The article presents the types and classification of waste from the phosphorus industry of the Zh... more The article presents the types and classification of waste from the phosphorus industry of the Zhambyl region of the Republic of Kazakhstan. Waste is classified by its use as recyclable materials for construction materials. The results of a comparative assessment of the physical, chemical and structural properties of the phosphorus industry waste are presented. The article shows that all studied types of waste have astringent properties and can be used as building materials. In this work, a study of the properties of large-tonnage wastes of the phosphorus industry was carried out: 1) electrothermophosphoric granular slag (granulated slag); 2) phosphogypsum; 3) overburden. A technology has been developed for producing non-fired binders from waste of the phosphorus industry and a methodology for designing the composition of raw mixtures of multicomponent building composites has been proposed. Pilot tests and calculation of technical and economic indicators have been carried out, which...
2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON), 2020
The power consumption for building cooling continues to increase due to higher indoor microclimat... more The power consumption for building cooling continues to increase due to higher indoor microclimate requirements and rising outdoor temperatures in summer period. However, the information on real room cooling requirements in Latvia is not currently listed and it is a blind spot when planning solutions for energy efficient cooling system. Therefore, the article presents the methodology for determination of power for cooling purposes in educational building by using hourly power consumption data and regression models.
In this article, work was carried out to study the chemical, mineralogical composition and toxico... more In this article, work was carried out to study the chemical, mineralogical composition and toxicological properties of waste (phosphogypsum, phosphorus slags, overburden) of the phosphorus industry, the optimal content of the grain composition of gravel-sand mixtures in the composition of road mixtures (crushed stone, sand-gravel, sand) and structures of the Zhambyl region of the Republic of Kazakhstan. The possibilities of using slag-mineral mixtures in the year - round construction of highways were studied on the basis of a comprehensive study of the physicochemical processes of hardening and the formation of the structure of slag-mineral materials at negative temperatures. Technological regimes for the construction of roads of various technical categories from slag binding materials, reformed after long-term freezing, have been established. New, unparalleled, binding road mixtures have been created to increase the utilization of waste from the phosphorus industry and expand the r...
Carbon neutrality in municipalities can be achieved by combining individual heating and district ... more Carbon neutrality in municipalities can be achieved by combining individual heating and district heating solutions involving the use of renewable energy sources. Each approach has advantages and disadvantages, but the best solution depends on the specific circumstances of each municipality. As an environmentally friendly and efficient energy use, a decentralised heat supply contributes to achieving energy conservation and emissions reduction goals. Decentralised energy use, such as solar collectors with thermal energy storage or biomass as a resource, reduces dependence on centralised heat generation and transmission. The appropriate infrastructure for connection to district heating networks has not yet been built. On the other hand, it is easier to make investments to construct proper infrastructure in the case of large-scale centralised heat supplies. Moreover, a centralised heat supply with renewable energy sources can provide more inhabitants with renewable heat energy. Within t...
ENVIRONMENT. TECHNOLOGIES. RESOURCES. Proceedings of the International Scientific and Practical Conference
Global trends in the world are currently representing a serious incentive to bring ‘green thinkin... more Global trends in the world are currently representing a serious incentive to bring ‘green thinking’ to life. This is the case of replacing synthetic materials derived from fossil resources with natural-origin, renewable resources. In the automotive industry and other segments of the manufacturing industry, increasing attention is being paid to the use of natural fibers in the manufacturing of composite materials. For example, flax and hemp fiber, as reinforcing material, is starting to widely replace carbon fiber. It is not just an ecological benefit, but also an important product protecting human health, since the amount of emissions that pollute the environment is minimized. Consequently, that lead to reduced intake by human being of harmful substances that would affect its health status. Existing composite materials used in motor vehicles, produced from carbon fibers, are creating very sharp fracture areas in the event of accidents causing human injury, while materials from natur...
