Estimating coal reserves using a support vector machine

The basic principles of the Support Vector Machine (SVM) are introduced in this paper. A specific process to establish an SVM prediction model is given. To improve the precision of coal reserve estimation, a support vector machine method, based on statistical learning theory, is put forward. The SVM model was trained and tested by using the existing exploration and exploitation data of Chencun mine of Yima bureau’s as the input data. Then coal reserves within a particular region were calculated. These calculated results and the actual results of the exploration block were compared. The maximum relative error was 10.85%, within the scope of acceptable error limits. The results show that the SVM coal reserve calculation method is reliable. This method is simple, practical and valuable.

Application of open-pit and underground mining technology for residual coal of end slopes

Given the conditions of residual coal from the boundary of a flat dipping open-pit mine,which uses strip areas mining and inner dumping with slope-covering,we propose an open-pit and underground integrated mining technology for residual coal of end slopes.In the proposal a conveyance road and ventilation conveyance near the slope are built,corresponding to the pit mining area and the surface coal mine dump,as well as an interval haulage tunnel and air-inlet tunnel.The outcome shows that such mining method may reduce the effect to slope stability from underground mining,it does not affect the dumping advance and has a high recovery rate of residual coal resources.The working face is timbered by single hydraulic props,transported by a scraper conveyor and supported by coal walls.This method of mining is one of layered top coal caving,with high resource recovery,low production cost where positive economic benefit can be realized.

Thermal recovery process of a backfilled open-pit in permafrost area at the Gulian strip coal mine in Northeast China

Timely and proper backfilling of open-pits in strip coal-mines has been an effective measurement for the recovery of the hydrothermal regimes and ecological environment in permafrost regions. In this study, numerical simulations and statistical regressions were applied for analyzing the recovery processes of the backfill and its major influencing factors for the thermal equilibrium in recently backfilled open pits at the Gulian strip coalmine in Mo'he, Northeast China. Results show that the thermal recovery time of backfilled areas is positively correlated to the backfill depth(BD) of the soils, the backfilled soil temperature(BST), and the mean annual ground surface temperature(MAGST); meanwhile, climate warming can impact on thermal regimes of the backfill area. The impact of climate warming on ground temperature of the backfill will show up significantly in about 50 years afterbackfilling(BD at 10.0 and 20.0 m, BST at 20.0°C) under the climate warming scenario(CWS) of 0.025°C·year ^(-1). Grey-relation analyses show that the sensitivity of the backfill recovery time declines in the order of the BD, BST and MAGST. On the basis of the abovementioned studies, the layer-by-layer backfilling in cold seasons is advised for more effective and more rapid recovery of thermal regimes of the backfilled open-pits in cold regions.

Application of Artificial Neural Networks to the Classification of Coal Reserve Assets

Using the classification results by the fuzzy clustering models as the basis for choosing the choosing patterns, a feed forward networks model for classification is given. Remarkable success was achieved in training the networks to learn the patterns and in classifying the coal reserve assets. The results show that the neural network approach for classification has some advantages such as stability and reliability.

煤岩气:概念、内涵与分类标准

近年来,准噶尔、鄂尔多斯等盆地深层煤岩储层中的天然气勘探开发取得重大突破。针对目前工业界和学术界对这种新类型非常规天然气表述不一致的现状,在前人研究的基础上定义了“煤岩气”概念,并系统对比剖析其赋存状态、运储形式、差异聚集和开发规律。在地质上,煤岩气不同于传统意义上的煤层气,具有游离气与吸附气并存、富含游离气,自生自储-微距运移并可有他源的聚集,煤岩割理裂缝发育、游离气差异富集等特点,埋深超过2000m的深层煤岩气具有“高压力、高温度、高含气、高饱和、高游离”的“5高”地质特征;在开发上,与页岩气、致密气特征相似,人工改善储层连通性后,无需排水降压,高势能游离气弹性驱动产出、压降后吸附气解吸接替,可依靠地层自然能量开采,游离气与吸附气连续接力长周期产气。按照埋深、煤阶、压力系数、储量规模、储量丰度和气井产量等,提出了煤岩气的分类标准和资源/储量估算方法。初步估算埋深超过2 000 m的中国煤岩气地质资源量超过30×1012m3,是国家重要的战略资源。提出鄂尔多斯、四川、准噶尔和渤海湾等盆地是煤岩气的规模富集有利区,梳理了技术与管理挑战并指出攻关方向,为中国煤岩气管理与勘探开发奠定理论、评价和生产实践基础。

