Study on the driving factors and regulation mode for coal production capacity

Coal production capacity regulation is a complex system involving economic growth,structural optimization,high-efficiency mining,and environmental protection.Based on its driving factors,this paper forms four regulation modes representing different control orientations,establishes a system dynamics model,and predicts the regulation effects of single-factor and combined control mode.The result shows:(1) Except for the mechanization degree and recovery rate,the other nine individual production capacity control policies are all conducive to reducing coal production capacity and restraining the excessive growth of coal production capacity.(2) The effect of combined regulation mode on slowing down the growth of coal demand,regulating the excessive growth of coal production capacity and new capacity investment are obviously better than that of single policy.(3) The combined control modes have obvious differences in the suppression effect on coal production capacity:transformational development mode > technology-driven mode > structural optimization mode > efficiency improvement mode.Therefore,in the process of achieving optimal regulation of coal production capacity,attention should be paid to the preferential use of transformational development and technology-driven mode.At the same time,the comprehensive use of regulation and control methods should also be considered to improve the regulation effect and the regulation efficiency of coal production capacity.

Coal Production and Consumption in China

China has rich coal deposits. According to statistics, the calculated deposits of coal in China are 4.4927 trillion tons, including 2.6704 trillion tons within the shallow depth of 1,000m under ground. Up to the end of 1991, the proven deposits were 1.0033 trillion tons and the guaranteed deposits were 983.3 billion tons. The coal formed in China covers many periods. It spreads widely with complicated types,

Forecasting on Indonesian Coal Production and Future Extraction Cost: A Tool for Formulating Policy on Coal Marketing

Since 2011 Indonesia has become the world’s largest exporter of steam coal. Two supporting factors of Indonesia to be the largest exporter are its enormous production and low operating cost. This paper foresees the production and extraction cost of Indonesian coal in the coming period to evaluate marketing policies and estimate the cost of Indonesian coal supply in domestic market as well as in export market. The production forecasting is carried out by Gompertz curve. Peak production of Indonesian coal is expected to take place in 2026. Moreover, the extraction cost in coal basins which produce high calorific value of coal, in accordance to the operating cost forecasting, is higher than the one with low calorific value of coal due to its higher stripping ratio. Three main basins of Central Sumatra, Tarakan, and Barito basins play major rule in supplying coal for domestic use in short term. And other coal basins such as South Sumatra, Kutai, Bengkulu, and Ombilin basins provide long term supply in the domestic and export markets.

Safety diagnosis on coal mine production system based on fuzzy logic inference

According to the randomness and uncertainty of information in the safety diagnosis of coal mine production system (CMPS), a novel safety diagnosis method was proposed by applying fuzzy logic inference method, which consists of safety diagnosis fuzzifier, defuzzifier, fuzzy rules base and inference engine. Through the safety diagnosis on coal mine roadway rail transportation system, the result shows that the unsafe probability is about 0.5 influenced by no speed reduction and over quick turnout on roadway, which is the most possible reason leading to the accident of roadway rail transportation system.

Coal mine safety production forewarning based on improved BP neural network

Firstly,the early warning index system of coal mine safety production was given from four aspects as personnel,environment,equipment and management.Then,improvement measures which are additional momentum method,adaptive learning rate,particle swarm optimization algorithm,variable weight method and asynchronous learning factor,are used to optimize BP neural network models.Further,the models are applied to a comparative study on coal mine safety warning instance.Results show that the identification precision of MPSO-BP network model is higher than GBP and PSO-BP model,and MPSOBP model can not only effectively reduce the possibility of the network falling into a local minimum point,but also has fast convergence and high precision,which will provide the scientific basis for the forewarning management of coal mine safety production.

Evaluation of gas production from multiple coal seams： A simulation study and economics

Gas production from multiple coal seams has become common practice in many coal basins around the world. Although gas production rates are typically enhanced, the economic viability of such practice is not well studied. In order to investigate the technical and economic feasibility of multiple coal seams production, reservoir simulation integrated with economics modelling was performed to study the effect of important reservoir properties of the secondary coal seam on production and economic performance using both vertical and horizontal wells. The results demonstrated that multiple seam gas production of using both vertical and horizontal wells have competitive advantage over single layer production under most scenarios. Gas content and permeability of the secondary coal seam are the most important reservoir properties that have impact on the economic feasibility of multiple seam gas production. The comparison of vertical well and horizontal well performance showed that horizontal well is more economically attractive for both single well and gas field. Moreover, wellhead price is the most sensitive to the economic performance, followed by operating costs and government subsidy. Although the results of reservoir simulation combined with economic analysis are subject to assumptions, multiple seam gas production is more likely to maintain profitability compared with single layer production.

Integral evaluation of operating quality and the deciding of management strategy in productive coal mines

According to overall mean square root of weighted deviation, presented an evaluation model of geology-technique-social conditions with a significant index system for the estimation of operating quality in productive coal mines. In the given example, the evaluation result is used to decide management strategy of coal mine, which plays a guiding role in the production.

