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The Use of Granulation to Reduce Dusting and Manage of Fine Coal

The Use of Granulation to Reduce Dusting and Manage of Fine Coal

The granulated fine coal can be used as a re- placement for aggregates. The mechanical prop- erties of granules made with coal and ash, with a small addition of cement and water, were investi- gated [Yoshimoto et al. 2012]. It was found that the compression strength of granules depends on the type and size of the coal and ashes grains to a slight degree. However, the value of the inter- nal stress in granules significantly depends on the type and size of the material. Solovei et al. [2016] shows the method of fine coal granulation in order to obtain mechanically durable spherical granules with a diameter from 1 mm to 6 mm, 3 mm on
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Investigation and Comparison of Emulsified Diesel Oil and Flomin C 9202 as a Collector in the Beneficiation of Ultra-Fine Coal by Agglo-Flotation

Investigation and Comparison of Emulsified Diesel Oil and Flomin C 9202 as a Collector in the Beneficiation of Ultra-Fine Coal by Agglo-Flotation

Abstract: Modern mechanized mining techniques produce enormous quantities of coal fines. Reagents regime (i.e. reagents usage and reagent type) is an important fundamental factor in the process of recovering and dashing of ultra-fine coals (coal fines). The other factors that are crucial for recovery and the purity of the final product obtained is the nature of the particle size of the solids as well as the adsorption of the reagent on the solid particles surface among others. Coal concentrators and mills have embark on the strategy of establishment fine coal benefaction reagents which are not only cheap but effective and efficient. In this study, the effects of both the Flomin C 9202 and Emulsified light diesel oil are investigated in regards to their performance on the combustible recovery as well as the ash remaining in the clean coal product. The study, further involves grinding the coal sample to obtain the fines sizes, flocculate the fines to get the agglomerates and finally float them, what is commonly referred to as Agglo-flotation. The results for both Flomin C 9202 and emulsified light diesel oil were analyzed and after obtaining the best collector (which in this case was Flomin C 9202) then the flowsheet was there after determined. The batch tests for collector determination showed that the Flomin C 9202 outperformed the emulsified diesel oil, and after conducting two stages flowsheet with the collector (Flomin C9202), the ash content was reduced from 22.78%(original coal sample) to 7.91% while the combustible recovery increased from 77.44% (original coal sample) to 92.85%.
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Ash Depression in Fine Coal Flotation Using a Novel Polymer Aid

Ash Depression in Fine Coal Flotation Using a Novel Polymer Aid

modern full seam mechanized mining, ore handling and preparations [1]. These pro- duced coal fines and ultrafines contain an enormous amount of colloidal-sized, ash- forming minerals due to the admixture of clay minerals and other impurities that would likely disseminate to fine and ultrafine fractions. In the past, coal fines from the mines were discarded or stored in refuse ponds. According to a study conducted by the National Research Center, over 70 - 90 million tons of coal fines were annually depo- sited in refuse ponds in the USA [2]. The fine coal refuse is said to be environmentally harmful, leaching toxins into rivers and streams. The rise of stricter environmental reg- ulations to minimize the pollution of land and water has hastened the need for the cleaning and recovery of discarded coal fines particles. Additionally, improving coal prices and technology have made the recovery of coal fines more viable, as they re- present a notable economic resource base. At present, conventional froth flotation is the only commercially available method for the cleaning and recovering of coal fines [3]. The process utilizes differences in surface wettability between coal particles and ash-forming inorganic matter. However, the coal flotation process has been challeng- ing, problematic and costly due to the slime coating of colloidal mineral matter on the surfaces of coal particles and air bubbles. These slime coatings likely reduce the effec- tiveness of flotation recovery, especially when fine grinding is required. Slimes inhibit bubble-particle attachment and increase reagent consumption due to an increased sol- id/liquid interfacial area, resulting in low coal recovery.
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Amenability Testing of Fine Coal Beneficiation Using Laboratory Flotation Column

Amenability Testing of Fine Coal Beneficiation Using Laboratory Flotation Column

flotation column, it can be concluded that column flotation may be employed to process the low rank coal tested and achieve combustible recoveries in the range of 85% was achievable at ash rejections of 81%. The operating conditions required to achieve this separation has been identified. The performance curve revealed that the optimal size range that yields the best separation was in the range of 60­200 microns which is somewhat finer than that of conventional flotation. Empirical relationships to predict the gas hold-up, and carrying capacity have also been developed which can be used in process control at plant scale operations.
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Performance Prediction of a Pressurized Entrained Flow Ultra Fine Coal Gasifier

