WorldWideScience

Sample records for coal surface properties

  1. Study on surface morphology and physicochemical properties of raw and activated South African coal and coal fly ash

    Science.gov (United States)

    Mishra, S. B.; Langwenya, S. P.; Mamba, B. B.; Balakrishnan, M.

    South African coal and coal fly ash were selected as the raw materials to be used for study of their morphology and physicochemical properties and their respective activated carbons for adsorption applications. Coal and fly ash were individually steam activated at a temperature range of 550-1000 °C for 1 h in a muffle furnace using cylindrical stainless steel containers. Scanning electron micrographs revealed a change in surface morphology with more mineral matter available on the surface of the coal particles due to increased devolatilization. However, in the case of fly ash, the macerals coalesced to form agglomerates and the presence of unburnt carbon constituted pores of diameter between 50 and 100 nm. The BET surface area of coal improved significantly from 5.31 to 52.12 m 2/g whereas in case of fly ash the surface area of the raw sample which was originally 0.59 m 2/g and upon activation increased only up to 2.04 m 2/g. The chemical composition of the fly ash confirmed that silica was the major component which was approximately 60% by weight fraction. The impact of this study was to highlight the importance of using raw materials such as coal and a waste product, in the form of coal ash, in order to produce affordable activated carbon that can be used in drinking water treatment. This would therefore ensure that the quality of water supplied to communities for drinking is not contaminated especially by toxic organic compounds.

  2. Modeling electrochemical resistance with coal surface properties in a direct carbon fuel cell based on molten carbonate

    Science.gov (United States)

    Eom, Seongyong; Ahn, Seongyool; Kang, Kijoong; Choi, Gyungmin

    2017-12-01

    In this study, a numerical model of activation and ohmic polarization is modified, taking into account the correlation function between surface properties and inner resistance. To investigate the correlation function, the surface properties of coal are changed by acid treatment, and the correlations between the inner resistance measured by half-cell tests and the surface characteristics are analyzed. A comparison between the model and experimental results demonstrates that the absolute average deviations for each fuel are less than 10%. The numerical results show that the sensitivities of the coal surface properties affecting polarization losses change depending on the operating temperature. The surface oxygen concentrations affect the activation polarization and the sensitivity decreased with increasing temperature. The surface ash of coal is an additional index to be considered along with ohmic polarization and it has the greatest effect on the surface properties at 973 K.

  3. Surface chemical problems in coal flotation

    Science.gov (United States)

    Taylor, S. R.; Miller, K. J.; Deurbrouck, A. W.

    1981-02-01

    As the use of coal increases and more fine material is produced by mining and processing, the need for improved methods of coal beneficiation increases. While flotation techniques can help meet these needs, the technique is beset with many problems. These problems involve surface chemical and interfacial properties of the coal-mineral-water slurry systems used in coal flotation. The problems associated with coal flotation include non-selectivity, inefficient reagent utilization, and excessive variablity of results. These problems can be broadely classified as a lack of predictability. The present knowledge of coal flotation is not sufficient, in terms of surface chemical parameters, to allow prediction of the flotation response of a given coal. In this paper, some of the surface chemical properties of coal and coal minerals that need to be defined will be discussed in terms of the problems noted above and their impact on coal cleaning.

  4. Surface chemical properties of novel high surface area solids synthesized from coal fly ash

    CSIR Research Space (South Africa)

    Pretorius, PJ

    2003-07-23

    Full Text Available The zeolite, Na-P1, was synthesized from fly ash samples originating from coal-fired power stations in South Africa by hydrothermal treatment of the raw ash with concentrated aqueous NaOH solutions. The zeolite was then further modified by acid...

  5. Properties of sorbents from brown coal

    Energy Technology Data Exchange (ETDEWEB)

    Straka, P.; Buchtele, J. [Academy of Sciences of the Czech Republic, Prague (Czech Republic)

    2000-07-01

    The surface and sorptional properties of carbonaceous materials prepared from brown coal and their relation to minerals content and coal bulk density as technologically important parameters of starting coal were described. Chars were prepared from brown coal of North Bohemian Brown Coal District and activated with CO{sub 2} in a large-scale laboratory unit. Their surface and sorptive properties were investigated. It was found that mineral matter/ash content favourably affects the mesoporosity development in chars/activated chars as the sorption capacity increased with increasing ash content in chars. No influence of ash content on the macroporosity was observed. With the activated chars, both the inner surface and sorption capacity showed the maximum in the burn-off range of 41-64%. Optimization of the process is discussed.

  6. Relation between particle size and properties of some bituminous coals

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, A.D.; Cheng, M.; Goulet, J.-C.; Furimsky, E. (CANMET, Ottawa, ON (Canada). Energy Research Laboratories)

    1990-02-01

    Coal fractions of different size distributions exhibited different H/C ratio, ash and sulphur contents, and surface structures. This was confirmed using two low-sulphur and two high-sulphur bituminous coals. The effect was much less pronounced for low-sulphur coals than for high-sulphur coals. A significant difference in properties was noted between the two high-sulphur coals in spite of similar basic compositional parameters. This was confirmed by the fractal dimensionality factor D of Illinois No. 6 coal, which exceeded the theoretical value. 14 refs., 9 figs., 5 tabs.

  7. Coal surface control for advanced physical fine coal cleaning technologies

    Energy Technology Data Exchange (ETDEWEB)

    Morsi, B.I.; Chiang, S.H.; Sharkey, A.; Blachere, J.; Klinzing, G.; Araujo, G.; Cheng, Y.S.; Gray, R.; Streeter, R.; Bi, H.; Campbell, P.; Chiarlli, P.; Ciocco, M.; Hittle, L.; Kim, S.; Kim, Y.; Perez, L.; Venkatadri, R.

    1992-01-01

    This final report presents the research work carried out on the Coal Surface Control for Advanced Physical Fine Coal Cleaning Technologies project, sponsored by the US Department of Energy, Pittsburgh Energy Technology Center (DOE/PETC). The project was to support the engineering development of the selective agglomeration technology in order to reduce the sulfur content of US coals for controlling SO[sub 2] emissions (i.e., acid rain precursors). The overall effort was a part of the DOE/PETCs Acid Rain Control Initiative (ARCI). The overall objective of the project is to develop techniques for coal surface control prior to the advanced physical fine coal cleaning process of selective agglomeration in order to achieve 85% pyrite sulfur rejection at an energy recovery greater than 85% based on run-of-mine coal. The surface control is meant to encompass surface modification during grinding and laboratory beneficiation testing. The project includes the following tasks: Project planning; methods for analysis of samples; development of standard beneficiation test; grinding studies; modification of particle surface; and exploratory R D and support. The coal samples used in this project include three base coals, Upper Freeport - Indiana County, PA, Pittsburgh NO. 8 - Belmont County, OH, and Illinois No. 6 - Randolph County, IL, and three additional coals, Upper Freeport - Grant County- WV, Kentucky No. 9 Hopkins County, KY, and Wyodak - Campbell County, WY. A total of 149 drums of coal were received.

  8. Relation between coal rank, char reactivity, textural properties and NO emissions

    Energy Technology Data Exchange (ETDEWEB)

    Arenillas, A.; Rubiera, F.; Parra, J.B.; Pis, J.J. [Instituto Nacional del Carbon, Oviedo (Spain)

    1999-07-01

    A low volatile bituminous coal was pyrolysed at different heating rates to produce chars with different textural properties. There was a linear relationship between char reactivity and active surface area. The effect of coal rank on coal char textural properties was studied using a range of bituminous coals. The influence of textural properties and reactivity on NO emissions, and on the heterogeneous reduction of NO is discussed. 6 refs., 2 figs., 2 tabs.

  9. Health status of anthracite surface coal miners

    International Nuclear Information System (INIS)

    Amandus, H.E.; Petersen, M.R.; Richards, T.B.

    1989-01-01

    In 1984-1985, medical examinations consisting of a chest radiograph, spirometry test, and questionnaire on work history, respiratory symptoms, and smoking history were administered to 1,061 white males who were employed at 31 coal cleaning plants and strip coal mines in the anthracite coal region of northeastern Pennsylvania. The prevalence of radiographic evidence of International Labour Office (ILO) category 1 or higher small opacities was 4.5% in 516 men who had never been employed in a dusty job other than in surface coal mining. Among these 516 workers, all 4 cases of ILO radiographic category 2 or 3 rounded opacities and 1 case of large opacities had been employed as a highwall drill operator or helper. The prevalence of category 1 or higher opacities increased with tenure as a highwall drill operator or helper (2.7% for 0 y, 6.5% for 1-9 yr, 25.0% for 10-19 y, and 55.6% for greater than or equal to 20 y drilling). Radiographic evidence of small rounded opacities, dyspnea, and decreases in FEV1.0, FVC, and peak flow were significantly related to tenure at drilling operations after adjusting for age, height, cigarette smoking status, and exposures in dusty jobs other than in surface coal mining. However, tenure in coal cleansing plants and other surface coal mine jobs were not related to significant health effects. The apparent excess prevalence of radiographic small rounded opacities in anthracite surface coal mine drillers suggests that quartz exposures have been increased. Average respirable quartz concentrations at surface coal mine drilling operations should be evaluated to determine whether exposures are within existing standards, and dust exposures should be controlled

  10. Effect of coal soluble constituents on caking property of coal

    Energy Technology Data Exchange (ETDEWEB)

    Hengfu Shui; Mingdong Zheng; Zhicai Wang; Xunming Li [Anhui University of Technology, Maanshan (China). School of Chemistry and Chemical Engineering, Key Laboratory of Anhui Educational Department

    2007-07-15

    Three cokemaking bituminous coals were extracted by the CS{sub 2}/NMP mixed solvents with different content of NMP, and the effect of the amount and the component of coal soluble constituents on the caking property of the extracted residues of coals were investigated in this study. The CS{sub 2}/NMP mixed solvent (1:1 by volume) was found to give the maximal extraction yields for the three coals, and the fat coal gave the highest extraction yield of 78.6% (daf) corresponding to its highest caking index of 101. It was found that for coking coal, when the extraction yield got to the maximum of 25.3% in the 1:1 by volume of CS{sub 2}/NMP mixed solvent, the residue extracted still had caking property with the caking index of 19. This means parts of the caking constituents of coal are un-extractible because of covalent bonding or strong associative cross-links. The soluble components extracted by the CS{sub 2}/NMP mixed solvent and their effects on the caking indexes of the residues at a similar extraction yield quite differed depending on the NMP content in the mixed solvent. The coal solubles extracted by the CS{sub 2}/NMP mixed solvent with NMP less than 50% contained less light constituents with less of oxygen groups. This may lead to the decrease in the caking indexes for the residues obtained at the similar extraction yields compared to those of the CS{sub 2}/NMP mixed solvent with NMP more than 50%. 11 refs., 5 figs., 3 tabs.

  11. Sequestration of carbon dioxide – influence of coal surface chemistry

    Directory of Open Access Journals (Sweden)

    Orzechowska-Zięba Agnieszka

    2016-01-01

    Full Text Available The physical gas adsorption is a widely used method for the characterisation of the solids porosity. The water steam, primarilydue to its physicochemical properties and ease of use in the experiment has great potential as a sorbate. When applied to coal, water steam allows to determine the quantity of primary adsorption centers as measurement of interaction of molecules adsorbed to the surface of the adsorbent. In order to determine the adsorption capacity and the chemical nature of the coal surface, adsorption / desorption of water vapour to the selected coals was examined at 303K, using a volumetric method. The presence of water in the coal may affect on the sorption properties of other molecules. The analysis of the results show that the coals of low rank and a high content of oxygen functional groups, which are the active sites, showed a greater affinity to absorbing water molecules. Adsorption isotherms were compiled through approximating the Langmuir and BET linear equation to measurement data. Based on the adsorption equation, the amount of adsorption centers have been specified, which can potentially be involved in the adsorption of CO2 during the injection of gas into the coal seams.

  12. Multivariate statistical assessment of coal properties

    Czech Academy of Sciences Publication Activity Database

    Klika, Z.; Serenčíšová, J.; Kožušníková, Alena; Kolomazník, I.; Študentová, S.; Vontorová, J.

    2014-01-01

    Roč. 128, č. 128 (2014), s. 119-127 ISSN 0378-3820 R&D Projects: GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : coal properties * structural,chemical and petrographical properties * multivariate statistics Subject RIV: DH - Mining, incl. Coal Mining Impact factor: 3.352, year: 2014 http://dx.doi.org/10.1016/j.fuproc.2014.06.029

  13. How Selby coal will reach the surface

    Energy Technology Data Exchange (ETDEWEB)

    1979-11-01

    In many respects this conveyor will exemplify the NCB's intention to employ the latest technology at Selby. This single conveyor will be almost 15km long, and will bring coal to the surface from almost 1 km below ground level. A steel cord belt, 1300 mm wide and weighing over 2500 tonnes, will travel at up to 8.4 m/s to bring as much as 3200 t/h of coal to the surface. The conveyor is capable of delivering up to 1800 t/h of coal even from the furthest and deepest point in the conveyor run. Maximum tension in the belt is almost 200 tonnes, and even on the slack side of the pulley, the tension will be 68 tonnes. Eleven bunkering points will each be capable of feeding 750 tonnes of coal per hour, and a computerized control will ensure that the required mix is brought from the bunkers without exceeding the maximum capacity of the conveyor. When maximum tonnage is not being handled, the conveyor will be capable of running at the lowest speed which is capable of bringing out the tonnage on the belt. This minimizes wear and tear on all moving parts of the system. From each bunkering point, the coal will be fed down a chute onto a short accelerating conveyor which feeds the coal centrally onto the main conveyor and ensures that it is moving in the same direction as the main conveyor.

  14. Coal surface structure and thermodynamics. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, J.W.; Wernett, P.C.; Glass, A.S.; Quay, D.; Roberts, J.

    1994-05-01

    Coals surfaces were studied using static surface adsorption measurements, low angle x-ray scattering (LAXS), inverse gas chromatography (IGC) and a new {sup 13}C NMR relaxation technique. A comparison of surface areas determined by hydrocarbon gas adsorption and LAXS led to the twin conclusions that the hydrocarbons had to diffuse through the solid to reach isolated pores and that the coal pores do not form interconnected networks, but are largely isolated. This conclusion was confirmed when IGC data for small hydrocarbons showed no discontinuities in their size dependence as usually observed with porous solids. IGC is capable of providing adsorption thermodynamics of gases on coal surfaces. The interactions of non-polar molecules and coal surfaces are directly proportioned to the gas molecular polarizability. For bases, the adsorption enthalpy is equal to the polarizability interaction plus the heat of hydrogen bond formation with phenol. Amphoteric molecules have more complex interactions. Mineral matter can have highly specific effects on surface interactions, but with most of the molecules studied is not an important factor.

  15. Surface characterisation of synthetic coal chars made from model compounds

    Energy Technology Data Exchange (ETDEWEB)

    Arenillas, A.; Pevida, C.; Rubiera, F.; Palacios, J.M.; Navarrete, R.; Denoyel, R.; Rouquerol, J.; Pis, J.J. [Instituto Nacional del Carbon, CSIC, Oviedo (Spain)

    2004-07-01

    Knowledge of surface properties is essential for understanding the reaction mechanisms involved in several coal conversion processes. However, due to the complexity and heterogeneity of coal this is rather difficult and the use of known model compounds could be a valuable tool. Single model compounds have been widely used, but they give a quite simplified picture. In this work a mixture of model compounds in a phenol-formaldehyde matrix was cured in order to create cross-linked structures. The obtained synthetic coal was pyrolysed in a fixed bed reactor, under helium atmosphere. The surface composition of the chars was evaluated by XPS, adsorption gravimetry of water vapour, temperature-programmed desorption and potentiometric titration. Texture was characterised by N{sub 2} and CO{sub 2} adsorption isotherms at 77 and 273 K, respectively, and immersion calorimetry in benzene. The results obtained from the different techniques were contrasted in order to give an overview of the surface properties (chemical and physical) of the samples studied. Chars obtained under the same operating conditions from a high volatile bituminous coal were used as a reference.

  16. Energy characteristics of finest coal particles surfaces versus their upgrading using flotation

    Energy Technology Data Exchange (ETDEWEB)

    Jerzy Sablik

    2007-07-01

    The paper presents selected results of investigations on energy properties of the fine coal particles, and methodological grounds for conducting such investigations. Using the discussed relationships, values of contact angle of coal particles with various degree of coalification in the range defined by the energy nonhomogeneity of the surfaces were computed. There have been determined the values of the contact angles of coal particles with hydrophobic and hydrophilic surfaces after coating with nonpolar and polar reagents. The energy state of the surfaces of coal particles in the feeds and products of industrial flotation were determined, which enabled to evaluate this process. 22 refs., 6 figs., 4 tabs.

  17. Baking and coking properties of hard coal under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Beyer, H.D.

    1981-09-01

    For a better assessment of the baking and coking properties of hard coal under high pressure as in modern coal beneficiation processes, the determination of the swelling index and the dilatation curve are investigated.

  18. Experimental Investigation of Coal Dust Wettability Based on Surface Contact Angle

    Directory of Open Access Journals (Sweden)

    Gang Zhou

    2016-01-01

    Full Text Available Wettability is one of the key chemical properties of coal dust, which is very important to dedusting. In this paper, the theory of liquid wetting solid was presented firstly; then, taking the gas coal of Xinglongzhuang coal mine in China as an example, by determination of critical surface tension of coal piece, it can be concluded that only when the surface tension of surfactant solution is less than 45 mN/m can the coal sample be fully wetted. Due to the effect of particle dispersity, compared with the contact angle of milled coal particle, not all the contact angles of screened coal powder with different sizes have a tendency to increase. Furthermore, by the experiments of coal samples’ specific surface areas and porosities, it can be achieved that the volume of single-point total pore decreases with the gradual decreasing of coal’s porosity, while the ultramicropores’ dispersities and multipoint BET specific surface areas increase. Besides, by a series of contact angle experiments with different surfactants, it can be found that with the increasing of porosity and the decreasing of volume percentage of ultramicropore, the contact angle tends to reduce gradually and the coal dust is much easier to get wetted.

  19. Physical and performance properties of coal tar urethanes - pipe

    International Nuclear Information System (INIS)

    Hickney, J.; Hendry, M.

    1984-01-01

    The purpose of this paper is to review certain physical properties of coal tar extended urethane coatings designed specifically for use in the pipe coatings market. The blend of coal tar and urethane resins provides a novel finished product with properties cumulatively inherent in its constituents. Typically, coal tar and coal tar pitch offer exceptional water resistance and cathodic alkali resistance when blended with other resins. An example is the standard coal tar epoxies used for many years in the marine markets for shipbottoms

  20. Change in surface characteristics of coal in upgrading of low-rank coals; Teihin`itan kaishitsu process ni okeru sekitan hyomen seijo no henka

    Energy Technology Data Exchange (ETDEWEB)

    Oki, A.; Xie, X.; Nakajima, T.; Maeda, S. [Kagoshima University, Kagoshima (Japan). Faculty of Engineering

    1996-10-28

    With an objective to learn mechanisms in low-rank coal reformation processes, change of properties on coal surface was discussed. Difficulty in handling low-rank coal is attributed to large intrinsic water content. Since it contains highly volatile components, it has a danger of spontaneous ignition. The hot water drying (HWD) method was used for reformation. Coal which has been dry-pulverized to a grain size of 1 mm or smaller was mixed with water to make slurry, heated in an autoclave, cooled, filtered, and dried in vacuum. The HWD applied to Loy Yang and Yallourn coals resulted in rapid rise in pressure starting from about 250{degree}C. Water content (ANA value) absorbed into the coal has decreased largely, with the surface made hydrophobic effectively due to high temperature and pressure. Hydroxyl group and carbonyl group contents in the coal have decreased largely with rising reformation treatment temperature (according to FT-IR measurement). Specific surface area of the original coal of the Loy Yang coal was 138 m{sup 2}/g, while it has decreased largely to 73 m{sup 2}/g when the reformation temperature was raised to 350{degree}C. This is because of volatile components dissolving from the coal as tar and blocking the surface pores. 2 refs., 4 figs.

  1. Selective bibliography of surface coal mining and reclamation literature. Volume 2. Interior Coal Province

    Energy Technology Data Exchange (ETDEWEB)

    Patricoski, M. L.; Daniels, L. K.; Sobek, A. A.

    1979-08-01

    This bibliography has been compiled for use by researchers, students, and other groups who need a reference source of published literature related to surface coal mining and reclamation in the Interior Coal Province. This bibliography contains more than 1300 references, including government reports, journal articles, symposium proceedings, industrial reports, workshop proceedings, theses, and bibliographies. A simple format was used to categorize citations.

  2. Properties of sodium lignosulfonate as dispersant of coal water slurry

    International Nuclear Information System (INIS)

    Yang, Dongjie; Qiu, Xueqing; Zhou, Mingsong; Lou, Hongming

    2007-01-01

    In order to use lignosulfonates (a by-product of pulp and paper processes) as an effective dispersant of coal water slurry five purified sodium lignosulfonate (SL) samples with different molecular weights were prepared by fractionation using ultrafiltration and dialysis. The effect of SL on the apparent viscosity of coal water slurry (CWS) was investigated. The adsorption behavior of the SL on the coal water interface has much greater effect on the viscosity of coal water slurry. The higher adsorption amount and compact adsorption film of SL on the coal surface help reduce the viscosity of CWS, and the zeta potential is also an important factor, which is influenced by the sulfonic and carboxyl group contents of the lignosulfonate molecule. Furthermore, the SL with its molecular weight ranging from 10,000 to 30,000 has both a higher adsorbed amount and zeta potential on the coal surface and the best effect on reducing the viscosity of the coal water slurry

  3. Effect of the surface oxygen groups on methane adsorption on coals

    Energy Technology Data Exchange (ETDEWEB)

    Hao Shixiong [Department of Chemical Engineering, Sichuan University, Chengdu 610065 (China); Department of Chemical Engineering, Sichuan University of Science and Engineering, Zigong 643000 (China); Wen Jie [Department of Chemical Engineering, Sichuan University, Chengdu 610065 (China); Yu Xiaopeng [Department of Chemical Engineering, Sichuan University, Chengdu 610065 (China); Department of Chemical Engineering, Sichuan University of Science and Engineering, Zigong 643000 (China); Chu Wei, E-mail: chuwei1965_scu@yahoo.com [Department of Chemical Engineering, Sichuan University, Chengdu 610065 (China)

    2013-01-01

    Highlights: Black-Right-Pointing-Pointer We modified one coal with H{sub 2}O{sub 2}, (NH{sub 4}){sub 2}S{sub 2}O{sub 8} and HNO{sub 3} respectively, to prepare coal samples with different surface properties. Black-Right-Pointing-Pointer The oxygen groups on coal surface were characterized by XPS. Black-Right-Pointing-Pointer The textures of the coal samples were investigated by N{sub 2} adsorption at 77 K. Black-Right-Pointing-Pointer The adsorption behaviors were measured by volumetric method. Black-Right-Pointing-Pointer There was a negative correlation between methane saturated adsorption capacity and the O{sub total}/C{sub total}. - Abstract: To investigate the influence of surface oxygen groups on methane adsorption on coals, one bituminous coal was modified with H{sub 2}O{sub 2}, (NH{sub 4}){sub 2}S{sub 2}O{sub 8} and HNO{sub 3} respectively, to prepare coal samples with different surface properties. The oxygen groups on coal surface were characterized by X-ray photoelectron spectroscopy (XPS). The textures of the coal samples were investigated by N{sub 2} adsorption at 77 K. Their surface morphologies were analyzed by scanning electron microscopy (SEM). The methane adsorption behaviors of these coal samples were measured at 303 K in pressure range of 0-5.3 MPa by volumetric method. The adsorption data of methane were fitted to the Langmuir model and Dubinin-Astakhov (D-A) model. The fitting results showed that the D-A model fitted the isotherm data better than the Langmuir model. It was observed that there was, in general, a positive correlation between the methane saturated adsorption capacity and the micropore volume of coals while a negative correlation between methane saturated adsorption capacity and the O{sub total}/C{sub total}. The methane adsorption capacity was determined by the coal surface chemistry when the microporosity parameters of two samples were similar. Coal with a higher amount of oxygen surface groups, and consequently with a less

  4. Investigation of the efect of the coal particle sizes on the interfacial and rheological properties of coal-water slurry fuels

    Energy Technology Data Exchange (ETDEWEB)

    Kihm, K.D.; Deignan, P. [Texas A& M Univ., College Station, TX (United States)

    1995-11-01

    Experiments were conducted to investigate the effect of particle size on coal-water slurry (CWS) surface tension properties. Two different coal powder samples of different size ranges were obtained through sieving of coal from the Upper Elkhorn Seam. The surfactant (anionic DDBS-soft, dodecylbenzene sulfonic acid) concentration varied from 0 to 1.0% in weight while the coal loading remained at 40% in weight for all the cases. A du Nouy ring tensiometer and a maximum bubble pressure tensiometer measured the static and dynamic surface tensions, respectively, The results show that both static and dynamic surface tensions tend to increase with decreasing coal particle sizes suspended in CWS fuels. Examination of the peak pressure, minimum pressure, surfactant diffusion time, and dead time were also made to correlate these microscopic pressure behavior with the macroscopic dynamic surface tension and to examine the accuracy of the experiment.

  5. The Effect of Bedding Structure on Mechanical Property of Coal

    Directory of Open Access Journals (Sweden)

    Zetian Zhang

    2014-01-01

    Full Text Available The mechanical property of coal, influencing mining activity considerably, is significantly determined by the natural fracture distributed within coal mass. In order to study the effecting mechanism of bedding structure on mechanical property of coal, a series of uniaxial compression tests and mesoscopic tests have been conducted. The experimental results show that the distribution characteristic of calcite particles, which significantly influences the growth of cracks and the macroscopic mechanical properties of coal, is obviously affected by the bedding structure. Specifically, the uniaxial compression strength of coal sample is mainly controlled by bedding structure, and the average peak stress of specimens with axes perpendicular to the bedding planes is 20.00 MPa, which is 2.88 times the average amount of parallel ones. The test results also show a close relationship between the bedding structure and the whole deformation process under uniaxial loading.

  6. Environmental impact assessment for surface coal mine - a case study

    International Nuclear Information System (INIS)

    Sen, P.; Chakraborty, K.

    1994-01-01

    Surface coal mines being the largest contributor to the national coal production, the study of environmental impacts due to this becomes mandatory as it will help in proper planning and safe operations of the mine in an environmentally compatible manner. Within the scope of this paper, a model for preparation of comprehensive environmental impact assessment (EIA) by utilising a new evaluation methodology leading to determination of Environmental Quality Designation an index has been developed and this model has been validated by using data from a running surface coal mine in Wardha Valley Coalfield. Based on this exercise, the overall impact of the surface coal mine under consideration on environment indicates a medium level and accordingly the control measures have to be planned. Thus repair to the environment has to be made a concurrent activity with mining i.e. to say we have to design with nature not against it

  7. Effects of Coal Gangue on Cement Grouting Material Properties

    Science.gov (United States)

    Liu, J. Y.; Chen, H. X.

    2018-05-01

    The coal gangue is one of the most abundant industrial solid wastes and pollute source of air and water. The use of coal gangue in the production of cement grouting material comforms to the basic state policy of environment protection and the circular using of natural resources. Through coal gangue processing experiment, coal gangue cement grouting materials making test, properties detection of properties and theoretical analysis, the paper studied the effects of coal gangue on the properties of cement grouting materials. It is found that at the range of 600 to 700 °C, the fluidity and the compressive and flexural strengths of the cement grouting materials increase with the rising up of the calcination temperatures of coal gangue. The optimum calcination temperature is around 700 °C. The part substitution of cement by the calcined coal gangue in the cement grouting material will improve the mechanical properties of the cement grouting material, even thought it will decrease its fluidity. The best substitution amount of cement by coal gangue is about 30%. The fluidity and the long term strength of the ordinary silicate cement grouting material is obviously higher than that of the sulphoaluminate cement one as well as that of the silicate-sulphoaluminate complex cement one.

  8. Literature survey of properties of synfuels derived from coal

    Science.gov (United States)

    Reynolds, T. W.; Niedzwiecki, R. W.; Clark, J. S.

    1980-02-01

    A literature survey of the properties of synfuels for ground-based gas turbine applications is presented. Four major concepts for converting coal into liquid fuels are described: solvent extraction, catalytic liquefaction, pyrolysis, and indirect liquefaction. Data on full range syncrudes, various distillate cuts, and upgraded products are presented for fuels derived from various processes, including H-coal, synthoil, solvent-refined coal, donor solvent, zinc chloride hydrocracking, co-steam, and flash pyrolysis. Some typical ranges of data for coal-derived low Btu gases are also presented.

  9. Literature survey of properties of synfuels derived from coal

    Science.gov (United States)

    Reynolds, T. W.; Niedzwiecki, R. W.; Clark, J. S.

    1980-01-01

    A literature survey of the properties of synfuels for ground-based gas turbine applications is presented. Four major concepts for converting coal into liquid fuels are described: solvent extraction, catalytic liquefaction, pyrolysis, and indirect liquefaction. Data on full range syncrudes, various distillate cuts, and upgraded products are presented for fuels derived from various processes, including H-coal, synthoil, solvent-refined coal, donor solvent, zinc chloride hydrocracking, co-steam, and flash pyrolysis. Some typical ranges of data for coal-derived low Btu gases are also presented.

  10. Deposit growth and property development in coal-fired furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L. [Sandia National Lab., Livermore, CA (United States)

    1995-11-01

    The objectives of this research project are: (1) to provide a self-consistent database of simultaneously measured, time-resolved ash deposit properties in well-controlled and well-defined environments and (2) to provide analytical expressions that relate deposit composition and structure to deposit properties of immediate relevance to PETC`s Combustion 2000 program. This project is distinguished from related work being done elsewhere by: (1) the development and deployment of in-situ diagnostics to monitor deposit properties, including heat transfer coefficients, porosity, emissivity, tenacity, strength, density, and viscosity; (2) the time resolution of such properties during deposit growth; (3) simultaneous measurement of structural and composition properties; (4) development of algorithms from a self-consistent, simultaneously measured database that includes the interdependence of properties; and (5) application of the results to technologically relevant environments such as those being planned under Combustion 2000 program. Work completed during FY94 emphasized diagnostic development. During FY95, this development work will be completed and we will emphasize application of the diagnostics to meet the other project objectives. Included in this work are the development and application of two in-situ, real-time diagnostic systems for monitoring the properties of inorganic materials on Heat transfer surfaces and in the gas-phase during controlled combustion of selected coal samples in Sandia`s Multifuel Combustor (MFC). Also, several diagnostics are being incorporated into the MFC that will eventually be used to characterize ash deposit properties.

  11. Coal and Open-pit surface mining impacts on American Lands (COAL)

    Science.gov (United States)

    Brown, T. A.; McGibbney, L. J.

    2017-12-01

    Mining is known to cause environmental degradation, but software tools to identify its impacts are lacking. However, remote sensing, spectral reflectance, and geographic data are readily available, and high-performance cloud computing resources exist for scientific research. Coal and Open-pit surface mining impacts on American Lands (COAL) provides a suite of algorithms and documentation to leverage these data and resources to identify evidence of mining and correlate it with environmental impacts over time.COAL was originally developed as a 2016 - 2017 senior capstone collaboration between scientists at the NASA Jet Propulsion Laboratory (JPL) and computer science students at Oregon State University (OSU). The COAL team implemented a free and open-source software library called "pycoal" in the Python programming language which facilitated a case study of the effects of coal mining on water resources. Evidence of acid mine drainage associated with an open-pit coal mine in New Mexico was derived by correlating imaging spectrometer data from the JPL Airborne Visible/InfraRed Imaging Spectrometer - Next Generation (AVIRIS-NG), spectral reflectance data published by the USGS Spectroscopy Laboratory in the USGS Digital Spectral Library 06, and GIS hydrography data published by the USGS National Geospatial Program in The National Map. This case study indicated that the spectral and geospatial algorithms developed by COAL can be used successfully to analyze the environmental impacts of mining activities.Continued development of COAL has been promoted by a Startup allocation award of high-performance computing resources from the Extreme Science and Engineering Discovery Environment (XSEDE). These resources allow the team to undertake further benchmarking, evaluation, and experimentation using multiple XSEDE resources. The opportunity to use computational infrastructure of this caliber will further enable the development of a science gateway to continue foundational COAL

  12. Dynamic measurement of coal thermal properties and elemental composition of volatile matter during coal pyrolysis

    Directory of Open Access Journals (Sweden)

    Rohan Stanger

    2014-01-01

    Full Text Available A new technique that allows dynamic measurement of thermal properties, expansion and the elemental chemistry of the volatile matter being evolved as coal is pyrolysed is described. The thermal and other properties are measured dynamically as a function of temperature of the coal without the need for equilibration at temperature. In particular, the technique allows for continuous elemental characterisation of tars as they are evolved during pyrolysis and afterwards as a function of boiling point. The technique is demonstrated by measuring the properties of maceral concentrates from a coal. The variation in heats of reaction, thermal conductivity and expansion as a function of maceral composition is described. Combined with the elemental analysis, the results aid in the interpretation of the chemical processes contributing to the physical and thermal behaviour of the coal during pyrolysis. Potential applications in cokemaking studies are discussed.

  13. Structural Characteristics and Physical Properties of Tectonically Deformed Coals

    OpenAIRE

    Yiwen Ju; Zhifeng Yan; Xiaoshi Li; Quanlin Hou; Wenjing Zhang; Lizhi Fang; Liye Yu; Mingming Wei

    2012-01-01

    Different mechanisms of deformation could make different influence on inner structure and physical properties of tectonically deformed coal (TDC) reservoirs. This paper discusses the relationship between macromolecular structure and physical properties of the Huaibei-Huainan coal mine areas in southern North China. The macromolecular structure and pore characteristics are systematically investigated by using techniques such as X-ray diffraction (XRD), high-resolution transmission electron mic...

  14. Mercury distribution in coals influenced by magmatic intrusions, and surface waters from the Huaibei Coal Mining District, Anhui, China

    International Nuclear Information System (INIS)

    Yan, Zhicao; Liu, Guijian; Sun, Ruoyu; Wu, Dun; Wu, Bin; Zhou, Chuncai

    2013-01-01

    Highlights: • Hg concentrations in coal and surface water samples were determined. • Hg is enriched in the Huaibei coals. • Magmatic activities imparted influences on Hg content and distribution. • Hg contents in surface waters are relative low at the present status. - Abstract: The Hg concentrations in 108 samples, comprising 81 coal samples, 1 igneous rock, 2 parting rock samples and 24 water samples from the Huaibei Coal Mining District, China, were determined by cold-vapor atomic fluorescence spectrometry. The abundance and distribution of Hg in different coal mines and coal seams were studied. The weighted average Hg concentration for all coal samples in the Huaibei Coalfield is 0.42 mg/kg, which is about twice that of average Chinese coals. From southwestern to northeastern coalfield, Hg concentration shows a decreasing trend, which is presumably related to magmatic activity and fault structures. The relatively high Hg levels are observed in coal seams Nos. 6, 7 and 10 in the southwestern coal mines. Correlation analysis indicates that Hg in the southwestern and southernmost coals with high Hg concentrations is associated with pyrite. The Hg concentrations in surface waters in the Huaibei Coal Mining District range from 10 to 60 ng/L, and display a decreasing trend with distance from a coal waste pile but are lower than the regulated levels for Hg in drinking water

  15. Coal surface control for advanced physical fine coal cleaning technologies. Final report, September 19, 1988--August 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Morsi, B.I.; Chiang, S.H.; Sharkey, A.; Blachere, J.; Klinzing, G.; Araujo, G.; Cheng, Y.S.; Gray, R.; Streeter, R.; Bi, H.; Campbell, P.; Chiarlli, P.; Ciocco, M.; Hittle, L.; Kim, S.; Kim, Y.; Perez, L.; Venkatadri, R.

    1992-12-31

    This final report presents the research work carried out on the Coal Surface Control for Advanced Physical Fine Coal Cleaning Technologies project, sponsored by the US Department of Energy, Pittsburgh Energy Technology Center (DOE/PETC). The project was to support the engineering development of the selective agglomeration technology in order to reduce the sulfur content of US coals for controlling SO{sub 2} emissions (i.e., acid rain precursors). The overall effort was a part of the DOE/PETCs Acid Rain Control Initiative (ARCI). The overall objective of the project is to develop techniques for coal surface control prior to the advanced physical fine coal cleaning process of selective agglomeration in order to achieve 85% pyrite sulfur rejection at an energy recovery greater than 85% based on run-of-mine coal. The surface control is meant to encompass surface modification during grinding and laboratory beneficiation testing. The project includes the following tasks: Project planning; methods for analysis of samples; development of standard beneficiation test; grinding studies; modification of particle surface; and exploratory R&D and support. The coal samples used in this project include three base coals, Upper Freeport - Indiana County, PA, Pittsburgh NO. 8 - Belmont County, OH, and Illinois No. 6 - Randolph County, IL, and three additional coals, Upper Freeport - Grant County- WV, Kentucky No. 9 Hopkins County, KY, and Wyodak - Campbell County, WY. A total of 149 drums of coal were received.

  16. Average nuclear surface properties

    International Nuclear Information System (INIS)

    Groote, H. von.

    1979-01-01

    The definition of the nuclear surface energy is discussed for semi-infinite matter. This definition is extended also for the case that there is a neutron gas instead of vacuum on the one side of the plane surface. The calculations were performed with the Thomas-Fermi Model of Syler and Blanchard. The parameters of the interaction of this model were determined by a least squares fit to experimental masses. The quality of this fit is discussed with respect to nuclear masses and density distributions. The average surface properties were calculated for different particle asymmetry of the nucleon-matter ranging from symmetry beyond the neutron-drip line until the system no longer can maintain the surface boundary and becomes homogeneous. The results of the calculations are incorporated in the nuclear Droplet Model which then was fitted to experimental masses. (orig.)

  17. Investigation on the Activity Activation and Cementitious Property of Coal Gangue with High Iron and Silica Contents

    Science.gov (United States)

    Wu, Hong; Li, Yu; Teng, Min; Yang, Yu

    2017-11-01

    The activity of coal gangue by thermal activation and composite activation technologies was investigated. The crystal composition, framework structure and morphology change were analyzed by XRD, FT-IR and SEM, respectively. The cementitious property of coal gangue was measured by strength test. The results showed that thermal activation decomposed kaolinite in coal gangue, and formed the metastable structure with a porous state, multiple internal broken bonds and large specific surface areas. Based on thermal activation, the added lime provided the alkaline environment, then this reduced the bond energy of reactant particles and the degree of crystallinity of quartz in coal gangue. The two activation methods could effectively improve the cementitious property of coal gangue based unburned bricks, and that the composite activation technology was superior performance.

  18. Damage to underground coal mines caused by surface blasting

    International Nuclear Information System (INIS)

    Fourie, A.B.; Green, R.W.

    1993-01-01

    An investigation of the potential damage to underground coal workings as a result of surface blasting at an opencast coal mine is described. Seismometers were installed in a worked out area of an underground mine, in the eastern Transvaal region of South Africa, and the vibration caused by nearby surface blasting recorded. These measurements were used to derive peak particle velocities. These velocities were correlated with observed damage underground in order to establish the allowable combination of the two blasting parameters of charge mass per relay, and blast-to-gage point distance. An upper limit of 110mm/sec peak particle velocity was found to be sufficient to ensure that the damage to the particular workings under consideration was minimal. It was further found that a cube-root scaling law provided a better fit to the field data than the common square-root law. 11 refs., 6 figs., 5 tabs

  19. 77 FR 26046 - Proposed Extension of Existing Information Collection; Ground Control for Surface Coal Mines and...

    Science.gov (United States)

    2012-05-02

    ... Extension of Existing Information Collection; Ground Control for Surface Coal Mines and Surface Work Areas of Underground Coal Mines AGENCY: Mine Safety and Health Administration, Labor. ACTION: Request for... inspections and investigations in coal or other mines shall be made each year for the purposes of, among other...

  20. Thermo-optical properties of residential coals and combustion aerosols

    Science.gov (United States)

    Pintér, Máté; Ajtai, Tibor; Kiss-Albert, Gergely; Kiss, Diána; Utry, Noémi; Janovszky, Patrik; Palásti, Dávid; Smausz, Tomi; Kohut, Attila; Hopp, Béla; Galbács, Gábor; Kukovecz, Ákos; Kónya, Zoltán; Szabó, Gábor; Bozóki, Zoltán

    2018-04-01

    In this study, we present the inherent optical properties of carbonaceous aerosols generated from various coals (hard through bituminous to lignite) and their correlation with the thermochemical and energetic properties of the bulk coal samples. The nanoablation method provided a unique opportunity for the comprehensive investigation of the generated particles under well controlled laboratory circumstances. First, the wavelength dependent radiative features (optical absorption and scattering) and the size distribution (SD) of the generated particulate matter were measured in-situ in aerosol phase using in-house developed and customised state-of-the-art instrumentation. We also investigated the morphology and microstructure of the generated particles using Transmission Electron Microscopy (TEM) and Electron Diffraction (ED). The absorption spectra of the measured samples (quantified by Absorption Angström Exponent (AAE)) were observed to be distinctive. The correlation between the thermochemical features of bulk coal samples (fixed carbon (FC) to volatile matter (VM) ratio and calorific value (CV)) and the AAE of aerosol assembly were found to be (r2 = 0.97 and r2 = 0.97) respectively. Lignite was off the fitted curves in both cases most probably due to its high optically inactive volatile material content. Although more samples are necessary to be investigated to draw statistically relevant conclusion, the revealed correlation between CV and Single Scattering Albedo (SSA) implies that climatic impact of coal combusted aerosol could depend on the thermal and energetic properties of the bulk material.

  1. Selective bibliography of surface coal mining and reclamation literature. Volume 1. Eastern coal province. [More than 1300 references

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, N. E.; Sobek, A. A.; Streib, D. L.

    1977-11-01

    This bibliography has been compiled for use by researchers, students, and other groups who need a reference source of published literature related to surface coal mining and reclamation in the Eastern Coal Province. This bibliography contains more than 1300 references including government reports, journal articles, symposium proceedings, industrial reports, workshop proceedings, theses, and bibliographices. A simple format was used to categorize citations.

  2. VLF surface-impedance modelling techniques for coal exploration

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, G.; Thiel, D.; O' Keefe, S. [Central Queensland University, Rockhampton, Qld. (Australia). Faculty of Engineering and Physical Systems

    2000-10-01

    New and efficient computational techniques are required for geophysical investigations of coal. This will allow automated inverse analysis procedures to be used for interpretation of field data. In this paper, a number of methods of modelling electromagnetic surface impedance measurements are reviewed, particularly as applied to typical coal seam geology found in the Bowen Basin. At present, the Impedance method and the finite-difference time-domain (FDTD) method appear to offer viable solutions although both have problems. The Impedance method is currently slightly inaccurate, and the FDTD method has large computational demands. In this paper both methods are described and results are presented for a number of geological targets. 17 refs., 14 figs.

  3. Petrographic properties of major coal seams in Turkey and their formation

    Energy Technology Data Exchange (ETDEWEB)

    Toprak, Selami [Mineral Research and Exploration Directorate (MTA), 06520 Ankara (Turkey)

    2009-06-01

    Most types of coal in Turkey are generally low in rank: lignite, and subbituminous. Most of the coal was formed during the Miocene, Eocene, and Pliocene ages. There are only a few thin Jurassic-age coal occurrences in Turkey. Pennsylvanian age bituminous coal is found on the Black Sea coast. General implications of the petrographic properties of Turkey's coal seams and coal deposits have not yet been taken into consideration comparatively or as a whole. For this study, about 190 channel samples were collected from different locales. The composite profile samples of the seams were taken into considerations. The content and depositional properties as well as some chemical and physical properties of the main coal seams are compared. All coal samples tend to have similar coal petrographic properties and were deposited in intermontane lacustrine basins. Later, they were affected by faulting and post-depositional volcanic activity. As a result, there are variations in the properties and rank of the coal samples. The most abundant coal maceral group is huminite and the most abundant maceral is gelinite. The liptinite and inertinite contents of the coal are low and the maceral contents of the coals show great similarity. The depositional environments of the all coals are lacustrine dominated. (author)

  4. Agriculture and brown coal surface mining. The example of the Rhenish brown coal mining area

    International Nuclear Information System (INIS)

    Heck, B.

    1994-01-01

    Extensive surface mining in the Rhenish brown coal exploitation area has led to marked changes to the environment and living conditions there. This applies particularly to agriculture, which now has to subsist with a competitor for land. The progressive sacrifice of farmland and widespread relocation compaigns are grossly interfering with the business of farming. Only in exceptional cases do farms move as part of the relocation of whole villages. New sites are often found in hamlets and group settlements. This happens in connection with farming of newly reclaimed land or recultivated land reorganised and returned in land consolidation campaigns. (orig.) [de

  5. Material Properties and Characteristics for Development of an Expert System for Coal-Tar Sealers

    National Research Council Canada - National Science Library

    Shoenberger, James

    2001-01-01

    .... Several coal-tar mixtures that varied with source of the coal-tar emulsion, amount of aggregate, and amount of polymer used in the mixtures were evaluated for their field performance and material properties...

  6. Evaluation of the coal properties of Norte de Santander

    International Nuclear Information System (INIS)

    1987-07-01

    The Project Characterization of Coal of Norte de Santander, concluded in the second semester of 1986 with the presentation of the 4 final reports of the participant entities: Universidad Nacional de Colombia - Bogota, Universidad Francisco de Paula Santander, Instituto de Investigaciones Technologicas (I.I.T.), and Instituto de Investigaciones geologico Mineras - INGEOMINAS. In each Institution some common aspects were worked - analytic part and other specific topics, that which believes the necessity to develop a study that unified the parts worked jointly with the elaboration of a new chart of data, and it allowed this way to assemble the analytic base with the studies of some technological properties and of benefit. Initially it is made a summary of the most excellent aspects in the Geology, mining and Commercialization of the Coal of the department and later on with reference to all the available analytic information, new data were obtained with base in averages among Institutions, checkups of differing results, correlate and discard of rusty samples. For the chemical and physicochemical analyses, the plastic properties, the petrographic results, the chemical analysis of the ashes, they were made statistical and correlative new treatment discriminating against the different sectors and formations inside the area (the Formation Catatumbo was excepted). For the analyses more used as range indicators and others of quality were carried out three-dimensional graphic that summarize in a visual form the variation of the parameter through the study area and the sectors inside this being obtained the iso-values curves equally. The study of some properties of the coal related with technological processes like coking, liquefaction and of benefit they supplement the analytic characterization being able to obtain several practical conclusions as for the use of these coal and remarking some concrete problems to solve with the objective of improving the quality of the

  7. Uncertainty in coal property valuation in West Virginia: A case study

    Science.gov (United States)

    Hohn, M.E.; McDowell, R.R.

    2001-01-01

    Interpolated grids of coal bed thickness are being considered for use in a proposed method for taxation of coal in the state of West Virginia (United States). To assess the origin and magnitude of possible inaccuracies in calculated coal tonnage, we used conditional simulation to generate equiprobable realizations of net coal thickness for two coals on a 7 1/2 min topographic quadrangle, and a third coal in a second quadrangle. Coals differed in average thickness and proportion of original coal that had been removed by erosion; all three coals crop out in the study area. Coal tonnage was calculated for each realization and for each interpolated grid for actual and artificial property parcels, and differences were summarized as graphs of percent difference between tonnage calculated from the grid and average tonnage from simulations. Coal in individual parcels was considered minable for valuation purposes if average thickness in each parcel exceeded 30 inches. Results of this study show that over 75% of the parcels are classified correctly as minable or unminable based on interpolation grids of coal bed thickness. Although between 80 and 90% of the tonnages differ by less than 20% between interpolated values and simulated values, a nonlinear conditional bias might exist in estimation of coal tonnage from interpolated thickness, such that tonnage is underestimated where coal is thin, and overestimated where coal is thick. The largest percent differences occur for parcels that are small in area, although because of the small quantities of coal in question, bias is small on an absolute scale for these parcels. For a given parcel size, maximum apparent overestimation of coal tonnage occurs in parcels with an average coal bed thickness near the minable cutoff of 30 in. Conditional bias in tonnage for parcels having a coal thickness exceeding the cutoff by 10 in. or more is constant for two of the three coals studied, and increases slightly with average thickness for the

  8. Morphological and Strength Properties of Tanjung Bin Coal Ash Mixtures for Applied in Geotechnical Engineering Work

    OpenAIRE

    Awang, Abd. Rahim; Marto, Aminaton; Makhtar, Ahmad Maher

    2012-01-01

    In Malaysia, coal has been used as a raw material to generate electricity since 1988. In the past, most of the wastage of coal burning especially the bottom ash was not managed properly as it was dumped in the waste pond and accumulated drastically.This paper focuses on some properties of coal ash mixtures (fly  ash and bottom ash mixtures) from Tanjung Bin power plant. The characteristics studied were morphological properties, compaction behaviour and strength properties. Strength properties...

  9. Thermal surface characteristics of coal fires 1 results of in-situ measurements

    Science.gov (United States)

    Zhang, Jianzhong; Kuenzer, Claudia

    2007-12-01

    Natural underground coal fires are fires in coal seams occurring subsurface. The fires are ignited through a process named spontaneous combustion, which occurs based on a natural reaction but is usually triggered through human interaction. Coal mining activities expose coal to the air. This leads to the exothermal oxidation of the carbon in the coal with the air's oxygen to CO 2 and - under certain circumstances - to spontaneous combustion. Coal fires occur in many countries world wide - however, currently the Chinese coal mining industry faces the biggest problems with coal fires. Coal fires destroy the valuable resource coal and furthermore lead to many environmental degradation phenomena such as the deterioration of surrounding vegetation, land subsidence and the emission of toxic gasses (CO, N 2O). They additionally contribute to the emission of green house relevant gasses such as CO 2 and CH 4 to the atmosphere. In this paper we present thermal characteristics of coal fires as measured in-situ during a field campaign to the Wuda coal fire area in south-central Inner Mongolia, China. Thermal characteristics include temperature anomaly measurements at the surface, spatial surface temperature profiles of fire areas and unaffected background areas, diurnal temperature profiles, and temperature measurements inside of coal fire induced cracks in the overlying bedrock. For all the measurements the effects of uneven solar heating through influences of slope and aspect are considered. Our findings show that coal fires result in strong or subtle thermal surface anomalies. Especially the latter can easily be influenced by heating of the surrounding background material through solar influences. Temperature variation of background rocks with different albedo, slope, aspect or vegetation cover can substantially influence the detectability of thermal anomalies. In the worst case coal fire related thermal anomalies can be completely masked by solar patterns during the daytime

  10. 30 CFR 942.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal mining by act of Congress. 942.761 Section 942.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining...

  11. 30 CFR 903.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal mining by act of Congress. 903.761 Section 903.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... Congress. Part 761 of this chapter, Areas Designated by Act of Congress, applies to surface coal mining...

  12. 30 CFR 910.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal mining by Act of Congress. 910.761 Section 910.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining...

  13. 30 CFR 937.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... mining by Act of Congress. 937.761 Section 937.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... WITHIN EACH STATE OREGON § 937.761 Areas designated unsuitable for surface coal mining by Act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining and...

  14. 30 CFR 921.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal mining by Act of Congress. 921.761 Section 921.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining...

  15. 30 CFR 912.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... mining by act of Congress. 912.761 Section 912.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... WITHIN EACH STATE IDAHO § 912.761 Areas designated unsuitable for surface coal mining by act of Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining and...

  16. 30 CFR 947.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal mining by act of Congress. 947.761 Section 947.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining...

  17. 30 CFR 939.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal mining by Act of Congress. 939.761 Section 939.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining...

  18. 30 CFR 941.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal mining by act of Congress. 941.761 Section 941.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining...

  19. 30 CFR 922.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal mining by act of Congress. 922.761 Section 922.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining...

  20. 30 CFR 905.761 - Areas designated unsuitable for surface coal mining by act of Congress.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal mining by act of Congress. 905.761 Section 905.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... Congress. Part 761 of this chapter, Areas Designated by Act of Congress, shall apply to surface coal mining...

  1. An intelligent hybrid system for surface coal mine safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Lilic, N.; Obradovic, I.; Cvjetic, A. [University of Belgrade, Belgrade (Serbia)

    2010-06-15

    Analysis of safety in surface coal mines represents a very complex process. Published studies on mine safety analysis are usually based on research related to accidents statistics and hazard identification with risk assessment within the mining industry. Discussion in this paper is focused on the application of AI methods in the analysis of safety in mining environment. Complexity of the subject matter requires a high level of expert knowledge and great experience. The solution was found in the creation of a hybrid system PROTECTOR, whose knowledge base represents a formalization of the expert knowledge in the mine safety field. The main goal of the system is the estimation of mining environment as one of the significant components of general safety state in a mine. This global goal is subdivided into a hierarchical structure of subgoals where each subgoal can be viewed as the estimation of a set of parameters (gas, dust, climate, noise, vibration, illumination, geotechnical hazard) which determine the general mine safety state and category of hazard in mining environment. Both the hybrid nature of the system and the possibilities it offers are illustrated through a case study using field data related to an existing Serbian surface coal mine.

  2. Coal

    International Nuclear Information System (INIS)

    Teissie, J.; Bourgogne, D. de; Bautin, F.

    2001-12-01

    Coal world production represents 3.5 billions of tons, plus 900 millions of tons of lignite. 50% of coal is used for power generation, 16% by steel making industry, 5% by cement plants, and 29% for space heating and by other industries like carbo-chemistry. Coal reserves are enormous, about 1000 billions of tons (i.e. 250 years of consumption with the present day rate) but their exploitation will be in competition with less costly and less polluting energy sources. This documents treats of all aspects of coal: origin, composition, calorific value, classification, resources, reserves, production, international trade, sectoral consumption, cost, retail price, safety aspects of coal mining, environmental impacts (solid and gaseous effluents), different technologies of coal-fired power plants and their relative efficiency, alternative solutions for the recovery of coal energy (fuel cells, liquefaction). (J.S.)

  3. Study on the combustion properties of bio-coal briquette blends of ...

    African Journals Online (AJOL)

    This study was carried out to investigate the properties of bio-coal briquette produced from blending cassava stalk and coal. The cassava stalk and coal lumps were carbonized at 160 oC, pulverized and used to produce biocoal briquettes of 10 %, 20 %, 30 %, 40 %, 50 %, 60 %,70 %, 80 %, 90 % and 100 % biomasses.

  4. Comparison of the associative structure of two different types of rich coals and their coking properties

    Energy Technology Data Exchange (ETDEWEB)

    Hengfu Shui; Changhui Lin; Meng Zhang; Zhicai Wang; Mingdong Zheng [Anhui University of Technology, Maanshan (China). School of Chemistry and Chemical Engineering

    2010-07-15

    Solvent extractions of two different types of Chinese rich coals i.e. Aiweiergou coal (AG) and Zaozhuang coal (ZZ) using the mixed solvent of carbon disulfide/N-methyl-2-pyrrolidinone (CS{sub 2}/NMP) with different mixing ratios were carried out and the caking indexes of the extracted residues were measured. It was found that the extracted residues from the two types of coals showed different changing tendencies of the caking indexes with the extraction yield. When the extraction yield attained about 50% for ZZ coal, the extracted residue had no caking property. However for AG coal, when the extraction yield reached the maximum of 63.5%, the corresponding extracted residue still had considerable caking property with the caking index of 25. This difference indicated the different associative structure of the two coals although they are of the same coalification. Hydro-thermal treatment of the two rich coals gave different extract fractionation distributions for the treated coals compared to those of raw coals respectively. The coking property evaluations of the two coals and their hydro-thermally treated ones were carried out in a crucible coking determination. The results showed that the hydro-thermal treatment could greatly improve the micro-strengths of the resulting coke from the two coals, and the improvement was more significant for the more aggregated AG coal. The reactivities of hydro-thermally treated AG coal blends were almost the same as those of raw coal blends. The higher coke reactivities of AG raw coal and its hydro-thermally treated ones than those of ZZ coal might be attributed to its special ash composition. 20 refs.,4 figs., 5 tabs.

  5. An assessment of chemical properties and hardgrove grindability index of punjab coal

    International Nuclear Information System (INIS)

    Shahzad, M.; Iqbal, M.M.; Hassan, S.A.

    2014-01-01

    This paper deals with the delamination of chemical properties and hardgrove grindability index (HGI) of coal samples collected from three different coal fields of Punjab; Eastern Salt Range, Central Salt Range and Makerwal coal fields. The chemical properties of Punjab coal reveal that most of the Punjab coal belongs to sub-bituminous category except coal of Tunnel C section of Makerwal Collieries and Iqbal Mineral coal mine of Dalwal, which are high volatile bituminous and lignite, respectively. The results of the research show that the HGI values of Punjab coal vary from 57 to 92. The eastern salt range coals are found to be the softest coals among that of three coal fields. It was further observed that the HGI values of the Punjab coal decrease with increasing moisture content, fixed carbon and sulphur contents, while it has a positive relation with volatile matter, ash content and gross calorific value. It was concluded that moisture content at its lower range has negligible effect on HGI of the Punjab coal. (author)

  6. Underground coal mine subsidence impacts on surface water

    International Nuclear Information System (INIS)

    Stump, D.E. Jr.

    1992-01-01

    This paper reports that subsidence from underground coal mining alters surface water discharge and availability. The magnitude and areal extent of these impacts are dependent on many factors, including the amount of subsidence, topography, geology, climate, surface water - ground water interactions, and fractures in the overburden. There alterations may have positive and/or negative impacts. One of the most significant surface water impacts occurred in July 1957 near West Pittston, Pennsylvania. Subsidence in the Knox Mine under the Coxton Yards of the Lehigh Valley Railroad allowed part of the discharge in the Susquehanna River to flow into the mine and create a crater 200 feet in diameter and 300 feet deep. Fourteen railroad gondola cars fell into the hole which was eventually filled with rock, sand, and gravel. Other surface water impacts from subsidence may include the loss of water to the ground water system, the gaining of water from the ground water system, the creation of flooded subsidence troughs, the increasing of impoundment storage capacity, the relocation of water sources (springs), and the alteration of surface drainage patterns

  7. Coal dust contiguity-induced changes in the concentration of TNF- and NF- B p65 on the ocular surface

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Z.Y.; Hong, J.; Liu, Z.Y.; Jin, X.D.; Gu, C.H. [China Medical University, Shenyang (China)

    2009-07-01

    To observe the influence of coal dust on ocular surface of coal miners and rabbits with coal dust contiguity on expression TNF- and NF- Bp65 and dry eye occurrence. Expression TNF- and NF- Bp65 in ocular surface were determined. Results showed tear production, BUT and lysozyme decreased for coal miners and rabbits with coal dust contiguity. Coal dust exposure was linked to development of xerophthalmia, and induced a higher expression of NF- B p65 and TNF- perhaps as a mechanism to resist coal dust ocular surface injury.

  8. Coal geopolitics

    International Nuclear Information System (INIS)

    Giraud, P.N.; Suissa, A.; Coiffard, J.; Cretin, D.

    1991-01-01

    This book divided into seven chapters, describes coal economic cycle. Chapter one: coals definition; the principle characteristics and properties (origin, calorific power, international classification...) Chapter two: the international coal cycle: coal mining, exploration, coal reserves estimation, coal handling coal industry and environmental impacts. Chapter three: the world coal reserves. Chapter four: the consumptions, productions and trade. Chapter five: the international coal market (exporting mining companies; importing companies; distributors and spot market operators) chapter six: the international coal trade chapter seven: the coal price formation. 234 refs.; 94 figs. and tabs [fr

  9. 30 CFR 933.761 - Areas designated unsuitable for surface coal mining by Act of Congress.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Areas designated unsuitable for surface coal mining by Act of Congress. 933.761 Section 933.761 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION... Congress. Part 761 of this chapter, Areas Designated Unsuitable for Coal Mining by Act of Congress, with...

  10. Surface properties of beached plastics.

    Science.gov (United States)

    Fotopoulou, Kalliopi N; Karapanagioti, Hrissi K

    2015-07-01

    Studying plastic characteristics in the marine environment is important to better understand interaction between plastics and the environment. In the present study, high-density polyethylene (HDPE), polyethylene terephalate (PET), and polyvinyl chloride (PVC) samples were collected from the coastal environment in order to study their surface properties. Surface properties such as surface functional groups, surface topography, point of zero charge, and color change are important factors that change during degradation. Eroded HDPE demonstrated an altered surface topography and color and new functional groups. Eroded PET surface was uneven, yellow, and occasionally, colonized by microbes. A decrease in Fourier transform infrared (FTIR) peaks was observed for eroded PET suggesting that degradation had occurred. For eroded PVC, its surface became more lamellar and a new FTIR peak was observed. These surface properties were obtained due to degradation and could be used to explain the interaction between plastics, microbes, and pollutants.

  11. Effect of hydrothermal treatment on some properties of Shenhua coal

    Energy Technology Data Exchange (ETDEWEB)

    Wang Zhi-cai; Shui Heng-fu; Zhang De-xiang; Gao Jin-sheng [East China University of Science and Technology, Shanghai (China). College of Resource and Environmental Engineering

    2006-10-15

    Effects of hydrothermal treatment on swelling, extraction and liquefaction behavior of Shenhua coal were studied through analyses of element content, ash content, volatile content and IR spectrum of treated coal. The results indicate that hydrogenation of coal is distinctly carried out in the process of hydrothermal pre-treatment and the hydrogen content of treated coal is more than that of raw coal. The contents of ash and volatile matters of treated coal are lower than those of raw coal. With the increase of treatment temperature the volatile content of the hydrothermal treated coal decreases and the ash content of treated coal increases. CO{sub 2} is main gas product and unvaries with the temperature changing, whereas CO and CH{sub 4} are formed when the temperature is above 250{sup o}C and increase with the temperature during hydrothermal treatment. Hydrothermal treatment is not in favor of coal swelling and the swelling ratio of treated coal decreases with the increase of treatment temperature. The swelling ratio of extraction residue by CS{sub 2}/NMP mixed solvent in NMP solvent is lower than that of the corresponding raw coal. The CS{sub 2}/NMP mixed solvent extraction yields of coal treated at appropriate temperature are higher than that of raw coal, but the extraction yields of treated coal obtained by n-hexane, toluene and THF successive Soxhelt extraction are lower. Hydrothermal treatment at 250-300{sup o}C can increase the conversion of treated coal in direct hydro-liquefaction. The gas + oil yield of treated coal is lower than that of raw coal and the preasphaltene yield of treated coal is much higher. IR spectra of treated coals show that the forms of non-covalent bonds are changed by hydrothermal treatment, and the hydrolysis of ester and ether bonds and the pyrolysis of aromatic side chains also maybe occur at high treatment temperature. 21 refs., 3 figs., 4 tabs.

  12. Effect of pre-swelling of coal on its solvent extraction and liquefaction properties

    Energy Technology Data Exchange (ETDEWEB)

    Hengfu Shui; Zhicai Wang; Meixia Cao [Anhui University of Technology, Ma' anshan (China). School of Chemistry and Chemical Engineering

    2008-10-15

    Effects of pre-swelling of coal on solvent extraction and liquefaction properties were studied with Shenhua coal. It was found that pre-swelling treatments of the coal in three solvents, i.e., toluene (TOL), N-methyl-2-pyrrolidinone (NMP) and tetralin (THN) increased its extraction yield and liquefaction conversion, and differed the liquefied product distributions. The pre-swollen coals after removing the swelling solvents showed increased conversion in liquefaction compared with that of the swollen coals in the presence of swelling solvents. It was also found that the yields of (oil + gas) in liquefaction of the pre-swollen coals with NMP and TOL dramatically decreased in the presence of swelling solvent. TG and FTIR analyses of the raw coal, the swollen coals and the liquefied products were carried out in order to investigate the mechanism governing the effects of pre-swelling treatment on coal extraction and liquefaction. The results showed that the swelling pre-treatment could disrupt some non-covalent interactions of the coal molecules, relax its network structure and loosened the coal structure. It would thus benefit diffusion of a hydrogen donor solvent into the coal structure during liquefaction, and also enhance the hydrogen donating ability of the hydrogen-rich species derived from the coal. 21 refs., 4 figs., 3 tabs.

  13. Study of the mechanical properties of brown coal

    Energy Technology Data Exchange (ETDEWEB)

    Okruszek, Z

    1980-01-01

    The techniques and the results of studies of the mechanical properties of brown coal discovered in a zone adjacent to the location of the Rogowiec power plant (Poland) are described. The studies were conducted by the geotechnical laboratory of the Polytechnical Institute in the city of Lodz. Included in the program of studies were: tests of the brown coal (eight samples with a diameter to height ratio of d/h = 10.0/7.5; 11.1/7.8; 9.3/8.8; 8.1/6.8; 8.5/9.4; 8.0/8.8; 7.9/7.6 adn 8.8/8.6; dimensions in centimeters) for single axis compression (destroying stress was found to be 0.778; 0.660; 0.376; 0.804; 0.140; 0.472; 0.408 and 0.278 MPa); tests of samples (five units) for shear strength (the chip force is 0.36; 0.46; 0.39; 0.11 and 0.36 kilonewtons); tests of the samples (two samples, both with a diameter of 3.8 cm and a height of 7.6 cm) for stretching (the destructive force is 50.1 and 54.9 kilonewtons); odometric tests to determine the odometric modulus of compressibility of the brown coal (a total of four samples; three of which were loaded by a force in the range of 0.6-1.2 MPa and one in the range of 0-1.1 MPa; the odometric modulus of compressibility is in the range of 45.1 to 116.7 depending on the loading conditions) and tests for triple axial compression (two samples, both with a diameter of 3.8 cm and a height of 7.6 cm; the destroying pressure was found to be equal to 0.5 and 0.27 MPa).

  14. Effects of coal storage in air on physical and chemical properties of coal and on gas adsorption

    Science.gov (United States)

    Mastalerz, Maria; Solano-Acosta, W.; Schimmelmann, A.; Drobniak, A.

    2009-01-01

    This paper investigates changes in the high-volatile bituminous Lower Block Coal Member from Indiana owing to moisture availability and oxidation in air at ambient pressure and temperature over storage time. Specifically, it investigates changes in chemistry, in surface area, and pore structure, as well as changes in methane and carbon dioxide adsorption capacities. Our results document that the methane adsorption capacity increased by 40%, whereas CO2 adsorption capacity increased by 18% during a 13-month time period. These changes in adsorption are accompanied by changes in chemistry and surface area of the coal. The observed changes in adsorption capacity indicate that special care must be taken when collecting samples and preserving coals until adsorption characteristics are measured in the laboratory. High-pressure isotherms from partially dried coal samples would likely cause overestimation of gas adsorption capacities, lead to a miscalculation of coal-bed methane prospects, and provide deceptively optimistic prognoses for recovery of coal-bed methane or capture of anthropogenic CO2. ?? 2009 Elsevier B.V. All rights reserved.

  15. Study on the Combustion Properties of Bio-Coal Briquette Blends of ...

    African Journals Online (AJOL)

    2017-10-09

    Oct 9, 2017 ... This study was carried out to investigate the properties of bio-coal briquette produced from blending cassava stalk and coal. ... solar, gas and kerosene will certainly take a few decades to ..... Physical Properties of. Briquettes ...

