Influence of Bacillus subtilis and Pseudomonas aeruginosa BSW and Clinoptilolite Addition on the Biowaste Composting Process

This work aimed the influence of inoculation of Pseudomonas aeruginosa BSW, Bacillus subtilis and zeolite on a biowaste composting process. The composting process of biowaste was conducted without (experiment P1) and with (experiment P2) inoculation of selected bacteria and zeolite. The addition of 4% of zeolite into biowaste displayed the retention of ammonium in composting material. In experiment P2, the emission of ammonia (147 mg kgVM-1) was about four times less than in experiment P1 (509 mg kgVM-1). The concentration of NH4+ ions in composting material and in condensate in P1 was 924 mg dm-3and 6588 mg dm-3 and in P2 9 mg dm-3 and 91 mg dm-3, respectively..The volume of produced leachate and the concentration of NH4+ ions in leachate in P1 was 150 cm3 and 1266 mg dm-3 and in P2 75 cm3 and 9 mg dm-3, respectively. Toxicity Impact Index (TII50) of leachate in P1 and in P2 was 90.1 and 5.4, respectively, which indicated that P1 was extremely toxic leachate. The obtained conversion of composting material in P1 and P2 was 64% and 71%, respectively, which shows that inoculated bacteria accelerated biodegradation process. Degradation of biowaste during composting was described as first-order process, and kinetic parameter k0 and reaction enthalpy were estimated for P1 and P2 [k0 (P1 and P2) =0.021 +/- 0.001 d-1, Hr (P1 and P2) = 2660 +/- 26 kJ kgvs-1].