Waste foundry sand (WFS) is the by-product of the foundry industry, which is produced about 0.6 tons per 1 ton of foundry industry production. While it cannot be recycled or reused, it will be ...disposed of in landfills. Today, with increasing attention to environmental issues, the reuse and recycle of materials because of limited resources have been considered. Due to the desirable properties of WFS, many studies have been done on the properties and performance of its use in various industries, especially in concrete technology. The purpose of this paper is to conduct a bibliometric analysis of foundry sand research during the years 1971-2020. Various aspects, such as document types, languages, major journals, key countries, authors, and keywords, have been examined. The collaborations among authors and countries were constructed, visualized, and evaluated through the application of the social network analysis method based on co-authorship relations. Also, keyword cluster analysis has been performed using co-occurrence relations to discover the most prominent issues related to WFS. The results showed that the number of publications (TP) has improved significantly in recent years, especially in 2018-2020. It has increased from 1 in 1971 to 38 in 2020. The engineering subdivision with 33% has had the highest number of papers. Also, India, China, and the USA have the highest number of publications, respectively. Statistical data from the author keyword study showed that in general, papers can be classified into three categories in terms of subject: first, characteristics of WFS and its importance; second, the use of WFS in concrete and the study of mechanical and physical properties as one of its applications; and the third, investigation on environmental effects and damage caused by disposal and landfill of WFS and efforts to find solutions for recycling and reuse. The keywords “Waste Foundry Sand,” “Foundry Sand,” and “Compressive Strength” with a growth rate of 2700%, 1900%, and 1100%, respectively, are important topics in the field of WFS research.
•Properties of concrete with a combination of FS/RFA and FA/GGBS are studied.•FS concrete exhibits a higher slump than RFA concrete at the same replacement level.•25% RFA concrete has slightly higher ...compressive strength than conventional concrete.•25% FS and RFA concretes both exhibit similar elastic modulus to conventional concrete.•23% FA/47% GGBS concrete exhibits a higher strength than conventional concrete.
In recent years, the use of fly ash (FA) and ground granulated blast furnace slag (GGBS) as cement replacement materials as well as foundry sand (FS) and recycled fine aggregate (RFA) as sand replacement materials has provided an attractive avenue toward a green construction material for decreasing the effect of concrete and construction and demolition (C&D) waste on the environment. The behavior of concrete produced with a combination of FS/RFA and FA/GGBS is presented in this paper. 17 concrete mixes were prepared, and tests were undertaken to assess workability, density, compressive, splitting tensile and flexural strength, elastic modulus and water absorption of each mix. It is shown that an increase in the FS and RFA content up to 100% causes a decreased compressive strength of concrete. However, concrete containing RFA at 25% sand replacement experiences a slightly higher compressive strength in comparison to conventional concrete. Replacement of cement with FA at different levels has a negative impact on the concrete strength, whereas cement replacement with 23% FA and 47% GGBS results in a higher concrete strength in comparison to that of the companion cement-based concrete with the same sand replacement level. The results also show that replacement of sand with FS and RFA at up to 25% leads to a nearly identical elastic modulus compared to that of the conventional concrete. Although elastic modulus of FA mixes is lower in comparison to that of conventional concrete, GGBS and ternary (combination of FA and GGBS) mixes provide nearly close elastic modulus to conventional concrete. Sand replacement with FS at up to 50% in concrete results in a similar water absorption to the conventional concrete. It is shown that GGBS and ternary mixes experience a lower water absorption compared to the conventional concrete. These findings indicate that the mix design technology used in the present study offers a significant potential to produce concretes with a reduced environmental impact.
This article presents the findings of a study focusing on the gas generation of 3D-printed cores fabricated using binder-jetting technology with furfuryl resin. The research aimed to compare gas ...emission levels, where the volume generated during the thermal degradation of the binder significantly impacts the propensity for gaseous defects in foundries. The study also investigated the influence of the binder type (conventional vs. 3D-printed dedicated binder) and core construction (shell core) on the quantity of gaseous products from the BTEX group formed during the pouring of liquid foundry metal into the cores. The results revealed that the emitted gas volume during the thermal decomposition of the organic binder depended on the core sand components and binder type. Cores produced using conventional methods emitted the least gases due to lower binder content. Increasing Kaltharz U404 resin to 1.5 parts by weight resulted in a 37% rise in gas volume and 27% higher benzene emission. Adopting shell cores reduced gas volume by over 20% (retaining sand with hardener) and 30% (removing sand with hardener), presenting an eco-friendly solution with reduced benzene emissions and core production costs. Shell cores facilitated the quicker removal of gaseous binder decomposition products, reducing the likelihood of casting defects. The disparity in benzene emissions between 3D-printed and vibratory-mixed solid cores is attributed to the sample preparation process, wherein 3D printing ensured greater uniformity.
