Seasonal and influent characteristic effects on hydrogen sulfide generation at a water reclamation plant

Correlations between sulfide generation and seasonal influent wastewater characteristics were identified based on a long-term monitoring program in summer and winter at a water reclamation plant. During summer, the emission rates of hydrogen sulfide (H₂S) from the liquid treatment processes increased substantially compared to those during winter due to the increased wastewater temperature. The open tanks/clarifiers were the least significant H₂S emission contributors throughout the year. For solids-handling processes, the H₂S emission rates did not change during the year due to similar sludge characteristics in the different seasons. The fate of sulfide in liquid treatment processes was investigated as an alternative to estimation of H₂S emissions. H₂S emission from the wet well and screens was proven to be robustly associated with the wastewater temperature, flow rate, 5-day biochemical oxygen demand and total Kjeldahl nitrogen levels. However, the correlation between influent parameters and H₂S emission from aerated grit chambers was not statistically significant.