Air Protection of Working Zone against Fine-Dispersed Lithium Compounds Dust by Its Return to the Production Cycle

Based on the analysis of experimental data, it was found that the main source of lithium compounds dust into the environment is the vacuum-drying cabinets and presses used in the technological process at the stage of manufacturing chemosorbents over which forced exhaust ventilation is installed, effectively removing the dust of lithium com-pounds from the air of the working area (up to a value of 0.014 mg/m3 which is 30% less than MPC). We have used the chemical and qualitative X-ray phase analysis methods to determine the chemical composition of dust. It follows from the results obtained that the main components in the dust composition are lithium hydroxide monohydrate and lithium hydroxide – the substances used in technological processes as the main raw material and have a sufficiently high cost. The article analyzes the dispersed composition of dust and its concentration in the air of the working area. It was found that the bulk of the dust particles are much larger than 10 microns, and the dust concentration of lithium compounds is not more than 4.6–6.0 mg/m3 throughout the process. Several systems of air purification from lithium compounds dust are considered. Based on the analysis of the results obtained, the purification system consisting of a battery cyclone and subsequent air flow bubbling through the water layer is proposed. The system allows us to reduce the dust concentration to a value of 0.017 mg/m3 which is 15% less than the MPC for hydroxide and lithium peroxide. It is shown experimentally that the dust of lithium compounds obtained as a result of removal from the air of the working zone can be used in the technological cycle of synthesis of lithium peroxide providing the possibility of obtaining a final product with a content of the base material up to 93.3% by weight. This scheme of removal of lithium compounds dust and its subsequent return to the production cycle can be used in the development of initial data for the design of environmentally friendly lithium peroxide production technology.

1. Voronin G.I., Polivoda A.I. Life support for spacecraft crews (Zhizneobespechenie ekipazhei kosmicheskikh korablei). – Moscow: Mechanical Engineering, 1967; p. 36 (in Russ.).

2. Petroctlli A., Capolesto A. Some notes on the use of superoxides in the regenerative air system. Aerospase Med., 1964;31:440 (in Eng.).

3. Presti J., Wallman H., Petroctlli A. Superoxide life support system for submersibles. Undersea Technol., 1967;8:20 (in Eng.).

4. Harmful substances in industry (Vredny`e vesh-chestva v promy`shlennosti). Edited by Lazarev N.V. Moscow: Chemistry Publ., 1977, vol. 3, p. 321 (in Russ.).

5. Franke Z. Chemistry of toxic substances (Himiia otravlyayushchikh veshchestv). Moscow: Chemistry Publ., 1973, vol. 1, p. 411 (in Russ.).

6. Kopytov Yu. F., Bulaev N. A., Ferapontova L. L. Protection of the environment from lithium dust (Zashchita okruzhayushchei sredy ot pyli soedinenii litiia). Proceedings of the All-Russian Scientific Congress “Fundamental science a resource for preserving the health of healthy people”. Tambov, RAS Publ., 2008; p. 101–103 (in Russ.).

7. Uzhov V.N., Waldberg A.Yu., Myagkov B.I., Reshidov I.K. Purification of industrial gases from dust (Ochistka promyshlennykh gazov ot pyli). Moscow: Science, 1981; p. 423 (in Russ.).

8. Kouzov P.A., Malgin A.D., Scriabin G.M. Cleaning from dust gases and air in the chemical industry (Ochistka ot pyli gazov i vozduha v himicheskoi promyshlennosti.) Leningrad: Chemistry Publ., 1982; p. 267 (in Russ.).

9. Rodionov A.I., Kuznetsov Yu.P., Zenkov V.V., Soloviev G.S. Equipment, facilities, fundamentals of designing chemical and technological processes for protecting the biosphere from industrial emissions (Oborudovanie, sooruzheniya, osnovy proektirovaniya himiko – tekhnologicheskikh protsessov zashchity biosfery ot promyshlennykh vybrosov). Moscow: Chemistry Publ., 1985; 432 p. (in Russ.).

10. Izraelson Z.I., Mogilevskaya O. Ya., Suvorov S. V. Issues of occupational health and occupational pathology when working with rare metals (Voprosy gigieny truda i professionalnoi patologii pri rabote s redkimi metallami). Moscow: Medicine Publ., 1973; 303 p. (in Russ.).

11. Smith N.W., Walkenhorst W.L. Lithium hydroxide. Amer. Ind. Hyg. Assoc. J., 1964;25(4):424–426.

12. Williams R.F. Threshold Limit Values. American Conference of Governmental Industrial Hygienists. N.Y., 1974; pp. 94–99 (in Eng.).

13. Brunere V.Ya., Dokuchaeva A.N. Determination of oxygen in peroxide compounds (Opredelenie kisloroda v perekisny`kh soedineniiakh). Izv. AN Latv. SSR. Ser. Chemical, 1990, no. 6, p. 693 (in Russ.).

14. Seyb E., Kleinberg J. Determination of superoxid oxygen. J. Am. Chem. Soc., 1951;73:2308.

15. Alekseevskiy G.V., Golts R.K., Musakin A.A. Quantitative analysis (Kolichestvennyi analiz). Мoscow: Goskhimizdat Publ., 1955; 558 p. (in Russ.).

16. Guidelines for the determination of harmful sub-stances in the air (Metodicheskie ukazaniya na opredelenie vrednykh veshchestv v vozdukhe). Мoscow: TSRIA “Morflot” Publ., 1981; pp. 235–239 (in Russ.).

17. Ferapontov Yu.A., Ulyanova M.A., Zhdanov D.V. Evaluation of the dispersed composition of peroxide compounds of alkali metals (Otsenka dispersnogo sostava perekisnykh soedinenii shchelochnykh metallov). Chemical Technology, 2008;9(1):1–6 (in Russ.).

18. Ferapontov Yu.A., Ulyanova M.A., Sazhneva T.V. Obtaining lithium peroxide in a field of ultrahigh frequency (Poluchenie peroksida litiya v pole sverkhvysokoi chastoty). Chemical Technology, 2007;8(5):193–196 (in Russ.).

19. Ferapontov Yu.A., Ulyanova M.A., Sazhneva T.V. Pat. Of the Russian Federation No. 2322387. IPC S01B 15/043. The method of obtaining lithium peroxide (Sposob polucheniya peroksida litiya. Publ. 2008 (in Russ.).

20. Ferapontov Yu.A., Ulyanova M.A., Sazhneva T.V. Crystallization conditions for Li2O2 ∙ H2O in the ternary system LiOH – H2O2 – H2O (Usloviya kristallizatsii Li2O2∙H2O v troinoi sisteme LiOH – H2O2 – H2O). WNH, 2008;53(10):1749–1754 (in Russ.).

21. Nefedov R., Posternak N., Ferapontov Yu. Kinetics of Lithium Peroxide Monohydrate Thermal Decomposition. AIP Conference Proceedings, 2017;1899(1):020013-1–020013-6 (in Eng.).

22. Nefedov R., Ferapontov Y. Synthesis of Lithium Peroxide from Hydrogen Peroxide and Lithium Hydroxide in Aqueous-Organic Medium: Wasteless Technology. MATEC Web of Conferences, 2017;96:Article Number 00004 (in Eng.)