Water quality standard and treatment technology of Yinchuan No.1 sewage treatment plant

The measured water quality data of Beihuan Pumping Station and Ximen Pumping Station in the service area 1995 show that the content of various pollutants in sewage is low. Combined with the inlet water quality and design water quality of some domestic sewage treatment plants during operation, according to the information and requirements of local environmental protection departments, the design inlet and outlet water quality is determined as follows:

Table 2- 1 influent and effluent CODcr ≤ 350mg/l ≤120mg/l BOD5 ≤ 160mg/l ≤ 30mg/l ss ≤ 200mg/l pH = 6 ~ 9, and the designed minimum sewage temperature is1l.

Land for sewage treatment and development is reserved in the plant area, and sewage reuse treatment facilities can be added according to the reuse requirements.

In the selection of sewage treatment process scheme, DE oxidation ditch process and SBR process are preliminarily selected for comparison. After multi-party investigation, technical and economic comparison and multi-party demonstration, the SBR process of America and Korea was finally determined. Due to the long age of the designed sludge, the sludge has been basically stable in the biological pool, and the sludge is directly dehydrated without digestion. See figure 2- 1 for the process flow of the sewage plant.

Figure 2- 1 sewage sludge treatment process flow chart