地空时间域电磁系统在陕西神木地区煤矿采空区勘查中的应用

为实现陕西神木地区哈拉沟煤矿周边小煤矿采空区的精确定位,采用地空时间域电磁系统在哈拉沟煤矿三盘区附近原小煤矿可能开采范围开展勘查工作。利用电源车集成的大功率地面发射系统,搭配基于旋翼无人机的单分量地空电磁信号接收系统,共采集23条测线的电磁数据。经数据处理后,得到勘查区内地下视电阻率与视深度的高分辨率成像剖面,结合已知钻孔资料综合分析,推测勘查区对应地下煤层位置的低阻带是由煤层积水采空区造成,据此共圈定了8处疑似积水采空区,其中5处为相对低阻异常区域,分布于勘查区中南部、中部以及东北部区域。本次探测工作验证了地空时间域电磁系统在煤矿采空区勘查中的有效性,能够为工作面合理布置和采空区治理等提供可靠的地质信息。     

地下煤炭气化发电系统运行特性的试验研究

介绍了山东新汶矿业集团在所辖的两个煤矿井进行的地下煤炭气化工艺流程、气化气态产物的主要成分和热值测定结果．地下煤炭气化的气态产物经过净化后,除了供给矿区25000户居民作为家庭用燃料以外,还作为内燃机发电机组的发电燃料,内燃机发电机组的单机额定发电功率为400kW．实际运行结果表明,机组的发电燃料单耗由于燃烧控制系统不能保证燃料充分燃烧造成气缸积炭而增加了15％～20％．为此提出了地下煤炭气化气体产物有效的净化流程,并对发电机组的运行参数、机组出力的影响规律和地下煤炭气化内燃机发电机组的运行特性进行了研究,得出了地下煤炭气化的气态气化产物的收到基低热值在5．72～16．161MJ／Nm^3范围内,气缸正常运行时的壁温范围为370～420℃．地下煤炭气化内燃机发电机组的正常连续运行时间超过4500h,为地下煤炭气化发电机组的推广应用提供了可靠的技术依据．     

倾斜煤层煤炭地下气化模型试验研究

为了认识倾斜煤层煤炭地下气化特征和规律性 ,藉助多功能模型试验台 ,对倾斜煤层进行了模型试验研究 .简述了煤炭地下气化多功能模型试验台结构 .介绍了脉动气化、水蒸汽气化、富氧水蒸汽气化及返流气化方法 ,研究了产出的煤气热值、组份和气化速率 ,并对试验结果进行了讨论与分析 .试验结果表明 ,脉动气化在一定程度上可改善煤气质量 ,采用水蒸汽气化方法 ,能够生产高热值水煤气 ,富氧和返流气化未能明显改善出口煤气质量 ,但能够迅速提高气化炉体的温度 .与急倾斜煤层相比较 ,倾斜煤层尚不能提供有效的渗流燃烧的气化条件 ,因而影响着煤气质量的提高     

煤炭地下气化热爆炸技术模型实验研究

鉴于我国在倾斜、缓倾斜或近水平煤层中进行地下气化所遇到的实际问题,提出了煤炭地下气化热－温控爆破渗流燃烧技术,简述了热爆炸基本原理,介绍了模型试验台结构、爆破参数设计、测试系统及冷态试验,并对试验结果进行了分析。模型试验结果表明,温控爆破松动作用,提供了气固之间有效燃烧气化所需要的大反应表面,并形成渗流燃烧的气化条件,从而证明了将热爆炸－温控爆破技术应用于煤炭地下气化过程的合理性和可靠性。     

