Opolinskyi I. Improvement of the organic waste utilization technology by anaerobic digestion with substrate pre-destruction

The dissertation is devoted to solving the actual scientific and practical task of study of dependencies and regularities of influence of various factors on the process of intensification of bioenergetic transformation of biomass of organic waste in biogas. The most important scientific and practical results obtained during the implementation of the tasks set in the work: The mathematical model of fermentation of an organic substrate using the law of active masses, the Arrhenius equation and Weibull distribution for the influence of the destruction of substrate particles on the rate of biogas production has been developed. The proposed model differs from those known in that it takes into account the dimensions of biomass particles and their change in the process of destruction. It allows to determine the influence of the process of destruction of biomass particles of the substrate and their size on the formation of biogas, and also to take into account the influence of degradation parameters on the rate of methanogenesis. It has been experimentally proved that the pre-treatment of the organic waste substrate mechanically increases the biogas output by 24%, and with the addition of hydrogen peroxide (up to 30%) by 38%. The dependence of the biogas output on the ratio of "oxidant:substrate" has been obtained and it has been proved that the maximum productivity of biogas production is achieved by adding 30% of the treated substrate to total biomass in the process of fermentation. It has been determined that the content of ODM and lignin affects productivity, which increases to 38%, while the time of anaerobic digestion decreases from 14-18 to 12-14 days. Verification of the Conto model was carried out on the basis of data from experimental studies of methane digestion of organic waste. On the basis of experimental data on the biogas output during the utilization of rapeseed waste with preliminary treatment with hydrogen peroxide, the expected reduction in greenhouse gas emissions, in terms of the equivalent of carbon dioxide, has been determined. The methodology of calculating the ecological and economic substantiation of the implementation of anaerobic digestion technology of waste and sewage with the production of biogas for the enterprise is developed, which can be used to assess the feasibility of implementation of biogas station and the application of technologies for increasing the productivity of existing biogas station. In order to justify the feasibility of using anaerobic fermentation technology for organic waste, the amount of biogas generated from waste was calculated. Based on the experimental data, the biogas output is up to 0,3 cubic meter per cubic meter substrate and up to 0,5 cubic meter per cubic meter with pre-treatment with hydrogen peroxide.