A peristaltic pump is a type of ______ pump.

A peristaltic pump is classified as a positive displacement pump because it moves fluid by mechanically drawing it into a fixed volume and then forcing it out through the discharge. This process occurs through the action of rollers compressing a flexible tube, creating a series of moving pockets that carry the fluid along. The defining characteristic of positive displacement pumps is their ability to deliver a consistent volume of fluid with each cycle, regardless of changes in pressure, which is essential in applications requiring precise flow rates, such as in wastewater treatment.

Centrifugal pumps, on the other hand, rely on rotational energy to impart velocity to the fluid, which is then converted to flow; they do not create a fixed volume of fluid movement in each cycle. Diaphragm pumps are another type of positive displacement pump, but they operate using a flexible diaphragm rather than rollers, emphasizing different mechanics. Volumetric is a broader category that can include various types of pumps, but does not exclusively denote how a peristaltic pump operates. Therefore, identifying a peristaltic pump as a positive displacement pump is accurate and reflects its operational principle effectively.