Implementation of digital automated control systems at electrolytic copper refining plants in Vietnam

The work aims to develop digital control and management systems of copper electrolytic refining processes when addressing energy efficiency issues. Thermal imaging scanners can be used to monitor the process state of an electrolytic cell. In this regard, the experience in the automation and control systems of OJSC Novgorod Metallurgical Plant was considered. Mathematical research methods and a stochastic model developed in the MatLab software were used. This model was applied at the Lao Cai copper-smelting plant (Vietnam). The proposed algorithm is based on the temperature variation in electrolyte depending on the heating of cathode and anode sections during short circuits due to dendritic growth, as well as process disturbance time. The algorithm was developed using the Visual BasicScript programming languages. The temperature rise in short circuit areas was recorded using a thermal imaging scanner immediately after the colour change of the cathode surface. It was shown that the duration of a short circuit depends on the amount of sludge deposited in an electrolytic cell. The sludge formed following the destruction of intergrown dendrites contains precious metals. The developed measures, along with those of digitisation, are necessary for effective management, taking into account the functional and kinetic characteristics of the copper refining process. The proposed solutions and control algorithms will allow remote access systems with augmented reality elements when creating a digital twin. This will reduce the specific power consumption by 20 –25% while decreasing the number of electrode short circuits. Controlling the composition and level of electrolyte and sludge will reduce material losses and maintain the concentration of noble metals in the electrolyte. To improve the control quality of automation during the electrolytic production of cathode copper, a number of technical measures were proposed that provide additional points of control to expand the process database. Furthermore, the proportion of manual periodic measurements of process parameters is reduced.

1. Davenport W. G., King M. J., Schlesinger M. E., Biswas A. K. Extractive metallurgy of copper. London: Oxford, Pergamon; 2002, 452 p. Available from: https://www.elsevier.com/books/extractive-metallurgy-of-copper/davenport/978-0-08-044029-3 [Accessed 12th June 2020].

2. Antonov M. A. Method of powder metallurgy for sintering products from copper powders. Metalloobrabotka. 2001;5:48-49. (In Russ.).

3. Selivanov E. N., Popov A. I., Selmenskikh N. I., Lebed A. B. Oxide inclusions in copper during its fire refining. Non-ferrous Metals. 2013;2:19-22.

4. Vol'hin A. I., Eliseev E. I., Zhukov V. P., Smirnov B. N. Anode and cathode copper: physicochemical and technological fundamentals. Chelyabinsk: Yuzhno-Ural'skoe knizhnoe izdatel'stvo; 2001, 431 р. (In Russ.).

5. Levin A. I., Nomberg N. I. Electrolytic refining of copper. Moscow: Metallurgizdat; 1963, 213 р. (In Russ.).

6. Skirda O. I., Ladin N. A., Dyl'ko G. N. Determining electrolyte optimal composition for electrolytic refining of copper. Zapiski Gornogo instituta. 2005;165:170-171. (In Russ.).

7. Gron D. N., Gorensky B. M. Information-operating system process of electrolytic refinement of copper. Zhurnal Sibirskogo federal'nogo universiteta. Tekhnika i tekhnologiya = Journal of Siberian Federal University. Engineering & Technologies. 2009;2(3):301-310. (In Russ.).

8. Gron' D. N., Lyubanova A. Sh., Chencov S. V. Improved management of the process of electrolytic refining of copper with the help of decision support systems. Fundamental'nye issledovaniya. 2013;8-4:822-827. Available from: http://www.fundamental-research.ru/ru/article/view?id=32003 [Accessed 9th June 2020]. (In Russ.).

9. Mansurova O. K., Chitkova Ya. V. Control and management of interelectrode distance in electrolytic copper refining. Sovremennaya nauka: aktual'nye voprosy, dostizheniya i innovacii: sbornik statej VII Mezhdunarodnoj nauchno-prakticheskoj konferencii = Modern science: relevant issues, achievements and innovations: collected articles of VII International scientific and practical conference. 5 June 2019, Penza. Penza: Nauka i Prosveshchenie; 2019, vol. 2, р. 268-272. (In Russ.).

