稀土和合金成分对铁基自熔合金喷焊层耐腐蚀性的影响

采用熔炼—雾化工艺制备不同配方的铁基自熔合金粉末,进行了铁基自熔合金喷焊层在酸性和中性溶液中的腐蚀试验。结果表明,稀土和不同合金配方对铁基自熔合金在不同介质中腐蚀性能有不同影响。     

GN8型搅拌磨机产品粒度分布宽度的影响因素研究

为了研究GN8型搅拌磨机的磨矿效果,运用Rosin-Rammler分布函数分析了搅拌器转速、矿浆浓度和介质充填率对磨矿产品粒度分布宽度的影响规律。研究结果表明,增加搅拌器转速或介质充填率,有利于降低磨矿产品的粒度分布宽度;矿浆浓度在45%~60%范围内,其对磨矿产品的粒度分布宽度无影响。     

细粒矿物浮选研究进展

概述了细粒矿物对浮选影响的研究进展,包括细粒矿物的浮选回收、细粒对浮选的影响机制以及细粒矿物对粗粒矿物浮选的影响,为细粒矿物浮选的研究提供一定的参考。     

Field investigation of using water injection through inseam gas drainage boreholes to control coal dust from the longwall face during the influence of abutment pressure

Coal dust is a primary contributor to underground coal-mining disasters and is also a major factor in adversely affecting the occupational health of mine workers. Pre-wetting the coal seam with water injection is widely considered as one of the effective means of mitigating coal dust generation during mining. Injecting water through inseam long boreholes parallel to the working face is a commonly used technique. However, for most fully-mechanised top-coal caving working faces, inseam gas drainage boreholes are drilled to extract gas from the gassy seam prior to mining. Therefore, there is neither enough time nor space at the working site for an elaborated water injection process. Based on the mining conditions at Panel 9801 of the Yangquan coalfield, this study designed a water injection system through the inseam gas drainage boreholes to control dust arising from the longwall face. Under the influence of abutment pressure, water injection through a set of inseam gas drainage boreholes was experimentally investigated to offset the conflict between water injection and gas drainage in terms of the time and space availability. The relations between the amount of injected water, the injection rate, the seam moisture content and the coal dust level at the working space were investigated. The effect of water injection for dust control at different distances ahead of working face was assessed. With the change of abutment pressure, the effect of water injection to inseam gas drainage and gas emission at working face was revealed and a space-time balance between gas drainage and dust control by water injection was established. The results indicate that under the influence of abutment pressure, water injection through inseam gas drainage boreholes wetted the seam and decreased the dust level at the working face. Water injection only has marginal influence on inseam borehole drainage and has a negligible impact on the gas level produced at the working face. Under the influence of abutment pressure, the optimum area for water injection through the inseam boreholes was the primary fracture opening zone and the secondary fracture development zone.     

顺层钻孔水力压裂有效影响半径确定与抽采效果分析

为了增加煤层透气性,提高煤层瓦斯抽采效果,以某矿501工作面煤层地质条件为工程背景,采用理论分析、数值模拟、现场试验等方法,对某矿煤层起裂压力、单次压裂时间、压裂流量、影响半径、压裂钻孔抽采效果等参数展开研究。结果表明,模拟压裂孔注水1 h后,煤层压力由压裂孔向周围迅速降低,最终呈现出以压裂孔为圆心的圆形区域的致裂范围,最大压裂半径达到8.315 m;当对压裂泵主动升压至38 MPa时,煤层瞬间破裂,压力回降,流量瞬间增大,且达到压裂泵额定流量值,此时,煤体破裂效果完美;4号压裂孔首次压裂已经接近压穿煤体,进行第二次压裂时,流量曲线增加比较平稳,说明该孔在之前已贯通大部分裂隙,压裂半径可达22 m;对水力压裂孔和普通钻孔进行抽采比较发现,压裂3号钻孔的瓦斯浓度平均达到17.68%效果最为显著,与普通钻孔相比其平均浓度为1号普通钻孔的4.77倍、2号普通钻孔的3.12倍。     

天然气/液化气先进再燃脱硝特性研究

利用自行研制的可燃气体再燃脱硝实验台，在先进再燃脱硝的典型影响因素条件下比较了两种再燃燃料的脱硝特性.实验燃料先进再燃脱硝时均存在最佳过量空气系数、最佳NH₃/NO摩尔比；1 050,1 150 ℃时脱硝效率随再燃气/NO摩尔比增加而提高，而1 200 ℃时脱硝效率随天然气/NO比增加先升高后降低，实验最佳天然气/NO比为3.63；天然气/液化气先进再燃时再燃区最佳温度分别为1 250 ℃与1 050 ℃，再燃区温度高于1 150 ℃时选择天然气为再燃燃料，反之选择液化气；从停留时间上考虑应优先选择天然气作为再燃燃料.     

地下水曝气接触氧化法除铁除锰工艺及设计应用

介绍了在进行地下水处理设计中,应根据各地区地下水不同的特点采用不同的处理方法。论述了“曝气接触氧化法”除铁除锰时,在水的不同特点下的具体方案。     

红辉沸石的耐酸性研究

红辉沸石是辉沸石族矿物中的一种，属正交晶系，化学成分主要为SiO2和Al2O3，其次为CaO。利用化学成分分析和X射线衍射分析等测试手段，深入研究了不同浓度酸处理红辉沸石的主要化学成分及晶体结构变化特征，进而揭示了红辉沸石的耐酸性。研究表明，红辉沸石的耐酸性较差，其酸稳定浓度为约5％，结构完全破坏酸浓度为15％。酸处理后可成为非晶质的高硅质矿物材料。     

褐铁矿烧结成矿过程工艺矿相学研究

本文针对大宝山褐铁矿原料烧结,利用矿相显微镜查明了不同烧结时间,烧结温度和烧结碱度下各焙烧小团块的矿物组成与显微结构,揭示了褐铁矿烧结矿成矿的机理,找到了生成以针状铁酸钙为主粘结相的褐铁矿烧结矿的适合碱度、烧结温度及烧结时间,为褐铁矿低温烧结新工艺研究提供了理论依据。     

地面竖直荷载作用下采空区临界扰动深度及其稳定性研究

矿产资源开采后遗留的采空区,通过应力再分布达到新的平衡,并形成应力拱承载上覆岩层的重量。当采空区地表进行建设时,地面竖直荷载的增加可能会破坏采空区的应力平衡状态,诱发采空区"活化",导致安全隐患。为分析矿区地表开发利用适宜性,本文采用附加应力法和数值分析法,展开采空区地面竖直荷载作用下采空区临界扰动深度及其稳定性的研究。结果表明,当竖直荷载影响深度与采空区垮落、裂隙带顶部界面接触时,刚好处于临界稳定状态,结合矿区实际,计算得到矿区当荷载临界扰动深度为31.38m,并利用FLAC3D软件的模拟临界状态荷载(240kPa)下采空区的稳定性,为矿区地灾防治、土地开发利用提供必要依据。