--- title: "Wastewater Treatment Pumps: Types, Applications, and Selection" date: 2026-06-06T01:00:00Z modified: 2026-06-11T01:31:03Z permalink: "https://www.defucc.com/blog/sewage-pump/wastewater-treatment-pump-types/" type: post status: publish excerpt: "" wpid: 2486 categories: - sewage pump featured_image: "https://www.defucc.com/wp-content/uploads/2026/06/image-13.webp" featured_image_alt: What Type of Pump Is Used in Wastewater Treatment timestamp: 2026-06-11T01:31:03Z tags: - sewage pump --- Centrifugal pumps are the main type used in wastewater treatment. Lift stations run on them. So do grit removal and effluent discharge. Positive displacement and diaphragm pumps handle the jobs centrifugals aren’t built for, like moving thick sludge or metering corrosive chemicals. ## How Does a Wastewater Treatment Pump Work? Centrifugal and positive displacement work differently, and that difference matters when you’re picking equipment. A centrifugal pump has an impeller spinning inside a casing. Wastewater comes in through the center, the vanes throw it outward, and the casing turns that motion into pressure. Raw sewage clogs standard closed impellers, so most municipal systems run vortex or semi-open designs instead. Vortex impellers stay out of the flow path and pull solids through with a whirlpool effect. Semi-open impellers let stringy material slide past rather than wrap around. Positive displacement pumps do something else entirely. They trap liquid in a chamber and push it forward. Progressive cavity and diaphragm pumps both work this way. Flow rate doesn’t change with the fluid’s composition, making them good for sludge transfer and chemical dosing. ## **What Are the Main Types of Wastewater Treatment Pumps?** The pump you need depends on its location in the process. ### Self-Priming Centrifugal Pumps A pump mounted above the wet well has to draw fluid up through the suction line. Standard centrifugals won’t do that because they can’t clear air. Self-priming pumps hold liquid in the casing between runs, mix it with incoming air on startup, vent the air out, and then shift into normal operation. DEFU’s[ TX/TH self-priming sewage pumps](https://www.defucc.com/product/tx-th-series-water-pump-self-priming-sewage-pump/) open at the non-drive end. The suction cover comes off completely, so you can check the impeller, wear rings, and seals without touching the piping. Flow goes up to 1,021 m³/h, whereas solids can handle up to 76m at a time. ### Submersible Pumps Submersibles are submerged in the wet well. The motor is sealed and bolted to the pump body. No suction lift to worry about, and less cavitation because the water around the inlet keeps pressure positive. The tradeoff is access. Maintenance means pulling the pump out of the well, which takes more time and equipment than working on a surface-mounted unit. Lift stations use submersibles when there’s no room for surface-mounted equipment or when the wet well shape makes it the simpler option. ### Positive Displacement Pumps [Centrifugal pumps](https://www.defucc.com/wp-content/uploads/wp-mfa-exports/post/what-is-a-sewage-centrifugal-pump.md) lose efficiency as the fluid thickens. Positive displacement pumps don’t. They push a fixed volume forward each cycle, regardless of backpressure. Progressive cavity pumps move biological sludge through transfer lines. [Diaphragm pumps](https://www.defucc.com/wp-content/uploads/wp-mfa-exports/post/diaphragm-pump-technology-guide.md) meter corrosive chemicals. Both can run dry without wrecking the seals. ## **What Are the Best Wastewater Treatment Pumps for Municipal Treatment Plants?