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August 2, 2013 - Project operations are complete.
Read the Final Project Technical Report
February 19, 2013 - Data from the 2011/2012 field test is now available!
Status Report - May 7, 2012
Final abandonment of Ignik Sikumi #1 wellsite has been completed. Tubing, casing-tubing annulus, and flatpack were filled with cement per the abandonment procedure approved by the Alaska Oil and Gas Conservation Commission. To minimize effects on the landscape and leave as little trace of the operations as possible, a small area around the wellhead was excavated to expose well casing to six feet below tundra surface. The tubulars were cutoff three feet below ground level. Cement fillup was verified, and a cap was welded on top. The excavation was refilled and graded appropriately to ensure original grade is achieved as temperatures rise and the ground settles with the change of the seasons. The top surface of the icepad was scraped, with residue hauled-off for disposal. Barriers to the pad entrance were erected and periodic monitoring during spring melt will continue.
Status Report - April 16, 2012
CO2/CH4 exchange and drawdown/ depressurization operations have been completed at Ignik Sikumi #1. Jetpump power fluid, consisting of heated formation water, was replaced in the annulus and tubing with heated glycol to freeze-protect the wellbore while surface injection and production equipment was moved off location. Jetpump retrieval via slickline is underway, and plugging of tubing and annulus with cement will follow. Once the wellbore is completely cemented, the casing and tubing will be cut off and capped at least three feet below the original tundra surface, resulting in permanent abandonment. Following removal of camp facilities, the icepad surface will be scraped, with scrapings hauled to subsurface disposal facility. Pad access will be closed-off, allowing pad to melt with spring warming.
Status Report - April 9, 2012
Jetpump-assisted drawdown operations at Ignik Sikumi #1 are entering their sixth and final week. Produced formation water is being heated and recycled as jetpump powerfluid. Stable gas and water production have continued, rates have increased slightly as bottomhole pressure has been lowered, and downhole freezing has been avoided. Produced gas volumes have been measured, after separation from power fluid and produced fluid, by flowmeters in the Low-flow Gas Measurement Skid. Compositional analysis of methane, nitrogen, carbon dioxide, and tracers pumped during injection are being monitored continuously by gas chromatograph in the Gas Mixing Skid. Produced water rate and total water salinity and solids content are monitored twice hourly.
Status Report - April 2, 2012
Jetpump-assisted drawdown operations at Ignik Sikumi #1 are entering their fifth week. Gas and water production have stabilized and production of formation fines has diminished greatly. Operations have transitioned from recovery of exchange products to depressurization below methane hydrate stability pressure. Precise manipulation of surface operating conditions has allowed for continued drawdown of reservoir pressure. Surface readout of three downhole pressure gauges facilitates accurate interpolation of reservoir conditions.
Maintaining continuous operations while gradually drawing-down reservoir pressure is the primary objective of the current phase. At the same time, avoiding downhole freezing is a critical operation goal. Depressurization leads to gas expansion, which causes cold produced fluids to cool even further. Downhole freezing has been avoided by continuously monitoring distributed temperature sensors in the fiber-optic DTS cable that provides temperature measurements along the entire wellbore every two minutes. Once target minimum operating temperature of 34° was reached, operating conditions were managed to maintain nearly constant bottomhole pressure.
Status Report - March 26, 2012
Jetpump-assisted drawdown operations continue at Ignik Sikumi #1. Changout of downhole reverse jetpump, performed with multiple slickline runs and a lubricator to manage wellhead pressure, was completed March 22. Critical design parameters for reverse jetpumping, specifically the jetpump throat and nozzle diameters, have been optimized for current operating (pressure and flowrate) conditions. This new pump has facilitated more profound lowering of reservoir pressure (drawdown) than the previous design. Gas production has been re-established following jetpump replacement.
Careful measurement of produced water and gases (methane, nitrogen, carbon dioxide, and tracers) has allowed periodic comparisons to predicted performance. Results to-date are within the broad range of pre-test predictions, which were based on in-house reservoir simulations.
Status Report - March 19, 2012
Flowback/drawdown operations continue at Ignik Sikumi #1. Jetpump-assisted flowing conditions were established March 7 and have continued since then. Production of small but variable amounts of very fine formation sand have caused minor operational interruptions. Downhole screens, installed across the perforations, have successfully mitigated sand control issues for coarser material, but screens are designed to allow passage and subsequent pumping to the surface of very fine material. Sand in the surface equipment can make separation of produced gases from water less efficient.
The best production rates have occurred most recently. Careful measurement of the relative abundances of injected carbon dioxide, nitrogen, and tracers versus produced methane and water will allow for quantification of CO2/CH4 exchange.
