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The flow rate of concentrated sludge from water treatment plants is generally not high; the sludge has a high concentration and contains fine particles. When air flotation is used in the concentration process, the sludge contains a large number of bubbles. To improve sludge dewatering efficiency, flocculants are often added; to prevent the flocs from being damaged, high-speed rotation or significant shear forces should be avoided during transportation. Additionally, the selection of the sludge pump should also be appropriate for the type of dewatering machine. For example, when a plate and frame filter press is used, the pressure during the sludge feeding process increases from low to high, while the flow rate decreases from high to low. Based on the current usage of different pump types, centrifugal pumps are widely used, but they exert a high shear force on the fluid being transported. Diaphragm pumps are commonly used in corrosive media and dosing systems. Plunger pumps are expensive and are mostly used in situations where very high pressure is required. Screw pumps and cam rotor pumps are capable of transporting the medium in a continuous and uniform manner, without turbulence, agitation, pulsation, or shear effects. They are particularly suitable for pumping concentrated sludge, as they help to maintain the properties of the sludge to the greatest extent possible and prevent the flocs from being damaged, thereby achieving optimal dewatering results. Therefore, screw pumps or cam rotor pumps are suitable for concentrating the sludge from wastewater treatment plant effluents. In the sludge treatment systems of water treatment plants, screw pumps are usually eccentric single-screw pumps, which consist of components such as a stator, rotor, universal joint, drive mechanism, and frame. Due to the different numbers of threaded ends on the rotor and stator, a closed volume chamber is formed between their surfaces. The sludge within this chamber is pushed axially toward the sludge discharge port as the rotor rotates, thereby continuously transporting the sludge from the intake end to the discharge end. There is continuous interference fit between the rotor and stator of the screw pump, which creates a reliable sealing line between the suction side and the discharge side; as a result, the screw pump is able to handle high pressures and also possesses a certain degree of self-priming capability. Single-screw pumps can be used to transport liquids containing solid particles, as well as acids, alkalis, and salts, and liquids of different viscosities such as pulp, ointments, dirty oil, sewage, slurry, and jam. They are widely applied in industries such as environmental protection, bioengineering, sewage treatment, mining, petrochemicals, food processing, sugar production, pharmaceuticals, papermaking, dyes, construction, agriculture, and other industrial sectors. The cam rotor pump is also a type of positive displacement pump; its working principle is similar to that of a Roots blower. Two rotor impellers are arranged parallel to each other, and chambers are formed between these two impellers as well as between the rotors and the pump casing. As the rotors rotate in coordination, sludge is drawn in and discharged, thereby enabling the transport of sludge. Rotor impellers come in configurations with 2 blades, 3 blades, 4 blades, and 6 blades, etc. As Zibo’s first e-commerce industry base for physical enterprises, the China Pump Industry Network (by.99114.com) selects and supports a number of local pump manufacturers in creating e-commerce platforms for their specific products, with the aim of facilitating B2B online transactions for all customers in the pump industry.