With the increased concern of global greenhouse gas emissions, scientists are researching ways to limit the amount of CO2 entering the atmosphere in an effort to mitigate the atmospheric CO2 concentration increase. Currently there is a global push to limit CO2 emissions through Carbon Capture and Storage (CCS) technologies. These large projects require strategic planning and public acceptance for them to be successful.
The Virginia Center for Coal and Energy Research is using the LI-8100A to monitor soil CO2 flux near the injection well.
Southeast Regional Carbon Sequestration Partnership's Central Appalachian Coal Seam Project Coal Bed Methane Injection well.
One of the biggest concerns with CCS is whether or not the CO2 remains within the geologic formation into which it was injected. The post-injection migration of CO2 in time scales of years, decades, and even centuries is not well understood. Despite the fact that CO2 is injected thousands of feet below the surface, the risks and potential for failure are very real. A well organized surface monitoring campaign should include a pre-injection background study to better understand the natural variation in soil CO2 flux over the surface of the injection area. By establishing baseline CO2 fluxes, the researcher can say with confidence that routine post-injection monitoring is effective and can provide quantitative data to prove a leak has not taken place. An active surface monitoring campaign can also be used to ease public perception of any potential leak concerns. Even though the risk of a leak in most cases is very low, using surface monitoring techniques is a valid way to convince the public that the CO2 has not escaped to the surface.
Surface Monitoring Instrumentation for Geologic Sequestration
LI-COR Biosciences has specialized in ambient CO2 monitoring for over 25 years. Our open and closed path CO2 analyzers are used worldwide in many different applications. In terms of CCS technology, LI-COR offers a modular LI-8100A Automated Soil CO2 Flux System that can be used to monitor surface leaks and natural background fluxes in multiple locations. The LI-8100A uses a chamber accumulation technique to determine soil CO2 flux. Another method of leak detection is to map ground level CO2 concentrations or fluxes in which the LI-8100A Analyzer Control Unit is used with a GPS receiver to collect and map real time CO2 data (see figure below). LI-COR also offers the LI-7500A Open Path CO2/H2O Analyzer that is commonly used in Eddy Covariance measurements to determine the vertical CO2 flux over a relatively large area. The Eddy Covariance method is an effective way to monitor large areas where CO2 may escape from the subsurface. Complete Eddy Covariance solutions are available from LI-COR, which include system components, software, training, and resources.
The LI-8100A System is already being used in a number of CCS projects all over the world. One example is in the Southeast Regional Carbon Sequestration (SECARB) Partnership's Central Appalachian Coal Seam Project. The Virginia Center for Coal and Energy Research (VCCER) at Virginia Tech is using the LI-8100A to acquire baseline data prior to an injection at a coalbed methane (CBM) well. Their field validation objectives are to assess and verify the sequestration capacity and performance of mature CBM reservoirs in the Central Appalachian Basin through injection-falloff and production testing, as well as the implementation of monitoring programs. These tests will demonstrate the potential geologic sequestration into Appalachian coals as a safe and permanent method to mitigate greenhouse gas emissions. Monitoring will be divided into pre-injection, injection and post-injection phases. The pre-injection monitoring phase started in the Spring of 2008 by obtaining a soil CO2 flux baseline.
- Soil CO2 Flux Measurements: Addressing Spatial Variability: Determining the Number of Readings Required
- Measuring High CO2 Flux Rates with the LI-8100A Automated Soil CO2 Flux System
- Surface Monitoring for Geologic Carbon Sequestration
- Carbon Sequestration Pilot Studies and the LI-8100
The following LI-COR Analyzers can be used to Study Carbon Sequestration
Soil CO2 Flux System
- Measures CO2 exchange from soils
- Multiplexed configuration available for larger sampling area
- Useful for survey or long-term measurements
Complete Eddy Covariance Systems
- Turnkey systems to measure CO2, H2O, and CH4 flux
- Open path and enclosed path options
- Modular systems can be expanded with additional biomet sensors
LI-7500A Open Path CO2/H2O Analyzer
- In situ open path measurements
- Designed for field use
- Low power consumption
LI-840A CO2/H2O Analyzer
- Practical for continuous monitoring applications
- Compact and lightweight
- User-cleanable optics