Electrolytic properties of carbonic acid solutions and innovative methods of operational control of water quality such as condensation at TPP
https://doi.org/10.12737/16069
Abstract
The work objective is to improve the operational conductometric vapor quality control at the thermal power plants. To this end, methods identifying СО2 concentrations in the vapor under the neutral aqueous-chemical mode without ammonia addition are developed. The technique of measuring the steam condensate conductivity at the operating pressures of steam generators and at different temperatures is used. The implementation of this method with the use of a special device significantly reduces the control response rate and differentiation of impurities. The experimental data on the first apparent dissociation constants and the limiting equivalent conductance of the carbonic acid, dissociation constants, and the limiting equivalent conductance of NaCl in the liquid phase on the saturation line are analyzed. On the basis of this analysis, an error in determining СО2 concentration and the impurities in vapor in the form of NaCl by the proposed method is estimated. The approximation error for the dependencies describing the dissociation constants behavior, and the limiting equivalent conductance of the carbonic acid, which can be used in the calculation of the concentrations by the proposed methodology, as well as during the organization and management of water chemistry, is estimated.
References
1. Voronov, V.N., Petrova, T.I. Vodno-khimicheskie rezhimy TES i AES. [Water chemistry of TPP and NPP.] Mos cow: Izdatel'skiy dom MEI, 2009, 238 p. (in Russian).
2. Ministry of Energy of the Russian Federation. Ministerstvo energetiki Rossiyskoy Federatsii. Pravila tekhnicheskoy ekspluatatsii elektricheskikh stantsiy i setey RF SO 153-34.20.501-2003. [Operational regulation of power plants and networks of the Russian Federation СО 153-34.20.501-2003.] Moscow: Energoservis, 2003, 145 p. (in Russian).
3. Larin, B.М., Bushuyev, E.N. Osnovy matematicheskogo modelirovaniya khimiko-tekhnologicheskikh protsessov obrabotki teplonositelya na TES i AES. [Fundamentals of mathematical modeling of chemical-technological coolant treatment at TPP and NPP.] Moscow: Izdatel'skiy dom MEI, 2009, 306 p. (in Russian).
4. Martynova, О.I. Povedenie organiki i rastvorennoy uglekisloty v parovodyanom trakte elektrostantsiy. [The Behavior of Organic Compounds and Dissolved Carbon Dioxide in the Steam-Water Path of Power Stations.] Thermal Engineering, 2002, no. 7, pp. 67–70 (in Russian).
5. Bushuyev, E.N. Issledovanie i matematicheskoe modelirovanie khimiko-tekhnologicheskikh protsessov vodoobrabotki na TES: dis. … d-ra tekhn. nauk. [Investigation and mathematical modeling of chemical-technological processes of water treatment at TPP: Dr.Sci. (Eng.) diss.] Ivanovo, 2010, 359 p. (in Russian).
6. Shcherbakov, V.N. Issledovanie elektrofizicheskikh svoystv vodnykh teplonositeley pri vysokikh parametrakh: dis. … kand. tekhn. nauk.[Study on electrophysical properties of water coolants at high settings: Cand.Sci. (Eng.) diss.] Moscow, 1980, 204 p. (in Russian).
7. Timrot, D.L., et al. Konduktometricheskiy datchik: a. s. 958943 SSSR : MKI4 G01N 27/02. [Conductivity sensor.] Inventor’s Certificate no. 958943 USSR МКИ4 G01N 27/02, 1982 (in Russian).
8. Shcherbakov, V.N. Sovershenstvovanie konduktometricheskogo kontrolya kachestva kondensata para pri termicheskoy ochistke vod. [Improving conductometric quality control of steam condensate under thermal water treatment.] Vestnik of DSTU, 2013, vol. 13, no. 3/4 (72/73), pp. 117–124 (in Russian).
9. Efimov, N.N., et al. Eksperimental'noe i teoreticheskoe obosnovanie novogo metoda kontrolya kachestva rabochego tela v konturakh TES i AES.[Experimental and Theoretical Study of a New Method for Monitoring the Quality of the Working Fluid in the Contours of Thermal and Nuclear Power Plants.] Izvestiya vuzov. Severo-Kavkazskiy region. Technical Sciences.2012, no. 3 (166), pp. 28–32 (in Russian).
10. Lukashov, Y. М. Eksperimental'no-teoreticheskoe obosnovanie novykh metodov kontrolya kachestva para i vody sovremennykh teploenergeticheskikh ustanovok : dis. … d-ra tekhn. nauk. [Experimental and theoretical justification of new methods of water and vapor quality control of modern thermal power plants: Dr.Sci. (Eng.) diss.] Moscow, 1981. — 412 с. (in Russian).
11. Simanova, A.M., ed. Novyy spravochnik khimika i tekhnologa : v 12 t. T. 7. Khimicheskoe ravnovesie. Svoystva rastvorov. [New reference guide for a chemist and technologist: in 12 vol. Vol. 7. Chemical equilibrium. Properties of solutions.] St. Petersburg: Professional, 2004, 998 p. (in Russian).
12. Damaskin, B.B., Petriy, O.A., Tsirlina, G.A. Elektrokhimiya. [Electrochemistry.] Moscow: Khimiya; Kolos S, 2006, 672 p. (in Russian).
