A huge amount of organic waste is generated annually around the globe. The main sources of solid and liquid organic waste are municipalities and canning and food industries. Most of it is disposed of in an environmentally unfriendly way since none of the modern recycling technologies can cope with such immense volumes of waste. Microbiological and biotechnological approaches are extremely promising for solving this environmental problem. Moreover, organic waste can serve as the substrate to obtain alternative energy, such as biohydrogen (H₂) and biomethane (CH₄). This work aimed to design and test new technology for the degradation of food waste, coupled with biohydrogen and biomethane production, as well as liquid organic leachate purification. The effective treatment of waste was achieved due to the application of the specific granular microbial preparation. Microbiological and physicochemical methods were used to measure the fermentation parameters. As a result, a four-module direct flow installation efficiently couples spatial succession of anaerobic and aerobic bacteria with other micro- and macroorganisms to simultaneously recycle organic waste, remediate the resulting leachate, and generate biogas.

У доповіді зазначено, що однією з нагальних проблем, які постали сьогодні перед Україною і потребують термінового вирішення, є зменшення імпортозалежності нашої держави в паливній галузі. Установи НАН України мають значний науковий потенціал і накопичили багаторічний досвід з розвитку та впровадження новітніх технологій виробництва, переробки й ефективного використання альтернативних автомобільних палив — біометану, біодизелю, синтетичного моторного палива, а також водню.

The production of biomethane from biogas energy costsfor the most widely used amine and water processes for extracting carbon dioxide from biogas were analyzed using computer simulation. Combined water-amine absorption method of biogas purification from CO₂ wasincluded in the comparative analysis. For the CO₂ content of the biogas from 32 to 42 %, the specific energy costs when using water absorption to extract carbon dioxide from biogas are, on average, in ~ 2.5 times lower than amine absorption, but the loss of CH₄ by water absorption was 7.1–7.6 % due to its watersolubility with practically zero CH₄ loss when using amine absorption and insignificant loss (0.17–2.8 %) using water-amine technology. Using preliminary water absorption of CO₂ saved CH₄ can compensate the power consumption of the biogas compressor or the heatcosts of saturated amine absorbent regenerating. This will allowto reduce energy consumption to almost equal to water absorptionone. The results of simulation of carbon dioxide extraction from biogas can be used to optimize technological absorption schemes for the production of biomethane — an analogueof natural gas. Bibl. 13, Fig. 5, Tab. 6.

The EU countries are implementing biomethane production projects from biogas, supplying it to the natural gas distribution grid, or using it as motor fuel. It is also extremely relevant for Ukraine, supposing the problems with gas import due to Russian aggression. Biogas production from landfills, agriculture waste, and sewage is already implemented in Ukraine, so the next step must be biomethane production on an industrial scale and the selection of biogas separation technology is important. Using 11 years of industrial experience in biogas production from landfills, wide experience of the different methane-containing gases separations, and small companies’ industrial possibilities, the most applicable separation technologies for Ukraine were selected: amine, water, and combined water amine carbon dioxide separation. These technologies had compared using computer simulation with real landfill biogas flow rate debt. Results of a software simulation of the most applicable water-amine absorption technology were verified using a laboratory setup. For carbon dioxide concentration in biogas at 32–42 % vol., the specific energy consumption when using water absorption is on average 2 times less compared to amine absorption, but at the same time, the loss of methane due to its solubility in water during water absorption amounted to 7.1–7.6 %, with practically no losses in amine absorption, and minor losses at 0.17–2.8 % in combined water-amine technology. The energy consumption of combined water-amine absorption is comparable to that of water absorption due to: a) reduction of heat losses for the regeneration process of saturated amine absorbent, as part of carbon dioxide has already been removed with water technology; b) using the methane excess to compensate power consumption of the biogas compressor during the preliminary water absorption of carbon dioxide and/or to compensate heat costs of the saturated amine absorbent regeneration

The main technologies for carbon dioxide capturing are analyzed. Promising technologies include “before burning” CO2 capture and CO2 injection into depleted oil fields to enhance oil recovery, which make it possible not only to reduce residual oil saturation, but also to reduce carbon dioxide emissions into the atmosphere effectively. The energy costs of amine processes for extracting carbon dioxide from biogas are analyzed with the use of computer simulation. To extract carbon dioxide from process gases a traditional single-flow absorption scheme can be used in which MDEAmod absorbents the optimal in terms of energy performance minimizing. The MDEAmod absorbent is universal and can be used in CO2 extraction processes, including those under high pressure, from various process gases, in which the CO2 content can vary over a wide range of concentrations and reach 45 % (vol.). The use of this absorbent reduces the heat consumption for the regeneration of the saturated sorbent by 1.4–2.5 times compared to 18 % MEA and reduces the absorbent consumption by 30 %. A laboratory unit for extracting target fractions of biomethane and carbon dioxide from biogas has been created. The model calculation results of the amine CO2 extracting from biogas and those obtained on a laboratory unit are quite close and the deviation of the calculated from the experimentally obtained CH4 concentration in biomethane at a pressure in the absorber Pabs = 0.11–0.2 MPa does not exceed 3 %. The results of extracting carbon dioxide from biogas modeling can be used to optimize the technological absorption schemes for the production of biomethane - an analogue of natural gas. Experimental technology has been developed and equipment for the production and decomposition of natural gas and carbon dioxide hydrates has been created. The thermodynamic parameters of hydrate formation by bubbling have been determined, and hydrate samples have been obtained. Thermodynamic trend of pressure difference of 1.5–2 MPa to methane replace with carbon dioxide in hydrates was experimentally established and thus the possibility of replacing methane gas hydrates with carbon dioxide and using this technology for the conditions of developing gas hydrate deposits in the Black Sea was confirmed. Bibl. 30, Fig. 10, Tab. 3.