Journal articles on the topic 'Bituminous rank coal beds'
To see the other types of publications on this topic, follow the link: Bituminous rank coal beds.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Bituminous rank coal beds.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Sherwani, Govand. "Preliminary Evaluation of Quality and Rank of Banik Coal, Zakho, Duhok Governorate, Kurdistan Region, Iraq." UKH Journal of Science and Engineering 5, no. 2 (December 28, 2021): 36–46. http://dx.doi.org/10.25079/ukhjse.v5n2y2021.pp36-46.
Full textAbstract:
This study aims to evaluate the rank (or grade) and economic value of so–called coal horizons outcropping in the vicinity of Banik and Shiranish-Islam villages of Zakho District, Duhok Governorate. These coal-like beds (locally known as Banik Coal) make up few meters within the upper part of the Jurassic Naokelekan Formation. The evaluation was mainly based on standard chemical tests of coal (proximate and ultimate analyses) achieved in foreign and local laboratories. The test results were assessed according to the standard coal tests introduced by the American Society for Testing and Materials (ASTM). The latest stratigraphic studies revealed that the presumable coal horizons were thin beds of limestone and dolomitic limestone alternated with frequent shales all impregnated with bituminous materials, mostly of hydrocarbon source. The bituminous beds were traced in both upper and lower parts of Naokelekan Formation. The standard proximate coal analysis has shown low percent of fixed carbon and high percent of volatiles and ash which support the hydrocarbon source of these bituminous beds. Consequently, it would be difficult to classify these bituminous beds similarly to the standard coal ranks of ASTM. The high values of mineral matter display the dominance of minerals rather than the carbon in the local samples. However, the Gross Calorific Value (heating value) of these beds would imply that they can be used as relatively poor quality source of fuel. Besides, the exploitation of Banik coals would be influenced by the cost of extraction (or mining), the expected prices of produced coal, and the prices of alternative sources of energy.
2
Adamczyk, Zdzisław, Joanna Komorek, and Małgorzata Lewandowska. "SPECIFIC TYPES OF COAL MACERALS FROM ORZESZE AND RUDA BEDS FROM ”PNIÓWEK” COAL MINE (UPPER SILESIAN COAL BASIN – POLAND) AS A MANIFESTATION OF THERMAL METAMORPHISM." Archives of Mining Sciences 59, no. 1 (March 1, 2014): 77–91. http://dx.doi.org/10.2478/amsc-2014-0006.
Full textAbstract:
Abstract Subject of the research were coal samples from the seams of Orzesze and Ruda beds from “Pniówek” coal mine. All samples represent methabituminous coal B, which present high vitrinite content (V mmf > 60%). Optical character of vitrinite from all analyzed coal samples is biaxial negative and it is characterized by low differentiation of bireflectance. The experiments have shown that the coal rank of investigated samples is generally decreasing with increasing both depth of coal seams and the distance between sampling point and the Carboniferous roof. It may suggests inversion of coalification. Specific types of macerals, typical for thermally metamorphosed coals have been found for all analysed coal samples. It was found, presence of such components like: fluorescing bituminous substance (FBS) filling of cellular spaces in semifusinite, fusinite, and funginite; pseudomorphs after megaspores exhibiting strong bireflectance, and anisotropic semifusinite. Petrographic components with a structure similar to structure of coke and pyrolytic carbon were observed rarely. Presence of colotelinite grains which are visible darker, impregnated with bituminous substance and exhibiting weak fluorescence may be related with influence of temperature on coal. Carbonates occur as filling of cellular spaces in semifusinite, in examined coal samples and there are the effect of thermal alteration of coal.
3
Morcote, Anyela, Gary Mavko, and Manika Prasad. "Dynamic elastic properties of coal." GEOPHYSICS 75, no. 6 (November 2010): E227—E234. http://dx.doi.org/10.1190/1.3508874.
Full textAbstract:
Laboratory ultrasonic velocity measurements of different types of coal demonstrate that their dynamic elastic properties depend on coal rank and applied effective pressure. In spite of the growing interest in coal beds as targets for methane production, the high abundance in sedimentary sequences and the strong influence that they have on seismic response, little data are available on the acoustic properties of coal. Velocities were measured in core plugs parallel and perpendicular to lamination surfaces as a function of confining pressure up to [Formula: see text] in loading and unloading cycles. P- and S-wave velocities and dry bulk and dry shear moduli increase as coal rank increases. Thus, bituminous coal and cannel show lower velocities and moduli than higher ranked coals such as semianthracite and anthracite. The [Formula: see text] relationship for dry samples is linear and covers a relatively wide range of effective pressures and coal ranks. However, there is a pressure dependence on the elastic properties of coal for confining pressures below [Formula: see text]. This pressure sensitivity is related to the presence of microcracks. Finally, the data show that coal has an intrinsic anisotropy at confining pressures above [Formula: see text], the closing pressure for most of the microcracks. This intrinsic anisotropy at high pressures might be due to fine lamination and preferred orientation of the macerals.
4
Anand-Prakash. "Himalayan coals: their nature, composition, formation and rank." Journal of Palaeosciences 40 (December 31, 1991): 477–89. http://dx.doi.org/10.54991/jop.1991.1795.
Full textAbstract:
The results of maceral, microlithotype and reflectance analyses, so far carried out on the Palaeozoic (Permian) and Tertiary coals of Himalaya, have been presented along with the details of geological and chemical (proximate) studies. The Permian coals, enclosed in the sediments dispersed as thrust slices in the eastern Himalaya, are characterized by their high rank and the dominance of the maceral vitrinite. In general, these coals are classified as semianthracite, except for the Bhutan coals which are of low rank and high volatile bituminous in nature. Almost all the macerals contain fairly high amount of mineral matter. Finely disseminated argillaceous matter is the most common mineral suite present in the coals followed by carbonates and iron sulphide (pyrite). In most of the cases, the mineral matter is present as infillings in numerous sets of fissures which traverses the coals. These infillings seem to have been developed during the tectonic activity and represent secondary minerals impregnated in various macerals. Often the presence of high amount of mineral matter has greatly reduced the quality of coal. Besides, the marine animal fossil-bearing mineral concretions (coal balls) have indicated that these coals were formed in a series of lagoons under the influence of marine conditions.
The Upper Tertiary coals, associated with the Tipam sediments in the eastern Himalaya, occur as small lenses, very thin impersistent seams and pockets which are characterized by the dominance of maceral vitrinite. It is generally represented by the structured variety (telinite). In general, the cellular structures indicate that these coals have been formed by the burial of wood logs in the fluvial sediments. An important feature of telinite is the presence of folded tissues which attain prominence in the coals occurring closer to the main boundary faults. The coals in this area exhibit lignite-bituminous stage in rank and are comparable to the Mesozoic coals in peninsular India. This stage in rank has been possible mainly due to the tectonic disturbances.
The Lower Tertiary coals of Jammu area are the only economically workable deposits in the Himalayas. These are associated with the beds containing marine animal remains. This indicates that coal formation took place under near-shore environment. These coals are comparable to the Permian coals of the eastern Himalayas. They are also rich in maceral vitrinite and semianthracitic in rank. Such a high rank of these Tertiary coals may be attributed to the effect of tectonic movements in the Himalayan areas.
5
Sarate, O. S. "Biopetrological study of Mulug coal belt, Godavari Basin, Andhra Pradesh, India." Journal of Palaeosciences 43, no. 1-3 (December 31, 1994): 51–66. http://dx.doi.org/10.54991/jop.1994.1187.
Full textAbstract:
Biopetrological investigation of 12 coal seams from Mulug coal belt of Godawari Basin has been carried OUID evaluate their economic potentials. The coal seams are associated with the Karharbari and Barakar of the Lower Gondwana sequence. The maceral study has revealed that seams IV A, IV , 111 B, II, I below index, I and IA contain vitric coal. However, IV below index, III and I B seams are characterized by a mixture of both vtric and fusic coals. Besides, III A and II below index seams contain fusic coal. The microlithotype analysis indicates that the vitric coal has the dominance of vitrite, clarite and duroclarite constituents. The mixed type of coal contains variable frequencies of vitrite and inertite with intimate association of clarite, durite, trimacerite and carbominerite microlithotypes. However, fusic coal has overall dominance of inertite with carbominerite. The reflectance study revealed that I B, I and I below index, IV below index and the lowermost IV A seams have attained high volatile bituminous C rank. Whereas coal of II below index seam is represented by transitional stage of rank between high volatile bituminous C and sub-bituminous A. the coal seams III B and III A contain coal of high volatile bituminous B rank. However, the seams III and II are characterized by coal having rank ranging between high volatile bituminous C to B. Seam I A contains coal of high volatile bituminous C to A rank. However, seam IV comprises coal having reached high volatile bituminous A stage.
