Cement Kiln Research Articles

Experimental Investigation of Recycling Cement Kiln Dust (CKD) as a Co-Binder Material in Cemented Paste Backfill (CPB) Made with Copper Tailings

Experimental Investigation of Recycling Cement Kiln Dust (CKD) as a Co-Binder Material in Cemented Paste Backfill (CPB) Made with Copper Tailings

Integration of Waste Management in Textile Industries of India

The foundation of India's economic growth, the textile sector, has experienced unheard-of growth in recent decades, along with a rise in environmental issues brought on by significant waste generation. This comprehensive study sets out to look into and analyze how waste management techniques are incorporated into the rich history of the Indian textile sector. The study offers a thorough review of current waste management techniques, environmental impact evaluations, and creative solutions influencing the path toward sustainability, bridging the gap between qualitative and quantitative analysis. The introduction sets the context by outlining the mutually beneficial relationship between the expansion of the textile industry and its subsequent environmental load. The clothing industry has gained prominence due to the increase in demand for its products, however, a paradigm shift is required due to the waste generated by this industry. The study aims to perform a thorough analysis of waste management processes, conduct a quantitative assessment of the environmental implications, and investigate comprehensive strategies for sustainable waste management. The chapter on qualitative analysis explores the complex aspects of waste management in the textile industries of India. This section explains the nuances of waste generation at different phases of textile production by carefully examining existing methods, case studies, and industry dynamics. A thorough grasp of the qualitative landscape is revealed, encompassing everything from yarn and fabric waste to the difficulties presented by chemical residues and the disposal of end-of-life textiles. The importance of awareness and corporate responsibility in influencing waste management methods is also highlighted in this section. Case studies of top textile producers present creative approaches and offer insights into the possibilities of technological developments, cooperative efforts, and models of the circular economy. Nonetheless, difficulties ranging from technology constraints to cultural obstacles highlight how difficult it is to smoothly integrate sustainable practices throughout the sector. The chapter on integration strategies looks at potential directions that could change the way waste is managed in the textile industry in India. Models of the circular economy take center stage because they provide a comprehensive approach to production and disposal. Case studies from real-world applications highlight the revolutionary potential of upcycling and sophisticated recycling technology, offering insights into how these strategies could lessen the industry's environmental impact. Co-processing in cement kilns is a two-pronged method that solves waste disposal issues and produces useful resources. The potential for improved trash sorting and identification is demonstrated by the combination of artificial intelligence and data analytics, opening the door to increased process efficiency in waste management. The study's conclusion emphasizes that although the study has been helpful, the search for India's sustainable textile waste management is still an ongoing project. The industry is at a turning point in its evolution, and the factors pushing it in that direction will be sustained research and innovation leading the way toward a time when environmental stewardship and economic prosperity coexist together. Every thread woven into the fabric of the Indian textile industry offers a story of sustainability, adaptability, and responsible International Journal of Scientific Research in Engineering and Management (IJSREM) Volume: 08 Issue: 07 | July - 2024 SJIF Rating: 8.448 ISSN: 2582-3930 © 2024, IJSREM | www.ijsrem.com DOI: 10.55041/IJSREM36458 | Page 2 growth; therefore, the success of this journey will depend on the collective duty of industry stakeholders, policymakers, and consumers. Essentially, the goal of this extensive study is to serve as a compass for the Indian textile sector, offering a path forward to a time when environmental conservation and economic growth coexist peacefully.

Mechanical performance of eco-friendly self-compacting concrete (SCC) mixtures and two-way slabs partially containing cement kiln dust as cement replacement and internally reinforced with waste plastic mesh

