资源描述
熔渣对镁碳耐火材料的腐蚀增加碳含量的影响 THE INFLUENCE OF CARBON CONTENT ON THECORROSION OF MGO-C REFRACTORY MATERIALCAUSED BY ACID AND ALKALINE LADLE SLAG This paper describes an investigation of the influence of increasing carbon content on the corrosion of MgO-C refractory material by molten slag. The refractory material contained mass fraction of 98 % MgO, approximately 2 % Fe2O3, and graded quantities from 3 % to 18 % C. The corrosion was investigated in melts of reduction ladle slags at a temperature of 1600 C in laboratory conditions. A sample of refractory material with dimensions of 10 10 100 mm was submerged into the molten slag and exposed to the corrosive effect of the slag for 60 min. After the expose of the refractory material the slag was cooled down and submitted to a chemical analysis. After a comparison of the MgO content in the slag before and after the corrosion test the amount of MgO content in the melt was determined and the degree of corrosion of the refractory material was quantified. The experiments were realised using final slags from the ladle furnace (LF), strongly alkaline slag w(CaO)/w(SiO2) = 4.43, and also acidic slags w(CaO)/w(SiO2) = 0.94 with different contents of CaF2. The work was carried out within the frame of the projects EUREKA E!3580 and IMPULS FI-IM4/110. RESULTSThe chemical composition of the slags before the exposure is given in the Table 1.Table 1 shows that the acidic slag contains very little of the CaF2 (w = 0.82 %), and that the alkaline slag contains 7.18 % CaF2, added to increase its fluidity. Table 1: Chemical composition and alkalinity of the slags used for the corrosion testTabela 1: Kemina sestava in bazinost linder, ki sta bili uporabljeni za preizkuse korozijeThe MgO content of the slags after exposure to the refractory material is shown in Tables 2 and 3. The tables also contain increments of the MgO content and the increments related to the initial MgO content in the slags (MgO). The six tested samples of refractory material differed only in terms of the carbon content, graded from 3 % to 18 %. However, sample 5 % contained 15 % C in addition to an antioxidant. Table 2: Changes to the MgO content in an acidic slag for different carbon contents in the refractory materialTabela 2: Spremembe vsebnosti MgO v kisli lindri pri razlini vsebnosti ogljika v ognjevzdrnem materialuTable 3: Changes to the MgO contents in an alkaline slag for different carbon contents in the refractory materialTabela 3: Spremembe vsebnosti MgO v bazini lindri pri razlini vsebnosti ogljika v ognjevzdrnem materialuFigures 1 and 2 show the change of the MgO content in slags with respect to the carbon content in the refractory material.Figure 1: Change in the content of MgO in acidic slag with respect to the carbon content in the refractory materialSlika 1: Spremembe vsebnosti MgO v kisli lindri v odvisnosti od vsebnosti ogljika v ognjevzdrnem materialuFigure 2: Change in the content of MgO in the alkaline slag with respect to the carbon content in the refractory materialSlika 2: Spremembe vsebnosti MgP v bazini lindri v odvisnosti od vsebnosti ogljika v ognjevzdrnem materialu In order to enable a comparison of the quantitative effect of carbon content in the MgO-C refractory material on its corrosion intensity by acidic and alkaline slag, the changes in the MgO and carbon contents in Tables 1 and 2 were transformed according to Equations (1) and (2). (1)(2)where: is the transformed form of the independent variable of the quantity lg w(C), 1 is the transformed form of the dependent variable of the quantity lg w(MgO), 1 xi is the concrete value of the independent variable of the