Manganese migration behavior in the RH vacuum process of manganese-containing steel
-
摘要: Ruhrstahl Heraeus（RH）精煉爐是重要的二次精煉裝備，但在真空處理過程中會遇到鋼液易揮發合金元素的損失量大的問題，且造成鋼液真空噴濺的結瘤及對后續鋼液的二次氧化。針對含錳鋼RH真空處理過程錳的氣化導致的元素損失及真空噴濺等問題，跟蹤和研究了120 t RH不同真空處理模式下鋼液中Mn元素的變化規律及遷移行為。分析了錳元素損失與其揮發和真空噴濺的關系，并在RH真空室內壁不同位置結瘤物的解剖實驗中得到驗證。研究表明，鋼液中Mn元素在RH真空過程中存在著明顯損失，真空前期損失量最大；RH真空室內壁結瘤物中錳氧化物的質量分數整體占比高達14%～70%；熱力學計算結果顯示：溫度、鋼中Mn的含量以及真空度對Mn的揮發行為均有著很大的影響，是真空過程錳遷移的關鍵影響因素。通過改進真空壓降模式，采用步進式抽真空，元素錳的損失由原先的2×10?4降低至1×10?4，結果對現場生產具有很強的指導意義，通過改進真空壓降模式可以有效的抑制鋼液的噴濺和揮發，進而減少合金元素錳的損失。Abstract: The Ruhrstahl Heraeus (RH) refining furnace is a piece of important secondary refining equipment that is widely used in the production of special steel owing to its high efficiency of degassing, decarburization, and de-intercalation. However, molten steel that has a high alloy content will encounter key problems in the vacuum treatment process, and the loss of volatile alloying elements in the molten steel is considerable, resulting in the nodulation of the molten steel vacuum splashing and secondary oxidation of the subsequent molten steel. To address the problems of elemental loss and vacuum splashing caused by manganese (Mn) gasification during the vacuum processing of manganese-containing steel using RH, the variation and migration behavior of Mn in molten steel under different vacuum treatment conditions of 120 t RH were examined. This study analyzed the relationship between manganese elemental loss and its volatilization and vacuum splattering, and it was verified in an anatomical experiment of the nodule at different positions inside the RH vacuum chamber. The results show that elemental Mn in the molten steel shows obvious loss during the vacuum process of RH, and the loss in the early stage of the vacuum process is the largest. The composition of manganese oxide in the nodule of the RH vacuum chamber is as high as 14%–70%, and the thermodynamic calculation results show that temperature, the content of Mn in the steel, and the degree of vacuum have a considerable influence on the volatilization behavior of Mn, which is the key influencing factor for manganese migration during the vacuum process. By improving the vacuum pressure drop mode, a stepwise vacuum is used to reduce the loss of elemental Mn from the original 2×10?4 to 1×10?4. The results have considerable significance for on-site production, and steel can be effectively restrained by improving the vacuum pressure drop mode. Additionally, the splashing and volatilization of liquid reduces the loss of the alloying element Mn.
-
Key words:
- RH vacuum treatment /
- Mn gasification /
- splash /
- nodulation /
- step vacuum
-
圖 2 RH過程中鋼中[Mn]質量分數變化規律
Figure 2. Change law of [Mn] content in steel during the RH process
圖 3 RH過程中密集取樣Mn含量的變化
Figure 3. Variation of Mn content in intensive sampling during RH
圖 4 RH真空處理過程中煙氣量變化. （a, b, c）預抽真空過程煙氣量的變化；（d）真空處理階段煙氣的情況
Figure 4. Flue change during the RH vacuum process: (a, b, c) the changes of flue gas volume during pre-evacuation; (d) the condition of the flue gas in the vacuum processing stage
圖 5 不同進站[Mn]含量RH過程中質量分數損失量
Figure 5. Attenuation of Mn content in different RH stations during RH
圖 6 對比實驗RH過程中[Mn]質量分數含量變化
Figure 6. Comparison of [Mn] contents in the experimental RH process
圖 7 RH真空槽體結瘤物宏觀示意圖（a），RH內部結瘤物掃描電鏡照片及相應的面掃描結果（b, c, d）、(e, f, g)、(h, i, j)
Figure 7. Macroscopic diagram of the RH vacuum tank nodule (a), RH internal nodule SEM and mapping results (b, c, d), (e, f, g), (h, i, j)
圖 10 不同溫度和成分下，鋼液中錳合金元素平衡蒸氣壓變化圖（a），在1873 K下，錳的揮發量與真空度的變化關系圖（b），在1873 K下，錳合金元素蒸氣壓與摩爾分數變化關系圖（c），在X[Mn] = 0.0078時，錳合金元素蒸氣壓與溫度變化關系圖（d）
