Why Do I Need A Slurry Pump?

What makes slurry pumps special?

Slurry pumps can withstand extensive wear due to characteristics such as: a large impeller diameter, shafts, bearings, and internal passageways as well as heavy-duty construction. On an industrial level, slurry pump features generate higher upfront and operational costs compared to water pumps. However, only slurry pumps can hydrotransport solid materials efficiently, and the long-term benefits outweigh initial costs.

Key to slurry pump success is the generation of centrifugal force, which pushes material outward from the pump center. This contrasts with centripetal force, which pushes material toward the center. Slurry pumps must operate on centrifugal principles because the forces that impart velocity to the slurry accelerate the transport process. A centripetal pump, on the other hand, would be impractical since the solids within the slurry would accumulate instead of flowing freely.

Slurry pump installations

Knowing these basics, it’s also important for anyone looking to install a slurry pump to understand the specific environments required for each type of pump. Three types of slurry installations exist:

• Wet — In this installation, the slurry pump and drive are fully submersible. This is necessary for certain slurry pump applications, such as underwater operations.
• Dry — In this installation, the pump drive and bearings are kept out of the slurry. The wet end — which includes the shell, impeller, hub or suction liner, and shaft sleeve or stuffing box — is free-standing and clear of any surrounding liquid. Slurry pump technicians install most horizontal pumps this way.
• Semi-dry — This special arrangement is used for dredging applications with horizontal pumps. Operators flood the wet end and bearings but keep the drive dry. Bearings require special sealing arrangements in this case.

Slurry pumping considerations

Those with experience pumping slurries know it's not an easy task. Slurries are heavy and difficult to pump. They cause excessive wear on pumps, their components, and are known to clog suction and discharge lines if not moving fast enough.

It’s a challenge to make slurry pumps last for a reasonable amount of time. But, there are a few things you can do to extend the life of your slurry pump and make pumping slurry less of a challenge.

• Find the sweet spot that allows the pump to run as slow as possible (to reduce wear), but fast enough to keep solids from settling and clogging the lines.
• To reduce wear, lower the pump’s discharge pressure to the lowest point possible
• Follow proper piping principles to ensure a constant and uniform delivery of the slurry to the pump.
• Pumping slurries poses several challenges and problems, but with proper engineering and equipment selection, you can experience many years of worry-free operation. It's important to work with a qualified engineer when selecting a slurry pump because slurries can wreak havoc on a pump if not properly selected.

The last words

Although this guide provides an overview of slurry pumps and their installations, there’s plenty more to learn. For those who want to better understand slurry pumps and their applications or need help deciding which pump and installation type is best for their applications, KATI is here to help.