不同煤种地下气化特性研究

在地下气化模型试验及理论分析的基础上，研究了不同煤种的地下气化特性．比较了空气连续气化及纯氧．水蒸汽气化条件下的煤气组成，并从气化煤层升温速率、气化速率、煤气产率、气化效率等方面比较了不同煤种的地下气化特性．试验结果表明，煤种的不同组成决定了空气煤气中CO，H2，CH4含量的不同，鼓风量影响着空气煤气的组成．在适宜的汽氧比条件下，不同煤种纯氧，水蒸汽地下气化均可以获得中热值煤气。对于试验煤种，褐煤具有高的气化活性、气化速率及低的煤气产率，其纯氧-水蒸汽气化效率达87％，最适于地下气化；瘦煤地下气化，气化煤层温度上升缓慢，其气化活性较低，气化速率变化平缓，纯氧-水蒸汽气化效率为74％，但气化过程稳定，且具有高的煤气产率，可以进行地下气化；气肥煤煤层升温速率最快，煤气产率仅次于瘦煤，但在煤挥发分析出后，气化速率减小，气化稳定性变差。     

煤炭地下气化过程(火用)分析

将Yong分析引入煤炭地下气化过程分析当中，建立了煤炭地下气化过程Yong分析模型，研究了煤炭地下气化系统的物料及能量转移规律，分析了唐山刘庄煤矿地下气化过程。结果表明，其系统综合Yong效率为85．18%，外供Yong效率为65．66％，不可逆过程Yong损达到14．82％．与地面气化装置相比，地下气化炉综合Yong效率高于高炉和发生炉，低于焦炉，其Yong损主要来自于燃烧不可逆Yong损和传热不可逆Yong损。     

An analysis of new generation coal gasification projects

The global trends of increasing oil and gas costs have compelled coal possessing countries to start long term underground coal gasification (UCG) projects. These enhance national energy security and are among the cleanest, ecologically safest coal utilization technologies. This paper delineates the major characteristics of such technologies and analyzes technical solutions. Highlighting the desire to develop large scale industrial UCG plants, pilot level projects are presented using a new UCG method developed in Russia by Joint Stock Company Gazprom Promgaz. This method is distinct for its high controllability, stability, and energy efficiency. New, efficient technical solutions have been developed over the last 10–15 years and are patented in Russia. They guarantee controllability and stability of UCG gas production. Over one hundred injection and gas production wells have been operated simultaneously.     

初始释放瓦斯膨胀能与煤层瓦斯压力的关系

根据突出模拟实验中出现突出时初始释放瓦斯膨胀能的临界值，可以确定煤层发生突出需要达到的瓦斯压力临界值．本文通过现场钻取煤样，并在试验室进行了不同瓦斯压力下的初始释放瓦斯膨胀能测定，发现煤样的初始释放瓦斯膨胀能与煤中的瓦斯压力呈线性关系．根据这一发现，石门揭煤之前的预排瓦斯过程中，只要用少量的实验就可以确定局部煤层瓦斯压力应该降到多少就可以安全揭开煤层，为石门揭煤进行突出预测和预排瓦斯过程中定量检测其防突效果提供了一种方便可靠的方法.     

Study on primal CO gas generation and emission of coal seam

The main method of casting coal spontaneous combustion is prediction of index gases, with carbon monoxide(CO) commonly used as an index gas. However, coal spontaneous combustion is not the sole source of CO evolution; primal CO is generated through coalification, which can lead to forecasting mistakes. Through theoretical analysis, primal CO generation and emission from coal seams was determined.In this study, six coal samples were analyzed under six different experimental conditions. The results demonstrated the change in coal seam primal gas and concentration as functions of time, different coal samples, occurrence, various gas types and composition concentration, which are in agreement with the previous study on primal CO generation. Air charging impacts on primal gas emission. Analysis of the experimental data with SPSS demonstrates that the relationship between primal CO concentration and time shows a power exponent distribution.     

