Patent ID: 6451613
Filing Date: 2002-09-17
Classification: G01N,Y10T

Abstract:
An instrument for measuring the total organic carbon content (TOC) of a stream of water, comprising:means for splitting said stream of water into two portions, a static-sample analytical module connected to said means for splitting, said module comprising a cell for containing a sample of said stream of water, means for controlling flow of water through said cell and for stopping flow to define such a sample, said cell having at least a window therein transparent to ultraviolet radiation (UV) a source of UV juxtaposed to said window to irradiate said sample, electrodes within said cell across which the conductivity of said sample can be measured, and means for determining the TOC of said sample responsive to measurement of the conductivity thereof; a continuous-flow analytical module connected to said means for splitting, said module comprising a first cell comprising electrodes across which the conductivity of said stream of water can be measured, a vessel for containing said stream of water that at least includes a window that is transparent to UV, a source of UV juxtaposed to said window to irradiate said stream, a second cell comprising electrodes across which the conductivity of said stream of water can be measured after UV irradiation, and means for determining the difference in the conductivity of said stream of water after irradiation with respect to its conductivity before irradiation; means for estimating the TOC of said stream responsive to said difference in the conductivity of said stream; means for monitoring the difference in the conductivity of said stream over time, and for identifying a departure from the monitored value; and means for calibrating the value of the TOC of said stream estimated responsive to said difference in the conductivity of said stream by comparison to the value of the TOC thereof determined in said static-sample module.