Clay Products Research Articles

Characterization of Ceramic Tile Bodies Prepared From Clays Collected from Four

Sierra Leone has high potentials for the setting-up of ceramic industry because of its huge virgin deposits of raw materials, chiefly clay, but lacks the technological know-how to utilize these materials to an economically sound level. Tile body offers a foundation for the performance of a glaze. The chemical and mineralogical composition of these clay bodies coupled with some physical properties, such a plasticity, bulk density, porosity, and water absorption, play significant role in determining the quality of the glazed surface.This is attested by certain glaze defects like pinholes, crazing and crawling on the glaze surface resulting mainly from bubble development within the body matrix during firing. The study aims at contributing to the promotion and use of appropriate ceramic building materials technology in Sierra Leone, by providing relevant research data to guide the production of quality ceramic products. The three key objectives, were to determine (1) the physical properties (2) chemical properties (3) mechanical properties of the clay samples investigated for their suitability in clay tile bodies production. Clay samples were collected from four sites in Sierra Leone namely Matankay (C-M) in the Western Rural District, Bo (C-B) in Bo District, Koribondo (C-K) in Pujehun District and Yele (C-Y) in Tonkolili District. Based on their plasticity index values, grain size distribution, bulk density, porosity and dry-fired shrinkage results obtained from this study, the four clay samples investigated are suitable for clay tile body production provided grog, frits, fluxes and other components are added proportionately and fired at temperatures above 1100oC to improve vitrification of the clay tile body during biscuit firing before application of the glaze.

Bayesian inference of coupled groundwater flow and radiogenic helium-4 production and transport at the catchment scale

Hydrogeological numerical models are essential for assessing radioactive waste disposal by understanding groundwater flow systems. These models typically rely on hydraulic head data, with other state variables often underutilized in model inversions. In Flanders' Neogene aquifer, where safety studies for Boom Clay are ongoing, existing models face uncertainties due to dependence on hydraulic heads alone. This study aims to: i) develop a conceptual model of radiogenic Helium-4 (4Herad) production and transport to reproduce observed concentrations; ii) evaluate the usefulness of 4Herad observations as an additional state variable for inverse conditioning; and iii) assess how including 4Herad affects model calibration and uncertainty reduction. We address these objectives by incorporating radiogenic Helium-4 (4Herad) as an unconventional state variable in model inversion to tackle parameter non-uniqueness. Utilizing a Bayesian approach, we employ two 3D models: a groundwater flow (GWF) model conditioned by hydraulic heads and a coupled GWF model with 4Herad production and transport, conditioned by both hydraulic heads and 4Herad concentrations. We hypothesize that integrating 4Herad will improve model accuracy and reduce uncertainties compared to using hydraulic head data alone. Findings indicate that major 4Herad sources include crustal fluxes (~57 %) and in situ Boom Clay production (~25 %). The coupled inference narrows the posterior distributions of parameters, especially for hydraulic conductivity (e.g., Mol, Diest, Berchem formations, and the Rauw Fault) and recharge, showing that 4Herad observations effectively reduce uncertainty beyond hydraulic head data. Including 4Herad improves model reliability and prediction accuracy, highlighting its importance for refining groundwater flow parameters and derived fluxes. To the best of our knowledge, this study marks the first-ever attempt at harnessing 4Herad quantitative insights into flow and transport parameters following a Bayesian approach at a catchment scale, setting a precedent for future research and emphasizing the innovative nature of this work. This study showcases a state-of-the-art approach in hydrogeological modelling, demonstrating the effectiveness of integrating 4Herad with hydraulic head observations to produce more reliable model predictions. By reducing uncertainties in crucial groundwater fluxes, this approach offers significant potential for improving geological disposal safety studies. This pioneering work advocates for the continued use of 4Herad in hydrogeological modelling, emphasizing its innovative contribution to future research and safety studies. Plain language summaryUnderstanding how groundwater flows is crucial for safely storing radioactive waste. Traditionally, models used to study groundwater rely mostly on measurements of water pressure, while other valuable data often go unused. In the Neogene aquifer in Flanders, where researchers are studying the Boom Clay formation for potential waste storage, relying only on water pressure has created uncertainties in the models. This study explores a new approach by using a different type of measurement: radiogenic Helium-4 (4Herad). The goals of the study are threefold: first, to build a model that accurately represents how 4Herad is produced and moves through the groundwater; second, to test whether including 4Herad as an additional measurement improves the model compared to using only water pressure data; and third, to see how using 4Herad affects the accuracy and reliability of the model. The study uses two types of models: one that relies only on water pressure data and another that includes both water pressure and 4Herad measurements. The idea is that 4Herad could provide additional insights and help reduce uncertainties in the model. The findings show that 4Herad comes mainly from two sources: the surrounding crust and the Boom Clay itself. Including 4Herad in the model helps narrow down uncertainties, particularly regarding how water moves through different layers and how much water is being replenished. This research is the first to use 4Herad in this way, using a formal statistical method to improve groundwater models. The results suggest that 4Herad is a valuable addition for making more accurate predictions and improving safety assessments for radioactive waste storage.

