American Oil and Gas Reporter - June 2012 - 141

SpecialReport: Offshore & Subsea Technology

Intelligent Gas Lift Optimizes Recovery
By Ian Anderson CAMBRIDGE, U.K.–With global oil and natural gas demand outstripping supply and new discoveries lagging behind, despite the rise in shale gas production and the increasing number of new well permits being granted in the Gulf of Mexico, U.S. operators are looking to innovative technologies to maximize production and increase recovery rates from existing fields. This need to squeeze more from existing assets is exacerbated as a result of federal areas, such as the Pacific and Atlantic oceans, being off limits to new offshore oil and gas projects, and offshore progress in state waters beyond the Gulf of Mexico limited to certain areas of Alaska until 2017. Yet while regions of the world such as Norway and the Middle East are seeing real improvements in recovery (some parts of the North Sea’s Norwegian Continental Shelf are seeing recovery rates of up to 60 percent), this trend is not always reflected worldwide. Artificial lift is a key means of improving recovery rates and production, and continues to represent a growing market. Industry statistics show that more than 90 percent of the world’s producing wells utilize some form of artificial lift technology. Furthermore, of the 1.48 million oil-producing wells worldwide, only 30,000 are estimated to be free flowing. Artificial lift is on the rise in offshore fields in the Gulf of Mexico, such as the Amberjack oil field in the Mississippi Canyon block, through to onshore fields in Texas and Louisiana, where there is lower permeability, and in shale gas and tight oil plays, where production can decline by 70 percent or more in the first year of production. One technology that is gaining particular attention is gas lift, a technology that has seen significant advances over the past few years. In gas lift, natural gas, nitrogen or other gases are injected into the production tubing to reduce the impact of hydrostatic pressure. By reducing the density of the produced fluid column and drawing down flowing bottom-hole pressure, reservoir liquids enter the well bore at higher flow rates, thereby improving well performance and increasing recovery. Rick Lemanczyk, principal petroleum engineer at Senergy International and a 2011 Society of Petroleum Engineers distinguished lecturer on production optimization, estimates that gas lift-enabled fields can lead to a 2-5 percent increase in fieldwide production and have a significant impact on recovery rates. Attractive Characteristics Gas lift has a number of characteristics that are particularly attractive to operators, including: • The ability to handle gassy, sandy and corrosive fluids in deviated wells; • Applicability to a wide range of production rates and well conditions; and • Side pocket mandrel and gas lift injection valves, which allow deeper gas injection in the tubing. Side pocket mandrels, however, come with limitations as well. They require wireline intervention to change injection depth and make significant rate changes possible. They also provide little information on pressures and temperatures at the point of gas injection, and limited control and flexibility over altering injection rates in real time. The dangers of intervention were highlighted in an incident in the Norwegian North Sea last year when replacing a gas lift valve led to a separate piece of equipment becoming stuck, leaving only one barrier in the well to prevent an oil spill. The incident was highlighted by Norway’s Petroleum Safety Authority, which issued an enforcement notice to the operator. As well as the concerns over wireline intervention, the temperature sensitive “injection pressure-operated” devices or simple orifices with fixed port sizes that side pocket mandrels host are vulnerable to unstable operation when annulus and/or tubing pressures change. This can lead to gas injection at the wrong point and potential valve failure, since most unloading valves are not designed for continuous injection. At a time of fluctuating field conditions, such as increased water and gas breakthroughs in wells, fluctuating flow rates, and decreasing liquid rates in many older fields, many of today’s gas lift solutions simply lack the necessary flexibility. It is this lack of flexibility in gas lift operations that requires operators to depend on certain assumptions about the field conditions in which gas lift will operate, and which then subsequently determine the gas lift design. For example, operators have to make an assumption that the well will operate at a particular reservoir pressure, and flow at a particular rate with a specific water cut. Intelligent Gas Lift Such assumptions, however, are not feasible because conditions inevitably change–sometimes rapidly–over the life of a well. This lack of information, difficulties over intervention, and reservoir assumptions can actually exacerbate well instability, leading to surges in liquid and gas flows that can shut down production separators, degrade field production uptime, and damage casing and tubing integrity. These challenges and limitations of conventional gas lift systems are being overcome through a new generation of intelligent, real-time digital gas injection technology that is installed within the production tubing to eliminate the need to use side pocket mandrels, wireline retrieval or any well intervention techniques to make changes to the gas injection rates to maintain efficient production. The technology introduces management and operational advantages far beyond the capabilities of existing solutions, enabling operators to vary injection rates and depth in real time without interrupting production, and generates pressure and temperature information throughout the gas injection process. This eliminates the need for side pocket mandrels and wireline intervention, with settings tuned as well bore conditions change throughout the life of the installation, giving greater downhole control of gas usage and preventing well instability problems. The digital gas lift method will soon to be deployed in an onshore well in Oman as part of a normal workover program for a high-productivity well to improve production performance. Although a test installation, intelligent gas lift equipment has been selected as the chosen method to lift this well. Simulation Analysis A simulation modeling analysis conducted by Laing Engineering & Training Services compared the performance of a standard, multimandrel gas lift design with a digital artificial lift solution. The
JUNE 2012 141



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
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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
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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
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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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