The status and development strategy of coalbed methane industry in China

To achieve the goals of carbon peaking and carbon neutrality under the backgrounds of poor resource endowments, weak theoretical basis and other factors, the development of the coalbed methane industry of China faces many bottlenecks and challenges. This paper systematically analyzes the coalbed methane resources, key technologies and progress, exploration effect and production performance in China and abroad. The main problems are summarized as low exploration degree, low technical adaptability, low return on investment and small development scale. This study suggests that the coalbed methane industry in China should follow the “two-step”(short-term and long-term) development strategy. The short-term action before 2030, can be divided into two stages:(1) From the present to 2025, to achieve new breakthroughs in theory and technology, and accomplish the target of annual production of 10 billion cubic meters;(2) From 2025 to 2030, to form the technologies suitable for most geological conditions, further expand the industry scale, and achieve an annual output of 30 billion cubic meters, improving the proportion of coalbed methane in the total natural gas production. The long-term action after 2030 is to gradually realize an annual production of 100 billion cubic meters. The strategic countermeasure to achieve the above goals is to adhere to “technology+management dual wheel drive”, realize the synchronous progress of technology and management, and promote the high-quality development of the coalbed methane industry. Technically, the efforts will focus on fine and effective development of coalbed methane in the medium to shallow layers of mature fields, effective development of coalbed methane in new fields, extensive and beneficial development of deep coalbed methane, three-dimensional comingled development of coalbed methane, applying new technologies such as coalbed methane displacement by carbon dioxide, microwave heating and stimulation technology, ultrasonic stimulation, high-temperature heat injection stimulation, rock breaking by high-energy laser. In terms of management, the efforts will focus on coordinative innovation of resource, technology, talent, policy and investment, with technological innovation as the core, to realize an all-round and integrated management and promote the development of coalbed methane industry at a high level.

A Comprehensive Appraisal on the Characteristics of Coal-Bed Methane Reservoir in Turpan-Hami Basin

The rich coal-bed methane resources in the Turpan-Hami Basin are mainly located in the Shisanjianfang,Hami,Shanshan,Sha'erhu,Kekeya,Kerjian,Aidinghu inclines and the Dananhu coal-bed methane reservoirs. The big-ger coal-bed reservoirs are sitting at a depth of less than 1500 m. The coalbed methane generation,storage and confin-ing conditions of the Turpan-Hami basin can be indicated by eight key parameters. They are coal-bed thickness,coal rank,missing period,permeability,Langmuir volume,rock covering ability,structural confinement and hydrodynamic sealing environment. These parameters constitute a comprehensive appraisal index system of the coal-bed methane res-ervoir characteristics of the Turpan-Hami basin. In these parameters,the missing period of coal-bed methane is indi-cated by a stratum missing intensity factor. It reflects the relative exposure period of coal series. The results of a fuzzy comprehensive judgment showed that the Shisanjianfang coal-bed methane reservoir has the best prospects for exploita-tion and the Sha'erhu,Shanshan,Hami coal-bed methane reservoirs are next in line.

Application of Seismic Anisotropy Caused by Fissures in Coal Seams to the Detection of Coal-bed Methane Reservoirs

Coal-bed methane is accumulated in micro-fissures and cracks in coal seams. The coal seam is the source terrace and reservoir bed of the coal-bed methane (Qian et al., 1996). Anisotropy of coal seams is caused by the existence of fissures. Based on the theory of S wave splitting: an S wave will be divided into two S waves with nearly orthogonal polarization directions when passing through anisotropic media, i.e. the fast S wave with its direction of propagation parallel to that of the fissure and slow S wave with the direction of propagation perpendicular to that of the fissure.

A Pilot-scale Demonstration of Reverse Osmosis Unit for Treatment of Coal-bed Methane Co-produced Water and Its Modeling

This study presents the first demonstration project in China for treatment of coal-bed methane(CBM) co-produced water and recycling.The work aims to provide a research and innovation base for solving the pollution problem of CBM extraction water.The reverse osmosis(RO) unit is applied to the treatment of CBM co-produced water.The results indicate that system operation is stable,the removal efficiency of the total dissolved solids(TDS) is as high as 97.98%,and Fe,Mn,and F-are almost completely removed.There is no suspended solids(SS) detected in the treated water.Furthermore,a model for the RO membrane separation process is developed to describe the quantitative relationship between key physical quantities-membrane length,flow velocity,salt concentration,driving pressure and water recovery rate,and the water recovery restriction equation based on mass balance is developed.This model provides a theoretical support for the RO system design and optimization.The TDS in the CBM co-produced water are removed to meet the "drinking water standards" and "groundwater quality standards" of China and can be used as drinking water,irrigation water,and livestock watering.In addition,the cost for treatment of CBM co-produced water is assessed,and the RO technology is an efficient and cost-effective treatment method to remove pollutants.

