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Sample records for coke dry quenching

  1. Performance of block lining in the zone of slanted ducts of a coke dry quenching unit

    Energy Technology Data Exchange (ETDEWEB)

    Frolova, L.S.; Drozd, V.I.; Zadorozhnaya, T.A.; Minasov, A.N.; Surenskii, O.N.; Ershov, N.A.; Ignashin, G.I.; Mishin, E.N. (UkrNIIO (USSR))

    1991-01-01

    Discusses service life and wear of concrete blocks used for construction of dry coke quenching chambers. Concrete blocks replaced conventional refractory bricks. A filler from calcinated bauxites and a high-alumina cement were used for concrete block production. The blocks were used for construction of the zones of slanted ducts. Concrete block properties are analyzed: dimensions, weight, ultimate compression strength, open porosity, apparent density, linear shrinkage at 1,400 C and holding for 5 hours, content of calcium, aluminium and iron oxides. Abrasive wear and spalling of the working surface of the slanted duct zone made of the concrete blocks was 1.5-2.0 lower than that of conventional refractory bricks in chambers with the same service life. Tests carried out 8 years long showed that the slanted duct zones made of concrete blocks were characterized by higher abrasion resistance and heat resistance, reduced number of joints and increased rigidity of the slanted duct structure. 4 refs.

  2. Joint Implementation Analysis: A Case Study of the Japan-China Coke Dry Quenching (CDQ) Project

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    One of the key issues for "Joint Implementation" is how to define a plausible baseline, a necessary benchmark for calculating net Greenhouse Gases (GHGs) emission reductions through a comparative approach. Based on a thorough case study of the China-Japan Coke Dry Quenching (CDQ) project, the first approved pilot project in China under the "Activities Implemented Jointly" (AIJ) framework, the paper not only describes in detail the complete procedure of baseline definition of the case project, but also discusses its approach to baseline determination. Furthermore, cost-benefit analysis of GHGs mitigation is conducted according to the baseline. This empirical case study, based on real AIJ project data, will be beneficial for the development of future projects under Kyoto mechanisms such as "Clean Development Mechanism" and "Joint Implementation".

  3. Gas Production with Coproduction of Methanol through Dry Quenching of Coke Developed by Yantai Tonqve Chemical/Yantai University

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The Yantai Tongye Chemical Technology Co.,Ltd.and Yantai University have jointly studied and developed the proprietary technology for gas generation through dry quenching of coke with co-production of methanol.Currently this technology has been successfully licensed and the engineering and the design work is underway.

  4. Survey of oven during dry distillation by quenching coke oven. Part 3. ; Consideration concerning density distribution in coke mass. Cokes ro kyurei ni yoru kanryu tochu ronai chosa. Dai sanpo. ; Cokes kainai no mitsudo bunpu ni kansuru ichikosatsu

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, M.; Asada, S.; Kamimura, N. (The Kansai Coke and Chemicals Co. Ltd., Hyogo (Japan))

    1992-06-25

    Recently, in order to probe the coal carbonization mechanism, many companies are carrying out surveys of the inside of an oven by quenching the same which is in dry distillation by employing an actual oven or a test one, and the following are reported; the dry distillating progress are varied at respective positions inside the oven, the portion where dry distillation is greatly delayed is caused by virtue of the action of steam generated from the non-distillated coal layer existing near the coal core rather than the plastic layer, and so forth. The writer and others have already reported that, from the results of the quenching tests carried on actual ovens, the existence of variation of dry distillation, the state of uncarbonized part of coal, the existence of temperature distribution inside coal mass showing that steam was gushing toward the wall of the oven, making it clear that steam generated from the coal layer has great effect on the progress of dry distillation. This paper gives a consideration on the relationship between the pressure exerted on the resetting surface of the plastic substance and the flow of steam inside the oven based on the densness distribution in coal mass. 7refs., 8 figs., 2 tabs.

  5. 干熄焦炉内三维流动及传热的数值模拟%3D numerical simulation of flow and heat transfer in coke dry quenching process

    Institute of Scientific and Technical Information of China (English)

    常庆明; 靳振伟; 程平平; 李亚伟; 董良君

    2014-01-01

    A mathematical model for quenching gas flow and heat transfer between gas and coke in the coke dry quenching (CDQ) unit was established .In the model ,secondary development was done on the platform of Fluent by employing the user defined functions (UDF) and the user defined scalars (UDS) .The calculation results show a bias flow of quenching gas in the chutes ,i .e .more gas flows to the annular gas passage through the chutes near the outlet with relatively larger velocity .The pres-sure loss of the flowing gas mainly takes place in the cooling chamber ,and the heat transfer rate be-tween gas and coke near the side in the chamber is larger than that at the center .Simulation results find that the heated gas temperature can reach about 1101 K at the gas outlet w hile the cooled coke temperature decreases to about 439 K at the coke outlet w hen the circulating air volume is 200 000 m3/h .This can not only meet the cooling requirement of the coke but also supply the recycle gas with high grade heat for further heating or power generation .%以Fluent软件为平台,通过流体在多孔介质中的流动模型来处理冷却气体在干熄焦炉内的三维流动,借助于UDS和UDF进行二次开发,建立干熄焦炉内冷却气体及焦炭的流动传热模型,并分析了循环风量对气固换热的影响。结果表明,冷却室气体在通过斜道进入环形气道时有偏流现象,即靠近总出口附近的斜道有更多的气体流出,且气流速度最快;气体的压力损失主要发生在冷却室;冷却室内周边的换热效果比中心换热效果要好。模拟计算发现,循环风量为200000 m3/h时,换热后的冷却气体温度为1101 K ,焦炭温度为439 K ,这不仅满足了焦炭的冷却要求,而且还能提供用于供暖或发电的高品位热量的循环气体。

  6. Process for removing harmful material after wet quenching in coke oven quenching towers with simultaneous water treatment. Verfahren zur Schadstoffbeseitigung hinter der Nassloeschung in Kokerei-Loeschtuermen bei gleichzeitiger Wasseraufbereitung

    Energy Technology Data Exchange (ETDEWEB)

    Hoelter, H.; Igelbuescher, H.; Gresch, H.; Dewert, H.

    1987-05-27

    In the main patent application P 3538138.8, a process for removing emission from a coke quenching tower is described, where the quenching hood is situated behind the actual quenching tower and the quantities of gas are sprayed with liquids washing out the SO/sub 2/ via condensor arrangements with heat exchangers, where the amounts of gas are restricted to a minimum by condensation and the quantity of gas in clouds of gas is then taken to a dust extractor. In order to improve the process of the main application further, this invention proposes that a dry chemi-sorption technique should be applied after the quenching tower, which is equipped with masses absorbing chemicals and simultaneously absorbing humidity. The chemi-sorption masses taken to the chemi-sorption filter consist of a core material, which is reinforced with means of absorption binding acids to absorb gaseous harmful substances like SO/sub 2/ H/sub 2/S, CN and which also causes the conversion of substances loaded with NO/sub x/.

  7. Design trends of coke oven batteries

    Energy Technology Data Exchange (ETDEWEB)

    Minasov, A.N.; Kononenko, V.S.; Fomenko, V.I. (Giprokoks (USSR))

    1991-01-01

    Analyzes design and operation of 168 coke oven batteries in the USSR with a capacity of 86,507 Mt coke per year. The mean service life of a coke oven battery is 20.9 years. Of 168 batteries 16.1% has a service life below 5 years, 10.7% from 5 to 10, 9.5% from 10 to 15, 9.5% from 15 to 20, 10.1% from 20 to 25. 16.1% from 25 to 30, 10.1% from 30 to 35, 15.5% from 35 to 40 and 2.4% has a service life exceeding 40 years. The following aspects are discussed: dimensions of a coke oven and their effects on coking, types of refractory bricks and elements used for coke oven construction, basic technological solutions and equipment used for reducing environmental pollution (smokeless charging, smokeless coke discharge, dry coke quenching, air pollution control methods), technical refitting of coke oven batteries in the USSR. 4 refs.

  8. Synergetic effects leading to coke-resistant NiCo bimetallic catalysts for dry reforming of methane

    KAUST Repository

    Li, Lidong

    2015-01-08

    A new dry reforming of methane catalyst comprised of NiCo bimetallic nanoparticles and a Mgx(Al)O support that exhibits high coke resistance and long-term on-stream stability is reported. The structural characterization by XRD, TEM, temperature-programmed reduction, and BET analysis demonstrates that the excellent performance of this catalyst is ascribed to the synergy of various parameters, including metal-nanoparticle size, metal-support interaction, catalyst structure, ensemble size, and alloy effects.

  9. High Coke-Resistance Pt/Mg1-xNixO Catalyst for Dry Reforming of Methane.

    Science.gov (United States)

    Al-Doghachi, Faris A J; Islam, Aminul; Zainal, Zulkarnain; Saiman, Mohd Izham; Embong, Zaidi; Taufiq-Yap, Yun Hin

    2016-01-01

    A highly active and stable nano structured Pt/Mg1-xNixO catalysts was developed by a simple co-precipitation method. The obtained Pt/Mg1-xNixO catalyst exhibited cubic structure nanocatalyst with a size of 50-80 nm and realized CH4 and CO2 conversions as high as 98% at 900°C with excellent stability in the dry reforming of methane. The characterization of catalyst was performed using various kinds of analytical techniques including XRD, BET, XRF, TPR-H2, TGA, TEM, FESEM, FT-IR, and XPS analyses. Characterization of spent catalyst further confirms that Pt/Mg1-xNixO catalyst has high coke-resistance for dry reforming. Thus, the catalyst demonstrated in this study, offers a promising catalyst for resolving the dilemma between dispersion and reducibility of supported metal, as well as activity and stability during high temperature reactions.

  10. High Coke-Resistance Pt/Mg1-xNixO Catalyst for Dry Reforming of Methane.

    Directory of Open Access Journals (Sweden)

    Faris A J Al-Doghachi

    Full Text Available A highly active and stable nano structured Pt/Mg1-xNixO catalysts was developed by a simple co-precipitation method. The obtained Pt/Mg1-xNixO catalyst exhibited cubic structure nanocatalyst with a size of 50-80 nm and realized CH4 and CO2 conversions as high as 98% at 900°C with excellent stability in the dry reforming of methane. The characterization of catalyst was performed using various kinds of analytical techniques including XRD, BET, XRF, TPR-H2, TGA, TEM, FESEM, FT-IR, and XPS analyses. Characterization of spent catalyst further confirms that Pt/Mg1-xNixO catalyst has high coke-resistance for dry reforming. Thus, the catalyst demonstrated in this study, offers a promising catalyst for resolving the dilemma between dispersion and reducibility of supported metal, as well as activity and stability during high temperature reactions.

  11. Evaluation method of economic efficiency of industrial scale research based on an example of coking blend pre-drying technology

    Directory of Open Access Journals (Sweden)

    Żarczyński Piotr

    2017-01-01

    Full Text Available The research on new and innovative solutions, technologies and products carried out on an industrial scale is the most reliable method of verifying the validity of their implementation. The results obtained in this research method give almost one hundred percent certainty although, at the same time, the research on an industrial scale requires the expenditure of the highest amount of money. Therefore, this method is not commonly applied in the industrial practices. In the case of the decision to implement new and innovative technologies, it is reasonable to carry out industrial research, both because of the cognitive values and its economic efficiency. Research on an industrial scale may prevent investment failure as well as lead to an improvement of technologies, which is the source of economic efficiency. In this paper, an evaluation model of economic efficiency of the industrial scale research has been presented. This model is based on the discount method and the decision tree model. A practical application of this proposed evaluation model has been presented based on an example of the coal charge pre-drying technology before coke making in a coke oven battery, which may be preceded by industrial scale research on a new type of coal charge dryer.

  12. Carbon dioxide emission in hydrogen production technology from coke oven gas with life cycle approach

    Directory of Open Access Journals (Sweden)

    Burmistrz Piotr

    2016-01-01

    Full Text Available The analysis of Carbon Footprint (CF for technology of hydrogen production from cleaned coke oven gas was performed. On the basis of real data and simulation calculations of the production process of hydrogen from coke gas, emission indicators of carbon dioxide (CF were calculated. These indicators are associated with net production of electricity and thermal energy and direct emission of carbon dioxide throughout a whole product life cycle. Product life cycle includes: coal extraction and its transportation to a coking plant, the process of coking coal, purification and reforming of coke oven gas, carbon capture and storage. The values were related to 1 Mg of coking blend and to 1 Mg of the hydrogen produced. The calculation is based on the configuration of hydrogen production from coke oven gas for coking technology available on a commercial scale that uses a technology of coke dry quenching (CDQ. The calculations were made using ChemCAD v.6.0.2 simulator for a steady state of technological process. The analysis of carbon footprint was conducted in accordance with the Life Cycle Assessment (LCA.

  13. An in-depth understanding of the bimetallic effects and coked carbon species on an active bimetallic Ni(Co)/Al2O3 dry reforming catalyst.

    Science.gov (United States)

    Liao, Xin; Gerdts, Rihards; Parker, Stewart F; Chi, Lina; Zhao, Yongxiang; Hill, Martyn; Guo, Junqiu; Jones, Martin O; Jiang, Zheng

    2016-06-29

    Ni/Al2O3, Co/Al2O3 and bimetallic Ni(Co)/Al2O3 catalysts were prepared using an impregnation method and employed in CO2 dry reforming of methane under coking-favored conditions. The spent catalysts were carefully characterized using typical characterization technologies and inelastic neutron scattering spectroscopy. The bimetallic catalyst exhibited a superior activity and anti-coking performance compared to Ni/Al2O3, while the most resistant to coking behavior was Co/Al2O3. The enhanced activity of the Ni(Co)/Al2O3 bimetallic catalyst is attributed to the reduced particle size of metallic species and resistance to forming stable filamentous carbon. The overall carbon deposition on the spent bimetallic catalyst is comparable to that of the spent Ni/Al2O3 catalyst, whereas the carbon deposited on the bimetallic catalyst is mainly less-stable carbonaceous species as confirmed by SEM, TPO, Raman and INS characterization. This study provides an in depth understanding of alloy effects in catalysts, the chemical nature of coked carbon on spent Ni-based catalysts and, hopefully, inspires the creative design of a new bimetallic catalyst for dry reforming reactions.

  14. Coke- and sintering-resistant monolithic catalysts derived from in situ supported hydrotalcite-like films on Al wires for dry reforming of methane

    Science.gov (United States)

    Du, Xianjun; Zhang, Dengsong; Shi, Liyi; Gao, Ruihua; Zhang, Jianping

    2013-03-01

    Monolithic catalysts derived from in situ supported hydrotalcite-like films on Al wires display high resistance to coke formation and sintering in the dry reforming of methane due to their hierarchical porous structure, well dispersed metallic nickel species, more basic sites and strong metal-support interaction effect.Monolithic catalysts derived from in situ supported hydrotalcite-like films on Al wires display high resistance to coke formation and sintering in the dry reforming of methane due to their hierarchical porous structure, well dispersed metallic nickel species, more basic sites and strong metal-support interaction effect. Electronic supplementary information (ESI) available: Experimental details, XRD patterns, SEM images, and TEM images. See DOI: 10.1039/c3nr33921a

  15. Thermal stress analysis of lining plate for dry quenching%干熄焦衬板的热应力分析

    Institute of Scientific and Technical Information of China (English)

    王厉刚; 李高阳; 滕杰; 马学东

    2012-01-01

    Lining plate of coke dram of dry quenching bears a greater thermal load. It is a damageable part that needs to replace frequently. And prolonging the lining plate life could reduce production cost and improve production efficiency. Thermal stress of the lining plate was analyzed quantificationally by using the finite clement method, and some measures were given to reduce the thermal stress. The work of this thesis provides theoretic foundation for prolonging lining plate life.%干熄焦焦罐衬板承受着较大的热载荷,属于经常更换的易损件,延长衬板的寿命,可以降低生产成本,提高生产效率.采用有限元方法,定量地分析了衬板的热应力,并提出了降低热应力的措施,所作工作为提高衬板寿命提供了理论依据.

  16. Analysis of gas-phase mercury sorption with coke and lignite dust

    Directory of Open Access Journals (Sweden)

    Marczak Marta

    2017-01-01

    Full Text Available In recent years the problem of mercury emission became a widely discussed topic. Its high impact is caused by its toxicity and ability to accumulate in living organisms, properties that justified the United States Environmental Protection Agency (US EPA to classify mercury as hazardous pollutant. The problem of mercury emission is crucial for countries like Poland, where the most of the emission is caused by coaldepended energy sector. Current technology of mercury removal utilizes adsorption of mercury on the surface of activated carbon. Due to high price of activated carbon, this technological approach seems to be uneconomical and calls for cheaper alternative. One possible solution can be usage of other sorptive materials obtained from thermal processes like coke production. Example of such material is coke dust obtained from dry quenching of coke. The aim of this work was to analyse the sorption potential of lignite and coke dust and determine parameters influencing mercury behaviour during combustion.

  17. 降低焦炉机车电器运行重复故障率%Reduce the Repetition Rate of Electric Operation of the Coke Oven Locomotive

    Institute of Scientific and Technical Information of China (English)

    姜玉怀

    2016-01-01

    the coking coal coking company of masteel outdated 1 # 4 # coke oven in order to real-ize the coal charging and coke pushing, blocking water coke dry quenching, quenching, screen coke and dust removal, etc. By the four major locomotive ( coke pusher, coal car, stop coke car, coke quenching car) , due to the special environment of the equipment operation ( mobile, high tempera-ture, dust, stop frequent restart, etc. ) , make the equipment in the process of running frequent fail-ure, not only increase the workload of maintenance, because maintenance delayed production at the same time, reduces the coke oven coke rate, thus the ascension of the whole economic benefit of mas-teel.%马钢煤焦化公司老区焦化1#-4#焦炉为了实现装煤、推焦、拦焦、干熄焦、水熄焦、筛焦、除尘等工艺。由四大机车(推焦车、装煤车、拦焦车、熄焦车)来实现,由于设备运行的特殊环境(移动、高温、多灰尘、停启动频繁等),使得设备在运行过程中故障频发,这不仅仅增加了维修工作量,同时因为检修耽误了生产,降低了焦炉的出焦率,从而影响了整个马钢的经济效益的提升。

  18. Development of Coke-tolerant Transition Metal Catalysts for Dry Reforming of Methane

    KAUST Repository

    Al-Sabban, Bedour E.

    2016-11-07

    Dry reforming of methane (DRM) is an attractive and promising process for the conversion of methane and carbon dioxide which are the most abundant carbon sources into valuable syngas. The produced syngas, which is a mixture of hydrogen and carbon monoxide, can be used as intermediates in the manufacture of numerous chemicals. To achieve high conversion, DRM reaction is operated at high temperatures (700-900 °C) that can cause major drawbacks of catalyst deactivation by carbon deposition, metal sintering or metal oxidation. Therefore, the primary goal is to develop a metal based catalyst for DRM that can completely suppress carbon formation by designing the catalyst composition. The strategy of this work was to synthesize Ni-based catalysts all of which prepared by homogeneous deposition precipitation method (HDP) to produce nanoparticles with narrow size distribution. In addition, control the reactivity of the metal by finely tuning the bimetallic composition and the reaction conditions in terms of reaction temperature and pressure. The highly endothermic dry reforming of methane proceeds via CH4 decomposition to leave surface carbon species, followed by removal of C with CO2-derived species to give CO. Tuning the reactivity of the active metal towards these reactions during DRM allows in principle the catalyst surface to remain active and clean without carbon deposition for a long-term. The initial attempt was to improve the resistance of Ni catalyst towards carbon deposition, therefore, a series of 5 wt.% bimetallic Ni9Pt1 were supported on various metal oxides (Al2O3, CeO2, and ZrO2). The addition of small amount of noble metal improved the stability of the catalyst compared to their monometallic Ni and Pt catalysts, but still high amount of carbon (> 0.1 wt.%) was formed after 24 h of the reaction. The obtained results showed that the catalytic performance, particle size and amount of deposited carbon depends on the nature of support. Among the tested

  19. PROSPECTS FOR COKE BREEZE RECOVERY

    Directory of Open Access Journals (Sweden)

    D. N. Mihnovets

    2012-01-01

    Full Text Available Researches give grounds to believe in the possibility of receiving briquettes from coke waste mixed with peat dry coal and their use for smelting iron in the cupola or as a household fuel.

  20. Automation of a coke battery

    Energy Technology Data Exchange (ETDEWEB)

    Simonov, N.F.; Bannikov, L.S.; Yakushina, E.N.; Mil' ko, M.S.

    1980-10-01

    This paper discusses methods of remote control of machines used for discharging coke ovens. The system, developed by the Construction Office of AiM Giprokoks, consists of a number of detecting and transmitting coupling coils and oscillators installed at various places on a coke battery. A scheme of the automated remote control system is given. Method of placing coupling coils and covering them to prevent damages is explained. Principles of coupling coil operation are described. By means of coupling coils exact position of a quenching car, coke discharging machine, and machine removing the coke oven door, can be controlled. When the position of a machine is not exact, operation of other machines is blocked. Operation of the system is regarded as satisfactory. Principles of operation of another system in which, instead of coupling coils coupling bars are installed, are evaluated. Bars control position of machines. The system has numerous weak points and its introduction is not recommended. (In Russian)

  1. Ni-loaded nanocrystalline ceria-zirconia solid solutions prepared via modified Pechini route as stable to coking catalysts of CH4 dry reforming

    Directory of Open Access Journals (Sweden)

    Sadykov Vladislav A.

    2016-01-01

    Full Text Available Mixed nanocrystalline Ce-Zr-O oxides (Ce/Zr = 1 or 7/3 were prepared by modified Pechini route using ethylene glycol solutions of metal salts. Detailed characterization of their real structure and surface properties by X-ray diffraction on synchrotron radiation with the full-profile Rietveld analysis, high resolution electron microscopy with elemental analysis, Raman spectroscopy, UV-Vis and X-ray photoelectron spectroscopy revealed a high homogeneity of cations distribution in nanodomains resulting in stabilization of disordered cubic phase. This provides a high dispersion of NiO loaded on these mixed oxides by wet impregnation, a high reactivity and mobility of oxygen in these catalysts and strong interaction of Ni with support in the reduced state. This helps to achieve a high activity and coking stability of developed catalysts in CH4 dry reforming in feeds with CH4 concentration up to 15% and CH4/CO2 ratio =1.

  2. Development of a system for wireless stopping of coke oven machines

    Energy Technology Data Exchange (ETDEWEB)

    Mil' ko, M.S.; Yakushina, E.N.; Babanskii, M.I.; Lipskii, M.N. (SKBA NPO Chermetavtomatika (USSR))

    1991-02-01

    Discusses design and operation of a wireless system for control of quenching cars and machines for opening coke oven doors. The system was developed by Chermetavtomatika and tested in the Mariupol' coking plant. It is used on a coke oven battery with a coke oven volume of 41.6 m{sup 3}. The system controls motion of the quenching cars, stopped the cars, controlled door removal after the quenching car reached the proper position. Main system elements are characterized: signal transmitters and receivers, relay systems. The system, recommended for other coking plants, is characterized as accurate and reliable.

  3. High Coke-Resistance Pt/Mg1-xNixO Catalyst for Dry Reforming of Methane: e0145862

    National Research Council Canada - National Science Library

    Faris A J Al-Doghachi; Aminul Islam; Zulkarnain Zainal; Mohd Izham Saiman; Zaidi Embong; Yun Hin Taufiq-Yap

    2016-01-01

    ...°C with excellent stability in the dry reforming of methane. The characterization of catalyst was performed using various kinds of analytical techniques including XRD, BET, XRF, TPR-H2, TGA, TEM, FESEM, FT-IR, and XPS analyses...

  4. High Coke-Resistance Pt/Mg1-xNixO Catalyst for Dry Reforming of Methane

    National Research Council Canada - National Science Library

    Al-Doghachi, Faris A J; Islam, Aminul; Zainal, Zulkarnain; Saiman, Mohd Izham; Embong, Zaidi; Taufiq-Yap, Yun Hin

    2016-01-01

    ...°C with excellent stability in the dry reforming of methane. The characterization of catalyst was performed using various kinds of analytical techniques including XRD, BET, XRF, TPR-H2, TGA, TEM, FESEM, FT-IR, and XPS analyses...

  5. Controlled Surface Segregation Leads to Efficient Coke-Resistant Nickel/Platinum Bimetallic Catalysts for the Dry Reforming of Methane

    Energy Technology Data Exchange (ETDEWEB)

    Li, Lidong [King Abdullah Univ. of Science and Technology, Thuwal (Saudi Arabia); Zhou, Lu [King Abdullah Univ. of Science and Technology, Thuwal (Saudi Arabia); Ould-Chikh, Samy [King Abdullah Univ. of Science and Technology, Thuwal (Saudi Arabia); Anjum, Dalaver H. [King Abdullah Univ. of Science and Technology, Thuwal (Saudi Arabia); Kanoun, Mohammed B. [King Abdullah Univ. of Science and Technology, Thuwal (Saudi Arabia); Scaranto, Jessica [SABIC Corporate Research and Innovation Center, Thuwal (Saudi Arabia); Hedhili, Mohamed N. [King Abdullah Univ. of Science and Technology, Thuwal (Saudi Arabia); Khalid, Syed [Brookhaven National Lab. (BNL), Upton, NY (United States); Laveille, Paco V. [King Abdullah Univ. of Science and Technology, Thuwal (Saudi Arabia); D' Souza, Lawrence [SABIC Corporate Research and Innovation Center, Thuwal (Saudi Arabia); Clo, Alain [King Abdullah Univ. of Science and Technology, Thuwal (Saudi Arabia); Basset, Jean-Marie [King Abdullah Univ. of Science and Technology, Thuwal (Saudi Arabia)

    2015-02-03

    The surface composition and structure are of vital importance for heterogeneous catalysts, especially for bimetallic catalysts, which often vary as a function of reaction conditions (known as surface segregation). The preparation of bimetallic catalysts with controlled metal surface composition and structure is very challenging. In this study, we synthesize a series of Ni/Pt bimetallic catalysts with controlled metal surface composition and structure using a method derived from surface organometallic chemistry. Moreover, the evolution of the surface composition and structure of the obtained bimetallic catalysts under simulated reaction conditions is investigated by various techniques, which include CO-probe IR spectroscopy, high-angle annular dark-field scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy, extended X-ray absorption fine structure analysis, X-ray absorption near-edge structure analysis, XRD, and X-ray photoelectron spectroscopy. It is demonstrated that the structure of the bimetallic catalyst is evolved from Pt monolayer island-modified Ni nanoparticles to core–shell bimetallic nanoparticles composed of a Ni-rich core and a Ni/Pt alloy shell upon thermal treatment. The catalysts are active for the dry reforming of methane, and their catalytic activities, stabilities, and carbon formation vary with their surface composition and structure.

  6. Coke dust enhances coke plant wastewater treatment.

    Science.gov (United States)

    Burmistrz, Piotr; Rozwadowski, Andrzej; Burmistrz, Michał; Karcz, Aleksander

    2014-12-01

    Coke plant wastewater contain many toxic pollutants. Despite physico-chemical and biological treatment this specific type of wastewater has a significant impact on environment and human health. This article presents results of research on industrial adsorptive coke plant wastewater treatment. As a sorbent the coke dust, dozen times less expensive than pulverized activated carbon, was used. Treatment was conducted in three scenarios: adsorptive after full treatment with coke dust at 15 g L(-1), biological treatment enhanced with coke dust at 0.3-0.5 g L(-1) and addition of coke dust at 0.3 g L(-1) prior to the biological treatment. The enhanced biological treatment proved the most effective. It allowed additional removal of 147-178 mg COD kg(-1) of coke dust. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Controlled surface segregation leads to efficient coke-resistant nickel/platinum bimetallic catalysts for the dry reforming of methane

    KAUST Repository

    Li, Lidong

    2015-02-03

    Surface composition and structure are of vital importance for heterogeneous catalysts, especially for bimetallic catalysts, which often vary as a function of reaction conditions (known as surface segregation). The preparation of bimetallic catalysts with controlled metal surface composition and structure is very challenging. In this study, we synthesize a series of Ni/Pt bimetallic catalysts with controlled metal surface composition and structure using a method derived from surface organometallic chemistry. The evolution of the surface composition and structure of the obtained bimetallic catalysts under simulated reaction conditions is investigated by various techniques, which include CO-probe IR spectroscopy, high-angle annular dark-field scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy, extended X-ray absorption fine structure analysis, X-ray absorption near-edge structure analysis, XRD, and X-ray photoelectron spectroscopy. It is demonstrated that the structure of the bimetallic catalyst is evolved from Pt monolayer island-modified Ni nanoparticles to core-shell bimetallic nanoparticles composed of a Ni-rich core and a Ni/Pt alloy shell upon thermal treatment. These catalysts are active for the dry reforming of methane, and their catalytic activities, stabilities, and carbon formation vary with their surface composition and structure. The reform of reforming: A series of alumina-supported Ni/Pt bimetallic nanoparticles (NPs) with controlled surface composition and structure are prepared. Remarkable surface segregation for these bimetallic NPs is observed upon thermal treatment. These bimetallic NPs are active catalysts for CO2 reforming of CH4, and their catalytic activities, stabilities, and carbon formation vary with their surface composition and structure.

  8. Effect of Mineral on Metallurgical Coke Solution Loss Reaction in Blast Furnace

    Institute of Scientific and Technical Information of China (English)

    YANG Jun-he; FENG An-zu; DU He-gui

    2003-01-01

    The catalytic effects of minerals (oxides) on solution loss reaction of coke were investigated in detail by adding oxides to coal which produces coke or absorbing oxides on coke surface. The mineral catalysis index (MCI) which can be used to evaluate catalytic effects of minerals on solution loss of coke comprehensively was proposed. Using the volatility of coal in dry basis and MCI of coal as independent variables to control coke reactivity, the mathematical models of predicting coke reactivity index, coke strength of reactivity were constructed on the basis of the experimental results.

  9. Laboratory studies of briquetting and coking of hard brown coals

    Energy Technology Data Exchange (ETDEWEB)

    Wollenberg, R.; Basanshaw, B.

    1988-01-01

    Assesses feasibility of producing lumpy, high strength coke from hard brown coal unsuitable for conventional briquetting and coking technologies. Laboratory studies used brown coal with 11.5 to 23.5% ash content and 11.8 to 48% coal moisture from the Adun-tschulun, Scharin-gol, Baga-nur and Nalaich deposits in Mongolia. Two experimental briquetting technologies (briquetting of pregranulated coal dust, briquetting of dried coal from slurry comminution) were applied. Resulting briquets were coked at maximum 1,000 C temperature. Graphs provide briquetting and coking results. Influence of major briquetting and coking parameters is evaluated. The highest briquet compression strength obtained ranged between 15.2 and 34.3 MPa, the highest coke compression strength was 32.0 up to 87.0 MPa. Studies proved that suitable coke for use in the metallurgical and chemical industry can be produced from various types of hard brown coal. 6 refs.

  10. RECOVERY AND DESTRUCTIVE TREATMENT OF HARMFUL SUBSTANCE IN COKING PLANT WASTEWATER

    Institute of Scientific and Technical Information of China (English)

    Cheng Jianguang

    2000-01-01

    This paper discussed the comprehensive treatment of coking plant effluent.Cyanide-containing and phenol wastewater was first recovered and utilized respectively, and then, mixed it with other low harmful wastewater for destroying treatment.Treated water was reused in quenching coke.

  11. The identification of dangerously coking coals

    Energy Technology Data Exchange (ETDEWEB)

    Barriocanal, C.; Patrick, J.W.; Walker, P.A. [Loughborough Univ. of Technology, Leicestershire (United Kingdom)] [and others

    1995-12-31

    When coals are carbonised in slot-type ovens, layers of plastic coal are formed parallel to the oven walls and move progressively inwards eventually meeting at the oven centre. It is within these plastic layers that the principal processes which result in particulate coal being converted into porous, fused coke take place. For some coals, usually having volatile matter contents between 17 and 25wt% (dry, ash-free basis), these processes are accompanied by the generation of measurable gas pressures within the plastic layers which attain maximum levels when the two layers meet at the oven centre. These pressures are transmitted through the coke to the oven walls, causing damage if sufficiently high. Other coals, similar in chemical analysis and swelling properties, can be carbonised with impunity. The technical aspects of the coking pressure phenomenon are well known. However, the fundamental processes involved in the generation of internal gas pressures are not fully understood. Thus, before being used in blends for commercial coke production, potentially dangerous coals are tested by carbonising upwards of 180kg charges in moveable-wall ovens and measuring directly the pressures exerted on the walls. Clearly, it would be helpful if dangerously coking coals could be identified from laboratory tests. Preliminary findings of a laboratory study designed to gain further insight into coking pressure development are presented in this paper. Internal gas pressures have been ascribed to volatiles trapped within either the plastic envelope or the plastic layer implying an overlap of the temperature ranges of volatile release and fluidity. An attempts to assess this view using, initially, thermogravimetric analysis and Gieseler plastometry and, later, a coking bomb are described, the results being related to internal gas pressures measured in a 1.5kg double-wall oven.

  12. Homogeneous kinetics and equilibrium predictions of coking propensity in the anode channels of direct oxidation solid-oxide fuel cells using dry natural gas

    Science.gov (United States)

    Walters, Kevin M.; Dean, Anthony M.; Zhu, Huayang; Kee, Robert J.

    Direct electrochemical oxidation (DECO) solid-oxide fuel cells (SOFCs) offer the potential to generate electrical power from hydrocarbon fuels without the need for upstream fuel processing, such as reforming. However, with pure hydrocarbon fuel entering the flow channels at temperatures typically above 700 °C, fuel pyrolysis can cause molecular-weight growth and the formation of deleterious carbonaceous deposits. This paper, which develops a plug-flow model for fuel (natural gas surrogate) within the anode channels, considers the elementary gas-phase chemical kinetics of fuel pyrolysis and oxidation. It also considers the limiting case of local chemical equilibrium. Formation of cyclic hydrocarbon species is used to indicate deposit propensity. Results show that the likelihood of deposit formation depends strongly on cell temperature, current density, and residence time. Generally speaking, equilibrium favors deposit formation early in the channel whereas, owing to limited residence time, the homogeneous finite-rate kinetics predicts relatively low levels of deposit precursors. In the downstream portions, because of electrochemical oxygen flux though the electrode-electrolyte membrane, chemical equilibrium shifts strongly away from deposit formation to volatile carbon-oxygen species. However, the homogeneous finite-rate kinetics predictions show a continuing increase in coking propensity.

  13. The triumphs of coke

    Energy Technology Data Exchange (ETDEWEB)

    Mott, R.A.

    2004-07-01

    This is a reproduction of a booklet specially written by Dr R.A. Mott and designed by Mr G.E. Hall to mark the jubilee of the Coke Oven Managers' Association, founded in 1915. Whilst mentioning early methods of making coke in Great Britain, it deals particularly with the many developments in coke usage which took place before 1915 and is complementary to the 'History of coke making' written by Dr Mott in 1936. Uses covered include: for malting, for non-ferrous metal making, in an iron blast furnace, in crucible steel making, in the chafery and puddling process, in a foundry cupola, and in railway locomotives. 15 ills.

  14. Study and Application of Sealing Material for Coke Oven Chamber

    Institute of Scientific and Technical Information of China (English)

    GAN Feifang; TAI Li

    2005-01-01

    A kind of dry refractory sealing material has been developed to repair the fine cracks in coke oven chamber. With silica sand as the main raw material, the sealing material is blown into coke oven chamber by compressed air while being applied, and bonded to brick surface or filled in fine cracks of chamber under right pressure. The physical properties of the material are similar to those of silica bricks during its application. So it can be adapted to conditions of coke oven and has good service life. The study and application results of the sealing material are described in this paper.

  15. Toward highly efficient in situ dry reforming of H2S contaminated methane in solid oxide fuel cells via incorporating a coke/sulfur resistant bimetallic catalyst layer

    NARCIS (Netherlands)

    Hua, B.; Yan, N.; Li, M.; Sun, Y.-F.; Chen, J.; Zhang, Y.-Q.; Li, J.; Etsell, T.; Sarkar, P.; Luo, J.L.

    2016-01-01

    The escalating global warming effects are a reason for immediate measures to reduce the level of greenhouse gases. In this context, dry reforming of methane (DRM), an old yet both scientifically and industrially important process, is making a comeback in contributing to the utilization of CO2. Howev

  16. Identification and quantification of carbamate pesticides in dried lime tree flowers by means of excitation-emission molecular fluorescence and parallel factor analysis when quenching effect exists.

    Science.gov (United States)

    Rubio, L; Ortiz, M C; Sarabia, L A

    2014-04-11

    A non-separative, fast and inexpensive spectrofluorimetric method based on the second order calibration of excitation-emission fluorescence matrices (EEMs) was proposed for the determination of carbaryl, carbendazim and 1-naphthol in dried lime tree flowers. The trilinearity property of three-way data was used to handle the intrinsic fluorescence of lime flowers and the difference in the fluorescence intensity of each analyte. It also made possible to identify unequivocally each analyte. Trilinearity of the data tensor guarantees the uniqueness of the solution obtained through parallel factor analysis (PARAFAC), so the factors of the decomposition match up with the analytes. In addition, an experimental procedure was proposed to identify, with three-way data, the quenching effect produced by the fluorophores of the lime flowers. This procedure also enabled the selection of the adequate dilution of the lime flowers extract to minimize the quenching effect so the three analytes can be quantified. Finally, the analytes were determined using the standard addition method for a calibration whose standards were chosen with a D-optimal design. The three analytes were unequivocally identified by the correlation between the pure spectra and the PARAFAC excitation and emission spectral loadings. The trueness was established by the accuracy line "calculated concentration versus added concentration" in all cases. Better decision limit values (CCα), in x0=0 with the probability of false positive fixed at 0.05, were obtained for the calibration performed in pure solvent: 2.97 μg L(-1) for 1-naphthol, 3.74 μg L(-1) for carbaryl and 23.25 μg L(-1) for carbendazim. The CCα values for the second calibration carried out in matrix were 1.61, 4.34 and 51.75 μg L(-1) respectively; while the values obtained considering only the pure samples as calibration set were: 2.65, 8.61 and 28.7 μg L(-1), respectively.

  17. A coke preparedness monitoring device

    Energy Technology Data Exchange (ETDEWEB)

    Sazanov, V.F.; Bannikov, L.S.; Chepurnykh, S.F.; Dobromobov, Yu.I.; Pankrat' ev, O.N.; Pinchuk, S.I.; Shifrin, S.I.

    1982-01-01

    A coke preparedness monitoring device for a door extractor contains sounding electrodes, a stabilized voltage source and a meter to record the electrical resistance of the coke. In order to provide monitoring capacity of the preparedness of the coke in the flow and to increase measuring accuracy the device contains sounding electrodes in the coke-treating door extractor; these are connected together with the recorder via an additional stabilized power supply to a stabilized voltage source.

  18. Experience in the adoption of a coke battery with ovens 41. 6 m/sup 3/ in volume

    Energy Technology Data Exchange (ETDEWEB)

    Chemarda, N.A.; Khlebnikov, O.F.; Dobrovinskii, G.B.; Stel' makh, V.A.; Maslova, L.R.; Muzychuk, V.D.

    1982-11-06

    The performance, product quality and design differences of a new, 41.6 m/sup 3/ coking oven battery have been evaluated and compared with those of older smaller units over two years. Improvement in the uniformity of coke bed heating was attained by optimization of combustion air supply and the degree of recirculation of combustion products. Coke produced compares favorably with that from smaller ovens, but has a slightly smaller particle size. Product moisture content is adversely affected by design deficiencies in the wet quenching system. They are being corrected by adoption of a pulsed quenching system and a new irrigation device.

  19. High coking value pitch

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Douglas J.; Chang, Ching-Feng; Lewis, Irwin C.; Lewis, Richard T.

    2014-06-10

    A high coking value pitch prepared from coal tar distillate and has a low softening point and a high carbon value while containing substantially no quinoline insolubles is disclosed. The pitch can be used as an impregnant or binder for producing carbon and graphite articles.

  20. Design and construction of coke battery 1A at Radlin coke plant, Poland

    Energy Technology Data Exchange (ETDEWEB)

    A.M. Kravchenko; D.P. Yarmoshik; V.B. Kamenyuka; G.E. Kos' kova; N.I. Shkol' naya; V.V. Derevich; A.S. Grankin [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

    2009-07-15

    In the design and construction of coke battery 1A at Radlin coke plant (Poland), coking of rammed coke with a stationary system was employed for the first time. The coke batteries are grouped in blocks. Safety railings are provided on the coke and machine sides of the maintenance areas.

  1. Coke: its constitution and utilisation

    Energy Technology Data Exchange (ETDEWEB)

    Ruth Callcott; Tom Callcott [Callcott Consulting (Australia)

    2008-06-15

    Coke made in coke ovens from coal and used in iron blast furnaces is a strategically critical manufactured product for contemporary and future world iron production. The important physical, chemical and microscopic properties of cokes are examined and explained, drawing on both an exhaustive literature review and the extensive R&D, consulting and industrial experience of the authors. The emphasis is on characterising the family of cokes as materials rather than considering the raw materials of carbonisation and the carbonisation processes. The term 'coke' covers a wide range of materials that can be classified in a number of ways based either on properties or utilisation practices. With few exceptions, these materials are manufactured for specific industrial purposes such as metallurgical processes, making gases or filtering fluids. This report primarily concerns industrial cokes with special concern for blast furnace cokes and their utilisation in iron making. Other industrial cokes and those made in pilot plants or laboratory ovens receive attention where their properties help understand primary utilisation as blast furnace coke.

  2. Health-hazard evaluation report HETA 85-441-1765, New Boston Coke Corporation, New Boston, Ohio

    Energy Technology Data Exchange (ETDEWEB)

    O' Malley, M.A.

    1986-12-01

    In response to a request from the Industrial Commission of Ohio, worker complaints of skin disease at the New Boston Coke Corporation, New Boston, Ohio were investigated. The request was based on seven reports of dermatitis thought to be associated with steam exposure during coke quenching. Quench water had a pH of 8.85 and contained phenol, ammonia, calcium-oxide, and suspended particulates (82% organic compounds); no irritant threshold levels were found for these compounds. Skin tests in rabbits showed a minimal irritant capacity for quench water. Medical records did not reveal the origin of dermatitis. Active skin lesions were characterized as nummular eczema or atopic dermatitis, which were not thought to be of occupational origin. The author concludes that coke-quenching steam does not pose a skin hazard, but certain work activities may aggravate existing skin conditions. Recommendations include elimination of abrasive cleansing agents, use of skin moisturizers after washing, and prompt medical evaluation of skin complaints.

  3. South Africa faces coke shortage

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-05-01

    Iscor Vanderbijlpark in South Africa may need to import substantial tonnages of coking coal as a result of increasing quality demands on coke at Vanderbiljpark (to support the recently installed PCI process) as well as the Newcastle works. Availability of coke is not only a problem for the South African steel industry but is a global problem as the production of coke in Western countries has declined over the past three years. A massive expansion in coke-making capacity is happening in China but the Chinese beehive ovens create serious pollution problems. A world shortage of coke of 30 million t/y by 2005 is estimated, rising to over 60 million t/y by 2010 of no new capacity is created. Steelmakers have succeeded in reducing their consumption of coke, by pulverised coal injection by better distribution of components in the furnace shaft and by decline in use of the blast furnace-basic oxygen furnace route, but the industry is still facing serious shortages of coke.

  4. Design of 7 m coke scraping device%7m扒焦机的设计

    Institute of Scientific and Technical Information of China (English)

    乔海洋; 杜芳蕊; 刘万刚

    2015-01-01

    介绍了一种7m扒焦机,主要由车体、扒焦装置和熄焦输送装置等组成,具有结构简单、模块化拆装和造价低廉等特点,能够安全高效地解决焦炉难推焦问题。%This paper introduces a 7m coke scraping device,which is mainly composed of steel struc-ture platform,coke scraping unit and coke quenching&conveying unit. It has the advantages of sim-ply structure,module assembly & disassembly and low cost,and it could safely and efficiently solve the problem of hard pushing in coke oven battery.

  5. Coking technology using packed coal mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Kuznichenko, V.M.; Shteinberg, Eh.A.; Tolstoi, A.P. (Khar' kovskii Nauchno-Issledovatel' skii Uglekhimicheskii Institut, Kharkov (Ukrainian SSR))

    1991-08-01

    Discusses coking of packed coal charges in the FRG, USSR, France, India, Poland and Czechoslovakia. The following aspects are evaluated: types of weakly caking coals that are used as components of packed mixtures, energy consumption of packing, effects of coal mixture packing on coke oven design, number of coke ovens in a battery, heating temperature, coking time, coke properties, investment and operating cost. Statistical data that characterize the Saarberg packing process used in the FRG are analyzed. Packing coal mixtures for coking improves coke quality and reduces environmental pollution. 4 refs.

  6. PROBLEMS WITH DETERMINATION OF FUGITIVE EMISSION OF POLYCYCLIC AROMATIC HYDROCARBONS FROM COKE OVEN BATTERY

    Directory of Open Access Journals (Sweden)

    Rafał Bigda

    2017-03-01

    Full Text Available Coke oven battery is complex and multifaceted facility in terms of air pollutant emissions. As far as stack or quenching tower does not cause major difficulties of emission measurement, the fugitive emission measurement from sources such as battery top elements (charging holes, ascension pipes or oven doors is still complicated and not fully solved problem. This article presents the discussion concerning main problems and errors likely to be made in particular stages of procedure of fugitive emissions characterization from coke oven battery (selection of sampling points, sampling itself, measurement of air velocity over battery top and laboratory analyses. In addition, results of concentrations measurements of selected substances characteristic for the coking process (naphthalene, anthracene, 4 PAHs and TSP originating from fugitive sources of coke oven battery and subjected to reporting under the E-PRTR are presented. The measurements were carried out on coke oven battery top in points selected on the basis of the preceding detailed air convection velocity measurements over battery top. Results of the velocity measurements were compared with results of numerical modelling using CFD software. The presented material is an attempt to cross-sectional presentation of issues related to the quantitative evaluation of fugitive emission from coke oven battery, discussed on the example of PAHs emission as a group of substances characteristic for coking of coal.

  7. Health Effects of Petroleum Coke

    Science.gov (United States)

    Significant quantities of fugitive dust from pet coke storage and handling operations present a health risk. EPA’s research suggests that petcoke does not pose a different health risk than similar-sized particulate matter (PM10).

  8. Assessment of coke oven emissions exposure among coking workers

    Energy Technology Data Exchange (ETDEWEB)

    Chen, M.L.; Mao, I.F.; Wu, M.T.; Chen, J.R.; Ho, C.K.; Smith, T.J.; Wypij, D.; Christiani, D.C. [National Yang Ming University, Taipei (Taiwan). Dept. of Public Health

    1999-01-01

    Coking workers are regularly exposed to coke oven emissions, which consist primarily of polycyclic aromatic hydrocarbons and volatile organic compounds. This study measured the workers` exposure to the benzene soluble fraction of total particulates (BSF). Personal breathing-zone samples of BSF and total particulates were taken from all study subjects for 3 consecutive days. The highest BSF concentrations were found among the topside oven workers. Among the samples at the topside oven 84% exceeded the Occupational Safety and Health Administration standard (150 {mu}g/m{sup 3} BSF). The percentage of BSF in total particulates varied across job classifications, ranging from 0.3% in wharf men to 24% in tar chasers. Area sampling indicated that the BSF concentration at the topside area was sixty fold higher than that at the administrative area, which was approximately 2 km from the coke oven plant.

  9. 46 CFR 148.04-15 - Petroleum coke, uncalcined; petroleum coke, uncalcined and calcined (mixture).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Petroleum coke, uncalcined; petroleum coke, uncalcined and calcined (mixture). 148.04-15 Section 148.04-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND... Requirements for Certain Material § 148.04-15 Petroleum coke, uncalcined; petroleum coke, uncalcined and...

  10. Trends in the automation of coke production

    Energy Technology Data Exchange (ETDEWEB)

    R.I. Rudyka; Y.E. Zingerman; K.G. Lavrov [Giprokoks, the State Institute for the Design of Coke-Industry Enterprises, Kharkov (Ukraine)

    2009-07-15

    Up-to-date mathematical methods, such as correlation analysis and expert systems, are employed in creating a model of the coking process. Automatic coking-control systems developed by Giprokoks rule out human error. At an existing coke battery, after introducing automatic control, the heating-gas consumption is reduced by {>=}5%.

  11. 77 FR 32998 - Foundry Coke From China

    Science.gov (United States)

    2012-06-04

    ... COMMISSION Foundry Coke From China Determination On the basis of the record \\1\\ developed in the subject five... order on foundry coke from China would be likely to lead to continuation or recurrence of material... Commission are contained in USITC Publication 4326 (May 2012), entitled Foundry Coke from...

  12. Effect of mechanochemical treatment on petroleum coke-CO{sub 2} gasification

    Energy Technology Data Exchange (ETDEWEB)

    Jianhui Zou; Boli Yang; Kaifeng Gong; Shiyong Wu; Zhijie Zhou; Fuchen Wang; Zunhong Yu [East China University of Science and Technology, Shanghai (China). Key Laboratory of Coal Gasification of Ministry of Education

    2008-05-15

    The effect of mechanochemical treatment during the grinding of petroleum coke on its gasification by CO{sub 2} was studied. An additive derived by drying the black liquor in papermaking industry is adopted in grinding process. Results show that the gasification reactivity of petroleum coke is effectively improved by grinding, and the activation by wet grinding is more noticeable than that by dry grinding. Besides, by wet grinding petroleum coke and additive together, the active metal species in additive are not easily volatilized in gasification, and retain a high catalytic reactivity to the coke-CO{sub 2} reaction throughout most of the conversion range. Changes in crystal structure of the petroleum coke induced by mechanochemical treatment is related to its gasification reactivity. In general, the crystalline-amorphous phase transition is the tendency of long time mechanical grinding, while a crystal structure re-formation stage is observed after wet grinding of petroleum coke with and without additive for some time. Similar phenomenon has also been found in the reported data, but not given attention. Some discussion is made in the paper, and more work should be undertaken to disclose the mechanism. 28 refs., 4 figs., 1 tab.

  13. Bio-coke as an alternative to petroleum coke and metallurgical coke; Bio-cokes als alternatief voor petroleumcokes en metallurgische cokes

    Energy Technology Data Exchange (ETDEWEB)

    Croezen, H.J.; Van Lieshout, M. [CE Delft, Delft (Netherlands); Sevenster, M.N. [Sevenster Environmental Consultancy, Australian Capital Territory ACT (Australia)

    2012-11-15

    In the framework of elaborating the Dutch Roadmap Chemistry 2030), CE Delft has conducted an exploratory study for the Association of the Dutch Chemical Industry (VNCI) on the options of replacing (petroleum) coke in the chemical sector by biocokes. Coke is used as a reducing agent and/or raw material in four companies in the Dutch chemical industry (Tronox, ESD-SIC, Thermphos, Aluchemie). Replacing coke at these four companies can potentially yield a direct CO2 reduction of expectedly several hundreds of kilotons per year. For a first exploration of the options of bio-coke, CE Delft first conducted a desk study to get information on the quality and production costs for bio-coke. Subsequently, CE Delft had contact with the four chemical companies and a made a number of company visits. Moreover, the technical, economic and organizational capabilities, constraints and requirements with regard to a possible (partial) switch to biocokes have been explored. Based on the information available so far it can be concluded that biocokes seems to be a technically and economically interesting innovation. For implementation to finally take place, it is necessary to gain better insight in the technical and economic potential [Dutch] In verband met de uitwerking van de Routekaart Chemie 2030 heeft CE Delft voor VNCI een verkenning uitgevoerd naar de mogelijkheden voor vervanging van (petroleum)cokes in de chemische sector door biocokes. Cokes wordt gebruikt als reductiemiddel en/of grondstof bij een viertal bedrijven in de Nederlandse chemie (Tronox, ESD-SIC, Thermphos, Aluchemie). Het vervangen van cokes bij deze vier bedrijven kan in potentie een directe CO2-reductie van naar verwachting enkele honderden kilotonnen/jaar opleveren. Voor een eerste verkenning van de mogelijkheden van bio-cokes heeft CE Delft eerst een bureaustudie uitgevoerd naar informatie over kwaliteit van en productiekosten voor bio-cokes. Vervolgens heeft CE Delft contact gehad met de vier chemische

  14. Fissure formation in coke. 2: Effect of heating rate, shrinkage and coke strength

    Energy Technology Data Exchange (ETDEWEB)

    D.R. Jenkins; M.R. Mahoney [CSIRO, North Ryde, NSW (Australia). Mathematical and Information Sciences

    2010-07-15

    We investigate the effects of the heating rate, coke shrinkage and coke breakage strength upon the fissure pattern developed in a coke oven charge during carbonisation. This is done principally using a mechanistic model of the formation of fissures, which considers them to be an array of equally spaced fissures, whose depth follows a 'period doubling' pattern based upon the time history of the fissures. The model results are compared with pilot scale coke oven experiments. The results show that the effect of heating rate on the fissure pattern is different to the effect of coke shrinkage, while the effect of coke breakage strength on the pattern is less pronounced. The results can be seen in both the shape and size of resulting coke lumps after stabilisation. The approach gives the opportunity to consider means of controlling the carbonisation process in order to tune the size of the coke lumps produced. 7 refs., 18 figs., 4 tabs.

  15. Comparison of metallurgical coke and lignite coke for power generation in Thailand

    Science.gov (United States)

    Ratanakuakangwan, Sudlop; Tangjitsitcharoen, Somkiat

    2017-04-01

    This paper presents and compares two alternatives of cokes in power generation which are the metallurgical coke with coke oven gas and the coke from lignite under the consideration of the energy and the environment. These alternatives not only consume less fuel due to their higher heat content than conventional coal but also has less SO2 emission. The metallurgical coke and its by-product which is coke oven gas can be obtained from the carbonization process of coking coal. According to high grade coking coal, the result in the energy attitude is not profitable but its sulfur content that directly affects the emission of SO2 is considered to be very low. On the other hand, the coke produced from lignite is known as it is the lowest grade from coal and it causes the high pollution. Regarding to energy profitability, the lignite coke is considered to be much more beneficial than the metallurgical coke in contrast to the environmental concerns. However, the metallurgical coke has the highest heating value. Therefore, a decision making between those choices must be referred to the surrounding circumstances based on energy and environment as well as economic consideration in the further research.

  16. Investigation on activated semi-coke desulfurization

    Institute of Scientific and Technical Information of China (English)

    SHANGGUAN Ju; LI Zhuan-li; LI Chun-hu

    2005-01-01

    An activated semi-coke with industrial-scale size was prepared by high-pressure hydrothermal chemistry activation, HNO3oxidation and calcination activation in proper order from Inner Mongolia Zhalainuoer semi-coke, which is rich in resource and cheap in sale.SO2 adsorption capacity on this activated semi-coke was assessed in the fixed bed in the temperature range of 60-170℃, space velocity range of 500-1300 h-1, SO2 concentration of 1000-3000 ppmv, and N2 as balance. The surface area, elemental and proximate analysis for both raw semi-coke and activated semi-cokes were measured. The experimental results showed that the activated semi-coke has a high adsorption capacity for sulfur dioxide than the untreated semi-coke. This may be the result of increase of surface area on activated semi-coke and surface oxygen functional groups with basicity characteristics. Comparison to result of FTIR, it is known that group of-C-O-C- may be active center of SO2 catalytic adsorption on activated semi-coke.

  17. Briquetting of Coke-Brown Coal Mixture

    Directory of Open Access Journals (Sweden)

    Ïurove Juraj

    1998-09-01

    Full Text Available The paper presents the results of the research of briquetting a coke-brown coal composite The operation consists of the feeding crushed coal and coke to moulds and pressing into briquettes which have been made in the Laboratories at the Mining Faculty of Technical University of Košice (Slovakia. In this research, all demands will be analyzed including the different aspects of the mechanical quality of briquettes, the proportion of fine pulverulent coal and coke in bricks, the requirements for briquetting the coke-brown coal materials.

  18. Derivation of heat value of coke/char from proximate analysis

    Energy Technology Data Exchange (ETDEWEB)

    Roy, R.R.P. (and others)

    From experimental data on high-, medium- and low-temperature cokes or chars, the following formulae were derived: gross CV (kcal/kg) 80(FC) + 76(VM); hydrogen content 0.224(VM). All values are on the air-dried basis.

  19. The coke drum thermal kinetic effects

    Energy Technology Data Exchange (ETDEWEB)

    Aldescu, Maria M.; Romero, Sim; Larson, Mel [KBC Advanced Technologies plc, Surrey (United Kingdom)

    2012-07-01

    The coke drum thermal kinetic dynamics fundamentally affect the coker unit yields as well as the coke product properties and unit reliability. In the drum the thermal cracking and polymerization or condensation reactions take place in a semi-batch environment. Understanding the fundamentals of the foaming kinetics that occur in the coke drums is key to avoiding a foam-over that could result in a unit shutdown for several months. Although the most dynamic changes with time occur during drum filling, other dynamics of the coker process will be discussed as well. KBC has contributed towards uncovering and modelling the complexities of heavy oil thermal dynamics. (author)

  20. Technical Progress of China's Delayed Coking Technology

    Institute of Scientific and Technical Information of China (English)

    Zhang Lixin; Li Hejie

    2005-01-01

    This article introduces the recent advances of China in the fields of process technology of delayed coking, enlarged equipment size, hydraulic decoking, automatic control and environmental protection. By the end of 2004 the total capacity of delayed coking units in China had reached 37.24Mt/a with the maximum coke drum diameter equating to 9.4 m. This article also presents the investment in delayed cokers and the current production status while pointing out the existing problems and future development trends.

  1. Preliminary Study of Thermal Treatment of Coke Wastewater Sludge Using Plasma Torch

    Science.gov (United States)

    Li, Mingshu; Li, Shengli; Sun, Demao; Liu, Xin; Feng, Qiubao

    2016-10-01

    Thermal plasma was applied for the treatment of coke wastewater sludge derived from the steel industry in order to investigate the feasibility of the safe treatment and energy recovery of the sludge. A 30 kW plasma torch system was applied to study the vitrification and gas production of coke wastewater sludge. Toxicity leaching results indicated that the sludge treated via the thermal plasma process converted into a vitrified slag which resisted the leaching of heavy metals. CO2 was utilized as working gas to study the production and heat energy of the syngas. The heating value of the gas products by thermal plasma achieved 8.43 kJ/L, indicating the further utilization of the gas products. Considering the utilization of the syngas and recovery heat from the gas products, the estimated treatment cost of coke wastewater sludge via plasma torch was about 0.98 CNY/kg sludge in the experiment. By preliminary economic analysis, the dehydration cost takes an important part of the total sludge treatment cost. The treatment cost of the coke wastewater sludge with 50 wt.% moisture was calculated to be about 1.45 CNY/kg sludge dry basis. The treatment cost of the coke wastewater sludge could be effectively controlled by decreasing the water content of the sludge. These findings suggest that an economic dewatering pretreatment method could be combined to cut the total treatment cost in an actual treatment process.

