Cupola Furnace Research Articles

Physico-chemical characterization of cupola slag: Enhancing its utility in construction

Cupola slag is a waste material of the steel and iron industries. Its composition is determined by the cupola furnace and other elements used in steel and iron manufacturing. This paper investigates the characterization behavior of various cupola slag materials. As a result, x-ray fluorescence (XRF), x-ray diffraction (XRD), thermogravimetry differential thermal analysis, and scanning electron microscopy (SEM) methods were used to characterize three cupola slag samples from distinct origins. In addition, various physical properties were used to compare different cupola slags. The specific gravity values of CS-1 (cupola slag-1 sample), CS-2 (cupola slag-2 sample), and CS-3 (cupola slag-3 sample) are 1.36, 2.5, and 2.917, respectively. The density and water absorption for CS-1, CS-2, and CS-3 are 1414.86, 1477.71, and 1796 kg/m3, and 0.37%, 0.32%, and 0.26%, respectively. Cupola slag also includes a larger percentage of lime, according to XRF data, which contributes to its improved binding characteristics. A higher calcium oxide content in CS-3 could facilitate the pozzolanic process. The presence of angular particles that aid in material binding is seen in the SEM image. Compounds with a nanostructure are then flawlessly blended into the mixture and grouped with calcium alumina silicates formed by cement hydration. The XRD pattern of cupola slag exhibits high peaks, indicating that the material is crystalline in character and can be utilized as sand. It also shows the presence of other chemical compounds, such as silica, which ranges from 30% to 45%. CS-1 and CS-2 have comparable XRD patterns. However, CS-3 has a somewhat different pattern because of the greater CaO content. Weight loss begins at higher temperatures, which shows that the material is stable at higher temperatures, according to a thermo-gravimetric study. The differential thermal analysis curve of CS-3 indicates that the material remains stable up to a temperature of 600 °C. The physical characteristics of all cupola slag samples show that cupola slag may be utilized to make sustainable building materials because of its lower specific gravity, density, and water absorption.

Influence of concentration of causid sodium solution on the structure formation of cement matrix from flow dust from mineral wool production

One of the ways to utilize mineral wool production waste is to use it in an alkaline hydraulic binder. However, this requires an assessment of the structure of the raw material and the effect of the alkaline activator on it. The article presents the results of a study of the influence of caustic soda solution concentrations of 5,6,7,8,9,10 mol/l on the properties of a cement-sand solution from dust-flying gas purification system of a cupola furnace of mineral wool production. The features of the formation of a cement matrix with changes in concentration have been studied. The maximum compressive strength of 28 MPa and flexural strength of 7.1 MPa were obtained at a concentration of 6 mol/l. It has been established that when dust is mixed with water, the mineral calcium silicate hydrate – gismondine – is formed. During the geopolymerization reaction, gismondin is significantly reduced due to the formation of N-A-S-H gel and ziolites.

Study of durability and mechanical properties for utilization of cupola slag as a coarse aggregate in M20 grade green concrete

Cupola slag is an industrial waste generated from cupola furnaces during cast iron production. The disposal of cupola slag is a matter of burden for the manufacturers of casting industry. This experimental study aims to reuse cupola furnace slag (CFS) in the construction industry, developing a novel way of solid waste management. In the M20 grade concrete, CFS is used as coarse aggregate (CA), partially replaced by 0–50 wt % in the step of 10 wt %. The mechanical and durability properties of the CFS-based concrete were examined after the required days of curing. The experimental result exposed that the dry density decreases with the increased weight percent of CFS in concrete. The cast samples with up to 40 wt% partial replacement of CFS effectively meet the requirements for the M20 grade of concrete in terms of compressive strength. A similar trend for the split tensile strength was observed, like the compressive strength. Durability test results reveal that water penetration depth increases with increased CFS weight percent in concrete. Moreover, in the case of rapid chloride penetration test, chloride ions penetration is decreased with the increase of CFS weight percent in concrete. FESEM, EDS and XRD were used to examine the microstructure, elemental mapping and phase analysis of the CFS-based concrete. According to the investigation, CFS is a sustainable material that works well as a partial replacement for natural CA in concrete.

Diagnostic Methodology for the Energy Efficiency Estimation in Small Metal Casting Industries.

