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The development of a variety of methods by sequencing on economic planning and optimization can be realized by emphasizing collaborative, multi-purpose aspects, as well as increasing the variety of solutions that are environmentally friendly, make cost savings, and focus on using low carbon in this approach, use Generation Expansion Planning (GEP), which is the center for reducing the amount of carbon through the calculation process for the development of conventional power plants. In this study modeled the efficiency of Generation Expansion Planning (GEP). In this paper uses the planning method for socio cultural. This research focuses on making energy in a more flexible way. GEP can be a source of renewable energy solutions. In this literature focus on various methods for planning generation expansion through the GEP approach, in terms of finding the total investment and operating costs. This approach provides various guidelines for conducting new research projects. This model has various technicalities in increasing the efficiency of power plants for planning power generation expansion. [ABSTRACT FROM AUTHOR]

The system energy balance isn't always appropriate for detecting system flaws. Increasing the efficiency of individual systems of the plants would make a considerable difference. Numerous scholars have examined a systematic literature review of electricity, exergy, exergy-economic, and economic study of thermal power plants over the years. In this study, a significant amount of work has been done in fossil fuel power plants on the thermodynamic study of the Rankine period of subcritical, supercritical, and ultra-supercritical fossil fueled fired power plants. Further, energy, exergy and economic analysis of these three power plants of different capacities were clearly examined. This paper is intended for researchers who are working on 3-E analysis in a variety of coal-fired power plants. The scope of future research in coal-fired power plants is also indicated in this study. [ABSTRACT FROM AUTHOR]

This paper proposes using Big Data and Similarity Based-Modelling (SBM) to identify early alert in online monitoring of Paiton Coal-Fired Power Plant operating system. Similarity-based modeling is a nonparametric modeling technique that uses the similarity of a query vector with exemplar vectors to infer the model’s response. Big Data and SBM has been successfully used for anomaly detection on industrial applications. This method use historical operational data that has been filtered to eliminate outlier data/bad data. That filtered data become predicted data. After that, come actual data from Site and it will be compare with predicted data using SBM Method to search the condition of predicted data that almost the same with the actual data. If there are difference and at a certain time range, it will show the Early Alert. Early Alert is the indication of disturbance and has five (5) priority. The higher indication of disturbance, the priority also higher. With this method, Forced Outage can be reduced so that Power Plant’s Reliability can be good. [ABSTRACT FROM AUTHOR]

Nowadays, environmental problems are getting more and more serious. People pay attention to exhaust emissions, and the environmental pollution caused by automobile exhausts ignores the environmental cost caused by occupied land. Therefore, this paper builds a benefit-cost model (BCM) based on environmental costs. Using this model, we can analyze the cost and benefits of land use development projects and assess the feasibility of the project. First, the comprehensive weighting method (AHP and EWM) is used to screen the measurement indicators of ecosystem services. Then use Grey Correlation Analysis (GCA) to find some construction behaviors that have a greater impact on selected indicators. Finally, we use different methods to calculate environmental costs for different types of pollution. [ABSTRACT FROM AUTHOR]

Power plants become critical facilities that need to run every time without failure. The component in the power plant system has been equipped with sensors. These sensors will monitor the element's condition by periodically sending the related metric data to the control room or storing it for later evaluation. These sensor data can be analyzed for early anomaly detection on power plants. Traditional methods still need humans as experts to detect these anomalies; hence, human error is a factor. Using deep learning, we can take advantage of abundant data to learn the usual pattern and detect anomalies in future data. Many deep learning algorithms have been implemented in this case. However, the selection of these algorithms depends on the data's characteristics. This paper aims to provide a comprehensive, structured analysis of the data features and the algorithm used to detect anomalies in the data. Twenty-two recent power plant anomaly detection studies were compiled as a systematic review. This review will discuss power plant sensor data characteristics that need to be considered, such as raw data format, label usage, data dependence, and detection results. This review also discusses methods used to process unsupervised data, the relation of the multivariate data, and anomaly detection. This review aims to ease the selection of the appropriate anomaly detection algorithm for future research by considering the data characteristics. [ABSTRACT FROM AUTHOR]

