Methods and systems for reducing biofouling of microfiltration membranes
AssigneeWater Solutions, Inc.
InventorsStephen D. Allen, Edward Lewis
Life of this patent
Estimating the term…
Abstract
Systems and methods for reducing biofouling of microfiltration membranes that are biofouled with biological substances are disclosed. The methods include providing impound water containing biomolecule-based exopolymeric substances, reacting with calcium oxide or calcium hydroxide, encapsulating the exopolymeric substance into filterable non-tacky particles by reacting with an inorganic coagulant and a low molecular weight polymer, and microfiltering to remove the filterable non-tacky particles encapsulating the exopolymeric substances. The filterable non-tacky particles encapsulate the exopolymeric substances and prevent the exopolymeric substances from biofouling the microfiltration membranes.
Claims14
A method for reducing biofouling of microfiltration membranes by a biomolecule-based exopolymeric substance, the method comprising:
- providing impound water comprising a biomolecule-based exopolymeric substance;
- reacting the impound water with calcium oxide or calcium hydroxide to generate a calcium-treated biomolecule-based exopolymeric substance mixture;
- encapsulating the reacted biomolecule-based exopolymeric substance into filterable, non-tacky particles by reacting the calcium-treated biomolecule-based exopolymeric substance mixture with an aluminum-based inorganic coagulant and a cationic polymer having a molecular weight in the range from about 200,000 to about 800,000 Daltons (Da) having a molecular weight in the range from 200,000 to 800,000 Da;
- removing a first portion of the encapsulated biomolecule-based exopolymeric substance as bulk solid;
- and
- removing a second portion of the encapsulated biomolecule-based exopolymeric substance by low pressure microfiltration through a microfiltration membrane comprising a pore size of between about 0.7 to 12 microns,
- wherein encapsulating the biomolecule-based exopolymeric substance into filterable, non-tacky particles reduces biofouling of the microfiltration membrane.
A method for removing polysaccharide-based exopolymeric substance from an aqueous mixture, the method comprising:
- providing an aqueous mixture, the aqueous mixture containing exopolymeric substance and one or more of dissolved solids, suspended solids or heavy metals;
- reacting the aqueous mixture with calcium oxide or calcium hydroxide to generate a calcium-treated mixture;
- encapsulating the reacted polysaccharide-based exopolymeric substance into filterable, non-tacky particles by reacting the calcium-treated mixture with aluminum chlorohydrate and epi-dma (poly(epichlorhydrin-dimethylamine);
- mechanically removing a first portion of the encapsulated polysaccharide-based exopolymeric substance as bulk solid;
- and
- microfiltering to remove a second portion of the encapsulated polysaccharide-based exopolymeric substance.
Dependencies are inferred from the claim text.