This study will develop a methodology to measure and find the energy efficiency in arc furnaces, crucible furnaces and cupola furnaces. Those are the only ones used in the small metal casting industries in Cali. The methodology initiates with the elaboration of a survey and contacting a sample OF local companies, then, continues with technical visits, measurements, analysis and results and finally, we obtain conclusions and give some specific recommendations to the companies As a result, the first documented characterization were done, where is shown: size of the industry, energetic resource used, level of technification (modernization), fused metal, smelting method and kind of furnace, it is also presented the validation methodology and the identification of critical points where they can obtain big energy savings.

Effects of repetitive production on the mechanical characteristic and chemical structure of green tea bio-coke

A new type of solid biofuel called bio-coke has been developed, which has the potential to replace the use of coal coke in cupola furnaces. This study aimed to improve the mechanical properties of green tea (GT) bio-coke by implementing repetitive production. The properties of unprocessed GT, the initial production of GT bio-coke (known as GT BIC-1), and its subsequent iterations; the 2nd time GT bio-coke (GT BIC-2) and 3rd time GT bio-coke (GT BIC-3) were examined. It was found that repetitive bio-coke improved their mechanical capabilities. The mechanical strength at 700 °C known as an essential quality to indicate the permeability of bio-coke in the cupola furnace. In comparison to GT BIC-1 (9.20 ± 1.38 MPa), GT BIC-2 and GT BIC-3 demonstrated higher mechanical strength at 700 °C with values of 14.37 ± 1.98 and 16.18 ± 0.50 MPa, respectively. This study also investigates the relationship between the structural transformation and the mechanical characteristics of the bio-cokes. The enhanced aromatic (ARM) and hydrophobicity (HB) index in GT BIC-2 and GT BIC-3 have influenced their rigidity, high temperature tolerance, and water resistance. This suggests that coal coke substitution using repetitive bio-coke in cupola furnaces could be a viable approach to reduce greenhouse gas (GHG) emissions in the future.

A reuse approach of grinding sludge: Analysis of corrosion and mechanical properties of oxyacetyline torch melted Fe and Cu alloy

This study mainly focuses on investigating the feasibility of utilizing grinding sludge, a by-product of grinding steel plates, as an alternative raw material by filtering and compressing the sludge, removing impurities, adding copper wire bits, and analyzing the resulting samples for improved hardness and corrosion resistance. To improve the hardness and convert the sample to a definite shape, copper wire bits are added to the separated Fe particles during melting. These copper wire bits, which are common scrap available during electrical maintenance, are melted together with Fe particles using the oxy-fuel steel cutting torch at a temperature range of 1539–1600 °C. The melted samples are then characterized using XRD, optical, and scanning electron microscopy analyses. The XRD results confirm the presence of a body-centered cubic lattice structure. Optical and scanning electron microscopy analyses reveal the formation of grains and the mixing of Cu with Fe. Further investigations are conducted to analyze the strength and corrosion properties of the samples. Micro-hardness and electrochemical analysis are performed, and the results show that the addition of copper wire bits improves the corrosion resistance and micro-hardness of the Fe. The fact that the addition of copper wire bits during the melting process improved the corrosion resistance and micro-hardness of the Fe means that the samples can now be sent to the cupola furnace for melting and reuse. This is a sustainable approach that will allow for the responsible disposal of the materials, while also potentially reducing the need for new materials in future production processes.

