Article
Construction & Building Technology
Rotana Hay, Abdullah Khalil, Cornelius Otchere, Sara Alanis, Kemal Celik
Summary: This study assessed the influence of PCE-based superplasticizers on the hydration and carbonation kinetics of reactive magnesium oxide (MgO) cement. Highly workable RMC-based composites were achieved with the addition of superplasticizers and fibers, and a higher compressive strength was obtained under carbonation conditions. The PE fibers provided crack control mechanism, and the finalized mix was successfully applied for the construction of a large-scale architectural structure.
JOURNAL OF MATERIALS IN CIVIL ENGINEERING
(2023)
Article
Construction & Building Technology
Fengshun Wu, Xujia You, Mingming Wang, Tiejun Liu, Bao Lu, Guihua Hou, Ruiyu Jiang, Caijun Shi
Summary: This study examines the impact of Mg(OH)(2) on the in-situ formation of fibre-like aragonite and the mechanical properties of cement mortar subjected to accelerated carbonation. The addition of Mg(OH)(2) has a limited effect on the compressive strength but significantly improves the flexural strength of the carbonated samples. FTIR and XRD analysis confirm that aragonite, rather than calcite, becomes the dominant CaCO3 polymorph with more than 5% Mg(OH)(2) content. The in-situ formed fiber/needle-like aragonite increases the total porosity and refines the pore sizes of carbonated samples when Mg(OH)(2) is added.
CEMENT & CONCRETE COMPOSITES
(2023)
Article
Construction & Building Technology
Maciej Zajac, Jorgen Skibsted, Barbara Lothenbach, Frank Bullerjahn, Jan Skocek, Mohsen Ben Haha
Summary: This study investigates the impact of alkali sulfates on CO2 mineralization process using alkaline waste materials. The results show that sulfates are important phases influencing the mineralization, and the interaction between alkalis and sulfate ions can control the kinetics and extent of carbonation. Additionally, sulfate-containing materials can now be considered for CO2 sequestration.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
R. Hay, N. T. Dung, A. Lesimple, C. Unluer, K. Celik
Summary: This study found that the compressive strength of concrete samples cured under ambient conditions increased when exposed to high temperatures, while the accelerated formation of brucite enhanced the compressive strength of carbonated samples. A relatively stable compressive strength was observed for the carbonated samples at temperatures ranging between 100 and 300 degrees C.
CEMENT & CONCRETE COMPOSITES
(2021)
Article
Environmental Sciences
Can Cheng, Wenjun Huang, Haomiao Xu, Zhisong Liu, Xianwei Li, Hongzhi Shi, Yongmei Yu, Zan Qu, Naiqiang Yan
Summary: The steel smelting process generates large amounts of CO2 and Ca-containing steel slag (SS), which leads to the waste of Ca resources due to the low value utilization of SS. This study proposes an innovative two-step leaching and carbonation method for efficient leaching, carbon sequestration, and high-value reuse of SS. The method significantly increases the leaching rate of activated Ca and achieves a high CO2 sequestration capacity. This work presents a strategy with potential for recycling SS and reducing carbon emissions.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Construction & Building Technology
Rotana Hay, Bo Peng, Kemal Celik
Summary: This study explored the impact of different CaCO3 polymorphs from limestone and seashell on the hydration and carbonation kinetics of reactive MgO cement (RMC). The results showed that the limestone powder had superior filler effects, enhancing the early stage of hydration and increasing the compressive strength under air curing. The nucleation effect of limestone did not promote more brucite formation but involved the creation of amorphous phases, which encapsulated and passivated the MgO substrate, thereby restricting its hydration. Under carbonation, nucleation induced by both CaCO3 forms improved the composite strengths by producing carbonation products of larger morphologies, resulting in pore filling and matrix densification. Amorphous phases with hydromagnesite-like and fused structures were observed.
CEMENT AND CONCRETE RESEARCH
(2023)
Article
Geosciences, Multidisciplinary
Rui Guo, Jiaoyue Wang, Longfei Bing, Dan Tong, Philippe Ciais, Steven J. Davis, Robbie M. Andrew, Fengming Xi, Zhu Liu
Summary: Because of the alkaline nature and high calcium content of cements, they can serve as a CO2-absorbing agent and reduce emissions during production. A life-cycle assessment is necessary to determine the actual net carbon impacts of the cement industry. Mortar is estimated to be the greatest contributor to the total carbon uptake among four types of cement materials.