  16. Relationship between coal and coke microstructure and the high temperature properties of coke. [Temperature dependence

    Energy Technology Data Exchange (ETDEWEB)

    Tsuyuguchi, K; Yamaji, M; Sugimoto, Y

    1980-02-01

    This paper considers the relationship of the properties of coke and parent coal with the high temperature properties, including reactivity, of coke. Aspects considered include coke texture and grade, and the optical reflectivity of coal and coke. (8 refs.) (In Japanese)

  17. Modeling forest ecosystem changes resulting from surface coal mining in West Virginia

    Science.gov (United States)

    John Brown; Andrew J. Lister; Mary Ann Fajvan; Bonnie Ruefenacht; Christine Mazzarella

    2012-01-01

    The objective of this project is to assess the effects of surface coal mining on forest ecosystem disturbance and restoration in the Coal River Subbasin in southern West Virginia. Our approach is to develop disturbance impact models for this subbasin that will serve as a case study for testing the feasibility of integrating currently available GIS data layers, remote...

  18. Fuel production from microwave assisted pyrolysis of coal with carbon surfaces

    International Nuclear Information System (INIS)

    Mushtaq, Faisal; Mat, Ramli; Ani, Farid Nasir

    2016-01-01

    Highlights: • MW heating of coal was carried out with uniformly distributed carbon surfaces. • The effects of carbon loading, MW power and N 2 flow rate were investigated. • Heating profile, pyrolysis products are influenced by the process variables. • Highest coal-tar obtained when final temperature sustained for longer duration. • Coal-tar is mainly composed of aromatics and saturated aliphatics hydrocarbons. - Abstract: In this study, coal solids were subjected to Microwave (MW) pyrolysis conditions. Coconut Activated Carbon (CAC) solids used as a MW absorber was distributed uniformly over coal solids to reduce hotspots. Three process parameters; CAC loading, MW power and N 2 flow rate were studies on pyrolysis heating performance. The highest coal-tar yield of 18.59 wt% was obtained with 600 W, 75 wt% CAC loading and 4 Liter per Minute (LPM) of N 2 flow rate. This improved coal-tar yield is mainly of the fact that higher MW power and CAC loading produced sustained pyrolysis conditions for longer duration for the complete conversion of pyrolysis solids. The coal-tar was composed mainly of aromatics (naphthalenes, benzenes and xylene) and saturated aliphatics (alkanes and alkenes) hydrocarbons. The gas produced from pyrolysis of coal is mainly of H 2 40.23–65.22 vol%.

  19. The mechanical properties and hydration characteristics of cement pastes containing added-calcium coal gangue

    Energy Technology Data Exchange (ETDEWEB)

    Dongxu Li; Xuyan Song [Nanjing University of Technology, Nanjing (China). College of Material Science and Engineering

    2008-04-15

    The mechanical properties of several kinds of coal gangue calcined with limestone were researched so as to find the optimum way of calcinations with limestone. The microstructure and property of hydration process of cement pastes containing added-calcium coal gangue were analyzed by means of scanning electron microscope (SEM) and the method of mercury in trusion poremeasurement. When the proper amounst of gypsum and fluorite were taken as mineralizers in the course of calcinations of added-calcium coal gangue, the activity of coal gangue can be effectively improved. The results of mechanical property and structural characteristics such as hydration, hydration products and microstructure etc. of cement pastes containing added-calcium coal gangue are consistent.

  20. Prime farmland disturbance from coal surface mining in the corn belt, 1980-2000

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, D.P.

    1979-09-01

    The five midwestern states that make up the Corn Belt farm production region - Illinois, Indiana, Iowa, Missouri, and Ohio - contain about 110 billion tons of coal reserves (19% of which are surface mineable) and 110 million acres of arable land (69% of which are prime farmlands). In 1975, this region was the site of 21% of the nation's total coal production and 50% of the nation's corn and soybean harvest. Because corn and soybeans are key elements in US foreign trade and because nearly two-thirds of the regional coal production is from surface coal mines, it is important to understand the potential conflicts that may arise between the coal and agricultural industries in the Corn Belt. This report presents background data on the coal and agricultural industries in the Corn Belt states, along with the results of a quantitative analysis of the potential disruption of land and associated prime farmland due to future coal surface mining activity in the region. Estimates of potential land dusruptions indicate that 452,000 acres of land, including 127,000 acres of prime farmland, could be disturbed in the period 1980-2000. Additionally, the data indicate that certain counties in the Corn Belt states may experience impacts significantly greater than the regional average would suggest.

  1. Experimental investigation on variation of physical properties of coal samples subjected to microwave irradiation

    Science.gov (United States)

    Hu, Guozhong; Yang, Nan; Xu, Guang; Xu, Jialin

    2018-03-01

    The gas drainage rate of low-permeability coal seam is generally less than satisfactory. This leads to the gas disaster of coal mine, and largely restricts the extraction of coalbed methane (CBM), and increases the emission of greenhouse gases in the mining area. Consequently, enhancing the gas drainage rate is an urgent challenge. To solve this problem, a new approach of using microwave irradiation (MWR) as a non-contact physical field excitation method to enhance gas drainage has been attempted. In order to evaluate the feasibility of this method, the methane adsorption, diffusion and penetrability of coal subjected to MWR were experimentally investigated. The variation of methane adsorbed amount, methane diffusion speed and absorption loop for the coal sample before and after MWR were obtained. The findings show that the MWR can change the adsorption property and reduce the methane adsorption capacity of coal. Moreover, the methane diffusion characteristic curves for both the irradiated coal samples and theoriginal coal samples present the same trend. The irradiated coal samples have better methane diffusion ability than the original ones. As the adsorbed methane decreases, the methane diffusion speed increases or remain the same for the sample subjected to MWR. Furthermore, compared to the original coal samples, the area of the absorption loop for irradiated samples increases, especially for the micro-pore and medium-pore stage. This leads to the increase of open pores in the coal, thus improving the gas penetrability of coal. This study provides supports for positive MWR effects on changing the methane adsorption and improving the methane diffusion and the gas penetrability properties of coal samples.

  2. Coal tar pitch. Interrelations between properties and utilization of coal tar pitch

    Energy Technology Data Exchange (ETDEWEB)

    Collin, G; Koehler, H [Ruetgerswerke A.G., Duisburg (Germany, F.R.)

    1977-06-01

    Coal tar pitch is won as a highly aromatic, thermoplastic residue by destillating coal tar. In this paper the structure as well as the chemical and physical data of this pitch are introduced. In addition to this the actual as well as possible applications are indicated. For example, the pitch can be used for the production of binders, e.g. for electrodes and road construction as well as in combination with plastics for the production of insulating material and corrosion protection material.

  3. Phase transformations in synthesis technologies and sorption properties of zeolites from coal fly ash

    Directory of Open Access Journals (Sweden)

    О. Б. Котова

    2016-08-01

    Full Text Available Coal fly ash is generated in the course of combustion of coal at thermal power plants. Environmental problems increase sharply without disposing that industrial waste. Technologies were tested of hydrothermal synthesis of zeolites from fly ash forming during combustion of coal at thermal power plants of the Pechora coal basin and dependences were identified of the experiment conditions on physical and chemical properties of the end product. It is demonstrated that synthesizing zeolites from fly ash is the first stage of forming ceramic materials (ceramic membranes, which defines the fundamental character (importance of that area of studies. It was for the first time that sorption and structural characteristics and cation-exchange properties of fly ash from the Pechora basin coals were studied with respect to, Ba2+ and Sr2+.

  4. Environmental impact of coal mining and coal seam gas production on surface water quality in the Sydney basin, Australia.

    Science.gov (United States)

    Ali, A; Strezov, V; Davies, P; Wright, I

    2017-08-01

    The extraction of coal and coal seam gas (CSG) will generate produced water that, if not adequately treated, will pollute surface and groundwater systems. In Australia, the discharge of produced water from coal mining and related activities is regulated by the state environment agency through a pollution licence. This licence sets the discharge limits for a range of analytes to protect the environment into which the produced water is discharged. This study reports on the impact of produced water from coal mine activities located within or discharging into high conservation environments, such as National Parks, in the outer region of Sydney, Australia. The water samples upstream and downstream from the discharge points from six mines were taken, and 110 parameters were tested. The results were assessed against a water quality index (WQI) which accounts for pH, turbidity, dissolved oxygen, biochemical oxygen demand, total dissolved solids, total phosphorus, nitrate nitrogen and E .coli. The water quality assessment based on the trace metal contents against various national maximum admissible concentration (MAC) and their corresponding environmental impacts was also included in the study which also established a base value of water quality for further study. The study revealed that impacted water downstream of the mine discharge points contained higher metal content than the upstream reference locations. In many cases, the downstream water was above the Australia and New Zealand Environment Conservation Council and international water quality guidelines for freshwater stream. The major outliers to the guidelines were aluminium (Al), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn). The WQI of surface water at and downstream of the discharge point was lower when compared to upstream or reference conditions in the majority of cases. Toxicology indices of metals present in industrial discharges were used as an additional tool to assess water quality, and the newly

  5. Properties of Direct Coal Liquefaction Residue Modified Asphalt Mixture

    Directory of Open Access Journals (Sweden)

    Jie Ji

    2017-01-01

    Full Text Available The objectives of this paper are to use Direct Coal Liquefaction Residue (DLCR to modify the asphalt binders and mixtures and to evaluate the performance of modified asphalt mixtures. The dynamic modulus and phase angle of DCLR and DCLR-composite modified asphalt mixture were analyzed, and the viscoelastic properties of these modified asphalt mixtures were compared to the base asphalt binder SK-90 and Styrene-Butadiene-Styrene (SBS modified asphalt mixtures. The master curves of the asphalt mixtures were shown, and dynamic and viscoelastic behaviors of asphalt mixtures were described using the Christensen-Anderson-Marasteanu (CAM model. The test results show that the dynamic moduli of DCLR and DCLR-composite asphalt mixtures are higher than those of the SK-90 and SBS modified asphalt mixtures. Based on the viscoelastic parameters of CAM models of the asphalt mixtures, the high- and low-temperature performance of DLCR and DCLR-composite modified asphalt mixtures are obviously better than the SK-90 and SBS modified asphalt mixtures. In addition, the DCLR and DCLR-composite modified asphalt mixtures are more insensitive to the frequency compared to SK-90 and SBS modified asphalt mixtures.

  6. Electric-surface characteristics and stability of type K coal suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Baichenko, A A; Baran, A A; Mitina, N S; Kocherga, I I

    1987-07-01

    Investigates with the help of potentiometric titration, electrophoresis and conductometry the structure of double electric layer and aggregation stability of type K coal suspension at the Berezovsk preparation plant (Kuzbassugol' association). Discusses tests carried out with coal which was preliminarily crushed, sieved, crushed again in colloid mills, elutriated and separated into sedimento-stable fractions. Data obtained indicate that coal suspensions represent typical ion-stabilized dispersions, coagulation of which by electrolytes can be depicted within the framework of lyophobic colloid stability theory. Addition of double-charged gegenions considerably reduces electrokinetic potential while addition of triple-charged gegenions results in surface recharging. 10 refs.

  7. Case study on ground surface deformation induced by CO2 injection into coal seam

    International Nuclear Information System (INIS)

    Li Hong; Tang Chun'an

    2010-01-01

    To monitor a geomechanical response of injecting CO 2 into relatively shallow coal seams, tiltmeters were set as an array to cover the ground surface area surrounding the injection well, and to measure the ground deformation during a well fracturing stimulation and a short-term CO 2 injection test. In this paper, an attempt to establish a quantitative relationship between the in-situ coal swelling and the corresponding ground deformation was made by means of numerical simulation study. (authors)

  8. Influence of coal properties on mercury uptake from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, J.; Brown, S.D.; Snape, C.E. [Miskolc University, Miskolc-Egyetemvaros (Hungary). Research Inst. of Applied Chemistry

    1999-10-01

    The uptake of mercury (II) from aqueous solution by a range of coals has been studied and the results have been compared to those for a number of other sorbents, including commercial active carbons and cation-exchange resins. At pH 5 in a buffer medium, the capacities for mercury removal of the low-rank coals and the oxidized bituminous coals investigated are comparable to those of the other sorbents tested. For the lignites investigated, a high content of organic sulfur does not markedly affect the capacity for mercury uptake in relatively neutral and low chloride media, owing to redox reactions being the most likely mechanism involved. However, in highly acidic solutions, the capacities for mercury uptake are considerably greater for the high-sulfur coals investigated than for their low-sulfur counterparts due to chelation being the major sorption process involved. 36 refs., 4 figs., 7 tabs.

  9. Textural properties in density-separated coal fractions

    Energy Technology Data Exchange (ETDEWEB)

    Rubiera, F.; Parra, J.B.; Arenillas, A.; Hall, S.T.; Shah, C.L.; Pis, J.J. [CSIC, Oviedo (Spain). Inst. Nacional del Carbon

    1999-11-01

    The results presented in this work are part of a more extensive research programme aimed at assessing the impact of coal porous structure on density-based process evaluation and modelling. The coal samples used were obtained from two different density-based cleaning processes, a Vorsyl dense medium separator for treating an anthracite (TW) with a size fraction of 0.5-8.0 mm and a spiral concentrator for treating a bituminous coal (DH) with a size of less than 2 mm. Textural characterisation of the samples was carried out by measuring true (helium) and apparent (mercury) densities and mercury porosimetry up to a maximum pressure of 200 MPa. Adsorption isotherms in CO{sub 2} at 273 K were also determined for both coal series. In the case of the bituminous coal series a linear relationship between porosity and ash level was found. This may have important implications if coal porosity and/or textural parameters need to be incorporated into new density-based simulation models. 24 refs., 6 figs., 5 tabs.

  10. Magneto-transport properties of oriented Mn{sub 2}CoAl films sputtered on thermally oxidized Si substrates

    Energy Technology Data Exchange (ETDEWEB)

    Xu, G. Z.; Du, Y.; Zhang, X. M.; Liu, E. K.; Wang, W. H., E-mail: wenhong.wang@iphy.ac.cn; Wu, G. H. [State Key Laboratory for Magnetism, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China); Zhang, H. G. [College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124 (China)

    2014-06-16

    Spin gapless semiconductors are interesting family of materials by embracing both magnetism and semiconducting due to their unique band structure. Its potential application in future spintronics requires realization in thin film form. In this Letter, we report fabrication and transport properties of spin gapless Mn{sub 2}CoAl films prepared on thermally oxidized Si substrates by magnetron sputtering deposition. The films deposited at 673 K are well oriented to (001) direction and display a uniform-crystalline surface. Magnetotransport measurements on the oriented films reveal a semiconducting-like resistivity, small anomalous Hall conductivity, and linear magnetoresistance representative of the transport signatures of spin gapless semiconductors. The magnetic properties of the films have also been investigated and compared to that of bulk Mn{sub 2}CoAl, showing small discrepancy induced by the composition deviation.

  11. 30 CFR 942.800 - Bond and insurance requirements for surface coal mining and reclamation operations.

    Science.gov (United States)

    2010-07-01

    ... required for postmining water treatment must remain bonded. However, the trust fund or annuity may serve as... coal mining and reclamation operations. 942.800 Section 942.800 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR PROGRAMS FOR THE CONDUCT OF SURFACE MINING...

  12. Surface tension of a coal extract in an organic solvent; Sekitan chushutsu seibun no kaigo to hyomen choryoku

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, T.; Hayasaka, K.; Takanohashi, T.; Iino, M. [Tohoku University, Sendai (Japan). Institute for Chemical Reaction Science

    1996-10-28

    The behavior and properties of associated bodies were studied through measurement of surface tension considering acetone-soluble fraction relatively light among various solvent extracts of coal. In experiment, the acetone-soluble fraction was extracted from the substances extracted from Upper Freeport coal as standard specimen using the mixed solvent of carbon disulfide (CS2) and N-methyl-2-pyrrolidinone (NMP), and it was dissolved into NMP after drying. Surface tension was measured by Wilhelmy method. The experimental results are as follows. Equilibrium surface tension is equal to the surface tension of pure solvent in a low concentration range of solution, and decreases with an increase in concentration approaching a fixed value at 0 in log concentration, nearly showing an S curve. Adsorption of species with non-polar aromatic ring of the acetone-soluble fraction on a solution surface probably decreases surface tension. Change with time in surface tension is observed which suggests fast initial reaction and slow subsequent reaction. 4 figs.

  13. Effect of pre-swelling of coal on its liquefaction properties

    Energy Technology Data Exchange (ETDEWEB)

    Hengfu Shui; Zhicai Wang; Meixia Cao [Anhui University of Technology, Ma' anshan (China). School of Chemistry & Chemical Engineering

    2007-07-01

    The effects of pre-swelling of Shenhua coal on its liquefaction property were studied in this paper. It was found that pre-swelling treatments of Shenhua coal in three solvents, i.e toluene (TOL), N-methyl-2-pyrrolidinone (NMP) and tetralin (THN) increased its liquefaction conversion, and the liquefied product distributions were also quite different. Removal of the pre-swelling solvent from the swollen coals further increased the liquefaction conversion compared to that of the swollen coals with the swelling solvent existed in them. It was found that oil and gas yields for the liquefaction of swollen coals in NMP and TOL with swelling solvent existed dramatically decreased. Pre-swelling in THN at 120{sup o}C gave the highest liquefaction conversion, however the liquefaction conversion decreased with the increase of pre-swelling temperature in the case of NMP. TG and FTIR analyses of raw coal, the swollen coals and liquefied products were carried out and the mechanism of the effects of pre-swelling of coal on its extraction and liquefaction behaviors were probed in the paper. 12 refs., 6 figs., 3 tabs.

  14. Acidic surface functional groups and mineral elements in Lakra coal (Sindh, Pakistan)

    International Nuclear Information System (INIS)

    Saeed, K.; Ishaq, M.; Ahjmad, I.; Shakirullah, M.; Haider, S.

    2010-01-01

    Surface acidity of virgin coal (Lakra Sindh, Pakistan) and variously extracted/leached coal samples with HNO/sub 3/ NaOH, and KMnO/sub 4/, were investigated by aqueous potentiometric titration employing KOH as a titrant. The titration curve of virgin coal showed that its surface might contain carboxylic, carbonyl, phenolic and other weak acidic functional groups such as enols and C-H bond. The titration curves of leached coal samples showed inflections at pH 4-11, being not similar the inflections of carboxylic groups. This inflection might be given by functional groups like CO/sub 2/, phenolic, enols and C-H. Mineral matter such as Fe, K, Zn, Mn and Ni were determined in the ash of coal by atomic absorption spectrophotometer and was found that Fe (3104 micro g/g) in the highest and Ni (36.05 micro g/g) in the lowest quantity is present in virgin coal sample. (author)

  15. Bio-coal, torrefied lignocellulosic resources – Key properties for its use in co-firing with fossil coal – Their status

    International Nuclear Information System (INIS)

    Agar, D.; Wihersaari, M.

    2012-01-01

    Bio-coal has received generous amounts of media attention because it potentially allows greater biomass co-firing rates and net CO 2 emission reductions in pulverised-coal power plants. However, little scientific research has been published on the feasibility of full-scale commercial production of bio-coal. Despite this, several companies and research organisations worldwide have been developing patented bio-coal technologies. Are the expectations of bio-coal realistic and are they based on accepted scientific data? This paper examines strictly peer-reviewed scientific publications in order to find an answer. The findings to date on three key properties of torrefied biomass are presented and reviewed. These properties are: the mass and energy balance of torrefaction, the friability of the product and the equilibrium moisture content of torrefied biomass. It is these properties that will have a major influence on the feasibility of bio-coal production regardless of reactor technology employed in production. The presented results will be of use in modelling commercial production of bio-coal in terms of economics and green-house gas emission balance. -- Highlights: ► A technical note on torrefaction research results. ► Presents experimental values on three key properties. ► Mass-energy balance, grindability, equilibrium moisture content of torrefied biomass. ► Results useful for modelling bio-coal production schemes.

  16. Determining the radiative properties of pulverized-coal particles from experiments. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Menguec, M.P.

    1992-02-01

    A comprehensive coupled experimental-theoretical study has been performed to determine the effective radiative properties of pulverized-coal/char particles. The results obtained show that the ``effective`` scattering phase function of coal particles are highly forward scattering and show less sensitivity to the size than predicted from the Lorenz-Mie theory. The main reason for this is the presence of smaller size particles associated with each larger particle. Also, the coal/char particle clouds display more side scattering than predicted for the same size range spheres, indicating the irregular shape of the particles and fragmentation. In addition to these, it was observed that in the visible wavelength range the coal absorption is not gray, and slightly vary with the wavelength. These two experimental approaches followed in this study are unique in a sense that the physics of the problem are not approximated. The properties determined include all uncertainties related to the particle shape, size distribution, inhomogeneity and spectral complex index of refraction data. In order to obtain radiative property data over a wider wavelength spectrum, additional ex-situ experiments have been carried out using a Fourier Transform Infrared (FT-IR) Spectrometer. The spectral measurements were performed over the wavelength range of 2 to 22 {mu}m. These results were interpreted to obtain the ``effective`` efficiency factors of coal particles and the corresponding refractive index values. The results clearly show that the coal/char radiative properties display significant wavelength dependency in the infrared spectrum.

  17. Detecting voids in coal seams in surface mining by means of a biophysical method

    Energy Technology Data Exchange (ETDEWEB)

    Bek, E.

    1985-07-01

    Soviet research institutes, in cooperation with research intitutes from other countries, developed the Radar 1 system for detecting abandoned workings in coal seams in surface mines. The system will be used for detecting voids in seams at depths to 50 m. The Academy of Sciences of Czechoslovakia tested use of dowsing for detecting abandoned workings in the Pohranicni straz, the Brezova and the Medard coal surface mines. The workings were situated at depths from 2 to 12 m from the ground surface (dowser position). The dowser was not informed of position or dimensions of the workings. Accuracy of determining position of abandoned workings in coal seams was high. Results of dowsing were checked by drilling. 4 references.

  18. Residence time of contaminants released in surface coal mines -- a wind-tunnel study

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, R.S. [Environmental Protection Agency, Research Triangle Park, NC (United States)

    1994-12-31

    Surface coal mining operations (blasting, shoveling, loading, trucking, etc.) are sources of airborne particles. The 1990 Clean Air Act Amendments direct the EPA to analyze the accuracy of the Industrial Source Complex model and the AP-42 emission factors, and to make revisions as may be necessary to eliminate any significant over-prediction of air concentration of fugitive particles from surface coal mines. A wind-tunnel study was performed at the US EPA`s Fluid Modeling Facility to investigate dispersion from surface coal mines in support of the dispersion modeling activities. Described here is the portion of the study directed at determining the residence time that material released near the floor of a mine will stay within the mine.

  19. Binderless briquetting of some selected South African prime coking, blend coking and weathered bituminous coals and the effect of coal properties on binderless briquetting

    Energy Technology Data Exchange (ETDEWEB)

    Mangena, S.J. [Division of Mining Technology, CSIR, PO Box 395, Pretoria, 0001 (South Africa); du Cann, V.M. [Coal and Mineral Technologies (Pty) Ltd, SABS, PO Box 73656, Lynnwood Ridge, Pretoria, 0040 (South Africa)

    2007-07-02

    The binderless briquetting of some selected South African prime coking and blend coking coals, as well as the effects of weathering on the binderless briquetting of some inertinite-rich bituminous coals, were investigated in the laboratory. Selected properties of these coals were determined and the coals were briquetted at various moisture contents and pressures. Based on the results obtained in this study, binderless briquetting was found to be most successful in the cases of the fresh, vitrinite-rich coking and blend coking coals and satisfactory in the fresh inertinite-rich Witbank coals. However, the bonding process seemed to be adversely affected by weathering. The negative impact on bonding could be ameliorated to some extent by the presence of a significant kaolinite content when the percentage ash reports in the order of more than 15% (air-dry basis). It should, however, be noted that kaolinite may reduce the water resistance of the briquettes. (author)

  20. Enhancing the Properties of Coal Briquette Using Spear Grass (Imperata Cylindrica

    Directory of Open Access Journals (Sweden)

    Adaora Stellamaris OGBUAGU

    2010-12-01

    Full Text Available Studies have been carried out on utilizing agricultural wastes (spear grass to enhance the properties of coal briquette. The proximate analysis of the plant material was carried out alongside with a sample of coal (sub-bituminous coal. Briquettes of different compositions were produced by blending the plant material with the coal at various concentrations: 0%, 10%, 20%, 30%, 40%, 50% and 100%, using cassava starch as a binder and calcium hydroxide (Ca(OH2 as desulfurizing agent. The properties of the briquettes were compared. It was found that the ignition, burning rate and reduction in smoke emission showed improvement with increase in biomass concentration. Compressive strength and cooking efficiency (water boiling time and specific fuel consumption showed initial improvement and rendered to decrease with briquette containing 30% biomass.

  1. Effect of chemical modification on reduction and sorptive properties of chars from hydropyrolysis of coal

    Energy Technology Data Exchange (ETDEWEB)

    Stanczyk, K.; Miga, K.; Fabis, G.; Jastrzab, K. [Polskiej Akademii Nauk, Gliwice (Poland)

    1998-01-01

    Hydropyrolysis of bituminous coal and lignite as way of synthesis of adsorbents has been applied. Chemical modification of chars based on simultaneous carbonization of coal and plastics containing sulfur and nitrogen has been carried out. It was stated that modified chars exhibit better reduction and sorptive properties than non-modified and that modified adsorbents made of lignite exceed commercial ones. 7 refs., 4 figs., 3 tabs.

  2. Fifth symposium on surface mining and reclamation. NCA/BCR coal conference and Expo IV

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-01-01

    The Fifth Symposium on Surface Mining and Reclamation, sponsored by the National Coal Association and Bituminous Coal Research, Inc., was held at the Kentucky Fair and Exposition Center, Louisville, Kentucky, October 18-20, 1977. Twenty-six papers from the proceedings have been entered individually into EDB and ERA. Topics covered include spoil bank revegetation, use of aerial photography, reclamation for row crop production, hydrology, computer programs related to this work, subirrigated alluvial valley floors, reclamation on steep slopes, mountain top removal, surface mine road design, successional processes involved in reclamation, land use planning, etc. (LTN)

  3. Connection between radon emanation and some structural properties of coal-slag as building material

    International Nuclear Information System (INIS)

    Somlai, J.; Jobbagy, V.; Somlai, K.; Kovacs, J.; Nemeth, Cs.; Kovacs, T.

    2008-01-01

    Radionuclides of natural origin may accumulate in different industrial waste materials and by-products. The use of coal bottom ash or coal-slag as building material in Hungary is widespread. Because of the elevated radium content of coal-slag, high radon concentration has been detected in buildings containing coal-slag as building material. In two towns, where buildings contain coal-slag with almost the same radium concentration, the indoor radon concentrations have been found to differ significantly. In order to investigate the cause of the difference in the emanation coefficients, slag samples from the two locations were examined for grain-size distribution, density, pore volume, and specific surface. The applied methods were: gamma spectrometry for the radium concentration of the samples; Lucas cell method for the radon emanation; nitrogen absorption-desorption isotherms analyzed using the BET theory and mercury poremeter for the specific surface and pore volume. It was found that the great difference in the emanation coefficients (1.35±0.13% and 14.3±0.92%) of the coal-slag samples is primarily influenced by the pore volume and the specific surface

  4. Potential effects of surface coal mining on the hydrology of the Corral Creek area, Hanging Woman Creek coal field, southeastern Montana

    Science.gov (United States)

    McClymonds, N.E.

    1984-01-01

    The Corral Creek area of the Hanging Woman Creek coal field, 9 miles east of the Decker coal mines near the Tongue River, contains large reserves of Federal coal that have been identified for potential lease sale. A hydrologic study was conducted in the area to describe existing hydrologic systems and to study assess potential impacts of surface coal mining on local water resources. Hydrogeologic data collected indicate that aquifers are coal and sandstone beds within the Tongue River Member of the Fort Union Formation (Paleocene age) and sand and gravel in valley alluvium (Pleistocene and Holocene age). Surface-water resources are limited to a few spring-fed stock ponds in the higher parts of the area and the intermittent flow of Corral Creek near the mouth. Most of the stock ponds in the area become dry by midsummer. Mining of the Anderson coal bed would remove three stock wells and would lower the potentiometric surface within the coal and sandstone aquifers. The alluvial aquifer beneath Corral Creek and South Fork would be removed. Although mining would alter the existing hydrologic systems and remove several shallow wells, alternative ground-water supplies are available that could be developed to replace those lost by mining. (USGS)

  5. Properties of carbonisation products obtained from impregnated coal

    Czech Academy of Sciences Publication Activity Database

    Plevová, Eva; Šugárková, Věra; Kaloč, M.; Vaculíková, Lenka

    -, - (2008), s. 52-61. ISBN 978-80-248-1939-6 Grant - others:GA CŘ(CZ) GA105/00/1698 Institutional research plan: CEZ:AV0Z30860518 Keywords : chlorides * impregnation * coal Subject RIV: CC - Organic Chemistry

  6. Gas migration from closed coal mines to the surface. Risk assessment methodology and prevention means

    International Nuclear Information System (INIS)

    Pokryszka, Z.; Tauziede, Ch.; Lagny, C.; Guise, Y.; Gobillot, R.; Planchenault, J.M.; Lagarde, R.

    2005-01-01

    French law as regards renunciation to mining concessions calls for the mining operator to first undertake analyses of the risks represented by their underground mining works. The problem of gas migration to the surface is especially significant in the context of coal mines. This is because mine gas can migrate to the earth's surface, then present significant risks: explosion, suffocation or gas poisoning risks. As part of the scheduled closure of all coal mining operations in France, INERIS has drawn up, at the request of national mining operator Charbonnages de France, a general methodology for assessing the risk linked to gas in the context of closed coal mines. This article presents the principles of this methodology. An application example based on a true case study is then described. This is completed by a presentation of the preventive and monitoring resources recommended and usually applied in order to manage the risk linked to gaseous emissions. (authors)

  7. Influence of surface water accumulations of the Stupnica creek on underground coal mining in the Durdevic coal mine

    Energy Technology Data Exchange (ETDEWEB)

    Valjarevic, R; Urosevic, V

    1986-01-01

    Discusses hydrological, geological and mining conditions at the Durdevic underground coal mine. A landslide at a spoil bank dammed the creek flowing above the mine. Two exploratory boreholes (62 m and 68 m) were drilled for hydrological investigations. Water coloring techniques, chemical water analysis, measurement of underground water level and water flow were used to determine whether a sudden inrush of rainfall and accumulated surface water could endanger the mine. Underground water inflow to mine rooms varies from 110-200 m/sup 3//min, depending on the season. Diversion of the creek bed with the accumulated water and accumulation and subsequent drainage of surface water via large diameter concrete pipes were considered as possible ways of improving safety in the mine. Details of these projects are included. 4 refs.

  8. 30 CFR 761.15 - Procedures for waiving the prohibition on surface coal mining operations within the buffer zone...

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Procedures for waiving the prohibition on surface coal mining operations within the buffer zone of an occupied dwelling. 761.15 Section 761.15... surface coal mining operations within the buffer zone of an occupied dwelling. (a) This section does not...

  9. The evaluation of properties of coal mass from the viewpoint of environment

    Energy Technology Data Exchange (ETDEWEB)

    Foniok, R.; Lukes, M. [Research Mining Inst., Ostrava-Radvanice (Czechoslovakia)

    1995-12-01

    This paper deals with the evaluation of several various coal kinds from the Czech coalfields from the viewpoint of the development of thermal processes in coal mass due to their tendency towards self- ignition during storing. In such a case that no self-ignition during storing occurs, gaseous products are liberated into air, the quantity and composition of which depend upon fuel type and its temperature as well. From the environmental viewpoint, substances washed from stored coal are of a certain interest, too. In accordance with this fact, the importance of measures against self-heating of stored coal mass and the importance of a detailed observation of coal quality are concluded. The tables, which compare various coal kinds from the viewpoint of their behavior at self-ignition processes, are the integral part of this presented paper. Our greatest attention is paid to both the quantity and composition of gases being liberated in dependence upon the temperature of coal mass, and at its crushing with regard to selected methods and means of milling circuits before and explosion. Oxygen sorption by means of coal mass is also observed, being of a great importance for self-inertization of closed tanks. All the above-mentioned processes are demonstrated in form of graphic plots. Qualitative signs of coal mass are the basic means for its assessment from the viewpoint of emissions at burning/combustion, and the evaluation of explosive properties. A great attention is paid to explosion-proof means being produced in the Czech Republic. These means can be used for protection of milling circuits of power plants and heating plants or for safety systems of combustion chamber by means of insulation to secondary air main. Explosion-proof quci-acting valves, a special type of safety membrane and device for explosion suppression nip in the bud do represent the latest explosion-proof means.

  10. Memorandum of Understanding on Surface Coal Mining Operations Resulting in Placement of Excess Spoil Fills in the Waters of the United States

    Science.gov (United States)

    MOU on Surface Coal Mining Operations establishes a process for improving coordination in the review of permit applications required for surface coal mining and reclamation in waters of the United States

  11. Mechanism and Thermochemistry of Coal Char Oxidation and Desorption of Surface Oxides

    DEFF Research Database (Denmark)

    Levi, Gianluca; Causà, Mauro; Lacovig, Paolo

    2017-01-01

    The present study investigates the coal char combustion by a combination of thermochemical and X-ray photoemission spectroscopy (XPS) analyses. Thermoanalytical methods (differential thermogravimetry, differential scanning calorimetry, and temperature-programmed desorption) are used to identify...... the key reactive steps that occur upon oxidation and heating of coal char (chemisorption, structural rearrangement and switchover of surface oxides, and desorption) and their energetics. XPS is used to reveal the chemical nature of the surface oxides that populate the char surface and to monitor...... functionalities prevail. The rearrangement of epoxy during preoxidation goes together with activation of the more stable and less reactive carbon sites. Results are in good agreement with semi-lumped kinetic models of carbon oxidation, which include (1) formation of "metastable" surface oxides, (2) complex...

  12. Relocation of belt conveyors along the final slope of the Belacevac surface coal mine

    Energy Technology Data Exchange (ETDEWEB)

    Maksimovic, N; Rosic, Z

    1987-07-01

    Describes how following a landslide on the northern wing of the Belacevac surface coal mine the belt conveyor lines had to be relocated in order to assure a reliable coal supply to the Kosovo A and Kosovo B thermal power stations. The relocation was achieved in three phases with new approach cuts being made, necessitating the removal of 280,000 m/sup 3/ of overburden in the first phase and 870,000 m/sup 3/ in the second phase of the reconstruction. Illustrates the relocation of the conveyor system by means of site plans and notes that the production of coal and the removal of overburden were not interrupted during the relocation exercise. 2 refs.

  13. Restoring Forests and Associated Ecosystem Services on Appalachian Coal Surface Mines

    Science.gov (United States)

    Zipper, Carl E.; Burger, James A.; Skousen, Jeffrey G.; Angel, Patrick N.; Barton, Christopher D.; Davis, Victor; Franklin, Jennifer A.

    2011-05-01

    Surface coal mining in Appalachia has caused extensive replacement of forest with non-forested land cover, much of which is unmanaged and unproductive. Although forested ecosystems are valued by society for both marketable products and ecosystem services, forests have not been restored on most Appalachian mined lands because traditional reclamation practices, encouraged by regulatory policies, created conditions poorly suited for reforestation. Reclamation scientists have studied productive forests growing on older mine sites, established forest vegetation experimentally on recent mines, and identified mine reclamation practices that encourage forest vegetation re-establishment. Based on these findings, they developed a Forestry Reclamation Approach (FRA) that can be employed by coal mining firms to restore forest vegetation. Scientists and mine regulators, working collaboratively, have communicated the FRA to the coal industry and to regulatory enforcement personnel. Today, the FRA is used routinely by many coal mining firms, and thousands of mined hectares have been reclaimed to restore productive mine soils and planted with native forest trees. Reclamation of coal mines using the FRA is expected to restore these lands' capabilities to provide forest-based ecosystem services, such as wood production, atmospheric carbon sequestration, wildlife habitat, watershed protection, and water quality protection to a greater extent than conventional reclamation practices.

  14. Quantifying Surface Coal-Mining Patterns to Promote Regional Sustainability in Ordos, Inner Mongolia

    Directory of Open Access Journals (Sweden)

    Xiaoji Zeng

    2018-04-01

    Full Text Available Ordos became the new “coal capital” of China within a few decades since the country’s economic reform in 1978, as large-scale surface coal mining dramatically propelled its per capita GDP from being one of the lowest to one of the highest in China, exceeding Hong Kong in 2009. Surface coal-mining areas (SCMAs have continued to expand in this region during recent decades, resulting in serious environmental and socioeconomic consequences. To understand these impacts and promote regional sustainability, quantifying the spatiotemporal patterns of SCMAs is urgently needed. Thus, the main objectives of this study were to quantify the spatiotemporal patterns of SCMAs in the Ordos region from 1990 to 2015, and to examine some of the major environmental and socioeconomic impacts in the study region. We extracted the SCMAs using remote-sensing data, and then quantified their spatiotemporal patterns using landscape metrics. The loss of natural habitat and several socioeconomic indicators were examined in relation to surface coal mining. Our results show that the area of SCMAs increased from 7.12 km2 to 355.95 km2, an increase of nearly 49 times from 1990 to 2015 in the Ordos region. The number of SCMAs in this region increased from 82 to 651, a nearly seven-fold increase. In particular, Zhungeer banner (an administrative division, Yijinhuoluo banner, Dongsheng District and Dalate banner in the north-eastern part of the Ordos region had higher growth rates of SCMAs. The income gap between urban and rural residents increased along with the growth in SCMAs, undermining social equity in the Ordos region. Moreover, the rapid increase in SCMAs resulted in natural habitat loss (including grasslands, forests, and deserts across this region. Thus, we suggest that regional sustainability in Ordos needs to emphasize effective measures to curb large-scale surface coal mining in order to reduce the urban–rural income gap, and to restore degraded natural

  15. Importance of the textural characteristics of inert additives in the reduction of coal thermoplastic properties

    Energy Technology Data Exchange (ETDEWEB)

    A.M. Fernandez; C. Barriocanal; M.A. Diez; R. Alvarez [Instituto Nacional del Carbon, Oviedo (Spain)

    2010-11-15

    Seven carbonaceous materials of different origin were chosen in order to study the influence of their porous structure on the modification of the thermoplastic properties of a bituminous coal. The materials included were: two non-coking coals, a petroleum coke, coke fines, two residues from tyre recycling and a bituminous residue. The materials were heat-treated to 900{sup o}C to prevent any chemical interaction between the volatiles evolved during co-carbonization. The thermoplastic properties of blends that contained 10 wt.% of additive were measured by means of the Gieseler test. Microporosity was measured by CO{sub 2} adsorption at 273 K, whereas meso and macroporosity were determined by means of mercury porosimetry. The results of the porous structure assessment are discussed in relation to the modification of coal plasticity. 32 refs., 5 figs., 5 tabs.

  16. The effect of the textural properties of bituminous coal chars on NO emissions

    Energy Technology Data Exchange (ETDEWEB)

    Arenillas, A.; Rubiera, F.; Pis, J.J.; Jones, J.M.; Williams, A. [CSIC, Oviedo (Spain). Inst. Nacional del Carbon

    1999-11-01

    NO is the primary product of the oxidation of char nitrogen, and in some combustion processes the NO can be reduced on the char surface to give N{sub 2}O and/or N{sub 2}. In this study a range of bituminous coal (low, medium and high volatile matter content) were pyrolysed in a fixed bed reactor at various heating rates. Textural characterisation was carried out by measuring true (He) and apparent (Hg) densities and N{sub 2} (-196{degree}C) and CO{sub 2} (0{degree}C) adsorption isotherms. Pore volume distributions and surface areas were obtained for the chars studied. A thermogravimetric analyser coupled to a quadrupole mass spectrometer (TG-MS) was used to study the combustion behaviour of the samples and the nitrogen compounds evolved during temperature-programmed combustion. Results are discussed in terms of the influence of both textural properties and reactivity on NO emissions and on the heterogeneous reduction of NO. 23 refs., 8 figs., 4 tabs.

  17. Experimental Study on Properties of Methane Diffusion of Coal Block under Triaxial Compressive Stress

    Science.gov (United States)

    Zhao, Hong-Bao

    2014-01-01

    Taking the standard size coal block samples defined by ISRM as research objects, both properties of methane diffusion of coal block under triaxial compressive stress and characteristic influences caused by methane pressure were systematically studied with thermo-fluid-solid coupling with triaxial servocontrolled seepage equipment of methane-containing coal. The result shows the methane diffusion property of coal block under triaxial compressive stress was shown in four-stage as follow, first is sharply reduce stage, second is hyperbolic reduce stage, third is close to a fixed value stage, fourth stage is 0. There is a special point making the reduced rate of characteristic curve of methane diffusion speed become sharply small; the influences of shape of methane diffusion speed characteristic curve caused by methane pressure are not obvious, which only is shown in numerical size of methane diffusion speed. Test time was extended required by appear of the special point makes the reduce rate of methane diffusion speed become sharply small. The fitting four-phase relation of methane diffusion of coal block under triaxial compressive stress was obtained, and the idea is proposed that influences of the fitting four-phase relation caused by methane pressure were only shown in value of fitting parameters. PMID:25531000

  18. Fresh Properties and Flexural Strength of Self-Compacting Concrete Integrating Coal Bottom Ash

    Directory of Open Access Journals (Sweden)

    Jamaluddin Norwati

    2016-01-01

    Full Text Available This paper presents the effect of using coal bottom ash as a partial replacement of fine aggregates in self-compacting concrete (SCC on its fresh properties and flexural strength. A comparison between SCC with various replacements of fine aggregates with coal bottom ash showed that SCC obtained flexural strength decrease on increase of water cement ratio from 0.35 to 0.45. The natural sand was replaced with coal bottom ash up to 30% volumetrically. The fresh properties were investigated by slump flow, T500 spread time, L-box test and sieve segregation resistance in order to evaluate its self-compatibility by compared to control samples embed with natural sand. The results revealed that the flowability and passing ability of SCC mixtures are decreased with higher content of coal bottom ash replacement. The results also showed that the flexural strength is affected by the presence of coal bottom ash in the concrete. In addition, the water cement ratios are influence significantly with higher binder content in concrete.

  19. An analytical model of the mechanical properties of bulk coal under confined stress

    Science.gov (United States)

    Wang, G.X.; Wang, Z.T.; Rudolph, V.; Massarotto, P.; Finley, R.J.

    2007-01-01

    This paper presents the development of an analytical model which can be used to relate the structural parameters of coal to its mechanical properties such as elastic modulus and Poisson's ratio under a confined stress condition. This model is developed primarily to support process modeling of coalbed methane (CBM) or CO2-enhanced CBM (ECBM) recovery from coal seam. It applied an innovative approach by which stresses acting on and strains occurring in coal are successively combined in rectangular coordinates, leading to the aggregated mechanical constants. These mechanical properties represent important information for improving CBM/ECBM simulations and incorporating within these considerations of directional permeability. The model, consisting of constitutive equations which implement a mechanically consistent stress-strains correlation, can be used as a generalized tool to study the mechanical and fluid behaviors of coal composites. An example using the model to predict the stress-strain correlation of coal under triaxial confined stress by accounting for the elastic and brittle (non-elastic) deformations is discussed. The result shows a good agreement between the prediction and the experimental measurement. ?? 2007 Elsevier Ltd. All rights reserved.

  20. Mass spectrometric and chemometric studies of thermoplastic properties of coals. 1. Chemometry of conventional, solvent swelling and extraction data of coals

    Energy Technology Data Exchange (ETDEWEB)

    Marzec, A.; Czajkowska, S.; Moszynski, J.; Schulten, H.-R. (Polish Academy of Sciences, Gliwice (Poland). Inst. of Coal Chemistry)

    Twenty-seven coals from Carboniferous seams in Poland were studied with the aim to find links between thermoplastic properties and chemical characteristics of the coals. Three sets of data were obtained for all the coals: (1) thermoplastic properties measured using the Gieseler plastometer; (2) yields of pyridine extractables and swelling measurements for pyridine residues; (3) ultimate, proximate, and petrographic analyses. The three data sets were evaluated using chemometric techniques with the purpose of looking for significant correlations between all the data. Temperature of softening is a linear regression of pyridine extractables and hydrogen content in coals as well as of swelling data. Temperatures of maximum fluidity and resolidification are correlated with each other and with oxygen, exinite, and moisture contents of the coals as well as with the swelling data. It has been concluded that temperature of softening is a colligative property and indicates a phase transition resulting in an increase of thermal induced mobility of coal material; the energy demand of the transition is dependent on contents of bulk components of coal system that were specified in this study. Temperatures of maximum fluidity and resolidification appear to have the same chemical background; i.e. the temperatures depend on the content of the same structural units or components. However, the means of chemical characterization of coal material used in this study were not capable of identifying them. Volatile matter and petrographic composition showed rather limited value as predictive means for some (T{sub F(max)} and T{sub R}) and no predictive value for the other thermoplastic properties. 20 refs., 1 fig., 5 tabs.

  1. Studies on reactivity of coal surfaces at low temperature; Teion ni okeru sekitan hyomen no hannosei no kento

    Energy Technology Data Exchange (ETDEWEB)

    Yasuda, H.; Kaiho, M.; Yamada, O.; Soneda, Y.; Kobayashi, M.; Makino, M. [National Institute for Resources and Environment, Tsukuba (Japan)

    1996-10-28

    With an objective to learn reactivity of coal at its surface, surfaces of oxidized coal samples were investigated. Miike coal was oxidized by using {sup 18}O2 in a closed loop system. As the reaction progresses, proportion of CO2 including isotopes increased rapidly as a result of oxidation of CO sites existing in the coal and the newly generated C{sup 18}O sites. The oxidizing reaction progressed via oxygen adsorbing sites generated near the surface, and oxygen containing groups. An FT-IR analysis estimated the depth of the oxidized layer to be 10{mu}m or less from particle surface. The oxidized coal was pulverized to see its surface condition. Functional groups introduced by the oxidation enter into the vicinity of the surface in a form to desorb as CO. CO2 is trapped in inner pores. The coal surface was observed by using an atomic force microscope. No observable openings in the pore structure were discerned on the surface before the oxidation, and the structure agrees with a closed pore model. Surface image oxidized in-situ by oxygen for one hour had slight roundness, which led to a supposition of structural change, and changes in the functional group and adsorption species. 7 refs., 5 figs.

  2. CdS loaded on coal based activated carbon nanofibers with enhanced photocatalytic property

    Science.gov (United States)

    Guo, Jixi; Guo, Mingxi; Jia, Dianzeng; Song, Xianli; Tong, Fenglian

    2016-08-01

    The coal based activated carbon nanofibers (CBACFs) were prepared by electrospinning a mixture of polyacrylonitrile (PAN) and acid treated coal. Cadmium sulfide (CdS) nanoparticles loaded on CBACFs were fabricated by solvothermal method. The obtained samples were characterized by FESEM, TEM, and XRD. The results reveal that the CdS nanoparticles are homogeneously dispersed on the surfaces of CBACFs. The CdS/CBACFs nanocomposites exhibited higher photoactivity for photodegradation of methyl blue (MB) under visible light irradiation than pure CdS nanoparticles. CBACFs can be used as low cost support materials for the preparation of nanocomposites with high photocatalytic activity.

  3. Finite element modeling of surface subsidence induced by underground coal mining

    International Nuclear Information System (INIS)

    Su, D.W.H.

    1992-01-01

    The ability to predict the effects of longwall mining on topography and surface structures is important for any coal company in making permit applications and anticipating potential mining problems. The sophisticated finite element model described and evaluated in this paper is based upon five years of underground and surface observations and evolutionary development of modeling techniques and attributes. The model provides a very powerful tool to address subsidence and other ground control questions. The model can be used to calculate postmining stress and strain conditions at any horizon between the mine and the ground surface. This holds the promise of assisting in the prediction of mining-related hydrological effects

  4. Debilitating lung disease among surface coal miners with no underground mining tenure.

    Science.gov (United States)

    Halldin, Cara N; Reed, William R; Joy, Gerald J; Colinet, Jay F; Rider, James P; Petsonk, Edward L; Abraham, Jerrold L; Wolfe, Anita L; Storey, Eileen; Laney, A Scott

    2015-01-01

    To characterize exposure histories and respiratory disease among surface coal miners identified with progressive massive fibrosis from a 2010 to 2011 pneumoconiosis survey. Job history, tenure, and radiograph interpretations were verified. Previous radiographs were reviewed when available. Telephone follow-up sought additional work and medical history information. Among eight miners who worked as drill operators or blasters for most of their tenure (median, 35.5 years), two reported poor dust control practices, working in visible dust clouds as recently as 2012. Chest radiographs progressed to progressive massive fibrosis in as few as 11 years. One miner's lung biopsy demonstrated fibrosis and interstitial accumulation of macrophages containing abundant silica, aluminum silicate, and titanium dust particles. Overexposure to respirable silica resulted in progressive massive fibrosis among current surface coal miners with no underground mining tenure. Inadequate dust control during drilling/blasting is likely an important etiologic factor.

  5. Slag Behavior in Gasifiers. Part I: Influence of Coal Properties and Gasification Conditions

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2013-02-01

    Full Text Available In the entrained-flow gasifiers used in integrated gasification combined cycle (IGCC plants, the majority of mineral matter transforms to liquid slag on the wall of the gasifier and flows out the bottom. However, a small fraction of the mineral matter is entrained (as fly ash with the raw syngas out of the gasifier to downstream processing. This molten/sticky fly ash could cause fouling of the syngas cooler. To improve gasification availability through better design and operation of the gasification process, a better understanding of slag behavior and the characteristics of the slagging process is needed. Char/ash properties, gas compositions in the gasifier, the gasifier wall structure, fluid dynamics, and plant operating conditions (mainly temperature and oxygen/carbon ratio all affect slagging behavior. Because coal has varying ash content and composition, different operating conditions are required to maintain the slag flow and limit problems downstream. In Part I, we review the main types and the operating conditions of entrained-flow gasifiers and coal properties used in IGCC plants; we identify and discuss the key coal ash properties and the operating conditions impacting slag behavior; finally, we summarize the coal quality criteria and the operating conditions in entrained-flow gasifiers. In Part II, we discuss the constitutive modeling related to the rheological studies of slag flow.

  6. Change in electric and dielectric properties of some Australian coals during the processes of pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Zubkova, V.; Prezhdo, V. [Institute of Chemistry, Jan Kochanowski University, 5 Checinska Street, 25-020 Kielce (Poland)

    2006-03-01

    The investigation of change in electric and dielectric properties of Australian coals was carried out during their pyrolysis. The relation between the increase of the tangent of dielectric losses and electrical resistivity in the pre-plastic state of pyrolysis was established. It was shown that at the pre-plastic stage of pyrolysis, when the organic coal mass is in the glassy state, the decrease in value of electrical resistivity is caused by the increase in rotational movement of segments of macromolecules as evidenced by the increase in tg{delta} parameter. The character of change in curves r=f(T{sup o}) and tg{delta}=f(T{sup o}C) in the pre-plastic state of the process of coal pyrolysis predetermines the values of parameters of coke durability. (author)

  7. Effects of process parameters and ash on the adsorption properties of activated carbon from coals

    International Nuclear Information System (INIS)

    Gao, F.; Han, L.

    2013-01-01

    super-activated carbon was prepared from three representative shanxi coals, i.e. datong bituminous coal, yangquan anthracite and jincheng anthracite by KOH activation. The optimum parameters were obtained by comparing CCl/sub 4/ absorption values of activated carbon (ac). In addition, pristine coal and ac were deashed by acid washing, respectively. The effect of ash content on the adsorption properties of ac was studied. the results indicate that CCl/sub 4/ adsorption value of ac from yangquan anthracite with deashing treatment reaches up to 3301 mg/g when the activated temperature, activated time and ratio of alkali to carbon are 1830 degree C, 60 min and 5/1, respectively. (author)

  8. The largest US coal acquisition takes shape

    International Nuclear Information System (INIS)

    Carter, R.A.

    1998-01-01

    The midyear purchase of Arco's US coal properties for 1.14 billion dollars gave Arch coal, Inc. (ACI) a string of surface and underground mines stretching from Wyoming's Powder River Basin to the coalfields of central Utah. The transaction created a new entity, Arch Western Resources LLC. The article describes operations at Black Thunder and Coal Creek surface mines and SUFCO, Skyline, Dugout Canyon and West Elk longwall mines. 4 photos

  9. [Soil organic pollution characteristics and microbial properties in coal mining areas of Mentougou].

    Science.gov (United States)

    Jia, Jian-Li; Zhang, Yue; Wang, Chen; Li, Dong; Liu, Bo-Wen; Liu, Ying; Zhao, Le; Yang, Si-Qi

    2011-03-01

    Soil micro-ecosystem including organic pollution characteristics, basic physicochemical parameters, and microbial properties was analyzed which contaminated with organic pollutants in coal mining area. Results showed that the organic pollution level in coal mining area soils distributed from 0.4 to 1.5 mg/g dry soil, which was 1. 5-6 times as much as the background sample. Furthermore, the column chromatography and GC-MS analysis revealed that content of lightly components including saturated and aromatic hydrocarbons exceeded 40%, specifically was alkenes (> C15), hydrocarbon derivatives, and a small amount aromatic hydrocarbons. Totally, the components of organic pollutants extracted in soils were similar to which in coal gangue samples, illustrating the source of soil pollution to a certain extent in coal mining areas. The physicochemical factors such as nutrient level and moisture contents were not conducive to the growth and reproduction of microbe except pH level, which might show inhibition to microbial activities. Microbial density of pollutant soils in coal mining areas was totally low, with specific amount 10(4)-10(5) cell/g dry soil and FDA activity 2.0-2.9 mg/(g x min). Generally, the microbial density and activity were decreased as the enhancing pollution level. However, in-depth analysis was needed urgently because of the complex impact of environmental conditions like pH, moisture, and nutrition.

  10. Abating coal tar seepage into surface water bodies using sheet piles with sealed interlocks

    International Nuclear Information System (INIS)

    Collingwood, B.I.; Boscardin, M.D.; Murdock, R.F.

    1995-01-01

    A former coal tar processing facility processed crude coal tar supplied from manufactured gas plants in the area. Coal-tar-contaminated ground water from the site was observed seeping through an existing timber bulkhead along a tidal river and producing a multicolored sheen on the surface of the river. As part of a short-term measure to abate the seepage into the river, 64-m long anchored sheet pile wall with sheet pile wing walls at each end was constructed inland of the of the timber bulkhead. The sheet piles extended to low-permeability soils at depth and the interlocks of the sheet piles were provided with polyurethane rubber seals. Based on postconstruction observations for leakage and sheens related to leakage, the steel sheet piles with polyurethane rubber interlock seals appeared to provide a successful seal and abate coal-tar-contaminated ground water seepage into the river. The tie rod penetration sealing proved to be a more problematic detail, but through several postconstruction grouting episodes, an effective seal was produced

  11. Temperature dependence of nuclear surface properties

    International Nuclear Information System (INIS)

    Campi, X.; Stringari, S.

    1982-01-01

    Thermal properties of nuclear surface are investigated in a semi-infinite medium. Explicit analytical expression are given for the temperature dependence of surface thickness, surface energy and surface free energy. In this model the temperature effects depend critically on the nuclear incompressibility and on the shape of the effective mass at the surface. To illustrate the relevance of these effects we made an estimate of the temperature dependence of the fission barrier height. (orig.)

  12. Lunar surface engineering properties experiment definition

    Science.gov (United States)

    Mitchell, J. K.; Goodman, R. E.; Hurlbut, F. C.; Houston, W. N.; Willis, D. R.; Witherspoon, P. A.; Hovland, H. J.

    1971-01-01

    Research on the mechanics of lunar soils and on developing probes to determine the properties of lunar surface materials is summarized. The areas of investigation include the following: soil simulation, soil property determination using an impact penetrometer, soil stabilization using urethane foam or phenolic resin, effects of rolling boulders down lunar slopes, design of borehole jack and its use in determining failure mechanisms and properties of rocks, and development of a permeability probe for measuring fluid flow through porous lunar surface materials.

  13. Effects of Heating Rate on the Dynamic Tensile Mechanical Properties of Coal Sandstone during Thermal Treatment

    Directory of Open Access Journals (Sweden)

    Ming Li

    2017-01-01

    Full Text Available The effects of coal layered combustion and the heat injection rate on adjacent rock were examined in the process of underground coal gasification and coal-bed methane mining. Dynamic Brazilian disk tests were conducted on coal sandstone at 800°C and slow cooling from different heating rates by means of a Split Hopkinson Pressure Bar (SHPB test system. It was discovered that thermal conditions had significant effects on the physical and mechanical properties of the sandstone including longitudinal wave velocity, density, and dynamic linear tensile strength; as the heating rates increased, the thermal expansion of the sandstone was enhanced and the damage degree increased. Compared with sandstone at ambient temperature, the fracture process of heat-treated sandstone was more complicated. After thermal treatment, the specimen had a large crack in the center and cracks on both sides caused by loading; the original cracks grew and mineral particle cracks, internal pore geometry, and other defects gradually appeared. With increasing heating rates, the microscopic fracture mode transformed from ductile fracture to subbrittle fracture. It was concluded that changes in the macroscopic mechanical properties of the sandstone were result from changes in the composition and microstructure.

  14. Nitric oxide reduction in coal combustion: role of char surface complexes in heterogeneous reactions

    Energy Technology Data Exchange (ETDEWEB)

    Arenillas, A.; Rubiera, F.; Pis, J.J. [Instituto Nacional del Carbon, CSIC, Oviedo (Spain)

    2002-12-15

    Nitrogen oxides are one of the major environmental problems arising from fossil fuel combustion. Coal char is relatively rich in nitrogen, and so this is an important source of nitrogen oxides during coal combustion. However, due to its carbonaceous nature, char can also reduce NO through heterogeneous reduction. The objectives of this work were on one hand to compare NO emissions from coal combustion in two different types of equipment and on the other hand to study the influence of char surface chemistry on NO reduction. A series of combustion tests were carried out in two different scale devices: a thermogravimetric analyzer coupled to a mass spectrometer and an FTIR (TG-MS-FTIR) and a fluidized bed reactor with on-line battery of analyzers. According to the results obtained, it can be said that the TG-MS-FTIR system provides valuable information about NO heterogeneous reduction and it can give good trends of the behaviour in other combustion equipments, i.e. fluidized bed combustors. It has been also pointed out that NO-char interaction depends to a large extent on temperature. In the low-temperature range NO heterogeneous reduction seems to be controlled by the evolution of surface complexes. In the high-temperature range a different mechanism is involved in NO heterogeneous reduction, the nature of the carbon matrix being a key factor. 27 refs., 6 figs., 1 tab.

  15. Nitric oxide reduction in coal combustion: role of char surface complexes in heterogeneous reactions.

    Science.gov (United States)

    Arenillas, Ana; Rubiera, Fernando; Pis, José J

    2002-12-15

    Nitrogen oxides are one of the major environmental problems arising from fossil fuel combustion. Coal char is relatively rich in nitrogen, and so this is an important source of nitrogen oxides during coal combustion. However, due to its carbonaceous nature, char can also reduce NO through heterogeneous reduction. The objectives of this work were on one hand to compare NO emissions from coal combustion in two different types of equipment and on the other hand to study the influence of char surface chemistry on NO reduction. A series of combustion tests were carried out in two different scale devices: a thermogravimetric analyzer coupled to a mass spectrometer and an FTIR (TG-MS-FTIR) and a fluidized bed reactor with an on line battery of analyzers. The TG-MS-FTIR system was also used to perform a specific study on NO heterogeneous reduction reactions using chars with different surface chemistry. According to the results obtained, it can be said that the TG-MS-FTIR system provides valuable information about NO heterogeneous reduction and it can give good trends of the behavior in other combustion equipments (i.e., fluidized bed combustors). It has been also pointed out that NO-char interaction depends to a large extent on temperature. In the low-temperature range (800 degrees C), a different mechanism is involved in NO heterogeneous reduction, the nature of the carbon matrix being a key factor.

  16. Disposing of coal combustion residues in inactive surface mines: Effects on water quality

    International Nuclear Information System (INIS)

    Kim, A.G.; Ackman, T.E.

    1994-01-01

    The disposal of coal combustion residues (CCR) in surface and underground coal mines can provide a stable, low-maintenance alternative to landfills, benefiting the mining and electric power industries. The material may be able to improve water quality at acid generating abandoned or reclaimed coal mine sites. Most combustion residues are alkaline, and their addition to the subsurface environment could raise the pH, limiting the propagation of pyrite oxidizing bacteria and reducing the rate of acid generation. Many of these CCR are also pozzolanic, capable of forming cementitious grouts. Grouts injected into the buried spoil may decrease its permeability and porosity, diverting water away from the pyritic material. Both mechanisms, alkaline addition and water diversion, are capable of reducing the amount of acid produced at the disposal site. The US Bureau of Mines is cooperating in a test of subsurface injection of CCR into a reclaimed surface mine. Initially, a mixture of fly ash, lime, and acid mine drainage (AMD) sludge was injected. Lime was the source of calcium for the formation of the pozzolanic grout. Changes in water quality parameters (pH, acidity, anions, and trace metals) in water samples from wells and seeps indicate a small but significant improvement after CCR injection. Changes in the concentration of heavy metals in the water flowing across the site were apparently influenced by the presence of flyash

  17. LANDSAT remote sensing: observations of an Appalachian mountaintop surface coal mining and reclamation operation

    International Nuclear Information System (INIS)

    1979-10-01

    The potential benefits of using LANDSAT remote sensing data by state agencies as an aide in monitoring surface coal mining operations are reviewed. A mountaintop surface mine in eastern Kentucky was surveyed over a 5 year period using satellite multispectral scanner data that were classified by computer analyses. The analyses were guided by aerial photography and by ground surveys of the surface mines procured in 1976. The application of the LANDSAT data indicates that: (1) computer classification of the various landcover categories provides information for monitoring the progress of surface mining and reclamation operations, (2) successive yearly changes in barren and revegetated areas can be qualitatively assessed for surface mines of 100 acres or more of disrupted area, (3) barren areas consisting of limestone and shale mixtures may be recognized, and revegetated areas in various stages of growth may be identified against the hilly forest background

  18. Study on the submicron and micron morphology and the properties of poor bituminous coal burnout

    Energy Technology Data Exchange (ETDEWEB)

    Pei-Fang Fu; Huai-Chun Zhou; Qing-Yan Fang; Hai Yao; Jianrong Qiu; Minghou Xu [Huazhong University of Science and Technology, Wuhan (China). State Key Laboratory of Coal Combustion

    2007-05-15

    Carbon burnout and its reaction mechanism have been widely focused on in the past decades. The properties of burnout, submicron and micron morphology and the reaction mechanism of poor bituminous coal/char (PBC) in a W-shaped power plant boiler was studied and was compared with those in DTF and in TGA, which showed that the degree of PBC burnout in TGA at 1450{sup o}C was greater than or approximately equal to that in a W-shaped boiler, and that the complexity of the reactions among residual char, oxygen and SiO{sub 2} did not seem to result in mass loss in TGA, although the weight percentage of the residual char in ash decreased from 33% ad (air dry basis) at 900{sup o}C to 9% and at 1450{sup o}C. According to the distribution of pores and the properties of the char burnout, the char can be simply categorized into three classes: char burnout easy, char burnout difficult and char burnout very difficult. The differences of the reaction mechanism must be considered while predicting the burning rate and degree of char burnout in a full-scale boiler by making use of experimental results from TGA and DTF. A different char particle contains markedly different amount of carbons, but for a special char particle, the ratio of carbon to ash is generally constant, and an ash shell does not exist on the char surface. The fusion mineral matter composing of C-O-Si-Al is amorphous, not in the form of Al{sub 2}O{sub 3} and SiO{sub 2} above 1450{sup o}C.

  19. Surface active monomers synthesis, properties, and application

    CERN Document Server

    Borzenkov, Mykola

    2014-01-01

    This brief includes information on the background?of and development of synthesis of various types of surface active monomers. The authors explain the importance of utilization of surface active monomers for creation of surface active polymers? and the various biomedical applications of such compounds . This brief introduces techniques for the synthesis of novel types of surface active monomers, their colloidal and polymerizable properties and application for needs of medicine and biology.

  20. Assessment of burned coal shale properties based on cyclic load

    Science.gov (United States)

    Grygierek, Marcin; Kalisz, Piotr; Pacześniowski, Krzysztof; Pytlik, Andrzej; Zięba, Magdalena

    2018-04-01

    Road surfaces that are subjected to cyclic loads generated by vehicle wheels must meet the requirements concerning the durability in the assumed period of use. The durability of the layered pavement construction systems depends on the value and frequency of the load as well as on the mechanical features of its individual layers. Layers of unbound, mechanically stabilized mixtures are a significant aspect of surfaces that are susceptible. Mixtures of this type can be applied both to the subgrade layers as well as to the bottom pavement layers, including the improved course. Considering the cyclic nature of the load on the surface of the entire system, mechanically stabilized layers are subject to continuous, but slow, densification during the period of use, which results in the formation of permanent deformations and so-called structural ruts. Post-mining waste is frequently used in road construction. which is the so-called burned shale that can be used for the bottom layers of the surface and layers of the improved subgrade (soil replacement). This material was the subject of the analysis. The evaluation was based mainly on the results of pilot studies covering cyclic loads of the layer/course made of the so-called red shale. The applied research method was aimed at preliminary assessment of its suitability for the assessment of the behaviour of the disintegrated medium under the conditions of test loads simulating the movement of vehicles.

  1. Assessment of burned coal shale properties based on cyclic load

    Directory of Open Access Journals (Sweden)

    Grygierek Marcin

    2018-01-01

    Full Text Available Road surfaces that are subjected to cyclic loads generated by vehicle wheels must meet the requirements concerning the durability in the assumed period of use. The durability of the layered pavement construction systems depends on the value and frequency of the load as well as on the mechanical features of its individual layers. Layers of unbound, mechanically stabilized mixtures are a significant aspect of surfaces that are susceptible. Mixtures of this type can be applied both to the subgrade layers as well as to the bottom pavement layers, including the improved course. Considering the cyclic nature of the load on the surface of the entire system, mechanically stabilized layers are subject to continuous, but slow, densification during the period of use, which results in the formation of permanent deformations and so-called structural ruts. Post-mining waste is frequently used in road construction. which is the so-called burned shale that can be used for the bottom layers of the surface and layers of the improved subgrade (soil replacement. This material was the subject of the analysis. The evaluation was based mainly on the results of pilot studies covering cyclic loads of the layer/course made of the so-called red shale. The applied research method was aimed at preliminary assessment of its suitability for the assessment of the behaviour of the disintegrated medium under the conditions of test loads simulating the movement of vehicles.

  2. Surface composition and surface properties of water hyacinth ...

    African Journals Online (AJOL)

    Surface composition and surface properties of water hyacinth ( Eichhornia ... (2/1, v/v) followed by ethanol, using Fourier Transform Infra-red (FT-IR) spectroscopy, ... polar organic solvents and non-polar n-alkane hydrocarbons is discussed.

  3. The unusual properties of beryllium surfaces

    International Nuclear Information System (INIS)

    Stumpf, R.; Hannon, J.B.