РЕСУРСОЗБЕРІГАЮЧИЙ БЕЗПЕРЕРВНИЙ ОПТИЧНИЙ КОНТРОЛЬ ТЕМПЕРАТУРИ РІДКОГО МЕТАЛУ В МЕТАЛУРГІЇ ЕНЕРГЕТИЧНОГО МАШИНОБУДУВАННЯ

The article is devoted to the problem of the most effective and non-alternative continuous optical temperature control of metallurgical aggregates in machine building metallurgy. The aim of the article is to develop and investigate the technologies of continuous temperature control on the base of classical and spectral (multicolor) thermometry. To achieve thе aim, the next methods have been used: analysis of literature sources; experimental investigations of influence regularities of sighting zones, time of tapping, intensity of mixing and liquid metal temperature on one color radiation temperature of liquid metal in visible and infrared spectrum ranges under industrial conditions; statistical processing of the results of direct and indirect measurements with their errors estimation. It has been found the main role of thermometry in the metrological support structure of metallurgical plants. The production volumes of world machine building metallurgy have been analyzed, particularly, the part of metallurgy of energy machine building in it. Metallurgical equipment to be used for liquid metal obtaining and treatment has been classified from thermometric position. The stability of radiation characteristics of liquid metal in cupola, arc and induction furnaces has been investigated under conditions of different impact factors. The methodical errors of optical temperature measurements of liquid metal during tapping from cupola and arc furnaces on the base of classical energy thermometry have been estimated. In special determined сases these errors don’t exceed 1,0–1,5% with confidence level 0,997. Under another conditions these errors reaches 8% and this fact stimulates transition to the spectral thermometry. With the use of modern elemental base, the technologies of spectral measurements of temperature and emissivity have been developed. The technologies include: symmetric-wave, two-color compensative, as well as based on nonlinearity equation of emissivity spectral distribution. The temperature measurement errors of new technologies are lower than the same ones of known spectral, as well as classical energy and spectral ratio thermometry in 2,3; 11,7–20,0 and 6,1–7,6 times. Keywords: metallurgy of machine building, continuous optical temperature control, cupola furnace, arc furnace, classical and spectral thermometry.

Detoxification of lead and arsenic from galamsey polluted water using nano synthesized iron oxide from cupola furnace slag

Drinking of water polluted with heavy metals is a means by which heavy metals bio accumulate in the human body. The rise in galamsey (illegal mining) activities in Ghana has resulted in heavy metal pollution in most water bodies in the country. Above the permissible limits, these metals cause health issues such as cancer, brain damage, kidney damage and other respiratory diseases. Hence, a smart solution to this menace is urgently needed. In this study, iron oxides were recovered from cupola furnace slag by magnetic separation and froth flotation. The recovered iron oxide was modified using electrospinning with the aid of polyvinyl alcohol after which it was calcined and used as adsorbent to detoxify lead and arsenic from two galamsey polluted water bodies in Obuasi, Ghana. Samples of the adsorbent were characterized using X-ray Fluorescence (XRF), X-ray Diffractometry (XRD), Fourier Transform Infrared Spectrometry (FTIR), Scanning Electron Microscopy (SEM) and Brunauer-Emmer-Teller (BET) method. The highest recovery for iron oxide using magnetic separation was 99.42% and that of froth flotation was 90.64%. The recovered iron oxide used as adsorbent was composed 53.04% iron oxide, with major phases like magnetite, hematite, goethite and quartz. Moreover, the surface functional group were determined to be Fe–O and OH. Also, the calcined nano fibres which were spherical in shape with rough surfaces had a specific surface area of 1.1331 m2/g. The contaminated and detoxified water were also analyzed using Atomic absorption Spectroscopy (AAS). Both adsorbent (beneficiated iron oxide and calcined nano fibre) performed well in the adsorption process, with the recovered iron oxide having 97.33% maximum lead removal efficiency while an 81.00% maximum removal efficiency for arsenic. The calcined nano fibre had a maximum of 99.99% removal efficiency for lead and 88.40% maximum efficiency for arsenic. Additionally, the adsorption fits the Langmuirian isotherm model better than the Freundlich model, indicating mono layer coverage.

Effect of cupola slag as a coarse aggregate on compressive strength of concrete

The global exponential rise in natural resource consumption poses a serious problem, which is causing a shortage of these resources. As a result, research towards the efficient management and finding alternatives of conventional resources is gaining more importance. Investigating the utilization of industrial by-products in the construction industry can be considered as a potential solution in reducing the consumption of conventional construction materials. Steel slag is an industrial by-product which is generated in huge amount and disposed in the environment as a waste material. Various types of steel slag are produced depending on the furnace type used in the industry. Cupola slag is one such type of steel slag produced from cupola furnace,in the process of manufacturing cast iron. The potential of cupola slag as a partial replacement of coarse aggregate was studied in this paper. Physical and chemical characteristics of cupola slag were studied. The preliminary properties of cupola slag were found to be similar to the natural aggregates and could be incorporated into the concrete. The aim of the study is to observe the effect of the percentage increment of cupola slag on concrete. The slag percentage was changed in each mix design while maintaining other design parameters constant. The coarse aggregate is partially replaced by 30%, 35%, 40% and 50% with cupola slag without replacing the natural sand. All the mix proportions of designed concrete were studied for compressive strength at the age of 7 days and 28 days. The maximum compressive strength of 66.36 MPa was observed for 30% substitution on 28th day. It was found that, further increase in substitution causes a decrease in strength. The results indicate that cupola slag can be used in concrete efficiently up to 30% and can provide a promising solution for reducing industrial waste landfill, ensuring a sustainable environment.

