The present study modifies the sorption isotherm for simulating the influences of initial pH and temperature variations on the cadmium sorption from contaminated water using waste foundry sand based ...on Langmuir, Freundlich, and Temkin models. Results proved that the Langmuir expression is able to adopt these effects by relating sorption capacity and affinity constants with pH and temperature of aqueous solution through exponential relationships (determination coefficient = 0.9375). The present model is assumed that the sorption process occurs through acidic functional groups and this is consistent with FTIR outputs. Interaction of cadmium/WFS is found to be exothermic by thermodynamic analysis.
Wettability alteration can occur at different stages during the producing life of a reservoir. Oil recovery from oil-wet reservoirs can significantly be increased by altering its wettability from an ...oil-wet to a strongly water-wet condition. Chemical agents such as surfactants are known as wettability modifiers in oil-wet systems. More recently, nanofluids prepared by dispersing nanoparticles in several liquid agents have been considered as potential wettability modifiers. In this work, the effectiveness of alumina-based nanofluids in altering the wettability of sandstone cores with an induced oil-wet wettability was experimentally studied. Eight nanofluids with different nanoparticles concentration, ranging from 100 ppm to 10000 ppm, were prepared by dispersing alumina nanoparticles in an anionic commercial surfactant. The effect of nanofluids on wettability alteration was investigated by contact angle and imbibition tests, and it was shown that designed nanofluids could significantly change the wettability of the sandstone cores from a strongly oil-wet to a strongly water-wet condition. Imbibition tests also allowed identifying the effect of nanoparticles concentration on the suitability of the treatment for enhancing the imbibition process and restoring the original core wettability. Results showed that the effectiveness of the anionic surfactant as wettability modifier could be improved by adding nanoparticles in concentrations lower or equal than 500 ppm. The best performance was achieved when a concentration of 100 ppm was used. Additionally, a core displacement test was carried out by injecting in a sand pack a nanofluid prepared by dispersing alumina nanoparticles in distillated water. The treatment was effective in altering the sand pack wettability from an oil-wet to a strongly water-wet condition as indicated by a significant reduction in the residual water saturation and a displacement to the right of the oil relative permeability curve and the crossover point.
The sustainability of using industrial by-products for the construction of landfill cover was determined using Life Cycle Assessment (LCA). LCA was carried out on four materials: sand- bentonite mix, ...red earth- bentonite mix (amended soil), Waste Foundry Sand (WFS)- Bentonite mix, and WFS- marine clay mix. The former two are commonly used cover soils and the latter two are alternative materials proposed. Environmental impacts based on the extraction of resources, processing, transportation to the site, and site preparation were considered using the ‘cradle to site’ approach. Analysis was carried out in OpenLCA software using the ReCiPe (H) Midpoint method of impact assessment. Required data for analysis was taken from the Ecoinvent database supplemented with inputs from a field survey. The use of WFS in landfill cover systems was found to be sustainable using LCA studies when compared to conventional materials.
Industrial waste has rapidly increased day by day due to the fast‐growing population and usage of products, which dumps unscrupulously, resulting in environmental pollutions. Waste foundry sand (WFS) ...is one of the industrial solid wastes. River sand is generally used in concrete as a fine aggregate, which is limited (scant), and river excavation for sand leads to environmental deterioration. To resolve these problems, a study was performed on WFS as a partial substitution instead of natural sand in concrete. The effects of WFS on concrete performance were assessed through durability and mechanical performance. The results from experimental tests show that, compared to concrete blends with WFS up to 30% substitution, the control mix strength was only 7.6% (28 days) higher, and this improvement is not too high. In the same manner, concrete mixtures that contain WFS up to 30%, and their durability properties were somewhat same to blank max (control). Test results showed that WFS with a substitutions ratio up to 30% can be successfully used in concrete without disturbing its durability and strength properties.
Abstract
The worlds demand on aggregates in construction is rapidly increasing from last few years, reason is mainly due to drastic economic growth of the Nations like Brazil, China, and India. ...Basically, this growth inspires the construction development and destruction activities. This study expresses the state of art of review on research of the industrial wastes which are polluting the environment. During the process of manufacture of several proportions and grades of concrete, non-conventional materials such as foundry sand from metal forging industry and tile dust produced by the tile industries were used to replace fine aggregate partial replacement of 10% - 50%, by weight of fine aggregate. It is found that compressive strength and flexural strength were increased up to 20% replacement of used foundry sand and 10% replacement of tiles dust with natural sand. Since the thickness of pavement slab is reduced, the cost of pavement construction is reduced almost 15% and 22% respectively for both type of alternative concrete mixes. Reuse of waste materials as a partial replacement of fine aggregate in concrete helps to achieve eco-friendly and sustainable development. Quarry dust is a flowable material used for ecofriendly waste for where the grade of conventional concrete is prepared. The mix of nano silica and GGBS with concrete (50 % GGBS, 46% OPC, and 4 % Nano Silica). The effects of reactive silicate and process variables like sodium content and molarity on the alkaline activation of various Nano clays and GGBS are investigated. Considering all the properties and materials partial substitution of 40% copper slag with fine aggregate is nearly equal to the strength of the conventional concrete. Among all other findings foundry sand and quarry dust of 20% and 10% proportions are used as a substitutional material in concrete got achieved adaptable strengths. In porous dam structures bentonite with high water cement ratio with aggregates produces flexible material used as a permeable layer.