Figure 10. Variation (a) of the equilibrium vapor pressure of Mn alloy in molten steel for different temperatures and compositions, relationship (b) between the amount of Mn volatilization and the degree of vacuum at 1873 K, relationship (c) between vapor pressure and molar fraction of manganese alloy elements at 1873 K, relationship (d) between vapor pressure of manganese alloy element and temperature change at X[Mn]=0.0078
圖 11 RH內部Mn的遷移機理圖. （a）鋼-渣擴散過程；（b）RH內部揮發傳質過程；（c）RH真空室內壁中部激冷凝固；（d）RH頂部由于物理抬升附著內壁
Figure 11. Schematic diagram of the migration mechanism of Mn in RH: (a) Steel slag diffusion process; (b) RH internal volatilization and mass transfer process; (c) RH vacuum chamber condensed and solidified in the middle of the wall; (d) RH top attached to the inner wall due to physical lifting
表 1 實驗鋼種A化學成分（質量分數）
Table 1. Chemical compositions of the target steel grades A
% C Si Mn P S Als 0.48～0.51 0.26～0.30 0.60～0.90 <0.020 <0.015 0.020～0.030 
下載: 導出CSV
表 2 實驗鋼廠120 t RH主要技術參數
Table 2. Main technical parameters of 120 t RH in the experimental steel plant
Parameter Value Parameter Value Height inside the vacuum chamber/mm 9910 Length of dipping tube/mm 975 Inside diameter of vacuum chamber/mm 1744 The flow of increase gas（Standard state）/(L·min?1) Max.120 Inside diameter of dipping tube/mm 500 Centerline distance of dipping tube/mm 1244 Number of argon supply nozzles 10 Ultimate vacuum/Pa ≤28 Suction capacity of vacuum pump/(kg·h?1) 500~2800
下載: 導出CSV
表 3 取樣方案
Table 3. Sampling plan
Plan number The outbound
of LFThe arrival
of RHTime after vacuum ≤100 Pa The broken
of RHTime after soft blowing The outbound
of RH0 min 5 min 10 min 15 min 5 min 10 min 15 min Option one ― Sample 1 ― ― ― ― Sample 2 ― ― ― Sample 3 Option two Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 Sample 7 Sample 8 Sample 9 Sample 10 Sample 11
下載: 導出CSV
表 4 RH結瘤物中各部位質量分數占比
Table 4. Composition of each part in the nodule of RH
Ingredient Mass fractions at different sampling locations/% Outlet of hot bend Entrance to the hot bend Top of upper tank Middle of upper tank Lower of upper tank Upper part of lower tank Fe2O3 53.727 13.678 38.985 67.179 76.192 78.994 MnO 35.783 70.401 50.397 24.665 14.266 14.190 MgO 3.676 7.463 4.050 2.905 4.135 2.331 SiO2 3.532 1.207 2.576 2.093 2.093 2.042 SO3 0.663 0.859 0.928 0.752 0.752 0.873 CaO 1.418 ― 1.291 0.928 0.928 0.767 Cr2O3 0.452 0.416 0.851 1.214 1.214 0.614 Al2O3 ― ― 0.771 ― 0.425 ―
下載: 導出CSV
表 5 不同溫度時各種金屬元素的平衡蒸氣壓
Table 5. Equilibrium vapor pressure of various metal elements at different temperatures
Temperature/K Equilibrium vapor pressure of Si/Pa Equilibrium vapor pressure of Fe/Pa Equilibrium vapor pressure of Mn/Pa 1673 0.04 033 893 1733 0.10 0.81 1604 1793 0.26 1.86 2760
下載: 導出CSV
259luxu-164<th id="5nh9l"></th> <strike id="5nh9l"></strike> <th id="5nh9l"><noframes id="5nh9l"><th id="5nh9l"></th> <strike id="5nh9l"></strike> <th id="5nh9l"><noframes id="5nh9l"> <th id="5nh9l"></th> <strike id="5nh9l"><noframes id="5nh9l"><span id="5nh9l"></span> <span id="5nh9l"><noframes id="5nh9l"><span id="5nh9l"></span> <strike id="5nh9l"><noframes id="5nh9l"><strike id="5nh9l"></strike> <span id="5nh9l"><noframes id="5nh9l"> <span id="5nh9l"><noframes id="5nh9l"> <span id="5nh9l"></span> <span id="5nh9l"><video id="5nh9l"></video></span> <th id="5nh9l"><noframes id="5nh9l"><th id="5nh9l"></th> -
參考文獻
