Abstract: A method and apparatus is disclosed for resolving absorption spectra such as ultraviolet or visible spectra having individual peaks attributable to more than one component in a sample mixture. The invention exploits the observation that the peak wavelength varies according to the component concentrations, providing the basis for an initial estimate of these. A curve fitting exercise is performed for a range of possible concentrations encompassing the initial estimates so that the a theoretical spectrum having the closest match to that observed provides for a refined estimate of component concentrations.

Abstract: A process for the simultaneous determination of chlorine and chlorate in sodium hypochlorite. First and second streams of sodium hypochlorite are provided. The first stream is treated to generate iodine indicative of chlorine. The second stream is treated to generate iodine indicative of chlorine and chlorate. The iodine of the first stream is subjected to an amperometric measuring cell to generate a first current proportional to a chlorine concentration of the first stream. The iodine of the second stream is subjected to an amperometric measuring cell to generate a second current proportional to the chlorine and chlorate concentration in the second stream. The first current is subtracted from the second current to determine an amount of chlorate.

Abstract: Methods for reducing response time of membrane based electrochemical cells. A probe correction factor is calculated based on a percent rate of change in probe signal with time. A staged correction may be applied such that as signal change gets smaller, the effect of the compensation is reduced to prevent over shoot on the calculated residual. Control systems and techniques can regulate or control operations of a water treatment system.

Abstract: A process for the simultaneous determination of chlorine and chlorate in sodium hypochlorite. First and second streams of sodium hypochlorite are provided. The first stream is treated to generate iodine indicative of chlorine. The second stream is treated to generate iodine indicative of chlorine and chlorate. The iodine of the first stream is subjected to an amperometric measuring cell to generate a first current proportional to a chlorine concentration of the first stream. The iodine of the second stream is subjected to an amperometric measuring cell to generate a second current proportional to the chlorine and chlorate concentration in the second stream. The first current is subtracted from the second current to determine an amount of chlorate.

Abstract: A method and apparatus is disclosed for resolving absorption spectra such as ultraviolet or visible spectra having individual peaks attributable to more than one component in a sample mixture. The invention exploits the observation that the peak wavelength varies according to the component concentrations, providing the basis for an initial estimate of these. A curve fitting exercise is performed for a range of possible concentrations encompassing the initial estimates so that the a theoretical spectrum having the closest match to that observed provides for a refined estimate of component concentrations.

Abstract: A method for directly monitoring and controlling a continuous process stream for dechlorination residual is provided. A sample stream to which a dechlorination agent has been added to completely eliminate a residual disinfectant is continuously drawn off. An analyzing agent of iodine is provided by introducing an iodide solution, a chloramine-T solution, and an acetic acid buffer into the sample stream. The reagents quickly react to produce iodine that reacts with any residual disinfectant removal agent residual that may be present. Thereafter, the sample stream is continuously analyzed to determine the amount of unreacted iodine remaining in the process sample. Based on the amount of iodine added to the process sample and the amount of unreacted iodine remaining in the sample after reaction, the amount of dechlorination residual is continuously determined.