Tennessee Wastewater Operator Practice Exam

Which of the following describes a single rake screen?

1. May be located in a bypass channel

2. Interlocking links, no lower sprocket

3. Single operating cycle

4. Integrate wash press

The correct answer is: Single operating cycle

A single rake screen is specifically designed to perform its function during a single operating cycle, which means it processes the incoming flow through one complete movement of its rakes. This type of equipment is essential in wastewater treatment as it helps to remove large solids from the water before it moves forward in the treatment process. During its operation, a single rake screen captures the debris when the rakes rise and then conveys that material out of the flow path, allowing for a straightforward and efficient operation. The design focuses on a singular action, which minimizes mechanical complexity and makes maintenance easier. In contrast, the other characteristics of a single rake screen do not accurately define its operation. For example, while it might be used in various configurations, specifying it must be in a bypass channel or requiring interlocking links with no lower sprocket does not apply universally to all single rake screens. Moreover, integrating a wash press pertains to the mechanism of cleaning and dewatering the collected debris, which is not an inherent characteristic of a single rake screen itself but rather an additional feature of some models.