Design of Innovative Blast Furnace for Minimizing CO2 Emission Based on Optimization of Solid Fuel Injection and Top Gas Recycling

Abstract

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.

Three-dimensional Modelling of Coal Combustion in Blast Furnace

“…To date, a few 3D studies have been reported in the literature. [13][14][15][16][17] Murai et al 13) and Goto et al 14) reported a 3D simulation for blowpipe and on this basis some lance arrangements were examined for co-injections of coal/plastic and coal/gas. Du et al 15) reported a model for blowpipe and tuyere.…”

Numerical Study of the Gas Distribution in an Oxygen Blast Furnace. Part 1: Model Building and Basic Characteristics

“…However, the recycling gas is unevenly distributed above the shaft tuyere. The distributions of CO and CO 2 can be used to demonstrate this problem. 2.…”

“…Furthermore, the energy-saving potential of traditional blast furnace technologies has reached a limit. Fortunately, oxygen blast furnace ironmaking 1,2 can reduce more than 70% of the coke consumption, 11.1% of the energy consumption, and 59.6% of the CO 2 emissions. This process can significantly improve the energy conservation and reduce environmental pollution by transforming a traditional blast furnace.…”

Prediction of Pre-reduction Shaft Furnace with Top Gas Recycling Technology Aiming to Cut Down CO2 Emission

“…17,18) The prediction by both numerical simulation and trial BF operation indicated that the shaft injection of hot reducing gas, in which CO 2 was stripped from the recycled gas, led to an increase in production and simultaneously a decrease in fuel rate. [19][20][21][22][23] As a whole, top gas recycling technology combining shaft injection was proved to make positive contribution to cutting down CO 2 emission from BF. On the other hand, although the utilizations of COREX © 2011 ISIJ tric power generation, chemical products and BF shaft injection, [24][25][26][27][28][29][30] as a typical nitrogen-free process, it is much more applicable to capture and remove CO2 and H2O in the top gas and to recycle it for re-injection.…”