天然气三甘醇脱水工艺的技术进展

Technical progress of TEG dehydration process in natural gas industry

关键词:  天然气  TEG  脱水  Drizo工艺  惰气气提  水露点  水含量 

Key words:  natural gas  TEG  dehydration  Drizo process  inert gas stripping  water dew point  water content

摘要:

对天然气开发过程重要配套工艺之一的原料气三甘醇(TEG)脱水的技术发展动向进行了讨论。目前,应用最广泛的贫TEG提浓措施为惰气气提,该措施可将贫TEG质量分数提高至99.20%~99.98%,相应的露点降范围为55~83 ℃。经改进的Drizo工艺可使干气中水的质量分数降至1×10-6以下,脱水深度达到分子筛吸附脱水的水平。该工艺还具有减少BTEX/CO₂排放、可回收原料气所含芳烃、降低投资与成本等技术经济优势,尤其适用于FLNG工程。同时,近年来在国外建设的TEG脱水装置上,高效规整填料、电动齿轮泵、能量转换泵和全焊式板式换热器等新型设备及材料的应用日益普及。 

Abstract:

TEG dehydration is an important technology for natural gas exploitation. The developmental tendencies of TEG dehydration process were discussed in this article. Recently inert gas stripping is the most popular measure to concentrate TEG and can improve the purity of TEG to 99.20%-99.98% which correspond to the water dew point depression range of 55-83 ℃ for dry gas. The improved Drizo process can reduce the mass concentration of water to lower than 1×10-6, the dehydration efficiency may reach that of molecular sieve adsorption process. The TEG dehydration process can reduce BTEX/CO₂ emission and recover aromatic, which will decrease CAPEX and OPEX also. Especially, Drizo process is suitable for FLNG engineering. At present brand-new equipments and materials are increasingly utilized in TEG dehydration unit, such as high-efficiency structured packing, electric gear pump, energy exchange pump and welded plate heat exchanger etc..