This study deals with the impact of Burshtyn thermal power station on the amount of manganese in soil, water and celandine tissue. The research of manganese amount and form in the system: water-plant is of great impo...This study deals with the impact of Burshtyn thermal power station on the amount of manganese in soil, water and celandine tissue. The research of manganese amount and form in the system: water-plant is of great importance due to active influence of thermal power station on the chemical structure of the polluted area. The changes in the amount and form of manganese in soil, water and plant are interrelated and depend on the season, the distance from the polluter and morph-functional plant structure, the cleaning system possibilities of the industrial enterprise and some meteorological factors.展开更多
Thermal power plants are generally constructed near to sea coast to meet their requirement of coolingwater. The warm water discharge from the thermal power plant is one of the major environmentalconcerns in view of th...Thermal power plants are generally constructed near to sea coast to meet their requirement of coolingwater. The warm water discharge from the thermal power plant is one of the major environmentalconcerns in view of the thermal pollution in the sea water. The temperature limit for the warm waterdischarge from the thermal power plant has to be monitored and controlled. Coastal Gujarat PowerLimited (CGPL) operates (24×7) at an “once-through system” based sea water circulation for powergeneration. The used sea water is then discharged into the sea through an outlet channel. As per environmental norms, the discharge water temperature needs to be maintained below the stipulated “delta”rise (+7 ℃) with respect to ambient sea surface temperature at the inlet. We demonstrate the applicability of thermal remote sensing data in understanding the seasonal and temporal variations of thetemperature difference between the discharge water and the ambient sea water. We used thermal banddata from Landsat-8 satellite imagery to map water surface temperature and create temperature profilesalong the intake and outflow channels (till the sea), to understand the variation of temperature andestimate the “DT” between intake point and various observation points along the outflow. This analysiswas carried out for all 11 months (except June) of the year 2018 to correlate temperature variations withseasonal changes. Tidal conditions during the time of data acquisition were also considered to accountfor the effect of tides on DT. The result shows that the average temperature rise between intake andoutflow are maintained at ~3 ℃ across all the months of 2018, with minor variations in the months ofJuly and August. Further, average temperature drop from outflow to cooling channel (before diaphragm)is seen to be ~2 ℃ across all the months with similar seasonal fluctuations.展开更多
To this day, only two types of solar power plants have been proposed and built: high temperature thermal solar one and photovoltaic one. It is here proposed a new type of solar thermal plant using glass-top flat surfa...To this day, only two types of solar power plants have been proposed and built: high temperature thermal solar one and photovoltaic one. It is here proposed a new type of solar thermal plant using glass-top flat surface solar collectors, so working at low temperature (i.e., below 100°C). This power plant is aimed at warm countries, i.e., the ones mainly located between -40° and 40° latitude, having available space along their coast. This land based plant, to install on the seashore, is technologically similar to the one used for OTEC (Ocean Thermal Energy Conversion). This plant, apart from supplying electricity with a much better thermodynamic efficiency than OTEC plants, has the main advantage of providing desalinated water for drinking and irrigation. This plant is designed to generate electricity (and desalinated water) night and day and all year round, by means of hot water storage, with just a variation of the power delivered depending on the season.展开更多
An analysis for a conceptual design of a thermal power plant (with a power capacity of 1 GW) is provided. This power plant can help in meeting the expected increase in the electric demand for Oman’s dominant power sy...An analysis for a conceptual design of a thermal power plant (with a power capacity of 1 GW) is provided. This power plant can help in meeting the expected increase in the electric demand for Oman’s dominant power system (2.4 GW between 2018 and 2025). A necessary fluid mass flow rate of 834.1 kg/s was predicted. The overall energy conversion efficiency (output useful electricity divided by input heat) was estimated to be 34.7%. The needed thermal energy is not restricted to a specific source, and solar heating is an option for supplying the needed heat. The power plant design is based on using a steam-turbine section, which may be composed of a single large steam turbine having a mechanical power output of 1115 MW;or composed of a group of smaller steam turbines. The analysis is based on applying energy balance equations under certain assumptions (such as neglecting changes in potential energy). The thermal analysis was aided by web-based tool for calculating needed properties of the working medium, which is water, at different stages in the power plant.展开更多
Nowadays for power generation, environment is a major consideration. The heart of power generation is power station. At present there are almost above 40(Both Government & Rental) power station in Bangladesh. Amon...Nowadays for power generation, environment is a major consideration. The heart of power generation is power station. At present there are almost above 40(Both Government & Rental) power station in Bangladesh. Among these 80% of power station is gas based. Rest of the 20% is coal, liquid and furnace oil based. Bangladesh has only one Hydraulic power station. These gas and coal based power stations are giving adverse effect in Bangladesh. The main emissions from coal combustion at thermal power plants are carbon dioxide (CO), nitrogen oxides (NO), sulfur oxides (SO), chlorofluorocarbons (CFCs), and air- borne inorganic particles such as fly ash, soot, and other trace gas species. Carbon dioxide, methane, and chlorofluorocarbons are greenhouse gases. These emissions are considered to be responsible for heating up the atmosphere, producing a harmful global environment. It is known to all that hydro power station is a clean source of energy, but it has also some ecological and environmental effect. Dhaka is one of the top polluted city in the world. So for power generation if the environmental effect is not considered then Bangladesh will be in great trouble. The purpose of this paper is to discuss the present and future possible environmental effect of power generation in Bangladesh.展开更多
