Why Pumps and Mixers Must Be Engineered For Wastewater Treatment

In municipal wastewater treatment, pumps and mixers are selected, specified, installed, and maintained as separate pieces of equipment. Pumps move wastewater and sludge. Mixers keep solids suspended and assist in the biological processes. On paper, they appear to perform different jobs.

In reality, pumping and mixing are closely connected. When these systems aren’t engineered specifically for wastewater treatment, they experience issues from rags and grit. Impellers/propellers not designed specifically for the stringy material in wastewater tend to collect them instead of passing them—leading to solids buildup, ineffective biological processes, increased energy consumption, and higher maintenance costs. Impellers not designed and selected for grit experience excess wear and suffer from decreased performance.

Pumps Convey the Toughest Wastewater

KSB ARX and KRT submersible wastewater pumps are engineered specifically for wastewater applications. Non-clog impellers are designed specifically for stringy material and various metallurgy provide options for abrasive materials. KSB pumps provide high efficiency and reliable performance while minimizing maintenance and downtime.

Key features that support wastewater treatment applications include:

• Non-clog impeller designs that are designed specifically for wastewater
• Robust construction built for continuous-duty operation
• Cooling and sealing systems designed for the toughest applications
• Hydraulic efficiency to reduce energy consumption

Mixing Keeps the Process moving

Lift Stations benefit from mixers keeping to Fats, Olis & Greases (FOG) suspended and not collecting on the top of the water/walls. Biological treatment depends on maintaining consistent conditions inside basins and tanks. Anoxic Zones need mixing and conveyance for the De-nitrification to occur effectively. KSB mixers are designed to excel these applications.

When mixing is inadequate, several problems begin to appear:

• Dead zones form, where solids settle and biological activity slows.
• Uneven nutrient distribution affect treatment performance.
• Buildup increases and cleaning/maintenance requirements increase.

Effective mixing ensures that solids stay suspended, biological activity remains consistent, and flows remain predictable throughout the process. KSB submersible mixers are designed specifically for wastewater treatment environments. Their robust construction, optimized propeller design, and ability to deliver reliable mixing energy help prevent solids settling and maintain stable basin conditions.

But mixing alone isn’t enough. The pumps responsible for moving sludge and return flows must be equally suited to the application.

Why Pumping and Mixing Must be designed for Wastewater

When pumps and mixers are not engineered specifically for wastewater, systems often develop hidden operational problems. These hidden problems typically result in emergency maintenance and repairs which are much more costly.

When pumping and mixing are designed for wastewater, several benefits emerge:

• Improved solids suspension and transport
• Reduced clogging and pump wear
• More effective biological treatment
• Lower energy consumption
• Less reactive maintenance

This systems-level approach is increasingly important as wastewater conditions become more challenging, maintenance staffs are getting smaller and municipalities work to improve operational efficiency.

The Role of Local Expertise

Selecting the right pump or mixer is only part of the solution. Ensuring that the equipment performs reliably in a real wastewater system requires application knowledge, technical assistance, maintenance training, and long-term service support.

As the authorized KSB Service and Support partner in Wisconsin and the Upper Peninsula of Michigan, Crane Engineering works closely with municipalities, utilities, consulting engineers, and contractors. Crane Engineering will evaluate conveyance and treatment systems and recommend equipment designed for long-term reliability. From equipment selection to operation, Crane Engineering is there to help pumps and mixers perform as intended throughout the life of the unit.

Equally important, Crane Engineering’s service technicians are factory-trained on KSB equipment, providing the confidence that the pumps and mixers are supported by people who understand the technology and its applications. This training allows our team to provide reliable maintenance, troubleshooting, and long-term service support for wastewater facilities.

Building More Reliable Treatment Systems

Reliable wastewater treatment doesn’t depend on a single piece of equipment. It depends on systems designed to work together. When pumping and mixing are selected, provided and supported by experienced local partners that understand the entire wastewater process —municipal utilities can improve treatment, reduce maintenance, and extend equipment life.

By combining KSB’s proven wastewater technologies with Crane Engineering’s expertise and service support, municipalities gain a partner focused on keeping treatment systems operating reliably today and well into the future.