Grinding of mineral mixtures in high-pressure grinding rolls     

Abdel-Zaher M. Abouzeid  Douglas W. Fuerstenau 《International Journal of Mineral Processing》2009,93(1):59-65

Attempts at improving comminution machines generally have been directed towards increasing the performance efficiency, particularly increasing throughput rate and decreasing energy consumption. The latest and most successful new comminution technology has been the high-pressure grinding rolls (HPGR), which have proved to be highly efficient in energy consumption and to have a relatively high throughput rate at low steel consumption. Already used extensively in cement plants worldwide, the first HPGRs in the mineral industry were installed in plants processing diamond ores. They are now finding their way into the large-scale base-metal mining industry. Since feed constituents in natural ores vary in their physical properties such as hardness, plasticity and brittleness, the present paper is concerned with an investigation of the behavior of a heterogeneous feed as it passes through the HPGR. The effect of feed composition on operational parameters, the energy efficiency of comminution, and energy distribution among the feed components is addressed. Mineral particles with high hardness act as energy transfer agents in the roll gap and enhance the grinding of softer mineral particles in a mixed feed.  相似文献   

年尺度地震预测模型的国际研究现状     

尹凤玲  蒋长胜  姜丛 《地球与行星物理论评》2021,(1)

对未来1年内发生强震的预测在做好备灾应急准备和防震减灾工作上具有重要的现实需求.为反映近年来国际上关于1年尺度地震预测模型研究的进展,本文系统地整理了地震的统计概率预测模型、物理预测模型和混合预测模型,并从方法原理、预测效能评价、部署应用等角度进行了梳理.研究表明,目前国际上发展的1年尺度地震预测模型及其效能评价使用的参考模型的总体数量较少、建模原理主要基于G-R关系等统计学基本定律,显示该领域在基础理论架构、关键技术体系上并未足够成熟,这可能与相应的地震发生机理解释尚不完善、建立数理化的预测模型尚有困难等因素有关.  相似文献   

黔江台水管仪与垂直摆预报效能对比分析     

龚丽文  陈丽娟  吕品姬  张燕  郭卫英  肖家强 《地震》2021,41(4):168-179

水管仪与垂直摆均是通过观测地倾斜变化来捕捉地震前兆信息的定点形变仪器, 但因工作原理和观测频段不同, 其观测结果和异常形态具有一定差异性。 因此, 对两种仪器的不同异常形态进行预报效能评估具有重要意义。 利用异常自动化处理软件, 提取黔江台倾斜仪各测项趋势转折、 速率变化、 破年变和潮汐因子等常见异常, 并结合区域范围内的地震, 对不同异常进行R值评分, 评估不同测项的预报效能。 结果显示: 垂直摆NS分量预报效能最高, 其趋势转折异常和M2潮汐因子异常均具有较好的预报指示意义; 两套仪器的EW分量分别在破年变和速率变化预报效能较高; 而水管仪NS分量预报效能最差, 可能与该测项仪器故障频繁有关。 此外, 不同测项的异常对应的地震分布也具有一定的规律性。  相似文献   

Quantitative Assessment of Hydrocarbon Expulsion of Petroleum Systems in the Niuzhuang Sag, Bohai Bay Basin, East China   总被引：1，自引：1，他引：0  

PANG Xiongqi  LI Sumei  JIN Zhijun  BAI Guoping Key Laboratory of Hydrocarbon Accumulation  Ministry of Education  Beijing  E-mail: pangxq@bjpeu.edu.cnBasin & Reservoir Research Center  University of Petroleum  Beijing Sinopec Petroleum Exploration  Exploitation Institute  Beijing 《《地质学报》英文版》2004,78(3):615-625

Based on a detailed survey of the distribution and organic geochemical characteristics of potential source rocks in the South Slope of the Niuzhuang Sag, Bohai Bay Basin, eastern China, a new approach to assess the amount of hydrocarbons generated and expelled has been developed. The approach is applicable to evaluate hydrocarbons with different genetic mechanisms. The results show that the models for hydrocarbon generation and expulsion vary with potential source rocks, depending on thermal maturity, types of organic matter and paleoenvironment. Hydrocarbons are mostly generated and expelled from source rocks within the normal oil window. It was calculated that the special interval (algal-rich shales of the ES4 member formed in brackish environments) in  相似文献   

页岩气地质调查皖含地1井施工工艺          下载免费PDF全文

赵亮  汪程林 《探矿工程》2019,46(4):42-47

皖含地1井是在和含巢逆冲推覆构造带中段巢湖背向斜构造带部署实施的一口地质调查井。目的在于获取巢湖-含山-无为地区奥陶系-志留系富有机质页岩的各类地质参数,为本区五峰组-高家边组页岩气资源潜力评价及有利区优选提供地质依据。本文主要阐述了皖含地1井的井区概况、钻探施工技术与施工工艺。施工中结合实际情况进行钻井质量控制,在钻进过程中合理调整钻进参数,有效控制钻井顶角,符合地质设计的目的。并对皖含地1井进行台效分析,为后期的钻探积累了经验。  相似文献   

