American Oil and Gas Reporter - June 2012 - 98

SpecialReport: Artificial Lift Technology
move forward with a natural gas liquids extraction project, as well as make confident decisions about future CO2 purchase requirements. We are now fine tuning the model to use as a WAG optimization tool. Using the reservoir simulator along with flood monitoring tools provides a high degree of confidence in our daily management of this EOR project. Operational Obstacles A number of obstacles typical of CO2 floods were encountered, including accelerated scale and asphaltene formation. Although both were anticipated, asphaltene formation was encountered earlier and at greater deposition rates than expected. Two electrical submersible pumps plugged with asphaltene overnight, signaling that the problem was immediate and severe. Xylene was pumped down the tubing to clear the pumps, but the treatments were not completely successful and both pumps had to be pulled. Ultimately, asphaltene formation has been overcome by injecting an inhibitor down a second capillary string. Another major problem was corrosion caused by the formation of carbonic acid in the produced water. This was addressed by combining a corrosion inhibitor with the scale inhibitor injected at the pump intake. Corrosion inhibitor is also injected at the wellhead to protect the carbon steel flow lines. Producing wells were initially pumped with ESPs sized to maintain minimum fluid levels while the field was under waterflood. As CO2 production increased, the typical waterflood practice of minimizing bottom-hole pressure did not apply to a CO2 flood. The first pump failures indicated both up- and down-thrust wear on the stages. Some pumps also showed signs of overheating in some stages. These facts suggested there was a problem with slugs of gas blowing liquid out of the tubing, followed by occasional gas locking. Several mechanisms were employed to improve the situation. First, fluid levels were allowed to increase so the pump intake pressure would be high enough to keep the CO2 in its supercritical phase. Second, pump stages were chosen based on pump curves that displayed increasing head, and each pump was slightly overstaged so that it could clear a gas lock at the anticipated gas density. Finally, the variable speed drive (VSD) was programmed to recognize a drop in amperage, indicating the tubing was unloading. The VSD speeds the pump to increase the maximum head at the noflow condition and clear the gas lock. As amps increase, indicating liquid was again being pumped, the VSD slowly returns to its original speed. Four wells are now able to flow continuously with additional wells expected soon. To accommodate this change in producing conditions, a sliding sleeve installed above the ESP provides the flexibility to flow or pump the well by opening or closing the sleeve. If the well continues to flow, the pump is eventually pulled and a packer installed. The packers and capillary strings are configured so that chemical injection can continue at the tubing inlet. Ì Editor’s Note: Additional information on the Beaver Creek Madison CO2 project is available in SPE 152862, a technical paper prepared for presentation at the Society of Petroleum Engineers’ 2012 Improved Oil Symposium, held April 1418 in Tulsa. The preceding article was adapted from the paper.

Coming In July
Special Report: Horizontal & Innovative Drilling

CHARLES A. PETERSON is senior adviser, reservoir engineering, for Devon Energy Corporation in Oklahoma City. Peterson began his career in reservoir and operations engineering with Exxon in New Orleans, followed by serving as a district reservoir engineer with Texas Oil & Gas in Wichita, Ks. His nine-year association with TXO subsequently took him to South Texas for two years and to Oklahoma City in 1991 with Marathon Oil Company. After serving four years with Marathon and another four years as a reservoir engineer with SONAT Exploration, Peterson joined Devon Energy in 1998. He was on the team that identified and evaluated the Beaver Creek Madison CO2 flood. He holds a B.S in civil engineering from the University of Kansas. EDWARD J. PEARSON is operations engineering manager for Devon Energy Corporation in Oklahoma City. He was responsible for overseeing the Beaver Creek CO2 project facilities design
98 THE AMERICAN OIL & GAS REPORTER

and construction, well work and production operations after the flood was initiated. Prior to joining Devon, Pearson held a variety of positions with Mobil Oil and Citation Oil & Gas. He holds a B.S. in chemical engineering from the Georgia Institute of Technology VERONICA T. CHODUR is a senior reservoir engineer for Devon Energy in Oklahoma City. At present, she is prospecting and developing horizontal oil opportunities in the Powder River Basin. Chodur began her career as a production engineer with Chevron in West Texas fields, and then progressed to reservoir engineering, working the Mabee CO2 flood north of Midland, Tx. She joined Devon Energy in 2008 as a reservoir engineer working the Wind River and Big Horn Basins, including conventional and unconventional oil and gas, coalbed methane, and reservoir management of the Beaver Creek CO2 flood, where she and Devon’s CO2 team managed and oversaw an oil production

increase from 300 to more than 5,000 barrels a day. Chodur holds a B.S. in petroleum engineering from the University of Texas at Austin. CARLOS PEREIRA is president and founder of MI3 Petroleum Engineering Corporation. He was responsible for the reservoir modeling and flood design work on the Beaver Creek CO2 project. With 17 years of oil and gas experience working in North America, South America, Asia, the Middle East and Europe, his technical expertise is in practical and appropriate applications of existing technologies in primary, secondary and tertiary recovery. Pereira has experiences in unconventional and conventional resources, including CO2 miscible floods, nitrogen miscible floods, chemical flooding and thermal EOR processes. Pereira holds a B.S. in chemistry, an M.S. in integrated reservoir management and an M.S. in petroleum engineering from the Colorado School of Mines.



