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Sample records for cooled slagging coal

  1. NONEQUILIBRIUM SULFUR CAPTURE & RETENTION IN AN AIR COOLED SLAGGING COAL COMBUSTOR

    Energy Technology Data Exchange (ETDEWEB)

    Bert Zauderer

    2003-04-21

    Calcium oxide injected in a slagging combustor reacts with the sulfur from coal combustion to form sulfur-bearing particles. The reacted particles impact and melt in the liquid slag layer on the combustor wall by the centrifugal force of the swirling combustion gases. Due to the low solubility of sulfur in slag, it must be rapidly drained from the combustor to limit sulfur gas re-evolution. Prior analyses and laboratory scale data indicated that for Coal Tech's 20 MMBtu/hour, air-cooled, slagging coal combustor slag mass flow rates in excess of 400 lb/hr should limit sulfur re-evolution. The objective of this 42-month project was to validate this sulfur-in-slag model in a group of combustor tests. A total of 36 days of testing on the combustor were completed during the period of performance of this project. This was more that double the 16 test days that were required in the original work statement. The extra tests were made possible by cost saving innovations that were made in the operation of the combustor test facility and in additional investment of Coal Tech resources in the test effort. The original project plan called for two groups of tests. The first group of tests involved the injection of calcium sulfate particles in the form of gypsum or plaster of Paris with the coal into the 20 MMBtu/hour-combustor. The second group of tests consisted of the entire two-step process, in which lime or limestone is co-injected with coal and reacts with the sulfur gas released during combustion to form calcium sulfate particles that impact and dissolve in the slag layer. Since this sulfur capture process has been validated in numerous prior tests in this combustor, the primary effort in the present project was on achieving the high slag flow rates needed to retain the sulfur in the slag.

  2. NONEQUILIBRIUM SULFUR CAPTURE AND RETENTION IN AN AIR COOLED SLAGGING COAL COMBUSTOR

    International Nuclear Information System (INIS)

    Dr. Bert Zauderer

    1999-01-01

    Calcium oxide injected in a slagging combustor reacts with the sulfur from coal combustion to form sulfur-bearing particles. They are deposited on the liquid slag layer on the combustor wall. Due to the low solubility of sulfur in slag, slag must be rapidly drained from the combustor to limit sulfur gas re-evolution. Analysis indicated that slag mass flow rates in excess of 400 lb/hr should limit sulfur re-evolution. The objective of this 42-month project was to perform a series of tests to determine the factors that control the retention of the sulfur in the slag. 36 days of testing on the combustor were completed prior to the end of this reporting period, 12/31/98. This compares with 16 tests required in the original project plan. Combustor tests in early 1997 with high (37%) ash, Indian coal confirmed that high slag mass flow rates of about 500 lb/hr resulted in retention in the slag of up to 20% of the injected sulfur content mineral matter. To further increase the slag flow rate, rice husks, which contain 20% ash, and rice husk char, which contain 70% ash, were co-fired with coal in the combustor. A series of 13 combustor tests were performed in fourth quarter of 1997 and a further 6 tests were performed in January 1998 and in the summer of 1998. The test objective was to achieve slag flow rates between 500 and 1,000 lb/hr. Due to the very low bulk density of rice husk, compared to pulverized coal, almost the entire test effort focused on developing methods for feeding the rice husks into combustor. In the last test of December 1997, a peak mineral matter, injection rate of 592 lb/hr was briefly achieved by injection of coal, rice husk char, gypsum, and limestone into the combustor. However, no significant sulfur concentration was measured in the slag removed from the combustor. The peak injection rate reached with biomass in the 1997 tests was 310 lb/hr with rice husk, and 584 lb/hr with rice husk char

  3. Slagging behavior of upgraded brown coal and bituminous coal in 145 MW practical coal combustion boiler

    Energy Technology Data Exchange (ETDEWEB)

    Akiyama, Katsuya; Pak, Haeyang; Takubo, Yoji [Kobe Steel, Ltd, Kobe (Japan). Mechanical Engineering Research Lab.; Tada, Toshiya [Kobe Steel, Ltd, Takasago (Japan). Coal and Energy Technology Dept.; Ueki, Yasuaki [Nagoya Univ. (Japan). Energy Science Div.; Yoshiie, Ryo; Naruse, Ichiro [Nagoya Univ. (Japan). Dept. of Mechanical Science and Engineering

    2013-07-01

    The purpose of this study is to quantitatively evaluate behaviors of ash deposition during combustion of Upgraded Brown Coal (UBC) and bituminous coal in a 145 MW practical coal combustion boiler. A blended coal consisting 20 wt% of the UBC and 80 wt% of the bituminous coal was burned for the combustion tests. Before the actual ash deposition tests, the molten slag fractions of ash calculated by chemical equilibrium calculations under the combustion condition was adopted as one of the indices to estimate the tendency of ash deposition. The calculation results showed that the molten slag fraction for UBC ash reached approximately 90% at 1,523 K. However, that for the blended coal ash became about 50%. These calculation results mean that blending the UBC with a bituminous coal played a role in decreasing the molten slag fraction. Next, the ash deposition tests were conducted, using a practical pulverized coal combustion boiler. A water-cooled stainless-steel tube was inserted in locations at 1,523 K in the boiler to measure the amount of ash deposits. The results showed that the mass of deposited ash for the blended coal increased and shape of the deposited ash particles on the tube became large and spherical. This is because the molten slag fraction in ash for the blended coal at 1,523 K increased and the surface of deposited ash became sticky. However, the mass of the deposited ash for the blended coal did not greatly increase and no slagging problems occurred for 8 days of boiler operation under the present blending conditions. Therefore, appropriate blending of the UBC with a bituminous coal enables the UBC to be used with a low ash melting point without any ash deposition problems in a practical boiler.

  4. Slagging in a pulverised-coal-fired boiler

    Energy Technology Data Exchange (ETDEWEB)

    Devir, G.P.; Pohl, J.H.; Creelman, R.A. [University of Queensland, St. Lucia, Qld. (Australia). Dept. of Chemical Engineering

    2000-07-01

    This paper describes a technique to evaluate the severity of slagging of a coal in a pulverised-coal-fired boiler. There are few data in the literature on the nature of in-situ boiler slags, their rate of growth and/or their strength properties relevant to sootblowing. The latter is thought to be of more concern to boiler operators and gives rise to the significance of selecting suitable strength tests. As well as standardised methods for characterising pulverised coal performance in a boiler, several novel and less popular techniques are discussed in detail. A suite of three sub-bituminous coals from the Callide Coalfields, Biloela (600 km north of Brisbane), has been selected for slagging tests in the 350 MW{sub e} units of Callide 'B' power station. Disposable air-cooled mild steel slagging probes have been constructed to simulate the conditions for deposit formation in the boiler region. To date, tests for one of these coals has been completed and preliminary results are presented. Once testing for the remaining coals has been completed, it is anticipated that the differences exhibited in deposit growth and strength may be correlated with typical variations in physical and chemical properties of the pulverised coal.

  5. Case cluster of pneumoconiosis at a coal slag processing facility.

    Science.gov (United States)

    Fagan, Kathleen M; Cropsey, Erin B; Armstrong, Jenna L

    2015-05-01

    During an inspection by the Occupational Safety and Health Administration (OSHA) of a small coal slag processing plant with 12 current workers, four cases of pneumoconiosis were identified among former workers. The OSHA investigation consisted of industrial hygiene sampling, a review of medical records, and case interviews. Some personal sampling measurements exceeded the OSHA Permissible Exposure Limit (PEL) for total dust exposures of 15 mg/m(3), and the measured respirable silica exposure of 0.043 mg/m(3), although below OSHA's current PEL for respirable dust containing silica, was above the American Conference of Governmental Industrial Hygienists' Threshold Limit Value (TLV). Chest x-rays for all four workers identified small opacities consistent with pneumoconiosis. This is the first known report of lung disease in workers processing coal slag and raises concerns for workers exposed to coal slag dust. © 2015 Wiley Periodicals, Inc.

  6. A Brief Review of Viscosity Models for Slag in Coal Gasification

    Energy Technology Data Exchange (ETDEWEB)

    Massoudi, Mehrdad; Wang, Ping

    2011-11-01

    Many researchers have defined the phenomenon of 'slagging' as the deposition of ash in the radiative section of a boiler, while 'fouling' refers to the deposition of ash in the convective-pass region. Among the important parameters affecting ash deposition that need to be studied are ash chemistry, its transport, deposit growth, and strength development; removability of the ash deposit; heat transfer mechanisms; and the mode of operation for boilers. The heat transfer at the walls of a combustor depends on many parameters including ash deposition. This depends on the processes or parameters controlling the impact efficiency and the sticking efficiency. For a slagging combustor or furnace, however, the temperatures are so high that much of the coal particles are melted and the molten layer, in turn, captures more particles as it flows. The main problems with ash deposition are reduced heat transfer in the boiler and corrosion of the tubes. Common ways of dealing with these issues are soot blowing and wall blowing on a routine basis; however, unexpected or uncontrolled depositions can also complicate the situation, and there are always locations inaccessible to the use of such techniques. Studies have indicated that slag viscosity must be within a certain range of temperatures for tapping and the membrane wall to be accessible, for example, between 1300 C and 1500 C, the viscosity is approximately 25 Pa {center_dot} s. As the operating temperature decreases, the slag cools and solid crystals begin to form. In such cases the slag should be regarded as a non-Newtonian suspension, consisting of liquid silicate and crystals. A better understanding of the rheological properties of the slag, such as yield stress and shear-thinning, are critical in determining the optimum operating conditions. To develop an accurate heat transfer model in any type of coal combustion or gasification process, the heat transfer and to some extent the rheological properties

  7. Treatment of LF slag to prevent powdering during cooling

    Directory of Open Access Journals (Sweden)

    Ghorai S.

    2017-01-01

    Full Text Available The polymorphic transformation of the monoclinic β-polymorph to the orthorhombic γ-polymorph of di-calcium silicate at around 500°C during cooling results in disintegration of slag. The slag generated, during the production of thermo mechanically treated steel in ladle furnace at M/s Tata Steel Limited, Jamshedpur, India, behaves in similar manner. An attempt has been made to prevent the crumbling of ladle furnace slag. The experiments were conducted in 10 kg air induction furnace. Various types of silica source were used to prevent the disintegration of ladle furnace slag by reducing the basicity and optimizing the additives amount. Apart from silica sources, other additives like borax and barium carbonate were also used to stabilize the β phase. Present investigation reveals that disintegration of ladle furnace slag can be prevented either by addition of 0.2% boarx or 2% barium carbonate. Dust formation can also be prevented by decreasing the ladle furnace slag basicity to about 1.7. Toxicity Characteristic Leaching Procedure test, of the borax and barium carbonate treated slag samples, indicates that barium carbonate treated slag cannot be used for the dusting prevention as it contains high level of barium.

  8. UTILIZATION OF LIGHTWEIGHT MATERIALS MADE FROM COAL GASIFICATION SLAGS

    International Nuclear Information System (INIS)

    None

    1998-01-01

    The integrated-gasification combined-cycle (IGCC) process is an emerging technology that utilizes coal for power generation and production of chemical feedstocks. However, the process generates large amounts of solid waste, consisting of vitrified ash (slag) and some unconverted carbon. In previous projects, Praxis investigated the utilization of ''as-generated'' slags for a wide variety of applications in road construction, cement and concrete production, agricultural applications, and as a landfill material. From these studies, we found that it would be extremely difficult for ''as-generated'' slag to find large-scale acceptance in the marketplace even at no cost because the materials it could replace were abundantly available at very low cost. It was further determined that the unconverted carbon, or char, in the slag is detrimental to its utilization as sand or fine aggregate. It became apparent that a more promising approach would be to develop a variety of value-added products from slag that meet specific industry requirements. This approach was made feasible by the discovery that slag undergoes expansion and forms a lightweight material when subjected to controlled heating in a kiln at temperatures between 1400 and 1700 F. These results confirmed the potential for using expanded slag as a substitute for conventional lightweight aggregates (LWA). The technology to produce lightweight and ultra-lightweight aggregates (ULWA) from slag was subsequently developed by Praxis with funding from the Electric Power Research Institute (EPRI), Illinois Clean Coal Institute (ICCI), and internal resources. The major objectives of the subject project are to demonstrate the technical and economic viability of commercial production of LWA and ULWA from slag and to test the suitability of these aggregates for various applications. The project goals are to be accomplished in two phases: Phase I, comprising the production of LWA and ULWA from slag at the large pilot scale, and

  9. Slag processing system for direct coal-fired gas turbines

    Science.gov (United States)

    Pillsbury, Paul W.

    1990-01-01

    Direct coal-fired gas turbine systems and methods for their operation are provided by this invention. The gas turbine system includes a primary zone for burning coal in the presence of compressed air to produce hot combustion gases and debris, such as molten slag. The turbine system further includes a secondary combustion zone for the lean combustion of the hot combustion gases. The operation of the system is improved by the addition of a cyclone separator for removing debris from the hot combustion gases. The cyclone separator is disposed between the primary and secondary combustion zones and is in pressurized communication with these zones. In a novel aspect of the invention, the cyclone separator includes an integrally disposed impact separator for at least separating a portion of the molten slag from the hot combustion gases.

  10. The effect of primary copper slag cooling rate on the copper valorization in the flotation process

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    Aleksandar Mihajlović

    2015-06-01

    Full Text Available Technological procedure of slow cooling slag from primary copper production is applied in the purpose of copper recovery in the level of 98.5% to blister. This technological procedure is divided into two phases, first slow cooling of slag on the air for 24 hours, and then accelerated cooling with water for 48 hours. Within the research following methods were used: calculation of nonstationary slag cooling, verification of the calculation using computer simulation of slag cooling in the software package COMSOL Multiphysics and experimental verification of simulation results. After testing of the experimentally gained samples of slowly cooled slag it was found that this technological procedure gives the best results in promoting growth or coagulation of dispersed particles of copper sulfide and copper in the slag, thereby increasing the utilization of the flotation process with a decrease of copper losses through very fine particles.

  11. Atmospheric particulate emissions from dry abrasive blasting using coal slag

    Energy Technology Data Exchange (ETDEWEB)

    Bhaskar Kura; Kalpalatha Kambham; Sivaramakrishnan Sangameswaran; Sandhya Potana [University of New Orleans, New Orleans, LA (United States). Department of Civil and Environmental Engineering

    2006-08-15

    Coal slag is one of the widely used abrasives in dry abrasive blasting. Atmospheric emissions from this process include particulate matter (PM) and heavy metals, such as chromium, lead, manganese, nickel. Quantities and characteristics of PM emissions depend on abrasive characteristics and process parameters. Emission factors are key inputs to estimate emissions. Experiments were conducted to study the effect of blast pressure, abrasive feed rate, and initial surface contamination on total PM (TPM) emission factors for coal slag. Rusted and painted mild steel surfaces were used as base plates. Blasting was carried out in an enclosed chamber, and PM was collected from an exhaust duct using U.S. Environment Protection Agency source sampling methods for stationary sources. Results showed that there is significant effect of blast pressure, feed rate, and surface contamination on TPM emissions. Mathematical equations were developed to estimate emission factors in terms of mass of emissions per unit mass of abrasive used, as well as mass of emissions per unit of surface area cleaned. These equations will help industries in estimating PM emissions based on blast pressure and abrasive feed rate. In addition, emissions can be reduced by choosing optimum operating conditions. 40 refs., 5 figs., 2 tabs.

  12. Thermal expansion of slag and fly ash from coal gasification in IGCC power plant

    Energy Technology Data Exchange (ETDEWEB)

    M. Aineto; A. Acosta; J.M.A. Rincon; M. Romero [University of Castilla La Mancha, Ciudad Real (Spain). Laboratory of Applied Mineralogy

    2006-11-15

    Integrated gasification in combined cycle (IGCC) is an electrical power generation system which is characterized to be a clean coal technology different than conventional process in combustible treatment. IGCC process gives rise to inorganic solid wastes in the form of vitreous slag and fly ashes with singular thermal properties. The gasification of the fuel takes place at high temperature and pressure in reducing atmosphere. Under that conditions, gases such as H{sub 2}, N{sub 2} or CO, which are the main components of the gas mixture in the gasifier, show a high solubility in the melt and during the cooling remain enclosed in the vitreous slag. When these wastes are afterward thermal treated in oxidizing conditions, two phenomena occur. The development of a crystalline phase by devitrification of the glassy matrix and the releasing of the enclosed gas, which starts at temperatures nearly to the softening point. At higher temperatures the bubbles with increasing kinetic energy tend to ascend with difficulty through the viscous liquid phase and promotes an expansive reaction, giving rise to a foam glass-ceramic product. This paper has been focused on the study of thermal expansion in slag and fly ash samples from the ELCOGAS IGCC power plant located in Puertollano (Spain). 18 refs., 11 figs., 1 tab.

  13. Radioactivity of coals and ash and slag wastes at coal-fired thermal power plants

    Science.gov (United States)

    Krylov, D. A.; Sidorova, G. P.

    2013-04-01

    This paper presents an analysis of published data on the content of radioactive nuclides in coals originating from various coal deposits, and in ash and slag wastes produced at coal-fired thermal power plants, as well as in fly ash emitted from thermal power plants into the atmosphere. Problems related to the use of coals with an elevated content of natural radionuclides (NRNs) and methods of their solution implemented at the Urtuyskoe coalfield are dealt with. Data on the analysis of Transbaikal coals for the NRN content, as well as weighted mean content of uranium and thorium in coals from the Siberian Region, are given. In order to reduce irradiation of plant personnel and the population of the areas where coal producers and coal-fired thermal power plants are located, it is necessary to organize very careful control of the NRN content in both coals and products of their combustion that are released into the environment. To solve the problem related to the control of radioactivity, the centralized approach and creation of a proper normative base are needed. Experience gained in developing the Urtuyskoe coalfield shows that it is possible to create an efficient system of coal quality control with respect to the radiation hygiene factor and provide protection of the environment and health of the population.

  14. ASPEN Plus simulation of coal integrated gasification combined blast furnace slag waste heat recovery system

    International Nuclear Information System (INIS)

    Duan, Wenjun; Yu, Qingbo; Wang, Kun; Qin, Qin; Hou, Limin; Yao, Xin; Wu, Tianwei

    2015-01-01

    Highlights: • An integrated system of coal gasification with slag waste heat recovery was proposed. • The goal of BF slag heat saving and emission reduction was achieved by this system. • The optimal parameters were obtained and the waste heat recovery rate reached 83.08%. • About 6.64 kmol/min syngas was produced when using one ton BF slag to provide energy. - Abstract: This article presented a model for the system of coal gasification with steam and blast furnace slag waste heat recovery by using the ASPEN Plus as the simulating and modeling tool. Constrained by mass and energy balance for the entire system, the model included the gasifier used to product syngas at the chemical equilibrium based on the Gibbs free energy minimization approach and the boiler used to recover the heat of the blast furnace slag (BF slag) and syngas. Two parameters of temperature and steam to coal ratio (S/C) were considered to account for their impacts on the Datong coal (DT coal) gasification process. The carbon gasification efficiency (CE), cold gasification efficiency (CGE), syngas product efficiency (PE) and the heating value of syngas produced by 1 kg pulverized coal (HV) were adopted as the indicators to examine the gasification performance. The optimal operating temperature and S/C were 800 °C and 1.5, respectively. At this condition, CE reached above 90% and the maximum values of the CGE, PE and HV were all obtained. Under the optimal operating conditions, 1000 kg/min BF slag, about 40.41 kg/min DT pulverized coal and 77.94 kg/min steam were fed into the gasifier and approximate 6.64 kmol/min syngas could be generated. Overall, the coal was converted to clean syngas by gasification reaction and the BF slag waste heat was also recovered effectively (reached up to 83.08%) in this system, achieving the objective of energy saving and emission reduction

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-07-01

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

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

    International Nuclear Information System (INIS)

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

    2008-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Ping Wang

    2013-02-01

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

  18. Natural Radionuclides in Slag/Ash Pile from Coal-Fired Power Plant Plomin

    International Nuclear Information System (INIS)

    Barisic, D.; Lulic, S.; Marovic, G.; Sencar, J.

    2001-01-01

    Full text: The coal slag/ash pile contains about one million tons of different (bottom ash, filter ash, gypsum) waste material deposited in vicinity of Plomin coal-fired power plant. Activities of 40 K, 228 Ra, 226 Ra and 238 U in materials deposited on slag/ash pile as well as in used coals were occasionally measured during past more than two and half decades of Plomin coal-fired plant operation. The radionuclides content in deposited bottom and filter ash material are related with radionuclide activities and mineral matter fraction in coals used. Up to the middle of nineties, the majority of coal used was anthracite from Istrian local mines. In that period, deposited waste material was characterised with relatively high 226 Ra and 238 U activities while potassium and thorium content was very low. When Istrian coal has been completely substituted with imported coal, uranium series radionuclide concentrations in deposited waste materials decreased significantly. Meanwhile, potassium and thorium activities in slag/ash pile material increased. It seems that slag/ash pile material generated in the last several years of Plomin coal-fired power plant operation could be generally used in cement industry without any special restriction. (author)

  19. SLAG CHARACTERIZATION AND REMOVAL USING PULSE DETONATION TECHNOLOGY DURING COAL GASIFICATION

    Energy Technology Data Exchange (ETDEWEB)

    DR. DANIEL MEI; DR. JIANREN ZHOU; DR. PAUL O. BINEY; DR. ZIAUL HUQUE

    1998-07-30

    Pulse detonation technology for the purpose of removing slag and fouling deposits in coal-fired utility power plant boilers offers great potential. Conventional slag removal methods including soot blowers and water lances have great difficulties in removing slags especially from the down stream areas of utility power plant boilers. The detonation wave technique, based on high impact velocity with sufficient energy and thermal shock on the slag deposited on gas contact surfaces offers a convenient, inexpensive, yet efficient and effective way to supplement existing slag removal methods. A slight increase in the boiler efficiency, due to more effective ash/deposit removal and corresponding reduction in plant maintenance downtime and increased heat transfer efficiency, will save millions of dollars in operational costs. Reductions in toxic emissions will also be accomplished due to reduction in coal usage. Detonation waves have been demonstrated experimentally to have exceptionally high shearing capability, important to the task of removing slag and fouling deposits. The experimental results describe the parametric study of the input parameters in removing the different types of slag and operating condition. The experimental results show that both the single and multi shot detonation waves have high potential in effectively removing slag deposit from boiler heat transfer surfaces. The results obtained are encouraging and satisfactory. A good indication has also been obtained from the agreement with the preliminary computational fluid dynamics analysis that the wave impacts are more effective in removing slag deposits from tube bundles rather than single tube. This report presents results obtained in effectively removing three different types of slag (economizer, reheater, and air-heater) t a distance of up to 20 cm from the exit of the detonation tube. The experimental results show that the softer slags can be removed more easily. Also closer the slag to the exit of

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

    Directory of Open Access Journals (Sweden)

    Insoo Ye

    2015-04-01

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

  1. INFLUENCE OF CURING TEMPERATURE ON THE PHYSICO-MECHANICAL, CHARACTERISTICS OF CALCIUM ALUMINATE CEMENT WITH AIR-COOLED SLAG OR WATER-COOLED SLAG

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    M. Heikal

    2004-12-01

    Full Text Available The nature, sequence, crystallinity and microstructure of hydrated phases were analyzed using differential scanning calorimetry (DSC, X-ray diffraction (XRD and scanning electron microscopy (SEM. The results showed that the formation of different hydrated phases was temperature dependence. The physico-mechanical and microstructural characteristics were investigated after curing at 20, 40 and 60° C. The results indicated that for the substitution of calcium aluminate cement (CAC by air-cooled slag (AS or water-cooled slag (WS at 20° C, the compressive strength increases with slag content up to 10 wt.%, then followed by a decrease with further slag substitution up to 25 wt.%; but the values are still higher than those of the neat CAC pastes at different curing ages up to 60 days. After 28 days of hydration at 40-60° C, the compressive strength increases with the slag content. This is attributed to the prevention of the conversion reaction, which was confirmed by XRD, DSC and SEM techniques, and the preferential formation of stratlingite (gehleinte-like phase. The SEM micrographs showed a close texture of hydrated CAC/slag blends made with AS or WS at 40°C due to the formation of C2ASH8 and C-S-H phases.

  2. A Differential Scanning Calorimetry Method for Construction of Continuous Cooling Transformation Diagram of Blast Furnace Slag

    Science.gov (United States)

    Gan, Lei; Zhang, Chunxia; Shangguan, Fangqin; Li, Xiuping

    2012-06-01

    The continuous cooling crystallization of a blast furnace slag was studied by the application of the differential scanning calorimetry (DSC) method. A kinetic model describing the correlation between the evolution of the degree of crystallization with time was obtained. Bulk cooling experiments of the molten slag coupled with numerical simulation of heat transfer were conducted to validate the results of the DSC methods. The degrees of crystallization of the samples from the bulk cooling experiments were estimated by means of the X-ray diffraction (XRD) and the DSC method. It was found that the results from the DSC cooling and bulk cooling experiments are in good agreement. The continuous cooling transformation (CCT) diagram of the blast furnace slag was constructed according to crystallization kinetic model and experimental data. The obtained CCT diagram characterizes with two crystallization noses at different temperature ranges.

  3. Precipitation of metallic chromium during rapid cooling of Cr2O3 slags

    Directory of Open Access Journals (Sweden)

    J. Burja

    2017-01-01

    Full Text Available The slag systems of CaO-SiO2- Cr2O3 and Al2O3-CaO-MgO-SiO2- Cr2O3 were analyzed. These slag systems occur in the production of stainless steel and are important from the process metallurgy point of view. Synthetic slag samples with different chromium oxide content were prepared and melted. The melted slag samples where then rapidly cooled on large steel plates, so that the high temperature microstructure was preserved. The samples were analyzed by scanning electron microscopy (SEM and X-ray diffraction (XRD. The precipitation of different chromium oxide phases was studied, but most importantly the precipitation of metallic chromium was observed. These findings help us interpret industrial slag samples.

  4. Radiation dose contribution from coal-slags used as structural building material

    International Nuclear Information System (INIS)

    Somlai, J.; Kanyar, B.; Bodnar, R.; Lendvai, Z.; Nemeth, Cs.

    1996-01-01

    A significant dose distribution on the population could be derived from coal slags used as isolation material. Extremely high natural activities are measured in the coal slag, derived from the region of the settlement Ajka, Hungary. In some buildings monitored, the elevated γ-doses were nearly 5-10 times higher than the world average ones. The annual average indoor radon concentrations from the slag exceeded 400 Bq/m 3 and in some cases up to 1200 Bq/m 3 . Due to the elevated exposure and the radon concentrations in the dwellings the annual dose was estimated to 8-24 mSv/y more than 5-10 times of the world average one. (author). 10 refs., 1 fig., 3 tabs

  5. Radiation dose contribution from coal-slag from the Ajka region used as structural building material

    Energy Technology Data Exchange (ETDEWEB)

    Somali, J.; Kanyar, B.; Lendvai, Z.; Nemeth, C.; Bodnar, R. [Veszpremi Egyetem, Veszprem (Hungary). Radiokemia Tanszek

    1997-10-01

    A significant dose contribution on the population could be derived from coal slags used as material in buildings. Extremely high natural activities are measured in the coal slag from the region of Ajka, Hungary. The main conclusions based on the results of the monitoring of the gamma-dose rate and the radon concentration in the air in nearly 240 houses are as follows: (1) for individuals, such as children, spending a long time at home (19.2 h/day) the external annual dose is 1.7-4.5 mSv; (2) in the majority of houses with local slag the estimated annual average value of indoor-radon concentration was above 400 Bq/m{sup 3}, and in several cases there were buildings with values over 1200 Bq/m{sup 3}. In these cases the internal annual dose of the dwellers can be estimated between 6-20 mSv; (3) due to the elevated gamma-exposure and the radon concentration in the dwellings the total annual dose was estimated as 8-24 mSv, more than 5-10 times the world average value; and (4) some of the houses were built after the 1960s, when the use of slags from the region of Ajka as building material was already banned by the authorities. In addition to the regulations an effective radiological control should be introduced and a practice for testing the use of slag as building material.

  6. Organosilicon fluid for cooling coal combine motors

    Energy Technology Data Exchange (ETDEWEB)

    Donets, I K; Dmitrenko, Yu N; Kovalev, Ye B; Sukhanov, V V; Tsingarelli, Ye P

    1983-01-01

    Results are presented of toxicological evaluation of the polymer organosilicon fluid FM-5.6AP which should be used as the cooling agent of the electric motors of coal combines. It was established that fluid FM-5.6AP belongs to the low-toxic substances that do not have skinresorptive, skin-damaging and cumulative effect, do not have a significant influence on phagocytosis of the coal dust, in depositing in the lungs and elimination. During experimental industrial tests of the motor using the fluid FM-5.6AP, no toxic effect of it on the body was revealed. The possibility is shown of using organosilicon fluid FM-5.6AP for cooling electric motors of coal combines.

  7. Minerals in the Ash and Slag from Oxygen-Enriched Underground Coal Gasification

    Directory of Open Access Journals (Sweden)

    Shuqin Liu

    2016-03-01

    Full Text Available Underground coal gasification (UCG is a promising option for the recovery of low-rank and inaccessible coal resources. Detailed mineralogical information is essential to understand underground reaction conditions far from the surface and optimize the operation parameters during the UCG process. It is also significant in identifying the environmental effects of UCG residue. In this paper, with regard to the underground gasification of lignite, UCG slag was prepared through simulation tests of oxygen-enriched gasification under different atmospheric conditions, and the minerals were identified by X-Ray diffraction (XRD and a scanning electron microscope coupled to an energy-dispersive spectrometer (SEM-EDS. Thermodynamic calculations performed using FactSage 6.4 were used to help to understand the transformation of minerals. The results indicate that an increased oxygen concentration is beneficial to the reformation of mineral crystal after ash fusion and the resulting crystal structures of minerals also tend to be more orderly. The dominant minerals in 60%-O2 and 80%-O2 UCG slag include anorthite, pyroxene, and gehlenite, while amorphous substances almost disappear. In addition, with increasing oxygen content, mullite might react with the calcium oxide existed in the slag to generate anorthite, which could then serve as a calcium source for the formation of gehlenite. In 80%-O2 UCG slag, the iron-bearing mineral is transformed from sekaninaite to pyroxene.

  8. Is coal ash and slag any useful or unloaded wastes?

    International Nuclear Information System (INIS)

    Botezatu, E.; Grecea, C.; Iacob, O.

    2002-01-01

    It is well known that all types of coal, like most materials found in nature, contain trace quantities of the naturally occurring primordial radionuclides (uranium and thorium families and potassium-40). Therefore, the combustion of coal results in partitioning of radionuclides included in the non-combustible mineral matter, between the bottom ash and fly ash, and in the release into the environment of large amounts of coal ash. Emissions from thermal power stations in gaseous and particulate form contain radioisotopes arising from the uranium and thorium series as well as from 4 0K . They are discharged into the environment causing changes in the natural radiation background and radiation exposures to the population. The continued releases of these materials to environment may result in a buildup in the air, water and soil of the radionuclides, particularly radium-226. There will be an increase of the basic radiation rate in the neighborhood area of these plants and consequently relatively higher exposure of the local population to radiation. Coal burning is, therefore, one of the sources of technologically enhanced exposure to humans from natural radionuclides (1,2,3,4,5,6). Coal based thermal power plants constitute about 35% of quantum of energy supply in Romania. In view of the importance of coal for energy supply in Romania, we were interested in knowing possible uses of the resulting wastes and minimize the following harmful consequences of coal burning

  9. Method of burning highly reactive strongly slagging coal dust in a chamber furnace

    Energy Technology Data Exchange (ETDEWEB)

    Protsaylo, M.Ya.; Kotler, V.R.; Lobov, G.V.; Mechev, V.P.; Proshkin, A.V.; Zhuravlev, Yu.A.

    1982-01-01

    In the chamber furnace in order to reduce slagging, it is proprosed that, above the coal dust burners, nozzles be installed with inclination downwards through which air is fed in a mixture with flue gases. Under the influence of this flue gas-air mixture, the coal dust flame is deviated downwards. In this case there is an increase in the length of the flame and degree of filling of the volume of the furnace with the flame. This increases the effectiveness of dust burning. The input into the furnace of fuel jointly with the air and flue gases (optimally 10-15% of the total quantity of gases formed during fuel combustion) makes it possible to reduce the temperature in the furnace and the probability of slagging of the furnace walls.

  10. Radiological characterization of the coal ash and slag from Kastel Gomilica, Croatia

    International Nuclear Information System (INIS)

    Lovrencic, I.; Orescanin, V.; Barisic, D.; Mikelic, L.; Rozmaric Macefat, M.; Lulic, St.; Pavlovic, G.

    2006-01-01

    The objective of this study was radiological characterization of slag and ash produced in a thermo electric unit of the former 'Adriavinil' chemical factory as a by-product of coal combustion and deposited in the Kastel Gomilica region, Croatia. The waste material was deposited in the 'old' regulated and the 'new' unregulated part of the depot. 33 samples were analyzed to obtain a preliminary data on the present state of the new unregulated part of the depot. Activities of the selected radionuclides (40 K, 232 Th, 235 U and 226 Ra) were measured using gamma-spectrometry method. 238 U activity was calculated from the assumed natural 235 U /238 U activity ratio. It is found that there is a dependence of the activities of the selected radionuclides on the activities of the coal used for energy production in the power unit. The content of 232 Th, 226 Ra and 238 U in slag and ash increased several times during the combustion process. Investigated slag and ash showed a significant variability in their activities of selected radionuclides due to a different origin of coal used in the thermoelectric unit of the factory. The waste material was characterized by high activity of naturally occurring 238 U, 235 U and 226 Ra. 226 Ra and 238 U activities were up to 50 times higher than their average activities characteristic for surrounding soils developed on flysch sediments. 40 K and 232 Th showed no elevation compared to soil activities. Mineralogical analysis has been made as well. (authors)

  11. Recovery of Copper from Slow Cooled Ausmelt Furnace Slag by Floatation

    Science.gov (United States)

    Xue, Ping; Li, Guangqiang; Qin, Qingwei

    Ausmelt furnace slag contains about 0.9% Cu (mass %). With increasing the amount of Ausmelt furnace slag, the recovery of copper from it will produce an enormous economic yield. The recovery of copper by floatation from slow cooled Ausmelt furnace slag was studied in this paper. The phases and composition of the slow cooled slag were analyzed. The factors which affected the copper recovery efficiency such as grinding fineness, pH value of flotation medium, different collectors and floating process were investigated. It was shown that the size distribution of the primary grinding and secondary grinding of middling were 75% for particles less than 0.074mm and 82% for particles less than 0.043mm respectively. The closed-circuit experimental results with butyl xanthate as collector in laboratory showed that the copper grade reached 16.11% and the recovery rate of copper reached 69.90% and the copper grade of tailings was only 0.2%.

  12. Non-slag co-gasification of biomass and coal in entrained-bed furnace

    Science.gov (United States)

    Itaya, Yoshinori; Suami, Akira; Kobayashi, Nobusuke

    2018-02-01

    Gasification is a promising candidate of processes to upgrade biomass and to yield clean gaseous fuel for utilization of renewable energy resources. However, a sufficient amount of biomass is not always available to operate a large scale of the plant. Co-gasification of biomass with coal is proposed as a solution of the problem. Tar emission is another subject during operation in shaft or kiln type of gasifiers employed conventionally for biomass. The present authors proposed co-gasification of biomass and coal in entrained-bed furnace, which is a representative process without tar emission under high temperature, but operated so to collect dust as flyash without molten slag formation. This paper presents the works performed on co-gasification performance of biomass and pulverized coal to apply to entrained-bed type of furnaces. At first, co-gasification of woody powder and pulverized coal examined using the lab-scale test furnace of the down-flow entrained bed showed that the maximum temperatures in the furnace was over 1500 K and the carbon conversion to gas achieved at higher efficiency than 80-90 percent although the residence time in the furnace was as short as a few seconds. Non-slag co-gasification was carried out successfully without slag formation in the furnace if coal containing ash with high fusion temperature was employed. The trend suggesting the effect of reaction rate enhancement of co-gasification was also observed. Secondary, an innovative sewage sludge upgrading system consisting of self-energy recovery processes was proposed to yield bio-dried sludge and to sequentially produce char without adding auxiliary fuel. Carbonization behavior of bio-dried sludge was evaluated through pyrolysis examination in a lab-scale quartz tube reactor. The thermal treatment of pyrolysis of sludge contributed to decomposition and removal of contaminant components such as nitrogen and sulfur. The gasification kinetics of sludge and coal was also determined by a

  13. Resistance of Alkali Activated Water-Cooled Slag Geopolymer to Sulphate Attack

    Directory of Open Access Journals (Sweden)

    S. A. Hasanein

    2011-06-01

    Full Text Available Ground granulated blast furnace slag is a finely ground, rapidly chilled aluminosilicate melt material that is separated from molten iron in the blast furnace as a by-product. Rapid cooling results in an amorphous or a glassy phase known as GGBFS or water cooled slag (WCS. Alkaline activation of latent hydraulic WCS by sodium hydroxide and/or sodium silicate in different ratios was studied. Curing was performed under 100 % relative humidity and at a temperature of 38°C. The results showed that mixing of both sodium hydroxide and sodium silicate in ratio of 3:3 wt.,% is the optimum one giving better mechanical as well as microstructural characteristics as compared with cement mortar that has various cement content (cement : sand were 1:3 and 1:2. Durability of the water cooled slag in 5 % MgSO4 as revealed by better microstructure and high resistivity-clarifying that activation by 3:3 sodium hydroxide and sodium silicate, respectively is better than using 2 and 6 % of sodium hydroxide.

  14. Coal ash fusion temperatures - new characterization techniques and implications for slagging and fouling

    Energy Technology Data Exchange (ETDEWEB)

    Wall, T.F.; Creelman, R.A.; Gupta, R.P.; Gupta, S.K.; Coin, C.; Lowe, A. [University of Newcastle, Newcastle, NSW (Australia). CRC for Black Coal Utilisation

    1998-09-01

    The ash fusion test (AFT) is the accepted test for the propensity of coal ash to slag in the furnace. The well-documented shortcomings of this technique for estimating the fusion temperature of coal ash are its subjective nature and poor accuracy. Alternative measurements based on the shrinkage and electrical conductivity of heating samples are therefore examined here with laboratory ash prepared at about 800{degree}C in crucibles, as well as combustion ash samples from power stations. Sensitive shrinkage measurements indicate temperatures of rapid change which correspond to the formation of liquid phases that can be identified on ternary phase diagrams. The existence and extent of formation of these phases, as quantified by the magnitude of `peaks` in the test, provide alternative ash fusion temperatures. The peaks from laboratory ashes and corresponding combustion ashes derived from the same coals show clear differences which may be related to the evaporation of potassium during combustion and the reactions of the mineral residues to form combustion ash. A preliminary evaluation of data from nine power stations indicates that shrinkage measurements can provide an alternative approach to characterizing slagging. 15 refs., 9 figs., 2 tabs.

  15. Radiological characterization of the coal ash and slag from Kastel Gomilica, Croatia

    Energy Technology Data Exchange (ETDEWEB)

    Lovrencic, I.; Orescanin, V.; Barisic, D.; Mikelic, L.; Rozmaric Macefat, M.; Lulic, St. [Rudjer Boskovic Institute, Zagreb (Croatia); Pavlovic, G. [Zagreb Univ., Faculty of Science, Dept. of Mineralogy and Petrography (Croatia)

    2006-07-01

    objective of this study was radiological characterization of slag and ash produced in a thermo electric unit of the former 'Adriavinil' chemical factory as a by-product of coal combustion and deposited in the Kastel Gomilica region, Croatia. The waste material was deposited in the 'old' regulated and the 'new' unregulated part of the depot. 33 samples were analyzed to obtain a preliminary data on the present state of the new unregulated part of the depot. Activities of the selected radionuclides (40 K, 232 Th, 235 U and 226 Ra) were measured using gamma-spectrometry method. 238 U activity was calculated from the assumed natural 235 U /238 U activity ratio. It is found that there is a dependence of the activities of the selected radionuclides on the activities of the coal used for energy production in the power unit. The content of 232 Th, 226 Ra and 238 U in slag and ash increased several times during the combustion process. Investigated slag and ash showed a significant variability in their activities of selected radionuclides due to a different origin of coal used in the thermoelectric unit of the factory. The waste material was characterized by high activity of naturally occurring 238 U, 235 U and 226 Ra. 226 Ra and 238 U activities were up to 50 times higher than their average activities characteristic for surrounding soils developed on flysch sediments. 40 K and 232 Th showed no elevation compared to soil activities. Mineralogical analysis has been made as well. (authors)

  16. Evaluation of radioactivity levels of coal, slag and fly ash samples used in Giresun province of Turkey

    International Nuclear Information System (INIS)

    Kara, A.; Chevik, U.; Damla, N.; Yeshilbag, Y.O.

    2010-01-01

    In present work natural radionuclides activities (236Ra, 232Th and 40K) of the different types of coal, slag and fly ash samples used in Giresun province (Eastern Black Sea region of Turkey) were measured by using gamma-ray spectrometry. These samples were collected as homogeneously and separately around Giresun province. The mean activity concentrations of 226Ra, 232Th and 40K radionuclides in coal, slag and fly ash samples were found as 107, 67 and 440 Bg.Kg - 1 for coal; 59, 25 and 268 Bg.kg - 1 for slag and 136, 60 and 417 Bg.kg - 1 for fly ash samples, respectively. To estimate health effect due to the aforementioned radionuclides, absorbed dose rates and annual effective doses have been calculated. These values were evaluated and compared with the internationally recommended values

  17. Influences of coal slag on electrical characteristics of a Faraday MHD generator

    International Nuclear Information System (INIS)

    Yoshida, M.; Umoto, J.

    1989-01-01

    In order to clarify the influence of coal slag on the electrical characteristics of a large scale Faraday MHD generator, numerical analysis by a new equivalent circuit method is performed. At first, an equivalent circuit for a space element in the Faraday channel and a slag layer element are derived. Next, the numerical results are compared with the experimental ones obtained from the ETL Mark VII. The results are: (1) when the thickness, conductivity, etc. of the slag are nonuniform the distribution of not only the load voltage, but also the voltage between adjacent electrodes, becomes nonuniform, and the latter may cause interelectrode breakdown; (2) when shorting over several cathodes occurs a typical distribution of the load voltage appears near the shorted region, in which, at first, the load voltage rises a little, then decreases gradually, and finally, recovers rapidly to the normal voltage along the gas flow. As a result of the short-circuit, the distribution of the voltage between adjacent electrodes is made significantly nonuniform, and this may lead to another inter-electrode breakdown. (author)

  18. Zinc estimates in ore and slag samples and analysis of ash in coal samples

    International Nuclear Information System (INIS)

    Umamaheswara Rao, K.; Narayana, D.G.S.; Subrahmanyam, Y.

    1984-01-01

    Zinc estimates in ore and slag samples were made using the radioisotope X-ray fluorescence method. A 10 mCi 238 Pu was employed as the primary source of radiation and a thin crystal NaI(Ti) spectrometer was used to accomplish the detection of the 8.64 keV Zinc K-characteristic X-ray line. The results are reported. Ash content of coal concerning about 100 samples from Ravindra Khani VI and VII mines in Andhra Pradesh were measured using X-ray backscattering method with compensation for varying concentrations of iron in different coal samples through iron-X-ray fluorescent intensity measurements. The ash percent is found to range from 10 to 40. (author)

  19. Unexpected Dominance of Elusive Acidobacteria in Early Industrial Soft Coal Slags

    Directory of Open Access Journals (Sweden)

    Carl-Eric Wegner

    2017-06-01

    Full Text Available Acid mine drainage (AMD and mine tailing environments are well-characterized ecosystems known to be dominated by organisms involved in iron- and sulfur-cycling. Here we examined the microbiology of industrial soft coal slags that originate from alum leaching, an ecosystem distantly related to AMD environments. Our study involved geochemical analyses, bacterial community profiling, and shotgun metagenomics. The slags still contained high amounts of alum constituents (aluminum, sulfur, which mediated direct and indirect effects on bacterial community structure. Bacterial groups typically found in AMD systems and mine tailings were not present. Instead, the soft coal slags were dominated by uncharacterized groups of Acidobacteria (DA052 [subdivision 2], KF-JG30-18 [subdivision 13], Actinobacteria (TM214, Alphaproteobacteria (DA111, and Chloroflexi (JG37-AG-4, which have previously been detected primarily in peatlands and uranium waste piles. Shotgun metagenomics allowed us to reconstruct 13 high-quality Acidobacteria draft genomes, of which two genomes could be directly linked to dominating groups (DA052, KF-JG30-18 by recovered 16S rRNA gene sequences. Comparative genomics revealed broad carbon utilization capabilities for these two groups of elusive Acidobacteria, including polysaccharide breakdown (cellulose, xylan and the competence to metabolize C1 compounds (ribulose monophosphate pathway and lignin derivatives (dye-decolorizing peroxidases. Equipped with a broad range of efflux systems for metal cations and xenobiotics, DA052 and KF-JG30-18 may have a competitive advantage over other bacterial groups in this unique habitat.

  20. Dissolved organic matter removal during coal slag additive soil aquifer treatment for secondary effluent recharging: Contribution of aerobic biodegradation.

    Science.gov (United States)

    Wei, Liangliang; Li, Siliang; Noguera, Daniel R; Qin, Kena; Jiang, Junqiu; Zhao, Qingliang; Kong, Xiangjuan; Cui, Fuyi

    2015-06-01

    Recycling wastewater treatment plant (WWTP) effluent at low cost via the soil aquifer treatment (SAT), which has been considered as a renewable approach in regenerating potable and non-potable water, is welcome in arid and semi-arid regions throughout the world. In this study, the effect of a coal slag additive on the bulk removal of the dissolved organic matter (DOM) in WWTP effluent during SAT operation was explored via the matrix configurations of both coal slag layer and natural soil layer. Azide inhibition and XAD-resins fractionation experiments indicated that the appropriate configuration designing of an upper soil layer (25 cm) and a mixture of soil/coal slag underneath would enhance the removal efficiency of adsorption and anaerobic biodegradation to the same level as that of aerobic biodegradation (31.7% vs 32.2%), while it was only 29.4% compared with the aerobic biodegradation during traditional 50 cm soil column operation. The added coal slag would preferentially adsorb the hydrophobic DOM, and those adsorbed organics could be partially biodegraded by the biomass within the SAT systems. Compared with the relatively lower dissolved organic carbon (DOC), ultraviolet light adsorption at 254 nm (UV-254) and trihalomethane formation potential (THMFP) removal rate of the original soil column (42.0%, 32.9%, and 28.0%, respectively), SSL2 and SSL4 columns would enhance the bulk removal efficiency to more than 60%. Moreover, a coal slag additive in the SAT columns could decline the aromatic components (fulvic-like organics and tryptophan-like proteins) significantly. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Investigation of pyrite as a contributor to slagging in eastern bituminous coals. Quarterly progress report 9, October 1-December 31, 1983

    Energy Technology Data Exchange (ETDEWEB)

    Bryers, R.W.

    1984-06-01

    The objective of this program is to examine slags formed as a result of firing coals with varying concentration levels, size distribution, and orientation of pyrite with regard to mineral matter in the coal in a laboratory furnace. The program tasks are: (1) selection of eight candidate coals; (2) chemical characterization of the coal samples and identification of the pyrite size, distribution, and orientation with respect to other mineral matter and concentration levels; (3) testing of the candidate coals in a laboratory furnace; (4) chemical and physical characterization of the slag and fly ash samples created by the impurities in the coal sample; (5) influence of coal beneficiation on furnace slagging; and (6) analysis of data and identification of parameters influencing the contribution of pyrite to slagging problems. Washing of the Upper Freeport coal from Indiana County, Pennsylvania, was completed by the last quarter of 1983. The washed product was characterized for mineral content, and a combustion test was performed. Kentucky No. 9 from Henderson County, Kentucky, selected as the sixth coal to be investigated, was characterized using size and gravity fractionation techniques and was combusted in the laboratory furnace to evaluate its slagging and fouling potential. The remaining two coals to be characterized and combusted were identified as Illinois No. 5 and Lower Kittanning from Clarion County, Pennsylvania. 80 figures, 27 tables.

  2. Experimental evaluation of sorbents for sulfur control in a coal-fueled gas turbine slagging combustor

    International Nuclear Information System (INIS)

    Cowell, L.H.; Wen, C.S.; LeCren, R.T.

    1992-01-01

    This paper reports on a slagging combustor that has been used to evaluate three calcium-based sorbents for sulfur capture efficiency in order to assess their applicability for use in a oil-fueled gas turbine. Testing is competed in a bench-scale combustor with one-tenth the heat input needed for the full-scale gas turbine. The bench-scale rig is a two-stage combustor featuring a fuel-rich primary zone an a fuel-lean secondary zone. The combustor is operated at 6.5 bars with inlet air preheated to 600 K. Gas temperatures of 1840 K are generated in the primary zone and 1280 K in the secondary zone. Sorbents are either fed into the secondary zone or mixed with the coal-water mixture and fed into the primary zone. Dry powered sorbents are fed into the secondary zone by an auger into one of six secondary air inlet ports. The three sorbents tested in the secondary zone include dolomite, pressure-hydrated dolomitic lime, and hydrated lime. Sorbents have been tested while burning coal-water mixtures with coal sulfur loadings of 0.56 to 3.13 weight percent sulfur. Sorbents are injected into the secondary zone at varying flow rates such that the calcium/sulfur ratio varies from 0.5 to 10.0

  3. Influence of coal ash and slag dumping on dump waste waters of the Kostolac power plants (Serbia)

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, A.; Djinovic, J. [University of Belgrade, Belgrade (Serbia)

    2006-10-01

    The content of selected trace and major elements in the river water used for transport, as well as in the subcategories of the waste waters (overflow and drainage) were analyzed in order to establish the influence of transport and dumping of coal ash and slag from the 'Kostolac A' and 'Kostolac B' power plants located 100 km from Belgrade (Serbia). It was found that during transport of coal ash and slag to the dump, the water used for transport becomes enriched with manganese, nickel, zinc, chromium, vanadium, titanium, cobalt, arsenic, aluminum, and silicon, while more calcium, iron, cadmium, and lead are adsorbed by the ash and slag than is released from them. There is also an equilibrium between the release and adsorption processes of copper and magnesium during transport. The vertical penetration of the water used for transport results in a release of calcium, magnesium, manganese, and cadmium to the environment, while iron, nickel, zinc, chromium, copper, lead, vanadium, titanium, cobalt, and arsenic are adsorbed by the fractions of coal ash and slag in the dump.

  4. Slag Behavior in Gasifiers. Part II: Constitutive Modeling of Slag

    Energy Technology Data Exchange (ETDEWEB)

    Massoudi, Mehrdad [National Energy Technology Laboratory; Wang, Ping

    2013-02-07

    The viscosity of slag and the thermal conductivity of ash deposits are among two of the most important constitutive parameters that need to be studied. The accurate formulation or representations of the (transport) properties of coal present a special challenge of modeling efforts in computational fluid dynamics applications. Studies have indicated that slag viscosity must be within a certain range of temperatures for tapping and the membrane wall to be accessible, for example, between 1,300 °C and 1,500 °C, the viscosity is approximately 25 Pa·s. As the operating temperature decreases, the slag cools and solid crystals begin to form. Since slag behaves as a non-linear fluid, we discuss the constitutive modeling of slag and the important parameters that must be studied. We propose a new constitutive model, where the stress tensor not only has a yield stress part, but it also has a viscous part with a shear rate dependency of the viscosity, along with temperature and concentration dependency, while allowing for the possibility of the normal stress effects. In Part I, we reviewed, identify and discuss the key coal ash properties and the operating conditions impacting slag behavior.

  5. Co-combustion of anthracite coal and wood pellets: Thermodynamic analysis, combustion efficiency, pollutant emissions and ash slagging.

    Science.gov (United States)

    Guo, Feihong; Zhong, Zhaoping

    2018-08-01

    This work presents studies on the co-combustion of anthracite coal and wood pellets in fluidized bed. Prior to the fluidized bed combustion, thermogravimetric analysis are performed to investigate the thermodynamic behavior of coal and wood pellets. The results show that the thermal decomposition of blends is divided into four stages. The co-firing of coal and wood pellets can promote the combustion reaction and reduce the emission of gaseous pollutants, such as SO 2 and NO. It is important to choose the proportion of wood pellets during co-combustion due to the low combustion efficiency caused by large pellets with poor fluidization. Wood pellets can inhibit the volatilization of trace elements, especially for Cr, Ni and V. In addition, the slagging ratio of wood pellets ash is reduced by co-firing with coal. The research on combustion of coal and wood pellets is of great significance in engineering. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Preparation of steel slag porous sound-absorbing material using coal powder as pore former.

    Science.gov (United States)

    Sun, Peng; Guo, Zhancheng

    2015-10-01

    The aim of the study was to prepare a porous sound-absorbing material using steel slag and fly ash as the main raw material, with coal powder and sodium silicate used as a pore former and binder respectively. The influence of the experimental conditions such as the ratio of fly ash, sintering temperature, sintering time, and porosity regulation on the performance of the porous sound-absorbing material was investigated. The results showed that the specimens prepared by this method had high sound absorption performance and good mechanical properties, and the noise reduction coefficient and compressive strength could reach 0.50 and 6.5MPa, respectively. The compressive strength increased when the dosage of fly ash and sintering temperature were raised. The noise reduction coefficient decreased with increasing ratio of fly ash and reducing pore former, and first increased and then decreased with the increase of sintering temperature and time. The optimum preparation conditions for the porous sound-absorbing material were a proportion of fly ash of 50% (wt.%), percentage of coal powder of 30% (wt.%), sintering temperature of 1130°C, and sintering time of 6.0hr, which were determined by analyzing the properties of the sound-absorbing material. Copyright © 2015. Published by Elsevier B.V.

  7. Integration of coal gasification and waste heat recovery from high temperature steel slags: an emerging strategy to emission reduction

    Science.gov (United States)

    Sun, Yongqi; Sridhar, Seetharaman; Liu, Lili; Wang, Xidong; Zhang, Zuotai

    2015-01-01

    With the continuous urbanization and industrialization in the world, energy saving and greenhouse gas (GHG) emission reduction have been serious issues to be addressed, for which heat recovery from traditional energy-intensive industries makes up a significant strategy. Here we report a novel approach to extract the waste heat and iron from high temperature steel slags (1450–1650 oC) produced in the steel industry, i.e., integration of coal gasification and steel slag treatment. Both the thermodynamics and kinetics of the pertinent reactions were identified. It was clarified that the kinetic mechanism for gasification varied from A2 model to A4 model (Avrami-Erofeev) in the presence of slags. Most importantly, the steel slags acted not only as good heat carriers but also as effective catalysts where the apparent activation energy for char gasification got remarkably reduced from 95.7 kJ/mol to 12.1 kJ/mol (A2 model). Furthermore, the FeO in the slags was found to be oxidized into Fe3O4, with an extra energy release, which offered a potential for magnetic separation. Moreover, based on the present research results, an emerging concept, composed of multiple industrial sectors, was proposed, which could serve as an important route to deal with the severe environmental problems in modern society. PMID:26558350

  8. Leaching properties of slag generated by a gasification/vitrification unit: the role of pH, particle size, contact time and cooling method used.

    Science.gov (United States)

    Moustakas, K; Mavropoulos, A; Katsou, E; Haralambous, K J; Loizidou, M

    2012-03-15

    The environmental impact from the operation of thermal waste treatment facilities mainly originates from the air emissions, as well as the generated solid residues. The objective of this paper is to examine the slag residue generated by a demonstration plasma gasification/vitrification unit and investigate the composition, the leaching properties of the slag under different conditions, as well as the role of the cooling method used. The influence of pH, particle size and contact time on the leachability of heavy metals are discussed. The main outcome is that the vitrified slag is characterized as inert and stable and can be safely disposed at landfills or used in the construction sector. Finally, the water-cooled slag showed better resistance in relation to heavy metal leachability compared to the air-cooled slag. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Characterization of coal gasification slag-based activated carbon and its potential application in lead removal.

    Science.gov (United States)

    Xu, Yiting; Chai, Xiaoli

    2018-02-01

    Highly porous activated carbons were prepared from a coal gasification slag (CGS) precursor, by KOH activation to remove Pb 2+ from aqueous solution. The effects of pretreatment methods and activation parameters on the properties of the activated carbon were investigated, such as KOH/CGS mass ratio, activation temperature and activation time. The results showed that the maximum Brunauer-Emmett-Teller surface area and total pore volume with the value of 2481 m 2  g -1 and of 1.711 cc g -1 were obtained at a KOH/CGS ratio of 3.0 by physical mixing, an activation temperature of 750°C and an activation time of 80 min. SEM, FTIR and EA analyses indicated that pronounced pores existed on the exterior surface of the activated samples, and the contents of H and O decreased due to the loss of surface chemical groups during activation. Experimental data for the Pb 2+ adsorption were fitted well by Freundlich equation and a pseudo-second-order model with a maximum experimental adsorption capacity of 141 mg/g. All of the results indicated that CGS could be a promising material to prepare porous activated carbon for Pb 2+ removal from wastewater.

  10. Ash fusion temperatures and their association with the transformations of coal ash particles to slag

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.K.; Wall, T.F.; Gupta, R.P. [Cooperative Research Centre for Black Coal Utilisation, Newcastle, NSW (Australia); Creelman, R.A. [Creelman (R.A.) and Associates, Sydney, NSW (Australia)

    1997-04-01

    Ash deposition on furnace walls in PF (pulverized fuel) furnaces is called slagging when it occurs in the high temperature areas of furnaces directly exposed to flame radiation and fouling in other regions such as tubes in the convection section of the boiler. There are well documented shortcomings of certain approaches relating to their uncertainties as predictive tools for plant performance such as poor repeatability and re-producibility of ash fusion measurements. The nature of physical and chemical changes occurring during melting of coal ash has been investigated in the current study to provide an alternative procedure to the ash fusion test. Shrinkage measurements are frequently used in metallurgy and ceramic science to study the physical properties of materials at high temperatures. The output of this experiment provides three to four `peaks` (maximum rate of shrinkage with temperature) of different intensity and at different temperatures which are related to melting characteristics of the sample. It was concluded that shrinkage extents exceeding 50 percent indicated that the effect of the ash particle size is of secondary importance compared to ash chemistry in determining shrinkage levels, with fine particles giving rapid shrinkage events 10 degrees C lower in temperature. (author). 7 figs., refs.

  11. Electrochemical corrosion of lanthanum chromite and yttrium chromite in coal slag

    Energy Technology Data Exchange (ETDEWEB)

    Marchant, D.D.; Bates, J.L.

    1981-01-01

    Lanthanum chromites have long been considered as electrodes for magnetohydrodynamic (MHD) generator channels. These chromites, when doped with divalent ions such as Ca, Mg or Sr, have adequate electronic and electrical conductivity (2), and melting points greater than 2500/sup 0/K. However, above approx. 1850/sup 0/K, selective vapor loss of chromium results in the formation of a La/sub 2/O/sub 3/ phase. The La/sub 2/O/sub 3/ is hydroscopic at room temperature, resulting in a large volume change and loss of mechanical integrity when exposed to H/sub 2/O. The analogous yttrium chromites have thermal and electrical properties similar to that for the lanthanum chromites. Although vapor loss of Cr results in the formation of Y/sub 2/O/sub 3/, this oxide does not hydrate. Corrosion studies of yttrium chromite compositions show that doped YCrO/sub 3/ may be a viable MHD electrode. An electrochemical corrosion study of both magnesium-doped lanthanum and yttrium chromites in synthetic coal slag electrolytes is described. Possible chemical and electrochemical degradation phenomena, as well as the relative rates of corrosion are emphasized.

  12. Ash fusion temperatures and the transformations of coal ash particles to slag

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.K.; Wall, T.F.; Creelman, R.A.; Gupta, R.P. [University of Newcastle, Newcastle, NSW (Australia). CRC for Black Coal Utilisation

    1998-07-01

    A mechanistic study is detailed in which coal ash is heated with its shrinkage measured continuously up to a temperature of 1600{degree}C. The temperature corresponding to the rapid rate of shrinkage correspond to the formation of eutectics identified on phase diagrams. Samples were therefore heated to these temperatures, cooled rapidly and examined using a scanning electron microscope (SEM) to identify the associated chemical and physical changes. The progressive changes in the range of chemical composition (from SEM), the extent of undissolved ash particles and porosity were then quantified and related to homogenisation, viscosity and ash fusion mechanisms. Alternate ash fusion temperatures based on different levels of shrinkage have also been suggested to characterise the ash deposition tendency of the coals. 13 refs., 9 figs.

  13. Slag characterization and removal using pulse detonation for coal gasification. Quarterly research report, January 1, 1996--March 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Huque, Z.; Mei, D.; Biney, P.O.; Zhou, J.

    1996-03-25

    Microbeam Technologies Incorporated (MTI) is working with Prairie View to develop and demonstrate a new method to remove deposits from coal-fired utility boilers. MTI is providing background information on fuel properties, ash formation, ash deposition, and ash removal. In addition, MTI is providing deposits collected from a full scale utility boilers. Ash deposits on fireside heat exchange surfaces of power plants significantly decrease plant efficiency and are aggravated by variability in coal quality. Deposit formation is related to coal quality (chemical and physical characteristics of the inorganic material), system operating conditions, and system design. Variations in coal quality can significantly influence ash deposition on heat transfer surfaces resulting in decreased plant performance and availability. Ash accumulations on heat transfer surfaces require annual or semi-annual shutdowns for cleaning which result in cleaning costs and lost revenues from being off-line. In addition, maintaining slag flow in wet bottom boilers and cyclone-fired boilers can require co-firing of other fuels and outages to remove frozen slag resulting in decreased efficiency and availability. During this reporting period MTI performed analysis of deposits collected from full-scale utility boilers. Deposit samples were obtained from Basin Electric and from Northern States Power (NSP). The analyses were conducted using scanning electron microscopy/microprobe techniques as described in the past quarterly report. The chemical and physical properties of the deposits were determined. The results for sample collected from NSP`s Riverside plant are reported here.

  14. Ash fusion temperatures and the transformations of coal ash particles to slag

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, S.; Wall, T.F.; Creelman, R.A.; Gupta, R. [Univ. of Newcastle, Callaghan (Australia)

    1996-12-31

    A mechanistic study is detailed in which coal ash is heated with its shrinkage measured continuously up to a temperature of 1600{degrees}C. The temperatures corresponding to the rapid rate of shrinkage are shown to correspond to the formation of eutectics identified on phase diagrams. Samples were therefore heated to these temperatures, cooled rapidly and examined with an SEM to identify the associated chemical and physical changes. The progressive changes in the range of chemical analysis (from SEM), the extent of undissolved ash particles and porosity were then quantified and related to homogenization, viscosity and ash fusion mechanisms.

  15. Ash fusion temperatures and the transformations of coal ash particles to slag

    Energy Technology Data Exchange (ETDEWEB)

    Wall, T.F.; Creelman, R.A.; Gupta, R.; Gupta, S. [Univ. of Newcastle (Australia)

    1996-10-01

    A mechanistic study is detailed in which coal ash is heated with the shrinkage and electrical resistance measured continuously up to a temperature of 1600{degrees}C. The temperatures corresponding to rapid rates of shrinkage are shown to correspond to the formation of eutectics identified on phase diagrams. Samples where therefore heated to these temperatures, cooled rapidly and examined with an SEM to identify the associated chemical and physical changes. The progressive changes in the range of chemical analysis (from SEM), the extent of undissolved ash particles and porosity are then quantified and related to the shrinkage events and standard ash fusion temperatures.

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

    Energy Technology Data Exchange (ETDEWEB)

    Melchior, Tobias

    2011-10-26

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

  17. Measurement of gamma-dose caused by built in coal slags with elevated 226Ra concentration, and the modelling of shielding

    International Nuclear Information System (INIS)

    Nemeth, Cs.; Somlai, J.; Nenyei, A.; Skrinyar, M.; Kanyar, B.; Nemeth, P.; Hoffer, K.

