Coal Characterisation for PCI

A technical review has been undertaken on coal characterisation of Pulverised Coal Injection (PCI) with the aim to prioritise research areas where Australian research organisations can make a significant contribution to the understanding of the impact of coal characteristics on PCI.

This technical review expands on the ACARP project completed by Bennett and Holcombe (1994) and recent studies that have been undertaken by CoalTech for Australian coal companies and the Queensland Government. Some of this recent work has been reported by Bennett (1997a, 1997b).

As PCI technology matures, operators are now no longer focussing their research on problems associated with implementing PCI systems, eg lance design and blockages in transport lines. The current research into PCI is examining:

• the impact of coal quality on blast furnace performance,
• how high rates of coal injection influences the stability and productivity of blast furnaces,
• improvements in coke size and quality required for high PCI rates.

Recently, there have been a large number of papers published in both the open literature and in company technical reports covering the experiences of steel makers in Europe, China and Japan. In addition, the level of understanding of the combustion characteristics of coal under the severe conditions of the raceway and gasification has progressed.

This report has summarised these recent findings showing the differences in research directions of the major producers and highlighting the impact PCI coal quality on the operation of the blast furnace. Where possible the blast furnace performance parameters have been directly related to coal properties. As a result of this review possible research areas that are required to meet the needs of the Australian Coal Industry are identified.