Pumps for Pumping Viscous Fluids

Viscous fluids are liquids that have a thick and sticky consistency, such as heavy oils, slurries, and pastes. These fluids require specific types of pumps that can handle their high viscosity and provide efficient pumping. Among the options provided, the correct answer is option 'B' - Screw pump. Let's understand why screw pumps are suitable for pumping viscous fluids.

Screw Pump
- Screw pumps, also known as progressive cavity pumps or eccentric screw pumps, are positive displacement pumps that are designed to handle viscous fluids.
- These pumps consist of a helical rotor and a stator. The rotor has a single-threaded helical shape, while the stator has a double-threaded helical shape.
- As the rotor turns within the stator, cavities are formed between the rotor and stator. These cavities progress from the suction side to the discharge side, trapping and moving the fluid.
- Due to their design, screw pumps can handle fluids with high viscosity, ranging from low to extremely high. They can pump fluids with viscosities up to 1,000,000 centipoise.
- Screw pumps are capable of handling solids and abrasive materials present in the fluid without causing damage to the pump or affecting its performance.
- These pumps provide a smooth and non-pulsating flow, which is essential for applications where a consistent and continuous flow is required.
- Screw pumps have a high suction capability, enabling them to draw viscous fluids from tanks and reservoirs effectively.
- They are commonly used in various industries, including oil and gas, wastewater treatment, chemical processing, food and beverage, and pharmaceuticals.

Other Pump Options
- Centrifugal pump: Centrifugal pumps are primarily used for pumping low to medium viscosity fluids. They rely on centrifugal force to move the fluid and are not suitable for handling highly viscous fluids efficiently.
- Reciprocating pump: Reciprocating pumps use a piston or plunger to create a reciprocating motion, which results in the pumping action. While they can handle viscous fluids, they are more commonly used for high-pressure applications.
- Jet pump: Jet pumps operate based on the principle of fluid entrainment. They are not specifically designed for pumping viscous fluids and are more commonly used for applications such as lifting water from wells.

Conclusion
When it comes to pumping viscous fluids, screw pumps are the most suitable choice. Their positive displacement design, ability to handle high viscosity, and capability to handle solids make them ideal for such applications. Other pump options like centrifugal pumps, reciprocating pumps, and jet pumps are better suited for pumping low to medium viscosity fluids or for specific applications.