Journal articles: 'Scrap metals'

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Baah, Owusu Panin Kwame. "Innovative Use of the Pointillism Technique for the Production of Scrap Metal Mural Art of Kofi Annan for Environmental Sustainability." Journal of Innovations in Science and Technology 1, no. 1 (April 27, 2023): 60–78. http://dx.doi.org/10.60129/jinces.v1i1.00523.

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Scrap metals have been an environmental nuisance blocking the pathways of water and leading to various forms of environmental pollution at Anloga in the Kumasi Metropolis of Ghana. This scrap metal art project was aimed at creatively reusing and re-purposing scrap metals from various construction, dump sites and households for the creation of a metal artwork as a step in reviving scrap metal art for environmental sustainability. Over the years, murals have been made using various techniques in painting and sculpture. The studio-based research design that employs the qualitative descriptive method was used for this project. The project adopted the concept of pointillism whereby tiny dots in various pure colours are used in creating an artwork that is appreciated when viewed from a distance. We replicated this concept by representing the dots with metal domes from scrap metals in producing an innovative commemorative metal mural of the former UN General Secretary, Kofi Annan. The researchers employed participant observation and used photographs to collect the data by carefully studying the various scrap metals that were available for the project and by utilizing most metal working techniques. It was very necessary to carry on this project to revive scrap metal art in Ghana which is gradually dying out. The study revealed that recycling and melting of metal scraps should be done in kilns and furnaces rather than in open hearth processes for best results. The study recommends the exploration of other methods of doming in the future for much efficiency. Also, the study recommends the exploration of other fine art techniques and media using various scrap metals for artistic production.

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Abdulsalam, S., A. D. Bajoga, and H. A. Dala. "Impact of Metals Scrap Yard on the Presence of some Heavy Metals Concentration within Gombe Metropolis, Gombe State, Nigeria, using Atomic Absorption Spectrometry." Nigerian Journal of Physics 33, no. 2 (June 30, 2024): 115–22. http://dx.doi.org/10.62292/njp.v33i2.2024.246.

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The Metal scrap yards play a crucial role in the recycling and reuse of metals, contributing significantly to the economy and conservation of natural resources. However, the processing and storage of metal scraps can lead to the release of heavy metals such as lead, chromium and cadmium, into the environment. The presence of heavy metals in metal scrap yards poses a significant risk to nearby communities, workers and the environment, also causing air and water pollution, soil contamination, and health problem. Study of impact of metals scrap yard on the presence some of some heavy metals in soil samples was done using Atomic Absorption Spectrometer (AAS). Top soil sample were collected from eight metals scrap yards and their corresponding control areas. One gram (1 g) each of the soil samples was digested and then heated slowly and steadily, the solution appears colorless. The samples were allowed to cool and ready for analysis. The result obtained was, the mean elemental concentration element was of the order ofMn (41.022±41.202)> Cu (4.416±4.274) >Pb (2.685±1.399) > Mg (0.500±10.122) > Cr (0.460±0.187) > Cd (0.125±0.027) > Co (0.04±0.000)> Ni (0.000±0.000). The comparison of the elemental concentration of the heavy metals of (Mn, Mg, Cu, Pd, Cr, Cd, Co and Ni) in the study area ware shows the metal scrap yard has impact in the presence of heavy metals in soil. In addition, the Contamination factor (CF), and Pollution load index (PLI) of each trace element in soil of the study area and their respective control area were all < 1 which implies that they all have low contamination factors, less polluted and low contaminated.

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Wędrychowicz, Maciej, Andrzej Piotrowicz, Tomasz Skrzekut, Piotr Noga, and Adam Bydalek. "Recovery of Non-Ferrous Metals from PCBs Scrap by Liquation from Lead." Materials 15, no. 6 (March 11, 2022): 2089. http://dx.doi.org/10.3390/ma15062089.

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This article presents the results of research on the recycling of non-ferrous metals from PCB scrap using melting in metallic lead. The idea of this process is to dissolve (transfer) metals from PCB scrap in lead, and then liquation them by cooling the lead-metals alloy. PCB scrap was crushed and then melted into liquid lead. The lead after process was then poured into the casting mold and its chemical composition was examined. Among the various metals in the PCB scrap, copper and tin in particular are dissolved in lead. The more scrap dissolved in lead, the higher the concentration of copper and tin in the alloy. The highest obtained concentration of copper in lead were about 2.2 wt.%, and for tin about 0.8 wt.%.

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Mysik, V. F. "Scrap processing - a look into the future." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information, no. 10 (November 9, 2018): 61–66. http://dx.doi.org/10.32339/0135-5910-2018-10-61-66.

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Saturation of depreciation scrap by non-ferrous metals and different nonmetallic materials complicates its utilization for steel smelting, particularly a quality one. For possible avoiding receipt of nonferrous metals into steel melt it is necessary to provide more careful scrap segregation by application of state-of-the-art scrap processing equipment.Main requirement to the steel scrap processing equipment formulated. It must provide uniformity of burden materials fraction content and separation of extraneousmaterials and nonferrous metals.Existing methods of scrap preparation, including different methods of crushing, packaging, separation and other considered. It was shown, that shredder aggregates are most perspective equipment for scrap refining from harmful impurities and its preparation to smelting. Shredder processing of scrap provides the smelting facilities by homogeneous burden of high bulk density.The presented material has a discussion character, aiming at attracting attention of specialists to the problem of scrap processing industry development.

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Wu, Liushun, Kunlong Liu, Haiqing Mei, Guangda Bao, Yun Zhou, and Haichuan Wang. "Thermodynamics Analysis and Pilot Study of Reusing Medium and High Alloy Steel Scrap Using Induction Melting and Electroslag Remelting Process." Metals 12, no. 6 (May 30, 2022): 944. http://dx.doi.org/10.3390/met12060944.

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The annual cumulative quantity of high and medium alloy steel scrap has exceeded 10 million tons. Using the traditional smelting process involving electric arc refining in a smelting furnace for these scraps causes high percentages of alloy losses, which decreases the value of the alloy steel scrap and poses environmental threats. Existing studies have rarely focused on separate smelting of the scrap and oxidation behaviors of the alloying elements. Therefore, this study proposes an induction melting and electroslag remelting scheme to process the scrap. Based on this scheme, the effects of the temperature, oxygen content, and element contents on the recovery percentages of the alloying elements were investigated using pilot experiment and thermodynamic analysis. The experimental results showed that the alloying elements (tungsten, chromium, nickel, molybdenum, and vanadium) exhibited recovery percentages of 97.36%, 94.62%, 97.63%, 95.09%, and 89.49%, respectively; furthermore, the impurity content did not increase during smelting. The thermodynamic analysis indicated that an increase in carbon content improved the oxidation resistance of the alloying elements except for nickel, whereas the increases in the contents of oxygen and alloying elements increase their oxidation. Steam partial pressure and air suction dramatically increase the concentrations of nitrogen, hydrogen and oxygen. This scheme is an alternative for smelting medium and high alloy steel scrap, and the thermodynamic analysis provides a theoretical understanding of the oxidation behaviors of the alloying elements in the steel scrap and the control of impurity.

