Tối ưu hóa điều kiện vận hành SAGD bằng Response Surface - Nguyen Xuan Huy

Response Surface Optimization for Operating Conditions in Comprehensive SAGD Performance NGUYEN XUAN HUY The Graduate School of Sejong University Department of Energy and Mineral Resources Engineering Response Surface Optimization for Operating Conditions in Comprehensive SAGD Performance NGUYEN XUAN HUY A Doctoral Thesis Submitted to the Department of Energy and Mineral Resources Engineering and Graduate School of Sejong University in partial fulfillment of the requirements for the degree of Doctor of Engineering May 2012 Approved by Prof. Wisup Bae Major Advisor This certifies that the dissertation of Nguyen Xuan Huy is approved. Professor Taewoong Chung Professor Wisup Bae Professor Jonggeun Choi Professor Kyungiun Jun Professor Myung Jin Nam The Graduate School of Sejong University May, 2012 Dedication To my parents and my younger sister and brother Acknowledgment My name is Huy Xuan Nguyen. I have over 10 years experience in the area of petroleum geology and reservoir simulation in the oil and gas industry.

(2004) degrees in petroleum engineering and MBA degree (2008) in petroleum economic from Ho Chi Minh University of Technology as considered the top university with the high quality education in Vietnam. I have positioned the lecturer in teaching undergraduate and science research at Faculty of Geology and Petroleum Engineering, Ho Chi Minh City University of Technology since 2003. In 2009, I received the PhD scholarship program in petroleum engineering from Sejong University under the supervisor of Professor Wisup Bae. Currently, my research interested in the section of petroleum economic management, chemical EOR flooding, thermal oil recovery processes, particularly the oil recovery improvement on SAGD process and the application innovative technologies to exploit the unconventional resources based on electromagnetic heating, nuclear energy, single-well SAGD, and operation optimization.

I am author and coauthor of more than 20 technical papers including SCI Journals, SPE, AAPG and international conferences around the world. I would like to express my special appreciation to my supervisor Prof.Wisup Bae for kind support and academic valuable suggestions throughout my work. I also would like to express my sincere thank to the members of petroleum lab in Sejong University Ngoc T. B Nguyen, Cuong Dang, Taemoon Chung, Tho N.

Tu, and Danh H. Nguyen for their generosity and suggestions. Their assistances are essential in performing my research successfully and have made my studying life here more enjoyable and priceless. By the fact of completing this thesis, I am immensely indebted to my parents, Nguyen Xuan Lang and Tran Thi Tuyet Nhung younger sister and brother.

They have encouraged and nurtured in the development of my personality and support any decision and future career direction. Last but not least, I would like to express my sincere thank to my friends in Vietnamese Students Association in Korea for their generosity and help during study time in Korea. Abstract The steam assisted gravity drainage (SAGD) process has proven to be an effective thermal recovery method for heavy oil and bitumen production. However, there has been much dispute over the question of technical and economical risks.

The technical efficiency of the SAGD process depends on two important factors: reservoir properties and operating conditions. The SAGD performance was investigated based on the variables of reservoir properties such as thickness, porosity, permeability, oil saturation, viscosity, rock thermal conductivity, along with operating variables as including preheating, injector/producer spacing, injection pressure, steam injection rate and subcool temperature. In addition, the economic risks associate to the cost of initial investment for building ground facilities, operating costs, and the uncertainties of oil and gas prices. The integration of economic and technical aspects for SAGD performance plays an important role in field operation.

Main problems to solve are how to design optimal operating conditions for a reasonable steam requirement with certain injection pressure to maximize economic feasibility under reservoir conditions. Recently, some innovative techniques based on the background SAGD operation have been applied such as conventional SAGD, Fast-SAGD, Hybrid SAGD, FA-SAGD. Most previous literatures implemented sensitivity analysis and optimization of SAGD performance by classical methods based on numerical simulations lead to a lack of confidence level and ignored interactions effects between considered parameters, which may cause low efficiency issues in a field operation. In addition, the SAGD economic models have not fully information with limited consideration on few factors.

