What is Carbon Capture Technology? Why it is important to Energy Industry?
Despite what skeptics say, climate change is real. And according to numerous reports, its catastrophic consequences are almost here. Without swift action, global temperatures will rise by 1.5 °C by 2030 and 2 °C by 2050—and will continue to surge rapidly says The Intergovernmental Panel on Climate Change (IPCC). This increase will lead to disastrous effects, such as record-breaking sea-level rise, flooding, wildfires, extreme weather events, famine, and wildlife habitat destruction. What’s most frightening is that research suggest that humans are on a path to generate so much carbon dioxide and other greenhouse gases that it might be nearly impossible to cut emissions enough to avoid the worst. Fortunately, carbon capture and storage technologies can reduce global carbon dioxide emissions by almost a fifth and reduce the cost of tackling the climate crisis by 70%, The International Energy Agency says.
What is Carbon Capture Technology?
Carbon capture technologies refers to the chain of different technologies that use physical and chemical techniques to prevent the release of carbon dioxide (CO2) produced by major factories and power plants through conventional power generation and industrial production processes. Basically, CC technologies functions over three major steps: CO2 capture, CO2 transportation and CO2 storage.
CO2 capture and separation are done at the source – the facility emitting CO2) using several technologies. They can be categorized into three: post-combustion carbon capture (the primary method used in existing power plants), pre-combustion carbon capture (largely used in industrial processes), and oxyfuel combustion systems. Post-combustion carbon capture involves the separation of CO₂ from the exhaust of a combustion process. At the same time, pre-combustion entails gasifying fuel and separating the CO₂. This technology is commercially available for industrial facilities; but still in early stages for power plants. Although it may the most cost-effective CO2 separation technique, it can only be built into new facilities—to retrofit an existing facility for pre-combustion capture would be prohibitively costly. For oxyfuel combustion, fuel is burned in an almost pure-oxygen environment, instead of in regular air, which results in a more concentrated stream of CO₂ emission, which is easier to capture.
After the highly concentrated gas is captured, it is compressed into liquid and transported to storage points or reservoirs commonly via pipelines or ship and occasionally by trains or other vehicles. Some appropriate geological storage locations that will ensure that the CO2 doesn’t contribute to climate change include depleted oil and gas wells, deep saline formations and unminable coal seams or it can be directly injected deep into the ocean.
Advantages of Carbon Capture Technologies
The primary reason for utilizing carbon capture technologies is CO2 emission reductions from industry and power generation. According to the Global CCS Institute, annually 40 million metric tons of CO₂ from plants currently in operation or construction are captured and stored. The deployment of CC would also allow these facilities to continue using fossil fuel with a significant decrease in emissions.
During CO2-based steam cycles, where CO2 is pressurized into a supercritical fluid, heat can be transferred more readily, and less energy will be needed to compress steam, helping power generation turbines run more efficiently. Also, geologically stored CO2 could be used to extract geothermal heat from the same locations in which it’s injected, generating renewable geothermal energy.
In some cases, separated CO₂ can be utilized in the production of manufactured goods and in industrial and other processes, rather than being stored underground. Another primary use of CO₂ is for enhanced oil recovery (EOR), a method of oil extraction that uses CO₂ and water to drive oil up the well, improving oil recovery and sequestering the CO₂ underground. Besides, selling CO₂ for EOR and other uses can provide revenue to CC technologies facilities, incentivizing further implementation of Carbon Capture technologies.
Limitations of Carbon Capture Technologies
Despite the remarkable potentials and favorable environmental impacts of carbon capture technology, considerable drawbacks exist, including expensive operation and transportation, the environmental threat of long term CO2 leakage and uncertain public support. Presently, the high cost of implementation is of the most significant barriers to widespread deployment of CC technologies. Although cost estimates vary widely, the greatest costs are usually associated with the equipment and energy needed for the capture and compression processes. Also, significant energy is needed to maintain high pressure of the compressed CO2 throughout pipelines, and the pipelines are expensive, thus making transportation cost-intensive. To mitigate these challenges and accelerate CC development, policies that increase demand and reduce the costs should be implemented by appropriate authorities.
Above all, a technology that can keep carbon dioxide emissions from entering the atmosphere and stoking global heating is crucial in tackling the growing climate crisis. Carbon capture technology and storage projects are particularly essential to heavy industry – fertilizer producers, steel mills and cement makers – that often find it difficult and expensive to adapt to run on cleaner energy. Also, the carbon separation process offers a more effective method of producing hydrogen – a clean-burning gas that could be used to replace fossil fuels.