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The steam condenser is a crucial component in power plants, playing a vital role in influencing the overall performance of steam power plants. This paper delves into a detailed assessment of the thermal aspects and evaluation of steam surface condensers. To conduct this rigorous evaluation, we meticulously crafted a three-dimensional (3D) model of a multi-tube single-pass counter-flow heat exchanger using ANSYS Design-Modeller. Within this model, a multiphase mixture model was harnessed to replicate the condensation process that takes place within the condenser. After the model's development, a series of computational fluid dynamics (CFD) simulations were expertly executed utilizing ANSYS Fluent Workbench. The simulations encompassed diverse cooling water flow rates and steam inlet velocities. Notably, two sets of CFD simulations were carried out: the initial set featured a velocity inlet in the condenser, while the second set involved CFD simulations with a pressure steam inlet. The findings derived from these simulations unveiled a noteworthy correlation between the condensation rate within the shell and both the rate of circulating water flow and the operational pressure of the condenser. Additionally, it was discerned that the condensation rate could be further influenced by the specific geometry of the condenser. In sum, this study concludes that optimizing the geometrical configuration and baffle arrangements holds promise for increasing the condensation rate and overall performance of steam condensers employed within steam power plants. [ABSTRACT FROM AUTHOR]

Biomass residues from the aromatic and medicinal oil extraction industries were used as fuel to produce steam necessary for the extraction of essential oils (EO) by hydrodistillation from a plant around the Mediterranean, Daucus carota L. The results obtained in terms of yield and extraction time were compared to those obtained by the classical method of hydrodistillation (HD) using electric heating. Several advantages with hydrodistillation in the presence of biomass as an energy source (BEHD) have been observed: faster kinetics and higher efficiency with similar yields: 1.03% and an extraction time of 30 min against 180 min for classic hydrodistillation. The antimicrobial activity and the antioxidant activity of the EO extracted by HD and BEHD were evaluated. The results showed that the oil extracted by BEHD has a better antioxidant activity and it is much more active than that isolated by HD. [ABSTRACT FROM AUTHOR]

This article presents a method of designing an optimal Proportional-Integral-Derivative (PID) controller for Automatic Generation Control (AGC) of a two-area interconnected thermal system. In addition, an application of Salp Swarm Algirithm (SSA) in order to design PID controllers is proposed. A method inspired by salp foraging behavior. The journey of the Salp group in the sea, by random the population of the salp and separated into leader salp and follower salp. The leader moves towards the food source and the rest of the followers follow the salp positioned in front of themselves. The parameters of PID were achieved by trial and error methods by designers. As an interconneted thermal power system with a Governor Deadband (GDB) is nonlinear and dynamic system, the Integral Squared Error (ISE) criterion has been used as objective function to find optimum controller gain. In order to solve this problem, SSA is proposed to concurrently tune PID gains of the PID controllers to minimize frequency deviations and tie-line power deviations by simulation the interconnected thermal power system. Compare of tuning PID controller from each optimization technique SSA and PSO. Simulation results clearly show that the performance of the system after taking SLP into the interconnected thermal power system that tuning by SSA and PSO and the robustness of the optimal PID controllers are superior to the conventional PID controllers in terms of settling time (-10.46 % in area 1, +0.87 % in area 2 and +0.57 % in power tie-line), overshoot (-10.61 % in area 1 and -10.87 % in area 2) that obtain by (SSA) method less value than the value that obtain by (PSO) method and the power tie-line. Integral Absolute Error (IAE) (-0.38 %) that obtain by (SSA) few errors. Comparisons to the tuned with Particle Swarm Optimization (PSO) approaches is also included. [ABSTRACT FROM AUTHOR]

This paper presents an improved pelican optimization algorithm (IPOA) to solve the economic load dispatch problem. The vertical crossover operator in the crisscross optimization algorithm is integrated to expand the diversity of the population in the local search phase. The optimal individual is also introduced to enhance its ability to guide the whole population and add disturbance factors to enhance its ability to jump out of the local optimal. The dimensional variation strategy is adopted to improve the optimal individual and speed up the algorithm's convergence. The results of the IPOA showed that coal consumption was reduced by 0.0292%, 2.7273%, and 3.6739%, respectively, when tested on 10, 40, and 80-dimensional thermal power plant units compared to POA. The IPOA can significantly reduce the fuel cost of power plants. [ABSTRACT FROM AUTHOR]

Today, the world is turning to use renewable energy to solve the problems of fuel shortage and pollution due to CO2 emissions from the use of fossil fuels. In this study, parabolic trough solar collectors (PTC) with two types of heat transfer fluids HTF are used to investigate the performance of a retrofitted steam power plant using solar energy. A thermo-economic analysis was performed for a 10 MW simple steam power plant with different boiler pressure from 10 to 100 bar and located in the city of Basra in Iraq which receives high levels of solar radiation. Basra's weather conditions are used to simulate the solar-assisted regenerative system using a parabolic trough collector (PTC). According to the system analysis, it was found that increasing the boiler pressure reduces the area required for the PTC heater for constant power output. For 10 bar operating pressure the required PTC area is 64233,562 m² while for 100 bar operating pressure the required PTC area is 42907.59 m². Also, it was estimated that the Levelized Cost of Energy (LCOE) decreased with increasing operating pressure. The decrease in LCOE for PV1 heating fluid is 43.25% and the decrease in LCOE is 43.16% for the pressure range from 10 to 100 bar. [ABSTRACT FROM AUTHOR]

