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Sample records for boiler tubes

  1. Failure analysis of boiler tube

    International Nuclear Information System (INIS)

    Mehmood, K.; Siddiqui, A.R.

    2007-01-01

    Boiler tubes are energy conversion components where heat energy is used to convert water into high pressure superheated steam, which is then delivered to a turbine for electric power generation in thermal power plants or to run plant and machineries in a process or manufacturing industry. It was reported that one of the tubes of a fire-tube boiler used in a local industry had leakage after the formation of pits at the external surface of the tube. The inner side of the fire tube was working with hot flue gasses with a pressure of 10 Kg/cm/sup 2/ and temperature 225 degree C. The outside of the tube was surrounded by feed water. The purpose of this study was to determine the cause of pits developed at the external surface of the failed boiler tube sample. In the present work boiler tube samples of steel grade ASTM AI61/ASTM A192 were analyzed using metallographic analysis, chemical analysis, and mechanical testing. It was concluded that the appearance of defects on the boiler tube sample indicates cavitation type corrosion failure. Cavitation damage superficially resembled pitting, but surface appeared considerably rougher and had many closely spaced pits. (author)

  2. Boiler tube failure prevention in fossil fired boilers

    International Nuclear Information System (INIS)

    Townsend, R.D.

    1993-01-01

    It is the common experience of power generating companies worldwide that the main causes of forced outages on power plant are those due to boiler tube failures on fossil units. The main reason for the large number of failures are the severe environmental conditions in fossil boilers as the effects of stress, temperature, temperature gradients, corrosion, erosion and vibration combine to produce degradation of the tube steel. Corrosion by oxidation, by combustion products and by impure boiler water can significantly reduce the tube wall thickness and result in failure of a tube many years before its designed service life. Errors can also occur in the design manufacturer, storage, operation, and maintenance of boiler tubing and the wrong material installed in a critical location can lead to premature failure. Altogether, experts in the US and UK, from many different disciplines, have identified seven broad categories of boiler tube failure mechanisms. 1 tab., 2 figs

  3. Stress-Assisted Corrosion in Boiler Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Preet M Singh; Steven J Pawel

    2006-05-27

    A number of industrial boilers, including in the pulp and paper industry, needed to replace their lower furnace tubes or decommission many recovery boilers due to stress-assisted corrosion (SAC) on the waterside of boiler tubes. More than half of the power and recovery boilers that have been inspected reveal SAC damage, which portends significant energy and economic impacts. The goal of this project was to clarify the mechanism of stress-assisted corrosion (SAC) of boiler tubes for the purpose of determining key parameters in its mitigation and control. To accomplish this in-situ strain measurements on boiler tubes were made. Boiler water environment was simulated in the laboratory and effects of water chemistry on SAC initiation and growth were evaluated in terms of industrial operations. Results from this project have shown that the dissolved oxygen is single most important factor in SAC initiation on carbon steel samples. Control of dissolved oxygen can be used to mitigate SAC in industrial boilers. Results have also shown that sharp corrosion fatigue and bulbous SAC cracks have similar mechanism but the morphology is different due to availability of oxygen during boiler shutdown conditions. Results are described in the final technical report.

  4. Elevated temperature failures in boiler tubes - case studies

    International Nuclear Information System (INIS)

    Gowrisankar, I.; Bandyopadhyay, G.

    1989-01-01

    Metallurgical investigation of boiler tube failures enables identification of failure mechanisms and the underlying cause related to boiler conditions. Some case studies in short term overheating, prolonged overheating and low cycle fatigue failures in boiler tubes are discussed. (author)

  5. CFD modeling of a boiler's tubes rupture

    International Nuclear Information System (INIS)

    Rahimi, Masoud; Khoshhal, Abbas; Shariati, Seyed Mehdi

    2006-01-01

    This paper reports the results of a study on the reason for tubes damage in the superheater Platen section of the 320 MW Bisotoun power plant, Iran. The boiler has three types of superheater tubes and the damage occurs in a series of elbows belongs to the long tubes. A three-dimensional modeling was performed using an in-house computational fluid dynamics (CFD) code in order to explore the reason. The code has ability of simultaneous solving of the continuity, the Reynolds-Averaged Navier-Stokes (RANS) equations and employing the turbulence, combustion and radiation models. The whole boiler including; walls, burners, air channels, three types of tubes, etc., was modeled in the real scale. The boiler was meshed into almost 2,000,000 tetrahedral control volumes and the standard k-ε turbulence model and the Rosseland radiation model were used in the model. The theoretical results showed that the inlet 18.9 MPa saturated steam becomes superheated inside the tubes and exit at a pressure of 17.8 MPa. The predicted results showed that the temperature of the steam and tube's wall in the long tubes is higher than the short and medium size tubes. In addition, the predicted steam mass flow rate in the long tube was lower than other ones. Therefore, it was concluded that the main reason for the rupture in the long tubes elbow is changing of the tube's metal microstructure due to working in a temperature higher than the design temperature. In addition, the structural fatigue tension makes the last elbow of the long tube more ready for rupture in comparison with the other places. The concluded result was validated by observations from the photomicrograph of the tube's metal samples taken from the damaged and undamaged sections

  6. Computer simulation of the fire-tube boiler hydrodynamics

    Directory of Open Access Journals (Sweden)

    Khaustov Sergei A.

    2015-01-01

    Full Text Available Finite element method was used for simulating the hydrodynamics of fire-tube boiler with the ANSYS Fluent 12.1.4 engineering simulation software. Hydrodynamic structure and volumetric temperature distribution were calculated. The results are presented in graphical form. Complete geometric model of the fire-tube boiler based on boiler drawings was considered. Obtained results are suitable for qualitative analysis of hydrodynamics and singularities identification in fire-tube boiler water shell.

  7. Maintenance of immersion ultrasonic testing on the water tube boiler

    International Nuclear Information System (INIS)

    Ishiyama, Toru; Kawasaki, Ichio; Miura, Hirohito

    2014-01-01

    There are 4-boiler in nuclear fuel cycle engineering laboratories (NCL). These boilers have been operated in the long term over 20 years. One of them, the leakage of boiler water was found at one of the generating tubes, and 2 adjoining generating tubes were corroded in Dec, 2011. These generating tubes were investigated by immersion ultrasonic testing (UT) for measure thickness of the tube. As a result, thinner tube was found in a part of a bend and near the water drum. These parts are covered with sulfide deposit, it seems that the generating tubes were corroded by sulfide. (author)

  8. CFD investigation of flow through internally riffled boiler tubes

    DEFF Research Database (Denmark)

    Rasmussen, Christian; Houbak, Niels; Sørensen, Jens Nørkær

    1997-01-01

    In this paper we show how to model the swirling flow in an internally riffled boiler tube. The flow field is visualized and the results are compared with measurements.......In this paper we show how to model the swirling flow in an internally riffled boiler tube. The flow field is visualized and the results are compared with measurements....

  9. Failure analysis of boiler tubes in lakhra coal power plant

    International Nuclear Information System (INIS)

    Shah, A.; Baluch, M.M.; Ali, A.

    2010-01-01

    Present work deals with the failure analysis of a boiler tube in Lakhra fluidized bed combustion power station. Initially, visual inspection technique was adopted to analyse the fractured surface. Detailed microstructural investigations of the busted boiler tube were carried out using light optical microscope and scanning electron microscope. The hardness tests were also performed. A 50 percent decrease in hardness of intact portion of the tube material and from area adjacent to failure was measured, which was found to be in good agreement with the wall thicknesses measured of the busted boiler tube i.e. 4 mm and 2 mm from unaffected portion and ruptured area respectively. It was concluded that the major cause of failure of boiler tube is erosion of material which occurs due the coal particles strike at the surface of the tube material. Since the temperature of boiler is not maintained uniformly. The variations in boiler temperature can also affect the material and could be another reason for the failure of the tube. (author)

  10. Failure analysis of the boiler water-wall tube

    OpenAIRE

    S.W. Liu; W.Z. Wang; C.J. Liu

    2017-01-01

    Failure analysis of the boiler water-wall tube is presented in this work. In order to examine the causes of failure, various techniques including visual inspection, chemical analysis, optical microscopy, scanning electron microscopy and energy dispersive spectroscopy were carried out. Tube wall thickness measurements were performed on the ruptured tube. The fire-facing side of the tube was observed to have experienced significant wall thinning. The composition of the matrix material of the tu...

  11. Creep analysis of boiler tubes by fem | Taye | Zede Journal

    African Journals Online (AJOL)

    In this paper an analysis is developed for the determination of creep deformation of an axisymmetric boiler tubes subjected to axisymmetric loads. The stresses and the permanent strains at a particular time and at the steady state condition, resulting from loading of the tube under constant internal pressure and elevated ...

  12. Modelling and simulating fire tube boiler performance

    DEFF Research Database (Denmark)

    Sørensen, K.; Condra, T.; Houbak, Niels

    2003-01-01

    A model for a flue gas boiler covering the flue gas and the water-/steam side has been formulated. The model has been formulated as a number of sub models that are merged into an overall model for the complete boiler. Sub models have been defined for the furnace, the convection zone (split in 2......: a zone submerged in water and a zone covered by steam), a model for the material in the boiler (the steel) and 2 models for resp. the water/steam zone (the boiling) and the steam. The dynamic model has been developed as a number of Differential-Algebraic-Equation system (DAE). Subsequently Mat......Lab/Simulink has been applied for carrying out the simulations. To be able to verify the simulated results experiments has been carried out on a full scale boiler plant....

  13. Failure analysis of the boiler water-wall tube

    Directory of Open Access Journals (Sweden)

    S.W. Liu

    2017-10-01

    Full Text Available Failure analysis of the boiler water-wall tube is presented in this work. In order to examine the causes of failure, various techniques including visual inspection, chemical analysis, optical microscopy, scanning electron microscopy and energy dispersive spectroscopy were carried out. Tube wall thickness measurements were performed on the ruptured tube. The fire-facing side of the tube was observed to have experienced significant wall thinning. The composition of the matrix material of the tube meets the requirements of the relevant standards. Microscopic examinations showed that the spheroidization of pearlite is not very obvious. The failure mechanism is identified as a result of the significant localized wall thinning of the boiler water-wall tube due to oxidation.

  14. Simulasi Thermal Stress Pada Tube Superheater Package Boiler

    OpenAIRE

    Hamdani

    2013-01-01

    This project investigates the thermal stress behavior and the mechanisms of superheater tube failure with experimental method and numerical analysis. First of all the procedures for failure analysis were applied to determine the root cause of them. A visual assessment of boiler critical pressure parts was carried out, and then the failed tube is examined by nondestructive evaluation. For the numerical domain, initially the elastic solution for a superheater tube subjected to an internal press...

  15. Hybrid Intelligent Warning System for Boiler tube Leak Trips

    Directory of Open Access Journals (Sweden)

    Singh Deshvin

    2017-01-01

    Full Text Available Repeated boiler tube leak trips in coal fired power plants can increase operating cost significantly. An early detection and diagnosis of boiler trips is essential for continuous safe operations in the plant. In this study two artificial intelligent monitoring systems specialized in boiler tube leak trips have been proposed. The first intelligent warning system (IWS-1 represents the use of pure artificial neural network system whereas the second intelligent warning system (IWS-2 represents merging of genetic algorithms and artificial neural networks as a hybrid intelligent system. The Extreme Learning Machine (ELM methodology was also adopted in IWS-1 and compared with traditional training algorithms. Genetic algorithm (GA was adopted in IWS-2 to optimize the ANN topology and the boiler parameters. An integrated data preparation framework was established for 3 real cases of boiler tube leak trip based on a thermal power plant in Malaysia. Both the IWSs were developed using MATLAB coding for training and validation. The hybrid IWS-2 performed better than IWS-1.The developed system was validated to be able to predict trips before the plant monitoring system. The proposed artificial intelligent system could be adopted as a reliable monitoring system of the thermal power plant boilers.

  16. CFD modeling of a boiler's tubes rupture

    Energy Technology Data Exchange (ETDEWEB)

    Rahimi, Masoud; Khoshhal, Abbas; Shariati, Seyed Mehdi [Chemical Engineering Department, Faculty of Engineering, Razi University, Kermanshah (Iran)

    2006-12-15

    This paper reports the results of a study on the reason for tubes damage in the superheater Platen section of the 320MW Bisotoun power plant, Iran. The boiler has three types of superheater tubes and the damage occurs in a series of elbows belongs to the long tubes. A three-dimensional modeling was performed using an in-house computational fluid dynamics (CFD) code in order to explore the reason. The code has ability of simultaneous solving of the continuity, the Reynolds-Averaged Navier-Stokes (RANS) equations and employing the turbulence, combustion and radiation models. The whole boiler including; walls, burners, air channels, three types of tubes, etc., was modeled in the real scale. The boiler was meshed into almost 2,000,000 tetrahedral control volumes and the standard k-{epsilon} turbulence model and the Rosseland radiation model were used in the model. The theoretical results showed that the inlet 18.9MPa saturated steam becomes superheated inside the tubes and exit at a pressure of 17.8MPa. The predicted results showed that the temperature of the steam and tube's wall in the long tubes is higher than the short and medium size tubes. In addition, the predicted steam mass flow rate in the long tube was lower than other ones. Therefore, it was concluded that the main reason for the rupture in the long tubes elbow is changing of the tube's metal microstructure due to working in a temperature higher than the design temperature. In addition, the structural fatigue tension makes the last elbow of the long tube more ready for rupture in comparison with the other places. The concluded result was validated by observations from the photomicrograph of the tube's metal samples taken from the damaged and undamaged sections. (author)

  17. Oxygen pitting failure of a bagasse boiler tube

    CSIR Research Space (South Africa)

    Heyes, AM

    2001-04-01

    Full Text Available Examination of a failed roof tube from a bagasse boiler showed transverse through-cracks and extensive pitting. The pitting was typically oxygen induced pitting and numerous fatigue cracks had started within these pits. It is highly probable...

  18. Reliability of non-heated tube bends of boilers

    International Nuclear Information System (INIS)

    Bugaj, N.V.; Akhremenko, V.L.; Zamotaev, V.S.

    1984-01-01

    Bend failures are described for non-heated boiler tubes of 12Kh1MF and 20 steels. Methods of reliability evaluations are presented which permit revealing and replacing the bends with inadequate resources. Influences of operation conditions on bend durability is shown as well as the factors which are dominating at bend failures

  19. Metallurgical Analysis of Cracks Formed on Coal Fired Boiler Tube

    Science.gov (United States)

    Kishor, Rajat; Kyada, Tushal; Goyal, Rajesh K.; Kathayat, T. S.

    2015-02-01

    Metallurgical failure analysis was carried out for cracks observed on the outer surface of a boiler tube made of ASME SA 210 GR A1 grade steel. The cracks on the surface of the tube were observed after 6 months from the installation in service. A careful visual inspection, chemical analysis, hardness measurement, detailed microstructural analysis using optical and scanning electron microscopy coupled with energy dispersive X-ray spectroscopy were carried out to ascertain the cause for failure. Visual inspection of the failed tube revealed the presence of oxide scales and ash deposits on the surface of the tube exposed to fire. Many cracks extending longitudinally were observed on the surface of the tube. Bulging of the tube was also observed. The results of chemical analysis, hardness values and optical micrographs did not exhibit any abnormality at the region of failure. However, detailed SEM with EDS analysis confirmed the presence of various oxide scales. These scales initiated corrosion at both the inner and outer surfaces of the tube. In addition, excessive hoop stress also developed at the region of failure. It is concluded that the failure of the boiler tube took place owing to the combined effect of the corrosion caused by the oxide scales as well as the excessive hoop stress.

  20. A risk approach to the management of boiler tube thinning

    International Nuclear Information System (INIS)

    Noori, Soudabeh A.; Price, John W.H.

    2006-01-01

    A large set of industrial thickness inspection data covering four boiler units of a power station over a period of five years was made available to the authors. The measurements were made in regions of the boiler where corrosion/erosion was the major cause of failure of the boiler tubes. There were over 40,000 separately measured data points in the data and all were collected with some care and expense. In the development of maintenance strategies for equipment, this type of data is typical of the data that must be collected and assessed. This data thus represents an opportunity to evaluate the ability to generate a useful risk approach to the management of the tubing. An important example of a risk-based approach is the American Petroleum Institute (API) Risk Based Inspection ('RBI'), API 581. A variety of problems were encountered applying this to boiler tubes. The problems include irrelevant API 581 corrosion rate tables, lack of information on how to analyse inspection data, difficulty of dealing with multiple inspection categories and lack of suitable direction for programming inspection intervals

  1. Modelling of a one pass smoke tube boiler

    DEFF Research Database (Denmark)

    Karstensen, Claus M. S.; Sørensen, Kim

    2004-01-01

    A nonlinear state-space model with five states describing a one pass smoke tube boiler has been formulated. By means of mass- and energy-balance the model describes the dynamics of the Furnace, the Convection Zone and the Water/Steam Part and the three sub models are merged into an overall model....... The model is further linearized for use in a linear control design. The simulations have been carried out by means of MATLAB/SIMULINK and the models have been verified with measurements from a full scale boiler plant. Parameters in the model that are difficult to calculate have been estimated and the method...

  2. Thermal design of horizontal tube boilers: numerical and experimental investigation

    International Nuclear Information System (INIS)

    Roser, Robert

    1999-01-01

    This work concerns the thermal design of kettle re-boilers. Current methods are highly inaccurate, regarded to the correlations for external heat transfer coefficient at one tube scale, as well as to two-phase flow modelling at boiler scale. The aim of this work is to improve these thermal design methods. It contains an experimental investigation with typical operating conditions of such equipment: an hydrocarbon (n-pentane) with low mass flux. This investigation has lead to characterize the local flow pattern through void fraction measurements and, from this, to develop correlations for void fraction, pressure drop and heat transfer coefficient. The approach is original, since the developed correlations are based on the liquid velocity at minimum cross section area between tubes, as variable characterizing the hydrodynamic effects on pressure drop and heat transfer coefficient. These correlations are shown to give much better results than those suggested up to now in the literature, which are empirical transpositions from methods developed for inside tube flows. Furthermore, the numerical code MC3D has been applied using the correlations developed in this work, leading to a modelization of the two-phase flow in the boiler, which is a significant progress compared to current simplified methods. (author) [fr

  3. Boiler and HRSG tube failures. Lesson 4: Hydrogen damage

    Energy Technology Data Exchange (ETDEWEB)

    Dooley, R. Barry; Bursik, Albert

    2010-02-15

    University 101 courses are typically designed to help incoming first-year undergraduate students to adjust to the university, develop a better understanding of the college environment, and acquire essential academic success skills. Why are we offering a special Boiler and HRSG Tube Failures PPChem 101? The answer is simple, yet very conclusive: There is a lack of knowledge on the identification of tube failure mechanisms and for the implementation of adequate counteractions in many power plants, particularly at industrial power and steam generators. There is a lack of knowledge to prevent repeat tube failures. The vast majority of BTF/HTF have been, and continue to be, repeat failures. It is hoped that the information about the failure mechanisms of BTF supplied in this course will help to put plant engineers and chemists on the right track. The major goal of this course is the avoidance of repeat BTF. This fourth lesson is focused on hydrogen damage of water-touched tubes in conventional boilers and in the high-pressure evaporators of heat recovery steam generators. (orig.)

  4. Boiler and HRSG tube failures. Lesson 5. Caustic gouging

    Energy Technology Data Exchange (ETDEWEB)

    Dooley, Barry R.; Bursik, Albert

    2010-03-15

    University 101 courses are typically designed to help incoming first-year undergraduate students to adjust to the university, develop a better understanding of the college environment, and acquire essential academic success skills. Why are we offering a special Boiler and HRSG Tube Failures PPChem 101? The answer is simple, yet very conclusive: - There is a lack of knowledge on the identification of tube failure mechanisms and for the implementation of adequate counteractions in many power plants, particularly at industrial power and steam generators. - There is a lack of knowledge to prevent repeat tube failures. The vast majority of BTF/HTF have been, and continue to be, repeat failures. It is hoped that the information about the failure mechanisms of BTF supplied in this course will help to put plant engineers and chemists on the right track. The major goal of this course is the avoidance of repeat BTF. This fifth lesson is focused on caustic gouging of water-touched tubes in conventional boilers and in the high-pressure evaporators of heat recovery steam generators. (orig.)

  5. Influence of boiler load on water tubes burnout

    Energy Technology Data Exchange (ETDEWEB)

    Said, S.A.M.; Habib, M.A.; Badr, H.M.; Mansour, R. [King Fahd Univ. of Petroleum and Minerals, Dhahran (Saudi Arabia). Dept. of Mechanical Engineering

    2009-07-01

    The influence of boiler loads on water tube burnout was investigated. The in-service boiler had 2 burners at different levels located in the front of the burner's wall. Homogenous-flow and separated-flow models were designed to simulate the water circulation and combustion processes inside the boiler tubes. Heat flux calculations were derived by solving the conservation of mass, momentum, and energy equations and species concentration as well as by solving turbulence, reaction rate, and radiation model equations. Results of the study showed that heat flux during full loads ranged from close to 0 to 270 kW/m2. The right side screen wall of the burner exhibited higher heat flux values in the middle region of the wall where large areas were subjected to heat flux close to a maximum of 270 kW/m2. Results also included reductions in heat flux values at partial loads. Maximum values were reduced from 270 kW/m2 ato 230 kW/m2 at 75 per cent capacity and 200 kW/m2 at 60 per cent capacity. The rate of steam generation increased from 0.1 kg/s to 0.153 kg/s when the distance from the burner wall increased from 2 meters to 12 meters. 10 refs., 10 figs.

  6. Hydrogen attack evaluation of boiler tube using ultrasonic wave

    International Nuclear Information System (INIS)

    Won, Soon Ho; Hyun, Yang Ki; Lee, Jong O; Cho, Kyung Shik; Lee, Jae Do

    2001-01-01

    The presence of hydrogen in industrial plants is a source of damage. Hydrogen attack is one such form of degradation and often causing large tube ruptures that necessitate an immediate shutdown. Hydrogen attack may reduce the fracture toughness as well as the strength of steels. This reduction is caused partially by the presence of cavities and microcracks at the grain boundaries. In the past several techniques have been used with limited results. This paper describes the application of an ultrasonic velocity, attenuation and backscatter techniques for detecting the presence of hydrogen damage in utility boiler tubes. Ultrasonic tests showed a decrease in wave velocity and an increase in attenuation. Such results demonstrate the potential for ultrasonic nondestructive testing to quantify damage. Based on this study, recommendations are that both velocity and attenuation be used to detect hydrogen attack in steels.

  7. A study on the leak monitoring of boiler tube in power plants

    International Nuclear Information System (INIS)

    Lee, Sang Guk

    2002-01-01

    Main equipment of thermal power plant, such as boiler and turbine, are designed and manufactured by domestic techniques. But the special equipments monitoring the operation status of these main facilities are still dependent upon foreign technology. Therefore, so as to develop boiler tube leak detection system, we performed studying on manufacturing, installation in site, Acoustic Emission (AE) signal analysis and discrimination etc. As result of studying on boiler tube leak detection using AE, we conformed that diagnosis for boiler tube and computerized their trend management is possible, and also it is expected to contribute to safe operation of power plant facilities

  8. Evaluation of iron aluminide weld overlays for erosion - corrosion resistant boiler tube coatings in low NO{sub x} boilers

    Energy Technology Data Exchange (ETDEWEB)

    DuPont, J.N.; Banovic, S.W.; Marder, A.R. [Lehigh Univ., Bethlehem, PA (United States)

    1996-08-01

    Low NOx burners are being installed in many fossil fired power plants in order to comply with new Clean Air Regulations. Due to the operating characteristics of these burners, boiler tube sulfidation corrosion is often enhanced and premature tube failures can occur. Failures due to oxidation and solid particle erosion are also a concern. A program was initiated in early 1996 to evaluate the use of iron aluminide weld overlays for erosion/corrosion protection of boiler tubes in Low NOx boilers. Composite iron/aluminum wires will be used with the Gas Metal Arc Welding (GMAW) process to prepare overlays on boiler tubes steels with aluminum contents from 8 to 16wt%. The weldability of the composite wires will be evaluated as a function of chemical composition and welding parameters. The effect of overlay composition on corrosion (oxidation and sulfidation) and solid particle erosion will also be evaluated. The laboratory studies will be complemented by field exposures of both iron aluminide weld overlays and co-extruded tubing under actual boiler conditions.

  9. Composite tube cracking in kraft recovery boilers: A state-of-the-art review

    Energy Technology Data Exchange (ETDEWEB)

    Singbeil, D.L.; Prescott, R. [Pulp and Paper Research Inst. of Canada, Vancouver, British Columbia (Canada); Keiser, J.R.; Swindeman, R.W. [Oak Ridge National Lab., TN (United States)

    1997-07-01

    Beginning in the mid-1960s, increasing energy costs in Finland and Sweden made energy recovery more critical to the cost-effective operation of a kraft pulp mill. Boiler designers responded to this need by raising the steam operating pressure, but almost immediately the wall tubes in these new boilers began to corrode rapidly. Test panels installed in the walls of the most severely corroding boiler identified austenitic stainless steel as sufficiently resistant to the new corrosive conditions, and discussions with Sandvik AB, a Swedish tube manufacturer, led to the suggestion that coextruded tubes be used for water wall service in kraft recovery boilers. Replacement of carbon steel by coextruded tubes has solved most of the corrosion problems experienced by carbon steel wall tubes, however, these tubes have not been problem-free. Beginning in early 1995, a multidisciplinary research program funded by the US Department of Energy was established to investigate the cause of cracking in coextruded tubes and to develop improved materials for use in water walls and floors of kraft recovery boilers. One portion of that program, a state-of-the-art review of public- and private-domain documents related to coextruded tube cracking in kraft recovery boilers is reported here. Sources of information that were consulted for this review include the following: tube manufacturers, boiler manufacturers, public-domain literature, companies operating kraft recovery boilers, consultants and failure analysis laboratories, and failure analyses conducted specifically for this project. Much of the information contained in this report involves cracking problems experienced in recovery boiler floors and those aspects of spout and air-port-opening cracking not readily attributable to thermal fatigue. 61 refs.

  10. Fire-Side Corrosion: A Case Study of Failed Tubes of a Fossil Fuel Boiler

    Directory of Open Access Journals (Sweden)

    Majid Asnavandi

    2017-01-01

    Full Text Available The failures of superheater and reheater boiler tubes operating in a power plant utilizing natural gas or mazut as a fuel have been analysed and the fire-side corrosion has been suggested as the main reason for the failure in boiler tubes. The tubes have been provided by a fossil fuel power plant in Iran and optical and electron microscopy investigations have been performed on the tubes as well as the corrosion products on their surfaces. The results showed that the thickness of the failed tubes is not uniform which suggests that fire-side corrosion has happened on the tubes. Fire-side corrosion is caused by the reaction of combustion products with oxide layers on the tube surface resulting in metal loss and consequently tubes fracture. However, the tubes corrosion behaviour did not follow the conventional models of the fire-side corrosion. Given that, using the corrosion monitoring techniques for these boiler tubes seems essential. As a result, the thickness of the boiler tubes in different parts of the boiler has been recorded and critical points are selected accordingly. Such critical points are selected for installation of corrosion monitoring probes.

  11. The use of laser-induced plasma spectroscopy technique for the characterization of boiler tubes

    International Nuclear Information System (INIS)

    Nicolas, G.; Mateo, M.P.; Yanez, A.

    2007-01-01

    The present work focuses on the characterization of boiler tube walls using laser-induced plasma spectroscopy technique with visual inspection by optical and scanning electron microscopy of the cross-sections of these tubes. In a watertube boiler, water runs through tubes that are surrounded by a heating source. As a result, the water is heated to very high temperatures, causing accumulation of deposits on the inside surfaces of the tubes. These deposits play an important role in the efficiency of the boiler tube because they produce a reduction of the boiler heat rate and an increase in the number of tube failures. The objectives are to determine the thickness and arrangement of deposits located on the highest heat area of the boiler and compare them with tube parts where the heat flux is lower. The major deposits found were copper and magnetite. These deposits come mainly from the boiler feedwater and from the reaction between iron and water, and they do not form on the tube walls at a uniform rate over time. Their amount depends on the areas where they are collected. A Nd:YAG laser operating at 355 nm has been used to perform laser-induced plasma spectra and depth profiles of the deposits

  12. The use of laser-induced plasma spectroscopy technique for the characterization of boiler tubes

    Science.gov (United States)

    Nicolas, G.; Mateo, M. P.; Yañez, A.

    2007-12-01

    The present work focuses on the characterization of boiler tube walls using laser-induced plasma spectroscopy technique with visual inspection by optical and scanning electron microscopy of the cross-sections of these tubes. In a watertube boiler, water runs through tubes that are surrounded by a heating source. As a result, the water is heated to very high temperatures, causing accumulation of deposits on the inside surfaces of the tubes. These deposits play an important role in the efficiency of the boiler tube because they produce a reduction of the boiler heat rate and an increase in the number of tube failures. The objectives are to determine the thickness and arrangement of deposits located on the highest heat area of the boiler and compare them with tube parts where the heat flux is lower. The major deposits found were copper and magnetite. These deposits come mainly from the boiler feedwater and from the reaction between iron and water, and they do not form on the tube walls at a uniform rate over time. Their amount depends on the areas where they are collected. A Nd:YAG laser operating at 355 nm has been used to perform laser-induced plasma spectra and depth profiles of the deposits.

  13. Identification of boiler tube leak in PHWR by measuring short lived radioisotope Iodine-134 in boiler water using gamma spectrometric techniques

    International Nuclear Information System (INIS)

    Pal, P.K.; Bohra, R.C.

    2015-01-01

    The boiler tube made up of Monel-400 of RAPS-2 has failed on few occasions. Due to the failure of boiler tube, the active heavy water enters into boiler and feed water leading to contamination of radioactivity in secondary water circuit. The identification of boiler tube failure was done by measuring gamma ray activity of Iodine-134 in the boiler water with sample using gamma spectrometry with high purity germanium detector. In order to increase the sensitivity of the method 5 liters of Boiler water sample was passed through a plastic column containing 40 ml of anion resin and 10 ml of activated charcoal to capture the isotopes of Iodine in the anionic form and molecular form. Samples were collected from all 8 Boilers of RAPS-2. The activity of 134 I was shown only by Boiler - 5. No other boilers showed any activity of 134 I. This indicated that Boiler - 5 had leaky tubes. The leaky hairpin of boiler - 5 was identified by measuring Tritium and IP in the riser and down comer of all 10 HXs. On the basis of Tritium and IP result, HX-7 was identified as leaky hairpin. (author)

  14. Life Management Technique of Thermal Fatigue for SMST Boiler Tube at Different Heating Zone Using Smithy Furnace

    OpenAIRE

    Shekhar Pal,; Pradeep Suman

    2014-01-01

    This paper highlights on the evaluation of thermal fatigue failure for SMST (Salzgitter Mannesmann strain less boiler tube) DMV 304 HCu boiler tube using life management technique by using of smithy furnace. Boiler tubes are highly affected by operating conditions like, high temperature and high pressure. So it needs periodic checking for the purpose of safety and health assessment of the plant. So using this technique we can identify the degradation of tubes at microstructure...

  15. Fire-Side Corrosion: A Case Study of Failed Tubes of a Fossil Fuel Boiler

    OpenAIRE

    Asnavandi, Majid; Kahram, Mohaddeseh; Rezaei, Milad; Rezakhani, Davar

    2017-01-01

    The failures of superheater and reheater boiler tubes operating in a power plant utilizing natural gas or mazut as a fuel have been analysed and the fire-side corrosion has been suggested as the main reason for the failure in boiler tubes. The tubes have been provided by a fossil fuel power plant in Iran and optical and electron microscopy investigations have been performed on the tubes as well as the corrosion products on their surfaces. The results showed that the thickness of the failed tu...

  16. Hydrogen embrittlement corrosion failure of water wall tubes in large power station boilers

    International Nuclear Information System (INIS)

    Mathur, P.K.

    1981-01-01

    In the present paper, causes and mechanism of hydrogen embrittlement failure of water wall tubes in high pressure boilers have been discussed. A low pH boiler water environment, produced as a result of condenser leakage or some other type of system contamination and presence of internal metal oxide deposits, which permit boiler water solids to concentrate during the process of steam generation, have been ascribed to accelerate the formation of local corrosion cells conducive for acid attack resulting in hydrogen damage failure of water wall tubes. (author)

  17. Application and verification of cold air velocity technique for solving tube ash erosion problem in PC boilers

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Kisoo; Jeong, Kwon Seok [Korea Southern Power Corporation, Gimhae (Korea, Republic of)

    2012-06-15

    Fly ash erosion is a leading cause of boiler tube failure in PC boilers. Therefore, shields or baffle plates are installed in specific areas to mitigate fly ash erosion and prevent boiler tube failure. However, the tube failure problems caused by fly ash erosion cannot be eliminated with this solution alone, because each PC boiler has a different flue gas flow pattern and erosion can become severe in unexpected zones. This problem is caused by an asymmetric internal flow velocity and local growth of the flue gas velocity. For these reasons, clearly defining the flow pattern in PC boilers is important for solving the problem of tube failure caused by fly ash erosion. For this purpose, the cold air velocity technique (CAVT) can be applied to the fly ash erosion problem. In this study, CAVT was carried out on the Hadong 2 PC boiler and the feasibility of application of CAVT to conventional PC boilers was validated.

  18. Application and verification of cold air velocity technique for solving tube ash erosion problem in PC boilers

    International Nuclear Information System (INIS)

    Yoo, Kisoo; Jeong, Kwon Seok

    2012-01-01

    Fly ash erosion is a leading cause of boiler tube failure in PC boilers. Therefore, shields or baffle plates are installed in specific areas to mitigate fly ash erosion and prevent boiler tube failure. However, the tube failure problems caused by fly ash erosion cannot be eliminated with this solution alone, because each PC boiler has a different flue gas flow pattern and erosion can become severe in unexpected zones. This problem is caused by an asymmetric internal flow velocity and local growth of the flue gas velocity. For these reasons, clearly defining the flow pattern in PC boilers is important for solving the problem of tube failure caused by fly ash erosion. For this purpose, the cold air velocity technique (CAVT) can be applied to the fly ash erosion problem. In this study, CAVT was carried out on the Hadong 2 PC boiler and the feasibility of application of CAVT to conventional PC boilers was validated

  19. Leak detection evaluation of boiler tube for power plant using acoustic emission

    International Nuclear Information System (INIS)

    Lee, Sang Guk; Chung, Min Hwa; Nam, Ki Woo

    2001-01-01

    Main equipment of thermal power plant, such as boiler and turbine, are designed and manufactured by domestic techniques. And also the automatic control facilities controlling the main equipment are at the applying step of the localization. and many parts of BOP(Balance Of Plant) equipment are utilizing, localized. But because the special equipment monitoring the operation status of the main facilities such as boiler and turbine are still dependent upon foreign technology and especially boiler tube leak detection system is under the initial step of first application to newly-constructed plants and the manufacturing and application are done by foreign techniques mostly, fast localization development is required. Therefore, so as to study and develop boiler tube leak detection system, we performed studying on manufacturing, installation in site, acoustic emission(AE) signal analysis and discrimination etc. As a result of studying on boiler tube leak detection using AE, we conformed that diagnosis for boiler tube and computerized their trend management is possible, and also it is expected to contribute to safe operation of power generation facilities.

  20. Fracture analysis of tube boiler for physical explosion accident.

    Science.gov (United States)

    Kim, Eui Soo

    2017-09-01

    Material and failure analysis techniques are key tools for determining causation in case of explosive and bursting accident result from material and process defect of product in the field of forensic science. The boiler rupture generated by defect of the welding division, corrosion, overheating and degradation of the material have devastating power. If weak division of boiler burner is fractured by internal pressure, saturated vapor and water is vaporized suddenly. At that time, volume of the saturated vapor and water increases up to thousands of volume. This failure of boiler burner can lead to a fatal disaster. In order to prevent an explosion and of the boiler, it is critical to introduce a systematic investigation and prevention measures in advance. In this research, the cause of boiler failure is investigated through forensic engineering method. Specifically, the failure mechanism will be identified by fractography using scanning electron microscopes (SEM) and Optical Microscopes (OM) and mechanical characterizations. This paper presents a failure analysis of household welding joints for the water tank of a household boiler burner. Visual inspection was performed to find out the characteristics of the fracture of the as-received material. Also, the micro-structural changes such as grain growth and carbide coarsening were examined by optical microscope. Detailed studies of fracture surfaces were made to find out the crack propagation on the weld joint of a boiler burner. It was concluded that the rupture may be caused by overheating induced by insufficient water on the boiler, and it could be accelerated by the metal temperature increase. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. ANALISA KEHILANGAN ENERGI PADA FIRE TUBE BOILER KAPASITAS 10 TON

    Directory of Open Access Journals (Sweden)

    Aditio Primayudi Aji Nugroho

    2015-06-01

    Full Text Available Tujuan dari penulisan ini adalah menghitung kinerja boiler dengan mengetahui kerugian energi pada saat produksi steam. Analisa teknis pada boiler sangat diperlukan, sebagai upaya peningkatan efisiensi dan mengetahui banyaknya energi yang terbuang sebagai kerugian. Faktorfaktor penyebab kehilangan panas/heat loss terbesar pada boiler antara lain : “kehilangan panas akibat gas buang kering, kandungan steam dalam gas buang, kandungan air dalam bahan bakar, kandungan air dalam suplai udara dan lain-lain”.Kehilangan panas/heat loss atau juga bisa disebut kehilangan energi merupakan salah satu faktor penting yang sangat berpengaruh dalam mengidentifikasi efisiensi pada boiler.Untuk itu dilakukan studi analisa dengan perhitungan kehilangan panas dengan tujuan untuk mengetahui besarnya penurunan performance dan penyebab dari penurunan performance. Berdasarkan data dan analisa metode direct diketahui penurunan sebesar 21% pada kondisi normal (operasi 79% dan dari hasil perhitungan kehilangan panas indirect sebesar 16.68% efisiensi boiler sebesar 83.32% maka dari itu adanya kehilangan panas, perlu adanya perbaikan dalam control pengaturan bahan bakar dan udara yang masuk secara optimum dengan cara menggunakan Oxygen Trim Control yang berfungsi untuk mengukur konsentrasi oksigen pada cerobong dan secara otomatis mengatur oksigen pada udara yang masuk burner sehingga dihasilkan pembakaran dengan efisiensi yang optimal.dan dengan menggunakan economizer pada pemanasan awal suhu air umpan dapat menaikan efisiensi boiler.

  2. The mechanical design and validation of the helical tube boilers for Hartlepool and Heysham AGR stations

    International Nuclear Information System (INIS)

    Skinner, V.R.

    1983-01-01

    The 32 helically coiled once-through boiler units at Hartlepool and Heysham represent a major advance in the technologies of boiler design, manufacture and site construction. They are particularly complex in that they incorporate integral reheaters; they employ three different tubing materials and five different structural materials, each with operating temperature limitations; and they must fit compactly into pods in the reactor pressure vessel walls. A general description of the boilers is followed by a review of external factors which influenced the mechanical design and validation programme over 15 years. Against this background selected components are discussed in detail in terms of particular loading conditions and stress analysis. (author)

  3. Innovative coupling of cogeneration units with fire tube boilers: thermo-fluid dynamics of the fire tubes

    Science.gov (United States)

    Cioccolanti, L.; Arteconi, A.; Bartolini, C. M.; Polonara, F.

    2017-11-01

    Nowadays the thermal energy demand in the industrial sector is usually satisfied by means of fire tube boilers while electricity is supplied from the grid. Alternatively cogeneration units could be adopted for thermal and electrical energy self-production, whilst installing boilers only as back-up units. However, even when cogeneration is profitable, it is not widespread because industries are usually unwilling to accept cogeneration plants for reliability and high investment costs issues. In this work a system aimed at overcoming the above mentioned market difficulties is proposed. It consists of an innovative coupling of a combined heat and power unit with a modified fire tube boiler. In particular, a CFD analysis was carried out by the authors in order to address the most critical aspects related with the coupling of the two systems. More precisely, the following aspects were evaluated in detail: (i) pressure losses of the exhausts going from the prime mover to the boiler due to the sudden cross-section area variations; (ii) thermal power recoverable from the exhausts in the tubes of the boiler; (iii) dependence of the system on the final users’ specification.

  4. Researching the Performance of Dual-Chamber Fire-Tube Boiler Furnace

    Directory of Open Access Journals (Sweden)

    Khaustov Sergei

    2015-01-01

    Full Text Available Autonomous heating systems equipped with fire-tube or shell boilers show high effectiveness, consistent performance and great technical parameters. But there is a significant limitation of its thermal productivity due to the complexity of durable large diameter fire-tube bottoms implementation. Optimization of combustion aerodynamics can be the way to expand the fire-tube boilers performance limit. In this case lots of problems connected with reducing emissions of toxic substances, providing of burning stability, local heat stresses and aerodynamic resistances should be solved. To resolve the indicated problems, a modified model of dual-chamber fire-tube boiler furnace is proposed. The performance of suggested flame-tube was simulated using the proven computer-aided engineering software ANSYS Multiphysics. Results display proposed flame tube completely filled with moving medium without stagnant zones. Turbulent vortical combustion is observed even with the straight-through fuel supply. Active flue gas recirculation in suggested dual-chamber furnace reduces emissions of pollutants. Diminution of wall heat fluxes allows boiler operation at lower water treatment costs.

  5. Investigation into Cause of High Temperature Failure of Boiler Superheater Tube

    Science.gov (United States)

    Ghosh, D.; Ray, S.; Roy, H.; Shukla, A. K.

    2015-04-01

    The failure of the boiler tubes occur due to various reasons like creep, fatigue, corrosion and erosion. This paper highlights a case study of typical premature failure of a final superheater tube of 210 MW thermal power plant boiler. Visual examination, dimensional measurement, chemical analysis, oxide scale thickness measurement, microstructural examination are conducted as part of the investigations. Apart from these investigations, sulfur print, Energy Dispersive spectroscopy (EDS) and X ray diffraction analysis (XRD) are also conducted to ascertain the probable cause of failure of final super heater tube. Finally it has been concluded that the premature failure of the super heater tube can be attributed to the combination of localized high tube metal temperature and loss of metal from the outer surface due to high temperature corrosion. The corrective actions have also been suggested to avoid this type of failure in near future.

  6. Sensing system for detection and control of deposition on pendant tubes in recovery and power boilers

    Science.gov (United States)

    Kychakoff, George [Maple Valley, WA; Afromowitz, Martin A [Mercer Island, WA; Hogle, Richard E [Olympia, WA

    2008-10-14

    A system for detection and control of deposition on pendant tubes in recovery and power boilers includes one or more deposit monitoring sensors operating in infrared regions of about 4 or 8.7 microns and directly producing images of the interior of the boiler, or producing feeding signals to a data processing system for information to enable a distributed control system by which the boilers are operated to operate said boilers more efficiently. The data processing system includes an image pre-processing circuit in which a 2-D image formed by the video data input is captured, and includes a low pass filter for performing noise filtering of said video input. It also includes an image compensation system for array compensation to correct for pixel variation and dead cells, etc., and for correcting geometric distortion. An image segmentation module receives a cleaned image from the image pre-processing circuit for separating the image of the recovery boiler interior into background, pendant tubes, and deposition. It also accomplishes thresholding/clustering on gray scale/texture and makes morphological transforms to smooth regions, and identifies regions by connected components. An image-understanding unit receives a segmented image sent from the image segmentation module and matches derived regions to a 3-D model of said boiler. It derives a 3-D structure the deposition on pendant tubes in the boiler and provides the information about deposits to the plant distributed control system for more efficient operation of the plant pendant tube cleaning and operating systems.

  7. Estimation of residual life of boiler tubes using steamside oxide scale thickness

    International Nuclear Information System (INIS)

    Vikrant, K.S.N.; Ramareddy, G.V.; Pavan, A.H.V.; Singh, Kulvir

    2013-01-01

    In thermal power plants, remaining-life-estimation of boiler tubes is required at regular intervals for a safer and a better functionality of boilers. In this paper, a new method is proposed for the residual life estimation of service exposed boiler tubes using Non-Destructive Ultrasonic Oxide scale thickness measurements, average metal temperature and creep master curve. While steady state conduction heat transfer equations are solved to calculate the average metal temperature, creep master curve is generated from short term stress rupture data of rupture life less than 5000 h on a virgin material. In the present study, the residual life of T22 (2.25Cr-1Mo) service exposed Platen Superheater tube is estimated using two master creep curves, i.e. Larson-Miller Parametric (LMP) method of standard ASME T22 creep data and Wilshire approach of short term stress rupture data of T22. As the residual life is calculated from fundamental conduction heat transfer theory and creep rupture data, the proposed method can be applied for different grades of boiler materials. -- Highlights: ► Residual life is calculated from non-destructive oxide scale thickness, creep master curve and average metal temperature. ► A new method is proposed for calculating residual life using above parameters and from conduction heat transfer principles. ► The method can be applied to different boiler grades for estimating residual life and hence the method is generic

  8. Aspects of high temperature corrosion of boiler tubes

    Energy Technology Data Exchange (ETDEWEB)

    Spiegel, M.; Bendick, W. [Salzgitter-Mannesmann-Forschung GmbH, Duisburg (Germany)

    2008-07-01

    The development of new boiler steels for power generation has to consider significant creep strength as well as oxidation and corrosion resistance. High temperature corrosion of boiler materials concerns steam oxidation as well as fireside corrosion of parts, in contact with the flue gas. It will be shown that depending on the quality of the fuel, especially chlorine and sulphur are responsible for most of the fireside corrosion problems. Corrosion mechanisms will be presented for flue gas induced corrosion (HCl) and deposit induced corrosion (chlorides and sulfates). Especially for the 700 C technology, deposit induced corrosion issues have to be considered and the mechanisms of corrosion by molten sulfates 'Hot Corrosion' will be explained. Finally, an overview will be given on the selection of suitable materials in order to minimise corrosion relates failures. (orig.)

  9. Study of microstructural changes in boiler tubes and usage of time approach for determining of tube's failure

    International Nuclear Information System (INIS)

    Hemasi Taherabadi, L.; Raeiatpour, M.; Mehdizadeh, M.

    2001-01-01

    Operation condition of boilers such as corrosive media, high temperature and pressure has a pronounced effect on quality and performance of its components. Among these, the effect of temperature in microstructure and degradation of mechanical properties of boiler tubes is of most importance. Change in dimension, morphology, chemical composition and carbide spacing are the most important microstructural changes. Methods of study of such changes (through the investigation of composition, carbide spacing and thermal softening) are pointed in this article. Then, a number of failed super-heater tubes of a power plant were microlithography examined. Remaining life of tubes could be estimated by comparison of the results of metallographic and replication tests with microstructural standards

  10. Overheating failure of superheater suspension tubes of a captive thermal power plant boiler

    International Nuclear Information System (INIS)

    Bhattacharya, Sova; Amir, Q.M.; Kannan, C.; Mahapatra, S.B.

    2000-01-01

    Failure of boiler tubes is the foremost cause of forced boiler outages. One of the predominant failure mechanism of boiler tubes is the stress rupture failure in the form of either short term overheating or long term overheating which are normally encountered in superheater and reheater sections working in the creep range. The strength of the boiler tube depends on the stress level as well on the temperature of exposure in the creep range. An increase in either can reduce the time to rupture. Time at the exposure temperature is an important factor based on which the failures are categorised as either short term or long term. Though there is no established time duration criteria demarcating the short or long term stress rupture failures, depending on the various manifestations on the failed samples, one can categorise the failure. This paper addresses one such stress rupture failure in the superheater section of a captive thermal power plant of a refinery. Multiple failures on the suspension coil of a superheater section was investigated for the cause of failure. Laboratory investigation of the failed sample involved visual inspection, dimensional measurements, chemical analysis of internal deposits and microstructural study. On the basis of these, the failure was attributed to deposition of trisodium phosphate carried over by the feed water into the superheater section resulting in chokage and increase in local operating hoop stresses of the tube. The ultimate failure was thus categorised as long term overheating failure. (author)

  11. Utilization of coal-water fuels in fire-tube boilers

    International Nuclear Information System (INIS)

    Sommer, T.M.; Melick, T.A.

    1991-01-01

    The Energy and Environmental Research Corporation (EER), in cooperation with the University of Alabama and Jim Walter Resources, has been awarded a DOE contract to retrofit an existing fire-tube boiler with a coal-water slurry firing system. Recognizing that combustion efficiency is the principle concern when firing slurry in fire-tube boilers, EER has focused the program on innovative approaches for improving carbon burnout without major modifications to the boiler. This paper reports on the program which consists of five tasks. Task 1 provides for the design and retrofit of the host boiler to fire coal-water slurry. Task 2 is a series of optimization tests that will determine the effects of adjustable parameters on boiler performance. Task 3 will perform about 1000 hours of proof-of-concept system tests. Task 4 will be a comprehensive review of the test data in order to evaluate the economics of slurry conversions. Task 5 will be the decommissioning of the test facility if required

  12. Analysis of Boiler Operational Variables Prior to Tube Leakage Fault by Artificial Intelligent System

    Directory of Open Access Journals (Sweden)

    Al-Kayiem Hussain H.

    2014-07-01

    Full Text Available Steam boilers are considered as a core of any steam power plant. Boilers are subjected to various types of trips leading to shut down of the entire plant. The tube leakage is the worse among the common boiler faults, where the shutdown period lasts for around four to five days. This paper describes the rules of the Artificial Intelligent Systems to diagnosis the boiler variables prior to tube leakage occurrence. An Intelligent system based on Artificial Neural Network was designed and coded in MATLAB environment. The ANN was trained and validated using real site data acquired from coal fired power plant in Malaysia. Ninety three boiler operational variables were identified for the present investigation based on the plant operator experience. Various neural networks topology combinations were investigated. The results showed that the NN with two hidden layers performed better than one hidden layer using Levenberg-Maquardt training algorithm. Moreover, it was noticed that hyperbolic tangent function for input and output nodes performed better than other activation function types.

  13. Numerical simulation of a 374 tons/h water-tube steam boiler following a feedwater line break

    International Nuclear Information System (INIS)

    Deghal Cheridi, Amina Lyria; Chaker, Abla; Loubar, Ahcène

    2016-01-01

    Highlights: • We simulate the behavior of a steam boiler during feed-water line break accident. • To perform accident analysis of the steam boiler, Relap5/Mod3.2 system code is used. • A Relap5 model of the boiler is developed and qualified at the steady state level. • A good agreement between Relap5 results and available experimental data. • The Relap5 model predicts well the main transient features of the boiler. - Abstract: To ensure the operational safety of an industrial water-tube steam boiler it is very important to assess various accident scenarios in real plant working conditions. One of the most challenging scenarios is the loss of feedwater to the steam boiler. In this paper, a simulation of the behavior of an industrial water-tube radiant steam boiler during feedwater line break accident is discussed. The simulation is carried out using the RELAP5 system code. The steam boiler is installed in an Algerian natural gas liquefaction complex. The simulation shows the capabilities of RELAP5 system code in predicting the behavior of the steam boiler at both steady state and transient working conditions. From another side, the behavior of the steam boiler following the accident shows how the control system can successfully mitigate the effects and consequences of such accident and how the evaporator tubes can undergo a severe damage due to an uncontrolled increase of the wall temperature in case of failure of this system.

