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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]

The construction of a new CFPP in Indonesia, which was located next to three existing power plants and utilized an existing discharge channel, faced the problem of insufficient capacity of the existing discharge channel to deliver water to four power plants. The problem occurred not only because of the overcapacity of the cooling water flow proposed by the new CFPP but also because of the small size of the culvert located in the discharge channel. This paper discusses several methods to overcome this problem by enlarging the culvert area or by removing the culvert from the channel and replacing it with a bridge. A hydraulic study was investigated using the HEC-RAS software by utilizing inputs obtained from the existing channel geometry and flow measurement data. It was found that additional culverts on both sides with a size of 2 m x 4 m and 3 m x 1 m could reduce the water level by 1.12 m and 0.39 m, respectively. Meanwhile, removing the culvert provided a significant water level reduction of 1.39 m. Enlarging the culvert was chosen as the solution to the discharge channel capacity issue since removing the culvert would require temporarily closing the channel during construction and stopping the operation of the existing power plant. [ABSTRACT FROM AUTHOR]

In the present paper, a rigorous analysis of a sub-critical steam power plant (120 MW) with reheating and regenerative configuration is presented, using energy and exergy analysis. The total work output from the power plant is 121.80 MW, which is close to the real value of 120 MW. The calculated energy efficiency of the steam power plant is 34.7%, while its exergy efficiency is 32%. In addition to it, energy analysis introduces the condenser as a major source of heat loss, on other hand, exergy analysis introduces the boiler as a major source of exergy destruction. Further to understand the effect of main steam temperature, reheating temperature and condenser pressure on the power plant, a parametric study is being conducted. [ABSTRACT FROM AUTHOR]

This paper investigated the performance of Malaysian power plants from the year 2015 to 2017 using Malmquist Total Factor Productivity (TFP) index, which is based on Data Envelopment Analysis (DEA). This approach offers substantial advantages as compared to other existing methods as it can measure productivity changes over time for a variety of inputs and outputs. Moreover, it comprises two primary components: the technical efficiency change and the technological change indexes that provide clearer insight into the factors that are responsible for shifts in total factor productivity. This study uses a single input, installed generation capacity (MW), and two outputs, average thermal efficiency (%) and average equivalent availability factor (%). These output-input data included ten main power plants: TNB Natural Gas, SESB Natural Gas, SESB Diesel, SEB Natural Gas, SEB Coal, SEB Diesel, IPP Semenanjung Natural Gas, IPP Semenanjung Coal, IPP Sabah Natural Gas, and IPP Sabah Diesel. The results have two significant implications for fossil fuel power plants in Malaysia. First, technological change was the primary factor in boosting the TFP performance of the fossil fuel power plants in Malaysia. Meanwhile, the decline in TFP performance in Malaysian fossil fuel power plants may be attributed, in part, to a lack of innovation in technical components as the results found that the average technical efficiency changes in 2015 - 2016 were at 146% and then dropped significantly to 2% in 2016 - 2017. Second, the average scale efficiency changes rose dramatically from -53% to 3% providing a significant contribution to the improvement of technical efficiency changes. The fossil fuel power plants become efficient as the power plants' size increases. This indicates that the size of a power plant positively impacts the performance of the TFP. [ABSTRACT FROM AUTHOR]

Air is the basis for the existence of life on Earth; but in the present age of modernization the degrading quality of air year by year, due to the growth of Industrialization, urbanization, automobiles, coal-fired thermal power plants, and various other factories is the matter of real concern. To predict the future growth of air pollutants numerous prediction models have been developed by researchers. Time-series ARIMA model although quite useful for forecasting but fails to handle non-stationary problems. Among all the existing forecasting models, wavelets along with the Machine learning models have proved to be very successful and have been widely used in various fields like mathematical modeling, signal recognition, image recognition, classification, function approximation, data processing, filtering, clustering, compression, robotics, and decision making. It is also used in the field of mathematical forecasting for developing efficient prediction models. This paper aims to develop a wavelet-ANFIS conjugation model and a wavelet-ARIMA coupled model along with the time-series ARIMA model for the prediction of black carbon concentration over the Raniganj, Jharia, and Bokaro coal mines of India, by considering a long term data obtained by NASA (http://nasa.gov/) and compare the results obtained by these models for determining the best prediction model. The validity of the results is tested with the help of error measures like RMSE, MSE, MAPE, MAE, and relative error. Results over the three sample sites conclude that the Wavelet-ANFIS conjugation approach outperforms the wavelet-ARIMA coupled approach and the simple time-series ARIMA model. [ABSTRACT FROM AUTHOR]

