Roosa Suviranta from Borealis recently completed her Master’s thesis for the SPIRIT programme. In her study she evaluated the techno-economic aspect of carbon capture integration to steam cracker furnaces, which links to the SPIRIT theme of reducing CO2 emissions.
A fresh M.Sc. (Chem.) graduate from the University of Lappeenranta (LUT), Roosa Suviranta now works at Borealis an Engineer at the company’s LDPE Plant. She first joined Borealis as an engineer trainee at Borstar pilot plant in summer 2022. Later that year, she took upon an opportunity to conduct her graduate thesis linked to the SPIRIT programme research theme focusing on CO2 reduction. As it turned out, her research topic, the techno-economics of carbon capture integration to steam cracker furnaces, confirmed her aspirations to find a job in the chemical industry.
Roosa reminds that in olefin production, most of carbon dioxide emissions are related to steam cracking furnaces. Reducing these emissions is a major step towards targeting carbon neutrality goals. Various alternatives are currently being studied to reduce the emissions of the cracking process, of which carbon capture is seen as one of the potential solutions.
Roosa continues by explaining that Aspen Plus™ flowsheet simulations and economic evaluation were used in conducting the techno-economic feasibility study evaluating the carbon capture integration to steam cracking furnaces as a solution for decarbonization of olefin production. Further, MEA-based post-combustion process was used to model the capture unit. The unit was designed to treat flue gas streams from 10 stream cracking furnaces and one hot oil furnace at Borealis’ Porvoo location. This leads to a total capacity of about 550 ktCO2 per year.
In Roosa’s study, a capital investment and operating costs were estimated for the carbon recovery unit. Steam was found to have the greatest impact on the feasibility of CO2 capture. High annual operational cost was related to low-pressure steam due to high steam consumption and price. According to the findings, the current steam price renders carbon capture economically unviable. Nevertheless, by implementing effective heat integration with olefin production and considering a rising EU ETS allowance price, there is potential to enhance the economic viability. The feasibility of full chain carbon capture and storage (CCS) is estimated assuming the transportation and storage take place as part of the Northern Lights project. At the same time, utilising the captured CO2 may also be seen as a potential alternative to storage.
Roosa is grateful for an excellent opportunity to develop her expertise in an area close to her heart. Roosa concludes: “This study has helped me to understand how important the role of companies is in developing methods for carbon capture. Borealis and the SPIRIT programme are driving this green transformation of plastics industry on a larger scale. Now that various technologies and ideas exist on how to tackle the challenge of carbon reduction in furnaces, the next steps are concrete: what are the most feasible technologies for implementation, keeping in mind that a technology which may be suitable for Finland, may not work equally well elsewhere.”
Ismo Savallampi and Mikko Rönkä from Borealis supported Roosa during her research process. Ismo concludes: “Roosa studied and managed a broad topic very well: this thesis gives us deeper understanding how this kind of concept could be practically integrated in an existing steam cracker facility, what is the most suitable technology and what are the main factors when it comes to feasibility.”