The effect of CaO and MgO addition and cooling rate on stability of slag obtained after jarosite and neutral leaching residue treatment in the Waelz process
 
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1
Innovation Center of the Faculty of Technology and Metallurgy in Belgrade, University of Belgrade, Karnegijeva 4, 11020 Belgrade, Serbia
2
Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11020 Belgrade, Serbia
3
Innovation center of the Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, 11000 Belgrade, Serbia
4
Institute for Technology of Nuclear and Other Mineral Raw Materials, University of Belgrade, Franse d’Eparea 86, 11000 Belgrade, Serbia
 
Physicochem. Probl. Miner. Process. 2018;54(2):484–495
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ABSTRACT:
Jarosite and Neutral Leaching Residue (NLR) are the greatest environmental problems of hydrometallurgical zinc production due to their high quantity and hazardous content. Pyrometallur-gical processes, such as the Waelz process, could be applied to recover valuable metals present in this waste. The paper investigates the possibility of forming environmentally stable Waelz slag after the Waelz process of jarosite and NLR. Waelz slag, obtained using CaO as a conventional alkaline additive in the Waelz process, showed high As and Sb release after the EN 12457-4 standard leaching test. Multiphase equilibrium composition calculations indicated that As and Sb were present as volatile and migratory species in the slag. In order to obtain Waelz slag with more stable matrices that would encapsulate and immobilize pollutants, MgO additions to CaO and different cooling conditions of the slag were further investigated. The efficiency of modification in additives composition and cooling conditions was assessed by EN 12457-4 leaching test and chemical and microstructural characterization (XRF and SEM-EDS analyses) of the Waelz slags. The results show that addition of MgO does not reduce the efficiency of the process, even more it increases leaching resistance of the slags. Concentrations of all investigated metals (As, Ba, Cu, Mo, Pb, Sb, Zn) after the leaching test were below defined limits for non-hazardous waste. Microstructural analyses revealed that MgO remained inert during Waelz process, and thus favoring the formation of amorphous stable structure, which was enhanced by increased cooling rate. All investigated Waelz slags with MgO additions are suitable for further use or safe disposal.
CORRESPONDING AUTHOR:
Dragana Radovanovic   
Innovation Center of the Faculty of Technology and Metallurgy in Belgrade, University of Belgrade, Karnegijeva 4, 11020 Belgrade, Serbia, Karnegijeva 4, 11020 Belgrade, Serbia
 