These restrictions can be avoided by the application design of experiment and response surface methodology to determine the optimal operating conditions for the production prediction. Then, discontinuous SAGD technique was operated to control the amount of injected steam at several specific injection time intervals. The results showed that the effect of reservoir parameters on SAGD performance is the most important with order ranking as porosity, thickness, oil saturation, permeability, viscosity, and then interaction factors of reservoir properties. Subsequent to injection pressure and steam injection rate have a greatest effect in operational parameters.

The results of this study showed uncertainties ranking of reservoir and operational parameters are a target for best choice on oil sand projects. The new concept of the discontinuous SAGD process is applied to three major formations of Alberta’s oil sands after optimal operation conditions based on response surface methodology. The results showed that both oil recovery factor and economic profit are much higher than other techniques of Fast-SAGD and conventional SAGD process, especially the effective at deeper burial reservoirs of Clearwater and Bluesky formations. Moreover, amount of steam injection rate and cumulative steam oil ratio (CSOR) reduced significantly to cause lower operating costs as steam cost, led to increase NPV as well as minimal environmental damages.

This study will help to improve heavy oil recovery with the minimal environmental damages and with lower production cost. Table of Contents ASÍT/ACÍ.0 0 0088000094 List of Nomenclature and Abbbrr€ViAfÏOIIS.2 Description of the problems.3 Research objective and methodology. ened ng TH ng ng TK tne ede e bee teens 4 1.1 Geological characteristics in Alberta oil sands.2 Athabasca oil sands.00 cee nnn 202000001 121 n1 nh bebe nh hy và 6 1.3 Cold Lake oil sands. c2 22000000001 212 bene bbe beet ee khen 7 1.4 Peace River oil sandS.

c0 000 2001 111 nnnn tbe t be ten bee ee nha 8 1.5 Lloydminster oil sands. c2 20222 nn nh ewes 8 1.6 A review of the development of thermal recovery technology. 2000020 nee b bbe b bebe e bends 9 1.2 Fast-SAGD technIque.3 Hybrid SAGD technique.5 The control of operating parameters under reservoir condifIons. Design of Experiment and Response Surface Methodology 2.1 Response surface methodologøy.2 Two-Level Factorial Designs.3 Two-Level Fractional Factorial Designs.4 Central Composite Design (CCT).5 Box-Behnken desIgn.

Face Centred Central Composite Design (FCCD). bn nee eben been bebe nh sa 24 2. Model adequacy checking.1 Test for significant Ofr€ØT©SSION. ene bebe bende bbb bebe eben sa28 2.

cnn e ebb eben nhe 29 2.4 Lack of Fit T€SẨ. L0 000020000212 212 eben deb ee tbe beeen ees 3] 2. 00000020 bn need bbb bb bbe ens 32 Chapter 3: Effects of Reservoir Properties and Operating Conditions on SAGD Performance 3.1 The application D-Optimal design and RMS for sensitivity analys1s.2 Effects of reservoir variables. nnn b nD ebb deeb bbe TK Ebner bene 38 3.

eee eee enn ed cee ĐT ĐT bee tne kh ấy 39 3. enn 212 nent dnb cent beet nh nh hấu 39 3. c7 20000002 bn bette bb bb bbe tebe been hy 40 3. 000000 En Een EEE bn nde bn ent bbb k beeen nở 40 3.6 Rock thermal conduCfIVIfV.

e kent een ne eben ene es Al 3.3 Effect of operational paramefters.1 Vertical well spacing (IPS). cece ence ence eben nh nhe 4] 3.2 Injection PT€SSUT€. 2020000002 bbb ng bbe been key 42 3.3 Steam Injection Rafe. n ne bbb ebb b eee ey 42 3.

