Method and apparatus for mechanically and chemically treating liquids

An apparatus for mechanical or mechanical-chemical treatment of liquids containing pollutants by destabilization, flocculation, sedimentation and thickening of the pollutants contained therein, leaving essentially solid-free liquid, comprising:

• a separate destabilization compartment, means for passing the liquids from the separate destabilization compartment to a separate flocculation compartment located downstream from the destabilization compartment and including means to aid in forming settleable flocculated solids, means for passing the liquid from the flocculation compartment to a treatment tank located downstream from the separate flocculation compartment, said treatment tank having an upper compartment and a lower compartment, the lower compartment being located beneath the upper compartment and in open communication therewith, said upper compartment being a sedimentation compartment including a plurality of inclined channels, means for introducing the liquid into said channels and flowing the liquid therethrough, means for separating out the settleable flocculated solids from the liquid as the liquid flows through the channels, means for removing the solid-free liquid at a location above the bottom ends of the channels for substantially minimizing liquid flow below the channels, and means for discharging the said solids from the lower ends of the channels such that they fall under gravity into the lower compartment under said minimized liquid flow conditions existing thereat, and the lower compartment being a thickening compartment in which thickening of said solids takes place, the thickening compartment including a mechanical means for engaging the said solids falling into the thickening compartment to further thicken the same, wherein the bottom ends of the channels are arranged and distributed above said thickening compartment in such a manner that the lower ends of the channels run directly into said lower compartment over 50 to 100% of the area of the top of said lower compartment, and removing means separate from the thickening means and located below the thickening means.

A method for mechanical or mechanical-chemical treatment of liquids containing pollutants therein by means of destabilization, flocculation, sedimentation and thickening of the sedimented solids, comprising the steps of:

• destabilizing and aiding flocculation of the pollutants to form settleable flocculated solids suspended in the liquid,
• dividing the liquid to be treated in a first zone which is a sedimentation zone into a plurality of flow paths in the form of inclined channels and flowing said liquid through said channels and settling out the settleable flocculated solids from the liquid as the liquid flows through said channels,
• discharging the said solids from the bottom ends of said channels so that they can fall in a uniformly distributed manner downwardly into a second zone which is a thickening zone,
• the introducing of said liquid to be treated into said channels and the removal of the solid-free liquid from said channels being done at a location above the lower ends of said channels to keep the said thickening zone substantially free of liquid flow,
• thickening the solids within the thickening zone with a mechanical means located therein and positioned to contact the solids as they fall therethrough,
• and removing the thickened solids out of the said thickening zone with a removing means separate from the thickening means and located below the thickening means.

An apparatus for mechanical or mechanical-chemical treatment of liquids containing pollutants therein by destabilization, flocculation, sedimentation and thickening of the pollutants contained therein, leaving separated essentially solid-free liquid, comprising:

• means defining a destabilization zone in which the liquid is destabilized, means for aiding in the formation of settleable flocculated solids and means for passing the liquid having the settleable flocculated solids to a sedimentation zone,
• a treatment tank having an upper compartment and a lower compartment, the lower compartment being located beneath the upper compartment and in open communication therewith,
• the upper compartment forming the said sedimentation zone and having a plurality of inclined channels, and the lower compartment being a thickening zone,
• means for introducing the liquid to be treated into said channels and flowing the liquid therethrough and settling out the settleable flocculated solids from the liquid as the liquid to be treated flows therethrough, and means for removing the solid-free liquid from the channels,
• both of said means for introducing liquid to be treated into the channels and said means for removing the solid-free liquid from the channels being located above the lower ends of the said channels to keep the thickening zone substantially free of liquid flow,
• means for discharging the said solids from the bottom ends of the channels such that they fall under gravity into the thickening zone under said minimized liquid flow conditions existing therein,
• said thickening zone including a mechanical means for engaging the said solids as they fall into the thickening zone,
• the bottom ends of the channels being arranged and distributed above the thickening zone such that the lower ends of the channels are located over a major part of the area of the top of the thickening zone,
• and removing means separate from the thickening means and located below the thickening means for removing thickened settled solids which have settled in the thickening zone.