Neshable Noel, Tommy Mielke, Gustave Semugaza
et al.
This paper aims to provide a thorough comprehension of the chemical transformations occurring during the thermal preparation of reactivated virgin cements (RVCes). X-ray Diffraction (XRD) analysis of RVCes reveals the reformation of the di-calcium mineral phases in two polymorphic forms: α/L-C2S and β-C2S, within the temperature range from 600 °C to 850 °C. We exactly quantify the two polymorphs α/L-C2S and α/H-C2S and distinguish their presence in the reactivation temperature range. This phase formation is corroborated by scanning electron microscopy (SEM) coupled with energy-dispersive X-ray spectroscopy (EDX). We further investigated the chemical changes that, after re-activation, take place during the 28-day rehydration period using differential scanning calorimetry (DSC), thermogravimetry (TG), XRD, and SEM, confirming the reformation of the typical hydration mineral phases. Mercury intrusion porosimetry (MIP) and compressive strength tests verified the development of strength-enhancing mineral phases in RVCs, exhibiting a mechanical strength recovery ranging from 50 % to 75 % compared to industrially produced virgin cement (VCe).
Valeria V. Strokova, Ekaterina N. Gubareva, Yulia N. Ogurtsova
et al.
Subsurface use waste accounts for the overwhelming majority of waste generated and accumulated in Russia. The increase in the volume of processing of minerals by the mining and processing industries leads to an aggravation of environmental problems – the negative impact of overburden dumps, tailings of enrichment and processing of mineral raw materials on the environment is increasing. Using the example of three types of rocks, the possibility of using carbonate subsurface use waste as raw materials in the formation of photocatalytic composite materials (PCM) in the production of building materials and products, and simultaneously solving environmental problems of territories through large-scale utilization of man-made waste, is considered. A complex of physical (porosity, specific surface area, dispersion, surface morphology) and chemical (chemical composition, acid-base centers, zeta potential, hydrogen index) studies of the properties of carbonate materials of various genetic types have been carried out to determine the possibility of their use as a substrate in the production of PCM. The photocatalytic material obtained by depositing sol-gel synthesized titanium compounds onto a mineral carrier is intended for incorporation into cement building composites and for giving them self-cleaning properties during operation. The mineral powders of limestone from the Tyushevskoye (T) and Porechenskoye (P) deposits and marble from the Polotskoye deposit were ranked according to certain requirements – dispersion, porosity, and adsorption activity. The establishment of numerical indicators for each type of raw material made it possible to determine the degree of suitability of mineral powders of carbonate rocks for the production of composite materials introduced into the composition of building materials. A ranking of mineral powders was carried out to increase the potential efficiency of use in the composition of PCM in the following sequence: limestone T → limestone P → marble. PCM based on carbonate carriers exhibit high rates of organic pollutant degradation (more than 90 %) and are applicable as photocatalytic agents.
Hossein Mehrjoo, Yousef Kazemzadeh, Ismail Ismail
et al.
Abstract Colloidal gas aphrons (CGAs) are characterized by their multi-layered, stable bubbles, encased within thin surfactant films. Their remarkable stability, due to the presence of a delicate surfactant shell, has made them a versatile and transformative solution across various industries, particularly in the oil industry. This paper presents an extensive literature review, focusing on the wide-ranging applications of CGAs, with a particular emphasis on their use in the petroleum industry. By exploring diverse areas, we highlight their potential in drilling operations, cementing, completion and workovers, as well as enhanced oil recovery (EOR). The exploration of CGA applications in these domains addresses major industrial challenges, including those related to drilling high-angle and horizontal wells, filtration loss, heavy-weight cement systems with high density, fluid leak-off, circulation efficiency in dead wells, static fluid conditions, and more. This comprehensive review underscores the transformative potential of CGAs in the petroleum industry, offering a holistic perspective on their multifaceted applications and pivotal role in advancing contemporary energy research.
Lakman Prabu P.S., Vivek S.S., Karthikeyan B.
et al.
