Removal of hydrogen sulfide and ammonia from gas mixtures by co-immobilized cells using a new configuration of two biotrickling filters.

The simultaneous removal of H(2)S and NH(3) was investigated using two biotrickling filters packed with polyurethane foam cubes. One biotrickling filter was inoculated with Thiobacillus thioparus ATCC 23645 for the removal of H(2)S (BTT) and the other filter with Nitrosomonas europaea ATCC 19718 for the removal of NH(3) (BNE). Three different configurations were studied by modification of the gas line and recirculation medium line. The best results were obtained with the BNE biotrickling filter after the co-immobilization of the two bacteria. A removal efficiency of 100% for 230 ppmv of NH(3) and 129 ppmv of H(2)S was reached at an EBRT of 60 seconds. The results obtained show that it is possible to co-immobilize both microorganisms using the same recirculation medium and remove successfully H(2)S and NH(3) from a gas mixture.