Air lifting in borehole drilling requires specific equipment to efficiently remove cuttings, sediment, and debris from the borehole using compressed air. This setup is straightforward yet robust, commonly used in water well development in regions like Kenya.
Core Equipment
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Air Compressor: A high-capacity unit, typically 150-185 CFM (cubic feet per minute) at 100-200 PSI, powers the process by injecting compressed air. Oil-free models prevent groundwater contamination.
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Riser Pipe (Hollow Stem or Eductor Pipe): 2-3 inch diameter PVC, steel, or HDPE pipe, long enough to reach the borehole base. It serves as the conduit for the air-water-slurry mixture to rise.
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Air Hose/Line: Reinforced high-pressure hose (1-1.5 inch diameter) connects the compressor to the riser pipe’s lower end, often via a side inlet or whip line.
Auxiliary Components
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Discharge Hose: Flexible hose attached to the riser’s top directs the expelled mixture to a settling pit or tank, preventing surface mess.
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Plenum or Eductor Assembly: Optional but effective for large bores; includes a tapered discharge horn, diffusion ring, and transition pipe to optimize air injection and flow velocity.
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Valves and Fittings: Pressure regulators, ball valves, and quick-connect couplers control air flow and allow valve closure for wall scrubbing.
Support and Safety Gear
This equipment ensures thorough cleaning, with the compressor driving buoyancy for efficient debris lift. For Kenyan operations, portable truck-mounted compressors from brands like Atlas Copco suit coastal geology
