Utilization Of Coal Mine Methane Research Articles

Coal mine methane utilization as a component of the complex mining concept in the context of conversion into thermal and electrical energy

The paper deals with multi-component complex mining of mineral raw materials in the context of sustainable development and its important component – coal mine methane utilization and its conversion into thermal and electrical energy. The conducted analysis of scientific and practical experience has shown the multi-parameter nature of this process and the influence of a large number of factors. The mining-geological conditions of the Western Donbas (Ukraine) are substantiated as the research object, which makes it possible to limit the variation of geomechanical factors, as well as to develop basic provisions and general principles for reasoning predictive assessments of outgassing during complete mining of coal reserves. The dependence of gas volume on specific gas content of lithotypes and the volume of their destruction related to the coal-bearing stratum shear mechanisms at different options of complete mining of the Western Donbas coal reserves, is presented. The patterns of influence of the main geomechanical factors on the propagation of disturbed rock zones are substantiated.

How efficient coal mine methane control can benefit carbon-neutral target: Evidence from China

Coal is expected to remain the primary energy source in China for the foreseeable future. Utilizing the methane released during the mining process through effective coal mine methane (CMM) control technologies can provide triple benefits in terms of safety, energy, and the environment, thus contributing to carbon neutrality goals. However, few studies evaluated the status and benefits of CMM control. In this study, we quantify emissions, statistical extraction, and utilization of CMM to evaluate the current status of CMM control in China. Gas accidents, avoided coal consumption, greenhouse gas (GHG) emission reductions, and carbon trading revenues were used as indicators to assess the contribution of CMM controls to China's carbon neutrality goals. The results show that a total amount of 22.86 Tg methane was generated in 2020, of which 7.26 Tg was extracted, and out of that extracted amount, 5.46 Tg of methane was effectively utilized. Since 2005, CMM control has effectively ensured the safe production of coal mines, and the CMM utilized can replace 53.21 million tons of standard coal consumption and reduce GHG emissions by 958.55 TgCO2e. Furthermore, if methane were strategically included in carbon trading markets, it could generate 52.26 billion CNY in revenue. This research provides valuable scientific guidance for CMM control, CBM development project benefit assessment, and policymaking in China.

Feasibility study of using cogeneration plants at Kuzbass coal mines

The paper considers the problem of reducing greenhouse gas emissions in the process of coal mining during the coal mine methane utilization in power supply systems. An algorithm to form recommendations for the implementation of CMM generation is presented. A simulation model for one of the Kuzbass coal mines was developed in the PowerFactory software application. The simulation model considers the uneven nature of the power consumption of mining equipment. As a result of modeling, daily power consumption profiles and voltage levels in the coal mine power supply system were determined before and after the implementation of the proposed measures. Based on the results, the technical and economic effects was estimated, which consisted in reducing the direct and indirect carbon footprint, electricity and capacity fees. It has been established that the cost of carbon dioxide emission quotas significantly affects the investment attractiveness of cogeneration projects. Based on the results, recommendations are given to stimulate the development of small generation in coal mines.

Decreasing methane emissions from China’s coal mining with rebounded coal production

China is the world’s largest anthropogenic methane (CH4) emitter, with coal mine methane (CMM) as one of the main contributors. However, previous studies have not reach consensus on the magnitude and trend of China’s CMM emissions since 2010. Through distribution fitting and Monte Carlo methods, dynamic emission factors (EFs) of CMM at the province-level were derived with high confidence; along with the updated data on surface mining, abandoned coal mines, and methane utilization, we revealed that China’s annual CMM emissions were estimated at 20.11 Tg between 2010 and 2019 with a decline of 0.93 Tg yr−1. Although coal production was revived in 2017, we found that the growing trend of China’s CMM emissions since 2012 were curbed by the previously-overlooked factors including the growth of CMM utilization and coal production from surface mining, and decrease of EFs driven by the closure of high CH4-content coal mines and a regional production shift to lower-emission areas.