10. Gavrilenko A. N., Staryh R. V., Habibullin I. H., Matuhin V. L. 63.65 Cu NMR method in the local field when studying ore copper concentrates. Izvestija vysshih uchebnyh zavedenij. Fizika = Russian Physics Journal. 2014;57(9):31-35. (In Russ.).

11. Moloshag V. P., Kolotov S. V., Gulyaeva T. Ya. New data on copper and silver sulfides in ores of the Urals p yrite deposits. Ural'skij mineralogicheskij sbornik . 1995;5:223-231. (In Russ.).

12. Distler V. V., Kryachko M. A., Yudovskaya V. V. Formation conditions of platinum-group metals in chromite ores of the Kempirsai ore field. Geologiya rudnyh mestorozhdenij. 2003;45(1):44-74. (In Russ.).

13. Stepanov V. A., Gvozdev V. I., Truhin Yu. P., Kungurova V. E., Molchanova G. B. Minerals of precious and rare metals in ores of Shanuchskoye copper-nickel deposit (Kamchatka). Zapiski Rossijskogo mineralogicheskogo obshchestva. 2010;139(2):43-58. (In Russ.).

14. Bulatov K. V., Zhukov V. P. Technological capabilities for metallurgical processing of industrial products in polymetallic ore preparation and copper smelting slag depletion in the Pobeda smelting unit. Vestnik Irkutskogo gosudarstvennogo tehnicheskogo universiteta = Proceedings of Irkutsk State Technical University. 2020;24(2):421-433. (In Russ.). https://doi.org/10.21285/1814-3520-2020-2-421-433.

15. Zhmurova V. V., Nemchinova N. V., Vasiliev A. A. Removal of copper and lead from gold-bearing сathode deposits by hydrochemical treatment. Tsvetnye Metally. 2019;8:67-74. (In Russ.). https://doi.org/10.17580/tsm.2019.08.07.

16. Schipper B. W., Lin H.-C., Meloni M. A., Wansleeben K., Heijungs R., Van der Voet E. Estimating global copper demand until 2100 with regression and stock dynamics. Resources, Conservation & Recycling. 2018;132:28-36. https://doi.org/10.1016/j.resconrec.2018.01.004.

17. Mazyrin V. M. Vietnam’s economy is on the rise: trends of 2013-2014. V'etnamskie issledovaniya. 2015;5:182-207.

18. Hannula P.-M., Khalid M. K., Janas D., Yliniemi K., Lundström M. Energy efficient copper electrowinning and direct deposition on carbon nanotube film from industrial wastewaters. Journal of Cleaner Production. 2019;207:1033-1039. https://doi.org/10.1016/j.jclepro.2018.10.097.

19. Alexandrova T. A., Gorlenkov D. V., Romanova N. A. Researching of influence of tungsten, silicon and impurities oxidation on electrolytic dissolution of Cu-Zn and Fe-Ni-CO anodes. Periódico Tchê Química. 2017;14(28):9-17.

20. Shalamov A. V., Mazein P. G. Neural networks as a new approach to technological equipment control. Izvestiya Chelyabinskogo nauchnogo centra. 2003;1:60-64. (In Russ.).

21. Kadyrov E. D. Integrated automated process control system of pyrometallurgical copper production. Zapiski Gornogo Instituta. 2011;192:120-124. (In Russ.).

22. Litvinenko V. S., Telyakov N. M., Gorlenkov D. V. Extraction method of noble metals from radio-electronic industry waste. Patent RF, no. 2357012; 2009. (In Russ.).

23. Telyakov A. N., Gorlenkov D. V., Aleksandrova T. A., Shmidt D. V., Zakirova A. I. Extraction method of noble metals from radio-electronic industry waste. Patent RF, no. 2553320; 2015. (In Russ .).