小粒径支撑剂在薄差层压裂施工中的应用

中原油田薄差油层多,分布较广,泥质含量高,部分井上下泥岩隔层厚,应力比较集中,造成压裂目的层裂缝缝宽较窄,压裂施工加入425～850μm陶粒,在22%左右砂比段经常出现砂堵。在铺砂浓度相同的条件下,闭合压力高于40MPa时,选用的粒径为300～600μm的小粒径陶粒作为主压裂支撑剂,与425～850μm陶粒相比导流能力相差很小。小粒径陶粒容易被携砂液携带,进入缝口时与较窄的裂缝宽度相匹配,施工砂比大幅度的提升,施工成功率100%。压裂施工后产量喜人。     

基于ANSYS的铁尾矿砂混凝土冻融循环温度应力分析

铁尾矿是一种在采矿的过程中被筛选出来无法作为矿石利用的"废弃物",累计量约为600亿吨1,其占用大量的土地并造成严重的重金属污染,随着河流中天然砂存量的日益减少,以铁尾矿为原料制成的铁尾矿砂混凝土逐渐成为新兴建筑材料,但在我国寒冷地区存在广泛的铁尾矿砂混凝土冻融现象,本文采用ANSYS有限元分析软件对铁尾矿砂混凝土进行冻融循环模拟,获得温度应力随时间变化的规律,这对发现铁尾矿砂混凝土在冻融循环下内部应力变化规律有重要的作用。     

干法重介质流化床多元加重质流化特性与低质煤高效分选

煤炭气固流态化干法分选是干旱缺水及高寒地区细粒煤分选提质、矿物加工以及固废资源化的重要途径,工业应用潜力大。目前,用于分选的流化床已有较多研究,其基础理论研究也较为深入,研究领域包括流化床的形成、流化床空气动力学以及流化床流动模型与模拟等,但干法重介质流化床的低密度分选技术和密度调节范围仍待完善。加重质的合理选择对干法重介质流化床选煤具有重要意义,其与流化床干法选煤系统的净化回收流程、分选机的操作参数及分选效果密切相关。采用干法重介质流化床对二元加重质单一组分、窄粒级、宽粒级以及三元加重质在流化床中的流化特性进行研究,对比分析磁铁矿粉、硼铁矿粉流化特性、膨胀率与粒度的关系。试验结果表明,磁铁矿粉和硼铁矿粉均能达到良好的流化状态。随加重质粒度的减小,起始流化气速显著降低,膨胀性能逐渐增强。与150～125μm硼铁矿粉和74～45μm磁铁矿粉混合相比,125～74μm硼铁矿粉与74～45μm磁铁矿粉混合后的床层压降波动较大。300～74μm粒级硼铁矿粉与74～45μm粒级磁铁矿粉在9种不同质量配比下,床层压降均无明显波动。随加重质粒度的减小,膨胀性能逐渐增强;窄粒级二元加重质混合均匀程度随硼铁矿粉含量的增加而提高;宽粒级二元加重质混合时,稳定流化后的流化曲线随细粒级的增多而波动加剧,难以形成稳定的分选环境;随着煤粉含量增加,三元加重质的流化效果逐渐变差。为保证流化床床层密度较好的均匀稳定性,三元加重质中煤粉含量不宜超过15%。     

铁尾矿砂对混凝土工作性的影响

通过正交试验,研究了铁尾矿砂占混合砂比例、砂率及浆骨比等因素对铁尾矿砂混凝土工作性的影响.结果表明,在选定的三个因素中,铁尾矿砂占混合砂比例是影响混凝土工作性的主要因素,在用水量相同条件下,当混合砂的细度模数为2.6～3.0时,铁尾矿砂混凝土的坍落度最大,粘聚性和保水性良好.     

