Papermaking sewage advanced treatment system and method

Abstract

The invention relates to the technical field of sewage treatment, in particular to a papermaking sewage advanced treatment system and method. The system comprises a pretreatment system, an anaerobic treatment system, an aerobic treatment system and an advanced treatment system which are sequentially connected through pipelines from upstream to downstream, and a water outlet of the aerobic treatment system is further connected with a water inlet of the pretreatment system through a pipeline. A part of effluent of the aerobic treatment system flows back to the pretreatment system; the water inlet amount of the anaerobic treatment system can be effectively increased; the inlet water COD and TN concentration of the anaerobic treatment system are reduced; therefore, the water inlet load of theanaerobic treatment system is reduced, it is guaranteed that the anaerobic treatment system is always in the optimal reaction condition, the COD removal rate of the anaerobic treatment system is increased, the treatment pressure of the aerobic treatment system is reduced, and the treatment efficiency of papermaking sewage is improved on the basis of saving the cost.

Description

technical field [0001] The invention relates to the technical field of sewage treatment, in particular to a papermaking sewage advanced treatment system and method. Background technique [0002] Since 2017, my country's waste paper import-related policies have been introduced one after another, and waste paper import control has become more stringent. In July 2017, the State Council issued the "Implementation Plan for Prohibiting the Entry of Foreign Garbage and Promoting the Reform of the Solid Waste Import Management System", which strengthened the management of solid waste imports. In December of the same year, the Ministry of Environmental Protection issued the "Environmental Protection Management Regulations for Imported Waste Paper" and " Restricted imports of solid waste that can be used as raw materials for environmental protection management regulations, regulate the import of waste paper, and at the end of 2018, it will be mentioned that "all imports of solid waste...

AI Technical Summary

Problems solved by technology

The issuance of waste paper import restrictions has brought a huge impact on waste paper and papermaking. The reduction in the amount of imported waste paper has led to a sharp increase in the consumption of domestic waste paper raw materials. Compared with imported waste paper raw materials, domestic waste paper raw materials have a lower yield. , There are many pollutants, so the pollutants in domestic waste paper and papermaking sewage have increased significantly, resulting in a significant increase in the difficulty of sewage treatment and the cost of sewage treatment

[0003] Currently commonly used papermaking wastewater treatment systems include pretreatment systems (i.e. physical treatment methods), anaerobic and aerobic treatment systems (i.e. biochemical treatment methods) and advanced treatment systems (i.e. chemical treatment methods). Drainage from papermaking workshops first enters the pretreatment system , after filtration and natural settlement in the pretreatment system, the pollutants can only be reduced by 10%, and then the sewage enters the anaerobic treatment system. According to the current domestic and foreign anaerobic treatment system design indicators, the chemical oxygen demand of the influent water (COD) has a clear specification requirement, the COD concentration should not be higher than 3500mg / L, too high COD concentration will lead to the rapid death of the biological bacteria in the anaerobic treatment system, causing the entire anaerobic treatment system to collapse

In addition, the total nitrogen (TN) in the papermaking wastewater is mainly treated by the aerobic treatment system, but the aerobic treatment system has a limited ability to deal with the total nitrogen, and the general removal rate is 60%.

[0004] Due to the obvious increase of pollutants in domestic waste paper and papermaking sewage, the cost of the domestic waste paper and papermaking sewage treatment system commonly used at present is significantly increased, and the treated sewage cannot guarantee to meet the drainage standard

Images