Assesssment of pozzolanic/hydraulic reactivity of vitreous calcium aluminosilicate (VCAS) ussing different methods

[EN] The aim of this paper is to assess the possibility of using vitreous calcium aluminosilicate (VCAS) as a supplementary cementitious material in the production of Portland cement mortars. The calcium hydroxide consumption by VCAS is assessed by two different methods: firstly, a classical method based on thermogravimetric analysis (TGA) and, secondly, pH and electrical conductivity measurements of calcium hydroxide/VCAS suspensions with excess calcium hydroxide. Evidence of pozzolanic reactivity of VCAS is revealed in hydrated lime pastes, and low reactivity was observed in aqueous suspensions. The reactivity of VCAS is also assessed by means of TGA of VCAS/ OPC pastes and by means of the mechanical strength development of Portland cement mortars, with VCAS replacement percentages in the range of 10 30%. The results obtained show that pozzolanic and hydraulic reactions take place in OPC systems. VCAS can be used as a supplementary cementitious material by replacing OPC at levels of 10 30% by mass.The authors are grateful to the Spanish Ministry of Science and Innovation for supporting this study through Project GEOCEDEM BIA 2011-26947, and to FEDER funding.Mitsuuchi Tashima, M.; Soriano Martínez, L.; Paya Bernabeu, JJ.; Monzó Balbuena, JM.; Borrachero Rosado, MV. (2016). Assesssment of pozzolanic/hydraulic reactivity of vitreous calcium aluminosilicate (VCAS) ussing different methods. Materials and Design. 96:424-430. https://doi.org/10.1016/j.matdes.2016.02.036S4244309

Industria del cemento: ¿cuál sería el efecto de los impuestos a sus emisiones de carbono?

Este producto forma parte de una serie de infografías de divulgación científica que buscan reseñar algunas de las investigaciones más importantes en las que ha tenido participación la Universidad EAFIT, publicadas en las revistas especializadas más prestigiosas del mund

Product level embodied carbon flows in bilateral trade

As increasingly complex modelling approaches to quantifying embodied carbon in trade have become popular, the lack of disaggregation has been identified as a key weakness. This paper quantifies embodied carbon in bilateral trade at the product level. This is done using the material balance approach, by collecting product carbon intensity factors from multiple data sources and combining with bilateral trade data in physical quantities. The dataset covers trades between 195 countries for 1080 products in 2006. The detailed mapping of trade embodied carbon provides detailed insights into the nature of the flows that were previously masked or under-reported. For example, it finds that the lion's share of global trade embodied emissions are concentrated in a relatively small number of product categories of traded goods, suggesting that focusing mitigation efforts and trade-measures on these products would be an effective strategy to address potential carbon leakage, and to decarbonise international supply chains. The results also highlight that embodied carbon is focused in regional trade, thus regional harmonisation of climate mitigation policy will be effective in mitigating leakage