Horizontal underflow constructed wetland capable of strengthening denitrification at low temperature

Abstract

The invention relates to a horizontal underflow constructed wetland capable of strengthening denitrification at a low temperature. The constructed wetland consists of a water distribution region, a filling region, an aeration device, a water collecting region and wetland plants, wherein large-grain detritus is positioned in the water distribution region and the water collecting region; the filling region is arranged between the water distribution region and the water collecting region; medium-grain detritus, medium-grain zeolite and fine-grain detritus are positioned in the filling region sequentially; and aeration pipes are laid on the bottom layer of a zeolite segment and the aeration quantity is adjustable. Sewage is subjected to pretreatment, so that suspended matters and part of pollutant are removed, and then the sewage is subjected to constructed wetland purification treatment. The horizontal underflow constructed wetland can greatly improve the dissolved oxygen concentration of the sewage and the ammonia nitrogen adsorption capacity of regenerated zeolite in the horizontal underflow constructed wetland and can maintain high-efficiency and stable nitrogen removal rate of a system.

Description

technical field [0001] The invention relates to a sewage treatment artificial wetland, specifically a horizontal subsurface flow artificial wetland with low temperature enhanced denitrification, and a horizontal subsurface flow artificial wetland sewage treatment technology that improves the denitrification efficiency by adding an adjustable aeration device. Background technique [0002] Constructed wetland sewage treatment technology is a kind of sewage ecological treatment technology that emerged in the 1970s. It has the advantages of low investment, low operating cost, convenient management, and no secondary pollution. It has been successfully used in domestic sewage and rural point sources in recent years. and non-point source pollution, storm runoff, and lake eutrophication, and achieved remarkable results. [0003] According to the water flow mode, constructed wetlands can be divided into: free surface flow constructed wetlands (SFW), horizontal subsurface flow constru...

AI Technical Summary

Problems solved by technology

Existing studies have shown that the oxygen supplied by plants is far from meeting the oxygen demand in constructed wetlands, and the non-rhizosphere area of ​​plants in wetlands is generally in an anoxic state; while the oxygen carried in the water is mainly consumed at the front end of constructed wetlands. Due to the removal of COD, it is difficult to meet the needs of subsequent ammonia nitrogen nitrification

Two: Zeolite matrix is ​​easy to absorb and saturate, and regeneration is difficult

However, the lack of dissolved oxygen in the wetland limits the nitrification of nitrifying bacteria, making the in-situ regeneration rate of zeolite lower than 50%.

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