非常规油气高质量发展战略方向优选

近10年来,化石能源多样化趋势明显,从常规油气领域向致密油/页岩油、致密气/页岩气、煤炭地下气化等非常规领域发展。油气藏类型增多,资源规模、品位、勘探开发难度及效益存在差异。要实现不同类型油气藏规模效益开发及绿色高质量发展,必须对化石能源未来发展方向和类型做出选择。分析国内外能源消费结构变化规律、现状及未来发展趋势,煤炭和石油一直保持主体地位,天然气占比逐年上升。对比研究不同类型化石能源单位体积能量密度、资源规模、开发成本、开发现状、技术成熟度等主要指标,结果显示煤炭地下气化具有能量密度最高、可采资源量最大、开采成本低等特点,在增加天然气供应、推动煤炭行业绿色低碳发展和助力实现碳中和方面拥有技术优势,可优选为非常规油气战略方向,为高质量发展开拓新路径。

基于OpenGL的三维地质建模及资源量估算

OpenGL是用于渲染2D、3D矢量图形的跨语言、跨平台的应用程序编程接口,常用于CAD、虚拟现实、科学可视化程序和电子游戏开发,可以与Visual C++紧密接口,便于实现机械手的有关计算和图形算法,可保证算法的正确性和可靠性,尤其是矿产资源估算中具有良好的应用效果。本文以Python软件平台为基础,以某内蒙古鄂尔多斯上湾煤矿为例,根据已有的煤矿煤层数据资料建立煤层三维地质数学模型,对综采面煤炭储量数据进行估算,并将矿井综采面实际掘进回采数据做为对照组,数据表明,该方法的较传统块段法更准确可靠。

国内煤制天然气产业发展现状与趋势分析

我国自“十一五”开始煤制天然气示范项目建设,长期以来环保问题和经济性是制约煤制天然气产业发展的关键问题。双碳目标下,我国天然气消费量到2035—2040年将有巨大的增长空间,而国际天然气市场波动进一步提高了对供应安全的要求。煤制天然气作为现代煤化工的重要形式,有利于促进煤炭清洁低碳化利用。分析了我国煤制天然气产业的机遇和挑战,天然气多元化供应和安全储备需要给煤制天然气产业带来了历史性机遇,而终端市场竞争力不强和高碳排放等环保问题是该产业的长期挑战。分析了煤制天然气生产成本和到达终端市场的综合成本,在环渤海、长三角和中部地区3个天然气区域市场内,与其他多种气源的经济性进行了比较。结合煤制天然气产能和供应能力的增长趋势,预计2030年前我国煤制天然气市场需求呈上升趋势,煤制天然气将发挥丰富终端气源和应急供应的重要作用。

浅埋厚煤层大巷保护煤柱尺寸留设研究

留设煤柱护巷道目前仍是中国许多矿井的主要护巷道方式,但同时也损失了巨大的煤炭资源。煤柱留设的长度也是影响煤柱稳定性和巷道围岩稳定性的关键所在,其安全长度的留设,更有利于改变围岩应力分布条件,隔离工作面采空区,维护巷道围岩稳定具有重要的作用。区段煤柱留设宽度与煤矿采区埋置深度、工作面倾角、煤层高度、巷道顶底板围岩等具有相关联系。不同煤矿开采条件不同,不同矿区都有自己留设煤柱的宽度方法。因此,本论文针对某煤矿西翼带式运输大巷煤柱安全宽度等问题展开研究,分析煤柱内的应力分布、变形特征和塑性区分布,最终得出安全煤柱宽度留设,论证该尺寸煤柱下,确保被保护的巷道在掘进过程中不引起失稳,这对于煤矿的安全生产来说至关重要。