铋矿加工由铋矿砂制备铋之无机化合物

(一)前言铋矿加工试验之目的,系以国产铋矿砂用原料,制备种种铋之化合物,以作化学药品,医药品,或其他工业上之用途。工商界通常多利用冶金方法,从铋矿砂提炼金属铋,再制成铋化合物。本试验则以铋矿砂为起点,用化学方法制备之。无机化合物之已制成者,计有铋酸钠,硝酸铋及硝酸氧铋等。铋酸钠多用于化学方面,例如分析锰时甚为重要。硝酸铋亦用于化学药品方面,且可用以制备,其他铋化合物;硝酸氧铋,则大量用于医药。本试验系以实地方法推进之,是为铋砂加工新法之尝试。     

铁尾矿砂混凝土受压作用下破坏演化特征

将铁尾矿砂作为天然砂替代物应用于混凝土工程可减少天然砂的开采,实现资源环境的优化配置。针对铁尾矿砂混凝土的损伤破坏,采用VIC-3D数字成像技术研究平面应变特征。结果表明,铁尾矿砂混凝土单轴抗压强度高于普通混凝土,损伤破坏过程属于脆性破坏;铁尾矿砂混凝土受压损伤破坏经历局部到整体的过程,与普通混凝土一致,应力传递不规则是导致其破坏的主要原因,裂纹由应力集中区域萌生,并沿强度薄弱区域拓延,最终裂纹贯穿试样破坏。     

用显微镜测定水泥中矿渣掺量

近年来,国外研究报导证实,通过取不同粒级(如200～90、90～60、63～50以及32～40μm等)矿渣,用显微镜测定其在水泥中掺量的可靠性、快速性及准确性较好。 用显微镜测定水泥中矿渣含量时,仅需1克试样。现以80～60μm粒级为例,取1克水泥试样,先用0.080μm方孔筛过筛,再用0.060mm方孔筛过筛,即得到粒级试样。刮铲少量试样放到载玻片上,搅拌一阵,将试样用醋酸铅的醋酸溶液浸泡3～5秒钟,浸泡前无色透明的矿渣颗粒即着色成黑色,而硅酸     

环流预汽提组合旋流快分系统粒级效率的三区计算模型

在大型提升管冷模实验装置上,系统地考查了带有环流预汽提的旋流快分(CVQS)系统的气相流场和粒级效率。结果表明,随着旋流快分系统喷出口气速的增加,粒径小于7μm颗粒的粒级效率的变化较小,7~20μm颗粒的粒级效率逐渐变小,而超过20μm颗粒的粒级效率则逐渐增大。根据CVQS快分系统的气固分离原理和结构特点,建立了计算CVQS系统粒级效率的三区模型。计算结果表明,在颗粒粒径大于20μm时,模型预测的粒级效率与实验值吻合较好,其最大相对偏差不超过6.1%;在颗粒粒径小于20μm时,模型计算的粒级效率与实验值相差较大,其相对偏差在45.7%~80.3%之间变化,并且随着颗粒粒径的减小,其相对偏差逐渐增加。模型对于主要用于分离20μm以上颗粒的CVQS系统的工程设计,具有重要参考价值。     

固废基路用胶凝材料配制及性能研究

以粉煤灰、电石渣、脱硫石膏、钢渣、矿渣等工业固体废弃物为主要原料,配制道路水稳层路用胶凝材料,全部或部分替代路用水泥,开展原料预处理加工和配比优化实验,考察原料细度和原料配方对胶凝试块强度的影响。结果表明：通过粉磨机械力活化,可明显增强固废的胶凝活性,其中,适宜的粉煤灰、电石渣、脱硫石膏、矿渣粉的中位径D50范围为8～12μm,而适宜的钢渣微粉中位径D50为5～8μm之间;通过固废超微粉原料间配方优化,可获得7 d和28 d强度分别为29.3 MPa和37.5 MPa的70%固废掺加量的无机胶凝粉体材料,该固废优化配比为粉煤灰：电石渣：脱硫石膏：钢渣：矿渣=31.8∶13.6∶9.1∶27.3∶18.2,按比例加入30%P·S42.5水泥,在此配方体系下,胶砂试块强度可以达到或超过纯路用32.5水泥强度指标。     