  2. Fundamentals of Delayed Coking Joint Industry Project

    Energy Technology Data Exchange (ETDEWEB)

    Michael Volk; Keith Wisecarver

    2004-09-26

    Delayed coking evolved steadily over the early to mid 1900s to enable refiners to convert high boiling, residual petroleum fractions to light products such as gasoline. Pound for pound, coking is the most energy intensive of any operation in a modern refinery. Large amounts of energy are required to heat the thick, poor-quality petroleum residuum to the 900 to 950 degrees F required to crack the heavy hydrocarbon molecules into lighter, more valuable products. One common misconception of delayed coking is that the product coke is a disadvantage. Although coke is a low valued (near zero economic value) byproduct, compared to transportation fuels, there is a significant worldwide trade and demand for coke as it is an economical fuel. Coke production has increased steadily over the last ten years, with further increases forecast for the foreseeable future. Current domestic production is near 111,000 tons per day. A major driving force behind this increase is the steady decline in crude quality available to refiners. Crude slates are expected to grow heavier with higher sulfur contents while environmental restrictions are expected to significantly reduce the demand for high-sulfur residual fuel oil. Light sweet crudes will continue to be available and in even greater demand than they are today. Refiners will be faced with the choice of purchasing light sweet crudes at a premium price, or adding bottom of the barrel upgrading capability, through additional new investments, to reduce the production of high-sulfur residual fuel oil and increase the production of low-sulfur distillate fuels. A second disadvantage is that liquid products from cokers frequently are unstable, i.e., they rapidly form gum and sediments. Because of intermediate investment and operating costs, delayed coking has increased in popularity among refiners worldwide. Based on the 2000 Worldwide Refining Survey published in the Oil and Gas, the delayed coking capacity for 101 refineries around the world

  3. Fundamentals of Delayed Coking Joint Industry Project

    Energy Technology Data Exchange (ETDEWEB)

    Michael Volk; Keith Wisecarver

    2003-09-26

    Delayed coking evolved steadily over the early to mid 1900s to enable refiners to convert high boiling, residual petroleum fractions to light products such as gasoline. Pound for pound, coking is the most energy intensive of any operation in a modern refinery. Large amounts of energy are required to heat the thick, poor-quality petroleum residuum to the 900 to 950 degrees F required to crack the heavy hydrocarbon molecules into lighter, more valuable products. One common misconception of delayed coking is that the product coke is a disadvantage. Although coke is a low valued (near zero economic value) byproduct, compared to transportation fuels, there is a significant worldwide trade and demand for coke as it is an economical fuel. Coke production has increased steadily over the last ten years, with further increases forecast for the foreseeable future. Current domestic production is near 111,000 tons per day. A major driving force behind this increase is the steady decline in crude quality available to refiners. Crude slates are expected to grow heavier with higher sulfur contents while environmental restrictions are expected to significantly reduce the demand for high-sulfur residual fuel oil. Light sweet crudes will continue to be available and in even greater demand than they are today. Refiners will be faced with the choice of purchasing light sweet crudes at a premium price, or adding bottom of the barrel upgrading capability, through additional new investments, to reduce the production of high-sulfur residual fuel oil and increase the production of low-sulfur distillate fuels. A second disadvantage is that liquid products from cokers frequently are unstable, i.e., they rapidly form gum and sediments. Because of intermediate investment and operating costs, delayed coking has increased in popularity among refiners worldwide. Based on the 2000 Worldwide Refining Survey published in the Oil and Gas, the delayed coking capacity for 101 refineries around the world

  4. TASK 2: QUENCH ZONE SIMULATION

    Energy Technology Data Exchange (ETDEWEB)

    Fusselman, Steve

    2015-09-30

    Aerojet Rocketdyne (AR) has developed an innovative gasifier concept incorporating advanced technologies in ultra-dense phase dry feed system, rapid mix injector, and advanced component cooling to significantly improve gasifier performance, life, and cost compared to commercially available state-of-the-art systems. A key feature of the AR gasifier design is the transition from the gasifier outlet into the quench zone, where the raw syngas is cooled to ~ 400°C by injection and vaporization of atomized water. Earlier pilot plant testing revealed a propensity for the original gasifier outlet design to accumulate slag in the outlet, leading to erratic syngas flow from the outlet. Subsequent design modifications successfully resolved this issue in the pilot plant gasifier. In order to gain greater insight into the physical phenomena occurring within this zone, AR developed a cold flow simulation apparatus with Coanda Research & Development with a high degree of similitude to hot fire conditions with the pilot scale gasifier design, and capable of accommodating a scaled-down quench zone for a demonstration-scale gasifier. The objective of this task was to validate similitude of the cold flow simulation model by comparison of pilot-scale outlet design performance, and to assess demonstration scale gasifier design feasibility from testing of a scaled-down outlet design. Test results did exhibit a strong correspondence with the two pilot scale outlet designs, indicating credible similitude for the cold flow simulation device. Testing of the scaled-down outlet revealed important considerations in the design and operation of the demonstration scale gasifier, in particular pertaining to the relative momentum between the downcoming raw syngas and the sprayed quench water and associated impacts on flow patterns within the quench zone. This report describes key findings from the test program, including assessment of pilot plant configuration simulations relative to actual

  5. NUMERICAL SIMULATION FOR A PROCESS ANALYSIS OF A COKE OVEN

    Institute of Scientific and Technical Information of China (English)

    Zhancheng Guo; Huiqing Tang

    2005-01-01

    A computational fluid dynamic model is established for a coking process analysis of a coke oven using PHOENICS CFD package. The model simultaneously calculates the transient composition, temperatures of the gas and the solid phases, velocity of the gas phase and porosity and density of the semi-coke phase. Numerical simulation is illustrated in predicting the evolution of volatile gases, gas flow paths, profiles of density, porosity of the coke oven charge,profiles of temperatures of the coke oven gas and the semi-coke bed. On the basis of above modeling, the flow of coke oven gas (COG) blown from the bottom of the coke oven into the porous semi-coke bed is simulated to reveal whether or not and when the blown COG can uniformly flow through the porous semi-coke bed for the purpose of desulfurizing the semi-coke by recycling the COG. The simulation results show that the blown COG can uniformly flow through the semi-coke bed only after the temperature at the center of the semi-coke bed has risen to above 900 ℃.

  6. Effects of thermal quenching on the breakup of pyroclasts

    Science.gov (United States)

    Patel, A.; Manga, M.; Carey, R. J.; Degruyter, W.; Dufek, J.

    2012-12-01

    It is often assumed that magma fragments when it contacts water. Obsidian chips and glass spheres crack when quenched. Vesicular pyroclasts are made of similar glass, so thermal quenching may cause them to break more easily. We performed a set of experiments on air fall pumice from Medicine Lake, California. Density and texture of similar samples are described in Manga et al., Bull Volc 2010. We made "quenched" samples by heating natural pyroclasts to 600 °C, quenching them in water at 21 °C, drying them at 105 °C, and then cooling them to room temperature. We compare these samples with untreated air fall pumice from the same deposit, hereafter referred to as "regular" pumice. We tested whether quenched pumice would 1) shatter more easily in collisions and 2) abrade faster. Our collision experiment methods are described in Dufek et al., Nature Geoscience 2012. Our abrasion experiment methods are described in Manga et al., Bull Volc 2010. We also tested whether individual clasts lose mass upon quenching and whether they increase in effective wet density. Effective wet density is defined as underwater density of a clast when water occupies part of the pore space. Effective wet density, measured as a function of time after immersion, indicates the volume fraction of the pore space that becomes occupied by water. We compare effective wet density of individual clasts pre-quenching with effective wet density after having been quenched, thoroughly dried and then cooled to room temperature. An increase in effective wet density would suggest that bubble walls had been damaged during quenching, allowing water to occupy the pore space faster. We also compare pre-quenching and post-quenching textures using X-Ray Tomography (XRT) and SEM images. Results from collision experiments show no obvious difference between quenched pumice and regular pumice. Quenched pumice abraded more quickly than regular pumice. We find that 1 to 2 % of mass was lost during quenching. Effective

  7. Coke fouling monitoring by electrical resistivity

    Energy Technology Data Exchange (ETDEWEB)

    Bombardelli, Clovis; Mari, Livia Assis; Kalinowski, Hypolito Jose [Universidade Tecnologica Federal do Parana (UTFPR), Curitiba, PR (Brazil). Programa de Pos-Graduacao em Engenharia Eletrica e Informatica Industrial (CPGEI)

    2008-07-01

    An experimental method to simulate the growth of the coke fouling that occurs in the oil processing is proposed relating the thickness of the encrusted coke to its electrical resistivity. The authors suggest the use of the fouling electrical resistivity as a transducer element for determining its thickness. The sensor is basically two electrodes in an electrically isolated device where the inlay can happen in order to compose a purely resistive transducer. Such devices can be easily constructed in a simple and robust form with features capable to face the high temperatures and pressures found in relevant industrial processes. For validation, however, it is needed a relationship between the electrical resistivity and the fouling thickness, information not yet found in the literature. The present work experimentally simulates the growth of a layer of coke on an electrically insulating surface, equipped with electrodes at two extremities to measure the electrical resistivity during thermal cracking essays. The method is realized with a series of consecutive runs. The results correlate the mass of coke deposited and its electrical resistivity, and it can be used to validate the coke depositions monitoring employing the resistivity as a control parameter. (author)

  8. Gasification Reaction Characteristics of Ferro-Coke at Elevated Temperatures

    Science.gov (United States)

    Wang, Peng; Zhang, Jian-liang; Gao, Bing

    2017-01-01

    In this paper, the effects of temperature and atmosphere on the gasification reaction of ferro-coke were investigated in consideration of the actual blast furnace conditions. Besides, the microstructure of the cokes was observed by scanning electron microscope (SEM). It is found that the weight loss of ferro-coke during the gasification reaction is significantly enhanced in the case of increasing either the reaction temperature or the CO2 concentration. Furthermore, compared with the normal type of metallurgical coke, ferro-coke exhibits a higher weight loss when they are gasified at the same temperature or under the same atmosphere. As to the microstructure, inside the reacted ferro-coke are a large amount of pores. Contrary to the normal coke, the proportions of the large-size pores and the through holes are greatly increased after gasification, giving rise to thinner pore walls and hence a degradation in coke strength after reaction (CSR).

  9. The control of volume flow heating gases oh coke plant

    Directory of Open Access Journals (Sweden)

    Kostúr Karol

    2003-12-01

    Full Text Available The contribution deals with mixture and coke gases volume quantity determination for coke battery in term of their optimal redistribution at single blocks in consideration of accurate observance of corresponding technological temperature.

  10. Fissure formation in coke. 3: Coke size distribution and statistical analysis

    Energy Technology Data Exchange (ETDEWEB)

    D.R. Jenkins; D.E. Shaw; M.R. Mahoney [CSIRO, North Ryde, NSW (Australia). Mathematical and Information Sciences

    2010-07-15

    A model of coke stabilization, based on a fundamental model of fissuring during carbonisation is used to demonstrate the applicability of the fissuring model to actual coke size distributions. The results indicate that the degree of stabilization is important in determining the size distribution. A modified form of the Weibull distribution is shown to provide a better representation of the whole coke size distribution compared to the Rosin-Rammler distribution, which is generally only fitted to the lump coke. A statistical analysis of a large number of experiments in a pilot scale coke oven shows reasonably good prediction of the coke mean size, based on parameters related to blend rank, amount of low rank coal, fluidity and ash. However, the prediction of measures of the spread of the size distribution is more problematic. The fissuring model, the size distribution representation and the statistical analysis together provide a comprehensive capability for understanding and predicting the mean size and distribution of coke lumps produced during carbonisation. 12 refs., 16 figs., 4 tabs.

  11. Fundamentals of Delayed Coking Joint Industry Project

    Energy Technology Data Exchange (ETDEWEB)

    Volk Jr., Michael; Wisecarver, Keith D.; Sheppard, Charles M.

    2003-02-07

    The coking test facilities include three reactors (or cokers) and ten utilities. Experiments were conducted using the micro-coker, pilot-coker, and stirred-batch coker. Gas products were analyzed using an on-line gas chromatograph. Liquid properties were analyzed in-house using simulated distillation (HP 5880a), high temperature gas chromatography (6890a), detailed hydrocarbon analysis, and ASTM fractionation. Coke analyses as well as feedstock analyses and some additional liquid analyses (including elemental analyses) were done off-site.

  12. Shift from coke to coal using direct reduction method and challenges

    Energy Technology Data Exchange (ETDEWEB)

    Okonkwo Paul Chukwuleke; Jiu-ju Cai; Sam Chukwujekwu; Song Xiao [Deakin University, Waurn Ponds, Vic. (Australia)

    2009-03-15

    Ironmaking involves the separation of iron ores. It not only represents the first step in steelmaking but also is the most capital-intensive and energy-intensive process in the production of steel. The main route for producing iron for steelmaking is to use the blast furnace, which uses metallurgical coke as the reductant. Concerns over the limited resources, the high cost of coking coals, and the environmental impacts of coking and sinter plants have driven steelmakers to develop alternative ironmaking processes that can use non-coking coals to reduce iron ores directly. Since the efficiency and productivity of modern large capacity blast furnaces will be difficult to surpass, blast furnaces will continue to retain their predominant position as the foremost ironmaking process for some time to come. The alternative ironmaking processes are therefore expected to play an increasingly significant role in the iron and steel industry, especially in meeting the needs of small-sized local and regional markets. It is likely that the importance of direct reduced iron (DRI) and hot metal as sources of virgin iron will continue to increase, especially in the developing countries where steelmaking is, and will be, primarily based on electric arc furnace (EAF) minimills. Consequently, the challenges that are faced by the new technology have to be embraced.

  13. Fundamental Study on Coke Degradation in BF with Oxygen Enriched Blast and High Hydrogen Atmosphere

    Institute of Scientific and Technical Information of China (English)

    WANG Ping; LI Jia-xin; ZHOU Li-ying

    2005-01-01

    The effects of gas composition, temperature, ore to coke ratio and prereduction rate of ore on coke degradation were studied. The results showed that 1% increment in solution loss of coke reduces coke strength by 0.6%, and the coke degradation is accelerated with the temperature. The higher the temperature, the more coke surface is involved in reactions, and the less negative effect on coke strength is. Hydrogen exerts stronger effect on coke degradation than CO at high temperature. The coke degradation is decreased with the reduction of ore to coke ratio and increase of ore prereduction rate.

  14. Fundamentals of Delayed Coking Joint Industry Project

    Energy Technology Data Exchange (ETDEWEB)

    Michael Volk Jr; Keith Wisecarver

    2005-10-01

    Delayed coking evolved steadily over the early to mid 1900s to enable refiners to convert high boiling, residual petroleum fractions to light products such as gasoline. Pound for pound, coking is the most energy intensive of any operation in a modern refinery. Large amounts of energy are required to heat the thick, poor-quality petroleum residuum to the 900 to 950 degrees F required to crack the heavy hydrocarbon molecules into lighter, more valuable products. One common misconception of delayed coking is that the product coke is a disadvantage. Although coke is a low valued (near zero economic value) byproduct, compared to transportation fuels, there is a significant worldwide trade and demand for coke as it is an economical fuel. Coke production has increased steadily over the last ten years, with further increases forecast for the foreseeable future. Current domestic production is near 111,000 tons per day. A major driving force behind this increase is the steady decline in crude quality available to refiners. Crude slates are expected to grow heavier with higher sulfur contents while environmental restrictions are expected to significantly reduce the demand for high-sulfur residual fuel oil. Light sweet crudes will continue to be available and in even greater demand than they are today. Refiners will be faced with the choice of purchasing light sweet crudes at a premium price, or adding bottom of the barrel upgrading capability, through additional new investments, to reduce the production of high-sulfur residual fuel oil and increase the production of low-sulfur distillate fuels. A second disadvantage is that liquid products from cokers frequently are unstable, i.e., they rapidly form gum and sediments. Because of intermediate investment and operating costs, delayed coking has increased in popularity among refiners worldwide. Based on the 2000 Worldwide Refining Survey published in the Oil and Gas, the delayed coking capacity for 101 refineries around the world

  15. Upgrading oil sands bitumen with FLUID COKING and FLEXICOKING technologies

    Energy Technology Data Exchange (ETDEWEB)

    Kamienski, P.; Phillips, G. [ExxonMobil Research and Engineering Co., Fairfax, VA (United States); McKnight, C.; Rumball, B. [Syncrude Canada Ltd., Calgary, AB (Canada)

    2009-07-01

    This presentation described EMRE's Fluid Coking and Flexicoking technologies that are well suited for upgrading Alberta's heavy crudes and oil sands bitumen into pipelineable crudes or synthetic crudes, which can be further processed into transportation fuels. The Fluid Coking technology uses a fluidized bed reactor that thermally converts the heavy oils into light gases, liquids and coke. The metals and much of the sulphur are concentrated in the coke. Combustion of the coke provides process heat and the remaining coke is sold or stored on site for later recovery. Syncrude Canada currently operates 3 Fluid Coking units in northern Alberta. Flexicoking extends fluid coking by integrating air gasification to produce a carbon monoxide/hydrogen rich fuel gas that helps meet fuel and energy requirements of bitumen recovery and upgrading. The yields of light gas and liquids are similar to those of the Fluid Coking process. The partial combustion of coke provides the process heat for the thermal conversion and gasification steps. The remaining coke is gasified and desulphurized using Flexsorb technology. At present, there are 5 Flexicoking units in operation around the world. Interest in the technology is growing, particularly in locations with large demand for clean fuel or electricity. It is also suitable for steam assisted gravity drainage (SAGD) operations in Alberta. This presentation outlined the operating principles of the Flexicoking integrated gasification system and compared it with more expensive oxygen gasification processes. tabs., figs.

  16. Alternative method for assessing coking coal plasticity

    Energy Technology Data Exchange (ETDEWEB)

    Dzuy Nguyen; Susan Woodhouse; Merrick Mahoney [University of Adelaide (Australia). BHP Billiton Newcastle Technology Centre

    2008-07-15

    Traditional plasticity measurements for coal have a number of limitations associated with the reproducibility of the tests and their use in predicting coking behaviour. This report reviews alternative rheological methods for characterising the plastic behaviour of coking coals. It reviews the application of more fundamental rheological measurements to the coal system as well as reviewing applications of rheology to other physical systems. These systems may act as potential models for the application of fundamental rheological measurements to cokemaking. The systems considered were polymer melts, coal ash melts, lava, bread making and ice cream. These systems were chosen because they exhibit some physically equivalent processes to the processes occurring during cokemaking, eg, the generation of bubbles within a softened system that then resolidifies. A number of recommendations were made; the steady and oscillatory shear squeeze flow techniques be further investigated to determine if the measured rheology characteristics are related to transformations within the coke oven and the characteristics of resultant coke; modification of Gieseler plastometers for more fundamental rheology measurements not be attempted.

  17. Nitrogen Chemistry and Coke Transformation of FCC Coked Catalyst during the Regeneration Process.

    Science.gov (United States)

    Shi, Junjun; Guan, Jianyu; Guo, Dawei; Zhang, Jiushun; France, Liam John; Wang, Lefu; Li, Xuehui

    2016-06-08

    Regeneration of the coked catalyst is an important process of fluid catalytic cracking (FCC) in petroleum refining, however, this process will emit environmentally harmful gases such as nitrogen and carbon oxides. Transformation of N and C containing compounds in industrial FCC coke under thermal decomposition was investigated via TPD and TPO to examine the evolved gaseous species and TGA, NMR and XPS to analyse the residual coke fraction. Two distinct regions of gas evolution are observed during TPD for the first time, and they arise from decomposition of aliphatic carbons and aromatic carbons. Three types of N species, pyrrolic N, pyridinic N and quaternary N are identified in the FCC coke, the former one is unstable and tends to be decomposed into pyridinic and quaternary N. Mechanisms of NO, CO and CO2 evolution during TPD are proposed and lattice oxygen is suggested to be an important oxygen resource. Regeneration process indicates that coke-C tends to preferentially oxidise compared with coke-N. Hence, new technology for promoting nitrogen-containing compounds conversion will benefit the in-situ reduction of NO by CO during FCC regeneration.

  18. Nitrogen Chemistry and Coke Transformation of FCC Coked Catalyst during the Regeneration Process

    Science.gov (United States)

    Shi, Junjun; Guan, Jianyu; Guo, Dawei; Zhang, Jiushun; France, Liam John; Wang, Lefu; Li, Xuehui

    2016-01-01

    Regeneration of the coked catalyst is an important process of fluid catalytic cracking (FCC) in petroleum refining, however, this process will emit environmentally harmful gases such as nitrogen and carbon oxides. Transformation of N and C containing compounds in industrial FCC coke under thermal decomposition was investigated via TPD and TPO to examine the evolved gaseous species and TGA, NMR and XPS to analyse the residual coke fraction. Two distinct regions of gas evolution are observed during TPD for the first time, and they arise from decomposition of aliphatic carbons and aromatic carbons. Three types of N species, pyrrolic N, pyridinic N and quaternary N are identified in the FCC coke, the former one is unstable and tends to be decomposed into pyridinic and quaternary N. Mechanisms of NO, CO and CO2 evolution during TPD are proposed and lattice oxygen is suggested to be an important oxygen resource. Regeneration process indicates that coke-C tends to preferentially oxidise compared with coke-N. Hence, new technology for promoting nitrogen-containing compounds conversion will benefit the in-situ reduction of NO by CO during FCC regeneration. PMID:27270486

  19. Nitrogen Chemistry and Coke Transformation of FCC Coked Catalyst during the Regeneration Process

    Science.gov (United States)

    Shi, Junjun; Guan, Jianyu; Guo, Dawei; Zhang, Jiushun; France, Liam John; Wang, Lefu; Li, Xuehui

    2016-06-01

    Regeneration of the coked catalyst is an important process of fluid catalytic cracking (FCC) in petroleum refining, however, this process will emit environmentally harmful gases such as nitrogen and carbon oxides. Transformation of N and C containing compounds in industrial FCC coke under thermal decomposition was investigated via TPD and TPO to examine the evolved gaseous species and TGA, NMR and XPS to analyse the residual coke fraction. Two distinct regions of gas evolution are observed during TPD for the first time, and they arise from decomposition of aliphatic carbons and aromatic carbons. Three types of N species, pyrrolic N, pyridinic N and quaternary N are identified in the FCC coke, the former one is unstable and tends to be decomposed into pyridinic and quaternary N. Mechanisms of NO, CO and CO2 evolution during TPD are proposed and lattice oxygen is suggested to be an important oxygen resource. Regeneration process indicates that coke-C tends to preferentially oxidise compared with coke-N. Hence, new technology for promoting nitrogen-containing compounds conversion will benefit the in-situ reduction of NO by CO during FCC regeneration.

  20. Sectionalizing Transformation of the Electricity Supply System for Friction Power Tracks of Coking Ovens%焦炉摩电道供电系统分段改造

    Institute of Scientific and Technical Information of China (English)

    杜颖

    2015-01-01

    对焦炉的四大车即推焦车、装煤车、拦焦车、息焦车的摩电道进行改造,并对摩电道的供电电源进行改造,以提高焦炉四大车摩电道检修时的分段灵活性,从而消除安全隐患,提高焦炉的生产效率。%The friction power-delivery tracks for the four coking oven servicing ma-chines, namely the coke pusher car, charger car, guider car and quenching car, were trans-formed. At the same time the power supply source of the tracks was also upgraded. As a re-sult the maintenance of the friction power tracks was more flexibly sectionalized, which has e-liminated safety dangers and improved coking productivity.

  1. Quenching: fact or fiction?

    Science.gov (United States)

    Basketter, D

    2000-11-01

    Fragrance chemicals are a frequently reported cause of allergic contact dermatitis (ACD), a matter which has recently come into considerable prominence, to the point that legislation in Europe is under serious consideration. Certain skin-sensitizing fragrance chemicals have been reported by the producing industry to be rendered safe (quenched), at least in terms of ACD, when they are used in the presence of a specific quenching agent. Accordingly, it seemed timely to review this apparent quenching phenomenon, considering the available data and potential mechanistic hypotheses that might be used to explain it. If it is correct, it should be a phenomenon of potentially enormous value in the elimination of the allergenic properties of at least a proportion of common skin sensitizers. Whilst there is some evidence in man for the occurrence of quenching during the induction of skin sensitization, a much more substantial body of work has failed to find supportive evidence in various animals models, at a chemical level or at elicitation in human subjects with existing allergy. On balance, it is concluded that quenching of fragrance allergens is a phenomenon still awaiting positive evidence of existence.

  2. Coking coals of Mongolia: Distribution and resources

    Science.gov (United States)

    Erdenetsogt, Bat-Orshikh; Jargal, Luvsanchultem

    2016-04-01

    The coal deposits of Mongolia tend to become younger from west to east and can be subdivided into two provinces, twelve basins, and three areas. Main controlling factor of coal rank is the age of coal bearing sequences. Western Mongolian coal-bearing province contains mostly high rank bituminous coal in strata from Late Carboniferous. The basins in southern Mongolia and the western part of central Mongolia have low rank bituminous coal in strata from the Permian. The northern and central Mongolian basins contain mainly Jurassic subbituminous coal, whereas the Eastern Mongolian province has Lower Cretaceous lignite. Mongolian known coking coal reserves are located in western, southern and northern Mongolia and related to Carboniferous, Permian and Jurassic sequences, respectively. Pennsylvanian Nuurstkhotgor coal deposit is located in northwestern Mongolia (in Western Mongolian coal-bearing province). The coals have 1-7.5 crucible swelling number (CSN) and 0-86 G-index. Vitrinite reflectance value (Rmax in oil) varies from 0.7% to 1.2% and sulfur content is low, ranging from 0.3% to 0.6% with an average of 0.4%. Coal reserve is estimated to be 1.0 billion ton, of which half is coking coal. Upper Permian Khurengol deposit is situated in western Mongolia (in Western Mongolian coal-bearing province). CSN and G-index of coal are 8-9 and 54-99, respectively. The coals have Rmax of 1.1 to 1.7% (average 1.4%) and sulfur content of 0.2 to 0.6% (average 0.4%). Coking coal reserve of the deposit is estimated to be 340 million ton. Upper Permian Tavantolgoi, the largest coking coal deposit, lies in southern Mongolia (in South Gobi coal-bearing basin). The coals have CSN of 1 to 7.5 and Rmax of 0.7% to 1.2%. Sulfur content is low, ranging from 0.5% to 0.9%. Coal reserve is estimated to be 6.0 billion ton, of which 2.0 billion ton is accounted as coking coal. Lower-Middle Jurassic Ovoot coal is located in northern Mongolia (in Orkhon-Selenge coal-bearing area). This is one of

  3. REDUCING POWER PRODUCTION COSTS BY UTILIZING PETROLEUM COKE

    Energy Technology Data Exchange (ETDEWEB)

    Kevin C. Galbreath; Donald L. Toman; Christopher J. Zygarlicke

    1999-09-01

    Petroleum coke, a byproduct of the petroleum-refining process, is an attractive primary or supplemental fuel for power production primarily because of a progressive and predictable increase in the production volumes of petroleum coke (1, 2). Petroleum coke is most commonly blended with coal in proportions suitable to meet sulfur emission compliance. Petroleum coke is generally less reactive than coal; therefore, the cofiring of petroleum coke with coal typically improves ignition, flame stability, and carbon loss relative to the combustion of petroleum coke alone. Although petroleum coke is a desirable fuel for producing relatively inexpensive electrical power, concerns about the effects of petroleum coke blending on combustion and pollution control processes exist in the coal-fired utility industry (3). The Energy & Environmental Research Center (EERC) completed a 2-year technical assessment of petroleum coke as a supplemental fuel. A survey questionnaire was sent to seven electric utility companies that are currently cofiring coal and petroleum coke in an effort to solicit specific suggestions on research needs and fuel selections. An example of the letter and survey questionnaire is presented in Appendix A. Interest was expressed by most utilities in evaluating the effects of petroleum coke blending on grindability, combustion reactivity, fouling, slagging, and fly ash emissions control. Unexpectedly, concern over corrosion was not expressed by the utilities contacted. Although all seven utilities responded to the question, only two utilities, Northern States Power Company (NSP) and Ameren, sent fuels to the EERC for evaluation. Both utilities sent subbituminous coals from the Power River Basin and petroleum shot coke samples. Petroleum shot coke is produced unintentionally during operational upsets in the petroleum refining process. This report evaluates the effects of petroleum shot coke blending on grindability, fuel reactivity, fouling/slagging, and

  4. Inhomogeneous Thermal Quenches

    CERN Document Server

    Sohrabi, Kiyoumars A

    2015-01-01

    We describe holographic thermal quenches that are inhomogeneous in space. The main characteristic of the quench is to take the system far from its equilibrium configuration. Except special extreme cases, the problem has no analytic solution. Using the numerical holography methods, we study different observables that measure thermalization such as the time evolution of the horizon, two-point Wightman function and entanglement entropy (EE). Having an extra nontrivial spacial direction, allows us to study this peculiar generalization since we categorize the problem based on whether we do the measurements along this special direction or perpendicular to it. Exciting new features appear that are absent in the common computations in the literature, the appearance of negative EE valleys surrounding the positive EE hills and abrupt quenches that occupy the whole space at their universal limit are some of the results of this paper. We have tried to provide physical explanations wherever possible. The physical picture ...

  5. The Quench Action

    Science.gov (United States)

    Caux, Jean-Sébastien

    2016-06-01

    We give a pedagogical introduction to the methodology of the Quench Action, which is an effective representation for the calculation of time-dependent expectation values of physical operators following a generic out-of-equilibrium state preparation protocol (for example a quantum quench). The representation, originally introduced in Caux and Essler (2013 Phys. Rev. Lett. 110 257203), is founded on a mixture of exact data for overlaps together with variational reasonings. It is argued to be quite generally valid and thermodynamically exact for arbitrary times after the quench (from short times all the way up to the steady state), and applicable to a wide class of physically relevant observables. Here, we introduce the method and its language, give an overview of some recent results, suggest a roadmap and offer some perspectives on possible future research directions.

  6. Quantum quenches during inflation

    CERN Document Server

    Carrilho, Pedro

    2016-01-01

    We propose a new technique to study fast transitions during inflation, by studying the dynamics of quantum quenches in an $O(N)$ scalar field theory in de Sitter spacetime. We compute the time evolution of the system using a non-perturbative large-$N$ limit approach. We derive the self-consistent mass equation for several physically relevant transitions of the parameters of the theory, in a slow motion approximation. Our computations reveal that the effective mass after the quench evolves in the direction of recovering its value before the quench, but stopping at a different asymptotic value, in which the mass is strictly positive. Furthermore, we tentatively find situations in which the effective mass can be temporarily negative, thus breaking the $O(N)$ symmetry of the system for a certain time, only to then come back to a positive value, restoring the symmetry. We argue the relevance of our new method in a cosmological scenario.

  7. Cleaning dusty gas wastes in the coking industry

    Energy Technology Data Exchange (ETDEWEB)

    Andreikov, E.I.; Anan' ina, L.P.; Zhilina, N.B.; Malysheva, N.V.; Zaidenberg, M.A.; Borodin, V.I.; Lisachenko, A.S.

    1986-02-01

    Gas wastes in coking industry contain coal and semicoke dust covered with tarry substances which prevent them being cleaned on the fixed bed of a catalyst. The paper examines whether it is possible to clean dusty gases of this type using a fluidized bed catalyst. Laboratory experiments using a continuous-flow reactor (diameter 0.02 m, height 0.2 m) and a gas supply rate of 9.6 x 10/sup -2/ m/sup 3//h are described. A mixture of aromatic hydrocarbons (concentration in gas phase - 3 g/m/sup 3/) was oxidized and the degree of conversion of the hydrocarbons was assessed by the amount of CO/sub 2/ found in the test reactor in comparison with that found in a control reactor with an AP-56 catalyst at 500 C; the CO/sub 2/ content was determined by chromatography. Dust content in the air at the fluidized bed was 6.5 g/m/sup 3/ and the amount of tar on the dust surfaces was 8%. Copper-vanadium oxide catalyst was found to work best at 450-550 C; higher temperatures reduce conversion rate (e.g. 3 hours at 720 C gave only 89% conversion). Volatile and tarry substances are absorbed, the amount of CO/sub 2/ in the gases increases and coal particles are converted to semicoke. The resulting dry dust is easier to collect in a dust collector. A pilot run at Khar'kov experimental coking plant resulted in 97.8% of hydrocarbons being romoved as well as 96% of CO. 3 references.

  8. Metallurgical coke quality depending on the variability of properties of coking coal mixes components

    Energy Technology Data Exchange (ETDEWEB)

    M. Kaloc; S. Bartusek; S. Czudek [VSB-TU Ostrava (Czech Republic)

    2005-07-01

    The main sources for this report are the experiences acquired by the long lasting practice of the coking coal mixes preparing and tuning them in accordance with the variable qualitative properties of the coals mined in the coalfields of the OKD Company Ostrava. The systematic database, made by summarizing the values of measured indexes, became a very useful instrument for the coal mixes composing with regard on the two today very important points of view, namely: Contemporary presence and the long lasting availability of the definite coal type from any local source. Price basis influencing strongly the economics of the coke production. The method of prognostic estimating of the metallurgical coke quality dependence on the coking mixes composition, developed some time ago by authors of presented paper, was published in the Cokemaking International Vol. 13, 2/2001 (Czudek S. and al.: Simulation of Carbonization Process under Laboratory Conditions). The original procedure was newly accomplished by implementing a special method of the multi criteria evaluation of the definite coal components. New method is based on special processing of the technologic significant qualitative properties of the mined coal brands enabling deeply estimate the impacts of their application in metallurgical coke production. The importance of this evaluating system exceeds largely the well known method that is incorporated in the international coal classification. The main advantage of the new method is the fully respecting of the specialties marking the geographic different coalfields. (Abstract only)

  9. A device for interlocking coking machines

    Energy Technology Data Exchange (ETDEWEB)

    Bannikov, L.S.; Mil' ko, M.S.; Rodenko, B.V.; Skol' skii, V.M.; Voloshenko, I.P.; Yakushina, E.N.

    1980-03-18

    This device, which contains a high frequency oscillator in the door hoisting mechanism and a high-frequency oscillations receiver in the coke lifting-out device and a communications line for each of the furnaces in the form of tie couplers, is characterized by an arrangement whereby it is equipped with jumpers. This arrangement guarantees a steady operational level of the signal and increases the reliability of the device.

  10. Study on combustion characteristics of petroleum coke residual oil slurry

    Energy Technology Data Exchange (ETDEWEB)

    Shou Weiyi; Xu Xiaoming; Cao Xinyu [and others

    1997-07-01

    Petroleum coke residual oil slurry (POS) is one of prospect substitute of oil burned in many industrial boilers and utilities in China. It is a mixture of pulverized petroleum coke, residual oil and slurry oil. We carried out a series of experiments to study its ignition and combustion mechanism. Experimental results show that the ignition temperature of petroleum coke is higher than normal anthracite and meager coal, and it is difficult to be burned in oil-fired furnace directly. The petroleum coke`s combustion property is improved greatly after mixing with residual oil and slurry oil. The combustion process of POS can be divided into three phases: preheating, kindling and homogenous combustion, burning of the petroleum coke residue. The combustion condition of POS is close to bituminous and coal-oil-mixture (COM).

  11. Characterisation of coking activity during supercritical hydrocarbon pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Gascoin, Nicolas; Gillard, Philippe; Bernard, Stephane [Laboratoire Energetique, Explosion, Structure, UPRES-EA 1205, 63, avenue de Lattre de Tassigny, 18020 Bourges Cedex (France); Bouchez, Marc [MBDA France, 8, rue Le Brix, 18000 Bourges (France)

    2008-12-15

    The active cooling of the Supersonic Combustion Ramjet engine, for hypersonic flight purpose, is ensured thanks to fuel, n-dodecane for the present study. The endothermic fuel pyrolysis, starting above 800 K, could generate an unwanted coke formation. Experimental tests up to 1125 K and between 1 MPa and 6 MPa have been performed on the hydrocarbon fuel pyrolysis to evaluate the coking activity. 316L stainless steel, low carbon steel and titanium reactors have been considered. A witness of the coke formation, based on its thermal insulation and pressure loss effects, has been found. A correlation between methane production and coke deposit was found. The coke has been studied with Scanning Electron Microscope (SEM), Energy Dispersion Spectroscopy (EDS), X-ray diffractometer and Fourier Transform Infrared (FTIR) spectroscopy. The porosity, the density and the permeability of the coke have been estimated. (author)

  12. Quench studies of ILC cavities

    Energy Technology Data Exchange (ETDEWEB)

    Eremeev, Grigory; Geng, Rongli; Palczewski, Ari; Dai, Jin

    2011-07-01

    Quench limits accelerating gradient in SRF cavities to a gradient lower than theoretically expected for superconducting niobium. Identification of the quenching site with thermometry and OST, optical inspection, and replica of the culprit is an ongoing effort at Jefferson Lab aimed at better understanding of this limiting phenomenon. In this contribution we present our finding with several SRF cavities that were limited by quench.

  13. EPA Administrative Order on Consent (AOC) with ERP Compliant Coke, LLC

    Science.gov (United States)

    This Administrative Order on Consent with ERP Compliant Coke was effective August 2016. The Walter Coke facility located in North Birmingham was purchased by ERP Compliant Coke, LLC in February 2016 out of bankruptcy proceedings.

  14. Quenched effective population size

    CERN Document Server

    Sagitov, Serik; Vatutin, Vladimir

    2010-01-01

    We study the genealogy of a geographically - or otherwise - structured version of the Wright-Fisher population model with fast migration. The new feature is that migration probabilities may change in a random fashion. Applying Takahashi's results on Markov chains with random transition matrices, we establish convergence to the Kingman coalescent, as the population size goes to infinity. This brings a novel formula for the coalescent effective population size (EPS). We call it a quenched EPS to emphasize the key feature of our model - random environment. The quenched EPS is compared with an annealed (mean-field) EPS which describes the case of constant migration probabilities obtained by averaging the random migration probabilities over possible environments.

  15. Calculating Quenching Weights

    CERN Document Server

    Salgado, C A; Salgado, Carlos A.; Wiedemann, Urs Achim

    2003-01-01

    We calculate the probability (``quenching weight'') that a hard parton radiates an additional energy fraction due to scattering in spatially extended QCD matter. This study is based on an exact treatment of finite in-medium path length, it includes the case of a dynamically expanding medium, and it extends to the angular dependence of the medium-induced gluon radiation pattern. All calculations are done in the multiple soft scattering approximation (Baier-Dokshitzer-Mueller-Peign\\'e-Schiff--Zakharov ``BDMPS-Z''-formalism) and in the single hard scattering approximation (N=1 opacity approximation). By comparison, we establish a simple relation between transport coefficient, Debye screening mass and opacity, for which both approximations lead to comparable results. Together with this paper, a CPU-inexpensive numerical subroutine for calculating quenching weights is provided electronically. To illustrate its applications, we discuss the suppression of hadronic transverse momentum spectra in nucleus-nucleus colli...

  16. Phenomenology of Holographic Quenches

    Science.gov (United States)

    da Silva, Emilia; Lopez, Esperanza; Mas, Javier; Serantes, Alexandre

    2015-10-01

    We study holographic models related to global quantum quenches in finite size systems. The holographic set up describes naturally a CFT, which we consider on a circle and a sphere. The enhanced symmetry of the conformal group on the circle motivates us to compare the evolution in both cases. Depending on the initial conditions, the dual geometry exhibits oscillations that we holographically interpret as revivals of the initial field theory state. On the sphere, this only happens when the energy density created by the quench is small compared to the system size. However on the circle considerably larger energy densities are compatible with revivals. Two different timescales emerge in this latter case. A collapse time, when the system appears to have dephased, and the revival time, when after rephasing the initial state is partially recovered. The ratio of these two times depends upon the initial conditions in a similar way to what is observed in some experimental setups exhibiting collapse and revivals.

  17. Visualization of coke state in hydraulic decoking process

    Science.gov (United States)

    Guo, Qian; Tong, Xinglin; Deng, Chengwei; Zhang, Cui; Huang, Di; Chen, Liang; Xiong, Jiaguo

    2016-05-01

    The relationship model of the sound signal and the coke state can be established through multiple test and comparison of the noise signal and the coke operation. By collecting data, we summarize the main frequency power fluctuation range of the sound signal in kinds of state, and extract the nearest 5 decision results for reference. The weighted value of each result according to the update time has gradually increased. On the basis of that, we developed visualization software, real-time reflect out coke coking tower state. Animation refresh rate is second level, and the vertical height can be accurate to 0.1m.

  18. Full scale treatment of phenolic coke coking waste water under unsteady conditions

    Energy Technology Data Exchange (ETDEWEB)

    Suschka, Jan [Institute for Ecology of Industrial Areas, Katowice (Poland); Morel, Jacek; Mierzwinski, Stanislaw; Januszek, Ryszard [Coke Plant Przyjazn, Dabrowa Gornicza (Poland)

    1993-12-31

    Phenolic waste water from the largest coke coking plant in Poland is treated at a full technical scale. From the very beginning it became evident that very high qualitative variations in short and long periods were to be expected. For this purpose, the biological treatment plant based on activated sludge is protected through preliminary physical-chemical treatment and the results are secured by a final chemical stage of treatment. Nevertheless, improvements in the performance of the treatment plant have been found necessary to introduce. In this work, the experience gained over the last five years is described and developed improvements were presented. 3 refs., 9 figs., 1 tab.

  19. Coal Beneficiation Technology for Coking & Non-Coking Coal Meant For Steel and Thermal Power Plants

    OpenAIRE

    Manoj Kumar Sharma; Gohil Priyank; Nikita Sharma

    2015-01-01

    There are 21 coking coal washeries in production both in private and public sectors. Production of clean coal in these washeries during 1989-90 was 12 million tonne and it is expected to go up to 37 million, tonne during 2015-16. Planning Commission has taken the decision that non-coking coal meant for Thermal Power Plants situated far away from feeding coalfield, should be beneficiated. Coal Washing is a process of separation mainly based on difference in Specific Gravity of Coal and associa...

  20. Organic synthesis by quench reactions. [in prebiotic simulation experiment

    Science.gov (United States)

    Park, W. K.; Hochstim, A. R.; Ponnamperuma, C.

    1975-01-01

    Study of the effects of chemical quench reactions on the formation of organic compounds at a water surface under simulated primordial earth conditions. A mixture of gaseous methane and ammonia over a water surface was exposed to an arc discharge between an electrode and the water surface, generating reactive species. Various organic molecules were formed by a subsequent quenching of these species generated on the water surface. The effects of these water-surface quench reactions were assessed by comparing the amounts of synthesized molecules to the amounts which formed during the discharge of an arc above the water level. It is concluded that the quench (or wet) discharge led to faster rates of reactions, higher-molecular-weight organic compounds, and one-order-of-magnitude larger yields than the dry discharge.

  1. Organic synthesis by quench reactions. [in prebiotic simulation experiment

    Science.gov (United States)

    Park, W. K.; Hochstim, A. R.; Ponnamperuma, C.

    1975-01-01

    Study of the effects of chemical quench reactions on the formation of organic compounds at a water surface under simulated primordial earth conditions. A mixture of gaseous methane and ammonia over a water surface was exposed to an arc discharge between an electrode and the water surface, generating reactive species. Various organic molecules were formed by a subsequent quenching of these species generated on the water surface. The effects of these water-surface quench reactions were assessed by comparing the amounts of synthesized molecules to the amounts which formed during the discharge of an arc above the water level. It is concluded that the quench (or wet) discharge led to faster rates of reactions, higher-molecular-weight organic compounds, and one-order-of-magnitude larger yields than the dry discharge.

  2. Rheocasting a Zn-Al composite reinforced with coke dust

    Science.gov (United States)

    Madroñero, A.; Cruz, J.; Foruria, C.; Coleto, J.

    1997-01-01

    This article details research conducted to establish the optimum parameters needed to rheocast a zinc-aluminum alloy reinforced with coke-dust particles. Based on the experiments, a composite with a 10 vol.% coke-particulate reinforcement was found to exhibit good metallurgical quality (e.g., low porosity and the absence of clustering) in the final product.

  3. New functional units for coke machine automatic control system

    Energy Technology Data Exchange (ETDEWEB)

    Parfenov, G.I.; Bannikov, L.S.; Vakarenko, I.M.; Grishin, S.P.

    1983-01-01

    A new device used in the control systems of coking plants is discussed. The system is capable of operating in fully automatic, semi-automatic, or manual modes. Examples of the usage of the unit include the stopping of coke machines within limits of +/- 200 mm. It is concluded that the use of the units reduce manufacture, adjustment, and service costs.

  4. Combustion kinetics of the coke on deactivated dehydrogenation catalysts

    NARCIS (Netherlands)

    Luo, Sha; He, Songbo; Li, XianRu; Li, Jingqiu; Bi, Wenjun; Sun, Chenglin

    2015-01-01

    The coke combustion kinetics on the deactivated catalysts for long chain paraffin dehydrogenation was studied by the thermogravimetry and differential thermogravimetry (TG–DTG) technique. The amount and H/C mole ratio of the coke were determined by the TG and elemental analysis. And the comprehensiv

  5. Effect of physical disturbance on the structure of needle coke

    Science.gov (United States)

    Zhao, Shi-Gui; Wang, Bao-Cheng; Sun, Quan

    2010-10-01

    Through different preparation technology, this paper reports that the needle coke is prepared with coal-tar pitch under the effect of magnetic field and ultrasonic cavitation. It studies the effect of physical disturbance on the structure of needle coke. The structure of needle coke is characterized by scanning electron microscope and x-ray diffractometer, and the influence mechanism is analysed. Results showed that the structure and property of needle coke could be effectively improved by magnetic field and ultrasonic cavitations, such as degree of order, degree of graphitization and crystallization. Comparatively speaking, the effect of magnetic field was greater. The graphitization degree of needle coke prepared under the effect of magnetic field is up to 45.35%.

  6. Design of Industrial Quenching Processes

    Institute of Scientific and Technical Information of China (English)

    Nikolai. I. KOBASKO; George .E. TOTTEN

    2004-01-01

    The method of designing industrial processes of quench cooling, in particular, the speed of the conveyor movement with regard to shape and sizes of parts to be quenched, thermal and physical properties of material and cooling capacity of quenchants has been developed. The suggested designing method and databases are the basis for the complete automation of industrial processes of quench cooling, especially for continuous conveyor lines, with the purpose of making high-strength materials. The process is controlled by infrared technique.

  7. Effect of nut coke on the performance of the ironmaking blast furnace

    NARCIS (Netherlands)

    Song, Q.

    2013-01-01

    The blast furnace consumes a large amount of high quality metallurgy coke (size 35-80 mm) in addition to ore in the form of pellets and sinter. This coke is the coarse fraction, derived from the coke plant. The fine fraction (8 -35 mm), arise after sieving, named nut coke, can’t be directly used in

  8. Effect of nut coke on the performance of the ironmaking blast furnace

    NARCIS (Netherlands)

    Song, Q.

    2013-01-01

    The blast furnace consumes a large amount of high quality metallurgy coke (size 35-80 mm) in addition to ore in the form of pellets and sinter. This coke is the coarse fraction, derived from the coke plant. The fine fraction (8 -35 mm), arise after sieving, named nut coke, can’t be directly used in

  9. Coke Oven Gas Based Methanol Production Capacity Reached 1.2 Mt/a in China

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Coke oven gas is one of the main byproducts of coke chemicals industry.One ton of coke formed can generate 430 m3of coke oven gas.Adoption of appropriate chemical processing method can convert methane contained in the coke oven gas into CO that can be further converted into methanol.It is learned that currently China has constructed and commissioned ten projects for manufacture of methanol fromcoke oven gas with the total production capacity reaching 1.2 Mt/a methanol.More than twenty coke gas-to-methanol units are under construction or in the stage of project design with their overall production capacity reaching nearly 3.0 Mt/a methanol.Relevant experts have indicated that the enterprises provided with coke production lines are capable of constructing coke gas-to-methanol projects to realize coproduction of coke and methanol while utilizing their own coke gas resources.

  10. Research on the evolvement of morphology of coking coal during the coking process.

    Science.gov (United States)

    Zhong, Xiangyun; Wu, Shiyong; Liu, Yang; Zhao, Zhenning; Zhang, Yaru; Bai, Jinfeng; Xu, Jun; Xi, Bai

    2013-12-01

    The evolvement of morphology and structure of the coal with different metamorphic degrees during coking process in the vertical furnace was investigated by infrared Image detector. Moreover, the temperature distribution in the radial direction and the crack formation were also studied in heating process. The results show that the amount of crack and the shrinkage level of char decrease with the coal rank rising. In addition, the initial temperature of crack formation for char increases with the coal rank rising.

  11. The effect of blast furnace coke quality on the possibility of its use

    OpenAIRE

    A. Konstanciak

    2013-01-01

    In the paper behavior of the blast-furnace coke in the high temperature was presented. Comparative analysis of the chemical composition of the blast-furnace coke and the heat treatment of it were done. Coefficients M10 and M40 with the thermo-abrasiveness for chosen cokes were compared. The influence of ash content of the coke on the blast-furnace bed permeability was defined. Usefulness of the coke to blast-furnace process was also defined.

  12. RESEARCH ON THE QUALITY PRICE RATIO OF COKING COAL

    Institute of Scientific and Technical Information of China (English)

    陶树人; 王永君

    1994-01-01

    If assortment price parity of Clean coling coal and its quallty price difference is nonreasortable, it doesn't guide in improving the qualiry metaljurgical eoking coal and may be influence the economic benefit of metallurgical enterprises. This paper propose the principles and mathematic model for determination assortment parity of ciean cokingcoal and its quality difference of ash content in clean coking coa in order to urge wasberies into producing superior clean coking coal which is under condition of consideration both intorest waskcries and interest metallurgical industry. It canbe used as a method in theory to make price stra,iegics under condition of socialism maket economic for washeries of clean coking coal

  13. A randomized, double-blind, placebo-controlled trial of the effect of dried purple carrot on body mass, lipids, blood pressure, body composition, and inflammatory markers in overweight and obese adults: the QUENCH trial.

    Science.gov (United States)

    Wright, Olivia R L; Netzel, Gabriele A; Sakzewski, Amy R

    2013-06-01

    Obesity is a significant health issue worldwide and is associated with chronic, low-grade inflammation predisposing the individual to cardiovascular disease and impaired blood glucose homeostasis. Anthocyanins and phenolic acids from purple carrots are effective at reversing inflammation and metabolic alterations in animal models, potentially through inhibition of inflammatory pathways. The effects of dried purple carrot on body mass, body composition, blood pressure, lipids, inflammatory markers, liver function tests, and appetite were investigated in 16 males (aged 53.1 ± 7.6 years and with a mean BMI of 32.8 ± 4.6 kg/m(2)) with normal lipid and inflammatory markers. There was no evidence that 118.5 mg/day of anthocyanins and 259.2 mg/day of phenolic acids for 4 weeks resulted in statistically significant changes in body mass, body composition, appetite, dietary intake, low density lipoprotein, total cholesterol, blood pressure, or C-reactive protein in these obese participants at the dose and length of intervention used in this trial. High density lipoprotein cholesterol was lower in the intervention group (p < 0.05). Aspartate amino transferase and alanine amino transferase did not change, indicating that the intervention was safe. More studies are required to establish the bioavailability and pharmacokinetic effects of purple carrot anthocyanins and phenolic acids prior to further trials of efficacy with respect to treating inflammation and metabolic alterations.

  14. Processing of converter sludges on the basis of thermal-oxidative coking with coals

    Science.gov (United States)

    Kuznetsov, S. N.; Shkoller, M. B.; Protopopov, E. V.; Kazimirov, S. A.; Temlyantsev, M. V.

    2017-09-01

    The paper deals with the solution of an important problem related to the recycling of converter sludge. High moisture and fine fractional composition of waste causes the application of their deep dehydration and lumping. To reduce environmental emissions the non-thermal method of dehydration is considered – adsorption-contact drying. As a sorbent, the pyrolysis product of coals from the Kansko-Achinsky basin – brown coal semi-coke (BSC) obtained by the technology “Thermokoks”. Experimental data on the dehydration of high-moisture wastes with the help of BSC showed high efficiency of the selected material. The lumping of the dried converter dust was carried out by thermo-chemical coking with coals of grades GZh (gas fat coal) and Zh (fat coal). As a result, an iron-containing product was obtained – ferrocoke, which is characterized by almost complete reduction of iron oxides, as well as zinc transition into a vapor state, and is removed with gaseous process products. Based on the results of the experimental data a process basic diagram of the utilization of converter sludge to produce ferrocoke was, which can be effectively used in various metallurgical aggregates, for example, blast furnaces, converters and electric arc furnaces. In the basic technological scheme heat generated by ferrocoke cooling and the energy of the combustion products after the separation of zinc in the gas turbine plant will be used.

  15. Different solvents for the regeneration of the exhausted activated carbon used in the treatment of coking wastewater.

    Science.gov (United States)

    Guo, Dongsheng; Shi, Qiantao; He, Binbin; Yuan, Xiaoying

    2011-02-28

    The solvents n-pentane, methylene dichloride, ethyl ether and dodecylbenzenesulphonic acid sodium were used to regenerate exhausted activated carbon used in the process of treating coking wastewater, and the efficiency, ability, and optimum conditions of the different solvents on this regeneration were investigated. The results indicate that n-pentane could effectively remove refractory organic compounds in the coking wastewater adsorbed on the surface of activated carbon and could repeatedly regenerate the exhausted activated carbon to recover its adsorption activity. Under the conditions of a regeneration time of 20 min, a regeneration temperature of 25°C, an activated carbon drying time of 300 min, and an activated carbon drying temperature of 150°C, n-pentane had the best regeneration efficiency, at 98.27%, for exhausted activated carbon. Gas chromatography-mass spectrometry analysis results show that the nature of the activated carbon regenerated by organic solvents had no remarkable change in adsorption for the main types of organic compounds in coking wastewater. The good regenerative effect of n-pentane on the activated carbon may be due its stronger desorption of esters embedded within the internal structure of activated carbon.

  16. Dry Eye

    Science.gov (United States)

    ... Eye > Facts About Dry Eye Facts About Dry Eye This information was developed by the National Eye ... the best person to answer specific questions. Dry Eye Defined What is dry eye? Dry eye occurs ...

  17. Carbonization behaviour of woody biomass and resulting metallurgical coke properties

    Energy Technology Data Exchange (ETDEWEB)

    Matsumura, T.; Ichida, M.; Nagasaka, T.; Kato, K. [Tohoku University, Miyagi (Japan). Graduate School for Environmental Studies

    2008-07-01

    The technology using waste wood from construction and thinned wood that are not recycled in the woody biomass as one of raw materials for producing metallurgical coke was examined in detail by adding them to coal and carbonizing them. In the carbonization tests, four types of woody biomasses showed substantially almost the same results in respect to material balance and composition of carbonized products. Compared with raw woods, woody biomasses compressively formed to not smaller than 10 mm permit an increase in the addition rate to 1.5% while inhibiting the lowering of coke strength. Hot compressive forming at 200-350 degrees C where pyrolysis of woody biomass occurs inhibits the lowering of coke strength and will therefore permit an increase in the use of woody biomasses. As a result, the possibility to use as a raw material for the coke manufacturing by adding the compressively formed woody biomass was found.

  18. RESIDUA UPGRADING EFFICIENCY IMPROVEMENT MODELS: WRI COKING INDEXES

    Energy Technology Data Exchange (ETDEWEB)

    John F. Schabron; Joseph F. Rovani, Jr.; Francis P. Miknis; Thomas F. Turner

    2003-06-01

    Pyrolysis experiments were conducted with three residua at 400 C (752 F) at various residence times. The wt % coke and gaseous products were measured for the product oils. The Western Research Institute (WRI) Coking Indexes were determined for the product oils. Measurements were made using techniques that might correlate with the Coking Indexes. These included spin-echo proton nuclear magnetic resonance spectroscopy, heat capacity measurements at 280 C (536 F), and ultrasonic attenuation. The two immiscible liquid phases that form once coke formation begins were isolated and characterized for a Boscan residuum pyrolyzed at 400 C (752 F) for 55 minutes. These materials were analyzed for elemental composition (CHNS), porphyrins, and metals (Ni,V) content.

  19. Prediction of coking dynamics for wet coal charge

    Directory of Open Access Journals (Sweden)

    Kardaś Dariusz

    2015-09-01

    Full Text Available A one-dimensional transient mathematical model describing thermal and flow phenomena during coal coking in an oven chamber was studied in the paper. It also accounts for heat conduction in the ceramic oven wall when assuming a constant temperature at the heating channel side. The model was solved numerically using partly implicit methods for gas flow and heat transfer problems. The histories of temperature, gas evolution and internal pressure were presented and analysed. The theoretical predictions of temperature change in the centre plane of the coke oven were compared with industrialscale measurements. Both, the experimental data and obtained numerical results show that moisture content determines the coking process dynamics, lagging the temperature increase above the water steam evaporation temperature and in consequence the total coking time. The phenomenon of internal pressure generation in the context of overlapping effects of simultaneously occurring coal transitions - devolatilisation and coal permeability decrease under plastic stage - was also discussed.

  20. RESIDUA UPGRADING EFFICIENCY IMPROVEMENT MODELS: WRI COKING INDEXES

    Energy Technology Data Exchange (ETDEWEB)

    John F. Schabron; Joseph F. Rovani, Jr.; Francis P. Miknis; Thomas F. Turner

    2003-06-01

    Pyrolysis experiments were conducted with three residua at 400 C (752 F) at various residence times. The wt % coke and gaseous products were measured for the product oils. The Western Research Institute (WRI) Coking Indexes were determined for the product oils. Measurements were made using techniques that might correlate with the Coking Indexes. These included spin-echo proton nuclear magnetic resonance spectroscopy, heat capacity measurements at 280 C (536 F), and ultrasonic attenuation. The two immiscible liquid phases that form once coke formation begins were isolated and characterized for a Boscan residuum pyrolyzed at 400 C (752 F) for 55 minutes. These materials were analyzed for elemental composition (CHNS), porphyrins, and metals (Ni,V) content.

  1. Mathematical modeling of a rotary hearth coke calciner

    Directory of Open Access Journals (Sweden)

    Hilde C. Meisingset

    1995-10-01

    Full Text Available A mathematical model of a rotary hearth coke calciner is developed. The model is based on first principles including the most important dynamic phenomena. The model is a thermodynamic model involving heat and mass transfer and chemical reactions. Fundamental mass and energy balance equations for the coke phase, the gas phase and the lining are formulated. For the gas phase, a stationary model is used. The equations are solved numerically, and simulated temperature profiles are shown in this paper.

  2. Technology of separation of hydrogen from coke oven gas

    Energy Technology Data Exchange (ETDEWEB)

    Budner, Z.; Morawiec, B.

    1989-01-01

    A process to beindustrialised at the Zdzieszowice coking plant and Kedzierzyn fertiliser works is described. Coke oven gas is scrubbed with methanol and subjected to pressure-swing adsorption. The hydrogen-rich fraction is converted with steam to reduce its CO content and then subjected again to pressure-swing adsorption. The methane-rich fraction from the first PSA stage is processed to 90% CH{sub 4} and a fraction containing 35% ethylene and 10% ethane.

  3. Repairing the wooden frame of chambers in coking furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Nador, Y.; Iruti, M.; Komiya, S.; Matsuno, T.; Ogavakhara, F.

    1983-02-12

    A method and device are proposed for hot repair of the door frames of coking chanbers. The repair is conducted prior to discharge of the coke from the chamber without its cooling or a reduction in temperature. After the doors are removed, a screening plate fettled with a heat insulation material on the chamber side is introduced into the frame, it is attached to the door frame and the required repair is conducted.

  4. Use of thermogravimetry for proximate analysis of coals and cokes

    Energy Technology Data Exchange (ETDEWEB)

    Ottaway, M.

    1982-08-01

    An alternative method for the proximate analysis of coals and cokes using a thermobalance is described. The test measures water content, volatile matter, fixed carbon, and ash residue and takes <10 min to complete. The variety of coals and cokes tested in this investigation have given results which showed good correlation with values from the prescribed method. The thermogravimetric technique appears to be a feasible rapid alternative to standard methods for proximate analysis. (11 refs.)

  5. Optimal control structure of combustion in coke oven battery

    Directory of Open Access Journals (Sweden)

    Karol Kostúr

    2006-10-01

    Full Text Available Big energetic aggregates require a complicated control system, which provide an effective running or production. Among these aggregates belongs the coke – oven battery. This article contains a proposal of the two – level control system. The basic control is realized by a direct digital control. The advanced control continuously optimalizes regulator parameters of the basic control. The present control system has been verified in real conditions of a coking plant.

  6. Mineral matter in coals and their reactions during coking

    Energy Technology Data Exchange (ETDEWEB)

    Grigore, Mihaela; French, David [The Commonwealth Scientific and Industrial Research Organisation (CSIRO) - Energy Technology, Lucas Heights, NSW 2234 (Australia); Sakurovs, Richard [The Commonwealth Scientific and Industrial Research Organisation (CSIRO) - Energy Technology, Newcastle, NSW 2300 (Australia); Sahajwalla, Veena [School of Materials Science and Engineering, The University of New South Wales, Sydney, NSW 2052 (Australia)

    2008-12-01

    Degradation of coke in the blast furnace is influenced by its inherent mineral matter, the formation of which is itself dependent upon the nature of the coal mineral matter. To date few studies have been made of coke mineralogy and its relationship to the mineralogy of the parent coal. In this study the effect of carbonisation on coal mineral matter has been investigated by a detailed quantitative mineralogical examination of nine cokes and their parent coals. The quantitative analysis was performed on X-ray diffraction patterns of the mineral matter of cokes and coals, using SIROQUANT {sup trademark}. Coke mineralogy and its composition varied strongly between cokes, more strongly than variations in elemental composition of the ash. The mineral matter in the studied cokes consisted of crystalline mineral phases and also significant levels of amorphous phase (ranging between 44 and 75%). Decomposition of clays such as kaolinite, montmorillonite, illite and chamosite produced the amorphous phase and some of the crystalline mineral phases such as mullite, {gamma}-alumina, spinel, cristobalite and leucite. The type of association of mineral matter in coals had an important role in how the clays decomposed. For example, association of kaolinite with silica-bearing minerals in intimate intermixture favoured formation of mullite over {gamma}-alumina. Akermanite and diopside result from reaction of kaolinite with associated calcium bearing minerals (calcite, dolomite or ankerite). Quartz, fluorapatite and the three polymorphs of TiO{sub 2} (anatase, brookite and rutile) were the coal minerals that were least affected during carbonisation, as they were also found in the cokes, yet even they were affected in some cases. (author)

  7. Correlation between porous structure and fracture stress for metallurgical coke

    Energy Technology Data Exchange (ETDEWEB)

    Gardien, J.F.; Lemaire, E.; Dubs, A.; Osmont, P.; Laurent, J.P.; Steiler, J.M. (Institut de Recherches de la Siderurgie Francaise, Maizieres-les-Metz (France))

    1994-05-26

    Various samples of coke have been characterized by diametral compression and the geometry of the porous network has been analysed in terms of fractal structure. It is found that the coke studied exhibits a fractal behaviour on at least two decades. Diametral compression test leads to two different ways of breaking; brittle fracture, and in some cases complex fracture. As expected, the fracture stress is not linked with the fractal dimension in case of brittle fracture, but with the mean size of the largest pores. In case of complex loading conditions, the fracture strength is linked with the fractal dimension. The models of Cook and of Anderson, which integrate fractal description of porous materials in Griffith's theory, do not seem to be valid concerning coke material. The present approach of characterising the porous structure of coke by the fractal dimension seems adapted to explain coke strength, especially under complex stress conditions, but should be extended to an increased number of coke type samples.