REFERENCES (27):
1. BARNA, R., BAE, H., MEHU, J., VAN DER SLOOT, H., MOSZKOWICZ, P., DESNOYERS, C., 2000, Assessment of chemical sensitivity of Waelz slag, Waste Manage. 20, 115 – 124.
2. BASTURKCU, H., ACARKAN, N., 2017, Selective nickel-iron separation from atmospheric leach liquor of a lateritic nickel ore using the para-goethite method, Physicochem. Probl. Miner. Process. 531, 212 − 226.
3. BAT, European Commission, 2014, Best available techniques reference document for the non-ferrous metals industries, Industrial Emissions Directive 2010/75/EU, Final Draft.
4. BAT, European Commission, 2016, Best available techniques conclusions for the non-ferrous metals industries, Commission Implementing Decision 2016/1032/EU.
5. CONNER, J.R., HOEFFNER, S.L., 1998, A critical review of stabilization/solidification technology, Crit. Rev. Environ. Sci. Technol. 28, 397 – 462.
6. DAUGHERTY, K.E., SAAD, B., WEIRICH, C., EBERENDU, A., 1983, The glass content of slag and hydraulic activity, Silic. Ind. 4, 107 – 110.
7. EN 12457-4, 2002, Characterization of waste - Leaching - Compliance test for leaching of granular waste materials and sludges - Part 4: One stage batch test at a liquid to solid ratio of 10 l/kg for materials with particle size below 10 mm (without or with size reduction).
8. FLORES, M., PATIÑO, F., PALACIOS, E., REYES, I., REYES, M., FLORES, V., JUÁREZ, J., PANDIYAN, T., 2016, The behavior of arsenic during the thermal and chemical decomposition of the ammonium–arsenic jarosite, Preprints, doi:10.20944/preprints201610.0059.v1.
9. FROST, R., WILLS, R., WEIER, M., MUSUMECI, A., MARTENS, W., 2005, Thermal decomposition of natural and synthetic plumbojarosites: Importance in ‘archeochemistry’, Thermochim. Acta. 432, 30 – 35.
10. HU, H., LIU, H., CHEN, J., LI, A., YAO, H., LOW, F., ZHANG, L., 2015, Speciation transformation of arsenic during municipal solid waste incineration, P. Combust. Inst. 35, 2883 – 2890.
11. JU, S. , ZHANG, Y., ZHANG, Y., XUE, P., WANG, Y., 2011, Clean hydrometallurgical route to recover zinc, silver, lead, copper, cadmium and iron from hazardous jarosite residues produced during zinc hydrometallurgy, J. Hazard. Mater. 192, 554 - 558.
12. KARIMIAN, N., JOHNSTON, S.G., BURTON, E.D., 2017, Antimony and arsenic behavior during Fe(II)-induced transformation of jarosite, Environ. Sci. Technol. 51, 4259 – 4268.
13. KEROLLI-MUSTAFA, M., MANDIĆ, V., ĆURKOVIĆ, L., ŠIPUŠIĆ, J., 2016, Investigation of thermal decomposition of jarosite tailing waste, A prerequisite for comprehensive jarosite reuse and waste minimization, J. Therm. Anal. Calorim. 123, 421 – 430.
14. LEE, Y.S., MIN, D.J., JUNG, S.M. YI, S.H., 2004, Influence of basicity and FeO content on viscosity of blast furnace type slags containing FeO, ISIJ International. 44, 1283 – 1290.
15. MILLS, S., MADSEN, I., GREY, I., BIRCH, W., 2009, In situ XRD study of the thermal decomposition of natural arsenian plumbojarosite, Can. Mineral. 47, 683 – 696.
16. MOMBELLI, D., MAPELLI, C., BARELLA, S., DI CECCA, C., LE SAOUT, G., GARCIA-DIAZ, E., 2016, The effect of chemical composition on the leaching behaviour of electric arc furnace (EAF) carbon steel slag during a standard leaching test, Journal of Environmental Chemical Engineering. 4,1050 – 1060.
17. MOMBELLI, D., MAPELLI, C., BARELLA, S., GRUTTADAURIA, A., DI LANDRO, U., 2015, Laboratory investigation of Waelz slag stabilization, Process Saf. Environ. 94, 227 – 238.
18. MOMBELLI, D., MAPELLI, C., BARELLA, S., GRUTTADAURIA, A., LE SAOUT, G., GARCIA-DIAZ, E., 2014, The efficiency of quartz addition on electric arc furnace (EAF) carbonsteel slag stability, J. Hazard. Mater. 279, 586 – 596.
19. MOORS, A., DIJKEMA, G., 2006, Embedded industrial production systems, Lessons from waste management in zinc production, Technol. Forecast Soc. Change. 73, 250 – 265.
20. MULTANI, R., FELDMANN, T., DEMOPOULOS, G., 2016, Antimony in the metallurgical industry: A review of its chemistry and environmental stabilization options, Hydrometallurgy. 164, 141 – 153.
21. NAZARI, A.M., RADZINSKI, R., GHAHREMAN, A., 2016, Review of arsenic metallurgy: Treatment of arsenical minerals and the immobilization of arsenic, Hydrometallurgy, http://dx.doi.org/10.1016/j. hydromet.2016.10.011.
22. PATIÑO, F., FLORES, M., REYES, I., REYES, M., HERNÁNDEZ, J., RIVERA, I., JUÁREZ, J., 2013, Alkaline decomposition of synthetic jarosite with arsenic, Geochem. T. 14, 1 – 9.
23. PRAJSNAR, R., CZERNECKI, J., MICHALSKI, R., ADAMKIEWICZ, L., CYBULSKI, A., BEDNAREK, P., SZUBA, S., KULAWIK, S., KAPIAS, P., ZAJACZKOWSKI, A., BRATEK, L., KOZLOWICZ, M., STASZEWSKI, M., KOLACZ, D., TRACZEWSKI, W., 2015, Laboratory and pilot studies into treatment of Pb/Zn raw materials in Waelz process, Institute of Non-Ferrous Metals, Gliwice, Poland. Report Imn No 7348/15 submitted to Metal Recovery Ltd, Serbia.
24. QUIJORNA, N., DE PEDRO, M., ROMERO, M., ANDRÉS, A., 2014, Characterisation of the sintering behaviour of Waelz slag from electric arc furnace (EAF) dust recycling for use in the clay ceramics industry, J. Environ. Manage. 132, 278 – 286.
25. Rulebook on categories, testing and classification of waste, 56/10, Official Gazette of the Republic of Serbia, 2010; (in Serbian).
26. STOPIĆ, S., FRIEDRICH, B., 2009, Kinetics and mechanism of thermal zinc-ferrite phase decomposition, in : Proceedings of the Europe Metallurgical Conference, 1167–1181.
27. TOSSAVAINEN, M., ENGSTROM, F., YANG, Q., MENAD, N., LIDSTROM LARSSON, M., BJORKMAN, B., 2007, Characteristics of steel slag under different cooling conditions, Waste Manage. 27,1335 – 1344.
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