EARTH SYSTEM SCIENCE DATA
(2021)
Article
Construction & Building Technology
Peiliang Shen, Jianxin Lu, Yangyang Zhang, Yi Jiang, Shipeng Zhang, Chi Sun Poon
Summary: This study developed an innovative wet carbonation process to prepare aragonite whisker-rich materials and used them as micro-fiber additions to cement. The results showed that needle-like aragonite whiskers could be rapidly synthesized under specific conditions, and a new type of micro-fiber reinforced cement was developed by mixing them with cement.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Zhen Li, Zhichao Zhang, Jihui Qin, Yanfei Yue, Jueshi Qian
Summary: This paper studies the effects of introducing nesquehonite seeds on the performance of reactive magnesia cement (RMC). It shows that nesquehonite seeds can facilitate the hydration of RMC, resulting in reduced setting times and increased nesquehonite formation and carbonation degree. Additionally, nesquehonite seeds combined with hydration agent can promote the compressive strength and CO2 sequestration capacity of RMC.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Chemistry, Physical
Young-Jin Kim, Sang-Rak Sim, Dong-Woo Ryu
Summary: This study developed a technology to reduce CO2 emissions and utilize CO2 from the cement industry by replacing cement with CO2 reactive hardening cement. The results showed that as the content of CO2 reactive hardening cement increased, the carbonation depth, compressive strength increase rate, and CO2 sequestration rate increased, indicating that it can be used as a secondary cement product.
Article
Construction & Building Technology
Zhen Li, Ying Hua, Zixun Chang, Yanfei Yue, Jihui Qin, Jueshi Qian
Summary: This study investigated the effect of lime addition on the performance and CO2 sequestration capacity of blended reactive MgO cement (RMC). The results showed that the incorporation of lime promoted the setting and initial heat generation of RMC, and increased its CO2 absorption capability. Carbonation curing improved the strength and microstructure of the blended RMC by reducing porosity and increasing density. Samples with 20% lime content had significantly higher compressive strength compared to plain samples.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Construction & Building Technology
Yisong Liu, Zhi-Yuan Zhang, Yang Zheng, Xiaozhu Zhang, Xiaofei Wang, Xianghui Yin
Summary: This study compared the physical properties, mechanism, and environmental impact of reactive MgO cement (RMC) and MOS cement. The results showed that the strength of RMC increased while that of MOS decreased. Carbon footprint analysis indicated that RMC cement had advantages in carbon emissions.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Construction & Building Technology
Geetika Mishra, Panagiotis Danoglidis, Surendra P. Shah, Maria Konsta-Gdoutos
Summary: The novelty of this study is to find the optimal amount of biochar and high calcium fly ash to improve mechanical performance and CO2 uptake in cement mortar. The potential of biochar-fly ash mixes was optimized using response surface methodology (RSM) while considering the influence of different amounts of fly ash (FA), biochar (B), and their interactions. The experimental results indicate that the combination of biochar and high calcium fly ash enhances both the mechanical properties and CO2 sequestration in cement mortar.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Review
Construction & Building Technology
Dianchao Wang, Jianzhuang Xiao, Zhenhua Duan
Summary: In the past twenty years, significant researches have been conducted on the accelerating fixation technologies of carbon dioxide through the carbonation reaction of cement-based materials. This study reviews the literature on the application of carbonation of cement-based materials for carbon dioxide sequestration, discussing the impact of carbonation on the physical and mechanical behavior of recycled aggregates and concrete, efficiency improvement methods, and acceleration methods on the mechanical behavior of cement-based materials. Results show that carbonation can effectively improve the mechanical performance of recycled aggregates and concrete, and parameters such as liquid water content, sample size, environmental pressure, carbon dioxide concentration, and temperature significantly affect the sequestration efficiency of carbon dioxide of cement-based materials. Proposals for future application of fast carbon dioxide sequestration technologies in industrial areas and cement-based material recycling have been put forward.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Review
Green & Sustainable Science & Technology
Chikezie Chimere Onyekwena, Qiang Xue, Qi Li, Happiness Ijeoma Umeobi, Abdul Ghaffar, Mohammad Hamed Fasihnikoutalab
Summary: This article aims to review previous studies on the reaction mechanisms of rMgO, factors influencing the carbonation curing of rMgO-based composites, and the application of carbonated rMgO in soil stabilization. The findings suggest that rMgO hydration is crucial and material properties and curing conditions affect the carbonation process. Carbonation treatment improves the mechanical and durability performance of carbonated rMgO composites by refining the pore structure and improving porosity. Utilizing hydration agents eliminates delayed hydration and enhances carbonation efficiency. Recommendations for future research directions on rMgO-based composites carbonation are provided.
