Incorporation Of Industrial Wastes Research Articles

Effect of brass slag particles on the microstructure and hardness of Al-Si alloy matrix composites

The current study investigated the effects of brass slag particles on the microstructure and hardness of Al-Si alloy (LM30) matrix composite. Stir casting was used to fabricate a composite with brass slag particles of finesize (i.e. 100–215 μm), coarse size(i.e. 215–350 μm) and three different concentrations of 3 wt%, 6 wt%, and 9 wt%. The dynamic shear force generated by stirring prevents brass slag particles from sinking into the melt which result in uniform particle dispersion throughout the melt. Optical microscopy analysis reveals a uniform distribution of reinforcement particles in cast composites, accompanied by silicon refinement. The findings suggest that the incorporation of industrial waste (brass slag as a reinforcement) in the fabrication process enhances microstructure and mechanical characteristics of composites. 9 wt% concentration of brass slag reinforced of fine size composite demonstrated an impressive ∼60.7% improvement in hardness compared to base alloy (LM30). It was also observed that theoretical density (ρth) and experimental densities (ρex) approximately 25% and 18.4% greater than that of the base alloy (LM30).

Towards sustainable construction: Performance evaluation of slag-cenosphere geopolymers under different NaOH concentrations

The incorporation of industrial wastes into construction materials, such as geopolymers, is highly desirable to improve their environmental impact. The choice of source materials, such as slag and cenosphere, and the amount of activator used significantly impact the properties of geopolymers. For instance, including high-reactivity precursors and optimizing activator composition may enhance mechanical strength and durability. However, no studies have evaluated the effect of cenosphere addition on the properties of geopolymer composites. This research study aims to unveil the synthesis of a binary geopolymer material by integrating slag and cenosphere as precursors, activated by sodium silicate (Na2SiO3) and sodium hydroxide (NaOH). Geopolymer composites were prepared to assess the impact of cenosphere addition (by substituting the slag with cenosphere in different percentages of 25, 50, and 75 %) and NaOH concentration (specifically 6 M, 9 M, and 12 M) on the material's properties. Additionally, one conventional mortar with a water-to-cement ratio of 0.5 was also prepared. Compressive strength, ultrasonic pulse velocity (UPV), electrical resistivity, water absorption, density, and thermogravimetric analysis were conducted. Results showed that increasing the cenosphere percentage increased the water absorption and decreased the compressive strength, UPV, electrical resistivity, and density compared to the geopolymer mixture with 100 % slag content. However, up to 50 % substitution of cenosphere, the geopolymer mix performed better than conventional mortar. Notably, results suggest a potential increase in CO2 uptake due to the addition of cenosphere, further enhancing the environmental performance of geopolymer composites. The findings of this study suggest the potential use of slag-cenosphere geopolymer as an alternative and sustainable construction material.

Paper mill wastes and biochar improve physiochemical properties and reduce heavy metals leaching risks in podzolic soils

Background: The incorporation of industrial wastes, such as wood ash and paper sludge, as soil amendments is vital for both environmental sustainability and agroecosystem productivity. Herein, we evaluated the effects of wood ash and paper sludge alone and in combination with biochar on the physicochemical properties and heavy metal leaching risks in podzolic soils. Methods: The treatments included limestone (control), wood ash, paper sludge, wood ash+paper sludge, limestone+biochar, wood ash+biochar, paper sludge+biochar and wood ash+paper sludge+biochar, arranged in a 4 × 2 factorial design with three replicates. The Hydrus-1D model was employed to simulate the water movement under these soil amendments using leaching colums. Results: Overall, wood ash, paper sludge and biochar application significantly increased the pH of amended soil compared to control. Paper sludge amended treatments alone or in combination with biochar significantly decreased bulk density (8%–17%) and increased the total porosity (14%–25%). While biochar addition to wood ash and paper sludge significantly reduced the concentrations of Cd (by 6.42%), Co (by 10.95%), Cu (by 11.76%), Pb (by 30%) and Ni (by 3.75%) in the collected leachates. The treatment paper sludge + biochar was found to be the most effective treatment to retain the heavy metals, with maximum plant available water (0.28 cm3 cm−3) and field capacity (0.36 cm3 cm−3) compared to control treatment. The predictions from Hydrus-1D showed that paper mill wastes with biochar has a significant potential to increase the volumetric moisture contents of amended podzolic soil, with the simulated leaching times and saturation levels closely aligning with the measured values. Conclusion: paper sludge + biochar treatment showed improved soil physicochemical properties and displayed lower heavy metals than allowed limits to be used in soil. Further, experiments are needed to assess the effects of papermill waste products on podzolic soil properties under variable field conditions.

