Investigation of the effect of diethylene triamine pentaacetic acid chelating agent as an enhanced oil recovery fluid on wettability alteration of sandstone rocks  

作　　者：PARHIZGAR KERADEH Mahsa TABATABAEI-NEZHAD Seyyed Alireza 

机构地区：[1]Faculty of Petroleum and Natural Gas Engineering,Sahand Univensity of Technology,Tabriz 5135-1996,Iran

出　　处：《Petroleum Exploration and Development》2023年第3期675-687,共13页石油勘探与开发（英文版）

摘　　要：This study used the diethylene triamine pentaacetic acid(DTPA)-seawater(SW)system to modify the sandstone rock wettability and enhance oil recovery.The investigation involved conducting wettability measurement,Zeta potential measurement,and spontaneous imbibition experiment.The introduction of 5%DTPA-sW solution resulted in a significant decrease in the rock-oil contact angle from 143°to 23,along with a reduction in the Zeta potential from-2.29 mV to-13.06 mV,thereby altering the rock surface charge and shifting its wettability from an oil-wet state to a strongly water-wet state.The presence or absence of potential determining ions(Ca^(2+),Mg^(2+),SO_(4)^(2-))in the solution did not impact the effectiveness of DTPA in changing the rock wettability.However,by tripling the concentration of these ions in the solution,the performance of 5%DTPA-SW solution in changing wettability was impaired.Additionally,spontaneous imbibition tests demonstrated that the 5%DTPA-SW solution led to an increase in oil recovery up to 39.6%.Thus,the optimum mass fraction of DTPA for changing sandstone wettability was determined to be5%.

关 键 词：wettability alteration DTPA chelating agent Zeta potential spontaneous imbibition enhanced oil recovery 

分 类 号：TE357[石油与天然气工程—油气田开发工程]