Distributions of rare-earth elements in two Chinese coals and their burnt products

The concentrations of two fresh Chinese coals (lignitie and fatty coal ) from dif-ferent geological origin and the corresponding fly and bottom ashes were determined us-ing inductively coupled plasma mass spectrometry(ICP-MS). The ranges and means of concentrations of these elemennts were given. Based on the combustion simulating ex-periment in the one-dismensional boiler, the contents of REE (rare-earth element) of 18 samples in lignite, fatty coal and their fly and bottom ashes in different combustion condi-tion were determined, and geochemical feature of REE were analyzed.

煤炭工业数字智能绿色三化协同模式与新质生产力建设路径

煤炭工业是支撑我国经济社会高速发展和保障国家能源安全的压舱石与稳定器,承担着能源保供与支撑新能源稳定发展的时代使命,煤炭工业的高质量发展既是落实我国能源安全新战略与产业体系变革的关键,也是推进能源产业可持续发展与促进国家高质量发展的基础。当前我国煤炭工业高质量发展已取得阶段成效,能源保供成绩显著,产业结构不断优化,科技创新能力显著提高,绿色开发与清洁高效利用持续推进。但当前煤炭工业仍面临诸多挑战,发展水平与中国式现代化的国家需求差距较大,可持续发展受多重因素制约,数字技术与煤炭开发利用尚未深度融合,智能化建设仍处于示范培育阶段,绿色化发展不平衡且矛盾突出,煤炭工业的转型升级仍然任重道远。结合当前煤炭工业发展现状与挑战,提出了数字化、智能化、绿色化(三化)协同的发展模式,明确了煤炭新质生产力的核心内涵,构建了三化协同发展煤炭新质生产力的总体架构,阐述了通过数字化变革生产要素创新配置、智能化引领关键技术跨越突破、绿色化主导传统产业深度转型三大要素催生煤炭新质生产力的技术路径,提出了六大技术体系:通过研发全产业链数据高效采集与深度治理技术体系,打通煤炭产—运—储—销—用全流程的数据壁垒;通过研发构建煤炭行业知识图谱与智能决策管控技术体系,深度挖掘煤炭产业上下游各业务场景的关联关系与价值,为煤炭生产利用全流程的自主决策与智能控制奠定基础;开展煤炭资源智能-绿色-高效开发技术体系、煤炭产业安全协同保障技术体系、矿区生态智能监测-预警-修复技术体系、煤炭柔性开发与清洁低碳利用技术体系研究,实现煤炭开发利用全产业链、全流程的三化协同发展,培育形成煤炭新质生产力,为煤炭工业的整体形象带来根本性变革提升。

Empirical Analysis of Gross Domestic Product and Coal Import Based on VAR Model

The speed of China’s economic development is gradually accelerating, and the demand for energy is also constantly increasing, especially the demand for coal. In order to reveal whether the coal imports have an impact on China’s economic development, this paper constructs the VAR(6) model by selecting the quarterly data of coal imports (CIV) and gross domestic product (GDP) from 2002 to 2017, performing ADF (Augmented Dickey-Fuller) stationarity test and Johansen cointegration test. It shows that there is a long-term stable equilibrium relationship between coal imports and GDP. Then the impulse response function is used to obtain the relationship between coal imports and GDP. It is found that the impact of coal imports on GDP is greater than the impact of GDP on coal imports.

Graded coal-its role in iron casting production from greensand systems

Coal has often been regarded as a problem additive to solve and improve the surface finish of iron castings,but at the same time causes other issues such as increased loss on ignition,total fines and moisture in system sands.Although many altermatives have been tried,there is no real substitute for thw all round properties of this wonderful natural resource.With the correct choice of coal,the combination of low ash,high volatile and swell index properties coupled with the key element of grading size,ensures castings are produced free from metal penetration and surface related problems.By careful selection,safe handling and processing coal continues to offer a good simple cost effective solution.Coal is subject to regulations in storage,processing and transportation and then further subjected to safe handling and use by the foundry.Despite these handicaps,it is still economical to the end user and modern processing and grading methods ensure it is used in the optimum condition to help produce quality castings.

寿阳区块煤层气井产粉特征与煤体结构相关性研究

针对沁水盆地寿阳区块煤层气井产粉严重的问题,连续采集井口煤粉溶液样品,在实验室测试获取了煤粉浓度、煤粉粒径和煤粉形态等煤粉产出特征。通过测井曲线和构造曲率判识了煤体结构特征,利用数据描述分析和Pearson相关系数计算方法定量分析了产粉特征与煤体结构相关性。研究成果为寿阳区块煤层气产粉规律研究和控粉措施提供了实验数据和理论指导。

Influence of depressurization rate on gas production capacity of high-rank coal in the south of Qinshui Basin, China

