Underground integrated equipment SBR process

Underground integrated equipment SBR process

Application of SBR process and its improved version

The SBR process forms an A2/0 system in a time series through an automatic control program, which has the characteristics of economic efficiency and flexible control. It has good effects in nitrogen and phosphorus removal and is suitable for small and medium-sized wastewater treatment plants.

The typical SBR process has certain technical problems. Firstly, the intermittent water inlet and intermittent aeration methods, as well as the frequent start and stop of the blower aerator due to intermittent operation, greatly affect the stability of the entire process. The utilization rate of the reaction tank in the aeration stage is also relatively low; Secondly, due to intermittent water inflow, the design of the self-control system and the installation of sequential inlet gate valves become more complex. When the water inflow is large, multiple sets of reaction tanks need to be operated in parallel, increasing the overall complexity of the system; Thirdly, for some difficult to degrade organic wastewater with high concentrations, the reaction time is relatively long. In order to solve the above problems, numerous researchers have made improved variants of typical SBR processes, including mature processes such as ICEAS, DAT-IAT, CASS, etc.

The characteristic of CASS process is the addition of a pre reaction zone at the inlet of the reactor, which operates continuously with intermittent drainage. The pre reaction zone can regulate the water flow, while the main reaction zone is responsible for aeration and sedimentation. The ICEAS process can also be regarded as an SBR process with continuous water inflow and intermittent drainage. The third sewage treatment plant in Kunming has adopted this process and has achieved good operating results.

The DAT-IAT process sets up DAT and IAT tanks in the same reaction tank, separated by guide walls. The DAT tank continuously receives water and aerates, maintaining the hydraulic balance of the system and effectively improving the stability of system operation. Continuous aeration also reduces the degradation of difficult to degrade organic matter, shortens the treatment time for high concentration organic wastewater, and correspondingly shortens the operation time of the blower aerator; In addition, the continuous inflow of DAT pool can be achieved using ordinary sewage pumps, greatly reducing the complexity of the system. This process has achieved good application results in the Tianjin Economic and Technological Development Zone Sewage Treatment Plant and the Fushun Sanbaotun Sewage Treatment Plant.

The CASS process, as an improved version of the SBR process, adds a biological selection zone, also known as a pre reaction zone, at the inlet of the SBR tank, achieving continuous water inflow and intermittent drainage. The aeration, sedimentation, and drainage processes of the entire process are cyclically operated in the same tank, eliminating the need for the secondary sedimentation tank and sludge reflux system of conventional activated sludge processes. The Beijing Aerospace City sewage treatment plant adopts this process.

Underground integrated equipment SBR process