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IntroductionAn increase in the trend of rapid industrialization has resulted in the mushrooming of industries in various sectors throughout the world. This study tries to document caries prevalence among thermal power station workers in South India. Materials and MethodsA pilot study was conducted among 53 thermal power station workers, and based on the same, the sample size was calculated. ResultsThe caries prevalence was 62.5% in thermal power station I workers and 61.5% in thermal power station II workers. The mean DMFT was 2.96 among thermal power station I workers and 2.87 among thermal power station II workers. ConclusionThe caries prevalence was 79.2% in the 35- to 44-year-old age group, according to the National Oral Health Survey and Fluoride Mapping.

In a power plant, the fuel choice directly impacts the efficiency, cost, and ecological impact of generating electricity. For power plants to produce electricity effectively and affordably to fulfill the needs of consumers in homes, companies, and communities, they need a fuel supply that is constant, dependable, and inexpensive. In this study, we used the concept of multi-criteria decision-making (MCDM) to deal with the various criteria of fuel alternatives. We used the EDAS method as an MCDM methodology to rank the fuel alternatives and select the best one. The EDAS method is employed with the interval-valued neutrosophic sets (IVNSs) to deal with the uncertainty information in the evaluation process. We compute the weights of the criteria of thermodynamic parameters. We used ten thermodynamic parameters such as temperature, mass, energy, etc. Then, the principal results show that temperature is the best criterion, and the work interaction is the worst criterion in all criteria. The EDAS method ranked twenty alternatives. The results show that alternative 20 are the best and alternative 14 is the worst of all alternatives. We employed the sensitivity analysis to show the rank of alternatives under ten cases. The results show the 20 alternative is the best in all cases. The results are stable. [ABSTRACT FROM AUTHOR]

The PAHs transformation in the soils of the coal mining enterprises impact zones and thermal power plants remains poorly studied. In turn, coal mining can be considered as a primary cycle in the production of electricity. One of the main sources of negative environmental impact is the coal mining industry located on the territory of the upland in the south of the East European Plain. The features of PAHs accumulation in the soils of fuel and energy enterprises have been studied on the example of mines impact zones with different service life and the current coal-fired power plant. It was established that, regardless of the period and intensity of the emission source, as well as its current status, the polycyclic aromatic hydrocarbons (PAHs) content in the soils of the impact zones was significantly higher than in the soils of the background territory. The content of low molecular and high molecular weight PAHs in the impact zones soils differed depending on the land use type, as well as the period and intensity of an industrial effect type. The pollutants content of in the soils of all considered impact zones significantly exceeded the background values and according to the low molecular weight PAHs content in the soils, they formed the following decreasing series: Mayskiy ≥ Ayutinsky > Novoshahtinsk > Power station > Background. According the high molecular weight PAHs content, the series changed to: Novoshahtinsk >Mayskiy ≥ Ayutinsky > Power station > Background. Soil pollution markers for enterprises of the fuel and energy complex were identified as pyrene and chrysene, which are part of coal, formed from the hydrocarbon sources. The influence of the power plant was accompanied by the benzo(g,h,i)perylene concentration increase.

The PAHs transformation in the soils of the coal mining enterprises impact zones and thermal power plants remains poorly studied. In turn, coal mining can be considered as a primary cycle in the production of electricity. One of the main sources of negative environmental impact is the coal mining industry located on the territory of the upland in the south of the East European Plain. The features of PAHs accumulation in the soils of fuel and energy enterprises have been studied on the example of mines impact zones with different service life and the current coal-fired power plant. It was established that, regardless of the period and intensity of the emission source, as well as its current status, the polycyclic aromatic hydrocarbons (PAHs) content in the soils of the impact zones was significantly higher than in the soils of the background territory. The content of low molecular and high molecular weight PAHs in the impact zones soils differed depending on the land use type, as well as the period and intensity of an industrial effect type. The pollutants content of in the soils of all considered impact zones significantly exceeded the background values and according to the low molecular weight PAHs content in the soils, they formed the following decreasing series: Mayskiy ≥ Ayutinsky > Novoshahtinsk > Power station > Background. According the high molecular weight PAHs content, the series changed to: Novoshahtinsk >Mayskiy ≥ Ayutinsky > Power station > Background. Soil pollution markers for enterprises of the fuel and energy complex were identified as pyrene and chrysene, which are part of coal, formed from the hydrocarbon sources. The influence of the power plant was accompanied by the benzo(g,h,i)perylene concentration increase. [ABSTRACT FROM AUTHOR]

