摘要 |
An analyzer for continuously and accurately measuring the hypochlorous acid content of chlorinated water containing free available chlorine having a hypochlorous acid component (HOCl) which is a highly reactive disinfectant and a less reactive hypochlorite ion component (OCl-). To make this determination, a sample of the chlorinated water is sensed by three probes-one yielding an analog signal representing the free available chlorine content (FAC) of the sample; the second, an analog signal representing the pH of the sample; the third, an analog signal representing the sample temperature (T). These signals are digitized and applied as input data to a digital computer wherein the percentage of HOCl in the sample at a reference temperature is established on the basis of the pH data by consulting a memory storing the relationship between the percentages of HOCl and OCl- in a range of pH values. The percentage of HOCl so established is then corrected on the basis of the T data by consulting a memory storing the relationship between temperature and the equilibrium constant of HOCl. Finally, the temperature-corrected percentage of HOCl is multiplied by the FAC data to determine the HOCl content of the sample.
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