In this project, 13 side circulating contact oxidation projects, oxidation pond projects and constructed wetland projects are designed to reduce the pollutants continuously entering the river and improve the water environment.
(1) The side circulation contact oxidation project mainly uses the current pond in the beach land to connect the Yitong River and the pond, and arranges floating wetland, artificial water grass, submerged plants, aeration and oxygenation (the aeration device is relatively fixed with the floating wetland) and other measures in the pond. The river water is in full contact with the measures in the pond to remove the organic matter, nitrogen, phosphorus and other pollutants in the water body, so as to make the effluent for a long time Keep in the surface water to purify the water body and achieve the purpose of ecological restoration.
(2) Oxidation pond, also known as stabilization pond or biological pond, is a kind of sewage biological treatment technology, which has been artificially and properly trimmed land and set up a dike and anti-seepage layer. It mainly relies on the natural biological purification function to purify the sewage. The wastewater flows slowly in the pond and is stored for a long time. The organic pollution is degraded and the wastewater is purified through the metabolic activity of microorganisms living in the wastewater and the comprehensive action of various organisms, including aquatic plants.
(3) The constructed wetland system includes pond system unit, subsurface flow wetland unit and surface flow wetland unit. The river water of Yitong River is lifted to the pond by pump for buffering and settling to remove particles, and then enters the subsurface flow wetland unit. The water body is purified by the function of substrate filler in the subsurface flow wetland and the absorption of reed and other plants. The sewage after the subsurface flow wetland treatment enters the surface flow constructed wetland In the wetland, the pollutants are removed through the absorption of wetland plant roots, and at the same time, the water surface landscape of the wetland can be built.