煤矿资源储量动态管理技术体系构建

强化煤矿资源动态管理是提高回采率的重要措施,也是监督矿产资源合理利用的重要依据。为阐明煤矿资源储量管理存在的问题,构建煤矿资源储量动态管理技术体系,系统梳理了煤矿资源储量动态管理相关的标准及文件,整理和分类了煤矿资源储量相关的主要技术指标。结合日常地测技术服务及煤矿资源储量报告评审工作,指出了煤矿在资源储量动态管理中存在的主要问题,构建了煤矿资源储量动态管理技术体系的初步模型,为实现煤矿资源的高效利用与安全生产的有机融合提供了借鉴。

资源储量估算方法在煤矿开采中的应用

为提高某煤矿煤炭储量估算结果的准确性,应用普通克里格法、距离幂次反比法及全煤层建模法对具有复杂形状特征的矿体进行了数值仿真,以改善其计算精度。对比这3种方法得到的资源储量与原地质报告中的数据,结果表明,普通克里格插值法的资源储量误差仅为0.84%,远低于其他2种方法,其与原地质报告成果的吻合度较高,可以更准确地估算资源储量。

山区高速公路总体路线方案设计与比选

针对山区高速公路沿线建设条件较为复杂,路线方案存在许多复杂和矛盾性因素,本文结合建设交通强国发展需求和辽宁省山区高速公路设计经验,提出“以人为本、绿色公路、品质工程、智慧工程”的项目理念,从地形、地质、可持续发展和经济等角度总结路线方案选线思路,并以赤峰至绥中高速公路(G4515)凌源(蒙辽界)至绥中段项目为依托,对临近自然保护区、煤矿和水库大坝段的线位进行方案设计和比选,确定最优方案,为打造出一条平安、绿色、品质的高速公路奠定基础。

Stability analysis of rib pillars in highwall mining under dynamic and static loads in open‑pit coal mine

The retained coal in the end slope of an open-pit mine can be mined by the highwall mining techniques.However,the instability mechanism of the reserved rib pillar under dynamic loads of mining haul trucks and static loads of the overlying strata is not clear,which restricts the safe and efcient application of highwall mining.In this study,the load-bearing model of the rib pillar in highwall mining was established,the cusp catastrophe theory and the safety coefcient of the rib pillar were considered,and the criterion equations of the rib pillar stability were proposed.Based on the limit equilibrium theory,the limit stress of the rib pillar was analyzed,and the calculation equations of plastic zone width of the rib pillar in highwall mining were obtained.Based on the Winkler foundation beam theory,the elastic foundation beam model composed of the rib pillar and roof under the highwall mining was established,and the calculation equations for the compression of the rib pillar under dynamic and static loads were developed.The results showed that with the increase of the rib pillar width,the total compression of the rib pillar under dynamic and static loads decreases nonlinearly,and the compression of the rib pillar caused by static loads of the overlying strata and trucks has a decisive role.Numerical simulation and theoretical calculation were also performed in this study.In the numerical simulation,the coal seam with a buried depth of 122 m and a thickness of 3 m is mined by highwall mining techniques.According to the established rib pillar instability model of the highwall mining system,it is found that when the mining opening width is 3 m,the reasonable width of the rib pillar is at least 1.3 m,and the safety factor of the rib pillar is 1.3.The numerical simulation results are in good agreement with the results of theoretical calculation,which verifes the feasibility of the theoretical analysis of the rib pillar stability.This research provides a reference for the stability analysis of rib pillars under highwall mining.

Resources of Kaolinite Rocks in China Coal Measures

The proved reserve of kaolinite rocks in China coal measures is about 1.673 billion tons. The types of kaolinite rocks contain tonstein, flintclay and soft kaolin. Their origin modes include alteration of volcanic ash, terrigenous clay deposit and weathering of coal and adjacent rocks. The organic matter and organic acid play an important role in the formation of kaolinite rocks of coal measures. The difference in properties between kaolinite rock and traditional kaolin requires different processing technologies.

