燃烧后化学吸收技术是现阶段最成熟的燃煤电厂烟气CO2捕集技术之一。由于传统的胺基吸收剂再生能耗较高，不利于化学吸收碳捕集技术的推广应用。液-液两相吸收剂能大幅降低再生能耗，具备替代传统吸收剂的前景。综述了两相吸收剂的技术特点和研发进展，根据吸收剂组成将两相吸收剂分成混合胺型两相吸收剂（活性胺+三级胺分相剂+水）、有机溶剂型两相吸收剂（活性胺+有机溶剂分相剂+水）和无水型两相吸收剂（活性胺+三级胺/有机溶剂分相剂）3种类型，重点对这3种类型两相吸收剂的分相行为、能耗、黏度、吸收负荷等特性进行分析。其中有机溶剂型两相吸收剂在能耗（1.5～3.2 GJ/t）、黏度（可控制在20 mPa·s以下）和成本（有机溶剂分相剂+水更具成本潜力）等方面优势相对更明显。两相吸收剂作为新型吸收剂，相比传统胺吸收剂在工业应用方面仍存在富相黏度较高、吸收剂成本较高、分相稳定控制难等较多挑战。为加快两相吸收剂的工程应用，未来需要在低能耗配方体系优化、降低富相黏度和吸收剂损耗、提升分相控制能力以及开展长周期运行测试，提升工艺稳定和可靠性等方面开展更深入研究。

Post-combustion chemical absorption is one of the most mature technologies for CO2 capture from coal-fired power plants. However, the high energy consumption for regeneration of traditional amine-based solvents is not conducive to the commercial application of chemical absorption technology. Liquid-liquid biphasic solvents, which can greatly reduce the regeneration energy consumption, have the prospect of replacing traditional solvents. The technical characteristics and solvents development of liquid-liquid biphasic solvents were reviewed in this paper. The liquid-liquid biphasic solvents can be divided into three types according to the composition, namely blending amine type (active amine + tertiary amine phase separation agent + water), organic solvent type (active amine + organic solvent phase separation agent + water) and water-free type (active amine + tertiary amine/organic solvent phase separation agent). The analysis focused on the phase separation behavior, energy consumption, viscosity and CO2 absorption load of three different type biphasic solvents. Among them, organic solvent type biphasic solvents have more advantages in regeneration energy consumption (1.5-3.2 GJ/t), viscosity (can be controlled below 20 mPa·s), and cost (organic solvent phase separation agent + water shows better potential in cost). As a new type of solvent, liquid-liquid biphasic solvents still face many challenges in industrial application compared to traditional solvents, such as high viscosity of rich phase, high cost of solvents and difficult in phase separation control, etc. In order to accelerate the industrial application of biphasic solvents, it is necessary to carry out more in-depth research on optimizing the formula system with low energy consumption, reducing the rich phase viscosity and the loss of solvents, improving the phase separation control ability and carry out long cycle operation tests to improve process stability and reliability.

0 引言

1 两相吸收剂特点与工艺

2 两相吸收剂特性

   2.1 混合胺型两相吸收剂

   2.2 有机溶剂型两相吸收剂

   2.3 无水型两相吸收剂

3 工业应用挑战

   3.1 再生能耗

   3.2 黏度

   3.3 吸收分相

   3.4 吸收剂损耗

   3.5 工业试验

4 结语及展望