Pneumatic fly ash conveying systems in thermal power plants are often not able to transport ash as per their expected duty due to either variability of ash characteristics and/or inadequate system sizing resulting in generation loss and reduced ash utilization. This paper results from an ongoing investigation into the relationship between the physical characteristics of ash to some of the important design criteria, such as ash conveyability and flowability. Based on a comprehensive test program including the pneumatic conveying (in a pilot plant) and flow property testing of 23 ash samples obtained from five different power stations, predictions for conveyability and flowability have been made using bulk property characterization. Of all the different particle and bulk parameters investigated, the angle of repose has been found to be the most significant parameter linking conveyability and flowability. A newly developed design tool based on the angle of repose is expected to assist designers and operational engineers to predict the flow condition and appropriately size equipment/system with suitable operating parameters. [ABSTRACT FROM AUTHOR]

Nuclear power plant steam generator (SG) tubes contain nickel as the main alloying element and there is concern about their corrosion. We optimized models for calculating the high‐temperature and high‐pressure thermodynamic properties of common nuclear alloy elements. Subsequently, we calculated the E–pH diagrams for nickel in different concentrations of ammonia or acetate ion at temperatures ranging from 100°C to 260°C and a pressure of 4.7 MPa. This information is used to predict the corrosion behavior of nickel in the secondary circuit conditions of Canadian Deuterium Uranium (CANDU) SGs. Increasing the ammonia or acetate ion concentration resulted in the predominance of Ni(NH3)n2+ or Ni(Ac)n(2−n) at the expense of Ni2+ and NiO, indicating a higher risk of nickel corrosion. Calculations showed that under normal operating conditions with [NH3]tot = 5 × 10−5 and [CH3COO−]tot = 10−8 m at 260°C and 4.7 MPa, nickel will be passivated as NiO, preventing the rapid degradation of nickel‐based alloys. However, in the presence of a crevice that allows the acetate ion to concentrate, nickel would dissolve in the form of the Ni2+ ion, endangering safe operation of CANDU SGs. [ABSTRACT FROM AUTHOR]

The demand of Rare Earth Elements (REEs) has increased for the development of clean and green technologies. Conventional geological sources of REE are insufficient to overcome the high demand of REE; hence, the secondary resources are being actively explored. Coal ashes (CAs), a potentially hazardous material, is one of the best secondary sources containing high concentration of REE. The present study aims to explore the abundance of REE in coal and coal ash from different Thermal Power Stations (TPS). The mineralogy and surface morphology of all samples have been determined. The coals mostly consist of quartz and kaolinite, whereas CAs predominantly contain quartz and mullite. Both coal and CAs are dominated by LREE elements, followed by MREE and HREE. The outlook coefficient (Cout) is close to "1" and the critical percentage (Cp) is more than 30%. Coal ash from some of the TPS is identified as secondary source for REE. Fractionation study of REE from coal to CA is carried out to understand the feasibility of CA. A Pearson correlation has been plotted for individual REE elements with other parameters to understand the affinity of REE to different phases of CA. [ABSTRACT FROM AUTHOR]

The contents of 49 trace elements in sub-bituminous Pernik coals and their waste products from preparation and combustion processes were investigated. The studied coals have trace element contents higher than the respective Clarke values for brown coals and some of them may pose environmental concerns. The elements Li, Rb, Cs, Ba, Sc, Y, La, Ce, Nd, Sm, Eu, Er, Ga, Zr, Sn, V, Nb, Ta, W, F, Cu, Zn, In, Pb, Cr, Co, Ni, and Th in the feed coals have concentrations that exceed twice the Clarke values. Most element contents in bottom ash are enriched compared with those in feed coal. Some of the volatile elements are equal or significantly depleted including Sn, Mo, Sb, F, Bi, Cd, Ge, and Pb. Fly ash has higher contents of Ga, Zr, Hf, Sn, V, Nb, Mo, and F in comparison with bottom ash. Most elements have a significant positive correlation with ash yield, indicating their inorganic association. The mixed wastes (coal slurry, bottom ash, and fly ash) in the disposal pond are slightly depleted of most of the elements studied with the exclusion of Cl, Ba, and Br. The Pernik coals and their waste products are unpromising for the extraction of REY due to their low element contents. [ABSTRACT FROM AUTHOR]

Measurements of radon and thoron concentrations were taken at 70 locations in and around Gandhinagar Gujarat, India. The radon concentration varied between 175 and 14,807 Bq/m3, whereas, thoron varied between 28 and 15,033 Bq/m3. Maximum concentration of radon and thoron is observed in northern and eastern part of Gandhinagar due to fly ash content of the soil discharged from the Gandhinagar thermal power station. The annual dose rate due to inhalation varied between 0.0013 and 0.1337 mSv/year, below the ICRP recommendation. High radon concentrations are also observed in dumping areas and geological structures with high seismic risk. [ABSTRACT FROM AUTHOR]

Emissions from thermal power plants have always been the central consideration for environmental protection. Existing optical sensors in thermal power plants usually measure the total mass concentration of the particulate matter (PM) by a single-wavelength laser, bearing intrinsic errors owing to the variation in particle size distribution (PSD). However, the total mass concentration alone cannot characterize all the harmful effects of the air pollution caused by the power plant. Therefore, it is necessary to measure the mass concentration and PSD simultaneously, based on which we can obtain multi-particle-size channel mass concentration. To achieve this, we designed an optical sensor based on the three-wavelength technique and tested its performance in a practical environment. Results showed that the prototype cannot only correctly measure the mass concentration of the emitted PM but also determine the mean diameter and standard deviation of the PSDs. Hence, the mass concentrations of PM10, PM2.5, and PM1 are calculated, and the air pollutants emission by a thermal power plant can be estimated comprehensively. [ABSTRACT FROM AUTHOR]