The problem of selecting the optimal composition of operating units in power plants when planning short-term modes of power systems is a complex problem of nonlinear programming. Its solution usually boils down to determining the starting or stopping units in power plants for each interval of the planning period. Despite the current existence of many methods and algorithms for solving this problem, the issues of their improvement in the direction of increasing the accuracy of calculations and the reliability of convergence of iterative process, taking into account the new conditions of the functioning of power systems, as well as the capabilities of modern computing facilities, remains as an important task. In this paper, we propose a new algorithm for the selection of the composition of operating units in power plants based on a genetic algorithm, which, to a certain extent, meets modern requirements. The solution to the problem is carried out in two stages. At the first stage, generalized energy characteristics of the plants participating in the optimization are constructed. At the second stage, based on optimal coverage of the power system load schedule by all plants according to their obtained generalized energy characteristics taking into account all limiting factors, by the genetic algorithm, the optimal compositions of the operating units are determined. High accuracy of the result is ensured by the direct use of energy characteristics of plants, usually set in a tabular form, and the ability of the genetic algorithm to solve multi-extreme problems without any simplifications. The results of computational experiments, which confirm the high efficiency of the proposed algorithm, are presented. [ABSTRACT FROM AUTHOR]

Power Plant site selection is a structured process developed to identify and acquire suitable lands at an intended area or zone for future power plant development. The process includes, among others, the establishment of mandatory and rejection criteria as well as various site selection assessment parameters with the intention to develop the various attributes that significantly influence the suitability of a site for future power plant development. A workshop was therefore held to establish the criteria as well as parameters for the power plant site selection study. These criteria and parameters later become the principal guideline to identify potential sites for power plant development. This paper will however, only focus on the potential land-use zoning assessment parameter established during the workshop to evaluate and acquire suitable lands for future power plant development. [ABSTRACT FROM AUTHOR]

In order to meet the need for cleaner energy in the Green House Gas (GHG) emission reduction framework, the implementation of biomass cofiring in the coal-fired power plant (CFPP) is important. Cofiring of biomass and coal in CFPP is considered an alternative solution to answer the GHG emission problems and extend the life of power plants. Due to different characteristics of biomass compared to coal, however, the implementation of biomass cofiring in CFPP has faced many technical obstacles. It can increase the risk of slagging-fouling and corrosion due to the mineral ash and chlorine contents. This paper presents experimental investigations on the cofiring of palm oil waste with pulverized coal using a drop tube furnace. The characteristics of the composition of the ash particles were analyzed, Ash Fusion temperature (AFT), probe observation from DTF, also analyzed using scanning electron microscopy with energy dispersive X-ray (SEM-EDX). The experiment results show that cofiring palm oil waste with coal during combustion affects ash due to various physical and chemical properties. Cofiring coal with 25% of the biomass, either with an empty fruit bunch or oil palm frond, increases the slagging observed from the probe's deposits. The addition of 25% biomass, a blend of EFB and frond with a composition of 50% each, is better from the slagging aspect than single biomass. Further research is required to investigate the effect of different biomass proportions by weight, fouling's risk, and additives' use to mitigate slagging risk. [ABSTRACT FROM AUTHOR]

The use of biomass through co-combustion technology in industry and coal-fired power plants (CFPP) is being tested intensively. Biomass can replace 5-10% of coal capacity in CFPP and results in massive demand for biomass supply availability. Biomass from agricultural residues has excellent energy potential, with a theoretically convertible biomass energy value of 682,771 GW. However, the difference between agricultural residue biomass characteristics and coal causes a disadvantage in power generation, such as power de-rating. The process of converting agricultural residue biomass into solid fuel with coal equivalent characteristics needs to be carried out so that substitution of coal to biomass or with co-combustion technology can be implemented. This paper discusses the potential of agricultural residue biomass and methods of converting agricultural residues biomass into solid fuels for co-combustion technology. From the results of this study, it was discussed that the conversion technology commonly used in agricultural residue biomass is torrefaction (either wet or dry torrefaction). To optimize the conversion process of agricultural residues biomass into coal equivalent solid fuel, it is suggested a combination of conversion technology (multi-process) to be applied and used for processing several types of biomass. [ABSTRACT FROM AUTHOR]

