Feasibility of CCS at an integrated steel mill: a case study

In this study different possibilities and feasibility for applying post combustion carbon capture (PCC) at an integrated steel mill in order to reduce carbon dioxide emissions were studied. Implications of different capture amounts, different solvents for post combustion capture and process integration levels to the greenhouse gas balance and operation economics are compared to the base case steel production with varying costs of CO2 emission allowances. Case study is based on Ruukki Metals Oy's Raahe steel mill that is situated on the coast of the Gulf of Bothnia. It is the largest integrated steel mill in the Nordic countries producing hot rolled steel plates and coils. It is also the largest CO2 point source in Finland emitting approximately 4.5 Mton / year (in 2008). Carbon capture processes were modeled using Aspen Plus process modeling software and results were used to estimate CO2 emission reduction possibilities and carbon abatement costs at an integrated steel mill from investor's point of view. Different heat integration options and heat utilization scenarios were investigated. Heat available for solvent regeneration varied between these heat utilization scenarios and thus different capture amount were investigated depending on the heat available for solvent regeneration in different case studies. With a whole chain approach, including CO2 capture, processing, transport and storage, results show how much CO2 emissions can be avoided at an integrated steel mill in a whole. The study also reveals some major technical restrictions of the application. Results show also the cost structure and feasibility of the studied technology. Finally the pros and cons of the technology are compared