In the present-day conditions, the issue of energy saving is becoming increasingly acute and permanently relevant. This situation is caused by rapid growth in prices for primary energy resources and by the need to reduce the share of natural gas in the incoming part of the energy balance of Belarus. According to available statistics, with the commissioning of the Belarusian NPP, the share of natural gas in the incoming part of the energy balance decreases from 97 to 59 %. In the economic complex, the share of this primary energy resource is projected at 70 %. The problem of energy saving is solved most rationally and with the least investment only by increasing the efficiency of natural gas use, especially due to the commissioning of the Belarusian NPP, the issue of preserving the possibility of using centralized heating facilities is acute. It is necessary to increase the thermodynamic efficiency of the cycles of steam turbine plants, both heating and condensing, which form the basis of the generation of the Belarusian power system, in order to restore the energy characteristics of the power system, which have somewhat decreased with the commissioning of the NPP. In the limit, the share of natural gas in the incoming part of the energy balance should be reduced to values not exceeding 50 %, in accordance with the requirements of energy security. The article considers examples of utilization of low-temperature secondary energy flows occurring at thermal power plants: the heat of the cooling processes of the generator, lubrication systems, as well as the heat of condensation of turbine exhaust steam and deeper cooling of flue gases. On the basis of this review, it is expected to identify promising areas of relevant research in relation to the energy system of Belarus.

Based on 10 years of environmental monitoring located around the emission zone of an electricity supplier, the main regularities have been studied for the content of heavy metals (HMs), such as Pb, Cd, Zn, Cu, Ni, Mn, and Cr, and 16 priority polycyclic aromatic hydrocarbons (PAHs) in the soils of agricultural landscapes and their accumulation in Triticum aestivum. It has been shown that one of the most significant factors for the pollutants accumulation in soils and plants was the prevailing wind direction on the territory and atmospheric transfer of the dust particles of the enterprise with adsorbed pollutants. As the content of pollutants in the soil increased, their accumulation in Triticum aestivum increased with each season to a level exceeding maximum permissible concentrations (MPC), especially for Pb, Cd, and benzo[a]pyrene (BaP). The unambiguous influx of pollutants from the soil into the roots and further into the aboveground organs of the plant was typical only for Mn, Cr, and BaP, and the accumulation of other studied pollutants can be explained by their foliar influx. It has been established that Triticum aestivum was a more tolerant plant with respect to heavy metals pollution than PAHs. [ABSTRACT FROM AUTHOR]

The present study aimed to evaluate the potential toxic heavy metal (PTHM) concentrations and associated ecological and health risk of nearby inhabitants (child and adult populations) of the Bokaro thermal power station (BTPS), Jharkhand, India. The fly ash containing PTHMs is released from the thermal power plant and contaminates the soil of the nearby agricultural area, roadside area and residential area. Furthermore, PTHMs cause ecological risk as well as carcinogenic health effects in adults. Inhabitants are exposed to PTHMs through exposure pathways (for instance, direct ingestion, dermal contact and air inhalation), and PTHMs were examined in this study by calculating the estimated daily intake (EDI). The contamination factor (Cf) of Cd exceeded the threshold value throughout the study area, whereas the Cf of Hg was observed higher only in roadside soil (RSS). The geoaccumulation index (Igeo) of Cd was higher in the top soil of agricultural soil (AS) (7.39) and RSS (9.38). The level of PTHMs was monitored slightly higher in the topsoil of RSS. The ecological risk index (Eri) was detected to be the highest in RSS (1628.9). The permissible limit of Cd (0.05 mg kg−1) and Pb (0.1 mg kg−1) for all sampled vegetables and grain crops was surpassed. The transfer factor (TF) of the studied vegetables and grain crops was in the order of Cd > Cr > Pb > Hg > As. The results of the present study concluded that the hazard quotient (HQ) values for all PTHMs analysed in soil throughout the study area were < 1, which indicates that the child population was within the safe limit. However, the adult population was at a high risk of non-carcinogenic health effects due to increased permissible limits of Cd, Pb and Cr in vegetables and grain crops whereas the target carcinogenic risk (TCR) of Pb and Cr was higher and indicated that there may be a health risk of cancer in adults. [ABSTRACT FROM AUTHOR]

