High porosity filler enhanced denitrification method and device for constructed wetland
By constructing high-porosity fillers and gradient resistance layers, combined with temperature-adaptive microbial communities and biomimetic water flow distribution, the problems of difficult oxygen transfer and unstable nitrogen removal efficiency in traditional constructed wetlands have been solved, achieving stable and efficient nitrogen removal.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CHINA RAILWAY SEVENTH BUREAU GRP XIAN RAILWAY ENG CO LTD
- Filing Date
- 2025-07-17
- Publication Date
- 2026-06-09
AI Technical Summary
In traditional constructed wetland systems, the low porosity and low permeability of conventional fillers such as gravel and crushed stone make it difficult for oxygen to be transferred to the deeper layers of the wetland, which limits the activity of nitrifying bacteria and affects nitrogen conversion efficiency. Moreover, existing improvement measures are energy-intensive, complex to manage, and have unstable effects, especially when the denitrification efficiency is unstable under temperature changes.
By screening and proportioning lightweight fillers with high porosity, a gradient resistance layer is constructed to induce oxygen concentration fluctuations, temperature-adaptive microbial communities are cultivated, a biomimetic water flow distribution is designed, and the oxygen transfer is enhanced by utilizing the tidal respiration effect, forming a complementary symbiotic network to achieve a stable denitrification effect.
Under different seasonal conditions, the system can maintain stable nitrogen removal activity and improve nitrogen removal efficiency through naturally driven deep oxygen supply, overcoming the limitations of traditional wetlands that are greatly affected by temperature, and achieving highly efficient nitrogen removal.
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Figure CN120717611B_ABST