•Efficacy of dilute acidic solutions were evaluated for waste sand reclamation.•Mass balance of bentonite was performed for chemical reclamation process.•Reclaimed sand was assessed based on the clay ...content, strength, GFN, LOI, and ADV.•Running cost per ton of reclaimed sand is less than half the cost of fresh sand.•Field trials revealed that reclaimed sand can be used for core production.
The disposal of Waste Foundry Sand (WFS) poses a significant challenge for the foundry industry today, primarily due to its composition of metal oxides (Al2O3, Fe2O3, MgO, CaO, and Na2O) and sand. These metal oxides, categorized as loosely and strongly bound clays, are considered impurities in core production. This study proposes a chemical reclamation technique for WFS using fresh acid solutions or acidic industrial effluent. Experiments were conducted to remove the loosely and strongly bound clays from the WFS, optimizing parameters such as acid concentration, sand to acid loading, temperature, stirring speed, and reaction time to achieve optimal performance. The quality of the reclaimed sand was evaluated using various foundry standard tests, including determination of clay contents, compressive strength, Grain Fineness Number (GFN), Loss on Ignition (LOI), Acid Demand Value (ADV), and scanning electron microscopy. The reclaimed sand exhibited a loosely bound clay content of 1.5 %, oolitic content of 5.5 %, a grain fineness number of 55, a loss on ignition of 1.92 %, and an acid demand value of 1.5 ml/100 g of sand. Field trials demonstrated that the reclaimed sand can be effectively used for core production at an economical rate.
The EU's industrial sector discards about 18.9% of its energy as waste heat, much of which has the potential for recovery. This study addresses the challenge by focusing on the advancement of latent ...heat thermal energy storage (LHTES) using phase change materials (PCMs) encapsulated within industrial waste foundry sand (WFS). WFS, a problematic by-product, is repurposed as a supportive matrix for NaNO3 and solar salt PCMs, tailored for effective integration into high-temperature industrial processes. The paper provides a thorough mechanical and thermal examination of the WFS-salt PCMs, highlighting their improved thermal stability, performance, and compatibility with direct thermal energy systems. The composite PCMs demonstrated melting points well-suited for industrial waste heat applications and achieved an energy density of 542.0 ± 8.3 kJ/kg for NaNO3 and 516.0 ± 4.5 kJ/kg for solar salt, An experimental cascade PBLHS, based on these CPCMs, with a capacity of 262 MJ, designed to mimic an industrial heat source at 450 °C, was systematically tested to assess its energy density and efficiency over repeated charging/discharging and free cooling cycles. Its overall system efficiency is found to be 68.5%. These findings position WFS-salt PCMs as a promising and environmentally beneficial approach to enhance industrial energy efficiency and utilisation.
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•Novel use case for waste foundry sand (WFS) is presented.•Composite phase change materials (CPCMs) based on WFS and molten NaNO3/SS are presented.•CPCM energy density is 542 kJ/kg for NaNO3 and 516 kJ/kg for SS (25–450 °C).•A packed bed latent heat storage system based on WFS-CPCMs is presented.•The system with a capacity of 262 MJ has an overall efficiency of 68.4%.
Spent waterglass foundry sand (SwFS) is a bulk waste of the metallurgical industry containing at least 2–5 wt% of the waterglass layer without effective utilization. To this end, this paper proposes ...the disposal of SwFS as fine aggregates for MgO-activated slag materials (MASMs). Two types of SwFS subjected to different treating temperatures (100°C and 800°C) were prepared to investigate their effects on fluidity, compressive strength, pore structure, and micromechanical properties of MASM. The experimental results showed that the coated waterglass of SwFS played an important role in affecting the performance of MASM mortars. For SwFS subjected to 100°C, the coated waterglass could be partially dissolved and released into the surrounding paste to activate slag along with MgO. Compared with the group without SwFS, the resulting compressive strength (MPa) of mortars with SwFS was increased by 33.6–74.1% at all ages, and the average elastic moduli (GPa) of C-A-S-H were increased by 19.6%. In contrast, for SwFS subjected to 800°C, the coated waterglass can hardly be dissolved, which induced a complex interface in the microstructure of mortars, leading to the reduced compressive strength of mortars.
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•Sand mold study for metal casting using 6 types of sand and 3 types of binder.•Cerabeads 1450 and zircon sand exhibited the best flow properties.•Most strength, least loss on ...ignition obtained with modified sodium silicate binder.•Cerabeads 400 has the most permeability but least strength.•Test results can be used for mold material selection and performance comparison.