Status Report - March 12, 2012
Post-injection flowback has been underway at Ignik Sikumi #1 for just over one week. Unassisted flowback, in which wellbore fluids flowed to the surface without artificial lift, lasted for approximately 33 hours. When sufficient produced water had filled the tubing to balance reservoir pressure, unassisted flow ceased. Surface equipment was reconfigured for reverse jet pumping, including replacement of heated glycol in the upper annulus with warm water. A jet pump was run into the tubing on slickline, seated opposite a gas-lift mandrel. A gas-lift mandrel and nipples for landing the jet pump were installed in the upper completion in April, 2011 in expectation of jet pumping. To affect reverse jet pumping, a power fluid is pumped down the annulus, through the gas-lift mandrel and into the jet pump, located inside the tubing. A nozzle in the jet pump re-directs the power fluid upward through a venturi at a sufficiently high velocity that the venturi effect, which creates a lower pressure, allows greater inflow of formation fluids. The power fluid and produced fluid are pumped together to the surface, where water and gas are separated and measured.
Reverse jet pumping has been underway for less than one week. Methane was produced immediately, increasing in abundance for two days, then produced-gas composition stabilized. Carbon dioxide and nitrogen abundance dropped from injection percentages at initial flowback to relatively low percentages in a less than two days. Very fine-grained sand from the producing formation is also flowing into the wellbore, and solids are being settled-out tanks at the surface.
Status Report - March 5, 2012
Injection of mixed CO2/N2 gas at Ignik Sikumi #1 was completed February 28. Approximately 210,000 standard cubic feet (scf) of gas blend was injected into the hydrate-bearing Sagavanirktok "C" sandstone. Initial injection rate was ~11,000 scf per day, and gradually increased to ~21,000 scf per day during thirteen days of injection. Stable injection rates were maintained by recirculating non-injected CO2 and N2 through on-site tanks.
Upon completion of injection, the well was shut-in and surface equipment re-configured for flowback and drawdown testing. Three major reconfiguration steps were completed prior to initiation of flowback. First, flowlines were pressure-tested. Flowlines extend from the wellhead to a separator and the Low Gas Measurement Skid ("LGMS"), which will separate and measure produced liquids and gases. Flowlines also extend from the separator/LGMS to the flare stack, which will incinerate produced methane after measurement. Second, circulation of heated fluid in the upper annulus, to prevent hydrate re-formation in the production tubing was re-established. Finally, fresh-water for artificial lift of produced fluids was offloaded into upright tanks, which are being heated indirectly by glycol circulation. As of Monday morning, March 5, flowback had been underway for about 18 hours.
Status Report - Feb 27, 2012
Injection has been underway at Ignik Sikumi #1 for twelve days, and over 190,000 scf (standard cubic feet) of mixed CO2/N2 gas have been injected. The specific gas mixture was chosen, after reservoir simulation, based on two complementary criteria. First, modeling indicates that nitrogen alone will cause methane-hydrate dissociation, which would be accompanied by a lowering of reservoir temperature. Ambient reservoir temperature is just 41°F, and it is essential to maintain reservoir temperature above the freezing point of water. Second, if reactive water is present in the reservoir, an overabundance of carbon dioxide could lead to formation of secondary CO2-hydrate in the reservoir. Secondary CO2-hydrate formation provides less carbon dioxide for exchange and may also lower reservoir permeability. Nitrogen and carbon dioxide are blended in the Gas Mixing Skid into a mixture that most effectively minimizes CH4-hydrate dissociation and secondary CO2-hydrate formation.
Injection rate has slowly increased to approximately 20,000 scf per day, and injection is expected to continue until early this week. Upon completion of injection, wellbore, flowlines and other surface equipment will be re-configured for flowback.
Status Report - Feb 20, 2012
Carbon dioxide injection has begun and is proceeding as expected at Ignik Sikumi #1. Before injection could begin it was necessary to connect the wellbore to the formation by perforating through the well casing. Perforations had to be oriented to avoid the downhole cables installed to monitor temperature and pressure during the test. This was successfully accomplished with an oriented perforating tool that was mechanically rotated away from the cables. The wellbore was filled with a mixture of nitrogen and carbon dioxide gas while perforating, so injection began as soon as the perforations were made. Since perforation, sand screens have been installed opposite the perforations to inhibit flow of sand from the unconsolidated reservoir formation into the wellbore. Produced sand can inhibit efficient flow i the wellbore. Injection will to continue for approximately two weeks.
Status Report - Feb 13, 2012
Ignik Sikumi #1 is prepared for perforation and injection is imminent. Three major accomplishments occurred in the last week. First, following marine transport from the Seattle area and highway transport over the Alaska Range and Brooks Range, twenty-two tons of liquid carbon dioxide were delivered to Ignik Sikumi #1 well site and offloaded into a storage vessel. Second, utilizing a single continuous strand of coiled tubing that reached to the bottom of the well at a depth of 2371 feet, corrosion-inhibited and freeze-protected fluids, which at were intentionally left in Ignik Sikumi #1 since last winter, were sequentially displaced with warm seawater, nitrogen, and ultimately with
a gaseous mixture of nitrogen and carbon dioxide. Finally, after rigging-down the coiled tubing, a perforating assembly nearly sixty feet long is ready to be lowered into the casing and gyroscopically oriented. Sixty separate charges will be fired to perforate thirty feet of casing into the hydrate-bearing Sagavanirktok "C" sandstone, creating a pathway for injection fluids, traveling from the Gas Mixing Skid at the surface, down the wellbore, and into the sandstone reservoir targeted for this field trial. Specialized oriented perforating equipment is being employed to ensure perforations do not sever electronic and fiber-optic cables. Cables were clamped to the outside of the casing during 2011 operations and purposely cemented in-place. These cables are connected to a pressure gauge below the perforated interval in the well and distributed temperature sensors that extend outside the casing to a depth of nearly 2600 feet. After spooling the perforating gun back to the surface, additional liquid nitrogen and carbon dioxide will be heated, vaporized, carefully mixed, and pumped downhole, accompanied by small amounts of tracer gas to help quantify the exchange of carbon dioxide with methane.
