Scrap Processing Research Articles

Development and optimization of the parameters of processing (firing) of cable scrap with PVC insulation by steam gasification

Development and optimization of the parameters of processing (firing) of cable scrap with PVC insulation by steam gasification

Live fitting of process data within digital twins of manufacturing to use simulation and optimisation

ABSTRACT In production scenarios, uncertainty in production times, and scrap rates is common. Uncertainty can be described by stochastic models that need continuous updates due to changing conditions. This paper models probability distributions and estimates their parameters from real-world data on processing times and scrap rates. It uses live fitting to identify timely changes in the data sets, comparing different distributions. The fitting and live fitting approaches are applied to data from a real production system to compare the goodness of fit for different distributions and to demonstrate the reliability of the reaction to changes in the input data. Data and probability estimations are categorised, and a concept combining simulation and optimisation models is developed to optimise scheduling. The vision of the research presented in this paper is an online approach that determines quasi-optimal schedules for production systems based on current data from the system and its environment.

Microstructural Investigation of Discarded NdFeB Magnets After Low-Temperature Hydrogenation

Due to continuously increasing demand and limited resources of rare-earth elements (REEs), new solutions are being sought to overcome the supply risk of REEs. To mitigate the supply risk of REEs, much attention has recently been paid to recycling. Despite the more common recycling methods, including hydrometallurgical and pyrometallurgical processes, hydrogen processing of magnetic scrap (HPMS) is still in the development stage. Magnet-to-magnet recycling via hydrogenation of discarded NdFeB magnets provides a fine powder suitable for the production of new magnets from secondary sources. One of the crucial aspects of HPMS is the degree of recovery of the magnetic properties, as the yield efficiency can easily reach over 95%. The amount, morphology, and distribution of the Nd-rich phase are the key parameters to achieve the excellent performance of the magnet by isolating the matrix grain. Therefore, a better insight into the microstructure of the matrix grains and the Nd-rich phase before and after hydrogenation is essential. In this study, a low-temperature hydrogenation process in the range of room temperature to 400 °C was conducted as the first step to recycle NdFeB magnets from discarded hard disk drives (HDDs), and the hydrogenated powder was characterized by electron microscopy and X-ray diffraction. The results show that there are three different morphologies of the Nd-rich phase, which undergo two different transformations through oxidation and hydride formation. While at lower temperatures (below 250 °C) the degree of pulverization is higher and the experimental evidence of hydride formation is less clear, at higher temperatures the degree of pulverization decreases. The formation of neodymium hydride at higher temperatures prevents further oxidation of the Nd-rich phase due to its high stability.Graphical

Co-production of sugars and aroma compounds from tobacco waste using biomass-degrading enzymes produced by Aspergillus brunneoviolaceus Ab-10.

Biomass-degrading enzymes produced by microorganisms have a great potential in the processing of agricultural wastes. In order to produce suitable biomass-degrading enzymes for releasing sugars and aroma compounds from tobacco scraps, the feasibility of directly using the scraps as a carbon source for enzyme production was investigated in this study. By comparative studies of ten fungal strains isolated from tobacco leaves, Aspergillus brunneoviolaceus Ab-10 was found to produce an efficient enzyme mixture for the saccharification of tobacco scraps. Proteomic analysis identified a set of plant biomass-degrading enzymes in the enzyme mixture, including amylases, hemicellulases, cellulases and pectinases. At a substrate concentration of 100g/L and enzyme dosage of 4mg/g, glucose of 17.6g/L was produced from tobacco scraps using the crude enzyme produced by A. brunneoviolaceus Ab-10. In addition, the contents of 23 volatile molecules, including the aroma compounds 4-ketoisophorone and benzyl alcohol, were significantly increased after the enzymatic treatment. The results provide a strategy for valorization of tobacco waste by integrating the production of biomass-degrading enzymes into the tobacco scrap processing system.

