文章基本信息

标题：A novel technique for obtaining representative water samples during CO2 core-flooding experiments on chalk at reservoir conditions
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作者：Claus Kjøller ; John Zuta
期刊名称：Geological Survey of Denmark and Greenland Bulletin
印刷版ISSN：1604-8156
出版年度：2014
卷号：31
页码：27-30
语种：English
出版社：De Nationale Geologiske Undersoegelser for Danmark og Groenland
摘要：Tere is a huge potential for using CO2 gas to recover additional oil afer water ﬂooding in reservoir chalk. However,the injection of CO2 into chalk reservoirs will disturb thechemical equilibrium between formation water, injectionwater and chalk. A proper understanding of these CO2-induced interactions and the resulting changes in the physicalproperties at representative reservoir conditions is required.Unfortunately, reliable chemical data are rare because datacannot be acquired directly at reservoir conditions withpresent-day techniques. In published experiments, watersamples are in many cases obtained at atmospheric conditions with the aid of a back-pressure regulator. Tus, watersamples are not representative of in situ reservoir conditionsand if proper care is not taken, the collected data cannot beused to judge the magnitude of the chemical reactions takingplace at reservoir conditions. However, in some cases waterobtained at laboratory conditions can give information onin situ reservoir conditions by using geochemical speciationmodels to account for dissolved gases that are lost from theefuents during sampling (Bachu & Adams 2003).