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Cold mix asphalt (CMA) technology is the most sustainable technology (green) available for the construction of flexible pavement to date, owing to the lower production temperatures involved. The present research investigates different fillers such as cement, fly ash (FA), and Stabil-road (SR) in different proportions ranging from 0 to 3% (1% increment). One control CMA with 1.5% water content and 6.6%asphalt residue and nine mixes with variable filler contents were prepared and tested according to the standards. The prepared mixes were tested and analyzed for mechanical properties namely Marshall stability, indirect tensile strength, resilient modulus (Mr), and abrasion loss. The stability of the CMA with 3% cement was 22% higher compared to the control CMA. Improvements in strength were observed with the inclusion of filler in the cold mix. The cold mix bituminous macadam (CMBM) is used for low-volume roads with mineral fillers, and it is a type of CMA, but using FA and SR, the strength and workability of the CMBM mix can be improved, and the mineral filler can be replaced by industrial waste. Significant reductions in production temperature and improved service life are some of the study's outcomes. It is a significant study because it reduces the asphalt production temperature and increases the pavement service life. It reduces energy loss during the construction of road pavement. Furthermore, the mechanical properties of the designed CMA depend on the mixing of aggregates, prewetting water content, emulsion, curing time, and pulse repetition periods. [ABSTRACT FROM AUTHOR]

Fouling in convective parts of boilers is typical of the deposition of solid particles and condensable inorganic vapours. Particle sticking is caused mainly by gravity, adhesion, or the presence of a sticky liquid film of condensed vapours. Aside from the local conditions, particle properties and size determine whether they are sticking on the surface. This work focuses on simulations of particulate matter fouling of cooled tubes by fly ash produced by the combustion of industrial waste and sewage sludge mixture. Boundary conditions including the flue gas and particle flow rate are derived from combustion tests. Particle properties and size distribution are obtained from literature. The goal is to provide a basis for further modelling of the development of large deposits in tube bundles observed during a test on the experimental facility. Neither the combustion nor fly ash development is modelled. Their transport and deposition are simulated. Fixed boundary conditions are set for both the particulate and gas phases. The influence of already deposited particles on the surface mechanical properties and roughness is included to capture their deposition. The fly ash particles are considered completely solidified, considering the low flue gas temperatures on the facility inlet. [ABSTRACT FROM AUTHOR]

The pre-eminence of concrete as the constitutional material used for rigid pavement construction has emanated through the millennia thereby amplifying the concern associated with its adverse effect on the environment. In this context, geopolymer concrete not only proposes a sustainable solution but also addresses the problems associated with extensive industrial waste generation and its imprudent disposal. This study aims to highlight the relevance of fly ash (FA) and red mud (RM) as geopolymer synthesizing source materials for pavement quality concrete (PQC). Investigations were designed to study the effect of varying replacement levels of FA (10%, 20%, 30%, and 40%) with RM in conjunction with different concentrations of sodium hydroxide in terms of molarity (10 M, 12 M, 14 M). The specimens subjected to ambient curing and oven curing at 60 °C were tested for compressive strength, flexural strength, and split tensile strength. Results portray that in the case of ambient cured FA-RM specimens, the highest compressive strength and flexural strength that could be achieved were 31.5 MPa and 4.32 MPa, respectively. Thereby, indicating inadequate strength development as per the requirements of PQC, even at a higher concentration of sodium hydroxide. Moreover, replacing FA with RM is mostly not effective at replacement values greater than 20% in both compression and tension. Furthermore, a defined study for assessing durability properties was also conducted by immersing the specimens in a 5% sulfuric acid solution. 11.46% and 7.25% reduction in compressive strength of control mixes was observed for specimens corresponding to 10 M and 14 M respectively, thereby substantiating decreased strength loss at higher molarity. [ABSTRACT FROM AUTHOR]

In the context of ongoing rapid industrialization, the increasing deposition of industrial waste has arisen as a persistent global challenge, necessitating immediate attention and subsequent implementation of sustainable remedies. This study convenes on the efficacy of industrial wastes, namely fly ash and ground granulated blast furnace slag, as geopolymer concrete synthesizers in conjunction with the incorporation of reclaimed asphalt pavement (RAP) aggregates as a replacement for natural coarse aggregates varying over 25% to 100%. Under 7 days of ambient curing, employing 14M NaOH and a 50% RAP replacement, the mix achieved significant strengths of 41.80 MPa in compression and 4.72 MPa in flexure, affirming its suitability for pavement quality concrete (PQC). Through this study, the phenomenon of efflorescence could also be explored, which was particularly significant during the winter seasons. Furthermore, the declining coefficient of determination (R2) with the rise in RAP, observed in the correlation between compressive strength and ultrasonic pulse velocity (USPV), likely signified increased variability in the mixture at higher replacement levels. Assessment of long-term performance in terms of resistance to surface abrasion established the mix as durable, depicting minimal depth of wear (0.081 mm). Furthermore, results of the rapid chloride penetration test (RCPT) demonstrated that the presence of adhered asphalt in RAP aggregates reduces porosity and enhances resistance. Microstructural study was additionally conducted to comprehend the importance of adhered asphalt in impeding crack propagation. ANOVA established a highly significant relationship between the interaction of curing age and RAP fractions with the strength characteristics of the mix. [ABSTRACT FROM AUTHOR]

