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Comparison of CSS and SAGD in Cold Lake

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Comparison of CSS and SAGD in Cold Lake University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies The Vault: Electronic Theses and Dissertations 2015-05-04 Comparison of CSS and SAGD in Cold Lake Shayganpour, Farshid Shayganpour, F. (2015). Comparison of CSS and SAGD in Cold Lake (Unpublished master's thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/25374 http://hdl.handle.net/11023/2240 master thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca UNIVERSITY OF CALGARY Comparison of CSS and SAGD in Cold Lake By Farshid Shayganpour A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTERS OF ENGINEERING DEPARTMENT OF CHEMICAL & PETROLEUM ENGINEERING CALGARY, ALBERTA APRIL, 2015 © Farshid Shayganpour, 2015 ABSTRACT Several methods are being used to recover buried heavy oil or bitumen deposits within oil- sands reservoirs. Cyclic Steam Stimulation (CSS) has been a commercial recovery process since the mid 1980’s in the Cold Lake area in northeast Alberta. Also, Several Steam-Assisted Gravity Drainage (SAGD) projects are in operation in different types of reservoirs in the Cold Lake area. There is a debate over whether CSS is more efficient in the Cold Lake reservoirs or SAGD. It is very important for producers to know broadly about the performance and efficiency of the oil recovery process. This helps them to select the proper recovery process. The main objective of this study was aimed to review and compare the performance and efficiency of the CSS and SAGD processes in Cold Lake area. In the current survey, the field data gathered since the start of the operation until almost the present time and the performance comparison were carried out based on the acquired data. Then two robust models were built using CMG-STARS for both CSS and SAGD processes. In both models, averaged reservoir properties that represent mean values of Cold Lake reservoir was incorporated. The production profile of both processes were history matched and the validity of the models confirmed through sensitivity studies. The performance indicators such as cumulative steam oil ratio, recovery factor and cumulative produced oil values were obtained from the models and compared. Finally, sensitivity scenarios were performed on both models to evaluate and compare the performance of each reservoir under different recovery mechanism. II AKNOWLEDGEMENTS I would like to express my gratitude to my supervisor, Dr. Ian Gates, whose expertise, and understanding added considerably to my graduate experience. Also I must express my sincere appreciation to Dr. Alex De Visscher for his constant source of knowledge and advice and support. I must also acknowledge Dr. Mohammad Tavallali for his valuable suggestions and provision in this study. I would also like to thank my family for the support they provided me through my entire life and in particular, I must acknowledge my wife and best friend, Narges, without whose love and encouragement, I would not have finished this thesis. III DEDICATION This is dedicated to my dearest wife Narges for her endless love support and encouragement, to my wonderful daughter Tina and to my great friend Mohammad Tavallali. IV TABLES OF CONTENTS ABSTRACT ..............................................................................................................II AKNOWLEDGEMENTS ....................................................................................... III DEDICATION ........................................................................................................ IV LIST OF TABLES ............................................................................................... VIII LIST OF FIGURES ................................................................................................. IX LIST OF SYMBOLS, ABBREVIATIONS AND NOMENCLATURE ................. XIII CHAPTER 1: INTRODUCTION .............................................................................. 1 1.1 Oil Sands .......................................................................................................... 2 1.2 Bitumen Production from Oil Sands Formations ............................................... 3 1.3 Brief Geological Description of the Cold Lake Oil Sands Deposit .................... 5 1.4 Brief Geological Description of the Athabasca Oil Sands Deposit ..................... 6 1.5 Comparison of Mineralogy and Rock Properties for Cold Lake and Athabasca . 7 1.6 Fluid Properties ................................................................................................ 7 1.7 Recovery Techniques ........................................................................................ 8 1.7.1 Primary Recovery ....................................................................................... 8 1.7.2 Thermal Recovery....................................................................................... 9 1.7.2.1 Cyclic Steam Stimulation (CSS) ....................................................... 10 1.7.2.2 Steam-Assisted Gravity Drainage (SAGD) ....................................... 12 1.7.2.3 Toe-to-Heel-Air-Injection (THAI) .................................................... 13 1.8 Research Questions......................................................................................... 14 1.9 Thesis Outline ................................................................................................ 14 CHAPTER 2 LITERATURE REVIEW ................................................................... 15 2.1 Literature review ............................................................................................ 15 2.2 Cyclic Steam Stimulation (CSS) ..................................................................... 16 2.2.1 Physics of CSS.......................................................................................... 16 2.2.2 Geo-mechanics of CSS ............................................................................. 18 2.2.3 Three phase phenomena in CSS ................................................................ 20 2.2.4 Field practice ............................................................................................ 20 V 2.2.5 Well/Completion Design ........................................................................... 26 2.3 SAGD............................................................................................................. 26 2.3.1 Physics of SAGD ...................................................................................... 27 2.3.2 Geo-mechanics of SAGD .......................................................................... 29 2.3.3 Three phase phenomena in SAGD............................................................. 30 2.3.4 Field Practice ............................................................................................ 33 2.3.5 Well/completion design in SAGD ............................................................. 40 2.4 What is missing in the literature? .................................................................... 42 CHAPTER 3: ANALYSIS OF FIELD DATA ......................................................... 43 3.1 Introduction .................................................................................................... 43 3.2 Cold Lake In situ Projects in the Clearwater Formation .................................. 43 3.3 Production Data .............................................................................................. 43 3.3.1 CNRL-CSS ............................................................................................... 43 3.3.2 Imperial Oil Limited-CSS ......................................................................... 48 3.3.3 CNRL-Burnt Lake-SAGD......................................................................... 52 3.3.4 HUSKY-Tucker Lake-SAGD ................................................................... 56 3.3.5 OSUM-SAGD .......................................................................................... 60 3.4 performance comparison ................................................................................. 64 3.5 Discussion ...................................................................................................... 68 CHAPTER 4: RESERVOIR SIMULATION ........................................................... 69 4.1 Reservoir Description ..................................................................................... 72 4.2 Fluid Properties .............................................................................................. 72 4.3 Rock-Fluid Properties ..................................................................................... 74 4.4 Reservoir Modelling ....................................................................................... 73 4.4.1 Steam Assisted Gravity Drainage (SAGD) in Burnt Lake,Clearwater Formation ......................................................................................................... 73 4.4.1.1 Calibration of SAGD Model ............................................................. 76 4.4.1.2 Validation of Calibrated Model .......................................................
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