燃煤烟气胺法脱碳MVR再生系统关键参数及能耗分析

针对燃烧后胺法脱碳工艺再生能耗高的问题，本文将机械蒸汽再压缩（mechanical vapor recompression，MVR）节能技术与胺法再生工艺集成，建立燃煤烟气胺法脱碳MVR再生系统。采用速率基非平衡模型，以再生能耗为目标函数，对影响再生系统能耗的关键工艺参数进行考察，分析其对MVR再生系统的影响规律。结果表明，MVR技术在燃煤烟气胺法脱碳再生系统中表现出良好的节能效果，但最终节能效率应低于41.3%；在0.35～0.55mol/mol范围内增加富液CO₂担载量以及从90℃到115℃提升进塔温度，再生能耗快速降低；增加再生塔压力，MVR再生系统的再生能耗亦呈下降趋势，再生塔压力控制在2atm以下较为合适；降低闪蒸压力，压缩机能耗不断增加，再沸器能耗快速降低，闪蒸压力的合理取值区间为0.9～1.0atm；降低塔顶冷凝器温度从70℃到20℃，再生能耗略微增加，CO₂气体纯度提高。

Key parameters and energy consumption analysis of amine decarburization regeneration system with MVR for coal-fired flue gas

For the problem of high energy consumption for regeneration of post-combustion amine decarburization process, an amine decarburization regeneration system with MVR (mechanical vapor recompression）was established through integrating MVR technology into the ammonia regeneration process. Taking the regenerative energy consumption as the objective function, the key parameters affecting the energy consumption were investigated based on a rate-based non-equilibrium model, and their influence law on the regeneration system were analyzed. Results showed that MVR technology shows good energy saving effect in this regeneration system, but the energy-saving efficiency should be lower than 41.3%. With the increasing of the rich liquid loading in the range of 0.35—0.55mol/mol and raising the feed temperature from 90℃ to 115℃, the energy consumption of regeneration were reduced quickly. Although increasing the pressure of the regeneration tower contribute to reduce the regenerative energy consumption, it was more suitable to control the pressure below 2atm. Reducing the pressure of the flash tower, the compressor duty was constantly increased, the reboiler duty was reduced quickly. The reasonable range of flash pressure is 0.9—1.0 atm. Reducing condenser temperature from 70℃ to 20℃ slightly increase regeneration energy consumption and improve CO₂ purity.