Colloidal Dispersion Gels (CDG) and Their Application in Wyoming and Elsewhere E. Manrique & M. Lantz Jackson Hole, WY, September 12-13, 2011 The Science of Enhanced Oil Recovery The Science of Enhanced Oil Recovery
Outline • Introduction: • What are CDGs (Colloidal Dispersion Gels)? • CDG Development Review • Summary of EOR & CDG projects in Wyoming • Wyoming Tertiary Projects • CDG Experience in Wyoming • Recent Advances of Lab. & Simulation Studies • CDG Experiences Elsewhere • Field Experiences in Argentina and Colombia • Closing Remarks The Science of Enhanced Oil Recovery
Introduction: What are CDGs? • CDGs can be considered similar to polymer flooding • CDGs (weak gels) generate higher viscosities & RRF than polymer solutions at lower concentrations • HPAM are co-injected with Al-Citrate (crosslinker) - Viscosity/inj. pressure build-up (gelation/retention) • Very controversial topic! - However, some lab results do not support field performances The Science of Enhanced Oil Recovery
Introduction: CDG Development Review • Phillips Petroleum first developed the “layered process” which was first injected in 1980 in the North Burbank field - Found sequential injection of HPAM / aluminum citrate (AlCit) created higher RRF than straight polymer • In an effort to quickly test the layered process in the lab, TIORCO performed screen pack tests with mixed solutions of low concentrations of HPAM and AlCit • Found that the solution had no visible bulk gel characteristic; however, flow was notably retarded through the screen pack - Despite discrepancies of lab studies reported by different organizations over the years the CDG technology has shown a renewed interest at lab and field scale The Science of Enhanced Oil Recovery
Introduction: CDG Development Review (Cont’d) • The first CDG flood was implemented in 1985 in the Edsel Minnelusa Unit, Crook County, WY - The flood switched from the layered to the CDG process - Results showed an incremental recovery of 11.5 % OOIP • To date, over 70 CDG floods have been implemented in the U.S. and abroad The Science of Enhanced Oil Recovery
Summary of EOR & CDG Projects in Wyoming The Science of Enhanced Oil Recovery The Science of Enhanced Oil Recovery
Wyoming Tertiary Projects: 2008 Wyoming O&G Stats, The WOGCC • To date, 39 CDG floods have been completed in Wyoming ~42% of polymer floods are CDG floods The Science of Enhanced Oil Recovery
Evaluation of Chemical Flooding in the Minnelusa Formation, PRB, WY* • EORI publication evaluated the EUR of 32 chemical (mostly polymer) and waterfloods • The primary conclusions were: - Chemical flooding improves recovery by an average of 9% OOIP compared to waterflooding - Chemical flooding produces more oil sooner - The sooner you start EOR the more oil you recover *Thyne, G., Alvarado, V., Murrell, G., Evaluation of Chemical Flooding in the Minnelusa Formation, Powder River Basin, Wyoming. Search and Discovery , Article # 50239, February 26, 2010. The Science of Enhanced Oil Recovery
Minnelusa Production Analysis CDG or CDG + polymer floods (PF’s) reported as PF only ASP Courtesy of EORI The Science of Enhanced Oil Recovery
CDG Experience in Wyoming • Not all CDG projects in Wyoming (Mainly Minnelusa Fm.) were reported as successful (SPE-27780): Unsuccessful Projects Marginal Economics Swartz Draw, Campbell Co., 1987 Stewart Ranch, Campbell Co., 1985 Long Tree, Campbell Co., 1988 Pfieler Lease, Campbell Co., 1987 Bishop Ranch, Campbell Co., 1990 Spirit Field, Crook Co., 1993 Ottie Draw, Campbell Co., 1990 Wolf Draw, Crook Co., 1991 • There are successful and highly profitable projects too (>20) • In summary, CDG technology can fail as much as other EOR methods. However, not all unsuccessful projects are published or recognized The Science of Enhanced Oil Recovery
CDG Experience in Wyoming: N. Rainbow Ranch Unit (SPE-27773 Updates) • Summary of reservoir and fluid properties (R71W – T49N) Formation Minnelusa Depth 9,500 ft Porosity 19.7% Water Saturation 20% Temperature 202°F Permeability Range 1 - 1,000 mD Perm. Variation (DP) 0.9 26 ° API Oil Gravity Oil Viscosity 3.94 cP The Science of Enhanced Oil Recovery
CDG Experience in Wyoming (Cont’d) : N. Rainbow Ranch Unit (SPE-27773 Updates) • Summary of CDG treatment design: Injection Concentration Stage Product* Pounds mg / l bbls Cationic 1 81,000 22,000 775 Polymer Anionic 2 46,000 22,500 1,400 Polymer Anionic Polymer 83,100 1,200 3 198,000 Al-Citrate 71,000 1,000 Anionic Polymer 68,700 300 4 654,000 Al-Citrate 76,000 330 * Polyacrylamide polymers The Science of Enhanced Oil Recovery
