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The incineration of high‐moisture solid residues generated at the recycling paper mills represents an energetically unfavourable method of resource utilization. Alternatively, hydrothermal pre‐treatment is considered. In this study, low‐value paper sludges from three different recycling streams were hydrothermally carbonized at 205, 225, and 245°C for 3 h. The raw feedstocks and derived hydrochars were analyzed for energy properties, chemical characteristics, surface morphology, functional groups, and combustion performance employing energy densification and mass yield quantification, scanning electron microscopy, elemental analyzer, Fourier‐transform infrared spectroscopy, and thermogravimetry. The increase in reaction temperature was reported to cause a decrease in mass yield and an increase in energy densification and calorific values corresponding to 5.98%–49.35% and 10.10%–58.51% for raw fibre rejects and final sludge‐derived hydrochar, respectively. Hydrothermal carbonization (HTC) had a non‐significant influence on the energy densification of primary clarifier sludge‐derived hydrochar. Higher reaction temperatures favoured the rate of dehydration and decarboxylation, leading to hydrochars with lower H/C and O/C ratios, thereby enhancing the overall fuel properties. The low‐nitrogen and low‐sulphur fuels obtained validated the effectiveness of HTC treatment to produce high‐quality cleaner solid fuel. The burnout temperature was mostly reduced with an increase in HTC temperature. At HTC‐205 and 225°C, the ignition temperature and the combustion performance increased as a result of the HTC reaction mechanisms. HTC effectively recovered hydrochar with increased carbon content, improved energy densification, and good combustion adequacy. Hydrochar derived from recycling mills may play a role in the energy sector as a substitute for coal or in co‐combustion at coal‐fired power plants. [ABSTRACT FROM AUTHOR]

A run‐of‐the‐river power plant is a renewable energy source used for electricity production. Its power output depends on the varying water flow rate over time, which can impact the reliability of the electric network. Previous research has not studied the effects of water flow rate and temperature variations on the hazard rate of the plant's components. This paper addresses this gap by investigating the impact of these variations on the reliability of electric networks with run‐of‐the‐river power plants. The analysis considers the hazard rates of the plant's components, incorporating the relationship between hazard rate and temperature based on the Arrhenius law. Parameters such as power output, current, power loss, operating temperature, and hazard rate are calculated for different water flow rates and ambient temperatures. Numerical simulations on a test system are conducted to examine the influence of water flow rate and temperature on the reliability indices of the electric network. The results demonstrate that water flow rate and temperature significantly affect the hazard rates of run‐of‐the‐river power plants. This highlights the need to consider these factors in the reliability analysis of electric networks incorporating these renewable resources. [ABSTRACT FROM AUTHOR]

In the context of a low‐carbon economy, considering the output uncertainties of the renewable energy sources and the fluctuation of electrical price, the cost–benefit analysis is proposed for multi‐investor virtual power plant (VPP) under different risk preferences, and multi‐investor VPP capacity sizing problem is researched. First, the structural organization and flexible regulation characteristics of multi‐investor VPPs are analyzed. Second, integrated model and cost–benefit analysis indexes of VPP are built. Third, an optimal capacity sizing model of multi‐investor VPP is established, aiming at income maximization. Game theory is used to configure the distributed generators in the VPP under various cooperative modes and noncooperative modes of multiple investors. Fourth, according to the installed proportion of each distributed generator and the risk preference coefficient of each investor, the income allocation correction model based on the improved Shapley value method is proposed to stabilize the optimal VPP alliance. Finally, the demonstration project in the animation industry park of Sino‐Singapore Tianjin Eco‐City is employed as representative scenarios, which is used to validate the effectiveness of the proposed model. The results prove that the method proposed in this paper can guide knowledge for the investors with different risk preferences when planning the optimal capacity of multiple distributed generators in the VPP. [ABSTRACT FROM AUTHOR]

The accumulation of snow is one of the essential reasons for the significant decrease in the power generation efficiency of PV stations in winter. For this reason, this paper firstly provides a detailed review of the current research into the physical processes and shedding reasons for the natural melting of snow on PV module surfaces. Then, several common techniques to promote snow and ice melting on PV surfaces are discussed, and the feasibility and shortcoming of ultrasonic technology in removing high‐density snow and ice are analyzed in detail. Finally, this paper proposes two snow sensing technologies for PV modules, namely, image processing method and interdigital capacitance method. Among them, the image method based on fixed camera and UAV detection is more suitable for wide area PV power stations, while the interdigital capacitance method is helpful in obtaining snow characteristic parameters, such as icing type and LWC. The relevant research has certain reference significance for PV power stations to formulate a more reasonable snow removal plan and power generation forecast. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Summary: Coal‐fired thermal power plants play important roles in daily life but are vulnerable to earthquakes. This paper presents a novel cable‐damper stopper with linear damping and carries out a series of shaking table tests to evaluate its performance on a 1/25‐scaled coal‐fired thermal power plant. The stopper consists of a cable, a linear viscous damper and a steel block attached to the boiler. The seismic responses of the structure equipped with different sets of cable‐damper stoppers which are of different damping coefficients and diameters of cables were studied and evaluated, where three seismic ground motions with two intensities were selected as input motions. The obtained acceleration and displacement responses of the support structure and the boiler reveal that the stopper cable effectively restrains the relative displacement between the boiler and the support structure. Furthermore, it can be found that the damping affects the seismic protection performance of the stopper depending on the intensity of the boiler vibration. In the paper, the working mechanism of the stopper is also analyzed based on the test data. It turns out that the stopper is more effective when it works under severe earthquakes. [ABSTRACT FROM AUTHOR]

Virtual power plant (VPP) can aggregate distributed energy resources (DER) and controllable loads to participate in the bidding of electricity market and carbon trading market. However, the uncertainty of renewable power production brings high transaction risks to VPP. Given this background, this paper proposes a novel Wasserstein‐distance based two‐stage distributionally robust chance constrained (DRCC) bidding model for VPP participating in the electricity‐carbon coupled market. The uncertainties are modelled as an ambiguity set based on Wasserstein distance, in which the two‐sided chance constraints are guaranteed satisfied. In the first stage, VPP's revenue is maximized according to the forecast information. In the second stage, the re‐dispatch measures are determined to hedge against the perturbation of uncertainties under the worst‐case distribution within the ambiguity set. Finally, a reformulation approach based on strong duality theory and conditional value‐at‐risk (CVaR) approximation is proposed to transform the DRCC problem into a tractable mixed‐integer linear programming (MILP) framework. Case studies are carried out on the IEEE 30‐bus system to verify the effectiveness and efficiency of the proposed approach. [ABSTRACT FROM AUTHOR]

Since the liberalisation of India's energy sector began in the 1990s, the government has developed several novel techniques to make coal an attractive asset for investors. The pharaonic Ultra Mega Power Plant Project (UMPP) program is one such technique which secures finance capital, land, and environmental clearances for coal‐fired power plants. Drawing upon the analytic of assemblage, this paper tracks how the Cheyyur UMPP, one of the largest proposed coal‐fired power plants in the world, has been disassembled by a range of interdependent elements, from Right to Information (RTI) activism and environmental litigation to the perception of litigation risk and the materiality of coal. In pursuing an analysis of the events and elements which have led to the Cheyyur UMPP being disassembled, this paper calls for greater attention to the vulnerabilities, limits, and instabilities of coal assemblages. [ABSTRACT FROM AUTHOR]