Due to the rising demand for food and feed, agricultural waste increases, while plastic pollution... more Due to the rising demand for food and feed, agricultural waste increases, while plastic pollution increases due to hostile human activities. The sustainable way to utilize agricultural waste and promote the bioeconomy concept is to produce an alternative product of plastic, i.e., ‘bioplastic’. This paper used different keywords to perform the bibliometric analysis of the scientific publication related to bioplastic, agricultural waste, and sustainability. Remarkably, results show the increasing research interest in bioplastic with the key developing trends in sustainable bioplastic production, agriculture waste management, biopolymer, and biological processes. The identified developing trends can be used for further research to create a sustainable agricultural sector and produce higher added-value products. Moreover, this study discovered that the agro-biopolymer area needs more focus on sustainable development considering the economic, social, and environmental dimensions.
2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)
The aim of the circular economy is to maximize the value of a product during its use, using secon... more The aim of the circular economy is to maximize the value of a product during its use, using secondary raw materials to create new products. This research focus on the possibilities of using waste as an energy resource - both the aspects of waste recovery, from the point of view of reducing the amount of landfilled waste, and the extraction and further efficient use of landfill gas. In this case the TOPSIS analysis method was used, five alternatives were selected - waste as an energy resource, which was evaluated based on four criteria: technological, economic, social, as well as environmental and climate aspects. The results of ranking energy recovery methods from waste using the TOPSIS method clearly show that the most optimal of the selected alternatives is the use of biodegradable (organic) waste for biogas production. This opens up opportunities for biofuels to be applied in road transport.
This analysis aims to identify the potential of bio-diplomacy focused on forestry resources in La... more This analysis aims to identify the potential of bio-diplomacy focused on forestry resources in Latvia. As the resources are scarce, small states must calibrate their foreign policy to gain a global vision by offering strategic products or services. In order to identify this potential, there are employed the Analytic Hierarchy Process (AHP) and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) analytical methods. The results indicate that economy, climate and environmental and social factors are the most important elements to be considered. The most important driving forces for using forestry resources for bio-diplomacy are demand, volume and renewal.
2019 IEEE 60th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON), 2019
The research focuses on evaluating the impact of large manufacturing enterprises both on country&... more The research focuses on evaluating the impact of large manufacturing enterprises both on country's economy and on environment from the perspective of energy intensity. The case study is based on the situation in Latvia. The research uses the Kaya identity to show the situation that is necessary to obtain in order to achieve the carbon emissions goals of the European Union. The research also provides an analysis on coincidences between Latvia's GDP, energy intensity and carbon intensity, as well as studies the input of the largest industries in Latvia on the country's energy intensity and provides suggestions for improving the manufacturing industry from the perspective of energy savings.
Within the framework of the study a case study is performed, the data provided by a Latvian texti... more Within the framework of the study a case study is performed, the data provided by a Latvian textile production company on their electricity and natural gas consumption, as well as production volumes over a three-year period have been analysed. The specific indicators of electricity, natural gas and CO2 emissions have been calculated and the obtained results are shown in graphs. The correlation of specific indicators with production volumes was analysed by correlation coefficient and linear regression methods. An analysis of statistical data for the calculated specific indicators over a three-year period has been performed. The obtained results show high seasonality of natural gas consumption and close connection between electricity consumption and production volumes.
During the experimental research, an algorithm was developed as a guide for the introduction of s... more During the experimental research, an algorithm was developed as a guide for the introduction of solar panels (PV) in centralized heat supply (CHS) companies and a SWOT analysis of the developed algorithm action blocks was performed. SWOT analysis was carried out for a project implemented in practise and, as a result of which the centralized heat supply system uses solar power with a total capacity of 30 kW. We found that in Latvia, the areas that are suitable for solar panels are several times higher than those required by the systems. Main tasks of the work: to analyse and study available literature and information on solar PV integration into CHS; analyse available solar PV power generation equipment and technologies; develop a roadmap for easy and understandable deployment of solar panels in the company.
Solar technologies are flexible and can be used for both centralized and decentralized energy pro... more Solar technologies are flexible and can be used for both centralized and decentralized energy production. The main aim of this article is to compare different solar technologies and configurations for integration into the DH system. The multi-criteria analyses method is used to rank different alternatives based on several criterions. The evaluation of criterions has been based on previous studies conducted. The multi-criteria analyses allow to compare different solar system alternatives that cannot be compared directly due to differences in their scale, type of energy produced and consumed, investment levels, etc. For the particular DH system researched, the most desirable solution is the PVT panel integration with an area of 1000 m2 which is aligned with the actual DH company’s power consumption. However, the results are strongly impacted by the assumed investment levels, efficiency of the technologies and other assumptions that could be further analysed by the help of sensitivity ...