  14. Modelling of thermal behaviour of iron oxide layers on boiler tubes

    Science.gov (United States)

    Angelo, J. D.; Bennecer, A.; Kaczmarczyk, S.; Picton, P.

    2016-05-01

    Slender boiler tubes are subject to localised swelling when they are expose to excessive heat. The latter is due to the formation of an oxide layer, which acts as an insulation barrier. This excessive heat can lead to microstructural changes in the material that would reduce the mechanical strength and would eventually lead to critical and catastrophic failure. Detecting such creep damage remains a formidable challenge for boiler operators. It involves a costly process of shutting down the plant, performing electromagnetic and ultrasonic non-destructive inspection, repairing or replacing damaged tubes and finally restarting the plant to resume its service. This research explores through a model developed using a finite element computer simulation platform the thermal behaviour of slender tubes under constant temperature exceeding 723 °K. Our simulation results demonstrate that hematite layers up to 15 μm thickness inside the tubes do not act as insulation. They clearly show the process of long term overheating on the outside of boiler tubes which in turn leads to initiation of flaws.

  15. Fire-tube boiler optimization criteria and efficiency indicators rational values defining

    Science.gov (United States)

    Batrakov, P. A.; Mikhailov, A. G.; Ignatov, V. Yu

    2018-01-01

    Technical and economic calculations problems solving with the aim of identifying the opportunity to recommend the project for industrial implementation are represented in the paper. One of the main determining factors impacting boiler energy efficiency is the exhaust gases temperature, as well as the furnace volume thermal stress. Fire-tube boilers with different types of furnaces are considered in the study. The fullest analysis of the boiler performance thermal and technical indicators for the following engineering problem: Q=idem, M=idem and evaluation according to η, B is presented. The furnace with the finned ellipse profile application results in the fuel consumption decrease due to a more efficient heat exchange surface of the furnace compared to other examined ones.

  16. Creep-Rupture Behavior of Ni-Based Alloy Tube Bends for A-USC Boilers

    Science.gov (United States)

    Shingledecker, John

    Advanced ultrasupercritical (A-USC) boiler designs will require the use of nickel-based alloys for superheaters and reheaters and thus tube bending will be required. The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code Section II PG-19 limits the amount of cold-strain for boiler tube bends for austenitic materials. In this summary and analysis of research conducted to date, a number of candidate nickel-based A-USC alloys were evaluated. These alloys include alloy 230, alloy 617, and Inconel 740/740H. Uniaxial creep and novel structural tests and corresponding post-test analysis, which included physical measurements, simplified analytical analysis, and detailed microscopy, showed that different damage mechanisms may operate based on test conditions, alloy, and cold-strain levels. Overall, creep strength and ductility were reduced in all the alloys, but the degree of degradation varied substantially. The results support the current cold-strain limits now incorporated in ASME for these alloys for long-term A-USC boiler service.

  17. Early tube leak detection system for steam boiler at KEV power plant

    Directory of Open Access Journals (Sweden)

    Ismail Firas B.

    2016-01-01

    Full Text Available Tube leakage in boilers has been a major contribution to trips which eventually leads to power plant shut downs. Training of network and developing artificial neural network (ANN models are essential in fault detection in critically large systems. This research focusses on the ANN modelling through training and validation of real data acquired from a sub-critical boiler unit. The artificial neural network (ANN was used to develop a compatible model and to evaluate the working properties and behaviour of boiler. The training and validation of real data has been applied using the feed-forward with back-propagation (BP. The right combination of number of neurons, number of hidden layers, training algorithms and training functions was run to achieve the best ANN model with lowest error. The ANN was trained and validated using real site data acquired from a coal fired power plant in Malaysia. The results showed that the Neural Network (NN with one hidden layers performed better than two hidden layer using feed-forward back-propagation network. The outcome from this study give us the best ANN model which eventually allows for early detection of boiler tube leakages, and forecast of a trip before the real shutdown. This will eventually reduce shutdowns in power plants.

  18. Iron aluminide weld overlay coatings for boiler tube protection in coal-fired low NOx boilers

    Energy Technology Data Exchange (ETDEWEB)

    Banovic, S.W.; DuPont, J.N.; Marder, A.R. [Lehigh Univ., Bethlehem, PA (United States). Energy Research Center

    1997-12-01

    Iron aluminide weld overlay coatings are currently being considered for enhanced sulfidation resistance in coal-fired low NO{sub x} boilers. The use of these materials is currently limited due to hydrogen cracking susceptibility, which generally increases with an increase in aluminum concentration of the deposit. The overall objective of this program is to attain an optimum aluminum content with good weldability and improved sulfidation resistance with respect to conventional materials presently in use. Research has been initiated using Gas Tungsten Arc Welding (GTAW) in order to achieve this end. Under different sets of GTAW parameters (wire feed speed, current), both single and multiple pass overlays were produced. Characterization of all weldments was conducted using light optical microscopy, scanning electron microscopy, and electron probe microanalysis. Resultant deposits exhibited a wide range of aluminum contents (5--43 wt%). It was found that the GTAW overlays with aluminum contents above {approximately}10 wt% resulted in cracked coatings. Preliminary corrosion experiments of 5 to 10 wt% Al cast alloys in relatively simple H{sub 2}/H{sub 2}S gas mixtures exhibited corrosion rates lower than 304 stainless steel.

  19. Cracking and Corrosion of Composite Tubes in Black Liquor Recovery Boiler Primary Air Ports

    Energy Technology Data Exchange (ETDEWEB)

    Keiser, James R.; Singbeil, Douglas L.; Sarma, Gorti B.; Kish, Joseph R.; Yuan, Jerry; Frederick, Laurie A.; Choudhury, Kimberly A.; Gorog, J. Peter; Jetté, Francois R.; Hubbard, Camden R.; Swindeman, Robert W.; Singh, Prett M.; Maziasz, Phillip J.

    2006-10-01

    Black liquor recovery boilers are an essential part of kraft mills. Their design and operating procedures have changed over time with the goal of providing improved boiler performance. These performance improvements are frequently associated with an increase in heat flux and/or operating temperature with a subsequent increase in the demand on structural materials associated with operation at higher temperatures and/or in more corrosive environments. Improvements in structural materials have therefore been required. In most cases the alternate materials have provided acceptable solutions. However, in some cases the alternate materials have solved the original problem but introduced new issues. This report addresses the performance of materials in the tubes forming primary air port openings and, particularly, the problems associated with use of stainless steel clad carbon steel tubes and the solutions that have been identified.

  20. Some aspects of metallurgical assessment of boiler tubes-Basic principles and case studies

    International Nuclear Information System (INIS)

    Chaudhuri, Satyabrata

    2006-01-01

    Microstructural changes in boiler tubes during prolong operation at high temperature and pressure decrease load bearing capacity limiting their useful lives. When the load bearing capacity falls below a critical level depending on operating parameters and tube geometry, failure occurs. In order to avoid such failures mainly from the view point of economy and safety, this paper describes some basic principles behind remaining life assessment of service exposed components and also a few case studies related to failure of a reheater tube of 1.25Cr-0.5Mo steel, a carbon steel tube and final superheater tubes of 2.25Cr-1Mo steel and remaining creep life assessment of service exposed but unfailed platen superheater and reheater tubes of 2.25Cr-1Mo steel. Sticking of fly ash particles causing reduction in effective tube wall thickness is responsible for failure of reheater tubes. Decarburised metal containing intergranular cracks at the inner surface of the carbon steel tube exhibiting a brittle window fracture is an indicative of hydrogen embrittlement responsible for this failure. In contrast, final superheater tube showed that the failure took place due to short-term overheating. The influence of prolong service revealed that unfailed reheater tubes exhibit higher tensile properties than that of platen superheater tubes. In contrast both the tubes at 50 MPa meet the minimum creep rupture properties when compared with NRIM data. The remaining creep life of platen superheater tube as estimated at 50 MPa and 570 deg. C (1058 o F) is more than 10 years and that of reheater tube at 50 MPa and 580 deg. C (1076 o F) is 9 years

  1. EXPERIMENTAL INVESTIGATION OF NICKEL ALUMINIDE (NI3AL) NANOSTRUCTURED COATED ECONOMISER TUBE IN BOILER

    OpenAIRE

    * Gokulakannan A, Karuppasamy K

    2016-01-01

    Thermal Power Stations all over the world are facing the problem of boiler tube leakage frequently. The consequences of which affects the performance of power plant and huge amount of money loss. Hot corrosion and erosion are recognized as serious problems in coal based power generation plants in India. The maximum number of cause of failure in economizer unit is due to flue gas erosion. The corrosion resistant coatings used conventionally are having some limitations like degradation of the c...

  2. Failure Investigation of Radiant Platen Superheater Tube of Thermal Power Plant Boiler

    Science.gov (United States)

    Ghosh, D.; Ray, S.; Mandal, A.; Roy, H.

    2015-04-01

    This paper highlights a case study of typical premature failure of a radiant platen superheater tube of 210 MW thermal power plant boiler. Visual examination, dimensional measurement and chemical analysis, are conducted as part of the investigations. Apart from these, metallographic analysis and fractography are also conducted to ascertain the probable cause of failure. Finally it has been concluded that the premature failure of the super heater tube can be attributed to localized creep at high temperature. The corrective actions has also been suggested to avoid this type of failure in near future.

  3. Investigations of the Failure in Boilers Economizer Tubes Used in Power Plants

    Science.gov (United States)

    Moakhar, Roozbeh Siavash; Mehdipour, Mehrad; Ghorbani, Mohammad; Mohebali, Milad; Koohbor, Behrad

    2013-09-01

    In this study, failure of a high pressure economizer tube of a boiler used in gas-Mazut combined cycle power plants was studied. Failure analysis of the tube was accomplished by taking into account visual inspection, thickness measurement, and hardness testing as well as microstructural observations using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and x-ray diffraction (XRD). Optical microscopy images indicate that there is no phase transformation during service, and ferrite-pearlite remained. The results of XRD also revealed Iron sulfate (FeSO4) and Iron hydroxide sulfate (FeOH(SO4)) phases formed on the steel surface. A considerable amount of Sulfur was also detected on the outer surface of the tube by EDS analysis. Dew-point corrosion was found to be the principal reason for the failure of the examined tube while it has been left out-of-service.

  4. Surface chemistry interventions to control boiler tube fouling

    International Nuclear Information System (INIS)

    Turner, C.W.; Guzonas, D.A.; Klimas, S.J.

    2000-06-01

    The adsorption of ammonia, morpholine, ethanolamine, and dimethylamine onto the surfaces of colloidal magnetite and hematite was measured at 25 o C. The effect of the adsorption on the surface potential was quantified by measuring the resulting shift in the isoelectric point of the corrosion products and by the direct measurement of the surface interaction force between the corrosion products and Inconel 600. These measurements have served to support the hypothesis that adsorption of amine affects the magnetite deposition rate by lowering the force of repulsion between magnetite and the surface of Inconel 600. The deposition rate of hematite increased as the oxygen concentration increased. A mechanism to account for enhanced deposition rates at high mixture qualities (> 0.35) has been identified and shown to predict behaviour that is consistent with both experimental and plant data. As a result of this investigation, several criteria are proposed to reduce the extent of corrosion product deposition on the tube bundle. Low hematite deposition is favoured by a low concentration of dissolved oxygen, and low magnetite deposition is favoured by choosing an amine for pH control that has little tendency to adsorb onto the surface of magnetite. To minimize adsorption the amine should have a high base strength and a large 'footprint' on the surface of magnetite. To prevent enhanced deposition at high mixture qualities, it is proposed that a modified amine be used that will reduce the surface tension or the elasticity of the steam-water interface or both

  5. Surface chemistry interventions to control boiler tube fouling

    Energy Technology Data Exchange (ETDEWEB)

    Turner, C.W.; Guzonas, D.A.; Klimas, S.J

    2000-06-01

    The adsorption of ammonia, morpholine, ethanolamine, and dimethylamine onto the surfaces of colloidal magnetite and hematite was measured at 25{sup o}C. The effect of the adsorption on the surface potential was quantified by measuring the resulting shift in the isoelectric point of the corrosion products and by the direct measurement of the surface interaction force between the corrosion products and Inconel 600. These measurements have served to support the hypothesis that adsorption of amine affects the magnetite deposition rate by lowering the force of repulsion between magnetite and the surface of Inconel 600. The deposition rate of hematite increased as the oxygen concentration increased. A mechanism to account for enhanced deposition rates at high mixture qualities (> 0.35) has been identified and shown to predict behaviour that is consistent with both experimental and plant data. As a result of this investigation, several criteria are proposed to reduce the extent of corrosion product deposition on the tube bundle. Low hematite deposition is favoured by a low concentration of dissolved oxygen, and low magnetite deposition is favoured by choosing an amine for pH control that has little tendency to adsorb onto the surface of magnetite. To minimize adsorption the amine should have a high base strength and a large 'footprint' on the surface of magnetite. To prevent enhanced deposition at high mixture qualities, it is proposed that a modified amine be used that will reduce the surface tension or the elasticity of the steam-water interface or both.

  6. An advanced maintenance advisory and surveillance system for boiler tubes - AMASS

    Energy Technology Data Exchange (ETDEWEB)

    Tomkins, A.B. [ERA Technology Ltd, Leatherhead (United Kingdom)

    1998-12-31

    In a recently completed European collaborative project, the aim was to address the issue of boiler tube failures and thereby plant availability. The reduction of forced outages due to component failures and the reduction of planned outages for preventative maintenance can both contribute in this respect. It has been possible to assess tube degradation due to erosion, corrosion and overheating through the use of on-line techniques (thin layer activation, corrosion probes and novel temperature sensors) and off-line techniques (cold air velocity measurements, laser shearography and measurements of steam side oxide) which have been developed in the project. These techniques have been demonstrated on an oil fired boiler in Portugal and a coal fired unit in Spain. The output from the monitoring techniques has been integrated in the AMASS maintenance advisory and surveillance system. This is a computerised system comprising a spatial database with add-on tools designed to assess data from individual monitors and to provide the user with information on tube life utilisation rates and the probability of tube failure occurring. A description of the monitoring techniques will be described along with some of the results of demonstrating them in the field. Also an overview of the computerized system and the way in which it works will be given along with examples of how it can be used to assist with preventative maintenance and to help avoid unplanned outages. (orig.) 10 refs.

  7. An advanced maintenance advisory and surveillance system for boiler tubes - AMASS

    Energy Technology Data Exchange (ETDEWEB)

    Tomkins, A B [ERA Technology Ltd, Leatherhead (United Kingdom)

    1999-12-31

    In a recently completed European collaborative project, the aim was to address the issue of boiler tube failures and thereby plant availability. The reduction of forced outages due to component failures and the reduction of planned outages for preventative maintenance can both contribute in this respect. It has been possible to assess tube degradation due to erosion, corrosion and overheating through the use of on-line techniques (thin layer activation, corrosion probes and novel temperature sensors) and off-line techniques (cold air velocity measurements, laser shearography and measurements of steam side oxide) which have been developed in the project. These techniques have been demonstrated on an oil fired boiler in Portugal and a coal fired unit in Spain. The output from the monitoring techniques has been integrated in the AMASS maintenance advisory and surveillance system. This is a computerised system comprising a spatial database with add-on tools designed to assess data from individual monitors and to provide the user with information on tube life utilisation rates and the probability of tube failure occurring. A description of the monitoring techniques will be described along with some of the results of demonstrating them in the field. Also an overview of the computerized system and the way in which it works will be given along with examples of how it can be used to assist with preventative maintenance and to help avoid unplanned outages. (orig.) 10 refs.

  8. Automating data analysis during the inspection of boiler tubes using line scanning thermography

    Science.gov (United States)

    Ley, Obdulia; Momeni, Sepand; Ostroff, Jason; Godinez, Valery

    2012-05-01

    Failures in boiler waterwalls can occur when a relatively small amount of corrosion and loss of metal have been experienced. This study presents our efforts towards the application of Line Scanning Thermography (LST) for the analysis of thinning in boiler waterwall tubing. LST utilizes a line heat source to thermally excite the surface to be inspected and an infrared detector to record the transient surface temperature increase observed due to the presence of voids, thinning or other defects. In waterwall boiler tubes the defects that can be detected using LST correspond to corrosion pitting, hydrogen damage and wall thinning produced by inadequate burner heating or problems with the water chemistry. In this paper we discuss how the LST technique is implemented to determine thickness from the surface temperature data, and we describe our efforts towards developing a semiautomatic analysis tool to speed up the time between scanning, reporting and implementing repairs. We compare the density of data produced by the common techniques used to assess wall thickness and the data produced by LST.

  9. SUS 321 HTB boiler tubing with fire grained internal surface resistant to steam-induced oxidation

    International Nuclear Information System (INIS)

    Kanero, Takahiro; Minami, Yuusuke; Kodera, Toshihide

    1981-01-01

    Considerable amount of scale is produced by high temperature steam on the austenitic stainless steel tubes used for the superheaters and reheaters of large boilers for power generation. The scale of outer layer separates off due to the thermal stress at the time of starting-up and stopping, and causes the blocking of pipes and the erosion of turbine blades. Following the increase of nuclear power generation, large boilers are used for medium load, accordingly it is expected that the troubles like these increase. In this paper, the manufacturing method and the properties of SUS 321 HTB with fine grain internal surface are reported, which was developed to reduce the rate of growth of scale and to prevent the separation of scale. In order to prevent the separation of scale from austenitic stainless steel tubes, the reduction of scale thickness, surface treatment such as chrome plating, the use of alloys with excellent oxidation resistance, the formation of chrome-rich film rapidly, the heat treatment of cold-worked tubes and so on were carried out. The nitrification of SUS 321 H steel brought about two-phase structure of the fine grain internal surface with excellent oxidation resistance and the rest of coarse grains with high creep strength. (Kako, I.)

  10. Chemistry and melting characteristics of fireside deposits taken from boiler tubes in waste incinerators

    International Nuclear Information System (INIS)

    Otsuka, Nobuo

    2011-01-01

    Highlights: → We examine tube deposits taken from boilers of municipal solid waste incinerators. → Literature survey is done on the corrosion mechanism of tube steels. → Chemical analyses, X-ray diffraction, DSC, and corrosion test were conducted. → Melting behavior of salt constituents affected the corrosiveness of the deposits. - Abstract: Twenty-three tube deposits taken from seven heat-recovery boilers of municipal solid waste incinerators were examined by chemical analyses and X-ray diffraction. These deposits were measured by Differential Scanning Calorimeter (DSC) in N 2 to investigate their melting characteristics. Sixteen deposits were used to evaluate their corrosiveness to carbon steel by high-temperature corrosion test conducted at 400 o C for 20 h in 1500 ppm HCl - 300 ppm SO 2 - 7.5%O 2 - 7.5%CO 2 - 20%H 2 O - N 2 . Total heat of endothermic reactions of the deposits taking place between 200 and 400 o C can be related to the corrosion rate of carbon steel at 400 o C. Corrosion initiated at temperatures when the deposits started to melt, became severe when fused salt constituents increased, and alleviated when the majority of the deposits became fused. The corrosion can be interpreted as fused salt corrosion caused by chloride and sulfate salts.

  11. FAILURE ANALYSIS IN TUBING OF AIR PREHEATER OF BOILER FROM A SUGARCANE MILL

    Directory of Open Access Journals (Sweden)

    Joner Oliveira Alves

    2014-10-01

    Full Text Available The increased demand for energy from sugarcane bagasse has made the sugar and alcohol mills search alternatives to reduce maintenance of the boilers, releasing more time to the production. The stainless steel use has become one of the main tools for such reduction. However, specification errors can lead to premature failures. This work reports the factors that led tubes of AISI 409 stainless steel fail after half season when applied in a air preheater of boiler from a sugarcane mill. In such application, the AISI 304 lasts about 15 seasons and the carbon steel about 3. A tube sent by the sugar mill was characterized by wet chemical analysis, optical microscopy and EDS. Results indicated chloride formation on the internal walls of the tube, which combined with the environment, accelerated the corrosion process. The carbon steel showed high lifetime due to a 70% higher thickness. Due to the work condictions is recommended the use of stainless steels with higher corrosion resistance, such as the traditional AISI 304 or the ferritic AISI 444, the last presents better thermal exchange.

  12. Failure Analysis and Magnetic Evaluation of Tertiary Superheater Tube Used in Gas-Fired Boiler

    Science.gov (United States)

    Mohapatra, J. N.; Patil, Sujay; Sah, Rameshwar; Krishna, P. C.; Eswarappa, B.

    2018-02-01

    Failure analysis was carried out on a prematurely failed tertiary superheater tube used in gas-fired boiler. The analysis includes a comparative study of visual examination, chemical composition, hardness and microstructure at failed region, adjacent and far to failure as well as on fresh tube. The chemistry was found matching to the standard specification, whereas the hardness was low in failed tube compared to the fish mouth opening region and the fresh tube. Microscopic examination of failed sample revealed the presence of spheroidal carbides of Cr and Mo predominantly along the grain boundaries. The primary cause of failure is found to be localized heating. Magnetic hysteresis loop (MHL) measurements were carried out to correlate the magnetic parameters with microstructure and mechanical properties to establish a possible non-destructive evaluation (NDE) for health monitoring of the tubes. The coercivity of the MHL showed a very good correlation with microstructure and mechanical properties deterioration enabling a possible NDE technique for the health monitoring of the tubes.

  13. Modificaciones en las calderas igneotubulares cubanas // Modifications in the Cuban boilers of fire tube

    Directory of Open Access Journals (Sweden)

    I. Pérez Mallea

    1998-01-01

    Full Text Available El objetivo de este trabajo es optimizar y diseñar las calderas igneotubulares nacionales, incluyendo las de inversión de llama yagua caliente. Con este fin se creo un software como soporte científico técnico que permite realizar los diferentes cálculosverificativos a través de los cuales se optimiza._________________________________________________________________________Abstract .The objective of this work is the optimizing and designing of the Cuban boilers of fire tube, including those of inverting offlame and hot water. A software have been developed as technical scientific supper for different calculations and optimizingprocess.

  14. Efficiency assessment of bi-radiated screens and improved convective set of tubes during the modernization of PTVM-100 tower hot-water boiler based on controlled all-mode mathematic models of boilers on Boiler Designer software

    Science.gov (United States)

    Orumbayev, R. K.; Kibarin, A. A.; Khodanova, T. V.; Korobkov, M. S.

    2018-03-01

    This work contains analysis of technical values of tower hot-water boiler PTVM-100 when operating on gas and oil residual. After the test it became clear that due to the construction deficiency during the combustion of oil residual, it is not possible to provide long-term production of heat. There is also given a short review on modernization of PTVM-100 hot-water boilers. With the help of calculations based on controlled all-mode mathematic modules of hot-water boilers in BOILER DESIGNER software, it was shown that boiler modernization by use of bi-radiated screens and new convective set of tubes allows decreasing sufficiently the temperature of combustor output gases and increase reliability of boiler operation. Constructive changes of boiler unit suggested by authors of this work, along with increase of boiler’s operation reliability also allow to improve it’s heat production rates and efficiency rate up to 90,5% when operating on fuel oil and outdoor installation option.

  15. Development of Computational Capabilities to Predict the Corrosion Wastage of Boiler Tubes in Advanced Combustion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kung, Steven; Rapp, Robert

    2014-08-31

    coal-fired boilers resulting from the coexistence of sulfur and chlorine in the fuel. A new corrosion mechanism, i.e., “Active Sulfidation Corrosion Mechanism,” has been proposed to account for the accelerated corrosion wastage observed on the furnace walls of utility boilers burning coals containing sulfur and chlorine. In addition, a second corrosion mechanism, i.e., “Active Sulfide-to-Oxide Corrosion Mechanism,” has been identified to account for the rapid corrosion attack on superheaters and reheaters. Both of the newly discovered corrosion mechanisms involve the formation of iron chloride (FeCl2) vapor from iron sulfide (FeS) and HCl, followed by the decomposition of FeCl2 via self-sustaining cycling reactions. For higher alloys containing sufficient chromium, the attack on superheaters and reheaters is dominated by Hot Corrosion in the presence of a fused salt. Furthermore, two stages of the hot corrosion mechanism have been identified and characterized in detail. The initiation of hot corrosion attack induced by molten sulfate leads to Stage 1 “acidic” fluxing and re-precipitation of the protective scale formed initially on the deposit-covered alloy surfaces. Once the protective scale is penetrated, Stage 2 Hot Corrosion is initiated, which is dominated by “basic” fluxing and re-precipitation of the scale in the fused salt. Based on the extensive corrosion information generated from this project, corrosion modeling was performed using non-linear regression analysis. As a result of the modeling efforts, two predictive equations have been formulated, one for furnace walls and the other for superheaters and reheaters. These first-of-the-kind equations can be used to estimate the corrosion rates of boiler tubes based on coal chemistry, alloy compositions, and boiler operating conditions for advanced boiler systems.

  16. Oxidation study by Moessbauer and optic microscopy of steels from boiler tubes used in sugar industry

    International Nuclear Information System (INIS)

    Fajardo, M.; Perez Alcazar, G.A.; Aguilar, Y.

    1998-01-01

    Optic microscopy and Moessbauer spectroscopy were used to study the fail and the inner rusted surface of two boiler tubes used in the sugar industry, respectively. The studied tubes, of the type ASTM A 192, were found to have cracks. By optic microscopy it was observed that the failure begins in the inner surface with circumferential cracking. Also, inside and around the surface close to the cracks a rusted layer was detected. Powder from these layers was collected for Moessbauer spectroscopy analysis. By this method the presence of two or three types of Fe oxides such as wuestite, magnetite and hematite, was proved. These results permit to conclude that the failure mechanism was the thermal fatigue due to a hot work in an O 2 -rich vapor atmosphere. The rusted products are stable at high temperatures

  17. The creep life of superheater and reheater tubes under varying pressure conditions in operational boilers

    International Nuclear Information System (INIS)

    Mizen, D.C.; Plastow, B.

    1975-01-01

    The first of each manufacturer's 500 MW boilers supplied to the CEGB (Central Electricity Generating Board) have been subjected to an extensive programme of tests for performance optimization and safe operation. Around 250 thermocouples on superheater and reheater tubes have in each case been monitored as part of the exercise. The readings are corrected and used to compute creep rupture damage based on internationally agreed stress rupture data and a simple cumulative damage concept. Comparison of the design creep rupture life and the cumulative life consumed has in several applications been invaluable in influencing operating procedures and arranging tube modifications or replacements, so that loss of generation by creep rupture failure is minimized. (author)

  18. IGA/SCC propagation rate measurements on alloy 600 steam generator tubing using a side stream model boiler

    International Nuclear Information System (INIS)

    Takamatsu, H.; Matsueda, K.; Matsunaga, T.; Kitera, T.; Arioka, K.; Tsuruta, T.; Okamoto, S.

    1993-01-01

    IGA/SCC crack propagation rate measurements using various types of IGA/SCC predefected ALloy 600 tubing were tested in model boilers, a side stream model boiler at Ohi Unit 1 and similar model boilers in the laboratory. Types of IGA/SCC predefects introduced from the outside of the tubing were as follows. (1) Actual IGA/SCC predefect introduced by high temperature caustic environments; (2) Longitudinal predefect by electrodischarge machining (EDM) method, and then crack tip fatigue was introduced to serve as the marker on the fractured surface (EDM slit + fatigue). IGA/SCC crack propagation rate was measured after the destructive examination by Cr concentration profile on fracture surface for (1), and observation of intergranular fractured surface propagated from the marked fatigue was employed for (2) and (3) after the model boiler tests. As for the water chemistry conditions, mainly AVT (high N 2 H 4 ) + boric acid (5-10ppm as B in SGs) treatment for both model boilers, and some of the tests for the model boiler in the laboratory employed AVT (high N 2 H 4 ) without boric acid. The results of IGA/SCC crack propagation rate measurements were compared with each other, and the three methods employed showed a good coincidence with the rate of ca. 1 x 10 -5 mm/Hr for AVT (high N 2 H 4 ) + boric acid treatment condition, in the case that crack tip boron intensity (B/O value by IMMA analysis) of more than 1 was observed

  19. Corrosion/erosion detection of boiler tubes utilizing pulsed infrared imaging

    Science.gov (United States)

    Bales, Maurice J.; Bishop, Chip C.

    1995-05-01

    This paper discusses a new technique for locating and detecting wall thickness reduction in boiler tubes caused by erosion/corrosion. Traditional means for this type of defect detection utilizes ultrasonics (UT) to perform a point by point measurement at given intervals of the tube length, which requires extensive and costly shutdown or `outage' time to complete the inspection, and has led to thin areas going undetected simply because they were located in between the sampling points. Pulsed infrared imaging (PII) can provide nearly 100% inspection of the tubes in a fraction of the time needed for UT. The IR system and heat source used in this study do not require any special access or fixed scaffolding, and can be remotely operated from a distance of up to 100 feet. This technique has been tried experimentally in a laboratory environment and verified in an actual field application. Since PII is a non-contact technique, considerable time and cost savings should be realized as well as the ability to predict failures rather than repairing them once they have occurred.

  20. The effect of water jet lancing on furnace wall tubes of high slagged deposit fuel-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Vasiliev, V V; Kovalevitch, I A; Maidanik, M N [All-Union Heat Engineering Institute, Siberian Branch, Krasnoyarsk (USSR)

    1990-01-01

    In this paper the results of investigating the effectiveness of water jet lancing on furnace wall tubes of slagged deposits fuels fired boilers type E-500, P-64, P-67 are given. The boilers of these types are designed to burn Jugoslavian lignites are Beresovo lignites of the Kansk-Achinsk deposits. Recommendations for usage of low retractable, long retractable and long-range water blowers, depending on the design, produced in the USSR, the furnace dimension and stability of deposits are given as well.

  1. A thermodynamic approach on vapor-condensation of corrosive salts from flue gas on boiler tubes in waste incinerators

    International Nuclear Information System (INIS)

    Otsuka, Nobuo

    2008-01-01

    Thermodynamic equilibrium calculation was conducted to understand the effects of tube wall temperature, flue gas temperature, and waste chemistry on the type and amount of vapor-condensed 'corrosive' salts from flue gas on superheater and waterwall tubes in waste incinerators. The amount of vapor-condensed compounds from flue gases at 650-950 deg. C on tube walls at 350-850 deg. C was calculated, upon combustion of 100 g waste with 1.6 stoichiometry (in terms of the air-fuel ratio). Flue gas temperature, rather than tube wall temperature, influenced the deposit chemistry of boiler tubes significantly. Chlorine, sulfur, sodium, potassium, and calcium contents in waste affected it as well

  2. Developing an early laekage detection system for thermal power plant boiler tubes by using acoustic emission technology

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sang Bum [RECTUSON, Co., LTD, Masan (Korea, Republic of); Roh, Seon Man [Samcheonpo Division, Korea South-East Power Co., Samcheonpo (Korea, Republic of)

    2016-06-15

    A thermal power plant has a heat exchanger tube to collect and convert the heat generated from the high temperature and pressure steam to energy, but the tubes are arranged in a complex manner. In the event that a leakage occurs in any of these tubes, the high-pressure steam leaks out and may cause the neighboring tubes to rupture. This leakage can finally stop power generation, and hence there is a dire need to establish a suitable technology capable of detecting tube leaks at an early stage even before it occurs. As shown in this paper, by applying acoustic emission (AE) technology in existing boiler tube leak detection equipment (BTLD), we developed a system that detects these leakages early enough and generates an alarm at an early stage to necessitate action; the developed system works better that the existing system used to detect fine leakages. We verified the usability of the system in a 560 MW-class thermal power plant boiler by conducting leak tests by simulating leakages from a variety of hole sizes (⌀2, ⌀5, ⌀10 mm). Results show that while the existing fine leakage detection system does not detect fine leakages of ⌀2 mm and ⌀5 mm, the newly developed system could detect leakages early enough and generate an alarm at an early stage, and it is possible to increase the signal to more than 18 dB.

  3. Developing an early laekage detection system for thermal power plant boiler tubes by using acoustic emission technology

    International Nuclear Information System (INIS)

    Lee, Sang Bum; Roh, Seon Man

    2016-01-01

    A thermal power plant has a heat exchanger tube to collect and convert the heat generated from the high temperature and pressure steam to energy, but the tubes are arranged in a complex manner. In the event that a leakage occurs in any of these tubes, the high-pressure steam leaks out and may cause the neighboring tubes to rupture. This leakage can finally stop power generation, and hence there is a dire need to establish a suitable technology capable of detecting tube leaks at an early stage even before it occurs. As shown in this paper, by applying acoustic emission (AE) technology in existing boiler tube leak detection equipment (BTLD), we developed a system that detects these leakages early enough and generates an alarm at an early stage to necessitate action; the developed system works better that the existing system used to detect fine leakages. We verified the usability of the system in a 560 MW-class thermal power plant boiler by conducting leak tests by simulating leakages from a variety of hole sizes (⌀2, ⌀5, ⌀10 mm). Results show that while the existing fine leakage detection system does not detect fine leakages of ⌀2 mm and ⌀5 mm, the newly developed system could detect leakages early enough and generate an alarm at an early stage, and it is possible to increase the signal to more than 18 dB

  4. Analisa Efisiensi Water Tube Boiler Berbahan Bakar Fiber, Cangkang Sawit dan Kulit Kayu Menggunakan Metode Langsung

    OpenAIRE

    Gaol, Dosma Putra Lumban

    2016-01-01

    Some of the factors that affect the efficiency of the boiler is a superheater pressure, water feed temperature, steam temperature, the amount of steam produced, the amount of fuel consumption and calorific value fuel combustion. Steamtab chemicallogic use companion software to calculate the value of enthalpy. The aim of this study is to get relations variations in pressure superheater with boiler efficiency, the relationship of variation of temperature feed water to the boiler efficiency, the...

  5. Diagnosis of Heat Exchanger Tube Failure in Fossil Fuel Boilers Through Estimation of Steady State Operating Conditions

    International Nuclear Information System (INIS)

    Herszage, A.; Toren, M.

    1998-01-01

    Estimation of operating conditions for fossil fuel boiler heat exchangers is often required due to changes in working conditions, design modifications and especially for monitoring performance and failure diagnosis. Regular heat exchangers in fossil fuel boilers are composed of tube banks through which water or steam flow, while hot combustion (flue) gases flow outside the tubes. This work presents a top-down approach to operating conditions estimation based on field measurements. An example for a 350 MW unit superheater is thoroughly discussed. Integral calculations based on measurements for all unit heat exchangers (reheaters, superheaters) were performed first. Based on these calculations a scheme of integral conservation equations (lumped parameter) was then formulated at the single tube level. Steady state temperatures of superheater tube walls were obtained as a main output, and were compared to the maximum allowable operating temperatures of the tubes material. A combined lumped parameter - CFD (Computational Fluid Dynamics, FLUENT code) approach constitutes an efficient tool in certain cases. A brief report of such a case is given for another unit superheater. We conclude that steady state evaluations based on both integral and detailed simulations are a valuable monitoring and diagnosis tool for the power generation industry

  6. Thermal design of horizontal tube boilers. Numerical and experimental investigation; Modelisation thermique de bouilleurs a tubes horizontaux. Etude numerique et validation experimentale

    Energy Technology Data Exchange (ETDEWEB)

    Roser, R.

    1999-11-26

    This work concerns the thermal design of kettle reboilers. Current methods are highly inaccurate, regarded to the correlations for external heat transfer coefficient at one tube scale, as well as to two-phase flow modelling at boiler scale. The aim of this work is to improve these thermal design methods. It contains an experimental investigation with typical operating conditions of such equipment: an hydrocarbon (n-pentane) with low mass flux. This investigation has lead to characterize the local flow pattern through void fraction measurements and, from this, to develop correlations for void fraction, pressure drop and heat transfer coefficient. The approach is original, since the developed correlations are based on the liquid velocity at minimum cross section area between tubes, as variable characterizing the hydrodynamic effects on pressure drop and heat transfer coefficient. These correlations are shown to give much better results than those suggested up to now in the literature, which are empirical transpositions from methods developed for inside tube flows. Furthermore, the numerical code MC3D has been applied using the correlations developed in this work, leading to a modeling of the two-phase flow in the boiler, which is a significant progress compared to current simplified methods. (author)

  7. Effect of Prolong Aging to the Microstructure and Mechanical Properties of Boiler Tube

    International Nuclear Information System (INIS)

    Norasiah Abdul Kasim; Mohd Harun; Muhamad Rawi Mohd Zin; Zaifol Samsu; Mahdi Ezwan Mahmoud; Zaiton Selamat; Shariff Satar

    2013-01-01

    Boiler or steam generator is a device used to create steam by applying heat energy to water. For industrial applications, most boilers are used under extreme conditions, which require them to operating continuously or in a batch. Therefore constant heating and cooling will result into certain material failure, or when the operation itself exhibit a few malfunctions, it will affected the boiler condition and contribute to its failure. Hence the main emphasis on this study is investigating the effect of aging, with the influence of temperature by heating it into a period of time. Focus on understanding the changes occurred during the operating hour of boiler by simulating a short term aging experiment. The boilers structure material, Carbon Steel BS3509 used in this experiment were heated on a furnace with 500 and 550 centigrade for 19, 49, 72 and 191 hours. After the heating process, the metal specimens will be observed its micro structural changes and the oxide layer. The hardness will also be tested and taken accounted for before and after heating. The results and insight from the observation have been analyzed and discussed. (author)

  8. Simulation of Working Processes in the Water-Tube Boiler Furnace with the Purpose of Reducing Emissions of Nitrogen Oxides

    Directory of Open Access Journals (Sweden)

    Redko A.A.

    2017-04-01

    Full Text Available A significant number of domestic and industrial boilers are in operation in Ukraine. Nitrogen oxides are the most dangerous among all combustion products that pollute the atmosphere, therefore, one should take some measures for decreasing the formation of nitrogen oxides during combustion. The studies were carried out at the boilers of low power (100 kW with a tubular radiator and an open end. The studies in the furnaces of industrial steam boilers having a tubular radiator with a closed end have not been done. The numerical study results of the gaseous fuel combustion processes in the furnace of a DE-10/14 steam water-tube boiler are presented. The fuel-air mixture is formed by premixing the 15% part of the air with a primary burner twist factor n=2.4 and a secondary burner twist factor n=1.6, and an air excess factor αв=10. As a result of the studies, the temperature and velocity distributions of gases in the combustion chamber, the density of heat flows on the screen tubular surfaces, and the concentrations of the combustion components were determined. Flue gas recirculation in the volume of 80-100% is provided, and the reversible movement of combustion products towards the combustion front provides a reduction in the concentration of nitrogen oxides up to 123-125 mg/m3 at the furnace outlet. Disadvantages are the following: the formation of stagnant zones near the end of the secondary radiator. The optimum diameter of the tubular radiator equals to two burners diameters and tubular radiator is located at a distance of one meter from the burner cutoff.

  9. Oxidation study by Mössbauer and optic microscopy of steels from boiler tubes used in sugar industry

    Science.gov (United States)

    Fajardo, M.; Pérez Alcázar, G. A.; Aguilar, Y.

    1998-08-01

    Optic microscopy and Mössbauer spectroscopy were used to study the fail and the inner rusted surface of two boiler tubes used in the sugar industry, respectively. The studied tubes, of the type ASTM A 192, were found to have cracks. By optic microscopy it was observed that the failure begins in the inner surface with circumferential cracking. Also, inside and around the surface close to the cracks a rusted layer was detected. Powder from these layers was collected for Mössbauer spectroscopy analysis. By this method the presence of two or three types of Fe oxides such as wüstite, magnetite and hematite, was proved. These results permit to conclude that the failure mechanism was the thermal fatigue due to a hot work in an O2 -rich vapor atmosphere. The rusted products are stable at high temperatures.

  10. Effects of Different Fuel Specifications and Operation Conditions on the Performance of Coated and Uncoated Superheater Tubes in Two Different Biomass-Fired Boilers

    DEFF Research Database (Denmark)

    Wu, Duoli; Dahl, Kristian V.; Madsen, Jesper L.

    2018-01-01

    Fireside corrosionis a serious concern in biomass firing powerplants such that the efficiency of boilers is limited by high temperature corrosion. Application of protective coatings on superheater tubes is a possible solution to combat fireside corrosion. The current study investigates the corros......Fireside corrosionis a serious concern in biomass firing powerplants such that the efficiency of boilers is limited by high temperature corrosion. Application of protective coatings on superheater tubes is a possible solution to combat fireside corrosion. The current study investigates...... the corrosion performance of coated tubes compared to uncoated Esshete 1250 and TP347H tubes, which were exposed in two different biomass-fired boilers for one year. Data on the fuel used, temperature of the boilers, and temperature fluctuations are compared for the two boilers, and how these factors influence...... deposit formation, corrosion, and the stability of the coatings is discussed. The coatings (Ni and Ni2Al3) showed protective behavior ina wood-fired plant where the outlet steam temperature was 520 °C. However, at the plant that fired straw with an outlet steam temperature of 540 °C and where severe...

  11. Determining the parameters at which burnout occurs in the waterwall tubes of drum boilers

    Energy Technology Data Exchange (ETDEWEB)

    I.I. Belyakov [Central Boiler-Turbine Institute Research and Production Association (OAO TsKTI), St. Petersburg (Russian Federation)

    2007-09-15

    Parameters at which burnout occurs are presented that were obtained by measuring the temperature and heat fluxes during experiments carried out directly on a boiler. The results of a comparison between the obtained values and the data of investigations on a test facility are given.

  12. Corrosion behaviour of boiler tube materials during combustion of fuels containing Zn and Pb

    Energy Technology Data Exchange (ETDEWEB)

    Bankiewicz, D.

    2012-11-01

    Many power plants burning challenging fuels such as waste-derived fuels experience failures of the superheaters and/or increased waterwall corrosion due to aggressive fuel components already at low temperatures. To minimize corrosion problems in waste-fired boilers, the steam temperature is currently kept at a relatively low level which drastically limits power production efficiency. The elements found in deposits of waste and waste-derived fuels burning boilers that are most frequently associated with high-temperature corrosion are: Cl, S, and there are also indications of Br; alkali metals, mainly K and Na, and heavy metals such as Pb and Zn. The low steam pressure and temperature in waste-fired boilers also influence the temperature of the waterwall steel which is nowadays kept in the range of 300 deg C - 400 deg C. Alkali chloride (KCl, NaCl) induced high-temperature corrosion has not been reported to be particularly relevant at such low material temperatures, but the presence of Zn and Pb compounds in the deposits have been found to induce corrosion already in the 300 deg C - 400 deg C temperature range. Upon combustion, Zn and Pb may react with Cl and S to form chlorides and sulphates in the flue gases. These specific heavy metal compounds are of special concern due to the formation of low melting salt mixtures. These low melting, gaseous or solid compounds are entrained in the flue gases and may stick or condense on colder surfaces of furnace walls and superheaters when passing the convective parts of the boiler, thereby forming an aggressive deposit. A deposit rich in heavy metal (Zn, Pb) chlorides and sulphates increases the risk for corrosion which can be additionally enhanced by the presence of a molten phase. The objective of this study was to obtain better insight into high-temperature corrosion induced by Zn and Pb and to estimate the behaviour and resistance of some boiler superheater and waterwall materials in environments rich in those heavy metals

  13. A thin-lip rupture of carbon steel superheater boiler tube

    International Nuclear Information System (INIS)

    Khalil, E.O.; Alzoye, K.S.; Elwaer, A.M.

    1993-01-01

    A ruptured A 42 medium carbon steel tube was collected by the engineering department in one of our steam power stations. Inspection of ruptured tube revealed a thin - lip fracture with brownish thin layer of oxide film on inner tube surfaces. There was no evidence of pitting, the outer surfaces of the tube exhibited a general oxidized conditions. A micro section taken near the fracture surface consists of ferrite and martensite, the amount of martensite decreased as we away from the fracture surface. Presence of martensite phase in the microstructure indicates that the tube material has been overheated. An erosion corrosion mechanism in conjunction with overheated. An erosion corrosion mechanism in conjunction with overheating resulted in strength deterioration with consequent premature failure. 4 fig., 1 tab

  14. Pressure tests to assess the significance of defects in boiler and superheater tubing

    International Nuclear Information System (INIS)

    Guest, J.C.; Hutchings, J.A.

    1975-01-01

    Internal pressure tests on 9 per cent Cr-1 per cent Mo steel tubing containing artificial defects demonstrated that the resultant loss of strength was less than a simple calculation based on the reduced tube thickness would suggest. Bursting tests on tubes containing longitudinal defects of varying length, depth and acuity showed notch strengthening at ambient temperature and at 550 0 C. A flow stress concept developed for simple bursting tests was shown to apply to creep conditions at 550 0 C. Results of creep and short-term bursting tests show that the length as well as the depth of the defect is an important factor affecting the life of bursting strength of the tubes. Defects less than 10 per cent of the tube thickness were found to have an insignificant effect. (author)

  15. Long-term creep rupture strength of weldment of Fe-Ni based alloy as candidate tube and pipe for advanced USC boilers

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Gang; Sato, Takashi [Babcok-Hitachi K.K., Hiroshima (Japan). Kure Research Laboratory; Marumoto, Yoshihide [Babcok-Hitachi K.K., Hiroshima (Japan). Kure Div.

    2010-07-01

    A lot of works have been going to develop 700C USC power plant in Europe and Japan. High strength Ni based alloys such as Alloy 617, Alloy 740 and Alloy 263 were the candidates for boiler tube and pipe in Europe, and Fe-Ni based alloy HR6W (45Ni-24Fe-23Cr-7W-Ti) is also a candidate for tube and pipe in Japan. One of the Key issues to achieve 700 C boilers is the welding process of these alloys. Authors investigated the weldability and the long-term creep rupture strength of HR6W tube. The weldments were investigated metallurgically to find proper welding procedure and creep rupture tests are ongoing exceed 38,000 hours. The long-term creep rupture strengths of the HST weld joints are similar to those of parent metals and integrity of the weldments was confirmed based on with other mechanical testing results. (orig.)

  16. Design and implementation of a control system to improve the quality of the combustion gases in the fire-tube boiler of 5 BHP

    Directory of Open Access Journals (Sweden)

    Carlos Alfredo Pérez Albán

    2016-06-01

    Full Text Available The goal of this paper is the design and implementation of a system for controlling the quality of the combustion gases in a fire-tube boiler of 5 BHP. Based on the percentage of O2 present in the combustion gases, measured by a lambda sensor, the percentage of CO2 emitted into the atmosphere is determined. PID proportional control is responsible for the automatic regulation of the entry of air to the boiler by an actuator, according to the percentage of the oxygen concentration in the combustion gases. The control system has an HMI display and a modular PLC. The results achieved ensure pollutant gases emissions within the parameters established by current environmental standards, achieving the required quality of combustion gases and reducing the fuel consumption of the boiler.

  17. Failure analysis of a boiler tube in USC coal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Lee, N.H.; Kim, S.; Choe, B.H.; Yoon, K.B.; Kwon, D.I. [Kangnung National University, Kangnung (Republic of Korea)

    2009-10-15

    This paper presents failure analysis of final superheater tube in ultra-supercritical (USC) coal power plant. Visual inspection was performed to find out the characteristics of fracture of the as-received material. And the micro-structural changes such as grain growth and carbide coarsening was examined by scanning electron microscope. Detailed microscopic studies were made to find out the behavior of the scale exfoliation on the waterside of tubes. From those investigations, the creep rupture may be caused by the softened structure induced by carbide coarsening and accelerated by the metal temperature increase by the impediment of heat transfer due to voids.

  18. Combustion monitoring of a water tube boiler using a discriminant radial basis network.

    Science.gov (United States)

    Sujatha, K; Pappa, N

    2011-01-01

    This research work includes a combination of Fisher's linear discriminant (FLD) analysis and a radial basis network (RBN) for monitoring the combustion conditions for a coal fired boiler so as to allow control of the air/fuel ratio. For this, two-dimensional flame images are required, which were captured with a CCD camera; the features of the images-average intensity, area, brightness and orientation etc of the flame-are extracted after preprocessing the images. The FLD is applied to reduce the n-dimensional feature size to a two-dimensional feature size for faster learning of the RBN. Also, three classes of images corresponding to different burning conditions of the flames have been extracted from continuous video processing. In this, the corresponding temperatures, and the carbon monoxide (CO) emissions and those of other flue gases have been obtained through measurement. Further, the training and testing of Fisher's linear discriminant radial basis network (FLDRBN), with the data collected, have been carried out and the performance of the algorithms is presented. Copyright © 2010 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Relaxation and corrosion resistance of alloy 800 used for steam generator tubes of ship borne boilers

    International Nuclear Information System (INIS)

    Corrieu, J.M.; Cortial, F.; Maillard, J.L.; Vernot-Loier, C.; Lebeau, M.

    1994-01-01

    The INCO ''INCOLOY 800'' trademark groups the Fe-Cr-Ni alloys containing 30 to 35% nickel, 19 to 23% chromium, 0,15 to 0,60% aluminium, 0,15 to 0,60% titanium and less than 0,10% carbon contents, used as construction materials for condenser and heat exchanger tubes. In parallel with water chemistry control and studies aimed at reducing the residual stresses resulting from tube expansion, studies have been conducted to a better understanding of this alloy, its metallurgy and its corrosion behaviour under accurately defined fabrication and heat treatment conditions. The purpose of this paper is to present the results of a behaviour study of INDRET alloy 800 concerning isothermal relaxation and effects of the said relaxation heat treatments on alloy microstructure studied with a transmission electron-chemical method to determine the sensitiveness to intergranular corrosion, and by electrochemistry in pressurized hot water. (authors). 4 figs., 5 tabs., 7 refs

  20. A study on the concentration of CO by the length and the variation of the bent tube of the exhaust pipe for a household gas boiler

    International Nuclear Information System (INIS)

    Leem, Sa Hwan; Huh, Yong Jeong; Lee, Jong Rark

    2008-01-01

    Energy and environment become increasingly serious after the industrial revolution. The demand for gas as an ecofriendly energy source is also increasing. With the demand, the installation and the use of gas boilers have also increased, so the damage to human life by the waste gas (CO and CO 2 ) continues increasing every year. Hence, the aim of this study was to investigate the concentration of CO (Carbon Monoxide) by the length and the variation of the bent tube of the exhaust pipe by installing a boiler with the same method as a household boiler and to discover the harm to humans. For the effect of the length, the allowable concentration of CO is 50ppm, and the 3m of the once bent tube starts exceeding the allowable concentration of CO after 5 minutes, and the 4m and 5m starts exceeding after 3 minutes. In addition, the 1m of three times bent tube starts exceeding the allowable concentration of CO after 3 minutes

  1. Generalization of experimental data and development of recommendations for calculating heat transfer of a staggered tube bank with helical and ring extended-surface tubes in a perpendicular gas stream (for new formulation of standard method for boiler heat analyses)

    Energy Technology Data Exchange (ETDEWEB)

    Fomina, V N; Titova, E Ya; Migai, V K; Bystrov, P G; Pis' mennyi, E N [Vsesoyuznyi Teplotekhnicheskii Institut (USSR)

    1991-06-01

    Comparatively evaluates methods for determination of optimum design of extended-surface tubes used in water walls of boilers fired with coal and other fuels in commercial power plants in the USSR. The standard calculation methods introduced in 1973 and other methods developed and tested by individual research institutes of the USSR are described. New and original formulae based on the results of physical and mathematical modeling are evaluated. Heat transfer from flue gases to water walls is analyzed. Arrangement of tube banks, design of extended-surface tubes and other factors that influence heat transfer are considered. Evaluations show that from among the analyzed calculation methods the method developed by the KPI institute is superior to others (it is most accurate and universal). Investigations show that the coefficient of thermal efficiency of the economizers (1st and 2nd stage) of boilers fired with coal amounts to about 0.85. The coefficient considers effects of buildup on the economizer tubes. Use of the method is explained on example of boilers fired with black coal from the Ehkibastuz. 13 refs.