Dust emissions must be managed and reduced as much as possible to safeguard the environment and human health. Plate-type electrostatic precipitators have been used to decrease pollution in a number of sectors, particularly for applications needing massive volumes of gas to be dedusted at high dust concentrations and temperatures. This paper examines large-capacity plate-type electrostatic precipitators with three sections used in a coal-fired thermal power plant. Using simulations and experiments, the collection efficiency (in different ways of supplying sections, without and with sections rapping), the influence of dust resistivity and a dust layer on the surfaces of collection electrodes, the electrical parameters (voltage, current density, and space charge density) for the sections of the electrostatic precipitators, and the electrical parameters of the power sources (voltage, current, power, and power factor) are studied. A higher dust resistivity will cause a change in the shape of the voltage delivered to the sections, an increase in the average voltage from sections, and a decrease in collecting efficiency (by a few percent). A greater degree of intermittence alters the current-voltage characteristics of the sections, decreases the current across the sections, and improves collection efficiency. The density of space charges increases with the degree of intermittency and is highest at the input section. With increasing thickness of the dust layer on the collection electrodes, the collection efficiency increases. PM10 dust particles (which have a lower migration speed) are the hardest to collect with ESPs. When the sections are rapping, PM 20–30 dust particles are more difficult to collect because their migration speeds decrease significantly (compared to the situation when the sections are not rapping). The operation of the power sources of the ESP sections is dynamic, being controlled by the regulators, and the current (or current density), depending on the voltage characteristics, changes permanently (at intervals of a few seconds). The power sources of the sections are deforming consumers (the current is much different from the sinusoidal form). [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to examine the Chinese media's performance on reporting the issue of waste incineration power plants. The authors analyze the role of media in supervising relevant agencies and meeting the public need for related information.Design/methodology/approach This paper provides a content analysis of media reports toward waste incineration projects that follow the anti-incinerator event that occurred in Panyu district of Guangzhou city in 2009. The sample of this paper is based on 469 news reports that were released on the state-level search engine "ChinaSo.com" from January 2010 to June 2016.Findings Chinese media did not continue to focus on waste incineration issues after the anti-incinerator event in the Panyu district and there were only a few news reports about this topic. News reports of the information disclosure category accounts for the largest proportion but lack a depth of explanation. The proportion of news reports of media supervision and popular science information categories is relatively small.Research limitations/implications This paper is a pilot study of the media's reporting characteristics on waste incineration issues. There are some shortcomings in terms of sample selection and analysis, more in-depth assessment will be implemented and improved upon the future research. This study highlights the importance of media reports before or after relevant events in examining the media's social function. Besides, this study provides a new analytical idea for assessing the functions of the media on social public issues through media reports and the conclusions of this study have certain practical significance for the media to improve report behaviors.Originality/value This paper selects media reports on waste incineration power plant after the anti-incinerator event in Panyu district as media industry could pay much attention to relevant topics before the beginning of conflict events and continue tracking reports even after the events subside. This paper points out that Chinese media might increase sustained attention to waste incineration issues, strengthen the depth of interpretation, increase the supervision of relevant agencies, and enhance the relevance of the news reports to the public. [ABSTRACT FROM AUTHOR]

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In coal fired power plants, the metallic surfaces such as boiler tubes, walls of combustion chambers and other parts degrade by corrosion, erosion and abrasion. It happens due to the hot gaseous environment, steam oxidation and presence of hard minerals and impurities in the coal. It is very important to protect these surfaces from material loss, otherwise it would lead to increased repair and maintenance cost along with decreased plant efficiency. In this paper, the role of thermal spray coatings has been studied for the protection of different steel grades exposed to such degrading conditions at high temperatures, in coal-based power plants. A comprehensive study has been done by analysing and comparing the work done by various researchers. Some recent advancements related to coating materials and modification in coating techniques have also been studied. This paper would be helpful for the researchers to get an idea for selecting an appropriate substrate material and coating material for industrial applications. [ABSTRACT FROM AUTHOR]

This paper follows a practical approach to evaluate particulate matter emissions from biomass-fuelled power plants and analysis measurement uncertainties. Sixty-seven measurement reports from 11 biomass power plants, all equipped with fabric filters as dust control device, were analysed. Particulate matter emission measurements by gravimetrical standard reference method were chosen to provide the most reliable values to investigate the influence of bag filter parameters, such as media age or bag filter length. 92.1% of total dust emission measurements were below lower BAT-associated emission levels (BAT-AELs) for waste incineration. Data also showed that bag filter media older than 6 years can still secure very low dust emission levels. This work also gives a summary of findings and problems with uncertainty of automated measuring systems for dust emissions in biomass combustion applications in practice and quality assurance level one (QAL1) process related to very low emission levels such as lower best available techniques reference document (BREF) values. Practical examples on issues of continuous dust emission monitoring devices are also given. [ABSTRACT FROM AUTHOR]

This paper studies when and under what conditions the actions undertaken by the power plants involved in China's emission trading scheme (ETS) pilot became cost effective. Based on unique plant-level panel data and the difference-in-differences strategy, we identify that an insignificant initial reduction in cost efficiency occurred at the announcement stage for power plants in the pilot provinces; however, the cost efficiency of the pilot plants increased significantly following formal policy implementation. Additionally, the by-stage treatment effects differed across the pilot provinces due to localized market and non-market variations. Localized conditions of higher marketization, stricter policy enforcement, and lower carbon dependence enhanced this positive effect. The synthetic control results confirmed this variation in the policy effects. The carbon trading pilots resulted in improved efficiency in power plants in Shanghai, Guangdong, and Tianjin during the period 2013--2017, with an associated total cost saving of approximately 29.75 million RMB. To enhance the efficacy of the ETS policy, our findings suggest that the design of the policy should consider localized external factors. [ABSTRACT FROM AUTHOR]

Purpose: Many historical industrial activities, including coal mining and burning, have started near geogenic anomalies. It resulted in spatial overlap of anthropogenic and natural causes of elevated soil risk element contents. Here, distinguishing between anthropogenic and geogenic contributions cannot be achieved by conventional geochemical soil mapping, in particular, when only pseudo-total contents of risk elements were obtained, soil depth profiles were not acquired, and geological maps were not implemented. Methods: The local geology, topography and anthropogenic activities were taken into account when planning the soil sampling. Soil profiles were obtained using an auger sampler. Total contents of risk and lithogenic elements were obtained by X-ray fluorescence. Aqua regia extraction and inductively coupled plasma mass spectrometry (ICP-MS) were also used for analyses. Results: Coal use in the study area increased the soil contents of Cd, Hg, and Zn in 7 km circle east of the major power plant, typically to 2 × local background in topsoils. In the profiles closest to that plant, Cd emissions have already been translocated to soils below ploughed horizons that weaken the contamination signal in topsoils. The highest As and Pb contents in the Most Basin soils originated from a local geogenic anomaly and not coal burning. Conclusion: Common soil mapping projects and data mining routines cannot decipher anthropogenic contribution to the soil risk elements unequivocally, as it is demonstrated in this paper. When working in geogenically anomalous areas, a fundamental knowledge of the mechanisms controlling the content of risk elements in soils is required. [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]