With countries proposing the goal of carbon neutrality,the clean transformation of energy structure has become a hot and trendy issue internationally.Renewable energy generation will account for the main proportion,bu...With countries proposing the goal of carbon neutrality,the clean transformation of energy structure has become a hot and trendy issue internationally.Renewable energy generation will account for the main proportion,but it also leads to the problem of unstable electricity supply.At present,large-scale energy storage technology is not yet mature.Improving the flexibility of coal-fired power plants to suppress the instability of renewable energy generation is a feasible path.Thermal energy storage is a feasible technology to improve the flexibility of coal-fired power plants.This article provides a review of the research on the flexibility transformation of coal-fired power plants based on heat storage technology,mainly including medium to low-temperature heat storage based on hot water tanks and high-temperature heat storage based on molten salt.The current technical difficulties are summarized,and future development prospects are presented.The combination of the thermal energy storage system and coal-fired power generation system is the foundation,and the control of the inclined temperature layer and the selection and development of molten salt are key issues.The authors hope that the research in this article can provide a reference for the flexibility transformation research of coal-fired power plants,and promote the application of heat storage foundation in specific coal-fired power plant transformation projects.展开更多
The increase of water temperature, due to thermal discharges from two nuclear power stations, was one of the most significant environmental changes since 1982 in the Daya Bay, located in the north of the South China S...The increase of water temperature, due to thermal discharges from two nuclear power stations, was one of the most significant environmental changes since 1982 in the Daya Bay, located in the north of the South China Sea. This study investigates the long-term (1982-2012) environmental changes in Daya Bay in response to the increase of water temperature, via comprehensively interpreting and analyzing both satellite and in situ observations along with previous data. The results show that: 1) salinity, dissolved oxygen (DO), chemical oxygen demand (COD) and nutrients had been enhanced after the thermal discharges started in 1994;2) the concentration of Chl-a increased while the net-phytoplankton abundance decreased;3) diversity of the phytoplankton community had decreased;4) fishery production had declined;and 5) frequency of Harmful Algal Bloom occurrence had increased. Satellite images show clearly that a thermal plume from the power stations extended toward the interior of Daya Bay, and that surface temperature of the seawater increased as one approached the power stations. The analysis suggests that the thermal water discharged from the two power stations was a driver of the ecosystem’s change in Daya Bay. Several factors, including nutrients, salinity, DO, and COD, varied according to the increase of water temperature. These factors affected the water quality, Chl-a, and phytoplankton in the short term and impaired aquatic organisms and the whole ecosystem in the long term.展开更多
文摘This study deals with the impact of Burshtyn thermal power station on the amount of manganese in soil, water and celandine tissue. The research of manganese amount and form in the system: water-plant is of great importance due to active influence of thermal power station on the chemical structure of the polluted area. The changes in the amount and form of manganese in soil, water and plant are interrelated and depend on the season, the distance from the polluter and morph-functional plant structure, the cleaning system possibilities of the industrial enterprise and some meteorological factors.
文摘Thermal power plants are generally constructed near to sea coast to meet their requirement of coolingwater. The warm water discharge from the thermal power plant is one of the major environmentalconcerns in view of the thermal pollution in the sea water. The temperature limit for the warm waterdischarge from the thermal power plant has to be monitored and controlled. Coastal Gujarat PowerLimited (CGPL) operates (24×7) at an “once-through system” based sea water circulation for powergeneration. The used sea water is then discharged into the sea through an outlet channel. As per environmental norms, the discharge water temperature needs to be maintained below the stipulated “delta”rise (+7 ℃) with respect to ambient sea surface temperature at the inlet. We demonstrate the applicability of thermal remote sensing data in understanding the seasonal and temporal variations of thetemperature difference between the discharge water and the ambient sea water. We used thermal banddata from Landsat-8 satellite imagery to map water surface temperature and create temperature profilesalong the intake and outflow channels (till the sea), to understand the variation of temperature andestimate the “DT” between intake point and various observation points along the outflow. This analysiswas carried out for all 11 months (except June) of the year 2018 to correlate temperature variations withseasonal changes. Tidal conditions during the time of data acquisition were also considered to accountfor the effect of tides on DT. The result shows that the average temperature rise between intake andoutflow are maintained at ~3 ℃ across all the months of 2018, with minor variations in the months ofJuly and August. Further, average temperature drop from outflow to cooling channel (before diaphragm)is seen to be ~2 ℃ across all the months with similar seasonal fluctuations.