    2000-01-01

    Slags, derived from coal mined in the neighbourhood of the town Tatabanya in Hungary, have been used as filling and insulating material for buildings of houses, block of flats, schools and kindergartens. The slag samples come from here have elevated concentrations of 226 Ra (range of 850 - 2400 Bq x kg -1 ). Therefore, the external gamma dose rates at 1 m height were about four times higher than the world average. It has been found, based on the modelling, that the dose rate could be decreased with 70 - 80% using an appropriate thickness of concrete or barite-concrete layers. (author)

  18. Experimental study on steam gasification of coal using molten blast furnace slag as heat carrier for producing hydrogen-enriched syngas

    International Nuclear Information System (INIS)

    Duan, Wenjun; Yu, Qingbo; Wu, Tianwei; Yang, Fan; Qin, Qin

    2016-01-01

    Highlights: • New method for producing HRG by gasification using BFS as heat carrier was proposed. • The continuous experiment of steam gasification in molten BFS was conducted. • The hydrogen-enriched syngas was produced by this method. • The molten BFS waste heat was utilized effectively by steam gasification. • This method could be widely used in steam gasification of different types of coal. - Abstract: The new method for producing hydrogen-enriched syngas (HRG) by steam gasification of coal using molten blast furnace slag (BFS) as heat carrier was established. In order to achieve the HRG production, a gasification system using this method was proposed and constructed. The carbon gasification efficiency (CE), hydrogen yield (YH_2) and cold gasification efficiency (CGE) in the molten slag reactor were measured, and the effects of temperature, S/C (steam to coal) ratio and coal type on the reaction performance were accessed. The results indicated that the preferred temperature was 1350 °C, which ensured the miscibility of coal–steam–slag, the diffusion of reactant in molten BFS as well as recovering waste heat. The optimal S/C ratio was 1.5–2.0 for producing HRG. Under these conditions, the hydrogen fraction was higher than 63% and the gas yield reached to 1.89 Nm"3/kg. The CE and CGE were higher than 96% and 102%, respectively. The YH_2 also reached to 1.20 Nm"3/kg. Meanwhile, different types of coal were successfully gasified in molten BFS reactor for producing HRG. The proposed method enhanced the gasification efficiency of different types of coal, recovered the BFS waste heat effectively, and had important guidance for industrial manufacture.

  19. Influence of a modification of the petcoke/coal ratio on the leachability of fly ash and slag produced from a large PCC power plant

    Energy Technology Data Exchange (ETDEWEB)

    Maria Izquierdo; Oriol Font; Natalia Moreno (and others) [CSIC, Barcelona (Spain). Institute of Earth Sciences ' Jaume Almera'

    2007-08-01

    Co-firing of coal with inexpensive secondary fuels such as petroleum coke is expected to increase in the near future in the EU given that it may provide certain economic and environmental benefits with respect to coal combustion. However, changes in the feed fuel composition of power plants may modify the bulk content and the speciation of a number of elements in fly ash and slag. Consequently, leachability of these byproducts also can be modified. This study is focused on identifying the changes in the environmental quality of co-fired fly ash and slag induced by a modification of the petcoke/coal ratio. Petcoke was found to increase the leachable content of V and Mo and to enhance the mobility of S and As. However, with the exception of these elements, the addition of this secondary fuel did not drastically modify the bulk composition or the overall leachability of the resulting fly ash and slag. 30 refs., 3 figs., 2 tabs.

  20. Power plant ash and slag waste management technological direction when Kansk-Achinsk brown coal is burned

    Directory of Open Access Journals (Sweden)

    Lihach Snejana A.

    2017-01-01

    Full Text Available Today resource efficiency technology development in all industries where conventional raw material is being replaced by local natural resources and industrial waste is an essential matter. Along with that most producing operations are overload with wide range of waste produced during technological process. Thermal power stations are real world evidence. Their main waste is ash and slag which accumulated in great amounts in often overfull ash dumps. The goal of present work is to find perspective ash dump waste utilization methods. The study will be based on experimentally obtained data: elementary compound and properties of Kansk-Achinsk brown coal. Research methods: experimental, chemical silicate analysis, mineralogical forms identification within samples by using ASM X-ray diffraction analysis. Experiments resulted with the following conclusions: silica is ash main component, and ash has the form of ore concentrate analogy in a number of elements. We think that ASM main properties which make it useful for utilization are: high content of calcium oxide; high ash sorption properties; ASM radiation safety class which makes them safe to be used in materials, goods, and structures production for residence and public buildings construction and reconstruction; sufficiently high content of individual elements.

  1. Cooling Effect Analysis of Suppressing Coal Spontaneous Ignition with Heat Pipe

    Science.gov (United States)

    Zhang, Yaping; Zhang, Shuanwei; Wang, Jianguo; Hao, Gaihong

    2018-05-01

    Suppression of spontaneous ignition of coal stockpiles was an important issue for safe utilization of coal. The large thermal energy from coal spontaneous ignition can be viewed as the latent energy source to further utilize for saving energy purpose. Heat pipe was the more promising way to diffuse effectively concentrated energy of the coal stockpile, so that retarding coal spontaneous combustion was therefore highly desirable. The cooling mechanism of the coal with heat pipe was pursued. Based on the research result, the thermal energy can be transported from the coal seam to the surface continuously with the use of heat pipe. Once installed the heat pipes will work automatically as long as the coal oxidation reaction was happened. The experiment was indicated that it can significantly spread the high temperature of the coal pile.

  2. A numerical model for chemical reaction on slag layer surface and slag layer behavior in entrained-flow gasifier

    Directory of Open Access Journals (Sweden)

    Liu Sheng

    2013-01-01

    Full Text Available The paper concerns with slag layer accumulation, chemical reaction on slag layer surface, and slag layer flow, heat and mass transfer on the wall of entrained-flow coal gasifier. A slag layer model is developed to simulate slag layer behaviors in the coal gasifier. This 3-D model can predict temperature, slag particle disposition rate, disposition particle composition, and syngas distribution in the gasifier hearth. The model is used to evaluate the effects of O2/coal ratio on slag layer behaviors.

  3. Dry cooling for coal fired power plants: the new state-of-the-art

    Energy Technology Data Exchange (ETDEWEB)

    Souvenir, C.; Nagel, P. [SPX Cooling Technologies (Belgium)

    2008-07-01

    In the first part of this paper an update is provided regarding the use of dry cooling in power plants. The evolution of the reasons leading to this technical solution, the trends in the market place, and the growth over the last 15 years are described. In the second part, the use of current advanced dry cooling technologies for coal-fired plants in China is illustrated. 34 figs.

  4. Analysis of the evaporative towers cooling system of a coal-fired power plant

    Directory of Open Access Journals (Sweden)

    Laković Mirjana S.

    2012-01-01

    Full Text Available The paper presents a theoretical analysis of the cooling system of a 110 MW coal-fired power plant located in central Serbia, where eight evaporative towers cool down the plant. An updated research on the evaporative tower cooling system has been carried out to show the theoretical analysis of the tower heat and mass balance, taking into account the sensible and latent heat exchanged during the processes which occur inside these towers. Power plants which are using wet cooling towers for cooling condenser cooling water have higher design temperature of cooling water, thus the designed condensing pressure is higher compared to plants with a once-through cooling system. Daily and seasonal changes further deteriorate energy efficiency of these plants, so it can be concluded that these plants have up to 5% less efficiency compared to systems with once-through cooling. The whole analysis permitted to evaluate the optimal conditions, as far as the operation of the towers is concerned, and to suggest an improvement of the plant. Since plant energy efficiency improvement has become a quite common issue today, the evaluation of the cooling system operation was conducted under the hypothesis of an increase in the plant overall energy efficiency due to low cost improvement in cooling tower system.

  5. Improvement of coal focus and cooling towers of COFRENTES NPP

    International Nuclear Information System (INIS)

    Martinez, I.; Bogh, P.

    1998-01-01

    Cofrentes Nuclear Power Plant is performing a improving program of its cooling towers based on the filling revamping and cooling water circuit improvement. Furthermore, and as consequence of the acquired experience on cooling towers due to the mentioned program, Cofrentes NPP has decided to follow up with this project from a different point of view based on the thermal-hydraulic optimization of the cooling process inside the towers. This program, which is going to be carried out by Cofrentes NPP, Iberinco and Energy Planning and Power Generation (EPPG) provides an improvement on the thermal profile and of the draught inside the cooling towers by improving the water distribution in the towers active area. In order to perform such a program is needed to fulfill a test program to assure a guaranteed performance gain. In this way, Iberinco is developing a test procedure which improves the results which are obtained with the present standards used commonly by the industry. As a consequence of this program, Cofrentes is expecting to obtain a gain of 5 to 8 MWe with a revenue period of 4 to 5 months, results validated in another foreigner Plant which have developed a similar program. (Author)

  6. Modular High Temperature Gas-Cooled Reactor heat source for coal conversion

    International Nuclear Information System (INIS)

    Schleicher, R.W. Jr.; Lewis, A.C.

    1992-09-01

    In the industrial nations, transportable fuels in the form of natural gas and petroleum derivatives constitute a primary energy source nearly equivalent to that consumed for generating electric power. Nations with large coal deposits have the option of coal conversion to meet their transportable fuel demands. But these processes themselves consume huge amounts of energy and produce undesirable combustion by-products. Therefore, this represents a major opportunity to apply nuclear energy for both the environmental and energy conservation reasons. Because the most desirable coal conversion processes take place at 800 degree C or higher, only the High Temperature Gas-Cooled Reactors (HTGRs) have the potential to be adapted to coal conversion processes. This report provides a discussion of this utilization of HTGR reactors

  7. Overview of Steel Slag Application and Utilization

    Directory of Open Access Journals (Sweden)

    Lim J.W.

    2016-01-01

    Full Text Available Significant quantities of steel slag are generated as waste material or byproduct every day from steel industries. Slag is produced from different types of furnaces with different operating conditions. Slag contains Ferrous Oxide, Calcium Oxide, Silica etc. Physical and chemical properties of slag are affected by different methods of slag solidification such as air cooled, steam, and injection of additives. Several material characterization methods, such as X-ray Diffraction (XRD, Scanned Electron Microscopy (SEM and Inductive Coupled Plasma (ICP-OES are used to determine elemental composition in the steel slag. Therefore, slags can become one of the promising materials in various applications such as in transportation industry, construction, cement production, waste water and water treatment. The various applications of steel slag indicate that it can be reused and utilized rather than being disposed to the landfill. This paper presents a review of its applications and utilization.

  8. Effect of Fe2O3 on the crystallization behavior of glass-ceramics produced from naturally cooled yellow phosphorus furnace slag

    Science.gov (United States)

    Liu, Hong-pan; Huang, Xiao-feng; Ma, Li-ping; Chen, Dan-li; Shang, Zhi-biao; Jiang, Ming

    2017-03-01

    CaO-Al2O3-SiO2 (CAS) glass-ceramics were prepared via a melting method using naturally cooled yellow phosphorus furnace slag as the main raw material. The effects of the addition of Fe2O3 on the crystallization behavior and properties of the prepared glass-ceramics were studied by differential thermal analysis, X-ray diffraction, and scanning electron microscopy. The crystallization activation energy was calculated using the modified Johnson-Mehl-Avrami equation. The results show that the intrinsic nucleating agent in the yellow phosphorus furnace slag could effectively promote the crystallization of CAS. The crystallization activation energy first increased and then decreased with increasing amount of added Fe2O3. At 4wt% of added Fe2O3, the crystallization activation energy reached a maximum of 676.374 kJ·mol-1. The type of the main crystalline phase did not change with the amount of added Fe2O3. The primary and secondary crystalline phases were identified as wollastonite (CaSiO3) and hedenbergite (CaFe(Si2O6)), respectively.

  9. Silicon liquid for cooling coal cutter loader motors

    Energy Technology Data Exchange (ETDEWEB)

    Donets, I K; Sukhanov, V V; Tsingarelli, E P; Dmitrenko, Yu I; Kovalev, E B

    1983-05-01

    Several silicones were tested with a view to their suitability for use as a cutter loader engine coolant. None were particularly toxic and FM-5.6AP had the best engineering properties; a full toxicological evaluation was therefore made of it. Threshold concentrations of FM-5.6AP were 450 and 24.1 mg/m/sup 3/ for the acute and chronic tests respectively. Increased temperature (120 C) did not affect the toxicity of the vapors significantly. No influence on the phagocytosis, deposition and elimination of coal dust in the lungs was found. Tests carried out underground in a Donbass mine revealed no harmful effects on miners. Laboratory and mine tests using an EhKVZh-315 cutter loader engine revealed that the quantity of FM-5.6AP vapor present in the air flow is less than the detectable minimum (0.01 mg/ml). It may therefore safely be used as a dielectric liquid in cutter loader engines.

  10. Thermodynamic evaluation of chemical looping combustion for combined cooling heating and power production driven by coal

    International Nuclear Information System (INIS)

    Fan, Junming; Hong, Hui; Zhu, Lin; Wang, Zefeng; Jin, Hongguang

    2017-01-01

    Highlights: • An ex-situ coal gasification chemical looping combustion integrated with CCHP process has been presented. • This novel process maintains a maximum energy efficiency of 60.34%. • The fossil energy saving ratio of this process is optimize to be 27.20%. - Abstract: This study carries out an investigation concerning on the benefits of ex-situ coal gasification chemical looping combustion integrated with combined cooling, heating and power generation (CCHP-CLC) by means of thermodynamic evaluation. The coal gasification syngas is introduced into chemical looping combustion for inherent separation of CO_2 without extra energy consumed. The combustion flue gases from both air reactor and fuel reactor are sequentially fed into gas turbines for electricity production, a heat recovery vapor generator unit for further electricity generation with driving a LiBr-H_2O absorption chiller for cooling production in summer and finally a heat exchanger for daily heat water production. A preliminary parameter analysis helps to obtain the optimum operating condition, as steam-to-coal ratio (S/C) of 0.05, oxygen-to-coal ratio (O/C) of 0.75, and operating pressure of chemical looping combustion process of 5 bar. The overall energy efficiency of the CCHP-CLC process is calculated equal to 58.20% in summer compared with that of 60.34% in winter. Importantly, by utilization of such process, the reduction potential of fossil fuel (coal) consumption has been demonstrated to be 23.36% in summer and 27.20% in winter.

  11. Slags from steel production: Properties and their utilization

    Directory of Open Access Journals (Sweden)

    J. Vlcek

    2013-07-01

    Full Text Available During steel production a considerable amount of slags is produced. In addition to its usual processing, as recycling in device for steel production and preparation of aggregates, it is also possible to apply less common slag processing ways. Depending on cooling mode of the steel slags these may show some binding properties. Geopolymer type binders can be prepared from the slag using alkali activators or the hydraulic properties of the dicalciumsilicate present in the slag can be induced by water. The paper summarizes present state of material utilisation of the steel slags with focus on emphasize of the possible sources of the slag volume instability. The influence of process of slag cooling on its phase composition is documented. It was also found that slags from real sources show different parameters compared to samples obtained for laboratory examination.

  12. performance of steel slag performance of steel slag as fine

    African Journals Online (AJOL)

    eobe

    Suitability of using steel slag (SS) as substitute for sand in concrete was ... The strength of SS concrete increased with increase in proporti. 10 mm. .... additives used. All other oxides ..... low lime coal fly ash in foamed concrete”, Fuel, Vol. 84,.

  13. Critical evaluation of high-temperature gas-cooled reactors applicable to coal conversion

    International Nuclear Information System (INIS)

    Spiewak, I.; Jones, J.E. Jr.; Rittenhouse, P.L.; DeStefano, J.R.; Delene, J.G.

    1975-12-01

    A critical review is presented of the technology and costs of very high-temperature gas-cooled reactors (VHTRs) applicable to nuclear coal conversion. Coal conversion processes suitable for coupling to reactors are described. Vendor concepts of the VHTR are summarized. The materials requirements as a function of process temperature in the range 1400 to 2000 0 F are analyzed. Components, environmental and safety factors, economics and nuclear fuel cycles are reviewed. It is concluded that process heat supply in the range 1400 to 1500 0 F could be developed with a high degree of assurance. Process heat at 1600 0 F would require considerably more materials development. While temperatures up to 2000 0 F appear to be attainable, considerably more research and risk were involved. A demonstration plant would be required as a step in the commercialization of the VHTR

  14. Geomechanical Analysis of Underground Coal Gasification Reactor Cool Down for Subsequent CO2 Storage

    Science.gov (United States)

    Sarhosis, Vasilis; Yang, Dongmin; Kempka, Thomas; Sheng, Yong

    2013-04-01

    Underground coal gasification (UCG) is an efficient method for the conversion of conventionally unmineable coal resources into energy and feedstock. If the UCG process is combined with the subsequent storage of process CO2 in the former UCG reactors, a near-zero carbon emission energy source can be realised. This study aims to present the development of a computational model to simulate the cooling process of UCG reactors in abandonment to decrease the initial high temperature of more than 400 °C to a level where extensive CO2 volume expansion due to temperature changes can be significantly reduced during the time of CO2 injection. Furthermore, we predict the cool down temperature conditions with and without water flushing. A state of the art coupled thermal-mechanical model was developed using the finite element software ABAQUS to predict the cavity growth and the resulting surface subsidence. In addition, the multi-physics computational software COMSOL was employed to simulate the cavity cool down process which is of uttermost relevance for CO2 storage in the former UCG reactors. For that purpose, we simulated fluid flow, thermal conduction as well as thermal convection processes between fluid (water and CO2) and solid represented by coal and surrounding rocks. Material properties for rocks and coal were obtained from extant literature sources and geomechanical testings which were carried out on samples derived from a prospective demonstration site in Bulgaria. The analysis of results showed that the numerical models developed allowed for the determination of the UCG reactor growth, roof spalling, surface subsidence and heat propagation during the UCG process and the subsequent CO2 storage. It is anticipated that the results of this study can support optimisation of the preparation procedure for CO2 storage in former UCG reactors. The proposed scheme was discussed so far, but not validated by a coupled numerical analysis and if proved to be applicable it could

  15. Studying the melting behavior of coal, biomass, and coal/biomass ash using viscosity and heated stage XRD data

    DEFF Research Database (Denmark)

    Arvelakis, Stelios; Folkedahl, B.; Dam-Johansen, Kim

    2006-01-01

    by the cocombustion tests appeared to be somewhat different compared to that of the laboratory-prepared ash samples. The heated stage XRD data provide useful information regarding the reactions among the various ash compounds and the phase transformations during the heating and cooling of the ash samples and helped...... a high-temperature rotational viscometer and a hot stage XRD. The produced data were used to calculate the operating temperature of a pilot-scale entrained flow reactor during the cocombustion of biomass/ coal samples in order to ensure the slag flow and to avoid corrosion of the walls due to liquid slag...

  16. Artificial neural network model to predict slag viscosity over a broad range of temperatures and slag compositions

    Energy Technology Data Exchange (ETDEWEB)

    Duchesne, Marc A. [Chemical and Biological Engineering Department, University of Ottawa, 161 Louis Pasteur, Ottawa, Ont. (Canada); CanmetENERGY, 1 Haanel Drive, Ottawa, Ontario (Canada); Macchi, Arturo [Chemical and Biological Engineering Department, University of Ottawa, 161 Louis Pasteur, Ottawa, Ont. (Canada); Lu, Dennis Y.; Hughes, Robin W.; McCalden, David; Anthony, Edward J. [CanmetENERGY, 1 Haanel Drive, Ottawa, Ontario (Canada)

    2010-08-15

    Threshold slag viscosity heuristics are often used for the initial assessment of coal gasification projects. Slag viscosity predictions are also required for advanced combustion and gasification models. Due to unsatisfactory performance of theoretical equations, an artificial neural network model was developed to predict slag viscosity over a broad range of temperatures and slag compositions. This model outperforms other slag viscosity models, resulting in an average error factor of 5.05 which is lower than the best obtained with other available models. Genesee coal ash viscosity predictions were made to investigate the effect of adding Canadian limestone and dolomite. The results indicate that magnesium in the fluxing agent provides a greater viscosity reduction than calcium for the threshold slag tapping temperature range. (author)

  17. ENERGY ASPECTS OF STEELMAKING SLAGS APPLICATION IN METALLURGY

    Directory of Open Access Journals (Sweden)

    V. L. Naydek

    2013-01-01

    Full Text Available A comparative assessment of energy intensity of converter steel production in different types of smelting with slag processing in the ladle was made. Analysis of the data shows that the use of liquid steel slag in steel production for its refining saves about 2.2 GJ or 75 kg of coal equivalent for each ton of metal.

  18. Low-Chrome/Chrome Free Refractories for Slagging Gasifiers

    International Nuclear Information System (INIS)

    Bennett, J.P.; Kwong, K.-S.; Powell, C.P.; Thomas, H.; Petty, A.V. Jr.

    2007-01-01

    Gasifiers are containment vessels used to react carbon-containing materials with oxygen and water, producing syngas (CO and H2) that is used in chemical and power production. It is also a potential source of H2 in a future hydrogen economy. Air cooled slagging gasifiers are one type of gasifier, operating at temperatures from 1275-1575 C and at pressures of 400 psi or higher. They typically use coal or petroleum coke as the carbon source, materials which contain ash impurities that liquefy at the gasification temperatures, producing liquid slag in quantities of 100 or more tons/day, depending on the carbon fed rate and the percent ash present in the feedstock. The molten slag is corrosive to refractory linings, causing chemical dissolution and spalling. The refractory lining is composed of chrome oxide, alumina, and zirconia; and is replaced every 3-24 months. Gasifier users would like greater on-line availability and reliability of gasifier liners, something that has impacted gasifier acceptance by industry. Research is underway at NETL to improve refractory service life and to develop a no-chrome or low-chrome oxide alternative refractory liner. Over 250 samples of no- or low-chrome oxide compositions have been evaluated for slag interactions by cup testing; with potential candidates for further studies including those with ZrO2, Al2O3, and MgO materials. The development of improved liner materials is necessary if technologies such as IGCC and DOE's Near Zero Emissions Advanced Fossil Fuel Power Plant are to be successful and move forward in the marketplace

  19. Facing slag glass and slag glass ceramic produced from thermal power plant ash

    Energy Technology Data Exchange (ETDEWEB)

    Buruchenko, A.E.; Kolesnikov, A.A.; Lukoyanov, A.G.

    1990-10-01

    Evaluates properties of fly ash and slags from the Krasnoyarsk coal-fired power plants and their utilization for glass and ceramic glass production. Composition of a mixture of fly ash and slag was: silica 40-55%, aluminium oxides 10-40%, ferric trioxide 6-14%, calcium oxides 20-35%, magnesium oxides 3-6%, potassium oxides 0.3-1.5%, sodium oxides 0.2-05%, sulfur trioxide 0.9-5.0%. The analyzed fly ash and slags from the Krasnoyarsk plant were an economic waste material for glass production. Properties of sand, clay and other materials used in glass production and properties of glass and ceramic glass produced on the basis of fly ash and slags are analyzed. Economic aspects of fly ash and slag utilization are also evaluated. 3 refs.

  20. An update on field test results for an engineered refractory for slagging gasifiers

    Energy Technology Data Exchange (ETDEWEB)

    Dogan, O.N.; Alman, D.E.; Jablonski, P.D.; Hawk, J.A.

    2006-05-01

    The widespread commercial adaptation of slagging gasifier technology to produce power, fuel, and/or chemicals from coal will depend in large measure on the technology’s ability to prove itself both economic and reliable. Improvements in gasifier reliability, availability, and maintainability will in part depend on the development of improved performance structural materials with longer service life in this application. Current generation refractory materials used to line the air-cooled, slagging gasifier vessel, and contain the gasification reaction, often last no more than three to 18 months in commercial applications. The downtime required for tear-out and replacement of these critical materials contributes to gasifier on-line availabilities that fall short of targeted goals. In this talk we will discuss the development of an improved refractory material engineered by the NETL for longer service life in this application, and provide an update on recent field test results.

  1. Determination of 210Pb by direct gamma-ray spectrometry, beta counting via 210Bi and alpha-particle spectrometry via 210Po in coal, slag and ash samples from thermal power plant

    International Nuclear Information System (INIS)

    Seslak, Bojan; Vukanac, Ivana; Kandic, Aleksandar; Durasevic, Mirjana; Eric, Milic; Jevremovic, Aleksandar

    2017-01-01

    In order to compare three different techniques and estimate radiological impact, activity concentration of 210 Pb in coal, slag and ash samples from thermal power plant 'Nikola Tesla', Serbia, were measured, and results are presented in this study. Determination of 210 Pb was carried out in three ways: using HPGe gamma spectrometer and via in-growth of 210 Po and 210 Bi by alpha-particle spectrometry and proportional counting, respectively. The results obtained for three different techniques were compared. Statistical analysis and comparison of methods were carried out by combination of Z score and χ 2 statistical tests. Tests results, as well as values of measured activities concentrations obtained by alpha and gamma spectrometry, showed that gamma spectrometry is a valid alternative to time-consuming alpha spectrometry for low level activity measurements of 210 Pb. This remark is also valid even for gamma spectrometers with poor efficiency in low energy region. (author)

  2. Coal

    International Nuclear Information System (INIS)

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

    2001-12-01

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

  3. Using mineralogy as a guide to understanding slagging: a case study

    Energy Technology Data Exchange (ETDEWEB)

    Creelman, R.A. [R.A. Creelman & Associates (Australia)

    1994-12-31

    This paper details the mineralogy that accompanied the Callide B Power station slagging investigations. Investigations were made of coal mineral matter, particles collected from the furnace, flyash and the slag deposits. Objectives were to characterise the particles formed from burning Callide coal, to relate them to the slag deposits and flyash, and by applying thermodynamics gain an understanding of the underlying mechanisms that lead to attachment and accumulation of particles in the furnace. 9 refs., 2 figs., 7 tabs.

  4. Glassy slag from rotary hearth vitrification

    International Nuclear Information System (INIS)

    Eschenbach, R.C.; Simpson, M.D.; Paulson, W.S.; Whitworth, C.G.

    1995-01-01

    Use of a Plasma Arc Centrifugal Treatment (PACT) system for treating mixed wastes containing significant quantities of soil results in formation of a glassy slag which melts at significantly higher temperatures than the borosilicate glasses. The slag typically contains mostly crystalline material, frequently in an amorphous matrix, thus the appellation open-quotes glassy slag.close quotes Details of the PACT process are given. The process will be used for treating buried wastes from Pit 9 at the Idaho National Engineering Laboratory and low-level mixed wastes from nuclear power plants in Switzerland. Properties of the slag after cooling to room temperature are reported, in particular the Product Consistency Test, for a number of different feedstocks. In almost all cases, the results compare favorably with conventional borosilicate glasses. In the PACT system, a transferred arc carries current from the plasma torch to a rotating molten bed of slag, which is the material being heated. Thus this transferred arc adds energy where it is needed - at and near the surface of the molten bath. Material is fed into the furnace through a sealed feeder, and falls into a rotating tub which is heated by the arc. Any organic material is quickly vaporized into the space above the slag bed and burned by the oxygen in the furnace. Metal oxides in the charge are melted into the slag. Metal in the feed tends to melt and collect as a separate phase underneath the slag, but can be oxidized if desired. When oxidized, it unites with other constituents forming a homogeneous slag

  5. Control of spontaneous combustion of coal in goaf at high geotemperatureby injecting liquid carbon dioxide: inertand cooling characteristics of coal

    Science.gov (United States)

    Liu, Zhenling; Wen, Hu; Yu, Zhijin; Wang, Chao; Ma, Li

    2018-02-01

    The spontaneous combustion of coal in goaf at high geo temperatures is threatening safety production in coalmine. The TG-DSC is employed to study the variation of mass and energy at 4 atmospheres (mixed gases of N2, O2 and CO2) and heating rates (10°C/min) during oxidation of coal samples. The apparent activation energy and pre-exponential factor of coal oxidation decrease rapidly with increasing theCO2 concentration. Furthermore, its reaction rate is slow, its heat released reduces. Based on the conditions of 1301 face in the Longgucoalmine, a three-dimensional geometry model is developed to simulate the distributions stream field and temperature field and the variation characteristics ofCO2 concentration field after injecting liquidCO2. The results indicate that oxygen reached to depths of˜120m in goaf, 100m in the side of inlet air, and 10m in the side of outlet air before injecting liquidCO2. After injecting liquidCO2for 28.8min, the width of oxidation and heat accumulation zone is shortened by 20m, and the distance is 80m in the side of working face and 40˜60m in goafin the direction of dip affected by temperature.

  6. Methanol from coal without CO2 production via the modular high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Schleicher, R.W. Jr.; Engler, D.; Labar, M.P.

    1992-01-01

    Displacement options for petroleum fuels include natural gas (compressed or liquified), synthetic gasoline, biomass fuels, electric vehicles, hydrogen, and methanol. This paper reports that although no alternative meets all the desired characteristics of economics, environmental impact, supply logistics, and vehicle technology, methanol has often been cited as a good compromise and is perhaps the best coal derived fuel. The main criticism leveled at methanol is whether it can be produced economically in sufficient quantities to significantly displace petroleum-derived fuels. Although methanol can be manufactured from biomass, natural gas or coal feedstocks, only coal offers the potential for a substantial long term indigenous U.S. feedstock

  7. Acidity of vapor plume from cooling tower mixed with flue gases emitted from coal-fired power plant.

    Science.gov (United States)

    Hlawiczka, Stanislaw; Korszun, Katarzyna; Fudala, Janina

    2016-06-01

    Acidity of products resulting from the reaction of flue gas components emitted from a coal-fired power plant with water contained in a vapor plume from a wet cooling tower was analyzed in a close vicinity of a power plant (710 m from the stack and 315 m from the cooling tower). Samples of this mixture were collected using a precipitation funnel where components of the mixed plumes were discharged from the atmosphere with the rainfall. To identify situations when the precipitation occurred at the same time as the wind directed the mixed vapor and flue gas plumes above the precipitation funnel, an ultrasound anemometer designed for 3D measurements of the wind field located near the funnel was used. Precipitation samples of extremely high acidity were identified - about 5% of samples collected during 12 months showed the acidity below pH=3 and the lowest recorded pH was 1.4. During the measurement period the value of pH characterizing the background acidity of the precipitation was about 6. The main outcome of this study was to demonstrate a very high, and so far completely underestimated, potential of occurrence of episodes of extremely acid depositions in the immediate vicinity of a coal-fired power plant. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. The comparative analysis of heat transfer efficiency in the conditions of formation of ash deposits in the boiler furnaces, with taking into account the crystallization of slag during combustion of coal and water-coal fuel

    Science.gov (United States)

    Salomatov, V. V.; Kuznetsov, G. V.; Syrodoy, S. V.

    2017-11-01

    The results of the numerical simulation of heat transfer from the combustion products of coal and coal-water fuels (CWF) to the internal environment. The mathematical simulation has been carried out on the sample of the pipe surfaces of the combustion chamber of the boiler unit. The change in the characteristics of heat transfer (change of thermochemical characteristics) in the conditions of formation of the ash deposits have been taken into account. According to the results of the numerical simulation, the comparative analysis of the efficiency of heat transfer has been carried out from the furnace environment to the inside pipe coolant (water, air, or water vapor) from the combustion of coal and coal-water fuels. It has been established that, in the initial period of the boiler unit operation during coal fuel combustion the efficiency of heat transfer from the combustion products of the internal environment is higher than when using CWF. The efficiency of heat transfer in CWF combustion conditions is more at large times (τ≥1.5 hours) of the boiler unit. A significant decrease in heat flux from the combustion products to the inside pipe coolant in the case of coal combustion compared to CWF has been found. It has been proved that this is due primarily to the fact that massive and strong ash deposits are formed during coal combustion.

  9. Processing of ash and slag waste of heating plants by arc plasma to produce construction materials and nanomodifiers

    Science.gov (United States)

    Buyantuev, S. L.; Urkhanova, L. A.; Kondratenko, A. S.; Shishulkin, S. Yu; Lkhasaranov, S. A.; Khmelev, A. B.

    2017-01-01

    The resultsare presented of plasma processing slag and ash waste from coal combustion in heating plants. Melting mechanism of ashand slagraw material is considered by an electromagnetic technological reactor. The analysis was conducted of temperature and phase transformations of raw material when it is heated up to the melting point, and also determination of specific energy consumption by using a generalized model of the thermodynamic analysis of TERRA. The study of materials melting temperature conditions and plum of melt was carried with high-temperature thermal imaging method, followed by mapping and 3D-modeling of the temperature fields. The investigations to establish the principal possibilities of using slag waste of local coal as raw material for the production of mineral (ash and slag) fibers found that by chemical composition there are oxides in the following ranges: 45-65% SiO2; 10-25% Al2O3; 10-45% CaO; 5-10% MgO; other minerals (less than 5%). Thus, these technological wastes are principally suitable for melts to produce mineral wool by the plasma method. An analysis of the results shows the melting point of ash and slag waste - 1800-2000 °C. In this case the specific energy consumption of these processes keeps within the limits of 1.1-1.3 kW*h/kg. For comparison it should be noted that the unit cost of electricity in the known high-melting industrial installations 5-6 kW*h/kg. Upon melting ash and slag waste, which contains up to 2-5% of unburned carbon, carbon nanomaterials were discovered.in the form of ultrafine soot accumulating as a plaque on the water-cooled surfaces in the gas cleaning chamber. The process of formation of soot consists in sublimation-desublimation of part of carbon which is in ash and slag, and graphite electrode. Thus, upon melting of ash and slag in the electromagnetic reactor it is possible to obtain melt, and in the subsequent mineral high quality fiber, which satisfies the requirements of normative documents, and

  10. Improving Beneficiation of Copper and Iron from Copper Slag by Modifying the Molten Copper Slag

    Directory of Open Access Journals (Sweden)

    Zhengqi Guo

    2016-04-01

    Full Text Available In the paper, a new technology was developed to improve the beneficiation of copper and iron components from copper slag, by modifying the molten slag to promote the mineralization of valuable minerals and to induce the growth of mineral grains. Various parameters, including binary basicity, dosage of compound additive, modification temperature, cooling rate and the end point temperature of slow cooling were investigated. Meanwhile, optical microscope, scanning electron microscope and energy dispersive spectrometer (SEM-EDS was employed to determine the mineralogy of the modified and unmodified slag, as well as to reveal the mechanisms of enhancing beneficiation. The results show that under the proper conditions, the copper grade of rougher copper concentrate was increased from 6.43% to 11.04%, iron recovery of magnetic separation was increased significantly from 32.40% to 63.26%, and other evaluation indexes were changed slightly, in comparison with unmodified copper slag. Moreover, matte and magnetite grains in the modified slag aggregated together and grew obviously to the mean size of over 50 μm, resulting in an improvement of beneficiation of copper and iron.

  11. Method of flash evaporation and condensation – heat pump for deep cooling of coal-fired power plant flue gas: Latent heat and water recovery

    International Nuclear Information System (INIS)

    Li, Yuzhong; Yan, Min; Zhang, Liqiang; Chen, Guifang; Cui, Lin; Song, Zhanlong; Chang, Jingcai; Ma, Chunyuan

    2016-01-01

    Highlights: • A method is developed for deep cooling of flue gas in coal-fired boilers. • The method can recover both latent heat and water from flue gas. • The method utilizes FGD scrubber as a deep cooling exchanger. • The method adopts the direct heat exchange mode to avoid the corrosion problem. - Abstract: Flue gas waste heat recovery and utilization is an efficient means to improve the energy efficiency of coal-fired power plants. At present, the surface corrosion and fouling problems of heat exchanger hinder the development of flue gas deep cooling. In this study, a novel flue gas deep cooling method that can reduce flue gas temperature below the dew point of vapor to recover latent heat and obtain clean water simultaneously is proposed to achieve improved energy efficiency. The heat transfer mode of this method is the direct contact mode, which takes the scrubber, e.g. the flue gas desulfurization (FGD) scrubber, as the deep cooling exchanger. The flash evaporation and condensation (FEC) device and heat pump (HP) are utilized to provide low-temperature medium, such as FGD slurry or water, for washing and deep cooling flue gas, to collect recovered water, and to absorb recovered waste heat. This method is called as the FEC–HP method. This paper elaborated on two optional models of the proposed method. The mechanism for recovering heat and water was also analyzed using the customized flue gas humidity chart, and the method to quantitate recovered heat and water, as well as the results of the case of a 300 MW coal-fired generator set were provided. Net present value calculations showed that this method is profitable in the scenario of burning high-water-content coals. Several potential advantages of this method and suggestions for practical application were also discussed.

  12. In situ observation of the role of alumina particles on the crystallization behavior of slags

    Energy Technology Data Exchange (ETDEWEB)

    Orrling, C.

    2000-09-01

    The confocal laser scanning microscope (CLSM) allows crystallization behavior in liquid slags to he observed in situ at high temperatures. Slags in the lime-silica-alumina-magnesia system are easily tinder cooled and it is possible to construct time temperature transformation (TTT) diagrams for this system. The presence of solid alumina particles its these liquid slags was studied to determine if these particles act as heterogeneous nucleation sites that cause she precipitation of solid material within slags. The introduction of alumina particles reduced the incubation time for the onset of crystallization and increased the temperature at which crystallization was observed in the slags to close to the liquidus temperature for the slag. Crystal growth rates are in a good agreement with Ivantsov's solution of the problem of diffusion controlled dendritic growth. Alumina appears to be a potent nucleating agent in the slag systems that were studied. (author)

  13. The chemical composition of tertiary Indian coal ash and its ...

    Indian Academy of Sciences (India)

    In Part 1 of the present investigation, 37 representative Eocene coal samples of Meghalaya, India were analyzed and their ... and trace elements present in coal may also affect ..... factors controlling clinker formation, slagging, and fouling in ...

  14. A Techno-Economic Assessment of Hybrid Cooling Systems for Coal- and Natural-Gas-Fired Power Plants with and without Carbon Capture and Storage.

    Science.gov (United States)

    Zhai, Haibo; Rubin, Edward S

    2016-04-05

    Advanced cooling systems can be deployed to enhance the resilience of thermoelectric power generation systems. This study developed and applied a new power plant modeling option for a hybrid cooling system at coal- or natural-gas-fired power plants with and without amine-based carbon capture and storage (CCS) systems. The results of the plant-level analyses show that the performance and cost of hybrid cooling systems are affected by a range of environmental, technical, and economic parameters. In general, when hot periods last the entire summer, the wet unit of a hybrid cooling system needs to share about 30% of the total plant cooling load in order to minimize the overall system cost. CCS deployment can lead to a significant increase in the water use of hybrid cooling systems, depending on the level of CO2 capture. Compared to wet cooling systems, widespread applications of hybrid cooling systems can substantially reduce water use in the electric power sector with only a moderate increase in the plant-level cost of electricity generation.

  15. Cleaning of a copper matte smelting slag from a water-jacket furnace by direct reduction of heavy metals.

    Science.gov (United States)

    Maweja, Kasonde; Mukongo, Tshikele; Mutombo, Ilunga

    2009-05-30

    Cleaning experiments of a copper matte smelting slag from the water-jacket furnace was undertaken by direct reduction in a laboratory-scale electric furnace. The effects of coal-to-slag ratio, w, and the reduction time, t, were considered for two different coal/slag mixing procedures. In the first procedure, metallurgical coal was added to the molten slag, whereas in the second procedure, coal was premixed with the solid slag before charging into the furnace. The recovery of heavy metals (Cu, Co), and the fuming of Pb and Zn were investigated. Contamination of the metal phase by iron and the acidity index of the final slag were analysed as these may impede the economical viability of the process. The lower w value of 2.56% yielded a recovery rate of less than 60% for copper and less than 50% for cobalt, and around 70% for zinc. However, increasing w to 5% allowed the recovery of 70-90% for Cu, Co and Zn simultaneously after 30-60 min reduction of the molten slag. After reduction, the cleaned slags contained only small amounts of copper and cobalt (zinc was efficient as the %Pb of the residual slag dropped to levels lower than 0.04% after 30 min of reduction. Ninety percent of the lead was removed from the initial slag and collected in the dusts. The zinc content of the cleaned slags quickly dropped to between 1 and 3 wt% from the initial 8.2% after 30 min reduction for w value of 5 and after 60 min reduction for w value of 2.56. The dusts contained about 60% Zn and 10% Pb. Recovery of lead from fuming of the slag was higher than 90% in all the experimental conditions considered in this study.

  16. Effect of fuel type and deposition surface temperature on the growth and structure of ash deposit collected during co-firing of coal with sewage-sludge, saw-dust and refuse derived fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kupka, Tomasz; Zajac, Krzysztof; Weber, Roman [Clausthal Univ. of Technology, Clausthal-Zellerfeld (Germany). Inst. of Energy Process Engineering and Fuel Technology

    2008-07-01

    Blends of a South African bituminous ''Middleburg'' coal and three alternative fuels (a municipal sewage-sludge, a saw-dust and a refuse derived fuel) have been fired in the slagging reactor to examine the effect of the added fuel on slagging propensity of the mixtures. Two kinds of deposition probes have been used, un-cooled ceramic probes and air-cooled steal probes. Distinct differences in physical and chemical structures of the deposits collected using the un-cooled ceramic probes and air-cooled metal probes have been observed. Glassy, easily molten deposits collected on un-cooled ceramic deposition probes were characteristic for co-firing of municipal sewage-sludge with coal. Porous, sintered (not molten) but easily removable deposits of the same fuel blend have been collected on the air-cooled metal deposition probes. Loose, easy removable deposits have been sampled on air-cooled metal deposition probe during co-firing of coal/saw-dust blends. The mass of the deposit sampled at lower surface temperatures (550-700 C) was always larger than the mass sampled at higher temperatures (1100-1300 C) since the higher temperature ash agglomerated and sintered much faster than the low temperature deposit. (orig.)

  17. Slag Treatment Followed by Acid Leaching as a Route to Solar-Grade Silicon

    NARCIS (Netherlands)

    Meteleva-Fischer, Y.V.; Yang, Y.; Boom, R.; Kraaijveld, B.; Kuntzel, H.

    2012-01-01

    Refining of metallurgical-grade silicon was studied using a process sequence of slag treatment, controlled cooling, and acid leaching. A slag of the Na2O-CaO-SiO2 system was used. The microstructure of grain boundaries in the treated silicon showed enhanced segregation of impurities, and the

  18. Report for fiscal 1993 by coal gasification committee; 1993 nendo sekitan gas ka iinkai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1984-03-01

    This report is a compilation mainly of distributed material. In the development of entrained bed coal gasification power generation, gasification is tested in a 2t/d-capable facility and gasification efficiency and operation characteristics are grasped, these constituting the studies of elements to assist pilot plant operation etc. The fluid temperature point of slag is found to decrease by 200 degrees C at the maximum upon addition of flux (CaO), and this improves on slag fluidity. For the development of a demonstration gas turbine, an experimentally built combustor is tested using a real gas. A combined cycle power system is studied by simulation. In the study of pilot plant operation, measures relative to slagging are implemented, inspection and maintenance are conducted for each facility, and the combustor for a demonstration plant is subjected to oil and coal combustion tests. In the study of a pilot plant for developing technologies for hydrogen production using coal, the plant stably runs more than 1,000 hours under 100% load at in a RUN-8-3 operation. Some deposit collects in the neighborhood of the contracted area of the blow nozzle and on some part in the slip stream, but it does not affect operation. No abnormalities are detected in the cyclone or heat recovery boiler. The pilot plant is let to continue its operation, and excellent results are achieved, which are beyond the targets of carbon conversion efficiency of 98% or higher and gas cooling efficiency of 78% or higher. (NEDO)

  19. Stabilization of carbon dioxide and chromium slag via carbonation.

    Science.gov (United States)

    Wu, Xingxing; Yu, Binbin; Xu, Wei; Fan, Zheng; Wu, Zucheng; Zhang, Huimin

    2017-08-01

    As the main greenhouse gas, CO 2 is considered as a threat in the context of global warming. Many available technologies to reduce CO 2 emission was about CO 2 separation from coal combustion and geological sequestration. However, how to deal with the cost-effective storage of CO 2 has become a new challenge. Moreover, chromium pollution, the treatment of which requires huge energy consumption, has attracted people's widespread attention. This study is aimed to develop the sequestration of CO 2 via chromium slag. A dynamic leaching experiment of chromium slag was designed to testify the ability of CO 2 adsorption onto chromium slag and to release Cr(VI) for stabilization. The results showed that the accumulative amounts of Cr(VI) were ca. 2.6 mg/g released from the chromium slag after 24 h of leaching. In addition, ca. 89 mg/g CO 2 was adsorbed by using pure CO 2 in the experiment at 12 h. Calcite is the only carbonate species in the post-carbonated slag analyzed by powder X-ray diffraction and thermal analysis. The approach provides the feasibility of the utilization of chromium slag and sequestration of the carbon dioxide at the same time at ordinary temperatures and pressures.

  20. Estimation of slagging in furnaces; Kuonaavuuden ennustaminen kivihiilen poelypoltossa

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, T; Jaeaeskelaeinen, K; Oeini, J; Koskiahde, A; Jokiniemi, J; Pyykkoenen, J [Imatran Voima Oy, Vantaa (Finland)

    1997-10-01

    Understanding and estimation of slagging in furnaces is essential in the design of new power plants with high steam values or in modifications like low-NO{sub x} retrofits in existing furnaces. Major slagging yields poor efficiency, difficult operation and high maintenance costs of the plant. The aim of the project is to develop a computational model for slagging in pulverized coal combustion. The model is based on Computer Controlled Scanning Electron Microscopy (CCSEM) analysis of mineral composition of the coal and physical models for behaviour of minerals inside a furnace. The analyzed mineral particles are classified to five composition classes and distributed to calculational coal particles if internal minerals of coal. The calculational coal particles and the external minerals are traced in the furnace to find out the behaviour of minerals inside the furnace. If the particle tracing indicates that the particle hits the heat transfer surface of the furnace the viscosity of the particle is determined to see if particle is sticky. The model will be implemented to 3D computational fluid dynamics based furnace simulation environment Ardemus which predicts the fluid dynamics, heat transfer and combustion in a furnace. (orig.)

  1. Heat Recovery from High Temperature Slags: A Review of Chemical Methods

    Directory of Open Access Journals (Sweden)

    Yongqi Sun

    2015-03-01

    Full Text Available Waste heat recovery from high temperature slags represents the latest potential way to remarkably reduce the energy consumption and CO2 emissions of the steel industry. The molten slags, in the temperature range of 1723–1923 K, carry large amounts of high quality energy. However, the heat recovery from slags faces several fundamental challenges, including their low thermal conductivity, inside crystallization, and discontinuous availability. During past decades, various chemical methods have been exploited and performed including methane reforming, coal and biomass gasification, and direct compositional modification and utilization of slags. These methods effectively meet the challenges mentioned before and help integrate the steel industry with other industrial sectors. During the heat recovery using chemical methods, slags can act as not only heat carriers but also as catalysts and reactants, which expands the field of utilization of slags. Fuel gas production using the waste heat accounts for the main R&D trend, through which the thermal heat in the slag could be transformed into high quality chemical energy in the fuel gas. Moreover, these chemical methods should be extended to an industrial scale to realize their commercial application, which is the only way by which the substantial energy in the slags could be extracted, i.e., amounting to 16 million tons of standard coal in China.

  2. Uranium in ancient slag from Rajasthan

    International Nuclear Information System (INIS)

    Pradeepkumar, T.B.; Fahmi, Sohail; Sharma, S.K.

    2008-01-01

    Anomalous radioactivity was recorded in two ancient slag dumps spread on the surface near Bansda (24 deg 35'N lat., 70 deg 09'E long.) and Dhavadiya (24 deg 30'N lat., 70 deg 05'E long.) villages, Udaipur District, Rajasthan. The slag, with a range of high to low radioactivity levels, is the remnant of ancient smelting in the area, probably for copper. Six samples showing low radioactivity in Bansda contain an average of 0.030% U 3 O 8 , while five moderately radioactive samples analysed contain 0.225% U 3 O 8 and four highly radioactive samples analysed contain 1.15% U 3 O 8 . The 15 samples contain on an average 0.627% copper, 719 ppm zinc, 329 ppm cobalt and 133 ppm vanadium. Fifteen samples from Dhavadiya slag assayed on an average contain 0.040% U 3 O 8 , 0.297% Cu, 292 ppm Zn and 250 ppm Co. The extent of crystallization seen in the slag is intriguing because an over-cooled melt generally forms glass. The high rate of crystal formation may be attributed to high amounts of volatiles, particularly CO 2 and SO 4 , released during the breakdown of limestone (added as flux during smelting) and sulphide minerals in the ore. The high order of radioactivity recorded in the slags of Bansda and Dhavadiya points to the presence of ore-grade uranium concentration associated with sulphide mineralization in the vicinity of the basement Banded Gneissic Complex, intrusive granites and the cover sequence of the Bhinder basin. (author)

  3. The leaching characteristics of vitrified slag

    International Nuclear Information System (INIS)

    Zhang, Jinlong; Li, Yaojian; Tian, Junguo; Sheng, Hongzhi; Xu, Yongxiang

    2010-01-01

    Full Text: Plasma-arc technology was developed to fix the heavy metal of flying ash by the Institute of Mechanics, Chinese Academy of Sciences (CAS-IMECH). A direct current (DC) experimental facility of 30 kW with plasma-arc technology was setup to form vitrified slag. The additives (CaO, SiO 2 ) were added into the reactor to form vitrified slag and fix the heavy metal (Cr, Pb), under dissimilar condition (long and short heating-up time, natural and water cooling). Vitrified slag was broken into different particle size, from 0.1 mm to 1 cm. The particles with different specific surface area were used to study the leaching of heavy metals in vitrified slag rate of speed. The pH value of leaching solution are from 2 to 12, the experiment was kept at different external temperature, from 4 degree Celsius to 70 degree celsius, for 1 week to 1 month. Heavy metal leaching concentration was used to measure the chemical stability of vitrified slag. The results show that the higher specific surface area, the higher heavy metal leaching concentration, but when the specific surface area reaches a certain value, little change in leaching concentration. The impact of temperature on leaching concentration was not significant, from 4 degree Celsius to 70 degree Celsius. The leaching concentration increases with decreasing of the pH value of leaching solution when the pH value of leaching solution less than 7, and little change in concentration increases with pH value when the pH value of leaching solution more than 7. Compared with the leaching concentration after 1 month, the leaching concentration after 1 week has not changed significantly. (Author)

  4. Mineral conversion and microstructure change in the melting process of Shenmu coal ash

    Energy Technology Data Exchange (ETDEWEB)

    Yang Jianguo; Deng Furong; Zhao Hong; Cen Kefa [Zhejiang University, Hangzhou (China). State Key Laboratory of Clean Energy Utilization

    2007-05-15

    China has rich reserves of Shenmu coal, which has the typical characteristic of low-melting-point ash. If used in the pulverized-coal boiler of a power plant, Shenmu coal would cause serious slagging. In order to solve the slagging problem of Shenmu coal, the melting mechanism of Shenmu coal ash was studied. One of the Shenmu coals - Wenjialiang coal - was selected for the study. Using thermogravimetry-differential scanning colorimetry (TG-DSC) methods, the change of the coal ash's physicochemistry with temperature was studied. The typical temperature points in the melting process were obtained. Ash samples of the different temperature points were prepared in a high-temperature furnace with parameters similar to those used in the TG-DSC test, and were then cooled quickly in water. Later, the ash samples were analyzed using X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX) methods in detail. Wenjialiang coal ash started to melt at 980{sup o}C. The ash was found to melt to a great extent at 1200{sup o}C and formed a multiform microstructure. At 1260{sup o}C, it was found to melt into a dense body with many pores, and formed a piece of vitreous body at 1340{sup o}C. Anorthite and gehlenite are the intermediate products that exist between 980 and 1340{sup o}C. They may be the main cause of the ash having low melting points, so that they could convert into a eutectic at low temperatures.

  5. Computational Fluid Dynamic Modeling of Zinc Slag Fuming Process in Top-Submerged Lance Smelting Furnace

    Science.gov (United States)

    Huda, Nazmul; Naser, Jamal; Brooks, Geoffrey; Reuter, Markus A.; Matusewicz, Robert W.

    2012-02-01

    Slag fuming is a reductive treatment process for molten zinciferous slags for extracting zinc in the form of metal vapor by injecting or adding a reductant source such as pulverized coal or lump coal and natural gas. A computational fluid dynamic (CFD) model was developed to study the zinc slag fuming process from imperial smelting furnace (ISF) slag in a top-submerged lance furnace and to investigate the details of fluid flow, reaction kinetics, and heat transfer in the furnace. The model integrates combustion phenomena and chemical reactions with the heat, mass, and momentum interfacial interaction between the phases present in the system. A commercial CFD package AVL Fire 2009.2 (AVL, Graz, Austria) coupled with a number of user-defined subroutines in FORTRAN programming language were used to develop the model. The model is based on three-dimensional (3-D) Eulerian multiphase flow approach, and it predicts the velocity and temperature field of the molten slag bath, generated turbulence, and vortex and plume shape at the lance tip. The model also predicts the mass fractions of slag and gaseous components inside the furnace. The model predicted that the percent of ZnO in the slag bath decreases linearly with time and is consistent broadly with the experimental data. The zinc fuming rate from the slag bath predicted by the model was validated through macrostep validation process against the experimental study of Waladan et al. The model results predicted that the rate of ZnO reduction is controlled by the mass transfer of ZnO from the bulk slag to slag-gas interface and rate of gas-carbon reaction for the specified simulation time studied. Although the model is based on zinc slag fuming, the basic approach could be expanded or applied for the CFD analysis of analogous systems.

  6. Internet Based, GIS Catalog of Non-Traditional Sources of Cooling Water for Use at America's Coal-Fired Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    J. Daniel Arthur

    2011-09-30

    In recent years, rising populations and regional droughts have caused coal-fired power plants to temporarily curtail or cease production due to a lack of available water for cooling. In addition, concerns about the availability of adequate supplies of cooling water have resulted in cancellation of plans to build much-needed new power plants. These issues, coupled with concern over the possible impacts of global climate change, have caused industry and community planners to seek alternate sources of water to supplement or replace existing supplies. The Department of Energy, through the National Energy Technology Laboratory (NETL) is researching ways to reduce the water demands of coal-fired power plants. As part of the NETL Program, ALL Consulting developed an internet-based Catalog of potential alternative sources of cooling water. The Catalog identifies alternative sources of water, such as mine discharge water, oil and gas produced water, saline aquifers, and publicly owned treatment works (POTWs), which could be used to supplement or replace existing surface water sources. This report provides an overview of the Catalog, and examines the benefits and challenges of using these alternative water sources for cooling water.

  7. A discussion on improving hydration activity of steel slag by altering its mineral compositions.

    Science.gov (United States)

    Wang, Qiang; Yan, Peiyu; Feng, Jianwen

    2011-02-28

    This study aims to investigate the ways to improve the cementitious properties of steel slag. The results show that the cementitious phase of steel slag is composed of silicate and aluminate, but the large particles of these phases make a very small contribution to the cementitious properties of steel slag. RO phase (CaO-FeO-MnO-MgO solid solution), Fe(3)O(4), C(2)F and f-CaO make no contribution to the cementitious properties of steel slag. A new kind of steel slag with more cementitious phase and less RO phase can be obtained by removing some large particles. This new steel slag possesses better cementitious properties than the original steel slag. The large particles can be used as fine aggregates for concrete. Adding regulating agent high in CaO and SiO(2) during manufacturing process of steel slag to increase the cementitious phase to inert phase ratio is another way to improve its cementitious properties. The regulating agent should be selected to adapt to the specific steel slag and the alkalinity should be increased as high as possible on the premise that the f-CaO content does not increase. The cooling rate should be enhanced to improve the hydration activity of the cementitious phase at the early ages and the grindability of steel slag. Copyright © 2010 Elsevier B.V. All rights reserved.

  8. Partitioning of heavy metals in a soil contaminated by slag: A redistribution study

    International Nuclear Information System (INIS)

    Bunzl, K.; Trautmannsheimer, M.; Schramel, P.

    1999-01-01

    In order to interpret reasonably the partitioning of heavy metals in a contaminated soil as observed from applying a sequential extraction procedure, information on possible redistribution processes of the metals during the various extraction steps is essential. For this purpose, sequential extraction was used to study the chemical partitioning of Ag, Cu, Ni, Pb, and Zn in a soil contaminated wither by a slag from coal firing or by a slag from pyrite roasting. Through additional application of sequential extraction to the pure slags as well as to the uncontaminated soil, it was shown that during the various extraction steps applied to the soil/slag mixtures, substantial redistribution processes of the metals between the slag- and soil particles can occur. In many cases, metals ions released during the extraction with acid hydroxylamine or acid hydrogen peroxide are partially readsorbed by solid constituents of the mixture and will therefore be found in the subsequent fractions extracted. As a result, one has to realize that (1) it will be difficult to predict the chemical partitioning of these metals in contaminated soils by investigating pure slags only, and (2) information on the partitioning of a metal in a slag contaminated soil will not necessarily give any relevant information on the form of this metal in the slag or in the slag/soil mixture, because the redistribution processes during sequential extraction will not be the same as those occurring in the soil solution under natural conditions

  9. Small, modular, low-cost coal-fired power plants for the international market

    Energy Technology Data Exchange (ETDEWEB)

    Zauderer, B.; Frain, B.; Borck, B. [Coal Tech Corp., Merion Station, PA (United States); Baldwin, A.L. [Dept. of Energy, Pittsburgh, PA (United States). Pittsburgh Energy Technology Center

    1997-12-31

    This paper presents recent operating results of Coal Tech`s second generation, air cooled, slagging coal combustor, and its application to power plants in the 1 to 20 MW range. This 20 MMBtu/hour combustor was installed in a new demonstration plant in Philadelphia, PA in 1995. It contains the combustion components of a 1 MWe coal fired power plant, a 17,500 lb/hour steam boiler, coal storage and feed components, and stack gas cleanup components. The plant`s design incorporates improvements resulting from 2,000 hours of testing between 1987 and 1993 on a first generation, commercial scale, air cooled combustor of equal thermal rating. Since operations began in early 1996, a total of 51 days of testing have been successfully completed. Major results include durability of the combustor`s refractory wall, excellent combustion with high ash concentration in the fuel, removal of 95% to 100% of the slag in the combustor, very little ash deposition in the boiler, major reduction of in-plant parasitic power, and simplified power system control through the use of modular designs of sub-systems and computer control. Rapid fuel switching between oil, gas, and coal and turndown of up to a factor of three was accomplished. All these features have been incorporated in advanced coal fired plant designs in the 1 to 20 MWe range. Incremental capital costs are only $100 to $200/kW higher than comparable rated gas or oil fired steam generating systems. Most of its components and subsystems can be factory assembled for very rapid field installation. The low capital, low operating costs, fuel flexibility, and compatibility with very high ash fuels, make this power system very attractive in regions of the world having domestic supplies of these fuels.

  10. Slag recycling of irradiated vanadium

    International Nuclear Information System (INIS)

    Gorman, P.K.

    1995-01-01

    An experimental inductoslag apparatus to recycle irradiated vanadium was fabricated and tested. An experimental electroslag apparatus was also used to test possible slags. The testing was carried out with slag materials that were fabricated along with impurity bearing vanadium samples. Results obtained include computer simulated thermochemical calculations and experimentally determined removal efficiencies of the transmutation impurities. Analyses of the samples before and after testing were carried out to determine if the slag did indeed remove the transmutation impurities from the irradiated vanadium

  11. Preparation and combustion of coal-water fuel from the Sin Pun coal deposit, southern Thailand

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-05-01

    In response to an inquiry by the Department of Mineral Resources in Thailand, the Energy & Environmental Research Center (EERC) prepared a program to assess the responsiveness of Sin Pun lignite to the temperature and pressure conditions of hot-water drying. The results indicate that drying made several improvements in the coal, notably increases in heating value and carbon content and reductions in equilibrium moisture and oxygen content. The equilibrium moisture content decreased from 27 wt% for the raw coal to about 15 wt% for the hot-water-dried (HWD) coals. The energy density for a pumpable coal-water fuel (CWF) indicates an increase from 4500 to 6100 Btu/lb by hot-water drying. Approximately 650 lb of HWD Sin Pun CWF were fired in the EERC`s combustion test facility. The fuel burned extremely well, with no feed problems noted during the course of the test. Fouling and slagging deposits each indicated a very low rate of ash deposition, with only a dusty layer formed on the cooled metal surfaces. The combustor was operated at between 20% and 25% excess air, resulting in a flue gas SO{sub 2} concentration averaging approximately 6500 parts per million.

  12. Report for fiscal 1994 by gasification technology subcommittee, Coal Gasification Committee; 1994 nendo sekitan gas ka iinkai gas ka gijutsu bukai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    As the result of a RUN-9 operation in the research on technologies for hydrogen production from coal and for pilot plants, it is found that the Muswellbrook, Datong, and Blair Athol coals are all suitable for gasification in pilot plants. Their handlability is considerably improved when the grain sizes after crushing are allowed to remain coarse (with the Blair Athol coal still retaining some disadvantage). A concept design is prepared for a HYCOL (hydrogen from coal) process demonstration plant. The reference coal is an imported coal similar to the Taiheiyo coal, and the hydrogen production target is set at 1-million m{sup 3}N/d (590t/d in terms of Taiheiyo coal) and hydrogen purity at 95% or higher. The whole process consists of coal gasification (with oxygen serving as gasification agent), dedusting, conversion to CO, desulfurization and decarboxylation (recovery of sulfur), and methanation. The gasification furnace is a 1-chamber entrained bed type with a 2-stage gyration flow. Dried and pulverized coal is conveyed aboard an air flow into the gasification furnace, where it is thrown into partial combustion reaction with the gasification agent for gasification in a high-temperature zone (1,500-1,600 degrees C), and the ash is taken out as slag. The generated gas is cooled in a heat recovery boiler, dedusted in a cyclone dust filter, and then forwarded to the washing unit. (NEDO)

  13. Low-rank coal research

    Energy Technology Data Exchange (ETDEWEB)

    Weber, G. F.; Laudal, D. L.

    1989-01-01

    This work is a compilation of reports on ongoing research at the University of North Dakota. Topics include: Control Technology and Coal Preparation Research (SO{sub x}/NO{sub x} control, waste management), Advanced Research and Technology Development (turbine combustion phenomena, combustion inorganic transformation, coal/char reactivity, liquefaction reactivity of low-rank coals, gasification ash and slag characterization, fine particulate emissions), Combustion Research (fluidized bed combustion, beneficiation of low-rank coals, combustion characterization of low-rank coal fuels, diesel utilization of low-rank coals), Liquefaction Research (low-rank coal direct liquefaction), and Gasification Research (hydrogen production from low-rank coals, advanced wastewater treatment, mild gasification, color and residual COD removal from Synfuel wastewaters, Great Plains Gasification Plant, gasifier optimization).

  14. Pyrochemical recovery of plutonium from calcium fluoride reduction slag

    Science.gov (United States)

    Christensen, D.C.

    A pyrochemical method of recovering finely dispersed plutonium metal from calcium fluoride reduction slag is claimed. The plutonium-bearing slag is crushed and melted in the presence of at least an equimolar amount of calcium chloride and a few percent metallic calcium. The calcium chloride reduces the melting point and thereby decreases the viscosity of the molten mixture. The calcium reduces any oxidized plutonium in the mixture and also causes the dispersed plutonium metal to coalesce and settle out as a separate metallic phase at the bottom of the reaction vessel. Upon cooling the mixture to room temperature, the solid plutonium can be cleanly separated from the overlying solid slag, with an average recovery yield on the order of 96 percent.

  15. Evaluation of the suitability of tin slag in cementitious materials: Mechanical properties and Leaching behaviour

    Science.gov (United States)

    Rustandi, Andi; Wafa' Nawawi, Fuad; Pratesa, Yudha; Cahyadi, Agung

    2018-01-01

    Tin slag, a by-product of tin production has been used in cementitious application. The present investigation focuses on the suitability of tin slag as primary component in cement and as component that substitute some amount of Portland Cement. The tin slags studied were taken from Bangka, Indonesia. The main contents of the tin slag are SiO2, Al2O3, and Fe2O3 according to the XRF investigation. The aim of this article was to study the mechanical behaviour (compressive strength), microstructure and leaching behaviour of tin slag blended cement. This study used air-cooled tin slag that had been passed through 400# sieve to replace Portland Cement with ratio 0, 10, 20, 30, 40 by weight. Cement pastes and tin slag blended cement pastes were prepared by using water/cement ratio (W/C) of 0.40 by weight and hydrated for various curing ages of 3, 7, 14 days The microstructure of the raw tin slag was investigated using Scanning Electron Microscope (SEM). The phase composition of each cement paste was investigated using X-ray Diffraction (XRD). The aim of the leachability test was to investigate the environmental impacts of tin slag blended cement product in the range 4-8 pH by using static pH-dependent leaching test. The result show that the increase of the tin slag content decreasing the mortar compressive strength at early ages. The use of tin slag in cement provide economic benefits for all related industries.

