Physical-chemical-biological combined treatment device and method for acid wastewater

Abstract

The invention relates to a physical-chemical-biological combined treatment device and method for acid wastewater. The treatment device comprises a regulation and storage tank, a nitrogen deoxidization tank, an anaerobic alkaline slow-release neutralization and sedimentation tank, a drop aeration section, a sloping plank sedimentation tank, an anaerobic ecological wetland and a drying tank which communicate with each other in sequence. According to the treatment method, by reasonably controlling the dissolved oxygen content, the water passing mode and the physical primary sludge process of the acid wastewater at different stages, neutralization precipitation, physical sludge removal and long-acting microbial operation of the whole system are realized; long-acting slow release of an alkaline material and stable growth of anaerobic microorganisms are realized, and stable and efficient removal of heavy metals and inorganic salts is ensured; low-power operation and maintenance of the whole system can be realized through a water passing mode; physical primary mud can ensure stable operation of the whole system; and the system has the advantages of simple process, convenience in maintenance, low treatment cost and small occupied area, and the treated wastewater reaches the discharge standard for class-3 water bodies of surface water.

Description

technical field [0001] The invention relates to the field of wastewater treatment after the acidic water in the mined-out space overflows to the surface after the mine is closed, in particular to a combined physical, chemical and biological treatment device and treatment method for acidic wastewater. Background technique [0002] With the increase of resource-exhausted mines in our country, a large number of mines with small output and no safety guarantee have been closed. After the closure of large-scale mines, a series of safety and ecological environment problems have arisen. Among them, the overflowing acidic water from abandoned mines has a huge impact on the surface ecological environment. Mine water spilled after mine closure generally has the characteristics of low pH, high iron, high manganese, and high sulfuric acid. [0003] The existing acid water treatment methods mainly include physical method, chemical method and biological method; among them, physical metho...

AI Technical Summary

Problems solved by technology

However, this patent needs to add a large amount of chemicals to deal with acidic water, which will generate a large amount of mud and easily cause secondary pollution, and the system needs to increase the mixing process, resulting in increased treatment costs

[0006] Patent CN109607971A combines the neutralization method and ecological treatment to treat acidic water. The acidic water is first neutralized by alkaline limestone and periclase, and the treated water enters the aerobic wetland. The treated wastewater meets the surface water class III standard. The above method has the characteristics of low treatment cost and small footprint, but this method requires a minimum hydraulic retention time, resulting in a large system footprint, and no desilting unit is installed, and alkaline materials are prone to failure

[0007] In summary, the current acid mine wastewater treatment process mainly has the disadvantages of large amount of sludge, low treatment efficiency, rapid treatment system failure, poor sulfate removal rate, manual operation and maintenance, and high economic cost.

Images