  8. Assessment of thermal efficiency of heat recovery coke making

    Science.gov (United States)

    Tiwari, H. P.; Saxena, V. K.; Haldar, S. K.; Sriramoju, S. K.

    2017-02-01

    The heat recovery stamp charge coke making process is quite complicated due to the evolved volatile matter during coking, is partially combusted in oven crown and sole flue in a controlled manner to provide heat for producing metallurgical coke. Therefore, the control and efficient utilization of heat in the oven crown, and sole flue is difficult, which directly affects the operational efficiency. Considering the complexity and importance of thermal efficiency, evolution of different gases, combustion of gasses in oven crown and sole flue, and heating process of coke oven has been studied. A nonlinear regression methodology was used to predict temperature profile of different depth of coal cake during the coking. It was observed that the predicted temperature profile is in good agreement with the actual temperature profile (R2 = 0.98) and is validated with the actual temperature profile of other ovens. A complete study is being done to calculate the material balance, heat balance, and heat losses. This gives an overall understanding of heat flow which affects the heat penetration into the coal cake. The study confirms that 60% heat was utilized during coking.

  9. Vanadium Geochemistry of Oil Sands Fluid Petroleum Coke.

    Science.gov (United States)

    Nesbitt, Jake A; Lindsay, Matthew B J

    2017-03-07

    Vanadium has previously been linked to elevated toxicity of leachates derived from oil sands petroleum coke. However, geochemical controls on V mobility within coke deposits remain poorly constrained. Detailed examinations of porewater and solid-phase V geochemistry were therefore performed on oil sands fluid petroleum coke deposits in Alberta, Canada. Sample collection focused on both active and reclaimed deposits, which contained more than 3 × 10(7) m(3) of fluid petroleum coke. Dissolved V concentrations were highest (up to 3.0 mg L(-1)) immediately below the water table but decreased rapidly with increasing depth. This trend corresponded to a transition from mildly acidic (pH 6-7) and oxic conditions to mildly alkaline (pH 7-8.5) and anoxic conditions. Scanning electron microscopy (SEM), electron microprobe analysis (EMPA), and micro-X-ray fluorescence (μXRF) mapping revealed coke particles exhibited an internal structure characterized by successive concentric layers. The outer margins of these layers were characterized by elevated V, Fe, Si, and Al concentrations, indicating the presence of inorganic phases. Micro-X-ray absorption near-edge structure (μXANES) spectroscopy revealed that V speciation was dominated by V(IV) porphyrins except at outer margins of layers, where octahedrally coordinated V(III) was a major component. Minor to trace V(V) was also detected within fluid petroleum coke particles.

  10. Fissure formation in coke. 1: The mechanism of fissuring

    Energy Technology Data Exchange (ETDEWEB)

    D.R. Jenkins; M.R. Mahoney; J.C. Keating [CSIRO Mathematical and Information Sciences, North Ryde, NSW (Australia)

    2010-07-15

    Pilot scale coke oven experiments, in which carbonisation has been arrested after 2 and 4 h, have been used to identify key aspects of the initial formation and propagation of fissuring in coke. The experiments show that the primary fissure network is formed within the first few hours of coking and the fissures propagate towards the centre of the oven as coking progresses. They also show that some of the initially formed fissures stop propagating, thus increasing the effective fissure spacing as coking continues. A model for the propagation of regular crack arrays has been used to identify the cause of the initial formation of the fissure network, evaluate the fissure spacing and explain the fissure coarsening effect. The coarsening is shown to be due to an instability, in the form of every second fissure stopping. The formation of lateral fissures is shown to be due to tensile stress formation near the tips of stopped fissures and also to increased shrinkage due to a maximum in the coke contraction coefficient at around 700{sup o}C. 45 refs., 11 figs., 1 tab.

  11. Dry PMR-15 Resin Powders

    Science.gov (United States)

    Vannucci, Raymond D.; Roberts, Gary D.

    1988-01-01

    Shelf lives of PMR-15 polymides lengthened. Procedure involves quenching of monomer reactions by vacuum drying of PRM-15 resin solutions at 70 to 90 degree F immediately after preparation of solutions. Absence of solvent eliminates formation of higher esters and reduces formation of imides to negligible level. Provides fully-formulated dry PMR-15 resin powder readily dissolvable in solvent at room temperature immediately before use. Resins used in variety of aerospace, aeronautical, and commercial applications.

  12. Holographic Quenches with a Gap

    CERN Document Server

    da Silva, Emilia; Mas, Javier; Serantes, Alexandre

    2016-01-01

    In order to holographically model quenches with a gapped final hamiltonian, we consider a gravity-scalar theory in anti-de Sitter space with an infrared hard wall. We allow a time dependent profile for the scalar field at the wall. This induces an energy exchange between bulk and wall and generates an oscillating scalar pulse. We argue that such backgrounds are the counterpart of quantum revivals in the dual field theory. We perform a qualitative comparison with the quench dynamics of the massive Schwinger model, which has been recently analyzed using tensor network techniques. Agreement is found provided the width of the oscillating scalar pulse is inversely linked to the energy density communicated by the quench. We propose this to be a general feature of holographic quenches.

  13. Holographic quenches with a gap

    Science.gov (United States)

    da Silva, Emilia; Lopez, Esperanza; Mas, Javier; Serantes, Alexandre

    2016-06-01

    In order to holographically model quenches with a gapped final hamiltonian, we consider a gravity-scalar theory in anti-de Sitter space with an infrared hard wall. We allow a time dependent profile for the scalar field at the wall. This induces an energy exchange between bulk and wall and generates an oscillating scalar pulse. We argue that such backgrounds are the counterpart of quantum revivals in the dual field theory. We perform a qualitative comparison with the quench dynamics of the massive Schwinger model, which has been recently analyzed using tensor network techniques. Agreement is found provided the width of the oscillating scalar pulse is inversely linked to the energy density communicated by the quench. We propose this to be a general feature of holographic quenches.

  14. The quenching time scale and quenching rate of galaxies

    CERN Document Server

    Lian, Jianhui; Zhang, Kai; Kong, Xu

    2016-01-01

    The average star formation rate (SFR) in galaxies has been declining since redshift of 2. A fraction of galaxies quench and become quiescent. We constrain two key properties of the quenching process: the quenching time scale and the quenching rate among galaxies. We achieve this by analyzing the galaxy number density profile in NUV-u color space and the distribution in NUV-u v.s. u-i color-color diagram with a simple toy-model framework. We focus on galaxies in three mass bins between 10 to 10 and 10 to 10.6 solar mass. In the NUV-u v.s. u-i color-color diagram, the red u-i galaxies exhibit a different slope from the slope traced by the star-forming galaxies. This angled distribution and the number density profile of galaxies in NUV-u space strongly suggest that the decline of the SFR in galaxies has to accelerate before they turn quiescent. We model this color-color distribution with a two-phase exponential decline star formation history. The models with an e-folding time in the second phase (the quenching p...

  15. Shift From Coke to Coal Using Direct Reduction Method and Challenges

    Institute of Scientific and Technical Information of China (English)

    Okonkwo Paul Chukwuleke; CAI Jiu-ju; Sam Chukwujekwu; XIAO Song

    2009-01-01

    Ironmaking involves the separation of iron ores. It not only represents the first step in steelmaking but also is the most capital-intensive and energy-intensive process in the production of steel. The main route for producing iron for steelmaking is to use the blast furnace, which uses metallurgical coke as the reduetant. Concerns over the limited re-sources, the high cost of eoking coals, and the environmental impacts of eoking and sinter plants have driven steel-makers to develop alternative ironmaking processes that can use non-coking coals to reduce iron ores directly. Since the efficiency and productivity of modern large capacity blast furnaces will be difficult to surpass, blast furnaces will continue to retain their predominant position as the foremost ironmaking process for some time to come. The alterna-tive ironmaking processes are therefore expected to play an increasingly significant role in the iron and steel industry, especially in meeting the needs of small-sized local and regional markets. It is likely that the importance of direct re-duced iron (DRI) and hot metal as sources of virgin iron will continue to increase, especially in the developing coun-tries where steelmaking is, and will be, primarily based on electric arc furnace (EAF) minimills. Consequently, the challenges that are faced by the new technology have to be embraced.

  16. Universality in fast quantum quenches

    CERN Document Server

    Das, Sumit R; Myers, Robert C

    2014-01-01

    We expand on the investigation of the universal scaling properties in the early time behaviour of fast but smooth quantum quenches in a general $d$-dimensional conformal field theory deformed by a relevant operator of dimension $\\Delta$ with a time-dependent coupling. The quench consists of changing the coupling from an initial constant value $\\lambda_1$ by an amount of the order of $\\delta \\lambda$ to some other final value $\\lambda_2$, over a time scale $\\delta t$. In the fast quench limit where $\\delta t$ is smaller than all other length scales in the problem, $ \\delta t \\ll \\lambda_1^{1/(\\Delta-d)}, \\lambda_2^{1/(\\Delta-d)}, \\delta \\lambda^{1/(\\Delta-d)}$, the energy (density) injected into the system scales as $\\delta{\\cal E} \\sim (\\delta \\lambda)^2 (\\delta t)^{d-2\\Delta}$. Similarly, the change in the expectation value of the quenched operator at times earlier than the endpoint of the quench scales as $\\langle {\\cal O}_\\Delta\\rangle \\sim \\delta \\lambda\\, (\\delta t)^{d-2\\Delta}$, with further logarithmic...

  17. Chiral Logs in Quenched QCD

    CERN Document Server

    Dong, S J; Horváth, I; Lee, F X; Liu, K F; Mathur, N; Zhang, J B

    2003-01-01

    The quenched chiral logs are examined on a $16^3 \\times 28$ lattice with Iwasaki gauge action and overlap fermions. The pion decay constant $f_{\\pi}$ is used to set the lattice spacing, $a = 0.200(3)$ fm. With pion mass as low as $\\sim 180 {\\rm MeV}$, we see the quenched chiral logs clearly in $m_{\\pi}^2/m$ and $f_P$, the pseudoscalar decay constant. We analyze the data to determine how low the pion mass needs to be in order for the quenched one-loop chiral perturbation theory ($\\chi$PT) to apply. With the constrained curve fitting, we are able to extract the quenched chiral log parameter $\\delta$ together with the chiral cutoff $\\Lambda_{\\chi}$ and other parameters. Only for $m_{\\pi} \\leq 300 {\\rm MeV}$ do we obtain a consistent and stable fit with a constant $\\delta$ which we determine to be 0.23(2). By comparing to the $12^3 \\times 28$ lattice, we estimate the finite volume effect to be about 1.8% for the smallest pion mass. We also study the quenched non-analytic terms in the nucleon and the $\\rho$ masses...

  18. Modeling the formation of the quench product in municipal solid waste incineration (MSWI) bottom ash.

    Science.gov (United States)

    Inkaew, Kanawut; Saffarzadeh, Amirhomayoun; Shimaoka, Takayuki

    2016-06-01

    This study investigated changes in bottom ash morphology and mineralogy under lab-scale quenching conditions. The main purpose was to clarify the mechanisms behind the formation of the quench product/layer around bottom ash particles. In the experiments, the unquenched bottom ashes were heated to 300°C for 1h, and were quenched by warm water (65°C) with different simulated conditions. After having filtered and dried, the ashes were analyzed by a combination of methodologies namely, particle size distribution analysis, intact particle and thin-section observation, X-ray diffractometry, and scanning electron microscope with energy dispersive X-ray spectroscopy. The results indicated that after quenching, the morphology and mineralogy of the bottom ash changed significantly. The freshly quenched bottom ash was dominated by a quench product that was characterized by amorphous and microcrystalline calcium-silicate-hydrate (CSH) phases. This product also enclosed tiny minerals, glasses, ceramics, metals, and organic materials. The dominant mineral phases produced by quenching process and detected by XRD were calcite, Friedel's salt, hydrocalumite and portlandite. The formation of quench product was controlled by the fine fraction of the bottom ash (particle size ash-water reactions and formation of the quench product in the bottom ash was proposed.

  19. Pretreatment of coking wastewater using anaerobic sequencing batch reactor (ASBR)

    Institute of Scientific and Technical Information of China (English)

    LI Bing; SUN Ying-lan; LI Yu-ying

    2005-01-01

    A laboratory-scale anaerobic sequencing batch reactor (ASBR) was used to pretreat coking wastewater. Inoculated anaerobic granular biomass was acclimated for 225 d to the coking wastewater, and then the biochemical methane potential (BMP)of the coking wastewater in the acclimated granular biomass was measured. At the same time, some fundamental technological factors, such as the filling time and the reacting time ratio (tf/tr), the mixing intensity and the intermittent mixing mode, that affect anaerobic pretreatment of coking wastewater with ASBR, were evaluated through orthogonal tests. The COD removal efficiency reached 38%~50% in the stable operation period with the organic loading rate of 0.37~0.54 kg COD/(m3.d) at the optimum conditions of tf/tr, the mixing intensity and the intermittent mixing mode. In addition, the biodegradability of coking wastewater distinctly increased after the pretreatment using ASBR. At the end of the experiment, the microorganism forms on the granulated sludge in the ASBR were observed using SEM (scanning electron microscope) and fluoroscope. The results showed that the dominant microorganism on the granular sludge was Methanosaeta instead of Methanosarcina dominated on the inoculated sludge.

  20. Disposal of Waste Plastics With Traditional Coking Process

    Institute of Scientific and Technical Information of China (English)

    CAI Jiu-ju; YU Guang-wei; LIAO Hong-qiang; QIAN Kai; ZHAO Pen; HE Ya-bin

    2006-01-01

    A new technology for treating waste plastics (WP) by traditional coking process was introduced. With a thermo-balance and a 10 g atmospheric fixed bed reactor, the thermo-gravimetric behavior and product were studied during co-coking of WP with blended coal. And then, using a coke-oven with capacity of 200 kg, the characteristics of products were assessed. The results showed that there is an overlapping temperature range (200-550 ℃) of decomposition between WP and blended coal, and the pyrolysis synergism index η and synergism strength β proposed could evaluate the synergism between them. 1% of added WP results in the maximum synergism in all series experiments. The increase of added WP decreases the synergism. Tar yield in co-coking is increased with the decrease of water yield for synergism. Moreover, it was also found that the quality indexes of coke, such as M10, M40, CRI and CSR, are degraded with the increase of WP until 4%, though the quality of tar and gas is optimized for WP addition.

  1. Method for determining the coking of different types of pyrolysed hydrocarbon crude

    Energy Technology Data Exchange (ETDEWEB)

    Kirpichnikov, P.A.; Grigorovich, B.A.; Liakumovich, A.G.; Galeeva, E.I.; Trifonov, S.V.; Lobanova, E.E.

    1987-01-01

    An express method has been developed for determining coking and the nature of burnout of coke deposits during pyrolysis of hydrocarbon crude. A new, hitherto unknown effect of non-uniform burnout of the carbon deposits (coke) formed during pyrolysis of hydrocarbons has been established. Although the air pulse selected is sufficient to burn out the entire quantity of coke, it is not burnt out uniformly from pulse to pulse, but spasmodically, creating an individual characteristic of the burnout capacity of coke formed during pyrolysis of individual hydrocarbon fractions. The opportunities provided by the method in studying additives that inhibit coke deposition, the rate of formation and burnout of coke in different temperature zones of the pyrolysis coil, and also the nature of burnout of coke formed during pyrolysis of individual hydrocarbons and their mixtures can be broadened significantly, 7 references, 2 figures.

  2. Industrial Experiment on Coke Spraying With ZBS Additive in Blast Furnace

    Institute of Scientific and Technical Information of China (English)

    ZHU Zi-zong; ZHANG Zhu-ming; TANG Qi-yong; YANG Xue-feng; ZHANG Kun-hua; ZHAO Xian-sheng

    2006-01-01

    In order to improve the thermal properties of coke, an industrial experiment on the coke spraying with ZBS additive solution was carried out at coking plant and No.6 blast furnace (2 000 m3) of Kunming Iron and Steel Co Ltd. The coke reaction index (CRI) of the coke spraying with ZBS additive solution decreases by 10.56%, and the coke strength after reaction (CSR) increases by 7.80% in comparison with those of the un-sprayed coke. During the experiment, the average iron output increases by 66.69 t/d, and the coke rate is reduced by 5.21 kg per ton iron, while the fluctuation of furnace temperture is small, and sulphur content in hot metal and 100% of hot metal are acceptable.

  3. Quenching in coupled adiabatic coils

    Energy Technology Data Exchange (ETDEWEB)

    Williams, J.E.C.

    1985-03-01

    The prediction of the effects of a quench on stress and temperature is an important aspect of the design of superconducting magnets. Of particular interest, and the exclusive topic of this study, is the prediction of the effects of quenching in coupled adiabatic coils, such as the multi-section windings of a high field NMR spectrometer magnet. The predictive methods used here are based on the measurement of the time of propagation of quench between turns. From this measurement an approximate algorithum for the propagation time is used in a code which solves the linear differential equations for the coil currents and calculates the movement of normal zone boundaries and hence the associated winding resistance.

  4. Recent trends in the cokemaking of the Ukraine in view of global coke market problems

    Energy Technology Data Exchange (ETDEWEB)

    Rudyka, V. [Giprokoks Institute, Kharkov (Ukraine)

    2004-07-01

    The presentation describes the coke making industry in the Ukraine and other CIS countries (Russia, Kazakhstan, and Georgia). The production and export of coke from the Ukraine has recently increased. The restraining factor will be the supply of domestic coking coal. There are plans for new coke oven batteries and introduction of new technologies. The 12-page text is accompanied by a set of 7 slides/overheads. 6 refs., 3 tabs.

  5. Thermal treatment of a coal blend for coking in a test facility of the Donetsk Coking Plant

    Energy Technology Data Exchange (ETDEWEB)

    Zbykovskii, E.I.; Novitskii, P.L.; Logvinov, A.V.; Shuster, Yu.D.; Golomanskii, N.A.; Kharasik, V.V.; Turik, I.A.; Nekhaenko, V.Ya.

    1986-12-01

    Design and operation are discussed for an experimental facility for heat treatment of coal mixtures for coking used in the Donetsk Coking Plant. The mixture consisted of 80% type G coal and 20% type Zh coal. The treatment system developed jointly by the Donetsk Plant and the Donetsk Technical Institute combined advantages of rotary dryers and fluidized-bed dryers. The dryer consisted of 2 parts: a pipe dryer with a temperature to 100-120 C and a long fluidized-bed chamber (relation of length to width 25 to 1) with a temperature of 200-250 C. Such a configuration of 2 temperature zones prevented deterioration of caking coal properties (which occurred in other heat treatment systems with a final temperature of 200-250 C). Properties of coal mixtures which after preheating in the experimental system were coked under standard conditions, as well as coke properties, are shown in 3 tables. Use of heat treatments increased coke compression strength and reduced its wear index. 3 refs.

  6. Microporous Cokes Formed in Zeolite Catalysts Enable Efficient Solar Evaporation

    KAUST Repository

    Wang, Jianjian

    2017-03-13

    Cokes are inevitably generated during zeolite-catalyzed reactions as deleterious side products that deactivate the catalyst. In this study, we in-situ converted cokes into carbons within the confined microporous zeolite structures and evaluated their performances as absorbing materials for solar-driven water evaporation. With a properly chosen zeolite, the cokederived carbons possessed ordered interconnected pores and tunable compositions. We found that the porous structure and the oxygen content in as-prepared carbons had important influences on their energy conversion efficiencies. Among various investigated carbon materials, the carbon derived from the methanol-to-olefins reaction over zeolite Beta gave the highest conversion efficiency of 72% under simulated sunlight with equivalent solar intensity of 2 suns. This study not only demonstrates the great potential of traditionally useless cokes for solar thermal applications but also provides new insights into the design of carbon-based absorbing materials for efficient solar evaporation.

  7. A method for regulating the temperature of a coke oven

    Energy Technology Data Exchange (ETDEWEB)

    Sibata, M.; Fukava, R.; Khiesi, M.; Omaye, Y.; Terasi, M.

    1983-08-25

    In the proposed method data from measurements of the temperature of the hearth of the heating partitions of the coke oven are received every two hours. The obtained factual data is fed by radio to a computer (EVM) for building the time and temperature curves (VTK) for rating the operational systems and coke oven loading modes. The time and temperature curves are output to displays. When there is a change in the time of the programmed loading modes, the W shaped time and temperature curves are shifted parallel until they aligned with the standard time and temperature curve, while the velocity of the stream of heating gas is regulated in such a way that the heating mode in the coke oven meets the specifications of the standard time and temperature curve.

  8. Interactions between coking coals and plastics during co-pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Richard Sakurovs [CSIRO, North Ryde, NSW (Australia). Division of Energy Technology

    2003-10-01

    Blends of three Australian coking coals and polypropylene, polystyrene, polyacrylonitrile and polyphenylene sulfide were prepared and the extent to which the blends fused on heating was monitored using proton magnetic resonance thermal analysis in order to identify interactions between them that could affect their fluidity. Different plastics had different effects. Polystyrene strongly reduced the fluidity of all of the coals, confirming previous findings. Polypropylene did not affect the fluidity of the two coking coals of lower rank. Polyphenylene sulfide reduced the fluidity of the coals at temperatures near the solidification temperature of the coals, and polyacrylonitrile appeared to increase the fluidity of the coals at temperatures near the softening temperature of the coals. The very different effects different plastics have on coal fluidity show that the interaction between plastics and coals must be carefully examined before plastics are added to coking coal blends. 28 refs., 6 figs., 1 tab.

  9. Textural changes in metallurgical coke prepared with polyethylene

    Institute of Scientific and Technical Information of China (English)

    Stanislav S.Gornostayev; Jyrki J.Heino; Tommi M.T.Kokkonen; Hannu T.Makkonen; Satu M.M.Huttunen; Timo M.J.Fabritius

    2014-01-01

    The effect of high-density polyethylene (HDPE) on the textural features of experimental coke was investigated using polar-ized-light optical microscopy and wavelet-based image analysis. Metallurgical coke samples were prepared in a laboratory-scale furnace with 2.5%, 5.0%, 7.5%, 10.0%, and 12.5%HDPE by mass, and one sample was prepared by 100%coal. The amounts and distribution of textures (isotropic, mosaic and banded) and pores were obtained. The calculations reveal that the addition of HDPE results in a decrease of mosaic texture and an increase of isotropic texture. Ethylene formed from the decomposition of HDPE is considered as a probable reason for the texture modifications. The approach used in this study can be applied to indirect evaluation for the reactivity and strength of coke.

  10. 40 CFR 63.303 - Standards for nonrecovery coke oven batteries.

    Science.gov (United States)

    2010-07-01

    ... batteries. 63.303 Section 63.303 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... National Emission Standards for Coke Oven Batteries § 63.303 Standards for nonrecovery coke oven batteries... existing nonrecovery coke oven battery that exceed any of the following emission limitations...

  11. 40 CFR 63.302 - Standards for by-product coke oven batteries.

    Science.gov (United States)

    2010-07-01

    ... batteries. 63.302 Section 63.302 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... National Emission Standards for Coke Oven Batteries § 63.302 Standards for by-product coke oven batteries... oven emissions from each affected existing by-product coke oven battery that exceed any of...

  12. Optimization of the coke-oven activated sludge plants

    Energy Technology Data Exchange (ETDEWEB)

    Raizer Neto, Ernesto [Santa Catarina Univ., Florianopolis, SC (Brazil); Colin, Francois [Institut de Recherches Hydrologiques, 54 - Nancy (France); Prost, Christian [Laboratoire de Sciences de Genie Chimique, Nancy (France)

    1993-12-31

    In the coke-oven activated sludge plants one of the greatest problems of malfunction is due to inffluent variability. The composition and, or, concentration variations of the inffluent substrate, which can cause an unstable system, are function of the pollutant load. Nevertheless, the knowledge of the kinetic biodegradation of the coke-oven effluent represents the limiting factor to develop an effective biological treatment. This work describes a computational model of the biological treatment which was elaborated and validated from continuous pilot scale experiments and calibrated by comparing its predictions to the pilot experiment`s results. 12 refs., 9 figs., 3 tabs.

  13. Function complex for automated system of coke machinery remote control

    Energy Technology Data Exchange (ETDEWEB)

    Simonov, N.F.; Pankrat' ev, O.N.; Bannikov, L.S.; Slatin, E.I.; Parfenov, G.I.

    1979-05-01

    this paper discusses a functional control system for remote control of coking plants introduced at the KBAiM of the Giprokoks. The control block allows for three modes of operation: fully automatic, by predesignated program according to oven design and technology; semi-automatic, in which individual programs perform automatically, checked and initiated by the operator; and remote, in which the operator controls each operation from the control console. The functions of selecting the location for the coke machinery, signal transmission and control selection have been incorporated as three autonomous but interfacing systems. (In Russian)

  14. Bioanalytical Applications of Fluorenscence Quenching.

    Science.gov (United States)

    1986-02-10

    interaction of different cyclodextrin systems with the polynuclear aromatic compound, pyrene.(7 ) There are other cases where the Stern-Volmer plot deviates... encapsulated in lecithin liposomes. In this manner the fluorescence is self-quenched. When the liposomes are disrupted, the dye is released and

  15. How to quench a galaxy

    Science.gov (United States)

    Pontzen, Andrew; Tremmel, Michael; Roth, Nina; Peiris, Hiranya V.; Saintonge, Amélie; Volonteri, Marta; Quinn, Tom; Governato, Fabio

    2017-02-01

    We show how the interplay between active galactic nuclei (AGNs) and merger history determines whether a galaxy quenches star formation (SF) at high redshift. We first simulate, in a full cosmological context, a galaxy of total dynamical mass Mvir = 1012 M⊙ at z = 2. Then we systematically alter the accretion history of the galaxy by minimally changing the linear overdensity in the initial conditions. This `genetic modification' approach allows the generation of three sets of Λ CDM initial conditions leading to maximum merger ratios of 1:10, 1:5 and 2:3, respectively. The changes leave the final halo mass, large-scale structure and local environment unchanged, providing a controlled numerical experiment. Interaction between the AGN physics and mergers in the three cases leads, respectively, to a star-forming, temporarily quenched and permanently quenched galaxy. However, the differences do not primarily lie in the black hole accretion rates, but in the kinetic effects of the merger: the galaxy is resilient against AGN feedback unless its gaseous disc is first disrupted. Typical accretion rates are comparable in the three cases, falling below 0.1 M⊙ yr-1, equivalent to around 2 per cent of the Eddington rate or 10-3 times the pre-quenching star formation rate, in agreement with observations. This low level of black hole accretion can be sustained even when there is insufficient dense cold gas for SF. Conversely, supernova feedback is too distributed to generate outflows in high-mass systems, and cannot maintain quenching over periods longer than the halo gas cooling time.

  16. Effect of alkaline elements on the reactivity, strength and structural properties of blast furnace cokes

    Directory of Open Access Journals (Sweden)

    A. Bhattacharyya

    2015-07-01

    Full Text Available The present study concerns itself on the adverse effects of alkaline elements like sodium and potassium on blast furnace cokes. To achieve a deeper insight on the effects of alkaline elements on coke reactivity and strength, industrial coke samples impregnated with different alkaline species in various amounts have been tested under standard conditions to find out their Coke Reactivity Index (CRI and Coke Strength after Reaction (CSR values. Scanning electron microscopy, petrographic and Raman Spectrometric investigations demonstrate the change of structural properties. The mechanism of catalysis has been postulated.

  17. Feasibility of Combustion of Petroleum Coke in 230t/h Circulating Fluidized Bed Boiler

    Institute of Scientific and Technical Information of China (English)

    HAN Dong-tai; SONG Zheng-chang; XU Tao

    2003-01-01

    In order to reuse the high sulfur petroleum coke, the waste in chemical industry, as fuel of power plant for energy recovery, the combustion property of petroleum coke was researched experimentally in circulating fluidized bed (CFB) boiler. The performance of the boiler in burning mixed fuel with different ratios of coal to petroleum coke is obtained. Based on the experimental data, Factors influencing the stability of combustion,thermal efficiency of boiler, and emissions and desulphurisation are discussed. This study demonstrates that the combustion of petroleum coke in CFB boiler is applicable, and has great significance on the design and operation of CFB boiler to burn petroleum coke.

  18. The effect of blast furnace coke quality on the possibility of its use

    Directory of Open Access Journals (Sweden)

    A. Konstanciak

    2013-04-01

    Full Text Available In the paper behavior of the blast-furnace coke in the high temperature was presented. Comparative analysis of the chemical composition of the blast-furnace coke and the heat treatment of it were done. Coefficients M10 and M40 with the thermo-abrasiveness for chosen cokes were compared. The influence of ash content of the coke on the blast-furnace bed permeability was defined. Usefulness of the coke to blast-furnace process was also defined.

  19. Application research on hydraulic coke cutting monitoring system based on optical fiber sensing technology

    Science.gov (United States)

    Zhong, Dong; Tong, Xinglin

    2014-06-01

    With the development of the optical fiber sensing technology, the acoustic emission sensor has become one of the focal research topics. On the basis of studying the traditional hydraulic coke cutting monitoring system, the optical fiber acoustic emission sensor has been applied in the hydraulic coke cutting monitoring system for the first time, researching the monitoring signal of the optical fiber acoustic emission sensor in the system. The actual test results show that using the acoustic emission sensor in the hydraulic coke cutting monitoring system can get the real-time and accurate hydraulic coke cutting state and the effective realization of hydraulic coke cutting automatic monitoring in the Wuhan Branch of Sinopec.

  20. Quench Simulation Studies: Program documentation of SPQR

    CERN Document Server

    Sonnemann, F

    2001-01-01

    Quench experiments are being performed on prototypes of the superconducting magnets and busbars to determine the adequate design and protection. Many tests can only be understood correctly with the help of quench simulations that model the thermo-hydraulic and electrodynamic processes during a quench. In some cases simulations are the only method to scale the experimental results of prototype measurements to match the situation of quenching superconducting elements in the LHC. This note introduces the theoretical quench model and the use of the simulation program SPQR (Simulation Program for Quench Research), which has been developed to compute the quench process in superconducting magnets and busbars. The model approximates the heat balance equation with the finite difference method including the temperature dependence of the material parameters. SPQR allows the simulation of longitudinal quench propagation along a superconducting cable, the transverse propagation between adjacent conductors, heat transfer i...

  1. The history of a unique South Wales coking plant

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, P.

    2006-07-01

    During 1914 the Coppee Company was contracted to build two batteries of 30 coke ovens, a washery and by-product plant at Coed Ely in the Ely Valley, South Wales, near to a productive colliery. The coal was formed into a cake by stamping it into a mould slightly smaller than the oven. Straw was used as a binder. The coke produced was ideal for iron making. The article describes the stamp charging process, the cooling process, and the by-product plant producing a 'tar oil winter wash' (ammonium sulphateude benzol and coal gas). It describes the construction and later extensions of the batteries. It recounts the history of the rail system linking the coking plant and the mine and has illustrated descriptions of Locomotive Coedely, Locomotive Ferndale, Locomotive Tynycoed and Locomotive Austerity 0-6-OST. The coking works was finally closed in October 1983, following the 1979 change of government which shut the industry from all sides. Today the hillside is landscaped and grass is beginning to grow where the works once was. This article was fist published in the Archive Magazine, No. 41, of March 2004, pp 3-26. 25 figs.

  2. Practical aspects of coking in Cundinamarca y Boyacá

    Directory of Open Access Journals (Sweden)

    Segundo Manuel Romero-Balaguera

    2014-12-01

    Full Text Available Taking advantage of the excellent qualities of the studied coals from the coalfields in Cundinamarca and terms of the types of coking ovens, for excellent performance and quality that allows them to be very competitive.The international market is very demanding in terms of the quality of coke and CRI and CSR indexes, that is why coals laboratories were implemented and improved the system of sampling and analysis of laboratories for more agile and modern. Mixtures were made with the test methodology and empirical methods combining swelling index and rank cals were the theree main types: high, medium and low volatile. But with studies and techological change and enviromental control, process is managed, allowing the coke industry to serve as a development center for the promotion of industries in the central area of this country. In the study the whole process is presented beginning with the explotaitation of coking coals, the care that must be taken into account to mainttain good quality, transport and enviromental measures, the process of crushing and grinding to prepare the optimal mix and laboratory tests necessary to maintain quality control, the types of ovens in Boyacá Colombia, yields and advances in the se technologies, and finally, the system shutdown process. All of the above was addressed in order to add value to the product with the fulfillment of the international market standards.

  3. Coke Reactivity in Simulated Blast Furnace Shaft Conditions

    Science.gov (United States)

    Haapakangas, Juho; Suopajärvi, Hannu; Iljana, Mikko; Kemppainen, Antti; Mattila, Olli; Heikkinen, Eetu-Pekka; Samuelsson, Caisa; Fabritius, Timo

    2016-08-01

    Despite the fact that H2 and H2O are always present in the gas atmosphere of a blast furnace shaft, their role in the solution-loss reactions of coke has not been thoroughly examined. This study focuses on how H2 and H2O affect the reaction behavior and whether a strong correlation can be found between reactivity in the conditions of the CRI test (Coke Reactivity Index) and various simulated blast furnace shaft gas atmospheres. Partial replacement of CO/CO2 with H2/H2O was found to significantly increase the reactivity of all seven coke grades at 1373 K (1100 °C). H2 and H2O, however, did not have a significant effect on the threshold temperature of gasification. The reactivity increasing effect was found to be temperature dependent and clearly at its highest at 1373 K (1100 °C). Mathematical models were used to calculate activation energies for the gasification, which were notably lower for H2O gasification compared to CO2 indicating the higher reactivity of H2O. The reactivity results in gas atmospheres with CO2 as the sole gasifying component did not directly correlate with reactivity results in gases also including H2O, which suggests that the widely used CRI test is not entirely accurate for estimating coke reactivity in the blast furnace.

  4. Co-gasification of oil sand coke with coal

    Energy Technology Data Exchange (ETDEWEB)

    Vejahati, Farshid; Gupta, Rajender [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

    2013-07-01

    Gasification of oil sand delayed coke with sub-bituminous and lignite coals was performed in an atmospheric entrained flow gasifier using steam and oxygen as gasifying agents. The underlying objective of this work was to assess the effects of the operating variables (i.e. temperature, oxygen and steam concentrations) and coal/coke blending ratio on gasification performance in a high-temperature in order to find the possible synergies in co-gasification of the fuels. Experiments were conducted at 1,400 C, using steam and oxygen to carbon weight ratios of (0.36-1.08) and (0.07-0.2), respectively in N{sub 2} carrier gas. The coke to coal weight ratios of 1/3, 1/2, and 2/3 were used for the blending tests. Particle size of 53-90 {mu}m with d{sub 50} = 75 {mu}m were used. In terms of char reactivity, blending did not show any significant positive effect. Slight deviations from linear additive line are in the order of experiment error. Gasification efficiency was also following a linear additive trend once more pointing out the lack of synergy in entrained flow gasification systems. The results however, showed that higher coke content clearly favored the H{sub 2} production.

  5. Oil sand process-affected water treatment using coke adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Gamal El-Din, M.; Pourrezaei, P.; Chelme-Ayala, P.; Zubot, W. [Alberta Univ., Edmonton, AB (Canada). Dept. of Civil and Environmental Engineering

    2010-07-01

    Oil sands operations generate an array of oil sands process-affected water (OSPW) that will eventually be released to the environment. This water must be evaluated within conventional and advanced water treatment technologies. Water management strategies propose options for increased reuse and recycling of water from settling ponds, as well as safe discharge. This presentation outlined the typical composition of OSPW. Constituents of concern in OSPW include suspended solids, hydrocarbons, salts, ammonia, trace metals, and dissolved organics such as naphthenic acids (NAs). Petroleum coke is one of the by-products generated from bitumen extraction in the oil sands industry and can be used as one of the possible treatment processes for the removal of organic compounds found in OSPW. Activated carbon adsorption is an effective process, able to adsorb organic substances such as oils, radioactive compounds, petroleum hydrocarbons, poly aromatic hydrocarbons and various halogenated compounds. The objectives of this study were to evaluate the production of activated carbon from petroleum coke using steam as the activation media; to determine the factors affecting the absorption of NAs; and to evaluate the activated coke adsorption capacity for the reduction of NAs and dissolved organic carbons present in OSPW. It was concluded that petroleum non-activated coke has the ability to decrease COD, alkalinity, and NA concentration. tabs., figs.

  6. 29 CFR 1910.1029 - Coke oven emissions.

    Science.gov (United States)

    2010-07-01

    ... Data Exposure to coke oven emissions is a cause of lung cancer, and kidney cancer, in humans. Although... to which other Federal agencies exercise statutory authority to prescribe or enforce standards... status of the program. (7) Training in compliance procedures. The employer shall incorporate all...

  7. Thickness Optimization for Petroleum Coke in Microwave Dehydrating Based on the Analysis of Dynamic Absorption Efficiency

    Science.gov (United States)

    Shang, Xiaobiao; Chen, Junruo; Peng, Jinhui; Chen, Hua; Zhang, Weifeng; Guo, Shenghui; Chen, Guo

    2015-07-01

    An analytical approach is proposed to optimize the thickness of petroleum coke for achieving maximum microwave power absorption in microwave heating based on analysis of reflection loss (RL). The microwave RL of the petroleum coke layer was studied over the moisture content range of 1%-5% at 20 °C and the petroleum coke (10% moisture content) in the temperature range of 20 to 100 °C at 2.45 GHz. The results show that RL depends sensitively on the thickness of the petroleum coke and the absorption peak shifts towards a larger thickness as the moisture content of the petroleum coke increases. There exists a matching thickness corresponding to the maximum microwave absorption, the maximum absorbing peak decreases when the thickness of petroleum coke exceeds the matching thickness. We also show that the absorption peak is found to move towards a smaller thickness region with increasing petroleum coke temperature.

  8. Measurement of Vibrated Bulk Density of Coke Particle Blends Using Image Texture Analysis

    Science.gov (United States)

    Azari, Kamran; Bogoya-Forero, Wilinthon; Duchesne, Carl; Tessier, Jayson

    2017-09-01

    A rapid and nondestructive machine vision sensor was developed for predicting the vibrated bulk density (VBD) of petroleum coke particles based on image texture analysis. It could be used for making corrective adjustments to a paste plant operation to reduce green anode variability (e.g., changes in binder demand). Wavelet texture analysis (WTA) and gray level co-occurrence matrix (GLCM) algorithms were used jointly for extracting the surface textural features of coke aggregates from images. These were correlated with the VBD using partial least-squares (PLS) regression. Coke samples of several sizes and from different sources were used to test the sensor. Variations in the coke surface texture introduced by coke size and source allowed for making good predictions of the VBD of individual coke samples and mixtures of them (blends involving two sources and different sizes). Promising results were also obtained for coke blends collected from an industrial-baked carbon anode manufacturer.

  9. Quenched Reinforcement Exposed to Fire

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl

    2006-01-01

    Idealized data are derived for the tensile strength of quenched and tempered prestressing steel and of quenched and self-tempered reinforcing bars for fire safety design. 0.2% stresses are derived as a function of the maximum temperature and in addition, 2.0% stresses are provided. A strain of 2.......0% is seldom found in “slack” (not prestressed) reinforcement, but 2.0% stresses might be relevant for reinforcement in T shaped cross sections and for prestressed structures, where large strains can be applied. All data are provided in a “HOT” condition during a fire and in a “COLD” condition after a fire....... The COLD condition is relevant for analyses of residual load bearing capacity of a structure after a fire exposure. It is also relevant for analyses of concrete structures exposed to fully developed fire courses. The reason is that compression zones of concrete are always the weakest in the cooling phase...

  10. Holographic quenches and anomalous transport

    CERN Document Server

    Ammon, Martin; Jimenez-Alba, Amadeo; Macedo, Rodrigo P; Melgar, Luis

    2016-01-01

    We study the response of the chiral magnetic effect due to continuous quenches induced by time dependent electric fields within holography. Concretely, we consider a holographic model with dual chiral anomaly and compute the electric current parallel to a constant, homogeneous magnetic field and a time dependent electric field in the probe approximation. We explicitly solve the PDEs by means of pseudospectral methods in spatial and time directions and study the transition to an universal "fast" quench response. Moreover, we compute the amplitudes, i.e.,~residues of the quasi normal modes, by solving the (ODE) Laplace transformed equations. We investigate the possibility of considering the asymptotic growth rate of the amplitudes as a well defined notion of initial time scale for linearized systems. Finally, we highlight the existence of Landau level resonances in the electrical conductivity parallel to a magnetic field at finite frequency and show explicitly that these only appear in presence of the anomaly. ...

  11. Quench cooling under reduced gravity

    CERN Document Server

    Chatain, D; Nikolayev, V S; Beysens, D

    2013-01-01

    We report the quench cooling experiments performed with liquid O2 under different levels of gravity simulated with the magnetic gravity compensation. A copper disk is quenched from 270K to 90K. It is found that the cooling time in microgravity is very long in comparison with any other gravity level. This phenomenon is explained by the isolation effect of the gas surrounding the disk. The liquid subcooling is shown to drastically improuve the heat exchange thus reducing the cooling time (about 20 times). The effect of subcooling on the heat transfer is analyzed at different gravity levels. It is shown that such type of experiments cannot be used for the analysis of the critical heat flux (CHF) of the boiling crisis. The minimum heat flux (MHF) of boiling is analyzed instead.

  12. Quenched Reinforcement Exposed to Fire

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl

    2006-01-01

    Idealized data are derived for the tensile strength of quenched and tempered prestressing steel and of quenched and self-tempered reinforcing bars for fire safety design. 0.2% stresses are derived as a function of the maximum temperature and in addition, 2.0% stresses are provided. A strain of 2.......0% is seldom found in “slack” (not prestressed) reinforcement, but 2.0% stresses might be relevant for reinforcement in T shaped cross sections and for prestressed structures, where large strains can be applied. All data are provided in a “HOT” condition during a fire and in a “COLD” condition after a fire....... The COLD condition is relevant for analyses of residual load bearing capacity of a structure after a fire exposure. It is also relevant for analyses of concrete structures exposed to fully developed fire courses. The reason is that compression zones of concrete are always the weakest in the cooling phase...

  13. Startup and initial operation of a DFGD and pulse jet fabric filter system on Cokenergy's Indiana Harbor coke oven off gas system

    Energy Technology Data Exchange (ETDEWEB)

    Morris, W.J.; Gansley, R.R.; Schaddell, J.G.

    1999-07-01

    This paper describes the design, initial operation and performance testing of a Dry Flue Gas Desulfurization (DFGD) and Modular Pulse Jet Fabric Filter (MPJFF) system installed at Cokenergy's site in East Chicago, Indiana. The combined flue gas from the sixteen (16) waste heat recovery boilers is processed by the system to control emissions of sulfur dioxide and particulates. These boilers recover energy from coke oven off gas from Indiana Harbor Coke Company's coke batteries. The DFGD system consists of two 100% capacity absorbers. Each absorber vessel uses a single direct drive rotary atomizer to disperse the lime slurry for SO{sub 2} control. The MPJFF consists of thirty two (32) modules arranged in twin sixteen-compartment (16) units. The initial start up of the DFGD/MPJFF posed special operational issues due to the low initial gas flows through the system as the four coke oven batteries were cured and put in service for the first time. This occurred at approximately monthly intervals beginning in March 1998. A plan was implemented to perform a staged startup of the DFGD and MPJFF to coincide with the staged start up of the coke batteries and waste heat boilers. Operational issues that are currently being addressed include reliability of byproduct removal. Performance testing was conducted in August and September 1998 at the inlet of the system and the outlet stack. During these tests, particulate, SO{sub 2}, SO{sub 3}, and HCI emissions were measured simultaneously at the common DFGD inlet duct and the outlet stack. Measurements were also taken for average lime, water, and power consumption during the tests as well as system pressure losses. These results showed that all guarantee parameters were achieved during the test periods. The initial operation and performance testing are described in this paper.

  14. Jet-quenching and correlations

    Indian Academy of Sciences (India)

    Fuqiang Wang

    2015-05-01

    This article reviews recent advances in our understanding of the experimental aspects of jet-quenching and correlations in relativistic heavy-ion collisions at RHIC and LHC. Emphasis is put on correlation measurements, namely jet-like correlations with anisotropic flow subtraction in heavy-ion collisions and long-range pseudorapidity correlations in small systems. Future path on correlation studies is envisioned which may elucidate jet–medium interactions and the properties of the hot dense medium in QCD.

  15. The LHC quench protection system

    CERN Multimedia

    2009-01-01

    The new quench protection system (QPS) has the crucial roles of providing an early warning for any part of the superconducting coils and busbars that develop high resistance, as well as triggering the switch-off of the machine. Over 2000 new detectors will be installed around the LHC to make sure every busbar segment between magnets is monitored and protected. One of the major consolidation activities for the LHC is the addition of two new detectors to the quench protection system. A magnet quench occurs when part of the superconducting cable becomes normally-conducting. When the protection system detects an increased resistance the huge amount of energy stored in the magnet chains is safely extracted and ‘dumped’ into specially designed resistors. In the case of the main dipole chain, the stored energy in a single LHC sector is roughly the same as the kinetic energy of a passenger jet at cruising speed. The first new detector is designed to monitor the superconducting...

  16. How to quench a galaxy

    CERN Document Server

    Pontzen, Andrew; Roth, Nina; Peiris, Hiranya V; Saintonge, Amélie; Volonteri, Marta; Quinn, Tom; Governato, Fabio

    2016-01-01

    We show how the interplay between active galactic nuclei (AGN) and merger history determines whether a galaxy quenches star formation at high redshift. We first simulate, in a full cosmological context, a galaxy of total dynamical mass $10^{12}\\,M_{\\odot}$ at $z=2$. Then we systematically alter the accretion history of the galaxy by minimally changing the linear overdensity in the initial conditions. This "genetic modification" approach allows the generation of three sets of $\\Lambda$CDM initial conditions leading to maximum merger ratios of 1:10, 1:5 and 2:3 respectively. The changes leave the final halo mass, large scale structure and local environment unchanged, providing a controlled numerical experiment. Interaction between the AGN physics and mergers in the three cases lead respectively to a star-forming, temporarily-quenched and permanently-quenched galaxy. However the differences do not primarily lie in the black hole accretion rates, but in the kinetic effects of the merger: the galaxy is resilient a...

  17. Quantum quench and scaling of entanglement entropy

    Science.gov (United States)

    Caputa, Paweł; Das, Sumit R.; Nozaki, Masahiro; Tomiya, Akio

    2017-09-01

    Global quantum quench with a finite quench rate which crosses critical points is known to lead to universal scaling of correlation functions as functions of the quench rate. In this work, we explore scaling properties of the entanglement entropy of a subsystem in a harmonic chain during a mass quench which asymptotes to finite constant values at early and late times and for which the dynamics is exactly solvable. When the initial state is the ground state, we find that for large enough subsystem sizes the entanglement entropy becomes independent of size. This is consistent with Kibble-Zurek scaling for slow quenches, and with recently discussed ;fast quench scaling; for quenches fast compared to physical scales, but slow compared to UV cutoff scales.

  18. Quenching star formation in cluster galaxies

    CERN Document Server

    Taranu, Dan S; Balogh, Michael L; Smith, Russell J; Power, Chris; Krane, Brad

    2012-01-01

    In order to understand the processes that quench star formation within rich clusters, we construct a library of subhalo orbits drawn from lambdaCDM cosmological N-body simulations of four rich clusters. The orbits are combined with models of star formation followed by quenching in the cluster environment to predict colours and spectroscopic line indices of satellite galaxies. Simple models with only halo mass-dependent quenching and without environmental (i.e. cluster-dependent) quenching fail to reproduce the observed cluster-centric colour and absorption linestrength gradients. Models in which star formation is instantly quenched at the virial radius also fail to match the observations. Better matches to the data are achieved by more complicated bulge-disc models in which the bulge stellar populations depend only on the galaxy subhalo mass while the disc quenching depends on the cluster environment. In the most successful models quenching begins at pericentre, operating on an exponential timescale of 2 -- 3...

  19. Pitches thermal conversion study in mesophases and cokes, carbon and graphite materials precursors; Estudo da conversao termica de piches em mesofases e coques, precursores de materiais carbonosos e grafiticos

    Energy Technology Data Exchange (ETDEWEB)

    Otani, Satika

    1991-07-01

    The physical chemistry properties of cokes obtained from pitches are strongly influenced by precursor pitch chemistry and by heat treatment conditions. In the present work, the correlations among heat treatment conditions, such as sample folder materials, heating rate, maximum temperature and quenching temperature, were firstly established, based in 110 coal tar pitch produced by Asfaltos Vitoria Ltda. Then, representative pitches produced by brazilian manufacturers were heat treated under previously fixed conditions by earlier experiments. The physical chemistry characterization of cokes and mesophase obtained from different pitches enable to classify them in groups according to the potentiality of each pitch. It was also shown the results of two stage heat treatment (high pressure and vacuum) study done on coal tar pitch, comparatively to the decanted oil and ethylen tar pitch to investigate the formed mesophase. (author)

  20. Granulation of coke breeze fine for using in the sintering process

    Directory of Open Access Journals (Sweden)

    Mohamed F.M.

    2010-01-01

    Full Text Available Coke breeze is the main fuel used in the sintering process. The value of -3+1 mm. represents the most favorable particle size for coke breeze in the sintering process. About 20% of total coke fines (-0.5 mm are produced during different steps of preparation. Introducing these fines during the sintering process proves to be very harmful for different operating parameters. Thus ,this study aims at investigating the production of granules resulting from these fines using molasses as organic binder and its application in sintering of an iron ore. The results showed that the granules having the highest mechanical properties were obtained with 14.5 wt % molasses addition. The sintering experiments were performed by using coke breeze in different shapes (-3+1 mm in size, coke breeze without sieving and coke breeze granules -3+1 mm. The reduction experiments, microscopic structure and X-ray analysis for the produced sinter were carried out. The results revealed that, all sinter properties (such as shatter test, productivity of sinter machine and blast furnace, reduction time and chemical composition for produced sinter by using coke breeze with size -3+1 mm and coke breeze granules were almost the same. The iron ore sinter which was produced by using coke breeze without sieving yielded low productivity for both sinter machine and blast furnace. Furthermore, using coke breeze without sieving in sintering of an iron ore decreases the vertical velocity of sinter machine and increases the reduction time.

  1. Comparative study of reactivity to CO{sub 2} of cokes used in stone wool production

    Energy Technology Data Exchange (ETDEWEB)

    Leth-Miller, R.; Jensen, L.M.; Hansen, P.B. [Rockwool International A/S Hovedgaden 584, DK 2640, Hedehusene (Denmark); Jensen, A.D.; Jensen, J.; Glarborg, P.; Joergensen, S.B. [Department of Chemical Engineering, Technical University of Denmark, 2800 Kgs. Lyngby (Denmark)

    2005-02-25

    The reactivity towards CO{sub 2} of seven types of commercial coke used in stone wool production has been measured in a thermo gravimetric analyser (TGA). The cokes originated from Western and Eastern Europe and from China. For three of the cokes, the porosity, density and surface area were determined. The directly measured porosities of the cokes was slightly low, indicating that there are pores that are not connected with the outer surface. This is supported by the measured densities and microphotos. The measurements showed that the Chinese cokes were the least reactive while the European cokes made on American coal were the most reactive. The reactivity of the one Eastern European coke in the measurements had an intermediate reactivity. Simulations with a cupola model show that 25% more coke is needed for stone wool production if the coke is changed to a type with half the reactivity towards O{sub 2} and CO{sub 2}. The TGA method proved to be a good method for ranking the coke with respect to reactivity with CO{sub 2}.

  2. Emissions of polycyclic aromatic hydrocarbons from coking industries in China

    Institute of Scientific and Technical Information of China (English)

    Ling Mu; Lin Peng; Junji Cao; Qiusheng He; Fan Li; Jianqiang Zhang; Xiaofeng Liu

    2013-01-01

    This study set out to assess the characteristics of polycyclic aromatic hydrocarbon (PAH) emission from coking industries,with field samplings conducted at four typical coke plants.For each selected plant,stack flue gas samples were collected during processes that included charging coal into the ovens (CC),pushing coke (PC) and the combustion of coke-oven gas (CG).Sixteen individual PAHs on the US EPA priority list were analyzed by gas chromatography/mass spectrometry (GC/MS).Results showed that the total PAH concentrations in the flue gas ranged from 45.776 to 414.874 μg/m3,with the highest emission level for CC (359.545 μg/m3).The concentration of PAH emitted from the CC process in CP1 (stamp charging) was lower than that from CP3 and CP4 (top charging).Low-molecular-weight PAHs (i.e.,two-to three-ring PAHs) were predominant contributors to the total PAH contents,and Nap,AcPy,Flu,PhA,and AnT were found to be the most abundant ones.Total BaPeq concentrations for CC (2.248 iμg/m3) were higher than those for PC (1.838 μg/m3) and CG (1.082 μg/m3),and DbA was an important contributor to carcinogenic risk as BaP in emissions from coking processes.Particulate PAH accounted for more than 20% of the total BaPeq concentrations,which were significantly higher than the corresponding contributions to the total PAH mass concentration (5%).Both particulate and gaseous PAH should be taken into consideration when the potential toxicity risk of PAH pollution during coking processes is assessed.The mean total-PAH emission factors were 346.132 and 93.173 μg/kg for CC and PC,respectively.

  3. Research about the Impact of Coke Thermal Performance When Distributing Australian Coke%配入澳煤对焦炭热性能的影响

    Institute of Scientific and Technical Information of China (English)

    张明远; 纪长洋; 万红兵; 蒋成

    2012-01-01

    The impact of coke thermal performance when distributing Australian coke can be researched, according to existing coking coal blending coal plant chongqing small coke oven blending test,coke thermal performance test, coke microcrystalline structure experiment.The results show that different blending option, coke microcrystalline structure and thermal properties are different.If increase the quantity of the Macao coal, in the little change of the thermal properties of coke, the production cost can be reduced greatly.%通过对重钢焦化厂焦化配煤煤种进行特性检测,小焦炉配煤试验,焦炭热性能检测试验及焦炭微晶结构分析,研究澳媒对焦炭热性能的影响。结果表明,澳煤的技术指标接近焦煤,在配煤方案中可代替部分肥煤或焦煤。配入20%左右的澳煤,相应降低肥煤和焦煤配入比例所得到的焦炭其热性能较稳定。

  4. Anti-corrosion paint and varnish coatings employing wastes from coke and coal chemicals production

    Energy Technology Data Exchange (ETDEWEB)

    L.B. Pavlovich; N.M. Alekseeva; V.P. Dolgopolov; A.A. Popov [West Siberian Metallurgical Combine, Siberia (Russian Federation)

    2004-06-01

    The various shops of the West Siberian Metallurgical Combine operate 392 gas-cleaning units, and the combine annually spends 1.5 million rubles a year on major repairs to this equipment. The need to increase the service life of the air ducts is obvious. At the same time, the production of phthalic anhydride (PA) from commercial grades of naphthalene made at coke and coal chemicals plants also yields large quantities of waste products formed in oxidation reactions - still residues from the distillation of PA. These residues are currently used in coking charges. It is important that a way be found to recycle wastes from the production of phthalic anhydride, which is the main raw material used to make corrosion-resistant paints and lacquers. The goal of the research was to use PA production wastes to help develop promising new environmentally clean materials to protect metal from corrosion. The Combine has developed and mastered the production of two types of powdered polymer-based paint: quick-drying epoxide paint PEFAN-501; decorative epoxide-polyester paint NOVOLAN-1605. A section to make these paints has been set up and equipped with three units that apply the paints in an electrostatic field. The Combine has also developed a technology for using PA still residues to obtain an alkyl-epoxide primer for protecting gas pipes from corrosion. Experimental batches of the primer have been successfully tested on a section of gas pipe connected to the car dumper in the crushing-sorting plant operated by the sinter-lime department.

  5. Jet quenching via jet collimation

    CERN Document Server

    Casalderrey-Solana, J; Wiedemann, U

    2011-01-01

    The strong modifications of dijet properties in heavy ion collisions measured by ATLAS and CMS provide important constraints on the dynamical mechanisms underlying jet quenching. In this work, we show that the transport of soft gluons away from the jet cone - jet collimation - can account for the observed dijet asymmetry with values of $\\hat{q}\\, L$ that lie in the expected order of magnitude. Further, we show that the energy loss attained through this mechanism results in a very mild distortion of the azimuthal angle dijet distribution.

  6. Jet Quenching via Jet Collimation

    CERN Document Server

    Casalderrey-Solana, Jorge; Wiedemann, Urs Achim

    2011-01-01

    The ATLAS Collaboration recently reported strong modifications of dijet properties in heavy ion collisions. In this work, we discuss to what extent these first data constrain already the microscopic mechanism underlying jet quenching. Simple kinematic arguments lead us to identify a frequency collimation mechanism via which the medium efficiently trims away the soft components of the jet parton shower. Through this mechanism, the observed dijet asymmetry can be accomodated with values of $\\hat{q}\\, L$ that lie in the expected order of magnitude.

  7. Treatment of coking wastewater by using manganese and magnesium ores.

    Science.gov (United States)

    Chen, Tianhu; Huang, Xiaoming; Pan, Min; Jin, Song; Peng, Suchuan; Fallgren, Paul H

    2009-09-15

    This study investigated a wastewater treatment technique based on natural minerals. A two-step process using manganese (Mn) and magnesium (Mg) containing ores were tested to remove typical contaminants from coking wastewater. Under acidic conditions, a reactor packed with Mn ore demonstrated strong oxidizing capability and destroyed volatile phenols, chemical oxygen demand (COD)(,) and sulfide from the coking wastewater. The effluent was further treated by using Mg ore to remove ammonium-nitrogen and phosphate in the form of magnesium ammonium phosphate (struvite) precipitates. When pH of the wastewater was adjusted to 1.2, the removal efficiencies for COD, volatile phenol and sulfide reached 70%, 99% and 100%, respectively. During the second step of precipitation, up to 94% of ammonium was removed from the aqueous phase, and precipitated in the form of struvite with phosphorus. The struvite crystals showed a needle-like structure. X-ray diffraction and transmission electron microscopy were used to characterize the crystallized products.

  8. Ignition Dynamic Parameters for Coke in Cement Calciners

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The mathematical ignition model was established and researches of ignition dynamic parameters for coke in some typical coal samples from cement plants was carried out according to circumstances of coal combusted in cement plants.In order to get the ignitioin temperature Tpi of carbon particles more accurately,the temperature rising experimental method was used and the actual heating circumstances for pulverized coal in calciners(in cement plants)were also considered.With this method,the accurate determination of the ignition temperature of coke in coal was achieved,so as to get some ignition dynamic parameters.These research results provide a theoretical basis for investigating coal ignition characteristics more scientifically and more accurately.

  9. Integrated coke, asphalt and jet fuel production process and apparatus

    Science.gov (United States)

    Shang, Jer Y.

    1991-01-01

    A process and apparatus for the production of coke, asphalt and jet fuel m a feed of fossil fuels containing volatile carbon compounds therein is disclosed. The process includes the steps of pyrolyzing the feed in an entrained bed pyrolyzing means, separating the volatile pyrolysis products from the solid pyrolysis products removing at least one coke from the solid pyrolysis products, fractionating the volatile pyrolysis products to produce an overhead stream and a bottom stream which is useful as asphalt for road pavement, condensing the overhead stream to produce a condensed liquid fraction and a noncondensable, gaseous fraction, and removing water from the condensed liquid fraction to produce a jet fuel-containing product. The disclosed apparatus is useful for practicing the foregoing process. the process provides a useful method of mass producing and jet fuels from materials such as coal, oil shale and tar sands.