13. Dobosh, D. Elektrokhimicheskie konstanty. Spravochnik dlya elektrokhimikov. [Electrochemical constants. Reference guide for electrochemists.] Moscow: Mir, 1980, 365 p. (in Russian).
14. Stefansson, A., Benezeth, P., Schott, J. Carbonic acid ionization and the stability of sodium bicarbonate and carbonate ion pairs to 200oC — A potentiometric and spectrophotometric study. Geochimica et Cosmochimica Acta, 2013, vol. 120, pp. 600–611.
15. Ryzhenko, B.N. Opredelenie konstant dissotsiatsii ugol'noy kisloty i raschet stepeney gidroliza SO32- i NSO3-ionov v rastvorakh karbonatov i bikarbonatov pri povyshennykh temperaturakh. [Determination of dissociation constants of carbonic acid, and calculation of hydrolysis degrees of СО3 2- and НСО3- ions in carbonate and bicarbonate solutions at high temperatures.] Geochemistry, 1963, no. 2, pp. 137– 148 (in Russian).
16. Read, A.-J. The First Ionization Constant of Carbonic Acid from 25 to 250o C and to 2000 bar. Journal of Solution Chemistry, 1975, vol. 4, no. 1, pp. 53–70.
17. Dickson, A.G., Millero, F.J. A comparison of the equilibrium constants for the dissociation of carbonic acid in seawater media. Deep-Sea Research Part A. Oceanographic Research Papers. 1987, vol. 34, iss. 10, pp. 1733–1743.
18. Shedlovsky, T., MacInnes, D.-A. The first ionization constant of carbonic acid, 0 to 38 from conductance measurements. Journal of the American Chemical Society, 1935, vol. 57, pp. 1705–1710.
19. Harned, H.-S., Bonner, F.-T. The first ionization of carbonic acid in aqueous solution of sodium chloride. Journal of the American Chemical Society, 1945, vol. 67, pp. 1026–1031.
20. Nakayama, F.-S. Thermodynamic functions for the dissociation of NaHCO30, NaCO3 −, H2CO3 and HCO3 − .Journal of Inorganic and Nuclear Chemistry, 1971, vol. 33, pp. 1287–1291.
21. Park, S.-N., et al. Spectrophotometric measurement of the first dissociation constants of carbonic acid at elevated temperatures. Journal of the Chemical Society Faraday Transactions, 1998, vol. 94, iss. 10, pp. 1421–1425.
22. Millero, F., et al. The dissociation of carbonic acid in NaCl solutions as a function of concentration and temperature. Geochimica et Cosmochimica Acta, 2007, vol. 71, iss. 1, pp. 46–55.
23. Patterson, C.S., et al. Carbonate equilibrium in hydrothermal systems — first ionization of carbonic acid in NaCl media to 300o C. Geochimica et Cosmochimica Acta, 1982, vol. 46, iss. 9, pp. 1653–1663.
24. Li, D., Duan, Z. The speciation equilibrium coupling with phase equilibriumin the H2O–CO2–NaCl system from 0 to 250o C, from 0 to 1000 bar, and from 0 to 5 molality of NaCl . Chemical Geology, 2007, vol. 244, iss. 3-4, pp. 730–751.
25. Robinson, R., Stoks, R. Rastvory elektrolitov. [Electrolyte solutions.] Moscow: Inostrannaya literatura, 1963, 425 p. (in Russian).
26. Pervukhin, B.S. Razvitie nauchno-metodicheskikh osnov proektirovaniya konduktometricheskikh priborov kontrolya zhidkostey i razrabotka tekhnicheskikh sredstv ikh metrologicheskogo obespecheniya: avtoref. dis. … d-ra tekhn. nauk. [Development of scientific and methodological foundations of conductometric fluid control devices design and techniques engineering of their metrological assurance: Dr.Sci. (Eng.) diss., author’s abstract.] Barnaul, 2012, 39 p. (in Russian).
27. Shcherbakov, V.N., Vlaskov, G.A. Innovatsionnye elektrofizicheskie metody operativnogo kontrolya kachestva vod tipa kondensata na TES. [Innovative electrophysical methods of operational monitoring of condensate-type water quality at TPP.] Obozrenie prikladnoy i promyshlennoy matematiki, 2014, vol. 21, iss. 5, pp. 764–765 (in Russian).
28. Egoshina, О.V.. Voronov, V.N., Nazarenko, M.P. Sovremennoe sostoyanie sistem khimiko-tekhnologiche-skogo monitoringa na teplovykh stantsiyakh na osnove opyta MEI i NPTs «Element». [Modern State of Cycle Chemistry Monitoring Systems at Thermal Power Stations According to the Experience Gained at the Moscow Power Engineering Institute and Element Research and Production Center.] Thermal Engineering, 2014, no. 3, pp. 39–45 (in Russian).
Review
For citations:
Shcherbakov V.N. Electrolytic properties of carbonic acid solutions and innovative methods of operational control of water quality such as condensation at TPP. Vestnik of Don State Technical University. 2015;15(4):24-30. (In Russ.) https://doi.org/10.12737/16069
Views:
522
Email this article 