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Vietnam is the world’s largest cement exporter. In 2022, it produced 118 Mtpa cement while emitting 109 Mtpa cement-related CO2, equal to 33% of Vietnam’s total CO2 emission. As Vietnam has pledged to achieve net zero by 2050, unabated cement-related CO2 emission must be drastically reduced in the future. This paper investigates the contribution of carbon capture and storage (CCS) to decarbonizing Vietnam’s cement industry to make cement production cleaner and more sustainable. A first-of-a-kind CO2 source-sink mapping exercise was conducted to map 68 cement plants to subsurface sinks, including oil and gas reservoirs and saline aquifers, using four CCS field development concepts. The results have identified four first-mover CCS projects where CO2 emissions from 27 cement plants are mapped to nearby offshore subsurface CO2 sinks. Two of these projects are located in Vietnam-north, one in Vietnam-central, and one in Vietnam-south. In the Vietnam-south CCS project, CO2 emission from the Kien Giang province is transported and stored in the offshore Block B gas field. In the other three CCS projects, CO2 emission is transported to nearshore saline aquifers in the Song Hong Basin. At a CO2 capture rate of 90%, these four projects will mitigate 50 Mtpa CO2, which is 46% of cement-related CO2 emission or 15% of total CO2 emission from Vietnam, thus making Vietnam’s cement production cleaner and more sustainable. Future research should focus on subsurface characterization of saline aquifers in the Song Hong Basin. The methodology developed in this study is usable in other cement-producing countries with significant CO2 sinks in the nearshore continental shelf.

There is an increasing global recognition of the need for environmental sustainability in mitigating the adverse impacts of cement production. Despite the implementation of various carbon dioxide (CO2) mitigation strategies in the cement industry, such as waste heat recovery, the use of alternative raw materials and alternative fuels, energy efficiency improvements, and carbon capture and storage, overall emissions have still increased due to the higher production levels. The resolution of this matter can be efficiently achieved by the substitution of traditional materials with an alternative material, such as calcined clay (CC), construction and demolition waste (CDW), which have a significant impact on various areas of sustainable development, including environmental, economic, and social considerations. The primary objectives of employing CDW in the Portland cement production are twofold: firstly, to mitigate the release of CO2 into the atmosphere, as it is a significant contributor to environmental pollution and climate change; and secondly, to optimize the utilization of waste materials, thereby addressing the challenges associated with their disposal. The purpose of this work is to present a thorough examination of the existing body of literature pertaining to the partial replacement of traditional raw materials by CDW and the partial replacement of Portland cement by CDW and to analyze the resulting impact on CO2 emissions.

Purpose – Cement production has advanced greatly in the last few decades. The traditional fuels used in traditional kilns include coal, oil, petroleum coke, and natural gas. Energy costs and environmental concerns have encouraged cement companies worldwide to evaluate to what extent conventional fuels can be replaced by waste materials, such as waste oils, mixtures of non-recycled plastics and paper, used tires, biomass wastes, and even wastewater sludge. The paper aims to discuss these issues. Design/methodology/approach – The work is based on literature review. Findings – The clinker firing process is well suited for various alternative fuels (AF); the goal is to optimize process control and alternative fuel consumption while maintaining clinker product quality. The potential is enormous since the global cement industry produces about 3.5 billion tons that consume nearly 350 million tons of coal-equivalent fossil and AF. This study has shown that several cement plants have replaced part of the fossil fuel used by AF, such waste recovered fuels. Many years of industrial experience have shown that the use of wastes as AF by cement plants is both ecologically and economically justified. Originality/value – The substitution of fossil fuels by AF in the production of cement clinker is of great importance both for cement producers and for society because it conserves fossil fuel reserves and, in the case of biogenic wastes, reduces greenhouse gas emissions. In addition, the use of AF can help to reduce the costs of cement production.