CDG Experience in Wyoming (Cont’d) : N. Rainbow Ranch Unit (SPE-27773 Updates) CDG Performance (Oil rate vs. time) #6 Casing Collapse The Science of Enhanced Oil Recovery
CDG Experience in Wyoming (Cont’d) : N. Rainbow Ranch Unit (SPE-27773 Updates) 900 MBO Incremental The Science of Enhanced Oil Recovery
CDG Experience in Wyoming (Cont’d ) : N. Rainbow Ranch Unit Summary Conclusions • Approximately 12% PV was injected over the life of chemical flood • CDGs using high molecular weight polymer were successfully injected into a non-fractured, high permeability sandstone formation • Total recovery to date of 49.4% OOIP • Preliminary incremental recovery estimates were estimated in 8.0% of OOIP (SPE-27773). Current analysis suggests an incremental recovery of 15.7% OOIP • Updated results estimate a development cost of $1 per incremental barrel The Science of Enhanced Oil Recovery
Recent Advances in CDG Lab & Simulation Studies The Science of Enhanced Oil Recovery The Science of Enhanced Oil Recovery
CDG Technology: Laboratory Study Updates • CDG lab studies shows large discrepancies and different laboratory protocols • Recent studies in Canada, Norway and Colombia reported: − “CDG systems promote in-situ permeability reduction in unconsolidated high-permeability porous media as opposed to only the mobility control effect of polymer flooding” (CIPC 2009 -045) − “CDG propagates through water -wet Berea sandstone cores with no chromatographic separation “ (SPE -129927) − CDG injection in slim tubes showed PV reduction supported by tracer injection before and after treatment (Castro, R. MSc. Dissertation, UIS, Bucaramanga, Colombia, August 2011) • Since 2009 Tiorco started comprehensive lab and simulation studies as an effort to improve the understanding of CDG The Science of Enhanced Oil Recovery
CDG Technology: Laboratory Study Updates (Cont’d) Castro R., August 2011 Before CDG After CDG The Science of Enhanced Oil Recovery
CDG (20:1) vs. Polymer Flooding: 1ft Slim Tube Tests (~ 3 Darcy) 206,8 110,0 70,9 3,0 The Science of Enhanced Oil Recovery
CDG (20:1) vs. Polymer Flooding: 1ft Slim Tube Tests (~ 7 Darcy) 177,8 117,8 46 2,4 The Science of Enhanced Oil Recovery
CDG Technology: Simulation Updates (U.S. Pilot 2010-2011) • CDG pilot project (4 injectors) was presented showing a reasonably good history match using gel option • CDG predictions are in agreement with current oil production in the field • CDGs and polymer flooding generated similar incremental oil. However, CDGs required 40% less mass of polymer • Injection well pressures and/or oil recoveries can’t be properly match using skin factors • Tracer breakthrough (BT) times before and after CDG injection support changes in porous media (CDG delay tracer BT) • CDG injection of 0.2 PV was possible in a thin (25 ft) and low permeable (1-600 md) formation (8 cp crude oil) The Science of Enhanced Oil Recovery
CDG Experiences Elsewhere The Science of Enhanced Oil Recovery The Science of Enhanced Oil Recovery
CDG Experiences Elsewhere: Summary Review • An important number of CDG field tests have been documented in the literature − CDG field (29) projects review (SPE 20234 & 27780) − Adon Road (SPE-35352) and Lone Cedar (SPE-17539) − Daqing Field, China (SPE-62610) − Loma Alta Sur (SPE-113320) and El Tordillo (SPE-113334) Fields, Argentina − Dina Cretáceos, Colombia (SPE-139200) • Despite the number of field projects, not much effort has been dedicated to interpret/correlate lab. & field performance. However, there are ongoing efforts to evaluate past and current experiences The Science of Enhanced Oil Recovery
CDG Experiences Elsewhere: Summary Review (Cont’d) • As of today, there are several ongoing projects in Argentina (Confidential Client, 5 patterns), Colombia (Dina Field, 1 pattern) and the U.S. (4 projects, 1 to 4 patterns) − Based on advanced screening studies (Alvarado & Manrique, 2010; SPE-139200) have identified Minnelusa reservoirs as possible analogs of multiple Colombian reservoirs − Bracken, Candy Draw Unit and Rule Fields are few of the closer analogs to Dina Field in Colombia − Screening study contributed to justify CDG evaluation and field implementation based on field properties and project economics − Tiorco is also performing designs for projects scheduled 1Q and 2Q of 2012 in Canada, China and the U.S. including Wyoming The Science of Enhanced Oil Recovery
Recommend
More recommend
