Hydrogen Sulfide Removal Comparison - Ozone versus Chlorine

摘要

The Hillsborough County Lithia Water Treatment Plant (WTP) treats groundwater supplied by two wellfields owned and operated by Tampa Bay Water - the Brandon Urban Dispersed Wellfield and the South Central Hillsborough Regional Wellfield (SCHRWF). The water is treated at the Lithia WTP for hydrogen sulfide removal utilizing cascade aeration, biological oxidation, and chloramination. The water from the SCHRWF typically exhibits hydrogen sulfide concentrations greater than 2 milligrams per liter. The current treatment process is considered to be unreliable from the standpoint of producing a consistent high quality potable supply that is free of hydrogen sulfide and heterotrophic bacteria and low in turbidity. A 90 day pilot test was conducted to document removal of hydrogen sulfide and turbidity and more completely characterize the fouling potential associated with the treatment of the SCHRWF water. The treatment processes pilot tested included oxidation with ozonation, oxidation with ozonation and media filtration, oxidation with chlorine and media filtration, and oxidation with chlorine and membrane filtration. Two different microfiltration (MF) systems were pilot tested to compare their results. The results showed that ozonation was very effective for hydrogen sulfide oxidation and no filtration downstream from ozonation was necessary for turbidity removal. The chlorination with membrane filtration was effective at hydrogen sulfide and turbidity removal but prone to fouling of the membranes.