6
Li, Mingxue, Yonghan Long, Lucheng Guo, Shipan Zeng, Jiacheng Li, and Lei Zhang. "An Experimental Study on CO2 Displacing CH4 Effects of Different Rank Coals." Geofluids 2022 (October 15, 2022): 1–13. http://dx.doi.org/10.1155/2022/6822908.
Full textAbstract:
In order to study the effect of different rank coals on the displacement of CH4 by CO2 and prevent the gas-related disasters, a series of experiments were carried out. For this purpose, we selected low-rank lignite raw from Datong coalfield of Shanxi Province, medium-rank bituminous coal raw from Xutuan coalfield of Anhui Province, and high-rank anthracite raw coal from Yangquan coalfield of Shanxi Province. The results showed that (1) the shape of the displacement adsorption curve of the mixed gas and the shape of the single-dimensional adsorption curve of the pure gas are both steep at the beginning, with the increase of the pressure, the curve becomes more and more gentle. The difference is that it is lower than the single-dimensional gas adsorption curve. (2) The separation factor in the coal samples used in the experiment shows a trend of first decreasing and then increasing with the decrease of coal rank. The displacement factor has the same trend as the separation factor of each coal rank, which is Z i j anthracite > Z i j lignite > Z i j bituminous coal . (3) The amount of displaced CH4 in the displacement/adsorption process has enhanced with the increase in pressure, and the trend for different coals is Q Z bituminous coal > Q Z anthracite > Q Z lignite . In addition, displacement showed the order ƞ lignite > ƞ anthracite > ƞ bituminous coal . The injection ratio of bituminous coal and anthracite decrease with the increase in pressure, while that of lignite increase first and later decreased. (4) In gas injection displacement, on the long time, the displacement effect of high coal rank is better than that of low coal rank.
7
Sarate, O. S. "Biopetrological study of coals from Ramagundam coalfield, Godavari basin, Andhra Pradesh, India." Journal of Palaeosciences 43, no. 1-3 (December 31, 1994): 122–38. http://dx.doi.org/10.54991/jop.1994.1195.
Full textAbstract:
A detailed petrographic study of eight coal seams from Ramagundam Coalfield, Andhra Pradesh is presented here. The top section of the coal seam I A, I, II, III A, III and IV contains workable thickness. Reflectance study has revealed that the seams IA (middle), III B, III A, III (top) and IV contain coal of high volatile bituminous C rank. Coal seams I A (top and bottom parts), I, II and III (middle) seams/part thereof are constituted by alternate coal bands of high volatile bituminous C and high volatile bituminous B rank. Besides, coal seam III and coal bands present below I seam have attained intermediate stage (high volatile bituminous C to sub-bituminous A) and high volatile bituminous C rank. Index seam is represented by coal of high volatile bituminous C and intermediate stage of the rank. The maceral study has revealed that the different seams are characterized mostly by the dominance of collinite maceral. Occasionally cracks in the vitrinite bands are filled either by clay or pyrite (grains/framboids) inerals. Exinite is represented by the microspore and megaspores of variable shape and size, sporangia, seeds, resin bodies, tenui and crassi-cutinites and algal elements. Inertinite Group is characterized by fusinite, semifusinite, inertodetrinite, sclerotinite and pyro-and degrade-fusinite macerals. Transition from vitrinite to semifusinite and semifusinite to fusinite is frequently observed. The microlithtype analysis has shown that the shaly coal, bright and dull coal have characteristic composition. These coals have been grouped under three categories as vitric, fusic and mixed (vitro-fusic and fuso-vitric) type. It is inferred that the sight of deposition has been a tectonically controlled slowly sinking basin.
8
Liu, Sheng Yu, and Hong Zhi Lu. "Research of Low Rank Bituminous Coal Heat Treating and Hydrogenation Upgrading." Advanced Materials Research 347-353 (October 2011): 3740–43. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.3740.
Full textAbstract:
This paper developments the research of improving the plasticity of low rank bituminous coal. The purpose is to improve the caking property of low rank bituminous coal and expand coking coal resources. The hydrothermal treatment, co-pyrolysis adding waste plastic and hydrogenation processing are chosen to process low rank bituminous coal. Several means including FTIR spectroscopy, thermogravimetric analysis, gas chromatographic(GC) and caking index are used to analyze the treated coal and generated gas products. The results show that the carboxyl groups of coal are removed after hydrothermal treatment, and the intensity of hydroxyl absorption increases. The oxygen-containing functional groups except hydroxyl groups of coal are removed after hydrogenation. The hydrogenation has obvious effects on the changes of coal structure. The reactivity and caking property of hydrotreated coal increases significantly, the indexes of coke quality of hydrotreated coal is measured to reach 16. The co-pyrolysis hydrogenation of plastic and coal results show that coal can prevent the thermal decomposition products of plastics from escaping. The caking index of hydrotreated coal with plastic is much same as that of hydrotreated coal. The addition of plastic in hydrogenation processing can not directly improve the coal plasticity.
9
Qin, Dingyi, Qianyun Chen, Jing Li, and Zhaohui Liu. "Effects of Pressure and Coal Rank on the Oxy-Fuel Combustion of Pulverized Coal." Energies 15, no. 1 (December 31, 2021): 265. http://dx.doi.org/10.3390/en15010265.
Full textAbstract:
Pressurized oxy-fuel combustion technology is the second generation of oxy-fuel combustion technology and has low energy consumption and low cost. In this research, a visual pressurized flat-flame reaction system was designed. A particle-tracking image pyrometer (PTIP) system based on a high-speed camera and an SLR camera was proposed. Combining the experimental system and data-processing method developed, the ignition and combustion characteristics of a single coal particle between 69 and 133 μm in size were investigated. The results indicated that at atmospheric pressure, the ignition delay time of ShanXi (SX) anthracite coal was longer than that of ShenHua (SH) bituminous coal, while that of PRB sub-bituminous coal was the shortest. As the pressure rose, the ignition delay time of the PRB sub-bituminous coal and SX anthracite coal showed a continuous increasing trend, while the ignition delay time of SH bituminous coal showed a trend of first increasing and then decreasing. Moreover, pressure also affects the pyrolysis process of coal. As the pressure increases, it became more difficult to release the volatiles produced by coal pyrolysis, which reduced the release rate of volatiles during the ignition stage, and prolonged the release time and burning duration time of volatiles.
10
Kopparthi, V., and S. R. Gollahalli. "Nitric Oxide Emission From Pulverized Coal Blend Flames." Journal of Energy Resources Technology 117, no. 3 (September 1, 1995): 228–33. http://dx.doi.org/10.1115/1.2835345.
Full textAbstract:
An experimental study of the nitric oxide emission from pulverized blended coal flames as a function of blending mass ratio is presented. Coals of three ranks (anthracite, bituminous, and lignite), and of the same rank (bituminous), but of different origin (Oklahoma and Wyoming mines), were used as fuels. Also, their blends (anthracite-bituminous, anthracite-lignite, lignite-bituminous, and Oklahoma-Wyoming coals) at mass ratios of 20:80, 40:60, 60:40, and 80:20 were studied. Correlations of nitric oxide emission index (mass/unit energy release) with blend mass ratio are presented.
11
Liu, Jian Zhong, Yu Jie Yu, Jun Hu Zhou, Chong Du, Lin Ye, Jun Cheng, and Ke Fa Cen. "Study on the Effects of Coal Blending on the Slurry Ability of Shenmu Coals." Advanced Materials Research 383-390 (November 2011): 3011–16. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.3011.
Full textAbstract:
Shenmu coals as low rank coal are difficult to prepare for Coal Water Slurry (CWS). The maximum slurry concentration of Shenmu CWS is lower than 60%, which is not available for practical application. Coal blending is a simple operation and low cost method to improve the slurry ability of low rank coal. Two different kinds of anthracite and bituminous coal samples were blended in Shenmu coal to study the effect on the preparation of CWS, respectively. The results showed that the maximum solid concentration of CWS increased as the proportion of high rank coal rise. And the viscosity of CWS is dropped at the same concentration. Different coals blending have different effects on the elevation of slurry ability for Shenmu coal. The raw coal with best slurry ability is not always the most suitable for blending in low rank coal. HuanNan bituminous coal is the best choice for blending in Shenmu coal. The maximum solid concentration of CWS can be increased by 6% when the proportion of HuanNan coal reached to 70%.
