مطالعه و ارزيابي تزريق گاز در يكي از ميادين نفت سنگين جنوب غربي ايران

Studying and evaluating gas injection in heavy oil fields of southwestern Iran

ﻳﻜﻲ ﺍﺯ متداولترين ﺭﻭﺵ ﻫﺎﻱ ﺍﻓﺰﺍﻳﺶ ﺑﺎﺯﻳﺎﻓﺖ ﻧﻬﺎﻳﻲ ﻧﻔﺖ، ﺗﺰﺭﻳﻖ ﮔﺎﺯ ﺩﺭ ﻣﺨﺰﻥ ﺍﺳﺖ. ﺗﺰﺭﻳﻖ ﮔﺎﺯ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﻪ ﺻﻮﺭﺕ ﺗﺰﺭﻳﻖ ﻣﺴﺘﻘﻴﻢ ﺩﺭﻭﻥ ﻛﻼﻫﻚ ﮔﺎﺯﻱ ﻭ ﻳﺎ ﺑﻪ ﺻﻮﺭﺕ ﺗﺰﺭﻳﻖ ﺍﻣﺘﺰﺍﺟﻲ ﺻﻮﺭﺕ ﭘﺬﻳﺮﺩ .تزريق گاز، يا به منظور تغيير گرانروي نفت و يا به منظور اثرات افزايش فشار انجام مي¬پذيرد ﻛﻪ ﺍﻳﻦ ﺍﻣﺮ ﻣﻮﺟﺐ ﺗﺜﺒﻴﺖ ﻭ ﻳﺎ ﺍﻓﺰﺍﻳﺶ ﺍﻧﺮژﻱ ﻣﺨﺰﻥ ﻣﻲ ﮔﺮﺩﺩ. ﺗﺰﺭﻳﻖ ﮔﺎﺯ ﺩﺭ ﻣﺨﺎﺯﻥ ﺟﻨﻮﺏ ﻏﺮﺏ ﺍﻳﺮﺍﻥ ﺑﻪ ﻋﻠﺖ ﺩﺭ ﺩﺳﺘﺮﺱ ﺑﻮﺩﻥ ﮔﺎﺯ، ﺳﺎﺯﮔﺎﺭﻱ ﺑﺎ ﻣﺨﺰﻥ ﻭ ﻫﻤﭽﻨﻴﻦ امكان ﺑﺎﺯﻳﺎﻓﺖ ﮔﺎﺯ ﺗﺰﺭﻳﻖ ﺷﺪﻩ ﺩﺭ ﻣﺨﺰﻥ ﻣﺘﺪﺍﻭﻝ ﺗﺮﻳﻦ ﺭﻭﺵ ﻧﮕﻬﺪﺍﺷﺖ ﻳﺎ ﺍﻓﺰﺍﻳﺶ ﻓﺸﺎﺭ ﻣﺨﺰﻥ ﺍﺳﺖ. ﺗﺰﺭﻳﻖ ﮔﺎﺯ ﺿﻤﻦ ﺍﻓﺰﺍﻳﺶ ﻓﺸــﺎﺭ ﻣﺨﺰﻥ ﻣﻲ ﺗﻮﺍﻧﺪ ﺑﺎﻋﺚ ﺛﺎﺑﺖ ﻣﺎﻧﺪﻥ ﻳﺎ ﺍﻓﺰﺍﻳﺶ ﺿﺮﻳﺐ ﺣﺠﻤﻲ ﻧﻔﺖ ﻣﺨﺰﻥ ﮔﺮﺩﺩ ﻛﻪ ﺍﻳﻦ ﺍﻣﺮ ﺩﺭ ﻧﻬﺎﻳﺖ ﻣﻨﺠﺮ ﺑﻪ ﺍﻓﺰﺍﻳﺶ ﺑﺎﺯﻳﺎﻓﺖ ﻧﻬﺎﻳﻲ ﻧﻔﺖ ﻣﺨﺰﻥ ﺧﻮﺍﻫﺪ ﺷﺪ. ﺩﺭ ﺍﻳﻦ ﻣﻘﺎﻟﻪ ﺁﺛﺎﺭ ﺗﺰﺭﻳﻖ ﮔﺎﺯ ﺑﺮ ﺭﻭﻱ ﻣﺨﺯﻥ سروك ﻳﻜﻲ ﺍﺯ ﻣﻴﺎﺩﻳﻦ ﺟﻨﻮﺏ ﻏﺮﺏ ﺍﻳﺮﺍﻥ ﻛﻪ ﺑﺎ ﻫﺪﻑ ﻧﮕﻬﺪﺍﺷﺖ ﻓﺸﺎﺭ ﻣﺨﺰﻥ و همچنين ﺍﻓﺰﺍﻳﺶ ﺿﺮﻳﺐ ﺣﺠﻤﻲ ﻧﻔﺖ ﻃﺮﺍﺣﻲ ﮔﺮﺩﻳﺪﻩ، ﻣﻮﺭﺩ ﺑﺮﺭﺳﻲ ﻗﺮﺍﺭ ﮔﺮﻓﺘﻪ ﺍﺳﺖ. ﻣﻴﺰﺍﻥ ﻭ ﻧﺤﻮﻩ ﺗﺰﺭﻳﻖ ﮔﺎﺯ ﺩﺭ ﻣﻴﺪﺍﻥ، ﺗﻐﻴﻴﺮﺍﺕ ﻓﺸﺎﺭ ﺳﻴﺎﻻﺕ ﻣﺨﺰﻥ ﻗﺒﻞ ﻭ ﺑﻌﺪ ﺍﺯ ﺗﺰﺭﻳﻖ، ﺗﻐﻴﻴﺮﺍﺕ ﺳﺘﻮﻥ ﻧﻔﺖ ﻭ ﻫﻤﭽﻨﻴﻦ ﺗﻐﻴﻴﺮﺍﺕ ﺧﻮﺍﺹ ﻧﻔﺖ ﻣﺨﺰﻥ ﻭ ﻧﺘﺎﻳﺞ ﻧﺎﺷﻲ ﺍﺯ ﺗﺰﺭﻳﻖ ﮔﺎﺯ ﺩﺭ ﻣﻴﺪﺍﻥ ﻧﻴﺰ ﺗﺸﺮﻳﺢ ﮔﺮﺩﻳﺪﻩ ﺍﺳﺖ.

Gas injection in the reservoir is the one of common to increase ultimate oil recovery. Gas injection can done directly in gas cap or miscible injection. It done to change oil gravity or to increase pressure effects. Gas injection in Iranian south west reservoir is the one of common method to increase or maintenance pressure because gas availability, compatibility with reservoir and the possibility of injected gas recovery.Gas injection while increasing the reservoir pressure also may remain constant or increase reservoir oil volume factor , this leads to increased ultimate oil recovery from reservoir. The studies Works on gas injection in Sarvak reservoir , one of the fields in the Southwest Iran with the aim of maintaining reservoir pressure and increase oil volume factor was designed. Rate and administration of gas injection, reservoir fluid pressure changes before and after the injection, oil column changes as well as changes in reservoir properties and the results of gas injection in the field also been described.