Compressive constitutive behavior of steel fiber reinforced geopolymeric recycled aggregate concrete: Experimental investigation and analytical model

With the incorporation of industrial wastes and recycled concrete aggregate (RA), steel fiber reinforced geopolymeric recycled aggregate concrete (SFR-GRAC) can ensure both high performance and environmental benefits simultaneously. As a green concrete, SFR-GRAC is promising for practical engineering applications and its constitutive behavior needs a systematical study. This paper presented an experimental investigation on the stress–strain behavior of SFR-GRAC under uniaxial compression, focusing on the effect of RA substitute rates (25%, 50%, 75% and 100%) and steel fiber (SF) volume fractions (0.5%, 1.0% and 1.5%). The failure pattern, compressive strengths, stress–strain curve and corresponding characteristics, as well as energy absorption capacity were studied. The results show that the addition of SF improves the failure pattern and specimen integrity, as well as the mechanical properties in terms of peak stress, peak strain, elastic modulus and toughness due to the fiber crack-bridging action. The compressive strength and elastic modulus of GRAC are deteriorated with the use of RA, except that the decreases are less pronounced when the RA contents are below 50%. Moreover, the negative impact induced by the inclusion of RA can be alleviated by the addition of SF and the activation of alkali-activator as the rehydration of cement particles in old pastes in RA. Finally, based on a comprehensive analysis of the test results in current study and literature, empirical constitutive relations are established to model the stress–strain responses of SFR-GRAC with various RA and SF contents under axial compression, and model predictions show close agreements with test results.

Mechanical and Fractured surface characterization of epoxy/red mud/fly ash/ aluminium powder filled hybrid composites for automotive applications

In recent decades, one can observe a great increase in the replacement of traditional materials with polymer composites in high-strength and lightweight applications. High fuel consumption by automobile and aerospace vehicles built from legacy alloys has been a great challenge to material engineers. This has called for researches into lighter material development of the same or even superior mechanical properties to the existing materials in this area of applications. In the present study, epoxy based simple and hybrid composites were prepared with the incorporation of industrial waste as fillers at different weight percentages. Effect of filler type, combination and its concentration on mechanical properties such as tensile, impact and flexural strength were investigated. SEM analysis was carried out for fractured surfaces of composites, wherein minor voids, crack initiations and filler pullouts were seen indicating the necessity of coupling agent addition for still better performance. Among hybrid composites, epoxy/fly ash/red mud/aluminium powder (91/6/1.5/1.5 wt%) has showed the highest ultimate tensile modulus, flexural strength and hardness value compared to other composites under study.

Incorporation of Industrial Waste in the Development of Artificial Coating

Incorporation of Industrial Waste in the Development of Artificial Coating

Influence of a LAS-based modifying admixture on cement-based composites containing steel slag powder

The incorporation of industrial waste and by-products in cement-based composites has been widely studied and has a high potential for use, contributing to reducing environmental impacts. Also, the use of biodegradable, low-cost, and sustainable admixtures can provide considerable physical and economic advantages to cementitious materials. This work presents a study on the interactions of a modifying admixture based on Linear Alkyl Benzene Sodium Sulfonate (LAS) and steel slag powder (SSP) in the properties of cement-based composites. A two-level two-factor face-centered composite design (CCD) has been employed with response surface methodology (RSM) for modeling. The effect of the studied parameters (0–1.0% LAS and 0–50% SSP) on mortars' consistency and mechanical strength was evaluated. The separated and combined effects of SSP and LAS on hydration kinetics and the formation of hydrated products were investigated through ultrasonic pulse velocity (UPV) variations and X-ray diffraction (XRD) analyses. Also, fragments of mortar specimens were observed using scanning electron microscopy (SEM). For the studied ranges, increasing SSP and LAS contents increased the spread up to 22% and reduced the mechanical strength up to 57%. Both LAS-based admixture and SSP delayed the setting time, influencing the hydration kinetics. Mortars produced with the LAS-based admixture showed air incorporation, evidenced by the appearance of pores with spherical shapes. Results of RSM did not indicate interactions between the effects of SSP and LAS, and the SSP was the component that led to the most significant impacts.