To effectively utilize ventilation air methane (VAM), it is proposed to pass it into the boiler of the coal‐fired power plant for mixed combustion. However, the different types of thermal coal utilized present distinct characteristics when mixed with VAM. In this paper, lignite, bituminous coal, and anthracite are selected to study the CH4 conversion rate, system ignition temperature, and NO emission characteristics of the VAM‐pulverized coal coupled system on a fluidized bed experimental platform. The experimental results show that the ignition temperatures of VAM are 748, 736, and 732 °C when the CH4 concentration is 0.25, 0.5, and 0.75%. After the addition of thermal coal, the ignition temperature decreased significantly. When the CH4 concentration is 0.25%, the ignition temperature of the lignite‐VAM system is the lowest, which is 450 °C. Anthracite has the strongest catalytic effect on CH4 combustion. When the heating rate is 5 °C /min, the reaction rate of CH4 is the fastest in the anthracite‐VAM coupled system. Under laboratory conditions, the peak NO concentration in the coal‐VAM coupled system was lignite > bituminous coal > anthracite at different CH4 concentrations, and the CH4 in VAM had a reducing action on the NO generated during mixed combustion, with a stronger reducing effect observed as the CH4 concentration increased. The results of this study can lay the foundation for the industrial application of the mixed combustion of VAM and thermal coal, and be of great significance for solving the practical problems caused by the change of boiler coal types. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Coal‐fired thermal power must be flexible to enable the grid absorption of inconsistent photovoltaic (PV) and wind power. Combined heat and power (CHP) coal‐fired plants are the primary source for district heating systems. This paper uses a 330 MW subcritical CHP unit as an example to carry out the study. With the promotion of building energy efficiency, when the thermal index is reduced to below 20 W/m2, the low‐load operation of CHP can meet the wind power and PV feed‐in demand and guarantee residential heating without the need for flexibility modification. Meanwhile, more renewable energy generation can reduce carbon emissions from the power supply, further contributing to reducing carbon emissions from buildings. The impacts of different envelope parameters and supplementary heat sources on building carbon emissions are also studied. The conclusion shows that the degree of their impact on carbon emissions ranks as ESMs (energy supply modes) > Factor D (infiltration N50) > Factor A (external wall heat transfer coefficient) > Factor C (window heat transfer coefficient) > Factor B (roof heat transfer coefficient). When the building's heating energy consumption gradually decreases, the distributed heat pump unit can replace the coal‐fired boiler to supply the peak heat load demand. In the future, China's district heating systems can be gradually changed from the current CHP and coal‐fired boilers to CHP and distributed heat pumps. [ABSTRACT FROM AUTHOR]

Electrostatic precipitator (ESP) is the main equipment for flue dust control of coal‐fired power plants in China, accounting for about 70% of the total currently. In this paper, energy efficiency data of ESP, including 202 sets before ultra‐low emission and 45 sets after ultra‐low emission are systematically studied and analyzed by using the research method of field testing and technical investigation. The results showed that after ultra‐low emission, the energy consumption and converted CO2 emission of ESP in coal‐fired power plants increased significantly, and the specific power consumption and energy consumption corresponding to unit mass particulate matter (PM) removal increased by 49.61% and 139%, respectively, and the converted CO2 emission increased by 1.67 × 10−4 kg CO2/m3 and 31.12 kg CO2/t PM on average. The energy consumption of low‐low‐temperature ESP (LLT‐ESP) was positively correlated with its emission reduction range. Before and after the gas cooler operation, the power consumption, specific power consumption and energy consumption corresponding to unit mass PM removal increased by 8.06%–38.68%, 10.66%–60.14% and 7.23%–62.98%, respectively, and the CO2 emissions corresponded increased by 26.29–691.81 kg CO2/h, 0.46–2.18×10−4 kg CO2/m3, 1.10–23.62 kg CO2/t PM, respectively. LLT‐ESP had a great possibility to optimize the operation for energy‐saving and carbon‐reduction, because when the high voltage power supply operated on the maximum output mode and the energy‐saving mode, the drop of power consumption and specific power consumption was around 52.00%–58.23%, 52.02%–58.29%, respectively, and the CO2 emission reductions corresponded was 1,039.25–1,359.35 kg CO2/h, 2.71–3.58×10−4 kg CO2/m3, respectively. LLT‐ESP also had the great optimizing possibility for energy‐saving and carbon‐reduction during low load operation, as when the load reduced from 100% to 50%, the specific power consumption and energy consumption corresponding to unit mass PM removal increased by 5.05%–45.50%, 6.59%–63.90%, respectively, and the CO2 emissions corresponded increased by 0.38–2.44×10−4 kg CO2/m3, 6.76–45.98 kg CO2/h, respectively. The operation energy consumption can be effectively reduced by integrated use of multiple electric dust removal technologies, such as compared with LLT‐ESP technology, the power consumption, specific power consumption and energy consumption corresponding to unit mass PM removal of "low‐low‐temperature + moving electrode+ electrostatic agglomeration" decreased by 37.88%, 30.08% and 45.29% respectively, and the corresponding CO2 emission decreased by 697.22 kg CO2/h, 1.87×10−4 kg CO2/m3 and 32.98 kg CO2/t PM, respectively. The current national standard GB 37484‐2019 is no longer applicable to the energy efficiency evaluation of the ESP in ultra‐low emission units. This study can provide data support for the revision of national standard GB 37484‐2019 and the collaborative efficiency of coal power plant pollution reduction and carbon reduction. © 2023 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The development of new energy vehicles has become an important means by which China can continue to grow as a major automobile manufacturing powerhouse while joining the worldwide effort to tackle climate change. This paper uses Chinese‐listed new energy vehicle companies during 2015–2019 as the research sample and examines the impact of government subsidies on enterprise innovation, with the technical background of CEOs as an important moderating factor. We also analyze the extent of this moderating role within different institutional environments and corporate ownership structures. The results show that government subsidies can encourage new energy vehicle enterprises to increase innovation investment, and CEOs' technical backgrounds can strengthen this relationship. Compared with regions with better institutional environments, the moderating effect of CEOs' technical backgrounds is more obvious in regions with poor institutional environments, and when compared with state‐owned enterprises, the effect is more obvious in the private sector. We propose a list of government and internal enterprise policies that would make use of the insights gained from our research results. [ABSTRACT FROM AUTHOR]