  10. Standard method for proximate analysis of coal and coke

    Energy Technology Data Exchange (ETDEWEB)

    1975-01-01

    ASTM methods are cited that cover the determination of moisture, volatile matter, and ash and the calculation of fixed carbon in coals and cokes sampled and prepared by prescribed methods. The methods cited may be used to establish rank of coals, to show the ratio of combustible to incombustible constituents, to provide the basis for buying and selling, and to evaluate for beneficiation or for other purposes. (BLM)

  11. A method of, and apparatus for cooling and keeping clean the roof of a coke oven

    Energy Technology Data Exchange (ETDEWEB)

    Hoelter, H.; Igelbuescher, H.; Gresch, H.

    1990-01-04

    Coking emissions occurring in the region of a coke oven roof are trapped and controlled at the coke oven roof so that clean conditions are safeguarded. A roof super structure is disposed above a bank of coke ovens to define a chamber in which a partial vacuum prevails. Emissions are dispersed into a chimney in the region of the riser pipes, covering the bank of coke ovens. On the side of the chamber opposite the riser pipes and chimney fresh air is continuously drawn in and blown into the chamber with the aid of nozzles. Thus, air guidance directly at the coke oven roof is favourable, guaranteeing maintenance of admissible workplace temperatures and other environmental conditions.

  12. Wet oxidation of real coke wastewater containing high thiocyanate concentration.

    Science.gov (United States)

    Oulego, Paula; Collado, Sergio; Garrido, Laura; Laca, Adriana; Rendueles, Manuel; Díaz, Mario

    2014-01-01

    Coke wastewaters, in particular those with high thiocyanate concentrations, represent an important environmental problem because of their very low biodegradability. In this work, the treatment by wet oxidation of real coke wastewaters containing concentrations of thiocyanate above 17 mM has been studied in a 1-L semi-batch reactor at temperatures between 453 and 493 K, with total oxygen pressures in the range of 2.0-8.0 MPa. A positive effect of the matrix of real coke wastewater was observed, resulting in faster thiocyanate degradation than was obtained with synthetic wastewaters. Besides, the effect of oxygen concentration and temperature on thiocyanate wet oxidation was more noticeable in real effluents than in synthetic wastewaters containing only thiocyanate. It was also observed that the degree of mineralization of the matrix organic compounds was higher when the initial thiocyanate concentration increased. Taking into account the experimental data, kinetic models were obtained, and a mechanism implying free radicals was proposed for thiocyanate oxidation in the matrix considered. In all cases, sulphate, carbonates and ammonium were identified as the main reaction products of thiocyanate wet oxidation.

  13. An additive for a petroleum coke and water suspension

    Energy Technology Data Exchange (ETDEWEB)

    Khiguti, K.; Igarasi, T.; Isimura, Y.; Kharaguti, S.; Tsudzina, T.

    1983-03-04

    The patent covers an additive for a petroleum coke and watersuspension which contains soap of an aliphatic acid (AM) and or a salt of a maleic acid copolymer (SMK). The aliphatic acid soap is a salt of an alkaline earth metal of C6 to C22 aliphatic acid, an ammonium salt or a salt of a lower amine. The maleic acid copolymer is a salt (sodium, NH4) of a lower amine of a maleic anhydride copolymer with a copolymerizing vinyl additive. Capric acid, lauric acid, palmatic acid, aleic and other acids may be used as the aliphatic acid, while methylamine, trimethylamine, diethanolamine, morpholine and so on may be used as the lower amine salt. Ethylene, vinylchloride, methyl(meta)acrylate and so on are used as the polymerizing vinyl compound. The molar ratio of the maleic anhydride to the polymerizing vinyl compound is in a range from 1 to 1 to 1 to 10 (preferably 1 to 1 to 1 to 3). The maleic acid copolymer has a mean molecular mass within 1,000 to 5,000. The additive with the optimal composition contains a solvent, a thickener, an anticorrosion substance, anticoagulants, surfacants (PAV) and so on. A highly concentrated suspension of oil coke and water with a 50 to 75 percent concentration of powder form petroleum coke may be produced using the patented additive. Such a suspension is characterized by low viscosity, high stability and forms no foam during processing.

  14. Factors affecting coke size and fissuring during cokemaking part 2

    Energy Technology Data Exchange (ETDEWEB)

    Merrick Mahoney; Jeff Keating; Susan Woodhouse [BHP Billiton Newcastle Technology Centre (Australia)

    2007-12-15

    This work addressed the mechanism of fissuring during metallurgical cokemaking and extends on a previous ACARP project. Considerable progress has been made in understanding the mechanism by an integrated modelling work; experimental program. The work points to opportunities for controlling the carbonisation process to achieve required outcomes in terms of coke lump size and distribution. Key outcomes of the work included: A methodology for determination of the minimum spacing between fissures, and the time at which period doublings (i.e. every second fissure stopping) occur, has been developed and implemented. Implementation of the methodology allows the determination of the complete fissure pattern (at least those perpendicular to the oven walls) for a given coke oven/charge configuration. A plausible mechanistic explanation of the formation of lateral fissures (those that are parallel to the oven walls) has been developed. Knowledge of the fissure pattern, combined with the lateral fissuring explanation, enables the determination of typical size and shape of lumps after stabilisation of the coke.

  15. Human health risk characterization of petroleum coke calcining facility emissions.

    Science.gov (United States)

    Singh, Davinderjit; Johnson, Giffe T; Harbison, Raymond D

    2015-12-01

    Calcining processes including handling and storage of raw petroleum coke may result in Particulate Matter (PM) and gaseous emissions. Concerns have been raised over the potential association between particulate and aerosol pollution and adverse respiratory health effects including decrements in lung function. This risk characterization evaluated the exposure concentrations of ambient air pollutants including PM10 and gaseous pollutants from a petroleum coke calciner facility. The ambient air pollutant levels were collected through monitors installed at multiple locations in the vicinity of the facility. The measured and modeled particulate levels in ambient air from the calciner facility were compared to standards protective of public health. The results indicated that exposure levels were, on occasions at sites farther from the facility, higher than the public health limit of 150 μg/m(3) 24-h average for PM10. However, the carbon fraction demonstrated that the contribution from the calciner facility was de minimis. Exposure levels of the modeled SO2, CO, NOx and PM10 concentrations were also below public health air quality standards. These results demonstrate that emissions from calcining processes involving petroleum coke, at facilities that are well controlled, are below regulatory standards and are not expected to produce a public health risk.

  16. Holographic quenches and anomalous transport

    Science.gov (United States)

    Ammon, Martin; Grieninger, Sebastian; Jimenez-Alba, Amadeo; Macedo, Rodrigo P.; Melgar, Luis

    2016-09-01

    We study the response of the chiral magnetic effect due to continuous quenches induced by time dependent electric fields within holography. Concretely, we consider a holographic model with dual chiral anomaly and compute the electric current parallel to a constant, homogeneous magnetic field and a time dependent electric field in the probe approximation. We explicitly solve the PDEs by means of pseudospectral methods in spatial and time directions and study the transition to an universal "fast" quench response. Moreover, we compute the amplitudes, i.e., residues of the quasi normal modes, by solving the (ODE) Laplace transformed equations. We investigate the possibility of considering the asymptotic growth rate of the amplitudes as a well defined notion of initial time scale for linearized systems. Finally, we highlight the existence of Landau level resonances in the electrical conductivity parallel to a magnetic field at finite frequency and show explicitly that these only appear in presence of the anomaly. We show that the existence of these resonances induces, among others, a long-lived AC electric current once the electric field is switched off.

  17. Effect of pretreatment methods of raw material on coking of needle coke from coal tar pitch by delayed coking%原料预处理方法对延迟焦化成焦的影响

    Institute of Scientific and Technical Information of China (English)

    吴甦; 王磊; 王小冰; 菜闯

    2012-01-01

    介绍了针状焦的工业生产方法,分析了不同的原料软沥青处理方法以及原料的结构和组成对延迟焦化成焦的影响.%The methods of manufacturing needle coke were introduced. And the effects of different pretreatment methods, the structure and composition of the raw material on the formation of needle coke from coal tar pitch by delayed coking were analyzed.

  18. 46 CFR 148.04-17 - Petroleum coke, calcined, at 130 °F or above.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Petroleum coke, calcined, at 130 °F or above. 148.04-17...-17 Petroleum coke, calcined, at 130 °F or above. (a) The requirements of this part do not apply to bulk shipments of petroleum coke, calcined, on any vessel when the material is less than 130 °F. (b...

  19. Analysis of changes in the chemical composition of the blast furnace coke at high temperatures

    Directory of Open Access Journals (Sweden)

    A. Konstanciak

    2012-12-01

    Full Text Available Purpose: The main purpose of this paper was to analyze the behavior of coke in the blast furnace. The analysis of changes in chemical composition of coke due to impact of inert gas and air at different temperatures was made. The impact of the application of the thermoabrasion coefficient on the porosity of coke was also analyzed.Design/methodology/approach: By applying the Computer Thermochemical Database of the TERMO system (REAKTOR1 and REAKTOR3 three groups of substances can be distinguished. The chemical composition of blast furnace coke and the results of calculations of changes of chemical composition of coke heat treated under certain conditions were compared. The structural studies of these materials were presented.Findings: The results of the analysis of ash produced from one of Polish cokes was taken for consideration. This is not the average composition of Polish coke ashes, nevertheless it is representative of most commonly occurring chemical compositions.Practical implications: Thanks to the thermochemical calculations it is possible to predict ash composition after the treatment in a blast furnace. Those information was crucial and had an actual impact on determining the coke quality.Originality/value: Presentation of the analytical methods which, according to author, can be very useful to evaluate and identify the heat treatment for blast furnaces cokes. The research pursued represents part of a larger project carried out within the framework of Department Extraction and Recycling of Metals, Czestochowa University of Technology.

  20. Graphitization of Coke and Its Interaction with Slag in the Hearth of a Blast Furnace

    Science.gov (United States)

    Li, Kejiang; Zhang, Jianliang; Liu, Yanxiang; Barati, Mansoor; Liu, Zhengjian; Zhong, Jianbo; Su, Buxin; Wei, Mengfang; Wang, Guangwei; Yang, Tianjun

    2016-04-01

    Coke reaction behavior in the blast furnace hearth has yet to be fully understood due to limited access to the high temperature zone. The graphitization of coke and its interaction with slag in the hearth of blast furnace were investigated with samples obtained from the center of the deadman of a blast furnace during its overhaul period. All hearth coke samples from fines to lumps were confirmed to be highly graphitized, and the graphitization of coke in the high temperature zone was convinced to start from the coke surface and lead to the formation of coke fines. It will be essential to perform further comprehensive investigations on graphite formation and its evolution in a coke as well as its multi-effect on blast furnace performance. The porous hearth cokes were found to be filled up with final slag. Further research is required about the capability of coke to fill final slag and the attack of final slag on the hearth bottom refractories since this might be a new degradation mechanism of refractories located in the hearth bottom.

  1. High PCI and low coke rate BF operation in ArcelorMittal Flat Carbon Europe

    Energy Technology Data Exchange (ETDEWEB)

    Dauwels, G.; Clairay, S.; Hess, E.; Janz, J.; Goimard, J.C.; Eymond, J.L. [ArcelorMittal (France)

    2008-07-01

    Coke production capacity within ArcelorMittal is not sufficient to provide the amount of coke needed for the total hot metal production. In order to address the challenges regarding coke availability, ArcelorMittal Flat Carbon Europe (FCE) sector has applied a low coke operation pulverized coal injection (PCI) technology to 17 of its blast furnaces across Europe. This paper described the charging pattern, blast conditions, hearth drainage and burden quality needed for high PCI rates. The coal injection rates of the different blast furnaces has been increased from 150-180 kg/thm to 180-200 kg/thm with a good replacement ratio. The lessons learned from high coal injection rate operations were discussed. The long term objective for FCE is to average a coal injection level of 200-220 kg/thm. This paper also discussed issues of coal quality, such as selection of coal; influence of coal quality on the blast furnace operation; and influence of coke quality on hearth drainage and hot metal quality. Coke quality was also discussed in terms of coke requirements and new global coke quality parameters. The difficulties in increasing PCI rate were shown to be associated with ferrous burden quality, particularly sinter. Adjustments to coke layer thickness can prevent instabilities. 8 refs., 23 figs.

  2. The effects of ash and maceral composition of Azdavay and Kurucasile (Turkey) coals on coking properties

    Energy Technology Data Exchange (ETDEWEB)

    Toroglu, I. [Zonguldak Karaelmas University, Zonguldak (Turkey). Faculty of Engineering

    2006-07-01

    In this study, investigations were made as to the effect of the maceral compositions and mineral matter content of Azdavay and Kurucasile coals on the coking property. Chemical and maceral analyses and coking properties were determined for the products of the float-sink procedure. The coking properties were established on the basis of free swelling index and Ruhr dilatometer tests. Maceral analyses showed that as the ash content of a coal containing both high and medium volatile matter increases, its effective maceral proportion decreases, and the coking property is affected in an unfavorable way.

  3. Feedback control strategy of longitudinal temperature and finished carbonization time for coke oven and its application

    Institute of Scientific and Technical Information of China (English)

    Fang Huo; Zhi Wen; Dong Chen; Yueling Shen; Yongqin Zhang; Xiaoming Zhi

    2004-01-01

    Based on the detailed analysis of the third coke oven in BaoSteel, a feedback control strategy of longitudinal temperature and finished carbonization time of coke ovens was proposed and it was applied to the third coke oven in BaoSteel. As a result, the ratio of the instance that the absolute deviation of the longitudinal temperature is within ±7°C and the finished carbonization time within ± 10 rain is more than 80%, having acquired the patent saving effect of an energy consumption lowered by 2.92%. At the same time, it can provide an example for the same coke ovens inside and outside the nation.

  4. Improvement in operating conditions of coke oven batteries with long service life

    Energy Technology Data Exchange (ETDEWEB)

    Obertenev, V.N.; Bondarchuk, P.N.; Krut' ko, I.G.; Sheptovitskii, M.S.; Kaftan, Yu.S.; Shul' ga, I.V.; Vol' fovskii, A.G. (Mariupol' skii Koksokhimicheskii Zavod (USSR))

    1991-01-01

    Discusses operation of the coke oven battery No 1 in the Mariupol' coking plant constructed in 1949. Twenty-five of 69 coke oven chambers had liners deformed due to wear. In 1988-1989 a number of failures occurred due to accumulation of pyrolysis products and tar on coke oven walls. Excessive liner wear negatively influenced coking conditions (e.g. reducing the bulk density of charged coal, increasing the buildup on coke oven walls, increasing the density and viscosity of coal tar and content of solid particles in the tar). Increased viscosity and content of solid particles in the tar increased failure rates of a tar transport system. Coal tar properties in the Mariupol' plant and 8 other plants in the USSR are comparatively evaluated. Specific properties of coal tar from the Mariupol' plant and their causes were determined. On the basis of the evaluations coal tar properties were controlled by changing coal mixture composition (content of gas coal was reduced to 32% of G and GZh types). Reducing content of gas coal in the mixtures reduced coke oven failure rate, increased coke compression strength by 0.6% and reduced coke abrasion by 0.25%. 5 refs.

  5. System for reducing emissions during coke oven charging; System zur Emissionsverringerung beim Fuellen von Koksoefen

    Energy Technology Data Exchange (ETDEWEB)

    Schuecker, Franz-Josef [ThyssenKrupp Industrial Solutions AG, Dortmund (Germany). Head of Oven Machine Dept., Coke Plant Technologies

    2014-10-01

    This article describes a process which reduces emissions from coke production in coke plants. The focus is on the charging process, which can be partly responsible for the fact that statutory emissions limits, which were originally met, are exceeded as coke plants get older. This article presents a solution in the form of a newly developed system that allows the oven charging system - the charging car - to respond to age-related changes in the geometry of a coke oven and thereby reduce the level of emissions.

  6. Neural Variability Quenching Predicts Individual Perceptual Abilities.

    Science.gov (United States)

    Arazi, Ayelet; Censor, Nitzan; Dinstein, Ilan

    2017-01-04

    Neural activity during repeated presentations of a sensory stimulus exhibits considerable trial-by-trial variability. Previous studies have reported that trial-by-trial neural variability is reduced (quenched) by the presentation of a stimulus. However, the functional significance and behavioral relevance of variability quenching and the potential physiological mechanisms that may drive it have been studied only rarely. Here, we recorded neural activity with EEG as subjects performed a two-interval forced-choice contrast discrimination task. Trial-by-trial neural variability was quenched by ∼40% after the presentation of the stimulus relative to the variability apparent before stimulus presentation, yet there were large differences in the magnitude of variability quenching across subjects. Individual magnitudes of quenching predicted individual discrimination capabilities such that subjects who exhibited larger quenching had smaller contrast discrimination thresholds and steeper psychometric function slopes. Furthermore, the magnitude of variability quenching was strongly correlated with a reduction in broadband EEG power after stimulus presentation. Our results suggest that neural variability quenching is achieved by reducing the amplitude of broadband neural oscillations after sensory input, which yields relatively more reproducible cortical activity across trials and enables superior perceptual abilities in individuals who quench more.

  7. Development of the super coke oven for productivity and environment enhancement toward the 21st century (SCOPE 21); Sekitan kodo tenkan cokes seizo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Sugiyama, T. [Center for Coal Utilization, Japan, Tokyo (Japan); Nakashima, Y.; Nishioka, K.; Otsuka, J. [The Japan Iron and Steel Federation, Tokyo (Japan)

    1996-09-01

    Serious shortage is predicted on cokes for blast furnaces in the first half of the 21st century. In order to deal flexibly with the fluid world market in the future, it is necessary to have a technology developed, by which coals from coking coal to non-coking dust coal can be used. The Japan Iron and Steel Federation and the Center for Coal Utilization, Japan are working on research and development of a new process with enhanced environmentality and economy (SCOPE 21) as a coke manufacturing process to respond to the requirements arisen from the above situation. The process is assessed basing on basic technological seeds such as rapid coal heating and high-speed carbonization and reformation of middle to low temperature cokes. The organizations are moving forward an eight-year development program which has started in fiscal 1994. This paper reports the summary of the development, and results of investigations and researches performed during fiscals 1994 and 1995. Rapid heating tests, middle to low temperature coke reformation tests, and tests for plug transportation of high-temperature coal have been performed. It has been verified, for example, that rapid coal heating can improve coke strength. The development work is being promoted toward grain size distribution and upscaling problems. 5 refs., 16 figs., 2 tabs.

  8. Optimisation of coal blend and bulk density for coke ovens by vibrocompacting technique non-recovery ovens

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, P.P.; Vinoo, D.S.; Yadav, U.S.; Ghosh, S.; Lal, J.P.N. [J.S.W. Steel Ltd, Bellary (India)

    2007-09-15

    The quality of coke produced in a coke oven depends on the coal blend characteristics and carbonisation conditions. Scarcity of good quality coking coal made it necessary to look for techniques capable of producing superior coke from inferior coals. Precarbonisation techniques improve the bulk density of the coal charge and produce good quality coke from inferior coals. The stamp charging technique, the most effective among them requires finer crushing of coal and higher moisture as binder, both requiring additional energy. JSW Steel has adopted vibrocompaction along with non-recovery ovens for its 1.2 Mtpa coke production. This is a highly ecofriendly coke making process producing excellent quality coke from inferior coals. It increases the bulk density of cake, similar to stamp charging, using compaction in place of stamping. A cake density of 1.10 t m{sup -3} has been achieved using the vibrocompacting technique with optimum moisture and crushing fineness. Coal blend containing up to 35% soft coal and coking coal, having 32% volatile matter have been successfully used to produce a coke with coke strength after reaction >65%, coke reactivity index <25% and M10 <6%. The paper discusses the experience of operating vibrocompaction non-recovery coke ovens.

  9. Coke Formation During Hydrocarbons Pyrolysis. Part One: Steam Cracking Formation de coke pendant la pyrolise des hydrocarbures. Première partie : vapocraquage

    Directory of Open Access Journals (Sweden)

    Weill J.

    2006-11-01

    Full Text Available Thermal cracking is always accompanied by coke formation, which becomes deposited on the wall and limits heat transfers in the reactor while increasing pressure drops and possibly even plugging up the reactor. This review article covers undesirable coking operations in steam craking reactors. These coking reactions may take place in the gas phase and/or on the surface of the reactor, with coke being produced during pyrolysis by a complex mechanism that breaks down into a catalytic sequence and a noncatalytic sequence. After a brief description of different experimental set-ups used to measure the coke deposition, on the basis of research described in the literature, the different factors and their importance for coke formation are listed. In particular, we describe the effects of surface properties of stainless-steel and quartz reactors as well as the influence of the cracked feedstock, of temperature, of dilution, of residence time and of the conversion on coke deposition. Some findings about the morphology of coke are described and linked to formation mechanisms. To illustrate this review, some particularly interesting research is referred to concerning models developed to assess coke formation during propane steam cracking. Le craquage thermique est toujours accompagné de la formation de coke qui, en se déposant à la paroi, limite les transferts de chaleur au réacteur, augmente les pertes de charges et même peut boucher celui-ci. Cet article fait le point sur les réactions indésirables de cokage dans les réacteurs de vapocraquage. Ces réactions de cokage peuvent avoir lieu en phase gazeuse et/ou sur la surface du réacteur, le coke étant produit pendant la pyrolyse par un mécanisme complexe qui se décompose en une séquence catalytique et une séquence non catalytique. Après une brève présentation des différents montages expérimentaux utilisés pour mesurer le dépôt de coke, il est mentionné, à partir de travaux de la

  10. Quenched QCD near the chiral limit

    CERN Document Server

    Göckeler, M; Petters, D; Pleiter, D; Rakow, P E L; Schierholz, G

    2000-01-01

    A numerical study of quenched QCD for light quarks is presented using O(a)improved fermions. Particular attention is paid to the possible existence anddetermination of quenched chiral logarithms. A `safe' region to use for chiralextrapolations appears to be at and above the strange quark mass.

  11. Monte Carlo Tools for Jet Quenching

    OpenAIRE

    Zapp, Korinna

    2011-01-01

    A thorough understanding of jet quenching on the basis of multi-particle final states and jet observables requires new theoretical tools. This talk summarises the status and propects of the theoretical description of jet quenching in terms of Monte Carlo generators.

  12. Quenched chiral perturbation theory to one loop

    NARCIS (Netherlands)

    Colangelo, Gilberto; Pallante, Elisabetta

    1998-01-01

    We calculate the divergences of the generating functional of quenched chiral perturbation theory at one loop, and renormalize the theory by an appropriate definition of the counterterms. We show that the quenched chiral logarithms can be accounted for by defining a renormalized B0 parameter which, a

  13. Quenched Chiral Perturbation Theory to one loop

    NARCIS (Netherlands)

    Colangelo, G.; Pallante, E.

    1998-01-01

    The divergences of the generating functional of quenched Chiral Perturbation theory (qCHPT) to one loop are computed in closed form. We show how the quenched chiral logarithms can be reabsorbed in the renormalization of the B0 parameter of the leading order Lagrangian. Finally, we do the chiral powe

  14. Thermal quenching and electron traps in LSO

    Energy Technology Data Exchange (ETDEWEB)

    Kappers, L.A. E-mail: kappers@uconnvm.uconn.edu; Bartram, R.H.; Hamilton, D.S.; Lempicki, A.; Glodo, J

    2003-05-01

    It is demonstrated by comparison of thermoluminescence and scintillation light outputs of LSO as functions of radiation time that a previously suggested thermal quenching correction is inappropriate. Approximate solutions of rate equations are employed to infer absolute trap concentrations and to explore the effects of thermal quenching on the shapes of thermoluminescence glow curves.

  15. MSFC Electrostatic Levitator (ESL) Rapid Quench System

    Science.gov (United States)

    SanSoucie, Michael P.; Craven, Paul D.; Rogers, Jan R.

    2014-01-01

    The NASA Marshall Space Flight Center (MSFC) Electrostatic Levitator (ESL) Laboratory is a unique facility for investigators studying high-temperature materials. The laboratory boasts two levitators in which samples can be levitated, heated, melted, undercooled, and resolidified, all without the interference of a container or data-gathering instrument. The ESL main chamber has been upgraded with the addition of a rapid quench system. This system allows samples to be dropped into a quench vessel that can be filled with a low melting point material, such as a gallium or indium alloy. Thereby allowing rapid quenching of undercooled liquid metals. Up to 8 quench vessels can be loaded into the quench wheel, which is indexed with LabVIEW control software. This allows up to 8 samples to be rapidly quenched before having to open the chamber. The system has been tested successfully on several zirconium samples. Future work will be done with other materials using different quench mediums. Microstructural analysis will also be done on successfully quench samples.

  16. Preparation and Anti-coking Property of SiO2/S Coating on HP40 Tube

    Institute of Scientific and Technical Information of China (English)

    周建新; 徐宏; 张莉; 刘京雷; 戚学贵; 彭博

    2007-01-01

    SiO2/S coating was prepared on the inner surface of an HP40 tube using dimethyldisulfide and tetraethylorthosilicate by atmospheric pressure chemical vapor deposition (APCVD) to alleviate catalytic coking on the inner surface of radiant tube for ethylene production in petrochemical plants. The comparative coking experiments with the coated and uncoated HP40 tubes were carried out under the same cracking conditions. SiO2/S coating was compact and had excellent anti-coking property. The coke on the coated HP40 tube was about 22% of that on the uncoated HP40 tube, and only small granular coke was deposited on the coated HP40 tube. However, the filamentous coke formed on the uncoated HP40 tube. The thermal stability of SiO2/S coating was satisfactory at cracking temperature, and the anti-coking property of SiO2/S coating was still over 60% after 3 coking and decoking cycles.

  17. Transient Loschmidt echo in quenched Ising chains

    Science.gov (United States)

    Lupo, Carla; Schiró, Marco

    2016-07-01

    We study the response to sudden local perturbations of highly excited quantum Ising spin chains. The key quantity encoding this response is the overlap between time-dependent wave functions, which we write as a transient Loschmidt Echo. Its asymptotics at long time differences contain crucial information about the structure of the highly excited nonequilibrium environment induced by the quench. We compute the echo perturbatively for a weak local quench but for arbitrarily large global quench, using a cumulant expansion. Our perturbative results suggest that the echo decays exponentially, rather than power law as in the low-energy orthogonality catastrophe, a further example of quench-induced decoherence already found in the case of quenched Luttinger liquids. The emerging decoherence scale is set by the strength of the local potential and the bulk excitation energy.

  18. Finite Element Simulation of Metal Quenching

    Institute of Scientific and Technical Information of China (English)

    方刚; 曾攀

    2004-01-01

    The evolution of the phase transformation and the resulting internal stresses and strains in metallic parts during quenching were modeled numerically. The numerical simulation of the metal quenching process was based on the metallo-thermo-mechanical theory using the finite element method to couple the temperature, phase transformation, and stress-strain fields. The numerical models are presented for the heat treatment and kinetics of the phase transformation. The finite element models and the phase transition kinetics accurately predict the distribution of the microstructure volume fractions, the temperature, the distortion, and the stress-strain relation during quenching. The two examples used to validate the models are the quenching of a small gear and of a large turbine rotor. The simulation results for the martensite phase volume fraction, the stresses, and the distortion in the gear agree well with the experimental data. The models can be used to optimize the quenching conditions to ensure product quality.

  19. Quench Heater Studies for the LHC Magnets

    CERN Document Server

    Rodríguez-Mateos, F

    2001-01-01

    About 2000 LHC (CERN's Large Hadron Collider) superconducting magnets will be protected with quench heaters against development of excessive voltage and overheating after a resistive transition. The quench heater strips are powered by capacitor bank discharge power supplies. The strips are made of stainless steel partially plated with copper to reduce their resistance and to allow for the connection of quench heaters in series. The strips are embedded in between two polyimide foils. The initial power density and the current decay time determine the quench heater effectiveness. Since only one type of heater power supply will be available, the copper plating cycle is adapted for the various magnet types to keep the resistance of the heater circuit constant. Different quench heater designs have been tested on various prototype magnets to optimise the copper-plating cycle and the electric insulation of the heater strip. This paper summarises the experimental results and computations that allowed to finalise the h...

  20. QUENCH STUDIES AND PREHEATING ANALYSIS OF SEAMLESS

    Energy Technology Data Exchange (ETDEWEB)

    Palczewski, Ari [JLAB; Geng, Rongli [JLAB; Eremeev, Grigory [JLAB

    2013-09-01

    One of the alternative manufacturing technologies for SRF cavities is hydroforming from seamless tubes. Although this technology has produced cavities with gradient and Q-values comparable to standard EBW/EP cavities, a few questions remain. One of these questions is whether the quench mechanism in hydroformed cavities is the same as in standard electron beam welded cavities. Towards this effort Jefferson Lab performed quench studies on 2 9 cell seamless hydroformed cavities. These cavities include DESY's - Z163 and Z164 nine-cell cavities hydroformed at DESY. Initial Rf test results Z163 were published in SRF2011. In this report we will present post JLAB surface re-treatment quench studies for each cavity. The data will include OST and T-mapping quench localization as well as quench location preheating analysis comparing them to the observations in standard electron beam welded cavities.

  1. 焦炉推焦粉尘治理工艺选择及设备配置%Technological Selection of Dust Treatment and Equipment Collocation While Coking in Coke Oven

    Institute of Scientific and Technical Information of China (English)

    姜乃斌; 邢显昌

    2012-01-01

      The article probes into the technological selection of dust treatment and equipment col ocation while coke choosing in coke oven; makes focus on and analyzes the three main topics of flue dust col ection, transportation and dust filter-ing of dust treatment in coke oven tapping.

  2. 活性焦烟气脱硫技术及其应用前景%Desulfurization Technology for Flue Gas by Active Coke and Its Application Prospect

    Institute of Scientific and Technical Information of China (English)

    汪家铭

    2012-01-01

    Desulfurization technology for flue gas by active coke was using its inherent functions of adsorption, catalysis and filtration,it was a dry purification treatment for the sulfur contained flue gas, in same one of reactor the three functions of desulfurization, de-nitride and de-dust were finished. Author hasintroduced the basic principle,process flow,technical feature,studying and developing situation taking coal as mainraw material to produce the active coke ; has compared the desulfurization hy active coke with the other some kinds of conventional desulfurization processes. Result indicates that the desulfurization technology of flue gas by active coke has an obvious superiority in the aspects of desulfurization rate,utilization of by-product,investment of plant and operating cost etc.%活性焦烟气脱硫技术利用活性焦特有的吸附、催化和过滤功能,对含硫烟气进行干法净化处理,在同1个反应器内完成脱硫、脱硝、除尘3种功能。介绍了以煤为主要原料生产活性焦的基本原理、工艺流程、技术特点和研发概况;将活性焦脱硫工艺与其他几种常用的脱硫工艺进行了对比,结果表明,活性焦烟气脱硫技术在脱硫率、副产品利用、装置投资及运行费用等方面均具有明显优势。

  3. Use of Coke Oven Gas during shutdown period of Direct Reduced Iron Plant for Steam Generation: Experimentation and Optimization

    Directory of Open Access Journals (Sweden)

    Harish C. Dalai

    2015-11-01

    Full Text Available Development of any country is largely based on its magnitude of industrial growth. Steel industries in India took a leading role in the world after mid-sixties. During the last five decades, the steel industries all over the world made considerable developments in new methods for reducing iron ore directly to metallic iron for use as commercial scrap substitute in the manufacture of steels. BSL has been producing steel and other products over last two decades and the above process is used in BSL for one decade. Direct reduction is a process, which extracts high metallic solid iron by removing oxygen from iron ore or any other iron oxides without passing through molten stage, i.e. solid state reduction. The product, so formed is known as directly reduced tron (DRI or Sponge Iron. Due to shortage of raw material or any other problem in DRI sections, the DRI section undergoes a temporary short down. During the shutdown period the equipments tend to be idle. To keep the equipment ready for operation as well as to maintain the plants economy an alternate methodology is used in this research. Various operations are: CO gas from Coke Oven, DRI, Steam Generation, and Power Generation.

  4. Application of fine-grained coke breeze fractions in the process of iron ore sintering

    Directory of Open Access Journals (Sweden)

    M. Niesler

    2014-01-01

    Full Text Available The testing cycle, described in the paper, included fine-grained coke breeze granulation tests and iron concentrate sintering tests with the use of selected granulate samples. The use of granulated coke breeze in the sintering process results in a higher process efficiency, shorter sintering duration and fuel saving.

  5. Interaction of bonding agent with filler in coking-pitch compositions

    Energy Technology Data Exchange (ETDEWEB)

    Firsanov, A.V.; Beylina, N.Yu.; Kolodin, E.A.; Ostrovskiy, V.S.; Proskuryakov, V.A.; Shipkov, N.N.

    1983-01-01

    Coke's selective sorption of highly molecular components of pitch was determined with the aid of gel-penetrating chromatography. It was shown that behavior of pitch in coking-pitch compositions, as well as the nature of release of pyrolysis products is determined by dispersion of the filler.

  6. Characteristics of interaction between petrographically differing coals in mixtures for coking

    Energy Technology Data Exchange (ETDEWEB)

    Stankevich, A.S.; Proskuryakov, A.E.; Zolotukhin, Yu.A.

    1983-09-01

    Coal mixtures used for coking in the East of the USSR are characterized by intensive fluctuations of coak rank and petrology. Reflectivity coefficient of vitrinite ranges from 0.73 to 1.70% and content of caking components ranges from 30 to 88%. Evaluations show that fluctuations of reflectivity coefficient of vitrinite and fluctuations of caking component content in coal negatively influence coke mechanical properties and increase coke reactivity. Effects of coal macerals and microlithotypes in black coal from the Kuzbass on coke properties are analyzed. The following microlithotypes are separated from coal: vitrite, clarite, duroclarite, clarodurite, durite, fusite, semivitrinite, mineralized coal and rocks. Effects of macerals and microlithotypes in 50 coal mixtures on coke quality and coke properties are analyzed. Regression analysis is used. On the basis of this analysis equations for forecasting coke properties are derived. Petrologic nonhomogeneity of coal mixtures deteriorates conditions for chemical interaction between components with differing genetics and negatively influences caking of vitrite and fusite (or durite). Coke from coal characterized by petrologic nonhomogeneity has a structure with low degree of order, low mechanical and structural strength and increased reactivity. (5 refs.) (In Russian)

  7. Development and Application of Zero Expansion Silica Brick for Hot Repairing of Coke Oven

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiuqin; ZHI Xiaoming; WANG Hongmei

    2003-01-01

    In order to meet the needs of hot repairing technology of coke oven, the zero expansion silica brick with super properties has been developed, and the problem of poor thermal stability of common silica brick has been overcomned. This product can be directly used after being rapidly heated after construction. At present, it has been applied in coke ovens in Italy and Baosteel.

  8. Nature of nitrogen specie in coke and their role in NOx formation during FCC catalyst regeneration.

    NARCIS (Netherlands)

    Babych, Igor V.; Seshan, Kulathuiyer; Lefferts, Leonardus

    2005-01-01

    NOx emission during the regeneration of coked fluid catalytic cracking (FCC) catalysts is an environmental problem. In order to follow the route to NOx formation and try to find ways to suppress it, a coked industrial FCC catalyst has been prepared using model N-containing compounds, e.g., pyridine,

  9. Environment protection in the area of by-products facilities in coking plant

    Energy Technology Data Exchange (ETDEWEB)

    Stefan Tomal; Henryk Zembala; Krzysztof Kalinowski; Milan Fedorov; Ludovt Kosnac; Jan Hromiak [Biuro Projektow Koksoprojekt Sp. z o.o., Zabrze (Poland)

    2004-07-01

    20 slides/overheads outline the presentation on the subject of the environmental protection program implemented at the U.S. Steel Kosice Coking Plant. Actions taken include the control of emissions by a system of cooling coke oven gas. A hermetically sealed system uses nitrogen flow for tar management and hermetic loading of the liquid coal by-product Benzol.

  10. 76 FR 74810 - Foundry Coke From China; Institution of a Five-Year Review

    Science.gov (United States)

    2011-12-01

    ... COMMISSION Foundry Coke From China; Institution of a Five-Year Review AGENCY: United States International... duty order on imports of foundry coke from China (66 FR 48025). Following five-year reviews by Commerce... merchandise that is within the scope of the five-year review, as defined by the Department of Commerce. (2...

  11. Carbon molecular sieves from bituminous coal by controlled coke deposition

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, S.N.; Patwardhan, S.R.; Gangadhar, B. (Indian Institute of Technology, Bombay (India). Dept. of Chemical Engineering)

    1992-01-01

    Carbon molecular sieves (CMS) and zeolites are widely used as microporous sieving solids for gas and liquid separations. However, due to hydrophobicity, better thermal stability, and neutrality in both acidic and alkaline media, CMSs have definite advantages over zeolites. In the present work, an effort has been made to develop suitable process conditions for synthesizing CMSs from the locally available bituminous coal. The coal was crushed, milled, and agglomerated with sulfate pulp waste liquor (SPWL) or coal-tar pitch (CTP) as the binders, and then carbonized in nitrogen atmosphere at 800{degree}C for about 60 minutes. In order to narrow down the pore mouth sizes, acetylene and benzene were each cracked separately at 800{degree}C to facilitate the deposition of coke on the char. Acetylene and benzene were cracked for 3 to 10 minutes, and 10 to 30 minutes, respectively. Acetylene cracked samples did not show good separation, probably because of over-coking in deeper locations. In contrast benzene cracked samples were found to be highly suitable for CO{sub 2}-CH{sub 4} separation. The best result (i.e. uptake ratio of 39.9) was obtained for feed benzene entrainment in N{sub 2} of 1.27 x 10{sup -4} g/ml, cracking time of 30 minutes, and this ratio was more than 10 times that of non-coked sample. CMS samples produced using SPWL as binder showed poor O{sub 2}/N{sub 2} uptake ratios throughout (1 to 1.5), whereas samples with CTP as binder showed far more encouraging results, the best uptake ratio being 5.5 for benzene-nitrogen feed stream containing 3.508 x 10{sup -4} g/ml benzene and 5 minutes cracking time. This ratio is about 5.5 times more than that of uncoked sample. 4 tabs., 10 figs., 17 refs.

  12. High Heat Flux Surface Coke Deposition and Removal Assessment

    Science.gov (United States)

    2015-01-01

    etc. have on coke deposition from RP-1 and RP-2 as well as showing that we can oxidize and remove these deposits using ozone , would be very...Meeting; 29 Apr. - 3 May, Colorado Springs, CO. 10Billingsley, M.C. H.Y. Lyu and R.W. Bates (2007). "Experimental and Numerical Investigations of RP...5th Modeling and Simulation Subcommittee Joint Meeting, Denver, CO, 14-17 May. 11Linne, D.L., M. L. Meyer, T. Edwards, and D. A. Eitman (1997

  13. Study on soot purifying of molding shop in coking factory

    Institute of Scientific and Technical Information of China (English)

    LI Duo-song; ZHANG Hui; BAI Xiang-yu

    2006-01-01

    Exhaust gas in molding shop was complicated in component and characteristic in Iow thickness asphalt smoke, mass steam-gas and dust. It was difficult to purify the soot with common purifier. So we must consider them roundly and develop new multifunction purifier. PFP multifunction soot purifier was made on the base of design optimization and was installed at Shenhuo Coking Factory in 2004. The combined effects of multi- mechanism in purifier make purifying ratio keep in high level. The remove ratio of smut reaches at 92.8%, and asphalt smoke at 83.7%.

  14. Dry Etching

    DEFF Research Database (Denmark)

    Stamate, Eugen; Yeom, Geun Young

    2016-01-01

    Production of large-area flat panel displays (FPDs) involves several pattern transfer and device fabrication steps that can be performed with dry etching technologies. Even though the dry etching using capacitively coupled plasma is generally used to maintain high etch uniformity, due to the need...... for the higher processing rates in FPDs, high-density plasma processing tools that can handle larger-area substrate uniformly are more intensively studied especially for the dry etching of polysilicon thin films. In the case of FPD processing, the current substrate size ranges from 730 × 920 mm (fourth...... generation) to 2,200 × 2,500 mm (eighth generation), and the substrate size is expected to increase further within a few years. This chapter aims to present relevant details on dry etching including the phenomenology, materials to be etched with the different recipes, plasma sources fulfilling the dry...

  15. Discussions on denitration technology for exhaust gas of coke oven battery%焦炉烟气脱硝工艺技术探讨

    Institute of Scientific and Technical Information of China (English)

    李良华; 刘杰; 曹银平

    2015-01-01

    介绍了控制焦炉烟气氮氧化物生成的低氮燃烧技术和焦炉烟气脱硝技术,阐述了干法和湿法烟气脱硝技术的适用性和需解决的问题。%This paper introduces the low-nitrogen combustion technology to control NOx generation in exhaust gas of coke oven battery and the denitration technology for exhaust gas,and it also elaborates the applicability of dry denitration and wet denitration method and the problems to be solved.

  16. Application of SketchUp in Coke Oven Three-Dimensional Digital Modeling

    Directory of Open Access Journals (Sweden)

    Shuguang Ouyang

    2013-01-01

    Full Text Available Coke oven, which is a large industrial furnace, is complex in structure. A two-dimensional structure diagram can hardly help one observe the inner structure of a coke oven or master its working principle comprehensively. In order to solve this problem, a complete 3D digital model of a coke oven is generated by assembling the three-dimensional models of coke oven components created with SketchUp. It enables users to section the various components of the cove oven. The outer appearance and inner structure of the oven components also can be displayed visually from several different orientations. Moreover, it is convenient to storage and carry, operation easily and fast. It can be displayed on an ordinary computer and occupies no space at the laboratory. Meanwhile, a large sum of money that used for purchasing a physical coke oven model can be saved.

  17. Microwave-assisted grinding of metallurgical coke; Molienda asistida con microondas de un coque metalurgico

    Energy Technology Data Exchange (ETDEWEB)

    Ruisanchez, E.; Juarez-Perez, E. J.; Arenillas, A.; Bermudez, J. M.; Menendez, J. A.

    2014-10-01

    Metallurgical cokes are composed of graphitic carbon (s2p2) and different inorganic compounds with very different capacities to absorb microwave radiation. Moreover, due to the electric conductivity shown by the metallurgical cokes, microwave radiation produces electric arcs or microplasmas, which gives rise to hot spots. Therefore, when these cokes are irradiated with microwaves some parts of the particle experiment a rapid heating, while some others do not heat at all. As a result of the different expansion and stress caused by thermal the shock, small cracks and micro-fissures are produced in the particle. The weakening of the coke particles, and therefore an improvement of its grind ability, is produced. This paper studies the microwave-assisted grinding of metallurgical coke and evaluates the grinding improvement and energy saving. (Author)

  18. CO2 mitigation by carbon nanotube formation during dry reforming of methane analyzed by factorial design combined with response surface methodology

    Institute of Scientific and Technical Information of China (English)

    Tiago P. Braga; Regina C. R. Santos; Barbara M. C. Sales; Bruno R. da Silva; Antônio N. Pinheiro; Edson R. Leite; Antoninho Valentini

    2014-01-01

    A factorial experimental design was combined with response surface methodology (RSM) to opti-mize the catalyzed CO2 consumption by coke deposition and syngas production during the dry re-forming of CH4. The CH4/CO2 feed ratio and the reaction temperature were chosen as the variables, and the selected responses were CH4 and CO2 conversion, the H2/CO ratio, and coke deposition. The optimal reaction conditions were found to be a CH4/CO2 feed ratio of approximately 3 at 700 °C, producing a large quantity of coke and realizing high CO2 conversion. Furthermore, Raman results showed that the CH4/CO2 ratio and reaction temperature affect the system’s response, particularly the characteristics of the coke produced, which indicates the formation of carbon nanotubes and amorphous carbon.

  19. Jet quenching from QCD evolution

    Science.gov (United States)

    Chien, Yang-Ting; Emerman, Alexander; Kang, Zhong-Bo; Ovanesyan, Grigory; Vitev, Ivan

    2016-04-01

    Recent advances in soft-collinear effective theory with Glauber gluons have led to the development of a new method that gives a unified description of inclusive hadron production in reactions with nucleons and heavy nuclei. We show how this approach, based on the generalization of the DGLAP evolution equations to include final-state medium-induced parton shower corrections for large Q2 processes, can be combined with initial-state effects for applications to jet quenching phenomenology. We demonstrate that the traditional parton energy loss calculations can be regarded as a special soft-gluon emission limit of the general QCD evolution framework. We present phenomenological comparison of the SCETG -based results on the suppression of inclusive charged hadron and neutral pion production in √{sNN }=2.76 TeV lead-lead collisions at the Large Hadron Collider to experimental data. We also show theoretical predictions for the upcoming √{sNN }≃5.1 TeV Pb +Pb run at the LHC.

  20. Rapid production of metallurgical coke by use of a simulated moving bed reactor. Mogi idoso wo mochiita kyusoku shoon ni yoru cokes no jinsoku seizo

    Energy Technology Data Exchange (ETDEWEB)

    Miura, K.; Hayashi, J.; Sano, N. (Kyoto University, Kyoto (Japan). Research Laboratory of CArbonaceous Resources Conversion); Hashimoto, K. (Kyoto University, Kyoto (Japan). Faculty of Engineering); Iwakiri, H. (Kobe Steel, Ltd., Kobe (Japan))

    1992-12-20

    An experiment to manufacture coke with rapid temperature raising was carried out using an equipment simulating a vertical moving bed coke oven. Two kinds of trial manufacturing patterns were tested: Pattern A to raise coal temperature rapidly to about 450[degree]C, which is held for about 20 minutes, and then raised again to 800[degree]C at a rate of about 5[degree]C/min, and pattern B to raise the temperature from about 300[degree]C to 800[degree]C at a rate of about 5[degree]C/min. An experiment on test samples from heavy caking coal (PDH coal) and light caking coal (OP coal) revealed the following results: The PDH coal applied with the pattern A produced in about two hours a coke with quality equivalent to or better than practically used coke; the temperature raising pattern B resulted in no full lump formation even with the PDH coal; according to the temperature raising pattern A, manufacturing coke from the OP coal is impossible; however, if the PDH coal or pitch is mixed with the OP coal, coke may be manufactured. 6 refs., 11 figs., 2 tabs.

  1. Quenching phenomena in natural circulation loop

    Energy Technology Data Exchange (ETDEWEB)

    Umekawa, Hisashi; Ozawa, Mamoru [Kansai Univ., Osaka (Japan); Ishida, Naoki [Daihatsu Motor Company, Osaka (Japan)

    1995-09-01

    Quenching phenomena has been investigated experimentally using circulation loop of liquid nitrogen. During the quenching under natural circulation, the heat transfer mode changes from film boiling to nucleate boiling, and at the same time flux changes with time depending on the vapor generation rate and related two-phase flow characteristics. Moreover, density wave oscillations occur under a certain operating condition, which is closely related to the dynamic behavior of the cooling curve. The experimental results indicates that the occurrence of the density wave oscillation induces the deterioration of effective cooling of the heat surface in the film and the transition boiling regions, which results in the decrease in the quenching velocity.

  2. The Transient Modal Dynamic Analysis of a Coke Tower

    Institute of Scientific and Technical Information of China (English)

    XIE Teng-teng; SUN Tie; XING Ling; ZHANG Su-xiang

    2012-01-01

    Dynamic analysis must be performed when the duration of the applied load is short or if the load is dynamic in nature. Wind load, as a random load, can lead to the vibration of the coke tower. In order to study the influence to the strength of the coke tower by wind, ABAQUS was used to conduct the transient modal dynamic analysis of the wind load. The response of the structure during loading and unloading was mainly observed. The results indicate that, with the effect of wind, the maximal nodal displacement appears at the top of the tower, which is 0.79 mm; while the maximal stress locates at the node around the skirt, the maximum is 3.26 MPa. Both of the displacement and stress cannot cause the failure of the structure. After loading and unloading, the structure engenders vibration along the loading direction. The frequency is 10 Hz, under the effect of external loads, it may easily cause the resonance of the structure, which can cause damage to the structure. So it must be taken into consideration during the process of design and operation.

  3. An additive for a petroleum coke and water suspension

    Energy Technology Data Exchange (ETDEWEB)

    Khiguti, K.; Igarasi, T.; Isimura, Y.; Kharaguti, S.; Tsudzino, T.

    1982-10-18

    An additive to a petroleum coke and water suspension is proposed. The additive consists of a compound with the formula (RCONHCH2C(R')HO(AO)1H, where R is a C1 to C30 unsaturated acyl group, R' is hydrogen, CH3, A is C2 to C4 alkylene, l = 0 to 500, m + n = 0 to 1,000, salt of alkaline metal, salt of ammonium or salt of lower amine and sulfurous ether. The method may be used to produce an aqueous suspension which has a concentration of petroleum coke powder of 50 to 70 percent. The viscosity of the suspension is low, the stability high, no floculation or sedimentation are observed and there is no foam formation. Monoethanolamide, diethanolamide, monoesoproyanolamide and diisopropanolamide of C1 to C30 acid of the fatty series or alkylenoxide (ethylenoxide, propylenoxide, isobutylenoxide and tetrahydrofurane) are used as the (RCONHCH2C(R')HO(AO)1H and a lithium salt

  4. Treatment of coking wastewater by using manganese and magnesium ores

    Energy Technology Data Exchange (ETDEWEB)

    Chen Tianhu; Huang Xiaoming; Pan Min [School of Resources and Environmental Engineering, Hefei University of Technology, Hefei City 230009 (China); Jin Song, E-mail: sjin@uwyo.edu [MWH Americas, 3665 JFK Parkway, Suite 206, Fort Collins, CO 80525 (United States); Department Civil and Architectural Engineering, University of Wyoming, Laramie, WY 82071 (United States); Peng Suchuan [School of Resources and Environmental Engineering, Hefei University of Technology, Hefei City 230009 (China); Fallgren, Paul H. [Western Research Institute, 365 North 9th Street, Laramie, WY 82072 (United States)

    2009-09-15

    This study investigated a wastewater treatment technique based on natural minerals. A two-step process using manganese (Mn) and magnesium (Mg) containing ores were tested to remove typical contaminants from coking wastewater. Under acidic conditions, a reactor packed with Mn ore demonstrated strong oxidizing capability and destroyed volatile phenols, chemical oxygen demand (COD){sub ,} and sulfide from the coking wastewater. The effluent was further treated by using Mg ore to remove ammonium-nitrogen and phosphate in the form of magnesium ammonium phosphate (struvite) precipitates. When pH of the wastewater was adjusted to 1.2, the removal efficiencies for COD, volatile phenol and sulfide reached 70%, 99% and 100%, respectively. During the second step of precipitation, up to 94% of ammonium was removed from the aqueous phase, and precipitated in the form of struvite with phosphorus. The struvite crystals showed a needle-like structure. X-ray diffraction and transmission electron microscopy were used to characterize the crystallized products.

  5. External structure and properties of coke as a function of the petrographic characteristics of the coal mixture

    Energy Technology Data Exchange (ETDEWEB)

    Stankevich, A.S.; Zolotukhin, Yu.A.; Proskuryakov, A.E.; P' yankova, I.S.

    1980-10-01

    Statistical analysis of the results of an investigation of the petrographic composition of carbonisation blends showed that variation in the content of coking components has a marked effect on the porous structure of the coke. As this parameter increases, the quantity of large pores in the coke also increases and the proportion of small and medium-size pores decreases. This leads to a decrease in the mechanical strength of the coke and an increase in reactivity. When selecting carbonisation charges to produce coke of desired quality, it is thus important to take account of the petrographic composition of the blend.

  6. Torus CLAS12-Superconducting Magnet Quench Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kashikhin, V S; Elouadhiri, L; Ghoshal, P K; Kashy, D; Makarov, A; Pastor, O; Quettier, L; Velev, G; Wiseman, M

    2014-06-01

    The JLAB Torus magnet system consists of six superconducting trapezoidal racetrack-type coils assembled in a toroidal configuration. These coils are wound with SSC-36 Nb-Ti superconductor and have the peak magnetic field of 3.6 T. The first coil manufacturing based on the JLAB design began at FNAL. The large magnet system dimensions (8 m diameter and 14 MJ of stored energy) dictate the need for quench protection. Each coil is placed in an aluminum case mounted inside a cryostat and cooled by 4.6 K supercritical helium gas flowing through a copper tube attached to the coil ID. The large coil dimensions and small cryostat thickness drove the design to challenging technical solutions, suggesting that Lorentz forces due to transport currents and eddy currents during quench and various failure scenarios are analyzed. The paper covers the magnet system quench analysis using the OPERA3d Quench code.

  7. Temperature Profiles During Quenches in LHC Superconducting Dipole Magnets Protected by Quench Heaters

    CERN Document Server

    Maroussov, V; Siemko, A

    2000-01-01

    The efficiency of the magnet protection by quench heaters was studied using a novel method which derives the temperature profile in a superconducting magnet during a quench from measured voltage signals. In several Large Hadron Collider single aperture dipole models, temperature profiles and temperature gradients in the magnet coil have been evaluated in the case of protection by different sets of quench heaters and different powering and protection parameters. The influence of the insulation thickness between the quench heaters and the coil has also been considered. The results show clear correlation between the positions of quench heaters, magnet protection parameters and temperature profiles. This study allowed a better understanding of the quench process mechanisms and the efficiency assessment of the different protection schemes.

  8. century drying

    Science.gov (United States)

    Cook, Benjamin I.; Smerdon, Jason E.; Seager, Richard; Coats, Sloan

    2014-11-01

    Global warming is expected to increase the frequency and intensity of droughts in the twenty-first century, but the relative contributions from changes in moisture supply (precipitation) versus evaporative demand (potential evapotranspiration; PET) have not been comprehensively assessed. Using output from a suite of general circulation model (GCM) simulations from phase 5 of the Coupled Model Intercomparison Project, projected twenty-first century drying and wetting trends are investigated using two offline indices of surface moisture balance: the Palmer Drought Severity Index (PDSI) and the Standardized Precipitation Evapotranspiration Index (SPEI). PDSI and SPEI projections using precipitation and Penman-Monteith based PET changes from the GCMs generally agree, showing robust cross-model drying in western North America, Central America, the Mediterranean, southern Africa, and the Amazon and robust wetting occurring in the Northern Hemisphere high latitudes and east Africa (PDSI only). The SPEI is more sensitive to PET changes than the PDSI, especially in arid regions such as the Sahara and Middle East. Regional drying and wetting patterns largely mirror the spatially heterogeneous response of precipitation in the models, although drying in the PDSI and SPEI calculations extends beyond the regions of reduced precipitation. This expansion of drying areas is attributed to globally widespread increases in PET, caused by increases in surface net radiation and the vapor pressure deficit. Increased PET not only intensifies drying in areas where precipitation is already reduced, it also drives areas into drought that would otherwise experience little drying or even wetting from precipitation trends alone. This PET amplification effect is largest in the Northern Hemisphere mid-latitudes, and is especially pronounced in western North America, Europe, and southeast China. Compared to PDSI projections using precipitation changes only, the projections incorporating both

  9. The Release of Trace Elements in the Process of Coal Coking

    Directory of Open Access Journals (Sweden)

    Jan Konieczyński

    2012-01-01

    Full Text Available In order to assess the penetration of individual trace elements into the air through their release in the coal coking process, it is necessary to determine the loss of these elements by comparing their contents in the charge coal and in coke obtained. The present research covered four coke oven batteries differing in age, technology, and technical equipment. By using mercury analyzer MA-2 and the method of ICP MS As, Be, Cd, Co, Hg, Mn, Ni, Se, Sr, Tl, V, and Zn were determined in samples of charge coal and yielded coke. Basing on the analyses results, the release coefficients of selected elements were determined. Their values ranged from 0.5 to 94%. High volatility of cadmium, mercury, and thallium was confirmed. The tests have shown that although the results refer to the selected case studies, it may be concluded that the air purity is affected by controlled emission occurring when coke oven batteries are fired by crude coke oven gas. Fugitive emission of the trace elements investigated, occurring due to coke oven leaks and openings, is small and, is not a real threat to the environment except mercury.

  10. Formation of coke in thermal cracking of jet fuel under supercritical conditions

    Institute of Scientific and Technical Information of China (English)

    Yuhong ZHU; Caixiang YU; Zimu LI; Zhentao MI; Xiangwen ZHANG

    2008-01-01

    Continuous-flow reactor experiments were carried out to study coke formation from thermal crack-ing of home-made jet fuel RP-3 under supercritical con-ditions. The mechanism and precursor of coke forming were analyzed. The starting cracking temperature of RP-3 fuel was determined to be 471.8℃ by differential scan-ning calorimetry (DSC). Temperature-programmed oxidation and scanning electron microscopy (SEM) characterizations of the stressed tubes showed that there are three different coke species including chemisorbed carbon, amorphous carbon and filamentous coke in the solid deposits. More than 90% of coke deposits are carried away by the supercritical fluid, which has strong capabilities of extraction for coke deposits and their pre-cursors. There were 17.1 wt-% of iron and 11.1 wt-% of chromium found on the coke surface detected by energy dispersive spectroscopy (EDS) which suggests carbure-tion on alloy. RP-3 fuel and its cracking liquids were analyzed by GC-MS,which showed that the content of alkyl benzene and alkyl naphthalene increased evidently in cracking liquids.

  11. Distribution, partition and removal of polycyclic aromatic hydrocarbons (PAHs) during coking wastewater treatment processes.

    Science.gov (United States)

    Zhang, Wanhui; Wei, Chaohai; An, Guanfeng

    2015-05-01

    In this study, we report the performance of a full-scale conventional activated sludge (A-O1-O2) treatment in eliminating polycyclic aromatic hydrocarbons (PAHs). Both aqueous and solid phases along with the coking wastewater treatment processes were analyzed for the presence of 18 PAHs. It was found that the target compounds occurred widely in raw coking wastewater, treated effluent and sludge samples. In the coking wastewater treatment system, 4-5 ring PAHs were the dominant compounds, while 4 rings PAHs predominated in the sludge samples. Over 98% of the PAH removal was achieved in the coking wastewater treatment plant (WWTP), with the total concentration of PAHs being 21.3 ± 1.9 μg L(-1) in the final effluent. During the coking wastewater treatment processes, the association of the lower molecular weight PAH with suspended solids was generally less than 60%, while the association of higher molecular weight PAHs was greater than 90%. High distribution efficiencies (Kdp and Kds) were found, suggesting that adsorption was the potential removal pathway of PAHs. Finally, the mass balances of PAHs in various stages of the coking WWTP were obtained, and the results indicated that adsorption to sludge was the main removal pathway for PAHs in the coking wastewater treatment processes.

  12. The surprising inefficiency of dwarf satellite quenching

    CERN Document Server

    Wheeler, Coral; Cooper, Michael C; Boylan-Kolchin, Mike; Bullock, James S

    2014-01-01

    We study dwarf satellite galaxy quenching using observations from the Geha et al. (2012) NSA/SDSS catalog together with LCDM cosmological simulations to facilitate selection and interpretation. We show that fewer than 30% of dwarfs (M* ~ 10^8.5-10^9.5 Msun) identified as satellites within massive host halos (Mhost ~ 10^12.5-10^14 Msun) are quenched, in spite of the expectation from simulations that half of them should have been accreted more than 6 Gyr ago. We conclude that whatever the action triggering environmental quenching of dwarf satellites, the process must be highly inefficient. We investigate a series of simple, one-parameter quenching models in order understand what is required to explain the low quenched fraction and conclude that either the quenching timescale is very long (> 9.5 Gyr, a "slow starvation" scenario) or that the environmental trigger is not well matched to accretion within the virial volume. We discuss these results in light of the fact that most of the low mass dwarf satellites in ...

  13. Dry cell battery poisoning

    Science.gov (United States)

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  14. Dependence of optical structure of coke from black coal on petrologic peculiarities of the coal

    Energy Technology Data Exchange (ETDEWEB)

    Proskuryakov, A.E.; Stankevich, A.S.; Podchishchaeva, N.I.; Shkoller, M.B.

    1988-01-01

    Analyzes factors that influence optical structure of coke from Kuzbass black coal. An optical microscope (magnification 800-2,000 times) was used. On the basis of investigations 8 types of optical structures in coke were determined: an isotropic structure, fine grain structure, medium grain structure, large grain structure, fibre-like structure, inertinite structure and a relict structure. The following criteria for determining optical structures are used: optical character of coke matter, grain size, grain geometry, microlites and primary structure. Using regression analysis, dependence of the optical structures on the following indices were derived: vitrinite reflectivity, vitrinite content and reduction degree. 12 refs.

  15. Prevention of difficulties due to coke deposits in in-situ combustion developments

    Energy Technology Data Exchange (ETDEWEB)

    Condrachi, A.; Teisanu, G.; Paraschiv, R. [PETRON R. A.- ICPT Campina, (Romania); Platon, A. [ISERP S. A. - Ploiesti, (Romania)

    1993-12-31

    Difficulties created by coke deposits in the bridging in the drainage area of producing wells, and coke deposits on bottomhole equipment, were described. Both of these types of problems tend to increase production costs, and consequently the cost of the extracted oil. The essential nature of the mechanisms and parameters that are responsible for the formation and burning of coke within favorable limits and utilization of appropriate equipment that have been found useful in partial or complete elimination of these difficulties, were also described. 44 refs., 3 figs.

