AMBIENT AIR MONITORING OF LOW LEVEL HYDROGEN SULFIDE

This paper describes the screening and evaluation of hydrogen sulfide analyzers for concentration measurements in the low part per billion ranges. Monitoring of ambient air for hydrogen sulfide below the threshold of the human nose is a technology that can be used by wastewater treatment plants for odor monitoring. Two types of technologies were chosen and compared in both laboratory and field settings. The initial screening involved eight different technologies used to measure hydrogen sulfide concentration in air. The evaluation criteria were based on detection limit, range, reliability, maintenance, application and cost. The lead acetate tape and the pulsed fluorescence technologies were chosen and compared side by side. The initial comparison in a laboratory setting indicated a good correlation between the two instruments. The preliminary evaluation of the analyzers in an area known to have ambient hydrogen sulfide was conducted. Two monitoring stations were set up at the Calumet Water Reclamation Plant. The results indicate that both instruments correlate well with each other.