Method for clarifying industrial wastewater
OwnerRobert Davis, Stuart Davisinventors
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Abstract
Methods are described for removing contaminates from aqueous industrial wastewater process streams, specifically industrial laundries to yield a less contaminated aqueous effluent for discharge to a sewer and reduce the sludge generated therefrom. A premixed medium/high molecular weight and medium/high charged cationic coagulant solution polymer and an inorganic aluminum species is added to the wastewater, and after at least a two second delay, a high molecular weight highly charged anionic flocculent is injected into the wastewater which reduces sludge generation, while maintaining or exceeding effluent quality. Also, no coagulant, flocculent or sludge aids are needed to attain the results and the sludge can be dewatered in a plate and frame press.
Claims21
A method for clarifying wastewater containing contaminants, comprising:
- adding a cationic blend consisting essentially of poly[2-hydroxypropyl-N,N-dimethylammonium chloride] and aluminum chlorohydrate (ACH) to the wastewater in an effective amount to break emulsified bonds of the contaminants in the wastewater and produce cationic-charged coagulated particles having sufficient mass and cationic charge to react with an anionic flocculent to be added thereafter;
- and
- subsequent to a sufficient delay to permit the cationic blend to coagulate the cationic-charged coagulated particles in the wastewater, adding the anionic flocculent to the wastewater in an effective amount to react with the cationic-charged coagulated particles to form flocculated waste particles of effective size to form sludge in disposable clarified water.
A method for clarifying wastewater containing contaminants, comprising:
- (a) adding a cationic blend consisting essentially of poly[2-hydroxypropyl-N,N-dimethylammonium chloride] and aluminum chlorohydrate (ACH) in an amount of between about 25 ppm and about 1500 ppm to the wastewater to break emulsified bonds of the contaminants in the wastewater and produce cationic-charged coagulated particles having sufficient mass and cationic charge to react with an aqueous anionic polymer flocculent to be added thereafter;
- (b) delaying addition of the aqueous anionic polymer flocculent by at least a sufficient time to permit the cationic blend to substantially complete the coagulation of the cationic-charged coagulated particles in the wastewater in said adding (a);
- and
- (c) adding the aqueous anionic polymer flocculent in an amount between about 5 ppm and about 50 ppm and of sufficient molecular weight and charge density to the wastewater so as to react with the cationic-charged coagulated particles to form flocculated waste particles of effective size to form sludge in disposable clarified water.
A method for clarifying wastewater containing contaminants, comprising:
- (a) adding a cationic blend about 5 to about 50 weight percent consisting essentially of poly[2-hydroxypropyl-N,N-dimethylammonium chloride] and about 5 to about 40 weight percent aluminum chlorohydrate (ACH) to the wastewater in an amount of between about 25 ppm and about 1500 ppm to break emulsified bonds of the contaminants in the wastewater and produce cationic-charged coagulated particles having sufficient mass and cationic charge to react with an aqueous anionic polymer flocculent to be added thereafter;
- (b) delaying addition of the aqueous anionic polymer flocculent by at least a sufficient time to permit the cationic blend to substantially complete the coagulation of the cationic-charged coagulated particles in the wastewater in said adding (a);
- and
- (c) adding the aqueous anionic polymer flocculent in an amount between about 5 ppm and about 50 ppm and of sufficient molecular weight and charge density to the wastewater so as to react with the cationic-charged coagulated particles to form flocculated waste particles of effective size to form sludge in disposable clarified water.
Dependencies are inferred from the claim text.