  16. Numerical simulations of slagging dynamics using a meshmeshless strategy

    Energy Technology Data Exchange (ETDEWEB)

    Losurdo, M.; Spliethoff, H. [Technische Universitaet Muenchen (Germany). Lehrstuhl fuer Energiesysteme

    2009-07-01

    In pulverized co-firing and gasification facilities such as coal and biomass power plants, ash deposition, fouling and slagging, may significantly affect heat exchange and gasification per-formance Deposit growth dramatically increases production loss and may lead to the shut-down of the facility. Computational Fluid Dynamics (CFD) calculations can be used as a valid 'non-intrusive' investigation tool in an efficient problem solving strategy. At TU Munich, an ongoing project aims to develop a dedicated numerical tool to monitor and predict deposition, deposit growth and slagging dynamics in pulverized solid fuel furnaces and gasifiers. A novel in-house code was developed to track solid particles and predict deposit growth and slag dynamics. The adopted numerical strategy uses a Mesh-Meshless approach combined with a Lagrangian particle tracking. Ash particles are tracked in a Lagrangian frame post-processing CFD gas phase results (RANS or LES). Growth and thermo-mechanical proper-ties of the deposit are simultaneously evaluated. Slag dynamics is computed by using a meshless approach: deposit mesh nodes are considered point-mass particles interacting only with mesh connected node-particle neighbours. Forces are modelled applying a visco-elastic model and calculated by means of a Galerking weight (kernel) function. The final goal is to mathematically describe both particle adhesion and slag dynamics applying visco-elastic models using a mesh-meshless approach aiming to investigate slag/slurry dynamics. Pre-liminary numerical results on one layer encourage further development on this subject. (orig.)

  17. Superconducting magnetic separation of ground steel slag powder for recovery of resources

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, H. W.; Kim, J. J.; Kim, Young Hun [Andong National University, Andong (Korea, Republic of); Ha, D. W. [Korea Electrotechnology Research Institute, Changwon (Korea, Republic of); Choi, J. H. [Dept. of Environmental Engineering, Catholic University of Pusan, Pusan (Korea, Republic of)

    2017-03-15

    Steel slag has been considered as an industrial waste. A huge amount of slag is produced as a byproduct and the steel slag usually has been dumped in a landfill site. However the steel slag contains valuable resources such as iron, copper, manganese, and magnesium. Superconducting magnetic separation has been applied on recovery of the valuable resources from the steel slag and this process also has intended to reduce the waste to be dumped. Cryo-cooled Nb-Ti superconducting magnet with 100 mm bore and 600 mm of height was used as the magnetic separator. The separating efficiency was evaluated in the function of magnetic field. A steel slag was ground and analyzed for the composition. Iron containing minerals were successfully concentrated from less iron containing portion. The separation efficiency was highly dependent on the particle size giving higher separating efficiency with finer particle. The magnetic field also effects on the separation ratio. Current study showed that an appropriate grinding of slag and magnetic separation lead to the recovery of metal resources from steel slag waste rather than dumping all of the volume.

  18. Question of the possibility of using diphenyl trichloride for cooling the electric motors of coal cutters loaders

    Energy Technology Data Exchange (ETDEWEB)

    Dmitrenko, Yu I; Donets, I K; Kovalev, Ye B; Sukhanov, V V; Tsingarelli, Ye P

    1981-01-01

    Studies showed that phenyl trichloride with its dielectric and explosive and fire safety properties may be used for cooling explosion protected cutter loader electric motors used in electric machine building.

  19. ECOLOGICAL AND TECHNOLOGYCAL ASPECTS OF ASH AND SLAG WASTES UTILIZATION

    Directory of Open Access Journals (Sweden)

    Tatyana Aleksandrova

    2017-07-01

    Full Text Available The article presents the results of investigation focused on the utilization of ash and slag wastes (ASW in Russia including investigation of chemical and physical properties of ASW and processing products. Many factors influence the technological properties of ash and slag materials: naturals, processes and environments. The integrated treatment of ash and slag wastes of both stored and re-formed types will allow obtaining the following commercial products: coal concentrate, iron concentrate, aluminosilicate cenospheres, aluminosilicate product. In this study we have analyzed the methods for separation of ASW iron-containing part using the different types of the magnetic separation from the ash and slag material from one of the combined heat and power plant (CHPP in the Russian Far East Federal District. The greatest interest is the dry magnetic separation with travelling electromagnetic field. The subject of research was a sample taken from one of ash dump of CHPP in the Far East. In the study iron concentrate containing Fetotal = 64% was obtained recovery 68% in the low intensity (up to 5 kOe travelling magnetic field.

  20. Plant concept of heat utilization of high temperature gas-cooled reactors. Co-generation and coal-gasification

    International Nuclear Information System (INIS)

    Tonogouchi, M.; Maeda, S.; Ide, A.

    1996-01-01

    In Japan, JAERI is now constructing the High temperature Engineering Test Reactor (HTTR) and the new era is coming for the development and utilization of HTR. Recognizing that the heat utilization of HTR would mitigate problems of environment and resources and contribute the effective use and steady supply of the energy, FAPIG organized a working group named 'HTR-HUC' to study the heat utilization of HTR in the field other than electric power generation. We chose three kinds of plants to study, 1) a co-generation plant in which the existing power units supplying steam and electricity can be replaced by a nuclear plant, 2) Coal gasification plant which can accelerate the clean use of coal and contribute stable supply of the energy and preservation of the environment in the world and 3) Hydrogen production plant which can help to break off the use of the new energy carrier HYDROGEN and will release people from the dependence of fossil energy. In this paper the former two plants, Co-generation chemical plant and Coal-gasification plant are focussed on. The main features, process flow and safety assessment of these plants are discussed. (J.P.N.)

  1. Reuse of Treated Internal or External Wastewaters in the Cooling Systems of Coal-Based Thermoelectric Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Radisav Vidic; David Dzombak; Ming-Kai Hsieh; Heng Li; Shih-Hsiang Chien; Yinghua Feng; Indranil Chowdhury; Jason Monnell

    2009-06-30

    This study evaluated the feasibility of using three impaired waters - secondary treated municipal wastewater, passively treated abandoned mine drainage (AMD), and effluent from ash sedimentation ponds at power plants - for use as makeup water in recirculating cooling water systems at thermoelectric power plants. The evaluation included assessment of water availability based on proximity and relevant regulations as well as feasibility of managing cooling water quality with traditional chemical management schemes. Options for chemical treatment to prevent corrosion, scaling, and biofouling were identified through review of current practices, and were tested at bench and pilot-scale. Secondary treated wastewater is the most widely available impaired water that can serve as a reliable source of cooling water makeup. There are no federal regulations specifically related to impaired water reuse but a number of states have introduced regulations with primary focus on water aerosol 'drift' emitted from cooling towers, which has the potential to contain elevated concentrations of chemicals and microorganisms and may pose health risk to the public. It was determined that corrosion, scaling, and biofouling can be controlled adequately in cooling systems using secondary treated municipal wastewater at 4-6 cycles of concentration. The high concentration of dissolved solids in treated AMD rendered difficulties in scaling inhibition and requires more comprehensive pretreatment and scaling controls. Addition of appropriate chemicals can adequately control corrosion, scaling and biological growth in ash transport water, which typically has the best water quality among the three waters evaluated in this study. The high TDS in the blowdown from pilot-scale testing units with both passively treated mine drainage and secondary treated municipal wastewater and the high sulfate concentration in the mine drainage blowdown water were identified as the main challenges for blowdown

  2. Effects of a reducer type on copper flash smelting slag decopperisation

    Directory of Open Access Journals (Sweden)

    B. Oleksiak

    2015-01-01

    Full Text Available In the paper, results of investigations on coke dust, anthracite dust and coal flotation concentrate application in the technology of copper flash smelting slag processing are presented. The results show that the selected reducers can be used as substitutes for the conventional coke.

  3. Alkali based slagging: a case study from Leigh Creek

    Energy Technology Data Exchange (ETDEWEB)

    R.A. Creelman; J. Bamberry; L.A. Juniper; C. Ward [University of Western Sydney, Penrith South, NSW (Australia)

    2003-07-01

    A systematic study was undertaken at NRG Port Augusta Power station in South Australia to determine the cause of ash deposition (slagging) in the boilers. Conventional wisdom suggests that iron in the ash is generally a major player in furnace ash deposition; however, mineralogical and chemical analyses of the deposits showed that the binding phase was plagioclase feldspar, dominated by the sodic feldspar albite. The study resulted in recognition that the cause of the formation of ash deposits in the North Flinders furnaces was the result of the ingestion of sodium and calcium into the melt that bound the deposits. This finding was a breakthrough in understanding the deposition process within these furnaces, and emphasises that not all slagging is iron related and that systematic studies of deposits, coal and ash make fundamental contributions to understanding the ash deposition mechanisms. 9 refs., 5 figs., 2 tabs.

  4. Slag-based saltstone formulations

    International Nuclear Information System (INIS)

    Langton, C.A.

    1987-01-01

    Approximately 400 x 10 6 liters of low-level alkaline salt solution will be treated at the Savannah River Plant (SRP) Defense Waste Processing Facility (DWPF) prior to disposal in concrete vaults at SRP. Treatment involves removal of CS + and Sr +2 followed by solidification and stabilization of potential contaminants in saltstone, a hydrated ceramic waste form. Chromium, technetium, and nitrate releases from saltstone can be significantly reduced by substituting hydraulic blast furnace slag for portland cement in the formulation designs. Slag-based mixes are also compatible with Class F fly ash used in saltstone as a functional extender to control heat of hydration and reduce permeability. A monolithic waste form is produced by the hydration of the slag and fly ash. Soluble ion release (NO 3 - ) is controlled by the saltstone microstructure. Chromium and technetium are less leachable from slag mixes compared to cement-based waste forms because these species are chemically reduced to a lower valence state by ferrous iron in the slag and precipitated as relatively insoluble phases, such as CR(OH) 3 and TcO 2 . 5 refs., 4 figs., 4 tabs

  5. Slag-based saltstone formulations

    International Nuclear Information System (INIS)

    Langton, C.A.

    1987-08-01

    Approximately 400 x 10 6 L of low-level alkaline salt solution will be treated at the Savannah River Plant (SRP) Defense Waste Processing Facility (DWPF) prior to disposal in concrete vaults at SRP. Treatment involves removal of Cs + and Sr +2 , followed by solidification and stabilization of potential contaminants in saltstone, a hydrated ceramic wasteform. Chromium, technetium, and nitrate releases from saltstone can be significantly reduced by substituting hydraulic blast furnace slag for portland cement in the formulation designs. Slag-based mixes are also compatible with the Class F flyash used in saltstone as a functional extender to control heat of hydration and reduce permeability. (Class F flyash is also locally available at SRP.) A monolithic wasteform is produced by the hydration of the slag and flyash. Soluble ion release (NO 3- ) is controlled by the saltstone microstructure. Chromium and technetium are less leachable from slag mixes because these species are chemically reduced to a lower valence state by ferrous iron in the slag and are precipitated as relatively insoluble phases, such as Cr(OH) 3 and TcO 2 . 3 refs., 3 figs., 2 tabs

  6. A Synergistic Combination of Advanced Separation and Chemical Scale Inhibitor Technologies for Efficient Use of Imparied Water As Cooling Water in Coal-based Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Jasbir Gill

    2010-08-30

    Nalco Company is partnering with Argonne National Laboratory (ANL) in this project to jointly develop advanced scale control technologies that will provide cost-effective solutions for coal-based power plants to operate recirculating cooling water systems at high cycles using impaired waters. The overall approach is to use combinations of novel membrane separations and scale inhibitor technologies that will work synergistically, with membrane separations reducing the scaling potential of the cooling water and scale inhibitors extending the safe operating range of the cooling water system. The project started on March 31, 2006 and ended in August 30, 2010. The project was a multiyear, multi-phase project with laboratory research and development as well as a small pilot-scale field demonstration. In Phase 1 (Technical Targets and Proof of Concept), the objectives were to establish quantitative technical targets and develop calcite and silica scale inhibitor chemistries for high stress conditions. Additional Phase I work included bench-scale testing to determine the feasibility of two membrane separation technologies (electrodialysis ED and electrode-ionization EDI) for scale minimization. In Phase 2 (Technology Development and Integration), the objectives were to develop additional novel scale inhibitor chemistries, develop selected separation processes, and optimize the integration of the technology components at the laboratory scale. Phase 3 (Technology Validation) validated the integrated system's performance with a pilot-scale demonstration. During Phase 1, Initial evaluations of impaired water characteristics focused on produced waters and reclaimed municipal wastewater effluents. Literature and new data were collected and evaluated. Characteristics of produced waters vary significantly from one site to another, whereas reclaimed municipal wastewater effluents have relatively more uniform characteristics. Assessment to date confirmed that calcite and silica

  7. Simplified model for determining local heat flux boundary conditions for slagging wall

    Energy Technology Data Exchange (ETDEWEB)

    Bingzhi Li; Anders Brink; Mikko Hupa [Aabo Akademi University, Turku (Finland). Process Chemistry Centre

    2009-07-15

    In this work, two models for calculating heat transfer through a cooled vertical wall covered with a running slag layer are investigated. The first one relies on a discretization of the velocity equation, and the second one relies on an analytical solution. The aim is to find a model that can be used for calculating local heat flux boundary conditions in computational fluid dynamics (CFD) analysis of such processes. Two different cases where molten deposits exist are investigated: the black liquor recovery boiler and the coal gasifier. The results show that a model relying on discretization of the velocity equation is more flexible in handling different temperature-viscosity relations. Nevertheless, a model relying on an analytical solution is the one fast enough for a potential use as a CFD submodel. Furthermore, the influence of simplifications to the heat balance in the model is investigated. It is found that simplification of the heat balance can be applied when the radiation heat flux is dominant in the balance. 9 refs., 7 figs., 10 tabs.

  8. Slagging and fouling evaluation of PC-fired boilers using AshPro{sup SM}

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhanhua; Iman, Felicia; Lu, Pisi [SmartBurn, LLC, Madison, WI (United States)

    2013-07-01

    SmartBurn {sup registered} applied AshPro{sup SM} model to two 512 MW Tangential-fired (T-fired) boilers firing US western sub- bituminous coals to evaluate the boiler slagging behaviors with different operating conditions and OFA. The boiler convective pass fouling behaviors with three different coals were also evaluated. The slagging evaluation results indicate that the OFA configuration and air flow distribution have dramatically impacts on the ash impaction rates and slagging patterns on the furnace walls. Deposit growth and strength vary at the different regions of the furnace walls. The fouling evaluation reveals that the tube bank configuration, the amount of incoming ash, the profiles of flue gas temperature, velocity, and species all have significant impacts on fouling deposit formation, growth, and strength development. In addition, the varying ash particle sizes and chemical compositions from different coals also play important roles on the fouling deposit strength development and removal. The investigation demonstrated that AshPro{sup SM} model can be used to evaluate localized slagging and fouling problems that are related to specific boiler configuration and operating conditions. It can be used to identify the major causes of ash deposition and can guide changes in boiler operation.

  9. Wetting Behavior of Calcium Ferrite Slags on Cristobalite Substrates

    Science.gov (United States)

    Yang, Mingrui; Lv, Xuewei; Wei, Ruirui; Xu, Jian; Bai, Chenguang

    2018-03-01

    Calcium ferrite (CF) is a significant intermediate adhesive phase in high-basicity sinters. The wettability between calcium ferrite (CF) and gangue plays an important role in the assimilation process. The wettability of CF-based slags, in which a constant amount (2 mass pct.) of Al2O3, MgO, SiO2, and TiO2 was added, on solid SiO2 (cristobalite) substrates at 1523 K (1250 °C) was investigated. The interfacial microstructure and spreading mechanisms were discussed for each sample. All the tested slag samples exhibited good wettability on the SiO2 substrate. The initial apparent contact angles were in the range of 20 to 50 deg, while the final apparent contact angles were 5 deg. The wetting process could be divided into three stages on the basis of the change in diameter, namely the "linear spreading" stage, "spreading rate reduction" stage, and "wetting equilibrium" stage. It was found that the CF-SiO2 wetting system exhibits dissolutive wetting and the dissolution of SiO2 into slag influences its spreading process. The spreading rate increases with a decrease in the ratio of viscosity to interfacial tension, which is a result of the addition of Al2O3, MgO, SiO2, and TiO2. After cooling, a deep corrosion pit was formed in the substrate and a diffusion layer was generated in front of the residual slag zone; further, some SiO2 and Fe2O3 solid solutions precipitated in the slag.

  10. Production of highly porous glass-ceramics from metallurgical slag, fly ash and waste glass

    OpenAIRE

    Mangutova Bianka V.; Fidancevska Emilija M.; Milosevski Milosav I.; Bossert Joerg H.

    2004-01-01

    Glass-ceramics composites were produced based on fly-ash obtained from coal power stations, metallurgical slag from ferronickel industry and waste glass from TV monitors, windows and flasks. Using 50% waste flask glass in combination with fly ash and 20% waste glass from TV screens in combination with slag, E-modulus and bending strength values of the designed systems are increased (system based on fly ash: E-modulus from 6 to 29 GPa, and bending strength from 9 to 75 MPa). The polyurethane f...

  11. Analysis and selection of a system for hydraulic transport of slags in the Mironovskii power plant

    Energy Technology Data Exchange (ETDEWEB)

    Mirgorodskii, V.G.; Mova, M.E.; Korenev, V.E.; Grechikhin, Yu.A. (Donetskii Politekhnicheskii Institut (USSR))

    1991-01-01

    Discusses systems for hydraulic transport of ashes and slags from combustion of black coal (with an ash content of 40.5%) in the Mironovskii power plant. Three systems are comparatively evaluated: hydraulic transport under influence of gravity, hydraulic transport with a system of dredging pumps, or an airlift pump system. Design of each system, its operation and types of pumps or airlift systems are discussed. The evaluation concentrates on the hydraulic transport system with 1 to 3 airlift pumps each with a capacity ranging from 110 to 890 m{sup 3}/h. Optimum design of the airlift hydraulic system for slag and ash transport is described.

  12. Utilization options for fly ash, bottom ash, and slag in Eastern Europe

    Energy Technology Data Exchange (ETDEWEB)

    Manz, O.E.

    1995-12-01

    Since 1967, at least six ash utilization symposiums have been held in the United States, with papers presented by several European authors on the utilization of coal by-products in Eastern Europe. There is currently over 80,000 megawatts of installed coal-fired capacity available in that region. Unfortunately, of the 117,778,000 tonnes of fly ash, bottom ash, and slag produced in Eastern Europe in 1989, only 13% was utilized. This paper outlines the research and levels and kinds of coal by-product utilization taking place in Eastern Europe since the late 1960s.

  13. Effects of Temperature, Oxygen Partial Pressure, and Materials Selection on Slag Infiltration into Porous Refractories for Entrained-Flow Gasifiers

    Science.gov (United States)

    Kaneko, Tetsuya Kenneth

    partial pressure of the operating atmosphere regulates the penetration of slag into refractory. The viscosity of the slag, which dictates its penetration rate, is influenced by the oxidation state of the Fe cation. Slag penetrations are shallower in oxidizing conditions than they are in reducing conditions because the iron-oxide from the slag solutions into the corundum-structured refractory and the slag is depleted of iron-oxide, increasing the viscosity of slags. Equally, the chemistries of both the refractory and slag materials dictate the course of penetration. Cr2O3-Al2O3 refractory limits mixed feedstock slag penetration through formation of a chromium spinel layer that functions as a physical obstacle against fluid flow. Al2O 3-SiO2 refractory limits eastern coal feedstock slag penetration as a result of refractory dissolution of SiO2, which increases the viscosity of slags. A physical model, which considers unidirectional fluid flow of slag through each pore of the porous microstructure of the refractory, sufficiently approximates the penetration depth of the slag into the refractory. Agreement between experiments and the physical model demonstrates that the slag is driven into the refractory by capillary pressure. Since the viscosity of the slag continuously changes as the slag travels through the inherent temperature gradient of the refractory lining, the model incorporates dynamic viscosities that are dependent on both temperature and composition to project depths that are unique to the experimental parameters. The significantly different length scales of the radial and penetration directions of the pores allows for the application of a lubrication approximation onto the momentum equation. This process produces an analytical solution that effectively envelopes the variable viscosity into a single term.

  14. Slags in steel making; Kuonat teraeksen valmistuksessa

    Energy Technology Data Exchange (ETDEWEB)

    Haerkki, J; Paeaetalo, M; Karhu, P; Jauhiainen, A; Alamaeki, P; Koski-Laine, S; Ollila, J [Oulu Univ. (Finland). Dept. of Process Engineering

    1997-12-31

    At the first step of the project all stages of the steelmaking processes were viewed from the blast furnace to the continuous casting. Slag knowledge of each processes were collected into a guide, which is meant to help both production and research. At the same time the essential problems caused by slags in steelmaking were focused. At the second step the focus of this slag-project were transferred into the desulphurization, converter, ladle and tundish slags. Wide slag knowledge has been divided into smaller parts and applied versatile into the steelmaking process taking into account the metallurgical, economical and qualitative aspects. (orig.) SULA 2 Research Programme; 13 refs.

  15. Slags in steel making; Kuonat teraeksen valmistuksessa

    Energy Technology Data Exchange (ETDEWEB)

    Haerkki, J.; Paeaetalo, M.; Karhu, P.; Jauhiainen, A.; Alamaeki, P.; Koski-Laine, S.; Ollila, J. [Oulu Univ. (Finland). Dept. of Process Engineering

    1996-12-31

    At the first step of the project all stages of the steelmaking processes were viewed from the blast furnace to the continuous casting. Slag knowledge of each processes were collected into a guide, which is meant to help both production and research. At the same time the essential problems caused by slags in steelmaking were focused. At the second step the focus of this slag-project were transferred into the desulphurization, converter, ladle and tundish slags. Wide slag knowledge has been divided into smaller parts and applied versatile into the steelmaking process taking into account the metallurgical, economical and qualitative aspects. (orig.) SULA 2 Research Programme; 13 refs.

  16. Study on cementitious properties of steel slag

    Directory of Open Access Journals (Sweden)

    Zhu G.

    2013-01-01

    Full Text Available The converter steel slag chemical and mineral components in China’s main steel plants have been analysed in the present paper. The electronic microscope, energy spectrum analysis, X-ray diffraction analysis confirmed the main mineral compositions in the converter slag. Converter slag of different components were grounded to obtain a powder with specific surface area over 400m2/kg, making them to take place some part of the cement in the concrete as the admixture and carry out the standard tests. The results indicate that the converter slag can be used as cementitious materials for construction. Furthermore, physical mechanic and durability tests on the concrete that certain amount of cement be substituted by converter steel slag powder from different steel plants are carried out, the results show that the concrete with partial substitution of steel slag powder has the advantages of higher later period strength, better frost resistance, good wear resistance and lower hydration heat, etc. This study can be used as the technical basis for “Steel Slag Powder Used For Cement And Concrete”, “Steel Slag Portland Cement”, “Low Heat Portland Steel Slag Cement”, “Steel Slag Road Cement” in China, as well as a driving force to the works of steel slag utilization with high-value addition, circular economy, energy conservation and discharge reduction in the iron and steel industry.

  17. Evaluation of technical feasibility of closed-cycle non-equilibrium MHD power generation with direct coal firing. Final report, Task 1

    Energy Technology Data Exchange (ETDEWEB)

    1981-11-01

    Program accomplishments in a continuing effort to demonstrate the feasibility of direct coal fired, closed cycle, magnetohydrodynamic power generation are detailed. These accomplishments relate to all system aspects of a CCMHD power generation system including coal combustion, heat transfer to the MHD working fluid, MHD power generation, heat and cesium seed recovery and overall systems analysis. Direct coal firing of the combined cycle has been under laboratory development in the form of a high slag rejection, regeneratively air cooled cyclone coal combustor concept, originated within this program. A hot bottom ceramic regenerative heat exchanger system was assembled and test fired with coal for the purposes of evaluating the catalytic effect of alumina on NO/sub x/ emission reduction and operability of the refractory dome support system. Design, procurement, fabrication and partial installation of a heat and seed recovery flow apparatus was accomplished and was based on a stream tube model of the full scale system using full scale temperatures, tube sizes, rates of temperature change and tube geometry. Systems analysis capability was substantially upgraded by the incorporation of a revised systems code, with emphasis on ease of operator interaction as well as separability of component subroutines. The updated code was used in the development of a new plant configuration, the Feedwater Cooled (FCB) Brayton Cycle, which is superior to the CCMHD/Steam cycle both in performance and cost. (WHK)

  18. Coal background paper. Coal demand

    International Nuclear Information System (INIS)

    1997-01-01

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

  19. Experiment research of slag renovation in the corner-fired boiler

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Zhijun; Wu, Wenfei [Inner Mongolia Univ. of Science and Technology, Baotou (China). School of Energy and Environment

    2013-07-01

    Aiming at serious slag on the water wall around the burner of corner-fired boiler with low-ash-fusion-point coal, cold experimental model has been established. In this experiment, particle image velocimetry (PIV) has been employed to accurately measure aerodynamic field of burner region, and the experimental research of furnace slag renovation has been conducted through changing the burner jet arrangement. The experiment results show that it has significantly effect on aerodynamic field in the furnace by changing burner jet deflection angle. A reasonable actual tangential circle diameter can be formed through adjusting the burner jet deflection angle, to prevent primary air attacking the wall, and further more, to effectively prevent serious slag on the water wall around the burner.

  20. Integrated coal preparation

    International Nuclear Information System (INIS)

    Buchanan, D.J.; Jones, T.F.

    1992-01-01

    Perceptions of quality have changed over the years. The attributes of a certain coal (its rank, slagging propensity, ash content etc) are traditionally referred to as its quality. However, the subject of this paper is quality in a much wider sense: quality as fitness for purpose: and all that such a wide definition entails. British Standard BS 5750 (ISO 9000) Quality Systems defines a systems approach to quality, and includes both the supplier of raw materials and the final customer within this boundary. Coal preparation starts at the production face. The greater the proportion of dirt in run-of-mine product the greater the challenge in satisfying the customer's needs. Significant advances have been made in minimizing mined dirt. For example, the sue of vertical steering on longwall faces improves productivity and quality. Unfortunately modern mining methods produce large quantities of fines, despite efforts to reduce them at the point of production and during transportation to the surface. Coal preparation also produces further fines. It has been estimated that fine coal costs 2.5 times as much to clean as large coal, and the costs of handing wet fine coal product will inflate this estimate. Handling considerations rightly concern our customers and are part of the wider meaning of quality. In this paper the authors address some novel solutions to the challenge posed by fines

  1. Coal combustion aerothermochemistry research. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Witte, A.B.; Gat, N.; Denison, M.R.; Cohen, L.M.

    1980-12-15

    On the basis of extensive aerothermochemistry analyses, laboratory investigations, and combustor tests, significant headway has been made toward improving the understanding of combustion phenomena and scaling of high swirl pulverized coal combustors. A special attempt has been made to address the gap between scientific data available on combustion and hardware design and scaling needs. Both experimental and theoretical investigations were conducted to improve the predictive capability of combustor scaling laws. The scaling laws derived apply to volume and wall burning of pulverized coal in a slagging high-swirl combustor. They incorporate the findings of this investigation as follows: laser pyrolysis of coal at 10/sup 6/ K/sec and 2500K; effect of coal particle shape on aerodynamic drag and combustion; effect of swirl on heat transfer; coal burnout and slag capture for 20 MW/sub T/ combustor tests for fine and coarse coals; burning particle trajectories and slag capture; particle size and aerodynamic size; volatilization extent and burnout fraction; and preheat level. As a result of this work, the following has been gained: an increased understanding of basic burning mechanisms in high-swirl combustors and an improved model for predicting combustor performance which is intended to impact hardware design and scaling in the near term.

  2. Research on the use of Ferro-Chrome slag in civil engineering applications

    Directory of Open Access Journals (Sweden)

    Al-Jabri Khalifa S.

    2018-01-01

    Full Text Available Over recent decades there has been rapid increase in the industrial waste materials and by-products yields due to the progressive growth rate of population, development of industry and technology and the growth of consumerism. With the growing environmental pressures to reduce waste and pollution, Intensive research studies have been conducted to explore all suitable reuse methods. Wastes such as construction waste, blast furnace, steel slag, coal fly ash and bottom ash have been approved in many places as alternative materials in bridges, roads, pavements, foundations and building construction. The use of industrial solid waste as a partial replacement of raw materials in construction activities not only saves landfill space but also reduces the demand for extraction of natural raw materials. Ferrochrome slag is a by-product from the production of chrome. There are environmental and economic advantages in seeing slags as a potentially useful resource rather than as waste products. Slag management at ferrochrome producing companies has been influenced by the limited space available and financial cost implications of the slag dumps. Internationally, e.g. South Africa, India, Norway, Turkey, East Europe, China, Sweden and USA, ferrochrome slag is used commercially in the road and construction Industries. This material is being used for road construction, as aggregates in concrete industry, brick manufacturing, and in pavement construction as engineering fill and has recently been tried in cement. This paper presents an overview of the recent advances of the use of ferrochrome slag in various civil engineering applications such as road construction, and cement and concrete industries.

  3. Room temperature zeolitization of boiler slag from a Bulgarian thermal power plant

    Directory of Open Access Journals (Sweden)

    Pascova Radost D.

    2017-01-01

    Full Text Available A simple and cost-effective method was applied for the synthesis of zeolite composites utilising wet bottom boiler slag from the Bulgarian coal-fired thermal power plant “Sviloza”, near the town of Svishtov. The method consisted of a prolonged alkali treatment at room temperature of this waste. Experimental techniques, such as scanning electron microscopy, energy-dispersive X-ray and X-ray diffraction analyses, are employed to characterize the initial slag and the final products with respect to their morphology, and elemental and mineral compositions. The composites synthesized in this way contained two Na-type zeolite phases: zeolite X (type FAU and zeolite Linde F (type EDI. The zeolited products and the starting slag were tested as adsorbents for a textile dye (Malachite Green from aqueous solutions. In comparison with the initial slag, the zeolite composite possessed substantially better adsorption properties: it almost completely adsorbs the dye in much shorter times. The results of this investigations revealed a new, easy and low cost route for recycling boiler slag into a material with good adsorption characteristics, which could find different applications, e.g., for purifying polluted waters, including those from the textile industry.

  4. Availability of arsenic, copper, lead, thallium, and zinc to various vegetables grown in slag-contaminated soils.

    Science.gov (United States)

    Bunzl, K; Trautmannsheimer, M; Schramel, P; Reifenhäuser, W

    2001-01-01

    To anticipate a possible hazard resulting from the plant uptake of metals from slag-contaminated soils, it is useful to study whether vegetables exist that are able to mobilize a given metal in the slag to a larger proportion than in an uncontaminated control soil. For this purpose, we studied the soil to plant transfer of arsenic, copper, lead, thallium, and zinc by the vegetables bean (Phaseolus vulgaris L. 'dwarf bean Modus'), kohlrabi (Brassica oleracea var. gongylodes L.), mangold (Beta vulgaris var. macrorhiza ), lettuce (Lactuca sativa L. 'American gathering brown'), carrot (Daucus carota L. 'Rotin', 'Sperlings's'), and celery [Apium graveiolus var. dulce (Mill.) Pers.] from a control soil (Ap horizon of a Entisol) and from a contaminated soil (1:1 soil-slag mixtures). Two types of slags were used: an iron-rich residue from pyrite (FeS2) roasting and a residue from coal firing. The metal concentrations in the slags, soils, and plants were used to calculate for each metal and soil-slag mixture the plant-soil fractional concentration ratio (CRfractional,slag), that is, the concentration ratio of the metal that results only from the slag in the soil. With the exception of TI, the resulting values obtained for this quantity for As, Cu, Pb, and Zn and for all vegetables were significantly smaller than the corresponding plant-soil concentration ratios (CRcontrol soil) for the uncontaminated soil. The results demonstrate quantitatively that the ability of a plant to accumulate a given metal as observed for a control soil might not exist for a soil-slag mixture, and vice versa.

  5. Mixture of industrial waste oxidized titanium and reduced slag from electric furnace used as hydraulic material. Denkiro kangen slug to sanka titan kogyo haikibutsu no kongobutsu no suinan zairyo to shiteno riyo

    Energy Technology Data Exchange (ETDEWEB)

    Honda, A [Osaka City University, Osaka (Japan). Faculty of Engineering; Kuwayama, T [Daido Institute of Technology, Nagoya (Japan); Yamada, M; Ikezaki, H [Osaka City University, Osaka (Japan). Faculty of Engineering

    1990-10-29

    Slag released from an electric furnace consists mainly of waste steel. There are two types of slag, namely, oxidized slag and reduced slag. Reduced slag, which is generally in the form of powder, is difficult to recycle as compared with oxidized slag. However, with a hydraulicity, some reduced slag is expected to be useful as hydraulic material. Test results obtained here show that the hydraulic properties of reduced slag powder can be improved by mixing it with gypsum and that the resultant mixture can serve to improve the prooperties of soft clay. Another study is made to determine the potential, as hydraulic material, of mixtures of reduced slag powder and waste gypsum material with a high gypsum content released from an oxidized titanium production process. The hydraulicity is found to develop as a result of the formation of a hydrate of calcium aluminate which is contained in the slag. Addition of water to the hydrate and gypsum cause the formation of ettringite, leading to an increased uniaxial compressive strength. These findings indicate that the above-mentioned mixture can be useful to improve the hydraulic properties of coal ash to be disposed of at landfill sites. 5 refs., 5 figs., 1 tab.

  6. Overview of hydraulic ash and slag transport in the Power Plantt 'Oslomej': Macedonia

    Directory of Open Access Journals (Sweden)

    Cvetanoski Radomir K.

    2017-01-01

    Full Text Available AD ELEM Skopje Subsidiary REK 'Oslomej' s. Oslomej is a part of the energy system with an installed power of 125 MW and the net average annual production of 500 GWh of electricity. The basic fuel is coal with an average of 7600 KJ/kg. Coal from the mine is provided Oslomej - west and old mine (Oslomej-east wherein 2009. excavated 1.156.709 t. The main aim of the project is solving environmental problems in Power Plant Oslomej and its surrounding area that creates the existing system of transport and disposal of ash and slag (transport of moist ash by conveyor belt at an open landfill, so the main task of this Project is introducing new technologies of transport and disposal of ash and slag in the form of hydro mixtures.

  7. Steel desulphurization with synthetic slag

    Directory of Open Access Journals (Sweden)

    Heput, T.

    2007-02-01

    Full Text Available Generally speaking, sulphur is considered a harmful element for steel quality, reason why all the technological steps are being taken in order to eliminate it from the metal bath. This paper deals with the influence of the chemical composition, on the slag quantity and of the bath stirring condition upon the desulphurization process in the casting ladle by treatment with synthetic slag. The experiments were made at an open-hearth plant with the steel tapping in two ladles (the desulphurization was made with synthetic slag at one ladle while the other one was considered standard and at the electric steel plant and for the synthetic slag formation a mix was used, made, according to several receipts, of: lime (50-75%, fluorine (0-17%, bauxite (0-32% and aluminous slag (8-22%. The data were processed in the calculation programs EXCEL and MATLAB, which resulted in a series of correlations between the desulphurization degree and the chemical composition of the slag, respectively the slag quantity both for the charges bubbled with Argon and the unbubbled ones.

    En general, el azufre es considerado un elemento nocivo para la calidad del acero y, por eso, en la práctica, se toman todas las medidas de orden tecnológico para su eliminación del baño metálico. En este trabajo se analiza la influencia de la composición química, de la cantidad de escoria y del estado de agitación del baño sobre el proceso de desulfuración en la cuchara para fundir por tratamiento con escoria sintética. Los experimentos se han realizado en una acería evacuando el acero en dos ollas (en una cuchara se efectuó la desulfuración con escoria sintética y a la otra se consideró como patrón y en un acería eléctrica y para la formación de la escoria sintética se utilizó una mezcla producida según muchas recetas, formada por: cal (50-75%, fluorina (0-17%, bauxita (0-32% y escoria aluminosa (8-22%. Los datos han sido procesados en los programas de c

  8. NEW TECHNOLOGY OF ASH AND SLAG CONCRETES

    Directory of Open Access Journals (Sweden)

    PAVLENKO T. M.

    2017-03-01

    Full Text Available Summary. Purpose. Development of scientific-technical bases of manufacture and application of concrete on the basis of ash and slag mixes of thermal power plants. Methods. It is proposed a new technology of preparation of ash and slag concrete mixes. First the ash and slag mix is dispersed through the sieve with meshes 5 mm in a fine-grained fraction and slag. Then, in accordance with the composition of the concrete, obtained fine-grained fraction, slag, cement and tempering water are separately dosed into the mixer. Results. It is proven the high efficiency of the proposed technology of manufacture of ash and slag concretes. It is established that this technological solution allows to increase the strength of concrete by 20...30%, and in the preparation of full-strength concrete to reduce the cement consumption by 15...20%. Scientific novelty. It is developed the new technology of ash and slag mixes application. The concrete mix on the basis of ash and slag mix has an optimal particle size distribution, which ensures the best compaction and, accordingly, the greatest strength of ash and slag concrete with the given cement consumption. Practical significance. The research results promote the mass application of ash and slag mixes of thermal power plants in construction, obtaining of products from the proposed concretes of low cost with high physical-mechanical properties. Conclusion. It is proven the high efficiency of the proposed technology of production of ash and slag concretes. It is established that this technological solution allows increasing concrete strength, and obtaining full-strength concrete to reduce cement consumption. The extensive application of such concrete in construction makes it possible to solve the problem of aggregates for concrete, promotes recycling of TPP waste and consequently the protection of the environment.

  9. The use of blast furnace slag

    Directory of Open Access Journals (Sweden)

    V. Václavík

    2012-10-01

    Full Text Available The paper presents the results of experimental research that dealt with the substitution of finely ground blast furnace slag for Portland cement in the course of simple concrete manufacturing. Physical and mechanical properties of experimental concrete mixtures based on finely ground blast furnace slag were observed.

  10. Leaching of heavy metals from steelmaking slags

    International Nuclear Information System (INIS)

    Gomez, J. F. P.; Pino, C. G.

    2006-01-01

    Leaching tests with EAF and Ladle slags were performed, using a flow through tests and the standard batch test DIN 38414-S4. The previous method was used to simulate the leaching behaviour of steel slags under landfill. the chemical analysis of the leachates during this period shows, in general, for both types of slag, and increase of heavy metal releases with ageing. Standard test method DIN 38414-S4 was used to evaluate leachability of heavy metals by water in unprocessed slags. After more than one year of trials, slang samples submitted to these trials presented very low total leaching levels. The most extracted elements are calcium and magnesium. Nevertheless, in flow-though test, calcium and magnesium leached from solid slags are below 0.5% and all other metals below 0.1%. Leachates obtained with DIN 38414-S4 present, as expected, higher leaching values; however, these are inferior to 5% (Ca) and 1% (other elements). (Author) 12 refs

  11. Mechanism of Selenium Loss in Copper Slag

    Science.gov (United States)

    Desai, Bhavin; Tathavadkar, Vilas; Basu, Somnath

    2018-06-01

    During smelting of copper sulfide concentrate, selenium is distributed between silica-saturated iron-silicate slag and copper-iron sulfide matte. The recovery coefficients of selenium between slag and matte were determined as a function of the initial concentration of selenium at 1523 K (1250 °C) under an inert atmosphere in a vertical tubular furnace. The initial concentration of selenium was varied by the addition of metallic selenium as well as selenium dioxide to the mixture of slag and matte. Analysis of the results indicated high affinity of selenium for matte. The apparent loss of selenium with the slag was attributed to the presence of selenium-enriched matte particles entrapped in the slag, rather than dissolved SeO2. The mechanisms proposed by previous investigators were discussed and also compared with the results of the present investigation.

  12. Mechanism of Selenium Loss in Copper Slag

    Science.gov (United States)

    Desai, Bhavin; Tathavadkar, Vilas; Basu, Somnath

    2018-03-01

    During smelting of copper sulfide concentrate, selenium is distributed between silica-saturated iron-silicate slag and copper-iron sulfide matte. The recovery coefficients of selenium between slag and matte were determined as a function of the initial concentration of selenium at 1523 K (1250 °C) under an inert atmosphere in a vertical tubular furnace. The initial concentration of selenium was varied by the addition of metallic selenium as well as selenium dioxide to the mixture of slag and matte. Analysis of the results indicated high affinity of selenium for matte. The apparent loss of selenium with the slag was attributed to the presence of selenium-enriched matte particles entrapped in the slag, rather than dissolved SeO2. The mechanisms proposed by previous investigators were discussed and also compared with the results of the present investigation.

  13. Agronomic Use of Basic Slag

    Directory of Open Access Journals (Sweden)

    Fabio Oliveiri de Nobile

    2015-01-01

    Full Text Available Modern civilization, in recent years, has increased the requirement of products derived from iron and steel, stimulating the growth of the national siderurgical sector and, consequently, the generation of industrial residue called basic slag. In this context, the recycling of residues can contribute to solve problems of the industries that give priority to the excellence of the production with quality. On the other hand, there is a sector of primary production in Brazil, the agriculture, with a great cultivated area in acid ground and with low fertility, being these factors admittedly determinative for vegetal production, under tropical conditions. Thus, there is a scenery of two primary sectors of production, although distinct ones, that present interaction potential, for , on one hand, there is disponibility of a product with similar properties to the liming materials and traditional fertilizers and, on the other hand, a production sector that is highly dependent of these products. And the interaction between these two sectors helps in the preservation of the environment, bringing, thus, a certain sustainability in the production systems of the postmodern civilization that will be the challenge of this new century. Considering the current possibility of recycling these industrial residues in agriculture, three important factors have to be taken into account. The first would be the proper use of the abundant, available and promising industrial residue; the second, in a propitious agricultural environment, acid soil and low fertility; and third, in a responsive and important socio-economic culture, the sugar cane, considering its vast cultivated area. In national literature, few works have dealt with the use of the basic slag and have evaluated the reply of the cultures to its application. Thus, the present work had as its aim to gather information from literature concerning the characterization and production of basic slag in Brazil, as well

  14. Geochemistry of coals, coal ashes and combustion wastes from coal-fired power stations

    International Nuclear Information System (INIS)

    Vassilev, S.V.; Vassileva, C.G.

    1997-01-01

    Contents, concentration trends, and modes of occurrence of 67 elements in coals, coal ashes, and combustion wastes at eleven Bulgarian thermoelectric power stations (TPS) were studied. A number of trace elements in coal and coal ash have concentrations greater than their respective worldwide average contents (Clarke values). Trace elements are concentrated mainly in the heavy accessory minerals and organic matter in coal. In decreasing order of significance, the trace elements in coal may occur as: element-organic compounds; impurities in the mineral matter; major components in the mineral matter; major and impurity components in the inorganic amorphous matter; and elements in the fluid constituent. A number of trace elements in the waste products, similar to coal ashes, exceed known Clarke contents. Trace elements are mainly enriched in non-magnetic, heavy and fine-grained fractions of fly ash. They are commonly present as impurities in the glass phases, and are included in the crystalline components. Their accessory crystalline phases, element-organic compounds, liquid and gas forms, are of subordinate importance. Some elements from the chalcophile, lithophile and siderophile groups may release into the atmosphere during coal burning. For others, the combustion process appears to be a powerful factor causing their relative enrichment in the fly ash and rarely in the bottom ash and slag. 65 refs., 1 fig., 11 tabs

  15. Natural radionuclides in coal and waste material originating from coal fired power plant

    International Nuclear Information System (INIS)

    Marovic, Gordana; Franic, Zdenko; Sencar, Jasminka; Petrinec, Branko; Bituh, Tomislav; Kovac, Jadranka

    2008-01-01

    This paper presents long-term investigations of natural radioactivity in coal, used for power production in the coal-fired power plant (CFPP) situated on the Adriatic coast, and resulting slag and ash. Activity concentrations of 40 K, 232 Th, 226 Ra and 238 U in used coal and resulting waste material have been measured for 25 years. As expected, it was demonstrated that the content of radionuclides in deposited bottom and filter ash material are closely related with radionuclide activity concentrations and mineral matter fraction in used coals. The external hazard index has been calculated and discussed for the slag and ash depository. During the first decade of operation of the CFPP has been used domestic coal produced in nearby area characterized by higher background radiation compared with the rest of Croatia. Therefore, the coal itself had relatively high 226 Ra and 238 U activity concentrations while potassium and thorium content was very low, 40 K activity concentrations being 2-9% and those of 232 Th 1-3% of total activity. As, in addition, the sulphur concentrations in coal were very high use of domestic coal was gradually abandoned till it was completely substituted by imported coal originated from various sources and of low natural radioactivity. Upon this, activity concentrations of uranium series radionuclides in deposited waste materials decreased significantly. Consequently, waste material i.e., slag and ash, generated in the last several years of coal fired power plant operation could be readily used in cement industry and as additive to other building materials, without any special restrictions according to the Croatian regulations dealing with building materials and European directives. (author)

  16. Processing and utilization of metallurgical slag

    Directory of Open Access Journals (Sweden)

    Alena Pribulová

    2016-06-01

    Full Text Available Metallurgy and foundry industry create a huge amount of slags that are by-products in production of pig iron, steel and cast iron. Slag is produced in a very large amount in pyrometallurgical processes, and is a huge source of waste if not properly recycled and utilized. With rapid growth of industrialization, land available for land-filling of large quantity of metallurgical slag is being reduced all over the world and disposal cost is becoming increasingly higher. Metallurgical slag from different metallurgical processes treated and utilized in different ways based on different slag characteristics. The most economic and efficient option for reducing metallurgical waste is through recycling, which is a significant contribution to saving natural resources and reducing CO2 emissions. Characteristic of slags as well as its treatment and utilization are given in the paper. Slag from pig iron and steel production is used most frequently in building industry. From experiments using blast furnace slag and granulated blast furnace slag as gravel, and water glass as binder it can be concluded that that the best results – the best values of compression strength and tensile strength were reached by using of 18% of water glass as a solidification activating agent. According to cubic compression strength, mixture from 50% blast furnace gravel, 50% granulated blast furnace slag and 18% water glass falls into C35/45 class of concrete. Such concrete also fulfils strength requirements for road concrete, moreover, it even exceeds them considerably and, therefore, it can find an application in construction of road communications or in production of concrete slabs.

  17. Evaluation of ash deposits during experimental investigation of co-firing of Bosnian coal with wooden biomass

    Energy Technology Data Exchange (ETDEWEB)

    Smajevic, Izet; Kazagic, Anes [JP Elektroprivreda BiH d.d., Sarajevo (Bosnia and Herzegovina); Sarajevo Univ. (Bosnia and Herzegovina). Faculty of Mechanical Engineering

    2008-07-01

    The paper is addressed to the development and use different criteria for evaluation of ash deposits collected during experimental co-firing of Bosnian coals with wooden biomass. Spruce saw dust was used for the co-firing tests with the Kakanj brown coal and with a lignite blend consisted of the Dubrave lignite and the Sikulje lignite. The coal/biomass mixtures at 93:7 %w and at 80:20 %w were tested. Experimental lab-scale facility PF entrained flow reactor is used for the co-firing tests. The reactor allows examination of fouling/slagging behaviors and emissions at various and infinitely variable process temperature which can be set at will in the range from ambient to 1560 C. Ash deposits are collected on two non-cooled ceramic probes and one water-cooled metal surface. Six different criteria are developed and used to evaluate behavior of the ash deposits on the probes: ash deposit shape, state and structure, which are analyzed visually - photographically and optically by a microscope, rate of adhesion and ash deposit strength, analyzed by physic acting to the ash deposits, and finally deposition rate, determined as a mass of the deposit divided by the collecting area and the time of collecting. Furthermore, chemical composition analysis and AFT of the ash deposits were also done to provide additional information on the deposits. (orig.)

  18. Coal geopolitics

    International Nuclear Information System (INIS)

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

    1991-01-01

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

  19. Gravitational segregation of liquid slag in large ladle

    Directory of Open Access Journals (Sweden)

    J. Chen

    2012-04-01

    Full Text Available The process of gravitational segregation makes liquid steel slag components occur differentiation. And it shows that the upper part slag in the slag ladle contains higher CaO; and the lower part slag contains higher SiO2. The content of MgO (5,48 % in the upper part slag is higher than that of the lower part (2,50 %, and only Al2O3 content of the upper and the lower part slag is close to each other. The difference of chemical compositions in the slag ladle shows that there is gravitational segregation during slow solidification of liquid steel slag, which will has some impact of the steel slag processing on the large slag ladle.

  20. Uranium recovery from slags of metallic uranium

    International Nuclear Information System (INIS)

    Fornarolo, F.; Frajndlich, E.U.C.; Durazzo, M.

    2006-01-01

    The Center of the Nuclear Fuel of the Institute of Nuclear Energy Research - IPEN finished the program of attainment of fuel development for research reactors the base of Uranium Scilicet (U 3 Si 2 ) from Hexafluoride of Uranium (UF 6 ) with enrichment 20% in weight of 235 U. In the process of attainment of the league of U 3 Si 2 we have as Uranium intermediate product the metallic one whose attainment generates a slag contend Uranium. The present work shows the results gotten in the process of recovery of Uranium in slags of calcined slags of Uranium metallic. Uranium the metallic one is unstable, pyrophoricity and extremely reactive, whereas the U 3 O 8 is a steady oxide of low chemical reactivity, what it justifies the process of calcination of slags of Uranium metallic. The calcination of the Uranium slag of the metallic one in oxygen presence reduces Uranium metallic the U 3 O 8 . Experiments had been developed varying it of acid for Uranium control and excess, nitric molar concentration gram with regard to the stoichiometric leaching reaction of temperature of the leaching process. The 96,0% income proves the viability of the recovery process of slags of Uranium metallic, adopting it previous calcination of these slags in nitric way with low acid concentration and low temperature of leaching. (author)

  1. Recent advances in the use of synchrotron radiation for the analysis of coal combustion products

    Energy Technology Data Exchange (ETDEWEB)

    Manowitz, B. [Brookhaven National Lab., Upton, NY (United States)

    1995-11-01

    Two major coal combustion problems are the formation and build-up of slag deposits on heat transfer surfaces and the production and control of toxic species in coal combustion emissions. The use of synchrotron radiation for the analysis of coal combustion products can play a role in the better understanding of both these phenomena. An understanding of the chemical composition of such slags under boiler operating conditions and as a function of the mineral composition of various coals is one ultimate goal of this program. The principal constituents in the ash of many coals are the oxides of Si, Al, Fe, Ca, K, S, and Na. The analytical method required must be able to determine the functional forms of all these elements both in coal and in coal ash at elevated temperatures. One unique way of conducting these analyses is by x-ray spectroscopy.

  2. Radiation doses in buildings containing coal

    International Nuclear Information System (INIS)

    Somlai, J.; Kanyar, B.; Nenyei, A.; Nemeth, Z.; Nemeth, Cs.

    2001-01-01

    Using coal-slag with high concentration of 226 Ra as building material could result excess dose of people living in these dwellings. The gamma dose rate, the radon concentration and the radionuclide concentration of built-in slags were measured in kindergartens, schools and homes of three towns (Ajka, Tatabanya, Varpalota). The absorbed dose rates exceeded significantly the world average (80 nGy/h) and the annual dose reached 3-4 mSv in some cases. The dose coming from radon is significant in the case of slags, which did not originate from power plants but from smaller stoves and furnaces because in these cases the burning temperature is lower, so the radon emanation is higher. The dose in the latter cases could reach 10-20 mSv/year. (author)

  3. Rare and Rare-Earth Metals in Coal Processing Waste

    Science.gov (United States)

    Cherkasova, Tatiana; Cherkasova, Elizaveta; Tikhomirova, Anastasia; Bobrovni-kova, Alyona; Goryunova, Irina

    2017-11-01

    An urgent issue for power plants operating on solid fuels (coal) is the issue of utilization or use of accumulated production waste - ash and slag materials - in the related production. Ash-slag materials are classified as "waste", usually grade 5; tens of millions of tons of them being pro-duced annually in the Kemerovo region, which threatens the ecology of the region. At the same time, ash and slag is a very promising raw material. The use of this material as a base for the final product allows us to signifi-cantly expand the possibilities of using coal. The most widespread is the system of ash and slag involving in construction or as a replacement for sand in road construction, or as an additive to building mixtures. However, there are both industrially valuable and environmentally dangerous ele-ments in ash-slag materials. Ash-slag materials can be considered as inde-pendent ore deposits located on the surface and requiring the costs of their extraction.

  4. Rare and Rare-Earth Metals in Coal Processing Waste

    Directory of Open Access Journals (Sweden)

    Cherkasova Tatiana

    2017-01-01

    Full Text Available An urgent issue for power plants operating on solid fuels (coal is the issue of utilization or use of accumulated production waste - ash and slag materials - in the related production. Ash-slag materials are classified as “waste”, usually grade 5; tens of millions of tons of them being pro-duced annually in the Kemerovo region, which threatens the ecology of the region. At the same time, ash and slag is a very promising raw material. The use of this material as a base for the final product allows us to signifi-cantly expand the possibilities of using coal. The most widespread is the system of ash and slag involving in construction or as a replacement for sand in road construction, or as an additive to building mixtures. However, there are both industrially valuable and environmentally dangerous ele-ments in ash-slag materials. Ash-slag materials can be considered as inde-pendent ore deposits located on the surface and requiring the costs of their extraction.

  5. Low-rank coal research: Volume 2, Advanced research and technology development: Final report

    Energy Technology Data Exchange (ETDEWEB)

    Mann, M.D.; Swanson, M.L.; Benson, S.A.; Radonovich, L.; Steadman, E.N.; Sweeny, P.G.; McCollor, D.P.; Kleesattel, D.; Grow, D.; Falcone, S.K.

    1987-04-01

    Volume II contains articles on advanced combustion phenomena, combustion inorganic transformation; coal/char reactivity; liquefaction reactivity of low-rank coals, gasification ash and slag characterization, and fine particulate emissions. These articles have been entered individually into EDB and ERA. (LTN)

  6. Uranium recovery from AVLIS slag

    International Nuclear Information System (INIS)

    D'Agostino, A.E.; Mycroft, J.R.; Oliver, A.J.; Schneider, P.G.; Richardson, K.L.

    2000-01-01

    Uranium metal for the Atomic Vapor Laser Isotope Separation (AVLIS) project was to have been produced by the magnesiothermic reduction of uranium tetrafluoride. The other product from this reaction is a magnesium fluoride slag, which contains fine and entrained natural uranium as metal and oxide. Recovery of the uranium through conventional mill leaching would not give a magnesium residue free of uranium but to achieve more complete uranium recovery requires the destruction of the magnesium fluoride matrix and liberation of the entrapped uranium. Alternate methods of carrying out such treatments and the potential for recovery of other valuable byproducts were examined. Based on the process flowsheets, a number of economic assessments were performed, conclusions were drawn and the preferred processing alternatives were identified. (author)

  7. Improvement to Air2Air Technology to Reduce Fresh-Water Evaporative Cooling Loss at Coal-Based Thermoelectric Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Ken Mortensen

    2011-12-31

    This program was undertaken to enhance the manufacturability, constructability, and cost of the Air2Air{TM} Water Conservation and Plume Abatement Cooling Tower, giving a validated cost basis and capability. Air2Air{TM} water conservation technology recovers a portion of the traditional cooling tower evaporate. The Condensing Module provides an air-to-air heat exchanger above the wet fill media, extracting the heat from the hot saturated moist air leaving in the cooling tower and condensing water. The rate of evaporate water recovery is typically 10% - 25% annually, depending on the cooling tower location (climate). This program improved the efficiency and cost of the Air2Air{TM} Water Conservation Cooling Tower capability, and led to the first commercial sale of the product, as described.

  8. Advances in chemical and physical properties of electric arc furnace carbon steel slag by hot stage processing and mineral mixing

    International Nuclear Information System (INIS)

    Liapis, Ioannis; Papayianni, Ioanna

    2015-01-01

    Highlights: • Addition of 10% perlite decreases specific weight of the slag by approx. 7.5%. • Slag-crucible interaction and thin coating layer result in variations in XRF. • XRD shows high glass content and smaller crystalline sizes due to rapid cooling. • SEM shows higher homogeneity and lower crystallisation for SiO 2 /CaO-rich samples. • Physical properties (LA, PSV, AAV) of modified slag show limited deterioration. - Abstract: Slags are recognised as a highly efficient, cost effective tool in the metal processing industry, by minimising heat losses, reducing metal oxidation through contact with air, removing metal impurities and protecting refractories and graphite electrodes. When compared to natural aggregates for use in the construction industry, slags have higher specific weight that acts as an economic deterrent. A method of altering the specific weight of EAFC slag by hot stage processing and mineral mixing, during steel production is presented in this article. The method has minimal interference with the production process of steel, even by limited additions of appropriate minerals at high temperatures. Five minerals are examined, namely perlite, ladle furnace slag, bauxite, diatomite and olivine. Measurements of specific weight are accompanied by X-ray diffraction (XRD) and fluorescence (XRF) analysis and scanning electron microscopy spectral images. It is also shown how altering the chemical composition is expected to affect the furnace refractory lining. Additionally, the process has been repeated for the most suitable mix in gas furnace and physical properties (FI, SI, LA, PSV, AAV, volume stability) examined. Alteration of the specific weight can result in tailoring slag properties for specific applications in the construction sector

  9. Advances in chemical and physical properties of electric arc furnace carbon steel slag by hot stage processing and mineral mixing

    Energy Technology Data Exchange (ETDEWEB)

    Liapis, Ioannis, E-mail: iliapis@sidenor.vionet.gr [AEIFOROS SA, 12th km Thessaloniki-Veroia Rd, PO Box 59, 57008 Ionia, Thessaloniki (Greece); Papayianni, Ioanna [Laboratory of Building Materials, Department of Civil Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

    2015-02-11

    Highlights: • Addition of 10% perlite decreases specific weight of the slag by approx. 7.5%. • Slag-crucible interaction and thin coating layer result in variations in XRF. • XRD shows high glass content and smaller crystalline sizes due to rapid cooling. • SEM shows higher homogeneity and lower crystallisation for SiO{sub 2}/CaO-rich samples. • Physical properties (LA, PSV, AAV) of modified slag show limited deterioration. - Abstract: Slags are recognised as a highly efficient, cost effective tool in the metal processing industry, by minimising heat losses, reducing metal oxidation through contact with air, removing metal impurities and protecting refractories and graphite electrodes. When compared to natural aggregates for use in the construction industry, slags have higher specific weight that acts as an economic deterrent. A method of altering the specific weight of EAFC slag by hot stage processing and mineral mixing, during steel production is presented in this article. The method has minimal interference with the production process of steel, even by limited additions of appropriate minerals at high temperatures. Five minerals are examined, namely perlite, ladle furnace slag, bauxite, diatomite and olivine. Measurements of specific weight are accompanied by X-ray diffraction (XRD) and fluorescence (XRF) analysis and scanning electron microscopy spectral images. It is also shown how altering the chemical composition is expected to affect the furnace refractory lining. Additionally, the process has been repeated for the most suitable mix in gas furnace and physical properties (FI, SI, LA, PSV, AAV, volume stability) examined. Alteration of the specific weight can result in tailoring slag properties for specific applications in the construction sector.

  10. Leaching of aluminum and iron from boiler slag generated from a typical Chinese Steel Plant.

    Science.gov (United States)

    Li, Jinping; Gan, Jinhua; Li, Xianwang

    2009-07-30

    This paper presents a new way of recycling aluminum and iron in boiler slag derived from coal combustion plants, which integrates efficient extraction and reuse of the leached pellets together. The boiler slag was pelletized together with washed coal and lime prior to sintering and then was sintered at 800-1200 degrees C for different periods to produce sintered pellets for the leaching test. An elemental analysis of aqueous solutions leached by sulfuric acid was determined by EDTA-Na(2)-ZnCl(2) titration method. The components and microstructures of the samples, sintered pellets and leached residue were examined by means of XRF, XRD and SEM. XRD analysis indicates that predominate minerals such as kaolinite, quartz, calcium silicide, hematate and metakoalin exist in the boiler slag. An aluminum extraction efficiency of 86.50% was achieved. The maximum extraction efficiency of Fe was 94.60% in the same conditions of that for the maximum extraction efficiency of Al. The extraction efficiencies of Al and Fe increased with an increase in temperature, leaching time and acidity. High Al extraction efficiency was obtained for pellets with high CaO content. The final product of alumina would be used directly for the production of metallic aluminum.

  11. Reduction of acid rock drainage using steel slag in cover systems over sulfide rock waste piles.

    Science.gov (United States)

    de Almeida, Rodrigo Pereira; Leite, Adilson do Lago; Borghetti Soares, Anderson

    2015-04-01

    The extraction of gold, coal, nickel, uranium, copper and other earth-moving activities almost always leads to environmental damage. In metal and coal extraction, exposure of sulfide minerals to the atmosphere leads to generation of acid rock drainage (ARD) and in underground mining to acid mine drainage (AMD) due to contamination of infiltrating groundwater. This study proposes to develop a reactive cover system that inhibits infiltration of oxygen and also releases alkalinity to increase the pH of generated ARD and attenuate metal contaminants at the same time. The reactive cover system is constructed using steel slag, a waste product generated from steel industries. This study shows that this type of cover system has the potential to reduce some of the adverse effects of sulfide mine waste disposal on land. Geochemical and geotechnical characterization tests were carried out. Different proportions of sulfide mine waste and steel slag were studied in leachate extraction tests. The best proportion was 33% of steel slag in dry weight. Other tests were conducted as follows: soil consolidation, saturated permeability and soil water characteristic curve. The cover system was numerically modeled through unsaturated flux analysis using Vadose/w. The solution proposed is an oxygen transport barrier that allows rain water percolation to treat the ARD in the waste rock pile. The results showed that the waste pile slope is an important factor and the cover system must have 5 m thickness to achieve an acceptable effectiveness. © The Author(s) 2015.

  12. Technologically enhanced natural radioactivity around the coal fired power plant

    International Nuclear Information System (INIS)

    Kovac, J.; Marovic, G.

    1997-01-01

    In some situations the exposure to natural radiation sources is enhanced as a result to technological developments. Burning of coal is one source of enhanced radiation exposure to naturally occurring elements, particularly radium, thorium and uranium. Most of the radioactive substances are concentrated in the ash and slag, which are heavy and drop to the bottom of a furnace. Lighter fly ash is carried up the chimney and into the atmosphere. The bottom ash and slag are usually deposited in a waste pile, from where some activity may leach into aquifers or be dispersed by wind.The main pathways through which the populations living around coal fired power plants are exposed to enhanced levels of natural radionuclides are inhalation and ingestion of the activity discharged into the Exosphere. For this reason, extensive investigations have been under way for several years in the coal fired power plant in Croatia, which uses an anthracite coal with a higher than usual uranium content. (authors)

  13. Thermal and sintering characterization of IGCC slag

    Energy Technology Data Exchange (ETDEWEB)

    Acosta, A.; Iglesias, I.; Aineto, M.; Romero, M.; Rincon, J.M. [University of Castilla La Mancha, Ciudad Real (Spain)

    2002-07-01

    IGCC slag is a vitreous residual product from the new induction gasification combined cycle gasification thermal power plants. In order to characterize this waste as secondary raw material for the production of glasses and glass-ceramics as construction materials, slag from the Puertollano, Ciudad Real, Spain power plants was thermally investigated. After controlled heating this waste gives rise to hematite, anorthite, and cristobalite crystallized materials.

  14. The use of steel slag in concrete

    Science.gov (United States)

    Martauz, P.; Vaclavik, V.; Cvopa, B.

    2017-10-01

    This paper presents the results of a research dealing with the use of unstable steel slag as a 100% substitute for natural aggregate in the production of concrete. Portland cement CEM I 42.5N and alkali activated hybrid cement H-CEMENT were used as the binder. The test results confirm the possibility to use steel slag as the filler in the production of concrete.

  15. Acid slag injection into the blast furnace tuyere zone

    Energy Technology Data Exchange (ETDEWEB)

    Haerkki, J; Tervola, K [Oulu Univ. (Finland). Dept. of Process Engineering

    1997-12-31

    The possibility of acid slag injection and its effect on the slag formation and on the melting behaviour of the charge materials are studied in the present work. The work is partly based on the literature evaluating the slag formation, slag properties and the basic slag injection. The possibility of acid slag injection is first examined by studying changes in the composition of the primary slag if the share of the acid slag component (Kostamus pellet/RR) of the charge material is lowered. Phase diagrams and viscosity charts are used to evaluate the viscosity, and solidus/liquidus temperature in the slag phase. The share of the slag phase of the pellet is evaluated by calculating the amount of the acid slag injection. The injection rate of some injectants is also examined. The primary slag formed of the sinter and the coke ash is in liquid form and its viscosity is close to the viscosity of the blast furnace slag. It is possible that the liquid slag phase can be formed in the blast furnace without the presence of the acid pellet because the melting point and the viscosity of the slag is lowered by alkalies, sulfur and the dissolved ironoxide of the slag. If high SiO{sub 2} content materials alone are used for injection there is a risk that the slag phase of the tuyere zone becomes too viscous. Olivine and some iron containing components such as fayalite are possible injection material. More information is needed to evaluate the effect of acid slag injection on the operation of the blast furnace. (orig.) SULA 2 Research Programme; 2 refs.

