Methods for reducing the amount of contaminants in water

Details Methods for reducing the amount of contaminants in water Methods for reducing the amount of contaminants in water

2004-04-20

2004-11-23

Hruskoci, Peter A. (Department: 1724)

Liquid purification or separation

Processes

Treatment by living organism

C210S602000, C210S727000, C210S728000, C210S730000, C210S731000, C210S734000, C252S176000, C252S180000

Reexamination Certificate

active

06821427

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to methods for reducing the amount of contaminants in water, such as methods that utilize a chitosan salt disposed within a porous device that is at least partially immersed in running, contaminated, water.
BACKGROUND OF THE INVENTION
Storm water which runs off land cleared of vegetation, such as on construction sites and other developed sites, typically exhibits a high degree of contamination due to the presence of suspended sediment, metals, oil and other chemicals and particulate matter. Stringent water quality standards, enforced under the Clean Water Act, have created the need to purify contaminated stormwater. In addition, many cities and states have environmental regulations that require developers to utilize Best Management Practices to meet water quality standards. These regulations mandate that contaminated water must be collected and treated to reduce contamination before discharging into the environment, such as into streams and vegetated areas.
There is therefore a continuing need for devices and methods to reduce the amount of contaminants in water before it is discharged into the environment. Preferably the devices and methods utilize materials that are not toxic to the environment.
SUMMARY OF THE INVENTION
In accordance with the foregoing, in one aspect the present invention provides purification devices for reducing the amount of contaminants in water, each device includes a water-soluble flocculant disposed within a body defining a multiplicity of pores, wherein the pores have an average diameter in the range of from 1 &mgr;m to 2000 &mgr;m. In operation, the purification devices of the present invention are at least partially submerged in running, contaminated, water which dissolves at least a portion of the flocculant. The dissolved flocculant forms water-insoluble complexes with one or more contaminants in the water. The complexes can be removed from the treated water, such as by filtration. The purification devices of the present invention are therefore useful in any situation where reduction in the amount of contamination of water is desirable, such as in the treatment of turbid storm run-off water to reduce turbidity.
The present invention also provides methods for reducing the amount of contaminants in water. The methods of the invention each include the steps of: (a) at least partially immersing a purification device in running water, wherein (1) the purification device includes a water-soluble flocculant disposed within a body defining a multiplicity of pores, wherein the pores have an average diameter in the range of from 1 &mgr;m to 2000 &mgr;m; (2) the water comprises a contaminant; (3) the purification device is at least partially immersed in the running water under conditions whereby at least a portion of the flocculant is dissolved in the water and binds to at least some of the contaminant to form water-insoluble complexes; and (b) removing at least some of the water-insoluble complexes from the water. By way of example, at least some of the water-insoluble complexes can be removed from the treated water by dispersing treated water over a vegetated area; or dispersing treated water over a sand filter; or dispensing treated water into a settling tank wherein the water-insoluble complexes sediment.
The methods of the invention are useful in any situation where it is desired to reduce the amount of contaminants in water, such as, for example, reducing the amount of contaminants in water running off excavation and construction sites, and reducing the amount of contaminants in storm run-off water. The devices of the invention are useful, for example, in the methods of the invention.


REFERENCES:
patent: 2072976 (1937-03-01), Andrus
patent: 3533940 (1970-10-01), Peniston et al.
patent: 3839202 (1974-10-01), Roy
patent: 4382864 (1983-05-01), Hashimoto et al.
patent: 4820424 (1989-04-01), Field et al.
patent: 4822579 (1989-04-01), Wagner
patent: 4975542 (1990-12-01), Hirayama et al.
patent: 5053113 (1991-10-01), Krepets et al.
patent: 5336415 (1994-08-01), Deans
patent: 5708152 (1998-01-01), Lohmann et al.
patent: 5932107 (1999-08-01), Domard et al.
patent: 6130321 (2000-10-01), Johnson et al.
patent: 6203711 (2001-03-01), Moffett
patent: 6403032 (2002-06-01), Abercrombie et al.
patent: 6749748 (2004-06-01), Macpherson et al.
patent: 62-62827 (1987-03-01), None
patent: 8-269104 (1996-10-01), None
patent: 9-143205 (1997-06-01), None
patent: WO 00/50090 (2000-08-01), None
patent: WO 97/42975 (1997-11-01), None
Allan, G.G. and M. Peyron, “Molecular weight manipulation of chitosan I: Kinetics of depolymerization by nitrous acid,”Carbohydrate Research, 277:257-272, 1995.
Bégin, A., and M-R. Van Calsteren, “Antimicrobial Films Produced From Chitosan,”International Journal of Biological Macromolecules 26: 63-67, 1999.
Demarger-André, S., and A. Domard, “Chitosan Behaviours in a Dispersion of Undecylenic Acid,”Carbohydrate Polymers 22:117-126, 1993.
Demarger-André, S., and A. Domard, “Chitosan Behaviours in a Dispersion of Undecylenic Acid. Morphological Aspects,”Carbohydrate Polymers 27:101-107, 1995.
Domard, A., and N. Cartier, “Glucosamine Oligomers: 1, Preparation and Characterization,”International Journal of Biological Macromolecules 11:297-302, 1989.
Focher, B., et al., “Chitosans FromEuphausia Superba.2: Characterization of Solid State Structure,”Carbohydrate Polymers 18:43-49, 1992.
Kikkawa, Y., et al., “A Convenient Preparation Method of Chito-Oligosaccharides by Acid Hydrolysis,”J. Fac. Agric. Tottori Univ. 26:9-17, 1990.
Kumar, M.N.V.R., “A Review of Chitin and Chitosan Applications,”Reactive&Functional Polymers 46:1-27, 2000.
Li, J., et al., Effect of Degree of Daecetylation of Chitin on the Properties of Chitin Crystallites, John Wiley & Sons, Inc. ccc 0021-8995/97/020373-08, 1997, pp. 373-380.
Muzzarelli, R.A.A., “Chitosan-Based Dietary Foods,”Carbohydrate Polymers 29:309-316, 1996.
Product Literature, describing Sea-Klear® Tablets and Sea-Klear® Liquid, which were on sale at least as early as May 1, 1998 (3 pp).
Product Literature, Wilke Resources, Inc. Product literature disclosing chitosan useful in kits of the invention, Jul. 1998.
Qu, X., et al., “pH-Sensitive Hydrogels Based on Chitosan and D,L-Lactic Acid,”Rapra Abstracts,Oxford, Pergamon Press Ltd. 36(4):117, Apr. 1999.
Rogozhin, S.V., et al., “The Partial Acidic Hydrolysis of Chitosan,”Polymer Science U.S.S.R. 30(3):607-614, 1988.
Signini, R. and S.P. Campana Filho, “On the Preparation and Characterization of Chitosan Hydrochloride,”Polymer Bulletin 42:159-166, 1999.
T. Yui et al., “Molecular and Crystal Structure of the Anhydrous Form of Chitosan,”Macromolecules,27:7601-7605, 1994.
Vincendon, M., “Regenerated Chitin From Phosphoric Acid Solutions,”Carbohydrate Polymers 32:233-237, 1997.

Affiliated with

Also associated with

Rating

Methods for reducing the amount of contaminants in water does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Methods for reducing the amount of contaminants in water, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods for reducing the amount of contaminants in water will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3356325