12
Fatima, Noureen, Asif Jamal, Zaixing Huang, Rabia Liaquat, Bashir Ahmad, Rizwan Haider, Muhammad Ishtiaq Ali, et al. "Extraction and Chemical Characterization of Humic Acid from Nitric Acid Treated Lignite and Bituminous Coal Samples." Sustainability 13, no. 16 (August 11, 2021): 8969. http://dx.doi.org/10.3390/su13168969.
Full textAbstract:
Currently, conversion of coal into alternative fuel and non-fuel valuable products is in demand and growing interest. In the present study, humic acid was extracted from two different ranks of coal, i.e., low rank and high rank (lignite and bituminous), through chemical pretreatment by nitric acid. Samples of lignite and bituminous coal were subjected to nitric acid oxidation followed by extraction using KOH and NaOH gravimetric techniques. The chemical pretreatment of both types of coal led to enhanced yields of humic acid from 21.15% to 57.8% for lignite low-rank coal and 11.6% to 49.6% bituminous high rank coal. The derived humic acid from native coal and nitric acid treated coal was analyzed using elemental analysis, E4/E6 ratio of absorbance at 465 nm and 665 nm using UV-Visible spectrophotometry and Fourier transformed infrared spectroscopy FTIR. The chemical characteristics of coal treated with nitric acid have shown increased molecular weight and improved aromaticity with more oxygen and nitrogen and lower C, H, and sulphur content. The E4/E6 ratio of nitric acid-treated low and high ranks of coal was high. The FTIR spectroscopic data of nitric acid-treated lignite coal indicates an intensive peak of carboxyl group at 2981.84 cm−1, while bituminous coal was shown in cooperation with the N-H group at 2923.04 cm−1. SEM was performed to detect the morphological changes that happen after producing humic acid from HNO3 treatment and native coal. The humic acid produced from HNO3 treated coal had shown clear morphological changes and some deformations on the surface. SEM-EDS detected the major elements, such as nitrogen, in treated humic acid that were absent in raw coal humic acid. Hence, the produced humic acid through HNO3 oxidation showed a more significant number of humic materials with improved efficiency as compared to native coal. This obtained humic acid can be made bioactive for agriculture purposes, i.e., for soil enrichment and improvement in growth conditions of plants and development of green energy solutions.
13
Pickles, C. A., F. Gao, and S. Kelebek. "Microwave drying of a low-rank sub-bituminous coal." Minerals Engineering 62 (July 2014): 31–42. http://dx.doi.org/10.1016/j.mineng.2013.10.011.
Full text
14
Gollahalli, S. R., A. Prasad, and S. Gundavelli. "Lift-Off Characteristics and Flame Base Structure of Coal Seeded Gas Jet Flames." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 210, no. 5 (October 1996): 373–82. http://dx.doi.org/10.1243/pime_proc_1996_210_061_02.
Full textAbstract:
An experimental study of the burner rim stability characteristics and the flame base structure of flames co-fired with pulverized coal and propane gas is presented. Lift-off and reattachment characteristics are examined as functions of propane concentration in the jet stream for lignite, bituminous and anthracite coals. The effects on flame base structure are studied in terms of temperature, product species concentration and radiation profiles. The addition of lignite and anthracite coals favours the lift-off transitions. Bituminous coal, on the other hand, makes the flame more stable. The peak values of temperature and concentrations of major combustion product species in the flame stabilization region strongly depend upon the rank of coal. Among the coals tested, bituminous coal produces the highest peak temperature and its flame emits maximum radiation from the stabilization region. Anthracite and lignite coals produce somewhat comparable stability characteristics and structure of the flame base. The effects of coal rank are explained by the differences in volatile matter, moisture and pyrolysis characteristics of coals.
15
Zhang, Yihuai, Maxim Lebedev, Gregory Smith, Yu Jing, Andreas Busch, and Stefan Iglauer. "Nano-mechanical Properties and Pore-Scale Characterization of Different Rank Coals." Natural Resources Research 29, no. 3 (October 18, 2019): 1787–800. http://dx.doi.org/10.1007/s11053-019-09572-8.
Full textAbstract:
ABSTRACT Characterization of coal micro-structure and the associated rock mechanical properties are of key importance for coal seam exploration, coal bed methane development, enhanced coal bed methane production and CO2 storage in deep coal seams. Considerable knowledge exists about coal chemical properties, but less is known about the nanoscale to the micro-scale structure of coals and how they change with coal strength across coal ranks. Thus, in this study, 3D X-ray micro-computed tomography (with a voxel size of 3.43 µm) and nano-indentation tests were conducted on coal samples of different ranks from peat to anthracite. The micro-structure of peats showed a well-developed pore system with meso- and micro-pores. The meso-pores essentially disappear with increasing rank, whereas the micro-pores persist and then increase past the bituminous rank. The micro-fracture system develops past the peat stage and by sub-bituminous ranks and changes into larger and mature fracture systems at higher ranks. The nano-indentation modulus showed the increasing trend from low- to high-rank coal with a perfect linear relationship with vitrinite reflectance and is highly correlated with carbon content as expected.
16
Sarate, Omprakash S. "Petrographic appraisal of coals of sub-surface seams from Belampalli Coalfield, Godavari Valley, Andhra Pradesh." Journal of Palaeosciences 63, no. (1-2) (December 31, 2014): 51–62. http://dx.doi.org/10.54991/jop.2014.291.
Full textAbstract:
The present paper incorporates a detailed information about the maceral composition and the rank (reflectance Ro mean %) assessment of eight sub–surface coal seams, viz. IB, IA, I, IIB, II, III, IV and V encountered in Bore–hole No. 561 from Belampalli Coalfield of the Godavari Valley. The mineral matter free (m.m.f.) maceral study has suggested that the seam IB contain vitrinite rich coal or vitric type of coal whereas, the seam IIB has inertinite affluent or fusic coal. However, the seams IV and V have shown almost similar proportion of vitrinite and inertinite maceral groups, thus their coal is of mixed type. The seams I and III are represented by vitric and mixed coal types, whereas, IA and II seams are marked by the presence of vitric, fusic and mixed coal types. Most of the coal seams in general have reached high volatile bituminous C rank, barring the basal portion of the seams IV and V which have reached high volatile bituminous B stage. Similarly, a wide range of variation in vitrinite reflectance (Ro mean%) 0.53–1.1% has been recorded in seam II and thus the coal is of heterogeneous nature, having reached high volatile bituminous C, B and A stage of rank. The facies model (based upon the maceral and mineral matter association) drawn for these coal seams has indicated that the depositional site has primarily experienced alternate oxic and anoxic moor conditions. Since the seams in Belampalli Coalfield have consistency in thickness, vitrinite and inertinite rich constitution, low mineral matter association and has shown wide range of rank (reflectance) variation, therefore, the study area has potential to emerge as a productive centre of economically viable and commercially exploitable Coalfield of the Godavari Valley in near future.
17
Manoj, B., Ashlin M. Raj, and George Thomas Chirayil. "Facile synthesis of preformed mixed nano-carbon structure from low rank coal." Materials Science-Poland 36, no. 1 (May 18, 2018): 14–20. http://dx.doi.org/10.1515/msp-2018-0026.
Full textAbstract:
Abstract Coal is a natural energy resource which is mainly used for energy production via combustion. Coal has nanocrystals embedded in it, formed during the coalification process, and is an ideal precursor for nano-carbon dots and diamonds. Herein, we report a facile top-down method to synthesise nanodots and diamonds of the size of 5 nm to 10 nm from three different types of coal by simple chemical leaching. TEM analysis revealed the formation of a mixture of carbon dots, graphene layers, and quantum dots in bituminous coal and sub-bituminous coal. Raman analysis confirmed the existence of synthesized nanodiamond and nano-carbon mixed phase with defects associated with it. It is concluded that graphene quantum dots, nanodiamonds, graphene sheets and carbon dots present in coal can be extracted by simple chemical treatment. These structures can be tuned to photoluminescent material for various optoelectronic applications or energy harvesting devices like super capacitors.
18
Tian, Hui Ying, Yang Li, Ying Dou Zhang, Quan Sheng Liu, Ke Duan Zhi, Run Xia He, and Xiao Rong Zhang. "Fundamental Study on Steam Gasification Reactivity of Typical Different Metamorphic Grade Coals." Advanced Materials Research 953-954 (June 2014): 1201–4. http://dx.doi.org/10.4028/www.scientific.net/amr.953-954.1201.
