All these are assembled in the main building. There is the second building which houses the turbine hall 2 : steam generators and the turbine. Going further down the process flow diagram, there are condensers and high-voltage electricity supply lines which go off-site.
The site includes the building for recharging and storage of spent nuclear fuel in special ponds. Besides, plants are fitted with circulation cooling components, i. Depending on the reactor type, NPPs can have 1, 2 and 3 loops for the coolant. The reactor operates together with two condensing turbines and two generators. With that, the boiling-water reactor is the steam generator itself that provides for 1-loop arrangement. One-loop arrangement is rather simple but in this case radioactivity affects all components of the reactor unit making the biological shielding more complicated.
Two-loop arrangements are used at the plants with water-water reactors of WWER type. Water under pressure is supplied to the reactor core and heated up. The coolant energy is used in the steam generator to produce saturated steam. The second loop is non-radioactive. The reactor unit consists of one condensing turbine of MW or two turbines of MW each with corresponding generators.
To exclude contact of radioactive sodium with water, the second loop holding non-radioactive sodium is built. This makes the arrangement three-loop one. These methods are both qualitative and quantitative and aim to understand, and thus improve, human performance within the system.
Additionally, much of the research is focused on risk reduction — for example, design of a power plant to maximize redundancy in human performance during a mishap. Human error is a complicated process in itself and closely tied to cognition, information processing, system automation, team dynamics and biases inherent to humans.
It cannot be eliminated by training and familiarity alone, and system design plays a major role in susceptibility to error. The digital age has spurred many advances in processing power, sensor technology and data capture. These advances have resulted in situations where a very large amount of data can be captured and presented to the user. The large amount of information has to be processed with limited attention resources, which can result in human error.
This contribution will discuss human error and information processing along with the role of humans in modern power plants. Finally, trends in information overload will be discussed with applications to reducing human error in power plants. This study examines the upgrade of two forward-curved centrifugal induced draft fans, to support fuel blends with greater fractions of PRB coal for a MWe generating unit. After a post installation event, an audible periodic low frequency vibration in the breeching was noticed at loads ranging from 75—95 MWe.
A detailed investigation was conducted which included fluid dynamic and vibration analyses of the fan and system, as well as an assessment of the fan and motor performance characteristics. Results of the analyses revealed system resistances which generated operating points in the stall region on the fan performance curve. Non-uniform fan inlet flow distributions were characterized by axial and transverse distortion parameters. Data showed relatively high transverse distortion parameters over the affected load range with the maximum of Based on the data obtained and observed system behavior, it was determined the phenomenon responsible for the flow-induced vibration was the onset of rotating stall.
The magnitude of the pressure pulses associated with this low frequency vibration is capable of causing fatigue damage to large ductwork and producing unwanted acoustic emissions. In light of the large number of similar conversions performed throughout industry and increases in partial-load operation, the accurate diagnosis of such phenomenon is vital for reliable plant operations.
This work summarizes an effective and practical methodology for making such evaluations, while addressing issues of fan performance and system effects. For example, structures are engineered in part to have the capacity to survive the worst wind loads expected over the life of the structure. Likewise wind electric power systems should have the capacity to reliably survive the worst combination of high load and low wind. A frequent mistake is to average these annual ELCC estimates. A main contribution of this paper is to explain why the system design criteria should take the worst of the annual ELCC estimates over a number of years and not an average of annual ELCC estimates.
The empirical evidence shows that wind generation is an energy source, not a capacity resource. Boiler tube failures remain the leading cause of lost availability in power boilers across global markets. The need for strategic planning in regard to inspections, preventative maintenance and targeted replacements has never been greater. Identifying the root problem s is essential and must be properly managed for continued safety, reliability and availability. The process associated with integrating a boiler management program can be viewed as an insurmountable obstacle for many utility operators and owners.
In many cases, the cookie cutter approach that is often used results in insufficient reliability recovery. Specific challenges plants are faced with include the reduction of onsite engineers, aging workforces and equipment, and the need to remain competitive in a challenging global energy market. Plant managers are routinely faced with the complex task of determining the current condition of their equipment, forecasting outage budgets and schedules, and performing risk assessments.
