Intensification of Anaerobic Microbiological Degradation of Sewage Sludge and Gypsum Waste Under Bio-Sulfidogenic Conditions

The basic stages of co-processing of sewage sludge and gypsum waste were studied. Bio-chemical equations of wastes detoxification on the final stage of AMD under bio-sulfidogenic conditions were developed. After biosulfidogenic treatment organic complexes with heavy metals were destroyed and formed insoluble compounds of metal sulfides. Thus, heavy metals were transformed into the unavailable form for plants. The effects of ozone pretreatment on the biodegradability of sewage sludge were determined. The use of the sludge pre-treatments prior to the anaerobic digestion process led to higher hydrogen sulfide productions and organic matter removal efficiencies in mesophilic conditions. In ozonation, the highest increase of soluble COD (68%) was achieved. In the anaerobic bioreactor, after 20 days digested the elimination of CODt and CODs varied between 78–84% and 83–87%, respectively, within advanced operation of anaerobic bioreactor. The hydrogen sulfide production after ozonation was 1.67 times higher than that without pre-treatment. The sulfate reduction was 94.5% in system was maintained. The qualitative and the quantitative of composition the gas phase were analyzed. The technological applications efficiency of such system was formed.