Self-compacting concrete is used as critical reinforced areas such as Beam-Column joints, Bridge decks, Post/ Pre-stressed concrete structures, and some industries because of their self-consolidation and proceeds more advantages like labor reduction, speed of construction, safe method, structural, ease of erection, and reduces the compaction time. The flexural behaviour of reinforced concrete beams/ slabs was determined for their tensile and ductility characteristics. The tensile behaviour of concrete was developed by embedding reinforcements, the addition of fibers, etc. In the present research, the novelty was brought in SCC by replacing the mono-steel fibers using stainless steel scrap obtained from the lathe waste of industry. For the preparation of greener SCC as a construction material, the cement was replaced by 30% of GGBS for all mixes. Here, the addition of steel fibers used in SCC volume was in the range from 0% to 2% with an increment of 0.5% and was replaced by the stainless steel scrap of constant 0.125% from the industrial lathe waste. SCC’s fresh and mechanical properties were investigated separately for both mono-steel fibers and hybridized fibers with stainless steel scrap. It was inferred that the SCC mix containing steel fibers of 1.5% when replaced by 0.125% of stainless steel scrap in the hybridized formulation of fibers has performed better tensile strength characteristics among other SCC mixes.
Microbial induced calcite precipitation (MICP) is a part and consequence of metabolic activities of many bacterial species with involvement of various pathways in presence of specific organic and/or inorganic moieties present in the surrounding environment. Microbial or Bioconcrete is a sustainable and promising technology based on MICP that not only supports the self-healing of concrete structures but also mitigates the detrimental effects of CO2 emissions on environment from the cement industry. The calcite precipitation inside concrete matrix results in crack healing with an improvement in matrix characteristics. This paper reviews the various mechanisms involved in MICP and highlights the role of MICP in self-healing inside cement matrix. The paper further throws light on designing of microbial concrete and explores the beneficiary effects of MICP on various mechanical and durability properties of cementitious materials. Further, the prospective challenges associated with microbial concrete production and the future aspects have been discussed.
Paul Yohanna, Roland Kufre Etim, Nodebe Inechi Ekene
et al.
Abstract The progressive increase in the rate of production of plastic bottles by the beverage and food industries in Nigeria has increased considerably over time, constituting large volume of waste generations from plastic waste bottles. Also, increasing demand for eco-friendly soil improvement materials and the growing desire to minimize waste generated daily, prompted the need for this study to look into ways to use such wastes and other sustainable materials in soil improvement. This study investigated the potential use of sisal fiber and plastic waste strips as partial replacement for cement to enhance the geotechnical characteristics of lateritic soils. Various laboratory experiments were conducted, encompassing specific gravity determination, grain size distribution, compaction assessment, Atterberg limit, unconfined compressive strength (UCS), and microscopic analysis. Sisal fiber and plastic waste strips were each varied at 0, 0.5, 1.0, 1.5, 2.0 and 2.5% while maintaining a constant 5% cement added to all the mix proportions. Results of investigation revealed an enhancement in plasticity of the soils with both treatment methods. Liquid limit shows a steady drop from 43% in its natural state to 42% and 41% at 1% sisal fiber and 1% plastic strips content respectively, while plasticity index showed a decline from 14.8% in its natural form to 12.69% and 10.8% at 2% sisal fiber and 1% plastic waste strips content respectively. Strength properties of the treated soil increased with increase in admixtures content. Microanalysis of the natural and optimally modified soils showed alteration in the fabric arrangement of the particles of soils. Based on the results of the study, optimally 1–1.5% sisal fiber/5%cement and 1–1.5% plastic waste strips/5%cement meaningfully improved the soil strength and can both be used as sub-base materials for light trafficked roads.
In 2017, the Swedish parliament committed to making the country fossil-free by 2045, prompting an exploration of experiences and perceptions of transition in three cities hosting carbon-intensive industries – steel, cement and petrochemicals, which currently top the list of Sweden’s industrial emitters. From 2019 to 2024, a Swedish–UK research team employed conventional qualitative methods to gather insights from various stakeholders, including industry, municipal actors, and residents, supplemented by arts-based research methods for co-creating data on affective-emotional life in transition towns. This article argues that arts-based research serves as a valuable tool for accounting for and understanding affective-emotional life in frontline transition towns. The arts-based research (ABR) challenges prevailing technocratic and rational frameworks, aligning with ecofeminist Val Plumwood’s call to address the ‘ecological crisis of reason’ that serves to inhibit achieving sustainable futures. The primary value of this article lies in its contribution to the development and refinement of ABR within the context of just transition studies that I argue can help add citizen perspectives and consideration of affective-emotional life to the just transition discourse.
