Work

Optimizing Al2O3 Ceramic Membrane Heat Exchangers for Enhanced Waste Heat Recovery in MEA-Based CO2 Capture

Year: 2026

Type: article

Abstract: High regeneration energy demand remains a critical barrier to the large-scale deployment of ethanolamine-based (MEA-based) CO2 capture. This study adopts an Al2O3 ceramic-membrane heat exchanger (CMHE) to recover both sensible and latent heat from the stripped gas. Experiments confirm that heat and mass transfer within the CMHE follow a coupled mechanism in which capillary condensation governs trans-membrane water transport, while heat conduction through the ceramic membrane dominates heat transfer, which accounts for more than 80%. Guided by this mechanism, systematic structural optimization was conducted. Alumina was identified as the optimal heat exchanger material due to its combined porosity, thermal conductivity, and corrosion resistance. Among the tested pore sizes, CMHE-4 produces the strongest capillary-condensation enhancement, yielding a heat recovery flux (q value) of up to 38.8 MJ/(m2 h), which is 4.3% and 304% higher than those of the stainless steel heat exchanger and plastic heat exchanger, respectively. In addition, Length-dependent analyses reveal an inherent trade-off: shorter modules achieved higher q (e.g., 14–42% greater for 200-mm vs. 300-mm CMHE-4), whereas longer modules provide greater total recovered heat (Q). Scale-up experiments demonstrated pronounced non-linear performance amplification, with a 4 times area increase boosting q by only 1.26 times under constant pressure. The techno-economic assessment indicates a simple payback period of ~2.5 months and a significant reduction in net capture cost. Overall, this work establishes key design parameters, validates the governing transport mechanism, and provides a practical, economically grounded framework for implementing high-efficiency CMHEs in MEA-based CO2 capture.

Source: Membranes

DOI: 10.3390/membranes16010043

Authors: Qiufang Cui, Ziyan Ke, Jinman Zhu, Shuai Liu, Shuiping Yan

Institutions: NingboTech University, Huazhong Agricultural University

Language: English

Topic: Carbon Dioxide Capture Technologies

Subfield: Mechanical Engineering

Field: Engineering

Domain: Physical Sciences

SDGs: Affordable and clean energy, Responsible consumption and production, Climate action

Open Access status: gold

Estimated APC paid: $2,654