    1994-01-01

    Be is a ''marginal metal.'' The stable phase, hcp-Be, has a low Fermi-level density of states and very anisotropic structural and elastic properties, similar to a semiconductor's. At the Be(0001) surface, surface states drastically increase the Fermi-level density of states. The different nature of bonding in bulk-Be and at the Be(0001) surface explains the large outward relaxation. The presence of surface states causes large surface core-level shifts by inducing a higher electrostatic potential in the surface layers and by improving the screening at the surface. The authors experimental and theoretical investigations of atomic vibrations at the Be(0001) surface demonstrate clearly that Be screening of atomic motion by the surface states makes the surface phonon dispersion fundamentally different from that of the bulk. Properties of Be(0001) are so different from those of the bulk that the surface can be considered a new ''phase'' of beryllium with unique electronic and structural characteristics. For comparison they also study Be(11 bar 20), a very open surface without important surface states. Be(11 bar 20) is the only clean s-p metal surface known to reconstruct (1 x 3 missing row reconstruction)

  4. Dielectric properties of lunar surface

    Science.gov (United States)

    Yushkova, O. V.; Kibardina, I. N.

    2017-03-01

    Measurements of the dielectric characteristics of lunar soil samples are analyzed in the context of dielectric theory. It has been shown that the real component of the dielectric permittivity and the loss tangent of rocks greatly depend on the frequency of the interacting electromagnetic field and the soil temperature. It follows from the analysis that one should take into account diurnal variations in the lunar surface temperature when interpreting the radar-sounding results, especially for the gigahertz radio range.

  5. Investigations of the surface tension of coal ash slags under gasification conditions; Untersuchungen zur Oberflaechenspannung von Kohleschlacken unter Vergasungsbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Melchior, Tobias

    2011-10-26

    In the context of CO{sub 2}-emission-induced global warming, greenhouse gases resulting from the production of electricity in coal-fired power plants gain increasing attention. One possible way to reduce such emissions is to gasify coal instead of burning it. The corresponding process is referred to as Integrated Gasification Combined Cycle and allows for the separation of CO{sub 2} before converting a synthesis gas into electrical energy. However, further improvements in efficiency and availability of this plant technology are needed to render the alternative generation of electricity sensible from an economic point of view. One corresponding approach introduces hot gas cleaning facilities to the gasification plant which guarantee a removal of slag particles from the synthesis gas at high temperatures. The development of such filters depends on the availability of data on the material properties of the coal ash slags to be withdrawn. In this respect, the surface tension is a relevant characteristic. Currently, the surface tension of real coal ash slags as well as of synthetic model systems was measured successfully by means of the sessile drop and the maximum bubble pressure method. With regard to the sessile drop technique, those experiments were conducted in a gasification-like atmosphere at temperatures of up to 1500 C. Furthermore, the pressure inside the experimental vessel was raised to 10 bar in order to allow for deriving the influence of this variable on the surface tension. In contrast, maximum bubble pressure trials were realised at atmospheric pressure while the gas atmosphere assured inert conditions. For performing sessile drop measurements, a corresponding apparatus was set up and is described in detail in this thesis. Three computer algorithms were employed to calculate surface tensions out of the photos of sessile drops and their individual performance was evaluated. A very good agreement between two of the codes was found while the third one

  6. Defined wetting properties of optical surfaces

    Science.gov (United States)

    Felde, Nadja; Coriand, Luisa; Schröder, Sven; Duparré, Angela; Tünnermann, Andreas

    2017-10-01

    Optical surfaces equipped with specific functional properties have attracted increasing importance over the last decades. In the light of cost reduction, hydrophobic self-cleaning behavior is aspired. On the other side, hydrophilic properties are interesting due to their anti-fog effect. It has become well known that such wetting states are significantly affected by the surface morphology. For optical surfaces, however, this fact poses a problem, as surface roughness can induce light scattering. The generation of optical surfaces with specific wetting properties, hence, requires a profound understanding of the relation between the wetting and the structural surface properties. Thus, our work concentrates on a reliable acquisition of roughness data over a wide spatial frequency range as well as on the comprehensive description of the wetting states, which is needed for the establishment of such correlations. We will present our advanced wetting analysis for nanorough optical surfaces, extended by a vibration-based procedure, which is mainly for understanding and tailoring the wetting behavior of various solid-liquid systems in research and industry. Utilizing the relationships between surface roughness and wetting, it will be demonstrated how different wetting states for hydrophobicity and hydrophilicity can be realized on optical surfaces with minimized scatter losses.

  7. Metrology and properties of engineering surfaces

    CERN Document Server

    Greenwood, J; Chetwynd, D

    2001-01-01

    Metrology and Properties of Engineering Surfaces provides in a single volume a comprehensive and authoritative treatment of the crucial topics involved in the metrology and properties of engineering surfaces. The subject matter is a central issue in manufacturing technology, since the quality and reliability of manufactured components depend greatly upon the selection and qualities of the appropriate materials as ascertained through measurement. The book can in broad terms be split into two parts; the first deals with the metrology of engineering surfaces and covers the important issues relating to the measurement and characterization of surfaces in both two and three dimensions. This covers topics such as filtering, power spectral densities, autocorrelation functions and the use of Fractals in topography. A significant proportion is dedicated to the calibration of scanning probe microscopes using the latest techniques. The remainder of the book deals with the properties of engineering surfaces and covers a w...

  8. The prediction and representation of phase equilibria and physicochemical properties in complex coal ash slag systems

    Energy Technology Data Exchange (ETDEWEB)

    E. Jak; A. Kondratiev; S. Christie; P.C. Hayes [Centre for Coal in Sustainable Development (CCSD), Brisbane (Australia)

    2003-07-01

    A range of problems in coal utilisation technologies, including ash slag flow in slagging gasifiers, deposit formation, slagging, fouling, fusibility tests, fluxing, blending etc, are related to the melting behaviour of the mineral matter in the coal. To assist with solving these practical issues i) thermodynamic modelling of phase equilibria, and ii) viscosity modelling studies are being undertaken at the Pyrometallurgy Research Centre (The University of Queensland, Australia) with support from the Collaborative Research Centre for Coal in Sustainable Development (CCSD). The thermodynamic modelling has been carried out using the computer system FactSage, which is used for the calculation of multi-phase slag / solid / gas / matte / alloy / salt equilibria in multi-component systems of industrial interest. A modified quasi-chemical solution model is used for the liquid slag phase. New model optimisations have been carried out, which have significantly improved the accuracy of the thermodynamic models for coal combustion processes. Viscosity modelling, using a modified Urbain formalism, is carried out in conjunction with FactSage calculations to predict the viscosities of fully liquid as well as heterogeneous, partly crystallised slags. Custom designed software packages are developed using these fundamental models for wider use by industrial researchers and engineers, and for incorporation as process control modules. The new custom-designed computer software package can be used to produce limiting operability diagrams for slag systems. These diagrams are used to describe phase equilibria and physico-chemical properties in complex slag systems. The approach is illustrated with calculations on the system SiO{sub 2}-Al{sub 2}O{sub 3}-FeO-Fe{sub 2}O{sub 3}-CaO at metallic iron saturation, slags produced in coal slagging gasifiers. 28 refs., 7 figs., 1 tab.

  9. Design properties of coal liquids: edited workshop proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Brinkman, D.W.; Reilly, M.J. (eds.)

    1981-08-01

    The advent of synfuels will require a large measurement and modeling effort of new thermodynamic and physical properties. These data are required for the economic design and operation of proposed synfuel plants. The areas of data need are well defined. The pace of measurement will be restricted by laboratory availability. The cost for the required data and for their correlation and modeling will be substantial. And finally, the cost of doing all this work will be substantial. The plants we are talking about are energy plants and synfuel plants. They are energy intensive plants, and as such, they offer the prospects for a great deal of energy saving. To do so requires good data. In those critical areas where we start hunting the energy hogs, we will find that with +-20% data those hogs are pretty well hidden.

  10. Physiocochemical properties of blood serum proteins of coal miners

    Energy Technology Data Exchange (ETDEWEB)

    Nandakova, V N; Zemliakova, L F; Sukhanov, V V; Min' ko, L A

    1979-07-01

    Using disk electrophoresis in the polyacrylamide gel, blood serum proteins were studied in miners working under conditions of the combine (the control group) and drilling-and-blasting (the contact with carbon oxide, nitrogen oxides) driving technique under normal temperature conditions. 26 to 27 protein fractions characterized by mobility, thermolability under definite conditions of the experiment and the contitative content were obtained. It is shown that the contact with carbon oxide and nitrogen oxides causes changes in the properties of certain proteins (II3, globulins - 2 alpha 1, 3 alpha 1, 2 beta, 2 alpha 2, 5 alpha 2, 6 alpha 2, 7 alpha 2) of miners' blood serum. Some of these proteins are supposed to participate in the adaptation reactions of the organism.

  11. Use of a three dimensional network model to predict equilibrium desaturation properties of coal filter cakes

    Energy Technology Data Exchange (ETDEWEB)

    Qamar, I.; Bayles, G.A.; Tierney, J.W.; Chiang, S.-H.; Klinzing, G.E.

    1987-01-01

    A three dimensional bond-flow correlated network model has been successfully used to calculate equilibrium desaturation curves for coal filter cakes. A simple cubic lattice with the pore sizes correlated in the direction of macroscopic flow is used as the network. A new method of pore volume assignment is presented in which the pore volume occupied by the large pores (which give rise to capillary pressures less than a calculated critical value) is assigned to the nodes and the rest is distributed to the bonds according to an experimentally determined micrographic pore size distribution. Equilibrium desaturation curves for -32 mesh, -200 mesh and -100 + 200 mesh coal cakes (Pittsburgh Seam coal), formed with distilled water have been calculated. A bond flow correlation factor, F/sub c/ is introduced to account for channeling of the displacing fluid through high volume, low resistance flow paths - a phenomenon which is displayed by many real systems. It is determined that a single value of 0.6 for F/sub c/ is required for -32 mesh and -200 mesh coals. However, for -100 + 200 mesh coal, where all small as well as large particles have been removed, a value of 1.0 is required. The results of six -32 mesh cakes formed with surfactants show that the effect of surfactants can be accounted for by modifying one of the model parameters, the entry diameter correction. A correlation is presented to estimate the modified correction using experimentally determined surface tension and contact angle values. Further, the predicted final saturations agree with the experimental values within an average absolute error of 5%. 16 refs., 11 figs., 2 tabs.

  12. Effect of coal mine dust and clay extracts on the biological activity of the quartz surface

    Energy Technology Data Exchange (ETDEWEB)

    Stone, V.; Jones, R.; Rollo, K.; Duffin, R.; Donaldson, K.; Brown, D.M. [Napier University, Edinburgh (United Kingdom). School of Life Science

    2004-04-01

    Modification of the quartz surface by aluminum salts and metallic iron have been shown to reduce the biological activity of quartz. This study aimed to investigate the ability of water soluble extracts of coal mine dust (CMD), low aluminum clays (hectorite and montmorillonite) and high aluminum clays (attapulgite and kaolin) to inhibit the reactivity of the quartz surface. DQ12 induced significant haemolysis of sheep erythrocytes in vitro and inflammation in vivo as indicated by increases in the total cell numbers, neutrophil cell numbers, MIP-2 protein and albumin content of bronchoalveolar lavage (BAL) fluid. Treatment of DQ12 with CMD extract prevented both haemolysis and inflammation. Extracts of the high aluminum clays (kaolin and attapulgite) prevented inhibition of DQ12 induced haemolysis, and the kaolin extract inhibited quartz driven inflammation. DQ12 induced haemolysis by coal mine dust and kaolin extract could be prevented by pre-treatment of the extracts with a cation chellator. Extracts of the low aluminum clays (montmorillonite and hectorite) did not prevent DQ12 induced haemolysis, although the hectorite extract did prevent inflammation. These results suggest that CMD, and clays both low and rich in aluminum, all contain soluble components (possibly cations) capable of masking the reactivity of the quartz surface.

  13. Micostructural and mechanical properties of geopolymers synthesised from three coal fly ashes from South Africa

    CSIR Research Space (South Africa)

    Dludlu, MK

    2017-01-01

    Full Text Available In this study, coal fly ashes (CFAs) from three different boiler sites in South Africa, Eskom (E coal fly ash), George Mukhari Academic Hospital (GMH coal fly ash), and KarboChem (KBC coal fly ash), were used to produce geopolymers. The coal fly...

  14. Summary of fish and wildlife information needs to surface mine coal in the United States. Part 3. A handbook for meeting fish and wildlife information needs to surface mine coal: OSM Region V. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hinkle, C.R.; Ambrose, R.E.; Wenzel, C.R.

    1981-02-01

    This report contains information to assist in protecting, enhancing, and reducing impacts to fish and wildlife resources during surface mining of coal. It gives information on the premining, mining, reclamation and compliance phases of surface mining. This volume is specifically for the states of Washington, Idaho, Montana, North Dakota, South Dakota, Wyoming, Oregon, California, Nevada, Utah, Colorado, Arizona and New Mexico.

  15. Physical and Chemical Properties of Coal Bottom Ash (CBA) from Tanjung Bin Power Plant

    Science.gov (United States)

    Izzati Raihan Ramzi, Nurul; Shahidan, Shahiron; Zulkhairi Maarof, Mohamad; Ali, Noorwirdawati

    2016-11-01

    The objective of this study is to determine the physical and chemical characteristics of Coal Bottom Ash (CBA) obtained from Tanjung Bin Power Plant Station and compare them with the characteristics of natural river sand (as a replacement of fine aggregates). Bottom ash is the by-product of coal combustion during the electricity generating process. However, excess bottom ash production due to the high production of electricity in Malaysia has caused several environmental problems. Therefore, several tests have been conducted in order to determine the physical and chemical properties of bottom ash such as specific gravity, density, particle size distribution, Scanning Electron Microscopic (SEM) and X- Ray Fluorescence (XRF) in the attempt to produce sustainable material from waste. The results indicated that the natural fine aggregate and coal bottom ash have very different physical and chemical properties. Bottom ash was classified as Class C ash. The porous structure, angular and rough texture of bottom ash affected its specific gravity and particle density. From the tests, it was found that bottom ash is recommended to be used in concrete as a replacement for fine aggregates.

  16. Atlas of western surface-mined lands: coal, uranium, and phosphate

    International Nuclear Information System (INIS)

    Evans, A.K.; Uhleman, E.W.; Eby, P.A.

    1978-01-01

    The atlas contains available information on all coal, uranium, and phosphate surface mines in excess of 10 acres that were in operation prior to 1976 in the western 11 contiguous states plus North Dakota and South Dakota. It is assembled in a format that allows a systematic and comprehensive review of surface-mined lands so that appropriate areas can be selected for intensive biological assessment of natural and man-induced revegetation and refaunation. For each identified mine, the following information has been obtained wherever possible: geographic location and locating instructions, operator and surface and subsurface ownership, summary of the mining plan and methods, summary of the reclamation plan and methods, dates of operation, area affected by mining activities, reclamation history, where applicable, and current land use and vegetation conditions

  17. Copyrolysis of Biomass and Coal: A Review of Effects of Copyrolysis Parameters, Product Properties, and Synergistic Mechanisms

    Science.gov (United States)

    2016-01-01

    Concerns in the last few decades regarding the environmental and socioeconomic impacts of the dependence on fossil fuels have resulted in calls for more renewable and alternative energy sources. This has led to recent interest in copyrolysis of biomass and coal. Numerous reviews have been found related to individual pyrolysis of coal and biomass. This review deals mainly with the copyrolysis of coal and biomass and then compares their results with those obtained using coal and biomass pyrolysis in detail. It is controversial whether there are synergistic or additive behaviours when coal and biomass are blended during copyrolysis. In this review, the effects of reaction parameters such as feedstock types, blending ratio, heating rate, temperature, and reactor types on the occurrence of synergy are discussed. Also, the main properties of the copyrolytic products are pointed out. Some possible synergistic mechanisms are also suggested. Additionally, several outlooks based on studies in the literature are also presented in this paper. PMID:27722171

  18. Development of the first coal seam gas exploration program in Indonesia: Reservoir properties of the Muaraenim Formation, south Sumatra

    Energy Technology Data Exchange (ETDEWEB)

    Sosrowidjojo, I.B. [R and D Centre for Oil and Gas Technology, LEMIGAS, Jakarta (Indonesia); Saghafi, A. [CSIRO Energy Technology, P O Box 330, Newcastle, NSW, 2300 (Australia)

    2009-09-01

    The Late Miocene Muaraenim Formation in southern Sumatra contains thick coal sequences, mostly of low rank ranging from lignite to sub-bituminous, and it is believed that these thick low rank coals are the most prospective for the production of coal seam gas (CSG), otherwise known as coalbed methane (CBM), in Indonesia. As part of a major CSG exploration project, gas exploration drilling operations are being undertaken in Rambutan Gasfields in the Muaraenim Formation to characterize the CSG potential of the coals. The first stage of the project, which is described here, was designed to examine the gas reservoir properties with a focus on coal gas storage capacity and compositional properties. Some five CSG exploration boreholes were drilled in the Rambutan Gasfield, south of Palembang. The exploration boreholes were drilled to depths of {proportional_to} 1000 m into the Muaraenim Formation. Five major coal seams were intersected by these holes between the depths of 450 and 1000 m. The petrography of coal samples collected from these seams showed that they are vitrinite rich, with vitrinite contents of more than 75% (on a mineral and moisture free basis). Gas contents of up to 5.8 m{sup 3}/t were measured for the coal samples. The gas desorbed from coal samples contain mainly methane (CH{sub 4}) ranging from 80 to 93% and carbon dioxide (CO{sub 2}) ranging from 6 to 19%. The composition of the gas released into the production borehole/well is, however, much richer in CH{sub 4} with about 94 to 98% CH{sub 4} and less than 5% CO{sub 2}. The initial results of drilling and reservoir characterization studies indicate suitable gas recovery parameters for three of the five coal seams with a total thickness of more than 30 m. (author)

  19. July 2011 Memorandum: Improving EPA Review of Appalachian Surface Coal Mining Operations Under the Clean Water Act, National Environmental Policy Act, and the Environmental Justice Executive Order

    Science.gov (United States)

    Memorandum: Improving EPA Review of Appalachian Surface Coal Mining Operations Under the Clean Water Act, National Environmental Policy Act, and the Environmental Justice Executive Order, July 21, 2011

  20. Study on the influence of electromagnetic field on the property of coal combustion burnout in circulating fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Y. [Ruiping Coal and Electric Power Ltd. Co., Ruzhou (China)

    2008-08-15

    To study the influences of electromagnetism field pretreatment of pulverized Coal (EFPPC) on the properties of its combustion, thermogravimetric analysis, a Muffle furnace experiment and an X-ray diffraction experiment were carried out for three Coal banks. It was shown that EFPPC will induce the molecular structure of Coal to change into amorphous carbon, which causes an increase in the rate of oxygen absorption during the initial stages of Coal burning and reaction activity. It is also shown that the residual carbon of bituminous Coal would be increased by about 0.33% - 0.41%, i.e, the loss of standard Coal is about 3,000 t/a for double 480 t/h boilers, when applying EFPPC for 1 min at a temperature of 800 - 1,000 {sup o}C. When the temperature increases 200 {sup o}C, the residual carbon increases by about 2.07% but the effect of EFPPC is less than 0.21% for bituminous Coal and residual carbon is about 1.47% and the effect of EFPPC is less than 0.05% for lean Coal. Therefore the effect of increasing the temperature of EFPPC on residual carbon is less than that of increasing the time of EFPPC. 9 refs., 4 figs., 2 tabs.

  1. Effects of Design/Operating Parameters and Physical Properties on Slag Thickness and Heat Transfer during Coal Gasification

    Directory of Open Access Journals (Sweden)

    Insoo Ye

    2015-04-01

    Full Text Available The behaviors of the slag layers formed by the deposition of molten ash onto the wall are important for the operation of entrained coal gasifiers. In this study, the effects of design/operation parameters and slag properties on the slag behaviors were assessed in a commercial coal gasifier using numerical modeling. The parameters influenced the slag behaviors through mechanisms interrelated to the heat transfer, temperature, velocity, and viscosity of the slag layers. The velocity profile of the liquid slag was less sensitive to the variations in the parameters. Therefore, the change in the liquid slag thickness was typically smaller than that of the solid slag. The gas temperature was the most influential factor, because of its dominant effect on the radiative heat transfer to the slag layer. The solid slag thickness exponentially increased with higher gas temperatures. The influence of the ash deposition rate was diminished by the high-velocity region developed near the liquid slag surface. The slag viscosity significantly influenced the solid slag thickness through the corresponding changes in the critical temperature and the temperature gradient (heat flux. For the bottom cone of the gasifier, steeper angles were favorable in reducing the thickness of the slag layers.

  2. Intervention strategies to eliminate truck-related fatalities in surface coal mining in West Virginia.

    Science.gov (United States)

    Zhang, Meng; Kecojevic, Vladislav

    2016-01-01

    The main objective of this review was to build upon a previous study on the root causes of truck-related fatalities in surface coal mining operations in West Virginia, and to develop intervention strategies to eliminate these fatalities. This review considers a two-pronged approach to accident prevention: one that is fundamental and traditional (safety regulations, training and education, and engineering of the work environment); and one that is innovative and creative (e.g., applying technological advances to better control and eliminate the root causes of accidents). Suggestions for improving current training and education system are proposed, and recommendations are provided on improving the safety of mine working conditions, specifically safety conditions on haul roads, dump sites, and loading areas. We also discuss various currently available technologies that can help prevent haul truck-related fatal accidents. The results of this review should be used by mine personnel to help create safer working conditions and decrease truck-related fatalities in surface coal mining.

  3. Excimer laser surface modification: Process and properties

    Energy Technology Data Exchange (ETDEWEB)

    Jervis, T.R.; Nastasi, M. [Los Alamos National Lab., NM (United States); Hirvonen, J.P. [Technical Research Institute, Espoo (Finland). Metallurgy Lab.

    1992-12-01

    Surface modification can improve materials for structural, tribological, and corrosion applications. Excimer laser light has been shown to provide a rapid means of modifying surfaces through heat treating, surface zone refining, and mixing. Laser pulses at modest power levels can easily melt the surfaces of many materials. Mixing within the molten layer or with the gas ambient may occur, if thermodynamically allowed, followed by rapid solidification. The high temperatures allow the system to overcome kinetic barriers found in some ion mixing experiments. Alternatively, surface zone refinement may result from repeated melting-solidification cycles. Ultraviolet laser light couples energy efficiently to the surface of metallic and ceramic materials. The nature of the modification that follows depends on the properties of the surface and substrate materials. Alloying from both gas and predeposited layer sources has been observed in metals, semiconductors, and ceramics as has surface enrichment of Cr by zone refinement of stainless steel. Rapid solidification after melting often results in the formation of nonequilibrium phases, including amorphous materials. Improved surface properties, including tribology and corrosion resistance, are observed in these materials.

  4. Apparatus and method for direct measurement of coal ash sintering and fusion properties at elevated temperatures and pressures

    Science.gov (United States)

    Khan, M. Rashid

    1990-01-01

    A high-pressure microdilatometer is provided for measuring the sintering and fusion properties of various coal ashes under the influence of elevated pressures and temperatures in various atmospheres. Electrical resistivity measurements across a sample of coal ash provide a measurement of the onset of the sintering and fusion of the ash particulates while the contraction of the sample during sintering is measured with a linear variable displacement transducer for detecting the initiation of sintering. These measurements of sintering in coal ash at different pressures provide a mechanism by which deleterious problems due to the sintering and fusion of ash in various combustion systems can be minimized or obviated.

  5. Combustion properties, water absorption and grindability of raw/torrefied biomass pellets and Silantek coal

    Science.gov (United States)

    Matali, Sharmeela; Rahman, Norazah Abdul; Idris, Siti Shawaliah; Yaacob, Nurhafizah

    2017-12-01

    Torrefaction, also known as mild pyrolysis, is proven to convert raw biomass into a value-added energy commodity particularly for application in combustion and co-firing systems with improved storage and handling properties. This paper aims to compare the characteristics of Malaysian bituminous coal i.e. Silantek coal with raw and torrefied biomass pellet originated from oil palm frond and fast growing tree species, Leucaena Leucocephala. Biomass samples were initially torrefied at 300 °C for 60 minutes. Resulting torrefied biomass pellets were analysed using a number of standard fuel characterisation analyses i.e. elemental analysis, proximate analysis and calorific content (high heating values) experiments. Investigations on combustion characteristics via dynamic thermogravimetric analysis (TGA), grindability and moisture uptake tests were also performed on the torrefied biomass pellets. Better quality bio-chars were produced as compared to its raw forms and with optimal process conditions, torrefaction may potentially produces a solid fuel with combustion reactivity and porosity equivalent to raw biomass while having compatible energy density and grindability to coal.

  6. Study on Roadheader Cutting Load at Different Properties of Coal and Rock

    Directory of Open Access Journals (Sweden)

    Xueyi Li

    2013-01-01

    Full Text Available The mechanism of cutting process of roadheader with cutting head was researched, and the influences of properties of coal and rock on cutting load were deeply analyzed. Aimed at the defects of traditional calculation method of cutting load on fully expressing the complex cutting process of cutting head, the method of finite element simulation was proposed to simulate the dynamic cutting process. Aimed at the characteristics of coal and rock which affect the cutting load, several simulations with different firmness coefficient were taken repeatedly, and the relationship between three-axis force and firmness coefficient was derived. A comparative analysis of cutting pick load between simulation results and theoretical formula was carried out, and a consistency was achieved. Then cutting process with a total cutting head was carried out on this basis. The results show that the simulation analysis not only provides a reliable guarantee for the accurate calculation of the cutting head load and improves the efficiency of the cutting head cutting test but also offers a basis for selection of cutting head with different geological conditions of coal or rock.

  7. Regional scale selenium loading associated with surface coal mining, Elk Valley, British Columbia, Canada.

    Science.gov (United States)

    Wellen, Christopher C; Shatilla, Nadine J; Carey, Sean K

    2015-11-01

    Selenium (Se) concentrations in surface water downstream of surface mining operations have been reported at levels in excess of water quality guidelines for the protection of wildlife. Previous research in surface mining environments has focused on downstream water quality impacts, yet little is known about the fundamental controls on Se loading. This study investigated the relationship between mining practices, stream flows and Se concentrations using a SPAtially Referenced Regression On Watershed attributes (SPARROW) model. This work is part of a R&D program examining the influence of surface coal mining on hydrological and water quality responses in the Elk Valley, British Columbia, Canada, aimed at informing effective management responses. Results indicate that waste rock volume, a product of mining activity, accounted for roughly 80% of the Se load from the Elk Valley, while background sources accounted for roughly 13%. Wet years were characterized by more than twice the Se load of dry years. A number of variables regarding placement of waste rock within the catchments, length of buried streams, and the construction of rock drains did not significantly influence the Se load. The age of the waste rock, the proportion of waste rock surface reclaimed, and the ratio of waste rock pile side area to top area all varied inversely with the Se load from watersheds containing waste rock. These results suggest operational practices that are likely to reduce the release of Se to surface waters. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Thermal coal utilization for the ESCAP region

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    A selection of papers is presented originating from talks to coal utilization workshops for the ASEAN region in 1981. The papers cover: planning aspects - economic and technical aspects of coal usage, long term planning for fuel coal needs, planning and coal selection for coal-fired power plants, coal availability and marketing, and economic aspects of coal usage in developing countries; combustion and plant - changing from coal to oil, principles and problems of coal combustion, use of indigenous and imported coals and their effects on plant design, coal pulverizing mills, ash and dust disposal, environmental aspects of coal combustion, industrial sized coal-fired boilers; transport and storage -ocean shipment, coal receival facilities and associated operations, shipping and rail transport, coal handling and transport, environmental issue in the transport and handling of coal, coal preparation and blending; testing and properties - coal types, characterization properties and classification; training power plant operators; the cement industry and coal, the Australian black coal industry.

  9. Rapid comparison of properties on protein surface.

    Science.gov (United States)

    Sael, Lee; La, David; Li, Bin; Rustamov, Raif; Kihara, Daisuke

    2008-10-01

    The mapping of physicochemical characteristics onto the surface of a protein provides crucial insights into its function and evolution. This information can be further used in the characterization and identification of similarities within protein surface regions. We propose a novel method which quantitatively compares global and local properties on the protein surface. We have tested the method on comparison of electrostatic potentials and hydrophobicity. The method is based on 3D Zernike descriptors, which provides a compact representation of a given property defined on a protein surface. Compactness and rotational invariance of this descriptor enable fast comparison suitable for database searches. The usefulness of this method is exemplified by studying several protein families including globins, thermophilic and mesophilic proteins, and active sites of TIM beta/alpha barrel proteins. In all the cases studied, the descriptor is able to cluster proteins into functionally relevant groups. The proposed approach can also be easily extended to other surface properties. This protein surface-based approach will add a new way of viewing and comparing proteins to conventional methods, which compare proteins in terms of their primary sequence or tertiary structure.

  10. Surface Properties of TNOs: Preliminary Statistical Analysis

    Science.gov (United States)

    Antonieta Barucci, Maria; Fornasier, S.; Alvarez-Cantal, A.; de Bergh, C.; Merlin, F.; DeMeo, F.; Dumas, C.

    2009-09-01

    An overview of the surface properties based on the last results obtained during the Large Program performed at ESO-VLT (2007-2008) will be presented. Simultaneous high quality visible and near-infrared spectroscopy and photometry have been carried out on 40 objects with various dynamical properties, using FORS1 (V), ISAAC (J) and SINFONI (H+K bands) mounted respectively at UT2, UT1 and UT4 VLT-ESO telescopes (Cerro Paranal, Chile). For spectroscopy we computed the spectral slope for each object and searched for possible rotational inhomogeneities. A few objects show features in their visible spectra such as Eris, whose spectral bands are displaced with respect to pure methane-ice. We identify new faint absorption features on 10199 Chariklo and 42355 Typhon, possibly due to the presence of aqueous altered materials. The H+K band spectroscopy was performed with the new instrument SINFONI which is a 3D integral field spectrometer. While some objects show no diagnostic spectral bands, others reveal surface deposits of ices of H2O, CH3OH, CH4, and N2. To investigate the surface properties of these bodies, a radiative transfer model has been applied to interpret the entire 0.4-2.4 micron spectral region. The diversity of the spectra suggests that these objects represent a substantial range of bulk compositions. These different surface compositions can be diagnostic of original compositional diversity, interior source and/or different evolution with different physical processes affecting the surfaces. A statistical analysis is in progress to investigate the correlation of the TNOs’ surface properties with size and dynamical properties.

  11. Response of surface springs to longwall coal mining Wasatch Plateau, Utah

    International Nuclear Information System (INIS)

    Kadnuck, L.L.M.

    1994-01-01

    High-extraction longwall coal mining creates zones in the overburden where strata bend, fracture, or cave into the mine void. These physical alterations to the overburden stratigraphy have associated effects on the hydrologic regime. The US Bureau of Mines (SBM) studied impacts to the local hydrologic system caused by longwall mining in the Wasatch Plateau, Utah. Surface springs in the vicinity of two coal mines were evaluated for alterations in flow characteristics as mining progressed. Fourteen springs located above the mines were included in the study. Eight of the springs were located over longwall panels, four were located over barrier pillars and mains, and two ere located outside the area disturbed by mining. Flow hydrographs for each spring were compared to climatic data and time of undermining to assess if mining in the vicinity had influenced flow. Heights of fracturing and caving in the overburden resulting from seam extraction were calculated using common subsidence formulas, and used in conjunction with elevations of springs to assess if fracturing influenced the water-bearing zones studied. One spring over a panel exhibited a departure from a normally-shaped hydrograph after being undermined. Springs located over other mine structures, or outside the mine area did not show discernible effects from mining. The limited response of the springs was attributed to site-specific conditions that buffered mining impacts including the elevation of the springs above the mine level, and presence of massive sandstones and swelling clays in the overburden materials

  12. Hydrology and geochemistry of a surface coal mine in northwestern Colorado

    Science.gov (United States)

    Williams, R.S.; Clark, G.M.

    1994-01-01

    The hydrology and geochemistry of a reclaimed coal mine in northwestern Colorado were monitored during water years 1988 and 1989. Some data also were collected in water years 1987 and 1990. This report describes (1) the sources of hydrologic recharge to and discharge from reclaimed spoil, (2) the relative contributions of recharge to the reclaimed spoil aquifer from identified source waters and the rate of water movement from those sources to the reclaimed spoil, and (3) the geochemical reactions that control water quality in reclaimed spoil. The study area was at a dip-slope coal mine encompassing about 7 square miles with land slopes of varying aspect. The area was instrumented and monitored at five sites; two sites had unmined and reclaimed- spoil areas adjacent to each other and three sites were unmined. The mined areas had been reclaimed. Instrumentation at the study sites included 1 climate station, 3 rain gages, 19 soil-water access tubes, 2 lysimeters, 18 wells completed in bedrock, 7 wells completed in reclaimed spoil, and 2 surface- water gaging stations. The results of the study indicate that the reclaimed spoil is recharged from surface recharge and underburden aquifers. Discharge, as measured by lysimeters, was about 3 inches per year and occurred during and after snowmelt. Hydraulic-head measurements indicated a potential for ground-water movement from deeper to shallower aquifers. Water levels rose in the reclaimed-spoil aquifer and spring discharge at the toe of the spoil slopes increased rapidly in response to snowmelt. Water chemistry, stable isotopes, geochemical models, and mass-balance calculations indicate that surface recharge and the underburden aquifers each contribute about 50 percent of the water to the reclaimed-spoil aquifers. Geochemical information indicates that pyrite oxidation and dissolution of carbonate and efflorescent sulfate minerals control the water chemistry of the reclaimed-spoil aquifer.

  13. On-Site Radon Detection of Mining-induced Fractures from Overlying Strata to the Surface: A Case Study of the Baoshan Coal Mine in China

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2014-12-01

    Full Text Available Large-scale longwall mining of shallow coal seams may cause mining-induced fractures that can project completely through to the surface. This could lead to a series of mine safety and environmental issues, further deteriorating the already fragile ecological environment in the Western mining areas in China. Therefore, an accurate and effective understanding of the spatiotemporal evolution law of mining-induced fractures in overlying strata and its relationship to upper aquifers is critical. In this paper, the application of the geophysical-chemical properties of radon in mining engineering is explored as a potential solution to the shortcomings of existing surveying methods. A radioactive measurement method is proposed for the detection of the development of mining-induced fractures from overlying strata to the surface in the Baoshan Coal Mine (BCM. The on-site test indicated that the first weighting step is approximately 60 m, the average periodic weighting step is approximately 20 m, and the influence coverage of the advanced abutment pressure is approximately 30 m. The presented method could be used as an indirect technical support to increase the safety of coal mining by acting as a simple, fast, and reliable method of detecting mining-induced fractures in overlying strata.

  14. Surface coal mine land reclamation using a dry flue gas desulfurization product: Short-term and long-term water responses.

    Science.gov (United States)

    Chen, Liming; Stehouwer, Richard; Tong, Xiaogang; Kost, Dave; Bigham, Jerry M; Dick, Warren A

    2015-09-01

    Abandoned coal-mined lands are a worldwide concern due to their potential negative environmental impacts, including erosion and development of acid mine drainage. A field study investigated the use of a dry flue gas desulfurization product for reclamation of abandoned coal mined land in USA. Treatments included flue gas desulfurization product at a rate of 280 Mg ha(-1) (FGD), FGD at the same rate plus 112 Mg ha(-1) yard waste compost (FGD/C), and conventional reclamation that included 20 cm of re-soil material plus 157 Mg ha(-1) of agricultural limestone (SOIL). A grass-legume sward was planted after treatment applications. Chemical properties of surface runoff and tile water (collected from a depth of 1.2m below the ground surface) were measured over both short-term (1-4 yr) and long-term (14-20 yr) periods following reclamation. The pH of surface runoff water was increased from approximately 3, and then sustained at 7 or higher by all treatments for up to 20 yr, and the pH of tile flow water was also increased and sustained above 5 for 20 yr. Compared with SOIL, concentrations of Ca, S and B in surface runoff and tile flow water were generally increased by the treatments with FGD product in both short- and long-term measurements and concentrations of the trace elements were generally not statistically increased in surface runoff and tile flow water over the 20-yr period. However, concentrations of As, Ba, Cr and Hg were occasionally elevated. These results suggest the use of FGD product for remediating acidic surface coal mined sites can provide effective, long-term reclamation. Copyright © 2015. Published by Elsevier Ltd.

  15. Application of the surface reflection seismic method to shallow coal exploration in the plains of Alberta

    Energy Technology Data Exchange (ETDEWEB)

    Lyatsky, H.V.; Lawton, D.C. (University of Victoria, Victoria, BC (Canada). Dept. of Physics and Astronomy)

    1988-12-01

    A study was done to make a quantitative interpretation of reflection seismic data from the Highvale-Whitewood shallow coal deposit in central Alberta. Results showed that the data is useful in demonstrating coal thickness and stratigraphy as well as structural formation. Reflection character is affected by nature of the strata surrounding the coal deposit. 22 refs., 1 tab., 23 figs.

  16. Surface modification, microstructure and mechanical properties of investment cast superalloy

    OpenAIRE

    M. Zielińska; K. Kubiak; J. Sieniawski

    2009-01-01

    Purpose: The aim of this work is to determine physical and chemical properties of cobalt aluminate (CoAl2O4) modifiers produced by different companies and the influence of different types of modifiers on the grain size, the microstructure and mechanical properties of high temperature creep resisting superalloy René 77.Design/methodology/approach: The first stage of the research work took over the investigations of physical and chemical properties of cobalt aluminate manufactured by three diff...

  17. General programme of energy research: innovation in hard coal, 1974-1977. Preparation and surface facilities. Rahmenprogramm Energieforschung: Innovation Steinkohle, 1974-1977. Aufbereitung und Tagesanlagen)

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    Under the program Preparation and Surface Facilities initiated by the Federal Ministry of Economy of the FRG financial support in the amount of 50% (approx. 17 million DM) of the total project costs was allocated to eight applicants from the mining industry. The Ministry subsidized 15 research projects in the field of coal preparation and handling dealing with: surface blending and storage facilities; the development of a solid bowl centrifuge, steam cowl filter, and reciprocating centrifuge for dewatering coal fines; development of a jig and a screen sizer for coal sizing; clarification units and combustion of waste slurries in a fluidized-bed furnace; computerized monitoring of coal flow in surface and underground installations; the development of a conception for preparing coal otherwise difficult to prepare; and the development of the Olifloc method for agglomeration of coal fines sludge and separation from tailings. (In German)

  18. Surface properties of functional polymer systems

    Science.gov (United States)

    Wong, Derek

    Polymer surface modification typically involves blending with other polymers or chemical modification of the parent polymer. Such strategies inevitably result in polymer systems that are spatially and chemically heterogeneous, and which exhibit the phenomenon of surface segregation. This work investigates the effects of chain architecture on the surface segregation behavior of such functionally modified polymers using a series of end- and center-fluorinated poly(D,L-lactide). Surface segregation of the fluorinated functional groups was observed in both chain architectures via AMPS and water contact angle. Higher surface segregation was noted for functional groups located at the chain end as opposed to those in the middle of the chain. A self-consistent mean-field lattice theory was used to model the composition depth profiles of functional groups and excellent agreement was found between the model predictions and the experimental AMPS data in both chain architectures. Polymer properties are also in general dependent on both time and temperature, and exhibit a range of relaxation times in response to environmental stimuli. This behavior arises from the characteristic frequencies of molecular motions of the polymer chain and the interrelationship between time and temperature has been widely established for polymer bulk properties. There is evidence that surface properties also respond in a manner that is time and temperature dependent and that this dependence may not be the same as that observed for bulk properties. AMPS and water contact angle experiments were used to investigate the surface reorganization behavior of functional groups using a series of anionically synthesized end-fluorinated and end-carboxylated poly(styrene). It was found that both types of functional end-groups reorganized upon a change in the polarity of the surface environment in order to minimize the surface free energy. ADXPS and contact angle results suggest that the reorganization depth was

  19. Effects of coal mining on ground and surface water quality, Monongalia County, West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Corbett, R G

    1977-07-01

    Water quality data are compared. Areas disturbed extensively either by surface or underground mining for bituminous coal in Monongalia County, West Virginia yield water of poorer quality than similar terrain which is not so disturbed. Specifically, the disturbed areas yield hard water of the calcium-sulfate or calcium-magnesium-sulfate type which is low in pH, high in iron and aluminum, and which contains trace elements one or more orders of magnitude greater than water from undisturbed terrain. These hard waters differ from the more common type of hard waters in that sulfate rather than bicarbonate is the dominant anion. As such they may provide further insight into factors affecting the relationship between water hardness and cardiovascular disease rates. The necessary additional data are being collected.

  20. The effect of coal surface mine reclamation on lepidopteran populations in Virginia

    International Nuclear Information System (INIS)

    Holl, K.D.; Cairns, J. Jr.

    1993-01-01

    The goals of this research are to determine whether lepidopteran communities of reclaimed coal surface mines approximate those of the surrounding, unmined hardwood forests and which habitat variables are influencing lepidopteran communities on these sites. Surveys of 19 reclaimed and hardwood sites during the 1992 field season indicate that the lepidopteran fauna of reclaimed sites does not resemble that of the surrounding hardwoods. While plant species richness is not significantly correlated with lepidopteran species richness, multivariate analysis suggests that vegetative community composition has a strong influence on lepidopteran community composition. Nectar abundance is important in explaining butterfly species richness. While the number of species in reclaimed sites is similar to the number in the surrounding hardwoods, reclaimed sites tend to host widespread, r-selected species, which raises questions on the value of reclaimed sites in conserving less common

  1. Treatment of sulphated water of surface origin produced by an open pit coal mine

    Directory of Open Access Journals (Sweden)

    Alan Campos-Sánchez

    2016-12-01

    Full Text Available The purpose of this study was to select the most suitable method of treatment of sulfated water produced by an open pit coal mine in Venezuela. Samples of water taken on surface, middle and bottom of water bodies in three areas were subjected to basic, gravimetric, volumetric and colorimetric analysis. The results indicated that the pH is within limits permitted by current environmental regulations, while total suspended solids, total dissolved solids, and sulfates exceed the normed values. The aerobic wetland method was selected as the most efficient for the removal of sulfates, depending on the physicochemical characteristics of the sulphated waters from the mine and because they are systems that use natural energy to purify water, its construction and maintenance costs Is significantly inferior to the conventional treatments and because, being replicas of natural ecosystems, they are integrated to the environment.

  2. Surface active properties of lipid nanocapsules.

    Directory of Open Access Journals (Sweden)

    Celia R A Mouzouvi

    Full Text Available Lipid nanocapsules (LNCs are biomimetic nanocarriers used for the encapsulation of a broad variety of active ingredients. Similar to surface active compounds, LNCs contain both hydrophilic and hydrophobic parts in their structure. Moreover, the components of LNCs, macrogol 15 hydroxystearate (MHS and lecithin, are known for their surface active properties. Therefore, the aim of this paper was to investigate the capability of the LNCs to decrease surface tension using two techniques: drop tensiometry and the Wilhelmy plate method. LNCs with diameters ranging from 30 to 100 nm were successfully obtained using a phase inversion technique. The LNCs' properties, such as size and zeta potential, depend on the composition. LNCs exhibit a lower limiting surface tension compared to MHS (34.8-35.0 mN/m and 37.7-38.8 mN/m, respectively, as confirmed by both drop tensiometry and the Wilhelmy plate method. LNCs have exhibited a saturated interfacial concentration (SIC that was 10-fold higher than the critical micellar concentration (CMC of MHS or the SIC of binary and ternary mixtures of LNC ingredients. The SIC of the LNC formulations depended on the mass mixing ratio of the MHS/triglycerides but not on the presence of lecithin. The CMC/SIC values measured by the Wilhelmy plate method were higher than those obtained using drop tensiometry because of the longer duration of the tensiometry measurement. In conclusion, the surfactant-like properties of the LNCs offer new possibilities for medical and pharmaceutical applications.

  3. Weathering behaviour of overburden-coal ash blending in relation to overburden management for acid mine drainage prevention in coal surface mine

    International Nuclear Information System (INIS)

    Gautama, R.S.; Kusuma, G.J.; Lestari, I.; Anggana, R.P.

    2010-01-01

    Potentially acid forming (PAF) materials are encapsulated with non-acid forming materials (NAF) in order to prevent acid mine drainage (AMD) in surface coal mines. NAF compaction techniques with fly and bottom ashes from coal-fired power plants are used in mines with limited amounts of NAF materials. This study investigated the weathering behaviour of blended overburden and coal combustion ash in laboratory conditions. Free draining column leach tests were conducted on different blending schemes. The weathering process was simulated by spraying the samples with de-ionized water once per day. The leachates were then analyzed using X-ray diffraction and fluorescence analyses in order to identify the mineral composition of the samples over a 14 week period. Results of the study indicated that the weathering process plays a significant role in controlling infiltration rates, and may increase the capability of capping materials to prevent infiltration into PAF materials. Fly- and bottom-ash additions improved the performance of the encapsulation materials. 3 refs., 4 tabs., 2 figs.

  4. 75 FR 18500 - Guidance on Improving EPA Review of Appalachian Surface Coal Mining Operations under the Clean...

    Science.gov (United States)

    2010-04-12

    ..., Monday through Friday, excluding legal holidays. The telephone number for the Public Reading Room is (202... recognizes the importance of this guidance to its Federal and state partners, to the regulated community, and... of Appalachian Surface Coal Mining Operations under the Clean Water Act, National Environmental...

  5. 30 CFR 785.19 - Surface coal mining and reclamation operations on areas or adjacent to areas including alluvial...

    Science.gov (United States)

    2010-07-01

    ... alluvial valley floor exists if it finds that— (i) Unconsolidated streamlaid deposits holding streams are... on areas or adjacent to areas including alluvial valley floors in the arid and semiarid areas west of....19 Surface coal mining and reclamation operations on areas or adjacent to areas including alluvial...

  6. Determination of properties of clean coal technology post-process residue

    Directory of Open Access Journals (Sweden)

    Agnieszka Klupa

    2016-01-01

    Full Text Available This article presents the possibilities of using modern measuring devices to determine the properties of process residues (Polish acronym: UPP. UPP was taken from the combustion process from a power plant in Silesia. Determining the properties of UPP is the basis for making decisions about its practical application, for example, as a raw material to obtain useful products such as: pozzolan, cenosphere or zeolite, for which there is demand. The development of advanced technology and science has given rise to modern and precise research tools that contribute to the development of appropriate methods to assess the properties of post-process residue. For this study the following were used: scanning electron microscope with EDS microanalysis and an analyzer for particle size-, shape- and number- analysis. The study conducted confirms the effectiveness of SEM analysis to determine the properties of post-process residue from Clean Coal Technologies (CCT. The results obtained are an introduction to further research on the determination of properties of CCT post-process residue. Research to determine the properties of CCT post-process residue only began relatively recently.

  7. Measurement and investigation of effects of coal tar pitch fractions in nuclear graphite properties

    International Nuclear Information System (INIS)

    Fatemi, K.; Fatoorehchian, S.; Ahari Hashemi, F.; Ahmadi, Sh.

    2003-01-01

    Coal tar pitch has a complex chemical structure. Determination of α, β, γ fractions, is one of the methods to get information about its properties. In graphite fabrication it plays a role as a binder for coke particles. During the thermal treatment it carbonizes and changes to a secondary coke. This has considerable affects on the graphite properties. In this paper, determination of α, β, γ-1 fraction in three different types of pitches have been carried out. Graphite specimens have been fabricated by using these pitches and anisotropy coke in laboratory scale. The graphite properties have been compared with the nuclear graphite prototype. The comparison of the results showed that the density and compression strength are appreciable while the anisotropy factor of properties is about one. The linear thermal expansion in graphite from Iranian pitch had a better, result, where it stands in the nuclear range of usage. As a result, our studies showed that the graphite properties are affected by properties of pitch fractions, where it can be used as a proper sample for the graphite fabrication

  8. A summary of fish and wildlife information needs to surface mine coal in the United States. Part 3. A handbook for meeting fish and wildlife information needs to surface mine coal: OSM Region III. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hinkle, C.R.; Ambrose, R.E.; Wenzel, C.R.

    1981-02-01

    The report contains information to assist in protecting, enhancing, and reducing impacts to fish and wildlife resources during surface mining of coal. It gives information on the premining, mining, reclamation and compliance phases of surface mining. Methods and sources to obtain information to satisfy state and Federal regulations are presented. Considerable emphasis is placed on postmining assistance. This volume is specifically for the states of Minnesota, Wisconsin, Michigan, Illinois, Indiana and Ohio.

  9. Summary of fish and wildlife information needs to surface mine coal in the United States. Part 3. A handbook for meeting fish and wildlife information needs to surface mine coal: OSM Region IV. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hinkle, C.R.; Ambrose, R.E.; Wenzel, C.R.

    1981-02-01

    The report contains information to assist in protecting, enhancing, and reducing impacts to fish and wildlife resources during surface mining of coal. It gives information on the premining, mining, reclamation and compliance phases of surface mining. Methods and sources to obtain information to satisfy state and Federal regulations are presented. This volume is specifically for the states of Nebraska, Iowa, Kansas, Missouri, Oklahoma, Arkansas, Texas and Louisiana.

  10. Summary of fish and wildlife information needs to surface mine coal in the United States. Part 3. A handbook for meeting fish and wildlife information needs to surface mine coal: OSM Region I. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hinkle, C.R.; Ambrose, R.E.; Wenzel, C.R.

    1981-02-01

    The report contains information to assist in protecting, enhancing, and reducing impacts to fish and wildlife resources during surface mining of coal. It gives information on the premining, mining, reclamation and compliance phases of surface mining. Methods and sources to obtain information to satisfy state and Federal regulations are presented. This volume is specifically for the states of Maine, Vermont, New Hampshire, Massachusetts, Connecticut, New York, Rhode Island, Pennsylvania, New Jersey, Delaware, Maryland, West Virginia and Virginia.

  11. Summary of fish and wildlife information needs to surface mine coal in the United States. Part 3. A handbook for meeting fish and wildlife information needs to surface mine coal: OSM Region II. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hinkle, C.R.; Ambrose, R.E.; Wenzel, C.R.

    1981-02-01

    The report contains information to assist in protecting, enhancing, and reducing impacts to fish and wildlife resources during surface mining of coal. It gives information on the premining, mining, reclamation and compliance phases of surface mining. Methods and sources to obtain information to satisfy state and Federal regulations are presented. This volume is specifically for the states of Kentucky, Tennessee, North Carolina, South Carolina, Georgia, Alabama, Mississippi and Florida.

  12. Characterizing the statistical properties of protein surfaces

    Science.gov (United States)

    Bak, Ji Hyun; Bitbol, Anne-Florence; Bialek, William

    Proteins and their interactions form the body of the signaling transduction pathway in many living systems. In order to ensure the accuracy as well as the specificity of signaling, it is crucial that proteins recognize their correct interaction partners. How difficult, then, is it for a protein to discriminate its correct interaction partner(s) from the possibly large set of other proteins it may encounter in the cell? An important ingredient of recognition is shape complementarity. The ensemble of protein shapes should be constrained by the need for maintaining functional interactions while avoiding spurious ones. To address this aspect of protein recognition, we consider the ensemble of proteins in terms of the shapes of their surfaces. We take into account the high-resolution structures of E.coli non-DNA-binding cytoplasmic proteins, retrieved from the Protein Data Bank. We aim to characterize the statistical properties of the protein surfaces at two levels: First, we study the intrinsic dimensionality at the level of the ensemble of the surface objects. Second, at the level of the individual surfaces, we determine the scale of shape variation. We further discuss how the dimensionality of the shape space is linked to the statistical properties of individual protein surfaces. Jhb and WB acknowledge support from National Science Foundation Grants PHY-1305525 and PHY-1521553. AFB acknowledges support from the Human Frontier Science Program.

  13. Mechanical properties of ion implanted ceramic surfaces

    International Nuclear Information System (INIS)

    Burnett, P.J.

    1985-01-01

    This thesis investigates the mechanisms by which ion implantation can affect those surface mechanical properties of ceramics relevant to their tribological behaviour, specifically hardness and indentation fracture. A range of model materials (including single crystal Si, SiC, A1 2 0 3 , Mg0 and soda-lime-silica glass) have been implanted with a variety of ion species and at a range of ion energies. Significant changes have been found in both low-load microhardness and indentation fracture behaviour. The changes in hardness have been correlated with the evolution of an increasingly damaged and eventually amorphous thin surface layer together with the operation of radiation-, solid-solution- and precipitation-hardening mechanisms. Compressive surface stresses have been shown to be responsible for the observed changes in identation fracture behaviour. In addition, the levels of surface stress present have been correlated with the structure of the surface layer and a simple quantitative model proposed to explain the observed stress-relief upon amorphisation. Finally, the effects of ion implantation upon a range of polycrystalline ceramic materials has been investigated and the observed properties modifications compared and contrasted to those found for the model single crystal materials. (author)

  14. Welcome to Surface Topography: Metrology and Properties

    Science.gov (United States)

    Leach, Richard

    2013-11-01

    I am delighted to welcome readers to this inaugural issue of Surface Topography: Metrology and Properties (STMP). In these days of citation indexes and academic reviews, it is a tough, and maybe a brave, job to start a new journal. But the subject area has never been more active and we are seeing genuine breakthroughs in the use of surfaces to control functional performance. Most manufactured parts rely on some form of control of their surface characteristics. The surface is usually defined as that feature on a component or device, which interacts with either the environment in which it is housed (or in which the device operates), or with another surface. The surface topography and material characteristics of a part can affect how fluids interact with it, how the part looks and feels and how two bearing parts will slide together. The need to control, and hence measure, surface features is becoming increasingly important as we move into a miniaturized world. Surface features can become the dominant functional features of a part and may become large in comparison to the overall size of an object. Research into surface texture measurement and characterization has been carried out for over a century and is now more active than ever, especially as new areal surface texture specification standards begin to be introduced. The range of disciplines for which the function of a surface relates to its topography is very diverse; from metal sheet manufacturing to art restoration, from plastic electronics to forensics. Until now, there has been no obvious publishing venue to bring together all these applications with the underlying research and theory, or to unite those working in academia with engineering and industry. Hence the creation of Surface Topography: Metrology and Properties . STMP will publish the best work being done across this broad discipline in one journal, helping researchers to share common themes and highlighting and promoting the extraordinary benefits this

  15. Cadmium adsorption by coal combustion ashes-based sorbents-Relationship between sorbent properties and adsorption capacity

    Energy Technology Data Exchange (ETDEWEB)

    Balsamo, Marco; Di Natale, Francesco; Erto, Alessandro; Lancia, Amedeo [Dipartimento di Ingegneria Chimica, Universita degli Studi di Napoli Federico II, Piazzale Vincenzo Tecchio 80, 80125 Napoli (Italy); Montagnaro, Fabio, E-mail: fabio.montagnaro@unina.it [Dipartimento di Chimica, Universita degli Studi di Napoli Federico II, Complesso Universitario di Monte Sant' Angelo, 80126 Napoli (Italy); Santoro, Luciano [Dipartimento di Chimica, Universita degli Studi di Napoli Federico II, Complesso Universitario di Monte Sant' Angelo, 80126 Napoli (Italy)

    2011-03-15

    A very interesting possibility of coal combustion ashes reutilization is their use as adsorbent materials, that can also take advantage from proper beneficiation techniques. In this work, adsorption of cadmium from aqueous solutions was taken into consideration, with the emphasis on the intertwining among waste properties, beneficiation treatments, properties of the beneficiated materials and adsorption capacity. The characterization of three solid materials used as cadmium sorbents (as-received ash, ash sieved through a 25 {mu}m-size sieve and demineralized ash) was carried out by chemical analysis, infrared spectroscopy, laser granulometry and mercury porosimetry. Cadmium adsorption thermodynamic and kinetic tests were conducted at room temperature, and test solutions were analyzed by atomic absorption spectrophotometry. Maximum specific adsorption capacities resulted in the range 0.5-4.3 mg g{sup -1}. Different existing models were critically considered to find out an interpretation of the controlling mechanism for adsorption kinetics. In particular, it was observed that for lower surface coverage the adsorption rate is governed by a linear driving force while, once surface coverage becomes significant, mechanisms such as the intraparticle micropore diffusion may come into play. Moreover, it was shown that both external fluid-to-particle mass transfer and macropore diffusion hardly affect the adsorption process, which was instead regulated by intraparticle micropore diffusion: characteristic times for this process ranged from 4.1 to 6.1 d, and were fully consistent with the experimentally observed equilibrium times. Results were discussed in terms of the relationship among properties of beneficiated materials and cadmium adsorption capacity. Results shed light on interesting correlations among solid properties, cadmium capture rate and maximum cadmium uptake.

  16. Deformation properties of sedimentary rocks in the process of underground coal gasification

    Directory of Open Access Journals (Sweden)

    Mirosława Bukowska

    2015-01-01

    Full Text Available The article presents results of research into changes in deformation properties of rocks, under influence of temperature, during the process of underground coal gasification. Samples of carboniferous sedimentary rocks (claystones and sandstones, collected in different areas of Upper Silesian Coal Basin (GZW, were heated at the temperature of between 100 and 1000–1200 °C, and then subjected to uniaxial compression tests to obtain a full stress-strain curves of the samples and determine values of residual strain and Poisson's ratio. To compare the obtained values of deformation parameters of rocks, tested in dry-air state and after heating in a given range of temperature, normalised values of residual strain and Poisson's ratio were determined. Based on them, coefficient of influence of temperature on tested deformation parameters was determined. The obtained values of the coefficient can be applied in mining practice to forecast deformability of gangue during underground coal gasification, when in the direct surrounding of a georeactor there are claystones or sandstones. The obtained results were analysed based on classification of uniaxial compression strength of GZW gangue, which formed the basis for dividing claystones and sandstones into very low, low, medium and high uniaxial compression strength rocks. Based on the conducted tests it was concluded that the influence of uniaxial compression strength on the value of residual strain, unlike the influence of grain size of sandstones, is unambiguous within the range of changes in the parameter. Among claystones changes in the value of Poisson's ratio depending on their initial strength were observed. Sandstones of different grain size either increased or decreased the value of Poisson's ratio in comparison with the value determined at room temperature in dry-air conditions.

  17. Soil-characterization and soil-amendment use on coal surface mine lands: An annotated bibliography. Information Circular/1991

    International Nuclear Information System (INIS)

    Norland, M.R.; Veith, D.L.

    1991-01-01

    The U.S. Bureau of Mines Report on United States and Canadian Literature pertaining to soil characterization and the use of soil amendments as a part of the reclamation process of coal surface-mined lands contains 1,280 references. The references were published during the 1977 to 1988 period. Each reference is evaluated by keywords, providing the reader with a means of rapidly sorting through the references to locate those articles with the coal mining regions and subjects of interest. All references are annotated

  18. CO2 adsorption-assisted CH4 desorption on carbon models of coal surface: A DFT study

    Science.gov (United States)

    Xu, He; Chu, Wei; Huang, Xia; Sun, Wenjing; Jiang, Chengfa; Liu, Zhongqing

    2016-07-01

    Injection of CO2 into coal is known to improve the yields of coal-bed methane gas. However, the technology of CO2 injection-enhanced coal-bed methane (CO2-ECBM) recovery is still in its infancy with an unclear mechanism. Density functional theory (DFT) calculations were performed to elucidate the mechanism of CO2 adsorption-assisted CH4 desorption (AAD). To simulate coal surfaces, different six-ring aromatic clusters (2 × 2, 3 × 3, 4 × 4, 5 × 5, 6 × 6, and 7 × 7) were used as simplified graphene (Gr) carbon models. The adsorption and desorption of CH4 and/or CO2 on these carbon models were assessed. The results showed that a six-ring aromatic cluster model (4 × 4) can simulate the coal surface with limited approximation. The adsorption of CO2 onto these carbon models was more stable than that in the case of CH4. Further, the adsorption energies of single CH4 and CO2 in the more stable site were -15.58 and -18.16 kJ/mol, respectively. When two molecules (CO2 and CH4) interact with the surface, CO2 compels CH4 to adsorb onto the less stable site, with a resulting significant decrease in the adsorption energy of CH4 onto the surface of the carbon model with pre-adsorbed CO2. The Mulliken charges and electrostatic potentials of CH4 and CO2 adsorbed onto the surface of the carbon model were compared to determine their respective adsorption activities and changes. At the molecular level, our results showed that the adsorption of the injected CO2 promoted the desorption of CH4, the underlying mechanism of CO2-ECBM.

  19. Tribocharging in electrostatic beneficiation of coal: Effects of surface composition on work function as measured by x-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy in air

    International Nuclear Information System (INIS)

    Trigwell, S.; Mazumder, M.K.; Pellissier, R.

    2001-01-01

    The cleaning of coal by electrostatic beneficiation is based on tribocharging characteristics of pulverized coal particles with diameter smaller than 120 μm. The tribocharging process should be such that the organic coal particles must charge with a polarity opposite to that of the sulfur and the mineral containing particles so that coal can be separated from minerals by using a charge separator. However, the charge distribution of electrostatically separated coal particles indicates that coal exhibits bipolar charging. A significant fraction of the coal particles charges negatively which appears to be in conflict with expectations in that the organic coal particles should charge positively, and the mineral particles, present as impurities such as pyrite, charge negatively when tribocharged against copper. The relative work functions of the particles (coal and mineral) and that of the metal surface (copper or stainless steel) used for tribocharging predict these expected results. However, ultraviolet photoelectron spectroscopy (UPS) measurements in air on specimens of three different coal species, showed the work function to be approximately 5.4 eV, which is higher than a reported measured work function of 3.93 eV. Studies by UPS and x-ray photoelectron spectroscopy on copper, stainless steel, aluminum, and other commonly used tribocharging materials such as nylon and polytetrafluorethylene, as well as pure pyrite, showed that the work function varied considerably as a function of surface composition. Therefore, the reason for the bipolar charging of the coal particles may be the too small differences in work functions between coal powder and copper used as the charging material. The choice of a material for impaction triboelectric charging for coal or mineral separation should therefore depend upon the actual work function as modified by the ambient conditions such as moisture content and the oxidation of the surface

  20. Preparation and Properties of Asphalt Binders Modified by THFS Extracted From Direct Coal Liquefaction Residue

    Directory of Open Access Journals (Sweden)

    Jie Ji

    2017-11-01

    Full Text Available This paper aims to study the preparation and viscoelastic properties of asphalt binder modified by tetrahydrofuran soluble fraction (THFS extracted from direct coal liquefaction residue. The modified asphalt binders, which blended with SK-90 (control asphalt binder and 4%, 6%, 8% and 10% THFS (by weight of SK-90, were fabricated. The preparation process for asphalt binder was optimized in terms of the orthogonal array test strategy and gray correlation analysis results. The properties of asphalt binder were measured by applying Penetration performance grade and Superpave performance grade specifications. In addition, the temperature step and frequency sweep test in Dynamic Shear Rheometer were conducted to predict the rheological behavior, temperature and frequency susceptibility of asphalt binder. The test results suggested the optimal preparation process, such as 150 °C shearing temperature, 45 min shearing time and 4000 rpm shearing rate. Subsequently, the addition of THFS was beneficial in increasing the high-temperature properties but decreased the low-temperature properties and resistance to fatigue. The content analysis of THFS showed the percentage of 4~6% achieved a balance in the high-and-low temperature properties of asphalt binder. The asphalt binder with higher THFS content exhibited higher resistance to rutting and less sensitivity to frequency and temperature.

  1. Coal combustion waste management at landfills and surface impoundments 1994-2004.

    Energy Technology Data Exchange (ETDEWEB)

    Elcock, D.; Ranek, N. L.; Environmental Science Division

    2006-09-08

    On May 22, 2000, as required by Congress in its 1980 Amendments to the Resource Conservation and Recovery Act (RCRA), the U.S. Environmental Protection Agency (EPA) issued a Regulatory Determination on Wastes from the Combustion of Fossil Fuels. On the basis of information contained in its 1999 Report to Congress: Wastes from the Combustion of Fossil Fuels, the EPA concluded that coal combustion wastes (CCWs), also known as coal combustion by-products (CCBs), did not warrant regulation under Subtitle C of RCRA, and it retained the existing hazardous waste exemption for these materials under RCRA Section 3001(b)(3)(C). However, the EPA also determined that national regulations under Subtitle D of RCRA were warranted for CCWs that are disposed of in landfills or surface impoundments. The EPA made this determination in part on the basis of its findings that 'present disposal practices are such that, in 1995, these wastes were being managed in 40 percent to 70 percent of landfills and surface impoundments without reasonable controls in place, particularly in the area of groundwater monitoring; and while there have been substantive improvements in state regulatory programs, we have also identified gaps in State oversight' (EPA 2000). The 1999 Report to Congress (RTC), however, may not have reflected the changes in CCW disposal practices that occurred since the cutoff date (1995) of its database and subsequent developments. The U.S. Department of Energy (DOE) and the EPA discussed this issue and decided to conduct a joint DOE/EPA study to collect new information on the recent CCW management practices by the power industry. It was agreed that such information would provide a perspective on the chronological adoption of control measures in CCW units based on State regulations. A team of experts from the EPA, industry, and DOE (with support from Argonne National Laboratory) was established to develop a mutually acceptable approach for collecting and analyzing data

  2. Comparison of FeS, FeS + S and solid superacid catalytic properties for coal hydro-liquefaction

    Energy Technology Data Exchange (ETDEWEB)

    Zhicai Wang; Hengfu Shui; Dexiang Zhang; Jinsheng Gao [East China University of Science and Technology, Shanghai (China). College of Resource and Environment Engineering

    2007-03-15

    Catalyst plays an important role in direct coal liquefaction. This paper focuses on the catalytic behavior of a novel SO{sub 4}{sup 2-}/ZrO{sub 2} superacid catalyst in coal hydro-liquefaction. A series of hydro-liquefaction experiments were conducted under mild conditions - 400{sup o}C, 30 min and H{sub 2} initial pressure 4 MPa in a batch autoclave with a volume of 100 ml. The catalytic property of SO{sub 4}{sup 2-}/ZrO{sub 2} was compared with FeS and FeS + S by Shenhua coal. The liquefaction products catalyzed by different catalysts were analyzed by FTIR spectrum, {sup 1}H NMR spectrum and element analysis. In addition, the SO{sub 4}{sup 2-}/ZrO{sub 2} solid superacid was characterized. The results indicated that the SO{sub 4}{sup 2-}/ZrO{sub 2} solid superacid shows outstanding catalytic property for direct liquefaction of coal and gives the highest coal conversion and gas + oil yield compared to other two catalysts. The THF conversion and the extraction yield of CS{sub 2}/NMP mixed solvent of liquefied coal catalyzed with SO{sub 4}{sup 2-}/ZrO{sub 2} are 76.3%, daf and 81.2%, daf respectively, and the yield of gas + oil is 62.5%, daf under the condition used in this study. The pyrolysis of coal macromolecular clusters can be promoted by catalysts such as FeS, FeS + S and SO{sub 4}{sup 2-}/ZrO{sub 2}. There may be only the pyrolysis of volatile matter and the relaxation of the structure of coal macromolecular clusters in non-catalytic liquefaction at 400{sup o}C. Added sulfur in FeS can improve the catalytic activity of hydrogenation. SO{sub 4}{sup 2-}/ZrO{sub 2} is a notable catalyst in the study of coal direct liquefaction because it shows excellent catalytic activities for the pyrolysis and the hydrogenation. In addition, it has been found that the C-O bond is the most stable group in coal liquefaction reaction except for the covalent bond between carbon and carbon. 34 refs., 6 figs., 6 tabs.