Warm mix asphalt mixtures became attractive paving mixes by reducing the production temperature to around 25–40 °C as compared to that of conventional hot mix asphalt (HMA). This study aims to evaluate the warm mix asphalt (WMA) using wax-based additives by incorporating two types of industrial wastes. The potential application of low calcium fly ash (FA), i.e. class F type and marble dust (MD), has been evaluated by varying different percentage. The cylindrical samples were prepared and assessed for moisture susceptibility by being subjected to Marshall stability, retained Marshall stability (RMS), indirect tensile strength (ITS) and tensile strength ratio (TSR) tests. Furthermore, the samples were also evaluated for finding the refusal density, Cantabro loss and the rutting performance. A scanning electron microscope (SEM) was also used to evaluate the size and microstructure of the filler particles. The results revealed that the inclusion of fillers into mixes had significant improvement in the mechanical properties and lowered the rutting value with FA and MD addition. The warm mix additive and fillers used were also useful in reducing the binder content of the mixes. The mixing temperature was found to be in the range of 120–130 °C using the warm mix additive. The optimum usage of FA and MD can be up to 5% based on the evaluation. The statistical results reported that there was a significant difference between FA-based and MD-based WMA. [ABSTRACT FROM AUTHOR]

Engineered geopolymer composites (EGC) have emerged as a more environmentally friendly alternative to conventional engineered cementitious composites (ECC). These composites offer high mechanical and durability features. However, there is a lack of research on EGC, particularly with basic oxygen furnace (BOF) slag as a precursor and iron ore tailings (IOT) as a partial replacement to fine aggregate. Despite their effectiveness as industrial waste products in conventional concrete, this study aimed to determine the optimal compositions of fly ash (FA), steel fibres (SF), and IOT by varying their percentages. Overall, 150 mix combinations were tested, including six binder combinations, five combinations of fine aggregates, and five percentage variations in SF. Finally, one optimum mix was selected for each binder combination, based on the ultimate compressive strength values corresponding to the six optimal mixes. The compressive strengths of all the mixes were evaluated at both 7 and 28 days of curing, involving three replicate samples after oven curing (initial 24 h) followed by subsequent ambient curing until their respective ages. The highest observed compressive strength after 28 days was 41.77 MPa for 50 mm cubes. This strength was achieved with a composition of 60% FA, 1.5% SF, and 45% IOT. An increase in IOT percentage led to a nearly linear increase in strength, while the strength peaked at 1.5% for steel fibres. The addition of BOF slag significantly enhanced the compressive strength compared to mixes with full FA. A 40% fly ash replacement with BOF slag resulted in an average strength that was 39% higher than the combination with 100% fly ash. However, the strength growth decreased after a 10% replacement. Analysis of variance was conducted using the design of experiments methodology to determine the significance of the parameters and their interactions. All three independent parameters were found to be statistically significant, while their interactions were not. Utilizing Taguchi's analysis method with the L25 orthogonal array, it was concluded that IOT percentage was the most influential parameter. [ABSTRACT FROM AUTHOR]