One of the main pollution types is air pollution, which has a significant impact on the surroundi... more One of the main pollution types is air pollution, which has a significant impact on the surrounding environment and on living beings. Major source of air pollution is combustion processes. There are many flue gas treatment technologies around the world. In this paper a new, innovative flue gas treatment technology – fog unit – is introduced. The goal of the fog unit is to treat flue gases that are emitted from households. In the European Union, including Latvia, at the beginning of 2020, a directive will come into effect that will set limits for emissions and the effectiveness for incinerators in households. The main focus of this study was to determine the most optimal operating mode for the fog unit by changing different operating parameters: sprayed water temperature, sprayed water flowrate and types of nozzles (drop diameters). Results show that the most optimal operating mode in terms of flue gas treatment efficiency and recovered energy is at water temperature: 20 °C, sprayed ...
Aquaculture is currently the fastest growing food-producing sector in the world. The growth of th... more Aquaculture is currently the fastest growing food-producing sector in the world. The growth of this industry has been rapid for the last 25 years, however, aquaculture still relies heavily on feed input from wild capture fisheries. Landings in wild capture fisheries have been stagnant for the last two decades; therefore, new alternatives for conventional fish meal and fish oil need to be found. In this review, various alternatives are described and their advantages and disadvantages are evaluated. Single cell oils (SCO) and single cell proteins (SCP) produced by microorganisms are recognized as the alternative with the most potential for replacing fish meal and fish oil in aquacultures. However, production costs of SCOs and SCPsare still higher than production costs of Omega-3 rich oils from other sources (wild capture, plant derived oils and genetically modified plants); therefore, currently used substrates need to be replaced with cheaper agriculture and industrial biomass residue...
The article presents the types and classification of waste from the phosphorus industry of the Zh... more The article presents the types and classification of waste from the phosphorus industry of the Zhambyl region of the Republic of Kazakhstan. Waste is classified by its use as recyclable materials for construction materials. The results of a comparative assessment of the physical, chemical and structural properties of the phosphorus industry waste are presented. The article shows that all studied types of waste have astringent properties and can be used as building materials. In this work, a study of the properties of large-tonnage wastes of the phosphorus industry was carried out: 1) electrothermophosphoric granular slag (granulated slag); 2) phosphogypsum; 3) overburden. A technology has been developed for producing non-fired binders from waste of the phosphorus industry and a methodology for designing the composition of raw mixtures of multicomponent building composites has been proposed. Pilot tests and calculation of technical and economic indicators have been carried out, which...
2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON), 2020
The power consumption for building cooling continues to increase due to higher indoor microclimat... more The power consumption for building cooling continues to increase due to higher indoor microclimate requirements and rising outdoor temperatures in summer period. However, the information on real room cooling requirements in Latvia is not currently listed and it is a blind spot when planning solutions for energy efficient cooling system. Therefore, the article presents the methodology for determination of power for cooling purposes in educational building by using hourly power consumption data and regression models.
In this article, work was carried out to study the chemical, mineralogical composition and toxico... more In this article, work was carried out to study the chemical, mineralogical composition and toxicological properties of waste (phosphogypsum, phosphorus slags, overburden) of the phosphorus industry, the optimal content of the grain composition of gravel-sand mixtures in the composition of road mixtures (crushed stone, sand-gravel, sand) and structures of the Zhambyl region of the Republic of Kazakhstan. The possibilities of using slag-mineral mixtures in the year - round construction of highways were studied on the basis of a comprehensive study of the physicochemical processes of hardening and the formation of the structure of slag-mineral materials at negative temperatures. Technological regimes for the construction of roads of various technical categories from slag binding materials, reformed after long-term freezing, have been established. New, unparalleled, binding road mixtures have been created to increase the utilization of waste from the phosphorus industry and expand the r...
