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• Accelerated carbonation and biological conversion offers low operation cost. • Accelerated carbonation can valorise industrial waste for CCU operation. • CCU in construction-related industries possesses tremendous grown potential. The construction industry is one of the largest CO 2 emitters worldwide. This review outlines all existing CO 2 capture technologies in the construction-related industry which are mainly found in the cement, steel, iron and construction material production industry. This review found that carbon capture and utilization (CCU) is the preferred alternative for carbon capture in the construction-related industry due to its ability to produce value-added products. Among the CCU pathways, alternatives that capture CO 2 via carbon mineralization have received the most attention due to their capabilities to valorize industrial waste to produce carbonate products. Unlike the production of liquid CO 2 , hydrogen, purified CO 2 and biofuels from the majority of the carbon capture system (excluding hydroxide absorption and accelerated carbonation system), carbonate products can be directly utilized for construction application, reducing costs associated with product transportation. Although CCU technologies have potential sustainable carbon-capturing processes, outlined barriers such as high operating cost, low CO 2 capture capabilities and low maturity hinder their commercialization. To overcome these limitations, continuous development is crucial. Recommendations for the development of CCU technologies such as the creation of standards for carbonate products, incorporation of promoters or hybrid mixing, integration of IR 4.0' principles and process intensification into existing CCU technologies are deliberately discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

The accelerated weathering of limestone (AWL) process is an inexpensive and eco-friendly carbon dioxide (CO 2) capture process with comparable performance to amine-based systems. However, the generated calcium bicarbonate (Ca(HCO 3) 2) solution lacks an effective utilization alternative. Aside from that, the current solid waste utilization alternatives (i.e., carbon mineralization and partial replacement of conventional binders) lack the capability to effectively curb the tremendous production rate of solid waste (i.e., cement kiln dust (CKD)). To address both gaps, this study developed a novel Ca(HCO 3) 2 solution utilization alternative with CKD as the sole binder to produce a building material termed CKD-bicarbonate lime mortar (BLM). This work aims to identify the optimal mix ratio for CKD-BLM to achieve maximum compressive strength via a series of studies; (i) liquid medium, (ii) Ca(HCO 3) 2 solution volume, and (iii) sand:CKD mix ratio. From the findings, it was found that CKD-BLM at the optimal CKD:sand:Ca(HCO 3) 2 mix ratio of 1:0.45:0.29 exhibits the highest compressive strength of 2.09 MPa, surpassing the compressive strength standard of 1.70 MPa set by the ASTM C141 while having acceptable workability of 118 % which is within the standard workability range of 105–155 % set by ASTM C270. However, the CKD-BLM sample exhibits high leaching of Ca, Si, Na and Cl which does not meet the environmental regulation. This was resolved by applying a waterproof coating that effectively curbed the leaching by 28.84–99 %. Overall, this study successfully developed a building material with industrial wastes (i.e., Ca(HCO 3) 2 solution and CKD) that surpasses the performance of conventional lime mortar while utilizing up to 0.22 kg CO 2.kg CKD-BLM_1:0.45:0.29−1. [Display omitted] • Cement kiln dust is used as feedstock for bicarbonate mortar production. • CKD-BLM_1:0.45:0.29 was able to achieve a strength of 2.09 MPa. • Generated CKD-BLM are able to meet ASTM standard requirements. • Able to achieve a CO 2 storage capacity of 0.22 kg CO 2.kg CKD-BLM. • Encapsulation with waterproof coating can curb heavy metals leaching up to 99.17 %. [ABSTRACT FROM AUTHOR]