VD炉脱氢率的影响因素及工艺优化

为了充分发挥VD炉的脱氢作用,提高生产效率,以VD炉脱氢热力学和动力学为基础,对影响脱氢率的因素进行对比分析。结果表明:钢水原始氢含量、真空度、高真空保持时间、氩气流量等是影响VD炉脱氢效果的主要因素。通过现场真空脱气工艺参数优化,VD炉的脱氢率得到提高,为生产低氢高质量品种钢创造了条件。

简述尿素二脱氢装置TH-1型催化剂的使用情况

本文介绍了泸天化尿素二装置TH-1型脱氢催化剂的选购理由、原理、工艺流程,通过对2006年至2021年脱氢反应器的运行情况及对脱氢催化剂使用情况进行分析,梳理总结出影响脱氢反应的主要原因及注意事项,为今后的工作提供参考依据、积累经验。

CO2作为RH提升气的冶金反应行为研究

钢液真空循环脱气法(RH)精炼能够利用高真空和钢液循环流动有效脱气和去除夹杂物.同时,炼钢环境下CO2可与钢液中[C]反应生成CO提高搅拌强度.因此,本文提出将CO2作为RH提升气进行真空精炼.针对CO2在RH精炼过程的冶金反应行为特性,通过热力学理论分析了极限真空条件下CO2脱碳的有利条件及限度,同时搭建了CO2作RH提升气工业试验平台,通过工业试验对比研究了CO2/Ar分别作提升气时对钢液精炼过程的影响.结果表明,若单纯考虑CO2与碳反应,则当钢液中[C]低于1.8×10-6,CO2仍然具有氧化碳元素的能力.然而,CO2对钢液中碳铝元素存在选择性氧化,当铝含量低于一定程度时,CO2主要参与脱碳反应;反之,CO2则会造成一定铝损,因此若采用新工艺需考虑铝合金加入时机以及加入量.此外,CO2用作RH提升气可获得与Ar效果相当甚至更优的脱氢效果,喷吹同等量CO2并未造成钢液的大幅温降,因此CO2完全有潜力作为RH提升气,进而完成精炼.

Clinical Analysis of 13 Cases with Burkitt Lymphoma or Burkittlike Lymphoma

OBJECTIVE To summarize the clinical characteristics and treatment effects of Burkitt lymphoma （BL） and Burkitt-like lymphoma （BLL）, and to explore the best possible optimal regimens and the treatment-related complications.METHODS Clinical data of 13 BL and BLL patients, who were pathologically diagnosed and treated in the Beijing Cancer Hospital from August 1996 to October 2008, were retrospectively analyzed, All patients received the therapeutic regimen with chemotherapy as the first-line treatment. The treatment effect and adverse reactions were evaluated.RESULTS Of the 13 patients, 12 were men and 1 was woman, with a median age of 15 years （range, 11-62）. Three of the patients were in stage Ⅰ, 2 in stage Ⅱ, 2 in stage Ⅲ, and 6 in stage Ⅳ. Advanced cases were 8 （stage Ⅲ and Ⅳ）, accounting for 61.5% of the patients. Bone marrow involvement was found in 2 cases （15.4%） and central nervous system invasion in 4 （30.8%） at the beginning of the treatment. The common involved sites included the superficial lymph nodes （61.5%）, abdominal organs （53.8%）, and abdominal and retro-peritoneal lymph nodes （38.5%）. B symptoms were observed in 7 patients （53.8%）. Serum lactate dehydrogenase （LDH） level was increased in 8 of the 10 patients who underwent the serum LDH determination, while serum uric acid level was increased in 1 of the 10. Pathological diagnosis showed that 11 of the cases were BL and 2 BLL. Of the 13 patients, 11 （84.6%） achieved a complete remission （CR） or CR/unconfirmed （CRu）, and 1 （7.7%） a partial remission （PR）, with a total responsive rate of 92.3%. At a median follow-up of 8 months （range 5-35）, 6 patients were found dead at the end of the follow-up. One of the 13 patients was lost to the follow-up. The 1-year overall survival, progression-free survival and disease-free survival rates were 56.98%, 32.31% and 39.77%, respectively. The grade-Ⅲ or Ⅳ myelosuppression was found in 9 patients during the chemotherapy （69.2%）, and tumor lysis syndrome and grade- Ⅳ total gastrointestinal mucositis were seen in 1.CONCLUSION Intensive short-course chemotherapy is recommended as the optimal first-line treatment for BL and BLL, and actively preventive treatments for chemotherapy-related adverse reactions are essential in the treatment course.

RH真空精炼装置性能优化研究

针对某厂RH精炼工序提升钢产品质量过程存在的问题进行研究分析,提出了合理的装置性能优化方案。对全套四级真空泵(B1 B2 S3 S4)更新迭代;优化真空料仓结构解决密封和称量精度问题;环流气体阀站升级优化提升了钢液循环效率;蒸汽减温减压装置更新稳定了真空泵的工作气源条件。优化后效果如下:真空度为67 Pa时,真空抽气能力提升150 kg/h,真空度到100 Pa的平均时间为2.3 min,真空稳定性提升(真空度反弹值在100 Pa以下);钢液终点氢含量小于0.00012%的比例较优化前提高36.40%,浸渍管在线使用增加30炉次,高牌号道岔轨、高速轨及重轨系列产品的总产量增加10.79%。优化改造后,RH精炼装置性能显著提升,对真空精炼装备的优化升级具有指导和借鉴意义。