Performance Prediction of a Pressurized Entrained Flow Ultra Fine Coal Gasifier

As mentioned earlier, the numerical method is based on a coupled Eulerian-Lagrangian formulation in which the conservation equations of the continuous phase are modeled in Eulerian frame and the coal particle trajectory is predicted in a Lagrangian reference frame. The governing equations for mass, momentum, energy and species of the continuous phase can be transformed into a general transport equation of dependent variable φ , written as follows:

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REMNANT COAL DETECTION SYSTEM FOR COAL TRAIN WAGONS

REMNANT COAL DETECTION SYSTEM FOR COAL TRAIN WAGONS

incurred due to both direct effects such as derailments (or unwanted system down-time to allow for rail cleaning) and also to the consequences of coal cross-contamination, when poorer quality coal is mixed with a higher grade product. This mixing can lead to contractual penalties if the grade of the coal delivered to a customer fails to meet the mine’s export specification. This also has a deleterious effect on the miner’s reputation as a reliable supplier. Finally, the residual coal that is spilled onto rails or that remains in unloaded wagons is prone to drying and dispersal as fine coal dust, which is a major environmental and health issue for towns in the coal mining regions of Australia.
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Fine Grained Propaganda Detection with Fine Tuned BERT

Fine Grained Propaganda Detection with Fine Tuned BERT

Propaganda is a type of informative communica- tion with the goal of serving the interest of the information giver (i.e., the propagandist), and not necessarily the recipient (Jowett and O’donnell, 2018). Recently, Da San Martino et al. compiled a new dataset for training machine learning models, containing labeled instances of several common types of propaganda techniques. Through such fine-grained labels, the authors aim to alleviate the issue of noise arising from classifying at a coarse level, e.g., the whole article, as attempted in previ- ous works on propaganda classification (Barr´on- Cede˜no et al., 2019; Rashkin et al., 2017). Us- ing this dataset, the Fragment Level Classifica- tion (FLC) task of the Fine-Grained Propaganda Detection Challenge in NLP4IF’19 requires de- tecting and classifying textual fragments that cor- respond to at least one of the 18 given propa- ganda techniques (Da San Martino et al., 2019a). For instance, given the sentence “Manchin says
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Coal in India

Coal in India

Energy security in India has been interpreted as a drive towards maximum levels of self-sufficiency, using domestic energy resources of hydrocarbons, bioenergy, other renewables, and even thorium (for use in nuclear power generation). This has led to an over-reliance on government-owned monopolies, and introspective policy making. Moreover, the related challenge of rapidly growing imports of fossil fuels is becoming more prominent. India imports large volumes of oil (India has limited reserves), which until recently has been putting considerable pressure on its current account deficit. Of greater concern to India is the rapid growth in gas and coal imports, because they have large reserves, where the combination of local production and transport issues have prevented output from growing at the same rate as demand. The power sector lacks the diversification of sources that most energy importers consider essential for energy security. This is reflected in the lack of diversification in energy supply sources. Around 83 per cent of India’s thermal coal imports are sourced from Indonesia and 86 per cent of its gas imports are sourced from Qatar. India’s electricity generation quadrupled between 1990 and 2012, to 1130 terawatt hours (TWh). In 2012 India was the world’s third largest electricity producer behind China and the United States, and almost equal to Germany and France combined. However, Indian electricity generators have very high own-use requirements (electricity used at the generation plant), large transmission losses (the electricity lost during transport) in excess of 20 per
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FINE WINE, CHAMPAGNE, PORT & SELECT FINE SPIRITS

FINE WINE, CHAMPAGNE, PORT & SELECT FINE SPIRITS

(a) You are entitled to place prior to the auction a reserve on any lot consigned, being the minimum hammer price at which that lot may be sold Reserves must be reasonable and we[r]

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GRES FINE PORCELLANATO FINE PORCELAIN STONEWARE BLOCK

GRES FINE PORCELLANATO FINE PORCELAIN STONEWARE BLOCK

Resistenza ad alte concentrazioni di acidi e alcali Dichiarare una Classe Declared Class Metodo di prova disponibile Test method available UHA Resistance to staining Resistenza alle mac[r]

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Coal Mine Expert System for Prewarming Of Coal Accidents

Coal Mine Expert System for Prewarming Of Coal Accidents

all coal accidents, the most serious incident is roof accident. Roof accidents are account for over 45% of the total mortality in coal enterprises. Roof accident is threatening the lives and safety of miners, and seriously affects the output of enterprises and economic benefits. Industrial Ethernet has been developed based on the roof abscission layer computer monitoring system. The displacement sensor can monitor the location of roof abscission layer. Through the speed displacement changes we can master the roof movement dynamic process .With the help of expert system of the roof forecasting, the workers may get early warning. A great number of facts have proved that the monitoring system has achieved the targets of the design requirements. Its successful application in coal enterprises can promote production safely and efficiently, and have brought remarkable economic and social benefits.
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A review on coal-to-liquid fuels and its coal consumption

