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1.
系统分析了安钢炼铁生产中几种常用炉料的高温冶金性能,结果表明,安钢自产高碱度烧结矿具有较好的还原性,但其低温还原粉化率却是最高的;酸性球团矿及块矿则有着较好的低温还原粉化指数及良好的熔滴性能,能够与高碱度烧结矿搭配形成合理的综合炉料结构,满足高炉冶炼要求。  相似文献   

2.
对武钢目前使用的不同炉料的冶金性能进行了研究,结果表明,武钢自产烧结矿铁分较稳定,低温还原粉化指标稍差,还原度却较好;块矿及球团矿低温还原粉化指标较好,还原度稍差;高碱度烧结矿的滴落温度明显高于酸性球团矿,而酸性球团矿的软化区间较高碱度烧结矿要窄。结合现场生产实际,合理的炉料结构为烧结矿65%、球团矿28%、块矿7%。  相似文献   

3.
对安钢常用几种原料的冶金性能进行了分析,结果表明,孔隙率发达的高碱度烧结矿的还原度最高,其次是印度块矿和海南块矿,澳矿和南非块矿的还原度最低,但澳矿和南非块矿的低温还原粉化指数最低,高碱度烧结矿和澳矿及南非块矿的软化开始温度、矿石熔滴温度较高,但其矿石软化温度区间、矿石软熔温度区间均比加拿大球团和海南块矿要宽,澳矿和南非块矿的最大压差最小,综合炉料具有较好的冶金性能.  相似文献   

4.
针对南钢低硅烧结矿低温还原粉化性能差的情况,研究了碱度与低硅烧结矿低温还原粉化性能之间的关系.结果发现,烧结矿中集中分布的赤铁矿、骸晶赤铁矿及孔洞是导致其低温还原粉化性能恶化的重要原因,要降低还原粉化率,应着重改善其微观结构.在南钢原料条件下,将碱度提高到2.3时,烧结矿微观结构得到改善,还原粉化性能提高.  相似文献   

5.
对鄂州球团矿的冶金性能进行试验研究,并通过高温熔滴试验探讨了鄂州球团矿合理的配矿范围.研究结果表明,鄂州球团矿具有较好的低温还原粉化性能和良好的熔滴性能,能够与高碱度烧结矿、天然块矿搭配,构成合理的炉料结构,满足高炉冶炼要求.  相似文献   

6.
几种高炉炉料冶金性能的对比研究   总被引:13,自引:1,他引:12  
系统研究了我国炼铁生产中几种常用炉料的高温冶金性能.结果表明:孔隙率发达的高碱度烧结矿的还原度最高,其次是进口球团矿和进口块矿,国内球团矿的还原度最低;但进口球团矿和进口块矿的低温还原粉化指数高于高碱度烧结矿;无论国内还是进口球团矿,其软化开始温度、矿石熔滴温度,均低于高碱度烧结矿,但其矿石软化温度区间、矿石软熔温度区间均比高碱度烧结矿要窄;南非块矿的最大压差最大,高达5.669 kPa;在各种炉料中,虽然钒钛块矿的还原度最低,但低温还原粉化指数最高,其软熔区间最窄,是一种合适的护炉炉料.  相似文献   

7.
烧结矿入炉后,会在高炉上部发生低温还原粉化现象,严重时会影响高炉料柱透气性,破坏高炉顺行.为了改善烧结矿的这一性能,揭示烧结矿粉化机制,归纳了化学成分、添加物、微观结构、外部还原气氛和烧结工艺等对烧结矿低温还原粉化的影响,分析了改善烧结矿低温还原粉化性能的方法,为粉化机制研究、烧结配矿提供参考.  相似文献   

8.
高碱度烧结矿加酸性炉料正在我国部分高炉应用,其生产效果并不理想。通过对烧结矿进行转鼓指数、还原粉化指数、还原度等冶金性能的试验,分析了烧结矿在高炉块状带的冶金性能随碱度变化的规律,为酸性烧结矿搭配高碱度烧结矿的炉料结构的工业生产提供了理论依据。实验表明:酸性烧结矿的转鼓强度高于高碱度烧结矿约3%,但其还原性指数低于高碱度烧结矿约20%,不利于高炉发展间接还原。  相似文献   

9.
目前,高炉炉料主要以烧结矿为主,但烧结矿在高炉中上部低温还原条件下粉化现象严重,因此有必要对其粉化机理进行深入研究。本文综述了碱度、MgO和Al_2O_3等化学成分对烧结矿低温还原粉化性能的影响。结果发现:同一组分对不同烧结矿还原粉化性能的影响不同。本文对烧结矿低温还原粉化机理有了更全面的认识,可为烧结矿配料改善其粉化性能提供借鉴。  相似文献   

10.
本文对比了两种不同炉料结构,一种为46.83%酸性球团矿及53.17%高碱度烧结矿的综合炉料,另一种为单一的自熔性烧结矿;分析了它们的全炉物料及热平衡,并进行了两种条件下的Rist操作线分析,获得了高炉使用综合炉料的冶炼效果比单一的炉料结构优越的结果.通过对原料冶金性能的测定,发现杭钢酸性球团及高碱度烧结矿具有较高的强度及还原性,较低的还原粉化率以及粒度整齐的特点,特别是酸性球团矿还具有低膨胀率的特点.文中指出其高温还原性能及软化温度有待改进,并提出了如何改进的办法.  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.
13.
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   

14.
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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16.
The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.  相似文献   

17.
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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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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