Abstract—
An analysis of water utilization systems at thermal power plants (TPPs) shows that highly mineralized effluent waters are mainly generated at these facilities by their water-treatment plants. Highly mineralized alkali liquid waste is presented by the products from continuous and periodic blowdowns of thermal demineralization systems and drum boilers, by spent anion exchange filter regeneration solutions, and by alkali concentrates from reverse osmosis plants. In view of the fact that the alkali used in technological processes has quite a high cost, it is economically expedient to subject alkali effluents to processing with the extraction of alkali for repeatedly using it in the production cycle. The article presents the results obtained at a TPP from experimental investigations into processing of highly mineralized alkali–salt solutions by means of electromembrane technology. The experimental investigations were carried out using the EMA-100 laboratory electromembrane apparatus and included two series of tests: a sequential diffusion–dialysis extraction with concentration by electrodialysis and a single-stage concentration by electrodialysis. As a result, a concentrated alkali solution and partially demineralized softened water were obtained. An analysis of the qualitative and quantitative compositions of the obtained products has shown the effectiveness of the proposed electromembrane processing arrangements, because an alkali solution suitable for its repeated use in the TPP water-treatment cycle was obtained in both series of tests. However, it should be borne in mind that single-stage concentration by electrodialysis is a more economically efficient and simple method, which provides high throughput and yields solutions containing satisfactorily separated alkali and salt components.
Similar content being viewed by others
REFERENCES
A. I. Abramov, D. P. Elizarov, A. N. Remezov, A. S. Sedlov, L. S. Sterman, and V. V. Shchishchenko, Improving the Environmental Safety of Thermal Power Plants (Mosk. Energ. Inst., Moscow, 2001) [in Russian].
N. D. Chichirova, A. A. Chichirov, and T. F. Vafin, Electromembrane Technologies in Power Engineering: Monograph (Kazan. Gos. Energ. Inst., Kazan, 2012) [in Russian].
I. A. Malakhov, V. E. Kosmodamianskii, A. M. Khramchikhin, and G. I. Malakhov, “Recovery of acid-alkaline waste waters from chemical demineralization plants at thermal power stations,” Therm. Eng. 47, 585–592 (2000).
E. V. Veselovskaya, O. V. Lukonina, and A. G. Shishlo, “Modern problems of reconstructing water treatment units of cogeneration enterprises,” Izv. Vyssh. Uchebn. Zaved. Sev.-Kavk. Region. Ser.: Tekh. Nauki, No. 2 (166), 63–66 (2012).
A. Yu. Vlasova, N. D. Chichirova, A. A. Chichirov, A. A. Filimonova, and S. M. Vlasov, “Resource-saving technology of neutralization and purification of acidic and hard highly mineralized liquid wastes of ion-exchange water treatment units at thermal power plants,” Voda Ekol.: Probl. Resheniya, No. 2 (20), 3–17 (2017).
A. S. Kopylov, V. M. Lavygin, and V. F. Ochkov, Water Treatment in Power Engineering (Mosk. Energ. Inst., Moscow, 2003) [in Russian].
V. V. Shishchenko, A. S. Sedlov, I. P. Il’ina, S. V. Sidorova, D. R. Khaziakhmetova, and Yu. E. Pashchenko, “Experience from the development of low-waste water consumption systems at thermal power plants,” Therm. Eng. 52, 297–301 (2005).
V. V. Shishchenko and F. R. Khaziakhmetova, “Ways to reduce water consumption and wastewater in thermal power plants,” Energosberezhenie Vodopodgot., No. 2, 14–17 (2010).
N. D. Chichirova, A. A. Chichirov, A. A. Filimonova, and S. R. Saitov, “Enhancing the ecological and operational characteristics of water treatment units at TPPs based on baromembrane technologies,” Therm. Eng. 64, 920–930 (2017). https://doi.org/10.1134/S0040601517120023
G. I. Malakhov and I. I. Borovkova, “Schemes of water preparation for high and medium pressure boilers with saline waste disposal,” Energosberezhenie Vodopodgot., No. 6, 2–5 (2007).
T. F. Vafin and A. A. Chichirov, “Installation for industrial wastewater treatment and production of a concentrated alkaline solution and softened salt solution,” RF Patent No. 121500, Byull. Izobret., No. 30 (2012).
N. D. Chichirova, A. A. Chichirov, A. I. Lyapin, A. I. Minibaev, Yu. I. Silov, and L. I. Tolmachev, “Electromembrane recycling of highly mineralized alkaline blowdown water from evaporative water treatment plants at thermal power stations,” Therm. Eng. 63, 1046–1050 (2016).
Author information
Authors and Affiliations
Corresponding author
Additional information
Translated by V. Filatov
Rights and permissions
About this article
Cite this article
Chichirov, A.A., Chichirova, N.D., Filimonova, A.A. et al. Laboratory Investigations of Processing Highly Mineralized Alkali Solutions by Means of Electromembrane Technology. Therm. Eng. 66, 527–532 (2019). https://doi.org/10.1134/S0040601519070036
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S0040601519070036