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Hoffmann, James E. "Recovering precious metals from electronic scrap." JOM 44, no. 7 (July 1992): 43–48. http://dx.doi.org/10.1007/bf03222275.

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Garino, Robert J. "Scrap convention spotlights metals commodity markets." JOM 45, no. 11 (November 1993): 12–14. http://dx.doi.org/10.1007/bf03222479.

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Shao, Hui Ping, Tao Lin, Ji Luo, and Zhi Meng Guo. "Separation and Recycling Non-Magnetic Metals from the Shredded Automobiles Scrap with Magnetic Fluids." Advanced Materials Research 233-235 (May 2011): 470–75. http://dx.doi.org/10.4028/www.scientific.net/amr.233-235.470.

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It is important to separate the nonmagnetic metals from shredded automobiles scraps efficiently. The research relates in general to the separation of non-magnetic metals automatically on the basis of the different density of the magnetic fluids in a magnetic field. A water-based magnetic fluid was prepared with a chemical coprecipitation method by using ultrasonic in dispersing process. The magnetic field system was design and simulated by a finite element analysis software package, ANSYS 8.1. Separation tests were performed on the mixtures of aluminum, zinc, copper and lead with various scrap size and shape using the water-based magnetic fluids.

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EBILOMA, Innah Peter, and Nemile Victoria SHAIBU. "Assessment of Heavy Metal Residues in Hides of animals Singed with Tyres, and Public Health Implications Associated with such Practice in Lokoja Metropolis." International Journal of Latest Technology in Engineering, Management & Applied Science XII, no. IV (2023): 18–29. http://dx.doi.org/10.51583/ijltemas.2023.12403.

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The safety of food has been an issue of concern in developing countries like Nigeria where the processing method can pose some environmental health challenge. The use of scrap automobile tires to singe meat has been reported to possess some toxic materials that can pose health challenge to humans. Hence, this study was conducted to determine the concentration of heavy metals in meat singed with fire wood and scrap tires in Lokoja, Nigeria. Samples of cattle hides singed with firewood and scrap tires were collected from four (4) different abattoirs and analyzed for the concentration of Cu, Pb, Fe and Zn using Atomic Absorption Spectrophotometry. There was significant increase in the concentration of Cu, Zn and Pb of the cattle hides singed with firewood and scrap tires when compared to the unsinged. The concentration of heavy metals for firewood singed cattle hide is within recommended Maximum Permissible Levels (MPLs) of the European Commission Regulations while the concentration of scrap tires is above the recommended Maximum Permissible Levels (MPLs) of the European Commission Regulations for Cu, Zn and Fe. Though there was increase in the concentration of Fe it is within the recommended Maximum Permissible Levels. The presence of heavy metals concentration above the permissible levels in cattle hides singed with scrap tires makes it unsafe for human consumption hence safer method should be adopted by the abattoirs.

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BRISTOW, C. A., A. J. SIDERY, and H. SUTTON. "METAL ECONOMICS SCRAP RECLAMATION, SECONDARY METALS, AND SUBSTITUTE METALS." Journal of the American Society for Naval Engineers 64, no. 3 (March 18, 2009): 644–64. http://dx.doi.org/10.1111/j.1559-3584.1952.tb02994.x.

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11

Nicol, Stuart, Benjamin Hogg, Oscar Mendoza, and Stanko Nikolic. "Extraction and Recovery of Critical Metals from Electronic Waste Using ISASMELT™ Technology." Processes 11, no. 4 (March 27, 2023): 1012. http://dx.doi.org/10.3390/pr11041012.

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Electronic goods are a major consumer of many critical metals, including copper, nickel, tin, zinc, lead, and precious metals. The processing of end-of-life electronic equipment (E-Scrap) is becoming increasingly important to maintain the supply of the critical metals required globally, and to reduce environmental pollution. Currently, the dominant route for E-Scrap processing is pyrometallurgical processing, with the first stage of processing being reductive smelting to produce a black copper and a ‘clean’ discard slag. The management of the slag in this first step is central to the success of the E-Scrap recycling process. The E-Scrap ISASMELT™ furnace has a highly turbulent bath, providing conditions that generate high rates of zinc fuming and allow a wide range of operable slag conditions. This enables efficient E-Scrap smelting to occur, whilst overcoming the challenges associated with alternative technologies. Operable slag compositions and high zinc fuming are heavily influenced by kinetic processes, with piloting critical to understanding the performance of this process. ISASMELT™ pilot tests were performed, with a wide range of fluxing targets tested to confirm these benefits. The testing demonstrated that high levels of zinc fuming (>80%) are obtained in the E-Scrap ISASMELT™ furnace, decreasing the iron and silica flux additions required to manage the detrimental viscosity effects of zinc in the slag. In addition, it was demonstrated that slags containing high concentrations of alumina (>10 wt%) are operable in an ISASMELT™ furnace. The ISASMELT™ technology was demonstrated to be the only E-Scrap furnace technology able to produce a ‘clean’ discard slag with low concentrations of zinc and minimal fluxing requirements.

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Okabe, Toru H., and Takanari Ouchi. "(Invited) Uip-Grade Recycling of Titanium Using Molten Salts." ECS Meeting Abstracts MA2023-01, no. 21 (August 28, 2023): 1521. http://dx.doi.org/10.1149/ma2023-01211521mtgabs.

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With the increasing demand for Ti, the amount of Ti scrap is expected to increase. Hence, a new process to efficiently remove oxygen in Ti directly from Ti scrap should be developed to recycle Ti scrap. However, it is difficult to remove oxygen directly from solid Ti, and no effective deoxidation method for Ti scrap has been developed on an industrial scale. In this study, we developed new techniques to remove dissolved oxygen directly from Ti through thermochemical or electrochemical reactions using rare earth metals and/or molten salts. Based on the thermodynamic analysis and experimental verifications, we found that it is possible to remove oxygen in Ti and Ti alloys below 100 mass ppm level directly from high-oxygen-containing metals. This technology is expected to be a new process to remove oxygen directly and efficiently from Ti scrap. Furthermore, the proposed deoxidation technique can be applied to a new smelting process of Ti based on the direct reduction of Ti from oxide feeds.