煤炭地下气化三维非线性动态温度场数值模拟

介绍了煤炭地下气化模型试验条件,通过对气化炉体内燃烧气化煤层温度场分 分析及对边界条件的概化和处理,建立了三维非线性动态温度场数学模型,阐述了模型参数的选取方法。和有限单元方法进行了求解,并对计算结果进行了分析,计算值和实测值的一致性表明对气化炉的煤层介质动态温度场的数值模拟是正确的。从而为进一步对煤炭地下气化过程进行定量研究,提供了必要的理论依据。     

A rapid and accurate direct measurement method of underground coal seam gas content based on dynamic diffusion theory

Coal seam gas content is frequently measured in quantity during underground coal mining operation and coalbed methane (CBM) exploration as a significant basic parameter. Due to the calculation error of lost gas and residual gas in the direct method, the efficiency and accuracy of the current methods are not inadequate to the large area multi-point measurement of coal seam gas content. This paper firstly deduces a simplified theoretical dynamic model for calculating lost gas based on gas dynamic diffusion theory. Secondly, the effects of various factors on gas dynamic diffusion from coal particle are experimentally studied. And sampling procedure of representative coal particle is improved. Thirdly, a new estimation method of residual gas content based on excess adsorption and competitive adsorption theory is proposed. The results showed that the maximum error of calculating the losing gas content by using the new simplified model is only 4%. Considering the influence of particle size on gas diffusion law, the particle size of the collected coal sample is below 0.25 mm, which improves the measurement speed and reflects the safety representativeness of the sample. The determination time of gas content reduced from 36 to 3 h/piece. Moreover, the absolute error is 0.15–0.50 m³/t, and the relative error is within 5%. A new engineering method for determining the coal seam gas content is developed according to the above research.     

Law of gas production during coal heating oxidation

Coal spontaneous combustion is a great threat to mine safety, and gas is the key index to describe coal spontaneous combustion. Taking the coal samples of different kinds of coal as research object, the temperature programmed oxidation experiment was carried out, and the gases produced by coal samples at different temperatures were collected and analyzed by gas chromatography. This research studied the variation characteristics of gas species and gas concentrations in different coal samples during heating oxidation. The experimental results show that different coal samples produce different kinds of gases in the process of heating and oxidation. The order of gas production is CO, C_2H_6, C_2H_4, C_3H_8, and the relationship between gas production and temperature is approximately exponential. With the increase of coal metamorphic degree, the turning point temperature of sharp rise in coal sample gas production rate become higher, the oxidation ability of coal sample decreases, and the quantity of gas production decreases during the same time period.     

Analysis of Physical and Chemical Characteristics and Influence Factors of UCG

Based on the UCG (underground coal gasification) theory, the “three zones“ which are oxidization zone,reduction zone, and drying zone, were divided; physical and chemical properties of each zone were analyzed. Factors, such as temperature, rate of water pouring, quanzity of air blast, thickness of coal seam, and the operation pressure were discussed. Among the influencing factors, the temperature is the most important one.     

瞬变电磁法探测煤炭地下气化燃空区扩展的试验研究

煤炭地下气化技术抛弃了全部庞大的、笨重的采煤设备与地面气化设备,并将传统的地面气化转化为地下有控制的气化新技术,具有安全性好、投资少、效率高、污染小、效益高等优点。在地下气化过程中,由于燃空区空间不断扩大影响炉内温度,同时引起燃控区上方煤岩层的过量移动和地表沉陷。如何监测气化过程中燃空区塌落空间的变化,对控制气化过程反应、炉内温度的稳定、燃空区上覆岩层塌落及地表沉陷起着至关重要的作用。本文提出采用瞬变电磁法(TEM)对急倾斜煤层中煤炭地下气化燃空区进行探测。现场试验研究表明,该方法能够较好地探测燃空区扩展范围。     

水绿矾对阳泉5矿无烟煤自燃特性的影响

在讨论水绿矾物理，化学性质的基础上，利用差示扫描量热（DSC）技术，对阳泉5矿煤样及其所含水绿矾在实验室进行了实验，结果表明，煤中所含的水绿矾暴露于空气中时将会产生大量热量。对煤自燃产生促进作用，且含量越高。影响越大。     

