Slurry Pumps

What is a slurry pump?

Slurry pumps are designed for move abrasive, thick, or solid-filled slurries through a piping system. Due to the nature of the materials they handle, they tend to be very heavy-duty pieces of equipment, made with durable materials that are hardened for handling abrasive fluids for long periods of time without wearing excessively.

How do they work?

There are a number of different types of slurry pumps. In the category of centrifugal pumps, they are typically a single stage end suction configuration. However, there are a number of unique features that distinguish it from more standard or traditional end suction pumps. They are often made of high nickel iron materials, which are extremely hard so that they minimize abrasive wear on the pump parts. This material is so hard that the parts often cannot be machined using conventional machine tools. Rather the parts must be machined using grinders, and the flanges have slots cast into them to accept bolts so that drilling holes into them isn’t required. As an alternative to hardened high nickel iron, slurry pumps may be lined with rubber to protect against wear. The choice of high nickel iron or rubber lining for this pump type is dependent on the nature of the abrasive particles in the slurry, their size, velocity, and shape (relatively rounded versus sharp and jagged).

In addition to being constructed of special materials, centrifugal slurry pumps often have replaceable liners on both the front side and back side of the casing. With some manufacturers these liners are adjustable while the pump is running. This lets minerals processing plants, which are often operated around the clock, adjust the pump’s impeller clearance without shutting down. Production levels remain high and the pump runs more efficiently.

In the category of positive displacement pumps, slurry pumps are often a type of diaphragm pump that uses a reciprocating diaphragm driven mechanically or by pressurized air to expand and contract the pumping chamber. As the diaphragm expands, slurry or sludge is drawn into the chamber through a valve that prevents backflow. When the diaphragm contracts, the fluid is pushed through the outtake side of the chamber. Other positive displacement types are piston pumps and plunger pumps.

Where are they used?

Slurry pumps are useful in any application in which fluids containing abrasive solids are processed. These include large mining, mine slurry transport, and minerals processing plants. In addition, they are used in sand and gravel dredging, and in plants that produce steel, fertilizers, limestone, cement, salt, etc. They are also found in some agricultural processing facilities and wastewater treatment plants.