Influence of the concentration of recycled glass on the technical-ceramic properties of a paste formulation for the manufacture of tiles

In industrial processes and human activities, a large amount of waste is generated, whose control or treatment is one of the most important problems today, mainly due to the limited availability of adequate places for its disposal, which generates a large accumulation of these and therefore contamination. In recent years, work has been carried out on the reuse of this waste, where its recycling and use in other sectors of the industry is contemplated.
 The incorporation of industrial waste and recyclable materials has turned out to be an alternative of interest in the industry, which leads to a considerable reduction of the negative impact on the environment. Therefore, this project intends to carry out a study on the reuse of recycled glass, in order to determine possible applications as a raw material for the ceramic industry.
 A physicochemical characterization will be carried out on these waste materials by means of different solid state techniques such as: X-ray fluorescence and X-ray diffraction, in order to determine their main characteristics and then incorporate them into the formulations of ceramic pastes and thus being able to analyze their behavior and influence on the technical-ceramic properties of the products obtained, which would make it possible to assess the potential for industrial use of these residues as raw material in the production of competitive ceramic materials.

Addition of Ornamental Rock Residues on Ceramic Blocks: Physical and Chemical Analysis

The incorporation of industrial waste in cementitious materials is an alternative for its adequate disposal. Among the residues that do not yet have adequate disposal are the residues created by the ornamental rock industries. In this context, this work aims to identify and characterize clays of the region where the ornamental rock industry is dominant and to verify the performance of the ceramic masses with the incorporation of the marble and granite residue. Physical and chemical characterization tests were performed on both clay and residues. After the identification of the two best clays, ceramic masses were prepared where it was possible to evaluate the performance of the clays with each of the residues in incorporations up to 20 wt.%. The results indicated that CI-A with 15 wt.% marble incorporation obtained the best performance.

Mechanical and tribological characterization of industrial wastes reinforced aluminum alloy composites fabricated via friction stir processing

Abstract The fabrication of particulate reinforced metal matrix composites via melt based processes poses issues like aggregation, wettability and formation of detrimental phases which may severely affect their performance. Recently developed solid-state process i.e., friction stir processing (FSP), is an efficient fabrication technique to counter the limitations of melt based processes. However, the incorporation of industrial waste in the metal matrix by using friction stir processing is rarely reported. Thus, the present investigation was carried out to reinforce the particulate type industrial waste in cast A356 alloy by friction stir processing. The performance of the fabricated composites as well as the as-cast A356 alloy was assessed through mechanical and tribological characterization. It was observed that FSP resulted in the eradication of porosity, fragmentation of α-Al dendrites, breakage and redistribution of Si particles, and grain refinement. A fair homogeneous distribution of reinforcement was observed in stir zone (SZ) with negligible aggregation of particulate reinforcement. The particle/matrix interface was free from any detrimental phase. The improvement in strength, ductility, and wear resistance was observed as compared to as-cast A356 alloy which was attributed to the microstructural changes that occurred during FSP, and the efficient reinforcement of particles via FSP.

Performance evaluation of asphalt micro surfacing – a review

In spite the fact that micro surfacing receives accolades by researchers of being the most cost-effective, environmentally friendly, and functionally viable pavement preventive maintenance amongst the various asphalt surface treatments (AST). However, there has not been a universally standardised mix design, acceptable material type, compatible polymer-binder combination, laboratory-field correlational performance tests, and its field dependency performance indicators. The requirements set by the International Slurry Surfacing Association (ISSA), Malaysian Jabatan Kerja Raya (JKR-public works department) and American Society for Testing and Materials (ASTM) are stated to be guides. This study brings to fore the challenges, methodologies adopted and successes recorded towards solving the aforementioned concerns by various researches globally from existing literatures with emphasis on material-type effects, mix design methodology, serviceability/environmental performance, incorporation of industrial wastes and emulsion-polymer compatibility amongst others in micro surfacing. Hence, the contents of relevant published journal articles, theses, academic and industrial reports published within the last two decades (1979 - 2019) that met the selection criteria aforementioned were critiqued. Result indicated improvement in key pavement surface functional performance parameters as a function of enhanced polymer(s) used in improving desired performance, type of aggregate and its gradation, pre-treatment condition and ultimately emulsion type. However, there is a lack of total consensus on the mix design, even though polymers are unanimously agreed by researchers to improve performance. Future advances in micro surfacing should focus on the use of industrial wastes, synthetic material and especially by-products from industrial processes.

