{"title":"预蒸压处理对碳化镁渣体积稳定性和抗压强度的影响","authors":"Xin Xu, Jinhui Liu, Yuandong Mu, Yixin Zhang, Yuming Zhao, Peixu Yang, Weidong Zhang, Xiaofeng Li, Yong Hu, Weineng Tang, Jiajia Tian, Zhongtao Luo, Shaojun Zhang","doi":"10.1016/j.jma.2024.12.016","DOIUrl":null,"url":null,"abstract":"The primary magnesium production is accompanied by a large amount of magnesium slag (MS) discharge. The low hydration reactivity of γ-Ca<sub>2</sub>SiO<sub>4</sub> (γ-C<sub>2</sub>S) and MgO in MS results in the volume stability issue and low utilization rate of MS. To eliminate the issue, this study proposes to pre-autoclave the MS slurry to boost the hydration of γ-C<sub>2</sub>S and MgO and then utilize their hydration products to prepare cementitious materials by carbonation curing. MgO from MS and prepared γ-C<sub>2</sub>S are firstly employed as study objects respectively, for they are the main contents of magnesium slag. The results indicate that pre-autoclaving treatment can strongly elevate the hydration degree of MgO from MS, this can substantially solve the volume stability issue of MS. Meanwhile, the pre-autoclaving of γ-C<sub>2</sub>S induces the generation of crystallized and amorphous C-S-H products, and both products could promote the carbonation reaction when compared to γ-C<sub>2</sub>S. The carbonation degree of pre-autoclaved MS firstly increases and then decreases with the rising pre-autoclaving temperature, and the optimal pre-autoclaving temperature for MS carbonation is 160 °C, at this time, the powdered MS can be simply carbonated fully. The sample made of pre-autoclaved MS and then subjected to 4 h carbonation could achieve the compressive strength of 29 MPa. with good soundness. During volume stability testing, the volume expansion rate of a carbonated MS sample with pre-autoclaving was 0.07 %, which is significantly lower than the normal requirement of 0.5 %. This research offers a novel approach to utilizing magnesium slag in building materials and contributes to carbon reduction.","PeriodicalId":16214,"journal":{"name":"Journal of Magnesium and Alloys","volume":"1 1","pages":""},"PeriodicalIF":15.8000,"publicationDate":"2025-01-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Effect of pre-autoclaving treatment on volume stability and compressive strength of carbonated magnesium slag\",\"authors\":\"Xin Xu, Jinhui Liu, Yuandong Mu, Yixin Zhang, Yuming Zhao, Peixu Yang, Weidong Zhang, Xiaofeng Li, Yong Hu, Weineng Tang, Jiajia Tian, Zhongtao Luo, Shaojun Zhang\",\"doi\":\"10.1016/j.jma.2024.12.016\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"The primary magnesium production is accompanied by a large amount of magnesium slag (MS) discharge. The low hydration reactivity of γ-Ca<sub>2</sub>SiO<sub>4</sub> (γ-C<sub>2</sub>S) and MgO in MS results in the volume stability issue and low utilization rate of MS. To eliminate the issue, this study proposes to pre-autoclave the MS slurry to boost the hydration of γ-C<sub>2</sub>S and MgO and then utilize their hydration products to prepare cementitious materials by carbonation curing. MgO from MS and prepared γ-C<sub>2</sub>S are firstly employed as study objects respectively, for they are the main contents of magnesium slag. The results indicate that pre-autoclaving treatment can strongly elevate the hydration degree of MgO from MS, this can substantially solve the volume stability issue of MS. Meanwhile, the pre-autoclaving of γ-C<sub>2</sub>S induces the generation of crystallized and amorphous C-S-H products, and both products could promote the carbonation reaction when compared to γ-C<sub>2</sub>S. The carbonation degree of pre-autoclaved MS firstly increases and then decreases with the rising pre-autoclaving temperature, and the optimal pre-autoclaving temperature for MS carbonation is 160 °C, at this time, the powdered MS can be simply carbonated fully. The sample made of pre-autoclaved MS and then subjected to 4 h carbonation could achieve the compressive strength of 29 MPa. with good soundness. During volume stability testing, the volume expansion rate of a carbonated MS sample with pre-autoclaving was 0.07 %, which is significantly lower than the normal requirement of 0.5 %. This research offers a novel approach to utilizing magnesium slag in building materials and contributes to carbon reduction.\",\"PeriodicalId\":16214,\"journal\":{\"name\":\"Journal of Magnesium and Alloys\",\"volume\":\"1 1\",\"pages\":\"\"},\"PeriodicalIF\":15.8000,\"publicationDate\":\"2025-01-04\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Magnesium and Alloys\",\"FirstCategoryId\":\"88\",\"ListUrlMain\":\"https://doi.org/10.1016/j.jma.2024.12.016\",\"RegionNum\":1,\"RegionCategory\":\"材料科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"METALLURGY & METALLURGICAL ENGINEERING\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Magnesium and Alloys","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1016/j.jma.2024.12.016","RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"METALLURGY & METALLURGICAL ENGINEERING","Score":null,"Total":0}
Effect of pre-autoclaving treatment on volume stability and compressive strength of carbonated magnesium slag
The primary magnesium production is accompanied by a large amount of magnesium slag (MS) discharge. The low hydration reactivity of γ-Ca2SiO4 (γ-C2S) and MgO in MS results in the volume stability issue and low utilization rate of MS. To eliminate the issue, this study proposes to pre-autoclave the MS slurry to boost the hydration of γ-C2S and MgO and then utilize their hydration products to prepare cementitious materials by carbonation curing. MgO from MS and prepared γ-C2S are firstly employed as study objects respectively, for they are the main contents of magnesium slag. The results indicate that pre-autoclaving treatment can strongly elevate the hydration degree of MgO from MS, this can substantially solve the volume stability issue of MS. Meanwhile, the pre-autoclaving of γ-C2S induces the generation of crystallized and amorphous C-S-H products, and both products could promote the carbonation reaction when compared to γ-C2S. The carbonation degree of pre-autoclaved MS firstly increases and then decreases with the rising pre-autoclaving temperature, and the optimal pre-autoclaving temperature for MS carbonation is 160 °C, at this time, the powdered MS can be simply carbonated fully. The sample made of pre-autoclaved MS and then subjected to 4 h carbonation could achieve the compressive strength of 29 MPa. with good soundness. During volume stability testing, the volume expansion rate of a carbonated MS sample with pre-autoclaving was 0.07 %, which is significantly lower than the normal requirement of 0.5 %. This research offers a novel approach to utilizing magnesium slag in building materials and contributes to carbon reduction.
期刊介绍:
The Journal of Magnesium and Alloys serves as a global platform for both theoretical and experimental studies in magnesium science and engineering. It welcomes submissions investigating various scientific and engineering factors impacting the metallurgy, processing, microstructure, properties, and applications of magnesium and alloys. The journal covers all aspects of magnesium and alloy research, including raw materials, alloy casting, extrusion and deformation, corrosion and surface treatment, joining and machining, simulation and modeling, microstructure evolution and mechanical properties, new alloy development, magnesium-based composites, bio-materials and energy materials, applications, and recycling.