In this paper, the quantile impact value (QIV) method was proposed as a weight coefficient distribution method to evaluate the influence of proximate analysis components on the low calorific value (LCV) of blended coals. Through data analysis technology, a new prediction model based on the QIV and the support vector regression (SVR) has been proposed to estimate the LCV. The comparisons between different analysis results reveal that the QIVW-GA-SVR model proposed here is consistently better than those models without weight coefficient distribution. [ABSTRACT FROM AUTHOR]

Near-zero carbon emission power (NZCEP) plants, consisting of gas-fired units; wind turbines; power-to-gas (P2G); and carbon capture, utilization and storage (CCUS) systems, have recently received a lot of attention due to their enormous benefits in reducing carbon emissions and increasing the consumption of renewable energy. However, a complex environment of interest and a combination of risks makes their development very slow. This paper establishes a risk analysis framework for NZCEP considering multi-stakeholder participation. Firstly, a synthetic risk factor system was constructed based on stakeholders' interests. Subsequently, interval type II trapezoidal fuzzy numbers were used and final weights were calculated from both subjective and objective aspects. Finally, we applied an acronym in Portuguese of the interactive and multi-criteria decision-making (TODIM) method to site selection to achieve a balance of interests of all stakeholders. In addition, a case study was conducted. The case result demonstrates that Zhengzhou in Henan Province is the best choice for a NZCEP power plant. A further finding is that government plays an important role in the development of NZCEP plants, with site selection results being the most sensitive to changes in the government's risk appetite. Moreover, human resources are an important factor in the siting of an NZCEP plant. [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]

This paper presents the modeling and simulation of an industrial-scale chemical looping combustion (CLC) power plant, including all process units (reactors, flue gas treatment units, heat integration, steam cycle, and CO2 compression train). A model of a 525 MWth CLC power plant was built using a rigorous representation of the solid fuel and oxygen carrier. Petcoke was considered the main fuel of interest in this study, and it is compared with other solid fuels. The flue gas compositions obtained with the model show that cleanup units are mandatory to comply with CO2 quality requirements. High levels of flue gas treatment, including 97.1% deNOx and 99.4% deSOx, are needed to achieve typical specifications for captured CO2. This is mainly due to the high level of contaminants in the fuel, but also to the absence of nitrogen in the CLC flue gas, thus resulting in higher concentrations for all substances. The high level of flue gas treatment is thus one of the important challenges for solid fuel combustion in CLC. The overall CO2 capture efficiency of the plant is estimated to be as high as 94%. Regarding the energy balance, a process net efficiency of 38% is obtained. Comparing the results with other available technologies shows that CLC exhibits one of the highest net plant efficiencies and carbon capture rates. CLC is thus a promising technology to produce clean energy from solid fuels. Finally, based on a sensitivity analysis, it is shown that process efficiency is mainly affected by the design and performance of the CLC furnace, the steam injection rate in the fuel reactor, the char separation efficiency, and the excess oxygen in the air reactor. [ABSTRACT FROM AUTHOR]

In order to solve the problem of the uneven distribution of the flow and ammonia concentration field in the selective catalytic reduction (SCR) denitrification system of a 660 MW coal-fired power plant, a three-dimensional computational fluid dynamics (CFD) model was established at a scale of 1:1. The existing flow guide and ammonia fume mixing device were then calibrated and optimized. The relative standard deviation of the velocity field distribution upstream of the ammonia injection grid (AIG) was optimized from 15.4% to 9.9%, with a reasonable radius of the deflector at the inlet flue elbows, and the relative standard deviation of the velocity field distribution above the inlet surface of the first catalyst layer in the reactor was optimized from 25.4% to 10.2% by adjusting the angle between the deflector and the wall plate of the inlet hood. Additionally, with the use of a double-layer spoiler ammonia fume mixing device, the relative standard deviation of the ammonia mass concentration distribution above the inlet surface of the first catalyst layer in the reactor was optimized from 12.9% to 5.3%. This paper can provide a valuable reference with practical implications for subsequent research. [ABSTRACT FROM AUTHOR]

Supercritical boilers have become a major development trend in coal-fired power plants, and the air distribution strategy is a key factor in the design and operation of making it fully combustible. In this paper, the mathematical and physical models of a 350 MW supercritical boiler is established, and the optimal air distribution mode of the boiler at different load is determined based on the furnace outlet temperature, NOx concentration, and O2 content. The air distribution control strategies were derived and the corresponding procedures were established. 160 MW and 280 MW were selected for positive pagoda and 180 MW and 230 MW for waist reduced. At 290–350 MW load, the effect of adjusting the combustion damper opening on the outlet oxygen is weak, so preferentially adjusting the SOFA damper opening can achieve better results. The results show good thermal efficiency and emission performance and are applicable to adjust the air distribution mode to achieve fuller combustion of supercritical boilers. [ABSTRACT FROM AUTHOR]

