Bioretention system suitable for processing urban initial rainwater in severe nitrogen pollution area

Abstract

The invention discloses a bioretention system suitable for processing urban initial rainwater in a severe nitrogen pollution area. The system is composed of a water inlet facility, an overflow facility, plants, a filler layer, an internal water level regulating and controlling facility and a water discharging facility; the water inlet facility intercepts runoff with extremely poor water quality inthe initial stage of rainfall through a surface-layer water inlet pipe; the overflow facility includes an overflow weir and an overflow pipe; the plants are planted at the surface of the filler layer, and a planting mode of the plants is optimized according to the nitrogen removing characteristics of the plants; the filler layer realizes high-efficiency nitrogen removal through addition of a novel nitrogen-removing material; the water discharging facility promotes infiltration, interception and discharge of rainfall runoff in the system by utilizing perforated water-discharging pipes arrangedat the bottom of the system; and the internal water level regulating and controlling facility is a U-shaped pipe, an internal water storage layer is formed in the water inlet process through a theoryof communicating vessels of the U-shaped pipe, a height of the U-shaped pipe can be adjusted to create the aerobic-anaerobic alternating environment required for the nitrogen removal, and the top ofthe U-shaped pipe is provided with a sensor to control water inflow to ensure effective storage and retention of the initial rainwater.

Description

technical field [0001] The invention relates to a biological retention system suitable for treating early rain in cities in areas with severe nitrogen pollution, and belongs to the field of water treatment. Background technique [0002] The construction of sponge city has become the top priority of the national water control strategy. However, under the background of the "sponge city" construction vigorously promoted by the state, the design and optimization of sponge city measures still need to be strengthened. Bioretention system has become one of the main measures for low-impact development, promotion and application at home and abroad because of its efficient runoff retention capacity, peak reduction capacity and pollution load reduction capacity. [0003] However, the existing technical measures focus on the control of waterlogging and the regulation of water volume, ignoring its purification function on the quality of rainwater, especially the initial rainwater. Stud...

AI Technical Summary

Problems solved by technology

However, the existing technology fails to strengthen the purification and regulation of the initial rainwater according to the characteristics of the initial rainwater.

Published patent (CN203700035U): A bioretention pond that enhances the nitrogen removal effect in storm runoff. The nitrogen removal measures determined in this patent mainly include reverse filtration backflow accessories to create an internal anoxic zone, but the construction of an external water storage tank is of great importance to Land shortage areas are more difficult, and the effect of comprehensive plants and fillers is not considered, and the effect of efficient nitrogen removal is limited. At the same time, the initial effect of urban rainwater is not considered, which may lead to problems such as unsatisfactory initial rainwater purification effect

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