  3. Quantifying topographic differences between premining and reclaimed landscapes at a large surface coal mine

    International Nuclear Information System (INIS)

    Friedlander, J.D.

    1994-01-01

    Premining and reclaimed landscapes on 2,300 acres were compared quantitatively at a surface coal mine in western North Dakota. Weighted average slopes were determined by calculating acres in each slope class (0% to 3%, 3% to 6%, 6% to 9%, 9% to 15%, and > 15%) and dividing by the total number of acres. Weighted average slopes were 3.8% and 3.0% for all premining and reclaimed lands respectively. Weighted average slopes were 2.7% and 2.1% for premining and reclaimed croplands respectively. Reclaimed native rangeland slopes are 5.5% compared to 7.0% premining. The acreage of native rangeland with >9% slopes decreased more than 50% during reclamation. For all mined lands there is 25% more reclaimed land with 0% to 3% slopes and 25% less reclaimed land with >6% slopes than before mining. Topographic changes caused by surface mining and reclamation enhance soil conservation, moisture retention, and agricultural productivity. A cross-sectional profile had 26.8 and 15.5 premining and reclaimed land up-down gradient changes per mile respectively, indicating reclaimed land is less diverse than it was prior to mining. Slope class map units average 3.5 and 4.4 acres respectively on premining and reclaimed lands, further indicating reduced diversity. Landscape improvements conflict with regulatory diversity requirements to determine reclamation success

  4. Coal mine subsidence

    International Nuclear Information System (INIS)

    Rahall, N.J.

    1991-05-01

    This paper examines the efficacy of the Department of the Interior's Office of Surface Mining Reclamation and Enforcement's (OSMRE) efforts to implement the federally assisted coal mine subsidence insurance program. Coal mine subsidence, a gradual settling of the earth's surface above an underground mine, can damage nearby land and property. To help protect property owners from subsidence-related damage, the Congress passed legislation in 1984 authorizing OSMRE to make grants of up to $3 million to each state to help the states establish self-sustaining, state-administered insurance programs. Of the 21 eligible states, six Colorado, Indiana, Kentucky, Ohio, West Virginia, and Wyoming applied for grants. This paper reviews the efforts of these six states to develop self-sustaining insurance programs and assessed OSMRE's oversight of those efforts

  5. Research into properties of dust from domestic central heating boiler fired with coal and solid biofuels

    Directory of Open Access Journals (Sweden)

    Konieczyński Jan

    2017-06-01

    Full Text Available The aim of this research was to assess the content and composition of the pollutants emitted by domestic central heating boilers equipped with an automatic underfeed fuel delivery system for the combustion chamber. The comparative research was conducted. It concerned fuel properties, flue gas parameters, contents of dust (fl y ash and gaseous substances polluting the air in the flue gases emitted from a domestic CH boiler burning bituminous coal, pellets from coniferous wood, cereal straw, miscanthus, and sunflower husks, coniferous tree bark, and oats and barley grain. The emission factors for dust and gaseous air pollutants were established as they are helpful to assess the contribution of such boilers in the atmospheric air pollution. When assessing the researched boiler, it was found out that despite the development in design and construction, flue gases contained fly ash with a significant EC content, which affected the air quality.

  6. Mineralogy and geochemistry of boehmite-rich coals: New insights from the Haerwusu Surface Mine, Jungar Coalfield, Inner Mongolia, China

    Science.gov (United States)

    Dai, S.; Li, D.; Chou, C.-L.; Zhao, L.; Zhang, Y.; Ren, D.; Ma, Y.; Sun, Y.

    2008-01-01

    Boehmite-rich coal of Pennsylvanian age was discovered earlier at the Heidaigou Surface Mine, Jungar Coalfield, Inner Mongolia, China. This paper reports new results on 29 bench samples of the no. 6 coal from a drill core from the adjacent Haerwusu Surface Mine, and provides new insights into the origin of the minerals and elements present. The results show that the proportion of inertinite in the no. 6 coal is higher than in other Late Paleozoic coals in northern China. Based on mineral proportions (boehmite to kaolinite ratio) and major element concentrations in the coal benches of the drill core, the no. 6 coal may be divided into five sections (I to V). Major minerals in Sections I and V are kaolinite. Sections II and IV are mainly kaolinite with a trace of boehmite, and Section III is high in boehmite. The boehmite is derived from bauxite in the weathered surface (Benxi Formation) in the sediment-source region. The no. 6 coal is rich in Al2O3 (8.89%), TiO2 (0.47%), Li (116????g/g), F (286????g/g), Ga (18????g/g), Se (6.1????g/g), Sr (350????g/g), Zr (268????g/g), REEs (172????g/g), Pb (30????g/g), and Th (17????g/g). The elements are classified into five associations by cluster analysis, i.e. Groups A, B, C, D, and E. Group A (ash-SiO2-Al2O3-Na2O-Li) and Group B (REE-Sc-In-Y-K2O-Rb-Zr-Hf-Cs-U-P2O5-Sr-Ba-Ge) are strongly correlated with ash yield and mainly have an inorganic affinity. The elements that are negatively or less strongly correlated with ash yield (with exceptions of Fe2O3, Be, V, and Ni) are grouped in the remaining three associations: Group C, Se-Pb-Hg-Th-TiO2-Bi-Nb-Ta-Cd-Sn; Group D, Co-Mo-Tl-Be-Ni-Sb-MgO-Re-Ga-W-Zn-V-Cr-F-Cu; and Group E, S-As-CaO-MnO-Fe2O3. Aluminum is mainly distributed in boehmite, followed by kaolinite. The high correlation coefficients of the Li-ash, Li-Al2O3, and Li-SiO2 pairs indicate that Li is related to the aluminosilicates in the coal. The boehmite-rich coal is high in gallium and F, which occur in boehmite and the

  7. Thermodynamic properties of water solvating biomolecular surfaces

    Science.gov (United States)

    Heyden, Matthias

    Changes in the potential energy and entropy of water molecules hydrating biomolecular interfaces play a significant role for biomolecular solubility and association. Free energy perturbation and thermodynamic integration methods allow calculations of free energy differences between two states from simulations. However, these methods are computationally demanding and do not provide insights into individual thermodynamic contributions, i.e. changes in the solvent energy or entropy. Here, we employ methods to spatially resolve distributions of hydration water thermodynamic properties in the vicinity of biomolecular surfaces. This allows direct insights into thermodynamic signatures of the hydration of hydrophobic and hydrophilic solvent accessible sites of proteins and small molecules and comparisons to ideal model surfaces. We correlate dynamic properties of hydration water molecules, i.e. translational and rotational mobility, to their thermodynamics. The latter can be used as a guide to extract thermodynamic information from experimental measurements of site-resolved water dynamics. Further, we study energy-entropy compensations of water at different hydration sites of biomolecular surfaces. This work is supported by the Cluster of Excellence RESOLV (EXC 1069) funded by the Deutsche Forschungsgemeinschaft.

  8. Hydrodynamic slip length as a surface property

    Science.gov (United States)

    Ramos-Alvarado, Bladimir; Kumar, Satish; Peterson, G. P.

    2016-02-01

    Equilibrium and nonequilibrium molecular dynamics simulations were conducted in order to evaluate the hypothesis that the hydrodynamic slip length is a surface property. The system under investigation was water confined between two graphite layers to form nanochannels of different sizes (3-8 nm). The water-carbon interaction potential was calibrated by matching wettability experiments of graphitic-carbon surfaces free of airborne hydrocarbon contamination. Three equilibrium theories were used to calculate the hydrodynamic slip length. It was found that one of the recently reported equilibrium theories for the calculation of the slip length featured confinement effects, while the others resulted in calculations significantly hindered by the large margin of error observed between independent simulations. The hydrodynamic slip length was found to be channel-size independent using equilibrium calculations, i.e., suggesting a consistency with the definition of a surface property, for 5-nm channels and larger. The analysis of the individual trajectories of liquid particles revealed that the reason for observing confinement effects in 3-nm nanochannels is the high mobility of the bulk particles. Nonequilibrium calculations were not consistently affected by size but by noisiness in the smallest systems.

  9. Relationships between waste physicochemical properties, microbial activity and vegetation at coal ash and sludge disposal sites.

    Science.gov (United States)

    Woch, Marcin W; Radwańska, Magdalena; Stanek, Małgorzata; Łopata, Barbara; Stefanowicz, Anna M

    2018-06-11

    The aim of the study was to assess the relationships between vegetation, physicochemical and microbial properties of substrate at coal ash and sludge disposal sites. The study was performed on 32 plots classified into 7 categories: dried ash sedimentation ponds, dominated by a grass Calamagrostis epigejos (AH-Ce), with the admixture of Pinus sylvestris (AH-CePs) or Robinia pseudoacacia (AH-CeRp), dry ash landfill dominated by Betula pendula and Pinus sylvestris (AD-BpPs) or Salix viminalis (AD-Sv) and coal sludge pond with drier parts dominated by Tussilago farfara (CS-Tf) and the wetter ones by Cyperus flavescens (CS-Cf). Ash sites were covered with soil layer imported as a part of technical reclamation. Ash had relatively high concentrations of some alkali and alkaline earth metals, Mn and pH, while coal sludge had high water and C, S, P and K contents. Concentrations of heavy metals were lower than allowable limits in all substrate types. Microbial biomass and, particularly, enzymatic activity in ash and sludge were generally low. The only exception were CS-Tf plots characterized by the highest microbial biomass, presumably due to large deposits of organic matter that became available for aerobic microbial biomass when water level fell. The properties of ash and sludge adversely affected microbial biomass and enzymatic activity as indicated by significant negative correlations between the content of alkali/alkaline earth metals, heavy metals, and macronutrients with enzymatic activity and/or microbial biomass, as well as positive correlations of these parameters with metabolic quotient (qCO 2 ). Plant species richness and cover were relatively high, which may be partly associated with alleviating influence of soil covering the ash. The effect of the admixture of R. pseudoacacia or P. sylvestris to stands dominated by C. epigejos was smaller than expected. The former species increased NNH 4 , NNO 3 and arylsulfatase activity, while the latter reduced activity of

  10. Geochemical evolution of acidic ground water at a reclaimed surface coal mine in western Pennsylvania

    Science.gov (United States)

    Cravotta,, Charles A.

    1991-01-01

    Concentrations of dissolved sulfate and acidity in ground water increase downflow in mine spoil and underlying bedrock at a reclaimed surface coal mine in the bituminous field of western Pennsylvania. Elevated dissolved sulfate and negligible oxygen in ground water from bedrock about 100 feet below the water table suggest that pyritic sulfur is oxidized below the water table, in a system closed to oxygen. Geochemical models for the oxidation of pyrite (FeS2) and production of sulfate (SO42-) and acid (H+) are presented to explain the potential role of oxygen (O2) and ferric iron (Fe3+) as oxidants. Oxidation of pyrite by O2 and Fe3+ can occur under oxic conditions above the water table, whereas oxidation by Fe3+ also can occur under anoxic conditions below the water table. The hydrated ferric-sulfate minerals roemerite [Fe2+Fe43+(SO4)4·14H2O], copiapite [Fe2+Fe43+(SO4)6(OH)2·20H20], and coquimbite [Fe2(SO4)3·9H2O] were identified with FeS2 in coal samples, and form on the oxidizing surface of pyrite in an oxic system above the water table. These soluble ferric-sulfate 11 salts11 can dissolve with recharge waters or a rising water table releasing Fe3+, SO42-. and H+, which can be transported along closed-system ground-water flow paths to pyrite reaction sites where O2 may be absent. The Fe3+ transported to these sites can oxidize pyritic sulfur. The computer programs WATEQ4F and NEWBAL were used to compute chemical speciation and mass transfer, respectively, considering mineral dissolution and precipitation reactions plus mixing of waters from different upflow zones. Alternative mass-balance models indicate that (a) extremely large quantities of O2, over 100 times its aqueous solubility, can generate the observed concentrations of dissolved SO42- from FeS2, or (b) under anoxic conditions, Fe3+ from dissolved ferric-sulfate minerals can oxidize FeS2 along closed-system ground-water flow paths. In a system open to O2, such as in the unsaturated zone, the aqueous

  11. Study of Coal Burst Source Locations in the Velenje Colliery

    Directory of Open Access Journals (Sweden)

    Goran Vižintin

    2016-06-01

    Full Text Available The Velenje coal mine (VCM is situated on the largest Slovenian coal deposit and in one of the thickest layers of coal known in the world. The thickness of the coal layer causes problems for the efficiency of extraction, since the majority of mining operations is within the coal layer. The selected longwall coal mining method with specific geometry, increasing depth of excavations, changes in stress state and naturally given geomechanical properties of rocks induce seismic events. Induced seismic events can be caused by caving processes, blasting or bursts of coal or the surrounding rock. For 2.5D visualization, data of excavations, ash content and calorific value of coal samples, hanging wall and footwall occurrence, subsidence of the surface and coal burst source locations were collected. Data and interpolation methods available in software package Surfer®12 were statistically analyzed and a Kriging (KRG interpolation method was chosen. As a result 2.5D visualizations of coal bursts source locations with geomechanical properties of coal samples taken at different depth in the coal seam in the VCM were made with data-visualization packages Surfer®12 and Voxler®3.

  12. Surface properties of copper based cermet materials

    International Nuclear Information System (INIS)

    Voinea, M.; Vladuta, C.; Bogatu, C.; Duta, A.

    2008-01-01

    The paper presents the characterization of the surface properties of copper based cermets obtained by two different techniques: spray pyrolysis deposition (SPD) and electrodeposition. Copper acetate was used as precursor of Cu/CuO x cermet. The surface morphology was tailored by adding copolymers of maleic anhydride with controlled hydrophobia. The films morphology of Cu/CuO x was assessed using contact angle measurements and AFM analysis. The porous structures obtained via SPD lead to higher liquid adsorption rate than the electrodeposited films. A highly polar liquid - water is recommended as testing liquid in contact angle measurements, for estimating the porosity of copper based cermets, while glycerol can be used to distinguish among ionic and metal predominant structures. Thus, contact angle measurements can be used for a primary evaluation of the films morphology and, on the other hand, of the ratio between the cermet components

  13. Characterization of interactions of coal surface with solvent by flow microcalorimetric measurement. 3; Netsuryo sokutei ni yoru sekitan hyomen to yozai tono sogo sayo no hyoka. 3

    Energy Technology Data Exchange (ETDEWEB)

    Wang, N.; Sasaki, M.; Yoshida, T. [Hokkaido National Industrial Research Institute, Sapporo (Japan); Kotanigawa, T. [Japan International Corporation Agency, Tokyo (Japan)

    1996-10-28

    An investigation was given on the relationship between methanol adsorbing behavior of reformed coal surface and oxygen containing functional groups in coal. Akabira bituminous coal was air-oxidized or Yallourn brown coal was decarbonated in oil as a reformation treatment. Both of the treated and untreated coals showed an adsorption heat curve of the Langmuir type. The Akabira coal had its oxygen content and the adsorption heat increased as a result of the air oxidizing reformation treatment. The Yallourn coal had its oxygen content and adsorption heat decreased as a result decarbonation reformation treatment. Oxygen containing functional groups act as strong adsorption sites for methanol, and the maximum adsorption amount depends on oxygen content in the coals. Since the coal surface is non-uniform in terms of energy, methanol is adsorbed first into sites with higher molar adsorption heat, and then into lower sites sequentially. Therefore, distribution of the molar adsorption heat can be derived from the relationship between adsorption amount and adsorption heat by changing methanol adsorption amount. The distribution of molar adsorption heat becomes broader when the oxygen content is high, and narrower when low. 2 refs., 2 figs.

  14. Role of soil health in maintaining environmental sustainability of surface coal mining.

    Science.gov (United States)

    Acton, Peter M; Fox, James F; Campbell, J Elliott; Jones, Alice L; Rowe, Harold; Martin, Darren; Bryson, Sebastian

    2011-12-01

    Mountaintop coal mining (MCM) in the Southern Appalachian forest region greatly impacts both soil and aquatic ecosystems. Policy and practice currently in place emphasize water quality and soil stability but do not consider upland soil health. Here we report soil organic carbon (SOC) measurements and other soil quality indicators for reclaimed soils in the Southern Appalachian forest region to quantify the health of the soil ecosystem. The SOC sequestration rate of the MCM soils was 1.3 MgC ha(-1) yr(-1) and stocks ranged from 1.3 ± 0.9 to 20.9 ± 5.9 Mg ha(-1) and contained only 11% of the SOC of surrounding forest soils. Comparable reclaimed mining soils reported in the literature that are supportive of soil ecosystem health had SOC stocks 2.5-5 times greater than the MCM soils and sequestration rates were also 1.6-3 times greater. The high compaction associated with reclamation in this region greatly reduces both the vegetative rooting depth and infiltration of the soil and increases surface runoff, thus bypassing the ability of soil to naturally filter groundwater. In the context of environmental sustainability of MCM, it is proposed that the entire watershed ecosystem be assessed and that a revision of current policy be conducted to reflect the health of both water and soil.

  15. Geological Factors and Reservoir Properties Affecting the Gas Content of Coal Seams in the Gujiao Area, Northwest Qinshui Basin, China

    Directory of Open Access Journals (Sweden)

    Zhuo Zou

    2018-04-01

    Full Text Available Coalbed methane (CBM well drilling and logging data together with geological data were adopted to provide insights into controlling mechanism of gas content in major coal seams and establish gas accumulation models in the Gujiao area, Northwest Qinshui Basin, China. Gas content of targeted coals is various in the Gujiao area with their burial depth ranging from 295 to 859 m. Highly variable gas content of coals should be derived from the differences among tectonism, magmatism, hydrodynamism, and sedimentation. Gas content preserved in the Gujiao area is divided into two parts by the geological structure. Gas tends to accumulate in the groundwater stagnant zone with a total dissolved solids (TDS value of 1300–1700 ppm due to water pressure in the Gujiao area. Reservoir properties including moisture content, minerals, and pore structure also significantly result in gas content variability. Subsequently, the gray correlation statistic method was adopted to determine the most important factors controlling gas content. Coal metamorphism and geological structure had marked control on gas content for the targeted coals. Finally, the favorable CBM exploitation areas were comprehensively evaluated in the Gujiao area. The results showed that the most favorable CBM exploitation areas were in the mid-south part of the Gujiao area (Block I.

  16. Analysis of the relationship between the coal properties and their liquefaction characteristics by using the coal data base; Tanshu data base ni yoru tanshitsu to ekika tokusei no kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Kanbayashi, Y.; Okada, K. [Coal Mining Research Center, Tokyo (Japan)

    1996-10-28

    The relationship between coal properties and liquefaction or gasification characteristics was analyzed by using the analysis and test results and liquefaction characteristics in the coal data base. On liquefaction reaction, the close relation between an oil yield and coal constituent composition or a coal rank is well-known. Various multivariable regression analyses were conducted by using 6 factors as variables such as calorific value, volatile component, O/C and H/C atomic ratios, exinite+vitrinite content and vitrinite reflectance, and liquefaction characteristics as variate. On liquefaction characteristics, the oil yield of dehydrated and deashed coals, asphaltene yield, hydrogen consumption, produced water and gas quantities, and oil+asphaltene yield were predicted. The theoretical gasification efficiency of each specimen was calculated to evaluate the liquefaction reaction obtained. As a result, the oil yield increased with H/C atomic ratio, while the theoretical gasification efficiency increased with O/C atomic ratio. 5 figs., 1 tab.

  17. Reclamation Strategies and Geomorphic Outcomes in Coal Surface Mines of Eastern Ohio

    Science.gov (United States)

    Pollock, M.; Jaeger, K. L.

    2014-12-01

    Coal surface mining is a significant landscape disturbance in the United States. Since 1977, the reclamation of mined lands has been regulated by the Surface Mine Control and Reclamation Act (SMCRA). Prior to the act, many coalfields were left un-reclaimed or partially reclaimed, with highly irregular topology and drainage networks. Under the act, the reverse is often true; adherence to SMCRA often leads to the homogenization of surfaces and channel networks. While both pre and post-SMCRA landscapes are highly altered, they exhibit strongly dissimilar characteristics. We examine pre-SMCRA, post-SMCRA and unmined watersheds at 3 spatial scales in order to compare the geomorphic differences between reclamation strategies. In particular, we attempt to separate anthropogenic factors from pre-existing, natural factors via comparisons to unmined watersheds. Our study design incorporates a 3 scale top-down analysis of 21 independent watersheds (7 of each treatment type). Each watershed has an area of approximately 1km2. All watersheds share similar geography, climate and geology. At the landscape scale, characteristics are derived from 0.762m (2.5ft) resolution Digital Elevation Models (DEMs). At the channel network scale, DEMs, as well as remote sensing data (including the National Wetlands Inventory database) are used. Finally, the reach scale incorporates longitudinal and cross-section surveys (using a total station) as well as a particle size distribution. At each scale, attributes are parameterized for statistical comparison. Post-SMCRA sites are characterized by a general reduction of watershed surface slopes (11.9% median) compared to pre-SMCRA (19.3%) and unmined (19.8%) sites. Both pre and post-SMCRA channel networks are characterized by significant surface impoundments (in the form of remnant headwall trenches on pre-SMCRA sites and engineered retention basins on post-SMCRA sites). Pre-SMCRA outlet reaches have significantly steeper bed slopes (2.79% mean) than

  18. CoalVal-A coal resource valuation program

    Science.gov (United States)

    Rohrbacher, Timothy J.; McIntosh, Gary E.

    2010-01-01

    CoalVal is a menu-driven Windows program that produces cost-of-mining analyses of mine-modeled coal resources. Geological modeling of the coal beds and some degree of mine planning, from basic prefeasibility to advanced, must already have been performed before this program can be used. United States Geological Survey mine planning is done from a very basic, prefeasibility standpoint, but the accuracy of CoalVal's output is a reflection of the accuracy of the data entered, both for mine costs and mine planning. The mining cost analysis is done by using mine cost models designed for the commonly employed, surface and underground mining methods utilized in the United States. CoalVal requires a Microsoft Windows? 98 or Windows? XP operating system and a minimum of 1 gigabyte of random access memory to perform operations. It will not operate on Microsoft Vista?, Windows? 7, or Macintosh? operating systems. The program will summarize the evaluation of an unlimited number of coal seams, haulage zones, tax entities, or other area delineations for a given coal property, coalfield, or basin. When the reader opens the CoalVal publication from the USGS website, options are provided to download the CoalVal publication manual and the CoalVal Program. The CoalVal report is divided into five specific areas relevant to the development and use of the CoalVal program: 1. Introduction to CoalVal Assumptions and Concepts. 2. Mine Model Assumption Details (appendix A). 3. CoalVal Project Tutorial (appendix B). 4. Program Description (appendix C). 5. Mine Model and Discounted Cash Flow Formulas (appendix D). The tutorial explains how to enter coal resource and quality data by mining method; program default values for production, operating, and cost variables; and ones own operating and cost variables into the program. Generated summary reports list the volume of resource in short tons available for mining, recoverable short tons by mining method; the seam or property being mined

  19. Coal chemistry and technology. Komur Kimyasi ve Teknolojisi

    Energy Technology Data Exchange (ETDEWEB)

    Kural, O [ed.

    1988-01-01

    The 18 chapters cover the following topics: mining in Turkey; formation, petrography and classification of coal; chemical and physical properties of coal; mechanical properties of coal; spontaneous combustion of coal and the methods of prevention; sampling of coal; coal preparation and plants; desulfurization of coal; bituminous coal and its consumption; lignite and its consumption; world coal trade and transportation; other important carbon fuels; briquetting of coal; carbonization and coking formed coke; liquefaction of coal; gasification of coal; underground gasification of coal; and combustion models, fluidized-bed combustion, furnaces. An English-Turkish coal dictionary is included. 641 refs., 244 figs., 108 tabs.

  20. Surface and conductivity properties of imidazoles solutions

    International Nuclear Information System (INIS)

    Rogalski, Marek; Domanska, Urszula; Czyrny, Dagmara; Dyczko, Dagmara

    2002-01-01

    The surface tension, σ, of the solutions of benzimidazole, 2-phenylimidazole and 2,4,5-triphenylimidazole in water, or water + 10 mol% of acetonitrile, or in other solvents as well as the solubilities and conductivity of benzimidazole and 2-phenylimidazole in water in function of concentration at 298.15 K were measured. The enthalpy of fusion, or solid-solid phase transition and the melting temperatures were determined for the substances under study by the scanning calorimetry (DSC). These solutions exhibit, in a wide range of concentrations, the normal linear, or parabolic decreasing dependencies and the maximum of surface tension at very low concentrations and show the S-shaped dependencies, being in function of the initial sample, never reported before. The results were confirmed by the conductivity measurements. The results were interpreted in terms of the changing structure of the interface. It was concluded that the observed phenomena were caused by an induced nucleation of benzimidazole, 2-phenylimidazole and especially by 2,4,5-triphenylimidazole by columnar discotic structures due to the initial concentration. The surface properties of these solutions reflect the interactions of hydrophobic parts of the guest molecules adsorbed at the interface, as a result of the hydrogen bonded structure of the solution

  1. P-ANFO: new era in surface coal mining; P-ANFO: acik ocak komur isletmeciliginde yeni bir cag

    Energy Technology Data Exchange (ETDEWEB)

    Tek, A. [Atlas Ltd., Istanbul (Turkey)

    1999-07-01

    ANFO, an effective and inexpensive explosive, is widely used in rock blasting operations. However, for weak strata, ANFO often produces too much shock energy and leads to inefficiencies in the mining operation. Especially in Turkish surface coal mines where ANFO is used with the decking system, it is desirable to develop a low shock energy but a high heave energy ammonium nitrate based explosive. 3 refs., 9 figs., 1 tab.

  2. Development of tools for managing the impacts on surface due to changing hydrological regimes surrounding closed underground coal mines (ECSC Coal RTD programme, contract 7220-PR-136)

    International Nuclear Information System (INIS)

    Veschkens, M.; Unland, W.; Kories, H.

    2005-01-01

    This paper demonstrates how box model approach and FE and box mixed model approach allow to better understand and model water flows in complex mined coal measures and interactions between shallow aquifers and flooded coal measures. Benefits of these approaches are illustrated on the basis of case studies in Liege and Ruhr coal basins. (authors)

  3. Development of tools for managing the impacts on surface due to changing hydrological regimes surrounding closed underground coal mines (ECSC Coal RTD programme, contract 7220-PR-136)

    Energy Technology Data Exchange (ETDEWEB)

    Veschkens, M. [ISSeP, Liege (Belgium); Unland, W.; Kories, H. [DMT, Am Technologiepark, Essen (Germany)

    2005-07-01

    This paper demonstrates how box model approach and FE and box mixed model approach allow to better understand and model water flows in complex mined coal measures and interactions between shallow aquifers and flooded coal measures. Benefits of these approaches are illustrated on the basis of case studies in Liege and Ruhr coal basins. (authors)

  4. Modes of occurrence of fluorine in the Late Paleozoic No. 6 coal from the Haerwusu Surface Mine, Inner Mongolia, China

    Energy Technology Data Exchange (ETDEWEB)

    Xibo Wang; Shifeng Dai; Yingying Sun; Dan Li; Weiguo Zhang; Yong Zhang; Yangbing Luo [China University of Mining and Technology, Beijing (China). State Key Laboratory of Coal Resources and Safe Mining

    2011-01-15

    The No. 6 coal from the Haerwusu Surface Mine, Inner Mongolia, China, is enriched in Al and Ga, which are valuable metal resources that could be extracted from fly ash. However, fluorine in the coal is unusually high (mean 286 {mu}g/g) and potentially toxic to the environment in the extraction process. In this paper, a sequential extraction/density separation procedure (SE/DS) was designed to examine the modes of occurrence of fluorine in the coal. The results show that fluorine extracted in distilled water, NH{sub 4}Ac (1 mol/l), and HCl (0.5%) leachates is low, and that in sulfide fraction is below the detection limit. The organic and silicate associations are inferred to account for more than 90% of the total fluorine in the coal. Boehmite and kaolinite are prime carriers of fluorine (the fluorine content in silicate fraction of the boehmite-enriched sample H-14 is up to 1906 {mu}g/g, and that of the kaolinite-enriched sample H-29 is 384 {mu}g/g). In bench samples H-2 and H-3, a minor amount of fluorine is related to goyazite. The relationship between fluorine and boehmite indicates that they were probably derived from the sediment source region, the weathered bauxite of the uplifted Benxi formation. 29 refs., 7 figs., 3 tabs.

  5. A Comprehensive Review on the Properties of Coal Bottom Ash in Concrete as Sound Absorption Material

    OpenAIRE

    Ramzi Hannan Nurul Izzati Raihan; Shahidan Shahiron; Ali Noorwirdawati; Maarof Mohamad Zulkhairi

    2017-01-01

    The government is currently implementing policies to increase the usage of coal as fuel for electricity generation. At the same time, the dependency on gas will be reduced. In addition, coal power plants in Malaysia produce large amounts of industrial waste such as bottom ash which is collected in impoundment ponds (ash pond). However, millions of tons of coal ash (bottom ash) waste are collected in ponds near power plant stations. Since bottom ash has been classified as hazardous material th...

  6. Coal background paper. Coal demand

    International Nuclear Information System (INIS)

    1997-01-01

    Statistical data are presented on coal demands in IEA and OECD member countries and in other countries. Coal coaking and coaking coal consumption data are tabulated, and IEA secretariat's coal demand projections are summarized. Coal supply and production data by countries are given. Finally, coal trade data are presented, broken down for hard coal, steam coal, coking coal (imports and export). (R.P.)

  7. Identification of linkages between potential Environmental and Social Impacts of Surface Mining and Ecosystem Services in Thar Coal field, Pakistan

    Science.gov (United States)

    Hina, A.

    2017-12-01

    Although Thar coal is recognized to be one of the most abundant fossil fuel that could meet the need to combat energy crisis of Pakistan, but there still remains a challenge to tackle the associated environmental and socio-ecological changes and its linkage to the provision of ecosystem services of the region. The study highlights the importance of considering Ecosystem service assessment to be undertaken in all strategic Environmental and Social Assessments of Thar coal field projects. The three-step approach has been formulated to link the project impacts to the provision of important ecosystem services; 1) Identification of impact indicators and parameters by analyzing the environmental and social impacts of surface mining in Thar Coal field through field investigation, literature review and stakeholder consultations; 2) Ranking of parameters and criteria alternatives using Multi-criteria Decision Analysis(MCDA) tool: (AHP method); 3) Using ranked parameters as a proxy to prioritize important ecosystem services of the region; The ecosystem services that were prioritized because of both high significance of project impact and high project dependence are highlighted as: Water is a key ecosystem service to be addressed and valued due to its high dependency in the area for livestock, human wellbeing, agriculture and other purposes. Crop production related to agricultural services, in association with supply services such as soil quality, fertility, and nutrient recycling and water retention need to be valued. Cultural services affected in terms of land use change and resettlement and rehabilitation factors are recommended to be addressed. The results of the analysis outline a framework of identifying these linkages as key constraints to foster the emergence of green growth and development in Pakistan. The practicality of implementing these assessments requires policy instruments and strategies to support human well-being and social inclusion while minimizing

  8. Activated carbons from Mongolian coals by thermal treatment

    Directory of Open Access Journals (Sweden)

    A Ariunaa

    2014-09-01

    Full Text Available Mongolian different rank coals were used as raw material to prepare activatedcarbons by physical activation method. The coal derived carbons were oxidized with nitric acid in order to introduce surface oxygen groups. The ultimate elemental analysis, scanning electron microscopy, surface area, pore size distribution analysis and selective neutralization method were used to characterize the surface properties of activated carbons, oxidizedcarbons and raw coals. The effect of coal grade on the adsorption properties of the carbons were studied. It was concluded that Naryn sukhait bituminous coal could be serve as suitable raw material for production of activated carbons for removal of heavy metal ions from solution.DOI: http://dx.doi.org/10.5564/mjc.v12i0.174 Mongolian Journal of Chemistry Vol.12 2011: 60-64

  9. Effects of surface coal mining and reclamation on the geohydrology of six small watersheds in west-central Indiana. Chapter B

    International Nuclear Information System (INIS)

    Martin, J.D.; Duwelius, R.F.; Crawford, C.G.

    1990-01-01

    Coal has been and will continue to be a major source of energy in the United States for the foreseeable future. Surface mining is presently the most efficient method of extracting coal. The mining practice, however, usually has a detrimental effect on the environment by altering topography and ecologic systems. Surface coal mining also can degrade surface- and ground-water quality and quantity. The U.S. Geological Survey began a study in 1979 to identify changes in the quantity of surface- and ground-water resources caused by surface coal mining in Indiana. As part of the study, six small watersheds in west-central Indiana were instrumented for the collection of hydrologic and meteorologic data. The Water-Supply Paper comprises two reports resulting from the investigation. The physical environment and coal mining history of west-central Indiana and the six small watersheds selected for intensive study are described in chapter A. The surface- and ground-water systems of each of the small watersheds and the hydrologic effects of coal mining and reclamation are described in chapter B

  10. Size- and shape-dependent surface thermodynamic properties of nanocrystals

    Science.gov (United States)

    Fu, Qingshan; Xue, Yongqiang; Cui, Zixiang

    2018-05-01

    As the fundamental properties, the surface thermodynamic properties of nanocrystals play a key role in the physical and chemical changes. However, it remains ambiguous about the quantitative influence regularities of size and shape on the surface thermodynamic properties of nanocrystals. Thus by introducing interface variables into the Gibbs energy and combining Young-Laplace equation, relations between the surface thermodynamic properties (surface Gibbs energy, surface enthalpy, surface entropy, surface energy and surface heat capacity), respectively, and size of nanocrystals with different shapes were derived. Theoretical estimations of the orders of the surface thermodynamic properties of nanocrystals agree with available experimental values. Calculated results of the surface thermodynamic properties of Au, Bi and Al nanocrystals suggest that when r > 10 nm, the surface thermodynamic properties linearly vary with the reciprocal of particle size, and when r < 10 nm, the effect of particle size on the surface thermodynamic properties becomes greater and deviates from linear variation. For nanocrystals with identical equivalent diameter, the more the shape deviates from sphere, the larger the surface thermodynamic properties (absolute value) are.

  11. Coal-bed methane water: effects on soil properties and camelina productivity

    Science.gov (United States)

    Every year the production of coal-bed natural gas in the Powder River Basin results in the discharge of large amounts of coal-bed methane water (CBMW) in Wyoming; however, no sustainable disposal methods for CBMW are currently available. A greenhouse study was conducted to evaluate the potential to ...

  12. Effect of bituminous coal properties on carbon dioxide and methane high pressure sorption

    Czech Academy of Sciences Publication Activity Database

    Weishauptová, Zuzana; Přibyl, Oldřich; Sýkorová, Ivana; Machovič, Vladimír

    2015-01-01

    Roč. 139, JAN 1 (2015), s. 115-124 ISSN 0016-2361 Institutional support: RVO:67985891 Keywords : bituminous coal * sorption capacity * maceral composition * Upper Silesian Coal Basin Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.611, year: 2015

  13. Formation of clinker and its effects on locating and limiting coal resources

    International Nuclear Information System (INIS)

    Sarnecki, J.C.

    1991-01-01

    Coal burns occur in nature primarily due to spontaneous combustion and the result is baked overburden known as clinker. Understanding occurrences of natural coal burns and formation of clinker is important for coal resource exploration and development. Clinker is an indication of potential commercial coal reserves, and can be located easily due to its difference from the unaltered coal section, especially color, geochemical properties, and aquifer properties. The high porosity and variable material strength of clinker create impacts for aspects of mine development such as foundation planning, slope stability, and water handling. This paper describes the formation of clinker, the use of clinker for coal deposit location, its effect on coal quality, its effect on coal resource development, and the use of clinker in surface mine reclamation

  14. Accumulation of dissolved gases at hydrophobic surfaces in water and sodium chloride solutions: Implications for coal flotation

    Energy Technology Data Exchange (ETDEWEB)

    Hampton, M.A.; Nguyen, A.V. [University of Queensland, Brisbane, Qld. (Australia). Division of Chemical Engineering

    2009-08-15

    Dissolved gases can preferentially accumulate at the hydrophobic solid-water interface as revealed by neutron reflectivity measurements. In this paper, atomic force microscopy (AFM) was used to examine accumulation of dissolved gases at a hydrophobic surface in water and sodium chloride solutions. The solvent-exchange method was used to artificially form gaseous domains accumulated at the interface suitable for AFM imaging. Smooth graphite surfaces were used as model surfaces to minimize the secondary effect of surface roughness on the imaging. The concentration of NaCl up to 1 M was found to have a negligible influence on the geometry and population of pre-existing nanobubbles, nanopancakes and nanobubble-nanopancake composites. The implications of the findings on coal flotation in saline water are discussed in terms of attraction between hydrophobic surfaces in water, bubble-particle attachment and hydrophobic coagulation between particles.

  15. Examining microbial community response to a strong chemical gradient: the effects of surface coal mining on stream bacteria

    Science.gov (United States)

    Bier, R.; Lindberg, T. T.; Wang, S.; Ellis, J. C.; Di Giulio, R. T.; Bernhardt, E. S.

    2012-12-01

    Surface coal mining is the dominant form of land cover change in northern and central Appalachia. In this process, shallow coal seams are exposed by removing overlying rock with explosives. The resulting fragmented carbonate rock and coal residues are disposed of in stream valleys. These valley fills generate alkaline mine drainage (AlkMD), dramatically increasing alkalinity, ionic strength, substrate supply (esp. SO42-), and trace element (Mn, Li, Se, U) concentrations in downstream rivers as well as significant losses of sensitive fish and macroinvertebrate species. In prior work within the Mud River, which drains the largest surface mine complex in Appalachia, we found that concentrations of AlkMD increase proportionally with the extent of upstream mining. Here we ask "How do stream microbial communities change along this strong chemical gradient?" We collected surface water and benthic biofilms from 25 stream reaches throughout the Mud River spanning the full range of surface mining impacts, with 0-96% of the contributing watershed area converted to surface coal mines. Microbial communities were collected from biofilms grown on a common substrate (red maple veneers) that were incubated in each stream reach for four months prior to collection in April, 2011. 16S rRNA genes from microbial communities at each study site were examined using 454 sequencing and compared with a generalized UniFrac distance matrix (674 sequence eveness) that was used in statistical analyses. Water chemistry at the sites was sampled monthly from July 2010 to December 2010 and again in April 2011. In April, surface water concentrations of SO42-, Ca2+, Mg2+, and Se2- increased linearly with the extent of upstream mining (all regressions R2 >0.43; pPERMANOVA; p=0.029). Bacterial diversity (OTU richness defined at 3% sequence difference) peaked at intermediate conductivities (600 μS cm-1). Environmental data that correlated significantly with the ordination axes were a variety of surface

  16. SAMPLING, ANALYSIS, AND PROPERTIES OF PRIMARY PM-2.5: APPLICATION TO COAL-FIRED UTILITY BOILERS

    Energy Technology Data Exchange (ETDEWEB)

    Allen L. Robinson; Spyros N. Pandis; Eric Lipsky; Charles Stainer; Natalie Anderson; Satoshi Takahama; Sarah Rees

    2003-02-01

    A dilution sampler was used to examine the effects of dilution ratio and residence time on the particulate emissions from a pilot-scale pulverized coal combustor. Measurements include the particle size distribution from 0.003 to 2.5 {micro}m, PM{sub 2.5} mass emission rate and PM2.5 composition (OC/EC, major ions, and elemental). Hot filter samples were also collected simultaneously in order to compare the dilution sampler measurement with standard stack sampling methodologies such as EPA Method 5. Measurements were made both before and after the bag-house, the particle control device used on the coal combustor. Measurements were made with three different coal types and a coal-biomass blend. The residence time and dilution ratio do not influence the PM{sub 2.5} mass emission rate, but have a significant effect on the size distribution and total number emissions. Measurements made before the bag-house showed increasing the residence time dramatically decreases the total particle number concentration, and shifts the particle mass to larger sizes. The effects of residence time can be explained quantitatively by the coagulation of the emitted particles. Measurements made after the bag-house were not affected by coagulation due to the lower concentration of particles. Nucleation of sulfuric acid vapor within the dilution was an important source of ultrafine particles. This nucleation is strongly a function of dilution ratio because of the competition between condensation and nucleation. At low dilution ratios condensation dominates and little nucleation is observed; increasing the dilution ratio promotes nucleation because of the corresponding decrease in available surface area per unit volume for condensation. No nucleation was observed after the bag house where conditions greatly favor nucleation over condensation; we suspect that the bag house removed the SO{sub 3} in the flue gas. Exhaust SO{sub 3} levels were not measured during these experiments. Dilution caused

  17. The properties of the nano-minerals and hazardous elements: Potential environmental impacts of Brazilian coal waste fire.

    Science.gov (United States)

    Civeira, Matheus S; Pinheiro, Rafael N; Gredilla, Ainara; de Vallejuelo, Silvia Fdez Ortiz; Oliveira, Marcos L S; Ramos, Claudete G; Taffarel, Silvio R; Kautzmann, Rubens M; Madariaga, Juan Manuel; Silva, Luis F O

    2016-02-15

    Brazilian coal area (South Brazil) impacted the environment by means of a large number of coal waste piles emplaced over the old mine sites and the adjacent areas of the Criciúma, Urussanga, and Siderópolis cities. The area studied here was abandoned and after almost 30 years (smokeless visual) some companies use the actual minerals derived from burning coal cleaning rejects (BCCRs) complied in the mentioned area for industry tiles or refractory bricks. Mineralogical and geochemical similarities between the BCCRs and non-anthropogenic geological environments are outlined here. Although no visible flames were observed, this study revealed that auto-combustion existed in the studied area for many years. The presence of amorphous phases, mullite, hematite and other Fe-minerals formed by high temperature was found. There is also pyrite, Fe-sulphates (eg. jarosite) and unburnt coal present, which are useful for comparison purposes. Bad disposal of coal-dump wastes represents significant environmental concerns due to their potential influence on atmosphere, river sediments, soils and as well as on the surface and groundwater in the surroundings of these areas. The present study using advanced analytical techniques were performed to provide an improved understanding of the complex processes related with sulphide-rich coal waste oxidation, spontaneous combustion and mineral formation. It is reporting huge numbers of rare minerals with alunite, montmorillonite, szomolnokite, halotrichite, coquimbite and copiapite at the BCCRs. The data showed the presence of abundant amorphous Si-Al-Fe-Ti as (oxy-)hydroxides and Fe-hydro/oxides with goethite and hematite with various degrees of crystallinity, containing hazardous elements, such as Cu, Cr, Hf, Hg, Mo, Ni, Se, Pb, Th, U, Zr, and others. By Principal Component Analysis (PCA), the mineralogical composition was related with the range of elemental concentration of each sample. Most of the nano-minerals and ultra-fine particles

  18. Infrared optical properties of a coal-fired power plant plume

    International Nuclear Information System (INIS)

    Stearns, L.P.; Pueschel, R.F.

    1983-01-01

    Infrared measurements in the 8--14-μm spectral region were made of two coal-fired power plant plumes and area haze in the Four Corners region of New Mexico from 1 to 7 Nov. 1980. The layer tranmittance, optical depth, and volume extinction coefficient derived from measurements on four nonconsecutive days show the effects of the plumes on the IR optical properties of the atmosphere. The average contribution of the plume alone to the IR extinction coefficient was 74% at the Four Corners plant; the background haze contributed 7--11%. More efficient particulate emission control at the San Juan power plant reduced the average contribution of its plume to 57% of the extinction coefficient. The haze contributed an average of 16%. The results show an increase with time of the haze bulk extinction coefficient during a persistent anticyclonic synoptic situation. Extinction coefficients of the haze showed a linearity with particulate loading, which led to estimates of IR volume extinctions of the free troposphre from aerosol measurements

  19. Properties and Developments of Combustion and Gasification of Coal and Char in a CO2-Rich and Recycled Flue Gases Atmosphere by Rapid Heating

    Directory of Open Access Journals (Sweden)

    Zhigang Li

    2012-01-01

    Full Text Available Combustion and gasification properties of pulverized coal and char have been investigated experimentally under the conditions of high temperature gradient of order 200°C·s−1 by a CO2 gas laser beam and CO2-rich atmospheres with 5% and 10% O2. The laser heating makes a more ideal experimental condition compared with previous studies with a TG-DTA, because it is able to minimize effects of coal oxidation and combustion by rapid heating process like radiative heat transfer condition. The experimental results indicated that coal weight reduction ratio to gases followed the Arrhenius equation with increasing coal temperature; further which were increased around 5% with adding H2O in CO2-rich atmosphere. In addition, coal-water mixtures with different water/coal mass ratio were used in order to investigate roles of water vapor in the process of coal gasification and combustion. Furthermore, char-water mixtures with different water/char mass ratio were also measured in order to discuss the generation ratio of CO/CO2, and specified that the source of Hydrocarbons is volatile matter from coal. Moreover, it was confirmed that generations of CO and Hydrocarbons gases are mainly dependent on coal temperature and O2 concentration, and they are stimulated at temperature over 1000°C in the CO2-rich atmosphere.

  20. An experimental study on the hazard assessment and mechanical properties of porous concrete utilizing coal bottom ash coarse aggregate in Korea.

    Science.gov (United States)

    Park, Seung Bum; Jang, Young Il; Lee, Jun; Lee, Byung Jae

    2009-07-15

    This study evaluates quality properties and toxicity of coal bottom ash coarse aggregate and analyzes mechanical properties of porous concrete depending on mixing rates of coal bottom ash. As a result, soundness and resistance to abrasion of coal bottom ash coarse aggregate were satisfied according to the standard of coarse aggregate for concrete. To satisfy the standard pertaining to chloride content, the coarse aggregates have to be washed more than twice. In regards to the result of leaching test for coal bottom ash coarse aggregate and porous concrete produced with these coarse aggregates, it was satisfied with the environment criteria. As the mixing rate of coal bottom ash increased, influence of void ratio and permeability coefficient was very little, but compressive and flexural strength decreased. When coal bottom ash was mixed over 40%, strength decreased sharply (compressive strength: by 11.7-27.1%, flexural strength: by maximum 26.4%). Also, as the mixing rate of coal bottom ash increased, it was confirmed that test specimens were destroyed by aggregate fracture more than binder fracture and interface fracture. To utilize coal bottom ash in large quantities, it is thought that an improvement method in regards to strength has to be discussed such as incorporation of reinforcing materials and improvement of aggregate hardness.

  1. Evaluation of the coal properties of Norte de Santander; Evaluacion de las propiedades de los carbones de Norte de Santander

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1987-07-01

    The Project Characterization of Coal of Norte de Santander, concluded in the second semester of 1986 with the presentation of the 4 final reports of the participant entities: Universidad Nacional de Colombia - Bogota, Universidad Francisco de Paula Santander, Instituto de Investigaciones Technologicas (I.I.T.), and Instituto de Investigaciones geologico Mineras - INGEOMINAS. In each Institution some common aspects were worked - analytic part and other specific topics, that which believes the necessity to develop a study that unified the parts worked jointly with the elaboration of a new chart of data, and it allowed this way to assemble the analytic base with the studies of some technological properties and of benefit. Initially it is made a summary of the most excellent aspects in the Geology, mining and Commercialization of the Coal of the department and later on with reference to all the available analytic information, new data were obtained with base in averages among Institutions, checkups of differing results, correlate and discard of rusty samples. For the chemical and physicochemical analyses, the plastic properties, the petrographic results, the chemical analysis of the ashes, they were made statistical and correlative new treatment discriminating against the different sectors and formations inside the area (the Formation Catatumbo was excepted). For the analyses more used as range indicators and others of quality were carried out three-dimensional graphic that summarize in a visual form the variation of the parameter through the study area and the sectors inside this being obtained the iso-values curves equally. The study of some properties of the coal related with technological processes like coking, liquefaction and of benefit they supplement the analytic characterization being able to obtain several practical conclusions as for the use of these coal and remarking some concrete problems to solve with the objective of improving the quality of the

  2. Developing new technology of coal coking

    Energy Technology Data Exchange (ETDEWEB)

    Erkin, L.I.; Nefedov, P.Ya.

    1981-03-01

    This paper characterizes types of coke (grain size, compression strength, abrasion, porosity) used by: blast furnaces, shaft furnaces, ferroalloys and phosphorus production, and ore agglomeration. Development of formed metallurgical coke production on the basis of technologies worked out by the Eastern Research Scientific Institute for Coal Chemistry is analyzed. The following phases in the investigations are stressed: optimization of coal blends (increasing proportion of coals with poor caking properties, pressing briquets, carbonization, temperature distribution and temperature control, using heat emitted by hot coke for coal preheating (heat consumption of coking is reduced to 200 kcal/kg). On the basis of technology developed and tested by VUKhIN formed coke consisting of 60% G6 coal and 40% 2SS coal has been produced. Using the coke in blast furnaces increases furnace capacity by 5% and reduces coke consumption in a furnace by 2.6%. It is suggested that wide use of the proposed technology of formed metallurgical coke production in the Kuzbass (using coals with poor caking properties from surface mines) would increase coke production of the region to 50 Mt for a year. technology of producing formed foundry coke from: 80 to 86% anthracites, semianthracites and coals with poor caking properties, 5 to 10% coking coal, and 8% binder is evaluated. Formed foundry coke produced from the blend reduces coke consumption in a foundry by 25 to 30% and increases cast iron temperature by 20 to 50/sup 0/C. Technologies of producing coke for phosphorus industry by continuous coking of coals difficult to coke in vertical coke ovens and production of coke for ore agglomeration are also discussed. (In Russian)

  3. 77 FR 62266 - Proposed Extension of Existing Information Collection; Daily Inspection of Surface Coal Mines...

    Science.gov (United States)

    2012-10-12

    ... conducting an on shift examination for hazardous conditions, mine operators better ensure a safe working environment for the miners and a reduction in accidents. II. Desired Focus of Comments The Mine Safety and... (30 CFR 77.1713) requires coal mine operators to conduct examinations of each active working area of...

  4. Heat and Mass Transfer at Hot Surface Ignition of Coal Particle

    OpenAIRE

    Glushkov Dmitrii O.; Kosintsev Andrey. G.; Shlegel Nikita E.; Vershinina Ksenia Yu.

    2015-01-01

    This paper describes the experimental investigations of the characteristics of heat and mass transfer during the conductive heating of a coal particle. We have established the boundary conditions of combustion initiation, and the conditions of thermal decomposition and solid fuel particles decay, characterized by the temperature of a heat source, and the duration of the respective stages.

  5. Reconstruction of 3D Micro Pore Structure of Coal and Simulation of Its Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Guang-zhe Deng

    2017-01-01

    Full Text Available This article takes the low permeability coal seam in the coalfield of South Judger Basin in Xinjiang, as a research object. The pore structure characteristics of coal rock mass in low permeability coal seam were analyzed quantitatively using scanning electron microscopy (SEM through the methods of statistics and digital image analysis. Based on the pore structure parameters and the distribution function of the coal rock mass, a three-dimensional porous cylinder model with different porosity was reconstructed by FLAC3D. The numerical simulation study of reconstructed pore model shows that (1 the porosity and the compressive strength have obvious nonlinear relation and satisfy the negative exponential relation; (2 the porosity significantly affects the stress distribution; with the increase of micro porosity, the stress distribution becomes nonuniform; (3 the compressive failures of different models are mainly shear failures, and the shape of fracture section is related to porosity; (4 the variation of seepage coefficient of the pore reconstruction model is consistent with the development of micro cracks. The micro mechanism of the deformation and failure of coal and the interaction of multiphase flow with porosity are revealed, which provides a theoretical reference for the clean development of the low permeability coal seam.

  6. Sampling and sample handling procedures for priority pollutants in surface coal mining wastewaters. [Detailed list to be analyzed for

    Energy Technology Data Exchange (ETDEWEB)

    Hayden, R. S.; Johnson, D. O.; Henricks, J. D.

    1979-03-01

    The report describes the procedures used by Argonne National Laboratory to sample surface coal mine effluents in order to obtain field and laboratory data on 110 organic compounds or classes of compounds and 14 metals and minerals that are known as priority pollutants, plus 5-day biochemical oxygen demand (BOD/sub 5/), total organic carbon (TOC), chemical oxygen demand (COD), total dissolved solids (TDS), and total suspended solids (TSS). Included are directions for preparation of sampling containers and equipment, methods of sampling and sample preservation, and field and laboratory protocols, including chain-of-custody procedures. Actual analytical procedures are not described, but their sources are referenced.

  7. Considerations for modeling small-particulate impacts from surface coal-mining operations based on wind-tunnel simulations

    Energy Technology Data Exchange (ETDEWEB)

    Perry, S.G.; Petersen, W.B. [Air Resources Lab., Research Triangle Park, NC (United States); Thompson, R.S. [Atmospheric Research and Exposure Assessment Lab., Research Triangle Park, NC (United States)

    1994-12-31

    The Clean Air Act Amendments of 1990 provide for a reexamination of the current Environmental Protection Agency`s (USEPA) methods for modeling fugitive particulate (PM10) from open-pit, surface coal mines. The Industrial Source Complex Model (ISCST2) is specifically named as the method that needs further study. Title II, Part B, Section 234 of the Amendments states that {open_quotes}...the Administrator shall analyze the accuracy of such model and emission factors and make revisions as may be necessary to eliminate any significant over-predictions of air quality effect of fugitive particulate emissions from such sources.{close_quotes}

  8. Surface elastic properties in silicon nanoparticles

    Science.gov (United States)

    Melis, Claudio; Giordano, Stefano; Colombo, Luciano

    2017-09-01

    The elastic behavior of the external surface of a solid body plays a key role in nanomechanical phenomena. While bulk elasticity enjoys the benefits of a robust theoretical understanding, many surface elasticity features remain unexplored: some of them are here addressed by blending together continuum elasticity and atomistic simulations. A suitable readdressing of the surface elasticity theory allows to write the balance equations in arbitrary curvilinear coordinates and to investigate the dependence of the surface elastic parameters on the mean and Gaussian curvatures of the surface. In particular, we predict the radial strain induced by surface effects in spherical and cylindrical silicon nanoparticles and provide evidence that the surface parameters are nearly independent of curvatures and, therefore, of the surface conformation.

  9. Engineering properties of lightweight geopolymer synthesized from coal bottom ash and rice husk ash

    Science.gov (United States)

    Thang, Nguyen Hoc; Hoa, Nguyen Ngoc; Quyen, Pham Vo Thi Ha; Tuyen, Nguyen Ngoc Kim; Anh, Tran Vu Thao; Kien, Pham Trung

    2018-04-01

    Geopolymer technology was developed by Joseph Davidovits in 1970s based on reactions among alumino-silicate resources in high alkaline conditions. Geopolymer has been recently gaining attention as an alternative binder for Ordinary Portland cement (OPC) due to its low energy and CO2 burden. The raw materials used for geopolymerization normally contain high SiO2 and Al2O3 in the chemical compositions such as meta-kaoline, rice husk ash, fly ash, bottom ash, blast furnace slag, red mud, and others. Moreover, in this paper, coal bottom ash (CBA) and rice husk ash (RHA), which are industrial and agricultural wastes, respectively, were used as raw materials with high alumino-silicate resources. Both CBA and RHA were mixed with sodium hydroxide (NaOH) solution for 20 minutes to obtain the geopolymer pastes. The pastes were filled in 5-cm cube molds according to ASTM C109/C109M 99, and then cured at room condition for hardening of the geopolymer specimens. After 24 hours, the specimens were removed out of the molds and continuously cured at room condition for 27 days. The geopolymer-based materials were then tested for engineering properties such as compressive strength (MPa), volumetric weight (kg/m3), and water absorption (kg/m3). Results indicated that the material can be considered lightweight with volumetric weight from 1192 to 1425 kg/m3; compressive strength at 28 days is in the range of 12.38 to 37.41 MPa; and water absorption is under 189.92 kg/m3.

  10. Thermodynamic properties calculation of the flue gas based on its composition estimation for coal-fired power plants

    International Nuclear Information System (INIS)

    Xu, Liang; Yuan, Jingqi

    2015-01-01

    Thermodynamic properties of the working fluid and the flue gas play an important role in the thermodynamic calculation for the boiler design and the operational optimization in power plants. In this study, a generic approach to online calculate the thermodynamic properties of the flue gas is proposed based on its composition estimation. It covers the full operation scope of the flue gas, including the two-phase state when the temperature becomes lower than the dew point. The composition of the flue gas is online estimated based on the routinely offline assays of the coal samples and the online measured oxygen mole fraction in the flue gas. The relative error of the proposed approach is found less than 1% when the standard data set of the dry and humid air and the typical flue gas is used for validation. Also, the sensitivity analysis of the individual component and the influence of the measurement error of the oxygen mole fraction on the thermodynamic properties of the flue gas are presented. - Highlights: • Flue gas thermodynamic properties in coal-fired power plants are online calculated. • Flue gas composition is online estimated using the measured oxygen mole fraction. • The proposed approach covers full operation scope, including two-phase flue gas. • Component sensitivity to the thermodynamic properties of flue gas is presented.

  11. Coal refuse reclamation project

    Energy Technology Data Exchange (ETDEWEB)

    Zellmer, S.D.

    1979-04-06

    A 13.8 ha abandoned coal refuse site in southwestern Illinois was reclaimed by recontouring the refuse material and covering it with a minimum 30 cm of soil. The reclamation procedure included determination of the site's final land use, collection of preconstruction environmental data, and development and implementation of engineering plans. The project is demonstrating methods that can be used to reclaim abandoned coal refuse sites, and a multidisciplinary approach is being used to evaluate postconstruction environmental and economic effects of the reclamation effort. Surface water quality has shown significant improvement and plant cover is becoming established on the site. Soil microbial populations are developing and wildlife habitats are forming. The economic value of the site and adjacent properties has increased substantially and the area's aesthetic value has been enhanced. This project is providing valuable design data for future reclamation efforts of this type.

  12. Efficient and large scale synthesis of graphene from coal and its film electrical properties studies.

    Science.gov (United States)

    Wu, Yingpeng; Ma, Yanfeng; Wang, Yan; Huang, Lu; Li, Na; Zhang, Tengfei; Zhang, Yi; Wan, Xiangjian; Huang, Yi; Chen, Yongsheng

    2013-02-01

    Coal, which is abundant and has an incompact structure, is a good candidate to replace graphite as the raw material for the production of graphene. Here, a new solution phase technique for the preparation of graphene from coal has been developed. The precursor: graphene oxide got from coal was examined by atomic force microscopy, dynamic light scattering and X-ray diffraction, the results showed the GO was a small and single layer sheet. The graphene was examined by X-ray photoelectron spectroscopy, and Raman spectroscopy. Furthermore, graphene films have been prepared using direct solution process and the electrical conductivity and Hall effect have been studied. The results showed the conductivity of the films could reach as high as 2.5 x 10(5) Sm(-1) and exhibited an n-type behavior.

  13. Thermophysical properties of composite fuel based on T grade coal (Alardinskoe deposit) and timber industry wastes

    Science.gov (United States)

    Yankovsky, S. A.; Tolokolnikov, A. A.; Gubin, V. E.; Slyusarskiy, K. V.; Zenkov, A. V.

    2017-09-01

    Results of experimental studies of composite fuel thermal decomposition processes based on T grade coal (Alardinskoe deposit) and timber industry wastes (fine wood) are presented. C, H, N, S weight percentage of each component of composite fuel was determined experimentally. It has been established that with an increase in wood concentration up to 50% in composite fuel, its energy characteristics decrease by less than 3.6%, while the yield of fly ash is 39.7%. An effective composite fuel composition has been defined as 50%/50%. Results of performed experimental studies suggest that it is possible to use composite fuels based on coal and wood at thermal power plants.

  14. Laser modification of macroscopic properties of metal surface layer

    Science.gov (United States)

    Kostrubiec, Franciszek

    1995-03-01

    Surface laser treatment of metals comprises a number of diversified technological operations out of which the following can be considered the most common: oxidation and rendering surfaces amorphous, surface hardening of steel, modification of selected physical properties of metal surface layers. In the paper basic results of laser treatment of a group of metals used as base materials for electric contacts have been presented. The aim of the study was to test the usability of laser treatment from the viewpoint of requirements imposed on materials for electric contacts. The results presented in the paper refer to two different surface treatment technologies: (1) modification of infusible metal surface layer: tungsten and molybdenum through laser fusing of their surface layer and its crystallization, and (2) modification of surface layer properties of other metals through laser doping of their surface layer with foreign elements. In the paper a number of results of experimental investigations obtained by the team under the author's supervision are presented.

  15. Probing Anisotropic Surface Properties of Molybdenite by Direct Force Measurements.

    Science.gov (United States)

    Lu, Zhenzhen; Liu, Qingxia; Xu, Zhenghe; Zeng, Hongbo

    2015-10-27

    Probing anisotropic surface properties of layer-type mineral is fundamentally important in understanding its surface charge and wettability for a variety of applications. In this study, the surface properties of the face and the edge surfaces of natural molybdenite (MoS2) were investigated by direct surface force measurements using atomic force microscope (AFM). The interaction forces between the AFM tip (Si3N4) and face or edge surface of molybdenite were measured in 10 mM NaCl solutions at various pHs. The force profiles were well-fitted with classical DLVO (Derjaguin-Landau-Verwey-Overbeek) theory to determine the surface potentials of the face and the edge surfaces of molybdenite. The surface potentials of both the face and edge surfaces become more negative with increasing pH. At neutral and alkaline conditions, the edge surface exhibits more negative surface potential than the face surface, which is possibly due to molybdate and hydromolybdate ions on the edge surface. The point of zero charge (PZC) of the edge surface was determined around pH 3 while PZC of the face surface was not observed in the range of pH 3-11. The interaction forces between octadecyltrichlorosilane-treated AFM tip (OTS-tip) and face or edge surface of molybdenite were also measured at various pHs to study the wettability of molybdenite surfaces. An attractive force between the OTS-tip and the face surface was detected. The force profiles were well-fitted by considering DLVO forces and additional hydrophobic force. Our results suggest the hydrophobic feature of the face surface of molybdenite. In contrast, no attractive force between the OTS-tip and the edge surface was detected. This is the first study in directly measuring surface charge and wettability of the pristine face and edge surfaces of molybdenite through surface force measurements.

  16. SURFACE PROPERTIES AND CATALYTIC PERFORMANCE OF Pt ...

    African Journals Online (AJOL)

    various temperatures of precipitates obtained from aqueous solutions in the ... The oxidation reactivity of VOCs is in the following order: alcohols > aldheydes > aromatics ... Specific surface areas (SSA) were calculated by the BET method from ...

  17. Electrochemical Properties of Alkanethiol Monolayers Adsorbed on Nanoporous Au Surfaces

    International Nuclear Information System (INIS)

    Chu, Yeon Yi; Seo, Bora; Kim, Jong Won

    2010-01-01

    We investigated the electrochemical properties of alkanethiol monolayers adsorbed on NPG surfaces by cyclic voltammetry and electrochemical impedance spectroscopy, and the results are compared to those on flat Au surfaces. The reductive desorption of alkanethiols on NPG surfaces is observed in more negative potential regions than that on flat Au surfaces due the stronger S-Au interaction on NPG surfaces. While the electron transfer through alkanethiol monolayers on flat Au surfaces occurs via a tunneling process through the monolayer films, the redox species can permeate through the monolayers on NPG surfaces to transfer the electrons to the Au surfaces. The results presented here will help to elucidate the intrinsic electrochemical properties of alkanethiol monolayers adsorbed on curved Au surfaces, particularly on the surface of AuNPs. Self-assembled monolayers (SAMs) of thiolate molecules on Au surfaces have been the subject of intensive research for the last few decades due to their unique physical and chemical properties. The well-organized surface structures of thiolate SAMs with various end-group functionalities can be further utilized for many applications in biology and nanotechnology. In addition to the practical applications, SAMs of thiolate molecules on Au surfaces also provide unique opportunities to address fundamental issues in surface chemistry such as self-organized surface structures, electron transfer behaviors, and moleculesubstrate interactions. Although there have been numerous reports on the fundamental physical and chemical properties of thiolate SAMs on Au surfaces, most of them were investigated on flat Au surfaces, typically on well-defined Au(111) surfaces

  18. Antifouling polymer brushes displaying antithrombogenic surface properties

    Czech Academy of Sciences Publication Activity Database

    de los Santos Pereira, Andres; Sheikh, S.; Blaszykowski, C.; Pop-Georgievski, Ognen; Fedorov, K.; Thompson, M.; Rodriguez-Emmenegger, Cesar

    2016-01-01

    Roč. 17, č. 3 (2016), s. 1179-1185 ISSN 1525-7797 R&D Projects: GA ČR(CZ) GJ15-09368Y; GA MŠk(CZ) ED1.1.00/02.0109 Grant - others:OPPK(XE) CZ.2.16/3.1.00/21545 Program:OPPK Institutional support: RVO:61389013 Keywords : polymer brushes * surface characterization * antifouling surfaces Subject RIV: BO - Biophysics Impact factor: 5.246, year: 2016

  19. Water resources and effects of potential surface coal mining on dissolved solids in Hanging Woman Creek basin, southeastern Montana

    Science.gov (United States)

    Cannon, M.R.

    1989-01-01

    Groundwater resources of the Hanging Woman Creek basin, Montana include Holocene and Pleistocene alluvial aquifers and sandstone , coal, and clinker aquifers in the Paleocene Fort Union Formation. Surface water resources are composed of Hanging Woman Creek, its tributaries, and small stock ponds. Dissolved-solids concentrations in groundwater ranged from 200 to 11,00 mg/L. Generally, concentrations were largest in alluvial aquifers and smallest in clinker aquifers. Near its mouth, Hanging Woman Creek had a median concentration of about 1,800 mg/L. Mining of the 20-foot to 35-foot-thick Anderson coal bed and 3-foot to 16-foot thick Dietz coal bed could increase dissolved-solids concentrations in shallow aquifers and in Hanging Woman Creek because of leaching of soluble minerals from mine spoils. Analysis of saturated-paste extracts from 158 overburden samples indicated that water moving through mine spoils would have a median increase in dissolved-solids concentration of about 3,700 mg/L, resulting in an additional dissolved-solids load to Hanging Woman Creek of about 3.0 tons/day. Hanging Woman Creek near Birney could have an annual post-mining dissolved-solids load of 3,415 tons at median discharge, a 47% increase from pre-mining conditions load. Post-mining concentrations of dissolved solids, at median discharge, could range from 2,380 mg/L in March to 3,940 mg/L in August, compared to mean pre-mining concentrations that ranged from 1,700 mg/L in July, November, and December to 2,060 mg/L in May. Post-mining concentrations and loads in Hanging Woman Creek would be smaller if a smaller area were mined. (USGS)

  20. Studies of coal slurries property; Slurry no seijo ni kansuru kento

    Energy Technology Data Exchange (ETDEWEB)

    Kawabata, M.; Aihara, Y.; Imada, K. [Nippon Steel Corp., Tokyo (Japan); Nogami, Y.; Inokuchi, K. [Mitsui SRC Development Co. Ltd., Tokyo (Japan); Sakaki, T.; Shibata, M.; Hirosue, H. [Kyushu National Industrial Research Institute, Saga (Japan)

    1996-10-28

    It was previously found that the increase of slurry temperature provides a significant effect of slurry viscosity reduction for the coal slurry with high concentration of 50 wt%. To investigate the detailed influence of slurry temperature for the coal slurry with concentration of 50 wt%, influence of temperature on the successive change of apparent viscosity was observed at the constant shear rate. When the concentration of coal was increased from 45 wt% to 50 wt%, viscosity of the slurry was rapidly increased. When heated above 70{degree}C, the apparent viscosity decreased during heating to the given temperature, but it increased successively after reaching to the given temperature. The apparent viscosity showed higher value than that of the initial viscosity. The coal slurry with concentration of 50 wt% showed the fluidity of Newtonian fluid at the lower shear rate region, but showed the fluidity of pseudo-plastic fluid at the higher shear rate region. The slurry having high apparent viscosity by the successive change showed higher apparent viscosity with increasing the higher even by changing the shear rate. 1 ref., 4 figs.

