Overview of Techniques Applicable to Sulfuric Acid Production

3 Overview of Techniques Applicable to Sulfuric Acid Production 

This section refers to existing plants which may (or may not) be up-graded, although not reaching the specifications of new plants. 

The six process routes are the principal process routes that are available. The following data on production processes have been presented in detail in the previous paragraphs and are summarized in Table 2.2 using an O2/SO2 ratio of about 1 0.2 (possibly 0.8-3). 

The S02-containing gases, which have been carefully cleaned and dried, are oxidized to sulfur trioxide in the presence of catalysts containing alkali and vanadium oxides. The sulfur trioxide is absorbed by concentrated sulfuric acid in absorbers, preceded if necessary by oleum absorbers, hi the absorbers, the sulfur trioxide is converted to sulfuric acid by the existing water in the absorber acid. 

The absorber acid is kept at the desired concentration of approximately 99 wt% by adding water or dilute sulfuric acid. 

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