Maceral Association in Coal-bearing Formation of Mae Than Coal Mine in Lampang, Thailand - Implication for Depositional Environment

The Mae Than Basin in Lampang Province contains low-ranked coal reserves of northern Thailand. Coal seams and ball clays were mined in the southern part of the basin. This study focuses on the coal petrography of coal samples collected from the upper coal seam in the Mae Than Coal Mine. Both the organic and inorganic constituents provide information on the nature and characteristics of the coal, reflecting the physical and chemical behaviors of coal. Petrological analysis reveals that the Mae Than coals contain more huminite than liptinite macerals, while inertinite is negligible. Huminite occurs mainly in the form of texto-ulminite, textinite, densinite, and gelinite. Liptinite consists of sporinite, cutinite, resinite, suberinite, liptodetrinite, and terpenite. The morphology of cutinite, sporinite, and the presence of terpenite indicate that the peat-forming vegetation may consist of conifers. In addition to the macerals, the coal samples contain a small to moderate amount of mineral matter. Silica and clay minerals are the main minerals found in the cavities and between the cracks of the coals. The assemblage of macerals and mineral matter indicates that the Mae Than coals were formed mainly from common peat-forming vegetation, possibly conifers, in a freshwater forest swamp or mire in a warm temperate climate. In addition, the high degree of preservation of the macerals indicates a high water table and suggests rheotrophic, anoxic, limnotelmatic to telmatic conditions during deposition.

INNOVATIVE COMPUTERIZED METHODSWITH OPERATIONS RESEARCHTO IMPROVE INDIAN COAL MINING

Because of geological incongruities of reserves, planning and operations of mines are different in each case. A research study was done from IIT(ISM) Dhanbad for developing computerized method studies for better performance and monitoring of a coal company. The research has also developed models for cost-benefit analysis of improved systems of mining operations on ground realities and database creation. The researchwas carried out by analyzing existing mines for developing model programsfor improvements. India has 320 billion tonnes of coal reserves and it is 7 percent of the reserve of the world. The energy consumption in India is about one-third of the world average and 60 percent of the installed capacity of energy in the country is based on thermal plants.The research has developed data-based computer methods in 14 original models; for result-oriented planning for multi-project scheduling and monitoring.Once, the techno-economics of coalmine reorganization is finalized, viz. programs run, scheduling of activities and monitoring for completion become valuable. Research conducted caused better performance and profit for the company.

Effectiveness of carbon active processed from coal in treating the acid mine drainage at a laboratory scale

Low to medium calorie coal reserves dominate Indonesia area. Referring to such amount, the potential for coal synthesis into activated carbon is also massive. The potential utilization of activated carbon from coal to process the acid mine drainage is still developing. This research aims to see the effect of activated carbon to the acid mine drainage from coal mining in a laboratory scale using a weight basis and the contact time between activated carbon and acid mine drainage. The sample is taken from one of the mining locations in East Kalimantan Province. The results showed the effect of the activated carbon weight changes in its pH value, which indicated an increase in pH from 2.19 to a decrease in Fe metal content from 45.2 to 0.1 mg/L and a decrease Mn metal content from 7.22 to 5.3 mg/L. The activated carbon from coal is very effective as an adsorbent for Fe metal but less effective for Mn metal.

Techno-economic analysis study of coal gasification plant into various strategic chemicals

The abundant amount of coal reserves in Indonesia has a great potential to be used as a source of raw materials and energy for industry. However, the use of coal in meeting domestic needs is not optimally utilized, as indicated by the high number of raw coal exports abroad. In addition, the low quality of coal is also one of the reasons for its low utilization. The processing of coal into synthetic gas (syngas) opens the way downstream of coal-derived chemical products, namely dimethyl ether (DME), methanol, ammonia and synthetic natural gas (SNG). The integration of various chemical products is expected to maximize the potential of Indonesian coal. The plant capacity was 11540 tpd (tons per day) low-rank wet coal producing DME 2000 tpd, methanol 2500 tpd, ammonia 600 tpd and SNG 25 MMSCFD (million standard cubic feet per day). These chemical production technologies have been proven and are commercially available. Based on the results of the process and economic simulations, it is found that the establishment of a coal gasification plant into various integrated chemicals is feasible to be established with an internal rate of return (IRR) of 12.46% and a payback period of 6 years and 5 months.

