Costs and potential of carbon capture and storage at an integrated steel mill: Technology screening and development pathway

A full chain assessment of carbon capture and storage (CCS) applications for iron and steel industry was done in order to screen technology options and build a development pathway to low carbon steelmaking to prepare for future carbon constrained world. A techno-economic assessment of application of CCS in iron and steel industry and ship transportation of CO2 to permanent storage with different technologies was made to create knowledge basis for largest steel mill in Northern Europe. The assessment further leads to estimation of potential and wider implications of applying CCS to iron and steel industry. Different technological possibilities and the feasibility of applying carbon capture at an integrated steel mill based on blast furnace process, in order to reduce carbon dioxide emissions of a steel mill site were studied. Technologies considered for capturing of CO2 are post-combustion carbon capture (PCC), pre-combustion capture in connection to blast furnace fired gas turbine and oxygen blast furnace route (OBF). 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 steel production base case with varying costs of CO2 emission allowances. Furthermore the effect of reducing the carbon intensity of steel production on the final steel production cost is evaluated. Carbon capture processes and process integration options were modeled using Aspen Plus process modeling software and the results were used to estimate CO2 emission reduction possibilities and carbon abatement costs at the integrated steel mill from an investor's point of view. Costs, different heat integration options and heat utilization scenarios were investigated and optimized with a custom-built CC-SkynetT economics toolkit. With a whole chain approach, including CO2 capture, processing, transport and storage, results show significant reduction potential at an integrated steel mill with all carbon capture technologies. Staged construction and implementation of CCS in order to minimize financial investment risk was considered and several pathways for implementation were analyzed. With the development pathway approach, shared risk due to staged investments enable lower threshold for going for CCS investments. Different technologies are differently suited for the approach and in some cases staged construction can bring financial and emission reduction benefits already before implementing full chain of CCS