Recent advances in the field of composite materials, aligning them with cost-effectiveness and environmental sustainability, have made the development of materials from industrial waste an attractive area of research. This work introduces an innovative approach for the reuse of globally available industrial waste by hybridizing organic and inorganic by-products to create low-cost composite materials with synergistically enhanced performances. Herein, industrial wastes, namely powdered wood chips (PWC) from the woodworking industry and fly ash (FA) derived from bagasse burning, were incorporated in a thermoplastic polypropylene (PP). Hybrid PP/PWC/FA composites at 70/20/10, 70/15/15 and 70/10/20 wt% were manufactured via extrusion process, followed by injection molding. Micrographic observations and infrared spectroscopy reveal that PWC particles have good physical adherence with PP. In contrast, the hydrophilic nature of FA leads to the creation of gaps at the interface due to the poor interfacial adhesion. The latter difference is reflected in the combined void nucleation modes of particle–fracture and particles–matrix interface decohesion during hybrid composites' tensile deformation. This provides a good synergistic stiffening effect for 70/20/10 wt% PP/PWC/FA hybrid composite, which offers the highest Young's modulus improvement of about 44.43%, while benefiting from balanced tensile strength and strain at yield. Furthermore, a two-way ANOVA at a significance level of 5% also proved the significant effect of PWC and FA reinforcement on the tensile parameters, as the p-values were below 0.05. Melt rheological properties demonstrate complex viscosity decrement for hybrid composites, suggesting a reduction in the energy required during production. Overall, the novel, high-performance hybrid composites developed can be manufactured with less energy consumption and are suitable for applications requiring high-temperature resistance and stiffness such as automotive, construction, and beyond. [ABSTRACT FROM AUTHOR]

Geopolymer is an environment friendly construction material that could be synthesized using either the natural source or the industrial byproducts such as flyash and GGBS. The characteristics of the Geopolymer rely on the proportion of the flyash and GGBS and the concentration of the activator solution used. In this research work, the effect of partial replacement of flyash with GGBS in proportions such as 0, 10, 20, 30 and 40% is investigated. Also Molarity of NaOH are tested from 8 to 14 M and both the parameters are optimized. In this optimized Geopolymer concrete, the utilization of iron slag as a partial substitute for river sand in various proportions such as 10, 15, 20, 25, 30 35, 40 and 45% are investigated. The optimized Geopolymer concrete with iron slag is investigated for its performance as a paver block with incorporation of banana fiber in proportions such as 0, 0.5, 1 and 1.5 and is compared with conventional cement concrete paver block. The results show that there is a significant enhancement in the properties of Geopolymer concrete with the different levels of optimization and the utilization of natural banana fiber. The developed sustainable paver block was found to with stand medium traffic conditions as per IS 15658:2006. Further this study employed random forest (RF) algorithm for the prediction of compressive strength of geopolymer concrete specimens for the variable parameters such as molarity of alkaline solution, Flyash/GGBS ratio and partial replacement of river sand with iron slag. The performance evaluation parameters represented high accuracy of developed RF model. This research work unleashes a heft potential of Geopolymer concrete to develop economical eco-friendly sustainable paver blocks to the society through mitigation of environmental strain on the ecosystem. [ABSTRACT FROM AUTHOR]

Geopolymer is an environment friendly construction material that could be synthesized using either the natural source or the industrial byproducts such as flyash and GGBS. The characteristics of the Geopolymer rely on the proportion of the flyash and GGBS and the concentration of the activator solution used. In this research work, the effect of partial replacement of flyash with GGBS in proportions such as 0, 10, 20, 30 and 40% is investigated. Also Molarity of NaOH are tested from 8 to 14 M and both the parameters are optimized. In this optimized Geopolymer concrete, the utilization of iron slag as a partial substitute for river sand in various proportions such as 10, 15, 20, 25, 30 35, 40 and 45% are investigated. The optimized Geopolymer concrete with iron slag is investigated for its performance as a paver block with incorporation of banana fiber in proportions such as 0, 0.5, 1 and 1.5 and is compared with conventional cement concrete paver block. The results show that there is a significant enhancement in the properties of Geopolymer concrete with the different levels of optimization and the utilization of natural banana fiber. The developed sustainable paver block was found to with stand medium traffic conditions as per IS 15658:2006. Further this study employed random forest (RF) algorithm for the prediction of compressive strength of geopolymer concrete specimens for the variable parameters such as molarity of alkaline solution, Flyash/GGBS ratio and partial replacement of river sand with iron slag. The performance evaluation parameters represented high accuracy of developed RF model. This research work unleashes a heft potential of Geopolymer concrete to develop economical eco-friendly sustainable paver blocks to the society through mitigation of environmental strain on the ecosystem. [ABSTRACT FROM AUTHOR]

Advanced and eco-friendly construction materials are being developed to reduce pollution and improve wastewater treatment efficiency. One such material is a photocatalytic nanocomposite that uses industrial wastes and natural substances to eliminate pollution. A recent study explored using an inorganic polymer composite (FM) made from a mixture of 70% fly ash and 30% metakaolin, with sodium hydroxide and sodium silicate as an alkali activator. The study evaluated the mechanical and hydration characteristics of the FM composite after 28 days in 100% humidity at room temperature. The study also examined the effect of adding 2.5 wt.% of Nano-TiO2 to FM composite and how it affects its properties. Results indicate that adding Nano-TiO2 to FM composite enhances its mechanical, antibacterial, and photocatalytic capabilities. Specifically, FM-TiO2 composite showed 90% removal of reactive blue 19 dye effluent in sunlight after 90 min, making it an excellent choice for sustainable wastewater treatment. This study presents a cost-effective, eco-friendly solution to wastewater treatment, with added antimicrobial properties from Nano-TiO2. [ABSTRACT FROM AUTHOR]