Analysis of the Influence Characteristics of the Support Stability of a Fully Mechanized Coal Mining Face under the Hard Roof Mining Pressure

The conditions of the hard roof in my country vary greatly, ranging from a few meters to tens of meters or even hundreds of meters in thickness. The coal reserves under the hard roof account for about one-third of the total reserves. At present, nearly 40% of fully mechanized mining faces that belong to the hard roof working face has the problem of mining in the hard roof working face. This has a serious impact on the load-bearing stability of the fully mechanized support, and it is urgent to solve the problem of strong underground pressure dynamic disaster under the condition of the hard roof. Based on the research background of 11129 working face in Zhangji Coal Mine in Huainan, this paper constructs a mechanical model of the interaction between the cantilever beam of the hard roof of the stope and the support and then the force distribution equation of the bearing capacity of the supports at different positions of the roof during the periodical rotation of the working face is obtained, which is combined with numerical simulation and engineering site to verify. The research results show that the bearing stability of the support is significantly affected by factors such as the buried depth H, the roof elastic modulus E, the roof thickness h, and the roof cantilever length l0, but most of the influencing factors belong to the geological occurrence conditions of the coal seam itself. Presplit blasting of the roof in advance can effectively destroy the integrity of the roof itself and reduce the periodic breaking distance, thereby improving the apparent environment of roof rock pressure and reducing the force on the working face support. According to the specific geological environment of the 11129 working face, the cutting plan of the cut hole is given out, along the groove 0∼200 and 200∼700 m of the concrete presplitting blasting. The stent force of the top-cutting section fluctuates in the range of 3360.8–4347.9 kN in the range of control top distance (5275∼6175 mm). The load-bearing pressure of the stent before top-cutting is about 1.8 times of that after top-cutting. The pressure distribution of the hydraulic support in the numerical simulation stope is approximately “Λ” in the middle and the low on the two sides. The simulated value is slightly smaller than the theoretical calculation value. The reason is that the goaf is backfilled during the simulation process, and the roof has a certain ability to bear the load. Real-time understanding of the “roof-support” mechanical relationship can effectively ensure the safe and efficient mining of the 11129 working face and also provide experience for the subsequent mining of group B coal in the later period.

Historical memory of the geology of Antioquia: Emil Grosse and The Carboniferous Tertiary of Antioquia

The Carboniferous Tertiary of Antioquia (TCA), published by Dr. Jakob Emil Grosse in 1926, is one of the most influential scien­tific results of the Ordinance 16 of 1918 of the Honorable Departmental Assembly of Antioquia. The work began with the main objective of quantifying the coal reserves of Antioquia, and showing their surface extension on a scale of 1:50 000, in a region that includes the Arma river to the Puente de Occidente and from the western side of the Cauca River to the Romeral lineament and the plains of Ovejas. As a result, extensive work comprising petrological, structural, and economic geology studies was published in a manuscript published in Spanish and German, plus four attached maps, including coal, gold, silver, kaolin, and carbonate mines, among others. In the present work, the four TCA maps were digitized at a scale of 1:50 000 with Bessel 1841 datum and created a unified file in .kml format, which can be used directly in field trips, via Google Earth on cell phones, tablets, or computers. The metadata associates the information in the TCA with the Servicio Geológico Colombiano for the year 2015. In addition, 480 thin sections were scanned, which were donated by Dr. Grosse to the Escuela Nacional de Minas and today are in the Museum of Geosciences of the Faculty of Mines of the Universidad Nacional de Colombia. The geospatial information contained in each thin section was interpreted and georeferenced, obtaining, as a result, a list with north and west geographic coordinates, in degrees, minutes, and seconds. This unpublished information is available in the supplementary material of this article. Finally, nine field trips were made to the places referenced in 23 photographs of the TCA between 1920 and 1923 to take their current equivalent and thus carry out a multi-temporal analysis of the TCA.

