1, Suihua oxidation pond. The pond covers an area of10.3 million square meters, with a volume of 380,000 cubic meters, 2 pumping stations, 4 simple pumping stations, brick seepage control channels10.95 million meters and an irrigation area of 6,000 mu. According to the water quality analysis of sewage main pumping station and oxidation pond, the purification effect is obvious, which can meet the water quality standard of farmland irrigation. Irrigation of farmland with this purified sewage for seventeen years has no pollution to soil, vegetables and groundwater. The purified sewage contains 22.5 mg/L of nitrogen, 2.93 mg/L of phosphorus and 6.0 mg/L of potassium, saving 3 1.430 kg of chemical fertilizer and 654,380+0 million tons of groundwater every year. From the plot experiment and large-scale investigation, all kinds of vegetables have increased production, with an average annual increase of 50-80 thousand Jin, 7- 10 days early, and an average annual increase of 250-300 thousand yuan. Therefore, using oxidation pond to treat sewage in small and medium-sized cities is an important water and fertilizer resource for agricultural production, which can also improve soil fertility and increase vegetable yield.
2. Yima Coal Industry Group Co., Ltd. has a coal mine oxidation pond. In order to clean up the pollution of mine water to Jianhe River, in recent years, the mine has invested more than 400,000 yuan to transform an abandoned mine pit into an oxidation pond with a volume of10.5 million cubic meters, and the monthly treatment of mine water is 82,000 cubic meters. This new way to control mine water pollution not only relieves the serious water shortage in mining areas, but also produces good economic and social benefits. The mine water treated by the oxidation pond can be used as industrial water in the well and underground, and the oxidation pond can also raise fish, with an annual output of more than 20 thousand kilograms of fresh fish. Now the oxidation pond is surrounded by trees and has become a famous scenic spot.
3. Oxidation pond of Gaotang Paper Group. In order to solve the problem of sewage discharge, the group invested120,000 yuan to build an oxidation pond, covering an area of more than 600 mu and running around the clock. This makes the paper-making wastewater treated by the company can be used for aquaculture and agricultural irrigation, and 80% of the water can be recycled for production, realizing the harmless comprehensive utilization of paper-making wastewater and becoming a zero-pollution emission enterprise.
Ecological engineering of sewage treatment and utilization in Dongying City, Shandong Province
1, project introduction
The ecological project of sewage treatment and utilization in Dongying City was completed in June 2000, with a designed water treatment capacity of 65,438+10,000 t/d, covering an area of about 1 10 hectare, with a total investment of 67 million yuan. It is a well-designed sewage treatment plant with stable pond treatment system at home and abroad. The quality of sewage is as follows:
▲ Table 4 List of influent quality projects BOD COD SS TN TP NH3-N concentration (mg/L) 70 150 70 30 5 20 This project adapts to local conditions, and after proper trimming and separation, an existing reservoir is transformed into a high-efficiency anaerobic tank, aerated pond, aerated fish pond and other treatment units; The nearby saline-alkali wasteland will be built into ecological utilization units such as fish ponds, lotus ponds and reed ponds.
2, the main processing unit design
(1) fine grid: single grid width 1.4m, grid gap 8mm, grid width 10mm, effective water depth before grid 0.8m, grid velocity 0.9m/s and grid installation angle 75.
(2) grit chamber: the plane design size of each group is 12.0m×3m, the effective water depth is 1.2m, the inclination angle of sand hopper is 55, and the height of sand hopper is1.85m.
(3) High-efficiency compound anaerobic pond: the average length and width of each anaerobic pond are about 138.88m, 65.87m, the effective water depth is 5.0m, and the residence time of sewage in the anaerobic pond is1.68d..
(4) aerated pond: The average length of aerated pond in each group is 133.37m, the width is about 66.3 1m, the effective depth is 3.6m, and the residence time of sewage in aerated pond is1.29d.
(5) Inflatable fish pond: The total area of the pond is 23.24 hectares, the effective depth of the pond is 3.5m, and the hydraulic retention time of sewage in the pond is 8. 13d.
(6) Fish ponds: the total area of fish ponds is 12.09 hectares, the effective water depth is 2.5m, and the residence time of sewage in them is 3.02 days.
(7) Lotus pond: the total area is 7.56 hectares, the effective water depth is 1.2m, and the hydraulic retention time of sewage in it is 0.91d..
(8) Weitang: The areas of Weitang I and Weitang II are 18.09 hectares and 19.09 hectares respectively, with an average effective water depth of 0.5m and a total hydraulic retention time of1.85d..
3, the operation effect
The trial operation of this project began on June 5, 2000+10. Under the condition that fry, lotus root and reed are not put in the fish pond, the final effluent completely meets the requirements of the Second Class Standard for Integrated Wastewater Discharge (GB 8978- 1996).
4, the characteristics of the project
(1) The stabilization pond treatment system is adopted in this project, which organically combines the treatment and utilization of sewage, and realizes the recycling of sewage, which is of great significance for alleviating the contradiction of water shortage in Dongying City.
(2) In the design of this project, special attention should be paid to the coordination between the treatment system and the surrounding environment and the beautification of the environment. The dam was built neatly, all protected by rubble; As an artificial attraction, the inflatable fish pond has built the sewage treatment plant into an ecological park.
(3) Compared with the traditional activated sludge process, this project has the advantages of low capital investment, low operation cost and convenient maintenance and management.