天然气深冷处理装置分子筛脱水工艺分析与研究

Research on Molecular Sieve Dehydration Process in NG Cryogenic Separation Unit

简述了天然气工业脱水的几种方法以及脱水在天然气处理中的重要性,介绍了大港油田天然气公司分子筛脱水工艺流程,对两塔及三塔分子筛脱水工艺进行了对比,提出新装置必选四塔工艺的必要性。分析了影响分子筛脱水效果及分子筛使用寿命的关键因素,提出了分子筛吸附温度、吸附周期、充泄压速率、再生气流量及性质、再生气温度及原料气洁净度控制要点,对分子筛脱水系统中的节能要点进行了简要归纳。总结了分子筛吸附温度的合理精细化控制对分子筛使用寿命、深冷装置产量的影响,提出在不同分子筛使用阶段要及时调整合理的吸附周期。

The article introduces briefly the essential dehydration processes in natural gas industry, with focus on the molecular sieve dehydration processes in Dagang Oilfield Company. Through research on the molecular sieve dehydration processes with two-tower and three-tower, it puts forward a four-tower process for the new unit. It also analyzes the key factors affecting the molecular sieve dehydration and service life, and identifies the controlling points such as molecular sieve adsorption temperature, adsorption cycle, venting pressure rate, gas flow and properties, gas temperature and gas feedstock cleanliness, as well as energy saving in the process. Finally it summarizes the effects of finely controlling the adsorption temperature on molecular sieve service life and on cryogenic unit yield, and the necessity of promptly adjusting the reasonable adsorption cycle in different molecular sieve using stage.