Eficiencia del ladrillo utilizando mezcla de arcilla y residuos de vidrio como agregado fino en los procesos constructivos del municipio de Valledupar – Cesar

Este proyecto evaluó el uso de vidrio molido como agregado fino en la elaboración de ladrillos bocadillos, con el fin de reducir el impacto ambiental y aprovechar residuos. Se probaron tres dosificaciones de vidrio (15%, 25%, 35%) como reemplazo parcial de la arcilla, realizando ensayos de granulometría, límites de consistencia, humedad natural, absorción y resistencia a la compresión. Los resultados mostraron que la mezcla con 15% de vidrio es la más eficiente, ya que conserva las propiedades del ladrillo (forma, textura, color) y cumple con las normativas NTC 4017 y NTC 4205, sin afectar su calidad. The production of bricks and other clay products has become an ecological problem generating a high impact from the proper management of solid waste to the extraction of raw materials. In order to mitigate this problem, different studies have been carried out to take advantage of non-conventional aggregates. This project studied the influence of ground glass as fine aggregate in the production of sandwich bricks. Glass is used as a replacement for clay using different dosages (15%, 25%, 35%), thus taking advantage of materials that were previously discarded and reducing the use of natural raw materials. The main objective of this project is precisely to evaluate the mixture of waste glass as fine aggregate together with clay for the subsequent manufacture of bricks according to the established regulations. Several laboratory tests were carried out on the raw material, such as: granulometry, consistency limits and natural humidity. Likewise, tests such as absorption and compressive strength were carried out on the prototypes made. With this information, the final product was characterized based on NTC 4017 and NTC 4205 standards. As for the results, it was identified that the dose of ground glass with lower concentration (15%), has more relevant effects on the final product, the shape, texture and color are not modified with the presence of ground glass.

Toward integrated dam assessment: evaluating multi-dimensional impacts of the Grand Ethiopian Renaissance Dam on Sudan

Abstract The Grand Ethiopian Renaissance Dam (GERD) on the Nile is expected to influence many ecosystem services, such as flood regulation, hydro-electricity production, food supply, and habitat provision, among others. Understanding these impacts (positive and negative) requires a comprehensive evaluation framework. This study develops and applies an integrated simulation framework for assessing the impacts of the GERD on Sudan, focusing on the simultaneous economywide effects of riverine flood hazards, irrigation water supply, hydropower generation, and floodplain-dependent industries, namely traditional fired clay brick production. The simulation framework incorporates three models: a river infrastructure system model, a flood model, and a Computable General Equilibrium Model. Results indicate positive impacts for hydropower generation and flood control, marginal benefits for water supply to existing irrigation, and negative consequences for brick production and the construction sector. Assuming that the GERD starts its long-term operation in 2025, we find an overall positive economic impact on Sudan’s Gross Domestic Product in 2025, with an increase of up to just over 0.1%, subject to river flow conditions. Recognizing the differences in impacts across sectors and income groups, the study emphasizes the need for interventions that ameliorate negative effects. While the study captures several impacts, other effects on the environment, recession agriculture, and soil fertility require further investigation. Still, our findings underscore the importance of adopting an integrated simulation approach to dam evaluation, acknowledging the interconnected nature of water and related sectors in national economies.

