Methods for treating wastewater using an organic coagulant
AssigneeDeLaval Holding AB
InventorReed Semenza
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Abstract
A wastewater treatment system is disclosed which uses algae to generate oxygen for primary digestion of municipal wastewater. A coagulant composition containing a cationic starch and an aluminum salt is used to remove algae and other solids from the wastewater stream. The unique combination of the starch coagulant and algae species produced water of exceptionally low turbidity.
Claims26
A method for removing solids from a liquid suspension, comprising the step of adding to said liquid suspension an effective amount of a composition comprising a cationic starch and an aluminum salt.
A method for removing algae from a wastewater treatment system comprising the steps of:
- (a) providing a supply of wastewater containing at least one species of algae;
- and
- (b) adding to said algae-containing wastewater a quantity of a composition comprising a cationic starch and an aluminum salt having the formula AlnCl(3n-m)(OH)m, wherein n is an integer ranging from 1 to 20, m is an integer ranging from 1-20, said composition causing at least a portion of said algae in said wastewater to coagulate and settle out of said wastewater.
A wastewater treatment system comprising a reservoir containing a volume of wastewater, said wastewater having an amount of solids suspended therein, and wherein at least a portion of said suspended solids comprise one or more species of algae, said wastewater contained within said reservoir comprising a quantity of a coagulant composition, said coagulant composition comprising a cationic starch and an aluminum salt, said reservoir configured to hold said wastewater for a sufficient period of time to permit coagulation and settling of at least a portion of the algae suspended in said wastewater.
Dependencies are inferred from the claim text.