The quality of the intermediate point temperature control of a supercritical unit is directly related to the quality of the coal–water ratio and main steam temperature control of the supercritical unit, which is also related to the economy and safety of the unit. In order to improve the accuracy of short-term predictions of the intermediate point temperature, a short-term prediction model of the intermediate point temperature based on the EEMD (Ensemble Empirical Mode Decomposition)-LSTM (Long Short-Term Memory) model is proposed. This model uses the data of a 600 MW thermal power station in 2022 as a sample. The EEMD method is used to decompose the historical data into IMF components and residual components, and the correlation between each component and the original data is calculated. The relevant components are sent to the LSTM neural network, and all the sub-components are superimposed to obtain the final intermediate point temperature prediction results. At the same time, the BP and LSTM models are built to compare the errors with the proposed model. The results show that the single model will produce large errors when predicting the factors of large data fluctuations. The EEMD–LSTM coupling model can fully extract the detailed features and the prediction effect is obvious. The prediction accuracy of the EEMD–LSTM prediction model built in this paper is significantly better than that of the other two models. It has certain application value in the research field of intermediate point temperature prediction and can meet the requirements of short-term predictions of the intermediate point temperature. [ABSTRACT FROM AUTHOR]

Driven by upstream high-pressure steam, liquid slugs in nuclear power plant pipelines impact the end orifice at high speed, leading to bursting pipelines and threatening the plant's safety. This research aimed to accurately and efficiently assess the dynamic behavior of an isolated slug driven by pressurized air in a voided line with an end orifice. An improved one-dimensional (1D) model for the slug motion and impact was established. The dynamic variation of the pressure at both the slug's tail and front, the variation of the slug length, and the frictional resistance coefficient in the model was obtained by three-dimensional (3D) computational fluid dynamics (CFD). Based on 27 cases with different pipeline diameters and tank pressures, it was observed that the driving air pressure had a quadratic relationship and that the slug length had a constant rate of decrease vs the slug tail displacement. Finally, the decrease in the driving air pressure behind the slug, the increase in the air pressure ahead of the slug, the holdup coefficient, and the friction factor obtained from the 3D CFD results were interpreted in the 1D model, and the velocity histories of the liquid slug were found to be in excellent agreement with the 3D CFD solutions. [ABSTRACT FROM AUTHOR]

The primary goal of this research paper is to inculcate AI approaches in thermal power plants to raise automation at power plants by expanding the integrated control idea to thermal power plants and implementing it using AI approaches. The recommended control method will be analysed and contrasted with established strategies. The crucial condition will be evaluated even though the suggested type of control system doesn't come up with an effective result. The development of the conceptual model is predicated on the state of power generation technologies. There will be no suggestion to use newer or different technology, such as fluidised bed combustion, sliding pressure units or ultra-supercritical plants, in the process of producing electricity. This study specifically focuses on the operational features of the control system instead of the hardware technologies. [ABSTRACT FROM AUTHOR]

Rejection of unknown disturbances and uncertainties in high‐order nonlinear systems with large delays is an important control problem. Active disturbance rejection control (ADRC) solves disturbances and uncertainties in a simple and effective way. In engineering, low‐order ADRC is often used to control high‐order large‐delay systems because of its ease of implementation and simplicity of operation. However, this leads to the problem that the low‐order ADRC has a limited ability to configure the high‐order nonlinear systems. The desired dynamics and the closed‐loop dynamics are almost always very biased. For a class of high‐order nonlinear systems with delay, a bias feedback compensation (BFC) approach to ADRC is suggested. This strategy works by adding a feedback loop based on the desired dynamics over the ADRC loop. The BFC strategy can improve the poor performance of low‐order ADRC for higher‐order nonlinear systems. In addition, a synthesis parameter tuning procedure of BFC‐ADRC is proposed in this article. Then, the stability problem is analyzed in this article. Finally, high‐fidelity simulation studies on a 1000 MW power plant for superheater steam temperature control and experiments on three interacting water tanks for level control are performed to verify the tracking, disturbance rejection, and robustness of the control strategy. Both simulation and experiments show that the method is highly robust and significantly improves both disturbance rejection and tracking performance. [ABSTRACT FROM AUTHOR]

Summary: Demand for Florida organic strawberries has significantly increased in recent years, yet this industry is threatened by pests and pathogens that often come with transplants from out-of-state nurseries. Plant steaming has been explored as an alternative to reduce those threats in transplants. This study evaluated the yield performance of seven strawberry cultivars and their impact on nematode densities and plant vigour after steaming was applied to transplants imported from California during two growing seasons (2020-2021 and 2021-2022). The cultivars used were 'Sensation® Florida127', 'Florida Brilliance', 'Florida Radiance', 'Winterstar™ FL 05-107', 'Florida Elyana', 'Strawberry Festival' and 'Florida Beauty'. Plant steaming reduced plant vigour only 4 weeks after transplanting. Nevertheless, no negative effect was observed in total fruit yield. Differences among cultivars were observed for plant vigour, total fruit yield and abundance of root-knot nematodes. The plant vigour of each cultivar depended on the time of the year, which varied significantly throughout the season. Cultivars 'Sensation® Florida127' and 'Florida Radiance' attained the highest total yield in both seasons. There was an effect of the cropping system in the nematode community, which increased the bacterivores but drastically reduced omnivores and ring nematodes over time. No effect of cultivar was observed in plant-parasitic nematode populations. The cultivar 'Winterstar™ FL 05-107' was an exception since Meloidogyne javanica population densities were significantly higher in 'Winterstar™ FL 05-107's experimental plots. Overall, transplant steaming shows the potential to be a component of an integrated pest and disease management programme for the success of sustainable and profitable yields [ABSTRACT FROM AUTHOR]

