DAFTAR ISI
HALAMAN JUDUL .............................................................................
Halaman i
HALAMAN PENGESAHAN ...............................................................
ii
PERNYATAAN KEASLIAN KARYA ILMIAH ................................
iv
HALAMAN PERSEMBAHAN ............................................................
v
KATA PENGANTAR ...........................................................................
vi
RINGKASAN ........................................................................................
vii
DAFTAR ISI .........................................................................................
viii
DAFTAR GAMBAR ............................................................................
xi
DAFTAR TABEL .................................................................................
xiv
BAB I. PENDAHULUAN .....................................................................
1
BAB II. TINJAUAN UMUM LAPANGAN .........................................
7
2.1. Letak Geografis Struktur Jatibarang ................................. 2.2. Sejarah Umum Lapangan ................................................. 2.3. Statigrafi Cekungan Jawa Barat Bagian Utara .................. 2.3.1. Formasi Vulkanik ............................................... 2.3.2. Formasi Cibulakan .............................................. 2.3.2.1. Formasi Cibulakan Bawah ................. 2.3.2.2. Anggota Cibulakan Atas .................... 2.3.3. Formasi Parigi .................................................... 2.3.4. Formasi Cisubuh ................................................. 2.4. Kondisi Reservoir Struktur Jatibarang Lapisan F ............. 2.5. Sejarah Produksi Struktur Jatibarang Lapisan F ............... 2.6. Sejarah Sumur Gas Lift “X” ............................................
7 7 8 9 9 10 10 11 12 12 12 15
BAB III. TEORI DASAR CONTINUOUS GAS LIFT........................
19
3.1. Mekanisme Aliran Dalam Media Berpori......................... 3.1.1. Productivity Index (PI) ....................................... 3.1.2. Inflow Performance Relationship (IPR) ............. 3.1.2.1. Kurva IPR Dua Fasa .......................... 3.1.2.1.1. Persamaan Vogel.............. 3.1.2.1.2. Persamaan Standing ......... 3.1.2.1.3. Persamaan Couto.............. 3.1.2.1.4. Persamaan Horrison ......... 3.1.2.1.5. Persamaan Pudjo Sukarno 3.1.2.2. Kurva IPR Tiga Fasa ......................... 3.1.2.2.1. Persamaan Petrobras ........ 3.1.2.2.2. Persamaan pudjo sukarno .
19 20 21 21 21 24 25 25 26 27 27 34
viii
DAFTAR ISI (Lanjutan) Halaman 3.2. Kinerja Aliran dalam Pipa Vertikal .................................. 3.2.1. Metoda Hagedorn dan Brown ............................. 3.2.2. Metoda Beggs dan Brill ..................................... 3.3. Teori Dasar Continuous Gas Lift...................................... 3.3.1. Prinsip Kerja Gas Lift ......................................... 3.3.2. Instalasi Gas Lift ................................................. 3.3.2.1. Instalasi Terbuka ............................... 3.3.2.2. Instalasi Setengah Tertutup ................ 3.3.2.3. Instalasi Tertutup ............................... 3.3.3. Katub Sembur Buatan ......................................... 3.4. Perencanaan Evaluasi Continuous Gas Lift........................ 3.4.1. Penentuan Letak Titik Injeksi.............................. 3.4.2. Penentuan Spasi Katub Gas Lift .......................... 3.4.3. Penentuan Laju Gas Injeksi Untuk Mendapatkan Produksi Maksimum ........................................... 3.5. Decline Curve ................................................................... 3.5.1. Teori Dasar Metode Decline Curve ..................... 3.5.1.1. Exponential Decline Curve ................ 3.5.1.2. Hyperbolic Decline Curve ................. 3.5.1.3. Harmonic Decline Curve ................... 3.5.2. Metode Penentuan Decline Curve ....................... 3.5.2.1. Metode Loss-Ratio (Arps) ................. 3.5.2.2. Metode Trial-Error ........................... 3.5.2.3. Metode Ekstrapolasi Kurva Fit .......... 3.6. Optimasi Laju Gas Injeksi Software Prosper ..................... 3.6.1. Input Data PVT................................................... 3.6.2. IPR ..................................................................... 3.6.3. Input Gas Lift Data dan Equipment Data............. 3.6.4. Matching VLP dengan IPR Sumur ...................... 3.6.5. Optimasi Laju Gas Injeksi Sumur Gas Lift Software Prosper ................................................ BAB IV.
PERHITUNGAN OPTIMASI LAJU GAS INJEKSI SUMUR GAS LIFT “X” LAPANGAN JATIBARANG ...
