砜胺体系吸收有机硫的热力学及动力学探讨

Thermodynamics and kinetics of organic sulfur absorption in sulfolane-amine system

关键词:  有机硫脱除  砜胺  天然气净化  GB 17820-2018  热力学  动力学  计算模型

Key words:  organic sulfur removal  sulfolane-amine  natural gas purification  GB 17820-2018  thermodynamics  kinetics  calculation model

摘要:

砜胺法作为脱除天然气中有机硫最常用的工艺,在国内外取得了较为广泛的应用。然而目前对于这一工艺的机理研究仍较为缺乏,动力学及热力学基础数据缺失,导致难以准确预测其工业应用效果。针对这一问题,对砜胺体系的室内实验和现场应用数据进行了分析,从反应机理、气液平衡、传质动力学等方面,研究了影响有机硫在该体系吸收的因素。并尝试将这些因素关联为计算模型,通过实验数据的回归得到砜胺溶剂的速率因子和亨利系数。该模型可用于物理-化学溶剂脱除有机硫工艺的运行参数和塔设备参数估算,其对MDEA和砜胺溶剂的模拟计算结果与实际运行规律相符,可为天然气中总硫含量达标(GB 17820-2018《天然气》)改造工作提供理论支撑。 

Abstract:

As the most commonly used process to remove organic sulfur from natural gas, sulfolane-amine process has been widely used at home and abroad. However, there is still a lack of mechanism research and basic data of kinetics and thermodynamics, which makes it difficult to accurately predict the industrial application results. Aiming at this problem, laboratory experiment and field application data of sulfolane-amine system were analyzed, and the factors influencing the absorption of organic sulfur in the system were studied from the aspects of reaction mechanism, gas-liquid equilibrium and mass transfer kinetics. Calculation model was established by correlating these factors, in which the rate factor and Henry coefficient of sulfolane-amine solvent were obtained from the regression of experimental data. The model can be used to estimate the operation parameters and absorb tower parameters of the organic sulfide removal process using physical-chemical solvent, and its simulation results for MDEA and sulfolane-amine are consistent with the actual operation, which can provide a theoretical support for the transformation project with the total sulfur contents in natural gas to meet the requirement of GB 17820-2018 Natural Gas.