Table of Contents for the Digital Edition of American Oil and Gas Reporter - June 2012

American Oil and Gas Reporter - June 2012
Contents
Reports
Calendar
Oil & Gas Counts
State Legislative
Industry Digest
Natural Gas NSPS Affects a Variety of Equipment
Federal Legislation
SPCC
EPA
Keystone XL
Tech Connections
Washington Watch
Anadarko Finds World-Class Reservoirs in Deepwater Mozambique
Variety of Projects Have Permian Basin Hopping
Infrastructure Bottlenecks Easing in Permian Region
Completion Design Optimizes Yeso-San Andres Oil Wells
Cover Story
Beaver Creek CO2 Flood Boosts Madison Production
Study Evaluates Low-Salinity Waterfloods
Variable Speed Drives Coming of Age
Activity Spurring Artificial Lift Innovations
Project Shows STMZ’s Viability for Lower Tertiary Completions
ICDs, Modeling Improve Horizontal Shelf Well Completion
Intelligent Gas Lift Maximizes Production, Recovery
KOGA
CIPA
TOGA
TAEP
Frac Rules
Marcellus Regs
Conventions
The American Well Servicing Directory, Summer 2012
Industry Focus
Classified Advertising
Advertisers Index
American Oil and Gas Reporter - June 2012 - American Oil and Gas Reporter - June 2012
American Oil and Gas Reporter - June 2012 - Cover2
American Oil and Gas Reporter - June 2012 - Contents
American Oil and Gas Reporter - June 2012 - Reports
American Oil and Gas Reporter - June 2012 - 5
American Oil and Gas Reporter - June 2012 - 6
American Oil and Gas Reporter - June 2012 - 7
American Oil and Gas Reporter - June 2012 - Calendar
American Oil and Gas Reporter - June 2012 - 9
American Oil and Gas Reporter - June 2012 - 10
American Oil and Gas Reporter - June 2012 - 11
American Oil and Gas Reporter - June 2012 - 12
American Oil and Gas Reporter - June 2012 - 13
American Oil and Gas Reporter - June 2012 - Oil & Gas Counts
American Oil and Gas Reporter - June 2012 - 15
American Oil and Gas Reporter - June 2012 - Industry Digest
American Oil and Gas Reporter - June 2012 - 17
American Oil and Gas Reporter - June 2012 - 18
American Oil and Gas Reporter - June 2012 - 19
American Oil and Gas Reporter - June 2012 - 20
American Oil and Gas Reporter - June 2012 - 21
American Oil and Gas Reporter - June 2012 - 22
American Oil and Gas Reporter - June 2012 - 23
American Oil and Gas Reporter - June 2012 - Natural Gas NSPS Affects a Variety of Equipment
American Oil and Gas Reporter - June 2012 - 25
American Oil and Gas Reporter - June 2012 - 26
American Oil and Gas Reporter - June 2012 - 27
American Oil and Gas Reporter - June 2012 - Federal Legislation
American Oil and Gas Reporter - June 2012 - 29
American Oil and Gas Reporter - June 2012 - 30
American Oil and Gas Reporter - June 2012 - 31
American Oil and Gas Reporter - June 2012 - SPCC
American Oil and Gas Reporter - June 2012 - 33
American Oil and Gas Reporter - June 2012 - Keystone XL
American Oil and Gas Reporter - June 2012 - 35
American Oil and Gas Reporter - June 2012 - 36
American Oil and Gas Reporter - June 2012 - Tech Connections
American Oil and Gas Reporter - June 2012 - 38
American Oil and Gas Reporter - June 2012 - Washington Watch
American Oil and Gas Reporter - June 2012 - Anadarko Finds World-Class Reservoirs in Deepwater Mozambique
American Oil and Gas Reporter - June 2012 - 41
American Oil and Gas Reporter - June 2012 - 42
American Oil and Gas Reporter - June 2012 - 43
American Oil and Gas Reporter - June 2012 - 44
American Oil and Gas Reporter - June 2012 - 45
American Oil and Gas Reporter - June 2012 - 46
American Oil and Gas Reporter - June 2012 - 47
American Oil and Gas Reporter - June 2012 - 48
American Oil and Gas Reporter - June 2012 - 49
American Oil and Gas Reporter - June 2012 - Variety of Projects Have Permian Basin Hopping
American Oil and Gas Reporter - June 2012 - 51
American Oil and Gas Reporter - June 2012 - 52
American Oil and Gas Reporter - June 2012 - 53
American Oil and Gas Reporter - June 2012 - 54
American Oil and Gas Reporter - June 2012 - 55
American Oil and Gas Reporter - June 2012 - 56