Refuse-derived fuel (RDF) from municipal solid waste (MSW) is an alternative fuel (AF) partially replacing coal/petcoke in a calciner/kiln of cement plant. The maximum thermal substitution rate (TSR) achieved through RDF is 80–100% in the calciner, while it is limited to 50–60% in the kiln burner. Different AF pre-combustion technologies, advancements in multi-channel burners, and new satellite burners have supported high TSR. Extensive efforts in modelling kiln burner and calciner lead to enhance TSR. However, the cement industry faces operational issues such as incomplete combustion, increased specific heat consumption, reduced flame temperature, and kiln coating buildup. There is an interest in RDF gasification, a promising alternative to eliminate the operational issues of the cement industry, which needs to be integrated with the existing cement plant. The article reviews the integration of gasification in cement production and various experimental and modelling studies of the direct firing of AF/RDF in the kiln/calciner. The features and technology status of both approaches are compared. The different gasification integration technologies with varied configurations for cement plant calciner are highlighted. The article emphasizes the need to develop suitable calciner/kiln-gasifier models for predicting calciner output based on different RDFs. Graphical Abstract

Cement is one of the most produced materials globally. Population growth and urbanization cause an increased demand for the cement needed for expanding infrastructures. As a result of this circumstance, the cement industry must find the optimum compromise between increasing cement production and reducing the negative environmental impact of that production. Since cement production uses a lot of energy, resources and raw materials, it is essential to assess its environmental impact and determine methods for the sector to move forward in sustainable ways. This paper uses an integrated life cycle assessment (LCA) and a system dynamics (SDs) model to predict the long-term environmental impact and future dynamics of cement production in South Africa. The first step used the LCA midpoint method to investigate the environmental impact of 1 kg of Portland cement produced in South Africa. In the cement production process, carbon dioxide (CO2), nitrogen oxides (NOx), sulphur dioxide (SO2), methane (CH4) and particulate matter (PM) were the major gases emitted. Therefore, the LCA concentrated on the impact of these pollutants on global warming potential (GWP), ozone formation, human health, fine particulate matter formation and terrestrial acidification. The system dynamics model is used to predict the dynamics of cement production in South Africa. The LCA translates its results into input variables into a system dynamics model to predict the long-term environmental impact of cement production in South Africa. From our projections, the pollutant outputs of cement production in South Africa will each approximately double by the year 2040 with the associated long-term impact of an increase in global warming. These results are an important guide for South Africa’s future cement production and environmental impact because it is essential that regulations for cement production are maintained to achieve long-term environmental impact goals. The proposed LCA–SD model methodology used here enables us to predict the future dynamics of cement production and its long-term environmental impact, which is the primary research objective. Using these results, a number of policy changes are suggested for reducing emissions, such as introducing more eco-blended cement productions, carbon budgets and carbon tax.

This study aimed to investigate the environmental impact of modified granulated copper slag (MGCS) utilization in blended cement production at a representative cement plant in China. Sensitivity analysis was performed on the substance inputs, and the life cycle impact assessment (LCIA) model was applied. A detailed comparative analysis was conducted of the environmental impact of cement production in other studies, and ordinary Portland cement production at the same cement plant. Results showed that calcination has the largest contribution impact of all the impact categories, especially in causing global warming (93.67%), which was the most prominent impact category. The life cycle assessment (LCA) result of blended cement was sensitive to the chosen LCIA model and the depletion of limestone and energy. In this study, producing blended cement with MGCS effectively mitigated the environmental impact for all the selected impact categories. Results also show a reduction in abiotic depletion (46.50%) and a slight growth (6.52%) in human toxicity. The adoption of MGCS in blended cement would therefore generally decrease the comprehensive environmental impact of cement, which contributes to the development of sustainable building materials.

The rapid growth of industrialisation and urbanisation has significantly increased the demand for construction materials such as concrete, and consequently, for portland cement. However, in regions like Europe, where ambitious climate targets have been established, the cement industry is under increasing pressure to decarbonise while continuing to meet the rising demand. Although a wide range of decarbonisation strategies have been explored in the literature, their adoption remains challenging in isolated or geographically constrained regions. This study presents a life cycle assessment (LCA) to evaluate the environmental impacts of cement production in isolated regions such as Malta, Iceland, Fiji, and Mauritius, in comparison with European and global averages. The system boundary is defined as “cradle-to-gate,” including raw material extraction, local and international transportation, and manufacturing stages, with a functional unit defined as 1 tonne of cement imported to the isolated region. The LCA was conducted using Activity Browser v2.8, focusing on climate change impact using the IPCC 2021 method. This analysis identifies key environmental hotspots within the cement supply chain and examines the influence of transportation in isolated regions. This study seeks to better identify practical decarbonisation solutions that account for regional constraints such as local resource availability and infrastructural limitations, promoting a more resilient and self-sufficient supply chain that can meet national demands while aligning with broader climate goals.