Coal-Bed Methane Resource of Mesozoic Basins in Jiamusi Landmass

As a new-replacement of energy resource, coal bed methane is the important gas resource with great strategic significance. There are several number of Mesozoic coal-bearing basins in Jiamusi landmass, eastern Heilongjiang Province. Theresult of the resource assessment revealed that the total resource less than 1 500 m,s depth in the area is about 2 100×108m3. It shows that Jiamusi landmass has great potential of coal-bed gas and is one of the most prospecting districts for developing coal-bed gas in CBM-province Northeast China.

The experiment study on slippage effect of the coal-bed methane transfusion

When the gas flow in the compact porous medium at low speed,it has slippage effect which is caused by the gas molecular collision whit the solidskeleton.Using the gas transfusion slippage effect at researching the coal bed transfusion rule,established the transfusion mathematical model of the coal bed which had considered the slippage effect. Observing the influence of the different toencircle presses,the different hole press and the different actual stress to the coal bed by using the three-axles permeameter.Thus sum- marized the transfusion rule of the coal bed.The experiment indicates that the bigger of the surrounding pressure,the more obvious of the slippage effect.At the same condition of axial pressure and the surrounding pressure,with the increase of the hole pressure,the coal permeability became bigger and then smaller.The coal body effective tress and the permeability curve nearly also has the same change tendency.Thus we can draws the conclusion that the transfusion of the gas in the coal bed generally has the slippage effect.

Dual polarization strategy to enhance CH_(4) uptake in covalent organic frameworks for coal-bed methane purification

The purification of low-grade coal-bed methane is extremely important,but challenging,due to the very similar physical properties of CH_(4)and N2.Herein,we proposed a dual polarization strategy by employing triazine and polyfluoride sites to construct polar pores in COF materials,achieving the efficient separa-tion of CH_(4)from N2.As expected,the dual polarized F-CTF-1 and F-CTF-2 exhibit higher CH_(4)adsorption capacity and CH_(4)/N_(2)selectivity than CTF-1 and CTF-2,respectively.Especially,the CH4 uptake capacity and CH_(4)/N_(2)selectivity of F-CTF-2 is 1.76 and 1.42 times than that of CTF-2.This work not only developed promising COF materials for CH4/N_(2)separation,but also provided important guidance for the separation of other adsorbates with similar properties.

Study on the Logistics Operation of Scale Farm Methane Engineering

Based on the large-scale farms methane project of logistics operation as the breakthrough point, methane project of the supply chain of the raw material supply logistics, production logistics and product sales organization of logistics and operation mode were preliminarily studied, and the methane energy company as the core was decided. The third party logistics as key support for the integration of logistics operation mode provid- ed a new train of thought for the large scale operation and implementation of methane project.

Research regarding coal-bed wellbore stability based on a discrete element model

Wellbore instability is a key problem restricting efficient production of coal-bed methane. In order to perform thorough and systematic research regarding coal-bed wellbore stability problems, a new discrete element model which fully considers the features of cleat coal-beds is established based on the Kirsch equation. With this model, the safe pipe tripping speed, drilling fluid density window and coal- bed collapse/fracture pressure are determined; in addition, the relationships between pipe tripping speed and pipe size, cleat size, etc. and wellbore stability are analyzed in the coal-bed drilling and pipe tripping processes. The case studies show the following results： the wellbore collapses （collapse pressure： 4.33 MPa） or fractures （fracture pressure： 12.7 MPa） in certain directions as a result of swab or surge pressure when the pipe tripping speed is higher than a certain value; the cleat face size has a great influence on wellbore stability, and if the drilling fluid pressure is too low, the wellbore is prone to collapse when the ratio of the face cleat size to butt cleat size is reduced; however, if the drilling fluid pressure is high enough, the butt cleat size has no influence on the wellbore fracture; the factors influencing coal-bed stability include the movement length, pipe size, borehole size.

日本浅表层水合物勘查试采进展

海洋孔隙填充型水合物已得到较广泛资源调查和经过数次试采,与之相比,以赋存于冷泉、泥底辟和泥火山附近的海底表面和近海底沉积物为主的浅表层水合物的勘查试采工作刚刚起步。日本作为最早实施水合物勘查试采的国家之一,自2013财政年以来在浅表层水合物的资源勘查评价、海洋区域地质调查和环境调查、开发技术调研评价、生产系统构建等方面取得了显著进展。基于文献资料调研,概述了日本水合物研发工作的发展历程以及对浅表层水合物研发工作的整体部署,详细介绍了日本在浅表层水合物勘查试采相关领域开展的主要工作,分析认为,日本在如下4方面取得的实际经验和理论认识值得我国浅表层水合物勘查试采体系化部署借鉴参考:以日本海为主的区域性资源和环境调查,以小范围区域为对象的资源量评价示范,以试采场地优选为目标的精细化资源和环境调查,以及“以使用大口径钻头的大范围垂直采掘方法为基础、优先考虑气体举升回收方法和船载分离方法两项关键技术以形成最优组合”的生产系统设计原则的评估确立。