Heat Quality Enhancement and Carbon Dioxide Emissions Reduction from Coal Burning by Combining Low-Ranked Coal with Biomass Waste as A Clean Energy Solution to Achieve Energy Security in Indonesia

Indonesia is the fifth largest coal producer in the world with coal reserves reaching 39.56 billion tonnes. Coal reserves of medium and high quality are expected to be exhausted in 2048, therefore it is necessary to utilize low-ranked coals. Low-ranked coals have a low heating value (<5,100 kcal/kg) and produce greater CO2 emissions compared to medium and high rank coals. One method to increase heating value and reduce CO2 emissions from low-ranked coals is through the Utilization of hybrid coal. Hybrid coal is low quality coal combined with biomass waste and has undergone a pyrolysis process together. The mixing and co-pyrolysis of low-ranked coal with biomass waste such as rice husk, empty palm fruit bunches, and rubber wood with a ratio of 7:3 is known to be able to increase the final product calorific value by 31.10–44.12% and reduce non-neutral CO2 emissions by 15.56–21.31%. The hybrid coal production process is highly prospective to be implemented in Indonesia, especially in Central Java, South Sumatra and South Kalimantan. The payback period from the hybrid coal industry with a production capacity range of 540 thousand to 4.5 million TPY can be achieved in 10–13 years with a net profit range of IDR 137 billion to IDR 493 billion per year and a net present value range of IDR 285 billion to IDR 1.1 trillion.

The future of coal as a transportation fuel

Due to environmental concerns and cost issues, coal is currently being phased out from usage in electricity production. Regardless, there remains a massive stockpile of coal reserves along with a large industrial complex and a robust distribution/processing infrastructure. As such, coal should be considered for usage in other energy areas. Since coal is simply a solid hydrocarbon, it can be converted over for usage as a transportation fuel. The Fischer-Tropsch process that underlies this conversion is well established with some countries like South Africa currently using it at large scales. Unfortunately, this conversion process has a large carbon footprint, even when using carbon capture technology. However, the blending of coal-based fuels with biodiesel has been found to be more carbon neutral than standard diesel or biodiesel alone. Additionally, coal can be used as an alternate to methane for hydrogen production. Given carbon capture technologies and the existing coal infrastructure, these two uses of coal provide opportunities for a sustainable and economical use of coal as a transportation fuel.

Mining industry in Mozambique

At present time,Mozambiqueis called the “Rising Star of South Africa” mainly due to the rapid development of its mining industry. Mineral resources sector ofMozambiqueis one of the most dynamically developing sectors of the country’s economy.China,BrazilandIndiahave recently become the main partners forMozambique. Recently, a number of projects is being implemented in the country, for example, Auroch Minerals Manica Gold in gold production. Increasing coal production is connected with commissioning of the Moatize open pit, which is being developed by Brazilian Vale Company, as well as Benga mining company owned by Indian ICVL consortium. The analysis of the extraction of certain mineral types inMozambiquepresented in the paper demonstrates general picture of mining industry development in the country. The analysis findings allow identifying the causes of negative phenomena in the industry, manifesting themselves in decreasing production of certain types of minerals. For instance, the main reasons for the decline in coal production were dropping labor productivity, deterioration of mining conditions, and depletion of the most accessible coal reserves, extractable by open pit mining. In this regard, development of underground mining methods providing for opening of deep deposits by vertical shaft sets is highly relevant. The experience of the neighboringRepublicofSouth Africashows that, in the mining and geological conditions of the south of the African continent, highspeed shaft sinking methods accelerating deposit development can be successfully applied.