Page 6 - Enhanced Oil Recovery in Shale and Tight Reservoirs

Contents

Acknowledgments ix

1. Introduction to shale and tight reservoirs 1
1.1 Introduction 1
1.2 Definitions of shale and tight reservoirs 2
1.3 Shale and tight resources 6
1.4 Current production technologies 6

2. Huff-n-puff gas injection in oil reservoirs 7
2.1 Introduction 7
2.2 Initial simulation studies of huff-n-puff gas injection 8
2.3 Experimental methods 9
2.4 Effect of core size 18
2.5 Effects of pressure and pressure depletion rate 20
2.6 Effect of soaking time 25
2.7 EOR performance with number of cycles 29
2.8 Effect of injected gas composition 31
2.9 Minimum miscible pressure 37
2.10 Effect of diffusion 41
2.11 Effect of water saturation 43
2.12 Effect of stress-dependent permeability 45
2.13 Huff-n-puff mechanisms 46
2.14 Gas penetration depth 51
2.15 Field projects 54

3. Asphaltene precipitation and deposition in a huff-n-puff process 61
3.1 Introduction 61
3.2 Experiments of asphaltene precipitation and permeability reduction 61
3.3 Deposition mechanisms 69
3.4 Numerical analysis 71
3.5 Effect of asphaltene deposition on huff-n-puff optimization 75

4. Huff-n-puff injection in shale gas condensate reservoirs 81
4.1 Introduction 81
4.2 Experimental setup 83
4.3 Huff-n-puff gas injection 84

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