How to Use Slurry Pumps

The slurry pump is a heavier and stronger version of a centrifugal pump used to handle harsh or abrasive applications. Standard centrifugal pumps are used mainly to dissipate clear liquids, while slurry pumps are used for hydraulic solids transportation.

The term “Slurry Pump” refers to all of the devices used in the transport of solids. More specific names are given to them based on the size of the solid being transported or based upon its particular use.

The slurry pump is used to transport mud, clay, silt and sand in the size range of solids up to 2 millimeters. Sand and gravel pumps handle the transporting of shingle and gravel in the 2 to 8 millimeter range. Additionally, gravel pumps may transport solids up to 50 millimeters in size. Dredge pumps are used to handle solids up to and exceeding 50 millimeters.

Specific names are also based on the application or use. Froth pumps handle frothy slurries, mainly in flotation. Carbon transfer pumps provide the gentle hydraulic transportation of carbon in pulp and carbon in leach circuits. Sump pumps are mainly operating pumps from floor sumps that have submerged houses but dry bearings and drives. Submersible pumps, like the name implies, are fully submersed, including the housing and drive.

Depending upon the application, the slurry pump can be installed dry, semi-dry, or wet. Most horizontal slurry pumps are installed dry. In this case, the bearings and the drive are kept out of the slurry, and the wet end is closed. The slurry is free standing and clear of any of the liquids. The vertical tank may also be installed dry. This has an open sump with the pump casing mounted directly under the tank. The slurry is fed from the tank and expelled horizontally. No submerged bearings are required in this design.

Semi-dry installation is a special configuration for dredging operations. Horizontal pumps are used with wet ends and submerged pads. For this application, special sealing considerations must be made for flooded bearings. Wet installations are used when there is a need for a pump that is completely submerged. An example is removing slurry from a tub where there is a very volatile level of free slurry. In wet installations, both housing and drive are flooded, which require special design and sealing considerations.

When determining slurry pump design, the type of application is considered to ensure proper performance under a variety of conditions. They are designed to handle highly abrasive, abrasive, and mildly abrasive conditions.