  2. Inelastic behaviour of solar boiler tubes subjected to cyclic thermal loading

    International Nuclear Information System (INIS)

    Gamby, D.; Pietri, P.; Bourdillon, H.

    1981-01-01

    Relying upon three-dimensional results previously obtained in the elastic range, we propose a simplified theory according to which each fiber of the tube portion undergoes either an uniaxial stress state (taking into account plastic flow with linear isotropic strain-hardening, possibly with creep) or a plane stress state in order to account for the ratchet phenomenon due to the inner fluid pressure. This approach allows to display and individualize the respective roles of strain-hardening, creep, fluid pressure and end-conditions; it also permits to calculate (most often in closed form) the deformations and stresses after a large number of cycles, which is not possible with more refined theories. Its accuracy has been assessed by computing the stresses and strains in the same situations for the first cycle by using an elasto-plastic shell theory (also taking into account creep influence), which revealed that in most cases our approach could give a good understanding of the phenomenon as well as a simple tool for actually calculating the mechanical quantities after a large number of cycles, in order to estimate the structure life-time. (orig./HP)

  3. Thermo-hydraulic characteristics of serpentine tubing in the boilers of gas cooled reactors under condition of rapid and slow depressurization

    International Nuclear Information System (INIS)

    Abouhadra, D.S.; Byrne, J.E.

    2003-01-01

    In nuclear reactors of the magnox or advanced gas cooled type, serpentine tubing is used in some designs to generate steam in a once through arrangement. The calculation of accidents using two phase flow codes requires knowledge of the heat transfer behaviour of the boiler steam side. A series of experiments to study the blowdown characteristics of a typical serpentine boiler section was devised in order to validate the MARTHA section of the MACE code used by nuclear electric . The tests were carried out on the thermal hydraulics experimental research assembly (THERA) loop at manchester university. Depressurization from an initial pressure of 60 bar, with fluid subcooling of 5 k, 50 k, and 100 k was controlled by discharging the test section contents through suitably chosen orifices to produce blowdown to 10% of the initial pressure over a time scale of 30 s to 3600 s. pressures and temperatures in the serpentine were measured at average time intervals of approximately 1 s

  4. Extensive feedwater quality control and monitoring concept for preventing chemistry-related failures of boiler tubes in a subcritical thermal power plant

    International Nuclear Information System (INIS)

    Vidojkovic, Sonja; Onjia, Antonije; Matovic, Branko; Grahovac, Nebojsa; Maksimovic, Vesna; Nastasovic, Aleksandra

    2013-01-01

    Prevention and minimizing corrosion processes on steam generating equipment is highly important in the thermal power industry. The maintenance of feedwater quality at a level corresponding to the standards of technological designing, followed by timely respond to the fluctuation of measured parameters, has a decisive role in corrosion prevention. In this study, the comprehensive chemical control of feedwater quality in 210 MW Thermal Power Plant (TPP) was carried out in order to evaluate its potentiality to assure reliable function of the boiler and discover possible irregularity that might be responsible for frequent boiler tube failures. Sensitive on-line and off-line analytical instruments were used for measuring key and diagnostic parameters considered to be crucial for boiler safety and performances. Obtained results provided evidences for exceeded levels of oxygen, silica, sodium, chloride, sulfate, copper, and conductivity what distinctly demonstrated necessity of feedwater control improvement. Consequently, more effective feedwater quality monitoring concept was recommended. In this paper, the explanation of presumable root causes of corrosive contaminants was given including basic directions for their maintenance in proscribed limits. -- Highlights: • Feedwater quality monitoring practice in a thermal power plant has been evaluated. • The more efficient feedwater quality control have been applied. • Analysis of feedwater quality parameters has been performed. • Exceeded levels of corrosive contaminants were found. • Recommendations for their maintenance at proscribed values were given

  5. Failure Analysis of 600 MW Supercritical Boiler Water Wall

    OpenAIRE

    Fu Huilin; Cai Zhengchun; Yan Xiaozhong; He Jinqiao; Zhou Yucai

    2013-01-01

    Boiler tube often causes abnormal boiler outage, bringing greater economic losses. This thesis mainly comes from the dynamics of boiler water, boiler furnace accident location of wall temperature distribution to explore the cause of the accident boiler. Calculation results show that the deformation will seriously reduce the boiler allowable maximum temperature difference between the screens. And the boiler is not over-temperature, low temperature difference between the screens, which have bur...

  6. Improvement of fire-tube boilers calculation methods by the numerical modeling of combustion processes and heat transfer in the combustion chamber

    Science.gov (United States)

    Komarov, I. I.; Rostova, D. M.; Vegera, A. N.

    2017-11-01

    This paper presents the results of study on determination of degree and nature of influence of operating conditions of burner units and flare geometric parameters on the heat transfer in a combustion chamber of the fire-tube boilers. Change in values of the outlet gas temperature, the radiant and convective specific heat flow rate with appropriate modification of an expansion angle and a flare length was determined using Ansys CFX software package. Difference between values of total heat flow and bulk temperature of gases at the flue tube outlet calculated using the known methods for thermal calculation and defined during the mathematical simulation was determined. Shortcomings of used calculation methods based on the results of a study conducted were identified and areas for their improvement were outlined.

  7. Structured Mathematical Modeling of Industrial Boiler

    OpenAIRE

    Aziz, Abdullah Nur; Nazaruddin, Yul Yunazwin; Siregar, Parsaulian; Bindar, Yazid

    2014-01-01

    As a major utility system in industry, boilers consume a large portion of the total energy and costs. Significant reduction of boiler cost operation can be gained through improvements in efficiency. In accomplishing such a goal, an adequate dynamic model that comprehensively reflects boiler characteristics is required. This paper outlines the idea of developing a mathematical model of a water-tube industrial boiler based on first principles guided by the bond graph method in its derivation. T...

  8. Cracking and corrosion recovery boiler

    Energy Technology Data Exchange (ETDEWEB)

    Suik, H. [Tallinn Technical University, Horizon Pulp and Paper, Tallinn (Estonia)

    1998-12-31

    The corrosion of heat surfaces and the cracking the drums are the main problems of the recovery boiler. These phenomena have been appeared during long-term operation of boiler `Mitsubishi - 315` erected at 1964. Depth of the crack is depending on the number of shutdowns and on operation time. Corrosion intensity of different heat surfaces is varying depend on the metal temperature and the conditions at place of positioning of tube. The lowest intensity of corrosion is on the bank tubes and the greatest is on the tubes of the second stage superheater and on the tubes at the openings of air ports. (orig.) 5 refs.

  9. Cracking and corrosion recovery boiler

    Energy Technology Data Exchange (ETDEWEB)

    Suik, H [Tallinn Technical University, Horizon Pulp and Paper, Tallinn (Estonia)

    1999-12-31

    The corrosion of heat surfaces and the cracking the drums are the main problems of the recovery boiler. These phenomena have been appeared during long-term operation of boiler `Mitsubishi - 315` erected at 1964. Depth of the crack is depending on the number of shutdowns and on operation time. Corrosion intensity of different heat surfaces is varying depend on the metal temperature and the conditions at place of positioning of tube. The lowest intensity of corrosion is on the bank tubes and the greatest is on the tubes of the second stage superheater and on the tubes at the openings of air ports. (orig.) 5 refs.

  10. EFFICIENCY IMPROVEMENT IN INDUSTRIAL BOILER BY FLUE GAS DUCT INSULATION

    OpenAIRE

    Sanjay H. Zala

    2017-01-01

    Now a days in industry major losses are find out so here we calculate these losses and find out efficiency of boiler. Boiler efficiency and energy losses from boiler are important parameter for any industry using boiler. In this work a detailed analysis was carried out for boiler at Anish Chemicals Bhavnagar. It is a combined water and fire tube boiler using biomass coal as fuel. Boiler efficiency calculated by direct method is in range of (78.5% to 81.6%). Major losses from boiler are heat ...

  11. Long term properties and microstructural evolution of 18Cr-10Ni-3Cu-Ti-Nb austenitic stainless steel for boiler tube application

    Energy Technology Data Exchange (ETDEWEB)

    Minami, Y.; Fukui, T.; Ono, T. [TenarisNKK Tubes, Kawasaki, Kanagawa (Japan); Caminada, S. [TenarisDalmine, Dalmine, BG (Italy)

    2010-07-01

    The allowable tensile stress of 0.1C-18Cr-10Ni-3Cu-Ti-Nb steel (TEMPALOY AA-1; ASME C.C. 2512) is more than 30% higher compared with that of ASME SA-213 Grade TP347H in the temperature range 600-700 C. This high creep rupture strength is obtained by the precipitation of MC and M{sub 23}C{sub 6} carbides, and Cu-rich phase. Long term creep rupture tests over 10{sup 5}h enabled to verify the superior creep rupture strength of this steel. The investigation of microstructural evolution on the creep ruptured and aged specimens has shown the high structural stability of this material. Hardness and impact properties after high temperature aging reveal similar performance as conventional 18-8 stainless steels. Excellent steam oxidation resistance can be achieved by a shot-blasting method. The scale thickness of shot-blasted tube after 1000h at 750 C is below a few micron meters. These results have revealed that the mechanical properties and environmental resistance of this steel enable the use of TEMPALOY AA-1 in the latest generation of advanced USC boiler. (orig.)

  12. Structured Mathematical Modeling of Industrial Boiler

    Directory of Open Access Journals (Sweden)

    Abdullah Nur Aziz

    2014-04-01

    Full Text Available As a major utility system in industry, boilers consume a large portion of the total energy and costs. Significant reduction of boiler cost operation can be gained through improvements in efficiency. In accomplishing such a goal, an adequate dynamic model that comprehensively reflects boiler characteristics is required. This paper outlines the idea of developing a mathematical model of a water-tube industrial boiler based on first principles guided by the bond graph method in its derivation. The model describes the temperature dynamics of the boiler subsystems such as economizer, steam drum, desuperheater, and superheater. The mathematical model was examined using industrial boiler performance test data.It can be used to build a boiler simulator or help operators run a boiler effectively.

  13. HR boiler

    Energy Technology Data Exchange (ETDEWEB)

    1982-08-01

    A number of manufacturers of central heating boilers in the Netherlands have produced high-efficiency boilers, all carrying the GIVEG-HR seal of approval (GIVEG is the manufacturers' association in the Netherlands, and HR stands for 'hoog rendement': high efficiency). Efficiences were considerably improved by reducing flue, idling and radiation losses. Control and safety, discharges of flue gases and condensate need special attention. Whether installation of a GIVEG-HR boiler is profitable in view of the cost/profit ratio, will have to be determined from case to case. N.V. Nederlandse Gasunie felt it was time to present the facts so far in a way specially aimed at the construction industry. This special edition of 'Gas and Architecture' answers a number of questions which the architect or consultant engineer might have in particular before advising on the installation of the new boiler in houses and other buildings in the interests of energy saving. A technical description of the HR boiler covers the backgrounds of its development and considers the role of the Netherlands government as regards to the introduction of the boiler.

  14. Efficient boiler operations sourcebook

    Energy Technology Data Exchange (ETDEWEB)

    Payne, F.W. (comp.)

    1985-01-01

    This book emphasizes the practical aspects of industrial and commercial boiler operations. It starts with a comprehensive review of general combustion and boiler fundamentals and then deals with specific efficiency improvement methods, and the cost savings which result. The book has the following chapter headings: boiler combustion fundamentals; boiler efficiency goals; major factors controlling boiler efficiency; boiler efficiency calculations; heat loss; graphical solutions; preparation for boiler testing; boiler test procedures; efficiency-related boiler maintenance procedures; boiler tune-up; boiler operational modifications; effect of water side and gas side scale deposits; load management; auxillary equipment to increase boiler efficiency; air preheaters and economizers; other types of auxillary equipment; combustion control systems and instrumentation; boiler O/sub 2/ trim controls; should you purchase a new boiler.; financial evaluation procedures; case studies. The last chapter includes a case study of a boiler burning pulverized coal and a case study of stoker-fired coal.

  15. Chemical cleaning of UK AGR boilers

    International Nuclear Information System (INIS)

    Rudge, A.; Turner, P.; Ghosh, A.; Clary, W.; Tice, D.

    2002-01-01

    For the first time in their operational lives, UK advanced gas-cooled reactor once-through boilers have been chemically cleaned. Chemical cleaning was necessary to avoid lost output resulting from boiler pressure drops, which had been increasing for a number of years. Chemical cleaning of these boilers presents a number of unique difficulties. These include lack of access to the boilers, highly sensitised 316H superheater sections that cannot be excluded from the cleaning flow path, relatively thin boiler tube walls and an intolerance to boiler tube failure because of the role of the boilers in nuclear decay heat removal. The difficulties were overcome by implementing the clean in a staged manner, starting with an extensive materials testwork programme to select and then to substantiate the cleaning process. The selected process was based on ammoniated citric acid plus formic acid for the principal acid cleaning stage. Materials testwork was followed by an in-plant trial clean of six boiler tubes, further materials testwork and the clean of a boiler tube in a full-scale test rig. An overview is presented of the work that was carried out to demonstrate that the clean could be carried out safely, effectively and without leading to unacceptable corrosion losses. Full-scale chemical cleaning was implemented by using as much of the existing plant as possible. Careful control and monitoring was employed to ensure that the cleaning was implemented according to the specified design, thus ensuring that a safe and effective clean was carried out. Full-scale cleaning has resulted in significant boiler pressure drop recovery, even though the iron burden was relatively low and cleaning was completed in a short time. (orig.)

  16. Life cycle assessment for spray coatings applied to the heating tubes of PFBC boiler; Kaatsu ryudoso boiler sonai kan e tekiyosareru yosha coating no life cycle assessment (LCA hyoka)

    Energy Technology Data Exchange (ETDEWEB)

    Sonoya, K; Kihara, S [Ishikawajima-Harima Heavy Industries, Co. Ltd., Tokyo (Japan)

    1996-12-25

    LCA (Life cycle assessment) is a systematic process used to calculate and evaluate the environmental impacts of products. Because boiler components are now exposed a more severe erosion/corrosion environment by, improving efficiency of thermal power plant, it is expected that the use of thermal spray coatings will increase. The LCA method was attempted to apply to various thermal spray coatings for PFBC (Pressurized Fluidized Bed Combustion) and evaluate the eco-friendly, coatings. The result was gained that all the alumina coatings have good characteristics. In fact the Al2O3-40%ZrO2 coating by APS has the lowest environmental impact and the best erosion resistance, it may be considered the most effective coating. 4 refs., 12 figs., 1 tab.

  17. Life extension of boilers using weld overlay protection

    Energy Technology Data Exchange (ETDEWEB)

    Lai, G.; Hulsizer, P. [Welding Services Inc., Norcross, GA (United States); Brooks, R. [Welding Services Inc., Welding Services Europe, Spijkenisse (Netherlands)

    1998-12-31

    The presentation describes the status of modern weld overlay technology for refurbishment, upgrading and life extension of boilers. The approaches to life extension of boilers include field overlay application, shop-fabricated panels for replacement of the worn, corroded waterwall and shop-fabricated overlay tubing for replacement of individual tubes in superheaters, generating banks and other areas. The characteristics of weld overlay products are briefly described. Also discussed are successful applications of various corrosion-resistant overlays for life extension of boiler tubes in waste-to-energy boilers, coal-fired boilers and chemical recovery boilers. Types of corrosion and selection of weld overlay alloys in these systems are also discussed. (orig.) 14 refs.

  18. Life extension of boilers using weld overlay protection

    Energy Technology Data Exchange (ETDEWEB)

    Lai, G; Hulsizer, P [Welding Services Inc., Norcross, GA (United States); Brooks, R [Welding Services Inc., Welding Services Europe, Spijkenisse (Netherlands)

    1999-12-31

    The presentation describes the status of modern weld overlay technology for refurbishment, upgrading and life extension of boilers. The approaches to life extension of boilers include field overlay application, shop-fabricated panels for replacement of the worn, corroded waterwall and shop-fabricated overlay tubing for replacement of individual tubes in superheaters, generating banks and other areas. The characteristics of weld overlay products are briefly described. Also discussed are successful applications of various corrosion-resistant overlays for life extension of boiler tubes in waste-to-energy boilers, coal-fired boilers and chemical recovery boilers. Types of corrosion and selection of weld overlay alloys in these systems are also discussed. (orig.) 14 refs.

  19. Smooth Surfaces: A review of current and planned smooth surface technologies for fouling resistance in boiler

    Energy Technology Data Exchange (ETDEWEB)

    Corkery, Robert; Baefver, Linda; Davidsson, Kent; Feiler, Adam

    2012-02-15

    Here we have described the basics of boilers, fuels, combustion, flue gas composition and mechanisms of deposition. We have reviewed coating technologies for boiler tubes, including their materials compositions, nano structures and performances. The surface forces in boilers, in particular those relevant to formation of unwanted deposits in boilers have also been reviewed, and some comparative calculations have been included to indicate the procedures needed for further study. Finally practical recommendations on the important considerations in minimizing deposition on boiler surfaces are made

  20. Steam generators and waste heat boilers for process and plant engineers

    CERN Document Server

    Ganapathy, V

    2014-01-01

    Incorporates Worked-Out Real-World ProblemsSteam Generators and Waste Heat Boilers: For Process and Plant Engineers focuses on the thermal design and performance aspects of steam generators, HRSGs and fire tube, water tube waste heat boilers including air heaters, and condensing economizers. Over 120 real-life problems are fully worked out which will help plant engineers in evaluating new boilers or making modifications to existing boiler components without assistance from boiler suppliers. The book examines recent trends and developments in boiler design and technology and presents novel idea

  1. A novel design for a cheap high temperature solar collector: The rotating solar boiler

    NARCIS (Netherlands)

    Luijtelaer, van J.P.H.; Kroon, M.C.

    2009-01-01

    In this work a novel type of high temperature solar collector is designed: the rotating solar boiler. This rotating solar boiler consists of two concentric tubes. The inner tube, called absorber, absorbs sunlight and boils water. The outer transparent tube, called cover, is filled with air. The

  2. Ultrasonic boiler inspection and economic analysis guidelines

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Boiler tube failures cause approximately 6% availability loss of large fossil-fired power generating plants. This loss can be reduced by systematic approaches using ultrasonic examination and root cause failure analysis methods. Two projects sponsored by EPRI have provided utility engineers with guidelines for performing ultrasonic examinations and with details on 22 types of tube failure mechanisms. A manual has been published that provides descriptions of typical locations, superficial appearances, damage mechanisms, metallurgy, microstructural changes, likely root causes, and potential corrective actions. Application of the principles in the manual is being demonstrated in an EPRI-funded project at 10 electric utilities over the next two years. Guidelines have been published that prescribe the activities necessary for ultrasonic examinations of boiler tubes. Eight essential elements of a boiler examination should be performed to assure that possible economic benefits are obtained. Work was supported by EPRI under RP 1890 and RP 1865. A software package has been developed for effectively planning inspections for wall thinning in fossil-fired boiler tubing. The software assists in minimizing costs associated with maintenance, such as inspection and repair, while the life of the boiler is maximized

  3. On-line monitoring system for utility boiler diagnostics

    International Nuclear Information System (INIS)

    Radovanovic, P.M.; Afgan, N.H.; Caralho, M.G.

    1997-01-01

    The paper deals with the new developed modular type Monitoring System for Utility Boiler Diagnostics. Each module is intended to assess the specific process and can be used as a stand alone application. Four modules are developed, namely: LTC - module for the on-line monitoring of parameters related to the life-time consumption of selected boiler components; TRD - module for the tube rupture detection by the position and working fluid Ieakage quantity; FAM - module for the boiler surfaces fouling (slagging) assessment and FLAP - module for visualization of the boiler furnace flame position. All four modules are tested on respective pilot plants built oil the 200 and 300 MWe utility boilers. Monitoring System is commercially available and can be realized in any combination of its modules depending on demands induced by the operational problems of specific boiler. Further development of Monitoring System is performed in accordance with the respective EU project on development of Boiler Expert System. (Author)

  4. A rule-based industrial boiler selection system

    NARCIS (Netherlands)

    Tan, C.F.; Khalil, S.N.; Karjanto, J.; Tee, B.T.; Wahidin, L.S.; Chen, W.; Rauterberg, G.W.M.; Sivarao, S.; Lim, T.L.

    2015-01-01

    Boiler is a device used for generating the steam for power generation, process use or heating, and hot water for heating purposes. Steam boiler consists of the containing vessel and convection heating surfaces only, whereas a steam generator covers the whole unit, encompassing water wall tubes,

  5. Increasing the thermal efficiency of boiler plant

    Directory of Open Access Journals (Sweden)

    Uyanchinov Evgeniy

    2017-01-01

    Full Text Available The thermal efficiency increase of boiler plant is actual task of scientific and technical researches. The optimization of boiler operating conditions is task complex, which determine by most probable average load of boiler, operating time and characteristics of the auxiliary equipment. The work purpose – the determination of thermodynamic efficiency increase ways for boiler plant with a gas-tube boiler. The tasks, solved at the research are the calculation of heat and fuel demand, the exergetic analysis of boilerhouse and heat network equipment, the determination of hydraulic losses and exergy losses due to restriction. The calculation was shown that the exergy destruction can be reduced by 2.39% due to excess air reducing to 10%; in addition the oxygen enrichment of air can be used that leads to reducing of the exergy destruction rate. The processes of carbon deposition from the side of flame and processes of scale formation on the water side leads to about 4.58% losses of fuel energy at gas-tube boiler. It was shown that the exergy losses may be reduced by 2.31% due to stack gases temperature reducing to 148 °C.

  6. Water side corrosion prevention in boilers

    International Nuclear Information System (INIS)

    Zeid, A.

    1993-01-01

    Corrosion may be defined as a naturally occurring physical and chemical deterioration of a material due to reaction with the environment or surrounding atmosphere. In boilers the material is subjected on both sides to two different media which may cause severe corrosion. At the water side the content of O 2 considered one of the principal factors which determine the extent of corrosion in the boiler tubes. This paper deals with certain conditions that result in the increase of O 2 in the boiler water and hence increase the corrosion rate, to minimize the effect of these conditions a chemical treatment was carried out the results obtained indicated the success of the treatment procedure in corrosion prevention and boiler material protection. The treatment is traditional. But the study indicates how a simple mean could be applied to solve a serious problem. 4 tab

  7. Boilers, evaporators, and condensers

    International Nuclear Information System (INIS)

    Kakac, S.

    1991-01-01

    This book reports on the boilers, evaporators and condensers that are used in power plants including nuclear power plants. Topics included are forced convection for single-phase side heat exchangers, heat exchanger fouling, industrial heat exchanger design, fossil-fuel-fired boilers, once through boilers, thermodynamic designs of fossil fuel-first boilers, evaporators and condensers in refrigeration and air conditioning systems (with respect to reducing CFC's) and nuclear steam generators

  8. Control Properties of Bottom Fired Marine Boilers

    DEFF Research Database (Denmark)

    Solberg, Brian; Andersen, Palle; Karstensen, Claus M. S.

    2007-01-01

    This paper focuses on model analysis of a dynamic model of a bottom fired one-pass smoke tube boiler. Linearized versions of the model are analyzed and show large variations in system gains at steady state as function of load whereas gain variations near the desired bandwidth are small. An analys...

  9. Design of Boiler Welding for Improvement of Lifetime and Cost Control

    OpenAIRE

    Thong-On, Atcharawadi; Boonruang, Chatdanai

    2016-01-01

    Fe-2.25Cr-1Mo a widely used material for headers and steam tubes of boilers. Welding of steam tube to header is required for production of boiler. Heat affected zone of the weld can have poor mechanical properties and poor corrosion behavior leading to weld failure. The cost of material used for steam tube and header of boiler should be controlled. This study propose a new materials design for boiler welding to improve the lifetime and cost control, using tungsten inert gas (TIG) welding of F...

  10. Factors affecting stress assisted corrosion cracking of carbon steel under industrial boiler conditions

    Science.gov (United States)

    Yang, Dong

    Failure of carbon steel boiler tubes from waterside has been reported in the utility boilers and industrial boilers for a long time. In industrial boilers, most waterside tube cracks are found near heavy attachment welds on the outer surface and are typically blunt, with multiple bulbous features indicating a discontinuous growth. These types of tube failures are typically referred to as stress assisted corrosion (SAC). For recovery boilers in the pulp and paper industry, these failures are particularly important as any water leak inside the furnace can potentially lead to smelt-water explosion. Metal properties, environmental variables, and stress conditions are the major factors influencing SAC crack initation and propagation in carbon steel boiler tubes. Slow strain rate tests (SSRT) were conducted under boiler water conditions to study the effect of temperature, oxygen level, and stress conditions on crack initation and propagation on SA-210 carbon steel samples machined out of boiler tubes. Heat treatments were also performed to develop various grain size and carbon content on carbon steel samples, and SSRTs were conducted on these samples to examine the effect of microstructure features on SAC cracking. Mechanisms of SAC crack initation and propagation were proposed and validated based on interrupted slow strain tests (ISSRT). Water chemistry guidelines are provided to prevent SAC and fracture mechanics model is developed to predict SAC failure on industrial boiler tubes.

  11. Model boiler studies on deposition and corrosion

    International Nuclear Information System (INIS)

    Balakrishnan, P.V.; McVey, E.G.

    1977-09-01

    Deposit formation was studied in a model boiler, with sea-water injections to simulate the in-leakage which could occur from sea-water cooled condensers. When All Volatile Treatment (AVT) was used for chemistry control the deposits consisted of the sea-water salts and corrosion products. With sodium phosphate added to the boiler water, the deposits also contained the phosphates derived from the sea-water salts. The deposits were formed in layers of differing compositions. There was no significant corrosion of the Fe-Ni-Cr alloy boiler tube under deposits, either on the open area of the tube or in crevices. However, carbon steel that formed a crevice around the tube was corroded severely when the boiler water did not contain phosphate. The observed corrosion of carbon steel was caused by the presence of acidic, highly concentrated chloride solution produced from the sea-water within the crevice. Results of theoretical calculations of the composition of the concentrated solution are presented. (author)

  12. Control Properties of Bottom Fired Marine Boilers

    DEFF Research Database (Denmark)

    Solberg, Brian; Andersen, Palle; Karstensen, Claus M. S.

    2005-01-01

    This paper focuses on model analysis of a dynamic model of a bottom fired one-pass smoke tube boiler. Linearised versions of the model are analysed to determine how gain, time constants and right half plane zeros (caused by the shrink-and-swell phenomenon) depend on the steam flow load. Furthermore...... the interactions in the system are inspected to analyse potential benefit from using a multivariable control strategy in favour of the current strategy based on single loop theory. An analysis of the nonlinear model is carried out to further determine the nonlinear characteristics of the boiler system...

  13. Thermo hydraulics of a steam boiler forced circulation

    International Nuclear Information System (INIS)

    Tucakovic, Dragan; Zivanovic, Titoslav; Stevanovic, Vladimir

    2006-01-01

    In order to minimize the dryout at the steam boiler furnace in the Thermal Power Plant Kolubara B, designed are inner rifled wall tubes. This type of tubes, with many spiral grooves cut into the bore, prevents film boiling and enables the nucleate boiling be still maintained under the condition of vapour quality being app. 1. To verify the choice of the rifled tubes instead of the cheaper, smooth tubes type being justified, analyzed is the change of the actual and critical vapour quality with the furnace height, under uniform and non-uniform heat flu through evaporator walls. Furthermore, made are hydraulic calculations for various steam boiler loads, in case of both rifled and smooth tubes types, with the purpose to check the rifles influence to pressure drop increase in comparison with the smooth tubes. Also, checked is the selection of the circulation pump. Key words: evaporator, forced circulation, rifled tubes, critical vapour quality, pressure drop

  14. Boiler water regime

    Science.gov (United States)

    Khavanov, Pavel; Chulenyov, Anatoly

    2017-10-01

    Active development of autonomous heating the past 25 years has led to the widespread use of hot-water boilers of small capacity up to 2.5 MW. Rational use of the design of autonomous sources of heating boilers design features significantly improve their technical, economic and operational performance. This publication reviewed and analyzed a number of features of the design, operation and exploitation of boilers of small capacity, significantly affecting the efficiency and reliability of their application.

  15. Chemical cleaning of AGR boilers

    International Nuclear Information System (INIS)

    Moore, S.V.; Moore, W.; Rantell, A.

    1978-01-01

    AGR boilers are likely to require post service chemical cleaning to remove accumulated oxides at intervals of 15 - 35 kh. The need to clean will be based on an assessment of such factors as the development of flow imbalances through parallel tubes induced by the formation of rough oxide surfaces, an increasing risk of localised corrosion as the growth of porous oxides proceeds and the risk of tube blockage caused by the exfoliation of steam-grown oxides. The study has shown what heterogeneous multilayer oxides possessing a range of physical and chemical properties form on the alloy steels. They include porous and compact magnetites, chromium spinels and sesquioxide. Ammoniated citric acid has been shown to remove deposited and water-grown magnetites from the carbon and alloy steels but will not necessarily remove the substituted spinels grown on the alloy steels or the potentially spalling steam-grown magnetite on the A1SI 316 superheater. Citric acid supplemented with the reducing agent glyoxal completely removes all oxides from the boiler except the protective inner spinel formed on the 316. Removal of the spinels and compact magnetites occurs more by undercutting and physical detachment than by the dissolution. (author)

  16. Boiler conversions for biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kinni, J [Tampella Power Inc., Tampere (Finland)

    1997-12-31

    Boiler conversions from grate- and oil-fired boilers to bubbling fluidized bed combustion have been most common in pulp and paper industry. Water treatment sludge combustion, need for additional capacity and tightened emission limits have been the driving forces for the conversion. To accomplish a boiler conversion for biofuel, the lower part of the boiler is replaced with a fluidized bed bottom and new fuel, ash and air systems are added. The Imatran Voima Rauhalahti pulverized-peat-fired boiler was converted to bubbling fluidized bed firing in 1993. In the conversion the boiler capacity was increased by 10 % to 295 MWth and NO{sub x} emissions dropped. In the Kymmene Kuusankoski boiler, the reason for conversion was the combustion of high chlorine content biosludge. The emissions have been under general European limits. During the next years, the emission limits will tighten and the boilers will be designed for most complete combustion and compounds, which can be removed from flue gases, will be taken care of after the boiler. (orig.) 3 refs.

  17. Boiler conversions for biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kinni, J. [Tampella Power Inc., Tampere (Finland)

    1996-12-31

    Boiler conversions from grate- and oil-fired boilers to bubbling fluidized bed combustion have been most common in pulp and paper industry. Water treatment sludge combustion, need for additional capacity and tightened emission limits have been the driving forces for the conversion. To accomplish a boiler conversion for biofuel, the lower part of the boiler is replaced with a fluidized bed bottom and new fuel, ash and air systems are added. The Imatran Voima Rauhalahti pulverized-peat-fired boiler was converted to bubbling fluidized bed firing in 1993. In the conversion the boiler capacity was increased by 10 % to 295 MWth and NO{sub x} emissions dropped. In the Kymmene Kuusankoski boiler, the reason for conversion was the combustion of high chlorine content biosludge. The emissions have been under general European limits. During the next years, the emission limits will tighten and the boilers will be designed for most complete combustion and compounds, which can be removed from flue gases, will be taken care of after the boiler. (orig.) 3 refs.

  18. Condensing boiler applications in the process industry

    International Nuclear Information System (INIS)

    Chen, Qun; Finney, Karen; Li, Hanning; Zhang, Xiaohui; Zhou, Jue; Sharifi, Vida; Swithenbank, Jim

    2012-01-01

    Major challenging issues such as climate change, energy prices and fuel security have focussed the attention of process industries on their energy efficiency and opportunities for improvement. The main objective of this research study was to investigate technologies needed to exploit the large amount of low grade heat available from a flue gas condensing system through industrial condensing boilers. The technology and application of industrial condensing boilers in various heating systems were extensively reviewed. As the condensers require site-specific engineering design, a case study was carried out to investigate the feasibility (technically and economically) of applying condensing boilers in a large scale district heating system (40 MW). The study showed that by recovering the latent heat of water vapour in the flue gas through condensing boilers, the whole heating system could achieve significantly higher efficiency levels than conventional boilers. In addition to waste heat recovery, condensing boilers can also be optimised for emission abatement, especially for particle removal. Two technical barriers for the condensing boiler application are corrosion and return water temperatures. Highly corrosion-resistant material is required for condensing boiler manufacture. The thermal design of a 'case study' single pass shell-and-tube condensing heat exchanger/condenser showed that a considerable amount of thermal resistance was on the shell-side. Based on the case study calculations, approximately 4900 m 2 of total heat transfer area was required, if stainless steel was used as a construction material. If the heat transfer area was made of carbon steel, then polypropylene could be used as the corrosion-resistant coating material outside the tubes. The addition of polypropylene coating increased the tube wall thermal resistance, hence the required heat transfer area was approximately 5800 m 2 . Net Present Value (NPV) calculations showed that the choice of a carbon

  19. CANDU steam generator tubing material service experience and allied development

    International Nuclear Information System (INIS)

    Hart, A.E.; Lesurf, J.E.

    1976-01-01

    This paper covers the following aspects for the tube materials in CANDU-PHW steam generators: inservice performance with respect to tube leaks and coolant activity attributable to boiler tube corrosion, selection of tube materials for use with non-boiling and boiling primary coolants, supporting development on corrosion, vibration, fretting wear, tube inspection, leak detection and plugging of defective tubes. (author)

  20. Effect of Water Quality on the Performance of Boiler in Nigerian Petroleum Industry

    Directory of Open Access Journals (Sweden)

    J. O. ODIGURE

    2005-06-01

    Full Text Available This work investigates quality of water used in boilers of Refinery Company in Nigeria. The results shows that the quality of water fed to boilers are off specification. Low water quality used in boilers led to frequent failure of the boilers as a result of tube rupture. This has resulted into low capacity utilization and loss of processing fees. The poor performance of the boiler feed treatment plant is attributable to the deplorable condition of water intake plant, raw water treatment, demineralization plant, change in raw water quality and non-functioning of the polisher unit.

  1. Optimisation of Marine Boilers using Model-based Multivariable Control

    DEFF Research Database (Denmark)

    Solberg, Brian

    Traditionally, marine boilers have been controlled using classical single loop controllers. To optimise marine boiler performance, reduce new installation time and minimise the physical dimensions of these large steel constructions, a more comprehensive and coherent control strategy is needed....... This research deals with the application of advanced control to a specific class of marine boilers combining well-known design methods for multivariable systems. This thesis presents contributions for modelling and control of the one-pass smoke tube marine boilers as well as for hybrid systems control. Much...... of the focus has been directed towards water level control which is complicated by the nature of the disturbances acting on the system as well as by low frequency sensor noise. This focus was motivated by an estimated large potential to minimise the boiler geometry by reducing water level fluctuations...

  2. High gradient magnetic filters for boiler water treatment

    International Nuclear Information System (INIS)

    Harland, J.R.; Nichols, R.M.

    1977-01-01

    Heavy metal oxide suspended solids in those steam condensates recycled to the boilers produce buildup within the boiler tubes which can lead to unequal and reduced heat transfer efficiency, and indirectly, to boiler tube failures. Recommended reductions in such suspended solids in feedwater to the economizers of modern high pressure boilers to levels of under 10 ppb have been published. The industrially-available SALA-HGMF magnetic filter has achieved these desired suspended solids levels in treating steam condensates. The high gradient magnetic filter has been shown in pilot tests to achieve and even exceed the recommended low level suspended solids in a practical and efficient industrial system. Such electromagnetic filters, when combined with good system chemistry, have achieved low single number parts per billion levels of several heavy metals with very high single-pass efficiencies

  3. Fire-side corrosion in power-station boilers

    Energy Technology Data Exchange (ETDEWEB)

    Cutler, A J.B.; Flatley, T; Hay, K A

    1978-10-01

    The steel tubing of a modern power-station boiler operates at up to 650/sup 0/C (a dull red heat) in the very corrosive environment produced by the combustion gases and ash particles. Within the tubes, whose walls are around 5mm thick, 2000 tons of steam are generated per hour at temperatures up to 565/sup 0/C and pressures up to 170 bar. Several forms of metal corrosion may occur on the fireside surface of these tubes and on other boiler components. The designed 20-year operating life of the stainless-steel superheater and reheater tubes can be much reduced at temperatures above 600/sup 0/C by attack from molten salts formed beneath the deposited ash on the upstream tube surfaces. Mild steel evaporator tubes lining the furnace wall may suffer similarly if flame impingement allows the local release of volatile chlorine compounds from coal particles on the tube surface. Uncooled metal components supporting and aligning the boiler tubes may reach 1000/sup 0/C and are particularly susceptible to corrosion. CEGB research effort has been applied to quantify the rate of corrosion and to obtain an understanding of the complex corrosion mechanisms, so that ways of minimizing or preventing their occurrence may be found. These include the optimization of the combustion chemistry, design modifications such as shielding certain vulnerable tubes, and the selection of improved alloys and the use of ''co-extruded'' tubing.

  4. Tube to tube excursive instability - sensitivities and transients

    International Nuclear Information System (INIS)

    Brown, M.; Layland, M.W.

    1980-01-01

    A simple basic analysis of excursive instability in a boiler tube shows how it depends upon operating conditions and physical properties. A detailed mathematical model of an AGR boiler is used to conduct a steady state parameter sensitivity survey. It is possible from this basis to anticipate the effects of changes in operating conditions and changes in design parameters upon tube to tube stability. Dynamic responses of tubes operating near the stability threshold are examined using a mathematical model. Simulated excursions are triggered by imparting small abrupt pressure changes on the boiler inlet pressure. The influences of the magnitude of the pressure change, waterside friction factor and gas side coupling between tubes are examined. (author)

  5. Electric utility CFB boilers

    International Nuclear Information System (INIS)

    Fairbanks, D.A.

    1991-01-01

    This paper reports on Circulating Fluidized Bed (CFB) boiler technology which caught the attention of boiler users: first for its technical advantages of reduced air emissions and low grade fuel tolerance, then later for its problems in becoming a reliable process. Refractory longevity and fuel feed reliability plagued a number of new installations. The efficacy of CFB technology is now more assured with the recent success of Texas-New Mexico Power Company's 160 MWe CFB based units, the world's largest operating CFB boilers. Most of the more notable CFB development problems have been successfully addressed by these units. The TNP units have demonstrated that CFB's can reliable produce high capacity factors at low emission rates using a fuel that has traditionally hampered the operation of pulverized coal (PC) boilers and without the attendant problems associated with sulfur scrubbers required by PC boilers

  6. Solved and unsolved problems in boiler systems. Learning from accidents

    International Nuclear Information System (INIS)

    Ozawa, Mamoru

    2000-01-01

    This paper begins with a brief review on the similarity law of conventional fossil-fuel-fired boilers. The concept is based on the fact that the heat release due to combustion in the furnace is restricted by the furnace volume but the heat absorption is restricted by the heat transfer surface area. This means that a small-capacity boiler has relatively high specific furnace heat release rate, about 10 MW/m 3 , and on the contrary a large-capacity boiler has lower value. The surface-heat-flux limit is mainly dominated by the CHF inside the water-wall tubes of the boiler furnace, about 350 kW/m 2 . This heat-flux limit is almost the same order independently on the capacity of boilers. For the safety of water-walls, it is essential to retain suitable water circulation, i.e. circulation ratio and velocity of water. This principle is a common knowledge of boiler designer, but actual situation is not the case. Newly designed boilers often suffer from similar accidents, especially burnout due to circulation problems. This paper demonstrates recent accidents encountered in practical boilers, and raises problems of rather classical but important two-phase flow and heat transfer. (author)

  7. DYMEL code for prediction of dynamic stability limits in boilers

    International Nuclear Information System (INIS)

    Deam, R.T.

    1980-01-01

    Theoretical and experimental studies of Hydrodynamic Instability in boilers were undertaken to resolve the uncertainties of the existing predictive methods at the time the first Advanced Gas Cooled Reactor (AGR) plant was commissioned. The experiments were conducted on a full scale electrical simulation of an AGR boiler and revealed inadequacies in existing methods. As a result a new computer code called DYMEL was developed based on linearisation and Fourier/Laplace Transformation of the one-dimensional boiler equations in both time and space. Beside giving good agreement with local experimental data, the DYMEL code has since shown agreement with stability data from the plant, sodium heated helical tubes, a gas heated helical tube and an electrically heated U-tube. The code is now used widely within the U.K. (author)

  8. CECIL lances Bruce's boilers

    International Nuclear Information System (INIS)

    Malaugh, J.; Monaghan, D.

    1994-01-01

    Over the past few years Ontario Hydro has become increasingly concerned about accumulations of sludge in its nuclear plant boilers, so a comprehensive sludge management programme has been instituted to combat build-up. This included developing the tele-operated robot CECIL (Consolidated Edison Combined Inspection and Lancing) equipment, originally designed for work in PWRs, for CANDU boilers. This required a significantly reconfigured robotic system as well as modifications to the boilers themselves. Work on the Bruce A reactor is described. (4 figures). (author)

  9. Modelling transition states of a small once-through boiler

    Energy Technology Data Exchange (ETDEWEB)

    Talonpoika, T [Lappeenranta Univ. of Technology (Finland). Dept. of Energy Technology

    1998-12-31

    This article presents a model for the unsteady dynamic behaviour of a once-through counter flow boiler that uses an organic working fluid. The boiler is a compact waste-heat boiler without a furnace and it has a preheater, a vaporiser and a superheater. The relative lengths of the boiler parts vary with the operating conditions since they are all parts of a single tube. The boiler model is presented using a selected example case that uses toluene as the process fluid and flue gas from natural gas combustion as the heat source. The dynamic behaviour of the boiler means transition from the steady initial state towards another steady state that corresponds to the changed process conditions. The solution method chosen is to find such a pressure of the process fluid that the mass of the process fluid in the boiler equals the mass calculated using the mass flows into and out of the boiler during a time step, using the finite difference method. A special method of fast calculation of the thermal properties is used, because most of the calculation time is spent in calculating the fluid properties. The boiler is divided into elements. The values of the thermodynamic properties and mass flows are calculated in the nodes that connect the elements. Dynamic behaviour is limited to the process fluid and tube wall, and the heat source is regarded as to be steady. The elements that connect the preheater to the vaporiser and the vaporiser to the superheater are treated in a special way that takes into account a flexible change from one part to the other. The initial state of the boiler is received from a steady process model that is not a part of the boiler model. The known boundary values that may vary during the dynamic calculation were the inlet temperature and mass flow rates of both the heat source fluid and the process fluid. The dynamic boiler model is analysed for linear and step charges of the entering fluid temperatures and flow rates. The heat source side tests show that

  10. Modelling transition states of a small once-through boiler

    Energy Technology Data Exchange (ETDEWEB)

    Talonpoika, T. [Lappeenranta Univ. of Technology (Finland). Dept. of Energy Technology

    1997-12-31

    This article presents a model for the unsteady dynamic behaviour of a once-through counter flow boiler that uses an organic working fluid. The boiler is a compact waste-heat boiler without a furnace and it has a preheater, a vaporiser and a superheater. The relative lengths of the boiler parts vary with the operating conditions since they are all parts of a single tube. The boiler model is presented using a selected example case that uses toluene as the process fluid and flue gas from natural gas combustion as the heat source. The dynamic behaviour of the boiler means transition from the steady initial state towards another steady state that corresponds to the changed process conditions. The solution method chosen is to find such a pressure of the process fluid that the mass of the process fluid in the boiler equals the mass calculated using the mass flows into and out of the boiler during a time step, using the finite difference method. A special method of fast calculation of the thermal properties is used, because most of the calculation time is spent in calculating the fluid properties. The boiler is divided into elements. The values of the thermodynamic properties and mass flows are calculated in the nodes that connect the elements. Dynamic behaviour is limited to the process fluid and tube wall, and the heat source is regarded as to be steady. The elements that connect the preheater to the vaporiser and the vaporiser to the superheater are treated in a special way that takes into account a flexible change from one part to the other. The initial state of the boiler is received from a steady process model that is not a part of the boiler model. The known boundary values that may vary during the dynamic calculation were the inlet temperature and mass flow rates of both the heat source fluid and the process fluid. The dynamic boiler model is analysed for linear and step charges of the entering fluid temperatures and flow rates. The heat source side tests show that

  11. Increase of efficiency and reliability of liquid fuel combustion in small-sized boilers

    Science.gov (United States)

    Roslyakov, P. V.; Proskurin, Yu V.; Ionkin, I. L.

    2017-11-01

    One of the ways to increase the efficiency of using fuels is to create highly efficient domestic energy equipment, in particular small-sized hot-water boilers in autonomous heating systems. Increasing the efficiency of the boiler requires a reduction in the temperature of the flue gases leaving, which, in turn, can be achieved by installing additional heating surfaces. The purpose of this work was to determine the principal design solutions and to develop a draft design for a high-efficiency 3-MW hot-water boiler using crude oil as its main fuel. Ensuring a high efficiency of the boiler is realized through the use of an external remote economizer, which makes it possible to reduce the dimensions of the boiler, facilitate the layout of equipment in a limited size block-modular boiler house and virtually eliminate low-temperature corrosion of boiler heat exchange surfaces. In the article the variants of execution of the water boiler and remote economizer are considered and the preliminary design calculations of the remote economizer for various schemes of the boiler layout in the Boiler Designer software package are made. Based on the results of the studies, a scheme was chosen with a three-way boiler and a two-way remote economizer. The design of a three-way fire tube hot water boiler and an external economizer with an internal arrangement of the collectors, providing for its location above the boiler in a block-modular boiler house and providing access for servicing both a remote economizer and a hot water boiler, is proposed. Its mass-dimensional and design parameters are determined. In the software package Boiler Designer thermal, hydraulic and aerodynamic calculations of the developed fire tube boiler have been performed. Optimization of the boiler design was performed, providing the required 94% efficiency value for crude oil combustion. The description of the developed flue and fire-tube hot water boiler and the value of the main design and technical and

  12. ENERGY STAR Certified Boilers

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 3.0 ENERGY STAR Program Requirements for Boilers that are effective as of October 1,...

  13. Charting the boiler market

    International Nuclear Information System (INIS)

    2003-01-01

    The ''boiler market'' of electricity, sometimes called unsecured transmission, is electric power consumption that in public statistics is restricted by the obligation of the customers to cut their consumption at short notice and therefore are granted some discount on the network lease. The present document is part of a project that aims to provide a better understanding of the flexibility in the Norwegian power market, limited by the power-intensive industry and the boiler market. It discusses the boiler market. It begins with a discusses of the available statistics, where different sources show very dissimilar consumption figures. Then it examines how the consumption in the boiler market developed during the winter 2002/2003. Finally, there is a description of the regulations of unsecured transmission and how the various network owners adapt to the regulations.

  14. Dynamic Boiler Performance

    DEFF Research Database (Denmark)

    Sørensen, Kim

    Traditionally, boilers have been designed mainly focussing on the static operation of the plant. The dynamic capability has been given lower priority and the analysis has typically been limited to assuring that the plant was not over-stressed due to large temperature gradients. New possibilities...... developed. Analyzing boilers for dynamic operation gives rise to a number of opposing aims: shrinking and swelling, steam quality, stress levels, control system/philosophy, pressurization etc. Common for these opposing aims is that an optimum can be found for selected operation conditions. The framework has...... for buying and selling energy has increased the focus on the dynamic operation capability, efciency, emissions etc. For optimizing the design of boilers for dynamic operation a quantication of the dynamic capability is needed. A framework for optimizing design of boilers for dynamic operation has been...

  15. Materials and boiler rig testing to support chemical cleaning of once-through AGR boilers

    International Nuclear Information System (INIS)

    Tice, D.R.; Platts, N.; Raffel, A.S.; Rudge, A.

    2002-01-01

    An extensive programme of work has been carried out to evaluate two candidate inhibited cleaning solutions for possible implementation on plant, which would be the first chemical clean of an AGR boiler. The two candidate cleaning solutions considered were a Stannine-inhibited citric acid/formic acid mixture (GOM106) and inhibited hydrofluoric acid. Citric acid-based cleaning processes are widely used within the UK Power Industry. The GOM106 solution, comprising a mixture of 3% citric acid, 0.5% formic acid and 0.05% Stannine LTP inhibitor, buffered with ammonia to pH 3.5, was developed specifically for the AGR boilers during the 1970's. Although a considerable amount of materials testing work was carried out by British Energy's predecessor companies to produce a recommended cleaning procedure there were some remaining concerns with the use of GOM106, from these earlier studies, for example, an increased risk of pitting attack associated with the removal of thick 9Cr oxide deposits and a risk of unacceptable damage in critical locations such as the upper transition joints and other weld locations. Hence, additional testing was still required to validate the solution for use on plant. Inhibited hydrofluoric acid (HFA) was also evaluated as an alternative reagent to GOM106. HFA has been used extensively for cleaning mild and low'alloy steel boiler tubes in fossil-fired plant in the UK and elsewhere in Europe and is known to remove oxide quickly. Waste treatment is also easier than for the GOM106 process and some protection against damage to the boiler tube materials is provided by complexing of fluoride with ferric ion. Validation of the potential reagents and inhibitors was achieved by assessing the rate and effectiveness of oxide removal from specimens of helical boiler tubing and welds, together with establishing the extent of any metal loss or localised damage. The initial materials testing resulted in the inhibited ammoniated citric / formic acid reagent being

  16. Millwright Apprenticeship. Related Training Modules. 7.1-7.9 Boilers.

    Science.gov (United States)

    Lane Community Coll., Eugene, OR.

    This packet, part of the instructional materials for the Oregon apprenticeship program for millwright training, contains nine modules covering boilers. The modules provide information on the following topics: fire and water tube types of boilers, construction, fittings, operation, cleaning, heat recovery systems, instruments and controls, and…

  17. The impact of feedwater and condensate return excursions on boiler system component failures

    Energy Technology Data Exchange (ETDEWEB)

    Esmacher, Mel J. [GE Water and Process Technologies, The Woodlands, TX (United States); Rossi, Anthony [GE Water and Process Technologies, Trevose, PA (United States)

    2010-02-15

    During boiler operation, the transport of contaminants in boiler feedwater or condensate return via hardness excursions or transport of metal oxides due to corrosion can cause fouling and subsequent tube failure due to under-deposit corrosion or overheating. Case histories are reviewed and suitable corrective actions discussed. (orig.)

