Domestic sewage typically contains between 20 and 500 mg/l sulfate. Several
industrial wastewaters contain much higher concentrations of sulfate, sulfite, or
other sulfur compounds. Contamination of industrial wastewaters with sulfur
compounds can be due to the use of sulfur-containing materials in industrial
process applications (e.g., the food and the pulp and paper industry) or to sulfate-containing process water (e.g., sea water)