A large quantity of cement kiln dust (CKD) is produced annually during the production of Portland cement. The majority of the produced CKD remains unused except in specific cases related to soil stabilization projects. The current research investigates the production of self-compacting concrete (SCC) mixtures, in which CKD is used as a substitute for cement in different weight proportions, 3 %, 6 %, 9 %, 12 %, and 15 %. The hardened mechanical properties of SCC, such as compressive strength, splitting tensile strength, and flexural strength, as well as the fresh state characteristics (i.e., slump flow diameter, T500, V-funnel, and L-box tests), were recorded and compared with the control mixture which was entirely cast using cement. Results revealed that with an increase in the CKD content beyond 6 %, the slump flow diameter of SCC mixtures significantly decreased. Also, the increase ratios in the V-Funnel flow time for self-compacting concrete mixtures, when replacing cement with CKD ratios of 3 %, 6 %, 9 %, 12 %, and 15 %, were 13.3 %, 30 %, 46 %, 58 %, and 66.7 % respectively, compared with the reference mixture. Additionally, the impact behavior of two-way SCC slabs cast using CKD ratios ranging from 3 to 15 % and internally strengthened using various patterns of recycled plastic mesh was investigated. Strengthening the SCC slabs using two layers of recycled plastic grids proved to be effective in preventing the projectile from penetrating the whole thickness of the SCC slabs, regardless of the CKD content.

Utilization of accelerated weathering of limestone captured carbon dioxide (CO2) with cement kiln dust to produce building material

The accelerated weathering of limestone (AWL) process is an inexpensive and eco-friendly carbon dioxide (CO2) capture process with comparable performance to amine-based systems. However, the generated calcium bicarbonate (Ca(HCO3)2) solution lacks an effective utilization alternative. Aside from that, the current solid waste utilization alternatives (i.e., carbon mineralization and partial replacement of conventional binders) lack the capability to effectively curb the tremendous production rate of solid waste (i.e., cement kiln dust (CKD)). To address both gaps, this study developed a novel Ca(HCO3)2 solution utilization alternative with CKD as the sole binder to produce a building material termed CKD-bicarbonate lime mortar (BLM). This work aims to identify the optimal mix ratio for CKD-BLM to achieve maximum compressive strength via a series of studies; (i) liquid medium, (ii) Ca(HCO3)2 solution volume, and (iii) sand:CKD mix ratio. From the findings, it was found that CKD-BLM at the optimal CKD:sand:Ca(HCO3)2 mix ratio of 1:0.45:0.29 exhibits the highest compressive strength of 2.09 MPa, surpassing the compressive strength standard of 1.70 MPa set by the ASTM C141 while having acceptable workability of 118 % which is within the standard workability range of 105–155 % set by ASTM C270. However, the CKD-BLM sample exhibits high leaching of Ca, Si, Na and Cl which does not meet the environmental regulation. This was resolved by applying a waterproof coating that effectively curbed the leaching by 28.84–99 %. Overall, this study successfully developed a building material with industrial wastes (i.e., Ca(HCO3)2 solution and CKD) that surpasses the performance of conventional lime mortar while utilizing up to 0.22 kg CO2.kg CKD-BLM_1:0.45:0.29−1.

Feasibility of Natural Fibre Usage for Wind Turbine Blade Components: A Structural and Environmental Assessment

There are two key areas of development across wind turbine blade lifecycles with the potential to reduce the impact of wind energy generation: (1) deploying lower-impact materials in blade structures and (2) developing low-impact blade recycling solution(s). This work evaluates the feasibility of using natural fibres to replace traditional glass and carbon fibres within state-of-the-art offshore blades. The structural design of blades was performed using Aeroelastic Turbine Optimisation Methods and lifecycle assessment was conducted to evaluate the environmental impact of designs. This enabled the matching of blade designs with preferred waste treatment strategies for the lowest impact across the blade lifecycle. Flax and hemp fibres were the most promising solutions; however, they should be restricted to use in stiffness-driven, bi-axial plies. It was found that flax, hemp, and basalt deployment could reduce Cradle-to-Gate Global Warming Potential (GWP) by around 6%, 7%, and 8%, respectively. Cement kiln co-processing and mechanical recycling strategies were found to significantly reduce Cradle-to-Grave GWP and should be the prioritised strategies for scrap blades. Irrespective of design, carbon fibre production was found to be the largest contributor to the blade GWP. Lower-impact alternatives to current carbon fibre production could therefore provide a significant reduction in wind energy impact and should be a priority for wind decarbonisation.