  16. Secondary Heating Under Quenching Cooling of Aluminum Alloys

    Science.gov (United States)

    Tsukrov, S. L.; Ber, L. B.

    2017-07-01

    Variants of secondary heating of aluminum alloys are considered, i.e., under quenching of plates in a water tank or on a horizontal quenching unit with water jet cooling, under continuous quenching of strips, and under quenching of tubes in vertical furnaces. Recommendation are given for removal or substantial reduction of the intensity of secondary heating under industrial conditions.

  17. A device for determining the regularity factor of coke yield

    Energy Technology Data Exchange (ETDEWEB)

    Pankrat' ev, O.N.; Bannikov, L.S.; Grishin, S.P.; Parfenov, G.I.

    1982-01-01

    A device which determines the regularity factor of coke yield, which contains a furnace output monitoring unit, which is connected to the meter's input and an indicator, also contains a programmer, a comparator, a second meter, a multiplier and a divider to increase the efficiency and the reliability of information and to reduce manual labor. Here, the first output from the programmer is connected to the multiplier's input while the second output is connected to the initial inputs of the divider and the comparator, the second input of which is connected to the first indicator's output, while the output is connected to the second indicator's input, the output of which is connected to the divider's second input; the output of the divider is connected to the multiplier's second input and to the indicator which is connected to the multiplier's output.

  18. Synthesis of carbon molecular sieves by activation and coke deposition

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, S.N.; Patwardhan, S.R.; Vijayalakshmi, S.; Gandadhar, B. (Indian Institute of Technology, Bombay (India). Dept. of Chemical Engineering)

    1993-04-01

    Carbon molecular sieves were synthesized from indigenous bituminous coal and coconut shell. After preliminary treatment, these materials were subjected to steam or carbon dioxide activation in the range 500-900[degree]C. In other experiments the raw materials were partly air-oxidized at [approximately] 200[degree]C, mixed with binder and extruded to cylindrical pellets, which were subjected to coke deposition by cracking of methane in the range 750-780[degree]C for 5-14 min. All the products were characterized by analysis of kinetic and equilibrium adsorption data. The molecular sieve performance was judged by the O[sub 2]/N[sub 2] uptake ratio. The best carbon molecular sieves, obtained by methane cracking at 780[degree]C at a flow of 100 ml min[sup -1] had an uptake ratio of 2.667. 11 refs., 7 figs., 5 tabs.

  19. Quench Protection of DI-BSCCO Coil

    Science.gov (United States)

    Yamaguchi, T.; Ueno, E.; Kato, T.; Hayashi, K.

    Quench protection is one of the most important requirements for the practical application of high-temperature-superconducting (HTS) coils. Quench protection requires that early detection of a developing quench event is followed by rapid reduction of the operating current. However, such quench detection is very difficult because HTS wire produces heat only locally due to the very slow propagation velocity of a normal zone. Excellent high voltage insulation performance is required if the current is to be reduced rapidly in a large-scale superconducting application with very large inductance. Thus it is important to investigate the behavior of coils with various decay time constants, and to detect voltages on very short time scales. This goal remains to be achieved. In the present study we built test coil and a full-scale pole coil for a 20 MW motor for use in experiments on quench protection, and parameterized the relation between the decay time constant and the detecting voltage, using a conventional balance circuit to detect the quench, which was generated by gradually raising the temperature of the coils. The results verify that a balance circuit can be used for quench detection. For example, when the current decay time constant is 4 seconds, the test coil can be protected even with a detecting voltage of 0.15 volts, despite a significant heat production rate of 126 W. We also confirmed that the full-scale pole coil, with a decay time constant of 20 seconds, can be protected with a detecting voltage of 0.06 V.

  20. Effects of quenching and partial quenching on QCD penguin matrix elements

    NARCIS (Netherlands)

    Golterman, Maarten; Pallante, Elisabetta

    2002-01-01

    We point out that chiral transformation properties of penguin operators change in the transition from unquenched to (partially) quenched QCD. The way in which this affects the lattice determination of weak matrix elements can be understood in the framework of (partially) quenched chiral perturbation

  1. Quench absorption coils: a quench protection concept for high-field superconducting accelerator magnets

    Science.gov (United States)

    Mentink, M.; Salmi, T.

    2017-06-01

    A quench protection concept based on coupled secondary coils is studied for inductively transferring energy out of a quenching superconducting dipole and thus limiting the peak hotspot temperature. So-called ‘quench absorption coils’ are placed in close proximity to the superconducting coils and are connected in series with a diode for the purpose of preventing current transformation during regular operation. During a quench, current is then transformed into the quench absorption coils so that a significant fraction of the stored magnetic energy is dissipated in the these coils. Numerical calculations are performed to determine the impact of such a concept and to evaluate the dimensions of the quench absorption coils needed to obtain significant benefits. A previously constructed 15 T Nb3Sn block coil is taken as a reference layout. Finite-element calculations are used to determine the combined inductive and thermal response of this system and these calculations are validated with a numerical model using an adiabatic approximation. The calculation results indicate that during a quench the presence of the quench absorption coils reduces the energy dissipated in the superconducting coils by 45% and reduces the hotspot temperature by over 100 K. In addition, the peak resistive voltage over the superconducting coils is significantly reduced. This suggests that this concept may prove useful for magnet designs in which the hotspot temperature is a design driver.

  2. Dry Mouth

    Science.gov (United States)

    ... Use a fluoride rinse or brush-on fluoride gel before bedtime. See your dentist at least twice yearly to have your teeth examined and plaque removed, to help prevent tooth decay. Several herbal remedies have been used historically to treat dry ...

  3. Acrylamide-quenching of Rhizomucor miehei lipase.

    Science.gov (United States)

    Stobiecka, Agnieszka

    2005-07-01

    Steady-state and time-resolved fluorescence-quenching measurements have been performed to study multitryptophan lipase from filamentous fungus Rhizomucor miehei. Using the steady-state acrylamide fluorescence quenching data and the fluorescence-quenching-resolved-spectra (FQRS) method, the total emission spectrum of native ("closed-lid") lipase has been decomposed into two distinct spectral components accessible to acrylamide. According to FQRS analysis, more quenchable component has a maximum of fluorescence emission at about 352 nm whereas less quenchable component emits at about 332 nm. The redder component participates in about 60-64% of the total lipase fluorescence and may be characterized by the dynamic and static quenching constants equal to K(1) = 3.75 M(-1) and V(1) = 1.12 M(-1), respectively. The bluer component is quenchable via dynamic mechanism with K(2) = 1.97 M(-1). Significant difference in the values of acrylamide bimolecular rate quenching constants estimated for redder and bluer component (i.e., k(q) = 1.2 x 10 (9) M(-1)s (-1) vs. k(q) = 4.3 x 10(8) M(-1) s(-1), respectively), suggests that tryptophan residues in fungal lipase are not uniformly exposed to the solvent.

  4. Topological blocking in quantum quench dynamics

    Science.gov (United States)

    Kells, G.; Sen, D.; Slingerland, J. K.; Vishveshwara, S.

    2014-06-01

    We study the nonequilibrium dynamics of quenching through a quantum critical point in topological systems, focusing on one of their defining features: ground-state degeneracies and associated topological sectors. We present the notion of "topological blocking," experienced by the dynamics due to a mismatch in degeneracies between two phases, and we argue that the dynamic evolution of the quench depends strongly on the topological sector being probed. We demonstrate this interplay between quench and topology in models stemming from two extensively studied systems, the transverse Ising chain and the Kitaev honeycomb model. Through nonlocal maps of each of these systems, we effectively study spinless fermionic p-wave paired topological superconductors. Confining the systems to ring and toroidal geometries, respectively, enables us to cleanly address degeneracies, subtle issues of fermion occupation and parity, and mismatches between topological sectors. We show that various features of the quench, which are related to Kibble-Zurek physics, are sensitive to the topological sector being probed, in particular, the overlap between the time-evolved initial ground state and an appropriate low-energy state of the final Hamiltonian. While most of our study is confined to translationally invariant systems, where momentum is a convenient quantum number, we briefly consider the effect of disorder and illustrate how this can influence the quench in a qualitatively different way depending on the topological sector considered.

  5. Effect of injecting inert particles on coking prohibition and particle velocity uniformization in downer reactors

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J.Y.; Zhu, Y.; Tian, Y.J.; Xie, K.C. [Fuzhou University, Fuzhou (China). Inst. of Chemical Engineering & Technology

    2007-02-15

    The coking observation and particle flow behaviour in both thermal plasma and cold plexiglas downers were investigated in a binary particle system formed by injecting coarse inert particles (carrying coke away and scouring wall) and fine coal powders into the downer reactor. The results demonstrate that this scheme is a rational selection to prevent coking on downer walls and improve particle velocity distribution along the radial direction. When injected coarse particles mixed with fine powders in downers, the fluctuation of local particle velocity in the radial direction becomes smaller and two peaks in the radial distribution of local particle velocity occur due to the improved dispersing character and flow structure, which are beneficial to the thermo-plasma coal cracking reaction and coking prevention.

  6. Pyrolysis kinetics of coking coal mixed with biomass under non-isothermal and isothermal conditions.

    Science.gov (United States)

    Jeong, Ha Myung; Seo, Myung Won; Jeong, Sang Mun; Na, Byung Ki; Yoon, Sang Jun; Lee, Jae Goo; Lee, Woon Jae

    2014-03-01

    To investigate the kinetic characteristics of coking coal mixed with biomass during pyrolysis, thermogravimetric (TG) and thermo-balance reactor (TBR) analyses were conducted under non-isothermal and isothermal condition. Yellow poplar as a biomass (B) was mixed with weak coking coal (WC) and hard coking coal (HC), respectively. The calculated activation energies of WC/B blends were higher than those of HC/B blends under non-isothermal and isothermal conditions. The coal/biomass blends show increased reactivity and decreased activation energy with increasing biomass blend ratio, regardless of the coking properties of the coal. The different char structures of the WC/B and HC/B blends were analyzed by BET and SEM.

  7. The New Method of XRD Measurement of the Degree of Disorder for Anode Coke Material

    Directory of Open Access Journals (Sweden)

    Zhuo Zhang

    2017-01-01

    Full Text Available Quantitative analysis by X-ray powder diffraction of two cokes (pitch coke and petroleum coke shows that their crystal structure changed with increasing temperature. The crystal data processing of the crystallization degree of disorder is used with further improvement of the proposed microcrystalline-stacking fault calculation method. With this improvement it is now possible to obtain the degree of stacking disorder of two cokes applied as anode materials at different graphitization temperatures. Raman spectroscopy verified the accuracy of this method, which is more reliable than the crystal structure refinement using the d002 method. This paper provides the theoretical analysis and interpretation of the relationship between the microstructure model of the material and quantitative data, discharge capacity, and the first charge-discharge efficiency.

  8. Coke formation on HFAU and HEMT zeolites. Influence of the reaction temperature and propene pressure

    Science.gov (United States)

    Doka Nassionou, G. A.; Magnoux, P.; Guisnet, M.

    1999-02-01

    The formation of coke from propene (Pp = 1.3 kPa and 13 kPa) was investigated on HFAU and HEMT zeolites in a microbalance for temperatures ranging from 120 °C to 450 °C. For both zeolites, the greater the propene pressure and the lower the temperature the faster the initial coke formation. However for high propene pressure, initial coke formation is faster with HEMT zeolite. This can be related to the stronger acidity of the HEMT sample. For low propene pressure and after 420 minutes of coking, a minimum in coke is observed for T = 350 ^circC, which can be related to the difference between the rate of formation and the rate of retention of coke molecules. At low temperature, due to their low volatility, oligomers are easily formed and retained in the zeolite pores. These molecules can be totally eliminated by an adequate thermal treatment in vacuum. At higher temperature, only aromatic or polyaromatic compounds which present a size larger than the pore apertures can be retained in the cavities of the zeolites. The greater the reaction time, the faster the retention. Whatever the reaction temperature, coke molecules are more homogeneously distributed in the HEMT crystallites than in those of HFAU samples. For this latter zeolite coke molecules are preferentially formed in the cavities located near the outer surface of the crystallites (shell coking). La formation de coke à partir du propène (Pp = 1,3 et 13 kPa) a été étudiée en microbalance sur zéolithes HFAU et HEMT dans une gamme de température variant de 120 à 450°C. La vitesse initiale de formation de coke dépend de la pression du propène, de la température et également de la zéolithe. Ainsi, pour une forte pression en propène, la vitesse initiale de formation de coke est toujours plus importante sur HEMT que sur HFAU. Ceci est à relier à la plus grande acidité et à la présence de sites acides plus forts sur HEMT. Après 420 minutes de réaction, et pour une faible pression en propène le

  9. modelling and modelling and simulation of coking in the riser of an ...

    African Journals Online (AJOL)

    eobe

    2, 3DEPARTMENT OF CHEMICAL ENGINEERING, AHMADU BELLO UNIVERSITY, NIGERIA. E-mail addresses: ... ass transfer resistance was incorporated in the reactor model to ... by predicting catalyst coke content as a function of reaction.

  10. Influence of carbonization conditions on micro-pore structure of foundry formed coke produced with char

    Energy Technology Data Exchange (ETDEWEB)

    Jun Qiao; Jianjun Wu; Jingru Zu; Zhiyuan Gao; Guoli Zhou

    2009-07-01

    There are few studies on coke's micro-pore structure in recent years, however, micro-pore structure of foundry coke determines its macroscopically quality index and reactivity in cupola furnace. Effect of such factors on micro-pore structure were investigated under different carbonization conditions with certain ratio of raw materials and material forming process in this article as charging temperature (A); braised furnace time (B); heating rate of the first stage (C)and the second stage (D) and holding time of ultimate temperature (E). Research showed that charging temperature was the most influential factor on the coke porosity, pore volume, pore size and specific surface area. It is suggested that formation of plastic mass and releasing rate of volatile during carbonization period are two main factors on microstructure of foundry coke while charging temperature contributes most to the above factors. 6 refs., 4 figs., 9 tabs.

  11. Temperature-programmed oxidation of coked noble metal catalysts after autothermal reforming of n-hexadecane

    Energy Technology Data Exchange (ETDEWEB)

    Kauppi, E.I.; Linnekoski, J.A.; Krause, A.O.I.; Veringa Niemelae, M.K. [Aalto University, School of Science and Technology, Department of Biotechnology and Chemical Technology, Research Group Industrial Chemistry, P.O. Box 16100, FI-00076 Aalto (Finland); Kaila, R.K. [VTT Technical Research Centre of Finland, Biologinkuja 7, Espoo, P.O. Box 1001, FI-02044 VTT (Finland)

    2010-08-15

    Autothermal reforming (ATR) of n-hexadecane was carried out on zirconia-supported mono- and bimetallic noble metal (Rh, Pt) catalysts at 600, 700, and 800 C. After ATR, the reactivity of coke deposits (2.8-9.9 wt%) on the catalysts was investigated by temperature-programmed oxidation (TPO). Analysis of the results obtained from ATR and TPO experiments at various temperatures and on the different catalysts gave information on the reaction conditions where the detrimental coke can be minimized and allows estimating the nature of carbon deposits. H{sub 2} production increased with temperature on the tested Rh-containing catalysts and the ZrO{sub 2} support, but decreased as a function of temperature on the Pt catalyst. The formation of coke was least at 800 C, evidently due to the intensifying reaction of carbon and steam with increasing temperature, as well as to the better activity of the catalysts. The amount of coke formed was highest at 700 C. Comparison of the TPO profiles obtained for the monometallic Rh and Pt catalysts with the bimetallic RhPt revealed differences in the nature of carbon deposits on their surface. At 600 C, the coke formed on the monometallic Rh and Pt catalysts was located mostly on the support, whereas on the bimetallic RhPt catalyst the formation of this type of coke was suppressed. The bimetallic RhPt catalyst also exhibited better tolerance toward coking at 700 C. Therefore, although the selectivity toward hydrogen was not related to the amount of coke formed, the deactivation patterns differed on the mono- and bimetallic catalysts. (author)

  12. Chinese Standards on Refractories Fireclay Brick and Semi-silica Brick for Coke Oven

    Institute of Scientific and Technical Information of China (English)

    Wang Jing

    2009-01-01

    @@ 1 Scope This standard specifies the technical requirements,test methods,quality appraisal procedure,packing,transportation,storage,and quality certificate of fireclay brick and semi-silica brick for coke oven. This standard is applicable to the fireclay brick and semi-silica brick for coke oven,and the bricks for inner linings of carbon furnace,gas generator and shaft furnace.

  13. Mixtures of Steel-Making Slag and Carbons as Catalyst for Microwave-Assisted Dry Reforming of CH4

    Institute of Scientific and Technical Information of China (English)

    Jose M. BERMUDEZ; Beatriz FIDALGO; Ana ARENILLAS; J. Angel MENENDEZ

    2012-01-01

    The use of steel-making slag as catalysts for microwave-assisted dry reforming of CH4 was studied.Two carbon materials (an activated carbon and a metallurgical coke),mixtures of the carbon materials and Fe-rich slag,and mixtures of the carbon materials and Ni/Al2O3 were tested as catalysts.The mixtures of slag with carbons gave rise to higher and steadier conversions than those achieved over the carbon materials alone.In addition,the use of the metallurgical coke mixed with metal-rich catalysts gave rise to remarkable results.Thus,no CH4 and CO2 conversions were achieved when coke was used alone,whereas high conversions were obtained when it was mixed with the metal-rich catalysts.

  14. Thermal quench at finite 't Hooft coupling

    Directory of Open Access Journals (Sweden)

    H. Ebrahim

    2016-03-01

    Full Text Available Using holography we have studied thermal electric field quench for infinite and finite 't Hooft coupling constant. The set-up we consider here is D7-brane embedded in (α′ corrected AdS-black hole background. It is well-known that due to a time-dependent electric field on the probe brane, a time-dependent current will be produced and it will finally relax to its equilibrium value. We have studied the effect of different parameters of the system on equilibration time. As the most important results, for massless fundamental matter, we have observed a universal behaviour in the rescaled equilibration time in the very fast quench regime for different values of the temperature and α′ correction parameter. It seems that in the slow quench regime the system behaves adiabatically. We have also observed that the equilibration time decreases in finite 't Hooft coupling limit.

  15. Dynamical quenching of tunneling in molecular magnets

    Energy Technology Data Exchange (ETDEWEB)

    José Santander, María, E-mail: maria.jose.noemi@gmail.com [Recursos Educativos Quántica, Santiago (Chile); Departamento de Física, Universidad de Santiago de Chile and CEDENNA, Avda. Ecuador 3493, Santiago (Chile); Nunez, Alvaro S., E-mail: alnunez@dfi.uchile.cl [Departamento de Física, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Casilla 487-3, Santiago (Chile); Roldán-Molina, A. [Instituto de Física, Pontificia Universidad Católica de Valparaíso, Avenida Universidad 330, Curauma, Valparaíso (Chile); Troncoso, Roberto E., E-mail: r.troncoso.c@gmail.com [Centro para el Desarrollo de la Nanociencia y la Nanotecnología, CEDENNA, Avda. Ecuador 3493, Santiago 9170124 (Chile); Departamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680, Valparaíso (Chile)

    2015-12-15

    It is shown that a single molecular magnet placed in a rapidly oscillating magnetic field displays the phenomenon of quenching of tunneling processes. The results open a way to manipulate the quantum states of molecular magnets by means of radiation in the terahertz range. Our analysis separates the time evolution into slow and fast components thereby obtaining an effective theory for the slow dynamics. This effective theory presents quenching of the tunnel effect, in particular, stands out its difference with the so-called coherent destruction of tunneling. We support our prediction with numerical evidence based on an exact solution of Schrödinger's equation. - Highlights: • Single molecular magnets under rapidly oscillating magnetic fields is studied. • It is shown that this system displays the quenching of tunneling processes. • Our findings provide a control of quantum molecular magnets via terahertz radiation.

  16. 煤气化黑水作为石油焦浆稳定剂的实验研究%Experimental study on black water of coal gasification as stabilizer of petroleum coke-water slurry

    Institute of Scientific and Technical Information of China (English)

    贾嘉; 展秀丽; 周志杰; 王辅臣

    2011-01-01

    Petroleum coke has higher calorific value and lower price compared with coal. It has great advantages that petroleum coke-water slurry is used to prepare syngas. The first step of gasification with petroleum coke-water slurry is to prepare the coke-water slurry. With chilling black water of coal gasification as stabilizer of petroleum coke-water slurry, it can not only save the cost of stabilizer, but also resolve the problems of treating black water and environmental pollution. The way of producing petroleum coke-water slurry is dry grinding and humid mixing; the adding ratio of black water to deionized water is gradually increased; and the viscosity of the slurry was determined when the shear rate was 100 s-1. The liquidity and stable time of the slurry were observed. The effect of black water as stabilizer on the slurry properties of petroleum coke-water was investigated. The results show that black water can effectively improve the stability and yield stress of petroleum coke-water slurry. Petroleum coke added with black water can produce the coke-water slurry with solid mass fraction as high as 73% , and its stability, viscosity and liquidity can satisfy the demand of slurry for gasification in industry.%石油焦比煤具有更高的热值,同时价格低廉,利用石油焦浆气化制备合成气具有很大的优势.石油焦浆气化的第1步是制备水焦浆,采用煤气化黑水作为石油焦浆的稳定剂,不仅节约了稳定剂的成本,还解决了黑水的处理和对环境的污染问题.文中通过逐步提高石油焦浆制备过程中黑水与去离子水的添加比例,采用干磨湿混的方式制浆,测定了石油焦浆在剪切应力为100 s-1时的黏度,并观察其流动性及稳定时间等各项指标,考察了黑水对石油焦浆稳定性的影响.结果表明:黑水能够有效提高石油焦浆的稳定性,提高屈服应力.石油焦添加黑水最高可制备出固体颗粒质量分数为73%的水焦浆,其稳定性和

  17. Volatiles production from the coking of coal; Sekitan no netsubunkai ni okeru kihatsubun seisei

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Y.; Saito, H.; Inaba, A. [National Institute for Resources and Environment, Tsukuba (Japan)

    1996-10-28

    In order to simplify the coke manufacturing process, a coke production mechanism in coal pyrolysis was discussed. Australian bituminous coal which can produce good coke was used for the discussion. At a temperature raising rate of 50{degree}C per minute, coal weight loss increases monotonously. However, in the case of 3{degree}C, the weight loss reaches a peak at a maximum ultimate temperature of about 550{degree}C. The reaction mechanism varies with the temperature raising rates, and in the case of 50{degree}C per minute, volatiles other than CO2 and propane increased. Weight loss of coal at 3{degree}C per minute was caused mainly by methane production at 550{degree}C or lower. When the temperature is raised to 600{degree}C, tar and CO2 increased, and so did the weight loss. Anisotropy was discerned in almost of all coke particles at 450{degree}C, and the anisotropy became remarkable with increase in the maximum ultimate temperature. Coke and volatiles were produced continuously at a temperature raising rate of 50{degree}C per minute, and at 3{degree}C per minute, the production of the coke and volatiles progressed stepwise as the temperature has risen. 7 refs., 6 figs.

  18. Catalytic conversion of lignin pyrolysis model compound- guaiacol and its kinetic model including coke formation

    Science.gov (United States)

    Zhang, Huiyan; Wang, Yun; Shao, Shanshan; Xiao, Rui

    2016-11-01

    Lignin is the most difficult to be converted and most easy coking component in biomass catalytic pyrolysis to high-value liquid fuels and chemicals. Catalytic conversion of guaiacol as a lignin model compound was conducted in a fixed-bed reactor over ZSM-5 to investigate its conversion and coking behaviors. The effects of temperature, weight hourly space velocity (WHSV) and partial pressure on product distribution were studied. The results show the maximum aromatic carbon yield of 28.55% was obtained at temperature of 650 °C, WHSV of 8 h‑1 and partial pressure of 2.38 kPa, while the coke carbon yield was 19.55%. The reaction pathway was speculated to be removing methoxy group to form phenols with further aromatization to form aromatics. The amount of coke increased with increasing reaction time. The surface area and acidity of catalysts declined as coke formed on the acid sites and blocked the pore channels, which led to the decrease of aromatic yields. Finally, a kinetic model of guaiacol catalytic conversion considering coke deposition was built based on the above reaction pathway to properly predict product distribution. The experimental and model predicting data agreed well. The correlation coefficient of all equations were all higher than 0.90.

  19. Acute toxicity and chemical evaluation of coking wastewater under biological and advanced physicochemical treatment processes.

    Science.gov (United States)

    Dehua, Ma; Cong, Liu; Xiaobiao, Zhu; Rui, Liu; Lujun, Chen

    2016-09-01

    This study investigated the changes of toxic compounds in coking wastewater with biological treatment (anaerobic reactor, anoxic reactor and aerobic-membrane bioreactor, A1/A2/O-MBR) and advanced physicochemical treatment (Fenton oxidation and activated carbon adsorption) stages. As the biological treatment stages preceding, the inhibition effect of coking wastewater on the luminescence of Vibrio qinghaiensis sp. Nov. Q67 decreased. Toxic units (TU) of coking wastewater were removed by A1/A2/O-MBR treatment process, however approximately 30 % TU remained in the biologically treated effluent. There is a tendency that fewer and fewer residual organic compounds could exert equal acute toxicity during the biological treatment stages. Activated carbon adsorption further removed toxic pollutants of biologically treated effluent but the Fenton effluent increased acute toxicity. The composition of coking wastewater during the treatment was evaluated using the three-dimensional fluorescence spectra, gas chromatography-mass spectrometry (GC-MS). The organic compounds with high polarity were the main cause of acute toxicity in the coking wastewater. Aromatic protein-like matters in the coking wastewater with low biodegradability and high toxicity contributed mostly to the remaining acute toxicity of the biologically treated effluents. Chlorine generated from the oxidation process was responsible for the acute toxicity increase after Fenton oxidation. Therefore, the incorporation of appropriate advanced physicochemical treatment process, e.g., activated carbon adsorption, should be implemented following biological treatment processes to meet the stricter discharge standards and be safer to the environment.

  20. Discerning the Location and Nature of Coke Deposition from Surface to Bulk of Spent Zeolite Catalysts

    Science.gov (United States)

    Devaraj, Arun; Vijayakumar, Murugesan; Bao, Jie; Guo, Mond F.; Derewinski, Miroslaw A.; Xu, Zhijie; Gray, Michel J.; Prodinger, Sebastian; Ramasamy, Karthikeyan K.

    2016-11-01

    The formation of carbonaceous deposits (coke) in zeolite pores during catalysis leads to temporary deactivation of catalyst, necessitating regeneration steps, affecting throughput, and resulting in partial permanent loss of catalytic efficiency. Yet, even to date, the coke molecule distribution is quite challenging to study with high spatial resolution from surface to bulk of the catalyst particles at a single particle level. To address this challenge we investigated the coke molecules in HZSM-5 catalyst after ethanol conversion treatment by a combination of C K-edge X-ray absorption spectroscopy (XAS), 13C Cross polarization-magic angle spinning nuclear magnetic resonance (CP-MAS NMR) spectroscopy, and atom probe tomography (APT). XAS and NMR highlighted the aromatic character of coke molecules. APT permitted the imaging of the spatial distribution of hydrocarbon molecules located within the pores of spent HZSM-5 catalyst from surface to bulk at a single particle level. 27Al NMR results and APT results indicated association of coke molecules with Al enriched regions within the spent HZSM-5 catalyst particles. The experimental results were additionally validated by a level-set–based APT field evaporation model. These results provide a new approach to investigate catalytic deactivation due to hydrocarbon coking or poisoning of zeolites at an unprecedented spatial resolution.

  1. Discrete Element Method Modeling of the Rheological Properties of Coke/Pitch Mixtures

    Directory of Open Access Journals (Sweden)

    Behzad Majidi

    2016-05-01

    Full Text Available Rheological properties of pitch and pitch/coke mixtures at temperatures around 150 °C are of great interest for the carbon anode manufacturing process in the aluminum industry. In the present work, a cohesive viscoelastic contact model based on Burger’s model is developed using the discrete element method (DEM on the YADE, the open-source DEM software. A dynamic shear rheometer (DSR is used to measure the viscoelastic properties of pitch at 150 °C. The experimental data obtained is then used to estimate the Burger’s model parameters and calibrate the DEM model. The DSR tests were then simulated by a three-dimensional model. Very good agreement was observed between the experimental data and simulation results. Coke aggregates were modeled by overlapping spheres in the DEM model. Coke/pitch mixtures were numerically created by adding 5, 10, 20, and 30 percent of coke aggregates of the size range of 0.297–0.595 mm (−30 + 50 mesh to pitch. Adding up to 30% of coke aggregates to pitch can increase its complex shear modulus at 60 Hz from 273 Pa to 1557 Pa. Results also showed that adding coke particles increases both storage and loss moduli, while it does not have a meaningful effect on the phase angle of pitch.

  2. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Written By: Kierstan Boyd Reviewed By: ... your eyes do not produce enough tears, it is called dry eye. Dry eye is also when ...

  3. Quench in high temperature superconductor magnets

    CERN Document Server

    Schwartz, J

    2013-01-01

    High field superconducting magnets using high temperature superconductors are being developed for high energy physics, nuclear magnetic resonance and energy storage applications. Although the conductor technology has progressed to the point where such large magnets can be readily envisioned, quench protection remains a key challenge. It is well-established that quench propagation in HTS magnets is very slow and this brings new challenges that must be addressed. In this paper, these challenges are discussed and potential solutions, driven by new technologies such as optical fiber based sensors and thermally conducting electrical insulators, are reviewed.

  4. Quench propagation analysis in adiabatic superconducting windings

    Energy Technology Data Exchange (ETDEWEB)

    Ishiyama, A.; Matsumura, H.; Takita, W. (Dept. of Electrical Engineering, Waseda Univ., Tokyo (JP)); Iwasa, Y (Massachusetts Inst. of Tech., Cambridge, MA (United States). Francis Bitter National Magnet Lab.)

    1991-03-01

    This paper reports the basic postulate of the author's quench simulation code, developed to analyze normal-zone propagation in adiabatic magnets which is the code's computation may be immensely simplified without sacrifice in accuracy by aggregating all thermal properties of the winding affecting normal-zone propagation into a single parameter of the transverse quench velocity. In order to verify this postulate, a finite element method (FEM) analysis has been applied to solve the temporal and spatial evolution of temperature within a section of an adiabatic magnet winding.

  5. Event-Shape Engineering and Jet Quenching

    CERN Document Server

    Christiansen, Peter

    2016-01-01

    Event-Shape Engineering (ESE) is a tool that enables some control of the initial geometry in heavy-ion collisions in a similar way as the centrality enables some control of the number of participants. Utilizing ESE, the path length in and out-of plane can be varied while keeping the medium properties (centrality) fixed. In this proceeding it is argued that this provides additional experimental information about jet quenching. Finally, it is suggested that if ESE studies are done in parallel for light and heavy quarks one can determine, in a model independent way, if the path-length dependence of their quenching differs.

  6. Investigating jet quenching on the lattice

    CERN Document Server

    Panero, Marco; Schäfer, Andreas

    2014-01-01

    Due to the dynamical, real-time, nature of the phenomenon, the study of jet quenching via lattice QCD simulations is not straightforward. In this contribution, however, we show how one can extract information about the momentum broadening of a hard parton moving in the quark-gluon plasma, from lattice calculations. After discussing the basic idea (originally proposed by Caron-Huot), we present a recent study, in which we estimated the jet quenching parameter non-perturbatively, from the lattice evaluation of a particular set of gauge-invariant operators.

  7. Fluorescence quenching of TMR by guanosine in oligonucleotides

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Nucleotide-specific fluorescence quenching in fluorescently labeled DNA has many applications in biotechnology. We have studied the inter-and intra-molecular quenching of tetramethylrhodamine (TMR) by nucleotides to better understand their quenching mechanism and influencing factors. In agreement with previous work, dGMP can effectively quench TMR, while the quenching of TMR by other nucleotides is negligible. The Stern-Volmer plot between TMR and dGMP delivers a bimolecular quenching constant of Ks=52.3 M-1. The fluorescence of TMR in labeled oligonucleotides decreases efficiently through photoinduced electron transfer by guanosine. The quenching rate constant between TMR and guanosine was measured using fluorescence correlation spectroscopy (FCS). In addition, our data show that the steric hindrance by bases around guanosine has significant effect on the G-quenching. The availability of these data should be useful in designing fluorescent oligonucleotides and understanding the G-quenching process.

  8. Preparation of briquettes on the basis of desintegrated phyto-materials and the admixture of fine-grained coal and coke

    Directory of Open Access Journals (Sweden)

    Jakabský Štefan

    2002-03-01

    Full Text Available The contribution deals with the preparation of small-diameter briquettes on the basis of desintegrated phyto-materials and the admixture of coal and coke. The phyto-materials are classified as a dry biomass that can be, on the one hand, the wastes from wood-working industry,(sawdust, chips, bark, etc. or dried mass from the plant production and, on the other hand, the mass of quick-growing plants cultivated on special plantations. In present time this renewable energy resource attracts attention by its heating value ranging from 10 to 16 MJ.kg-1 (EkoWATT, 2001, a low ash content of 0.5 – 6.5 % and by a low sulphur content in a water free sample of 0.05 –0.12 %.As a phyto-material the spruce sawdusts having a grain size of –2 mm were used. The admixture of brown coal, hard coal and coke with a grain size of 0.040 mm was added to the sawdust and in such way prepared mixtures were subjected to briquetting with the aim to obtain small-diameter briquettes. The influence of admixtures amount on the density, and the suitable briquetting press have been studied. A saleability of briquettes on the basis of phyto-materials is conditioned by their density that must be higher than 1,000 kg.m-3. Thus, an adding of denser material with a relatively high calorific value would enable to attain the required density as well as to retain and/or to improve the main utility properties, i.e. calorific value and ash content.The adding evinces itself in an enhancement of briquetting press, but also density of obtained briquettes is often much higher that required by the market. It was showed that in the case of clear spruce sawdust the density of 1,059 kg.m-3 under the briquetting press of 250 MPa can be attained. According to other results, an admixture of brown coal is not very favourable because briquetting press exceeds the value of 300 MPa. As to hard coal adding, the presses under 250 MPa were achieved at the content of 25 – 30 %. The density of these

  9. The analysis of thermal calculation for air stove drying system

    Directory of Open Access Journals (Sweden)

    Li Xue

    2012-08-01

    Full Text Available This article discusses the existing calculation of heat for a coal-fired hot-blast furnace. By utilizing the standard method of heat calculation for boilers, considering the relation between the theoretical combustion temperature and the excess air coefficient of the boiler, combining some operational parameters of a coal-fired powder hot-blast furnace, the heat calculation of iron ore concentrating dry combustion on a coal-fired hot stove is discussed. It is used to prevent coke and optimize combustion. It also discusses the advantages and disadvantages of flue gas recirculation systems. The conclusion will show the practical applications of this.

  10. Determination by mathematical modelling of the furnal theoretic optimum coke consumption as a function of the burden composition

    Energy Technology Data Exchange (ETDEWEB)

    Constantin, N.; Geanta, V.; Saban, R.; Bunea, D.

    1991-06-01

    The paper presents two statistical models for charges with 100% sinter and 100% ores, as parts of an overall model which shows the influence of the sinter and ore ratio in whole burdens (without coke) on the coke consumption. There are also presented equations and nomograms used for a quick determination of the coke and limestone specific consumption for any type of furnace burden. 7 refs., 3 figs.

  11. Application of Best Estimate Approach for Modelling of QUENCH-03 and QUENCH-06 Experiments

    Directory of Open Access Journals (Sweden)

    Tadas Kaliatka

    2016-04-01

    In this article, the QUENCH-03 and QUENCH-06 experiments are modelled using ASTEC and RELAP/SCDAPSIM codes. For the uncertainty and sensitivity analysis, SUSA3.5 and SUNSET tools were used. The article demonstrates that applying the best estimate approach, it is possible to develop basic QUENCH input deck and to develop the two sets of input parameters, covering maximal and minimal ranges of uncertainties. These allow simulating different (but with the same nature tests, receiving calculation results with the evaluated range of uncertainties.

  12. Validation of Quench Simulation and Simulation of the TWIN Solenoid

    CERN Document Server

    Pots, Rosalinde Hendrika

    2015-01-01

    For the Future Circular Collider at CERN a multi-purpose detector is proposed. The 6T TWIN Solenoid, a very large magnet system with a stored energy of 53 GJ, is being designed. It is important to protect the magnet against quenches in the system. Therefore several existing quench protection systems are evaluated and simulations have be performed on quenches in the TWIN Solenoid. The simulations on quenches in the TWIN Solenoid have been performed with promising results; the hotspot temperatures do not exceed 120 K and layer to layer voltages stay below 500 V. Adding quench heaters to the system might improve the quench protection system further.

  13. Analysis of superconducting cavity quench events at SSRF

    Institute of Scientific and Technical Information of China (English)

    HOU Hong-Tao; LI Zheng; LIU Jian-Fei; ZHAO Yu-Bin; ZHAO Shen-jie; ZHANG Zhi-Gang; LUO Chen; FENG Zi-Qiang; MAO Dong-Qing; ZHENG Xiang

    2011-01-01

    Quench is important and dangerous to superconducting RF cavities. This paper illustrates the mechanism of quench and how a quench detector works, and analyzes the quench events happening during beam operations and cavity conditioning. We find that the quench protection is mostly triggered by some reasons such as fluctuation of cavity voltage, multipacting or arc, rather than a real cavity thermal breakdown. The results will be beneficial to optimize the operation parameters of superconducting cavities, to discover the real reasons for beam trip by quench interlock, and to improve the operation stability of superconducting RF systems.

  14. Quenched heavy-light decay constants

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, R.M.; Booth, S.P.; Bowler, K.C.; Collins, S.; Henty, D.S.; Kenway, R.D.; Richards, D.G.; Shanahan, H.P.; Simone, J.N.; Simpson, A.D.; Wilkes, B.E. (Department of Physics, The University of Edinburgh, Edinburgh EH9 3JZ (United Kingdom)); Ewing, A.K.; Lellouch, L.; Sachrajda, C.T.; Wittig, H. (Physics Department, The University, Southampton SO9 5NH (United Kingdom)); (UKQCD Collaboration)

    1994-02-01

    We present results for heavy-light decay constants, using both propagating quarks and the static approximation, in [ital O]([ital a])-improved, quenched lattice QCD. At [beta]=6.2 on a 24[sup 3][times]48 lattice we find [ital f][sub [ital D

  15. LHC BFPP Quench Test with Ions (2015)

    CERN Document Server

    Schaumann, Michaela; Bahamonde Castro, Cristina; Auchmann, Bernhard; Chetvertkova, Vera; Giachino, Rossano; Jowett, John; Kalliokoski, Matti; Lechner, Anton; Mertens, Tom; Ponce, Laurette; CERN. Geneva. ATS Department

    2016-01-01

    The 2015 Pb-Pb collision run of the LHC operated at a beam energy of 6.37Z TeV. The power of the secondary beams emitted from the interaction point by the bound-free pair production (BFPP) process reached new levels while the propensity of the bending magnets to quench is higher at the new magnetic field levels. This beam power is about 70 times greater than that contained in the luminosity debris and is focussed on a specific location. As long foreseen, orbit bumps were introduced in the dispersion suppressors around the highest luminosity experiments to mitigate the risk of quenches by displacing and spreading out these losses. Because the impact position and intensity of these secondary beams is well known and can be tracked easily with the Beam Loss Monitors (BLMs), the BFPP1 beam (208Pb81+ ions), which is the most intense, provides a tool to accurately measure the steady state quench limit of the LHC main dipoles. At the moment the exact quench limit is not known, but this knowledge is important to asses...

  16. Lattice QCD simulations beyond the quenched approximation

    Energy Technology Data Exchange (ETDEWEB)

    Ukawa, A. (European Organization for Nuclear Research, Geneva (Switzerland). Theory Div.)

    1989-07-01

    Present status of lattice QCD simulations incorporating the effects of dynamical quarks is presented. After a brief review of the formalism of lattice QCD, the dynamical fermion algorithms in use today are described. Recent attempts at the hadron mass calculation are discussed in relation to the quenched results, and current understanding on the finite temperature behavior of QCD is summarized. (orig.).

  17. Characterization of tuyere-level core-drill coke samples from blast furnace operation

    Energy Technology Data Exchange (ETDEWEB)

    S. Dong; N. Paterson; S.G. Kazarian; D.R. Dugwell; R. Kandiyoti [Imperial College London, London (United Kingdom). Department of Chemical Engineering

    2007-12-15

    A suite of tuyere-level coke samples have been withdrawn from a working blast furnace during coal injection, using the core-drilling technique. The samples have been characterized by size exclusion chromatography (SEC), Fourier transform Raman spectroscopy (FT-RS), and X-ray powder diffraction (XRD) spectroscopy. The 1-methyl-2-pyrrolidinone (NMP) extracts of the cokes sampled from the 'bosh', the rear of the 'bird's nest', and the 'dead man' zones were found by SEC to contain heavy soot-like materials (ca. 10{sup 7}-10{sup 8} apparent mass units). In contrast, NMP extracts of cokes taken from the raceway and the front of the 'bird's nest' only contained a small amount of material of relatively lower apparent molecular mass (up to ca. 10{sup 5} u). Since the feed coke contained no materials extractable by the present method, the soot-like materials are thought to have formed during the reactions of volatile matter released from the injectant coal, probably via dehydrogenation and repolymerization of the tars. The Raman spectra of the NMP-extracted core-drilled coke samples showed variations reflecting their temperature histories. Area ratios of D-band to G-band decreased as the exposure temperature increased, while intensity ratios of D to G band and those of 2D to G bands increased with temperature. The graphitic (G), defect (D), and random (R) fractions of the carbon structure of the cokes were also derived from the Raman spectra. The R fractions decreased with increasing temperature, whereas G fractions increased, while the D fractions showed a more complex variation with temperature. These data appear to give clues regarding the graphitization mechanism of tuyere-level cokes in the blast furnace. 41 refs., 9 figs., 6 tabs.

  18. The effect of recycled plastics and cooking oil on coke quality.

    Science.gov (United States)

    Lange, Liséte Celina; Ferreira, Alison Frederico Medeiros

    2017-03-01

    This study assessed the effects of adding plastics and waste vegetable oil on the quality of coke in the coking process, on a pilot scale. A typical composition of the main plastics found in municipal solid waste was prepared using 33% HDPE, 5% LDPE, 10% PP, 21% PET, 24.8% PS, 5.2% PVC, 1% cellulose and also a 0.5% waste vegetable oil was added. The wastes were added to the coal blends in the proportions of 1%, 2% and 3% for plastics and 0.5% for vegetable oil. Two types of experiments were performed. The first was carried out in a hearth heating furnace (HHF) at temperatures of up to 900°C for a 7 h period. The second was a box test, which consists of heating coal blends in 18L cans using a pilot coking oven, for approximately 20 h at temperatures between 1050 and 1100°C. The quality parameters used for the assessment were the CSR (coke strength after reaction), CRI (coke reactivity index), ash, volatile matter and sulfur in order to identify the effect of plastic and vegetable oil on coke quality. Results for CSR in the HHF averaged 52.3%, and 56.63% in box test trials. The CRI results ranged from 26.6% to 35.7%. Among the different percentages of plastics used, 3% plastic blends provided the most stable CSR results. The industrial furnaces work at temperatures between 1100 and 1350°C and time coking 21-24h, compared to the test conditions achieved in the HHF and pilot furnace with box test. It was concluded that the results of CSR and CRI are consistent with the tests confirming the feasibility of using plastic in the steelmaking process. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Reduction behavior of hematite in the presence of coke

    Institute of Scientific and Technical Information of China (English)

    Ze-hong Wang; Guo-feng Li; Yong-sheng Sun; and Ming-zhao He

    2016-01-01

    The reduction kinetics of hematite in the presence of coke as a reductant was studied via isothermal and non-isothermal thermo-dynamic analyses. The isothermal reduction of hematite was conducted at a pre-determined temperature ranging from 1423 to 1573 K. The results indicated that a higher reduction temperature led to an increased reduction degree and an increased reduction rate. The non-isothermal reduction of hematite was carried out from room temperature to 1573 K at various heating rates from 5 to 15 K·min−1. A greater heating rate gave a greater reduction rate but decreased reduction degree. With an increase in temperature, both the reduction rate and the reduction de-gree increased at a smaller rate when the temperature was less than 1150 K, and they increased at a higher rate when the temperature was greater than 1150 K before completion of the reduction reaction. Both the isothermal and the non-isothermal reduction behaviors of hematite were described by the Avrami–Erofeev model. For the isothermal reduction, the apparent activation energy and pre-exponential factor were 171.25 kJ·mol−1 and 1.80 × 105 min−1, respectively. In the case of non-isothermal reduction, however, the apparent activation energy and pre-exponential factor were correlated with the heating rate.

  20. Experimental study on preheated combustion of pulverized semi-coke

    Science.gov (United States)

    Yao, Yao; Zhu, Jianguo; Lu, Qinggang; Zhou, Zuxu

    2015-06-01

    In a test rig, pulverized semi-coke was preheated to 850oC in a circulating fluidized bed (CFB) and then combusted at 1100oC in a down-fired combustor (DFC). Experiments were conducted to reveal the effects of three secondary air nozzle cases (co-axial jet, top circular jet and wall circular jet) on the NO emission. The results show that the optimized secondary air nozzle can reduce NO emission. O2 concentration profile is the major factor affecting NO generation and emission, which is led by the secondary air nozzle. The lower O2 concentration led to the generation of lower initial NO. The NO emission at the exit of the DFC was reduced from 189 to 92 mg/m3 (@ 6% O2) with the decrease of initial generation. The peak of NO at 100 mm below the nozzle should be attributed to the oxidization of NH3 in the syngas, rather than the oxidization of fuel-N in the char. The low and well-distributed O2 concentration contributes to the reduction of initial NO, which helps to reduce the NO emission. The combustion efficiencies of the cases of the co-axial jet, the top circular jet, and the wall circular jet are 97.88%, 98.94% and 98.74%, respectively.

  1. Kinetic model on coke oven gas with steam reforming

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jia-yuan; ZHOU Jie-min; YAN Hong-jie

    2008-01-01

    The effects of factors such as the molar ratio of H2O to CH4 (n(H2O)/n(CH4)), methane conversion temperature and time on methane conversion rate were investigated to build kinetic model for reforming of coke-oven gas with steam. The results of experiments show that the optimal conditions for methane conversion are that the molar ratio of H2O to CH4 varies from 1.1 to 1.3and the conversion temperature varies from 1 223 to 1 273 K. The methane conversion rate is more than 95% when the molar ratio ofH2O to CH4 is 1.2, the conversion temperature is above 1 223 K and the conversion time is longer than 0.75 s. Kinetic model of methane conversion was proposed. All results demonstrate that the calculated values by the kinetic model accord with the experimental data well, and the error is less than 1.5%.

  2. Simulation of the Quench-06 experiment with Scdapsim; Simulacion del experimento Quench-06 con Scdapsim

    Energy Technology Data Exchange (ETDEWEB)

    Angel M, E. del; Nunez C, A.; Amador G, R. [CNSNS, Dr. Barragan No. 779, 03020 Mexico D.F. (Mexico)]. e-mail: edangelm@cnsns.gob.mx

    2003-07-01

    The present work describes the pattern of the called Quench installation developed and used by the National Commission of Nuclear Security and Safeguards (CNSNS) for their participation in the International Standard Problem 45 (ISP), organized by the Nuclear Energy Agency (NEA). The exercise consisted on the simulation of the denominated experiment Quench-06 carried out in the experimental installation Quench located in the Forschungszentrum laboratory in Karlsruhe, Germany. The experiment Quench-06 consisted on simulating the sudden and late injection of water in a fuel assemble for a pressurized reactor (PWR). The CNSNS uses the version bd of the SCDAPSIM code developed by the company Innovative Software Systems (ISS) to simulate this experiment. The obtained results showed that the code is able to predict the experiment partially when overestimating the hydrogen production and of the partial fused of some fuel pellets, but predicting correctly the damage in the shroud. (Author)

  3. Simulation of bundle test Quench-12 with integral code MELCOR

    Energy Technology Data Exchange (ETDEWEB)

    Duspiva, J. [Nuclear Research Inst., Rez plc (Czech Republic)

    2011-07-01

    The past NRI analyses cover the Quench-01, Quench-03 and Quench-06 with version MELCOR 1.8.5 (including reflood model), and Quench-01 and Quench-11 tests with the latest version MELCOR 1.8.6. The Quench-12 test is specific, because it has different bundle configuration related to the VVER bundle configuration with hexagonal grid of pins and also used E110 cladding material. Specificity of Quench-12 test is also in the used material of fuel rod cladding - E110. The test specificities are a reason for the highest concern, because the VVER reactors are operated in the Czech Republic. The new input model was developed with the taking into account all experience from previous simulations of the Quench bundle tests. The recent version MELCOR 1.8.6 YU{sub 2}911 was used for the simulation with slightly modified ELHEAT package. Sensitivity studies on input parameters and oxidation kinetics were performed. (author)

  4. Analysis of quench in the NHMFL REBCO prototype coils for the 32 T Magnet Project

    Science.gov (United States)

    Breschi, M.; Cavallucci, L.; Ribani, P. L.; Gavrilin, A. V.; Weijers, H. W.

    2016-05-01

    A 32 T all-superconductive magnet with high field REBCO inner coils is under development at the National High Magnetic Field Laboratory, Tallahassee, Florida, USA. As part of the development activity, two prototype coils with full scale radial dimensions and final design features, but with reduced axial length were constructed. The prototype coils consist of six dry-wound double pancakes modules with uninsulated conductor and insulated stainless steel cowind. Quench studies on one of the prototype coils at 4.2 K in self-field and in a background magnetic field of 15 T were performed by activating a set of quench protection heaters. In this paper, we present a numerical analysis of the experimental results of the quench tests of one of the prototype coils. The numerical analysis was carried out through a coupled electro-thermal FEM model developed at the University of Bologna. The model is based on the coupling with distributed contact resistances of the coil pancakes described as 2D elements. A homogenization procedure of the REBCO tape and other coil materials is presented, which allows reducing the number of degrees of freedom and the computational effort. The model is applied to the analysis of the current and voltage evolutions during the experimental quench tests on the prototype coil.

  5. Compaction and Quenching of High-z Galaxies: Blue and Red Nuggets in Cosmological Simulations

    CERN Document Server

    Zolotov, Adi; Mandelker, Nir; Tweed, Dylan; Inoue, Shigeki; DeGraf, Colin; Ceverino, Daniel; Primack, Joel

    2014-01-01

    We use cosmological simulations to study a characteristic evolution pattern of high redshift galaxies. Early, stream-fed, highly perturbed, gas-rich discs undergo phases of dissipative contraction into compact, star-forming systems (blue nuggets) at z~4-2. The peak of gas compaction marks the onset of central gas depletion and inside-out quenching into compact ellipticals (red nuggets) by z~2. These are sometimes surrounded by gas rings or grow extended dry stellar envelopes. The compaction occurs at a roughly constant specific star-formation rate (SFR), and the quenching occurs at a constant stellar surface density within the inner kpc (Sigma_1). Massive galaxies quench earlier, faster, and at a higher Sigma_1 than lower-mass galaxies, which compactify and attempt to quench more than once. This evolution pattern is consistent with the way galaxies populate the SFR-radius-mass space, and with gradients and scatter across the main sequence. The compaction is triggered by an intense inflow episode, involving me...

  6. Single photon detection with self-quenching multiplication

    Science.gov (United States)

    Zheng, Xinyu (Inventor); Cunningham, Thomas J. (Inventor); Pain, Bedabrata (Inventor)

    2011-01-01

    A photoelectronic device and an avalanche self-quenching process for a photoelectronic device are described. The photoelectronic device comprises a nanoscale semiconductor multiplication region and a nanoscale doped semiconductor quenching structure including a depletion region and an undepletion region. The photoelectronic device can act as a single photon detector or a single carrier multiplier. The avalanche self-quenching process allows electrical field reduction in the multiplication region by movement of the multiplication carriers, thus quenching the avalanche.

  7. Comparison between UV and VUV photolysis for the pre- and post-treatment of coking wastewater.

    Science.gov (United States)

    Xing, Rui; Zheng, Zhongyuan; Wen, Donghui

    2015-03-01

    In this study, ultraviolet (UV) and vacuum ultraviolet (VUV) photolysis were investigated for the pre-treatment and post-treatment of coking wastewater. First, 6-fold diluted raw coking wastewater was irradiated by UV and VUV. It was found that 15.9%-35.4% total organic carbon (TOC) was removed after 24 hr irradiation. The irradiated effluent could be degraded by the acclimated activated sludge. Even though the VUV photolysis removed more chemical oxygen demand (COD) than UV, the UV-irradiated effluent demonstrated better biodegradability. After 4 hr UV irradiation, the biological oxygen demand BOD5/COD ratio of irradiated coking wastewater increased from 0.163 to 0.224, and its toxicity decreased to the greatest extent. Second, the biologically treated coking wastewater was irradiated by UV and VUV. Both of them were able to remove 37%-47% TOC within 8 hr irradiation. Compared to UV, VUV photolysis could significantly improve the transparency of the bio-treated effluent. VUV also reduced 7% more ammonia nitrogen (NH4+-N), 17% more nitrite nitrogen (NO2--N), and 18% more total nitrogen (TN) than UV, producing 35% less nitrite nitrogen (NO3--N) as a result. In conclusion, UV irradiation was better in improving the biodegradability of coking wastewater, while VUV was more effective at photolyzing the residual organic compounds and inorganic N-species in the bio-treated effluent.

  8. Sperm quality and DNA integrity of coke oven workers exposed to polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Jeng, Hueiwang Anna; Pan, Chih-Hong; Chao, Mu-Rong; Chiu, Chien-Chih; Zhou, Guodong; Chou, Chon-Kit; Lin, Wen-Yi

    2016-11-18

    The objective of this study was to assess sperm quality and deoxyribonucleic acid (DNA) integrity of coke oven workers exposed to polycyclic aromatic hydrocarbons (PAHs) as compared to control subjects. The coke oven workers (N = 52) and administrative staff (N = 35) of a steel plant served as the exposed and control groups, respectively. Exposure to PAHs was assessed by measuring 1-hydroxypyren. Analysis of sperm quality (concentration, motility, vitality, and morphology) was performed simultaneously with sperm DNA integrity analysis, including DNA fragmentation, denaturation, bulky DNA adducts, and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dGuo). A questionnaire was conducted to collect demographic and potential confounding data. The coke oven workers had lower percentages of sperm motility, vitality and normal morphology than the control group, but the difference was not significant. For DNA integrity, the coke oven workers had significantly higher concentrations of bulky DNA adducts and 8-oxo-dGuo than the control subjects (p = 0.009 and p = 0.048, respectively). However, DNA fragmentation percentages did not significantly increase as compared to those in the subjects from the control group (p = 0.232). There was no correlation between sperm quality parameters and DNA integrity indicators. Occupational exposure of the coke oven workers to PAHs was associated with decreased sperm DNA integrity. Int J Occup Med Environ Health 2016;29(6):915-926.

  9. Effective adsorption of phenolic compound from aqueous solutions on activated semi coke

    Science.gov (United States)

    Gao, Xiaoming; Dai, Yuan; Zhang, Yu; Fu, Feng

    2017-03-01

    Activated Semi coke was prepared by KOH activation and employed as adsorbent to study adsorption function of phenolic compound from aqueous solutions. The adsorption result showed that the adsorption capacity of the activated semi coke for phenolic compound increased with contact time and adsorbent dosage, and slightly affected by temperature. The surface structure property of the activated semi coke was characterized by N2 adsorption, indicating that the activated semi coke was essentially macroporous, and the BET surface area was 347.39 m2 g-1. Scanning electron microscopy indicated that the surface of the activated semi coke had a high developed pore. The adsorption kinetics were investigated according to pseudofirst order, pseudosecond order and intraparticle diffusion, and the kinetics data were fitted by pseudosecond order model, and intraparticle diffusion was not the only rate-controlling step. Adsorption isotherm was studied by Langmuir, Freundlich, Temkin, Redlich-Peterson, Sips and Toth models. The result indicated that adsorption isotherm data could fit well with Langmuir, Redlich-Peterson, Sips and Toth models.

  10. Colour change of soft denture liners after storage in coffee and coke.

    Science.gov (United States)

    Goiato, Marcelo Coelho; Zuccolotti, Bruna Carolina Rossatti; Moreno, Amália; dos Santos, Daniela Micheline; Pesqueira, Aldiéris Alves; Dekon, Stefan Fiuza de Carvalho

    2011-06-01

    This study was to evaluate the colour change of soft denture liners after thermocycling and storage in coffee and coke. Four liners, two silicone-based (Sofreliner S and Reline GS) and two acrylic resin-based (Soft Confort and Dentuflex), were evaluated in this study. Ten samples were obtained for each group. After 2000 cycles of thermocycling with baths of 5°C and 55°C, five samples were stored in coffee and the remaining samples in coke. The colour alteration was evaluated in a reflection spectrophotometer before and after thermocycling, and after 1, 3, 24, 48 and 96h of storage in coffee and coke. Data were submitted to anova and Tukey's HSD test (α=0.05). Thermocycling and storage period represented a higher statistically significant influence for the resin liners than for the silicone materials. Coke did not influence the colour stability of the materials during storage. However, the coffee solution generated statistically significant colour alteration in the material Soft Confort. In the comparison between the coffee and coke solutions, there was no statistically significant difference for colour alteration only for the material Dentuflex. The silicone liners presented better colour stability following thermocycling and storage independent of the solution. The coffee solution was a statistically significant factor for colour alteration of the material Soft Confort.

  11. Sperm quality and DNA integrity of coke oven workers exposed to polycyclic aromatic hydrocarbons

    Directory of Open Access Journals (Sweden)

    Hueiwang Anna Jeng

    2016-12-01

    Full Text Available Objectives: The objective of this study was to assess sperm quality and deoxyribonucleic acid (DNA integrity of coke oven workers exposed to polycyclic aromatic hydrocarbons (PAHs as compared to control subjects. Material and methods: The coke oven workers (N = 52 and administrative staff (N = 35 of a steel plant served as the exposed and control groups, respectively. Exposure to PAHs was assessed by measuring 1-hydroxypyren. Analysis of sperm quality (concentration, motility, vitality, and morphology was performed simultaneously with sperm DNA integrity analysis, including DNA fragmentation, denaturation, bulky DNA adducts, and 8-oxo-7,8-dihydro-2’-deoxyguanosine (8-oxo-dGuo. A questionnaire was conducted to collect demographic and potential confounding data. Results: The coke oven workers had lower percentages of sperm motility, vitality and normal morphology than the control group, but the difference was not significant. For DNA integrity, the coke oven workers had significantly higher concentrations of bulky DNA adducts and 8-oxo-dGuo than the control subjects (p = 0.009 and p = 0.048, respectively. However, DNA fragmentation percentages did not significantly increase as compared to those in the subjects from the control group (p = 0.232. There was no correlation between sperm quality parameters and DNA integrity indicators. Conclusions: Occupational exposure of the coke oven workers to PAHs was associated with decreased sperm DNA integrity. Int J Occup Med Environ Health 2016;29(6:915–926

  12. 40 CFR 1065.675 - CLD quench verification calculations.

    Science.gov (United States)

    2010-07-01

    ... verification calculations. Perform CLD quench-check calculations as follows: (a) Perform a CLD analyzer quench... water content in combustion air, fuel combustion products, and dilution air (if applicable). If you... the maximum expected CO2 content in fuel combustion products and dilution air. (d) Calculate quench...

  13. Static and dynamic quenching of luminescent species in polymer media.

    Science.gov (United States)

    Hartmann, P; Leiner, M J; Lippitsch, M E

    1994-12-01

    A method developed for quantitative determination of static and dynamic contributions to luminescence quenching is applied to Ru(II) complexes in polymer matrices (silica gel and polystyrene), quenched by oxygen. This method is based on both intensity and lifetime quenching experiments. The curvature of intensity Stern-Volmer plots is related to the results.

  14. First experience with the new coupling loss induced quench system

    NARCIS (Netherlands)

    Ravaioli, E.; Datskov, V.I.; Dudarev, A.V.; Kirby, G.; Sperin, K.A.; Kate, ten H.H.J.; Verweij, A.P.