  1. A Comprehensive Review on the Properties of Coal Bottom Ash in Concrete as Sound Absorption Material

    Directory of Open Access Journals (Sweden)

    Ramzi Hannan Nurul Izzati Raihan

    2017-01-01

    Full Text Available The government is currently implementing policies to increase the usage of coal as fuel for electricity generation. At the same time, the dependency on gas will be reduced. In addition, coal power plants in Malaysia produce large amounts of industrial waste such as bottom ash which is collected in impoundment ponds (ash pond. However, millions of tons of coal ash (bottom ash waste are collected in ponds near power plant stations. Since bottom ash has been classified as hazardous material that threatens the health and safety of human life, an innovative and sustainable solution has been introduced to reuse or recycle industrial waste such as coal bottom ash in concrete mixtures to create a greener and more sustainable world. Bottom ash has the potential to be used as concrete material to replace fine aggregates, coarse aggregates or both. Hence, this paper provides an overview of previous research which used bottom ash as fine aggregate replacement in conventional concrete. The workability, compressive strength, flexural strength, and sound absorption of bottom ash in concrete are reviewed.

  2. Landscape management in an area affected by surface brown coal mining

    Science.gov (United States)

    Vráblíková, J.; Wildová, E.; Vráblík, P.; Blažková, M.

    2017-10-01

    The contribution summarizes results of a project concentrated on landscape management of an area affected by brown coal mining located in northern Bohemia (The Most basin) focusing on restoration and reclamation processes. It describes in particular the shares of individual types of reclamations in the area of interest. A strategic document that also supports landscape restoration in anthropogenically burdened regions was written within the project called “Restart” and the second part of the contribution is focused on its chapters which address this issue.

  3. Development and Application of Blast Casting Technique in Large-Scale Surface Mines: A Case Study of Heidaigou Surface Coal Mine in China

    Directory of Open Access Journals (Sweden)

    Li Ma

    2016-01-01

    Full Text Available Blast casting is a high-efficiency technique applied in surface mines for overburden removal and results in stripping cost savings. According to ballistic theory and center-of-mass frame basic movement principles, key factors influencing blast casting effect were analyzed, which include bench height and mining panel width, inclined angle of blast holes, explosive unit consumption (EUC, delay-time interval, presplitting, and blast hole pattern parameters. An intelligent design software was developed for obtaining better breaking and casting effect, and the error rates predicted with actual result can be controlled with 10%. Blast casting technique was successfully applied in Heidaigou Surface Coal Mine (HSCM with more than 34% of material casted into the inner dump. A ramp ditch was set within the middle inner dump for coal transportation. The procedure of stripping and excavating was implemented separately and alternately in the two sections around the middle ramp ditch. An unconstrained-nonlinear model was deduced for optimizing the shift distance of the middle ramp. The calculation results show that optimum shift distance of HSCM is 480 m, and the middle ditch should be shifted after 6 blast casting mining panels being stripped.

  4. Tuning antimicrobial properties of biomimetic nanopatterned surfaces.

    Science.gov (United States)

    Michalska, Martyna; Gambacorta, Francesca; Divan, Ralu; Aranson, Igor S; Sokolov, Andrey; Noirot, Philippe; Laible, Philip D

    2018-04-05

    Nature has amassed an impressive array of structures that afford protection from microbial colonization/infection when displayed on the exterior surfaces of organisms. Here, controlled variation of the features of mimetics derived from etched silicon allows for tuning of their antimicrobial efficacy. Materials with nanopillars up to 7 μm in length are extremely effective against a wide range of microbial species and exceed the performance of natural surfaces; in contrast, materials with shorter/blunter nanopillars (<2 μm) selectively killed specific species. Using a combination of microscopies, the mechanisms by which bacteria are killed are demonstrated, emphasizing the dependence upon pillar density and tip geometry. Additionally, real-time imaging reveals how cells are immobilized and killed rapidly. Generic or selective protection from microbial colonization could be conferred to surfaces [for, e.g., internal medicine, implants (joint, dental, and cosmetic), food preparation, and the agricultural industry] patterned with these materials as coatings.

  5. Manganese phospate physical chemistry and surface properties

    International Nuclear Information System (INIS)

    Najera R, N.; Romero G, E. T.

    2008-01-01

    This paper presents the methodology for the manganese phosphate (III) synthesis (MnP0 4 H 2 0) from manganese chloride. The physicochemical characterization was carried out by: X-ray diffraction, scanning electron microscopy, infrared analysis and thermal gravimetric analysis. The surface characterization is obtained through the determination of surface area, point of zero charge and kinetics of moisture. As a phosphate compound of a metal with low oxidation state is a promising compound for removal pollutants from water and soil, can be used for the potential construction of containment barriers for radioactive wastes. (Author)

  6. Composition and physical properties of Enceladus' surface

    Science.gov (United States)

    Brown, R.H.; Clark, R.N.; Buratti, B.J.; Cruikshank, D.P.; Barnes, J.W.; Mastrapa, R.M.E.; Bauer, J.; Newman, S.; Momary, T.; Baines, K.H.; Bellucci, G.; Capaccioni, F.; Cerroni, P.; Combes, M.; Coradini, A.; Drossart, P.; Formisano, V.; Jaumann, R.; Langavin, Y.; Matson, D.L.; McCord, T.B.; Nelson, R.M.; Nicholson, P.D.; Sicardy, B.; Sotin, Christophe

    2006-01-01

    Observations of Saturn's satellite Enceladus using Cassini's Visual and Infrared Mapping Spectrometer instrument were obtained during three flybys of Enceladus in 2005. Enceladus' surface is composed mostly of nearly pure water ice except near its south pole, where there are light organics, CO2, and amorphous and crystalline water ice, particularly in the region dubbed the "tiger stripes." An upper limit of 5 precipitable nanometers is derived for CO in the atmospheric column above Enceladus, and 2% for NH 3 in global surface deposits. Upper limits of 140 kelvin (for a filled pixel) are derived for the temperatures in the tiger stripes.

  7. Structural and electronic properties of hydrosilylated silicon surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Baumer, A.

    2005-11-15

    The structural and electronic properties of alkyl-terminated Si surfaces prepared by thermallyinduced hydrosilylation have been studied in detail in the preceding chapters. Various surfaces have been used for the functionalization ranging from crystalline Si over amorphous hydrogenated Si to nanoscaled materials such as Si nanowires and nanoparticles. In each case, the alkyl-terminated surfaces have been compared to the native oxidized and H-terminated surfaces. (orig.)

  8. Surface properties of semi-infinite Fermi systems

    International Nuclear Information System (INIS)

    Campi, X.; Stringari, S.

    1979-10-01

    A functional relation between the kinetic energy density and the total density is used to analyse the surface properties of semi-infinite Fermi systems. One find an explicit expression for the surface thickness in which the role of the infinite matter compressibility, binding energy and non-locality effects is clearly shown. The method, which holds both for nuclear and electronic systems (liquid metals), yields a very simple relation between the surface thickness and the surface energy

  9. Adsorption Properties of the Cu(115) Surface

    DEFF Research Database (Denmark)

    Godowski, P. J.; Groso, A.; Hoffmann, S. V.

    2010-01-01

    The interfaces: K/Cu(115) and CO/Cu(115) have been characterized using surface sensitive techniques, including low energy electron diffraction and photoelectron spectroscopy. K adatoms show tendency to occupy the sites close to the step edges. At low temperature (near 125 K), after completion of ...

  10. Wetting Properties of Molecularly Rough Surfaces

    Czech Academy of Sciences Publication Activity Database

    Svoboda, Martin; Malijevský, Alexandr; Lísal, Martin

    2015-01-01

    Roč. 143, č. 10 (2015), s. 104701 ISSN 0021-9606 R&D Projects: GA ČR GA13-09914S; GA MŠk LH12020 Institutional support: RVO:67985858 Keywords : contant-angle * solid-surface * dynamics Subject RIV: BJ - Thermodynamics Impact factor: 2.894, year: 2015

  11. Improving soil enzyme activities and related quality properties of reclaimed soil by applying weathered coal in opencast-mining areas of the Chinese loess plateau

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hua [College of Environment and Resources, Shanxi University, Taiyuan (China); CAS/Shandong Provincial Key Laboratory of Coastal Environmental Process, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences (CAS), Yantai (China); Shao, Hongbo [CAS/Shandong Provincial Key Laboratory of Coastal Environmental Process, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences (CAS), Yantai (China); Institute for Life Sciences, Qingdao University of Science and Technology (QUST), Qingdao (China); Li, Weixiang; Bi, Rutian [Shanxi Agricultural University, Taigu (China); Bai, Zhongke [Department of Land Science Technology, University of Geosciences, Beijing (China)

    2012-03-15

    There are many problems for the reclaimed soil in opencast-mining areas of the Loess Plateau of China such as poor soil structure and extreme poverty in soil nutrients and so on. For the sake of finding a better way to improve soil quality, the current study was to apply the weathered coal for repairing soil media and investigate the physicochemical properties of the reclaimed soil and the changes in enzyme activities after planting Robinia pseucdoacacia. The results showed that the application of the weathered coal significantly improved the quality of soil aggregates, increased the content of water stable aggregates, and the organic matter, humus, and the cation exchange capacity of topsoil were significantly improved, but it did not have a significant effect on soil pH. Planting R. pseucdoacacia significantly enhanced the activities of soil catalase, urease, and invertase, but the application of the weathered coal inhibited the activity of catalase. Although the application of appropriate weathered coal was able to significantly increase urease activity, the activities of catalase, urease, or invertase had a close link with the soil profile levels and time. This study suggests that applying weathered coals could improve the physicochemical properties and soil enzyme activities of the reclaimed soil in opencast-mining areas of the Loess Plateau of China and the optimum applied amount of the weathered coal for reclaimed soil remediation is about 27 000 kg hm{sup -2}. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. Properties, origin and nomenclature of rodlets of the inertinite maceral group in coals of the central Appalachian basin, U.S.A.

    Science.gov (United States)

    Lyons, P.C.; Finkelman, R.B.; Thompson, C.L.; Brown, F.W.; Hatcher, P.G.

    1982-01-01

    Resin rodlets, sclerenchyma strands and woody splinters, which are collectively called rodlets, were studied by chemical, optical petrographic, and scanning-electron microscopic (SEM) techniques. A study was made of such rodlets from the bituminous coal beds of the central Appalachian basin (Pennsylvanian; Upper Carboniferous) of the United States. Comparisons were made with rodlets from coal beds of the Illinois basin, the Southern Anthracite Field of Pennsylvania, the St. Rose coal field of Nova Scotia, and European and other coal fields. In order to determine their physical and chemical properties, a detailed study was made of the rodlets from the Pomeroy coal bed (high volatile A bituminous coal; Monongahela Formation; Upper Pennsylvanian) of Kanawha County, West Virginia. The origin of the rodlets was determined by a comparative analysis of a medullosan (seed fern) stem from the Herrin (No. 6) coal bed (high volatile C bituminous coal; Carbondale Formation) from Washington County, Illinois. Rodlets are commonly concentrated in fusain or carbominerite layers or lenses in bituminous coal beds of the central Appalachian basin. Most of the rodlets examined in our study were probably derived from medullosan seed ferns. The three types of rodlets are distinguished on the basis of cellularity, morphology and fracture. The resin rodlets studied by us are noncellular and appear to be similar in properties and origin to those found in coal beds of the Middle and Upper Pennsylvanian of the Illinois basin. The resin rodlets extracted from the Pomeroy coal bed exhibit high relief and high reflectance when polished and viewed in reflected light; they are opaque in transmitted light. In cross section, the resin rodlets are oval to round and have diameters ranging from 60 to 450 ??m. Many are solid, but some have vesicles, canals or cavities, which are commonly filled with clay, probably kaolinite. Typically, they have distinct fracture patterns ("kerfs") in longitudinal and

  13. Sputtering properties of tungsten 'fuzzy' surfaces

    International Nuclear Information System (INIS)

    Nishijima, D.; Baldwin, M.J.; Doerner, R.P.; Yu, J.H.

    2011-01-01

    Sputtering yields of He-induced W 'fuzzy' surfaces bombarded by Ar have been measured in the linear divertor plasma simulator PISCES-B. It is found that the sputtering yield of a fuzzy surface, Y fuzzy , decreases with increasing fuzzy layer thickness, L, and saturates at ∼10% of that of a smooth surface, Y smooth , at L > 1 μm. The reduction in the sputtering yield is suspected to be due mainly to the porous structure of fuzz, since the ratio, Y fuzzy /Y smooth follows (1 - p fuzz ), where p fuzz is the fuzz porosity. Further, Y fuzzy /Y smooth is observed to increase with incident ion energy, E i . This may be explained by an energy dependent change in the angular distribution of sputtered W atoms, since at lower E i , the angular distribution is observed to become more butterfly-shaped. That is, a larger fraction of sputtered W atoms can line-of-sight deposit/stick onto neighboring fuzz nanostructures for lower E i butterfly distributions, resulting in lower ratio of Y fuzzy /Y smooth .

  14. Cuttability of coal

    Energy Technology Data Exchange (ETDEWEB)

    Sikora, W

    1978-01-01

    The process of cutting dull M, dull bright MB, bright dull BM, and bright B coal under various compressive stress conditions was studied in laboratory tests. The efficiency of ploughs depends much more on the natural mining conditions than does that of shearer-loaders. For seams of medium workability, it is difficult to forecast whether ploughs will be successful. Cuttability tests are a good way of determining whether ploughs can be used. The effort necessary to cut coal in a stressed condition depends not only on such properties as the workability defined by the Protodyakonov index or compressive strength, but also, and mainly, on the petrographic structure and elastic properties of the coal. In bright coals with high elastic strain, and with BM and MB coals, a much greater increment of effort is necessary with increase in compressive stresses. The cuttability of dull coals from difficult mines was not very different.

  15. Bioregional Assessments: Determining the Impacts of Coal Resource Development on Water Resources in Australia through Groundwater, Surface Water and Ecological Modelling

    Science.gov (United States)

    Peeters, L. J.; Post, D. A.; Crosbie, R.; Holland, K.

    2017-12-01

    While extraction of methane from shale gas deposits has been the principal source of the recent expansion of the industry in the United States, in Australia extraction of methane from coal bed methane deposits (termed `coal seam gas' in Australia) has been the focus to date. The two sources of methane share many of the same characteristics including the potential requirement for hydraulic fracturing. However, as coal seam gas deposits generally occur at shallower depths than shale gas, the potential impacts of extraction on surface and groundwater resources may be of even greater concern. The Australian Federal Government commissioned a multi-disciplinary programme of bioregional assessments to improve understanding of the potential impacts of coal seam gas and large coal mining activities on water resources and water-dependent assets across six bioregions Australia. A bioregional assessment is a transparent scientific analysis of the ecology, hydrology, geology and hydrogeology of a bioregion with explicit assessment of the potential direct, indirect and cumulative impacts of coal seam gas and large coal mining development on water resources. The first step in the analysis is to establish the most likely scenario for coal development in each region and establish a causal pathway linking coal development to impacts to the social, economic and ecological functioning of water resources. This forms the basis for a sequence of probabilistic geological, hydrogeological, hydrological and ecological models to quantify the probability of potential impacts. This suite of models is developed independent of the proponents and regulators of coal resource developments and so can provide unbiased information to all stakeholders. To demonstrate transparency of the modelling, all inputs, outputs and executables will be available from http://www.bioregionalassessments.gov.au. The analysis delineated a zone of potential hydrological change for each region, outside of which impacts

  16. Low temperature self-cleaning properties of superhydrophobic surfaces

    Science.gov (United States)

    Wang, Fajun; Shen, Taohua; Li, Changquan; Li, Wen; Yan, Guilong

    2014-10-01

    Outdoor surfaces are usually dirty surfaces. Ice accretion on outdoor surfaces could lead to serious accidents. In the present work, the superhydrophobic surface based on 1H, 1H, 2H, 2H-Perfluorodecanethiol (PFDT) modified Ag/PDMS composite was prepared to investigate the anti-icing property and self-cleaning property at temperatures below freezing point. The superhydrophobic surface was deliberately polluted with activated carbon before testing. It was observed that water droplet picked up dusts on the cold superhydrophobic surface and took it away without freezing at a measuring temperature of -10 °C. While on a smooth PFDT surface and a rough surface base on Ag/PDMS composite without PFDT modification, water droplets accumulated and then froze quickly at the same temperature. However, at even lower temperature of -12 °C, the superhydrophobic surface could not prevent the surface water from icing. In addition, it was observed that the frost layer condensed from the moisture pay an important role in determining the low temperature self-cleaning properties of a superhydrophobic surface.

  17. Surface morphology, structural and electrical properties of RF ...

    Indian Academy of Sciences (India)

    5

    electrical properties of RF sputtered ITO thin films deposited onto Si(100). .... scanning electron microscopy (SEM) surface images are shown along with the cross- ..... annealing effect”, J. of Alloys and Compounds 509, (2011) 6072-6076.

  18. Pseudopotentials for calculating the bulk and surface properties of solids

    International Nuclear Information System (INIS)

    Cohen, M.L.

    1983-01-01

    A survey is presented describing research in condensed matter physics using pseudopotentials to calculate electronic, structural, and vibrational properties of solids. Semiconductors are emphasized, and both bulk and surface calculations are discussed. (author) [pt

  19. Ergonomics - Using Ergonomics to Enhance Safe Production at a Surface Coal Mine - A Case Study with Powder Crews

    Energy Technology Data Exchange (ETDEWEB)

    Torma-Krajewski, J.; Wiehagen, W.; Etcheverry, A.; Turin, F.; Unger, R. [Colorado School of Mines, Golden, CO (United States)

    2009-07-01

    Job tasks that involve exposure to work-related musculoskeletal disorder (WMSD) risk factors may impact both the risk of injury and production downtime. Common WMSD risks factors associated with mining tasks include forceful exertions, awkward postures, repetitive motion, jolting and jarring, forceful gripping, contact stress, and whole body and segmental vibration. Mining environments that expose workers to temperature/humidity extremes, windy conditions, and slippery and uneven walking surfaces also contribute to injury risk. National Institute for Occupational Safety and Health (NIOSH) researchers worked with powder crew members from the Bridger Coal Company to identify and rank routine work tasks based on perceived exposure to WMSD risk factors. This article presents the process followed to identify tasks that workers believed involved the greatest exposure to risk factors and discusses risk reduction strategies. Specifically, the proposed prill truck design changes addressed cab ingress/egress, loading blast holes, and access to the upper deck of the prill truck.

  20. The political economy of regulation: Investigation of the relationship between design and performance standards in surface coal mining

    International Nuclear Information System (INIS)

    Walker, K.R.

    1991-01-01

    Research concerning political and economic regulatory policy was conducted on 15 randomly selected surface coal mines in Tennessee. Data on violations were collected over a 6-year period from 1979 through 1984. The primary purpose of this study was to investigate the approaches of the Carter and Reagan administrations concerning the implementation of design and performance regulations of Public Law 95-87. The study concluded that: (1) A change in political administration affects regulatory policy concerning enforcement practices. (2) Regulatory policy is altered in the direction of economic activity believed by an administration to be desirable to society and its constituents. (3) Elaborate rule making activity constrains market activity. (4) The coupling of design and performance standards should be retained. No difference was found in the number of violations for design and associated performance standards. Findings support the theory that it is the administration that affects change in regulatory policy, and not the regulatory construct for compliance with a mandate

  1. Surface chemical characteristics of coal fly ash particles after interaction with seawater under natural deep sea conditions

    International Nuclear Information System (INIS)

    Brami, Y.; Shemesh, A.; Cohen, H.; Herut, B.

    1999-01-01

    The surface chemical characteristics of coal fly ash (CFA) before and after interaction with Mediterranean deep seawater was studied by X-ray photoelectron spectroscopy (XPS). Significantly lower values of Si, Ca, and S and higher values of Mg and Cl were found in the retrieved CFA as compared to fresh CFA. It is suggested that hydrolysis of the oxide matrixes results in an alkaline environment which rapidly leads to several chemical reactions. The two most important are (a) dissolution of the amorphous silicate and the calcium phases and (b) precipitation of Mg(OH) 2 -brucite. A depth profile of the retrieved CFA was measured by both line-shape analysis of the XPS spectra and by consecutive cycle of sputtering. The thickness of the brucite layer is estimated to be 1.3 nm

  2. Influence of surface flattening on biodiversity of terrestrial arthropods during early stages of brown coal spoil heap restoration.

    Science.gov (United States)

    Moradi, Jabbar; Potocký, Pavel; Kočárek, Petr; Bartuška, Martin; Tajovský, Karel; Tichánek, Filip; Frouz, Jan; Tropek, Robert

    2018-08-15

    Heterogeneity of environmental conditions is the crucial factor supporting biodiversity in various habitats, including post-mining sites. The effects of micro-topographic heterogeneity on biodiversity and conservation potential of arthropod communities in post-industrial habitats had not been studied before now. At one of the largest European brown coal spoil heaps, we sampled eight groups of terrestrial arthropods with different life strategies (moths, spiders, ground beetles, ants, orthopteroids, centipedes, millipedes, and woodlice), in successionally young plots (5-18 y), with a heterogeneous wavy surface after heaping, and compared the communities with plots flattened by dozing. A combination of the standardized quantitative sampling, using two different methods, and a paired design of the plot selection enabled a robust analysis. Altogether, we recorded 380 species of the focal arthropods, 15 of them nationally threatened. We revealed the importance of the micro-topographic heterogeneity for the formation of the biodiversity of arthropods in their secondary refuges. The communities with higher biodiversity and conservation value were detected in the plots with heterogeneous surfaces; exceptions were ground beetles and millipedes. The surface flattening, often the first step of technical reclamation projects, thus suppress biodiversity of most terrestrial arthropods during the restoration of post-mining sites. Since the communities of both surface types differed, the proportional presence on both surfaces could be more efficient in supporting the local biodiversity. We suggest reducing the surface dozing for the cases with other concerns only, to achieve a proportional representation of both surface types. Such a combination of different restoration approaches would, thus, efficiently support high biodiversity of groups with various needs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Determining the hydraulic and fracture properties of the Coal Seam Gas well by numerical modelling and GLUE analysis

    Science.gov (United States)

    Askarimarnani, Sara; Willgoose, Garry; Fityus, Stephen

    2017-04-01

    Coal seam gas (CSG) is a form of natural gas that occurs in some coal seams. Coal seams have natural fractures with dual-porosity systems and low permeability. In the CSG industry, hydraulic fracturing is applied to increase the permeability and extract the gas more efficiently from the coal seam. The industry claims that it can design fracking patterns. Whether this is true or not, the public (and regulators) requires assurance that once a well has been fracked that the fracking has occurred according to plan and that the fracked well is safe. Thus defensible post-fracking testing methodologies for gas generating wells are required. In 2009 a fracked well HB02, owned by AGL, near Broke, NSW, Australia was subjected to "traditional" water pump-testing as part of this assurance process. Interpretation with well Type Curves and simple single phase (i.e. only water, no gas) highlighted deficiencies in traditional water well approaches with a systemic deviation from the qualitative characteristic of well drawdown curves (e.g. concavity versus convexity of drawdown with time). Accordingly a multiphase (i.e. water and methane) model of the well was developed and compared with the observed data. This paper will discuss the results of this multiphase testing using the TOUGH2 model and its EOS7C constitutive model. A key objective was to test a methodology, based on GLUE monte-carlo calibration technique, to calibrate the characteristics of the frack using the well test drawdown curve. GLUE involves a sensitivity analysis of how changes in the fracture properties change the well hydraulics through and analysis of the drawdown curve and changes in the cone of depression. This was undertaken by changing the native coal, fracture, and gas parameters to see how changing those parameters changed the match between simulations and the observed well drawdown. Results from the GLUE analysis show how much information is contained in the well drawdown curve for estimating field scale

  4. Tailoring Silica Surface Properties by Plasma Polymerization for Elastomer Applications

    NARCIS (Netherlands)

    Tiwari, M.; Dierkes, Wilma K.; Datta, Rabin; Talma, Auke; Noordermeer, Jacobus W.M.; van Ooij, W.J.

    2009-01-01

    The surface properties of reinforcing fillers are a crucial factor for dispersion and filler–polymer interaction in rubber compounds, as they strongly influence the final vulcanized properties of the rubber article. Silica is gaining more and more importance as reinforcing filler for rubbers, as it

  5. Tailoring Silica Surface Properties by Plasma Polymerization for Elastomer Applications

    NARCIS (Netherlands)

    Tiwari, M.; Dierkes, W.K.; Datta, R.N.; Talma, A.G.; Noordermeer, J.W.M.; van Ooij, W.J.

    2011-01-01

    The surface properties of reinforcing fillers are a crucial factor for dispersion and filler–polymer interaction in rubber compounds, as they strongly influence the final vulcanized properties of the rubber article. Silica is gaining more and more importance as reinforcing filler for rubbers, as it

  6. Laser alloying of aluminium to improve surface properties - MSSA 2010

    CSIR Research Space (South Africa)

    Mabhali, Luyolo AB

    2010-07-01

    Full Text Available and microstructure of the surface without affecting the bulk properties of the material. The process involves melting the substrate surface and injecting the powder of the alloying material into the melt pool. Process parameters such as laser power, beam spot size...

  7. Surface properties and microporosity of polyhydroxybutyrate under scanning electron microscopy

    International Nuclear Information System (INIS)

    Raouf, A.A.; Samsudin, A.R.; Samian, R.; Akool, K.; Abdullah, N.

    2004-01-01

    This study was designed to investigate the surface properties especially surface porosity of polyhydroxybutyrate (PHB) using scanning electron microscopy. PHB granules were sprinkled on the double-sided sticky tape attached on a SEM aluminium stub and sputtered with gold (10nm thickness) in a Polaron SC515 Coater, following which the samples were placed into the SEM specimen chamber for viewing and recording. Scanning electron micrographs with different magnification of PHB surface revealed multiple pores with different sizes. (Author)

  8. Low temperature oxidation and spontaneous combustion characteristics of upgraded low rank coal

    Energy Technology Data Exchange (ETDEWEB)

    Choi, H.K.; Kim, S.D.; Yoo, J.H.; Chun, D.H.; Rhim, Y.J.; Lee, S.H. [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

    2013-07-01

    The low temperature oxidation and spontaneous combustion characteristics of dried coal produced from low rank coal using the upgraded brown coal (UBC) process were investigated. To this end, proximate properties, crossing-point temperature (CPT), and isothermal oxidation characteristics of the coal were analyzed. The isothermal oxidation characteristics were estimated by considering the formation rates of CO and CO{sub 2} at low temperatures. The upgraded low rank coal had higher heating values than the raw coal. It also had less susceptibility to low temperature oxidation and spontaneous combustion. This seemed to result from the coating of the asphalt on the surface of the coal, which suppressed the active functional groups from reacting with oxygen in the air. The increasing upgrading pressure negatively affected the low temperature oxidation and spontaneous combustion.

  9. Landuse change detection in a surface coal mine area using multi-temporal high resolution satellite images

    Energy Technology Data Exchange (ETDEWEB)

    Demirel, N.; Duzgun, S.; Kemal Emil, M. [Middle East Technical Univ., Ankara (Turkey). Dept. of Mining Engineering

    2010-07-01

    Changes in the landcover and landuse of a mine area can be caused by surface mining activities, exploitation of ore and stripping and dumping overburden. In order to identify the long-term impacts of mining on the environment and land cover, these changes must be continuously monitored. A facility to regularly observe the progress of surface mining and reclamation is important for effective enforcement of mining and environmental regulations. Remote sensing provides a powerful tool to obtain rigorous data and reduce the need for time-consuming and expensive field measurements. The purpose of this study was to conduct post classification change detection for identifying, quantifying, and analyzing the spatial response of landscape due to surface lignite coal mining activities in Goynuk, Bolu, Turkey, from 2004 to 2008. The paper presented the research algorithm which involved acquiring multi temporal high resolution satellite data; preprocessing the data; performing image classification using maximum likelihood classification algorithm and performing accuracy assessment on the classification results; performing post classification change detection algorithm; and analyzing the results. Specifically, the paper discussed the study area, data and methodology, and image preprocessing using radiometric correction. Image classification and change detection were also discussed. It was concluded that the mine and dump area decreased by 192.5 ha from 2004 to 2008 and was caused by the diminishing reserves in the area and decline in the required production. 5 refs., 2 tabs., 4 figs.

  10. Changes in optical properties, chemistry, and micropore and mesopore characteristics of bituminous coal at the contact with dikes in the Illinois Basin

    Science.gov (United States)

    Mastalerz, Maria; Drobniak, A.; Schimmelmann, A.

    2009-01-01

    Changes in high-volatile bituminous coal (Pennsylvanian) near contacts with two volcanic intrusions in Illinois were investigated with respect to optical properties, coal chemistry, and coal pore structure. Vitrinite reflectance (Ro) increases from 0.62% to 5.03% within a distance of 5.5??m from the larger dike, and from 0.63% to 3.71% within 3.3??m from the small dike. Elemental chemistry of the coal shows distinct reductions in hydrogen and nitrogen content close to the intrusions. No trend was observed for total sulfur content, but decreases in sulfate content towards the dikes indicate thermochemical sulfate reduction (TSR). Contact-metamorphism has a dramatic effect on coal porosity, and microporosity in particular. Around the large dike, the micropore volume, after a slight initial increase, progressively decreases from 0.0417??cm3/g in coal situated 4.7??m from the intrusive contact to 0.0126??cm3/g at the contact. Strongly decreasing mesopore and micropore volumes in the altered zone, together with frequent cleat and fracture filling by calcite, indicate deteriorating conditions for both coalbed gas sorption and gas transmissibility. ?? 2008 Elsevier B.V. All rights reserved.

  11. Automation of technological processes at surface mines in the GDR as one of the main directions of increased coal extraction effectiveness by surface mining

    Energy Technology Data Exchange (ETDEWEB)

    Jona, U.

    1987-12-01

    In the GDR, about 53% of brown coal is mined with the use of overburden conveyor bridges, 27% with the use of belt conveyors, and 20% with the use of rail transport. Compares efficiency and cost per 1 m/sup 3/ of these transport methods. The overburden conveyor bridges, their specifications and microcomputer control are described. Describes utilization of microcomputer techniques, especially the stereochart system of Carl Zeiss Jena, for automated processing of data on surface mine geometry. Other computer applications are also presented, e.g. for surveying, slope stability calculation, and conveyor bridge control. Maintains that application of the KED/KEM microcomputer system for overburden conveyor bridge control increases its effectiveness by 10%, i.e. by 8 million m/sup 3//a.

  12. Effect of burn-off on physical and chemical properties of coal char; Gas ka shinko ni tomonau sekitan char no tokusei henka

    Energy Technology Data Exchange (ETDEWEB)

    Yamada, T.; Tamura, K.; Hashimoto, H.; Funaki, M.; Suzuki, T. [Kitami Institute of Technology, Hokkaido (Japan)

    1996-10-28

    For high-efficiency coal gasification, investigations were given on effect of coal chars with different conversion rates on coal gasification reactivity. In coal gasification, reactivity of char after pyrolysis governs the efficiency. The reference char conversion in CO2 gasification of coal (weight loss) changes linearly in the initial stage of the reaction, but the reactivity declines as the end point is approached. Char surface area is as large as 400 m{sup 2}/g in the initial stage with the conversion at 20%, but it decreases in the final stage. This phenomenon relates closely with changes in pore size and crystalline structure. Change in the Raman value R which shows incompleteness of char graphite structure and amorphous carbon ratio suggests that an active portion with high reactivity is oxidized preferentially, and a portion with low reactivity remains finally. Minerals in coal are known to accelerate the gasification. However, their catalytic effect is related with chemical forms, and complex as they may change into inactive sulfides and silicates under severe reaction conditions. Change in forms of calcium compounds may also be involved in decline of the reactivity in the latter stage. 8 refs., 4 figs.

  13. Using surfaces, ligands, and dimensionality to obtain desired nanostructure properties

    Science.gov (United States)

    Nagpal, Prashant; Singh, Vivek; Ding, Yuchen

    2014-03-01

    Nanostructured materials are intensively investigated to obtain material properties different from their bulk counterparts. It has been demonstrated that nanoscaled semiconductor can have interesting size, shape and morphology dependent optoelectronic properties. But the effect of surfaces, ligands and dimensionality (0D quantum dots to 2D nanosheets) has been largely unexplored. Here, we will show how tuning the surface and dimensionality can affect the electronic states of the semiconductor, and how these states can play an important role in their fundamental photophysical properties or thermal transport. Using the specific case for silicon, we will show how ``new'' surface states in small uniform can lead to light absorption/emission without phonon assistance, while hindering the phonon-drag of charge carriers leading to low Seebeck coefficient for thermoelectric applications. These measurements will shed light on designing appropriate surface, size, and dimensionality for desired applications of nanostructured films.

  14. Oleophobic properties of the step-and-terrace sapphire surface

    Energy Technology Data Exchange (ETDEWEB)

    Muslimov, A. E., E-mail: amuslimov@mail.ru; Butashin, A. V.; Kanevsky, V. M. [Russian Academy of Sciences, Shubnikov Institute of Crystallography, Federal Research Center “Crystallography and Photonics” (Russian Federation)

    2017-03-15

    Sapphire is widely used in production of optical windows for various devices due to its mechanical and optical properties. However, during operation the surface can be affected by fats, oils, and other organic contaminations. Therefore, it is important to improve the oleophobic properties of sapphire windows. In this study, we investigate the interaction of a supersmooth sapphire surface with oleic acid droplets, which imitate human finger printing. It is established that chemical–mechanical polishing with additional annealing in air, which leads to the formation of an atomically smooth sapphire surface, makes it possible to significantly improve the oleophobic properties of the surface. The results are analyzed using the Ventsel–Deryagin homogeneous wetting model.

  15. An overview of underground coal gasification and its applicability for Turkish lignite

    Energy Technology Data Exchange (ETDEWEB)

    Pekpak, E.; Yoncaci, S.; Kilic, M.G. [Middle East Technical Univ., Ankara (Turkey). Dept. of Mining Engineering

    2010-07-01

    Coal is expected to maintain its significance as an energy source for a longer time period than oil and natural gas. Environmental concerns have led to the development of clean coal technologies, such as coal gasification. Coal gasification can be used at either at surface or in underground coal gasification (UCG). UCG has several advantages over surface gasification and conventional mining such as rank low calorific value coals. Coal gasification also has the potential to contribute to the energy supply of a country. Most Turkish coals are lignite and UCG may enable diversification of energy sources of Turkey and may help decrease external dependency on energy. This paper presented a study that matched a UCG technique to the most appropriate (Afsin Elbistan) lignite reserve in Turkey. Two UCG techniques were presented, including the linked vertical well method, and the directional drilling-controlled retractable injection point (CRIP) method. The properties of coal seams and coal properties were also outlined. It was concluded that Cobanbey is the most preferable sector in the Elbistan Lignite Reserve for a pilot study, and that the linked vertical well method could be considered as a candidate method. 17 refs., 6 tabs., 1 fig.

  16. Optimisation of reclamation approaches to land affected by surface coal mining

    Energy Technology Data Exchange (ETDEWEB)

    Kabrna, M.; Hendrychova, M. [Vyzkumny ustav pro hnede uhli a.s. (Czech Republic); Czech Univ. of Life Sciences, Prague (Czech Republic). Faculty of Environmental Science; Salek, M. [Czech Univ. of Life Sciences, Prague (Czech Republic). Faculty of Environmental Science; Rehor, M. [Vyzkumny ustav pro hnede uhli a.s. (Czech Republic)

    2009-07-01

    Since the 1950s, reclamation of land affected by brown coal mining in the Czech Republic has been conducted. Since this time, there has been significant improvement in quality development of reclamation measures. This paper discussed the results of different studies where technically reclaimed sites as well as naturally developed sites were investigated. The paper discussed the methodology of the study as well as results of succession versus reclamation and next preferences. One of the studies that was examined involved four groups of animals that have a close relation to soil and plant vegetation. These included ground beetles, bugs, molluscs, and birds. This study found that the spontaneously developed sites could be characterized by the same or a higher biodiversity than those technically reclaimed. The second study examined bird nest preferences either to domestic or to exotic trees. The results showed that although exotic trees dominate on reclaimed sites, the birds preferred the domestic trees for nesting. It was concluded that the natural succession could play a significant role within reclamation practices, particularly on those sites where higher species diversity is desirable. 10 refs., 2 figs.

  17. Molecular accessibility in solvent swelled coals. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kispert, L.D.

    1994-04-01

    The conversion of coal by an economically feasible catalytic method requires the catalyst to diffuse into the coal sample so that hydrogenation catalysis can occur from within as well as the normal surface catalysis. Thus an estimate of the size, shape, and reactivity, of the pores in the coal before and after the swelling with different solvents is needed so that an optimum sized catalyst will be used. This study characterizes the accessible area found in Argonne Premium Coal Samples (APCS) using a EPR spin probe technique. The properties deduced in this manner correlate well with the findings deduced from SANS, NMR, SEM, SAXS and light scattering measurements. The use of nitroxide spin probes with swelling solvents is a simple way in which to gain an understanding of the pore structure of coals, how it changes in the presence of swelling solvents and the chemistry that occurs at the pore wall. Hydrogen bonding sites occur primarily in low-rank coals and vary in reactive strength as rank is varied. Unswelled coals contain small, spherical pores which disappear when coal is swelled in the presence of polar solvents. Swelling studies of polystyrene-divinyl benzene copolymers implied that coal is polymeric, contains significant quantities of covalent cross-links and the covalent cross-link density increases with rank.

  18. Influence of surface properties on the mechanism of H2S removal by alkaline activated carbons.

    Science.gov (United States)

    Yan, Rong; Chin, Terence; Ng, Yuen Ling; Duan, Huiqi; Liang, David Tee; Tay, Joo Hwa

    2004-01-01

    sulfuric acid as the predominant products. Although both carbons are coal-based and of KOH impregnated type, performances of different carbons differ significantly. A correlation is well established to link the reaction extent with various surface properties. In summary, not only the homogeneous alkali impregnation and physical porosity but also the carbon surface chemistry are significant factors influencing the performances of alkaline activated carbons as H2S adsorbents.

  19. Effect of high-extraction coal mining on surface and ground waters

    International Nuclear Information System (INIS)

    Kendorski, F.S.

    1993-01-01

    Since first quantified around 1979, much new data have become available. In examining the sources of data and the methods and intents of the researchers of over 65 case histories, it became apparent that the strata behaviors were being confused with overlapping vertical extents reported for the fractured zones and aquiclude zones depending on whether the researcher was interested in water intrusion into the mine or in water loss from surface or ground waters. These more recent data, and critical examination of existing data, have led to the realization that the former Aquiclude Zone defined for its ability to prevent or minimize the intrusion of ground or surface waters into mines has another important character in increasing storage of surface and shallow ground waters in response to mining with no permanent loss of waters. This zone is here named the Dilated Zone. Surface and ground waters can drain into this zone, but seldom into the mine, and can eventually be recovered through closing of dilations by mine subsidence progression away from the area, or filling of the additional void space created, or both. A revised model has been developed which accommodates the available data, by modifying the zones as follows: collapse and disaggregation extending 6 to 10 times the mined thickness above the panel; continuous fracturing extending approximately 24 times the mined thickness above the panel, allowing temporary drainage of intersected surface and ground waters; development of a zone of dilated, increased storativity, and leaky strata with little enhanced vertical permeability from 24 to 60 times the mined thickness above the panel above the continuous fracturing zone, and below the constrained or surface effects zones; maintenance of a constrained but leaky zone above the dilated zone and below the surface effects zone; and limited surface fracturing in areas of extension extending up to 50 ft or so beneath the ground surface. 119 ref., 5 figs., 2 tabs

  20. Biotype assessment and evaluation as a method to quantify the external costs related to surface brown coal mining

    International Nuclear Information System (INIS)

    Kabrna, M.; Peleska, O.

    2009-01-01

    Externalities express the uncompensated effects of human individuals on each other and on nature. Externalities include costs and benefits which impact human individuals and environment and are not included in the costs and benefits of their creators and are often defined as the differences between social costs or revenues from economic activity and private costs or revenues. Surface brown coal mining can be characterized by a large range of adverse environmental effects. In order to compensate for the environmental damage caused by mining activities in the Czech Republic, various environmental fees paid by mining companies were introduced to the Czech legislation. The Hessian method of quantifying impacts on the environment is an expert methods that is appropriate for the evaluating environmental damage caused by large-scale impacts on landscape. This paper described the methodology of the Hessian method and its application to a selected opencast mine in north-western Bohemia called the Vrsany-Sverma mine. The paper also discussed current environmental charges in the Czech Republic. It was concluded that the calculated amount of environmental damage caused by surface mining balances the amount of environmental fees currently paid by mining companies. 4 refs., 1 tab.

  1. Nesting success of grassland and savanna birds on reclaimed surface coal mines of the midwestern United States

    Energy Technology Data Exchange (ETDEWEB)

    Galligan, E.W.; DeVault, T.L.; Lima, S.L. [Indiana State University, Terre Haute, IN (United States)

    2006-12-15

    Reclaimed surface coal mines in southwestern Indiana support many grassland and shrub/savanna bird species of conservation concern. We examined the nesting success of birds on these reclaimed mines to assess whether such 'unnatural' places represent productive breeding habitats for such species. We established eight study sites on two large, grassland-dominated mines in southwestern Indiana and classified them into three categories (open grassland, shrub/savanna, and a mixture of grassland and shrub/savanna) based on broad vegetation and landscape characteristics. During the 1999 and 2000 breeding seasons, we found and monitored 911 nests of 31 species. Daily nest survival for the most commonly monitored grassland species ranged from 0.903 (Dickcissel, Spiza americana) to 0.961 (Grasshopper Sparrow, Ammodramus savannarum). Daily survival estimates for the dominant shrub/savanna nesting species ranged from 0.932 (Brown Thrasher, Toxostoma rufum) to 0.982 (Willow Flycatcher, Empidonax traillii). Vegetation and landscape effects on nesting success were minimal, and only Eastern Meadowlarks (Sturnella magna) showed a clear time-of-season effect, with greater nesting success in the first half of the breeding season. Rates of Brown-headed Cowbird (Molothrus ater) parasitism were only 2.1% for grassland species and 12.0% for shrub/savanna species. The nesting success of birds on reclaimed mine sites was comparable to that in other habitats, indicating that reclaimed habitats on surface mines do not necessarily represent reproductive traps for birds.

  2. Effects of coal and wheat husk additives on the physical, thermal and mechanical properties of clay bricks

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, S.; Iqbal, Y.; Muhammad, R.

    2017-07-01

    The use of by-products as additives in brick industry is gaining increased research attention due to their effective role in decreasing the total energy needs of industrial furnaces. In addition, these additives leave pores upon burning, causing a decrease in thermal conductivity and affect the mechanical properties of bricks as well. In the present study, various proportions of coal and wheat husk were used as additives in the initial ingredients of clay bricks. Microstructure, thermal conductivity, coefficient of thermal diffusivity, water absorption, shrinkage, compressive strength and bulk density of fired clay bricks with and without additives were investigated. Clay bricks containing 5–15wt.% additives were found to be within the permissible limits for most of the recommended standard specifications. (Author)

  3. Development, testing, and evaluation of MHD materials and component designs, Volume 3: Electrical properties of coal combustion product

    Science.gov (United States)

    Young, W. E.; Lempert, J.

    1980-11-01

    Laboratory apparatus was assembled to produce a plasma identical in composition and properties to that resulting in an MHD system when coal and air are burned. This was accomplished with a combustion chamber in which benzene, char, sulfur, and seed mixtures were burned with electrically preheated air. The plasma entered a measuring section where temperatures were measured with iridium versus iridium-rhodium thermocouples, with pyrometers, and by means of line reversal. Measurements of electrical conductivity were made with current and voltage probes. Many difficulties were experienced in the operation and calibration of the equipment, however, some readings were obtained in the 19000 C to 20000 C range, averaging 10 to 20 mhos/meter - much higher than predicted theoretically, probably due to electrical leakage. Electrical measurements were made on the Waltz Mill passage during operation. Readings less than 1.0 mhos/meter were obtained which was not unexpected because the plasma temperature approximated 21000 C.

  4. Liquid fuels from Canadian coals

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, G. W.

    1979-06-15

    In Canadian energy planning, the central issue of security of supply must be addressed by developing flexible energy systems that make the best possible use of available resources. For liquid fuel production, oil sands and heavy oil currently appear more attractive than coal or biomass as alternatives to conventional crude oil, but the magnitude of their economic advantage is uncertain. The existence of large resources of oil sands, heavy oils, natural gas and low-sulfur coals in Western Canada creates a unique opportunity for Canadians to optimize the yield from these resources and develop new technology. Many variations on the three basic liquefaction routes - hydroliquefaction, pyrolysis and synthesis - are under investigation around the world, and the technology is advancing rapidly. Each process has merit under certain circumstances. Surface-mineable subbituminous and lignite coals of Alberta and Saskatchewan appear to offer the best combination of favorable properties, deposit size and mining cost, but other deposits in Alberta, Nova Scotia and British Columbia should not be ruled out. The research effort in Canada is small by world standards, but it is unlikely that technology could be imported that is ideally suited to Canadian conditions. Importing technology is undesirable: innovation or process modification to suit Canadian coals and markets is preferred; coprocessing of coal liquids with bitumen or heavy oils would be a uniquely Canadian, exportable technology. The cost of synthetic crude from coal in Canada is uncertain, estimates ranging from $113 to $220/m/sup 3/ ($18 to $35/bbl). Existing economic evaluations vary widely depending on assumptions, and can be misleading. Product quality is an important consideration.

  5. Surface properties of activated carbon treated by cold plasma heating

    Energy Technology Data Exchange (ETDEWEB)

    Norikazu, Kurano [Shigematsu works Co. Ltd., 267 Yashita, Iwatsuki 3390046 (Japan); Yamada, Hiroshi [Shigematsu works Co. Ltd., 267 Yashita, Iwatsuki 3390046 (Japan); Yajima, Tatsuhiko [Faculty of Engineering, Saitama Institute of Technology, 1690 Fusoiji, Okabe 3690293 (Japan); Sugiyama, Kazuo [Faculty of Engineering, Saitama University, 255 Shimo-okubo, Sakura-Ku, Saitama 3388570 (Japan)]. E-mail: sugi@apc.saitama-u.ac.jp

    2007-03-12

    To modify the surface properties of activated carbon powders, we have applied the cold plasma treatment method. The cold plasma was used to be generated in the evacuated reactor vessel by 2.45 GHz microwave irradiation. In this paper, changes of surface properties such as distribution of acidic functional groups and roughness morphology were examined. By the cold plasma treatment, activated carbons with large specific surface area of ca. 2000 m{sup 2}/g or more could be prepared in a minute. The amount of every gaseous organic compound adsorbed on the unit gram of treated activated carbons was more increased that on the unit gram of untreated carbons. Especially, the adsorbed amount of carbon disulfide was remarkably increased even if it was compared by the amount per unit surface area. These results suggest that the surface property of the sample was modified by the plasma treatment. It became apparent by observing SEM photographs that dust and impure particles in macropores of activated carbons were far more reduced by the plasma treatment than by the conventional heating in an electric furnace under vacuum. In addition, a bubble-like surface morphology of the sample was observed by AEM measurement. The amount of acidic functional groups at the surface was determined by using the Boehm's titration method. Consequently, the increase of lactone groups and the decrease of carboxyl groups were also observed.

  6. Modification of Textile Materials' Surface Properties Using Chemical Softener

    Directory of Open Access Journals (Sweden)

    Jurgita KOŽENIAUSKIENĖ

    2011-03-01

    Full Text Available In the present study the effect of technological treatment involving the processes of washing or washing and softening with chemical cationic softener "Surcase" produced in Great Britain on the surface properties of cellulosic textile materials manufactured from cotton, bamboo and viscose spun yarns was investigated. The changes in textile materials surface properties were evaluated using KTU-Griff-Tester device and FEI Quanta 200 FEG scanning electron microscope (SEM. It was observed that the worst hand properties and the higher surface roughness are observed of cotton materials if compared with those of bamboo and viscose materials. Also, it was shown that depending on the material structure the handle parameters of knitted materials are the better than the ones of woven fabrics.http://dx.doi.org/10.5755/j01.ms.17.1.249

  7. Investigation of the surface adsorption and biotribological properties of mucins

    DEFF Research Database (Denmark)

    Madsen, Jan Busk

    to a surface. However, in other instances the inverse properties are desirable. Mucins are found on epithelial surfaces throughout the body and are a key component of the mucus barrier. Here, they facilitate friction reduction, thus lowering the impact of physical abrasions, but they also act as a physical...... charge due to the oligosaccharides being capped by negatively charged species such as sialic acid or sulphate groups. Mucins display phenotypic diversion according to their expression site. This is most pronounced in the oligosaccharide composition of the central domains. The amphiphilic nature of mucins...... and their aqueous lubrication properties have led to them being proposed as possible biocompatible lubricants. In this thesis, we investigate the biotribological properties of two commercially available mucins on the soft, elastomeric and hydrophobic surface of PDMS under different conditions. Due to the presence...

  8. Effective modification of particle surface properties using ultrasonic water mist

    DEFF Research Database (Denmark)

    Genina, Natalja; Räikkönen, Heikki; Heinämäki, Jyrki

    2009-01-01

    The goal of the present study was to design a new technique to modify particle surface properties and, through that, to improve flowability of poorly flowing drug thiamine hydrochloride and pharmaceutical sugar lactose monohydrate of two different grades. The powdered particles were supplied...... properties. It was found that rapid exposition of pharmaceutical materials by water mist resulted in the improvement of powder technical properties. The evident changes in flowability of coarser lactose were obviously due to smoothing of particle surface and decreasing in the level of fines with very slight...... increment in particle size. The changes in thiamine powder flow were mainly due to narrowing in particle size distribution where the tendency for better flow of finer lactose was related to surface and size modifications. The aqueous mist application did not cause any alteration of the crystal structures...

  9. Chemical and mineralogical characterization of highly and less reactive coal from Northern Natal and Venda-Pafuri coalfields in South Africa

    Science.gov (United States)

    Kataka, M. O.; Matiane, A. R.; Odhiambo, B. D. O.

    2018-01-01

    Spontaneous combustion of coal is a major hazard associated with the coal mining industry over centuries. It also a major cause of underground fires in South African collieries and in opencast operations, spoil heaps and stockpiles. Spontaneous combustion incidents are manifested in all major aspects of coal mining namely, underground mining, surface mining, including during sea-borne transportation, storage and waste disposal. Previous studies indicate that there are various factors (both intrinsic and extrinsic) that influence the spontaneous combustion of coals. This paper characterizes highly reactive coal from the Vryheid coalfields and less reactive coal from at Venda-Pafuri coalfield, to identify and delineate some intrinsic coal parameters that are considered to be most critical in terms of heat 'generation' and relationships between the two coals types by tracing their similarities and differences in their spontaneous combustion parameters. Various tests were carried out to characterize these coals in terms of their intrinsic properties, namely: ultimate, proximate, petrographic analysis and Glasser spontaneous tests. The ultimate and proximate analysis showed that spontaneous coal has high contents of carbon, oxygen, and volatile matter as compared to non-spontaneous coal, making it more susceptible to spontaneous combustion. Non-spontaneous coal has higher ash content than the spontaneous coal. Furthermore, the petrographic analysis showed that spontaneous coal has high total reactivity compared to the non-spontaneous coal. Results from Glasser spontaneous test indicate that spontaneous coal absorbs more oxygen than non-spontaneous coal, which explains why spontaneous coal is more susceptible to spontaneous combustion. High reactive coal has low values of critical self-heating temperature (CSHT), indicating that this coal has potential of spontaneous ignition.

  10. Activity of coals of different rank to ozone

    Directory of Open Access Journals (Sweden)

    Vladimir Kaminskii

    2017-12-01

    Full Text Available Coals of different rank were studied in order to characterize their activity to ozone decomposition and changes of their properties at interaction with ozone. Effects of coal rank on their reactivity to ozone were described by means of kinetic modeling. To this end, a model was proposed for evaluation of kinetic parameters describing coals activity to ozone. This model considers a case when coals surface properties change during interaction with ozone (deactivation processes. Two types of active sites (zones at the surface that are able to decompose ozone were introduced in the model differing by their deactivation rates. Activity of sites that are being deactivated at relatively higher rate increases with rank from 2400 1/min for lignite to 4000 1/min for anthracite. Such dependence is related to increase of micropores share in coals structure that grows from lignites to anthracites. Parameter characterizing initial total activity of coals to ozone decomposition also depends on rank by linear trend and vary between 2.40 for lignites up to 4.98 for anthracite. The proposed model could further be used in studies of coals oxidation processes and tendency to destruction under the weathering and oxidation conditions.

  11. Determination of Surface Properties of Liquid Transition Metals

    International Nuclear Information System (INIS)

    Korkmaz, S. D.

    2008-01-01

    Certain surface properties of liquid simple metals are reported. Using the expression derived by Gosh and coworkers we investigated the surface entropy of liquid transition metals namely Fe, Co and Ni. We have also computed surface tensions of the metals concerned. The pair distribution functions are calculated from the solution of Ornstein-Zernike integral equation with Rogers-Young closure using the individual version of the electron-ion potential proposed by Fioalhais and coworkers which was originally developed for solid state. The predicted values of surface tension and surface entropy are in very good agreement with available experimental data. The present study results show that the expression derived by Gosh and coworkers is very useful for the surface entropy by using Fioalhais pseudopotential and Rogers-Young closure

  12. Mechanical properties of coal deformation and its influence on permeability%煤岩变形力学特性及其对渗透性的控制

    Institute of Scientific and Technical Information of China (English)

    孟召平; 王保玉; 谢晓彤; 薛彦东; 杜星原

    2012-01-01

    By the mechanical tests of the coal samples, the physical and mechanical properties of coal and the law of permeability during the complete stress-strain process were studied. It is shown that, compared with the rocks from coal roof and floor, the coal is more prone to plastic deformation with the property of lower mechanical strength, lower elastic modulus and higher Poisson' s ratio. For the coal samples which have obvious strain-softening character during the complete stress-strain process,first,the coal sample volume is compressed and the permeability of coal with stress in- creases slightly or permeability changes little in the micro-cracks closure and elastic deformation stage. After the stress increases higher than the elastic limit, the coal sample gets into the crack propagation stage. The volume strain of coal changs from compression to expansion. The permeability of coal first slowly and then sharply increases with an increas- ing of crack extension. During the strain-softening stage ,the coal permeability achieves the maximum and follows by a sharp decrease. The coal pel~neability after the peak strength is generally greater than that before the peak. For coal samples which have little strain-softening character or strain-hardening during the complete stress-strain process, the maximum permeability is mainly achieved in the plastic deformation stage before the peak. During the strain-hardening stage after the peak strength, the permeability decreases with an increasing of stress. Commonly, the coal permeability after the peak strength is generally less than that before the peak.%通过煤岩力学试验研究了煤岩物理力学性质和煤岩全应力-应变过程中的渗透规律。研究结果表明:煤的力学强度相对煤层顶底板岩石具有低强度、低弹性模量和高泊松比特性,易于产生塑性变形;在全应力-应变过程中具有明显应变软化现象的煤样,在微裂隙闭合和弹性变形阶段,煤岩体积被

  13. The surface properties of biopolymer-coated fruit: A review

    Directory of Open Access Journals (Sweden)

    Diana Cristina Moncayo Martinez

    2013-09-01

    Full Text Available Environmental conservation concerns have led to research and development regarding biodegradable materials from biopolymers, leading to new formulations for edible films and coatings for preserving the quality of fresh fruit and vegetables. Determining fruit skin surface properties for a given coating solution has led to predicting coating efficiency. Wetting was studied by considering spreading, adhesion and cohesion and measuring the contact angle, thus optimising the coating formulation in terms of biopolymer, plasticiser, surfactant, antimicrobial and antioxidant concentration. This work reviews the equations for determining fruit surface properties by using polar and dispersive interaction calculations and by determining the contact angle.

  14. Parametric surface and properties defined on parallelogrammic domain

    OpenAIRE

    Shuqian Fan; Jinsong Zou; Mingquan Shi

    2014-01-01

    Similar to the essential components of many mechanical systems, the geometrical properties of the teeth of spiral bevel gears greatly influence the kinematic and dynamic behaviors of mechanical systems. Logarithmic spiral bevel gears show a unique advantage in transmission due to their constant spiral angle property. However, a mathematical model suitable for accurate digital modeling, differential geometrical characteristics, and related contact analysis methods for tooth surfaces have not b...

  15. Properties of water surface discharge at different pulse repetition rates

    International Nuclear Information System (INIS)

    Ruma,; Yoshihara, K.; Hosseini, S. H. R.; Sakugawa, T.; Akiyama, H.; Akiyama, M.; Lukeš, P.

    2014-01-01

    The properties of water surface discharge plasma for variety of pulse repetition rates are investigated. A magnetic pulse compression (MPC) pulsed power modulator able to deliver pulse repetition rates up to 1000 Hz, with 0.5 J per pulse energy output at 25 kV, was used as the pulsed power source. Positive pulse with a point-to-plane electrode configuration was used for the experiments. The concentration and production yield of hydrogen peroxide (H 2 O 2 ) were quantitatively measured and orange II organic dye was treated, to evaluate the chemical properties of the discharge reactor. Experimental results show that the physical and chemical properties of water surface discharge are not influenced by pulse repetition rate, very different from those observed for under water discharge. The production yield of H 2 O 2 and degradation rate per pulse of the dye did not significantly vary at different pulse repetition rates under a constant discharge mode on water surface. In addition, the solution temperature, pH, and conductivity for both water surface and underwater discharge reactors were measured to compare their plasma properties for different pulse repetition rates. The results confirm that surface discharge can be employed at high pulse repetition rates as a reliable and advantageous method for industrial and environmental decontamination applications.

  16. Numerical modelling of surface subsidence arising from longwall mining of steeply inclined coal seams

    Energy Technology Data Exchange (ETDEWEB)

    Nejad, M.A.; Reddish, D.J. [University of Nottingham, Nottingham (United Kingdom). School of Chemical, Environmental and Mining Engineering

    1998-12-31

    The paper presents results from and the methodology of a numerical modelling investigation into the surface ground movements above longwall mining of inclined and steep seams with varying panel configurations. A modelling approach was developed using a finite difference numercial model Fast Lagrangian Analysis of Continua (FLAC). On the basis of this methodology, representative surface subsidence profiles were simulated and the results of simulations were validated against the UK data using the Subsidence Engineer`s Handbook (SEH) and influence function methods. Furthermore, the proposed methodology was applied to two UK case histories for validation purposes. 15 refs., 7 figs., 3 tabs.

  17. Influence of surface roughness on the friction property of textured surface

    OpenAIRE

    Yuankai Zhou; Hua Zhu; Wenqian Zhang; Xue Zuo; Yan Li; Jianhua Yang

    2015-01-01

    In contrast with dimple textures, surface roughness is a texture at the micro-scale, essentially which will influence the load-bearing capacity of lubricant film. The numerical simulation was carried out to investigate the influence of surface roughness on friction property of textured surface. The lubricant film pressure was obtained using the method of computational fluid dynamics according to geometric model of round dimple, and the renormalization-group k–ε turbulent model was adopted in ...

  18. Characterization of deposits formed on catalyst surfaces during hydrotreatment of coal-derived liquids

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.

    1982-04-01

    Loss of catalyst activity is attributed to the formation of polynuclear aromatic structures on the surface. Heavy species containing N and O heteroatoms were also present in deposits. Phenols, aromatic and heterocyclic compounds are considered to be the precursors for the formation of the deposits. (16 refs.)

  19. Causes of coal degradation at working faces

    Energy Technology Data Exchange (ETDEWEB)

    Sikora, W

    1985-01-01

    Coal comminution by shearer loaders at working faces and factors influencing it are analyzed. Three groups of factors are evaluated: coal mechanical properties, design and specifications of shearer loaders and mining schemes. On the basis of analyses, recommendations for increasing proportion of coarse coal and reducing coal comminution in underground coal mines in Poland are made. Increasing output of coarse coal in coal seams with a high proportion of dull coal is most economic. Increasing power of drive systems for shearer loaders to 500 kW or more decisively influences grain size distribution of coal and increases proportion of coarse coal, especially in seams of dull coal. Gradually increasing cutting depth of a shearer loader negatively influences haulage speed and coarse coal output. Replacing gradual cutting depth increase by attack at the full cutting depth increases proportion of coarse coal. When medium or thick coal seams are mined a coal bench from 0.3 to 0.5 m thick should be left in the roof or between 2 benches cut by 2 cutting drums. The coal bench left in the face disintegrates under the influence of gravity and the proportion of coarse coal increases. Optimizing yield strength of powered supports at a working face is a further method for improving grain size distribution of coal and increasing proportion of coarse coal. 2 references.

  20. Studies of significant properties of filter-type self rescuer for its use in underground coal mine in carbon monoxide exposure

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, A.; Mondal, P.C. [Central Institute of Mining and Fuel Research, Dhanbad (India)

    2007-07-01

    CO is a highly toxic gas; it is the outcome of fire or explosion in underground coal mines. It combines with hemoglobin of coal mine workers and carboxyhemoglobin forms, which reduces the oxygen carrying capacity of blood. A little intake of CO gas, even 0.1% in atmosphere, causes respiratory failure. Filter-type self rescuers (FSR) are a life-saving gas mask breathing apparatus against CO exposure in underground coal mine. The quality of FSR was evaluated in respect of its duration for use, CO conversion by hopcalite, breathing resistance, leak tightness properties, and so on. A scope of improvement is observed in cartridge of self rescuer as well as in the clauses of BIS 9563-1980 in order to increase the duration and improvement in the quality of self rescuers. 12 refs., 2 tabs.

  1. Coal Mine Permit Boundaries

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — ESRI ArcView shapefile depicting New Mexico coal mines permitted under the Surface Mining Control and Reclamation Act of 1977 (SMCRA), by either the NM Mining these...

  2. Long-term effects of surface coal mining on ground-water levels and quality in two small watersheds in eastern Ohio

    International Nuclear Information System (INIS)

    Cunningham, W.L.; Jones, R.L.

    1990-01-01

    Two small eastern Ohio watersheds surface mined for coal and reclaimed were studied during 1986-89. Water level and water quality data were compared with data from investigations conducted during 1976-83 to determine long-term effects of surface mining on the hydrologic system. Before mining, the watersheds were characterized by flatlying sedimentary rocks above clay beds underlying two major coal seams. Two aquifers overlay each under clay. Surface mining removed the upper aquifer, stripped the coal seam, and replaced the spoil, creating a new aquifer with hydraulic and chemical characteristics different from those of the original upper aquifer. Water levels were measured continuously in one well in each aquifer and every 2 months in other wells. Water levels in upper aquifers reached hydraulic equilibrium from 2 to 5 years after mining and, in middle aquifers, water levels increased more than 5 ft during mining; equilibrium occurred almost immediately thereafter. Water samples were collected from three upper aquifer wells, one middle-aquifer well, a seep from the upper aquifer, and the stream in each watershed. Samples were collected in 1986, 1987, 1988, and 1989. In both watersheds, sulfate replaced bicarbonate as the dominant anion in the upper aquifer after mining. In general, significant increases in concentrations of dissolved constituents in groundwater resulted from surface mining. The continued decrease in pH indicates that groundwater had not reached complete geochemical equilibrium in either watershed more than 8 years after mining ended

  3. Reversible Surface Properties of Polybenzoxazine/Silica Nanocomposites Thin Films

    Directory of Open Access Journals (Sweden)

    Wei-Chen Su

    2013-01-01

    Full Text Available We report the reversible surface properties (hydrophilicity, hydrophobicity of a polybenzoxazine (PBZ thin film through simple application of alternating UV illumination and thermal treatment. The fraction of intermolecularly hydrogen bonded O–H⋯O=C units in the PBZ film increased after UV exposure, inducing a hydrophilic surface; the surface recovered its hydrophobicity after heating, due to greater O–H⋯N intramolecular hydrogen bonding. Taking advantage of these phenomena, we prepared a PBZ/silica nanocomposite coating through two simple steps; this material exhibited reversible transitions from superhydrophobicity to superhydrophilicity upon sequential UV irradiation and thermal treatment.

  4. Surface effects on the mechanical properties of nanoporous materials

    International Nuclear Information System (INIS)

    Lu Zixing; Zhang Cungang; Liu Qiang; Yang Zhenyu

    2011-01-01

    In this paper, surface effects on the mechanical behaviour of nanoporous materials are investigated using the theory of surface elasticity and Timoshenko beam theory based on the tetrakaidecahedron (or Kelvin) open-cell foam model. Meanwhile, the influence of surface elasticity and residual surface stress on the mechanical properties of nanoporous materials is discussed. In addition, the results derived from the theory of Euler-Bernoulli beam model are also provided for comparison. Theoretical results show that the effective Young's modulus of the nanoporous materials increases as the diameter of the strut decreases, but in contrast Poisson's ratio and the brittle collapse strength decrease with the diameter of the strut. The contribution of shear deformation to surface effects on elastic properties is more significant, while the surface effects on brittle collapse strength are not sensitive to shear deformation, and it can even be neglected. As the strut size increases, the present results can be reduced to the cases without considering surface effects, which verifies the efficiency of the present model to a certain extent.

  5. Effects on Buildings of Surface Curvature Caused by Underground Coal Mining

    Directory of Open Access Journals (Sweden)

    Haifeng Hu

    2016-08-01

    Full Text Available Ground curvature caused by underground mining is one of the most obvious deformation quantities in buildings. To study the influence of surface curvature on buildings and predict the movement and deformation of buildings caused by ground curvature, a prediction model of the influence function on mining subsidence was used to establish the relationship between surface curvature and wall deformation. The prediction model of wall deformation was then established and the surface curvature was obtained from mining subsidence prediction software. Five prediction lines were set up in the wall from bottom to top and the predicted deformation of each line was used to calculate the crack positions in the wall. Thus, the crack prediction model was obtained. The model was verified by a case study from a coalmine in Shanxi, China. The results show that when the ground curvature is positive, the crack in the wall is shaped like a “V”; when the ground curvature is negative, the crack is shaped like a “∧”. The conclusion provides the basis for a damage evaluation method for buildings in coalmine areas.

  6. Spatial distribution and source identification of heavy metals in surface soils in a typical coal mine city, Lianyuan, China.

