Patent ID: 6540910
Filing Date: 2003-04-01
Classification: B01D,C02F

Abstract:
In a filtration system wherein wastewater from a septic tank is directed into perforated primary distribution pipes on an upper surface of a filtration bed of granular material, through which bed the wastewater from the primary pipes descends to perforated collection pipes at a low level in the filtration bed, and wastewater emerging from the collection pipes is then directed through flow divider means from which some wastewater is discharged and remaining wastewater is recirculated back through said filtration bed, the improvement comprisinga) perforated secondary distribution pipes into which said remaining wastewater is recirculated at a level in the filtration bed below the primary pipes and above the collection pipes, and b) respective coextensive perforated hood elements arched over the respective secondary pipes spacing them from the granular material above and to each side.