Hydrometallurgical Method of Producing Lithium Perrhenate from Solutions Obtained during the Processing of Li-Ion Battery Scrap

The work presents the research results regarding the development of an innovative technology for the production of lithium perrhenate. The new technology is based entirely on hydrometallurgical processes. The source of lithium was solutions created during the processing of Li-ion battery masses, and the source of rhenium was perrhenic acid, produced from the scraps of Ni-based superalloys. The research showed that with the use of lithium carbonate, obtained from post-leaching solutions of Li-ion battery waste and properly purified (by washing with water, alcohol, and cyclic purification with CO2), and perrhenic acid, lithium perrhenate can be obtained. The following conditions: room temperature, time 1 h, 30% excess of lithium carbonate, and rhenium concentration in the acid from 20 g/dm3 to 300 g/dm3, allowed to produce a compound containing a total of 1000 ppm of metal impurities. The developed technology is characterized by the management of all aqueous waste solutions and solid waste and the lack of loss of valuable metals such as rhenium and lithium after the initial precipitation step of lithium carbonate.

Analize Die Casting process and Structure of HDF 12 Material for Lower Arm

Steel is part of raw material for manufacturing process making a product. Ferro Casting Ductile is part of manufacturing process from iron ore to be metal part using casting process. Die casting is a part of manufacturing process especially in automotive industries for engine of vehicle production process. this research will be focus on casting process, Ferro Casting Ductile (FCD). In this research using material steel HDF 12 Material, in this process production Magnesium, Pig Iron, Scrap, Silicon, Carburizer, Inoculant and Slagtol. Manufacturing process is melting process of all raw material using temperature (melting point) at 1100 - 1400 ºC. When Specimen finish to process production will be analyze using spicrometer and SM machine for check of characteristic material and structure for crack issue. The result show that after casting process, the HDF12 have composition rate iron (Fe) content, namely 93.37% and also carbon (C) 3.82% and silicon (Si) 2.31% after check using. As visual check after die casting, lower arm is there no any crack, flash, flow mark finding by visual check inspection result. SEM Measurement check result until 300μm the result show that no any finding crack issue and result of Tensile strength of material Lower Arm upper limit is 433Kgf/cm2 and lower limit is 420 Kgf/cm and Elongation is 32%.

WaveSegNet: An Efficient Method for Scrap Steel Segmentation Utilizing Wavelet Transform and Multiscale Focusing

Scrap steel represents a sustainable and recyclable resource, instrumental in diminishing carbon footprints and facilitating the eco-friendly evolution of the steel sector. However, current scrap steel recycling faces a series of challenges, such as high labor intensity and occupational risks for inspectors, complex and diverse sources of scrap steel, varying types of materials, and difficulties in quantifying and standardizing manual visual inspection and rating. Specifically, we propose WaveSegNet, which is based on wavelet transform and a multiscale focusing structure for scrap steel segmentation. Firstly, we utilize wavelet transform to process images and extract features at different frequencies to capture details and structural information in the images. Secondly, we introduce a mechanism of multiscale focusing to further enhance the accuracy of segmentation by extracting and perceiving features at different scales. Through experiments conducted on the public Cityscapes dataset and scrap steel datasets, we have found that WaveSegNet consistently demonstrates superior performance, achieving the highest scores on the mIoU metric. Particularly notable is its performance on the real-world scrap steel dataset, where it outperforms other segmentation algorithms with an average increase of 3.98% in mIoU(SS), reaching 69.8%, and a significant boost of nearly 5.98% in mIoU(MS), achieving 74.8%. These results underscore WaveSegNet’s exceptional capabilities in processing scrap steel images. Additionally, on the publicly available Cityscapes dataset, WaveSegNet shows notable performance enhancements compared with the next best model, Segformer. Moreover, with its modest parameters and computational demands (34.1 M and 322 GFLOPs), WaveSegNet proves to be an ideal choice for resource-constrained environments, demonstrating high computational efficiency and broad applicability. These experimental results attest to the immense potential of WaveSegNet in intelligent scrap steel rating and provide a new solution for the scrap steel recycling industry. These experimental results attest to the immense potential of WaveSegNet in intelligent scrap steel rating and provide a new solution for the scrap steel recycling industry.