Economic growth, development, planning, Social history and conditions. Social problems. Social reform
The quality of settlement environments surrounding industries is crucial as it reflects the living conditions affected by industrial activities. A study conducted in Tipar Kidul Village aimed to determine the impact of cement industry activities on the settlement environment. The method of this research uses survey within a multistage random sampling survey. The data collection uses interview. The data analysis is simple linear regression with the accuracy testing including validity, reliability, normality, and linearity tests. The research showed that a majority (62%) of the settlement environments conducted in medium-quality conditions. The researched showed industries play a significant role in taking negative impacts on settlements. Industries tend to make settlements uncomfortable to live in due to various activities. Moreover, a significant correlation was observed, indicating a significant influence with a very strong strength that 76.1% between the quality of settlement environments in Tipar Kidul Village and the activities of the cement industry. The cement industry activities impacted to settlement by affecting air pollution, noise from trucks, and machines. Corporate social responsibility program in Tipar Kidul Village included two program, funding program that gave 50.000 rupiah/person and in 2017 cement industry company helped Tipar Kidul Village to reconstruct along Tipar Kidul Village.
Kasare Yogesh, Meshram Sangita, Pusate Samyak
et al.
The increase in waste from industries has resulted in growing concern for the environment. This form of waste is directly deposited on land, leading to contamination. This waste can be effectively used in the production of various building materials. This not only contributes to the reduction of pollution but also provides an economical alternative for sustainable infrastructure. The utilization of various waste materials is being utilized to enable the development of sustainable building resources. The aim of this study is to investigate the utilization of various types of industrial waste, including cupola Slag, fly ash in the fabrication of building blocks. This study examines different combinations of ingredients for producing building blocks with blends of cupola slag (55% to 80%), fly ash (10 % to 30 %), and maintaining a consistent cement content of 10%. This study consists of total 5 possible mix proportions of cupola slag, with fly ash and cement. This study provides comprehensive information about the properties, test conducted and recommended mixtures. An analysis of the physico-mechanical properties of the building blocks was conducted, and it was found that they meet the standards set by the Indian Standards. The findings indicate that the cupola slag-fly ash-cement (CS-70-FA20) is the best combination and has potential to produce sustainable building blocks. A small-scale model house was built from the developed building blocks of best combination.
Ana Caroline da Silva Figueiredo, Fernanda Souza Oliveira, Antonio Renato Bigansolli
et al.
Abstract Finding ways to reuse residue is an alternative not only to reduce its presence in urban and natural environments, but also to reduce costs and consumption of resources by industries. The objective of this paper is to evaluate the properties of concretes made by replacing conventional coarse and fine aggregates with marble residue. Morphological, granulometry, specific gravimetry and crystalline phase analyses were carried out in the aggregates. The composition of the constituents, by mass, was 1:1,2:3 of Portland cement CPIII-32 RS, fine aggregates, and coarse aggregate, respectively, with the addition of 0.4 of water, molded and cured in water. About 25 concrete samples were made, varying the amount of coarse/fine aggregate in the cement mass according to the aggregates proportions of: A= 100% gravel/ 100% sand, B= 100% coarse RRO/ 50% fine RRO + 50% sand, C= 50% coarse RRO + 50% gravel/ 100% fine RRO, and D = 100% coarse RRO/100% fine RRO. The cylindrical samples measuring ∅50 x 100 mm were subjected to water absorption and compressive strength tests, and the results were compared with standards and literature. The water absorption was smaller than 2.5% and the compressive strength values were between 27-33 MPa, close to the resistance of cement used. Composition B presented the best results among the others, indicating the possibility of using the residue from marble for production of concretes for various purposes such as low load paving, sidewalks, blocks, among others. However, for interlocking floors, higher performance cement should be used to achieve the required strength. This type of concrete adds value to the residue and mitigates environmental impacts.
Yamuna Bhagwat, Gopinatha Nayak, Poornachandra Pandit
et al.