  18. MODELLING, SIMULATING AND OPTIMIZING BOILERS

    DEFF Research Database (Denmark)

    Sørensen, Kim; Condra, Thomas Joseph; Houbak, Niels

    2004-01-01

    In the present work a framework for optimizing the design of boilers for dynamic operation has been developed. A cost function to be minimized during the optimization has been formulated and for the present design variables related to the Boiler Volume and the Boiler load Gradient (i.e. ring rate...... on the boiler) have been dened. Furthermore a number of constraints related to: minimum and maximum boiler load gradient, minimum boiler size, Shrinking and Swelling and Steam Space Load have been dened. For dening the constraints related to the required boiler volume a dynamic model for simulating the boiler...... performance has been developed. Outputs from the simulations are shrinking and swelling of water level in the drum during for example a start-up of the boiler, these gures combined with the requirements with respect to allowable water level uctuations in the drum denes the requirements with respect to drum...

  19. Oxy-Combustion Boiler Material Development

    Energy Technology Data Exchange (ETDEWEB)

    Gagliano, Michael; Seltzer, Andrew; Agarwal, Hans; Robertson, Archie; Wang, Lun

    2012-01-31

    Under U.S. Department of Energy Cooperative Agreement No. DE-NT0005262 Foster Wheeler North America Corp conducted a laboratory test program to determine the effect of oxy-combustion on boiler tube corrosion. In this program, CFD modeling was used to predict the gas compositions that will exist throughout and along the walls of air-fired and oxy-fired boilers operating with low to high sulfur coals. Test coupons of boiler tube materials were coated with deposits representative of those coals and exposed to the CFD predicted flue gases for up to 1000 hours. The tests were conducted in electric tube furnaces using oxy-combustion and air-fired flue gases synthesized from pressurized cylinders. Following exposure, the test coupons were evaluated to determine the total metal wastage experienced under air and oxy-combustions conditions and materials recommendations were made. Similar to air-fired operation, oxy-combustion corrosion rates were found to vary with the boiler material, test temperature, deposit composition, and gas composition. Despite this, comparison of air-fired and oxy-fired corrosion rates showed that oxy-firing rates were, for the most part, similar to, if not lower than those of air-firing; this finding applied to the seven furnace waterwall materials (wrought and weld overlay) and the ten superheater/reheater materials (wrought and weld overlay) that were tested. The results of the laboratory oxy-combustion tests, which are based on a maximum bulk flue gas SO2 level of 3200 ppmv (wet) / 4050 ppmv (dry), suggest that, from a corrosion standpoint, the materials used in conventional subcritical and supercritical, air-fired boilers should also be suitable for oxy-combustion retrofits. Although the laboratory test results are encouraging, they are only the first step of a material evaluation process and it is recommended that follow-on corrosion tests be conducted in coal-fired boilers operating under oxy-combustion to provide longer term (one to two year

  20. Oxy-Combustion Boiler Material Development

    Energy Technology Data Exchange (ETDEWEB)

    Michael Gagliano; Andrew Seltzer; Hans Agarwal; Archie Robertson; Lun Wang

    2012-01-31

    Under U.S. Department of Energy Cooperative Agreement No. DE-NT0005262 Foster Wheeler North America Corp conducted a laboratory test program to determine the effect of oxy-combustion on boiler tube corrosion. In this program, CFD modeling was used to predict the gas compositions that will exist throughout and along the walls of air-fired and oxy-fired boilers operating with low to high sulfur coals. Test coupons of boiler tube materials were coated with deposits representative of those coals and exposed to the CFD predicted flue gases for up to 1000 hours. The tests were conducted in electric tube furnaces using oxy-combustion and air-fired flue gases synthesized from pressurized cylinders. Following exposure, the test coupons were evaluated to determine the total metal wastage experienced under air and oxy-combustions conditions and materials recommendations were made. Similar to air-fired operation, oxy-combustion corrosion rates were found to vary with the boiler material, test temperature, deposit composition, and gas composition. Despite this, comparison of air-fired and oxy-fired corrosion rates showed that oxy-firing rates were, for the most part, similar to, if not lower than those of air-firing; this finding applied to the seven furnace waterwall materials (wrought and weld overlay) and the ten superheater/reheater materials (wrought and weld overlay) that were tested. The results of the laboratory oxy-combustion tests, which are based on a maximum bulk flue gas SO{sub 2} level of 3200 ppmv (wet) / 4050 ppmv (dry), suggest that, from a corrosion standpoint, the materials used in conventional subcritical and supercritical, air-fired boilers should also be suitable for oxy-combustion retrofits. Although the laboratory test results are encouraging, they are only the first step of a material evaluation process and it is recommended that follow-on corrosion tests be conducted in coal-fired boilers operating under oxy-combustion to provide longer term (one to

  1. Mitigating the Risk of Stress Corrosion of Austenitic Stainless Steels in Advanced Gas Cooled Reactor Boilers

    International Nuclear Information System (INIS)

    Bull, A.; Owen, J.; Quirk, G.; G, Lewis; Rudge, A.; Woolsey, I.S.

    2012-09-01

    Advanced Gas-Cooled Reactors (AGRs) operated in the UK by EDF Energy have once-through boilers, which deliver superheated steam at high temperature (∼500 deg. C) and pressure (∼150 bar) to the HP turbine. The boilers have either a serpentine or helical geometry for the tubing of the main heat transfer sections of the boiler and each individual tube is fabricated from mild steel, 9%Cr1%Mo and Type 316 austenitic stainless steel tubing. Type 316 austenitic stainless steel is used for the secondary (final) superheater and steam tailpipe sections of the boiler, which, during normal operation, should operate under dry, superheated steam conditions. This is achieved by maintaining a specified margin of superheat at the upper transition joint (UTJ) between the 9%Cr1%Mo primary superheater and the Type 316 secondary superheater sections of the boiler. Operating in this mode should eliminate the possibility of stress corrosion cracking of the Type 316 tube material on-load. In recent years, however, AGRs have suffered a variety of operational problems with their boilers that have made it difficult to maintain the specified superheat margin at the UTJ. In the case of helical boilers, the combined effects of carbon deposition on the gas side and oxide deposition on the waterside of the tubing have resulted in an increasing number of austenitic tubes operating with less than the specified superheat margin at the UTJ and hence the possibility of wetting the austenitic section of the boiler. Some units with serpentine boilers have suffered creep-fatigue damage of the high temperature sections of the boiler, which currently necessitates capping the steam outlet temperature to prevent further damage. The reduction in steam outlet temperature has meant that there is an increased risk of operation with less than the specified superheat margin at the UTJ and hence stress corrosion cracking of the austenitic sections of the boiler. In order to establish the risk of stress

  2. Studies Concerning Water-Surface Deposits in Recovery Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Strandberg, O; Arvesen, J; Dahl, L

    1971-11-15

    The Feed-water Committee of the Stiftelsen Svensk Cellulosaforskning (Foundation for Swedish Cellulose Research) has initiated research and investigations which aim to increase knowledge about water-surface deposits in boiler tubes, and the resulting risks of gas-surface corrosion in chemical recovery boilers (sulphate pulp industry). The Committee has arranged with AB Atomenergi, Studsvik, for investigations into the water-surface deposits on tubes from six Scandinavian boilers. These investigations have included direct measurements of the thermal conductivity of the deposits, and determinations of their quantity, thickness and structure have been carried out. Previous investigations have shown that gas-surface corrosion can occur at tube temperatures above 330 deg C. The measured values for the thermal conductivity of the deposits indicate that even with small quantities of deposit (c. 1 g/dm2 ) and a moderate boiler pressure (40 atm), certain types of deposit can give rise to the above-mentioned surface temperature, at which the risk of gas-surface corrosion becomes appreciable. For higher boiler pressures the risk is great even with a minimal layer of deposit. The critical deposit thickness can be as low as 0.1 mm

  3. Materials for the pulp and paper industry. Section 1: Development of materials for black liquor recovery boilers

    Energy Technology Data Exchange (ETDEWEB)

    Keiser, J.R.; Hubbard, C.R.; Payzant, E.A. [Oak Ridge National Lab., TN (United States)] [and others

    1997-04-01

    Black liquor recovery boilers are essential components of kraft pulp and paper mills because they are a critical element of the system used to recover the pulping chemicals required in the kraft pulping process. In addition, the steam produced in these boilers is used to generate a significant portion of the electrical power used in the mill. Recovery boilers require the largest capital investment of any individual component of a paper mill, and these boilers are a major source of material problems in a mill. The walls and floors of these boilers are constructed of tube panels that circulate high pressure water. Molten salts (smelt) accumulate on the floor of recovery boilers, and leakage of water into the boiler can result in a violent explosion when the leaked water instantly vaporizes upon contacting the molten smelt. Because corrosion of the conventionally-used carbon steel tubing was found to be excessive in the lower section of recovery boilers, use of stainless steel/carbon steel co-extruded tubing was adopted for boiler walls to lessen corrosion and reduce the likelihood of smelt/water explosions. Eventually, this co-extruded or composite (as it is known in the industry) tubing was selected for use as a portion or all of the floor of recovery boilers, particularly those operating at pressures > 6.2 MPa (900 psi), because of the corrosion problems encountered in carbon steel floor tubes. Since neither the cause of the cracking nor an effective solution has been identified, this program was established to develop a thorough understanding of the degradation that occurs in the composite tubing used for walls and floors. This is being accomplished through a program that includes collection and review of technical reports, examination of unexposed and cracked tubes from boiler floors, computer modeling to predict residual stresses under operating conditions, and operation of laboratory tests to study corrosion, stress corrosion cracking, and thermal fatigue.

  4. Super Boiler: First Generation, Ultra-High Efficiency Firetube Boiler

    Energy Technology Data Exchange (ETDEWEB)

    None

    2006-06-01

    This factsheet describes a research project whose goal is to develop and demonstrate a first-generation ultra-high-efficiency, ultra-low emissions, compact gas-fired package boiler (Super Boiler), and formulate a long-range RD&D plan for advanced boiler technology out to the year 2020.

  5. Application of the decree 2910 for coal fired boilers; Application de l`arrete 2910 aux chaudieres a charbon

    Energy Technology Data Exchange (ETDEWEB)

    Hing, K. [CDF Energie, Charbonnages de France, 92 - Rueil-Malmaison (France)

    1997-12-31

    The impacts of the new French decree 2910 concerning the classification of all combustion equipment with regards to their energy sources, energy efficiency and pollution control, on 2 to 20 MW coal-fired boilers, are discussed, with emphasis on their pollutant emissions (SO{sub 2}, NO{sub x} and ashes). The compositions of several coals is presented and the various types of coal-fired boilers adapted to the new decree are presented: automatic boilers, dense fluidized bed boilers, vibrating and chain grids with fume tubes and water tubes

  6. Control Properties of Bottom Fired Marine Boilers

    DEFF Research Database (Denmark)

    Solberg, Brian; Andersen, Palle; Karstensen, Claus M. S.

    2005-01-01

    This paper focuses on model analysis of a dynamic model of a bottom fired one-pass smoke tube boiler. Linearised versions of the model are analysed to determine how gain, time constants and right half plane zeros (caused by the shrink-and-swell phenomenon) depend on the steam flow load. Furthermore...... the interactions in the system are inspected to analyse potential benefit from using a multivariable control strategy in favour of the current strategy based on single loop theory. An analysis of the nonlinear model is carried out to further determine the nonlinear characteristics of the boiler system...... and to verify whether nonlinear control is needed. Finally a controller based on single loop theory is used to analyse if input constraints become active when rejecting transient behaviour from the disturbance steam flow. The model analysis shows large variations in system gains at steady state as function...

  7. Ash particle erosion on steam boiler convective section

    Energy Technology Data Exchange (ETDEWEB)

    Meuronen, V

    1998-12-31

    In this study, equations for the calculation of erosion wear caused by ash particles on convective heat exchanger tubes of steam boilers are presented. A new, three-dimensional test arrangement was used in the testing of the erosion wear of convective heat exchanger tubes of steam boilers. When using the sleeve-method, three different tube materials and three tube constructions could be tested. New results were obtained from the analyses. The main mechanisms of erosion wear phenomena and erosion wear as a function of collision conditions and material properties have been studied. Properties of fossil fuels have also been presented. When burning solid fuels, such as pulverized coal and peat in steam boilers, most of the ash is entrained by the flue gas in the furnace. In bubbling and circulating fluidized bed boilers, particle concentration in the flue gas is high because of bed material entrained in the flue gas. Hard particles, such as sharp edged quartz crystals, cause erosion wear when colliding on convective heat exchanger tubes and on the rear wall of the steam boiler. The most important ways to reduce erosion wear in steam boilers is to keep the velocity of the flue gas moderate and prevent channelling of the ash flow in a certain part of the cross section of the flue gas channel, especially near the back wall. One can do this by constructing the boiler with the following components. Screen plates can be used to make the velocity and ash flow distributions more even at the cross-section of the channel. Shield plates and plate type constructions in superheaters can also be used. Erosion testing was conducted with three types of tube constructions: a one tube row, an in- line tube bank with six tube rows, and a staggered tube bark with six tube rows. Three flow velocities and two particle concentrations were used in the tests, which were carried out at room temperature. Three particle materials were used: quartz, coal ash and peat ash particles. Mass loss

  8. Thermal-hydraulic analysis of a 600 MW supercritical CFB boiler with low mass flux

    International Nuclear Information System (INIS)

    Pan Jie; Yang Dong; Chen Gongming; Zhou Xu; Bi Qincheng

    2012-01-01

    Supercritical Circulating Fluidized Bed (CFB) boiler becomes an important development trend for coal-fired power plant and thermal-hydraulic analysis is a key factor for the design and operation of water wall. According to the boiler structure and furnace-sided heat flux, the water wall system of a 600 MW supercritical CFB boiler is treated in this paper as a flow network consisting of series-parallel loops, pressure grids and connecting tubes. A mathematical model for predicting the thermal-hydraulic characteristics in boiler heating surface is based on the mass, momentum and energy conservation equations of these components, which introduces numerous empirical correlations available for heat transfer and hydraulic resistance calculation. Mass flux distribution and pressure drop data in the water wall at 30%, 75% and 100% of the boiler maximum continuous rating (BMCR) are obtained by iteratively solving the model. Simultaneity, outlet vapor temperatures and metal temperatures in water wall tubes are estimated. The results show good heat transfer performance and low flow resistance, which implies that the water wall design of supercritical CFB boiler is applicable. - Highlights: → We proposed a model for thermal-hydraulic analysis of boiler heating surface. → The model is applied in a 600 MW supercritical CFB boiler. → We explore the pressure drop, mass flux and temperature distribution in water wall. → The operating safety of boiler is estimated. → The results show good heat transfer performance and low flow resistance.

  9. Integrated boiler, superheater, and decomposer for sulfuric acid decomposition

    Science.gov (United States)

    Moore, Robert [Edgewood, NM; Pickard, Paul S [Albuquerque, NM; Parma, Jr., Edward J.; Vernon, Milton E [Albuquerque, NM; Gelbard, Fred [Albuquerque, NM; Lenard, Roger X [Edgewood, NM

    2010-01-12

    A method and apparatus, constructed of ceramics and other corrosion resistant materials, for decomposing sulfuric acid into sulfur dioxide, oxygen and water using an integrated boiler, superheater, and decomposer unit comprising a bayonet-type, dual-tube, counter-flow heat exchanger with a catalytic insert and a central baffle to increase recuperation efficiency.

  10. Wylfa nuclear boiler repair. How a major problem was solved

    International Nuclear Information System (INIS)

    1977-09-01

    The CEGB has published a booklet, with coloured illustrations, that describes in detail the story of an unusually difficult boiler repair on a Magnox reactor at Wylfa nuclear power station. Boiler leaks affected the operation of No. 2 reactor in 1972, and persisted during 1973. A special procedure was developed for plugging the leaks using a remote welding machine but with the incidence of leaks continuing attempts were made to obtain a specimen of leaking tube by cutting through the boiler support tank to gain access. Eventually the fault was then traced to excessive relative motion between the tubes and support clips. Remedial work took seven months and was completed in December 1975. The start of the problem and the method of plugging the leaks is described. Details are given of the investigation leading to the obtaining and examination of a sample of leaking tube and the determination of the fault. Establishment of the cause as an unusual form of resonant vibration causing wear and fretting in clip-to-tube positions in the economiser region of the boiler is described in detail. The difficulties and accomplishments of the repair work are detailed. Finally the operation is looked at in retrospect and the experiences gained are summarised. (UK)

  11. Water-pirotube boiler: influence of its design in fabrication cost. Calderas de vapor pirotubulares: influencia del diseo en el coste de fabricacion

    Energy Technology Data Exchange (ETDEWEB)

    Latre Durso, F.

    1993-01-01

    Design of water-tube boiler and its cost is analyzed. Adequated combination of gases velocity, size of tubes, gases temperature, geometric configuration, etc will give a best product with quality prize relation. (Author)

  12. Optimising boiler performance.

    Science.gov (United States)

    Mayoh, Paul

    2009-01-01

    Soaring fuel costs continue to put the squeeze on already tight health service budgets. Yet it is estimated that combining established good practice with improved technologies could save between 10% and 30% of fuel costs for boilers. Paul Mayoh, UK technical manager at Spirax Sarco, examines some of the practical measures that healthcare organisations can take to gain their share of these potential savings.

  13. Computational Modeling and Assessment Of Nanocoatings for Ultra Supercritical Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Gandy, David W. [Electric Power Research Institute, Inc., Palo Alto, CA (United States); Shingledecker, John P. [Electric Power Research Institute, Inc., Palo Alto, CA (United States)

    2011-05-11

    Coal-fired power plants are a significant part of the nation's power generating capacity, currently accounting for more than 55% of the country's total electricity production. Extending the reliable lifetimes of fossil fired boiler components and reducing the maintenance costs are essential for economic operation of power plants. Corrosion and erosion are leading causes of superheater and reheater boiler tube failures leading to unscheduled costly outages. Several types of coatings and weld overlays have been used to extend the service life of boiler tubes; however, the protection afforded by such materials was limited approximately one to eight years. Power companies are more recently focused in achieving greater plant efficiency by increasing steam temperature and pressure into the advanced-ultrasupercritical (A-USC) condition with steam temperatures approaching 760°C (1400°F) and operating pressures in excess of 35MPa (5075 psig). Unfortunately, laboratory and field testing suggests that the resultant fireside environment when operating under A-USC conditions can potentially cause significant corrosion to conventional and advanced boiler materials1-2. In order to improve reliability and availability of fossil fired A-USC boilers, it is essential to develop advanced nanostructured coatings that provide excellent corrosion and erosion resistance without adversely affecting the other properties such as toughness and thermal fatigue strength of the component material.

  14. On the design of residential condensing gas boilers

    Energy Technology Data Exchange (ETDEWEB)

    Naeslund, M.

    1997-02-01

    Two main topics are dealt with in this thesis. Firstly, the performance of condensing boilers with finned tube heat exchangers and premix burners is evaluated. Secondly, ways of avoiding condensate formation in the flue system are evaluated. In the first investigation, a transient heat transfer approach is used to predict performance of different boiler configurations connected to different heating systems. The smallest efficiency difference between heat loads and heating systems is obtained when the heat exchanger gives a small temperature difference between flue gases and return water, the heat transfer coefficient is low and the thermostat hysteresis is large. Taking into account heat exchanger size, the best boiler is one with higher heat transfer per unit area which only causes a small efficiency loss. The total heating cost at part load, including gas and electricity, has a maximum at the lowest simulated heat load. The heat supplied by the circulation heat pump is responsible for this. The second investigation evaluates methods of drying the flue gases. Reheating the flue gases in different ways and water removal in an adsorbent bed are evaluated. Reheating is tested in two specially designed boilers. The necessary reheating is calculated to approximately 100-150 deg C if an uninsulated masonry chimney is used. The tested boilers show that it is possible to design a proper boiler. The losses, stand-by and convective/radiative, must be kept at a minimum in order to obtain a high efficiency. 86 refs, 70 figs, 16 tabs

  15. Installations of SNCR on bark-fired boilers

    International Nuclear Information System (INIS)

    Hjalmarsson, A.K.; Hedin, K.; Andersson, Lars

    1997-01-01

    Experience has been collected from the twelve bark-fired boilers in Sweden with selective non catalytic reduction (SNCR) installations to reduce emissions of nitrogen oxides. Most of the boilers have slope grates, but there are also two boilers with cyclone ovens and two fluidized bed boilers. In addition to oil there are also possibilities to burn other fuel types in most boilers, such as sludge from different parts of the pulp and paper mills, saw dust and wood chips. The SNCR installations seems in general to be of simple design. In most installations the injection nozzles are located in existing holes in the boiler walls. The availability is reported to be good from several of the SNCR installations. There has been tube leakage in several boilers. The urea system has resulted in corrosion and in clogging of one oil burner. This incident has resulted in a decision not to use SNCR system with the present design of the system. The fuel has also caused operational problems with the SNCR system in several of the installations due to variations in the moisture content and often high moisture content in bark and sludge, causing temperature variations. The availability is presented to be high for the SNCR system at several of the plants, in two of them about 90 %. The results in NO x reduction vary between the installations depending on boiler, fuel and operation. The emissions are between 45 and 100 mg NO 2 /MJ fuel input and the NO x reduction rates are in most installations between 30 and 40 %, the lowest 20 and the highest 70 %. 13 figs, 3 tabs

  16. Development of Self-Powered Wireless-Ready High Temperature Electrochemical Sensors for In-Situ Corrosion Monitoring for Boiler Tubes in Next Generation Coal-based Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xingbo [West Virginia Univ., Morgantown, WV (United States)

    2015-06-30

    The key innovation of this project is the synergy of the high temperature sensor technology based on the science of electrochemical measurement and state-of-the-art wireless communication technology. A novel self-powered wireless high temperature electrochemical sensor system has been developed for coal-fired boilers used for power generation. An initial prototype of the in-situ sensor demonstrated the capability of the wireless communication system in the laboratory and in a pilot plant (Industrial USC Boiler Setting) environment to acquire electrochemical potential and current signals during the corrosion process. Uniform and localized under-coal ash deposit corrosion behavior of Inconel 740 superalloy has been studied at different simulated coal ash hot corrosion environments using the developed sensor. Two typical potential noise patterns were found to correlate with the oxidation and sulfidation stages in the hot coal ash corrosion process. Two characteristic current noise patterns indicate the extent of the corrosion. There was a good correlation between the responses of electrochemical test data and the results from corroded surface analysis. Wireless electrochemical potential and current noise signals from a simulated coal ash hot corrosion process were concurrently transmitted and recorded. The results from the performance evaluation of the sensor confirm a high accuracy in the thermodynamic and kinetic response represented by the electrochemical noise and impedance test data.

  17. Fouling control in biomass boilers

    Energy Technology Data Exchange (ETDEWEB)

    Romeo, Luis M.; Gareta, Raquel [Centro de Investigacion de Recursos y Consumos Energeticos (CIRCE), Universidad de Zaragoza, Centro Politecnico Superior, Maria de Luna, 3, 50018 Zaragoza (Spain)

    2009-05-15

    One of the important challenges for biomass combustion in industrial applications is the fouling tendency and how it affects to the boiler performance. The classical approach for this question is to activate sootblowing cycles with different strategies to clean the boiler (one per shift, one each six hours..). Nevertheless, it has been often reported no effect on boiler fouling or an excessive steam consumption for sootblowing. This paper illustrates the methodology and the application to select the adequate time for activating sootblowing in an industrial biomass boiler. The outcome is a control strategy developed with artificial intelligence (Neural Network and Fuzzy Logic Expert System) for optimizing the biomass boiler cleaning and maximizing heat transfer along the time. Results from an optimize sootblowing schedule show savings up to 12 GWh/year in the case-study biomass boiler. Extra steam generation produces an average increase of turbine power output of 3.5%. (author)

  18. Mod increases AGR boiler output

    International Nuclear Information System (INIS)

    Jones, W.K.C.; Rider, G.; Taylor, D.E.

    1986-01-01

    During the commissioning runs of the first reactor units at Heysham I and Hartlepool Advanced Gas-cooled Reactors (AGRs), non-uniform temperature distributions were observed across individual boiler units which were more severe than those predicted from the design analysis. This article describes the re-orificing (referruling) of the boilers to overcome this problem. The referruling has reduced boiler sensitivity and resulted in an increase of load of 7 or 8%. (U.K.)

  19. Demonstration of coal reburning for cyclone boiler NO{sub x} control. Appendix, Book 1

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    Based on the industry need for a pilot-scale cyclone boiler simulator, Babcock Wilcox (B&W) designed, fabricated, and installed such a facility at its Alliance Research Center (ARC) in 1985. The project involved conversion of an existing pulverized coal-fired facility to be cyclone-firing capable. Additionally, convective section tube banks were installed in the upper furnace in order to simulate a typical boiler convection pass. The small boiler simulator (SBS) is designed to simulate most fireside aspects of full-size utility boilers such as combustion and flue gas emissions characteristics, fireside deposition, etc. Prior to the design of the pilot-scale cyclone boiler simulator, the various cyclone boiler types were reviewed in order to identify the inherent cyclone boiler design characteristics which are applicable to the majority of these boilers. The cyclone boiler characteristics that were reviewed include NO{sub x} emissions, furnace exit gas temperature (FEGT) carbon loss, and total furnace residence time. Previous pilot-scale cyclone-fired furnace experience identified the following concerns: (1) Operability of a small cyclone furnace (e.g., continuous slag tapping capability). (2) The optimum cyclone(s) configuration for the pilot-scale unit. (3) Compatibility of NO{sub x} levels, carbon burnout, cyclone ash carryover to the convection pass, cyclone temperature, furnace residence time, and FEGT.

  20. Design of Boiler Welding for Improvement of Lifetime and Cost Control.

    Science.gov (United States)

    Thong-On, Atcharawadi; Boonruang, Chatdanai

    2016-11-03

    Fe-2.25Cr-1Mo a widely used material for headers and steam tubes of boilers. Welding of steam tube to header is required for production of boiler. Heat affected zone of the weld can have poor mechanical properties and poor corrosion behavior leading to weld failure. The cost of material used for steam tube and header of boiler should be controlled. This study propose a new materials design for boiler welding to improve the lifetime and cost control, using tungsten inert gas (TIG) welding of Fe-2.25Cr-1Mo tube to carbon steel pipe with chromium-containing filler. The cost of production could be reduced by the use of low cost material such as carbon steel pipe for boiler header. The effect of chromium content on corrosion behavior of the weld was greater than that of the microstructure. The lifetime of the welded boiler can be increased by improvement of mechanical properties and corrosion behavior of the heat affected zone.

  1. Design of Boiler Welding for Improvement of Lifetime and Cost Control

    Directory of Open Access Journals (Sweden)

    Atcharawadi Thong-On

    2016-11-01

    Full Text Available Fe-2.25Cr-1Mo a widely used material for headers and steam tubes of boilers. Welding of steam tube to header is required for production of boiler. Heat affected zone of the weld can have poor mechanical properties and poor corrosion behavior leading to weld failure. The cost of material used for steam tube and header of boiler should be controlled. This study propose a new materials design for boiler welding to improve the lifetime and cost control, using tungsten inert gas (TIG welding of Fe-2.25Cr-1Mo tube to carbon steel pipe with chromium-containing filler. The cost of production could be reduced by the use of low cost material such as carbon steel pipe for boiler header. The effect of chromium content on corrosion behavior of the weld was greater than that of the microstructure. The lifetime of the welded boiler can be increased by improvement of mechanical properties and corrosion behavior of the heat affected zone.

  2. Workshop proceedings: U-bend tube cracking in steam generators

    Science.gov (United States)

    Shoemaker, C. E.

    1981-06-01

    A design to reduce the rate of tube failure in high pressure feedwater heaters, a number of failed drawn and stress relieved Monel 400 U-bend tubes removed from three high pressure feedwater heaters was examined. Steam extracted from the turbine is used to preheat the boiler feedwater in fossil fuel fired steam plants to improve thermal efficiency. This is accomplished in a series of heaters between the condenser hot well and the boiler. The heaters closest to the boiler handle water at high pressure and temperature. Because of the severe service conditions, high pressure feedwater heaters are frequently tubed with drawn and stress relieved Monel 400.

  3. A Flue Gas Tube for Thermoelectric Generator

    DEFF Research Database (Denmark)

    2013-01-01

    The invention relates to a flue gas tube (FGT) (1) for generation of thermoelectric power having thermoelectric elements (8) that are integrated in the tube. The FTG may be used in combined heat and power (CHP) system (13) to produce directly electricity from waste heat from, e.g. a biomass boiler...

  4. Application of composite tubes in power plants

    International Nuclear Information System (INIS)

    Toernblom, H.; Egnell, L.; Gullberg, R.

    1975-01-01

    Composite tubes with metallurgical bond are now being used on an industrial scale in recovery boilers. Service trials in power plants are viewed and the possibilities to solve fireside corrosion problems in the boiler and superheater sections are discussed. The present and potential future application in nuclear power plants is summarized. A brief presentation of the manufacture and fabrication of composite tubes is made and specific material properties are discussed. Composite tubes are concluded to be an established product and a useful means of meeting conflicting material requirements under severe service conditions. (author)

  5. Successful experience with limestone and other sorbents for combustion of biomass in fluid bed power boilers

    Energy Technology Data Exchange (ETDEWEB)

    Coe, D.R. [LG& E Power Systems, Inc., Irvine, CA (United States)

    1993-12-31

    This paper presents the theoretical and practical advantages of utilizing limestone and other sorbents during the combustion of various biomass fuels for the reduction of corrosion and erosion of boiler fireside tubing and refractory. Successful experiences using a small amount of limestone, dolomite, kaolin, or custom blends of aluminum and magnesium compounds in fluid bed boilers fired with biomass fuels will be discussed. Electric power boiler firing experience includes bubbling bed boilers as well as circulating fluid bed boilers in commercial service on biomass fuels. Forest sources of biomass fuels fired include wood chips, brush chips, sawmill waste wood, bark, and hog fuel. Agricultural sources of biomass fuels fired include grape vine prunings, bean straw, almond tree chips, walnut tree chips, and a variety of other agricultural waste fuels. Additionally, some urban sources of wood fuels have been commercially burned with the addition of limestone. Data presented includes qualitative and quantitative analyses of fuel, sorbent, and ash.

  6. Improved nuclear boiler

    International Nuclear Information System (INIS)

    Pierart, Robert.

    1980-01-01

    The improved nuclear boiler concerned in this invention is of the kind comprising, inter alia, a nuclear reactor supported by a metallic structure and of which the vessel is at least enclosed in part by a casing acting as a protective containment integrated in this structure. It is essentially characterized in that this casing is fitted into and maintained in position in the metallic structure by removable locking devices which enable the casing to be withdrawn from the remainder of the structure. Hence, after the casing has been withdrawn or removed from the metallic structure, access to the reactor vessel is readily obtained for inspection and/or testing from without [fr

  7. Firetube boiler with high efficiency for producing saturated or superheated steam

    Energy Technology Data Exchange (ETDEWEB)

    Carosso, V J; Carosso, J Y

    1976-10-07

    This boiler for producing saturated or super-heated steam is to be manufactured in one piece or in units which can be assembled at site without skilled workers, at the factory. It is to have a high efficiency and dimensions which permit the transport of the completely assembled boiler by road transport. The relatively small water-steam vessel lies across the longitudinal axis of the boiler in the rear boiler space over a battery of preheater tubes. By these measures and by a very detailed and appropriately described rational arrangement of other parts, such as convection bundles, primary and secondary superheater, evaporation tubes, which form an 'evaporation shield', upper and lower longitudinal chambers with vertical connecting pipes of different crossections, the above mentioned condition for space requirement is fulfilled and a high efficiency should be achieved, but with considerable expense.

  8. Numerical simulation of a small-scale biomass boiler

    International Nuclear Information System (INIS)

    Collazo, J.; Porteiro, J.; Míguez, J.L.; Granada, E.; Gómez, M.A.

    2012-01-01

    Highlights: ► Simplified model for biomass combustion was developed. ► Porous zone conditions are used in the bed. ► Model is fully integrated in a commercial CFD code to simulate a small scale pellet boiler. ► Pollutant emissions are well predicted. ► Simulation provides extensive information about the behaviour of the boiler. - Abstract: This paper presents a computational fluid dynamic simulation of a domestic pellet boiler. Combustion of the solid fuel in the burner is an important issue when discussing the simulation of this type of system. A simplified method based on a thermal balance was developed in this work to introduce the effects provoked by pellet combustion in the boiler simulation. The model predictions were compared with the experimental measurements, and a good agreement was found. The results of the boiler analysis show that the position of the water tubes, the distribution of the air inlets and the air infiltrations are the key factors leading to the high emission levels present in this type of system.

  9. A study by simulation of dynamic instability in boilers using the NUMEL/DYMEL suite of programmes

    International Nuclear Information System (INIS)

    Jeffries, T.O.

    1985-01-01

    Tube-to-tube instability in a once through sodium heated boiler has been studied using the finite difference model developed by the CEGB and embodied in the NUMEL and DYMEL compute codes. The method used was to simulate the boiler and then carry out frequency response tests, as one would on a real boiler. The advantages of using the simulation model compared with using the real system are the ease with which experiments may be performed and the ease of access to a wide range of parameters which could only be obtained approximately, if at all, from a real boiler. The advantage is that validation of the model is only approximate though in the case of sodium heated boilers, conditions are similar to those in electrically heated rigs used for validation. The study led to an understanding of how such a boiler should be operated to avoid tube-to-tube instability and with the detailed temperature profiles available from NUMEL it was possible to develop existing theory to predict boiler transfer functions similar to those observed in the frequency response tests. (author)

  10. B and W model boiler tests: effect of temperature on IGA rate. Initial and post-1878 operating conditions of the model boilers

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    The Babcock and Wilcox (B and W) model boiler operated with 10 ppm weekly injections of NaOH for 41,900 hours (4.8 years). The model boiler operating conditions are given. Tube No. 24 failed by caustic intergranular attack/stress corrosion cracking (IGA/SCC) at the steam-water zone. IGA defect depths on tube 24 is compared at different locations, which also have different temperature conditions. The specific locations are: steam/water zone, drilled baffle plate, and lower tube sheet crevice. In all locations caustic will concentrate (although to different concentration levels). Nevertheless, an effect of temperature on IGA rate can be estimated. The degree of attack relative to the location and environment is shown. SEM fractographs illustrate the completely intergranular failure of Tube 24. A summary of the estimated results is presented. These results show the estimated IGA rate as a function of primary/secondary temperature and estimated caustic concentration. Details of the failure analysis of the model boiler can be found in the final report Destructive Examination of Babcock and Wilcox's Model Boiler for Intergranular Attack (IGA) on Tubes, EPRI S302-6, J.L.; Barna and L.W. Sarver

  11. Market review. Pellet wood gasification boiler / combination boiler. 8. ed.; Marktuebersicht. Scheitholzvergaser-/Kombikessel

    Energy Technology Data Exchange (ETDEWEB)

    Uth, Joern

    2012-01-15

    In the market review under consideration on pellet wood gasification boilers and combination boilers, the Federal Ministry of Food, Agriculture and Consumer Protection (Bonn, Federal Republic of Germany) reports on planning and installation of wood-fired heating systems, recommendations regarding to the technical assessment of boiler systems, buffers/combination boilers, prices of pellet wood gasification boilers, data sheets of the compared pellet wood gasification boilers, pellet wood combination boilers, prices of pellet wood combination boilers, data sheets of the compared pellet wood gasification boilers, list of providers.

  12. Pellet wood gasification boiler / Combination boiler. Market review. 7. ed.; Scheitholzvergaser-/Kombikessel. Marktuebersicht

    Energy Technology Data Exchange (ETDEWEB)

    Uth, Joern

    2010-08-15

    In the market review under consideration on pellet wood gasification boilers and combination boilers, the Federal Ministry of Food, Agriculture and Consumer Protection (Bonn, Federal Republic of Germany) report on planning and installation of wood-fired heating systems, recommendations regarding to the technical assessment of boiler systems, buffers/combination boilers, prices of pellet wood gasification boilers, data sheets of the compared pellet wood gasification boilers, pellet wood combination boilers, prices of pellet wood combination boilers, data sheets of the compared pellet wood gasification boilers, list of providers.

  13. Occurrence and prevention of enhanced oxide deposition in boiler flow control orifices

    International Nuclear Information System (INIS)

    Woolsey, I.S.; Thomas, D.M.; Garbett, K.; Bignold, G.J.

    1989-10-01

    Once-through boilers, such as those of the AGRs, incorporate flow control orifices at the boiler inlet to ensure a satisfactory flow distribution and stability in the parallel flow paths of the boiler. Deposition of corrosion products in the flow control orifice leads to changes in the orifice pressure loss characteristics, which could lead to problems of flow maldistribution within the boiler, and any adverse consequences resulting from this, such as tube overheating. To date, AGR boiler inlet orifices have not suffered significant fouling due to corrosion products in the boiler feedwater. However, oxide deposition in orifices has been observed in other plants, and in experimental loops operating under conditions very similar to those at inlet to AGR boilers. The lack of deposition in AGR flow control orifices is therefore somewhat surprising. This Report describes studies carried out to examine the factors controlling oxide deposition in flow control orifices, the intention of the work being to explain why deposition has not occurred in AGR boilers to date, and to provide means of preventing deposition in the future should this prove necessary. (author)

  14. CCD camera eases the control of a soda recovery boiler; CCD-kamera helpottaa soodakattilan valvontaa

    Energy Technology Data Exchange (ETDEWEB)

    Kinnunen, L.

    2001-07-01

    Fortum Technology has developed a CCD firebox camera, based on semiconductor technology, enduring hard conditions of soda recovery boiler longer than traditional cameras. The firebox camera air- cooled and the same air is pressed over the main lens so it remains clean despite of the alkaline liquor splashing around in the boiler. The image of the boiler is transferred through the main lens, image transfer lens and a special filter, mounted inside the camera tube, into the CCD camera. The first CCD camera system has been in use since 1999 in Sunila pulp mill in Kotka, owned by Myllykoski Oy and Enso Oyj. The mill has two medium-sized soda recovery boilers. The amount of black liquor, formed daily, is about 2000 tons DS, which is more than enough for the heat generation. Even electric power generation exceeds sometimes the demand, so the surplus power can be sold out. Black liquor is sprayed inside the soda recovery boiler with high pressure. The liquor form droplets in the boiler, the temperature of which is over 1000 deg C. A full-hot pile is formed at the bottom of the boiler after burning. The size and shape of the pile effect on the efficiency and the emissions of the boiler. The camera has operated well.

  15. A study on the boiler efficiency influenced by the boiler operation parameter in fossil power plant

    International Nuclear Information System (INIS)

    Kwon, Y. S.; Suh, J. S.

    2002-01-01

    The main reason to analyze the boiler operation parameter in fossil power plant is to increase boiler high efficiency and energy saving movement in the government. This study intends to have trend and analyze the boiler efficiency influenced by the boiler parameter in sub-critical and super-critical type boiler

  16. 49 CFR 230.47 - Boiler number.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Boiler number. 230.47 Section 230.47..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.47 Boiler number. (a) Generally. The builder's number of the boiler, if known, shall...

  17. 30 CFR 77.413 - Boilers.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Boilers. 77.413 Section 77.413 Mineral... Mechanical Equipment § 77.413 Boilers. (a) Boilers shall be equipped with guarded, well-maintained water... the gages shall be kept clean and free of scale and rust. (b) Boilers shall be equipped with automatic...

  18. 30 CFR 56.13030 - Boilers.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Boilers. 56.13030 Section 56.13030 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13030 Boilers. (a) Fired pressure vessels (boilers) shall be equipped with water level gauges, pressure gauges...

  19. 30 CFR 57.13030 - Boilers.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Boilers. 57.13030 Section 57.13030 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13030 Boilers. (a) Fired pressure vessels (boilers) shall be equipped with water level gauges, pressure...

  20. Two phase flow problems in power station boilers

    International Nuclear Information System (INIS)

    Firman, E.C.

    1974-01-01

    The paper outlines some of the waterside thermal and hydrodynamic phenomena relating to design and operation of large boilers in central power stations. The associated programme of work is described with an outline of some results already obtained. By way of introduction, the principal features of conventional and nuclear drum boilers and once-through nuclear heat exchangers are described in so far as they pertain to this area of work. This is followed by discussion of the relevant physical phenomena and problems which arise. For example, the problem of steam entrainment from the drum into the tubes connecting it to the furnace wall tubes is related to its effects on circulation and possible mechanisms of tube failure. Other problems concern the transient associated with start-up or low load operation of plant. The requirement for improved mathematical representation of steady and dynamic performance is mentioned together with the corresponding need for data on heat transfer, pressure loss, hydrodynamic stability, consequences of deposits, etc. The paper concludes with reference to the work being carried out within the C.E.G.B. in relation to the above problems. The facilities employed and the specific studies being made on them are described: these range from field trials on operational boilers to small scale laboratory investigations of underlying two phase flow mechanisms and include high pressure water rigs and a freon rig for simulation studies

  1. CFB boilers in multifuel application

    International Nuclear Information System (INIS)

    Goral, D.; Krzton, B.

    2007-01-01

    Fuel flexibility characteristic for CFB boilers plays an important rule in industrial and utility size applications. Possibility to use wider range of fuels that has been long time considered as by-products or wastes and possibility to design boilers able to operate with alternative fuels is an important factor that improves fuel delivery security and plant economy. Presented article is based on similar publications that present Foster Wheeler's experience in design and delivery of the CFB boilers for wide range of coals and cofiring by- products of crude oil refining and coal processing. Aspects of biomass cofiring will be also presented. (author)

  2. 46 CFR 61.05-10 - Boilers in service.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Boilers in service. 61.05-10 Section 61.05-10 Shipping... INSPECTIONS Tests and Inspections of Boilers § 61.05-10 Boilers in service. (a) Each boiler, including superheater, reheater, economizer, auxiliary boiler, low-pressure heating boiler, and unfired steam boiler...

  3. ENERGY STAR Certified Commercial Boilers

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 1.0 ENERGY STAR Program Requirements for Commercial Boilers that are effective as of...

  4. Hybrid model of steam boiler

    International Nuclear Information System (INIS)

    Rusinowski, Henryk; Stanek, Wojciech

    2010-01-01

    In the case of big energy boilers energy efficiency is usually determined with the application of the indirect method. Flue gas losses and unburnt combustible losses have a significant influence on the boiler's efficiency. To estimate these losses the knowledge of the operating parameters influence on the flue gases temperature and the content of combustible particles in the solid combustion products is necessary. A hybrid model of a boiler developed with the application of both analytical modelling and artificial intelligence is described. The analytical part of the model includes the balance equations. The empirical models express the dependence of the flue gas temperature and the mass fraction of the unburnt combustibles in solid combustion products on the operating parameters of a boiler. The empirical models have been worked out by means of neural and regression modelling.

  5. Boiler-turbine life extension

    Energy Technology Data Exchange (ETDEWEB)

    Natzkov, S. [TOTEMA, Ltd., Sofia (Bulgaria); Nikolov, M. [CERB, Sofia (Bulgaria)

    1995-12-01

    The design life of the main power equipment-boilers and turbines is about 105 working hours. The possibilities for life extension are after normatively regulated control tests. The diagnostics and methodology for Boilers and Turbines Elements Remaining Life Assessment using up to date computer programs, destructive and nondestructive control of metal of key elements of units equipment, metal creep and low cycle fatigue calculations. As well as data for most common damages and some technical decisions for elements life extension are presented.

  6. Deposit Shedding in Biomass-fired Boilers: Shear Adhesion Strength Measurements

    DEFF Research Database (Denmark)

    Laxminarayan, Yashasvi; Jensen, Peter Arendt; Wu, Hao

    2016-01-01

    . Therefore, timely removal of ash deposits is essential for optimal boiler operation. In order to improve the understanding of deposit shedding in boilers, this study investigates the shear adhesion strength of biomass ash deposits on superheater tubes. Artificial biomass ash deposits were prepared...... on superheater tubes and sintered in an oven at temperatures up to 1000 °C. Subsequently, the deposits were sheared off by an electrically controlled arm, and the corresponding adhesion strength was measured. The results reveal the effect of temperature, deposit composition, sintering duration, and steel type...... on the adhesion strength....

  7. 77 FR 32508 - Circular Welded Carbon Steel Pipes and Tubes From Turkey: Notice of Preliminary Results of...

    Science.gov (United States)

    2012-06-01

    ... pipe, oil country tubular goods, boiler tubing, cold- drawn or cold-rolled mechanical tubing, pipe and... in the marketing process and selling functions along the chain of distribution between the producer...

  8. CFD Simulation On CFBC Boiler

    Directory of Open Access Journals (Sweden)

    Amol S. Kinkar

    2015-02-01

    Full Text Available Abstract Heavy industrialization amp modernization of society demands in increasing of power cause to research amp develop new technology amp efficient utilization of existing power units. Variety of sources are available for power generation such as conventional sources like thermal hydro nuclear and renewable sources like wind tidal biomass geothermal amp solar. Out of these most common amp economical way for producing the power is by thermal power stations. Various industrial boilers plays an important role to complete the power generation cycle such as CFBC Circulating Fluidized Bed Combustion FBC Fluidized Bed Combustion AFBC Atmospheric Fluidized Bed Combustion Boiler CO Boiler RG amp WHR Boiler Waster heat recovery Boiler. This paper is intended to comprehensively give an account of knowledge related to refractory amp its failure in CFBC boiler with due effect of flue gas flow during operation on refractory by using latest technology of CAD Computer aided Design amp CAE Computer aided Engineering. By conceptual application of these technology the full scale model is able to analyze in regards the flow of flue gas amp bed material flow inside the CFBC loop via CFD Computational Fluid Dynamics software. The results obtained are helpful to understand the impact of gas amp particles on refractory in different areas amp also helped to choose suitable refractory material in different regions.

  9. Erosion-corrosion behaviour of Ni-based superalloy Superni-75 in the real service environment of the boiler

    Energy Technology Data Exchange (ETDEWEB)

    Sidhu, T.S.; Prakash, S.; Agrawal, R.D.; Bhagat, R. [Shaheed Bhagat Singh College of Engineering & Technology, Ferozepur (India)

    2009-04-15

    The super-heater and re-heater tubes of the boilers used in thermal power plants are subjected to unacceptable levels of surface degradation by the combined effect of erosion-corrosion mechanism, resulting in the tube wall thinning and premature failure. The nickel-based superalloys can be used as boiler tube materials to increase the service life of the boilers, especially for the new generation ultra-supercritical boilers. The aim of the present investigation is to evaluate the erosion-corrosion behaviour of Ni-based superalloy Superni-75 in the real service environment of the coal-fired boiler of a thermal power plant. The cyclic experimental study was performed for 1000 h in the platen superheater zone of the coal-fired boiler where the temperature was around 900{sup o}C. The corrosion products have been characterized with respect to surface morphology, phase composition and element concentration using the combined techniques of X-ray diffractometry (XRD), scanning electron microscopy/energy-dispersive analysis (SEM/EDAX) and electron probe micro analyser (EPMA). The Superni-75 performed well in the coal-fired boiler environment, which has been attributed mainly to the formation of a thick band of chromium in scale due to selective oxidation of the chromium.

  10. Thermal–hydraulic calculation and analysis of a 600 MW supercritical circulating fluidized bed boiler with annular furnace

    International Nuclear Information System (INIS)

    Wang, Long; Yang, Dong; Shen, Zhi; Mao, Kaiyuan; Long, Jun

    2016-01-01

    Highlights: • Non-linear model of supercritical CFB boiler with annular furnace is developed. • Many empirical correlations are used to solve the model. • The thermal–hydraulic characteristics of boiler are analyzed. • The results show that the design of the annular furnace is reasonable. - Abstract: The development of supercritical Circulating Fluidized Bed (CFB) boiler has great economic and environmental value. An entirely new annular furnace structure with outer and inner ring sidewalls for supercritical CFB boiler has been put forward by Institute of Engineering Thermophysics (IET), Chinese Academy of Sciences and Dongfang Boiler Group Co., Ltd. (DBC). Its outer and inner ring furnace structure makes more water walls arranged and reduces furnace height availably. In addition, compared with other additional evaporating heating surface structures such as mid-partition and water-cooled panels, the integrative structure can effectively avoid the bed-inventory overturn and improve the penetrability of secondary air. The conditions of the 600 MW supercritical CFB boiler including capability, pressure and mass flux are harsh. In order to insure the safety of boiler operation, it is very necessary to analyze the thermal–hydraulic characteristics of water-wall system. The water-wall system with complicated pipe arrangement is regarded as a network consisting of series-parallel circuits, pressure nodes and linking circuits, which represent vertical water-wall tubes, different headers and linking tubes, respectively. Based on the mass, momentum and energy conservation, a mathematical model is built, which consists of some simultaneous nonlinear equations. The mass flux in circuits, pressure drop between headers, outer vapor temperature of water-wall system and metal temperature data of tubes at the boiler maximum continuous rating (BMCR), 75% BMCR and 30% BMCR loads are obtained by solving the mathematical model. The results show that the vertical water

  11. Boiler using combustible fluid

    Science.gov (United States)

    Baumgartner, H.; Meier, J.G.

    1974-07-03

    A fluid fuel boiler is described comprising a combustion chamber, a cover on the combustion chamber having an opening for introducing a combustion-supporting gaseous fluid through said openings, means to impart rotation to the gaseous fluid about an axis of the combustion chamber, a burner for introducing a fluid fuel into the chamber mixed with the gaseous fluid for combustion thereof, the cover having a generally frustro-conical configuration diverging from the opening toward the interior of the chamber at an angle of between 15/sup 0/ and 55/sup 0/; means defining said combustion chamber having means defining a plurality of axial hot gas flow paths from a downstream portion of the combustion chamber to flow hot gases into an upstream portion of the combustion chamber, and means for diverting some of the hot gas flow along paths in a direction circumferentially of the combustion chamber, with the latter paths being immersed in the water flow path thereby to improve heat transfer and terminating in a gas outlet, the combustion chamber comprising at least one modular element, joined axially to the frustro-conical cover and coaxial therewith. The modular element comprises an inner ring and means of defining the circumferential, radial, and spiral flow paths of the hot gases.

  12. High-Temperature Graphitization Failure of Primary Superheater Tube

    Science.gov (United States)

    Ghosh, D.; Ray, S.; Roy, H.; Mandal, N.; Shukla, A. K.

    2015-12-01

    Failure of boiler tubes is the main cause of unit outages of the plant, which further affects the reliability, availability and safety of the unit. So failure analysis of boiler tubes is absolutely essential to predict the root cause of the failure and the steps are taken for future remedial action to prevent the failure in near future. This paper investigates the probable cause/causes of failure of the primary superheater tube in a thermal power plant boiler. Visual inspection, dimensional measurement, chemical analysis, metallographic examination and hardness measurement are conducted as the part of the investigative studies. Apart from these tests, mechanical testing and fractographic analysis are also conducted as supplements. Finally, it is concluded that the superheater tube is failed due to graphitization for prolonged exposure of the tube at higher temperature.