The solutions to reducing the EFOR of a unit involves taking a comprehensive approach to boiler management utilizing unit specific operational training, advanced data management, and strategic inspection, maintenance and replacement prioritization. Implementing this comprehensive approach has awarded millions in savings for plant managers that have adopted this strategy. Unit specific strategic planning is necessary for all facilities that rely on these critical components.
Advanced technology must be adopted by all energy producers to ensure they remain competitive and profitable. In this paper, we present the experience of 10 years of collaboration between the Electric Research Institute and Pemex Refining to modernize the power electric systems of the National Refining System in Mexico, collaborating together to design an electrical energy system for distribution that can operate reliably at the increase in the quantity and quality of oil products with the integration of new processing plants.
We present the extensive cooperation between the personnel involved and in contrast unexecuted planning to implement the solutions. Also, after a decade of collaboration, we present the different scenarios, factors and challenges in the medium and long term that will assure that the electrical systems are in healthier conditions to operate for the next years and will achieve the required reliability of the national refining system for gasoline demand, to result in an operational reliability conferring to a World Class utility practice.
Ideal plant designs perform as intended. The goal of Reliability, Availability and Maintainability RAM processes is to convert designs into operational task requirements to achieve lifecycle goals. This paper introduces a risk management process to develop, maintain and use better risk-based failure management plans with an approach that is simple and clear. It predicts that software will become a more important RAM program development tool.
Coal-fired units are increasingly expected to operate at varying loads while simultaneously dealing with various operational influences as well as fuel variations. Maintaining unit load availability while managing adverse effects of various operational issues such as, flue gas temperature excursions at the SCR inlet, high steam temperatures and the like presents significant challenges.
Dynamic adjustment of sootblowing activities and different operational parameters is required to effectively control slagging, fouling and achieve reliability in unit operation. Closed-loop optimizers aim to reduce ongoing manual adjustments by control operators and provide consistency in unit operation. The Sootblowing Optimizer solution determines the need for sootblowing based on dynamic plant operating conditions, equipment availability and plant operational drivers.
This paper discusses implementation approach as well as operational experience with the Sootblowing Optimizer and presents longer-term operational trends showing unit load sustainability and heat rate improvement. When an RBD is required, Failure distribution and Outage distribution are requested as inputs for each block. Should field data exist, the two distributions can be obtained by managing data in the most appropriate manner. While the Failure distribution is often a right censored data set, the outage distribution is always a time-to-failure distribution obtained through the RRX interpolation.
Moreover, being the reliability approach conservative, the weibull 3P assumption is welcome, because the gamma value, in this particular circumstance, guarantees a minimum outage duration. However it has been noticed that while the 2P sometimes could be not-conservative enough, the 3P could result too much conservative with the risk of declaring a lower target than the actual one and hence with the consequence of not being commercially competitive. The proposed approach applies and develops the mixed weibull application, where each subpopulation distribution comes out from a single dataset, which represents a step forward after the traditional 2P and the more conservative 3P.
The circulating water system is a very important system in Ghazlan Steam Power Plant- MW, as it supplies the sea water to the tubes side of the Condensers during normal operation. A large butterfly cross-connect valve was installed at the circulating water pumps discharge header to isolate the pumps and the header for maintenance.
This paper explains the wrong design location of the valve in the piping as the root cause of the problem. Analysis with ASME reference will be presented. This paper will also present potential solutions and actions taken as a lesson learned to avoid occurrence in other plants. T and P are the oldest of a new class of creep-strength-enhanced ferritic steels CSEF approved for use in boilers and pressure vessels.
These newer alloys develop high strength through heat treatment, a rapid cooling or quenching to form martensite, followed by a temper to improve ductility. As a result, these alloys offer a much higher allowable stress which means thinner sections provide adequate strength for high-temperature service. The primary advantages of T91 materials over conventional low-alloy steels are: higher allowable stresses for a given temperature, improved oxidation, corrosion, creep and fatigue resistance.
T23 is also considered as a member of the family of CSEF steels. The alloying elements such as tungsten, vanadium, boron, titanium and niobium and heat treatment separate this alloy from the well defined T22 steel. Although, T23 is designated for tubing application, its piping counterpart P23 has a strong potential in header applications due to superior strength compared to P22 headers. Now that T and P have been in service for nearly 30 years, some shortcomings have become apparent.