Full textAbstract:
The steam gasification experiment of FJC lignite, BL lignite, SH bituminous and TT anthracite were carried out by using an own design WFSM-3060TL Catalyst Evaluation Unit apparatus. The infulence of coal rank on the steam gasification activity was investigated. Experiment conditions: heating rate:15°C/min (25°C-500°C), 2°C/min (500°C-850°C). The resuts show that gasification of lignite is better. With the deepening of coal rank, the steam gasifiction reactivity of coal samples decreases obviously, the higher the coal rank is, the worse the gasification reactivity is.
19
Nyakuma, Bemgba Bevan, and Aliyu Jauro. "Chemical and Pyrolytic Thermogravimetric Characterization of Nigerian Bituminous Coals." GeoScience Engineering 62, no. 3 (December 1, 2016): 1–5. http://dx.doi.org/10.1515/gse-2016-0017.
Full textAbstract:
Abstract The discovery of new coal deposits in Nigeria presents solutions for nation’s energy crises and prospects for socioeconomic growth and sustainable development. Furthermore, the quest for sustainable energy to limit global warming, climate change, and environmental degradation has necessitated the exploration of alternatives using cleaner technologies such as coal pyrolysis. However, a lack of comprehensive data on physico-chemical and thermal properties of Nigerian coals has greatly limited their utilization. Therefore, the physico-chemical properties, rank (classification), and thermal decomposition profiles of two Nigerian bituminous coals – Afuze (AFZ) and Shankodi-Jangwa (SKJ) – were examined in this study. The results indicate that the coals contain high proportions of C, H, N, S, O and a sufficiently high heating value (HHV) for energy conversion. The coal classification revealed that the Afuze (AFZ) coal possesses a higher rank, maturity, and coal properties compared to the Shankodi-Jangwa (SKJ) coal. A thermal analysis demonstrated that coal pyrolysis in both cases occurred in three stages; drying (30-200 °C), devolatilization (200-600 °C), and char decomposition (600-1000 °C). The results also indicated that pyrolysis at 1000 °C is not sufficient for complete pyrolysis. In general, the thermochemical and pyrolytic fuel properties indicate that the coal from both places can potentially be utilized for future clean energy applications.
20
Su, Yinjiao, Xuan Liu, Yang Teng, and Kai Zhang. "A Preliminary Study on Dependence of Mercury Distribution on the Degree of Coalification in Ningwu Coalfield, Shanxi, China." Energies 14, no. 11 (May 27, 2021): 3119. http://dx.doi.org/10.3390/en14113119.
Full textAbstract:
Mercury (Hg) is a toxic trace element emitted from coal conversion and utilization. Samples with different coal ranks and gangue from Ningwu Coalfield are selected and investigated in this study. For understanding dependence of mercury distribution characteristics on coalification degree, Pearson regression analysis coupled with Spearman rank correlation is employed to explore the relationship between mercury and sulfur, mercury and ash in coal, and sequential chemical extraction method is adopted to recognize the Hg speciation in the samples of coal and gangue. The measured results show that Hg is positively related to total sulfur content in coal and the affinity of Hg to different sulfur forms varies with the coalification degree. Organic sulfur has the biggest impact on Hg in peat, which becomes weak with increasing the coalification degree from lignite to bituminous coal. Sulfate sulfur is only related to Hg in peat or lignite as little content in coal. However, the Pearson linear correlation coefficients of Hg and pyritic sulfur are relatively high with 0.479 for lignite, 0.709 for sub-bituminous coal and 0.887 for bituminous coal. Hg is also related to ash content in coal, whose Pearson linear correlation coefficients are 0.504, 0.774 and 0.827 respectively, in lignite, sub-bituminous coal and bituminous coal. Furthermore, Hg distribution is directly depended on own speciation in coal. The total proportion of F2 + F3 + F4 is increased from 41.5% in peat to 87.4% in bituminous coal, but the average proportion of F5 is decreased from 56.8% in peat to 12.4% in bituminous coal. The above findings imply that both Hg and sulfur enrich in coal largely due to the migration from organic state to inorganic state with the increase of coalification degree in Ningwu Coalfield.
21
Liu, Shiqi, Shuxun Sang, Tian Wang, Yi Du, Jinlong Jia, and Huihuang Fang. "The effects of CO2 on organic groups in bituminous coal and high-rank coal via Fourier transform infrared spectroscopy." Energy Exploration & Exploitation 36, no. 6 (March 19, 2018): 1566–92. http://dx.doi.org/10.1177/0144598718764752.
Full textAbstract:
The interactions between supercritical CO2 and coal and their effects on changes in the coal pore structure and organic groups play a critical role in the CO2 geological storage-enhanced coalbed methane recovery. To investigate the effects of supercritical CO2 on organic groups in coals of different ranks and its mechanisms under different temperature and pressure conditions, CO2 sequestration processes in bituminous coals and high-rank coals were replicated using a high-pressure reactor. Four coal samples of different ranks were exposed to supercritical CO2 and water under three temperatures and pressures for 240 h. Fourier transform infrared spectroscopy was used to provide semiquantitative ratios and Fourier transform infrared spectra of coal samples before and after the supercritical CO2–H2O treatment. The results show that interactions between supercritical CO2 and coal were controlled by the coal macromolecular structure, and semianthracite is the inflection point of interaction characteristics for coal samples of different ranks. Bituminous coal, including high- and low-volatility bituminous coal, has a low degree of condensation of its aromatic structure, and its aromatic nuclei can facilitate addition reactions. Swellings primarily break cross-links between aromatic nuclei in the same aromatic layer. These characteristics favor the polymerization addition of aliphatic side chains of aromatic nuclei, causing an increase in the degree of condensation of the aromatic structures in bituminous coal. High-rank coals including semianthracite and anthracite have a high degree of condensation of their aromatic structures, and the aromatic nuclei favor substitution reactions. Swellings primarily break cross-links connecting different aromatic layers, and bond dissociation reactions and sulfuration reactions are more significant for high-rank coal. These characteristics cause a decrease in the degree of condensation of the aromatic structure in high-rank coal. Temperature and pressure have a great impact on interactions between supercritical CO2 and coal and are controlled by the reaction types of the organic groups. With the increase in experimental temperature and pressure, the changes in the organic group content can be classified as the descending type, the rising type, the lower opening parabola type, and the upper opening parabola type. 45.0°C and 10 MPa is the inflection point of the changes in the organic group content. Descending- and rising-type changes favor addition, bond dissociation, and sulfuration reactions, which are endothermic. The reaction rate of supercritical CO2 and the organic groups increases, and the effects caused by temperature and pressure decrease as the temperature and pressure increase. Lower opening parabola- and upper opening parabola-type changes favor substitution, oxidation, and addition polymerization reactions, which are exothermic. These changes were significantly affected by a variety of reactions and were suppressed by high temperature and pressure. When the temperature is ≤45.0°C and the pressure is ≤10 MPa, supercritical CO2 has remarkable effects on alkyl and hydroxy groups and has a stronger effect on bituminous coal. When the temperature is >45.0°C and the pressure is >10 MPa, supercritical CO2 has remarkable effects on oxygen- and sulfur-containing groups and has a greater effect on high-rank coals.
22
Ni, X. M., Q. F. Jia, and Y. B. Wang. "Characterization of Permeability Changes in Coal of High Rank during the CH4-CO2 Replacement Process." Geofluids 2018 (November 12, 2018): 1–8. http://dx.doi.org/10.1155/2018/8321974.
Full textAbstract:
The influences of coal matrix expansion/contraction and effective stress on the permeability of coal with different thermal maturities are different during the CH4-CO2 replacement process due to different mechanical properties and gas adsorption capacities. To accurately predict the variation law of coal permeability during the CH4-CO2 replacement process, it is critical to understand how the matrix expansion/contraction and effective stress affect the permeability of coal at different thermal maturities during the CH4-CO2 replacement. In this study, the permeability of two coal specimens with anthracite and high-rank bituminous coal during the CH4-CO2 replacement process under different confining and injection pressures was tested using a CBM replacement testing machine. The results demonstrate that with decreasing gas injection pressure, the permeability of the two coal specimens exhibited a U-shaped correlation under different confining pressures. Under the same gas injection pressure, with increasing effective stress, the permeability presented a negative exponential decrease and the permeability of the anthracite decreased more significantly. Moreover, under the same confining pressure, with increasing gas injection pressure, the decreasing permeability agreed with Langmuir curve and the permeability of high-rank bituminous coal was more significantly reduced.