Sustainability in construction is related to the use of industrial by-products, such as fly ash (FA). FA varies in chemical/mineralogical composition, depending on the raw materials burnt during its production. While FA produced from coal-fired power stations is extensively used in cementitious composites, heavy oil FA produced from the firing of heavy fuels (e.g., mazut or diesel) remains largely unused. This paper focuses on the novel use of heavy fuel fly ash (HFFA), as a replacement of Class F FA, in high-volume fly ash self-compacting composites. Two different grain size distributions of HFFA were used in quantities 5–15% w/w of cement and Class F FA for the production of the composites. The assessment of the physico-mechanical properties and microstructure of the end-products at different curing ages suggests that HFFA may be used at quantities ≤10% w/w, without any negative effects. In fact, depending on the quantity and grain size distribution of the HFFA, this may even improve some of the properties of the end-products in the long term, provided that a careful mix design is adopted. The findings show the potential of sustainable reuse of HFFA and are beneficial for its incorporation into design codes. [ABSTRACT FROM AUTHOR]

In this paper, the research progress of ammonium bisulfate (ABS) volatilization in coal-fired power plants the SCR denitrification process was reviewed. Combination with self-made experiments, SEM, flue gas analyzer and TG-DTG curves of ABS and ion chromatography. The volatilization and condensation characteristics of ABS were investigated carefully. Results show that as the temperature increased by 50 oC, the ABS/AS volatilization rate increased by an order of magnitude. The decomposition process of ABS should have a two-step reaction. The reaction in the initial volatiliza-tion stage is ABS dehydration turned into (NH4)2S2O7. The reaction in the rapid volat-ilization stage is (NH4)2S2O7 decomposed into NH3, N2, SO2 and H2O. There is an inter-section in the reaction temperature range (especially 300 oC) between the two-step re-action. This research provides an experimental basis for temperature control of ABS to avoid air pre-heater fouling. [ABSTRACT FROM AUTHOR]

As part of the European Green Deal-aligned net-zero push by 2050, the EU was striving to transition its energy sector to using mostly renewables. Natural gas, however, remained a crucial transition fuel to replace high GHG emitting coal-fired power. But gas prices have been on the rise following the COVID 19 pandemic and have further been exacerbated following Russia's invasion of an EU gas transit country, Ukraine. Since EU's largest economies rely on Russian gas, some countries have already turned retired coal-fired power plants back online, used them in reserve, or delayed their scheduled decommissioning to meet increasing energy demands, which in itself has pushed the EU further away from its previously set climate friendly goals. On the other hand, if Russia were to cut off its gas supply to the EU completely, the EU might be seen massively installing renewables and heat pumps and go through the energy transition faster than it initially planned for. That is why the aim of this paper is to analyze and discuss both scenarios, their short and long-term implications, and the resulting effects on the EU's energy policies. The end result will consist of the pros and cons of each scenario and will trace out both the most beneficial as well as the most likely policy steps of the EU's energy community in response to the energy crisis brought by the War in Ukraine. [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]

Aiming at the problems of secondary pollution and resource waste caused by inaccurate input of coal and ammonia in coal‐fired power plant, an optimal controlling method of combustion and denitration coordinated operation based on Deep Deterministic Policy Gradient (DDPG) is proposed in this paper. First, the environmental model is constructed by the Stacking algorithm to predict the NOx emission concentration of the combustion and denitration system, which provides environmental state feedback for the optimal controlling model. Second, the optimization controlling model is constructed based on the DDPG algorithm within the standard limitation of denitration efficiency and NOx emission concentration. This model takes the minimization of comprehensive cost as its optimization objective to realize the optimal control of controllable variables in the cooperative operation process of combustion and denitration. The experimental results of real operational data from 1000 MW boiler unit in a power plant locating in south China show that the optimization results of coordinated operation for the combustion and denitration system are better than single‐stage optimization results. In addition, the total cost is reduced by 1%–3% on average compared with before optimization. [ABSTRACT FROM AUTHOR]

This paper is effectively a scenario analysis of the energy system of Bosnia and Herzegovina (BiH) from the perspective of the possible future reduction of greenhouse gas (GHG) emissions in the power generation sector, with the aim to become climate neutral by 2050, in compliance with the Green Agenda for the Western Balkan. According to the data from 2016, the share of power generation in the total GHG emissions in BiH was approximately 50%. By using the LEAP (Long-range Energy Alternatives Planning) energy model, two scenarios—the "gradual transition scenario" and the "climate neutral" scenario—have been analyzed for the period 2018–2050, and each scenario included decarbonization measures such as the extensive use of Renewable Energy Sources (RES). Unlike the climate neutral scenario, the gradual transition scenario includes the replacement of certain parts of the old, currently-in-operation Coal-fired Power Plants (CFPPs) with the new CFPP, which is more efficient. In the climate-neutral scenario, that part of the existing CFPPs is replaced by a mix of RESs. The results from the first scenario suggest that the share of CFPPs in electricity generation has gradually decreased from 69.3% to 16.3% in 2050, and CO2 emissions from the power generation sector in 2050 will be 2.2 million tons—roughly 83.5% less than in 2014. According to the second scenario, the emphasis is strongly on the growth and promotion of RESs, which have significantly taken over the roles of major producers of electricity, encouraging the low-carbon development of BiH. Analysis results show that, in 2050, there will be no CO2 emissions from power generation. It can be concluded that specifically designed energy models for the optimization of capacities and CO2 emissions through convergence towards RESs could be an optimistic and promising option for BiH to become climate neutral while meeting increasing energy demands. The results show the required RES capacities needed for achieving climate-neutral power generation by 2050, with the current rate level of power generation. Based on the results, RES investment needs can be estimated. Overall, the results of the scenarios can be used for the strategic planning of the power generation sector in BiH until 2050. [ABSTRACT FROM AUTHOR]

