Screening and Identification of Trioxane（TOX） Degradation Bacteria and Bioaugment on Polyoxymethylene（POM） Wastewater

Abstract:

A strain of s-Trioxane degrading bacterium was isolated from the sediment of Polyoxymethylene wastewater treatment plant，and identified to be Bacillus methylotrophicus by 16S rDNA sequence analysis. The optimum culture conditions of the strain were at about pH 7 and 30 ℃，and the threaholds of maximal tolerable concentrations for NaCl and TOX were 3% and 1 200 mg/L，respectively. In order to detect its degradation characteristics，the strain was mixed together with formaldehyde degrading bacteria，Candida maltosa and Pseudomonas putida，to form multiple strains to treat POM wastewater at the laboratory scale. The treatment results according the order of final effluent quality were：single strain + formaldehyde degradation group > formaldehyde degradation group > single strain group > control group. In single strain + formaldehyde degradation group，the degradation rates of COD，formaldehyde and TOX were 92.80%，96.52 and 95.88%，respectively，which had much better consequences than other groups. There is a synergistic effect of the degrading bacteria combination，which could be used as multiple strains for bioaugmentation treatment of POM sewage.