During welding, the temperature varies from above the melting point of the steel to room temperature. The heat-affected zone HAZ is defined as the zone next to the fusion line at the edge of the weld metal that has been heated high enough to form austenite, i. On cooling, the austenite transforms to martensite.
This region has been, in effect, over-tempered by the welding and subsequent post-weld heat treatment PWHT. Over-tempering softens the tempered martensite with the associated loss of both tensile and creep strength. This region of low strength is subject to failure during service. Creep strength of T91 steel is obtained via a quenching process followed by controlled tempering treatment. Case studies will be presented, with the results of optical microscopy, scanning electron microscopy, hardness measurements and energy dispersive spectroscopy analysis.
One case study will discuss how the over-tempering caused a reduced creep strength, resulting in premature creep failure in a finishing superheater tube. A case study demonstrates how a short-term overheating excursion led to reheat cracking in T23 tubing. Another case will present creep degradation in T91 reheater steel tube due to high temperature exposures over-tempering.
Second, a zone based control approach is developed which is based on flexible definition of zones and results in a generic scalable solution that can be applied to buildings of different sizes and configuration. In addition, the approach provides redundancy to isolate unforeseen issues such as communication issues to the particular zones. The proposed monitoring and control approach is deployed in telecom base stations and retail stores to highlight the generic nature and scalability of the approach.
The energy saving potential and secondary benefits such as flexible localized operation of our unique zone-based control is highlighted in the results. Dissimilar metal welds between different grades of ferritic steels or between ferritic steel and austenitic nickel alloys are used extensively in power plants.
When such weldments are exposed to high temperature conditions, as might be found in service in a thermal power plant, local microstructural evolution will occur. This is due to diffusion, driven by chemical potential gradients, of solute atoms.
This can potentially lead to premature component failure by, for example, high temperature creep. Whilst finite element modelling of mechanical behavior and damage evolution is well established this is not the case for chemical diffusion and microstructural evolution at weld interfaces. Two approaches for modelling multiphase, multicomponent systems using this software will be presented and discussed and their implementation will be illustrated. The paper will present results on modelling a range of dissimilar metal interfaces of both the ferritic-ferritic type and the ferritic-austenitic type for example, grade 22 to grade 91 steel and grade 22 to Inconel The results obtained from modelling a grade 22 steel-Inconel system where the crystal structure of the matrix is different on either side of the weld will be compared with experimental observations on a weld overlaid tube component.
Also discussed are the options for further refining the computational model based on empirically observed phenomena, such as the unmixed zone of a weld. You do not have access to this content. For assistance or to subscribe, please contact us:. Sign in or create your free personal ASME account.
Sign into or create your free personal account. Sign In. Search Advanced Search. ISBN: Processing your request Please Wait. Basic View Expanded View. Topics: Indexing Machining. Topics: Combustion , Gas turbines , Image processing. Topics: Feedstock , Biomass , Boilers , Coal. Topics: Boilers , Coal.
Firing Tests of Biocoal. AlShoaibi and Ashwani K. Topics: Carbon dioxide , Sulfur. Salisu Ibrahim , Ahmed S. Topics: Combustion , Flames , Methane , oxidation , Sulfur. Larry Czarnecki and Paulo Oliveira. Topics: Design. Maclain M. Holton , Michael S. Klassen , Leo D. Eskin , Richard J. Joklik and Richard J. Topics: Energy generation , Natural gas , Ethanol , Emissions. Topics: Turbulence , Energy budget Physics , Combustion chambers.
Fu and Christopher Y. Topics: Solid waste disposal , Fuel gasification , Particle size. Topics: Coal , Pyrolysis. DeVon A. Washington and Howard N. Topics: Combustion , Oxygen. Teresa A. Wierzbicki , Ivan C. Lee and Ashwani K. Topics: Heat , Combustion , Combustion chambers. Trehan , H. Molintas and A. Topics: Wood products , Carbon dioxide , Fuel gasification. Richard Scenna and Ashwani K. Topics: Modeling , oxidation , Soot. Topics: Fluids , Fuels , Boilers , Natural gas. Topics: Biomass , Power stations.