quantity lg w(C), 1 yi is the concrete value of the dependent variable of the quantity lg w(MgO), 1 X max; xmin, ymax; ymin are the maximum or minimum values of the variable quantities lg w(C) and lg w(MgO), 1 The quantities thus transformed were analysed with linear regression and the equations of the straight lines, shown in Figures 3 and 4, were obtained.Figure 3: Dependence of w (MgO) in the acidic slag on the carbon contents in refractory material after linear regression of the experimental dataSlika 3: Odvisnost MgO v kisli lindri pri razlini vsebnosti ogljika v ognjevzdrnem materialu, linearna regresija eksperimentalnih rezultatovFigure 4: Dependence of w(MgO) in the alkaline slag on the carboncontents in refractory material evaluated by linear regression of the experimental dataSlika 4: Odvisnost MgO v bazini lindri pri razlini vsebnosti ogljika v ognjevzdrnem materialu, linearna regresija eksperimentalnih rezultatov Figures 3 and 4 indicate that the similarities of the dependencies expressed by the correlation coefficient are, in both cases, close, and the value of P is even lower than 0.05. The value P indicates the statistical significance of the tested factor. A value of P 0.05 means that the tested factor has a statistically significant impact on the values of the given parameter. The effect of increasing the carbon content on reducing the wear of the MgO-C refractory material is significant for both types of slags this is clearly evident from the slope of the straight line and the corresponding angle,which approaches 45. For the acidic slag the scatter of the values is smaller and the slope of the dependence is greater.CONCLUSIONS The acidic slag (B1 = 0.94) dissolves a great deal more MgO-C refractory material, i.e., within the range 4.111.8 % MgO. The relative change of the MgO content in the slag is in the range= 51.2147.5 %. The alkaline slag (B1 = 4.43) dissolves significantly less MgO-C refractory material, i.e., within the range 0.64.1 % MgO, and the relative change of the MgO content is= 10.773.2 %The favourable effect of carbon in MgO-C refractory material on delaying the corrosion is stronger, particularly above 10 % C, for both slags, but more in the acidic slags with low contents of easily reducible oxides. The dependence w(MgO) = f(w(C) is hyperbolic and shows a good correlation with the experimental data. The possible effect of an antioxidant was not detected, probably because the tests were performed with reduction ladle slags. 碱性钢包渣对MgO-C耐火的酸腐蚀造成了物质中碳含量的影响 本文介绍了熔渣对镁碳耐火材料的腐蚀增加碳含量的影响进行调查。耐火材料中98的MgO的质量分数,约2的氧化铁,并从3到18C.腐蚀,减少钢包渣熔体调查在1600在实验室条件下的温度梯度的数量。10 *10 *100毫米的尺寸耐火材料的样本浸入熔渣和暴露60分钟到渣的腐蚀作用。耐火材料暴露后的渣冷却下来,并提交到化学分析。腐蚀试验后的炉渣中MgO含量比较前后熔体中MgO含量的金额确定和耐火材料的腐蚀程度量化。实验实现了使用最后的炉渣,钢包炉(LF),强碱性渣W(氧化钙)/ W(二氧化硅)= 4.43,酸性炉渣W(氧化钙)/ W(SiO2)的= 0.94氟化钙含量不同。EUREKA E!3580和FI-IM4/110 IMPULS项目的框架内开展工作。 耐火材料暴露后各化学成分含量在表1。表1显示酸性渣中含有极少量的氟化钙(=0.82%),而且碱性渣中含有7.18% 氟化钙,增加其流动性增加。耐火材料暴露后炉渣中氧化镁含量如表2和表3。该表还包含氧化镁含量的增量和增量与最初的氧化镁含量的炉渣(镁)。六个测试样品的耐火材料只有在不同的碳含量,等级从3%到18%。然而,样本5%载15%除了抗氧化剂。图1和图2显示变化的氧化镁渣中相对于碳含量的耐火材料。为了使比较的定量影响碳含量镁碳耐火材料的腐蚀强度的酸性和碱性渣,变化的氧化镁和碳含量在表1和表2转化根据方程(1)和(2)。 (1)(2)其中:是独立变量的转化形式的数量 是变量的转化形式的数量Xi是独立变量的具体值的数量 Yi是变量的具体值的数量X max; xmin, ymax; ymin 是变量的最大值或最小值通过对数据的分析,获得了线性回归方程的直线,显示在图3、4 图三 图四图三和图四表面,相似依赖性的相关系数,在这两种情况下,关闭,和价值的更是低于0.05。该值表示测试的因素的统计意义。值0.05,测试的因素对统计值的给定参数有重大影响。影响碳含量增加对减少磨损镁碳砖耐火材料是重要的两种渣这45方法,显然是直线的斜率和相应的角度,在酸性渣分散的值较小,斜坡的依赖性更大结论酸性渣(B1 = 0.94)溶解大量镁碳耐火材料,例如,范围内的4.111.8%氧化镁。相对变化的氧化镁含量的炉渣的范围是51.2=147.5%。碱性渣(B1 = 4.43)溶解大大低于镁碳耐火材料,例如,范围内的0.64.1%氧化镁,和相对变化的氧化镁含量=10.773.2%有利的影响,碳镁碳耐火材料延缓腐蚀性较强,特别是10%以上,但在酸性渣的含量较低,容易还原氧化物。w(MgO) = f(w(C)是双曲线,显示良好的相关性的实验数据。抗氧化剂的作用可能并没有发现,可能是因为进行了钢包渣测试少。
展开阅读全文