Automatic on-line chemistry monitoring system having improved

Abstract

A system for automatically sampling, monitoring and analyzing power plant steam cycle water supplied from various points in a power plant steam cycle system as a plurality of influent fluid sample streams. Plural continuous monitor modules each include continuous on-line monitors and provide continuous on-line monitoring of a corresponding influent fluid sample stream, and an ion chromatograph unit provides semi-continuous monitoring of a selected one of the influent fluid sample streams. Each continuous monitor module also includes an improved calibration unit including a conditioning unit which creates a pressure differential in the influent fluid sample stream and utilizes the pressure differential to inject a mixed standard solution into the influent fluid sample stream, thereby providing a conditioned influent fluid sample stream having predetermined chemical characteristics; the continuous on-line monitors are calibrated with respect to the predetermined chemical characteristics of the corresponding conditioned influent fluid sample stream and the ion chromatograph unit is calibrated with respect to the predetermined chemical characteristics of the selected conditioned influent fluid sample stream supplied thereto. A control unit receives signals representative of the monitored chemical characteristics from the continuous on-line monitors and the ion chromatograph unit and uses these signals in a feedback loop to control the monitoring system, to automatically calibrate the continuous on-line monitors and the ion chromatograph unit in accordance with the predetermined chemical characteristics of the conditioned influent fluid sample streams, and to detect, analyze and correct steam cycle water chemistry changes before corrosion or other problems related to water chemistry imbalances.