  13. Dynamic Simulation of the Water-steam System in Once-through Boilers - Sub-critical Power Boiler Case -

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seongil; Choi, Sangmin [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2017-05-15

    The dynamics of a water-steam system in a once-through boiler was simulated based on the physics-based modeling approach, representing the system in response to large load change or scale disturbance simulations. The modeling considered the mass, energy conservation, and momentum equation in the water pipe and the focus was limited to the sub-critical pressure region. An evaporator tube modeling was validated against the reference data. A simplified boiler system consisting of economizer, evaporator, and superheater was constructed to match a 500 MW power boiler. The dynamic response of the system following a disturbance was discussed along with the quantitative response characteristics. The dynamic response of the boiler system was further evaluated by checking the case of an off-design point operation of the feedwater-to-fuel supply ratio. The results re-emphasized the significance of controlling the feedwater-to-fuel supply ratio and additional design requirements of the water-steam separator and spray attemperator.

  14. Dynamic Simulation of the Water-steam System in Once-through Boilers - Sub-critical Power Boiler Case -

    International Nuclear Information System (INIS)

    Kim, Seongil; Choi, Sangmin

    2017-01-01

    The dynamics of a water-steam system in a once-through boiler was simulated based on the physics-based modeling approach, representing the system in response to large load change or scale disturbance simulations. The modeling considered the mass, energy conservation, and momentum equation in the water pipe and the focus was limited to the sub-critical pressure region. An evaporator tube modeling was validated against the reference data. A simplified boiler system consisting of economizer, evaporator, and superheater was constructed to match a 500 MW power boiler. The dynamic response of the system following a disturbance was discussed along with the quantitative response characteristics. The dynamic response of the boiler system was further evaluated by checking the case of an off-design point operation of the feedwater-to-fuel supply ratio. The results re-emphasized the significance of controlling the feedwater-to-fuel supply ratio and additional design requirements of the water-steam separator and spray attemperator.

  15. Chemical and hydrothermal studies on once through boilers using a full scale replica

    International Nuclear Information System (INIS)

    Penfold, D.; Gill, G.M.; Greene, J.C.; Harrison, G.S.; Walker, M.A.

    1987-01-01

    The paper describes the scope of research work carried out on once through boilers on the test rig at Wythenshawe, United Kingdom. The latter rig was designed and built to replicate the chemical, metallurgical and hydrothermal conditions on single tube test sections of Heysham 1 (AGR) and Wylfa (Magnox) boilers. A description is given of the rig, along with the facilities for obtaining the research data. Research studies on the once through boilers include: Heysham 1 boiler inlet, oxygen stress corrosion risk in post trip operation, Wylfa two phase erosion-corrosion risk in post trip operation, Wylfa two phase erosion-corrosion, dryout phenomena in a helical coil, and heat transfer co-efficients. (UK)

  16. New controls spark boiler efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Engels, T. (Monsanto, University Park, IL (United States))

    1993-09-01

    Monsanto's NutraSweet plant in University Park, IL, produces aspartame, the patented NutraSweet artificial sweetener product. Until recently, boiler control was managed by a '60s-era Fireye jackshaft system in which air and natural gas were mechanically linked with an offset to compensate for oxygen trim. The interlocking devices on the Fireye system were becoming obsolete, and the boiler needed a new front end retrofitted for low emissions. In order to improve boiler control efficiency, we decided to modernize and automate the entire boiler control system. We replaced the original jackshaft system, and installed a Gordon-Piet burner system, including gas valves, air dampers, blowers, and burner. The upgrade challenges included developing a control strategy and selecting and implementing a process control system. Since our plant has standardized on the PROVOX process management information system from Fisher Controls (now Fisher-Rosemount Systems) to support most of our process, it was a natural and logical choice for boiler controls as well. 2 figs.

  17. The early operation of the helical once-through boilers at Heysham 1 and Hartlepool

    International Nuclear Information System (INIS)

    Mathews, A.J.

    1988-01-01

    The Heysham 1 and Hartlepool AGR Reactors are equipped with 'pod' boilers set into the walls of the Pre-stressed Concrete Pressure Vessel. Each Reactor unit has eight pod boilers, which are of a somewhat unique single pressure, once through, helically wound type incorporating a reheater. The pods are provided with a limited amount of strain gauge and thermocouple instrumentation concentrated mainly in two specially instrumented boilers at each site. During Commissioning prior to power raising, extensive noise and vibration tests utilising the special attain gauge instrumented boilers, gave encouraging results. This has led to an increase in coolant gas mass flow of 5% above the design level. Following power raising in 1983 and 1984, detailed boiler performance testing, mainly using the special thermocouple instrumented boilers, showed that the actual behaviour differed from the computer design predictions. A major temperature tilt existed across the boiler tubes resulting in higher than predicted temperatures in the outer radius rows of tubes and the reverse situation in the inner tubes. The effect differed in magnitude between Hartlepool Reactor 1 and the other three Reactors probably due to construction differences. As a result output was initially limited to approximately 58% of design (380 MW (Generated)). A major programme of altering the flow control ferrules was carried out during the first statutory overhauls in 1985 and 1986. The initial results from Heysham 1 were not very encouraging (a gain of 70 MW(e)) but further computer model correlations led to revised patterns in Heysham and Hartlepool Reactor 2 which have since yielded improvements in output potential of up to 200 MW(e). The paper discusses the commissioning test results described above and describes the details of the extensive work carried out to achieve higher output. (author)

  18. Development of combined low-emissions burner devices for low-power boilers

    Science.gov (United States)

    Roslyakov, P. V.; Proskurin, Yu. V.; Khokhlov, D. A.

    2017-08-01

    Low-power water boilers are widely used for autonomous heat supply in various industries. Firetube and water-tube boilers of domestic and foreign manufacturers are widely represented on the Russian market. However, even Russian boilers are supplied with licensed foreign burner devices, which reduce their competitiveness and complicate operating conditions. A task of developing efficient domestic low-emissions burner devices for low-power boilers is quite acute. A characteristic property of ignition and fuel combustion in such boilers is their flowing in constrained conditions due to small dimensions of combustion chambers and flame tubes. These processes differ significantly from those in open combustion chambers of high-duty power boilers, and they have not been sufficiently studied yet. The goals of this paper are studying the processes of ignition and combustion of gaseous and liquid fuels, heat and mass transfer and NO x emissions in constrained conditions, and the development of a modern combined low-emissions 2.2 MW burner device that provides efficient fuel combustion. A burner device computer model is developed and numerical studies of its operation on different types of fuel in a working load range from 40 to 100% of the nominal are carried out. The main features of ignition and combustion of gaseous and liquid fuels in constrained conditions of the flame tube at nominal and decreased loads are determined, which differ fundamentally from the similar processes in steam boiler furnaces. The influence of the burner devices design and operating conditions on the fuel underburning and NO x formation is determined. Based on the results of the design studies, a design of the new combined low-emissions burner device is proposed, which has several advantages over the prototype.

  19. The application of TIG-welding to the manufacture of modern boiler units. Chapter 3

    International Nuclear Information System (INIS)

    Dick, N.T.

    1978-01-01

    Stringent weld acceptance standards are necessary in nuclear installations. Mechanised TIG-welding is being used exclusively in the manufacture of the boiler pods for the Hartlepool and Heysham nuclear generating stations. The choice of a TIG welding process is discussed. Reliability, access, welding position, tube dimensions and weld profile were important as was the desirability of having ferrite control because in the austenitic stainless steel used, the acceptance standard does not permit microfissuring. Development of the technique and production equipment and conditions are given for tube butt welding, tube-to-tubeplate bore welding and tube-to-tubeplate face welding in AGR applications. (U.K.)

  20. Application of newly developed heat resistant materials for USC boilers

    International Nuclear Information System (INIS)

    Sato, T.; Tamura, K.; Fukuda, Y.; Matsuda, J.

    2004-01-01

    This paper describes the research on the development and improvement of new high strength heat resistant steels such as SUPER304H (18Cr-9Ni-3Cu-Nb-N), NF709 (20Cr-25Ni-1.5Mo-Nb-Ti-N) and HR3C (25Cr-20Ni-Nb-N) as boiler tube, and NF616 (9Cr-0.5Mo-1.8W-Nb-V) and HCM12A (11Cr-0.4Mo-2W-Nb-V-Cu) as thick section pipe. The latest manufacturing techniques applied for these steels are introduced. In addition the high temperature strength of Alloy617 (52Ni-22Cr-13Co-9Mo-Ti-Al) that is one of the candidate materials for the next generation 700 □ USC boilers is described. (orig.)

  1. Multi-unit shutdown due to boiler feedwater chemical excursion

    International Nuclear Information System (INIS)

    Diebel, M.E.

    1991-01-01

    Ontario Hydro's Bruce Nuclear Generating Station 'B' consists of four 935 W CANDU units located on the east shore of Lake Huron in the province of Ontario, Canada. On July 25 and 26, 1989 three of the four operating units were shutdown due to boiler feedwater chemical excursions initiated by a process upset in the Water Treatment Plant that provides demineralized make-up water to all four units. The chemicals that escaped from an ion exchange vessel during a routine regeneration very quickly spread through the condensate make-up system and into the boiler feedwater systems. This resulted in boiler sulfate levels exceeding shutdown limits. A total of 260 GWH of electrical generation was unexpectedly made unavailable to the grid at a time of peak seasonal demand. This event exposed several unforeseen deficiencies and vulnerabilities in the automatic demineralized water make-up quality protection scheme, system designs, operating procedures and the ability of operating personnel to recognize and appropriately respond to such an event. The combination of these factors contributed towards turning a minor system upset into a major multi-unit shutdown. This paper provides the details of the actual event initiation in the Water Treatment Plant and describes the sequence of events that led to the eventual shutdown of three units and near shutdown of the fourth. The design inadequacies, procedural deficiencies and operating personnel responses and difficulties are described. The process of recovering from this event, the flushing out of system piping, boilers and the feedwater train is covered as well as our experiences with setting up supplemental demineralized water supplies including trucking in water and the use of rental trailer mounted demineralizing systems. System design, procedural and operational changes that have been made and that are still being worked on in response to this event are described. The latest evidence of the effect of this event on boiler tube

  2. FY 1999 achievement report on the development of high performance boilers. R and D on high performance industrial furnaces, etc.; 1999 nendo koseino boiler no kaihatsu ni kansuru kenkyu seika hokokusho. Koseino kogyoro nado ni kansuru kenkyu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    This project started in FY 1993 to survey the actual state of industrial use boilers. Based on the results of the survey, in fiscal 1995, 1996 and 1997, no improvement of the present technology which has limits, but the development was made of the oxygen combustion and element technology which are factors for heightening boiler performance with a new idea first in the world. In fiscal 1998, a target for the overall thermal efficiency of 105% was settled by testing a pilot plant where the element technology was integrated into the small once-through boiler, flue/smoke tube boiler, water tube boiler, etc. In fiscal 1999, the target of the overall thermal efficiency of boiler was reached by a pilot plant test to clarify combustion characteristics, heat transfer characteristics, environmental characteristics, etc. Further, effects of energy saving were increased by the adoption method of oxygen supply equipment. Concretely, an overall boiler efficiency of 105.73% exceeding the targeted value of 105% was achieved at a pilot plant of actual scale, by concentrating the results of each of the element technologies such as 'oxygen combustion,' 'condensation type flue gas heat exchanger,' 'high performance combustion control device,' and 'rapid rotating auxiliary machine.' (NEDO)

  3. Sootblowing optimization for improved boiler performance

    Science.gov (United States)

    James, John Robert; McDermott, John; Piche, Stephen; Pickard, Fred; Parikh, Neel J.

    2012-12-25

    A sootblowing control system that uses predictive models to bridge the gap between sootblower operation and boiler performance goals. The system uses predictive modeling and heuristics (rules) associated with different zones in a boiler to determine an optimal sequence of sootblower operations and achieve boiler performance targets. The system performs the sootblower optimization while observing any operational constraints placed on the sootblowers.

  4. Optimizing the Integrated Design of Boilers - Simulation

    DEFF Research Database (Denmark)

    Sørensen, K.; Karstensen, C.; Condra, T.

    2004-01-01

    Boilers can be considered as consisting of three main components: (i) the pressure part, (ii) the burner and (iii) the control system. To be able to develop the boilers of the future (i.e. the boilers with the lowest emissions, the highest efciency, the best dynamic performance etc.) it is import...

  5. INDUSTRIAL BOILER RETROFIT FOR NOX CONTROL: COMBINED SELECTIVE NONCATALYTIC REDUCTION AND SELECTIVE CATALYTIC REDUCTION

    Science.gov (United States)

    The paper describes retrofitting and testing a 590 kW (2 MBtu/hr), oil-fired, three-pass, fire-tube package boiler with a combined selective noncatalytic reduction (SNCR) and selective catalytic reduction (SCR) system. The system demonstrated 85% nitrogen oxides (NOx) reduction w...

  6. MULTIPLE LINEAR REGRESSION ANALYSIS FOR PREDICTION OF BOILER LOSSES AND BOILER EFFICIENCY

    OpenAIRE

    Chayalakshmi C.L

    2018-01-01

    MULTIPLE LINEAR REGRESSION ANALYSIS FOR PREDICTION OF BOILER LOSSES AND BOILER EFFICIENCY ABSTRACT Calculation of boiler efficiency is essential if its parameters need to be controlled for either maintaining or enhancing its efficiency. But determination of boiler efficiency using conventional method is time consuming and very expensive. Hence, it is not recommended to find boiler efficiency frequently. The work presented in this paper deals with establishing the statistical mo...

  7. Life extension of MAPS-2 by replacement of boiler hairpin type heat exchangers

    International Nuclear Information System (INIS)

    Tripathi, J.C.; Rastogi, S.K.; Rastogi, A.K.

    2006-01-01

    The steam generating equipment in MAPS-1 and 2 are Hairpin type comprises of eight boiler assemblies arranged in two banks of four boilers each. Each hairpin type heat exchangers consist of 195 Monel-400 tubes of 12.7 mm OD x 1.24 mm WT. One boiler assembly consists of eleven inverted U type heat exchangers (called hairpin type heat exchangers) mounted in parallel on inlet and outlet heavy water manifolds and connected to steam drum through individual short riser. Heavy water flows through these tubes where as feed water enters the shell at the bottom of one leg called pre-heat leg. After commissioning of MAPS-2 in 1985, five hairpins of MAPS-2 developed leak during the course of operation by the year 1999. Absence of physical access for health assessment of steam generator tube and lack of provision for tube sheet cleaning to remove the deposits on feed water side had caused pile and resulted in tube failures by under deposit pitting corrosion. All the 88 hairpins of MAPS-2 were replaced to extend the plant life when MAPS-2 was taken out of grid for En-masse Coolant Channel Replacement job (EMCCR) in the year 2001 - 03. The long shutdown of MAPS units for EMCCR was considered to be cost effective since unscheduled plant shut downs on account of tube leaks could be avoided. (author)

  8. Tube leak detector

    International Nuclear Information System (INIS)

    Morita, Bunji; Takamura, Koichi; Matsuda, Shigehiro; Kiyosawa, Shun-ichi; Asami, Toru; Yamada, Hiroshi; Naruse, Shin-ichi.

    1995-01-01

    The device of the present invention detects occurrence of leakage in a steam generator, a steam heating tube, or a heat exchanger of a nuclear power plant. Namely, an vibration sensor is disposed at the rear end of a rod-like supersonic resonance member. A node portion for the vibrations of the resonance member is held by a holding member and attached to a wall surface of a can such as a boiler. With such a constitution, the resonance member is resonated by supersonic waves generated upon leakage of the tube. The vibrations are measured by the vibration sensor at the rear end. Presence of leakage is detected by utilizing one or more of resonance frequencies. Since the device adopts a resonance phenomenon, a conduction efficiency of the vibrations is high, thereby enabling to detect leakage at high sensitivity. In addition, the supersonic wave resonance member has its top end directly protruded into a pressure vessel such as a boiler by using a metal or a ceramic which is excellent in heat and pressure resistance. Accordingly, the sound of leak can be detected efficiently. (I.S.)

  9. Design of a small scale boiler package for testing high moisture content biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Proctor, Andrew

    2005-07-01

    This report presents the results of a project to design a prototype, small-scale boiler (0.88 MWth output) to enable clean and efficient combustion of high moisture content (>30%) biomass fuels. The boiler was based on an open bottom smoke tube design, modified to incorporate water tubes in the combustion chamber running from front to back. These were added to support refractory bricks to create an extra pass in the boiler combustion chamber such that the reflected heat from the refractory increased the rate of evaporation of moisture from the fuel. A chain grate stoker was employed. The combustion tests involved three biofuels: wood pellets with a low moisture content (8-10%) (to provide combustion rates for a commercially proven biofuel); wood chips from forestry waste with a 30-40% moisture content; and spent mushroom compost with 70-75% moisture. The tests on the wood chips required a number of modifications to the fuel feeding system and to the boiler in order to achieve limited success and the tests with the mushroom compost were unsuccessful due to the combination of the high moisture content and the fuel's low calorific value. Experience gained with the wood chips suggested a number of improvements for a future boiler design. As well as describing the experimental work and test results, the report offers an economic analysis (capital costs, fuel costs, running costs) of the scheme.

  10. A CFD study on the dust behaviour in a metallurgical waste-heat boiler

    Energy Technology Data Exchange (ETDEWEB)

    Yongxiang, Yang; Jokilaakso, A [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Materials Processing and Powder Metallurgy

    1998-12-31

    A waste-heat boiler forms an essential part for the treatment of high temperature flue-gases in most metallurgical processes. Flue-dust carried by the furnace off-gas has to be captured efficiently in the waste-heat boilers before entering the downstream gas purification equipment. Flue dust may accumulate and foul on the heat transfer surfaces such as tube-walls, narrow conjunctions between the boiler and the furnace uptake, and thus may cause smelter shutdown, and interrupt the production. A commercial CFD package is used as the major tool on modelling the dust flow and settling in the waste-heat boiler of an industrial copper flash smelter. In the presentation, dust settling behaviour is illustrated for a wide range of particle sizes, and dust capture efficiency in the radiation section of the boiler for different particle sizes has been shown with the transient simulation. The simulation aims at providing detailed information of dust behaviour in the waste-heat boiler in sulphide smelting. (author) 11 refs.

  11. A CFD study on the dust behaviour in a metallurgical waste-heat boiler

    Energy Technology Data Exchange (ETDEWEB)

    Yang Yongxiang; Jokilaakso, A. [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Materials Processing and Powder Metallurgy

    1997-12-31

    A waste-heat boiler forms an essential part for the treatment of high temperature flue-gases in most metallurgical processes. Flue-dust carried by the furnace off-gas has to be captured efficiently in the waste-heat boilers before entering the downstream gas purification equipment. Flue dust may accumulate and foul on the heat transfer surfaces such as tube-walls, narrow conjunctions between the boiler and the furnace uptake, and thus may cause smelter shutdown, and interrupt the production. A commercial CFD package is used as the major tool on modelling the dust flow and settling in the waste-heat boiler of an industrial copper flash smelter. In the presentation, dust settling behaviour is illustrated for a wide range of particle sizes, and dust capture efficiency in the radiation section of the boiler for different particle sizes has been shown with the transient simulation. The simulation aims at providing detailed information of dust behaviour in the waste-heat boiler in sulphide smelting. (author) 11 refs.

  12. Integrating multi-objective optimization with computational fluid dynamics to optimize boiler combustion process of a coal fired power plant

    International Nuclear Information System (INIS)

    Liu, Xingrang; Bansal, R.C.

    2014-01-01

    Highlights: • A coal fired power plant boiler combustion process model based on real data. • We propose multi-objective optimization with CFD to optimize boiler combustion. • The proposed method uses software CORBA C++ and ANSYS Fluent 14.5 with AI. • It optimizes heat flux transfers and maintains temperature to avoid ash melt. - Abstract: The dominant role of electricity generation and environment consideration have placed strong requirements on coal fired power plants, requiring them to improve boiler combustion efficiency and decrease carbon emission. Although neural network based optimization strategies are often applied to improve the coal fired power plant boiler efficiency, they are limited by some combustion related problems such as slagging. Slagging can seriously influence heat transfer rate and decrease the boiler efficiency. In addition, it is difficult to measure slag build-up. The lack of measurement for slagging can restrict conventional neural network based coal fired boiler optimization, because no data can be used to train the neural network. This paper proposes a novel method of integrating non-dominated sorting genetic algorithm (NSGA II) based multi-objective optimization with computational fluid dynamics (CFD) to decrease or even avoid slagging inside a coal fired boiler furnace and improve boiler combustion efficiency. Compared with conventional neural network based boiler optimization methods, the method developed in the work can control and optimize the fields of flue gas properties such as temperature field inside a boiler by adjusting the temperature and velocity of primary and secondary air in coal fired power plant boiler control systems. The temperature in the vicinity of water wall tubes of a boiler can be maintained within the ash melting temperature limit. The incoming ash particles cannot melt and bond to surface of heat transfer equipment of a boiler. So the trend of slagging inside furnace is controlled. Furthermore, the

  13. Biomass boiler still best choice

    International Nuclear Information System (INIS)

    Wallace, Paula

    2014-01-01

    Full text: The City of Mount Gambier upgraded its boiler in September after analysis showed that biomass was still the optimal energy option. The Mount Gambier Aquatic Centre was built by the local city council in the 1980s as an outdoor pool facility for the public. The complex has three pools — an Olympic-sized, toddler and a learner pool — for a total volume of 1.38ML (including balance tanks). The large pool is heated to 27-28°C, the smaller one 30-32°C. From the very beginning, the pool water was heated by a biomass boiler, and via two heat exchangers whose combined capacity is 520 kW. The original biomass boiler ran on fresh sawdust from a local timber mill. After thirty years of dedicated service the original boiler had become unreliable and difficult to operate. Replacement options were investigated and included a straight gas boiler, a combined solar hot water and gas option, and biomass boilers. The boiler only produces heat, not electricity. All options were subjected to a triple bottom line assessment, which included potential capital costs, operating costs, community and environmental benefits and costs. The project was also assessed using a tool developed by Mount Gambier City Council that considers the holistic benefits — the CHAT Tool, which stands for Comprehensive Holistic Assessment Tool. “Basically it is a survey that covers environmental, social, economic and governance factors,” the council's environmental sustainability officer, Aaron Izzard told WME. In relation to environmental considerations, the kinds of questions explored by the CHAT Tool included: Sustainable use of resources — objective is to reduce council's dependence on non-renewable resources; Greenhouse emissions — objective is to reduce council's contribution of GHG into the atmosphere; Air quality — objective is to improve local air quality. The conclusion of these analyses was that while a biomass boiler would have a higher capital cost than a straight gas

  14. Installations of SNCR on bark-fired boilers; Uppfoeljning av SNCR-installationer paa barkpannor

    Energy Technology Data Exchange (ETDEWEB)

    Hjalmarsson, A.K.; Hedin, K. [AaF-Energikonsult, Stockholm (Sweden); Andersson, Lars [AaF-IPK (Sweden)

    1997-01-01

    Experience has been collected from the twelve bark-fired boilers in Sweden with selective non catalytic reduction (SNCR) installations to reduce emissions of nitrogen oxides. Most of the boilers have slope grates, but there are also two boilers with cyclone ovens and two fluidized bed boilers. In addition to oil there are also possibilities to burn other fuel types in most boilers, such as sludge from different parts of the pulp and paper mills, saw dust and wood chips. The SNCR installations seems in general to be of simple design. In most installations the injection nozzles are located in existing holes in the boiler walls. The availability is reported to be good from several of the SNCR installations. There has been tube leakage in several boilers. The urea system has resulted in corrosion and in clogging of one oil burner. This incident has resulted in a decision not to use SNCR system with the present design of the system. The fuel has also caused operational problems with the SNCR system in several of the installations due to variations in the moisture content and often high moisture content in bark and sludge, causing temperature variations. The availability is presented to be high for the SNCR system at several of the plants, in two of them about 90 %. The results in NO{sub x} reduction vary between the installations depending on boiler, fuel and operation. The emissions are between 45 and 100 mg NO{sub 2}/MJ fuel input and the NO{sub x} reduction rates are in most installations between 30 and 40 %, the lowest 20 and the highest 70 %. 13 figs, 3 tabs

  15. A numerical study on thermal behavior of a D-type water-cooled steam boiler

    International Nuclear Information System (INIS)

    Moghari, M.; Hosseini, S.; Shokouhmand, H.; Sharifi, H.; Izadpanah, S.

    2012-01-01

    To achieve a precise assessment on thermal performance of a D-type water-cooled natural gas-fired boiler the present paper was aimed at determining temperature distribution of water and flue gas flows in its different heat exchange equipment. Using the zonal method to predict thermal radiation treatment in the boiler furnace and a numerical iterative approach, in which heat and fluid flow relations associated with different heat surfaces in the boiler convective zone were employed to estimate heat transfer characteristics, enabled this numerical study to obtain results in good agreement with experimental data measured in the utility site during steady state operation. A constant flow rate for a natural gas fuel of specified chemical composition was assumed to be mixed with a given excess ratio of air flow at a full boiler load. Significant results attributed to distribution of heat flux on different furnace walls and that of flue gas and water/steam temperature in different convective stages including superheater, evaporating risers and downcomers modules, and economizer were obtained. Besides the rate of heat absorption in every stage and other essential parameters in the boiler design too, inherent thermal characteristics like radiative and convective heat transfer coefficients as well as overall heat transfer conductance and effectiveness of convective stages considered as cross-flow heat exchangers were eventually presented for the given operating condition. - Highlights: ► Detailed distribution of heat flux on all of the boiler furnace walls was obtained. ► Flue gas and water thermal behaviors in different heating sections were evaluated. ► A good agreement was made between numerical results and experimental data. ► Contribution of the boiler furnace to the total thermal absorption was 39%. ► Contribution of the boiler tube banks to the total thermal absorption was 61%.

  16. Probabilistic approach to determining the optimum replacement of a superheater stage in 680 MW coal-fired boiler

    Energy Technology Data Exchange (ETDEWEB)

    Bos, Robert; Star, Ruud van der [Nuon Power Generation, Amsterdam (Netherlands)

    2009-07-01

    The boiler of the NUON power plant HW08 that went into operation in 1993 is designed as Benson boiler and mainly fired with hard coal. A creep-related tube failure occurred in the tertiary superheater that had been due to increased wall temperature caused by steam side formation of oxide layers. The theoretical lifetime of the components was calculated with the aid of the results of steam side oxide measurements and condition evaluation of the tertiary superheater with the aid of tube samples. The objective is to establish an operation and maintenance schedule for the desired operating lifetime of 300,000 hours. (orig.)

  17. 46 CFR 52.25-20 - Exhaust gas boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Exhaust gas boilers. 52.25-20 Section 52.25-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING POWER BOILERS Other Boiler Types § 52.25-20 Exhaust gas boilers. Exhaust gas boilers with a maximum allowable working pressure...

  18. 46 CFR 63.25-1 - Small automatic auxiliary boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Small automatic auxiliary boilers. 63.25-1 Section 63.25... AUXILIARY BOILERS Requirements for Specific Types of Automatic Auxiliary Boilers § 63.25-1 Small automatic auxiliary boilers. Small automatic auxiliary boilers defined as having heat-input ratings of 400,000 Btu/hr...

  19. Fluidized bed boiler feed system

    Science.gov (United States)

    Jones, Brian C.

    1981-01-01

    A fluidized bed boiler feed system for the combustion of pulverized coal. Coal is first screened to separate large from small particles. Large particles of coal are fed directly to the top of the fluidized bed while fine particles are first mixed with recycled char, preheated, and then fed into the interior of the fluidized bed to promote char burnout and to avoid elutriation and carryover.

  20. Inception report and gap analysis. Boiler inspection

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-06-01

    This inception and gap analysis report on boilers in Latvia, has been prepared in the framework of the 'Implementation of the EU directive on energy performance of buildings: development of the Latvian Scheme for energy auditing of building and inspection of boilers'. The report is the basis for the establishment of training of boiler inspectors; it develops a gap analysis for better understanding and estimating the number of installations in Latvia and develops suggestions for the institutional set up. In particular includes information on existing standard and regulation on boiler, suggestion for the content of the training material of experts for boiler inspections and a syllabus of the training course. A specific section is dedicated to the suggestion for certification system of trained boiler inspectors. (au)

  1. Inception report and gap analysis. Boiler inspection

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-06-01

    This inception and gap analysis report on boilers in Latvia, has been prepared in the framework of the 'Implementation of the EU directive on energy performance of buildings: development of the Latvian Scheme for energy auditing of building and inspection of boilers'. The report is the basis for the establishment of training of boiler inspectors; it develops a gap analysis for better understanding and estimating the number of installations in Latvia and develops suggestions for the institutional set up. In particular includes information on existing standard and regulation on boiler, suggestion for the content of the training material of experts for boiler inspections and a syllabus of the training course. A specific section is dedicated to the suggestion for certification system of trained boiler inspectors. (au)

  2. Further development of recovery boiler; Soodakattilan kehitystyoe

    Energy Technology Data Exchange (ETDEWEB)

    Janka, K.; Siiskonen, P.; Sundstroem, K. [Tampella Power Oy, Tampere (Finland)] [and others

    1996-12-01

    The global model of a recovery boiler was further developed. The aim is to be able to model the velocity, temperature and concentration fields in a boiler. At this moment the model includes submodels for: droplet drying, pyrolysis, char burning, gas burning and for droplet trajectory. The preliminary study of NO{sub x} and fly ash behaviour in a boiler was carried out. The study concerning flow field in the superheater area was carried out a 2-dimensional case in which the inflow parameters were taken from global model of a recovery boiler. Further the prediction methods of fouling in a recovery boiler were developed based on theoretical calculations of smelting behaviour of multicomponent mixtures and measurements at operating recovery boilers. (author)

  3. Application of an empirical model in CFD simulations to predict the local high temperature corrosion potential in biomass fired boilers

    International Nuclear Information System (INIS)

    Gruber, Thomas; Scharler, Robert; Obernberger, Ingwald

    2015-01-01

    To gain reliable data for the development of an empirical model for the prediction of the local high temperature corrosion potential in biomass fired boilers, online corrosion probe measurements have been carried out. The measurements have been performed in a specially designed fixed bed/drop tube reactor in order to simulate a superheater boiler tube under well-controlled conditions. The investigated boiler steel 13CrMo4-5 is commonly used as steel for superheater tube bundles in biomass fired boilers. Within the test runs the flue gas temperature at the corrosion probe has been varied between 625 °C and 880 °C, while the steel temperature has been varied between 450 °C and 550 °C to simulate typical current and future live steam temperatures of biomass fired steam boilers. To investigate the dependence on the flue gas velocity, variations from 2 m·s −1 to 8 m·s −1 have been considered. The empirical model developed fits the measured data sufficiently well. Therefore, the model has been applied within a Computational Fluid Dynamics (CFD) simulation of flue gas flow and heat transfer to estimate the local corrosion potential of a wood chips fired 38 MW steam boiler. Additionally to the actual state analysis two further simulations have been carried out to investigate the influence of enhanced steam temperatures and a change of the flow direction of the final superheater tube bundle from parallel to counter-flow on the local corrosion potential. - Highlights: • Online corrosion probe measurements in a fixed bed/drop tube reactor. • Development of an empirical corrosion model. • Application of the model in a CFD simulation of flow and heat transfer. • Variation of boundary conditions and their effects on the corrosion potential

  4. Boiler plants completed in record time

    International Nuclear Information System (INIS)

    Anon.

    2001-01-01

    Bubbling fluidised bed (BFB) combustion has steadily increased its share of the boiler market in recent years, particularly in the Nordic region, where it is particularly well-suited to handling the high moisture content biofuels produced and used by the forest products industry. Foster Wheeler is the world's leading supplier of fluidised bed combustion technology. Over 200 of the more than 300 fluidised bed boilers supplied by the company are circulating fluidised bed (CFB) designs, a market in which Foster Wheeler has more than a 40% share. Foster Wheeler Energia Oy supplied the Myllykoski project at Anjalankoski with a fluidised bed boiler, auxiliary steam boilers, and flue gas scrubber systems

  5. The Technology Introduction of Chain Boiler Energy Conservation Transformation

    Science.gov (United States)

    Li, Henan; Liu, Xiwen; Yuan, Hong; Lin, Jiadai; Zhang, Yu

    2017-12-01

    Introduced the present status of chain boiler efficiency is low, the system analysis of the chain boiler optimization and upgrading of technology, for the whole progress of chain boiler to provide some ideas and reference.

  6. Nature of fireside deposits in a bagasse and groundnut shell fired 20 MW thermal boiler

    International Nuclear Information System (INIS)

    Srikanth, S.; Das, S.K.; Ravikumar, B.; Rao, D.S.; Nandakumar, K.; Vijayan, P.

    2004-01-01

    The nature of deposit formation on the fireside surfaces of the boiler tubes in the various parts (water walls, platen superheater, final superheater, economizer, electrostatic precipitator etc.) of a commercial 20 MW stoker-fired boiler being fired with a mixture of 80% bagasse and 20% groundnut shell has been analyzed. The deposits in the various portions of the boiler were characterized by particle size analysis, chemical analysis, X-ray diffraction and scanning electron microscopy. The deposits were found to be mainly quartz, alkali and alkaline earth silicates and sulfates. From the phase constitution and other microscopic characteristics of the deposit, it can be inferred that the silicates in the deposit formed through inertial impaction and the sulfates formed by vapor phase deposition

  7. Nature of fireside deposits in a bagasse and groundnut shell fired 20 MW thermal boiler

    Energy Technology Data Exchange (ETDEWEB)

    Srikanth, S.; Rao, D.S. [National Metallurgical Laboratory Madras Centre, Chennai (India); Swapan, S.K.; Das, K.; Ravikumar, B. [National Metallurgical Laboratory, Jamshedpur (India). Materials Characterization Division; Nandakumar, K.; Vijayan, P. [Bharat Heavy Electricals Limited, Tiruchirappalli (India). Research and Development Section

    2004-10-01

    The nature of deposit formation on the fireside surfaces of the boiler tubes in the various parts (water walls, platen superheater, final superheater, economizer, electrostatic precipitator etc.) of a commercial 20 MW stoker-fired boiler being fired with a mixture of 80% bagasse and 20% groundnut shell has been analyzed. The deposits in the various portions of the boiler were characterized by particle size analysis, chemical analysis, X-ray diffraction and scanning electron microscopy. The deposits were found to be mainly quartz, alkali and alkaline earth silicates and sulfates. From the phase constitution and other microscopic characteristics of the deposit, it can be inferred that the silicates in the deposit formed through inertial impaction and the sulfates formed by vapor phase deposition. (author)

  8. CFD analysis of temperature imbalance in superheater/reheater region of tangentially coal-fired boiler

    Science.gov (United States)

    Zainudin, A. F.; Hasini, H.; Fadhil, S. S. A.

    2017-10-01

    This paper presents a CFD analysis of the flow, velocity and temperature distribution in a 700 MW tangentially coal-fired boiler operating in Malaysia. The main objective of the analysis is to gain insights on the occurrences in the boiler so as to understand the inherent steam temperature imbalance problem. The results show that the root cause of the problem comes from the residual swirl in the horizontal pass. The deflection of the residual swirl due to the sudden reduction and expansion of the flow cross-sectional area causes velocity deviation between the left and right side of the boiler. This consequently results in flue gas temperature imbalance which has often caused tube leaks in the superheater/reheater region. Therefore, eliminating the residual swirl or restraining it from being diverted might help to alleviate the problem.

  9. Characterization and Quantification of Deposits Buildup and Removal in Biomass Suspension-Fired Boilers

    DEFF Research Database (Denmark)

    Shafique Bashir, Muhammad; Jensen, Peter Arendt; Frandsen, Flemming

    2010-01-01

    Utilization of biomass as wood or straw in large suspension­fired boilers is an efficient method to reduce the use of fossil fuels consumption and to reduce the net CO2 formation. However, the presence of chlorine and alkali metals in biomass (straw) generate ash with a low melting point and induce...... large problems of ash deposit formation on the superheater tubes. Full scale studies on biomass ash deposition and removal had been done on biomass grate boilers, while only limited data is available from biomass suspension­firing. The aim of this study was to investigate deposit mass uptake, heat...... uptake reduction, fly ash and deposit characteristics, and deposit removal by using an advanced online deposit probe in a suspension­fired boiler using wood and straw pellets as fuel. The influence of fuel type and probe exposure time on the ash deposition rate, the heat uptake, the fly ash and deposit...

  10. Advanced technique for computing fuel combustion properties in pulverized-fuel fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Kotler, V.R. (Vsesoyuznyi Teplotekhnicheskii Institut (Russian Federation))

    1992-03-01

    Reviews foreign technical reports on advanced techniques for computing fuel combustion properties in pulverized-fuel fired boilers and analyzes a technique developed by Combustion Engineering, Inc. (USA). Characteristics of 25 fuel types, including 19 grades of coal, are listed along with a diagram of an installation with a drop tube furnace. Characteristics include burn-out intensity curves obtained using thermogravimetric analysis for high-volatile bituminous, semi-bituminous and coking coal. The patented LFP-SKM mathematical model is used to model combustion of a particular fuel under given conditions. The model allows for fuel particle size, air surplus, load, flame height, and portion of air supplied as tertiary blast. Good agreement between computational and experimental data was observed. The method is employed in designing new boilers as well as converting operating boilers to alternative types of fuel. 3 refs.

  11. Deposit Shedding in Biomass-Fired Boilers: Shear Adhesion Strength Measurements

    DEFF Research Database (Denmark)

    Laxminarayan, Yashasvi; Jensen, Peter Arendt; Wu, Hao

    2017-01-01

    Ash deposition on boiler surfaces is a major problem encountered in biomass combustion. Timely removal of ash deposits is essentialfor optimal boiler operation. In order to improve the understanding of deposit shedding in boilers, this study investigates the adhesion strength of biomass ash from...... off by an electrically controlled arm, and the corresponding adhesion strength was measured. The effect of sintering temperature, sintering time, deposit composition, thermal shocks on the deposit, and steel type was investigated. The results reveal that the adhesion strength of ash deposits...... is dependent on two factors: ash melt fraction, and corrosion occurring at the deposit–tube interface. Adhesion strength increases with increasing sintering temperature, sharply increasing at the ash deformation temperature. However, sintering time, as well as the type of steel used, does not have...

  12. High Temperature Corrosion Problem of Boiler Components in presence of Sulfur and Alkali based Fuels

    Science.gov (United States)

    Ghosh, Debashis; Mitra, Swapan Kumar

    2011-04-01

    Material degradation and ageing is of particular concern for fossil fuel fired power plant components. New techniques/approaches have been explored in recent years for Residual Life assessment of aged components and material degradation due to different damage mechanism like creep, fatigue, corrosion and erosion etc. Apart from the creep, the high temperature corrosion problem in a fossil fuel fired boiler is a matter of great concern if the fuel contains sulfur, chlorine sodium, potassium and vanadium etc. This paper discusses the material degradation due to high temperature corrosion in different critical components of boiler like water wall, superheater and reheater tubes and also remedial measures to avoid the premature failure. This paper also high lights the Residual Life Assessment (RLA) methodology of the components based on high temperature fireside corrosion. of different critical components of boiler.

  13. A two-parameter preliminary optimization study for a fluidized-bed boiler through a comprehensive mathematical simulator

    Energy Technology Data Exchange (ETDEWEB)

    Rabi, Jose A.; Souza-Santos, Marcio L. de [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Energia]. E-mails: jrabi@fem.unicamp.br; dss@fem.unicamp.br

    2000-07-01

    Modeling and simulation of fluidized-bed equipment have demonstrated their importance as a tool for design and optimization of industrial equipment. Accordingly, this work carries on an optimization study of a fluidized-bed boiler with the aid of a comprehensive mathematical simulator. The configuration data of the boiler are based on a particular Babcock and Wilcox Co. (USA) test unit. Due to their importance, the number of tubes in the bed section and the air excess are chosen as the parameters upon which the optimization study is based. On their turn, the fixed-carbon conversion factor and the boiler efficiency are chosen as two distinct optimization objectives. The results from both preliminary searches are compared. The present work is intended to be just a study on possible routes for future optimization of larger boilers. Nonetheless, the present discussion might give some insight on the equipment behavior. (author)

  14. Tube plug

    International Nuclear Information System (INIS)

    Zafred, P. R.

    1985-01-01

    The tube plug comprises a one piece mechanical plug having one open end and one closed end which is capable of being inserted in a heat exchange tube and internally expanded into contact with the inside surface of the heat exchange tube for preventing flow of a coolant through the heat exchange tube. The tube plug also comprises a groove extending around the outside circumference thereof which has an elastomeric material disposed in the groove for enhancing the seal between the tube plug and the tube

  15. Final Report, Materials for Industrial Heat Recovery Systems, Tasks 3 and 4 Materials for Heat Recovery in Recovery Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Keiser, James R.; Kish, Joseph R.; Singh, Preet M.; Sarma, Gorti B.; Yuan, Jerry; Gorog, J. Peter; Frederick, Laurie A.; Jette, Francois R.; Meisner, Roberta A.; Singbeil, Douglas L.

    2007-12-31

    The DOE-funded project on materials for industrial heat recovery systems included four research tasks: materials for aluminum melting furnace recuperator tubes, materials and operational changes to prevent cracking and corrosion of the co-extruded tubes that form primary air ports in black liquor recovery boilers, the cause of and means to prevent corrosion of carbon steel tubes in the mid-furnace area of recovery boilers, and materials and operational changes to prevent corrosion and cracking of recovery boiler superheater tubes. Results from studies on the latter two topics are given in this report while separate reports on results for the first two tasks have already been published. Accelerated, localized corrosion has been observed in the mid-furnace area of kraft recovery boilers. This corrosion of the carbon steel waterwall tubes is typically observed in the vicinity of the upper level of air ports where the stainless clad co-extruded wall tubes used in the lower portion of the boiler are welded to the carbon steel tubes that extend from this transition point or “cut line” to the top of the boiler. Corrosion patterns generally vary from one boiler to another depending on boiler design and operating parameters, but the corrosion is almost always found within a few meters of the cut line and often much closer than that. This localized corrosion results in tube wall thinning that can reach the level where the integrity of the tube is at risk. Collection and analysis of gas samples from various areas near the waterwall surface showed reducing and sulfidizing gases were present in the areas where corrosion was accelerated. However, collection of samples from the same areas at intervals over a two year period showed the gaseous environment in the mid-furnace section can cycle between oxidizing and reducing conditions. These fluctuations are thought to be due to gas flow instabilities and they result in an unstable or a less protective scale on the carbon steel

  16. Improved Materials for Use as Components in Kraft Black Liquor Recovery Boilers; TOPICAL

    International Nuclear Information System (INIS)

    Keiser, J.R.

    2001-01-01

    This Cooperative Research and Development Agreement (CRADA) was undertaken to evaluate current and improved materials and materials processing conditions for use as components in kraft black liquor recovery boilers and other unit processes. The main areas addressed were: (1) Improved Black Liquor Nozzles, (2) Weld Overlay of Composite Floor Tubes, and (3) Materials for Lime Kilns. Iron aluminide was evaluated as an alternate material for the nozzles used to inject an aqueous solution known as black liquor into recovery boilers as well for the uncooled lining in the ports used for the nozzles. Although iron aluminide is known to have much better sulfidation resistance in gases than low alloy and stainless steels, it did not perform adequately in the environment where it came into contact with molten carbonate, sulfide and sulfate salts. Weld overlaying carbon steel tubes with a layer of stainless weld metal was a proposed method of extending the life of recovery boiler floor tubes that have experienced considerable fireside corrosion. After exposure under service conditions, sections of weld overlaid floor tubes were removed from a boiler floor and examined metallographically. Examination results indicated satisfactory performance of the tubes. Refractory-lined lime kilns are a critical component of the recovery process in kraft pulp mills, and the integrity of the lining is essential to the successful operation of the kiln. A modeling study was performed to determine the cause of, and possible solutions for, the repeated loss of the refractory lining from the cooled end of a particular kiln. The evaluation showed that the temperature, the brick shape and the coefficient of friction between the bricks were the most important parameters influencing the behavior of the refractory lining

  17. Particulate emission factor: A case study of a palm oil mill boiler

    International Nuclear Information System (INIS)

    Chong, W.C.; Rashid, M.; Ramli, M.; Zainura, Z.N.; NorRuwaida, J.

    2010-01-01

    A study to investigate the particulate emission from a boiler of a palm oil mill plant equipped with a multi-cyclones particulate arrest or was performed and reported in this paper. The particulate emission concentration was measured at the outlet of a 8 mt/ hr capacity water-tube typed boiler of a palm oil mill plant processing 27mt/ hr of fresh fruit bunch (FFB). The particulate sample was collected iso-kinetically using the USEPA method 5 sampling train through a sampling port made at the duct of the exiting flue gas between the boiler and a multi-cyclones unit. Results showed that the particulate emission rates exiting the boiler varied from 0.09 to 0.60 g/s with an average of 0.29 + 0.18 g/ s. While the average particulate emission concentration exiting the boiler was 12.1 + 7.36 g/ Nm 3 (corrected to 7 % oxygen concentration), ranging from 3.62 to 25.3 g/ Nm 3 (at 7 % O 2 ) of the flue gas during the measurement. Based on the 27 mt/ hr FFB processed and the capacity of the boiler of 8mt steam/ hr, the calculated particulate emission factor was 39 g particulate/ mt FFB processed or 131 g particulate/ mt boiler capacity, respectively. In addition, based on the finding and in order to comply with the emission limits of 0.4 g/ Nm 3 , the collection efficiency of any given particulate emission pollution control system to consider for the mill will be from 87 to 98 %, which is not easily achievable with the existing multi-cyclones unit. A considerable amount of efforts are still needed pertaining to the particulate emission control problem in the industry. (author)

  18. MODELLING, SIMULATING AND OPTIMIZING BOILERS

    DEFF Research Database (Denmark)

    Sørensen, K.; Condra, T.; Houbak, Niels

    2003-01-01

    , and the total stress level (i.e. stresses introduced due to internal pressure plus stresses introduced due to temperature gradients) must always be kept below the allowable stress level. In this way, the increased water-/steam space that should allow for better dynamic performance, in the end causes limited...... freedom with respect to dynamic operation of the plant. By means of an objective function including as well the price of the plant as a quantification of the value of dynamic operation of the plant an optimization is carried out. The dynamic model of the boiler plant is applied to define parts...

  19. Wood fuelled boiler operating costs

    International Nuclear Information System (INIS)

    Sandars, D.L.

    1995-01-01

    This report is a management study into the operating costs of wood-fired boilers. Data obtained from existing wood-fired plant has been analysed and interpreted using the principles of machinery management and the science that underlies the key differences between this fuel and any other. A set of budgeting principles has been developed for the key areas of labour requirement, insurance, maintenance and repair and electricity consumption. Other lesser cost centres such as the provision of shelter and the effects of neglect and accidents have also been considered, and a model constructed. (author)

  20. High Temperature Behavior of Cr3C2-NiCr Coatings in the Actual Coal-Fired Boiler Environment

    Science.gov (United States)

    Bhatia, Rakesh; Sidhu, Hazoor Singh; Sidhu, Buta Singh

    2015-03-01

    Erosion-corrosion is a serious problem observed in steam-powered electricity generation plants, and industrial waste incinerators. In the present study, four compositions of Cr3C2-(Ni-20Cr) alloy coating powder were deposited by high-velocity oxy-fuel spray technique on T-91 boiler tube steel. The cyclic studies were performed in a coal-fired boiler at 1123 K ± 10 K (850 °C ± 10 °C). X-ray diffraction, scanning electron microscopy/energy dispersive X-ray analysis and elemental mapping analysis techniques were used to analyze the corrosion products. All the coatings deposited on T-91 boiler tube steel imparted hot corrosion resistance. The 65 pctCr3C2 -35 pct (Ni-20Cr)-coated T-91 steel sample performed better than all other coated samples in the given environment.

  1. Gastrostomy Tube (G-Tube)

    Science.gov (United States)

    ... any of these problems: a dislodged tube a blocked or clogged tube any signs of infection (including redness, swelling, or warmth at the tube site; discharge that's yellow, green, or foul-smelling; fever) excessive bleeding or drainage from the tube site severe abdominal pain lasting ...

  2. Study of the possibility of thermal utilization of contaminated water in low-power boilers

    Science.gov (United States)

    Roslyakov, P. V.; Proskurin, Y. V.; Zaichenko, M. N.

    2017-09-01

    The utilization of water contaminated with oil products is a topical problem for thermal power plants and boiler houses. It is reasonable to use special water treatment equipment only for large power engineering and industry facilities. Thermal utilization of contaminated water in boiler furnaces is proposed as an alternative version of its utilization. Since there are hot-water fire-tube boilers at many enterprises, it is necessary to study the possibility of thermal utilization of water contaminated with oil products in their furnaces. The object of this study is a KV-GM-2.0 boiler with a heating power of 2 MW. The pressurized burner developed at the Moscow Power Engineering Institute, National Research University, was used as a burner device for supplying liquid fuel. The computational investigations were performed on the basis of the computer simulation of processes of liquid fuel atomization, mixing, ignition, and burnout; in addition, the formation of nitrogen oxides was simulated on the basis of ANSYS Fluent computational dynamics software packages, taking into account radiative and convective heat transfer. Analysis of the results of numerical experiments on the combined supply of crude oil and water contaminated with oil products has shown that the thermal utilization of contaminated water in fire-tube boilers cannot be recommended. The main causes here are the impingement of oil droplets on the walls of the flame tube, as well as the delay in combustion and increased emissions of nitrogen oxides. The thermal utilization of contaminated water combined with diesel fuel can be arranged provided that the water consumption is not more than 3%; however, this increases the emission of nitrogen oxides. The further increase in contaminated water consumption will lead to the reduction of the reliability of the combustion process.

  3. Slagging and fouling evaluation of PC-fired boilers using AshPro{sup SM}

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhanhua; Iman, Felicia; Lu, Pisi [SmartBurn, LLC, Madison, WI (United States)

    2013-07-01

    SmartBurn {sup registered} applied AshPro{sup SM} model to two 512 MW Tangential-fired (T-fired) boilers firing US western sub- bituminous coals to evaluate the boiler slagging behaviors with different operating conditions and OFA. The boiler convective pass fouling behaviors with three different coals were also evaluated. The slagging evaluation results indicate that the OFA configuration and air flow distribution have dramatically impacts on the ash impaction rates and slagging patterns on the furnace walls. Deposit growth and strength vary at the different regions of the furnace walls. The fouling evaluation reveals that the tube bank configuration, the amount of incoming ash, the profiles of flue gas temperature, velocity, and species all have significant impacts on fouling deposit formation, growth, and strength development. In addition, the varying ash particle sizes and chemical compositions from different coals also play important roles on the fouling deposit strength development and removal. The investigation demonstrated that AshPro{sup SM} model can be used to evaluate localized slagging and fouling problems that are related to specific boiler configuration and operating conditions. It can be used to identify the major causes of ash deposition and can guide changes in boiler operation.

  4. Economic evaluation of a coal fired boiler

    International Nuclear Information System (INIS)

    Briem, J.J.

    1983-01-01

    This paper provides basic information on boiler economics which will assist steam users in analyzing the feasibility of using coal to generate steam - in either new or existing facilities. The information presented covers boilers ranging in size from 10,000 to 100,000 pounds per hour steaming capacity

  5. 46 CFR 109.555 - Propulsion boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Propulsion boilers. 109.555 Section 109.555 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS OPERATIONS Miscellaneous § 109.555 Propulsion boilers. The master or person in charge and the engineer in charge shall...

