(3gk) Feasibility of Low Rank Coal (LRC) Gasification Process in Iron-Making Plant

To cope with economic challenges in terms of sustainable operation, many techniques for saving the manufacturing cost of pig iron using low-cost fuel have been studied. Pulverized coal injection (PCI) is one of the widely applied technique to improve the economics of blast furnaces. Unfortunately, there are several technical issues with PCI in the real industry field. First, PC does not undergo a sintering process, rather it is only physically crushed and resized. When a large amount of PC is blown to, there is a problem in permeability, and as a result, the combustibility is worsen. Second, an ash content of the PC causes an indirect problem. Due to high melting point of ash, the mobility of the slag decreases which causes blockage at the bottom in blast furnace. To avoid these problems, the most of the coals currently being applied to PCI is a relatively high rank coal (HRC).

Low rank coal (LRC) is advantageous in that its price is not expensive and its reserves are abundant, and also there have been many attempts to utilize it in recent years. Notable thing is that it also can be injected into the blast furnaces as a heat source and reducing agent. In this respect, LRC gasification could be a good alternative to solve the above technical issues.

The objective of the study is to evaluate the technical feasibility of the tuyere injection of LRC gasification products into the blast furnace.

By designing LRC gasification and cleaning process, we can make purified syngas (1% < for H₂O, 3% < for CO₂) which can be injected into the blast furnace confirming the technological feasibility of LRC gasification process.