The effective treatment of dye-containing simulated wastewater by using the cement kiln dust as an industrial waste adsorbent

This study compares the adsorption behavior of both Methylene Blue (MB) and Congo Red (CR) dyes on the surfaces of cement kiln dust (CKD) powder from the experimentally simulated wastewater solution. The cement kiln dust powder was characterized using X-ray Fluorescence (XRF), X-ray diffraction (XRD), N2 adsorption–desorption Brunauer–Emmett–Teller (BET), Fourier Transform Infrared Spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) tests. The adsorption for such dyes was studied under varying mixing contact times, temperatures, and pH as well as various initial concentrations of both dyes and adsorbent using the batch mode experiments. Pseudo-first-order, pseudo-second-order, and intraparticle diffusion models were applied, and the results revealed that the pseudo-second-order fitted well to the kinetic data. Thermodynamic parameters stated that the adsorption process was endothermic. Studying Linear and nonlinear forms of Langmuir and Freundlich's adsorption isotherms revealed that the adsorption process was followed by both homogeneous mono-layer and heterogeneous multilayer coverage on the active sites of cement kiln dust particles. The data showed that the adsorption capacities of the methylene blue and Congo red dyes were 58.43 and 123.42 mg/g, respectively and cement kiln dust is an adsorbent with little cost for the treatment of wastewater.

Evaluating the Potential of Refuse Derived Fuel (RDF) in Cement Production: a Comparative Analysis of RDF Variations In Indonesia's Emplacement Pluit, Jakarta

This study critically evaluated the potential of Refuse Derived Fuel (RDF) as a sustainable substitute for coal in the cement manufacturing process. Using Emplacement Pluit's waste as a primary source, three distinct RDF variations were analyzed: RDF A (comprised purely of PET Charcoal), RDF B (a 50-50 combination of PET Charcoal and organic waste), and RDF C (solely organic waste). Among the parameters evaluated were moisture content, ash content, and calorific value. The results indicated RDF A's superior quality, with a moisture content of 2.6%, ash content of 0.7%, and a calorific value of 25.1 MJ/kg. In stark contrast, RDF C exhibited a high waste reduction potential at 80.5%, but its calorific value fell short of Korean standards. RDF B, balancing quality and reduction potential, achieved a 98.9% waste reduction and met Korean RDF standards, making it the most viable alternative to coal in cement production. The study underscores the significant potential of integrating RDF in industrial practices, particularly cement kilns. It offers insight into optimizing waste management strategies in line with the 'zero-waste' vision.

Innovative Multigeneration System with Heat Exchangers for Harnessing Thermal Energy from Cement Kiln Exhaust Gases

Innovative Multigeneration System with Heat Exchangers for Harnessing Thermal Energy from Cement Kiln Exhaust Gases

A comparative study of the mechanical and thermal properties of EPDM rubber/cement kiln dust composite cured by ionizing radiation

In this work, cement kiln dust (CKD) will be studied as an unconventional filler for ethylene-propylene-diene terpolymer (EPDM) rubber as an alternative to silica, which is widely used as filler for many types of rubber. (EPDM)/CKD rubber composites were fabricated using ionizing radiation. EPDM rubber was blended with different portions of cement-kiln dust 5, 10, 15, 20, 25, and 30 phr (phr = parts per hundred rubber). The prepared composites were cured by exposing to different doses of gamma rays up to 150 kGy to enhance the crosslinking of the EPDM rubber. The thermo-mechanical properties of the EPDM/CKD and EPDM/Si composites were investigated as a function of irradiation dose. The results showed a significant improvement in elongation and tensile strength by incorporating cement dust into EPDM rubber up to 20 phr, which is not significantly different from composites incorporated with silica. Gamma irradiation significantly improved the properties of all formulations.