    Science.gov (United States)

    Liang, Jie; Feng, Chunting; Zeng, Guangming; Gao, Xiang; Zhong, Minzhou; Li, Xiaodong; Li, Xin; He, Xinyue; Fang, Yilong

    2017-06-01

    In this study, we investigated the pollution degree and spatial distribution of heavy metals and determined their sources in topsoil in a typical coal mine city, Lianyuan, Hunan Province, China. We collected 6078 soil surface samples in different land use types. And the concentrations of Zn, Cd, Cu, Hg, Pb, Sb, As, Mo, V, Mn, Fe and Cr were measured. The average contents of all heavy metals were lower than their corresponding Grade II values of Chinese Soil Quality Standard with the exception of Hg. However, average contents of twelve heavy metals, except for Mn, exceeded their background level in soils in Hunan Province. Based on one-way analysis of variance (ANOVA), the contents of Cu, Zn, Cd, Pb, Hg, Mo and V were related to the anthropogenic source and there were statistically significant differences in their concentrations among different land use patterns. The spatial variation of heavy metal was visualized by GIS. The PMF model was used to ascertain contamination sources of twelve heavy metals and apportion their source contributions in Lianyuan soils. The results showed that the source contributions of the natural source, atmospheric deposition, industrial activities and agricultural activities accounted for 33.6%, 26.05%, 23.44% and 16.91%, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Simulated effects of surface coal mining and agriculture on dissolved solids in the Redwater River, east-central Montana

    Science.gov (United States)

    Ferreira, R.F.; Lambing, J.H.

    1985-01-01

    Dissolved solids concentrations in five reaches of the Redwater River in east-central Montana were simulated to evaluate the effects of surface coal mining and agriculture. A mass-balance model of streamflow and dissolved solids load developed for the Tongue River in southeastern Montana was modified and applied to the Redwater River. Mined acreages, dissolved solids concentrations in mined spoils, and irrigated acreage can be varied in the model to study relative changes in the dissolved solids concentration in consecutive reaches of the river. Because of extreme variability and a limited amount of data, the model was not consecutively validated. Simulated mean and median monthly mean streamflows and consistently larger than those calculated from streamflow records. Simulated mean and median monthly mean dissolved solids loads also are consistently larger than regression-derived values. These discrepancies probably result from extremely variable streamflow, overestimates of streamflow from ungaged tributaries, and weak correlations between streamflow and dissolved solids concentrations. The largest increases in simulated dissolved solids concentrations from mining and agriculture occur from September through January because of smaller streamflows and dissolved solids loads. Different combinations of agriculture and mining under mean flow conditions resulted in cumulative percentage increases of dissolved solids concentrations of less than 5% for mining and less than 2% for agriculture. (USGS)

  8. Coal Reservoir Physical Property Features and CBM Resource Potential in Xingtai Coal-bearing Region%邢台含煤区煤储层物性特征及煤层气资源潜力

    Institute of Scientific and Technical Information of China (English)

    高亮; 上官拴通; 张国斌; 李英英; 闫家栋

    2017-01-01

    degree increasing, and pore diameter inhomogeneously distributed;pore volume and specific surface area of micropores occupied largest proportion. Microfissure density belongs to grade I, part of fissures have filled with vein calcite and granular pyrite. Coal adsorptive capacity is controlled by coal ranks, within a certain pressure range, the capacity increasing along with the pressure increasing, while the adsorptivity deceasing along with the pressure increasing. Coal permeability has large discreteness, belongs to medium to high grade permeability. Estimated potential CBM resources above floor elevation-2000 m have 42.731 billion m3, optimized 6 moderate favorable blocks, among them, the blocks FY, QHY and GZ are preferred for CBM exploration.

  9. Sources of coal-mine drainage and their effects on surface-water chemistry in the Claybank Creek basin and vicinity, north-central Missouri, 1983-84

    Science.gov (United States)

    Blevins, Dale W.

    1989-01-01

    Eighteen sources of drainage related to past coal-mining activity were identified in the Claybank Creek, Missouri, study area, and eight of them were considered large enough to have detectable effects on receiving streams. However, only three sources (two coal-waste sites and one spring draining an underground mine) significantly affected the chemistry of water in receiving streams. Coal wastes in the Claybank Creek basin contributed large quantities of acid drainage to receiving streams during storm runoff. The pH of coal-waste runoff ranged from 2.1 to 2.8. At these small pH values, concentrations of some dissolved metals and dissolved sulfate were a few to several hundred times larger than Federal and State water-quality standards established for these constituents. Effects of acid storm runoff were detected near the mouth of North Fork Claybank Creek where the pH during a small storm was 3.9. Coal wastes in the streambeds and seepage from coal wastes also had significant effects on receiving streams during base flows. The receiving waters had pH values between 2.8 and 3.5, and concentrations of some dissolved metals and dissolved sulfate were a few to several hundred times larger than Federal and State water-quality standards. Most underground mines in the North Fork Claybank Creek basin seem to be hydraulically connected, and about 80 percent of their discharge surfaced at one site. Drainage from the underground mines contributed most of the dissolved constituents in North Fork Claybank Creek during dry weather. Underground-mine water always had a pH near 5.9 and was well-buffered. It had a dissolved-sulfate concentration of about 2,400 milligrams per liter, dissolved-manganese concentrations ranging from 4.0 to 5.3 milligrams per liter, and large concentrations of ferrous iron. Iron was in the ferrous state because of reducing conditions in the mines. When underground-mine drainage reached the ground surface, the ferrous iron was oxidized and precipitated to

  10. Surface properties of CNTs and their interaction with silica.

    Science.gov (United States)

    Sobolkina, Anastasia; Mechtcherine, Viktor; Bellmann, Cornelia; Khavrus, Vyacheslav; Oswald, Steffen; Hampel, Silke; Leonhardt, Albrecht

    2014-01-01

    In order to improve the embedding of carbon nanotubes (CNTs) in cement-based matrices, silica was deposited on the sidewall of CNTs by a sol-gel method. Knowledge of the conditions of CNTs' surfaces is a key issue in understanding the corresponding interaction mechanisms. In this study various types of CNTs synthesized using acetonitrile, cyclohexane, and methane were investigated with regard to their physicochemical surface properties. Significant differences in surface polarity as well as in the wetting properties of the CNTs, depending on the precursors used, were revealed by combining electro-kinetic potential and contact angle measurements. The hydrophobicity of CNTs decreases by utilising the carbon sources in the following order: cyclohexane, methane, and finally acetonitrile. The XPS analysis, applied to estimate the chemical composition at the CNT surface, showed nitrogen atoms incorporated into the tube structure by using acetonitrile as a carbon source. It was found that the simultaneous presence of nitrogen- and/or oxygen-containing sites with different acid-base properties increased the surface polarity of the CNTs, imparting amphoteric characteristics to them and improving their wetting behaviour. Regarding the silica deposition, strong differences in adsorption capacity of the CNTs were observed. The mechanism of silica adsorption through interfacial bond formation was discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Influence of Pyrolysis Temperature and Type of Ligno-Cellulose and Cellulose Biomass on Yield, Specific Surface Area and Mechanical Resistance of Active Coal

    OpenAIRE

    Pohořelý, Michael

    2012-01-01

    In the Czech Republic, there are many contaminated agricultural soils due to anthropogenic activity and geogenic origin. The contaminated biomass of plants grown on the contaminated soils needs to be appropriately disposed of to prevent the re-releace of heavy metals into the environment. One way of processing contaminated biomass is pyrolysis, where the heavy metals are concentrated in biochar (active coal). This can be applied to soil where it improves the physical properties. The aim of ...

  12. Membranes with Surface-Enhanced Antifouling Properties for Water Purification

    Science.gov (United States)

    Shahkaramipour, Nima; Tran, Thien N.; Ramanan, Sankara; Lin, Haiqing

    2017-01-01

    Membrane technology has emerged as an attractive approach for water purification, while mitigation of fouling is key to lower membrane operating costs. This article reviews various materials with antifouling properties that can be coated or grafted onto the membrane surface to improve the antifouling properties of the membranes and thus, retain high water permeance. These materials can be separated into three categories, hydrophilic materials, such as poly(ethylene glycol), polydopamine and zwitterions, hydrophobic materials, such as fluoropolymers, and amphiphilic materials. The states of water in these materials and the mechanisms for the antifouling properties are discussed. The corresponding approaches to coat or graft these materials on the membrane surface are reviewed, and the materials with promising performance are highlighted. PMID:28273869

  13. Improvement of carbon fiber surface properties using electron beam irradiation

    International Nuclear Information System (INIS)

    Pino, E.S.; Machado, L.D.B.; Giovedi, C.

    2007-01-01

    Carbon fiber-reinforced advance composites have been used for structural applications, mainly on account of their mechanical properties. The main factor for a good mechanical performance of carbon fiber-reinforced composite is the interfacial interaction between its components, which are carbon fiber and polymeric matrix. The aim of this study is to improve the surface properties of the carbon fiber using ionizing radiation from an electron beam to obtain better adhesion properties in the resultant composite. EB radiation was applied on the carbon fiber itself before preparing test specimens for the mechanical tests. Experimental results showed that EB irradiation improved the tensile strength of carbon fiber samples. The maximum value in tensile strength was reached using doses of about 250 kGy. After breakage, the morphology aspect of the tensile specimens prepared with irradiated and non-irradiated car- bon fibers were evaluated. SEM micrographs showed modifications on the carbon fiber surface. (authors)

  14. Reflection properties of road surfaces. Contribution to OECD Scientific Expert Group AC4 on Road Surface Characteristics.

    NARCIS (Netherlands)

    Schreuder, D.A.

    1983-01-01

    Photometric characteristics of road surfaces are dealt with. Representation of reflection properties in public lighting; quality criteria of road lighting installations; classification of road surfaces; the relation between reflection characteristics and other properties of road pavements in public

  15. New coal

    Energy Technology Data Exchange (ETDEWEB)

    1979-07-01

    Specially dedicated to coal, this edition comprises a series of articles of general interest dealing with the position of the French coalmining industry (interview with M.P. Gardent), the coal market in France, the work of CERCHAR, etc. New techniques, in-situ gasification of deep coal, gasification of coal by nuclear methods, the conversion of coal into petrol, the Emile Huchet power plant of Houilleres du Bassin de Lorraine, etc., are dealt with.

  16. Coal upgrading

    Energy Technology Data Exchange (ETDEWEB)

    Nunes, S. [IEA Clean Coal Centre, London (United Kingdom)

    2009-10-15

    This report examines current technologies and those likely to be used to produce cleaner coal and coal products, principally for use in power generation and metallurgical applications. Consideration is also given to coal production in the leading coal producing countries, both with developed and developing industries. A range of technologies are considered. These include the coal-based liquid fuel called coal water mixture (CWM) that may compete with diesel, the production of ultra-clean coal (UCC) and coal liquefaction which competes with oil and its products. Technologies for upgrading coal are considered, especially for low rank coals (LRC), since these have the potential to fill the gap generated by the increasing demand for coal that cannot be met by higher quality coals. Potential advantages and downsides of coal upgrading are outlined. Taking into account the environmental benefits of reduced pollution achieved through cleaner coal and reduced transport costs, as well as other positive aspects such as a predictable product leading to better boiler design, the advantages appear to be significant. The drying of low rank coals improves the energy productively released during combustion and may also be used as an adjunct or as part of other coal processing procedures. Coal washing technologies vary in different countries and the implications of this are outlined. Dry separation technologies, such as dry jigging and electrostatic separation, are also described. The demonstration of new technologies is key to their further development and demonstrations of various clean coal technologies are considered. A number of approaches to briquetting and pelletising are available and their use varies from country to country. Finally, developments in upgrading low rank coals are described in the leading coal producing countries. This is an area that is developing rapidly and in which there are significant corporate and state players. 81 refs., 32 figs., 3 tabs.

  17. Underground black-coal mining and its impact on the land surface

    International Nuclear Information System (INIS)

    Pollmann, H.J.; Wilke, F.L.

    1994-01-01

    This book wants to describe the special requirements and consequences resulting from natural conditions at the deposit as well as from decisions and processes of mining operations. On this basis it should be possible to assess the degree to which the impact of mining on defined areas of the land surface can be influenced with reasonable effort. Furthermore, the consequences from conditions governing mining activities for the planning and realization of mining operations and their impact and the granting of permissions and approvals on the part of the mining authorities are discussed. (HS) [de

  18. Mine alarm stations for mine haulage systems in coal surface mines. Stantsiya pozharnoi signalizatsii dlya gorno-transportnogo oborudovaniya ugol'nykh razrezov

    Energy Technology Data Exchange (ETDEWEB)

    Terebilo, N.I.; Bukhanets, B.N.; Rozhkov, V.L.; Martynenko, V.D. (Vsesoyuznyi Nauchno-Issledovatel' skii Institut Gornospasatel' nogo Dela, Donetsk (USSR))

    1988-01-01

    Describes design and operation of the STs fire alarm station developed by the Spetsavtomatika plant in Minsk and successfully tested in the Borodino surface coal mine. The station consists of 14 measuring circuits with the measuring cycle not longer than 4 s. The station detects fires at earthmoving and haulage equipment, cuts off energy supply to fire zones and activates fire extinguishing equipment. The station will be manufactured on a commercial scale. 2 refs.

  19. Mechanical and tribological properties of ion beam-processed surfaces

    International Nuclear Information System (INIS)

    Kodali, P.

    1998-01-01

    The intent of this work was to broaden the applications of well-established surface modification techniques and to elucidate the various wear mechanisms that occur in sliding contact of ion-beam processed surfaces. The investigation included characterization and evaluation of coatings and modified surfaces synthesized by three surface engineering methods; namely, beam-line ion implantation, plasma-source ion implantation, and DC magnetron sputtering. Correlation among measured properties such as surface hardness, fracture toughness, and wear behavior was also examined. This dissertation focused on the following areas of research: (1) investigating the mechanical and tribological properties of mixed implantation of carbon and nitrogen into single crystal silicon by beam-line implantation; (2) characterizing the mechanical and tribological properties of diamond-like carbon (DLC) coatings processed by plasma source ion implantation; and (3) developing and evaluating metastable boron-carbon-nitrogen (BCN) compound coatings for mechanical and tribological properties. The surface hardness of a mixed carbon-nitrogen implant sample improved significantly compared to the unimplanted sample. However, the enhancement in the wear factor of this sample was found to be less significant than carbon-implanted samples. The presence of nitrogen might be responsible for the degraded wear behavior since nitrogen-implantation alone resulted in no improvement in the wear factor. DLC coatings have low friction, low wear factor, and high hardness. The fracture toughness of DLC coatings has been estimated for the first time. The wear mechanism in DLC coatings investigated with a ruby slider under a contact stress of 1 GPa was determined to be plastic deformation. The preliminary data on metastable BCN compound coatings indicated high friction, low wear factor, and high hardness

  20. Physical properties and component contents of brown coal tars obtained in semicoking with a solid heat transfer semicoke

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, V I; Bobrova, A A

    1955-01-01

    Tar obtained in low-temperature carbonization of brown coals with brown-coal semicoke as a heat-transfer medium contains more water and dust, has a lower drop point, and a higher specific gravity, and contains more asphaltene and less paraffin than does tar from the same coal produced in rotating retorts or in shaft kilns. The brown-coal semicoke used as a heat-transfer medium produces partial thermal cracking of the fuel and polymerization of the products of secondary decompositions. The yield of asphaltenes is lowered when the carbonization temperature is raised.

  1. The influence of atomizer internal design and liquid physical properties on effervescent atomizing of coal-water slurry

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Meng; Duan, Yufeng [Southeast Univ., Nanjing (China). Inst. of Thermal Engineering

    2013-07-01

    This study investigated the dependence of effervescent atomizing of coal-water slurry (CWS) on atomizer internal design and fluid properties. Results demonstrate that internal design of atomizer and fluid properties directly affect the two-phase flow pattern inside the atomizer which consequently affects the spray quality. The influence of mixing chamber length on spray quality is not significant at the ALR of 0.15 except for spray 0.75 glycerol/0.248 water/0.002 xanthan mixture. The same trend also found in the effect of angle of aeration holes at ALR of 0.15. Large diameter of the inclined aeration holes shows small SMD for water. The consistency index of fluids has no effect on the spray quality and Sauter Mean Diameter (SMD) increases when polymer additions were added to the glycerin-water mixture. The radial profile of SMD for spray water are almost flat, however, the largest SMD can be obtained at the edge of spray for three other fluids.

  2. Parametric surface and properties defined on parallelogrammic domain

    Directory of Open Access Journals (Sweden)

    Shuqian Fan

    2014-01-01

    Full Text Available Similar to the essential components of many mechanical systems, the geometrical properties of the teeth of spiral bevel gears greatly influence the kinematic and dynamic behaviors of mechanical systems. Logarithmic spiral bevel gears show a unique advantage in transmission due to their constant spiral angle property. However, a mathematical model suitable for accurate digital modeling, differential geometrical characteristics, and related contact analysis methods for tooth surfaces have not been deeply investigated, since such gears are not convenient in traditional cutting manufacturing in the gear industry. Accurate mathematical modeling of the tooth surface geometry for logarithmic spiral bevel gears is developed in this study, based on the basic gearing kinematics and spherical involute geometry along with the tangent planes geometry; actually, the tooth surface is a parametric surface defined on a parallelogrammic domain. Equivalence proof of the tooth surface geometry is then given in order to greatly simplify the mathematical model. As major factors affecting the lubrication, surface fatigue, contact stress, wear, and manufacturability of gear teeth, the differential geometrical characteristics of the tooth surface are summarized using classical fundamental forms. By using the geometrical properties mentioned, manufactura-bility (and its limitation in logarithmic spiral bevel gears is analyzed using precision forging and multi-axis freeform milling, rather than classical cradle-type machine tool based milling or hobbing. Geometry and manufacturability analysis results show that logarithmic spiral gears have many application advantages, but many urgent issues such as contact tooth analysis for precision plastic forming and multi-axis freeform milling also need to be solved in a further study.

  3. [Corrosion resistant properties of different anodized microtopographies on titanium surfaces].

    Science.gov (United States)

    Fangjun, Huo; Li, Xie; Xingye, Tong; Yueting, Wang; Weihua, Guo; Weidong, Tian

    2015-12-01

    To investigate the corrosion resistant properties of titanium samples prepared by anodic oxidation with different surface morphologies. Pure titanium substrates were treated by anodic oxidation to obtain porous titanium films in micron, submicron, and micron-submicron scales. The surface morphologies, coating cross-sectional morphologies, crystalline structures, and surface roughness of these samples were characterized. Electrochemical technique was used to measure the corrosion potential (Ecorr), current density of corrosion (Icorr), and polarization resistance (Rp) of these samples in a simulated body fluid. Pure titanium could be modified to exhibit different surface morphologies by the anodic oxidation technique. The Tafel curve results showed that the technique can improve the corrosion resistance of pure titanium. Furthermore, the corrosion resistance varied with different surface morphologies. The submicron porous surface sample demonstrated the best corrosion resistance, with maximal Ecorr and Rp and minimal Icorr. Anodic oxidation technology can improve the corrosion resistance of pure titanium in a simulated body fluid. The submicron porous surface sample exhibited the best corrosion resistance because of its small surface area and thick barrier layer.

  4. Directional radiative properties of anisotropic rough silicon and gold surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Lee, H.J.; Chen, Y.B.; Zhang, Z.M. [George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

    2006-11-15

    Recent studies have shown that the topography of some chemically etched microrough silicon surfaces is non-Gaussian and may be strongly anisotropic. However, the bidirectional reflectance distribution function (BRDF) of anisotropic surfaces has not been fully understood. The present study uses the Monte Carlo method to investigate the out-of-plane BRDF, multiple scattering, and the change of the polarization state upon reflection. Two ray-tracing algorithms are developed that incorporate the surface topography or slope distribution of the samples obtained by the use of an atomic force microscope. The predicted BRDFs for silicon surfaces with or without a gold coating are in reasonable agreement with the results measured using a laser scatterometer at a wavelength of 635nm. The employment of surface topographic data is indispensable to the BRDF modeling of anisotropic surfaces. While first-order scattering makes the dominant contribution to reflections from the studied surfaces, it is critical to consider the polarization state change in order to correctly predict the out-of-plane BRDF. The versatile Monte Carlo modeling tools developed through the present study help gain a better understanding of the directional radiative properties of microrough surfaces and, furthermore, will have an impact on thermal metrology in the semiconductor industry. (author)

  5. Features of development process displacement of earth’s surface when dredging coal in Eastern Donbas

    Science.gov (United States)

    Posylniy, Yu V.; Versilov, S. O.; Shurygin, D. N.; Kalinchenko, V. M.

    2017-10-01

    The results of studies of the process of the earth’s surface displacement due to the influence of the adjacent longwalls are presented. It is established that the actual distributions of soil subsidence in the fall and revolt of the reservoir with the same boundary settlement processes differ both from each other and by the distribution of subsidence, recommended by the rules of structures protection. The application of the new boundary criteria - the relative subsidence of 0.03 - allows one to go from two distributions to one distribution, which is also different from the sedimentation distribution of protection rules. The use of a new geometrical element - a virtual point of the mould - allows one to transform the actual distribution of subsidence in the model distribution of rules of constructions protection. When transforming the curves of subsidence, the boundary points vary and, consequently, the boundary corners do.

  6. p-Chlorophenol adsorption on activated carbons with basic surface properties

    Science.gov (United States)

    Lorenc-Grabowska, Ewa; Gryglewicz, Grażyna; Machnikowski, Jacek

    2010-05-01

    The adsorption of p-chlorophenol (PCP) from aqueous solution on activated carbons (ACs) with basic surface properties has been studied. The ACs were prepared by two methods. The first method was based on the modification of a commercial CWZ AC by high temperature treatment in an atmosphere of ammonia, nitrogen and hydrogen. The second approach comprised the carbonization followed by activation of N-enriched polymers and coal tar pitch using CO 2 and steam as activation agent. The resultant ACs were characterized in terms of porous structure, elemental composition and surface chemistry (pH PZC, acid/base titration, XPS). The adsorption of PCP was carried out from an aqueous solution in static conditions. Equilibrium adsorption isotherm was of L2 type for polymer-based ACs, whereas L3-type isotherm was observed for CWZ ACs series. The Langmuir monolayer adsorption capacity was related to the porous structure and the amount of basic sites. A good correlation was found between the adsorption capacity and the volume of micropores with a width water molecule adsorption on the PCP uptake is discussed.

  7. Methane of the coal

    International Nuclear Information System (INIS)

    Vasquez, H.

    1997-01-01

    In the transformation process of the vegetable material to the coal (Carbonization), the products that are generated include CH 4, CO2, N2 and H2. The methane is generated by two mechanisms: below 50 centigrade degree, as product of microbial decomposition, the methanogenic is generated; and above 50 centigrade degree, due to the effects of the buried and increase of the range of the coal, the thermogenic methane is detachment, as a result of the catagenic. The generated methane is stored in the internal surfaces of the coal, macro and micro pores and in the natural fractures. The presence of accumulations of gas of the coal has been known in the entire world by many years, but only as something undesirable for its danger in the mining exploitation of the coal

  8. Coal-92

    International Nuclear Information System (INIS)

    Hillring, B.; Sparre, C.

    1992-11-01

    Swedish consumption of coal and coke during 1991 and trends in technology, environment and market aspects of coal use are reported. Steam coal use in the heating sector was unchanged from 1991, 1.2 Mtons. Reduced consumption in smaller district heating units (due to conversion to biofuels and gas) was compensated by increased use for power generation in cogeneration plants. Coal consumption in industry fell 0.10 Mton to 0.84 Mton due to lower production in one industry branch. Import of steam coal was 1.1 Mton (down 0.5 Mton from 1990) since new rules for strategic reserves allowed a reduction of stocks. During the last five years stocks have been reduced by 2 Mtons. Import of metallurgical coal was 1.6 Mton, unchanged from 1990. The report also gives statistics for the coal using plants in Sweden, on coal R and D, and on emission laws for coal firing. (9 tabs., 2 figs.)

  9. The Indonesian coal industry

    International Nuclear Information System (INIS)

    Cook, A.; Daulay, B.

    2000-01-01

    In this comprehensive article the authors describe the origins and progress of the Indonesian coal industry and the role it plays, and will play, in the domestic energy scene and world coal trade. In the '80s, the Indonesian coal industry laid the basis for major expansion such that coal production rose from under a million tonnes in 1983 to 10.6 million tonnes in 1990, 50.9 million tonnes by 1996 and 61.2 million tonnes in 1992. At the same time, exports have increased from 0.4 million tonnes to 44.8 million tonnes. Current export levels are higher than originally expected, due in part to a slow down in the construction of electric power stations and a partial switch to natural gas. This has slowed the rate at which domestic coal demand has built up. The majority of coals currently exported are low rank steam coals, but some of the higher rank and very low ash coals are used for blast furnace injection, and a very small proportion may even be used within coking blends, even though they have poor coking properties. The Indonesian coal industry has developed very rapidly over the last six years to become a significant exporter, especially within the ASEAN context. The resources base appears to be large enough to support further increases in production above those already planned. It is probable that resources and reserves can be increased above the current levels. It is likely that some reserves of high value coals can be found, but it is also probable that the majority of additions to reserves will be lower in rank (and therefore quality) compared with the average of coals currently being mined. Reserves of qualities suitable for export will support that industry for a considerable period of time. However, in the longer term, the emphasis of production will increasingly swing to the domestic market

  10. Microphase separated structure and surface properties of fluorinated polyurethane resin

    International Nuclear Information System (INIS)

    Sudaryanto; Nishino, T.; Hori, Y.; Nakamae, K.

    2000-01-01

    The effect of fluorination on microphase separation and surface properties of segmented polyurethane (PU) resin were investigated. A series of fluorinated polyurethane resin (FPU) was synthesized by reacting a fluorinated diol with aromatic diisocyanate. The microphase separated structure of FPU was studied by thermal analysis, and small angle X-ray scattering (SAXS) as well as wide angle X-ray diffraction (WAXD). The surface structure and properties were characterized by X-ray photoelectron spectroscopy (XPS) and dynamic contact angle measurement. The incorporation of fluorine into hard segment brings the FPU to have a higher hard domain cohesion and increase the phase separation, however localization of fluorine on the surface could not be observed. On the other hands, localization of fluorine on the surface could be achieved for soft segment fluorinated PU without any significant change in microphase separated structure. The result from this study give an important basic information for designing PU coating material with a low surface energy and strong adhesion as well as for development of release film on pressure sensitive adhesive tape. (author)

  11. Oxidative nanopatterning of titanium generates mesoporous surfaces with antimicrobial properties

    Directory of Open Access Journals (Sweden)

    Variola F

    2014-05-01

    Full Text Available Fabio Variola,1,2 Sylvia Francis Zalzal,3 Annie Leduc,3 Jean Barbeau,3 Antonio Nanci31Faculty of Engineering, Department of Mechanical Engineering, 2Faculty of Science, Department of Physics, University of Ottawa, Ottawa, ON, 3Faculty of Dental Medicine, Université de Montréal, Montreal, QC, CanadaAbstract: Mesoporous surfaces generated by oxidative nanopatterning have the capacity to selectively regulate cell behavior, but their impact on microorganisms has not yet been explored. The main objective of this study was to test the effects of such surfaces on the adherence of two common bacteria and one yeast strain that are responsible for nosocomial infections in clinical settings and biomedical applications. In addition, because surface characteristics are known to affect bacterial adhesion, we further characterized the physicochemical properties of the mesoporous surfaces. Focused ion beam (FIB was used to generate ultrathin sections for elemental analysis by energy-dispersive X-ray spectroscopy (EDS, nanobeam electron diffraction (NBED, and high-angle annular dark field (HAADF scanning transmission electron microscopy (STEM imaging. The adherence of Staphylococcus aureus, Escherichia coli and Candida albicans onto titanium disks with mesoporous and polished surfaces was compared. Disks with the two surfaces side-by-side were also used for direct visual comparison. Qualitative and quantitative results from this study indicate that bacterial adhesion is significantly hindered by the mesoporous surface. In addition, we provide evidence that it alters structural parameters of C. albicans that determine its invasiveness potential, suggesting that microorganisms can sense and respond to the mesoporous surface. Our findings demonstrate the efficiency of a simple chemical oxidative treatment in generating nanotextured surfaces with antimicrobial capacity with potential applications in the implant manufacturing industry and hospital setting

  12. Microstructure and properties of cast iron after laser surface hardening

    Directory of Open Access Journals (Sweden)

    Stanislav

    2013-12-01

    Full Text Available Laser surface hardening of cast iron is not trivial due to the material’s heterogeneity and coarse-grained microstructure, particularly in massive castings. Despite that, hardening of heavy moulds for automotive industry is in high demand. The present paper summarises the findings collected over several years of study of materials structure and surface properties. Phase transformations in the vicinity of graphite are described using examples from production of body parts in automotive industry. The description relates to formation of martensite and carbide-based phases, which leads to hardness values above 65 HRC and to excellent abrasion resistance.

  13. Effects of the addition of oil shale ash and coal ash on physic-chemical properties of CPJ45 cement

    Directory of Open Access Journals (Sweden)

    Nabih K.

    2014-04-01

    Full Text Available We focused our research on recycling industrial wastes, fly ash (F.A, bottom ash (B.A and oil shale ash (S.A in cement production. The study concerns physico-chemical characterization of these products and the influence of their addition on the mechanical proprieties of the CPJ45 cement. XRF allowed us to rank the three additives used according to their contents on major oxides. Coal ashes belong to the class F, and thus possess poozzolanic properties and oil shale ash belongs to the class C and possesses hydraulic and poozolanic properties. The crystalline phases constituting each ash were analysed by XRD. We observe in bottom ash the presence of quartz and mullite. The same crystals are found in fly ash with hematite and magnetite. Oil shale ash is composed of quartz, anhydrite, gehlenite, wollastonite and periclase. The microstructures of fly ash and bottom ash were studied using SEM. The bottom ash was composed respectively of fine particles that are generally irregularly shaped, their dimensions are between 5 and 28μm and of big particles(300 μm. The EDX analysis coupled with an electronic microscope provided some information about the major elements that constitute our samples. The dehydrations of anhydrous and three days hydrated cement were examined by DSC. For hydrated cements we noticed endothermic peaks related to the dehydration of CSH, CH and decomposition of carbonates. The study of the mechanical properties of CPJ45 cement by adding different proportions of fly ash, bottom ash and oil shale ash helped clarifying the percentage of ash that leaded to improve the 28 days mechanical strength. The results show that the cements studied have their maximum mechanical resistance with the addition at 7% of fly ash or 10% of oil shale ash.

  14. Preparation and evaluation of coal-derived activated carbons for removal of mercury vapor from simulated coal combustion flue fases

    Science.gov (United States)

    Hsi, H.-C.; Chen, S.; Rostam-Abadi, M.; Rood, M.J.; Richardson, C.F.; Carey, T.R.; Chang, R.

    1998-01-01

    Coal-derived activated carbons (CDACs) were tested for their suitability in removing trace amounts of vapor-phase mercury from simulated flue gases generated by coal combustion. CDACs were prepared in bench-scale and pilot-scale fluidized-bed reactors with a three-step process, including coal preoxidation, carbonization, and then steam activation. CDACs from high-organicsulfur Illinois coals had a greater equilibrium Hg0 adsorption capacity than activated carbons prepared from a low-organic-sulfur Illinois coal. When a low-organic-sulfur CDAC was impregnated with elemental sulfur at 600 ??C, its equilibrium Hg0 adsorption capacity was comparable to the adsorption capacity of the activated carbon prepared from the high-organicsulfur coal. X-ray diffraction and sulfur K-edge X-ray absorption near-edge structure examinations showed that the sulfur in the CDACs was mainly in organic forms. These results suggested that a portion of the inherent organic sulfur in the starting coal, which remained in the CDACs, played an important role in adsorption of Hg0. Besides organic sulfur, the BET surface area and micropore area of the CDACs also influenced Hg0 adsorption capacity. The HgCl2 adsorption capacity was not as dependent on the surface area and concentration of sulfur in the CDACs as was adsorption of Hg0. The properties and mercury adsorption capacities of the CDACs were compared with those obtained for commercial Darco FGD carbon.

  15. Trace element geochemistry and surface water chemistry of the Bon Air coal, Franklin County, Cumberland Plateau, southeast Tennessee

    Science.gov (United States)

    Shaver, S.A.; Hower, J.C.; Eble, C.F.; McLamb, E.D.; Kuers, K.

    2006-01-01

    Mean contents of trace elements and ash in channel, bench-column, and dump samples of the abandoned Bon Air coal (Lower Pennsylvanian) in Franklin County, Tennessee are similar to Appalachian COALQUAL mean values, but are slightly lower for As, Fe, Hg, Mn, Na, Th, and U, and slightly higher for ash, Be, Cd, Co, Cr, REEs, Sr, and V, at the 95% confidence level. Compared to channel samples, dump sample means are slightly lower in chalcophile elements (As, Cu, Fe, Ni, Pb, S, Sb, and V) and slightly higher in clay or heavy-mineral elements (Al, K, Mn, REEs, Th, Ti, U, and Y), but at the 95% confidence level, only As and Fe are different. Consistent abundances of clay or heavy-mineral elements in low-Br, high-S, high-ash benches that are relatively enriched in quartz and mire-to-levee species like Paralycopodites suggest trace elements are largely fluvial in origin. Factor analysis loadings and correlation coefficients between elements suggest that clays host most Al, Cr, K, Ti, and Th, significant Mn and V, and some Sc, U, Ba, and Ni. Heavy accessory minerals likely house most REEs and Y, lesser Sc, U, and Th, and minor Cr, Ni, and Ti. Pyrite appears to host As, some V and Ni, and perhaps some Cu, but Cu probably exists largely as chalcopyrite. Data suggest that organic debris houses most Be and some Ni and U, and that Pb and Sb occur as Pb-Sb sulfosalt(s) within organic matrix. Most Hg, and some Mn and Y, appear to be hosted by calcite, suggesting potential Hg remobilization from original pyrite, and Hg sorption by calcite, which may be important processes in abandoned coals. Most Co, Zn, Mo, and Cd, significant V and Ni, and some Mn probably occur in non-pyritic sulfides; Ba, Sr, and P are largely in crandallite-group phosphates. Selenium does not show organic or "clausthalite" affinities, but Se occurrence is otherwise unclear. Barium, Mn, Ni, Sc, U, and V, with strongly divided statistical affinities, likely occur subequally in multiple modes. For study area

  16. Development of coal resources

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    It is an important issue to expand stable coal supply areas for Japan, especially to assure stable supply of overseas coals. The investigations on geological structures in foreign countries perform surveys on geological structures in overseas coal producing countries and basic feasibility studies. The investigations select areas with greater business risks in coal producing countries and among private business entities. The geological structure investigations were carried out on China, Indonesia and Malaysia and the basic feasibility studies on Indonesia during fiscal 1994. The basic coal resource development investigations refer to the results of previous physical explorations and drilling tests to develop practical exploration technologies for coal resources in foreign countries. The development feasibility studies on overseas coals conduct technological consultation, surface surveys, physical explorations, and trial drilling operations, and provide fund assistance to activities related thereto. Fiscal 1994 has provided fund assistance to two projects in Indonesia and America. Fund loans are provided on investigations for development and import of overseas coals and other related activities. Liability guarantee for development fund is also described.

  17. Surface properties of Ti-6Al-4V alloy part I: Surface roughness and apparent surface free energy.

    Science.gov (United States)

    Yan, Yingdi; Chibowski, Emil; Szcześ, Aleksandra

    2017-01-01

    Titanium (Ti) and its alloys are the most often used implants material in dental treatment and orthopedics. Topography and wettability of its surface play important role in film formation, protein adhesion, following osseointegration and even duration of inserted implant. In this paper, we prepared Ti-6Al-4V alloy samples using different smoothing and polishing materials as well the air plasma treatment, on which contact angles of water, formamide and diiodomethane were measured. Then the apparent surface free energy was calculated using four different approaches (CAH, LWAB, O-W and Neumann's Equation of State). From LWAB approach the components of surface free energy were obtained, which shed more light on the wetting properties of samples surface. The surface roughness of the prepared samples was investigated with the help of optical profilometer and AFM. It was interesting whether the surface roughness affects the apparent surface free energy. It was found that both polar interactions the electron donor parameter of the energy and the work of water adhesion increased with decreasing roughness of the surfaces. Moreover, short time plasma treatment (1min) caused decrease in the surface hydrophilic character, while longer time (10min) treatment caused significant increase in the polar interactions and the work of water adhesion. Although Ti-6Al-4V alloy has been investigated many times, to our knowledge, so far no paper has been published in which surface roughness and changes in the surface free energy of the alloy were compared in the quantitative way in such large extent. This novel approach deliver better knowledge about the surface properties of differently smoothed and polished samples which may be helpful to facilitate cell adhesion, proliferation and mineralization. Therefore the results obtained present also potentially practical meaning. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Influence of thermoplastic properties on coking pressure generation: Part 1 - A study of single coals of various rank

    Energy Technology Data Exchange (ETDEWEB)

    John J. Duffy; Merrick R. Mahoney; Karen M. Steel [University of Nottingham, Nottingham (United Kingdom). Nottingham Fuel and Energy Centre

    2010-07-15

    In this study a number of high coking pressure coals with different fluidities were evaluated alongside a number of low pressure coals also with differing fluidities. This was to establish rheological parameters within which a coal may be considered potentially dangerous with regards to coking pressure. The results have confirmed and elaborated on previous findings which show that parallel plate displacement ({Delta}L) and axial force profiles can be used to distinguish between high and low pressure coals, with peak values indicating cell rupture and subsequent pore network formation. This is thought to correspond with plastic layer compaction in the coke oven. For low pressure coals pore coalescence occurs quite early in the softening process when viscosity/elasticity are decreasing and consequently a large degree of contraction/collapse is observed. For higher pressure coals the process is delayed since pore development and consequently wall thinning progress at a slower rate. If or when a pore network is established, a lower degree of contraction/collapse is observed because the event occurs closer to resolidification, where viscosity and elasticity are increasing. For the higher fluidity, high coking pressure coals, a greater degree of swelling is observed prior to cell rupture, and this is considered to be the primary reason for the high coking pressure observed with these coals. An additional consequence of these events is that high pressure coals are likely to contain a higher proportion of closed cells both at and during resolidification, reducing permeability in both the semi-coke and high temperature plastic layers, respectively. Using a rheological mapping approach to follow viscoelastic changes during carbonisation it has been possible to identify specific regions associated with dangerous coals. 76 refs., 11 figs., 3 tabs.

  19. Friction Properties of Surface-Fluorinated Carbon Nanotubes

    Science.gov (United States)

    Wal, R. L. Vander; Miyoshi, K.; Street, K. W.; Tomasek, A. J.; Peng, H.; Liu, Y.; Margrave, J. L.; Khabashesku, V. N.

    2005-01-01

    Surface modification of the tubular or sphere-shaped carbon nanoparticles through chemical treatment, e.g., fluorination, is expected to significantly affect their friction properties. In this study, a direct fluorination of the graphene-built tubular (single-walled carbon nanotubes) structures has been carried out to obtain a series of fluorinated nanotubes (fluoronanotubes) with variable C(n)F (n =2-20) stoichiometries. The friction coefficients for fluoronanotubes, as well as pristine and chemically cut nanotubes, were found to reach values as low as 0.002-0.07, according to evaluation tests run in contact with sapphire in air of about 40% relative humidity on a ball-on-disk tribometer which provided an unidirectional sliding friction motion. These preliminary results demonstrate ultra-low friction properties and show a promise in applications of surface modified nanocarbons as a solid lubricant.

  20. Surface properties of hydrogenated nanodiamonds: a chemical investigation.

    Science.gov (United States)

    Girard, H A; Petit, T; Perruchas, S; Gacoin, T; Gesset, C; Arnault, J C; Bergonzo, P

    2011-06-28

    Hydrogen terminations (C-H) confer to diamond layers specific surface properties such as a negative electron affinity and a superficial conductive layer, opening the way to specific functionalization routes. For example, efficient covalent bonding of diazonium salts or of alkene moieties can be performed on hydrogenated diamond thin films, owing to electronic exchanges at the interface. Here, we report on the chemical reactivity of fully hydrogenated High Pressure High Temperature (HPHT) nanodiamonds (H-NDs) towards such grafting, with respect to the reactivity of as-received NDs. Chemical characterizations such as FTIR, XPS analysis and Zeta potential measurements reveal a clear selectivity of such couplings on H-NDs, suggesting that C-H related surface properties remain dominant even on particles at the nanoscale. These results on hydrogenated NDs open up the route to a broad range of new functionalizations for innovative NDs applications development. This journal is © the Owner Societies 2011

  1. Correlation between surface microstructure and optical properties of porous silicon

    Directory of Open Access Journals (Sweden)

    Saeideh Rhramezani Sani

    2007-12-01

    Full Text Available   We have studied the effect of increasing porosity and its microstructure surface variation on the optical and dielectric properties of porous silicon. It seems that porosity, as the surface roughness within the range of a few microns, shows quantum effect in the absorption and reflection process of porous silicon. Optical constants of porous silicon at normal incidence of light with wavelength in the range of 250-3000 nm have been calculated by Kramers-Kroning method. Our experimental analysis shows that electronic structure and dielectric properties of porous silicon are totally different from silicon. Also, it shows that porous silicon has optical response in the visible region. This difference was also verified by effective media approximation (EMA.

  2. Soil formation and soil biological properties post mining sites after coal mining in central Europe

    Czech Academy of Sciences Publication Activity Database

    Kaneda, Satoshi; Frouz, Jan; Krištůfek, Václav; Elhottová, Dana; Pižl, Václav; Starý, Josef; Háněl, Ladislav; Tajovský, Karel; Chroňáková, Alica

    2007-01-01

    Roč. 53, - (2007), s. 13 ISSN 0288-5840. [Annual Meeting Japanese Society of Soil Science and Plant Nutrition . 22.08.2007, Setagaya city] Institutional research plan: CEZ:AV0Z60660521 Keywords : soil formation * soil biological properties * post mining sites Subject RIV: EH - Ecology, Behaviour

  3. Magnetic Nanoparticles: Surface Effects and Properties Related to Biomedicine Applications

    OpenAIRE

    Issa, Bashar; Obaidat, Ihab M.; Albiss, Borhan A.; Haik, Yousef

    2013-01-01

    Due to finite size effects, such as the high surface-to-volume ratio and different crystal structures, magnetic nanoparticles are found to exhibit interesting and considerably different magnetic properties than those found in their corresponding bulk materials. These nanoparticles can be synthesized in several ways (e.g., chemical and physical) with controllable sizes enabling their comparison to biological organisms from cells (10–100 μm), viruses, genes, down to proteins (3–50 nm). The opti...

  4. Correlation properties of surface and percolation transfer of electrons

    International Nuclear Information System (INIS)

    Bakunin, O.G.

    2002-01-01

    In this work was received equation, connecting correlatively properties of surface with electrons distribution function. Usually for equilibrium is necessary a large number of collisions. Collisions are 'destroying' correlations. In case rare collisions large importance have correlations and 'memory' effects. Non-Markov's character of emitting particles by surface lead to strongly nonequilibrium condition of 'gas'. Here kinetic equation of diffusive form does not apply. Classical kinetic equation are described only conditions near to equilibrium. This work offers to use ideas anomal diffusion in phase-space. The correlation properties of surface describe by correlations of velocities of emitting electrons: B(t). We offer to use functional equation for probability collision instead of kinetic equation: ∫ 0 ν 0 W noncoll F(ν) dv = 1 - B(t). This functional allow to consider 'memory' effects. It is important for consideration of electrons and clusters near surfaces. Distribution function become direct connected with correlations. In classical Kubo-Mory theory of transfer is necessary to get nondivergences integral: D ∝ ∫ 0 ∞ B(t). In considering case we can use even 'power function'. It was used 'slow' correlation function as Kohlraush in calculations. The information about kinetics and correlations properties are containing in one functional equation. It was received solution of this equation in form Levy function: F(ν) ∝ 1/ν α exp(-1/ν). The solution of this form can not be get with help asymptotic methods of kinetic theory. Asymptotics of solution have scale-invariant character F(V) ∝ 1/V α . This indicate on fractal properties phase-space. (author)

  5. 30 CFR 772.13 - Coal exploration compliance duties.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Coal exploration compliance duties. 772.13... INTERIOR SURFACE COAL MINING AND RECLAMATION OPERATIONS PERMITS AND COAL EXPLORATION SYSTEMS UNDER REGULATORY PROGRAMS REQUIREMENTS FOR COAL EXPLORATION § 772.13 Coal exploration compliance duties. (a) All...

  6. Coal 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    ACR's Coal 1992, the successor to the ACR Coal Marketing Manual, contains a comprehensive set of data on many aspects of the Australian coal industry for several years leading up to 1992. Tables and text give details of coal production and consumption in New South Wales, Queensland and other states. Statistics of the Australian export industry are complemented by those of South Africa, USA, New Zealand, Canada, Indonesia, China, Colombia, Poland and ex-USSR. Also listed are prices of Australian coking and non-coking coal, Australian coal stocks (and those of other major countries), loading port capacities, freight rates and coal quality requirements (analysis of coals by brand and supplier). A listing of Australian coal exporting companies is provided. A description of the spot Coal Screen Dealing System is given. World hard coal imports are listed by country and coal imports by major Asian countries tabulated. A forecast of demand by coal type and country up to the year 2000 is included.

  7. Surface, structural and tensile properties of proton beam irradiated zirconium

    Energy Technology Data Exchange (ETDEWEB)

    Rafique, Mohsin; Chae, San; Kim, Yong-Soo, E-mail: yongskim@hanyang.ac.kr

    2016-02-01

    This paper reports the surface, structural and tensile properties of proton beam irradiated pure zirconium (99.8%). The Zr samples were irradiated by 3.5 MeV protons using MC-50 cyclotron accelerator at different doses ranging from 1 × 10{sup 13} to 1 × 10{sup 16} protons/cm{sup 2}. Both un-irradiated and irradiated samples were characterized using Field Emission Scanning Electron Microscope (FESEM), X-ray Diffraction (XRD) and Universal Testing Machine (UTM). The average surface roughness of the specimens was determined by using Nanotech WSxM 5.0 develop 7.0 software. The FESEM results revealed the formation of bubbles, cracks and black spots on the samples’ surface at different doses whereas the XRD results indicated the presence of residual stresses in the irradiated specimens. Williamson–Hall analysis of the diffraction peaks was carried out to investigate changes in crystallite size and lattice strain in the irradiated specimens. The tensile properties such as the yield stress, ultimate tensile stress and percentage elongation exhibited a decreasing trend after irradiation in general, however, an inconsistent behavior was observed in their dependence on proton dose. The changes in tensile properties of Zr were associated with the production of radiation-induced defects including bubbles, cracks, precipitates and simultaneous recovery by the thermal energy generated with the increase of irradiation dose.

  8. Surface, structural and tensile properties of proton beam irradiated zirconium

    Science.gov (United States)

    Rafique, Mohsin; Chae, San; Kim, Yong-Soo

    2016-02-01

    This paper reports the surface, structural and tensile properties of proton beam irradiated pure zirconium (99.8%). The Zr samples were irradiated by 3.5 MeV protons using MC-50 cyclotron accelerator at different doses ranging from 1 × 1013 to 1 × 1016 protons/cm2. Both un-irradiated and irradiated samples were characterized using Field Emission Scanning Electron Microscope (FESEM), X-ray Diffraction (XRD) and Universal Testing Machine (UTM). The average surface roughness of the specimens was determined by using Nanotech WSxM 5.0 develop 7.0 software. The FESEM results revealed the formation of bubbles, cracks and black spots on the samples' surface at different doses whereas the XRD results indicated the presence of residual stresses in the irradiated specimens. Williamson-Hall analysis of the diffraction peaks was carried out to investigate changes in crystallite size and lattice strain in the irradiated specimens. The tensile properties such as the yield stress, ultimate tensile stress and percentage elongation exhibited a decreasing trend after irradiation in general, however, an inconsistent behavior was observed in their dependence on proton dose. The changes in tensile properties of Zr were associated with the production of radiation-induced defects including bubbles, cracks, precipitates and simultaneous recovery by the thermal energy generated with the increase of irradiation dose.

  9. Study on tribological properties of multi-layer surface texture on Babbitt alloys surface

    Science.gov (United States)

    Zhang, Dongya; Zhao, Feifei; Li, Yan; Li, Pengyang; Zeng, Qunfeng; Dong, Guangneng

    2016-12-01

    To improve tribological properties of Babbitt alloys, multi-layer surface texture consisted of the main grooves and secondary micro-dimples are fabricated on the Babbitt substrate through laser pulse ablation. The tribological behaviors of multi-layer surface texture are investigated using a rotating type pin-on-disc tribo-meter under variation sliding speeds, and the film pressure distributions on the textured surfaces are simulated using computational fluid dynamics (CFD) method for elucidating the possible mechanisms. The results suggest that: (i) the multi-layer surface texture can reduce friction coefficient of Babbitt alloy, which has lowest friction coefficient of 0.03, in case of the groove parameter of 300 μm width and 15% of area density; (ii) the improvement effect may be more sensitive to the groove area density and the siding speed, and the textured surface with lower area density has lower friction coefficient under high sliding speed. Based on the reasons of (i) the secondary micro-dimples on Babbitt alloy possesses a hydrophobicity surface and (ii) the CFD analysis indicates that main grooves enhancing hydrodynamic effect, thus the multi-layer surface texture is regarded as dramatically improve the lubricating properties of the Babbitt alloy.

  10. Self-cementitious properties of fly ashes from CFBC boilers co-firing coal and high-sulphur petroleum coke

    International Nuclear Information System (INIS)

    Sheng Guanghong; Li Qin; Zhai Jianping; Li Feihu

    2007-01-01

    Self-cementitious properties of fly ash from circulating fluidized bed combustion boiler co-firing coal and high-sulphur petroleum coke (CPFA) were investigated. CPFA was self-cementitious which was affected by its fineness and chemical compositions, especially the contents of SO 3 and free lime (f-CaO). Higher contents of SO 3 and f-CaO were beneficial to self-cementitious strength; the self-cementitious strength increases with a decrease of its 45 μm sieve residue. The expansive ratio of CPFA hardened paste was high because of generation of ettringite (AFt), which was influenced by its water to binder ratio (W/A), curing style and grinding of the ash. The paste cured in water had the highest expansive ratio, and grinding of CPFA was beneficial to its volume stability. The hydration products of CPFA detected by X-ray diffraction (XRD) and scanning electron microscopy (SEM) were portlandite, gypsum, AFt and hydrated calcium silicate (C-S-H)

  11. Effect of Surface Treatment on the Properties of Wool Fabric

    Science.gov (United States)

    Kan, C. W.; Yuen, C. W. M.; Chan, C. K.; Lau, M. P.

    Wool fiber is commonly used in textile industry, however, it has some technical problems which affect the quality and performance of the finished products such as felting shrinkage, handle, lustre, pilling, and dyeability. These problems may be attributed mainly in the presence of wool scales on the fiber surface. Recently, chemical treatments such as oxidation and reduction are the commonly used descaling methods in the industry. However, as a result of the pollution caused by various chemical treatments, physical treatment such as low temperature plasma (LTP) treatment has been introduced recently because it is similarly capable of achieving a comparable descaling effect. Most of the discussions on the applications of LTP treatment on wool fiber were focused on applying this technique for improving the surface wettability and shrink resistance. Meanwhile, little discussion has been made on the mechanical properties, thermal properties, and the air permeability. In this paper, wool fabric was treated with LTP treatment with the use of a non-polymerizing gas, namely oxygen. After the LTP treatment, the fabrics low-stress mechanical properties, air permeability, and thermal properties were evaluated and discussed.

  12. Surface effects on the mechanical properties of nanoporous materials

    International Nuclear Information System (INIS)

    Xia Re; Li Xide; Feng Xiqiao; Qin Qinghua; Liu Jianlin

    2011-01-01

    Using the theory of surface elasticity, we investigate the mechanical properties of nanoporous materials. The classical theory of porous materials is modified to account for surface effects, which become increasingly important as the characteristic sizes of microstructures shrink to nanometers. First, a refined Timoshenko beam model is presented to predict the effective elastic modulus of nanoporous materials. Then the surface effects on the elastic microstructural buckling behavior of nanoporous materials are examined. In particular, nanoporous gold is taken as an example to illustrate the application of the proposed model. The results reveal that both the elastic modulus and the critical buckling behavior of nanoporous materials exhibit a distinct dependence on the characteristic sizes of microstructures, e.g. the average ligament width.

  13. Surface effects on the mechanical properties of nanoporous materials

    Energy Technology Data Exchange (ETDEWEB)

    Xia Re [School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072 (China); Li Xide; Feng Xiqiao [AML, Department of Engineering Mechanics, Tsinghua University, Beijing 100084 (China); Qin Qinghua [School of Engineering, Australian National University, Canberra, ACT 0200 (Australia); Liu Jianlin, E-mail: fengxq@tsinghua.edu.cn [Department of Engineering Mechanics, China University of Petroleum, Qingdao 266555 (China)

    2011-07-01

    Using the theory of surface elasticity, we investigate the mechanical properties of nanoporous materials. The classical theory of porous materials is modified to account for surface effects, which become increasingly important as the characteristic sizes of microstructures shrink to nanometers. First, a refined Timoshenko beam model is presented to predict the effective elastic modulus of nanoporous materials. Then the surface effects on the elastic microstructural buckling behavior of nanoporous materials are examined. In particular, nanoporous gold is taken as an example to illustrate the application of the proposed model. The results reveal that both the elastic modulus and the critical buckling behavior of nanoporous materials exhibit a distinct dependence on the characteristic sizes of microstructures, e.g. the average ligament width.

  14. Concentration and distribution of heavy metals and radionuclides in topsoils from Middle Jiu Valley surface coal exploitations sourrounding area (Gorj County, Romania)

    Science.gov (United States)

    Corneanu, Mihaela; Corneanu, Gabriel; Lacatusu, Anca-Rovena; Cojocaru, Luminita; Butnariu, Monica

    2013-04-01

    Middle Jiu Valley is one of the largest surface coal exploitation area in Romania. The coal exploitation area is a dense populated one, along the valleys are villages and the inhabitants produce for their own consumption fruits and vegetables, in their personal gardens, or cereals in the fields, nearby the villages. There was considered to be of great interest to investigate the heavy metals and radionuclides content in gardens and cropfield soils from the villages sourrounding the Thermo Electric Power Plants (TEPP) and coal surface exploitation, as well as in crude /cultivated sterile soil or ash. The topsoil samples (104) were harvested from population gardens (58), cropfields sourronding Thermo Electric Power Plants (24), crude sterile dumps (7), cultivated sterile dumps (9) and ash dumps (6). The content in radionuclides in soil was performed by Duggan (1988) method. Radionuclide activity was expressed in Bqkg-1, confidence level 95%. The total content of heavy metals in soil (Zn, Cu, Fe, Mn, Pb, Cd, Ni, Cr, Co) was measured with flame atomic mass spectrometry. The content in heavy metals was expressed in mgkg-1. Soil analysis revealed the presence of natural radionuclides, beloging from ash and coal dust, as well as of Cs-137, of Cernobal provenance. In the cropfields radionuclides content in topsoil is lower than in gardens, due to the deepper soil mobilisation. Radionuclides content over the normal limits for Romania were registered for Th-234, Pb-210, U-235 and in few locations for Ra-226. The soil content for all analysed metals was over the normal limits in most samples, in few cases with values close to allert limits. Concentrations between allert and intervention limits were registered in samples collected from 15-20 km North of TEPP Turceni, in population gardens.

  15. Coal pump

    Science.gov (United States)

    Bonin, John H.; Meyer, John W.; Daniel, Jr., Arnold D.

    1983-01-01

    A device for pressurizing pulverized coal and circulating a carrier gas is disclosed. This device has utility in a coal gasification process and eliminates the need for a separate collection hopper and eliminates the separate compressor.

  16. Numerical investigation of heat transfer characteristics in utility boilers of oxy-coal combustion

    International Nuclear Information System (INIS)

    Hu, Yukun; Li, Hailong; Yan, Jinyue

    2014-01-01

    Highlights: • Air-coal and oxy-coal combustion in an industrial scale PF boiler were simulated in ANSYS FLUENT. • The O 2 concentration of 33 vol% in the oxy-coal combustion case matches the air-coal combustion case most closely. • The moisture in the flue gas has little impact on flame temperature, but positive impact on surface incident radiation. - Abstract: Oxy-coal combustion has different flue gas composition from the conventional air-coal combustion. The different composition further results in different properties, such as the absorption coefficient, emissivity, and density, which can directly affect the heat transfer in both radiation and convection zones of utility boilers. This paper numerically studied a utility boiler of oxy-coal combustion and compares with air-coal combustion in terms of flame profile and heat transferred through boiler side walls in order to understand the effects of different operating conditions on oxy-coal boiler retrofitting and design. Based on the results, it was found that around 33 vol% of effective O 2 concentration ([O 2 ] effective ) the highest flame temperature and total heat transferred through boiler side walls in the oxy-coal combustion case match to those in the air-coal combustion case most; therefore, the 33 vol% of [O 2 ] effective could result in the minimal change for the oxy-coal combustion retrofitting of the existing boiler. In addition, the increase of the moisture content in the flue gas has little impact on the flame temperature, but results in a higher surface incident radiation on boiler side walls. The area of heat exchangers in the boiler was also investigated regarding retrofitting. If boiler operates under a higher [O 2 ] effective , to rebalance the load of each heat exchanger in the boiler, the feed water temperature after economizer can be reduced or part of superheating surfaces can be moved into the radiation zone to replace part of the evaporators

  17. Hydrological properties of soils in reclaimed and unreclaimed sites after brown-coal mining

    Czech Academy of Sciences Publication Activity Database

    Cejpek, Jiří; Kuráž, V.; Frouz, J.

    2013-01-01

    Roč. 22, č. 3 (2013), s. 645-652 ISSN 1230-1485 R&D Projects: GA MŠk 2B08023 Grant - others:GAUK(CZ) 169410; GA ČR(CZ) GAP504/12/1288 Program:GA Institutional support: RVO:60077344 Keywords : physical properties * moisture regime * spoil heaps * reclaimed sites * unreclaimed sites Subject RIV: EH - Ecology, Behaviour Impact factor: 0.600, year: 2013

  18. ESTIMATION OF NEAR SUBSURFACE COAL FIRE GAS EMISSIONS BASED ON GEOPHYSICAL INVESTIGATIONS

    Science.gov (United States)

    Chen-Brauchler, D.; Meyer, U.; Schlömer, S.; Kus, J.; Gundelach, V.; Wuttke, M.; Fischer, C.; Rueter, H.

    2009-12-01

    Spontaneous and industrially caused subsurface coal fires are worldwide disasters that destroy coal resources, cause air pollution and emit a large amount of green house gases. Especially in developing countries, such as China, India and Malaysia, this problem has intensified over the last 15 years. In China alone, 10 to 20 million tons of coal are believed to be lost in uncontrolled coal fires. The cooperation of developing countries and industrialized countries is needed to enforce internationally concerted approaches and political attention towards the problem. The Clean Development Mechanism (CDM) under the framework of the Kyoto Protocol may provide an international stage for financial investment needed to fight the disastrous situation. A Sino-German research project for coal fire exploration, monitoring and extinction applied several geophysical approaches in order to estimate the annual baseline especially of CO2 emissions from near subsurface coal fires. As a result of this project, we present verifiable methodologies that may be used in the CDM framework to estimate the amount of CO2 emissions from near subsurface coal fires. We developed three possibilities to approach the estimation based on (1) thermal energy release, (2) geological and geometrical determinations as well as (3) direct gas measurement. The studies involve the investigation of the physical property changes of the coal seam and bedrock during different burning stages of a underground coal fire. Various geophysical monitoring methods were applied from near surface to determine the coal volume, fire propagation, temperature anomalies, etc.

  19. Surface properties of Ti-6Al-4V alloy part I: Surface roughness and apparent surface free energy

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Yingdi; Chibowski, Emil; Szcześ, Aleksandra, E-mail: aszczes@poczta.umcs.lublin.pl

    2017-01-01

    Titanium (Ti) and its alloys are the most often used implants material in dental treatment and orthopedics. Topography and wettability of its surface play important role in film formation, protein adhesion, following osseointegration and even duration of inserted implant. In this paper, we prepared Ti-6Al-4V alloy samples using different smoothing and polishing materials as well the air plasma treatment, on which contact angles of water, formamide and diiodomethane were measured. Then the apparent surface free energy was calculated using four different approaches (CAH, LWAB, O-W and Neumann's Equation of State). From LWAB approach the components of surface free energy were obtained, which shed more light on the wetting properties of samples surface. The surface roughness of the prepared samples was investigated with the help of optical profilometer and AFM. It was interesting whether the surface roughness affects the apparent surface free energy. It was found that both polar interactions the electron donor parameter of the energy and the work of water adhesion increased with decreasing roughness of the surfaces. Moreover, short time plasma treatment (1 min) caused decrease in the surface hydrophilic character, while longer time (10 min) treatment caused significant increase in the polar interactions and the work of water adhesion. Although Ti-6Al-4V alloy has been investigated many times, to our knowledge, so far no paper has been published in which surface roughness and changes in the surface free energy of the alloy were compared in the quantitative way in such large extent. This novel approach deliver better knowledge about the surface properties of differently smoothed and polished samples which may be helpful to facilitate cell adhesion, proliferation and mineralization. Therefore the results obtained present also potentially practical meaning. - Highlights: • Surface of five Ti-6Al-4V alloy samples were smoothed and polished successively. • The

  20. Characterization of Coal Porosity for Naturally Tectonically Stressed Coals in Huaibei Coal Field, China

    Science.gov (United States)

    Li, Xiaoshi; Hou, Quanlin; Li, Zhuo; Wei, Mingming

    2014-01-01

    The enrichment of coalbed methane (CBM) and the outburst of gas in a coal mine are closely related to the nanopore structure of coal. The evolutionary characteristics of 12 coal nanopore structures under different natural deformational mechanisms (brittle and ductile deformation) are studied using a scanning electron microscope (SEM) and low-temperature nitrogen adsorption. The results indicate that there are mainly submicropores (2~5 nm) and supermicropores (coal and mesopores (10~100 nm) and micropores (5~10 nm) in brittle deformed coal. The cumulative pore volume (V) and surface area (S) in brittle deformed coal are smaller than those in ductile deformed coal which indicates more adsorption space for gas. The coal with the smaller pores exhibits a large surface area, and coal with the larger pores exhibits a large volume for a given pore volume. We also found that the relationship between S and V turns from a positive correlation to a negative correlation when S > 4 m2/g, with pore sizes coal. The nanopore structure (coal. PMID:25126601

  1. Constraining the surface properties of effective Skyrme interactions

    Science.gov (United States)

    Jodon, R.; Bender, M.; Bennaceur, K.; Meyer, J.

    2016-08-01

    Background: Deformation energy surfaces map how the total binding energy of a nuclear system depends on the geometrical properties of intrinsic configurations, thereby providing a powerful tool to interpret nuclear spectroscopy and large-amplitude collective-motion phenomena such as fission. The global behavior of the deformation energy is known to be directly connected to the surface properties of the effective interaction used for its calculation. Purpose: The precise control of surface properties during the parameter adjustment of an effective interaction is key to obtain a reliable and predictive description of nuclear properties. The most relevant indicator is the surface-energy coefficient asurf. There are several possibilities for its definition and estimation, which are not fully equivalent and require a computational effort that can differ by orders of magnitude. The purpose of this study is threefold: first, to identify a scheme for the determination of asurf that offers the best compromise between robustness, precision, and numerical efficiency; second, to analyze the correlation between values for asurf and the characteristic energies of the fission barrier of 240Pu; and third, to lay out an efficient and robust procedure for how the deformation properties of the Skyrme energy density functional (EDF) can be constrained during the parameter fit. Methods: There are several frequently used possibilities to define and calculate the surface energy coefficient asurf of effective interactions built for the purpose of self-consistent mean-field calculations. The most direct access is provided by the model system of semi-infinite nuclear matter, but asurf can also be extracted from the systematics of binding energies of finite nuclei. Calculations can be carried out either self-consistently [Hartree-Fock (HF)], which incorporates quantal shell effects, or in one of the semiclassical extended Thomas-Fermi (ETF) or modified Thomas-Fermi (MTF) approximations. The

  2. Surface chemistry and bonding configuration of ultrananocrystalline diamond surfaces and their effects on nanotribological properties

    International Nuclear Information System (INIS)

    Sumant, A. V.; Grierson, D. S.; Carpick, R. W.; Gerbi, J. E.; Carlisle, J. A.; Auciello, O.

    2007-01-01

    We present a comprehensive study of surface composition and nanotribology for ultrananocrystalline diamond (UNCD) surfaces, including the influence of film nucleation on these properties. We describe a methodology to characterize the underside of the films as revealed by sacrificial etching of the underlying substrate. This enables the study of the morphology and composition resulting from the nucleation and initial growth of the films, as well as the characterization of nanotribological properties which are relevant for applications including micro-/nanoelectromechanical systems. We study the surface chemistry, bonding configuration, and nanotribological properties of both the topside and the underside of the film with synchrotron-based x-ray absorption near-edge structure spectroscopy to identify the bonding state of the carbon atoms, x-ray photoelectron spectroscopy to determine the surface chemical composition, Auger electron spectroscopy to further verify the composition and bonding configuration, and quantitative atomic force microscopy to study the nanoscale topography and nanotribological properties. The films were grown on SiO 2 after mechanically polishing the surface with detonation synthesized nanodiamond powder, followed by ultrasonication in a methanol solution containing additional nanodiamond powder. The sp 2 fraction, morphology, and chemistry of the as-etched underside are distinct from the topside, exhibiting a higher sp 2 fraction, some oxidized carbon, and a smoother morphology. The nanoscale single-asperity work of adhesion between a diamond nanotip and the as-etched UNCD underside is far lower than for a silicon-silicon interface (59.2±2 vs 826±186 mJ/m 2 , respectively). Exposure to atomic hydrogen dramatically reduces nanoscale adhesion to 10.2±0.4 mJ/m 2 , at the level of van der Waals' interactions and consistent with recent ab initio calculations. Friction is substantially reduced as well, demonstrating a direct link between the

  3. Formation and filtration of flakes from coal slurries

    Energy Technology Data Exchange (ETDEWEB)

    Sing, B K; Clement, M; Juentgen, H

    1977-06-01

    Size and size distribution of flakes are much influenced by the type and concentration of the flocculation agent. The coal particles show different behaviour to that of the dirt particles. The ph-value and the concentration of electrolytes also influence flocculation. They change the surface properties of the solid material as well as the flocculability of the flocculant.

  4. Investigation on CO2 property and its geological disposal in coal bed

    International Nuclear Information System (INIS)

    Liang Weiguo; Wu Di; Hao Shuping

    2008-01-01

    Carbon dioxide is main green house gas, and it has been increased greatly in the atmosphere since the industrial revolution. The human living environment has been worsened with more and more carbon dioxide in the air. In this paper, the authors analyzed the physical property of carbon dioxide and green house gas effect, then studied the disposal measures for carbon dioxide. At last it was pointed out that various measures should be taken to carry out the carbon dioxide disposal, more economic benefit can be anticipated along with carbon dioxide disposal by EOR, CO 2 -ECBM, CAES, et al, of which CO 2 -ECBM is one of the way with best benefits. (authors)

  5. Influence of surface roughness on the friction property of textured surface

    Directory of Open Access Journals (Sweden)

    Yuankai Zhou

    2015-02-01

    Full Text Available In contrast with dimple textures, surface roughness is a texture at the micro-scale, essentially which will influence the load-bearing capacity of lubricant film. The numerical simulation was carried out to investigate the influence of surface roughness on friction property of textured surface. The lubricant film pressure was obtained using the method of computational fluid dynamics according to geometric model of round dimple, and the renormalization-group k–ε turbulent model was adopted in the computation. The numerical simulation results suggest that there is an optimum dimensionless surface roughness, and near this value, the maximum load-bearing capacity can be achieved. The load-bearing capacity is determined by the surface texture, the surface roughness, and the interaction between them. To get information of friction coefficient, the experiments were conducted. This experiment was used to evaluate the simulation. The experimental results show that for the frequency of 4 and 6 Hz, friction coefficient decreases at first and then increases with decreasing surface roughness, which indicates that there exists the optimum region of surface roughness leading to the best friction reduction effect, and it becomes larger when area fractions increase from 2% to 10%. The experimental results agree well with the simulation results.