Geopolymer is an environment friendly construction material that could be synthesized using either the natural source or the industrial byproducts such as flyash and GGBS. The characteristics of the Geopolymer rely on the proportion of the flyash and GGBS and the concentration of the activator solution used. In this research work, the effect of partial replacement of flyash with GGBS in proportions such as 0, 10, 20, 30 and 40% is investigated. Also Molarity of NaOH are tested from 8 to 14 M and both the parameters are optimized. In this optimized Geopolymer concrete, the utilization of iron slag as a partial substitute for river sand in various proportions such as 10, 15, 20, 25, 30 35, 40 and 45% are investigated. The optimized Geopolymer concrete with iron slag is investigated for its performance as a paver block with incorporation of banana fiber in proportions such as 0, 0.5, 1 and 1.5 and is compared with conventional cement concrete paver block. The results show that there is a significant enhancement in the properties of Geopolymer concrete with the different levels of optimization and the utilization of natural banana fiber. The developed sustainable paver block was found to with stand medium traffic conditions as per IS 15658:2006. Further this study employed random forest (RF) algorithm for the prediction of compressive strength of geopolymer concrete specimens for the variable parameters such as molarity of alkaline solution, Flyash/GGBS ratio and partial replacement of river sand with iron slag. The performance evaluation parameters represented high accuracy of developed RF model. This research work unleashes a heft potential of Geopolymer concrete to develop economical eco-friendly sustainable paver blocks to the society through mitigation of environmental strain on the ecosystem. [ABSTRACT FROM AUTHOR]

A new type of inorganic fiber-fly ash continuous fiber was innovatively developed in this study to alleviate the problems of low comprehensive utilization rate and lacking of high-value utilization means of industrial solid waste fly ash. The melt flow temperature and macro-mechanical properties of different samples were studied. The results showed that with the increase in acidity coefficient index (MK), the melt flow temperature decreased first and then increased, and the lowest value was 1340 °C when MK was 3.1. Meanwhile, with the gradual increase in MK, the tensile strength and elastic modulus of monofilament increased first and then decreased. When the MK was 3.8, the tensile strength and elastic modulus of fiber monofilament reached 2064 MPa and 16.7 GPa, respectively. According to the results of XRD, TG-DSC, FTIR and SEM microstructure analysis methods, it is found that the macro-mechanical properties of fibers are closely related to the chemical composition and phase structure evolution of raw materials. After melting at high temperature, the samples with high MK form a dense three-dimensional glassy network structure, which leads to the higher mechanical strength of the fibers. However, in the samples with lower MK, the vitreous network structure is loose, which reduces the mechanical properties of the fiber. Finally, the MK range (2.5–3.8) for preparing high-performance fly ash fiber was proposed in this paper. In this range, the synthesized fly ash continuous fiber has low melting temperature and excellent mechanical properties, which has a potential of industrial application. [ABSTRACT FROM AUTHOR]

The discharging of lead-contaminated wastewater is a concern because of its toxicity to living organisms and water quality resulting in dangerous water consumption, so it is highly recommended to remove lead from wastewater to be below water quality standards for a safe environment. Zeolite A sugarcane bagasse fly ash powder (ZB), zeolite A sugarcane bagasse fly ash powder mixed iron(III) oxide-hydroxide (ZBF), zeolite A sugarcane bagasse fly ash beads (ZBB), zeolite A sugarcane bagasse fly ash powder mixed iron(III) oxide-hydroxide beads (ZBFB), and zeolite A sugarcane bagasse fly ash beads coated iron(III) oxide-hydroxide (ZBBF) were synthesized and characterized in various techniques. Their lead removal efficiencies were investigated by batch experiments, adsorption isotherms, and kinetics. The specific surface area, pore volume, and pore size of ZB were close values to zeolite A standard (STD), and ZBF had the highest specific surface area and the smallest pore size than others. ZB and ZBF demonstrated crystalline phases whereas ZBB, ZBFB, and ZBBF were amorphous phases. The surface morphology of ZB was a cubic shape similar to STD. ZBF demonstrated an agglomerated formation of ZB and iron(III) oxide-hydroxide whereas ZBFB and ZBBF had sphere shapes with coarse surfaces. Si, Al, O, Fe, Na, Ca, O–H, (Si, Al)–O, H2O, and D4R were detected in all materials. The surface charges of all zeolite A materials had negatively charged at all pH values, and their surfaces increased more negatively charged with increasing pH value which pH 5 illustrated as the highest negatively charged in all materials. Their lead removal efficiencies were higher than 82%. Langmuir isotherm and pseudo-second-order kinetic models were well explained for their adsorption patterns and mechanisms. Finally, ZBBF is a good offer for applying in industrial wastewater treatment systems because of its easy operation and saving costs than ZBF. [ABSTRACT FROM AUTHOR]