    2014-01-01

    New-generation high-field superconducting magnets pose a challenge relating to the protection of the coil winding pack in the case of a quench. The high stored energy per unit volume calls for a very efficient quench detection and fast quench propagation in order to avoid damage due to overheating. A

  15. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Eye Symptoms Causes of Dry Eye Dry Eye Treatment What Is Dry Eye? Written By: Kierstan Boyd ... your vision. Privacy Policy Related New Dry Eye Treatment is a Tear-Jerker Jul 21, 2017 Three ...

  16. Collapse and Revival in Holographic Quenches

    CERN Document Server

    da Silva, Emilia; Mas, Javier; Serantes, Alexandre

    2014-01-01

    We study holographic models related to global quantum quenches in finite size systems. The holographic set up describes naturally a CFT, which we consider on a circle and a sphere. The enhanced symmetry of the conformal group on the circle motivates us to compare the evolution in both cases. Depending on the initial conditions, the dual geometry exhibits oscillations that we holographically interpret as revivals of the initial field theory state. On the sphere, this only happens when the energy density created by the quench is small compared to the system size. However on the circle considerably larger energy densities are compatible with revivals. Two different timescales emerge in this latter case. A collapse time, when the system appears to have dephased, and the revival time, when after rephasing the initial state is partially recovered. The ratio of these two times depends upon the initial conditions in a similar way to what is observed in some experimental setups exhibiting collapse and revivals.

  17. Quench from Mott Insulator to Superfluid

    Energy Technology Data Exchange (ETDEWEB)

    Zurek, Wojciech H. [Los Alamos National Laboratory; Dziarmaga, Jacek [Instytut Fizyki Uniwersytetu Jagiello´nskiego; Tylutki, Marek [Instytut Fizyki Uniwersytetu Jagiello´nskiego

    2012-06-01

    We study a linear ramp of the nearest-neighbor tunneling rate in the Bose-Hubbard model driving the system from the Mott insulator state into the superfluid phase. We employ the truncated Wigner approximation to simulate linear quenches of a uniform system in 1...3 dimensions, and in a harmonic trap in 3 dimensions. In all these setups the excitation energy decays like one over third root of the quench time. The -1/3 scaling is explained by an impulse-adiabatic approximation - a variant of the Kibble-Zurek mechanism - describing a crossover from non-adiabatic to adiabatic evolution when the system begins to keep pace with the increasing tunneling rate.

  18. Energy upgrade as regards quench performance

    Energy Technology Data Exchange (ETDEWEB)

    MacKay, W.W.; Tepikian, S.

    2011-01-01

    Since the cross section for W production increases rapidly with energy, we consider the possibility of increasing the collision energy of polarized protons at RHIC. The limits of present hardware are examined with a particular emphasis on the quench training performance of magnets. Ignoring the limits of the DX magnets, the short-sample currents for the main arc (8 cm) dipoles could allow an increase of more than 30%, however we estimate 400 to 500 training quenches for the just 8 cm dipoles to reach this level. We propose that a 10% increase in energy might be achieved with the present hardware configuration. Raising the beam energy to 275 GeV ({radical}s = 550 GeV) should increase the W production rate by almost 50% from the 250 GeV level for the same optics with identical {beta}*'s at the collision points.

  19. Quench dynamics in silver coated YBCO tapes

    Science.gov (United States)

    Duckworth, R. C.; Pfotenhauer, J. M.; Lue, J. W.; Gouge, M. J.; Lee, D. F.; Kroeger, D. M.

    2002-05-01

    The role of silver in the quench dynamics of RABiTS-processed YBCO tapes was examined. The voltage distribution along the 20 cm long YBCO tapes with silver thickness between two and eight micrometers was measured when different transport current pulses were applied. Measurements on each sample were performed in a conduction-cooling environment at approximately 50 K. After normal regions were induced in the sample by short over-current pulses, an operating current was applied to monitor the sample recovery or quench. When scaled to the lowest critical current, a thermal runaway current was identified and found to increase with increasing silver thickness. A simple one-dimensional model of the system supported this trend. [This paper is also published in Advances in Cryogenic Engineering Volume 47A, AIP Conference Proceedings Volume 613, pp. 449-456.

  20. Quench dynamics of the anisotropic Heisenberg model.

    Science.gov (United States)

    Liu, Wenshuo; Andrei, Natan

    2014-06-27

    We develop an analytical approach for the study of the quench dynamics of the anisotropic Heisenberg model (XXZ model) on the infinite line. We present the exact time-dependent wave functions after a quench in an integral form for any initial state and for any anisotropy Δ by means of a generalized Yudson contour representation. We calculate the evolution of several observables from two particular initial states: starting from a local Néel state we calculate the time evolution of the antiferromagnetic order parameter-staggered magnetization; starting from a state with consecutive flipped spins (1) we calculate the evolution of the local magnetization and express it in terms of the propagation of magnons and bound state excitations, and (2) we predict the evolution of the induced spin currents. These predictions can be confronted with experiments in ultracold gases in optical lattices. We also show how the "string" solutions of Bethe ansatz equations emerge naturally from the contour approach.

  1. Collapse and revival in holographic quenches

    Science.gov (United States)

    da Silva, Emilia; Lopez, Esperanza; Mas, Javier; Serantes, Alexandre

    2015-04-01

    We study holographic models related to global quantum quenches in finite size systems. The holographic set up describes naturally a CFT, which we consider on a circle and a sphere. The enhanced symmetry of the conformal group on the circle motivates us to compare the evolution in both cases. Depending on the initial conditions, the dual geometry exhibits oscillations that we holographically interpret as revivals of the initial field theory state. On the sphere, this only happens when the energy density created by the quench is small compared to the system size. However on the circle considerably larger energy densities are compatible with revivals. Two different timescales emerge in this latter case. A collapse time, when the system appears to have dephased, and the revival time, when after rephasing the initial state is partially recovered. The ratio of these two times depends upon the initial conditions in a similar way to what is observed in some experimental setups exhibiting collapse and revivals.

  2. Reductive fluorescence quenching of DMP with aniline

    Energy Technology Data Exchange (ETDEWEB)

    Asha Jhonsi, M. [B.S. Abdur Rahman University, Vandalur, Chennai 600048, Tamil Nadu (India); Kathiravan, A., E-mail: akathir23@hotmail.com [National Centre for Ultrafast Processes, University of Madras, Taramani Campus, Chennai 600113, Tamil Nadu (India)

    2014-01-15

    The photoinduced electron transfer (PET) between 8-(4-methoxyphenyl)-3,5-di[(E)-1-(4-methoxyphenyl)methylidene]-1,2,3,5,6, 7-hexahydrodicyclopenta[b,e]pyridine (DMP) and aniline is studied in acetonitrile medium by using steady state and time resolved absorption and fluorescence spectroscopic methods. Bimolecular quenching rate constants (k{sub q}) were calculated from the obtained linear Stern–Volmer plots from both steady state and time resolved measurements. The rate constant (k{sub q}) for PET between DMP and aniline is 1.4×10{sup 10} M{sup −1} s{sup −1}, which is in diffusion control limit. The free energy change (ΔG{sup 0}) has been evaluated by using Rehm–Weller equation for the evidence of electron transfer from aniline to DMP. Direct evidence for the electron transfer reaction in the present system has been obtained by characterizing the aniline cation radical using nanosecond time resolved absorption measurements in the visible region. Further, this quenching mechanism is attributed to be reductive in nature i.e. electron transfer occurs from ground state aniline to excited DMP. This is the first example of reductive fluorescence quenching of DMP with aniline in acetonitrile ever known. -- Highlights: • Photoinduced electron transfer between DMP and aniline using time resolved absorption and fluorescence spectroscopy has been investigated. • Reductive quenching behavior was observed. • Direct evidence for the ET reaction in the present system has been obtained by characterizing the aniline cation radical.

  3. Quenching of the Deuteron in Flight

    CERN Document Server

    Dillig, M

    2006-01-01

    We investigate the Lorentz contraction of a deuteron in flight. Our starting point is the Blankenbecler-Sugar projection of the Bethe-Salpeter equation to a 3-dimensional quasi potential equation, wqhich we apply for the deuteron bound in an harmonic oscillator potential (for an analytical result) and by the Bonn NN potential for a more realistic estimate. We find substantial quenching with increasing external momenta and a significant modification of the high momentum spectrum of the deuteron.

  4. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Español Eye Health / Eye Health A-Z Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms ... Dry Eye Dry Eye Treatment What Is Dry Eye? Written By: Kierstan Boyd Reviewed By: Brenda Pagan- ...

  5. What Is Dry Eye?

    Medline Plus

    Full Text Available ... Español Eye Health / Eye Health A-Z Dry Eye Sections What Is Dry Eye? Dry Eye Symptoms ... Dry Eye Dry Eye Treatment What Is Dry Eye? Leer en Español: ¿Qué Es el Ojo Seco? ...

  6. Measurements of volatile hydrocarbons in ambient air coking plant `Walbrzych`

    Energy Technology Data Exchange (ETDEWEB)

    Michalski, R.; Weglarz, A.; Skrok, R. [Polish Academy of Sciences, Zabrze (Poland). Inst. of Environmental Engineering

    1998-12-31

    The air is a matrix very difficult to handle. In addition, the pollutants are usually present at very low concentrations. Many techniques can be used to collect air samples. The simplest way is to use special containers, but this procedure is expensive and time-consuming. The adsorption of pollutants on adsorbents shows a growing interest, despite the difficulty to choose the appropriate support in order to obtain quantitative yields. To overcome this problem, two or three types of adsorbents may be used in series for collecting a wide range of analytes. In addition, the miniaturization of these techniques (i.e. microtraps and solid-phase microextraction) is also very promising: easy to handle, low cost, no solvent required, detection limits at ppt level when sensitive detectors are used. If we have no money for this modern equipment we must use traditional methods for compounds determination. This paper describes measurements of volatile hydrocarbons (such as benzene, toluene, ethylbenzene, xylene and phenol) in ambient air of coking plant `Walbrzych` Measuring points were at streets: Beethoven 4, Dworcowa 2, Kosteckiego 5 and Zamkowa 1. BTEX were collected on graphitized carbon and phenol on Chromosorb 102. After that samples were extracted by solvents (dichloromethane for BTEX or benzene for phenol). Next step was the analysis by gas chromatography with flame ionization detector without preconcentration. The lower limit of detection was circa 0.01 {mu}g/m{sup 3} for each of the determined compounds. These measurements of hydrocarbons in town of Walbrzych were performed for two years from 1996 to 1998. 2 tabs.

  7. Successful magnet quench test for CAST.

    CERN Multimedia

    Brice Maximilien

    2002-01-01

    The CERN Axion Solar Telescope (CAST) consists of a prototype LHC dipole magnet with photon detectors at each end. It searches for very weakly interacting neutral particles called axions, which should originate in the core of the Sun. The telescope, located at Point 8, can move vertically within its wheeled platform, which travels horizontally along tracks in the floor. In this way, the telescope can view the Sun at sunrise through one end and at sunset through the other end. It has been cooled down to below 1.8 K and reached ~95% of its final magnetic field of 9 tesla before a quench was induced to test the whole cryogenic system under such conditions. The cryogenic system responded as expected to the magnet quench and CAST is now ready to start its three-year search for solar axions. Photos 01 & 02 : Members of the LHC cryogenics team pose in front of the axion telescope on the day of the first quench test, together with some of the CAST collaboration.

  8. 41 CFR 101-26.4904-416 - DD Form 416: Purchase Request for Coal, Coke, or Briquettes.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true DD Form 416: Purchase Request for Coal, Coke, or Briquettes. 101-26.4904-416 Section 101-26.4904-416 Public Contracts and... DD Form 416: Purchase Request for Coal, Coke, or Briquettes. Note: The form illustrated in §...

  9. Peculiarities of accumulation of nonstructural carbohydrates in shoots of various species of acer genus in conditions of coke process

    Directory of Open Access Journals (Sweden)

    V. S. Bilchuk

    2005-11-01

    Full Text Available The research results on influence of the by-product-coking industry emission on starch and saccharose accumulation in sprouts of the Acer L. species are presented. The toxic ingredients of the coke production wastes inhibit the process of starch hydrolysis that provokes considerable decrease of the sugars content and negative influence on the plants’ winter hardiness are established.

  10. Pre-commissioning of 120 kt/a Unit for Hydrotreating Crude Coke Oven Benzene Implemented at Baoyuan Chemical Company

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ The Baoyuan Chemical Company, Ltd. in Taiyuan has per-formed the precommissioning of a 120 kt/a unit for hydrotreating crude coke oven benzene. This unit is the phase II construction of the 300 kt/a crude benzene hydrotreating project, which adopts the process technology for hydrotreating crude coke oven benzene developed indepen-dently by our own efforts.

  11. The Mass Dependence of Dwarf Satellite Galaxy Quenching

    Science.gov (United States)

    Slater, Colin T.; Bell, Eric F.

    2014-09-01

    We combine observations of the Local Group with data from the NASA-Sloan Atlas to show the variation in the quenched fraction of satellite galaxies from low-mass dwarf spheroidals and dwarf irregulars to more massive dwarfs similar to the Magellanic Clouds. While almost all of the low-mass (M sstarf 5 Gyr ago. We also characterize how the susceptibility of dwarfs to ram pressure must vary as a function of mass if it is to account for the change in quenched fractions. Though neither model predicts the quenching effectiveness a priori, this modeling illustrates the physical requirements that the observed quenched fractions place on possible quenching mechanisms.

  12. Model Predictive Control with Feedforward Strategy for Gas Collectors of Coke Ovens

    Institute of Scientific and Technical Information of China (English)

    Kai Li; Dewei Li; Yugeng Xi; Debin Yin

    2014-01-01

    In coking process, the production quality, equipment life, energy consumption, and process safety are all influenced by the pressure in gas collector pipe of coke oven, which is frequently influenced by disturbances. The main control objectives for the gas collector pressure system are keeping the pressures in collector pipes at appropriate operating point. In this paper, model predictive control (MPC) strategy is introduced to control the collector pressure system due to its ability to handle constraint and good control performance. Based on a method proposed to simplify the system model, an extended state space model predictive control is designed, which combines the feedforward strategy to eliminate the disturbance. The simulation results in a system with two coke ovens show the feasibility and effectiveness of the control scheme.

  13. Coke gasification with carbon dioxide. Gasificacion de un coque con dioxido de carbono

    Energy Technology Data Exchange (ETDEWEB)

    Pis, J.J.; Perez, A.J.; Fuertes, A.B.; Jul, J.J.; Lorenzana, J.J. (CSIC Instituto Nacional del Carbon, Oviedo (Spain))

    1988-01-01

    Variations in pore structure provide a very useful tool in the kinetics analysis of coal gasification. In this work gasification with CO[sub 2] of a coke has been carried out between 1041 and 1140 K at different burn-offs. The textural evolution of the produced materials has been studied. The coke has been produced from a bituminous coal, Consol M, by heating at 1273 K in an experimental furnace at 5 K/min. A simplified mathematical model was adopted to express the gasification of coke. Kinetic parameters were determined. The model fits experimental data very well. The apparent density decreases with the burn-off and porosity rises, linearly with gasification. 21 refs., 7 figs., 5 tabs.

  14. Effect and mechanism of coking residual ammonia water treating by flue gas

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The treatment of coking residual ammonia water has been a bigdifficult problem at home and abroad, and there is no breakthrough research achievement in the past. The invention patent "The method of treating all coking wastewater or treating coking residual ammonia water by flue gas" has been successfully used in Huaian Steel Works for high concentration and organic industry wastewater treatment. Not only can it realize the wastewater zero discharge, but also the wastewater treatment has an effect of de-sulfur and de-nitrogen for flue gas. So that the flue gas exhaustcan meet the requirement of emission standard. The mass transfer and heat transfer, fly ash absorption and coagulation, acid and alkali neutralization reaction, catalysis oxidation and reduction reaction in flue gas would be the major factors.

  15. Modified sequential extraction for biochar and petroleum coke: Metal release potential and its environmental implications.

    Science.gov (United States)

    von Gunten, Konstantin; Alam, Md Samrat; Hubmann, Magdalena; Ok, Yong Sik; Konhauser, Kurt O; Alessi, Daniel S

    2017-07-01

    A modified Community Bureau of Reference (CBR) sequential extraction method was tested to assess the composition of untreated pyrogenic carbon (biochar) and oil sands petroleum coke. Wood biochar samples were found to contain lower concentrations of metals, but had higher fractions of easily mobilized alkaline earth and transition metals. Sewage sludge biochar was determined to be less recalcitrant and had higher total metal concentrations, with most of the metals found in the more resilient extraction fractions (oxidizable, residual). Petroleum coke was the most stable material, with a similar metal distribution pattern as the sewage sludge biochar. The applied sequential extraction method represents a suitable technique to recover metals from these materials, and is a valuable tool in understanding the metal retaining and leaching capability of various biochar types and carbonaceous petroleum coke samples. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Occupational exposure to aromatic hydrocarbons and polycyclic aromatic hydrocarbons at a coke plant.

    Science.gov (United States)

    Bieniek, Grażyna; Łusiak, Agnieszka

    2012-08-01

    The objective of this study was to assess the external exposure to aromatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs) of coke-oven workers and by-product workers at a coke plant in Poland. The content of benzene, toluene, xylene, and naphthalene in a gaseous phase and the content of dibenzo[a,h]anthracene, benz[a]anthracene, anthracene, benzo[a]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benz[ghi]perylene, chrysene, and indeno[1,2,3-c,d]pyrene in a particulate phase of coke plant workers were measured in the workers mentioned above. A toxic equivalency factor BaP(eq) was used to estimate human health risk associated with respiratory exposure to PAHs. Time-weighted values of the exposure to AHs in the coke plant were as follows: benzene (range 0.01-2.71 mg m(-3)), toluene (0.01-1.73 mg m(-3)), xylene (0.01-0.78 mg m(-3)), naphthalene (6.0-6079 μg m(-3)), and the concentrations of hydrocarbons did not exceed the exposure limits. The results for particle-bound PAHs were equal to 1.96 μg m(-3) for B(a)P, 0.73 μg m(-3) for DBA, 3.23 μg m(-3) for BaA, 4.35 μg m(-3) for BbF, 3.02 μg m(-3) for BkF, 4.54 μg m(-3) for IND, 4.32 μg m(-3) for CHR, and 0.73 μg m(-3) for Ant. The results of personal air measurements (median values of the sum of nine carcinogenic PAHs) were 2.115 μg m(-3) (coke-oven workers, n = 207), 0.326 μg m(-3) (coke by-product workers, n = 33), and 0.653 μg m(-3) (total area workers, n = 38). The benzo[a]pyrene equivalent concentrations (BaP(eq)) of 10 PAHs were 1.33, 0.183, and 0.284 μg m(-3), respectively. We found out that coke plant workers are simultaneously exposed to a mixture of aromatic and polycyclic hydrocarbons present in the breathing zone air. Exposure levels are significantly influenced by job categories. Coke by-product workers are significantly more exposed to benzene, toluene, and xylene and less to PAHs. Coke-oven workers are mainly exposed to PAHs. Coke-oven workplaces (top side, coke side, and

  17. The year-book of the Coke Oven Managers' Association 2007

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    The 88th volume of the Year Book outlines activities of the Coke Oven Managers' Association throughout 2007 and reproduces transactions presented to the industry through its various sections. It includes lists of Council and committee members and representation on committees and past presidents, and a full list of members. Reports of Council 2005-6 and of the annual general meeting 2005 are included. The Presidential address by R.G.W. Sargent looks at the situation faced by coke oven managers through the decades with some predictions for the future. Carbonisation and briquetting works in the United Kingdom, Koppers carbon materials and chemical works in the UK and Europe, European coking plants, their addresses and managers are listed. Nine transactions are abstracted separately on the Coal Abstracts database.

  18. The year-book of the Coke Oven Managers' Association 2008

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    The 89th volume of the Year Book outlines activities of the Coke Oven Managers' Association throughout 2008 and reproduces transactions presented to the industry through its various sections. It includes lists of Council and Committee members and representation on committees and past presidents, and a full list of members. Reports of Council 2006-7 and of the annual general meeting 2007 are included. The Presidential address by A. Moore is about his experiences at Redcar Coke Ovens. Carbonisation and briquetting works in the United Kingdom, Koppers carbon materials and chemical works in the UK and Europe, European coking plants, their addresses and managers are listed. Six transactions are abstracted separately on the Coal Abstracts database.

  19. Thermodynamic analysis for a regenerative gas turbine cycle in coking process

    Directory of Open Access Journals (Sweden)

    Zelong Zhang, Lingen Chen, Yanlin Ge, Fengrui Sun

    2014-01-01

    Full Text Available A regenerative gas turbine cycle driven by residual coke oven gas is proposed in this paper. The thermal efficiency and the work output (per ton of coke of the system are analyzed based on thermodynamics and the theory of gas turbine cycle. The influences of the gas release rate, the residual gas rate and the effectiveness of regenerator on the performance of the cycle are analyzed by using numerical examples. It is found that the work output increases with the increase of the residual gas rate while decreases with the increase of the gas release rate. The cycle with regenerator can reach higher thermal efficiency and bigger work output, which means that the coke oven gas is used more effectively. Moreover, there exist two optimal pressure ratios of compressor which lead the maximum thermal efficiency and the maximum specific work, respectively.

  20. Application of best estimate approach for modelling of QUENCH-03 and QUENCH-06 experiments

    Energy Technology Data Exchange (ETDEWEB)

    Kaliatka, Tadas; Kaliatka, Algirdas; Vileiniskis, Virginijus [Laboratory of Nuclear Installation Safety, Lithuanian Energy Institute, Breslaujos (Lithuania)

    2016-04-15

    One of the important severe accident management measures in the Light Water Reactors is water injection to the reactor core. The related phenomena are investigated by performing experiments and computer simulations. One of the most widely known is the QUENCH test-program. A number of analyses on QUENCH tests have also been performed by different computer codes for code validation and improvements. Unfortunately, any deterministic computer simulation is not free from the uncertainties. To receive the realistic calculation results, the best estimate computer codes should be used for the calculation with combination of uncertainty and sensitivity analysis of calculation results. In this article, the QUENCH-03 and QUENCH-06 experiments are modelled using ASTEC and RELAP/SCDAPSIM codes. For the uncertainty and sensitivity analysis, SUSA3.5 and SUNSET tools were used. The article demonstrates that applying the best estimate approach, it is possible to develop basic QUENCH input deck and to develop the two sets of input parameters, covering maximal and minimal ranges of uncertainties. These allow simulating different (but with the same nature) tests, receiving calculation results with the evaluated range of uncertainties.

  1. Electrochemical characteristics of lithium intercalation into natural gas coke serving as the negative electrode of a lithium battery

    Energy Technology Data Exchange (ETDEWEB)

    Pan Qinmin; Deng Zhenghua; Zhang Xiaozheng; Wan Guoxiang (Chinese Academy of Sciences, Chengdu (China). Chengdu Inst. of Organic Chemistry)

    1999-05-01

    The electrochemical characteristics of a new type of coke for the negative electrode of a lithium ion battery are investigated. This coke is prepared from natural gas by means of thermoplasma technology. The initial discharge-charge properties of natural gas coke of several kinds are discussed. The effects of surface modification of cokes on the characteristics of lithium intercalation during the first cycle are also explored. The properties of lithium intercalation into carbon electrodes show that the electrochemical behaviour is determined by the nature of the carbon material. The results also demonstrate that the surface properties of carbon electrodes remarkably influence the efficiency of the first cycle. Surface modification of coke electrodes with polymer can increase the initial coulombic efficiency but reduces the initial discharge capacity. (orig.)

  2. Quench propagation and protection analysis of the ATLAS Toroids

    CERN Document Server

    Dudarev, A; ten Kate, H H J; Baynham, D Elwyn; Courthold, M J D; Lesmond, C

    2000-01-01

    The ATLAS superconducting magnet system consists of the Barrel Toroid, two End Cap Toroids and the Central Solenoid. However, the Toroids of eight coils each are magnetically separate systems to the Central Solenoid. The Toroids are electrically connected in series and energized by a single power supply. The quench protection system is based on the use of relatively small external dump resistances in combination with quench-heaters activated after a quench event detection to initiate the internal dump of stored energy in all the coils. A rather strong quench-back effect due to eddy-currents in the coil casings at the transport current decay is beneficial for the quench protection efficiency in the event of heater failures. The quench behaviour of the ATLAS Toroids was computer simulated for normal operation of the quench protection system and its complete non-operation (failure) mode. (3 refs).

  3. Comparison of quenching and extraction methodologies for metabolome analysis of Lactobacillus plantarum

    Directory of Open Access Journals (Sweden)

    Faijes Magda

    2007-08-01

    Full Text Available Abstract Background A reliable quenching and metabolite extraction method has been developed for Lactobacillus plantarum. The energy charge value was used as a critical indicator for fixation of metabolism. Results Four different aqueous quenching solutions, all containing 60% of methanol, were compared for their efficiency. Only the solutions containing either 70 mM HEPES or 0.85% (w/v ammonium carbonate (pH 5.5 caused less than 10% cell leakage and the energy charge of the quenched cells was high, indicating rapid inactivation of the metabolism. The efficiency of extraction of intracellular metabolites from cell cultures depends on the extraction methods, and is expected to vary between micro-organisms. For L. plantarum, we have compared five different extraction methodologies based on (i cold methanol, (ii perchloric acid, (iii boiling ethanol, (iv chloroform/methanol (1:1 and (v chloroform/water (1:1. Quantification of representative intracellular metabolites showed that the best extraction efficiencies were achieved with cold methanol, boiling ethanol and perchloric acid. Conclusion The ammonium carbonate solution was selected as the most suitable quenching buffer for metabolomics studies in L. plantarum because (i leakage is minimal, (ii the energy charge indicates good fixation of metabolism, and (iii all components are easily removed during freeze-drying. A modified procedure based on cold methanol extraction combined good extractability with mild extraction conditions and high enzymatic inactivation. These features make the combination of these quenching and extraction protocols very suitable for metabolomics studies with L. plantarum.

  4. 焦炉热工测试分析%Thermal test analysis of coke oven

    Institute of Scientific and Technical Information of China (English)

    李强生; 王丽丽; 赵春竹; 丛伟; 谢国威

    2014-01-01

    通过对焦炉的热工测试分析,定量反应了焦炉炉况,并对焦炉各项指标进行了评定,为进一步采取措施提升焦炉热效率,实现低能高效生产具有指导意义。%The thermal test analysis reflected the energy characteristic of coke oven in quantify .It e-valuated the indicators of coke oven , had a guiding significance to increase thermal efficiency by tak-ing further measures and realize efficient production by low energy consumption .

  5. Systems for the coke dedusting and oven pushing; Sistema de despoeiramento do desenfornamento de coque

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Vander L. da; Silvares, Paulo T.B.; Tardin, Jose G.C.; Nemtzoff, Vladimir; Vasconcelos, Celso P. de; Morimoto, Tsutomu; Diesel, Adilson [Companhia Siderurgica de Tubarao, ES (Brazil)

    1989-12-31

    With the evolution of the siderurgy industrial set-ups, it became necessary to protect the environment and the environment control turned into a factor of great influence in the viability and expansion of existing plants or new projects. In the coke oven plants a great pollution source is related to the oven pushing.In order to reduce the environmental impact related to this procedure, C.S.T. implemented a dedusting system in the coke guide, remarkably improving the working conditions. 3 refs., 3 figs., 4 tabs.

  6. Effet des proprietes du coke sur les proprietes d'anodes

    Science.gov (United States)

    Sarkar, Arunima

    One of the major components of the primary aluminum fabrication process is carbon anode manufacturing. High density, low electrical resistivity, and consistence of the quality of anodes are of utmost interest in aluminum industry. This work was undertaken to determine the desired coke properties which have notable impact on coke/pitch wetting and the influence of some of these properties on anode quality, and finally to identify the factors effecting the consumption of industrial anodes throughout the entire process. (Abstract shortened by ProQuest.).

  7. Decomposition of Organic Compounds in Coke Plant Wastewater by Ultrasonic Irradiation and Its Combined Process

    Institute of Scientific and Technical Information of China (English)

    XU Jin-qiu; JIA Jin-ping; WANG Jing-wei

    2004-01-01

    The paper deals with the degradation of the organic compounds in the coke plant wastewater by the combined process of ultrasonic irradiation and activated sludge. The influence factors of the ultrasonic degradation effect such as air atmosphere, initial concentration, ultrasonic power density and the category and consumption of catalyst were investigated. A water quality model was used to explain the degradation of different kinds of organic compounds in the coke plant wastewater by ultrasonic irradiation. After the wastewater was treated by the combined process of ultrasonic irradiation and activated sludge, the COD degradation efficiency was 95. 74 %, which is 63. 49% higher than that by the process of activated sludge alone.

  8. Construction solutions applied at coke oven battery no. 7 in the aspect of international requirements

    Energy Technology Data Exchange (ETDEWEB)

    Tadeusz Maj; Mariola Honisz; Wladyslaw Latocha; Wiktor Humer; Ludwik Kosyrczyk [' Zdzieszowice' Coking Plant Ltd. (Poland)

    2004-07-01

    15 slides/overheads outline this presentation. In February 2003 a new coke oven battery was put into operation in Zdzieszowice. In view of Poland's joining the European Union a series of technical solutions were implemented to improve working conditions in addition to improving the technology of the coking process. The paper describes the actions taken over one and a half years of operation. These include maintaining the recommended low level of NOx emission (comparable to that of CO) by waste gas recirculation.

  9. Effects of mechanical activation on the carbothermal reduction of chromite with metallurgical coke

    Directory of Open Access Journals (Sweden)

    Kenan Yıldız

    2010-06-01

    Full Text Available The carbothermal reduction of mechanically activated chromite with metallurgical coke under an argon atmosphere was investigated at temperatures between 1100 and 1400°C and the effects of the mechanical activation on chromite structure were analyzed by x-ray diffraction (XRD and scanning electron microscopy (SEM. An increase in specific surface area resulted in more contact points. The activation procedure led to amorphization and structural disordering in chromite and accelerated the degree of reduction and metalization in the mixture of chromite and metallurgical coke. Carbothermal reduction products were analzed by using scanning electron microscopy (SEM/EDS.

  10. The treatment of a deposited lignite pyrolysis wastewater by adsorption using activated carbon and activated coke

    Energy Technology Data Exchange (ETDEWEB)

    Wiessner, A.; Remmler, M.; Kuschk, P.; Stottmeister, U. [UFZ-Umweltforschungszentrum Leipzig-Halle GmbH, Leipzig (Germany). Dept. of Remediation Research

    1998-07-31

    This paper investigated activated carbon and activated coke adsorption for the treatment of highly contaminated discoloured industrial wastewater with a wide molecular size distribution of organic compounds. Lignite pyrolysis wastewater from a filled open-cast coal mine was used for continuous and discontinuous experiments. The investigations were performed using water samples taken from various depths of the deposits ponds. A comparison of the capacities of the adsorption materials used showed, that because of its large number of macro and mesopores, activated coke is more suitable for wastewater treatment and in addition cheaper than activated carbon.

  11. Characterization of Metallurgical Coke Produced with Coal Mixtures and Waste Tires

    OpenAIRE

    Silva,Guilherme Liziero Ruggio da; Silva,Renata Dias; Cheloni,Leticia; Moreira,Victor Eric de Souza; Haneiko,Natália Brasil Dias; Assis, Paulo Santos

    2016-01-01

    The use of scrap tires in the coal blends is an alternative to reduction of coke production costs as well as mitigates the impact caused by tire accumulation in the environment. Tests were carried out on a pilot scale, with coal blends and waste tire in 4 levels and 3 particle sizes, in order to assess the impact on the produced coke quality, especially on the Strength after Reaction with CO2 - CSR and Drum Index (DI150-15). In addition, it evaluated the mechanical resistance to compression, ...

  12. Coke fouling process on the oil refining; Processo de incrustacao por coque no refino do petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Bombardelli, Clovis; Fiorentin, Leila D.; Negrao, Cezar O.R.; Franco, Admilson T. [Centro Federal de Educacao Tecnologica do Parana (CEFET-PR), Curitiba, PR (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica e de Materiais (PPGEM)

    2004-07-01

    The heavy crude fraction processing is performed under very high vacuum to minimize thermal cracking which cause coke deposition and damage the equipment. The current tendency is to process heavier oil leading to higher process temperatures and consequently to greater fouling. This situation demands better knowledge fouling process by carbonization. This problem is pronounced in the residual gasoil region of a vacuum distillation unit because it obstructs the recirculation circuits and the spray system with serious environmental and economics implications. This paper review the main correlated published work related to coke generation and fouling and presents a discussion about the works. (author)

  13. Minimum Quench Energy and Early Quench Development in NbTi Superconducting Strands

    CERN Document Server

    Breschi, M; Boselli, M; Bottura, Luca; Devred, Arnaud; Ribani, P L; Trillaud, F

    2007-01-01

    The stability of superconducting wires is a crucial task in the design of safe and reliable superconducting magnets. These magnets are prone to premature quenches due to local releases of energy. In order to simulate these energy disturbances, various heater technologies have been developed, such as coated tips, graphite pastes, and inductive coils. The experiments studied in the present work have been performed using a single-mode diode laser with an optical fiber to illuminate the superconducting strand surface. Minimum quench energies and voltage traces at different magnetic flux densities and transport currents have been measured on an LHC-type, Cu/NbTi wire bathed in pool boiling helium I. This paper deals with the numerical analysis of the experimental data. In particular, a coupled electromagnetic and thermal model has been developed to study quench development and propagation, focusing on the influence of heat exchange with liquid helium.

  14. Production of oil and coke from sludges containing organic pollutants; Gewinnung von Oel und Koks aus organisch belasteten Schlaemmen

    Energy Technology Data Exchange (ETDEWEB)

    Steger, M. [Martin Steger GmbH, Eggenfelden (Germany); Meissner, W.; Herold, R. [Max Aicher Umwelttechnik GmbH, Freilassing (Germany)

    1998-09-01

    Since the mid-eighties, Messrs. Max Aicher Umwelttechnik GmbH at Hammerau, Germany have been investigating sewage sludge pyrolysis. Laboratory experiments and semi-industrial investigations led to the construction of a combined sludge drying and conversion plant (``Aicher sludge recycling process``), in which the organic sludge fraction is converted into recyclable or combustible oils. Carbon is obtained as a by-product in solid form as conversion coke which can be utilized. Apart from sewage sludge, also industrial sludges with high organic fractions can be processed, e.g. sludges and sewage sludges from petroleum processing. (orig.) [Deutsch] In der Bundesrepublik Deutschland beschaeftigt sich die Max Aicher Umwelttechnik GmbH in Hammerau seit Mitte der Achtzigerjahre mit der Niedertemperaturkonvertierung (Pyrolyse) von Klaerschlamm. Versuche im Labor- und im halbtechnischen Massstab fuehrten zur Realisierung einer betriebstechnischen Anlage mit den Komponenten Schlammtrocknung und Konvertierung. Ziel des Aicher-Schlamm-Recycling-Verfahrens ist die Umwandlung der organischen Schlammfraktion in stofflich und energetisch verwertbare Oele. Bei der Umwandlung entsteht fixer Kohlenstoff, der im festen Rueckstand (Konversionskoks) angereichert wird. Neben dem gewonnenen Oel ist auch der produzierte Koks verwertbar. Einsatzstoffe fuer das Verfahren sind neben Klaerschlamm aus der kommunalen Abwasserreinigung vor allem industrielle Schlaemme mit hohen organischen Anteilen z.B. Schlaemme und Klaerschlaemme aus der Erdoelverarbeitung. (orig.)

  15. Catalytic evaluation of perovskite-type oxide LaNi{sub 1-x}Ru{sub x}O{sub 3} in methane dry reforming

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Genira Carneiro de [Grupo de Estudos em Cinetica e Catalise, Universidade Federal da Bahia, Campus Universitario de Ondina, Federacao, 40 170-290 Salvador, Bahia (Brazil); Instituto de Catalisis y Petroleoquimica, CSIC, Cantoblanco, 28049 Madrid (Spain); Lima, Sania Maria de; Assaf, Jose Mansur [Laboratorio de Catalise, Departamento de Engenharia Quimica, Universidade Federal de Sao Carlos, Sao Paulo (Brazil); Pena, Miguel Antonio; Fierro, Jose Luis Garcia [Instituto de Catalisis y Petroleoquimica, CSIC, Cantoblanco, 28049 Madrid (Spain); Do Carmo Rangel, Maria [Grupo de Estudos em Cinetica e Catalise, Universidade Federal da Bahia, Campus Universitario de Ondina, Federacao, 40 170-290 Salvador, Bahia (Brazil)

    2008-04-15

    The methane reforming with carbon dioxide (dry reforming) has been proposed as one of the most promising technologies for producing hydrogen by the use of two greenhouse gases. However, undesirable coke formation is the crucial issue to develop efficient catalysts for the reaction. In order to find alternative catalysts, which can be more resistant against coke deactivation, perovskite-type oxides LaRu{sub x}Ni{sub 1-x}O{sub 3} (0.0 < x < 1.0) were studied in this work. Samples were prepared by thermal decomposition of amorphous citrate precursors followed by heating at 800 or 1000 C, for 12 h, in air. The solids were characterized by X-ray diffraction, temperature-programmed reduction, temperature-programmed desorption, specific surface area measurements and X-ray photoelectron spectroscopy. The catalysts were reduced under hydrogen and tested in methane dry reforming at 1 atm and 750 C. The coke produced was characterized by thermogravimetry, carbon measurement and scanning and transmission electron microscopy. The oxide precursors showed low specific surface areas and different reducing behavior. All catalysts were active in the reaction. They all produced filamentous coke but it was not harmful to the catalysts. Nickel is more active and selective to hydrogen than ruthenium but the later improved the stability of the catalysts decreasing coke formation. The most promising catalyst was the LaNi{sub 0.8}Ru{sub 0.2}O{sub 3} sample, which was the most resistant against coke deposition. (author)

  16. Explaining jet quenching with perturbative QCD alone

    CERN Document Server

    Zapp, Korinna C; Wiedemann, Urs A

    2011-01-01

    We present a new formulation of jet quenching in perturbative QCD beyond the eikonal approximation. Multiple scattering in the medium is modelled through infra-red-continued (2 -> 2) scattering matrix elements in QCD and the parton shower describing further emissions. The interplay between these processes is arranged in terms of a formation time constraint such that coherent emissions can be treated consistently. Emerging partons are hadronised by the Lund string model, tuned to describe LEP data in conjunction with the parton shower. Based on this picture we obtain a good description of the nuclear modification factor R_AA at RHIC and LHC.

  17. Quench modeling of the ATLAS superconducting toroids

    CERN Document Server

    Gavrilin, A V; ten Kate, H H J

    2001-01-01

    Details of the normal zone propagation and the temperature distribution in the coils of ATLAS toroids under quench are presented. A tailor-made mathematical model and corresponding computer code enable obtainment of computational results for the propagation process over the coils in transverse (turn-to-turn) and longitudinal directions. The slow electromagnetic diffusion into the pure aluminum stabilizer of the toroid's conductor, as well as the essentially transient heat transfer through inter-turn insulation, is appropriately included in the model. The effect of nonuniform distribution of the magnetic field and the thermal links to the coil casing on the temperature gradients within the coils is analyzed in full. (5 refs).

  18. Quenching simulation of steel grinding balls

    Energy Technology Data Exchange (ETDEWEB)

    Zapata-Hernandez, O.; Reyes, L. A.; Camurri, C.; Carrasco, C.; Garza-Monte-de-Oca, F.; Colas, R.

    2015-07-01

    The phase transformations of high carbon steel during quenching and equalizing were modelled using commercial computer packages based on the finite element method and the kinetic transformation of steel. The model was used to predict the temperature and microstructural changes taking place within balls of two different sizes that are used for grinding mineral ores. A good correlation between the temperatures measured by inserted thermocouples and those predicted by the model was obtained after modifying the thermal conductivity of the steel within the temperature domain at which mixed phases are present. The phase transformations predicted were confirmed by metallographic analyses. (Author)

  19. Jet Quenching Measurements with ATLAS at LHC

    CERN Document Server

    Brooks, W K; The ATLAS collaboration

    2009-01-01

    A broad program of measurements is planned for heavy ion collisions in ATLAS. With up to a factor of 30 increase in collision energy compared to existing data, significant new insights are anticipated to be obtained with the first data measured. Global features of the LHC collisions will be accessible with the early data and will set the stage for the precision measurements to follow. ATLAS is particularly well suited for exploration of "jet quenching," the extinction of energetic jets in the hot dense medium. Observations of heavy quark jet suppression will be possible with unprecedented energy reach and statistical precision, potentially yielding new insights into the basic mechanisms involved.

  20. $B_{K}$ from quenched overlap QCD

    CERN Document Server

    Garron, N; Hölbling, C; Lellouch, L P; Rebbi, C

    2003-01-01

    We present an exploratory calculation of the standard model Delta S=2 matrix element relevant for indirect CP violation in K -> pi pi decays. The computation is performed with overlap fermions in the quenched approximation at beta=6.0 on a 16^3x32 lattice. The resulting bare matrix element is renormalized non-perturbatively. Our preliminary result is B_K^{NDR}(2 GeV)=0.61(7), where the error does not yet include an estimate of systematic uncertainties.

  1. Modelling of fluid flows in a coke-bed using thin-film models; Modellering af stroemningsforholdene i en koksbed vha. tyndfilmsmodeller

    Energy Technology Data Exchange (ETDEWEB)

    Kvist Jensen, T.; Henriksen, U.; Goebel, B.

    2002-02-01

    During this project dynamic models of a coke-bed have been built. The models are used to investigate how in-homogeneities influence fluid flows and coke conversion in the coke-bed. During thermal gasification of biomass in down draft gasifiers it has been observed that the coke under certain conditions is converted differently different places in the coke-bed. In extreme cases channels are even built down through the coke-bed. The varied conversion is bad for several reasons, partly because it is expected to indicate that the coke conversion is falling locally in the reactor and partly because some of the tar products from the pyrolysis will pass through the reactor without being cracked if channels have been made in the coke-bed. In connection with upgrading of gasifiers there is a risk that heterogeneous conditions in the coke-bed might arise resulting in the above-mentioned inconveniences. Thus, it is important to have a functional model for investigating how different operation parameters influence pressure conditions and hereby the conversion conditions in a coke-bed. The aim is to build models for description of fluid flows in a fixed bed reactor for gasification of biomass. The purpose with the models is to investigate how different parameters, e.g. particle size, porosity, and control strategies influence the stability of conversion in the coke bed. (BA)

  2. Electrical Resistivity Measurement of Petroleum Coke Powder by Means of Four-Probe Method

    Science.gov (United States)

    Rouget, G.; Majidi, B.; Picard, D.; Gauvin, G.; Ziegler, D.; Mashreghi, J.; Alamdari, H.

    2017-07-01

    Carbon anodes used in Hall-Héroult electrolysis cells are involved in both electrical and chemical processes of the cell. Electrical resistivity of anodes depends on electrical properties of its constituents, of which carbon coke aggregates are the most prevalent. Electrical resistivity of coke aggregates is usually characterized according to the ISO 10143 standardized test method, which consists of measuring the voltage drop in the bed of particles between two electrically conducing plungers through which the current is also applied. Estimation of the electrical resistivity of coke particles from the resistivity of particle bed is a challenging task and needs consideration of the contribution of the interparticle void fraction and the particle/particle contact resistances. In this work, the bed resistivity was normalized by subtracting the interparticle void fraction. Then, the contact size was obtained from discrete element method simulation and the contact resistance was calculated using Holm's theory. Finally, the resistivity of the coke particles was obtained from the bed resistivity.

  3. ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.

  4. Ceramic Lithium Ion Conductor to Solve the Anode Coking Problem of Practical Solid Oxide Fuel Cells.

    Science.gov (United States)

    Wang, Wei; Wang, Feng; Chen, Yubo; Qu, Jifa; Tadé, Moses O; Shao, Zongping

    2015-09-07

    For practical solid oxide fuel cells (SOFCs) operated on hydrocarbon fuels, the facile coke formation over Ni-based anodes has become a key factor that limits their widespread application. Modification of the anodes with basic elements may effectively improve their coking resistance in the short term; however, the easy loss of basic elements by thermal evaporation at high temperatures is a new emerging problem. Herein, we propose a new design to develop coking-resistant and stable SOFCs using Li(+) -conducting Li0.33 La0.56 TiO3 (LLTO) as an anode component. In the Ni/LLTO composite, any loss of surface lithium can be efficiently compensated by lithium diffused from the LLTO bulk under operation. Therefore, the SOFC with the Ni/LLTO anode catalyst layer yields excellent power outputs and operational stability. Our results suggest that the simple adoption of a Li(+) conductor as a modifier for Ni-based anodes is a practical and easy way to solve the coking problem of SOFCs that operate on hydrocarbons.

  5. Coke drums inspection and evaluation using stress and strain analysis techniques

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, Marcio Issamu [Tricom Tecnologia e Servicos de Manutencao Industrial Ltda., Piquete, SP (Brazil); Samman, Mahmod [Houston Engineering Solutions, Houston, TX (United States); Tinoco, Ediberto Bastos; Marangone, Fabio de Castro; Silva, Hezio Rosa da; Barcelos, Gustavo de Carvalho [Petroleo Brasileiro S.A. (PETROBRAS), Rio de Janeiro, RJ (Brazil)

    2012-07-01

    Coke drums deform due to a complex combination of mechanical and thermal cyclic stresses. Bulges have progressive behavior and represent the main maintenance problem related to these drums. Bulge failure typically result in through-wall cracks, leaks, and sometimes fires. Such failures generally do not represent a great risk to personnel. Repairs needed to maintain reliability of these vessels might require extensive interruption to operation which in turn considerably impacts the profitability of the unit. Therefore the condition, progression and severity of these bulges should be closely monitored. Coke drums can be inspected during turnaround with 3D Laser Scanning and Remote Visual Inspection (RVI) tools, resulting in a detailed dimensional and visual evaluation of the internal surface. A typical project has some goals: inspect the equipment to generate maintenance or inspection recommendations, comparison with previous results and baseline data. Until recently, coke drum structural analysis has been traditionally performed analyzing Stress Concentration Factors (SCF) thought Finite Element Analysis methods; however this technique has some serious technical and practical limitations. To avoid these shortcomings, the new strain analysis technique PSI (Plastic Strain Index) was developed. This method which is based on API 579/ ASME FFS standard failure limit represents the state of the art of coke drum bulging severity assessment has an excellent correlation with failure history. (author)

  6. Application of CyboCon Advanced Adjustment and Control Software Package in Delayed Coking Unit

    Institute of Scientific and Technical Information of China (English)

    Guo Hua

    2002-01-01

    This article refers to application of the CyboCon software package based upon the model-free adaptive control (MFA) in the 800-kt/a delayed coking unit to realize an advanced adjustment and control strategy for the temperature control of the heater. Operation tests have revealed the convenience in operating system and simplicity in maintenance, leading to good economic benefits.

  7. Lung cancer in an urban area in Northern Italy near a coke oven plant.

    Science.gov (United States)

    Parodi, Stefano; Stagnaro, Emanuele; Casella, Claudia; Puppo, Antonella; Daminelli, Enrico; Fontana, Vincenzo; Valerio, Federico; Vercelli, Marina

    2005-02-01

    Coke ovens are well-known sources of potentially carcinogenic air pollutants, but studies on resident populations are still poor. This study investigates the incidence of lung cancer near a coke oven in Cornigliano, a district of the Genoa municipality in Northern Italy. Genoa proper and one district similar to Cornigliano as regards socio-economic deprivation were selected as referents. Incidence data were drawn from the Ligurian Cancer Registry for 1986-1997 calendar period. Concentrations of pollutants related to the industrial activity (namely benzene, benzo[a]pyrene, PM(10), CO, NO(2) and SO(2)) were collected in selected locations before and after the coke oven closing. Spatial trend around the plant was assessed by Stone's test, while the pattern of risk across Cornigliano was evaluated via disease mapping in a Bayesian model. A gradient of air pollutants was observed around the coke oven, which disappeared after its closing. In Cornigliano, 158 lung cancer cases were observed in males and 28 in females. Only a marginal excess risk was observed versus the two selected referents, while a gradient in the areas close to the plant emerged among females. Disease mapping revealed another cluster of risk for both sexes in the Eastern part of the district, where a foundry was operative until the early 1980s. The excess risk for females is consistent with pollution measurements and with other epidemiological evidence. The geographic pattern of incidence suggests a role of industrial air pollution as a risk factor for lung cancer.

  8. Coke formation in the oxidative dehydrogenation of ethylbenzene to styrene by TEOM

    NARCIS (Netherlands)

    Nederlof, C.; Vijfhuizen, P.; Zarubina, V.; Melian-Cabrera, I.; Kapteijn, F.; Makkee, M.

    2014-01-01

    A packed bed microbalance reactor setup (TEOM-GC) is used to investigate the formation of coke as a function of time-on-stream on gamma-Al2O3 and 3P/SiO2 catalyst samples under different conditions for the ODH reaction of ethylbenzene to styrene. All samples show a linear correlation of the styrene

  9. Coke formation in the oxidative dehydrogenation of ethylbenzene to styrene by TEOM

    NARCIS (Netherlands)

    C. Nederlof; P. Vijfhuizen; V. Zarubina; I. Melián-Cabrera; F. Kapteijn; M. Makkee

    2014-01-01

    A packed bed microbalance reactor setup (TEOM-GC) is used to investigate the formation of coke as a function of time-on-stream on γ-Al2O3 and 3P/SiO2 catalyst samples under different conditions for the ODH reaction of ethylbenzene to styrene. All samples show a linear correlation of the styrene sele

  10. Reduction in toxicity of coking wastewater to aquatic organisms by vertical tubular biological reactor.

    Science.gov (United States)

    Zhou, Siyun; Watanabe, Haruna; Wei, Chang; Wang, Dongzhou; Zhou, Jiti; Tatarazako, Norihisa; Masunaga, Shigeki; Zhang, Ying

    2015-05-01

    We conducted a battery of toxicity tests using photo bacterium, algae, crustacean and fish to evaluate acute toxicity profile of coking wastewater, and to evaluate the performance of a novel wastewater treatment process, vertical tubular biological reactor (VTBR), in the removal of toxicity and certain chemical pollutants. A laboratory scale VTBR system was set up to treat industrial coking wastewater, and investigated both chemicals removal efficiency and acute bio-toxicity to aquatic organisms. The results showed that chemical oxygen demand (COD) and phenol reductions by VTBR were approximately 93% and 100%, respectively. VTBR also reduced the acute toxicity of coking wastewater significantly: Toxicity Unit (TU) decreased from 21.2 to 0.4 for Photobacterium phosphoreum, from 9.5 to 0.6 for Isochrysis galbana, from 31.9 to 1.3 for Daphnia magna, and from 30.0 to nearly 0 for Danio rerio. VTBR is an efficient treatment method for the removal of chemical pollutants and acute bio-toxicity from coking wastewater. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Sensory evaluation and electronic tongue analysis for sweetener recognition in coke drinks

    Science.gov (United States)

    Szöllősi, Dániel; Kovács, Zoltán; Gere, Attila; Sípos, László; Kókai, Zoltán; Fekete, András

    2011-09-01

    Consumption of beverages with low energy has an increasing role. Furthermore hydrolyzed starch products such as inverted syrup show a wide application in the beverage industry. Therefore the importance of methods which can monitor the usage of natural and artificial sweeteners is increasing. The task was to describe the relevant sensory attributes and to determine the applicability of the electronic tongue to discriminate the coke drink samples with different sweeteners. Furthermore the aim was to find relationship between the taste attributes and measurement results provided by electronic tongue. An Alpha Astree Electronic Tongue and a trained sensory panel were used to evaluate the coke samples. Panelists found significant differences between the samples in 15 cases from the 18 sensory attributes defined previously by the consensus group. Coke drinks containing different kind of sweeteners can be characterized according to these sensory attributes. The samples were definitely distinguished by the electronic tongue. The main difference was found between the samples made with natural and artificial sweeteners. However electronic tongue was able to distinguish samples containing different kind of artificial and different kind of natural sweeteners, as well. Taste attributes of coke drinks determined by sensory panel were predicted by partial least squares regression method based on the results of electronic tongue with close correlation and low prediction error.

  12. Electrical Resistivity Measurement of Petroleum Coke Powder by Means of Four-Probe Method

    Science.gov (United States)

    Rouget, G.; Majidi, B.; Picard, D.; Gauvin, G.; Ziegler, D.; Mashreghi, J.; Alamdari, H.

    2017-10-01

    Carbon anodes used in Hall-Héroult electrolysis cells are involved in both electrical and chemical processes of the cell. Electrical resistivity of anodes depends on electrical properties of its constituents, of which carbon coke aggregates are the most prevalent. Electrical resistivity of coke aggregates is usually characterized according to the ISO 10143 standardized test method, which consists of measuring the voltage drop in the bed of particles between two electrically conducing plungers through which the current is also applied. Estimation of the electrical resistivity of coke particles from the resistivity of particle bed is a challenging task and needs consideration of the contribution of the interparticle void fraction and the particle/particle contact resistances. In this work, the bed resistivity was normalized by subtracting the interparticle void fraction. Then, the contact size was obtained from discrete element method simulation and the contact resistance was calculated using Holm's theory. Finally, the resistivity of the coke particles was obtained from the bed resistivity.

  13. Predicting the amount of coke deposition on catalyst pellets through image analysis and soft computing

    Science.gov (United States)

    Zhang, Jingqiong; Zhang, Wenbiao; He, Yuting; Yan, Yong

    2016-11-01

    The amount of coke deposition on catalyst pellets is one of the most important indexes of catalytic property and service life. As a result, it is essential to measure this and analyze the active state of the catalysts during a continuous production process. This paper proposes a new method to predict the amount of coke deposition on catalyst pellets based on image analysis and soft computing. An image acquisition system consisting of a flatbed scanner and an opaque cover is used to obtain catalyst images. After imaging processing and feature extraction, twelve effective features are selected and two best feature sets are determined by the prediction tests. A neural network optimized by a particle swarm optimization algorithm is used to establish the prediction model of the coke amount based on various datasets. The root mean square error of the prediction values are all below 0.021 and the coefficient of determination R 2, for the model, are all above 78.71%. Therefore, a feasible, effective and precise method is demonstrated, which may be applied to realize the real-time measurement of coke deposition based on on-line sampling and fast image analysis.

  14. Who lives near coke plants and oil refineries An exploration of the environmental inequity hypothesis

    Energy Technology Data Exchange (ETDEWEB)

    Graham, J.D.; Beaulieu, N.D.; Sussman, D.; Sadowitz, M.; Li, Y.C. (Harvard Center for Risk Analysis, Boston, MA (United States))

    1999-04-01

    Facility-specific information on pollution was obtained for 36 coke plants and 46 oil refineries in the US and matched with information on populations surrounding these 82 facilities. These data were analyzed to determine whether environmental inequities were present, whether they were more economic or racial in nature, and whether the racial composition of nearby communities has changed significantly since plants began operations. The Census tracts near coke plants have a disproportionate share of poor and nonwhite residents. Multivariate analyses suggest that existing inequities are primarily economic in nature. The findings for oil refineries are not strongly supportive of the environmental inequity hypothesis. Rank ordering of facilities by race, poverty, and pollution produces limited (although not consistent) evidence that the more risky facilities tend to be operating in communities with above-median proportions of nonwhite residents (near coke plants) and Hispanic residents (near oil refineries). Over time, the radical makeup of many communities near facilities has changed significantly, particularly in the case of coke plants sited in the early 1900s. Further risk-oriented studies of multiple manufacturing facilities in various industrial sectors of the economy are recommended.

  15. 77 FR 15123 - Foundry Coke From China; Scheduling of an Expedited Five-Year Review

    Science.gov (United States)

    2012-03-14

    ... COMMISSION Foundry Coke From China; Scheduling of an Expedited Five-Year Review AGENCY: United States... its notice of institution (76 FR 74810, December 1, 2011) of the subject five-year review was adequate... information. Any person that is neither a party to the five-year review nor an interested party may submit a...

  16. Quench dynamics in SRF cavities: can we locate the quench origin with 2nd sound?

    Energy Technology Data Exchange (ETDEWEB)

    Maximenko, Yulia; /Moscow, MIPT; Segatskov, Dmitri A.; /Fermilab

    2011-03-01

    A newly developed method of locating quenches in SRF cavities by detecting second-sound waves has been gaining popularity in SRF laboratories. The technique is based on measurements of time delays between the quench as determined by the RF system and arrival of the second-sound wave to the multiple detectors placed around the cavity in superfluid helium. Unlike multi-channel temperature mapping, this approach requires only a few sensors and simple readout electronics; it can be used with SRF cavities of almost arbitrary shape. One of its drawbacks is that being an indirect method it requires one to solve an inverse problem to find the location of a quench. We tried to solve this inverse problem by using a parametric forward model. By analyzing the data we found that the approximation where the second-sound emitter is a near-singular source does not describe the physical system well enough. A time-dependent analysis of the quench process can help us to put forward a more adequate model. We present here our current algorithm to solve the inverse problem and discuss the experimental results.

  17. Final environmental information volume for the coke oven gas cleaning project at the Bethlehem Steel Corporation Sparrows Point Plant

    Energy Technology Data Exchange (ETDEWEB)

    1990-04-24

    Bethelehem Steel Corporation (BSC) is planning to conduct a demonstration project involving an integrated system that can be retrofitted into coke oven gas handling systems to address a variety of environmental and operational factors in a more cost-effective manner. Successful application of this technology to existing US coke plants could: (1) reduce emissions of sulfur dioxide, cyanide, and volatile organic compounds (including benzene) (2) reduce the cost and handling of processing feed chemicals, (3) disposal costs of nuisance by-products and (4) increase reliability and reduce operation/maintenance requirements for coke oven gas desulfurization systems. The proposed system will remove sulfur from the coke oven gas in the form of hydrogen sulfide using the ammonia indigenous to the gas as the primary reactive chemical. Ammonia and hydrogen cyanide are also removed in this process. The hydrogen sulfide removed from the coke oven gas in routed to a modified Claus plant for conversion to a saleable sulfur by-product. Ammonia and hydrogen cyanide will be catalytically converted to hydrogen, nitrogen, carbon dioxide, and carbon monoxide. The tail gas from the sulfur recovery unit is recycled to the coke oven gas stream, upstream of the new gas cleaning system. The proposed demonstration project will be installed at the existing coke oven facilities at BSC's Sparrows Point Plant. This volume describes the proposed actions and the resulting environmental impacts. 21 refs., 19 figs., 9 tabs.

  18. Nanostructured Multilayer Composite Coatings on Ceramic Cutting Tools for Finishing Treatment of High-Hardness Quenched Steels

    Science.gov (United States)

    Vereshchaka, A. A.; Batako, A. D.; Sotova, E. S.; Vereshchaka, A. S.

    2016-01-01

    The functional role of nanostructured multilayer composite coatings (NMCC) deposited on the operating surfaces of replaceable faceted cutting inserts (CI) from cutting ceramics based on aluminum oxides with additives of titanium carbides is studied. It is shown that the developed NMCC not only raise substantially the endurance of the ceramic tools under high-speed dry treatment of quenched steels but also improve the quality and accuracy of processing of the parts and the ecological parameters of the cutting process.

  19. Holographic quenches towards a Lifshitz point

    CERN Document Server

    Camilo, Giancarlo; Abdalla, Elcio

    2015-01-01

    We use the holographic duality to study quantum quenches of a strongly coupled CFT that drive the theory towards a non-relativistic fixed point with Lifshitz scaling. We consider the case of a Lifshitz dynamical exponent $z$ close to unity, where the non-relativistic field theory can be understood as a specific deformation of the corresponding CFT and, hence, the standard holographic dictionary can be applied. On the gravity side this amounts to finding a dynamical bulk solution which interpolates between AdS and Lishitz spacetimes as time evolves. We show that an asymptotically Lifshitz black hole is always formed in the final state. This indicates that it is impossible to reach the vacuum state of the Lifshitz theory from the CFT vacuum as a result of the proposed quenching mechanism. The nonequilibrium dynamics following the breaking of the relativistic scaling symmetry is also probed using both local and non-local observables. In particular, we conclude that the equilibration process happens in a top-down...