Nuclear power is an undisputedly clean source of energy. However, the Fukushima nuclear power plant accident serves as a reality check to most developed countries that have nuclear power plants to rethink their power strategy due to the huge environmental impact it has if accidents happen. With this scenario, coal will still be relevant in power industry for many years to come. However, getting good quality coal economically has become a challenge. Coal blending practice will help to achieve the objective of getting enough coal for the boiler with correct quality. Optimizing the coal combustion in power plant will improve its efficiency and lead to reduction of greenhouse gases in the flue gas. One of the main objective in the coal combustion research is to develop techniques that help power plant operators utilizes coal cleanly and efficiently. Coal combustion also associated with green house emission or pollutants. CO, CO2, NOx and SO2 are major gases emitted by coal combustion. The operators need to ensure the desired power output is achieved and at the same time, maintaining the strict emission standard at all time. This paper will discuss the pulverized coal combustion and process involved. Coal blending practice among the power plant also will be discussed and reviewed. Further discussion on coal combustion emission and optimization techniques will also be discussed. It can be said that coal blending practice and emission control techniques are essential in ensuring sustainable coal plant operation for years to come. [ABSTRACT FROM AUTHOR]

Structured glass-fiber catalysts (GFC) can be used to condition flue gases of coal-fired power plants with sulfur trioxide in order to improve the capture of fly ash by electrostatic precipitators. Sulfur trioxide can be obtained by oxidizing sulfur dioxide, which is contained directly in the flue gas stream. The article is dedicated to the study of the kinetics of the oxidation of sulfur dioxide on Pt-based glass fiber catalysts. The paper discusses the effect of the concentration of sulfur dioxide and oxygen on the kinetics of the reaction. [ABSTRACT FROM AUTHOR]

In coal-fired power plants, the performance of the pulverizer is very influential on the overall performance of the power plant (heat rate). Pulverizer is used to crush coal, so it is designed to supply the right size of coal for combustion in the boiler. to get the optimum performance and capacity of the pulverizer, the pulverizer must be used according to the design of the pulverizer taking into account the index Hardgrove Grindability Index (HGI), raw coal size and moisture content. On the other hand, pulverizer performance also requires primary airflow and good coal fineness size, which is used as transportation air and primary combustion air in the boiler. This paper presents an experimental study into the effects of classifier vane opening integrated with primary air-fuel ratio (1,7:1; 1,8:1; and 1,9:1) to fineness production passed 200 mesh. In this experimental, the effects of opening classifier vane settings and primary airflow to coal fineness particle size and coal flow in coal pipe distribution were measured by using dirty pitot air test dan isokinetic coal sampling. Five different position opening of classifier vane settings and three variations different of primary air-fuel ratio were the test and the effect of fineness particle size resulting from was noted and counted. During the test, the operational data of the plant is still considered, to determine the effect of the test results on the flue gas temperature from flue gas temperature, reheater, and superheater attemperator spray flow because related to the combustion of fineness. the test results show that the opening set of the classifier with a 45% opening with 1,8:1 primary air-fuel ratio. [ABSTRACT FROM AUTHOR]

During the low-load operation of the boiler side of the coal-fired power plant, the temperature of the SCR inlet flue gas is lowered, which can not meet the optimal reaction range of the denitration catalyst, and the catalyst reactivity is reduced. On the other hand, the baffle provided in the tail flue is non-adjustable. Under low load, the flow field in the flue is uneven, which leads to an increase in ammonia slippage. The ammonia escape detection instrument of some power plants is not accurate. The increase of ammonia slip increases the amount of ammonium bisulfate, which leads to blockage of air preheater and affects the operation of coal-fired units. Safety and economy. In this paper, the concrete measures of flow field transformation are proposed through the scheme of digital model and physical model. The experimental scheme is proved that the scheme is feasible under cold conditions and has good effects. [ABSTRACT FROM AUTHOR]

