This study compared H₂S removal efficiency of two types of deodorants (NOx deodorant ACE and Fe³⁺ deodorant S) at high temperature versus low temperature (summer/winter). For both temperature conditions, NOx deodorant ACE removed H₂S by 99% or more within 2 hours at the least dose of 2.5% (w/w), and this lasted for about 8 hours maximum. Fe³⁺ deodorant S removed H₂S by 99% or more at the dose of 5.0% (w/w), and this lasted for about 6 hours maximum. For the sludge where H₂S exists at high concentration, NOx deodorant ACE was the most appropriate. For Fe³⁺ deodorant S, additional alkaline chemicals are expected to be necessary.