Heat and electricity generation are major sources of air pollution in many large cities worldwide. In Siberian cities, the heat supply significantly contributes to air pollution, as coal remains the primary energy fuel in most of Asian Russia. Krasnoyarsk, the second-largest city in the macro-region by population, serves as a clear example of urban air pollution. In recent years, public authorities have implemented several measures to reduce pollutant emissions. These measures include modernizing thermal power stations, replacing inefficient small boiler houses, and converting residential heating to more environmentally friendly types of fuel. However, our analysis shows that these policies have not yet resulted in a significant transition away from using coal for heating. One of the primary reasons is that alternative fuels are unable to compete with coal in terms of price. The proposal suggests transitioning private households to pellet heating. Our goal is to evaluate the potential environmental and economic impacts of this measure. We estimate the necessary subsidy size for the successful implementation of both initiatives. In conclusion, converting households from coal to pellet heating can reduce the emissions of nitrogen oxides, carbon monoxide, sulfur oxides, and suspended particles by 0.2%, 8.5%, 4.4%, and 2.7%, respectively, of the total pollutant emissions in Krasnoyarsk. Furthermore, this conversion can provide economic benefits by supporting local pellet producers who heavily rely on export markets. If practically implemented, the proposed approach could solve one of the most significant development issues of one of the largest Russian cities within a few years, with only 2.5% of the annual city budget expenditure. [ABSTRACT FROM AUTHOR]

The study deals with the possibilities of using alternative types of fuels to produce electricity. Power Plant Vojany (PPV) is a thermal power plant (TPP) in eastern Slovakia, which is part of the company Slovenské elektrárne, a. s. (SE). PPV primarily used black coal to produce electricity, which had to be imported from abroad (the Russian Federation). This activity has become inefficient both economically and environmentally, due to the high price of CO2 permits and the high emission factor of this type of fuel. PPV decided to co-combust biomass and refuse-derived fuel (RDF), which resulted in much better economic conditions due to their price, economic efficiency, and partly closed CO2 cycle. The aim of the paper is to explore the possibilities related to the production of energy in the cleanest possible way and with the least possible damage to the environment in coal thermal power plants using the example of operating Power Plant Vojany located in eastern part of Slovakia and to inspire each other for the modern transformation. For the purposes of hypothesis verification, analytical methods focused on overview studies of average fuel prices, comparisons, and the balance of fuels in connection with eliminated CO2 emissions, as well as municipal waste (MW) management in the EU and V4 countries, were used. The authors also focused on the energy recovery and combustion of MW and tracking the achieved CO2 savings in connection with the development of fuel sources in PPV. The results point to the fact that PPV is one of the power plants that could use biomass and RDF as fuel, which confirms the economic advantages of this procedure. The results confirm that the potential of RDF production in Slovakia is sufficient to ensure the operation of PPV at planned, even higher volumes of electricity production. The transformation to cleaner operation of coal thermal power plants represents a significant contribution of this study. [ABSTRACT FROM AUTHOR]

The work is devoted to the development of a thermal scheme for the conversion of a cogeneration power plant to threegeneration with the production of hydrogen as a new product. The purpose of the work is to assess the possibility and potential of hydrogen production from MSW at the existing thermal power plants of St. Petersburg. To achieve this goal, it is necessary to develop a methodology for selecting the site of an existing thermal power plant in order to integrate a hydrogen production complex by the MSW gasification method, as well as a methodology for estimating the amount of hydrogen that can potentially be obtained from a given amount of MSW. The research methods include simulation of the thermal circuit of a steam power plant in the United Cycle program. The paper proposes an algorithm for selecting the site of an operating thermal power plant for the integration of a complex for the production of hydrogen by the method of MSW gasification. The algorithm can be applied to any subjects of the Russian Federation, and its relevance is confirmed by strategic documents. Potential locations for the new TPP are being considered in the territories of TPP-21 and TPP-22, which have the necessary resources and good infrastructure. As a result of the study, the site of TPP-22 was selected as the most suitable for the placement of new facilities. A new thermal scheme of a threegeneration power plant has been developed, including a hydrogen generation unit by the MSW gasification method. This allows the production of hydrogen in parallel with the production of electricity and heat. The efficiency evaluation criterion is the fuel heat utilization factor (FHUF). Regardless of the hydrogen content in the generated synthesis gas, the integration of the synthesis gas cooler into the thermal circuit of the TPP leads to an increase in the FHUF and an additional energy effect. This scheme increases the efficiency of existing TPP plants, regardless of the morphological composition of municipal solid waste. [ABSTRACT FROM AUTHOR]

