Tennessee Wastewater Operator Practice Exam

Which valve type is commonly used for air isolation and control in turbo blower systems?

1. Check valve

2. Gate valve

3. Butterfly valve

4. Ball valve

The correct answer is: Butterfly valve

The butterfly valve is commonly used for air isolation and control in turbo blower systems due to its design characteristics, which allow for efficient flow regulation and minimal pressure drop. Butterfly valves consist of a rotating disc that can be turned to various degrees, enabling precise control of fluid flow. This makes them particularly suitable for applications where controlling air in blowers is critical, as they can quickly adjust to varying flow rates while maintaining energy efficiency. Furthermore, butterfly valves are known for their compact size and relatively lightweight compared to other valve types, which is advantageous in space-constrained environments like wastewater treatment facilities. Their ability to perform well in both fully open and fully closed positions also ensures reliable operation in managing air supply. In contrast, check valves mainly prevent backflow and are not designed for flow control. Gate valves are typically used to start or stop fluid flow and don’t provide the fine control that a butterfly valve offers. Ball valves, while excellent for on/off control, can be less effective in throttling applications because they are not designed for regulating flow as precisely as butterfly valves. This distinction makes the butterfly valve the preferred choice in these specific applications.