Temperature Effect on the Hypergene Mineral Formation Process (the Case of Tailing Dumps of Komsomolsky Tin-Ore District)

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1 Advanced Materials Research Submitted: ISSN: , Vols , pp Accepted: doi: / Online: Trans Tech Publications, Switzerland Temperature Effect on the Hypergene Mineral Formation Process (the Case of Tailing Dumps of Komsomolsky Tin-Ore District) Valentina Zvereva 1, 2, a, Alyona Kostina 1, 2, b, Konstantin Frolov 2, c 1 Far Eastern Federal University: 8, Sukhanova st., Vladivostok , Russian Federation. Tel.: +7(423) ; 2 Far East Geological Institute FEB RAS: 159, Prospekt 100-letiya, Vladivostok , Russian Federation, Tel.: +7(423) a zvereva@fegi.ru, b alyona5vbc@mail.ru, c konstantin.fk@gmail.com Keywords: physicochemical modeling, hypergenesis, tailings, tailing dump, estimation of ecological situation, verification. Abstract. Physicochemical modeling of drainage water in the tailing dumps of Komsomolsky tin ore district in a wide temperature range from -10 to +45 C obtained in the article let to find Eh-pH parameters of micropore solutions from which technogenic and hypergene minerals crystallize. The modeling was made for different ratios host rock sulfides (95:5, 90:10, 80:20 and 60:40). Qualitative and quantitative ionic composition of the solutions was determined and their impact on the surface and ground water of the area was showed. Introduction Long lasting and intensive development of the mining industry in the Komsomolsky district during the last 70 years led to the presence of numerous ditches, pits, tunnels and tailing dumps. It contributed to the creation of mining technogenic system with area of dozens of acres where hypergene processes are activated due to the increase of contact surface of sulfides with the weathering agents. There are two concentrating mills and three tailings dumps (their total area is 80.8 hectares) in the district million tons tailings were stockpiled here. The finely-dispersed tailings mass of Komsomolsky region consists of (%): vein quartz 37.5, tourmaline 12.1, host sedimentary rocks 45 and sulfides (pyrite, pyrrhotite, arsenopyrite, chalcopyrite, galena and sphalerite) 3.8. They contain the following useful components (g/t): Sn 0.2, Cu 0.46, Zn 0.094, Pb 0.123, Ag 1.227, Bi 0.03, As Negative impact of mining systems on the ecosphere in general and on the hydrosphere in particular is shown in many literary sources [1-3 and others]. The main purpose of this work is to assess the impact of technogenic and hypergene processes on hydrosphere in three tailing dumps of the district in a wide temperature range from -10 to +45 º C. Climatic characteristic of the district [4] shows the annual temperature change in a range from -40 to +40 º C. It can greatly increases under sulfides oxidation, so the upper limit was taken five degrees higher. Based on the goal the following tasks were formulated: 1. to research the process of sulfides oxidation in three tailings of the district in the temperature range from -10 to +45 º C; 2. to determine the composition of technogenic minerals crystallized from the solutions of drainage and slime waters; 3. to find the qualitative and quantitative composition of these waters; 4. to assess their impact on the hydrosphere of the district; 5. to verify the data obtained. Research method Physicochemical modeling of technogenic processes occurring in the mining waste was conducted through the "Selektor" PC program. It made possible calculation of the amounts of elements carried out from the tailing dumps into the hydrosphere. The method is based on the minimization of the All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications, (ID: , Pennsylvania State University, University Park, USA-09/04/16,00:30:44)

