CONTINUOUS DECOLORIZATION OF BLEACHED KRAFT EFFLUENTS BY CORIOLUS-VERSICOLOR IN THE FORM OF PELLETS

Continuous decolorization of kraft black liquor by mycelial pellets of Coriolus versicolor in the presence of glucose as co-substrate is discussed. A linear relationship was developed between the rate of decolorization and the liquor concentration. The rate constant was equal to 0.0096 1 gmyc-1 h-1 at 22-degrees-C. During the continuous experiments the pellets exhibited no apparent loss of activity when the liquor concentration was in the range of 400 CU l-1 to 5000 CU l-1. However, in the repeated batch experiments a loss of activity was observed which was dependent on the initial liquor concentration. The half-life of pellets was equal to 4.7, 9.4 and 20.2 days for the initial liquor concentration of 1380, 31780 and 6990 CU l-1, respectively. The production of the extracellular enzyme, laccase, was followed but could not be used as an indicator of the ligninolytic activity. The involvement of the intracellular enzymes of C. versicolor in the decolorization process is described.