广西气刀土高分散性能对卫生陶瓷性能的影响

用美国LS230激光粒度分析仪测定了气刀土原料的颗粒组成，其分散后的颗粒组成处于微米一亚微米级范围，数量分布统计数据为≤1．0μm粒级达97％以上。平均颗粒仅0．255μm，具有高分散性能；在坯料中加入4％～7％的广西气刀土原料替代等量的苏州土原料，使制品体积密度增加、气孔率和吸水率降低。分析原因是气刀土的高分散性能促进了坯体的固相烧结所致。     

熔盐法制备岩层形貌氧化镁粉体的研究

以MgCl_2·6H_2O、CaCO_3和LiCl为原料,采用熔盐法制备了岩层形貌MgO粉体.借助热重-差示扫描热量计(TG-DSC)、X射线衍射仪(XRD)、场发射扫描电子显微镜(SEM)等手段对反应过程及产物进行了分析和表征.结果表明,430 ℃保温3 h热处理,产物中有MgO生成,600 ℃保温3 h热处理,产物经无水乙醇洗涤后,全部为MgO晶体;原料在650 ℃下保温3 h热处理,用水浸泡得到的氢氧化镁为不规整的片状形貌,分解为氧化镁后变成颗粒状形貌,粒径介于0.1～0.6 μm之间;EDTA-PEG溶液浸泡得到的氢氧化镁为四面体形貌,分解为氧化镁后为岩层形貌,大部分在顶角处有缺损,最大边长可达1.5 μm,表层粘附着少量颗粒状氧化镁,表面不平整.     

Development of novel refractory ceramic continuous fibers of fly ash and comparison of mechanical properties with those of E-glass fibers using the Weibull distribution

This study aimed to develop manufacturing technology for high-strength refractory ceramic fibers (RCFs) using fly ash, which is a highly promising material for the exterior and thermal insulation industry. The technology also contributes to reducing the environmental pollution caused by landfilling fly ash after coal is burned. Fly ash discharged from a thermal power plant, which had aluminosilicate chemical compositions, was used as the main material. As auxiliary materials, basalt, anorthite, feldspar, dolomite, and calcite were used to adjust the melt flowability, and frit, silica sand, and burr stone were used to lower the melting temperature. Moreover, the development of aluminosilicate fly ash fiber has the advantages of lower cost for raw materials and processing. Fly ash and natural rocks are inexpensive, and most of all, unlike the case for glass fiber production, the high cost of B₂O₃ is not a necessary expense. Fly ash is retrieved in powder form, which is advantageous compared to the starting materials for glass; the grinding process of raw materials can be skipped. From the fibrilization index calculation, we showed that the spinnability was influenced by the chemical composition of the salt-forming oxides in the fly ash compounds. We also found a correlation between the winding speed and the fiber diameter. The mechanical properties of a series of fly ash fibers were assessed by the Weibull distribution and then compared with those of the E-glass fibers that were melt-spun under an analogous condition.     

A multi-phase AC arc discharge and its application in in-flight thermal treatment of raw glass powders

The in-flight melting technology with multi-phase alternating current (AC) arc was developed for the purpose of saving energy and shortening production cycle for glass industry. The 6-phase arc and 12-phase arc were used to investigate the in-flight melting behavior of soda-lime and alkali-free glass powders. Results showed that the vitrification degree of raw materials and the shrinkage of particle diameter increased with the increase of input power. The higher melting temperature and viscosity were responsible for the lower vitrification degree of alkali-free glass powders. Compared with 6-phase arc, 12-phase arc improved the vitrification degree of raw material for the longer residence time and higher plasma temperature under the same transformer current. The high vitrification degree achieved in short time indicated that the new in-flight melting technology with multi-phase ac arc would be a promising method for energy conservation in glass industry.     