2 1298 Materials Science, Computer and Information Technology Gibbs energy and estimation of the total and metastable equilibrium in multicomponent heterogeneous systems. In our previous work the modeling was performed at the temperature of +25 ºC [5]. In this research we consider a system with a pressure of 1 atm and temperature range from -10 to +45 ºC. The water-rock ratio was taken as 10:1. The annual rainfall ( kg per 1 m 2 ) and the selected temperature range were taken into account in the modeling. Models were opened to the atmosphere. The chemical composition of the atmosphere (10 kg) was calculated by R. Horne [6]: Ar 3.21, C 0.11, N , O independent (Al, Ar, As, B, C, Ca, Cu, Fe, K, Mg, N, Na, Pb, S, Si, Zn, H, O, e) and 452 dependent components were included in the calculations, from which 360 are dissolved particles, 18 gases and 74 hypogene and hypergene minerals. Results and discussion Mining wastes are presented by pyrite, pyrrhotite, galena, sphalerite, arsenopyrite, chalcopyrite, quartz, tourmaline and other minerals. Modeling of sulfides oxidation in contact with the host rock was carried out for all three tailing dumps (Table 1). The waste composition varies in its different parts, therefore simulated system for each of them were made with ratios of host rock sulfides 95:5, 90:10, 80:20 and 60:40. Hypergene minerals crystallized from concentrated solutions of these models are shown in the Table 2. In the simulated system of Festivalnoye deposit tailing dump copper-tin-type of Solnechnaya concentrating mill (SCM) solutions are similar and have ph values ranging from 6.02 to and Eh volts. Some of them crystallize at all ratios (g): goethite, woodwardite, kaolinite, magnesite, gypsum, hydromuscovite, others in all ratios, except 95:5 (g): scorodite and rostite. Other minerals crystallize only at a certain ratio (g): calcite (95:5), duftite (80:20 and 60:40), alunogen (80:20 and 60:40), starkeyite (60:40) and montmorillonite (90 10). In the simulated system of Solnechnoye deposit tailing dump tin mineralization type of Centralnaya concentrating mill (CCM) solutions are similar and have ph values ranging from 5.98 to and Eh volts. In this temperature range minerals of hypergenesis zone and weathering crust crystallize from such classes as oxides, hydroxides, sulfates, carbonate, silicates, and arsenates. These are minerals of the following cations (g): Fe (goethite and scorodite), Pb and Cu (duftite) and Al (kaolinite, alunogen and rostite), Cu and Al (woodwardite), Mg (starkeyite and magnesite), Ca (gypsum and calcite), K and Al (hydromuscovite), Mg, Al and Fe (montmorillonite). In the simulated system of the third tailing dump where ore processing waste of tin-polymetallic ore type of Perevalnoe deposit were stockpiled parameters of the solutions are similar and have ph values ranging from 6.09 to and Eh volts. In these systems the same hypergene minerals crystallize as in the previous ones but are distinguished by the quantitative characteristic (Table 2). It should be noted that the amount of crystallized minerals in all systems is low at a negative temperature, but the mineralization of these solutions is very high. For example, in the models of CCM tailings dump it is , SCM and the third one g/l. With the temperature increase from 0 up to +20 C mineralization of the solution becomes higher (g/l): at CCM tailings dump from to 22.21, but then decreases to 20.55, SOF to 20.37, at the third one to At temperatures below 0 C the model contain water in a solid form (ice), the content of which varies from to g and its amount decreases with the increase of host rock and decrease of sulfides in the system. Crystallization of some minerals (scorodite, starkeyite and rostite) in the models occurs at subzero temperatures in a range from 0 to -10 C and the other ones (calcite, alunogen, woodwardite, duftite, montmorillonite) at positive numbers from 0 to +45 C. Other minerals (goethite, kaolinite, gypsum, magnesite) crystallize in a large range from -10 to +45 C, but their quantity in the case of negative temperature values is much lower than for the positive ones. Thus crystallization at low temperatures is difficult.