  16. Acid slag injection into the blast furnace tuyere zone

    Energy Technology Data Exchange (ETDEWEB)

    Tervola, K.; Haerkki, J.

    1996-12-31

    The possibility of acid slag injection and its effect on the slag formation and on the melting behaviour of the charge materials are studied in the present work. The work is partly based on the literature evaluating the slag formation, slag properties and the basic slag injection. The possibility of acid slag injection is first examined by studying changes in the composition of the primary slag if the share of the acid slag component (Kostamus pellet/RR) of the charge material is lowered. Phase diagrams and viscosity charts are used to evaluate the viscosity, and solidus/liquids temperature in the slag phase. The share of the slag phase of the pellet is evaluated by calculating the amount of the acid slag injection. The injection rate of some injectants is also examined. The primary slag formed of the sinter and the coke ash is in liquid form and its viscosity is close to the viscosity of the blast furnace slag. It is possible that the liquid slag phase can be formed in the blast furnace without the presence of the acid pellet because the melting point and the viscosity of the slag is lowered by alkalies, sulfur and the dissolved ironoxide of the slag. If high SiO{sub 2} content materials alone are used for injection there is a risk that the slag phase of the tuyere zone becomes too viscous. Olivine and some iron containing components such as fayalite are possible injection material. More information is needed to evaluate the effect of acid slag injection on the operation of the blast furnace. (orig.) (14 refs.)

  17. Acid slag injection into the blast furnace tuyere zone

    Energy Technology Data Exchange (ETDEWEB)

    Haerkki, J.; Tervola, K. [Oulu Univ. (Finland). Dept. of Process Engineering

    1996-12-31

    The possibility of acid slag injection and its effect on the slag formation and on the melting behaviour of the charge materials are studied in the present work. The work is partly based on the literature evaluating the slag formation, slag properties and the basic slag injection. The possibility of acid slag injection is first examined by studying changes in the composition of the primary slag if the share of the acid slag component (Kostamus pellet/RR) of the charge material is lowered. Phase diagrams and viscosity charts are used to evaluate the viscosity, and solidus/liquidus temperature in the slag phase. The share of the slag phase of the pellet is evaluated by calculating the amount of the acid slag injection. The injection rate of some injectants is also examined. The primary slag formed of the sinter and the coke ash is in liquid form and its viscosity is close to the viscosity of the blast furnace slag. It is possible that the liquid slag phase can be formed in the blast furnace without the presence of the acid pellet because the melting point and the viscosity of the slag is lowered by alkalies, sulfur and the dissolved ironoxide of the slag. If high SiO{sub 2} content materials alone are used for injection there is a risk that the slag phase of the tuyere zone becomes too viscous. Olivine and some iron containing components such as fayalite are possible injection material. More information is needed to evaluate the effect of acid slag injection on the operation of the blast furnace. (orig.) SULA 2 Research Programme; 2 refs.

  18. A quantitative assessment of the BSE risk associated with fly ash and slag from the incineration of meat-and-bone meal in a gas-fired power plant in Denmark

    DEFF Research Database (Denmark)

    Paisley, Larry; Hostrup-Pedersen, J.

    2005-01-01

    and slag are incorporated into the cement or concrete. Our goal was to assess with a Monte Carlo simulation model the bovine spongiform, encephalopathy (BSE) risk to cattle and humans posed by the ash and slag. The results will be used by decision makers to evaluate the need for disposal of the fly ash......It has been recommended that meat-and-bone meal (MBM) be incinerated at 850 degrees C for at least 2 s and the ashes and slag disposed of in controlled landfills, to dispose of animal-derived proteins. Most commonly, the MBM is incinerated in cement works or coal-fired power plants and the ashes...

  19. Computational Fluid Dynamics (CFD) Investigation of Submerged Combustion Behavior in a Tuyere Blown Slag-fuming Furnace

    Science.gov (United States)

    Huda, Nazmul; Naser, Jamal; Brooks, G. A.; Reuter, M. A.; Matusewicz, R. W.

    2012-10-01

    A thin-slice computational fluid dynamics (CFD) model of a conventional tuyere blown slag-fuming furnace has been developed in Eulerian multiphase flow approach by employing a three-dimensional (3-D) hybrid unstructured orthographic grid system. The model considers a thin slice of the conventional tuyere blown slag-fuming furnace to investigate details of fluid flow, submerged coal combustion dynamics, coal use behavior, jet penetration behavior, bath interaction conditions, and generation of turbulence in the bath. The model was developed by coupling the CFD with the kinetics equations developed by Richards et al. for a zinc-fuming furnace. The model integrates submerged coal combustion at the tuyere tip and chemical reactions with the heat, mass, and momentum interfacial interaction between the phases present in the system. A commercial CFD package AVL Fire 2009.2 (AVL, Graz, Austria) coupled with several user-defined subroutines in FORTRAN programming language were used to develop the model. The model predicted the velocity, temperature field of the molten slag bath, generated turbulence and vortex, and coal use behavior from the slag bath. The tuyere jet penetration length ( l P) was compared with the equation provided by Hoefele and Brimacombe from isothermal experimental work ( {{l_{{P}} }/{d_{o }} = 10.7( {N^' }_{Fr} } )^{0.46} ( {ρ_{{g}} /ρl } )^{0.35} } ) and found 2.26 times higher, which can be attributed to coal combustion and gas expansion at a high temperature. The jet expansion angle measured for the slag system studied is 85 deg for the specific inlet conditions during the simulation time studied. The highest coal penetration distance was found to be l/L = 0.2, where l is the distance from the tuyere tip along the center line and L is the total length (2.44 m) of the modeled furnace. The model also predicted that 10 pct of the injected coal bypasses the tuyere gas stream uncombusted and carried to the free surface by the tuyere gas stream, which

  20. The hydration of slag, part 1: reaction models for alkali-activated slag

    NARCIS (Netherlands)

    Chen, Wei; Brouwers, H.J.H.

    2007-01-01

    Reaction models are proposed to quantify the hydration products and to determine the composition of C–S–H from alkali-activated slags (AAS). Products of the slag hydration are first summarized from observations in literature. The main hydration products include C–S–H, hydrotalcite, hydrogarnet, AFm

  1. Development and Testing of Industrial Scale Coal Fired Combustion System, Phase 3

    Energy Technology Data Exchange (ETDEWEB)

    Bert Zauderer

    1998-09-30

    Coal Tech Corp's mission is to develop, license & sell innovative, lowest cost, solid fuel fired power systems & total emission control processes using proprietary and patented technology for domestic and international markets. The present project 'DEVELOPMENT & TESTING OF INDUSTRIAL SCALE, COAL FIRED COMBUSTION SYSTEM, PHASE 3' on DOE Contract DE-AC22-91PC91162 was a key element in achieving this objective. The project consisted of five tasks that were divided into three phases. The first phase, 'Optimization of First Generation 20 MMBtu/hr Air-Cooled Slagging Coal Tech Combustor', consisted of three tasks, which are detailed in Appendix 'A' of this report. They were implemented in 1992 and 1993 at the first generation, 20 MMBtu/hour, combustor-boiler test site in Williamsport, PA. It consisted of substantial combustor modifications and coal-fired tests designed to improve the combustor's wall cooling, slag and ash management, automating of its operation, and correcting severe deficiencies in the coal feeding to the combustor. The need for these changes was indicated during the prior 900-hour test effort on this combustor that was conducted as part of the DOE Clean Coal Program. A combination of combustor changes, auxiliary equipment changes, sophisticated multi-dimensional combustion analysis, computer controlled automation, and series of single and double day shift tests totaling about 300 hours, either resolved these operational issues or indicated that further corrective changes were needed in the combustor design. The key result from both analyses and tests was that the combustor must be substantially lengthened to maximize combustion efficiency and sharply increase slag retention in the combustor. A measure of the success of these modifications was realized in the third phase of this project, consisting of task 5 entitled: 'Site Demonstration with the Second Generation 20 MMBtu/hr Air-Cooled Slagging Coal Tech

  2. Effect of Slag Composition on the Crystallization Kinetics of Synthetic CaO-SiO2-Al2O3-MgO Slags

    Science.gov (United States)

    Esfahani, Shaghayegh; Barati, Mansoor

    2018-04-01

    The crystallization kinetics of CaO-SiO2-Al2O3-MgO (CSAM) slags was studied with the aid of single hot thermocouple technique (SHTT). Kinetic parameters such as the Avrami exponent ( n), rate coefficient ( K), and effective activation energy of crystallization ( E A ) were obtained by kinetic analysis of data obtained from in situ observation of glassy to crystalline transformation and image analysis. Also, the dependence of nucleation and growth rates of crystalline phases were quantified as a function of time, temperature, and slag basicity. Together with the observations of crystallization front, they facilitated establishing the dominant mechanisms of crystallization. In an attempt to predict crystallization rate under non-isothermal conditions, a mathematical model was developed that employs the rate data of isothermal transformation. The model was validated by reproducing an experimental continuous cooling transformation diagram purely from isothermal data.

  3. EPR as a tool for studying slags and slag-like systems

    Energy Technology Data Exchange (ETDEWEB)

    Slezak, A.; Lech, J. [Institute of Physics, Technical University of Czestochowa, Czestochowa (Poland)

    1997-12-31

    Results of possible applications of the EPR method for studying of steelwork slags properties and sintering processes involving some slag components are presented. Comparative experimental studies have been carried out at X-band both industrial slags and synthetic slag-like systems obtained by sintering mixtures of pure reagents of Ca-Al{sub 2}O{sub 3}-Fe{sub 2}O{sub 3} phase diagram. Tests of evolution of EPR spectra during sintering process have also been done, including sintering row mixtures currently used in cement industry. EPR spectra of Mn{sup 2+} ions, which have been observed quite resolved in nearly all studied samples, have been established very useful for studying kinetics of sintering process in systems involving the slags and components of the CaO-Al{sub 2}O{sub 3}-SiO{sub 2} diagram. (author). 20 refs, 5 figs, 1 tab.

  4. Decalcification resistance of alkali-activated slag

    Energy Technology Data Exchange (ETDEWEB)

    Komljenovic, Miroslav M., E-mail: miroslav.komljenovic@imsi.rs [Institute for Multidisciplinary Research, University of Belgrade, Kneza Viseslava 1, 11030 Belgrade (Serbia); Bascarevic, Zvezdana, E-mail: zvezdana@imsi.bg.ac.rs [Institute for Multidisciplinary Research, University of Belgrade, Kneza Viseslava 1, 11030 Belgrade (Serbia); Marjanovic, Natasa, E-mail: natasa@imsi.bg.ac.rs [Institute for Multidisciplinary Research, University of Belgrade, Kneza Viseslava 1, 11030 Belgrade (Serbia); Nikolic, Violeta, E-mail: violeta@imsi.bg.ac.rs [Institute for Multidisciplinary Research, University of Belgrade, Kneza Viseslava 1, 11030 Belgrade (Serbia)

    2012-09-30

    Highlights: Black-Right-Pointing-Pointer The effects of decalcification on properties of alkali-activated slag were studied. Black-Right-Pointing-Pointer Decalcification was performed by concentrated NH{sub 4}NO{sub 3} solution (accelerated test). Black-Right-Pointing-Pointer Portland-slag cement (CEM II/A-S 42.5 N) was used as a benchmark material. Black-Right-Pointing-Pointer Decalcification led to strength decrease and noticeable structural changes. Black-Right-Pointing-Pointer Alkali-activated slag showed significantly higher resistance to decalcification. - Abstract: This paper analyses the effects of decalcification in concentrated 6 M NH{sub 4}NO{sub 3} solution on mechanical and microstructural properties of alkali-activated slag (AAS). Portland-slag cement (CEM II/A-S 42.5 N) was used as a benchmark material. Decalcification process led to a decrease in strength, both in AAS and in CEM II, and this effect was more pronounced in CEM II. The decrease in strength was explicitly related to the decrease in Ca/Si atomic ratio of C-S-H gel. A very low ratio of Ca/Si {approx}0.3 in AAS was the consequence of coexistence of C-S-H(I) gel and silica gel. During decalcification of AAS almost complete leaching of sodium and tetrahedral aluminum from C-S-H(I) gel also took place. AAS showed significantly higher resistance to decalcification in relation to the benchmark CEM II due to the absence of portlandite, high level of polymerization of silicate chains, low level of aluminum for silicon substitution in the structure of C-S-H(I), and the formation of protective layer of polymerized silica gel during decalcification process. In stabilization/solidification processes alkali-activated slag represents a more promising solution than Portland-slag cement due to significantly higher resistance to decalcification.

  5. How can we reduce carbon in ash in firing pulverized coal

    Energy Technology Data Exchange (ETDEWEB)

    O' Keefe, W. (and others)

    1992-12-01

    The article discusses solutions to the problem of reducing carbon in ash in firing pulverized coal. Suggested solutions to the problem include: reviewing air flow through the mills; examining the pulverizers for coal fineness variations; investigating air distribution in the burners; review dual-firing equations; examining the burners for slag build up; checking coal fineness is appropriate to the boiler; increasing air flow; and checking instrumentation. 2 figs., 1 photo.

  6. Influence of the slags treatment on the heavy metals binding

    Czech Academy of Sciences Publication Activity Database

    Blahová, L.; Navrátilová, Z.; Mucha, M.; Navrátilová, Eva; Neděla, Vilém

    2018-01-01

    Roč. 15, č. 4 (2018), s. 697-706 ISSN 1735-1472 Institutional support: RVO:68081731 Keywords : slag * binding * metal cations * slag modification Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.915, year: 2016

  7. Process-integrated slag treatment; Prozessintegrierte Schlackebehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Koralewska, R.; Faulstich, M. [Technische Univ., Garching (Germany). Lehrstuhl fuer Wasserguete- und Abfallwirtschaft

    1998-09-01

    The present study compares two methods of washing waste incineration slag, one with water only, and one which uses additives during wet deslagging. The presented aggregate offers ideal conditions for process-integrated slag treatment. The paper gives a schematic description of the integrated slag washing process. The washing liquid serves to wash out the readily soluble constituents and remove the fines, while the additives are for immobilising heavy metals in the slag material. The study is based on laboratory and semi-technical trials on the wet chemical treatment of grate slag with addition of carbon dioxide and phosphoric acid. [Deutsch] Die dargestellten Untersuchungen beziehen sich auf den Vergleich zwischen einer Waesche der Muellverbrennungsschlacke mit Wasser und unter Zugabe von Additiven im Nassentschlacker. In diesem Aggregat bieten sich optimale Voraussetzungen fuer eine prozessintegrierte Schlackebehandlung. Die Durchfuehrung der integrierten Schlackewaesche wird schematisch gezeigt. Durch die Waschfluessigkeit sollen die leichtloeslichen Bestandteile ausgewaschen und die Feinanteile ausgetragen sowie durch die Additive zusaetzlich die Schwermetalle im Schlackematerial immobilisiert werden. Dazu erfolgten Labor- und halbtechnische Versuche zur nasschemischen Behandlung der Rostschlacken unter Zugabe von Kohlendioxid und Phosphorsaeure. (orig./SR)

  8. Inclined fluidized bed system for drying fine coal

    Science.gov (United States)

    Cha, Chang Y.; Merriam, Norman W.; Boysen, John E.

    1992-02-11

    Coal is processed in an inclined fluidized bed dryer operated in a plug-flow manner with zonal temperature and composition control, and an inert fluidizing gas, such as carbon dioxide or combustion gas. Recycled carbon dioxide, which is used for drying, pyrolysis, quenching, and cooling, is produced by partial decarboxylation of the coal. The coal is heated sufficiently to mobilize coal tar by further pyrolysis, which seals micropores upon quenching. Further cooling with carbon dioxide enhances stabilization.

  9. Preparing hydraulic cement from oil-shale slag

    Energy Technology Data Exchange (ETDEWEB)

    1921-11-19

    A process for the preparation of hydraulic cementing material from oil shale or oil-shale slag according to Patent 411,584 is characterized by the fact that the oil-shale slag is added to burnt marl, blast-furnace slag, and the like, whereupon the mixture is milled to dust in the known way.

  10. Environmental characteristics and utilization potential of metallurgical slag: Chapter 19

    Science.gov (United States)

    Piatak, Nadine; De Vivo, Benedetto; Belkin, Harvey E.; Lima, Annamaria

    2018-01-01

    Slag, an abundant byproduct from the pyrometallurgical processing of ores, can be an environmental liability or a valuable resource. The most common environmental impact of slag is from the leaching of potentially toxic elements, acidity, or alkalinity that may impact nearby soils and surface water and groundwater. Factors that influence its environmental behavior include physical characteristics, such as grain size and porosity, chemical composition with some slag being enriched in certain elements, the mineralogy and partitioning of elements in more or less reactive phases, water-slag interactions, and site conditions. Many of these same factors also influence its resource potential. For example, crystalline ferrous slag is most commonly used as construction aggregate, whereas glassy (i.e., granulated) slag is used in cement. Also, the calcium minerals found in ferrous slag result in useful applications in water treatment. In contrast, the high trace-element content of some base-metal slags makes the slags economically attractive for extraction of residual elements. An evaluation tool is used to help categorize a particular slag as an environmental hazard or valuable byproduct. Results for one type of slag, legacy steelmaking slag from the Chicago area in the USA, suggest the material has potential to be used for treating phosphate-rich or acidic waters; however, the pH and trace-element content of resulting solutions may warrant further examination.

  11. Experimental determination and numerical simulation of viscositites in slag-systems under gasification conditions; Experimentelle Bestimmung und numerische Simulation von Viskositaeten in Schlackesystemen unter Vergasungsbedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Nentwig, Thomas

    2011-07-01

    Silica melts are reflected in many different industrial and natural processes such as slags in steel production and gasification of coal, glass in the glass making industry, lava in the volcanology and in lots of other fields. Rheological properties like the viscosity of this silica melts are really important in all of these processes. A general and good working viscosity model would help all scientists and engineers, who have to simulate and optimise these processes. First, it is important to have the possibility to measure viscosities of slags. As part of this PhD thesis a new high-temperature high-pressure rotational viscosimeter is developed for measurements up to {>=}1600 C and 20 bar. Particularly in relation to the coal gasification process this two parameters are really important, because coal gasification occurs under high temperatures and high pressures. With this new viscosimeter it is possible to measure slag viscosities under realistic gasification conditions. To show that the new viscosimeter works quite good viscosity measurements of four real slags have been done. The influence of pressure and atmosphere on viscosity have been examined. The measurements are also compared with different viscosity models. The Arrhenius- and Weymann-Equation have been determined and the correlation between viscosity and basicity of the slag has been evaluated. In the second part of the Phd thesis a new viscosity model is developed. The model is based on the structure inside the slag and consists in existing thermodynamic models. After a detailed literature research the model is developed for the SiO{sub 2}-Al{sub 2}O{sub 3}-Na{sub 2}O-K{sub 2}O system. The quality of this new model is estimated by comparing calculated viscosity values with measurements found during the literature research. The new model is also compared with other existing models for viscosity calculation.

  12. Slag corrosion of gamma aluminium oxynitride

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xidong; Li Wen Chao [Beijing Univ. of Science and Technology, BJ (China). Dept. of Physical Chemistry of Metals; Sichen Du; Seetharaman, S. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Materials Science and Technology

    2002-03-01

    Corrosion of {gamma}-aluminium oxynitride (AlON) by CaO-MgO-''FeO''-Al{sub 2}O{sub 3}-SiO{sub 2} melts corresponding to blast furnace slag was examined from 1693 to 1753 K under static and forced convection conditions. An intermediate layer was observed between the unreacted oxynitride and slag. After a certain time interval, the rate of the growth of this layer was found to be equal to the rate of the dissolution of the layer. Slag corrosion of AlON is a strongly thermally activated process, the overall activation energy being 1002 kJ/mol. The rate of corrosion was found to be significantly enhanced by the addition of ''FeO''. (orig.)

  13. Report for fiscal 1994 by Coal Gasification Committee; 1994 nendo sekitan gas ka iinkai hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    Summarized in this report is the material already distributed concerning the program for modifying the Nakoso 200t/d pilot plant entrained bed coal gasification furnace. The program aims to verify the overall suitability for power generation use of the air-blow pressurized 2-chamber 2-stage flow entrained bed gasification furnace. Although each specific feature of gasification furnace performance is found to be satisfactory, yet a 100% operation and extended continuous operation remain to be accomplished. Slagging is a phenomenon of ash grains in high-temperature gas adhering to and growing on the furnace walls to block up the furnace to eventually disable the furnace from continuous operation. In view of past achievements and test results, it is found that slagging is closely related to the behavior of floating or molten ash and to the transition temperature range. Various slagging measures have been taken for the current gasification furnace, but they prove to be ineffective. Some drastic measures need to be implemented for improvement. Under study using model furnaces and test furnaces are the reduction of slag generation at its source (re-entrained slag), prevention of adhesion (untrapped slag), removal of slag, optimization of gyration in the furnace, modification of slag properties for enhanced discharge, optimization of the transition gas temperature range, and the modification of furnace dimensions. (NEDO)

  14. Coal and coke applied to metallurgy. Vol. 2. Carvao e coque aplicados a metalurgia

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, H.

    1983-01-01

    Papers include: coking; control of pollution from coking plants; handling and storage of coal; preparation of coal for coking; politics of the supply of coal; coke for blast furnaces; selective preparation and briquetting of coal for coking; cooling and drying of coke; preheating of coal for coking; formed coke.

  15. Studying properties of carbonaceous reducers and process of forming primary titanium slags

    Directory of Open Access Journals (Sweden)

    T. K. Balgabekov

    2014-10-01

    Full Text Available When smelting a rich titanium slag the most suitable are low-ash reducers, and the studies revealed the suitability for this purpose of special coke and coal. An important property of a reducer is its specific resistance. Therefore there were carried out studies for measuring electric resistance of briquettes consisting of ilmenite concentrate and different carbonaceous reducers. It is recommended to jointly smelt the briquetted and powdered burden (the amount of the powdered burden varies form 20 tо 50 %, this leads to the increase of technical-economic indicators of the process.

  16. New coal

    Energy Technology Data Exchange (ETDEWEB)

    1979-07-01

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

  17. Coal upgrading

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-10-15

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

  18. Low-rank coal research. Quarterly report, January--March 1990

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-01

    This document contains several quarterly progress reports for low-rank coal research that was performed from January-March 1990. Reports in Control Technology and Coal Preparation Research are in Flue Gas Cleanup, Waste Management, and Regional Energy Policy Program for the Northern Great Plains. Reports in Advanced Research and Technology Development are presented in Turbine Combustion Phenomena, Combustion Inorganic Transformation (two sections), Liquefaction Reactivity of Low-Rank Coals, Gasification Ash and Slag Characterization, and Coal Science. Reports in Combustion Research cover Fluidized-Bed Combustion, Beneficiation of Low-Rank Coals, Combustion Characterization of Low-Rank Coal Fuels, Diesel Utilization of Low-Rank Coals, and Produce and Characterize HWD (hot-water drying) Fuels for Heat Engine Applications. Liquefaction Research is reported in Low-Rank Coal Direct Liquefaction. Gasification Research progress is discussed for Production of Hydrogen and By-Products from Coal and for Chemistry of Sulfur Removal in Mild Gas.

  19. γ-ray activity in bituminous, subbituminous and lignite coals

    International Nuclear Information System (INIS)

    Barber, D.E.; Giorgio, H.R.

    1977-01-01

    Specimens of three different types of coal from four different geographical locations (Montana, North Dakota, Illinois and Pennsylvania) were examined by γ-ray spectrometry. Some samples were ashed in a muffle furnace. Other samples included pulverized coal, slag and fly ash from an electric power generating station. Activity from the 232 Th and 238 U series was present in all samples. Activity varied widely depending upon the source of the coal. The results indicate a need for additional examination of activity in coal to: (1) establish more precisely the relative environmental impact of coal-fired power stations compared with nuclear ones, (2) indicate the degree of sophistication required in environmental surveillance programs involving areas where both nuclear and coal-fired power stations are operational, and (3) determine the occupational exposure risks in mining operations. (author)

  20. Applicability of slags as waste forms for hazardous waste

    International Nuclear Information System (INIS)

    Bates, J.K.; Buck, E.C.; Dietz, N.L.; Wronkiewicz, D.J.; Feng, X.; Whitworth, C.; Filius, K.; Battleson, D.

    1994-01-01

    Slags, which are a combination of glassy and ceramic phases, were produced by the Component Development and Integration Facility, using a combination of soil and metal feeds. The slags were tested for durability using accelerated test methods in both water vapor and liquid water for time periods up to 179 days. The results indicated that under both conditions there was little reaction of the slag, in terms of material released to solution, or the reaction of the slag to form secondary mineral phases. The durability of the slags tested exceeded that of current high-level nuclear glass formulations and are viable materials, for waste disposal

  1. Simulation of slag control for the Plasma Hearth Project

    International Nuclear Information System (INIS)

    Power, M.A.; Carney, K.P.; Peters. G.G.

    1996-01-01

    The goal of the Plasma Hearth Project is to stabilize alpha-emitting radionuclides in a vitreous slag and to reduce the effective storage volume of actinide-containing waste for long-term burial. The actinides have been shown to partition into the vitreous slag phase of the melt. The slag composition may be changed by adding glass-former elements to ensure that this removable slag has the most desired physical and chemical properties for long-term burial. A data acquisition and control system has been designed to regulate the composition of five elements in the slag

  2. Production of highly porous glass-ceramics from metallurgical slag, fly ash and waste glass

    Directory of Open Access Journals (Sweden)

    Mangutova Bianka V.

    2004-01-01

    Full Text Available Glass-ceramics composites were produced based on fly-ash obtained from coal power stations, metallurgical slag from ferronickel industry and waste glass from TV monitors, windows and flasks. Using 50% waste flask glass in combination with fly ash and 20% waste glass from TV screens in combination with slag, E-modulus and bending strength values of the designed systems are increased (system based on fly ash: E-modulus from 6 to 29 GPa, and bending strength from 9 to 75 MPa. The polyurethane foam was used as a pore creator which gave the material porosity of 70(5% (fly ash-glass composite and a porosity of 65( 5% (slag-glass composite. E-modulus values of the designed porous systems were 3.5(1.2 GPa and 8.1(3 GPa, while the bending strength values were 6.0(2 MPa and 13.2(3.5 MPa, respectively. These materials could be used for the production of tiles, wall bricks, as well as for the construction of air diffusers for waste water aeration.

  3. Thermodynamic properties of chromium bearing slags and minerals. A review

    Energy Technology Data Exchange (ETDEWEB)

    Xiao Yanping; Holappa, L.

    1996-12-31

    In this report, the thermodynamic properties of chromium bearing slags and minerals were reviewed based on the available information in the literature. It includes the analysing methods for oxidation state of chromium in slags, oxidation state of chromium and activities of chromium oxides in slags and minerals. The phase diagrams of chromium oxide systems and chromium distributions between slag and metal phases are also covered ill this review. Concerning the analysing methods, it was found that most of the available approaches are limited to iron free slag systems and the sample preparation is very sensitive to the analysing results. In silicate slags under reducing atmosphere, divalent and trivalent chromium co-exist in the slags. It is agreed that the fraction of divalent chromium to total chromium increases with higher temperature, lower slag basicity and oxygen potential. For the slags under oxidising atmosphere, trivalent, pentavalent and hexavalent states were reported to be stable. The activities of CrO and CrO{sub 1.5} were concluded to have positive deviation from ideal solution. Slag basicity has a positive effect and temperature has a negative effect on the activities of chromium oxides. The phase diagrams of the Cr-O, binary, and ternary chromium containing oxide systems have been examined systematically. The analysis shows that the data on the quaternary and quinary systems are insufficient, and require further investigation. The most important features of the chromium containing silicate slags are the large miscibility gaps and the stability of the chromite spinel. (orig.) (76 refs.)

  4. Modelling of slag emulsification and slag reduction in CAS-OB process

    OpenAIRE

    Sulasalmi, P. (Petri)

    2016-01-01

    Abstract Composition Adjustment by Sealed argon bubbling – Oxygen Blowing (CAS-OB) process is a ladle treatment process that was developed for chemical heating and alloying of steel. The main stages of the process are heating, (possible) alloying and reduction of slag. The CAS-OB process aims for homogenization and control of the composition and temperature of steel. In this dissertation, a mathematical reaction model was developed for the slag reduction stage of the CAS-OB process. Sl...

  5. Characteristics and environmental aspects of slag: a review

    Science.gov (United States)

    Piatak, Nadine M.; Parsons, Michael B.; Seal, Robert R.

    2015-01-01

    Slag is a waste product from the pyrometallurgical processing of various ores. Based on over 150 published studies, this paper provides an overview of mineralogical and geochemical characteristics of different types of slag and their environmental consequences, particularly from the release of potentially toxic elements to water. This chapter reviews the characteristics of both ferrous (steel and blast furnace Fe) and non-ferrous (Ag, Cu, Ni, Pb, Sn, Zn) slag. Interest in slag has been increasing steadily as large volumes, on the order of hundreds of millions of tonnes, are produced annually worldwide. Research on slag generally focuses on potential environmental issues related to the weathering of slag dumps or on its utility as a construction material or reprocessing for secondary metal recovery. The chemistry and mineralogy of slag depend on the metallurgical processes that create the material and will influence its fate as waste or as a reusable product.

  6. Coal-92

    International Nuclear Information System (INIS)

    Hillring, B.; Sparre, C.

    1992-11-01

    Swedish consumption of coal and coke during 1991 and trends in technology, environment and market aspects of coal use are reported. Steam coal use in the heating sector was unchanged from 1991, 1.2 Mtons. Reduced consumption in smaller district heating units (due to conversion to biofuels and gas) was compensated by increased use for power generation in cogeneration plants. Coal consumption in industry fell 0.10 Mton to 0.84 Mton due to lower production in one industry branch. Import of steam coal was 1.1 Mton (down 0.5 Mton from 1990) since new rules for strategic reserves allowed a reduction of stocks. During the last five years stocks have been reduced by 2 Mtons. Import of metallurgical coal was 1.6 Mton, unchanged from 1990. The report also gives statistics for the coal using plants in Sweden, on coal R and D, and on emission laws for coal firing. (9 tabs., 2 figs.)

  7. Preliminary study of tin slag concrete mixture

    Science.gov (United States)

    Hashim, Mohd Jamil; Mansor, Ishak; Pauzi Ismail, Mohamad; Sani, Suhairy; Azmi, Azhar; Sayuti, Shaharudin; Zaidi Ibrahim, Mohd; Adli Anuar, Abul; Rahim, Abdul Adha Abdul

    2018-01-01

    The study focuses on practices to facilitate tin smelting industry to reduce radioactive waste product (Tin Slag) by diluting its radioactivity to a safe level and turning it to a safer infrastructural building product. In the process the concrete mix which include Portland cement, sand, tin slag, water and plasticizer are used to produce interlocking brick pavements, piles and other infrastructural products. The mixing method follows DOE (UK) standard method of mixing targeted at in selected compressive strength suitable for its function and durability. A batching machine is used in the mixing and six test cubes are produced for the test. The testing equipment used are a compressional machine, ultrasonic measurement and a Geiger Muller counter to evaluate of the concrete mix to find the lowest emission of radiation surface dose without compromising the strength of concrete mix. The result obtained indicated the radioactivity of tin slag in the mixing process has reduced to background level that is 0.5μSv/h while the strength and workability of the concrete has not been severely affected. In conclusion, the concrete mix with tin slag has shown the potential it can be turned into a safe beneficial infrastructural product with good strength.

  8. Coal 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    ACR's Coal 1992, the successor to the ACR Coal Marketing Manual, contains a comprehensive set of data on many aspects of the Australian coal industry for several years leading up to 1992. Tables and text give details of coal production and consumption in New South Wales, Queensland and other states. Statistics of the Australian export industry are complemented by those of South Africa, USA, New Zealand, Canada, Indonesia, China, Colombia, Poland and ex-USSR. Also listed are prices of Australian coking and non-coking coal, Australian coal stocks (and those of other major countries), loading port capacities, freight rates and coal quality requirements (analysis of coals by brand and supplier). A listing of Australian coal exporting companies is provided. A description of the spot Coal Screen Dealing System is given. World hard coal imports are listed by country and coal imports by major Asian countries tabulated. A forecast of demand by coal type and country up to the year 2000 is included.

  9. Balance of natural radionuclides in the brown coal based power generation and harmlessness of the residues and side product utilization

    International Nuclear Information System (INIS)

    Schulz, Hartmut; Kunze, Christian; Hummrich, Holger

    2017-01-01

    During brown coal combustion a partial enrichment of natural radionuclides occurs in different residues. Residues and side product from brown coal based power generation are used in different ways, for example filter ashes and gypsum from flue gas desulfurization facilities are used in the construction materials fabrication and slags for road construction. Detailed measurement and accounting of radionuclides in the mass throughputs in coal combustion power plants have shown that the utilized gypsum and filter ashes are harmless in radiologic aspects.

  10. Coal pump

    Science.gov (United States)

    Bonin, John H.; Meyer, John W.; Daniel, Jr., Arnold D.

    1983-01-01

    A device for pressurizing pulverized coal and circulating a carrier gas is disclosed. This device has utility in a coal gasification process and eliminates the need for a separate collection hopper and eliminates the separate compressor.

  11. Reprocessing of metallurgical slag into materials for the building industry

    International Nuclear Information System (INIS)

    Pioro, L.S.; Pioro, I.L.

    2004-01-01

    Several methods of reprocessing metallurgical (blast furnace) slag into materials for the building industry, based on melting aggregates with submerged combustion, were developed and tested. The first method involves melting hot slag with some additives directly in a slag ladle with a submerged gas-air burner, with the objective of producing stabilized slag or glass-ceramic. The second method involves direct draining of melted slag from a ladle into the slag receiver, with subsequent control of the slag draining into the converter where special charging materials are added to the melt, with the objective of producing glass-ceramic. A third method involves melting cold slag with some additives inside a melting converter with submerged gas-air burners, with the objective of producing glass-ceramic fillers for use in road construction. Specific to the melting process is the use of a gas-air mixture with direct combustion inside the melt. This feature provides melt bubbling to help achieve maximum heat transfer from combustion products to the melt, improve mixing (and therefore homogeneity of the melt), and increases the rate of chemical reactions. The experimental data for different aspects of the proposed methods are presented. The reprocessed blast-furnace slag in the form of granules can be used as fillers for concretes, asphalts, and as additives in the production of cement, bricks and other building materials. As well, reprocessed blast-furnace slag can be poured into forms for the production of glass-ceramic tiles

  12. Influences of Steelmaking Slags on Hydration and Hardening of Concretes

    Science.gov (United States)

    Kirsanova, A. A.; Dildin, A. N.; Maksimov, S. P.

    2017-11-01

    It is shown that the slag of metallurgical production can be used in the construction industry as an active mineral additive for concrete. This approach allows us to solve environmental problems and reduce costs for the production of binder and concrete simultaneously. Most often slag is used in the form of a filler, an active mineral additive or as a part of a binder for artificial conglomerates. The introduction of slag allows one to notice a part of the cement, to obtain concretes that are more resistant to the impact of aggressive sulfate media. The paper shows the possibility of using recycled steel-smelting slags in the construction industry for the production of cement. An assessment was made of their effect on the hydration of the cement stone and hardening of the concrete together with the plasticizer under normal conditions. In the process of work, we used the slag of the Zlatoust Electrometallurgical Factory. Possible limitations of the content of steel-slag slag in concrete because of the possible presence of harmful impurities are shown. It is necessary to enter slag in conjunction with superplasticizers to reduce the flow of water mixing. Slags can be used as a hardening accelerator for cement concrete as they allow one to increase the degree of cement hydration and concrete strength. It is shown that slags can be used to produce fast-hardening concretes and their comparative characteristics with other active mineral additives are given.

  13. Suitability of leaching test methods for fly ash and slag: A review

    Directory of Open Access Journals (Sweden)

    Manoj Kumar Tiwari

    2015-10-01

    Full Text Available Fly ash and slag leachate pollution can be of great environmental concern due to generation of these wastes in huge quantities from their respective industrial units, mainly coal-based thermal power plants and iron and steel plants. For simulation of natural leaching in laboratory, various leaching methods are available, but selection of a method that can exactly simulate the real-life scenario for accurate estimation of various pollutants is challenging; particularly, the heavy metals present and impact due to reuse or disposal of these wastes. For choosing the most suitable leaching method according to specific situation, one must primarily consider the chemical and physical properties of wastes, the composition of the source, age of waste disposal, and the climatic conditions of the disposal area. Since these factors may not be specified, a variety of leaching methods with relevant equipment have been proposed by researchers; that are based on their required information to particular conditions in absence of a prescribed protocol and non standardization of equipment. The present review is an attempt to investigate the suitable leaching method for coal fly ash and slag.

  14. Slagging gasifier refractories. A new pathway to longer refractory life

    Energy Technology Data Exchange (ETDEWEB)

    Schnake, Mark [Harbinson-Walker Refractories Company, Mexico, MO (United States)

    2013-07-01

    Solid fuel slagging gasification to convert coal or petroleum coke feedstocks into syngas has rapidly evolved over the last 25 years. The gasifier is a high temperature, high pressure reaction chamber. Operating temperatures are between 1250 and 1575 C. Pressures will be between 20.4 and 68 atm. Syngas has been typically used for chemical feedstocks, fuel for power plants, or for steam and hydrogen generation in other industrial applications. Ash which comes from the solid fuel during gasification has many impurities. It melts during the gasifier reactor operation forming a liquid that penetrates the refractory lining. Given time, the refractory will wear away from thermal spalling, structural spalling, or overheating of the refractory. In some cases, all three wear mechanisms are seen in the same gasifier lining. Industry users have identified refractory life as one major limiting factor in worldwide use of this technology. Users have stated if the refractory liner can increase on-line availability of the gasifier operation, more industry acceptance of this technology is possible. Harbison-Walker Refractories Company will review destructive factors affecting lining life and discuss new refractory materials that have dramatically increased gasifier lining life and reliability. New refractory materials will be presented and supported by field trial results and post mortem analysis.

  15. Cooling techniques

    International Nuclear Information System (INIS)

    Moeller, S.P.

    1994-01-01

    After an introduction to the general concepts of cooling of charged particle beams, some specific cooling methods are discussed, namely stochastic, electron and laser cooling. The treatment concentrates on the physical ideas of the cooling methods and only very crude derivations of cooling times are given. At the end three other proposed cooling schemes are briefly discussed. (orig.)

  16. Leaching of heavy metals from steelmaking slags

    Directory of Open Access Journals (Sweden)

    Gomes, J. F. P

    2006-12-01

    Full Text Available Leaching tests with EAF and Ladle slags were performed, using a flow through test and the standard batch test DIN 38414-S4. The previous method was used to simulate the leaching behaviour of steel slags under landfill. The chemical analysis of the leachates during this period shows, in general, for both types of slag, an increase of heavy metal releases with ageing. Standard test method DIN 38414-S4 was used to evaluate leachability of heavy metals by water in unprocessed slags. After more than one year of trials, slag samples submitted to these trials presented very low total leaching levels. The most extracted elements are calcium and magnesium. Nevertheless, in flow-through test, calcium and magnesium leached from solid slags are below 0.5% and all other metals below 0.1%. Leachates obtained with DIN 38414-S4 present, as expected, higher leaching values; however, these are inferior to 5 % (Ca and 1% (other elements.

    Este articulo contiene los resultados obtenidos en ensayos de lixiviación de escorias de acero (horno electrico y cuchara ejecutados siguiendo la metodologia de flujo dinámico así como el ensayo normalizado DIN 38414-S4. El primer ensayo intenta simular el comportamiento de lixiviación de las escorias en vertedero. Para las escorias ensayadas se han complementado los ensayos con el análisis químico de los lixiviados y se ha verificado un aumento de la liberación de metales pesados. El ensayo DIN 38414-S4 se ha utilizado para evaluar la lixiviación por agua de metales pesados, en muestras de escorias originales. Despues de un año de ensayos, se han observado niveles muy bajos de lixiviación. Los elementos mas lixiviados han sido calcio y magnesio. No obstante, en los ensayos de flujo dinámico, el calcio y el magnesio lixiviados de las escorias sólidas era menor de 0,5% y el resto de los otros metales era inferior a 0,1%. Los lixiviados obtenidos con el ensayo DIN 38414-S4 presentan, como era de esperar, valores

  17. Coal ash parameters by neutron activation

    International Nuclear Information System (INIS)

    Chrusciel, Edward; Chau, N.D.; Niewodniczanski, J.W.

    1994-01-01

    The coal parameters, ash content and ash slagging index, may be strongly related to the chemical composition of mineral impurities in coal. Based on this assumption the authors have examined the feasibility of neutron activation techniques, both as a laboratory and a well logging method, by recording induced γ-rays in the two energy intervals with the help of a scintillation γ-ray spectrometer. Results from the Upper Silesiab Coal Basin have shown that the method can be used to evaluate the ash content and ash fusion temperature, both in the laboratory and in well logging; the corresponding mean standard deviations being 1.5 wt% and 35 o C; and 3 wt% and 45 o C respectively. (author)

  18. HCl removal using cycled carbide slag from calcium looping cycles

    International Nuclear Information System (INIS)

    Xie, Xin; Li, Yingjie; Wang, Wenjing; Shi, Lei

    2014-01-01

    Highlights: • Cycled carbide slag from calcium looping cycles is used to remove HCl. • The optimum temperature for HCl removal of cycled carbide slag is 700 °C. • The presence of CO 2 restrains HCl removal of cycled carbide slag. • CO 2 capture conditions have important effects on HCl removal of cycled carbide slag. • HCl removal capacity of carbide slag drops with cycle number rising from 1 to 50. - Abstract: The carbide slag is an industrial waste from chlor-alkali plants, which can be used to capture CO 2 in the calcium looping cycles, i.e. carbonation/calcination cycles. In this work, the cycled carbide slag from the calcium looping cycles for CO 2 capture was proposed to remove HCl in the flue gas from the biomass-fired and RDFs-fired boilers. The effects of chlorination temperature, HCl concentration, particle size, presence of CO 2 , presence of O 2 , cycle number and CO 2 capture conditions in calcium looping cycles on the HCl removal behavior of the carbide slag experienced carbonation/calcination cycles were investigated in a triple fixed-bed reactor. The chlorination product of the cycled carbide slag from the calcium looping after absorbing HCl is not CaCl 2 but CaClOH. The optimum temperature for HCl removal of the cycled carbide slag from the carbonation/calcination cycles is 700 °C. The chlorination conversion of the cycled carbide slag increases with increasing the HCl concentration. The cycled carbide slag with larger particle size exhibits a lower chlorination conversion. The presence of CO 2 decreases the chlorination conversions of the cycled carbide slag and the presence of O 2 has a trifling impact. The chlorination conversion of the carbide slag experienced 1 carbonation/calcination cycle is higher than that of the uncycled calcined sorbent. As the number of carbonation/calcination cycles increases from 1 to 50, the chlorination conversion of carbide slag drops gradually. The high calcination temperature and high CO 2

  19. Investigation and assessment of lead slag concrete as nuclear shields

    International Nuclear Information System (INIS)

    Zaghloul, Y.R.

    2009-01-01

    The present work is concerned with the efficiency of heavy weight concrete as a shielding material in constructing nuclear installations as well as for radioactive wastes disposal facilities.In this context, lead slag was used as a replacement for fine aggregates in heavy concrete shields that include local heavy weight aggregates (namely; barite and ilmenite) as well as normal concrete includes dolomite and sand as coarse and fine aggregates, as a reference. The effect of different percentages of lead slag was investigated to assess the produced lead slag concrete as a nuclear shielding material. The different properties (physical, mechanical and nuclear) of the produced lead slag concrete were investigated. The results obtained showed that increasing the lead slag percentage improving the investigated properties of the different concrete mixes. In addition, ilmenite concrete with 20% lead slag showed the best results for all the investigated properties.

  20. Moderate Dilution of Copper Slag by Natural Gas

    Science.gov (United States)

    Zhang, Bao-jing; Zhang, Ting-an; Niu, Li-ping; Liu, Nan-song; Dou, Zhi-he; Li, Zhi-qiang

    2018-01-01

    To enable use of copper slag and extract the maximum value from the contained copper, an innovative method of reducing moderately diluted slag to smelt copper-containing antibacterial stainless steel is proposed. This work focused on moderate dilution of copper slag using natural gas. The thermodynamics of copper slag dilution and ternary phase diagrams of the slag system were calculated. The effects of blowing time, temperature, matte settling time, and calcium oxide addition were investigated. The optimum reaction conditions were identified to be blowing time of 20 min, reaction temperature of 1250°C, settling time of 60 min, CaO addition of 4% of mass of slag, natural gas flow rate of 80 mL/min, and outlet pressure of 0.1 MPa. Under these conditions, the Fe3O4 and copper contents of the residue were 7.36% and 0.50%, respectively.

  1. Nickel recovery from electric arc furnace slag by magnetic separation

    Directory of Open Access Journals (Sweden)

    Sakaroglou Marianna

    2017-01-01

    Full Text Available During the pyrometallurgical treatment of the nickel-bearing laterite in the plant of G.M.M. S.A. LARCO, slag is produced after treatment in electric-arc furnace (EAF that contains 0.10 to 0.20 % Ni. Taking into account the great quantity of slag produced per year, the recovery of nickel from the EAF slag will add benefits to the entire process. The target of the current work is to investigate the possibility of nickel recovery from EAF slag by magnetic separation. To meet the target, the effect of the following parameters was studied: grain size, magnetic field intensity, thickness of slag layer, moisture content, and re-grinding of the coarser slag particles. The results show that it is possible to obtain a magnetic product with nickel grade close to that of the primary raw material or even better, with sufficient nickel recovery.

  2. Relative radiation hazards of coal based and nuclear power plants

    International Nuclear Information System (INIS)

    Mishra, U.C.

    1983-04-01

    Coal, like most materials found in nature, contains trace quantities of naturally occurring radionuclides. However, low concentrations may become important if large quantities of coal are burnt in thermal power plants. Therefore a study was performed to determine the radioactivity in coal, in fly-ash and slag and assess the importance of radioactive emissions from thermal power plants. The results were compared to the radiological impact of nuclear power stations. Based on these data, theoretical estimates for the population living within 80km from power stations indicate that the collective dose commitments of coal-fired plants are one order of magnitude higher than those for BWR-type nuclear plants. Measurements taken in the vicinity of coal-fired plants were comparable to those for nuclear plants, i.e. within the range of variation of natural background radiation in India

  3. Studying the effect of thermal and acid exposure on alkali activated slag Geopolymer

    Directory of Open Access Journals (Sweden)

    Khater H.M.

    2014-04-01

    Full Text Available This article reports a study about thermal stability as well as acid resistance of geopolymer materials prepared from Ground Granulated Blast Furnace Slag (GGBFS, Air Cooled Slag (ACS, Silica fume (SF and cement kiln dust (CKD using 6% (weight of equal mix from alkaline sodium hydroxide and sodium silicate activators. Study of addition of ACS, SF and CKD as partial replacement of GGBFS is investigated so as to improve the mechanical and microstructural properties of geopolymer mixes. Compressive strength and SEM were utilized in these studies. Materials were prepared using water/binder of 0.30 at 38°C and 100% RH. Results showed that geopolymer materials prepared using alkali activated slag exhibit large changes in compressive strength with increasing the firing temperature from 300 to 1000°C and exhibit an enhancement in thermal stability as compared to concrete specimens. Materials prepared by replacing GGBFS by 15% ACS resist thermal deterioration up to 1000°C. It was suggested to be suitable for refractory insulation applications as well as for production of nuclear concrete reactors. On the other hand, geopolymer mixes exhibit low stability upon subjecting to different concentration from the mix of nitric and hydrochloric acid in equal ratio (1:1. Current studies of geopolymer microstructure were focused on the morphology as well as the relationship between compositions and mechanical properties.

  4. Kinetics and physico-chemical properties of alkali activated blast-furnace slag/basalt pastes

    Directory of Open Access Journals (Sweden)

    H. El Didamony

    2012-12-01

    Full Text Available Granulated blast-furnace slag (GBFS is a by-product of the metallurgical industry and consists mainly of lime and calcium–magnesium aluminosilicates that defined as the glassy granular material formed by rapid cooling of molten slag with excess water resulting in an amorphous structure. Alkali-activated slag (AAS binders have taken a great interest from researchers due to its manufacturing process which has important benefits from the point of view of the lower energy requirements and lower emission of greenhouse gases with respect to the manufacturing of Portland cement. In this study, GBFS was replaced by 20, 40 and 60 wt.% of basalt activated by 6 wt.% of alkali mixture composed of 1:1 sodium hydroxide (SH and liquid sodium silicate (LSS mixed with sea water and cured in 100% relative humidity up to 90 days. The physic-chemical parameters were studied by determination of setting time, combined water content, bulk density and compressive strength. As the amount of basalt increases the setting time as well as compressive strength decreases while the bulk density increases. The compressive strength values of dried pastes are greater than those of saturated pastes. The hydrated products are identified by TGA/DTG analysis, IR spectroscopy and scanning electron microscopy (SEM.

  5. Reduction of chromium oxide from slags

    Directory of Open Access Journals (Sweden)

    Gutiérrez-Paredes, J.

    2005-12-01

    Full Text Available Experimental and theoretical work were performed to estimate the effect of slag basicity and amount of reducing agents on the reduction of chromium oxide from the slag which interacted with molten steel at 1,600 °C. The slag system contained CaO, MgO, SiO2, CaF2 and Cr2O3 together with Fe-alloys (Fe-Si and Fe-Si-Mg. The CaF2 and MgO contents in the slags were 10 mass % each; Cr2O3 was 25%. The amount of the ferroalloys ranged from 12.5 to 50 g per 100 g of slag. The (CaO+MgO/SiO2 ratio was held at 1 and 2. The Cr yield was determined using both Fe-alloys as reducing agents. Some estimations were made to determine the theoretical effect of temperature, slag basicity, (CaO+MgO/SiO2, and amount of reducing agents in the slag on the chromium recovery. The FACT (Facility for the Analysis of Chemical Thermodynamics computational package is used to determine the equilibrium between the slag and molten steel.

    En el presente trabajo se realiza un estudio teórico y experimental para determinar el efecto de la basicidad de la escoria y la cantidad de agentes reductores sobre la reducción de óxidos de cromo contenidos en la escoria, la cual está en contacto con acero líquido a 1.600 °C. La escoria se prepara con los reactivos CaO, MgO, SiO2, CaF2 y ferroaleaciones (Fe-Si y Fe-Si-Mg. Los contenidos de CaF2 y MgO en la escoria son de 10 %, cada uno, y el de Cr2O3 es 25 %. La cantidad de la ferroaleación varía de 12,5 a 50 g por cada 100 g de escoria. La relación (CaO+MgO/SiO2 tiene los valores de 1 y 2. Se determina la eficiencia de recuperación de cromo empleando los dos tipos de ferroaleaciones. Se realizaron cálculos para determinar el efecto teórico de la temperatura, la basicidad de la escoria, (CaO+MgO/SiO2, y la cantidad de agentes reductores sobre la reducci

  6. Outcomes of experimental researches on stainless steel decontamination from radioactive contamination using electric slag remelting method

    International Nuclear Information System (INIS)

    Vurim, A.D.; Pakhnitz, A.V.; Trukhachev, A.G.; Bukhtoyarov, O.I.; Goncharov, A.Ye.

    2003-01-01

    Full text: Institute of Atomic Energy prepared and conducted the experiments the purpose of researching a possibility of applying of stainless steel electric slag remelting for its decontamination from radioactive contamination. The activities were conducted at participating of the specialists of Kurgan State University, Kurgan (Russian Federation). A stand, which includes the electroslag furnace (power - 150 kW, current - to 3000 A) and auxiliary equipment (the system of common and special ventilation, system of remote control, system of parameters measuring and registering and others) was created to conduct the experiments. The properties of slag compositions were researched in the course of experiments preparation. Oxide (CaO-Al 2 O 3 - CaO-SiO 2 - MgO-B 2 O 3 ) and fluoride-oxide (CaF 2 -SiO 2 - MgF 2 -SiO 2 ) slag systems and some their modifications were chosen to research physical and chemical properties. Physical and chemical properties of the slag systems were experimentally researched and it included: measuring of surface tension using the method of maximum pressure in a gas bubble (at the same time density was measured); measuring of slag alloys electrical conductivity; measuring of melt volt-ampere characteristics. The flue tubes of high temperature reactor gas cooling KET technological channels were chosen as a source of radioactive contaminated stainless steel. This reactor is meant for testing of the fuel pin and FA of the nuclear pulse propulsion. Decontamination effect for all the remelted flue tubes was indirectly confirmed by the outcomes of measuring of radioactive radiation dose rate of the materials, extracted of the crystallizer after experiments finishing. The outcomes of the experiments show that the following processes pass at electroslag remelting of radioactively contaminated steel: uranium extraction from steel; uranium transfer from steel to slag; saving or insignificant modification of steel initial composition; radionuclides deposing

  7. Preliminary evaluation of a constructed wetland for treating extremely alkaline (pH 12) steel slag drainage.

    Science.gov (United States)

    Mayes, W M; Aumônier, J; Jarvis, A P

    2009-01-01

    High pH (> 12) leachates are an environmental problem associated with drainage from lime (CaO)-rich industrial residues such as steel slags, lime spoil and coal combustion residues. Recent research has highlighted the potential for natural ('volunteer') wetlands to buffer extremely alkaline influent waters. This appears ascribable to high CO(2) partial pressures in the wetland waters from microbial respiration, which accelerates precipitation of calcium carbonate (CaCO(3)), and the high specific surface area for mineral precipitation offered by macrophytes. The research presented here builds on this and provides preliminary evaluation of a constructed wetland built in March 2008 to buffer drainage from steel slag heaps in north-east England. The drainage water from the slag mounds is characterised by a mean pH of 11.9, high concentrations of Ca (up to 700 mg/L), total alkalinity (up to 800 mg/L as CaCO(3)) and are slightly brackish (Na = 300 mg/L; Cl = 400 mg/L) reflecting native groundwaters at this coastal setting. Documented calcite precipitation rates (mean of 5 g CaCO(3)/m(2)/day) from nearby volunteer sites receiving steel slag drainage were used to scale the constructed wetland planted with Phragmites australis; a species found to spontaneously grow in the vicinity of the discharge. Improved performance of the wetland during summer months may at least in part be due to biological activity which enhances rates of calcite precipitation and thus lowering of pH. Secondary Ca-rich precipitates also serve as a sink for some trace elements present at low concentrations in the slag leachate such as Ni and V. The implications for scaling and applying constructed wetlands for highly alkaline drainage are discussed.

  8. Recovery of metal values from copper slag and reuse of residual secondary slag.

    Science.gov (United States)

    Sarfo, Prince; Das, Avimanyu; Wyss, Gary; Young, Courtney

    2017-12-01

    Resource and environmental factors have become major forces in mining and metallurgy sectors driving research for sustainability purposes. The concept of zero-waste processing has been gaining ground readily. The scant availability of high quality raw materials has forced the researchers to shift their focus to recycling while the exceedingly stringent environmental regulations have forced researchers to explore new frontiers of minimizing/eliminating waste generation. The present work is aimed at addressing both aspects by employing recycling to generate wealth from copper slag and producing utilizable materials at the same time thus restoring the ecosystem. Copper slag was characterized and processed. The pyro-metallurgical processing prospects to generate utilizable materials were arrived at through rigorous thermodynamic analysis. Carbothermal reduction at elevated temperature (near 1440°C) helped recover a majority of the metal values (e.g., Fe, Cu and Mo) into the iron-rich alloy product which can be a feed material for steel making. On the other hand, the non-metallic residue, the secondary slag, can be used in the glass and ceramic industries. Reduction time and temperature and carbon content were shown to be the most important process variables for the reaction which were optimized to identify the most favored operating regime that maximizes the metal recovery and simultaneously maximizes the hardness of the secondary slag and minimizes its density, the two major criteria for the secondary slag product to be utilizable. The flux addition level was shown to have relatively less impact on the process performance if these are maintained at an adequate level. The work established that the copper slag, a waste material, can be successfully processed to generate reusable products through pyrometallurgical processing. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Characterization of Rare Earth Element Minerals in Coal Utilization Byproducts

    Energy Technology Data Exchange (ETDEWEB)

    Montross, Scott N. [Oak Ridge Inst. for Science and Education (ORISE), Oak Ridge, TN (United States); Verba, Circe A. [National Energy Technology Lab. (NETL), Albany, OR (United States). Research Innovation Center; Collins, Keith [National Energy Technology Lab. (NETL), Albany, OR (United States). Research Innovation Center

    2017-07-17

    The United States currently produces over 100 million tons of coal utilization byproducts (CUB) per year in the form of fly ash, bottom ash, slag, and flue gas (American Coal Ash Association (ACCA), 2015). But this “waste material” also contains potentially useful levels of rare earth elements (REE). Rare earth elements are crucial for many existing and emerging technologies, but the U.S. lacks a domestic, sustainable REE source. Our project explored the possibility of developing a supply of REEs for U.S. technologies by extracting REEs from CUBs. This work offers the potential to reduce our dependence on other countries for supply of these critical elements (NETL, REE 2016 Project Portfolio). Geologic and diagenetic history, industrial preparation methods, and the specific combustion process all play major roles in the composition of CUB. During combustion, inorganic mineral phases of coal particles are fluidized at temperatures higher than 1400oC, so inorganic mineral materials are oxidized, fused, disintegrated, or agglomerated into larger spherical and amorphous (non-crystalline) particles. The original mineralogy of the coal-containing rock and heating/cooling of the material significantly affects the composition and morphology of the particles in the combustion byproduct (Kutchko and Kim, 2006). Thus, different types of coal/refuse/ash must be characterized to better understand mineral evolution during the combustion process. Our research focused on developing a working model to address how REE minerals behave during the combustion process: this research should help determine the most effective engineering methods for extracting REEs from CUBs. We used multimodal imaging and image processing techniques to characterize six rock and ash samples from different coal power plants with respect to morphology, grain size, presence of mineral phases, and elemental composition. The results of these characterization activities provided thresholds for realizing the

  10. Comparative results of copper flotation from smelter slag and granulated smelter slag

    OpenAIRE

    Milanović, Dragan; Stanujkić, Dragiša; Ignjatović, Miroslav R.

    2013-01-01

    Smelter slag is obtained in the process of metallurgical converting of copper concentrate in the Smelter Plant in Bor, Serbia. Today, the reserves of this material are evaluated at about more of a year, with the average copper content of 0.6-0.9%. Production of copper concentrate by flotation of smelter slag has started in 2001. Flotation concentrate goes to the Copper Smelter once more for production of copper cathodes and the rough flotation tailings go to the flotation tailing dump. Copper...

  11. Formation of the gaseous phase of impurity elements from coal combustion at a thermal power plant

    International Nuclear Information System (INIS)

    Kizil'shtein, L.Ya.; Levchenko, S.V.; Peretyakt'ko, A.G.

    1991-01-01

    Data are reported on the distribution of impurity elements in their principal carriers: organic matter, iron sulfides, and clays. Tests with high-temperature combustion of coals and argillites indicate that elements associated with clay minerals largely remain in ash and slag. They do not pass to the gas phase - a factor to be considered in assessment of environmental impact from thermal power plants and specification of toxic concentration levels of impurity elements in coal

  12. Australian coal

    Energy Technology Data Exchange (ETDEWEB)

    1985-11-01

    Total export shipments of coal in Australia in the year ending June 30 1985 reached a record of 83.8 Mt. The export trade is expected to bring in an income of 4 billion Australian dollars in the current year making coal Australia's biggest revenue-earning export commodity. This article presents a brief overview of the Australian coal industry with production and export statistics and information on major open pit and underground mines.

  13. Healy Clean Coal Project: Healy coal firing at TRW Cleveland Test Facility. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, T.; Petrill, E.; Sheppard, D.

    1991-08-01

    A test burn of two Alaskan coals was conducted at TRW`s Cleveland test facility in support of the Healy Clean Coal Project, as part of Clean Coal Technology III Program in which a new power plant will be constructed using a TRW Coal Combustion System. This system features ash slagging technology combined with NO{sub x} and SO{sub x} control. The tests, funded by the Alaska Industrial Development and Export Authority (AIDEA) and TRW, were conducted to verify that the candidate Healy station coals could be successfully fired in the TRW coal combustor, to provide data required for scale-up to the utility project size requirements, and to produce sufficient flash-calcined material (FCM) for spray dryer tests to be conducted by Joy/NIRO. The tests demonstrated that both coals are viable candidates for the project, provided the data required for scale-up, and produced the FCM material. This report describes the modifications to the test facility which were required for the test burn, the tests run, and the results of the tests.

  14. Healy Clean Coal Project: Healy coal firing at TRW Cleveland Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, T.; Petrill, E.; Sheppard, D.

    1991-08-01

    A test burn of two Alaskan coals was conducted at TRW's Cleveland test facility in support of the Healy Clean Coal Project, as part of Clean Coal Technology III Program in which a new power plant will be constructed using a TRW Coal Combustion System. This system features ash slagging technology combined with NO{sub x} and SO{sub x} control. The tests, funded by the Alaska Industrial Development and Export Authority (AIDEA) and TRW, were conducted to verify that the candidate Healy station coals could be successfully fired in the TRW coal combustor, to provide data required for scale-up to the utility project size requirements, and to produce sufficient flash-calcined material (FCM) for spray dryer tests to be conducted by Joy/NIRO. The tests demonstrated that both coals are viable candidates for the project, provided the data required for scale-up, and produced the FCM material. This report describes the modifications to the test facility which were required for the test burn, the tests run, and the results of the tests.

  15. Coal - 96

    International Nuclear Information System (INIS)

    Sparre, C.

    1996-09-01

    The report deals mainly with coal consumption, but also gives some information about technology, environmental aspects and markets. Data have been collected by questionnaires or via telephone. The use of steam coal for heating was 0.8 Mtons (down 20% from 1994). Cogeneration plants were the main users. Taxes and environmental reasons cause a reduction of the coal use that will probably continue the next years. Use of steam coal in industry has been constant at a level of 0.7 Mtons. The import of metallurgical coal rests constant at a level of 1.6 Mtons. 1.2 Mtons of coke was produced, and 0.3 Mtons imported. The PFBC-plant at Vaertan, Stockholm used 0.13 Mtons of coal, while some coal fired power plants have been converted to peat and wood fuels. The average price of steam coal imported to Sweden in 1995 was 333 SEK/ton, 6% higher than in 1994. The contract prices for delivery 1996 are about the same as at the end of 1995. All cogeneration plants have some sort of SO 2 removal system, mostly wet-dry. The largest plant, at Vaesteraas, has recently invested in a SCR system for NO x removal. Most other plants are using low NO x burners or SNCR systems, based on ammonia or urea, which reduce the emissions 50 - 70%. Some statistic about the world coal market is also given in the report

  16. Venezuelan coal

    International Nuclear Information System (INIS)

    Vazquez, L.U.

    1991-01-01

    The existence of coal deposits in Venezuela has been known since the early nineteenth century, when the Naricual Mines were discovered in the State of Anzoategui Eastern Venezuela. Through the years the Venezuelan coal business had its ups and downs, but it was not until 1988 that we could properly say that our coal began to play a role in the international market. This paper reports that it is only now, in the nineties, that Venezuelan coal projects have come under a planning, promotional and developmental policy preparing the ground for the great projects Venezuela will have in the not-too-distant future

  17. Role of coal combustion products in sustainable construction materials

    Energy Technology Data Exchange (ETDEWEB)

    Naik, T.R.; Siddique, R.; Vaniker, S. [University of Wisconsin-Milwaukee, Milwaukee, WI (USA). UWM Center for Products Utilization, College of Engineering and Applied Science

    2003-07-01

    The paper describes various coal combustion products, CCPs produced in the process of power generation. These include fly ash, bottom ash, boiler slag and flue gas desulfurization products. Typical test protocol used for testing, analysis and evaluation of CCPs, as well as the current best recycling use options for these materials are discussed. Materials, productions, properties, and potential applications in the manufacture of emerging materials for sustainable construction, as well as environmental impact are also briefly discussed. 47 refs., 16 figs., 8 tabs.