  6. 29 CFR 1915.162 - Ship's boilers.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Ship's boilers. 1915.162 Section 1915.162 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Ship's Machinery and Piping Systems § 1915.162 Ship's boilers. (a) Before...

  7. Application of the Critical Heat Flux Look-Up Table to Large Diameter Tubes

    Directory of Open Access Journals (Sweden)

    M. El Nakla

    2013-01-01

    Full Text Available The critical heat flux look-up table was applied to a large diameter tube, namely 67 mm inside diameter tube, to predict the occurrence of the phenomenon for both vertical and horizontal uniformly heated tubes. Water was considered as coolant. For the vertical tube, a diameter correction factor was directly applied to the 1995 critical heat flux look-up table. To predict the occurrence of critical heat flux in horizontal tube, an extra correction factor to account for flow stratification was applied. Both derived tables were used to predict the effect of high heat flux and tube blockage on critical heat flux occurrence in boiler tubes. Moreover, the horizontal tube look-up table was used to predict the safety limits of the operation of boiler for 50% allowable heat flux.

  8. Developing Boiler Concepts as Integrated Units

    DEFF Research Database (Denmark)

    Sørensen, Kim; Condra, Thomas Joseph; Houbak, Niels

    2004-01-01

    - consisting of pressure part, burner and control system. The Technical University of Denmark, MEK - Energy Engineering Section [12] has participated in the modelling process. The project has included static and dynamic modelling of the boiler concept. For optimization of operation, verication of performance......With the objective to be able to optimize the design and operation of steam boiler concepts Aalborg Industries A/S [1] has together with Aalborg University, Institute of Energy Technology [9] carried out a development project paying special attention to the boiler concept as an integrated unit......, emissions and to obtain long time operation experiences with the boiler concept, a full scale prototype has been built and these tests have been accomplished on the prototype. By applying this integrated unit approach to the boiler concept development it has been possible to optimize the different building...

  9. Investigations on the Behavior of HVOF and Cold Sprayed Ni-20Cr Coating on T22 Boiler Steel in Actual Boiler Environment

    Science.gov (United States)

    Bala, Niraj; Singh, Harpreet; Prakash, Satya; Karthikeyan, J.

    2012-01-01

    High temperature corrosion accompanied by erosion is a severe problem, which may result in premature failure of the boiler tubes. One countermeasure to overcome this problem is the use of thermal spray protective coatings. In the current investigation high velocity oxy-fuel (HVOF) and cold spray processes have been used to deposit commercial Ni-20Cr powder on T22 boiler steel. To evaluate the performance of the coatings in actual conditions the bare as well as the coated steels were subjected to cyclic exposures, in the superheater zone of a coal fired boiler for 15 cycles. The weight change and thickness loss data were used to establish kinetics of the erosion-corrosion. X-ray diffraction, surface and cross-sectional field emission scanning electron microscope/energy dispersive spectroscopy (FE-SEM/EDS) and x-ray mapping techniques were used to analyse the as-sprayed and corroded specimens. The HVOF sprayed coating performed better than its cold sprayed counterpart in actual boiler environment.

  10. 78 FR 286 - Circular Welded Carbon Steel Pipes and Tubes From Turkey; Amended Final Results of Antidumping...

    Science.gov (United States)

    2013-01-03

    ... the scope of this order, except for line pipe, oil country tubular goods, boiler tubing, cold-drawn or... order (``APO'') of their responsibility concerning the disposition of proprietary information disclosed...

  11. Research on the Superheater Material Properties for USC Boiler with 700°C Steam Parameter

    Science.gov (United States)

    Chongbin, Wang; Xueyuan, Xu; Yufeng, Zhu; Yongqiang, Jin; Hui, Tong; Yu, Wang; Xiaoli, Lu

    This paper discusses the materials' properties of superheater for 700°C USC boiler, including Sanicro25, HR6W, 617mod and 740H, and analyzes the range of applicable temperature of superheater made of different tubes, such as T91, T92, Super304H, TP310HCbN, Sanicro25, HR6W, 617Mod and 740H. In addition, some suggestions on the material selection have been proposed.

  12. 46 CFR 61.05-15 - Boiler mountings and attachments.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Boiler mountings and attachments. 61.05-15 Section 61.05... TESTS AND INSPECTIONS Tests and Inspections of Boilers § 61.05-15 Boiler mountings and attachments. (a....05-10. (b) Each stud or bolt for each boiler mounting that paragraph (c) of this section requires to...

  13. 46 CFR 63.25-7 - Exhaust gas boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Exhaust gas boilers. 63.25-7 Section 63.25-7 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS Requirements for Specific Types of Automatic Auxiliary Boilers § 63.25-7 Exhaust gas boilers. (a) Construction...

  14. 49 CFR 230.30 - Lap-joint seam boilers.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Lap-joint seam boilers. 230.30 Section 230.30..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Inspection and Repair § 230.30 Lap-joint seam boilers. Every boiler having lap-joint longitudinal seams...

  15. NOx Control Options and Integration for US Coal Fired Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Mike Bockelie; Kevin Davis; Temi Linjewile; Connie Senior; Eric Eddings; Kevin Whitty; Larry Baxter; Calvin Bartholomew; William Hecker; Stan Harding; Robert Hurt

    2003-12-31

    This is the fourteenth Quarterly Technical Report for DOE Cooperative Agreement No: DEFC26-00NT40753. The goal of the project is to develop cost effective analysis tools and techniques for demonstrating and evaluating low NOx control strategies and their possible impact on boiler performance for boilers firing US coals. The Electric Power Research Institute (EPRI) is providing co-funding for this program. Using the initial CFD baseline modeling of the Gavin Station and the plant corrosion maps, six boiler locations for the corrosion probes were identified and access ports have been installed. Preliminary corrosion data obtained appear consistent and believable. In situ, spectroscopic experiments at BYU reported in part last quarter were completed. New reactor tubes have been made for BYU's CCR that allow for testing smaller amounts of catalyst and thus increasing space velocity; monolith catalysts have been cut and a small reactor that can accommodate these pieces for testing is in its final stages of construction. A poisoning study on Ca-poisoned catalysts was begun this quarter. A possible site for a biomass co-firing test of the slipstream reactor was visited this quarter. The slipstream reactor at Rockport required repair and refurbishment, and will be re-started in the next quarter. This report describes the final results of an experimental project at Brown University on the fundamentals of ammonia / fly ash interactions with relevance to the operation of advanced NOx control technologies such as selective catalytic reduction. The Brown task focused on the measurement of ammonia adsorption isotherms on commercial fly ash samples subjected to a variety of treatments and on the chemistry of dry and semi-dry ammonia removal processes.

  16. Dynamic model of a natural water circulation boiler suitable for on-line monitoring of fossil/alternative fuel plants

    International Nuclear Information System (INIS)

    Sedić, Almir; Katulić, Stjepko; Pavković, Danijel

    2014-01-01

    Highlights: • Derivation of dynamic model of a natural water circulation boiler is presented. • Model is derived by employing basic laws of conservation of mass, energy and momentum. • Thus obtained boiler model does not include empirical relationships. • Model is validated against experimental data related to an external disturbance event. • The final model is used for simulation analysis/assessment of key boiler quantities. - Abstract: The environmental protection policies and legal obligations motivate process industries to implement new low-emission and high-efficiency technologies. For the purpose of production process optimization and related control system design it is worthwhile to first build an appropriate process model. Apart from favorable execution speed, accuracy, and reliability features, the model also needs to be straightforward and only include the physical and design characteristics of the overall plant and its individual components, instead of relying on empirical relationships. To this end, this paper presents a nonlinear dynamic model of the single-drum natural-circulation steam boiler evaporator circuit, based exclusively on the fundamental physical laws of conservation of mass, energy and momentum, wherein the reliance upon empirical relationships has been entirely avoided. The presented boiler system modeling approach is based on the analysis of the physical phenomena within the boiler drum, as well as within downcomer and furnace tubes, and it also takes into account the boiler system design-specific features such as cyclone steam separators, thus facilitating the derivation of a fully-physical process model. Due to the straightforwardness of the derived process model, it should also be useful for the analysis of similar steam boiler facilities, requiring only adjustments of key operational and design parameters such as operating pressure, temperature, steam capacity and characteristics of ancillary equipment such as pumps. To

  17. Electrical design requirements for electrode boilers for nuclear plants

    International Nuclear Information System (INIS)

    Kempker, M.J.

    1979-01-01

    Medium-voltage steam electrode boilers, in the 20- to 50-MW range, have become an attractive alternative to comparable fossil-fueled boilers as a source of auxiliary steam during the startup and normal shutdown of nuclear power plants. The electrode boiler represents a favorable option because of environmental, fire protection, and licensing considerations. However, this electrical option brings some difficult design problems for which solutions are required in order to integrate the electrode boiler into the plant low resistance grounded power system. These considerations include the effects of an unbalanced electrode boiler on the performance of polyphase induction motors, boiler grounding for personnel safety, boiler neutral grounding, and ground relaying

  18. Environmental performance assessment of utility boiler energy conversion systems

    International Nuclear Information System (INIS)

    Li, Changchun; Gillum, Craig; Toupin, Kevin; Park, Young Ho; Donaldson, Burl

    2016-01-01

    Highlights: • Sustainability analyses of utility boilers are performed. • Natural gas fired boilers have the least CO_2 emissions in fossil fueled boilers. • Solar boilers rank last with an emergy yield ratio of 1.2. • Biomass boilers have the best emergy sustainability index. - Abstract: A significant amount of global electric power generation is produced from the combustion of fossil fuels. Steam boilers are one of the most important components for steam and electricity production. The objective of this paper is to establish a theoretical framework for the sustainability analysis of a utility boiler. These analyses can be used by decision-makers to diagnose and optimize the sustainability of a utility boiler. Seven utility boiler systems are analyzed using energy and embodied solar energy (emergy) principles in order to evaluate their environmental efficiencies. They include a subcritical coal fired boiler, a supercritical coal fired boiler, an oil fired boiler, a natural gas fired boiler, a concentrating solar power boiler utilizing a tower configuration, a biomass boiler, and a refuse derived fuel boiler. Their relative environmental impacts were compared. The results show that the natural gas boiler has significantly lower CO_2 emission than an equivalent coal or oil fired boiler. The refuse derived fuel boiler has about the same CO_2 emissions as the natural gas boiler. The emergy sustainability index of a utility boiler system is determined as the measure of its sustainability from an environmental perspective. Our analyses results indicate that the natural gas boiler has a relatively high emergy sustainability index compared to other fossil fuel boilers. Converting existing coal boilers to natural gas boilers is a feasible option to achieve better sustainability. The results also show that the biomass boiler has the best emergy sustainability index and it will remain a means to utilize the renewable energy within the Rankine steam cycle. Before

  19. Chemical cleaning of UK AGR boilers

    International Nuclear Information System (INIS)

    Rudge, A.; Turner, P.; Ghosh, S.; Clary, W.; Tice, D.R.

    2002-01-01

    For a number of years, the waterside pressure drops across the advanced gas-cooled reactor (AGR) pod boilers have been increasing. The pressure drop increases have accelerated with time, which is the converse behaviour to that expected for rippled magnetite formation (rapid initial increase slowing down with time). Nonetheless, magnetite deposition remains the most likely cause for the increasing boiler resistances. A number of potential countermeasures have been considered in response to the boiler pressure drop increases. However, there was no detectable reduction in the rate of pressure drop increase. Chemical cleaning was therefore considered and a project to substantiate and then implement chemical cleaning was initiated. (authors)

  20. Techniques for measurement of heat flux in furnace waterwalls of boilers and prediction of heat flux – A review

    International Nuclear Information System (INIS)

    Sankar, G.; Chandrasekhara Rao, A.; Seshadri, P.S.; Balasubramanian, K.R.

    2016-01-01

    Highlights: • Heat flux measurement techniques applicable to boiler water wall are elaborated. • Applications involving heat flux measurement in boiler water wall are discussed. • Appropriate technique for usage in high ash Indian coal fired boilers is required. • Usage of chordal thermocouple is suggested for large scale heat flux measurements. - Abstract: Computation of metal temperatures in a furnace waterwall of a boiler is necessary for the proper selection of tube material and thickness. An adequate knowledge of the heat flux distribution in the furnace walls is a prerequisite for the computation of metal temperatures. Hence, the measurement of heat flux in a boiler waterwall is necessary to arrive at an optimum furnace design, especially for high ash Indian coal fired boilers. Also, a thoroughly validated furnace model will result in a considerable reduction of the quantum of experimentation to be carried out. In view of the above mentioned scenario, this paper reviews the research work carried out by various researchers by experimentation and numerical simulation in the below mentioned areas: (i) furnace modeling and heat flux prediction, (ii) heat flux measurement techniques and (iii) applications of heat flux measurements.

  1. Steam generator chemical cleaning demonstration test No. 1 in a pot boiler

    International Nuclear Information System (INIS)

    Key, G.L.; Helyer, M.H.

    1981-04-01

    The effectiveness of the Electric Power Research Institute (EPRI Mark I) chemical cleaning solvent process was tested utilizing a 12 tube pot boiler that had previously been fouled and dented under 30 days of high chloride fault chemistry operation. Specifically, the intent of this chemical cleaning test was to: (1) dissolve sludge from the tubesheet, (2) remove non-protective magnetite from dented tube/support crevice regions, and (3) quantify the extent of corrosion of steam generator material during the test. Two laboratory cleaning demonstrations of 191 and 142 hours were performed

  2. NOx Control Options and Integration for US Coal Fired Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Mike Bockelie; Kevin Davis; Connie Senior Darren Shino; Dave Swenson; Larry Baxter; Calvin Bartholomew; William Hecker; Stan Harding

    2004-09-30

    This is the seventeenth Quarterly Technical Report for DOE Cooperative Agreement No: DEFC26-00NT40753. The goal of the project is to develop cost effective analysis tools and techniques for demonstrating and evaluating low NOx control strategies and their possible impact on boiler performance for boilers firing US coals. The Electric Power Research Institute (EPRI) is providing co-funding for this program. The SCR slipstream reactor was assembled and installed at Plant Gadsden this quarter. Safety equipment for ammonia had not been installed at the end of the quarter, but will be installed at the beginning of next quarter. The reactor will be started up next quarter. Four ECN corrosion probes were reinstalled at Gavin and collected corrosion data for approximately one month. Two additional probes were installed and removed after about 30 hours for future profilometry analysis. Preliminary analysis of the ECN probes, the KEMA coupons and the CFD modeling results all agree with the ultrasonic tube test measurements gathered by AEP personnel.

  3. Study of immersed heat exchange surface for high efficiency heat recovery from wire rim tires in a fluidized bed boiler; Hai tire nado kara no kokoritsu netsukaishuyo ryudosho boiler no sonai dennetsukan no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Oshita, T; Nagato, S; Miyoshi, N; Hosoda, S [Ebara Corp., Tokyo (Japan)

    1996-07-10

    In an ICFB boiler, the fluidized bed is separated by a partition into the main combustion and the heat recovery chambers. The flows in these chambers are generated by using silica sand as the fluidizing medium. To determine the overall heat transfer coefficient (HTC) of the boiler`s panel type immersed heat transfer tulles, combustion tests were performed with wire rim tires. The overall HTC of a panel tube array was lower than that of a zigzag tube arrangement. In practice, the heat absorbed by the fins makes the coefficients of either type of tube array almost identical. The air flow rate in the circulating bed at the loot Tom of the heat recovery chamber can be changed to control the overall HTC to a value virtually identical with that of a zigzag tube array. The combustion of wire rim tires leads to a buildup of wires in the zigzag array hampering the transfer of heat. Yet, the panel type array showed no buildup so that it was possible to maintain steady operation with this type of tube arrangement. 8 refs., 10 figs., 2 tabs.

  4. Slagging behavior of upgraded brown coal and bituminous coal in 145 MW practical coal combustion boiler

    Energy Technology Data Exchange (ETDEWEB)

    Akiyama, Katsuya; Pak, Haeyang; Takubo, Yoji [Kobe Steel, Ltd, Kobe (Japan). Mechanical Engineering Research Lab.; Tada, Toshiya [Kobe Steel, Ltd, Takasago (Japan). Coal and Energy Technology Dept.; Ueki, Yasuaki [Nagoya Univ. (Japan). Energy Science Div.; Yoshiie, Ryo; Naruse, Ichiro [Nagoya Univ. (Japan). Dept. of Mechanical Science and Engineering

    2013-07-01

    The purpose of this study is to quantitatively evaluate behaviors of ash deposition during combustion of Upgraded Brown Coal (UBC) and bituminous coal in a 145 MW practical coal combustion boiler. A blended coal consisting 20 wt% of the UBC and 80 wt% of the bituminous coal was burned for the combustion tests. Before the actual ash deposition tests, the molten slag fractions of ash calculated by chemical equilibrium calculations under the combustion condition was adopted as one of the indices to estimate the tendency of ash deposition. The calculation results showed that the molten slag fraction for UBC ash reached approximately 90% at 1,523 K. However, that for the blended coal ash became about 50%. These calculation results mean that blending the UBC with a bituminous coal played a role in decreasing the molten slag fraction. Next, the ash deposition tests were conducted, using a practical pulverized coal combustion boiler. A water-cooled stainless-steel tube was inserted in locations at 1,523 K in the boiler to measure the amount of ash deposits. The results showed that the mass of deposited ash for the blended coal increased and shape of the deposited ash particles on the tube became large and spherical. This is because the molten slag fraction in ash for the blended coal at 1,523 K increased and the surface of deposited ash became sticky. However, the mass of the deposited ash for the blended coal did not greatly increase and no slagging problems occurred for 8 days of boiler operation under the present blending conditions. Therefore, appropriate blending of the UBC with a bituminous coal enables the UBC to be used with a low ash melting point without any ash deposition problems in a practical boiler.

  5. Treatment of Berkeley boilers in Studsvik. Project description and experiences - Berkeley Boilers Project

    International Nuclear Information System (INIS)

    Saul, Dave; Davidson, Gavin; Wirendal, Bo

    2014-01-01

    In November 2011 Studsvik was awarded a contract to transport five decommissioned boilers from the Berkeley Nuclear Licensed Site in the UK to the Studsvik Nuclear Site in Sweden for metal treatment and recycling. A key objective of the project was to remove the boilers from the site by 31 March 2012 and this was successfully achieved with all boilers off site by 22 March and delivered to Studsvik on 6 April. In November 2012 Studsvik was awarded a further contract for the remaining ten Berkeley Boilers with the requirement to remove all boilers from the Berkeley site by 31 March 2013. Again this was successfully achieved ahead of programme with all boilers in Sweden by 1 April 2013. A total of nine boilers have now been processed and all remaining boilers will be completed by end of September 2014. The projects have had many challenges including a very tight timescale and both have been successfully delivered to cost and ahead of the baseline programme. This paper describes the project and the experience gained from treatment of the boilers to date. (authors)

  6. Multi-pressure boiler thermodynamics analysis code

    International Nuclear Information System (INIS)

    Lorenzoni, G.

    1992-01-01

    A new method and the relative FORTRAN program for the thermodynamics design analysis of a multipressure boiler are reported. This method permits the thermodynamics design optimization with regard to total exergy production and a preliminary costs

  7. New thinking for the boiler room.

    Science.gov (United States)

    Rose, Wayne

    2008-09-01

    Wayne Rose, marketing manager at integrated plant room manufacturer Armstrong Integrated Systems, explains how increasing use of off-site manufacture, the latest 3D modelling technology, and advances in control technology, are revolutionising boiler room design and construction.

  8. Pirotubular boilers design. Diseno de calderas pirotubulares

    Energy Technology Data Exchange (ETDEWEB)

    Latre Durso, F. (Geval S.A. (Spain))

    1994-01-01

    This article describes the conceptual design of Pirotubular boilers from the valuable thermal point of view, to the dimensional. This topic is a very tool valuable for professionals of design and for maintenance and operation equipment.

  9. Chemical, radiochemical and structural properties of corrosion products on CANDU monel-400 boiler surfaces

    International Nuclear Information System (INIS)

    Rummery, T.E.; Scott, G.A.; Owen, D.G.; Tremaine, R.

    1980-09-01

    The surface of the primary-coolant side of a complete Monel-400 boiler tube removed from Douglas Point Nuclear Generating Station was subjected to a detailed analysis by scanning electron microscopy, energy dispersive X-ray spectrometry, X-ray diffraction and chemical analysis. The tube had been in operation for 420 effective full-power days. The major deposits found were metallic Cu and Ni with significant amounts of NiO, and the mixed cation spinel Ni sub(x) Fe sub(3-x) O 4 . The phase compostion, 60 Co activity, and distribution of deposits in the tube are consistent with changes in the degree of supersaturation due to the temperature gradient along the tube and with the thermodynamic stability of observed phases. The morphology of the deposit is controlled by hydrodynamic effects. (auth)

  10. Catalytic burners in larger boiler appliances

    Energy Technology Data Exchange (ETDEWEB)

    Silversand, Fredrik; Persson, Mikael (Catator AB, Lund (Sweden))

    2009-02-15

    This project focuses on the scale up of a Catator's catalytic burner technology to enable retrofit installation in existing boilers and the design of new innovative combinations of catalytic burners and boilers. Different design approaches are discussed and evaluated in the report and suggestions are made concerning scale-up. Preliminary test data, extracted from a large boiler installation are discussed together with an accurate analysis of technical possibilities following an optimization of the boiler design to benefit from the advantages of catalytic combustion. The experimental work was conducted in close collaboration with ICI Caldaie (ICI), located in Verona, Italy. ICI is a leading European boiler manufacturer in the effect segment ranging from about 20 kWt to several MWt. The study shows that it is possibly to scale up the burner technology and to maintain low emissions. The boilers used in the study were designed around conventional combustion and were consequently not optimized for implementation of catalytic burners. From previous experiences it stands clear that the furnace volume can be dramatically decreased when applying catalytic combustion. In flame combustion, this volume is normally dimensioned to avoid flame impingement on cold surfaces and to facilitate completion of the gas-phase reactions. The emissions of nitrogen oxides can be reduced by decreasing the residence time in the furnace. Even with the over-dimensioned furnace used in this study, we easily reached emission values close to 35 mg/kWh. The emissions of carbon monoxide and unburned hydrocarbons were negligible (less than 5 ppmv). It is possible to decrease the emissions of nitrogen oxides further by designing the furnace/boiler around the catalytic burner, as suggested in the report. Simultaneously, the size of the boiler installation can be reduced greatly, which also will result in material savings, i.e. the production cost can be reduced. It is suggested to optimize the

  11. Boiler burden reduced at Bedford site.

    Science.gov (United States)

    Horsley, Chris

    2011-10-01

    With the NHS aiming to reduce its 2007 carbon footprint by 10% by 2015, Chris Horsley, managing director of Babcock Wanson UK, a provider of industrial boilers and burners, thermal oxidisers, air treatment, water treatment, and associated services, looks at how one NHS Trust has approached the challenge, and considerably reduced its carbon emissions, by refurbishing its boiler house and moving from oil to gas-fired steam generation.

  12. Ecological boiler modernization, feasible energy solutions

    International Nuclear Information System (INIS)

    Krcek, F.; Matev, M.; Sykora, J.; Chladek, J.

    2005-01-01

    Alstom Power, s.r.o., ALSTOM GROUP in Brno, Czech Republic is a successor of PBS (First Brno Machine Works). PBS was a well-known company in Bulgaria - mainly as Heating Power Plant (HPP) and Industrial Plant supplier of boilers, industrial steam turbines, milling systems, heat exchangers Btc. PBS has been privatised in two stages starting at1993 year. Alstom recently deals with boiler and heat exchanger products. Industrial turbine but has been sold to Siemens in 2004

  13. Gas fired boilers and atmospheric pollution

    International Nuclear Information System (INIS)

    Chiaranello, J.M.

    1991-01-01

    A general analysis concerning atmospheric pollution is presented: chemical composition and vertical distribution of atmosphere and pollutants, chemical reactions, ozone destruction and production cycles, COx, NOx and SOx pollutions. The gas fired boiler number and repartition in France are presented and the associated pollution is analyzed (CO2, CO, NOx) and quantified. Various pollution control technics concerning gas fired boiler pollutants are described and a pollution criterion for clean gas fired generators is proposed

  14. Assessment of physical workload in boiler operations.

    Science.gov (United States)

    Rodrigues, Valéria Antônia Justino; Braga, Camila Soares; Campos, Julio César Costa; Souza, Amaury Paulo de; Minette, Luciano José; Sensato, Guilherme Luciano; Moraes, Angelo Casali de; Silva, Emília Pio da

    2012-01-01

    The use of boiler wood-fired is fairly common equipment utilized in steam generation for energy production in small industries. The boiler activities are considered dangerous and heavy, mainly due to risks of explosions and the lack of mechanization of the process. This study assessed the burden of physical labor that operators of boilers are subjected during the workday. Assessment of these conditions was carried out through quantitative and qualitative measurements. A heart rate monitor, a wet-bulb globe thermometer (WBGT), a tape-measure and a digital infrared camera were the instruments used to collect the quantitative data. The Nordic Questionnaire and the Painful Areas Diagram were used to relate the health problems of the boiler operator with activity. With study, was concluded that the boiler activity may cause pains in the body of intensity different, muscle fatigue and diseases due to excessive weight and the exposure to heat. The research contributed to improve the boiler operator's workplace and working conditions.

  15. Boiler referruling on the Hartlepool and Heysham 1 advanced gas-cooled reactors

    International Nuclear Information System (INIS)

    Newell, J.E.

    1988-01-01

    The Hartlepool and Heysham I reactors each use eight cylindrical boilers having nineteen rows of helical tubes. The advantages of this design are partially offset by the relatively poor radial gas mixing. Some rows of tubing may have an imbalance between heat input from the gas and the flow of feedwater. causing a temperature profile at the upper transition joints. The thermal/hydraulic behaviour meant that the metallurgical constraints limited output. Analysis of the behaviour of these boilers required a new two-dimensional mathematical model, known as PODMIX. This describes the thermal hydraulics in each of the rows of tubing and also in the gas between the rows. Not all of the parameters for the model can be determined from first principles. However, two out of the thirty two pods have thermocouples at some of the upper transition joints and these made back calculation possible. In order to translate this model to other boiler pods, a novel thermocouple rake system was designed for sampling superheated steam temperatures in selected tubes. A result of this analysis was to show that different, individual ferrule patterns were needed for each pod. The characteristics could, in general, best be met using twin orifice ferrules. Unfortunately, the installed system did not permit the replacement of orifices, so that a completely new system had to be developed. In the course of designing this, the opportunity was taken to over come susceptibilities to erosion/corrosion and crevice corrosion. Removal of the old ferrules and replacement with the new ones necessitated the development of high precision, programmable machines to operate under difficult site conditions. These carried out drilling, boring, grinding and polishing operations as well as making face welds and tube bore welds. Modifications have already achieved substantial improvements in performance and output, but an extended, iterative programme still lies ahead. (author)

  16. Advanced Ultrasupercritical (AUSC) Tube Membrane Panel Development

    Energy Technology Data Exchange (ETDEWEB)

    Pschirer, James [Alstom Power Inc., Windsor, CT (United States); Burgess, Joshua [Alstom Power Inc., Windsor, CT (United States); Schrecengost, Robert [Alstom Power Inc., Windsor, CT (United States)

    2017-08-16

    Alstom Power Inc., a wholly owned subsidiary of the General Electric Company (GE), has completed the project “Advanced Ultrasupercritical (AUSC) Tube Membrane Panel Development” under U.S. Department of Energy (DOE) Award Number DE-FE0024076. This project was part of DOE’s Novel Crosscutting Research and Development to Support Advanced Energy Systems program. AUSC Tube Membrane Panel Development was a two and one half year project to develop and verify the manufacturability and serviceability of welded tube membrane panels made from high performance materials suitable for the AUSC steam cycles, defined as high pressure steam turbine inlet conditions of 700-760°C (1292-1400°F) and 24.5-35MPa (3500-5000psi). The difficulty of this challenge lies in the fact that the membrane-welded construction imposes demands on the materials that are unlike any that exist in other parts of the boiler. Tube membrane panels have been designed, fabricated, and installed in boilers for over 50 years with relatively favorable experience when fabricated from carbon and Cr-Mo low alloy steels. The AUSC steam cycle requires membrane tube panels fabricated from materials that have not been used in a weldment with metal temperatures in the range of 582-610°C (1080-1130°F). Fabrication materials chosen for the tubing were Grade 92 and HR6W. Grade 92 is a creep strength enhanced ferritic Cr-Mo alloy and HR6W is a high nickel alloy. Once the materials were chosen, GE performed the engineering design of the panels, prepared shop manufacturing drawings, and developed manufacturing and inspection plans. After the materials were purchased, GE manufactured and inspected the tube membrane panels, determined if post fabrication heat treatment of the tube membrane panels was needed, performed pre- and post-weld heat treatment on the Grade 92 panels, conducted final nondestructive inspection of any heat treated tube membrane panels, conducted destructive inspection of the completed tube

  17. Development of pressurized internally circulating fluidized bed combustion technology; Kaatsu naibu junkan ryudosho boiler no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Ishihara, I [Center for Coal Utilization, Japan, Tokyo (Japan); Nagato, S; Toyoda, S [Ebara Corp., Tokyo (Japan)

    1996-09-01

    The paper introduced support research on element technology needed for the design of hot models of the pressurized internally circulating fluidized bed combustion boiler in fiscal 1995 and specifications for testing facilities of 4MWt hot models after finishing the basic plan. The support research was conduced as follows: (a) In the test for analysis of cold model fluidization, it was confirmed that each characteristic value of hot models is higher than the target value. Further, calculation parameters required for computer simulation were measured and data on the design of air diffusion nozzle for 1 chamber wind box were sampled. (b) In the CWP conveyance characteristic survey, it was confirmed that it is possible to produce CWP having favorable properties. It was also confirmed that favorable conveyability can be maintained even if the piping size was reduced down to 25A. (c) In the gas pressure reducing test, basic data required for the design of gas pressure reducing equipment were sampled. Specifications for the fluidized bed combustion boiler of hot models are as follows: evaporation amount: 3070kg/h, steam pressure: 1.77MPa, fuel supply amount: 600kg-coal/h, boiler body: cylinder shape water tube internally circulating fluidized bed combustion boiler. 4 refs., 4 figs.

  18. Initial study of a method for IR measurements in boilers; Inledande studie av metod foer IR-maetning i aangpannor

    Energy Technology Data Exchange (ETDEWEB)

    Sandberg, Martin; Joensson, Magnus; Lundin, Leif [Swedish National Testing and Research Inst., Boraas (Sweden)

    1999-10-01

    The tubes in steam boilers are required to be regularly inspected, in order to find water-side deposits, thinning of walls or material defects. This is for safety, problem-free operation and high availability. No non-destructive method of inspection is available today for finding deposits on the insides of boiler tubes. Nor is there any method that can not only detect deposits on the insides of the tubes but also monitor the tubes' wall thicknesses. A suitable method - reliable, safe, easy to use and cost-efficient - is therefore needed. One such method is to measure the surface temperature of a larger area of the diaphragm wall, using a non-contact method, and from the resulting information to assess the material thickness and possible water-side or steam-side deposits. An IR camera is used for non-contact measurement of the radiated energy from several adjacent surface elements, and thus also of their temperature. The temperature is displayed on the camera's screen to produce a picture of the temperature distribution. This is a well-established method today, and is used in applications such as the steel industry, the electricity industry, electronics and health care. The surface temperatures of the tube walls can be measured by inserting an IR camera on an arm into the combustion chamber, without anyone having to get inside the boiler. The combustion chamber is the part of the boiler that is of main interest for inspection, as it is the easiest to reach. Measurements are facilitated by higher temperatures and thus higher heat fluxes through the tube walls. Diaphragm wall temperatures can be measured quickly and rationally over large areas. Points of interest in inspections include determining where there are water-side deposits in the tubes, where tubes are thin, where flow is obstructed and where there might be material defects. With the exception of material defects, all of these mechanisms result in changes in the surface temperature, which in many

  19. Pelly Crossing wood chip boiler

    Energy Technology Data Exchange (ETDEWEB)

    1985-03-11

    The Pelly wood chip project has demonstrated that wood chips are a successful fuel for space and domestic water heating in a northern climate. Pelly Crossing was chosen as a demonstration site for the following reasons: its extreme temperatures, an abundant local supply of resource material, the high cost of fuel oil heating and a lack of local employment. The major obstacle to the smooth operation of the boiler system was the poor quality of the chip supply. The production of poor quality chips has been caused by inadequate operation and maintenance of the chipper. Dull knives and faulty anvil adjustments produced chips and splinters far in excess of the one centimetre size specified for the system's design. Unanticipated complications have caused costs of the system to be higher than expected by approximately $15,000. The actual cost of the project was approximately $165,000. The first year of the system's operation was expected to accrue $11,600 in heating cost savings. This estimate was impossible to confirm given the system's irregular operation and incremental costs. Consistent operation of the system for a period of at least one year plus the installation of monitoring devices will allow the cost effectiveness to be calculated. The wood chip system's impact on the environment was estimated to be minimal. Wood chip burning was considered cleaner and safer than cordwood burning. 9 refs., 6 figs., 6 tabs.

  20. Superheater Corrosion In Biomass Boilers: Today's Science and Technology

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, William (Sandy) [SharpConsultant

    2011-12-01

    This report broadens a previous review of published literature on corrosion of recovery boiler superheater tube materials to consider the performance of candidate materials at temperatures near the deposit melting temperature in advanced boilers firing coal, wood-based fuels, and waste materials as well as in gas turbine environments. Discussions of corrosion mechanisms focus on the reactions in fly ash deposits and combustion gases that can give corrosive materials access to the surface of a superheater tube. Setting the steam temperature of a biomass boiler is a compromise between wasting fuel energy, risking pluggage that will shut the unit down, and creating conditions that will cause rapid corrosion on the superheater tubes and replacement expenses. The most important corrosive species in biomass superheater corrosion are chlorine compounds and the most corrosion resistant alloys are typically FeCrNi alloys containing 20-28% Cr. Although most of these materials contain many other additional additions, there is no coherent theory of the alloying required to resist the combination of high temperature salt deposits and flue gases that are found in biomass boiler superheaters that may cause degradation of superheater tubes. After depletion of chromium by chromate formation or chromic acid volatilization exceeds a critical amount, the protective scale gives way to a thick layer of Fe{sub 2}O{sub 3} over an unprotective (FeCrNi){sub 3}O{sub 4} spinel. This oxide is not protective and can be penetrated by chlorine species that cause further acceleration of the corrosion rate by a mechanism called active oxidation. Active oxidation, cited as the cause of most biomass superheater corrosion under chloride ash deposits, does not occur in the absence of these alkali salts when the chloride is present as HCl gas. Although a deposit is more corrosive at temperatures where it is molten than at temperatures where it is frozen, increasing superheater tube temperatures through

  1. The effect of water quality on reliability of boiler plants performance

    Directory of Open Access Journals (Sweden)

    Gajić Anto S.

    2010-01-01

    Full Text Available This paper presents sources and types of corrosion processes of boiler tube system of the Thermal Power Plant "Ugljevik". The main goal in the electric power production is to achieve lower prices, which can only be done by providing low maintenance costs. While it is not possible to completely stop corrosion, it could be slowed down and it's effects could be reduced. In order to reduce corrosion to a minimum on thermal power plants' vital equipment, particularly boilers, it is necessary to determine in each particular case the acting mechanism of corrosion and agents that cause it. Damages and failures on thermal power plants are largely caused by the development of various types of corrosion processes. Special attention is given to the preparation of water, considering its importance to the occurrence of corrosion. The following types of corrosion were detected on the screen tube boiler by visual examination on the side of water and steam: erosive, pitting and impact corrosion. The inner surface of screen pipes, from which the scale layer was removed, indicates that the erosive corrosion with the thinning of pipe walls occurs. Perforation of the welded screen pipes shows that stress corrosion occurred on the screen pipe with formation of cracks and that pipe exploded. Pits on the inner surface of the screen pipes, visible after the removal of scale and corrosion products, are proof that pitting corrosion occurred. The causes of corrosion were discovered and proposed measures for their elimination were given.

  2. Loss of feed flow, steam generator tube rupture and steam line break thermohydraulic experiments

    Energy Technology Data Exchange (ETDEWEB)

    Mendler, O J; Takeuchi, K; Young, M Y

    1986-10-01

    The Westinghouse Model Boiler No. 2 (MB-2) steam generator test model at the Engineering Test Facility in Tampa, Florida, was reinstrumented and modified for performing a series of tests simulating steam generator accident transients. The transients simulated were: loss of feed flow, steam generator tube rupture, and steam line break events. This document presents a description of (1) the model boiler and the associated test facility, (2) the tests performed, and (3) the analyses of the test results.

  3. Loss of feed flow, steam generator tube rupture and steam line break thermohydraulic experiments

    International Nuclear Information System (INIS)

    Mendler, O.J.; Takeuchi, K.; Young, M.Y.

    1986-10-01

    The Westinghouse Model Boiler No. 2 (MB-2) steam generator test model at the Engineering Test Facility in Tampa, Florida, was reinstrumented and modified for performing a series of tests simulating steam generator accident transients. The transients simulated were: loss of feed flow, steam generator tube rupture, and steam line break events. This document presents a description of (1) the model boiler and the associated test facility, (2) the tests performed, and (3) the analyses of the test results

  4. Feedwater heater tube-to-tubesheet connections

    International Nuclear Information System (INIS)

    Yokell, S.

    1993-01-01

    This paper discusses some practical aspects of expanded, welded, and welded-and-expanded feedwater heater tube-to-tubesheet joints. It outlines elastic-plastic tube expanding theory. It examines uniform-pressure-expanded tube joint strength and correlating roller-expanded joint strength with wall reduction and rolling torque. For materials subject to stress-corrosion cracking (SCC), it recommends heat treating tube ends before expanding. For materials subject to fatigue and tube-end cracking, it advocates two-stage expanding: (1) expanding enough to create firm tube-hole contact over the full tubesheet thickness; and (2) re-expanding at full pressure or torque. The paper emphasizes the desirability of segregating heats of tubing, mapping the tube-heat locations and making the heat map a permanent part of the heater maintenance file. It recommends when to provide TEMA/HEI Power Plant Standard annular grooves for roller-expanding and provides an equation for determining optimum groove width for uniform-pressure expanding. The paper also reviews welding requirements for welds of tubes to tubesheets. The review covers front-face welding before and after expanding and the reasons for welding first. It outlines current thinking about definitions of strength- and seal-welds of front-face welded joint in terms of their functions and load-carrying abilities. It presents a proposal for determining the required size of strength welds for use in Section VIII of the ASME Boiler and Pressure Vessel Code (the Code). It shows why welded-and-expanded feedwater heater tube-to-tubesheet joints should be full-strength and full-depth expanded. It makes recommendations for pressure- and leak-testing. This work also proposes the industry consider butt welding the tubes to the steam-side face of the tubesheet as a regular method of tube joining. The results of a survey of manufacturers practices are appended. 30 refs., 14 figs

  5. Boiler house modernization through shared savings program

    Energy Technology Data Exchange (ETDEWEB)

    Breault, R.W. [Tecogen, Waltham, MA (United States)

    1995-12-31

    Throughout Poland as well as the rest of Eastern Europe, communities and industries rely on small heat only boilers to provide district and process heat. Together these two sectors produce about 85,000 MW from boilers in the 2 to 35 MW size range. The bulk of these units were installed prior to 1992 and must be completely overhauled to meet the emission regulations which will be coming into effect on January 1, 1998. Since the only practical fuel is coal in most cases, these boilers must be either retrofit with emission control technology or be replaced entirely. The question that arises is how to accomplish this given the current tight control of capital in Poland and other East European countries. A solution that we have for this problem is shared savings. These boilers are typically operating with a quiet low efficiency as compared to western standards and with excessive manual labor. Installing modernization equipment to improve the efficiency and to automate the process provides savings. ECOGY provides the funds for the modernization to improve the efficiency, add automation and install emission control equipment. The savings that are generated during the operation of the modernized boiler system are split between the client company and ECOGY for a number of years and then the system is turned over in entirety to the client. Depending on the operating capacity, the shared savings agreement will usually span 6 to 10 years.

  6. The load structure of electro boilers

    International Nuclear Information System (INIS)

    Feilberg, N.; Livik, K.

    1995-01-01

    Load measurements have been performed on 24 electro boilers with a time resolution of one hour throughout a period of one year. The boilers are used for space heating and heating of tap water in office buildings, shopping centres and apartment buildings. All boilers have tariffs with disconnection agreements. This report presents load analyses of the measurements from each boiler, and typical load profiles are calculated and presented. It also analyses how boilers are used in relation to the outdoor temperature and the power price on the spot market. All the measurements are performed in Bergen, Norway, in the period August 1993 - August 1994. Typical load profiles are shown, both annual and daily, as well as specific load parameters in addition to key figures used in calculating the total power load on the distribution network. The climate impact on energy and power load is evaluated. The report also shows examples of how the results may be applied in various special fields. 8 figs., 9 tabs

  7. Increasing the efficiency of the condensing boiler

    Science.gov (United States)

    Zaytsev, ON; Lapina, EA

    2017-11-01

    Analysis of existing designs of boilers with low power consumption showed that the low efficiency of the latter is due to the fact that they work in most cases when the heating period in the power range is significantly less than the nominal power. At the same time, condensing boilers do not work in the most optimal mode (in condensing mode) in the central part of Russia, a significant part of their total operating time during the heating season. This is due to existing methods of equipment selection and joint operation with heating systems with quantitative control of the coolant. It was also revealed that for the efficient operation of the heating system, it is necessary to reduce the inertia of the heat generating equipment. Theoretical patterns of thermal processes in the furnace during combustion gas at different radiating surfaces location schemes considering the influence of the very furnace configuration, characterized in that to reduce the work condensing boiler in conventional gas boiler operation is necessary to maintain a higher temperature in the furnace (in the part where spiral heat exchangers are disposed), which is possible when redistributing heat flow - increase the proportion of radiant heat from the secondary burner emitter allow Perey For the operation of the condensing boiler in the design (condensation) mode practically the entire heating period.

  8. Sodium reflux pool-boiler solar receiver on-sun test results

    Energy Technology Data Exchange (ETDEWEB)

    Andraka, C E; Moreno, J B; Diver, R B; Moss, T A [Oak Ridge National Lab., TN (United States)

    1992-06-01

    The efficient operation of a Stirling engine requires the application of a high heat flux to the relatively small area occupied by the heater head tubes. Previous attempts to couple solar energy to Stirling engines generally involved directly illuminating the heater head tubes with concentrated sunlight. In this study, operation of a 75-kW{sub t} sodium reflux pool-boiler solar receiver has been demonstrated and its performance characterized on Sandia's nominal 75-kW{sub t} parabolic-dish concentrator, using a cold-water gas-gap calorimeter to simulate Stirling engine operation. The pool boiler (and more generally liquid-metal reflux receivers) supplies heat to the engine in the form of latent heat released from condensation of the metal vapor on the heater head tubes. The advantages of the pool boiler include uniform tube temperature, leading to longer life and higher temperature available to the engine, and decoupling of the design of the solar absorber from the engine heater head. The two-phase system allows high input thermal flux, reducing the receiver size and losses, therefore improving system efficiency. The receiver thermal efficiency was about 90% when operated at full power and 800{degree}C. Stable sodium boiling was promoted by the addition of 35 equally spaced artificial cavities in the wetted absorber surface. High incipient boiling superheats following cloud transients were suppressed passively by the addition of small amounts of xenon gas to the receiver volume. Stable boiling without excessive incipient boiling superheats was observed under all operating conditions. The receiver developed a leak during performance evaluation, terminating the testing after accumulating about 50 hours on sun. The receiver design is reported here along with test results including transient operations, steady-state performance evaluation, operation at various temperatures, infrared thermography, x-ray studies of the boiling behavior, and a postmortem analysis.

  9. Thermal load non-uniformity estimation for superheater tube bundle damage evaluation

    Directory of Open Access Journals (Sweden)

    Naď Martin

    2018-01-01

    Full Text Available Industrial boiler damage is a common phenomenon encountered in boiler operation which usually lasts several decades. Since boiler shutdown may be required because of localized failures, it is crucial to predict the most vulnerable parts. If damage occurs, it is necessary to perform root cause analysis and devise corrective measures (repairs, design modifications, etc.. Boiler tube bundles, such as those in superheaters, preheaters and reheaters, are the most exposed and often the most damaged boiler parts. Both short-term and long-term overheating are common causes of tube failures. In these cases, the design temperatures are exceeded, which often results in decrease of remaining creep life. Advanced models for damage evaluation require temperature history, which is available only in rare cases when it has been measured and recorded for the whole service life. However, in most cases it is necessary to estimate the temperature history from available operation history data (inlet and outlet pressures and temperatures etc.. The task may be very challenging because of the combination of complex flow behaviour in the flue gas domain and heat transfer phenomena. This paper focuses on estimating thermal load non-uniformity on superheater tubes via Computational Fluid Dynamics (CFD simulation of flue gas flow including heat transfer within the domain consisting of a furnace and a part of the first stage of the boiler.

  10. Safety issues arising from the corrosion-fatigue of waterwall tubes

    Energy Technology Data Exchange (ETDEWEB)

    Brear, J. M.; Jarvis, P. (Stress Engineering Services (Europe) Limited, Chichester (United Kingdom)); Scully, S. (Electricity Supply Board, Dublin (Ireland))

    2010-05-15

    An incidence of waterwall tube failures, one leading to a significant steam release external to the boiler, has highlighted the need for rigorous risk assessment of such events. Initial review of the utility's experience revealed one of their boiler designs as having had a greater incidence of corrosion-fatigue issues in waterwall tubing than the others. These units were treated as a priority. To address failure likelihood, fracture mechanics calculations were performed. These studies defined the necessary inspection coverage and sensitivity required to underwrite safe operation at various potential loads. Personnel safety was considered the most important consequence of failure. Accordingly, potential steam releases were modelled to define safe exclusion zones within the boiler house. Standard calculations were found to be nonconservative; more exact formulae were needed to give realistic results. Using the results of these studies, the utility was able to draw up a realistic inspection plan. Safe operating pressures and appropriate exclusion zones were defined for each boiler, and for a range of operational scenarios. These tactics have allowed the utility to inspect the boilers in turn and to repair all significant defects in the waterwall tubes, whilst maintaining a good overall power output. In parallel, a root-cause investigation was performed to identify the factors contributing to the failures. Where possible, causative influences were reduced or mitigated so as to reduce the likelihood of failure whilst allowing increased flexibility of boiler operation. (orig.)

  11. ENVIRONMENTAL ASPECTS OF MODERNIZATION OF HIGH POWER WATER-HEATING BOILERS

    Directory of Open Access Journals (Sweden)

    P. M. Glamazdin

    2016-01-01

    Full Text Available Boilers of KVGM and PTVM series are characterized by high values of NOx and CO content in the combustion products. Reduction of NOx and CO content can be achieved by two ways: by installing the condensing heat recovery unit at the boiler outlet and by improving the heat and mass transfer processes in boiler furnaces. Application of the condensing heat recovery units causes pollution of resulting condensate by low-concentration acids. The authors conducted a study in order to determine the effectiveness of the previously applied methods of suppressing the emission of nitrogen oxides in the boilers of these types. Equalization of the temperature field and, consequently, enhancement of heat transfer in the furnace by substitution the used burners by the more advanced ones, the design of which facilitates reduction the emission of nitrogen oxides, were applied to all the upgraded facilities. The studies fulfilled demonstrate that a reduction of NOx emissions in water-heating high power boilers is fairly possible by means of modernization of the latter. The authors have developed the project of the PTVM-30 boiler modernization, which was implemented at a large boiler plant in the city of Vinnitsa (Ukraine. The project included a number of technical solutions. Six burners were replaced by the two ones that were located in the hearth; also the hearth screen was dismantled. At the same time, reducing the total surface area of the heating caused by the exclusion of hearth screen was compensated by filling the locations of the six embrasures of staff burners on the side screens with straightened furnace tubes. Installing the burners separate from the screen made it possible to eliminate the transfer of vibration to the furnace tubes, and – via them – to the boilers setting. Automation provided “associated regulations”. Draught machines were equipped with frequency regulators. During commissioning of the boiler the studies were carried out that

  12. 46 CFR 52.25-5 - Miniature boilers (modifies PMB-1 through PMB-21).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Miniature boilers (modifies PMB-1 through PMB-21). 52.25... ENGINEERING POWER BOILERS Other Boiler Types § 52.25-5 Miniature boilers (modifies PMB-1 through PMB-21). Miniature boilers must meet the applicable provisions in this part for the boiler type involved and the...

  13. Model-Based Water Wall Fault Detection and Diagnosis of FBC Boiler Using Strong Tracking Filter

    Directory of Open Access Journals (Sweden)

    Li Sun

    2014-01-01

    Full Text Available Fluidized bed combustion (FBC boilers have received increasing attention in recent decades. The erosion issue on the water wall is one of the most common and serious faults for FBC boilers. Unlike direct measurement of tube thickness used by ultrasonic methods, the wastage of water wall is reconsidered equally as the variation of the overall heat transfer coefficient in the furnace. In this paper, a model-based approach is presented to estimate internal states and heat transfer coefficient dually from the noisy measurable outputs. The estimated parameter is compared with the normal value. Then the modified Bayesian algorithm is adopted for fault detection and diagnosis (FDD. The simulation results demonstrate that the approach is feasible and effective.

  14. Fiber Bragg Grating Array as a Quasi Distributed Temperature Sensor for Furnace Boiler Applications

    Science.gov (United States)

    Reddy, P. Saidi; Prasad, R. L. N. Sai; Sengupta, D.; Shankar, M. Sai; Srimannarayana, K.; Kishore, P.; Rao, P. Vengal

    2011-10-01

    This paper presents the experimental work on distributed temperature sensing making use of Fiber Bragg grating (FBG) array sensor for possible applications in the monitoring of temperature profile in high temperature boilers. A special sensor has been designed for this purpose which consists of four FBGs (of wavelengths λB1 = 1547.28 nm, λB2 = 1555.72 nm, λB3 = 1550.84 nm, λB4 = 1545.92 nm) written in hydrogen loaded fiber in line with a spacing of 15 cm between them. All the FBGs are encapsulated inside a stainless steel tube for avoiding micro cracks using rigid probe technique. The spatial distribution of temperature profile inside a prototype boiler has been measured experimentally both in horizontal and vertical directions employing the above sensor and the results are presented.

  15. Performance evaluation of a biomass boiler on the basis of heat loss method and total heat values of steam

    International Nuclear Information System (INIS)

    Munir, A.; Alvi, J.Z.; Ashfaq, S.; Ghafoor, A.

