Industry Popularization | Application of Centrifugal Pumps in Sewage Treatment: Principles, Scenarios and Selection Key Points

The centrifugal pump relies on the centrifugal force generated by the high-speed rotation of the impeller to suck in the liquid and pressurize it for discharge, thus achieving continuous transportation. It holds a dominant position in the field of wastewater treatment, mainly due to three advantages:
1. High flow rate and stable operation: Most wastewater treatment processes involve large flow rates and continuous operation conditions, and the centrifugal pump's structure is naturally suitable for such scenarios.
2. Simple structure and easy maintenance: There are no complex reciprocating components, and easily damaged parts (such as the impeller and seals) can be replaced quickly, resulting in short downtime.
3. Strong adaptability to media: By selecting wear-resistant and corrosion-resistant materials and structural forms, it can handle wastewater containing solids, sand, and corrosive substances.

Inflow lifting and transportation
The first process in a sewage treatment plant is usually the **lift pump station** - using centrifugal pumps to lift the gravity-flow sewage to the subsequent treatment units. In municipal scenarios, **submersible sewage pumps** are commonly used, as the equipment is placed underwater, occupies a small area, and has low noise.
2. Biochemical Treatment and Recirculation
In processes such as A²/O and oxidation ditch, **sludge return pumps and mixed liquid return pumps** are needed to maintain microbial concentration and the effectiveness of nitrogen and phosphorus removal. These pumps usually require no clogging and good wear resistance.
3. Sludge Concentration and Dewatering Feed
The residual sludge discharged from the secondary sedimentation tank has a high solid content and is highly abrasive. During transportation, extremely high requirements are placed on its **wear resistance** - this is precisely the scenario where high-chromium alloy slurry centrifugal pumps (such as the AH high-chromium slurry pump of CZME, with the flow components made of high-chromium white cast iron) come into play.
4. Industrial wastewater and special media
- Power plant desulfurization wastewater: Contains chloride ions and has large pH fluctuations, requires corrosion-resistant pumps - corresponding to desulfurization pumps (Desulfurization Pump).
- Mining/sorting wastewater: Contains a large amount of abrasive solid particles, requires heavy-duty slurry pumps and centrifugal mining pumps.
- River channels/soil erosion silt: High in solids content, commonly uses dredging pumps.

CZME's factory is equipped with 126 main production equipment and 34 specialized units, covering the entire process of casting, heat treatment, precision machining, assembly and performance testing. The flow components are made of high-grade wear-resistant materials (such as Cr27 high-chromium alloy impellers, with hardness ranging from HRC 58 to 62), and the hydraulic model is optimized through CAD/CAE/CFD simulations. The monthly casting capacity reaches several thousand tons. The products have obtained the **ISO 9001** and **CE certifications**.

The selection is based on three key factors:
- Flow (Q) and Head (H): Determined based on the designed water volume and lifting height.
- Material properties: Solid content rate, particle size, pH, temperature determine the material and structure (such as whether it needs to be non-clogging, wear-resistant, or corrosion-resistant).
- Installation conditions: Dry/wet installation, space, power supply method.
Three things for operation and maintenance:
1. Regular inspection of wear parts: The impeller, seal, and bearing are the key points. Replace them in time if they are worn out.
2. Avoid dry running and cavitation: Ensure the inlet liquid level and pipeline sealing to extend the service life.
3. Establish spare parts inventory: CZME provides emergency spare parts response within 48 hours and on-site training, which can significantly improve equipment availability.

Centrifugal pumps are the "heart power" of wastewater treatment. From municipal elevations, biochemical reflux, to sludge transportation and industrial special wastewater, different working conditions require matching centrifugal pumps of different structural forms. "On-demand selection + Wear-resistant material + Standard operation and maintenance" is the key to the stable and low-consumption operation of wastewater treatment plants.
As a manufacturer specializing in high-wear condition pumping solutions, CZME continuously provides its customers in the fields of mining, environmental protection, water conservancy and municipal water treatment with high-performance slurry pumps, submersible pumps, desulfurization pumps, and dredging pumps.

Regarding Ningbo CZ Mining Energy Co., Ltd. (CZME)
CZME is a Chinese enterprise specializing in the research and manufacturing of industrial pumps for high wear conditions. Its products include a full range of industrial pumps and accessories such as slurry pumps, dredging pumps, submersible pumps, mobile pump trucks, multi-stage centrifugal pumps, and desulfurization pumps. The company is located in Beilun District, Ningbo City, Zhejiang Province. It possesses complete capabilities in casting, heat treatment, machining, assembly, and testing. It has obtained ISO 9001 certification and CE certification, and its service network covers 100+ countries and regions around the world. The official website supports over 50 languages.
Contact Us

- 📞 +86 173 0312 7762

- 📧 info@czmemining.com
- 🌐 https://www.czmemining.com