Assessment of coal mine methane (CMM) and abandoned mine methane (AMM) resource potential of longwall mine panels: Example from Northern Appalachian Basin, USA

Coal mine methane (CMM) and abandoned mine methane (AMM) are by-products of underground mining of gassy coal beds. The quantity and the emission rate of CMM and AMM may vary depending on the type of mine, gas content of the mined coal bed, and gas sourced from strata and coal beds in overlying and underlying formations affected by mining. Therefore, if a mine has the potential of accumulating gas after being abandoned and sealed properly, that methane may be produced and used as an energy source to serve local communities in the area. Producing AMM also prevents methane, which is a potent greenhouse gas, from leaking to the atmosphere through seals, shaft plugs or surface cracks.A technical barrier to economical utilization of CMM and AMM is the uncertainty about how much methane may be available in the gas emission zone (GEZ) as a resource during mining, as well as after the panels are sealed and the mine is abandoned. Another difficulty is estimating how much of the potential methane resource can be produced from gob gas ventholes (GGV) converted to capture AMM.In this study, a comparative assessment is presented to address the issues stated above. The assessment was conducted on two adjacent panels of a longwall mine that operated in Pennsylvania until 2016 in the Northern Appalachian Basin. The study is based on two approaches that might be used depending on the availability of data. The first approach uses an extensive geological data set, geostatistics, and measured shaft gas emission and GGV production values that were collected while the panel (s) were active to assess the AMM resource. The second approach uses a minimal amount of geologic data, uncertainty of the data as probabilistic distributions, and the use of publicly available software to predict during-mining emissions. Results showed that both approaches provide relatively comparable estimates of AMM resources and AMM recovery potential using wellbores. The differences in assessed quantities are mostly due to the characteristics of the two methods. In that regard, this paper can be considered as guidance to choose the assessment approach based on data availability.

Design and economic evaluation of low concentration methane (CMM) regenerative thermal oxidation heating system

Based on the pursuit of coal mine methane (CMM) emission reduction, CMM utilization and the tendency of heating system in the coal mine sites, a design of the low concentration CMM regenerative oxidation technology (RTO) specified in a coal mine was introduced. The design method of the technology was carried out in detail, and the low concentration CMM regenerative oxidation heating system replacing traditional heating by coal-fired boiler in coal mines was compared technically and economically, including method of “Incremental return on investment” and corrected-cost method. In addition, the application of low concentration technology was prospected. And it would give a great contribution to the design and project promotion in this area.

Quantifying the benefits of coal mine methane recovery and use projects: Case study on the application of in-mine horizontal pre-drainage boreholes at gassy coal mines in India and the optimization of drainage system design using reservoir simulation

Abstract This article aims to illustrate, through the presentation of case studies, the application of coal mine methane (CMM) drainage technology at two gassy coal mines in India, and to quantify the associated economic and environmental benefits. This work, which is based on two studies developed by the U.S. Environmental Protection Agency (USEPA) through the Global Methane Initiative (GMI), demonstrates that the use of in-mine horizontal boreholes for pre-drainage, capture, and utilization of CMM is both technically and economically feasible. Furthermore, the results show reservoir simulation is a useful tool for optimizing in-mine horizontal pre-drainage borehole placement. The future development and implementation of CMM drainage at each mine has the potential to lower or offset electricity costs, reduce greenhouse gas emissions, unlock coal reserves, and improve mine safety and energy security.

ОБЗОР ТЕХНОЛОГИЙ И ПРАКТИКИ УТИЛИЗАЦИИ ШАХТНОГО МЕТАНА В РОССИИ И ЗА РУБЕЖОМ

ОБЗОР ТЕХНОЛОГИЙ И ПРАКТИКИ УТИЛИЗАЦИИ ШАХТНОГО МЕТАНА В РОССИИ И ЗА РУБЕЖОМ

Seismological Survey of the Coal Fields Based on the Applying of the Low-Power Sources of Oscillation

the application of seismoacoustic profiling by the method of a common depth point (CDP) to clarify the geological conditions of the coal fields, to determine the location and extent of the existing faults is considered. The results of measurements made in the Kuznetsk Coal Basin (Kuzbass) on the basis of the use of longitudinal and shear elastic waves generated by a source of low power oscillations are presented. The field measurements have been made on the two surface geophysical profiles with the total length of 1048 m. The proposed approach allowed reaching the depth of the transverse waves distribution at the level of 300 meters and can be effectively used as complementary to other studies in determining the filtration properties and permeability of coal seams with the aim of developing measures for their degassing and subsequent utilization of coalmine methane.