23
Djohor, Denny Suwanda, and Harry Pramudito. "KARAKTERISTIK BATUBARA FORMASI WARUKIN DALAM PEMBENTUKAN CBM DI WILAYAH KABUPATEN TANAH BUMBU, PROVINSI KALIMANTAN SELATAN." PENELITIAN DAN KARYA ILMIAH 2, no. 1 (January 1, 2018): 14. http://dx.doi.org/10.25105/pdk.v2i1.2455.
Full textAbstract:
Increasing world oil prices have a huge impact on national energy needs. Indonesia's economic growth requires the development of alternative energy sources based on 10 basin assessments in Indonesia, coal methane gas potential is estimated to reach 337 TCF of gas in place (Advanced Resources International, inc). The research location is located in the Basin of Asam-Asam,South Kalimantan. Targeted research on the Miocene Warukin Formation. The data used to evaluate Coal Methane Gas potential include surface geology data and coal sample analysis, as well as characteristics of regional anomaly bouger for South Kalimantan. The development of cleats and fractures in coal at the observation site can be classified into high-intensity vitamite-rich coal categories. Coal Warukin Formation has an average Rv value = 0.56% with standard deviation 0.02%. and is ranked in sub-bituminous coal rank. While for other Warukin Formation coal has an average Rv value = 0.58% and entered in rank (bit) bituminous coal with type of methane gas is the type of bio & thermogenic gas mixture. When viewed from the thick layer of coal and gas type, the Warukin Formation coal in the location of research is quite interesting when included in the coal resources of economical coal methane gas.
24
Li, Gui Zhong, Hong Yan Xu, Bo Wang, Ze Deng, and Meng Geng. "Research on Main Control Factors of Coalbed Methane Reservoir Formation in Turpan-Hami Basin." Advanced Materials Research 233-235 (May 2011): 2201–4. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.2201.
Full textAbstract:
Turpan-Hami Basin is a typical low coal rank coal bearing basin in China, with coal resources accounting for 50% of the total low coal rank resources. Structural evolution of the basin plays important controlling roles to generation；Fan delta and braided delta deposit systems are thick and stable sedimentary systems which are favorable for coal beds development；Hydrogeological condition is a major force for the adjustment and construction of coal-bed gas reservoirs.
25
Mustoe, George E. "Cyclic sedimentation in the Eocene Allenby Formation of south-central British Columbia and the origin of the Princeton Chert fossil beds." Canadian Journal of Earth Sciences 48, no. 1 (January 2011): 25–43. http://dx.doi.org/10.1139/e10-085.
Full textAbstract:
Extensive deposits of Eocene conglomerate, sandstone, shale, and sub-bituminous coal occur within a half-graben at Princeton, British Columbia. These strata comprise ∼2000 m of fluvial sediment interbedded with tephra and volcanic flows. Near the southeast margin of the basin, ∼200 m of rhythmically bedded strata are exposed along the Similkameen River. Cyclic deposition resulted from repeated episodes of hydrologic and topographic change related to seismic activity along the Boundary Fault on the east flank of the Princeton Basin, where Allenby Formation sediments are juxtaposed against metamorphic and metavolcanic rocks of the Upper Triassic Nicola Group. Interbedded carbonaceous shale and tuffaceous sandstone record influxes of distal lahar deposits into a lowland swamp. Coal–breccia transitions originated when debris flows along the scarp carried volcanic debris into adjacent wetlands. Coal–chert rhythmites are inferred to be evidence of hydrologic changes associated with floodplain tilt events that caused lowland to repeatedly alternate between a stagnant pond (“fen”) and a stream-fed lake. During fen stages, peat was silicified in situ from percolation of groundwater carrying silica dissolved from underlying tuffaceous beds. Episodic influxes of stream flow reduced dissolved silica concentrations and caused increases in dissolved oxygen levels. These geochemical changes caused organic matter that accumulated during these conditions of open water circulation to remain unsilicified and susceptible to partial maceration. Diagenesis eventually converted these deposits to alternating beds of sub-bituminous coal intercalated with chert horizons.
26
O. Odeh, Andrew, Samuel E Ogbeide, and Charity O Okieimen. "Elucidation of the Degradation of Poly Aromatic Hydrocarbon (PAH) in Coals During Pyrolysis." Energy and Environment Research 6, no. 2 (December 2, 2016): 27. http://dx.doi.org/10.5539/eer.v6n2p27.
Full textAbstract:
In this paper, we explore the use of high resolution transmission electron microscopy (HRTEM) in the degradation of the poly aromatic hydrocarbon (PAH) in coals of different ranks subjected to chemical plus heat treatment. The crystallite diameter on peak (10) approximations, La (10), of 37.6 Å for the high rank coal char at 700 oC fell within the HRTEM’s range of minimum-maximum length boundary of 11 x 11 aromatic aromatic fringes (28 – 44 Å). The La (10), 30.5 Å for the low rank lignite chars fell nearly on the minimum-maximum length range of 7 x 7 aromatic fringes (17 – 28 Å).The HRTEM results showed that the high rank anthracite chars at 700 oC comprised a higher distribution of larger distribution of larger aromatic fringes (11 x 11 parallelogram catenations). The mechanism for the similarity between coal chars of different ranks was the greater transition occurring in the low rank coals (lignite and sub-bituminous) to match the more resistant medium and high rank coals (bituminous – anthracite). This emphasized that the transitions in the properties of the low rank coals were more thermally accelerated than those of the high rank coals. The total PAHs detected in the coals of different ranks during pyrolysis are dominated by two- and three- ring PAHs. The amount of PAHs increase and then decrease with increase in pyrolysis temperature.
27
Ariunaa, A., D. Bernhardt, M. Beckmann, K. Gebauer, N. Hack, A. Seifert, R. Fischer, S. Unz, J. Narangerel, and B. Purevsuren. "Research on the thermal decomposition of Mongolian Baganuur lignite and Naryn sukhait bituminous coal." Mongolian Journal of Chemistry 16 (March 22, 2016): 22–29. http://dx.doi.org/10.5564/mjc.v16i0.665.
Full textAbstract:
The technical characteristics, elemental composition of the organic and mineral matters, ash melting behaviors and carbonization and gasification reactivities of coals from Baganuur and Naryn sukhait deposits were investigated. The results of proximate and ultimate analysis confirmed that the coal from Baganuur deposit can be graded as a low rank lignite B2 mark coal and Naryn sukhait coal is a bituminous G mark one. The carbonization and gasification experiments were performed using TGA apparatus and fixed bed quartz reactor. The data obtained with two experimental reactors showed that Baganuur lignite had lower thermal stability and much higher CO2 gasification reactivity at 950°C as compared to those for Naryn sukhait bituminous coal.Mongolian Journal of Chemistry 16 (42), 2015, 22-29
28
Julismi, Rusdianasari, and Abu Hasan. "Syngas Underground Coal Gasification (UCG) Testing of In-Situ Type Lignite Coal and Fracture Type Coal." International Journal of Research in Vocational Studies (IJRVOCAS) 1, no. 2 (September 22, 2021): 67–78. http://dx.doi.org/10.53893/ijrvocas.v1i2.42.
Full textAbstract:
The advancement and utilization of technology require energy, namely electricity and fuel energy. The increasing cost of fossil energy, the scarcity of non-renewable energy sources and the increasing energy demand requires diversification of energy resources. One of the new renewable energy sources currently being developed in Indonesia is Underground Coal Gasification (UCG). UCG is a new technology that utilizes unmined coal. In the UCG process, coal is burned underground and the syngas produced is collected through bore wells for processing or direct use. The resulting syngas is analyzed to see the effect of in-situ type of lignite coal and fractured type of coal on syngas production using the UCG method. Tests carried out on fracture-type lignite coal for 120 minutes with a sample weight of 1.3 kg obtained a CH4 gas concentration of 0.24%, which is relatively low compared to the in-situ type lignite coal sample CH4 gas concentration of 1.13%. The CO2 concentration was 54.46% in the fracture sample, and the In-Situ type sample was 52.19%. The O2 content with a value of 19.43% for the Fracture Type sample and 4.94% for the In-Situ type sample. Fracture Type and In-situ Lignite Coal produced fewer syngas products due to UCG testing than high-rank coals such as sub-bituminous and bituminous coal.
