海南福山油田天然气脱汞技术

NATURAL GAS HYDRAGYRUM (Hg) REJECTING TECHNIQUE IN FUSHAN OILFIELD OF HAINAN PROVINCE

大多数天然气的主要成分是气体烃类,此外也含少量非烃类气体,个别天然气中还含有微量的惰性气体(如氦、氩),甚至含有极微量的元素汞等,我国海南福山油田个别天然气中就含有元素汞。尽管其含量极微,但它仍有可能引起天然气凝液回收等装置中板翅式换热器的腐蚀泄漏,危害极大,故必须脱除。为此,介绍了该油田的天然气脱汞技术:在预处理系统中增加了脱汞塔,采用浸渍硫的活性炭脱除其中的汞,经分子筛干燥器脱水后的气体进入脱汞塔顶部脱汞。2007年3月脱汞装置投入运行后效果良好,脱汞后的气体中检测不出汞含量。

In spite of hydrocarbon gases as main contents, most natural gases contain a small amount of non-hydrocarbon gases; while some natural gases contain a slight volume of rare gases, like helium (He), argon (Ar), etc., some even contain minor hydragyrum (Hg), such as the natural gas found in Fushan Oilfield of Hainan Province. Because very little Hg contained in the gas there will result in corrosion and leakage of tilted plate heat exchanger used in condensate liquids recovering devices, it is still necessary to reject Hg from the gas. Therefore, this paper introduced this technology of rejecting Hg from natural gas in this oil field, i.e., a Hg-rejecting tower was added in the previous pre-treating system, inside this tower active carbon with soaked sulfur was used to extract Hg at the first step, and then the dehydrated gas from molecular flow desiccator would feed into the top of this tower to get rid of Hg completely. This technology has been proved to be good since being started to be put into production in March of 2007, and the important of all, even the slight content of Hg could not be detected after being rejected from the gas in this way.