Nitrogen oxides (NOx) are one of the air pollutants, mainly from coal‐fired power plants, industrial furnaces, etc. In order to control NOx, reduce the preparation cost of denitration catalyst. Selective catalytic reduction is currently the most effective and mature technology for removing NOx. In this paper, solid waste fly ash was used as catalyst carrier, shear reactor was used to prepare Mn−Ce/FA catalyst, and successfully applied to SCR denitration. The catalyst was characterized by SEM, XRD, FTIR, XPS. The results showed that the catalyst prepared by shearing had more dispersed active components. When the power was 80 W, time was 20 min, rotation speed was 120 r/min, and the molar ratio of Mn−Ce was 1 : 1, the optimal catalyst was prepared. Under these conditions, the catalyst had the best activity and strong stability, the denitration performance was the best, up to 82.6 % within 30 min. The introduction of SO2 still showed high catalytic activity and stability, and the removal rate reduced to 73.21 %. After SO2 was stopped, the removal rate rebounded to 77.89 %. Also, Mn−Ce/FA catalyst had good cyclability and stability in the denitration process. [ABSTRACT FROM AUTHOR]

The utilization of residual energy of high‐temperature flue gas at the tail of coal‐fired boilers has attracted widespread attention in recent years. The thermal performances of the boiler and system in different split‐flow layouts still need to be analyzed and compared in detail. Thermodynamic models for four different splitting layouts of supercritical carbon dioxide (S‐CO2) Brayton cycles tailored for coal‐fired power plant are built and validated. By performing the process simulations, the effects of splitting ratios on the system thermal performance are comparatively analyzed when the secondary split point and the confluence point are set at different positions. The maximum system efficiency of the two‐split layout with a secondary splitting point at the inlet of the cold side of the high‐temperature recuperator (HTR) can be obtained within a range of secondary split ratio. The maximal and minimal boundaries are determined by the exhaust flue gas temperature and the heat capacity match in the recuperators, respectively. The mass flow rate of the cold stream in the low‐temperature recuperator (LTR) should be kept unchanged by constraining the sum of primary and secondary split ratios, the constant to prevent the cycle efficiency from decreasing dramatically, if the splitting layout with the split point at the outlet of the main compressor (MC) is used. The two‐splitting layout with a secondary splitting point at the inlet of the cold side of the HTR has the best performance by comparing the system efficiencies of different layouts. If there are any improved coupling approaches of the S‐CO2 Brayton cycle and boiler, this paper can provide the reference for the selections of the split ratios. [ABSTRACT FROM AUTHOR]

A multi‐model predictive control strategy based on kernel fuzzy c‐means (KFCM) clustering and integrated model is proposed for the complex problem of rapid and accurate control of ammonia injection in selective catalytic reduction (SCR) denitrification systems of coal‐fired power plants under a wide range of variable load conditions. First, the SCR data samples are clustered using the KFCM clustering algorithm, and the number of clusters is determined by introducing the Xie‐Beni index. Second, the prediction model of the SCR denitrification system is established by an integrated modelling approach, and the sub‐learners of the integrated model are the genetic algorithm optimized back propagation (GA‐BP) neural network model and the least squares support vector machine (LSSVM) model. Third, a multi‐model prediction controller based on the particle swarm optimization (PSO) algorithm and the integrated model is designed and developed. To ensure the stability of the system, a model‐switching strategy based on the minimum Euclidean distance is proposed. Finally, simulation verification and industrial field application verification are fulfilled by comparing with proportion integral differential (PID) control and single model predictive control (MPC). The results show that the multi‐model predictive control method proposed in this paper can obtain higher control accuracy and better control stability and meet the control requirements for the long‐term operation of the SCR denitrification system. [ABSTRACT FROM AUTHOR]

The climatic risk consists of financial and environmental risks, predominantly evolutes from carbon dioxide emissions from coal‐fired power plants. We develop a climatic risk control model to investigate the coexistence of renewable energy and the post‐combustion carbon capture technology as CO2 reduction strategies. Additionally, our proposed framework explicitly considers the acceptance of such strategies based on a balance of electricity supply according to demand. This paper adopts an additive fuzzy mixed‐integer optimization approach to model uncertain parameters and determines the optimal solution focusing on business and the environment. Furthermore, we investigate the feasibility of such emission control strategies with scenario analysis that help to execute the country's emission reduction policies. The usefulness of our methodology is demonstrated using data from the coal‐based power sector in the Eastern part of India. Overall, with the proposed model, we can achieve 30% reduction in emission release, which provides strategies to the decision‐maker for investment towards sustainable development. [ABSTRACT FROM AUTHOR]

Human error can cause severe problems in industrial oil, gas, and chemical processes. Although human factors analysis and classification systems (HFACSs) for the oil and gas industry (HFACS‐OGI) and the small‐scale chemical industry (HFACS‐CSMEs) have been independently developed, there are some limitations in providing detailed information on the contributing factors. Therefore, a new HFACS must be developed that can be commonly applied to the oil, gas, and chemical fields. This paper develops an integrated HFACS that can be applied to the oil, gas, chemical, and power plants, called HFACS‐OGAPI, by analyzing 45 accidents that occurred in domestic and overseas oil, gas, chemical, and power plants, based on the HFACS‐OGI system. An integrated HFACS‐OGAPI that can be applied to the oil, gas, chemical, and power plants is developed. The framework effectively identifies the contributing factors by providing specific information on Tiers 1, 2, 3, and 4 for Levels 1, 2, 3, 4, and 5. The contributing factors are effectively identified by analyzing the BP Texas Refinery explosion (2005), the Kleen Energy natural gas explosion (2010), and the Aghorn Operating Waterflood Station accidents (2019) with the developed framework. A checklist suitable for the HFACS‐OGAPI is developed by considering the contents developed by the National Aeronautics and Space Administration and the Department of Defense to determine the contributing factors. The developed checklist is expected to effectively identify and improve on the causes of human error through periodic inspection. [ABSTRACT FROM AUTHOR]

The increasing demand for electric power is an established trend in China, of which coal power accounts for a large proportion. This paper proposes an inventory hub location model considering multi‐type coal to minimize the total transportation and inventory cost in a multi‐coal‐power supply chain. A second‐order cone programming method is adopted to convert the original model. The exact solutions of the small‐scale real case show that the model can greatly reduce the total costs by CPLEX. For real‐world large‐scale cases, a customized greedy randomized adaptive search simulated annealing algorithm is devised and tested to obtain near‐optimal solutions within a reasonable time. The research has strong practical guiding significance for the management of the thermal coal supply chain. [ABSTRACT FROM AUTHOR]