  18. Coal and recycling mark the way forward

    Energy Technology Data Exchange (ETDEWEB)

    Bignell, E.

    2000-11-01

    A report is given of this year's Mineral Engineering Society's annual conference held in Scarborough, UK. The themes of recycling and coal were chosen for the two days of technical presentations. Topics included the cleaning up of brown field sites; the use of recycled waste oxide to replace iron ore pellets for cooling furnaces in steel making; high pressure filtration of industrial mineral effluent; iron ore mining in Australia; screen development; the status of coal preparation technology, by RJB Mining; study of movement of material (to simulate coal) in a hopper; and a UK-Chinese project on reduction of sulphur in coal.

  19. Steel slag in hot mix asphalt concrete : final report

    Science.gov (United States)

    2000-04-01

    In September 1994, steel slag test and control sections were constructed in Oregon to evaluate the use of steel slag in hot mix asphalt concrete (HMAC). This report covers the construction and five-year performance of a pavement constructed with 30% ...

  20. ANALYSIS OF KINETICS OF CAST IRON ALLOYING THROUGH SLAG PHASE

    Directory of Open Access Journals (Sweden)

    O. S. Komarov

    2012-01-01

    Full Text Available The mechanism of cast iron alloying through slag phase due to use of nickel and copper oxides is considered and the analysis of kinetics regularity of alloying in case of absence of fuse in the form of milled cast-iron chips in slag and at their presence in it is carried out.

  1. The reaction of slag in cement, theory and computer modelling

    NARCIS (Netherlands)

    Chen, Wei; Brouwers, H.J.H.; Fischer, H.B

    2006-01-01

    For a better understanding of the performance of slag in concrete, evaluating the feasibility of using one certain type of slag and possible improvement of its use in practice, fundamental knowledge about its reaction and interaction with other constituents is important. While the researches on

  2. Modified DHTT Equipment for Crystallization Studies of Mold Slags

    Science.gov (United States)

    Kölbl, Nathalie; Harmuth, Harald; Marschall, Irmtraud

    2018-04-01

    The double hot thermocouple technique (DHTT) enables simulations of the temperature gradient at near-service conditions during continuous casting of steel. With the equipment applied so far, a rectangular slag film of even thickness often cannot be achieved. Further, the minimum temperature frequently lies within the slag film. Modified equipment can avoid these disadvantages via the following design features. The entire furnace chamber is heated to the selected temperature of the cold wire, and the minimum temperature is not located within the slag film. Furthermore, the shape of the heating wire is improved, which enables mounting of a thin, rectangular slag film between four platinum wires. This modification allows for investigations on transparent and translucent slags. So far, the results from DHTT investigations were represented via snapshots of the samples at certain experimental times. Therefore, appropriate methods for the graphical representation of the results were suggested: the maximum crystallinity, the time related to certain crystallinities with a dependence on the position within the slag film, and the crystal growth rate. The CaO-MgO-Al2O3-SiO2 slag investigated with this equipment was mineralogically examined additionally, and based on thermodynamic calculations, the allocation of temperatures to certain positions within the crystallized slag film was possible.

  3. Coal gasification in Europe

    International Nuclear Information System (INIS)

    Furfari, S.

    1992-01-01

    This paper first analyzes European energy consumption and supply dynamics within the framework of the European Communities energy and environmental policies calling for the increased use of natural gas, reduced energy consumption, promotion of innovative renewable energy technologies, and the reduction of carbon dioxide emissions. This analysis evidences that, while, at present, the increased use of natural gas is an economically and environmentally advantageous policy, as well as, being strategically sound (in view of Middle East political instability), fuel interchangeability, in particular, the option to use coal, is vital to ensure stability of the currently favourable natural gas prices and offer a locally available energy alternative to foreign supplied sources. Citing the advantages to industry offered by the use of flexible, efficient and clean gaseous fuels, with interchangeability, the paper then illustrates the cost and environmental benefits to be had through the use of high efficiency, low polluting integrated gasification combined-cycle power plants equipped to run on a variety of fuels. In the assessment of technological innovations in this sector, a review is made of some of the commercially most promising gasification processes, e.g., the British Gas-Lurgi (BGL) slagging gasifier, the high-temperature Winkler (HTW) Rheinbraun, and the Krupp Koppers (PRENFLO) moving bed gasifier processes

  4. Coal gasification in Europe

    Energy Technology Data Exchange (ETDEWEB)

    Furfari, S [Commissione delle Comunita' Europee, Bruxelles (Belgio). Direzione Generale dell' Energia, Direzione delle Tecnologie

    1992-02-01

    This paper first analyzes European energy consumption and supply dynamics within the framework of the European Communities energy and environmental policies calling for the increased use of natural gas, reduced energy consumption, promotion of innovative renewable energy technologies, and the reduction of carbon dioxide emissions. This analysis evidences that, while, at present, the increased use of natural gas is an economically and environmentally advantageous policy, as well as, being strategically sound (in view of Middle East political instability), fuel interchangeability, in particular, the option to use coal, is vital to ensure stability of the currently favourable natural gas prices and offer a locally available energy alternative to foreign supplied sources. Citing the advantages to industry offered by the use of flexible, efficient and clean gaseous fuels, with interchangeability, the paper then illustrates the cost and environmental benefits to be had through the use of high efficiency, low polluting integrated gasification combined-cycle power plants equipped to run on a variety of fuels. In the assessment of technological innovations in this sector, a review is made of some of the commercially most promising gasification processes, e.g., the British Gas-Lurgi (BGL) slagging gasifier, the high-temperature Winkler (HTW) Rheinbraun, and the Krupp Koppers (PRENFLO) moving bed gasifier processes.

  5. Coal summit II

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    Various papers were presented on world coal trade. Papers include: Poland as a producer and exporter of coal; the dynamics of world coal trade; Cerrejon coal production perspectives; present state of the Australian coal industry; present state of the EC coal market and future prospects; prospects of US coal exports to Europe; forecast of Italian coal supply and demand through 1990; statistics from coal transportation outlook; status of world coal ports.

  6. STOCHASTIC MODELING OF COMPRESSIVE STRENGTH OF PHOSPHORUS SLAG CONTENT CEMENT

    Directory of Open Access Journals (Sweden)

    Ali Allahverdi

    2016-07-01

    Full Text Available One of the common methods for quick determination of compressive strength as one of the most important properties for assessment of cement quality is to apply various modeling approaches. This study is aimed at finding a model for estimating the compressive strength of phosphorus slag content cements. For this purpose, the compressive strengths of chemically activated high phosphorus slag content cement prepared from phosphorus slag (80 wt.%, Portland cement (14 wt.% and a compound chemical activator containing sodium sulfate and anhydrite (6 wt.% were measured at various Blaine finenesses and curing times. Based on the obtained results, a primary stochastic model in terms of curing time and Blaine fineness has been developed. Then, another different dataset was used to incorporate composition variable including weight fractions of phosphorus slag, cement, and activator in the model. This model can be effectively used to predict the compressive strength of phosphorus slag content cements at various Blaine finenesses, curing times, and compositions.

  7. Rosebud SynCoal Partnership, SynCoal{reg_sign} demonstration technology update

    Energy Technology Data Exchange (ETDEWEB)

    Sheldon, R.W. [Rosebud SynCoal Partnership, Billings, MT (United States)

    1997-12-31

    An Advanced Coal Conversion Process (ACCP) technology being demonstrated in eastern Montana (USA) at the heart of one of the world`s largest coal deposits is providing evidence that the molecular structure of low-rank coals can be altered successfully to produce a unique product for a variety of utility and industrial applications. The product is called SynCoal{reg_sign} and the process has been developed by the Rosebud SynCoal Partnership (RSCP) through the US Department of Energy`s multi-million dollar Clean Coal Technology Program. The ACCP demonstration process uses low-pressure, superheated gases to process coal in vibrating fluidized beds. Two vibratory fluidized processing stages are used to heat and convert the coal. This is followed by a water spray quench and a vibratory fluidized stage to cool the coal. Pneumatic separators remove the solid impurities from the dried coal. There are three major steps to the SynCoal{reg_sign} process: (1) thermal treatment of the coal in an inert atmosphere, (2) inert gas cooling of the hot coal, and (3) removal of ash minerals. When operated continuously, the demonstration plant produces over 1,000 tons per day (up to 300,000 tons per year) of SynCoal{reg_sign} with a 2% moisture content, approximately 11,800b Btu/lb and less than 1.0 pound of SO{sub 2} per million Btu. This product is obtained from Rosebud Mine sub-bituminous coal which starts with 25% moisture, 8,600 Btu/lb and approximately 1.6 pounds of SO{sub 2} per million Btu.

  8. Pyrochemical recovery of plutonium fluoride reduction slag

    International Nuclear Information System (INIS)

    Christensen, D.C.; Rayburn, J.A.

    1983-07-01

    A process was developed for the pyrochemical recovery of plutonium from residues resulting from the PuF 4 reduction process. The process involves crushing the CaF 2 slag and dissolving it at 800 0 C in a CaCl 2 solvent. The plutonium, which exists either as finely divided metal or as incompletely reduced fluoride salt, is reduced to metal and/or allowed to coalesce as a massive button in the bottom of the reaction crucible. The recovery of plutonium in a 1-day cycle averaged 96%; all of the resulting residues were discardable

  9. Investigations on steel slag re-utilization in developing countries; Hatten tojokoku ni okeru tekko slag sairiyo ni kansuru chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    In order to promote steel slag re-utilization in developing countries, a possibility was presented for technical cooperation to India, Indonesia and Thailand upon putting the status of slag utilization in Japan into order. Blast furnace slag produced in Japan (having a re-utilization rate of 95%) is re-utilized and processed as cement aggregates and road beds, and converter slag as civil engineering materials and ores. Steel making slag (having a re-utilization rate of 80%) is re-utilized as road, processing and civil engineering materials. Since the steel making slag faces intensifying competition with ash made by incinerating construction and general wastes, it is important to improve its price competitiveness or mixed utilization with other materials. Re-utilization has not advanced to a recognizable level in developing countries because of having no difficulty for availability of lands for wastes. However, growth of full-scale steel industries and elevation in tendency of environment preservation now urge increase in the slag re-utilization rate. Required to achieve the goal would include wider use of re-utilization technologies, quality control on slag, joint use of facilities to produce re-utilization products, and governmental assistance on burdens of transportation cost. Assistance from Japan is expected to help meet these requirements. 25 figs., 31 tabs.

  10. International Coal Report's coal year 1991

    Energy Technology Data Exchange (ETDEWEB)

    McCloskey, G [ed.

    1991-05-31

    Following introductory articles on factors affecting trade in coal and developments in the freight market, tables are given for coal exports and coal imports for major countries worldwide for 1989 and 1990. Figures are also included for coal consumption in Canada and the Eastern bloc,, power station consumption in Japan, coal supply and demand in the UK, electric utility coal consumption and stocks in the USA, coal production in Australia, Canada and USA by state, and world hard coal production. A final section gives electricity production and hard coal deliveries in the EEC, sales of imported and local coal and world production of pig iron and steel.

  11. WABASH RIVER COAL GASIFICATION REPOWERING PROJECT

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2000-09-01

    The close of 1999 marked the completion of the Demonstration Period of the Wabash River Coal Gasification Repowering Project. This Final Report summarizes the engineering and construction phases and details the learning experiences from the first four years of commercial operation that made up the Demonstration Period under Department of Energy (DOE) Cooperative Agreement DE-FC21-92MC29310. This 262 MWe project is a joint venture of Global Energy Inc. (Global acquired Destec Energy's gasification assets from Dynegy in 1999) and PSI Energy, a part of Cinergy Corp. The Joint Venture was formed to participate in the Department of Energy's Clean Coal Technology (CCT) program and to demonstrate coal gasification repowering of an existing generating unit impacted by the Clean Air Act Amendments. The participants jointly developed, separately designed, constructed, own, and are now operating an integrated coal gasification combined-cycle power plant, using Global Energy's E-Gas{trademark} technology (E-Gas{trademark} is the name given to the former Destec technology developed by Dow, Destec, and Dynegy). The E-Gas{trademark} process is integrated with a new General Electric 7FA combustion turbine generator and a heat recovery steam generator in the repowering of a 1950's-vintage Westinghouse steam turbine generator using some pre-existing coal handling facilities, interconnections, and other auxiliaries. The gasification facility utilizes local high sulfur coals (up to 5.9% sulfur) and produces synthetic gas (syngas), sulfur and slag by-products. The Project has the distinction of being the largest single train coal gasification combined-cycle plant in the Western Hemisphere and is the cleanest coal-fired plant of any type in the world. The Project was the first of the CCT integrated gasification combined-cycle (IGCC) projects to achieve commercial operation.

  12. To the problem of nonmetallic inclusions assimilation by slags in the course of steel casting

    International Nuclear Information System (INIS)

    Klimov, Yu.V.; Krupman, L.I.; Medzhibozhskij, M.Ya.; Povkh, Yu.I.; Belanenko, A.A.

    1975-01-01

    The effect of slag viscosity as well as a method of steel pouring with slag-forming mixtures used upon the slag assimilation of oxide inclusions has been studied with a radioactive tracer method. The inclusions are absorbed by slag primarily in the course of filling casting moulds when a relatively intensive metal circulation occurs. The ensuing decrease of slag viscosity results in better purification of steel from inclusions. In the period of natural convection the inclusions are not removed irrespective of the slag properties. The bottom pouring results in the lowest degree of steel purification from inclusions due to the limited surface of a slag-metal contact

  13. Remediation of Acid Generating Colliery Spoil Using Steel Slag – Case Studies

    Directory of Open Access Journals (Sweden)

    Ghataora Gurmel S.

    2015-06-01

    Full Text Available One of the legacies of the coal mining industry is the existence of numerous colliery spoil mounds. Run-off waters from some of these mounds result in oxidation of sulphur compounds causing pH to drop to perhaps as low as 2.5. At this pH, mobility for metals increases and it results in destruction of both flora and fauna. In order to reduce acidity, a number of solutions have been investigated with varying degree of success. A recent study to reduce acidity in spoil run-off water included the use of Basic Oxygen Steel slag. Its slow release of lime resulted in longer term remediation compared with other techniques. In addition to this, steel slag contains elements which are essential for plant growth and can be regarded as a weak fertiliser. This was substantiated in two field trials, which had the aim of not only remediating acidity from two different types of colliery spoils, but also to develop a composition that supports grass growth. The objectives were achieved at both sites and some of the results of over 5000 chemical tests conducted during these studies are reported in this paper.

  14. Coal gasification plant

    Energy Technology Data Exchange (ETDEWEB)

    1977-09-29

    The proposal concerns a stage in the process of cooling the synthetic gas produced in a coal gasification plant at temperatures above 900/sup 0/C. The purpose is to keep the convection heating surface of the subsequent waste heat plant free of dirt. According to the invention, the waste heat plant has a radiation area connected before it, on the heating surfaces of which the slack carried over solidifies. This radiation area has a hydraulic and thermal cleaning system, which can be raised or lowered in a water bath. The subclaims concern all the constructional characteristics of this cleaning system, which causes the solidified slack to crack.

  15. Converting coal

    Energy Technology Data Exchange (ETDEWEB)

    Avigliano, A. [Bedeschi (Italy)

    2006-10-15

    In September 2005, Bedeschi was commissioned to design and supply a coal unloading, conveying and storage facility for a new raw coal line system within Hatien II Cement Co. The new plant is composed of a grab unloader, a conveyor system, a storage shed with stacking and reclaiming facilities, a complete dedusting system and civil and steel structure engineering. The scope of supply includes a local fabrication portion; however, main components will be imported. The project will be completed in 21 months. The paper looks into the mechanics of loading and unloading coal. 4 figs., 4 photos.

  16. Utilizing steel slag in environmental application - An overview

    Science.gov (United States)

    Lim, J. W.; Chew, L. H.; Choong, T. S. Y.; Tezara, C.; Yazdi, M. H.

    2016-06-01

    Steel slags are generated as waste material or byproduct every day from steel making industries.The potential environmental issues which are related with the slag dump or reprocessing for metal recovery are generally being focused in the research. However the chemistry and mineralogy of slag depends on metallurgical process which is able to determine whether the steel slag can be the reusable products or not. Nowadays, steel slag are well characterized by using several methods, such as X-ray Diffraction, ICP-OES, leaching test and many more. About the industrial application, it is mainly reused as aggregate for road construction, as armour stones for hydraulic engineering constructions and as fertilizers for agricultural purposes. To ensure the quality of steel slag for the end usage, several test methods are developed for evaluating the technical properties of steel slag, especially volume stability and environmental behaviour. In order to determine its environmental behaviour, leaching tests have been developed. The focus of this paper however is on those applications that directly affect environmental issues including remediation, and mitigation of activities that negatively impact the environment.

  17. Calibration-free electrical conductivity measurements for highly conductive slags

    International Nuclear Information System (INIS)

    Macdonald, Christopher J.; Gao, Huang; Pal, Uday B.; Van den Avyle, James A.; Melgaard, David K.

    2000-01-01

    This research involves the measurement of the electrical conductivity (K) for the ESR (electroslag remelting) slag (60 wt.% CaF 2 - 20 wt.% CaO - 20 wt.% Al 2 O 3 ) used in the decontamination of radioactive stainless steel. The electrical conductivity is measured with an improved high-accuracy-height-differential technique that requires no calibration. This method consists of making continuous AC impedance measurements over several successive depth increments of the coaxial cylindrical electrodes in the ESR slag. The electrical conductivity is then calculated from the slope of the plot of inverse impedance versus the depth of the electrodes in the slag. The improvements on the existing technique include an increased electrochemical cell geometry and the capability of measuring high precision depth increments and the associated impedances. These improvements allow this technique to be used for measuring the electrical conductivity of highly conductive slags such as the ESR slag. The volatilization rate and the volatile species of the ESR slag measured through thermogravimetric (TG) and mass spectroscopy analysis, respectively, reveal that the ESR slag composition essentially remains the same throughout the electrical conductivity experiments

  18. Characterization and recovery of copper values from discarded slag.

    Science.gov (United States)

    Das, Bisweswar; Mishra, Barada Kanta; Angadi, Shivakumar; Pradhan, Siddharth Kumar; Prakash, Sandur; Mohanty, Jayakrushna

    2010-06-01

    In any copper smelter large quantities of copper slag are discarded as waste material causing space and environmental problems. This discarded slag contains important amounts of metallic values such as copper and iron. The recovery of copper values from an Indian smelter slag that contains 1.53% Cu, 39.8% Fe and 34.65% SiO(2) was the focus of the present study. A complete investigation of the different phases present in the slag has been carried out by means of optical microscopy, Raman spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD) techniques. It is observed that iron and silica are mostly associated with the fayalite phase whereas copper is present in both oxide and sulfide phases. These oxide and sulfide phases of copper are mostly present within the slag phase and to some extent the slag is also embedded inside the oxide and sulfide phases. The recovery of copper values from the discarded slag has been explored by applying a flotation technique using conventional sodium isopropyl xanthate (SIX) as the collector. The effects of flotation parameters such as pH and collector concentration are investigated. Under optimum flotation conditions, it is possible to achieve 21% Cu with more than 80% recovery.

  19. Alkali-slag cements for the immobilization of radioactive wastes

    International Nuclear Information System (INIS)

    Shi, C.; Day, R.L.

    1996-01-01

    Alkali-slag cements consist of glassy slag and an alkaline activator and can show both higher early and later strengths than Type III Portland cement, if a proper alkaline activator is used. An examination of microstructure of hardened alkali-slag cement pastes with the help of XRD and SEM with EDAX shows that the main hydration product is C-S-H (B) with low C/S ratio and no crystalline substances exist such as Ca(OH) 2 , Al (OH) 3 and sulphoaluminates. Mercury intrusion tests indicate that hardened alkali-slag cement pastes have a lower porosity than ordinary Portland cement, and contain mainly gel pores. The fine pore structure of hardened alkali-slag cement pastes will restrict the ingress of deleterious substances and the leaching of harmful species such as radionuclides. The leachability of Cs + from hardened alkali-slag cement pastes is only half of that from hardened Portland cement. From all these aspects, it is concluded that alkali-slag cements are a better solidification matrix than Portland cement for radioactive wastes

  20. Vanadium bioavailability in soils amended with blast furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, Maja A., E-mail: maja.larsson@slu.se [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, 750 07 Uppsala (Sweden); Baken, Stijn, E-mail: stijn.baken@ees.kuleuven.be [Department of Earth and Environmental Sciences, Leuven University, Kasteelpark Arenberg 20 bus 2459, 3001 Leuven (Belgium); Smolders, Erik, E-mail: erik.smolders@ees.kuleuven.be [Department of Earth and Environmental Sciences, Leuven University, Kasteelpark Arenberg 20 bus 2459, 3001 Leuven (Belgium); Cubadda, Francesco, E-mail: francesco.cubadda@iss.it [Department of Food Safety and Veterinary Public Health, Istituto Superiore di Sanità, Viale Regina Elena 299, Rome 00161 (Italy); Gustafsson, Jon Petter, E-mail: jon-petter.gustafsson@slu.se [Department of Soil and Environment, Swedish University of Agricultural Sciences, P.O. Box 7014, 750 07 Uppsala (Sweden); Division of Land and Water Resources Engineering, KTH Royal Institute of Technology, Brinellvägen 28, 100 44 Stockholm (Sweden)

    2015-10-15

    Blast furnace (BF) slags are commonly applied as soil amendments and in road fill material. In Sweden they are also naturally high in vanadium. The aim of this study was to assess the vanadium bioavailability in BF slags when applied to soil. Two soils were amended with up to 29% BF slag (containing 800 mg V kg{sup −1}) and equilibrated outdoors for 10 months before conducting a barley shoot growth assay. Additional soil samples were spiked with dissolved vanadate(V) for which assays were conducted two weeks (freshly spiked) and 10 months (aged) after spiking. The BF slag vanadium was dominated by vanadium(III) as shown by V K-edge XANES spectroscopy. In contrast, results obtained by HPLC-ICP-MS showed that vanadium(V), the most toxic vanadium species, was predominant in the soil solution. Barley shoot growth was not affected by the BF slag additions. This was likely due to limited dissolution of vanadium from the BF slag, preventing an increase of dissolved vanadium above toxic thresholds. The difference in vanadium bioavailability among treatments was explained by the vanadium concentration in the soil solution. It was concluded that the vanadium in BF slag is sparingly available. These findings should be of importance in environmental risk assessment.

  1. The Effect Of Local Coal And Smelting Sponge Iron On Iron Content Of Pig Iron

    Science.gov (United States)

    Oediyani, Soesaptri; Juwita Sari, Pramita; Hadi P, Djoko

    2018-03-01

    The new regulation on mineral resources was announced by Ministry of Energy and Mineral resources (ESDM) of Indonesia at 2014 which it called Permen ESDM No 1/2014. Therefore, this research was conducted to add the value of local iron ores by using smelting technology. The objective of the research is to produce pig iron that meet the requirement of the new regulation of mineral resources such as 90% Fe. First, iron ores and coal mixed together with lime as a flux, then smelted in a Electric Arc Furnace at 1800°C. The process variables are (1; 1.25; 1.5; 1.75; 2.0) and the composition of coal (0.8%, 1.6%, 3.0%). The type of coal that used in this research was bituminous coal from Kalimantan and also the iron ores from Kalimantan. The products of the smelting technology are Pig iron and slag. Both pig iron and slag then analyzed by SEM-EDS to measure the iron content. The result shows that the maximum iron content on pig iron is about 95.04% meanwhile the minimum iron content on slag is about 3.66%. This result achieved at 1.6% coal and 2.0.

  2. Thermodynamic modelling of alkali-activated slag cements

    International Nuclear Information System (INIS)

    Myers, Rupert J.; Lothenbach, Barbara; Bernal, Susan A.; Provis, John L.

    2015-01-01

    Highlights: • A thermodynamic modelling analysis of alkali-activated slag cements is presented. • Thermodynamic database describes zeolites, alkali carbonates, C–(N–)A–S–H gel. • Updated thermodynamic model for Mg–Al layered double hydroxides. • Description of phase assemblages in Na 2 SiO 3 - and Na 2 CO 3 -activated slag cements. • Phase diagrams for NaOH-activated and Na 2 SiO 3 -activated slag cements are simulated. - Abstract: This paper presents a thermodynamic modelling analysis of alkali-activated slag-based cements, which are high performance and potentially low-CO 2 binders relative to Portland cement. The thermodynamic database used here contains a calcium (alkali) aluminosilicate hydrate ideal solid solution model (CNASH-ss), alkali carbonate and zeolite phases, and an ideal solid solution model for a hydrotalcite-like Mg–Al layered double hydroxide phase. Simulated phase diagrams for NaOH- and Na 2 SiO 3 -activated slag-based cements demonstrate the high stability of zeolites and other solid phases in these materials. Thermodynamic modelling provides a good description of the chemical compositions and types of phases formed in Na 2 SiO 3 -activated slag cements over the most relevant bulk chemical composition range for these cements, and the simulated volumetric properties of the cement paste are consistent with previously measured and estimated values. Experimentally determined and simulated solid phase assemblages for Na 2 CO 3 -activated slag cements were also found to be in good agreement. These results can be used to design the chemistry of alkali-activated slag-based cements, to further promote the uptake of this technology and valorisation of metallurgical slags

  3. Minimizing lead release levels in secondary smelters slags

    International Nuclear Information System (INIS)

    Shenkler, E.S.; Graham, S.; Ghosh, R.; Greenhut, V.A.

    1991-01-01

    Five lead-containing slags and four mattes were analyzed to reveal microstructure, semi-quantitative microchemistry, and phases present. To determine if the slags could be incorporated as a glass so that lead release levels could be stabilized, glass batches were formulated based on slag compositions. Leaching tests showed that all materials that were fritted in a glass batch had lower lead release levels than non-adjusted materials, and all could satisfy EPA test requirements. The mole ratio of glass modifiers to glass formers played an important role in the extent of lead release. Small additions of phosphate to a batch had a significant effect on lowering lead release levels

  4. Moessbauer study of ancient iron smelting slag in Japan

    International Nuclear Information System (INIS)

    Nakanishi, A.

    2008-01-01

    For an investigation of the ancient iron manufacturing technique, a reproducing experiment was carried out by archaeologists, where ancient type of iron smelting furnace was built and iron sand with high titanium contents was used as the raw material. During the operation of furnace, a large amount of slag flowed away from the furnace. In order to investigate the possibility for the estimation about the operative condition of furnace and the raw material, 57 Fe Moessbauer spectroscopy was applied for characterizing these slags and it was found that these slags mainly consisted of ferropseudobrookite (FeTi 2 O 5 ).

  5. Numerical Investigations on the Slag Eye in Steel Ladles

    Directory of Open Access Journals (Sweden)

    Yan-He Liu

    2014-04-01

    Full Text Available A numerical model has been developed to analyze the transient three-dimensional and three-phase flow in a bottom stirring ladle with a centered porous plug, which takes into account the steel, gas, and slag phases; it enables us to predict the fluid flow and heat transfer in the very important steel/slag region. The numerical results of the present model show that the obtained relationship between nondimensional areas of slag eye and the Froude number is in good agreement with the reported data.

  6. Optimizing of Work Arc Furnace to Decopperisation of Flash Slag

    Directory of Open Access Journals (Sweden)

    Bydałek A.W.

    2015-09-01

    Full Text Available Discusses an attempt to optimize the operation of an electric furnace slag to be decopperisation suspension of the internal recycling process for the production of copper. The paper presents a new method to recover copper from metallurgical slags in arc-resistance electric furnace. It involves the use of alternating current for a first period reduction, constant or pulsed DC in the final stage of processing. Even distribution of the electric field density in the final phase of melting caused to achieve an extremely low content of metallic copper in the slag phase. They achieved by including the economic effects by reducing the time reduction.

  7. Coal competitiveness?

    International Nuclear Information System (INIS)

    Rogeaux, B.

    2006-01-01

    Will coal electrical plants be more competitive in the coming years? Answering this one cannot be limited to merely comparing estimates based on reference electricity production costs. The competitiveness of coal will indeed depend on the final product marketed, as the MWhs are not equal: is the purpose to produce base, half-base MWh? Does the electrical equipment structure require flexible MWh (for instance in the event of significant intermittent renewable energy amounts), and therefore plants able to adjust their power rapidly? But the competitiveness of coal will also depend on many factors that will correct reference cost estimates: uncertainties, risks, externalities. These factors will need to be appreciated on a case by case basis. We introduce some of the reasoning used to better appreciate the future competitiveness of coal, and the main factors conditioning it in three contrasting regions of the world: Europe, USA, china. (author)

  8. Corrosion of ceramics for slag removal in IGCC-power plants; Korrosion von Keramiken fuer die Fluessigascheabscheidung in IGCC-Kraftwerken

    Energy Technology Data Exchange (ETDEWEB)

    Fuerst, Denny

    2012-06-12

    Coal gasification and the subsequent production of electricity from syngas in combined-cycle powerplants allows plant efficiencies of up to 43% (LHV). Existing technologies allow up to 50% in the short term. Efficiencies beyond 50% however, require concepts and technologies that still need a certain amount of research and development. One such method to raise plant efficiencies would be a high temperature (at temperatures above the melting point of the ash) syngas cleaning. To effectively utilize the heat from the syngas and enable high turbine inlet temperatures, it is necessary to remove slag particles from the hot gas. The feasibility of such a hot syngas cleaning has been successfully demonstrated for the Pressurized Pulverized Coal Combustion (PPCC) by passing the hot gas through a bed of ceramic balls for slag removal. In order to apply this concept to IGCC powerplants the slag resistance of various ceramic materials had to be investigated under gasifying conditions. Therefore, lab-made ceramics and commercially available refractory materials where treated with liquid slag at 1600 C in a number of reducing atmospheres. At first, three synthetic slags with different basicity were used and after evaluating the results, selected materials were treated with a gasifier slag under continuous conditions. It was shown that both slag and ceramic have to be adjusted to ensure a sufficient corrosion resistance of the ceramic bed for slag removal. Furthermore, the impact of the porosity of the utilized ceramic on the corrosion resistance was shown. The composition of the reducing atmosphere (mainly the partial pressure of Oxygen) affected both physical and chemical properties of the slag via slag components that could easily be reduced or oxidized. The materials most suitable for use in slag separation were found to be dense chromium oxide and other ceramics containing a high amount of chromium oxide. [German] Mit Kohlevergasung und der anschliessenden Stromerzeugung in

  9. Coal - 97

    International Nuclear Information System (INIS)

    Sparre, C.

    1997-01-01

    The report deals with the use of coal and coke during 1996. Some information about techniques, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from SCB have also been used. The use of steam coal for heating purposes during 1996 was 1,2 mill tons and 50% higher than in 1995. The increase is probably temporary and due to high prices of electricity because of lack of water power. The co-generation plants were the main users of coal. The minor plants have increased their use of forest fuels. Probably the use of steam coal will go down in the immediate years both in the heat generating and the co-generation plants. During the top year 1987 coal was used in 18 hotwater plants and 11 co-generation plants. 1996 these figures are 3 and 12. Taxes and environmental reasons explain this trend. The use of steam coal in the industry has been constant at the level 700 000 tons. This level is supposed to be constant or to vary with business cycles. The import of metallurgical coal in 1996 was 1,6 mill tons like the year before. 1,2 mill tons coke were produced. The coke consumption in the industry was 1,5 mill tons. 0,3 mill tons of coke were imported. The average price of steam coal imported in Sweden in 1996 was 340 SEK/ton or 2% higher than in 1995. For the world, the average import price was 51,5 USD/ton, nearly the same as the year before. The contract prices for delivery during 1997 are about equal as the end of 1996. All Swedish plants meet their emission limits of dust, SO 2 and NO x given by county administrations or concession boards

  10. Production of precipitated calcium carbonate from industrial byproduct slags; Saostetun kalsiumkarbonaatin tuotanto karbonaattivapaista kuonatuotteista (SLAG2PCC)

    Energy Technology Data Exchange (ETDEWEB)

    Zevenhoven, R. [Aabo Akademi, Turku (Finland). Heat Engineering Lab.; Teir, S.; Eloneva, S.; Savolahti, J. [Helsinki Univ. of Technology, Espoo (Finland). Energy Technology and Environmental Protection

    2006-12-19

    Production of precipitate calcium carbonate from industrial by- product slags-project, 'SLAG2PCC', is a spin-off from ClimBus technology programme CO{sub 2} Nordic Plus-project, financed by the Finnish Technology Agency Tekes and the Finnish Recovery Boiler Committee. 'SLAG2PCC'-project is financed by Tekes, Ruukki Productions, UPM Kymmene and Waertsilae Finland. The possibility to produce precipitated calcium carbonate, PCC, from carbonate free industrial by-products (slags), combined with binding of carbon dioxide for climate change mitigation is studied in this project. The suitability of a process found from the literature, in which calcium used for carbonation is dissolved from calcium silicates using acetic acid as a solvent, is investigated for the carbonation of slags from the steel industry. During the calcium extraction experiments performed in the CO2 Nordic Plus - project it was found out that calcium is rapidly extracted from blast furnace and basic oxygen furnace slags. Atmospheric carbonation of the solution containing the dissolved slag and acetic acid directly has not succeeded yet due to low pH of the solution. Addition of NaOH, to increase of the solution pH, resulted in calcium carbonate precipitate in atmospheric pressure. The future goal of the project is to optimize process conditions so that the formed calcium carbonate is suitable for use as PCC. (orig.)

  11. Radioactivity levels in Indian coal and some technologically enhanced exposure to natural radiation environment of India

    International Nuclear Information System (INIS)

    Ramachandran, T.V.; Mishra, U.C.

    1988-01-01

    The summary of results of gamma-spectrometric measurements of natural radioactivity levels in coal from mines, coal, fly-ash, slag and soil samples from thermal power plants in India are presented. These constitute the sources of technologic ally enhanced exposures to natural radiation. Brief description of sampling and measurement procedure is given. Radiation dose to the population from coal fired power plants for electricity generation have been calculated using the model developed by UNSCEAR and ORNL reports with correction for local population density. (author). 13 refs., 7 tabs., 8 figs

  12. Good news to use from the environmental front: coal combustion products as an environmental success story

    Energy Technology Data Exchange (ETDEWEB)

    Ward, J.N. [ISG Resources, Inc., Salt Lake City, UT (United States)

    2002-07-01

    ISG Resources in the USA's largest manager and marketer of coal combustion products, involved also in developing new technologies and applications for treatment and use of fly ash, bottom ash, boiler slag and FGD by-products. The paper, outlined in a series of 14 overheads, describes the USA's successes and initiatives so far in coal combustion products utilization. Further opportunities for the coal industry were discussed. The industry is encouraged to become involved now in carbon trading mechanisms for fly ash utilization displacing cement production.

  13. Strength and corrosion behavior of SiC - based ceramics in hot coal combustion environments

    Energy Technology Data Exchange (ETDEWEB)

    Breder, K.; Parten, R.J. [Oak Ridge National Lab., TN (United States)

    1996-08-01

    As part of an effort to evaluate the use of advanced ceramics in a new generation of coal-fired power plants, four SiC-based ceramics have been exposed to corrosive coal slag in a laboratory furnace and two pilot scale combustors. Initial results indicate that the laboratory experiments are valuable additions to more expensive pilot plant experiments. The results show increased corrosive attack with increased temperature, and that only slight changes in temperature may significantly alter the degree of strength degradation due to corrosive attack. The present results are part of a larger experimental matrix evaluating the behavior of ceramics in the coal combustion environment.

  14. SELECTION OF SUSTAINABLE TECHNOLOGIES FOR COMBUSTION OF BOSNIAN COALS

    Directory of Open Access Journals (Sweden)

    Anes Kazagić

    2010-01-01

    Full Text Available This paper deals with optimization of coal combustion conditions to support selection a sustainable combustion technology and an optimal furnace and boiler design. A methodology for optimization of coal combustion conditions is proposed and demonstrated on the example of Bosnian coals. The properties of Bosnian coals vary widely from one coal basin to the next, even between coal mines within the same basin. Very high percentage of ash (particularly in Bosnian brown coal makes clear certain differences between Bosnian coal types and other world coal types, providing a strong argument for investigating specific problems related to the combustion of Bosnian coals, as well as ways to improve their combustion behaviour. In this work, options of the referent energy system (boiler with different process temperatures, corresponding to the different combustion technologies; pulverised fuel combustion (slag tap or dry bottom furnace and fluidized bed combustion, are under consideration for the coals tested. Sustainability assessment, based on calculation economic and environment indicators, in combination with common low cost planning method, is used for the optimization. The total costs in the lifetime are presented by General index of total costs, calculated on the base of agglomeration of basic economic indicators and the economic indicators derived from environmental indicators. So, proposed methodology is based on identification of those combustion technologies and combustion conditions for coals tested for which the total costs in lifetime of the system under consideration are lowest, provided that all environmental issues of the energy system is fulfilled during the lifetime. Inputs for calculation of the sustainability indicators are provided by the measurements on an experimental furnace with possibility of infinite variation of process temperature, supported by good praxis from the power plants which use the fuels tested and by thermal

  15. Power Generation from Coal 2010

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Coal is the biggest single source of energy for electricity production and its share is growing. The efficiency of converting coal into electricity matters: more efficient power plants use less fuel and emit less climate-damaging carbon dioxide. This book explores how efficiency is measured and reported at coal-fired power plants. With many different methods used to express efficiency performance, it is often difficult to compare plants, even before accounting for any fixed constraints such as coal quality and cooling-water temperature. Practical guidelines are presented that allow the efficiency and emissions of any plant to be reported on a common basis and compared against best practice. A global database of plant performance is proposed that would allow under-performing plants to be identified for improvement. Armed with this information, policy makers would be in a better position to monitor and, if necessary, regulate how coal is used for power generation. The tools and techniques described will be of value to anyone with an interest in the more sustainable use of coal.

  16. Coal -98

    International Nuclear Information System (INIS)

    Sparre, C.

    1998-01-01

    The following report deals with the use of coal and coke during 1997. Some information about technic, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from SCB have also been used. The use of steam coal for heating purposes during 1997 was 730 000 tons and about 500 000 tons lower than in 1996. The extremely high figures of 1996 were due to twice the production of electricity because of lack of hydro power. The co-generation plants were the main users of coal. The minor plants have increased their use of forest fuels. Probably the use of steam coal will go down in the immediate years both in the heat generating and the co-generating plants. Some foreign analysts, however, estimate a doubled use of coal for energy use after 2020 because of the plans to phase out the nuclear power. During the top year 1987 coal was used in 18 hot water plants and 11 co-generation plants. 1997 these figures are 2 and 8. Taxes and environmental reasons explain this trend. The use of steam coal in the industry has been constant at the level 700 000 tons. This level is supposed to be constant or to vary with business cycles. The import of metallurgical coal in 1997 was 1.6 mill tons like the year before. 1.2 mill tons coke were produced. The coke consumption in the industry was 1.5 Mill tons. 0.3 mill tons of coke were imported. Several other plants have plans to replace the coal with forest fuels, waste fuels and NG. Even the biggest plant, Vaesteraas, has plans to build a block for bio fuels. Helsingborg has started to use wood pellets. The pellets replace most of the coal for the heat production in the co-generation plant. Norrkoeping Kraft AB has taken a fluid bed boiler for different fuels in operation, leading to more than half the coal consumption compared with previous years. They have also rebuilt one of their travelling grates for bio fuels. Stockholm

  17. Effect of mineral oxides on slag formation tendency of Mae Moh lignites

    Directory of Open Access Journals (Sweden)

    Anuwat Luxsanayotin

    2010-08-01

    Full Text Available Slagging is one of major ash deposition problems experienced in the boilers of coal–fired power plants especially theplants that use lignite, like Mae Moh lignites. The occurrence of slag is a complex phenomenon depending on several factorssuch as ash properties, furnace operating conditions, and coal properties. The main objective of this work is to study theeffect of mineral components in Mae Moh lignite on ash fusion temperatures (AFTs, which is commonly used as a keyindicator for slag formation tendency under pulverized combustion conditions. Two Mae Moh lignites from the coal seamsplanned to be used in the future were selected for the study to represent low CaO and high CaO lignite. The two lignites,namely K1 and K3, have 3.6 and 40.4 wt% CaO in ash, respectively. The AFT characterization shows that their initial deformationtemperatures (ITs were almost identical and considered as low for the typical flue gas temperature in the radiationsection of Mae Moh boilers, i.e. 1050-1100°C. These observed similar ITs were rather unexpected, especially for K1 consideringits sufficiently low base to acid (B/A ratios. The X-ray diffraction analyses evidently show the presence of illite, pyriteand anhydrite in K1, which explains the observed lower IT of the sample. Anhydrite, which is known to lower the ITs, is alsothe most abundant mineral in K3. Washing the lignite samples with HCl can significantly reduce CaO, MgO, and SO3 contentin the ash but not Fe2O3 as it is present in the form of pyrite. The addition of Al2O3, SiO2 and Fe2O3 can help increase AFTs ofthe studied samples. The Al2O3 addition gives the strongest effect on increasing AFTs, especially for the sample with lowAl2O3 content. When the CaO is added to the low CaO samples, the fluxing effect will initially occur. However, when the CaOcontent is higher than a critical value (i.e. CaO > 38%, the effect of its high melting point will dominate hence the AFTsincreased. Ternary phase diagrams

  18. Cooling towers

    International Nuclear Information System (INIS)

    Boernke, F.

    1975-01-01

    The need for the use of cooling systems in power plant engineering is dealt with from the point of view of a non-polluting form of energy production. The various cooling system concepts up to the modern natural-draught cooling towers are illustrated by examples. (TK/AK) [de

  19. Coal log pipeline research at the University of Missouri. 1st Quarterly report for 1995, January 1, 1995--March 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H.

    1995-08-01

    Work continued on the study of coal log pipeline research. Individual projects described include fast compaction of coal logs; effect of cooling on coal log quality; coal log capping; effectiveness of adding fiber to enhance coal log quality; fabrication using hydrophobic binders; cost estimation of different lubricants; automatic control of coal log pipeline system; CLP design; coal log train transport; economics of coal log pipeline; legal aspects; heating, cooling, and drying of logs; vacuum systems to enhance production; design; and effect of piston modification on capping.

  20. Characterization of ancient Indian iron and entrapped slag ...

    Indian Academy of Sciences (India)

    year old Indian iron using microprobe techniques (EDS, XRD and PIXE). Several different local locations in the iron matrix and in the entrapped slag inclusions were analyzed. The P content of the metallic iron matrix was very heterogeneous.

  1. Evaluation of Grade 120 Granulated Ground blast Furnace Slag.

    Science.gov (United States)

    1999-06-01

    This study evaluates Grade 120 Granulated Ground Blast Furnace Slag (GGBFS) and its effect on the properties of hydraulic cement concretes used in structural and pavement construction. Several mix designs, structural and pavement, were used for this ...

  2. Brief summary of slag handling options reviewed for the slagging pyrolysis incinerator in the transuranic waste treatment facility (TWIF) at the INEL

    International Nuclear Information System (INIS)

    Darnell, G.R.

    1980-06-01

    This report summarizes the technical problems associated with molten transuranic waste slag as it flows from the incinerator shaft (gasifier) of the slagging pyrolysis incinerator. It addresses essential gasifier seals, slag casting and pouring technology, and transportation and packaging problems. Areas requiring further study and testing are identified

  3. Coal 95

    International Nuclear Information System (INIS)

    Sparre, C.

    1995-01-01

    The report deals with the use of coal and coke in Sweden during 1994. Some information about technology, environmental questions and markets are also given. Data have been collected by questionnaires to major users and by telephone to minor users. Preliminary statistical data from Statistics Sweden have also been used.The use of steam coal for heating purposes has been unchanged during 1994 at a level of 1 Mtons. The production in the cogeneration plants has been constant, but has increased for electricity production. The minor plants have increased their use of forest fuels. The use of steam coal will probably go down in the next years both for heat and cogeneration plants. During the top year 1987 coal was used in 18 hot water and 11 cogeneration plants. 1994 these figures are 3 and 12. Taxes and environmental reasons explain this trend. The use of steam coal in industry has been constant at the level 0.7 Mtons. The import of metallurgical coal in 1993 was 1.6 Mtons, like 1992. Import of 0.3 Mtons of coke gives the total consumption of coke in industry as 1.5 Mtons. the average price of steam coal imported to Sweden was 317 SEK/ton, 3% higher than 1993. All Swedish plants meet their emission limit of dust, SO 2 and NO x as given by county administrations or concession boards. The cogeneration plants all have some SO 2 removal system. The biggest cogeneration plant (Vaesteraas) has recently invested in a SCR NO x cleaning system. Most other plants use low NO x burners or SNR injection systems based on ammonia or urea. 2 figs, 13 tabs

  4. Evaluation study on rationalization of coal handling in snowy area

    Energy Technology Data Exchange (ETDEWEB)

    Suesada, Yasuhiko; Yamagata, Keisuke; Kuwahara, Mitsuhiro

    1987-09-25

    The adhesion of coal to the coal handling facilities in large cool-fired power plants in the snowy area was investigated for siting them in the future. The amount of water derived from melted snow in addition to that from the rain fall were measured and the statistical amounts of rain and snow falls for the past ten years were examined. Then the amount of water derived from melted snow was calculated by regression. The result indicates that the amount of rain fall in summer is larger than that from melted snow. The moisture content of coal in a coal yard reaches the moisture content at which the coal readily adheres to the facilities after snow fall and it penetrates the pile of coal to the bottom with the lapse of time. The penetrating rate of it largely depends upon the particle distribution of coal as well as the ranks of coal. The adhesion of coal to the coal handling facilities is caused mainly by the amount of dust coal and the moisture content of coal. The amount of adhered coal estimated from the shear properties qualitatively agrees with the experimental result using a model of chute. Adding the dusting inhibitor exceeding the normal value increases the amount of of adhesion of coal. (13 figs, 3 tabs)

  5. THERMAL AND SINTERING CHARACTERIZATION OF A IGCC SLAG

    OpenAIRE

    Acosta, Anselmo; Iglesias, Isabel; Aineto, Mónica; Romero, Maximina; Rincón López, Jesús María

    2002-01-01

    IGCC slag is a vitreous residual product from the new induction gasification combined cycle gasification thermal power plants. In order to characterize this waste as secondary new material for the production of new glasses and glass-ceramics as construction materials; this slag from the Puertollano, Ciudad Real, Spain power plants has been fully thermally investigated. After controlled heating this waste gives rise to hematite, anorthite, and cristobalite crystallized materials.

  6. Slag Evaluation to Reduce Energy Consumption and EAF Electrical Instability

    OpenAIRE

    Vieira,Deisi; Almeida,Rodolfo Arnaldo Montecinos de; Bielefeldt,Wagner Viana; Vilela,Antônio Cezar Faria

    2016-01-01

    In steel mills that operate with electric arc furnaces (EAF), it is interesting to ensure greater stability to the electric arc to aim at less distortion in the electrical system, with consequent reduction in electric power consumption. The slag foaming increases electric arc stability by reducing the total harmonic distortion (THD) between EAF phases. In this study, information about the chemical composition of the slag and electrical parameters of an EAF were collected. With the composition...

  7. Reuse of steel slag in bituminous paving mixtures.

    Science.gov (United States)

    Sorlini, Sabrina; Sanzeni, Alex; Rondi, Luca

    2012-03-30

    This paper presents a comprehensive study to evaluate the mechanical properties and environmental suitability of electric arc furnace (EAF) steel slag in bituminous paving mixtures. A variety of tests were executed on samples of EAF slag to characterize the physical, geometrical, mechanical and chemical properties as required by UNI EN specifications, focusing additionally on the volumetric expansion associated with hydration of free CaO and MgO. Five bituminous mixtures of aggregates for flexible road pavement were designed containing up to 40% of EAF slag and were tested to determine Marshall stability and indirect tensile strength. The leaching behaviour of slag samples and bituminous mixtures was evaluated according to the UNI EN leaching test. The tested slag showed satisfactory physical and mechanical properties and a release of pollutants generally below the limits set by the Italian code. Tests on volume stability of fresh materials confirmed that a period of 2-3 months is necessary to reduce effects of oxides hydration. The results of tests performed on bituminous mixtures with EAF slag were comparable with the performance of mixtures containing natural aggregates and the leaching tests provided satisfactory results. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Stabilization of Black Cotton Soil Using Micro-fine Slag

    Science.gov (United States)

    Shukla, Rajesh Prasad; Parihar, Niraj Singh

    2016-09-01

    This work presents the results of laboratory tests conducted on black cotton soil mixed with micro-fine slag. Different proportions of micro-fine slag, i.e., 3, 6, 9, 12 and 15 % were mixed with the black cotton soil to improve soil characteristics. The improvement in the characteristics of stabilized soil was assessed by evaluating the changes in the physical and strength parameters of the soil, namely, the Atterberg limits, free swell, the California Bearing Ratio (CBR), compaction parameters and Unconfined Compressive Strength (UCS). The mixing of micro-fine slag decreases the liquid limit, plasticity index and Optimum Moisture Contents (OMC) of the soil. Micro-fine slag significantly increases the plastic limit, UCS and CBR of the soil up to 6-7 % mixing, but mixing of more slag led to decrease in the UCS and CBR of the soil. The unsoaked CBR increased by a substantial amount unlike soaked CBR value. The swell potential of the soil is reduced from medium to very low. The optimum amount of micro-fine slag is found to be approximately 6-7 % by the weight of the soil.

  9. Properties and hydration of blended cements with steelmaking slag

    International Nuclear Information System (INIS)

    Kourounis, S.; Tsivilis, S.; Tsakiridis, P.E.; Papadimitriou, G.D.; Tsibouki, Z.

    2007-01-01

    The present research study investigates the properties and hydration of blended cements with steelmaking slag, a by-product of the conversion process of iron to steel. For this purpose, a reference sample and three cements containing up to 45% w/w steel slag were tested. The steel slag fraction used was the '0-5 mm', due to its high content in calcium silicate phases. Initial and final setting time, standard consistency, flow of normal mortar, autoclave expansion and compressive strength at 2, 7, 28 and 90 days were measured. The hydrated products were identified by X-ray diffraction while the non-evaporable water was determined by TGA. The microstructure of the hardened cement pastes and their morphological characteristics were examined by scanning electron microscopy. It is concluded that slag can be used in the production of composite cements of the strength classes 42.5 and 32.5 of EN 197-1. In addition, the slag cements present satisfactory physical properties. The steel slag slows down the hydration of the blended cements, due to the morphology of contained C 2 S and its low content in calcium silicates

  10. Applicability of Carbonated Electric Arc Furnace Slag to Mortar

    International Nuclear Information System (INIS)

    Yokoyama, S; Izaki, M; Arisawa, R; Hisyamudin, M N N; Murakami, K; Maegawa, A

    2012-01-01

    Authors have been studying the absorption of CO 2 in the steelmaking slag. In this study, an application of the electric arc furnace slag after the carbonation to admixture of mortar was investigated with the JIS (A6206-1997) method for ground granulated blast-furnace slag for concrete. The percent flows for the test mortar were smaller than that for the standard mortar. The percent flow of the carbonated slag whose average particle size of more than approximately 4 μm increased with an increase in the average size of the particles. Because the compressive strengths of the test mortar cured for 91 days were almost the same as those cured 28 days, the slag after the carbonation was thought not to have self-hardening property for a medium and long term. The compressive strength for the test mortar was almost unchanged within a range of approximately 2 to 7 μm of the average particle size, and it in this range was highest. The activity indexes for the test mortar prepared with the slag after the carbonation ranged from approximately 40 to 60%.

  11. Influence of slag-seed interaction on MHD generator performance

    International Nuclear Information System (INIS)

    Luongo, C.A.; Kruger, C.M.

    1984-01-01

    An overview of past work in the field of slag/seed interaction is presented. The ideal solution model for the slag and its failure to lead to accurate predictions are discussed. The non-ideal solution model is introduced. Data on potassium vapor pressure over slags taken at the National Bureau of Standards and Montana State University were compiled and compared. Large disagreement between these sources was observed. The shortcomings of the complete thermodynamic equilibrium models led to over predictions in the fraction of seed lost to the slag. A model including non-equilibrium effects is introduced. The heat/mass transfer analogy is invoked to calculate the mass transfer rate of potassium towards the slag. Using typical conditions for a large MHD generator, an integral method is used to evaluate the potassium concentration boundary layer thickness. The calculations are performed with the slag runoff (ash rejection) as a parameter. The increase in boundary layer resistance due to potassium depletion is calculated

  12. Long term mechanical properties of alkali activated slag

    Science.gov (United States)

    Zhu, J.; Zheng, W. Z.; Xu, Z. Z.; Leng, Y. F.; Qin, C. Z.

    2018-01-01

    This article reports a study on the microstructural and long-term mechanical properties of the alkali activated slag up to 180 days, and cement paste is studied as the comparison. The mechanical properties including compressive strength, flexural strength, axis tensile strength and splitting tensile strength are analyzed. The results showed that the alkali activated slag had higher compressive and tensile strength, Slag is activated by potassium silicate (K2SiO3) and sodium hydroxide (NaOH) solutions for attaining silicate modulus of 1 using 12 potassium silicate and 5.35% sodium hydroxide. The volume dosage of water is 35% and 42%. The results indicate that alkali activated slag is a kind of rapid hardening and early strength cementitious material with excellent long-term mechanical properties. Single row of holes block compressive strength, single-hole block compressive strength and standard solid brick compressive strength basically meet engineering requirements. The microstructures of alkali activated slag are studied by X-ray diffraction (XRD). The hydration products of alkali-activated slag are assured as hydrated calcium silicate and hydrated calcium aluminate.

  13. Coal preparation

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The acid rain control legislation has prompted the Department of Energy (DOE) to seek new technology using the Clean Coal Technology program solicitation. The main goal of the program is to reduce SO 2 emissions below 9 Mt/a (10 million stpy) and NO x emission below 5.4 Mt/a (6 million stpy) by the year 2000. This would be accomplished by using precombustion, combustion, post combustion and conversion technology. Utilities are considering installing new scrubbers, switching fuel or possibly deep clean. However, the time required to implement the control technology is short. Due to the legislation, about 110 plants will have to adopt one of the approaches. This paper reports that in characterization of coal, Ames Laboratory used a scanning electron microscope- based, automated image analysis (SEM-AIA) technique to identify coal and mineral matter association. Various forms of organic sulfur were identified using peroxyacetic acid oxidation of coal. This was followed by subsequent microscopic, GC-MS, and HRMS analysis by Southern Illinois University. In ultrafine grinding of coal, it was reported by the Mining and Mineral Institute of Alabama that silica sand or flint shot used less energy compared to steel ball mills

  14. Balance of natural radionuclides in the brown coal based power generation and harmlessness of the residues and side product utilization; Bilanz natuerlicher Radionuklide in der Braunkohleverstromung und Unbedenklichkeit bei der Verwendung von Rueckstaenden und Nebenprodukten

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, Hartmut; Kunze, Christian; Hummrich, Holger [IAF-Radiooekologie GmbH, Radeberg (Germany)

    2017-04-01

    During brown coal combustion a partial enrichment of natural radionuclides occurs in different residues. Residues and side product from brown coal based power generation are used in different ways, for example filter ashes and gypsum from flue gas desulfurization facilities are used in the construction materials fabrication and slags for road construction. Detailed measurement and accounting of radionuclides in the mass throughputs in coal combustion power plants have shown that the utilized gypsum and filter ashes are harmless in radiologic aspects.

  15. Progress and performance of on-line analyzers of coal

    International Nuclear Information System (INIS)

    Spencer, C.M.; Brown, D.R.; Gozani, T.; Bozorgmanesh, H.; Bernatowicz, H.; Tassicker, O.J.; Karlson, F.

    1982-01-01

    This paper describes the past year's progress in the laboratory testing of the most comprehensive Nucoalyzer, the CONAC, and the performance of a Nucoalyzer-Sulfurmeter in special field tests. Previous papers and presentations provide more detailed background information. The near real-time analysis provided by a Nucoalyzer can be used in a variety of strategies to optimize efficiency of coal use. Nucoalyzers can be used to monitor coal deliveries and achieve uniformity in coal storage and recovery. In a coal cleaning plant, on-line analysis with a Nucoalyzer can lead to optimum Btu recovery while meeting specifications for the washed coal. A Nucoalyzer can monitor the blending of different coals to maintain a key cosntituent such as sulfur below a specified level, or can predict sulfur dioxide emissions, allowing feed-forward control to gas scrubbers and precipitators. Variability in coal feed to the boiler can lead to gross changes in thermodynamic efficiency in combustion. In addition, fouling and slagging incidents due to poor coal quality cause costly boiler shutdowns and maintenance. Nucoalyzer monitoring of key constituents and Btu in the coal feed allows operators to adjust boiler parameters for increased efficiency. To summarize, the primary advantages of Nucoalyzers relate to their ability to quickly identify changes in coal composition so that adjustments can be made in a timely manner to accommodate these changes in the process being monitored. Nucoalyzers are the only instruments available that can monitor the coal (for ash, Btu, sulfur, etc.) on-line and provide real-time continuous results. One Nucoalyzer is already working in the field, and by the time of the next Symposium we will have had performance reports on two more

  16. Distilling coal

    Energy Technology Data Exchange (ETDEWEB)

    Blythe, F C

    1914-09-14

    In the destructive distillation of bituminous coal, heavy hydrocarbon oil, such as petroleum, kerosine, shale oil, and heavy tar oil, obtained in some cases during the process, is added to the coal, which is then distilled under pressure and at a comparatively low temperature regulated so as to produce a large proportion of hydrocarbon oils and a small proportion of permanent gas. In one method, about 5 to 10 parts of hydrocarbon oil are mixed with 100 parts of crushed or ground coal, and the mixture is heated in a closed vessel, provided in some cases with an agitator, under a pressure of about 60 lb/in/sup 2/, and the temperature may be gradually raised to 350/sup 0/C and then to about 500/sup 0/C. The heating may be by means of superheated steam with or without external heat.

  17. Study on the Effect of Straw Fiber on the Performance of Volcanic Slag Concrete

    Science.gov (United States)

    Xiao, Li-guang; Liu, Xi-xu

    2018-03-01

    In this paper, the effects of straw fiber on the working performance, mechanical properties and frost resistance of volcanic slag lightweight aggregate concrete were studied. The experimental results show that the straw fiber is subjected to surface carbonization treatment and mixed into the volcanic slag light aggregate concrete. The flexural strength and fracture pressure ratio of volcanic slag lightweight aggregate concrete are improved obviously Improved volcanic slag lightweight aggregate concrete brittleness improves toughness. Carbonized straw fiber greatly improves the frost resistance of volcanic slag lightweight aggregate concrete. So that the volcanic slag light aggregate concrete freeze-thaw cycle can reach 300 times.

  18. Chemical durability of slag produced by thermal plasma melting of low-level miscellaneous solid wastes. Effects of slag composition

    International Nuclear Information System (INIS)

    Amakawa, Tadashi; Yasui, Shinji

    2001-01-01

    Low-level radioactive miscellaneous solid wastes are generated from commercial operation of nuclear power plants and will be generated from decommissioning of nuclear power plants in future. Static leaching tests were carried out in deionized water of 10degC on slag obtained by thermal plasma melting of simulating materials of the miscellaneous solids wastes with surrogate elements of radionuclides. It is found that logarithm of normalized elemental mass loss from the slag is proportional to the basicity represented by mole fractions of main structural oxides of the slag, such as SiO 2 , Al 2 O 3 , CaO, FeO and MgO. The range of static leaching rates from the slag is determined based on the above results and the basicity range of the miscellaneous solid wastes. Then we compared the leaching rates form the slag and from high level waste glasses. On these grounds, we concluded that the slag obtained by thermal plasma melting of miscellaneous solid wastes can stabilize radio-nuclides in it by no means inferior to the high level waste glasses. (author)

  19. Pathways of thirty-seven trace elements through coal-fired power plant

    International Nuclear Information System (INIS)

    Klein, D.H.; Andren, A.W.; Carter, J.A.; Emery, J.F.; Feldman, C.; Fulkerson, W.; Lyon, W.S.; Ogle, J.C.; Talmi, Y.; Van Hook, R.I.; Bolton, N.

    1975-01-01

    Coal, fly ash, slag, and combustion gases from a large cyclone-fed power plant 870 MW(e) were analyzed for a suite of elements. Mass balance calculations show that the sampling and analyses were generally adequate to describe the flows of these elements through the plant. Most Hg, some Se, and probably most Cl and Br were discharged to the atmosphere as gases. As, Cd, Cu, Ga, Mo, Pb, Sb, Se, and Zn were quite concentrated in fly ash compared to the slag, and were more concentrated in the ash discharged through the stack than in that collected by the precipitator. Al, Ba, Ca, Ce, Co, Eu, Fe, Hf, K, La, Mg, Mn, Rb, Sc, Si, Sm, Sr, Ta, Th, and Ti show little preferential partitioning between the slag and the collected or discharged fly ash. Cr, Sc, Na, Ni, U, and V exhibit behavior intermediate between the latter two groups

  20. Low-rank coal research. Final technical report, April 1, 1988--June 30, 1989, including quarterly report, April--June 1989

    Energy Technology Data Exchange (ETDEWEB)

    1989-12-31

    This work is a compilation of reports on ongoing research at the University of North Dakota. Topics include: Control Technology and Coal Preparation Research (SO{sub x}/NO{sub x} control, waste management), Advanced Research and Technology Development (turbine combustion phenomena, combustion inorganic transformation, coal/char reactivity, liquefaction reactivity of low-rank coals, gasification ash and slag characterization, fine particulate emissions), Combustion Research (fluidized bed combustion, beneficiation of low-rank coals, combustion characterization of low-rank coal fuels, diesel utilization of low-rank coals), Liquefaction Research (low-rank coal direct liquefaction), and Gasification Research (hydrogen production from low-rank coals, advanced wastewater treatment, mild gasification, color and residual COD removal from Synfuel wastewaters, Great Plains Gasification Plant, gasifier optimization).

  1. Alteration of municipal and industrial slags under atmospheric conditions

    Science.gov (United States)

    Rafał Kowalski, Piotr; Michalik, Marek

    2014-05-01

    The Waste Management System in Poland is being consequently built since 1998. After important changes in legislation, local governments have taken over the duty of waste collection. New points of selective collection of wastes have been opened and new sorting and composting plants were built. The last stage of introducing the Waste Management System is construction of waste incineration power plants. From nine installations which were planned, six are now under construction and they will start operating within the next two years. It is assumed that the consumption of raw wastes for these installations will reach 974 thousand tons per year. These investments will result in increased slags and ashes production. Now in Poland several local waste incinerators are operating and predominant amount of produced incineration residues is landfilled. These materials are exposed to atmospheric conditions in time of short term storage (just after incineration) and afterwards for a longer period of time on the landfill site. During the storage of slags low temperature mineral transformations and chemical changes may occur and also some components can be washed out. These materials are stored wet because of the technological processes. The aim of this study is to investigate the influence of storage in atmospheric conditions on slags from incineration of industrial and municipal wastes. The experiment started in January 2013. During this period slag samples from incineration of industrial and municipal wastes were exposed to atmospheric conditions. Samples were collected after 6 and 12 months. Within this time the pH value was measured monthly, and during the experimental period remained constant on the level of 9.5. After 6 months of exposure only slight changes in mineral compositions were observed in slags. The results of XRD analysis of municipal slags showed increase in content of carbonate minerals in comparison to the raw slag samples. In industrial slags, a decrease in

  2. Gasification Studies Task 4 Topical Report, Utah Clean Coal Program

    Energy Technology Data Exchange (ETDEWEB)

    Whitty, Kevin [Univ. of Utah, Salt Lake City, UT (United States); Fletcher, Thomas [Univ. of Utah, Salt Lake City, UT (United States); Pugmire, Ronald [Univ. of Utah, Salt Lake City, UT (United States); Smith, Philip [Univ. of Utah, Salt Lake City, UT (United States); Sutherland, James [Univ. of Utah, Salt Lake City, UT (United States); Thornock, Jeremy [Univ. of Utah, Salt Lake City, UT (United States); Hunsacker, Isaac [Univ. of Utah, Salt Lake City, UT (United States); Li, Suhui [Univ. of Utah, Salt Lake City, UT (United States); Kelly, Kerry [Univ. of Utah, Salt Lake City, UT (United States); Puntai, Naveen [Univ. of Utah, Salt Lake City, UT (United States); Reid, Charles [Univ. of Utah, Salt Lake City, UT (United States); Schurtz, Randy [Univ. of Utah, Salt Lake City, UT (United States)

    2011-10-01

    A key objective of the Task 4 activities has been to develop simulation tools to support development, troubleshooting and optimization of pressurized entrained-flow coal gasifiers. The overall gasifier models (Subtask 4.1) combine submodels for fluid flow (Subtask 4.2) and heat transfer (Subtask 4.3) with fundamental understanding of the chemical (Subtask 4.4) and physical (Subtask 4.5) processes that take place as coal particles are converted to synthesis gas and slag. However, it is important to be able to compare predictions from the models against data obtained from actual operating coal gasifiers, and Subtask 4.6 aims to provide an accessible, non-proprietary system, which can be operated over a wide range of conditions to provide well-characterized data for model validation.