29
Lee, Byung Hwa, Jin Ho Kim, Gyu Bo Kim, Seng Mo Kim, and Chung Hwan Jeon. "Investigation of Tar/soot Yield of Bituminous and Low Rank Coal Blends." Journal of Energy Engineering 23, no. 2 (June 30, 2014): 42–48. http://dx.doi.org/10.5855/energy.2014.23.2.042.
Full text
30
Qian, Wei, Qiang Xie, Yuyi Huang, Jiatao Dang, Kaidi Sun, Qian Yang, and Jincao Wang. "Combustion characteristics of semicokes derived from pyrolysis of low rank bituminous coal." International Journal of Mining Science and Technology 22, no. 5 (September 2012): 645–50. http://dx.doi.org/10.1016/j.ijmst.2012.08.009.
Full text
31
Bonnett, Raymond, Franciszek Czechowski, and Paul S. Hughes. "Porphyrin analysis and coal rank—Porphyrin index of Coalification for bituminous coals." Chemical Geology 91, no. 2 (August 1991): 193–206. http://dx.doi.org/10.1016/0009-2541(91)90091-5.
Full text
32
Zhang, He, Wenli Liu, Hongxiang Xu, Qiming Zhuo, and Xiaopeng Sun. "Adsorption Behavior of Methyl Laurate and Dodecane on the Sub-Bituminous Coal Surface: Molecular Dynamics Simulation and Experimental Study." Minerals 9, no. 1 (January 9, 2019): 30. http://dx.doi.org/10.3390/min9010030.
Full textAbstract:
Biodiesel was found to be a more effective collector on low-rank coal flotation than the common oily collectors (diesel and kerosene) in previous research. However, the micro-adsorption behavior of these collectors on the coal surface remains to be further explored. In the present work, the adsorption behavior of methyl laurate and dodecane, representing biodiesel and common oily collectors, was investigated using experimental and molecular dynamics (MD) simulation methods. The results of MD simulations showed that dodecane was difficult to diffuse on the surface of sub-bituminous coal and formed a spherical structure on the surface of sub-bituminous coal. Methyl laurate was adsorbed on the surface of coal via the head group (ester group), while the tail group (alkyl chain) was exposed to a liquid environment, forming a wider network structure on the coal surface. The above results, mainly attributed to methyl laurate, had a higher interaction with the sub-bituminous surface compared to dodecane. The self-diffusion coefficient results showed that the aggregate configurations of methyl laurate cause higher water mobility, which was more conducive to enhancing the hydrophobicity of the coal surface. The adhesion efficiency measurement and X-ray photoelectron spectrometer (XPS) analysis confirmed that methyl laurate could cover more oxygen-containing functional groups on the coal surface than dodecane, thus enhancing the hydrophobicity of coal. The results of simulations conformed to the experimental results.
33
Umar, Datin, Suganal Suganal, Ika Monika, Gandhi Hudaya, and Dahlia Diniyati. "The influence of steam drying process on combustion behavior of Indonesian low-rank coals." Indonesian Mining Journal 23, no. 2 (November 2020): 105–15. http://dx.doi.org/10.30556/imj.vol23.no2.2020.1105.
Full textAbstract:
Steam drying process of the Low Rank Coals (LRCs) has been conducted to produce coal which is comparable with the High Rank Coal (HRC). Characterization of the raw and dried coals was carried out through proximate, ultimate, calorific value, Fourier Transform Infrared (FTIR) spectroscopy and Thermo Gravimetry-Differential Thermal Analysis (TG-DTA) to study the combustion behavior of the coals. This study used Indonesian low rank coals coming from Tabang (TKK coal) and Samurangau (SP coal), East Kalimantan. The results indicate that the calorific value of the dried coals increases significantly due to the decrease in moisture content of the coal. The FTIR spectrums show that the methylene-ethylene (RCH3/CH2) and aromaticity-aliphaticity ratios (Rar/al) of the dried coals increased while the ratio of RCO/ar decreased which reflect that the rank of the coals increased equivalent to the high rank coal (bituminous). Meanwhile, the TG-DTA indicates that the ignition temperature (Tig) and combustion rate (Rmax) of the dried coals increased. This analysis expresses that the dried coals produced by steam drying process have better combustion behavior due to the higher calorific value than those of the raw coals.
34
Kuznetsov, P. N., O. Y. Fetisova, L. I. Kuznetsova, X. Fan, B. Avid, and B. Purevsuren. "Key Peculiarities of the Pyrolysis Behavior of Different Rank Coals, and Characterization of the Pyrolysis Products." Eurasian Chemico-Technological Journal 24, no. 2 (July 25, 2022): 137. http://dx.doi.org/10.18321/ectj1326.
Full textAbstract:
The chemical composition, structural and plastometric properties of typical different-ranked coals from Mongolia deposits were studied. The non-isothermal iso-conversion Ozawa-Flynn-Wall method was used to assess kinetic parameters and to differentiate decomposition steps. Key peculiarities of the pyrolysis kinetics of brown and bituminous coals were revealed and discussed in terms of the composition and plastometric properties of coals. Brown coal was shown to undergo three decomposition steps with ever increasing activation energy as temperature increased because of the decomposition of thermally more and more stable molecular fragments. The pyrolysis of bituminous coals occurred in four steps, the activation energy having an extreme mode of temperature dependence. An important new finding was that the temperature range of the second, major pyrolysis step well corresponded to that between the softening and resolidification temperatures according to Gieseler plastometry, so that the decomposition of bituminous coals at the second step proceeded in a fluid-like medium, moreover, with constant activation energy. The yield and composition of the pyrolysis products obtained under isothermal conditions were also characterized depending on coal rank and temperature, and the ways for qualified utiliza tions were offered.
35
Parzentny, Henryk, and Leokadia Róg. "Evaluation the Value of Some Petrographic, Physico-Chemical and Geochemical Indicators of Quality of Coal in Paralic Series of the Upper Silesian Coal Basin and Attempt to Find a Correlation Between Them." Gospodarka Surowcami Mineralnymi 33, no. 1 (March 1, 2017): 51–76. http://dx.doi.org/10.1515/gospo-2017-0004.
Full textAbstract:
Abstract A total of 56 coal seam samples (from active and closed coal mines) representing USCB Paralic Series, were tested. It was determined that the tested coal has low content of mineral matter (especially in Hruśov Beds) as well as of Ag, As, Ba, Cd, Co, Cr, Cu, Mo, Ni, Rb, Sb, Sn, Sr, V and Zn. Only Mn and Pb content in coal is higher than in coal from other deposits around the world. There are differences in the values of physical and chemical, petrographic and geochemical indices of coal quality, between the northern and the south-western part of the USCB and in the profile of the Paralic Series. Thanks to the revealed correlations between the indices of coal quality, significant differences in the role mineral and organic substance play in concentrating some of the trace elements in the tested coal, were determined. Moreover, it was observed that an increase in the rank of coal (expressed with an increase in the value of R0 or/and Qsdaf or/and Cdaf), accompanies a decrease in the content of oxides of main elements in coal ash as well as sulfur and other trace elements in coal. The dependence was observed both in lateral and stratigraphic differences in the rank of coal. Mutual dependences between the indices of the rank of coal (R0, Cdaf, Qsdaf, Vdaf) in the northern and south-western area of the research and in Poruba Beds and Jaklovec Beds, were confirmed. It was determined that an increase in the value of Roga Index (RI) is accompanied by an increase in P2O5 content in ash of coal from the south-western part of the research area. It is probably a result of concurrence of a regional positive anomaly in the rank of coal and high P2O5 content in coal seams in the south-western part of the USCB. The observed increase in the value of RI, accompanying a decrease in the content of sulfate minerals, Cr and Ni in coal and Na2O in coal ash; results from the role the carbonisation process plays in distributing main and trace elements in the mineral matter of coal.
36
Beamish, B. B., J. D. St George, and M. A. Barakat. "Kinetic parameters associated with self-heating of New Zealand coals under adiabatic conditions." Mineralogical Magazine 67, no. 4 (August 2003): 665–70. http://dx.doi.org/10.1180/0026461036740125.
