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1.
以转底炉技术利用钛资源的基础研究   总被引:5,自引:1,他引:5  
提出了一种以转底炉煤基直接还原技术利用钛资源的新工艺及两个不同的方案。该工艺以攀枝花钒钛磁铁精矿或钛精矿粉、煤粉和少量添加剂组成的复合球团为原料,在高温加热条件下将含钛矿中的氧化铁还原为铁,经渣铁分离后获得生铁和富集了的钛渣。第一方案以钒钛磁铁精矿配20%钛精矿为原料,还原后渣铁自然分离,得到块铁和品位为50%左右的钛渣;第二方案以钛精矿为原料,还原后经破碎磁选分离得到粒铁和TiO2富集率为~75%的钛渣。对这两种方案均进行了初步试验,确定了合理的工艺条件。  相似文献   

2.
为了实现钒钛磁铁精矿的低温综合利用,采取碳热钠化工艺降低还原和熔分温度,考察了铁、钒、钛的富集回收情况。结果表明,钠化剂显著改善了钒钛磁铁精矿的还原及熔分效果,当钠化比为1.2时,1 100℃还原60 min即可达到90%以上的金属化率,1 250℃以上的温度下熔分后,铁的收得率达到96%,钒在铁水中的富集率为75%。熔分渣在无酸环境下经湿法处理后TiO_2含量达到77%,经还原熔分去除铁后品位可进一步提升。  相似文献   

3.
以焦粉为还原剂,开展了氧化钛精矿含碳球团等温碳热还原试验研究,采用积分法进行了碳热还原动力学分析,还原温度分别为1 000、1 100、1 200、1 300℃。氧化钛精矿中铁氧化物还原度随还原温度和时间增加而增加,还原度可达91%。氧化钛精矿在1 000~1 300℃固相还原前期(60 min)受界面化学反应控制,反应活化能为51.23 k J/mol;反应后期(60 min)受扩散控制,反应活化能为93.53 k J/mol。氧化钛精矿碳热还原过程物相转变历程为:Fe2Ti O5→Fe3Ti3O10→Fe Ti O3,物相转变过程增加颗粒内部空隙,增加还原比表面积,改善还原过程气体扩散条件,加快还原初期化学反应速率。  相似文献   

4.
以钛精矿和石墨为原料,在氮气气氛下通过碳热还原法制备出碳氮化钛(Ti CN)粉体。结合XRD、SEM、化学成分分析和TG-DSG综合热分析研究了配碳量及反应温度对钛精矿碳热还原进程的影响。研究结果表明,配碳量的增加影响逐级还原反应温度以及反应总失重,当配碳量达到23%时碳氮化钛产物中出现游离碳。钛精矿碳热还原过程中铁氧化物优先还原,钛氧化物经逐级还原形成Ti CN,还原顺序为Ti O2→Ti4O7→Ti3O5→Ti N→Ti(C,N,O)→Ti CN。得到的碳氮化钛粉体呈微米级不规则形状。  相似文献   

5.
对钒钛磁铁精矿预还原球团熔融还原冶炼中添加剂的影响进行了研究,并对渣型制度进行了优化。熔融还原渣碱度、添加剂氧化镁和氧化铝对钒钛磁铁精矿的熔融还原作用明显。在添加剂作用下,1 500℃电炉冶炼10min后的熔融还原产物为含96.9%铁、0.52%钒的生铁,以及含66.13%TiO_2的熔融还原渣,实现了钒钛磁铁精矿冶炼中铁钒和钛的有效分离。  相似文献   

6.
在1 000~1 300℃添加少量Na_2CO_3+NaCl复配添加剂,以无烟煤做还原剂等温还原低品位钒钛磁铁精矿,再通过磁选分离获得铁精粉和钒钛渣。考察了C/Fe摩尔比、还原温度和还原时间对铁的还原、钒钛迁移富集行为以及物相转化规律的影响。结果表明,C/Fe摩尔比和反应温度对直接还原过程中有价组分迁移富集的影响很大,当C/Fe摩尔比为1.2时,在1 200℃还原2h,钒钛磁铁矿精矿的金属化率可达到92.8%,还原后钒主要富集在钛渣相中,有效实现了铁与钒/钛的分离。  相似文献   

7.
试验中研究了钒钛烧结矿的高温冶金性能。试验结果指出,在一定范围内,提高碱度和增加烧结矿中MgO含量来改善钒钛烧结矿高温还原性能及软熔性能是有效的。增加MgO还可抑制硅、钛的还原及碳氮化物的生成,有利于渣铁熔融分离而滴落。钒钛磁铁精矿配入普通富矿粉及适当增加烧结混合料配碳量,可以降低炉渣中TiO_2的活度,增加炉渣的氧化能力,有利渣铁分离。但不利于烧结矿的高温还原性和软熔性能的改善。  相似文献   

8.
国内外新闻     
《钛工业进展》2013,(2):6+20+45-47
攀钢钒钛矿高效分离课题通过国家科技部验收由攀钢牵头承担的"十一五"国家科技支撑计划课题---"攀枝花钒钛磁铁矿高效分离与资源综合利用技术开发"课题,2月27日在北京顺利通过国家科技部验收。该课题由中国有色金属工业协会组织,攀钢牵头,北京科技大学、北京大学参加。通过实验研究、工业试验和装备研发,攀钢建成了具有完全自主知识产权的"攀钢100 kt/a钒钛资源综合利用新工艺中试线",解决了钒钛磁铁矿直接还原温度高、易粘接、转底炉布料出料不均匀及出料设备寿命短、热金属化球团氧化粘结料罐、冶炼钒钛金属化球团时钒还原率低及渣铁难分离、高镁铝低品位含钛炉渣提钛等诸多技术难题,铁、钒、钛从精矿至半钢、片  相似文献   

9.
采用热重、XRD,SEM等技术检测CO还原钛精矿的失重率、物相转变及显微结构。结果表明,预氧化钛精矿还原度随还原温度和时间增加而增加,在1150℃还原270min后还原度达到87.97%。还原产物的主要组成为金属铁、FeTi_2O_5和少量的TiO_2。  相似文献   

10.
用磁选的方法从含钛高炉渣中回收碳氮化钛   总被引:1,自引:0,他引:1  
采用冶炼钒钛磁铁矿产生的含TiO2 20%~26%的高炉渣为原料,通过对渣中的钛氧化物进行还原碳化和氮化处理生成碳氮化钛后,利用铁作为载体,用磁选的方法实现碳氮化钛和脉石矿物的分离.磁选后获得Ti(C,N)品位大于36.46%,回收率达到43.77%的碳氮化钛精矿.  相似文献   

11.
转炉炉壳热应力分析   总被引:5,自引:1,他引:4  
任学平  郭志强  邹家祥 《炼钢》2001,17(6):47-49
根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。  相似文献   

12.
Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.  相似文献   

17.
通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。  相似文献   

18.
Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.  相似文献   

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Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.  相似文献   

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