 | Tools for Mining: Techniques and Processes for Small Scale Mining (GTZ, 1993, 538 p.) |
 |  | Technical Chapter 4: Water supply and drainage |
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4.5 Pneumatic high-pressure pump
Deep Mining General
Underground Mining Mine
Drainage
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germ.: |
Pneumatische Forder- und Hochdruckpumpe |
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span.: |
bomba neumatica de transporte y de alta presion, bomba neumatica de alta presion |
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Producer: |
Atlas Copco, Pleiger |
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TECHNICAL DATA: | |
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Dimensions. |
40 × 40 × 60 cm LWH |
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Weight: |
25 - 50 kg |
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Form of Driving Energy: |
pneumatic |
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Alternative Forms: |
none |
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Mode of Operation: |
centrifugal pump, diaphragm pump or multistage piston pump |
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Operating Materials: |
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Type: |
compressed air (6 bar) |
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Quantity: |
2 - 4 m³/min |
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ECONOMIC DATA: | |
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Operating Costs: |
mainly cost of energy |
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Related Costs: |
compressed air feed line, transport line (fire hose or pipe) |
CONDITIONS OF APPLICATION:
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Operating Expenditure: |
low |————|————| high |
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Maintenance Expenditure: |
low |————|————| high |
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Location Requirements: |
no restrictions, however pump selection must consider water quality: centrifugal pump and diaphragm pump for waste water; centrifugal pump for fresh water |
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Replaces other Equipment: |
other pump and water conveying systems |
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Regional Distribution: |
worldwide |
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Operating Experience: |
very good |————|————| bad |
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due to low specific weight and non-susceptibility to malfunctions |
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Environmental Impact: |
low |————|————| very high |
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minimal oil contamination from the air compressor |
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Suitability for Local Production: |
very good |————|————| bad |
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Lifespan: |
very long |————|————| very short |
OPERATING PRINCIPLE:
For drainage in underground mines, a wide range of different pumps are available as pneumatic pumps which can be operated with the commonly used underground energy source compressed air.
Depending on the type of fluid to be conveyed and the transport distances and quantities, axial, radial, piston or diaphragm pumps can be employed. The first two of these pump types are fluid-flow engines, which transmit energy to the water through acceleration. The resulting lifting pressure is sufficient for only small to moderate lifting distances, the rate of flow is however relatively high. The positive-displacement pumps (piston and diaphragm pumps) expel the water from the pump chamber by decreasing the volume. High pressures are attainable especially with piston pumps.
AREAS OF APPLICATION:
Pneumatic pumps are employed both in underground and surface mining for drainage purposes, for the supply of hydraulic fluids, for pumping of gelatinous blasting explosives, etc.
REMARKS:
Fluid-flow engines serving as pumps are generally not equipped with check valves, so that the water in the transport line flows back down when the power is turned off. Piston pumps, on the other hand, are inherently designed with check-valves, so that the return flow of water through the pump is not possible.
Piston and diaphragm pumps can also function as suction pumps whereby the maximum suction head should not exceed 5 m.
In mines where a compressed air infrastructure does not exist (rendering pneumatic pumps infeasible), electric pumps and even pumps driven by internal-combustion engines are also available. They are, however, inferior to compressed air pumps in terms of operating safety.
SUITABILITY FOR SMALL-SCALE MINING:
For pneumatically mechanized mining operations, compressed air pumps are mobile and universally employable as a result of their high safety of operation, low specific weight and sturdy technology.
Fig.: Cross-section of a pneumatic
immersion pump for drainage purposes. Source: Manufacture's information,
Pleinger
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