Carbon dioxide sequestration
Carbon dioxide (CO2), a colorless, odorless gas, is a natural and critical component of the atmosphere. It is one of several greenhouse gases that are essential to maintaining life-sustaining temperatures by allowing heat from the sun to penetrate Earth’s atmosphere but not escape back into outer space. Too much CO2 in the atmosphere, however, is detrimental to the environment.
CO2 is produced through natural and human processes, but worldwide CO2 emissions from human activity—burning oil, gas, and coal, for example—have increased from an insignificant level two centuries ago to more than 33 billion tons annually. At the same time, CO2 concentrations in the atmosphere have increased dramatically. To curb these trends, scientists are studying the feasibility of capturing and permanently sequestering, or storing, CO2.
Scientists at the KGS are studying geologic sequestration and related issues. A major research project focuses on the potential to store large amounts of CO2 in saline aquifers, where the highly saline water is not usable for other purposes and would dissolve the CO2. The Arbuckle Group, a series of 480 million year old rock layers found deep underground in Kansas, is a potential target for CO2 storage.
KGS scientists also have investigated the practicality of injecting CO2 into underground coal beds to displace coalbed methane, which could then be processed and used.
In a collaborative effort between government and industry, the KGS is leading a multiyear project to determine the potential long-range success and safety of capturing and injection CO2—emitted by power plants and other industrial sources—into the ground. Researchers are testing both its use in the production of hard-to-reach oil in a nearly depleted oil field and the permanent storage of the CO2 into the deep Arbuckle aquifer. The Arbuckle formation is a porous rock group that contains extremely saline, or salty, water in the study area and is separated from shallower, fresh groundwater sources by thousands of feet of impermeable rock.
Geologic Sequestration of Carbon Dioxide in Kansas: Kansas Geological Survey Public Information Circular 27.