    2014-01-01

    Pakistan being an agricultural country has large resources of biomass in the form of crop residues like wood, wheat straw, rice husk, cotton sticks and bagasse. Power generation using biomass offers an excellent opportunity to overcome current scenario of energy crises. Of the all biomass resources, bagasse is one of the potential energy sources which can be successfully utilized for power generation. During the last decade, bagasse fired boilers attained major importance due to increasing prices of primary energy (e.g. fossil fuels). Performance of a bagasse fired boiler was evaluated at Shakarganj Sugar Mill, Bhone-Jhang having steam generation capacity of 80 tons h/sup -1/at 25 bar working pressure. The unit was forced circulation and bi-drum type water tube boiler which was equipped with all accessories like air heater, economizer and super-heater. Flue gas analyzer and thermocouples were used to record percent composition and temperature of flue gases respectively. Physical analysis of bagasse showed gross calorific value of bagasse as 2326 kCal kg/sup -1/. Ultimate analysis of bagasse was performed and the actual air supplied to the boiler was calculated to be 4.05 kg per kg of bagasse under the available resources of the plant. Performance evaluation of the boiler was carried out and a complete heat balance sheet was prepared to investigate the different sources of heat losses. The efficiency of the boiler was evaluated on the basis of heat losses through boiler and was found to be 56.08%. It was also determined that 2 kg of steam produced from 1 kg of bagasse under existing condition of the boiler. The performance evaluation of the boiler was also done on the basis of total heat values of steam and found to be 55.98%. The results obtained from both the methods were found almost similar. Effects of excess air, stack and ambient temperature on the efficiency of boiler have also been evaluated and presented in the manuscript. (author)

  16. Evaluation of thermal overload in boiler operators.

    Science.gov (United States)

    Braga, Camila Soares; Rodrigues, Valéria Antônia Justino; Campos, Julio César Costa; de Souza, Amaury Paulo; Minette, Luciano José; de Moraes, Angêlo Casali; Sensato, Guilherme Luciano

    2012-01-01

    The Brazilians educational institutions need a large energy demand for the operation of laundries, restaurants and accommodation of students. Much of that energy comes from steam generated in boilers with wood fuel. The laboral activity in boiler may present problems for the operator's health due to exposure to excessive heat, and its operation has a high degree of risk. This paper describes an analysis made the conditions of thermal environment in the operation of a B category boiler, located at a Higher Education Institution, located in the Zona da Mata Mineira The equipments used to collect data were Meter WBGT of the Heat Index; Meter of Wet Bulb Index and Globe Thermometer (WBGT); Politeste Instruments, an anemometer and an Infrared Thermometer. By the application of questionnaires, the second phase consisted of collecting data on environmental factors (temperature natural environment, globe temperature, relative humidity and air velocity). The study concluded that during the period evaluated, the activity had thermal overload.

  17. Improvement of efficiency by proportional and integral control for compact boiler; Shoyoryo boiler no renzoku seigyo (P.I seigyo) ni yoru seino kaizen

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, T. [Kawasaki Thermal Engineering Co. Ltd., Shiga (Japan)

    1998-10-01

    Efficiency of a compact boiler is improved by the introduction of a continuous P.I. control. It is controlled by the following procedure. The proportional control, which controls magnitude of combustion in proportion to a load requirement, is combined with an integral control function which keeps steam pressure at a given level, in order to stabilize steam pressure at a level comparable to that of a large, water-tube type boiler. A stable steam pressure is realized by including control of make-up water supply, to minimize the effects of water supply on steam pressure. The effects of characteristics of the combustion valve on control are relaxed by programming. In addition to the above, rotational speed of the motor for the forced draft fan is controlled for each load level, to reduce power consumption. These bring improved quality of steam, i.e., stabilized steam pressure, improved follow-up characteristics of the steam and secured dryness of the steam. Energy-saving is also achieved, i.e., reduction of noise and power consumption at a low combustion load are achieved by improved real boiler efficiency and inverter-aided control of the forced draft fan. Low-NOx burners are adopted, to abate NOx content to 60ppm or less at any load. 16 figs.

  18. 46 CFR 61.05-20 - Boiler safety valves.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Boiler safety valves. 61.05-20 Section 61.05-20 Shipping... INSPECTIONS Tests and Inspections of Boilers § 61.05-20 Boiler safety valves. Each safety valve for a drum, superheater, or reheater of a boiler shall be tested at the interval specified by table 61.05-10. [CGD 95-028...

  19. Application of GPRS and GIS in Boiler Remote Monitoring System

    OpenAIRE

    Hongchao Wang; Yifeng Wu

    2012-01-01

    Application of GPRS and GIS in boiler remote monitoring system was designed in this paper by combining the advantage of GPRS and GIS in remote data transmission with configuration monitoring technology. The detail information of the operating conditions of the industrial boiler can be viewed by marking the location of boiler on the electronic map dynamically which can realize the unified management for industrial boiler of a region or city conveniently. Experimental application show that the ...

  20. Feeding Tubes

    Science.gov (United States)

    ... feeding therapies have been exhausted. Please review product brand and method of placement carefully with your physician ... Total Parenteral Nutrition. Resources: Oley Foundation Feeding Tube Awareness Foundation Children’s Medical Nutrition Alliance APFED’s Educational Webinar ...

  1. Developing trends with boiler operation and management

    Energy Technology Data Exchange (ETDEWEB)

    Stark, J.M. [Occupational Safety and Health Service, Wellington (New Zealand). Dept. of Labour, Engineering Safety Branch

    1993-12-31

    Over recent years there have been many improvements in boiler control and safety management systems. Technology has made major advances and is now regarded as being well proven in Australia, Europe and the United Kingdom and these changes have been examined by a project committee, convened for the purpose, to establish whether they are equally applicable in New Zealand. The result of the committee`s findings and experience is contained in the `Draft Code of Practice`. This paper explains the development of the `Code of Practice`, the reasoning behind some of the decisions taken and the implications of these changes to boiler owners.

  2. Optimal load allocation of multiple fuel boilers.

    Science.gov (United States)

    Dunn, Alex C; Du, Yan Yi

    2009-04-01

    This paper presents a new methodology for optimally allocating a set of multiple industrial boilers that each simultaneously consumes multiple fuel types. Unlike recent similar approaches in the utility industry that use soft computing techniques, this approach is based on a second-order gradient search method that is easy to implement without any specialized optimization software. The algorithm converges rapidly and the application yields significant savings benefits, up to 3% of the overall operating cost of industrial boiler systems in the examples given and potentially higher in other cases, depending on the plant circumstances. Given today's energy prices, this can yield significant savings benefits to manufacturers that raise steam for plant operations.

  3. Firewood boiler operators and heat exposure

    Directory of Open Access Journals (Sweden)

    Vilson Bernardo Stollmeier

    2017-12-01

    Full Text Available This article presents an analysis of heat exposure work in boiler industry wood from a company in the industrial sector, focusing on the analysis of the environmental burden of the activity. Therefore, the methodological procedures consisted of document analysis, interviews, filming, evaluation problems of the effects of the hot environment and its prevention. The results show that the fuel to the boiler operators are exposed to heat and need guidance on their daily activities with prevention of diseases affected by excessive heat. Are also suggested training in technical and health to improve working conditions and the operator's health.

  4. Boiler inspection manipulator for Torness Power Station

    International Nuclear Information System (INIS)

    Carrey, R.T.A.; Yule, I.Y.; Sibson, S.; Playle, M.J.

    1996-01-01

    The Advanced Gas-cooled Reactors at Torness and Heysham 2 are provided with dedicated access for remote inspection equipment. These in-service inspection (ISI) accesses comprise 12 penetrations above the core for inspection of the above core area and boilers, 12 below core penetrations for inspection of the lower boiler area and access through any of the 8 gas circulator penetrations for inspection of the sub-diagrid area. This paper describes a manipulator which will access the reactor from above the core via any of the 8 peripheral penetrations. (UK)

  5. TA-2 Water Boiler Reactor Decommissioning Project

    International Nuclear Information System (INIS)

    Durbin, M.E.; Montoya, G.M.

    1991-06-01

    This final report addresses the Phase 2 decommissioning of the Water Boiler Reactor, biological shield, other components within the biological shield, and piping pits in the floor of the reactor building. External structures and underground piping associated with the gaseous effluent (stack) line from Technical Area 2 (TA-2) Water Boiler Reactor were removed in 1985--1986 as Phase 1 of reactor decommissioning. The cost of Phase 2 was approximately $623K. The decommissioning operation produced 173 m 3 of low-level solid radioactive waste and 35 m 3 of mixed waste. 15 refs., 25 figs., 3 tabs

  6. Experience gained from shifting a PK-19 boiler to operate with increased superheating and with a load higher than its rated value

    Science.gov (United States)

    Kholshchev, V. V.

    2011-08-01

    Failures of steam superheater tubes occurred after the boiler was shifted to operate with a steam temperature of 540°C. The operation of the steam superheater became more reliable after it had been subjected to retrofitting. The modernization scheme is described. An estimate is given to the temperature operating conditions of tubes taking into account the thermal-hydraulic nonuniformity of their heating.

  7. 46 CFR 56.50-30 - Boiler feed piping.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Boiler feed piping. 56.50-30 Section 56.50-30 Shipping... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-30 Boiler feed piping. (a) General... least two separate means of supplying feed water for the boilers. All feed pumps shall be fitted with...

  8. Biomass boiler conversion potential in the eastern United States

    Science.gov (United States)

    Charles D. Ray; Li Ma; Thomas Wilson; Daniel Wilson; Lew McCreery; Janice K. Wiedenbeck

    2013-01-01

    The U.S. is the world's leading consumer of primary energy. A large fraction of this energy is used in boiler installations to generate steam and hot water for heating applications. It is estimated there are total 163,000 industrial and commercial boilers in use in the United States of all sizes. This paper characterizes the commercial and industrial boilers in...

  9. New materials for boilers in USC power plants

    International Nuclear Information System (INIS)

    Hong, Sung Ho; Hong, Seok Joo

    2003-01-01

    The efficiency of boiler in fossil power plants is a strong function of steam temperature and pressure. Thus, the main technology of increasing boiler efficiency is the development of stronger high temperature materials, capable of operating under high stresses at ever increasing temperature. This paper will presents the new material relating to boiler of USC power plant

  10. 46 CFR 176.812 - Pressure vessels and boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Pressure vessels and boilers. 176.812 Section 176.812... TONS) INSPECTION AND CERTIFICATION Material Inspections § 176.812 Pressure vessels and boilers. (a.... (b) Periodic inspection and testing requirements for boilers are contained in § 61.05 in subchapter F...

  11. 46 CFR 115.812 - Pressure vessels and boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Pressure vessels and boilers. 115.812 Section 115.812... CERTIFICATION Material Inspections § 115.812 Pressure vessels and boilers. (a) Pressure vessels must be tested... testing requirements for boilers are contained in § 61.05 in subchapter F of this chapter. [CGD 85-080, 61...

  12. 46 CFR 109.205 - Inspection of boilers and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Inspection of boilers and machinery. 109.205 Section 109... OPERATIONS Tests, Drills, and Inspections § 109.205 Inspection of boilers and machinery. The chief engineer or engineer in charge, before he assumes charge of the boilers and machinery of a unit shall inspect...

  13. 40 CFR 63.988 - Incinerators, boilers, and process heaters.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Incinerators, boilers, and process... Routing to a Fuel Gas System or a Process § 63.988 Incinerators, boilers, and process heaters. (a) Equipment and operating requirements. (1) Owners or operators using incinerators, boilers, or process...

  14. Aspects of new material application for boilers construction

    International Nuclear Information System (INIS)

    Czerniawski, R.

    1996-01-01

    Review of steel types commonly used for energetic boilers construction has been done. The worldwide trends in new materials application for improvement of boilers quality have been discussed. The mechanical properties of boiler construction steels have been shown and compared. 3 refs, 5 figs, 1 tab

  15. Lower price for solar boilers must improve market penetration

    International Nuclear Information System (INIS)

    Koevoet, J.B.J.

    1999-01-01

    The Dutch government aims at 1.7 PJ thermal energy for the year 2007 to be supplied by solar water heaters. For that target the number of installed solar boilers must increase seven times the number of installed solar boilers in 1998. This can be stimulated by a considerable reduction of the market price for such boilers

  16. 10 CFR 431.82 - Definitions concerning commercial packaged boilers.

    Science.gov (United States)

    2010-01-01

    ... gases. Manufacturer of a commercial packaged boiler means any person who manufactures, produces... 10 Energy 3 2010-01-01 2010-01-01 false Definitions concerning commercial packaged boilers. 431.82... COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Packaged Boilers § 431.82 Definitions concerning commercial...

  17. 40 CFR 761.71 - High efficiency boilers.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false High efficiency boilers. 761.71... PROHIBITIONS Storage and Disposal § 761.71 High efficiency boilers. (a) To burn mineral oil dielectric fluid containing a PCB concentration of ≥50 ppm, but boiler shall comply with the following...

  18. 49 CFR 230.36 - Hydrostatic testing of boilers.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Hydrostatic testing of boilers. 230.36 Section 230... Appurtenances Pressure Testing of Boilers § 230.36 Hydrostatic testing of boilers. (a) Time of test. The... to any hydrostatic pressure. Hydrostatic testing required by these rules shall be conducted at 25...

  19. Frictional pressure drop of high pressure steam-water two-phase flow in internally helical ribbed tubes

    International Nuclear Information System (INIS)

    Tingkuan, C.; Xuanzheng, C.

    1987-01-01

    It is well known that the internally helical ribbed tubes are effective in suppressing the dry-out in boiling tubes at high pressures, so they are widely used as furnace water wall tubes in modern large steam power boilers. Design of the boilers requires the data on frictional pressure drop characteristics of the ribbed tubes, but they are not sufficient now. This paper describes the experimental results on the adiabatic frictional pressure drop in both horizontal ribbed tubes with measured mean inside diameter of 11.69 mm and 35.42 mm at high pressure from 10 to 21 MPa, mass flow rate from 350 to 3800 kg/m/sup 2/s and steam quality from 0 to 1 in our high pressure electrically heated water loop. Simultaneously, both smooth tubes under the same conditions for comparison. Based on the tests the correlation for determining the frictional pressure drop of internally ribbed tubes are proposed

  20. Optimization of Boiler Heat Load in Water-Heating Boiler-House

    Directory of Open Access Journals (Sweden)

    B. A. Bayrashevsky

    2009-01-01

    Full Text Available An analytical method for optimization of water-heating boiler loads has been developed on the basis of approximated semi-empirical dependences pertaining to changes of boiler gross efficiency due to its load. A complex (∂tух/∂ξΔξ is determined on the basis of a systematic analysis (monitoring of experimental data and the Y. P. Pecker’s formula for calculation of balance losses q2. This complex makes it possible to set a corresponding correction to a standard value of the boiler gross efficiency due to contamination of heating surfaces.Software means for optimization of water-heating boilers has been developed and it is recommended to be applied under operational conditions.

  1. Steam generator tube extraction

    International Nuclear Information System (INIS)

    Delorme, H.

    1985-05-01

    To enable tube examination on steam generators in service, Framatome has now developed a process for removing sections of steam generator tubes. Tube sections can be removed without being damaged for treating the tube section expanded in the tube sheet

  2. Boiler and steam generator corrosion: Nuclear power plants. (Latest citations from the NTIS Bibliographic database). Published Search

    International Nuclear Information System (INIS)

    1993-09-01

    The bibliography contains citations concerning corrosion effects, mechanisms, detection, and inhibition in nuclear powered steam generators. Pitting, stress corrosion cracking, and crevice corrosion studies performed on the water side and hot gas side of the heat exchanger tubes and support structures are presented. Water treatment, corrosion monitoring, chemical cleaning, and descaling methods are considered. Fossil fuel fired boilers are examined in a separate bibliography. (Contains a minimum of 138 citations and includes a subject term index and title list.)

  3. Selecting Actuator Configuration for a Benson Boiler

    DEFF Research Database (Denmark)

    Kragelund, Martin Nygaard; Leth, John-Josef; Wisniewski, Rafal

    2009-01-01

    with particular focus on a boiler in a power plant operated by DONG Energy - a Danish energy supplier. The problem has been reformulated using mathematic notions from economics. The selection of actuator configuration has been limited to the fuel system which in the considered plant consists of three different...

  4. Environmental control during steam boiler washing

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Marcio A.B.; Abreu Pereira, Vera L. de [Companhia Petroquimica do Nordeste (COPENE), Camacari, BA (Brazil). Div. de Engenharia Ambiental; Ringler, Ulrich E.S. [PROMON Engenharia Ltda., Salvador, BA (Brazil)

    1993-12-31

    The washing and chemical cleaning of boilers, activities of a high polluting potential, are responsible for the generation of wastewater of high contents of heavy metals, suspended solids and chemical oxygen demand (COD). This paper describes the actions carried out by COPENE - Petroquimica do Nordeste S/A - in order to reduce this problem. (author). 10 refs., 3 figs., 2 tabs.

  5. The investigation of the locomotive boiler material

    International Nuclear Information System (INIS)

    Tucholski, Z.; Wasiak, J.; Bilous, W.; Hajewska, E.

    2006-01-01

    In the paper, the history of narrow-gauge railway system is described. The other information about the steam locomotive construction, as well as the technical regulations of its construction and exploitation are also done. The results of the studies of the locomotive boiler material are presented. (authors)

  6. Coal reburning technology for cyclone boilers

    International Nuclear Information System (INIS)

    Yagiela, A.S.; Maringo, G.J.; Newell, R.J.; Farzan, H.

    1990-01-01

    Babcock and Wilcox has obtained encouraging results from engineering feasibility and pilot-scale proof-of-concept studies of coal reburning for cyclone boiler NO x control. Accordingly, B and W completed negotiations for a clean coal cooperative agreement with the Department of Energy to demonstrate coal reburning technology for cyclone boilers. The host site for the demonstration is the Wisconsin Power and Light (WP and L) Company's 100MWe Nelson Dewey Station. Reburning involves the injection of a supplemental fuel (natural gas, oil, or coal) into the main furnace to produce locally reducing stoichiometric conditions which convert the NO x produced therein to molecular nitrogen, thereby reducing overall NO x emissions. There are currently no commercially-demonstrated combustion modification techniques for cyclone boilers which reduce NO x emissions. The emerging reburning technology offers cyclone boiler operators a promising alternative to expensive flue gas cleanup techniques for NO x emission reduction. This paper reviews baseline testing results at the Nelson Dewey Station and pilot-scale results simulating Nelson Dewey operation using pulverized coal (PC) as the reburning fuel. Outcomes of the model studies as well as the full-scale demonstration preliminary design are discussed

  7. Environmental control during steam boiler washing

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Marcio A.B.; Abreu Pereira, Vera L. de [Companhia Petroquimica do Nordeste (COPENE), Camacari, BA (Brazil). Div. de Engenharia Ambiental; Ringler, Ulrich E.S. [PROMON Engenharia Ltda., Salvador, BA (Brazil)

    1994-12-31

    The washing and chemical cleaning of boilers, activities of a high polluting potential, are responsible for the generation of wastewater of high contents of heavy metals, suspended solids and chemical oxygen demand (COD). This paper describes the actions carried out by COPENE - Petroquimica do Nordeste S/A - in order to reduce this problem. (author). 10 refs., 3 figs., 2 tabs.

  8. High temperature corrosion investigations at AW2-bio. Final report; Biomass boiler

    Energy Technology Data Exchange (ETDEWEB)

    Borg, U.

    2011-01-15

    The measured corrosion rates in the test superheaters and ordinary superheaters of Avedoere 2 biomass boiler reveal that the corrosion rate increases with metal temperature and is significantly accelerated above steam temperatures of 540 deg. C. For the boiler with a live steam temperature of 540 deg. C, the measured corrosion rates in superheater 2 and 3 were up to 1mm pr. 10000 hours. It was observed that the flue gas temperature and heat flux had a significant effect on the corrosion rates through the surface metal temperature. Thus, the highest corrosion rates in the ordinary superheaters were not found at the position of the highest steam temperature in the outlet of superheater 3, but at the outlet of superheater 2. A steam temperature of approximately 580 deg. C at the outlet of one of the test superheater loops caused a tube fracture after a few months. A HVOF coating was applied to a section of superheater 2 and at a higher temperature in the test superheater loop. Analyses of the tube section after exposure showed that parts of the coating were not present and corrosion of the underlying TP347H FG was apparent. This indicates that the coating had spalled during operation. Furthermore, chlorine diffusion through the coating was observed causing attack at the coating-alloy interface. The project work has shown that it is not possible to increase the live steam temperature of the biomass fired boiler to more than 540 deg. C without a significant increase in superheater corrosion rates for the applied tube materials and coatings. (Author)

  9. The behavior of ash species in suspension fired biomass boilers

    DEFF Research Database (Denmark)

    Jensen, Peter Arendt

    While fluid bed and grate fired boilers initially was the choice of boilers used for power production from both wood and herbaceous biomass, in recent years suspension fired boilers have been increasingly used for biomass based power production. In Denmark several large pulverized fuel boilers have...... been converted from coal to biomass combustion in the last 15 years. This have included co-firing of coal and straw, up to 100% firing of wood or straw andthe use of coal ash as an additive to remedy problems with wood firing. In parallel to the commercialization of the pulverized biomass firing...... technology a long range of research studies have been conducted, to improve our understanding of the influence and behavior of biomass ash species in suspension fired boilers. The fuel ash plays a key role with respect tooptimal boiler operation and influences phenomena’s as boiler chamber deposit formation...

  10. Ear Tubes

    Science.gov (United States)

    ... of the ear drum or eustachian tube, Down Syndrome, cleft palate, and barotrauma (injury to the middle ear caused by a reduction of air pressure, ... specialist) may be warranted if you or your child has experienced repeated ... fluid in the middle ear, barotrauma, or have an anatomic abnormality that ...

  11. Computation Modeling and Assessment of Nanocoatings for Ultra Supercritical Boilers

    Energy Technology Data Exchange (ETDEWEB)

    J. Shingledecker; D. Gandy; N. Cheruvu; R. Wei; K. Chan

    2011-06-21

    Forced outages and boiler unavailability of coal-fired fossil plants is most often caused by fire-side corrosion of boiler waterwalls and tubing. Reliable coatings are required for Ultrasupercritical (USC) application to mitigate corrosion since these boilers will operate at a much higher temperatures and pressures than in supercritical (565 C {at} 24 MPa) boilers. Computational modeling efforts have been undertaken to design and assess potential Fe-Cr-Ni-Al systems to produce stable nanocrystalline coatings that form a protective, continuous scale of either Al{sub 2}O{sub 3} or Cr{sub 2}O{sub 3}. The computational modeling results identified a new series of Fe-25Cr-40Ni with or without 10 wt.% Al nanocrystalline coatings that maintain long-term stability by forming a diffusion barrier layer at the coating/substrate interface. The computational modeling predictions of microstructure, formation of continuous Al{sub 2}O{sub 3} scale, inward Al diffusion, grain growth, and sintering behavior were validated with experimental results. Advanced coatings, such as MCrAl (where M is Fe, Ni, or Co) nanocrystalline coatings, have been processed using different magnetron sputtering deposition techniques. Several coating trials were performed and among the processing methods evaluated, the DC pulsed magnetron sputtering technique produced the best quality coating with a minimum number of shallow defects and the results of multiple deposition trials showed that the process is repeatable. scale, inward Al diffusion, grain growth, and sintering behavior were validated with experimental results. The cyclic oxidation test results revealed that the nanocrystalline coatings offer better oxidation resistance, in terms of weight loss, localized oxidation, and formation of mixed oxides in the Al{sub 2}O{sub 3} scale, than widely used MCrAlY coatings. However, the ultra-fine grain structure in these coatings, consistent with the computational model predictions, resulted in accelerated Al

  12. Medium pressure boiler water chemistry optimization using neutralizing amines mixture reagent AMINAT™ PK-2 at CEPP “Borovichi Refractories Plant” of JSC “BKO”

    Science.gov (United States)

    Guseva, O. V.; Butakova, M. V.; Orlov, K. A.; Vinogradov, S. V.; Pavlenko, L. S.

    2017-11-01

    An overview of the neutralizing amine based reagent AMINAT PK-2 usage for water chemistry of steam boilers for medium pressure boiler was given. Long term experiment showed that new reagent allows to decrease corrosion rate comparing with old water chemistry based on ammonia only. Two dosage schemes in different cycle places discussed. Scheme with two points on injection showed better results. Results of corrosion rates experiments and photos of tubes inner surfaces are presented. Based on fuel savings due to reducing scale formation the total annual economy for last year was 5.1 million Russian roubles.

  13. Operational control and maintenance integrity of typical and atypical coil tube steam generating systems

    Energy Technology Data Exchange (ETDEWEB)

    Beardwood, E.S.

    1999-07-01

    Coil tube steam generators are low water volume to boiler horsepower (bhp) rating, rapid steaming units which occupy substantially less space per boiler horsepower than equivalent conventional tire tube and water tube boilers. These units can be retrofitted into existing steam systems with relative ease and are more efficient than the generators they replace. During the early 1970's they became a popular choice for steam generation in commercial, institutional and light to medium industrial applications. Although these boiler designs do not require skilled or certified operators, an appreciation for a number of the operational conditions that result in lower unscheduled maintenance, increased reliability and availability cycles would be beneficial to facility owners, managers, and operators. Conditions which afford lower operating and maintenance costs will be discussed from a practical point of view. An overview of boiler design and operation is also included. Pitfalls are provided for operational and idle conditions. Water treatment application, as well as steam system operations not conducive to maintaining long term system integrity; with resolutions, will be addressed.

  14. Maximising safety in the boiler house.

    Science.gov (United States)

    Derry, Carr

    2013-03-01

    Last month's HEJ featured an article, the second in our new series of guidance pieces aimed principally at Technician-level engineers, highlighting some of the key steps that boiler operators can take to maximise system performance and efficiency, and thus reduce running both costs and carbon footprint. In the third such article, Derry Carr, C.Env, I.Eng, BSc (Hons), M.I.Plant.E., M.S.O.E., technical manager & group gas manager at Dalkia, who is vice-chairman of the Combustion Engineering Association, examines the key regulatory and safety obligations for hospital energy managers and boiler technicians, a number of which have seen changes in recent years with revision to guidance and other documentation.

  15. Recovery boiler model; Soodakattilan kehitystyoe III

    Energy Technology Data Exchange (ETDEWEB)

    Janka, K.; Ylitalo, M.; Sundstroem, K.; Helke, R.; Heinola, M. [Kvaerner Pulping Oy, Tampere (Finland)

    1997-10-01

    The recovery boiler model was further tested and developed. At this moment the model includes submodels for: droplet drying, pyrolysis, char burning, gas burning and for droplet trajectory. During 1996 the formation of CH{sub 4} during pyrolysis and release of sulfur was included to the model. Further the formation of NO from fuel nitrogen and formation of thermal- NO were included to the model using Arrhenius type reaction rate equations. The calculated results are realistic and the model is used as a tool to find out methods to increase the efficiency and availability and decrease the emissions. Analysing the results of the earlier field study of 8 boilers showed that the furnace heat load, fuming rate, find the black liquor composition have influence on the enrichment of the potassium to the fly ash. (orig.)

  16. Biomass Cofiring in Coal-Fired Boilers

    Energy Technology Data Exchange (ETDEWEB)

    2004-06-01

    Cofiring biomass-for example, forestry residues such as wood chips-with coal in existing boilers is one of the easiest biomass technologies to implement in a federal facility. The current practice is to substitute biomass for up to 20% of the coal in the boiler. Cofiring has many benefits: it helps to reduce fuel costs as well as the use of landfills, and it curbs emissions of sulfur oxide, nitrogen oxide, and the greenhouse gases associated with burning fossil fuels. This Federal Technology Alert was prepared by the Department of Energy's Federal Energy Management Program to give federal facility managers the information they need to decide whether they should pursue biomass cofiring at their facilities.

  17. Stationary Engineers Apprenticeship. Related Training Modules. 12.1-12.9. Boilers.

    Science.gov (United States)

    Lane Community Coll., Eugene, OR.

    This learning module, one in a series of 20 related training modules for apprentice stationary engineers, deals with boilers. Addressed in the individual instructional packages included in the module are the following topics: firetube and watertube boilers; boiler construction; procedures for operating and cleaning boilers; and boiler fittings,…

  18. 46 CFR 52.25-7 - Electric boilers (modifies PEB-1 through PEB-19).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Electric boilers (modifies PEB-1 through PEB-19). 52.25... ENGINEERING POWER BOILERS Other Boiler Types § 52.25-7 Electric boilers (modifies PEB-1 through PEB-19). Electric boilers required to comply with this part must meet the applicable provisions in this part and the...

  19. Circulating fluidized bed boilers design and operations

    CERN Document Server

    Basu, Prabir

    1991-01-01

    This book provides practicing engineers and students with insight into the design and operation of circulating fluidized bed (CFB) boilers. Through a combination of theoretical concepts and practical experience, this book gives the reader a basic understanding of the many aspects of this subject.Important environmental considerations, including solid waste disposal and predicted emissions, are addressed individually in separate chapters. This book places an emphasis on combustion, hydrodynamics, heat transfer, and material issues, and illustrates these concepts with numerous examples of pres

  20. Chromate dermatitis from a boiler lining.

    Science.gov (United States)

    Rycroft, R J; Calnan, C D

    1977-08-01

    Chromate dermatitis is described in a mechanical fitter working inside boiler combustion chambers. A source of hexavalent chromate is traced to the action of the heat and alkaline fuel ash on trivalent chrome ore in parts of the refractory lining. Removal of the patient from this contact has resulted in almost complete clearing of his dermatitis, without any relapse, during a 9-month follow-up period.

  1. Husk energy for boilers and furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Deven, M.

    1985-10-01

    In view of the technical feasibility and economic viability, industries located in rice, coconut, and cotton growing areas, can easily switch over from oil/coal fired furnace/boilers to husk fired ones and thereby effect fuel economy. The banks and financial institutions will readily agree to provide finance as per directions of the governments and in some cases they also offer subsidy for development and utilization of energy saving devices.

  2. Evaluation of internal boiler components and gases using a high-temperature infrared (IR) lens

    Science.gov (United States)

    Hammaker, Robert G.; Colsher, Richard J.; Miles, Jonathan J.; Madding, Robert P.

    1996-03-01

    Fuel accounts for an average of seventy percent of the yearly operational and maintenance costs of all the fossil stations in the United States. This amounts to 30 billion dollars spent for fuel each year. In addition, federal and state environmental codes have been enforcing stricter regulations that demand cleaner environments, such as the reduction of nitrogen oxides (NOx), which are a by-product of the fossil fuel flame. If the burn of the flame inside a boiler could be optimized, the usage of fuel and the amounts of pollution produced would be significantly reduced, and many of the common boiler tube failures can be avoided. This would result in a major dollar savings to the utility industry, and would provide a cleaner environment. Accomplishing these goals will require a major effort from the designers and operators that manufacture, operate, and maintain the fossil stations. Over the past few years re-designed burners have been installed in many boilers to help control the temperatures and shape of the flame for better performance and NOx reduction. However, the measurement of the processes and components inside the furnace, that could assist in determining the desired conditions, can at times be very difficult due to the hostile hot environment. In an attempt to resolve these problems, the EPRI M&D Center and a core group of EPRI member utilities have undertaken a two-year project with various optical manufacturers, IR manufacturers, and IR specialists, to fully develop an optical lens that will withstand the high furnace temperatures. The purpose of the lens is to explore the possibilities of making accurate high temperature measurements of the furnace processes and components in an ever-changing harsh environment. This paper provides an introduction to EPRI's internal boiler investigation using an IR high temperature lens (HTL). The paper describes the objectives, approach, benefits, and project progress.

  3. Electron tube

    Science.gov (United States)

    Suyama, Motohiro [Hamamatsu, JP; Fukasawa, Atsuhito [Hamamatsu, JP; Arisaka, Katsushi [Los Angeles, CA; Wang, Hanguo [North Hills, CA

    2011-12-20

    An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

  4. Particulate emission abatement for Krakow boiler houses

    Energy Technology Data Exchange (ETDEWEB)

    Wysk, R.

    1995-12-31

    Among the many strategies for improving air quality in Krakow, one possible method is to adapt new and improved emission control technology. This project focuses on such a strategy. In order to reduce dust emissions from coal-fueled boilers, a new device called a Core Separator has been introduced in several boiler house applications. This advanced technology has been successfully demonstrated in Poland and several commercial units are now in operation. Particulate emissions from the Core Separator are typically 3 to 5 times lower than those from the best cyclone collectors. It can easily meet the new standard for dust emissions which will be in effect in Poland after 1997. The Core Separator is a completely inertial collector and is based on a unique recirculation method. It can effectively remove dust particles below 10 microns in diameter, the so-called PM-10 emissions. Its performance approaches that of fabric filters, but without the attendant cost and maintenance. It is well-suited to the industrial size boilers located in Krakow. Core Separators are now being marketed and sold by EcoInstal, one of the leading environmental firms in Poland, through a cooperative agreement with LSR Technologies.

  5. Boiler systems for nuclear powered reactors

    International Nuclear Information System (INIS)

    Cook, R.K.; George, B.V.

    1979-01-01

    A power generating plant which comprises a heat source, at least one main steam turbine and at least one main boiler heated by heat from the heat source and providing the steam to drive the turbine, comprises additionally at least one further steam turbine, smaller than the main turbine, and at least one further boiler, of lower capacity than the main boiler, and heated from the same heat source and providing steam for the further turbine. Particularly advantageous in nuclear power stations, where the heat source is a nuclear reactor, the invention enables peak loads, above the normal continuous rating of the main generators driven by the main turbines, to be met by the further turbine(s) and one or more further generators driven thereby. This enables the main turbines to be freed from the thermal stresses of rapid load changes, which stresses are more easily accommodated by the smaller and thus more tolerant further turbine(s). Thus auxiliary diesel-driven or other independent power plant may be made partly or wholly unnecessary. Further, low-load running which would be inefficient if achieved by means of the main turbine(s), can be more efficiently effected by shutting them down and using the smaller further turbine(s) instead. These latter may also be used to provide independent power for servicing the generating plant during normal operation or during emergency or other shutdown, and in this latter case may also serve as a heat sink for the shutdown reactor

  6. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman; R.W. Swindeman; J. Sarver; J. Blough; W. Mohn; M. Borden; S. Goodstine; I. Perrin

    2003-10-20

    The principal objective of this project is to develop materials technology for use in ultrasupercritical (USC) plant boilers capable of operating with 760 C (1400 F), 35 MPa (5000 psi) steam. This project has established a government/industry consortium to undertake a five-year effort to evaluate and develop of advanced materials that allow the use of advanced steam cycles in coal-based power plants. These advanced cycles, with steam temperatures up to 760 C, will increase the efficiency of coal-fired boilers from an average of 35% efficiency (current domestic fleet) to 47% (HHV). This efficiency increase will enable coal-fired power plants to generate electricity at competitive rates (irrespective of fuel costs) while reducing CO{sub 2} and other fuel-related emissions by as much as 29%. Success in achieving these objectives will support a number of broader goals. First, from a national prospective, the program will identify advanced materials that will make it possible to maintain a cost-competitive, environmentally acceptable coal-based electric generation option. High sulfur coals will specifically benefit in this respect by having these advanced materials evaluated in high-sulfur coal firing conditions and from the significant reductions in waste generation inherent in the increased operational efficiency. Second, from a national prospective, the results of this program will enable domestic boiler manufacturers to successfully compete in world markets for building high-efficiency coal-fired power plants.

  7. Low Cost Polymer heat Exchangers for Condensing Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Butcher, Thomas [Brookhaven National Lab. (BNL), Upton, NY (United States); Trojanowski, Rebecca [Brookhaven National Lab. (BNL), Upton, NY (United States); Wei, George [Brookhaven National Lab. (BNL), Upton, NY (United States); Worek, Michael [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-09-30

    Work in this project sought to develop a suitable design for a low cost, corrosion resistant heat exchanger as part of a high efficiency condensing boiler. Based upon the design parameters and cost analysis several geometries and material options were explored. The project also quantified and demonstrated the durability of the selected polymer/filler composite under expected operating conditions. The core material idea included a polymer matrix with fillers for thermal conductivity improvement. While the work focused on conventional heating oil, this concept could also be applicable to natural gas, low sulfur heating oil, and biodiesel- although these are considered to be less challenging environments. An extruded polymer composite heat exchanger was designed, built, and tested during this project, demonstrating technical feasibility of this corrosion-resistant material approach. In such flue gas-to-air heat exchangers, the controlling resistance to heat transfer is in the gas-side convective layer and not in the tube material. For this reason, the lower thermal conductivity polymer composite heat exchanger can achieve overall heat transfer performance comparable to a metal heat exchanger. However, with the polymer composite, the surface temperature on the gas side will be higher, leading to a lower water vapor condensation rate.

  8. High temperature oxidation in boiler environment of chromized steel

    Science.gov (United States)

    Alia, F. F.; Kurniawan, T.; Asmara, Y. P.; Ani, M. H. B.; Nandiyanto, A. B. D.

    2017-10-01

    The demand for increasing efficiency has led to the development and construction of higher operating temperature power plant. This condition may lead to more severe thickness losses in boiler tubes due to excessive corrosion process. Hence, the research to improve the corrosion resistance of the current operated material is needed so that it can be applied for higher temperature application. In this research, the effect of chromizing process on the oxidation behaviour of T91 steel was investigated under steam condition. In order to deposit chromium, mixture of chromium (Cr) powder as master alloy, halide salt (NH4Cl) powder as activator and alumina (Al2O3) powder as inert filler were inserted into alumina retort together with the steel sample and heated inside furnace at 1050°C for ten hours under argon gas environment. Furthermore, for the oxidation process, steels were exposed at 700°C at different oxidation time (6h-24h) under steam condition. From FESEM/EDX analysis, it was found that oxidation rate of pack cemented steel was lower than the un-packed steel. These results show that Cr from chromizing process was able to become reservoir for the formation of Cr2O3 in high temperature steam oxidation, and its existence can be used for a longer oxidation time.

  9. Field Test of Boiler Primary Loop Temperature Controller

    Energy Technology Data Exchange (ETDEWEB)

    Glanville, P. [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States); Rowley, P. [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States); Schroeder, D. [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States); Brand, L. [Partnership for Advanced Residential Retrofit, Des Plaines, IL (United States)

    2014-09-01

    Beyond these initial system efficiency upgrades are an emerging class of Advanced Load Monitoring (ALM) aftermarket controllers that dynamically respond to the boiler load, with claims of 10% to 30% of fuel savings over a heating season. For hydronic boilers specifically, these devices perform load monitoring, with continuous measurement of supply and, in some cases, return water temperatures. Energy savings from these ALM controllers are derived from dynamic management of the boiler differential, where a microprocessor with memory of past boiler cycles prevents the boiler from firing for a period of time, to limit cycling losses and inefficient operation during perceived low load conditions. These differ from OTR controllers, which vary boiler setpoint temperatures with ambient conditions while maintaining a fixed differential.

  10. Modelling, simulating and optimizing boiler heating surfaces and evaporator circuits

    DEFF Research Database (Denmark)

    Sørensen, K.; Condra, T.; Houbak, Niels

    2003-01-01

    A model for optimizing the dynamic performance of boiler have been developed. Design variables related to the size of the boiler and its dynamic performance have been defined. The object function to be optimized takes the weight of the boiler and its dynamic capability into account. As constraints...... for the optimization a dynamic model for the boiler is applied. Furthermore a function for the value of the dynamic performance is included in the model. The dynamic models for simulating boiler performance consists of a model for the flue gas side, a model for the evaporator circuit and a model for the drum....... The dynamic model has been developed for the purpose of determining boiler material temperatures and heat transfer from the flue gas side to the water-/steam side in order to simulate the circulation in the evaporator circuit and hereby the water level fluctuations in the drum. The dynamic model has been...

  11. Behavioral study solar boilers 1994. Summary. Part 2 (households)

    International Nuclear Information System (INIS)

    Visser, J.M.

    1995-04-01

    The aim of the Dutch national solar boiler campaign of NOVEM and Holland Solar is to realize the installation of 300,000 solar boilers in the Netherlands in the year 2010. In 1995 10,000 boilers were installed. More knowledge of the decision making process and the backgrounds and motives of (potential) buyers is required. From September 1994 to March 1995 a survey has been carried out of the decision making processes in households and housing corporations. The most important results, conclusions and recommendations of the survey are summarized in this report. The parameters that can influence the decision whether to purchase a solar boiler or not are knowledge about the solar boiler, the attitude towards the solar boiler and towards the use of energy and the environment, risk perception, social aspects, information retrieval behavior, constraints, and socio-economic aspects. 44 tabs

  12. NOx PREDICTION FOR FBC BOILERS USING EMPIRICAL MODELS

    Directory of Open Access Journals (Sweden)

    Jiří Štefanica

    2014-02-01

    Full Text Available Reliable prediction of NOx emissions can provide useful information for boiler design and fuel selection. Recently used kinetic prediction models for FBC boilers are overly complex and require large computing capacity. Even so, there are many uncertainties in the case of FBC boilers. An empirical modeling approach for NOx prediction has been used exclusively for PCC boilers. No reference is available for modifying this method for FBC conditions. This paper presents possible advantages of empirical modeling based prediction of NOx emissions for FBC boilers, together with a discussion of its limitations. Empirical models are reviewed, and are applied to operation data from FBC boilers used for combusting Czech lignite coal or coal-biomass mixtures. Modifications to the model are proposed in accordance with theoretical knowledge and prediction accuracy.

  13. Chest tube insertion

    Science.gov (United States)

    Chest drainage tube insertion; Insertion of tube into chest; Tube thoracostomy; Pericardial drain ... Be careful there are no kinks in your tube. The drainage system should always sit upright and be placed ...

  14. Release of Corrosive Species above the Grate in a Waste Boiler and the Implication for Improved Electrical Efficiency

    DEFF Research Database (Denmark)

    Bøjer, Martin; Jensen, Peter Arendt; Dam-Johansen, Kim

    2010-01-01

    A relatively low electrical efficiency of 20−25% is obtained in typical west European waste boilers. Ash species released from the grate combustion zone form boiler deposits with high concentrations of Cl, Na, K, Zn, Pb, and S that cause corrosion of superheater tubes at high temperature....... The superheater steam temperature has to be limited to around 425 °C, and thereby, the electrical efficiency remains low compared to wood or coal-fired boilers. If a separate part of the flue gas from the grate has a low content of corrosive species, it may be used to superheat steam to a higher temperature......, and thereby, the electrical efficiency of the plant can be increased. In this study, the local temperature, the gas concentrations of CO, CO2, and O2, and the release of the volatile elements Cl, S, Na, K, Pb, Zn, Cu, and Sn were measured above the grate in a waste boiler to investigate if a selected fraction...

  15. Degradation of superheater tubes made of austenitic T321H steel after long term service

    Energy Technology Data Exchange (ETDEWEB)

    Hernas, Adam [Silesian Technical Univ., Katowice (Poland). Faculty of Material Science; Augustyniak, Boleslaw; Chmielewski, Marek [Gdansk Univ. of Technology (Poland). Mechanical Dept.; Sablik, M.J. [Applied Magnetic and Physical Modeling, LLC, San Antonio, TX (United States)

    2010-07-01

    There are presented results of complementary tests performed for the evaluation of creep damage in austenitic steel grade T321H exploited over 200,000 hours in the secondary superheater part of a power plant boiler. The following techniques have been applied: SEM microscopy, X-ray diffraction, tensile tests, hardness measurements and novel eddy current inspection. The novel eddy current inspection is proposed as a non-destructive method of estimating the creep damage stage of austenite steel boiler tubes after long-term service in power plants. We compare the results provided by the different techniques and discuss the correlations and also point out the problems which need to be addressed in order to elaborate the remaining life assessment of austenitic boiler tubes. (orig.)

  16. Radiological investigation in the boiler's maintenance operations in a Coal-Fired power plant

    International Nuclear Information System (INIS)

    Robles, Beatriz; Mora, Juan C.; Cancio, David; Baeza, Antonio; Corbacho, Jose A.

    2008-01-01

    As part of a study being performed in the four biggest coal-fired power plants in Spain, the formation of scales of radioisotopes in parts of the heat recovery system was investigated. This effect should be more important in the case of 210 Po and 210 Pb. Thereby, it is likely in given specific chemical conditions that scales could be formed with a high concentration of 210 Pb, probably in secular equilibrium with 210 Po and 210 Bi. Those scales could reach activity concentrations of some hundreds of Bq g -1 . In order to study within the boiler this scale formation, an investigation during the maintenance operations programmed in the 'Compostilla' coal-fired power plant (Ponferrada-Spain) was carried out. Those operations are performed each 2-3 years and last for around 30 or 40 days. Measurements of ambient dose equivalent (H * (10)) in the boiler before and after the entrance of the operators, together with beta surface contamination on the bottom ashes attached in the walls and on the tubes, were performed. The last measurements were carried out for screening purposes in order to select those areas on the tubes which could present Po scales. Even if chemical conditions are in general oxidising within the boiler, since conditions are not homogeneous, some zones were localized in which surface contamination was measured. In these spots, samples were collected and then measured in the laboratory. Moreover, an analysis of maintenance tasks, used personal protection equipment, working times and other important parameters was also carried out. This analysis is important in order to perform radiological evaluations, as realistic as possible, of the effective doses that could be received by maintenance operators. In the present study, the values of the measurements performed and the results of the assessment of the effective doses for the workers are presented. (author)

  17. Design, construction and operating experience of boilers at Wylfa power station

    Energy Technology Data Exchange (ETDEWEB)

    Razzell, R N [Wylfa Power Station, Central Electricity Generating Board, Gwynedd (United Kingdom)

    1988-07-01

    The report will describe the boilers, but will emphasise the problems encountered and the solutions. The boilers are 'once through' with start up drums. Some redundancy was provided but this advantage was lost due to downrating of gas temperature. The boilers are carbon steel suspended plattens (992 per reactor) tightly packed in the annular space between the core shielding and the spherical wall of the pressure vessel. This construction denies access to repair tube leaks. when a leak occurs the faulty platten has to be plugged off. This is done with the reactor at 60% power. The process will be described. Reactor 1 commenced operation in 1971, Reactor 2 in June 1971. Between 1972 and May 1984 21 leaks occurred which resulted in a major shutdown for investigation. This revealed the leaks were caused by gas flow induced vibration resulting in fretting of tubes in clips. Restraints and additional clamps were fitted. This has been successful but the modifications were extensive and in very difficult working conditions, the Reactor being shut down until May 1976. A family of leaks adjacent to personnel access ways commenced in Reactor 1 in 1975 which was later identified as erosion/corrosion on the water/steam side caused by the feed flow instability. This problem is common to both Reactors. Various modifications have been applied. Redistribution of feed flow using orifice plates and ferrules was only temporarily successful. Following extensive rig testing the feed water has been dosed with amino methyl proponal (AMP) since September 1983 with an immediate and sustained reduction in the leak rate. The amine provides protection through the steam/water phase. Rig testing continues to attain a better understanding of the erosion/corrosion. (author)

  18. Design, construction and operating experience of boilers at Wylfa power station

    International Nuclear Information System (INIS)

    Razzell, R.N.

    1988-01-01

    The report will describe the boilers, but will emphasise the problems encountered and the solutions. The boilers are 'once through' with start up drums. Some redundancy was provided but this advantage was lost due to downrating of gas temperature. The boilers are carbon steel suspended plattens (992 per reactor) tightly packed in the annular space between the core shielding and the spherical wall of the pressure vessel. This construction denies access to repair tube leaks. when a leak occurs the faulty platten has to be plugged off. This is done with the reactor at 60% power. The process will be described. Reactor 1 commenced operation in 1971, Reactor 2 in June 1971. Between 1972 and May 1984 21 leaks occurred which resulted in a major shutdown for investigation. This revealed the leaks were caused by gas flow induced vibration resulting in fretting of tubes in clips. Restraints and additional clamps were fitted. This has been successful but the modifications were extensive and in very difficult working conditions, the Reactor being shut down until May 1976. A family of leaks adjacent to personnel access ways commenced in Reactor 1 in 1975 which was later identified as erosion/corrosion on the water/steam side caused by the feed flow instability. This problem is common to both Reactors. Various modifications have been applied. Redistribution of feed flow using orifice plates and ferrules was only temporarily successful. Following extensive rig testing the feed water has been dosed with amino methyl proponal (AMP) since September 1983 with an immediate and sustained reduction in the leak rate. The amine provides protection through the steam/water phase. Rig testing continues to attain a better understanding of the erosion/corrosion. (author)

  19. Field Test of Boiler Primary Loop Temperature Controller

    Energy Technology Data Exchange (ETDEWEB)

    Glanville, P.; Rowley, P.; Schroeder, D.; Brand, L.

    2014-09-01

    Beyond these initial system efficiency upgrades are an emerging class of Advanced Load Monitoring (ALM) aftermarket controllers that dynamically respond to the boiler load, with claims of 10% to 30% of fuel savings over a heating season. For hydronic boilers specifically, these devices perform load monitoring, with continuous measurement of supply and in some cases return water temperatures. Energy savings from these ALM controllers are derived from dynamic management of the boiler differential, where a microprocessor with memory of past boiler cycles prevents the boiler from firing for a period of time, to limit cycling losses and inefficient operation during perceived low load conditions. These differ from OTR controllers, which vary boiler setpoint temperatures with ambient conditions while maintaining a fixed differential. PARR installed and monitored the performance of one type of ALM controller, the M2G from Greffen Systems, at multifamily sites in the city of Chicago and its suburb Cary, IL, both with existing OTR control. Results show that energy savings depend on the degree to which boilers are over-sized for their load, represented by cycling rates. Also savings vary over the heating season with cycling rates, with greater savings observed in shoulder months. Over the monitoring period, over-sized boilers at one site showed reductions in cycling and energy consumption in line with prior laboratory studies, while less over-sized boilers at another site showed muted savings.

  20. Between the boiler and buffer tank; Zwischen Kessel und Speicher

    Energy Technology Data Exchange (ETDEWEB)

    Ertmer, Katharina

    2013-08-06

    Some manufacturers offer new heating pump groups for return temperature raising for solid-fuel boilers. [German] Einige Hersteller bieten neue Heizungspumpengruppen zur Ruecklauftemperaturanhebung bei Festbrennstoffkesseln an.

  1. Simulation and testing of a new condensing boiler

    International Nuclear Information System (INIS)

    Rosa, L.; Tosato, R.

    1987-01-01

    The paper describes a new condensing boiler, characterized by the evacuation of flue-gases by natural draft. The best result is the consequent simplification of manufacturing, hook-up and operation of the boiler. Seasonal efficiency of the boiler, which operates with flue-gases conditioning to assure natural draft, rests about at same levels as for conventional condensing boilers. The authors emphasize the difficulty of simulate natural draft mechanism by mathematics because, in this case, flow of flue-gases and air at the draft diverter is strongly three-dimensional

  2. Premature failure of dissimilar metal weld joint at intermediate temperature superheater tube

    OpenAIRE

    Al Hajri, Mohammed; Malik, Anees U.; Meroufel, Abdelkader; Al-Muaili, Fahd

    2015-01-01

    Dissimilar metal weld (DMW) joint between alloyed steel (AS) and stainless steel (SS) failed at one of intermediate temperature superheater (ITSH) tube in steam/power generation plant boiler. The premature failure was detected after a relatively short time of operation (8 years) where the crack propagated circumferentially from AS side through the ITSH tube. Apart from physical examination, microstructural studies based on optical microscopy, SEM and EDX analysis were performed. The results o...