Impact of Biocoke Utilization on the Cupola Furnace Operation and its Effect of CO<sub>2</sub> Reduction

Impact of Biocoke Utilization on the Cupola Furnace Operation and its Effect of CO<sub>2</sub> Reduction

Evaluation of hot deformation in foundry core sand using cupola furnace slag as additive

RESUMO Nesta pesquisa foi avaliado o efeito da adição de três tipos de escória de fornos cubilô na deformação a quente de núcleos de areia. Além da avaliação de distorção a quente, foram avaliadas propriedades como resistência a tração imediata e resistência a tração após 30 minutos. Comparativamente, avaliou-se para cada tipo de escória, misturas com a adição 8, 12, 20, 40 e 70% em peso de escória sobre uma areia de sílica da região sul do Brasil. Os resultados mostraram uma redução na resistência à tração imediata dos núcleos de areia, independente do tipo de escória utilizada. A adição de escória granulada de cubilô, devidamente processadas, reduziu a deformação máxima a quente dos núcleos de areia, observou-se também que deformação foi diferente para cada tipo de escória utilizada. De uma maneira geral, os melhores resultados de deformação máxima foram obtidos para as misturas com 70% de adição, seguidas das misturas com 40% de escória. A adição progressiva das escórias também reduz a taxa de deformação, sendo que as escórias verde e preta apresentaram redução de 58%. Os resultados obtidos no ensaio de distorção a quente mostraram um potencial de utilização da escória de cubilô para melhorar o desempenho dos núcleos de areia em relação a defeitos motivados pela expansão da areia de sílica.

Effect of Cupola Furnace Slag Addition on the Characteristics of Ordinary Portland Cement Blocks

Effect of Cupola Furnace Slag Addition on the Characteristics of Ordinary Portland Cement Blocks

Thermal analysis to investigate the effects of operating parameters on conventional cupola furnace efficiency

Background: Thermal analysis was performed on a conventional 6.5 m high dome with a 0.65 m diameter at Nigeria Railway Corporation. Energy and thermal analyses were performed on the furnace to improve efficiency and minimize energy losses in the system. Results: The energy efficiency recorded was 55%. The losses in the furnace amount to 45%, the highest value being the heat loss to the combustion gas at 34%. A parametric study was examined to see the effect of some design and operational parameters on furnace efficiency through energy savings and the study found a positive trend. The parameters include the flue gas temperature, the combustion air inlet temperature, the thickness, and the emissivity of the refractory wall. A decrease in the temperature of the flue gases increased the efficiency of the furnace to 73%, an increase in the air inlet temperature increased the efficiency of the furnace to 61%, and an increase in the thickness of the refractory wall increased the efficiency of the furnace. Oven to 56% and a decrease in emissivity of the refractory wall increased the efficiency of the furnace to 56%. Conclusions: The studied parameters were further combined and their net effect showed a possible increase in furnace efficiency from 55% to 78%. The maximum efficiency of 78% was determined with respect to the minimum/maximum estimated values of the parameters studied, as more metals are melted with the combined energy saved from a variation of these parameters. This implies that cupola furnace or similar furnace designers or operators should be guided on the preheating conditions, thickness, and emissivity of the refractory wall to be used with other parametric combinations to be adopted to ensure energy efficiency and improvement in such furnaces.

