Basic Wastewater Operator Practice Exam

What kind of reactor is used in a sequencing batch reactor (SBR)?

1. Continuous flow reactor

2. Batch reactor

3. Plug flow reactor

4. Parallel reactor

The correct answer is: Batch reactor

A sequencing batch reactor (SBR) is classified as a batch reactor because it operates in a process where the influent wastewater is added to the reactor all at once (in batches). In this system, the treatment process occurs in a sequence of phases, including fill, react (aeration or biological treatment), settle, and decant. Each batch of wastewater undergoes the complete treatment cycle, which allows for the efficient treatment of a defined volume of wastewater. This operation allows SBRs to effectively manage variations in flow and load, making them suitable for various treatment scenarios. Unlike continuous flow reactors, which maintain a constant input and output of materials, batch reactors process a single batch at a time before beginning the next cycle. This method makes SBRs versatile for meeting different regulatory requirements and operational challenges.