Steloy Castings has been actively involved in the manufacture of castings and components used in coal gasification technology, a process in which coal is turned into gas for the production of synthetic fuels used to manufacture petrochemical products.
As the process takes place at elevated temperatures, the manufacture of gasification units requires a variety of alloys from HF to high-tensile steel. Steloy Castings produces every cast component used in the manufacture of the hearth part of gasifier units, the heat resistant stainless steel main grate components, which are located at the bottom of the gasifier and consists of multiple inner and outer components.
The synfuel process involves the heating of coal in the gasifier by means of partial oxidation with steam and oxygen, after which it collects what Sasol terms as raw synthesis gas (syngas). The rotating grate is turned by mechanical gears to scrape the ash and typical contaminants that are produced, and dumps it in an ash lock.
While the synfuel process was previously exclusively used in South Africa, increases in the oil price have made the process much more financially viable and units are currently being manufactured locally for export.