CO2 Storage Well Completed in Saskatchewan

The Saskatchewan-based Petroleum Technology Research Centre has announced the completion of a well to be used for testing the deep saline storage of carbon dioxide. At a total depth of 3,396 meters (11,141 feet), the well is the deepest in the province and is part of the Aquistore project, a partnership between the Petroleum Technology Research Centre and the SaskPower Boundary Dam Power Station. SaskPower, the electrical utility for Saskatchewan, runs three coal-fired plants in the province. 

The well was drilled near the city of Estevan in the Deadwood formation, the deepest sedimentary unit in the Williston Basin. It has produced a complete set of logs, core samples and other data that project officials say will be useful not only for CO2 storage, but also for oil companies in the area who have interests in hydrocarbon bearing formations. The Deadwood formation is made up of alternating porous rocks such as limestones and sandstones, and non-porous rocks like shales, anhydrite and salt.

A second observation well will be drilled beginning in October and is expected to be of a comparable depth. Both wells are part of a four year research and monitoring project to demonstrate that storing carbon dioxide deep underground in a brine and sandstone water formation  is a safe, workable solution to reduce greenhouse gases. Saskatchewan has previous carbon storage experience to draw upon. Cenovus Energy (formerly EnCana) has been injecting CO2 into the Weyburn Oil Field since 2000. In addition, Shell Oil piloted CO2 injection into Saskatchewan's Midale Field in the 1980's, which Apache Canada continued in 2005.

(A video that overviews the Weyburn Oil Field application, which uses CO2 from the Great Plains Synfuels Plant near Beulah, is available here.)

Sources: Aquistore, Petroleum Technology Research Centre

New Carbon Capture Bill Introduced

A bill introduced in the U.S. Senate last week would modify the existing carbon capture and storage tax incentive, which provides a credit of $10 per ton of industrial carbon dioxide used in enhanced oil recovery projects and $20 per ton for carbon dioxide placed directly in secure geological storage. The goal of the bill, which was co-authored by Senator Kent Conrad (D-ND), Senator Mike Enzi (R-WY) and Senator Jay Rockefeller (D-WV), is to make the tax credit easier to access for CO2 emitters.

Senator Conrad said this bill reflects the recommendations of the National Enhanced Oil Recovery Initiative (NEORI) for spurring new enhanced oil recovery projects. The NEORI is a working group of almost 30 energy industry members, state regulators, and environmental group members and was co-founded by the Great Plains Institute and the Center for Climate and Energy Solutions.

The Department of Energy estimates that standard oil production techniques leave as much as 80 percent of the original oil in place. Employing carbon dioxide in enhanced oil recovery could lead to a potential 67 billion barrels of economically recoverable oil — an increase of 45 billion barrels from the 22 billion barrels of current U.S. proven oil reserves, according to the National Energy Technology Lab. Read more

British Introduce New Carbon Capture Technology

A new Senate bill introduced last week aims to provide incentives for carbon capture though improved access to tax credits, but it may be a bit premature. The process has not yet been proven on a commercial scale, and some scientists think the ammonia-based materials currently used in typical carbon capture technology actually may contribute to toxic emissions during the process of trying to reduce them.

Current capture processes also require large amounts of heat to separate the carbon so that it can be transported and stored. Power plant officials complain that the capture process is "parasitic"--that is, it significantly reduces the efficiency of the plant by diverting heat to the carbon separation process.

Recent innovations, however, may improve the efficiency and reduce the cost of carbon capture. For example, the Department of Energy last month announced preliminary results of its tests with a new carbon sorbent called BrightBlack, which demonstrated efficiency rates as high as 95% and yielded carbon with purity rates between 95 and 100 percent.

In the BrightBlack process, CO2 is absorbed in a bed of proprietary sorbent pellets and desorbed in a separate reactor that regenerates the sorbent and cycles it back to the absorber at  low thermal temperatures. Through 7,000 absorption-regeneration cycles, and a total of 130 hours of operation, the sorbent showed little-to-no mechanical or chemical degradation. The DOE plans to use the data from the initial pilot project to run scaled-up trials of the process, with the eventual goal of testing it in a pulverized coal boiler.

Meanwhile, British scientists this week announced a new low-cost sorbent called NOTT-300 (from Nottingham University where some of the research occurred) made from aluminium nitrate salt, cheap organic materials and water. In additon to being non-toxic, the material enables captured CO2 to be released using virtually no heat.

The NOTT-300 technology uses two filters. When one filter becomes saturated with carbon, it is removed and the carbon is released through a pressure reduction process while the exhaust gases are diverted to the second filter. The regenerated filter is then reconnected to be used when the second filter becomes saturated, a process the Nottingham scientists say can occur repeatedly and at normal temperatures.

The capture rate during the trial was nearly 100%  The researchers say the rate could be lower in an actual power plant application but should still approach 90%. They also think NOTT-300 could be used in gas separation processes since other gases such as hydrogen, methane, oxygen and nitrogen cannot interact with the material in the same way and therefore cannot be adsorbed.

It is important to point out that these new technologies, while showing great promise, are still only laboratory experiments. It's unknown whether they will work in commercial power plant applications, which are likely many months from being tested.

Sources...

• The U.S. Department of Energy, "Novel Sorbent Achieves 90 Percent Carbon Capture in DOE-Sponsored Test", August 21, 2012
• Financial Post, "Boost for carbon capture from new non-toxic absorber", September 24, 2012
•TCE Today, "New NOTT-300 MOF offers CCS Potential", September 25, 2012