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Natural substrates used in horticultural practice quickly degrade during plant cultivation. Methods to extend their service life are sought using natural materials, the acquisition and disposal of which do not burden the natural environment. The paper presents a sustainable method for modifying the coconut fiber substrate by impregnation with a wood-based isolate activated for polymerization and the addition of biochar pellets with retention-increasing properties. The modifications applied to the substrates were shown to have an impact on some of their physical properties, which directly impacted their usefulness in the horticultural production of dessert raspberries. It was found that after a year of operation, the modified substrates showed significantly lower levels of degradation markers. The shrinkage of the impregnated substrate was ~50% lower than that of the control sample, while the substrate with the addition of biochar pellets resulted in similar shrinkage and the lowest plant root mass (25.47%). The usefulness of these substrates was also verified by measuring the physiological parameters of the plants, which determined the ability to photosynthesize and build biomass, as well as susceptibility to stress potentially caused by substrate modifications. The recorded values of these parameters indicate, in most cases, that there is no disturbance of the homeostasis of raspberry plants grown using these substrates. However, plant productivity (measured by the yield of harvested raspberry fruit) indicates that the use of impregnated coconut fiber substrate with the addition of biochar pellets allows for obtaining the highest fruit yields (fruit yield—2.43 kg plant−1). The yields obtained in combination with the extended durability of the modified substrates during operation recommend this solution for use in horticultural practice and make the production more sustainable. [ABSTRACT FROM AUTHOR]

To improve energy and environmental security in urban environments and in accordance with the requirements of the EU, the task of sustainable developing agriculture in urban agglomerations and monitoring it using satellite images becomes relevant. The aim of the work is the development of methods and means for determining stable islands of thermal energy to substantiate the optimal locations for plant growing practices in the metropolis. The research was conducted in Kyiv, the largest metropolis of Ukraine. Data from the Landsat 8 and 9 satellites were used because of the free data and they have better spatial resolution and an available archive of observation results. It was established that the temperature map of the city of Kyiv shows differences in temperature between different parts of the city, probably due to the presence of different sources of heat radiation. It is obvious that the standard deviation of the temperature in the plots depends on many factors, in particular, the season and the type of land use. It is necessary to find alternative solutions for the development of crop production in this area, taking into account the characteristics of thermal emissions. Based on software products from free satellite monitoring providers, EO Browser, a specialized software solution (web application) has been created for monitoring agricultural plantations in an urban environment. A collection of LANDSAT 8 satellite images was used. Areas with stable heat emissions were found, which are due to the operation of a modern shopping and entertainment center, and non-traditional crops for landscaping adapted to its design are proposed. As a result of research, strong heat emissions were recorded for some objects, for them the temperature exceeds the surrounding area by 4 °C, while the minimum standard deviation in January is 0.5 °C, the maximum in July is 2.8 °C, in April and October—1.7 °C and 1.2 °C, respectively. [ABSTRACT FROM AUTHOR]

The purpose of this work is to substantiate the approach to assessing the state of organic waste generation by households of a given community, which is based on passive production observations and intellectual analysis of statistical data, which ensures consideration of the factors and features of organic waste generation, as well as the development of qualitative models for forecasting their receipt. To achieve the goal, the following tasks were solved: the analysis of the state of organic waste generation by households in the EU countries was performed; an approach to assessing the state of organic waste generation by households of a given community is proposed; based on the use of the proposed approach, and models for assessing the state of organic waste generation of households in a given community were substantiated. The hypothesis of the study is to substantiate and use an approach to assessing the generation of organic waste by households in individual communities, based on the method of association learning and search for association rules, which will identify factors that have a significant impact on the volume of organic waste generated by households, the consideration of which will improve the accuracy of forecasting models and improve the quality of management of the processes of collection and processing of this waste in communities. The research methodology used allows for the use of data mining, probability theory, mathematical statistics, machine learning technology, and the Associative Rule Learning (ARL) method. Based on the use of a reasonable algorithm, they identify key trends and relationships between the factors of organic waste generation in communities in different countries, which is the basis for creating accurate models for predicting the volume of collection and processing of this waste in communities. The study found that the largest number of households produced organic waste per capita in the range of 0.14–0.25 kg/person. At the same time, most households have from two to four residents and are located on the adjoining territory from 350 m2 to 680 m2. Based on the method of learning associative rules, it was found that there are no close correlations between individual factors that determine the daily volume of organic waste generation by households per capita. The highest correlation coefficient between the type of housing and the income level of household residents is 0.13. The number of residents and the occupied area of the adjacent territory have the greatest impact on the daily volume of organic waste generated by households per capita. The substantiated associative rules of relationships, as well as the diagrams of relationships between factors, have helped to identify those factors that have the greatest impact on the volume of organic waste generation. They are the basis for creating accurate models for predicting the volume of collection and planning the processing of this waste in communities. Based on the proposed approach, Python 3.9 software was developed. It makes it possible to quickly carry out calculations and perform a quantitative assessment of the state of organic waste generation by households of a given community according to the specified rules of association between the volumes of organic waste generation and their factors. The results of the study are the basis for the further development of models for accurate forecasting of the collection and planning of the processing of organic waste from households in communities. [ABSTRACT FROM AUTHOR]

