What Is a Slurry Pump?

A slurry pump is a type of water pump intended for use in situations where solids are accidentally or intentionally suspended in water. As centrifugal pumps, slurry pumps rotate water by way of impeller. Depending on the specific application, rotation controls particulates and prevents solids from entering and causing damage or corrosion to other machinery parts. In other applications, a slurry pump is used to keep solids suspended by preventing any settling or other separation of the solids from a liquid medium. Certain compounds and other materials require suspension in water for safe transport, utilizing a slurry pump to keep compounds suspended through constant motion.

While several slurry pump designs appear in the marketplace, the basic operating principles remain the same. The pump is housed in a high pressure casing, typically in a semi-spiral shape. Inside the casing are various drive devices that turn a shaft and bearing assembly. Impellers are located along the shaft, with vanes to help create the centrifugal force needed to spin the slurry. Once the drive devices are engaged, bearings keep the shaft turning smoothly and consistently, while the impeller swirls or centrifuges the slurry.

To illustrate the effects of a slurry pump, consider a mixture of sand and water in an ordinary drinking glass. Swirl the glass at a high enough rate of speed and the sand will remain suspended in the water. Centrifugal slurry pumps operate on the same principle, although driven by belts, drives, and other mechanical components to create the high pressure centrifuge needed for large volumes of heavy slurry.

Using a slurry pump is common in certain industrial applications. For example, the mixture of water and cement forms a type of slurry that must remain in motion to prevent water evaporation and subsequent drying of the cement into concrete. Cement mixer trucks are a common example of a centrifugal slurry pump used to transport a slurry compound. Paper production is another application involving a slurry pump. Wood pulp and water are mixed and centrifuged via a pump during the production of various papers.

Different applications naturally require different centrifugal pumps. Typically, a slurry pump is intended for use as a submersible pump, since applications most often require high pressure that is best achieved when the impeller is placed in the slurry. Slurry weight determines the type, design, and capacity of slurry pump needed. Such designs are easiest divided according to light, medium, or heavy slurry weight.

Light slurry needs normally result from the accidental or unwanted introduction of particulates, such as with hard water or other solutions with less than five percent solids. The presence of large particulates, heavy concentrations of particulates, or compounds needing suspension for transport require medium or heavy slurry pumps. Particulate size and concentration percentage determine if a medium or heavy slurry pumps is required.