Beneficiation of Iron Oxides from Cupola Furnace Slags for Arsenic Removal from Mine Tailings Decant Water

Large volumes of ferrous metallurgical slags (FMS) are generated annually as waste materials from metal extraction, purification, casting and alloying processes worldwide. Some attempts have been made to use bulk FMS in metal precipitation and concrete works but little success has been achieved because of unstable precipitates and volume expansion of concrete structures. As a result, significant quantities of FMS are still disposed in landfills. This disposal leads to land conflicts and poor environmental practices. The present study focuses on the characterization and separation of iron oxide from selected bulk FMS (Cupola Furnace Slag - CFS) obtained from Ghana into constituent components for use as engineering materials. Quantitative X-ray diffractometry was used to determine the mineralogy of CFS. Iron oxide morphology and spot composition in the CFS were determined using scanning electron microscopy, combined with energy dispersive spectroscopy. The inductively coupled plasma-optical emission spectrometry was used to ascertain the chemical composition of CFS after acid digestion. Wet low intensity magnetic separation technique was employed for beneficiating iron oxides from the CFS. It is shown that the CFS is amorphous and consist of ferrous and non-ferrous material. Results of the investigation confirmed that ferrous materials in the slags can be separated using magnetic separation technique. The study further confirmed that fine grinding (- 75 µm) liberates the magnetic portions of the slag efficiently, and as such, they can be recovered using a low magnetic field. The recovery was 99.04 % and the concentrates obtained from the beneficiation process consist primarily of pigeonite, quartz, magnetite and jacobsite. The beneficiated concentrates have the capacity to adsorb arsenic from mine effluent. This study has demonstrated that, slags can be utilized as secondary resources rather than a waste.

Design and Fabrication of Economical Industrial Air Filter

The design and fabrication of an economical air filter is for an industrial cupola furnace in MIDC, Hingna. The purpose of an industrial filter is to remove unburned coal particles’ hazardous fumes and reduce NOX in the environment. The filtration system consists of a filter box that comprises four filter media which are placed vertically like a cartridge. The first media is manufactured like a frame containing a steel wool scrubber. This frame traps hot gases and large particles of smoke. The second frame contains a layer of blue silica gel that absorbs moisture present in polluted air. The third filter frame consists of activated carbon which has chemical properties for the adsorption of Carbon dioxide and Nitrogen dioxide gases. The last filter is HEPA (high-efficiency particulate air) filter, which is made from element paper. It can filter 0.3μm diameter of dust particles. Finally, we get the filtered air through the exhaust. This filtration system is effective in terms of cost, cleaning, and maintenance. The filters are easy to remove when the dust gets chocked in it, also clean easily with the help of a pneumatic gun or some dust cleaning system. This will be economical and easy to maintain.

Utilizing Artificial Neural Network and Multiple Linear Regression to Model the Compressive Strength of Recycled Geopolymer Concrete

Based on the heterogeneity of concrete constituents as well as variability in compressive strength over many magnitudes for various types of concrete, predictive methods for evaluating the compressive strength have now been given considerable attention. As a result, this research compares the performance of the Artificial Neural Network, ANN, in forecasting the compressive strength of geopolymer recycledconcrete (GPRC)based on selected pozzolans (Coal Fly Ash (CFA) and Rice Husk Ash (RHA)) at ages 7, 28, and 56 daysto the traditional Multiple Linear Regression, MLR. The compressive strength of GPRC-based CFAand RHA was determined using 65 concrete samples from eight different mixtures.The developed models were based on the experimental results, which used varying material quantities. The ANN and MLR models were built with eightinput variables: Ordinary Portland cement (OPC), RHA, CFA, Crushed granite (CG), Cupola Furnace Slag (CFS), Alkaline Solution (AS), Water-Binder Ratio (WB), and Concrete Age (CA), with compressive strength being the only predicted variable. Using MATLAB® code, approximately 75% and 25% of the input data were used for training and testing to develop an ANN model for predicting compressive strength, fcu.For ANN and MLR, the input data were trained and tested using the feedforward back-proportion and backward eliminationapproaches, respectively. Based on satisfactory performance in terms of means square error MSE, the most likely model architecture containing eight input layers, thirteen hidden layers, and one output layer neurons was chosen after several trials. According to the MLR results, only three input variables, CFA, CG, and CA, are statistically significant with p-values less than 0.05. R2= 0.9972, MSE = 0.4177, RMSE = 1.8201,for ANN and R2= 0.7410, MSE = 66.6308, RMSE = 290.4370, for MLR. The predicted results demonstrate the proposed model's dependability and computational forecasting capability. The findings of the study have the potential to help a wide range of construction industry in predicting the concrete properties and managing scarce resources.

