Microporous filter media with intrinsic safety feature
AssigneeKoslow Technologies Corporation
InventorEvan E. Koslow
Life of this patent
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Abstract
The present invention is directed to a microporous filter medium treated with a microbiological interception enhancing agent comprising a cationic chemical having a medium to high charge density and a molecular weight greater than about 5000 Daltons, adsorbed on at least a portion of the microporous structure, and a biologically active metal in direct proximity to the cationic chemical and also on at least a portion of the microporous structure, wherein the flow of fluid through the filter medium decreases in response to an amount of polyanionic acids present in an influent. Robust microbiological interception is still maintained due to the extended empty bed contact time as a result of the diminished flow rate.
Claims18
A filter medium comprising:
- a microporous structure having a mean flow pore size of less than about 2 microns;
- and
- a microbiological interception enhancing agent comprising a cationic chemical having a medium to high charge density and a molecular weight greater than about 5000 Daltons, adsorbed on at least a portion of said microporous structure, wherein the cationic chemical forms a by-product in the presence of excess polyanionic acids in an influent thereby reducing flow through said filter medium to prevent passage of microbiological contaminants.
A filter medium comprising:
- a microporous structure having a mean flow pore size of less than about 2 microns;
- and
- a microbiological interception enhancing agent comprising a cationic chemical having a medium to high charge density and a molecular weight greater than about 5000 Daltons, adsorbed on at least a portion of said microporous structure, and a biologically active metal in direct proximity to the cationic chemical wherein the biologically active metal is caused to precipitate with at least a portion of a counter ion associated with the cationic chemical, and wherein the cationic chemical forms a by-product in the presence of excess polyanionic acids in an influent thereby reducing flow through said filter medium to prevent passage of microbiological contaminants.
A method of filtering a fluid containing microbiological contaminants and polyanionic acids, comprising the steps of:
- providing a filter medium having an intrinsic safety feature comprising a microporous structure having a mean flow pore size of less than about 2 microns, wherein the microporous structure is treated with a microbiological interception enhancing agent comprising a cationic chemical having a medium to high charge density and a molecular weight greater than about 5000 Daltons, adsorbed on at least a portion of the microporous structure, and a biologically active metal in direct proximity to the cationic chemical also on at least a portion of the microporous structure;
- passing the fluid containing microbiological contaminants and polyanionic acids through the filter medium;
- and
- obtaining greater than about 4 log reduction of microbiological contaminants in an effluent,
- wherein a flow of fluid through the filter medium is reduced as a result of the polyanionic acids reacting with the cationic chemical, thereby preventing passage of the microbiological contaminants while retaining enhanced interception of the microbiological contaminants.
A gravity-flow filtration system for treating, storing, and dispensing fluids comprising:
- a first reservoir for holding a fluid to be filtered;
- a filter medium in fluid communication with said first reservoir, said filter medium comprising a microporous structure with a mean flow pore size of less than about 1 micron, said filter medium treated to provide at least about 4 log reduction of microbiological contaminants smaller than the mean flow pore size of said filter medium, wherein the flow of fluid through said filter medium decreases in response to an amount of polyanionic acids present in the fluid;
- and
- a second reservoir in fluid communication with said filter medium for collecting a filtered fluid.
A pressurized filtration system for treating, and dispensing fluids comprising:
- a reservoir for collecting a filtered fluid;
- and
- a filter medium in fluid communication with said reservoir, said filter medium comprising a microporous structure with a mean flow pore size of less than about 2 microns, said filter medium treated to provide at least about 4 log reduction of microbiological contaminants smaller than the mean flow pore size of said filter medium, wherein the flow of fluid through said filter medium decreases in response to an amount of polyanionic acids present in the fluid.
Dependencies are inferred from the claim text.