Coal-fired power plants are the largest contributor to electricity production in China, and much of China's total capacity in coal plants has been added within the last 10 years. However, the Chinese government has recently shifted from supporting the development of coal power plants to cancelling many proposed projects. In addition, government support of renewables, including solar, has increased dramatically. Combined with a stable or slowing national energy demand, China's energy generation capacity is outpacing need. Curtailment in China typically begins with coal, and as such, the capacity factors on coal-fired plants are decreasing. All indications are that this trend will continue and extend to other fossil-fuel based generation in the future. Many Rankine power cycles found in fossil-fuel based electricity generation operate at steam temperatures around 550°C, a temperature that can be matched by Concentrating Solar Power (CSP) technologies operating with molten salts. An advantage of installing CSP technology as a hybrid with existing plants is the complete utilization of existing power block equipment, including the turbine, cooling, and power transmission systems. In addition, direct molten salt thermal energy storage allows the solar portion of the plant to operate through transient events or, if desired, up to 24 hours a day. The steam turbine can operate consistently at full load, and therefore the highest efficiency, while still directly reducing fuel consumption or maintaining the low capacity factor of the coal boiler. There are other advantages, such as a potential increase in plant capacity factor if currently limited by governmental regulations on the quantity of fossil fuels used, or increased revenue if a power purchase agreement or carbon emission credit can be reached valuing the solar portion of plant generation higher than the fossil-fuel portion. This paper examines the current state of the Chinese energy market and the variables above are explored to determine the engineering challenges, economic feasibility, and potential market for CSP hybridization with existing coal-based plants in China. Example sites are identified and evaluated, risks and challenges are addressed, and the final Levelized Cost of Energy (LCOE) and power generation results are compared to current Chinese pricing for greenfield CSP projects. The LCOE calculations used do not include generation from the coal side of the plant. These projects are economically attractive, achievable with today's technology, and provide a market on the scale of gigawatts of installed CSP capacity. [ABSTRACT FROM AUTHOR]

In order to maintain the availability of electricity supply, a failure at the power plant is mandatory to be prevented. If damage has occurred, analysis of the root cause of failure must be prioritized to resolve the problem and prevent further damage. One of the important units in a power plant is a boiler that has a role as a steam generator producing the steam by changing the water in the liquid to the vapor phase. The quality of the (feed) water becomes one crucial factor in determining the lifetime of a boiler. Moreover, some factors related to the process variable control such as velocity, temperature, pressure, and flow rate of fluid should follow the specified design. Otherwise, the failure can occur, resulting in the unit shutting down, thus stopping the electric production. In this paper, the mechanism of the leakages that occurred at boiler bottom wall tubes of the steam power plant was investigated. Quality of (feed) water and several factors associated with the leakages such as temperature, pressure, and fluid characteristic are mainly considered the suspect contributing to the damage. Further to this, macro-and microstructural observations at the leaked tubes as the physical analysis were done. Analysis of chemical composition was performed to the (feed) water. Other factors concerned with the failure were also observed to validate the root cause analysis and mechanism of the leakages. Chemical analysis of (feed) water shows that the excess content of hydrazine (N2H4) as an inhibitor of corrosion is 100 times more than specified representing the low-quality level of (feed) water which significantly influences the aggressiveness of the water. In addition to this, an intentional turbulence of the flow rate of (feed) water shown by having a Reynold number of 33,000 together with the contaminated (feed) water significantly increases the risk of failure at the inner tube. Macro observation exhibits a sectional reduction on the upper curve radius at the leaked tubes indicating that a loss of product reaction between the outer tube surface with a suspicious variable occurred during the operation. Moreover, a damage to the protective magnetite layer was particularly found around the leakage denoting that a local failure happened at the inner surface tube. On the other hand, micro observation shows a local plastic deformation implying an increase of high local temperature around the leaked tubes. To conclude, the tube leakages are mainly resulted from the collaboration of suspicious factors originating from the ambient environment on both sides of the tubes. Indeed, the low level of water quality, the high turbulence of flow rate, and the increasing of local temperature during operation at inner tubes successfully caused the erosion corrosion. While the suspicious factor at outer tube, such as the fuel, led to induce the pitting corrosion. In this case, both corrosions are responsible factors to encourage the failure. [ABSTRACT FROM AUTHOR]