Energy conservation and efficiency enhancement are the options to achieve carbon neutrality in coal‐fired power plants. Wet electrostatic precipitator (WESP) is an important pollutant removal and energy consumption equipment in coal‐fired power plants, which emits a large amount of CO2 indirectly and has a great potential for emission reduction. In this paper, the emission reduction characteristics of multiple pollutants and energy consumption were analyzed by collecting 158 datasets of WESP. The results showed that WESP was effective at removing PM, PM2.5, SO3, droplets, and Hg with the following concentrations at the outlet: 1–10, 3, 1–5, 15, and 5 µg/m3, respectively. The emission factors of different pollutants were sorted in the descending order of size as droplets (average value 51.59 g/MWh), PM (19.15 g/MWh), SO3 (17.32 g/MWh), PM2.5 (8.21 g/MWh), and Hg (9.74 mg/MWh). Specific power/water/alkali consumptions were found as 0.5–2.5×10–4 kWh/m3, 10 × 106 t/m3, and 0.06–9.79 ×10–8 t/m3, respectively. These consumptions were negatively correlated with the inlet concentration of PM/SO3. The average annual emission of CO2 per unit installed capacity by the application of WESP was found to be 13.88 t/MW. It was estimated that the CO2 annual emissions by using WESP in coal‐fired power plants in China were 1.68×106 t. The CO2 annual emission reduction of 7.33×105 t could be achieved through grade 2 energy efficiency WESP (7.83 t/MW) of GB/T 37484‐2019. A further reduction of 3.18×105 t could be achieved if it could be controlled at grade 1 (5.20 t/MW). This study can provide a valuable reference for the subsequent operation of ultra‐low emission units to conserve energy and reduce CO2 emissions. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents an investigation on simultaneous freshwater production and CO2 capture using the flue gases of a 500 MWe coal‐fired power plant. Generally, a fan/cooler is used to reduce the temperature of flue gas before flowing into the absorber column of a CO2 capture unit. It has been replaced with a heat exchanger in this study. Seawater and flue gas were passed through the heat exchanger to raise the temperature of seawater and reduce the temperature of flue gas. The high‐temperature seawater was subsequently fed into a membrane distillation (MD) unit for freshwater production. The cold flue gas was directed to the CO2 capture unit. The heat exchanger and CO2 capture unit were modeled with Aspen Plus software. Whereas MATLAB software was used to develop and solve the MD mathematical model software for freshwater production. The seawater flow rate was varied from 4000 L/min to 7000 L/min in the heat exchanger. As a result, the flue gas (flow rate 781.6 t/h) and the outlet seawater temperatures were reduced from 27.498 to 22.360°C and 73.384 to 52.670°C, respectively. However, higher inlet seawater temperature in the MD unit produced more freshwater. An increase in inlet seawater feed temperature in the MD unit from 52.670 to 73.384°C increased the freshwater production from 211,956.5 to 299,244 L/day. Furthermore, the CO2 capture process has been analyzed by varying the methyldiethanolamine (MDEA) and piperazine (PZ) concentrations in weight% (45 and 5, 40 and 10, 35 and 15, and 30 and 20, respectively). It was observed that the energy requirement reduced from 3.55 to 3.26 MJ/kg CO2 by increasing the PZ content from 5 to 20 wt.%. At 15 and 20 wt.% of PZ content in the blended solution of MDEA/PZ, the energy required to regenerate the solvent was 3.31 and 3.26 MJ/kg CO2, respectively. PZ emissions from the absorber were also increased with the raising of PZ content in the blended solution. The energy requirement was not much higher at 15 wt.% than 20 wt.%. Therefore, MDEA/PZ solution (15/35 wt.%) was considered an optimal concentration. The reboiler duty was reduced up to 3.25 MJ/kg CO2 at 15/35 wt.% concentration with stripper pressure of 2.3 bar. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In the power plant boiler, the problems about the deterioration of the heat transfer performance of heat exchangers and the waste of steam caused by the inappropriate soot blowing operations need to be solved. In this paper, for the platen superheater, the model for detecting the ash fouling was established based on the heat loss analysis and the GA‐BP neural networks. The detection results have validated that the heat loss caused by fouling that was set as the detection indicator can reflect the actual fouling trend of the platen superheater. In addition, the optimization model for soot blowing was built by the model of maximum net heat profit per unit time and the proposed dynamic judgment method. The optimization results have shown that the heat transfer performance can be boosted significantly by the optimization model. Setting the cumulative increment of heat loss as the judging variable was much more reliable and can realize the timely modification of the optimum moment and duration of the soot blowing according to the actual working condition. [ABSTRACT FROM AUTHOR]

Solar‐aided coal‐fired power generation (SAPG) has been attracting more and more attentions in recent years. However, the multi‐objective optimization of SAPG system considering off‐design work conditions has not been fully studied. In this paper, a general system integration optimization method (GIOM) has been developed for integration schemes optimization, and Nondominated Sorting Genetic Algorithm‐II (NSGA‐II) algorithm is used for multi‐objective optimization of SAPG system. As a case study, a SAPG system that refers to a real 600 MWe supercritical coal‐fired power plant is optimized based on a typical day. By simultaneous optimization of both initial investment (P) and solar net electric generation (Esolar), the solar subsystem design schemes are optimized as Pareto optimal set. At last, to maximum Esolar/P, the final design scheme is selected from the Pareto optimal set, whose Esolar and P are 237.6 MWh and 113.5 M$, respectively. The results show that, the final design scheme is a heliostat field with instantaneous optical efficiency of 63.24% at the design point, the receiver power rating is 133 MWt, the tower height is 136.6 m, and distances of successive rows of the three zones are 13.6, 17.7, and 24.5 m, respectively. A larger or smaller size of solar subsystem is considered to be uneconomical. The investment, the solar net electric generation, and Esolar/P of the Pareto front are shown in Figure 9. It can be seen that the maximum value of Esolar/P is 2.09. The corresponding design scheme results are as follows: [133.0 (RPR), 136.6 (HT), 0.8(R1), 1.0 (∆R1), 1.3 (∆R2), 1.8 (∆R3), 2.1 (∆R4), 2.5 (∆R5), 2.5 (∆R6)]. That is to say, the final design scheme is a heliostat field with 133.0 MWt receiver power rating and 136.6 m tower height. [ABSTRACT FROM AUTHOR]

Due to ongoing urbanization and industrialization, the energy and electricity demand and consumption are rapidly growing in China, resulting in large air pollutant and greenhouse gas emissions. The coal‐fired power industry is a key to achieving synergistic reduction of air pollutant and carbon emissions. This paper quantifies and compares synergistic effects of technology and policy reduction measures in the coal‐fired power industry. Using 2158 coal‐fired power generators of different types at 833 coal‐fired power plants in 24 Chinese provinces as research samples, this study quantifies and assesses the synergistic effects of structural and technical emission reductions at coal‐fired power plants through top‐down analysis of structural emission reduction and bottom‐up analysis of technical emission reduction. Comparing the synergy coefficients of both types of emission reduction measures, it is determined that structural emission reduction has a significant positive synergistic effect on energy consumption, pollutant and carbon emissions, with no extra emissions and energy consumption. On the other hand, technical emission reduction results in the negative synergistic effect of CO2 emissions due to electric power consumption and chemical reactions emissions in end‐of‐pipe measures of emission control, which demonstrated that prevalent desulfurization measure WFDG synergistically led to 0.688 tons of CO2 and 5.132 MWh electric power consumption for 1 ton of SO2 removed. Therefore, the structural emission reduction is an important means for multi‐target energy conservation and emission reduction. It is necessary for technical emission reduction to reduce related negative synergistic effects while enhancing target pollutant removal. [ABSTRACT FROM AUTHOR]

