VARIABILITY OF CONCENTRATION OF XENOBIOTICS AND MICROBIOCENOSIS IN COMPOSTING SUBSTRATE "MUNICIPAL SOLID WASTE + ACTIVATED CARBON"
The results of experimental studies on the physicochemical and microbiological transformation of the compostable substrate «Solid waste (MSW) + activated carbon» depending on the stage of composting phases development are presented. The temperature of development of the compostable substrate: 17-20 °C (lag phase); 25-30 °C (mesophilic phase, maturation phase); to 60 °C (thermophilic phase). To improve aeration, the compostable substrate was stirred every 10-15 days. To maintain humidity at the level of 50-55 % after 48-72 hours (after each mixing), sterile distilled water of room temperature in the amount of 10-20 ml was added.according to the results of chemical analysis, it was determined that the transformation of xenobiotics in the compostable substrate has a General pattern, manifested in an increase in the concentration of xenobiotics in the three initial stages of development (lag, mesophilic, thermophilic) and up to 90-99 % of their reduction in the maturation stage. In General, the proposed method helps to reduce the concentration of all xenobiotics, to a lesser extent mercury, cadmium and formaldehyde. The proposed method of composting MSW collected in bulk contributes to a significant reduction in the content of the studied xenobiotics in the Mature phase. Cadmium, formaldehyde and mercury are more difficult to remove. Reduction of cadmium and formaldehyde is observed in Mature compost, but exceeds MPC. And only the residual mercury content is better in the thermophilic zone than in Mature compost, but also exceeds the MPC. Production of bioremediation compost is optimal when using activated carbon in the amount of 150 g / kg of solid waste, which allows for disinfection and a maximum reduction in the concentration of xenobiotics.