Effect of tube size on performance of a fixed-film tubular bioreactor for conversion of hydrogen sulfide to elemental sulfur

A fixed-film continuous-flow photobioreactor was used for the removal of hydrogen sulfide from synthetic industrial wastewater and conversion of it to elemental sulfur using sixteen 150 mm length Tygon tubes as the active part of the reactor. Three different tube sizes (internal diameters (ID) 6.4, 3.2, and 1.6 mm) were used to investigate the effect of tube size on reactor performance. The reactor with 1.6 mm tube attained a higher sulfide loading (1451 mg/L h) than previously reported in the literature. High bacterial concentration, light to volume ratio and intimate contact between attached bacteria and influent sulfide resulted in excellent performance of the 1.6 mm tube reactor.