The load‐shedding scenario describes an unscheduled load reduction in a power plant so that it produces only the electricity that is needed by the plant itself. The reason for such a scenario is a collapse of power supply in the transmission network. In the subsequent restoration of the electrical supply, different options are distinguished. An essential part of each option is island operating or black start capable thermal power plants. The load‐shedding scenario is complex and multilayered. If process steam is also decoupled during the load shedding, high exhaust steam temperatures in the turbine stages can lead to plant shutdown. In addition, component damage can be expected in thick‐walled components due to high temperature and pressure amplitudes. Thus, it can be shown in this paper that the lifetime losses are highest at the high‐pressure preheater 6 and at the deheater and that the process heat coupling cannot be operated with constant mass flow under all circumstances. In order to investigate these issues, a detailed model of a lignite power plant has been created, which was developed in Modelica for simulating and comparing scenarios for a variety of applications. The model comprises the entire water‐steam cycle including turbines, preheaters and pumps, as well as a very detailed boiler model including the air supply, coal mills, heating surfaces, and piping. Furthermore, the power plants' control system has been implemented in a very precise way. In addition, the study involves a calculation of lifetime consumption for specific components to evaluate the effects. In summary, it can be stated that this study examines the thermodynamic aspects during a load‐shedding scenario for the first time. It focuses on processes within the power plant and thus differs significantly from other studies on this topic, which approach the issue from the electrical grid side. [ABSTRACT FROM AUTHOR]

In coal‐fired power plants, the feed water treatment processes (FWTPs) supply qualified water to utility boilers. The faults of an FWTP may endanger the whole power plant. The classical PCA‐/KPCA‐based fault detection algorithms are valid mainly under single operation condition. When they are put to a practical FWTP, they cannot deal with the problems as treatment route switching, multiple operation conditions, process fluctuations, and process nonlinearity. In this paper, k‐means, wavelet denoise (WD), and KPCA are integrated together to form a new algorithm as K‐WD‐KPCA. It is expected to deal with the process nonlinearity through KPCA, cope with the multiple operation conditions through k‐means, and relieve the process fluctuations through WD. In the experiments on the data sets collected from a practical FWTP, the multiple operation conditions are classified into three categories; consequently, three KPCA models are trained and correspondingly scheduled for online condition matching. WD is further used to denoise the real‐time T2 and SPE statistics. Results show that the WD part of K‐WD‐KPCA algorithm can indeed lower the false alarm rate without reducing its fault detection performance. Finally, the proposed K‐WD‐KPCA algorithm is coded into a software platform and deployed to a coal‐fired power plant containing 2 × 1000 MW generation units. The effectiveness of the K‐WD‐KPCA algorithm is convinced through field application results. [ABSTRACT FROM AUTHOR]

The targets of limiting global warming levels below 2°C or even 1.5°C set by Paris Agreement heavily rely on bioenergy with carbon capture and storage (BECCS), which can remove carbon dioxide in the atmosphere and achieve net zero greenhouse gas (GHG) emission. Biomass and coal co‐firing with CCS is one of BECCS technologies, as well as a pathway to achieve low carbon transformation and upgrading through retrofitting coal power plants. However, few studies have considered co‐firing ratio of biomass to coal based on each specific coal power plant's characteristic information such as location, installed capacity, resources allocation, and logistic transportation. Therefore, there is a need to understand whether it is worth retrofitting any individual coal power plant for the benefit of GHG emission reduction. It is also important to understand which power plant is suitable for retrofit and the associated co‐firing ratio. In order to fulfill this gap, this paper develops a framework to solve these questions, which mainly include three steps. First, biomass resources are assessed at 1 km spatial resolution with the help of the Geography Information Science method. Second, by setting biomass collection points and linear program model, resource allocation and supply chain for each power plants are complete. Third, is by assessing the life‐cycle emission for each power plant. In this study, Hubei Province in China is taken as the research area and study case. The main conclusions are as follows: (a) biomass co‐firing ratio for each CCS coal power plant to achieve carbon neutral is between 40% and 50%; (b) lower co‐firing ratio sometimes may obtain better carbon emission reduction benefits; (c) even the same installed capacity power plants should consider differentiated retrofit strategy according to their own characteristic. Based on the results and analysis above, retrofit suggestions for each power plant are made in the discussion. [ABSTRACT FROM AUTHOR]

In this paper, a tower solar collector-aided coal-fired power generation ( TSCACPG) system is proposed and studied in order to save the fossil energy and protect the environment. The integration scheme of tower solar collector and conventional coal-fired power plant is proposed. Based on the simulation platform TRNSYS, the TSCACPG system model is established and the dynamic performance of the TSCACPG system with the operating mode of coal saving is studied. The TSCACPG system performances of 1 day and 1 year are all discussed by using the DNI data of typical year in Chinese typical city of Dunhuang. Then, the sensitivity analysis of the TSCACPG system is carried out by changing the heliostat field scale (the size of the molten salt tower also changes accordingly). The annual performance of the TSCACPG system is also acquired. In consideration of the economic costs, the heliostat field area with the maximum annual solar-to-electric efficiency is selected as the optimal value. The results show that, for the case studied, the optimal heliostat field area is 101,400 m2, and the maximum annual solar-to-electric efficiency is 16.74%. And under the optimal situation, the standard coal consumption rate of the original coal-fired power plant is reduced from 301.5 g/ kWh to 294.5 g/ kWh. [ABSTRACT FROM AUTHOR]

The aim of this paper is to specify the role of coal‐fired power plants (CFPPs) in the formation of global emissions/harmful pollutants and to discuss the benefits of current and future technologies to minimize environmental damage. In this regard, pollutant/emission reduction technologies from CFPPs are discussed in detail by considering the environmental and global warming aspects. Pollutant gases from CFPPs around the globe have always been the most important source of environmental concern in societies. In particular, due to the burning of the coal without taking the necessary precautions, the nitrogen in the coal and combustion air and the combustible sulfur components in the coal content are oxidized and released to the atmosphere as nitrogen oxides (NOx) and sulfur oxides (SOx). Another pollutant from power plants is carbon monoxide (CO). CO is a colorless, odorless, poisonous gas that can remain in the atmosphere for a long time. In addition, significant amounts of carbon dioxide (CO2) occur by virtue of the combustion of coal. CO2 emission is in the class of greenhouse gases causing global warming. As a result of this study, the factors causing the formation of harmful pollutants in CFPPs are determined and present and potential suggestions are provided for the environmental sustainability of such facilities. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

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Summary: Electric power system is one of essential lifeline systems for an urban community. An actual power plant building with typical coal‐fired power generation process is selected to be studied in this paper. The detrimental impacts on the seismic performance of the structural system induced by heavy coal bunkers and irregular bracing configurations are expected to be mitigated by using retrofit strategies. A total of three retrofit design schemes that employ the isolation and supplemental damping techniques are developed. The original design scheme of the actual thermal power plant building that adopts steel special concentrically braced frame as lateral‐force resisting system is used as benchmark for comparison purposes. Nonlinear response‐history analyses are performed, and the obtained seismic responses are compared. To better quantify the benefit of the considered retrofit strategies, seismic risk in terms of probabilities of exceeding designated damage states as well as the downtime are analyzed. For the studied thermal power plant building, the results show that the added damping system is more effective in seismic risk reduction than the isolation for heavy coal bunkers. Compared to the original structural system design, the use of supplemental damping system cut the downtime of the thermal power plant building at most 42%. [ABSTRACT FROM AUTHOR]

