Feasibility of fluidized-bed bioreactor for remediating waste gas containing H2S or NH3

Pseudomonas putida for H2S and Arthrobacter oxydans for NH3 were immobilized with Ca-alginate and packed inside glass columns to form fluidized-bed bioreactors. The feasibility of the lab-scale bioreactor for the treatment of H2S or NH3 was examined. Phosphate salt, being added to the nutrient solution as buffer solution, may chelate with Ca2+ in the Ca-alginate beads, resulting in the disintegration of gel structure. When the buffer capacity of the phosphate solution was over the critical point of 33.5 mM/pH, all calcium ions in the bead were released and beads were broken. Increasing liquid flowrate and inlet gas concentration favored to H2S and NH3 removal. Carbon source addition was essential and facilitated malodorous removal for this system. Removal capacity increased with inlet concentration. However, increasing pattern was dependent of H2S or NH3. The result clearly indicated that bioreactor was suitable to be applied for the industry of livestock farm for removing wastegas containing H2S or NH3.