Why There Will Be No Peak Coal in the Foreseeable Future

Hard coal and lignite—also referred to here jointly as coal—play a central role in the worldwide supply of humanity with primary energy. As a fossil energy carrier, coal is one of the finite natural resources. The reach of the world’s coal reserves is significant, and coal has the potential to cover some of the global energy and raw-material needs at least into the 22nd century. Precondition for this is a sustainable energy policy, i.e. an equal-ranking view of the goals of environmental and climate compatibility (sustainability), security of supply and competitiveness (affordability). The focus of developments is on resource efficiency and energy savings to obtain more modern and more efficient coal-based power plants. Greater use of coal translates into higher CO2 emissions. So if we are to achieve the climate-protection goals of limiting the rise in temperatures and reducing the CO2 content in the Earth’s atmosphere, the launch of CCS technology is recommended. Within the scope of the climate-protection debate, a discussion is also underway about an alleged drying up of coal availability in the short term (under the heading of “peak coal”). This discussion is an example of how, from the limited perspective of particular interests, a swathe of facts can be ignored. Hence, this article sets out to take a fact-based, sober look at the subject of the “reach of global coal reserves”. How much coal do we really have? And to what extent will coal be available tomorrow to guarantee secure and affordable energy supplies in the future as well? These issues will be investigated here.

“双碳”背景下我国煤炭资源保障能力与勘查方向的思考

我国以煤为主的能源消费结构短期内不会改变。目前我国煤炭能源仍然处在需求量大、资源高强度开发阶段,有必要认真审视我国煤炭资源勘查工作。通过分析我国煤炭资源分布与保存问题,基本摸清了煤炭资源状况。认为我国煤炭资源相对丰富,但分布主要受东西向、南北向“两横”和“两纵”构造带控制,在“九宫”分布不同区域资源赋存与开发程度不均衡,中东部地区开发强度大,西部资源丰富但勘查开发程度低。同时,对我国主要煤炭矿区典型矿井的煤炭资源采出情况进行了调查与计算,研究了煤炭资源回采率的计算方法,得出目前技术条件下多数矿井的煤炭资源回采率在24.3%~59.8%,直接反映了目前开采技术条件下我国查明煤炭资源、储量的实际采出情况。我国目前查明煤炭资源、储量20 a后大多将被开采和占用,保障能力不足,需要引起全社会对煤炭资源勘查工作的重视,提前谋划合理制定针对性的解决方案。从现在开始勘查工作:一是加强中东部老矿区煤炭储量增储勘查力度;二是加快煤炭勘查开发战略西移,建设煤炭基地“双子座”;三是开展深部和复杂地区的地质条件精细勘查评价,助力煤炭资源、储量的储备能力提升,实现煤炭在保障我国能源安全稳定发展中的压舱石作用。

中深埋缓倾斜梯形切眼围岩变形规律及支护技术

针对缓倾斜巷道在开挖扰动、孔隙水压及地应力共同作用下变形破坏的高度复杂性和难以控制的显著特点,以马蹄沟煤矿3506工作面缓倾斜梯形切眼为工程背景,基于弹塑性变形理论,建立了垂直地应力、水平构造应力及孔隙水压共同作用下切眼围岩受力计算模型。考虑开挖过程中切眼围岩内摩擦角与黏聚力的扰动劣化效应,推导了非均匀地应力场作用下切眼围岩的应力和位移解析解,进而针对性地提出了倾斜巷道开挖及其围岩支护方案。结果表明:开挖方式、地质强度、切眼倾角、地应力、孔隙水压及岩体应变软化程度是影响切眼围岩的应力分布与位移大小的关键性因素;倾斜巷道不同断面位置所受地应力和孔隙水压存在差异性,不同掘进区段围岩变形量并不相同,应设计不同的开挖预留量及其支护参数。最后,基于上述理论分析,将马蹄沟煤矿3506工作面缓倾斜切眼分为4个掘进区段,确定了切眼第一区段至第四区段掘进预留变形量分别为300,260,220及200 mm,切眼围岩支护加固后,其顶底板最大移近量为204 mm,两帮最大移近量为165 mm,围岩变形控制效果良好,满足现场生产要求。

