Patent ID: 6755972
Filing Date: 2004-06-29
Classification: C02F,Y02W

Abstract:
An installation for the biological purification of urban waste water including:waste water entrance duct means; a first sludge settlement section for receiving the urban waste water and braking down impurities in suspension and consumption of said impurities by living microscopic and macroscopic organisms; a pump station adapted to perform firstly a recirculation of a portion of the waste water contained within said first sludge settlement section, said pump station being positioned close to an outlet end of said first sludge settlement section for recirculating the portion of the waste water back to a point upstream of said first sludge settlement section where said portion of waste water is mixed with waste water being conveyed to said first sludge settlement section, said pump station also transferring sludge formed within said first sludge settlement section to a compost production area; a plurality of earthen structures each filled with a layer of inert material, said earthen structures being connected in series so that water passing therethrough passes to an immediately adjacent one of said earthen structures downstream thereof, wherein the water flowing through said plurality of earthen structures is purified due to removal therefrom of nutrient contents by action of roots of vegetation planted within each of said earthen structures and which vegetation grows within voids in said layers of inert material, and purified water exit duct means for receiving purified water from said plurality of earthen structures and, wherein a desired degree of purity of the urban waster water, for a given quality of incoming urban waster water is used to determine a total area of said plurality of earthen structures.