Zheming Zhang and Ramesh Agarwal. Topics: Pressure , Boilers , Heating. Modeling of Superheater Operation in a Steam Boiler. Topics: Superheaters , Boilers , Modeling. David S. Moelling and James Malloy. Topics: Boiling , Heat recovery steam generators. Terrence Olson, Jr.
Topics: Power stations. Dereje Shiferaw and Robert Broad. Darren M. Nightingale and Earl Proud. Topics: Optimization , Condensers steam plant. Topics: Condensers steam plant , Steam , Combined cycles. The Third Option for Meeting b Requirements. Charles F. Geir Skaugen , Harald T. Walnum , Brede A. Hagen , Daniel P. Clos , Marit J. Thomas R. Muldoon , Bob Cashner and Sara Vestfals. Topics: Forging , High pressure Physics , Feedwater.
Topics: Engineering prototypes , Feedwater , Shells. Ranga Nadig and Dave Sanderlin. Topics: Condensers steam plant , Steam , Water. James A. Kocher , Robert Frazee and Matthew Wolf. Topics: Reliability , Eddy current testing , Condensers steam plant , Nuclear power stations. Kellen J. Topics: Temperature , Feedwater , Design , Shells. Topics: Steam turbines , Heat transfer coefficients.
Mike Jones and Robert Crossland. Topics: Engineering design processes , Blades , Nuclear power stations. Randall M. Attix and D. Topics: Generators. Jane A. Topics: Social networking. Topics: Cooling , Copper , Stators , Water. Generator Auxiliary Gas System Upgrades. Komandur Sunder Raj. Topics: Condensers steam plant. Topics: Optimization , Condition monitoring , Fossil fuels. Qingsheng Lin and Todd Collins. Topics: Steam. Yizhou Yan. Topics: Gaseous fuels , Transients Dynamics , Combined cycle power stations.
Washington and LeRoy N. Ian Judd. Topics: Maintenance , Combined heat and power. Pamela Hamblin-Smoske. Topics: Pipes , Strategic planning. Jason C. Lee and Michael Coyle. Topics: Boilers , Coal , Natural gas. Reynir S. Atlason and Runar Unnthorsson. Topics: Valves , needles , Geothermal power stations. Selection tables and advice on trap selection for a range of different processes are included in this tutorial, including boiling pans, retorts, digesters, coppers, reboilers, evaporators and vulcanisers. Selection tables and advice on trap selection for a range of different processes are included in this tutorial.
Selection tables and advice on trap selection for different types of steam mains, headers and off-takes are included in this tutorial, together with process vats and pressure reducing valve stations. The presence of air has a devastating effect on steam systems and processes. The basic theory of air venting is explained in this tutorial, plus advice on air vent location.
Some of the many different applications for air vents are described in this tutorial, including steam mains, bypasses, jacketed vessels and rotating cylinders. Other issues such as venting large volumes of air, group air venting and the substitution of thermostatic steam traps are also considered. Indiscriminate maintenance of steam traps wastes money. This tutorial considers a planned approach to steam trap testing and maintenance, with recommended methods and equipment.
A large amount of inaccurate and misleading information has been written on this subject. This tutorial gives clear, accurate information regarding the energy consumption of different trap types.
These are often neglected to save costs; but strainers, stop valves, check valves, separators, gauge glasses and vacuum breakers all have their part to play in an efficient steam system. This block explains why, and explores the different types available. Isolation valves are used for diverting process media, facilitating maintenance, equipment removal and shutdown. The operation, application and construction of gate, globe, piston and diaphragm valves are studied in this tutorial.
Check non-return valves are installed in pipelines to allow flow in one direction only; helping to protect equipment and processes. The operation, benefits, applications and selection of different designs, including lift, disc, swing and wafer check valves are explained in this tutorial.
Strainers arrest pipeline debris such as scale, rust, jointing compound and weld metal in pipelines, protecting equipment and processes. This tutorial considers the range of strainer and filter types in use and how to size and select them for different applications. Separators are designed to efficiently remove the moisture from steam flow. The application and selection of different types are considered here. These small items of equipment have a variety of important applications throughout steam systems and process equipment. The different types available are studied in this tutorial.
