Nature has been storing CO2 underground for millions of years. It’s often found with oil and gas. And for decades, Shell and other companies have injected CO2 into reservoirs to boost oil recovery. Some man-made CO2 is captured and used – for example, to put the fizz into soft drinks or to help tomatoes grow. There are three ways to separate CO2 from the other gases.
1) Using chemicals to absorb CO2 from chimney stack emissions.
2) Gasifying coal or biomass to produce “synthesis gas” …
… from which chemicals or special filters extract CO2.
Burning Fossil Fuels
3) Burning fossil fuels with pure oxygen to produce a highly concentrated stream of CO2…
…which is then separated from impurities.
Once the CO2 has been separated, it is then compressed and sent by pipeline or tanker to a long-term storage site.
Potential CO2 storage sites are carefully selected and monitored at every step. CO2 can be injected into depleted oil and gas reservoirs or saline formations…
…generally at depths of over a kilometer and where an impenetrable “cap” rock seals it in.
Over time CO2 will dissolve, and some CO2 will form minerals.