Fossil fuels are contributing the largest share in meeting up energy demands of urban lifestyle across the globe. May it be gasoline or coal, all sort of fossil fuels are drilled out of earth crust to burn on the earth surface creating huge burden on air quality. Incomplete combustion of fossil fuels cause pollution of carbon monoxide and other gases. It also eats away the breathable oxygen from atmosphere. Rampant use of coal in power sector causes above problems adding to the global warming phenomenon. Magnecules and magnehydrogen are seen to be best additives to fossil fuels which can effectively enhance the combustion efficiency of fossil fuels. Present paper discusses the enhancement in combustion efficiency of fossil fuels in terms of increased utility of carbon and improved quality of emission reducing the amount of obnoxious gases. [ABSTRACT FROM AUTHOR]

Utilizing CO2 capture and storage (CCS) technologies is a significant way to reduce carbon emissions from coal fired power plants. Cryogenic CO2 capture (CCC) is an innovative and promising CO2 capture technology, which has an apparent energy and environmental advantage compared to alternatives. A process of capturing CO2 from the flue gas of a coal-fired electrical power plant by cryogenically desublimating CO2 has been discussed and demonstrated theoretically. However, pressurizing the inlet flue gas to reduce the energy penalty for the cryogenic process will lead to a more complex system. In this paper, a modified CCC system utilizing a reverse Brayton Cycle is proposed, and the energy penalty of these two systems are compared theoretically. [ABSTRACT FROM AUTHOR]

In the process of natural gas transportation, cement production and coal-fired power, the gas-solid two-phase flow exists widely in pipelines. The existence of solid particles may cause the erosion of the pipeline, especially in the elbow of the pipeline. Equations used to predict erosion rate are usually obtained from well-controlled experimental tests for solid particles carried in a gas or liquid flow. The particle impact speed and impact angle affect the erosion process and are two major parameters in most erosion equations. In this paper, the erosion of 90° elbow was studied by using Computational Fluid Dynamics (CFD), Discrete Particle Model (DPM) and erosion equations. The maximum erosion rate and the erosion position were reported. Particle size does not influence the erosion rate when particle size is bigger than a certain degree. When the mass ratio of sand loading to fluid is less than 1, erosion ratio is proportional to the loading mass. The erosion rate is lower for larger radius elbow, and the erosion rate is greatly declined by using the plugged tee instead of an elbow. [ABSTRACT FROM AUTHOR]

Over ninety percent of Mongolia's energy load is run through the Central Energy System. This primary grid provides Mongolia's capital, Ulaanbaatar, with the power it uses to function. In the first half of 2010 the Central Energy System managed 1739.45 million kWhs, a 4.6 percent increase from 2009. If this growth rate continues, by 2015 Ulaanbaatar's three power plants will be unable to generate enough heat and electricity to meet the city's needs. Currently, plans have been proposed to rehabilitate the aging coal power plants. However, rising maintenance costs and growing emission levels make the long-term sustainability of this solution uncertain. The following paper analyzes the capital, maintenance, and decommissioning costs associated with the current rehabilitation plans and compares them with a nuclear alternative. [ABSTRACT FROM AUTHOR]

The main emphasis of this paper is on the engineering economics and design developments in the field of thermal power generation in Pakistan. Pakistan is rich with coal fields but is making no use of this available natural resource to fulfil its energy demands. The shortage of power is getting worst day by day and to align with the power requirements, Pakistan needs to add 2000 MW each year to national grid. With the increasing prices of natural gas and oil, Pakistan should consider coal, the abundantly available natural resource, as an alternate fuel for its new power plants to overcome the power crises. [ABSTRACT FROM AUTHOR]