Çevresel konuların haberleştirilme biçimleri; çevre farkındalığı oluşturmada ve çevre bilinci yaratmada önemli bir role sahiptir. Bu çalışmada çevre ve insan hayatı üzerinde ciddi sorunlara neden olan termik santrallerle ilgili haberler çevre gazeteciliği bağlamında incelenmiştir. Bu doğrultuda; Cumhuriyet, Hürriyet ve Sabah isimli gazeteler örneklem olarak seçilmiş ve bu gazetelerin internet sayfalarında 25.11.2020-28.02.2021 tarihleri arasında yayınlanan haberler analiz edilmiştir. Termik santrallerle ilgili haberlerin nasıl sunulduğu, haberler üzerinden nasıl bir gerçekliğin üretildiği ve bu doğrultuda belirginleşen söylem biçimlerini ortaya koymak amacıyla yapılan bu çalışmada haberler eleştirel söylem analizi çerçevesinde incelenmiştir. Çalışma verileri değerlendirildiğinde Cumhuriyet gazetesinin termik santrallerle ilgili çevre odaklı bir habercilik anlayışı içerisinde olduğu ve çevre haklarının gözetilmesinin yanı sıra politik ve ideolojik tavrının çevre haberciliğine yansıdığı söylenebilir. Hürriyet ve Sabah gazetelerinde ise termik santrallerin ülke ekonomisine katkısı olduğu yönünde bir söylem geliştirildiği ve ekonomi politik unsurların belirleyiciliğinin çevre ile ilgili haberlerin üretim sürecine yansıdığı görülmektedir.

The article examines the relationship between China’s exports to African countries and the implementation of energy projects by Chinese companies. The structure of Chinese exports to Africa and trends in the development of bilateral trade is analyzed. Key factors explaining the close correlation between exports and project implementation are: first, the significant volume of tied financing provided by Chinese banks for the construction of energy infrastructure in African countries, second, the need of these countries to purchase a lot of high-tech equipment in the absence of relevant industries on their territory. The dynamics of supplies of specialized equipment from China used for the construction of various types of power plants - hydroelectric power plants, thermal power plants, wind power plants and solar power plants - is considered in detail. The article provides examples of energy projects of Chinese companies in African countries, for which the supply of equipment is directly found in the imports of the respective countries from China. The tendency for Chinese companies to open production facilities in African countries, in particular cement plants and a photovoltaic modules plant, is noted. The author concludes that the African market remains extremely promising for the implementation of energy projects and the sale of relevant Chinese products despite some negative factors.

Based on 10 years of environmental monitoring located around the emission zone of an electricity supplier, the main regularities have been studied for the content of heavy metals (HMs), such as Pb, Cd, Zn, Cu, Ni, Mn, and Cr, and 16 priority polycyclic aromatic hydrocarbons (PAHs) in the soils of agricultural landscapes and their accumulation in Triticum aestivum. It has been shown that one of the most significant factors for the pollutants accumulation in soils and plants was the prevailing wind direction on the territory and atmospheric transfer of the dust particles of the enterprise with adsorbed pollutants. As the content of pollutants in the soil increased, their accumulation in Triticum aestivum increased with each season to a level exceeding maximum permissible concentrations (MPC), especially for Pb, Cd, and benzo[a]pyrene (BaP). The unambiguous influx of pollutants from the soil into the roots and further into the aboveground organs of the plant was typical only for Mn, Cr, and BaP, and the accumulation of other studied pollutants can be explained by their foliar influx. It has been established that Triticum aestivum was a more tolerant plant with respect to heavy metals pollution than PAHs.

THE PURPOSE. Conducting a comparative analysis of the problems of efficient power supply torural consumers. Offering solution stop roblems by using multi-fuelmicrothermal power plants based on the Stirlingengine for ruralareas. Justification and description of prospects for the use of multi-fuelmicro-thermal power plants based on the Stirlingengine for ruralareas. METHODS. Methods of computer simulation of thermodynamic processes of multi fuel micro-thermal power plants based on an engine based on an engine with external heat supply are used. A computer simulation method has been developed that allows constructing a PV diagram and processes of changes in the pressure and volume of the working fluid depending on the position of the working piston and the displacer. Mathematical methods of analysis and description of the thermodynamic cycle of an engine with external heat supply are used. RESULTS. Выполнен анализ достижений и уровня современных достижений в области микро электростанций. Установлено направление развития научных исследований по разработке двигателя с внешним подводом тепла. Приведены некоторые результаты исследований по эффективности работы двигателя с внешним подводом теплоты. CONCLUSIONS . Одним из решений проблемы эффективного электроснабжения сельских потребителей может быть внедрения микро тепловых электростанций. Их использование позволит снизить стоимость электроэнергии и обеспечить ее бесперебойную поставку. Основой микро тепловой электростанции является двигатель с внешним подводом теплоты, работающий по принципу Стирлинга.

