Methodology for studying the quality of steam condensate and cooling water of a steam turbine condenser
Authors: Larin A.B. , Kozlovsky V.V. , Savinov M.P. 
Published: September 2020

Monitoring the suction of cooling water into steam with measurements of , H and pH of condensate is simultaneously a characteristic of the water-chemical regime of the main loop and the system of circulating (or direct-flow) cooling and has attracted increased attention in recent years. This is due both to the signif-icant suction of cooling water into the condensing steam at the power units of TPPs and NPPs, and to the appearance on the market of new reagents – deposit and corrosion inhibitors. Investigation of the behavior of such substances under conditions of a recirculating cooling system is a complex task, the solution of which depends on many factors. The purpose of the scientific research was to develop a methodology for instrumental (automated) control based on measurements of electrical conductivity ( and H) and pH, which makes it possible to reduce the number of controlled parameters of circulating water, to increase the information content of the measurement results in terms of the amount of suction of circulating water into condensing steam.The implementation of the task in laboratory conditions was carried out using the experi-mental stand «Installation of reverse osmosis and chemical desalination», which provides the ability to measure the specific electrical conductivity of direct () and H-cationized (H) samples of steam condensate and calculate a number of normalized parameters according to the author's algorithm. A large volume of chemical quality control of the make-up and circulating water in the recirculating cooling system limits the efficiency of research and requires large labor costs. In this case, the method of indirect (calculated) deter-mination of the concentrations of ionic impurities can be used by calculating them according to the author's algorithm using the measured values of electrical conductivity and pH.Two laboratory units are presented: reverse osmosis and chemical desalination; modeling the water regime of recirculating cooling systems. A method is proposed for studying the state of the water-chemical regime of a steam turbine condenser both from the side of steam and from the side of cooling water. Examples of using the methodology for calculating the characteristics of steam condensate and cooling water are given. It is shown that the use of instrumental measurements of specific electrical conductivity and pH makes it possible to reduce the volume of laboratory chemical control of aqueous media, to increase the efficiency and information content of the measurement results.A patent for an invention of the Russian Federation No. 2658020 was obtained for a laboratory installation of reverse osmosis and chemical desalination. A distinctive feature of the installation is the ability to obtain deeply demineralized water with a specific electrical conductivity of less than 0,2 μS / cm with the subsequent preparation of extremely dilute solutions. The second laboratory unit simulates the water regime of recirculating cooling systems and can be used in the operating conditions of the power plant. The scientific novelty of the method for the chemical quality control of steam condensate and circulating water consists in the use of an original author's algorithm, which provides the calculation of a number of standardized indicators based on the measured values of electrical conductivity and pH.