Performance assessment of mechanical and durability properties of cupola slag geopolymer concrete with fly and rice husk ashes

Research into substituting recycled materials for cement and aggregates can yield beneficial natural resource conservation, waste management, cost savings, and reduced embodied energy in concrete. Hence, this research investigates the potential adoption of coal fly ash (CFA) and rice husk ash (RHA) as geopolymer binders to partially substitute cement in varying proportions up to 25%. However, cupola furnace slag (CFS) was also used as a partial substitute of crushed granite from 0% to 35% in steps of 5% in the production of geopolymer concrete (GPC). The selected geopolymer binders were synthesized using an alkaline solution. Workability, compressive strength, and rapid chloride penetration tests on fresh and hardened normal concrete (NC) as control and GPC containing CFS were evaluated at different water-binder ratios. The findings revealed that integrating 15%CFA, 20%RHA, and 30%CFS with w/b of 0.50 and 0.65 improved the workability by 180% and 105.7%, respectively, but compressive strength is significantly reduced. The findings further showed that combining 75%OPC, 20%CFA, 5%RHA, 100%RS, 20%CFS, and 80%CG results in optimal compressive strength of 19.68 N/mm2 and, 21.49 N/mm2 at 28 days and 56 days with w/b of 0.50, respectively, as contrasted to the lowest possible strength requirement. The Rapid Migration Test (RMT) was used to determine the chloride ions permeability in various concrete mixes. The results show that GPC produced with the combination of 15%CFA, 20%RHA 65%OPC, 30%CFS, and 70%CG with w/b of 0.65 is more durable and has higher chloride ion penetration resistance than most other mix proportions.

Development of Low-cost Smelting Reduction Process Using Cupola Furnace for Efficient Use of Inferior Grade Manganese Ores and Rejects

Development of Low-cost Smelting Reduction Process Using Cupola Furnace for Efficient Use of Inferior Grade Manganese Ores and Rejects

Behavior of the Fireclay Lining of a Coke Gas Cupola Furnace When Melting Cast Iron with Anode Scrappage in Electrolysis Production. Part 21

Behavior of the Fireclay Lining of a Coke Gas Cupola Furnace When Melting Cast Iron with Anode Scrappage in Electrolysis Production. Part 21

Performance of concrete made from cupola furnace slag and recycled concrete aggregate

Portland cement concrete (PCC) is an unquestionably flexible and valuable material for any nation's infrastructure and construction development. Nevertheless, the negative health impacts of cement production, the aggregate fraction of concrete, and the building supply shortage are some drawbacks of concrete use. Cupola slag (CS) and recycled coarse concrete (RCA) wastes from industrial processes, construction, and demolition sites are disposed of into the environment, resulting in pollution that threatens marine, agriculture, and public health. Therefore, CS and RCA as a binder and coarse aggregate in concrete production would help protect the environment. This study presents the outcome of an experimental investigation on (i) partial substitution of cement at percentage levels of 0% to 25% in steps of 5% with granulated cupola slag, (GCF); (ii) partially substitution of coarse granite from 0% to 50% in steps of 10%; with coarse cupola slag (CCS); and (iii) complete replacement of CG with recycled coarse aggregates and subsequently partially replaced with CCS from 0% to 50% in steps of 10%. The fresh and hardened properties of concrete, such as workability and compressive strength, were tested. The test results generally showed that the workability increases with an increase in percentage replacement. However, at 7, 14, 28, and 56 days concrete produced from the partial replacement of cement with GCF had the optimum compressive strength of 9.65 N/mm2, 15.85 N/mm2, 20.37 N/mm2, and 22.15 N/mm2 at 10% replacement. The strength, however, increased by 13.67%, 23.54%, 29.42%, and 25.42% compared to the control sample. Similarly, concrete produced from the partial replacement of CG with CCS gave the optimum compressive strength at 10% replacement with a value of 14.89 N/mm2 at 28 days. The compressive strength obtained from the complete replacement of CG with RCA was lower compared with the control samples at 7, 14, 28, and 56 days. It can be concluded that the concrete made with CS and RCA show a satisfactory development and consistency in strength as compared to control sample.