Production of Permanent Magnets from Recycled NdFeB Powder with Powder Extrusion Moulding

In the last fifteen years, several groups have investigated metal injection moulding (MIM) of NdFeB powder to produce isotropic or anisotropic rare earth magnets of greater geometric complexity than that achieved by the conventional pressing and sintering approach. However, due to the powder’s high affinity for oxygen and carbon uptake, sufficient remanence and coercivity remains difficult. This article presents a novel approach to producing NdFeB magnets from recycled material using Powder Extrusion Moulding (PEM) in a continuous process. The process route uses powder obtained from recycling rare earth magnets through Hydrogen Processing of Magnetic Scrap (HPMS). This article presents the results of tailored powder processing, the production of mouldable feedstock based on a special binder system, and moulding with PEM to produce green and sintered parts. The magnetic properties and microstructures of debinded and sintered samples are presented and discussed, focusing on the influence of filling ratio and challenging processing conditions on interstitial content as well as density and magnetic properties.

Evaluating the Efficiency of Using Coherent-Type Nozzles for the Conditions of Additional Postcombustion of CO to CO2 in the Wor king Space of the Oxygen Converter

Introduction. The requirements for the working conditions of metallurgical industry have been becoming stricter, both in terms of increasing the process indicators and in terms of environmental friendliness of processes.Problem Statement. The main controlling factor of the oxygen-converter process is the oxygen jet supplied through the nozzles of the top lance. The main task of the process is the active mixing for refi ning and the provision of conditions for the postcombustion of CO to СО2 in off -gases to additionally increase the heat content of the bath in order to enable increasing scrap processing, which improves the environmental friendliness of the process. In electrometallurgy, to solve the problem of deep mixing, it has been proposed to use nozzles of the coherent type (like a cylinder in a cylinder, through which oxidizing and protective gases are supplied).Purpose. To study and to establish the features of using nozzles of the coherent type for the conditions of top oxygen purging in the converter.Materials and Methods. Samples of laboratory nozzles of the coherent type, which diff er in the ratio of the central and peripheral parts (75, 50, 25%) with respect to the force of the jet, have been studied with the use of a modifi ed liquid manometer; by two-phase cold modeling; by evaluating the degree of afterburning of CO-containing gases in comparison with the performance parameters of an equivalent cylindrical nozzle.Results. It has been established that the force with which the jet fl owing out of the nozzle acts on the liquid is signifi cantly less when that in the case of coherent type nozzles and decreases as the share of the peripheral part of the nozzle increases. According to the results of two-phase cold modeling, it has been noted that the use of coherent type nozzles contributes to the active formation of a foamed emulsion and increases the activity of mixing two-phase liquids during top blowing. The use of the coherent-type nozzles with a peripheral part of 75% increases the postcombustion of CO-containing gases by 42.36%.Conclusions. According to the obtained results, it is possible to recommend the use of nozzles of the coherent type to replace the cylindrical nozzles of oxygen lances, which perform the function of additional sources of infl uence on the bath and for the oxidation of CO in the waste gases.

ENVIRONMENTAL ASPECTS OF PROCESSING GRANULAR FILTERS FOR PRIMARY ALUMINUM REFINING

This article presents the results of experimental studies on the involvement in the processing of used filters from ash and slag waste used in the refining of primary aluminum as a filler in the production of concrete for building products. The research was carried out within the framework of grant funding from the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan under the competition «Zhas Galym» under the project IRN AR19175493 «Development of technology for refining primary aluminum with filters with an active surface». The recycling of used grain filters was carried out in three stages: preliminary processing of filter grains to remove aluminum scrap; metallurgical processing of separated aluminum scrap by remelting in an induction crucible furnace and refining using complex technology described by the authors in the work; obtaining a concrete mixture based on crushed waste filter grains, quartz sand and bauxite sludge, screenings from crushing rocks with a fraction of 20–30 mm and Portland cement to obtain samples of construction products. According to the test results, the tensile strength of concrete samples of building products is 20.89–37.75 MPa, depending on the content of Portland cement (from 20 to 40 %) and corresponds to the class of heavy concrete. Keywords: aluminum, granular filter, ash, waste, recycling.

