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The rising demand for food products and subsequent increase in agricultural production leads to heightened quantities of waste and by-products, particularly within the livestock industry. Traditional methods of livestock by-product disposal encompass intensive processing, including biodestruction processes. However, these processes tend to generate significant emissions of climate-active gases such as carbon dioxide, methane, nitrous oxide, and ammonia. To mitigate environmental impacts, it is proposed to integrate an advanced gas-air emission purification system into the existing livestock by-product processing lines. (Research purpose) The objective is to develop a system for purifying emissions of climate-active gases, particularly ammonia, produced during the intensive biotechnological processing of livestock by-products. (Materials and methods) Based on the properties of the primary pollutants, possible methods for their removal from emissions were determined. Such methods include dry, wet, condensation, and biological treatment. The biopurification method was selected for its efficacy and optimal performance. (Results and discussion) As a technical solution, a sequential gas-air emission purification process was developed using biofilters equipped with a polymer carrier and organic substrates as fillers. The system is equipped with digital sensors for monitoring and controlling the operational workflow. A special feature of the proposed system design is the use of replaceable filter cartridges and an active irrigation system. (Conclusions) The research helped to identify main types, parameters and methods for purifying emissions of climate-active gases with a focus on ammonia. Emission purification with a digital workflow control system is carried out sequentially in a shell-and-tube condenser and a biofilter. The specific cooling surface is 1.09∙10–3 square meters per 1 cubic meter, the specifi c refrigerant consumption is 0.7 liters per 1 cubic meter. Optimal biofilter performance was attained at the temperature of 30 degrees Celsius, with 45-55 percent humidity, active acidity of 8-8.4 units, and residence time of 15-30 seconds in the filter layer. These conditions ensure a high degree of ammonia purification and long-term biofilter operation.

To calculate methane and nitrous oxide emissions in livestock farming requires the characteristics of produced manure and its treatment systems per a single farm and the whole region. The study aim is to specify the percentage of cattle manure processing technologies in different natural and climatic conditions of the Russian Federation and to revise the emission factor of greenhouse gases. The survey of cattle complexes established the type and amount of manure produced with a breakdown by moisture content and storage volumes. The study calculated the mass of manure processed according to the applied processing technologies. The study acquired the data on the types of manure collection and storage systems and revealed their ratio by federal districts, in more detail – in the federal subjects with bigger stock of dairy cattle. The obtained ratios allowed adjusting the coefficient required to calculate methane and nitrous oxide emissions. The coefficient reflected the share of emitted nitrogen treated or processed by a certain technology. The study calculated the emissions for cows and cattle (without cows) with the use of the adjusted coefficient and the methods of the Intergovernmental Panel on Climate Change for the Northwestern Federal District, which featured the greatest difference between the indicators from the National Inventory and the data obtained in the study. Direct nitrous oxide and methane emission in this District in terms of CO2-eq. according to the Inventory data (2021) was 180.7 thousand t/year; when calculated by the basic distribution of technologies (2021) – 388.7 thousand t/ year; when calculated by the forecast distribution of technologies (2025) – 375.8 thousand t/year. The study results demonstrated that the current tendency to upgrading the manure processing technologies towards the most environmentally friendly and compliant with the principles of best available techniques resulted in reduction in greenhouse gas emissions.

Introduction. Recently the issue of decentralised (autonomous) power supply of certain rural consumers has been increasingly considered. Various small power generators using local and renewable energy sources can be applied for this purpose. So a consumer must choose the best-suited energy-generating source. Materials and Methods.The findings of energy audits, which were conducted by the Institute from 2003 to the present day, were used to evaluate energy consumers and determine operation modes of equipment and load schedules. Complex index of the negative impact of heat and electricity generation on the environment was determined using the Spesivtsev ‒ Drozdov method of logical-linguistic modelling based on expert assessments. Results. Energy sources can be divided into traditional (diesel generators and gas generator plants) or renewable ones (wind turbines, solar collectors, mini hydro systems). Energy source is chosen either with the help of the economic criterion, being the cost of one k·Wh of energy or the criterion of environmental compatibility, or total specific emission of pollutants from energy generation at local generating sources (g/k·Wh). Here, not only the quantity of emissions, but also the harmful effect on the environment is considered. Discussion and Conclusion. For the choice of energy supply sources, the coefficient of energy-ecological compatibility is proposed, being the product of the cost of one k·Wh of energy generated and specific emission of pollutants. The optimal value of this factor is the smallest, which accounts for both economic and environmental feasibility of energy generating sources.