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Aeration is a very important step to remove BOD and partial COD to meet the discharge requirement, BOD is reduced by bacteria in the aerated basin and the biomass is carried over with the effluent into a secondary clarifier where solids are allowed to settle, then concentrate an removed. Part of the settled sludge is drawn off as waste, and the rest is recycled to maintain a high level of micro-organisms in the biological system. Process is a complete-mixed activated sludge process.
生化处理是去除废水中BOD及部分COD以满足环保要求的重要步骤。BOD通过曝气池内生物菌体的作用而去除,生物菌体随着废水在二沉池沉淀、浓缩、去除。部分生物菌体返回曝气池以维持曝气池内生物菌体的浓度,另一部分生物菌体作为污泥排放掉。
The benefits of submerged jet aeration is
· Low-maintenance – there is no moving parts in aeration tank. Jet aerator is made from FRP and life time is at least 10 years.
· A more compact layout and lower real estimate requirement result from the deeper aeration tank. Waste water depth is usually 6.5-9.5m.
· Oxygen supply and waste water re-circulatioin is in-dependedly. When oxygen demand is low, one of the air blower can be turn off and the air flow can be adjusted to match the process requirement .
· The higher oxygen transfer capacity of submerged jets provide higher power density, and it translate into lower power consumption and high degree of BOD removal.
· Less foam and odor compared surface aerators
深水射流曝气系统有以下优点:
· 维修费用低--曝气池内没有移动件,曝气头由玻璃钢制成,曝气头寿命至少15年。
· 占地面积小、土建费用低--深水射流曝气系统的废水深度一般为6.5-9.5米,所以废水处理系统布置紧凑,占地面积小、土建费用低。
· 风量根据BOD值进行调节而节约能源--射流曝气系统的供氧及废水循环为独立的系统,风量可以根据BOD值通过调节一台风机的风量、关闭一台风机或开启备用风机进行调节,以节约能源。
· 深水射流曝气是功率效率最高的曝气设备之一,所以在同等动力消耗状态下,深水射流曝气的BOD去除率较高。
Aeration system comprises one circle concrete tank which equipped with one (1) set of submerged aeration header, one (1) set of re-circulation pumps and air blowers. Blowers and pumps will be by contractor based on KLA’s specification.
深水射流曝气系统为一圆形曝气池,有一组射流曝气头,一个循环水泵。风机及水泵由总包商基于KLA公司的概念设计。
The basin for complete mix operation is that the volume of mixed liquor flowing through the tank is several times of the influent flow. While an amount of flow equal to the influent is continually displaced to the secondary clarifier, tremendous dilution is provided as the influent is intimately mixed with the liquor re-circulated.
射流曝气系统的运行模式为完全混合式,曝气池内废水的数量为进入曝气池废水的许多倍,这样进入的废水被马上稀释,与此同时与进入曝气池废水同样数量的废水流到二沉池。
Jet aeration loading factors:
Number of basin 1
Basin size dia. 40 m x SWD 6.5 m
Type of basin Circle
HRT about 19.5 hours
SOR (kgO2/h) 511
MLSS( mg/l) 5000
Plant elevation 10 m
Residual DO 2 mg/l
Number of jet aerators 1
Jet aerator material FRP
Capacity of blowers 95 m3/min
Out let air pressure at interface 6.7 m
Number of re-circulation pumps 1
Pump capacity 52 m3/min
Liquid pressure at interface 6.8 m
Aerator life time at least 15 year.
射流曝气池设计负荷参数:
曝气池数量 1
曝气池尺寸 直径40 m x废水深 6.5 m
曝气池形状 圆形
水力停留时间 ~ 19.5 小时
理论供氧量(kg/h) 511
MLSS (mg/l) 5000
工厂海拔高度 ~ 10 m
曝气池溶解氧量(mg/l) 2
曝气池曝气头数 1
曝气头材质 玻璃钢
供气量 95 立方米/分
在曝气头法兰连接处的空气压头 6.6 m
曝气池内循环泵数 1
循环泵循环量 52立方米/分/台
在曝气头法兰连接处的水力压头 6.8 m
曝气头寿命 大于 15年
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