A review on coal-to-liquid fuels and its coal consumption

Conversion ratios for CTL are generally estimated to be between 1 and 2 barrels/ton coal. This puts a strict limitation on future CTL capacity imposed by future coal production volumes, regardless of other factors such as economics, emissions or environmental concerns. Assuming that 10% of world coal production can be diverted to CTL, the contribution to liquid fuel supply will be limited to only a few mega barrels per day. This prevents CTL from becoming a viable mitigation plan for liquid fuel shortage on a global scale. However, it is still possible for individual nations to derive significant shares of their fuel supply from CTL, but those nations must also have access to equally significant coal production capacities. It is unrealistic to claim that CTL provides a feasible solution to liquid fuels shortages created by peak oil. For the most part, it can only be a minor contributor and must be combined with other strategies. Copyright r 2009 John Wiley & Sons, Ltd.
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Coal, coal mining and the enterprise culture : a study of Doncaster

Coal, coal mining and the enterprise culture : a study of Doncaster

In exploring political lock-in, this study limits itself to highlighting examples of policy decisions which played a significant role in determining the trajectory of the UK coal industr[r]

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Thermal Processing of Coal in the Plasma Pulverized-Coal Burner

Thermal Processing of Coal in the Plasma Pulverized-Coal Burner

The article presents a description of the plasma pulverized-coal burner developed in a scientific laboratory “of plasma and plasma technologies physics” for the ignition of pulverized coal stream using the low-temperature plasma, key results of the calculations under the programs “Terra” and “Plazmaugol”, results of experimental investigations and test results of the burner prototypes on a heating boiler. Plasma pulverized-coal burner is built under the non-scroll principle and is used to replace mazut in the technological process for the energy of the low-temperature plasma generated in the plasmatron. The non-scroll principle is implemented in the burner through the air- and-fuel mixture is supplied tangentially to the longitudinal axis of the burner. Thereby the supplied in such a way pulverized coal blend is twisting and spiraling without using special devices such as a scroll. The replacement of mazut is carried out because of the partial gasification and heating up to a temperature of the self-ignition of the pulverized coal flow. When going out from the burner the flow is mixing with the secondary air and then is ignited. However the released calorific energy is sufficient to maintain the pulverized coal blend flame combustion and the boiler unit kindling.
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Study on catastrophe of coal and gas outburst in coal tunneling face

Study on catastrophe of coal and gas outburst in coal tunneling face

(2) Stress Stagnation Phenomenon. The moving speed of coal mining floor slows down or even stops during the working face of the coal lane tunneling advanced when some kinds of geologic structures have been caused damage. That the stress concentration belt doesn't move forward is called stress stagnation phenomenon. The precursor information of the stress stagnation phenomenon is that the factor of stress concentration shows an increasing trend, the distressed zone , and that the stress concentrated zone increase not obvious when tunneling advanced; the gas permeability of coal seam will reduce and the gas emission is small at the condition of non tunneling work but the gas emission fluctuates more larger when tunneling .The power is going to gather not far away from the ahead of working face when it comes to stress stagnation phenomenon and it will cause coal and gas outburst easily .The gas pressure of stress concentrated zone is higher and the pressure gradient magnifies at the ahead of tunneling face at the moment.
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Fine Arts JJC Fine Arts Events Calendar

Fine Arts JJC Fine Arts Events Calendar

April 24 3 p.m. Faculty Artist Concert: Rich Moore*, clarinet About Musica Viva For years, the JJC Musica Viva Concert Series has brought high-quality musical offerings to the college and surrounding communities. Typically held at 3 p.m. on various Sundays throughout the fall and spring semesters at the College’s Main Campus (unless otherwise noted) in the Fine Arts Theatre, the series has featured both national and international guests, JJC faculty, graduate students and JJC alumni. For the 2015-2016 season, Musica Viva has scheduled seven performances, including a Cajun band concert preceded by a New Orleans brunch; a concert by a professional choral ensemble held in a spectacular downtown Joliet church; and a harpsichord chamber music concert held in JJC’s Laura A. Sprague Art Gallery.
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Review of coal and gas outburst in Australian underground coal mines