Carbon neutrality in municipalities can be achieved by combining individual heating and district ... more Carbon neutrality in municipalities can be achieved by combining individual heating and district heating solutions involving the use of renewable energy sources. Each approach has advantages and disadvantages, but the best solution depends on the specific circumstances of each municipality. As an environmentally friendly and efficient energy use, a decentralised heat supply contributes to achieving energy conservation and emissions reduction goals. Decentralised energy use, such as solar collectors with thermal energy storage or biomass as a resource, reduces dependence on centralised heat generation and transmission. The appropriate infrastructure for connection to district heating networks has not yet been built. On the other hand, it is easier to make investments to construct proper infrastructure in the case of large-scale centralised heat supplies. Moreover, a centralised heat supply with renewable energy sources can provide more inhabitants with renewable heat energy. Within t...
ENVIRONMENT. TECHNOLOGIES. RESOURCES. Proceedings of the International Scientific and Practical Conference
Global trends in the world are currently representing a serious incentive to bring ‘green thinkin... more Global trends in the world are currently representing a serious incentive to bring ‘green thinking’ to life. This is the case of replacing synthetic materials derived from fossil resources with natural-origin, renewable resources. In the automotive industry and other segments of the manufacturing industry, increasing attention is being paid to the use of natural fibers in the manufacturing of composite materials. For example, flax and hemp fiber, as reinforcing material, is starting to widely replace carbon fiber. It is not just an ecological benefit, but also an important product protecting human health, since the amount of emissions that pollute the environment is minimized. Consequently, that lead to reduced intake by human being of harmful substances that would affect its health status. Existing composite materials used in motor vehicles, produced from carbon fibers, are creating very sharp fracture areas in the event of accidents causing human injury, while materials from natur...
Due to the rising demand for food and feed, agricultural waste increases, while plastic pollution... more Due to the rising demand for food and feed, agricultural waste increases, while plastic pollution increases due to hostile human activities. The sustainable way to utilize agricultural waste and promote the bioeconomy concept is to produce an alternative product of plastic, i.e., ‘bioplastic’. This paper used different keywords to perform the bibliometric analysis of the scientific publication related to bioplastic, agricultural waste, and sustainability. Remarkably, results show the increasing research interest in bioplastic with the key developing trends in sustainable bioplastic production, agriculture waste management, biopolymer, and biological processes. The identified developing trends can be used for further research to create a sustainable agricultural sector and produce higher added-value products. Moreover, this study discovered that the agro-biopolymer area needs more focus on sustainable development considering the economic, social, and environmental dimensions.
2020 IEEE 61th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)
The aim of the circular economy is to maximize the value of a product during its use, using secon... more The aim of the circular economy is to maximize the value of a product during its use, using secondary raw materials to create new products. This research focus on the possibilities of using waste as an energy resource - both the aspects of waste recovery, from the point of view of reducing the amount of landfilled waste, and the extraction and further efficient use of landfill gas. In this case the TOPSIS analysis method was used, five alternatives were selected - waste as an energy resource, which was evaluated based on four criteria: technological, economic, social, as well as environmental and climate aspects. The results of ranking energy recovery methods from waste using the TOPSIS method clearly show that the most optimal of the selected alternatives is the use of biodegradable (organic) waste for biogas production. This opens up opportunities for biofuels to be applied in road transport.
This analysis aims to identify the potential of bio-diplomacy focused on forestry resources in La... more This analysis aims to identify the potential of bio-diplomacy focused on forestry resources in Latvia. As the resources are scarce, small states must calibrate their foreign policy to gain a global vision by offering strategic products or services. In order to identify this potential, there are employed the Analytic Hierarchy Process (AHP) and the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) analytical methods. The results indicate that economy, climate and environmental and social factors are the most important elements to be considered. The most important driving forces for using forestry resources for bio-diplomacy are demand, volume and renewal.
