Handling thick slurries: For transferring a solution containing a thick slurry (abrasive, solids-laden), which pump type is generally preferred?

Introduction / Context:
Thick slurries present challenges: high solids content, abrasiveness, and potential for clogging. The pump must tolerate solids, provide gentle handling, and often be capable of dry running or at least robust against suction issues.

Given Data / Assumptions:

• Fluid: thick slurry (suspension of solids in liquid).
• Abrasive particles likely present; viscosity elevated.
• Need: good solids-handling, non-shearing, clog-resistant flow path.

Concept / Approach:
Diaphragm pumps (air-operated double-diaphragm or mechanically driven) are widely used for slurries: they are positive displacement, have check valves that pass solids, can run at low speeds, and isolate the drive from the process fluid. They handle abrasives better than gear pumps and resist clogging more than tight-clearance rotary machines.

Step-by-Step Solution:
Match requirements to pump characteristics: solids tolerance and gentle action → diaphragm pumps.Eliminate options unsuitable for abrasives or high viscosity (e.g., gear pumps with tight clearances).Select diaphragm pump as the best general choice for thick slurries.

Verification / Alternative check:
Industrial practice favors diaphragm or peristaltic hose pumps for abrasive slurries; among listed options, diaphragm is the most standard answer for chemical/process plants.

Why Other Options Are Wrong:

• Reciprocating plunger: can handle pressure but suffers from valve wear and pulsation; less tolerant of large solids.
• Gear: tight internal clearances; poor for abrasive solids.
• Centrifugal: workable for some slurries with special designs, but thick slurries often require PD pumps.
• Peristaltic: also suitable but not provided as the main textbook choice in many question banks; diaphragm is more common.

Common Pitfalls:
Choosing gear pumps for slurries and damaging internals; oversizing centrifugal pumps leading to severe wear and low efficiency.

Final Answer:
Diaphragm pump (air-operated or mechanical)