scholarly journals Economizer water-wall damages initiated by feedwater impurities

2014 ◽  
Vol 68 (5) ◽  
pp. 559-563 ◽  
Author(s):  
Sonja Vidojkovic ◽  
Antonije Onjia ◽  
Aleksandar Devecerski ◽  
Nebojsa Grahovac ◽  
Aleksandra Nastasovic
Keyword(s):  
Power Plants ◽  
Thermal Power ◽  
Plant Stress ◽  
Electric Energy ◽  
X Ray Diffraction ◽  
Reliable Operation ◽  
Water Steam ◽  
Magnetite Layer ◽  
The Cost

The main causes of efficiency loss in thermal power plants are boiler tube failures that diminish unit reliability and availability, and raise the cost of the electric energy. For that reason, regular examination of boiler tubes is indispensable measure for prevention future malfunctions of power units. Microscopic examination of economizer inner wall microstructure, analysis of chemical composition of deposit using x-ray diffraction (XRD) and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS) has been performed in a subcritical power plant. Stress corrosion cracking, pitting corrosion, destroyed protective magnetite layer, presence of magnetite and hematite in deposit and corrosive impurities within the cracks were indicated the effect of inadequate quality of feedwater that can not entirely ensure reliable operation of the boiler. It may be stated that maintenance of present boiler does not provide its reliable operation. Extensive chemical control of water/steam cycle was recommended.

scholarly journals An Ultrasonic-Capacitive System for Online Characterization of Fuel Oils in Thermal Power Plants

Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 7979
Author(s):  
Mateus Mendes Campos ◽  
Luiz Eduardo Borges-da-Silva ◽  
Daniel de Almeida Arantes ◽  
Carlos Eduardo Teixeira ◽  
Erik Leandro Bonaldi ◽  
...  
Keyword(s):  
Flow Rate ◽  
Total Mass ◽  
Power Plants ◽  
Thermal Power ◽  
Electric Energy ◽  
Thermal Power Plants ◽  
Heating Value ◽  
Fuel Oils

This paper presents a ultrasonic-capacitive system for online analysis of the quality of fuel oils (FO), which are widely used to produce electric energy in Thermal Power Plants (TPP) due to their elevated heating value. The heating value, in turn, is linked to the quality of the fuel (i.e., the density and the amount of contaminants, such as water). Therefore, the analysis of the quality is of great importance for TPPs, either in order to avoid a decrease in generated power or in order to avoid damage to the TPP equipment. The proposed system is composed of two main strategies: a capacitive system (in order to estimate the water content in the fuel) and an ultrasonic system (in order to estimate the density). The conjunction of the two strategies is used in order to estimate the heating value of the fuel, online, as it passes through the pipeline and is an important tool for the TPP in order to detect counterfeit fuel. In addition, the ultrasonic system allows the estimation of the flow rate through the pipeline, hence estimating the amount of oil transferred and obtaining the total mass transferred as a feature of the system. Experimental results are provided for both sensors installed in a TPP in Brazil.

A Comparative Analysis of Using the pH and Ammonia Calculation Algorithms in the Chemical Monitoring Systems at Thermal Power Plants

Vestnik MEI ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 37-42
Author(s):  
Olga V. Yegoshina ◽  
◽  
Sofiya K. Zvonareva ◽  
Wei Lin Htet ◽  
◽  
...  
Keyword(s):  
Chemical Control ◽  
Power Plants ◽  
Thermal Power ◽  
Ammonia Concentration ◽  
Monitoring Systems ◽  
Mechanical Equipment ◽  
Reliable Operation ◽  
Chemical Monitoring ◽  
Calculation Algorithms ◽  
Comparison Of The Results