Indirect Tensile Behaviour of Fibre Reinforced Alkali-Activated Composites

There are currently still some sustainability-related issues that need to be tackled within the construction sector. Namely, cement production is accountable for nearby 5% of the worldwide total CO2-eq release. Therefore, environmentally viable and economically sustainable solutions need to be pursued in order to mitigate the use of Portland cement. The incorporation of industrial waste in concrete compositions, such as fly ash (from coal combustion in power stations) is a feasible alternative. The properties of these residues may be enhanced through alkaline activation, which is able to yield aluminosilicate-based materials with excellent physico-chemical properties. Nonetheless, these materials exhibit a brittle behaviour. Therefore, the present work addresses the study of alkali-activated composites reinforced with sisal fibres. For that purpose, alkali-activated Class F fly ash was mixed with natural fibres and the composite mechanical behaviour was assessed through both indirect tensile and compressive tests. Four different fibre contents, in wt % of fly ash (0, 0.2, 0.6 and 1%), two fibre lengths (13 and 50 mm) and four curing periods (14, 28, 56 and 112 days) were considered. Results confirm that the post-cracking response of these composites was improved with the inclusion of sisal fibres. In general, higher residual tensile strengths and dissipated energy were observed for the lengthier fibres, i.e., 50 mm.

Incorporation of industrial wastes as raw materials in brick's formulation

This article presents a case study conducted as an experiment with the incorporation of different types of industrial waste in brick manufacturing process in laboratory scale. The main objective of this work is to incorporate large amounts of different types of waste as raw material in brick's formulation. Three types of wastes were mixed with clay: automotive industry waste sludge containing heavy metal concentrations; glass waste, from a galvanic plant, mainly consisting of glass microspheres; and wood ash, from the ceramic burning furnace. The formulation's materials were analyzed by X-ray diffraction, X-ray fluorescence and electronic microscopy. The dried samples were milled separately and then dry mixed. Water was added to the mixture in order to contribute to the compaction process. The samples were dried and then burned at temperatures similar to those used for brick firing furnace. The obtained ceramics were analyzed for their retraction and then submitted to flexural strength testing. Samples obtained value above 4 MPa were approved. Among the samples tested, the formulation that showed higher flexural strength was chosen. It was prepared sufficient sample to perform the solubilization and leaching tests. For tests, the samples were reduced to dust. The results of such analyzes did not identify the presence of elements described in the initial samples' formulation. Morphological analysis was performed using scanning electron microscopy. Tested sample showed glassy characteristic of material that has been sintered during the firing process. This effect is also a proof that the waste identified in initial sample's formulation were inerted. Obtained results characterizes that the tested formulation can be considered as an alternative for bricks manufacturing with incorporation of industrial waste and an activity non-hazardous to the environment.

A STUDY FOR SUITABILITY OF QUARRY DUST FROM DIFFERENT MINERALOGICAL SOURCES FOR REPLACEMENT OF FINE AGGREGATE

Incorporation of industrial waste in concrete. A number of studies on sustainable use of various type of quarry dust in concrete as a partial replacement of sand had been performed. In this the influence of three different types of quarry dust Granite, Limestone and dolomite (confirming to zone II of IS: 383) was studied taking the ratio of coarse aggregate, cement and water as fixed. Test for mechanical and durability properties of concrete were performed. Results shows that sample concrete with Granite as partial replacement of fine aggregated provide more compressive strength after 28 day curing, than other two mixes. The effect of shape and texture increases the interlocking of particles meanwhile reduces the workability of concrete. For same slump of concrete super plasticizer are to be used.

