小铁山矿尾砂胶结充填絮凝沉降试验研究

絮凝沉降技术是小铁山矿尾砂胶结充填研究的主要内容之一。运用正交实验设计原理,对影响充填质量的各种因素间的关系进行分析,基于此分析结果,实施絮凝沉降试验,从而研究小铁山矿的尾砂胶结充填方法。研究结果表明:在充填料浆中添加6～8g/t聚丙烯酰胺,既能降低溢流水中固体物料含量和水泥离析,又能提高充填物料的沉降速度,同时还能改善充填体的形成状态,使充填体基本达到均质,提高充填体强度,使充填质量达到采矿工艺要求。     

碎石充填法处理复合采空区的应用实践

为了尽快消除隐患,降低空区事故发生,减少空区的危害程度,自2011年6月开始,经多次分析和论证,对D区深部1 280m复合空区以上部分,最终确定采用地表碎石充填钻孔为主,地表、地下微震监测系统24h无间断监测手段为辅的治理方案。该方案实施后提高了充填率,确保了空区再次处理的安全性,也为同类空区的处理提供了参考资料,值得借鉴与推广。     

HCNG加气站的设计及实现

氢气和天然气具有相近的燃烧特性,而HCNG作为这两种燃气的混合物,综合了氢气燃烧速率快、着火极限宽、可从可再生能源制取获得的特点,以及天然气体积热值高、储量丰富、排放较低等优点而成为清洁、环保的新型动力燃料。山西省是我国主要的焦炭生产基地之一,拥有丰富的焦炭及焦炉煤气资源,在山西运行HCNG项目,可以使焦炉煤气中的氢气得到有效利用,具有良好的经济、社会效益。HCNG加气站采用的工艺主要包括将混合前的氢气和天然气调成一个压力等级、进行两种气体的混合、对混合后的气体进行加压。项目实施过程中采用流量随动式混气机实现氢气与天然气的混合,采用带钢缠绕式储气罐作为HCNG储存设备。高压HCNG用于给汽车充装作动力燃料使用,低压HNG可直接提供给工矿企业、单位和居民作生产、生活燃料使用。     

Uniformity Differentiation Analysis of Powder Deposition Characteristics in Circular and Rectangular Shallow Dies Using Feed Shoe with Square Cross-Section

The inhomogeneity of the pressure distribution after completion of the filling process might create tablet and compact quality issues. Generating a uniform precompaction powder deposition into a die would minimize one source of tablet quality issues. This article determines the characteristics of the deposition process into a rectangular die and a circular shallow die, using a feed shoe with a square cross-section tube. A series of experiments were performed that determined the cumulative influence of particle size, die geometry, and feed shoe speed on uniformity of pressure distribution at the end of filling process. For uniformity comparison, the profiles of pressure distribution at the end of filling process were displayed as contour plots. Symmetry analysis, variance metrics, and uniformity analysis were implemented to quantify the deposition characteristics. Feed shoe speeds of 20 and 100 mm/s were used to fill the die. Due to their differing particle characteristics and importance, a pharmaceutical powder filler (microcrystalline cellulose-Avicel PH102) and a battery powder mixture (BPM) were used as test materials. The results showed that (1) contour plot was the most reliable method for evaluating uniformity deposition characteristics in dies; (2) based on contour plot analysis, BPM deposition at 100 mm/s feed shoe speed for circular shallow dies resulted in the most uniform pressure distribution among all, that is, 64% uniformity at ±20 dm (decimeter) resolution and 14.7% coefficient of variation (COV); (3) Avicel deposition at 20 mm/s feed shoe speed for circular dies had the least uniformity (46%); (4) rectangular dies generally had lower symmetry index (61%) in comparison with circular dies, which was attributed to sharp edges of rectangular die, that is, particles trapped in corners generated higher stresses inside the rectangular die versus circular die.     

Uniformity Differentiation Analysis. Part 1: Powder Deposition Characteristics in Rectangular Shallow Die Using Feed Shoe with Circular Cross Section

The process of die filling is a significant unit operation in many industries. Inhomogeneity of distribution such as in mass, bulk density, and pressure might cause many tablet and compact quality issues, such as lamination, capping, and distortion. No systematic investigations have been done to evaluate pressure distribution characteristics in dies with small aspect ratios (ratio of fill height to characteristic cross section dimension <0.5). In order to evaluate pressure distribution during filling of shallow dies, a circular cross section feed shoe was used at two speeds. The deposition characteristics of two powders with differing particle characteristics were studied in this research. The second-generation pressure deposition tester (PDT-II) was used to measure the two powders' pressure distribution characteristics. A battery powder mixture (BPM) and microcrystalline cellulose (Avicel PH102) were used to fill a rectangular shallow die 32 × 30 mm in dimension and 6.5 mm deep. Feed shoe speeds of 20 and 100 mm/s were used to fill the die. Symmetry analysis, variance metrics, Gini coefficient, and uniformity analysis were used to quantify the deposition characteristics. The results showed that (1) the contour plot was the most reliable method for measuring powder deposition characteristics; (2) the leeward and forward pressure distrbution comparisons generated a larger symmetry index than the front and back pressure distribution; (3) based on contour plot analysis, BPM at 100 mm/s feed shoe speed resulted in the most uniform pressure distribution (64% uniformity at +/?20 dm (decimeter) resolution) among all; (4) feed shoe speed greatly influenced pressure distribution uniformity inside the die; and (5) the high stress zone was mostly observed in forward and back regions inside the die.     

等离子体增强化学气相沉积技术制备锗反蛋白石三维光子晶体

采用溶剂蒸发对流自组装法将单分散二氧化硅(SiO2)微球组装形成三维有序胶体晶体模板,以锗烷(GeH4)为先驱体气用等离子增强化学气相沉积法在350℃填充高折射率材料锗.获得了锗反蛋白石光子晶体.通过扫描电镜、X射线衍射仪对锗反蛋白石的形貌、成分、结构进行了表征.结果表明:锗在SiO2微球空隙内填充均匀,得到的锗为多晶态.锗反蛋白石光子晶体为三维有序多孔结构.等离子体增强化学气相沉积的潜在优势在于可实现材料的低温填充,从而以高分子材料为模板进行复型,得到多种结构的三维光子晶体.     

液氯汽车罐车充装站工程设计

以有关规范为依据,介绍液氯汽车罐车充装站的工艺设计、总图及设备布置、配管设计、安装验收、电气自控和充装安全等。     

高附着力填剂的制备及施工应用

介绍了制备高附着力填剂时,树脂、填料、溶剂及防沉剂的选择。结果表明,采用极性醛酮树脂配合硅灰石粉及高填充功能性粉体作填料制备填剂具有优异的填充性及附着力,配合格丽斯色母调色涂装后可使木材纹理更清晰,同时具备填充与着色双重功能,可有效减少底漆的喷涂数量,提高生产效率,降低涂装成本。     

CNG汽车加气站工艺系统的安全性分析

本文首先简要介绍了车用CNG技术,并以此为起点,对车用CNG技术的安全性作了较为全面地分析,最后得出相应的防范与事故处置结论。