Stormwater Treatment And Use Of Technology In Xi'an City

With the advance of the urbanization process in China, the rapid development of economy and population, water supply and demand have become increasingly prominent, in addition to stormwater runoff pollution affecting the urban water environment, and resource utilization of urban stormwater runoff pollution can not only control, but also alleviate the urban water pressure. This article relies on rainwater utilization Shaangu power demonstration project on the study area were improved rainwater collection systems, regional analysis of the characteristics of rain water for rainwater runoff pollution and resource utilization issues, proposed the use of artificial rain water filtration system to be distributed processing, analysis of the filtration system and the removal of pollutants hydraulic loading system to respond to shocks. Main results are as follows:(1) Rainwater collection tank and through the new part of rainwater tanks in series, so that the effective collection area of the plant water 90000m², in the use of rainwater capacity 36169m³. Meet the water needs of the whole green plant had an annual water savings of about 12 million.(2) Stormwater runoff study area in the normal range of pH values, the other indicators are more than "Surface Water Environment Quality Standard" (GB 3838-2002) of the requirements of Gradeâ…¤. Rain the water quality changed greatly throughout the year, water quality is relatively good in rainy season, relatively poor water quality in the dry season. Rainwater COD is 76.85 278.53mg / L, SS is 96 417 mg / L, NH₃-N was 2.68 5.64 mg / L, and TP was 0.28 1.35 mg / L.(3) Rain water for the area and terrain characteristics, designed two different flow patterns in the infiltration pond, pool filtration II vertical flow filtration tank, and its main parameters are: the design flow: 2.6m³ / h; hydraulic load: 1.0 m / d dimension: L×B×H = 5×4×1.3; filter thickness: 1.0m; Media: hierarchical arrangement of natural river sand, followed by flat bottom paving, gravel, coarse sand, fine sand. VI mainly horizontal flow filtration pool complex flow filtration tank, the main parameters: the design flow: 4.0m³ / h; hydraulic load: 1.3m / d; Size: L×B×H = 6×4×1.3 ; filter thickness: 1.0m; Media: natural river sand layer layout. Alternate wetting and drying are used to run way, wet dry ratio: 1:2 (8h: 16h).(4) Two different flow patterns in the stable operation of the percolation pond there is a certain time before the adaptation period, stable treatment effect after the rain are good, II filter effluent COD, SS, NH₃-N, TP average concentration of 13.26 mg / L, 7.75 mg / L, 4.02 mg / L, 0.36 mg / L, corresponding to an average removal rate was 87.33%, 90.81%, 59.58%, 64.27%; VI filter effluent COD, SS, NH₃-N, The average TP concentration of 16.69mg / L, 8.75mg / L, 4.29mg / L, 0.37 mg / L, corresponding to an average removal rate was 83.47%, 89.53%, 56.13%, 61.97%. To achieve reuse of rainwater and stormwater runoff pollution controls the adverse impact on the environment.(5) Comparison of two pool filtration, filtration pool II (vertical flow) than the percolation pond VI (horizontal flow-based composite flow) of the treatment effect to be slightly better, probably, and packing, flow pattern, into the water quality, hydraulic loading and other factors related to. Two hydraulic load filter can withstand greater impact, COD, SS, NH₃-N in the hydraulic loading of 1.5m / d or less is better removed, TP at 2.0m / d the following removal better. Actual operation can return to the needs of water, adjust the hydraulic loading, operation more flexible.