3 Advanced Materials Research Vols Ionic composition of the resulting solutions is presented by the following ions of sulfide elements: As 5 +, CuCO 3 2-, Cu 2+, CuCO 3 0, CuO 0, CuOH +, CuSO 4 0, H 2 AsO 4 -, H 3 AsO 4 0, HAsO 4 2-, HCuO 2 -, HFeO 2 0, FeO +, FeO 2 -, FeOH 2+, HPbO 2 -, HSO 4 -, HZnO 2 -, Pb(CO 3 ) 2 2-, Pb(SO 4 ) 2 2-, Pb 2+, PbHCO 3 +, PbNO 3 +, PbO 0, PbOH +, PbSO 4 0, Zn(CO 3 ) 2 2-, Zn(SO 4 ) 2 2-, Zn 2+, ZnCO 3 0, ZnHCO 3 +, ZnO 0, ZnOH +, ZnSO 4 0, SO Verification made with ionic and mineral composition [1] and comparison of the element contents in the modeled solutions with hydrochemical data on the mine, slime, and drainage waters [2-3] proved the validity of the obtained results. Conclusion Physicochemical modeling of sulfides oxidation has shown that from highly concentrated solutions hypergene minerals of Fe, Cu, Pb, Al, Mg, K and Ca crystallize, that belong to sulfates, carbonates, silicates, arsenates, oxides, and hydroxides classes. The greatest amount of ore elements (Cu, Pb, Zn, S) in the solutions is observed at negative temperatures. In the range of positive temperatures elements content in the aqueous solutions is gradually reduced by an order or two. Simulated drainage water solutions of all tailing dumps are characterized by high concentration (g/l) of S to 9.6, Pb 66.8, Zn 53.6, As 46.6 and Cu Total mineralization of the tailings solutions is (g/l): 20 to 397 for CCM, for SCM and for 3 rd one. If we estimate the impact of each individual tailing dump, the maximum hydrosphere damage is caused by SCM tailing dump and the minimum by CCM. Total removal of elements from all three tailing dumps varies from 61 to 1287 g/l. Physicochemical modeling of the main phases of the drained tailing dumps existence in Komsomolsky tin ore district carried out by authors in the temperature range from -10 to +45 C gives a complete picture of the drainage water formation that flows into the surface water in a dangerous, untreated form. Hydrosphere is exposed to strong anthropogenic stress with S, Zn, Cu, Pb, Fe sulfides elements and B, Mg, K, Na, Ca, Si and Al host rocks elements. Modeling allows assessing the condition of mining technogenic system in space and time, to receive new data for the parameters of modern technogenic minerals and to show their Eh-pH existence conditions. Acknowledgement The research work was supported by the FEB RAS grant number 14-III-В The authors are thankful to PhD Valeriy Bychinsky for his help in the modeling. Table 1 Original composition of hypogene minerals using in the models [%] Mineral Tailing dump SCM CCM Third TD* Sulfides Pyrite FeS Pyrrhotite Fe 1-x S n Arsenopyrite FeAsS Chalcopyrite CuFeS Galena PbS Sphalerite ZnS Host rock Grossular Ca 3 Al 2 [Si 3 O 12 ] Albite Na[AlSi 3 O 8 ] Clinochlore Si 3 Al 2 Mg 5 H 8 O

4 1300 Materials Science, Computer and Information Technology Muscovite KAl 2 [AlSi 3 O 10 ](OH) Biotite NaFe 3 [AlSi 3 O 10 ](OH) Tourmaline NaFe 3 Al 6 [BO 3 ] 3 [Si 6 O 18 ](OH) *Third TD Third tailing dump Table 2 The composition of hypergene minerals in the results of modeling of tailings oxidation in contact with host rock [g] Mineral Tailing dump SCM CCM Third TD Ice H 2 O Goethite FeOOH Magnesite MgCO Calcite CaCO Gypsum CaSO 4. 2H 2 O Starkeyite Mg[SO 4 ]. 4H 2 O Hydromuscovite K[Al 3 Si 3 O 10 ](OH) 2. 4H 2 O Muscovite K[Al 3 Si 3 O 10 ](OH) Quartz SiO Caolinite Al 2 [SiO 3 ] 2 (OH) Woodwardite Cu 4 Al 2 [SO 4 ](OH) 12. H 2 O Rostite Al[SO 4 ](OH). 5H 2 O Alunogen Al 2 [SO 4 ] 3. 18H 2 O Duftite PbCu[AsO 4 ](OH) Scorodite Fe[AsO 4 ]. 2H 2 O Montmorillonite (Na.Ca) 0.33 (Al.Mg) 2 (Si 4 O 10 )(OH) 2 nh 2 O References [1] V.P. Zvereva. Ecological subsequences of hypergene processes at tin deposits of the Far East. Dalnauka: Vladivostok, [2] V.P. Zvereva, L.T. Krupskaya. Anthropogenic Waters in the Komsomolsk, Kavalerovskii, and Dalnegorsk Mining Areas of the Far East and Their Impact on the Hydrosphere. Russian Journal of General Chemistry, 2012, 82 (13) [3] P.V. Elpatevsky, T.N. Lutsenko. The mining complex as the factor of formation of the water chemical composition. Materials: Scientific and practical aspects of extraction of non-ferrous and precious metals (2) [4] G.N. Vitvitskiy. The Far East. Physiographic characteristic. Publishing House of the USSR Academy of Sciences: Moscow, Ch. Climate, [5] A.M. Kostina, V.P. Zvereva, K.R. Frolov, A.D. Pyatakov, A.I. Lysenko. Impact assessment of tin ore tailing dumps of Komsomolsky district of the Far East on the hydrosphere. Chemical Technology, 2012 (5) [6] R. Horne. Marine chemistry. Mir: Moscow, 1972.

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