Coal-fired power industry is under enormous pressure to accomplish carbon emission reduction targets. This paper proposes a bi-level multi-objective model for co-firing biomass with coal under carbon cap-and-trade regulation which considers a leader-follower Stackelberg game between the authority and the coal-fired power plants. The upper level regards social welfare maximization and allocation satisfaction maximization as its multiple objectives, while the lower level attempts to maximize the profits of each coal-fired power plant. The inherent uncertainty prompts the motivation for employing fuzzy set theory to characterize the uncertain parameters and determine their exact values. A case study from Shandong Province, China is provided to demonstrate the practicality and efficiency of the optimization model. ε -constraint method and interactive algorithm are used to solve the model, and furthermore the solutions associated with different free carbon emission quota levels and minimal allocation satisfactions have been generated to examine the influences. Based on the analysis and discussion, the methodology can meet the carbon emission reduction goals and transit to a lower-carbon power generation. It also assists the decision makers to develop desired quota allocation strategy in accordance with their attitudes and actual conditions. [ABSTRACT FROM AUTHOR]

Torrefied wood (TW) may offer the opportunity to generate relatively large amounts of renewable energy in existing coal-fired units. To test this, several blends of pelletized TW were successfully cofired with coal at percentages up to 100% TW in a 49-MW coal-fired unit at a power plant in the southeastern United States. \mboxNO\mathrm{x} and sulfur emissions were significantly reduced with increased TW. Boiler efficiency was reduced slightly due to high TW fuel moisture at testing. Issues with dust suppression and fuel pile self-ignition were successfully addressed. This paper presents the details of the testing and results. [ABSTRACT FROM AUTHOR]

This paper presents a systematic approach to study the dominant electromechanical oscillatory modes in a large-scale coal-fired thermal power plant. The proposed methodology first involves analysing the fault recorder data. Next a detailed linearized model is developed, and the oscillatory modes are identified via the eigenvalue analysis. Computations of the participation factors and mode shapes are useful in identifying the contributing sources on the oscillatory modes and their types. The importance of verifying the accuracy of the dynamic data used in the simulation environment for practical power systems and validation of the linear model with nonlinear simulation are highlighted in the paper. The proposed methodology is applied to a 900 MW coal-fired real power plant in Sri Lanka power system. A dominant oscillatory mode of frequency 1.2 Hz where the coal power plant oscillates against the network is identified using the proposed methodology. This systematic approach can be applied to any real power system including renewable energy sources using correct dynamic models. [ABSTRACT FROM AUTHOR]

The acceleration of distributed energy resources and carbon pricing policies have compelled utilities to act and to prioritize carbon-constrained infrastructure augmentation in their capital programs. To implement various carbon emission reduction policies, power system transmission planning has become more challenging. The existing energy system will face massive retirement of coal-fired power plants (CFPPs), large scale integration of renewable energy and network expansion. In this paper, an electricity network planning and transformation roadmap, which has two milestones, is put forward. In the first stage, a mathematical model is proposed based on the average cost of carbon emission reduction to realize the cooperation of CFPPs retirement and renewable energy investment. It can help the network carry out the transition from a fossil-fuel dominated system to a low-carbon oriented system. Because of the promising prospect of power-to-gas (P2G) technology, in the second milestone, a method based on carbon emission flow (CEF) is employed to help the power-to-gas stations (P2GSes) to select the construction site and capacity. The gas network constraints are modeled to guarantee that P2GSes can work smoothly without energy flow congestion in both electricity and gas networks. According to the simulation results in case studies, our method can reach the emission reduction target more economically and effectively, and the P2GSes can produce and absorb clean energy. [ABSTRACT FROM AUTHOR]

Due to the restriction such as the Minamata Convention as well as the IED of the European Commission, mercury removal from flue gases of coal-fired power plants (CPP) is an increasingly important environmental issue. This makes this topic very crucial for both the energy industry and scientists. This paper shows how mercury arises from natural resources, i.e., coals, through their combustion processes in CPP and considers the issue of mercury content in flue gases and solid-state coal combustion by-products. The main part of this paper presents a review of the solid sorbents available for elemental mercury control and removal processes, tested on a laboratory scale. The described solutions have a potential for wider usage in exhaust gas treatment processes in the energy production sector. These solutions represent the latest developments in the field of elemental mercury removal from gases. The authors present an overview of the wide range of solid sorbents and their modifications intended to increase affinity for Hg0. Among the presented sorbents are the well-known activated carbon solutions but also novel modifications to these and other innovative sorbent proposals based on, e.g., zeolites, biochars, other carbon-based materials, metal-organic frameworks. The paper presents a wide range of characteristics of the described sorbents, as well as the conditions for the Hg0 removal experiments summarizing the compendium of novel solid sorbent solutions dedicated to the removal of elemental mercury from gases. [ABSTRACT FROM AUTHOR]

