Subsurface flow wetland device for enhanced nitrogen removal of low-pollution water

Abstract

The invention relates to a subsurface flow constructed wetland device for enhanced nitrogen removal in the technical field of environmental engineering. The device comprises a pretreatment settling tank, a hydraulic drop aeration well and a wetland groove, wherein the wetland groove comprises an aerobic nitrating segment, an inspection well, an anoxic denitrification segment and a water collecting well in the water flow direction; the pretreatment settling tank is used for settling suspended matters to prevent follow-up structures from being blocked; hydraulic drop steps are arranged in the hydraulic drop aeration well to increase the dissolved oxygen concentration; active substrates capable of adsorbing ammonia nitrogen are filled in the aerobic nitrating segment, a perforated aerator pipe is vertically inserted and vascular plants are planted to increase the dissolved oxygen concentration in the packing layer, so that the smooth generation of the nitrification is guaranteed; a secondary water inlet pipe is connected into the inspection well to supplement the carbon source that the denitrification requires; efficient phosphorus removal substrates are filled in the anoxic denitrification segment to generate the denitrification, adsorb and remove phosphorus pollutants; the water collecting well is used for collecting treating water and discharging the water out of the device finally. Compared with the prior art, the device disclosed by the invention has the advantages that nitrogen in sewage is well treated and both the total nitrogen removal rate and the ammonia nitrogen removal rate can be up to more than 80%.

Description

technical field [0001] The invention relates to a device in the technical field of environmental engineering, in particular to a subsurface flow artificial wetland device with enhanced denitrification function. It can be used for enhanced denitrification of low-pollution water such as tail water from urban sewage plants and farmland irrigation backwater. Background technique [0002] Low-pollution water, including tailwater from urban sewage plants, backwater from farmland irrigation, etc. Because its water quality is between the sewage treatment plant discharge standard and the surface water V standard, once it is discharged into the receiving water body, it will greatly increase the organic matter and nutrient load in the water body, so it is currently regarded as the main external cause of eutrophication in the water body one of the sources. [0003] At present, for the treatment of low-pollution water, countries all over the world adopt ecological engineering methods, ...

AI Technical Summary

Problems solved by technology

However, filling the hollow bricks reduces the matrix content in the wetland and reduces the effective purification volume inside the wetland; in addition, the intermittent operation of the device is not possible in some cases (such as in-situ purification of river water)

These disadvantages limit the use and promotion of the technology

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