The discharging of lead-contaminated wastewater is a concern because of its toxicity to living organisms and water quality resulting in dangerous water consumption, so it is highly recommended to remove lead from wastewater to be below water quality standards for a safe environment. Zeolite A sugarcane bagasse fly ash powder (ZB), zeolite A sugarcane bagasse fly ash powder mixed iron(III) oxide-hydroxide (ZBF), zeolite A sugarcane bagasse fly ash beads (ZBB), zeolite A sugarcane bagasse fly ash powder mixed iron(III) oxide-hydroxide beads (ZBFB), and zeolite A sugarcane bagasse fly ash beads coated iron(III) oxide-hydroxide (ZBBF) were synthesized and characterized in various techniques. Their lead removal efficiencies were investigated by batch experiments, adsorption isotherms, and kinetics. The specific surface area, pore volume, and pore size of ZB were close values to zeolite A standard (STD), and ZBF had the highest specific surface area and the smallest pore size than others. ZB and ZBF demonstrated crystalline phases whereas ZBB, ZBFB, and ZBBF were amorphous phases. The surface morphology of ZB was a cubic shape similar to STD. ZBF demonstrated an agglomerated formation of ZB and iron(III) oxide-hydroxide whereas ZBFB and ZBBF had sphere shapes with coarse surfaces. Si, Al, O, Fe, Na, Ca, O–H, (Si, Al)–O, H2O, and D4R were detected in all materials. The surface charges of all zeolite A materials had negatively charged at all pH values, and their surfaces increased more negatively charged with increasing pH value which pH 5 illustrated as the highest negatively charged in all materials. Their lead removal efficiencies were higher than 82%. Langmuir isotherm and pseudo-second-order kinetic models were well explained for their adsorption patterns and mechanisms. Finally, ZBBF is a good offer for applying in industrial wastewater treatment systems because of its easy operation and saving costs than ZBF. [ABSTRACT FROM AUTHOR]

Gold mine tailings, fly ash, and bagasse ash has been repurposed to produce geopolymer (GP) with enhanced electromagnetic interference shielding efficiency (EMI-SE) and high thermal property. GP has low shielding efficiency compared to concrete. Due to this, an appropriate filler must be incorporated into its matrix to enhance its EMI-SE. For this study, bismuth oxide nanomaterial (BiNP) was utilized as the additive filler. The percent content of BiNP was varied to evaluate its influence on the EMI-SE of GP. Morphology shows that Bi2O3 was embedded in the matrix of GP, and no new aluminu-phyllosilicate minerals were formed. This indicates that some minerals acted only as internal fillers in the matrix. Compressive strength shows synthesized GP composites were more than 20 MPa, with neat GP reaching the maximum strength. Moreover, the EMI-SE of neat GP was 21.2 dB for 20–4500 MHz range. This indicates that GP alone has sufficient characteristics to attenuate EMI radiation. Addition of 5%, 10% and 15% weight of BiNP improves EMI-SE by 4–10%, with 5% BiNP shown to be the optimum ratio. Lastly, the addition of BiNP improves the thermal stability of GP. This study shows that GP incorporated with Bi2O3 can be recommended for small-scale construction and small residential building. [ABSTRACT FROM AUTHOR]

To reduce the filling cost of high-water backfilling material (HWBM) in mining backfill and improve the recycling utilization of the industrial waste such as the coal fly ash. The ultra-fine fly ash (UFA) was added to the HWBM as a partial replacement in this work. Therefore, a series of experiments were performed to investigate the effect of UFA on the mechanical properties of the HWBM at the different curing conditions, then the hydration mechanism of the HWBM blended with UFA was analyzed by XRD and SEM method. The result indicates that the strength of the HWBM decreased with the increasing of UFA dosages, but the addition of UFA can improve the residual strength of the initial HWBM. Additionally, when the HWBM was cured at the laboratory air condition, its carbonation process was restrained obviously as the UFA dosages were less than 15% at the ages of 28 days, which indicates the UFA can improve the weathering resistance of the HWBM with the curing ages increasing effectively. The XRD and SEM results also shows that the degree of crystallinity of the HWBM increased when UFA dosages were less than 15% effectively, while there were few obvious changes on types of hydration products. It indicates that the main affects of UFA on the performance of HWBM is filler and dilution, which reduced the contact area between hydration products of HWBM and CO2 in the air, further improved the carbonation resistance of HWBM. [ABSTRACT FROM AUTHOR]

