高铁三水铝石型铝土矿的烧结特性

以Al2O3含量为26.35%,总Fe含量为31.22%,铝硅比为3.17的某高铁三水铝石型铝土矿为原料,研究了碱度、焦粉用量、混合料水分等对烧结矿质量指标的影响。结果表明:烧结矿碱度增加时,其转鼓强度和成品率下降,烧结矿自粉化程度加重;焦粉用量增加时,烧结矿转鼓强度和成品率提高;当混合料水分为9.0%、焦粉用量为8.0%、烧结矿碱度为4时,烧结矿转鼓强度为69.1%,成品率为81.2%,垂直烧结速度为30 mm/min,利用系数为1.2 t/(h.m2);烧结矿碱度为4时,样品存放2天粉化率为5%,烧结矿平均粒度由22.2 mm减小到21.9 mm,延长存放时间,烧结矿自粉化率增大,平均粒度显著减小。该烧结矿的冶金性能能基本满足高炉冶炼的要求。     

Desilication from illite by thermochemical activation

Illite occurs widely in bauxite ores and results in low alumina grade of the ores. Differential thermal analysis (DTA), thermal gravimetric analysis (TGA) and X-ray diffraction analysis (XRD) show the OH groups split off from the structural framework of illite between 500 ℃ and 700 ℃. With the increase in temperature up to about 1 100 ℃, the layer structure of illite breaks up and Si in the layers is transformed into the amorphous state. Meanwhile, mullite comes out at 1 100 ℃. Quartz occurring in illite keeps unchanged in structure in the range of 500 -1 200 ℃. A desilication process from illite by thermochemical activation followed by alkali leaching is therefore developed on the basis of the behavior that amorphous silica is alkali soluble. The investigation finds that the optimum parameters for desilication are activation temperature of 1 100 - 1 150 ℃, activation time of 90 - 120 min, leaching temperature of 95 - 110 ℃, leaching time of 90 - 120 min and concentration of caustic soda (Na2Ok) 120 - 150 g/L. An overall desilication about 45% is attained under these conditions. XRD analysis confirms that the active amorphous SiO2 has been dissolved in the alkali solution and removed from the samples, while quartz and mullite have not. The investigation also shows that the formation of mullite during activation and formation of sodium hydroalu minosilicates (Na96 Al96 Si96 O384 and 0.95Na2 O · Al2 O3 · 3.25SiO2 · 4.79 H2 O) during leaching lead to the relatively low desilication of illite.     

铁精矿粒度对球团强度的影响

以大红山、曼南坎和滇滩等精矿的粒度以及膨润土用量和润磨时间为因子,以生球落下强度、生球爆裂温度、预热球抗压强度和焙烧球抗压强度为评价指标,进行了五因子二次回归组合实验研究。结果表明:随着铁精矿小于0.074mm粒级含量的增加,生球爆裂温度下降,预热球和焙烧球抗压强度提高;当铁精矿小于0.074mm粒级含量小于75%(质量分数)时,生球落下强度逐渐上升,当小于0.074mm粒级含量为75%时,生球落下强度达到最大值,之后有下降趋势。并不是铁精矿粒度越细球团强度就会越好,铁精矿粒度还应该满足一个合适的粒度组成。     

无碱玻璃纤维行业及其所用耐火材料现状

无碱玻璃纤维由于良好的耐水性,良好的电绝缘性和机械强度等优点,在玻璃纤维产业中所占的比例越来越大。无碱玻璃池窑拉丝是当今世界玻璃纤维工业最先进的生产方法,而单元窑是熔制难熔优质玻璃的首选窑型,由于无碱玻璃纤维熔制温度在1540℃以上,所以对所用耐火材料的要求也十分苛刻。本文综述了无碱玻璃纤维行业及其所用耐火材料现状,指出了在当前形势下。致密氧化铬砖仍是无碱玻璃纤维池窑关键部位的首选耐火材料。     

高职院校计算机基础课程理实一体化教学的探索

高等职业院校的办学特点就是要培养适应社会需要的高技能应用型人才,高职院校计算机基础课程是一门实践性较强的课程,教学的组织和实施不能照搬以学科体系为中心、以传授系统的理论知识为主体的教学模式,必须改变传统教学方法,改革教学手段,增强实践能力,推行理论一实践一体化的教学模式。     

Sodium-modification of Ca-based bentonite via semidry process

In order to improve the quality of Hunyuan inferior Ca-based bentonite (Ca-Bent), semidry process was used to modify Ca-Bent into superior Na-based bentonite (Na-Bent). The factors affecting sodium-modification were investigated. The optimized experimental parameters are obtained as follows: Na₂CO₃ dosage 4.0%, ageing time 25 d, briquetting pressure 25 MPa and briquetting moisture 20%. Under the optimization conditions, the modified Na-Bent has a colloid value of 73.6 mL/(3g), dilation of 38 mL/g and water absorption in 2 h (2HWA) of 465%, respectively. The balling results indicate that the modified Na-Bent pellets have higher drop strength and compression strength than the Ca-Bent pellets.     

基于移动机器人定位和导航的人工路标设计

在复杂环境下,如何快速、准确地识别路标是移动机器人定位和导航的关键问题.基于图像分割原理,利用投影和方向特征的处理方法,提出了一种新的人工路标方案.通过统计学的相关理论验证了该路标图案的可行性,实验结果也显示了该图案可以较好地解决移动机器人的路标识别问题.     

沈从文女性崇拜的心理探微

沈从文的女性崇拜极具现代品格,这使得其在现代作家中独树一帜。他提出重建民族品德,并将女性视为重塑民族品德的载体。这种优化女性的做法不具有女权或革命意义,它深受民族心理与习俗的影响,也与其个人的经历密切相关。探求其女性崇拜背后的心理隐秘,有助于从创作心理上解读沈从文的作品。     

陶瓷压机随动模框装置的设计

随着陶瓷行业的发展、人们消费水平和市场需求的提高,消费者对墙地砖的要求也越来越高,高档产品如抛光砖、渗花砖、耐磨砖等越来越受到青睐。生产厂家为了赢得更大的市场,也正往大规格、高档次的方向发展。以往不同型号压砖机的控制系统只是针对普通墙地砖而设计的。普通墙地砖     

水泥磨机外壁冷却水结垢的清除方法

禹王公司的φ2.2m×6.5m水泥磨熟料入磨温度高达280℃,为了降低磨体温度,在筒体外喷洒冷却水.由于工作环境粉尘很大、冷却水水质偏硬,简体外壁形成结垢层,厚达12mm,不利于磨体降温.