Advertisement

Thermal Engineering

, Volume 65, Issue 11, pp 854–858 | Cite as

The Measurement of pH in Superpure Condensate and Feedwater of Power Units

  • A. B. Larin
  • B. M. Larin
  • A. Ya. Sorokina
  • S. V. Kiet
Water Treatment and Water Chemistry

Abstract

The change-over to the European standards for the quality of water coolant in power units of thermal and nuclear power stations makes the requirements for the feedwater quality stricter and brings about problems in the measurement of pH. The conventional calibration of a pH-meter against buffer solutions does not yield the measurement accuracy during measurements in infinitely diluted water solutions with electrical conductivity below 0.3 μS/cm. Reliability and validity of pH measurements can be improved by using the readings of automatic conductivity meters and calibration of analyzer in a superpure medium. The first method is implemented in foreign-made instruments, such as FAM Deltacon pH and AMI Deltacon Power. The second method has not yet been developed and is waiting for its implementation in practice. The investigation of the possibility for implementation of these methods using domestic equipment was carried out in the laboratory at the ion-exchange membrane test facility with metering ammonia or carbonic acid solution into deeply demineralized water and was verified under actual operating conditions at the Petrozavodsk Cogeneration Power Station (TETs) and the Kostroma District Power Station (GRES). This investigation resulted in the design of a prototype of a Lider-APK industrial analyzer intended for measurement of pH and concentration of impurities (such as ammonia, sodium, or chlorides) in condensate type waters in the range of pH = 6.0–10.0, and the development of a calibration procedure of industrial bench test pH-meters using ammonia or carbonic acid solutions. The Lider-APK analyzer outperforms its import equivalents and can be used in the automatic chemical monitoring at thermal power stations (TPS). A procedure for calibration of pH-meters in ultradiluted solutions has been first developed and should be verified at industrial facilities. The results of investigation suggest that both methods can improve the reliability of pH measurements in a superpure water coolant using automatic analyzers.

Keywords

electrical conductivity pH ammonia concentration power unit feedwater calibration of automatic analyzers 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    STO 70238424.27.100.013-2009. Water Treatment Units and Water Chemistry of Thermal Power Plants. Requirements (InVEL, Moscow, 2009).Google Scholar
  2. 2.
    VGB-R 450 Le. Guidelines for Feed Water, Boiler Water and Steam Quality for Power Plants /Industrial Plants, 2nd ed. (VGB PowerTech, 2004); VGB-S-010-T-00. Guidelines for Feed Water, Boiler Water and Steam Quality for Power Plants /Industrial Plants, 3rd ed. (VGB PowerTech, 2011).Google Scholar
  3. 3.
    STO 1.1.1.07.003.0818-2016. Water Chemistries of the Secondary Circuit of a Nuclear Power Plant with VVER-1000. Quality Standards for the Working Environment and Means of Their Provision (Rosenergoatom, Moscow, 2016).Google Scholar
  4. 4.
    Operational Circular No. T-1/77. On the Order of pH Determination in the Range from 8.0 to 10.0 of Feed Water of Direct-Flow Supercritical Pressure Boilers by Laboratory pH Meters (SPO ORGRES, Moscow, 1977) [in Russian].Google Scholar
  5. 5.
    RD 34.37.308-90. Procedural Guidelines for Determining the pH of Feed Water of Direct-Flow Supercritical Pressure Boilers in the Range From 8.0 to 10.0 (SPO ORGRES, Moscow, 1991).Google Scholar
  6. 6.
    B. M. Larin, A. B. Larin, and A. V. Kolegov, Measuring the Electrical Conductivity and pH in Water Regime Monitoring Systems of TPPs (IGEU, Ivanovo, 2014) [in Russian].Google Scholar
  7. 7.
    S. V. Kiet, V. N. Voronov, and E. N. Bushuev, “Using an APK-051 analyzer in a chemical engineering monitoring system,” Therm. Eng. 56, 617–620 (2009).CrossRefGoogle Scholar
  8. 8.
    B. M. Larin, A. B. Larin, A. Ya. Sorokina, and S. V. Kiet, Patent RF No. 2573453. Byull. Izobret., No. 2 (2016).Google Scholar
  9. 9.
    A. B. Larin and A. Ya. Sorokina, “Procedure for calculating the pH and concentrations of ionic impurities of feed water at thermal power plants from measurements of the electrical conductivity,” Vestn. Ivan. Gos. Energ. Univ., No. 5, 10–15 (2016).Google Scholar
  10. 10.
    E. N. Bushuev, E. V. Kozyulina, B. M. Larin, and M. Yu. Oparin, Patent RF No. 2244294, Byull. Izobret., No. 1 (2005).Google Scholar
  11. 11.
    A. K. Rodionov, Patent RF No. 2324927, Byull. Izobret., No. 14 (2008).Google Scholar
  12. 12.
    V. G. Kiet, S. V. Kiet, B. M. Larin, and A. B. Larin, Patent RF No. 177955, Byull. Izobret., No. 8 (2018).Google Scholar

Copyright information

© Pleiades Publishing, Inc. 2018

Authors and Affiliations

  • A. B. Larin
    • 1
  • B. M. Larin
    • 1
  • A. Ya. Sorokina
    • 1
  • S. V. Kiet
    • 2
  1. 1.Ivanovo State Power Engineering University (IGEU)IvanovoRussia
  2. 2.OOO Scientific and Production Enterprise (NPP) TecknopriborMoscowRussia

Personalised recommendations