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13

Kruskopf, Ari, and Lauri Holappa. "Scrap melting model for steel converter founded on interfacial solid/liquid phenomena." Metallurgical Research & Technology 115, no. 2 (December 5, 2017): 201. http://dx.doi.org/10.1051/metal/2017091.

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The primary goal in steel converter operation is the removal of carbon from the hot metal. This is achieved by blowing oxygen into the melt. The oxidation of carbon produces a lot of heat. To avoid too high temperatures in the melt cold scrap (recycled steel) is charged into the converter. The melting rate is affected by heat and carbon mass transfer. A process model for steel converter is in development. This model is divided into several modules, which are fluid dynamics, heat- and mass-transfer, scrap melting and chemical reactions. This article focuses on the development of the scrap melting module. A numerical model for calculating temperature and carbon concentration in the melt is presented. The melt model is connected with the solid scrap model via solid/liquid interface. The interface model can take into account solidification of iron melt, melting of solidified layer, a situation without such phase changes, and scrap melting. The aim is to predict the melting rate of the scrap including the properties of the hot metal. The model is tested by calculating the melting rates for different scrap thicknesses. All of the stages in the interface model were taking place in the test calculations.

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Zarraa, Mahmoud A. "Adsorption Equilibria of Single-Component and Multi-Component Metal Ions on to Scrap Rubber." Adsorption Science & Technology 16, no. 6 (June 1998): 493–502. http://dx.doi.org/10.1177/026361749801600607.

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The ability of scrap rubber to adsorb the three metal ions, copper, cadmium and zinc, in single-component and multi-component mixtures in aqueous solutions has been studied. A comparison has been made between the single-component saturation uptake and the multi-component uptakes. The experimental results were fitted to the Langmuir, Freundlich and Redlich–Peterson isotherms. The correlation coefficients obtained from plotting these isotherms gave a measure of the conformity of the data to a linear trend and corresponded to a perfect fit. The isotherms indicated a competitive uptake, with copper being preferentially adsorbed by scrap rubber in multi-component solutions. The capacity of scrap rubber for the single-component metals was in the order: Cd > Cu > Zn. On the other hand, the order of preference of scrap rubber for metals in multi-component mixtures was: Cu > Cd > Zn.

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Koltygin, A. V., V. E. Bazhenov, A. I. Bazlov, T. A. Bazlova, and V. D. Belov. "Effect of scrap using in charge on the microstructure and properties of ZhS6U nickel-based superalloy. Part 2. Structure analysis and mechanical properties of ZhS6U prepared with scrap." Izvestiya. Ferrous Metallurgy 62, no. 7 (August 22, 2019): 525–30. http://dx.doi.org/10.17073/0368-0797-2019-7-525-530.

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The second part of the article considers influence of the scrap amount on structure and mechanical properties of ZhS6U-VI nickelbased superalloy. As the use of scrap is associated with the possibility of alloy contamination by nonmetallic inclusions and loss of alloying elements, the influence of scrap on alloy structure and mechanical properties is in great importance. The samples with diameter of 12 mm were melted in a vacuum arc furnace and were casted into a copper mold from the virgin ZhS6U-VI alloy without scrap and from alloys with 50 % and 100 % of scrap. The alloys structures were investigated using optical microscopy on etched metallographic sections that were cut from the samples’ cross-sections. The studies were carried out on the as-cast samples and the samples after solution heat treatment for 4 hours at 1210 °C. The slightly higher nonmetallic inclusions content were observed in the structure of the alloy melted with scrap in comparison with virgin alloy melted without scrap. For the sample that was melted from 100 % of scrap the inclusions secure level is 3 (ASTM E 45-97) with an average size of inclusions of 28.4 ± 0.2 μm. Herewith the presence of single large inclusions with a size of not more than 70 microns was noted. However, it has no effect on the alloy mechanical properties. Mechanical properties after heat treatment (ultimate strength (UTS) = 1090 – 1100 МPа and elongation (El) = 9 – 11 %) were obtained on the samples melted using 50 and 100 % of scrap and fully correspond to the TU1-92-177-91 standard for ZhS6U-VI nickel-base superalloy. During solidification most of the large nonmetallic inclusions are concentrated under casting surface, which makes their machining difficult. Because of that the use of 100 % scrap without its preliminary processing is not recommended. Acceptable results were achieved when the 50 % of scrap was used.

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Willner, J., A. Fornalczyk, J. Cebulski, and K. Janiszewski. "Preliminary Studies on Simultaneous Recovery of Precious Metals from Different Waste Materials by Pyrometallurgical Method." Archives of Metallurgy and Materials 59, no. 2 (June 1, 2014): 801–4. http://dx.doi.org/10.2478/amm-2014-0136.

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Abstract Automotive catalytic converters have a limited life time, after which the catalyst must be replaced or regenerated. The spent catalytic converters contain small amount of precious metals. Recovery of these metals is essential for environmental and economic reasons. The waste electronic equipment is also an attractive source for recovery of precious metals. Precious metals in electronic scraps are concentrated mainly in printed circuits and integrated circuits - so generally in elements that are the most diverse in their composition. Material heterogeneity of these elements is the reason why there is no universal method for processing this type of scrap. Methods used in the world for recovery of precious metals from spent auto catalytic coverters and electronic wastes by pyrometallurgical and hydrometallurgical methods were mentioned in this paper. The results of simultaneous melting of electronic waste with spent automotive catalysts were presented. The printed circuit boards were used as the carrier and as a source of copper. The precious metals present in the catalyst were collected in copper.

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Sum, Elaine Y. L. "The recovery of metals from electronic scrap." JOM 43, no. 4 (April 1991): 53–61. http://dx.doi.org/10.1007/bf03220549.

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Ilyas, Sadia, Chi Ruan, H. N. Bhatti, M. A. Ghauri, and M. A. Anwar. "Column bioleaching of metals from electronic scrap." Hydrometallurgy 101, no. 3-4 (March 2010): 135–40. http://dx.doi.org/10.1016/j.hydromet.2009.12.007.

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Turner, Ray. "SCRAP METALS INDUSTRY PERSPECTIVE ON RADIOACTIVE MATERIALS." Health Physics 91, no. 5 (November 2006): 489–93. http://dx.doi.org/10.1097/01.hp.0000236781.15424.4a.

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Ilyas, Sadia, and Jae-chun Lee. "Fungal leaching of metals from electronic scrap." Mining, Metallurgy & Exploration 30, no. 3 (August 2013): 151–56. http://dx.doi.org/10.1007/bf03402261.