Population status and ecology of the globally threatened liverwort Marsupella profunda Lindb. in Britain

ABSTRACT Introduction Marsupella profunda Lindb. is known from Britain, Portugal and Macaronesia. Its population status and ecology in Britain were investigated. Methods An inventory of records of Marsupella profunda was prepared, and surveys were conducted at a subset of sites. Population size was measured by counts of ‘individual-equivalents’, defined as occupied 1 m grid cells. Habitat and community composition were recorded by relevés. Key results and conclusions Marsupella profunda is confined to habitat created by china clay quarrying, and mostly occurs on kaolinised granite. It is one of the earliest colonists of this substrate. The longevity of habitat patches is limited mainly by competitive exclusion by other bryophytes and excessive shade from scrub development. It has been recorded from six sites in West Cornwall but presently survives at only one of these, where it will likely become extinct within the next 20 years due to vegetation succession. In East Cornwall, an enormous complex of active and disused quarries within the St Austell China Clay Region supports a large population (10,000–20,000 individual-equivalents), but this is declining because china clay production has decreased greatly over the past 30 years. Attempts to conserve the species by the special protection of areas of land have failed because the quarrying process that originally supplied fresh suitable substrate no longer operates in these areas, habitat management measures have been insufficient, and scrub development has progressed. The future of the species in Britain depends on the uncertain future of commercial quarrying in areas of kaolinised granite in Cornwall.

Life cycle assessment of limestone calcined clay concrete: Potential for low-carbon 3D printing

Limestone calcined clay cement is being promoted throughout the construction industry as a way to considerably reduce the cement proportion in concrete mixtures. At the same time, concrete 3D printing could save resources by placing concrete material only where its functionalities are maximized. This study addresses the need for a quantification of the environmental impacts related to the material acquisition phase regarding a low-clinker 3D printing material.Compared to a 30 MPa 3D printing material from the literature, a 3D printable LC3-based concrete with low clinker content in the Quebec context displays a 36 % climate change score reduction with the same compressive strength (46 % reduction in the French context). A small impact shift is noticed in 6 out of 16 midpoint indicators (5 in the French case), mainly due to the calcined clay production. However, it is offset by the significant reduction in other indicators when considering an endpoint assessment. When considering different sourcing scenarios, a global warming potential variability of up to 15 % is observed.LC3 remains a viable solution for the mitigation of greenhouse gas emissions in the context of concrete 3D printing as it provides mechanical strength and enhanced structuration rate for low-clinker materials. However, a specific attention should be accorded to the calcined clay plant locations, especially when the calcined clay content is higher than the value used in this study. As a perspective, a mix design tool could allow the optimization of environmental impacts depending on expected fresh and hardened properties.

Application of Nanofibrous Clay Minerals in Water-Based Drilling Fluids: Principles, Methods, and Challenges

Nanofibrous clay minerals, specifically palygorskite (Pal) and sepiolite (Sep), have been becoming a new generation of rheological additives for drilling fluid systems due to their unique nanostructure, high performance, environmentally benign nature, and cost-effectiveness. These nanoclay minerals exhibit excellent colloidal and rheological properties in aqueous systems, even in saline and high-temperature environments. Although Pal and Sep have been employed as auxiliary rheological additives in a few cases to enhance the salt resistance of conventional water-based drilling fluids (WBDFs), these two clay minerals have not yet been used on a large scale due to a lack of understanding of their structures and properties, as well as the control of their performance. This paper presents a comprehensive review of the clay mineralogy, colloidal chemistry, rheological behaviors, and filtration properties of nanofibrous clay minerals in WBDFs, with critical comments. It also discusses the challenges and prospects for further research. This review provides new insights into fundamental and applied studies of nanofibrous clay minerals and helps promote the large-scale application of nanofibrous clay products in drilling fluids.

Profiling of Tayammum Clay Product in Malaysia by Spectroscopic-Chemometric Approach

Tayammum is a dry purifying method that uses earthen materials, mostly clay. The technique is applied when there is no access to water or in specific circumstances, such as when a person has susceptible skin on water. In tayammum, Islamic law describes clay as pure dust or soil used as a cleansing agent. Nevertheless, no scientific report examined the components of clay present in tayammum clay. Therefore, this study aimed to characterise and profile the mineral composition of tayammum clay, which is a commercially available product in Malaysia. Twelve commercial clay samples and one representative sample were analysed by ATR-FTIR spectroscopy in the range of 4000 to 600 cm-1. PCA exploratory analysis clearly demonstrated the differentiation of the tayammum clay product into seven groups according to its functional group. Following the FTIR analysis, the samples underwent examination using X-ray diffraction (XRD) and X-ray fluorescence (XRF) spectrometers further to identify the mineral and element composition of the clay, respectively. The XRD analysis indicated that there were possibly four types of mineral powder commonly distributed in the market for Tayammum purposes which are three types of clay: palygorskite, kaolinite, and phengite, and another one is zeolite-type: Na-heulandite. All four of them are common materials used for adsorbent and cleansing purposes.