[1] Li Y H, Bao Y P, Wang M, et al. Influence of process conditions during Ruhrstahl-Hereaeus refining process and effect of vacuum degassing on carbon removal to ultra-low levels. Ironmaking Steelmaking, 2015, 42(5): 366 doi: 10.1179/1743281214Y.0000000236 [2] Zhao L H, Guo J L, Xu J L, et al. Complex bubble formation in the vacuum chamber and the up leg of the Rheinsahl-Heraeus. Chin J Eng, 2018, 40(4): 453趙立華, 郭建龍, 徐佳亮, 等. RH真空室內氣泡行為的研究. 工程科學學報, 2018, 40(4):453 [3] Li Y J, Gao H C, Wu Y G, et al. Optimization of secondary refining process for ultra-low carbon steel. Steelmaking, 2010, 26(5): 11李應江, 高海潮, 吳耀光, 等. 超低碳鋼爐外精煉工藝的優化. 煉鋼, 2010, 26(5):11 [4] Yoshioka T, Nakahata K, Kawamura T, et al. Factors to determine inclusion compositions in molten steel during the secondary refining process of case-hardening steel. ISIJ Int, 2016, 56(11): 1973 doi: 10.2355/isijinternational.ISIJINT-2016-324 [5] Wang M, Bao Y P, Zhao L H, et al. Difference analysis in steel cleanness between two RH treatment modes for SPHC grade. ISIJ Int, 2015, 55(8): 1652 doi: 10.2355/isijinternational.ISIJINT-2015-027 [6] Lei H, Yang S X, Huang D H. The control of decarburization process spitting is optimize // Proceedings of the 15th Steelmaking Academic Conference. Xiamen, 2008: 276雷輝, 楊森祥, 黃登華. RH脫碳過程噴濺控制的工藝優化// 第十五屆全國煉鋼學術會議文集. 廈門, 2008:276 [7] Wu Q M. The control of splashing in decarburization process of RH furnace. Vacuum, 2012, 49(5): 21 doi: 10.3969/j.issn.1002-0322.2012.05.006吳全明. RH真空爐脫碳過程噴濺的控制. 真空, 2012, 49(5):21 doi: 10.3969/j.issn.1002-0322.2012.05.006 [8] Zhan W L, Wu K, Fu P, et al. Establishment and application of the Rist operating line for the COREX melter gasifier. J Univ Sci Technol Beijing, 2013, 35(4): 448湛文龍, 吳鏗, 付平, 等. COREX熔融氣化爐Rist操作線的建立和應用. 北京科技大學學報, 2013, 35(4):448 [9] Yu Y G, Chen B P, Wang Y G, et al. Evaporation dynamics of trace elements during vacuum induction melting of steel. J Univ Sci Technol Beijing, 1993, 15(6): 549于月光, 陳伯平, 王玉剛, 等. 鋼真空感應熔煉過程痕量元素揮發的動力學. 北京科技大學學報, 1993, 15(6):549 [10] Zhang Y L, Fu Z H, Li S Q, et al. Comparative analysis on the vaporization behavior of zinc and lead in molten slag system. J Univ Sci Technol Beijing, 2007, 29(Suppl 2): 73張延玲, 付中華, 李士琦, 等. 熔渣中Zn、Pb揮發行為的對比分析. 北京科技大學學報, 2007, 29(增刊2): 73 [11] Yu Y G, Chen B P, Wang Y G, et al. Evaporation of trace bismuth during vacuum melting of steel. J Univ Sci Technol Beijing, 1994, 16(6): 522于月光, 陳伯平, 王玉剛, 等. 真空感應熔煉過程中微量Bi的揮發. 北京科技大學學報, 1994, 16(6):522 [12] Kong L Z, Deng Z Y, Zhu M Y. Vaporization behaviors of manganese in medium and high Mn steel grades during vacuum treatment. Special Steel, 2018, 39(4): 17 doi: 10.3969/j.issn.1003-8620.2018.04.005孔令種, 鄧志銀, 朱苗勇. 中高錳鋼在真空精煉過程中的氣化行為. 特殊鋼, 2018, 39(4):17 doi: 10.3969/j.issn.1003-8620.2018.04.005 [13] Zhao Y P, Zhang J Z. Study on the evaporation of molten ferromanganese at high temperature. Ferro-alloys, 2002, 33(4): 18 doi: 10.3969/j.issn.1001-1943.2002.04.006趙躍萍, 張金柱. 熔融錳鐵高溫揮發的實驗研究. 鐵合金, 2002, 33(4):18 doi: 10.3969/j.issn.1001-1943.2002.04.006 [14] Geng D Q, Lei H, He J C. Effect of traveling magnetic field on flow, mixing, decarburization and inclusion removal during RH refining process. ISIJ Int, 2012, 52(6): 1036 doi: 10.2355/isijinternational.52.1036 [15] Wu J, Ren T. The technique of circumfluence control for molten steel in RH. Heavy Machinery, 2005(3): 4 doi: 10.3969/j.issn.1001-196X.2005.03.002吳杰, 任彤. RH鋼水環流控制技術. 重型機械, 2005(3):4 doi: 10.3969/j.issn.1001-196X.2005.03.002 [16] Wang S J, Dong Y C. Thermodynamic properties of phosphorus and manganese in ferromanganese melts. J Iron Steel Res, 1996, 8(2): 1王世俊, 董元箎. 錳鐵熔體中磷和錳的熱力學性質. 鋼鐵研究學報, 1996, 8(2):1 [17] Ryan H F, Suiter J. Further comments on stacking faults in tungsten. J Less Common Met, 1966, 10(5): 371 -
點擊查看大圖
計量
- 文章訪問數: 1523
- HTML全文瀏覽量: 1119
- PDF下載量: 72
- 被引次數: 0