AbstractThe durability of the self compacting concrete is one of the prominent areas of concern in recent years since it has become prevalent due to its ease of handling in the construction industries. However, there is a lack of detailed durability study of M-sand self compacting concrete with polypropylene fibres in the literature. In this paper, self compacting concrete made by Portland pozzolana cement with natural sand and M-sand, different percentages of volume fraction (0%, 0.1%, 0.15% and 0.2%) polypropylene fibres with M-sand is thoroughly investigated for fresh properties, hardened properties, drying shrinkage, water absorption, permeability, acid resistance and corrosion crack initiation time. Further, SEM analysis was carried out to know the effect of polypropylene fibre on the concrete microstructure. The results confirmed that the use of M-sand has improved the fresh, hardened and durability properties of the self compacted concrete than natural sand. Also, it is observed that the addition of polypropylene fibres has reduced the fresh properties of self compacted concrete. However, M-sand with 0.15% polypropylene fibres has slightly improved the strength of self compacting concrete, compression strength by 6.97%, split tensile by 8.68% and flexure strength by 3%. Further, it has reduced the drying shrinkage by 40%, water absorption by 30%, water penetration by 33.33%, and increased the chemical resistance, surface crack initiation period than the natural sand self compacting concrete. Finally, this study concludes that M-sand with 0.15% polypropylene fibres improves the durability of self compacting concrete by reducing effect from aggressive environments and in turn contributes to increased corrosion resistance of reinforcements embedded in concrete. Thus, the study supports the use of self compacting concrete with M-sand and optimum amount of polypropylene fibres to achieve required sustainability in terms of strength and durability.
The article shows the results of studies of dry building mixes (DBM), their strength properties, classification, components of DBM, also shows the technological scheme for obtaining polymer cement glue using DBM technology and the dependence of the cohesive strength of polymer cement glue on the duration of mixing of DBM with water. The dependence of the cohesive strength of the polymer cement adhesive (PCA) on the specific surface of the sand, the dependence of the cohesive strength of the PCA on the content of the polymer additive and the dependence of the cohesive strength of the PCA on the content of the catalyst are also shown. As a result, the conducted studies have shown that the maximum strength is achieved with a specific surface area of mineral filler (sand) 2000 cm2 / g, polymer additive –5%, and NaOH catalyst -4%. The article also presents the goals of the technology of using dry mixes, trends determining the development of the mineral building materials industry, rational use and creation of new types of building materials more efficient and cheaper than traditional ones. In addition, the use of local raw materials and waste from various industries in the production of building materials is an important area of resource and energy conservation in the technology of construction production. And of course, dry mixes, in comparison with commercial mortar and concrete compositions, have a number of advantages, such as performing a minimum of finishing technological operations to transfer dry mixes to working condition (sealing with water), saving expensive cement (by 10-15%) due to plasticization and water retention of prepared solutions, stability of dry mix compositions in as a result of the precise dosage of components and their effective mixing, the productivity of builders increased by 20-25%, by improving the plastic properties of the prepared solutions and reducing transport costs by 15%.
Little published data is available to guide engineers in designing calcium sulfoaluminate belite (CSAB) cement mixtures with adequate workability, strength, and durability. This lack of understanding of design factors, especially the effect of varying w/c, represents a significant barrier to widespread CSAB use. In this study hydration, setting time, and strength development of two CSAB cements with w/c from 0.3 – 0.6 were evaluated. CSAB reaction kinetics varied with increased w/c depending on CSAB composition, specifically calcium sulfate content – with higher w/c increasing retardation in higher anhydrite/ye'elimite content cement, but reduced retardation in lower anhydrite/ye'elimite cement. For both cements, greater w/c led to greater total hydration, increased setting times, and reduced compressive strengths in the pastes and mortar samples. Setting time was linked more closely to anhydrite content than w/c, with greater sulfate volumes shortening setting times.
The effects of carbonation on cement-based materials have drawn much attention because of its profound influences on durability performance of concrete structures. Most accelerated carbonation in lab is conducted at RH 50%–70%, which also dries out cement-based materials. The introduced drying action changes pore structure significantly, making the effects of carbonation obscure. To clarify the effects of pure carbonation, water permeability and related micro-structural characteristics are measured on mature mortars, which have been carbonated at water-saturated state. It is found that after carbonation, the porosity of mortars decreases slightly, with finer overall pore structure and lower characteristic pore size. The water permeability also decreases by roughly 40% on average. Based on the pore size distribution curves obtained through the low-field proton nuclear magnetic resonance technique, water permeability is predicted by the Katz-Thompson and Kozeny-Carman theories with satisfactory accuracy. The decrease of water permeability after carbonation agrees well with the reduced characteristic pore length, which quantitatively verifies the observed refinement of nanoscale pore structure due to pure carbonation.
