EVALUASI MASALAH KEPASIRAN DAN WATER CONING PADA SUMUR MINYAK VERTIKAL, LAPANGAN “ID”, KALIMANTAN TIMUR - Isnu Daryanto (Jurnal Eksakta Kebumian, 2021)
AbstrakKelebihan produksi air dan pasir merupakan salah satu masalah yang umum dalam memproduksikan minyak bumi. Analisa terhadap masalah ini kemudian menjadi asset berharga dalam memaksimalkan usaha perolehan minyak bumi. Berangkat dari alasan tersebut, penulis mengajukan penelitian masalah kepasiran dan water coning di Blok Sanga-Sanga, Kalimantan Timur. Analisa yang berupa evaluasi ditargetkan pada reservoir dengan limitasi seperti karakteristik reservoir lensa dengan lingkungan pengendapan delta yang dibor secara vertikal menembus beberapa reservoir minyak bumi. Dimana, secara umum reservoir yang ada adalah batuan pasir yang memiliki drive mechanism kombinasi yang didominasi Water Drive.Untuk masalah water coning dilakukan pengamatan terhadap data produksi, khususnya water cut dimana kenaikan yang signifikan merupakan ciri terjadinya water coning. Kemudian, dilakukan Chan’s Diagnostic Plot dengan membandingkan WOR/WOR’ terhadap waktu yang akan dianalisa lebih lanjut dengan perhitungan laju alir kritis. Dari hasil plot tersebut, nantinya akan dapat dibedakan mana sumur yang mengalami water coning atau water channeling. Hasil tersebut akan divalidasi dengan perhitungan laju alir kritis. Ada beberapa metode yang digunakan dalam perhitungan laju alir kritis sumur vertikal, yaitu Metode Meyer-Garder, Metode Schols, Metode Chaperson, Metode Hoyland-Papatzacos-Skjaeveland, Metode Chierici-Ciucci dan Metode Chaney dkk. Jika laju alir produksi atau aktual berada diatas laju alir kritis maka dapat dipastikan reservoir mengalami masalah water coning. Terakhir, akan diperkirakan breakthrough time melalui metode Sobocinski-Cornelius.Kata kunci: Water coning, Water Channeling, Laju Alir Kritis, Breakhthrough Time, Masalah Kepasiran. AbstractOverproduction of water and sand is one of several common issues in producing oil. Analysis towards this problem becomes a valuable asset in maximizing oil recovery. Based on this reason, writer pursues research of sand problem and water coning at Sanga-Sanga Block, East Kalimantan. Analysis as the evaluation is targeted on reservoir by certain limitations such as lenses reservoir characteristic with deltaic precipitation environment which was drilled vertically through several reservoirs. In general, the reservoir is sandstone which has combination drive mechanism which is dominated by water drive.Then, calculation is held towards critical rate that will be further analyzed with Chan’s Diagnostic Plot by comparing WOR/WOR’ versus time. From the plotting, later we will able to differentiate which well encountered water coning and/or just water channeling In water coning analyses, observation was done towards production data, spesifically water cut where significant rise marks the existence of water coning. Then, Chan’s Diagnostic plot was conducted by comparing WOR/WOR’ to time which will be analyse in advance by the critical rate. From the plot, later on will be able to differentiate wells that experienced water coning or water channeling. The result will be validated with the critical rate calculation. There are several methods on calculating critical rate in vertical well, which are Meyer-Garder Method, Schols Method, Chaperson Method, HoylandPapatzacos-Skjaeveland Method, Chierici-Ciucci Method dan Chaney et al Method. If production rate or actual rate over the critical rate then it divined the existence of water coning in the reservoir. Last, by the method of Sobocinski-Cornelius will be calculated the breakthrough time. Keyword: Water coning, Water Channeling, Critical Flow Rate, Breakhthrough Time, Sand Problem.