  6. Changes in surface properties caused by ion implantation

    International Nuclear Information System (INIS)

    Iwaki, Masaya

    1987-01-01

    This report outlines various aspects of ion implantation. Major features of ion implantation are described first, focusing on the structure of ion implantation equipment and some experimental results of ion implantation into semiconductors. Distribution of components in ion-implantated layers is then discussed. The two major features of ion implantation in relation to the distribution of implanted ions are: (1) high controllability of addition of ions to a surface layer and (2) formation of a large number of lattice defects in a short period of time. Application of ion implantation to metallic materials is expected to permit the following: (1) formation of a semi-stable alloy surface layer by metallic ion implantation, (2) formation of a semi-stable ceramic surface layer or buried layer by non-metallic ion implantation, and (3) formation of a buried layer by combined implementation of a different metallic ion and non-metallic ion. Ion implantation in carbon materials, polymers and ceramics is discussed next. The last part of the report is dedicated to macroscopic properties of an ion-implanted layer, centering on surface modification, formation of a conductive surface layer, and tribology. (Nogami, K.) 60 refs

  7. Bio-coal briquettes using low-grade coal

    Science.gov (United States)

    Estiaty, L. M.; Fatimah, D.; Widodo

    2018-02-01

    The technology in using briquettes for fuel has been widely used in many countries for both domestic and industrial purposes. Common types of briquette used are coal, peat, charcoal, and biomass. Several researches have been carried out in regards to the production and the use of briquettes. Recently, researches show that mixing coal and biomass will result in an environmentally friendly briquette with better combustion and physical characteristics. This type of briquette is known as bio-coal briquettes. Bio-coal briquettes are made from agriculture waste and coal, which are readily available, cheap and affordable. Researchers make these bio-coal briquettes with different aims and objectives, depending on the issues to address, e.g. utilizing agricultural waste as an alternative energy to replace fossil fuels that are depleting its reserves, adding coal to biomass in order to add calorific value to bio-coal briquette, and adding biomass to coal to improve its chemical and physical properties. In our research, biocoal briquettes are made to utilize low grade coal. The biomass we use, however, is different from the ones used in past researches because it has undergone fermentation. The benefits of using such biomass are 1. Fermentation turns the hemi cellulose into a simpler form, so that the burning activation energy decreases while the calorific value increases. 2. Enzym produced will bind to heavy metals from coal as co-factors, forming metals that are environmentally friendly.

  8. The influence of the fault zone width on land surface vibrations after the high-energy tremor in the "Rydułtowy-Anna" hard coal mine

    Science.gov (United States)

    Pilecka, Elżbieta; Szwarkowski, Dariusz

    2018-04-01

    In the article, a numerical analysis of the impact of the width of the fault zone on land surface tremors on the area of the "Rydułtowy - Anna" hard coal mine was performed. The analysis covered the dynamic impact of the actual seismic wave after the high-energy tremor of 7 June 2013. Vibrations on the land surface are a measure of the mining damage risk. It is particularly the horizontal components of land vibrations that are dangerous to buildings which is reflected in the Mining Scales of Intensity (GSI) of vibrations. The run of a seismic wave in the rock mass from the hypocenter to the area's surface depends on the lithology of the area and the presence of fault zones. The rock mass network cut by faults of various widths influences the amplitude of tremor reaching the area's surface. The analysis of the impact of the width of the fault zone was done for three alternatives.

  9. Seismic characterization of CO{sub 2} in coals

    Energy Technology Data Exchange (ETDEWEB)

    McCrank, J.; Lawton, D.C. [Calgary Univ., AB (Canada). Dept. of Geoscience, Consortium for Research in Elastic Wave Exploration Seismology

    2008-07-01

    The Mynheer coal seam was targeted for an enhanced coalbed methane (CBM) experiment. During initial testing of the reservoir permeability, 180 tonnes of carbon dioxide (CO{sub 2}) was injected into the seam. The objective of the study was to characterize the coal zones and to determine if the small volume of CO{sub 2} in the thinly bedded and seismically tuned reservoir can be detected in the 3D surface seismic data. The multi-well pilot project took place in the Pembina Field of west-central Alberta. The Ardley coals were tested for CO{sub 2} injection, enhanced CBM production, and CO{sub 2} sequestration. The seismic survey captured the condition of the reservoir after formation permeability tests. It was concluded that the anomalies seen in the seismic data can be attributed to changes in the physical properties of the coal due to CO{sub 2} adsorption. 2 refs., 5 figs.

  10. Magnetic nanoparticles: surface effects and properties related to biomedicine applications.

    Science.gov (United States)

    Issa, Bashar; Obaidat, Ihab M; Albiss, Borhan A; Haik, Yousef

    2013-10-25

    Due to finite size effects, such as the high surface-to-volume ratio and different crystal structures, magnetic nanoparticles are found to exhibit interesting and considerably different magnetic properties than those found in their corresponding bulk materials. These nanoparticles can be synthesized in several ways (e.g., chemical and physical) with controllable sizes enabling their comparison to biological organisms from cells (10-100 μm), viruses, genes, down to proteins (3-50 nm). The optimization of the nanoparticles' size, size distribution, agglomeration, coating, and shapes along with their unique magnetic properties prompted the application of nanoparticles of this type in diverse fields. Biomedicine is one of these fields where intensive research is currently being conducted. In this review, we will discuss the magnetic properties of nanoparticles which are directly related to their applications in biomedicine. We will focus mainly on surface effects and ferrite nanoparticles, and on one diagnostic application of magnetic nanoparticles as magnetic resonance imaging contrast agents.

  11. Investigation of CVD graphene topography and surface electrical properties

    International Nuclear Information System (INIS)

    Wang, Rui; Pearce, Ruth; Gallop, John; Patel, Trupti; Pollard, Andrew; Hao, Ling; Zhao, Fang; Jackman, Richard; Klein, Norbert; Zurutuza, Amaia

    2016-01-01

    Combining scanning probe microscopy techniques to characterize samples of graphene, a selfsupporting, single atomic layer hexagonal lattice of carbon atoms, provides far more information than a single technique can. Here we focus on graphene grown by chemical vapour deposition (CVD), grown by passing carbon containing gas over heated copper, which catalyses single atomic layer growth of graphene on its surface. To be useful for applications the graphene must be transferred onto other substrates. Following transfer it is important to characterize the CVD graphene. We combine atomic force microscopy (AFM) and scanning Kelvin probe microscopy (SKPM) to reveal several properties of the transferred film. AFM alone provides topographic information, showing ‘wrinkles’ where the transfer provided incomplete substrate attachment. SKPM measures the surface potential indicating regions with different electronic properties for example graphene layer number. By combining AFM and SKPM local defects and impurities can also be observed. Finally, Raman spectroscopy can confirm the structural properties of the graphene films, such as the number of layers and level of disorder, by observing the peaks present. We report example data on a number of CVD samples from different sources. (paper)

  12. Coal Calorific Value Prediction Based on Projection Pursuit Principle

    OpenAIRE

    QI Minfang; FU Zhongguang; JING Yuan

    2012-01-01

    The calorific value of coal is an important factor for the economic operation of coal-fired power plant. However, calorific value is tremendous difference between the different coal, and even if coal is from the same mine. Restricted by the coal market, most of coal fired power plants can not burn the designed-coal by now in China. The properties of coal as received are changing so frequently that pulverized coal firing is always with the unexpected condition. Therefore, the researches on the...

  13. Formation and retention of methane in coal

    Energy Technology Data Exchange (ETDEWEB)

    Hucka, V.J.; Bodily, D.M.; Huang, H.

    1992-05-15

    The formation and retention of methane in coalbeds was studied for ten Utah coal samples, one Colorado coal sample and eight coal samples from the Argonne Premium Coal Sample Bank.Methane gas content of the Utah and Colorado coals varied from zero to 9 cm{sup 3}/g. The Utah coals were all high volatile bituminous coals. The Colorado coal was a gassy medium volatile bituminous coal. The Argonne coals cover a range or rank from lignite to low volatile bituminous coal and were used to determine the effect of rank in laboratory studies. The methane content of six selected Utah coal seams and the Colorado coal seam was measured in situ using a special sample collection device and a bubble desorbometer. Coal samples were collected at each measurement site for laboratory analysis. The cleat and joint system was evaluated for the coal and surrounding rocks and geological conditions were noted. Permeability measurements were performed on selected samples and all samples were analyzed for proximate and ultimate analysis, petrographic analysis, {sup 13}C NMR dipolar-dephasing spectroscopy, and density analysis. The observed methane adsorption behavior was correlated with the chemical structure and physical properties of the coals.

  14. Tribological properties of nanostripe surface structures-a design concept for improving tribological properties

    International Nuclear Information System (INIS)

    Miyake, K; Nakano, M; Korenaga, A; Mano, H; Ando, Y

    2010-01-01

    The tribological properties of nanostripe surface structures were investigated using a pin-on-plate tribometer in order to propose a design concept for improving the tribological properties. The authors used four kinds of nanostripe structures consisting of different combinations of materials (Fe-Au, C-SiC, Al-Al 2 O 3 and Al-Pt) fabricated by a process they had previously proposed. The frictional properties of the nanostripe structures depended on the materials that constituted the nanostripes. When the sliding direction in friction tests was parallel to the microgrooves, nanostripe structures remained on all surfaces even after friction tests. Based on the friction test results, the authors considered a design concept for nanostripe structures in tribological applications.

  15. A coal combine

    Energy Technology Data Exchange (ETDEWEB)

    Wlachovsky, I; Bartos, J

    1980-02-15

    A design is presented for a coal combine, equipped with two drum operational units, on whose both ends of the upper surface of the body, two coal saws are mounted with the help of a lever system. These saws, found in an operational position, form a gap in the block of the coal block, which is not embraced by the drum operational unit. The coal block, found between the gap and the support, falls down onto the longwall scraper conveyor. The lever system of each coal saw is controlled by two hydraulic jacks. One of the jacks is mounted vertically on the facial wall of the body of the combine and is used for the hoisting for the required height of the horizontal arm of the lever, reinforced by one end in the hinge on the body of the combine. On the ''free'' end of that lever, a coal saw is mounted in a hinge-like fashion and which is connected by the hydraulic jack to the horizontal arm of the lever system. This hydraulic jack is used for the clamping of the coal saw to the face.

  16. Near surface mechanical properties of optical single crystals and surface response to deterministic microgrinding

    Science.gov (United States)

    Randi, Joseph A., III

    2005-12-01

    This thesis makes use of microindentation, nanoindentation and nanoscratching methods to better understand the mechanical properties of single crystalline silicon, calcium fluoride, and magnesium fluoride. These properties are measured and are used to predict the material's response to material removal, specifically by grinding and polishing, which is a combination of elastic, plastic and fracture processes. The hardness anisotropy during Knoop microindentation, hardness from nanoindentation, and scratch morphology from nanoscratching are reported. This information is related to the surface microroughness from grinding. We show that mechanical property relationships that predict the surface roughness from lapping and deterministic microgrinding of optical glasses are applicable to single crystals. We show the range of hardness from some of the more common crystallographic faces. Magnesium fluoride, having a tetragonal structure, has 2-fold hardness anisotropy. Nanoindentation, as expected provides higher hardness than microindentation, but anisotropy is not observed. Nanoscratching provides the scratch profile during loading, after the load has been removed, and the coefficient of friction during the loading. Ductile and brittle mode scratching is present with brittle mode cracking being orientation specific. Subsurface damage (SSD) measurements are made using a novel process known as the MRF technique. Magnetorheological finishing is used to polish spots into the ground surface where SSD can be viewed. SSD is measured using an optical microscope and knowledge of the spot profile. This technique is calibrated with a previous technique and implemented to accurately measure SSD in single crystals. The data collected are compared to the surface microroughness of the ground surface, resulting in an upper bound relationship. The results indicate that SSD is always less than 1.4 times the peak-to-valley surface microroughness for single crystals regardless of the

  17. Effects of potential surface coal mining on dissolved solids in Otter Creek and in the Otter Creek alluvial aquifer, southeastern Montana

    Science.gov (United States)

    Cannon, M.R.

    1985-01-01

    Otter Creek drains an area of 709 square miles in the coal-rich Powder River structural basin of southeastern Montana. The Knobloch coal beds in the Tongue River Member of the Paleocene Fort Union Formation is a shallow aquifer and a target for future surface mining in the downstream part of the Otter Creek basin. A mass-balance model was used to estimate the effects of potential mining on the dissolved solids concentration in Otter Creek and in the alluvial aquifer in the Otter Creek valley. With extensive mining of the Knobloch coal beds, the annual load of dissolved solids to Otter Creek at Ashland at median streamflow could increase by 2,873 tons, or a 32-percent increase compared to the annual pre-mining load. Increased monthly loads of Otter Creek, at the median streamflow, could range from 15 percent in February to 208 percent in August. The post-mining dissolved solids load to the subirrigated part of the alluvial valley could increase by 71 percent. The median dissolved solids concentration in the subirrigated part of the valley could be 4,430 milligrams per liter, compared to the pre-mining median concentration of 2,590 milligrams per liter. Post-mining loads from the potentially mined landscape were calculated using saturated-paste-extract data from 506 overburdened samples collected from 26 wells and test holes. Post-mining loads to the Otter Creek valley likely would continue at increased rates for hundreds of years after mining. If the actual area of Knobloch coal disturbed by mining were less than that used in the model, post-mining loads to the Otter Creek valley would be proportionally smaller. (USGS)

  18. Nonlinear mean field theory for nuclear matter and surface properties

    International Nuclear Information System (INIS)

    Boguta, J.; Moszkowski, S.A.

    1983-01-01

    Nuclear matter properties are studied in a nonlinear relativistic mean field theory. We determine the parameters of the model from bulk properties of symmetric nuclear matter and a reasonable value of the effective mass. In this work, we stress the nonrelativistic limit of the theory which is essentially equivalent to a Skyrme hamiltonian, and we show that most of the results can be obtained, to a good approximation, analytically. The strength of the required parameters is determined from the binding energy and density of nuclear matter and the effective nucleon mass. For realistic values of the parameters, the nonrelativistic approximation turns out to be quite satisfactory. Using reasonable values of the parameters, we can account for other key properties of nuclei, such as the spin-orbit coupling, surface energy, and diffuseness of the nuclear surface. Also the energy dependence of the nucleon-nucleus optical model is accounted for reasonably well except near the Fermi surface. It is found, in agreement with empirical results, that the Landau parameter F 0 is quite small in normal nuclear matter. Both density dependence and momentum dependence of the NN interaction, but especially the former, are important for nuclear saturation. The required scalar and vector coupling constants agree fairly well with those obtained from analyses of NN scattering phase shifts with one-boson-exchange models. The mean field theory provides a semiquantitative justification for the weak Skyrme interaction in odd states. The strength of the required nonlinear term is roughly consistent with that derived using a new version of the chiral mean field theory in which the vector mass as well as the nucleon mass is generated by the sigma-field. (orig.)

  19. Microstructure and surface mechanical properties of pulse electrodeposited nickel

    Energy Technology Data Exchange (ETDEWEB)

    Ul-Hamid, A., E-mail: anwar@kfupm.edu.sa [Center of Research Excellence in Corrosion (CoRE-C), Research Institute, King Fahd University of Petroleum and Minerals, P.O. Box 1073, Dhahran 31261 (Saudi Arabia); Dafalla, H.; Quddus, A.; Saricimen, H.; Al-Hadhrami, L.M. [Center of Research Excellence in Corrosion (CoRE-C), Research Institute, King Fahd University of Petroleum and Minerals, P.O. Box 1073, Dhahran 31261 (Saudi Arabia)

    2011-09-01

    The surface of carbon steel was modified by electrochemical deposition of Ni in a standard Watt's bath using dc and pulse plating electrodeposition. The aim was to compare the microstructure and surface mechanical properties of the deposit obtained by both techniques. Materials characterization was conducted using field emission scanning electron microscope fitted with scanning transmission electron detector, atomic force microscope and X-ray diffractometer. Nanoindentation hardness, elastic modulus, adhesion, coefficients of friction and wear rates were determined for both dc and pulse electrodeposits. Experimental results indicate that pulse electrodeposition produced finer Ni grains compared to dc plating. Size of Ni grains increased with deposition. Both dc and pulse deposition resulted in grain growth in preferred (2 0 0) orientation. However, presence of Ni (1 1 1) grains increased in deposits produced by pulse deposition. Pulse plated Ni exhibited higher hardness, creep and coefficient of friction and lower modulus of elasticity compared to dc plated Ni.

  20. Effect of nanofillers' size on surface properties after toothbrush abrasion.

    Science.gov (United States)

    Cavalcante, Larissa M; Masouras, Konstantinos; Watts, David C; Pimenta, Luiz A; Silikas, Nick

    2009-02-01

    To investigate the effect of filler-particle size of experimental and commercial resin composites, undergoing toothbrush abrasion, on three surface properties: surface roughness (SR), surface gloss (G) and color stability (CS). Four model (Ivoclar/Vivadent) and one commercial resin composite (Tokuyama) with varying filler-size from 100-1000 nm were examined. Six discs (10 mm x 2 mm) from each product were prepared and mechanically polished. The samples were then submitted to 20,000 brushing strokes in a toothbrush abrasion machine. SR parameters (Ra, Rt and RSm), G, and CS were measured before and after toothbrush abrasion. Changes in SR and G were analyzed by 2-way ANOVA, with Bonferroni post hoc test. CS values were submitted to one-way ANOVA and Bonferroni post hoc test (alpha=0.05). Initial G values ranged between 73-87 gloss units (GU) and were reduced after toothbrush abrasion to a range of 8-64 GU. Toothbrush abrasion resulted in significant modifications in SR and G amongst the materials tested, attributed to filler sizes. There was statistically significant difference in color (delta E* ranged from 0.38-0.88). Filler size did not affect color stability. Toothbrush abrasion resulted in rougher and matte surfaces for all materials tested. Although the individual differences in surface roughness among filler sizes were not always significant, the correlation showed a trend that larger filler sizes resulted in higher surface roughness after abrasion for the SR parameters Ra and Rt (r = 0.95; r = 0.93, respectively). RSm showed an increase after toothbrush abrasion for all resin composites, however no significant correlation was detected (r = 0.21).There was a significant correlation between G and Ra ratios (r = - 0.95).

  1. Topological Characterization of Fractured Coal

    Science.gov (United States)

    Jing, Yu; Armstrong, Ryan T.; Ramandi, Hamed L.; Mostaghimi, Peyman

    2017-12-01

    Coal transport properties are highly dependent on the underlying fractured network, known as cleats, which are characterized by geometrical and topological properties. X-ray microcomputed tomography (micro-CT) has been widely applied to obtain 3-D digital representations of the cleat network. However, segmentation of 3-D data is often problematic due to image noise, which will result in inaccurate estimation of coal properties (e.g., porosity and specific surface area). To circumvent this issue, a discrete fracture network (DFN) model is proposed. We develop a characterization framework to determine if the developed DFN models can preserve the topological properties of the coal cleat network found in micro-CT data. We compute the Euler characteristic, fractal dimension, and percolation quantities to analyze the topology locally and globally and compare the results between micro-CT data (before denoising), filtered micro-CT data (after denoising), and the DFN model. We find that micro-CT data with noise have extensive connectivity while filtered micro-CT data and DFN models have similar topology both globally and locally. It is concluded that the topology of the DFN models are closer to that of the realistic cleat network that do not have segmentation-induced pores. In addition, micro-CT imaging always struggles with the trade-off between sample size and resolution, while the presented DFN models are not restricted by imaging resolution and thus can be constructed with extended domain size. Overall, the presented DFN model is a reliable alternative with realistic cleat topology, extended domain size and favorable data format for direct numerical simulations.

  2. Modification of polyvinyl alcohol surface properties by ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Pukhova, I.V., E-mail: ivpuhova@mail.ru [National Research Tomsk State University, 36 Lenin Ave, Tomsk 634050 (Russian Federation); Institute of High Current Electronics, 2/3 Akademichesky Ave, Tomsk 634055 (Russian Federation); Kurzina, I.A. [National Research Tomsk State University, 36 Lenin Ave, Tomsk 634050 (Russian Federation); Savkin, K.P. [Institute of High Current Electronics, 2/3 Akademichesky Ave, Tomsk 634055 (Russian Federation); Laput, O.A. [National Research Tomsk Polytechnic University, 30 Lenin Ave, Tomsk 634050 (Russian Federation); Oks, E.M. [Institute of High Current Electronics, 2/3 Akademichesky Ave, Tomsk 634055 (Russian Federation)

    2017-05-15

    We describe our investigations of the surface physicochemical properties of polyvinyl alcohol modified by silver, argon and carbon ion implantation to doses of 1 × 10{sup 14}, 1 × 10{sup 15} and 1 × 10{sup 16} ion/cm{sup 2} and energies of 20 keV (for C and Ar) and 40 keV (for Ag). Infrared spectroscopy (IRS) indicates that destructive processes accompanied by chemical bond (−C=O) generation are induced by implantation, and X-ray photoelectron spectroscopy (XPS) analysis indicates that the implanted silver is in a metallic Ag3d state without stable chemical bond formation with polymer chains. Ion implantation is found to affect the surface energy: the polar component increases while the dispersion part decreases with increasing implantation dose. Surface roughness is greater after ion implantation and the hydrophobicity increases with increasing dose, for all ion species. We find that ion implantation of Ag, Ar and C leads to a reduction in the polymer microhardness by a factor of five, while the surface electrical resistivity declines modestly.

  3. Properties of bare strange stars associated with surface electric fields

    International Nuclear Information System (INIS)

    Picanco Negreiros, Rodrigo; Mishustin, Igor N.; Schramm, Stefan; Weber, Fridolin

    2010-01-01

    In this paper we investigate the electrodynamic surface properties of bare strange quark stars. The surfaces of such objects are characterized by the formation of ultrahigh electric surface fields which might be as high as ∼10 19 V/cm. These fields result from the formation of electric dipole layers at the stellar surfaces. We calculate the increase in gravitational mass associated with the energy stored in the electric dipole field, which turns out to be only significant if the star possesses a sufficiently strong net electric charge distribution. In the second part of the paper, we explore the intriguing possibility of what happens when the electron layer (sphere) rotates with respect to the stellar strange matter body. We find that in this event magnetic fields can be generated which, for moderate effective rotational frequencies between the electron layer and the stellar body, agree with the magnetic fields inferred for several central compact objects. These objects could thus be comfortably interpreted as strange stars whose electron atmospheres rotate at frequencies that are moderately different (∼10 Hz) from the rotational frequencies of the strange star itself.

  4. Engineered Surface Properties of Porous Tungsten from Cryogenic Machining

    Science.gov (United States)

    Schoop, Julius Malte

    Porous tungsten is used to manufacture dispenser cathodes due to it refractory properties. Surface porosity is critical to functional performance of dispenser cathodes because it allows for an impregnated ceramic compound to migrate to the emitting surface, lowering its work function. Likewise, surface roughness is important because it is necessary to ensure uniform wetting of the molten impregnate during high temperature service. Current industry practice to achieve surface roughness and surface porosity requirements involves the use of a plastic infiltrant during machining. After machining, the infiltrant is baked and the cathode pellet is impregnated. In this context, cryogenic machining is investigated as a substitutionary process for the current plastic infiltration process. Along with significant reductions in cycle time and resource use, surface quality of cryogenically machined un-infiltrated (as-sintered) porous tungsten has been shown to significantly outperform dry machining. The present study is focused on examining the relationship between machining parameters and cooling condition on the as-machined surface integrity of porous tungsten. The effects of cryogenic pre-cooling, rake angle, cutting speed, depth of cut and feed are all taken into consideration with respect to machining-induced surface morphology. Cermet and Polycrystalline diamond (PCD) cutting tools are used to develop high performance cryogenic machining of porous tungsten. Dry and pre-heated machining were investigated as a means to allow for ductile mode machining, yet severe tool-wear and undesirable smearing limited the feasibility of these approaches. By using modified PCD cutting tools, high speed machining of porous tungsten at cutting speeds up to 400 m/min is achieved for the first time. Beyond a critical speed, brittle fracture and built-up edge are eliminated as the result of a brittle to ductile transition. A model of critical chip thickness ( hc ) effects based on cutting

  5. Surface orientation effects on bending properties of surgical mesh are independent of tensile properties.

    Science.gov (United States)

    Simon, David D; Andrews, Sharon M; Robinson-Zeigler, Rebecca; Valdes, Thelma; Woods, Terry O

    2018-02-01

    Current mechanical testing of surgical mesh focuses primarily on tensile properties even though implanted devices are not subjected to pure tensile loads. Our objective was to determine the flexural (bending) properties of surgical mesh and determine if they correlate with mesh tensile properties. The flexural rigidity values of 11 different surgical mesh designs were determined along three textile directions (machine, cross-machine, and 45° to machine; n = 5 for each) using ASTM D1388-14 while tracking surface orientation. Tensile testing was also performed on the same specimens using ASTM D882-12. Linear regressions were performed to compare mesh flexural rigidity to mesh thickness, areal mass density, filament diameter, ultimate tensile strength, and maximum extension. Of 33 mesh specimen groups, 30 had significant differences in flexural rigidity values when comparing surface orientations (top and bottom). Flexural rigidity and mesh tensile properties also varied with textile direction (machine and cross-machine). There was no strong correlation between the flexural and tensile properties, with mesh thickness having the best overall correlation with flexural rigidity. Currently, surface orientation is not indicated on marketed surgical mesh, and a single mesh may behave differently depending on the direction of loading. The lack of correlation between flexural stiffness and tensile properties indicates the need to examine mesh bending stiffness to provide a more comprehensive understanding of surgical mesh mechanical behaviors. Further investigation is needed to determine if these flexural properties result in the surgical mesh behaving mechanically different depending on implantation direction. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 854-862, 2018. © 2017 Wiley Periodicals, Inc.

  6. Influence of pore structure and chemical properties of supported Mo catalysts on their performance in upgrading heavy coal liquids

    Energy Technology Data Exchange (ETDEWEB)

    Song, C.; Hanaoka, K.; Nomura, M. (Pennsylvania State University, University Park, PA (USA). Dept. of Materials Science and Engineering)

    In the hydroprocessing of solvent-refined coals, both the pore structure and the chemical properties of the catalysts affect the conversion of the heavy materials. Increasing median pore diameter (MPD) of unimodal Ni-Mo/Al[sub 2]O[sub 3] catalysts in the relatively small pore region (up to 150 [angstrom]) enhanced the conversion of both asphaltene and preasphaltene, but further increasing the MPD up to 730 [angstrom] mainly promoted preasphaltene conversion. In the runs of the isolated fractions, however, conversions increased with MPD up to 290 [angstrom] for asphaltene and up to 730 [angstrom] for preasphaltene. The degree of heteroatom removal is also influenced by MPD. There exist preferable pore size ranges for hydrodeoxygenation. Two Mo/SiO[sub 2] and several carbon-coated Ni-Mo/Al[sub 2]O[sub 3] catalysts with different MPD and a commercial Ni-Mo supported on silicated Al[sub 2]O[sub 3] were also compared. The increasing MPD of SiO[sub 2]-supported Mo catalysts increased the conversion of preasphaltene materials. Mo/SiO[sub 2] catalysts are more effective than Ni-Mo supported on Al[sub 2]O[sub 3] and silicated Al[sub 2]O[sub 3] for converting preasphaltene materials, while the latter two are more active for conversion of asphaltene into oil. Another interesting observation is that, for a given MPD range, the carbon-coated Ni-Mo/Al[sub 2]O[sub 3] catalysts gave higher preasphaltene conversions than fresh ones. These results point to the conclusion that larger pore and less acidic hydrogenation catalysts are more effective for preasphaltene conversion, but efficient conversion of asphaltene into oil is facilitated by mild hydrocracking catalysts having appropriate pore size ranges. 43 refs., 8 figs., 9 tabs.

  7. The effect of CO{sub 2} saturation on mechanical properties of Australian black coal using acoustic emission

    Energy Technology Data Exchange (ETDEWEB)

    P.G. Ranjit; D. Jasinge; S.K. Choi; M. Mehic; B. Shannon [Monash University (Australia). Department of Civil Engineering

    2010-08-15

    Acoustic emission (AE) methods are now widely used for damage evaluation. For a better understanding of the damage mechanics of materials such as rocks, AE has been used to monitor stresses which induce crack closure, crack initiation and crack damage. In the present study, an AE system was used to study the damage behaviour of some Australian black coal samples subjected to uniaxial compression. Several samples were left in a container filled with 100% carbon dioxide (CO{sub 2}) at a certain pressure for 72 h prior to testing. The results were compared with samples which had only been exposed to the atmosphere to see if CO{sub 2} had any adverse effect on the strength of coal. Strain gauges were installed on the samples and the measured axial and volumetric strains were studied in conjunction with the AE counts. The AE method was successfully used for detecting the onset of crack initiation and the crack damage stress threshold of the black coal samples. Of the coal samples examined, crack initiation and crack closure of the samples subjected to saturation with CO{sub 2} occurred at stress corresponding to a higher percentage of the peak strength when compared to the samples which had only been exposed to atmospheric conditions. However, crack damage occurred at a higher percentage of peak strength and the average peak strength showed a higher value for samples in atmospheric condition when compared to CO{sub 2} saturated samples. The results show that sorption of CO{sub 2} can cause a reduction in strength of the black coal samples when tested under uniaxial compression. As the coal samples were highly inhomogeneous more tests are required in order to be able to confirm whether the adsorption of CO{sub 2} will cause strength reduction in coal and to identify the actual underlying mechanisms. 36 refs., 8 figs., 2 tabs.

  8. Electronic properties of semiconductor surfaces and metal/semiconductor interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Tallarida, M.

    2005-05-15

    This thesis reports investigations of the electronic properties of a semiconductor surface (silicon carbide), a reactive metal/semiconductor interface (manganese/silicon) and a non-reactive metal/semiconductor interface (aluminum-magnesium alloy/silicon). The (2 x 1) reconstruction of the 6H-SiC(0001) surface has been obtained by cleaving the sample along the (0001) direction. This reconstruction has not been observed up to now for this compound, and has been compared with those of similar elemental semiconductors of the fourth group of the periodic table. This comparison has been carried out by making use of photoemission spectroscopy, analyzing the core level shifts of both Si 2p and C 1s core levels in terms of charge transfer between atoms of both elements and in different chemical environments. From this comparison, a difference between the reconstruction on the Si-terminated and the C-terminated surface was established, due to the ionic nature of the Si-C bond. The growth of manganese films on Si(111) in the 1-5 ML thickness range has been studied by means of LEED, STM and photoemission spectroscopy. By the complementary use of these surface science techniques, two different phases have been observed for two thickness regimes (<1 ML and >1 ML), which exhibit a different electronic character. The two reconstructions, the (1 x 1)-phase and the ({radical}3 x {radical}3)R30 -phase, are due to silicide formation, as observed in core level spectroscopy. The growth proceeds via island formation in the monolayer regime, while the thicker films show flat layers interrupted by deep holes. On the basis of STM investigations, this growth mode has been attributed to strain due to lattice mismatch between the substrate and the silicide. Co-deposition of Al and Mg onto a Si(111) substrate at low temperature (100K) resulted in the formation of thin alloy films. By varying the relative content of both elements, the thin films exhibited different electronic properties

  9. Effects of a Chitosan Coating Layer on the Surface Properties and Barrier Properties of Kraft Paper

    Directory of Open Access Journals (Sweden)

    Shanhui Wang

    2016-01-01

    Full Text Available Biodegradable chitosan can be applied as a coating on the surface of kraft paper in order to improve its barrier properties against water vapor and air. The food packaging industry can benefit from the addition of chitosan to its current packaging, and in turn reduce pollution from plastic packaging plants. This paper discusses the film formation of chitosan, the permeability of paper coated with a chitosan layer, and the influence on the paper’s surface and barrier properties under different process conditions. SEM (scanning electron microscope, AFM (atomic force microscope, ATR-FTIR (Fourier transmission infrared spectroscope with attenuated total reflection, and PDA (penetration dynamics analysis were used to analyze the properties of chitosan’s film formation and permeability. A controlled experiment showed that the chitosan layer was smoother than the surface of the uncoated kraft paper, had better film formation, and that there was no chitosan penetration through the kraft paper. The barrier properties against water vapor were strongest when there was a higher concentration of chitosan solution at the optimum pH, stirring speed, and those with a thicker coating on the kraft paper.

  10. Surface ferromagnetism and superconducting properties of nanocrystalline niobium nitride

    International Nuclear Information System (INIS)

    Shipra, R.; Kumar, Nitesh; Sundaresan, A.

    2013-01-01

    Nanocrystalline δ-NbN x samples have been synthesized by reacting NbCl 5 and urea at three different temperatures. A comparison of their structural, magnetic, transport and thermal properties is reported in the present study. The size of the particles and their agglomeration extent increase with increasing reaction temperature. The sample prepared at 900 °C showed the highest superconducting transition temperature (T c ) of 16.2 K with a transition width, ∼1.8 K, as obtained from the resistivity measurement on cold-pressed bars. Above T c , magnetization measurements revealed the presence of surface ferromagnetism which coexists with superconductivity below T c . Heat capacity measurements confirm superconductivity with strong electron–phonon coupling constant. The sample prepared at 800 °C shows a lower T c (10 K) while that prepared at 700 °C exhibit no superconductivity down to the lowest temperature (3 K) measured. - Highlights: ► Synthesis of δ-NbN nanoparticles by urea nitridation of NbCl 5 . ► Superconducting transition temperature (T c ) is 16.2 K. ► Superconductivity and surface ferromagnetism coexist in the nanoparticles. ► Effect of size and agglomeration on the physical properties of nanoparticles

  11. Yttrium ion implantation on the surface properties of magnesium

    International Nuclear Information System (INIS)

    Wang, X.M.; Zeng, X.Q.; Wu, G.S.; Yao, S.S.

    2006-01-01

    Owing to their excellent physical and mechanical properties, magnesium and its alloys are receiving more attention. However, their application has been limited to the high reactivity and the poor corrosion resistance. The aim of the study was to investigate the beneficial effects of ion-implanted yttrium using a MEVVA ion implanter on the surface properties of pure magnesium. Isothermal oxidation tests in pure O 2 at 673 and 773 K up to 90 min indicated that the oxidation resistance of magnesium had been significantly improved. Surface morphology of the oxide scale was analyzed using scanning electron microscope (SEM). Auger electron spectroscopy (AES) and X-ray diffraction (XRD) analyses indicated that the implanted layer was mainly composed of MgO and Y 2 O 3 , and the implanted layer with a duplex structure could decrease the inward diffusion of oxygen and reduce the outward diffusion of Mg 2+ , which led to improving the oxidation resistance of magnesium. Potentiodynamic polarization curves were used to evaluate the corrosion resistance of the implanted magnesium. The results show yttrium implantation could enhance the corrosion resistance of implanted magnesium compared with that of pure magnesium

  12. Properties and cleanability of new and traditional agricultural surface materials

    Directory of Open Access Journals (Sweden)

    J. MÄÄTTÄ

    2008-12-01

    Full Text Available The aim of the present study was to evaluate new and traditional surface materials for use in cattle barns. The evaluated concrete materials had different compositions and included different additives and coatings. Contact angle meter, optical profilometry and scanning electron microscopy SEM were used for characterization of surface properties. Radiochemical methods and a biochemical adenosine triphosphate ATP method were used to determine cleanability. A specific methodological aim was to examine the correlations between these determination methods. A statistically significant difference was observed between contact angles of non-coated concretes, coated concretes and joint materials. In general, coatings smoothened surfaces and the joint materials were the roughest surfaces, as illustrated by profilometry and SEM. On the basis of the radiochemical determination methods, coatings improved the cleanability of concrete. An epoxy joint material was cleaned efficiently from the oil model soil and from the labelled feed soil when compared to the two cement-based joint materials. According to the results of the biochemical ATP method the manure test soil was cleaned better from a concrete including inorganic sealant than from the other materials examined. The cleanability results of oil model soil used in the radiochemical method correlated with the results of the test feed soil used in the biochemical ATP method. Both determination methods of cleanability appeared to be suitable for examining the cleanability of surfaces soiled with agricultural soils. Only the radiochemical determination gives detailed quantitative results, but it can be used only in laboratory studies. The results of this laboratory study will be used for selecting materials for a pilot study in a cattle barn.;

  13. Coal resources availability in Botswana

    International Nuclear Information System (INIS)

    Modisi, M.P.

    1990-01-01

    This paper reports that Southern Africa, and Botswana in particular, is well-endowed with relatively large reserves of coal. The existence of coal in Botswana has been known since the end of the last century. Exploration activities by the Geological Survey and the private sector led to the discovery of major deposits and by the late 1960s reserves capable of supporting a mine at Morupule for the domestic market has been confirmed. The oil crises of 1973-74 and 1978-79 stimulated increased interest in coal exploration the world over and Botswana attracted several private sector companies looking for coal that could be traded on the international market. As a result vast resources and reserves of low to medium quality bituminous coal, suitable for the export market, were proved. Resources amounting to 21,680 million tonnes of in situ coal had been revealed by 1987. Reserves of possible economic exploitation are estimated at 10,180 million tonnes in two coal field areas, namely the Morupule Coal Field and the Mmamabula Coal Field. Since the collapse of oil prices and consequently coal prices in the mid-1980s, enthusiasm for coal exploration has plummeted and relatively little prospecting has taken place. The coal occurs within the Upper Carboniferous to Jurassic Karoo Supergroup which underlies some 60 percent of the country's land surface. The western part of the country is mantled by the Kalahari beds, a top layer of unconsolidated sands masking bedrock geology. Although coal seams have been intersected in boreholes in this western area, most exploration activity has taken place in the eastern part of the country where the Morupule and Mmamabula coal fields are located. It is in the east that most of the population is concentrated and infrastructure has been developed

  14. A summary of fish and wildlife information needs to surface mine coal in the United States. Part 2. The status of state surface mining regulations as of January 1980 and the fish and wildlife information needs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-01-01

    This is part 2 of a three part series to assist government agencies and private citizens in determining fish and wildlife information needs for new coal mining operations pursuant to the Surface Mining Control and Reclamation Act of 1977. This portion documents the status of individual state surface mining regulations as of January 1980 in those states having significant strippable reserves and/or active strip mining operations. It also provides documentation of fish and wildlife information needs identified in the state regulations of compliance to PL 95-87.

  15. Surface Estimation, Variable Selection, and the Nonparametric Oracle Property.

    Science.gov (United States)

    Storlie, Curtis B; Bondell, Howard D; Reich, Brian J; Zhang, Hao Helen

    2011-04-01

    Variable selection for multivariate nonparametric regression is an important, yet challenging, problem due, in part, to the infinite dimensionality of the function space. An ideal selection procedure should be automatic, stable, easy to use, and have desirable asymptotic properties. In particular, we define a selection procedure to be nonparametric oracle (np-oracle) if it consistently selects the correct subset of predictors and at the same time estimates the smooth surface at the optimal nonparametric rate, as the sample size goes to infinity. In this paper, we propose a model selection procedure for nonparametric models, and explore the conditions under which the new method enjoys the aforementioned properties. Developed in the framework of smoothing spline ANOVA, our estimator is obtained via solving a regularization problem with a novel adaptive penalty on the sum of functional component norms. Theoretical properties of the new estimator are established. Additionally, numerous simulated and real examples further demonstrate that the new approach substantially outperforms other existing methods in the finite sample setting.

  16. Surface properties, solubility and dissolution kinetics of bamboo phytoliths

    Science.gov (United States)

    Fraysse, Fabrice; Pokrovsky, Oleg S.; Schott, Jacques; Meunier, Jean-Dominique

    2006-04-01

    Although phytoliths, constituted mainly by micrometric opal, exhibit an important control on silicon cycle in superficial continental environments, their thermodynamic properties and reactivity in aqueous solution are still poorly known. In this work, we determined the solubility and dissolution rates of bamboo phytoliths collected in the Réunion Island and characterized their surface properties via electrophoretic measurements and potentiometric titrations in a wide range of pH. The solubility product of "soil" phytoliths ( pKsp0=2.74 at 25 °C) is equal to that of vitreous silica and is 17 times higher than that of quartz. Similarly, the enthalpy of phytoliths dissolution reaction (ΔHr25-80°C=10.85kJ/mol) is close to that of amorphous silica but is significantly lower than the enthalpy of quartz dissolution. Electrophoretic measurements yield isoelectric point pH IEP = 1.2 ± 0.1 and 2.5 ± 0.2 for "soil" (native) and "heated" (450 °C heating to remove organic matter) phytoliths, respectively. Surface acid-base titrations allowed generation of a 2-p K surface complexation model. Phytoliths dissolution rates, measured in mixed-flow reactors at far from equilibrium conditions at 2 ⩽ pH ⩽ 12, were found to be intermediate between those of quartz and vitreous silica. The dissolution rate dependence on pH was modeled within the concept of surface coordination theory using the equation: R=k1·{>SiOH2+}n+k2·{>SiOH0}+k3·{>SiO-}m, where {> i} stands for the concentration of the surface species present at the SiO 2-H 2O interface, ki are the rate constants of the three parallel reactions and n and m represent the order of the proton- and hydroxy-promoted reactions, respectively. It follows from the results of this study that phytoliths dissolution rates exhibit a minimum at pH ˜ 3. This can explain their good preservation in the acidic soil horizons of Réunion Island. In terms of silicon biogeochemical cycle, phytoliths represent a large buffering reservoir

  17. Australian coal

    Energy Technology Data Exchange (ETDEWEB)

    1985-11-01

    Total export shipments of coal in Australia in the year ending June 30 1985 reached a record of 83.8 Mt. The export trade is expected to bring in an income of 4 billion Australian dollars in the current year making coal Australia's biggest revenue-earning export commodity. This article presents a brief overview of the Australian coal industry with production and export statistics and information on major open pit and underground mines.

  18. Physico-chemical and optical properties of combustion-generated particles from coal-fired power plant, automobile and ship engine and charcoal kiln.

    Science.gov (United States)

    Kim, Hwajin

    2015-04-01

    Similarities and differences in physico-chemical and optical properties of combustion generated particles from various sources were investigated. Coal-fired power plant, charcoal kiln, automobile and ship engine were major sources, representing combustions of coal, biomass and two different types of diesel, respectively. Scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and energy-dispersive X-ray spectroscopy (EDX) equipped with both SEM and HRTEM were used for physico-chemical analysis. Light absorbing properties were assessed using a spectrometer equipped with an integrating sphere. Particles generated from different combustion sources and conditions demonstrate great variability in their morphology, structure and composition. From coal-fired power plant, both fly ash and flue gas were mostly composed of heterogeneously mixed mineral ash spheres, suggesting that the complete combustion was occurred releasing carbonaceous species out at high temperature (1200-1300 °C). Both automobile and ship exhausts from diesel combustions show typical features of soot: concentric circles comprised of closely-packed graphene layers. However, heavy fuel oil (HFO) combusted particles from ship exhaust demonstrate more complex compositions containing different morphology of particles other than soot, e.g., spherical shape of char particles composed of minerals and carbon. Even for the soot aggregates, particles from HFO burning have different chemical compositions; carbon is dominated but Ca (29.8%), S (28.7%), Na(1%), and Mg(1%) are contained, respectively which were not found from particles of automobile emission. This indicates that chemical compositions and burning conditions are significant to determine the fate of particles. Finally, from biomass burning, amorphous and droplet-like carbonaceous particles with no crystallite structure are observed and they are generally formed by the condensation of low volatile species at low

  19. Methane emissions from coal mining

    International Nuclear Information System (INIS)

    Boyer, C.M.; Kelafant, J.R.; Kuuskraa, V.A.; Manger, K.C.; Kruger, D.

    1990-09-01

    The report estimates global methane emissions from coal mining on a country specific basis, evaluates the technologies available to degasify coal seams and assesses the economics of recovering methane liberated during mining. 33 to 64 million tonnes were liberated in 1987 from coal mining, 75 per cent of which came from China, the USSR, Poland and the USA. Methane emissions from coal mining are likely to increase. Emission levels vary between surface and underground mines. The methane currently removed from underground mines for safety reasons could be used in a number of ways, which may be economically attractive. 55 refs., 19 figs., 24 tabs

  20. Coal - 96

    International Nuclear Information System (INIS)

    Sparre, C.

    1996-09-01

    The report deals mainly with coal consumption, but also gives some information about technology, environmental aspects and markets. Data have been collected by questionnaires or via telephone. The use of steam coal for heating was 0.8 Mtons (down 20% from 1994). Cogeneration plants were the main users. Taxes and environmental reasons cause a reduction of the coal use that will probably continue the next years. Use of steam coal in industry has been constant at a level of 0.7 Mtons. The import of metallurgical coal rests constant at a level of 1.6 Mtons. 1.2 Mtons of coke was produced, and 0.3 Mtons imported. The PFBC-plant at Vaertan, Stockholm used 0.13 Mtons of coal, while some coal fired power plants have been converted to peat and wood fuels. The average price of steam coal imported to Sweden in 1995 was 333 SEK/ton, 6% higher than in 1994. The contract prices for delivery 1996 are about the same as at the end of 1995. All cogeneration plants have some sort of SO 2 removal system, mostly wet-dry. The largest plant, at Vaesteraas, has recently invested in a SCR system for NO x removal. Most other plants are using low NO x burners or SNCR systems, based on ammonia or urea, which reduce the emissions 50 - 70%. Some statistic about the world coal market is also given in the report

  1. Venezuelan coal

    International Nuclear Information System (INIS)

    Vazquez, L.U.

    1991-01-01

    The existence of coal deposits in Venezuela has been known since the early nineteenth century, when the Naricual Mines were discovered in the State of Anzoategui Eastern Venezuela. Through the years the Venezuelan coal business had its ups and downs, but it was not until 1988 that we could properly say that our coal began to play a role in the international market. This paper reports that it is only now, in the nineties, that Venezuelan coal projects have come under a planning, promotional and developmental policy preparing the ground for the great projects Venezuela will have in the not-too-distant future

  2. Micromechanical and surface adhesive properties of single saccharomyces cerevisiae cells

    Science.gov (United States)

    Farzi, Bahman; Cetinkaya, Cetin

    2017-09-01

    The adhesion and mechanical properties of a biological cell (e.g. cell membrane elasticity and adhesiveness) are often strong indicators for the state of its health. Many existing techniques for determining mechanical properties of cells require direct physical contact with a single cell or a group of cells. Physical contact with the cell can trigger complex mechanotransduction mechanisms, leading to cellular responses, and consequently interfering with measurement accuracy. In the current work, based on ultrasonic excitation and interferometric (optical) motion detection, a non-contact method for characterizing the adhesion and mechanical properties of single cells is presented. It is experimentally demonstrated that the rocking (rigid body) motion and internal vibrational resonance frequencies of a single saccharomyces cerevisiae (SC) (baker’s yeast) cell can be acquired with the current approach, and the Young’s modulus and surface tension of the cell membrane as well as surface adhesion energy can be extracted from the values of these acquired resonance frequencies. The detected resonance frequency ranges for single SC cells include a rocking (rigid body) frequency of 330  ±  70 kHz and two breathing resonance frequencies of 1.53  ±  0.12 and 2.02  ±  0.31 MHz. Based on these values, the average work-of-adhesion of SC cells on a silicon substrate in aqueous medium is extracted, for the first time, as WASC-Si=16.2+/- 3.8 mJ {{m}-2} . Similarly, the surface tension and the Young’s modulus of the SC cell wall are predicted as {{σ }SC}=0.16+/- 0.02 N {{m}-1} and {{E}SC}= 9.20  ±  2.80 MPa, respectively. These results are compared to those reported in the literature by utilizing various methods, and good agreements are found. The current approach eliminates the measurement inaccuracies associated with the physical contact. Exciting and detecting cell dynamics at micro-second time-scales is significantly faster than the

  3. Structure and optical properties of water covered Cu(110) surfaces

    International Nuclear Information System (INIS)

    Baghbanpourasl, A.

    2014-01-01

    In this thesis structural and optical properties of the water covered Cu(110) surface is studied using density functional theory within independent particle approximation. Several stable adsorption structures are studied such as water clusters (monomer, dimer, trimer, tetramer and pentamer), different hexagonal monolayers, partially dissociated water monolayers and three different types of chains among them a chain that consists of pentagon rings. For a copper surface in contact with water vapor, the energetically stable H 2 O/OH adsorbed structures are compared thermodynamically using adsorption free energy (change of free energy due to adsorption). Several phase diagrams with respect to temperature and pressure are calculated. It is found that among the large number of energetically stable structures (i.e. structures with positive adsorption energy ) only limited number of them are thermodynamically stable. These thermodynamically stable structures are the class of almost energetically degenerate hexagonal overlayers, one type of partially dissociated water structure that contains Bjerrum defect in the hydrogen bond network and pentagon chain. Since hydrogen atoms are light weight their vibrational effects can be considerable. Zero point vibration decreases the adsorption energy up to 0.1 eV and free energy of adsorbed molecules arising from vibrational degree of freedom can go up to -0.2 eV per adsorbed molecule at 500 Kelvin. However zero point energy and vibrational free energy of adsorbed molecules do not alter relative stability of the adsorbed structures. To account for the long range van der Waals interactions, a semi-empirical scheme is applied. Reflectance Anisotropy Spectroscopy (RAS) is a fast and non destructive optical method that can be used to prob the surface in different conditions such as vacuum and electro-chemical environment. Elasto-optic coeficients of bulk are calculated from first principles and the change of the RA spectrum of the bare Cu

  4. Effective pretreatment of coal for briquetting

    Energy Technology Data Exchange (ETDEWEB)

    Sunami, Y; Nishioka, K; Sugimoto, Y

    1980-01-01

    The pretreatment of coal for briquetting is considered in an attempt to improve the quality of the briquets produced. Crushing of coal to obtain a size distribution suitable for close packing was found to be effective in improving coking properties while drying of coal was found to be effective in increasing briquet density. (In Japanese)

  5. Cleaning and dewatering fine coal

    Science.gov (United States)

    Yoon, Roe-Hoan; Eraydin, Mert K.; Freeland, Chad

    2017-10-17

    Fine coal is cleaned of its mineral matter impurities and dewatered by mixing the aqueous slurry containing both with a hydrophobic liquid, subjecting the mixture to a phase separation. The resulting hydrophobic liquid phase contains coal particles free of surface moisture and droplets of water stabilized by coal particles, while the aqueous phase contains the mineral matter. By separating the entrained water droplets from the coal particles mechanically, a clean coal product of substantially reduced mineral matter and moisture contents is obtained. The spent hydrophobic liquid is separated from the clean coal product and recycled. The process can also be used to separate one type of hydrophilic particles from another by selectively hydrophobizing one.

  6. Improvement of carbon fibre surface properties using electron beam irradiation

    International Nuclear Information System (INIS)

    Eddy Segura Pino; Luci Diva Brocardo Machado; Claudia Giovedi

    2006-01-01

    Carbon fiber-reinforced advance composites have been used for structural applications, mainly due to their mechanical properties, and additional features such as high strength-to-weight ratio, stiffness-to-weight ratio, corrosion resistance and wear properties. The main factor for a good mechanical performance of carbon fiber-reinforced composite is the interfacial interaction between the components that are fiber and polymeric matrix. The greatest challenge is to improve adhesion between components having elasticity modulus which differ by orders of magnitude and furthermore they are immiscible in each other. Another important factor is the sizing material on the carbon fiber, which protects the carbon fiber filaments and must be compatible with the matrix material in order to improve the adhesion process. The interaction of ionizing radiation from electron beam can induce in the irradiated material the formation of very active centers and free radicals. Further evolution of these active species can significantly modify structure and properties not only in the irradiated polymeric matrix but also on the fiber surface. So that, fiber and matrix play an important role in the production of chemical bonds, which promote better adhesion between both materials improving the composite mechanical performance. The aim of this work was to improve the surface properties of the carbon fiber surface using ionizing radiation from an electron beam in order to obtain improvement of the adhesion properties in the resulted composite. Commercial carbon fiber roving of high tensile strength with 12 000 filaments named 12 k, and sizing material of epoxy resin modified by ester groups was studied. EB irradiation has been carried out at the Institute for Nuclear and Energy Research (IPEN) facilities using a 1.5 MeV 37.5 kW Dynamitron electron accelerator model JOB-188. Rovings of carbon fibers with 1.78 g cm -3 density and 0.13 mm thickness were irradiated with 0.555 MeV, 6.43 mA and

  7. Washability characteristics of residual coals obtained from solvent extraction: studies towards developing cleaner coal technology

    Energy Technology Data Exchange (ETDEWEB)

    Giri, C.C.; Sharma, D.K. [Indian Institute of Technology, New Delhi (India). Centre for Energy Studies

    2004-07-01

    The washability characteristics of original Indian coals and solvent-extracted residual coals were studied by the float and sink technique. The following conclusions were drawn on the basis of the present study. Anthracene oil-extracted residual coals have lower percentage of reactions in the specific gravity range of 1.4 to 1.6 than the original coals, which indicates that the mineral matter is disassociated from the organic mass, and the anthracene oil-extracted residual coal is more suitable for washing than the original coal. The floatability behaviour of coal increases during NMP (N-methyl-2-pyrrolidone) extraction. This indicates that coal changes its washability character during NMP extractions. As during NMP extraction the surface area of coal increases by creating fissures in the matrix, the chemical leaching technique would be more suitable to remove the mineral matter in the residual coals. 12 refs., 3 figs., 2 tabs.

  8. Computer-aided planning of brown coal seam mining in regard to coal quality

    Energy Technology Data Exchange (ETDEWEB)

    Ciesielski, R.; Lehmann, A.; Rabe, H.; Richter, S.

    1988-09-01

    Discusses features of the geologic SORVER software developed at the Freiberg Fuel Institute, GDR. The program processes geologic data from exploratory wells, petrographic characteristics of a coal seam model, technological mining parameters and coal quality requirements of consumers. Brown coal reserves of coking coal, gasification coal, briquetting coal and steam coal are calculated. Vertical seam profiles and maps of seam horizon isolines can be plotted using the program. Coal quality reserves along the surface of mine benches, mining block widths and lengths for excavators, maximum possible production of individual coal qualities by selective mining, and coal quality losses due to mining procedures are determined. The program is regarded as a means of utilizing deposit reserves more efficiently. 5 refs.

  9. Intermolecular potential energy surface and thermophysical properties of propane.

    Science.gov (United States)

    Hellmann, Robert

    2017-03-21

    A six-dimensional potential energy surface (PES) for the interaction of two rigid propane molecules was determined from supermolecular ab initio calculations up to the coupled cluster with single, double, and perturbative triple excitations level of theory for 9452 configurations. An analytical site-site potential function with 14 sites per molecule was fitted to the calculated interaction energies. To validate the analytical PES, the second virial coefficient and the dilute gas shear viscosity and thermal conductivity of propane were computed. The dispersion part of the potential function was slightly adjusted such that quantitative agreement with the most accurate experimental data for the second virial coefficient at room temperature was achieved. The adjusted PES yields values for the three properties that are in very good agreement with the best experimental data at all temperatures.

  10. Integrated coal preparation

    International Nuclear Information System (INIS)

    Buchanan, D.J.; Jones, T.F.

    1992-01-01

    Perceptions of quality have changed over the years. The attributes of a certain coal (its rank, slagging propensity, ash content etc) are traditionally referred to as its quality. However, the subject of this paper is quality in a much wider sense: quality as fitness for purpose: and all that such a wide definition entails. British Standard BS 5750 (ISO 9000) Quality Systems defines a systems approach to quality, and includes both the supplier of raw materials and the final customer within this boundary. Coal preparation starts at the production face. The greater the proportion of dirt in run-of-mine product the greater the challenge in satisfying the customer's needs. Significant advances have been made in minimizing mined dirt. For example, the sue of vertical steering on longwall faces improves productivity and quality. Unfortunately modern mining methods produce large quantities of fines, despite efforts to reduce them at the point of production and during transportation to the surface. Coal preparation also produces further fines. It has been estimated that fine coal costs 2.5 times as much to clean as large coal, and the costs of handing wet fine coal product will inflate this estimate. Handling considerations rightly concern our customers and are part of the wider meaning of quality. In this paper the authors address some novel solutions to the challenge posed by fines

  11. Substrate texture properties induce triatomine probing on bitten warm surfaces

    Directory of Open Access Journals (Sweden)

    Lorenzo Marcelo G

    2011-06-01

    Full Text Available Abstract Background In this work we initially evaluated whether the biting process of Rhodnius prolixus relies on the detection of mechanical properties of the substrate. A linear thermal source was used to simulate the presence of a blood vessel under the skin of a host. This apparatus consisted of an aluminium plate and a nickel-chrome wire, both thermostatized and presented at 33 and 36°C, respectively. To evaluate whether mechanical properties of the substrate affect the biting behaviour of bugs, this apparatus was covered by a latex membrane. Additionally, we evaluated whether the expression of probing depends on the integration of bilateral thermal inputs from the antennae. Results The presence of a latex cover on a thermal source induced a change in the biting pattern shown by bugs. In fact, with latex covered sources it was possible to observe long bites that were never performed in response to warm metal surfaces. The total number of bites was higher in intact versus unilaterally antennectomized insects. These bites were significantly longer in intact than in unilaterally antennectomized insects. Conclusions Our results suggest that substrate recognition by simultaneous input through thermal and mechanical modalities is required for triggering maxillary probing activity.

  12. Research status and future trends on surface pre-grouting technology in reforming wall rock of vertical shafts in coal mines in China

    Science.gov (United States)

    Wang, Hua

    2018-02-01

    In the mine construction, the surface pre-grouting technology is an important method to prevent water blast in excavation process of vertical shaft when the shaft must pass through the thick, water-rich and high water-pressure bedrock aquifer. It has been nearly 60 years since the technology was used to reform wall rock of vertical shaft in coal mine in China for the first time, and the existing technology can basically meet the needs of constructing 1000m deep vertical shaft. Firstly, the article introduces that in view of Magg’s spherical seepage theory and Karol’s spherical seepage theory, Chinese scholars found that the diffusion of grout from borehole into the surrounding strata in horizontal direction is irregular through a lot of research and engineering practice of using the surface pre-grouting technology to reform wall rock of vertical shafts, and put forward the selecting principles of grout’s effective diffusion radius in one grouting engineering; Secondly, according to the shape of the grouting boreholes, surface pre-grouting technology of vertical shaft is divided into two stages: vertical borehole stage and S-type borehole stage. Thirdly, the development status of grouting materials and grouting equipment for the technology is introduced. Fourthly, grouting mode, stage height and pressure of the technology are introduced. Finally, it points out that with the increasing depth of coal mining in China, the technology of reforming wall rock of 1000~2000m deep vertical shafts will face many problems, such as grouting theory, grouting equipment, grouting finishing standard, testing and evaluation of grouting effect, and so on. And it put forward a preliminary approach to solving these problems. This paper points out future research directions of the surface pre-grouting technology in China.

  13. Atomistic simulations of bulk, surface and interfacial polymer properties

    Science.gov (United States)

    Natarajan, Upendra

    In chapter I, quasi-static molecular mechanics based simulations are used to estimate the activation energy of phenoxy rings flips in the amorphous region of a semicrystalline polyimide. Intra and intermolecular contributions to the flip activation energy, the torsional cooperativity accompanying the flip, and the effect of the flip on the motion in the glassy bulk state, are looked at. Also, comparison of the weighted mean activation energy is made with experimental data from solid state NMR measurements; the simulated value being 17.5 kcal/mol., while the experimental value was observed to be 10.5 kcal/mol. Chapter II deals with construction of random copolymer thin films of styrene-butadiene (SB) and styrene-butadiene-acrylonitrile (SBA). The structure and properties of the free surfaces presented by these thin films are analysed by, the atom mass density profiles, backbone bond orientation function, and the spatial distribution of acrylonitrile groups and styrene rings. The surface energies of SB and SBA are calculated using an atomistic equation and are compared with experimental data in the literature. In chapter III, simulations of polymer-polymer interfaces between like and unlike polymers, specifically cis-polybutadiene (PBD) and atatic polypropylene (PP), are presented. The structure of an incompatible polymer-polymer interface, and the estimation of the thermodynamic work of adhesion and interfacial energy between different incompatible polymers, form the focus here. The work of adhesion is calculated using an atomistic equation and is further used in a macroscopic equation to estimate the interfacial energy. The interfacial energy is compared with typical values for other immiscible systems in the literature. The interfacial energy compared very well with interfacial energy values for a few other immiscible hydrocarbon pairs. In chapter IV, the study proceeds to look at the interactions between nonpolar and polar small molecules with SB and SBA thin

  14. Mapping surface properties of sinusoidal roughness standards by TPM

    International Nuclear Information System (INIS)

    Liu, X; Rubert, P

    2005-01-01

    We report our investigation on the surface properties of sinusoidal roughness standards made from pure electroformed nickel. Two specimens having a sinusoidal profile with nominal R a of 0.36 μm and a peak spacing of 25 μm are chosen for this investigation. One specimen is further treated with a hard protective coating of nickel-boron. The surface topography, friction, hardness and Young's modulus of the specimens were measured by a novel instrument, the multi-function Tribological Probe Microscope (TPM). The results show that hardness of these two specimens is 14.1 GPa for uncoated specimen and 25.7 GPa for the coated one, while the Young's modulus is 188 GPa and 225 GPa, respectively. The ramping force was set to 3mN for both the specimens and the effect of the tip penetration was investigated by comparing the topography measurements before and after hardness mapping. It has been found out that there is no significant change in the averaged profiles over the scanned area, which indicates the topography distortion seen in the multi-function mapping, is recoverable. Cross correlation between topography and its corresponding hardness/Young's modulus has been carried out and the result will be discussed in the paper

  15. Surface molecular aggregation structure and surface physicochemical properties of poly(fluoroalkyl acrylate) thin films

    International Nuclear Information System (INIS)

    Honda, K; Yamaguchi, H; Takahara, A; Kobayashi, M; Morita, M

    2008-01-01

    Effect of side chain length on the molecular aggregation states and surface properties of poly(fluoroalkyl acrylate)s [PFA-C y , where y is fluoromethylene number in R f group] thin films were systematically investigated. Spin-coated PFA-C y thin films were characterized by static and dynamic contact angle measurements, X-ray photoelectron spectroscopy (XPS), and grazing- incidence X-ray diffraction (GIXD). The receding contact angles showed small values for PFA-C y with short side chain (y≤6) and increased above y≥8. GIXD revealed that fluoroalkyl side chain of PFA-C y with y≥8 was crystallized and formed ordered structures at the surface region as well as bulk one. These results suggest that water repellent mechanism of PFA-C y can be attributed to the presence of highly ordered fluoroalkyl side chains at the outermost surfaces. The results of XPS in the dry and hydrated states and contact angle measurement in water support the mechanism of lowering contact angle for water by exposure of carbonyl group to the water interface through reorientation of short fluoroalkyl chains. The surface nanotextured PFA-C 8 through imprinting of anodic aluminum oxide mold showed extremely high hydrophobicity as well as high oleophobicity

  16. Coal summit II

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    Various papers were presented on world coal trade. Papers include: Poland as a producer and exporter of coal; the dynamics of world coal trade; Cerrejon coal production perspectives; present state of the Australian coal industry; present state of the EC coal market and future prospects; prospects of US coal exports to Europe; forecast of Italian coal supply and demand through 1990; statistics from coal transportation outlook; status of world coal ports.

  17. Fluidised bed gasification of low grade South African coals

    CSIR Research Space (South Africa)

    North, BC

    2006-09-01

    Full Text Available gasifiers. Fluidised bed Entrained flow Coal particle size 0.5 mm – 5 mm 0 – 0.5 mm Coal moisture Dry Dry/slurry Coal type Non-caking coals Any coal Ash in coal < 60% < 30% Gasification agents Air/steam/oxygen Steam/oxygen Gasification... properties important for fluidised bed gasification are: square4 Coal reactivity in atmospheres of CO2 and H2O square4 Caking index and free swelling index (FSI) square4 Ash fusion temperature (AFT) 5.1 Coal reactivity The gasifcation reactions (1...

  18. Adaptive Surface Modeling of Soil Properties in Complex Landforms

    Directory of Open Access Journals (Sweden)

    Wei Liu

    2017-06-01

    Full Text Available Abstract: Spatial discontinuity often causes poor accuracy when a single model is used for the surface modeling of soil properties in complex geomorphic areas. Here we present a method for adaptive surface modeling of combined secondary variables to improve prediction accuracy during the interpolation of soil properties (ASM-SP. Using various secondary variables and multiple base interpolation models, ASM-SP was used to interpolate soil K+ in a typical complex geomorphic area (Qinghai Lake Basin, China. Five methods, including inverse distance weighting (IDW, ordinary kriging (OK, and OK combined with different secondary variables (e.g., OK-Landuse, OK-Geology, and OK-Soil, were used to validate the proposed method. The mean error (ME, mean absolute error (MAE, root mean square error (RMSE, mean relative error (MRE, and accuracy (AC were used as evaluation indicators. Results showed that: (1 The OK interpolation result is spatially smooth and has a weak bull's-eye effect, and the IDW has a stronger ‘bull’s-eye’ effect, relatively. They both have obvious deficiencies in depicting spatial variability of soil K+. (2 The methods incorporating combinations of different secondary variables (e.g., ASM-SP, OK-Landuse, OK-Geology, and OK-Soil were associated with lower estimation bias. Compared with IDW, OK, OK-Landuse, OK-Geology, and OK-Soil, the accuracy of ASM-SP increased by 13.63%, 10.85%, 9.98%, 8.32%, and 7.66%, respectively. Furthermore, ASM-SP was more stable, with lower MEs, MAEs, RMSEs, and MREs. (3 ASM-SP presents more details than others in the abrupt boundary, which can render the result consistent with the true secondary variables. In conclusion, ASM-SP can not only consider the nonlinear relationship between secondary variables and soil properties, but can also adaptively combine the advantages of multiple models, which contributes to making the spatial interpolation of soil K+ more reasonable.

  19. Upgrading of brown coal by slurry-dewatering; Kattan no yuchu dassui ni yoru clean kotai nenryo no seizo

    Energy Technology Data Exchange (ETDEWEB)

    Okuma, O.; Shimizu, T.; Inoue, T.; Shigehisa, T.; Deguchi, T.; Katsushima, S. [Kobe Steel, Ltd., Kobe (Japan)

    1996-10-28

    This paper describes an outline of solid fuel production process from brown coal and the investigation results of its elemental techniques. Dried coal is produced by this process which consists of a dewatering of crushed brown coal in oil-based solvent, a solid and liquid separation of slurry, and a remained oil recovery by heating. This process is characterized by the higher thermal efficiency compared with usual drying and the restraint of spontaneous combustion of product coal. It was revealed that solid fuel with low moisture, low ash, low sulfur, and suppressed spontaneous combustion property can be produced from Australian brown coal through this process. From the comparison between kerosene and fuel oil A, it was confirmed that the oil content during dewatering was smaller and the oil recovery by heating was easier by using a solvent with lower boiling point. It was also confirmed that the spontaneous combustion property can be suppressed using small amount of asphalt by solving asphalt in the solvent and adsorbing asphalt on the surface of brown coal. From these results, low rank coals including brown coal, which are difficult to use, are expected to be used as clean coal with low ash and low sulfur through this process. 2 refs., 7 figs., 2 tabs.