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Birat, J. P., D. Huin, X. Le Coq, J. L. Roth, P. Russo, F. Lernière, and G. Moriamez. "Scrap : quality, preparation and pretreatment. Present and future." Revue de Métallurgie 92, no. 4 (April 1995): 477–586. http://dx.doi.org/10.1051/metal/199592040477.

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Scrap is increasingly used as a raw material in the steel industry in response to the generation of large quantities of scrap in industrialized countries. This means that scrap is becoming an industrial product, which will be processed more and more by effective preparation equipment and which should be controlled for quality in terms of iron content, level in tramp elements and density following methods and standards under development.

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Koltygin, A. V., V. E. Bazhenov, A. I. Bazlov, T. A. Bazlova, and V. D. Belov. "EFFECT OF SCRAP USING IN CHARGE ON THE STRUCTURE AND PROPERTIES OF ZhS6U NICKEL-BASED SUPERALLOY. PART 1. MICROSTRUCTURE ANALYSIS AND PHASE COMPOSITION OF ZhS6U ALLOY PREPARED WITH SCRAP." Izvestiya. Ferrous Metallurgy 62, no. 5 (June 19, 2019): 360–65. http://dx.doi.org/10.17073/0368-0797-2019-5-360-365.

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Expensive nickel superalloys are used for manufacture of cast blades of gas turbine engine (GTE). However, for the blades only a small amount of alloy was used and the remainder is used for gating system. Therefore, the most proportion of alloy after casting is a scrap, the use of which as raw material for blades production significantly reduces their cost. However, the use of scrap is associated with some risks: the possibility of alloy contamination by nonmetallic inclusions and loss of alloying elements. So, the investigation of a scrap usage effect on the blades properties is very important. In the first part of article the influence of the scrap amount on the microstructure and phase composition of the ZhS6U-VI nickel-base superalloy were examined. The GTE blades samples, fully produced from the scrap of ZhS6U-VI superalloy by investment casting were investigated. The scrap before using was cleaned from contaminations and ceramic mold remains. Samples were cut from blade dowetail and gating system near dowetail. In addition, cylindrical samples that were casted into the copper mold from the virgin alloy ZhS6U-VI without the scrap and from alloys with 50 % and 100 % of scrap were researched. The alloys microstructures were investigated using scanning electron microscopy and optical microscopy. The phase’s identification was carried out using the energy-dispersive X-ray spectroscopy (EDS) and the calculations of phase composition were made by Thermo-Calc software and literature data about phases in nickel-based superalloys. Content of alloying elements (except carbon) was measured by EDS analysis. The studies were carried out on the samples as-casted and annealed for 4 hours at 1210 °C. It is shown that the use of scrap does not fundamentally change the alloy phase composition at both during vacuum induction melting and vacuum arc melting.

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Li, Yifeng, Xunpeng Qin, Zhenyuan Zhang, and Huanyu Dong. "A robust identification method for nonferrous metal scraps based on deep learning and superpixel optimization." Waste Management & Research: The Journal for a Sustainable Circular Economy 39, no. 4 (January 26, 2021): 573–83. http://dx.doi.org/10.1177/0734242x20987884.

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End-of-life vehicles (ELVs) provide a particularly potent source of supply for metals. Hence, the recycling and sorting techniques for ferrous and nonferrous metal scraps from ELVs significantly increase metal resource utilization. However, different kinds of nonferrous metal scraps, such as aluminium (Al) and copper (Cu), are not further automatically classified due to the lack of proper techniques. The purpose of this study is to propose an identification method for different nonferrous metal scraps, facilitate the further separation of nonferrous metal scraps, achieve better management of recycled metal resources and increase sustainability. A convolutional neural network (CNN) and SEEDS (superpixels extracted via energy-driven sampling) were adopted in this study. To build the classifier, 80 training images of randomly chosen Al and Cu scraps were taken, and some practical methods were proposed, including training patch generation with SEEDS, image data augmentation and automatic labelling methods for enormous training data. To obtain more accurate results, SEEDS was also used to optimize the coarse results obtained from the pretrained CNN model. Five indicators were adopted to evaluate the final identification results. Furthermore, 15 test samples concerning different classification environments were tested through the proposed model, and it performed well under all of the employed evaluation indexes, with an average precision of 0.98. The results demonstrate that the proposed model is robust for metal scrap identification, which can be expanded to a complex industrial environment, and it presents new possibilities for highly accurate automatic nonferrous metal scrap classification.

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Hu, Xiao Ying, Xiao Chun Peng, Yang Zheng, and Yan Yu Wu. "Study on Index System for Graded and Classified Management of Enterprises Importing Scrap Metal." Advanced Materials Research 878 (January 2014): 879–85. http://dx.doi.org/10.4028/www.scientific.net/amr.878.879.

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Studying the status quo of the management and technology of the enterprises processing and utilizing the imported scrap metals, this paper identifies the environmental risks of such enterprises and constructs a index system for graded and classified management of enterprises importing scrap metals, which includes seven criterion layers, namely raw material hazard index (S1), product index (S2), site index (S3), production process and equipment index (S4), pollution prevention and control index (S5), environmental management index (S6) and corporate compliance index (S7), and 22 indexes. The paper also calculates the weight of each index with analytic hierarchy process.

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Voraberger, Bernhard, Gerald Wimmer, Uxia Dieguez Salgado, Erich Wimmer, Krzysztof Pastucha, and Alexander Fleischanderl. "Green LD (BOF) Steelmaking—Reduced CO2 Emissions via Increased Scrap Rate." Metals 12, no. 3 (March 10, 2022): 466. http://dx.doi.org/10.3390/met12030466.

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The basic oxygen furnace (BOF) is the dominating primary steelmaking process. It is an autothermal process where hot metal and scrap are used as charging materials. The decarbonization and transformation of integrated BOF steelmaking will be the most important challenge in the coming years. Steel scrap is a charge material without new CO2 emissions, whose availability is expected to grow significantly and will play a key role in this decarbonization process. Several solutions have been developed by Primetals Technologies to provide additional energy for processing higher scrap rates in integrated BOF steelmaking. Such solutions include simple upgrade packages installed on existing converters such as process models for heat optimization, post-combustion, and scrap preheating lances. For higher scrap rates from 30% to 50%, a combination blowing converter and JET converter is required to provide sufficient mixing during scrap melting and the highest heat transfer from the increased post-combustion. Hybrid EAF–BOF operation and limitations regarding scrap quality also need to be considered for the transformation of steelmaking. Scrap sorting and processing can be a solution to reduce residual levels in crude steel for high scrap rates. Based on reference plant data, the CO2 reduction potential of the presented solution versus the effort and complexity of implementation is compared.

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Strogonov, Konstantin V., and Andrey A. Chaymelov. "Modeling the High-Temperature Heating of Scrap Metals." Vestnik MEI 6 (2019): 58–63. http://dx.doi.org/10.24160/1993-6982-2019-6-58-63.