Status Report - Feb 06, 2012
All essential equipment has arrived on the Ignik Sikumi #1 ice pad, including the Gas Measurement Skid, Line Heater/Pump system and Low Gas-rate Measurement Skid, which includes a separator and meters for accurate produced gas-rate determination. A gas chromatograph has been installed in the Gas Measurement Skid to ensure accurate mixing of injection gases and also to measure composition of gas produced during flow back. Liquid nitrogen and carbon dioxide injectants, glycol for wellbore heating, diesel fuel for power generation, and fresh/waste water are all stored on-site. Interconnections are being established, including hoses for low-pressure fluids, steel hard lines for high-pressure fluids, electrical power supplies for all equipment, and communication connections that include electronic, fiber-optic, and satellite . Real-time data transmission during injection and flow back/drawdown testing will be facilitated by satellite and Internet. Ignik Sikumi #1 camp, constructed on-site from eleven pre-fabricated modules, provides accommodations for 23 essential personnel as well as office space and communications/computer support.
Status Report - Jan 30, 2012
Site preparation for 2012 well testing at Ignik Sikumi began in December with the re-building of an icepad around the wellhead, which was completed December 20. Over the subsequent weeks, the facilities and equipment for conducting the work arrived at the site, including crew accommodations, power supply, and well-service equipment. Installation and interconnection of testing equipment to the wellhead is underway.
At the heart of the exchange experiment is a state-of-the-art Gas Mixing Skid (GMS), housed in an Arctic-grade shipping container. Specialized pumps, valves, and meters are required because standard oilfield equipment cannot move, mix, or measure injection gases at the pressures, temperatures, and rates required by the test design. The GMS was designed by ConocoPhillips, with input from key contractors, and manufactured in Texas. The skid was tested and commissioned near Houston, before being loaded onto trucks and driven to Prudhoe Bay on the Alaska North Slope. Other trucks carried carbon dioxide and nitrogen storage tanks for the test, as well as wellbore heating, gas measurement, and other peripheral equipment. The attached photo, made during commissioning, shows the GMS interior.
Status Report - Jan 1, 2012
The project has completed the majority of preparations for production related field trials. Specialized storage, metering and measurement equipment, necessary to carry out planned production testing operations, is on site and being prepared for use. The project officially entered its final production testing phase on December 16, 2011. Plans for the production testing phase of the project are to return to and re-enter the Ignik Sikumi #1 well, at its location adjacent to the L-Pad road within the PBU, from an ice pad, starting in late January 2012. The production testing program will consist of site and well preparations followed by well perforation and the injection of a combination of N2 and CO2 into the methane hydrate reservoir. This injection phase will be followed by an extended period of depressurization and flowback of gas to the surface. Once the exchange test objectives are met, the intent is to use the wellbore for continued production testing, including depressurization, through the remaining time within the test window.
Collection of a full suite of data from wellbore instrumentation and the analysis of well flowback will be carried out throughout production testing operations. Following production testing, the current plan is to plug and abandon the Ignik Sikumi #1 well and restore the site. Field operations will be followed by review of the data collected and the initiation of extensive analysis of that data to determine the implications of test results.
Status Report - December 2011
The project has completed the majority of preparations for production related field trials. Final testing of specialized storage, metering and measurement equipment, necessary to carry out planned production testing operations, along with training of personnel on equipment usage, is ongoing with completion planned by the end of December 2011. The project officially entered its final production testing phase on December 16, 2011. Plans for the production testing phase of the project are to return to and re-enter the Ignik Sikumi #1 well, at its location adjacent to the L-Pad road within the PBU, from an ice pad, starting in January 2012. The production testing program will consist of site and well preparations followed by well perforation, and an initial nitrogen injection. Subsequently, injection of a combination of N2 and CO2 into the methane hydrate reservoir will be carried out over about a two week period. This injection phase will be followed by an extended period of stepwise depressurization and flowback (above hydrate stability pressures) to assess the CH4 / CO2 exchange. Once the exchange test objectives are met, the intent is to use the wellbore for continued production testing, including depressurization, through the remaining time within the test window.
Collection of a full suite of data from wellbore instrumentation and the analysis of well flowback will be carried out throughout production testing operations. Following production testing, the current plan is to plug and abandon the Ignik Sikumi #1 well and restore the site. Field operations will be followed by review of the data collected and the initiation of extensive analysis of that data to determine the implications of test results.