This study presents the experimental results obtained from hybrid filtration combustion using biomass pellets. The experiments were carried out using a porous media gasifier filled with pellets and inert material. The gasifying agent used was an air–steam mixture, with 40% being steam. The dependence of the temperature in the gasifier's reaction zone from the volume percentage of inert porous material in the gasifier, the specific heat capacity of this material, as well as the air–steam blowing rate, was investigated. The multifactor experiment method was used. A maximum temperature of 1245 °C was achieved using 28 vol% of porous material with a heat capacity of 1000 J/(kg·°C) and at a blowing rate of 42 m3/h. The maximum hydrogen content in the syngas was 28 vol%. This was achieved at an air–steam blowing rate of 42 m3/h and 40 vol% porous material, with a heat capacity of 1000 J/(kg·°C). The calorific value of the syngas was 12.6 MJ/m3. The highest CO content in the gas was 28 vol% and was obtained at 20 vol% porous material with a heat capacity of 1000 J/(kg·°C) and a blowing rate of 42 m3/h. The obtained information is applicable in the design, management, and control of gas production by way of a hybrid filtration combustion process in a downdraft gasifier. [ABSTRACT FROM AUTHOR]

In European industry, such as metallurgical, mining and processing, construction, food, and chemical, vibration exciters are used, which indicates their wide and, in some cases, unique technological capabilities. The most common are electromagnetic and unbalanced vibration exciters. The advantages of electromagnetic vibration exciters include the ability to control the amplitude of the vibration by changing the electrical power supplied; the disadvantages are high material consumption. However, unbalanced vibration exciters have low energy efficiency, which is associated with difficult start-up conditions and with an overestimated mechanical power of the vibration exciter in relation to the power required by the technology itself, which is due to the need to minimize the effect of the technological load on the operating mode of the vibrating unit. Adjusting the amplitude of the disturbing force of unbalanced vibration exciters, regardless of the vibration frequency, will make it possible to reduce the installed power of the unit by passing the resonant frequency with a minimum disturbing force and compensating for the effect of the process load by means of a closed-loop electric drive. In the course of the study, an analytical description of the interaction of the rotating unbalances located on a common movable platform was obtained. On the basis of these analytical dependencies, a mathematical model was developed that takes into account the dynamic characteristics of a frequency-controlled asynchronous electric drive of a closed-loop control system for the mutual arrangement of rotating unbalances. The simulation results confirmed the possibility of using the specified electric drive to control the oscillation amplitude directly in the process of operation of a four-unbalanced vibration exciter. A physical experiment was carried out to determine the transient processes of changing the angular velocity of an induction motor with an abrupt change in the frequency converter setting. On the basis of this experiment, the previously created mathematical model was refined in terms of describing the dynamic parameters of the electric drive. The proposed structure of the control system, the performance of which has been confirmed by mathematical modeling, makes it possible to implement an adjustable four-unbalanced vibration exciter using single commercially available asynchronous vibrators. [ABSTRACT FROM AUTHOR]

