油气田行业作业场所空气中甲烷的六通阀气体进样-毛细管柱气相色谱测定法

Six-way valve gas injection-capillary column gas chromatography in the determination of methane in the air of workplace in oil and gas field industry

目的建立油气田行业的作业场所空气中甲烷的六通阀气体进样-毛细管柱气相色谱测定法。方法作业场所空气用铝箔采气袋采样后,使用六通阀气体进样,HP-INNOWAX毛细管色谱柱分离,火焰离子化检测器检测。结果在选定的实验条件下,甲烷的检出限为4.35μg/L;在0～424.10μg/L浓度范围内线形良好,相关系数为0.999 95;加标回收率在98.0%～100.1%之间;相对标准偏差(RSD)为0.9%～1.8%。结论该法具有灵敏度高、线形范围宽、准确度好、重复性好、分析速度快、样品保存时间长等优点,适合油气田行业的作业场所空气中甲烷的测定。

[Objective]To establish the six-way valve gas injection-capillary column gas chromatography in the determination of methane in the air of workplace in oil and gas field industry.[Methods]The air samples were collected from workplaces by aluminum foil gas collecting bag,the six-way valve gas injection was conducted,HP-INNOWAX capillary column was applied for separation,and the flame ionization detector was adopted for test.[Results]Under the selected experimental conditions,the detection limit of methane was 4.35 μg/L.The linear range was between 0-424.10 μg/L,the correlation coefficient was 0.999 95,the recovery of standard addition was 98.0%-100.1%,and the relative standard deviation（RSD） was 0.9%-1.8%.[Conclusion]The method has the advantages of good sensitivity,wide linear range,high accuracy,good reproducibility,rapid analysis and longer preservation time of samples,which is suitable for the determination of methane in the air of workplace in oil and gas field industry.