Accu Scrap Raw Material Inventorycontrol Using the Min- Max Method

This research investigates the efficacy of implementing the Min-Max method to enhance inventory control performance in a manufacturing setting converting ACCU scrap into tin metal. Focused on two product types, bullion, and ingots, the study aims to optimize inventory policies by determining safety stock, minimum and maximum stock levels, order quantities, and reorder points to mitigate stockouts and overstocks. Results demonstrate a significant improvement, with the Min-Max method enabling a 33% increase in raw material control effectiveness compared to previous methods. This research underscores the potential for the Min-Max approach to provide practical solutions for inventory management challenges in manufacturing, offering valuable insights for industry practitioners and researchers alike. Highlight : The Min-Max method improved inventory management effectiveness by 33%. This approach facilitated the determination of safe stock levels, minimal order quantities, and reorder points. Manufacturers experienced reduced operating expenses while maintaining competitive edge and responsiveness to market dynamics. Keywords: Accu scrap processing, Min-Max method, inventory control, supply chain optimization, resource allocation

A bottom-up assessment of recent (2016–20) energy use by the global iron and steel industry constrained to match a top-down (International Energy Agency) assessment

This paper presents the first estimates, at the global scale, of energy use by energy type associated with individual steps in the production of fabricated steel products. Estimates are averaged over the period 2016–20, based on a synthesis of literature regarding energy use for (i) preparation of iron ore; (ii) production of iron in a blast furnace (BF) and as direct reduced iron; (iii) production of refined steel in the basic oxygen furnace or electric arc furnace; (iv) steel casting, hot and cold rolling, and coating; (v) fabrication of intermediate steel products; and (vi) processing of scrap. The International Energy Agency provides separate global energy use for coking, transformation energy use by BF, and by the remainder of the iron and steel industry (rISI) including the remaining BF energy use. With re-allocation of the BF portion of rISI back to BF, and a 9% increase in literature-based estimates of energy intensity across all production steps except coking, bottom-up and IEA estimates of total energy use agree. The resulting mean cumulative energy intensity of fabricated steel products is 24.1 GJ/t. The energy content of the lost iron equals about 10% of the total energy used in producing finished steel products.

Effect of Surface Condition on the Results of Chemical Composition Measurements of Scrap Copper Alloys

The processing of copper-bearing scrap makes it possible to reduce the costs and energy consumption of obtaining copper alloy products compared to producing them from primary raw materials. To achieve this, it is necessary to quickly and accurately determine the content of alloying elements in individual scrap elements. However, the copper-bearing scrap obtained at secondary raw materials collection points consists of elements with various surface conditions (due to contamination, shape, paint coatings, roughness, etc.). The paper contains research results on the influence of surface roughness and paint coatings on the measurement result of the content of alloying elements in copper-bearing scrap. Three mobile spectrometers were used for measurements: spark-induced optical emission spectroscopy (OES), X-ray fluorescence spectrometry (XRF) and laser-induced breakdown spectroscopy (LIBS). The tests used elements with different surface roughness (from Ra = 0.03 μm to 6.7 μm) and covered with various types of varnish (alkyd, water-based, oil-phthalic, acrylic, oil-alkyd). It was found that the roughness of Ra < 2 μm does not significantly affect the results of the measurements with the OES and LIBS spectrometers, and a larger scatter of measurement results was observed for the XRF spectrometer compared to OES and LIBS. For Ra > 2 μm, a significant impact of roughness was found on the measurement results (this may result in the erroneous classification of the scrap as an incorrect material group). The influence of paint coatings on the measurement is much stronger compared to surface roughness. Even a single layer of paint can cause a change in the measurement result of the content of alloying elements by more than 10%. In the case of an OES spectrometer, paint coatings may prevent the measurement from being performed (which means that no measurement result can be acquired).