The Nationally Determined Contribution (NDC) of Indonesia in the Paris Agreement targeted emission reductions of 29% on its own and 41% with international cooperation in 2030, followed by Net Zero Emissions (NZE) in 2060. To achieve NZE, Indonesia enacted a carbon tax policy on April 1, 2022. The 2022–2024 carbon tax is limited to Steam Power Plants and will be imposed on other sectors by 2030. This research examines the ratio legis of carbon cost policies in Indonesia and compares the core of carbon tax policies in Indonesia with Sweden and Finland. Indonesia is starting to implement a Carbon Pricing policy under the 'Cap-and-Tax' scheme. The Cap scheme will be a means to force changes in the business culture in Indonesia, so the companies will pay attention to and reduce the carbon emission produced to avoid paying penalties for carbon exceeding the limits. Meanwhile, the Carbon Tax will provide economic resources to Indonesia to develop environmentally friendly technologies, fund research on renewable energy, and provide incentives for environmentally friendly businesses during the transition process to a carbon culture in Indonesia. Referring to the results of the comparison of carbon pricing policies in Finland and Sweden, Indonesia can gradually increase the cost of carbon taxes starting from Rp30,000/US$2 per ton CO2 equivalent to US$10 per ton CO2 equivalent. Meanwhile, for the imposition of high carbon tax rates, such as in Finland (US$73.02 per ton CO2 equivalent) and Sweden (US$137 per ton CO2 equivalent), Indonesia must carry out tax reforms, so the applied carbon tax is able to reduce carbon emissions without causing adverse impacts for the Indonesian economy. [ABSTRACT FROM AUTHOR]

Repowering of old steam power plants is a viable solution to increase power and improve efficiency. This study investigates the feasibility of feed water heating repowering for the Neka steam power plant by considering the influences of steam mass flow rate on the condenser performance and the heat rate of the new cycle. Energy and exergy analyses were conducted using the first and second laws of thermodynamics and heat transfer relations in each scheme. The effect of increasing the steam mass flow rate on the performance of the condenser and the cycle was also investigated. The repowered cycle was simulated using Thermoflow software, and the results were validated with small errors. The results showed that replacing low and high-pressure heaters with new heat exchangers increased the power of the steam unit and the repowered cycle, energy, and exergy efficiencies by 15.7%, 49.3%, 5.93%, and 2.17%, respectively. Although the condenser pressure increased by 19 millibars, leading to a 0.63% increase in the heat rate, the total heat rate of the repowered cycle improved by 4.62%. Overall, the findings demonstrate that feed water heating repowering can be an effective strategy to increase the efficiency and power of conventional steam power plants. [ABSTRACT FROM AUTHOR]

This research delves into a comprehensive financial analysis and optimization of a tri-generation plant that integrates power generation, cooling capacity, and hydrogen production. The plant design encompasses an organic flash cycle, a two-phase ejector, and methanol steam reforming. Our investigation extends beyond thermodynamic evaluations, encompassing a thorough assessment of economic factors including energy economics, exergy-based financial metrics, and sustainability considerations. Moreover, we calculate critical financial indicators such as payback period and levelized costs to determine the economic feasibility of the tri-generation system. The study showcases the tri-generation system's ability to yield 32.58 kW of power, 246.5 kW of cooling capacity, and 12.56 kg/h of hydrogen in the base case configuration. Optimal energetic and exergetic efficiencies, along with a calculated payback period of 3.92 years, underscore the financial viability of the system. Through meticulous parametric studies, we uncover the intricate interplay between methanol molar ratios, reactor temperatures, and overall economic performance. This comprehensive financial profiling, when disclosed, could enhance regulatory oversight and shape financial supervision policies within the energy sector. [Display omitted] • Proposal of an innovative tri-generation plant powered by a methanol steam reforming cycle. • Simultaneous production of hydrogen, power, and cooling to enhance the efficiency of the base cycle. • Application of environmental and economic studies to evaluate system performance. • Introduction of bi-evaporator cooling and power cycle for the first time to recover heat in such a system. • Enhancement of economic and environmental indicators through bi-objective optimization. [ABSTRACT FROM AUTHOR]

In order to explore potential value of explosively growing data in thermal power unit, this paper proposes a big data mining method based on Hadoop-based Spark cluster-computing framework and algorithms. Firstly, positive and negative balance methods are used to accurately obtain actual net coal consumption, and maximum information coefficient method is used to select all parameters related to optimization objectives. Then, Spark-based Mini-Batch K-means algorithm and Elbow method are constructed to divide whole operating modes. After that, all data are discretized and mapped to corresponding intervals by using Spark-based Elbow method and Mini-Batch K-means algorithm. Finally, Spark-based parallel FP-growth algorithm is used to deeply mine the potential relationships and laws. To verify the proposed method, a 350-MW thermal power unit is taken as a study case. The important conclusions are as follows: (1) the proposed Spark-based Mini-Batch K-means algorithm reduces the calculation time by 57.11% compared with Mini-Batch K-means algorithm, and 85.61% calculation time compared with K-means algorithm. The proposed Spark-based FP-growth algorithm reduces computational time by 32.8% compared with FP-growth algorithm. (2) Strong association rules of whole operating modes are mined, and operating optimization guidance schemes for important parameters are obtained. Take operating mode 1 as an example: if the optimal result can be reasonably applied, it can save 2.942 g coal per kilowatt hour. (3) Besides, we have found out some other potential relationships among parameters, which have important reference value for on-site operators to analyze economy of the thermal power unit. [ABSTRACT FROM AUTHOR]

