天然气中硫醇的深度脱硫溶剂研发与工业应用  

Research&development and evaluation a of deep mercaptan removal solvent in natural gas

作　　者：杨超越 常宏岗 薛靖文 范锐 叶辉[4] 朱雯钊 YANG Chaoyue;CHANG Honggang;XUE Jingwen;FAN Rui;YE Hui;ZHU Wenzhao(Research Institute of Natural Gas Technology,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610213,China;National Energy R&D Center of High Sulfur Gas Exploitation,Chengdu,Sichuan 610213,China;Gas Field Development Management Department,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610051,China;Northwest Sichuan Division,PetroChina Southwest Oil&Gasfield Company,Jiangyou,Sichuan 621700,China)

机构地区：[1]中国石油西南油气田公司天然气研究院 [2]国家能源高含硫气藏开采研发中心 [3]中国石油西南油气田公司气田开发管理部 [4]中国石油西南油气田公司川西北气矿

出　　处：《天然气工业》2023年第3期123-132,共10页Natural Gas Industry

摘　　要：GB 17820—2018《天然气》实施后,原料气气质中有机硫含量较高(大于20 mg/m^(3))的净化厂采用了有机硫脱除技术,以满足标准中一类气的指标要求。但从国内外有机硫脱除技术的应用情况来看,对于RSH含量高(大于30 mg/m^(3))的原料气,还存在对硫醇脱除率不高的问题,产品气总硫有超标的风险。为此,基于理论计算,开展了RSH脱除机理研究,揭示了硫醇与砜胺溶剂体系的反应机理,通过改善脱硫溶剂中关键组分的亲核性来提升溶剂对硫醇的化学吸收,研发出了一种新型的硫醇深度脱除溶剂。研究结果表明:(1)通过对醇胺分子结构改进,自主合成了分子结构中N原子具有强亲核性的新组分,形成了硫醇深度脱除溶剂,可促进其对硫醇的离解,提高硫醇脱除率。(2)在实验室条件下考察了不同压力、不同气液比条件下硫醇深度脱除溶剂的性能,压力低至1.5MPa,该溶剂对硫醇脱除率大于90%;气液比高达1200时,该溶剂对硫醇脱除率大95%。(3)在天然气净化厂工业应用中,在原料气硫醇含量超过300 mg/m^(3)的条件下,经硫醇深度脱除溶剂净化后,产品气总硫低于5 mg/m^(3),硫醇脱除率超过99%。结论认为,该技术可应用于硫醇含量高的天然气净化处理,技术的推广应用对我国天然气气质升级以及天然气长输管道的安全平稳运行具有重要意义。After the implementation of"Natural Gas"GB 17820-2018,purification plants whose feed gas has higher organic sulfur content(>20 mg/m^(3))adopt the organic sulfur removal technology to meet the index requirements of the first-class gas in the standard.However,the application situations of organic sulfur removal technologies at home and abroad show that the feed gas with high RSH content(>30 mg/m^(3))still suffers low mercaptan removal efficiency,and the product gas faces the risk that the total sulfur is not qualified.Based on theoretical calculation,this paper researches the RSH removal mechanisms,and reveals the reaction mechanisms between mercaptan and sulfolane-amine solvent system.In addition,the chemical absorption of solvent to mercaptan is improved by modifying the nucleophilicity of the key components in desulfurization solvent,and thus a new type of deep mercaptan removal solvent is developed.And the following research results are obtained.First,a new component whose N atom has strong nucleophilicity in the molecular structure is synthesized independently by modifying the molecular structure of hydramine,so deep mercaptan removal solvent is developed,which can promote the dissociation of mercaptan,so as to increase the mercaptan removal efficiency.Second,in the laboratory,the performance of the deep mercaptan removal solvent is evaluated under different pressures and gas/liquid ratios.When the pressure is as low as 1.5 MPa,the mercaptan removal efficiency is over 90%.When the gas/liquid ratio is up to 1200,the mercaptan removal efficiency is more than 95%.Third,in the industrial application of natural gas purification plant,the total sulfur of the product gas is lower than 5 mg/m^(3) and the mercaptan removal efficiency is higher than 99%after the feed gas with mercaptan content over 300 mg/m^(3) is purified with deep mercaptan removal solvent.In conclusion,this technology is applicable to the purification of the natural gas with high mercaptan content,and its popularization and application is of great si

关 键 词：天然气 净化厂 有机硫 硫醇 GB 17820—2018 气质升级 脱硫 总硫 

分 类 号：TE644[石油与天然气工程—油气加工工程]