AWWA JAW49839

To determine water quality effects on groundwater treatment for hydrogen sulfide, the authors compared sulfuric acid (H2SO4) and carbonic acid for pH adjustment pretreatment in a pilot-scale (40-gpm [2.5-L/s]) randomly oriented packed tower. Pretreatment with either H2SO4 or carbon dioxide (CO2) to pH 6.0 resulted in >95 percent sulfide removal for tower feedwater sulfide concentrations of 2.5 mg/L. However, utilization of H2SO4 for pH adjustment resulted in a loss of alkalinity in the finished water and an increase in sulfur (as sulfate), whereas CO2 pretreatment preserved alkalinity in the finished water and did not increase sulfur (as sulfate). Includes 23 references, tables, figures.