This paper describes a novel system of a water‐sparged aerocyclone (WSA) for fine particles (FP) removal in the air stream from a coal‐fired power plant. The effects of operating parameters, including inlet FP concentration (C0(FP)), water jet velocity (UL), and air inlet velocity (UG) on the removal efficiency of FP (REFP) were investigated. The change of morphology, particle size distribution, and content of heavy metals of the FP samples before and after removal in the WSA were also compared. The results show that the RE of the FP and PM2.5 can reach as high as 99.36 and 99 %, respectively, under optimal conditions. A regression removal model of REFP = 85.08 × ReG0.0187 × ReL0.0037 × (C0(FP)/ρFP)0.0048 was proposed to predict REFP, and the calculated REFP by the model is in agreement with experimental data with deviations of ±0.5 %. This new technology provides an alternative approach for FP removal from exhaust gas and exhibits significant potential for industrial application. [ABSTRACT FROM AUTHOR]

This paper reports a method of dynamic simulation parameter tuning for a coal-fired power plant using genetic algorithms (GA). GA is a search algorithm based on the mechanics of natural selection and natural genetics. GA also is one of the effective methods for optimization problems and it requires a formalization of problems and fitness function definition. Because the dynamic simulation can be repeated and the error between real data and simulation results is defined by a fitness function, it is reasonable to consider genetic operations. To satisfy environmental laws and regulations, the control of NOx emission is important for the operation of power plants. Therefore, an NOx analytical model is designed and used for the dynamic simulation at the change of loads, the kind of coal, and so on. In this paper, the optical parameters for the simulation are determined by GA. [ABSTRACT FROM AUTHOR]

Using a solid Na‐based sorbent is one potential option to decrease CO2 emission in coal‐fired power plants, and the CO2 sorption reactivity of Na2CO3/γ‐Al2O3 sorbent was improved by mechanically doping MgO into Na2CO3/γ‐Al2O3 in our previous study while the mechanism was not clear. In this paper, the CO2 sorption/desorption mechanisms of the promising MgO‐doped Na‐based sorbent prepared by the two‐step incipient wetness impregnation method were studied using a fixed‐bed reactor, together with characterizations of X‐ray fluorescence, nitrogen adsorption apparatus, field emission scanning electron microscopy, X‐ray diffraction, and thermogravimetric analyzer coupled with Fourier transform infrared spectrometer (TG‐FTIR). Also, the sorption behaviors were well described with Avrami's fractional‐order kinetic model. Results demonstrated that MgO not only dispersed on γ‐Al2O3 but entered γ‐Al2O3's lattice, leading to the formation of Mg‐Al mixed oxides for CO2 sorption. In addition, a new phase Mg6Al2CO3(OH)16·4H2O was produced during the CO2 sorption process, which plays a crucial role in facilitating the conversion of Na2CO3 to NaHCO3. The CO2 sorption capacity of MgO‐doped Na‐based sorbents is presumably determined by the trade‐off between microstructure and active component dispersion. The knowledge gained about the promotion mechanism of MgO provides fundamental direction for the synthesis of Mg–Al mixed oxides, supported with the developed microstructure for CO2 sorption enhancement of Na‐based sorbents. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This article compares the efficiency of the coal-fired steam-generated electricity in Great Britain, the U.S. and France in 1970. The authors selected this industry for close examination because it had experienced rapid technological progress, its output is homogeneous and the data available are comparatively good. They found that the average level and rate of growth of fuel productivity in Great Britain industry were less than in France and in the U.S. The authors were careful to state, however, that technological backwardness was not the only interpretation of this result. They were aware that partial productivity measures could be very misleading because the contribution of other inputs, particularly capital, is ignored. Furthermore, this paper shows that the percentage increase in output in Great Britain from 1949-63 was higher than that in France and in the U.S., while the percentage increase in capital, measured by generating capacity, was much lower than in France or the US. This difference could be interpreted as implying that the productivity of capital in Great Britain industry was rising relatively to that in France and in the U.S. and thus that the industry in Great Britain was technologically forward. However, there are other interpretations, because capital productivity is also a partial measure of productivity. Thus, this paper suggests that there is a need a measure of productivity which reflects the simultaneous influence of all inputs and output and a production function provides such a measure. This article also estimates production functions for this industry.

This research studies the effect of biomass densification on the co-firing of wheat straw with coal using a three-dimensional CFD model. The linear dependence of the relative oxidation rate constant (with respect to phenol) on the Hammett substituent constant was proven in a Hammett plot. GLO:G9N/01feb22:cjce24163-fig-0001.jpg PHOTO (COLOR): . gl B EDITOR'S CHOICE b B Liquid film thickness of two-phase slug flows in capillary microchannels: A review paper b Amin Etminan, Yuri S. Muzychka, Kevin Pope In recent decades, two-phase Taylor flow has received substantial attention from researchers due to its useful benefits in a wide variety of industrial and medical applications. [Extracted from the article]

During the degassing process of coalbed methane, the external loads could change the permeability of the coal seam by means of transient and permanent deformations, which dramatically influence the production efficiency of coalbed gas. Due to the ignorance of irreversible deformation of coal permeability, the gas extraction efficiency and the prediction of gas disaster in underlying mining need to be improved. Thus, it is better to clarify the permeability change characteristics with irreversible deformation of coal. In this paper, the influence of different loading paths on the permeability of gas‐containing coal was studied, and six loading paths were studied by employing a self‐designed triaxial cyclic loading system. The results of this study show that the permeability of gas‐containing coal samples would significantly change with different loading paths. Corresponding to the variation of mining pressure or periodic geo‐stress varying in the excavation of roadways, both an increase in the axial pressure and an increase in the confining pressure would cause a decrease in gas permeability. In addition, the permeability of gas‐containing coal would be damaged even when the external loads are removed. When given a constant strain loading, the permeability shows a "V"‐shaped change with increased strain, and the transversal point of permeability locates between the yield point and the peak intensity. Therefore, it can be concluded that external loads less than the maximum strength of coal would lead to permeability loss in the coal seam, vice versa, the permeability will be increased. Hence, research results contributes to improving the gas permeability and increasing the gas production from coalbed by imposing effective loads on original coal seams through mining speed control. How the external load influence the permeability of gas‐containing coal? How to improve the gas permeability and increase the coalbed gas production? [ABSTRACT FROM AUTHOR]

As the mercury emitted from coal combustion can lead to serious environmental issues, researchers pay more attention to the content, distribution and occurrence of mercury in coal. In this paper, the content, distribution, and occurrence of mercury in the Permian tectonically deformed coals from Peigou Mine, Xinmi coalfield, Henan Province were investigated. A total of 18 bench samples were taken from No.2-1 coals seam in Peigou Mine, including 15 coal bench samples, two roofs and one floor. The mercury concentration, mineral composition, and main inorganic element content of 18 samples were determined by DMA-80 direct mercury analyzer, XRD, and XRF respectively. The results show that the mercury content ranges from 0.047 ppm to 0.643 ppm, with an average of 0.244 ppm. Though the coal seam has turned into typical tectonically deformed coal by the strong tectonic destruction and plastic deformation, the vertical distribution of mercury has remarkable heterogeneity in coal seam section. By the analysis of correlation between mercury and the main inorganic elements and the mineral composition in coal, we infer that majority of mercury mainly relates to pyrite or kaolinite. [ABSTRACT FROM AUTHOR]

