Friday, May 8, 2009
Space Requirements for the CO2 Injection Well
The quotes for this posting came from the article located here.
If you've been following this blog, as you read this article you may feel even more confused......articles written by those doing the injecting claim the injected material stays within 1/4 mile of the plant. This article talks about it migrating into a MUCH wider area. Who do I believe? For myself, I tend to follow the money ............ and usually put more credibility in those who have the least to gain from a monetary standpoint. The AWWA is here to protect our drinking supply, not make money on from sequestering COS. I have to believe they want fresh drinking water as much as we do. Your mileage may vary.
"The American Water Works Association (AWWA) and the American Public Power Association
(APPA) commissioned this article to consider the drinking water and groundwater issues associated with CO2 sequestration and to identify the regulatory and technical hurdles that might minimize opportunities for Carbon Capture and Sequestration."
"DOE has estimated that injecting 0.9 million metric tons of CO2 will require a land area of over 2,750 acres. This carbon mass is only 40 percent of one year’s generation from a 300 MW coal power plant with a 90 percent efficient CCS. Using DOE’s estimate, to hold 30 years of CO2 captured from a 300 MW boiler, the surface area requirement is over 200,000 acres, or 312.5 square miles.59 This land choice must also consider load, transmission lines, coal or rail access, surface water (used to produce electricity) and conventional air pollution issues such
as SO2 and NOX. The injection well, observational well and Area of Review (AoR) space issues will dictate where the future power plants can be built."
"The U.S. DOE’s estimate may significantly underestimate the land area needed. As a gas,carbon dioxide is different then diluted wastewaters currently injected in Class I wells. It is more buoyant than the underwater fluids and will rise to the top of the injection layer. If the injection layer has dips and rises, CO2 will flow to fill in each rise first. In other words, unlike current injected fluids, it will migrate via diffusion on its own away from the injection well."
"ike natural gas, it will concentrate in traps miles away from the injection zone. In other words, applicants could have areas of review much greater than 2.5 miles currently thought protective for liquid injection. A study in the saline formations of Texas where there are many Class I wells suggests that a formation large enough to store 30 years of CO2 from a single power plant could have traps over a 13 mile by 13 mile area.60"
"A further complication is the difference in property law traditions across the United States. In several Homestead laws, Congress gave away land to settlers who stayed upon and improved the land. However, the federal government retained the subsurface rights to the land, creating “split-estate” properties where the surface owner does not have title to the subsurface. Over 20 million acres of land in western U.S. states have split estates between private entities and the federal government.61 In other states, the mineral rights have been sold to private parties creating split estates between parties. In the eastern U.S., property titles typically include surface and subsurface rights."