Aplikasi capillary string untuk injeksi surfaktan dalam penanggulangan liquid loading pada sumur A1 dan A2 di lapangan Y
D i Lapangan “Y†Sumur A1 dan Sumur A2 merupakan sumur tua yang telah mengalami produksi penurunan gas. Salah satu problem produksi sumur gasadalah terakumulasinya sejumlah liquid di dasar sumur akibat terjadinya penurunan kemampuan gas untuk mengangkat cairan atau disebut dengan liquid loading. Jika liquid terakumulasi di dasar sumur akan menyebabkan gas tidak bisa terproduksi yang menyebabkan sumur harus ditutup. Oleh sebab itu maka dilakukan metode delikuifikasi yaitu dengan injeksi kimia (surfactant) ke dalam sumur dengan tujuan menurunkan tegangan permukaan dan membentuk foam, sehingga liquid dapat terangkat ke permukaan dan laju produksi gas meningkat.Pada sumur A-1 laju kritis lebih kecil daripada laju gas yaitu laju kritis sebesar 0,28 MMscf/day dan laju alir gas sebesar 0,37 MMscf/Day. Namun perhitungan laju alir kritis pada sumur A-2 lebih besar daripada laju alir gasnya dimana laju kritis sebesar 0,54 MMscf/Day dan laju alir gasnya sebesar 0,143 MMscf/Day dapat disimpulkan sumur A-2 mengalami liquid loading. Sumur A-1 dan sumur A-2 di pasang capillary string. Pada sumur A-1 dilakukan hanya tiga kali injeksi foam dikarenakan sumur yang sudah optimum dan tidak ada kenaikan pada laju alir gas dan laju alir air. Pada sumur A-2 terjadi peningkatan produksi, sehingga dapat mengangkat liquid ke permukaan. Karena itu, Injeksi foam pada sumur A-2 dilakukan secara continue.
I n Field “Yâ€, Well A1 and A2 are old oil wells which had been decreased in production. One of the problem is the amount of liquid accumulated in the bottom of the well due to the decrease of the well’s ability to lift liquid or gas which is called liquid loading. With the liquid accumulated at the bottom of the well, it causes the gas cannot be produced, and will lead to well abandonment. Therefore, deliquification method applied by injecting chemicals (surfactant) into the well, with the aim of decreasing the surface tension and create foam, with the result that the liquid can be lifted and gas production rate will increase.At Well A-1, critical flow is lower than the gas flow, with the critical flow, with 0,28 MMSCF/day of critical flow and 0.37 MMscf/day of gas flow. However,the calculation of critical flow for well A- 2 is bigger than the gas flow, where thecritical flow is up to 0,54 MMscf/d and 0,143 MMscf/d for the gas flow. It can beconcluded well A-2 that liquid loading was occurred. Capillary strings were mounted in well A-1 and A-2. Intermittent foam injection is selected for A-1 well since this well head reached its optimum condition. Morevore, gas rate and water rate remain the same. Production increases at well A- 2, allowing the liquid to be lifted to surface. Therefore, Foam injection applied continuously to well A-2.