The implementation of climate change policy in South Africa inevitably requires decision-makers to navigate issues of development. This paper explores some of the implications of this requirement by examining the case of a proposed new independent coal-fired power producing plant, Khanyisa, in the province of Mpumalanga from the perspective of complexity studies, an emerging transdisciplinary field. Complexity thinking re-casts the Khanyisa project in a whole-system view, encouraging an active consideration of scale, perspectives, different knowledges, and cumulative impacts. In so doing, tensions both between and within dimensions of climate mitigation and development are quickly revealed, a complexity which is theorised in complexity studies as the raw material for systemic transformation. This wholesystem conceptualisation also undermines incremental and relative arguments that Khanyisa mitigates greenhouse gas emissions. Further, the complex systemic property of non-linearity suggests that the Khanyisa decision is more significant than its power generation capacity indicates. Attention to the conceptual simplification inherent in 'development' highlights what is lost through such simplification, as well as what is gained, and by whom. Finally, complexity thinking foregrounds the multiple scales at which the systemic climate mitigation and development implications of Khanyisa play out. Currently there is very little policy-making capacity nationally, regionally or in eMalahleni to look at alternatives, or 'spaces of possibility' through the complexity lens for both development and climate mitigation. This case argues that new policy processes are needed, which go far beyond policy and regulatory processes steeped in path dependencies and incrementalism. [ABSTRACT FROM AUTHOR]

The paper presents the researches undertaken for the superior capitalization, in the context of the circular economy, of the power plant ashes and other industrial wastes, in the construction materials industry. Taking into account the specific properties of the ash from the thermal power plant, a technological scheme was elaborated through which the recovery of iron oxides was pursued (their share being significant). Due to the hydraulic properties of power plant ash, similar to those of classical construction materials, laboratory research was conducted in order to develop a material usable in the construction materials industry with superior characteristics. [ABSTRACT FROM AUTHOR]

In this paper, an application of linear programming in optimizing the procurement and movement of coal for an Indian coal-fired thermal power-generating company is presented. Results show that there is immense potential not only for significant cost savings but also for reduced logistics between different coal source-power plant pairs. The target plant load factor at each power plant can be achieved without the need of any imported coal which would not only save precious foreign exchange, but also reduce the logistics involved in the import of coal and transport to power plants. Sensitivity analyses have also been performed with varying coal supply and coal quality levels. The issue of greenhouse gas (GHG) emissions from coal-fired power plants has also been addressed. The trade-off between the optimal total cost and GHG emission targets has been explored. Results show that it is possible to significantly reduce carbon footprints with a marginal increase in the optimal total cost and without the need of import of coal. However, if it is desired to further reduce GHG emission targets, optimal total costs rise substantially with imported coal gradually substituting domestic coal. It is believed that the results presented in this paper would provide a fresh perspective with regard to the allocation and movement of coal. Finally, recommendations and concluding remarks are presented. [ABSTRACT FROM AUTHOR]

Relying on coal as primary fuel in thermal power plants represents an unsustainable concept due to limited coal reserves and a negative environmental impact. Efficient utilization of coal reserves and a request for minimization of irreversibilities are imperative for thermal power plants operation. Numerous studies have shown that a steam boiler is a thermal power plant component with the highest irreversibility. The idea of this paper is to quantify the amounts and sources of irreversibilities within a steam boiler and its components, serving a 348.5MWe thermal power plant. Having this in mind, exergy and exergoeconomic analysis of a steam boiler is presented in this paper. Exergy destruction and exergy efficiency of all boiler components and of the boiler as a whole were calculated. Based on exergy flows and economic parameters (cost of the boiler, annual operation hours of the unit, maintenance factor, interest rate, operating period of the boiler), exergy analysis resulted in the cost of produced steam. The obtained results show that the boiler exergy efficiency is at 47.4%, with the largest exergy destruction occurring in the combustion chamber with a value of 288.07 MW (60.04%), and the smallest in the air heater with a value of 4.57 MW (0.95%). The cost of produced steam is calculated at 49,356.7 $/h by applying exergoeconomic analysis. [ABSTRACT FROM AUTHOR]

The subcritical coal-fired boilers of thermal power plants consist of a combustion chamber, economizer unit, drum unit (drum, riser, and downcomer), superheater unit (primary superheater, secondary superheater, and final superheater), and reheater unit. The input and output of these units are highly interactive in nature. The efficiency of the subcritical plants is only around 33%. The efficiency needs to be increased to produce more power for the increasing demand, which can be achieved only by implementing supercritical technology or ultra-supercritical technology. However, the conversion of existing subcritical power plants to supercritical power plants is impossible due to the installation cost. So in order to increase the overall efficiency of the existing subcritical power plants, boilers of such units must be examined in order to find safer operational practices. This paper highlights the mathematical modeling of the economizer unit and drum unit of boiler, which can help in enhancing the performance of the boiler system of the power plant. Mass and energy balances for the integrating boiler units have been formulated using first principle laws. The developed model has then been validated with actual plant data obtained from a 210 MW coal-fired thermal power plant. The performance of the open loop responses of the model are analyzed and are included in the results and discussion of the paper. The model provides support for level, pressure, and temperature measurements and predictions. The effect of changes in the parameters of the boiler are studied and discussed in detail [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]

The denitrification process was completed in coal-fired power plants, resulting in the fly ash containing NH4HSO4. When this kind of fly ash with ammonia was applied to cement and concrete, there could be phenomena such as a retarded setting time, decreased compressive strength, and volume expansion. This paper mainly investigated the influence of fly ash containing NH4HSO4 on the properties of fly ash cement paste, and pastes with NaHSO4 were set as the control samples. The research on Na+ in cement hydration was studied. The influence of NH4HSO4 content in fly ash on the properties of fly ash cement paste was also investigated. It was found that NH4+ could greatly affect the properties of fly ash cement paste, such as significantly reducing the fluidity, prolonging the setting time, decreasing the compressive strength, increasing the drying shrinkage, decreasing the total heat released during the hydration, and affecting the content of calcium hydroxide hydrate. Increasing the ammonia content of the denitrified fly ash would reduce fluidity, retard its setting time, increase the porosity of the cement stone, and increase the number of pores with large sizes in the fly ash cement paste. The increase of porosity and pores with large sizes in cement decreases the compressive strength and increases the drying shrinkage of the fly ash cement paste. [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]

