Background

Ningbo Xinzhou STP was built and put into trial operation in 2011 with A2/O process, 160,000 m3/d design treatment scale and the original design effluent implements I-B standard. Since 2016, the daily treatment capacity of the STP has approached 160,000 m3/d, running at full load. The core objective of the retrofittion is to use MBBR process to transform its bioreactor, so as to make COD, BOD, NH3-N, TN and other effluent indicators have reached the Class IV water quality standard steadily.

Implementation Idea     

The current A2/O bioreactor was retrofitted by MBBR process. The load of pollutant treatment was increased byadding suspended carrier in the aerobic zone, and denitrification effect were enhanced. In addition, 160,000 m3/d of reserved land for reclaimed water in the west side of the STP was converted to further treatment measures to strengthen SS and TP removal.

Project highlight

1) Mature technology with stable performance;

2) Little impact on production and operation;

3) Maintaining the general planar functional zoning of the plant area, reserving land for use, has little impact on the overall planar layout;  

4) Increasing fillers quantity can meet the long-term upgrading;

5) Fewer project investment;

6) Low operating costs, no need for external carbon sources, energy saving and significant; consumption reduction;

7) Meeting the Class IV water quality standard.