Full textAbstract:
AbstractAdiabatic self-heating tests were carried out on five New Zealand coal samples ranging in rank from lignite to high-volatile bituminous. Kinetic parameters of oxidation were obtained from the self-heating curves assuming Arrhenius behaviour. The activation energy E (kJ mol–1) and the pre-exponential factor A (s–1) were determined in the temperature range of 70–140°C. The activation energy exhibited a definite rank relationship with a minimum E of 55 kJ mol–1 occurring at a Suggate rank of ∼6.2 corresponding to subbituminous C. Either side of this rank there was a noticeable increase in the activation energy indicating lower reactivity of the coal. A similar rank trend was also observed in the R70 self-heating rate index values that were taken from the initial portion of the self-heating curve from 40 to 70°C. From these results it is clear that the adiabatic method is capable of providing reliable kinetic parameters of coal oxidation.
37
Haryono, Didied, Desiani, Mahfudz Al Huda, Warsito P. Taruno, Marlin R. Baidillah, and Irwin Maulana. "Characterization of Various Types Coal Using Capacitance Measurement Technique." Advanced Materials Research 1112 (July 2015): 506–9. http://dx.doi.org/10.4028/www.scientific.net/amr.1112.506.
Full textAbstract:
Each type of coal has different composition and properties, which determine the coal rank. One of the new methods for determining the quality of coal is by measuring its capacitance. It is formerly known that the difference in the moisture content of coal can be determined from the difference in its dielectric properties. The purpose of this paper is to characterize the various types of coal based on capacitance measurement. The samples used are Lignite, Sub-bituminous, Bituminous, and Anthracite. The proximate analysis testing was done to determine the content of moisture, volatile matter, ash, and fixed carbon. Capacitance value is measured using 2-channel data acquisition system (DAS) and parallel plate capacitive sensor at frequency 2.5 MHz. The results shows that the capacitance values of each type of coal are different. The capacitance value is affected by moisture content of coal since the moisture content and capacitance value have a linear correlation. And also, the signal characterization using frequency from 1 kHz to 5 MHz was performed to verify whether the frequency used in the DAS is able to characterize coal types.
38
Sarate, Omprakash S. "Petrographic analysis and depositional environment of subsurface coal seams of Koyagudem area, Godavari Valley Coalfield, Telangana, India." Journal of Palaeosciences 64, no. (1-2) (December 31, 2015): 151–61. http://dx.doi.org/10.54991/jop.2015.110.
Full textAbstract:
The study area marks the south-eastern extremity of the Mulug Coal Belt of Godavari Valley Coalfield, Telangana. The Bore-hole No. KYG-353, containing Index above Queen and Queen seams, is located in north-western direction from Kothagudem Town of Khammam District. The petrographic analysis has been done to ascertain their rank by random vitrinite reflectance (Ro mean %) measurements and quality estimation through maceral analysis, in order to interpret the environment of deposition as well as economic significance. The Index above Queen Seam has vitrinite group of maceral in dominance therefore, contains vitric type of coal whereas; the top and a band in the middle part of the Queen Seam contain coal which is fusic (inertinite rich) in nature. The bottom part of this seam has shown vitrinite in abundance indicating its vitric nature. The random vitrinite reflectance (Ro mean %) study has revealed that the coals of Index above Queen and the Queen seams have attained high volatile bituminous C stage of rank, except for a coal band located between 161.44 m and 162.44 m depth range, which has reached high volatile bituminous B rank. It is also inferred that the vegetal resource of Index above Queen Seam has been deposited during oxic and anoxic moor conditions; however, a distinct change in the climatic conditions to oxic moor with intermittent moderate to high flood situation occurred in the depositional phase of the Queen Seam. The study also suggests that coal deposits in this region have significantly high economic potentials.
39
Antoshchenko, Mykola, Vadym Tarasov, Oleksandr Nedbailo, Olha Zakharova, and Rudniev Yevhen. "On the possibilities to apply indices of industrial coal-rank classification to determine hazardous characteristics of workable beds." Mining of Mineral Deposits 15, no. 2 (2021): 1–8. http://dx.doi.org/10.33271/mining15.02.001.
Full textAbstract:
Purpose is to identify behaviour of the graded indices as well as their correspondence to grades, groups, and subgroups of similar coal metamorphic degrees to determine hazardous characteristics of workable beds while mining. Methods. Rank scale and changes in the graded index values help define the coal grades, groups, and subgroups having comparable characteristics as well as ultimate composition of organic mass. Coal ranking involves the intensified metamorphism manifestation in the process of transition from lignite to black coal, and then to anthracite. Findings. Analysis of the total of the fusainized components has shown that coal grading is within less than 10 and more than 69% range. However, in the majority of cases its values are recommended as those being less than 39 or more than 40% which prevents from determination of reliable correlation relationships. Free heaving ratio is considered together with the plastic layer thickness making it possible to determine quantitively only LF, LS, LC, and L grades. In terms of vitrinite response index, being 0.8-1.4%, LS, LC, and L grades may be considered as coal in the central ranking series. The fact supports available changes in the internal structure. Originality. Behaviour of the graded indices of industrial coal-rank classification has been determined to identify hazardous characteristics of workable beds while mining. Practical implications are the possibilities to improve the regulatory system for safe mining of workable beds while determining differences in characteristics of vitrinite coal and fusainized coal.
40
Rajagukguk, Yonathan Mangatur, and Stevanus Nalendra Jati. "Macerals Analysis Seam M2 Muaraenim Formation, : Implication Toward Coal Facies and Coal Rank in Kendi Hill, South Sumatra." Journal of Geoscience, Engineering, Environment, and Technology 3, no. 2 (June 1, 2018): 94. http://dx.doi.org/10.24273/jgeet.2018.3.2.670.
Full textAbstract:
The Muaraenim Formation is a coal bearing formation in South Sumatra Basin of the Late Miocene – Pliocene. Shell (1978) divides this formation based on coal seam content are: M1, M2, M3, and M4. Coal seam in this area include in seam M2 member, with the general characteristics of the presence of silicified coal on the roof and floor of coal seams as a marker. The administration of the research area is located in east Kendi Hill, South Sumatra. The Kendi Hill is composed of adesite igneous rocks that intruded Muaraenim Formation in unconformity at the time of Pleistocene. This study aims to determine the environment of coal depositional based on maceral analysis and determine the factors influence the physical characteristics of coal seams in Kendi Hill. Data that has been obtained from the field, then conducted a selection process. The number of samples analyzed were nine sample based on near and far to the Kendi Hill spread from the southern, central, and northern of the location. The result of the analysis will display the maceral diagram. Megascopically, coal seam in the Kendi Hill are black, dull with bright, uneven – subchoncoidal, blackish brown in streak, have a pyrite and resin. The thickness of the coal seams ranges from 0,45 to 14 meters. Based on the maceral analysis, the coal seam in the Muaraenim Formation is composed dominated by vitrinite, then liptinite, inertinite and mineral matter pyrite (1,6-6,6%). Vitrinite reflectance of coal in the research area ranges from (0,37-0,48%) that included to the Sub bituminous – High Volatile Bituminous C. From the results of Tissue Preservation Index and Gelification Index value indicated that the environment of coal depositional in the research area was a limnic to wet forest swamp. Whereas the deposition of the Muaraenim Formation in deltaic environment (Transitional lower delta plain).
41
Jiang, Jingyu, Qiang Zhang, Yuanping Cheng, Kan Jin, Wei Zhao, and Haijun Guo. "Influence of thermal metamorphism on CBM reservoir characteristics of low-rank bituminous coal." Journal of Natural Gas Science and Engineering 36 (November 2016): 916–30. http://dx.doi.org/10.1016/j.jngse.2016.11.030.
Full text
42
Matjie, R. H., J. R. Bunt, and J. H. P. van Heerden. "Extraction of alumina from coal fly ash generated from a selected low rank bituminous South African coal." Minerals Engineering 18, no. 3 (March 2005): 299–310. http://dx.doi.org/10.1016/j.mineng.2004.06.013.
Full text
43
Navale, G. K. B. "Temporal and spatial variations of the type and rank of Gondwana coals of India." Journal of Palaeosciences 40 (December 31, 1991): 468–76. http://dx.doi.org/10.54991/jop.1991.1794.
Full textAbstract:
Gondwana coals associated with Permian sediments in peninsular India vary widely but there is a distinct tendency of variation to be diagnostic both in time and space. The three maceral groups (Vitrinite, Liptinite and Inertinite) which are derived from diversified plant material exist in the Gondwana coals. However, maceral composition is controlled by the type of plant material available for accumulation as peat and by Eh and pH of the ancient swamp. These may all be in part controlled by the period when the peat was formed, climate and sedimentary environment. These variables seem to be inter-related rather than independent. The coals that occur in Karharbari, Barakar and Raniganj formations differ significantly in their nature and relative distribution of coal constituents.
