Controlling chlorination of wastewater and chloramination of drinking water
AssigneeHach Company
InventorsDanial L. Harp, Patrick Wiese, Stanley Franklin
Life of this patent
Estimating the term…
Abstract
A method is described for precisely controlling chlorination of wastewater and chloramination of drinking water. The method involves analyzing the water for the presence of residual monochloramine without interference of dichloramine, organic amines, organic chloramines or nitrites. A color-forming reagent is added to a sample of the water which will develop a colored compound upon reaction with monochloramine, after which the sample may be colorimetrically analyzed to determine the amount of monochloramine present. The method is very accurate and avoids the problems associated with conventional tests used for chlorination control.
Claims7
In a method for disinfection of water by contacting the water with chlorine in the presence of ammonia wherein chloramines are formed, the improvement which comprises analyzing said water after addition of said chlorine to determine the concentration of monochloramine in said water without interference of dichloramine or organic chloramines, and comprising the additional steps of (a) adding an additional amount of chlorine to said water, and (b) analyzing said water after said additional amount of chlorine has been added to determine the concentration of monochloramine without interference of of dichloramine or organic chloramines;
- wherein said steps (a) and (b) are repeated until the concentration of monochloramine in said water is sufficient to provide adequate disinfection of said water.
A method for disinfection of water in the presence of ammonia by forming monochloramine in said water, and avoiding production of dichloramine and organic chloramines, the method comprising the steps of:
- (a) contacting said water with chlorine, wherein the mass ratio of chlorine to ammonia nitrogen is less than about 5:1, whereby monochloramine is formed;
- (b) analyzing said water to determine the concentration of said monochloramine in said water without interference of dichloramine or organic chloramines;
- and
- (c) repeating steps (a) and (b) until the concentration of monochloramine in said water is sufficient to disinfect said water.
Dependencies are inferred from the claim text.