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Perkins, F. M. "THE FOUNDRY USE OF NON-FERROUS SCRAP METALS." Journal of the American Society for Naval Engineers 27, no. 1 (March 18, 2009): 127–44. http://dx.doi.org/10.1111/j.1559-3584.1915.tb00375.x.

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Karklit, A. K., V. M. Lobov, and S. Yu Kovaleva. "Refractory scrap from cement and nonferrous metals industries." Refractories 33, no. 5-6 (May 1992): 269–71. http://dx.doi.org/10.1007/bf01290255.

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Zhuang, Shenglei, Dongping Zhan, Taotao Wang, Peng Li, and Yongkun Yang. "Influence of Oxy-Fuel Lance Parameters on the Scrap Pre-Heating Temperature in the Hot Metal Ladle." Metals 13, no. 5 (April 25, 2023): 847. http://dx.doi.org/10.3390/met13050847.

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As one of the vital ways to improve the converter heat balance and increase the scrap ratio, scrap pre-heating technology has attracted much attention from researchers. The aim of this paper is to reveal the effect of the oxy-fuel lance parameters on the temperature field, flow field, and scrap pre-heating temperature in the ladle by means of numerical simulations. For this, a three-dimensional mathematical model containing the turbulence model, the porous medium heat balance model, and other models has been developed. The research results show that the rational and correct choice of gas flow rate, lance position, and nozzle angle has an important influence on the temperature field and the average scrap temperature. When the gas flow rate increases, the internal annular combustion zone of the scrap gradually expands, the cold zone at the bottom of the scrap continues to decrease, and the average scrap temperature keeps increasing. When the gas flow rate is 5000 m3/h, and the average scrap temperature reaches 1197 K, the pre-heating time is 9.98 min. Lowering the oxy-fuel lance position helps to reduce the cold zone at the bottom of the scrap and increases the average temperature in the cold zone. Reasonable selection of the nozzle angle is conducive to improving the uniformity of the flow field. When the angle of the nozzle is 15°, the gas circulation zone is the largest, and the time to reach an average scrap temperature of 1197 K is the shortest.

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Ibraheem, Jathwa A. "SITE ASSESSMENT GUIDANCE A CASE STUDY (OUIREEJ SCRAP YARD)." Journal of Engineering 15, no. 2 (June 1, 2009): 3840–54. http://dx.doi.org/10.31026/j.eng.2009.02.22.

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Scrap metal export is currently one of the few thriving industries in Iraq. Looters and legitimate operators are together effectively demolishing many of the old industrial facilities in order to retrieve the metal contained in buildings, processes and storage equipments and vehicles. The mixing of civilian and military scrapping operations such as that occurring at Ouireej is exacerbating the problem. The situation is particularly difficult for Iraq, given the rapid growth of the scrap industry and the lack of security. In view of the current difficulties, the focus was on practical short to medium term improvements such as controlling access to sites, land use zoning, licensing and export controls. The wholesale reform of the scrap metal industry to improve environmental practices, whilst desirable, is also probably not feasible in the short to medium term. The remediation of working scrap sites, such as Ouireej is also probably unfeasible at present. Laboratory analysis of shallowsoil detected contamination by PCBs, mineral oil and heavy metals, principally copper, lead, antimony and Zinc. The detected levels of all contaminants were relatively low. But PCB contamination was relatively widespread, being detected in eight soil samples with a maximum concentration of 23 μg/kg. Laboratory analysis of rainwater ponds on the site indicated marginal contamination by heavy metals and mineral oils

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Kim, Chan-Mi, Peyala Dharmaiah, Hyo-Seob Kim, Jar-Myung Koo, Jae-Sik Yoon, Hyun-Seon Hong, and Soon-Jik Hong. "Effect of Acid Dissolution Conditions on Recovery of Valuable Metals from Used Plasma Display Panel Scrap." Archives of Metallurgy and Materials 62, no. 2 (June 1, 2017): 1173–77. http://dx.doi.org/10.1515/amm-2017-0172.

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AbstractThe objective of this particular study was to recover valuable metals from waste plasma display panels using high energy ball milling with subsequent acid dissolution. Dissolution of milled (PDP) powder was studied in HCl, HNO3, and H2SO4acidic solutions. The effects of dissolution acid, temperature, time, and PDP scrap powder to acid ratio on the leaching process were investigated and the most favorable conditions were found: (1) valuable metals (In, Ag, Mg) were recovered from PDP powder in a mixture of concentrated hydrochloric acid (HCl:H2O = 50:50); (2) the optimal dissolution temperature and time for the valuable metals were found to be 60°C and 30 min, respectively; (3) the ideal PDP scrap powder to acid solution ratio was found to be 1:10. The proposed method was applied to the recovery of magnesium, silver, and indium with satisfactory results.

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Parrés, F., J. E. Crespo, A. Nadal, A. Macias-Garcia, and E. M. Cuerda-Correa. "On the Thermal Characterization of Fibers Prepared by Cryogenic Grinding of Scrap Tires." Materials Science Forum 636-637 (January 2010): 1421–27. http://dx.doi.org/10.4028/www.scientific.net/msf.636-637.1421.

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The importance of recovering and valorising the residues generated by industrialized societies is mainly due to the environmental impact that such residues may cause. In this connection, scrap tires constitute a major source of pollution. In the recent years large amounts of scrap tires have been recycled in order to recover the metals contained in this residue. Tires have also been grinded and the small particles produced have found different applications. In addition to metals and rubber particles, reinforcing fibers are also produced in the recycling process of scrap tires. As a previous step for the valorisation of this third constituent of waste tires, a characterization of such fibers is strongly recommended. Thermal analysis techniques make it possible to identify the fibers through the thermal transitions that may take place. Usually, such transitions result mainly in cotton and rayon. Furthermore, the combination of pyrolysis, gas chromatography and mass spectrometry techniques corroborates the identification of several compounds derived from the decomposition of the fibers as well as some materials used in the preparation of tires.

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Brandl, Helmut, Stefan Lehmann, and Mohammad A. Faramarzi. "Mobilization of Silver, Gold, and Platinum from Solid Materials by HCN-Forming Microorganisms." Advanced Materials Research 20-21 (July 2007): 50–53. http://dx.doi.org/10.4028/www.scientific.net/amr.20-21.50.