Aiming at the characteristics of large inertia，time delay and many influencing factors of SO2 e-mission concentration in the desulfurization system data，a prediction model of SO2 emission concentration based on bidirectional gated recurrent unit neural network (biGRU) is proposed・ Taking the main components obtained from the analysis as the input variables and the SO2 emission concentration as the output variable, the SO2 emission concentration is predicted through the data training・ The comparison reveals that the biGRU model can obtain higher prediction accuracy・ Compared with RNN and LSTM, the symmetric mean absolute percentage error decreased respectively by 4・ 235% and 0・ 718%, and the root mean square error decreased respectively by 1・ 942 mg/Nm³ and 0・ 443 mg/Nm3, which indicates that the biG・ RU model has lower prediction error，better generalization ability and higher practical application value, and is conducive to protect the environmental protection and reduce emission. [ABSTRACT FROM AUTHOR]

Modern trends in technical reequipment of coal-fired thermal power stations (TPS) are analyzed by the example of the Verkhnetagil'skaya District Power Station (GRES), where obsolete coal-fired power units requiring replacement were in operation. This problem is specific for many Russian thermal power stations. Two alternatives of reequipment are considered: replacement of obsolete steam-turbine power units with a natural gas-fired combined cycle unit (CCU) and conversion of coal-fired power units into integrated gasification combined-cycle units (IGCCU) with gas turbines operating on purified synthesis gas. Technical reequipment of the considered TPS was performed by replacing the coal-fired steam-turbine power units of phase I–II with a 420 MW CCU. The CCU core was a 288 MW Siemens SGT5-4000F gas turbine. A CCU on its basis was modelled in the THERMOFLEX code. The calculated results demonstrated high power and environmental effectiveness in replacement of coal-fired power units at TPSs with natural gas-fired CCUs, thereby cutting down coal equivalent consumption by 727 000 t.c.e. (or 24%). For conversion of a TPS to an IGCCU, the fuel saving could be as great as 543 000 t.c.e./year (18%) under comparable conditions. In this case, the atmospheric emissions (of dust and SO2) could be decreased many times (by 99%) due to implementation of an effective gas treatment process in the gasification system. Due to the huge coal reserves in Russia, the conversion of coal-fired TPSs to modern technologies with coal gasification may be a promising alternative for many TPSs during their reconstruction. In addition, it will contribute to improving the country's energy security. In addition, this will improve the country's energy security. [ABSTRACT FROM AUTHOR]

Using numerical methods, the basic characteristics of heat and mass transfer processes in the furnace chamber of the BKZ-75 boiler of the Shakhtinskaya TPP (Kazakhstan) were studied during a forced partial stop of the supply of coal dust through the burners. Two modes of fuel supply were studied; a direct-flow method of supplying air mixtures, when two direct-flow burners are working and two are in emergency mode and vortex method of supplying air mixtures - two vortex burners with a swirl angle of the air mixture flow and their inclination the center of symmetry of the boiler by 30° and two are in emergency mode. The computational experiments allowed to obtain the distributions of the total velocity vector, temperature fields, concentration fields of CO, NO2 throughout the entire volume of the combustion chamber and conduct a comparative analysis for the two investigated emergency mode (direct-flow and vortex). Based on the results, it can be concluded that in the case of a forced partial stop of the supply of coal dust, the use of the vortex method of supplying air mixtures improves heat and mass transfer processes and allows minimizing emissions of harmful substances. [ABSTRACT FROM AUTHOR]

In this article, I examined how ash can be used as an asphalt coating, the purpose of this article is to preserve the ecological balance and reduce the formation of ash dumps. In the zones where ash dumps are formed, unfavorable ecological situations are manifested due to the large amount of dust formation, as well as the washing out of ash components by sewage, after which the components of the ash fall into the soil, because of this, the mineralization of the groundwater increases and the environment degrades. Using this material will solve the environmental problem through the use of fly ash, but also to reduce the volume of ash dumps, freeing the occupied land for economic needs, from dumps of ash and ash-slag mixture.In this paper, I found out that the use of ash as an asphalt covering will not only reduce the occupied land, but will increase the performance characteristics of the road surface. [ABSTRACT FROM AUTHOR]

The regulations on stack designs at thermal power stations (TPS) has been analyzed. It is demonstrated that the applicable guidelines do not consider all the actual problems encountered in designing stacks for TPSs, such as optimization of the stack construction cost and its effective operation. The stack cost depends on its height and diameter, which, at a given connected capacity, are affected by the gas velocity in the stack channel. At present, the effective stack design procedures do not contain the notion of this economically feasible, cost-effective index, and the stack diameter is selected based on the engineering-and-cost estimation calculation procedures, which have not been approved as mandatory standards. These procedures are supported by the planning-and-distribution model of the country's economic development. The article announces a universal method developed by the authors for calculating the optimal flue gas velocity for any model of economic development irrespective of the trend in prices and expenditures for the production of goods and services. To calculate the optimal flue gas velocity, one should only input initial data valid at the present stage. The calculated results of the price factors' effect on the optimal flue gas velocity for single-flue and multiple-flue stacks are presented. Verification of the procedure against the initial data as of 1975 yields acceptable results. [ABSTRACT FROM AUTHOR]

