Kovalenko V. Electrophysical methods for increasing the efficiency of biogas technologies.

Dissertation for obtaining the scientific degree of the doctor of technical sciences in speciality 05.14.08 – Transformation of renewable energy. Renewable Energy Institute of the National Academy of Sciences of Ukraine. Kyiv, 2019. The dissertation deals with the important scientific and technical problem of increasing the energy efficiency of production and consumption of biogas mixtures by using electrophysical influence on the course of these processes. The purpose of the dissertation is to develop the basic scientific provisions for improving the energy efficiency of the processes of production and consumption of biogas mixtures with appropriate equipment in the conditions of industrial enterprises by applying electrophysical methods of influence. Scientific bases have been developed and basic principles of the process of electrophysical influence on biogas technologies in the part of production and use of biogas mixtures have been substantiated, which allowed to increase their energy efficiency. The influence of fields of various kinds on the process of intensification of biogas evolution at different substrate temperatures, mixing modes and field values has been proposed and confirmed, which has led to an increase in the overall efficiency of biogas plants. The optimum level of tension of a constant electric field at which maximization of gassing is observed is established, and the special device which performs the function of effective mixing of the substrate, provides the uniformity of the field in the volume of the bioreactor and creates optimal conditions for the development of microorganisms, which allowed cytolynovitis to be reduced to increase the degree of destruction of dry organic matter and increase the specific output of methane per unit of substrate. Theoretical bases of application of electric fields for control of processes of formation of heat flows and heat distribution inside the chamber of heating devices have been developed, which allowed to use low-calorie biogas mixtures as primary fuel while maintaining the set temperature regime and without going beyond the economic feasibility of switching to energy. The methodology and scheme of multistage treatment of biogas mixture on a parallel principle have been developed, which opens the possibility of obtaining the required quality of fuel by controlling the consumption of biogas at each stage of purification and enrichment with the minimum required power of the corresponding equipment, and the possibility of regulating the chemical composition of biogas on a wide range, depending conditions. A mathematical model of heat distribution inside a heating installation under the influence of a spatial electric field was created, which made it possible to propose a method of heat treatment of metal in chamber furnaces with periodic action using electric fields, and an algorithm was developed to determine the feasibility of using biogas mixtures for a certain range of consumers in industrial environments taking into account environmental requirements and operating restrictions Key words: biogas, substrate, bioreactor, electric field, energy efficiency, heating installation, industrial plant