Patent ID: 7374683
Filing Date: 2008-05-20
Classification: C02F,Y02W

Abstract:
1. A biofilter for purifying a waste liquid, the biofilter comprising: a housing having an upper portion and a lower portion; a waste liquid inlet located in the upper portion of the housing; at least one layer of filtering material substantially comprised of organic material contained in the housing and disposed to receive the waste liquid therethrough, for supporting microorganisms capable of degradation of pollutants contained in the waste liquid under action of O a forced O a purified liquid outlet located in the housing below the gas inlet; and a gas collector located in the housing below at least a portion of said layer and above the gas inlet to retrieve at least some of the gas from inside the housing, thereby progressively reducing the remaining gas passing through said layer portion to control the proliferation of said microorganisms for limiting filter material clogging.