A new adsorbent with chromium removal function was synthesized by carbon thermal method using iron-containing waste Fenton sludge and carbon-containing solid waste fly ash to treat high pH scoring wastewater generated from industrial processes. The results showed that the adsorbent used T = 273.15 K, pH = 10, t = 1200 min, C0 = 100 mg/L, had a removal rate of Cr(VI) of more than 80%, and the adsorption capacity could reach 393.79 mg/g. The characterization results show that the synthesized mesoporous nitrogen-doped composite material has a large specific surface area and mesoporous structure, and the surface of the material is rich in oxygen-containing functional groups and active sites. Compared with other studies, the adsorption capacity of the material is larger, which indicates that the removal effect of Cr(VI) in this study is better. The adsorption kinetic results show that the adsorption follows a pseudo second kinetic model, and the adsorption process is a chemisorption involving electron sharing or electron exchange. This experiment designed a simple method to synthesize mesoporous nitrogen-doped composites using industrial solid waste, with raw materials from cheap and easily available industrial solid waste, and solved the dual problems of heavy metals in wastewater and solid waste, providing a new idea for the resource utilization of Fenton sludge while not producing secondary pollution. [ABSTRACT FROM AUTHOR]

The cost, flux and rejection rate of the membrane are the main factors in the process of water reclamation and reuse. A new type of composite membrane can be prepared by using fly ash (FA) and polyurethane (PU). The structure and properties of composite membrane can be adjusted by the theory of pigment volume concentration (PVC) to treat wastewater containing methylene blue (MB). The morphology, FT-IR spectroscopy, wettability, diffusivity, flux and rejection rate of the composite membrane were studied. The results showed that when PVC was close to the critical pigment volume concentration (CPVC), the performances of the 3# (PVC = 40.03%) composite membrane, the mass ratio of FA to PU was 1.44: 1, were the best. The flux and rejection rate for MB solution of the 3# membrane were 66.52 L·m−2·h−1 and 96.77%, respectively. At the same time, there was no serious pollution on the membrane with a long-term application. In addition, several typical organic wastewaters were treated by this composite membrane. The rejection rates for organic pollutants such as Rhodamine B, phenol and actual industrial wastewater were 96.12%, 96.48%, and 97.58%, respectively. The sustainable technology for the recovery and reuse of water by using solid waste in wastewater treatment has good environmental and social benefits. [ABSTRACT FROM AUTHOR]

The primary goal of this research is to determine the mechanical properties of opaque glazed ceramic tiles containing fly ash, tincal waste, and recycled red clay, including to assess if the results meet international requirements. Opaque glaze and tincal waste were the main components of all glaze compositions of four groups, which were named OG (original), FA, RC, and FC (mixture) according to the additive. The ceramic tiles were prepared by dipping the biscuits in the glaze composition and firing them at 1150°C. The water absorption of the FA, RC, and FC tiles was less than that of the OG tiles (< 0.52%) and the scratch hardness values were between 6 and 7. All the experimental groups were also resistant to thermal shock, chemicals, and staining showing high opacity (L* > 92) and having a light yellow–red color. The micro- and crystallographic structure of some selected tiles were determined by scanning electron microscopy and x-ray diffraction techniques. Zircon, diopside and augite phases were recognized. [ABSTRACT FROM AUTHOR]