American Oil and Gas Reporter - June 2012 - 57
American Oil and Gas Reporter - June 2012 - 58
American Oil and Gas Reporter - June 2012 - 59
American Oil and Gas Reporter - June 2012 - 60
American Oil and Gas Reporter - June 2012 - 61
American Oil and Gas Reporter - June 2012 - 62
American Oil and Gas Reporter - June 2012 - 63
American Oil and Gas Reporter - June 2012 - Infrastructure Bottlenecks Easing in Permian Region
American Oil and Gas Reporter - June 2012 - 65
American Oil and Gas Reporter - June 2012 - 66
American Oil and Gas Reporter - June 2012 - 67
American Oil and Gas Reporter - June 2012 - 68
American Oil and Gas Reporter - June 2012 - 69
American Oil and Gas Reporter - June 2012 - 70
American Oil and Gas Reporter - June 2012 - 71
American Oil and Gas Reporter - June 2012 - Completion Design Optimizes Yeso-San Andres Oil Wells
American Oil and Gas Reporter - June 2012 - 73
American Oil and Gas Reporter - June 2012 - 74
American Oil and Gas Reporter - June 2012 - 75
American Oil and Gas Reporter - June 2012 - 76
American Oil and Gas Reporter - June 2012 - 77
American Oil and Gas Reporter - June 2012 - 78
American Oil and Gas Reporter - June 2012 - 79
American Oil and Gas Reporter - June 2012 - 80
American Oil and Gas Reporter - June 2012 - 81
American Oil and Gas Reporter - June 2012 - Cover Story
American Oil and Gas Reporter - June 2012 - 83
American Oil and Gas Reporter - June 2012 - 84
American Oil and Gas Reporter - June 2012 - 85
American Oil and Gas Reporter - June 2012 - 86
American Oil and Gas Reporter - June 2012 - 87
American Oil and Gas Reporter - June 2012 - 88
American Oil and Gas Reporter - June 2012 - 89
American Oil and Gas Reporter - June 2012 - 90
American Oil and Gas Reporter - June 2012 - 91
American Oil and Gas Reporter - June 2012 - Beaver Creek CO2 Flood Boosts Madison Production
American Oil and Gas Reporter - June 2012 - 93
American Oil and Gas Reporter - June 2012 - 94
American Oil and Gas Reporter - June 2012 - 95
American Oil and Gas Reporter - June 2012 - 96
American Oil and Gas Reporter - June 2012 - 97
American Oil and Gas Reporter - June 2012 - 98
American Oil and Gas Reporter - June 2012 - 99
American Oil and Gas Reporter - June 2012 - Study Evaluates Low-Salinity Waterfloods
American Oil and Gas Reporter - June 2012 - 101
American Oil and Gas Reporter - June 2012 - 102
American Oil and Gas Reporter - June 2012 - 103
American Oil and Gas Reporter - June 2012 - Variable Speed Drives Coming of Age
American Oil and Gas Reporter - June 2012 - 105
American Oil and Gas Reporter - June 2012 - 106
American Oil and Gas Reporter - June 2012 - 107
American Oil and Gas Reporter - June 2012 - Activity Spurring Artificial Lift Innovations
American Oil and Gas Reporter - June 2012 - 109
American Oil and Gas Reporter - June 2012 - 110
American Oil and Gas Reporter - June 2012 - 111
American Oil and Gas Reporter - June 2012 - 112
American Oil and Gas Reporter - June 2012 - 113
American Oil and Gas Reporter - June 2012 - 114
American Oil and Gas Reporter - June 2012 - 115
American Oil and Gas Reporter - June 2012 - 116
American Oil and Gas Reporter - June 2012 - 117
American Oil and Gas Reporter - June 2012 - Project Shows STMZ’s Viability for Lower Tertiary Completions
American Oil and Gas Reporter - June 2012 - 119
American Oil and Gas Reporter - June 2012 - 120
American Oil and Gas Reporter - June 2012 - 121
American Oil and Gas Reporter - June 2012 - 122
American Oil and Gas Reporter - June 2012 - 123
American Oil and Gas Reporter - June 2012 - 124
American Oil and Gas Reporter - June 2012 - 125
American Oil and Gas Reporter - June 2012 - 126
American Oil and Gas Reporter - June 2012 - 127
American Oil and Gas Reporter - June 2012 - 128
American Oil and Gas Reporter - June 2012 - 129
American Oil and Gas Reporter - June 2012 - 130
American Oil and Gas Reporter - June 2012 - ICDs, Modeling Improve Horizontal Shelf Well Completion
American Oil and Gas Reporter - June 2012 - 132