Proper condensate removal is essential to heat exchanger efficiency and long service life. An explanation of how heat exchangers operate. It introduces the subject of stall, and why and how the best trapping device is selected to maximise system efficiency. This Block discusses the removal of condensate from heat exchange equipment supplied by saturated steam and fitted with a temperature control valve on the steam line to the heat exchanger and A steam trapping device on the condensate line from the heat exchanger.
Heat exchangers are often bought oversized for the required duty. This tutorial looks at the reasons why, the effects this has and related requirements, such as trap sizing for oversized exchangers. A fully worked-through example for calculating stall and selecting a condensate removal solution for a heat exchange application. A simple method of calculating stall is to use a stall chart. This tutorial explains the use of a chart to calculate stall for a constant secondary flowrate with a varying inlet temperature.
Not all heat exchangers are required to operate with a constant secondary flow. Typical applications might include the provision of hot water to batch processes such as tanks and vats. Using a chart to calculate stall for a constant secondary flowrate with a varying outlet temperature. This tutorial considers methods of overcoming condensate drainage problems, such as ensuring gravity drainage, installing an automatic pump trap device, or controlling the pressure in the steam space.
Relaying condensate back to the boiler house reduces costs. Pipe sizing and layout is discussed for drain lines, discharge lines, and pumped lines. The effects of lift and backpressure are explained; and how to reduce overall costs by utilising flash steam. An introduction to the reasons for condensate recovery and return, including energy costs, water charges, effluent restrictions and water treatment costs.
Includes sample calculations for potential savings. Considerations surrounding the design and layout of condensate return pipework, including drain lines to steam traps, discharge lines from traps, common return lines and pumped return lines. Includes the effect of trap types used, the effect of different pressures and discharging condensate into flooded mains.
A guide to sizing condensate lines to and from steam traps, including examples and calculations using the condensate pipe sizing chart. A basic introduction to pumping terminology, including vapour pressure and static head. Includes a description of the operation, application and comparable benefits of electrical centrifugal and mechanical condensate pumps, with sizing examples for pumps and pump discharge lines. The benefits of recovering flash steam, how it is done and how flash steam can be applied elsewhere in the plant to maximise overall efficiency.
Recommendations for special circumstances, including lifting condensate to a higher level return line, and dealing with contaminated condensate. Why is it necessary to desuperheat steam? What types of desuperheater exist, where are they used, and how are they installed?
Basic types and more sophisticated types of desuperheater and their applications are discussed in some detail. This tutorial introduces the common types of desuperheater in regular use, their limitations and typical applications. Superheated steam has important advantages on certain applications, for example, when used in power stations to drive turbines. For efficient use on heating applications however, the steam must be desuperheated. This tutorial considers basic desuperheating theory and calculations. Additional desuperheater designs such as the venturi and variable orifice types are covered in this tutorial.
A comparison of all types is included at the end. A number of important considerations need to be taken into account when installing desuperheaters. This tutorial covers issues such as water quality and pressure control. A desuperheater selection chart and a list of applications are also included. Your closest Spirax Sarco is. This region has not yet joined our new website.
You will now continue to the existing site for Spirax Sarco. Global Search Navigation. Learn about steam. Introduction The introduction of steam as a useful and powerful purveyor of energy. Steam - the energy fluid This introductory tutorial describes the many benefits and uses of steam in industry today. Steam and the organisation The benefits of steam are viewed differently by individuals according to their role and priorities. The steam and condensate loop How is steam generated, distributed, controlled and used? Engineering Units An overview of the units of measurement used in the Steam and Condensate Loop including temperature, pressure, density, volume, heat, work and energy.
Superheated Steam An explanation of the properties and uses of superheated steam such as for electricity generation. Measurement of Steam Consumption Methods of measuring steam consumption, from the very basic to sophisticated flow metering, are explained in this tutorial. Steam Consumption of Pipes and Air Heaters Steam will condense and give up its enthalpy of evaporation on the walls of any pipe or tube at a lower temperature. The boiler house Various types of boilers and fuels are discussed, alongside the best ways in which to get the best out of this important part of the steam plant.
Introduction An overview of boiler regulations, with an evaluation of fuel types and comparisons Shell Boilers Overview of the different types of shell boiler with layouts, heat and steam release considerations plus pressure and output limitations Water Tube Boilers Description of water tube boilers including operation, types and benefits; also, a brief synopsis on how they are applied to combined heat and power generation. Miscellaneous Boiler Types Economisers and Superheaters An explanation of specialist boiler types and other specialist features.