我国“十四五”煤层气勘探开发新进展与前景展望

煤层气开发有助于推动我国早日实现碳达峰碳中和目标。我国煤层气开发已基本实现产业化,但受理论技术等因素制约,发展规模与丰富的资源条件不匹配。“十四五”以来,我国煤层气勘探开发取得5个方面的新进展:一是我国开始进入深层煤层气规模开发新阶段,煤层气产量增速明显加快;二是深层煤层气勘探开发取得重大突破,极大拓展了产业发展空间;三是老气田低效区、薄煤层等难采资源增产改造效果显著;四是与“十三五”期间相比,攻关领域由中—浅层煤层气为主转为以深层煤层气为主,以水平井大规模分段压裂技术为代表的煤层气理论技术在地质认识、钻完井、压裂、排采四大关键环节均取得重大创新,产气效果明显提升;五是煤层气产业发展政策环境持续优化。初步研判,我国深层煤层气资源丰富,埋深大于1500m的煤层气资源量约是1500m以浅的资源量2倍以上;我国已探明煤层气储量以中—浅层为主,但采出程度仅为7%,剩余资源规模可观,而老气田还发育丰富的薄煤层气,已证实是现实接替资源。因此,深层煤层气的重大突破和老气田增产改造的成功成为引领我国煤层气产业加速发展的主要推动力,发展前景良好。在综合多家机构和专家研究结果的基础上,研究认为我国煤层气产量2025年有望达到100×10^(8)m^(3),2035年达到300×10^(8)m^(3)。但我国煤层气快速发展面临着深煤层、薄煤层等新领域煤层气地质理论认识有待深入系统研究,深层煤层气勘探开发工程技术仍处于攻关阶段,产业发展政策支持力度仍有待完善等挑战。因此,建议加强新领域煤层气风险勘探和选区评价、加强高效勘探开发理论技术攻关以及加强煤层气产业政策支持和发展引导。

基于高分五号卫星的山西省煤炭行业甲烷点源排放特征

甲烷是长效温室气体之一,其增温潜势是CO_(2)的28倍,约占全球变暖效应的16%。煤炭生产活动是中国甲烷排放的主要来源之一,作为中国主要的煤炭生产基地之一,山西省煤炭行业排放了大量甲烷。利用高分辨率遥感数据对山西省煤炭行业的甲烷排放进行估算,可以为建立精细化的煤炭行业甲烷排放清单奠定数据基础,并为制定有效的减排措施提供科学依据。利用我国高分五号02星搭载的先进高光谱成像仪(AHSI),使用2021年10月—2023年3月的数据,探测到山西省煤炭行业等408个厂矿的838个甲烷羽流,并计算各羽流的排放速率。结果显示:①山西省煤炭行业的甲烷羽流排放速率呈现出非对称性,84%的羽流的排放速率在0.5~3.0 t/h,但也有少数极端情况,最高的排放速率超过10.0 t/h。②山西省有6个煤炭行业甲烷点源排放密集区,其中5个密集区与XCH_(4)的高值区域相对应。③检测到甲烷排放点源,以煤矿和焦化企业为最多。不同类型的排放源甲烷平均排放速率差异性较大,且排放速率会随时间和排放源的变化而波动。煤炭行业的各个环节都可能存在甲烷排放。④高度持续性排放源虽然只占所有点源的13%,但其贡献了41%的总排放速率。相反,高度间断性排放源虽然占了59%,但其只贡献了25%的总排放速率。全山西煤炭行业的甲烷综合排放速率为177.17±56.35 t/h,主要由煤矿类、焦化类和火电类企业的甲烷排放构成。

基于无人机平台的甲烷监测技术及其在油气行业的应用

对甲烷排放的精准监测是油气行业实现温室气体减排与管控的基础和前提。无人机具有灵活、可操作性强、覆盖范围广、运行成本低等特点,以无人机为飞行平台的甲烷监测技术在油气行业区域甲烷排放监测领域具有巨大的应用潜力。详细阐述了基于无人机平台的甲烷监测技术的优势,梳理了不同的无人机类型,并根据其飞行性能及载荷能力进行了比对,归纳了无人机有效载荷类型、特点及应用场景,总结了国内外无人机甲烷监测技术在油气行业的应用,旨在为基于无人机平台的甲烷监测技术在我国油气行业的应用提供理论和技术参考。

