North Field, Qatar: A Study of Condensate Blockage and Petroleum Streams Management M.Sc. Thesis BY ARIF KUNTADI SUPERVISOR: PROF. CURTIS H. WHITSON Trondheim, June 2004 DEPARTMENT OF PETROLEUM ENGINEERING AND APPLIED GEOPHYSICS NORWEGIAN UNIVERSITY OF SCIENCE AND TECHNOLOGY North Field, Qatar: A Study of Condensate Blockage and Petroleum Streams Management NTNU Norges teknisk-naturvitenskapelige universitet Fakultet for ingeniørvitenskap og teknologi Faculty of Engineering and Technology Studieprogram i Geofag og petroleumsteknologi Study Programme in Earth Sciences and Petroleum Engineering Institutt for petroleumsteknologi og anvendt geofysikk Department of Petroleum Engineering and Applied Geophysics HOVEDOPPGAVEN/DIPLOMA THESIS/MASTER OF SCIENCE THESIS Kandidatens navn/ The candidate’s name: ARIF KUNTADI Oppgavens tittel, engelsk/Title of Thesis, English: North Field, Qatar: A Study of Condensate Blockage and Petroleum Streams Management Utfyllende tekst/Extended text: This thesis aims to study the behaviour North Field gas condensate reservoir mainly in term of condensate blockage phenomenon near the wellbore which gives very significant well deliverability loss. Radial and Full Field reservoir model are simulated and some observations at the region near the wellbore have been done. Petroleum streams management has been developed for North Field to generate a complete compositional streams database. Studieretning/Area of specialization: Reservoir Engineering Fagområde/Combination of subjects: PVT, Reservoir Simulation and Petroleum Streams Engineering Tidsrom/Time interval: January –June 2004 Faglærer/Teacher Original: Student Kopi: Fakultet Kopi: Institutt M.Sc. Thesis, IPT, 2004 Page 2 of 125 North Field, Qatar: A Study of Condensate Blockage and Petroleum Streams Management Acknowledgments I wish to express my sincerest gratitude to my supervisor Professor Curtis H. Whitson for his invaluable personal and academic guidance throughout the whole work of this thesis and also for his fresh ideas and insights when discussing every topic in this thesis. I especially thank to Dr. Mohammad Faiz ul Hoda and Dr. Knut Uleberg who helped me to develop petroleum streams management of North Field and with whom I had interesting discussions for improving the quality of this thesis. I also thank to QUOTA Programme for giving me financial support in two years studying at the Department of Petroleum Engineering and Applied Geophysics of the Norwegian University of Science and Technology. I would like to give my thanks to the office staffs at IPT, NTNU, and also all my friends for their cares and “smart” discussions in this latest two years. Finally, I would like to dedicate this thesis to my parents who always give me constant encouragement. I am indebted to my wife, Astri, who always be patient to stand by me and encourage me to finish my study and thesis. Last but not least, I am also indebted to my son, Akhtar, a “little star” who has been my new spirit to finish this thesis. Trondheim, June 2004 Arif Kuntadi M.Sc. Thesis, IPT, 2004 Page 3 of 125 North Field, Qatar: A Study of Condensate Blockage and Petroleum Streams Management Table of Contents ACKNOWLEDGMENTS.........................................................................................................3 TABLE OF CONTENTS ..........................................................................................................4 ABSTRACT ...............................................................................................................................6 1. INTRODUCTION .........................................................................................................7 2. EQUATION OF STATE (EOS) AND RESERVOIR MODEL ................................8 2.1. EOS MODEL.....................................................................................................................8 2.2. RESERVOIR MODEL ..........................................................................................................8 3. CONDENSATE BLOCKAGE PHENOMENON.....................................................10 3.1. INTRODUCTION ...............................................................................................................10 3.2. GAS CONDENSATE RATE EQUATION ................................................................................10 3.2.1. Flow Regions.........................................................................................................11 3.2.2. Calculating Pseudopressure..................................................................................11 3.3. RELATIVE PERMEABILITY NEAR WELLBORE....................................................................13 3.4. RELATIVE PERMEABILITY IN KHUFF FORMATION............................................................14 4. RADIAL MODEL SIMULATION ............................................................................17 4.1. RESERVOIR MODEL DESCRIPTION....................................................................................17 4.1.1. Gridding and Layering..........................................................................................17 4.1.2. Permeability distribution.......................................................................................17 4.2. RADIAL MODEL SIMULATION AND RESULTS ..................................................................18 4.3. OBSERVATION AT AREA NEAR WELL BORE......................................................................18 4.3.1. Gas Rate distribution.............................................................................................18 4.3.2. Capillary number profile.......................................................................................19 4.3.3. Oil Gas Ratio (OGR) profile .................................................................................19 4.3.4. Oil Saturation profile ............................................................................................19 4.3.5. Correlations...........................................................................................................19 4.3.6. Permeability Effect ................................................................................................20 5. SKIN FACTOR PREDICTION.................................................................................23 5.1. CONDENSATE SKIN FACTOR PREDICTION ........................................................................23 5.2. EFFECTIVE SKIN FACTOR PREDICTION.............................................................................25 6. SENSITIVITY ANALYSIS ........................................................................................27 6.1. COREY-LIKE EQUATION EXPONENT AND PRODUCTION TUBING SIZE...............................27 6.2. PRESSURE CONSTRAINTS AND TUBING SIZE ...................................................................27 6.3. PERMEABILITY DISTRIBUTION.........................................................................................28 6.3.1. Radial Model Simulation.......................................................................................28 6.3.2. Full Field Model Simulation .................................................................................28 7. PETROLEUM STREAM MANAGEMENT ............................................................30 7.1. PETROLEUM STREAMS MANAGEMENT IN NORTH FIELD ..................................................30 7.2. GENERATING STREAMS DATABASE OF NORTH FIELD......................................................32 M.Sc. Thesis, IPT, 2004 Page 4 of 125 North Field, Qatar: A Study of Condensate Blockage and Petroleum Streams Management 7.3. SOME APPLICATIONS IN STREAMS DATABASE .................................................................33 8. CONCLUSIONS..........................................................................................................35 NOMENCLATURE ................................................................................................................36 REFERENCES ........................................................................................................................39 TABLES ...................................................................................................................................40 FIGURES .................................................................................................................................47 APPENDIX A.........................................................................................................................106 1. FULL FIELD RESERVOIR MODEL DATASET ...................................................................106 2. RADIAL RESERVOIR MODEL DATASET .........................................................................112 APPENDIX B.........................................................................................................................119 1. EXTRACT OF MAIN STREAM FILE WHICH IS CONVERTED FROM THE SIMULATION RESULT STREAMS.......................................................................................................................119 2. EXTRACT OF WELL STREAM FILES WHICH IS THE RESULT OF FILTERING OPERATION OF MAIN STREAM FILE.......................................................................................................120 3. EXTRACT OF AVERAGE WELL STREAM FILES WHICH IS THE RESULT OF AGGREGATION AND AVERAGING OPERATIONS OF WELL STREAM FILE. .........................................................121 4. EXTRACT OF