  3. Japanese steel mills update and expectations to Canadian coal industry

    International Nuclear Information System (INIS)

    Yamaguchi, I.

    2008-01-01

    Kobe Steel's (Kobelco) corporate strategy includes expanding from only-one product such as high tensile strength steel sheet, and enlarging overseas production capacity through joint ventures and technical alliances. A new steel making process from low quality iron ore and steaming coal called ITmk3 has been developed by Kobe Steel that does not require any coke, reduces carbon dioxide emissions by 20 per cent, and reduces the cost of transporting slag. This strategy and technology was presented along with the changes surrounding the Japanese steel industry and raw materials market. These changes include the rise of emerging oil-producing countries; world steel production and exports; the rise in prices of resources; and the slowdown of the United States economy. The current situation of Japanese crude steel production, pig-iron production, and coke expansion plans were also presented. The presentation also outlined expectation's of the Canadian coal industry with reference to Canadian coal imports to Japan. tabs., figs

  4. The Healy Clean Coal Project: Design verification tests

    International Nuclear Information System (INIS)

    Guidetti, R.H.; Sheppard, D.B.; Ubhayakar, S.K.; Weede, J.J.; McCrohan, D.V.; Rosendahl, S.M.

    1993-01-01

    As part of the Healy Clean Coal Project, TRW Inc., the supplier of the advanced slagging coal combustors, has successfully completed design verification tests on the major components of the combustion system at its Southern California test facility. These tests, which included the firing of a full-scale precombustor with a new non-storage direct coal feed system, supported the design of the Healy combustion system and its auxiliaries performed under Phase 1 of the project. Two 350 million BTU/hr combustion systems have been designed and are now ready for fabrication and erection, as part of Phase 2 of the project. These systems, along with a back-end Spray Dryer Absorber system, designed and supplied by Joy Technologies, will be integrated with a Foster Wheeler boiler for the 50 MWe power plant at Healy, Alaska. This paper describes the design verification tests and the current status of the project

  5. Elemental properties of copper slag and measured airborne exposures at a copper slag processing facility.

    Science.gov (United States)

    Mugford, Christopher; Gibbs, Jenna L; Boylstein, Randy

    2017-08-01

    In 1974, the National Institute for Occupational Safety and Health recommended a ban on the use of abrasives containing >1% silica, giving rise to abrasive substitutes like copper slag. We present results from a National Institute for Occupational Safety and Health industrial hygiene survey at a copper slag processing facility that consisted of the collection of bulk samples for metals and silica; and full-shift area and personal air samples for dust, metals, and respirable silica. Carcinogens, suspect carcinogens, and other toxic elements were detected in all bulk samples, and area and personal air samples. Area air samples identified several areas with elevated levels of inhalable and respirable dust, and respirable silica: quality control check area (236 mg/m 3 inhalable; 10.3 mg/m 3 respirable; 0.430 mg/m 3 silica), inside the screen house (109 mg/m 3 inhalable; 13.8 mg/m 3 respirable; 0.686 mg/m 3 silica), under the conveyor belt leading to the screen house (19.8 mg/m 3 inhalable), and inside a conveyor access shack (11.4 mg/m 3 inhalable; 1.74 mg/m 3 respirable; 0.067 mg/m 3 silica). Overall, personal dust samples were lower than area dust samples and did not exceed published occupational exposure limits. Silica samples collected from a plant hand and a laborer exceeded the American Conference of Governmental Industrial Hygienist Threshold Limit Value of 0.025 µg/m 3 . All workers involved in copper slag processing (n = 5) approached or exceeded the Occupational Safety and Health Administration permissible exposure limit of 10 µg/m 3 for arsenic (range: 9.12-18.0 µg/m 3 ). Personal total dust levels were moderately correlated with personal arsenic levels (R s = 0.70) and personal respirable dust levels were strongly correlated with respirable silica levels (R s = 0.89). We identified multiple areas with elevated levels of dust, respirable silica, and metals that may have implications for personal exposure at other facilities if preventive

  6. Environmental Life Cycle Assessment of Coal-Biomass to Liquid Jet Fuel Compared to Petroleum-Derived JP-8 Jet Fuel

    Science.gov (United States)

    2010-03-01

    is a Metal Deactivator Additive (MDA) to prevent fuel oxidation with trace metals such as copper or zinc that may be in the jet fuel (MIL- HDBK-510-1...react in the FT synthesis process). The gasifier is of the slagging type and a direct contact water quench spray system is used to cool the syngas...exiting the gasifier. The quench also removes particulate matter and contaminants not removed in the slag . However, because the ash from biomass is

  7. Analysis of the Optimum Usage of Slag for the Compressive Strength of Concrete.

    Science.gov (United States)

    Lee, Han-Seung; Wang, Xiao-Yong; Zhang, Li-Na; Koh, Kyung-Taek

    2015-03-18

    Ground granulated blast furnace slag is widely used as a mineral admixture to replace partial Portland cement in the concrete industry. As the amount of slag increases, the late-age compressive strength of concrete mixtures increases. However, after an optimum point, any further increase in slag does not improve the late-age compressive strength. This optimum replacement ratio of slag is a crucial factor for its efficient use in the concrete industry. This paper proposes a numerical procedure to analyze the optimum usage of slag for the compressive strength of concrete. This numerical procedure starts with a blended hydration model that simulates cement hydration, slag reaction, and interactions between cement hydration and slag reaction. The amount of calcium silicate hydrate (CSH) is calculated considering the contributions from cement hydration and slag reaction. Then, by using the CSH contents, the compressive strength of the slag-blended concrete is evaluated. Finally, based on the parameter analysis of the compressive strength development of concrete with different slag inclusions, the optimum usage of slag in concrete mixtures is determined to be approximately 40% of the total binder content. The proposed model is verified through experimental results of the compressive strength of slag-blended concrete with different water-to-binder ratios and different slag inclusions.

  8. Characterization of Ladle Furnace Slag from Carbon Steel Production as a Potential Adsorbent

    Directory of Open Access Journals (Sweden)

    Ankica Rađenović

    2013-01-01

    Full Text Available A promising type of steel slag for applications is the ladle furnace (LF slag, which is also known as the basic slag, the reducing slag, the white slag, and the secondary refining slag. The LF slag is a byproduct from further refining molten steel after coming out of a basic oxygen furnace (BOF or an electric arc furnace (EAF. The use of the LF slag in further applications requires knowledge of its characteristics. The LF slag characterization in this paper has been performed using the following analytical methods: chemical analysis by energy dispersive spectrometry (EDS, mineralogical composition by X-ray diffraction (XRD, surface area properties by the Brunauer-Emmett-Teller (BET and the Barrett-Joyner-Halenda (BJH methods, surface chemistry by infrared absorption (FTIR spectroscopy, and morphological analysis by scanning electron microscopy (SEM. The results showed that the main compounds are calcium, silicon, magnesium, and aluminium oxides, and calcium silicates under their various allotropic forms are the major compounds in the LF slag. Surface area properties have shown that the LF slag is a mesoporous material with relatively great BET surface area. The ladle furnace slag is a nonhazardous industrial waste because the ecotoxicity evaluation by its eluate has shown that the LF slag does not contain constituents which might in any way affect the environment harmfully.

  9. Spray cooling

    International Nuclear Information System (INIS)

    Rollin, Philippe.

    1975-01-01

    Spray cooling - using water spraying in air - is surveyed as a possible system for make-up (peak clipping in open circuit) or major cooling (in closed circuit) of the cooling water of the condensers in thermal power plants. Indications are given on the experiments made in France and the systems recently developed in USA, questions relating to performance, cost and environmental effects of spray devices are then dealt with [fr

  10. FY 1992 report on the results of the development of an entrained bed coal gasification power plant. Part 3. Operation test of pilot plant (1/2); 1992 nendo seika hokokusho. Funryusho sekitan gaska hatsuden plant kaihatsu - Sono 3. Pilot plant unten shiken hen (1/2)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-02-01

    The study of operation test was made of the 200 t/d entrained bed coal gasification pilot plant that was constructed with the aim of establishing technology of the integrated coal gasification combined cycle power generation, and the details of the FY 1992 results were summarized. At RUN 10, conducted were the confirmation of the quantity of state of gasifier in the coal-fired high load operation and coal-fired constant load operation, and slagging survey. At RUN 11, the evaluation made after the work for prevention of slagging, and confirmation of the quantity of state of gasifier at a load of 80% heat input. At RUN 12, the evaluation of the measures taken against slagging, and test on the high load stable operation. At RUN 13, the evaluation of the measures taken against slagging, and large combustor response/total pressure control response tests. At RUN D1, test on the change of coal kind from A coal to D coal, and test on the initial adjusting operation of D coal. In the trial operation of these, the following were generated and the preventive measures were studied: impossibility of circulation of desulfurizing agent in gas refining facilities (dry desulfurizing system), bolt fracture of gas refining facilities (separator of dedusting facilities). (NEDO)

  11. Distribution of Clay Minerals in Light Coal Fractions and the Thermal Reaction Products of These Clay Minerals during Combustion in a Drop Tube Furnace

    Directory of Open Access Journals (Sweden)

    Sida Tian

    2016-06-01

    Full Text Available To estimate the contribution of clay minerals in light coal fractions to ash deposition in furnaces, we investigated their distribution and thermal reaction products. The light fractions of two Chinese coals were prepared using a 1.5 g·cm−3 ZnCl2 solution as a density separation medium and were burned in a drop-tube furnace (DTF. The mineral matter in each of the light coal fractions was compared to that of the relevant raw coal. The DTF ash from light coal fractions was analysed using hydrochloric acid separation. The acid-soluble aluminium fractions of DTF ash samples were used to determine changes in the amorphous aluminosilicate products with increasing combustion temperature. The results show that the clay mineral contents in the mineral matter of both light coal fractions were higher than those in the respective raw coals. For the coal with a high ash melting point, clay minerals in the light coal fraction thermally transformed more dehydroxylation products compared with those in the raw coal, possibly contributing to solid-state reactions of ash particles. For the coal with a low ash melting point, clay minerals in the light coal fraction produced more easily-slagging material compared with those in the raw coal, playing an important role in the occurrence of slagging. Additionally, ferrous oxide often produces low-melting substances in coal ash. Due to the similarities of zinc oxide and ferrous oxide in silicate reactions, we also investigated the interactions of clay minerals in light coal fractions with zinc oxide introduced by a zinc chloride solution. The extraneous zinc oxide could react, to a small extent, with clay minerals in the coal during DTF combustion.

  12. Artificial neural networks application for solid fuel slagging intensity predictions

    Directory of Open Access Journals (Sweden)

    Kakietek Sławomir

    2017-01-01

    Full Text Available Slagging issues present in pulverized steam boilers very often lead to heat transfer problems, corrosion and not planned outages of boilers which increase the cost of energy production and decrease the efficiency of energy production. Slagging especially occurs in regions with reductive atmospheres which nowadays are very common due to very strict limitations in NOx emissions. Moreover alternative fuels like biomass which are also used in combustion systems from two decades in order to decrease CO2 emissions also usually increase the risk of slagging. Thus the prediction of slagging properties of fuels is not the minor issue which can be neglected before purchasing or mixing of fuels. This however is rather difficult to estimate and even commonly known standard laboratory methods like fusion temperature determination or special indexers calculated on the basis of proximate and ultimate analyses, very often have no reasonable correlation to real boiler fuel behaviour. In this paper the method of determination of slagging properties of solid fuels based on laboratory investigation and artificial neural networks were presented. A fuel data base with over 40 fuels was created. Neural networks simulations were carried out in order to predict the beginning temperature and intensity of slagging. Reasonable results were obtained for some of tested neural networks, especially for hybrid feedforward networks with PCA technique. Consequently neural network model will be used in Common Intelligent Boiler Operation Platform (CIBOP being elaborated within CERUBIS research project for two BP-1150 and BB-1150 steam boilers. The model among others enables proper fuel selection in order to minimize slagging risk.

  13. Capital cost: high and low sulfur coal plants-1200 MWe. [High sulfur coal

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    This Commercial Electric Power Cost Study for 1200 MWe (Nominal) high and low sulfur coal plants consists of three volumes. The high sulfur coal plant is described in Volumes I and II, while Volume III describes the low sulfur coal plant. The design basis and cost estimate for the 1232 MWe high sulfur coal plant is presented in Volume I, and the drawings, equipment list and site description are contained in Volume II. The reference design includes a lime flue gas desulfurization system. A regenerative sulfur dioxide removal system using magnesium oxide is also presented as an alternate in Section 7 Volume II. The design basis, drawings and summary cost estimate for a 1243 MWe low sulfur coal plant are presented in Volume III. This information was developed by redesigning the high sulfur coal plant for burning low sulfur sub-bituminous coal. These coal plants utilize a mechanical draft (wet) cooling tower system for condenser heat removal. Costs of alternate cooling systems are provided in Report No. 7 in this series of studies of costs of commercial electrical power plants.

  14. Radionuclide emissions from a coal-fired power plant

    International Nuclear Information System (INIS)

    Amin, Y.M.; Uddin Khandaker, Mayeen; Shyen, A.K.S.; Mahat, R.H.; Nor, R.M.; Bradley, D.A.

    2013-01-01

    Current study concerns measurement of radioactivity levels in areas surrounding a 2420 MW thermal power plant fueled predominantly by bituminous coal. The concentrations of 226 Ra, 232 Th and 40 K in onsite bottom-ash were found to be 139 Bq/kg, 108 Bq/kg and 291 Bq/kg, respectively, the levels for these radiolnuclides in soil decreasing with distance from the power plant. At the plant perimeter the respective radionuclide concentrations were 87 Bq/kg, 74 Bq/kg and 297 Bq/kg. In a nearby town, the corresponding concentrations were 104 Bq/kg, 52 Bq/kg and 358 Bq/kg, suggestive of use of TENORM affected soils. The mean radium equivalent activities (Ra eq ) in soil and ash sample in the town were 205 Bq/kg and 316 Bq/kg, respectively. The Kapar plant ash/slag appears to contain a higher level of TENORM than the world average. The degree of contamination is much higher inside the town where slag has been mixed with topsoil as landfill or as simple domestic waste. For the prevailing levels of exposure and a worst case senario, the predicted committed effective dose due to ingestion and inhalation for intake durations of 1- and 30 years would be 4.2 μSv and 220 μSv, respectively. - Highlights: • Detailed studies on naturally occuring radionuclide emissions due to a 2420 MW coal-fired power plant in Malaysia. • Assessment of radiation exposures to the public around the power plant due to an intake of the radionuclides. • The Kapar plant ash/slag appears to contain a higher level of TENORM than the world average. • The degree of contamination is much higher inside the town where slag has been mixed with topsoil as landfill or as simple domestic waste

  15. Coal Mines Security System

    OpenAIRE

    Ankita Guhe; Shruti Deshmukh; Bhagyashree Borekar; Apoorva Kailaswar; Milind E.Rane

    2012-01-01

    Geological circumstances of mine seem to be extremely complicated and there are many hidden troubles. Coal is wrongly lifted by the musclemen from coal stocks, coal washeries, coal transfer and loading points and also in the transport routes by malfunctioning the weighing of trucks. CIL —Coal India Ltd is under the control of mafia and a large number of irregularities can be contributed to coal mafia. An Intelligent Coal Mine Security System using data acquisition method utilizes sensor, auto...

  16. Coal at the crossroads

    International Nuclear Information System (INIS)

    Scaroni, A.W.; Davis, A.; Schobert, H.; Gordon, R.L.; Ramani, R.V.; Frantz, R.L.

    1992-01-01

    Worldwide coal reserves are very large but coal suffers from an image of being an environmentally unfriendly and inconvenient fuel. Aspects discussed in the article include: coal's poor image; techniques for coal analysis, in particular instrumented techniques; developments in clean coal technology e.g. coal liquefaction, fluidized bed combustion, co-generation and fuel slurries; the environmental impact of mining and land reclamation; and health aspects. It is considered that coal's future depends on overcoming its poor image. 6 photos

  17. High temperature slagging incineration of hazardous waste

    International Nuclear Information System (INIS)

    Vanbrabant, R.; Van de Voorde, N.

    1987-01-01

    The SCK/CEN, as the treatment center for the low level radioactive waste in Belgium, develops appropriate treatment systems for different kinds of wastes. The technical concept of the high temperature slagging incineration system has been developed and improved. The construction of the first demonstration plant was initiated in 1974. Since then the system has been operated regularly and further developed with the view to industrial operations. Now it handles about 5 tons of waste in a week. The waste which is treated consists of low level beta/gamma and alpha-contaminated radioactive waste. Because of the special characteristics the system is thought to be an excellent incineration system for industrial hazardous waste as well. Recently the SCK/CEN has received the authorization to treat industrial hazardous waste in the same installation. Preliminary tests have been executed on special waste products, such as PCB-contaminated liquids, with excellent incineration results. Incineration efficiency up to 99.9999% could be obtained. The paper presents the state of the art of this original The SCK/CEN-technology and gives the results of the tests done with special hazard

  18. Survey report for fiscal 1999 on internationalization of technologies for effective use of energy resources. Survey by exploration of international cooperative researches on energy-saving through advanced use of steel slag; 1999 nendo energy shigen yuko riyo gijutsu kenkyu kokusaika chosa hokokusho. Tekko slag no kodo riyo ni yoru sho energy gijutsu ni kansuru kokusai kyodo kenkyu no tansaku chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    As for the collection of sensible heat, 1/3 of blast-furnace slag is treated to the purpose at the Teesside Technology Centre, Britain, but none is collected in the latter half of tapping in case there is so much slag that cooling cannot be done in time. In the case of a large blast furnace, some measures have to be contrived because molten iron comes out of the furnace intermittently. In Germany, the heat collection rate is as low as 3%, with no effort made at heat collection. In North America, desire to develop such a technology is not strong. A visit was made to the Institute of Ocean Sciences, Canada, in relation to the concept of using steel slag as a eutrophic source for marine photo-plankton. A large-scale long-term test is under way for examining the relationship between global warming and ocean current circulation. There are possibilities that Japan will enter into the project for a joint study, for example, of heavy metal elution from slag though the test fails to name slag as the direct object of study. Not only for Canada but also for any other country who faces the sea, it may be a meaningful national policy to inject some active ingredients into the sea for an increase in living marine resources. Greece is engaged in the ocean dumping of nickel slag on an experimental basis but, in view of the purpose of the experiment, Japan will not be a participant in the project. (NEDO)

  19. Use of soil-steel slag-class-C fly ash mixtures in subgrade applications.

    Science.gov (United States)

    2012-12-07

    In Indiana, large quantities of recyclable : materials - such as steel slag, blast furnace : slag and fly ash - are generated each year as : by-products of various industries. Instead of : disposing these by-products into landfills, : we can recycle ...

  20. Crystallization characteristics of iron-rich glass ceramics prepared from nickel slag and blast furnace slag

    Science.gov (United States)

    Wang, Zhong-Jie; Ni, Wen; Li, Ke-Qing; Huang, Xiao-Yan; Zhu, Li-Ping

    2011-08-01

    The crystallization process of iron-rich glass-ceramics prepared from the mixture of nickel slag (NS) and blast furnace slag (BFS) with a small amount of quartz sand was investigated. A modified melting method which was more energy-saving than the traditional methods was used to control the crystallization process. The results show that the iron-rich system has much lower melting temperature, glass transition temperature ( T g), and glass crystallization temperature ( T c), which can result in a further energy-saving process. The results also show that the system has a quick but controllable crystallization process with its peak crystallization temperature at 918°C. The crystallization of augite crystals begins from the edge of the sample and invades into the whole sample. The crystallization process can be completed in a few minutes. A distinct boundary between the crystallized part and the non-crystallized part exists during the process. In the non-crystallized part showing a black colour, some sphere-shaped augite crystals already exist in the glass matrix before samples are heated to T c. In the crystallized part showing a khaki colour, a compact structure is formed by augite crystals.

  1. Products of steel slags an opportunity to save natural resources.

    Science.gov (United States)

    Motz, H; Geiseler, J

    2001-01-01

    In Germany, and in the most industrial countries, the use of blast furnace and steel slags as an aggregate for civil engineering, for metallurgical use and as fertiliser has a very long tradition. Since the introduction of the basic oxygen steel making furnace (BOF) process and the electric arc furnace (EAF) process the German steel industry started extensive research on the development of fields of application for BOF and EAF slags. These investigations have been mainly performed by Forschungsgemeinschaft Eisenhüttenschlacken e. V. (FEhS), the Research Association for blast furnace and steel slags. Today steel slags are well characterised and long-term experienced materials mainly used as aggregates for road construction (e.g. asphaltic or unbound layers), as armour-stones for hydraulic engineering constructions (e.g. stabilisation of shores), and as fertiliser for agriculture purposes. These multifarious fields of application could only be achieved because the steelworks influence the quality of slags by a careful selection of raw materials and a suitable process route. Furthermore, subsequent procedures like a treatment of the liquid slag, an appropriate heat treatment and a suitable processing have been developed to ensure that the quality of steel slags is always adequate for the end use. Depending on the respective field of application, the suitability of steel slags has to be proven by determining the technical properties, as well as the environmental compatibility. For this reason test methods have been developed to evaluate the technical properties especially the volume stability and the environmental behaviour. To evaluate the volume stability a suitable test (steam test) has been developed and the results from laboratory tests were compared with the behaviour of steel slags under practical conditions, e.g. in a road. To determine the environmental behaviour leaching tests have been developed. In the meanwhile most of these test methods are drafted or

  2. Nickel, copper and cobalt coalescence in copper cliff converter slag

    Directory of Open Access Journals (Sweden)

    Wolf A.

    2016-01-01

    Full Text Available The aim of this investigation is to assess the effect of various additives on coalescence of nickel, copper and cobalt from slags generated during nickel extraction. The analyzed fluxes were silica and lime while examined reductants were pig iron, ferrosilicon and copper-silicon compound. Slag was settled at the different holding temperatures for various times in conditions that simulated the industrial environment. The newly formed matte and slag were characterized by their chemical composition and morphology. Silica flux generated higher partition coefficients for nickel and copper than the addition of lime. Additives used as reducing agents had higher valuable metal recovery rates and corresponding partition coefficients than fluxes. Microstructural studies showed that slag formed after adding reductants consisted of primarily fayalite, with some minute traces of magnetite as the secondary phase. Addition of 5 wt% of pig iron, ferrosilicon and copper-silicon alloys favored the formation of a metallized matte which increased Cu, Ni and Co recoveries. Addition of copper-silicon alloys with low silicon content was efficient in copper recovery but coalescence of the other metals was low. Slag treated with the ferrosilicon facilitated the highest cobalt recovery while copper-silicon alloys with silicon content above 10 wt% resulted in high coalescence of nickel and copper, 87 % and 72 % respectively.

  3. BUILDING MATERIALS AND PRODUCTS BASED ON SILICON MANGANESE SLAGS

    Directory of Open Access Journals (Sweden)

    BOLSHAKOV V. I.

    2016-05-01

    Full Text Available Raising of problem. Currently of particular relevance was given to the matter of introduction in manufacture of building materials and products, resource-saving techniques and technologies; integrated use of raw materials and materials that prevent or significantly reduce their harmful impact on the environment. This allows you to recycle hundreds of thousands of tons of the fiery liquid slags of silicon manganese and to develop effective structural materials that can replace metals, non-metallic building materials of natural origin, concretes, cast stone, plastics and refractories. Purpose. The study of the structure and properties of building materials and products from electric furnace slag of silicon manganese. Conclusion. Slags from the smelting of silicon manganese are classified as acidic. Their lime factor is in the range of 0.47–0.52. The composition of the slag located in the heterogeneous region SiO2 near the line of separation of cristobalite spread to the crystallization of wollastonite, according to the ternary system MnO-CaO-SiO2, which in consideration of their stability, allows the development of technology of building materials (gravel, sand, granulated slag, etc. and products (foundation blocks, road slabs, containers for transportation and storage of hazardous waste, and others.

  4. Pyrometallurgical slags as a potential source of selected metals recovery

    Directory of Open Access Journals (Sweden)

    K. Nowińska

    2014-10-01

    Full Text Available Complex analysis of concentration and form of occurrence such metals as Zn, Pb, Fe and Cu in slags formed during a current zinc production in the Imperial Smelting Process (ISP is a possible basis for development of optimal recovery technology. For this purpose studies of slags from the current production of the Shaft Furnace Unit and of the Lead Refining of the “Miasteczko Śląskie” Zinc Smelting Plant were carried out. The studies results show that slags includes high concentrations of: Zn from 0,064 % to 1,680 %, Pb from 10,56 % to 50,71 %, Fe from 0,015 % to 2,576 %, Cu from 7,48 % to 64,95 %, and change in a broad range. This slags show significant heterogeneity, caused by intermetallic phases (Zn - Pb, Cu - Zn, Cu - Pb formed on the surface thereof. It is so possible that slag can be a potential source of this metals recovery.

  5. Experimental Study on the Utilization of Fine Steel Slag on Stabilizing High Plastic Subgrade Soil

    OpenAIRE

    Hussien Aldeeky; Omar Al Hattamleh

    2017-01-01

    The three major steel manufacturing factories in Jordan dump their byproduct, steel slag, randomly in open areas, which causes many environmental hazardous problems. This study intended to explore the effectiveness of using fine steel slag aggregate (FSSA) in improving the geotechnical properties of high plastic subgrade soil. First soil and fine steel slag mechanical and engineering properties were evaluating. Then 0%, 5%, 10%, 15%, 20%, and 25% dry weight of soil of fine steel slag (FSSA) w...

  6. Coal industry annual 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    Coal Industry Annual 1997 provides comprehensive information about US coal production, number of mines, prices, productivity, employment, productive capacity, and recoverable reserves. US Coal production for 1997 and previous years is based on the annual survey EIA-7A, Coal Production Report. This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report includes a national total coal consumption for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. 14 figs., 145 tabs.

  7. Coal industry annual 1997

    International Nuclear Information System (INIS)

    1998-12-01

    Coal Industry Annual 1997 provides comprehensive information about US coal production, number of mines, prices, productivity, employment, productive capacity, and recoverable reserves. US Coal production for 1997 and previous years is based on the annual survey EIA-7A, Coal Production Report. This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report includes a national total coal consumption for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. 14 figs., 145 tabs

  8. Coal marketing manual 1987

    Energy Technology Data Exchange (ETDEWEB)

    1987-01-01

    This manual provides information on the international coal market in tabulated format. Statistics are presented for the Australian coal industry, exports, currency movements, world coal production, coal and coke imports and exports. Detailed information is provided on the Australian coal industry including mine specific summaries. Pricing summaries for thermal and coking coal in 1987, coal quality standards and specifications, trends in coal prices and stocks. Imports and exports for World coal and coke, details of shipping, international ports and iron and steel production. An exporters index of Australian and overseas companies with industry and government contacts is included. 15 figs., 67 tabs.

  9. Coal industry annual 1996

    International Nuclear Information System (INIS)

    1997-11-01

    This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality, and emissions for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States.This report does not include coal consumption data for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. Consumption for nonutility power producers not included in this report is estimated to be 24 million short tons for 1996. 14 figs., 145 tabs

  10. Coal industry annual 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-11-01

    This report presents data on coal consumption, coal distribution, coal stocks, coal prices, and coal quality, and emissions for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States.This report does not include coal consumption data for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. Consumption for nonutility power producers not included in this report is estimated to be 24 million short tons for 1996. 14 figs., 145 tabs.

  11. Coal Industry Annual 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    This report presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. Consumption for nonutility power producers not included in this report is estimated to be 21 million short tons for 1995.

  12. Coal Industry Annual 1995

    International Nuclear Information System (INIS)

    1996-10-01

    This report presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for Congress, Federal and State agencies, the coal industry, and the general public. Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility power producers that are not in the manufacturing, agriculture, mining, construction, or commercial sectors. Consumption for nonutility power producers not included in this report is estimated to be 21 million short tons for 1995

  13. Healy Clean Coal Project: A DOE Assessment

    Energy Technology Data Exchange (ETDEWEB)

    National Energy Technology Laboratory

    2003-09-01

    The goal of the U.S. Department of Energy's (DOE) Clean Coal Technology (CCT) Program is to provide the energy marketplace with advanced, more efficient, and environmentally responsible coal utilization options by conducting demonstrations of new technologies. These demonstration projects are intended to establish the commercial feasibility of promising advanced coal technologies that have been developed to a level at which they are ready for demonstration testing under commercial conditions. This document serves as a DOE post-project assessment (PPA) of the Healy Clean Coal Project (HCCP), selected under Round III of the CCT Program, and described in a Report to Congress (U.S. Department of Energy, 1991). The desire to demonstrate an innovative power plant that integrates an advanced slagging combustor, a heat recovery system, and both high- and low-temperature emissions control processes prompted the Alaska Industrial Development and Export Authority (AIDEA) to submit a proposal for this project. In April 1991, AIDEA entered into a cooperative agreement with DOE to conduct this project. Other team members included Golden Valley Electric Association (GVEA), host and operator; Usibelli Coal Mine, Inc., coal supplier; TRW, Inc., Space & Technology Division, combustor technology provider; Stone & Webster Engineering Corp. (S&W), engineer; Babcock & Wilcox Company (which acquired the assets of Joy Environmental Technologies, Inc.), supplier of the spray dryer absorber technology; and Steigers Corporation, provider of environmental and permitting support. Foster Wheeler Energy Corporation supplied the boiler. GVEA provided oversight of the design and provided operators during demonstration testing. The project was sited adjacent to GVEA's Healy Unit No. 1 in Healy, Alaska. The objective of this CCT project was to demonstrate the ability of the TRW Clean Coal Combustion System to operate on a blend of run-of-mine (ROM) coal and waste coal, while meeting strict

  14. Coal and Energy.

    Science.gov (United States)

    Bryant, Reba; And Others

    This teaching unit explores coal as an energy resource. Goals, student objectives, background information, and activity options are presented for each major section. The sections are: (1) an introduction to coal (which describes how and where coal was formed and explains the types of coal); (2) the mining of coal (including the methods and ways of…

  15. The hydration of slag, part 2: reaction models for blended cement

    NARCIS (Netherlands)

    Chen, Wei; Brouwers, H.J.H.

    2007-01-01

    The hydration of slag-blended cement is studied by considering the interaction between the hydrations of slag and Portland cement clinker. Three reaction models for the slag-blended cement are developed based on stoichiometric calculations. These models correlate the compositions of the unhydrated

  16. Determination of natural radionuclide level in industrial waste slags and evaluation of comprehensive utilization

    International Nuclear Information System (INIS)

    Li Ruixiang; Liu Xinhua; Gan Lin

    1994-09-01

    Natural radionuclide contents were measured in various industrial waste slags in China by a low background HPGe γ spectrometer and the radiological impact was estimated for some comprehensive utilization of these slags. Most waste slags can be used for building materials except for tailing and waste rock form nuclear industry

  17. Field test on sand compaction pile method with copper slag sand; Dosuisai slag wo mochiita SCP koho no shiken seko

    Energy Technology Data Exchange (ETDEWEB)

    Minami, K.; Matsui, H.; Naruse, E.; Kitazume, M. [Port and Harbour Research Inst., Kanagawa (Japan)

    1997-09-20

    This paper describes the sand compaction pile (SCP) method using copper slag sand. The SCP method is a method by which sand compaction piles are constructed in the ground, and improvement can be obtained in a short period. This method has been widely used even in the port areas for enhancing the bearing power of soft clay ground and the lateral resistance of sheet pile. A great deal of sand is required as a material. The sand requires high permeability, proper size distribution with less fine particle fraction content, easy compaction property with enough strength, and easy discharging property from the casing of construction machines as required properties. Recently, it becomes hard to secure proper sand materials. The copper slag sand is obtained from refining process of copper as a by-product which is quenched in water flow and crushed in water. The copper slag sand has higher particle density than that of sand, excellent permeability, and similar size distribution to that of sand. From compaction drainage triaxial compression test and permeability test, it was found that the mechanical properties of copper slag sand did not change by the crushing of grains with keeping excellent permeability. Through the test construction, applicability of the copper slag sand to the SCP method could be confirmed as an alternate material of sand. 17 refs., 9 figs., 4 tabs.

  18. Coal fired steam generation for heavy oil recovery

    International Nuclear Information System (INIS)

    Firmin, K.

    1992-01-01

    In Alberta, some 21,000 m 3 /d of heavy oil and bitumen are produced by in-situ recovery methods involving steam injection. The steam generation requirement is met by standardized natural-gas-fired steam generators. While gas is in plentiful supply in Alberta and therefore competitively priced, significant gas price increases could occur in the future. A 1985 study investigating the alternatives to natural gas as a fuel for steam generation concluded that coal was the most economic alternative, as reserves of subbituminous coal are not only abundant in Alberta but also located relatively close to heavy oil and bitumen production areas. The environmental performance of coal is critical to its acceptance as an alternate fuel to natural gas, and proposed steam generator designs which could burn Alberta coal and control emissions satisfactorily are assessed. Considerations for ash removal, sulfur dioxide sorption, nitrogen oxides control, and particulate emission capture are also presented. A multi-stage slagging type of coal-fired combustor has been developed which is suitable for application with oilfield steam generators and is being commissioned for a demonstration project at the Cold Lake deposit. An economic study showed that the use of coal for steam generation in heavy oil in-situ projects in the Peace River and Cold Lake areas would be economic, compared to natural gas, at fuel price projections and design/cost premises for a project timing in the mid-1990s. 7 figs., 3 tabs

  19. High-Temperatures Rheometric Analysis Of Selected Heterogeneous Slag Systems

    Directory of Open Access Journals (Sweden)

    Migas P.

    2015-06-01

    Full Text Available It is known that the dynamic viscosity coefficient of slag – with an increased titanium compounds content in the reducing conditions of the blast furnace - may rapidly change. The products of the reduction reaction, precipitation and separation of titanium compounds are responsible for the thickening effect of the slag and the problems of permeability of blast furnace, causing anomalies in the dipping zone. The presence of solid components (particles in the melts determines the rheological character of the entire system. Identifying the rheological character of semi-solid slag systems provides opportunities for the development of mathematical modeling of liquid phase flows in a dripping zone of the blast furnace, allowing e.g to indentify the unstable parts of a metallurgical aggregate.

  20. A Review of Granulation Process for Blast Furnace Slag

    Directory of Open Access Journals (Sweden)

    Yu Pengfei

    2016-01-01

    Full Text Available Molten slags of blast furnace is a second resources with great value of 1600~1 800 MJ sensible heat per ton. At present, water-quenching process plays a leading role in recovering waste heat of the molten slags. However, this method not only cost lots of water, but also recover little sensible heat and can pollute the surrounding environment. Dry granulation process, as an environmentally friendly method with high-efficiency heat recovery, have attracted widespread attentions. In this paper, the water quenching and dry granulation processes were discussed in detail. After a thorough comparative analysis of various treatment technologies, it can be concluded that centrifugal granulation affiliated with dry granulation is the optimum process, with smaller slag particle size (about 2mm, more glassy phase and higher recovery rate.

  1. Use of steel slag as a new material for roads

    Science.gov (United States)

    Ochoa Díaz, R.; Romero Farfán, M.; Cardenas, J.; Forero, J.

    2017-12-01

    This research paper aims to analyse the behaviour of MDC-19 hot dense asphalt mixtures with steel slag as coarse aggregate, by using asphalt 80-100, in order to verify if this residue has suitable characteristics that allow its use. The physical and mechanical characterization was accomplished using phosphorous slag from the company Acerías Paz del Río S.A. The working formula was then determined for each mixture using the RAMCODES methodology, the briquettes were produced in the laboratory and then, the design verification was performed. Taking into account the results obtained, it is concluded that the use of phosphorous slag as coarse aggregate in asphalt mixtures is workable, since acceptable design parameters and verification are obtained that meet the specifications for use as a rolling layer.

  2. Coal -94

    International Nuclear Information System (INIS)

    Sparre, C.

    1994-05-01

    This report deals with use of coal and coke during 1993; information about techniques, environmental questions and markets are also given. Use of steamcoal for heating purposes has been reduced about 3 % during 1993 to 1,0 mill tons. This is the case especially for the heat generating boilers. Production in co-generation plants has been constant and has increased for electricity production. Minor plants have increased their use of forest fuels, LPG and NG. Use of steamcoal will probably go down in the immediate years both in heat generating and co-generating plants. Coal-based electricity has been imported from Denmark during 1993 corresponding to about 400 000 tons of coal, when several of our nuclear plants were stopped. Use of steamcoal in the industry has been constant at 700 000 tons. This level is supposed to be constant or to vary with business cycles. The import of metallurgical coal in 1993 was 1,6 mill tons like the year before. 1,2 mill tons coke were produced. Coke consumption in industry was 1,4 mill tons. 0,2 mill tons of coke were imported. Average price of steamcoal imported to Sweden in 1993 was 308 SEK/ton or 13 % higher than in 1992; this can be explained by the dollar price level increasing 34% in 1993. For the world, the average import price was 50,0 USD/ton, a decrease of 6 %. The coal market during 1993 was affected by less consumption in Europe, shut downs of European mines and decreasing prices. High freight price raises in Russia has affected the Russian export and the market in northern Europe. The prices have been stabilized recently. All Swedish plants meet emission limits of dust, SO 2 and NO x . Co-generation plants all have some sort of SO 2 -removal system; the wet-dry method is mostly used. A positive effect of the recently introduced NO x -duties is a 40% reduction

  3. Quality of structural steel melted by single-slag process

    International Nuclear Information System (INIS)

    Levin, A.M.; Andreev, V.I.; Monastyrskij, A.V.; Drozdova, M.F.; Pashchenko, V.E.; Orzhekh, M.B.

    1982-01-01

    The 40Kh and 12KhN3A steels were used to compare the quality of the metal manufactured according to several variants of a single-slag process with the metal of a conventional melting technology. Investigation results show, that a single-slag process metal has higher sulfides and oxides contents as well as an increased anisotropy of mechanical properties while its tendency to flake formation is weaker due to a less degree of gas saturation. It is marked that anisotropy in the properties and a sulfide content may be decreased by out-of-furnace treatment of steels

  4. High temperature slagging incinerator for alpha contaminated wastes

    International Nuclear Information System (INIS)

    Van de Voorde, N.

    1985-01-01

    This report describes the experiences collected by the treatment of plutonium-contaminated wastes, in the High Temperature Slagging Incinerator at the C.E.N./S.C.K. at Mol, with the support of the Commission of the European Communities. The major objective of the exercise is to demonstrate the operability of this facility for the treatment of mixed transuranic (TRU) and beta-gamma solid waste material. The process will substantially reduce the TRU waste volume by burning the combustibles and converting the non-combustibles into a chemically inert and physically stable basalt-like slag product, suitable for safe transport and final disposal. (Auth.)

  5. Attenuation of Gamma Rays by Concrete . Lead Slag Composites

    International Nuclear Information System (INIS)

    Ismail, I.M.; Sweelam, M.H.; Zaghloul, Y.R.; Aly, H.F.

    2008-01-01

    Using of wastes and industrial by-products as concrete aggregate to be used as structural and radiation shielded material has increased in the recent years. Concrete was mixed with different amounts of lead slag extracted from recycling of the spent automotive batteries as fine aggregates. The lead slag was used as partial replacement of sand in the studied composites. The concrete composites obtained were characterized in terms of density, water absorption, porosity, compressive strength and attenuation of γ- rays with different energies. The attenuation coefficient and the half value thickness of the different matrices were calculated and discussed

  6. Coal statistics 1977

    Energy Technology Data Exchange (ETDEWEB)

    Statistical Office of the European Communities

    1978-01-01

    Presents tables of data relating to the coal market in the European Community in 1977. The tables cover hard coal production, supply and trade; briquettes; cokes; lignite, brown coal briquettes and peat; and mines and coke ovens.

  7. Australian coal yearbook 1989

    Energy Technology Data Exchange (ETDEWEB)

    Aylward, A [ed.

    1989-01-01

    This yearbook contains a mine directory; details of coal export facilities and ports; annual coal statistics; a buyers' guide; names and addresses of industry organisations and an index of coal mine owners.

  8. Coal industry annual 1993

    Energy Technology Data Exchange (ETDEWEB)

    1994-12-06

    Coal Industry Annual 1993 replaces the publication Coal Production (DOE/FIA-0125). This report presents additional tables and expanded versions of tables previously presented in Coal Production, including production, number of mines, Productivity, employment, productive capacity, and recoverable reserves. This report also presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for a wide audience including the Congress, Federal and State agencies, the coal industry, and the general public. In addition, Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility Power Producers who are not in the manufacturing, agriculture, mining, construction, or commercial sectors. This consumption is estimated to be 5 million short tons in 1993.

  9. Coal industry annual 1993

    International Nuclear Information System (INIS)

    1994-01-01

    Coal Industry Annual 1993 replaces the publication Coal Production (DOE/FIA-0125). This report presents additional tables and expanded versions of tables previously presented in Coal Production, including production, number of mines, Productivity, employment, productive capacity, and recoverable reserves. This report also presents data on coal consumption, coal distribution, coal stocks, coal prices, coal quality, and emissions for a wide audience including the Congress, Federal and State agencies, the coal industry, and the general public. In addition, Appendix A contains a compilation of coal statistics for the major coal-producing States. This report does not include coal consumption data for nonutility Power Producers who are not in the manufacturing, agriculture, mining, construction, or commercial sectors. This consumption is estimated to be 5 million short tons in 1993

  10. Commissioning an Engineering Scale Coal Gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Reid, Douglas J.; Bearden, Mark D.; Cabe, James E.

    2010-07-01

    This report explains the development, commissioning, and testing of an engineering scale slagging coal gasifier at PNNL. The initial objective of this project was to commission the gasifier with zero safety incidents. The commissioning work was primarily an empirical study that required an engineering design approach. After bringing the gasifier on-line, tests were conducted to assess the impact of various operating parameters on the synthesis gas (syngas) product composition. The long-term intent of this project is to produce syngas product for use by internal Pacific Northwest National Laboratory (PNNL) researchers in catalyst, materials, and instrumentation development. Future work on the project will focus on improving the reliability and performance of the gasifier, with a goal of continuous operation for greater than 4 hours using coal feedstock. In addition, alternate designs that allow for increased flexibility regarding the fuel sources that can be used for syngas production is desired. Continued modifications to the fuel feed system will be pursued to address these goals. Alternative feed mechanisms such as a coal/methanol slurry are being considered.

  11. Electrokinetics and flocculation studies of coal

    Energy Technology Data Exchange (ETDEWEB)

    Dhawan, N. [Punjab Engineering College, Chandigarh (India). Dept. of Metallurgical Engineering

    2008-07-01

    Coal from India contains 25-35 per cent ash content. This leads to high slag volume, lower calorific value and inferior coke. In order to remove ash content, coal is washed, however, it retains some water that makes it difficult to process. Mechanical dewatering is performed in which a large portion of solids is removed while the remainder remains in centrifuge. There is therefore a need to recover solids and water. This paper discussed the use of flocculation and electrokinetic studies such as the determination of the point of zero charge. The experimental studies considered factors such as turbidity, faster settling, and compactness. Flocculation is brought about by the action of high molecular weight materials such as polyelectrolytes, where the material physically forms a bridge between two or more particles, uniting the sold particles into a random, three-dimensional structure, which is loose and porous. This paper also described the materials and methods of the electrokinetic studies on coal samples. Materials that were described included nephelometer, zeta meter, and a flocculator. It was concluded that in selecting the best flocculant, the preference order should be turbidity; settling rate; dosage; and moisture content. 3 refs., 2 tabs., 8 figs.

  12. Australian black coal statistics 1990

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    This second edition of Australian black coal statistics replaces the Joint Coal Board's publication 'Black coal in Australia'. It includes an expanded international coal trade supplement. Sections cover resources of black coal, coal supply and demand, coal production, employment and productivity of mines, export data, coal consumption and a directory of producers.

  13. A Technique for Decreasing Reactivity of Coal Material to Suppress the Oxygen Absorption Process

    OpenAIRE

    Timofeeva, S. S.; Lugovtsova, Nataliya Yurievna; Gubanova, А. R.

    2016-01-01

    The paper describes the mechanisms of self-ignition formation in coal liable to spontaneous combustion, on the basis of experimental works performed to analyze heat and mass transfer in the coal-air system. A new approach was developed to the coal self-heating suppression and thermodynamic control of the oxidation process. The influence of coal moisture content and thermal behaviour of air in the cooling process was studied during moisture evaporation.

  14. Preparation of fly ash-granulated blast furnace slag-carbide slag binder and application in total tailings paste backfill

    Science.gov (United States)

    Li, Chao; Hao, Ya-fei; Zhao, Feng-qing

    2018-03-01

    Based on activation and synergistic effect among various materials, a low-cost mine backfill cementing material, FGC binder, was prepared by using fly ash, granulated blast-furnace slag (GBFS), carbide slag and composite activator. The proper proportioning of FGC binder is obtained by response surface experiment optimization method: fly ash 62 %, GBFS 20 %, carbide slag 8 % and compound activators 10 %. Adjusting the material ratio obtains different cementing material which could satisfy requirements of different mined-out areas. With the mass ratio of cementing material and tailings 1:4∼1:8, the concentration of total solid 70 %, the compressive strength values of total tailings filling body at 28 d reaches 1.64∼4.14 MPa, and the backfilling cost is 20 % lower than using OPC cement.

  15. Ventilative Cooling

    DEFF Research Database (Denmark)

    Heiselberg, Per Kvols; Kolokotroni, Maria

    This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state-of-the-art of ventil......This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state......-of-the-art of ventilative cooling potentials and limitations, its consideration in current energy performance regulations, available building components and control strategies and analysis methods and tools. In addition, the report provides twenty six examples of operational buildings using ventilative cooling ranging from...

  16. Influence of lithium slag from lepidolite on the durability of concrete

    Science.gov (United States)

    Qi, Luo; Shaowen, Huang; Yuxuan, Zhou; Jinyang, Li; Weiliang, Peng; Yufeng, Wen

    2017-04-01

    This paper mainly studies the effect of lithium slag from lepidolite on the property of concrete including dry shrinkage, anti-carbonation, wear resistance and chloride ion resistance. Concrete interface structure has been observed with SEM. The results show that adding lithium slag to concrete can improve concrete property including dry shrinkage, wear resistance and chloride ion resistance. However, the wear resistance tends to decrease when the amount of lithium slag reach 20%. Lithium slag also has negative effect on anti-carbonation property. With the increasing amount of lithium slag, anti-carbonation property of concrete decrease gradually.

  17. Steelmaking slag beneficiation by magnetic separator and impacts on sinter quality

    Directory of Open Access Journals (Sweden)

    Bölükbaşı Ö.S.

    2014-01-01

    Full Text Available Basic oxygen furnaces (BOF slag is the main problem at all iron and steel factories. About more than 6 million tons/year of BOF slag has been accumulated from the waste stockyards in Turkey. Dumps slags can be revaluated by a processing technology which makes it possible to obtain products that meet the requirements of sintering and blast furnace production. The slags with particle size of -10 mm were enriched by the magnetic separator resulting and increase in Fe grade from 18% to 33%. The use of BOF slag in sinter blend provided additional Mn, CaO, MgO and introduced a good solution to environmental problems.

  18. The electrical characteristics of copper slags in a 270 kVA DC arc furnace

    International Nuclear Information System (INIS)

    Derin, Bora; Sahin, Filiz Cinar; Yucel, Onuralp

    2003-01-01

    The electrical resistance of slags is the main criteria to determine the design and the operation conditions of slag resistance furnace (SRF) depending on temperature and composition. In this study, a 270 kVA DC electric arc furnace were used to determine the electrical characteristic of molten ancient copper slags. The specific conductivity of the slag was estimated by using furnace geometric factor given in the literature as an empirical formula and by using furnace resistance measured during smelting of the copper slag with or without different additives such as coke, CaO and Al 2 O 3 . (Original)

  19. 1982 Australian coal conference papers

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    This third Australian coal conference included papers discussing the market for coal, finance and investment, use of computers, mining, coal research, coal preparation and waste disposal, marketing and trade, and the transport of coal. All papers have been individually abstracted.

  20. Development of a Coal Quality Expert

    Energy Technology Data Exchange (ETDEWEB)

    None

    1998-06-20

    ABB Power Plant Laboratories Combustion Engineering, Inc., (ABB CE) and CQ Inc. completed a broad, comprehensive program to demonstrate the economic and environmental benefits of using higher quality U.S. coals for electrical power generation and developed state-of-the-art user-friendly software--Coal Quality Expert (CQE)-to reliably predict/estimate these benefits in a consistent manner. The program was an essential extension and integration of R and D projects performed in the past under U.S. DOE and EPRI sponsorship and it expanded the available database of coal quality and power plant performance information. This software will permit utilities to purchase the lowest cost clean coals tailored to their specific requirements. Based on common interest and mutual benefit, the subject program was cosponsored by the U.S. DOE, EPRI, and eight U.S. coal-burning utilities. In addition to cosponsoring this program, EPN contributed its background research, data, and computer models, and managed some other supporting contracts under the terms of a project agreement established between CQ Inc. and EPRI. The essential work of the proposed project was performed under separate contracts to CQ Inc. by Electric Power Technologies (El?'T), Black and Veatch (B and V), ABB Combustion Engineering, Babcock and Wilcox (B and W), and Decision Focus, Inc. Although a significant quantity of the coals tied in the United States are now cleaned to some degree before firing, for many of these coals the residual sulfur content requires users to install expensive sulfur removal systems and the residual ash causes boilers to operate inefficiently and to require frequent maintenance. Disposal of the large quantities of slag and ash at utility plant sites can also be problematic and expensive. Improved and advanced coal cleaning processes can reduce the sulfur content of many coals to levels conforming to environmental standards without requiring post-combustion desulfurization systems. Also

  1. Enhanced Combustion Low NOx Pulverized Coal Burner

    Energy Technology Data Exchange (ETDEWEB)

    David Towle; Richard Donais; Todd Hellewell; Robert Lewis; Robert Schrecengost

    2007-06-30

    economic evaluation and commercial application. During the project performance period, Alstom performed computational fluid dynamics (CFD) modeling and large pilot scale combustion testing in its Industrial Scale Burner Facility (ISBF) at its U.S. Power Plant Laboratories facility in Windsor, Connecticut in support of these objectives. The NOx reduction approach was to optimize near-field combustion to ensure that minimum NOx emissions are achieved with minimal impact on unburned carbon in ash, slagging and fouling, corrosion, and flame stability/turn-down. Several iterations of CFD and combustion testing on a Midwest coal led to an optimized design, which was extensively combustion tested on a range of coals. The data from these tests were then used to validate system costs and benefits versus SCR. Three coals were evaluated during the bench-scale and large pilot-scale testing tasks. The three coals ranged from a very reactive subbituminous coal to a moderately reactive Western bituminous coal to a much less reactive Midwest bituminous coal. Bench-scale testing was comprised of standard ASTM properties evaluation, plus more detailed characterization of fuel properties through drop tube furnace testing and thermogravimetric analysis. Bench-scale characterization of the three test coals showed that both NOx emissions and combustion performance are a strong function of coal properties. The more reactive coals evolved more of their fuel bound nitrogen in the substoichiometric main burner zone than less reactive coal, resulting in the potential for lower NOx emissions. From a combustion point of view, the more reactive coals also showed lower carbon in ash and CO values than the less reactive coal at any given main burner zone stoichiometry. According to bench-scale results, the subbituminous coal was found to be the most amenable to both low NOx, and acceptably low combustibles in the flue gas, in an air staged low NOx system. The Midwest bituminous coal, by contrast, was

  2. Low-rank coal research, Task 5.1. Topical report, April 1986--December 1992

    Energy Technology Data Exchange (ETDEWEB)

    1993-02-01

    This document is a topical progress report for Low-Rank Coal Research performed April 1986 - December 1992. Control Technology and Coal Preparation Research is described for Flue Gas Cleanup, Waste Management, Regional Energy Policy Program for the Northern Great Plains, and Hot-Gas Cleanup. Advanced Research and Technology Development was conducted on Turbine Combustion Phenomena, Combustion Inorganic Transformation (two sections), Liquefaction Reactivity of Low-Rank Coals, Gasification Ash and Slag Characterization, and Coal Science. Combustion Research is described for Atmospheric Fluidized-Bed Combustion, Beneficiation of Low-Rank Coals, Combustion Characterization of Low-Rank Fuels (completed 10/31/90), Diesel Utilization of Low-Rank Coals (completed 12/31/90), Produce and Characterize HWD (hot-water drying) Fuels for Heat Engine Applications (completed 10/31/90), Nitrous Oxide Emission, and Pressurized Fluidized-Bed Combustion. Liquefaction Research in Low-Rank Coal Direct Liquefaction is discussed. Gasification Research was conducted in Production of Hydrogen and By-Products from Coals and in Sulfur Forms in Coal.

  3. Destructive distillation of coals

    Energy Technology Data Exchange (ETDEWEB)

    Rollason, A

    1918-08-23

    To obtain light oils and ammonia from coals having volatile and oxygen contents, the crushed material is mixed with 5 percent of ground amorphous calcium carbonate and distilled slowly in a cast iron retort to remove the water and light oils, the ammonia being synthesized at a later stage. The crushed residue is gasified in a producer by a blast of air and superheated steam at about 950/sup 0/C. The steam and air are passed very slowly at low pressure through the fuel to cause the dissociation of the atmospheric nitrogen molecules into atoms. The gases are then passed to a heater, having a temperature of 500/sup 0/C, and thence to a continuously working externally-heated retort charged with fuel, such as the hard retort residues, maintained below 850/sup 0/C. The water vapor in the gases is dissociated by the incandescent fuel, the oxygen combining with the carbon, and the lime present in the fuel causes the hydrogen to combine with the free nitrogen atoms, thus forming ammonia. The gases after leaving the retort are cooled down to 85 to 95/sup 0/C and the ammonia may be recovered by conversion into ammonium sulphate. The resultant cooled gases may again be charged with superheated steam and utilized again in the heater and retort.

  4. Ultravitrinite coals from Chukotka

    Energy Technology Data Exchange (ETDEWEB)

    Lapo, A.V.; Letushova, I.A.

    1979-03-01

    Chemical and petrographic analysis was conducted on coals from the Anadyrya and Bukhti Ugol'noi deposits. Characteristics of the most prevalent type of vitrinite coals in both regions are presented here. Anadyrya coals belong to a transitional phase between brown coal and long flame. Ultravitrinite coals predominate. Gas coals from Bukti Ugol'noi have a higher carbon content than Anadyrya coals. They also have a higher hydrogen content and yield of initial resin. In several cases there was also a higher yield of volatile substances. Chukotka coals are characterized by a 10 percent higher initial resin yield than equally coalified Donetsk coals, other indicators were equal to those of Donetsk coals. Because of this, Chukotka coals are suitable for fuel in power plants and as raw materials in the chemical industry. (15 refs.) (In Russian)

  5. Integrating multi-objective optimization with computational fluid dynamics to optimize boiler combustion process of a coal fired power plant

    International Nuclear Information System (INIS)

    Liu, Xingrang; Bansal, R.C.

    2014-01-01

    Highlights: • A coal fired power plant boiler combustion process model based on real data. • We propose multi-objective optimization with CFD to optimize boiler combustion. • The proposed method uses software CORBA C++ and ANSYS Fluent 14.5 with AI. • It optimizes heat flux transfers and maintains temperature to avoid ash melt. - Abstract: The dominant role of electricity generation and environment consideration have placed strong requirements on coal fired power plants, requiring them to improve boiler combustion efficiency and decrease carbon emission. Although neural network based optimization strategies are often applied to improve the coal fired power plant boiler efficiency, they are limited by some combustion related problems such as slagging. Slagging can seriously influence heat transfer rate and decrease the boiler efficiency. In addition, it is difficult to measure slag build-up. The lack of measurement for slagging can restrict conventional neural network based coal fired boiler optimization, because no data can be used to train the neural network. This paper proposes a novel method of integrating non-dominated sorting genetic algorithm (NSGA II) based multi-objective optimization with computational fluid dynamics (CFD) to decrease or even avoid slagging inside a coal fired boiler furnace and improve boiler combustion efficiency. Compared with conventional neural network based boiler optimization methods, the method developed in the work can control and optimize the fields of flue gas properties such as temperature field inside a boiler by adjusting the temperature and velocity of primary and secondary air in coal fired power plant boiler control systems. The temperature in the vicinity of water wall tubes of a boiler can be maintained within the ash melting temperature limit. The incoming ash particles cannot melt and bond to surface of heat transfer equipment of a boiler. So the trend of slagging inside furnace is controlled. Furthermore, the

  6. Concrete with steel furnace slag and fractionated reclaimed asphalt pavement.

    Science.gov (United States)

    2014-09-01

    Steel furnace slag (SFS) is an industrial by-product material that can contain free calcium oxide (CaO) and free magnesium oxide (MgO), both : of which can cause significant expansion when hydrated. SFS aggregates are therefore not commonly used in c...

  7. Design and evaluation of a heat recuperator for steel slags

    International Nuclear Information System (INIS)

    Gutiérrez Trashorras, Antonio J.; Álvarez, Eduardo Álvarez; Río González, José Luis; Suarez Cuesta, José Manuel; Bernat, Jorge Xiberta

    2013-01-01

    New techniques for emissions reduction and energy efficiency are important challenges of the steel industry. Although great advantages have been reached in these fields, there are still new opportunities. One of them is the possible development of systems to recover energy from slags. The recent policies that encourage the use of renewable and alternative energies determine a favorable scenario for the development of new techniques of heat recovering. In this context, this article presents a new heat recuperation system for the slags produced in the factories of Arcelor–Mittal in Asturias (Spain) and study in detail the design of an innovative slags heat exchanger. To adjust its performance and to determine the influence of the geometric and flow design parameters, the heat exchanger has been simulated using numerical analysis software (CFD). -- Highlights: • A new design of a heat recuperator for slags energy recovery is presented. • The effects of the design parameters have been studied with a numerical model. • Refractory materials with high thermal conductivity improve heat recuperation

  8. Environmental and economic implications of slag disposal practices ...

    African Journals Online (AJOL)

    2003-01-01

    Jan 1, 2003 ... pollution prevention, control or remediation measures. ... Total elimination of the production of slag is impossible at this stage ... issues, for example, relevant usage of the two different methods for classification and ascribing a higher ...... LIDE DR (1994) CRC Handbook of Chemistry and Physics(75th edn.) ...

  9. Utilization of steel slag for Portland cement clinker production.

    Science.gov (United States)

    Tsakiridis, P E; Papadimitriou, G D; Tsivilis, S; Koroneos, C

    2008-04-01

    The aim of the present research work is to investigate the possibility of adding steel slag, a by-product of the conversion of iron to steel process, in the raw meal for the production of Portland cement clinker. Two samples of raw meals were prepared, one with ordinary raw materials, as a reference sample ((PC)(Ref)), and another with 10.5% steel slag ((PC)(S/S)). Both raw meals were sintered at 1450 degrees C. The results of chemical and mineralogical analyses as well as the microscopic examination showed that the use of the steel slag did not affect the mineralogical characteristics of the so produced Portland cement clinker. Furthermore, both clinkers were tested by determining the grindability, setting times, compressive strengths and soundness. The hydration products were examined by XRD analysis at 2, 7, 28 and 90 days. The results of the physico-mechanical tests showed that the addition of the steel slag did not negatively affect the quality of the produced cement.

  10. Granulated blast furnace slag – A boon for foundry industry

    African Journals Online (AJOL)

    Keywords: Silica sand; Blast Furnace Slag; Mould properties; Ferrous and nonferrous ... raw material for the production of cast components in foundry industries. ... applications for conserving natural resources and reduce the cost of the raw .... in an elevated temperature melting furnace with temperature values of 750 to.

  11. The Interfacial Transition Zone in Alkali-Activated Slag Mortars

    Directory of Open Access Journals (Sweden)

    Rackel eSan Nicolas

    2015-12-01

    Full Text Available The interfacial transition zone (ITZ is known to strongly influence the mechanical and transport properties of mortars and concretes. This paper studies the ITZ between siliceous (quartz aggregates and alkali activated slag binders in the context of mortar specimens. Backscattered electron images (BSE generated in an environmental scanning electron microscope (ESEM are used to identify unreacted binder components, reaction products and porosity in the zone surrounding aggregate particles, by composition and density contrast. X-ray mapping is used to exclude the regions corresponding to the aggregates from the BSE image of the ITZ, thus enabling analysis of only the binder phases, which are segmented into binary images by grey level discrimination. A distinct yet dense ITZ region is present in the alkali-activated slag mortars, containing a reduced content of unreacted slag particles compared to the bulk binder. The elemental analysis of this region shows that it contains a (C,N-A-S-H gel which seems to have a higher content of Na (potentially deposited through desiccation of the pore solution and a lower content of Ca than the bulk inner and outer products forming in the main binding region. These differences are potentially important in terms of long-term concrete performance, as the absence of a highly porous interfacial transition zone region is expected to provide a positive influence on the mechanical and transport properties of alkali-activated slag concretes.

  12. Copper recovery from slag by indirect bio leaching

    International Nuclear Information System (INIS)

    Mazuelos, A.; Iglesias, N.; Romero, R.; Forcat, O.; Carranza, F.

    2009-01-01

    The main source of copper loss from a smelter is copper in discard slag. Slag can contain Cu in concentrations very much higher than those of many ores. Cu is present in slag entrained in very small drops of matte, white metal and blister copper occluded in fayalitic phase. In this work, the technical viability of the BRISA process, that is based on the indirect bio leaching, for this residue has been proved. A sample of slag, containing 2 % of copper, has been chemical, granulometric and metallographic characterized and it has been leached with ferric sulphate solutions in agitated reactors. The influence of several variables have been investigated. Once the best operating conditions had been selecting and an economic estimation had been done (with very really attractive results), the leaching stage has been designed for a plant of 30 tonnes per hour capacity. Cu extractions higher than 70% can be achieved with a residence time of only five hours. Despite of Cu(II) concentration in fed is as high as 30 g/l, bio oxidation stage can supply Fe(III) demanded by ferric leaching stage. (Author) 17 refs

  13. Application of aluminum slag incorporated in lightweigh aggregate

    International Nuclear Information System (INIS)

    Takahashi, Elisa Akiko Nakano

    2006-01-01

    The use of industrial waste materials as additives in the manufacture of ceramic product has been attracting a growing interest in the last few years and is becoming common practice. The main purpose of this work is to evaluate the possibility of incorporation of aluminum slag into clay materials. Expansive clays are obtained from a pyro plastic expansion, and are usually employed like lightweight aggregate in structural concrete as ornamental garden products. The characterization of the aluminum slag and clay materials was carried out by Xray fluorescence spectrometry, Xray diffraction, granulometry, differential thermal analysis, thermal gravimetry (DTA and TG) and scanning electron microscopy. The studied compositions contained 5, 10, 15 and 20 weight % of aluminum slag into clay mass. The linear expansion, mass variation, apparent specific mass and water absorption of all compositions were determined. Leaching and solubilization experiments were also performed. The main results show the viability of using up to 5 wt% aluminum slag for producing expansive clays with characteristics within the accepted standards. (author)

  14. Aan de slag met honors : praktijklessen uit Europa

    NARCIS (Netherlands)

    Wolfensberger, Marca; Hogenstijn, Maarten

    2015-01-01

    In de brochure ‘Aan de slag met honors’ worden onderzoeksresultaten van het onderzoeksproject Honors in Europe hertaald naar tips voor succesvol en inspirerend honorsonderwijs. De brochure is grotendeels gebaseerd op het boek Talent Development in European Higher Education – Honors programs in the

  15. Chemical characterization and local dispersion of slag generated by ...

    African Journals Online (AJOL)

    SAM

    2014-05-07

    May 7, 2014 ... Pb from acid batteries includes their rupture, draining of the acid, separation of the components containing Pb and its recovery by smelting (Faé et al., 2011). During the smelting process, a solid material called "slag" is generated. It contains a high concentration of Pb, among other toxic elements (Coya et al.