The purpose of this work is to develop a model for balancing the processes of the generation and consumption of electricity, taking into account the random nature of these processes. The subject of the study is hybrid power systems that use traditional and renewable energy sources and have the properties of a local network. Such systems are sensitive to variable generation modes, and the presence of rapid changes in power requires short time intervals. The presence of wind and solar power plants makes it difficult to ensure a balance of power, which increases the need for intermediate energy storage. The research method is a mathematical modeling of random processes of energy consumption and generation, which allows for the analysis of the current power balancing and the obtaining of the integrated characteristics of the state of energy storage and reuse. The unique goal of the study is to take into account the power gradients and the state of charge of the batteries. The results of the study allow for the comparison of the different configurations of the power system in terms of balance, storage needs, and energy loss. It has been shown that the increase in battery capacity and speed limitations are nonlinearly related to the possibilities of energy conservation and the probability of the incomplete use of the capabilities of the energy storage system. [ABSTRACT FROM AUTHOR]

In this work, a study was performed on the influence of the ratio of height to the diameter of the reduction zone of a small-size downdraft gasifier as well as of the fuel fraction sizes on the gas quality (the quality was evaluated for CO content). The ratio of a full side area to the volume of a fuel fraction (SVR) was used as a fuel parameter. The maximum CO concentration was observed when using a small fuel fraction with SVR—0.7–0.72 mm−1 and when adhering to the ratio of height to the diameter of the reduction zone H/D—0.5–0.6. The maximum electric power for gasoline generators (nominal power equaled 4 kW) when using the gas received from the fast-growing hybrid willow biomass equaled 2.4 kW. This power is 37.5% lower than when using gasoline and 7.0% lower than when using the gas received from the hardwood biomass. The emissions of harmful gases into the atmosphere by the gasoline generator engine equaled 0.12–0.14% CO and 24–27 mln−1 CxHy. The emissions were 64.8 times less for CO and 8.5 times less for CxHy when compared with using gasoline. [ABSTRACT FROM AUTHOR]

Raspberry fruits are a valuable source of bioactive compounds. The study used the modification of the substrate (coconut fibre), consisting of the use of various organic and mineral additives, in the soilless cultivation of raspberries. The additives influenced the biosynthesis of bioactive compounds in the raspberry fruits by modifying the sorption properties and the abundance of the substrate. The influence of the additives on the content of polyphenols was determined as well as their profile (UPLC-MS), antioxidant potential (ABTS), vitamin C content, and the activity of selected enzymes that are markers of stress and resistance to abiotic factors. In the study, a significant effect of these additives was observed on the biosynthesis of polyphenols in raspberry fruit. The highest increase in the content of these compounds in relation to the control sample (substrate—100% coconut fibre), namely 37.7%, was recorded in the case of fruit produced on coconut substrate enriched with sheep wool. These fruits were also characterised by a significantly different profile of these compounds. These changes were caused by readily available ammonium nitrogen and free amino acids in the decomposition of proteins contained in the sheep wool. This was confirmed by the recorded content of chlorophyll SPAD in the plant leaves and the activity of selected enzymes, which proves a low level of stress and good condition of the plants. [ABSTRACT FROM AUTHOR]

In the research carried out by the authors, an approach to the assessment of the project environment of technologically integrated "European Green Deal" projects using corn waste was developed, which takes into account the changing project environment, which determines the risk of the specific cost of disposal of corn waste. On the basis of the predicted approach and the established trends of changes in the specific volume of corn food products from its yield, as well as the specific cost of disposal of corn waste from its specific volume under the condition of maintaining the balance of organic carbon in the fields, a computer program in the Python 3.9 language was developed. The program makes it possible to speed up calculations and perform a quantitative assessment of the state of the project environment in certain regions of the implementation of projects of the "European Green Deal" (TIP of the EGD) using corn waste. An approach to assessing the state of the project environment of TIP of the EGD using corn waste is proposed. A block diagram of the algorithm for assessing the state of the project environment was created, which involves the implementation of ten stages. It provides for determining the dynamics of inequality of individual regions in terms of resource potential for the production of clean energy from corn waste according to the Gini index. The Gini index was used to assess three indicators that take full account of the unevenness and dispersion of raw materials in a given area for the production of clean energy. This provides a preliminary assessment of the risks to stakeholders for stakeholders in technologically integrated projects of the "European Green Deal" using maize waste. Based on the proposed approach, a computer program in Python 3.9 was developed. It provides an opportunity to speed up the calculations and perform a quantitative assessment, according to these indicators, of the state of the project environment in some regions regarding the TIP of the EGD. The uneven distribution of raw materials in the territory of Ukraine for the production of environmentally friendly energy from corn waste and the risk of value for stakeholders were assessed. It is established that in the territory of Ukraine there are nine regions (Dnipropetrovsk, Donetsk, Zaporizhzhia, Kirovohrad, Luhansk, Mykolaiv, Odesa, Kharkiv, Chernivtsi), which do not ensure the preservation of the balance of organic carbon in the fields during long-term cultivation of corn. In addition, four regions of Ukraine (Vinnytsia, Poltava, Kherson, Zakarpattia) have an unfavorable project environment in terms of risk. In these regions, the Gini index exceeds the critical value of the three studied indicators. The Zakarpattia region is the most unfavorable for the implementation of the TIP of the EGD. It is established that the minimum material risk for the implementation of technologically integrated projects with the use of corn waste is observed in three regions of Ukraine (Sumy, Rivne, Ternopil). [ABSTRACT FROM AUTHOR]