涪陵页岩气田江东区块优快钻井技术研究与应用          下载免费PDF全文

黄迪箫笙 《探矿工程》2019,46(4):18-23

涪陵页岩气田江东区块地质构造复杂、地层倾角大,存在机械钻速低、定向钻井托压严重、水平井轨迹控制困难等问题,给该地区优快钻井作业带来了挑战。本文通过总结现场施工作业及技术攻关实践,分析总结了江东区块复杂地质条件下相适应的钻井新工艺、新工具,形成了一套适用于涪陵页岩气田江东区块的优快钻井技术。江东区块钻井周期从开发前期的235 d缩短至9033 d,机械钻速、储层钻遇率不断提高的同时,定向钻井托压、钻头提前失效等工况逐渐减少。通过4年发展,涪陵页岩气田江东区块优快钻井集成技术逐渐成熟,基本满足了深层页岩气的开发需要。  相似文献   

CO2驱微观可视化技术在超低渗储层中的应用可行性研究:以鄂尔多斯盆地为例     

李明  朱玉双  李文宏  袁国伟  杜朝锋 《现代地质》2019,33(4):911-918

CO₂驱油是提高特低渗、超低渗油藏驱油效率的重要途径,但目前由于匮乏CO₂驱油微观可视化实验技术,制约了CO₂驱油微观机理研究及驱油效果评价。本研究提出特低、超低渗油藏高温高压下CO₂驱油微观可视化实验技术,为该类油藏CO₂驱油机理研究提供良好的研究手段。以鄂尔多斯盆地超低渗储层为例,利用首次研制成功的高温、高压、防暴真实砂岩模型,成功进行了CO₂驱油微观可视化实验研究,首次镜下观察不同相态CO₂在超低渗储层复杂孔喉中驱替原油的动态现象,重新认识超低渗油藏注CO₂驱油时不同孔喉结构中CO₂赋存状态和渗流规律。结果表明,储层微观孔喉结构,尤其是孔喉大小分布的均匀程度,对CO₂驱油效率的重要影响超出预期,直接决定着CO₂能否进入储层以及其后的渗流路径。CO₂驱油微观可视化实验技术可有效进行CO₂驱油微观机理研究及驱油效果评价研究,并为后期进行油藏矿场试验提供指导意见。  相似文献   

Stormwater capture and antecedent moisture characteristics of permeable pavements          下载免费PDF全文

Rui Guo  Yiping Guo  Jun Wang 《水文研究》2018,32(17):2708-2720

An approach based on individual rainfall events is introduced to mathematically describe the hydrologic responses and estimate the stormwater capture efficiencies of permeable pavement systems (PPSs). A stochastic model describing the instantaneous dynamic water balance of a PPS is established, from which the probability distribution of the antecedent moisture content of the PPS at the beginning of a rainfall event is analytically derived. Based on this probability distribution and the event‐based approach, an analytical equation that can be used for estimating the stormwater capture efficiencies of PPSs is also derived. The derived analytical equation is verified by comparing its results with those from continuous simulations for a wide range of PPSs with different sizes and underlying soils and operating under various climate conditions. It was found that the antecedent moisture contents of PPSs at the test locations are usually fairly close to zero, suggesting that PPSs at these locations are always almost empty at the start of a rainfall event. The derived analytical equation accounts for many key processes influencing the behaviour and operation of PPSs; it may serve as an easy‐to‐use tool that is essential for the planning and design of PPSs.  相似文献   

基础设施投入效率时空演变及其关联格局研究——基于中国地级以上城市的实证     

韩增林  曹锡顶  狄乾斌 《地理科学》2021,41(6):941-950

城市基础设施效率研究是科学评价基础设施发展质量的重要环节。在构建城市基础设施投入效率评价指标体系的基础上,借助MaxDEA软件,运用DEA模型,对2006—2016年中国地级以上城市基础设施投入产出效率进行测度和分解,探究其时空演变特征,并通过ESDA方法分析其空间关联格局。研究结果显示：① 中国城市基础设施的总体投入产出效率整体水平不高,但呈现增长趋势,并且高效率等级城市也在均速增加,逐渐改变以规模投资为主,技术效率缓速提高。② 空间分布特征鲜明,大致呈现东高-中低-西高的分布格局,具有多数分散,小部分集中的特点。③ 城市基础设施投入效率空间关联集聚范围出现了位移,热点分布与其空间分布基本一致。  相似文献   

都市水源区村域社会−生态系统脆弱性空间分异的地理影响模式——以上海市青浦区为例     

任国平  刘黎明  李洪庆  季翔  赵旭 《地理科学》2021,41(8):1469-1478

以上海市青浦区为例,采用数据包络模型、空间自相关模型、多元Logistic回归模型、地理探测器和层次聚类模型分析该区184个行政村社会?生态系统脆弱性的空间差异及地理影响机制。研究表明：① 基于熵权集结交叉的“投入?产出”效率模型对村域社会?生态系统脆弱性评价结果更具可信度和精确性,2018年行政村社会?生态系统脆弱性空间上呈由东向西逐渐降低的变化趋势,脆弱性均值为0.583;② 地理因素对经济发达村域社会?生态系统脆弱性空间分异仍旧具有重要影响。距上海市中心距离、距淀山湖距离、距青浦区中心距离和水域面积成为影响该区社会?生态系统脆弱性的4种主导地理因素,其地理影响力呈现系统结构空间差异和种类属性替代及程度转化;③ 依据地理因素影响力聚类分析将该区社会?生态系统脆弱性地理因素空间耦合模式分为10种,多地理因素耦合模式是主要决定类型,呈现中部多因素主导和两侧单因素主导并存的多元环状地域决定格局;针对不同类型提出调控区域社会?生态系统脆弱性的可行方式。  相似文献