The platen superheater boiler tubes of a 660 MW coal-fired power plant have failed after long term in service. The failed boiler tubes are made of ASME SA-213 T12 and ASME SA-213 T22 and both have the same outer diameter of 50.8 mm and minimum wall thickness of 5.156 mm and 8.509 mm, respectively. The operating pressure of the platen superheater tubes is 178–179 barg, while the operating temperatures are 379–390 °C (inlet) and 430–440 °C (outlet). The failed tubes experienced severe localized thinning or erosion on the outer surface and occurred at different locations. The types and factors that cause erosion in the platen superheater tubes are discussed in this paper. The metallurgical assessment was carried out by preparing several specimens from the failed platen superheater tubes. Various laboratory tests were carried out, including visual and macroscopic examination, chemical analysis, metallographic examination, hardness and tensile testing, and scanning electron microscopy equipped with energy dispersive spectroscopy analysis. The results of the metallurgical assessment obtained show that the platen superheater tubes have experienced localized fireside erosion and leaks in several locations of the tubes. Formation of this localized fireside erosion is most likely caused by improper use and/or malfunction of the soot blower applied in the boiler. In addition, tube leaks due to localized fireside erosion may have also caused by erosion due to steam cutting from the adjacent tube that previously ruptured due to severe soot blower erosion. Besides, several platen superheater tubes have also experienced formation of hard and thick ash or slag deposits on the outer surfaces where no fireside erosion or leaks occurred. However, formation of these deposits was found to be insignificant to the fireside corrosion on the platen superheater tubes. [ABSTRACT FROM AUTHOR]

Oxidation denitration is one of the most efficient ways to remove NOx from flue gas in a coal-fired power plant. However, this oxidation denitration produces saline solution containing a high concentration of nitrate, which needs to be well treated. In this paper, MFC was firstly used to treat the high nitrate content saline denitration solution from ozone oxidation denitration of a coal-fired power plant. The influences of chemical oxygen demand (COD) and initial nitrate concentration on the nitrate removal and electricity generation of MFC were investigated by sequencing batch mode. The results showed that using MFCs could efficiently remove nitrate from coal-fired power plant saline denitration solution with nitrate nitrogen (NO3−-N) concentration up to 1510 mg/L. The average nitrate nitrogen removal rate was as high as 248.3 mg/(L·h) at initial nitrate nitrogen concentration of 745 mg/L and COD concentration of 6.5 g/L, which was eight times as high as that of the conventional biological method. Furthermore, the MFC required an average COD consumption of 3.42 g/g-NO3−-N which was lower than most of the conventional biological methods. In addition, MFC could produce a maximum power density of 241.1 mW/m2 while treating this saline denitration solution. [ABSTRACT FROM AUTHOR]

South Africa is one of the most carbon-intensive economies in the world, but it is presently experiencing an energy crisis, as its utility company cannot meet the country's energy demands. The use of renewable energy sources and retiring of coal-fired power stations are two important ways of alleviating this problem, as well as decarbonizing the grid. Repurposing retiring coal-fired power stations for renewable energy generation (RCP-RES) while maintaining energy sustainability and reliability has rarely been researched. This paper proposes macro- and microelements for repurposing retiring coal-fired power stations for renewable energy generation in Camden with the aim of improving power generation through a low-carbon system. In this model, concentrated solar power (CSP) and solar photovoltaics (SPV), in combination with storage technologies (STs), were employed for RCP-RES, owing to their excellent levels of availability in the retiring fleet regions. The simulation results show that the power densities of CSP and SPV are significantly lower compared with retiring a coal-fired power plant (CFPP). Both are only able to generate 8.4% and 3.84% rated capacity of the retired CFPP, respectively. From an economic perspective, the levelized cost of electricity (LCOE) analysis indicates that CSP is significantly cheaper than coal technology, and even cheaper when considering SPV with a storage system. [ABSTRACT FROM AUTHOR]

In this paper, a thermodynamic analysis of coal-fired thermal power plant is done at a particular inlet temperature (507.78 °C) and at different inlet pressures (122.16 bar, 123.14 bar, 124.12 bar, 125.10 bar, 126.08 bar, 127.06 bar and 128.04 bar). And then, correction factor curves for power and heat rate are generated for combined effect of inlet temperature/inlet pressures. These curves indicate that if inlet temperature and inlet pressure of steam (which is produced in boiler) vary, then power output and heat rate also vary. So these generated curves are used to prove that the designed/installed power plant is correct. Variations in the power/heat rate outputs occur because inlet conditions are not as per the designed conditions. These curves also help to identify the conditions at which the performance of the power plant is best. The paper concludes that 120 MW thermal power plant gives maximum power at 128.04 bar inlet pressure, whereas minimum heat rate can be achieved at 125.10 bar inlet pressure which is the designed pressure. [ABSTRACT FROM AUTHOR]

This study focusses on the effect of milling of fly ash obtained from four different sources on the properties of high volume fly ash (HVFA) mortar. Two fly ash samples with low loss-on-ignition (LOI) were taken from a coal-fired power plant, while the other two with high LOIs were obtained from a textile factory and from a paper mill, respectively. Milling was performed using a rod mill at a certain period of time. The workability of HVFA mortar with constant water to cementitious ratio was controlled by adjusting the superplasticizer content. The results show that the specific gravity of fly ash increases after milling. Utilizing milled fly ash ends up with significant strength increase of HVFA mortar, especially those utilizing high LOI fly ash. This shows that milling is an excellent fly ash beneficiation technique, especially on the one with high LOI value. [ABSTRACT FROM AUTHOR]

