鄂尔多斯盆地靖边地区马家沟组气田水地球化学特征及锂来源

鄂尔多斯盆地靖边地区马家沟组气田水中Li+浓度较高,部分井区达到工业品位,勘探开发潜力巨大,但锂来源尚不明确。以靖边地区马家沟组气田水为研究对象,采用薄片鉴定、X射线衍射分析、微量元素分析及Sr、Li同位素分析等方法,对马家沟组气田水地球化学特征进行了研究,并讨论了水体中锂来源。结果表明:①气田水中离子浓度变化极大,矿化度为0.12~228.19 g·L^(-1),平均值为39.87 g·L^(-1),部分水体达到卤水范畴,气田水pH值为4.82~8.44,以弱酸性为主,水化学类型以CaCl_(2)型为主,部分井区为MgCl_(2)型或NaHCO_(3)型;②气田水钠氯系数普遍大于0.87,脱硫系数普遍小于1,变质系数普遍大于0,氯镁系数主要为20~90,储层整体封闭性好,水体还原性强,变质程度高,属于高变质、高浓缩的水体,部分井区储层封闭条件被破坏,受大气水影响明显;③气田水Li同位素具有早奥陶世海水的特征,Sr同位素受到凝灰质组分及大气水岩溶的影响,^(87)Sr/^(86)Sr值高于马家沟组沉积时期正常海水;④马家沟组含凝灰质组分的岩石和岩溶角砾岩填隙物普遍具有较高的Li^(+)浓度,Li同位素特征指示气田水中锂主要来自马家沟组地层,马家沟组富锂气田水是加里东期马家沟组地下岩溶水埋藏和演化的结果。

复吹转炉渣金间传质物理模拟及应用

将200t复吹转炉按照1∶12的比例缩小,用液体石蜡模拟炉渣、水模拟钢水、压缩空气模拟顶吹和底吹气体,在实验室建立模拟复吹转炉吹炼过程熔池渣金间传质的试验模型,在顶吹气体流量为88m^(3)/h条件下,通过相对集中非对称布置的4、6、8、10、12支底枪吹入不同底吹气体,用苯甲酸作为传输物质,试验测定了复吹转炉熔池渣金间的容量传质系数,考察不同底枪支数和布置以及底吹气体流量对渣金间传质速率的影响,优化复吹转炉底枪布置和底吹气体流量,以增强复吹转炉熔池的搅拌,改善熔池渣金反应动力学条件。研究结果表明,当底吹气体流量为1.14m^(3)/h时,在4~12支的底枪布置方案中,4、6支底枪布置方案的容量传质系数(分别为1.77×10^(-4)、1.80×10^(-4)L/s)低于8、10、12支底枪布置方案的容量传质系数(分别为2.41×10^(-4)、2.24×10^(-4)、2.42×10^(-4)L/s);当底吹气体流量为0.57m^(3)/h时,在8~12支底枪布置方案中,10、12支底枪布置方案的容量传质系数(分别为1.68×10^(-4)、1.69×10^(-4)L/s)明显大于8支底枪布置方案的容量传质系数(0.95×10^(-4)L/s);在底吹气体流量不小于1.14m^(3)/h后,8、10、12支底枪布置的容量传质系数相差不大,在2.24×10^(-4)~2.87×10^(-4)L/s的范围;在气体流量小于1.14m^(3)/h时,随着底吹气体流量的增加,渣金间的容量传质系数增加显著,底吹气体流量大于1.14 m^(3)/h后,容量传质系数增加变缓。将12支底枪布置方案应用到实际复吹转炉,整个炉役的平均碳氧积为0.00196×10^(-4),在不同炉龄阶段,终点钢水平均碳氧积为0.00188×10^(-4)~0.00204×10^(-4),终点钢水碳氧积小于0.0025×10^(-4)的炉次比例达到90.53%。

Flow Control in Six-Strand Billet Continuous Casting Tundish With Different Configurations

A 1∶2.5 scale tundish model was set up in laboratory for a six-strand billet continuous casting tundish with different configurations to investigate fluid flow characteristics under different operational conditions by measuring residence time distribution curves.It was found that minimum residence time,maximum concentration time and average residence time of the three strands on the same side of the tundish with the former configuration under normal operation,that is,six strands were open,were small and non-uniform and the tundish had large dead volume fraction.Vortexes easily formed on the liquid surface in the pouring zone of the tundish.The fluid flow characteristics in the tundish with the optimal turbulence inhibitor and baffles were improved and became less non-uniform among the strands.Vortexes were not found on the pouring zone surface in the optimal tundish.For non-normal operation,that is,one strand was close,it was important to choose which strand to be closed for maintaining flow characteristics of the rest two strands.It was found from this investigation that fluid flow characteristics in the optimal configuration tundish with closing strand 2 were better than those with closing strand 3 on the same side.