Fly Ash and Rice Husk Ash Utilization to Enlarge Clay Brick Dimension

Burnt clay bricks, mostly used as non-structural wall unit materials in Indonesia, contain only clay in Bengkulu Province. A large amount of clay is used during clay brick production as a shrinkage effect of burning, while clay is a limited natural resource. Available non-plastic materials that can withstand combustion contraction are required to reduce the use of clay. Ash materials like fly ash and rice husk ash are non-plastic materials. The purposes of this research are to reduce clay usage, enlarge dimensions, and improve brick performance at the same time by adding coal fly ash (FA) and rice husk ash (RHA). This research is an experimental study of FA clay brick (FCB) and a combination of 50% FA and 50% RHA clay brick (FRCB). The ash was added to the mixture at weights of 10%, 20%, and 30% of clay. The factory-specified production method was used to create bricks. After the materials and water meltdown process to produce plastic material, bricks were molded, dried, and burned. Green and burnt brick measurements and weights were gathered. The Brick Indonesian Standard Code (SNI 15-2094-2000) was used while determining the bricks' compression strength and absorption. The mean values of the quantitative data were used after being analyzed through coefficient of variation values less than 10%. The result shows that the compressive strengths and absorption of 10% and 20% of the ash content of FCB meet the Indonesian code. Both brick volumes expand as the ash content increases. FRCB volume weight is 11%, 7.8%, and 8.1% lighter than FCB for 10%, 20%, and 30% ash content, respectively. Both brick varieties meet the ASTM code for nonload-bearing concrete masonry units. The use of FA and a mixture of FA and RHA enhances shrinkage, increases brick dimensions, and simultaneously lowers brick weight. Using lighter and larger bricks for the walls helps to recycle waste, reduce the mass of the building, and reduce the use of clay resources. Application 10% and 20% fly ash is recommended for increasing the size of clay bricks in Bengkulu Province, Indonesia.

Site-Independent Mapping of Clay Content in Vineyard Soils via Mobile Proximal Gamma-Ray Spectrometry and Machine Learning Calibrations.

Vineyards hold considerable soil variability between regions and plots, and there is frequently large soil heterogeneity within plots. Clay content in vineyard soils is of interest with respect to soil management, environmental monitoring, and wine quality. However, spatially resolved clay mapping is laborious and expensive. Gamma-ray spectrometry (GS) is a suitable tool for predicting clay content in precision agriculture when locally calibrated, but it has scarcely been tested site-independently and in vineyards. This study evaluated GS to predict clay content with a site-independent calibration and four machine learning algorithms (Support Vector Machines, Random Forest, k-Nearest Neighbors, and Bayesian regulated neuronal networks) in eight vineyards from four German vine-growing regions. Clay content in the studied soils ranged from 62 to 647 g kg-1. The Random Forest calibration was most suitable. Test set evaluation revealed good model performance for the entire dataset with RPIQ = 4.64, RMSEP = 56.7 g kg-1, and R2 = 0.87; however, prediction quality varied between the sites. Overall, GS with the Random Forest model calibration was appropriate to predict the clay content and its spatial distribution, even for heterogeneous geopedological settings and in individual plots. Therefore, GS is considered a valuable tool for soil mapping in vineyards, where clay content and product quality are closely linked.

Evaluating Technical properties of fired clay Brick production with mosaic sludge: A comprehensive study on heavy metal leachability for sustainable environmental and economic benefits

