STAINLESS STEEL IN MODERN SULPHURIC ACID PLANTS.

The use of stainless steel became a part of optimization investigations and tests that were started in 1981 and carried out by Monsanto Enviro-Chem of St Louis, Missouri, U. S. A. , a world leader in the design and supply of sulphuric acid plant. The use of stainless steel for converters and heat exchangers, which, in a plant such as that of the Palabora Mining Company totals approximately 300 t, is rapidly gaining acceptance. Stainless steel gives greater strength at a lower mass, and a longer life with less maintenance, and allows for improved plant layout and operation. Also, and perhaps most important, it is suitable for use at higher gas strengths and high absorption temperatures, while overall, it costs less than cast iron and treated mild steel, and allows more economically efficient operation to be achieved under operating conditions that cannot be withstood by conventional materials.