The reliability of thermal and mechanical equipment is largely associated with the introduction of cycle chemistry monitoring systems (CCMS). It is the operation of these systems that helps maintain the main parameters within the standardized ranges in a significantly more reliable manner and decrease the failure rate at power plants. Modern CCMSs use, as input information, the data of automatic chemical monitoring, laboratory chemical control, and thermal process parameters. Unfortunately, the large volume of chemical monitoring performed with the help of laboratory chemical control analyzers is a factor that causes less reliable operation of CCMS. The present study is intended for operating staff and employees of design organizations with the aim to decrease the volume of laboratory chemical control and reduce the sampling points load in terms of sampling flowrate. The possibility of applying indirect algorithms for calculating the most widely used indicators, such as pH and ammonia concentration, based on electrical conductivity measurements of direct and H-cationated samples in automatic chemical monitoring systems is considered. The results of calculation carried out using three algorithms for pH and ammonia concentration for laboratory and field conditions are given. A comparison of the results obtained from using three different methods for calculating the standardized indicators proceeding from experimental data is carried out.

Composite Сarbonaceous Сoal-Water Suspensions

2021 ◽  
Vol 1045 ◽  
pp. 212-225
Author(s):  
Olena Svietkina ◽  
Kostiantyn Bas ◽  
Sergiy Boruk ◽  
Roman Klishchenko ◽  
Oleksandr Yehurnov ◽  
...  
Keyword(s):  
Power Plants ◽  
Statistical Data ◽  
Main Type ◽  
Thermal Power ◽  
Electric Energy ◽  
Oil Refining ◽  
Thermal Power Plants ◽  
Water Suspensions ◽  
Ash And Slag Waste ◽  
Slag Waste

In Ukraine, up to 75% of all electricity is supplied by thermal power plants, the main type of fuel for which is coal, which leads to the release of ash and slag waste at power plants in huge quantities. Every 10 years (according to statistical data) the amount of ash and slag produced at thermal power plants doubles. The use and creation of new modified consumers of coal-water fuel (CWF) and coal-water suspensions (CWS) occurs periodically. The ease of handling suspensions is captivating: in the energy sector, they can serve as the basis for the effective disposal of numerous accumulated wastes from coal preparation and oil refining, a significant reduction in the consumption of minerals for generating heat and electric energy, and minimizing the effect of heat power engineering on public health and the state of nature.

Supplier Selection Criterion for SSCM in Indian Thermal Power Plant

2019 ◽  
pp. 240-257
Author(s):  
Suchismita Satapathy
Keyword(s):  
Power Plant ◽  
Thermal Power Plant ◽  
Power Plants ◽  
Thermal Power ◽  
Selection Criterion ◽  
Raw Material ◽  
Thermal Power Plants ◽  
Whole Process ◽  
Main Motive

All companies are dependent on their raw material providers. The same applies in the case of thermal power plants. The major raw material for a thermal power plant is the coal. There are a lot of companies which in turn provide this coal to the thermal power plant. Some of these companies are international; some are local, whereas the others are localized. The thermal power plants look into all the aspects of the coal providing company, before settling down for a deal. Some people are specifically assigned to the task of managing the supply chain. The main motive is to optimize the whole process and achieve higher efficiency. There are a lot of things which a thermal power plant looks into before finalizing a deal, such as the price, quality of goods, etc. Thus, it is very important for the raw material providers to understand each and every aspect of the demands of the thermal power plant. A combination of three methods—Delphi, SWARA, and modified SWARA—has been applied to a list of factors, which has later been ranked according to the weight and other relevant calculations.

Improvement of chemical control in the water-steam cycle of thermal power plants

2011 ◽  
Vol 31 (1) ◽  
pp. 119-128 ◽  
Author(s):  
Vladana N. Rajaković-Ognjanović ◽  
Dragana Z. Živojinovic ◽  
Branimir N. Grgur ◽  
Ljubinka V. Rajaković
Keyword(s):  
Chemical Control ◽  
Power Plants ◽  
Thermal Power ◽  
Thermal Power Plants ◽  
Water Steam ◽  
Steam Cycle

scholarly journals Increasing the energy efficiency of an enterprise by point compensating of power quality distortions

2019 ◽  
Vol 140 ◽  
pp. 04010 ◽  
Author(s):  
Egor Zamyatin ◽  
Irina Voytyuk ◽  
Elena Zamyatina
Keyword(s):  
Power Quality ◽  
Electric Energy ◽  
Electrical Energy ◽  
Implementation Costs ◽  
Three Stages ◽  
Pareto Method ◽  
Compensating Devices ◽  
Quality Of Electrical Energy ◽  
The Cost