The gasification rate of fuel, biomass gasification in particular, is an important parameter which is worth considering in the process of creating a gasifier with a continuous operation process. The gasification of biomass is a complex thermochemical process. The theoretical and practical studies of the gasification rate of biomass are complicated because of a high thermochemical rate of reactions in the functioning zones of a gasifier. The complexity of the study prevents the achievement of the required accuracy of the analytical model of the gasification rate of biomass. The known theoretical models of the gasification rate only partially describe the dynamics of the gasification rate of biomass. Moreover, most scientific studies are focused on establishing the effects of gasifier parameters and the gasification process on the quality indicators of the received gas but not on the gasification rate of fuel. To build an accurate model of the gasification rate the authors propose a series of experimental studies in a well-defined range of the parameters of a gasifier. The paper suggests a simple mathematical model of the gasification rate of biomass, which is proportional to the amount of plant biomass that remained non-gasified. The coefficients of the gasification rate for straw pellets, wood pellets and wood in pieces have been determined. Under a minimal air supply into an active zone of a gasifier (0.00088 m3/s) a coefficient of gasification rate is nearly the same for the test fuel materials and it differs by 4.7% between wood pellets and straw pellets. When the air supply increases, the gap between the coefficients increases as well and it reaches 9.44 × 10−5 c−1 for wood pellets, 1.05 × 10−4 c−1 for straw pellets and 8.64 × 10−5 c−1 for wood in pieces under air supply into an active zone of a gas generator of 0.01169 m3/s. Straw pellets have the highest gasification rate and wood in pieces has the lowest gasification rate. [ABSTRACT FROM AUTHOR]

An analysis of the state of affairs in the theory and practice of implementation of technologically integrated projects in various applied fields was carried out. The peculiarities of the implementation of the technologically integrated projects of the "European Green Deal" for the production of ecologically clean fuel from agricultural waste were analyzed. The expediency of developing a method of coordinating the configurations of technologically integrated "European Green Deal" projects for the production of ecologically clean energy from agricultural waste on the territory of a given region, taking into account their specific project environments, was substantiated. As a result of the conducted research, a method of coordinating configurations of the technologically integrated "European Green Deal" projects for the production of ecologically clean energy from agricultural waste in the territory of a given region, taking into account their specific project environment, was developed. This method involves the implementation of five stages, which ensure consideration of the specific design environment of each region and the type of agricultural raw materials for energy production. This method involves the modeling of individual projects, which makes it possible to increase the accuracy of determining their value indicators, taking into account risk. The balancing of the technologically integrated projects of the "European Green Deal" for the production of clean energy from agricultural waste was carried out on the basis of maximizing value for stakeholders and minimizing risk. On the basis of the proposed method, the computer program "Balancing technologically integrated projects" was developed. The use of this computer program for the given project environment (conditions of LLC "Lutsk Agrarian Company" of the Volyn region, Ukraine) made it possible to forecast the specific value and risk of individual projects involving harvesting raw materials from corn waste. The statistical characteristics of the distribution of the projected specific value of the project of harvesting raw materials from corn waste were established: the estimate of mathematical expectation—EUR 9/ton; dispersion—EUR 25/ton; the estimation of root mean square deviation—EUR 5/ton. The technologically integrated projects of the "European Green Deal" for the production of ecologically clean energy from corn waste with the greatest interconnections in terms of value were identified. The ranking of raw material procurement projects from corn waste was carried out according to their specific values and risks. Among the considered projects, priority was given to project #7 and project #1, which provided the greatest values, 37.6% and 36.6%, respectively, of the total value of the considered projects. The obtained results made it possible to establish priority projects and carry out their balancing by value and risk. [ABSTRACT FROM AUTHOR]

