Sensor for monitoring for the presence and measurement of aqueous aldehyde biocides

An analytical system for the real-time detection, measurement and recording of the concentration of any aqueous aldehyde-based biocidal compounds present in an aqueous solution flowing in a conduit at a sampling point, the system comprising:

• a sample delivery valve having an inlet in fluid communication with the conduit (6) at the sampling point and an outlet for delivering a sample of the aqueous solution to an aqueous sample storage vessel;
• a mixing vessel;
• an aqueous sample metering pump having an inlet in fluid communication with the aqueous sample storage vessel and an outlet in fluid communication with the mixing vessel for delivering a predetermined volume of the aqueous solution to the mixing vessel;
• a reagent metering pump having an inlet in fluid communication with a reagent storage vessel containing a reagent and an outlet in fluid communication with the mixing vessel for delivering a predetermined volume of the reagent to the mixing vessel, the reagent comprising a solution of dimedone and a buffering agent in an amount necessary to maintain a pH in the range of from 4.0 to 5.0;
• a heating vessel in fluid communication with the mixing vessel for receiving and heating the reaction mixture and any reaction product to a predetermined temperature;
• an optical detection cell in fluid communication with the heating vessel for receiving and circulating the heated reaction mixture and any reaction product, the optical detection cell constructed as a two-part assembly comprising a flow cell and a light sensor portion;
• and
• a microprocessor connected to the light sensor portion for receiving and storing in memory an electrical signal corresponding to any light emitted by a reaction product and configured to produce a graphic and/or data display corresponding to the intensity of the light emission.