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Cyanogenic Chromobacterium violaceum, Pseudomonas fluorescens, and P. plecoglossicida were able to mobilize silver, gold and platinum when grown in the presence of various metal-containing solids such as powdered platinum, platinum-containing automobile catalytic converters, powdered silver, or gold-containing electronic scrap. Five percent of silver was mobilized from powdered jewelry scrap as dicyanoargentate after one day, although 96% was mobilized when non-biological cyanide leaching was applied. Dicyanoargentate proved to inhibit growth at concentrations >20 mg/L. Gold was microbially solubilized from electronic scrap (shredded printed circuit boards). Maximum dicyanoaurate concentration corresponded to a 68.5% dissolution of the total gold added. Additionally, cyanide-complexed copper was detected during treatment of electronic scrap due to its high copper content of approximately 100 g/kg scrap. Small amounts of platinum were mobilized from pure platinum powder after 10 days. The process proved to be very slow. In summary, all findings demonstrate the potential of microbial mobilization of metals as cyanide complex from solid materials and represent a novel type of microbial metal mobilization which might find industrial application.

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Barragán-Gutiérrez, Iván Ernesto, Alfonso López-Díaz, and Wolfgang Krumm. "Synthetic fuel production from shredded scrap waste." Revista Facultad de Ingeniería 26, no. 44 (January 25, 2017): 133. http://dx.doi.org/10.19053/01211129.v26.n44.2017.5784.

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This technological innovation project involved material identification, and design, installation, implementation, and evaluation of a pilot plant with capacity of 10 t per batch to recover materials and produce synthetic fuels (oil, syngas and solid) from shredded scrap waste. The results showed the proper way to separate materials (metals, and organic and inert compounds), and to perform the pyrolysis process to produce gas, oil, and coke as synthetic fuels from organic waste. The process started with the physicochemical characterization of the waste, followed by the selection of separation, sorting and processing technologies, and the definition of pyrolysis process parameters. Finally, the synthetic fuels were characterized, and uses for the furnace billet, ladle preheating, internal combustion engines, and auto generation were suggested. The results showed 82 % recovery of magnetic and non-magnetic metals, and production of synthetic fuels with PCI between 20 650 and 36 900 kJ/kg.

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Najib Khan, Abdul Shafiq Khan A., Nur Ezzah Faezah Othman, Hadi Purwanto, Hafasihah Abdul Halim, and Ahmad Firdaus Shamsul Baharin. "Synthetic of Pure Alumina from Aluminum Scrap." Advanced Materials Research 1115 (July 2015): 170–73. http://dx.doi.org/10.4028/www.scientific.net/amr.1115.170.

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Abundance in aluminum scrap metals can cause problem such as limited space allocation and pollution. The solution to solve these problems were by recycling the aluminum scrap metal as secondary production of aluminum. Among the recycling process alternative is smelting, However, the process consumes high energy with low productivity. This study focuses on alumina production from aluminum scrap waste. Dissolution process of Al scrap with 0.5M sodium hydroxide (NaOH) yields Al (OH)3and hydrogen gas. Results show that the temperature gradually decreased from 40°C to 35.7°C as the reaction took place. The pH of the solution during dissolution process increased from 12.08 to 12.38. The XRD results show that after calcination of Al (OH)3powders at 1500°C, α-Al2O3peaks could be observed. SEM morphology shows that the calcination process changes the Al (OH)3powders from hexagonal shape to form α-Al2O3with rounded shape.

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Wu, Zedong, Xiaochen Wang, Quan Yang, Dong Xu, and Jianwei Zhao. "Research on the Pre-Control of Side Scrap Blockage Failure during Trimming with the Side Trimmer." Metals 13, no. 10 (October 10, 2023): 1725. http://dx.doi.org/10.3390/met13101725.

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In the coupled pickling line and tandem cold mill (PL-TCM), the hot-rolled strip needs to be trimmed on both sides of the strip before the tandem cold rolling process to ensure stable operation of the rolling process. The equipment for trimming the strip is the side trimmer, and during trimming a failure of the side scrap blockage is often caused by the variation in the width of the hot-rolled strip and the deviation during the actual operation. For this problem, this paper established a finite element model of strip trimming by side trimmer, analyzed the influence of side scrap width, structure parameters, and strip specifications on the equivalent plastic strain at the trimmed position of the strip, and obtained the influence law of each factor during the trimming process. On this basis, by collecting the historical data of side scrap blockage failure of the side trimmer, the threshold value of the side scrap width setting is obtained. Combining the width data of the hot-rolled strip and the actual operation status monitoring of the strip in the inlet section of the PL-TCM, the side scrap blockage risk identification function and the speed reduction strategy of the side trimmer are designed to form the side scrap blockage pre-control model together. After applying the side scrap blockage pre-control model to a PL-TCM, a 40.5% reduction in side scrap blockage failures was achieved compared with the same length of time before the application, which achieved satisfactory results.

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Buahombura, Panya, Anuthai Kareram, Waraporn Piyawit, and Sarum Boonmee. "Hydrometallurgical Process for Selective Extraction of Nd and Rare-Earth Metals from End-of-Life Hard Disk Drives NdFeB Magnet Scrap." Key Engineering Materials 845 (May 2020): 81–86. http://dx.doi.org/10.4028/www.scientific.net/kem.845.81.

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This paper proposed a recycling process for neodymium-iron-boron (NdFeB) magnet scrap from the end-of-life (EOL) of hard disk drives by using hydrometallurgical process. Initial chemical composition of NdFeB magnet scrap was consisted of 25.37%Nd, 6.53%Pr, 0.90%Co, 3.63%B and 63.57%Fe. After de-magnetization and crushing into proper size, magnet scraps were directly leached by H2SO4 solution. More than 90% dissolved into acid solution with remaining small amount of residuals and Ni-coated metal. Neodymium precipitated from leached solution by pH-control to the optimum condition at pH 0.6 using NaOH solution. Solid Nd-precipitates XRD pattern was observed in form of NaNd (SO4)2.(H2O) and FeSO4.(H2O). Elemental analysis of Nd-precipitates by WD-XRF. The precipitates contained 26.50%Nd, 8.46%Pr and 1.19%Fe. In order to elimination of Fe, Nd-precipitates was leached by using H2SO4 solution to dissolve FeSO4.(H2O) into acid solution to obtain high concentration of Nd and rare-earth metals (REMs) compound. As a result, XRD pattern of Nd-compound after Fe-removal confirmed that the high purity NaNd (SO4)2.(H2O) compound was obtained. The final composition of precipitates analyzed by WD-XRF was 26.36%Nd, 8.13%Pr with Fe as low as 0.14%Fe.

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Fajkiel, A., P. Dudek, and T. Reguła. "Mechanical Properties of Magnesium Die Castings Produced Utilizing Process Scrap." Archives of Foundry Engineering 14, no. 4 (December 1, 2014): 31–34. http://dx.doi.org/10.2478/afe-2014-0081.