Limestone flour is used in a variety of industrial sectors such as power and heat generation, glass-making, paper-making, the construction industry and construction materials manufacturing, the production of agriculture, plastics and rubber goods, as well as coal mining, and environmental protection. This paper aims to characterize and interpret the limestone flour supply and demand trends in the main applications in Poland in the last decade. In order to track the changes of domestic consumption for this commodity, its major users have been surveyed along with analyses of data from the Statistics Poland (GUS). The results showed that during 2009–2018 the coal-fired power plants became the biggest customer of limestone flour utilized as a sorbent in the wet flue gas desulfurization method (FGD). This method has been implemented in the vast majority of Polish power plants. It is estimated that in the last decade the total annual production capacity of limestone flour at the milling plants in Poland increased by 1.5 million tons, to around 6.0 million tons. In the forthcoming years, this is expected to continue to increase despite EU restrictions on fossil fuel use (especially hard coal and lignite). Other promising areas of future growth are: for limestone flour of medium quality—the construction materials manufacturing and the construction industry itself, for limestone flour of the highest quality—the glass industry, while for fine-grained limestone flour of high-quality—the plastics and rubber industries. In terms of resource security, it is worth noting that Poland is a country rich in limestone deposits. However, only some of them, that is, limestone rock varieties of the Jurassic and Devonian ages from the Kielce vicinity in central Poland are suitable for the production of high-quality limestone flour for the needs of the mentioned industries. The paper analyses the potential of the limestone flour production from the available limestone rock deposits with respect to the current and future needs of the domestic market in Poland. [ABSTRACT FROM AUTHOR]

To address the 2-degree target, rapid decarbonization for China's power sector would be essential in the coming decades. This paper attempts to assess the impact of early and delayed mitigation efforts for China's power sector with the application of China TIMES model. With the introduction of carbon budget, CO2 mitigation pathways and corresponding energy transition routes have been generated through scenario runs, then mitigation potential and key challenges of the power sector have been analyzed. The key findings are the following: (1) in both early and delayed 2-degree scenarios, the power sector is expected to achieve negative emissions by mid-century, and over 60% of cumulative CO2 mitigation is required comparing with current policies scenario; (2) in addition to the promotion of new and renewable energy, rapid phase-out of coal-fired power plants and the deployment of biomass CCS technology would also be essential to achieve the 2-degree target; (3) recent investment in new coal-fired plants could cause carbon lock-in in the long term, over 1000 GW of plants may be early retired during 2030–2050, leading to great economic losses; (4) the deployment of biomass CCS technology plays a vital role in meeting the severe mitigation challenge, in early and delayed 2-degree scenarios, a total of 9.9 and 11.7 Gt of negative emissions could be achieved respectively from 2010 to 2050. [ABSTRACT FROM AUTHOR]

Emulsified asphalt mixture has the characteristics of convenient construction and durable performance, but its poor early strength and demulsification seriously restrict the popularization and application of this material. At present, the coal gangue produced by coal-fired power plants is generally discarded, resulting in serious environmental pollution. The combination of coal gangue and emulsified asphalt can explore an efficient utilization way for more and more coal gangue and also solve the curing problem of asphalt. In order to give full play to the advantages of existing materials and make rational use of resources, this paper studies the factors affecting the performance of coal gangue emulsified asphalt mixture based on orthogonal experimental design and optimizes its material composition parameters by considering the coupling effect of two factors. The water stability of coal gangue emulsified asphalt mixture is evaluated by the immersion Marshall test. Finally, the strength formation mechanism of coal gangue emulsified asphalt mixture is analyzed from the microscopic point of view. The results determined 7.5% as the optimum amount of emulsified asphalt in coal gangue emulsified asphalt mixture and recommended the best parameter combination of 7.5% emulsified asphalt, 6% coal gangue, and 5% water consumption. With the increase of coal gangue content, the water loss resistance of emulsified asphalt mixture increases gradually, and the water stability of emulsified asphalt mixture can be improved by adding coal gangue. According to the microscopic analysis, the strength of the mixture is formed by the joint action of emulsified asphalt and coal gangue, in which the hydration products of coal gangue and asphalt play the role of cementation and strength together. The ordinary emulsified asphalt mortar mainly contains CaCO3, which mainly plays the role of physical filling. [ABSTRACT FROM AUTHOR]

As the renewable energy fluctuating in the power grid, the traditional coal-fired power plant needs to operate on the extremely low load, so as to increase the share of renewable energy. This paper deals with thermodynamic simulation and exergy analysis of the coal-fired power plant integrated with the molten-salt energy storage system to explore the potential of reducing the minimum operation load. A steady-state simulation was performed to obtain the thermodynamic properties of process streams in a subcritical 600 MW unit. The results indicated that with simple main steam and re-heat steam energy storage plan, the storage efficiencies are 39.4-42.9% and 51.3-51.4%, the minimum operation load would decrease by 27.2 MW, 10.6 MW, respectively. Exergy analysis shows that the exergy loss mainly comes from the throttling process and temperature difference in the phase- changer heat transfer process. With optimized Molten-salt energy storage plans, the storage efficiencies increase to 72.6% and 78% via lead the exhaust drains or steam into higher pressure points; the minimum operation load decreases by 35.1 MW and 3 MW, respectively. Moreover, with the coupled plan including both optimized main steam and re-heat steam energy storage system, the minimum operation load would decrease by 80.7 MW, and storage efficiency is 75.1%. [ABSTRACT FROM AUTHOR]

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