Tagged epichlorohydrin-dimethylamine copolymers for use in wastewater treatment

Method for controlling a concentration of a water soluble polymeric treating agent added to wastewater comprising the steps of:

• a. adding to wastewater being confined in a once through wastewater treatment system a predetermined dose of a water soluble polymeric treating agent bearing a fluorescent moiety tag covalently bonded thereto, said wastewater containing liquid and solid portions;
• b. removing a sample of said wastewater containing said polymeric treating agent;
• c. separating the solid and liquid portions of said sample;
• d. measuring emissivity of the liquid portion of said sample as a measure of the concentration of the polymeric treating agent in the wastewater sample;
• e. continuously repeating steps (a) through (d) to monitor the emissivity as a function of the added amount of the polymeric treating agent;
• and
• f. adjusting the concentration of the polymeric treating agent in the wastewater according to the changes in slope of the emissivity versus the added dose of the polymeric treating agent.