On-line application of ion chromatography in a thermal power plant

Complete monitoring of the “condensate-feedwater” cycle in power plants requires reliable automatic methods suitable for very low concentrations of various chemical species. A complete on-line ion-chromatography monitoring system is under development. It comprises an automatic on-line sampling system two Dionex Model QUIC (process instrument) ion chromatographs, an on-line calibration systems, and a data acquisition/processing system. The present model serves for the determination of sodium, chloride and sulfate ions. Detection limits are < 1 μg l^?1 (P = 95%) with liner ranges up to 10 μ l^?1 or about 200 μ l^?1 depending on settings. The importance of statistical evaluation of data is emphasized. The instrumentation was tested for sequential samples from crucial points of a 320-MW thermal power station with satisfactory results. Problems of reliability are discussed.