FUSION Technology: increasing production and ultimate recovery rates with advanced proppant pack consolidation technology

Transcription

1 WHITE PAPER FUSION Technology: increasing production and ultimate recovery rates with advanced proppant pack consolidation technology Author: Daryl Johnson, CARBO

2 FUSION TECHNOLOGY: INCREASING PRODUCTION AND ULTIMATE RECOVERY RATES WITH ADVANCED PROPPANT PACK CONSOLIDATION TECHNOLOGY INTRODUCTION Operators that have been producing from wells in the deepwater Gulf of Mexico (GOM) for many years will eventually require intervention to re-pressurize the reservoir in order to maintain an economic production rate. After establishing water injection wells to aid with production, the operator can often find that the reservoir pressure depletion is at a level where they need to inject at rates two to three times the level at which they have been producing. With well depths of 15,000 21,000 ft, operators can expect to see injection rate requirements in excess of 20,000 50,000 bbls a day. During Cased Hole Frac & Pack (CHFP) stimulation, proppant fills the wings of the fracture, then the annulus between the casing and the screen. The annular pack provides a secondary barrier for sand control. With conventional proppant, over time, the ultra-high injection rates or the pressure surges caused by Emergency Shut Downs (ESD) can cause the proppant in the fracture and annulus to become mobile. Under these conditions, proppant eventually washes out of the annulus, creating voids and allowing the ingress of formation fines. Crossflow during shut-in can create voids in the annular pack as well. Finally, the connection to the fracture can be lost and the pressure needed to inject at the required rates becomes so high as to make injection economically unviable. E&P operators facing these scenarios are required to limit water injection rates to protect the integrity of the annular pack, propped fracture and safeguard the well. THE QUEST FOR AN IMMOBILE PROPPANT With the objective to inject and produce at ultra-high rates for many years, two major operators approached CARBO to develop a new type of immobile proppant that would bond the highly conductive proppant pack in the formation and the annulus with or without closure stress, in order to deliver enhanced reservoir recovery in soft, unconsolidated formations. CARBO already had CARBOBOND technology for resin coating proppant that would bond together under the closure stress within a fracture. However, in the annulus, no closure stress exists to facilitate this type of bonding. Therefore, the challenge was to design a new immobile proppant system that would bond together without any closure stress with the aim of protecting the annular pack from formation fines migration, maintaining the connection to the fracture and preventing the pack in the formation from being destroyed. Twenty-nine different products and technologies were tested before one technology passed all of the rigorous immobile proppant screening tests and was successfully deployed in the field. 1

3 THE EVOLUTION OF FUSION TECHNOLOGY In order to address the challenges set by the operators, CARBO developed a fusion of four distinct technologies. High conductivity, high durability ceramic proppant was coated with an enhanced, proprietary resin coating that enabled controlled bonding of the proppant pack. A specially formulated chemical activator was developed that would, crucially, enable the resin coating to bond in noncompressive and low-temperature environments (in the annulus as well as in the fracture), creating a high integrity pack that withstands stress cycling while sustaining long-term pack integrity. As the FUSION coating also bonds with closure stress, it safeguards the integrity of the proppant pack in the fracture. The bonded proppant in the fracture helps minimize embedment in the formation face, prevent prop pack rearrangement and lowers the delta P across the pack. Operationally, it allows for a single resin-coated proppant and liquid additive to be used simultaneously in a continuous frac and pack operation. As the unique bonding process is chemically and temperature activated, any excess proppant in the workstring can be reversed out prior to the bonding of the proppant pack. The proppant will begin bonding in a matter of hours and is typically at maximum strength within hours. Fluid compatibility with linear HEC and Guar Borate x-linked frac fluids was maintained. CARBONRT, a non-radioactive tracer is manufactured into all of the base proppant to allow proppant detection throughout the completion system. The integration of these advanced CARBO technologies results in the unique FUSION solution for prop pack consolidation in deepwater, high-rate injectors and producers. FUSION creates a highly conductive and permanent proppant pack system to deliver enhanced injection and production rates resulting in additional reserves recovery. 2