2019 IEEE 60th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON), 2019
The research focuses on evaluating the impact of large manufacturing enterprises both on country&... more The research focuses on evaluating the impact of large manufacturing enterprises both on country's economy and on environment from the perspective of energy intensity. The case study is based on the situation in Latvia. The research uses the Kaya identity to show the situation that is necessary to obtain in order to achieve the carbon emissions goals of the European Union. The research also provides an analysis on coincidences between Latvia's GDP, energy intensity and carbon intensity, as well as studies the input of the largest industries in Latvia on the country's energy intensity and provides suggestions for improving the manufacturing industry from the perspective of energy savings.
Within the framework of the study a case study is performed, the data provided by a Latvian texti... more Within the framework of the study a case study is performed, the data provided by a Latvian textile production company on their electricity and natural gas consumption, as well as production volumes over a three-year period have been analysed. The specific indicators of electricity, natural gas and CO2 emissions have been calculated and the obtained results are shown in graphs. The correlation of specific indicators with production volumes was analysed by correlation coefficient and linear regression methods. An analysis of statistical data for the calculated specific indicators over a three-year period has been performed. The obtained results show high seasonality of natural gas consumption and close connection between electricity consumption and production volumes.
During the experimental research, an algorithm was developed as a guide for the introduction of s... more During the experimental research, an algorithm was developed as a guide for the introduction of solar panels (PV) in centralized heat supply (CHS) companies and a SWOT analysis of the developed algorithm action blocks was performed. SWOT analysis was carried out for a project implemented in practise and, as a result of which the centralized heat supply system uses solar power with a total capacity of 30 kW. We found that in Latvia, the areas that are suitable for solar panels are several times higher than those required by the systems. Main tasks of the work: to analyse and study available literature and information on solar PV integration into CHS; analyse available solar PV power generation equipment and technologies; develop a roadmap for easy and understandable deployment of solar panels in the company.
Solar technologies are flexible and can be used for both centralized and decentralized energy pro... more Solar technologies are flexible and can be used for both centralized and decentralized energy production. The main aim of this article is to compare different solar technologies and configurations for integration into the DH system. The multi-criteria analyses method is used to rank different alternatives based on several criterions. The evaluation of criterions has been based on previous studies conducted. The multi-criteria analyses allow to compare different solar system alternatives that cannot be compared directly due to differences in their scale, type of energy produced and consumed, investment levels, etc. For the particular DH system researched, the most desirable solution is the PVT panel integration with an area of 1000 m2 which is aligned with the actual DH company’s power consumption. However, the results are strongly impacted by the assumed investment levels, efficiency of the technologies and other assumptions that could be further analysed by the help of sensitivity ...
One of the main pollution types is air pollution, which has a significant impact on the surroundi... more One of the main pollution types is air pollution, which has a significant impact on the surrounding environment and on living beings. Major source of air pollution is combustion processes. There are many flue gas treatment technologies around the world. In this paper a new, innovative flue gas treatment technology – fog unit – is introduced. The goal of the fog unit is to treat flue gases that are emitted from households. In the European Union, including Latvia, at the beginning of 2020, a directive will come into effect that will set limits for emissions and the effectiveness for incinerators in households. The main focus of this study was to determine the most optimal operating mode for the fog unit by changing different operating parameters: sprayed water temperature, sprayed water flowrate and types of nozzles (drop diameters). Results show that the most optimal operating mode in terms of flue gas treatment efficiency and recovered energy is at water temperature: 20 °C, sprayed ...
Aquaculture is currently the fastest growing food-producing sector in the world. The growth of th... more Aquaculture is currently the fastest growing food-producing sector in the world. The growth of this industry has been rapid for the last 25 years, however, aquaculture still relies heavily on feed input from wild capture fisheries. Landings in wild capture fisheries have been stagnant for the last two decades; therefore, new alternatives for conventional fish meal and fish oil need to be found. In this review, various alternatives are described and their advantages and disadvantages are evaluated. Single cell oils (SCO) and single cell proteins (SCP) produced by microorganisms are recognized as the alternative with the most potential for replacing fish meal and fish oil in aquacultures. However, production costs of SCOs and SCPsare still higher than production costs of Omega-3 rich oils from other sources (wild capture, plant derived oils and genetically modified plants); therefore, currently used substrates need to be replaced with cheaper agriculture and industrial biomass residue...
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