A strategic approach to selecting policy mechanisms for addressing coal mine methane emissions: A case study on Kazakhstan

Coal production globally is projected to grow in the foreseeable future. Countries with heavy reliance on coal could reduce methane and other emissions through the capture and utilization of coal mine methane (CMM) in the short and medium term, while they pursue structural and long-term economic changes. Several countries have successfully implemented policies to promote CMM capture and utilization; however, some countries still struggle to implement projects. This paper outlines key factors to consider in adapting policies for CMM mitigation. The authors propose an approach for selecting adequate mechanisms for stimulating CMM mitigation that involves reviewing global best practices and categorizing them functionally either as mechanisms needed to improve the underlying conditions or as CMM-specific policies. It is important to understand local policy frameworks and to consider whether it is more feasible to improve underlying policy conditions or to provide targeted incentives as an interim measure.Using Kazakhstan as a case study, the authors demonstrate how policymakers could assess the overall policy framework to find the most promising options to facilitate CMM projects. Kazakhstan’s emissions from underground coal mines have been increasing both in total and per tonne of coal production, while overall production has been declining. CMM mitigation presents an opportunity for the country to reduce its greenhouse gas emissions in the near and medium term, while the government pursues sustainable development goals. Analysis shows that policymakers in Kazakhstan can leverage existing policies to stimulate utilization by extending feed-in tariffs to cover CMM and by developing working methodologies for companies to obtain emission reduction credits from CMM projects.

Pathways to Shrink CO2 Emissions in China's Coal Industry

While coal fueling China's economic growth it has already been causing severe pollution and amounts of CO 2 emission. How to make deep reductions in carbon emission is not only a huge challenge for the greatest consumer of coal, but also a revolution for China’s coal industry. The paper explores how to shrink CO 2 emissions during the lifetime of coal. The paper points out that increase of coal mine efficiency and productivity, green mining, utilization of coal mine methane and environment-friendly disposal of coal gangue can reduce CO 2 during coal mining; coal preparation and coal by wire can decrease CO 2 during coal preparation and transportation; improving combustion efficiency, CO 2 capture and storage (CCS) and coal transformation can lessen CO 2 during coal utilization. The paper also points out that Circular Economy Park is a practical way to develop a low carbon economy for coal industry. An econometric model for total coal industry and each sector are constructed to measure carbon emissions based on CO 2 equivalent emissions, then with detailed calculations, based on potential greenhouse-gas emission's reduction, a most likely low carbon roadmap of China's coal industry is depicted with scenario analysis method.

Utilization prospects for coal mine methane (CMM) in Kuzbass

Coal mine methane (CMM) is a considerable, relatively unused, resource in Russia. With the second largest proven coal reserves in the world, behind the USA, Russia has a tremendous coalbed methane (CBM) resource. The coal mine methane (CMM) emissions which are created from the CBM resource by way of coal mining yield a significant fraction of the anthropogenic greenhouse gas emissions in the country. Developing CMM utilization projects will mitigate at least some of these emissions. Having evaluated the CMM resources at various underground coal mines in Kuzbass, it has been determined that it is economically viable to apply a variety of CMM utilization technologies in Russia. CMM use for electricity production was found to be quite capital intensive. Although economically viable, this option was the least attractive of the four technologies which were considered. Thermal energy production from boilers and delivering liquefied CMM at vehicle fueling stations were of intermediate potential. The most attractive option is the fueling of vehicles with compressed CMM. This required the lowest capital investment and had the highest paybacks, including a very rapid 2 ½ year payback.

Deep Coal Mine Methane Drainage in China with Lower Greenhouse Gas Emissions: Insights of Borehole Protection Technology

Climate warming has currently been one of the most important global environmental issues. Coal mine methane (CMM) is a typical greenhouse gas with higher global warming potential and ozone depletion potential than CO2. Unfortunately, it should be noted that the CMM emission increases rapidly with the increasing coal consumption in China. Fast and whole protection technology of borehole is a recently developed method to maintain the drainage efficiency in deep mining level. However, the potential negative impact of screen pipes on CMM drainage efficiency has not been well studied. To investigate this impact, an innovative coal permeability model from elastic to post-failure state was deduced to develop our previous gas migration model. Then redistributed stress, coal permeability and gas pressure around a borehole were studied by implementing the mathematical model into Comsol Multiphysics. Numerical results indicate that the negative impact of screen pipes on drainage subpressure do not affect the drainage efficiency due to the stress redistribution. Engineering application shows that comparing to the traditional borehole protection technology, the gas concentration increases about 120% and the gas flux increases about 110% by using the fast and whole protection technology. The research will provide theoretical foundation of CMM capture and borehole protect technology and is of great significance for the CMM utilization and the global environment.