全球甲烷卫星遥感监测技术发展及其对油气行业的影响

在全球绿色低碳转型推动下,各国愈发重视甲烷排放数据的真实性、可靠性和一致性。在欧盟和美国发布的甲烷减排行动计划或战略中,甲烷卫星遥感监测技术应用首次被提升至国家战略高度,而油气行业因其甲烷排放源集中度高、排放强度大、减排潜力突出等特征成为了卫星监测技术首要关注的领域。甲烷卫星遥感监测技术不仅能发现油气生产及运输过程中的大规模甲烷泄漏事故,还能监测到常规作业产生的甲烷泄漏情况,甚至直接追踪地面单一矿井设施的甲烷排放情况,监测精度大幅提升。同时,甲烷排放信息透明度不断提升,或使油气企业因信息不对称而陷入被动局面。建议国家强化对甲烷卫星遥感监测技术的支持力度;推动甲烷遥感监测技术在中国油气行业的应用,促进跨领域合作;建立健全中国油气行业甲烷排放核算、报告与核查(MRV)体系;提升油气企业主动披露甲烷排放信息的意识,进一步提高中国油气企业甲烷减排的力度与水平。

煤与煤层气专业集群建设与思考

打造特色专业集群是地方应用型本科高校转型快速发展的关键,专业集群的组建要结合区域产业链布局、学科基础、产业政策动态及专业人才需求。煤与煤层气专业集群按照“由产业引出的专业集群”模式建群,紧密结合地方产业布局,符合能源革命转型发展需求。下一步建立煤与煤层气现代产业学院,充实集群相关专业设置,加强学科引领,深化合作交流,实现以特色学科、特色专业集群推动特色产业链条创新发展。

煤炭行业甲烷排放控制与环境管理

为加强煤矿甲烷排放管控,梳理了我国煤炭行业甲烷排放与环境管理现状,指出我国煤矿甲烷管控中存在低浓度瓦斯难以利用、监测体系不完善、排放标准缺失、激励性政策不足、关闭煤矿甲烷关注不足等问题。进一步提出强化环评阶段管控、完善监测体系、修订排放标准、完善激励性政策、加快低浓瓦斯利用技术攻关、探索关闭煤矿甲烷减排路径等建议。

我国煤层气产业发展现状研究

近年来,国家重视并大力推进煤层气产业发展,煤矿区煤层气开发技术及装备不断取得突破,煤矿区煤层气开发利用规模持续增长。但煤矿区煤层气开发利用技术及产业发展总体上处于起步阶段,仍然面临煤层气地质条件复杂、开采难度大等现实问题,有必要进一步加强煤层气地质研究,立足科技创新和技术进步,开拓煤层气产业基地建设,促进煤层气体制改革,从而推动煤层气高效开发和利用。因此,本文重点研究煤层气产业发展现状,并根据存在问题提出对应的建议,以期对推进我国煤层气产业的发展提供有益参考。

煤炭行业甲烷排放的影响因素与利用途径

甲烷排放对全球气候变化的影响显著,中国伴生的煤层气储量和开采量居世界前列,因而系统梳理我国煤炭行业甲烷排放现状及其影响因素与利用途径,可为煤炭行业绿色发展和甲烷排放管控提供科学依据与政策建议,对于实现我国碳达峰碳中和目标具有促进作用。概述我国煤层气分布特点,从煤层气资源分布、埋深划分等方面分析我国煤层气的资源特点,总结煤炭行业甲烷排放的微观与宏观影响因素,从微观角度剖析影响甲烷排放的因素,包括底板砂岩厚度、煤层气压力、顶板岩性、开采技术和开采深度等地质条件以及煤炭生产与煤炭品质因素对甲烷保存和排放的影响,并从宏观角度指出煤炭生产量的增加会导致甲烷排放量上升,而能源结构变化尤其新能源替代和严格产业政策实施均有助于降低甲烷排放。从煤层气的提取、净化和利用技术等方面深入探讨甲烷减排的技术途径和可行性,并梳理煤炭甲烷排放趋势,通过综合分析后提出一系列针对煤炭行业甲烷排放的综合管控策略,包括能源结构转型、煤炭消费控制、甲烷减排技术创新和政策推动等,应重视由于煤炭生产结构的变化所引起的甲烷排放变化,加强瓦斯梯级利用技术攻关,提高井下抽采瓦斯利用效率,实现资源的高效利用。应逐步加强对甲烷排放的监测和管理,利用政策约束落实煤炭企业的主体责任,通过实施监测甲烷排放数据,加强宏观视角下甲烷排放的趋势分析,从而为国家政策和法律法规的制定提供支撑依据。