A steam-gas power plant (SGPP) combines a gas power plant (GPP) and a steam power plant by using the exhaust gas from the GPP to produce steam in the heat steam recovery generator (HRSG). The SGPP, which has a 200 ton/h HRSG capacity, experienced cracks, ruptures, and fatigue at the connection of the low-pressure evaporator pipe. Fatigue is a common failure mechanism in mechanical components due to thermal stress. However, the exact cause of the failure was unknown; therefore, a root cause analysis was conducted. Analysis included the thickness, metallography, chemical composition, tensile testing, thermography, defect testing, and hardness testing. The research showed thermal stresses were the cause of the low-pressure evaporator HRSG pipe failure. In addition, inspection results revealed a decrease in tensile strength, material hardness, and thermal expansion that exceeded the allowed limit. [ABSTRACT FROM AUTHOR]

A wide range of industrial processes (i.e., evaporation and condensation in desalination process, steam power plant, solar plant, etc.) involve heat transfer among the fluids. During the process of evaporative and cooling heat transfer, undesirable materials from the fluids accumulate on the surfaces, which critically reduces the performance of heat exchangers and creates one of the biggest challenges in energy transfer. Though the various studies on prediction and removal of fouling was conducted by numerous scientists, this problem is still unresolved in industrial process and is responsible for huge environmental damage and economic losses. This investigation provides a comprehensive overview of crystallization fouling in heat exchangers. Various factors affecting the deposition of crystallization foulaning such as fluid temperature, flow velocity, surface material and roughness, concentration and boiling are systematically reviewed. Accuracy and uncertainty of different equipment and experimental studies are discussed. In addition, fouling modelling is comprehensively discussed from earlier fundamental model to recent computational fluid dynamic and artificial neural networks model. Furthermore, mitigation of fouling with off-line and online approaches are chronologically discussed. Finally, an overview from environmental and economic prospective of fouling in heat exchangers are discussed. The future directions for crystallization fouling in heat exchangers are emphasized, which will support the researchers and industries to retard fouling and achieve economic benefits. [ABSTRACT FROM AUTHOR]

Facilities in power plants and thermal power plants must operate at high efficiency. Their efficiency largely depends on the quality of water as a cooling medium. Water is the most commonly used cooling medium in processes because it is generally available and has a large thermal capacity. The use of water results in a variety of consequences. The different compositions of water can cause scale deposits and contribute to the corrosion of system components. The exacerbation of the problem depends on the composition of the water and the operating conditions of the system. The lack of a low-cost and quick way to remove accumulated deposits that is also safe due to the chemicals used means that cleaning the system of deposits is not widely undertaken, especially in cases of small thermal power plants. Therefore, chemical cleaning is an extremely important part of plant operation. Due to the often-individual characteristics of each installation and the different sources of water as a refrigerant, it is important to know the different methods of descaling an installation. This article provides an overview of methods for descaling installations. Each of them has its own specific properties, allowing an individual approach to boiler scale removal. [ABSTRACT FROM AUTHOR]

Wastewaters from power plants is a major concern for environmental protection. After the water is used in thermal power plant, the heated effluent is again discharged in the same water body from where it is taken. This not only disturbs the aquatic life but also affects the balance of the ecosystem. This paper presents the background of the thermal pollution, modelling approach and analysis methods for prediction of thermal pollution. A 2-D model of Sava River is discussed. The thermal power plant Nikola Tesla B was considered. Analysis of thermal discharge into the Sava River for the twelve-year period has been carried out. It was done a comparative analysis of the results obtained using mathematical (Electricity of France - EDF) method and numerical analysis using the CFD software package ANSYS FLUENT. A comparison of these two methods was made in order to show that it is possible to predict thermal pollution precisely and that it is possible to apply these methods in the design of industrial plants and not only in large thermal power plants. Finally, the results showed the matching of the obtained values at greater distances from the water outlet of the thermal power plant. [ABSTRACT FROM AUTHOR]

The mechanical characteristics and structural features of the heat-resistant 12Kh1MF steel after long-term operation in a bend of the TPP (thermal power plants) steam pipelines were analyzed. The change in the technical state of the metal of different zones of the bend and the anisotropy of properties across the pipe wall thickness were established. It was found that in the stretched zone of the bend near the outer surface of the pipe the steel degraded more intense than in other zones, which was due to the most favorable operating conditions for creep. [ABSTRACT FROM AUTHOR]

Due to the increasing demand for electrical energy, efforts to increase the thermal efficiency of the steam and gas power plants have led to extensive reform in these cycles. One of these common reforms is employing a conventional combined gas‐steam cycle. In combined cycle power plants that are built to produce power, a significant portion of the input energy is lost. In this research to achieve the thermodynamic properties of a combined cycle power plant after modeling the cycle and determining the cycle potential independent variables, multiobjective optimization by imposing restrictions on cost functions and changing them concerning exergy efficiency has been analyzed. The results show that increasing the parameters of superheated temperature, pinch point temperature difference, pump exhaust pressure, and condenser inlet flow rate improves the system performance and increases exergy efficiency. It is shown by two‐objective optimization that when costs are increased up to 40%, exergy efficiency is increased, and when an increase is more than 40% repeated results would be obtained. Applying costs lower than 5% is not considered according to software limitations. Also, the results show that it is possible to increase exergy efficiency up to 79.7% with a 40% investment cost. [ABSTRACT FROM AUTHOR]

