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Expanding CCS at an LNG facility in Australia
How we helped Chevron capture CO2 from its Gorgon facility and store it beneath Barrow Island
While emerging sources of energy such as solar, wind and hydrogen are critical to a low-carbon future, we also need to reduce the carbon intensity of new and existing hydrocarbon facilities that support our energy needs today.
Finding a solution for CO2 emissions
The Gorgon natural gas field contains 14 percent naturally occurring CO2. This CO2 must be separated from the natural gas stream prior to liquification to prevent it from freezing into a solid.
The industry standard approach is to vent this CO2 into the atmosphere. But as a cleaner alternative to this process, Chevron began the largest greenhouse gas abatement project ever undertaken in our industry to capture and store CO2 in rock formations beneath Barrow Island in Western Australia, where its Gorgon LNG facility is based.
Safely handling millions of tonnes of CO2 every year
We were involved in the engineering, procurement, construction, commissioning and start-up activities of the CO2 injection facilities. These facilities process, transport and inject unwanted CO2 into rock formations more than 2 km underground.
Our experts implemented several modifications to ensure the injection facilities met their required parameters for water content and injection temperature. To reduce water content and therefore prevent corrosion in the facilities, we used an enthalpy-based internal refrigeration cycle to increase the dewpoint of the CO2 gas to acceptable levels.
Other system improvements included the installation of a hot-gas bypass line, cold-recycle line, methanol and glycol (MEG) injection package and wastewater treatment package. In total, we installed 1,500 new valves, 9 km of process piping and 450 tonnes of supporting steelwork.
Cutting emissions by 40 percent
We applied our understanding of the intricate behavior of CO2 at a large scale, along with our experience executing complex projects, to enable the safe start-up of the CO2 injection facilities in mid-2020.
As a result, carbon emissions from the Gorgon LNG facility will be reduced by approximately 40 percent. This equates to four million tonnes of reservoir CO2 injected into the Dupuy Formation beneath Barrow Island each year, which will save approximately 100 million tonnes of CO2 from being emitted over the life of the Gorgon project.
