What Are The Best Pumps For Industrial Water Treatment
When it comes to the best pump for industrial wastewater treatment there is no one-size-fits-all. The right pump for your industry’s purpose depends on the fluid’s characteristics, particular flow rate, pressure, distance and height differential that applies. Managing industrial water treatment is a complex process at the best of times but having the right pump can increase efficiency and minimise downtime for repairs. Here we explore the different pumps available for water treatment.
Centrifugal Pumps
Centrifugal pumps have an impeller that rotates within a casing “throwing” water away from the central inlet. Wastewater enters the pump through a suction inlet and the impeller’s rotation pushes the water out using centrifugal force. Within the Centrifugal pump category, there are those optimised for “clean water” and those built for slurries and fluid containing abrasive solids, such as SlurryPro. These have more open impellers and are built from abrasion-resistant materials.
Centrifugal pumps are highly efficient at displacing high volumes of wastewater while their straightforward design involves fewer moving parts, resulting in less maintenance and simpler operation. They are cost-effective to buy, can handle a range of applications and are suitable for situations where there is a continuous flow of fluid.
Centrifugal pumps are either ‘dry-sited’ or submersible. Most dry-sited centrifugals are known as “End Suction Pumps” which discharge the water at a 90-degree radial angle to its inlet direction. A downside to these is they have poor suction lift capabilities, so they may require priming to flood the chamber before use.
Submersibles are generally centrifugal types that send the water out in an axial direction, i.e. they suck the fluid at the bottom of the pump and discharge it vertically out of the top.
There is also a type of end suction centrifugal pump which is arranged in a vertical alignment, where the motor sits above the water level and the pump chamber below it. These are often referred to as ‘semi-submersible’ and overcome the priming weakness.
Centrifugal pumps are best suited for low-viscosity fluids and watery slurries or in situations where high-volume pumping is required.
Submersible Pumps
Submersible pumps sit in the fluid they are pumping making them ideal for dewatering pits, sumps and lagoons. As they hang below the surface there’s no need to prime them either. When the pump operates, the impeller rotates and creates a flow of water or wastewater through the pump and into the discharge pipe.
Their close proximity to the fluid they’re pumping makes them very efficient with minimal energy loss and a reduced risk of cavitation. They’re also compact and operate quietly but maintenance access can be more difficult and continuous exposure to water can lead to corrosion.
Positive Displacement Pumps
Positive displacement pumps trap a fixed amount of fluid and force (displace) that volume into the discharge pipe. They create a vacuum that draws fluid into an enclosed chamber. Once inside, mechanical forces push it to the discharge side which ensures a consistent level of fluid is moved during each cycle regardless of system pressure.
They are adept at handling highly viscous industrial wastewater such as thick sludge and are often self-priming. Some are capable of handling fluids with suspended solids or abrasive particles without significant wear and are ideal for a variety of industrial processes such as chemical dosing, moving slurries and sludge dewatering.
They are less efficient at handling low-viscosity, high-volume fluids and can be more expensive than centrifugal pumps. They are also more complex and may require a higher level of maintenance.
There are a wide variety of positive displacement pump types, including ram, diaphragm, lobe, progressive cavity, and peristaltic pumps.
Industrial Peristaltic Pumps
Industrial peristaltic pumps are a type of positive displacement pump that uses rotating rollers to imitate a peristaltic process to push or squeeze fluid along a flexible tube. This action of pushing it forward creates a vacuum which draws more fluid into the tube.
The fluid never meets the pump other than in the interior of the tube. This self-contained design helps avoid contamination or damage elsewhere and is ideal for handling corrosive, viscous or abrasive fluids. The absence of seals or valves reduces the risk of breakages while the pump allows for highly precise flow and metering, ideal for accurate chemical dosing in wastewater treatment.
However, their initial cost can be higher than simpler pumps and while they’re great for moderate pressures, they’re less effective with higher pressures and flow rates.
Progressive Cavity Pumps
These are another type of positive displacement pump with a helical rotor that rotates in a stator. As it rotates it forms a sealed cavity between itself and the stator drawing liquid from the inlet to the discharge side.
The original PC pumps were designed for smooth pastes typically found in manufacturing applications, but specially engineered Toro-Kronoa PC pumps have been designed for sewage and wastewater sludge applications.
These robust pumps offer continuous, low pulse flow and handle viscous and abrasive fluids extremely well - ideal in industrial wastewater treatment. They can self-prime and are effective at pumping even when air is in the suction line. The Toro-Kronoa T-Line pump is generally lower maintenance than standard PC pumps, with large inspection ports and the ability to replace worn stators in situ to minimise downtime. From material selection, and geometry, to the construction methods used, the pump designers have overcome many traditional issues that PC pumps are notorious for.
It’s essential you choose the right pump for each of your water treatment processes but with so many choices it can be hard to know what the best option is. Our experts are on hand to guide you through the process and help you decide the most effective option for your operations.
Find out more with our Industrial Dirty Water Pump Selection Guide
