Compact biofilter for drinking water treatment

A slow rate filtration system for removing bacteria, viruses, algae, Giardia cysts, turbidity and other impurities in raw water supplied to a home or the like to provide suitable drinking water, said system comprising:

• a sealed container divided into an upper and a lower chamber by support means, said support means supporting thereon a quantity of filter material sufficient for removing undesired bacteria, viruses, algae, Giardia cysts, turbidity and other impurities from the raw water;
• said sealed container having raw water inlet means communicating with an inlet area above said filter material for supplying the raw water, and filtered water outlet means communicating with said lower chamber for exhausting filtered water from the container;
• a geofilter cloth being superimposed over all of the filter material in said sealed container, without any filter material being supported on top of the geofilter cloth, for supporting a biological "schmutzdecke" growth thereon;
• means for facilitating removal and replacement of the geofilter cloth when contaminated, without substantially disturbing and destroying a biological growth in the filter material, to facilitate regeneration thereof and continuously provide adequately treated drinking water;
• and
• means for slowly backfilling the container with water for removing entrapped air and completely filling the container up to a level slightly above that of the geofilter cloth after removal and replacement and when initiating use of the filtration system.

A filtration system for removing bacteria, viruses, algae, Giardia cysts, turbidity and other impurities in raw water supplied to a home or the like to provide suitable drinking water for human consumption, said system comprising:

• a sealed container divided into an upper and a lower chamber by support means, said support means supporting thereon a quantity of filter material sufficient for removing undesired bacteria, viruses, algae, Giardia cysts, turbidity and other impurities from the raw water;
• said sealed container having raw water inlet means communicating with an inlet area above said filter material for supplying the raw water, and filtered water outlet means communicating with said lower chamber for exhausting filtered water from the container;
• a geofilter cloth, supported by holding means, being superimposed over all of the filter material in said sealed container, without any filter material being supported on top of the geofilter cloth;
• a biological "schmutzdecke" growth being grown on said geofilter cloth, during use of the filtration system, to remove bacteria, viruses, algae, turbidity, Giardia cysts and other impurities and provide suitable drinking water;
• means for facilitating removal and replacement of the geofilter cloth when contaminated, without substantially disturbing and destroying a biological growth in the filter material, to facilitate regeneration thereof and continuously provide adequately treated drinking water;
• and
• means for slowly backfilling the container with filtered water to remove entrapped air and completely filling the container up to a level slightly above that of the geofilter cloth after removal and replacement and when initiating use of the filtration system without substantially disturbing the filter material during said slow backfilling.