Issues of environmental security, fuel and energy independence have been forming political and economic territories for several centuries. Current events in Ukraine have become a litmus test, which clearly highlights the dangers of resource monopolies and the transfer of economic benefits. The issue of ensuring the energy system in climate neutrality became relevant even before the aggression by Russia. However, today, there is no country, it has not recognized that there is the urgent need to develop and implement effective tools for economic development in a sustainable environment. The modern cost-oriented model of knowledge of economic processes has led not only to the irrational use of natural potential. Large-scale use of natural resources and the irrational organization of production (including agricultural) disrupt the process of their reproduction, which, in turn, leads to the depletion of bioresources and, as a consequence, can lead humanity to ecological catastrophe. Certain solutions have been proposed to address these issues. To ensure the efficient use of the resources of the agricultural sector and the reliable reflection of biological processes, it is proposed to recognize the biological form of capital as self-growing and self-reproducing value, which, in the process of biological transformation, allows obtaining an additional unit of benefits. The study examines, in detail, the promising areas of the transformation of the agricultural sector in the framework of a technologically integrated European Green Deal in the EU. In this study, to determine the potential opportunities for the ecological transformation of agriculture, discrete analytical models of the assessment of the agro-industrial complex of Ukraine were used. Representative data use statistical indicators of Ukraine and, to illustrate potential opportunities, present a comparison of export data to EU countries. In addition, it reveals the realized and potential opportunities of Ukraine's entry into the European market through the prism of the implementation programs of EU environmental policy. The place and significance of assimilation potential for a reduction in the anthropogenic impact on the environment, and providing the self-restoration of natural resources, are substantiated. It is determined that one of the most effective tools for low-cost reduction in greenhouse-gas emissions is the national-level implementation of environmental-quota trade and the development of organic production. The study includes an analytical assessment of the expected emission reductions from environmental initiatives' implementation. Prospects for further research are the development of an effective mechanism for the systematic management of the biological potential reproduction of the agricultural sector while reducing anthropogenic impact on the environment. [ABSTRACT FROM AUTHOR]

The combustion of waste biomass is becoming a key challenge for the energy sector, especially in times of growing energy demand and increasing environmental awareness of society. Processing such fuels is usually demanding. Mathematical modeling makes it possible to adapt the course of the process. The best option is to use appropriate fuel mixtures. The aim of this work was to develop a simple model that would allow the pre-selection of the mixture of two types of digestate. Residues from methane fermentation of maize and apple pomace were used in the study. The paper presents both a mathematical model and laboratory tests. The practical part was to check the validity of the model estimates. The model works on the basic data from physicochemical analysis. Laboratory tests included combustion of the samples of different mixtures. We used image analysis of thermograms to determine changes during combustion, which allowed us to determine when and where the main combustion occurs. Results show that a simple mathematical model is able to estimate the course of the combustion of a fuel particle. [ABSTRACT FROM AUTHOR]

The article analyzed the state of the global problem of ecological safety of the EU and argued the need to create a methodology for planning technologically integrated projects of the "European Green Deal" (TIP "EGD") that accounts for the risks to the stakeholders, i.e., the state, project executors, resource suppliers, project managers, and clients. Each of these has an individual set of values that determines the project risk for them. Herein is proposed a taxonomy of three ranks of TIP "EGD" involving agricultural waste, determined by their characteristics, products, and requirements for the stakeholders. The authors point out the need to create tools for quantitative risk assessment for the stakeholders of TIP "EGD" involving agricultural waste and distinguish four groups of risk components with regard to the value of such projects. A model of value risk formation is presented that addresses the risk management of each of these stakeholder values. The need to develop tools (models, methods, and algorithms) for quantitative risk assessment of the values of each type of project is discussed. Regularities in the formation of stakeholder values, which were a foundation of the model of formation, are established. [ABSTRACT FROM AUTHOR]

