Design of Innovative Blast Furnace for Minimizing CO_2 Emission Based on Optimization of Solid Fuel Injection and Top Gas Recycling

摘要

The concept of innovative ironmaking process for aiming at energy half consumption has been proposed based on the basic experiments and mathematical calculations. For innovative ironmaking process, intensive combustion technology around raceway was examined by hot model experiments and three-dimensional mathematical simulation so as to utilize solid fuel such as plastics effectively. As results, it became clear that simultaneous injection of pulverized coal/plastics or pulverized coal/gas fuels is favorable to improve combustion efficiency remarkably. Decrease in thermal reserve zone temperature and top gas recycling besides plastics injection are found to be effective for lowering coke rate. In this process, productivity can be also improved owing to relaxation of flooding condition in the lower part of blast furnace. Productivity of 3.5 and more, that is determined by fluidization condition at top, can be expected in this innovative ironmaking process. Totally, it is evaluated that amount of carbon emission would be reduced by eighty-six percent provided sequestration of carbon dioxide is implemented. Finally, integrated ironmaking process with co-generating oxygen production process was proposed.