The study focuses on the nonlinear Granger causality between cement production, economic growth and carbon dioxide emissions by Markov-switching vector autoregressive (MScVAR) and Markov-switching Granger causality approach for the period of 1960–2017 for China and the USA. The empirical findings from MSIA(2)-VAR(2) for the USA and MSIA(3)-VAR(3) for China suggest that cement production has an important impact on CO2 emissions and economic growth. Markov-switching causality approach determines the evidence of unidirectional causality running from cement production to carbon dioxide emissions in all regimes for the USA and China. The cement production is an important source of environmental pollution. The USA and China have global responsibility for cement production determined as one of the central sources of carbon dioxide emissions. Moreover, MS-Granger causality results were compared with ones determined by traditional causality method. It was determined that to employ traditional method instead of MS-causality method can cause wrong policy applications if the tested series has nonlinearity.Graphical abstract

Cement production is a carbon-intensive process that contributes significantly to global greenhouse gas emissions. Approximately 50–60% of these emissions result from limestone calcination, while 30–40% result from fossil fuel combustion in kilns. This study presents a multi-objective optimization (MOO) framework that integrates raw mix design and alternative fuel blending to simultaneously reduce production costs and carbon dioxide (CO2) emissions while maintaining clinker quality. A hybrid Genetic Algorithm–Linear Programming (GA-LP) model was developed to navigate the balance between economic and environmental objectives under stringent chemical and operational constraints. The approach models the impact of raw materials and fuel ash on critical clinker quality indices: the Lime Saturation Factor (LSF), Silica Modulus (SM), and Alumina Modulus (AM). It incorporates practical constraints such as maximum substitution rates and specific fuel compositions. A case study inspired by a medium-sized African cement plant demonstrates the utility of the model. The results reveal a Pareto front of optimal solutions, highlighting that a 20% reduction in CO2 emissions from 928 to 740 kg/ton clinker is achievable with only a 24% cost increase. Optimal strategies include 10% fly ash and 30–50% alternative fuels, such as biomass, tire-derived fuel (TDF), and dynamic raw mix adjustments based on fuel ash contributions. Sensitivity analysis further illustrates how biomass cost and LSF targets affect clinker performance, emissions, and fuel shares. The GA-LP hybrid model is validated through process simulation and benchmarked against African case studies. Overall, the findings provide cement producers and policymakers with a robust decision-support tool to evaluate and adopt sustainable production strategies aligned with net-zero targets and emerging carbon regulations.

Cement production is one of the most important industries on the planet, and humans have relied on is use dating back to the dawn of civilization. Cement manufacturing has increased at an exponential rate, reaching 3 billion metric tons in 2015, representing a 6.3% annual growth rate and accounting for around 5–8% of global carbon dioxide (CO2) emissions. Geopolymer materials, which are inorganic polymers made from a wide range of aluminosilicate powders, such as metakaolin, fly ash, and blast furnace or steel slags, have also been elicited for use due to concerns about the high energy consumption and CO2 emissions connected with cement and concrete manufacturing. This study focused on the mechanical and durability properties of metakaolin in concrete production. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) analyses were used to confirm the characteristics of kaolin and metakaolin. The results showed that 15 wt.% metakaolin can be used to partially replace cement, and that metakaolin, when synthesized with alkaline activators, can also be utilized as a geopolymer to totally replace cement in concrete production. For predicting the compressive strength of different concrete mixtures, few practical models have been presented. This research has shed light on the possibility of utilizing ecologically friendly materials in the building, construction, and transportation sectors to decrease carbon dioxide emissions.