While carbon capture and utilization (CCU) technology often face economic challenges, CCU via carbon mineralization with solid waste offers a cost-effective solution. In this work, the feasibility of a proposed CCU process that utilizes captured CO2 from the accelerated weathering of limestone (AWL) process to mineralize cement kiln dust (CKD) to produce a green brick termed CKD-bicarbonate lime brick (CKD-BLB) was evaluated with techno-economic analysis (TEA). The main variable that affects the techno-economic feasibility of the proposed CCU process is the absorber size, as it dictates the amount of captured CO2 and producible CKD-BLB. This variable also indirectly impacts the environmental aspect, as different absorber sizes contribute to varying degrees of CO2 avoidable. Thus, this work conducts a multi-objective stochastic optimization to determine the optimal absorber size with consideration of profitability and CO2 avoidance. It was found that the optimal absorber size of 67. 93 m3 achieved a maximum NPV of 3, 165. 38 million with a desirable CO2 avoidance of 21, 337. 41 MT₂₎₂. Although increasing the absorber size to 93. 96 m3 would increase the process’s avoidable CO2 by 2. 87%, the 3. 22% drop in its NPV result is a less favorable tradeoff between the two aspects. A sensitive analysis was also conducted, and the results indicate that among CKD-BLB price, electricity cost and water cost, the CKD-BLB price is the most sensitive parameter affecting the NPV of the proposed process. A ± 50% variation in CKD-BLB price leads to more than a 100% shift in NPV, while at a ± 50% variation in electricity and water costs results in less than a 30% change. Overall, the insights generated in this work enable strategic planning for decisions making.
Chai et al. (Mon,) studied this question.