天然气深冷工艺装置提高乙烷收率工艺技术的研究与应用

Research and application of improving ethane recovery rate approaches in natural gas cryogenic unit

目的针对天然气深冷工艺装置中因原料气气量下降、气质变贫造成C_(2)^(+)轻烃收率下降、装置运行难度大等导致装置乙烷收率降低的问题,采用调配较富原料气气源、原料气中补充丙烷和原料气中补充丁烷等措施开展提高装置乙烷收率的工艺技术研究。方法基于建立的工艺模型,对比核算原料气中补充丙烷和丁烷对提高乙烷产量的影响,考查分析原料气中补充丙烷和丁烷对改善脱甲烷塔运行状况的效果。结果经现场验证得出,通过调配榆济线优质气源和补充丙烷等措施可有效提高装置乙烷收率,乙烷产品年产量可增加1438.54 t,乙烷收率由62%提高至70%。结论该工艺的应用不仅可以获得经济效益256.88万元/年,而且具有较大的推广价值。

Objective Aiming at the problems of decreasing natural gas capacity and poor gas composition resulting in low C_(2)^(+) hydrocarbon recovery rate and difficult operation in natural gas cryogenic unit,approaches of scheduling rich natural gas resources,increasing propane and butane into feed gas are adopted to improve ethane recovery rate.Base on the process model,the effects of increasing propane and butane into feed gas on improving ethane production and operation conditions of the demethanizer were compared and investigated respectively.Results After the application of these high efficient process in the natural gas cryogenic unit and field test,the annual ethane production has already increased 1438.54 tons,ethane recovery rate has also improved from 62%to 70%.Conclusions The implementation of this measure can not only obtain economic benefits of CNY 2568880 per year,but also has a good prospect of promotion and application.