  16. Kinetics of steel slag leaching: Batch tests and modeling

    International Nuclear Information System (INIS)

    De Windt, Laurent; Chaurand, Perrine; Rose, Jerome

    2011-01-01

    Reusing steel slag as an aggregate for road construction requires to characterize the leaching kinetics and metal releases. In this study, basic oxygen furnace (BOF) steel slag were subjected to batch leaching tests at liquid to solid ratios (L/S) of 10 and 100 over 30 days; the leachate chemistry being regularly sampled in time. A geochemical model of the steel slag is developed and validated from experimental data, particularly the evolution with leaching of mineralogical composition of the slag and trace element speciation. Kinetics is necessary for modeling the primary phase leaching, whereas a simple thermodynamic equilibrium approach can be used for secondary phase precipitation. The proposed model simulates the kinetically-controlled dissolution (hydrolysis) of primary phases, the precipitation of secondary phases (C-S-H, hydroxide and spinel), the pH and redox conditions, and the progressive release of major elements as well as the metals Cr and V. Modeling indicates that the dilution effect of the L/S ratio is often coupled to solubility-controlled processes, which are sensitive to both the pH and the redox potential. A sensitivity analysis of kinetic uncertainties on the modeling of element releases is performed.

  17. Characteristics of carbonized sludge for co-combustion in pulverized coal power plants.

    Science.gov (United States)

    Park, Sang-Woo; Jang, Cheol-Hyeon

    2011-03-01

    Co-combustion of sewage sludge can destabilize its combustion profile due to high volatility, which results in unstable flame. We carried out fuel reforming for sewage sludge by way of carbonization at pyrolysis temperature of 300-500°C. Fuel characteristics of carbonized sludge at each temperature were analyzed. As carbonization temperature increased, fuel ratio increased, volatile content reduced, and atomic ratio relation of H/C and O/C was similar to that of lignite. The analysis result of FT-IR showed the decrease of aliphatic C-H bond and O-C bond in carbonization. In the analysis result of TG-DTG, the thermogravimetry reduction temperature of carbonized sludge (CS400) was proven to be higher than that of dried sludge, but lower than that of sub-bituminous coal. Hardgrove grindability index increased in proportion to fuel ratio increase, where the carbonized sludge value of 43-110 was similar or higher than the coal value of 49-63. As for ash deposits, slagging and fouling index were higher than that of coal. When carbonized sludge (CS400) and coal were co-combusted in 1-10% according to calorific value, slagging tendency was low in all conditions, and fouling tendency was medium or high according to the compositions of coal. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Characteristics of carbonized sludge for co-combustion in pulverized coal power plants

    International Nuclear Information System (INIS)

    Park, Sang-Woo; Jang, Cheol-Hyeon

    2011-01-01

    Co-combustion of sewage sludge can destabilize its combustion profile due to high volatility, which results in unstable flame. We carried out fuel reforming for sewage sludge by way of carbonization at pyrolysis temperature of 300-500 deg. C. Fuel characteristics of carbonized sludge at each temperature were analyzed. As carbonization temperature increased, fuel ratio increased, volatile content reduced, and atomic ratio relation of H/C and O/C was similar to that of lignite. The analysis result of FT-IR showed the decrease of aliphatic C-H bond and O-C bond in carbonization. In the analysis result of TG-DTG, the thermogravimetry reduction temperature of carbonized sludge (CS400) was proven to be higher than that of dried sludge, but lower than that of sub-bituminous coal. Hardgrove grindability index increased in proportion to fuel ratio increase, where the carbonized sludge value of 43-110 was similar or higher than the coal value of 49-63. As for ash deposits, slagging and fouling index were higher than that of coal. When carbonized sludge (CS400) and coal were co-combusted in 1-10% according to calorific value, slagging tendency was low in all conditions, and fouling tendency was medium or high according to the compositions of coal.

  19. Coal Tar and Coal-Tar Pitch

    Science.gov (United States)

    Learn about coal-tar products, which can raise your risk of skin cancer, lung cancer, and other types of cancer. Examples of coal-tar products include creosote, coal-tar pitch, and certain preparations used to treat skin conditions such as eczema, psoriasis, and dandruff.

  20. Cooling towers

    International Nuclear Information System (INIS)

    Korik, L.; Burger, R.

    1992-01-01

    What is the effect of 0.6C (1F) temperature rise across turbines, compressors, or evaporators? Enthalpy charts indicate for every 0.6C (1F) hotter water off the cooling tower will require an additional 2 1/2% more energy cost. Therefore, running 2.2C (4F) warmer due to substandard cooling towers could result in a 10% penalty for overcoming high heads and temperatures. If it costs $1,250,000.00 a year to operate the system, $125,000.00 is the energy penalty for hotter water. This paper investigates extra fuel costs involved in maintaining design electric production with cooling water 0.6C (1F) to 3C (5.5F) hotter than design. If design KWH cannot be maintained, paper will calculate dollar loss of saleable electricity. The presentation will conclude with examining the main causes of deficient cold water production. State-of-the-art upgrading and methodology available to retrofit existing cooling towers to optimize lower cooling water temperatures will be discussed

  1. On-stream analysis of coal by prompt neutron activation analysis

    International Nuclear Information System (INIS)

    Barker, D.

    1981-01-01

    The need for rapid continuous on-stream analysis of coal was recognised in 1975. Analytical systems capable of determining some of the most important compositional properties of coal have been developed. The research programme has produced a series of analysers suitable for on-stream, batch, slurry and laboratory analytical determination of coal. This series of analysers is marketed under the name of 'Nucoalyzer'. The Nucoalyzer - CONAC (Continuous On-line Nuclear Analyzer for Coal) offers real-time, continuous determination of calorific value, percentage ash, percentage moisture, percentage sulphur, boiler fouling and slagging indices. The CONAC model is described in this article. The analytical principle employed in the various Nucoalyzer systems is based on prompt neutron activation analysis

  2. Hydrology and geochemistry of a slag-affected aquifer and chemical characteristics of slag-affected ground water, northwestern Indiana and northeastern Illinois

    Science.gov (United States)

    Bayless, E. Randall; Greeman, T.K.; Harvey, C.C.

    1998-01-01

    Slag is a by-product of steel manufacturing and a ubiquitous fill material in northwestern Indiana. Ground water associated with slag deposits generally is characterized by high pH and elevated concentrations of many inorganic water-quality constituents. The U.S. Geological Survey, in cooperation with the Indiana Department of Environmental Management, conducted a study in northwestern Indiana from June 1995 to September 1996 to improve understanding of the effects of slag deposits on the water quality of a glacial-outwash aquifer. The Bairstow Landfill, a slag-fill deposit overlying the Calumet aquifer near Hammond, Indiana, was studied to represent conditions in slag-deposit settings that are common in northwestern Indiana. Ground water from 10 observation wells, located in four nests at the site, and surface water from the adjacent Lake George were analyzed for values of field-measured parameters and concentrations of major ions, nutrients, trace elements, and bulk properties. Solid-phase samples of slag and aquifer sediment collected during drilling were examined with X-ray diffraction and geochemical digestion and analysis. Concentrations of calcium, potassium, sodium, and sulfate were highest in wells screened partly or fully in slag. Potassium concentrations in ground water ranged from 2.9 to 120 milligrams per liter (mg/L), were highest in water from slag deposits, and decreased with depth. The highest concentrations for aluminum, barium, molybdenum, nickel, and selenium were in water from the slag. Silica concentrations were highest in wells screened directly beneath the slag?aquifer interface, and magnesium concentrations were highest in intermediate and deep aquifer wells. Silica concentrations in shallow and intermediate aquifer wells ranged from 27 to 41 mg/L and were about 10 times greater than those in water from slag deposits. The highest concentrations for chromium, lead, and zinc were in ground water from immediately below the slag

  3. Cold experiments on ligament formation for blast furnace slag granulation

    International Nuclear Information System (INIS)

    Liu Junxiang; Yu Qingbo; Li Peng; Du Wenya

    2012-01-01

    Rotary cup atomization for molten slag granulation is an attractive alternative to water quenching. However, the mechanism of disintegration of molten slag must be assessed. In the present study, a glycerol/water mixture was substituted for molten slag, and the mechanism of ligament formation in a rotary cup was investigated using photos taken by a high-speed camera. The effects of the angular speed and inner depth of the rotary cup on ligament disintegration was investigated. The results showed that one state of disintegration may transform into another state as the angular speed of the rotary cup increases at a given liquid flow rate. During ligament formation, the number of ligaments increased with an increase in the angular speed of the rotary cup, and a decrease in the diameter of ligament and liquid drop was observed. Moreover, the initial point of disintegration of the ligament moved to the lip of the rotary cup as the angular speed increased. An equation describing the relationship between the diameter of the liquid drop and various factors was used to predict the diameter of the liquid drop. A rotary cup with an inner depth of 30 mm was the best choice for granulation. The results of the present study will be useful for designing devices used in molten slag granulation. - Highlights: ►The results can be used in the granulation of molten blast furnace slag. ► The three different states of disintegration occur as the angular speed of rotary cup increases. ► The mechanism of ligament disintegration is analyzed. ► Eq. can be used to predict the diameter of liquid drop. ► A rotary cup with an inner depth of 30 mm is optimal for granulation.

  4. Conditions for testing the corrosion rates of ceramics in coal gasification systems

    Energy Technology Data Exchange (ETDEWEB)

    Hurley, J.P.; Nowok, J.W. [Univ. of North Dakota, Grand Forks, ND (United States)

    1996-08-01

    Coal gasifier operating conditions and gas and ash compositions affect the corrosion rates of ceramics used for construction in three ways: (1) through direct corrosion of the materials, (2) by affecting the concentration and chemical form of the primary corrodents, and (3) by affecting the mass transport rate of the primary corrodents. To perform an accurate corrosion test on a system material, the researcher must include all relevant corrodents and simulate conditions in the gasifier as closely as possible. In this paper, the authors present suggestions for conditions to be used in such corrosion tests. Two main types of corrosion conditions are discussed: those existing in hot-gas cleanup systems where vapor and dry ash may contribute to corrosion and those experienced by high-temperature heat exchangers and refractories where the main corrodent will be coal ash slag. Only the fluidized-bed gasification systems such as the Sierra Pacific Power Company Pinon Pine Power Project system are proposing the use of ceramic filters for particulate cleanup. The gasifier is an air-blown 102-MWe unit employing a Westinghouse{trademark} ceramic particle filter system operating at as high as 1100{degrees}F at 300 psia. Expected gas compositions in the filter will be approximately 25% CO, 15% H{sub 2}, 5% CO{sub 2}, 5% H{sub 2}O, and 50% N{sub 2}. Vapor-phase sodium chloride concentrations are expected to be 10 to 100 times the levels in combustion systems at similar temperatures, but in general the concentrations of the minor primary and secondary corrodents are not well understood. Slag corrosiveness will depend on its composition as well as viscosity. For a laboratory test, the slag must be in a thermodynamically stable form before the beginning of the corrosion test to assure that no inappropriate reactions are allowed to occur. Ideally, the slag would be flowing, and the appropriate atmosphere must be used to assure realistic slag viscosity.

  5. CATALYTIC GASIFICATION OF COAL USING EUTECTIC SALT MIXTURES; FINAL

    International Nuclear Information System (INIS)

    Dr. Yaw D. Yeboah; Dr. Yong Xu; Dr. Atul Sheth; Dr. Pradeep Agrawal

    2001-01-01

    The Gas Research Institute (GRI) estimates that by the year 2010, 40% or more of U.S. gas supply will be provided by supplements including substitute natural gas (SNG) from coal. These supplements must be cost competitive with other energy sources. The first generation technologies for coal gasification e.g. the Lurgi Pressure Gasification Process and the relatively newer technologies e.g. the KBW (Westinghouse) Ash Agglomerating Fluidized-Bed, U-Gas Ash Agglomerating Fluidized-Bed, British Gas Corporation/Lurgi Slagging Gasifier, Texaco Moving-Bed Gasifier, and Dow and Shell Gasification Processes, have several disadvantages. These disadvantages include high severities of gasification conditions, low methane production, high oxygen consumption, inability to handle caking coals, and unattractive economics. Another problem encountered in catalytic coal gasification is deactivation of hydroxide forms of alkali and alkaline earth metal catalysts by oxides of carbon (CO(sub x)). To seek solutions to these problems, a team consisting of Clark Atlanta University (CAU, a Historically Black College and University, HBCU), the University of Tennessee Space Institute (UTSI) and Georgia Institute of Technology (Georgia Tech) proposed to identify suitable low melting eutectic salt mixtures for improved coal gasification. The research objectives of this project were to: Identify appropriate eutectic salt mixture catalysts for coal gasification; Assess agglomeration tendency of catalyzed coal; Evaluate various catalyst impregnation techniques to improve initial catalyst dispersion; Determine catalyst dispersion at high carbon conversion levels; Evaluate effects of major process variables (such as temperature, system pressure, etc.) on coal gasification; Evaluate the recovery, regeneration and recycle of the spent catalysts; and Conduct an analysis and modeling of the gasification process to provide better understanding of the fundamental mechanisms and kinetics of the process

  6. CATALYTIC GASIFICATION OF COAL USING EUTECTIC SALT MIXTURES

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Yaw D. Yeboah; Dr. Yong Xu; Dr. Atul Sheth; Dr. Pradeep Agrawal

    2001-12-01

    The Gas Research Institute (GRI) estimates that by the year 2010, 40% or more of U.S. gas supply will be provided by supplements including substitute natural gas (SNG) from coal. These supplements must be cost competitive with other energy sources. The first generation technologies for coal gasification e.g. the Lurgi Pressure Gasification Process and the relatively newer technologies e.g. the KBW (Westinghouse) Ash Agglomerating Fluidized-Bed, U-Gas Ash Agglomerating Fluidized-Bed, British Gas Corporation/Lurgi Slagging Gasifier, Texaco Moving-Bed Gasifier, and Dow and Shell Gasification Processes, have several disadvantages. These disadvantages include high severities of gasification conditions, low methane production, high oxygen consumption, inability to handle caking coals, and unattractive economics. Another problem encountered in catalytic coal gasification is deactivation of hydroxide forms of alkali and alkaline earth metal catalysts by oxides of carbon (CO{sub x}). To seek solutions to these problems, a team consisting of Clark Atlanta University (CAU, a Historically Black College and University, HBCU), the University of Tennessee Space Institute (UTSI) and Georgia Institute of Technology (Georgia Tech) proposed to identify suitable low melting eutectic salt mixtures for improved coal gasification. The research objectives of this project were to: Identify appropriate eutectic salt mixture catalysts for coal gasification; Assess agglomeration tendency of catalyzed coal; Evaluate various catalyst impregnation techniques to improve initial catalyst dispersion; Determine catalyst dispersion at high carbon conversion levels; Evaluate effects of major process variables (such as temperature, system pressure, etc.) on coal gasification; Evaluate the recovery, regeneration and recycle of the spent catalysts; and Conduct an analysis and modeling of the gasification process to provide better understanding of the fundamental mechanisms and kinetics of the process.

  7. Cooling tower

    Energy Technology Data Exchange (ETDEWEB)

    Norbaeck, P; Heneby, H

    1976-01-22

    Cooling towers to be transported on road vehicles as a unit are not allowed to exceed certain dimensions. In order to improve the efficiency of such a cooling tower (of cross-flow design and box-type body) with given dimensions, it is proposed to arrange at least one of the scrubbing bodies displaceable within a module or box. Then it can be moved out of the casing into working position, thereby increasing the front surface available for the inlet of air (and with it the efficiency) by nearly a factor of two.

  8. Record coking coal settlements

    Energy Technology Data Exchange (ETDEWEB)

    Macdonald, C.

    2005-02-01

    The US$100/tonne psychological barrier in coking coal prices has been well and truly smashed. The article examines developments in coal pricing. It includes quotes from many senior executives in the coal industry as collected at McCloskey's Australian Coal.04 conference held in Sydney, 18-19 November 2004. 2 photos.

  9. COAL Conference Poster

    OpenAIRE

    Brown, Taylor Alexander; McGibbney, Lewis John

    2017-01-01

    COAL Conference Poster This archive contains the COAL conference poster for the AGU Fall Meeting 2017 by Taylor Alexander Brown. The Inkscape SVG source is available at https://github.com/capstone-coal/coal-conference-poster/ under the Creative Commons Attribution-ShareAlike 4.0 International license.

  10. Use of new ceramic linings in coal preparation plants

    Energy Technology Data Exchange (ETDEWEB)

    Fedorchenko, V.E.; Rudenko, V.A.; Bondarev, A.Ya.

    1984-01-01

    This article evaluates several materials used as liners in coal preparation equipment. The evaluations concentrate on liners used under conditions of intensive temperature fluctuations, e.g. liners of coal chutes for coal transport from coal dryers. Two aspects of wear are analyzed: abrasion by friction and effects of temperature fluctuations. Abrasive wear is tested using magnetite suspension with a density of 400 g/l. Tests show that abrasive wear of liners on an alumina basis is 3 times lower than abrasive wear of high quality steel, from 13 to 24 times lower than that of iron and from 6 to 8 times lower than that of steels used in coal preparation plants. Effects of temperature fluctuations from 20 to 840 C on abrasive wear of liners of steels, iron, slag glass ceramics, mullite-corundum material and corundum is shown in a table. The test show that mullite-corundum material on the basis of alumina is characterized by a high resistance to abrasive wear after 30 cycles of temperature increase from 20 to 840 C and decrease to 20 C. Using mullite-corundum as liners of equipment and installations operating under conditions of temperature fluctuations is recommended.

  11. Coal option. [Shell Co

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    This paper notes the necessity of developing an international coal trade on a very large scale. The role of Shell in the coal industry is examined; the regions in which Shell companies are most active are Australia, Southern Africa, Indonesia; Europe and North America. Research is being carried out on marketing and transportation, especially via slurry pipelines; coal-oil emulsions; briquets; fluidized-bed combustion; recovery of coal from potential waste material; upgrading of low-rank coals; unconventional forms of mining; coal conversion (the Shell/Koppers high-pressure coal gasification process). Techniques for cleaning flue gas (the Shell Flue Gas Desulfurization process) are being examined.

  12. Concerning coal: an anthology

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, M.; Hawse, M.L.; Maloney, P.J. [eds.

    1997-12-31

    The anthology takes a humanistic look at coal mining in Illinois. One of its goals is to increase public awareness of coal in American society; it also seeks to enhance understanding of the historical aspects of coal and to study the impact of coal on mining families. Many of the 25 selections in the anthology come from Coal Research Center publications, `Concerning coal` and `Mineral matters`. Articles are arranged in three parts entitled: life in the mining community; mining in folklore, story telling, literature, art and music; and technology as it affected the people of the coal fields. 117 refs., 25 photos. 1 map.

  13. Coal information 1995

    International Nuclear Information System (INIS)

    1996-01-01

    This volume is a comprehensive reference book on current world coal market trends and long-term prospects to 2010. It contains an in-depth analysis of the 1995 international coal market covering prices, demand, trade, supply and production capacity as well as over 450 pages of country specific statistics on OECD and key non-OECD coal producing and consuming countries. The book also includes a summary of environmental policies on climate change and on coal-related air quality issues as well as essential facts on coal-fired power stations in coal-importing regions, on coal ports world-wide and on emission standards for coal-fired boilers in OECD countries. Coal Information is one of a series of annual IEA statistical publications on major energy sources; other reports are Oil and Gas Information and Electricity Information. Coal Information 1995 is published in July 1996. (author)

  14. Coal yearbook 1993

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    This book is the first coal yearbook published by ATIC (France). In a first chapter, economical context of coal worldwide market is analyzed: comparative evaluations on coal exports and imports, coal industry, prices, production in USA, Australia, South Africa, China, former USSR, Poland, Colombia, Venezuela and Indonesia are given. The second chapter describes the french energy context: national coal production, imports, sectorial analysis, maritime transport. The third chapter describes briefly the technologies of clean coal and energy saving developed by Charbonnages de France: fossil-fuel power plants with combined cycles and cogeneration, fluidized beds for the recovery of coal residues, recycling of agricultural wastes (sugar cane wastes) in thermal power plant, coal desulfurization for air pollution abatement. In the last chapter, statistical data on coal, natural gas and crude oil are offered: world production, world imports, world exports, french imports, deliveries to France, coal balance, french consumption of primary energy, power generation by fuel type

  15. A novel comprehensive utilization of vanadium slag: As gamma ray shielding material

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Mengge [School of Metallurgy, Northeastern University, Shenyang 110004 (China); Liaoning Key Laboratory of Metallurgical Resources Recycling Science, Shenyang 110004 (China); Xue, Xiangxin, E-mail: xuexx@mail.neu.edu.cn [School of Metallurgy, Northeastern University, Shenyang 110004 (China); Liaoning Key Laboratory of Metallurgical Resources Recycling Science, Shenyang 110004 (China); Yang, He; Liu, Dong [School of Metallurgy, Northeastern University, Shenyang 110004 (China); Liaoning Key Laboratory of Metallurgical Resources Recycling Science, Shenyang 110004 (China); Wang, Chao [Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Li, Zhefu [Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2016-11-15

    Highlights: • A novel comprehensive utilization method for vanadium slag is proposed. • Shielding properties of vanadium slag are better than ordinary concrete. • HVL of vanadium slag is between Lead and concrete to shield {sup 60}Co gamma ray. • HVL of composite is higher than concrete when adding amount of vanadium slag is 900. • Composite can be used as injecting mortar for cracks developed in concrete shields. - Abstract: New exploration of vanadium slag as gamma ray shielding material was proposed, the shielding properties of vanadium slag was higher than concrete when the energy of photons was in 0.0001 MeV–100000 MeV. Vanadium slag/epoxy resin composites were prepared, shielding and material properties of materials were tested by {sup 60}Co gamma ray, simultaneous DSC-TGA, electronic universal testing machine and scanning electron microscopy, respectively. The results showed that the shielding properties of composite would be better with the increase of vanadium slag addition amount. The HVL (half value layer thickness) of vanadium slag was between Lead and concrete while composite was higher than concrete when the addition amount of vanadium slag was 900 used as material to shield {sup 60}Co gamma ray, also the resistance temperature of composite was about 215 °C and the bending strength was over 10 MPa. The composites could be used as injecting mortar for cracks developed in biological concrete shields, coating for the floor of the nuclear facilities, and shielding materials by itself.

  16. Corrosion Behavior of Ceramic Cup of Blast Furnace Hearth by Liquid Iron and Slag

    Science.gov (United States)

    Li, Yanglong; Cheng, Shusen; Wang, Zhifeng

    2016-10-01

    Three kinds of sample bricks of ceramic cups for blast furnace hearth were studied by dynamic corrosion tests based on different corrosion systems, i.e., liquid iron system, liquid slag system and liquid iron-slag system. Considering the influence of temperature and sample rotational speed, the corrosion profiles and mass loss of the samples were analyzed. In addition, the microstructure of the corroded samples was observed by optical microscope (OM) and scanning electron microscope (SEM). It was found that the corrosion profiles could be divided into iron corrosion region, slag corrosion region and iron-slag corrosion region via corrosion degree after iron-slag corrosion experiment. The most serious corrosion occurred in iron-slag corrosion region. This is due to Marangoni effect, which promotes a slag film formed between liquid iron and ceramic cup and results in local corrosion. The corrosion of the samples deepened with increasing temperature of liquid iron and slag from 1,623 K to 1,823 K. The variation of slag composition had greater influence on the erosion degree than that of rotational speed in this experiment. Taking these results into account the ceramic cup composition should be close to slag composition to decrease the chemical reaction. A microporous and strong material should be applied for ceramic cup.

  17. Disintegration and size reduction of slags and metals after melt refining of contaminated metallic wastes

    International Nuclear Information System (INIS)

    Heshmatpour, B.; Copeland, G.L.; Heestand, R.L.

    1981-04-01

    Melting under an oxidizing slag is an attractive method of decontaminating and reducing the volume of radioactively contaminated metal scrap. The contaminants are concentrated in a relatively small volume of slag, which leaves the metal essentially clean. A potential method of permanently disposing of the resulting slags (and metals if necessary) is emplacing them into deep shale by grout hydrofracture. Suspension in grout mixtures requires that the slag and metal be granular. The feasibility of size-reducing slags and disintegrating metals and subsequently incorporating both into grout mixtures was demonstrated. Various types of slags were crushed with a small jaw crusher into particles smaller than 3 mm. Several metals were also melted and water-blasted into coarse metal powder or shot ranging in size from 0.05 to 3 mm. A simple low-pressure water atomizer having a multiple nozzle with a converging-line jet stream was developed and used for this purpose. No significant slag dust and steam were generated during slag crushing and liquid-metal water-blasting tests, indicating that contamination can be well contained within the system. The crushed slags and the coarse metal powders were suspendable in group fluids, which indicates probable disposability by shale hydrofracture. The granulation of slags and metals facilitates their containment, transport, and storage

  18. Evaluation of copper slag to catalyze advanced oxidation processes for the removal of phenol in water

    International Nuclear Information System (INIS)

    Huanosta-Gutiérrez, T.; Dantas, Renato F.; Ramírez-Zamora, R.M.; Esplugas, S.

    2012-01-01

    Highlights: ► We evaluate the use of an industrial residue (copper slag) as catalyst in water treatment. ► The copper slag was effective to remove organic pollutants (phenol) from water. ► During experimentation, Cu and Fe leaching were not higher than the acceptable levels. ► Slag/H 2 O 2 /UV and slag/H 2 O 2 treatments promoted biodegradability increment of the contaminated water. ► The control of the reaction time would minimize the environmental impact of the produced effluents in terms of acute toxicity. - Abstract: The aim of this work was to evaluate the use of copper slag to catalyze phenol degradation in water by advanced oxidation processes (AOPs). Copper slag was tested in combination with H 2 O 2 (slag/H 2 O 2 ) and H 2 O 2 /UV (slag/H 2 O 2 /UV). The studied methods promoted the complete photocatalytic degradation of phenol. Besides, they were able to reduce about 50% the TOC content in the samples. Slag/H 2 O 2 /UV and slag/H 2 O 2 treatments have favored biodegradability increment along the reaction time. Nevertheless, the irradiated method achieved higher values of the biodegradability indicator (BOD 5 /TOC). The toxicity assessment indicated the formation of more toxic compounds in both treatments. However, the control of the reaction time would minimize the environmental impact of the effluents.

  19. Rheological behavior and constitutive equations of heterogeneous titanium-bearing molten slag

    Science.gov (United States)

    Jiang, Tao; Liao, De-ming; Zhou, Mi; Zhang, Qiao-yi; Yue, Hong-rui; Yang, Song-tao; Duan, Pei-ning; Xue, Xiang-xin

    2015-08-01

    Experimental studies on the rheological properties of a CaO-SiO2-Al2O3-MgO-TiO2-(TiC) blast furnace (BF) slag system were conducted using a high-temperature rheometer to reveal the non-Newtonian behavior of heterogeneous titanium-bearing molten slag. By measuring the relationships among the viscosity, the shear stress and the shear rate of molten slags with different TiC contents at different temperatures, the rheological constitutive equations were established along with the rheological parameters; in addition, the non-Newtonian fluid types of the molten slags were determined. The results indicated that, with increasing TiC content, the viscosity of the molten slag tended to increase. If the TiC content was less than 2wt%, the molten slag exhibited the Newtonian fluid behavior when the temperature was higher than the critical viscosity temperature of the molten slag. In contrast, the molten slag exhibited the non-Newtonian pseudoplastic fluid characteristic and the shear thinning behavior when the temperature was less than the critical viscosity temperature. However, if the TiC content exceeded 4wt%, the molten slag produced the yield stress and exhibited the Bingham and plastic pseudoplastic fluid behaviors when the temperature was higher and lower than the critical viscosity temperature, respectively. When the TiC content increased further, the yield stress of the molten slag increased and the shear thinning phenomenon became more obvious.

  20. ACR coal 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This publication is a comprehensive reference document on production, exports, prices and demand of coal in world markets. A forecast of demand by coal type and country up to the year 2000 is provided. Statistics of the Australian export industry are complemented by those of South Africa, USA, Canada, Indonesia, China, C.I.S. and Colombia. A very comprehensive coal quality specification for nearly all the coal brands exported from Australia, as well as leading non-Australian coal brands, is included.

  1. Assessing coal burnout

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, A. [Pacific Power, Sydney, NSW (Australia)

    1999-11-01

    Recent research has allowed a quantitative description of the basic process of burnout for pulverized coals to be made. The Cooperative Research Centre for Black Coal Utilization has built on this work to develop a coal combustion model which will allow plant engineers and coal company representatives to assess their coals for combustion performance. The paper describes the model and its validation and outlines how it is run. 2 figs.

  2. Natural gas cooling: Part of the solution

    International Nuclear Information System (INIS)

    Jones, D.R.

    1992-01-01

    This paper reviews and compares the efficiencies and performance of a number of gas cooling systems with a comparable electric cooling system. The results show that gas cooling systems compare favorably with the electric equivalents, offering a new dimension to air conditioning and refrigeration systems. The paper goes on to compare the air quality benefits of natural gas to coal or oil-burning fuel systems which are used to generate the electricity for the electric cooling systems. Finally, the paper discusses the regulatory bias that the author feels exists towards the use of natural gas and the need for modification in the existing regulations to provide a 'level-playing field' for the gas cooling industry

  3. Stochastic cooling

    International Nuclear Information System (INIS)

    Bisognano, J.; Leemann, C.

    1982-03-01

    Stochastic cooling is the damping of betatron oscillations and momentum spread of a particle beam by a feedback system. In its simplest form, a pickup electrode detects the transverse positions or momenta of particles in a storage ring, and the signal produced is amplified and applied downstream to a kicker. The time delay of the cable and electronics is designed to match the transit time of particles along the arc of the storage ring between the pickup and kicker so that an individual particle receives the amplified version of the signal it produced at the pick-up. If there were only a single particle in the ring, it is obvious that betatron oscillations and momentum offset could be damped. However, in addition to its own signal, a particle receives signals from other beam particles. In the limit of an infinite number of particles, no damping could be achieved; we have Liouville's theorem with constant density of the phase space fluid. For a finite, albeit large number of particles, there remains a residue of the single particle damping which is of practical use in accumulating low phase space density beams of particles such as antiprotons. It was the realization of this fact that led to the invention of stochastic cooling by S. van der Meer in 1968. Since its conception, stochastic cooling has been the subject of much theoretical and experimental work. The earliest experiments were performed at the ISR in 1974, with the subsequent ICE studies firmly establishing the stochastic cooling technique. This work directly led to the design and construction of the Antiproton Accumulator at CERN and the beginnings of p anti p colliding beam physics at the SPS. Experiments in stochastic cooling have been performed at Fermilab in collaboration with LBL, and a design is currently under development for a anti p accumulator for the Tevatron

  4. Numerical investigation of slag formation in an entrained-flow gasifier

    Science.gov (United States)

    Zageris, G.; Geza, V.; Jakovics, A.

    2018-05-01

    A CFD mathematical model for an entrained-flow gasifier is constructed – the model of an actual gasifier is rendered in 3D and appropriately meshed. Then, the turbulent gas flow in the gasifier is modeled with the realizable k-ε approach, taking devolatilization, combustion and coal gasification in account. Various such simulations are conducted, obtaining results for different air inlet positions and by tracking particles of varying sizes undergoing devolatilization and gasification. The model identifies potential problematic zones where most particles collide with the gasifier walls, indicating risk regions where ash deposits could most likely form. In conclusion, effects on the formation of an ash layer of air inlet positioning and particle size allowed in the main gasifier tank are discussed, and viable solutions such as radial inlet positioning for decreasing the amount of undesirable deposits are proposed. We also conclude that the particular chemical reactions that take place inside the gasifier play a significant role in determining how slagging occurs inside a gasifier.

  5. FUNGISTATIC PROPERTIES OF GRANULATED BLASTFURNACE SLAG AND RELATED SLAG-CONTAINING CEMENTS

    Directory of Open Access Journals (Sweden)

    Julius Strigac

    2016-03-01

    Full Text Available The article deals with studying the antifungal effect of ground granulated blastfurnace slag (GGBS and the cements made from it. Antifungal effects were tested on the fungi using the procedure given in the Czech national standard CSN 72 4310: 1977 - Testing the mould proofness properties of building products and materials. A mixture of the fungi Aspergillus niger, Chaetomium globosum, Penicillium funiculosum, Paecilomyces variotii and Gliocladium virens was used for testing. The scale for evaluating mould proofness properties according to CSN 72 4310: 1977 is from 0 to 5 in degree of fungi growth, where a value of 0 means that no growth of fungi occurs and the building products and materials possess fungistatic properties. The study confirms the fungistatic propeties of GGBS with mould proofness property 0. The addition of GGBS to cements from 65 wt.% to 95 wt.% ensures the achieving of a fungistatic environment, which enables the production of fungistatic blastfurnace cements CEM III/A 32.5 N (with GGBS content of 65 wt.%, CEM III/B 32.5 N and CEM III/C 32.5 N with mould proofness property 0.

  6. Method and Apparatus for Assessing the Properties of Slags

    Directory of Open Access Journals (Sweden)

    Biernat S.

    2017-09-01

    Full Text Available A special Slag-Prop Cu database has been developed to archive data from laboratory and industrial tests related to post-reduction slags. In order to enrich the data areas, it was decided to design a system for measuring the temperature of the liquid slag and its viscosity. Objectives of research work are to gather information on the properties of post-slags such as the temperature of liquid slag and its viscosity. The discussed issues are especially important in the foundry practice. Designed research stand and using of database applications can greatly facilitate the work of metallurgists, foundrymen, technologists and scientists. The viscosity measurement was developed and presented earlier. The author’s analytical methodology was supplemented by a thyristor measuring system (described in the article. The system temperature measurement can be performed simultaneously in 3 ways to reduce the measurement error. Measurement of the voltage mV - using the Seebeck effect can be measured throughout the entire range of thermocouple resistance, up to 1300 °C. Direct temperature measurement °C - measurement only below 1000 °C. Additional measurement - the measurement can also be read from the pyrometer set above the bath. The temperature and the reading frequency depend on the device itself. The principle of measurement is that in a molten metal / slag crucible, we put a N-type thermocouple. The thermocouples are hung by means of a tripod above the crucible and placed in a crucible. The thermocouple is connected to a compensating line dedicated to this type of thermocouple. The cable is in turn connected to a special multimeter that has the ability to connect to a computer and upload results. Temperature measurement can be performed simultaneously in 3 ways to reduce the measurement error. The Sn-Pb alloy has been subjected to testing for proper operation of the device. In this foot should be observed the supercooling of the liquid, which initiates

  7. A very cool cooling system

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    The NA62 Gigatracker is a jewel of technology: its sensor, which delivers the time of the crossing particles with a precision of less than 200 picoseconds (better than similar LHC detectors), has a cooling system that might become the precursor to a completely new detector technique.   The 115 metre long vacuum tank of the NA62 experiment. The NA62 Gigatracker (GTK) is composed of a set of three innovative silicon pixel detectors, whose job is to measure the arrival time and the position of the incoming beam particles. Installed in the heart of the NA62 detector, the silicon sensors are cooled down (to about -20 degrees Celsius) by a microfluidic silicon device. “The cooling system is needed to remove the heat produced by the readout chips the silicon sensor is bonded to,” explains Alessandro Mapelli, microsystems engineer working in the Physics department. “For the NA62 Gigatracker we have designed a cooling plate on top of which both the silicon sensor and the...

  8. X-ray diffractometry of steam cured ordinary Portland and blast-furnace-slag cements

    International Nuclear Information System (INIS)

    Camarini, G.; Djanikian, J.G.

    1994-01-01

    This work studies some aspects of the phases produced by hydration of ordinary and blast-furnace-slag cements, at normal conditions and steam cured (60 and 95 0 C), using an X-ray diffraction technique. The blast-furnace-slag cement was a mixture of 50% of ordinary Portland cement and 50% of blast-furnace-slag (separately grinding). After curing the X-ray diffraction reveals that, in relation to ordinary Portland cement, the main phases in blast-furnace-slag cement are hydrated silicates and aluminates, hydro garnet, etringitte and mono sulphate. After steam curing the hydration of blast-furnace-slag cement proceeds. This is a result of the slag activation by the curing temperature. (author). 8 refs., 3 figs., 1 tab

  9. Utilization of High-Temperature Slags From Metallurgy Based on Crystallization Behaviors

    Science.gov (United States)

    Sun, Yongqi; Zhang, Zuotai

    2018-05-01

    Here, following the principle of modifying crystallization behaviors, including avoidance and optimization, we review recent research on the utilization of hot slags. Because of the high-temperature property (1450-1650°C), the utilization of hot slags are much different from that of other wastes. We approach this issue from two main directions, namely, material recycling and heat utilization. From the respect of material recycling, the utilization of slags mainly follows total utilization and partial utilization, whereas the heat recovery from slags follows two main paths, namely, physical granulation and chemical reaction. The effective disposal of hot slags greatly depends on clarifying the crystallization behaviors, and thus, we discuss some optical techniques and their applicable scientific insights. For the purpose of crystallization avoidance, characterizing the glass-forming ability of slags is of great significance, whereas for crystallization modification, the selection of chemical additives and control of crystallization conditions comprise the central routes.

  10. Effect of Iron Redox Equilibrium on the Foaming Behavior of MgO-Saturated Slags

    Science.gov (United States)

    Park, Youngjoo; Min, Dong Joon

    2018-04-01

    In this study, the foaming index of CaO-SiO2-FetO and CaO-SiO2-FetO-Al2O3 slags saturated with MgO was measured to understand the relationship between their foaming behavior and physical properties. The foaming index of MgO-saturated slags increases with the FetO content due to the redox equilibrium of FetO. Experimental results indicated that MgO-saturated slag has relatively high ferric ion concentration, and the foaming index increases due to the effect of ferric ion. Therefore, the foaming behavior of MgO-saturated slag is more reasonably explained by considering the effect of ferric ion on the estimation of slag properties such as viscosity, surface tension, and density. Specifically, the estimation of slag viscosity was additionally verified by NBO/T, and this is experimentally obtained through Raman spectroscopy.

  11. Study of flame combustion of off-design binary coal blends in steam boilers

    Science.gov (United States)

    Kapustyanskii, A. A.

    2017-07-01

    Changes in the structure of the fuel consumption by the thermal power stations of Ukraine caused by failure in supplying anthracite from the Donets Basin are analyzed and the major tasks of maintaining the functioning of the coal industry are formulated. The possibility of using, in the near future, the flame combustion of off-design solid fuels in the power boilers of the thermal power plants and combined heat and power plants is studied. The article presents results of expert tests of the TPP-210A and TP-15 boilers under flame combustion of mixtures of anthracites, lean coal, and the coal from the RSA in various combinations. When combusting, such mixtures have higher values of the combustibles yield and the ash fusibility temperature. The existence of the synergetic effect in the flame combustion of binary coal blends with different degrees of metamorphism is discussed. A number of top-priority measures have been worked out that allow for switching over the boilers designed to be fired with anthracite to using blends of coals of different ranks. Zoned thermal analysis of the TP-15 boiler furnace was performed for numerical investigation of the temperature distribution between the furnace chamber zones and exploration of the possibility of the liquid slag disposal and the temperature conditions for realization of this process. A positive result was achieved by combusting anthracite culm (AC), the coal from the RSA, and their mixtures with lean coal within the entire range of the working loads of the boilers in question. The problems of normalization of the liquid slag flow were also successfully solved without closing the slag notch. The results obtained by balance experiments suggest that the characteristics of the flame combustion of a binary blend, i.e., the temperature conditions in the furnace, the support flame values, and the degree of the fuel burnout, are similar to the characteristics of the flame of the coal with a higher reactive capacity, which

  12. Cooling pancakes

    International Nuclear Information System (INIS)

    Bond, J.R.; Wilson, J.R.

    1984-01-01

    In theories of galaxy formation with a damping cut-off in the density fluctuation spectrum, the first non-linear structures to form are Zeldovich pancakes in which dissipation separates gas from any collisionless dark matter then present. One-dimensional numerical simulations of the collapse, shock heating, and subsequent thermal evolution of pancakes are described. Neutrinos (or any other cool collisionless particles) are followed by direct N-body methods and the gas by Eulerian hydrodynamics with conduction as well as cooling included. It is found that the pressure is relatively uniform within the shocked region and approximately equals the instantaneous ram pressure acting at the shock front. An analytic theory based upon this result accurately describes the numerical calculations. (author)

  13. Cool Sportswear

    Science.gov (United States)

    1982-01-01

    New athletic wear design based on the circulating liquid cooling system used in the astronaut's space suits, allows athletes to perform more strenuous activity without becoming overheated. Techni-Clothes gear incorporates packets containing a heat-absorbing gel that slips into an insulated pocket of the athletic garment and is positioned near parts of the body where heat transfer is most efficient. A gel packet is good for about one hour. Easily replaced from a supply of spares in an insulated container worn on the belt. The products, targeted primarily for runners and joggers and any other athlete whose performance may be affected by hot weather, include cooling headbands, wrist bands and running shorts with gel-pack pockets.

  14. Cooling systems

    International Nuclear Information System (INIS)

    Coutant, C.C.

    1978-01-01

    Progress on the thermal effects project is reported with regard to physiology and distribution of Corbicula; power plant effects studies on burrowing mayfly populations; comparative thermal responses of largemouth bass from northern and southern populations; temperature selection by striped bass in Cherokee Reservoir; fish population studies; and predictive thermoregulation by fishes. Progress is also reported on the following; cause and ecological ramifications of threadfin shad impingement; entrainment project; aquaculture project; pathogenic amoeba project; and cooling tower drift project

  15. Marble waste characterization as a desulfurizing slag component for steel

    International Nuclear Information System (INIS)

    Coleti, J.L.; Grillo, F.F.; Tenorio, J.A.S.; De Oliveira, J.R.

    2014-01-01

    The current steel market requires from steel plants better quality of its products. As a result, steel plants need to search for improvements and costs reduction in its process. Hence, the residue of marble containing significant quantities of calcium and magnesium carbonates, raw materials of steel refining slag, was characterized in order to replace the conventional lime used. Therefore, it will be possible to reduce the cost and volume of waste produced by the ornamental rock industry. The following methods were applied to test the waste potential: SEM with EDS, x-ray diffraction, x-ray fluorescence (EDX), Thermogravimetry (TG) and analysis of surface area and particle size by the BET method using dispersion leisure. The results indicated the feasibility of waste as raw material in the composition of desulfurizing slags. (author)

  16. Simulation of petcoke gasification in slagging moving bed reactors

    Energy Technology Data Exchange (ETDEWEB)

    Nagpal, Soumitro; Sarkar, T.K.; Sen, P.K. [Research and Development Center, Engineers India Limited, Gurgaon 122001 (India)

    2005-03-25

    A mathematical model for simulation of moving bed petcoke gasifiers was developed. The model introduces a new feed characterization method, gas-phase resistance and volatilization models. The model is validated using reported data for a slagging gasifier. Effect of feed oxygen-to-coke and steam-to-coke ratios and feed coke rates on gasification performance was examined. Slagging zone moving bed gasifier operation with very high petcoke fluxes of over 4000 kg/m{sup 2}/h was possible with high petcoke conversion. Peak gas temperatures exceeded 1500 {sup o}C. Fluxes higher than 5000 kg/m{sup 2}/h are limited by an approach to fluidization of small particles in the combustion zone. The moving bed gasifier performance was found superior to performance of an entrained flow gasifier (EFG) with respect to energy efficiency and oxygen consumption.

  17. Control system for high-temperature slagging incinerator plant

    International Nuclear Information System (INIS)

    Matsuzaki, Yuji

    1986-01-01

    Low-level radioactive wastes generated in the nuclear generating plants are increasing year by year and to dispose them safely constitutes a big problem for the society. A few years ago, as the means of reducing them to as little volume as possible by incinerating and fusing the wastes, a high-temperature slagging incinerating method was developed, and this method is highly assessed. JGC Corp. has introduced that system technology and in order to prove the capacity of disposal and salubrity of the plant, and have constructed a full-sized pilot plant, then obtained the operational record and performance as they had planned. This report introduces the general processing of the wastes from their incineration and fusion as well as process control technology characteristic to high-temperature slagging incinerator furnaces and sensor technology. (author)

  18. Coal information 1996

    International Nuclear Information System (INIS)

    1997-01-01

    Coal Information (1997 edition) is the latest edition of a publication that has been produced annually by the IEA since 1983. The report is intended to provide both Member countries of the OECD and those employed in all sectors of the coal industry with information on current world coal market trends and long-term prospects. It includes information on coal prices, demand, trade, supply, production capacity, transport, environmental issues (including emission standards for coal-fired boilers), coal ports, coal-fired power stations and coal used in non -OECD countries. Part I of the publication contains a wide ranging review of world coal market developments in 1996 and current prospects to 2010. The review is based on historical data of OECD energy supply and demand, data on other world regions, projections of OECD coal supply, demand and trade and information provided by the CIAB. Part II provides, in tabular and graphical form, a more detailed and comprehensive statistical picture of coal developments and future prospects for coal in the OECD, by region and for individual Member countries. Readers interested in projections are strongly advised to read the notes for individual countries in Principles and Definitions in Part II. Coal statistics for non-OECD countries are presented in Part III of the book. Summary data are available on hard coal supply and end-use statistics for about 40 countries and regions world-wide. Data are based on official national submissions to the United Nations in Geneva and New York, national energy publications, information provided to the IEA Secretariat by national statistical offices as well as other unofficial Secretariat sources. Further information on coal used in non-OECD countries is published annually by the IEA in Energy Statistics and Balances of Non-OECD Countries. Also included in Part III are the Survey of Coal Ports world-wide and the Survey of Coal-fired Power Stations in coal-importing countries

  19. Effects of slag-based silicon fertilizer on rice growth and brown-spot resistance.

    Science.gov (United States)

    Ning, Dongfeng; Song, Alin; Fan, Fenliang; Li, Zhaojun; Liang, Yongchao

    2014-01-01

    It is well documented that slag-based silicon fertilizers have beneficial effects on the growth and disease resistance of rice. However, their effects vary greatly with sources of slag and are closely related to availability of silicon (Si) in these materials. To date, few researches have been done to compare the differences in plant performance and disease resistance between different slag-based silicon fertilizers applied at the same rate of plant-available Si. In the present study both steel and iron slags were chosen to investigate their effects on rice growth and disease resistance under greenhouse conditions. Both scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the effects of slags on ultrastructural changes in leaves of rice naturally infected by Bipolaris oryaze, the causal agent of brown spot. The results showed that both slag-based Si fertilizers tested significantly increased rice growth and yield, but decreased brown spot incidence, with steel slag showing a stronger effect than iron slag. The results of SEM analysis showed that application of slags led to more pronounced cell silicification in rice leaves, more silica cells, and more pronounced and larger papilla as well. The results of TEM analysis showed that mesophyll cells of slag-untreated rice leaf were disorganized, with colonization of the fungus (Bipolaris oryzae), including chloroplast degradation and cell wall alterations. The application of slag maintained mesophyll cells relatively intact and increased the thickness of silicon layer. It can be concluded that applying slag-based fertilizer to Si-deficient paddy soil is necessary for improving both rice productivity and brown spot resistance. The immobile silicon deposited in host cell walls and papillae sites is the first physical barrier for fungal penetration, while the soluble Si in the cytoplasm enhances physiological or induced resistance to fungal colonization.

  20. Experimental investigation of basic oxygen furnace slag used as aggregate in asphalt mixture.

    Science.gov (United States)

    Xue, Yongjie; Wu, Shaopeng; Hou, Haobo; Zha, Jin

    2006-11-16

    Chinese researchers have commenced a great deal of researches on the development of application fields of basic oxygen steel making furnace slag (BOF slag) for many years. Lots of new applications and properties have been found, but few of them in asphalt mixture of road construction engineering. This paper discussed the feasibility of BOF steel slag used as aggregate in asphalt pavement by two points of view including BOF steel slag's physical and micro-properties as well as steel slag asphalt materials and pavement performances. For the former part, this paper mainly concerned the mechanochemistry and physical changes of the steel slag and studied it by performing XRD, SEM, TG and mercury porosimeter analysis and testing method. In the second part, this paper intended to use BOF steel slag as raw material, and design steel slag SMA mixture. By using traditional rutting test, soak wheel track and modified Lottman test, the high temperature stability and water resistance ability were tested. Single axes compression test and indirect tensile test were performed to evaluate the low temperature crack resistance performance and fatigue characteristic. Simultaneously, by observing steel slag SMA pavement which was paved successfully. A follow-up study to evaluate the performance of the experimental pavement confirmed that the experimental pavement was comparable with conventional asphalt pavement, even superior to the later in some aspects. All of above test results and analysis had only one main purpose that this paper validated the opinion that using BOF slag in asphalt concrete is feasible. So this paper suggested that treated and tested steel slag should be used in a more extensive range, especially in asphalt mixture paving projects in such an abundant steel slag resource region.

  1. Coal fly ash-slag-based geopolymers: microstructure and metal leaching.

    Science.gov (United States)

    Izquierdo, Maria; Querol, Xavier; Davidovits, Joseph; Antenucci, Diano; Nugteren, Henk; Fernández-Pereira, Constantino

    2009-07-15

    This study deals with the use of fly ash as a starting material for geopolymeric matrices. The leachable concentrations of geopolymers were compared with those of the starting fly ash to evaluate the retention of potentially harmful elements within the geopolymer matrix. Geopolymer matrices give rise to a leaching scenario characterised by a highly alkaline environment, which inhibits the leaching of heavy metals but may enhance the mobilization of certain oxyanionic species. Thus, fly ash-based geopolymers were found to immobilize a number of trace pollutants such as Be, Bi, Cd, Co, Cr, Cu, Nb, Ni, Pb, Sn, Th, U, Y, Zr and rare earth elements. However, the leachable levels of elements occurring in their oxyanionic form such as As, B, Mo, Se, V and W were increased after geopolymerization. This suggests that an optimal dosage, synthesis and curing conditions are essential in order to obtain a long-term stable final product that ensures an efficient physical encapsulation.

  2. Coal fly ash-slag-based geopolymers: Microstructure and metal leaching

    Energy Technology Data Exchange (ETDEWEB)

    Izquierdo, Maria, E-mail: mariaizq@ija.csic.es [Institute of Earth Sciences ' Jaume Almera' -CSIC, Lluis Sole Sabaris s/n 08028 Barcelona (Spain); Querol, Xavier [Institute of Earth Sciences ' Jaume Almera' -CSIC, Lluis Sole Sabaris s/n 08028 Barcelona (Spain); Davidovits, Joseph [Cordi-Geopolymere, Espace Creatis, Z.A. Bois de la Chocque 02100 Saint-Quentin (France); Antenucci, Diano [Institut Scientifique de Service Public (ISSeP) 200, rue du Chera, B-4000 Liege (Belgium); Nugteren, Henk [Delft University of Technology, Faculty of Applied Sciences, DelftChemTech, Particle Technology Group, Julianalaan 136, 2628 BL Delft (Netherlands); Fernandez-Pereira, Constantino [University of Seville, School of Industrial Engineering, Department of Chemical and Environmental Engineering, Camino de los Descubrimientos s/n, 41092 Seville (Spain)

    2009-07-15

    This study deals with the use of fly ash as a starting material for geopolymeric matrices. The leachable concentrations of geopolymers were compared with those of the starting fly ash to evaluate the retention of potentially harmful elements within the geopolymer matrix. Geopolymer matrices give rise to a leaching scenario characterised by a highly alkaline environment, which inhibits the leaching of heavy metals but may enhance the mobilization of certain oxyanionic species. Thus, fly ash-based geopolymers were found to immobilise a number of trace pollutants such as Be, Bi, Cd, Co, Cr, Cu, Nb, Ni, Pb, Sn, Th, U, Y, Zr and rare earth elements. However, the leachable levels of elements occurring in their oxyanionic form such as As, B, Mo, Se, V and W were increased after geopolymerization. This suggests that an optimal dosage, synthesis and curing conditions are essential in order to obtain a long-term stable final product that ensures an efficient physical encapsulation.

  3. Coal fly ash-slag-based geopolymers: Microstructure and metal leaching

    International Nuclear Information System (INIS)

    Izquierdo, Maria; Querol, Xavier; Davidovits, Joseph; Antenucci, Diano; Nugteren, Henk; Fernandez-Pereira, Constantino

    2009-01-01

    This study deals with the use of fly ash as a starting material for geopolymeric matrices. The leachable concentrations of geopolymers were compared with those of the starting fly ash to evaluate the retention of potentially harmful elements within the geopolymer matrix. Geopolymer matrices give rise to a leaching scenario characterised by a highly alkaline environment, which inhibits the leaching of heavy metals but may enhance the mobilization of certain oxyanionic species. Thus, fly ash-based geopolymers were found to immobilise a number of trace pollutants such as Be, Bi, Cd, Co, Cr, Cu, Nb, Ni, Pb, Sn, Th, U, Y, Zr and rare earth elements. However, the leachable levels of elements occurring in their oxyanionic form such as As, B, Mo, Se, V and W were increased after geopolymerization. This suggests that an optimal dosage, synthesis and curing conditions are essential in order to obtain a long-term stable final product that ensures an efficient physical encapsulation.

  4. Research and development plan for the Slagging Pyrolysis Incinerator

    International Nuclear Information System (INIS)

    Hedahl, T.G.; McCormack, M.D.

    1979-01-01

    Objective is to develop an incinerator for processing disposed transuranium waste. This R and D plan describes the R and D efforts required to begin conceptual design of the Slagging Pyrolysis Incinerator (Andco-Torrax). The program includes: incinerator, off-gas treatment, waste handling, instrumentation, immobilization analyses, migration studies, regulations, Belgium R and D test plan, Disney World test plan, and remote operation and maintenance

  5. Reducing treatment of coppersmelting slag: Thermodynamic analysis of impurities behavior

    Science.gov (United States)

    Komkov, Alexey; Kamkin, Rostislav

    2011-01-01

    A thermodynamic mathematical model, describing behavior of Pb, Zn, and As during reducing slag cleaning in the Vanyukov furnace has been developed. Using a developed model, the influence of different factors, such as temperature, oxygen partial pressure, the ratio of the formed phases on the behavior of impurities, was analyzed. It was found that arsenic can significantly move to the bottom phase, and zinc can be significantly vaporized under conditions in the Vanyukov furnace.

  6. Blasted copper slag as fine aggregate in Portland cement concrete.

    Science.gov (United States)

    Dos Anjos, M A G; Sales, A T C; Andrade, N

    2017-07-01

    The present work focuses on assessing the viability of applying blasted copper slag, produced during abrasive blasting, as fine aggregate for Portland cement concrete manufacturing, resulting in an alternative and safe disposal method. Leaching assays showed no toxicity for this material. Concrete mixtures were produced, with high aggregate replacement ratios, varying from 0% to 100%. Axial compressive strength, diametrical compressive strength, elastic modulus, physical indexes and durability were evaluated. Assays showed a significant improvement in workability, with the increase in substitution of fine aggregate. With 80% of replacement, the concrete presented lower levels of water absorption capacity. Axial compressive strength and diametrical compressive strength decreased, with the increase of residue replacement content. The greatest reductions of compressive strength were found when the replacement was over 40%. For tensile strength by diametrical compression, the greatest reduction occurred for the concrete with 80% of replacement. After the accelerated aging, results of mechanic properties showed a small reduction of the concrete with blasted copper slag performance, when compared with the reference mixture. Results indicated that the blasted copper slag is a technically viable material for application as fine aggregate for concrete mixtures. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. The use of activated slags as immobilisation matrices for ILW

    International Nuclear Information System (INIS)

    Milestone, N. B.; Bai, Y.; Yang, C. H.; Shi, Y. J.; Li, X. C.

    2008-01-01

    Composite cements where large amounts of blast furnace slag (BFS) replace Portland cement are currently used for immobilisation of ILW. Hydration of BFS is activated by the small amount of OPC present but the amount of reaction that occurs is limited at ambient temperatures. Increasing the temperature increases the hydration of the BFS but large amounts still remain unreacted, leaving a porous matrix where the capillary pores remain filled with a highly alkaline solution. This solution causes corrosion of reactive metals giving rise to expansive reactions and hydrogen release, and it can destroy the structure of zeolites releasing the adsorbed species. Apart from OPC, BFS hydration can be activated by other compounds such as hydroxides, sulphates, silicates, and calcium aluminate cements. The use of these alternatives gives rise to binders such as ettringite and straetlingite which have a different chemistry where the pore solution has a lower pH. Corrosion of metals does not readily occur in these binders. This may be due to the reduced pH but could also arise from the lack of pore water, as these binders bind more water in their structure so that it is not available for transport of ionic species. This extra water binding also has potential for immobilisation of sludges where high w/s ratios are necessitated by the need to transport the sludge. This paper will review some of the alternative activators for slag hydration and present experimental results on several systems where slag has been activated with compounds other than OPC. (authors)

  8. Properties of slag concrete for low-level waste containment

    International Nuclear Information System (INIS)

    Langton, C.A.; Wong, P.B.

    1991-01-01

    Ground granulated blast furnace slag was incorporated in the concrete mix used for construction of low-level radioactive waste disposal vaults. The vaults were constructed as six 100 x 100 x 25 ft cells with each cell sharing internal walls with the two adjacent cells. The vaults were designed to contain a low-level radioactive wasteform called saltstone and to isolate the saltstone from the environment until the landfill is closed. Closure involves backfilling with native soil, installation of clay cap, and run-off control. The design criteria for the slag-substituted concrete included compressive strength, 4000 psi after 28 days; slump, 6 inch; permeability, less than 10 -7 cm/sec; and effective nitrate, chromium and technetium diffusivities of 10 -8 , 10 -12 and 10 -12 cm 2 /sec, respectively. The reducing capacity of the slag resulted in chemically reducing Cr +6 to Cr +3 and Tc +7 to Tc +4 and subsequent precipitation of the respective hydroxides in the alkaline pore solution. Consequently, the concrete vault enhances containment of otherwise mobile waste ions and contributes to the overall protection of the groundwater at the disposal site

  9. Selective Sulfidation of Lead Smelter Slag with Sulfur

    Science.gov (United States)

    Han, Junwei; Liu, Wei; Wang, Dawei; Jiao, Fen; Qin, Wenqing

    2016-02-01

    The selective sulfidation of lead smelter slag with sulfur was studied. The effects of temperature, sulfur dosage, carbon, and Na salts additions were investigated based on thermodynamic calculation. The results indicated that more than 96 pct of zinc in the slag could be converted into sulfides. Increasing temperature, sulfur dosage, or Na salts dosage was conducive to the sulfidation of the zinc oxides in the slag. High temperature and excess Na salts would result in the more consumption of carbon and sulfur. Carbon addition not only promoted the selective sulfidation but reduced the sulfur dosage and eliminated the generation of SO2. Iron oxides had a buffering role on the sulfur efficient utilization. The transformation of sphalerite to wurtzite was feasible under reducing condition at high temperature, especially above 1273 K (1000 °C). The growth of ZnS particles largely depended upon the roasting temperature. They were significantly increased when the temperature was above 1273 K (1000 °C), which was attributed to the formation of a liquid phase.

  10. X-ray diffraction study of slags forming during corrosion resistant steel production

    International Nuclear Information System (INIS)

    Slavov, V.I.; Zadorozhnaya, V.N.; Shurygina, A.V.

    1990-01-01

    Using X-ray diffraction analysis slags, forming during corrosion-resistant 12Kh18N10T grade steel production by two flowsheets, are studied. Standard two-slag technology of steel production does not provide efficient disintegration of chromospinelides in slags, gives high steel contamination with respect to nonmetallic impurities, coarse structure and, as a consequence, presence of macrodefects on rolled products surface. One-slag steel melting technology with titanium alloying of the steel at vacuum causes fast removal of chromospinelides at the beginning of reduction period, promotes titanium absorption by the steel, refines nonmetallic inclusions, provides more fine structure and steel plasticity, removes surface defects

  11. Comparison of possibilities the blast furnace and cupola slag utilization by concrete production

    Directory of Open Access Journals (Sweden)

    D. Baricová

    2010-04-01

    Full Text Available In process of pig iron and cast iron production secondary raw materials and industrial wastes are formed The most abundant secondaryproduct originating in these processes are furnace slag. Blast furnace slag and cupola furnace slag originates from melting of gangue parts of metal bearing materials, slag forming additions and coke ash. In general, slag are compounds of oxides of metallic and non-metallic elements, which form chemical compounds and solutions with each other and also contain small volume of metals, sulfides of metals and gases. Chemical, mineralogical and physical properties of slag determinate their utilisation in different fields of industry.The paper presents results from the research of the blast furnace and cupola furnace slag utilization in the concrete production. Pilotexperiments of the concrete production were performed, by that the blast furnace and cupola furnace slag with a fractions of 0–4mm;4–8mm; 8–16mm were used as a natural substitute. A cupola furnace slag and combination of the blast furnace and cupola furnace slagwere used in the experiments. The analysis results show that such concretes are suitable for less demanding applications.

  12. Visualisation and quantification of heavy metal accessibility in smelter slags: The influence of morphology on availability

    International Nuclear Information System (INIS)

    Morrison, Anthony L.; Swierczek, Zofia; Gulson, Brian L.

    2016-01-01

    The Imperial Smelting Furnace (ISF) for producing lead and zinc simultaneously has operated on four continents and in eleven countries from the 1950's. One of the process changes that the ISF introduced was the production of a finely granulated slag waste. Although this slag contained significant amounts of residual lead (Pb) and zinc (Zn), because of its glassy nature it was considered environmentally benign. From the Cockle Creek smelter near Boolaroo at the northern end of Lake Macquarie, NSW, Australia, it is estimated that around 2.1 million tonnes of the fine slag was distributed into the community and most remains where it was originally utilised. Residual tonnages of slag of this magnitude are common worldwide wherever the ISF operated. Studies of base metal smelting slags have concluded that mineralogical and morphological characteristics of the slag play a critical role in moderating environmental release of toxic elements. Scanning electron microscopy (SEM) and microanalysis of the ISF slags has shown that the Pb and associated elements are present as discrete nodules (∼6–22 μm) in the slag and that they are not associated with Zn which is contained in the glass slag phase. Using an automated SEM and analysis technique (QEMSCAN"®) to “map” the mineralogical structure of the particles, it was possible to quantitatively determine the degree of access infiltrating fluids might have to the reaction surface of the Pb phases. The level of access decreases with increasing particle size, but in even the largest sized particles (−3350 + 2000 μm) nearly 80% of the Pb-containing phases were totally or partially accessible. These results provide evidence that the toxic elements in the slags are not contained by the glassy phase and will be vulnerable to leaching over time depending on their individual phase reactivity. - Highlights: • QEMSCAN"® allowed determination of access to infiltrating fluids to Pb in smelter slags. • Pb and associated

  13. An Analysis of the Mechanical Characteristics and Constitutive Relation of Cemented Mercury Slag

    Directory of Open Access Journals (Sweden)

    Xinwei Li

    2017-01-01

    Full Text Available This study focuses on mercury slag in the Tongren area of Guizhou Province, China. Computed tomography (CT is used with uniaxial and triaxial compression tests to examine the mechanical changes in cemented mercury slag and its formation. The CT results for the uniaxial compression test reveal the overall failure process of the mercury slag structure. Based on the coarse-grained soil triaxial test, a modified Duncan-Chang model is compared with the actual monitoring results and is found to be suitable for the analysis of the slag constitutive model.

  14. Reclamation and reuse of MWI slags under the aspect of ground water protection

    International Nuclear Information System (INIS)

    Lahl, U.; Struth, R.

    1993-01-01

    Some importants aspects of ground water protection are discussed, with regard to MWI-slag reclamation and reuse as construction material. The effects of a treatment process on residual organic compounds of slag material have to be regarded as very positive. Directed chemical influencing of the hydratation process directly after incineration offers new perspectives for generating slag with potentially little and constant elution behaviour. The authors welcome the new, sharpened demands on reuse of MWI-slag in Northrhine-Westfalia. This challenge can be met by the proposed treatment procedure without problems. (orig.) [de

  15. Study of the Mechanism of Liquid Slag Infiltration for Lubrication in Slab Continuous Casting

    Science.gov (United States)

    Zhang, Shaoda; Wang, Qiangqiang; He, Shengping; Wang, Qian

    2018-04-01

    Consistent and uniform lubrication of the solidifying shell, especially in the meniscus, is crucial for the smooth continuous casting operation and production of strands free of surface defects. Thus, the current study established a coupled model to study the inflow behavior of liquid slag to the mold-strand channel, taking the solidification of steel and slag and the periodic oscillation of mold into account. The difficulties and solutions for the simulation were described in detail. The predicted profiles of the slag rim and initial shell were in good agreement with the reports. The main results indicated that liquid slag could be squeezed out and back into the slag pool in a negative strip period while a large amount of liquid slag could infiltrate into the mold-strand channel. Thus, the amount of slag consumed in the negative strip period was relatively small compared with that in the positive strip period. The predicted variation of slag consumption during mold oscillation was periodic, and the average value was 0.274 kg/m2, which agreed well with the slag consumption in industrial practice. The current model can predict and optimize the oscillation parameters aiming at stable lubrication conditions.

