带压含硫气田水中H2S的测定

Determination of H2S in the pressurized sulfur-containing gas field water

关键词:  气田水  带压溶液  H₂S  碘量法 

Key words:  gas field water  pressurized solution  hydrogen sulfide  iodometry

摘要:

目的 捕集和检测带压含硫气田水常规减压取样过程排放闪蒸气中损失的H₂S组分,以实现带压含硫气田水中H₂S含量更加准确的测定,为优化和提升闪蒸气H₂S处理装置的设计和净化效率提供数据支撑。方法 针对当前气田水减压平衡处理后H₂S测定结果明显偏低的问题,从带压液体取样和H₂S气体分析检测两个方面开展研究,讨论了取样装置、取样方法、分析检测方法、样品前处理、酸液用量和汽提时间等参数的影响。结果 实现了等压取样,汽提时间为5 min,样品无须过滤前处理,解吸液为去离子水,以经典碘量法检测H₂S。结论 通过比较实际样品带压和减压条件下H₂S含量的测定结果,表明该技术对准确测定带压含硫气田水中H₂S含量更加可靠,并将对其他带压溶液中溶解性气体的测定提供可借鉴的思路。 

Abstract:

Objective Capturing and detecting the lost H₂S component in the emitted flash gas during conventional decompression sampling towards pressurized sulfur-containing gas field water can realize the more accurate determination of its H₂S content, and provide data support for optimizing and upgrading the design and purification efficiency of H₂S treatment unit over flash gas. Methods Considering the problem that the determination result of H₂S for gas field water after the decompression and balance treatment are obviously low, this work conducts the research from the aspects of pressurized liquid sampling and H₂S gas analysis to discuss the influences of parameters including sampling device, sampling method, analysis method, sample pretreatment, acid consumption and stripping time. Results Isobaric sampling is realized, stripping time is 5 min, no pre-filtration treatment is required, deionized water is chosen as the desorption liquid, and the classical iodometry is used as the detection method for hydrogen sulfide. Conclusion sBy comparing the determination results of H₂S content upon actual samples under pressure and decompression conditions, it shows that this technology is more reliable for accurate determination of hydrogen sulfide content in pressurized sulfur-containing gas field water, and will also provide a promising strategy for determination of dissolved gas in other pressurized solutions.