Projects Expansion of Prague metro / Metroausbau in Prag Planning of Frankfurt main‐line railway tunnel starts / Planung für Fernbahntunnel Frankfurt startet New cavern power station at 2300 m above sea level / Neues Kavernenkraftwerk auf 2.300 m Seehöhe Offenburg tunnel is being planned digitally / Tunnel Offenburg wird digital geplant Construction of the longest water tunnel in Southeast Asia begins / Baubeginn für Südasiens längsten Wassertunnel TECO 2030 and Implenia develop solutions for emission‐free construction sites / TECO 2030 und Implenia entwickeln Lösungen für emissionsfreie Baustellen Strabag expands underground railway in Toronto / Strabag erweitert U‐Bahn in Toronto TELT assigned contracts for Mont‐Cenis base tunnel / TELT vergibt Bauaufträge für Mont‐Cenis‐Basistunnel Contract stage 1 of the Brenner Base Tunnel southern approach awarded / Los 1 der südlichen Zulaufstrecke zum Brenner‐Basistunnel vergeben Call for papers – Themes for the next issues of Geomechanics and Tunnelling / Themen für die nächsten Ausgaben der „Geomechanics and Tunnelling" [ABSTRACT FROM AUTHOR]

In this paper, we present improvements to postcombustion capture ( PCC) processes based on aqueous monoethanolamine ( MEA). First, a rigorous, rate-based model of the carbon dioxide (CO2) capture process from flue gas by aqueous MEA was developed using Aspen Plus, and validated against results from the PCC pilot plant trials located at the coal-fired Tarong power station in Queensland, Australia. The model satisfactorily predicted the comprehensive experimental results from CO2 absorption and CO2 stripping process. The model was then employed to guide the systematic study of the MEA-based CO2 capture process for the reduction in regeneration energy penalty through parameter optimization and process modification. Important process parameters such as MEA concentration, lean CO2 loading, lean temperature, and stripper pressure were optimized. The process modifications were investigated, which included the absorber intercooling, rich-split, and stripper interheating processes. The minimum regeneration energy obtained from the combined parameter optimization and process modification was 3.1 MJ/kg CO2. This study suggests that the combination of a validated rate-based model and process simulation can be used as an effective tool to guide sophisticated process plant, equipment design and process improvement. [ABSTRACT FROM AUTHOR]

Steady state concept has relevance in many fields, particularly in economics, engineering and thermodynamics. In a steady state system, the recent observed behavior will continue to be so in future. Energy and exergy analysis (first and second law of thermodynamic) in steady state condition of a thermal power plant provides in-depth information to find out areas for potential improvement in efficiency. This study deals with the performance analysis of a pulverized coal fired power plant using energy and exergy analysis in steady state condition. The overall plant performance is assessed by undertaking detailed modeling and simulating thermal cycle of the plant scheme. Off design energy and exergy utilization efficiencies and thermodynamic properties are assessed from the model simulation based on actual operating data collected from the plant Distributed Control System (DCS) at operating load of 460MW on 15-min average for a period of 8 h. The analysis revealed that the combustion chamber and boiler are the major source of exergy destruction with 40.29% and 53.20% respectively. Whereas gross energy and exergy efficiency of overall plant are calculated as 34.33% and 31.47% at 460MWgross generation as compared to the design rating of 37.77% and 34.53% respectively at 500MW. This paper deals with methodology and assessment of exergy destruction in the plant and how to reduce it. Simultaneously a comparison has been made of energy losses vis-a-vis exergy destruction of various plant components, which brings out advantages of using exergy method over energy method calculation. [ABSTRACT FROM AUTHOR]

With the increase in the proportion of new energy power generation in grids, there is an urgent need for the flexible operation of coal‐fired power plants. However, as the most efficient commercial coal‐fired power generation technology, the flexibility of double‐reheat ultra‐supercritical units is limited due to the steam temperature fluctuation in transient processes. To inhibit the steam temperature fluctuations, a data‐driven method, called long short‐term memory (LSTM) was introduced to model the dynamics of the steam temperatures of a 1000‐MW double‐reheat coal‐fired boiler. Moreover, an advanced controller was proposed by combining the LSTM‐based dynamic model and the model predictive control architecture. The results demonstrate that the LSTM model can be used to capture the time delay, multivariable coupling and non‐linear dynamics of the steam temperatures and the proposed controller exhibits excellent performance in steam temperature regulation. The superheated steam temperature fluctuation decreases from 15.4 to 9.8°C, the primary reheat temperature fluctuation decreases from 34.6 to 8.3°C, and the secondary reheat temperature fluctuation decreases from 41.4 to 8.8°C. The proposed method has good potential to stabilize steam temperatures during transient processes of wide‐range load cycling, and finally improves the flexibility of the double‐reheat ultra‐supercritical unit. [ABSTRACT FROM AUTHOR]

In this paper, the research literatures published in 2018 about power production waste generated from the coal‐fired power plants and nuclear power plants are reviewed. The wastes from coal‐fired plants include fly ash, flue gas desulfurization gypsum, spent selective catalytic reduction catalyst, hazardous trace elements, and the management, reuse, and disposal of these wastes are discussed. The treatment and disposal of wastes generated from nuclear power plants is also considered. Practitioner points: Reuse and disposal of coal‐fired and nuclear power plant waste is discussed in this annual literature review.Emission of hazardous trace elements from coal‐fired power plant is summarized.Radiological contaminant removal and radionuclides waste disposal is essential for nuclear power plant. [ABSTRACT FROM AUTHOR]

The nuclear phase‐out in Germany and the decarbonization of the energy supply are accompanied by a profound upheaval of the generation fleet. The decommissioning of large power plants and their replacement by decentralized, renewable generation plants (DG) as well as storage facilities leads to a shift in generation output from power plants connected to the transmission grid to a large number of renewable and decentralized plants connected to the distribution grids. This significantly impacts the approach to restore the interconnected system after a large‐scale blackout. In order to be able to plan and instruct the dispatch of generating power from the network operator's control centres when restoring the grid after a large‐scale blackout, two aggregation and forecasting methods differentiated by voltage level are presented. For larger farms connected to the high‐voltage grid, a structure‐based node approach is chosen; for the multitude of small and microunits connected to the medium‐ and low‐voltage grids, an area‐based approach is used. These methods do provide the network operator with active power/frequency management in the medium and long‐term range. The provision of fast frequency response (FFR) by inverter‐coupled units or storage systems stabilizes the frequency in the short‐term range. In this way, the frequency nadir following a load connection can be mitigated during network restoration, which accelerates the process. This is particularly relevant against the background of the nuclear and coal phase‐out, as it can compensate for the reduction in inertia and controllable feed‐in power caused by power plant shutdowns. In a case study, it is shown that in a grid island typical for the early phase of network restoration, the inertia of a 500 MW coal‐fired power plant can almost be replaced by a battery storage system of 50 MW which provides FFR. [ABSTRACT FROM AUTHOR]