According to EU goals and the Paris Agreement, an urgent need exists for reducing CO<sub>2</sub> emissions while still securing energy supply. Thus, the timely deployment of carbon capture and storage (CCS) is seemingly unavoidable, especially for the cement and steel industries. However, diverse perceptions of CCS among stakeholders such as experts, politicians, and laypeople exist that could hinder the deployment of the technology. Hence, it is worthwhile to recognise these diverse perceptions and their roots. In the studies on risk perceptions, the emphasis has been mostly on the public, as well as factors that influence the public, such as knowledge dissemination and trust. Although these are crucial elements, they are not enough to explain the complexity of risk perceptions. In contrast to the mainstream research, this paper hypothesises that both laypeople and experts are affected by common cultural denominators, therefore, might have similar patterns of risk perceptions. This research suggests a framework that explains the role of societal culture in risk governance, arguing that thrifty, uncertainty avoidant, hierarchical societies tend to have a higher risk perception of CCS. This study is based on a synthesis of the earlier research, an extensive literature review, and an analysis of interviews data.
This article investigates the contribution of global governance to advancing the decarbonization of energy-intensive industries (EIIs – steel, chemicals, cement, aluminium, etc.). It explores to what extent relevant intergovernmental and transnational institutions have exploited the potentials of global governance to address related barriers and challenges, in particular competitiveness concerns, the need to incentivise investments in breakthrough technologies and enhance circularity across global value chains. We find that global governance's high potential to contribute to the decarbonization of EIIs has remained very much underexploited. Few international institutions contribute and there is no clear centre. Existing institutions have especially not delivered a sector-specific signal/vision and consequent international rules. In response, the formation of a central institution and/or subsector-specific initiatives might be considered. We argue that advancing global governance to tap into its considerable but so far underexploited potential ought to be an integral part of any strategy for the decarbonization of EIIs.
Girts Bumanis, Laura Vitola, Liga Stipniece
et al.
The concrete industry is eagerly pursuing the economic advantages of concrete and the improvement of its long-term properties. One of the most effective approaches to improve concrete properties is associated with replacing part of the Portland cement with pozzolanic additives. Although commercial pozzolans like silica fume have proven to be effective, they come at a high cost. Therefore, the modern construction industry is researching pozzolan alternatives. These new pozzolans could come as by-products from different industries, usually accompanied by low-prices, but their efficiency is questionable in most cases. Therefore, fast and reliable evaluation of the materials’ efficiency is necessary. This study aims to summarize techniques adapted for evaluation of pozzolanic materials in a roadmap and do evaluation of waste stream pozzolanic materials. Four characterization directions were considered – chemical and physical analysis (i and ii) and direct and indirect pozzolanic activity test methods (iii and iv). Five commercial or waste stream pozzolanic materials were compared and results evaluated. Industrial by-products (glass E, glass K, metakaolin) are studied as alternative pozzolans and compared to silica fume and fly ash. Selected materials are evaluated using testing methods, such as XRF, FTIR, XRD, micro-granulometry, BET, Frattini test, saturated lime test, strength activity index and alkali–silica reaction tests. The evaluation roadmap for pozzolan quality assessment is proposed. Results indicate that commercial material silica fume can meet the requirements followed by the test procedures given in roadmap. Promising result was obtained for E glass which also passed the quality assessment and showed respectable performance results. Rest of materials failed such an important parameter as alkali content. Besides, it was concluded that only complex dissemination provides a trusted result, as the Frattini test and saturated lime test showed promising results, the results do not always match the results of the strength activity index and alkali–silica reaction.
Materials of engineering and construction. Mechanics of materials
Sedimentation is important in many processes for example in cement, chemical and food industries. Investigation of the sedimentation process of solid bodies showed a phenomenon as settling velocity is not the constant value as it is expected from the analytical deduction; rather it has fluctuating behaviour. Seeking an explanation, detailed two phase hydrodynamic models are developed. In the present work, two-dimensional incompressible flow equation in conservative Euler form is solved numerically on PC by an implicit finite difference method, and the fluid-solid interaction is described by the Immersed Boundary Method. For additional model validation, Particle Tracing module of COMSOL is applied as well. The self-developed simulator based on an a priori (white box) model, and the 3D model by the commercial CFD software is used for modelling the two-phase system and the particle motion in the fluid column. Settling velocity is calculated and compared to the velocity of a particle recorded by a high-speed camera measurement system in the laboratory scale sedimentation equipment. The results are promising, and after improvements, the simulator can be a useful tool in supporting energetically optimal industrial design and operation.
Chemical engineering, Computer engineering. Computer hardware