American Oil and Gas Reporter - June 2012 - 133
American Oil and Gas Reporter - June 2012 - 134
American Oil and Gas Reporter - June 2012 - 135
American Oil and Gas Reporter - June 2012 - 136
American Oil and Gas Reporter - June 2012 - 137
American Oil and Gas Reporter - June 2012 - 138
American Oil and Gas Reporter - June 2012 - 139
American Oil and Gas Reporter - June 2012 - 140
American Oil and Gas Reporter - June 2012 - Intelligent Gas Lift Maximizes Production, Recovery
American Oil and Gas Reporter - June 2012 - 142
American Oil and Gas Reporter - June 2012 - 143
American Oil and Gas Reporter - June 2012 - 144
American Oil and Gas Reporter - June 2012 - 145
American Oil and Gas Reporter - June 2012 - 146
American Oil and Gas Reporter - June 2012 - 147
American Oil and Gas Reporter - June 2012 - 148
American Oil and Gas Reporter - June 2012 - KOGA
American Oil and Gas Reporter - June 2012 - 150
American Oil and Gas Reporter - June 2012 - 151
American Oil and Gas Reporter - June 2012 - CIPA
American Oil and Gas Reporter - June 2012 - 153
American Oil and Gas Reporter - June 2012 - 154
American Oil and Gas Reporter - June 2012 - 155
American Oil and Gas Reporter - June 2012 - TOGA
American Oil and Gas Reporter - June 2012 - 157
American Oil and Gas Reporter - June 2012 - 158
American Oil and Gas Reporter - June 2012 - 159
American Oil and Gas Reporter - June 2012 - 160
American Oil and Gas Reporter - June 2012 - 161
American Oil and Gas Reporter - June 2012 - 162
American Oil and Gas Reporter - June 2012 - 163
American Oil and Gas Reporter - June 2012 - TAEP
American Oil and Gas Reporter - June 2012 - 165
American Oil and Gas Reporter - June 2012 - 166
American Oil and Gas Reporter - June 2012 - 167
American Oil and Gas Reporter - June 2012 - 168
American Oil and Gas Reporter - June 2012 - 169
American Oil and Gas Reporter - June 2012 - 170
American Oil and Gas Reporter - June 2012 - Frac Rules
American Oil and Gas Reporter - June 2012 - Marcellus Regs
American Oil and Gas Reporter - June 2012 - 173
American Oil and Gas Reporter - June 2012 - Conventions
American Oil and Gas Reporter - June 2012 - The American Well Servicing Directory, Summer 2012
American Oil and Gas Reporter - June 2012 - 176
American Oil and Gas Reporter - June 2012 - 177
American Oil and Gas Reporter - June 2012 - 178
American Oil and Gas Reporter - June 2012 - 179
American Oil and Gas Reporter - June 2012 - 180
American Oil and Gas Reporter - June 2012 - 181
American Oil and Gas Reporter - June 2012 - 182
American Oil and Gas Reporter - June 2012 - 183
American Oil and Gas Reporter - June 2012 - 184
American Oil and Gas Reporter - June 2012 - 185
American Oil and Gas Reporter - June 2012 - 186
American Oil and Gas Reporter - June 2012 - 187
American Oil and Gas Reporter - June 2012 - 188
American Oil and Gas Reporter - June 2012 - 189
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American Oil and Gas Reporter - June 2012 - 192
American Oil and Gas Reporter - June 2012 - 193
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American Oil and Gas Reporter - June 2012 - 196
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American Oil and Gas Reporter - June 2012 - 198
American Oil and Gas Reporter - June 2012 - 199
American Oil and Gas Reporter - June 2012 - 200
American Oil and Gas Reporter - June 2012 - 201
American Oil and Gas Reporter - June 2012 - 202
American Oil and Gas Reporter - June 2012 - Industry Focus
American Oil and Gas Reporter - June 2012 - 204
American Oil and Gas Reporter - June 2012 - 205
American Oil and Gas Reporter - June 2012 - 206
American Oil and Gas Reporter - June 2012 - 207
American Oil and Gas Reporter - June 2012 - 208
American Oil and Gas Reporter - June 2012 - Classified Advertising
American Oil and Gas Reporter - June 2012 - Advertisers Index
American Oil and Gas Reporter - June 2012 - Cover3
American Oil and Gas Reporter - June 2012 - Cover4
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