Iron and steel technology

In the development of this fledgling industry, BHP had the advantage of excellent metallurgists and chemical analysts transferred from Broken Hill operations. These skills were crucial in the rapid development of sound operating practices, and in particular, that for open hearth steelmaking (Leslie Bradford, a metallurgist involved in pioneering flotation became superintendent). Engineering and management skills were also important; only two years elapsed from the placement of equipment orders in USA and UK to plant commissioning, on what had been a tidal swamp.

Australian raw materials differed greatly from those used in USA and UK. The iron ore from Whyalla was of very high grade (massive haematite), while the coals in the Newcastle area were of low rank (i.e. made rather weak coke) and of high ash. With the subsequent development of integrated works at Port Kembla (Australian Iron and Steel (AIS),* 1928), Whyalla (BHP, 1941), and ofironmaking at Kwinana (AIS, 1968), a wide variety of cokes and ferrous feeds were used, each works having quite a different practice; each practice was different from any used overseas. The ability to develop sound ironmaking practices on these feeds has been a considerable challenge for Australian technologists and has been successfully met.

* BHP acquired AIS in 1935.

Ironmaking

In the early years, prior to 1950, iron-making operations at both Newcastle and Port Kembla were limited by poor coke quality (high ash, low strength at Newcastle), and iron ore which, while of high iron grade, was poorly sized and led to high alumina viscous slags, causing problems with furnace drainage. These problems were overcome in the subsequent decades, with the following notable achievements:

the commissioning of the No. 2 sinter plant at Newcastle Works in 1961: the largest in the world at the time. Research and development carried out by BHP on sintering of Australian ores was an important factor in the development. This plant continues to be the sole source of sinter to Newcastle, supporting high performance ironmaking.

the development of fluxed sinter at both centres in the late 1950s, and early 1960s, at the same time that the technology was implemented in Japan; this led to improved sinter plant performance (large drop in recycled fines) and a large improvement in blast furnace productivity and coke rate (fluxed sinter eliminated direct limestone charging)

in the late 1950s, No. 3 blast furnace at Port Kembla became one of the world leaders in iron making productivity

No. 4 blast furnace at Port Kembla established a world monthly production record in late 1962. This achievement was due to a variety of factors, including in particular the use of fluxed screened sinter (90 per cent of ferrous burden). The performance of this furnace can only be described as remarkable, since the record was achieved without high blast temperatures, oxygen enrichment or fuel injection. In addition the slag contained 24 per cent Al₂O₃: from the perspective of the 1980s, such slags led to low productivity and unstable operation. Many overseas delegations (including the Japanese) came to Port Kembla to study how this performance had been achieved.

the development of satisfactory coke at Newcastle from low rank coals. Improvements have been achieved by the introduction of Illawarra coals of higher rank and higher content of inerts; in 1955 when this practice was first undertaken British Commonwealth production records were far exceeded for furnaces of this size: the furnaces achieved a world quality performance. In addition, performance with less than world quality coke has been assisted by the use of very high levels of injectants; Newcastle was at the forefront of injection technology in the mid 1960s, and now operates with the highest levels of oxygen and natural gas in the Western World. There are no blast furnaces anywhere in the world operating on coke similar to that at Newcastle, achieving comparable results

Australian Academy of Technological Sciences and Engineering