Mosaic sludge, generated from mosaic industrial activities such as cutting, polishing, and grinding, is often disposed of in landfills or discharged into drainage systems without adequate treatment. This study aims to reuse mosaic sludge from the mosaic industry by incorporating it into fired clay bricks. This approach offers an alternative disposal method, improves brick quality, and minimizes heavy metal leachability, contributing to environmental and economic sustainability. X-Ray Fluorescence (XRF) was conducted to determine the heavy metal concentration from two types of mosaic sludge bodymill mosaic sludge (BS) and polishing mosaic sludge (PS). The result indicates that the highest element concentration in mosaic sludge (BS and PS) shows that barium is the highest with 3253 ppm and 3260 ppm. Meanwhile, the lowest element concentration obtained in BS and PS is cesium with 14 ppm and 17 ppm. SPLP and TCLP also conducted in this study and the result show that, even though the element such as ferum (Fe) and cadmium (Cd) was not detected in XRF but in SPLP and TCLP, it shows that these two elements exist in clay, BS and PS with low concentration. In order to evaluate the compressive strength conducted by incorporating with different proportions 0 %, 1 %, 5 %, 10 %, 20 % and 30 % of BS and PS into fired clay brick. The result shows that compressive strength BS brick was stronger than PS brick. The maximum sludge percentage used in BS brick is 5 % with value of compressive strength is 28.10 MPa. Meanwhile, PS brick had the higher value of compressive strength at 30 % sludge percentage with the value 23.46 MPa. Static Leachate Test (SLT) was performed to evaluate heavy metal leachability from bricks containing different proportions of BS and PS sludge. In the SLT results, Fe exhibits the highest concentration of heavy metals at various proportions of BS and PS: 2.11 mg/L and 2.27 mg/L at 1 %, 1.77 mg/L and 1.88 mg/L at 5 %, 2.34 mg/L and 3.29 mg/L at 20 %, and 2.79 mg/L and 3.64 mg/L at 30 % respectively, among other elements. On the other hand, elements including Cr, Ni, Cu, As, Cd, and Pb demonstrated lower concentrations ranging from 0.00 mg/L - 1.0 mg/L. The result for control brick, BS brick and PS brick shows the same pattern. However, overall results show that the concentration still under limit set by USEPA.

Effective sludge management: Reuse of biowaste and sewer sediments for fired bricks

ABSTRACT This study partially replaced the clay with sewer sludge (SS) and rice husk (RH-SS) to make fired bricks. The brick samples were examed in terms of shrinkage, water absorption, and compressive strength. Besides, they were analyzed via XRD and metal extraction to determine the heavy metal residuals in the products. The results showed that it was possible to fabricate fired bricks using sewer sludge or rice husk-blended sludge with up to 30% by weight. These brick samples complied with the technical standard for clay brick production, in which the compressive strength was more than 7.5 MPa, water absorption was from 11–16%, and the linear shrinkage was all less than 5%. The rice husk addition helped mitigate the heavy metal residuals in the bricks and leaching liquid, in which all the values were lower than the US-EPA maximum concentration of contaminants for toxicity characteristics. Implications: Previous studies have proved the possibility of mixing sewage sludge from different origins (sewage sludge, river sediment, canal sediment, sewer sediment, etc.) with clay and some wastes to make bricks. In which, mostof the studies used sewage sludge from wastewater treatment plants, very fewdealt with lake/river or sewer sediment. This study shall be the first to study the possibility of employing sewer sediments with the addition of rice husk powder to achieve two targets, including (1) the reuse of biowaste and sludge for brick fabrication and (2) the reduction of heavy metals in final calcined bricks. Different ratios of the rice-husk blended sewer sludge (RH-SS) – clay mixture shall be tested to find the optimized compositions. The results showed that it was possible to fabricate fired bricks using sewer sludge or rice husk-blended sludge with up to 30% by weight, which meant reduce 30% of clay in the brick production. The final products were proved to meet the quality standard in terms of compressive strength (more than 10 MPa), water absorption(from 11–16%), and the linear shrinkage (less than 5%). Larger scale of this study can be an evident to recommend for policy change in the waste reuse in construction field.

Soils on Recent Tephra of the Somma–Vesuvius Volcanic Complex, Italy

The Somma–Vesuvius volcanic complex emitted huge quantities of volcanic materials over a period from before 18,300 years BP to 1944. The activity during the last period, from post-AD 1631 to 1944, primarily produced lava and pyroclastics via effusive and strombolian eruptions. We investigated the pedogenesis on rocks formed from post-AD 1631 to 1944, occurring on the slopes of Mt. Vesuvius up to Gran Cono Vesuviano and in the northern valley separating Vesuvius from the older Mt. Somma edifice. Pertinent morphological, physical, chemical, and mineralogical (XRD and FT-IR) soil properties were studied. The results indicated the existence of thin and deep stratified soils on lava, as well as the presence of loose detritic covers formed via pyroclastic emplacement and redistribution. The soils showed minimal profile differentiation, frequently with layering recording the episodic addition of sediments. We found that the dominant coarse size of primary mineral particles was preserved, and there was a low level of clay production. The main mineralogical assemblage present in sands also persisted in clays, indicating the physical breaking of the parent material. Chemical weathering produced mineral modifications towards the active forms of Al and Fe and was also attested in selected soils by glass alteration, allophane production, and the presence of analcime in clay as a secondary product from leucite. The differences in glass alteration and analcime production found in the selected soils on lava were related to soil particle size and soil thickness. Concerning the youngest soil present on Gran Cono Vesuviano, other factors, such as the substratum’s age and site elevation, appeared to be implicated.