  20. Map showing selected surface-water data for the Alton-Kolob coal-fields area, Utah

    Science.gov (United States)

    Price, Don

    1982-01-01

    This is one of a series of maps that describe the geology and related natural resources of the Alton-Kolob coal-fields area, Utah. Streamflow records used to compile the map and the following table were collected by the U.S. Geological Survey in cooperation with the Utah Department of Natural Resources, Division of Water Rights, and the Utah Department of Transportation. The principal runoff-producing areas were delineated form a work map (scale 1:250,000) compiled to estimate water yields in Utah (Bagley and others, 1964).

  1. High-calcium coal combustion by-products: Engineering properties, ettringite formation, and potential application in solidification and stabilization of selenium and boron

    Energy Technology Data Exchange (ETDEWEB)

    Solem-Tishmack, J.K.; McCarthy, G.J. [North Dakota State Univ., Fargo, ND (United States). Dept. of Chemistry; Docktor, B.; Eylands, K.E.; Thompson, J.S.; Hassett, D.J. [Univ. of North Dakota, Grand Forks, ND (United States). Energy and Environmental Research Center

    1995-04-01

    Four high-calcium coal combustion by-products (two pulverized coal fly ashes (PCFA), a flue gas desulfurization (FGD) residue, and an atmospheric fluidized bed combustion (AFBC) fly ash), were tested for engineering properties and ability to immobilize boron and selenium. These data are needed to explore high-volume utilization in engineered structure or in solidification/stabilization (S/S) technology. Strengths of cured pastes (91 days), varied from as much as 27 MPa (3,900 psi) for one of the PCFA specimens to 4.6 MPa (670 psi) for the FGD specimen. All of the coal by-product pastes developed more than the 0.34 MPa (50 psi) required for S/S applications. Ettringite formation is important to engineering properties and S/S mechanisms. XRD on plain specimens cured for 91 days indicated that the two PCFA pastes formed 5--6% ettringite, the FGD paste formed 22%, and the AFBC paste formed 32%. The hydrating PCFA pastes showed little expansion, the FGD paste contracted slightly, and the AFBC paste expanded by 2.9% over 91 days. Se and B were spiked into the mixing water as sodium selenite, selenate and borate, and for most pastes this had little effect on strength, workability, and expansion. Leaching of ground specimens (cured for 91 days) showed a generally positive correlation between the amount of ettringite formed and resistance to Se and B leaching. Se spiked as selenate was more readily leached than Se spiked as selenite. B showed a high level of fixation.

  2. Coal fires in Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Whitehouse, Alfred E.; Mulyana, Asep A.S. [Office of Surface Mining/Ministry of Energy and Mineral Resources Coal Fire Project, Ministry of Energy and Mineral Resources, Agency for Training and Education, Jl. Gatot Subroto, Kav. 49, Jakarta 12950 (Indonesia)

    2004-07-12

    Indonesia's fire and haze problem is increasingly being ascribed to large-scale forest conversion and land clearing activities making way for pulpwood, rubber and oil palm plantations. Fire is the cheapest tool available to small holders and plantation owners to reduce vegetation cover and prepare and fertilize extremely poor soils. Fires that escaped from agricultural burns have ravaged East Kalimantan forests on the island of Borneo during extreme drought periods in 1982-1983, 1987, 1991, 1994 and 1997-1998. Estimates based on satellite data and ground observations are that more than five million hectares were burned in East Kalimantan during the 1997/1998 dry season. Not only were the economic losses and ecological damage from these surface fires enormous, they ignited coal seams exposed at the ground surface along their outcrops.Coal fires now threaten Indonesia's shrinking ecological resources in Kutai National Park and Sungai Wain Nature Reserve. Sungai Wain has one of the last areas of unburned primary rainforest in the Balikpapan-Samarinda area with an extremely rich biodiversity. Although fires in 1997/1998 damaged nearly 50% of this Reserve and ignited 76 coal fires, it remains the most valuable water catchment area in the region and it has been used as a reintroduction site for the endangered orangutan. The Office of Surface Mining provided Indonesia with the capability to take quick action on coal fires that presented threats to public health and safety, infrastructure or the environment. The US Department of State's Southeast Asia Environmental Protection Initiative through the US Agency for International Development funded the project. Technical assistance and training transferred skills in coal fire management through the Ministry of Energy and Mineral Resource's Training Agency to the regional offices; giving the regions the long-term capability to manage coal fires. Funding was also included to extinguish coal fires as

  3. Rational use of coal from the Kansk-Achinsk basin

    Energy Technology Data Exchange (ETDEWEB)

    Andreeva, I.A.; Antonova, L.I.; Khapaeva, O.K.

    1983-02-01

    Brown coal from the Kansk-Achinsk basin will be used as fuel in power plants as well as raw material for production of coke and smokeless fuel. Production of semicoke should amount to 9 Mt/year, 4 Mt of which will be smokeless fuel. A method for coking brown coal from the Kansk-Achinsk basin developed by the MGI Institute is described: semicoke mixed with coal tar used as a binder and polymers (from 2 to 4%), playing the role of a modifier, is carbonized at 850 to 900 C. Briquets produced from brown coal semicoke are characterized by a high carbon content up to 94.7%, emission of volatile matter down to 9.0%, ash content of 8.8% and good mechanical properties. A method for production of coke for removal of sulfurous anhydride from coal power plant emission is described: semicoke is granulated using the heavy fraction of coal tar formed during semicoking, granules are carbonized and activated at a temperature of 900 C. Volume of mesopores and micropores in coke amounts to 0.4 cm/sup 3//g and the specific surface is 28 to 600 m/sup 2//g (with a combustion loss of of 20 to 24 %). This sorbent is also used as carrier for catalysts in metallurgy and for collecting and recovering solvents from industrial gases.

  4. Anisotropic surface chemistry properties and adsorption behavior of silicate mineral crystals.

    Science.gov (United States)

    Xu, Longhua; Tian, Jia; Wu, Houqin; Fang, Shuai; Lu, Zhongyuan; Ma, Caifeng; Sun, Wei; Hu, Yuehua

    2018-03-07

    Anisotropic surface properties of minerals play an important role in a variety of fields. With a focus on the two most intensively investigated silicate minerals (i.e., phyllosilicate minerals and pegmatite aluminosilicate minerals), this review highlights the research on their anisotropic surface properties based on their crystal structures. Four surface features comprise the anisotropic surface chemistry of minerals: broken bonds, energy, wettability, and charge. Analysis of surface broken bond and energy anisotropy helps to explain the cleavage and growth properties of mineral crystals, and understanding surface wettability and charge anisotropy is critical to the analysis of minerals' solution behavior, such as their flotation performance and rheological properties. In a specific reaction, the anisotropic surface properties of minerals are reflected in the adsorption strengths of reagents on different mineral surfaces. Combined with the knowledge of mineral crushing and grinding, a thorough understanding of the anisotropic surface chemistry properties and the anisotropic adsorption behavior of minerals will lead to the development of effective relational models comprising their crystal structure, surface chemistry properties, and targeted reagent adsorption. Overall, such a comprehensive approach is expected to firmly establish the connection between selective cleavage of mineral crystals for desired surfaces and designing novel reagents selectively adsorbed on the mineral surfaces. As tools to characterize the anisotropic surface chemistry properties of minerals, DLVO theory, atomic force microscopy (AFM), and molecular dynamics (MD) simulations are also reviewed. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. International Coal Report's coal year 1991

    Energy Technology Data Exchange (ETDEWEB)

    McCloskey, G [ed.

    1991-05-31

    Following introductory articles on factors affecting trade in coal and developments in the freight market, tables are given for coal exports and coal imports for major countries worldwide for 1989 and 1990. Figures are also included for coal consumption in Canada and the Eastern bloc,, power station consumption in Japan, coal supply and demand in the UK, electric utility coal consumption and stocks in the USA, coal production in Australia, Canada and USA by state, and world hard coal production. A final section gives electricity production and hard coal deliveries in the EEC, sales of imported and local coal and world production of pig iron and steel.

  6. Developing densification technology to facilitate briquetting of coal fines

    Energy Technology Data Exchange (ETDEWEB)

    Shi, R. [Ministry of Metallurgy (China). Anshan Thermal Energy Research Institute

    1997-01-01

    This paper introduces the densification technology in coal processing and the research of increasing the caking power of coal and its application. By exploiting the inherent caking property of coal, it is hoped to advance the briquetting technology so that coal fines is converted into high quality coke or briquette. This will produce very good social, economical and environmental benefit. 3 figs., 5 tabs.

  7. Development of a phenomenological model for coal slurry atomization

    Energy Technology Data Exchange (ETDEWEB)

    Dooher, J.P. [Adelphi Univ., Garden City, NY (United States)

    1995-11-01

    Highly concentrated suspensions of coal particles in water or alternate fluids appear to have a wide range of applications for energy production. For enhanced implementation of coal slurry fuel technology, an understanding of coal slurry atomization as a function coal and slurry properties for specific mechanical configurations of nozzle atomizers should be developed.

  8. In situ influence of coal ash dump on the quality of neighboring surface and ground waters by applying correlation statistic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jasna M. Djinovic; Aleksandar R. Popovic [University of Belgrade, Belgrade (Serbia and Montenegro). Center of Chemistry, Institute of Chemistry, Technology and Metallurgy

    2007-01-15

    The aim of this study was to establish the real in situ influence of coal ash and slag transport and storage on the quality of neighboring surface and ground waters by applying correlation statistic analysis. It was found that the waste waters from the coal ash dump do not have any influence on the quality of the Danube river water. The Danube and the waste waters, however, influence the quality of the ground waters of the Petka spring. Changes in the concentrations of elements in the Danube or in the waste waters can have immediate or delayed impact on the quality of the spring waters. The immediate impact has calcium, magnesium, zinc, copper, vanadium, cobalt from Danube; magnesium, vanadium from overflow and drainage waters; copper from drainage water. And the delayed impact has calcium, magnesium, vanadium and silicon from the Danube waters, cobalt from drainage waters, chromium and silicon from overflow waters and magnesium and vanadium from both overflow and drainage waters. 20 refs., 2 figs., 4 tabs.

  9. Thermal characteristics and surface morphology of char during co-pyrolysis of low-rank coal blended with microalgal biomass: Effects of Nannochloropsis and Chlorella.

    Science.gov (United States)

    Wu, Zhiqiang; Yang, Wangcai; Yang, Bolun

    2018-02-01

    In this work, the influence of Nannochloropsis and Chlorella on the thermal behavior and surface morphology of char during the co-pyrolysis process were explored. Thermogravimetric and iso-conversional methods were applied to analyzing the pyrolytic and kinetic characteristics for different mass ratios of microalgae and low-rank coal (0, 3:1, 1:1, 1:3 and 1). Fractal theory was used to quantitatively determine the effect of microalgae on the morphological texture of co-pyrolysis char. The result indicated that both the Nannochloropsis and Chlorella promoted the release of volatile from low-rank coal. Different synergistic effects on the thermal parameters and yield of volatile were observed, which could be attributed to the different compositions in the Nannochloropsis and Chlorella and operating condition. The distribution of activation energies shows nonadditive characteristics. Fractal dimensions of the co-pyrolysis char were higher than the individual char, indicating the promotion of disordered degree due to the addition of microalgae. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Designed cellulose nanocrystal surface properties for improving barrier properties in polylactide nanocomposites.

    Science.gov (United States)

    Espino-Pérez, Etzael; Bras, Julien; Almeida, Giana; Plessis, Cédric; Belgacem, Naceur; Perré, Patrick; Domenek, Sandra

    2018-03-01

    Nanocomposites are an opportunity to increase the performance of polymer membranes by fine-tuning their morphology. In particular, the understanding of the contribution of the polymer matrix/nanofiller interface to the overall transport properties is key to design membranes with tailored selective and adsorptive properties. In that aim, cellulose nanocrystals (CNC)/polylactide (PLA) nanocomposites were fabricated with chemically designed interfaces, which were ensuring the compatibility between the constituents and impacting the mass transport mechanism. A detailed analysis of the mass transport behaviour of different permeants in CNC/PLA nanocomposites was carried out as a function of their chemical affinity to grafted CNC surfaces. Penetrants (O 2 and cyclohexane), which were found to slightly interact with the constituents of the nanocomposites, provided information on the small tortuosity effect of CNC on diffusive mass transport. The mass transport of water (highly interacting with CNC) and anisole (interacting only with designed CNC surfaces) exhibited non-Fickian, Case II behaviour. The water vapour caused significant swelling of the CNC, which created a preferential pathway for mass transport. CNC surface grafting could attenuate this phenomenon and decrease the water transport rate. Anisole, an aromatic organic vapour, became reversibly trapped at the specifically designed CNC/PLA interface, but without any swelling or creation of an accelerated pathway. This caused the decrease of the overall mass transport rate. The latter finding could open a way to the creation of materials with specifically designed barrier properties by designing nanocomposites interfaces with specific interactions towards permeants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Water-quality data for two surface coal mines reclaimed with alkaline waste or urban sewage sludge, Clarion County, Pennsylvania, May 1983 through November 1989

    Science.gov (United States)

    Dugas, D.L.; Cravotta, C.A.; Saad, D.A.

    1993-01-01

    Water-quality and other hydrologic data for two surface coal mines in Clarion County, Pa., were collected during 1983-89 as part of studies conducted by the U.S. Geological Survey in cooperation with the Pennsylvania Department of Environmental Resources. Water samples were collected from streams, seeps, monitor wells, and lysimeters on a monthly basis to evaluate changes in water quality resulting from the addition of alkaline waste or urban sewage sludge to the reclaimed mine-spoil surface. The mines are about 3.5 miles apart and were mined for bituminous coal of the upper and lower Clarion seams of the Allegheny Group of Pennsylvanian age. The coal had high sulfur (greater than 2 weight percent) concentrations. Acidic mine drainage is present at both mines. At one mine, about 8 years after mining was completed, large quantities (greater than 400 tons per acre) of alkaline waste consisting of limestone and lime-kiln flue dust were applied on two 2.5-acre plots within the 65-acre mine area. Water-quality data for the alkaline-addition plots and surrounding area were collected for 1 year before and 3 years after application of the alkaline additives (May 1983-July 1987). Data collected for the alkaline-addition study include ground-water level, surface-water discharge rate, temperature, specific conductance, pH, and concentrations of alkalinity, acidity, sulfate, iron (total and ferrous), manganese, aluminum, calcium, and magnesium. At the other mine, about 3.5 years after mining was completed, urban sewage sludge was applied over 60 acres within the 150-acre mine area. Waterquality data for the sludge-addition study were collected for 3.5 years after the application of the sludge (June 1986-December 1989). Data collected for the sludge-addition study include the above constituents plus dissolved oxygen, redox potential (Eh), and concentrations of dissolved solids, phosphorus, nitrogen species, sulfide, chloride, silica, sodium, potassium, cyanide, arsenic, barium

  12. Deposition Assessment Of Anthropogenic Airborne 210Po And 210Pb In The Mosses And Surface Soil At The Vicinity Of A Coal-Fired Power Plant

    International Nuclear Information System (INIS)

    Zal U'yun Wan Mahmood; Nita Salina Abu Bakar; Abdul Kadir Ishak

    2014-01-01

    Anthropogenic airborne depositions of 210 Po and 210 Pb in the mosses and surface soil collected at the vicinity of a coal-fired power plant were assessed. The purpose of the study was to determine activity concentrations of 210 Po, 210 Pb and its activity ratio ( 210 Po/ 210 Pb). Other purposes were to determine their concentration factor (CF) in relation to track the potential source of those radionuclides and to identify most suitable moss species as a biological indicator for atmospheric deposition contaminants. In this study, different species of mosses Leucobryum aduncum, Campylopus serratus, Syrrhopodon ciliates and Vesicularia montagnei were collected in May 2011 at the area around 30 km radius from Tanjung Bin coal-fired power plant located in Pontian, Johor. The activity concentrations of 210 Po 210 Pb and 210 Po/ 210 Pb in mosses were in the range of 76.81 ± 4.94 - 251.33 ± 16.33 Bqkg -1 dry wt., 54.37 ± 3.38 - 164.63 ± 11.64 Bqkg -1 dry wt. and 1.10 - 2.00, respectively. Meanwhile the ranges for those radionuclides in the surface soil were 33.53 ± 2.10 - 183.93 ± 12.01 Bqkg -1 dry wt., 17.92 ± 1.18 - 298.60 ± 23.70 Bqkg -1 dry wt. and 1.57 - 2.44, respectively. Corresponding high ability of Leucobryum aduncum to accumulate more 210 Po and 210 Pb, wide geographical distribution, most abundant and high CF, therefore, the findings can be concluded this species was the most suitable as a biological indicator for atmospheric deposition contaminants such as 210 Po and 210 Pb. Furthermore, it is clear the accumulation of 210 Po and 210 Pb in mosses might be supplied from various sources of atmospheric deposition such as coal-fired power plant operation, industrial, agriculture and fertilizer activities, burned fuel fossil and forest; and other potential sources. Meanwhile, the main source of 210 Po and 210 Pb in surface soil is supplied from the in situ decay of radon and radium. (author)

  13. Characterization of gloss properties of differently treated polymer coating surfaces by surface clarity measurement methodology.

    Science.gov (United States)

    Gruber, Dieter P; Buder-Stroisznigg, Michael; Wallner, Gernot; Strauß, Bernhard; Jandel, Lothar; Lang, Reinhold W

    2012-07-10

    With one measurement configuration, existing gloss measurement methodologies are generally restricted to specific gloss levels. A newly developed image-analytical gloss parameter called "clarity" provides the possibility to describe the perceptual result of a broad range of different gloss levels with one setup. In order to analyze and finally monitor the perceived gloss of products, a fast and flexible method also for the automated inspection is highly demanded. The clarity parameter is very fast to calculate and therefore usable for fast in-line surface inspection. Coated metal specimens were deformed by varying degree and polished afterwards in order to study the clarity parameter regarding the quantification of varying surface gloss types and levels. In order to analyze the correlation with the human gloss perception a study was carried out in which experts were asked to assess gloss properties of a series of surface samples under standardized conditions. The study confirmed clarity to exhibit considerably better correlation to the human perception than alternative gloss parameters.

  14. Chemical, mechanical and biological properties of contemporary composite surface sealers.

    Science.gov (United States)

    Anagnostou, Maria; Mountouris, George; Silikas, Nick; Kletsas, Dimitris; Eliades, George

    2015-12-01

    To evaluate the chemical, mechanical, and biological properties of modern composite surface sealers (CSS) having different compositions. The CSS products tested were Biscover LV (BC), Durafinish (DF), G-Coat Plus (GC), and Permaseal (PS). The tests performed were: (A): degree of conversion (DC%) by ATR-FTIR spectroscopy; (B): thickness of O2-inhibition layer by transmission optical microscopy; (C): surface hardness, 10 min after irradiation and following 1 week water storage, employing a Vickers indenter (VHN); (D): color (ΔE*) and gloss changes (ΔGU) after toothbrush abrasion, using L*a*b* colorimetry and glossimetry; (E): accelerated wear (GC,PS only) by an OHSU wear simulator plus 3D profilometric analysis, and (F): cytotoxicity testing of aqueous CSS eluents on human gingival fibroblast cultures employing the methyl-(3)H thymidine DNA labeling method. Statistical analyses included 1-way (A, B, ΔE*, ΔGU) and 2-way (C, F) ANOVAs, plus Tukey post hoc tests. Student's t-test was used to evaluate the results of the accelerated wear test (α=0.05 for all). The rankings of the statistical significant differences were: (A) PS (64.9)>DF,BC,GC (56.1-53.9) DC%; (B) DF,PS (12.3,9.8)>GC,BC (5.2,4.8) μm; (C): GC (37.6)>BC,DF (32.6,31.1)>PS (26.6) VHN (10 min/dry) and BC,DF (29.3,28.7)>GC(26.5)>PS(21.6) VHN (1w/water), with no significant material/storage condition interaction; (D): no differences were found among GC,DF,BC,PS (0.67-1.11) ΔE*, with all values within the visually acceptable range and PS,BC (32.8,29.4)>GC,DF (19.4,12.9) ΔGU; (E): no differences were found between GC and PS in volume loss (0.10,0.11 mm(3)), maximum (113.9,130.5 μm) and mean wear depths (30.3,27.5 μm); (F): at 1% v/v concentration, DF showed toxicity (23% vital cells vs 95-102% for others). However, at 5% v/v concentration DF (0%) and BC (9%) were the most toxic, whereas GC (58%) and PS (56%) showed moderate toxicity. Important chemical, mechanical, and biological properties exist among

  15. A summary of fish and wildlife information needs to surface mine coal in the United States. Part 1. Fish and wildlife information needs in the federal surface mining permanent regulations. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-01-01

    This is part 1 of three part series to assist government agencies and private citizens in determining fish and wildlife information needs for new coal mining operations pursuant to the Surface Mining Control and Reclamation Act of 1977. Part 2 will document status of individual state surface mining regulations as of January 1980 in those states having significant strippable reserves and/or active strip mining operations. It will also provide documentation of fish and wildlife information needs identified in the state regulations of compliance to PL 95-87. Part 3 will be a discussion of the information needed to develop the Fish and Wildlife Plan identified in the Permanent Regulations. The objective of this three part series is to include consideration of fish and wildlife resources in the surface mining process.

  16. Path dependence, fragmented property rights and the slow diffusion of high throughput technologies in inter-war British coal mining

    Energy Technology Data Exchange (ETDEWEB)

    Peter Scott

    2006-01-15

    This article examines the importance of path dependence effects in impeding the diffusion of high throughput mechanized mining systems in the British coal industry. It demonstrates that the industry had become 'locked in' to low throughput underground haulage technology, on account of institutional interrelatedness between Britain's traditional practice of extensive in-seam mining and its unique system of fragmented, privately owned mineral royalties. Fragmented royalties prevented the concentration of workings and introduction of high throughput main haulage systems that underpinned the rapid productivity growth of European producers. Meanwhile, technical interrelatedness between the haulage systems taking coal to the pit shaft and operations further 'upstream' created bottlenecks which both slowed the overall rate of mechanization and limited the productivity gains from the mechanization that did occur.

  17. Converting coal

    Energy Technology Data Exchange (ETDEWEB)

    Avigliano, A. [Bedeschi (Italy)

    2006-10-15

    In September 2005, Bedeschi was commissioned to design and supply a coal unloading, conveying and storage facility for a new raw coal line system within Hatien II Cement Co. The new plant is composed of a grab unloader, a conveyor system, a storage shed with stacking and reclaiming facilities, a complete dedusting system and civil and steel structure engineering. The scope of supply includes a local fabrication portion; however, main components will be imported. The project will be completed in 21 months. The paper looks into the mechanics of loading and unloading coal. 4 figs., 4 photos.

  18. Validation of a laboratory method for evaluating dynamic properties of reconstructed equine racetrack surfaces.

    Directory of Open Access Journals (Sweden)

    Jacob J Setterbo

    Full Text Available Racetrack surface is a risk factor for racehorse injuries and fatalities. Current research indicates that race surface mechanical properties may be influenced by material composition, moisture content, temperature, and maintenance. Race surface mechanical testing in a controlled laboratory setting would allow for objective evaluation of dynamic properties of surface and factors that affect surface behavior.To develop a method for reconstruction of race surfaces in the laboratory and validate the method by comparison with racetrack measurements of dynamic surface properties.Track-testing device (TTD impact tests were conducted to simulate equine hoof impact on dirt and synthetic race surfaces; tests were performed both in situ (racetrack and using laboratory reconstructions of harvested surface materials. Clegg Hammer in situ measurements were used to guide surface reconstruction in the laboratory. Dynamic surface properties were compared between in situ and laboratory settings. Relationships between racetrack TTD and Clegg Hammer measurements were analyzed using stepwise multiple linear regression.Most dynamic surface property setting differences (racetrack-laboratory were small relative to surface material type differences (dirt-synthetic. Clegg Hammer measurements were more strongly correlated with TTD measurements on the synthetic surface than the dirt surface. On the dirt surface, Clegg Hammer decelerations were negatively correlated with TTD forces.Laboratory reconstruction of racetrack surfaces guided by Clegg Hammer measurements yielded TTD impact measurements similar to in situ values. The negative correlation between TTD and Clegg Hammer measurements confirms the importance of instrument mass when drawing conclusions from testing results. Lighter impact devices may be less appropriate for assessing dynamic surface properties compared to testing equipment designed to simulate hoof impact (TTD.Dynamic impact properties of race surfaces

  19. Tailoring Novel PTFE Surface Properties: Promoting Cell Adhesion and Antifouling Properties via a Wet Chemical Approach.

    Science.gov (United States)

    Gabriel, Matthias; Niederer, Kerstin; Becker, Marc; Raynaud, Christophe Michel; Vahl, Christian-Friedrich; Frey, Holger

    2016-05-18

    Many biomaterials used for tissue engineering applications lack cell-adhesiveness and, in addition, are prone to nonspecific adsorption of proteins. This is especially important for blood-contacting devices such as vascular grafts and valves where appropriate surface properties should inhibit the initial attachment of platelets and promote endothelial cell colonization. As a consequence, the long-term outcome of the implants would be improved and the need for anticoagulation therapy could be reduced or even abolished. Polytetrafluoroethylene (PTFE), a frequently used polymer for various medical applications, was wet-chemically activated and subsequently modified by grafting the endothelial cell (EC) specific peptide arginine-glutamic acid-aspartic acid-valine (REDV) using a bifunctional polyethylene glycol (PEG)-spacer (known to reduce platelet and nonspecific protein adhesion). Modified and control surfaces were both evaluated in terms of EC adhesion, colonization, and the attachment of platelets. In addition, samples underwent bacterial challenges. The results strongly suggested that PEG-mediated peptide immobilization renders PTFE an excellent substrate for cellular growth while simultaneously endowing the material with antifouling properties.

  20. Rehabilitation materials from surface- coal mines in western U.S.A. III. Relations between elements in mine soil and uptake by plants.

    Science.gov (United States)

    Severson, R.C.; Gough, L.P.

    1984-01-01

    Plant uptake of Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn from mine soils was assessed using alfalfa Medicago sativa, sainfoin Onobrychis viciaefolia, smooth brome Bromus inermis, crested wheatgrass Agropyron cristatum, slender wheatgrass A. trachycaulum and intermediate wheatgrass A. intermedium; mine soil (cover-soil and spoil material) samples were collected from rehabilitated areas of 11 western US surface-coal mines in North Dakota, Montana, Wyoming and Colorado. Correlations between metals in plants and DTPA-extractable metals from mine soils were generally not statistically significant and showed no consistent patterns for a single metal or for a single plant species. Metal uptake by plants, relative to amounts in DTPA extracts of mine soil, was positively related to mine soil organic matter content or negatively related to mine soil pH. DTPA-extractable metal levels were significantly correlated with mine soil pH and organic-matter content.-from Authors

  1. Possibilities for using emulsion explosives in the Pljevlja coal surface mine. Mogucnost primjene emulzionih eksploziva na povrsinskim kopovima rudnika uglja Pljevlja

    Energy Technology Data Exchange (ETDEWEB)

    Memic, M.; Pejatovic, Z.; Rocen, V. (Rudnik Uglja, Pljevlja (Yugoslavija))

    1990-01-01

    Conducts experimental blasting experiments with ANFO and slurry explosives in the Potrlica surface mine (Yugoslavia). The study aimed at assessing the possibility of reducing overburden removal cost by replacing conventional solid explosives. Effects of experimental fragmentation blasting of marlstone layers in the overburden of this mine in the Pljevlja coal basin are described. Multi-row delayed blasting (4 rows, 85 boreholes with 115 mm diameter) was carried out on a 10 m high working bench. A total of 7,855 kg of slurry DETOLIT PEM explosive, mixed on the spot and strengthened with aluminium powder, were pumped into boreholes and activated by boosters. The effects of experimental blasting are regarded as promising in respect to fragmentation of blasted material, lower seismic effects and cost (30% less than that of conventional explosives).

  2. Slagging behavior of upgraded brown coal and bituminous coal in 145 MW practical coal combustion boiler

    Energy Technology Data Exchange (ETDEWEB)

    Akiyama, Katsuya; Pak, Haeyang; Takubo, Yoji [Kobe Steel, Ltd, Kobe (Japan). Mechanical Engineering Research Lab.; Tada, Toshiya [Kobe Steel, Ltd, Takasago (Japan). Coal and Energy Technology Dept.; Ueki, Yasuaki [Nagoya Univ. (Japan). Energy Science Div.; Yoshiie, Ryo; Naruse, Ichiro [Nagoya Univ. (Japan). Dept. of Mechanical Science and Engineering

    2013-07-01

    The purpose of this study is to quantitatively evaluate behaviors of ash deposition during combustion of Upgraded Brown Coal (UBC) and bituminous coal in a 145 MW practical coal combustion boiler. A blended coal consisting 20 wt% of the UBC and 80 wt% of the bituminous coal was burned for the combustion tests. Before the actual ash deposition tests, the molten slag fractions of ash calculated by chemical equilibrium calculations under the combustion condition was adopted as one of the indices to estimate the tendency of ash deposition. The calculation results showed that the molten slag fraction for UBC ash reached approximately 90% at 1,523 K. However, that for the blended coal ash became about 50%. These calculation results mean that blending the UBC with a bituminous coal played a role in decreasing the molten slag fraction. Next, the ash deposition tests were conducted, using a practical pulverized coal combustion boiler. A water-cooled stainless-steel tube was inserted in locations at 1,523 K in the boiler to measure the amount of ash deposits. The results showed that the mass of deposited ash for the blended coal increased and shape of the deposited ash particles on the tube became large and spherical. This is because the molten slag fraction in ash for the blended coal at 1,523 K increased and the surface of deposited ash became sticky. However, the mass of the deposited ash for the blended coal did not greatly increase and no slagging problems occurred for 8 days of boiler operation under the present blending conditions. Therefore, appropriate blending of the UBC with a bituminous coal enables the UBC to be used with a low ash melting point without any ash deposition problems in a practical boiler.

  3. Soil properties and clover establishment six years after surface application of calcium-rich by-products

    Energy Technology Data Exchange (ETDEWEB)

    Ritchey, K.D.; Belesky, D.P.; Halvorson, J.J. [USDA ARS, Beaver, WV (US). Appalachian Farming Systems Research Center

    2004-12-01

    Calcium-rich soil amendments can improve plant growth by supplying Ca and reducing detrimental effects of soil acidity, but solubility and neutralizing capacity of Ca sources vary. Our objectives were to evaluate effects of calcitic dolomite and several coal combustion by-products on soil properties at various depths 6 yr after surface application and their influence on grass-clover herbage accumulation. Calcium and Mg soil amendments were surface-applied to an acidic grassland in 1993, and orchardgrass (Dactylis glomerata L.) and tall fescue (Lolium arundinaceum (Schreb.) Darbyshire) were oversown in 1994. In 1998, amendment treatment plots were split to accommodate sod seeding with red clover (Trifolium pratense L.) or white clover (T. repens L.) as well as a nonseeded control. No N fertilizer was applied after sod seeding. Six years after amendment application, reductions in soil Al and Mn and increases in Ca and pH from 4654 kg ha{sup -1} calcitic dolomite, 15 000 kg ha{sup -1} fluidized bed combustion residue, or 526 kg ha{sup -1} MgO amendment were greatest in the surface 2.5 cm while rates of gypsum as high as 32 000 kg ha{sup -1} left little residual effect except for decreases in Mg. Percentage clover in the sward tripled as pH increased from 4.3 to 5.0 while herbage mass increased 75% as clover percentage increased. Herbage mass was generally more closely correlated with properties of soil samples collected from the surface 2.5 cm than from deeper samples.

  4. Geological storage of carbon dioxide in the coal seams: from material to the reservoir

    International Nuclear Information System (INIS)

    Nikoosokhan, S.

    2012-01-01

    CO 2 emissions into the atmosphere are recognized to have a significant effect on global warming. Geological storage of CO 2 is widely regarded as an essential approach to reduce the impact of such emissions on the environment. Moreover, injecting carbon dioxide in coal bed methane reservoirs facilitates the recovery of the methane naturally present, a process known as enhanced coal bed methane recovery (ECBM). But the swelling of the coal matrix induced by the preferential adsorption by coal of carbon dioxide over the methane in place leads to a closure of the cleat system (a set of small natural fractures) of the reservoir and therefore to a loss of injectivity. This PhD thesis is dedicated to a study of how this injectivity evolves in presence of fluids. We derive two poro-mechanical dual-porosity models for a coal bed reservoir saturated by a pure fluid. The resulting constitutive equations enable to better understand and model the link between the injectivity of a coal seam and the adsorption-induced swelling of coal. For both models, the pore space of the reservoir is considered to be divided into the macroporous cleats and the pores of the coal matrix. The two models differ by how adsorption of fluid is taken into account: the first model is restricted to surface adsorption, while the second model can be applied for adsorption in a medium with a generic pore size distribution and thus in a microporous medium such as coal, in which adsorption mostly occurs by micropore filling. The latter model is calibrated on two coals with different sorption and swelling properties. We then perform simulations at various scales (Representative Elementary Volume, coal sample, coal seam). In particular, we validate our model on experimental data of adsorption-induced variations of permeability of coal. We also perform simulations of seams from which methane would be produced (CBM) or of methane-free seams into which CO 2 would be injected. We study the effect of various

  5. Coal competitiveness?

    International Nuclear Information System (INIS)

    Rogeaux, B.

    2006-01-01

    Will coal electrical plants be more competitive in the coming years? Answering this one cannot be limited to merely comparing estimates based on reference electricity production costs. The competitiveness of coal will indeed depend on the final product marketed, as the MWhs are not equal: is the purpose to produce base, half-base MWh? Does the electrical equipment structure require flexible MWh (for instance in the event of significant intermittent renewable energy amounts), and therefore plants able to adjust their power rapidly? But the competitiveness of coal will also depend on many factors that will correct reference cost estimates: uncertainties, risks, externalities. These factors will need to be appreciated on a case by case basis. We introduce some of the reasoning used to better appreciate the future competitiveness of coal, and the main factors conditioning it in three contrasting regions of the world: Europe, USA, china. (author)

  6. Evaluating non-stick properties of different surface materials for contact frying

    DEFF Research Database (Denmark)

    Ashokkumar, Saranya; Adler-Nissen, Jens

    2011-01-01

    to evaluate non-stick and cleaning properties of the coatings. In accordance with industry standards pancake was selected as the food model for the non-stick properties. The performance of different frying surfaces (stainless steel, aluminium, PTFE (polytetrafluoroethylene) and three ceramic coatings with two...... on their non-stick properties, so that the smoother surfaces gave a higher force of adhesion between pancake and surface....

  7. Coal - 97

    International Nuclear Information System (INIS)

    Sparre, C.

    1997-01-01

    The report deals with the use of coal and coke during 1996. Some information about techniques, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from SCB have also been used. The use of steam coal for heating purposes during 1996 was 1,2 mill tons and 50% higher than in 1995. The increase is probably temporary and due to high prices of electricity because of lack of water power. The co-generation plants were the main users of coal. The minor plants have increased their use of forest fuels. Probably the use of steam coal will go down in the immediate years both in the heat generating and the co-generation plants. During the top year 1987 coal was used in 18 hotwater plants and 11 co-generation plants. 1996 these figures are 3 and 12. Taxes and environmental reasons explain this trend. The use of steam coal in the industry has been constant at the level 700 000 tons. This level is supposed to be constant or to vary with business cycles. The import of metallurgical coal in 1996 was 1,6 mill tons like the year before. 1,2 mill tons coke were produced. The coke consumption in the industry was 1,5 mill tons. 0,3 mill tons of coke were imported. The average price of steam coal imported in Sweden in 1996 was 340 SEK/ton or 2% higher than in 1995. For the world, the average import price was 51,5 USD/ton, nearly the same as the year before. The contract prices for delivery during 1997 are about equal as the end of 1996. All Swedish plants meet their emission limits of dust, SO 2 and NO x given by county administrations or concession boards

  8. Estimation of water-coal surface interaction during heat treatment of coal by use of FTir and DSC; FTir to DSC wo mochiita sekitan-mizu kan sogo sayo no teiryoteki hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Miura, K.; Mae, K.; Morozumi, F.; Kusakawa, T. [Kyoto University, Kyoto (Japan)

    1997-10-30

    The authors have recently presented a method to estimate the strength distribution of hydrogen bondings in coal using FTir and DSC. The method was applied to estimate the strength of coal-water interaction in two different coals and to estimate the enthalpy change deriving from the change in hydrogen bondings during the desorption of water. The estimated enthalpy change was compared with the total enthalpy change estimated by DSC measurement to examine the importance of hydrogen bondings during the desertion of water. 1 ref., 6 figs.

  9. Thermodynamic and surface properties of Sb–Sn and In–Sn liquid ...

    Indian Academy of Sciences (India)

    properties through the activity coefficients of the alloy components in the bulk. .... In the model for studying surface properties, a statistical mechanical approach .... experimental values of Scc(0) determined by fitting the experimental activity ...

  10. Model of coordination melting of crystals and anisotropy of physical and chemical properties of the surface

    Science.gov (United States)

    Bokarev, Valery P.; Krasnikov, Gennady Ya

    2018-02-01

    Based on the evaluation of the properties of crystals, such as surface energy and its anisotropy, the surface melting temperature, the anisotropy of the work function of the electron, and the anisotropy of adsorption, were shown the advantages of the model of coordination melting (MCM) in calculating the surface properties of crystals. The model of coordination melting makes it possible to calculate with an acceptable accuracy the specific surface energy of the crystals, the anisotropy of the surface energy, the habit of the natural crystals, the temperature of surface melting of the crystal, the anisotropy of the electron work function and the anisotropy of the adhesive properties of single-crystal surfaces. The advantage of our model is the simplicity of evaluating the surface properties of the crystal based on the data given in the reference literature. In this case, there is no need for a complex mathematical tool, which is used in calculations using quantum chemistry or modeling by molecular dynamics.

  11. Investigation of surface properties of physico-chemically modified natural fibres using inverse gas chromatography

    CSIR Research Space (South Africa)

    Cordeiro, N

    2011-01-01

    Full Text Available Inverse gas chromatography (IGC) is a suitable method to determine surface energy of natural fibres when compared to wetting techniques. In the present study, the surface properties of raw and modified lignocellulosic fibres have been investigated...

  12. Geotechnical properties of surface sediments in the INDEX area

    Digital Repository Service at National Institute of Oceanography (India)

    Khadge, N.H.

    As a part of the environmental impact assessment studies, geotechnical properties of sediments were determined in the Central Indian Basin. The undrained shear strength and index properties of the siliceous sediments were determined on 20 box cores...

  13. Surface morphology, structural and electrical properties of RF ...

    Indian Academy of Sciences (India)

    2018-05-19

    May 19, 2018 ... ITO thin films; sputtering; structure; electrical properties; AFM; Hall effect. 1. Introduction ... ness range (61–768 nm) and to see if this system present properties that .... using the Bragg equation, and the relation linking the inter-.

  14. Determination of Mechanical and Surface Properties of Semicrystalline Polyhedral Oligomeric Silsesquioxane (POSS) Nanocomposites

    National Research Council Canada - National Science Library

    Moody, Laura E; Marchant, Darrell; Grabow, Wade W; Lee, Andre Y; Mabry, Joseph M

    2005-01-01

    INTRODUCTION: (1) Nanomodification of semicrystalline polymers -- unequalled thermal, mechanical and surface properties at low volume fractions that cannot be obtained using conventional fillers; (2...

  15. Determination of Mechanical and Surface Properties of Semicrystalline Polyhedral Oligomeric Silsequioxane (POSS) Nanocomposites

    National Research Council Canada - National Science Library

    Moody, Laura E; Marchant, Darrell; Grabow, Wade W; Lee, Andre Y; Mabry, Joseph M

    2005-01-01

    .... This study examines the ability of POSS to improve the mechanical and surface properties of three semicrystalline polymers, fluorinated ethylene-propylene (FEP), poly(vinylidene fluoride) (PVDF...

  16. Indian coal industry: Growth perspective

    International Nuclear Information System (INIS)

    Sachdev, R.K.

    1993-01-01

    Growth perspective of Indian coal industry and their environmental aspects, are discussed. The complete coal chain comprises of mining including preparation and processing, transport, usage and disposal of solid, liquid and gaseous wastes. Proper environmental protection measures are therefore, required to be integrated at every stage. At mining stage, land reclamation, restoration of surface damaged by subsidence and proper treatment of effluents are the minimum requirement for effective environmental protection. Since coal will continue to be the major source of commercial energy in coming decades initiative will have to be taken in making coal a clean fuel from the point of view of its usage in different industries. Washing of high ash coals for reducing the ash content will go a long way in reducing the atmospheric pollution through better plant performance and reduced environmental pollution at the power plants. (author)

  17. Steam coal processing technology: handling, high-order processing, COM, meth-coal

    Energy Technology Data Exchange (ETDEWEB)

    Kamata, H.; Onodera, J.

    1982-01-01

    Topics covered include: various handling techologies (overland and marine transport, storage, water removal, drying, comminution and sizing); various coal processing technologies (gravity concentration, magnetic separation, multi-stage flotation, liquid-phase pelletizing, chemical processing); production methods for coal-oil mixtures (COM), their physical properties, stability, storage, transport, advantages, plus recent trends in research and development; production of coal-methanol slurry (meth-coal), its stability, storage, transport, utilization and environmental problems, plus latest trends in research and development. (In Japanese)

  18. Adsorption isotherms and kinetics of activated carbons produced from coals of different ranks.

    Science.gov (United States)

    Purevsuren, B; Lin, Chin-Jung; Davaajav, Y; Ariunaa, A; Batbileg, S; Avid, B; Jargalmaa, S; Huang, Yu; Liou, Sofia Ya-Hsuan

    2015-01-01

    Activated carbons (ACs) from six coals, ranging from low-rank lignite brown coal to high-rank stone coal, were utilized as adsorbents to remove basic methylene blue (MB) from an aqueous solution. The surface properties of the obtained ACs were characterized via thermal analysis, N2 isothermal sorption, scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and Boehm titration. As coal rank decreased, an increase in the heterogeneity of the pore structures and abundance of oxygen-containing functional groups increased MB coverage on its surface. The equilibrium data fitted well with the Langmuir model, and adsorption capacity of MB ranged from 51.8 to 344.8 mg g⁻¹. Good correlation coefficients were obtained using the intra-particle diffusion model, indicating that the adsorption of MB onto ACs is diffusion controlled. The values of the effective diffusion coefficient ranged from 0.61 × 10⁻¹⁰ to 7.1 × 10⁻¹⁰ m² s⁻¹, indicating that ACs from lower-rank coals have higher effective diffusivities. Among all the ACs obtained from selected coals, the AC from low-rank lignite brown coal was the most effective in removing MB from an aqueous solution.

  19. Coal -98

    International Nuclear Information System (INIS)

    Sparre, C.

    1998-01-01

    The following report deals with the use of coal and coke during 1997. Some information about technic, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from SCB have also been used. The use of steam coal for heating purposes during 1997 was 730 000 tons and about 500 000 tons lower than in 1996. The extremely high figures of 1996 were due to twice the production of electricity because of lack of hydro power. The co-generation plants were the main users of coal. The minor plants have increased their use of forest fuels. Probably the use of steam coal will go down in the immediate years both in the heat generating and the co-generating plants. Some foreign analysts, however, estimate a doubled use of coal for energy use after 2020 because of the plans to phase out the nuclear power. During the top year 1987 coal was used in 18 hot water plants and 11 co-generation plants. 1997 these figures are 2 and 8. Taxes and environmental reasons explain this trend. The use of steam coal in the industry has been constant at the level 700 000 tons. This level is supposed to be constant or to vary with business cycles. The import of metallurgical coal in 1997 was 1.6 mill tons like the year before. 1.2 mill tons coke were produced. The coke consumption in the industry was 1.5 Mill tons. 0.3 mill tons of coke were imported. Several other plants have plans to replace the coal with forest fuels, waste fuels and NG. Even the biggest plant, Vaesteraas, has plans to build a block for bio fuels. Helsingborg has started to use wood pellets. The pellets replace most of the coal for the heat production in the co-generation plant. Norrkoeping Kraft AB has taken a fluid bed boiler for different fuels in operation, leading to more than half the coal consumption compared with previous years. They have also rebuilt one of their travelling grates for bio fuels. Stockholm

  20. German planning atlas. Vol. 1: North Rhine Westphalia. No. 11. Brown coal 2 - ownership of brown coal deposits, resettlement, surface balance, coal, rock, and energy economy, future developments. Deutscher Planungsatlas. Bd. 1: Nordrhein-Westfalen. Nr. 11. Braunkohle 2 - Feldesbesitz, Umsiedlung, Grundwasser, Flaechenbilanz, Kohle-, Abraum- und Energiewirtschaft, kuenftige Entwicklung

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    In map No. III of the atlas on the develpment of Rhenish coal mining, the ownership in brown coal deposits and planning, resettlement, ground water and an area balance are presented. Map No. IV discusses coal economy, rock economy, energy economy, structure and development. Details are described in the text.

  1. Control and evaluation methodology of reclaimed surfaces in coal mines; Metodologia para el Seguimiento y Evaluacion de Superficies Restauradas en Minas de Carbon

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The objective of the project has been to establish a control and evaluation methodology of reclaimed surfaces in coal mines, ash dumps,... etc. to be applied especially in locations with limited availability of ton soil, and to be used by mining companies to establish an internal quality control of the reclamation carried out. This methodology has been developed based on the evaluation of the results obtained from the reclamation that Endesa carries out at the Puentes mine. An operating and simplified method which may be adopted by smaller sites has been developed. This project has been carried out during the period 1994-1996 and includes a study about the physicochemical conditions of reclaimed surfaces, soil organisms study and about vegetation productivity associated to micorrizae. The conclusions and recommendations obtained include reclamation techniques (study and management of the deposit dumped, top soil management, addition of basic correctors, fertilization, top soil and maintenance works) and reclaimed surface control techniques (physicochemical soil conditions, soil organisms and vegetation). (Author)

  2. Modeling the Acid-Base Properties of Montmorillonite Edge Surfaces.

    Science.gov (United States)

    Tournassat, Christophe; Davis, James A; Chiaberge, Christophe; Grangeon, Sylvain; Bourg, Ian C

    2016-12-20

    The surface reactivity of clay minerals remains challenging to characterize because of a duality of adsorption surfaces and mechanisms that does not exist in the case of simple oxide surfaces: edge surfaces of clay minerals have a variable proton surface charge arising from hydroxyl functional groups, whereas basal surfaces have a permanent negative charge arising from isomorphic substitutions. Hence, the relationship between surface charge and surface potential on edge surfaces cannot be described using the Gouy-Chapman relation, because of a spillover of negative electrostatic potential from the basal surface onto the edge surface. While surface complexation models can be modified to account for these features, a predictive fit of experimental data was not possible until recently, because of uncertainty regarding the densities and intrinsic pK a values of edge functional groups. Here, we reexamine this problem in light of new knowledge on intrinsic pK a values obtained over the past decade using ab initio molecular dynamics simulations, and we propose a new formalism to describe edge functional groups. Our simulation results yield reasonable predictions of the best available experimental acid-base titration data.

  3. Effect of microwave radiation on coal flotation

    Energy Technology Data Exchange (ETDEWEB)

    Ozbayoglu, G.; Depci, T.; Ataman, N. [Middle East Technical University, Ankara (Turkey). Mining Engineering Department

    2009-07-01

    Most low-rank coals are high in moisture and acid functional groups, therefore showing poor floatability. Drying, which removes the water molecules trapped in the pores and adsorbed at the surface of coal, decreases the hydrophilic character and improves the floatability. Microwave heating, whose simplest application is drying, was applied at 0.9 kW power level for 60 sec exposure time in the experiments to decrease the moisture content of coal in order to enhance the hydrophobicity. The flotation tests of microwave-treated coal by using heptanol and octanol lead to a higher flotation yield and ash removal than original coal.

  4. Effect of properties of iron compounds on the catalytic activity in direct coal liquefaction; Tetsu kagobutsu no keitai to sekitan ekika kassei

    Energy Technology Data Exchange (ETDEWEB)

    Kaneko, T.; Tazawa, K. [Mitsubishi Chemical Corp., Tokyo (Japan); Shimasaki, K. [Kobe Steel Ltd. (Japan)

    1998-08-20

    When considering merchandising scale of the coal liquefaction process, it is a preliminary condition that metal used for its catalyst is rich in resource volume, cheap in production cost, without pollution, and so forth, and application of cheap iron ore and ferrous compounds to disposable catalyst is desired. As liquefaction activity of the iron ore was hitherto improved by its micro crushing, its mechanical crush had a limit of about 2 {mu}m in mean particle diameter. However, together with recent crushing technique, crushers with high performance were developed, and then micro crushing by sub-micron became possible industri8ally even for iron ore. In this study, three kinds of Australian iron ores such as limonite of ferric hydroxide type iron ore, pyrite of ferrous sulfide type, and hematite of ferric oxide type were micro crushed to examine coal liquefaction activity and hydrogenation reaction activity of 1-methyl naphthalene (1-MN) and also relationship between properties and activity of catalyst for the latter before and after reaction. 11 refs., 8 figs., 5 tabs.

  5. The defect-induced changes of the electronic and magnetic properties in the inverse Heusler alloy Ti{sub 2}CoAl

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying, E-mail: ychenjz@163.com [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China); Wu, Bo [Department of Physics, Zunyi Normal College, Zunyi 563002 (China); Yuan, Hongkuan; Feng, Yu [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China); Chen, Hong, E-mail: chenh@swu.edu.cn [School of Physical Science and Technology, Southwest University, Chongqing 400715 (China)

    2015-01-15

    The first-principles calculations are performed to investigate the effect of swap, antisite and vacancy defects of three classes on the electronic and magnetic properties in the inverse Heusler alloy Ti{sub 2}CoAl of half-metallicity. Our calculations reveal that Ti(A/B)–Co and Co–Al swaps, Ti(A/B) and Al vacancy defects as well as Co{sub Ti(A)/Al} and Al{sub Ti(A)/Ti(B)} antisite defects are likely to form in a concentration as high as 12.5%. Among them, Co{sub Ti(A)} antisite is detected to be the most probable defect. It is shown that the spin polarizations of Ti{sub 2}CoAl are considerably reduced by the Ti(A/B)–Co swap and Ti(B)/Al vacancy defects, while a quite high spin polarization around 95% is observed in Co–Al swap as well as Ti(A) vacancy. Remarkably, all the likely antisite defects almost retain the half-metallic character in a concentration of 12.5% even if they have the possibility to form. However, induced by antisites, the Fermi levels shift to the edge of band gap with small peaks arising just above the Fermi level, which may destroy the half-metallicity by spin-flip excitation. - Graphical abstract: The spin polarization and formation energy of various possible defects in inverse Heusler alloy Ti{sub 2}CoAl. The triangle, star and square represent the swap, antisite and vacancy defects, respectively. - Highlights: • The swap, antisite, and vacancy defects are studied in half-metallic Ti{sub 2}CoAl. • The Co{sub Ti(A)} antisite is the most probable among the studied defects. • The antisite defects almost retain the half-metallicity. • Most of swap and vacancy defects have degraded the half-metallicity. • High spin polarizations are detected in Co–Al swap and Ti(A) vacancy defects.

  6. Emission and properties of NO{sub x} generated during coal grate-fired in O{sub 2}/N{sub 2}/CO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Li; Gao, Jian-min; Zhao, Lai-fu; Zhao, Guang-bo; Wu, Shaohua [Harbin Institute of Technology, Harbin (China). Combustion Engineering Research Inst.

    2013-07-01

    With the improvement of environmental protection requirements, the problems of NO{sub x} emission from industrial boiler become more and more notable. Flue gas recirculation is a low-NO{sub x} combustion technology. It draws out a part of the flue gas from rear flue and forces it into boiler. So the flue gas can serve the combustion or flow field integration. The drawn flue gas can be forced into the boiler directly, or mixed with the primary air or secondary air. To explore a real effective method of low NO{sub x} combustion, the article discusses the influence of flue gas recirculation on the formation of NO{sub x} in the process of coal grate-fired, in the way of using the unit-boiler, measuring the temperature of coal surface and composition and other important influential parameters. Experimental studies show that under the condition of grate-fired, taking Flue gas recirculation in main combustion zone, coke combustion zone and burn-out zone could notably diminish the amount of NO. And with the promotion of flue gas recirculation rate, the effect can be more noticeable.

  7. Properties of surface waves in granular media under gravity

    International Nuclear Information System (INIS)

    Zheng He-Peng

    2014-01-01

    Acoustical waves propagating along the free surface of granular media under gravity are investigated in the framework of elasticity theory. The influence of stress on a surface wave is analyzed. The results have shown that two types of surface waves, namely sagittal and transverse modes exist depending on initial stress states, which may have some influence on the dispersion relations of surface waves, but the influence is not great. Considering that the present experimental accuracy is far from distinguishing this detail, the validity of elasticity theory on the surface waves propagating in granular media can still be maintained. (electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics)

  8. Coal 95

    International Nuclear Information System (INIS)

    Sparre, C.

    1995-01-01

    The report deals with the use of coal and coke in Sweden during 1994. Some information about technology, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from Statistics Sweden have also been used.The use of steam coal for heating purposes has been unchanged during 1994 at a level of 1 Mtons. The production in the cogeneration plants has been constant, but has increased for electricity production. The minor plants have increased their use of forest fuels. The use of steam coal will probably go down in the next years both for heat and cogeneration plants. During the top year 1987 coal was used in 18 hot water and 11 cogeneration plants. 1994 these figures are 3 and 12. Taxes and environmental reasons explain this trend. The use of steam coal in industry has been constant at the level 0.7 Mtons. The import of metallurgical coal in 1993 was 1.6 Mtons, like 1992. Import of 0.3 Mtons of coke gives the total consumption of coke in industry as 1.5 Mtons. the average price of steam coal imported to Sweden was 317 SEK/ton, 3% higher than 1993. All Swedish plants meet their emission limit of dust, SO 2 and NO x as given by county administrations or concession boards. The cogeneration plants all have some SO 2 removal system. The biggest cogeneration plant (Vaesteraas) has recently invested in a SCR NO x cleaning system. Most other plants use low NO x burners or SNR injection systems based on ammonia or urea. 2 figs, 13 tabs

  9. Volatilisation of aromatic hydrocarbons from soil: part II, fluxes from coal tar contaminated soils residing below the soil surface

    International Nuclear Information System (INIS)

    Lindhardt, B.; Christensen, T.H.

    1996-01-01

    The non-steady-state fluxes of aromatic hydrocarbons from coal tar contaminated soil, placed below a 5 cm deep layer of uncontaminated soil, were measured in the laboratory over a period of 53 days. The contaminated soil originated from a former gasworks site and contained concentrations of 11 selected aromatic hydrocarbons between 50 to 840 μg/cm 3 . Where the microbial activity was inhibited, the fluxes stabilized on a semi-steady-state level for the monocyclic aromatic hydrocarbons, naphthalene and 1-methylnaphthalene after a period of 10-20 days. Fluxes of acenaphthene and fluorene were only measurable in an experiment that utilized a cover soil with a low organic content. The fluxes were predicted by a numerical model assuming that the compounds acted independently of each other and that local equilibrium between the air, water, and sorbed phases existed. The model overestimated the fluxes for all the detected aromatic hydrocarbons by a factor of 1.3 to 12. When the cover soil was adapted to degrade naphthalene, the fluxes of naphthalene and 1-methylnaphthalene approached the detection limit after 5 to 8 days. Thereafter the fluxes of these two compounds were less than predicted by the model employing half-life values of 0.5 and 1 day for naphthalene and 1-methylnaphthalene respectively. 10 refs., 6 figs., 7 tabs

  10. Off-line image analysis for froth flotation of coal

    Energy Technology Data Exchange (ETDEWEB)

    Citir, C.; Aktas, Z.; Berber, R. [Ankara University, Ankara (Turkey). Faculty of Engineering

    2004-05-15

    Froth flotation is an effective process for separating sulphur and fine minerals from coal. Such pre-cleaning of coal is necessary in order to reduce the environmental and operational problems in power plants. The separation depends very much on particle surface properties, and the selectivity can be improved by addition of a reagent. Image analysis can be used to determine the amount of reagent, by using the relation between surface properties and froth bubble sizes. This work reports some improvements in the efficiency of the image analysis, and in determination of bubble diameter distribution towards developing froth-based flotation models. Ultimate benefit of the technique would allow a pre-determined reagent addition profile to be identified for controlling the separation process.

  11. Quality aspects of thermal coal marketing

    International Nuclear Information System (INIS)

    Dunstone, D.

    1998-01-01

    Australia's thermal coal industry is under increasing competition. A successful marketing strategy must distinguish the product from that of Australian competitors, leaving the buyer in no doubt as to its value. The marketing of thermal coal is a very different experience and encompasses an interesting commercial and technical mix. The technical merits of a coal may be effectively used to prepare the way for a sale. However, once the technical hurdle is passed (i.e. the coal is classified as acceptable), the three factors which influence the sale are price, price and price. The other aspect of marketing is that marketing, especially technical market support, must realize that the buyer often has no experience in using the coals purchased. This is particularly true with thermal coals. Virtually no thought is given as to how the coal performs or how much is used. Consequently, it is not uncommon for cheap, low quality coals to be purchased, even though it is not the choice that will result in the lowest power generation cost when all other factors are taken into consideration. The author has developed a model which allows to differentiate between coals for a range of properties relative to the use of the coal, so that a coal company can calculate the break-even price in term of cost per kWh of electricity generated and enable a more valid cost comparison between coals to be made

  12. Friction Surface Treatment Selection: Aggregate Properties, Surface Characteristics, Alternative Treatments, and Safety Effects

    Science.gov (United States)

    2017-07-01

    This study aimed to evaluate the long term performance of the selected surface friction treatments, including high friction surface treatment (HFST) using calcined bauxite and steel slag, and conventional friction surfacing, in particular pavement pr...

  13. Hydrology of the Ferron sandstone aquifer and effects of proposed surface-coal mining in Castle Valley, Utah, with sections on stratigraphy and leaching of overburden

    Science.gov (United States)

    Lines, Gregory C.; Morrissey, Daniel J.; Ryer, Thomas A.; Fuller, Richard H.

    1983-01-01

    Coal in the Ferron Sandstone Member of the Mancos Shale of Cretaceous age has traditionally been mined by underground techniques in the Emery Coal Field in the southern end of Castle Valley in east-central Utah. However, approximately 99 million tons are recoverable by surface mining. Ground water in the Ferron is the sole source of supply for the town of Emery, but the aquifer is essentially untapped outside the Emery area.The Ferron Sandstone Member crops out along the eastern edge of Castle Valley and generally dips 2 ? to 10 ? to the northwest. Sandstones in the Ferron are enclosed between relatively impermeable shale in the Tununk and Blue Gate Members of the Mancos Shale. Along the outcrop, the Ferron ranges in thickness from about 80 feet in the northern part of Castle Valley to 850 feet in the southern part. The Ferron also generally thickens in the subsurface downdip from the outcrop. Records from wells and test holes indicate that the full thickness of the Ferron is saturated with water in most areas downdip from the outcrop area.Tests in the Emery area indicate that transmissivity of the Ferron sandstone aquifer ranges from about 200 to 700 feet squared per day where the Ferron is fully saturated. Aquifer transmissivity is greatest near the Paradise Valley-Joes Valley fault system where permeability has been increased by fracturing. Storage coefficient ranges from about 10 .6 to 10 -3 where the Ferron sandstone aquifer is confined and probably averages 5 x 10-2 where it is unconfined.

  14. Pelletization of fine coals. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Sastry, K.V.S.

    1995-12-31

    Coal is one of the most abundant energy resources in the US with nearly 800 million tons of it being mined annually. Process and environmental demands for low-ash, low-sulfur coals and economic constraints for high productivity are leading the coal industry to use such modern mining methods as longwall mining and such newer coal processing techniques as froth flotation, oil agglomeration, chemical cleaning and synthetic fuel production. All these processes are faced with one common problem area--fine coals. Dealing effectively with these fine coals during handling, storage, transportation, and/or processing continues to be a challenge facing the industry. Agglomeration by the unit operation of pelletization consists of tumbling moist fines in drums or discs. Past experimental work and limited commercial practice have shown that pelletization can alleviate the problems associated with fine coals. However, it was recognized that there exists a serious need for delineating the fundamental principles of fine coal pelletization. Accordingly, a research program has been carried involving four specific topics: (i) experimental investigation of coal pelletization kinetics, (ii) understanding the surface principles of coal pelletization, (iii) modeling of coal pelletization processes, and (iv) simulation of fine coal pelletization circuits. This report summarizes the major findings and provides relevant details of the research effort.

  15. The marriage of gas turbines and coal

    International Nuclear Information System (INIS)

    Bajura, R.A.; Webb, H.A.

    1991-01-01

    This paper reports on developing gas turbine systems that can use coal or a coal-based fuel ensures that the United States will have cost-effective environmentally sound options for supplying future power generation needs. Power generation systems that marry coal or a coal-based fuel to a gas turbine? Some matchmakers would consider this an unlikely marriage. Historically, most gas turbines have been operated only on premium fuels, primarily natural gas or distillate oil. The perceived problems from using coal or coal-based fuels in turbines are: Erosion and deposition: Coal ash particles in the hot combustion gases passing through the expander turbine could erode or deposit on the turbine blades. Corrosion: Coal combustion will release alkali compounds form the coal ash. Alkali in the hot gases passing through the expander turbine can cause corrosion of high-temperature metallic surfaces. Emissions: coal contains higher levels of ash, fuel-bound sulfur and nitrogen compounds, and trace contaminants than premium fuels. Meeting stringent environmental regulations for particulates, sulfur dioxide (SO 2 ), nitrogen oxides (NO x ), and trace contaminants will be difficult. Economics: Coal-based systems are expensive to build. The difference in price between coal and premium fuels must be large enough to justify the higher capital cost

  16. Liquid CO2/Coal Slurry for Feeding Low Rank Coal to Gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Marasigan, Jose [Electric Power Research Institute, Inc., Palo Alto, CA (United States); Goldstein, Harvey [Electric Power Research Institute, Inc., Palo Alto, CA (United States); Dooher, John [Electric Power Research Institute, Inc., Palo Alto, CA (United States)

    2013-09-30

    This study investigates the practicality of using a liquid CO2/coal slurry preparation and feed system for the E-Gas™ gasifier in an integrated gasification combined cycle (IGCC) electric power generation plant configuration. Liquid CO2 has several property differences from water that make it attractive for the coal slurries used in coal gasification-based power plants. First, the viscosity of liquid CO2 is much lower than water. This means it should take less energy to pump liquid CO2 through a pipe compared to water. This also means that a higher solids concentration can be fed to the gasifier, which should decrease the heat requirement needed to vaporize the slurry. Second, the heat of vaporization of liquid CO2 is about 80% lower than water. This means that less heat from the gasification reactions is needed to vaporize the slurry. This should result in less oxygen needed to achieve a given gasifier temperature. And third, the surface tension of liquid CO2 is about 2 orders of magnitude lower than water, which should result in finer atomization of the liquid CO2 slurry, faster reaction times between the oxygen and coal particles, and better carbon conversion at the same gasifier temperature. EPRI and others have recognized the potential that liquid CO2 has in improving the performance of an IGCC plant and have previously conducted systemslevel analyses to evaluate this concept. These past studies have shown that a significant increase in IGCC performance can be achieved with liquid CO2 over water with certain gasifiers. Although these previous analyses had produced some positive results, they were still based on various assumptions for liquid CO2/coal slurry properties.

  17. Interrelating the breakage and composition of mined and drill core coal

    Science.gov (United States)

    Wilson, Terril Edward

    property) indicated that the size distribution and size fraction composition of the drop-shattered/tumbled core more closely resembled the plant feed than the crushed core. An attempt to determine breakage parameters (to allow use of selection and breakage functions and population balance models in the description of bore core size reduction) was initiated. Rank determination of the three coal types was done, indicating that higher rank associates with higher breakage propensity. The two step procedure of drop-shatter and dry batch tumbling simulates the first-order (volume breakage) and zeroth-order (abrasion of particle surfaces) that occur in excavation and handling operations, and is appropriate for drill core reduction prior to laboratory analysis.

  18. Coal preparation

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The acid rain control legislation has prompted the Department of Energy (DOE) to seek new technology using the Clean Coal Technology program solicitation. The main goal of the program is to reduce SO 2 emissions below 9 Mt/a (10 million stpy) and NO x emission below 5.4 Mt/a (6 million stpy) by the year 2000. This would be accomplished by using precombustion, combustion, post combustion and conversion technology. Utilities are considering installing new scrubbers, switching fuel or possibly deep clean. However, the time required to implement the control technology is short. Due to the legislation, about 110 plants will have to adopt one of the approaches. This paper reports that in characterization of coal, Ames Laboratory used a scanning electron microscope- based, automated image analysis (SEM-AIA) technique to identify coal and mineral matter association. Various forms of organic sulfur were identified using peroxyacetic acid oxidation of coal. This was followed by subsequent microscopic, GC-MS, and HRMS analysis by Southern Illinois University. In ultrafine grinding of coal, it was reported by the Mining and Mineral Institute of Alabama that silica sand or flint shot used less energy compared to steel ball mills

  19. Tasks in development of the USSR coal industry

    Energy Technology Data Exchange (ETDEWEB)

    Bratchenko, B F

    1981-08-01

    Minister of the Soviet coal industry evaluates social and economic development plan of the Soviet coal industry from 1981 to 1985. Planned coal production should increase to 770-800 Mt, exceeding coal production in 1980 by 53 to 83 Mt. Proportion of coal mined by surface methods will further increase. Investment program concentrates on: construction of the Kansk-Achinsk fuel and energy basin, construction of the South Yakut coal basin and further development of surface mines in the Ehkibastuz basin. Proportion of coal mined in the Kuzbass will increase to 45% of the total coal output. Construction of the Kansk-Achinsk basin has the highest priority among the investment projects. Investment projects (construction of new coal mines and modernization of existing mines) in major coal basins in 1981 are analyzed. Mining machines and equipment for underground and surface black and brown coal mining are evaluated. Plans for developing new mining systems are described (e.g. narrow web coal cutter with chainless haulage system for thin and medium coal seams with drive system with power ranging from 110 to 315 kW). The following types of machines are discussed: coal cutters, shearer loaders, heading machines, belt conveyors, loaders. Selected social problems associated with manpower shortages for underground mining and for coal mines operating under extreme climatic conditions are also discussed.

  20. Ultra-fast boriding of metal surfaces for improved properties

    Science.gov (United States)

    Timur, Servet; Kartal, Guldem; Eryilmaz, Osman L.; Erdemir, Ali

    2015-02-10

    A method of ultra-fast boriding of a metal surface. The method includes the step of providing a metal component, providing a molten electrolyte having boron components therein, providing an electrochemical boriding system including an induction furnace, operating the induction furnace to establish a high temperature for the molten electrolyte, and boriding the metal surface to achieve a boride layer on the metal surface.