污水处理工程--两段式活性污泥工艺

我国中小城市的污水处理通常有如下特点(1 )工业废水所占比重较大,甚至超过50 %,致使要处理的城市污水的污染物浓度较高,污染物负荷变化较大 ;(2)城市财政状况比较紧张,可用于建设污水处理厂的资金有限.两段式活性污泥工艺是对传统活性污泥工艺的改进,在好氧处理之前采用一个缺氧或厌氧段,用于有机物的水解酸化或生物除磷.两段式工艺有以下优点处理效率高、工程投资和日常运行费用低,更适合我国国情.本文以两个工程项目为例,论述了两段式活性污泥工艺的工程设计与实际应用.山东省招远市污水处理厂于1999年7月投入运行,处理后排放水中的污染物指标低于设计值.蓬莱市污水处理厂工程即将竣工,设计处理能力20000m3 /d,工程总投资约1200万元,远远低于目前国内的平均水平.

Wastewater treatment plant---two stage activated sludge process

The wastewater treatment in medium or small sized cities in our country usually possess the following characteristics: (1) industrial wastewater constitutes a large portion of total wastewater to be treated (even more than 50%), resulting in higher and variable pollutants' concentration; (2) the funds for building wastewater treatment plants are limited. Two stage activated sludge process is an improvement of conventional process, which adopts anoxic stage before aerobic stage for hydrolysis and acidulation of organic substances or phosphorus removal. The process is suited to local conditions by using modified structures and has some advantages: higher treatment efficiency, lower construction investment and lower energy consumption in operation. This paper takes two existing projects as examples to show the engineering design and operation results of two state activated sludge process. The wastewater treatment plant in Zhaoyuan City has been operated since July, 1999. After treatment, the pollutants in discharge water are lower than design value. The wastewater treatment plant in Penglai City has a capacity of 20 000m 3 /d, and total investment of 12 million yuan in RMB which is much lower than domestic average level.