The paper proposes the procedures for thermal and drinking water stations to operate under different conditions of low water levels. Thermal power stations are constructed near water sources to use water for the operation and cooling of steam turbines, as well as cooling only in other types of turbines; gas and combined. Drinking water stations are distributed along the Nile River from Aswan to Delta in different capacities of operation. Hydrodynamic (1-D) model is applied to estimate the Nile levels corresponding to the minimum flow. The water level is estimated for different cross-sections along the reach with an interval of 10 km. The cross-sections are extracted using a geographic information system from contour maps. An equation is created to specify the amount of required water for thermal power stations. Four alternative solutions are introduced for ensuring the operation of each station and recommendations are suggested for different solutions if required. [ABSTRACT FROM AUTHOR]

The relevance of the research is caused by necessity of making highly effective power-generating units on one of the directions, providing working out of a construction of the steam superheater and production engineering of steam overheat up to temperatures above 800 °С of the supercritical pressure before the immediate steam feeding into a turbine. The operation purpose: examination of the influence of enthalpic metering characteristics of a gas mixture (CH4+O2) close to stoichiometric composition, and feebly overheated steam of atmospheric pressure on the temperature of the reacting medium (products of combustion in the environment of steam), and also on qualitative and quantitative composition of a steam-gaseous intermixture over the range of metering characteristics of stable and resistant to burning. Research techniques. The authors used proved measurement techniques of all parameters of process in the automated mode of gathering and processing of the primary information: temperature, pressure, charge, composition of a gas condensed phase. The flowing method of concentration measuring of products in real time mode with a margin error ±5 % was also used. The relevance of the research is caused by necessity of making highly effective power-generating units on one of the directions, providing working out of a construction of the steam superheater and production engineering of steam overheat up to temperatures above 800 °С of the supercritical pressure before the immediate steam feeding into a turbine. The operation purpose: examination of the influence of enthalpic metering characteristics of a gas mixture (CH4+O2) close to stoichiometric composition, and feebly overheated steam of atmospheric pressure on the temperature of the reacting medium (products of combustion in the environment of steam), and also on qualitative and quantitative composition of a steam-gaseous intermixture over the range of metering characteristics of stable and resistant to burning. Research techniques. The authors used proved measurement techniques of all parameters of process in the automated mode of gathering and processing of the primary information: temperature, pressure, charge, composition of a gas condensed phase. The flowing method of concentration measuring of products in real time mode with a margin error ±5 % was also used.

The aims of this work are to analyze the changes in the world power industry during the time after the adoption of the United Nations Framework Convention on Climate Change of 1992 and to assess the extent to which the commitments of the Kyoto Protocol of 1997 have been met and evaluate the prospects of implementing the tasks of the Paris Agreement of 2015. Based on data on the production and consumption of various kinds of energy and the emissions of greenhouse gases, primarily carbon dioxide, in 1990–2017, changes in the structure of the global energy consumption, trends in electric power generation, and the influence of different factors on the carbon dioxide emissions in power-generating enterprises are investigated. It is shown that the power industry, which is the main source of anthropogenic greenhouse gases (GHGs), is the most inertial branch of the economy in terms of its contribution to the reduction in GHG emissions. Thus, in the first 2008–2012 commitment period of the Kyoto Protocol, GHG emissions in the state parties to the protocol decreased by 7.6% compared the base year, while other GHG sources reduced the emission by 18%. The corresponding figures for the following 2013–2017 commitment period were 10.6 and 17.1%, respectively. The maximum reduction in the carbon dioxide emissions in the power industry resulted from an increase in the global average efficiency of the thermal power stations from 32% in 1990 to 36% in 2017; as a consequence, the cumulative decrease in the CO2 emissions in the world during the 1990–2017 period was approximately 22 billion t. The increase in the electric power generation at HPPs and NPPs resulted in a reduction in GHG emissions by 16.7 and 10.7 billion t, respectively. The substitution of coal and fuel oil by gas at thermal power stations facilitated reducing the emissions by 5.2 billion t, while the use of renewable energy sources for generation of electric energy resulted in a reduction of 1.1 billion t. The contribution of the carbon capture and storage technologies amounting to only 0.2 billion t is not noticeable so far. [ABSTRACT FROM AUTHOR]