A good sand mold is an indispensable prerequisite to obtaining a good metal casting. Although sand casting is one of the oldest metal forming technique known to humans, it still has a lot to discover. In a bid to meet the ever-growing demand for quality, economics and increasing environmental restrictions, research is still ongoing to optimize for example the process of making the sand mold. This paper presents a comparative study of six different foundry sands for flowability using simple inexpensive apparatus and some quality parameters achieved by these sands when used with three different types of binder, two organic and one inorganic. The study aims to facilitate the choice of mold materials with a more extensive outlook into their characteristics through a serious of sand and mold tests. A good comparison of already existing materials provides a good reference point when novel materials are investigated. All the sands exhibited ‘good’ flow property according to the simple flowability tests done. However, not the same consensus for flowability rank is reached by all the flow tests. The mold quality tests reveal the strength, loss on ignition and permeability values achieved with each of the binder and sand combination which can also be used in mold material selection.
•Gathering a comprehensive dataset for the compressive strength of concrete with WFS.•Predicting the compressive strength of concrete using multi-objective ANN.•Using multi-objective multi-verse ...optimizaer in determining ANN architecture.•Specifying the crucial parameters on the compressive strength of concrete with WFS.
The amount of waste materials obtained from industries is increasing every day, which has been identified as one of the crucial issues in many countries. Waste foundry sand (WFS) is a by-product of the foundry industry, which can be used as a partial replacement for fine aggregate in concrete. The aim of this study is to predict the mechanical properties of concrete containing WFS using an artificial neural network (ANN) assisted by multi-objective multi-verse optimizer (MOMVO) algorithm. In the proposed model, both network error and complexity were considered as multi-objective optimization problems which were solved using MOMVO. To develop the proposed model, a comprehensive database including effective parameters on the mechanical properties of concretes were gathered and modeled in MATLAB environment. For compressive strength, splitting tensile strength, modulus of elasticity and flexural strength of concrete containing WFS, several optimal ANN models were achieved and the performances of the two selected models for each mechanical property were compared. The results showed the potential of acceptable accuracy of the developed ANN model assisted by MOMVO algorithm in estimation of the studied mechanical properties. Finally, a parametric study was carried out to investigate the contribution of each input variable on the mechanical properties of concrete containing WFS. The results inferred that the ratios of water to cement, fine aggregate to total aggregate, and coarse aggregate to cement had the most effect on the mechanical properties.
•Crushed limestone and waste foundry sand were employed in the fabricated matrix.•Using 10% of waste foundry sand as a partial replacement enhanced the mechanical strength properties.•The mixes ...showed a reliable performance under freezing-thawing cycles and less than 1 gm under abrasion.
Among the recent research interests in the construction section, Geopolymers, represent a rising trend due to their significant performance in terms of strength and long term properties. In this research, an attempt was conducted to examine the effect of using different filling materials and the effect of different NaOH concentrations on the properties of the resulted composites. Strength properties, physical properties, abrasion resistance, and freezing-thawing behavior were tested along with a microstructural characterization that included scanning electron microscopy (SEM) and X-ray diffraction (XRD). In general, the effect of including crushed limestone and waste foundry sand was beneficial in terms of the general properties of the fabricated specimens. Also, the microstructural analyses showed a compact matrix that could be considered in line with the obtained results from the other tests.
Owing to the tremendous increase of chemicals for agricultural practices, the quality of water has degraded significantly and requires inevitable attention. With this in mind, present work aims at ...treating Paraquat (PQ) contaminated water using Fe containing industrial waste as a catalyst via photo-Fenton treatment. Utilizing the industrially generated Fe rich waste by-products i.e., Fly ash (FA), Foundry sand (FS), Red mud (RM), and Blast sand (BS) as catalysts marks the novelty of the work since this idea of using waste for treating waste serves the dual purpose of environment remediation:first by treating wastewater and second by resolving the issue of solid waste disposal. In the present study, 25 mg/L PQ was subjected to both UV and solar radiations in the presence of FeSO4, FA, FS, RM, and BS as catalysts. The presence of Fe in the catalysts was verified using analytical techniques namely FTIR, FESEM-EDX, and their XRD was also analyzed. The system was further optimized for various parameters and results indicated maximum PQ degradation under UV radiations was attained in the order FeSO4 (73%) > BS (65%) > FS (46%) > RM (37%) > FA (14%) within 60 min which significantly increased with introduction of solar radiations to 83% for Fe salt and 76% for BS justifying the potential of using waste for treating waste. Further, to enhance the real-life utilization of industrial waste, Fe2O3/BS heterojunction (Fe-BS) was synthesized which along with leading to 88% degradation of PQ, also showed 82% COD removal indicating that the catalyst not only degrades the pollutant but also converts it into a lower toxic form. Further, the intermediates formed during the process were analyzed using LCMS.
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•Employing industrial solid waste for treating contaminated water.•Utilization of freely available solar energy for water treatment.•Fabricating cost-efficient water treatment system.•Engaging photo-Fenton treatment at natural pH of pollutant.•Analysis of intermediates formed in between the degradation process.
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