A desorption simulation experiment with the condition of simulated strata was designed. The experiment, under different depressurizing rates and the same fluid saturation, was conducted on the sample from 3# coal of Daning coal mine in Jincheng, Shanxi Province. The gas production rate and pressure change at both ends of the sample were studied systematically, and the mechanisms of some phenomena in the experiment were discussed. The experimental results show that, whether at fast or slow depressurizing rate, the methane adsorbed to high-rank coal can effectively desorb and the desorption efficiency can reach above 90%. There is an obvious inflection point on the gas yield curve during the desorption process and it appears after the pressure on the lump of coal reduces below the desorption pressure. The desorption of methane from high-rank coal is mainly driven by differential pressure, and high pressure difference is conducive to fast desorption. In the scenario of fast depressurization, the desorption inflection appears earlier and the gas production rate in the stage of rapid desorption is higher. It is experimentally concluded that the originally recognized strategy of long-term slow CBM production is doubtful and the economic benefit of CBM exploitation from high-rank coal can be effectively improved by rapid drainage and pressure reduction. The field experiment results in pilot blocks of Fanzhuang and Zhengzhuang show that by increasing the drainage depressurization rate, the peak production of gas well would increase greatly, the time of gas well to reach the economic production shortened, the average time for a gas well to reach expected production reduced by half, and the peak gas production is higher.

煤矿生产区周边水体环境重金属污染分析与治理技术

水体环境受污染会严重影响生态平衡,利用物理化学技术与生物治理技术相结合的方式,治理煤矿生产区水体环境重金属污染。在分析重金属污染情况后,考虑到重金属污染物进入水体后会出现降解、沉淀、氧化以及吸附反应,根据水体环境实时变化特征,利用物理与化学治理技术实施过滤、物理吸附、土壤淋漓以及化学固化操作。同时,利用水中微生物种群,通过生物治理的方式,消纳、转移重金属污染物。实验结果表明,该技术对水中的锰、铁以及铬等重金属元素均能高效地治理、去除。

电解煤浆制氢过程中煤阶及矿物的影响与煤结构演化研究进展

电解煤浆制氢(CSE)是一种在温和条件下实现电化学制氢与煤炭低碳清洁利用的新技术。电解煤浆制氢的理论分解电压仅为0.21V,实际消耗的能量约为电解水制氢的1/3~1/2,具有能耗低、污染小,可与煤基精细化学品制备、煤岩显微组分分离等过程集成的优点,但煤转化率低、煤浆电解机理不清晰等问题仍具有极大挑战性。本文讨论了CSE机理研究现状,概述了煤阶及矿物质对CSE的电氧化活性的影响,总结了CSE过程中煤表面元素、官能团结构、煤碳骨架结构在阳极区电化学氧化的变化规律,讨论了阴极区电化学还原对煤表面润湿性、Zeta电位等煤表面性质的影响,以及阴极区添加煤浆的电还原制氢及其耦合技术,以期为CSE制氢与煤低碳清洁利用提供理论支撑。此外,本文还展望了CSE的发展方向,提出了高性能CSE电极催化材料开发及煤氧化-还原反应调控机理研究是该技术获得突破的关键。

不同CO_(2)压力下黄铁矿与煤制气耦合机制研究

目的为了研究不同CO_(2)压力下黄铁矿与煤制气的耦合机制,方法利用压力为1,3,5 MPa的高压罐进行煤和黄铁矿厌氧发酵产气试验。结果结果表明:(1)压力1 MPa时产气量较好,最终产气量为1.26 mmol/g;压力增加,罐中产气量减少,压力5 MPa时产气量仅0.02 mmol/g。(2)随着压力增加,水溶液中HCO-3质量浓度和氧化还原电位(Eh)逐渐上升,pH逐渐下降,5 MPa试验组反应末期pH最低,为4.02,1 MPa压力罐内总铁有消耗,波动较大;反应前期,3,5 MPa压力罐中总铁质量浓度持续增加,说明反应前期3,5 MPa压力下黄铁矿溶解量增加较多;(3)高压条件下,化学需氧量(chemical oxygen deman,COD)和短链脂肪酸浓度水平的显著减少反映了厌氧发酵程度的减弱和黄铁矿酸化程度的增强;(4)压力增加,功能菌种丰度和多样性降低,硫杆菌属逐渐处于优势地位,厌氧发酵过程基本停滞。结论适宜的CO_(2)压力条件可促进煤储层条件下的微生物生长代谢,同时添加黄铁矿发生氧化产生的铁离子,可促进菌群酶活,使煤生物产气反应顺利进行。研究结果可为原位条件富集营养液注入后的产气机制研究提供理论支撑。

基于蒙特卡罗方法的煤矿爆破作业风险评估

为量化分析煤矿爆破作业各作业步骤造成的风险以及全面客观地对其进行风险评估,借助蒙特卡罗方法建立煤矿爆破作业步骤风险评估模型,对作业流程的行为风险后果值进行累积概率分布,最终依据蒙特卡罗方法模拟的均值结果和作业流程总体风险结果判定各作业步骤的风险大小和风险等级,并提出控制此类不安全行为发生的措施。结果表明:爆破作业流程风险大小顺序依次为清退物品入库、装药、连线、警戒、起爆后安全检查、领取并检查爆破物品、起爆、运送爆破物品、接受爆破任务、作业前安全检查、起爆前安全检查、封孔。