RESPIRATORY ACTIVITY OF BIOFILMS - MEASUREMENT AND ITS SIGNIFICANCE FOR THE ELIMINATION OF N-BUTANOL FROM WASTE-GAS

A reaction chamber was developed to determine the respiratory activity of microorganisms immobilized on various support materials for waste gas treatment. The volumetric respiration rate was identified as a sui table parameter for estimating the degradative activity of waste gas t reatment plants. A laboratory trickle-bed reactor was filled with eith er granular clay, polyamide beads, or sintered styrofoam. n-Butanol wa s used as model solvent to determine the efficiency of its elimination from the gas phase. This crucial parameter was correlated with the vo lumetric degradation rate, determined from the overall material balanc e under steady-state operating conditions. The volumetric respiration rate of n-butanol was determined with the reaction chamber, and exceed ed the volumetric degradation rate of n-butanol determined from the re actor 16- to 26-fold, depending on the support material. The respirati on rate was correlated to the degradation rate by the stoichiometry of n-butanol oxidation and a correlation factor of 2.6-4.3. The volumetr ic respiration rate appeared to be a suitable parameter to determine t he degradative activity of the trickle-bed reactor used. The volumetri c respiration rate can be ultimately applied to estimate the efficienc y of elimination of an organic pollutant and to calculate the dimensio ns of a reactor required to eliminate a given organic load from waste gas.