Review of coal and gas outburst in Australian underground coal mines

results to the desorbable gas content threshold values [6,16] . The gas content threshold values proposed by Lama, for both des- orbable and total gas content, are presented in Table 4 . In 1992, the NSW Chief Inspector of Coal Mines (CICM), con- cerned about the increasing number of outburst incidents, as indi- cated by the data presented in Fig. 4 , formed specialist work groups to identify the regional characteristics of outbursts and develop the most appropriate means of protecting mine workers [10,28] . The working group identified the need for management plans, and all mines operating in the Bulli seam were requested to prepare out- burst management plans to specify how they would manage out- burst risk [10,28] . The objective of the NSW Department of Mineral Resources (DMR) was that all Southern Coalfield mines would be operating under auditable outburst management plans
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Should Coal Replace Coal? Options for the Irish Electricity Market

Should Coal Replace Coal? Options for the Irish Electricity Market

Some of the technologies we consider in this study have highly uncertain costs. The lack of commercially-developed CCS plants around the world means that over time, as the technology matures, uncertainty around its costs will decrease. Moreover, while future natural gas prices will always be volatile, the expansion (or not) of shale gas will strongly influence the cost of natural gas. Cheaper future natural gas prices would obviously make the natural gas powered option more attractive. The uncertainty around the construction costs of coal plants with CCS and the prices of natural gas and carbon dioxide permits are likely to decrease significantly in a few years. This makes delaying the Moneypoint replacement decision a potentially appealing option. For every additional year the ‘old’ Moneypoint runs, system costs would be higher. The current plant has a lower efficiency (at 34 per cent) and a total generation capacity of about 850MW. 6 We assume that the O&M costs per MW are the same as for a new PC plant, although this might underestimate the O&M costs of an older plant. The following table shows how much short-run yearly costs (i.e. yearly costs excluding capital costs) change compared to the CCGT and the new PC plant options, which are chosen as comparisons since both have reliable construction costs.
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A REVIEW ON DEVELOPMENT OF CLEAN COAL TECHNOLOGIES AND APPLICATION TO INDIAN COAL

A REVIEW ON DEVELOPMENT OF CLEAN COAL TECHNOLOGIES AND APPLICATION TO INDIAN COAL

Accordingly IICT had procured about 2000 tons of NKP coal. Extensive experimental programmes with varying parameters like Steam/Oxidant ratio in the gasifying medium, Operating Pressure, etc., with a choice of oxidant between Air and pure Oxygen were executed and the data collected during the best operating conditions were evaluated for scale up. Based on the above data from the 24-tpd pilot gasifier of IICT, Hyderabad and also the data from the 150 tpd BHEL unit at Trichy, the dynamic similarity between the two units could be established. llCT's data was scaled up to suit the production of fuel gas required to generate 600MWe of power through IGCC, in collaboration with PDIL (Sindri) for assessing the performance of Moving bed gasification process when using high ash North Karanpura coal from Bihar. The above study became a part of the Techno-Economic Feasibility Report (TEFR) for a 600 MWe conceptual IGCC plant prepared by M/S. Bechtel Corporation, USA for the U.S. processes (Shell, Texaco and KRW) and was compared with that for a conventional PC plant (NTPC) with and without FGD. The Techno-economic Assessment concluded as under:
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Coal petrology and genesis of Jurassic coal in the Ordos Basin, China

Coal petrology and genesis of Jurassic coal in the Ordos Basin, China

Abstract Multiple sets of thick coal beds characterized by simple structure and shallow burial depth were developed in the Early and Middle Jurassic strata of the Ordos Basin, northwestern China. The huge reserves of this high quality coal have a high commercial value. We studied the coal’s petrologic characteristics and its maceral distribution to determine the maceral’s contribution to generation of oil and gas. The results show that the Jurassic coals in the Ordos Basin have special petrological features because of the Basin’s unique depo- sitional environment which was mainly a series of high-stand swamps in the upper fluvial system. These petro- graphic features are a result of the development of typical inland lakes where some sand bodies were formed by migrating rivers. After burial, the peat continued to undergo oxidizing conditions, this process generated extensive higher inertinite contents in the coals and the vitrinite components were altered to semi-vitrinite. The macroscopic petrographic types of these Jurassic coals are mainly semi-dull coal, dull coal, semilustrous and lustrous coal. The proportions of semi-dull coal and dull coal are higher in the basin margins, especially in the area near the northern margin. The numbers of semilustrous and lustrous coals increase southwards and towards the central basin. This situation indicates that different coal-forming swamp environments have major controlling effects on the coal components. Another observation is that in the Ordos’ coal sequences, espe- cially in the lower part, some sandstone beds are thick, up to 20 m with a coarse grain size. The higher fusinite
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