玻纤增强尼龙材料熔接痕强度初探

制备了不同黏度的尼龙6或尼龙66与不同直径的玻纤的共混物,对玻纤增强尼龙材料的熔接痕强度进行了研究。结果表明:使用相对黏度为2.4的尼龙6或2.4的尼龙66,其熔接痕都要比相对黏度为2.7的尼龙6或2.7的尼龙66高;在相同黏度尼龙6或尼龙66体系中,使用10μm直径玻纤要比使用13μm直径玻纤的熔接痕强度高。同时从扫描电镜可知:尼龙树脂对直径为10μm玻纤的包覆,要优于对直径为13μm玻纤的包覆。     

Gas-liquid mass transfer in a two-stage draft tube gas-liquid-solid fluidized bed

Experiments were conducted to study the gas-liquid mass-transfer characteristics in a two-stage draft tube gas-liquid-solid fluidized bed (DTFB). The DTFB was operated at essentially zero liquid velocity and superficial gas velocities up to 250 m/h. The sodium sulphite oxidation method coupled with an analysis of the off-gas concentration was utilized to determine the mass-transfer coefficients in each of the two stages and the overall mass-transfer coefficient for the two-stage DTFB. The particles used in the study were glass beads of 300 and 600 μm diameter and activated carbon particles of 307 and 714 μm diameter. The overall mass-transfer coefficient for the two-stage DTFB was compared with that for the single stage or one-stage DTFB.     

瓷石尾砂工艺玻璃制品的研制

在对瓷石尾砂工艺矿物特性研究的基础上,以瓷石尾砂为主要原料,取代石英砂和长石等原料,加以通用的玻璃辅助原料,成功地研制出透明和彩色尾砂工艺玻璃制品.配料中尾砂用量大,熔融温度低,成形性能好,成本低.研究结果表明,瓷石尾砂在玻璃工业中有着广阔的开发应用前景.     

含铍先驱体的合成与表征

以铍块、浓盐酸、乙醚、甲基镁、甲酸等为原料合成了含铍先驱体。采用XRD、元素分析仪、ICP、红外光谱对先驱体的组成、结构进行了表征。结果表明,先驱体中含有有机铍并且以-C-Be-C-形式存在。此外,所合成的先驱体经纺丝后可得到长度50～80cm、直径约100μm的有机纤维。     

High-speed photographic studies of impact on thin layers of emulsion explosive

A photographic study, at microsecond framing rates, has been made of the impact behaviour of thin layer samples of emulsion explosives. The experiments were performed using a drop-weight apparatus with transparent anvils. The effects of incorporating aluminium granules (∼100 μm in size) and glass microspheres (50 μm to 150 μm diameter) in the emulsion matrix were also studied. It was possible to record the flow of the emulsion both with and without additives. Of particular interest were observations of the onset and development of crystallization in the layer. In no case was there evidence for initiation of explosion.     

低介电常数NaF-ZnO-P_2O_5-B_2O_3玻璃的研究

低介电常数材料分为有机和无机低介电常数材料,含氟低介电常数材料主要应用于电子行业,可以降低集成电路的漏电电流、导线之间的电容效应和集成电路发热等。选定氧化锌、氧化磷、氧化硼以及氟化钠作为低温低介电常数玻璃的原料,研究了不同ZnO、B2O3配比下的玻璃样品的介电性能和耐水性能,结果表明,随着ZnO摩尔分数的增加,材料的介电常数有所下降;随着B2O3摩尔分数的增加,材料的耐水性能有所下降。     

硼酸镁晶须的制备与表征

以氢氧化镁、硼酸为反应物,氯化钠-氯化钾混合作助熔剂,高温固相合成法合成硼酸镁晶须。通过正交实验探讨硼酸镁晶须制备的最佳工艺条件:原料镁硼摩尔比1∶1,原料与助熔剂摩尔比1∶1.5,800℃高温固相合成2 h。采用X射线衍射仪和扫描电镜对硼酸镁晶须结构表征及表面相貌观察分析,所制备的硼酸镁晶须长度20μm,直径1.5μm针状晶体。对硼酸镁晶须合成过程进行了探讨分析。