通过水热浸出实验分别研究了精炼废渣及合成的废渣中2种主要单一矿相12CaO?7Al2O3和2CaO?SiO2的溶解行为，并将二者进行对比分析，探究了LF精炼废渣在水热浸出过程中的溶解行为。结果表明，废渣浸出过程中浸出液的pH?12，且随浸出时间增加，电导率和Ca浓度增加，Al浓度急剧下降，Si浓度低于0.1 mg/L且保持不变；12CaO?7Al2O3浸出过程中，随时间增加，浸出液pH值稳定在约11.3，浸出液中Al浓度增加，Ca浓度略微下降。2CaO?SiO2浸出液中主要为Ca2+，Si浓度低于0.6 mg/L；废渣与单一矿相浸出过程的pH值及Al, Si浓度较接近，可以通过单一矿相的溶解行为研究精炼废渣在水热浸出过程中的溶解行为，但废渣浸出液的Al和Si浓度均低于单一矿相，表明废渣中CaO等其它组分溶解抑制了12CaO?7Al2O3和2CaO?SiO2溶解。
Ladle furnace (LF) refining spent slag is a by-product of molten steel refining process. The reutilization of LF refining slag is rare because of the high content of sulfur in the slag. However, the hydrothermal leaching method can effectively reduce the sulfur content in refining slag and the leached slag has high recycling value. As a composite mineral consisting of a variety of single mineral phases, many components of the refined slag dissolve into the solution during the hydrothermal leaching process, forming a multi-component complex leaching system. It is of great significance to study the dissolution behavior of LF refining slag in hydrothermal leaching process for the recycling of waste residue resources. In order to investigate the dissolution behavior of refining slag, the leaching behavior of LF refining slag and its two main mineral phases (12CaO?7Al2O3 and 2CaO?SiO2) by hydrothermal leaching treatment were studied and the difference between them was compared. The results showed that the pH value of leaching solution was higher than 12 during the leaching process. With the increase of leaching time, both the concentration of Ca and the conductivity of solution increased subsequently, but the concentration of Al decreased sharply. Furthermore, the concentration of Si with a low concentration of less than 0.1 mg/L remained constant. With the increase of time, in the leaching processing of 12CaO?7Al2O3, the pH value of leaching solution was stable with around 11.3, the concentration of Al improved, and the concentration of Ca decreased slightly. Whereas for 2CaO?SiO2, the leaching solution with low concentration of Si (lower than 0.6 mg/L) mainly contained Ca2+. Overall, the pH value and the concentrations of Al and Si of the leaching solution of the slag were close to those of single mineral phase. The dissolution behavior of LF refining slag in hydrothermal leaching process can be studied by the dissolution behavior of single mineral phase. However, the concentration of Al and Si were lower than that of single mineral phase, indicating that the dissolution of 12CaO?7Al2O3 and 2CaO?SiO2 in slag were restricted by the dissolution of CaO and other components.
[1]刘航航，刘朝阳，邵伟.精炼废渣资源循环利用综述[J].炼钢, 2015, 31(2):73-78 [2]Liu H H, Liu Z Y, Shao W.The resource recycling of LF refining slag[J].Steelmaking, 2015, 31(2):73-78 [3]Wang Y , Yang S , Li J , et al. .Cyclic Use of Ladle Furnace Refining Slag for Desulfurization[J].Journal of Sustainable Metallurgy, 2016, :1-6 [4]王维，胡尚雨.冷态渣用于脱硫的研究[J].炼钢, 2011, 27(2):48-51 [5]Wang W, Hu S Y.Study on using LF cold slag for desulphurization[J].Steelmaking, 2011, 27(2):48-51 [6]Uehara N, Fujimoto K, Hanada K, et al.Fabrication of equipments treating iron and steel slags with highly-pressurized hot water and investigation of leaching of constituents from the slags[J].TETSU TO HAGANE-JOURNAL OF THE IRON AND STEEL INSTITUTE OF JAPAN, 2014, 100(8):1014-1020 [7]何环宇，王杰奇，陈振红，等.水热浸出精炼废渣物化性能研究[J].武汉科技大学学报, 2016, 39(1):7-10 [8]He H Y, Wang J Q, Chen Z H, et al.Physicochemical properties of LF refining spent slag after hydrothermal leaching[J].Journal of Wuhan University of Science and Technology, 2016, 39(1):7-10 [9] 李慧君.NH3-(NH4)2SO4-H2O体系浸出异极矿的研究[D]. 长沙：中南大学，2009:18?28. [10]Li H J.Study on the leaching of hemimorphite in the NH3-(NH4)2SO4-H2O system[D]. Changsha: Central South University, 2009: 18?28. [11]Xiaorui Zhang, Hiroyuki Matsuura and Fumitaka Tsukihashi.Dissolution mechanism of various elements into seawater for recycling of steelmaking slag[J].ISIJ International, 2012, 52(5):928-933 [12]何环宇，王杰奇，张华，等.脱硫废渣水热浸出多组分溶解行为[J].钢铁研究学报, 2018, 30(1):26-31 [13]He H Y, Wang J Q, Zhang H, et al.Dissolution of multicomponents during hydrothermal leaching of LF desulfurization slag[J].Journal of Iron and Steel Research, 2018, 30(1):26-31 [14] 万丽，欧乐明.含油酸钠氧化锌浸出液体系的溶液化学研究[J].矿产综合利用, 2015, (2):67-70 [15]Wang L, Ou L M..Solution chemistry calculation on zinc oxide lixivium containing sodium oleate[J].Multipurpose Utilization of Mineral Resources, 2015, (2):67-70 [16] 孙会兰，涂赣峰，毕诗文，等.七铝十二钙的合成及其在高碳钠铝酸钠溶液中的溶出性能[J].轻金属, 2007, (11):17-19 [17]Sun H L, Tu G F, Bi S W, et al.Synthesization of C12A7 and it’s leaching property in sodium aluminate solution with high?Na2OC[J].Light Metals, 2007, (11):17-19 [18] F. Engstr?m, D. Adolfsson, C. Samuelsson.A study of the solubility of pure slag minerals[J].Minerals Engineering, 2013, 41:46-52 [19] 黄希祜.钢铁冶金原理，第四版[M]. 北京：冶金工业出版社，2013: 212?215. [20]Huang X H.Principles of steel metallurgy, the fourth edition[M]. Beijing: Metallurgical Industry Press, 2013: 212?215. [21]汪智勇，王敏，文寨军，等.硅酸二钙及以其为主要矿物的低钙水泥的研究进展[J].材料导报, 2016, 30(1):74-75 [22]Wang Z Y, Wang M, Wen Z J, et al.Progress on study of dicalcium silicate and low calcium cement with dicalcium silicate as a main mineral composition[J].Materials Review, 2016, 30(1):74-75 [23]张雄.介质对γ?水化的影响[J].上海建材学院学报, 1989, 2(4):323-328 [24]Zhang X.Influence of media upon the hydration of γ?C2S[J].Journal of Shanghai Institute of Building Materials, 1989, 2(4):323-328 [25]严生，蔡安兰，周际东.系统水化机理[J].硅酸盐学报, 2004, 32(4):522-523 [26]Yan S, Cai A L, Zhou J D.Hydration mechanism of C2S-C12A7-CaSO4?2H2O-H2O system[J].Journal of the Chinese Ceramic Society, 2004, 32(4):522-523