Thermal power plants are the primary components of the electrical energy production industry. These plants come with certain challenges such as the production of harmful gases causing environmental pollution. This adds to global warming issues that are dangerous for the earth's ecosystem. Another crucial aim is the least cost operation of these power plants. Combining both of these results in the formulation of the Dynamic Economic Emission Dispatch (DEED). This is a multi‐objective, constrained, dynamic, complex, and non‐linear optimization problem. Traditional methods are insufficient to undertake the complexities of DEED due to challenges such as high computational requirements and local optimal solutions. Hence, for obtaining an optimal or near‐optimal solution to such a complex problem, a metaheuristic technique is greatly needed. Metaheuristic techniques offer several benefits to solving complex problems such as being robust, efficient, and overall, less affected by an increase in problem size. In this work, a novel hybrid Firefly Optimization Algorithm (FFA)—Grey Wolf Optimization Algorithm (GWO) has been proposed to solve the DEED problem. The complexity of the DEED problem is undertaken by involving constraints like power limits, power balance, and transmission losses. FFA‐GWO was applied on 5, 10, and 15‐unit standard test systems to meet 24‐h load demands. The optimal costs obtained in 5, 10, and 15‐unit standard test systems are 32264$, 1394212.615$, and 465373.448$ respectively. The comparison of results shows that the proposed framework surpasses the other methodologies in terms of reduced fuel cost and emissions. [ABSTRACT FROM AUTHOR]

Soot blowing is a common practice in coal‐fired power plants to ensure high energy conversion rate. The period of the conventional soot blowing is usually fixed, without the consideration of the load change and feeding coal switching. For the purpose of the soot blowing optimization, an approach to quantitatively evaluate the performance of soot blowing operations is proposed. Different heat exchangers' thermal resistances are calculated based on dynamic mass and energy balance to monitor their ash fouling deposition, and then, the boiler energy efficiency is predicted, adopting the rolling extreme tree boosting algorithm, and finally, the efficiencies with and without soot blowing are computed separately. With the data collected from a 350 MW ultra‐supercritical unit, pseudo‐online simulations are performed. The results show that even if the energy efficiency of the unit has exceeded 94%, a full‐process soot blowing may further increase the efficiency in some extent. For those subcritical units, the benefits should be higher. [ABSTRACT FROM AUTHOR]

Many power plants have been transformed and operated using low‐pressure cylinder near‐zero output (LP‐ZO) technology in China to make way for or provide necessary guarantees for renewable energy power generation. This research focuses on utilizing numerical simulation tools to improve the operational economy of units with LP‐ZO. The LP‐ZO thermodynamic and energy‐consumption model of a reference plant is established, and the momentum particle swarm optimization method is used to optimize the unit operations. Moreover, a model to determine the economic operational range of the combined heat and power plant with LP‐ZO is proposed. The results show that the LP‐ZO mode operations of the unit can reduce the minimum peak shaving rate and improve the flexibility of operations. The energy efficiency of the LP‐ZO mode is increased due to the recovery of a significant portion of the cold source losses. However, the irreversible exergy loss caused by large temperature difference heat exchange reduces the exergy efficiency of the unit. After operational optimization, the reference plant can save approximately 68.15 t d−1 of coal and reduce carbon dioxide emissions by about 27 t tce−1 d−1. This study provides an operating approach to the CHP plant with LP‐ZO unit in enhancing flexibility and economy. [ABSTRACT FROM AUTHOR]

This article focuses on how Chinese state actors understand the concept of sustainable development and implement policies for achieving the 2030 Agenda and the Sustainable Development Goals (SDGs). We examine the concept of Ecological Civilization (EC) that has gained momentum within China and examine how EC is constructed around certain organizational principles that are difficult to export without expanding Beijing's political control abroad. Based on the example of a coal‐fired power plant in Kenya, we also explore the potential opportunities EC presents for African stakeholders to hold Chinese state actors to account for China's normative principles. [ABSTRACT FROM AUTHOR]

BACKGROUND The fine particles emitted from coal-fired power plants has caused many health and environmental problems. Reducing the fine particle emissions from coal-fired power plants is of great significance. In this work, a novel process of heterogeneous vapor condensation after wet desulfurization was investigated to reduce the emission of fine particles. RESULTS The proposed novel process was realized via three different methods, and numerical calculation indicated that it was feasible. The experimental results showed that the temperature drop of desulfurized flue gas due to the added steam and cold air had a positive effect on the improvement in reduction of fine particles. The experimental results also showed that the heat exchange method was applicable to desulfurized flue gas at different temperatures. However, the steam addition method was more suitable for original desulfurized flue gas at lower temperatures while the cold air addition method has more advantages in the case of original desulfurized flue gas at higher temperatures. CONCLUSION The novel process proposed in this paper was feasible for industrial application. Under typical conditions, the fine particle emissions in the final discharged flue gas were reduced by 30-40% using this process. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The article focuses on how the tapping of residual heat at the Earth's core could yield a renewable source for energy production than what is currently produced by all the hydrocarbon resources around the world. Cited are geothermal energy for power production that currently exists in parts of the world, drilling challenges that cause oil and gas companies to show little interest in geothermal technologies, and the plan of Fervo Energy to use fibreoptic cables to monitor geothermal wells.

This study quantifies the environmental risk of a coal‐fired thermal power plant during operation by using environmental monitoring data, site surveys, and documented evidence. The following criteria are assessed: emissions (CO, SO2, NOx, PM10), impact on aquatic ecosystem (fish protection at cooling water intake and cooling water discharge temperature), and waste management (fly ash and bottom ash). Fuzzy sets were defined for each criterion, taking environmental regulatory context as an expert judgment. A survey was conducted with multiple stakeholders to determine the relative importance of risk factors. The survey results showed that the most concerned risks are SO2 and NOx emissions. The proposed method estimates the risk of each environmental criterion separately and then accumulates them into an environmental risk index (ERI). Accordingly, we assessed the Catalagzi coal‐fired power plant, which has been in operation on the Black Sea coast in northwestern Turkey. For this case study, the ERI resulted in a value of 0.78 (on a scale of 0–1), showing high environmental risk to the facility. Moreover, the applicability of the proposed framework was tested in several existing coal‐fired power plants using simultaneous measurements. All studied coal‐fired power plants in Turkey have unacceptable pollutants (PM10, SO2, and NOx) concentration levels indicating high health risk potential. The application of the integrated environmental risk assessment framework showed that new environmental regulations are needed in Turkey to specify more strict emission limits and to monitor CO2, fine particulate matter emissions, cooling water discharge, and fish protection at cooling water intake. [ABSTRACT FROM AUTHOR]

This section offers news briefs on scientific and chemistry research as of January 1, 2023. It includes the development of a donor-acceptor based porous polyimide photocatalyst using a catalyst-free one-pot polycondensation approach, a study on an alternative process for the conversion of polyethylene into propylene monomer, and a study on the effect of biomass liquefaction on the prices of glucose and xylose.