Rapid sand filtration is a purely physical drinking water purification method. Rapid sand filters (RSF) provide rapid and efficient removal of relatively large suspended particles. Two types of RSF are typically used: rapid gravity and rapid pressure sand filters. For the provision of safe drinking water, RSFs require adequate pre-treatment (usually coagulation-flocculation) and post-treatment (usually disinfection with chlorine).
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moving, proceeding, or acting with great speed after a whirlwind romance of only a few weeks, the couple decided to get married Synonyms blistering, breakneck, breathless, brisk, dizzy, fleet, fleet-footed, flying, galloping, hasty, hot, lightning, nippy, quick, rapid, rapid-fire, rattling, snappy, speedy, splitting, swift, fast, zippyRelated Words ...