To better grasp the dynamic trend of the transformation and development of thermal power enterprises in the context of low carbon worldwide; the background of the transformation development of thermal power enterprises, the low carbon economic model, and the basic situation of the thermal power industry are reviewed and analyzed. Yearly quantitative distribution of literature, country (region) distribution, main source journal distribution, organization distribution, research hotspots, and frontiers are all analyzed, CiteSpace and Vosviewer are used to plot expertise area maps. The results show that the number of studies on the transformation and development of thermal power plants under the background of low carbon is on the rise in general, among which the contribution of China is the largest. Research articles have been published in 77 publications worldwide, mainly in the fields of chemistry, materials, and fuels. The framework of simple theories and research strategies has been completed. However, the research community is too targeted and there are few frontier branches. Based on technology development, process updating and process development, environmental remediation, electrochemical CO2 reduction, organic contaminants, active sites, and bifunctional electrocatalysts have become the leading research topics of thermal power plant transformation development. [ABSTRACT FROM AUTHOR]

Simple Summary: We provide a data classification and analysis method to estimate fire risk using facility data for thermal power plants. Experimental analysis is conducted on the data classified by the proposed method for 500 megawatt (MW) and 100 MW thermal power plants. In this paper, we propose a data classification and analysis method to estimate fire risk using facility data of thermal power plants. To estimate fire risk based on facility data, we divided facilities into three states—Steady, Transient, and Anomaly—categorized by their purposes and operational conditions. This method is designed to satisfy three requirements of fire protection systems for thermal power plants. For example, areas with fire risk must be identified, and fire risks should be classified and integrated into existing systems. We classified thermal power plants into turbine, boiler, and indoor coal shed zones. Each zone was subdivided into small pieces of equipment. The turbine, generator, oil-related equipment, hydrogen (H2), and boiler feed pump (BFP) were selected for the turbine zone, while the pulverizer and ignition oil were chosen for the boiler zone. We selected fire-related tags from Supervisory Control and Data Acquisition (SCADA) data and acquired sample data during a specific period for two thermal power plants based on inspection of fire and explosion scenarios in thermal power plants over many years. We focused on crucial fire cases such as pool fires, 3D fires, and jet fires and organized three fire hazard levels for each zone. Experimental analysis was conducted with these data set by the proposed method for 500 MW and 100 MW thermal power plants. The data classification and analysis methods presented in this paper can provide indirect experience for data analysts who do not have domain knowledge about power plant fires and can also offer good inspiration for data analysts who need to understand power plant facilities. [ABSTRACT FROM AUTHOR]

The occupational stressors has an effect on overall health and dental health. Oral health is a vital aspect of general health. The current study was performed to assess the periodontitis among thermal power station workers in South India. Pilot study was done for 52 mine workers and based on the periodontal disease prevalence among them, the sample size was calculated as 603 subjects. The data collection was done using WHO 1997 proforma. Among the total study population, about 92 (30%) thermal power station 1 workers and 83 (28.1%) thermal power station 2 workers had pocket 4-5 mm, one (0.2%) thermal power station, 2 worker had pocket 6 mm or more thermal power station I workers, and 23 (7.8%) thermal power station 2 workers had 6 - 8 mm attachment loss. Only 1 (0.3%) thermal power station I worker had 9 - 11 mm attachment loss. In the current study, nearly 70% mine workers had calculus, nearly 30% had pocket 4-5 mm, and only 0.2% Mine II workers had pocket measuring 6 mm or more. [ABSTRACT FROM AUTHOR]

The Muara Karang steam power plant is one of the power plants in Indonesia which is managed by PT PLN Nusantara Power as a state-owned company. In carrying out its business, it has potential impacts on the environment, one of which is on biodiversity. The aim of this research is to analyze the potential of biodiversity resources by conserving critical land in the Organic Forest, Megamendung, Bogor, Indonesia. The method used is a natural forest model scenario including organic farming, reforestation, and sustainable organic farming in a natural rehabilitation process. Rehabilitation is carried out using an agroforestry system, intercropping between forestry and agricultural crops, and fertilization using manure. This planting was carried out by the community as a form of empowerment which succeeded in creating jobs as farmers and participating in managing the forest. As a start, 3,000 tree seeds and intercrops such as edamame, corn, cassava, and taro have been planted. The results of this research in monitoring in 2022, the proportion of tree habitat increased from 40% to 54%, the diversity index (H') of birds increased from 2.17 to 3.22, H' of mammals from 1.76 to 2.05, H' of herpetofauna from 2.08 to 2.82, and H' of arthropods from 3.73 to 3.87. [ABSTRACT FROM AUTHOR]

In this paper, we explore the ways that a STEAM-focused summer program for Indigenous youth supported learning in accordance with Indigenous axiologies (what we value esthetically or morally), ontologies (what we believe to be real and how we enact those beliefs), and epistemologies (what we know and how we know it) or AOE. Part of these AOEs include enacting kin relationships through recognizing the personhood of more-than-human beings. We posit that (1) our socio-cultural, political, and ethical orientations regarding human-nature relations affect our behaviors and that (2) shifting the way we view nature (e.g., recognizing plant personhood) may be a powerful contributor to more equitable climate futures. We present a case study of the relationship between a human child, Talon, and a plant called Stinging Nettle. We specifically move to answer: Did the program design support engagement in the recognition of plant personhood? If so, in what ways? The paper describes six dimensions of recognizing plant personhood. Findings illustrate how the program design resulted in the development of a strong human-plant relationship. We discuss implications for STEM and climate change education in supporting ecologically sustainable living and decision-making. [ABSTRACT FROM AUTHOR]