Biogas production is an important component of sustainable energy management. In addition to energy-rich biogas, this process also generates solid waste in the form of digestate. The management of this stream has been problematic for many years. One promising method of utilizing this fraction seems to be incineration under controlled conditions. This paper presents an analysis of mixtures of different digestates to assess their suitability for incineration. Four digestates based on corn silage CS and apple pomace AP were used as test fuel. The ultimate and proximate analysis showed that this fuel deviates from the standards accepted for pure biomass, but was found in other fuels, especially those treated as waste. This materials can be a valuable source of energy, but combustion needs be undertaken in special units. Moisture content of investigated digestate-type ranges from 11.9–12.2% and ash content ranges from 8.2% to 11.6%. This could lead to ash sintering and slugging problems, which are problematic, especially because it is not designed for such types of fuel boilers. The study showed correlations between the elemental composition and the course of basic combustion processes. The ultimate analysis of all mixtures shows that the shares of major elements looks similar. These results are connected with the thermogravimetric analysis TGA, which shows similar thermal decomposition for all four mixtures. It is valuable information because, in this special case, when we have mixtures of corn silage and apple pomace originated digestates, the changes in the ratio CS:AP will not affect combustion significantly. [ABSTRACT FROM AUTHOR]

The paper presents the results of research aimed at evaluating the possibility of using selected tree leaf species to produce solid biofuels. The possibility of production of qualitative solid biofuels from urban tree leaves meets the expectations of the municipal sector. Collection of tree leaves in urban areas is very often necessary for road safety reasons, the need to collect biomass rich in dust and pollution as well as biomass infested with pests. The production of solid biofuels from tree leaves allows for effective management of this raw material with energy recovery. The performed research indicates such a possibility, and the obtained ash is used as a soil improver. The conducted research showed that the biomass of leaves of five tree species used in the experiment can be a source of raw materials for production of qualitative biofuels. The obtained pellets were characterized by properties comparable to those of classical wood pellets. The lower heating value of the obtained pellets ranged from 14.5 to 15.5 MJ∙kg−1. Physical properties of the obtained pellets described by bulk density (BD 600–660 kg∙m−3), mechanical durability (DU 90–96%), moisture (Mar 10–12.5%) indicate that these products can be used in existing combustion equipment. Preliminary analysis of the obtained ashes (determination of ash melting point, bulk density) indicates that they should not cause difficulties in ash removal systems from the combustion chamber. [ABSTRACT FROM AUTHOR]

Briquetting is one of the recommended biomass agglomeration processes. The material subjected to briquetting gains valuable functional features related to higher energy density, appropriate moisture content, and increased bulk density. However, the briquettes need high mechanical durability to maintain high quality during transportation, loading, and other logistic steps before they will be delivered to the final consumer and utilized for energy purposes. The mechanical durability depends on many factors, including the particles comminution of the compacted biomass. Therefore, the aim of this study was to analyze the impact of particle comminution on the mechanical durability of wheat straw briquettes. The research was carried out in accordance with the international standard for solid biofuels PN-EN ISO 17831-1:2016-02. The briquettes were produced from three different fractions: 0–2 mm, 2–15 mm, and 15–45 mm. To obtain more data related to the mechanical durability of briquettes, the tests were also carried out outside the ISO standard conditions. During the investigations, the working chamber operation time was extended from 5 to 60 min, and the rotational speed of the working chamber was increased to 25 and 30 rpm, respectively. The results indicated that the mechanical durability index (Du) of briquettes decreases along with the increase in the particle size. According to the PN-EN ISO 17831-1:2016-02 standard, the highest mechanical durability was achieved for the 0–2 mm fraction (Du = 91.17%) followed by the 2–15 mm fraction (Du = 88.12%), and the lowest was achieved for the 15–45 mm fraction (Du = 84.48%). It was noticed that the increase in the working chamber operation time resulted in a decrease of the Du value. Moreover, the difference in mechanical durability (between t5 = 5 min and t60 = 60 min) was greater for a larger fraction (∆Du = 16.26% for 0–2 mm fraction, ∆Du = 21.04% for 2–15 mm fraction, and ∆Du = 23.43% for 15–45 mm fraction). It was also observed that the increase of the rotational speed of the working chamber caused a slight decrease in the value of the mechanical durability of briquettes for all investigated fractions. [ABSTRACT FROM AUTHOR]

