Ethanethiol gas removal in an anoxic bio-scrubber

Abstract

The performance of ethanethiol removal in an anoxic lab-scale bio-scrubber was investigated under different operating parameters and conditions for 300 days. The removal efficiency (RE) of ethanethiol was examined as a function of inlet concentration, empty bed residence time (EBRT) and spray density of irrigation. The results showed the best operation conditions and operation characteristics of the bio-scrubber for this study were at an inlet concentration of 150 mg/m3, a spray density of 0.23 m3/m2 h and an EBRT of 90 s. An average RE of 91% and elimination capacity (EC) of 24.74 g/m3 h was found for all inlet ethanethiol concentrations. Variations in spray density higher than 0.23 m3/m2 h had no effect on ethanethiol RE at different ethanethiol concentrations. The average experimental yield values were closer to the YET/NO3− theoretical value of 0.74 when the main product was elemental sulphur (So). This indicates that So and other forms of sulphur were formed rather than sulphate (SO42−) as the end product. Furthermore, growth kinetics for bio-degradation were evaluated in batch culture experiments using the Monod model, and bio-kinetic parameters of μmax, Ks, Yxs and qmax were obtained as 0.14 1/h, 1.17 mg/L, 0.52 gx/gs and 0.26 gs/gx h, respectively.