ne nnn ebb ng ke sa 43 Chapter 4: Response Surface Optimization for Operating Conditions in Three Major Reservoirs of Alberta’s Oil Sand. eee tee c0 2n ng ng ng ng ky.1 Application of central composite face-centred design for optimizing the operating LO)0618 C0) 0 2.22000002002021 1211 n1 nn ng ng nh nàn nh thà và 52 4.2 Effect of operating parameters on the NPV.3 Optimization of operating conditions by response surface methodology.4 Verification of predictive model.00 00 ccc cence ence ence ee een teeny 57 4.5 Comparison and the best choice for operating conditions in conventional SAGD process 4.6 Optimization for Fast-SAGD performance.7 Optimization for discontinuous SAGD performance.2 Cold Lake oIlsands. c7 220000000212 212 n1 1 nh bebe ete: 64 4.1Application of Box-Behnken design for optimizing the operating conditions.2 Effect of operating parameters on the NPV.3 Optimization of operating conditions by response surface methodology.4 Verification of predictive model.5 Comparison and the best choice for operating conditions in conventional SAGD PTOCESS. nnn enon bebe tee tettttttttattetetttstetateeeeeee 1 OD 4.6 Optimization for Fast-SAGD performance.7 Optimization for discontinuous SAGD performance.3 Peace River oilsandsS.

nen cn nen ene nde bbe enn so 77 4.1 Application of central composite face-centred design for optimizing the operating.2 Effect of operating parameters on the NPV.3 Optimization of operating conditions by response surface methodology.4 Verification of predictive model.5 Comparison and the best choice for operating conditions in conventional SAGD process 4.6 Optimization for Fast-SAGD performance.7 Optimization for discontinuous SAGD performance. 85 Chapter 5: Summary, Conclusions and Recommendatfions. Een ebb bbe Eee ben nas 90 5. 22000000202 212 1 n1 denne etd e cde ede b dee teens 9] 5.3 Recommendations for future WOTK.

C2222 ete ene nhà. 93 References List of Figures 1. The regions of Albertan Oil Sands, cross section and stratigraphic succession, 2008, AAPG. Typical viscosities of bitumen in three majors oil sands 1.

The production mechanism of SAGD horizontal well pairs (NEB, 2004) 1. Operation of injection and production in SAGD process (NEB, 2004) 1. The Fast —SAGD process 1. Arrangement of wells in HSAGD and Fast-SAGD system 2.

Sample experimental designs (a) 2” factorial design, (b) 3Ý factorial design, (c) central composite design and (d) face-centred cubic design 2. The points distribution of a Central Composite Design 2.3 Box- Behnken design 2. Geometry of Face Centred Central Composite for three variables. Normal probability plot of residuals 2.

The desirability curve for the goal as minimum 2. The desirability curve for the goal as maximum 2. The desirability curve for the goal as maximum 2. The desirability curve for the goal as Within range 3.

The order ranking of variables 3. Normal probability plot of NPV response 3. Effects of reservoir and operational parameters on NPV responses 4. The order ranking of factors affecting on NPV, Athabasca oilsands 4.2 Effects of operating conditions on NPV, Athabasca oilsands 43 Response surface plots, Athabasca oilsands 4.

Cumulative oil in Athabasca oil sands 4. Cumulative SOR in Athabasca oil sands 4. Oil rates in Athabasca oil sands 4. The order ranking of factors affecting on NPV, Cold Lake Oilsands 4.

Effects of operating conditions on NPV, Cold Lake oilsands 4. Surface response map, Cold Lake oilsands 4. Optimal operating conditions of CSS well in Fast SAGD, Cold Lake oil sands 411. Response Surface plots in Fast-SAGD, Cold Lake oil sands 4.

Cumulative oil in Cold Lake 4. Cumulative steam oil rate in Cold Lake 4. Oil rate in Cold Lake 4. The order ranking of factors affecting on NPV, Peace River oilsands 4.

Effects of operating conditions on NPV, Peace River oilsands 4. Surface response map in SAGD process, Peace River oilsands 4. Optimal operating conditions of CSS well in Fast SAGD, Peace River oil sands 4. Response Surface plots in Fast-SAGD, Peace River oilsands 4.

Cumulative Oil in Peace River Oilsands 4. Cumulative SOR in Peace River Oilsands 4. Oil rates in Peace River Oilsands List of Tables 1.1 Geological features of Cold Lake in Alberta (National Energy Board, 2000) 2. Coded factor levels for Box-Behnken designs for optimizations involving four and five factors 2.2 Comparison of efficiency of central composite design and Box-Behnken design 3.

Variables and D-optimal design levels 3. The D-optimal design with 10 independent variables 3. ANOVA for response surface quadratic model 3. Regression coefficients of the predicted quadratic polynomial model.