Slurry pumps: operating at the extremes
Slurries are generally characterised as abrasive, viscous – sometimes also corrosive – liquids that are high in solids and quick to settle. These characteristics mean more energy is required to pump slurries than is needed for clean water. Slurries also expose pumps for substantially higher levels of wear. Beyond these generalities, however, slurries vary widely, even within the same mining or mineral processing operation, based on the specific application.
When selecting a slurry pump for a mining or mineral processing application, key factors therefore include:
- Long and predictable wear life to reduce downtime and the number of shutdowns
- High efficiency for reduced energy consumption
- Ease of maintenance and adjustments to protect workers from hazards
- Quick and reliable availability of high-quality spare parts
Centrifugal pumps for slurry applications
Centrifugal pumps have a long history of use in slurry applications and are commonly used for slurry handling in mining and mineral processing operations today. As the name suggests, these pumps generate centrifugal force via the rotation of an impeller, which is transferred as kinetic energy into the slurry to move the liquid through the pump.
When selecting a centrifugal pump for slurry handling, there are a wide range of additional factors that go into ensuring an appropriate pump design for the application. These include the size and design of the impeller (which must allow passage of solids through the pump); type of shaft seal; casing design; and choice of materials.
Given the complexities involved, it is important to work with an expert supplier, who understands the particular process challenges and can provide the most appropriate pump type and model for the job.
The innovative wear ring assembly: redefining centrifugal slurry pumps
A key technological milestone in the history of centrifugal slurry pumps was the development of the patented wear ring assembly for KREBS® millMAX™ slurry pumps. This innovation completely transformed the slurry pump industry and continues to be the defining factor that sets KREBS pumps apart from their competitors.
The wear ring assembly is a proprietary suction-side sealing system, which incorporates a wear ring, wear ring carrier, and wear ring adjustment bolts. By allowing the suction-side gap to be closed when the pump is running, the wear ring eliminates two of the major issues faced by conventional slurry pumps: mechanical grinding of solids between the suction liner and the impeller; and flow recirculation to the impeller eye on the suction side.