  16. Trends in Japanese coal trade

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, S

    1986-01-01

    The author discusses 1) the latest forecast for coal demand in Japan; 2) trends in Japanese steam coal demand, with breakdown by industry; 3) the organization of steam coal supply, with details of the distribution network and of the new coal cartridge system; 4) the demand for metallurgical coal. Other topics outlined include the current status of Japanese coal production, Japanese coal trade, and the development of overseas coal resources. 1 figure, 5 tables.

  17. Gas core reactors for coal gasification

    International Nuclear Information System (INIS)

    Weinstein, H.

    1976-01-01

    The concept of using a gas core reactor to produce hydrogen directly from coal and water is presented. It is shown that the chemical equilibrium of the process is strongly in favor of the production of H 2 and CO in the reactor cavity, indicating a 98 percent conversion of water and coal at only 1500 0 K. At lower temperatures in the moderator-reflector cooling channels the equilibrium strongly favors the conversion of CO and additional H 2 O to CO 2 and H 2 . Furthermore, it is shown the H 2 obtained per pound of carbon has 23 percent greater heating value than the carbon so that some nuclear energy is also fixed. Finally, a gas core reactor plant floating in the ocean is conceptualized which produces H 2 , fresh water and sea salts from coal

  18. Nitrogen in Chinese coals

    Science.gov (United States)

    Wu, D.; Lei, J.; Zheng, B.; Tang, X.; Wang, M.; Hu, Jiawen; Li, S.; Wang, B.; Finkelman, R.B.

    2011-01-01

    Three hundred and six coal samples were taken from main coal mines of twenty-six provinces, autonomous regions, and municipalities in China, according to the resource distribution and coal-forming periods as well as the coal ranks and coal yields. Nitrogen was determined by using the Kjeldahl method at U. S. Geological Survey (USGS), which exhibit a normal frequency distribution. The nitrogen contents of over 90% Chinese coal vary from 0.52% to 1.41% and the average nitrogen content is recommended to be 0.98%. Nitrogen in coal exists primarily in organic form. There is a slight positive relationship between nitrogen content and coal ranking. ?? 2011 Science Press, Institute of Geochemistry, CAS and Springer Berlin Heidelberg.

  19. Coal marketing manual 1986

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    This manual presents information for the use of marketers, consumers, analysts and investors. The information is presented in a series of tables and figures. Statistics are given for: Australian export tonnages and average export values for 1978-1985; international pig iron production 1976 to 1985; and international crude steel production 1979 to 1985. Trends in Australian export tonnages and prices of coal are reviewed. Details of international loading and discharge ports are given, together with a historical summary of shipping freight-rates since 1982. Long term contract prices for thermal and coking coal to Japan are tabulated. A review of coal and standards is given, together with Australian standards for coal and coke. A section on coal quality is included containing information on consumer coal quality preferences and Australian and Overseas coal brands and qualities. Finally an index is given of contact details of Australian and Overseas exporting companies, government departments, and the Australian Coal Association.

  20. Coal worker's pneumoconiosis

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000130.htm Coal worker's pneumoconiosis To use the sharing features on this page, please enable JavaScript. Coal worker's pneumoconiosis (CWP) is a lung disease that ...

  1. Comprehensive study of rheological and surface properties of the selected slag system in the context of its internal structure

    Directory of Open Access Journals (Sweden)

    L. Řeháčková

    2016-10-01

    Full Text Available Rheological (dynamic viscosity, flow curves and surface properties (surface tension of real slag system were experimentally investigated. Measurements of dynamic viscosity were performed with use of the high-temperature viscometer Anton Paar FRS 1 600. The method of sessile drop was used for measurement of surface tension. Surface tension and dynamic viscosity were measured in the temperature interval from 1 200 to 1 600 °C. The structural characteristics of the selected samples were determined by X-ray diffraction (XRD. The samples for given analysis were prepared by quench cooling. Experimentally determined values of dynamic viscosity and surface tension were compared with the results of X-ray diffraction phase analysis.

  2. Utilization of brown coal in FRG power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kotler, V.R.

    1985-07-01

    FRG methods are studied for utilizing brown coal in view of the development of Kansk-Achinsk brown coal deposits. The use of brown coal in FRG power plants has increased from 15% in 1950- 1960 to 85% (total output) in 1982, providing 79.4 TWh of electrical energy. The remainder was used for briquetting, pulverization and breeze coke. In 1982 nearly 100 million tons of brown coal were burned by six large power stations (rated capacity 11,400 MW) to produce nearly 80 billion kWh of energy. Measures are discussed taken to reduce slagging and to remove excessive moisture content. Problems are analyzed associated with increased contamination of the atmosphere in areas with high population density (412/km/sup 2/) and cost of suppression is reviewed. According to available data, the cost of preventive measures taken by FRG, USA, Japan and the Netherlands is equal to 30% of the total cost of the energy. The most critical problem is suppression of sulfur dioxide, either by dry or wet scrubbers or by the addition of dry dolomite or lime to the furnace (75% of all SO/sub 2/ emissions in FRG comes from power stations). A method is described developed by RWE based on a series of distribution headers in the upper part of combustion chambers. At best, 70-80% reduction can be achieved. 14 references.

  3. Coal combustion by-products: A survey of use and disposal provisions

    International Nuclear Information System (INIS)

    Jagiella, D.M.

    1993-01-01

    Over 50% of all electricity in the United States is generated by the combustion of coal. Currently, coal fired power plants produce approximately 85 million to 100 million tons of coal combustion byproducts each year. The generation of these byproducts is expected to increase to 120 million tons by the year 2000, an increase of about 72% over 1984 levels. There are four basic types of byproducts produced by coal combustion - fly as, bottom ash, boiler slag, and flue gas desulfurization sludge (FGD), and are useful as engineering materials in a variety of applications. Fly ash represents nearly 75% of all ash wastes generated in the United States. Fly ash is a powder like substance with bonding properties. The properties of fly ash depend on the type of boiler utilized. The collected fly ash can be used to partially replace cement in concrete or the clay tit bricks or as part of nine reclamation. The technology for use of fly ash in cement concrete and road bases is well developed and has been practical for many years. The United States Environmental Protection Agency (USEPA) has recognized the applications of fly ash and promulgated a federal procurement guideline for the use of fly ash in cement and concrete. Although fly ash is the second most widely used waste product, much opportunity remains to expand the use of this product, In 1984, 80% of all fly ash was not recycled but rather disposed of, Ash particles that do not escape in flue gas as fly ash become bottom ash or boiler slag. Bottom ash and boiler slag settles on the bottom of the power plant's boiler. Bottom ash is a sand like substance which has some bonding capability. Depending on the type of boiler, tile bottom ash may be open-quotes dry bottom ashclose quotes or open-quotes wet bottom ashclose quotes, Wet bottom ash falls in a molten state into water

  4. Fording Canadian Coal Trust

    Energy Technology Data Exchange (ETDEWEB)

    Popowich, J.; Millos, R. [Elk Valley Coal Corporation, Calgary, AB (Canada)

    2004-07-01

    This is the first of five slide/overhead presentations presented at the Fording Canadian Coal Trust and Tech Cominco Ltd. investor day and mine tour. The Fording Canadian Coal Trust is described. The Trust's assets comprise six Elk Valley metallurgical coal mines and six wollastonite operations (in the NYCO Group). Trust structure, corporate responsibility, organizational structure, reserves and resources, management philosophy, operating strategies, steel market dynamics, coal market, production expansion, sales and distribution are outlined. 15 figs., 5 tabs.

  5. Coal. [1987 and 1989

    Energy Technology Data Exchange (ETDEWEB)

    1988-06-01

    Despite increases in recently negotiated coal prices in US dollar terms, unit export returns for Australian coal are expected to rise only marginally in 1988-89 due to the anticipated appreciation of the Australian dollar. Australian coal production is expected to recover in 1988-89, after falling in 1987-88. A table summarising coal statistics in 1985-87 is presented. 2 figs., 1 tab.

  6. Review biodepyritisation of coal

    Energy Technology Data Exchange (ETDEWEB)

    Acharya, C.; Sukla, L.B.; Misra, V.N. [Regional Research Lab., Orissa (India)

    2004-01-01

    This review provides a detailed summary of the recent and past research activities in the area of biodesulfurisation of coal. It provides information about microorganisms important for biodesulfurisation of coal, with the emphasis on Thiobacillus ferrooxidans. The review presents an insight into various methods of desulfurisation of coal combining physical and biological methods. Also, there are discussions on coal structure, distribution, mechanism and kinetics of pyrite oxidation and jarosite precipitation. Finally, areas requiring further research are identified.

  7. Coal dust symposium

    Energy Technology Data Exchange (ETDEWEB)

    1981-03-01

    This paper gives a report of the paper presented at the symposium held in Hanover on 9 and 10 February 1981. The topics include: the behaviour of dust and coal dust on combustion and explosion; a report on the accidents which occurred at the Laegerdorf cement works' coal crushing and drying plant; current safety requirements at coal crushing and drying plant; and coal crushing and drying. Four papers are individually abstracted. (In German)

  8. Coal world market

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    A brief analysis of major tendencies in the world market of coal is presented. It is pointed out that recent years, by and large, were favourable for the development of the world coal industry. Prices for coal (both for power-grade and coking one) in 1995 after many years of depressive state increased by nearly 20 % and reached a maximum of the last decade. International coal trading continues to grow and the tendency may persist in the mext two years

  9. Inorganic Constituents in Coal

    Directory of Open Access Journals (Sweden)

    Rađenović A.

    2006-02-01

    Full Text Available Coal contains not only organic matter but also small amounts of inorganic constituents. More thanone hundred different minerals and virtually every element in the periodic table have been foundin coal. Commonly found group minerals in coal are: major (quartz, pyrite, clays and carbonates,minor, and trace minerals. Coal includes a lot of elements of low mass fraction of the orderof w=0.01 or 0.001 %. They are trace elements connected with organic matter or minerals comprisedin coal. The fractions of trace elements usually decrease when the rank of coal increases.Fractions of the inorganic elements are different, depending on the coal bed and basin. A varietyof analytical methods and techniques can be used to determine the mass fractions, mode ofoccurrence, and distribution of organic constituents in coal. There are many different instrumentalmethods for analysis of coal and coal products but atomic absorption spectroscopy – AAS is theone most commonly used. Fraction and mode of occurrence are one of the main factors that haveinfluence on transformation and separation of inorganic constituents during coal conversion.Coal, as an important world energy source and component for non-fuels usage, will be continuouslyand widely used in the future due to its relatively abundant reserves. However, there is aconflict between the requirements for increased use of coal on the one hand and less pollution onthe other. It’s known that the environmental impacts, due to either coal mining or coal usage, canbe: air, water and land pollution. Although, minor components, inorganic constituents can exert asignificant influence on the economic value, utilization, and environmental impact of the coal.

  10. The NOXSO clean coal project

    Energy Technology Data Exchange (ETDEWEB)

    Black, J.B.; Woods, M.C.; Friedrich, J.J.; Browning, J.P. [NOXSO Corp., Bethel Park, PA (United States)

    1997-12-31

    The NOXSO Clean Coal Project will consist of designing, constructing, and operating a commercial-scale flue-gas cleanup system utilizing the NOXSO Process. The process is a waste-free, dry, post-combustion flue-gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from flue gas from coal-fired boilers. The NOXSO plant will be constructed at Alcoa Generating Corporation`s (AGC) Warrick Power Plant near Evansville, Indiana and will treat all the flue gas from the 150-MW Unit 2 boiler. The NOXSO plant is being designed to remove 98% of the SO{sub 2} and 75% of the NO{sub x} when the boiler is fired with 3.4 weight percent sulfur, southern-Indiana coal. The NOXSO plant by-product will be elemental sulfur. The elemental sulfur will be shipped to Olin Corporation`s Charleston, Tennessee facility for additional processing. As part of the project, a liquid SO{sub 2} plant has been constructed at this facility to convert the sulfur into liquid SO{sub 2}. The project utilizes a unique burn-in-oxygen process in which the elemental sulfur is oxidized to SO{sub 2} in a stream of compressed oxygen. The SO{sub 2} vapor will then be cooled and condensed. The burn-in-oxygen process is simpler and more environmentally friendly than conventional technologies. The liquid SO{sub 2} plant produces 99.99% pure SO{sub 2} for use at Olin`s facilities. The $82.8 million project is co-funded by the US Department of Energy (DOE) under Round III of the Clean Coal Technology program. The DOE manages the project through the Pittsburgh Energy Technology Center (PETC).

  11. Hard coal; Steinkohle

    Energy Technology Data Exchange (ETDEWEB)

    Loo, Kai van de; Sitte, Andreas-Peter [Gesamtverband Steinkohle e.V., Herne (Germany)

    2013-04-01

    The year 2012 benefited from a growth of the consumption of hard coal at the national level as well as at the international level. Worldwide, the hard coal still is the number one energy source for power generation. This leads to an increasing demand for power plant coal. In this year, the conversion of hard coal into electricity also increases in this year. In contrast to this, the demand for coking coal as well as for coke of the steel industry is still declining depending on the market conditions. The enhanced utilization of coal for the domestic power generation is due to the reduction of the nuclear power from a relatively bad year for wind power as well as reduced import prices and low CO{sub 2} prices. Both justify a significant price advantage for coal in comparison to the utilisation of natural gas in power plants. This was mainly due to the price erosion of the inexpensive US coal which partly was replaced by the expansion of shale gas on the domestic market. As a result of this, the inexpensive US coal looked for an outlet for sales in Europe. The domestic hard coal has continued the process of adaptation and phase-out as scheduled. Two further hard coal mines were decommissioned in the year 2012. RAG Aktiengesellschaft (Herne, Federal Republic of Germany) running the hard coal mining in this country begins with the preparations for the activities after the time of mining.

  12. Coal economics and taxation

    Energy Technology Data Exchange (ETDEWEB)

    1978-01-01

    These proceedings contain opening remarks, the luncheon and dinner addresses, list of delegates and the papers presented at the four sessions on Coal Mines cost money - for what.; Coal mines cost money - Where the money comes from; taxation and royalty policies; and the coal industry view on operating costs. Sixteen papers are abstracted separately.

  13. Design and operation of hybrid cooling towers

    International Nuclear Information System (INIS)

    Alt, W.

    1987-01-01

    The first hybrid cooling tower at a coal-fired power station with a waste heat output of 550 MW has been in operation since the middle of 1985. Experience during the construction stage and the initial period of operation has confirmed the correctness of the design standards and of the design itself and, of course, also offers a wealth of knowledge to be observed on future construction projects. A second cooling tower of similar design is being erected at the present time. This cooling tower serves a power station unit with 2500 MW of waste heat output. The programme for this cooling tower offers the possibility for all the accumulated and evaluated experience to be of influence both on the design and also on the method of operation. This paper reports on the details. (orig.) [de

  14. Accelerated Carbonation of Steel Slag Compacts: Development of High-Strength Construction Materials

    Energy Technology Data Exchange (ETDEWEB)

    Quaghebeur, Mieke; Nielsen, Peter, E-mail: peter.nielsen@vito.be; Horckmans, Liesbeth [Sustainable Materials Management, VITO, Mol (Belgium); Van Mechelen, Dirk [RECMIX bvba, Genk (Belgium)

    2015-12-17

    Mineral carbonation involves the capture and storage of carbon dioxide in carbonate minerals. Mineral carbonation presents opportunities for the recycling of steel slags and other alkaline residues that are currently landfilled. The Carbstone process was initially developed to transform non-hydraulic steel slags [stainless steel (SS) slag and basic oxygen furnace (BOF) slags] in high-quality construction materials. The process makes use of accelerated mineral carbonation by treating different types of steel slags with CO{sub 2} at elevated pressure (up to 2 MPa) and temperatures (20–140°C). For SS slags, raising the temperature from 20 to 140°C had a positive effect on the CO{sub 2} uptake, strength development, and the environmental properties (i.e., leaching of Cr and Mo) of the carbonated slag compacts. For BOF slags, raising the temperature was not beneficial for the carbonation process. Elevated CO{sub 2} pressure and CO{sub 2} concentration of the feed gas had a positive effect on the CO{sub 2} uptake and strength development for both types of steel slags. In addition, the compaction force had a positive effect on the strength development. The carbonates that are produced in situ during the carbonation reaction act as a binder, cementing the slag particles together. The carbonated compacts (Carbstones) have technical properties that are equivalent to conventional concrete products. An additional advantage is that the carbonated materials sequester 100–150 g CO{sub 2}/kg slag. The technology was developed on lab scale by the optimization of process parameters with regard to compressive strength development, CO{sub 2} uptake, and environmental properties of the carbonated construction materials. The Carbstone technology was validated using (semi-)industrial equipment and process conditions.

  15. Recycling of residual IGCC slags and their benefits as degreasers in ceramics.

    Science.gov (United States)

    Iglesias Martín, I; Acosta Echeverría, A; García-Romero, E

    2013-11-15

    This work studies the evolution of IGCC slag grains within a ceramic matrix fired at different temperatures to investigate the effect of using IGCC slag as a degreaser. Pressed ceramic specimens from two clay mixtures are used in this study. The M1 mixture is composed of standard clays, whereas the M2 mixture is composed of the same clay mixture as M1 mixture but contains 15% by weight IGCC slag. The amount of IGCC slag added coincides with the amount of slag typically used as a degreaser in the ceramic industry. Specimens are fired at 950 °C, 1000 °C, 1050 °C, 1100 °C and 1150 °C. The mineralogical composition and the IGCC slag grain shape within the ceramic matrix are determined by X-ray diffraction, polarized light microscopy and scanning electron microscopy. The results reveal that the surface of the slag grains is welded to the ceramic matrix while the quartz grains are separated, which causes increased water absorption and reduces the mechanical strength. IGCC slag, however, reduces water absorption. This behaviour is due to the softening temperature of the slag. This property is quite important from an industrial viewpoint because IGCC slag can serve as an alternative to traditional degreasing agents in the ceramic building industry. Additionally, using IGCC slag allows for the transformation of waste into a secondary raw material, thereby avoiding disposal at landfills; moreover, these industrial wastes are made inert and improve the properties of ceramics. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Evaluation of the use of steelmaking slag as an aggregate in concrete mix: A factorial design approach

    Directory of Open Access Journals (Sweden)

    Aljbour Salah H.

    2017-01-01

    Full Text Available Slag is investigated towards its potential use as an aggregate in concrete mix production. Full factorial design methodology is applied to study the effect of two process input variables, namely: slag as coarse aggregate and slag as medium aggregate on the properties of concrete mix. Additionally, the interaction between input variables is also examined. Incorporating steel slag aggregate in the concrete mix affected its compressive strength. Enhanced compressive strength concrete mix was obtained with 70 wt.% coarse slag aggregate and 70 wt.% medium slag aggregate. Under these proportions, the 28-days compressive strength was higher than the 28-days compressive strength of a concrete mix prepared from normal aggregate. Strong interaction effect exists between slag aggregate size on the compressive strength at 7-days curing. Lower compressive strength for the concrete mix might be obtained if improper proportions of mixed medium and coarse slag aggregate were employed.

  17. Dioxin emissions from coal combustion in domestic stove: Formation in the chimney and coal chlorine content influence

    Directory of Open Access Journals (Sweden)

    Paradiz Bostjan

    2015-01-01

    Full Text Available Combustion experiments conducted in domestic stove burning hard coal demonstrated a predominant influence of the coal chlorine content on the PCDD/F emissions, together with a pronounced effect of the flue gas temperature. PCDD/F concentrations of over 100 ng TEQ/m3, three orders of magnitude higher than in a modern waste incinerator, were measured in the flue gases of a domestic stove when combusting high chlorine coal (0.31 %. The PCDD/F concentrations in the flue gases dropped below 0,5 ng TEQ/m3, when low chlorine coal (0.07 % was used. When low chlorine coal was impregnated with NaCl to obtain 0.38 % chlorine content, the emission of the PCDD/Fs increased by two orders of magnitude. Pronounced nonlinearity of the PCDD/F concentrations related to chlorine content in the coal was observed. The combustion of the high chlorine coal yielded PCDD/F concentrations in flue gases one order of magnitude lower in a fan cooled chimney when compared to an insulated one, thus indicating formation in the chimney. The influence of flue gas temperature on the PCDD/F emissions was less pronounced when burning low chlorine coal. The predominant pathway of the PCDD/F emissions is via flue gases, 99 % of the TEQ in the case of the high chlorine coal for insulated chimney.

  18. Coal Combustion Products Extension Program

    Energy Technology Data Exchange (ETDEWEB)

    Tarunjit S. Butalia; William E. Wolfe

    2006-01-11

    This final project report presents the activities and accomplishments of the ''Coal Combustion Products Extension Program'' conducted at The Ohio State University from August 1, 2000 to June 30, 2005 to advance the beneficial uses of coal combustion products (CCPs) in highway and construction, mine reclamation, agricultural, and manufacturing sectors. The objective of this technology transfer/research program at The Ohio State University was to promote the increased use of Ohio CCPs (fly ash, FGD material, bottom ash, and boiler slag) in applications that are technically sound, environmentally benign, and commercially competitive. The project objective was accomplished by housing the CCP Extension Program within The Ohio State University College of Engineering with support from the university Extension Service and The Ohio State University Research Foundation. Dr. Tarunjit S. Butalia, an internationally reputed CCP expert and registered professional engineer, was the program coordinator. The program coordinator acted as liaison among CCP stakeholders in the state, produced information sheets, provided expertise in the field to those who desired it, sponsored and co-sponsored seminars, meetings, and speaking at these events, and generally worked to promote knowledge about the productive and proper application of CCPs as useful raw materials. The major accomplishments of the program were: (1) Increase in FGD material utilization rate from 8% in 1997 to more than 20% in 2005, and an increase in overall CCP utilization rate of 21% in 1997 to just under 30% in 2005 for the State of Ohio. (2) Recognition as a ''voice of trust'' among Ohio and national CCP stakeholders (particularly regulatory agencies). (3) Establishment of a national and international reputation, especially for the use of FGD materials and fly ash in construction applications. It is recommended that to increase Ohio's CCP utilization rate from 30% in 2005 to

  19. Rheology of fly ashes from coal and biomass co-combustion

    DEFF Research Database (Denmark)

    Arvelakis, Stelios; Frandsen, Flemming

    2010-01-01

    The presence of large amounts of alkali metals, chlorine and sulphur in most biomass fuels - compared to coal - can create serious ash-related problems such as deposition, agglomeration and/or corrosion. This paper discusses the viscosity characteristics of fly ash from the co-combustion of various...... coal/biomass blends in a pilot scale pf-boiler. The produced data provide information on the melting of the ash and its flow characteristics, as a function of temperature, which may be used to modify the temperature profile of the boiler in order to avoid slagging. Straw co-firing lowers the ash...... viscosity leading to higher stickiness of the ash particles. Wood co-firing has only minor effects, due to the composition of wood ash and the low percentage of wood in the coal/biomass blend....

  20. Self-scrubbing coal

    International Nuclear Information System (INIS)

    Kindig, J.K.

    1992-01-01

    More than 502 million tons - 65 percent of all coal shipped to utilities in 1990 - were above 1.2 pounds of sulfur dioxide per million Btu. Most of the coal, even though cleaned in conventional coal preparation plants, still does not meet the emission limitation the Clean Air Act Amendments mandate for the year 2000. To cope with this fact, most utilities plan to switch to low sulfur (western U.S. or Central Appalachian) coal or install scrubbers. Both solutions have serous drawbacks. Switching puts local miners out of work and weakens the economy in the utility's service territory. Scrubbing requires a major capital expenditure by the utility. Scrubbers also increase the operating complexity and costs of the generating station and produce yet another environmental problem, scrubber sludge. Employing three new cost-effective technologies developed by Customer Coals International (CCl), most non-compliance coals east of the Mississippi River can be brought into year-2000 compliance. The compliance approach employed, depends upon the characteristics of the raw coal. Three types of raw coal are differentiated, based upon the amount of organic sulfur in the coals and the ease (or difficultly) of liberating the pyrite. They are: Low organic sulfur content and pyrite that liberates easily. Moderate organic sulfur content and pyrite that liberates easily. High organic sulfur content or the pyrite liberates with difficulty. In this paper examples of each type of raw coal are presented below, and the compliance approach employed for each is described. The names of the beneficiated coal products produced from each type of raw coal give above are: Carefree Coal, Self-Scrubbing Coal and Dry-Scrubbing Coal

  1. COAL-FIRED UTILITY BOILERS: SOLVING ASH DEPOSITION PROBLEMS; TOPICAL

    International Nuclear Information System (INIS)

    Christopher J. Zygarlicke; Donald P. McCollor; Steven A. Benson; Jay R. Gunderson

    2001-01-01

    The accumulation of slagging and fouling ash deposits in utility boilers has been a source of aggravation for coal-fired boiler operators for over a century. Many new developments in analytical, modeling, and combustion testing methods in the past 20 years have made it possible to identify root causes of ash deposition. A concise and comprehensive guidelines document has been assembled for solving ash deposition as related to coal-fired utility boilers. While this report accurately captures the current state of knowledge in ash deposition, note that substantial research and development is under way to more completely understand and mitigate slagging and fouling. Thus, while comprehensive, this document carries the title ''interim,'' with the idea that future work will provide additional insight. Primary target audiences include utility operators and engineers who face plant inefficiencies and significant operational and maintenance costs that are associated with ash deposition problems. Pulverized and cyclone-fired coal boilers are addressed specifically, although many of the diagnostics and solutions apply to other boiler types. Logic diagrams, ash deposit types, and boiler symptoms of ash deposition are used to aid the user in identifying an ash deposition problem, diagnosing and verifying root causes, determining remedial measures to alleviate or eliminate the problem, and then monitoring the situation to verify that the problem has been solved. In addition to a step-by-step method for identifying and remediating ash deposition problems, this guideline document (Appendix A) provides descriptions of analytical techniques for diagnostic testing and gives extensive fundamental and practical literature references and addresses of organizations that can provide help in alleviating ash deposition problems

  2. Australian Coal Company Risk Factors: Coal and Oil Prices

    OpenAIRE

    M. Zahid Hasan; Ronald A. Ratti

    2014-01-01

    Examination of panel data on listed coal companies on the Australian exchange over January 1999 to February 2010 suggests that market return, interest rate premium, foreign exchange rate risk, and coal price returns are statistically significant in determining the excess return on coal companies’ stock. Coal price return and oil price return increases have statistically significant positive effects on coal company stock returns. A one per cent rise in coal price raises coal company returns ...

  3. Evaluation of the use of steelmaking slag as an aggregate in concrete mix: A factorial design approach

    OpenAIRE

    Aljbour Salah H.; Tarawneh Sultan A.; Al-Harahsheh Adnan M.

    2017-01-01

    Slag is investigated towards its potential use as an aggregate in concrete mix production. Full factorial design methodology is applied to study the effect of two process input variables, namely: slag as coarse aggregate and slag as medium aggregate on the properties of concrete mix. Additionally, the interaction between input variables is also examined. Incorporating steel slag aggregate in the concrete mix affected its compressive strength. Enhanced compressive strength concrete mix was obt...

  4. BARZAS DEPOSIT SAPROPELITE COALS: PROSPECTS OF INTEGRATED DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    L. V. Kuznetsova

    2018-03-01

    the enterprises for extraction of coal, semi-coking plant, boiler room, the chemical enterprise for processing of ash-slag from burning of waste of pyrolysis. The enterprise for receiving ore raw materials and construction materials are also among them. Summary. The organization of the main processes (from coal mining to commercial production within the framework of the energy chemical cluster will create an efficient, environmentally friendly and low-waste production. The consumer value of the obtained commodity products (resin, pyrogenetic water, fuel gas, thermal energy, ore concentrate and building materials will be much higher than the cost of raw high-ash coal.

  5. Coal Data: A reference

    International Nuclear Information System (INIS)

    1991-01-01

    The purpose of Coal Data: A Reference is to provide basic information on the mining and use of coal, an important source of energy in the United States. The report is written for a general audience. The goal is to cover basic material and strike a reasonable compromise between overly generalized statements and detailed analyses. The section ''Coal Terminology and Related Information'' provides additional information about terms mentioned in the text and introduces new terms. Topics covered are US coal deposits, resources and reserves, mining, production, employment and productivity, health and safety, preparation, transportation, supply and stocks, use, coal, the environment, and more. (VC)

  6. Cool snacks

    DEFF Research Database (Denmark)

    Grunert, Klaus G; Brock, Steen; Brunsø, Karen

    2016-01-01

    Young people snack and their snacking habits are not always healthy. We address the questions whether it is possible to develop a new snack product that adolescents will find attractive, even though it is based on ingredients as healthy as fruits and vegetables, and we argue that developing...... such a product requires an interdisciplinary effort where researchers with backgrounds in psychology, anthropology, media science, philosophy, sensory science and food science join forces. We present the COOL SNACKS project, where such a blend of competences was used first to obtain thorough insight into young...... people's snacking behaviour and then to develop and test new, healthier snacking solutions. These new snacking solutions were tested and found to be favourably accepted by young people. The paper therefore provides a proof of principle that the development of snacks that are both healthy and attractive...

  7. Cool visitors

    CERN Multimedia

    2006-01-01

    Pictured, from left to right: Tim Izo (saxophone, flute, guitar), Bobby Grant (tour manager), George Pajon (guitar). What do the LHC and a world-famous hip-hop group have in common? They are cool! On Saturday, 1st July, before their appearance at the Montreux Jazz Festival, three members of the 'Black Eyed Peas' came on a surprise visit to CERN, inspired by Dan Brown's Angels and Demons. At short notice, Connie Potter (Head of the ATLAS secretariat) organized a guided tour of ATLAS and the AD 'antimatter factory'. Still curious, lead vocalist Will.I.Am met CERN physicist Rolf Landua after the concert to ask many more questions on particles, CERN, and the origin of the Universe.

  8. The hydration of slag, part 1: reaction models for blended cement

    NARCIS (Netherlands)

    Chen, Wei; Brouwers, Jos

    2007-01-01

    Reaction models are proposed to quantify the hydration products and to determine the composition of C–S–H from alkali-activated slags (AAS). Products of the slag hydration are first summarized from observations in literature. The main hydration products include C–S–H, hydrotalcite, hydrogarnet, AFm

  9. Design of a continuous process setup for precipitated calcium carbonate production from steel converter slag.

    Science.gov (United States)

    Mattila, Hannu-Petteri; Zevenhoven, Ron

    2014-03-01

    A mineral carbonation process "slag2PCC" for carbon capture, utilization, and storage is discussed. Ca is extracted from steel slag by an ammonium salt solvent and carbonated with gaseous CO2 after the separation of the residual slag. The solvent is reused after regeneration. The effects of slag properties such as the content of free lime, fractions of Ca, Si, Fe, and V, particle size, and slag storage on the Ca extraction efficiency are studied. Small particles with a high free-lime content and minor fractions of Si and V are the most suitable. To limit the amount of impurities in the process, the slag-to-liquid ratio should remain below a certain value, which depends on the slag composition. Also, the design of a continuous test setup (total volume ∼75 L) is described, which enables quick process variations needed to adapt the system to the varying slag quality. Different precipitated calcium carbonate crystals (calcite and vaterite) are generated in different parts of the setup. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Behaviour of fibre reinforced concrete using steel slag coarse aggregate produced in Qatar

    Directory of Open Access Journals (Sweden)

    Alnahhal Wael

    2017-01-01

    Full Text Available The state of Qatar suffers from the shortage of natural resources needed for concrete production. Therefore, it is essential to investigate the feasibility of using by-product recycled materials as aggregates to maintain the concrete construction industry. Several types of recyclable materials are currently used in concrete. One of the potential resources of recycled concrete is steel slag. Knowing that Steel slag is the most significant solid waste generated by Qatar Steel Company in Qatar, replacing of natural coarse aggregate with steel slag aggregate will have a significant environmental and economic impact to the state of Qatar. This paper presents the compression and flexural test results of different concrete mixes made of steel slag coarse aggregate combined with a newly developed basalt chopped fibres. The parameters investigated included the volume fraction of the fibre used and the type of coarse aggregates (natural aggregates “Gabbro” and steel slag aggregates. Plain concrete specimens containing natural coarse aggregates and steel slag aggregates with no fibres added were also tested to serve as control. Test results showed that adding the basalt chopped fibres to the concrete mixes enhanced their flexural tensile strengths at different percentages. In addition, the compressive strength of concrete made with steel slag aggregate was higher than that made with natural gabbro aggregate. Test results clearly showed that steel slag aggregates can be used as sustainable and eco-friendly alternative materials in concrete structures.

  11. Treatment of metallurgical wastes : recovery of metal values from smelter slags by pressure oxidative leaching

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y.; Perederiy, I.; Papangelakis, V.G. [Toronto Univ., ON (Canada). Dept. of Chemical Engineering and Applied Chemistry

    2008-07-01

    Vast quantities of slag are produced and dumped as waste by-products during the production of base metals by smelting operations. These slags contain large amounts of valuable metals which lead to a decrease in metal yield and, combined with the entrapped sulphur, pose a danger to the environment. The dissolution of fayalite is important for the selective recovery of valuable metals and the cleanup of slags in high pressure oxidative leaching. The nature of base metals and iron in solidified slag must be investigated in order to understand the mechanism of the process. This paper discussed the application of powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM) for the characterization of a smelter slag microstructure. The study used leaching tests with the same smelter slag to measure and monitor the results of leaching, including metal extraction levels, the extent of iron dissolution as well as impurity contents. The paper provided information on the experiment with particular reference to slag leaching, chemical analysis, and characterization. It was concluded that slag consists of several solid phases with base metal sulfide and oxide droplets entrapped in the fayalite matrix or silica regions. Therefore, nickel, copper, cobalt, and zinc need to be exposed either chemically or mechanically to promote their recovery. 21 refs., 4 tabs., 5 figs.

  12. Substrate pH and butterfly bush response to dolomitic lime or steel slag amendment

    Science.gov (United States)

    Steel slag is a fertilizer amendment with a high concentration of calcium oxide, and thus capable of raising substrate pH similar to dolomitic lime. Steel slag, however, contains higher concentrations of some nutrients, such as iron, manganese, and silicon, compared to dolomitic lime. The objectiv...

  13. Industrial Tests to Modify Molten Copper Slag for Improvement of Copper Recovery

    Science.gov (United States)

    Guo, Zhengqi; Zhu, Deqing; Pan, Jian; Zhang, Feng; Yang, Congcong

    2018-04-01

    In this article, to improve the recovery of copper from copper slag by flotation process, industrial tests of the modification process involving addition of a composite additive into molten copper slag were conducted, and the modified slag was subjected to the flotation process to confirm the modification effect. The phase evolution of the slag in the modification process was revealed by thermodynamic calculations, x-ray diffraction, optical microscopy and scanning electron microscopy. The results show that more copper was transformed and enriched in copper sulfide phases. The magnetite content in the modified slag decreased, and that of "FeO" increased correspondingly, leading to a better fluidity of the molten slag, which improved the aggregation and growth of fine particles of the copper sulfide minerals. Closed-circuit flotation tests of the original and modified slags were conducted, and the results show that the copper recovery increased obviously from 69.15% to 73.38%, and the copper grade of concentrates was elevated slightly from 20.24% to 21.69%, further confirming that the industrial tests of the modification process were successful. Hence, the modification process has a bright future in industrial applications for enhancing the recovery of copper from the copper slag.

  14. Coal and public perceptions

    International Nuclear Information System (INIS)

    Porter, R.C.

    1993-01-01

    The Department of Energy's (DOE) clean coal outreach efforts are described. The reason why clean coal technology outreach must be an integral part of coal's future is discussed. It is important that we understand the significance of these advances in coal utilization not just in terms of of hardware but in terms of public perception. Four basic premises in the use of coal are presented. These are: (1) that coal is fundamentally important to this nation's future; (2) that, despite premise number 1, coal's future is by no means assured and that for the last 10 years, coal has been losing ground; (3) that coal's future hinges on the public understanding of the benefits of the public's acceptance of advanced clean coal technology; and (4) hat public acceptance of clean coal technology is not going to be achieved through a nationwide advertising program run by the Federal government or even by the private sector. It is going to be gained at the grassroots level one community at a time, one plant at a time, and one referendum at a time. The Federal government has neither the resources, the staff, nor the mandate to lead the charge in those debates. What is important is that the private sector step up to the plate as individual companies and an individual citizens working one-one-one at the community level, one customer, one civic club, and one town meeting at a time

  15. Indonesian coal export potential

    International Nuclear Information System (INIS)

    Millsteed, Ch.; Jolly, L.; Stuart, R.

    1993-01-01

    Indonesia's coal mining sector is expanding rapidly. Much of the increase in coal production since the mid-1980s has been exported. Indonesian coal mining companies have large expansion programs and continuing strong export growth is projected for the remainder of the 1990s. The low mining costs of indonesian coal, together with proximity to Asian markets, mean that Indonesia is well placed to compete strongly with other thermal coal exporters and win market share in the large and expanding thermal coal market in Asia. However, there is significant uncertainty about the likely future level of Indonesia's exportable surplus of coal. The government's planned expansion in coal fired power generation could constrain export growth, while the ability of producers to meet projected output levels is uncertain. The purpose in this article is to review coal supply and demand developments in Indonesia and, taking account of the key determining factors, to estimate the level of coal exports from Indonesia to the year 2000. This time frame has been chosen because all currently committed mine developments are expected to be on stream by 2000 and because it is difficult to project domestic demand for coal beyond that year. 29 refs., 8 tabs., 7 figs

  16. Coal; Le charbon

    Energy Technology Data Exchange (ETDEWEB)

    Teissie, J.; Bourgogne, D. de; Bautin, F. [TotalFinaElf, La Defense, 92 - Courbevoie (France)

    2001-12-15

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

  17. Washability of Australian coals

    Energy Technology Data Exchange (ETDEWEB)

    Whitmore, R L

    1979-06-01

    Australian coals tend to be young in geological age and high in ash by world standards; preparation of the coal before marketing is almost universal. On the basis of float and sink data from 39 locations in the eastern Australian coalfields, the coals are place in four categories representing increasing difficulty in their washability characteristics. These seem to be related neither to the geological age nor the geographical position of the deposit and Hunter Valley coals, for example, span all categories. The influence of crushing on the washability of Australian coals is briefly considered and from limited data it is concluded to be appreciably smaller than for British or North American coals. A strategy for the float and sink analysis of Australian coals is proposed and the influence of washability characteristics on current trends in the selection of separating processes for coking and steaming products is discussed.

  18. Supplying Fe from molten coal ash to revive kelp community

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, K.; Yamamoto, M.; Sadakata, M. [University of Tokyo, Tokyo (Japan)

    2006-02-15

    The phenomenon of a kelp-dominated community changing to a crust-dominated community, which is called 'barren-ground', is progressing in the world, and causing serious social problems in coastal areas. Among several suggested causes of 'barren-ground', we focused on the lack of Fe in seawater. Kelp needs more than 200 nM of Fe to keep its community. However there are the areas where the concentration of Fe is less than 1 nM, and the lack of Fe leads to the 'barren-ground.' Coal ash is one of the appropriate materials to compensate the lack of Fe for the kelp growth, because the coal ash is a waste from the coal combustion process and contains more than 5 wt% of Fe. The rate of Fe elution from coal fly ash to water can be increased by 20 times after melting in Ar atmosphere, because 39 wt% of the Fe(III) of coal fly ash was reduced to Fe(II). Additionally molten ash from the IGCC (integrated coal gasification combined cycle) furnace in a reducing atmosphere and one from a melting furnace pilot plant in an oxidizing atmosphere were examined. Each molten ash was classified into two groups; cooled rapidly with water and cooled slowly without water. The flux of Fe elution from rapidly cooled IGCC molten ash was the highest; 9.4 x 10{sup -6} g m{sup -2} d{sup -1}. It was noted that the coal ash melted in a reducing atmosphere could elute Fe effectively, and the dissolution of the molten ash itself controlled the rate of Fe elution in the case of rapidly cooled molten ash.

  19. Artificial intelligence-based computer modeling tools for controlling slag foaming in electric arc furnaces

    Science.gov (United States)

    Wilson, Eric Lee

    Due to increased competition in a world economy, steel companies are currently interested in developing techniques that will allow for the improvement of the steelmaking process, either by increasing output efficiency or by improving the quality of their product, or both. Slag foaming is one practice that has been shown to contribute to both these goals. However, slag foaming is highly dynamic and difficult to model or control. This dissertation describes an effort to use artificial intelligence-based tools (genetic algorithms, fuzzy logic, and neural networks) to both model and control the slag foaming process. Specifically, a neural network is trained and tested on slag foaming data provided by a steel plant. This neural network model is then controlled by a fuzzy logic controller, which in turn is optimized by a genetic algorithm. This tuned controller is then installed at a steel plant and given control be a more efficient slag foaming controller than what was previously used by the steel plant.

  20. Heavy metal recovery from electric arc furnace steel slag by using hydrochloric acid leaching

    Science.gov (United States)

    Wei, Lim Jin; Haan, Ong Teng; Shean Yaw, Thomas Choong; Chuah Abdullah, Luqman; Razak, Mus'ab Abdul; Cionita, Tezara; Toudehdehghan, Abdolreza

    2018-03-01

    Electric Arc Furnace steel slag (EAFS) is the waste produced in steelmaking industry. Environmental problem such as pollution will occur when dumping the steel slag waste into the landfill. These steel slags have properties that are suitable for various applications such as water treatment and wastewater. The objective of this study is to develop efficient and economical chlorination route for EAFS extraction by using leaching process. Various parameters such as concentration of hydrochloric acid, particle size of steel slag, reaction time and reaction temperature are investigated to determine the optimum conditions. As a result, the dissolution rate can be determined by changing the parameters, such as concentration of hydrochloric acid, particle size of steel slag, reaction time and reaction temperature. The optimum conditions for dissolution rates for the leaching process is at 3.0 M hydrochloric acid, particle size of 1.18 mm, reaction time of 2.5 hour and the temperature of 90°C.

  1. Research on the compressive strength of basic magnesium salts and cyanide slag solidified body

    Science.gov (United States)

    Tu, Yubo; Han, Peiwei; Ye, Shufeng; Wei, Lianqi; Zhang, Xiaomeng; Fu, Guoyan; Yu, Bo

    2018-02-01

    The solidification of cyanide slag by using basic magnesium salts could reduce pollution and protect the environment. Experiments were carried out to investigate the effects of age, mixing amount of cyanide slag, water cement ratio and molar ratio of MgO to MgSO4 on the compressive strength of basic magnesium salts and cyanide slag solidified body in the present paper. It was found that compressive strength of solidified body increased with the increase of age, and decreased with the increase of mixing amount of cyanide slag and water cement ratio. The molar ratio of MgO to MgSO4 should be controlled in the range from 9 to 11 when the mixing amount of cyanide slag was larger than 80 mass%.

  2. Strength and Drying Shrinkage of Alkali-Activated Slag Paste and Mortar

    Directory of Open Access Journals (Sweden)

    Mao-chieh Chi

    2012-01-01

    Full Text Available The aim of this study is to investigate the strengths and drying shrinkage of alkali-activated slag paste and mortar. Compressive strength, tensile strength, and drying shrinkage of alkali-activated slag paste and mortar were measured with various liquid/slag ratios, sand/slag ratios, curing ages, and curing temperatures. Experimental results show that the higher compressive strength and tensile strength have been observed in the higher curing temperature. At the age of 56 days, AAS mortars show higher compressive strength than Portland cement mortars and AAS mortars with liquid/slag ratio of 0.54 have the highest tensile strength in all AAS mortars. In addition, AAS pastes of the drying shrinkage are higher than AAS mortars. Meanwhile, higher drying shrinkage was observed in AAS mortars than that observed comparable Portland cement mortars.

  3. Fabrication of slag-glass composite with controlled porosity

    Directory of Open Access Journals (Sweden)

    Ranko Adziski

    2008-06-01

    Full Text Available The preparation and performance of porous ceramics made from waste materials were investigated. Slag from thermal electrical plant Kakanj (Bosnia and Herzegovina with defined granulations: (0.500÷0.250 mm; (0.250÷0.125 mm; (0.125÷0.063 mm; (0.063÷0.045 mm and 20/10 wt.% of the waste TV screen glass with a granulation <0.063 mm were used for obtaining slag-glass composites with controlled porosity. The one produced from the slag powder fraction (0.125÷0.063 mm and 20 wt.% TV screen glass, sintered at 950°C/2h, was considered as the optimal. This system possesses open porosity of 26.8±1.0%, and interconnected pores with the size of 250–400 μm. The values of E-modulus and bending strength of this composite were 10.6±0.6 GPa and 45.7±0.7 MPa, respectively. The coefficient of thermal expansion was 8.47·10-6/°C. The mass loss in 0.1M HCl solution after 30 days was 1.2 wt.%. The permeability and the form coefficient of the porous composite were K0=0.12 Da and C0=4.53·105 m-1, respectively. The porous composite shows great potential to be used as filters, diffusers for water aeration, dust collectors, acoustic absorbers, etc.

  4. Process for hydrogenating coal and coal solvents

    Energy Technology Data Exchange (ETDEWEB)

    Shridharani, K.G.; Tarrer, A.R.

    1983-02-15

    A novel process is described for the hydrogenation of coal by the hydrogenation of a solvent for the coal in which the hydrogenation of the coal solvent is conducted in the presence of a solvent hydrogenation catalyst of increased activity, wherein the hydrogenation catalyst is produced by reacting ferric oxide with hydrogen sulfide at a temperature range of 260/sup 0/ C to 315/sup 0/ C in an inert atmosphere to produce an iron sulfide hydrogenation catalyst for the solvent. Optimally, the reaction temperature is 275/sup 0/ C. Alternately, the reaction can be conducted in a hydrogen atmosphere at 350/sup 0/ C.

  5. Process for hydrogenating coal and coal solvents

    Science.gov (United States)

    Tarrer, Arthur R.; Shridharani, Ketan G.

    1983-01-01

    A novel process is described for the hydrogenation of coal by the hydrogenation of a solvent for the coal in which the hydrogenation of the coal solvent is conducted in the presence of a solvent hydrogenation catalyst of increased activity, wherein the hydrogenation catalyst is produced by reacting ferric oxide with hydrogen sulfide at a temperature range of 260.degree. C. to 315.degree. C. in an inert atmosphere to produce an iron sulfide hydrogenation catalyst for the solvent. Optimally, the reaction temperature is 275.degree. C. Alternately, the reaction can be conducted in a hydrogen atmosphere at 350.degree. C.

  6. Coal use and coal technology study (KIS)

    International Nuclear Information System (INIS)

    Kram, T.; Okken, P.A.; Gerbers, D.; Lako, P.; Rouw, M.; Tiemersma, D.N.

    1991-11-01

    The title study aims to assess the possible role for coal in the Netherlands energy system in the first decades of the next century and the part new coal conversion technologies will play under various conditions. The conditions considered relate to (sectoral) energy demand derived from national scenarios in an international context, to energy prices, to environmental constraints (acidification, solid waste management and disposal) and to the future role for nuclear power production. Targets for reduction of greenhouse gas emissions are not explicitly included, but resulting CO 2 emissions are calculated for each variant case. The part that coal can play in the Dutch energy supply is calculated and analyzed by means

  7. Crystallization Kinetics of Precipitating Calcium from Yellow Phosphorus Slag Lixivium

    Directory of Open Access Journals (Sweden)

    Li, G. -B.

    2014-11-01

    Full Text Available The crystallization dynamic parameters of calcium sulphate were determined in the course of the precipitation conversion process of calcium in lixivium. The crystallization dynamic equations of calcium sulphate were achieved by multiple linear regression. The study results indicate that CaSO4 · 2 H2O crystal nucleation-growth kinetics equation in nitric acid leaching liquid of yellow phosphorus slag at room temperature is expressed by B0 = 2.904 · 1011 · G0.83 · MT 0.167.

  8. ESR hollows molten metal/slag interface detection

    International Nuclear Information System (INIS)

    Harris, B.; Klein, H.J.

    1983-01-01

    A system for detecting the location of a molten metal/slag interface during the casting of electroslag remelted hollows includes a gamma ray radiation source and a scintillation counter. The source and counter reside outside the casting mould and are held in fixed spatial relationships with respect to one another and with respect to the mandrel. The radiation from the source is directed chordally through the mould and through the annular casting zone, defined between the sidewalls of the upwardly driven mandrel and the mould without contacting said mandrel. The counter provides an electrical signal responsive to the rate of radiation events detected thereby. (author)

  9. Alkali-activated blast furnace slag-zeolite cements and concretes

    International Nuclear Information System (INIS)

    Rakhimov, R.; Rakhimova, N.

    2012-01-01

    The aim of this work has been the study of alkali-activated slag-zeolite cements and concretes based on them. Various compositions have been tested and some characteristics such as the compressive strength have been measured versus zeolite additions. A table lists the specific surface area and particle size distributions of different cements. The conclusions of the study are the following. First, alkali-activated slag cements and concretes based on them are effective for immobilization of radioactive wastes and the production of building structures, designed for high radiation load. Secondly, zeolite-containing mineral additions are able to increase the immobilization capacity and radiation resistance of alkali-activated blast furnace slag cements and concretes. Thirdly, the efficiency of different zeolite-containing additions - 10% to increase alkali-activated blast furnace slag-zeolite cement strength was established. It is with alkaline components of water-glass, sodium carbonate, sodium sulphate. Fourth, the effective way of introducing zeolite additions in alkali-activated blast furnace slag-zeolite cement is inter-grinding of the slag and addition. Increase in strength of alkali-activated blast furnace slag-zeolite cement stone is 40% higher than that of the stone of a mixture of separately milled components. Fifth, Alkali-activated blast furnace slag-zeolite cements with zeolite-containing additions with a compressive strength of 10.1 to 140 MPa; alkali-activated blast furnace slag-zeolite cements mortars with compressive strength from 35.2 to 97.7 MPa; alkali-activated blast furnace slag-zeolite cements concretes with compressive strength up to 84.5 MPa and frost resistant up to 800 cycles were obtained

  10. Evaluation of copper slag to catalyze advanced oxidation processes for the removal of phenol in water

    Energy Technology Data Exchange (ETDEWEB)

    Huanosta-Gutierrez, T. [Instituto de Ingenieria, Coordinacion de Ingenieria Ambiental, Universidad Nacional Autonoma de Mexico, Cd. Universitaria, Coyoacan 04510, Mexico, D.F. (Mexico); Dantas, Renato F., E-mail: falcao@angel.qui.ub.es [Departament d' Enginyeria Quimica, Universitat de Barcelona, Marti i Franques 1, 08028 Barcelona (Spain); Ramirez-Zamora, R.M. [Instituto de Ingenieria, Coordinacion de Ingenieria Ambiental, Universidad Nacional Autonoma de Mexico, Cd. Universitaria, Coyoacan 04510, Mexico, D.F. (Mexico); Esplugas, S. [Departament d' Enginyeria Quimica, Universitat de Barcelona, Marti i Franques 1, 08028 Barcelona (Spain)

    2012-04-30

    Highlights: Black-Right-Pointing-Pointer We evaluate the use of an industrial residue (copper slag) as catalyst in water treatment. Black-Right-Pointing-Pointer The copper slag was effective to remove organic pollutants (phenol) from water. Black-Right-Pointing-Pointer During experimentation, Cu and Fe leaching were not higher than the acceptable levels. Black-Right-Pointing-Pointer Slag/H{sub 2}O{sub 2}/UV and slag/H{sub 2}O{sub 2} treatments promoted biodegradability increment of the contaminated water. Black-Right-Pointing-Pointer The control of the reaction time would minimize the environmental impact of the produced effluents in terms of acute toxicity. - Abstract: The aim of this work was to evaluate the use of copper slag to catalyze phenol degradation in water by advanced oxidation processes (AOPs). Copper slag was tested in combination with H{sub 2}O{sub 2} (slag/H{sub 2}O{sub 2}) and H{sub 2}O{sub 2}/UV (slag/H{sub 2}O{sub 2}/UV). The studied methods promoted the complete photocatalytic degradation of phenol. Besides, they were able to reduce about 50% the TOC content in the samples. Slag/H{sub 2}O{sub 2}/UV and slag/H{sub 2}O{sub 2} treatments have favored biodegradability increment along the reaction time. Nevertheless, the irradiated method achieved higher values of the biodegradability indicator (BOD{sub 5}/TOC). The toxicity assessment indicated the formation of more toxic compounds in both treatments. However, the control of the reaction time would minimize the environmental impact of the effluents.

  11. Visualisation and quantification of heavy metal accessibility in smelter slags: The influence of morphology on availability.

    Science.gov (United States)

    Morrison, Anthony L; Swierczek, Zofia; Gulson, Brian L

    2016-03-01

    The Imperial Smelting Furnace (ISF) for producing lead and zinc simultaneously has operated on four continents and in eleven countries from the 1950's. One of the process changes that the ISF introduced was the production of a finely granulated slag waste. Although this slag contained significant amounts of residual lead (Pb) and zinc (Zn), because of its glassy nature it was considered environmentally benign. From the Cockle Creek smelter near Boolaroo at the northern end of Lake Macquarie, NSW, Australia, it is estimated that around 2.1 million tonnes of the fine slag was distributed into the community and most remains where it was originally utilised. Residual tonnages of slag of this magnitude are common worldwide wherever the ISF operated. Studies of base metal smelting slags have concluded that mineralogical and morphological characteristics of the slag play a critical role in moderating environmental release of toxic elements. Scanning electron microscopy (SEM) and microanalysis of the ISF slags has shown that the Pb and associated elements are present as discrete nodules (∼6-22 μm) in the slag and that they are not associated with Zn which is contained in the glass slag phase. Using an automated SEM and analysis technique (QEMSCAN(®)) to "map" the mineralogical structure of the particles, it was possible to quantitatively determine the degree of access infiltrating fluids might have to the reaction surface of the Pb phases. The level of access decreases with increasing particle size, but in even the largest sized particles (-3350 + 2000 μm) nearly 80% of the Pb-containing phases were totally or partially accessible. These results provide evidence that the toxic elements in the slags are not contained by the glassy phase and will be vulnerable to leaching over time depending on their individual phase reactivity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Influence of slag chemistry on the hydration of alkali-activated blast-furnace slag - Part I: Effect of MgO

    International Nuclear Information System (INIS)

    Ben Haha, M.; Lothenbach, B.; Le Saout, G.; Winnefeld, F.

    2011-01-01

    The hydration and the microstructure of three alkali activated slags (AAS) with MgO contents between 8 and 13 wt.% are investigated. The slags were hydrated in the presence of two different alkaline activators, NaOH and Na 2 SiO 3 .5H 2 O (WG). Higher MgO content of the slag resulted in a faster reaction and higher compressive strengths during the first days. The formation of C(- A)-S-H and of a hydrotalcite-like phase was observed in all samples by X-ray diffraction (XRD), thermal analysis (TGA) and scanning electron microscopy (SEM) techniques. Increasing the MgO content of the slag from 8 to 13% increased the amount of hydrotalcite and lowered the Al uptake by C-S-H resulting in 9% higher volume of the hydrates and a 50 to 80% increase of the compressive strength after 28 days and longer for WG activated slag pastes. For NaOH activated slags only a slight increase of the compressive strength was measured.

  13. Impact of steel slag on the ammonium adsorption by zeolite and a new configuration of zeolite-steel slag substrate for constructed wetlands.

    Science.gov (United States)

    Shi, Pengbo; Jiang, Yingbo; Zhu, Hongtao; Sun, Dezhi

    2017-07-01

    The CaO dissolution from slag, as well as the effects of influencing parameters (i.e. pH and Ca 2+ concentration) on the ammonium adsorption onto zeolite, was systematically studied in this paper. Modeling results of Ca 2+ and OH - release from slag indicated that pseudo-second-order reaction had a better fitness than pseudo-first-order reaction. Changing pH value from 7 to 12 resulted in a drastic reduction of the ammonium adsorption capacity on zeolite, from the peak adsorption capacity at pH 7. High Ca 2+ concentration in solution also inhibited the adsorption of ammonium onto zeolite. There are two proposed mechanisms for steel slag inhibiting the ammonium adsorption capacity of zeolite. On the one hand, OH - released from steel slag can react with ammonium ions to produce the molecular form of ammonia (NH 3 ·H 2 O), which would cause the dissociation of NH 4 + from zeolite. On the other hand, Ca 2+ could replace the NH 4 + ions to adhere onto the surface of zeolite. An innovative substrate filling configuration with zeolite placed upstream of the steel slag was then proposed to eliminate the disadvantageous effects of steel slag. Experimental results showed that this novel filling configuration was superior to two other filling configurations in terms of ammonium removal.

  14. Divertor cooling device

    International Nuclear Information System (INIS)

    Nakayama, Tadakazu; Hayashi, Katsumi; Handa, Hiroyuki

    1993-01-01

    Cooling water for a divertor cooling system cools the divertor, thereafter, passes through pipelines connecting the exit pipelines of the divertor cooling system and the inlet pipelines of a blanket cooling system and is introduced to the blanket cooling system in a vacuum vessel. It undergoes emission of neutrons, and cooling water in the divertor cooling system containing a great amount of N-16 which is generated by radioactivation of O-16 is introduced to the blanket cooling system in the vacuum vessel by way of pipelines, and after cooling, passes through exit pipelines of the blanket cooling system and is introduced to the outside of the vacuum vessel. Radiation of N-16 in the cooling water is decayed sufficiently with passage of time during cooling of the blanket, thereby enabling to decrease the amount of shielding materials such as facilities and pipelines, and ensure spaces. (N.H.)

  15. Screening of candidate corrosion resistant materials for coal combustion environments -- Volume 4. Final report, January 31, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Boss, D.E.

    1997-12-31

    The development of a silicon carbide heat exchanger is a critical step in the development of the Externally-Fired Combined Cycle (EFCC) power system. SiC is the only material that provides the necessary combination of resistance to creep, thermal shock, and oxidation. While the SiC structural materials provide the thermomechanical and thermophysical properties needed for an efficient system, the mechanical properties of the SiC tubes are severely degraded through corrosion by the coal combustion products. To obtain the necessary service life of thousands of hours at temperature, a protective coating is needed that is stable with both the SiC tube and the coal combustion products, resists erosion from the particle laden gas stream, is thermal-shock resistant, adheres to SiC during repeated thermal shocks (start-up, process upsets, shut-down), and allows the EFCC system to be cost competitive. The candidate protective materials identified in a previous effort were screened for their stability to the EFCC combustion environment. Bulk samples of each of the eleven candidate materials were prepared, and exposed to coal slag for 100 hours at 1,370 C under flowing air. After exposure the samples were mounted, polished, and examined via x-ray diffraction, energy dispersive spectroscopy, and scanning electron microscopy. In general, the alumina-based materials behaved well, with comparable corrosion depths in all five samples. Magnesium chromite formed a series of reaction products with the slag, which included an alumina-rich region. These reaction products may act as a diffusion barrier to slow further reaction between the magnesium chromite and the slag and prove to be a protective coating. As for the other materials; calcium titanate failed catastrophically, the CS-50 exhibited extension microstructural and compositional changes, and zirconium titanate, barium zironate, and yttrium chromite all showed evidence of dissolution with the slag.

  16. Heating up the gas cooling market

    International Nuclear Information System (INIS)

    Watt, G.

    2001-01-01

    Gas cooling is an exciting technology with a potentially bright future. It comprises the production of cooling (and heating) in buildings and industry, by substituting environmentally-friendlier natural gas or LPG over predominantly coal-fired electricity in air conditioning equipment. There are currently four established technologies using gas to provide cooling energy or conditioned air. These are: absorption, both direct gas-fired and utilising hot water or steam; gas engine driven vapour compression (GED); cogeneration, with absorption cooling driven by recovered heat; and desiccant systems. The emergence of gas cooling technologies has been, and remains, one of evolution rather than revolution. However, further development of the technology has had a revolutionary effect on the performance, reliability and consumer acceptability of gas cooling products. Developments from world-renowned manufacturers such as York, Hitachi, Robur and Thermax have produced a range of absorption equipment variously offering: the use of 100 percent environmentally-friendly refrigerants, with zero global warming potential; the ideal utilisation of waste heat from cogeneration systems; a reduction in electrical distribution and stand-by generation capacity; long product life expectancy; far less noise and vibration; performance efficiency maintained down to about 20 percent of load capacity; and highly automated and low-cost maintenance. It is expected that hybrid systems, that is a mixture of gas and electric cooling technologies, will dominate the future market, reflecting the uncertainty in the electricity market and the prospects of stable future gas prices

  17. WORKSHOP: Beam cooling

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    Cooling - the control of unruly particles to provide well-behaved beams - has become a major new tool in accelerator physics. The main approaches of electron cooling pioneered by Gersh Budker at Novosibirsk and stochastic cooling by Simon van der Meer at CERN, are now complemented by additional ideas, such as laser cooling of ions and ionization cooling of muons

  18. Clean coal technologies

    International Nuclear Information System (INIS)

    Aslanyan, G.S.

    1993-01-01

    According to the World Energy Council (WEC), at the beginning of the next century three main energy sources - coal, nuclear power and oil will have equal share in the world's total energy supply. This forecast is also valid for the USSR which possesses more than 40% of the world's coal resources and continuously increases its coal production (more than 700 million tons of coal are processed annually in the USSR). The stringent environmental regulations, coupled with the tendency to increase the use of coal are the reasons for developing different concepts for clean coal utilization. In this paper, the potential efficiency and environmental performance of different clean coal production cycles are considered, including technologies for coal clean-up at the pre-combustion stage, advanced clean combustion methods and flue gas cleaning systems. Integrated systems, such as combined gas-steam cycle and the pressurized fluidized bed boiler combined cycle, are also discussed. The Soviet National R and D program is studying new methods for coal utilization with high environmental performance. In this context, some basic research activities in the field of clean coal technology in the USSR are considered. Development of an efficient vortex combustor, a pressurized fluidized bed gasifier, advanced gas cleaning methods based on E-beam irradiation and plasma discharge, as well as new catalytic system, are are presented. In addition, implementation of technological innovations for retrofitting and re powering of existing power plants is discussed. (author)

  19. Coal prices rise

    International Nuclear Information System (INIS)

    McLean, A.

    2001-01-01

    Coking and semi hard coking coal price agreements had been reached, but, strangely enough, the reaching of common ground on semi soft coking coal, ultra low volatile coal and thermal coal seemed some way off. More of this phenomenon later, but suffice to say that, traditionally, the semi soft and thermal coal prices have fallen into place as soon as the hard, or prime, coking coal prices have been determined. The rise and rise of the popularity of the ultra low volatile coals has seen demand for this type of coal grow almost exponentially. Perhaps one of the most interesting facets of the coking coal settlements announced to date is that the deals appear almost to have been preordained. The extraordinary thing is that the preordination has been at the prescience of the sellers. Traditionally, coking coal price fixing has been the prerogative of the Japanese Steel Mills (JSM) cartel (Nippon, NKK, Kawasaki, Kobe and Sumitomo) who presented a united front to a somewhat disorganised force of predominantly Australian and Canadian sellers. However, by the time JFY 2001 had come round, the rules of the game had changed

  20. South Blackwater Coal`s maintenance program

    Energy Technology Data Exchange (ETDEWEB)

    Nash, J. [South Blackwater Coal Limited, Blackwater, Qld. (Australia)

    1998-09-01

    The South Blackwater operation consists of two opencut mining areas and two underground mines (Laleham and Kenmure) near Blackwater in central Queensland, all of which supply coal to a central coal preparation plant. South Blackwater Coal Ltd. recently developed a maintenance improvement programme, described in this article. The programme involved implementation systems of key performance indicators (KPIs), benchmaking, condition monitoring, work planning and control, failure analysis and maintenance audit. Some improvements became almost immediately apparent, others were quite gradual. Major results included: improved availability (and reliability) of all opencast fleets, improvements in rear dump availability; reduced maintenance man-hours for opencast fleets; and increased availability of the coal handling and preparation plant. The paper is an edited version of that presented at the `Maintenance in mining conference` 16-19 March 1998, held in Bali, Indonesia. 4 figs., 2 photos.