4 FEATURES OF THE NON-RADIOACTIVE TRACER With the inclusion of CARBONRT technology, CARBO developed a proprietary method to determine not only the height of the propped fracture, but also the quality of the annular pack in order to determine the existence and position of any voids in the pack. During the manufacture of the ceramic proppant, a small amount of an inert, non-radioactive tracer is added to the mix and incorporated into the ore used to form each pellet. CARBONRT is detected downhole by Pulsed or Compensated Neutron wireline tools and then interpreted at the surface. Traditional radioactive tracers have a half-life, meaning that within six months they are typically below detectable levels. Because CARBONRT does not rely on radiation to be detected, it is permanently detectable. Operators can return time and again to re-log the well and determine annular pack integrity (including the creation of voids), near wellbore connectivity and propped fracture pack height for the entire life of the well. Additionally, its truly non-radioactive status means that the proppant can be transported and used internationally without being subject to a burdensome permitting process. 3

5 DEPLOYMENT OF FUSION FUSION technology has been successfully deployed by a group of major operators in three water injection wells. One on land in South Texas and two in the deepwater Gulf of Mexico. After putting 30 different potential immobile proppant products and technologies through the hurdle, validation and deployment tests during the three-year qualification program, the operators ultimately selected FUSION as the best solution to carry forward into the field trials. Well #1 A land based injection well was completed with exactly the same stimulation and sand control completion system as the future deepwater offshore GOM wells. After the successful placement of the FUSION proppant system, the injection rate has been greater than 30,000 bbls of water a day. In the first five months of injection, the total water volume was almost 1.5 million barrels. This well has been logged numerous times to evaluate whether the pack has changed or eroded. To date, the proppant pack has not changed. Well #2 A deepwater injection well in the GOM was successfully completed using FUSION proppant system. The well has been on production for over one year with injection rates up to 50,000 bwpd. Well #3 A deepwater injection well in the GOM was successfully completed using FUSION proppant system. The well has been on production for nine months with injection rates up to 22,000 bwpd. Note: All three wells have injected water at rates that exceed the fracturing pressure for their respective formations. 4

6 APPLICATIONS FUSION can be utilized in water injectors (and producers), in unconsolidated formations and soft sands where cased-hole frac pack completions for stimulation and sand control are used. Additional applications for gravel pack consolidation, formation stabilization, screenless frac-packs, proppant fracs on oil/natural gas and CO2 storage facility wells and steam flood injectors/producers are being explored. Because FUSION technology works without closure stress, it has many more opportunities to be the solution. CONCLUSION Previous frac and pack technologies for sand control are prone to integrity and stability issues that negatively impact injection or production and ultimately recovery. FUSION creates a unique, robust, cost-effective and commercially viable proppant technology for stimulation and sand control for injectors and producers. The integration of advanced technologies to create the FUSION system provides operators with the proppant pack integrity critical to being able to inject and produce at the ultra-high rates required to improve well economics, and increase ROI and EUR. TECHNICAL REFERENCE SPE MS September 2016 SPE Deepwater Completions Conference The Development and Qualification of a Novel Proppant System to Enhance Performance of High Rate Soft Sand Water Injection Wells With Cased Hole Sand Control Completions 5

7 CARBO is an industry leading production enhancement company that integrates technologies and intellectual capital to design, build and optimize fractures. FOR MORE INFORMATION To learn more about how our production assurance specialists can help you prevent flow assurance problems and enhance your production contact CARBO at carboceramics.com Our products and services enable clients to increase production and recovery for the life of the well by identifying the optimal balance of contact and conductivity for the reservoir, and building it efficiently to lower total finding and development costs per BOE. carboceramics.com 2017 CARBO Ceramics Inc. All Rights Reserved.