The process of biomass compaction depends on many factors, related to material and process. One of the most important is the proper fragmentation of the raw material. In most cases, more fragmented raw material makes it easier to achieve the desired quality parameters of pellets or briquettes. While the chipping of biomass prefers moist materials, for grinding, the material needs to be dried. As drying temperature changes the properties of the material, these may affect the grinding process. The aim of this work was to determine the influence of the drying temperature of biomass raw material in the range of 60–140 °C on the biomass grindability. To only determine this effect, without the influence of moisture, grinding was carried out on the material in a dry state. The research was carried out on a mill with a knife and hammer grinding system, which is the most popular in the fragmentation of biomass. The analysis of particle size distribution and bulk density of the obtained material was carried out. The energy demand for the grinding process was determined and it was shown that drying temperature, grinding system, and mainly type of biomass affects the grindability. [ABSTRACT FROM AUTHOR]

For biomass compaction, it is important to determine all aspects of the process that will affect the quality of pellets and briquettes. The low bulk density of biomass leads to many problems in transportation and storage, necessitating the use of a compaction process to ensure a solid density of at least 1000 kg·m−3 and bulk density of at least 600 kg·m−3. These parameters should be achieved at a relatively low compaction pressure that can be achieved through the proper preparation of the raw material. As the compaction process includes a drying stage, the aim of this work is to determine the influence of the drying temperature of pine biomass in the range of 60–140 °C on the compaction process. To determine whether this effect is compensated by the moisture, compaction was carried out on the material in a dry state and on the materials with moisture contents of 5% and 10% and for compacting pressures in the 130.8–457.8 MPa range. It was shown that drying temperature affects the specific density and mechanical durability of the pellets obtained from the raw material in the dry state, while an increase in the moisture content of the raw material neutralizes this effect. [ABSTRACT FROM AUTHOR]

Increasing production of waste has compelled the development of modern technologies for waste management. Certain fractions of municipal solid wastes are not suitable for recycling and must be utilised in other ways. Materials such as refuse-derived fuel (RDF) fractions are used as fuel in cement or CHP (combined heat and power) plants. The low bulk density leads to many problems pertaining to transportation and storage. In the case of biomass, these problems cause reduction in pelletisation. This paper therefore presents a comprehensive study on RDF pellet production, which is divided into three major areas. The first describes laboratory-scale tests and provides information on key factors that affect pellet quality (e.g., density and durability). Based on this, the second part presents a design of modified RDF dies to form RDF pellets, which are then tested via a semi-professional line test. The results show that RDF fraction can be compacted to form pellets using conventional devices. Given that temperature plays a key role, a special die must be used, and this ensures that the produced pellets exhibit high durability and bulk density, similar to biomass pellets. [ABSTRACT FROM AUTHOR]

Raspberry fruits are a valuable source of bioactive compounds. The study used the modification of the substrate (coconut fibre), consisting of the use of various organic and mineral additives, in the soilless cultivation of raspberries. The additives influenced the biosynthesis of bioactive compounds in the raspberry fruits by modifying the sorption properties and the abundance of the substrate. The influence of the additives on the content of polyphenols was determined as well as their profile (UPLC-MS), antioxidant potential (ABTS), vitamin C content, and the activity of selected enzymes that are markers of stress and resistance to abiotic factors. In the study, a significant effect of these additives was observed on the biosynthesis of polyphenols in raspberry fruit. The highest increase in the content of these compounds in relation to the control sample (substrate-100% coconut fibre), namely 37.7%, was recorded in the case of fruit produced on coconut substrate enriched with sheep wool. These fruits were also characterised by a significantly different profile of these compounds. These changes were caused by readily available ammonium nitrogen and free amino acids in the decomposition of proteins contained in the sheep wool. This was confirmed by the recorded content of chlorophyll SPAD in the plant leaves and the activity of selected enzymes, which proves a low level of stress and good condition of the plants.