Regional heterogeneity of sustainable wastewater sludge management in China

In various regions of China, the sludge characteristics, available sludge treatment and disposal routes, and economic and environmental concerns exhibit significant variations. This makes it challenging for regions to select appropriate technologies for sustainable sludge management. This study proposed a universal framework that integrates carbon emissions, economic cost, and environmental risk potential to assess sustainability of diverse sludge treatment and disposal routes in different regions of China. An up-to-date database of sludge characteristics in different regions of China has also been created. Depending on sludge characteristics, co-incineration in coal-fired plants or cement kilns and thermal hydrolysis-anaerobic digestion routes demonstrate outstanding sustainability for most regions in China. Moreover, the current carbon trading price in China is low and does not significantly influence the technical selection. The created sludge characteristics database and the sustainability assessment framework could help sludge managers make better in process selection, technological improvement, and future policy formulation.

Characterization and utilization capabilities of industrial wastes for green bricks production

BackgroundThe goal of this study is to develop a feasible and sustainable solution to manage the use of industrial wastes of ground granulated blast-furnace steel slag (GGBS) activated by cement kiln dust (CKD) and quicklime (QL). Using activated GGBS in the manufacture of stabilized green bricks is still uncommon in Egypt in such applications. Five clay-based mixtures, each with varying replacement ratios (5–10, wt.%) of CKD and QL, were studied. Laboratory tests were conducted on cylindrical specimens made from these mixtures, which were left to cure for periods of up to 60 days. The raw materials and lab-made specimens were analyzed using particle size analysis, differential thermal analysis, X-ray fluorescence, and X-ray diffraction techniques. The physical and mechanical properties of the cured specimens were also determined and evaluated according to standard specifications. Furthermore, the durability of the cured specimens was evaluated against collapsibility in water.ResuItsIt has been observed that adding QL and CKD to the stabilized green specimens of different mixes can enhance their engineering properties with curing age increasing. This is due to the pozzolanic reaction, which fills the pore structure with calcium silicate hydrates and calcium aluminate hydrates gel. The ratio of QL and CKD used significantly affected the engineering properties of the specimens. The study found that using 20% GGBS and 5% QL led to an increase in compressive strength (266 kg/cm2) at the density of (2.15 g/cm3), while also water absorption was reduced (8%) to give superior results. When GGBS and CKD were combined, a higher content of CKD (10 wt.%) gave better results compared to (5 wt.%) CKD. Furthermore, the physical and mechanical properties of the tested specimens (MD 1, MD II, MD III and MD IV) met the acceptable limits of dry compressive strength (30–70 kg/cm2), water absorption (8–15%), and density (1.7–2 gm/cm3), as specified by the Egyptian standard specifications for buildings used compressed earth blocks.ConclusionThe CKD and QL act as alkali activators for GGBS and can be utilized in masonry construction.

Formulation of high-recycled-content hydraulic cements based on alkali aluminosilicate chemistry and mechanochemical processing techniques

The current study investigates the potential of various waste materials and industrial by-products for formulating high-recycled content hydraulic cement, leveraging alkali aluminosilicate chemistry principles. Through rigorous characterization employing X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier Transform Infrared (FTIR) Spectroscopy, thermogravimetric analysis (TGA), and Scanning Electron Microscopy (SEM), alongside alkalinity and alkali solubility assessments, the chemical and mineralogical compositions of waste brick, lime kiln dust, cement kiln dust, waste glass, gypsum, foundry sand, granulated blast furnace slag, and impounded coal ash were unveiled. Silicon and aluminum were found abundantly in these materials, with lime kiln dust and slag contributing calcium. A thoroughly crafted blend, enriched with alkalis, underwent mechanochemical activation to yield a hydraulic cement finely tuned to meet specific chemical ratios required for effective alkali aluminosilicate reactions. Upon hydration, this innovative cement exhibited rapid early strength development, achieving a commendable compressive strength of 32 MPa within 28 days a performance on par with standard Portland cement. Remarkably, the heat of hydration profiles revealed a prompt onset of hydration reactions, marked by a significant exothermic peak within the initial hours, in contrast to the gradual peak observed with Portland cement. TGA/DTA results further corroborated the thermal stability of the hydration products formed. Alkali-solubility assessments of the raw materials emerged as reliable indicators of their reactivity within the cement matrix, with solubility values exceeding 20 % for waste glass and impounded coal ash, signifying their high potential for alkali activation. The culmination of this research underscores the feasibility of re-composing waste materials to craft alkali aluminosilicate cement, offering performance akin to conventional options. These findings advocate for the adoption of sustainable material utilization in construction, paving the way for enhanced industrial symbiosis in cement production.

