Process Intensification of CO₂ Desorption

Abstract

Anthropogenic climate change due to, among other causes, unhindered CO 2 emissions is a major concern worldwide. The postcombustion capture (PCC) process using a solvent, known as chemical absorption, is currently the most effective way to reduce CO 2 emissions from large point sources. However, high capital investment costs when using the conventional packed bed absorber/desorber technology and high energy requirements during solvent regeneration are the primary obstacles for its large-scale implementation. Different process intensification (PI) technologies to desorb CO 2 from the solvent have been introduced to mitigate the energy consumption compared to the conventional packed bed technology. This work reviews different technologies for intensification of CO 2 desorption. In this context, rotating packed beds, microreactors, and membrane contactors have been explored as potential alternatives to intensify the desorption because of their superior mass and heat transfer. Alternative energy sources like ultrasound and microwaves have also been used to improve the desorption performance of conventional equipments. PI can also be realized by using novel solvents with improved desorption kinetics in combination with intensification equipment. Thus in this review, a comprehensive assessment of different existing PI technologies based on regeneration energies and regeneration efficiencies relative to conventional technology is presented. The intensification of mass transfer for the different technologies is compared, and a new parameter, named the regeneration factor, is proposed to evaluate the performance of PI equipment. This study outlines the advances in process intensification of CO 2 desorption technologies to date and presents an overview of the merits and limits of all technologies.

Big Data Analysis and Technical Review of Regeneration for Carbon Capture Processes

“…Performance of different technologies to intensify the desorption of CO 2 from solvents: PB, packed bed; i-PB, intensified packed bed; RPB, rotating packed bed; MW, microwave regeneration; US, ultrasound-assisted regeneration; MR, microreactor; MS, membrane stripping; CA, catalyst-aided solvent regeneration. Reproduced with permission from ref . Copyright 2022 American Chemical Society.…”

“…Figure shows the array of key technologies explored for CO 2 desorption intensification . Although the authors found that microreactors and membrane contactors are the most promising routes due to the enhanced CO 2 mass transfer coefficient that they provide, one critical drawback of these is their difficult scalability.…”

“…Historic and current CO 2 capture remediation studies disproportionately focused heavily on developing/reviewing sorbent and solvent formulations for/with improved CO 2 adsorption capacity, adsorption kinetics, and cycling − compared with improving different facets of the CO 2 regeneration process . Importantly, some reviews in the last 10 years generally described CO 2 regeneration of CaO-based and Rectisol- or other solvent-based processes, , and even thoroughly detailed the intensification of CO 2 desorption in solvent-based processes in an attempt to bring these sparse studies to the attention of the research community. , Some review articles published in Energy & Fuels focused on the regeneration schemes of solvents used in hollow fiber membrane contactors, process intensification technologies for CO 2 mass transfer during desorption from solvent systems (discussed later), and recent progress in adsorption-based CO 2 capture technology, with a minor focus on common CO 2 desorption methods . Still, there exists a need to assemble and summarize the detailed desorption process characteristics of the various dominant CO 2 mitigation technologies in one collection.…”

“…Applicable to both aqueous and nonaqueous solvent systems, Gecim et al presented a comprehensive review on the different technologies to intensify the desorption of CO 2 from solvents relative to the standard packed bed reactor configuration typically used. 30 The authors clarify that intensification refers to technologies that both enhance gas− liquid mass and heat transfer and reduce equipment size and energy requirement.…”

“…Figure 16 shows the array of key technologies explored for CO 2 desorption intensification. 30 Although the authors found that microreactors and membrane contactors are the most promising routes due to the enhanced CO 2 mass transfer coefficient that they provide, one critical drawback of these is their difficult scalability. Given the rapid advancements in rotating packed bed systems relative to the other technologies, this route is the most promising for industrial application.…”