Study on the behavior of clusters in the physical recovery of GaAs scrap

Gallium arsenide (GaAs) is the most widely used second-generation semiconductor material. However, a large amount of GaAs scrap is generated at various stages of the GaAs wafer production process. Volatile GaAs clusters are inevitably generated during the process of GaAs vacuum thermal decomposition, resulting in lower purity of the recovered arsenic and the loss of gallium. In this study, thermodynamic analysis and dynamics simulation were combined to discuss the possibility of separating GaAs clusters and arsenic from a microscopic perspective. A vacuum thermal decomposition-directional condensation recovery process for GaAs scrap was proposed. By properly adjusting the separation parameters such as heating temperature, holding time and raw material size, high purity of gallium (99.99%) and arsenic (99.5%) were directly recovered under a system pressure of 1 Pa, heating temperature of 1323 K, holding time of 3 h, and GaAs scrap size of 2.5 cm. GaAs clusters were also recovered in powder form. The problem of difficult separation of GaAs clusters from arsenic was effectively solved by this method, and the purity of recovered arsenic was greatly improved. No additives are required and no waste liquid or gas emission in the whole process. The complexity of subsequent arsenic purification operations and the threat of arsenic containing waste to the environment were reduced as well.

Processing of Electronic Scrap with Ausmelt TSL Technology

Continued decreasing of the world’s average copper ore grades, coupled with a meteoric rise in the generation of consumer waste streams, has led to the processing of electronic scrap (e-scrap) and other secondaries assuming increasing importance within the global copper industry. Treatment of these secondary feeds has traditionally been carried out in the Blast furnace, Peirce-Smith converter and/or anode furnace. More recently however, bath smelting processes such as the Ausmelt TSL and Outotec Kaldo technologies have emerged as the preferred option for processing these materials due to their superior environmental performance and flexibility to operate under a wide range of conditions. Furthermore, the ability of these processes to handle a wide range of feed inputs make them ideally placed for the processing of not only e-scrap but also other waste streams from the clean energy transition such as end of life e-mobility batteries and photovoltaic systems. This paper focuses on the processing of electronic scrap and other copper secondaries with Ausmelt TSL technology and discusses specific issues facing secondary copper smelters in relation to impurity management and process offgas handling/cleaning.

Global market trends for secondary processing of copper waste and scrap (analytical review)

Global market trends for secondary processing of copper waste and scrap (analytical review)

Work Environment Analysis Using 5S (SEIRI, SEITON, SEISO, SEIKETSU, SHITSUKE) Assessment Method

The working environment in a company specializing in Aluminum Scrap Processing, currently lacks organization and cleanliness. This hampers operational efficiency and poses safety risks. To address this issue, the 5S assessment method is employed across the charging, casting, and shipping stations. The 5S steps – Sort, Set in order, Shine, Standardize, and Sustain – are implemented to enhance cleanliness, organization, and efficiency. Through direct observation, it is anticipated that the application of the 5S method will lead to a more orderly, clean, and safe work environment. This, in turn, is expected to improve operational quality and product output.