One-part alkali-activated materials (AAMs) are developed to improve conventional two-part systems. One-part AAMs technology has been used in cement binders to produce concrete, mortar, and paste. Current research mainly focuses on synthesizing raw materials obtained from industrial and agricultural waste as the main aluminosilicate precursors of the cement binder for a concrete application. The one-part AAMs were reported to have higher early compressive strength at 7 days of age, contributed by its fast-setting time, mainly when the binder activates by a higher dosage of alkaline activator and containing OPC-rich. Due to bonding issues, single or combination, FA/GGBFS/MK precursors were reported as unsuitable for use as a concrete repair material. They were the reason for the lack of one-part AAMs application of mortar compared to concrete usage. This study was conducted to determine the potential of one-part AAMs used as concrete patch mortar by investigating its rheology and mechanical properties. The compressive strength of the mortar was tested under lab ambient temperature in the tropical climate country of Malaysia. The setting time of fresh mortar and bonding strength were set under controlled lab temperature. The one-part alkali-activated mortar was composed of hybrid aluminosilicate precursors between fly ash (FA), Ground Granulated Blast Furnace Slag (GGBFS) and ordinary Portland cement (OPC). A low alkaline activator of solid potassium carbonate was used for the geopolymerization process. Three types of solid admixtures were added to complete the composition of the new mix design. The experiment's outcome showed that the mortar composed with the combination of conventional Portland cement and industrial waste products has compressive and pull-off adherence strength that meets with Class R3—EN1504-3 standard for structural concrete repair materials requirement. [ABSTRACT FROM AUTHOR]

Present invention was indented for characterization and adsorptive (batch and column) treatment of sugar industry distillery spent wash to remove COD (chemical oxygen demand) and color using sugarcane industrial waste, bagasse fly ash (BFA). Distillery spent wash was extremely polluted including acidic pH and very high value of COD, BOD (biological oxygen demand) and color. Sophisticated techniques such as BET (Brunauer–Emmett–Teller) surface area, pore volume, pore diameter, particle size distribution, porosity, FTIR (Fourier-transform infrared spectroscopy), chemical composition by XRF (X-ray fluorescence) and SEM (scanning electron microscopy) were utilized to analyze BFA as an adsorbent and revealed that BFA surface was highly porous and consisted of various oxides. In batch treatment, different process parameters such as contact duration and temperature w.r.t adsorbent dose, thermodynamic studies and isotherms (Langmuir and Freundlich model) were analyzed. Column adsorption was performed using various variables (bed height, particle size distribution and flow rate), breakthrough parameters and isotherms (Thomas, Yoon–Nelson, BDST and Adams and Bohart model). Adsorption capacities were increased with increasing BFA dose, contact duration, temperature, bed height and decreasing flow rate and average particle size. The maximum adsorption capacity of Langmuir and Thomas model was achieved up to 124.5 mg g−1 and 0.1394 mg g−1, respectively, for COD and 109.8 (Hazen L) gm−1 and 0.2547 (Hazen L) gm−1, respectively, for color. Sugar Industry wastewater stream, i.e., distillery spent wash was shown to be feasible using own industrial solid waste, BFA. [ABSTRACT FROM AUTHOR]

The Congo Red dye was removed from a simulated textile wastewater solution using fly ash from a local power plant. The characterisation of fly ash was studied in detail by SEM, EDX, XRD, FTIR, BET surface area and TGA techniques. The influence of four parameters (contact time, initial concentration, adsorbent dose, and temperature) was analysed, the results showing that the adsorption capacity depends on these parameters. Thermodynamic and regeneration investigations as well are presented. The fit to pseudo-second-order kinetics models suggests that the removal process is a chemical adsorption. The Langmuir model fitted the experimental data, with a maximum adsorption capacity of 22.12 mg/g. The research is a preliminary case study that highlights that fly ash posed a very good potential as a material for Congo Red dye removal. [ABSTRACT FROM AUTHOR]

Zeolites are porous aluminosilicate materials and are commonly used as adsorbents for various pollutants. Geopolymers made from industrial waste materials have an aluminosilicate structure similar to zeolites and can be converted to crystalline zeolites under high temperature and pressure conditions (hydrothermal conditions). The present study investigated the effects of fly ash substitution by calcium aluminate cement (CAC) in hydrothermally-treated geopolymer binders (often referred to as geopolymer-zeolite composites or geopolymer-supported zeolites). The substitution levels of fly ash by CAC were varied from 0 to 50% (0, 10%, 20%, 40%, or 50%). A mixture of waterglass and NaOH solutions was used for alkali activation of raw materials. The test results revealed that the CAC significantly affected the strength development and reaction products. All the CAC-substituted specimens showed significantly higher strength than fly ash-based control specimens. It was noted that the rise in compressive strength was mainly due to the formation of C–A–S–H gel in CAC-substituted specimens. The control specimens showed Na–P1 type zeolite while chabazite, faujasite, and hydroxysodalite phases were identified with incorporation of CAC. Hence, it was found that the CAC addition resulted in different Ca/Si molar ratios, which promoted the formation of different types of zeolites, thus these specimens can potentially be used for specific target applications. [ABSTRACT FROM AUTHOR]

