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The refractory lining of the converter plays a role in the conversion — clay linings may be used when little phosphorus is present in the raw material. Bessemer himself used ganister sandstone–in the acid Bessemer process. Given high phosphorus content, dolomite or magnesite linings are used in the basic Bessemer limestone process.
It would take until 1877 for a basic lining to be developed, when the converter became economical to use with phosphorus-rich iron ores. It was a further two years before Bessemer resolved the technical metallurgical problems, at which point the Galloway ironworks were once again his test site.
The process differs essentially from the Bessemer process in the refractory lining of the converter. The latter, being made of dolomite ((Ca,Mg)(CO 3) 2) fired with tar, is basic (MgO giving O 2− anions), whereas the Bessemer lining, made of packed sand, is acidic (SiO 2 accepting O 2− anions) according to the Lux-Flood theory of molten oxides.
The process is known as basic because fluxes of calcium oxide or dolomite, which are chemical bases, are added to promote the removal of impurities and protect the lining of the converter. [2] The process was invented in 1948 by Swiss engineer Robert Durrer and commercialized in 1952–1953 by the Austrian steelmaking company VOEST and ÖAMG.
An important industrial use of ganister was as the mouldable monolithic refractory lining or brick lining for the acid Bessemer converter, a steel-making process developed in 1856 in Sheffield, England. The process could not initially be used successfully by steelworks other than Bessemer's though, owing to its need for a low phosphorus iron ore.
Open-hearth steelmaking had superseded the Bessemer process in UK by 1900, but elsewhere in Europe, especially in Germany, the Bessemer and Thomas processes were used until the late 1960s when they were superseded by basic oxygen steelmaking. The last open-hearth furnace in former East Germany was stopped in 1993. In the US, steel production ...
After the carbon content in the melt had dropped to the desired level, the air draft was cut off: a typical Bessemer converter could convert a 25-ton batch of pig iron to steel in half an hour. In the 1860s development of regenerative furnaces and higher temperature refractory lining allowed to melt steel in an open hearth. That was slow and ...
Contiguous with the investment in the furnaces was an investment in the Bessemer conversion process itself, although this investment became uncommon beyond the mid-1870s. Several Lancashire businesses developed an interest in a short space of time, including the Barrow Hematite Steel Co. which started in 1864 and operated both furnaces and ...