  20. Heat transfer model for quenching by submerging

    Energy Technology Data Exchange (ETDEWEB)

    Passarella, D N; Varas, F [Departamento de Matematica Aplicada II, E.T.S. de Ing. de Telecomunicacion, Universidad de Vigo, Campus Marcosende, 36310 Vigo (Spain); MartIn, E B, E-mail: diego@dma.uvigo.es, E-mail: fvaras@uvigo.es, E-mail: emortega@uvigo.es [Area de Mecanica de Fluidos, E.T.S. de Ing. Industriales, Universidad de Vigo, Campus Marcosende, 36310 Vigo (Spain)

    2011-05-01

    In quenching by submerging the workpiece is cooled due to vaporization, convective flow and interaction of both mechanisms. The dynamics of these phenomena is very complex and the corresponding heat fluxes are strongly dependent on local flow variables such as velocity of fluid and vapor fraction. This local dependence may produce very different cooling rates along the piece, responsible for inappropriate metallurgical transformations, variability of material properties and residual stresses. In order to obtain an accurate description of cooling during quenching, a mathematical model of heat transfer is presented here. The model is based on the drift-flux mixture-model for multiphase flows, including an equation of conservation of energy for the liquid phase and specific boundary conditions that account for evaporation and presence of vapor phase on the surface of the piece. The model was implemented on Comsol Multiphysics software. Generation of appropriate initial and boundary conditions, as well as numerical resolution details, is briefly discussed. To test the model, a simple flow condition was analyzed. The effect of vapor fraction on heat transfer is assessed. The presence of the typical vapor blanket and its collapse can be recovered by the model, and its effect on the cooling rates on different parts of the piece is analyzed. Comparisons between numerical results and data from literature are made.

  1. Quench thresholds in operational superconducting magnets

    Energy Technology Data Exchange (ETDEWEB)

    Allinger, J; Danby, G; Foelsche, H; Jackson, J; Lowenstein, D; Prodell, A; Weng, W

    1978-01-01

    Superconducting magnets exposed to intense primary proton beams in high energy physics applications are subject to potentially extreme heat deposition. The beam power density, its duration and spatial distribution, the current density in the superconductor and, potentially, in the normal metal substrate, as well as the construction and cooling details of the magnet, are all relevant parameters. An extension of some earlier work is discussed in which 28.5 GeV/c proton beams with up to 50 k joules of energy were targeted upstream from a 4 m long, 4 T dipole magnet used to deflect the protons through an angle of 8/sup 0/. Quench thresholds much greater than the enthalpy limit of the magnet materials were observed. In the beam exposure experiment described, intense beams of 1.5 GeV/c protons have been deflected directly into the magnet coil at relatively steep angles of incidence. The magnet quench threshold was studied by varying the beam currents and beam sizes.

  2. Quorum Quenching Revisited—From Signal Decays to Signalling Confusion

    Directory of Open Access Journals (Sweden)

    Kok-Gan Chan

    2012-04-01

    Full Text Available In a polymicrobial community, while some bacteria are communicating with neighboring cells (quorum sensing, others are interrupting the communication (quorum quenching, thus creating a constant arms race between intercellular communication. In the past decade, numerous quorum quenching enzymes have been found and initially thought to inactivate the signalling molecules. Though this is widely accepted, the actual roles of these quorum quenching enzymes are now being uncovered. Recent evidence extends the role of quorum quenching to detoxification or metabolism of signalling molecules as food and energy source; this includes “signalling confusion”, a term coined in this paper to refer to the phenomenon of non-destructive modification of signalling molecules. While quorum quenching has been explored as a novel anti-infective therapy targeting, quorum sensing evidence begins to show the development of resistance against quorum quenching.

  3. System and method for quench protection of a superconductor

    Science.gov (United States)

    Huang, Xianrui; Sivasubramaniam, Kiruba Haran; Bray, James William; Ryan, David Thomas

    2008-03-11

    A system and method for protecting a superconductor from a quench condition. A quench protection system is provided to protect the superconductor from damage due to a quench condition. The quench protection system comprises a voltage detector operable to detect voltage across the superconductor. The system also comprises a frequency filter coupled to the voltage detector. The frequency filter is operable to couple voltage signals to a control circuit that are representative of a rise in superconductor voltage caused by a quench condition and to block voltage signals that are not. The system is operable to detect whether a quench condition exists in the superconductor based on the voltage signal received via the frequency filter and to initiate a protective action in response.

  4. Bridging global and local quantum quenches in conformal field theories

    CERN Document Server

    Wen, Xueda

    2016-01-01

    Entanglement evolutions after a global quantum quench and a local quantum quench in 1+1 dimensional conformal field theories (CFTs) show qualitatively different behaviors, and are studied within two different setups. In this work, we bridge global and local quantum quenches in (1+1)-d CFTs in the same setup, by studying the entanglement evolution from a specific inhomogeneous initial state. By utilizing conformal mappings, this inhomogeneous quantum quench is analytically solvable. It is found that the entanglement evolution shows a global quantum quench feature in the short time limit, and a local quantum quench feature in the long time limit. The same features are observed in single-point correlation functions of primary fields. We provide a clear physical picture for the underlying reason.

  5. Variation of Quench Propagation Velocities in YBCO Cables

    CERN Document Server

    Härö, E.; Stenvall, A.; 10.1007/s10948-015-2976-y

    2015-01-01

    changes during the quench. Due to the large temperature margin between the operation and the current sharing temperatures, the normal zone does not propagate with the temperature front. This means that the temperature will rise in a considerably larger volume when compared to the quenched volume. Thus, the evolution of the temperature distribution below current sharing temperature Tcs after the quench onset affects the normal zone propagation velocity in HTS more than in LTS coils. This can be seen as an acceleration of the quench propagation velocities while the quench evolves when margin to Tcs is high. In this paper we scrutinize quench propagation in a stack of YBCO cables with an in-house finite element method software which solves the heat diffusion equation. We compute the longitudinal and transverse normal zone propagation velocities at various distances from the hot spot to demonstrate the distance-variation...

  6. Coke, char and organic waste behaviour in the blast furnace with high injection rate

    Directory of Open Access Journals (Sweden)

    Gudenau, H. W.

    2003-10-01

    Full Text Available Blast furnace operation with low coke rate, high amount of auxiliary hydrocarbons and use of nut coke causes a change in coke quality requirements. In particular, not burned in the raceway residues of injected substances (char and ash can influence the coke behaviour. Therefore combustion efficiency of various organic wastes with and without pulverized coal injection (PCI and coal char has been investigated under the raceway simulation conditions. Mixing of various substances improves their combustion efficiency. Study on coke gasification by carbon dioxide in the presence of char showed that with the increase of char concentration, coke strength reduction becomes smaller. The reactivity of char with CO2 is higher than that of coke. Therefore char is consumed preferentially. In presence of injected char, total pore volume in coke and its wear resistance were increased. Coke reactivity and microstructure in the presence of various kinds of ash has been studied. Many ash spheres were observed on the surface of coke matrix and its size was dependent on ash properties.

    La operación del horno alto con una tasa baja de coque, una cantidad elevada de hidrocarburos auxiliares y el empleo de coque calibrado, origina un cambio en las necesidades de calidad del coque. En particular, pueden influir en el comportamiento del coque los residuos inquemados en el raceway (cavidad enfrente a las toberas del horno de las sustancias que se inyectan (char y cenizas. El char es el residuo de carbón que se origina después que el carbón libera sus sustancias volátiles. Por tanto, se ha investigado la eficiencia de la combustión de varios residuos orgánicos con y sin inyección de carbón pulverizado (ICP y char, bajo las condiciones de simulación del raceway. La mezcla de varias sustancias mejora la eficiencia a la combustión. El estudio de la gasificación del coque por el dióxido de carbono en la

  7. Holographic study on the jet quenching parameter in anisotropic systems

    CERN Document Server

    Wang, Luying

    2016-01-01

    We first calculate the jet quenching parameter of an anisotropic plasma with a U(1) chemical potential via the AdS/CFT duality. The effects of charge, anisotropy parameter and quark motion direction on the jet quenching parameter are investigated. We then discuss the situation of anisotropic black brane in the IR region. We study both the jet quenching parameters along the longitudinal direction and transverse plane.

  8. Holographic study of the jet quenching parameter in anisotropic systems

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Luying [Shanghai University, Department of Physics, Shanghai (China); Wu, Shang-Yu [National Chiao Tung University, Department of Electrophysics, Hsinchu (China)

    2016-11-15

    We first calculate the jet quenching parameter of an anisotropic plasma with a U(1) chemical potential via AdS/CFT duality. The effects of charge, anisotropy parameter, and quark motion direction on the jet quenching parameter are investigated. We then discuss the situation of an anisotropic black brane in the IR region. We study both the jet quenching parameters along the longitudinal direction and the transverse plane. (orig.)

  9. Coke state determination in the blast furnace hearth using a tuyere probe

    Energy Technology Data Exchange (ETDEWEB)

    Negro, P.; Pierret, H.; Steiler, J.M. (Institut de Recherches de la Siderurgie Francaise (IRSID), 78 - Saint-Germain-en-Laye (France)); Lao, D.; Eymond, J.L.; Fauchoit, P. (Sollac, 59 - Dunkerque (France)); Eibes, C.; Blaise, G.; Urvoy, A.; Helleisen, M.; Giroldini, F.; Hartig, M.; Rausch, H.

    1993-04-01

    Coke samplings at blast furnace tuyeres are a powerful mean to study the behaviour of the lower part of the furnace. A tuyere probe has been installed since April 1985 on the BF 2 at Sollac Fos. This probe is 19 m long and 11 tons weight. It uses a 265 mm internal diameter pipe which samples materials until the centre of the BF. Up-to-now, 28 trials have been completed. The results obtained with this probe allow: a better understanding of the phenomena occurring in the blast furnace hearth, to establish several relationships between the internal state of the hearth and the operation conditions, to build and validate a new image of the cohesive zone and the coke state, to measure and understand the influence of coal injection on the BF operation. Since April 1991, a movable tuyere probe has been in operation within Usinor Sacilor Group. This machine is more lighter than the fixed one weighing only 5.5 tons and smaller measuring 5 m long for 1.3 m width. The probe is a 260 mm internal diameter pipe which can be introduced for 4.25 m in the furnace. In 20 months, it is more than 40 coke core borings which have been achieved on 9 different furnaces of 4 different plants. These two probes are complementary. The fixed probe is only used through one tuyere of one BF. In addition, this probe can reach the centre of the furnace and give a complete description of the materials present along the radius. The movable machine cannot reach the centre of the BF, but it authorizes the study of: some very different BF operating conditions, the influence of the feed materials qualities in a large range, the heterogeneity between several tuyeres of one BF, the effect of the BF size. This text presents our approach in coke quality research, relying upon the results of coke core borings. 6 refs., 17 figs.

  10. Coke state determination in the blast furnace hearth using a tuyere probe

    Energy Technology Data Exchange (ETDEWEB)

    Negro, P.; Pierret, H.; Steiler, J. [and others] [Institut de Recherches de la Siderurgie Francaise (IRSID), Saint-Germain-en-Laye (France)

    1996-11-01

    Coke samplings at blast furnace tuyeres are a powerful means to study the behaviour of the lower part of the furnace. A tuyere probe has been installed since April 1985 on the BF2 at Sollac Fos. This probe is 19 m long and 11 tons in weight. It uses a 265 mm internal diameter pipe which samples materials in the centre of the BF. Up to now, 28 trials have been completed. The results obtained allow: a better understanding of the phenomena occurring in the blast furnace hearth, to establish several relationships between the internal state of the hearth and operation conditions, to build and validate a new image of the cohesive zone and the coke state, to measure and understand the influence of coal injection on the BF operation. Since April 1991, a movable tuyere probe has been in operation within Usinor Sacilor Group. This machine is lighter than the fixed one weighing only 5.5 tons and smaller measuring 5 m long for 1.3 m width. The probe is a 260 mm internal diameter pipe which can be introduced 4.25 m into the furnace. In 20 months, more than 40 coke core borings have been achieved on 9 different furnaces in 4 different plants. These two probes are complementary. The fixed probe is only used through one tuyere of one BF. In addition, this probe can reach the centre of the furnace and give a complete description of the materials present along the radius. The movable machine cannot reach the centre of the BF, but it enables the study of: some very different BF operating conditions, the influence of the feed materials qualities in a large range, the heterogeneity between several tuyeres of one BF, and the effect of the BF size. This paper presents an approach in coke quality research, relying upon the results of coke core borings.

  11. Variations in toxicity of semi-coking wastewater treatment processes and their toxicity prediction.

    Science.gov (United States)

    Ma, Xiaoyan; Wang, Xiaochang; Liu, Yongjun; Gao, Jian; Wang, Yongkun

    2017-04-01

    Chemical analyses and bioassays using Vibrio fischeri and Daphnia magna were conducted to evaluate comprehensively the variation of biotoxicity caused by contaminants in wastewater from a semi-coking wastewater treatment plant (WWTP). Pretreatment units (including an oil-water separator, a phenols extraction tower, an ammonia stripping tower, and a regulation tank) followed by treatment units (including anaerobic-oxic treatment units, coagulation-sedimentation treatment units, and an active carbon adsorption column) were employed in the semi-coking WWTP. Five benzenes, 11 phenols, and five polycyclic aromatic hydrocarbons (PAHs) were investigated as the dominant contaminants in semi-coking wastewater. Because of residual extractant, the phenols extraction process increased acute toxicity to V. fischeri and immobilization and lethal toxicity to D. magna. The acute toxicity of pretreated wastewater to V. fischeri was still higher than that of raw semi-coking wastewater, even though 90.0% of benzenes, 94.8% of phenols, and 81.0% of PAHs were removed. After wastewater pretreatment, phenols and PAHs were mainly removed by anaerobic-oxic and coagulation-sedimentation treatment processes respectively, and a subsequent active carbon adsorption process further reduced the concentrations of all target chemicals to below detection limits. An effective biotoxicity reduction was found during the coagulation-sedimentation and active carbon adsorption treatment processes. The concentration addition model can be applied for toxicity prediction of wastewater from the semi-coking WWTP. The deviation between the measured and predicted toxicity results may result from the effects of compounds not detectable by instrumental analyses, the synergistic effect of detected contaminants, or possible transformation products. Copyright © 2016. Published by Elsevier Inc.

  12. Quenching of porous silicon photoluminescence by deposition of metal adsorbates

    Energy Technology Data Exchange (ETDEWEB)

    Andsager, D.; Hilliard, J.; Hetrick, J.M.; AbuHassan, L.H.; Plisch, M.; Nayfeh, M.H. (Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801 (United States))

    1993-10-01

    Various metals were deposited on luminescent porous silicon (PS) by immersion in metal ion solutions and by evaporation. The photoluminescence (PL) was quenched upon immersion in ionic solutions of Cu, Ag, and Au but not noticeably quenched in other ionic solutions. Evaporation of 100 A of Cu or 110 A of Au was not observed to quench PL. Auger electron spectroscopy performed on samples quenched and then immediately removed from solution showed a metallic concentration in the PS layer of order 10 at.%, but persisting to a depth of order 3000 A.

  13. Luminescence Decay Times and Bimolecular Quenching: An Ultrafast Kinetics Experiment

    Science.gov (United States)

    Demas, J. N.

    1976-01-01

    Describes the theory, apparatus, and procedure for an experiment that measures the bimolecular quenching constant for the deactivation of an excited ruthenium ion complex using dissolved oxygen. (MLH)

  14. Quench Analysis of the PANDA Target Spectrometer Solenoid

    CERN Document Server

    Deelen, Nikkie

    2014-01-01

    A quench analysis of the PANDA Target Solenoid has been performed. The characteristic time of the fast discharge is $12\\ \\text{s}$. The peak temperature and peak voltage during a quench are $30\\ \\text{K}$ and $160\\ \\text{V}$ respectively. During a quench the energy stored in the magnetic field is mostly dissipated in the dump resistor. The slow discharge of the PANDA solenoid takes approximately $1950\\ \\text{s}$ during which nearly all the energy is dissipated in the diodes of the quench protection circuit.

  15. Quenching of fluorescence in membrane protein by hypocrellin B.

    Science.gov (United States)

    Yue, J; Pang, S

    1997-04-01

    The hypocrellin B (HB) was used as a fluorescence quencher to study the basic physical charactcristics of HB in membrane systems, including the diffusion speed of quencher from aqueous phase into membrane phase, the partition coefficient (P) of quenchtr between membrane and water, and the fluorescence quenching constant of protein (K(sv); K(q),). The experimental results show that the quenching of fluorescence in membrane protein by HB can be determined by the principle of dynamic quenching. The experimental process of fluorescence quenching was observed in detail by using the ESR technique. The signal of HB- was found to arise from an electron transfer from excited trytophan to HB.

  16. Quenching of fluorescence in membrane protein by hypocrellin B

    Institute of Scientific and Technical Information of China (English)

    乐加昌; 庞素珍

    1997-01-01

    The hypocrellin B (HB) was used as a fluorescence quencher to study the basic physical characteris-tics of HB in membrane systems, including the diffusion speed of quencher from aqueous phase into membrane phase, the partition coefficient (P) of quencher between membrane and water, and the fluorescence quenching constant of protein (Ksv; Kq). The experimental results show that the quenching of fluorescence in membrane protein by HB can be determined by the principle of dynamic quenching. The experimental process of fluorescence quenching was ob-served in detail by using the ESR technique. The signal of HB" was found to arise from an electron transfer from ex-cited trytophan to HB.

  17. Optimising Gas Quenching Technology through Modelling of Heat Transfer

    Institute of Scientific and Technical Information of China (English)

    Florent Chaffotte; Linda L(e)fevre; Didier Domergue; Aymeric Goldsteinas; Xavier Doussot; Qingfei Zhang

    2004-01-01

    Gas Quenching represents an environmentally friendly alternative to more commonly-used oil quenching. Yet,the performances of this technology remain limited in terms of cooling rates reached compared to oil quenching. Distortion and process homogeneity also have to be controlled carefully. The efficiency of the gas quenching process fully depends on the heat transfer between the gas and the quenched parts. The goal of this study is the optimisation of the gas quenching process efficiency through a better understanding of the heat transfer phenomena involved. The study has been performed with modelling means and validated by an experimental approach. The configuration of the gas flow has a major influence on the heat transfer phenomena between the gas and the parts. The fluid dynamics modelling approach performed in this study allows to optimise the heat transfer phenomena. New gas quenching processes allowing enhanced gas quenching performance through higher cooling rates can be thereby identified. The new solutions have been validated in experimental and industrial conditions. Results obtained allow to expect significant improvement of high pressure gas quenching technology.

  18. Numerical Simulation on Carburizing and Quenching of Gear Ring

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The carburizing process of the gear ring was simulated by taking into account the practical carburizing and quenching techniques of the gear ring and by solving the diffusion equation. The carbon content distribution in the carburized layer was obtained. Based on the results, the quenching process of the gear ring was then simulated using the metallic thermodynamics and FEM; it was found that the carburization remarkably affects the quenching process.Microstructures and stress distributions of the gear ring in the quenching process were simulated, and the results are confirmed by experiments.

  19. Optimising Gas Quenching Technology through Modelling of Heat Transfer

    Institute of Scientific and Technical Information of China (English)

    FiorentChaffotte; LindaLefevre; DidierDomergue; AymericGoidsteinas; XavierDoussot; QingfeiZhang

    2004-01-01

    Gas Quenching represents an environmentally friendly alternative to more commonly-used oil quenching. Yet,the performances of this technology remain limited in terms of cooling rates reached compared to oil quenching. Distortion and process homogeneity also have to be controlled carefully. The efficiency of the gas quenching process fully depends on the heat transfer between the gas and the quenched parts. The goal of this study is the optimisation of the gas quenching process efficiency through a better understanding of the heat transfer phenomena involved. The study has been performed with modelling means and validated by an experimental approach. ThE configuration of the gas flow has a major influence on the heat transfer phenomena between the gas and the parts. The fluid dynamics modelling approach performed in this study allows to optimise the heat transfer phenomena. New gas quenching processes allowing enhanced gas quenching performance through higher cooling rates can be thereby identified. The new solutions have been validated in experimental and industrial conditions. Results obtained allow to expect significant improvement of high pressure gas quenching technology.

  20. Experimental methods for quenching structures in lunar-analog silicate melts: Variations as a function of quench media and composition

    Science.gov (United States)

    Dyar, M. D.

    1985-01-01

    Compositions analogous to lunar green, organge, and brown glasses were synthesized under consistent conditions, then quenched into a variety of different media when the samples were removed from the furnace. Iron valence and coordination are a direct function of quench media used, spanning the range from brine/ice (most effective quench), water, butyl phthalate, silicone oil, liquid nitrogen, highly reducing CO-CO2 gas, to air (least efficient quench). In the green and brown glasses, Fe(3+) in four-fold and six-fold coordination is observed in the slowest-quenched samples; Fe(2+) coordination varies directly with quench efficiency. Less pronounced changes were observed in the Ti-rich orange glass. Therefore the remote-sensed spectrum of a glass-bearing regolith on the Moon may be influenced by the process by which the glass cooled, and extreme caution must be used when comparing spectra of synthetic glass analogs with real lunar glasses.

  1. Experimental methods for quenching structures in lunar-analog silicate melts - Variations as a function of quench media and composition

    Science.gov (United States)

    Dyar, M. D.

    1984-01-01

    Compositions analogous to lunar green, orange, and brown glasses were synthesized under consistent conditions, then quenched into a variety of different media when the samples were removed from the furnace. Iron valence and coordination are a direct function of quench media used, spanning the range from brine/ice (most effective quench), water, butyl phthalate, silicone oil, liquid nitrogen, highly reducing CO-CO2 gas, to air (least efficient quench). In the green and brown glasses, Fe(3+) in four-fold and six-fold coordination is observed in the slowest-quenched samples; Fe(2+) coordination varies directly with quench efficiency. Less pronounced changes were observed in the Ti-rich orange glass. Therefore the remote-sensed spectrum of a glass-bearing regolith on the moon may be influenced by the process by which the glass cooled, and extreme caution must be used when comparing spectra of synthetic glass analogs with real lunar glasses.

  2. Coke Formation During Hydrocarbons Pyrolysis. Part Two: Methane Thermal Cracking Formation de coke pendant la pyrolyse des hydrocarbures. Deuxième partie : pyrolyse du méthane

    Directory of Open Access Journals (Sweden)

    Billaud F.

    2006-11-01

    Full Text Available Part one of this article dealt with coking in a steam cracking furnace. In this process, coke deposition is a very complex phenomenon due to the number of parameters involved. Nevertheless, for this process, coke deposition is a secondary reaction which does not affect steam cracking yields. It is completely different for methane thermal cracking. Coke is one of the main products of this reaction. Part two of this article deals with coke deposition on the walls of the reactors used for methane thermal cracking. After a brief description of the different set-ups used to study coke deposition, the main parameters involved are listed. The importance of temperature, conversion, type of diluent, and hydrocarbon partial pressure will be enhanced. To conclude, two approaches to the mechanism are proposed to explain coke formation during methane thermal cracking. La première partie de cet article faisait le point sur les réactions indésirables de cokage dans les réacteurs de vapocraquage : dans le cadre de ce procédé, la formation de coke est un phénomène complexe du fait du nombre important de paramètres mis en jeu. Toutefois, pour ce procédé, la réaction de formation du coke à la paroi des réacteurs est une réaction secondaire qui n'affecte pas les rendements de vapocraquage. Ceci est complètement différent dans le cas de la pyrolyse thermique du méthane, procédé pour lequel le coke est un produit principal et indésirable de la réaction. La seconde partie de cet article est consacrée plus particulièrement à la formation du coke, lors de la pyrolyse du méthane et présente les principaux résultats expérimentaux décrits dans la littérature. Parmi les différents montages expérimentaux utilisés pour mesurer le dépôt de coke, il est mentionné, à partir des travaux de la littérature, les 2 techniques suivantes : - la technique de la paroi chaude, - la technique du fil chaud. Pour la première technique, les montages exp

  3. A perturbative framework for jet quenching

    CERN Document Server

    Zapp, Korinna C; Wiedemann, Urs A

    2013-01-01

    We present a conceptually new framework for describing jet evolution in the dense medium produced in ultra-relativistic nucleus-nucleus collisions using perturbative QCD and its implementation into the Monte Carlo event generator JEWEL. The rescattering of hard partons in the medium is modelled by infrared continued pQCD matrix elements supplemented with parton showers. The latter approximate higher order real-emission matrix elements and thus generate medium-induced gluon emissions. The interplay between different emissions is governed by their formation times. The destructive interference between subsequent scattering processes, the non-Abelian version of the Landau-Pomeranchuk-Migdal effect, is also taken into account. In this way the complete radiation pattern is consistently treated in a uniform way. Results obtained within this minimal and theoretically well constrained framework are compared with a variety of experimental data susceptible to jet-quenching effects at both RHIC and the LHC. Overall, a go...

  4. Response functions after a quantum quench

    Science.gov (United States)

    Marcuzzi, Matteo; Gambassi, Andrea

    2014-04-01

    The response of physical systems to external perturbations can be used to probe both their equilibrium and nonequilibrium dynamics. While response and correlation functions are related in equilibrium by fluctuation-dissipation theorems, out of equilibrium they provide complementary information on the dynamics. In the past years, a method has been devised to map the quantum dynamics of an isolated extended system after a quench onto a static theory with boundaries in imaginary time; up to now, however, the focus was entirely on symmetrized correlation functions. Here we provide a prescription which, in principle, allows one to retrieve the whole set of relevant dynamical quantities characterizing the evolution, including linear response functions. We illustrate this construction with some relevant examples, showing in the process the emergence of light-cone effects similar to those observed in correlation functions.

  5. How Cosmic Web Detachment Drives Galaxy Quenching

    CERN Document Server

    Aragon-Calvo, Miguel A; Silk, Joseph

    2016-01-01

    We present the Cosmic Web Detachment (CWD) model, a conceptual framework to interpret galaxy evolution in a cosmological context, providing a direct link between the star formation history of galaxies and the cosmic web. The CWD model unifies several mechanism known to disrupt or stop star formation into one single physical process and provides a natural explanation for a wide range of galaxy properties. Galaxies begin accreting star-forming gas at early times via a network of primordial highly coherent filaments. The efficient star formation phase ends when non-linear interactions with other galaxies or elements of the cosmic web detach the galaxy from its network of primordial filaments, thus ending the efficient accretion of cold gas. The stripping of the filamentary web around galaxies is the physical process responsible of star formation quenching in gas stripping, harassment, strangulation and starvation. Being a purely gravitational/mechanical process CWD acts at a more fundamental level than internal ...

  6. Thermal quenching of luminescence processes in feldspars

    DEFF Research Database (Denmark)

    Poolton, N.R.J.; Bøtter-Jensen, L.; Duller, G.A.T.

    1995-01-01

    The technique of optically stimulated luminescence has important uses in the dose evaluation of irradiated feldspars. The luminescence process involves the eviction of electrons from donor traps, charge transfer through the conduction band, and recombination at acceptor sites; each...... of these processes is, in general, thermally dependent, and leads either to enhancement or quenching of the luminescence with increasing temperature. Previous studies have measured the combined thermal activation characteristics of all three processes, and show a strong dependence on stimulation energy....... In this article, an initial attempt is made to isolate only the recombination part of the luminescence cycle, and determine its thermal characteristics separately. A Variety of luminescence transitions are examined in a range of both alkali and plagioclase feldspars; three distinct emission types are identified...

  7. Charmonium properties in hot quenched lattice QCD

    CERN Document Server

    Ding, H -T; Kaczmarek, O; Karsch, F; Satz, H; Soeldner, W

    2012-01-01

    We study the properties of charmonium states at finite temperature in quenched QCD on large and fine isotropic lattices. We perform a detailed analysis of charmonium correlation and spectral functions both below and above $T_c$. Our analysis suggests that both S wave states ($J/\\psi$ and $\\eta_c$) and P wave states ($\\chi_{c0}$ and $\\chi_{c1}$) disappear already at about $1.5 T_c$. The charm diffusion coefficient is estimated through the Kubo formula and found to be compatible with zero below $T_c$ and approximately $1/\\pi T$ at $1.5 T_c\\lesssim T\\lesssim 3 T_c$.

  8. Charmonium properties in hot quenched lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Ding, H. -T.; Francis, A.; Kaczmarek, O.; Karsch, F.; Satz, H.; Soeldner, W.

    2012-07-01

    We study the properties of charmonium states at finite temperature in quenched QCD on large and fine isotropic lattices. We perform a detailed analysis of charmonium correlation and spectral functions both below and above Tc. Our analysis suggests that both S wave states (J/ψ and ηc) and P wave states (χc0 and χc1) disappear already at about 1.5Tc. The charm diffusion coefficient is estimated through the Kubo formula and found to be compatible with zero below Tc and approximately 1/πT at 1.5Tc≲T≲3Tc.

  9. Thermal dilepton rates from quenched lattice QCD

    CERN Document Server

    Ding, H -T; Kaczmarek, O; Karsch, F; Laermann, E; Mukherjee, S; Müller, M; Soeldner, W

    2013-01-01

    We present new lattice results on the continuum extrapolation of the vector current correlation function. Lattice calculations have been carried out in the deconfined phase at a temperature of 1.1 Tc, extending our previous results at 1.45 Tc, utilizing quenched non-perturbatively clover-improved Wilson fermions and light quark masses. A systematic analysis on multiple lattice spacings allows to perform the continuum limit of the correlation function and to extract spectral properties in the continuum limit. Our current analysis suggests the results for the electrical conductivity are proportional to the temperature and the thermal dilepton rates in the quark gluon plasma are comparable for both temperatures. Preliminary results of the continuum extrapolated correlation function at finite momenta, which relates to thermal photon rates, are also presented.

  10. Quenching Simulation of PM Coated Tools

    Institute of Scientific and Technical Information of China (English)

    AxelHoftert; WernerTheisen; ChristophBroeckmann

    2004-01-01

    HIP cladding is a powder metallurgical coating technique used in the production of wear parts and tools. In many cases the composite components consist of carbide-free hot-work steel as base material and wear resistant carbide-rich PM cold-work steel as coating material. To ensure operativeness a heat tleatment matched to the substrate and coating material is required. Dissimilar phase tlansformation behaviour and different thermal expansion coefficients of layer and substrate entail inner stresses affecting the tlansformation kinetics in tam. In order to get a deeper insight into these effects Finite Element simulation tools are used. On the one hand, the tlansient heat conduction problem of the quenching process has to be solved. Non-linear boundary conditions and phase transformation of both, substrate and layer are considered. On the other hand, the mechanical response is calculated. The overall aim of the investigation is an improvement of common heat treatment techniques used for HIP cladded wear parts.

  11. Quenching Simulation of PM Coated Tools

    Institute of Scientific and Technical Information of China (English)

    Axel H(o)fter; Werner Theisen; Christoph Broeckmann

    2004-01-01

    HIP cladding is a powder metallurgical coating technique used in the production of wear parts and tools. In many cases the composite components consist of carbide-free hot-work steel as base material and wear resistant carbide-rich PM cold-work steel as coating material. To ensure operativeness a heat treatment matched to the substrate and coating material is required. Dissimilar phase transformation behaviour and different thermal expansion coefficients of layer and substrate entail inner stresses affecting the transformation kinetics in turn. In order to get a deeper insight into these effects Finite Element simulation tools are used. On the one hand, the transient heat conduction problem of the quenching process has to be solved. Non-linear boundary conditions and phase transformation of both, substrate and layer are considered. On the other hand, the mechanical response is calculated. The overall aim of the investigation is an improvement of common heat treatment techniques used for HIP cladded wear parts.

  12. Magnetic Barkhausen Noise in quenched carburized steels

    Energy Technology Data Exchange (ETDEWEB)

    De Campos, M F; Santos, R; Da Silva, F S; Lins, J F C [PUVR- Universidade Federal Fluminense, Av dos Trabalhadores 420, Vila Santa Cecilia, Volta Redonda, RJ, 27255-125 (Brazil); Franco, F A; Ribeiro, S B; Padovese, L R, E-mail: mcampos@metal.eeimvr.uff.br, E-mail: mfdcampo@uol.com.br [Escola Politecnica, Universidade de Sao Paulo, Sao Paulo, SP (Brazil)

    2011-07-06

    Steels with different carbon content, 0.11%C and 0.48%C were submitted to a heat treatment for carburization in the surface. The samples were analyzed after several types of heat treatment, including quenching for producing martensite. The Magnetic Barkhausen Noise (MBN) is directly related to the microstructure. Samples with lower carbon content, have ferrite, a constituent where domain walls can move freely and present higher amplitude in the envelope of MBN. It is also found that the MBN peaks are quite distinct for the samples with martensite, which have lower permeability, and the results suggest that domain rotation contributes as mechanism for reversal of magnetization in martensite. The results also indicate that MBN is very suitable for monitoring the carburizing heat treatment.

  13. Magnetic Barkhausen Noise in quenched carburized steels

    Science.gov (United States)

    de Campos, M. F.; Franco, F. A.; Santos, R.; da Silva, F. S.; Ribeiro, S. B.; Lins, J. F. C.; Padovese, L. R.

    2011-07-01

    Steels with different carbon content, 0.11%C and 0.48%C were submitted to a heat treatment for carburization in the surface. The samples were analyzed after several types of heat treatment, including quenching for producing martensite. The Magnetic Barkhausen Noise (MBN) is directly related to the microstructure. Samples with lower carbon content, have ferrite, a constituent where domain walls can move freely and present higher amplitude in the envelope of MBN. It is also found that the MBN peaks are quite distinct for the samples with martensite, which have lower permeability, and the results suggest that domain rotation contributes as mechanism for reversal of magnetization in martensite. The results also indicate that MBN is very suitable for monitoring the carburizing heat treatment.

  14. Collisional quenching of highly rotationally excited HF

    CERN Document Server

    Yang, Benhui; Forrey, R C; Stancil, P C; Balakrishnan, N

    2015-01-01

    Collisional excitation rate coefficients play an important role in the dynamics of energy transfer in the interstellar medium. In particular, accurate rotational excitation rates are needed to interpret microwave and infrared observations of the interstellar gas for nonlocal thermodynamic equilibrium line formation. Theoretical cross sections and rate coefficients for collisional deexcitation of rotationally excited HF in the vibrational ground state are reported. The quantum-mechanical close-coupling approach implemented in the nonreactive scattering code MOLSCAT was applied in the cross section and rate coefficient calculations on an accurate 2D HF-He potential energy surface. Estimates of rate coefficients for H and H$_2$ colliders were obtained from the HF-He collisional data with a reduced-potential scaling approach. The calculation of state-to-state rotational quenching cross sections for HF due to He with initial rotational levels up to $j=20$ were performed for kinetic energies from 10$^{-5}$ to 15000...

  15. Thermal quenching of fluorescence in condensed media

    Science.gov (United States)

    Lagos, Miguel; Paredes, Rodrigo

    2016-09-01

    Environmental factors strongly affect the features of the electromagnetic spectra of fluorescent compounds hosted by material media. The shape of the absorption and emission peaks, their characteristic asymmetry and breadth, the Stokes shift and quantum yield are generally temperature dependent and heavily influenced by both the local and extended physical properties of the medium. The theoretical method used before to obtain the lineshape function is extended here to other terms of the interaction energy between the optically sensitive orbital and the hosting medium, which become significant when the spectral feature is broad. An analytical expression for the temperature dependent decay rate by non-radiative processes is obtained by this way. Comparison with experiment on thermal quenching gives agreement within the experimental uncertainty. The solvent polarity, its protic or aprotic character, hydrogen bonds, proximity effects and presence of quenchers are expected to enter through the coupling constants of the corresponding energy terms.

  16. Orientifold Planar Equivalence: The Quenched Meson Spectrum

    CERN Document Server

    Lucini, Biagio; Patella, Agostino; Rago, Antonio

    2010-01-01

    A numerical study of Orientifold Planar Equivalence is performed in SU(N) Yang-Mills theories for N=2,3,4,6. Quenched meson masses are extracted in the antisymmetric, symmetric and adjoint representations for the pseudoscalar and vector channels. An extrapolation of the vector mass as a function of the pseudoscalar mass to the large-N limit shows that the numerical results agree within errors for the three theories, as predicted by Orientifold Planar Equivalence. As a byproduct of the extrapolation, the size of the corrections up to O(1/N^3) are evaluated. A crucial prerequisite for the extrapolation is the determination of an analytical relationship between the corrections in the symmetric and in the antisymmetric representations, order by order in a 1/N expansion.

  17. Quenched mesonic spectrum at large N

    CERN Document Server

    Del Debbio, Luigi; Patella, Agostino; Pica, Claudio

    2008-01-01

    We compute the masses of the $\\pi$ and of the $\\rho$ mesons in the quenched approximation on a lattice with fixed lattice spacing $a \\simeq 0.145 \\ \\mathrm{fm}$ for SU($N$) gauge theory with $N = 2,3,4,6$. We find that a simple linear expression in $1/N^2$ correctly captures the features of the lowest-lying meson states at those values of $N$. This enables us to extrapolate to $N = \\infty$ the behaviour of $m_{\\pi}$ as a function of the quark mass and of $m_{\\rho}$ as a function of $m_{\\pi}$. Our results for the latter agree within 5% with recent predictions obtained in the AdS/CFT framework.

  18. Electrochemical Degradation Characteristics of Refractory Organic Pollutants in Coking Wastewater on Multiwall Carbon Nanotube-Modified Electrode

    National Research Council Canada - National Science Library

    Wang, Yan; Sun, Shujing; Ding, Guifu; Wang, Hong

    2012-01-01

    ...), and chemical oxygen demand (COD) test, the electrochemical oxidation properties of refractory organic pollutants of coking wastewater using the MWCNT-ME and the IrSnSb/Ti electrode were analyzed...

  19. Torrefaction reduction of coke formation on catalysts used in esterification and cracking of biofuels from pyrolysed lignocellulosic feedstocks

    Energy Technology Data Exchange (ETDEWEB)

    Kastner, James R; Mani, Sudhagar; Hilten, Roger; Das, Keshav C

    2015-11-04

    A bio-oil production process involving torrefaction pretreatment, catalytic esterification, pyrolysis, and secondary catalytic processing significantly reduces yields of reactor char, catalyst coke, and catalyst tar relative to the best-case conditions using non-torrefied feedstock. The reduction in coke as a result of torrefaction was 28.5% relative to the respective control for slow pyrolysis bio-oil upgrading. In fast pyrolysis bio-oil processing, the greatest reduction in coke was 34.9%. Torrefaction at 275.degree. C. reduced levels of acid products including acetic acid and formic acid in the bio-oil, which reduced catalyst coking and increased catalyst effectiveness and aromatic hydrocarbon yields in the upgraded oils. The process of bio-oil generation further comprises a catalytic esterification of acids and aldehydes to generate such as ethyl levulinate from lignified biomass feedstock.

  20. Surface modification of graphite by coke coating for reduction of initial irreversible capacity in lithium secondary batteries

    Science.gov (United States)

    Yoon, Songhun; Kim, Hanjun; Oh, Seung M.

    Surface modification of graphite to reduce the irreversible capacity loss during the first charging period of graphite anodes is described. For the surface modification, artificial graphite (Lonza KS44) is dispersed in a tetrahydrofuran/acetone solution which contains coal tar pitch. The solvent is then evaporated. The loaded pitch component is converted to coke by a heat treatment at 1000°C in argon atmosphere. The resulting coke-coated graphite has a smaller surface area than that of the pristine one. The reduction of surface area, which is due to the coverage of pores of <10 nm by the coke component, causes a decrease in the irreversible capacity on the first cycle. The extent of electrolyte decomposition, gas evolution and surface film growth is also less with the coke-coated graphite electrode.

  1. Total Mercury Determination in Petroleum Green Coke and Oily Sludge Samples by Cold Vapor Atomic Fluorescence Spectrometry

    National Research Council Canada - National Science Library

    Camera, Adriana S; Maranhão, Tatiane A; Oliveira, Fernando J. S; Silva, Jessee S. A; Frescura, Vera L. A

    2015-01-01

    ...+ before the atomic vapor formation. Accuracy of the method was evaluated through certified reference material, for green coke, and comparison with cold vapor atomic absorption spectrometry (CV AAS), for oily sludge...

  2. 焦罐车旋转机构的改进%Improvement of Rotary Device of Coke Tank Truck

    Institute of Scientific and Technical Information of China (English)

    宫文龙

    2015-01-01

    This paper firstly analyzes the research status of the coke tank truck rotary device ,and then discusses the advatages and disadvantages of traditional coke tank truck rotary device .On this basis ,some measures to improve the rotary device are put for-ward ,and the superiority of the improved coke tank truck rotary device is discussed .This work may lay the basis for the design of large coke tank truck rotary device and other rotating mechanism .%对焦罐车旋转机构的现状进行了分析 ,探讨了传统焦罐车旋转机构的优劣 ,在此基础上对旋转机构进行了改进 ,改进后的焦罐车旋转机构可作为大型焦罐车旋转机构的设计依据.

  3. Stability and quench development study in small HTSC magnet

    NARCIS (Netherlands)

    Ilyin, Yu. A.; Vysotski, V.S.; Kiss, T.; Takeo, M.; Okamoto, H.; Irie, F.

    2001-01-01

    Stability and quench development in a HTSC magnet have been experimentally studied with the transport current in the magnet being below or above the “thermal quench current” level. The magnet was tested at both cryocooler cooling and liquid nitrogen cooling, with and without background magnetic fiel

  4. The quenched generating functional for hadronic weak interactions

    NARCIS (Netherlands)

    Pallante, E.

    1999-01-01

    The ultraviolet behaviour of the generating functional for hadronic weak interactions with |ΔS| = 1, 2 is investigated to one loop for a generic number of flavours and in the quenched approximation. New quenched chiral logarithms generated by the weak interactions can be accounted for via a redefin

  5. Stability and quench development study in small HTSC magnet

    NARCIS (Netherlands)

    Ilyin, Y.; Vysotski, V.S.; Kiss, T.; Takeo, M.; Okamoto, H.; Irie, F.

    2001-01-01

    Stability and quench development in a HTSC magnet have been experimentally studied with the transport current in the magnet being below or above the “thermal quench current” level. The magnet was tested at both cryocooler cooling and liquid nitrogen cooling, with and without background magnetic

  6. QUENCHING PROBLEMS OF DEGENERATE FUNCTIONAL REACTION-DIFFUSION EQUATION

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper is concerned with the quenching problem of a degenerate functional reaction-diffusion equation. The quenching problem and global existence of solution for the reaction-diffusion equation are derived and, some results of the positive steady state solutions for functional elliptic boundary value are also presented.

  7. Quenched transmission of light through ultrathin metal films

    DEFF Research Database (Denmark)

    Xiao, Sanshui; Mortensen, N. Asger

    2011-01-01

    We discuss optical properties of ultrathin metal films, with particular attention to the phenomenon of quenched transmission. Transmission of light through an optically ultrathin metal film with a thickness comparable to its skin depth is significant. We demonstrate the quenched transmission thro...

  8. Chiral and continuum extrapolation of partially quenched lattice results

    Energy Technology Data Exchange (ETDEWEB)

    C.R. Allton; W. Armour; D.B. Leinweber; A.W. Thomas; R.D. Young

    2005-04-01

    The vector meson mass is extracted from a large sample of partially quenched, two-flavor lattice QCD simulations. For the first time, discretization, finite-volume and partial quenching artifacts are treated in a unified chiral effective field theory analysis of the lattice simulation results.

  9. STUDY OF THE POSSIBILITY OF OBTAINING GAS TURBINE FUEL FROM THE PRODUCTS OF CATALYTIC CRACKING AND COKING,

    Science.gov (United States)

    52.5% of the cracked raw material. (2) For getting light, low-ash gasturbine fuels with traces of vanadium, the process of coking heavy petroleum...residues, should be accomplished with recirculation. (3) In contact coking of raw material with recirculation of the sulfurous pitch, tar and cracking residue, the yield of low-ash gasturbine fuel, amounted to 45, 56.2, and 64.4%.

  10. Occurrence and particle-size distributions of polycyclic aromatic hydrocarbons in the ambient air of coking plant.

    Science.gov (United States)

    Liu, Xiaofeng; Peng, Lin; Bai, Huiling; Mu, Ling; Song, Chongfang

    2014-06-01

    The purpose of this study was to characterize the occurrence and size distributions of ten species of polycyclic aromatic hydrocarbons (PAHs) in the ambient air of coking plants. Particulate-matter samples of four size fractions, including ≤2.1, 2.1-4.2, 4.2-10.2, and ≥10.2 μm, were collected using a Staplex234 cascade impactor during August 2009 at two coking plants in Shanxi, China. The PAHs were analyzed by a gas chromatograph equipped with a mass-selective detector. The concentrations of total particulate-matter PAHs were 1,412.7 and 2,241.1 ng/m(3) for plants I and II, and the distributions showed a peak within the 0.1-2.1 μm size range for plant I and the 0.1-4.2 μm for plant II. The size distributions of individual PAHs (except fluoranthene) exhibited a considerable peak within the 0.1-2.1 μm size range in coking plant I, which can be explained by the gas-particle partition mechanism. The ambient air of the coking plant was heavily polluted by PAHs associated with fine particles (≤2.1 μm), and benzo[b]fluoranthene made the largest contribution to total PAHs. The exposure levels of coking-plant workers to PAHs associated with fine particles were higher than to PAHs associated with coarse particles. Benzo[b]fluoranthene, benzo[a]pyrene, and dibenzo[a,h]anthracene should be the primary pollutants monitored in the coking plant. This research constitutes a significant contribution to assessing the exposure risk of coking-plant workers and providing basic data for PAH standards for ambient air in coking plants.

  11. Results of the simulation of gasification of the mexican petroleum coke from the refineries of Ciudad Madero and Cadereyta

    Directory of Open Access Journals (Sweden)

    G. Urquiza–Beltrán

    2008-04-01

    Full Text Available This paper evaluates in terms of energy the gasification of the petroleum coke from the refineries of Cd Madero and Cadereyta in Mexico. The energy evaluation of the synthetic gas (syngas focuses mainly on the chemical composition of the clean syngas (gasl and its energy characteristics: heating value, the energy power, the cold gas efficiency and the thermal efficiency of gasification. The results of the simulation indicate that the gasification of the petroleum coke from Cadereyta called CRC, produces a gasl with better performance and energy characteristics than those obtained when gasifying the coke of petroleum from Cd. Madero, called CRM. When the CRC is gasified, the rate of production of gasl obtained is of 2.07 kggasl/kgcoque, while the rate of production of gasl for the CRM is 1.89 kggasl/kgcoque. The HHV of the gasl of the CRC is 12 729.56 kJ/kggasl while for the CRM is 11 639.13 kJ/kggasl. The energy power of the gasl of the CRC is greater, with a difference of 25.87 GJ/h, with regard to the energy power of the gasl of the CRM. Under the specified conditions of operation, energy is generated ata rate of 26.46 MJ/kgcoque coke in the gasification of the CRC coke of petroleum, while when gasifying the CRM coke of petroleum 22.09 MJ/kgcoque are generated. Currently, the petroleum coke produced in the refinery of Madero is consumed in the power plants of Tamuín, San Luis Potosí, Mexico, while the petroleum coke produced by the refinery of Cadereyta is used in the cement industry.

  12. Reaction Mechanism for the Formation of Nitrogen Oxides (NO x ) During Coke Oxidation in Fluidized Catalytic Cracking Units

    KAUST Repository

    Chaparala, Sree Vidya

    2015-06-11

    Fluidized catalytic cracking (FCC) units in refineries process heavy feedstock obtained from crude oil distillation. While cracking feed, catalysts get deactivated due to coke deposition. During catalyst regeneration by burning coke in air, nitrogen oxides (NOx) are formed. The increase in nitrogen content in feed over time has resulted in increased NOx emissions. To predict NOx concentration in flue gas, a reliable model for FCC regenerators is needed that requires comprehensive understanding and accurate kinetics for NOx formation. Based on the nitrogen-containing functional groups on coke, model molecules are selected to study reactions between coke-bound nitrogen and O2 to form NO and NO2 using density functional theory. The reaction kinetics for the proposed pathways are evaluated using transition state theory. It is observed that the addition of O2 on coke is favored only when the free radical is present on the carbon atom instead of nitrogen atom. Thus, NOx formation during coke oxidation does not result from the direct attack by O2 on N atoms of coke, but from the transfer of an O atom to N from a neighboring site. The low activation energies required for NO formation indicate that it is more likely to form than NO2 during coke oxidation. The favorable pathways for NOx formation that can be used in FCC models are identified. Copyright © 2015 Taylor & Francis Group, LLC.

  13. Cyanides in a soil of a former coking plant site

    Energy Technology Data Exchange (ETDEWEB)

    Mansfeldt, T.; Gehrt, S.B. [Bochum Univ. (Germany). Geographisches Inst.; Friedl, J. [Technische Univ. Muenchen (Germany). Lehrstuhl fuer Bodenkunde

    1998-12-31

    Soils of former coking plant sites are frequently contaminated with cyanide, which mainly occurs as the pigment Berlin blue, Fe{sup III}{sub 4}[Fe{sup II}(CN){sub 6}]{sub 3}, and soluble iron cyanide complexes, Fe(CN){sub 6}{sup 3-/4-}. Berlin blue is only slightly soluble under acidic conditions. The cyanide mobility in a strongly acid soil (pH about 3) of such a site was studied by assessing the distribution of cyanides in the soil and sediment and by conducting batch experiments at different pH levels. The soil is based on a disposal layer (0-32 cm) overlying sandy loess (32-145 cm) overlying glaciofluvial sand (145-250 cm) overlying marlstone (250-500 cm). Highest cyanide concentrations were found in the disposal layer (62-2865 mg CN{sup -} kg{sup -1}), medium concentrations in the sandy loess (16-29 mg CN{sup -} kg{sup -1}), concentrations of about 100 mg CN{sup -} kg{sup -1} in the glaciofluvial sand and lowest concentrations in the marlstone (0.22-0.49 mg CN{sup -} kg{sup -1}). The surfaces of macropores, which occur in the sandy loess and finish in the glasicofluvial sand, are dark-blue dyed and have much higher cyanide concentrations than the surrounding bulk soil. Thus, the accumulation of cyanides in the sand layer may partly be the result of macropore flow. Batch experiments show a strong pH dependence of the solubility of cyanide in the soil as well as of Berlin blue which was found by Moessbauer spectroscopy to be the dominating or sole iron cyanide. The time necessary to transport the cyanides solely as hexacyanoferrate into the undisturbed horizons is estimated to 1000 yr. However, because Berlin blue is known to form colloids, we discuss the possibility of cyanide transport as colloid not requiring dissolution and reprecipitation. We postulate that colloidal Berlin blue transported by macropore flow is responsible for the high mobility of cyanides in this acid soil. (orig.) [Deutsch] Boeden ehemaliger Kokereistandorte sind haeufig mit Cyaniden

  14. Chiral Loops and Ghost States in the Quenched Scalar Propagator

    Energy Technology Data Exchange (ETDEWEB)

    W. Bardeen; A. Duncan; E. Eichten; N. Isgur; H. Thacker

    2001-06-01

    The scalar, isovector meson propagator is analyzed in quenched QCD, using the MQA pole-shifting ansatz to study the chiral limit. In addition to the expected short-range exponential falloff characteristic of a heavy scalar meson, the propagator also exhibits a longer-range, negative metric contribution which becomes pronounced for smaller quark masses. We show that this is a quenched chiral loop effect associated with the anomalous structure of the eta' propagator in quenched QCD. Both the time dependence and the quark mass dependence of this effect are well-described by a chiral loop diagram corresponding to an eta'-pi intermediate state, which is light and effectively of negative norm in the quenched approximation. The relevant parameters of the effective Lagrangian describing the scalar sector of the quenched theory are determined.

  15. Dynamics of Holographic Entanglement Entropy Following a Local Quench

    CERN Document Server

    Rangamani, Mukund; Vincart-Emard, Alexandre

    2015-01-01

    We discuss the behaviour of holographic entanglement entropy following a local quench in 2+1 dimensional strongly coupled CFTs. The entanglement generated by the quench propagates along an emergent light-cone, reminiscent of the Lieb-Robinson light-cone propagation of correlations in non-relativistic systems. We find the the speed of propagation is bounded from below by the entanglement tsunami velocity obtained earlier for global quenches in holographic systems, and from above by the speed of light. The former is realized for sufficiently broad quenches, while the latter pertains for well localized quenches. The non-universal behavior in the intermediate regime appears to stem from finite-size effects. We also note that the entanglement entropy of subsystems reverts to the equilibrium value exponentially fast, in contrast to a much slower equilibration seen in certain spin models.

  16. Thermal and electrochemical studies of carbons for Li-ion batteries. 1. Thermal analysis of petroleum and pitch cokes

    Science.gov (United States)

    Jiang, W.; Tran, T.; Song, X.; Kinoshita, K.

    Thermal analyses involving simultaneous thermal gravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study the air oxidation of petroleum (fluid and needle cokes) and coal-tar pitch cokes. The intent of this study is to understand the relationship between the structure of carbonaceous materials and their thermal oxidation behavior in air (Part 1). A correlation between the thermal oxidative properties of cokes and their electrochemical Li-intercalation performance is discussed in the following paper (Part 2). The carbon samples were heat-treated at temperatures up to 2800°C, and three thermal parameters were determined — ignition temperature ( Ti), temperature maximum ( Tm) in the DTA curves, and the temperature at which 15% carbon weight loss was attained ( T15). The measurements showed trends that are consistent with prior reports that the active sites on the surface and not the total surface area (TSA) are responsible for the thermal behavior of the carbons. Because of the difference in the graphitizability of petroleum and pitch cokes that was obtained by heat treatment, variations in the thermal parameters were observed. Needle cokes are the most easily graphitized and this is reflected in the higher values of the thermal parameters compared to the fluid and pitch cokes.

  17. Effects of habitat light conditions on the excitation quenching pathways in desiccating Haberlea rhodopensis leaves: an Intelligent FluoroSensor study.

    Science.gov (United States)

    Solti, Ádám; Lenk, Sándor; Mihailova, Gergana; Mayer, Péter; Barócsi, Attila; Georgieva, Katya

    2014-01-05

    Resurrection plants can survive dehydration to air-dry state, thus they are excellent models of understanding drought and dehydration tolerance mechanisms. Haberlea rhodopensis, a chlorophyll-retaining resurrection plant, can survive desiccation to relative water content below 10%. Leaves, detached from plants of sun and shade habitats, were moderately (∼50%) dehydrated in darkness. During desiccation, chlorophyll a fluorescence was detected by the recently innovated wireless Intelligent FluoroSensor (IFS) chlorophyll fluorometer, working with three different detectors: a pulse-amplitude-modulated (PAM) broadband channel and two channels to measure non-modulated red and far-red fluorescence. No change in area-based chlorophyll content of leaves was observed. The maximal quantum efficiency of photosystem II decreased gradually in both shade and sun leaves. Shade leaves could not increase antennae-based quenching, thus inactivated photosystem II took part in quenching of excess irradiation. Sun leaves seemed to be pre-adapted to quench excess light as they established an intensive increase in antennae-based non-photochemical quenching parallel to desiccation. The higher far-red to red antennae-based quenching may sign light-harvesting complex reorganization. Thus, compared to PAM, IFS chlorophyll fluorometer has additional benefits including (i) parallel estimation of changes in the Chl content and (ii) prediction of underlying processes of excitation energy quenching.

  18. ITER Side Correction Coil Quench model and analysis

    Science.gov (United States)

    Nicollet, S.; Bessette, D.; Ciazynski, D.; Duchateau, J. L.; Gauthier, F.; Lacroix, B.

    2016-12-01

    Previous thermohydraulic studies performed for the ITER TF, CS and PF magnet systems have brought some important information on the detection and consequences of a quench as a function of the initial conditions (deposited energy, heated length). Even if the temperature margin of the Correction Coils is high, their behavior during a quench should also be studied since a quench is likely to be triggered by potential anomalies in joints, ground fault on the instrumentation wires, etc. A model has been developed with the SuperMagnet Code (Bagnasco et al., 2010) for a Side Correction Coil (SCC2) with four pancakes cooled in parallel, each of them represented by a Thea module (with the proper Cable In Conduit Conductor characteristics). All the other coils of the PF cooling loop are hydraulically connected in parallel (top/bottom correction coils and six Poloidal Field Coils) are modeled by Flower modules with equivalent hydraulics properties. The model and the analysis results are presented for five quench initiation cases with/without fast discharge: two quenches initiated by a heat input to the innermost turn of one pancake (case 1 and case 2) and two other quenches initiated at the innermost turns of four pancakes (case 3 and case 4). In the 5th case, the quench is initiated at the middle turn of one pancake. The impact on the cooling circuit, e.g. the exceedance of the opening pressure of the quench relief valves, is detailed in case of an undetected quench (i.e. no discharge of the magnet). Particular attention is also paid to a possible secondary quench detection system based on measured thermohydraulic signals (pressure, temperature and/or helium mass flow rate). The maximum cable temperature achieved in case of a fast current discharge (primary detection by voltage) is compared to the design hot spot criterion of 150 K, which includes the contribution of helium and jacket.

  19. Combustion characteristics of Daqing oil shale and oil shale semi-cokes

    Institute of Scientific and Technical Information of China (English)

    MIAO Zhen-yong; WU Guo-guang; LI Ping; ZHAO Na; WANG Pan-cheng; MENG Xian-liang

    2009-01-01

    Thermo-gravimetric-analysis (TGA) was used to analyze the combustion characteristics of an oil shale and semi-cokes prepared from it. The effect of prior pyrolysis and TGA heating rate on the combustion process was studied. Prior pyrolysis affects the initial temperature of mass loss and the ignition temperature. The ignition temperature increases as the volatile content of the sample decreases. TG/DTG curves obtained at different heating rates show that heating rate has little effect on ignition temperature. But the peak of combustion shifts to higher temperatures as the heating rate is increased. The Coats-Redfern integration method was employed to find the combustion-reaction kinetic parameters for the burning of oil shale and oil shale semi-coke.

  20. Development and Application of High Quality Silica Brick for Coke Ovens

    Institute of Scientific and Technical Information of China (English)

    WANGHongmei; XIAOChangyu

    1998-01-01

    As coke oven becoming larger,silica brick for coke oven is required to be of high uqality,Luoyang Refractories(Grop)Co.Ltd.(LRCO) has re-searched the mineralizer which contains Ca2+,R+,Al3+,F-,emphatically and proposed the principle of composite mineralizer basd on the properties of raw materials used .High performance silia brick which is characterized by low thermal expansion rate,good high temperature properties,residual quartz<0.5%,true density 2.31,and high bulk density silica brick for carbonization room with apparent porosity 13% ,bulk density l.96 g/cm3 have been developed and produced successfully by LR-CO.The quality of the bricks has reached the inter-national advenced level.

  1. Investigating the temperature field on doors, frames and armor plate of large capacity coke ovens

    Energy Technology Data Exchange (ETDEWEB)

    Shashov, D.V.; Shustorovich, V.M.; Komolov, V.G.; Zhazhin, S.N.

    1985-06-01

    Experimental studies were carried out at the Altaiskii and Avdeevskii coking plants to determine the temperature field on the frames, doors and armor plating of coking batteries with a capacity of 41.6 m/sup 3/. It was established that for normal operation the temperature on metal parts of the combustion chambers remained stable. However, when gas is burned, the metal is subjected to rapid heating to temperatures exceeding those under normal operation. After the flame is extinguished, cooling is characterized by an accelerated temperature drop along the ribs and the temperature on the door and frame at the upper cross beam is higher than at other levels of the combustion chamber. Several recommendations on eliminating these temperature effects are made, e.g. using material with stable mechanical properties for doors, frames and armor plate. 4 references.

  2. Study on CO2 gasification reactivity and physical characteristics of biomass, petroleum coke and coal chars.

    Science.gov (United States)

    Huo, Wei; Zhou, Zhijie; Chen, Xueli; Dai, Zhenghua; Yu, Guangsuo

    2014-05-01

    Gasification reactivities of six different carbonaceous material chars with CO2 were determined by a Thermogravimetric Analyzer (TGA). Gasification reactivities of biomass chars are higher than those of coke and coal chars. In addition, physical structures and chemical components of these chars were systematically tested. It is found that the crystalline structure is an important factor to evaluate gasification reactivities of different chars and the crystalline structures of biomass chars are less order than those of coke and coal chars. Moreover, initial gasification rates of these chars were measured at high temperatures and with relatively large particle sizes. The method of calculating the effectiveness factor η was used to quantify the effect of pore diffusion on gasification. The results show that differences in pore diffusion effects among gasification with various chars are prominent and can be attributed to different intrinsic gasification reactivities and physical characteristics of different chars. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Reducibility mill scale industrial waste via coke breeze at 850-950ºC

    Directory of Open Access Journals (Sweden)

    Gaballah N.M.

    2015-01-01

    Full Text Available Mill scale is a very attractive industrial waste due to its elevated iron content (about = 69.33% Fe besides being suiTab. for direct recycling to the blast furnace via sintering plant. In this paper the characteristics of raw materials and the briquettes produced from this mill scale were studied by different methods of analyses. The produced briquettes were reduced with different amounts of coke breeze at varying temperatures, and the reduction kinetics was determined. The activation energy of this reaction ≈ 61.5 kJ/mole for reduction of mill scale with coke breeze in the form of briquettes with 2% molasses where the chemical reaction interface model is applicable.