Generators for Operators (Steam Plant Operations Book 1) - Kindle edition by Wayne Smith. Download it once and read it on your Kindle device, PC, phones or . Boiler Operator (Steam Plant Operations Book 1) - Kindle edition by Wayne Smith . Download it once and read it on your Kindle device, PC, phones or tablets.
Boiler Ratings This tutorial explains the three most commonly used boiler ratings: The 'From and at' rating for evaporation, the kW rating for heat output, and boiler horsepower. Steam Headers and Off Takes This tutorial looks at steam header arrangements and other design considerations necessary for efficient warm-up, good steam quality and proper steam distribution from the boiler house. The Feedtank and Feedwater Conditioning All aspects of the design, construction and operation of feedtanks and semi-deaerators, including calculations. Bottom Blowdown Factors surrounding the removal of suspended solids from the boiler, including valves, piping and blowdown vessels, with calculations.
Pressurised Deaerators The need to remove gases from boiler feedwater and the operation of a pressurised deaerator, plus calculations. Flowmetering Fluid characteristics and flow theory including Bernoulli's theorem and Reynolds' numbers are introduced and developed to provide basic metering theory and techniques. Fluids and Flow Users may wish to measure the flow of steam to help with plant efficiency, energy efficiency, process control or costing purposes.
Principles of Flowmetering A detailed examination of the principles and terminology surrounding the topic of flowmetering, including accuracy, repeatability and turndown. Types of Steam Flowmeter The operation, advantages and limitations of different types of steam flowmeter, including orifice plate, variable area and vortex shedding devices.
Installation System design, installation and maintenance considerations for steam flowmeters, including the use of strainers, separators and flow straighteners, together with piping layouts. Basic control theory Control theory is discussed from fundamental proportional action to PID control.
Control loops and dynamics An explanation of each component of a control system, including valves, actuators, sensors and controllers; together with an introduction to methods of control and system dynamics, including simple control loops and feedback systems. Choice and Selection of Controls This tutorial will concentrate on available automatic control choices such as self-acting, pneumatic or electric and the decisions which must be made before selection. Installation and commissioning of controls Practical installation and commissioning advice for valves, actuators, sensors, controllers and more.
Computers in Controls A look at the more recent developments in control involving the use of information technology. Control Valves This tutorial briefly describes the basic components of different types of linear and rotary action control valves available for use in steam and water systems. Control Valve Capacity Valves need to be measured on their capacity to pass fluid.
Control Valve Sizing For Water Systems This tutorial briefly describes how to use flow coefficients to size valves for water systems, the difference between using two-port and three-port valves and the effect of these valves on pressure drop, flow and water system characteristics. Controllers and Sensors Controllers and sensors are important parts of the control system; without information from the sensor, the controller cannot make a decision and instruct the valve to move. Control hardware: self-acting actuation Basic self-acting control theory is discussed, alongside the different types of direct-acting and pilot-operated valves, controllers, and applications for the proper selection of temperature and pressure control of steam and water systems.
Since only 10 bhp is needed, 20 bhp of steam goes up the stack as wasted energy. The NBIC addresses requirements for piping together boilers that have different maximum allowable working pressures. In contrast, conductive composite sensors made of the same polymeric components as the insulation system itself monitor the actual environmentally and operationally induced degradation of the component insulation and provide a quick, objective indication of the current condition and remaining design life of the insulation. The name of the unlicensed person currently employed and if the unlicensed person has made an application for examination with the Bureau of Boiler and Pressure Vessel Compliance; and. For parallel flow, the hottest flue gases come into contact with the coldest feedwater; for counterflow, the reverse occurs. The heat in the flue gas leaving the boiler or economizer is recovered by the incoming air, thereby reducing the flue gas temperature and increasing efficiency.
Self-acting Temperature Controls This tutorial gives a basic introduction to what self-acting temperature control systems are and how they operate. Control applications A brief summary of, and advice on, temperature, pressure, flow and level control methods to suit various types of steam applications, with consideration to surplussing control, differential pressure control, and cascade control and installation thereof.