矿井直流电法及在煤层底板突水探测中的应用

阐述了矿井直流电法及其在探测煤层底板突水中的应用．由于受全空间效应和巷道空间影响，井下稳恒电流场的分布有其特殊性．文中重点叙述了不同矿井直流电法的全空间效应和巷道影响特征，给出了拟一维层状介质模型的巷道影响校正系数公式．结合应用实例，对巷道底板电测深法、矿井电剖面法和高密度电阻率法资料的处理与解释方法分别进行了讨论．     

测井曲线在红四井田煤岩层对比中的应用

红四井田含煤地层为二叠系下统山西组和石炭二叠系太原组,编号煤层12层,通过对该区视电阻率（三侧向电阻率曲线）、自然伽马曲线、伽马曲线的形态及组合规律的分析,并综合对比了该井田的煤岩层可知,5-1煤层上部中粗砂岩砂体、9-1煤层顶板的石灰岩在测井曲线上的特殊特征可分别作为5煤层和9煤层的主要判别依据,同时5煤层至8煤层的组合特征在本区也是唯一的.红四井田测井曲线的实例对比表明,在该井田利用测井曲线可有效地进行煤岩层变化规律的对比研究及层位划分.     

Groundwater Pollution from Underground Coal Gasification

In situ coal gasification poses a potential environmental risk to groundwater pollution although it depends mainly on local hydrogeological conditions.In our investigation, the possible processes of groundwater pollution originating from underground coal gasification (UCG) were analyzed.Typical pollutants were identified and pollution control measures are proposed.Groundwater pollution is caused by the diffusion and penetration of contaminants generated by underground gasification processes towards surrounding strata and the possible leaching of underground residue by natural groundwater flow after gasification.Typical organic pollutants include phenols, benzene, minor components such as PAHs and heterocyclics.Inorganic pollutants involve cations and anions.The natural groundwater flow after gasification through the seam is attributable to the migration of contaminants, which can be predicted by mathematical modeling.The extent and concentration of the groundwater pollution plume depend primarily on groundwater flow velocity, the degree of dispersion and the adsorption and reactions of the various contaminants.The adsorption function of coal and surrounding strata make a big contribution to the decrease of the contaminants over time and with the distance from the burn cavity.Possible pollution control measures regarding UCG include identifying a permanently, unsuitable zone, setting a hydraulic barrier and pumping contaminated water out for surface disposal.Mitigation measures during gasification processes and groundwater remediation after gasification are also proposed.     

煤层底板破坏带电阻率法异常特征研究

我国大约60％的煤矿不同程度受到奥灰水的影响,研究承压水上采煤引起的底板破坏规律对于煤矿安全开采具有十分重要的意义。本文对电阻率法探测井下底板破坏带视电阻率异常特征进行研究。应用商业电法正反演软件EarthImager3D设计工作面推进过程中底板破坏带地质模型,利用混合边界条件下有限差分法进行正演模拟,并分析其异常特征和分布规律。正演结果表明,电阻率法能探测出底板破坏带异常,随着工作面的推进,在视电阻率剖面图上异常体的位置出现相应的移动。     

Spontaneous combustion liability between coal seams: A thermogravimetric study

The spontaneous combustion liability of coal can be determined by using different experimental techniques. These techniques are well-known in their application, but no certain test method has become a standard to prove the reliability of all of them. A general characterisation which included proximate and ultimate analyses, petrographic properties and spontaneous combustion tests(thermogravimetric analysis(TGA) and the Wits-Ehac tests) were conducted on fourteen coal and four coal-shale samples.The spontaneous combustion liability of these samples collected between coal seams(above and below)were predicted using the TGA and the Wits-Ehac tests. Six different heating rates(3, 6, 9, 15, 20 and 25 °C/min) were selected based on the deviation coefficient to obtain different derivative slopes and a liability index termed the TG_(spc) index. This study found that coal and coal-shale undergo spontaneous combustion between coal seams when exposed to oxygen in the air. Their intrinsic properties and proneness towards spontaneous combustion differ considerably from one seam to the other. The Wits-Ehac test results agreed with the TG_(spc) results to a certain extent and revealed the incidents of spontaneous combustion in the coal mines.