Microbial removal of NOx at high temperature by a novel aerobic strain Chelatococcus daeguensis TAD1 in a biotrickling filter

摘要

The removal of NOx at high temperature by Chelatococcus daeguensis TAD1 in a biotrickling filter was studied. Media components of the recycling liquid were screened using Plackett-Burman design and then were optimized using response surface methodology, which enhanced the efficiency of nitrate removal by TAD1. The optimal medium was used to perform long-term experiments of NO_x removal in a biotrickling filter under high concentrations of O_2 and NO in simulated flue gas. Results showed that the biotrickling filter was able to consistently remove 80.2-92.3% NO_x when the inlet NO concentration was 600 ppm under the conditions of oxygen concentration ranging between 2% and 20% and empty bed residence time (EBRT) being 112.5 s. Analyses by polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) indicated that TAD1 was always predominant in the biofilm under a flue gas environment. Overall, the present study demonstrated that utilizing a biotrickling filter inoculated with the aerobic denitrifier TADl to remove NOx at high temperature was practically feasible.