The cost of any product includes the cost of electrical energy in its production. Enterprises use various methods to reduce the cost of electric energy. One of the most common methods is to reduce the loss of active power in the distribution network of an enterprise. This is achieved by compensating for distortions in the power quality of electrical energy using compensating devices. The method presented in the article offers point compensation of distortions in the power quality indicators of electric energy. Point connection of compensating devices allows their small number to be used. But, at the same time, a greater effect is achieved. The connection points of compensating devices are determined by the developed method. The method includes three stages: collecting data on consumers of electric energy at an enterprise and on the topology of the distribution electric network, analyzing the results obtained using the developed algorithm, and determining connection points using the Pareto method. Also, the developed method was compared with the classical ones according to the criterion of the ratio of implementation costs to the effect of its application.

Reliability Assessment of Piping in a Nuclear Power Plant Considering Flaw Detection Probability

2004 ◽  
Author(s):  
Hideo Machida ◽  
Norimichi Yamashita ◽  
Shinobu Yoshimura ◽  
Genki Yagawa
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Detection Probability ◽  
Nuclear Power ◽  
Power Plants ◽  
Plant Stress ◽  
Flaw Detection ◽  
Reliability Assessment ◽  
Flaw Detection Probability

This study was performed to clarify the effects of flaw detection probability on piping reliability of a nuclear power plant. Stress-corrosion cracking (SCC) is still sporadically detected in austenitic stainless steel piping in Japanese BWR plants. The suitability for continued service of cracked pipes is basically evaluated by using the “Rules on fitness -for service for nuclear power plants.” Here future inspection rules are employed. However, the possibility of undetection of existing cracks and that of inaccurate measurements cannot be eliminated in UT-based inspection. Thus a probabilistic fracture mechanics (PFM) analysis was carried out referring measured flaw size, and the reliability of piping was evaluated considering the possibility of undetection of existing cracks and that of inaccurate measurements. The results of the analysis indicate that, if the interval and quality of the inspection are maintained at a certain specified level, the possibility of undetection of existing cracks and that of inaccurate measurements less affect failure probability.

scholarly journals PECULIARITIES OF PROCUREMENT FOR DETERMINING THE CONTRACTOR OF ENGINEERING AND GEODESIC WORKS

2020 ◽  
Vol 1 (1) ◽  
pp. 31-41
Author(s):  
Anton V. Nikonov
Keyword(s):  
Power Plants ◽  
Thermal Power ◽  
Thermal Power Plants ◽  
Factors Affecting ◽  
Quality Of Work ◽  
Maximum Price ◽  
Definition Of ◽  
Price Offer

The article describes the difficulties faced by organizations engaged in engineering and geodetic work at power plants, with participation in procurement. It is shown that the majority of procurement participants are representatives of small and medium-sized businesses. The factors affecting the reduction in the price offer are given. It is noted that a decrease in the initial (maximum) price during the procurement procedures varies from 75 to 90%, which cannot but lead to a decrease in the quality of work, and often to falsification of reporting documentation. Conclusions are made on the example of three realized purchases by the definition of the contractor for geodetic work at thermal power plants.

scholarly journals SYSTEM OF AUTOMATIC CONTROL OF THE LEVEL OF STEAM POWER GENERATORS ON THE BASIS OF THE REGULATION CIRCUIT WITH SMOOTHING OF THE SIGNAL

2021 ◽  
Vol 22 (1) ◽  
pp. 287-297
Author(s):  
Dilnoza Umurzakova
Keyword(s):  
Automatic Control ◽  
Water Level ◽  
Power Plants ◽  
Thermal Power ◽  
Thermal Power Plants ◽  
Steam Generators ◽  
Wide Range ◽  
Steam Boilers ◽  
The Impact

