Abstract:

The rectisol process for capturing CO₂ requires low-temperature environment, a significant amount of freezing energy, and considerable energy consumption. Introducing nanoparticles into absorbents can effectively enhance the gas-liquid mass transfer rate and reduce energy consumption. This study aimed to develop methanol-based nanofluids with reduced cooling demand and improved absorption and desorption performance. The effects of factors such as the type of nanoparticles, solid loading, particle size, surfactant content, temperature, and initial CO₂ concentration on CO₂ capture performance were investigated, and the impact mechanisms were studied. The results indicated that the CO₂ absorption and desorption enhancement effect of TiO₂-methanol nanofluid with a concentration of 0.4g/L was the best among TiO₂, Al₂O₃ and SiO₂ nanofluids with concentrations ranging from 0.2—1.0g/L. After adding 0.10% polyethylene glycol octylphenyl ether (Triton X-100), the absorption and desorption enhancement effect of the nanofluid were the highest, and it still showed a noteworthy enhancement effect after 5 cycles. Furthermore, this article provided an in-depth analysis of the mechanism of enhanced absorption of nanofluids and proposed an empirical formula to predict the enhancement factor E and optimal solid loading of TiO₂-methanol nanofluids.

Key words: carbon dioxide capture, bubble reactor, model, nanofluids, low cooling demand, enhanced mass transfer

摘要：

冷甲醇洗法捕集CO₂技术要求低温环境，需要大量的冷冻能量，能耗较大。在吸收剂中引入纳米颗粒，可以有效提高气液传质速率，降低能耗。本研究旨在开发冷量需求少，吸收、解吸性能提升的甲醇基纳米流体。实验分别考察了纳米颗粒种类、固含量、尺寸，表面活性剂含量、操作温度和初始CO₂浓度等因素对吸收剂捕集CO₂性能的影响及机理。结果表明，在0.2~1.0g/L的TiO₂、Al₂O₃、SiO₂纳米流体中，0.4g/L的TiO₂-甲醇纳米流体的CO₂吸收、解吸增强效果最佳。向其中添加0.10%（质量分数）聚乙二醇辛基苯基醚（Triton X-100）后，纳米流体的吸收、解吸增强效果达到最大，且在5次循环后仍呈现良好增强效果。此外，本文对纳米流体增强吸收的机理进行了深入分析，提出了一个经验公式来预测TiO₂-甲醇纳米流体的增强因子E和最佳固含量。

关键词: 二氧化碳捕集, 鼓泡反应器, 模型, 纳米流体, 低冷量供给, 传质增强