Improving Soft Subgrade Stability Using a Novel Sustainable Activated Binder Derived from By-Products

Soft soil concerns, due to high compressibility and low bearing capacity, prompted an investigation into stabilizing clay soil. Traditionally, binder including cement or lime has been used as stabilizers though a current requirement of alternatives is stem from environmental concerns. The study focused on the viability of using a novel binary activated blended binder composed of environmentally friendly materials, namely ground granulated blast furnace slag (GGBS) activated by cement kiln dust (CKD). The experimental work included investigating the impact of the developed binders on the Atterberg limits, standard Proctor compaction, California Bearing Ratio (CBR), unconfined compressive strength (UCS), and field-emission scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy. CBR tests were conducted after 7 days of curing or soaking, while UCS and SEM analyses were conducted after 7 and 28 days of curing. A fixed binder ratio of 9% was maintained, with GGBS blended at 25%, 50%, and 75% with CKD. For comparison, samples of untreated and treated soils with unary binders from GGBS and CKD were also prepared. Results indicated that activated binders notably decreased soil plasticity and maximum dry density, while elevating optimum moisture content, CBR, and UCS, especially in later stages of treated soil and unary GGBS binder. Unary CKD binder exhibited a similar trend to activated binders. The activating of 25% GGBS with 75% CKD provided the optimum binder which increased the mechanical strengths by about 6 times than untreated soil. SEM revealed substantial formations of C-S-H and C-A-H gel, along with ettringite, intensifying with time. This research provides viable outcomes for stabilizing clay soil using environmentally friendly binders, demonstrating significant improvements in soil properties, particularly when using the binary activated blended binder consisting of GGBS and CKD.Graphical

Predictive Pattern of Undrained Shear Strength in Stabilized Sulfur Rich Silty Soil Based on Binder and Initial Mixing Water Content

A laboratory investigation was conducted to identify principal variables-initial mixing water content, porosity, and binder content- impacting undrained shear strength (qu) of stabilized sulfur-rich silty soil. An equation for predicting qu of stabilized soil was established based on the experimental data. Initially, samples were prepared with soils sample with different initial water and binder contents. Multicem, a binder consisting of a mix of cement and cement kiln dust, was added to the samples. Three different percentages of Multicem were mixed at five different soil water contents to measure qu of stabilized mixtures to understand how water content and porosity levels in the samples affect the performance of the binder and their combined impact on the strength of the samples. The soil-binder mixtures were compacted and subsequently cured in laboratory-controlled environment. The prepared samples were tested in uniaxial compression test apparatus. The results evidenced that binder content and corresponding porosity affect the strength of specimens at an equal water content. The results showed that at equal initial mixing water content, the qu of a sample increased by increasing binder content. Furthermore, it was observed that increase of binder content has a reverse effect on porosity. It was appeared lowering the soil water content, initially increased the strength until an optimum water content. Further lowering water content increased the porosity and consequently decreased qu of samples. Moreover, a ratio of porosity/volumetric binder content was chosen to evaluate the impact of these two variables on strength of samples. This study showed that qu is an exponential function of porosity/binder volumetric content ratio which depends on initial mixing water content of mixtures. It was shown at water content lower than the optimum, results of stabilization are more effective than in soil at higher water contents. Therefore, reducing the water content and thereby porosity has more significant effect on improving qu than increasing the binder content.

Comparative life cycle assessment of landfill sludge treatment technologies in China.