The demand for natural aggregates (river sand) is increasing day by day, leading to the destruction of the environment, a burden that will be passed on to young people. Further, wastes from various ...industries are being dumped in landfills, which poses serious environmental problems. In order to ensure sustainability, both the issues mentioned above can be solved by utilizing industrial waste as aggregate replacement in the concrete construction industry. This research is done to find out the results using two substances viz., waste foundry sand (WFS) and coconut shell (CS) substitute for river sand and coarse aggregate. Many researchers have found the maximum benefits of substituted substances used in cement, which has material consistency. This current observation explores these strong waste properties of waste-infused concrete and cement, which experience shrinkage from drying out. The replacement levels for waste foundry sand were varied, between 10%, 20%, and 30%, and for CS, it was 10% and 20%. The experimental outcomes are evident for the strength, which increases by using WFS, whereas the strength decreases by increasing the CS level. The concrete that experiences shrinkage from drying out is included in the waste material, showing a higher magnitude of drying shrinkage than conventional concrete.
This study seeks to present a sophisticated artificial intelligence (AI) framework to model the compressive strength (fc′) of concrete containing waste foundry sand (WFS), with the aim of minimizing ...the need for time‐consuming laboratory tests and skilled technicians. For this purpose, artificial neural network (ANN) is hybridized with two metaheuristic algorithms—particle swarm optimization (PSO) and ant colony optimization (ACO) to predict the fc′ of 340 samples containing WFS collected from the literature. Results indicated that the ACO + ANN model showed the best performance with the Pearson coefficient of 0.9971, mean absolute error of 0.0221 MPa, and root mean squared error of 0.7473 MPa. The values of prediction errors exhibited that more than 90% of them in the ACO + ANN model fall within the range of (−1.5 MPa, 1.5 MPa), while this range for the PSO + ANN and traditional ANN models was obtained as (−3 MPa, 3 MPa) and (−4 MPa, 4 MPa), respectively. Furthermore, the proposed ACO + ANN model predicted the fc′ in the range of 5.24–54.48 MPa. Besides, the results indicated that the water‐to‐cement ratio, cement strength class, and cement content had the most significant impact on the fc′ of WFS‐containing concrete. Finally, a comparison was made between the proposed ACO + ANN model and four other AI models recently proposed in the literature, in which the performance criteria demonstrated that the proposed ACO + ANN model outperformed the models in the literature.
This review critically evaluates the potential of Waste Foundry Sand (
WFS
) as a substitute for fine aggregate in concrete, conducting a comparative analysis of its physical and chemical properties ...against those of natural sand. The study synthesizes findings from various research experiments to determine concrete's most effective
WFS
replacement percentage. It compiles and analyzes data on how different
WFS
ratios affect concrete's mechanical properties, including modulus of elasticity and compressive strength. The review also consolidates research on the impact of
WFS
on concrete's workability, density, and flowability. A key finding is that
WFS
, categorized as a non-hazardous waste, possesses a diverse particle size distribution, rendering it suitable for recycling in various industrial applications.
The study identifies that a 20%-30% replacement of
WFS
in concrete significantly improves properties such as voids, specific gravity, and density. However, it is essential to note that exceeding a 30%
WFS
replacement can result in increased carbonation depth and decreased resistance, primarily due to sulfur trioxide (
SO
3
). Further observations indicate that incorporating higher levels of
WFS
in self-compacting concrete reduces its flowability and increases water permeability. Moreover, the review highlights the regulatory and classification challenges associated with using
WFS
, particularly its classification as waste, which hampers its widespread adoption in construction. In conclusion, the study recommends implementing End-of-Waste (
EoW
) regulations to facilitate sustainable recycling and environmental protection. Additionally, it includes a bibliometric analysis of foundry sand research spanning from 1971 to 2020, providing a comprehensive summary of the field's historical and recent developments.
The use of industrial by-products and waste materials in concrete opens a whole new range of possibilities in the reuse of materials in the building industry. In this research study, concretes were ...made with chemical foundry sand (QFS) and green foundry sand (GFS) as substitution for raw sand. Also Electric arc furnace slag (EAFS) and blast furnace slag (BSF) were used as substitution for coarse raw aggregates in 25%, 50% and 100% of concrete production. Two concrete production stages were carried out. In stages 1 and 2, slump test and compressive and tensile splitting strengths and modulus of elasticity were determined. Due to adequate properties of all concretes found in stage 2, length change (during 56
weeks), sorptivity and high temperature exposure evaluation were also determined. The tests results obtained from concretes produced in stages 1 and 2 were compared with those of conventional concrete (CC) and the adequate use of the by-products for concrete production was verified.
PDF
