduced to identify the biological and chemical oxygen demand consumed by the complete decomposition of organic substances in sewage to form water and carbon dioxide. The higher the content of unsaturated organic matter and inorganic matter in wastewater, the greater the values of BOD5 and COD. BOD5 /C index is an important indicator of the biodegradability of sewage, and it is usually stipulated that BOD /COD > 0.45 has the best biochemical effect. The sewage is mainly organic pollution, and the biochemical effect is the best when BOD /COD= 0.58. BOD5/T index is an important indicator of biological nitrogen removal requirements, because the hydrogen donor for denitrification in the biological nitrogen removal system mainly comes from the substrate in sewage, and the greater the ratio, the more obvious the nitrogen removal effect. BOD5 /TP index is an important reference to the production water consumption of biological phosphorus removal requirements, so that the problem of water shortage can be alleviated. Industrial sewage contains a large amount of salt, unreacted raw materials and valuable intermediate products. Recycling devices are used to process and extract valuable components in sewage, turning waste into treasure and harm into benefit. On the one hand, the cost of raw materials required for production is saved, and on the other hand, the concentration of sewage is reduced. The waste acid and alkali generated in the production process of chemical plants can be applied to the neutralization and regulation of sewage, saving the cost of sewage treatment and creating secondary value by waste treatment.

1.7 Water and stolen discharge industrial parks are big polluters generally far away from urban areas and developed areas, located in relatively remote desert, suburban and other places, stealing sewage behavior is widespread but difficult to be found and punished. With the increase of the state's requirements for special new indicators related to sewage treatment, the cost of sewage treatment and sewage treatment faced by enterprises is getting larger and larger, the increase of tap water, steam and electricity, the increase of industrial production raw material costs and the reduction of enterprise product sales have a certain degree of impact on China's industrial development. More and more enterprises are listed, the competition between peers, and the sluggish international economic situation make the survival and development of enterprises weak. Some areas adopt the "one enterprise one pipe" management model, that is, an enterprise one pipeline first through the enterprise's own sewage treatment station to treat the polluted water to a certain index after centralized collection of standardized sewage treatment plants for centralized treatment.