Development of the Technologies for Stabilization Treatment of the Water of the Recycling Cooling Systems at Thermal Power Plants
A turbine-condensate cooling system is one of the less stable and most hard-to-control systems of maintaining optimal water chemistry. A laboratory recycling cooling water test facility, UVO-0.3, was developed for physical simulation of innovative zero-discharge water chemistry conditions and improvement of technological flowcharts of stabilization treatment of the initial and circulating water of the recycling cooling systems at thermal power plants. Experiments were conducted in the UVO-0.3 facility to investigate the processes that occur in the recycling water supply system and master new technologies of stabilization of the initial and circulating water. It is shown that, when using untreated initial water, scaling cannot be prevented even under low concentration levels. The main reason for the activation of scale depositing is the desorption of carbon dioxide that results in alkalization of the circulating water and, as a consequence, a displacement of the chemical reaction equilibrium towards the formation of slightly soluble hardness ions. Some techniques, viz., liming and alkalization of the initial water and the by-pass treatment of the circulating water, are considered. New engineering solutions have been developed for reducing the amount of scale-forming substances in the initial and circulating water. The best results were obtained by pretreating the initial water with alkalizing agents and simultaneously bypassing and treating part of the circulating water. The obtained experimental data underlie the process flowcharts of stabilization treatment of the initial and circulating TPP water that ensure scale-free and noncorrosive operation and meet the corresponding environmental requirements. Under the bypassing, the specific rates of the agents and the residual hardness are reduced compared with the conventional pretreatment.
Keywordsthermal power plant cooling tower laboratory facility zero liquid discharge technologies recycling water supply system stabilization water treatment
Unable to display preview. Download preview PDF.
- 1.J. Bostjancic and R. Ludlum, “Getting to zero discharge: How to recycle that last bit of really bad wastewater,” GE Water & Process Technologies Technical Paper No. TP1041EN (General Electric, 2013). https://www.gewater.com/applications/zero-liquid-discharge-zld.Google Scholar
- 3.S. D. Strauss, “Zero discharge firmly entrenched as a power plant design strategy,” Power 138, 41–48 (1994).Google Scholar
- 5.Amendments to the Federal Law “On Protection of the Environment,” RF Federal Law No. 219-FZ of July 21, 2014 (December 29, 2014 edition).Google Scholar
- 6.Yu. F. Bondar’, “Water chemistry optimization in recycling cooling systems with cooling towers,” Energosberezhenie Vodopodgot., No. 3, 8–10 (2008).Google Scholar
- 7.A. A. Chichirov, N. D. Chichirova, M. A. Volkov, and A. I. Murtazin, “Monitoring of physico-chemical processes in the recycling cooling system of Naberezhnye Chelny CHPP,” Izv. Vyssh. Uchebn. Zaved. Probl. Energ., No. 3–4, 146–150 (2010).Google Scholar
- 9.N. V. Gusinskaya and R. N. Nigmatullin, “The thermal efficiency of evaporative cooling towers,” Therm. Eng. 48, 682–686 (2001).Google Scholar
- 10.S. V. Tikhonov and O. S. Nikolaeva, “Numerical modeling of processes of convective heat-mass exchange during overflow of the water surface by wet air,” Izv. Vseross. Nauchno-Issl. Inst. Gidrotekh. im. B. E. Vedeneeva 240, 230–238 (2002).Google Scholar
- 11.A. M. Rozen, E. I. Martyushin, and V. M. Olevskii, Scale-Up in Chemical Technology: Development of Industrial Equipment by Method of Hydrodynamic Modeling (Khimiya, Moscow, 1980) [in Russian].Google Scholar
- 12.SanPiN 220.127.116.114-01. Potable Water. Hygienic Requirements for Water Quality of Central Potable Water Supply Systems. Quality Control (Minzdrav Rossii, Moscow, 2002). http://docs.cntd.ru/document/901798042.Google Scholar