SBR

 

Sequencing Batch Reactor (SBR)

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is an advanced technology that uses a fill and draws activated sludge system for wastewater treatment. It is best for treating both industrial and municipal wastes. The main difference between SBR technology and other STP technologies is that SBR uses a single batch reactor/single tank to process the equalization, aeration, and clarification compared to other technologies that use different batch reactors for various processes.

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SBR technology is considered to be one of the highest performed solutions for wastewater treatment. It requires minimum maintenance and has low costs. It can handle continuous batch operations successfully. The distinct qualities of SBR technology are as follows: 

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• 1. High removal capacity 

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• 2. Versatile 

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• 3. Compliant with stringent discharge standards

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• 4. High-quality product generation

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Here, we know briefly about the SBR technology used in sewage treatment plants (STP) to remove the contaminants from the wastewater. Let us learn about the functioning of SBR technology in STP. 

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What does SBR technology do in STP

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One of the most advanced and high-class technology for treating wastewater, it works in various phases in a single batch reactor, often known as tanks. When sewage water is sent to the SBR tanks, then the activated sludge system gets activated. After that, activities occur in a timely sequenced manner, and the water gets purified.

 

The convenient sequenced actions are explained here as below: 

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• 1. Filling: This is the first step in water purification. In this step, the influent wastewater is filled in the tank. The water gets filled in the SBR tank. The water must get adequately filled so that the food to microorganisms ratio remains appropriate.  

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• 2. Aeration: This is the next step in which the reaction occurs. Microorganisms utilize the ammonia, nitrogen and Biochemical Oxygen demand (BOD). The rate at which the treatment works is directly proportional to the sludge mass and time is taken for aeration. Not only this, but it also depends upon the level of impurities and the degree of nitrification.   

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• 3. Settling: This is the next step which takes around 60 to 90 minutes. It also depends upon the number of cycles per day. As the name suggests, in this step, the aeration stops, and the sludge gets settled. 

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• 4. Decanting: This is the next step which is itself a process. Decanting is when the effluent is removed from the tank without disturbing the sludge settled at the bottom. 

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• 5. Idling: Idling is described as the waiting time between the two filling cycles. 

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• 6. Sludge wasting: After all the steps, the sludge gets accumulated in the tank. When it crosses the threshold limit, it needs to be discharged from the system. Two parameters are considered to be better to keep control over the quality of sludge wasting. The two parameters are as follows: 

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• i)  Mixed Liquor Suspended Solids (MLSS)

• ii) Mean Cell Residence Time (MCRT) 

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So, this was the functioning of SBR technology in Sewage treatment plants.

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