Cost Minimization with Optimal CO2 Mitigation Options for the Steelmaking Industry

The energy-intensive production process for the steelmaking industry has been the focus nowadays because it contributes directly to the global warming issue. There are several processes within the steelmaking industry that contribute to this issue by emitting CO2 emissions mainly from combustion of fossil fuel to supply the desired energy. There are different ways to control these emissions, and improving energy efficiency is one way to do that. Nowadays, there are several advanced techniques or technologies that can reduce CO2 emissions further. One of these options is using less carbon fuel, leading to less CO2 emissions. Another technique that can achieve higher reduction targets is CO2 capture. In this study, a mixed integer nonlinear programming model is developed to select the least cost CO2 reduction technologies for different reduction targets for a steelmaking plant. The options considered are improvement of energy efficiency, fuel switching, and application of capture technologies. The results show that improvement of energy efficiency is not a promising option at different reduction targets because it can achieve very low reduction targets. Fuel switching has to be implemented to achieve a CO2 reduction target up to 30%. The steel production cost increases up to $483/ton if the fuel switching option is applied. Carbon capture using monoethanolamine is applied if the reduction target is higher than 30% and the cost of steel produced increases to about $617/ton at a reduction target of 65%.