TWO STAGE DIGESTION OF FOOD WASTE

• Дата: 2022
• Автори та афіліації: H. Chetveryk — Institute of Renewable Energy of NAS of Ukraine, senior researcher, PhD
• Ключові слова: keywords
• Автор: Chetveryk, H.
• Формат: Стаття
• Мова: Українська
• Опубліковано: Institute of Renewable Energy National Academy of Sciences of Ukraine 2022
• Теми: biogas; organic substrates; food waste; digestion; methane potential
• Онлайн доступ: https://ve.org.ua/index.php/journal/article/view/350
• Назва журналу: Vidnovluvana energetika

The Cabinet of Ministers of Ukraine approved the National Waste Management Strategy until 2030. In this regard, the processing of biodegradable waste, including food waste, using controlled biotechnological processes, in which organic substances are transformed into biogas, is relevant. The article is devoted to determining the methane potential of food waste during its digestion in two stages and specifying the mathematical model of the dynamics of biogas yield. A test was performed to determine the methane potential of food waste under the condition that the process of anaerobic methane digestion was divided into two stages - hydrolysis and methanogenesis. The methane potential of food waste was assessed. The mathematical model of the dynamics of biogas yield was refined, taking into account the obtained experimental data, which made it possible to determine the duration of the hydrolysis stage, the duration of the methanogenesis stage, the biogas potential of the organic substrate, and the intensity of biogas yield. The main problem solved in this study was to ensure the stability of biogas output under the condition of rapid decomposition of organic matter during the digestion of food waste. The problem was solved by dividing the digestion process into two stages. This is explained by the fact that in this way the degree of inhibition of the methanogenesis process by decomposition products at the stage of hydrolysis decreased. The practical significance of the obtained results lies in their use for the design of industrial biogas stations, complexes or plants in which food waste is digested. The duration of the stages for digestion of food waste makes it possible to determine the ratio between the volume of hydrolysis and methanogenesis reactors for industrial biogas plants. It was found that for the continuous mode of digestion of food waste, the volume of the container for storing the prepared daily loading dose and the hydrolysis reactor are the same. The yield of methane from a unit of the initial value of organic matter of food waste was estimated. It is shown that food waste is a promising organic substrate for obtaining biogas. In Ukraine, up to 500 million tons of waste is generated annually, a significant part of which is food waste from 35% to 49% with an organic matter content of 20% to 25%. The biogas potential of food waste is more than 500 m3 of biogas from a ton of organic matter. Bibl. 20, tabl. 6, fig. 2.