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Abstract Magnesium alloys are one of the lightest of all the structural materials. Because of their excellent physical and mechanical properties the alloys have been used more and more often in various branches of industry. They are cast mainly (over 90%) on cold and hot chamber die casting machines. One of the byproducts of casting processes is process scrap which amounts to about 40 to 60% of the total weight of a casting. The process scrap incorporates all the elements of gating systems and fault castings. Proper management of the process scrap is one of the necessities in term of economic and environmental aspects. Most foundries use the process scrap, which involves adding it to a melting furnace, in a haphazard way, without any control of its content in the melt. It can lead to many disadvantageous effects, e.g. the formation of a hard buildup at the bottom of the crucible, which in time makes casting impossible due to the loss of the alloy rheological properties. The research was undertaken to determine the effect of an addition of the process scrap on the mechanical properties of AZ91 and AM50 alloys. It has been ascertained that the addition of a specific amount of process scrap to the melt increases the mechanical properties of the elements cast from AZ91 and AM50 alloys. The increase in the mechanical properties is caused mainly by compounds which can work as nuclei of crystallization and are introduced into the scrap from lubricants and anti-adhesive agents. Furthermore carbon, which was detected in the process scrap by means of SEM examination, is a potent grain modifier in Mg alloys [1-3]. The optimal addition of the process scrap to the melt was determined based on the statistical analysis of the results of studies of the effect of different process scrap additions on the mean grain size and mechanical properties of the cast parts.

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Shmidt, D. V., Bashar Issa, and V. Yu Timofeev. "Preparation a Scrap of the Electronic Enterprises and its Subsequent Processing." Solid State Phenomena 303 (May 2020): 79–88. http://dx.doi.org/10.4028/www.scientific.net/ssp.303.79.

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The processing conditions of the of electronic wastes are largely dependent on environmental standards and requirements. Modern technologies for processing electronic waste should meet the increased demand for metals as well as the requirements. Electronic wastes can be classified as hazardous materials, as household and industrial electrical devices, which contain components such as batteries, capacitors, cathode ray tubes, etc. Electronic waste can consist of a large number of components of various sizes, shapes and chemical composition. Some of them contain hazardous metals, including mercury, lead, cadmium. The presence of precious metals in electronic waste such as gold, silver, platinum, palladium, as well as non-ferrous metals (copper, nickel, zinc, tin, etc.) make it attractive for processing. In industry, both hydrometallurgical and pyrometallurgical methods are used to extract valuable metals from electronic waste. Applied technologies may have both advantages and disadvantages.

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Konopka, Z., A. C. Chojnacki, M. Lagiewka, and A. Zyska. "The Influence of Home Scrap on Mechanical Properties of MgAl9Zn1 Alloy Castings." Archives of Foundry Engineering 17, no. 2 (June 27, 2017): 39–42. http://dx.doi.org/10.1515/afe-2017-0048.

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Abstract The work presents the results of examinations concerning the influence of various amounts of home scrap additions on the properties of castings made of MgAl9Zn1 alloy. The fraction of home scrap in the metal charge ranged from 0 to 100%. Castings were pressure cast by means of the hot-chamber pressure die casting machine under the industrial conditions in one of the domestic foundries. The examinations consisted in the determination of the following properties: tensile strength Rm, yield strength Rp0.2, and the unit elongation A5, all being measured during the static tensile test. Also, the hardness measurements were taken by the Brinell method. It was found that the mechanical properties (mainly the strength properties) are being improved up to the home scrap fraction of 50%. Their values were increased by about 30% over this range. Further rise in the home scrap content, however, brought a definite decrease in these properties. The unit elongation A5 exhibited continual decrease with an increase in the home scrap fraction in the metal charge. A large growth of hardness was noticed for the home scrap fraction increasing up to the value of 50%. Further increasing the home scrap percentage, however, did not result in a significant rise of the hardness value any more.

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Jensen, D. L., P. E. Holm, and T. H. Christensen. "Leachability of heavy metals from scrap dirt sampled at two scrap iron and metal recycling facilities." Waste Management & Research 18, no. 4 (August 2000): 367–79. http://dx.doi.org/10.1177/0734242x0001800409.

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Jensen, D. L., P. E. Holm, and T. H. Christensen. "Leachability of heavy metals from scrap dirt sampled at two scrap iron and metal recycling facilities." Waste Management and Research 18, no. 4 (August 2000): 367–79. http://dx.doi.org/10.1034/j.1399-3070.2000.00146.x.

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Arzpeyma, Niloofar, Moudud Alam, Rutger Gyllenram, and Pär G. Jönsson. "Model Development to Study Uncertainties in Electric Arc Furnace Plants to Improve Their Economic and Environmental Performance." Metals 11, no. 6 (May 29, 2021): 892. http://dx.doi.org/10.3390/met11060892.

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A statistical model is developed in order to simulate the melt composition in electric arc furnaces (EAFs) with respect to uncertainties in (1) scrap composition, (2) scrap weighing and (3) element distribution factors. The tramp element Cu and alloying element Cr are taken into account. The model enables simulations of a charge program as well as backwards estimations of the element concentrations and their variance in scrap. In the backwards calculation, the maximum likelihood method is solved by considering three cases corresponding to the involved uncertainties. It is shown that the model can estimate standard deviations for elements so that the real values lie within the estimated 95% confidence interval. Moreover, the results of the model application in each target product show that the estimated scrap composition results in a melt composition, which is in good agreement with the measured one. The model can be applied to increase our understanding of scrap chemical composition and lower the charged material cost and carbon footprint of the products.

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HAMADA, Atsushi. "Recycling of precious metals from scrap at Kushikino Mine." RESOURCES PROCESSING 47, no. 4 (2000): 177–81. http://dx.doi.org/10.4144/rpsj1986.47.177.

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Avarmaa, Katri, Marko Järvenpää, Lassi Klemettinen, Miikka Marjakoski, Pekka Taskinen, Daniel Lindberg, and Ari Jokilaakso. "Battery Scrap and Biochar Utilization for Improved Metal Recoveries in Nickel Slag Cleaning Conditions." Batteries 6, no. 4 (December 2, 2020): 58. http://dx.doi.org/10.3390/batteries6040058.

