Simulation and multi-objective optimization of liquid hydrocarbons production by coupling Blast Furnace Gas with Coke Oven Gas of steelwork

Steelwork is one of the main CO₂ emitters due to three main off-gases of blast furnace gas, coke oven gas, and basic oxygen furnace gas. Many efforts are being made to reduce CO₂ emissions by unit optimizing or by carbon capture and storage processes. In this paper, the simulation of blast furnace gas and coke oven gas recovery is investigated using Aspen HYSYS. For this purpose, a part of the blast furnace gas gases is mixed with the coke oven gas and injected into the Fischer–Tropsch reactor to produce liquid hydrocarbons. The process has been optimized by response surface methodology using Design Expert. The optimized simulation results showed that by mixing a portion of blast furnace gas and coke oven gas, the syngas was provided without fuel consumption in the reforming unit in both the reactor and utility system, while C₅⁺ and C₂-C₄ were produced by 219Mbbl/day and 380Mbbl/day. At the same time, CO₂ emissions decreased by 51%.