Reasonable treatment of large amounts of sludge excavated from landfills has gained increasing attention due to the diminishing availability of landfill space in China. In this study, five landfill sludge (LS) treatment technologies using life cycle assessment (LCA) and life cycle cost (LCC) were investigated, i.e., co-incineration in coal-fired power plants (CFPP) and waste incineration power plant (WIPP), co-processing in cement kiln, bricks production, and sintering ceramsite. The LCA results demonstrate that sintering ceramsite outperforms other technologies and LCC results indicate sintering ceramsite also provides the highest economic benefit ($869.94). To further enhance environmental and economic performances of the LS treatment, the substitution of coal with natural gas and biomass can reduce Energy Conservation and Emission Reduction (ECER) index by 74% and 98%, respectively. This substitution can increase economic returns by 24% and 26%, respectively. Furthermore, national-level economic benefit and carbon emission reduction potential of different LS treatment technology alternative scenarios were assessed. Results display that a combination of 50% CFPP, 25% bricks, and 25% ceramsite (biomass) offers the highest economic gain, which is 3.02 times that of 50% CFPP and 50% cement (original case). Conversely, the replacement of 25% brick with 25% cement in the above combination result in the lowest carbon reduction, which is 9.35 times that of the original case.

Effect of Surface Hydrophobization on the Durability of Concrete with Cement Kiln Dust

Effect of Surface Hydrophobization on the Durability of Concrete with Cement Kiln Dust

Using a Laboratory Model Test to Assess the Collapsibility of a Gypseous Soil Improved with Geogrid and Cement Kiln Dust

Using a Laboratory Model Test to Assess the Collapsibility of a Gypseous Soil Improved with Geogrid and Cement Kiln Dust

Adsorption of 2,4-Dichlorophenoxyacetic Acid Herbicide from Aqueous Solution by Using Cement Kiln Dust Solid Waste

Adsorption of 2,4-Dichlorophenoxyacetic Acid Herbicide from Aqueous Solution by Using Cement Kiln Dust Solid Waste

Deeply revealing the mechanism of the synergistic effect of Cu and P on alleviating CaO poisoning performance of V-W-Ti catalysts in cement kilns

CaO was the inevitable cause of V2O5-WO3-TiO2 catalyst (VWTi) poisoning in cement kilns. The significant reduction in NO conversion was due to the combination of CaO and active species of the vanadium-based catalyst. In this work, the VWTi catalysts were modified with different contents of Cu and P to improve resistance to CaO, thereby extending the service life of catalysts in cement kilns. By doping Cu and P, the Ca-VWCu3P5Ti had better catalytic activity, reduced the poisoning effect of CaO to V5+, thus protecting the redox properties and increasing the surface acidic sites of the catalyst. Meanwhile, the in-situ DRIFTs results showed that the poisoning effect of CaO was weaker on the Ca-VWCu3P5Ti than that of the Ca-VWTi. In addition, the NH3 and NO species could be effectively adsorbed and activated on the surface of the Ca-VWCu3P5Ti by E-R mechanism. In this way, the harm of CaO to the vanadium-based catalysts was effectively reduced. This work provided a promising strategy to design vanadium-based catalysts with superior resistance to CaO in NH3-SCR reaction.

Comprehensive Analysis of Industrial Solid-Waste-to-Energy by Refuse-Derived Fuel Technology: A Case Study in Shanghai

The prolific generation of industrial solid waste (ISW) in China, coupled with its complex composition, presents significant challenges due to exceeding environmental capacity. Identifying an appropriate approach to maximize the use of ISW, particularly low-value industrial solid waste (LISW), is crucial for addressing environmental issues. This study explores the potential of converting LISW into refuse-derived fuel (RDF), an energy-rich precursor, as a promising method for disposal and reutilization. The advantages of RDF lie primarily in two key areas: management and technology. Regulatory aspects cover principles governing RDF feedstock preparation, storage and transportation requirements, and pollutant emission regulations. Technical considerations include pretreatment techniques, additive selection, and analyzing RDF as a substitute for fossil fuels. To assess the effectiveness of RDF technology in harnessing the remaining energy from LISW, this paper provides an overview of relevant national laws and regulations concerning incineration plants, guiding the utilization of RDF in such facilities. Additionally, using Shanghai as a case study, we evaluate the ISW situation, domestic waste incineration plants, and cement kiln plants to identify potential scenarios for RDF application in future energy systems. Our findings suggest that LISW holds significant potential as a power plant fuel, particularly when blended with higher calorific value materials to produce RDF particles with exceptional combustion performance, density, and storage characteristics.