The radical decline in climatic conditions coerces the world to take steps progressive toward implementing green energy technologies in all facets. The electric vehicle is one such huge leap toward providing a pollution‐free environment to the future generation, but the charging techniques in most cases utilize the power that is obtained using thermal power stations, and so on. This concludes it to be not completely green energy, therefore in this paper, considered two far‐reaching sources viz. photovoltaic and wind energy storage systems. The sources are also supported with the presence of an additional storage unit of battery energy storage system (BESS) and the overall system is managed by energy management system (EMS) that is designed using a simple state flow algorithm instead of complex machine learning methods. The electric vehicle (EV) is charged using wireless power transfer technology. The model is built using MATLAB—Simulink software and the simulation results are validated against the physical calculation carried out over the equivalent circuit model reduction method. The values were taken from the TATA Nexon EV for consideration and the output values are 400 V and 15 A to be provided for the charging of the EV at the receiving end of the wireless charging. [ABSTRACT FROM AUTHOR]

The proposals are based on an analysis of the current state and methodologies of corporate risk management with an emphasis on management according to internationally recognized ISO 3100X standards and their revision, as well as the requirements of revised ISO standards for quality management, environment, safety, etc. related to risk management. The Deming cycle (Plan-DoCheck-Act) of continuous improvement is a methodological tool for building a management system, whether for a partial aspect or integrated, which greatly facilitates the integration process. Significant support for the integration of management systems is a unified element structure of the latest revisions of ISO standards according to Annex SL for quality ISO 9001, environment, ISO 14001, occupational health and safety ISO 45001, information security ISO 27001, but also others. When implementing management systems according to these standards, it is recommended to use the latest ISO standard 31000: 2019 Risk Management - Guidance in connection with the management of individual risks. Although this standard does not have a 10-chapters structure according to Annex SL as well as other standards, it is fully integrated into the system. It has 6 chapters and chapters 4. Principles, 5. System, 6. The process contains recommendations that can be integrated with the requirements of the chapters of the ISO standards for environmental management, quality, safety and health at work, health and safety, information security. The identification and evaluation of aspects of impacts and risks is an input to building management systems of an organization according to internationally recognized standards, whether for partial aspects or an integrated system. The most important aspects impacts and risks, whether technical, economic, environmental, safety, information and others are reflected in the management system in policies and objectives. In this context, it is useful to draw up a Register of Aspects, Impacts and Risks for organizational processes, and if it is an integrated management system, an integrated register is needed. As part of our research, a generally applicable guide to the preparation of a more exact integrated register was proposed as a basis for building an integrated management system. The register form includes 10 columns with their specification and quantification and was applied in the operating conditions of the Vojany thermal power plant in the implementation of the quality and environmental management system according to the relevant international standards. At the end of the paper, the presented solution specifies possible benefits from the implementation of an integrated management system built according to internationally recognized ISO standards. [ABSTRACT FROM AUTHOR]

The intermittence of renewable energy sources increases the importance of the effective load-tracking ability of power plants. Coordinated control between boiler and turbine systems is the uppermost layer of a thermal power plant control to follow the load demand. In this paper, a supplementary controller is proposed based on the One-Step Ahead strategy for coordinated control of thermal power plants. After a plant model is developed offline from a step response test, the optimized control of the One-Step Ahead strategy is applied to the boiler feed-forward (BFF) signal to control the electric power output and the main steam pressure simultaneously. Simulation with a 1000 MW ultra-supercritical (USC) once-through type power plant is performed. The results show that the error of Mega-Watt Output (MWO) was reduced to 78~95%, and settling time was reduced to 64~79% from conventional coordinated control by adding the proposed supplementary controller. [ABSTRACT FROM AUTHOR]

Biomass combustion or co-firing in modern coal power plants for steam/power generation is a carbon–neutral process, but it could pose acidic air pollutants and ash-related challenges like slagging and fouling. This paper aimed to evaluate the energetic potential of six special crop husk residues (i.e., chestnut husk, coffee bean husk, cocoa pod husk, coconut shell, peanut husk, and water caltrop husk) through their thermochemical characterization and thermogravimetric analysis (TGA) study. The thermochemical characterization included the proximate analysis, ultimate (elemental) analysis, calorific value (higher heating value, HHV), and elemental compositions of ash. The results showed that these residues have the potential for the biomass feedstocks in the boilers due to the large carbon contents (43.81–49.27 mass%), low ash contents (e.g., 0.27 mass% for coffee bean husk), and high HHVs (18.65–21.26 MJ kg−1). The HHVs were higher for the biomass husk residues with a low O/C ratio and low ash content. The chlorine, nitrogen, and sulfur contents, responsible for acidic air pollutants, were less than 1% except for chlorine in caltrop husk (1.59%). However, based on the relevant slagging/fouling indices using the data on the ash compounds and chlorine content, it was revealed that the ashes of chestnut husk, cocoa pod husk, and water caltrop husk had a high slagging tendency mainly due to the high contents of potassium and chlorine. In contrast, co-firing of biomass husks—coffee bean husk, peanut husk, and coconut shell, with coal could result in lower emissions of particulates, oxides of sulfur- and chlorine-bearing pollutants, and reduced slagging and fouling tendencies. In this regard, coconut shell is a very clean biomass fuel due to its excellent properties and large amounts. [ABSTRACT FROM AUTHOR]