4.1. Pengumpulan Data ............................................................ 4.2. Optimasi Laju Gas Injeksi Sumur Gas Lift “X” Dengan Menggunakan Perhitungan Manual ...................... 4.2.1. Penentuan Laju Produksi Sumur ...................... 4.2.2. Optimasi Laju Gas Injeksi Optimum Sumur Gas Lift “X” ........................................ 4.3. Optimasi Laju Gas Injeksi Sumur Gas Lift “X” Dengan Menggunakan Simulator Prosper .................. ix
37 37 41 45 45 47 48 48 49 49 60 60 64 66 72 72 75 79 82 86 86 88 88 90 90 92 93 96 98 101 101 103 103 108 114
DAFTAR ISI (Lanjutan) Halaman 4.3.1. 4.3.2. 4.3.3. 4.3.4.
Input Data PVT ................................................ IPR ................................................................. Input Gas Lift Data Dan Equipment Data ......... Matching VLP (Vertical Lift Performance) Dengan IPR Sumur “X” ................................... 4.3.5. Optimasi Laju Gas Injeksi Optimum Sumur “X” Simulator Prosper .......................... 4.4. Perbandingan Hasil Perhitungan Manual Dengan Simulator Prosper Sumur Gas Lift “X” ............................. 4.5. Pemilihan Periode (Trend) Produksi Untuk Analisa........... 4.5.1 Ekstrapolasi Data Dengan Metode Trial Error .. 4.5.2. Metode Penentuan Kurva Fit ............................ 4.6. Perkiraan Lama Waktu Optimasi Sumur “X” Lapisan F di Lapangan Jatibarang......................................
114 116 118
BAB V. PEMBAHASAN ......................................................................
139
BAB VI. KESIMPULAN ......................................................................
141
DAFTAR PUSTAKA ............................................................................
142
LAMPIRAN ..........................................................................................
143
x
122 123 126 128 130 133 135
DAFTAR GAMBAR Gambar
Halaman
2.1. Peta Prospek Region Jawa ................................................................
7
2.2. Stratigrafi Cekungan Jawa Barat Utara .............................................
8
2.3. Cekungan Jawa Bagian Utara ...........................................................
9
2.4. Peta Struktur Vulkanik Jatibarang ....................................................
15
2.5. Profil Sumur “X” .............................................................................
18
3.1. Grafik IPR Dua Fasa ........................................................................
22
3.2. Grafik IPR Vogel untuk Solution Gas Drive .....................................
23
3.3. Kurva Composite IPR ......................................................................
28
3.4. Kurva Composite IPR ......................................................................
32
3.5. Korelasi Friction Faktor Untuk Aliran Dua Fasa ..............................
38
3.6. Korelasi Faktor Hold Up ..................................................................
39
3.7. Korelasi Untuk Faktor Koreksi Sekunder .........................................
40
3.8. Korelasi Untuk Viscosity Number .....................................................
40
3.9. Mekanisme Operasi Continuous flow gas lift ...................................
45
3.10. Tipe Instalasi gas lift ......................................................................
49
3.11. Valve Unbalance Pressure / Casing Operated ...............................
51
3.12. Unbalance Bellow Valve dengan Pressure Charge Dome dan Spring sebagai Loading Element ..............................................
54
3.13. Balance Casing Pressure Operated Valve ......................................
56
3.14. Continuouc Flow Valve ..................................................................
57
3.15. Fluid Operated Valve .....................................................................
57
3.16. Ilustrasi Penentuan Letak Titik Injeksi............................................
61
3.17. Ilustrasi Spasi Katub Gas Lift .........................................................
64
3.18. Titik Potong Kurva IPR pada berbagai harga GLR .........................
70
3.19. Plot Kurva Gas Injection (Mscfd) vs Production Rate (STBO/D) ...
71
3.20. Beberapa Tipe Grafik Antara q 0 vs t dan qo vs Np Pada Ketiga Jenis Decline Curve ...................................................
73
3.21. Grafik Hubungan Antara q o vs t Pada Tipe Exponential Decline.....
77
3.22. Grafik Hubungan Antara q o vs Np Pada Tipe Exponential Decline .
78
3.23. Grafik Hubungan Antara q o vs t Pada Tipe Hyperbolic Decline ......
80
xi
DAFTAR GAMBAR (Lanjutan) Gambar
Halaman
3.24. Grafik Hubungan Antara q o vs t Pada Tipe Harmonic Decline........
83
3.25. Grafik Hubungan Antara q o vs Np Pada Tipe Harmonic Decline ....
84
3.26. Tampilan Awal Sofware Prosper ....................................................
90
3.27. Option Input Software Prosper .......................................................
91
3.28. Input PVT Software Prosper ...........................................................
91
3.29. Match Data (PVT) ..........................................................................
92
3.30. Regression (PVT)...........................................................................
92
3.31. IPR Input Data Software ................................................................
93
3.32. Input Data Gas Lift.........................................................................
94
3.33. Deviation Survey ............................................................................
94
3.34. Downhole Equipment .....................................................................
95
3.35. Draw Downhole .............................................................................
95
3.36. Geothermal Gradient ......................................................................
96
3.37. Correlation Comparison ................................................................
97
3.38. VLP IPR Matching .........................................................................
98
3.39. Titik Potong Kurva Inflow (IPR) dengan kurva outflow (Pwf pada berbahai harga GLR injeksi) Sumur Gas Lift...................