  4. Functionalization of Petroleum Coke-Derived Carbon for Synergistically Enhanced Capacitive Performance

    Science.gov (United States)

    Zhang, Yan; Li, Xuejin; Huang, Jufeng; Xing, Wei; Yan, Zifeng

    2016-03-01

    Petroleum coke is a valuable and potential source for clean energy storage if it could be modified legitimately and facilely. In the present study, porous carbon with high surface area and abundant oxygen-containing groups was prepared from petroleum coke by chemical activation and modification processes. The as-prepared carbon exhibits a high surface area (1129 m2 · g-1) and stable micrographic structure. It presents a high specific capacitance and excellent rate performance in KOH electrolyte. Even at an ultrahigh current density of 50 A · g-1, the specific capacitance of the prepared carbon can still reach up to an unprecedented value of 261 F · g-1 with a superhigh retention rate of 81 %. In addition, the energy density of this material in aqueous electrolyte can be as high as 13.9 Wh · kg-1. The high energy density and excellent rate performance ensure its prosperous application in high-power energy storage system.

  5. Effects of three industrial wastes on kinetic characteristics of petroleum coke-CO{sub 2} gasification

    Energy Technology Data Exchange (ETDEWEB)

    Zou Jian-hui; Zhou Zhi-jie; Dai Zheng-hua; Liu Hai-feng; Wang Fu-chen; Yu Zun-hong [East China University of Science & Technology, Shanghai (China). Institute of Clean Coal Technology

    2008-07-01

    Three industrial wastes including black liquor from papermaking industry, coal slag, and sludge were used as catalysts for petroleum coke-CO{sub 2} gasification. The gasification kinetics characteristics with and without a catalyst were studied using a pressurized thermo gravimetric analyzer (TGA). It is shown that gasification rate increases with increasing conversion and then decreases after reaching a maximal rate for noncatalytic gasification, while decreases in whole course for catalytic gasification. The proposed normal distribution function model describes well the kinetic curve for both noncatalytic and catalytic gasification. The calculated activation energy of noncatalytic petroleum coke-CO{sub 2} gasification is 197.7 kJ/mol, which is in accordance with the reported data. The activities of three catalysts are contributed to the content of metal species. The black liquor in papermaking industry rich in Na species has the best activity, and its gasification rate is six times as that of noncatalytic gasification. 19 refs., 11 figs., 4 tabs.

  6. Thermal and hydraulic effects of coke deposit in hydrocarbon pyrolysis process

    OpenAIRE

    2012-01-01

    International audience; Fuel pyrolysis can be of benefit for regenerative cooling techniques due to its endothermic effect in ensuring the thermal resistance of hypersonic vehicles and structures. Among pyrolysis species production, there is that of coke formation. A numerical code is used in this paper to investigate the related phenomena, based on two experiments using Titanium (Ti) and Stainless Steel (SS) reactors, which present different pyrolysis rates under similar operating conditions...

  7. Determination of reactivity parameters of model carbons, cokes and flame-chars

    DEFF Research Database (Denmark)

    Sørensen, Lasse Holst; Gjernes, Erik; Jessen, Thomas

    1996-01-01

    Reactivity profiles are defined and measured with thermogravimetry for a dense metallurgical Longyear coke, a polymer-derived porous active carbon, Carboxen 1000, and three flame-chars, Illinois #6, Pittsburgh #8 and New Mexico Blue #1. For each sample it is found that the reactivity profile can ...... reactivity measure is used to rank fuels with very different structural profiles, at varying levels of burnout, temperature and oxygen partial pressure. Keyword: TGA,Reactivity,Coal...

  8. Selection, follow-up, and analysis in the Coke Oven Study.

    Science.gov (United States)

    Rockette, H E; Redmond, C K

    1985-05-01

    The current standard for exposure to coke oven emissions sets a permissible exposure of 150 micrograms benzene-soluble fraction of total particulate matter/m3. The major epidemiologic study that formed the basis for this standard including a review of the evidence of a dose-response relationship between exposure to coal tar pitch volatiles and lung cancer is reviewed. Particular attention was given to the selection of the cohort, follow-up procedures, and the evolution of the analysis.

  9. [Enhanced bioremediation of coking plant soils contaminated with polycyclic aromatic hydrocarbons].

    Science.gov (United States)

    Lu, Xiao-Xia; Li, Xiu-Li; Ma, Jie; Wu, Shu-Ke; Chen, Chao-Qi; Wu, Wei

    2011-03-01

    Soil samples contaminated with polycyclic aromatic hydrocarbons (PAHs) were collected from Beijing Coking Plant. The purposes were to isolate PAHs degrading bacteria from the soils, determine their appropriate living condition, enrich them and apply them in the enhanced bioremediation of the contaminated soils. Using each of the 16 USEPA priority PAHs as the sole carbon source, PAHs degrading bacteria were isolated using the method of plate streaking and identified by genetic analysis. In total seven species of PAHs degrading bacteria were obtained. When mixed, these bacteria could degrade the 16 (2-6 cyclic) PAHs studied at appropriate concentrations. In the liquid medium, when the total concentration of the 16 PAHs (sigma PAH16) was 17 microg/mL, single bacteria could grow well and degrade the PAHs. However, when sigma PAH16 was 166 microg/mL, the growth and activity of either single PAHs degrading bacteria or a mixture of the seven PAHs degrading bacteria were inhibited. Aiming at the contaminated soils from Beijing coking plant, five treatments were performed, i.e., control (C), addition of nutrient (N), addition of nutrient and PAHs degrading bacteria (N + B), addition of nutrient and surfactant (N +S), addition of nutrient and PAHs degrading bacteria and surfactant (N + B + S). After five weeks of experiment, compared to the C treatment, the mean removal rate of the 16 PAHs in the N + B treatment was increased 32%, and the mean removal rate of the 16 PAHs in the N + B + S treatment was increased 46% (the mean removal rate of the 10 4-6 cyclic PAHs was increased 52%). The addition of PAHs degrading bacteria and surfactant could significantly enhance the degradation of PAHs in the soils. This study provides evidence for the enhanced bioremediation of PAHs contaminated soil for Beijing coking plant and other coking plants.

  10. CO2 recycling by means of reforming of coke oven gas for methanol production

    Directory of Open Access Journals (Sweden)

    J. M. Bermúdez

    2013-01-01

    Full Text Available The steelmaking industry is the largest energyconsuming manufacturing sector. As a consequence of this, the CO2 emissions from this sector account for about 5-7 % of the total anthropogenic CO2 emissions. For this reason, increasing efforts are being made to find solutions that might help diminish these emissions and increase energy efficiency. A better management of the coke oven gas (COG surplus is one of the proposed solutions...

  11. Dynamics study on effect of temperature to Nitrous nitrification reaction of coking wastewater

    Institute of Scientific and Technical Information of China (English)

    SHAN Ming-jun; ZHANG Hai-ling; LU Yan-li

    2007-01-01

    Dynamic effects of NO2 - - N accumulation were discussed owing to temperature. In different temperature, a series ofvmax and Ks were found considering the relation between the temperature and rate of ammonia nitrogen transforming into NO2 - - N. The kinetics models, which reflected the conditions of ammonia nitrogen transforming into NO2 - - N in the treatment process of the coking wastewater, were built up. The characteristic coefficient temperature was determined according to Arrhenius.

  12. Quench Protection and Magnet Supply Requirements for the MICEFocusingand Coupling Magnets

    Energy Technology Data Exchange (ETDEWEB)

    Green, Michael A.; Witte, Holger

    2005-06-08

    This report discusses the quench protection and power supply requirements of the MICE superconducting magnets. A section of the report discusses the quench process and how to calculate the peak voltages and hotspot temperature that result from a magnet quench. A section of the report discusses conventional quench protection methods. Thermal quench back from the magnet mandrel is also discussed. Selected quench protection methods that result in safe quenching of the MICE focusing and coupling magnets are discussed. The coupling of the MICE magnets with the other magnets in the MICE is described. The consequences of this coupling on magnet charging and quenching are discussed. Calculations of the quenching of a magnet due quench back from circulating currents induced in the magnet mandrel due to quenching of an adjacent magnet are discussed. The conclusion of this report describes how the MICE magnet channel will react when one or magnets in that channel are quenched.

  13. 40 CFR 1065.370 - CLD CO2 and H2O quench verification.

    Science.gov (United States)

    2010-07-01

    ... analyzer uses quench compensation algorithms that utilize H2O and/or CO2 measurement instruments, evaluate quench with these instruments active and evaluate quench with the compensation algorithms applied....

  14. Comparisons of four quench methods for high temperature Syngas-Exergy Analyses

    Science.gov (United States)

    Liu, Y. H.; Chen, W.; Che, D. F.; Cao, Z. D.

    2010-03-01

    Entrained flow slagging gasifiers have been found in many applications, one of which is IGCC. The quench of high temperature syngas from first stage of entrained flow slagging gasifiers is of great importance for the availability of gasifiers, and it influences the economical running of utilization system. Four kinds of quench methods including water quench, gas quench, radiant quench and chemical quench, are investigated by Gibbs free energy minimization and exergy analyses. The exergy distributions of the streams into and out of each quench system are obtained. The results show that exergy loss of water quench is the biggest, and the exergy loss of chemical quench is the least and can be neglectable. The exergy losses of the other two quench methods are comparable, which are only 1/3 smaller than that of water quench. Chemical quench not only features in lower oxygen consumption as well as a higher cold gas efficiency, but also has high exergy efficiency.

  15. Effect of oxygen potential on sulphur dioxide activation of oil sands fluid coke and characteristics of activated coke in mercury adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Morris, E.A.; Jia, C.Q. [Toronto Univ., ON (Canada). Dept. of Chemical Engineering and Applied Chemistry; Tong, S. [Wuhan Univ. of Science and Technology, Wuhan, Hobei (China). Dept. of Chemical Engineering

    2007-07-01

    A sulphur-impregnated activated carbon (SIAC) technology was modified for use in copper smelters in order to mitigate mercury and sulphur dioxide (SO{sub 2}) emissions. Elemental sulphur was captured as a co-product. The study examined the feasibility of reducing levels of SO{sub 2} using fluid coke in the copper smelter flue. SIAC properties were optimized in order to capture vapour phase mercury. Raw fluid coke samples were used to measure SO{sub 2} flow rates. Gas composition was varied to mimic concentrations found during normal operation of copper converters. Gas chromatography was used to analyze reactions products and to prove the hypothesis that mercury capacity is influenced by the oxygen potential of the activation gas due to changes in surface sulphur types developed from reduced sulphur species. Results of the study showed that oxygen levels at 5 per cent did not play a significant role in pore development. It was concluded that increased residence times contributed to reductions in SO{sub 2} and elemental S yields. 13 refs., 1 tab., 7 figs.

  16. Coupling thermogravimetric and acoustic emission measurements: its application to study the inhibition of catalytic coke deposition

    Energy Technology Data Exchange (ETDEWEB)

    Ropital, Francois; Dascotte, Philippe; Marchand, Pierre [Institut Francais du Petrole, 1 Avenue Bois Preau, 92952 Rueil-Malmaison (France); Faure, Thierry; Lenain, Jean-Claude; Proust, Alain [Euro Physical Acoustics, 27 Rue Magellan, 94373 Sucy-en-Brie Cedex (France)

    2004-07-01

    In order to improve the knowledge on the high temperature behaviour of metallic materials, the coupling of several in situ physical analysis methods is a promising way. For this purpose a thermogravimetric balance has been equipped with a specific acoustic emission device in order to continuously measure the mass variation of the corrosion sample and the acoustic emission transient under experimental conditions of temperature and gas phase compositions that are representative of the industrial environments. The catalytic coke deposition condition that is a major problem for the refinery and petrochemical industries, has been studied with such a device. The carbon deposition on reactor walls can induce localised disruption in the process such as heat-transfer reduction and pressure drops. To prevent these perturbations, proper selections of the metallurgical or internal coating compositions of the equipment, or the injection of accurate amount of inhibitors have to be decided. The feasibility of the coupling at high temperature of thermogravimetric and acoustic emission has been demonstrated. This new technique has been applied to study the inhibition of the catalytic coke deposition on pure iron by sulphur additives in the temperature range of 650 deg. C and under different mixed atmospheres of hydrocarbon and hydrogen contents. Good correlation has been obtained between the coking rates measured by thermogravimetric measurements and the intensities of the acoustic emission parameters. (authors)

  17. Electrochemical behavior of surface-modified petroleum cokes in propylene carbonate containing solvents

    Energy Technology Data Exchange (ETDEWEB)

    Naga, Kazuhisa; Nakajima, Tsuyoshi; Aimura, Shinya; Ohzawa, Yoshimi [Department of Applied Chemistry, Aichi Institute of Technology, Yakusa, Toyota 470-0392 (Japan); Zemva, Boris; Mazej, Zoran [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Groult, Henri [Universite Pierre et Marie Curie, LI2C Laboratoire Electrochimie, 4 Place Jussieu 75252 Paris 05 (France); Yoshida, Akira [Faculty of Engineering, Musashi Institute of Technology, 1-28-1 Tamazutsumi, Setagaya-ku, Tokyo 158-8557 (Japan)

    2007-05-01

    Surface modification of petroleum coke (PC) and those heat-treated at 1860, 2300 and 2800 C (PC1860, PC2300 and PC2800) has been performed by F{sub 2}, ClF{sub 3} and NF{sub 3} to improve their charge/discharge characteristics in propylene carbonate containing solvents. Surface fluorination by F{sub 2} increased surface disorder of PC1860, PC2300 and PC2800, leading to increase in their first coulombic efficiencies in 1 mol dm{sup -3} LiClO{sub 4}-ethylene carbonate (EC)/diethyl carbonate (DEC)/propylene carbonate (PPC) (1:1:1 in volume) solution. First coulombic efficiencies were the largest in fluorinated PC1860 with the highest surface disorder. However, surface modification by ClF{sub 3} and NF{sub 3} did not increase surface disorder of petroleum cokes, being not as effective as the fluorination with F{sub 2} to increase first coulombic efficiencies of petroleum cokes. The reactions of ClF{sub 3} and NF{sub 3} with carbon materials are radical reactions while the reaction with F{sub 2} is an electrophilic reaction yielding fluorinated layers with high disorder. Surface modification using F{sub 2}, ClF{sub 3} and NF{sub 3} also increased first charge capacities of PC and PC1860. (author)

  18. Use of shungite rock in place of some coke for ferroalloy smelting

    Energy Technology Data Exchange (ETDEWEB)

    Strakhov, V.M.; Maksimov, Yu.S.

    1986-07-01

    A study is described of the feasibility of using Class III shungite (20-35% carbon content) for ferroalloy production. Heat treatment analysis of samples showed that separation of CO began at 1300 C and reached a maximum at 1550-1650 C. Trial production of 25% ferrosilicon showed that coke carbon could be replaced with shungite carbon, resulting in a charge composition of 20-5 mm coke, 70-25 mm quartzite and 80-20 mm shungite rock. Use of 3% and 6% shungite in charges reduced coke consumption by 10.6-14.8%, quartzite consumption by 3.5-6.9% and electricity consumption by 0.5-2.7%. Overall cost reductions were 5.8% in first period (3% shungite) and 1.8% in second period (6% shungite). It is concluded that production of FS25 and FS18 ferroalloys at ferroalloy plants in the south would require about 29 kt of shungite rock and lead to savings of over 400,000 rubles. 11 references.

  19. Ionic Liquid Catalyst Used in Deep Desulfuration of the Coking Benzene for Producing Sulfurless Benzene

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xia-Ping; WANG Yan-Liang; MENG Fan-Wei; FAN Xing-Ming; QIN Song-Bo

    2008-01-01

    For the widening need of benzene used in organic synthesis, ionic liquid catalyst was prepared to study the process of deep desulfuration in the coking benzene. The result shows that the effect of de-thiophene by the ionic liquid catalyst (N-methyl imidazolium hydrogen sulfate [Hmim][HSO4]) is related to its acid function value.Hammett indicator was used to determine the acid function value H0 of the ionic liquid. It can be concluded that while the acid function value is in the range from -4 to -12, the ionic liquid catalyst can make the concentration certain acid quantity and strength, the ionic liquid catalyst helps to form alkyl thiophene through Friedel-Crafts reaction, which differs from the character of benzene and it is absolutely necessary for the separation and refinement of benzene. But overabundant quantity and higher acid value of [Hmim][HSO4] are more suitable for the side copolymerization of benzene, thiophene and alkene, thereby affecting repeated use of the ionic liquid catalyst([Hmim][HSO4]). In our research, thiophene derivant produced by desulfurization in the coking benzene was used as the polymer to provide the passing channel of the charges. The ionic liquid composition in poor performance after repeated use was made to prepare conductive material (resisting to static electricity) as an "electron-receiving" and "electron-giving" doping agent. The result shows that thiophene derivant after desulfuration in the coking benzene can be used to prepare doping conductive materials.

  20. Mercury oxidation and adsorption characteristics of potassium permanganate modified lignite semi-coke

    Institute of Scientific and Technical Information of China (English)

    Huawei Zhang; Jitao Chen; Peng Liang; Li Wang

    2012-01-01

    The adsorption characteristics of virgin and potassium permanganate modified lignite semi-coke (SC) for gaseous Hg0 were investigated in an attempt to produce more effective and lower price adsorbents for the control of elemental mercury emission.Brunauer-Emmett-Teller (BET) measurements,X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to analyze the surface physical and chemical properties of SC,Mn-SC and Mn-H-SC before and after mercury adsorption.The results indicated that potassium permanganate modification had significant influence on the properties of semi-coke,such as the specific surface area,pore structure and surface chemical functional groups.The mercury adsorption efficiency of modified semi-coke was lower than that of SC at low temperature,but much higher at high temperature.Amorphous Mn7+,Mn6+ and Mn4+ on the surface of Mn-SC and Mn-H-SC were the active sites for oxidation and adsorption of gaseous Hg0,which oxidized the elemental mercury into Hg2+ and captured it.Thermal treatment reduced the average oxidation degree of Mnx+ on the surface of Mn-SC from 3.80 to 3.46.However,due to the formation of amorphous MnOx,the surface oxidation active sites for gaseous Hg0 increased,which gave Mn-H-SC higher mercury adsorption efficiency than that of Mn-SC at high temperature.

  1. Mercury oxidation and adsorption characteristics of potassium permanganate modified lignite semi-coke.

    Science.gov (United States)

    Zhang, Huawei; Chen, Jitao; Liang, Peng; Wang, Li

    2012-01-01

    The adsorption characteristics of virgin and potassium permanganate modified lignite semi-coke (SC) for gaseous Hg0 were investigated in an attempt to produce more effective and lower price adsorbents for the control of elemental mercury emission. Brunauer-Emmett-Teller (BET) measurements, X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to analyze the surface physical and chemical properties of SC, Mn-SC and Mn-H-SC before and after mercury adsorption. The results indicated that potassium permanganate modification had significant influence on the properties of semi-coke, such as the specific surface area, pore structure and surface chemical functional groups. The mercury adsorption efficiency of modified semi-coke was lower than that of SC at low temperature, but much higher at high temperature. Amorphous Mn7+, Mn6+ and Mn4+ on the surface of Mn-SC and Mn-H-SC were the active sites for oxidation and adsorption of gaseous Hg0, which oxidized the elemental mercury into Hg2+ and captured it. Thermal treatment reduced the average oxidation degree of Mn(x+) on the surface of Mn-SC from 3.80 to 3.46. However, due to the formation of amorphous MnOx, the surface oxidation active sites for gaseous Hg0 increased, which gave Mn-H-SC higher mercury adsorption efficiency than that of Mn-SC at high temperature.

  2. Biological removal of antiandrogenic activity in gray wastewater and coking wastewater by membrane reactor process.

    Science.gov (United States)

    Ma, Dehua; Chen, Lujun; Liu, Cong; Bao, Chenjun; Liu, Rui

    2015-07-01

    A recombinant human androgen receptor yeast assay was applied to investigate the occurrence of antiandrogens as well as the mechanism for their removal during gray wastewater and coking wastewater treatment. The membrane reactor (MBR) system for gray wastewater treatment could remove 88.0% of antiandrogenic activity exerted by weakly polar extracts and 97.3% of that by moderately strong polar extracts, but only 32.5% of that contributed by strong polar extracts. Biodegradation by microorganisms in the MBR contributed to 95.9% of the total removal. After the treatment, the concentration of antiandrogenic activity in the effluent was still 1.05 μg flutamide equivalence (FEQ)/L, 36.2% of which was due to strong polar extracts. In the anaerobic reactor, anoxic reactor, and membrane reactor system for coking wastewater treatment, the antiandrogenic activity of raw coking wastewater was 78.6 mg FEQ/L, and the effluent of the treatment system had only 0.34 mg FEQ/L. The antiandrogenic activity mainly existed in the medium strong polar and strong polar extracts. Biodegradation by microorganisms contributed to at least 89.2% of the total antiandrogenic activity removal in the system. Biodegradation was the main removal mechanism of antiandrogenic activity in both the wastewater treatment systems. Copyright © 2015. Published by Elsevier B.V.

  3. Effect of petroleum coke expanding by perchloric acid on the performance of the resulted activated carbon

    Science.gov (United States)

    Deng, Mei-Gen; Wang, Ren-Qing

    2014-10-01

    Petroleum coke (PC) was expanded by using KMnO4 as oxidant and HClO4 as intercalator so as to decrease the amount of KOH needed for the successive activation. Activated carbon (AC) was prepared by activation of the expanded PC (EPC) at KOH/coke mass ratio of 3:1 (denoted as EAC-3). As a comparison, AC was also made by activation of PC at KOH/coke mass ratio of 3:1, 4:1 and 5:1 (denoted as AC-3, AC-4 and AC-5). Influence of expanding modification on the structure and performance of PC and AC was investigated. The results revealed that the expanding treatment increased the interplanar distance of PC microcrystalline from 0.344 to 0.362 nm and decreased the microcrystalline thickness from 2.34 to 1.57 nm. The specific surface area of EAC-3 and AC-5 was 3461 and 3291 m2ṡg-1, respectively. The average pore size of EAC-3 was 2.19 nm, which is 0.11 nm larger than that of AC-5. At a scan rate of 0.5 mVṡs-1, EAC-3 and AC-5 achieved a specific gravimetric capacitance of 486 and 429 Fṡg-1, respectively. Supercapacitor based on EAC-3 possessed lower resistance and better power performance.

  4. Beneficiation of an Indian non-coking coal by column flotation

    Institute of Scientific and Technical Information of China (English)

    N.Vasumathi; T.V.Vijaya Kumar; S.Ratchambigai; S.Subba Rao; S.Prabhakar; G.Bhaskar Raju

    2016-01-01

    Beneficiation of non-coking coal is gaining ground in India.It not only reduces the volume of inert content to be transported to the power plant and also lowers the wear in the boiler houses.For special applications such as the fuel for integrated gasification combined cycle plant (IGCC),the ash content in the coal should preferably be below 15 %.Indian coals are characterized by high inter-grown ash content mainly due to ‘drift origin’ of Gondwana formation in Permian age.This warrants fine grinding of non-coking coal in order to liberate the ash forming minerals from coal macerals.A noncoking coal sample of vitrinite type from India was ground to 44 tm (d80) and subjected to column flotation to improve its quality.The non-coking coal analyzing 34.6 % ash,26.2 % volatile matter,1.3 % moisture and 37.9 % fixed carbon could be upgraded to a concentrate/froth of 14.83 % ash at 72.18 % yield by optimizing collector and frother dosages and flotation column operating parameters,namely,froth depth,superficial feed velocity and superficial air velocity.The concentrate produced by this process is suitable as fuel for IGCC in coal-to-electricity route.

  5. Oxygen-containing coke species in zeolite-catalyzed conversion of methanol to hydrocarbons

    KAUST Repository

    Liu, Zhaohui

    2016-10-06

    Zeolites are the most commonly used catalysts for methanol-to-hydrocarbon (MTH) conversion. Here, we identified two oxygen-containing compounds as coke species in zeolite catalysts after MTH reactions. We investigated the possible influences of the oxygen-containing compounds on coke formation, catalyst deactivation, product selectivity, and the induction period of the MTH reaction through a series of controlled experiments in which one of the identified compounds (2,3-dimethyl-2-cyclopenten-1-one) was co-fed with methanol over a zeolite H-ZSM-5 catalyst. Our results allow us to infer that once produced, the oxygen-containing compounds block the Brønsted acid sites by strong chemisorption and their rapid conversion to aromatics expedites the formation of coke and thus the deactivation of the catalyst. A minor effect of the production of such compounds during the MTH reaction is that the aromatic-based catalytic cycle can be slightly promoted to give higher selectivity to ethylene.

  6. Occupational Exposure to Polycyclic Aromatic Hydrocarbons in Polish Coke Plant Workers.

    Science.gov (United States)

    Zając, Joanna; Gomółka, Ewa; Maziarz, Barbara; Szot, Wojciech

    2016-11-01

    Assessment of occupational exposure to polycyclic aromatic hydrocarbons (PAHs) is an urgent and important task to prevent workers' illnesses. 1-Hydroxypyrene is one of the most commonly used biomarkers. The presented study assessed exposure to PAHs molecules among 619 individuals, men working in coke plant. Average number of years spent on working posts in exposition to PAHs was 31.5 years with standard deviation = 5.3. About 35% were smokers with 14.7 cigarettes per day. For each individual, 1-hydroxypyrene concentration in urine samples was measured. Urine 1-hydroxypyrene concentration correlated with air PAHs concentration. Difference between smokers and non-smokers was statistically significant. The median value for post-shift samples was 1.3 µg g(-1) and for pre-shift sample concentration reached 0.3 µg g(-1) Maximal assessed concentration was 7.6 µg g(-1) among pre-shift samples and 27.8 µg g(-1) among post-shift samples. The most exposed working posts were coke oven workers and coal derivatives production workers. Results obtained in presented study are relatively low in comparison to other countries or other Polish results but for further improvement a regular measurement of any PAHs' biomarker should be included to standard periodic health examinations for coke plant workers. © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

  7. The effect of treatment stages on the coking wastewater hazardous compounds and their toxicity.

    Science.gov (United States)

    Wei, Xiao-xue; Zhang, Zi-yang; Fan, Qing-lan; Yuan, Xiao-ying; Guo, Dong-sheng

    2012-11-15

    This study investigated the change of hazardous materials in coking wastewater at different treatment stages (anaerobic, anaerobic/aerobic, anaerobic/aerobic/photo degradation, anaerobic/aerobic/ozone oxidation treatment) and the effects of them on the development of maize embryos and the activity of amylase and protease in maize seeds. Moreover the interaction of refractory organic matters in the wastewater at different treatment stages with amylase and protease also were determined in vitro. The results show that the biodegradable and the refractory organic compounds in the wastewater both can affect maize embryo development (germination inhibition rate is 19.3% for biodegradable organic compounds). As the treatment stage preceding, the inhibition effect of coking wastewater on the development of the maize embryo (for germination inhibition rates change from 49.3% to 24.6%) and on enzymatic activity (inhibition rates change from 63.9% to 22.4% for amylase) decreases gradually, but the photo-degradation treatment to anaerobic/aerobic effluent can increase its toxicity. The changes in the ability of the refractory organic compounds to bind with enzyme proteins, combined with the analysis of the organic components by GC/MS, show that in the process of coking wastewater treatment no new toxic chemicals were produced.

  8. Adsorption of organic pollutants from coking and papermaking wastewaters by bottom ash

    Energy Technology Data Exchange (ETDEWEB)

    Sun Weiling [Department of Environmental Engineering, Peking University, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871 (China)], E-mail: sunweiling@iee.pku.edu.cn; Qu Yanzhi; Yu Qing; Ni Jinren [Department of Environmental Engineering, Peking University, Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871 (China)

    2008-06-15

    Bottom ash, a power plant waste, was used to remove the organic pollutants in coking wastewater and papermaking wastewater. Particular attention was paid on the effect of bottom ash particle size and dosage on the removal of chemical oxygen demand (COD). UV-vis spectra, fluorescence excitation-emission matrix (FEEM) spectra, Fourier transform infrared (FTIR) spectra, and scanning electron microscopic (SEM) photographs were investigated to characterize the wastewaters and bottom ash. The results show that the COD removal efficiencies increase with decreasing particle sizes of bottom ash, and the COD removal efficiency for coking wastewater is much higher than that for papermaking wastewater due to its high percentage of particle organic carbon (POC). Different trends of COD removal efficiency with bottom ash dosage are also observed for coking and papermaking wastewaters because of their various POC concentrations. Significant variations are observed in the FEEM spectra of wastewaters after treatment by bottom ash. New excitation-emission peaks are found in FEEM spectra, and the fluorescence intensities of the peaks decrease. A new transmittance band in the region of 1400-1420 cm{sup -1} is observed in FTIR spectra of bottom ash after adsorption. The SEM photographs reveal that the surface of bottom ash particles varies evidently after adsorption.

  9. A perturbative framework for jet quenching

    Science.gov (United States)

    Zapp, Korinna C.; Krauss, Frank; Wiedemann, Urs A.

    2013-03-01

    We present a conceptually new framework for describing jet evolution in the dense medium produced in ultra-relativistic nucleus-nucleus collisions using perturbative QCD and its implementation into the Monte Carlo event generator Jewel. The rescattering of hard partons in the medium is modelled by infrared continued pQCD matrix elements supplemented with parton showers. The latter approximate higher order real-emission matrix elements and thus generate medium-induced gluon emissions. The interplay between different emissions is governed by their formation times. The destructive interference between subsequent scattering processes, the non-Abelian version of the Landau-Pomeranchuk-Migdal effect, is also taken into account. In this way the complete radiation pattern is consistently treated in a uniform way. Results obtained within this minimal and theoretically well constrained framework are compared with a variety of experimental data susceptible to jet-quenching effects at both RHIC and the LHC. Overall, a good agreement between data and simulation is found. This new framework also allows to identify and quantify the dominant uncertainties in the simulation, and we show some relevant examples for this.

  10. Quenched Heavy-Light Decay Constants

    CERN Document Server

    Baxter, R M; Bowler, K C; Collins, S; Henty, D S; Kenway, R D; Richards, D G; Shanahan, H P; Simone, J N; Simpson, A D; Wilkes, B E; Ewing, A K; Lellouch, L P; Sachrajda, Christopher T C; Wittig, H

    1994-01-01

    We present results for heavy-light decay constants, using both propagating quarks and the static approximation, in O(a)-improved, quenched lattice QCD. At beta=6.2 on a 24^3x48 lattice we find f_D=185 +4-3(stat)+42-7(syst) MeV, f_B=160 +6-6 +53-19 MeV, f_{D_s}/f_D=1.18 +2-2 and f_{B_s}/f_B=1.22 +4-3, in good agreement with earlier studies. From the static theory we obtain f_B^stat=253 +16-15 +105-14 MeV. We also present results from a simulation at beta=6.0 on a 16^3x48 lattice, which are consistent with those at beta=6.2. In order to study the effects of improvement, we present a direct comparison of the results using both the Wilson and the improved action at beta=6.0.

  11. Nonequilibrium States of a Quenched Bose Gas

    Science.gov (United States)

    Ling, Hong; Kain, Ben

    2014-05-01

    Yin and Radzihovsky [Phys. Rev. A 88, 063611 (2014)] recently developed a self-consistent extension of a Bogoliubov theory, in which the condensate number density, nc, is treated as a mean field that changes with time in order to analyze a JILA experiment by Makotyn et al. [Nature Physics doi:10.1038/nphys2850 (2014)] on a 85Rb Bose gas following a deep quench to a large scattering length. We apply this theory to construct a set of closed equations that highlight the role of dnc/dt, which is to induce an effective interaction between quasiparticles. We show analytically that such a system supports a steady state characterized by a constant condensate density and a steady but periodically changing momentum distribution, whose time average is described exactly by the generalized Gibbs ensemble. We discuss how the dnc/dt-induced effective interaction, which cannot be ignored on the grounds of the adiabatic approximation for modes near the gapless Goldstone mode, can affect experimentally measurable quantities such as Tan's contact. This work is supported in part by the US Army Research Office under Grant No. W911NF-10-1-0096 and in part by the US National Science Foundation under Grant No. PHY11-25915.

  12. Quenching parameter in a holographic thermal QCD

    CERN Document Server

    Patra, Binoy Krishna

    2016-01-01

    We have calculated the quenching parameter, $\\hat{q}$ in a model-independent way using the gauge-gravity duality. In earlier calculations, the geometry in the gravity side at finite temperature was usually taken as the pure AdS blackhole metric for which the dual gauge theory becomes conformally invariant unlike QCD. Therefore we use a metric which incorporates the fundamental quarks by embedding the coincident D7 branes in the Klebanov-Tseytlin background and a finite temperature is switched on by inserting a black hole into the background, known as OKS-BH metric. Further inclusion of an additional UV cap to the metric prepares the dual gauge theory to run similar to thermal QCD. Moreover $\\hat{q}$ is usually defined in the literature from the Glauber-model perturbative QCD evaluation of the Wilson loop, which has no reasons to hold if the coupling is large and is thus against the main idea of gauge-gravity duality. Thus we use an appropriate definition of $\\hat{q}$: $\\hat{q} L^- = 1/L^2$, where $L$ is the s...

  13. Quorum Quenching Agents: Resources for Antivirulence Therapy

    Directory of Open Access Journals (Sweden)

    Kaihao Tang

    2014-05-01

    Full Text Available The continuing emergence of antibiotic-resistant pathogens is a concern to human health and highlights the urgent need for the development of alternative therapeutic strategies. Quorum sensing (QS regulates virulence in many bacterial pathogens, and thus, is a promising target for antivirulence therapy which may inhibit virulence instead of cell growth and division. This means that there is little selective pressure for the evolution of resistance. Many natural quorum quenching (QQ agents have been identified. Moreover, it has been shown that many microorganisms are capable of producing small molecular QS inhibitors and/or macromolecular QQ enzymes, which could be regarded as a strategy for bacteria to gain benefits in competitive environments. More than 30 species of marine QQ bacteria have been identified thus far, but only a few of them have been intensively studied. Recent studies indicate that an enormous number of QQ microorganisms are undiscovered in the highly diverse marine environments, and these marine microorganism-derived QQ agents may be valuable resources for antivirulence therapy.

  14. Molecular insights into Zeaxanthin-dependent quenching in higher plants

    Science.gov (United States)

    Xu, Pengqi; Tian, Lijin; Kloz, Miroslav; Croce, Roberta

    2015-01-01

    Photosynthetic organisms protect themselves from high-light stress by dissipating excess absorbed energy as heat in a process called non-photochemical quenching (NPQ). Zeaxanthin is essential for the full development of NPQ, but its role remains debated. The main discussion revolves around two points: where does zeaxanthin bind and does it quench? To answer these questions we have followed the zeaxanthin-dependent quenching from leaves to individual complexes, including supercomplexes. We show that small amounts of zeaxanthin are associated with the complexes, but in contrast to what is generally believed, zeaxanthin binding per se does not cause conformational changes in the complexes and does not induce quenching, not even at low pH. We show that in NPQ conditions zeaxanthin does not exchange for violaxanthin in the internal binding sites of the antennas but is located at the periphery of the complexes. These results together with the observation that the zeaxanthin-dependent quenching is active in isolated membranes, but not in functional supercomplexes, suggests that zeaxanthin is acting in between the complexes, helping to create/participating in a variety of quenching sites. This can explain why none of the antennas appears to be essential for NPQ and the multiple quenching mechanisms that have been observed in plants. PMID:26323786

  15. Quench simulations for superconducting elements in the LHC accelerator

    CERN Document Server

    Sonnemann, F

    2000-01-01

    The design of he protection system for he superconducting elements in an accel- erator such as the Large Hadron Collider (LHC),now under construction at CERN, requires a detailed understanding of the hermo-hydraulic and electrodynamic pro- cesses during a quench.A numerical program (SPQR -Simulation Program for Quench Research)has been developed o evaluate temperature and voltage dis ri- butions during a quench as a func ion of space and ime.The quench process is simulated by approximating the heat balance equation with the finite di fference method in presence of variable cooling and powering conditions.The simulation predicts quench propagation along a superconducting cable,forced quenching with heaters,impact of eddy curren s induced by a magnetic field change,and heat trans- fer hrough an insulation layer in o helium,an adjacen conductor or other material. The simulation studies allowed a better understanding of experimental quench data and were used for determining the adequ...

  16. Systematic study of particle quenching in organic scintillators

    Energy Technology Data Exchange (ETDEWEB)

    Santiago, L.M.; Bagán, H. [Department of Analytical Chemistry of the University of Barcelona, Diagonal 645, E-08028 Barcelona (Spain); Tarancón, A., E-mail: alex.tarancon@ub.edu [Department of Analytical Chemistry of the University of Barcelona, Diagonal 645, E-08028 Barcelona (Spain); Rauret, G.; Garcia, J.F. [Department of Analytical Chemistry of the University of Barcelona, Diagonal 645, E-08028 Barcelona (Spain)

    2013-01-11

    Among the different factors that affect measurements by organic scintillators, the majority of attention has been focused on those related to the scintillator (i.e., ionization, chemical, color and optical quenching), and less attention has been paid to the loss of energy before the particle (i.e., alpha or beta) arrives at the scintillator (i.e., particle quenching). This study evaluates the effect of particle quenching in different scintillation methods (i.e., using two plastic scintillation microspheres (PSm1 and PSm2), liquid scintillator and gel scintillator) by measuring solutions that contain increasing concentrations of NaCl, BaCl{sub 2} and glycerin. The results show the importance of particle quenching in PSm measurements because detection efficiency decreases with increasing concentrations of the quenching component, although the spectrum position and external standard parameter remain constant. The results have shown evidence of particle quenching, although at a lower magnitude, in the liquid scintillation or gel scintillation measurements. Moreover, the use of two PSm with different diameters and salty compound that alters the equilibrium of the liquid and gel emulsions also exemplified the importance of the transmission of optical photons through different scintillation media (i.e., optical quenching). Improvement and deterioration of the optical conditions on the scintillation media is manifested as a movement of the spectrum to higher and lower energies, respectively. The results obtained with PSm were confirmed by Monte Carlo simulation.

  17. The Mass Dependence of Dwarf Satellite Galaxy Quenching

    CERN Document Server

    Slater, Colin T

    2014-01-01

    We combine observations of the Local Group with data from the NASA-Sloan Atlas to show the variation in the quenched fraction of satellite galaxies from low mass dwarf spheroidals and dwarf irregulars to more massive dwarfs similar to the Magellanic clouds. While almost all of the low mass ($M_\\star \\lesssim 10^7$ $M_\\odot$) dwarfs are quenched, at higher masses the quenched fraction decreases to approximately 40-50%. This change in the quenched fraction is large, and suggests a sudden change in the effectiveness of quenching that correlates with satellite mass. We combine this observation with models of satellite infall and ram pressure stripping to show that the low mass satellites must quench within 1-2 Gyr of pericenter passage to maintain a high quenched fraction, but that many more massive dwarfs must continue to form stars today even though they likely fell in to their host >5 Gyr ago. We also characterize how the susceptibility of dwarfs to ram pressure must vary as a function of mass if it is to acco...

  18. Temperature Control of 5.5 m Tamping Coke Oven%浅谈5.5米捣固焦炉的温度控制

    Institute of Scientific and Technical Information of China (English)

    赵广磊

    2016-01-01

    The maturity condition of the coke near the machine side and the coke side is poor due to the temperature differ⁃ence between the machine side and the coke side. Throttle orifice plates were adopted in the horizontal tube grid to change the the gas flow distribution in the coke side, the temperatures in the machine side and the coke side were changed and the quality of the machine⁃side coke and the coke side coke were improved. Fire⁃fall management was combined with standard temperature to rectify standard temperature required for coke maturity.%由于捣固焦炉机焦侧温差较小,且焦侧高于机侧,导致机焦侧焦炭成熟情况不佳,通过在横排管中采用节流孔板的方法,改变机焦侧煤气流量分布,从而改变机焦侧温度,提高了机焦侧焦炭质量,并通过采用火落管理与标准温度相结合,修正焦炭成熟所需的标准温度。

  19. Quench-induced trapping of magnetic flux in annular

    DEFF Research Database (Denmark)

    Aaroe, M.; Monaco, R.; Rivers, R.;

    2008-01-01

    over 4 orders of magnitude. After the quench the result of the spontaneous production of topological defects, trapped fluxons, is unambiguously observed as zero-field steps in the DC I-V characteristic of the junction. A power-law scaling behavior of trapping probability versus quench rate is found...... with a critical exponent of 0.5 (within experimental error). The main experimental challenges are to generate many identical quenches with accurate cooling rate, to automate data analysis and acquisition, and to suppress external magnetic fields and noise by passive magnetic shielding and compensation....

  20. Dynamical quenching with non-local alpha and downward pumping

    CERN Document Server

    Brandenburg, A; Käpylä, P J

    2014-01-01

    In light of new results, the one-dimensional mean-field dynamo model of Brandenburg & Kapyla (2007) with dynamical quenching and a nonlocal Babcock-Leighton alpha effect is re-examined for the solar dynamo. We extend the one-dimensional model to include the effects of turbulent downward pumping (Kitchatinov & Olemskoy 2011), and to combine dynamical quenching with shear. We use both the conventional dynamical quenching model of Kleeorin & Ruzmaikin (1982) and the alternate one of Hubbard & Brandenburg (2011), and confirm that with varying levels of non-locality in the alpha effect, and possibly shear as well, the saturation field strength can be independent of the magnetic Reynolds number.

  1. Quench Dynamics in Confined 1+1-Dimensional Systems

    CERN Document Server

    Engelhardt, Dalit

    2015-01-01

    We present a scheme for investigating the response of confined 1+1-dimensional systems to a quantum quench and consider the extent to which a system whose post-quench dynamics are near-integrable may be analyzed by an application of boundary CFT techniques. As the main example we present a model of a split-momentum quench in a finite 1D geometry, a setup analogous to that of the experiment of Kinoshita, Wenger, and Weiss [Nature 440, 900 (2006)]. We analytically derive the form of the expected momentum distributions and describe how such information may be used to assess the extent of integrability breaking in realistic systems.

  2. Development of phased array and tofd simultaneous inspection system for coke drum

    Energy Technology Data Exchange (ETDEWEB)

    Oka, M. [Sumitomo Heavy Industries, Ltd., Toyo Works, Quality Assurance Dept., Ehime (Japan); Kawashima, K. [S.H.I. Examination and Inspection, Ltd., Inspection and Engineering Dept., Ehime (Japan)

    2004-07-01

    Our current AUT (automatic ultrasonic testing) system is ''phased array linear scan and dual TOFD (time of fight diffraction) simultaneous inspection system'' which has been applied to the pre-service inspection at shop in lieu of radiography as per ASME Code case 2235-4 and the in-service inspection at user's turnaround stage for the circumferential and longitudinal weld joints of shell courses of coke drum. The coke drum is 13-30 feet in diameter and 80-100 feet in height. The base material of coke drum is either C-1/2Mo steel, 1Cr-1/2Mo steel, 1.25Cr-1/2Mo steel, or 2.25Cr-1Mo steel with type 410S or 405 stainless steel cladding material, and clad restoration weld material is either Inconel 82, Inconel 625 or same material as the cladding material (13Cr stainless steel). It is too difficult to detect the flaws in the clad restoration weld by the conventional manual UT and/or TOFD, but phased array can clearly detect them. In order to improve the capability to detect and size the low cycle fatigue crack caused in the clad restoration weld and its heat affected zone due to the cyclic operation of coke drum ''phased array sector scan'' has been adopted. This paper reports the verification test results of ''dual phased array sector scan'' (the simultaneous scanning by a pair of phased array probes placed equally for the centerline of weld joint) in comparison with the verification test results of TOFD, and introduces the characteristic of our current AUT system. In consideration with the verification test results in this paper, we would like to propose that ''dual phased array sector scan and dual TOFD simultaneous inspection system'' (the simultaneous inspection by four (4) kinds of AUT) will be applied to the in-service inspection for the coke drum and other important reactors overlaid inside by stainless steel or inconel at the oil refineries and/or petrochemical plants. (orig.)

  3. Energy Efficient Textile Drying

    OpenAIRE

    Brunzell, Lena

    2006-01-01

    Traditionally, textiles were dried outdoors with the wind and the sun enhancing the drying process. Tumble dryers offer a fast and convenient way of drying textiles independent of weather conditions. Tumble dryers, however, consume large amounts of electrical energy. Over 4 million tumble dryers are sold each year in Europe and a considerable amount of energy is used for drying of clothes. Increasing energy costs and the awareness about environmental problems related to a large energy use has...

  4. Effect of Extracted Compositions of Liquefaction Residue on the Structure and Properties of the Formed-coke

    Directory of Open Access Journals (Sweden)

    Song Yong-hui

    2016-01-01

    Full Text Available The purpose of this paper is to study the effect of extracted compositions of the de-ash liquefaction residue (D-DCLR on pyrolysis products yields, compressive strength and composition of the formed-coke, which was prepared by co-pyrolysis of the low metamorphic pulverized coal and D-DCLR. The scanning electron microscope (SEM and the Fourier Transform Infrared (FT-IR were used to characterize the morphology and functional group of the formed-coke, respectively. The results showed that the extracted compositions of D-DCLR were heavy oil (HS, asphaltene (A, pre-asphaltene (PA and tetrahydrofuran isolusion (THFIS, whose contents were 5.10%, 40.90%, 14.4%, 39.60%, respectively. During the pyrolysis process, HS was the main source of tar, and HS, A as well as PA were conducive to improve gas yields. The THFIS helped to improve the yield of the formed-coke up to 89.5%, corresponding to the compressive strength was only 147.7N/ball for the coke. A and PA were the key factors affecting the compressive strength and surface structure of the formed-coke. The compressive strength of coke could be up to 728.0N/ball with adding D-DCLR, which reduced by 50% after the removal of A and PA. The FT-IR analysis showed that the types of surface functional groups of the formed-coke were remained the same after co-pyrolysis, but the absorption peak intensity of each functional group was changed.

  5. Quenching parameter in a holographic thermal QCD

    Science.gov (United States)

    Patra, Binoy Krishna; Arya, Bhaskar

    2017-01-01

    We have calculated the quenching parameter, q ˆ in a model-independent way using the gauge-gravity duality. In earlier calculations, the geometry in the gravity side at finite temperature was usually taken as the pure AdS black hole metric for which the dual gauge theory becomes conformally invariant unlike QCD. Therefore we use a metric which incorporates the fundamental quarks by embedding the coincident D7 branes in the Klebanov-Tseytlin background and a finite temperature is switched on by inserting a black hole into the background, known as OKS-BH metric. Further inclusion of an additional UV cap to the metric prepares the dual gauge theory to run similar to thermal QCD. Moreover q ˆ is usually defined in the literature from the Glauber model perturbative QCD evaluation of the Wilson loop, which has no reasons to hold if the coupling is large and is thus against the main idea of gauge-gravity duality. Thus we use an appropriate definition of q ˆ : q ˆ L- = 1 /L2, where L is the separation for which the Wilson loop is equal to some specific value. The above two refinements cause q ˆ to vary with the temperature as T4 always and to depend linearly on the light-cone time L- with an additional (1 /L-) correction term in the short-distance limit whereas in the long-distance limit, q ˆ depends only linearly on L- with no correction term. These observations agree with other holographic calculations directly or indirectly.

  6. Quenching simulation of steel grinding balls

    Directory of Open Access Journals (Sweden)

    Zapata-Hernández, Oscar

    2015-09-01

    Full Text Available The phase transformations of high carbon steel during quenching and equalizing were modelled using commercial computer packages based on the finite element method and the kinetic transformation of steel. The model was used to predict the temperature and microstructural changes taking place within balls of two different sizes that are used for grinding mineral ores. A good correlation between the temperatures measured by inserted thermocouples and those predicted by the model was obtained after modifying the thermal conductivity of the steel within the temperature domain at which mixed phases are present. The phase transformations predicted were confirmed by metallographic analyses.Las transformaciones de fase en aceros de alto carbono durante su temple y un posterior periodo de estabilización fueron modelizadas por medio del uso de paquetes computacionales basados en el método del elemento finito y de la transformación cinética de los aceros. El modelo se usó para predecir los cambios de temperatura y microestructura que se presentan en bolas de dos diferentes tamaños empleadas en estaciones de molienda de minerales. Se encontró una buena correlación entre las temperaturas medidas mediante la inserción de termopares y aquellas predichas por el modelo una vez que se modificó la conductividad térmica del acero en el intervalo mixto de fases. La predicción de las transformaciones de fase se confirmó a través del análisis metalográfico.

  7. Responses to desiccation stress in bryophytes and an important role of dithiothreitol-insensitive non-photochemical quenching against photoinhibition in dehydrated states.

    Science.gov (United States)

    Nabe, Hayase; Funabiki, Ryoko; Kashino, Yasuhiro; Koike, Hiroyuki; Satoh, Kazuhiko

    2007-11-01

    The effects of air drying and hypertonic treatments in the dark on seven bryophytes, which had grown under different water environments, were studied. All the desiccation-tolerant species tested lost most of their PSII photochemical activity when photosynthetic electron transport was inhibited by air drying, while, in all the sensitive species, the PSII photochemical activity remained at a high level even when photosynthesis was totally inhibited. The PSI reaction center remained active under drying conditions in both sensitive and tolerant species, but the activity became non-detectable in the light only in tolerant species due to deactivation of the cyclic electron flow around PSI and of the back reaction in PSI. Light-induced non-photochemical quenching (NPQ) was found to be induced not only by the xanthophyll cycle but also by a DeltapH-induced, dithiothreitol-insensitive mechanism in both the desiccation-tolerant and -intolerant bryophytes. Both mechanisms are thought to have an important role in protecting desiccation-tolerant species from photoinhibition under drying conditions. Fluorescence emission spectra at 77K showed that dehydration-induced quenching of PSII fluorescence was observed only in tolerant species and was due to neither state 1-state 2 transition nor detachment of light-harvesting chlorophyll protein complexes from PSII core complexes. The presence of dehydration-induced quenching of PSI fluorescence was also suggested.

  8. Spontaneous quenches of a high temperature superconducting pancake coil

    Energy Technology Data Exchange (ETDEWEB)

    Lue, J.W.; Lubell, M.S. [Oak Ridge National Lab., TN (United States); Aized, D.; Campbell, J.M.; Schwall, R.E. [American Superconductor Corp., Westborough, MA (United States)

    1995-09-01

    A double-pancake coil made of Bi-2223/Ag high temperature superconducting (HTS) tape was constructed with an embedded heater and graded conductors to study the stability and quench propagation in HTS coils. The experiments were performed with liquid nitrogen and gaseous helium cooling in temperatures ranging from 5 to 77 K. The coil was very stable, and no ``normal`` zone was sustained or propagated with local pulsed heating. However, spontaneous quenches of the cod were experienced. This was found to be the result of having the coil current higher than that of the lower I{sub c} sections of the coil for a long time. This quench process took minutes to develop--much longer than would be expected in a low temperature superconducting coil. The quench behaved more like a spreading and continuous heating of an increasingly larger partially resistive section of the coil than like a sequential ``normal`` front propagation.

  9. Carbonated aqueous media for quench heat treatment of steels

    Science.gov (United States)

    Nayak, U. Vignesh; Rao, K. M. Pranesh; Pai, M. Ashwin; Prabhu, K. Narayan

    2016-09-01

    Distilled water and polyalkylene glycol (PAG)-based aqueous quenchants of 5 and 10 vol.% with and without carbonation were prepared and used as heat transfer media during immersion quenching. Cooling curves were recorded during quenching of an inconel 600 cylindrical probe instrumented with multiple thermocouples. It was observed that the vapor stage duration was prolonged and the wetting front ascended uniformly for quenching with carbonated media. The cooling data were analyzed by determining the critical cooling parameters and by estimating the spatially dependent probe/quenchant interfacial heat flux transients. The study showed significantly reduced values of heat transfer rate for carbonated quenchants compared to quenchants without carbonation. Further, the reduction was more pronounced in the case of PAG-based carbonated quenchants than carbonated distilled water. The results also showed the dependence of heat transfer characteristics of the carbonated media on polymer concentration. The effect of quench uniformity on the microstructure of the material was assessed.

  10. Positronium quenching in liquid and solid octanol and benzene

    DEFF Research Database (Denmark)

    Shantarovich, V.P.; Mogensen, O.E.; Goldanskii, V.I.

    1970-01-01

    The lifetimes of orthopositronium in several solutions in liquid and solid octanol and benzene have been measured. The Ps-quenching constant was found to be two to thirty times higher in the solid than in the liquid phase....

  11. Plasma quench production of titanium from titanium tetrachloride

    Energy Technology Data Exchange (ETDEWEB)

    Sears, J.W.

    1994-10-01

    This project, Plasma Quench Production of Titanium from Titanium Tetrachloride, centers on developing a technique for rapidly quenching the high temperature metal species and preventing back reactions with the halide. The quenching technique chosen uses the temperature drop produced in a converging/diverging supersonic nozzle. The rapid quench provided by this nozzle prevents the back reaction of the halide and metal. The nature of the process produces nanosized particles (10 to 100 nm). The powders are collected by cyclone separators, the hydrogen flared, and the acid scrubbed. Aluminum and titanium powders have been produced in the laboratory-scale device at 1 gram per hour. Efforts to date to scale up this process have not been successful.

  12. Quenching effects in Cu-Al-Mn shape memory alloy

    Energy Technology Data Exchange (ETDEWEB)

    Obrado, E.; Manosa, L.; Planes, A. [Barcelona Univ. (Spain). Dept. d' Estructura i Constituents de la Materia; Romero, R.; Somoza, A. [IFIMAT, Universidad Nacional del Centro de la Provincia de Buenos Aires, Pinto 399, 7000 Tandil, and Comision de Investigaciones Cientificas de la Provincia de Buenos Aires, Buenos Aires (Argentina)

    1999-12-15

    In this paper the effect of quenching from different temperatures (T{sub q}) in a Cu-Al-Mn alloy is studied. This alloy system, which displays an L2{sub 1} ordered structure, transforms martensitically at an intermediate temperature T{sub M}, and undergoes a spin freezing process at a lower temperature T{sub f}. Positron annihilation measurements have shown that after the quench, an excess of vacancies is retained in the system, depending on T{sub q}. In addition, both T{sub M} and T{sub f} have been found to be sensitive to T{sub q}. This has been attributed to frozen-in disorder induced by the quench. Experimental results have been interpreted in terms of the growth of magnetic clusters, quenched-in vacancies and atomic disorder. (orig.)

  13. Simulating Zeno physics by a quantum quench with superconducting circuits

    Science.gov (United States)

    Tong, Qing-Jun; An, Jun-Hong; Kwek, L. C.; Luo, Hong-Gang; Oh, C. H.

    2014-06-01

    Studying out-of-equilibrium physics in quantum systems under quantum quench is of vast experimental and theoretical interest. Using periodic quantum quenches, we present an experimentally accessible scheme to simulate the quantum Zeno and anti-Zeno effects in an open quantum system of a single superconducting qubit interacting with an array of transmission line resonators. The scheme is based on the following two observations: First, compared with conventional systems, the short-time nonexponential decay in our superconducting circuit system is readily observed; and second, a quench-off process mimics an ideal projective measurement when its time duration is sufficiently long. Our results show the active role of quantum quench in quantum simulation and control.

  14. Anthracene Fluorescence Quenching by a Tetrakis (Ketocarboxamide Cavitand

    Directory of Open Access Journals (Sweden)

    Tibor Zoltan Janosi

    2014-01-01

    Full Text Available Quenching of both fluorescence lifetime and fluorescence intensity of anthracene was investigated in the presence of a newly derived tetrakis (ketocarboxamide cavitand at various concentrations. Time-correlated single photon counting method was applied for the lifetime measurements. A clear correlation between the fluorescence lifetime of anthracene as a function of cavitand concentration in dimethylformamide solution was observed. The bimolecular collisional quenching constant was derived from the decrease of lifetime. Fluorescence intensity was measured in the emission wavelength region around 400 nm as a result of excitation at 280 nm. Effective quenching was observed in the presence of the cavitand. The obtained Stern-Volmer plot displayed upward curvature. The results did not follow even extended Stern-Volmer behavior, often used to describe deviations from static bimolecular quenching. To explain our results we adopted the Smoluchowski model and obtained a reasonable estimate for the molecular radius of the cavitand in solution.

  15. Measurement of cell volume changes by fluorescence self-quenching

    DEFF Research Database (Denmark)

    Hamann, Steffen; Kiilgaard, J.F.; Litman, Thomas

    2002-01-01

    At high concentrations, certain fluorophores undergo self-quenching, i.e., fluorescence intensity decreases with increasing fluorophore concentration. Accordingly, the self-quenching properties can be used for measuring water volume changes in lipid vesicles. In cells, quantitative determination...... of water transport using fluorescence self-quenching has been complicated by the requirement of relatively high (mM) and often toxic loading concentrations. Here we report a simple method that uses low (muM) loading concentrations of calcein-acetoxymethyl ester (calcein-AM) to obtain intracellular...... concentrations of the fluorophore calcein suitable for measurement of changes in cell water volume by self-quenching. The relationship between calcein fluorescence intensity, when excited at 490 nm (its excitation maximum), and calcein concentration was investigated in vitro and in various cultured cell types...

  16. Quenched moderate deviations principle for random walk in random environment

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    We derive a quenched moderate deviations principle for the one-dimensional nearest random walk in random environment,where the environment is assumed to be stationary and ergodic.The approach is based on hitting time decomposition.

  17. Reliability analysis for the quench detection in the LHC machine

    CERN Document Server

    Denz, R; Vergara-Fernández, A

    2002-01-01

    The Large Hadron Collider (LHC) will incorporate a large amount of superconducting elements that require protection in case of a quench. Key elements in the quench protection system are the electronic quench detectors. Their reliability will have an important impact on the down time as well as on the operational cost of the collider. The expected rates of both false and missed quenches have been computed for several redundant detection schemes. The developed model takes account of the maintainability of the system to optimise the frequency of foreseen checks, and evaluate their influence on the performance of different detection topologies. Seen the uncertainty of the failure rate of the components combined with the LHC tunnel environment, the study has been completed with a sensitivity analysis of the results. The chosen detection scheme and the maintainability strategy for each detector family are given.

  18. Numerical Methods for Safeguarding the Performance of the Quenching Process

    Institute of Scientific and Technical Information of China (English)

    I. FELDE; T. RETI; S. Segerberg; J. Bodin; G. S. Sarmiento; G. E. Totten; J. GU

    2004-01-01

    A new numerical technique for testing and evaluation of quenching media and quenching systems is outlined. The measured time-temperature samples as a result of cooling curve test are analyzed by the new software developed, in order to characterize quantitatively the quenchants. The method applied is based on Fourier analysis. Examples for evaluation and comparison of cooling performance of quenchants are presented the applicability of the computational technique.

  19. Satellite quenching, Galaxy inner density and the halo environment

    Science.gov (United States)

    Woo, Joanna; Carollo, C. M.; Faber, S. M.; Dekel, Avishai; Tacchella, Sandro

    2017-01-01

    Using the Sloan Digital Sky Survey, we adopt the specific star formation rate (sSFR)-Σ*,1kpc diagram as a diagnostic tool to understand quenching in different environments. sSFR is the specific star formation rate and Σ*,1kpc is the stellar surface density in the inner kpc. Although both the host halo mass and group-centric distance affect the satellite population, we find that these can be characterized by a single number, the quenched fraction, such that key features of the sSFR-Σ*,1kpc diagram vary smoothly with this proxy for the `environment'. Particularly, the sSFR of star-forming galaxies decreases smoothly with this quenched fraction, the sSFR of satellites being 0.1 dex lower than in the field. Furthermore, Σ*,1kpc of the transition galaxies (i.e. the `green valley' or GV) decreases smoothly with the environment by as much as 0.2 dex for M* = 109.75-10 from the field, and decreasing for satellites in larger haloes and at smaller radial distances within same-mass haloes. We interpret this shift as indicating the relative importance of today's field quenching track versus the cluster quenching track. These environmental effects in the sSFR-Σ*,1kpc diagram are most significant in our lowest mass range (9.75 < log M*/M⊙ < 10). One feature that is shared between all environments is that at a given M*, quenched galaxies have about 0.2-0.3 dex higher Σ*,1kpc than the star-forming population. These results indicate that either Σ*,1kpc increases (subsequent to satellite quenching), or Σ*,1kpc for individual galaxies remains unchanged, but the original M* or the time of quenching is significantly different from those now in the GV.

  20. Oxygen quenching in LAB based liquid scintillator and nitrogen bubbling

    CERN Document Server

    Hua-Lin, Xiao

    2009-01-01

    Oxygen quenching effect in Linear Alkl Benzne (LAB) based liquid scintillator (LAB+3g/L POPOP+ 15 mg Bis--MSB) was studied by measuring the light yield as the function of nitrogen bubbling time. it shows that the light yield of fully purged liquid scintillator would increase of nearly 11% in room temperature and room atmosphere pressure. A simple model of nitrogen bubbling was built to describe the relationship between relative light yield (oxygen quenching factor) and bubbling time.