Advancements in Expanded Clay Manufacturing Using "Clay-Desert Sand-Oil Sludge" Sludge Composite Materials

This study explores the development of resource-saving expanded clay technology utilizing underutilized clay raw materials and oil extraction waste. Traditional expanded clay production is energy-intensive and often employs high-quality clay; however, our research identifies technological modes and parameters for producing expanded clay through plastic molding, incorporating substandard raw materials and oil sludge. This method eliminates the need for costly energy-releasing additives and reduces energy costs associated with drying and firing by 25-30%. The research aims to demonstrate the feasibility of this novel production technique in the Republic of Kazakhstan, considering the local availability of raw materials, energy resources, and regional demand for thermal insulation materials in industrial and civil construction. Our findings suggest that integrating 'Desert Sand-Oil Sludge' into the batch composition can effectively produce granulated porous thermal insulation material, aligning with the region's development strategy and offering significant economic and environmental benefits.
 Highlights:
 
 Resource Utilization: Uses oil waste and substandard clay to produce expanded clay, reducing reliance on high-quality materials.
 Energy Savings: Cuts energy costs for production by 25-30% through innovative processing.
 Regional Benefit: Aligns with Kazakhstan's strategy by utilizing local resources and supporting construction needs.
 
 Keywords: Expanded Clay, Oil Sludge, Desert Sand

Plastisols based on polyvinyl alcohol and their use for the production of children’s products

In this work, plastisol compositions have been developed for the production of plastic masses based on chemically cross-linked polyvinyl alcohol and polymer expanded microspheres for the production of air clay

Empowering MSMEs clay and doll products: Navigating digital marketing challenges in the digitization era

The digitization era is compelling UMKM clay and doll products in the Waru sub-district, Sidoarjo Regency, to transition from traditional to digital marketing strategies. However, they encounter challenges in digital marketing due to a lack of e-commerce knowledge. To tackle this issue, community engagement activities are conducted to enhance product marketing, expand market share, and increase income. The approach used involves training and assistance in digital marketing creation, which includes several stages such as surveys, data collection through interviews, solution formulation, and program evaluation. With the implementation of these assistance activities, UMKM clay and doll products in the Waru sub-district, Sidoarjo, can execute marketing strategies through digital platforms like Google Maps and the Shopee marketplace. This not only facilitates consumers in accessing information about UMKM products but also enriches their understanding of digital marketing.

DFT study on the polyol sacrificial agents for improved clay tolerance of polycarboxylate superplasticizers

With the gradual scarcity of high-quality sand and gravel resources, the increasing mud content in concrete aggregates could strongly adsorb on polycarboxylate superplasticizers (PCE), greatly reducing their working performance. Modifying the molecular structure of PCE or compounding sacrificial agents can effectively improve the tolerance to clay minerals. In this article, using different small molecule polyols and polypropylene glycol (PPG) as examples, density functional theory (DFT) was employed to simulate the adsorption between clay minerals and hydration products. This exploration aims to further understand the anti-clay performance of various sacrificial agents from the perspective of adsorption energy. Ca-montmorillonite (CaMMT) exhibits the lowest adsorption energy among different clay minerals, making it the preferred site for sacrificial agent adsorption. With an increase in hydroxyl number, the adsorption energy between polyol sacrificial agents and montmorillonite decreases. Among polymeric polyols, the adsorption energy between PPG 600 and montmorillonite is the lowest (-10.86 eV), indicating superior anti-clay performance by preferentially occupying active sites on montmorillonite. As the interlayer spacing of montmorillonite increases, the adsorption energy between PPG 600 and montmorillonite initially decreases and then increases, reaching the lowest value at c=15.5 Å. There are more electron transfers (0.858) compared to the electron gain and loss, confirming more interaction between the sacrificial agents and montmorillonite at 15.5Å. This article also provides a crucial theoretical basis for the structural design of anti-clay sacrificial agents, offering insights into addressing compatibility issues between PCEs and clay minerals.