In this paper, a preliminary study is performed on the application of Class-C fly ash based geopolymer as road base material. The Class-C fly ash as a base material is collected from Manjung Coal-Fired Power Station, Lumut, Perak Malaysia. Geopolymer was produced by the reaction of fly ash with an alkaline activator (a mixture of Na2SiO3 and NaOH solutions). The effects of various NaOH concentration and fly ash/alkaline activator ratio to the strength of geopolymer paste were studied. The concentration of NaOH used in this study was 8 M, 10 M and 12 M. Various ratios of fly ash/alkaline activator (1.0, 2.0 and 3.0) and a constant ratio of Na2SiO3/NaOH at 2.5 were studied to define the maximum compressive strength. Tests were carried out on 50 x 50 x 50 mm3 cube geopolymer specimens and the test was conducted on the day-7 and day-28 for all samples. Results revealed that the 10 M NaOH concentration with the fly ash/alkaline activator of 3.0 is deduced as the optimum ratio, which exhibited the highest compressive strength at day-28 of testing. [ABSTRACT FROM AUTHOR]

In Malaysia, coal is the largest fossil fuel used to generate power electricity which is 54.05%. By burning coal, greenhouse gas (GHG) emissions will continuously increase and affect global warming. Therefore, one of the alternatives is by promoting the co-firing coal and biomass in the existing coal-fired power plant in Malaysia. The past decade has seen an increase in the use of Computational Fluid Dynamic (CFD) to analyse the thermal performance of the coal-fired power plant. A coal-fired power plant for this study is referring to a 150MW subcritical boiler with tangential burner with the design pressure and temperature are 188 bar and 540 °C. This plant burned coal from Adaro and Hatillo. CFD simulation for co-firing is using 5% of sawdust at first level burners. From this study, several CFD methods were applied including the Eulerian-Langrangian approach to solve the two-phase gas-solid equation, Reynolds Averaged Navier Stokes (RANS) equation combined with k-ɛ Model to solve the turbulence problem in the gas phase, Discrete Ordinates Method (DO) to solve the radiative transfer equation (RTE) and Weighted Sum of Gray Gases Model (WSGGM) was used to calculate the absorption coefficient of the gas mixture. Based on the contour analysis result, found out that by co-firing coal and biomass, the burnout is reduced from an average of 0.45 kg/s to 0.33 kg/s when compared to pure coal combustion. This is mainly due to high volatile matters (VM) in the biomass. The concentration per unit thermal is also reduced to 42% when co-firing with sawdust. The early devolatilization will increase the gas and local temperature at each burner zone. The CO concentration was higher at the burner zone due to devolatilization. [ABSTRACT FROM AUTHOR]

Airborne particulates trace metals are considered as public health concern as it can enter human lungs through respiratory system. Generally, any substance that has been introduced to the atmosphere that can cause severe effects to living things and the environment is considered air pollution. Manjung, Perak is one of the development districts that is active with industrial activities. There are many industrial activities surrounding Manjung District area such as coal fired power plant, quarries and iron smelting which may contribute to the air pollution into the environment. This study was done to measure the concentrations of Hg, U, Th, K, Cu, Fe, Cr, Zn, As, Se, Pb and Cd in the Airborne Particulate Matter (APM) collected at nine locations in Manjung District area within 15 km radius towards three directions (North, North- East and South-East) in 5 km intervals. The samples were collected using mini volume air sampler with cellulose filter through total suspended particulate (TSP). The sampler was set up for eight hours with the flow rate of 5 L/min. The filter was weighed before and after sample collection using microbalance, to get the amount of APM and kept in desiccator before analyzing. The measurement was done using calibrated Energy Dispersive X-Ray Fluorescence (EDXRF) Spectrometer. The air particulate concentrations were found below the Malaysia Air Quality Guidelines for TSP (260 µg/m3). All of the metals concentrations were also lower than the guidelines set by World Health Organization (WHO), Ontario Ministry of the Environment and Argonne National Laboratory, USA NCRP (1975). From the concentrations, the enrichment factor were calculated. [ABSTRACT FROM AUTHOR]

