The link between greenhouse gases and global climate change has prompted countries worldwide to adopt environmental standards that cap CO2 emissions and aim to dramatically reduce emissions rates (e.g., the Kyoto Treaty, the Kyoto Protocol amendments and the Bali conference).
Although the U.S. has not ratified the Kyoto Treaty, in April 2007 the U.S. Supreme Court ruled CO2 to be a pollutant and determined that the Environmental Protection Agency has the authority and obligation to regulate CO2 emissions from vehicles. EPA is expected to regulate greenhouse emissions from fossil fuel-fired power plants in the future.
State and federal government agencies, the American public and a range of industries involved in fossil fuel production and use are concerned about the degree of reduction and methods to mitigate CO2 and other greenhouse gases. Individual states have legislated caps on CO2 emissions, and various federal bills require substantial reductions in carbon emissions from power plants.
Although gaps exist in the technologies available for capture and separation of CO2 from the flue gas, the liability issues related to sequestration (storage) sites and the long-term stability of stored CO2 remain the major concern to the industry. WRI is conducting research and developing technologies to address carbon capture and storage (CCS). Examples include:
Oxy-combustion. WRI and our industrial partner are evaluating processes for the production of oxygen for use as part of oxy-combustion of fossil fuels. Oxy-combustion is a process for concentrating the CO2 in the flue gas, thereby avoiding the need to separate the CO2 from other flue gas constituents, such as N2.
Sorbent Development and Testing in WRI’s Sorbent Test Facility. Methods to economically capture CO2 from the flue gases of coal-fired power plants are currently lacking. WRI is developing multi-pollutant sorbents that selectively remove air emissions, such as mercury, arsenic, selenium and carbon dioxide, from flue gases for disposition or, in the case of CO2, compression, transport and storage.
Biological Processes Involved in Carbon Storage. The sequestration of CO2 in geological formations and abandoned oil fields and its use in enhanced oil recovery (EOR) applications is blocked by a lack of understanding of the impacts of biological processes on the stored CO2. WRI is evaluating these biological processes and their impacts.
Tracers for Monitoring Subsurface Sequestered Carbon. The largest uncertainty in the capture and storage of CO2 in subsurface geological formations or in enhanced oil recovery (EOR) is the liability issue. Central to that issue is the lack of means to monitor the stability of the stored CO2 and to raise an alert in the case of any unexpected mobility. WRI is developing tracers that can be used to monitor the movement or leakage of stored CO2.