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Cobalt is a critical, high-value metal used extensively in batteries and other sustainable technologies. To secure its supply in future, it is utmost important to recover cobalt efficiently from industrial wastes and recycled End-of-Life batteries. This study aims at finding ways to improve the reduction of cobalt as well as valuable metals nickel and copper in nickel slag cleaning furnace conditions by using both traditional fossil-based coke and a more sustainable option, low-CO2 footprint biochar, as reductants. A cobalt-rich fraction of battery scrap (25.5 wt% Co) was also used as a secondary feed. The experimental technique consisted of reduction experiments with different times at 1400 °C under inert atmosphere, quick quenching and Electron Probe X-ray Microanalysis. The use of biochar resulted in faster reaction kinetics in the reduction process, compared to coke. Moreover, the presence of battery scrap had a clear impact on the behavior and reduction kinetics of the elements and/or enhanced settling and separation of matte and slag. The addition of scrap increased notably the distribution coefficients of the valuable metals but consequently also the iron concentration in matte which is the thermodynamic constraint of the slag cleaning process.

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Lezhnev, Sergey N., Abdrakhman B. Naizabekov, and Evgeniy Panin. "Radial-Shear Rolling as a New Technological Solution for Recycling Bar Scrap of Ferrous Metals." Materials Science Forum 1052 (February 3, 2022): 498–503. http://dx.doi.org/10.4028/p-dtc7hm.

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Recycling of waste, both ferrous and non-ferrous metals is a useful process for the economy of any country. In this paper, a new technology for recycling bar scrap of ferrous metals by rolling on radial-shear rolling mills was proposed to obtain a marketable product in the form of bars with an ultrafine-grained gradient structure. Studies have shown that the deformation of the rod of scrap pieces of rebar from steel 18G2S mill of radial-shear rolling can significantly dispersed structure with obtaining the gradient ultrafine-grained structure, and this in turn leads to an increase of the mechanical characteristics of this steel grade. Thus, the tensile strength of steel grade 18G2S deformed at the radial-shear rolling mill was 620 MPa (at the initial value of 365 MPa).

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Kwon, Namhun, Jong-Soo Byeon, Hyun Chul Kim, Sung Gue Heo, Soong Ju Oh, Sang-hoon Choi, Seok-Jun Seo, and Kyoung-Tae Park. "Effective Deoxidation Process of Titanium Scrap Using MgCl2 Molten Salt Electrolytic." Metals 11, no. 12 (December 8, 2021): 1981. http://dx.doi.org/10.3390/met11121981.

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To overcome the scarcity and resource limitations of Ti metal, deoxidation of Ti scrap was conducted through electrolytic refining and chemical reaction with MgCl2 molten salt electrolysis. The oxygen concentration in Ti scraps was decreased by the electrochemical and chemical reactions generated by the applied voltages. The optimized conditions for the process were derived by controlling the conditions and parameters by decreasing the thermodynamic activity of the reactants. The correlation between the deoxidation efficiency and the behavior of the voltage and current was confirmed by setting the conditions of the electrolysis process in various voltage ranges. In addition, the correlation between the presence of impurities and the measured oxygen concentration was evaluated. The surface element analysis result indicated that the salt that was not removed contained a certain amount of oxygen. Thus, the removal efficiencies of impurities and particles by deriving various post-treatment process conditions were analyzed. The results confirmed that the most stable and efficient current was formed at a specific higher voltage. Moreover, the best deoxidation result was 2425 ppm, which was 50% lower than that of the initial Ti scrap.

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Lezhnev, S. N., A. B. Naizabekov, I. E. Volokitina, E. A. Panin, and E. I. Kuldeyev. "Radial-shear rolling as a new technological solution for recycling bar scrap of ferrous metals." Kompleksnoe Ispolʹzovanie Mineralʹnogo syrʹâ/Complex Use of Mineral Resources/Mineraldik Shikisattardy Keshendi Paidalanu 316, no. 1 (March 15, 2021): 46–52. http://dx.doi.org/10.31643/2021/6445.06.

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Waste recycling of both ferrous and non-ferrous metals is a useful process for the economy of any country. This paper proposes a new technology for recycling bar scrap of ferrous metals by rolling it in radial-shear rolling mills by producing a commercial product in the form of bars with an ultrafine-grained gradient structure. Studies have shown that the deformation of bar scrap in the form of pieces of reinforcement made of steel grade 18G2S in a radial-shear rolling mill makes it possible to significantly disperse its structure by producing a gradient ultrafine-grained structure, and this, in turn, leads to the elevating of the mechanical characteristics of this steel grade. Thus, the tensile limit of the 18G2S grade steel deformed on the radial-shear rolling mill was 620 MPa (at the initial value of 365 MPa).

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Suponik, Tomasz, and Marcin Lutyński. "IN-SITU TREATMENT OF GROUNDWATER CONTAMINATED WITH UNDERGROUND COAL GASIFICATION PRODUCTS / OCZYSZCZANIE IN-SITU WÓD PODZIEMNYCH ZANIECZYSZCZONYCH PRZEZ PRODUKTY PODZIEMNEGO ZGAZOWANIA WĘGLA." Archives of Mining Sciences 58, no. 4 (December 1, 2013): 1263–78. http://dx.doi.org/10.2478/amsc-2013-0087.

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Abstract In the paper the contaminants that may be generated in Underground Coal Gasification (UCG) process were listed and include mainly mono- and polycyclic aromatic hydrocarbons, phenols, heavy metals, cyanides, ammonium, chloride and sulphate. As a method of UCG contaminated groundwater treatment a Permeable Reactive Barrier technology was proposed. To assess the effectiveness of this technology two tests were carried out. Granulated activated carbon (GAC) and zeolite, and granulated activated carbon and scrap iron were applied in the first and second test respectively. For these materials the hydro geological parameters called reactive material parameters were determined and discussed. The results of the experiments showed that GAC seems to be the most effective material for phenols, BTX, PAH, cyanides and slightly lowers ammonia removal, while zeolites and scrap iron removed free cyanide, ammonia and heavy metals respectively.

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Toivanen, Kati. "One man's waste is another man's business." Tekniikan Waiheita 42, no. 1 (June 14, 2024): 6–36. http://dx.doi.org/10.33355/tw.136159.

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A form of “green entrepreneurship” was born and developed in Finland during the first decades of the 20th century but not intentionally and not on ecological principles. As the melting technology in iron and steel industry developed considerably in the earlier decades, it slowly created demand for and supply of more raw material. Gradually, scrap became the most important and valuable waste raw material. A huge leap in technology, changes in national legislation concerning freedom of occupation, and the growing waste problem created a new group of professionals. Many new entrepreneurs came from marginalized ethnic, social, or religious groups with few options. This paper examines the birth of Finnish scrap business as a systematic profession to collect and sort scrap iron and metals and to deliver them to the iron and steel industry and engineering works, from around 1900 until 1930. The focus is on two themes: the demand for, and the size of the new profession, and the status and background of the entrepreneurs. Who were they? How did they succeed? How did scrap materials circulate?

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Journal articles on the topic 'Scrap metals'

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