Choosing the right type of wastewater pump will have a great impact on how well a pump will work, how long it will last, and how much time you’ll spend on maintenance.
For these reasons, understanding the popular pump types will help you to make an informed decision.
This article will go on to explore which pump types are often used with different applications. Whether you’re looking for a custom wastewater pump for a large sewage treatment plant (STP), industrial effluent water or a light commercial application, it helps to understand each pump type and how it’s best used.
What’s important to consider when choosing the right wastewater pump for South African conditions? We discuss local factors to keep in mind.
5 Pump types often used for wastewater
1. Centrifugal Pumps
How it works:
Operates using a rotating impeller to create centrifugal force, moving fluids efficiently through a piping system.
Best for:
Low-viscosity wastewater with minimal solids.
Applications:
Treated effluent transfer, moving clarified or treated wastewater between treatment stages.
2. Positive Displacement Pumps
How it works:
Moves a fixed volume of fluid per cycle by trapping and displacing it, making it ideal for high-viscosity fluids and precise flow applications.
Best for:
Highly viscous fluids and sludge.
Applications:
Sludge transfer, moving thick, viscous sludge in wastewater treatment plants.
3. Submersible Sewage Pumps
How it works:
Designed to operate while fully submerged in wastewater and handle raw sewage, sludge, and solids-laden wastewater with high efficiency and minimal clogging.
They use sealed motors and various impeller designs for efficiency.
Best for:
Commonly used for handling raw sewage, sludge, and solids-laden liquids.
Applications:
Municipal wastewater treatment plants, pumping raw sewage from collection pits to treatment processes.
Note: Centrifugal pumps and positive displacement pumps can be submersible, but not all of them are. Many centrifugal pumps are designed for dry installations.
4. Submersible Grinder Pumps
How it works:
Submersible pumps that include a grinding mechanism to macerate solid waste into a fine slurry before pumping.
Best for:
Used in residential, commercial and industrial applications.
Applications:
Residential sewage ejection, pumping sewage from homes located in areas with low-pressure sewer systems.
5. Wastewater Lift Pumps
How it works:
Designed to transport wastewater from lower to higher elevations.
Sealed waste water lift pump options to prevent leaks and ensure efficient operation.
Best for:
Often used in conjunction with wastewater pump stations.
Applications:
Residential sewage ejection, pumping sewage from homes located in areas with low-pressure sewer systems.
Choosing the right wastewater pump for South African conditions
Consider the following factors when selecting a waste water pump:
- Flow Rate and Head Requirements – ensures sufficient capacity.
- Solids Content and Size – determines the need for chopper or grinder pumps.
- Fluid Viscosity and Temperature – impacts pump performance and material selection.
- Installation Environment – factors such as space constraints and accessibility.
- Energy Efficiency – reduces operational costs.
- Maintenance Requirements – ensures long-term reliability.
- Local Regulations and Standards – compliance with South African wastewater guidelines.
About Ebara wastewater pumps - General Standards and Quality:
UNI EN ISO 9001:2015: Ebara pumps meet this international standard for quality management systems.
EU Waste Directive 2008/98/EC: Complaint with this EU directive for waste management.
Build Quality: Ebara pumps are known for their robust construction and quality materials.
Get the best wastewater pump for
your project:
In South Africa, we have a limited supply of electricity and water.
Less efficient pumps will use more electricity than they should. For this reason, you need to get the most efficient pump for your specific application.
Not only will you use less electricity, but the pump will last longer, because it’s not under- or over-working.
How do you get the most efficient pump for what you want to do? Discuss your project and specifications with an experienced engineer at a pump company.
Next Steps:
Find out more about sewage pump stations
For an in-depth look at sewage pump stations in South Africa, read this project report by the Water Research Commission, “Understanding Sewage Pump Stations” at this link: https://www.wrc.org.za/wp-content/uploads/mdocs/TT%20627-15.pdf
Also see “Examples of Completed Water Infrastructure Projects” here: https://ebara.co.za/infrastructure/
Ask an Experienced Engineer
To consult with our Engineer, who has specialised knowledge of wastewater pumps, please ask your questions here.