On-line continuous monitoring of pulverised coal in fuel injection pipelines will allow power plant operators to understand fuel conveying conditions and ultimately to achieve higher combustion efficiency and lower pollutant emissions. This paper presents the design, implementation and trials of an instrumentation system for on-line non-intrusive measurement of pulverised coal in a power plant environment. An array of three identical electrostatic electrodes is housed in a sensing head to determine multiple measurement results from different electrode pairs. Flow parameters such as flow velocity, relative mass flow rate and fuel distribution between injection pipes can be obtained by fusing the multiple results. On-plant trials on 488 mm bore pneumatic conveying pipelines at a 600 MW coal-fired power plant were undertaken following preliminary system evaluation tests on a 50 mm bore laboratory test rig. Experimental results demonstrate that monitoring of pulverised coal flow is achieved using the developed instrumentation system under real industrial conditions. The developed technology is likely to find immediate applications, leading to improved performance of coal-fired power plants, efficient use of fuel, and subsequent reductions in emissions. [ABSTRACT FROM AUTHOR]

The subject of considerations is a spherical bifurcation pipe of a live steam made of steel P91, which is an element of a block of coal-fired power plant working with a 18K370 turbine. As experience shows, it is a very sensitive element of the boiler pipelines. An extreme work scenario for such a block has been adopted, in which the turbine is shutting down to a warm state three times in 24 hours. This is an action dictated by new challenges in the field of electricity network regulation, caused by increasing share of renewable energy sources. A one-sided numerical thermal-FSI analysis was performed. The focus was on hoop stresses as the most significant for the bifurcation pipe durability. The daily runs of these stresses at three points of the thickness of the bifurcation pipe sphere have been presented. Mechanical stresses derived from pressure and thermal stresses derived from temperature changes have been isolated. It has been shown that depending on the thermal load, some areas of the cross section are compressed while adjacent ones are stretched and vice versa. Thus, the mechanical stresses can be reduced under thermal conditions by thermal stresses. It has been proven that the bifurcation pipe is able to withstand the given extreme loads with stresses more than twice smaller than the yield point at a given operating temperature. [ABSTRACT FROM AUTHOR]

A radiological assessment of the workers and the public potentially affected by the operation of the Teruel Coal-fired Power Plant (the UPT Teruel), was performed under realistic assumptions. This assessment is part of a wider study to characterize the potential radiological impact of Naturally Occurring Radioactive Materials (NORM), in which our team, integrated by University of Extremadura and CIEMAT, is carrying out the study on coal-fired power plants sponsored by the Spanish Nuclear Safety Council (CSN). The study comprises the four biggest coal-fired power plants in Spain. Taking into account the working conditions and the plant specifications, six groups of workers were defined, established considering the 17 working tasks that could be of any importance for this assessment. For the public, considering that the area is barely inhabited, two different recreational scenarios were defined. Therefore, in-plant and outside measurements, needed for the assessment of each scenario, were carried out. Where experimental data were not available or measurements ranged within the natural background radiation values, modelling has been used. Every measured or estimated activity concentration in coal and other used materials or in the by-products generated in the power plant, for every radionuclide in the natural chains of 238U, 232Th and 40K, were below 0.32 Bq g-1. Those values are under the 0.5 Bq g-1 reference value for exemption and clearance of 238U, 232Th and 226Ra and the 5 Bq g-1 for 40K recommended in Europe. In the dose evaluations for six groups of workers, a maximum of 21 μSv a-1 was obtained (mainly due to the inhalation of resuspended particles). For both considered scenarios for the public, all the evaluated doses were below 4.3 μSv a-1. These results are considered negligible from a radiological point of view. In this work the models and assumptions used for the evaluation of workers and public doses, the assessment, as well as the most relevant experimental results and conclusions are presented. [ABSTRACT FROM AUTHOR]