** Choosing the best wastewater Treatment pumps for municipal treatment plants means knowing what each part of the process throws at the equipment. | **Treatment Stage** | **Pump Type** | **What Matters** | | --- | --- | --- | | Inflow / Lift Stations | Self-priming or submersible centrifugal | Solids clearance, anti-clog impeller | | Grit Removal | Hardened end-suction centrifugal | Abrasion resistance, replaceable wear plates | | Sludge Transfer | Progressive cavity or lobe pump | Consistent flow through thick solids | | Chemical Dosing | Air-operated diaphragm | Chemical resistance, precise metering | | Effluent Discharge | Standard end-suction centrifugal | High flow, low energy cost | DEFU’s [DJ Series self-priming pumps](https://www.defucc.com/product/dj-series-self-priming-centrifugal-sewage-pump/) pass 76mm solids at 468 m³/h. Wear plates adjust from the outside, so you restore clearances during maintenance without pulling the pump apart. Our [DA end-suction pumps](https://www.defucc.com/product/da-end-suction-centrifugal-pump/) share dimensions with Cornell equipment. You can integrate them into existing setups without reworking piping or supports. Learn more in our [sewage pump application guide](https://www.defucc.com/wp-content/uploads/wp-mfa-exports/page/sewage-pump.md). [![TX/TH Series Water Pump Self Priming Sewage Pump](https://www.defucc.com/wp-content/uploads/2026/06/666.webp) ](https://www.defucc.com/product/tx-th-series-water-pump-self-priming-sewage-pump/)TX/TH Series [![DJ Series Self-Priming Centrifugal Sewage Pump](https://www.defucc.com/wp-content/uploads/2026/06/777.webp) ](https://www.defucc.com/product/dj-series-self-priming-centrifugal-sewage-pump/)DJ Series [![DA End Suction Centrifugal Pump](https://www.defucc.com/wp-content/uploads/2026/06/888.webp) ](https://www.defucc.com/product/da-end-suction-centrifugal-pump/)DA End Suction Centrifugal Pump ## **What Affects Wastewater Treatment Pump Lifespan?** Wastewater treatment pump lifespan runs 10 to 15 years. Abrasion, corrosion, and cavitation are what take pumps out early. ### Abrasion and Grit Sand and debris grind impeller vanes down over time. Clearances widen and efficiency drops. The pump draws more power to move the same volume, and energy costs go up. Externally adjustable wear plates let you tighten clearances during maintenance instead of replacing the housing. DEFU’s DJ Series has this. ### Chemical Corrosion Hydrogen sulfide, industrial runoff, and extreme pH eat through cast iron. If the effluent is aggressive, stainless steel lasts longer. Duplex alloys like CD4MCu hold up even better in harsh conditions. Our [JT/JU non-clog pumps](https://www.defucc.com/product/jt-ju-sellf-priming-sewage-pump/) are available in stainless steel, including SS316L for harsh conditions. Dimensions match Gorman-Rupp T/U series, so you can swap them into existing setups. ### Cavitation Operating too far from the best-efficiency point creates vapor bubbles that collapse onto metal surfaces. Impeller pitting comes first, then seal failure. Size the pump correctly to avoid this. Add static lift to friction losses from your piping and check that the total dynamic head is against the pump curve. Net positive suction head available has to exceed what the pump needs, or you’ll have problems later on. Silicon carbide and tungsten carbide seals prevent contaminated fluid from entering the motor. Standard on DEFU’s TX/TH Series. ## **Find the Right Pump for Your Plant** Raw sewage at the inlet doesn’t look anything like clarified effluent at discharge. Solids content changes. So do viscosity and chemical exposure. Each stage needs a pump that can handle those conditions. DEFU pumps share dimensions with Cornell and Gorman-Rupp. Replacement is straightforward. Parts sourcing stays simple no matter where you’re operating. The self-priming units evacuate air on their own and still pass large solids. Access covers open up so you can get to the internals without pulling piping apart. If you’re replacing old equipment or specifying pumps for a new build, dimensional compatibility cuts lead time. It also keeps installation costs down. [Contact us today](https://www.defucc.com/wp-content/uploads/wp-mfa-exports/page/contact.md) to discuss your pump requirements or go over your project details. [Get Free Quote](https://www.defucc.com/wp-content/uploads/wp-mfa-exports/page/contact.md)