Fugitive Methane Emissions from Indian Coal Mining and Handling Activities: Estimates, Mitigation and Opportunities for its Utilization to Generate Clean Energy

Abstract Fugitive methane emissions from fossil fuel extraction account for significant contribution towards greenhouse gas (GHG) emissions in India. Out of total all-India GHG emissions of 1.88 million Gg-CO 2 equivalent in 2010 (with LULUCF), 48928.66 Gg-CO 2 equivalent belonged to fugitive emissions from fossil fuel extraction. Methane emission from coal mining and handling activities has increased from 0.555 Tg in 1991 to 0.765 Tg in 2012, as per national emission factors developed by CSIR-CIMFR. These estimates have been prepared as part of India's Second National Communication to the United Nations Framework Convention on Climate Change (UNFCCC) and the Biennial Update Report (BUR). With increasing demand of coal, current production is likely to touch around a billion tonnes by 2020. In this paper a time series data of coal production and associated fugitive methane emissions from coal mining and handling activities have been presented up to the year 2012. The methane released from coal mining and also coalbed methane can supplement India's scarce natural gas reserves and act as a GHG mitigation opportunity. There are several technologies to achieve this in India, which include: 1. Coalbed methane (CBM): There exists an estimated potential of 400 BCM of CBM in three provinces viz. Jharkhand, West Bengal and Chhatisgarh. Commercial scale exploitation of CBM has already begun in Raniganj Coalfield in India. 2. Coal Mine Methane (CMM): Three coalfields in the Damodar River Basin (Raniganj, Jharia and Bokaro) were studied for feasibility of recovery and utilization of CMM. Kalidaspur and Ghusick collieries in the Raniganj Coalfield, Murulidih, Amlabad, Sudamdih and Parbatpur mines in the Jharia Coalfield and Jarangdih and Sawang collieries in the East Bokaro Coalfield appear to be favourable sites for CMM recovery. 3. Ventilation Air Methane (VAM): Methane diluted by ventilating air in underground coal mines is vented to the atmosphere and may be captured for its gainful utilization. Our studies have revealed that utilization of VAM at Moonidih Mine of BCCL can lead to a net emission reduction of 0.62 million tonnes of CO 2 equivalent per year. 4. Abandoned Mine Methane (AMM): There has been no effort to quantify the potential of AMM resource in India so far. It is imperative, therefore to initiate a study for evaluation of AMM resource potential in India. Such mechanisms may serve as a valuable instrument to mitigate atmospheric methane emissions to the atmosphere and to find new pathways of clean energy deployment in India. This paper presents an analysis for policy-makers and the stake holders by providing a technological overview for augmenting clean energy resources in India.

Novel technology for coal mine methane utilization, process simulation and catalyst development

AbstractGlobal methane emission from coal mines were estimated to be approximately 584 MMTCO2 E in 2010, which is a huge waste of energy resources and is an important source of greenhouse gas (GHG) emission. Coal mine methane (CMM) whose methane content is 30∼60% with the rest of air is difficult to use directly. A novel process for CMM utilization is developed in this work. CMM is used as the feedstock for urea synthesis. This process does not require separation or further purification of CMM, but converts the methane into hydrogen through the oxygen in it and by adding steam. The reformate can be further processed into a mixture of hydrogen and nitrogen with a molar ratio of H2:N2 = 3:1, which can then be used for urea synthesis. This process has been analyzed by Aspen Plus. It is found that the optimal CMM composition for urea production is 42% of methane in the air system, with water added at an H2O/CH4 ratio of 3.26. Reforming catalyst has been developed and tested in a simulated industrial reactor, with CMM simulated by mixing civil use grade methane and air. The reformate composition was analyzed by gas chromatography (GC) and the results match the simulation very well. A 10‐day test showed high stability of the catalyst. In addition, the reforming catalyst after 10 days of operation was characterized using XRD and Laser Raman. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd.

