Assessment of CO2 reduction of alkali-activated concrete

Although alkali-activated (AA) concrete is generally regarded as one of the most effective concrete technologies for reducing CO2 emissions, very few investigations have been carried out on the assessment of the CO2 reduction of such concrete. The present paper reports an evaluation procedure for th...

Full description

Saved in:

Bibliographic Details
Published in:	Journal of cleaner production 2013-01, Vol.39, p.265-272
Main Authors:	Yang, Keun-Hyeok, Song, Jin-Kyu, Song, Keum-Il
Format:	Article
Language:	eng
Subjects:	Alkali-activated concrete Animal, plant and microbial ecology Applied ecology Applied sciences Assessments Binder intensity Binders Biological and medical sciences Buildings. Public works Carbon dioxide Cements CO2 intensity Concretes Concretes. Mortars. Grouts Conservation, protection and management of environment and wildlife Environment and sustainable development Exact sciences and technology Fundamental and applied biological sciences. Psychology General aspects GGBS LCI database Materials Precast concrete products Process control Reduction
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	Although alkali-activated (AA) concrete is generally regarded as one of the most effective concrete technologies for reducing CO2 emissions, very few investigations have been carried out on the assessment of the CO2 reduction of such concrete. The present paper reports an evaluation procedure for the CO2 reduction of AA concrete. The studied system considers all of the steps from the cradle to pre-construction. CO2 reduction for secondary precast concrete products is also evaluated with reference to practical examples wherein ground granulated blast-furnace slag (GGBS) cement is replaced with AA GGBS binder. Comparisons of the performance efficiency indicators, binder and CO2 intensities, reveal that the contribution of the binder to the total CO2 emission is more significant in ordinary Portland cement (OPC)-based concrete than in AA concrete, whereas the contribution of aggregate transportation becomes more critical in AA concrete than in OPC-based concrete. The reduction rate of CO2 emission of AA concrete relative to OPC concrete commonly ranges between 55 and 75%. In addition, the CO2 reduction rate in secondary precast concrete products that use AA GGBS binder instead of GGBS cement can be evaluated as approximately 20% when the total aggregate-to-binder ratio ranges between 3.0 and 4.0. On the other hand, Ca(OH)2-based AA GGBS concrete shows a CO2 intensity that is approximately 2.4 times lower than that of OPC concrete. Overall, the slope of the increasing rate of the CO2 intensity against the binder intensity is lower in Ca(OH)2-based AA GGBS concrete than in OPC-based concrete. ► This study assesses the life-cycle CO2 reduction of alkali-activated (AA) concrete. ► We ascertain the global warming impact of AA concrete using performance indicators. ► This study shows that AA binder is a key approach for producing sustainable concrete.
ISSN:	0959-6526 1879-1786