摘要 |
<p>Apparatus of the coil pump type is used to effect substantial purifying effect upon the pumped liquid. This is achieved by increasing the surface area, within the bore and available for contact by the liquid, to a value substantially above what would be normal practice if the apparatus were being used simply as a pump. The increased surface area may e.g be provided by anchored filaments or by buoyant granules held captive within compartments defined by baffles which restrain the granules but allow liquid to pass. The invention includes arrangements of the inlet and outlet of a coil pump, and arrangements by which both the gaseous and the liquid products of the apparatus may be used to exert a purifying action upon the body of liquid from which the pump is drawing.</p> |