基于岩层移动类双曲线模型的水资源“浅保-深储”方法

针对煤炭开采导致地下水位下降和地表植被破坏等生态问题,基于保水采煤的科学内涵和采动覆岩移动类双曲线模型,建立了采动覆岩不同层位含水层“浅保-深储”差异化保护方法。即在上覆岩层破坏损伤最窄的主关键层下离层区注浆控制其上部岩层不破断,保护潜水水位和地表生态;其下部破坏的含水层利用采空区垮落岩体的空隙储存起来,经自净化后再利用。“浅保-深储”模型融合了采空区充填和煤矿地下水库保水的各自优势,并给出其适用的覆岩条件。根据采动覆岩“类双曲线”破坏移动特征,理论推导了主关键层下离层区初次注浆、周期注浆步距以及注采比,分析了注采比受主控参数的影响规律,得知注采比随垮落角和主关键层与煤层间距的增大而减小,随充分采动角和工作面推进距离的增大而增大。采用现场实测注浆数据对理论注采比进行验证,2者基本吻合。采用数值模拟对比分析了覆岩含水层“浅保-深储”、采空区充填保水地下水库的储水效果和煤柱稳定性,获得了采动覆岩移动和地下水流动均具有显著的“类双曲线”特征。基于理论注采比在主关键层下离层区注浆能够实现不同层位含水层“浅保-深储”,且该保水方法煤柱支承压力最大可降低60.8%,显著提高了储水采空区隔水煤柱的安全性,解决了井下采煤与充填难协调问题,利于煤炭绿色、安全、高效开采。

三塘湖-吐哈盆地富油煤赋存特征与资源潜力分析

富油煤是焦油产率≥7%且具备煤、油、气属性的特殊煤炭资源,是煤炭清洁利用的重要资源和开发方向,对缓解国家油气资源紧缺、推动煤化工突破性发展具有重要的科学价值。新疆东部盆地蕴藏着大量富油煤资源,为探明富油煤的赋存特征与分布规律,通过沉积环境分析,结合煤工业分析、元素分析、格金低温干馏测试等手段研究东疆富油煤聚煤规律与赋存特征,采用地质块段法估算富油煤资源量。结果表明:三塘湖盆地富油煤层主要分布于八道湾组上段(J_(1)b^(2))、三工河组(J_(1)s)以及西山窑组下段(J_(2)x^(1))3个层位,焦油产率约13.67%,总体属高油煤;吐哈盆地富油煤发育在西山窑组中段(J_(2)x^(2)),焦油产率约7.6%,总体为含-富油煤。区内富油煤总体特征为特低-中低水分、低-中低灰分、中高-高挥发分,焦油产率高,富含镜质组和壳质组等生油组分,煤化程度低,形成于湖泊-三角洲的沉积环境。研究区富油煤资源潜力大,估算三塘湖盆地2000 m以浅的富油煤资源量约670.83亿t,吐哈盆地2000 m以浅的富油煤资源量约417.55亿t,可采煤层平均厚度达9 m以上。为有效动用富油煤资源,提出煤炭地下干馏的技术设想,即通过石油工程技术在地下煤层建立热量导入和产品产出通道,通过人工加热方式使煤原位发生干馏反应,热解产物包括焦油、煤气(CH_(4)、H_(2)、轻烃C_(2+)等)、水等,煤中的碳元素主要以半焦形式留在地下,产生的二氧化碳可为三塘湖-吐哈盆地的油田提供气驱气源,剩余的二氧化碳可以利用半焦层原位埋存。煤炭地下干馏通过“取氢留碳”实现煤炭资源清洁转化,有望成为富油煤低碳绿色开发的重要技术方向。