Evaluasi kinerja dan peramalan produksi sumur FW1 dan FW2 menggunakan metode chan dan analisis decline curve
D Dalam kuartal akhir tahun 2017 produksi minyak atau oil recovery pada sumurFW1 dan FW2 di Lapangan X mengalami penurunan. Langkah yang nyata yangdiambil PT. Pertamina EP Asset 1 Field Ramba adalah menganalisis sumur produksikenapa oil recovery nya menurun. Kedua sumur tersebut berada di lapangan onshoreyang dikelola oleh PT Pertamina EP Asset 1 Field Ramba, berlokasi di SumatraSelatan pada formasi Talang Akar.Sumur FW1 dan FW2 dianalisis dengan menggunakan metode Chan’sDiagnostic Plot dan Decline Curve Analysis. Analisis menggunakan Chan’sDiagnostic Plot dilakukan pada kedua sumur menggunakan data produksi minyakdan air untuk mendapatkan water oil ratio (WOR) dan water oil ratio derivative(WOR’). Sedangkan untuk analisis decline curve dilakukan pada data produksiminyak masing-masing sumur. Dalam analisis decline curve untuk setiap sumur,dilakukan Penentuan jenis decline dilakukan dengan metode Trial Error and X2Chisquare, sehingga dapat ditentukan jenis kurva penurunan diantara exponential,hyperbolic atau harmonic decline curve.Hasil dari metode Ghanes Thakur diketahui bahwa reservoir memiliki tenagadorong water drive. Hasil interpretasi menggunakan metode Chan diketahui bahwasumur FW1 mengalami Multilayer Channeling dengan perubahan produksi dansumur FW2 mengalami Water Coning dengan late time channeling. Dari perhitungandecline curve analysis dapat mendapat kumulatif forecast produksi masing-masingsumur. Saat mengalami multilayer channeling sumur FW1 dapat berproduksi sampaidengan Januari 2020 dan pada saat sumur mengalami water coning sumur FW2 dapatberproduksi sampai dengan Februari 2019. Dari perhitungan forecast diketahuibahwa nilai dari Estimated Ultimate Recovery dari lapangan X adalah 1,578,448 Bbldan diperoleh nilai Ultimate Recovery Factor sebesar 39.64%.
I In the final quarter of 2017 oil production or oil recovery in the FW1 and FW2wells in Field X decreased. The real step taken by PT. Pertamina EP Asset 1 FieldRamba is analyzing production wells why the oil recovery is decreasing. The twowells are in an onshore field managed by PT Pertamina EP Asset 1 Field Ramba,located in South Sumatra in the Talang Akar formation.The FW1 and FW2 wells are analyzed using Chan's Diagnostic Plot andDecline Curve Analysis methods. Chan's Diagnostic analysis using the plot carriedout on both wells using oil and water production data to obtain a water oil ratio(WOR) and derivative water oil ratio (WOR '). While for decline curve analysis isdone on the data of oil production of each well. In the decline curve analysis for eachwell, the type of decline is determined by the Trial Error and X2 Chisquare method,so that the type of decline curve can be determined between exponential, hyperbolicor harmonic decline curve.The results of the Ghanes Thakur method note that the reservoir has a drivingforce of water drive. The interpretation results using the Chan method are knownthat the FW1 well experienced Multilayer Channeling with changes in productionand the FW2 well experienced Water Coning with late time channeling. From thecalculation of decline curve analysis, it can get a comparison of oil productionforecast when the well experiences a production problem with oil production forecastwhen the well is normal. When experiencing a multilayer channeling well FW1 canproduce until January 2020 and when the well experiences water coning, the FW2well can produce until February 2019. that the value of Estimated Ultimate Recoveryfrom field X is 1,578,448 Bbl and the Ultimate Recovery Factor value is 39.64%.