CLEAN TECHNOLOGIES AND ENVIRONMENTAL POLICY
(2023)
Article
Construction & Building Technology
N. T. Dung, R. Hay, A. Lesimple, K. Celik, C. Unluer
Summary: This study found that the microstructural and mechanical properties of reactive MgO cement concrete are enhanced as the CO2 concentration increases. 5-20% CO2 led to a 5-fold increase in compressive strength, but samples cured under 20% CO2 showed limitations on further CO2 diffusion. The use of 5% CO2 produced comparable strengths at 28 days as 20% CO2, while samples cured under 10% CO2 exhibited the best performance.
CEMENT & CONCRETE COMPOSITES
(2021)
Article
Construction & Building Technology
R. Hay, N. T. Dung, A. Lesimple, C. Unluer, K. Celik
Summary: This study found that the compressive strength of concrete samples cured under ambient conditions increased when exposed to high temperatures, while the accelerated formation of brucite enhanced the compressive strength of carbonated samples. A relatively stable compressive strength was observed for the carbonated samples at temperatures ranging between 100 and 300 degrees C.
CEMENT & CONCRETE COMPOSITES
(2021)
Article
Construction & Building Technology
Rotana Hay, Jiaqi Li, Kemal Celik
Summary: The study found that Portland cement forms a large amount of highly polymerized silica gels during carbonation, achieving a high carbonation content. CaCO3 polymorphs dominate, and the carbonated material exhibits improved micromechanical properties.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Inderjeet Singh, Rotana Hay, Kemal Celik
Summary: The study investigated the direct carbonation of brucite recovered from reject brine and observed significant improvement in mechanical properties post-carbonation. Findings suggest that cost-effective synthesis of brucite from reject brine could sequester CO2, making it a promising material for the construction industry.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Abdullah Khalil, Sungmin Sohn, Kemal Celik
Summary: The research demonstrates that RMC-based paste samples gain strength after exposure to temperatures as high as 300 degrees C, regardless of whether they were cured in ambient conditions or under accelerated carbonation. The specific heat of the samples increases while thermal conductivity and thermal diffusivity decrease with increasing temperature, indicating that RMC has excellent strength retention at high temperatures.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Rotana Hay, Liang Li, Kemal Celik
Summary: This study investigated the effect of different levels of hemihydrate sulfation on the autogenous shrinkage of limestone calcined clay cement (LC3) based mixes. The results showed that optimal mechanical performance could be achieved at a specific sulfation level. The study also revealed the coupling effect of physicochemical and microstructural changes on autogenous shrinkage and the performance of LC3-based concrete composites.
CEMENT & CONCRETE COMPOSITES
(2022)
Review
Construction & Building Technology
Nouran Elmesalami, Kemal Celik
Summary: Bendable concrete is a special type of high-performance concrete with significant environmental impacts due to its high OPC content. Geopolymer is considered a promising alternative to fully replace OPC in ECCs. Research on Engineered Geopolymer Composites (EGCs) is ongoing and further exploration is needed to realize their full potential.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Rotana Hay, Bo Peng, Kemal Celik
Summary: This study explored the impact of different CaCO3 polymorphs from limestone and seashell on the hydration and carbonation kinetics of reactive MgO cement (RMC). The results showed that the limestone powder had superior filler effects, enhancing the early stage of hydration and increasing the compressive strength under air curing. The nucleation effect of limestone did not promote more brucite formation but involved the creation of amorphous phases, which encapsulated and passivated the MgO substrate, thereby restricting its hydration. Under carbonation, nucleation induced by both CaCO3 forms improved the composite strengths by producing carbonation products of larger morphologies, resulting in pore filling and matrix densification. Amorphous phases with hydromagnesite-like and fused structures were observed.