Heavy metals are perceived as a significant environmental concern because of their toxic effect, bioaccumulation, and persistence. In this work, a novel sodium alginate (SA) and carboxymethylcellulose (CMC) entrapped with fly ash derived zeolite stabilized nano zero-valent iron and nickel (ZFN) (SA/CMC-ZFN), followed by crosslinking with CaCl2, is synthesized and applied for remediation of Cu(II) and Cr(VI) from industrial effluent. The characterization of the adsorbent and its surface mechanism for removing metals were investigated using advanced instrumental techniques, including XRD, FT-IR, SEM–EDX, BET, and XPS. The outcomes from the batch experiments indicated that monolayer adsorption on homogeneous surfaces (Langmuir isotherm model) was the rate-limiting step in both heavy metals sorption processes. The maximum adsorption capacity of as-prepared SA/CMC-ZFN was 63.29 and 10.15 mg/g for Cu(II) and Cr(VI), respectively. Owing to the fact that the wastewater released from industries are large and continuous, a continuous column is installed for simultaneous removal of heavy metal ions from real industrial wastewater. The outcomes revealed the potential of SA/CMC-ZFN as an efficient adsorbent. The experimental breakthrough curves fitted well with the theoretical values of Thomas and Yoon-Nelson models. Overall, the results indicated that SA/CMC-ZFN is a viable, efficient, and cost-effective water treatment both interms of batch and column processes. [ABSTRACT FROM AUTHOR]

Owing to the increased population in developing country like India, the demand of sustainable building material is likewise increased to meet its excessive consumption. In the present study, non-autoclaved aerated geopolymer (NAAG) blocks were developed using industrial waste [fly ash, granulated blast furnace slag (GGBS)], foam and aerating agents with less concentration of alkaline solution (i.e. 1.5–4 M) and tested for their physio-mechanical properties. These NAAG blocks achieved up to 13.5 MPa compressive strength. Optimized samples were tested for thermal and durability related properties. Performance evaluation of NAAG blocks exhibited low thermal conductivity and durable nature as compared to the clay bricks. This developed NAAG block is proven to be a cost-effective and energy effective solution and can be used as building material. [ABSTRACT FROM AUTHOR]

The existing high market potential for supercapacitors in electric vehicles created enthusiasm for the development of safer and high-performance supercapacitor gadgets. The ongoing examination endeavors on electrochemical power sources are composed toward achieving high-explicit energy, high-explicit power, long-cycle life, and so forth, at a realistic cost. In this work, low-cost hybrid material of polyaniline-sulfate salt and ash from the bituminous coal is synthesized via in situ polymerization of aniline. The formation of hybrid in this polymerization process was confirmed from FTIR, XRD, EDAX, and TGA. Thus, prepared polyaniline-sulfate●ash (PANI-ash) hybrid is taken as electro-active material for the construction of supercapacitor cell in a symmetric configuration in 1 M H2SO4 electrolyte. PANI-ash, wherein ash prepared at 600 oC of bituminous coal, gave higher electrochemical performance compared to its individual components of PANI and ash materials. Initial specific capacitance observed for the samples of PANI, PANI-A400, and PANI-A600 are 155, 328, and 363 F g−1, respectively. PANI-A600 symmetric cell system subjected to a higher current density of 0.75 A g−1 for 10,000 cycles. Remaining in specific capacitance values of polyaniline salts at 10,000 CD cycles is found to be 70 %, and further at 35,000 cycles, it shows 43% retention of specific capacitance. [ABSTRACT FROM AUTHOR]

In the present study, two potential industrial waste materials, such as, fly ash (FA) and lime sludge (LS) that are generated in bulk quantities and poses environmental hazards were mixed and stabilized using lime (CL) and gypsum (G) in order to make them suitable for use in Civil Engineering construction applications. Different mix proportion of FA and LS stabilized with different % of CL and G were studied and tested for unconfined compressive strength (UCS), split tensile strength test (STS) and California bearing ratio (CBR) to check the suitability of prepared composite for construction industries. It is noted that the optimal composition consisted of FA and LS in 1:1 ratio, 12% CL and 1% G content. The composite was also found to be durable with no leaching of heavy metals. Further, the selected composite was further studied for the microstructural development through scanning electron microscopy (SEM) and X-ray diffraction (XRD) to understand the phenomenon of chemical process or reaction and reason for strength gain. The developed composite (50FA + 50LS + 12CL + 1G) is suggested for application as base course layer material in flexible pavements due to its good requisite strength and durability. It is further highlighted that issues of uncertainty in strength and stiffness characteristics of pavement layer materials and its implications on analysis and design of flexible pavements can be studied through reliability based approach in combination with numerical analysis and Monte Carlo simulations. [ABSTRACT FROM AUTHOR]