The purpose of this article is to develop high-quality combined automatic control systems (ACS) for the water level in the drum of steam boilers of thermal power plants (TPPs), which can significantly improve the quality of regulation and increase the efficiency of TPPs in a wide range of load changes. To improve the quality of water level control in the drum of steam generators of nuclear power plants with a pressurized water-cooled power reactor (PWPR), it is proposed to use a combined automatic control system based on a control loop with a correcting PI-controller tuned to a symmetrical optimum, with smoothing the reference signal and device compensation of the most dangerous internal and external measurable disturbances. A technique has been developed for assessing the impact of changes in the quality characteristics of transients of combined self-propelled guns by the water level in the drum of steam boilers and steam generators on the safety, reliability, durability, and efficiency of thermal power equipment of thermal power plants. Comparison was made of direct indicators of the quality of three ACS (typical and three-pulse, digital system with an observer state, and the proposed combined ACS). The simulation results of transients of the proposed and typical three-pulse self-propelled guns confirmed the advantages of the first. ABSTRAK: Artikel ini bertujuan bagi membina sistem kombinasi automatik (ACS) berkualiti tinggi bagi aras air dalam drum dandang stim tenaga terma logi kuasa (TPP). Ini dapat meningkatkan mutu peraturan dan meningkatkan kecekapan TPP secara signifikan dengan pelbagai perubahan beban. Bagi meningkatkan kualiti kawalan aras air dalam drum penjana wap loji kuasa tenaga nuklear dengan reaktor berpendingin air bertekanan (PWPR). Gabungan sistem kawalan automatik berdasarkan gelung kawalan dengan pembetulan PI telah dicadangkan dan diselaraskan simetri secara optimum, dengan melancarkan isyarat rujukan dan pembetulan peranti dari gangguan yang boleh diukur dari dalam dan luar. Satu teknik telah dibina bagi menilai kesan perubahan ciri kualiti transien gabungan berjentera pada aras air di tong dandang stim dan drum penjana wap pada keselamatan, kebolehpercayaan, ketahanan dan kecekapan peralatan tenaga terma loji janakuasa. Perbandingan dibuat pada kualiti tiga ACS (sistem digital khas dan tiga signal dengan keadaan pemerhati dan gabungan ACS yang dicadangkan). Hasil sistem simulasi transien yang dicadangkan dan tiga signal biasa berjentera mengesahkan kelebihan pada yang pertama.

scholarly journals Aggregate estimation of investments in power plant units using a parametric power function

2020 ◽  
pp. 123-138
Author(s):  
Pavel Shchinnikov ◽  
◽  
Alina Frantseva ◽  
Ivan Sadkin ◽  
◽  
...  
Keyword(s):  
Power Plant ◽  
Power Function ◽  
Capital Investment ◽  
Power Plants ◽  
Thermal Power ◽  
Thermodynamic Characteristics ◽  
Engineering System ◽  
Parametric Function ◽  
Aggregate Estimation ◽  
The Cost

In the course of designing new generating equipment for power plants and their thermal circuits, in the absence of information about their cost, analog indicators and/or expert assessments are used in the design practice. This approach allows us to compare various options if they can be brought to a comparable form and when the same type of equipment is used. When it is necessary to compare options that differ not only in the specified capacity, but also in the equipment configuration, a more accurate assessment of investment is required. The article proposes a method for estimating capital investment in power plants using a power parametric function. Capital investment is assessed for each unit of the power plant and its engineering system. A special feature of the approach is that the higher the cost of the unit is, the higher its thermodynamic characteristics, power, time of load use, etc. These factors are taken into account by the exponent in the power function. In addition, the correction coefficients take into account the configuration of the equipment, its climatic design, and configuration features. The combination of factors that are taken into account in the power function makes it possible to obtain an estimate of the cost of equipment in different versions. The uniformity of the problem statement makes it possible to apply the approach both to design tasks and to scientific and applied tasks of comparing the existing, newly developed and promising technologies. This paper presents the updating and development of the method developed in previous years at the department of thermal power plants of NSTU. Equations for determining investment in the main units and technical systems of power plants are presented. Estimates of investment in power plants currently under construction in Russia are made. It is shown that investment in power plants in Russia is 20-50% lower than in the USA and Europe, and 20-30% higher than in China.

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