Patent ID: 6790664
Filing Date: 2004-09-14
Classification: G01N,Y10T

Abstract:
A method of determining the amount of soluble hardness in the water of an industrial water system comprising the steps of:1) providing an industrial water system; 2) providing a Compound, wherein said Compound is selected from the group of chemicals that develop a separate detectable fluorescent signal in the presence of soluble hardness; 3) extracting a sample of water from the industrial water system and determining whether the sample of water is at or below the maximum temperature of operability of said Compound, and if the sample of water is above the maximum temperature of operability of said Compound, then cooling said sample of water until the temperature of the sample of water is at or below the maximum temperature of operability of said Compound; 4) measuring the pH of the sample of water and determining whether the pH is between about 7.5 and about 13.5 and if the pH is not between about 7.5 and about 13.5, adjusting the pH of the sample of water such that the pH is between about 7.5 and about 13.5; 5) adding to said sample of water from about 1 ppb to about 3,000 ppm of said Compound; 6) providing a fluorometer; 7) using said fluorometer to measure the separate detectable fluorescent signal of said Compound in said sample of water; 8) using said separate detectable fluorescent signal to determine the amount of soluble hardness in said sample of water.