High-load artificial wetland system with enhanced nitrogen and phosphorus removal function

Abstract

The invention discloses a high-load artificial wetland system with an enhanced nitrogen and phosphorus removal function. The system comprises a wetland I and a wetland II which are communicated at thebottom, wherein the wetland I comprises water sprinkling devices, a first packing layer, a second packing layer and a first broken rubble layer which are laid from top to bottom; the wetland II comprises a second broken rubble layer, a third packing layer and a fourth packing layer which are laid from bottom to top; the artificial wetland system further comprises a water collecting and distributing pipe and a drain pipe, the water collecting and distributing pipe is arranged in the first broken rubble layer and the second broken rubble layer and used for communicating the bottoms of the wetlands on the left side and the right side; the water collecting and distributing pipe is connected with the drain pipe; a water collecting and draining pipe is arranged at the bottom of the fourth packing layer of the wetland II and provided with an electrically operated valve which is used for controlling draining time of the system. The system is simple in structure, high in integration level, high in hydraulic loading, good in nitrogen and phosphorus removal effect and lower in investment and operating cost, consumes no energy during oxygen supply and is not prone to blocking.

Description

technical field [0001] The invention belongs to the technical field of sewage treatment in environmental engineering, and in particular relates to a high-load constructed wetland system for strengthening denitrification and dephosphorization. Background technique [0002] In order to protect the ecological environment and reduce water eutrophication, my country's sewage discharge standards are becoming increasingly strict, which requires deep nitrogen and phosphorus removal of the effluent from the secondary aerobic unit (the tail water of the sewage treatment plant). Microbial aerobic nitrification and anoxic denitrification are considered to be the most important ways of wastewater denitrification. However, in the aerobic removal of NH 3 -N at the same time, the organic carbon in the sewage is basically removed, so that the post-denitrification unit is severely inhibited due to the lack of organic carbon sources. [0003] Therefore, it is necessary to add an organic carb...

AI Technical Summary

Problems solved by technology

These supplementary methods of organic carbon sources have effectively improved the effect of denitrification and denitrification, but there are still some problems: the hydrolysis of solid carbon sources takes time, the release of carbon sources is unstable, the organic carbon sources in the filler will be exhausted soon, and the duration of efficient denitrification Short; adding hydrolyzate requires artificial regular addition of plants for hydrolysis, which is labor-intensive for large-scale projects, and plant hydrolysis residues need to be disposed of; it is most economical and convenient to use raw sewage organic carbon sources, but raw sewage will also be brought into NH 3 -N, in the denitrification section is anoxic environment, the NH 3 -N removal ability is weak, easy to lead to water NH 3 -N exceeds the standard

It can be seen that efficient, continuous, and low-cost denitrification is a difficult problem faced by sewage treatment technology, which makes it difficult to discharge TN in the effluent.

[0004] In addition, the effluent of the secondary aerobic unit usually contains a relatively high concentration of total phosphorus. Adding a flocculant to remove phosphorus can achieve a good phosphorus removal effect, but the cost is high, and it is more difficult to implement in the practice of decentralized domestic sewage in villages and towns.

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