FX660旋流器组优化升级试验研究

银山矿业6500t/d铜硫选矿厂一段磨矿系统采用SABC流程,磨矿分级作业采用8台FX660旋流器(4开4备),该系统投产以来,随着生产的逐步稳定,磨矿系统台效由投产初期的270.8t/h提高到300t/h,旋流器溢流中-74μm级别含量达到65%以上,但+178μm级别含量达到9.36,略高于计划要求。为了降低旋流器溢流中+178μm级别的含量,对FX660旋流器进行优化升级,采用蜗壳预分级进料体新结构旋流器,同时对旋流器溢流管和沉砂嘴直径进行调整,将旋流器溢流中+178μm含量降低了3.02个百分点,-74μm级别提高了1.85个百分点,旋流器分级效率提高了1.77个百分点。分级作业返砂比降低了29.23个百分点。     

一段磨矿分级采用水力旋流器替代螺旋分级机的应用研究

针对云南某多金属选矿厂一段磨矿分级效率低,溢流细度提升小的问题,采用水力旋流器替代螺旋分级机。经过小试和工业优化试验,最终确认了采用FX500-GX旋流器作为一段分级旋流器。试验结果表明,使用旋流器替代螺旋分级机后,磨矿效果和分级指标有明显提升。磨矿分级设备均可通过DCS自动化控制系统控制,提高了磨矿分级工艺流程的稳定性,最终磨矿产品粒度组成更加均匀,过粉碎减少,为后续作业创造了良好条件。同时,球磨机平台噪声分贝有明显下降,有利于减少现场操作员工的职业健康危害因素。     

某钒钛磁铁矿二段旋流器分级工业试验

某钒钛磁铁矿二段闭路磨分系统采用常规旋流器进行浓缩分级时，存在溢流产率低、沉砂夹细高、循环负荷高等问题，针对以上问题进行了二段旋流器分级工业试验。研究结果表明：大锥角旋流器的应用在保证溢流细度的前提下，溢流产率提高了8.78个百分点，沉砂夹细降低了4.12个百分点，循环负荷得到大幅度降低，其分级效果显著优于目前的旋流器；同时可减轻过磨现象，钛精矿TiO₂回收率提高了2.05个百分点，在钒钛磁铁矿二段磨分工艺中具有推广应用价值。     

水力旋流器在铜炉渣磨矿分级工艺中的应用

铜炉渣的磨矿分级作业存在分级浓度高、要求分级粒度细、磨矿负荷高的特点,新型旋流器通过控制旋流器进料紊流和阻力、减少溢流管处短路和控制分级空间等方面的优化,改善了旋流器的分级流场,提高了旋流器的分级效率,并在一定程度上可以提高磨机的磨矿效率和降低能耗。在铜炉渣磨矿分级中的应用实例表明,结构优化后的水力旋流器对铜炉渣磨矿分级工艺的发展有着积极的促进作用。     

浅析南芬选矿厂水力旋流器替代螺旋分级机的应用实践

通过对比水力旋流器与螺旋分级机的工作原理和特点。介绍了南芬选矿厂采用水力旋流器替代螺旋分级机进行分级的实践情况,实践表明了该磨矿分级系统的溢流细度、分级效率、循环负荷、磨矿效率等均有显著提高。     

瓷球磨矿在湖南柿竹园公司中的工业应用

为了解决湖南柿竹园公司钢球磨矿存在的高能耗、粒度分布特性差、钨过粉碎严重等问题,以柿竹园选矿厂中二段磨和三段磨给矿作为研究对象,进行了瓷球磨矿的工业化应用,对比了瓷球替换前后磨矿效果和节能降耗变化。磨矿效果表明,瓷球介质优于钢介质,使得瓷球磨矿下分级回路中的循环负荷减轻,分级质效率和量效率也得到明显提升。同时瓷球磨矿可以改善磨矿产品的粒度及金属分布,减轻过粉碎,使合格粒级中有用金属更多。其中,二段磨溢流产品中钨金属在合格粒级中的分布率高出钢锻产品7.2个百分点,三段磨溢流产品中铁金属在合格粒级中的分布率高出钢球产品2.1个百分点。对比磨矿能耗可以发现,在二段磨矿中,磨机运行功率从506 kW降低至307 kW,介质消耗从0.47 kg/t降低至0.12 kg/t;在三段磨矿中,磨机运行功率从300 kW降低至200 kW,介质消耗从0.83 kg/t降低至0.14 kg/t。     

提高拜尔法格子磨磨矿效率的途径

本文结合氧化铝生产实际,通过分级设备、循环负荷、入磨矿石粒度等对磨矿效率的影响的分析,指出了完善和优化格子磨——旋流器一段闭路磨矿工艺和进一步降低入磨矿石粒度是提高磨矿效率的有效途径。     

有效提高拜尔法格子磨磨矿效率的途经

本文结合氧化铝生产实际,通过分级设备、循环负荷、入磨矿石粒度等对磨矿效率的影响的分析,指出了完善和优化格子磨--旋流器一段闭路磨矿工艺和进一步降低入磨矿石粒度是提高磨矿效率的有效途径.     

提高Ⅱ段磨矿旋流器分级效果的生产实践

主要针对Ⅱ段磨矿分级作业旋流器在应用过程中存在的问题，通过开展系统除杂研究、给矿变频控制以及新型旋流器试验等措施，稳定了旋流器工作状态，提高了旋流器分级效率，同时也改善了Ⅱ段磨矿效果，优化了各项生产技术指标。     

如何有效提高拜尔法格子磨磨矿效率

本文结合我厂生产实际,通过对影响拜尔法格子磨磨矿效率因素进行分析,特别对分级设备、循环负荷、入磨矿石粒度等因素对磨矿效率的影响进行了分析研究,指出格子磨-旋流器一段闭路磨矿工艺经过完善和优化;进一步降低入磨矿石粒度,是山西分公司提高磨矿效率的有效途径,通过生产实践证明,格子磨加旋流器一段闭路磨矿流程是目前拜尔法原矿浆制备工艺提高磨矿效率,保证矿浆细度的最佳选择。     

转炉炉壳热应力分析

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。     

焦炭热性能指标意义浅析

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。     

Results of treatment of cancer of the cardia

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.     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

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)     

Comparison of rates of infection of two methods of emergency ventricular drainage

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.     

浅析《野草》的版画特征

鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".     

四辊破碎机车刀架的改造

针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。     

Effect of antibiotics of chemotaxis of human leukocytes

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.