Demonstration and its validation for ventilation air methane (VAM) thermal oxidation and energy recovery project

In the present work, a preliminary technical and demonstration running assessment had been conducted in the Dafosi coal mine, China. First commercially available technologies for both mitigation and utilization of coal mine methane (VAM) combined with drained low concentration methane by premixing and co-oxidation was briefly described. Based on the methane emission characteristics, the running properties of thermal flow reversal reactor (TFRR) and gas mixing unit have been analyzed systemically. Under the experimental condition, TFRR should be preheated for about 27 h until the central temperature of monolith bed reaching to about 1000 °C. Another 9 h are needed to make the temperature evolutes to the similar profiles under the stable operation conditions with the help of electric heater and fed methane gas oxidation. For the TFRR, about 31.61%–46.82% energy can be recovered and used for electricity generation at the stable running conditions. Methane concentration corresponding to TFRR stable and self-maintained running should not be less than 0.25%. However, the effective and economical operation with heat recovery for electricity generation is possible only for the methane concentrations higher than 0.6%, and recommended at 1.0 vol.% methane concentration.

Emission and commercial utilization of coal mine methane in the Upper Silesian Coal Basin illustrated by the example of Katowice Coal Holding Company

Abstract The article deals with the issue of the release of methane from coal seams and its emission to the atmosphere from the mines of Katowice Coal Holding Company in the years of 1997-2011. This period is characterized by organizational changes in Polish mining industry involving liquidation or a merger of mines, an increase in both the concentration of coal mining activity, and the depth of the exploitation at which the amount of methane in coal seams grows ever larger. The analysis of the variation in the methane emission from the coal mines in that period points out a decline in the intensity of the emission until 2005, probably owing to the liquidation of some mines, later, but in the years of 2006-2010 - a considerable increase in both the absolute methane emission of the mines and the methane emission to the atmosphere despite a dropping coal extraction. This signifies that mining activity takes place in increasingly difficult gas conditions prevailing at great depths. Despite a slight decrease in both the absolute methane emission and methane emission to the atmosphere in 2011, a continuously growing trend of this phenomenon should be expected in the future. A similar tendency is also visible in the whole Upper Silesian Coal Basin, however the methane emission peak falls in 2008. In order to curb the growth of the amount of the emitted methane, it should be commercially utilized. Particularly vital is considering methane as an unconventional resource, following the example of other countries.

Энергосберегающая технология утилизации шахтного метана

Энергосберегающая технология утилизации шахтного метана

Drainage and utilization of Chinese coal mine methane with a coal–methane co-exploitation model: Analysis and projections

Coal mine methane (CMM) released during coal mining attributes to unsafe working conditions and environmental impact. China, the largest coal producer in the world, is facing problems associated with CMM such as fatal gas accidents and intense greenhouse gas emission along the path to deep mining. Complicated geological conditions featured with low permeability, high gas pressure and gas content of Chinese coal seams have been hindering the coal extraction. To solve these problems, a model of coal–methane co-exploitation is proposed. This model realizes the extraction of two resources with safety ensured and has been successfully applied in Huainan coalfield, China. The current situation of drainage and utilization of CMM in China are diagnosed. Connections between the coal production, methane emissions, drainage and utilization are analyzed. Estimations of future coal production, methane emissions, drainage and utilization are made in a co-exploitation based scenario. The emitted, drained and utilized CMM are projected to reach 26.6, 13.3 and 9.3 billion m3, respectively by adapting the assumption of 3800 million metric tons of coal production by 2020.

Sponge Effect on Coal Mine Methane Separation Based on Clathrate Hydrate Method

The findings were presented from laboratory investigations on the hydrate formation and dissociation processes employed to recover methane from coal mine gas. The separation process of coal mine methane (CMM) was carried out at 273.15 K under 4.00 MPa. The key process variables of gas formation rate, gas volume stored in hydrate and separation concentration were closely investigated in twelve THF-SDS-sponge-gas systems to verify the sponge effect in these hydrate-based separation processes. The gas volume stored in hydrate is calculated based on the measured gas pressure. The CH 4 mole fraction in hydrate phase is measured by gas chromatography to confirm the separation efficiency. Through close examination of the overall results, it was clearly verified that sponges with volumes of 40, 60 and 80 cm 3 significantly increase gas hydrate formation rate and the gas volume stored in hydrate, and have little effect on the CH 4 mole fraction in hydrate phase. The present study provides references for the application of the kinetic effect of porous sponge media in hydrate-based technology. This will contribute to CMM utilization and to benefit for local and global environment.