Development of sustainable masonry solid blocks by the incorporation of industrial and agro waste.

<p>Bricks have been extensively adopted for centuries and continue to play a vital role in the construction industry. Nevertheless of its dependable workability and accessibility, fired clay brick production has been recognized for its comparatively high energy and resource requirements. Traditional clay bricks, widely used in construction for centuries, pose significant environmental challenges. The extraction of clay for brick production can result in habitat destruction and landscape alteration. The firing process in brick kilns consumes substantial amounts of energy, often derived from non-renewable sources, contributing to greenhouse gas emissions. The development of sustainable masonry solid blocks signifies a revolutionary change in the construction sector, providing a sustainable substitute for conventional building materials. These blocks, typically made from reused or locally obtained materials, demonstrate a dedication to environmental stewardship and the efficient use of resources. This innovative idea of utilizing some industrial waste such as fly ash, bagasse ash, marble dust and stone dust in solid block manufacture significantly reduces the environmental pollution problem, offers an alternative construction material source, and makes the solid blocks economical. Different types of trail mixes have been developed, and the produced masonry solid blocks underwent a series of experimental investigations. The solid bricks are being compared to conventional cement blocks. The developed sustainable solid block (MB6) exhibits a strength that is 43.78% greater than that of conventional cement solid blocks. The present study attempts to determine the optimal material proportion for innovative solid block production. Key words: Carbon footprint, Eco-friendly building blocks, Bagasse ash, Marble dust and Industrial waste</p>

Effect of the Side-Chain Length in Polycarboxylic Superplasticizer on the Competition Adsorption in the Presence of Montmorillonite: A Density Functional Theory Study.

Polycarboxylic superplasticizers (PCEs) exhibit numerous advantages as concrete additives, effectively improving the stability and strength of concrete. However, competitive adsorption of PCEs occurs in the presence of clay, which may affect the cement dispersion and water-reducing performance. Extensive research has been conducted on the physical and mechanical properties of PCEs; however, the effect of the diverse structures of PCEs on the competitive adsorption on clay and cement hydration products has been rarely studied. This study employs Ca-montmorillonite (CaMMT) as a clay representative, by constructing adsorption models of PCEs on CaMMT and cement hydration products. A comparison of the adsorption energies considering different side-chain lengths of PCEs is included. Typically, the adsorption energy on CaMMT is lower than that on hydration products, leading PCEs to preferentially adsorb on the clay, thereby reducing its effective dosage in the cement particles. The challenge of PCE adsorption on CaMMT increases with the polymerization degree, and methylallyl polyoxyethylene ether (HPEG) exhibits lower adsorption energies on CaMMT. The density of states (DOS) analysis indicated the highest peak values of allyl polyethylene ether (APEG) as well as the peak area at n (polymerization degree) = 1. The total number of transferred electrons for APEG was 0.648, surpassing those of other PCEs. The interaction mechanism of PCEs with clay and hydration products is further elucidated through electronic gain/loss analysis, also providing a basis for the theoretical analysis on how to reduce the adsorption of PCEs on clay and the structural design of mud-resistant PCEs.

Effects of Wastewater Sludge Addition on Fired Clay Bricks: Enhancing Performance and Sustainable Construction Practices

This study explores the impact of incorporating wastewater sludge into fired clay bricks to improve their performance and promote sustainable construction. Physical, mechanical, and environmental properties of the sludge-amended bricks are investigated to assess their suitability as an alternative construction material. Lab tests are conducted to characterize the sludge and clay, and brick samples with varying sludge content are produced. Physical properties such as water absorption, are analyzed to determine the influence of sludge addition on the bricks' structural characteristics. Mechanical tests, including compressive and flexural strength evaluations, assess the performance of the sludge-amended bricks compared to traditional clay bricks. Additionally, environmental aspects are considered to evaluate the sustainability of the sludge-amended bricks. Life cycle assessment and carbon footprint analysis quantify the environmental benefits and drawbacks associated with their production and use. The findings of this study contribute to the knowledge of sustainable construction materials by exploring the potential utilization of wastewater sludge in fired clay brick production.