文摘To this day, only two types of solar power plants have been proposed and built: high temperature thermal solar one and photovoltaic one. It is here proposed a new type of solar thermal plant using glass-top flat surface solar collectors, so working at low temperature (i.e., below 100°C). This power plant is aimed at warm countries, i.e., the ones mainly located between -40° and 40° latitude, having available space along their coast. This land based plant, to install on the seashore, is technologically similar to the one used for OTEC (Ocean Thermal Energy Conversion). This plant, apart from supplying electricity with a much better thermodynamic efficiency than OTEC plants, has the main advantage of providing desalinated water for drinking and irrigation. This plant is designed to generate electricity (and desalinated water) night and day and all year round, by means of hot water storage, with just a variation of the power delivered depending on the season.
文摘An analysis for a conceptual design of a thermal power plant (with a power capacity of 1 GW) is provided. This power plant can help in meeting the expected increase in the electric demand for Oman’s dominant power system (2.4 GW between 2018 and 2025). A necessary fluid mass flow rate of 834.1 kg/s was predicted. The overall energy conversion efficiency (output useful electricity divided by input heat) was estimated to be 34.7%. The needed thermal energy is not restricted to a specific source, and solar heating is an option for supplying the needed heat. The power plant design is based on using a steam-turbine section, which may be composed of a single large steam turbine having a mechanical power output of 1115 MW;or composed of a group of smaller steam turbines. The analysis is based on applying energy balance equations under certain assumptions (such as neglecting changes in potential energy). The thermal analysis was aided by web-based tool for calculating needed properties of the working medium, which is water, at different stages in the power plant.
文摘Nowadays for power generation, environment is a major consideration. The heart of power generation is power station. At present there are almost above 40(Both Government & Rental) power station in Bangladesh. Among these 80% of power station is gas based. Rest of the 20% is coal, liquid and furnace oil based. Bangladesh has only one Hydraulic power station. These gas and coal based power stations are giving adverse effect in Bangladesh. The main emissions from coal combustion at thermal power plants are carbon dioxide (CO), nitrogen oxides (NO), sulfur oxides (SO), chlorofluorocarbons (CFCs), and air- borne inorganic particles such as fly ash, soot, and other trace gas species. Carbon dioxide, methane, and chlorofluorocarbons are greenhouse gases. These emissions are considered to be responsible for heating up the atmosphere, producing a harmful global environment. It is known to all that hydro power station is a clean source of energy, but it has also some ecological and environmental effect. Dhaka is one of the top polluted city in the world. So for power generation if the environmental effect is not considered then Bangladesh will be in great trouble. The purpose of this paper is to discuss the present and future possible environmental effect of power generation in Bangladesh.
基金funded by National Key R&D Program of China,grant number 2019YFB1505400 and 2022YFB2405205.
文摘With countries proposing the goal of carbon neutrality,the clean transformation of energy structure has become a hot and trendy issue internationally.Renewable energy generation will account for the main proportion,but it also leads to the problem of unstable electricity supply.At present,large-scale energy storage technology is not yet mature.Improving the flexibility of coal-fired power plants to suppress the instability of renewable energy generation is a feasible path.Thermal energy storage is a feasible technology to improve the flexibility of coal-fired power plants.This article provides a review of the research on the flexibility transformation of coal-fired power plants based on heat storage technology,mainly including medium to low-temperature heat storage based on hot water tanks and high-temperature heat storage based on molten salt.The current technical difficulties are summarized,and future development prospects are presented.The combination of the thermal energy storage system and coal-fired power generation system is the foundation,and the control of the inclined temperature layer and the selection and development of molten salt are key issues.The authors hope that the research in this article can provide a reference for the flexibility transformation research of coal-fired power plants,and promote the application of heat storage foundation in specific coal-fired power plant transformation projects.
文摘The increase of water temperature, due to thermal discharges from two nuclear power stations, was one of the most significant environmental changes since 1982 in the Daya Bay, located in the north of the South China Sea. This study investigates the long-term (1982-2012) environmental changes in Daya Bay in response to the increase of water temperature, via comprehensively interpreting and analyzing both satellite and in situ observations along with previous data. The results show that: 1) salinity, dissolved oxygen (DO), chemical oxygen demand (COD) and nutrients had been enhanced after the thermal discharges started in 1994;2) the concentration of Chl-a increased while the net-phytoplankton abundance decreased;3) diversity of the phytoplankton community had decreased;4) fishery production had declined;and 5) frequency of Harmful Algal Bloom occurrence had increased. Satellite images show clearly that a thermal plume from the power stations extended toward the interior of Daya Bay, and that surface temperature of the seawater increased as one approached the power stations. The analysis suggests that the thermal water discharged from the two power stations was a driver of the ecosystem’s change in Daya Bay. Several factors, including nutrients, salinity, DO, and COD, varied according to the increase of water temperature. These factors affected the water quality, Chl-a, and phytoplankton in the short term and impaired aquatic organisms and the whole ecosystem in the long term.