HOW CAN CARBON CAPTURE BE APPLIED AS PART OF A CIRCULAR ECONOMY?

New carbon capture and utilization technologies are being developed around the world to mitigate climate change and maximize material efficiency. These technologies enable the transition from a linear fossil-based carbon economy to a circular economy that utilizes emissions.

Capturing carbon emissions has been identified as playing an important role in mitigating climate change. Carbon capture is a method in which a large part of the CO2 emissions generated by industry can be recovered and either stored or utilized as a raw material, for example in the production of methane.

MAB Powertec has started a project with Lounavoima Oy with the purpose of finding a carbon capture technology suitable for Lounavoima’s waste-to-energy power plant. The aim is to separate carbon dioxide from the power plant’s flue gases, which is to be further processed into methane. Methane can be used, for example, as a transport fuel. Anna Pääkkönen from MAB Powertec works as a senior specialist in the project: “There are many steps and criteria involved in the selection and optimization of the recovery method, as the selection is influenced by various factors. Depending on the application of CO2, there are certain requirements for the purity of the CO2 and the overall solution must also be economical.

 

How does carbon capture work?

In carbon capture, CO2 from various carbon sources, such as power plants and industrial processes, is purified and captured instead of being released into the atmosphere with flue gases. Several different techniques exist and are being developed for the separation of carbon dioxide from gas mixtures. After its separation, carbon dioxide can either be stored (Carbon Capture and Storage) or further processed (Carbon Capture and Utilization).

Several methods are available for capturing carbon dioxide from flue gas. In post-combustion, carbon dioxide is removed from the flue gas by scrubbers after the fuel is used. In pre-combustion, solid fuel is first converted to a gaseous form. Carbon dioxide is removed from the product gas and captured, and the remaining hydrogen is used as boiler fuel. The third recovery method used is called oxy-fuel combustion, which uses pure oxygen to burn the fuel. In this case, the flue gas is almost pure water vapor and carbon dioxide, which can be easily separated from each other.

There are also many potential carbon dioxide storage technologies. Carbon dioxide can be, for instance, injected into undersea rock formations, stored in biomass, or stored in solid minerals by chemical reactions. After its capture, the carbon dioxide can also be processed into other substances or materials, such as chemicals, plastics or biofuels. In the best case, the carbon dioxide produced from the use of refined biofuels, for instance, could be captured again, and reused indefinitely. So far, most storage and recovery technologies are under development, however, their importance in mitigating climate change is constantly increasing.

 

What are the environmental benefits of carbon capture?

New carbon capture and utilization technologies are being developed around the world to mitigate climate change and maximize material efficiency. These technologies enable the transition from a linear fossil-based carbon economy to a circular economy that utilizes emissions. This project is part of a larger circular economy model in which unrecyclable municipal waste is converted into cleaner local energy at the Lounavoima waste-to-energy power plant, and at the same time the carbon dioxide generated from the process is recycled for new use. In addition, the waste heat generated in the carbon capture process could also be utilized as district heating. “Carbon capture will minimize emissions from the waste incineration sector. Considering the bio-based proportion of waste fractions to be incinerated, the process acts as a carbon sink. Globally, the carbon-neutral nature of waste incineration is of great importance to the climate. Utilization of the waste heat generated in the carbon capture process improves the economy of the overall process. This is a significant project for the whole industry,” Anna emphasizes.

 

As part of our engineering and project services, MAB Powertec Oy offers versatile studies and expertise for energy production concept construction, from technology studies to technical and economic evaluation. We help our clients accomplish even the most demanding projects on the principles of sustainable development and strive for responsible actions throughout the supply chain. Contact our experts for more information.

Anna Pääkkönen
Senior Specialist, PhD. Energy Engineering
anna.paakkonen(at)mabpowertec.fi
+358 40 718 7114