The coals, deposited under wide range of tectonosedimentary settings of Permian Gondwana sequence, reveal fusic, trimaceric and vitric coal types and by and large associated with different lithologic sequences in ascending order. Provincialism can be discerned both in relation to lateral variation of individual seams and in differences between the modal composition found in different coal measures. Significant variation occurs within the individual seams, however, they retain some degree of characteristic petrological identity. Different seams in a given stratigraphic unit may differ widely in their petrographic composition but are characterized by their diagnostic modal composition. The coals of Damodar, Son-Mahanadi, Pench-Kanhan and Wardha-Godavari basins provide good examples for the temporal and spatial variation of the coal seams.
Coal rank assessed has shown significant variation in rank both in space and time ranging from high volatile sub-bituminous to low volatile bituminous stages including coking coal types. The wide range of coal rank recognized in the Gondwana of India is controlled by geothermal gradients and tectonic features. These have affected the extent of coalification by controlling the heat flow to which coals have been exposed. Tectonism may also have exercised some control over coal types (rank types) but only as a part of a complex mechanism which also involved sedimentary environment, the climate and the flora at any given time.
44
Oskay, R. G., H. Inaner, A. I. Karayigit, and K. Christanis. "Coal deposits of Turkey: properties and importance on energy demand." Bulletin of the Geological Society of Greece 47, no. 4 (September 5, 2013): 2111. http://dx.doi.org/10.12681/bgsg.11106.
Full textAbstract:
In the last two decades electricity generation and consumption in Turkey was increasing steadily. Around 80% of the electricity generated is derived from fossil fuels such as imported natural gas and oil, and domestic coal. As the energy policy now is focusing on reducing the dependency on imported fuels, coal, particularly this of low-rank, is becoming important for the country. Latest explorations showed that total coal reserves of Turkey reach to 13 Gt with low-rank coals (i.e. lignite and sub-bituminous) being dominant. Coal deposits, formed under various conditions and in various geological times, are widely spread over the territory. The most significant deposits are of Tertiary, especially Neogene age. Neogene coals are most appropriate for combustion in the thermal power plants due to the high total reserves despite the high ash yields and the low calorific values. We imply that applying reasonable exploitation planning and appropriate washing techniques, coal will play a key role in future energy supply of the country.
45
Susilawati, Rita. "NON-MINERAL INORGANIC CONSTITUENTS OF BUKIT ASAM COAL NATURE AND MODE OF OCCURRENCE." Buletin Sumber Daya Geologi 10, no. 2 (August 8, 2015): 14–30. http://dx.doi.org/10.47599/bsdg.v10i2.139.
Full textAbstract:
The nature and mode of occurrence of the non-mineral inorganic fractions in coal from the Bukit Asam coalfield South Sumatra Basin Indonesia were analysed using a combination of selective leaching, low temperature ashing, XRD, XRF and electron micropobe techniques. Geologically the rank of coal at Bukit Asam was influenced by igneous intrusion. Fourteen coal samples were used in this study. Samples are chosen to represent different rank levels as well as seam horizons. The inorganic elements, in the form of dissolved salts, exchangeable ions and organometallic complexes, although present in small proportions, contribute significantly to the mineral matter components of Bukit Asam low rank coal. Electron microprobe analysis showed small but significant concentrations of inorganic elements (Al, Ca and Fe) occurring in the individual macerals in two sub bituminous and twosemi anthracite samples. There is a tendency for some of the elements, particularly Ca and Al to be lost from the organic matter with rank advance. The concentrations of elements indicated by the microprobe are relatively in good agreement with the levels of element mobility indicated by selective leaching of the same whole-coal samples. The results of this study also suggest that non-mineral inorganic was likely act as a precursor for the reactions resulting in the formation of new minerals in the high rank coals at Bukit Asam.
46
Marwanza, Irfan, Chairul Nas, Masagus Ahmad Azizi, Riskaviana Kurniawati, and Ardiansyah. "THE ZONATION OF COAL RANK IN MUARA ENIM FORMATION BASED ON THE REFLECTION STUDY." Journal of Southwest Jiaotong University 56, no. 4 (August 30, 2021): 484–90. http://dx.doi.org/10.35741/issn.0258-2724.56.4.43.
Full textAbstract:
Coal is a sedimentary rock containing approximately 50% to 70% carbon derived from the accumulation of plant residue that had undergone chemical and physical changes. In this research, the petrographic analysis method of coal was conducted based on the following parameters, measuring vitrinite reflectance (Ro%), estimation of moisture, volatile matter, and carbon-hydrogen content. This study aims to determine the zonation of coal rank through the vitrinite reflectance analysis in Maura Enim Formation. The samples observed were obtained from the Muara Enim Formation, which had undergone certain geological events to form lignite and anthracite coal ranks, then analyzed using the descriptive method. The results showed that the reflectance value of vitrinite was between 0.20% - 0.44%, which was utilized in the sorting of coal from lignite - sub-bituminous, according to ASTM D2798-06 (2006). Furthermore, in the Southwest region, coal is formed through greater pressure than those in the Northeast. Generally, the level of difference is caused by pressure, temperature, and time factor. Therefore, this study is recommended as a guideline in determining coal rank through vitrinite reflectance analysis in different formations.
47
Xu, Guo Zhong, Xiang Yun Zhong, and Zhen Ning Zhao. "Effects of Foaming Condition on the Performance of Bituminous Coal-Derived Carbon Foams." Advanced Materials Research 557-559 (July 2012): 1186–91. http://dx.doi.org/10.4028/www.scientific.net/amr.557-559.1186.
Full textAbstract:
carbon foams were prepared using a medium rank bituminous coal in this paper. The influence of foaming temperature, foaming pressure and time of releasing pressure on open porosity, bulk density and pore morphology of carbon foam were discussed, respectively. The bulk density and true density were tested. The texture of the carbon foams was characterized by scanning electron microscopy. The results show that the pores diameter of carbon foam derived from coal is more uniform, which is in range of 100μm-200μm. Nevertheless, there are a spot of irregular large holes. Foaming temperature is key fact and the suitable foaming temperature must be near to the maximum fluidity temperature of coal. With the foaming pressure increasing, the open porosity reduces, the bulk density increases and the pores diameter gets smaller and more regular.
48
Zhang, Weiqing, Shuguang Jiang, Christopher Hardacre, Peter Goodrich, Kai Wang, Hao Shao, and Zhengyan Wu. "A Combined Raman Spectroscopic and Thermogravimetric Analysis Study on Oxidation of Coal with Different Ranks." Journal of Analytical Methods in Chemistry 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/306874.
Full textAbstract:
Raman spectroscopy and nonisothermal thermogravimetric analysis (TGA) measurements have been reported for different rank coals (lignite, bituminous coal, and anthracite) and the relationship between the measurements was examined. It was found that the Raman spectra parameters can be used to characterize structure changes in the different rank coals, such as the band area ratios based on the curve-fitted results. Higher ranked coal was found to have higher values ofIGR/IAllandIG+GR/IAllbut lower values ofID/I(G+GR),IDL/I(G+GR),IS+SL/I(G+GR), andI(GL+GL')/I(G+GR). The oxidation properties of the coal samples were characterized by the reactivity indexesTig,T20%, andTmaxfrom TGA data which were found to correlate well with the band area ratios ofIGR/IAll,IG+GR/IAll, andIS+SL/I(G+GR). Based on these correlations, the Raman band area ratios were found to correlate with the oxidation activity of coal providing additional structural information which can be used to understand the changes in the TGA measurements.
49
Liu, Yanfei, Song Li, Dazhen Tang, Hao Xu, Shu Tao, Xiong Hu, Xueguang Zhu, and Liang Ma. "Mechanical behavior of low-rank bituminous coal under compression: An experimental and numerical study." Journal of Natural Gas Science and Engineering 66 (June 2019): 77–85. http://dx.doi.org/10.1016/j.jngse.2019.03.012.
Full text
50
Zhao, Hongyu, Yuhuan Li, Qiang Song, Junxin Lv, Yuanfeng Shu, Xinxing Liang, and Xinqian Shu. "Effects of Iron Ores on the Pyrolysis Characteristics of a Low-Rank Bituminous Coal." Energy & Fuels 30, no. 5 (April 22, 2016): 3831–39. http://dx.doi.org/10.1021/acs.energyfuels.6b00061.
Full text