Assessment of the Technological Properties of High Temperature Fired Clayey Ceramics Incorporated with Glass Waste

The incorporation of industrial wastes into clayey ceramics used in civil construction is becoming a worldwide procedure not only to provide an environmentally correct destination for the waste but, in some cases, to improve the ceramic properties. The objective of the present work was to evaluate the effect of incorporation of a glass powder waste from decontamination process of fluorescent lamps into clayey ceramics. This evaluation was performed based on the technological properties of water absorption, linear shrinkage ad flexural strength. The properties evaluation was complemented by optical microscopy structural observation. The glass waste was incorporated in up to 30 wt% and specimens were uniaxially pressed at 20 MPa and fired at a relatively higher temperature of 1000°C. The results confirmed a substantial improvement of both the water absorption and the strength with glass waste incorporation into clayey ceramics.

Estudo das reações alcalis-sílica associadas ao uso da lama vermelha em argamassas colantes e de revestimento

A incorporação de resíduos industriais em matrizes cimentícias, com o objetivo de inertização, é uma alternativa de reutilização que tem sido bastante estudada nos últimos anos. No presente trabalho, estudou-se a lama vermelha, resíduo sólido gerado no processo de beneficiamento da bauxita e que, devido a seu elevado pH, é considerado "perigoso". Apesar do uso deste resíduo ter sido reportada em trabalhos anteriores, algumas patologias podem estar associadas à sua utilização, devido à elevada concentração de íons alcalinos (principalmente o sódio), favorecendo as reações álcalis-sílica (RAS) e às dificuldades de moldagem (reologia) devido à elevada finura deste resíduo. Apesar destes prováveis problemas provenientes do uso indiscriminado da lama vermelha como adição às argamassas e concretos, ainda são poucas as pesquisas que os contemplam, sendo este o foco do presente trabalho. Foram verificadas as propriedades reológicas das argamassas, utilizando um reômetro e a avaliação da RAS, de acordo com as normas ASTM C 1260-07 e NBR 11582. Os resultados obtidos foram bastante satisfatórios quanto ao comportamento das argamassas frente à RAS, apesar da elevada concentração de álcalis na lama vermelha, com grande influência reológica.

Análise dos gases poluentes liberados durante a queima de cerâmica vermelha incorporada com lodo de estação de tratamento de água

Diante dos problemas ambientais apresentados nas últimas décadas, a preocupação com a emissão gasosa intensificou-se consideravelmente. A indústria de cerâmica vermelha busca alternativas de preservação das matérias-primas naturais utilizadas, as argilas comuns, além de beneficiar o custo de produção. Uma alternativa viável é a incorporação de resíduos industriais à massa argilosa. Isto também contribui para diminuir o impacto ambiental negativo causado pelo lançamento desses resíduos no ambiente. No entanto, pouca atenção tem sido dada à emissão dos gases poluentes liberados durante a etapa de queima desses novos produtos cerâmicos. Neste trabalho, foram preparadas três massas argilosas contendo 0, 15 e 100% de lodo de estação de tratamento de água (ETA). As composições química e mineralógica do lodo foram determinadas. Corpos cerâmicos preparados por prensagem foram queimados entre 150 e 1100ºC. A emissão dos gases liberados durante a queima foi analisada pela técnica fototérmica. Constatou-se em relação à massa argilosa pura que a incorporação de lodo de ETA provocou um aumento significativo na emissão de CH4 e CO2.

Using marble and granite rejects to enhance the processing of clay products

The heterogeneity of traditional clay-based materials accommodates a variety of waste products compositions with little sacrifice of the final product properties and a much welcome relief on waste disposal concerns. Hence, the incorporation of industrial wastes or sub-products in bricks and tiles is becoming common practice. However, the continued depletion of natural resources throws new light on the potential use of some industrial wastes and natural sub-products as full-fledged alternative ceramic raw materials.This work shows the changes in properties of an industrial red-clay-based mixture, already in use in the production of floor tiles, due to additions of an ornamental stone cutting reject (marble and granite). Samples containing up to 30 wt.% reject were uniaxially pressed and sintered in air in an electric furnace (1100–1150 °C, for 2 h). The results obtained (X-ray diffraction and fluorescence, thermal analysis, firing shrinkage, water absorption and mechanical strength), explain the effect that the marble and granite reject additions have on the clay mixture behaviour and show how the properties of the sintered red-clay products can be improved, with the possibility of using lower firing temperatures.