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US 5,470,480 AGranted
Process for treating waste water effluent
AssigneeEka Nobel AB
InventorsJohn M. Gray, David C. Lovetro
Life of this patent
Estimating the term…
Abstract
Waste water effluent streams are treated with hydrogen peroxide and ultraviolet radiation. Hydroxyl ions formed by action of UV on H.sub.2 O.sub.2 reduces BOD, COD, AOX and color in effluent. In the case of pulp mill effluent, some or all of the effluent can then be recycled to the pulp mill.
Claims22
A method for decreasing the contaminant burden in pulp and paper mill effluent comprising the steps of:
- (a) providing a waste water effluent containing a first level of organic contaminants;
- (b) determining the amount of organic contaminants in said effluent by measuring at least one of chemical oxygen demand, total organic carbon, color, absorbable organic halogens, or biological oxygen demand;
- (c) adding hydrogen peroxide to the effluent in an amount sufficient to reduce the amount of organic contaminants to a second level lower than said first level;
- (d) adding peroxidase enzyme to the effluent in a catalytically effective amount for increasing the activity of said hydrogen peroxide;
- (e) irradiating the effluent from step (d) with at least about 780 watt minutes of ultraviolet radiation to promote the formation of hydroxyl radicals from the added hydrogen peroxide;
- (f) oxidizing a sufficient portion of the organic contaminants with the hydroxyl radicals formed in steps (d) and (e) to reduce the level of said contaminants to said second level.
3 more elements
Dependencies are inferred from the claim text.