CEMENT AND CONCRETE RESEARCH
(2023)
Article
Green & Sustainable Science & Technology
Farah Shahbaz, Inderjeet Singh, Padmaja Krishnan, Kemal Celik
Summary: This study conducted a life cycle assessment to evaluate the environmental impact of brucite and synthetic magnesium oxide recovered from reject brine in the UAE. The production processes of synthetic Mg(OH)2 and MgO were quantified using various alkali sources. The results showed that brucite recovered from reject brine had lower environmental impact and could serve as a promising magnesium-based binder.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Construction & Building Technology
Rotana Hay, Abdullah Khalil, Cornelius Otchere, Sara Alanis, Kemal Celik
Summary: This study assessed the influence of PCE-based superplasticizers on the hydration and carbonation kinetics of reactive magnesium oxide (MgO) cement. Highly workable RMC-based composites were achieved with the addition of superplasticizers and fibers, and a higher compressive strength was obtained under carbonation conditions. The PE fibers provided crack control mechanism, and the finalized mix was successfully applied for the construction of a large-scale architectural structure.
JOURNAL OF MATERIALS IN CIVIL ENGINEERING
(2023)
Article
Construction & Building Technology
Xiangyu Wang, Abdullah Khalil, Kemal Celik
Summary: Recent research has focused on incorporating supplementary materials like cenospheres in cement matrix to reduce construction costs and carbon footprint while maintaining durability. This study found that the addition of cenospheres improved paste extrudability and retained good buildability, paving the way for developing 3D-printable WPC-based mixtures with improved structural and thermal properties for modern construction needs.
ACI MATERIALS JOURNAL
(2021)
Article
Green & Sustainable Science & Technology
Lars odegaard Bentsen, Narada Dilp Warakagoda, Roy Stenbro, Paal Engelstad
Summary: This study investigates uncertainty modeling in wind power forecasting using different parametric and non-parametric methods. Johnson's SU distribution is found to outperform Gaussian distributions in predicting wind power. This research contributes to the literature by introducing Johnson's SU distribution as a candidate for probabilistic wind forecasting.
JOURNAL OF CLEANER PRODUCTION
(2024)
Article
Green & Sustainable Science & Technology
Xing Liu, Qiuchen Wang, Yunhao Wen, Long Li, Xinfang Zhang, Yi Wang
Summary: This study analyzes the characteristics of process parameters in three lean gas ethane recovery processes and establishes a prediction and multiobjective optimization model for ethane recovery and system energy consumption. A new method for comparing ethane recovery processes for lean gas is proposed, and the addition of extra coolers improves the ethane recovery. The support vector regression model based on grey wolf optimization demonstrates the highest prediction accuracy, and the multiobjective multiverse optimization algorithm shows the best optimization performance and diversity in the solutions.
JOURNAL OF CLEANER PRODUCTION
(2024)
Article
Green & Sustainable Science & Technology
Cairong Song, Haidong Yang, Xian-Bing Meng, Pan Yang, Jianyang Cai, Hao Bao, Kangkang Xu
Summary: The paper proposes a novel deep learning-based prediction framework, aTCN-LSTM, for accurate cooling load predictions. The framework utilizes a gate-controlled multi-head temporal convolutional network and a sparse probabilistic self-attention mechanism with a bidirectional long short-term memory network to capture both temporal and long-term dependencies in the cooling load sequences. Experimental results demonstrate the effectiveness and superiority of the proposed method, which can serve as an effective guide for HVAC chiller scheduling and demand management initiatives.
JOURNAL OF CLEANER PRODUCTION
(2024)
Article
Green & Sustainable Science & Technology
Zhe Chen, Xiaojing Li, Xianli Xia, Jizhou Zhang
Summary: This study uses survey data from the Loess Plateau in China to evaluate the impact of social interaction on the adoption of soil and water conservation (SWC) technology by farmers. The study finds that social interaction increases the likelihood of farmers adopting SWC, and internet use moderates this effect. The positive impact of social interaction on SWC adoption is more pronounced for farmers in larger villages and those who join cooperative societies.
JOURNAL OF CLEANER PRODUCTION
(2024)
Article
Green & Sustainable Science & Technology
Chenghua Zhang, Yunfei Yan, Kaiming Shen, Zongguo Xue, Jingxiang You, Yonghong Wu, Ziqiang He
Summary: This paper reports a novel method that significantly improves combustion performance, including heat transfer enhancement under steady-state conditions and adaptive stable flame regulation under velocity sudden increase.
JOURNAL OF CLEANER PRODUCTION
(2024)
