The image above is a stark and I think artistic view of a trade which was once central to Newcastle and the area. Although now gone from the area, BHP once employed vast numbers of Newcastle residents, and supplied still more who worked in the mines supplying raw product, with jobs.
In the early 1900s Australia was demanding more and more steel and in 1911 BHP (Broken Hill Propriety LTD) decided to step in and begin to manufacture the precious resource. They decided Newcastle would be the perfect place to build their steelworks as there was a harbour which could be used for transport, a ready workforce, and they already owned land in the area. The steelworks opened in 1915.
In order smelt iron and make steel, another product was needed though – coke. To smelt iron the iron ore has to be reduced and to do this, you need carbon. Burning carbon creates carbon monoxide which reacts with the iron ore. Combine this with high heat and the iron melts and can be drained off. Coking coal is a fuel with very few impurities and an extremely high carbon content which is made from coal and widely used in the steel industry.
BHP in Newcastle made its own coke on site. To do this, they needed coke ovens which could heat the coking coal to very high temperatures, driving off impurities and leaving behind coke. This could then be either stored or transferred directly to the blast furnaces.