An Innovative Method of Leaching of Battery Masses Produced in the Processing of Li-Ion Battery Scrap

This paper presents comparative experimental results for the single-stage and two-stage counter-current acid leaching of battery masses, with the addition of a booster, from different types of LIB waste. Three different types of battery masses were used in this research: Material I, module car; Material II, tablets and laptops; and Material III, mobile phones. These materials were obtained during the mechanical processing of Li-ion battery waste, which were dried at a temperature in the range of 80–180 °C. Leaching studies of these materials were carried out using the single-stage acid leaching method with the addition of hydrogen peroxide, and the innovative two-stage counter-current acid leaching method, also with the addition of hydrogen peroxide. The single-stage leaching of the battery mass (regardless of the composition of the material) in a 15% or 20% sulfuric acid solution with the addition of 30% H2O2 aqueous solution, for 2 h, with a solid-to-liquid-phase ratio of 1:5 or 1:4 at a temperature of 60 °C ensures the leaching of cobalt, nickel, copper and lithium with efficiencies above 95%. On the other hand, the use of an innovative method of two-stage counter-current leaching of the battery mass ensures the leaching of cobalt, nickel, copper and lithium at a level significantly greater than 95%, while obtaining a concentration of cobalt in the leaching solution at a level of nearly 50 g/dm3. It also reduces the leaching time of a single stage to 1 h and, importantly, reduces the amount of waste solutions and the consumption of H2O2 and sulfuric acid. The developed method of the two-stage counter-current leaching of battery masses is therefore characterized by high efficiency and low environmental impact, thanks to which it can be used in commercial processes for the recycling of lithium-ion batteries.

ДРІБНОЗЕРНИСТІ ЗАПОВНЮВАЧІ АСФАЛЬТОБЕТОННИХ СУМІШЕЙ З ПРОДУКТІВ РЕСАЙКЛІНГУ БУДІВЕЛЬНОГО ЛОМУ

The substantiation of the need to develop and implement new resource-saving technologies for the production of construction mixtures using aggregates obtained as a result of complex processing of solid inorganic construction waste is provided. Analytical studies of technogenic waste processing technologies for obtaining building materials have been conducted. The results of the study of the experience of construction scrap processing are presented, with confirmation of the expediency of the fact that the technology of recycling accumulated construction scrap dumps in the territory where the destroyed buildings were located does not require any new specialized measures. The projected volumes of building materials in the composition of residential construction objects with various quantitative parameters of the constituent components of the elements of the fencing structures are presented. Analytical studies have established that the accumulated volumes of construction scrap from the destruction of elements of buildings and structures in the vast majority include the remains of concrete, reinforced concrete, expanded clay concrete, brickwork made of ceramic and silicate products. Experimental series of aggregate samples were made using experimental samples of construction scrap, their granulometric characteristics were determined and physical parameters were investigated. With the use of regulatory and technical literature, the predicted prescription parameters of the concrete mixture using a new variety of aggregates obtained by re-processing of construction scrap were compiled. The presence of reactive substances on the surface of the obtained aggregates was substantiated and the presence of increased physical and mechanical characteristics of the samples with a decrease in the binder content was confirmed. Recipe and technological parameters for the production of wall building materials using the obtained multicomponent building mixtures are proposed. The results of tests of physical and mechanical characteristics of test samples of concrete using aggregates from solid inorganic waste are presented.

Reduction of energy and fuel consumption in the hot-rolling steel sector

Furnace oil consumption, electric energy consumption, waste owing to mill scale, and process scrap due to cropping length are essential production indicators that must be monitored for economical production with minimal environmental impact.The study examined the effect of mill setting schedules or roll pass designs on furnace oil consumption, electricity consumption, mill scale generation and end cropping loss in a steel bar hot rolling plant. Rolling experiments were performed in a hot rolling steel plant. The results obtained from the rolling plant experiments were compared with the results obtained with the help of computer simulation.A t-test is an inferential statistic used to determine if there is a significant difference between the means of two groups. The results of plant experimentation and simulation were compared by performing t-test. The simulations results were found to be comparable to experimental results. After validation, simulation experiments were performed for the mill setting process parameters beyond the range possible in the rolling plant. Regression equations linking input process parameters with response parameters were created with the help of statistical analysis.The optimum mill setting parameters for minimum consumption of fuel oil, electrical energy, minimum generation of mill scale and end cropping loss have been attained.