CCS pre-combustion and storage
In this continuing series on Carbon Capture and Storage (CCS), we discuss techniques to remove and capture CO2 prior to combustion.
In my previous blog I discussed post-combustion scrubbing as a CCS technique to remove and sequester CO2 in operations where hydrocarbon fuels are burned for power generation. In the case of heavy oil production, this might also include large scale co-generation facilities where produced heavy oil is burned to produce steam for SAGD or CSS.
There are also pre-combustion decarbonization techniques where the CO2 is extracted from the hydrocarbon fuel source and captured for storage before it is burned. This process typically involves converting the hydrocarbon fuel source to hydrogen and CO2 in a reformer; the CO2 is compressed for storage and the hydrogen is mixed with air for combustion, emitting only nitrogen and water.
A third method of carbon capture involves separating oxygen from air and then burning it with hydrocarbons to produce an exhaust with a high concentration of CO2 for storage; extracting sufficient concentrations of CO2 from flue gas emissions is a challenge and one oxygen firing may help solve.
There are four primary plant sources of large quantities of CO2 including, electric power utilities, cement plants, oil and gas refineries, and ethanol plants. Oil refineries including those that upgrade and refine heavy oil are good sources of high-quality CO2 with potential purities at 99+%, making capture more economically viable and efficient.
In terms of CO2 storage and application to heavy oil EOR, several large-scale geological storage projects are already in operation, and many more have been proposed. I found the website http://www.geos.ed.ac.uk/sccs/storage/storageSites.html to be a useful reference on the subject and it has an interactive map that shows the locations of existing and proposed CO2 storage projects. The CO2 Capture Project is also a great online reference and includes a number of oil industry related projects.
CCS as means to reduce GHG emissions and provide a mechanism for EOR, will continue to present our industry with many challenges and require new capture and storage technologies and services including site assessment, site characterization, site design and construction, monitoring, and decommissioning.
Please look for more discussion on carbon storage and the application to heavy oil in coming blogs and please continue to share your thoughts and questions in our Forum.
Kambiz.