99
3.40. Grafik Laju Gas Injection Optimum (MMscf/d) vs Laju Produksi minyak (Bopd) Sumur Gas Lift ..........
100
4.1. Inflow Performance Relationship Sumur “X” ..................................
107
4.2. Titik Potong Kurva Inflow (IPR) dengan kurva outflow (Pwf pada berbahai harga GLR injeksi) Sumur “X” ........................
110
4.3. Plot Kurva Laju Gas Ijection (MMscf/d) vs Oil Rate (STBO/D) Sumur “X” .......................................................................................
113
4.4. Tampilan Awal Software Prosper ....................................................
114
4.5. Option Input Software Prosper ........................................................
114
4.6. Input PVT Software Prosper............................................................
115
4.7. Match Data (PVT) ..........................................................................
116
4.8. Regression (PVT)............................................................................
116
4.9. IPR Input Data Simulator .................................................................
117
xii
DAFTAR GAMBAR (Lanjutan) Gambar
Halaman
4.10. Kurva IPR Sumur “X” Simulator Prosper .......................................
118
4.11. Input Data Gas Lift.........................................................................
119
4.12. Deviation Survey ............................................................................
119
4.13. Downhole Equipment .....................................................................
120
4.14. Draw Downhole .............................................................................
121
4.15. Geothermal Gradient .....................................................................
121
4.16. Correlation Comparison ................................................................
122
4.17. VLP IPR Matching .........................................................................
123
4.18. Titik Potong Kurva Inflow (IPR) dengan kurva outflow (Pwf pada berbagai harga GLR injeksi) Sumur “X” Perhitungan Simulator.....
124
4.19. Hasil Perhitungan Simulator ...........................................................
125
4.20. Kurva Laju Gas Ijection (MMscf/d) vs Oil Rate (STBO/D) Sumur “X” Simulator Prosper ........................................................
126
4.21. PenentuanTrend Produksi Untuk Analisa .......................................
129
4.22. Grafik Perkiraan Lama Waktu Produksi Sumur Gas Lift “X” Lapisan F ..................................................................
137
xiii
DAFTAR TABEL Tabel
Halaman
II.1. Data Sifat Fisik Batuan dan Sifat Fisik Fluida Lapisan F .................
13
II.2. Sejarah Sumur Gas Lift “X” ...........................................................
15
III.1. Konstanta c 1 , c 2 , c 3 dan c 4 ...........................................................
26
III.2. Konstanta Cn Untuk Masing-masing An ........................................
35
III.3. Konstanta a, b dan c untuk Setiap Pola Aliran ................................
44
III.4. Konstanta d, e, f dan g untuk Setiap Pola Aliran ............................
44
III.5. Batasan Ukuran Tubing dan Laju Produksi Untuk Continous gas Lift ...............................................................
47
III.6. Contoh Tabel Inflow Performance ..................................................
68
III.7. Contoh Tabel Outflow Flowline Requirment .................................
69
III.8. Contoh Tabel Outflow Tubing Requirment ....................................
69
III.9. Contoh Tabel GLR injeksi, Laju Produksi, dan Laju Gas Injeksi ...
70
III.10. Decline Curve Equation ...............................................................
85
IV.1. Hasil Perhitungan qo, qw dan qt Sumur “X” Pada Berbagai Harga Pwf .............................................................
106
IV.2. Tabel Outflow Tekanan Alir Dasar Sumur Berbagai GLR injeksi Sumur “X” ................................................................
109
IV.3. Hasil Dari Titik Potong Kurva Inflow dan Outflow Sumur “X” ......
111
IV.4. Berbagai Harga Laju Gas Injeksi Sumur “X” Perhitungan Manual .
113
IV.5. Spasi Valve Sumur “X”.................................................................
119
IV.6. Tabel Hasil Qliquid Untuk Berbagai Harga GLRinjeksi ................
124
IV.7. Tabel Hasil Perbandingan Perhitungan Manual Dan Simulator Prosper .................................................................
127
IV.8. Pemilihan Trend Produksi Untuk Analisa .......................................
128
IV.9. Penentuan Tipe Decline Curve Menggunakan Metode Trial Error .
132
IV.10. Penentuan Tipe Decline Curve Menggunakan Metode Kurva fit...
134
IV.11. Perkiraan Perilaku Produksi Setelah Optimasi ..............................
135
xiv