  3. This conveyor belt in a tube is a coal-heaver's dream

    Energy Technology Data Exchange (ETDEWEB)

    Gregorie, D

    1986-01-01

    This article describes a piece of equipment used for the handling of coal. Several of these tubulators have been installed in boiler houses in New Zealand. The tubulator is a conveyor belt in a tube and its details are presented. The innovative features of the conveyor are listed along with its advantages over existing systems.

  4. photomultiplier tubes

    CERN Multimedia

    photomultiplier tubes. A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

  5. photomultiplier tube

    CERN Multimedia

    photomultiplier tubes. A device to convert light into an electric signal (the name is often abbreviated to PM). Photomultipliers are used in all detectors based on scintillating material (i.e. based on large numbers of fibres which produce scintillation light at the passage of a charged particle). A photomultiplier consists of 3 main parts: firstly, a photocathode where photons are converted into electrons by the photoelectric effect; secondly, a multiplier chain consisting of a serie of dynodes which multiply the number of electron; finally, an anode, which collects the resulting current.

  6. Increase of energy efficiency in proportional adjusting of flow rate in the boiler circuit

    OpenAIRE

    Artamonov Pavel A.; Kurilenko Nikolai I.; Mamontov Gennady Ya.

    2017-01-01

    The article presents the results of theoretical studies in the field of the boiler circuit operating modes for the boiler rooms operating by the independent heat supply scheme. The 3D model of a boiler circuit for a boiler room with 3 MW rated output was developed, based on which there was made an estimation of the boiler pump performance indicators. There is proposed a method for reducing energy costs for the operation of the pumping equipment of the boiler circuit.

  7. Application of 1-hydroxyethylidene-1, 1-diphosphonic acid in boiler water for industrial boilers.

    Science.gov (United States)

    Zeng, Bin; Li, Mao-Dong; Zhu, Zhi-Ping; Zhao, Jun-Ming; Zhang, Hui

    2013-01-01

    The primary method used for boiler water treatment is the addition of chemicals to industrial boilers to prevent corrosion and scaling. The static scale inhibition method was used to evaluate the scale inhibition performance of 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP). Autoclave static experiments were used to study the corrosion inhibition properties of the main material for industrial boilers (20# carbon steel) with an HEDP additive in the industrial boiler water medium. The electrochemical behavior of HEDP on carbon steel corrosion control was investigated using electrochemical impedance spectroscopy and Tafel polarization techniques. Experimental results indicate that HEDP can have a good scale inhibition effect when added at a quantity of 5 to 7 mg/L at a test temperature of not more than 100 °C. To achieve a high scale inhibition rate, the HEDP dosage must be increased when the test temperature exceeds 100 °C. Electrochemical and autoclave static experimental results suggest that HEDP has a good corrosion inhibition effect on 20# carbon steel at a concentration of 25 mg/L. HEDP is an excellent water treatment agent.

  8. Deposit Probe Measurements in Large Biomass-Fired Grate Boilers and Pulverized-Fuel Boilers

    DEFF Research Database (Denmark)

    Hansen, Stine Broholm; Jensen, Peter Arendt; Jappe Frandsen, Flemming

    2014-01-01

    A number of full-scale deposit probe measuring campaigns conducted in grate-fired and suspension-fired boilers, fired with biomass, have been reviewed and compared. The influence of operational parameters on the chemistry of ash and deposits, on deposit build-up rates, and on shedding behavior has...... of the deposits formed is determined by the fly ash composition and the flue gas temperature; increases in the local flue gas temperature lead to higher contents of Si and Ca and lower contents of Cl in the deposits. The net deposit build-up rates in grate-fired and suspension-fired boilers are at similar levels....../wood-firing in suspension-fired boilers, shedding occurred by debonding with incomplete removal at flue gas temperatures of 600–1000 °C and by debonding with complete removal during wood-firing in suspension-fired boilers at high flue gas temperatures (1300 °C). Shedding events were not observed during wood suspension...

  9. Detailed investigation of Cl-corrosion initiated by deposits formed in biomass-fired boilers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, Flemming J.; Lith, S. van

    2009-10-15

    The aim was to investigate deposit-induced Cl-corrosion under well-controlled laboratory conditions, simulating the conditions in biomass-fired boilers. This has been done by exposing pieces of superheater tubes, covered by synthetic salts, at temperatures and gas mixtures simulating biomass-fired conditions. The corroded specimens have been studied in detail using a Scanning Electron Microscope (SEM), in order to determine the corrosion rate, and to investigate the chemistry and morphology of the corrosive attack. The project has been divided into four activities: A1: Relationship between the Cl-concentration in the deposit, and the corrosion rate. A2: Influence of cation type (K+ and Na+) on the mobility of Cl in the deposit. A3: Influence of metal temperature on the corrosion rate. A4: Critical evaluation of the existing experience for minimizing corrosion in full-scale boilers firing totally or partly with biomass. (LN)

  10. Boiler inspection manipulator for Torness Power Station

    International Nuclear Information System (INIS)

    Carrey, R.T.A.; Playle, M.J.

    1996-01-01

    In-service inspection at Torness Advanced Gas-cooled Reactor is achieved, via penetrations above and below the core area and boilers and through eight circulator penetrations for inspection of the sub-diagrid area. A manipulator is described which can access the area above the reactor core via any of these eight peripheral penetrations. The design and fabrication of the manipulator has led to innovation with a number of possible solutions being tendered. In reactor deployment of the successful design is expected in early 1997. (UK)

  11. Multiloop control of a drum boiler

    Directory of Open Access Journals (Sweden)

    Alena Kozáková

    2014-05-01

    Full Text Available The Equivalent Subsystems Method (ESM (Kozáková et al., 2011 is methodology of decentralized controller design in the frequency domain which allows designing local controllers using any SISO frequency domain method. The paper deals with the digital ESM version where digital local PID controllers guaranteeing required performance for the full system are designed for individual equivalent subsystems using the practice-oriented Sine-wave method (Bucz et al., 2012. The proposed decentralized controller design procedure was verified on the nonlinear benchmark drum boiler simulation model (Morilla, 2012.

  12. Nuclear reactors with auxiliary boiler circuit

    International Nuclear Information System (INIS)

    George, B.V.; Cook, R.K.

    1976-01-01

    A gas-cooled nuclear reactor has a main circulatory system for the gaseous coolant incorporating one or more main energy converting units, such as gas turbines, and an auxiliary circulatory system for the gaseous coolant incorporating at least one steam generating boiler arranged to be heated by the coolant after its passage through the reactor core to provide steam for driving an auxiliary steam turbine, such an arrangement providing a simplified start-up procedure also providing emergency duties associated with long term heat removal on reactor shut down

  13. A Study on Effect of Recirculated Exhaust Gas upon Performance and Exhaust Emissions in a Power Plant Boiler with FGR System

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Myung-whan; Jung, Kwong-ho; Park, Sung-bum [Gyeongsang Nat’l Univ., Jinju (Korea, Republic of)

    2016-04-15

    The effect of recirculated exhaust gas on performance and exhaust emissions with FGR rate are investigated by using a natural circulation, pressurized draft and water tube boiler with FGR system operating at several boiler loads and over fire air damper openings. The purpose of this study is to apply the FGR system to a power plant boiler for reducing NOx emissions. To activate the combustion, the OFA with 0 to 20% is supplied into the flame. When the suction damper of two stage combustion system installed in the upper side of wind box is opened by handling the lever between 0° and 90°, also, the combustion air supplied to burner is changed. It is found that the fuel consumption rate per evaporation rate did not show an obvious tendency to increase or decrease with rising the FGR rate, and NOx emissions at the same OFA damper opening are decreased, as FGR rates are elevated and boiler loads are dropped. While a trace amount of soot is emitted without regard to the operation conditions of boiler load, OFA damper opening and FGR rate, because soot emissions are eliminated by the electrostatic precipitator with a collecting efficiency of 86.7%.

  14. A Study on Effect of Recirculated Exhaust Gas upon Performance and Exhaust Emissions in a Power Plant Boiler with FGR System

    International Nuclear Information System (INIS)

    Bae, Myung-whan; Jung, Kwong-ho; Park, Sung-bum

    2016-01-01

    The effect of recirculated exhaust gas on performance and exhaust emissions with FGR rate are investigated by using a natural circulation, pressurized draft and water tube boiler with FGR system operating at several boiler loads and over fire air damper openings. The purpose of this study is to apply the FGR system to a power plant boiler for reducing NOx emissions. To activate the combustion, the OFA with 0 to 20% is supplied into the flame. When the suction damper of two stage combustion system installed in the upper side of wind box is opened by handling the lever between 0° and 90°, also, the combustion air supplied to burner is changed. It is found that the fuel consumption rate per evaporation rate did not show an obvious tendency to increase or decrease with rising the FGR rate, and NOx emissions at the same OFA damper opening are decreased, as FGR rates are elevated and boiler loads are dropped. While a trace amount of soot is emitted without regard to the operation conditions of boiler load, OFA damper opening and FGR rate, because soot emissions are eliminated by the electrostatic precipitator with a collecting efficiency of 86.7%.

  15. Equipment for inspection and carrying out repairs, if required, for tube bundles of steam raising units

    International Nuclear Information System (INIS)

    Gugel, G.

    1976-01-01

    The equipment solves the problem of being able to inspect and possibly to repair U-tubes of a vertical steam raising unit standing on a tube floor, without draining the primary medium and bringing the test equipment and tools into the inside of the boiler first. This is achieved by leaving a considerable part of the equipment permanently in the hemispherical space under the tube floor and operating it from the outside, on the other side of the concrete shielding. An inspection tube is threaded in turn horizontally through a concrete shield, a tube duct in the heat insulation of the steam raising unit, and through a hole in the hemispherical space under the tube floor into this space. The end of an angle tube can be moved axially from outside the concrete shield and can be rotated in a semicircle above the tube axis. By interposing a, for example, 12 part distributor with 12 short, differently bent tubes 12 adjacent tubes opening into the tube floor can be controlled and tested, by axial movement of the angle tube together with the distributor, e.g. 4 x 12 other U tubes. A turbulent flow sensor, for example, can be introduced through the angle tube and distributor. In the non-operational condition the equipment is moved into a recess via a supporting angle and stopped there. (ORU) [de

  16. Test of a small domestic boiler using different pellets

    International Nuclear Information System (INIS)

    Dias, J.; Costa, M.; Azevedo, J.L.T.

    2004-01-01

    This paper presents results from an experimental study performed on a 13 kW th commercial domestic boiler using pellets as fuel. Four different types of pellets were used and, for each one, the boiler was tested as a function of its capacity and the fan regulation affecting excess air. Measurements were performed for boiler heat load, pellet consumption rate, flue-gas temperature and composition. Mass balances allowed the calculation of the flue-gas flow rate and associated heat losses. Losses from incomplete combustion have also been quantified. Under boiler steady-state conditions the flue-gas O 2 concentration changes with boiler load and ventilation due to the regulation scheme of the boiler. Flue-gas CO shows a minimum for values of O 2 in the flue-gases of about 13%. NO x emissions are independent of excess air for low values of nitrogen in the fuel whereas, for larger values, NO x emissions increase with the O 2 present in the combustion products. The fractional conversion of the pellet nitrogen into NO x is in line with literature data. The boiler start-up was characterised by the temperature evolution inside and above the bed showing the propagation of combustion in the bed during about 10 min. During boiler start-up, a maximum in CO emissions was observed which is associated with the maximum combustion intensity, as typified by the flue-gas O 2 concentration and temperature, regardless the pellet type. (Author)

  17. 30 CFR 77.411 - Compressed air and boilers; general.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Compressed air and boilers; general. 77.411 Section 77.411 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... COAL MINES Safeguards for Mechanical Equipment § 77.411 Compressed air and boilers; general. All...

  18. Exergetic Modelling of Oil-Fired Steam Boilers | Ohijeagbon ...

    African Journals Online (AJOL)

    The performance variables and potential for energy savings in oil-fired industrial steam boilers were studied. Operational parameters of steam boilers using low pour fuel oil (LPFO) and diesel were used to determine thermodynamic properties of material streams and exergetic parameters. Analysis of thermodynamic ...

  19. Assessment of Some Performance Characteristics of Refuse Boiler ...

    African Journals Online (AJOL)

    A pioneer palm oil boiler unit, in an immense power self-contained oil mill, impaired by many years of accumulated depreciation, was rebuilt in the pattern of a design-out scheme aimed primarily at rehabilitating the entire boiler system to a state of functionality. The research work studied the pre-maintenance and post ...

  20. DESIGN REPORT: LOW-NOX BURNERS FOR PACKAGE BOILERS

    Science.gov (United States)

    The report describes a low-NOx burner design, presented for residual-oil-fired industrial boilers and boilers cofiring conventional fuels and nitrated hazardous wastes. The burner offers lower NOx emission levels for these applications than conventional commercial burners. The bu...

  1. Thermomechanical finite element analysis of hot water boiler structure

    Directory of Open Access Journals (Sweden)

    Živković Dragoljub S.

    2012-01-01

    Full Text Available The paper presents an application of the Finite Elements Method for stress and strain analysis of the hot water boiler structure. The aim of the research was to investigate the influence of the boiler scale on the thermal stresses and strains of the structure of hot water boilers. Results show that maximum thermal stresses appear in the zone of the pipe carrying wall of the first reversing chamber. This indicates that the most critical part of the boiler are weld spots of the smoke pipes and pipe carrying plate, which in the case of significant scale deposits can lead to cracks in the welds and water leakage from the boiler. The nonlinear effects were taken into account by defining the bilinear isotropic hardening model for all boiler elements. Temperature dependency was defined for all relevant material properties, i. e. isotropic coefficient of thermal expansion, Young’s modulus, and isotropic thermal conductivity. The verification of the FEA model was performed by comparing the measured deformations of the hot water boiler with the simulation results. As a reference object, a Viessmann - Vitomax 200 HW boiler was used, with the installed power of 18.2 MW. CAD modeling was done within the Autodesk Inventor, and stress and strain analysis was performed in the ANSYS Software.

  2. Water Boiler Change-Over in Mini-TPP Mode

    Directory of Open Access Journals (Sweden)

    B. A. Bayrashevsky

    2011-01-01

    Full Text Available The paper considers water boiler modernization by its change-over in mini-TPP mode with an expansion tank and a heating turbine of small capacity.  A software complex permitting to evaluate competitive ability of such water boiler modernization in comparison with a cogeneration plant.

  3. Hybrid system for fouling control in biomass boilers

    Energy Technology Data Exchange (ETDEWEB)

    Romeo, Luis M.; Gareta, Raquel [Centro de Investigacin de Recursos y Consumos Energeticos (CIRCE), Universidad de Zaragoza, Centro Politecnico Superior, Mareda de Luna, 3, Zaragoza 50018, (Spain)

    2006-12-15

    Renewable energy sources are essential paths towards sustainable development and CO{sub 2} emission reduction. For example, the European Union has set the target of achieving 22% of electricity generation from renewable sources by 2010. However, the extensive use of this energy source is being avoided by some technical problems as fouling and slagging in the surfaces of boiler heat exchangers. Although these phenomena were extensively studied in the last decades in order to optimize the behaviour of large coal power boilers, a simple, general and effective method for fouling control has not been developed. For biomass boilers, the feedstock variability and the presence of new components in ash chemistry increase the fouling influence in boiler performance. In particular, heat transfer is widely affected and the boiler capacity becomes dramatically reduced. Unfortunately, the classical approach of regular sootblowing cycles becomes clearly insufficient for them. Artificial Intelligence (AI) provides new means to undertake this problem. This paper illustrates a methodology based on Neural Networks (NNs) and Fuzzy-Logic Expert Systems to select the moment for activating sootblowing in an industrial biomass boiler. The main aim is to minimize the boiler energy and efficiency losses with a proper sootblowing activation. Although the NN type used in this work is well-known and the Hybrid Systems had been extensively used in the last decade, the excellent results obtained in the use of AI in industrial biomass boilers control with regard to previous approaches makes this work a novelty. (Author)

  4. Optimization of feed water control for auxiliary boiler

    International Nuclear Information System (INIS)

    Li Lingmao

    2004-01-01

    This paper described the feed water control system of the auxiliary boiler steam drum in Qinshan Phase III Nuclear Power Plant, analyzed the deficiency of the original configuration, and proposed the optimized configuration. The optimized feed water control system can ensure the stable and safe operation of the auxiliary boiler, and the normal operation of the users. (author)

  5. Assessment of the candidate markets for liquid boiler fuels

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-12-01

    Liquid fuels can be produced from coal in a number of indirect and direct liquefaction processes. While indirect coal liquefaction has been proved commercially outside the United States, most attention in this country has focused on the direct liquefaction processes, which include the processes under examination in this report; namely, the Exxon Donor Solvent (EDS), the H-Coal, and the Solvent Refined Coal (SRC) II processes. The objectives of the study were to: compare the boiler fuels of direct coal liquefaction with residual fuel oil (No. 6 fuel oil) including physical characteristics and environmental hazards, such as carcinogenic characteristics and toxic hazard characteristics; determine whether a boiler fuel market would exist for the coal liquefaction products given their physical characteristics and potential environmental hazards; determine the advantages of utilizing methanol as a boiler fuel on a continuous basis in commercial boilers utilizing existing technology; identify the potential regional candidate markets for direct coal liquefaction products as liquid boiler fuels; determine the distributing and handling costs associated with marketing coal liquefaction products as liquid boiler fuels; determine the current regulatory issues associated with the marketing of coal liquefaction products as boiler fuels; and determine and evaluate other institutional issues associated with the marketing of direct coal liquefaction products as boiler fuels.

  6. Estimation of Scale Deposition in the Water Walls of an Operating Indian Coal Fired Boiler: Predictive Modeling Approach Using Artificial Neural Networks

    Science.gov (United States)

    Kumari, Amrita; Das, Suchandan Kumar; Srivastava, Prem Kumar

    2016-04-01

    Application of computational intelligence for predicting industrial processes has been in extensive use in various industrial sectors including power sector industry. An ANN model using multi-layer perceptron philosophy has been proposed in this paper to predict the deposition behaviors of oxide scale on waterwall tubes of a coal fired boiler. The input parameters comprises of boiler water chemistry and associated operating parameters, such as, pH, alkalinity, total dissolved solids, specific conductivity, iron and dissolved oxygen concentration of the feed water and local heat flux on boiler tube. An efficient gradient based network optimization algorithm has been employed to minimize neural predictions errors. Effects of heat flux, iron content, pH and the concentrations of total dissolved solids in feed water and other operating variables on the scale deposition behavior have been studied. It has been observed that heat flux, iron content and pH of the feed water have a relatively prime influence on the rate of oxide scale deposition in water walls of an Indian boiler. Reasonably good agreement between ANN model predictions and the measured values of oxide scale deposition rate has been observed which is corroborated by the regression fit between these values.

  7. Reconstruction of industrial boiler type DKVR-13 aiming for combustion of waste materials from oil-yielding production

    International Nuclear Information System (INIS)

    Gadzhanov, P.

    1997-01-01

    One of the methods for improving of the energy efficiency is the use of a secondary energy resources such as waste products from industrial processes. In case of the oil extraction a great amount of waste product (sunflower shells) with a good thermal potential is available. During the industrial process from 100 kg raw material 15 kg shells are obtained. The combustion heat is about 1700 kJ/kg. The volatile compounds yield is 66.1%. An installation has been constructed intended to use the waste product from the extraction, consisting of: a water tube boiler with a steam capacity of 20 t/h and two PKM-12 type flue boilers and two DKVR 10-13 type water tube boilers. The DKVR 10-13 type boilers are designed for the production of 22.77 kg/s saturated steam with pressure 1.28 MPa and temperature 194 o C. They have an unified constructional schemes with a two-drum evaporating system and a natural circulation. The furnace has a horizontally evaporation beam washed by the gas flux. The reconstruction is aimed to create condition for the use of the sunflower shells as a main fuel and the natural gas or other fuel as additional. The scheme is one using the sloping bed combustion. 70% of the steam production is due to the shells combustion. Calculations for the grid parameters have been done. An additional heater improves the efficiency with 4.5% and the expected annual fuel saving is 300 t. The introduction of hot air (165 o C) provides both combustion and ecological benefits

  8. A theoretical approach for energy saving in industrial steam boilers

    International Nuclear Information System (INIS)

    Sabry, T.I.; Mohamed, N.H.; Elghonimy, A.M.

    1993-01-01

    Optimization of the performance characteristics of such a steam boiler has been analyzed theoretically. Suitable thermodynamic relations have been utilized here to construct a computer model that would carry out the boiler performance characteristics at different operating parameters (e.g.; amount of excess air, fuel type, rate of blowdown preheating of combustion air and flow gases temperature). The results demonstrate that this computer model is to be used successfully in selecting the different operating parameters of the steam boiler at variant loads considering the best economical operation. Besides, this model can be used to investigate the sensitivity of the performance characteristics to the deviation of the boiler operating parameters from their optimum values. It was found also that changing the operating parameters beside the type of fuel in a boiler affects its performance characteristics. 3 figs

  9. The structure and behavior of salts in kraft recovery boilers

    Energy Technology Data Exchange (ETDEWEB)

    Backman, R.; Badoi, R.D.; Enestam, S. [Aabo Akademi Univ., Turku (Finland). Combustion Chemistry Research Group

    1997-10-01

    The melting behavior in the salt system (Na,K)(CO{sub 3},SO{sub 4},S,Cl,OH) is investigated by laboratory methods to enhance and further develop a chemical model for salt mixtures with compositions relevant for recovery boilers. The model, based on both literature data and experimental work can be used as (a) submodel in models for the over-all chemistry in recovery boilers and to estimate (b) deposit formation on heat transfer surfaces (fouling), (c) the melting properties of the fly ash, and (d) the smelt bed in recovery boilers. Experimental techniques used are thermal analysis, high temperature microscopy` and scanning electron microscopy. The model is implemented in a global calculation model which can handle both gas phases and condensed phases in the recovery boiler. The model gives a detailed description of the chemical reactions involved in the fume and dust formation in different locations of the flue gas channel in the boiler. (orig.)

  10. Boiling process modelling peculiarities analysis of the vacuum boiler

    Science.gov (United States)

    Slobodina, E. N.; Mikhailov, A. G.

    2017-06-01

    The analysis of the low and medium powered boiler equipment development was carried out, boiler units possible development directions with the purpose of energy efficiency improvement were identified. Engineering studies for the vacuum boilers applying are represented. Vacuum boiler heat-exchange processes where boiling water is the working body are considered. Heat-exchange intensification method under boiling at the maximum heat- transfer coefficient is examined. As a result of the conducted calculation studies, heat-transfer coefficients variation curves depending on the pressure, calculated through the analytical and numerical methodologies were obtained. The conclusion about the possibility of numerical computing method application through RPI ANSYS CFX for the boiling process description in boiler vacuum volume was given.

  11. Biomass boilers: towards a higher efficiency

    International Nuclear Information System (INIS)

    Petitot, Pauline; Signoret, Stephane; Mary, Olivier; Dejeu, Mathieu; Tachet, Jean-Pierre

    2014-01-01

    A set of articles proposes an overview of the situation and perspectives of biomass fuelled boilers in France. As outlined in an interview, professionals are supported by ADEME and the Heat Fund (Fonds Chaleur) for a continuous development of wood-energy in order to reach national objectives for renewable energies by 2020. The next article discusses issues related to wood supply, with some concerns regarding forest exploitation, and needs to find new management ways and to use other sources than forests. The technical status and perspectives of smoke condensation in wood-fuelled boilers are discussed. The example of a malt-house near Issoudun fuelled by biomass since 2013 is presented. Other examples concern a small town of Burgundy which developed and is still improving a heat network, a wood-fuelled heat network in Saint-Denis, and a biomass wood-fuelled heat production plant for the Toulouse University hospital. Graphs indicate evolutions of prices for different wood-based fuel products. The last article outlines the role of forests and the importance of their protection in the struggle against climate change, and discusses problems faced to support this preservation and its financing

  12. Mercury emissions from polish pulverized coalfired boiler

    Directory of Open Access Journals (Sweden)

    Wichliński Michał

    2017-01-01

    Full Text Available The current paper presents the research results carried out at one of Polish power plants at a pulverized hard coal-fired 225 MW unit. The research was carried out at full load of the boiler (100% MCR and focused on analysis of mercury content in the input fuel and limestone sorbent for wet flue gas desulfurization (FGD system, as well as investigation of mercury content in the combustion products, i.e. fly ash, slag, FGD product (gypsum and FGD effluents (waste. Within the framework of the present study the concentration of mercury vapor in the exhaust gas was also investigated. The analysis was performed using Lumex RA-915+ spectrometer with an attachment (RP-91C. The measurements were carried out at three locations, i.e. before the electrostatic precipitator (ESP, downstream the ESP, and downstream the wet FGD plant. Design of the measurement system allowed to determine both forms of mercury in the flue gas (Hg0 and Hg2+ at all measurement locations.Based on the measurement results the balance of mercury for a pulverized coal (PC boiler was calculated and the amount of mercury was assessed both in the input solids (fuel and sorbent, as well as the gaseous and solids products (flue gas, slag, ash, gypsum and FGD waste.

  13. Code boiler and pressure vessel life assessment

    International Nuclear Information System (INIS)

    Farr, J.R.

    1992-01-01

    In the United States of America and in Canada, laws and controls for determining life assessment for continued operation of equipment exist only for those pressure vessels built to Section III and evaluated according to Section XI. In this presentation, some of those considerations which are made in the USA and Canada for deciding on life or condition assessment of boilers and pressure vessels designed and constructed to other sections of the ASME Boiler and Pressure Vessel Code are reviewed. Life assessment or condition assesssment is essential in determining what is necessary for continued operation. With no ASME rules being adopted by laws or regulations, other than OSHA in the USA and similar environmental controls in Canada, to control life assessment for continued operation, the equipment owner must decide if assessment is to be done and how much to do. Some of those considerations are reviewed along with methods and procedures to make an assessment along with a discussion of where the ASME B and PV Code currently stands regarding continued operation. (orig.)

  14. Establishing an energy efficiency recommendation for commercial boilers

    International Nuclear Information System (INIS)

    Ware, Michelle J.

    2000-01-01

    To assist the federal government in meeting its energy reduction goals, President Clinton's Executive Order 12902 established the Procurement Challenge, which directed all federal agencies to purchase equipment within the top 25th percentile of efficiency. Under the direction of DOE's Federal Energy Management Program (FEMP), the Procurement Challenge's goal is to create efficiency recommendations for all energy-using products that could substantially impact the government's energy reduction goals, like commercial boilers. A typical 5,000,000 Btuh boiler, with a thermal efficiency of 83.2%, can have lifetime energy cost savings of$40,000 when compared to a boiler with a thermal efficiency of 78%. For the federal market, which makes up 2% of the boiler market, this means lifetime energy cost savings of over$25,600,000. To establish efficiency recommendations, FEMP uses standardized performance ratings for products sold in the marketplace. Currently, the boiler industry uses combustion efficiency and, sometimes, thermal efficiency performance measures when specifying a commercial boiler. For many years, the industry has used these efficiency measures interchangeably, causing confusion about boiler performance measurements, and making it difficult for FEMP to establish the top 25th percentile of efficiency. This paper will illustrate the method used to establish FEMP's recommendation for boilers. The method involved defining a correlation between thermal and combustion efficiency among boiler classifications; using the correlation to model a data set of all the boiler types available in the market; and identifying how the correlation affected the top 25th percentile analysis. The paper also will discuss the applicability of this method for evaluating other equipment for which there are limited data on performance ratings

  15. A study of burning processes of fossil fuels in straitened conditions of furnaces in low capacity boilers by an example of natural gas

    Science.gov (United States)

    Roslyakov, P. V.; Proskurin, Y. V.; Khokhlov, D. A.; Zaichenko, M. N.

    2018-03-01

    The aim of this work is to research operations of modern combined low-emission swirl burner with a capacity of 2.2 MW for fire-tube boiler type KV-GM-2.0, to ensure the effective burning of natural gas, crude oil and diesel fuel. For this purpose, a computer model of the burner and furnace chamber has been developed. The paper presents the results of numerical investigations of the burner operation, using the example of natural gas in a working load range from 40 to 100%. The basic features of processes of fuel burning in the cramped conditions of the flame tube have been identified to fundamentally differ from similar processes in the furnaces of steam boilers. The influence of the design of burners and their operating modes on incomplete combustion of fuel and the formation of nitrogen oxides has been determined.

  16. Application of laser-based profilometry to tubing in power generating utilities

    Science.gov (United States)

    Doyle, James L.

    1995-05-01

    Over the past several years lasers have been employed in an ever widening number of applications in an incredibly diverse set of markets. In the area of nondestructive testing, however, laser-based systems have only recently made inroads into the commercial markets. About ten years ago QUEST Integrated, Inc., began working with the U.S. Navy to adapt the principal of laser triangulation to solve a serious maintenance related problem. The internal surfaces of marine boiler tubes were experiencing pitting and corrosion which had resulted in catastrophic shipboard failures. At that time, conventional visual methods only allowed operators to inspect the first eighteen inches of the tube using a rigid borescope. If any pits were located, a mechanical stylus mechanism was used to obtain an approximate depth measurement of the pit. The condition of the balance of the tube was then extrapolated based on this extremely limited amount of information. Often the worst pitting was found in the bends of the tube, which could not be inspected by the visual method. Finally, a catastrophic boiler failure on an aircraft carrier resulted in the initiation of a search by the U.S. Navy for a better solution. Quest was contracted to develop an articulated probe which could negotiate the full length of a boiler tube with multiple bends, and generate a complete digital map of the inside surface. A key requirement of this probe would be rapid and quantitative measurement of internal features such as ID pits and corrosion. In 1987 QUEST delivered the first laser- optic tube inspection system to the U.S. Navy for use in marine boiler tubes. The Laser Optic Tube Inspection System (LOTISTM) was immediately put to use and paid for itself many times over in reduced maintenance costs. Over the next six years several generations of LOTIS were developed for the U.S. Navy, each one providing more capabilities, improved inspection speeds, and more user friendly operator interface. Today, LOTIS is

  17. Eustachian tube patency

    Science.gov (United States)

    Eustachian tube patency refers to how much the eustachian tube is open. The eustachian tube runs between the middle ear and the throat. It controls the pressure behind the eardrum and middle ear space. This helps keep ...

  18. Feeding tube - infants

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/007235.htm Feeding tube - infants To use the sharing features on this page, please enable JavaScript. A feeding tube is a small, soft, plastic tube placed ...

  19. An adaptation of the Citrosolv process to remove different types of deposits in boilers of a thermo-electric power plant

    International Nuclear Information System (INIS)

    Ferreira, V.C.

    1985-01-01

    During the inspection of a power station boiler was find out a high amount of scale/deposits on the tubes surface (> 100 mg/cm 2 ). The scale/deposits constituents determined in chemical analysis, X-ray fluorescence and X-ray diffraction were iron, copper, calcium, magnesium, phosphorus and silicon. A chemical cleaning based on a small change of Citrosolv process, was used to remove those scale/deposits with sucess. (Author) [pt

  20. Development of heat transfer calculation program for finned-tune heat exchanger of multi-burner boiler

    International Nuclear Information System (INIS)

    Jang, Sae Byul; Kim, Jong Jin; Ahn, Joon

    2009-01-01

    We develop a heat exchanger modules for a multi-burner boiler. The heat exchanger module is kind of a Heat Recovery Steam Generator (HRSG). This heat recovery system has 8 heat exchanger modules. The 1st module consists of 27 bare tubes due to high temperature exhaust gas and the others consist of 27 finned tubes. The maximum steam pressure of each module is 1 MPa and tested steam pressure is 0.7 MPa. In order to test these heat exchanger modules, we make a 0.5 t/h flue tube boiler (LNG, 40 Nm 3 /h). We tested the heat exchanger module with changing the position of each heat exchanger module. We measured the inlet and outlet temperature of each heat exchanger module and calculated the heat exchange rate. Based on test results, we develop a heat transfer calculation program to predict flue gas. Calculation results show that temperature and temperature difference between measured and calculated flue gas exit temperature is less than 20 .deg. C when flue gas inlet temperature is 620 .deg. C.

  1. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman

    2003-01-20

    The principal objective of this project is to develop materials technology for use in ultrasupercritical (USC) plant boilers capable of operating with 760 C (1400 F), 35 MPa (5000 psi) steam. In the 21st century, the world faces the critical challenge of providing abundant, cheap electricity to meet the needs of a growing global population while at the same time preserving environmental values. Most studies of this issue conclude that a robust portfolio of generation technologies and fuels should be developed to assure that the United States will have adequate electricity supplies in a variety of possible future scenarios. The use of coal for electricity generation poses a unique set of challenges. On the one hand, coal is plentiful and available at low cost in much of the world, notably in the U.S., China, and India. Countries with large coal reserves will want to develop them to foster economic growth and energy security. On the other hand, traditional methods of coal combustion emit pollutants and CO{sub 2} at high levels relative to other generation options. Maintaining coal as a generation option in the 21st century will require methods for addressing these environmental issues. This project has established a government/industry consortium to undertake a five-year effort to evaluate and develop of advanced materials that allow the use of advanced steam cycles in coal-based power plants. These advanced cycles, with steam temperatures up to 760 C, will increase the efficiency of coal-fired boilers from an average of 35% efficiency (current domestic fleet) to 47% (HHV). This efficiency increase will enable coal-fired power plants to generate electricity at competitive rates (irrespective of fuel costs) while reducing CO{sub 2} and other fuel-related emissions by as much as 29%. Success in achieving these objectives will support a number of broader goals. First, from a national prospective, the program will identify advanced materials that will make it possible to

  2. Factors in the selection of broiler tube materials for a civil fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    Tyzack, C; Chitty, A

    1975-07-01

    This paper briefly considers some of the factors which must be balanced in the selection of a boiler tube material for a Civil Fast Reactor. The merits and possible demerits of low alloy ferritic steels and the austenitic Alloy 800 are compared with respect to waterside corrosion resistance, mechanical properties, fabrication and weldability and possible effects of exposure to the sodium environment under normal and fault conditions. It is pointed out that although there is operational experience of most of the materials in boiler superheater applications there is little or none in evaporative regimes. (author)

  3. Tube holding system

    International Nuclear Information System (INIS)

    Cunningham, R.C.

    1978-01-01

    A tube holding rig is described for the lateral support of tubes arranged in tight parcels in a heat exchanger. This tube holding rig includes not less than two tube supporting assemblies, with a space between them, located crosswise with respect to the tubes, each supporting assembly comprising a first set of parallel components in contact with the tubes, whilst a second set of components is also in contact with the tubes. These two sets of parts together define apertures through which the tubes pass [fr

  4. A novel direct-fired porous-medium boiler

    Science.gov (United States)

    Prasartkaew, Boonrit

    2018-01-01

    Nowadays, power and heat generation systems pay an important role in all economic sectors. These systems are mainly based on combustion reaction and operated under the second law of thermodynamics. A conventional boilers, a main component of heat and power generators, have thermal efficiency in the range of 70 to 85%, mainly owing to they have flue gas heat loss. This paper proposes a novel type of boiler, called a Direct-fired Porous-medium Boiler (DPB). Due to being operated without flue gas heat loss, its thermal efficiency cloud be approximately close to 100%. The steam produced from the proposed boiler; however, is not pure water steam. It is the composite gases of steam and combustion-product-gases. This paper aims at presenting the working concept and reporting the experimental results on the performance of the proposed boiler. The experiments of various operating parameters were performed and collected data were used for the performance analysis. The experimental results demonstrated that the proposed boiler can be operated as well as the conceptual design and then it is promising. It can be possibly further developed to be a high efficiency boiler by means of reducing or suppressing the surface heat loss with better insulator and/or refractory lined.

  5. Cross connecting absorber module inlets of multiple boiler units

    International Nuclear Information System (INIS)

    Cirillo, A.J.; Sperber, P.K.; Belavadi, V.N.; Mukherji, A.

    1991-01-01

    The retrofitting of scrubbers downstream of existing balanced draft boilers is often accomplished by the addition of induced draft (ID) booster fans. By creating a common plenum between the ID fans and the ID booster fans of two or more boiler-absorber trains, absorber module capacity may be shared among multiple boiler units. At Harrison Power Station, three (3) 4,900,000 lb/hour boilers (640 MWe Gross) will be linked through a common plenum. This sharing capability precludes the need to add standby module capacity, thereby saving capital dollars and keeping project critical path schedules, which typically run through absorber procurement and construction, to a minimum. Through damper placement in the ductwork cross connections, unitized boiler-absorber module operation or common plenum operation may be obtained, thus providing both operational flexibility and reliability. Additionally, open plenum operation allows the removal of an absorber unit from service, while keeping its associated boiler on line, thereby precluding 'cold starts' and maintaining overall unit availabilities. As either unitized or common plenum operation is possible with the cross connection, the furnace draft control systems of each boiler must be examined for varying load operation and trip conditions. This paper addresses the means by which to analyze such cross connection operational scenarios while maintaining compliance with furnace flame out safety guidelines, and will discuss the physical design considerations, ramifications and benefits of same, with select emphasis on what is being implemented at the Harrison Power Station

  6. Supercritical boiler material selection using fuzzy analytic network process

    Directory of Open Access Journals (Sweden)

    Saikat Ranjan Maity

    2012-08-01

    Full Text Available The recent development of world is being adversely affected by the scarcity of power and energy. To survive in the next generation, it is thus necessary to explore the non-conventional energy sources and efficiently consume the available sources. For efficient exploitation of the existing energy sources, a great scope lies in the use of Rankin cycle-based thermal power plants. Today, the gross efficiency of Rankin cycle-based thermal power plants is less than 28% which has been increased up to 40% with reheating and regenerative cycles. But, it can be further improved up to 47% by using supercritical power plant technology. Supercritical power plants use supercritical boilers which are able to withstand a very high temperature (650-720˚C and pressure (22.1 MPa while producing superheated steam. The thermal efficiency of a supercritical boiler greatly depends on the material of its different components. The supercritical boiler material should possess high creep rupture strength, high thermal conductivity, low thermal expansion, high specific heat and very high temperature withstandability. This paper considers a list of seven supercritical boiler materials whose performance is evaluated based on seven pivotal criteria. Given the intricacy and difficulty of this supercritical boiler material selection problem having interactions and interdependencies between different criteria, this paper applies fuzzy analytic network process to select the most appropriate material for a supercritical boiler. Rene 41 is the best supercritical boiler material, whereas, Haynes 230 is the worst preferred choice.

  7. Up-date on cyclone combustion and cyclone boilers

    Energy Technology Data Exchange (ETDEWEB)

    Carmo, Felipe Alfaia do; Nogueira, Manoel Fernandes Martins; Rocha, Rodrigo Carnera Castro da; Gazel, Hussein Felix; Martins, Diego Henrique dos Reis [Universidade Federal do Para (UFPA), Belem, PA (Brazil). Campus Universitario Jose da Silveira Netto], E-mails: mfmn@ufpa.br, mfmn@ufpa.br

    2010-07-01

    The boiler concept has been around for more than 70 years, and there are many types available. Boilers provide steam or hot water for industrial and commercial use. The Federal University of Para (UFPA) through the research group EBMA (Energy,Biomass and Environment) has been developing cyclonic furnace with a water wall, a boiler, aiming to use regional timbers (sawdust) and agro-industries residues as fuel to produce steam to be used in industrial processes as well as in power generation,. The use of cyclonic combustion for burning waste instead of burning in a fixed bed is mainly due to two factors efficiency improvement causing a more compact boiler and less risk of explosion, since their process does not generate an accumulation of volatile. Present state-of-art for commercial cyclone boilers has as set up a cyclone combustor with two combustion chambers, in fluid communication, where there ducts for supplying air and fuel directly into the first chamber and for forming a cyclonic flow pattern and a heat exchanger surrounding the second chamber for keeping low combustion temperature in both chambers. This paper shows the results of a literature review about design, construction and operation of cyclonic boilers using solid, liquid or gaseous fuel. This information has been used for the design of a cyclone boiler to be constructed at UFPA for research purposes and its basic concept is presented at the end of this article. (author)

  8. Evaluation of conditions of SNCR in small boilers

    International Nuclear Information System (INIS)

    Kullendorff, A.; Lorentzon, K.

    1996-04-01

    The report describes the first part of a project 'SNCR for small boilers', supported by Vaermeforsk (Thermal Engineering Research Institute), with the purpose of assessing the potential for SNCR in small boilers. Given favourable conditions, the project was to be continued in a second part with the demonstration of a SNCR system in a small boiler (or several boilers). During the base establishment, the temperatures in four locations per boiler, in a couple of horizontal or vertical levels and at 2-3 thermal outputs, were measured. Out of the four locations two showed temperatures mainly within the theoretical temperature window for SNCR. These locations were used during the try-out tests to inject urea and ammonia. The locations and the equipment used during the try-out tests together with existing operation strategies seem to limit the reduction levels to approximately 10-20% at acceptable levels of ammonia slip. The measurements and try-out tests carried out does not provide enough basis for forming any general conclusions concerning SNCR in small boilers. Neither the base establishment nor the try-out tests included any optimisation of the boilers regarding the operation strategy or, for the try-out tests, locations and equipment (drop size, flow shape and direction). Therefore, it is likely to believe that better results can be obtained, given other conditions of operation and using well established SNCR technology, adapted to the circumstances. 2 refs, 27 figs, 5 tabs

  9. 46 CFR 52.20-17 - Opening between boiler and safety valve (modifies PFT-44).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Opening between boiler and safety valve (modifies PFT-44). 52.20-17 Section 52.20-17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING POWER BOILERS Requirements for Firetube Boilers § 52.20-17 Opening between boiler and safety valve...

  10. 40 CFR 266.110 - Waiver of DRE trial burn for boilers.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Waiver of DRE trial burn for boilers... HAZARDOUS WASTE MANAGEMENT FACILITIES Hazardous Waste Burned in Boilers and Industrial Furnaces § 266.110 Waiver of DRE trial burn for boilers. Boilers that operate under the special requirements of this section...

  11. 9 CFR 91.22 - Protection from heat of boilers and engines.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Protection from heat of boilers and... Protection from heat of boilers and engines. No animals shall be stowed along the alleyways leading to the engine or boiler rooms unless the sides of said engine or boiler rooms are covered by a tongue and groove...

  12. 46 CFR 91.15-1 - Standards in inspection of hulls, boilers, and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Standards in inspection of hulls, boilers, and machinery... hulls, boilers, and machinery. In the inspection of hulls, boilers, and machinery of vessels, the..., respecting material and inspection of hulls, boilers, and machinery, and the certificate of classification...

  13. 30 CFR 57.13001 - General requirements for boilers and pressure vessels.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false General requirements for boilers and pressure... NONMETAL MINES Compressed Air and Boilers § 57.13001 General requirements for boilers and pressure vessels. All boilers and pressure vessels shall be constructed, installed, and maintained in accordance with...

  14. 40 CFR 63.7506 - Do any boilers or process heaters have limited requirements?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 13 2010-07-01 2010-07-01 false Do any boilers or process heaters have..., and Institutional Boilers and Process Heaters General Compliance Requirements § 63.7506 Do any boilers or process heaters have limited requirements? (a) New or reconstructed boilers and process heaters in...

  15. 46 CFR 189.15-1 - Standards in inspection of hulls, boilers, and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Standards in inspection of hulls, boilers, and machinery... inspection of hulls, boilers, and machinery. In the inspection of hulls, boilers, and machinery of vessels... chapter, respecting material and construction of hulls, boilers, and machinery, and certificate of...

  16. 49 CFR 230.20 - Alteration and repair report for steam locomotive boilers.

    Science.gov (United States)

    2010-10-01

    ... boilers. 230.20 Section 230.20 Transportation Other Regulations Relating to Transportation (Continued... boilers. (a) Alterations. When an alteration is made to a steam locomotive boiler, the steam locomotive... maintained for the life of the boiler. (See appendix B of this part.) (b) Welded and riveted repairs to...

  17. 46 CFR 61.05-5 - Preparation of boilers for inspection and test.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Preparation of boilers for inspection and test. 61.05-5... PERIODIC TESTS AND INSPECTIONS Tests and Inspections of Boilers § 61.05-5 Preparation of boilers for... preparing the boilers for the hydrostatic test, they shall be filled with water at not less than 70 °F. and...

  18. 40 CFR 63.7491 - Are any boilers or process heaters not subject to this subpart?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 13 2010-07-01 2010-07-01 false Are any boilers or process heaters not..., and Institutional Boilers and Process Heaters What This Subpart Covers § 63.7491 Are any boilers or process heaters not subject to this subpart? The types of boilers and process heaters listed in paragraphs...

  19. 40 CFR 63.7499 - What are the subcategories of boilers and process heaters?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 13 2010-07-01 2010-07-01 false What are the subcategories of boilers..., and Institutional Boilers and Process Heaters Emission Limits and Work Practice Standards § 63.7499 What are the subcategories of boilers and process heaters? The subcategories of boilers and process...

  20. 46 CFR 71.15-1 - Standards in inspection of hulls, boilers, and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Standards in inspection of hulls, boilers, and machinery..., boilers, and machinery. In the inspection of hulls, boilers, and machinery of vessels, the standards... and inspection of hulls, boilers, and machinery, and the certificate of classification referring...

  1. 30 CFR 56.13001 - General requirements for boilers and pressure vessels.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false General requirements for boilers and pressure... MINES Compressed Air and Boilers § 56.13001 General requirements for boilers and pressure vessels. All boilers and pressure vessels shall be constructed, installed, and maintained in accordance with the...

  2. Three-dimensional computer simulation for combustion and NO{sub x} emission in a grate fired boiler at Baeckhamars, Sweden. Technical report[(Baeckhammars Bruk)

    Energy Technology Data Exchange (ETDEWEB)

    Dong Wei [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Metallurgy

    2000-05-01

    This report describes the fundament of mathematical modeling for the grate fired boilers in Part A, and presents the results from the numerical simulations for the flow pattern, combustion and NO{sub x} emission in the Baeckhammars grate fired boiler in Part B. The simulated boiler is equipped with a new secondary air supply system called Ecotube. The objective of this project is to develop and experimentally verify tools for computer simulations of solid biomass fuel combustion processes in a grate fired boiler. The work focuses on the numerical simulation using CFD technique and development of a NO{sub x} post processor. The unstructured mesh technique also has been used to discretize the boiler. An unstructured grid with total 284399 tetrahedral cells describes the three dimensional geometry and is used for flow field and combustion simulations. In order to simulate the combustion process in the boiler, a simplified grate bed model -- black-box bed model is used, which is based on the balance analysis of mass and energy on the grate bed and needless to consider any detailed and very difficult dynamic processes which have not been valuable by mathematical modeling on the grate bed yet. Therefore, it is quite convenient for industrial applications. In this work, both the cyanide route and the ammonia route for modeling the fuel containing nitrogen NO{sub x} are developed, and the former has been used to predict the NO generation in Baeckhammars bark boiler. Two 3D cases corresponding to 15 MW and 11 MW output thermal power respectively are simulated in detail. Results show that a new air supply system called Ecotube gives a considerably more uniform velocity, temperature and concentration distribution from the secondary air tubes to the upper part of the furnace. The upper furnace works almost as a 'plug flow reactor' which gives sufficient residence time for CO conversion and low NO{sub x} emission. The calculations of flow and mixing patterns in the

  3. Active brickworks - phase I[For application in biofuel boilers]; Aktiva murverk - etapp I

    Energy Technology Data Exchange (ETDEWEB)

    Wrangensten, Lars; Schuster, Robert; Ingman, Rolf; Sendelius, Mikael; Ehleskog, Rickard [AaF-Energikonsult AB, Stockholm (Sweden)

    2003-10-01

    This report is the first step of the R and D project 'Active brickworks' within the program 'Possibilities to improve the operation conditions in industrial bark boilers by optimised combustion control'. Good high temperature resistance is one of the major characteristics of ceramics. They are based on quartz and aluminium oxide, an attachment component (acid or cement) and also different types of additives which, together with the heating treatment, gives the ceramic materials their features. The brickwork in a boiler has several assignments. First of all resistance to corrosion, erosion and protection against fouling of the water tube walls, but also to significant affect the combustion process by energy saving features and heating radiation. This project has been focused on the last named features, namely to be able to make a more active choice of brickwork in order to utilise the ceramic features and hereby making it possible to lower the combustion process emissions. The material samples received from the manufactures have been tested in a small-scale laboratory rig. Features investigated are emissivity/reflection, heat conductivity and heat capacity. Mathematic simulations have also been performed with a representative type boiler model in order to make conclusions concerning how the results can be transformed to and applied in a real full-scale boiler. The most important designing case for ceramics in bark boilers is when boiler load rapidly increases or during a fast fuel moisture change from dry to wet fuel. It has been concluded in the study that that the ceramic walls in a boiler should be divided into different layers. The outer layer in the ceiling and sidewalls of the drying zone must consist of highly insulating material in order to get a high temperature of heating surfaces close to the furnace. To store heat during load transients the heating surfaces must have high emissivity factor and good heating capacity. From this point of

  4. Apparatus and method of controlling the thermal performance of an oxygen-fired boiler

    Science.gov (United States)

    Levasseur, Armand A.; Kang, Shin G.; Kenney, James R.; Edberg, Carl D.

    2017-09-05

    Disclosed herein is a method of controlling the operation of an oxy-fired boiler; the method comprising combusting a fuel in a boiler; producing a heat absorption pattern in the boiler; discharging flue gases from the boiler; recycling a portion of the flue gases to the boiler; combining a first oxidant stream with the recycled flue gases to form a combined stream; splitting the combined stream into several fractions; and introducing each fraction of the combined stream to the boiler at different points of entry to the boiler.

  5. Failure Analysis Of Industrial Boiler Pipe

    International Nuclear Information System (INIS)

    Natsir, Muhammad; Soedardjo, B.; Arhatari, Dewi; Andryansyah; Haryanto, Mudi; Triyadi, Ari

    2000-01-01

    Failure analysis of industrial boiler pipe has been done. The tested pipe material is carbon steel SA 178 Grade A refer to specification data which taken from Fertilizer Company. Steps in analysis were ; collection of background operation and material specification, visual inspection, dye penetrant test, radiography test, chemical composition test, hardness test, metallography test. From the test and analysis result, it is shown that the pipe failure caused by erosion and welding was shown porosity and incomplete penetration. The main cause of failure pipe is erosion due to cavitation, which decreases the pipe thickness. Break in pipe thickness can be done due to decreasing in pipe thickness. To anticipate this problem, the ppe will be replaced with new pipe

  6. CHP Integrated with Burners for Packaged Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Castaldini, Carlo; Darby, Eric

    2013-09-30

    The objective of this project was to engineer, design, fabricate, and field demonstrate a Boiler Burner Energy System Technology (BBEST) that integrates a low-cost, clean burning, gas-fired simple-cycle (unrecuperated) 100 kWe (net) microturbine (SCMT) with a new ultra low-NOx gas-fired burner (ULNB) into one compact Combined Heat and Power (CHP) product that can be retrofit on new and existing industrial and commercial boilers in place of conventional burners. The Scope of Work for this project was segmented into two principal phases: (Phase I) Hardware development, assembly and pre-test and (Phase II) Field installation and demonstration testing. Phase I was divided into five technical tasks (Task 2 to 6). These tasks covered the engineering, design, fabrication, testing and optimization of each key component of the CHP system principally, ULNB, SCMT, assembly BBEST CHP package, and integrated controls. Phase I work culminated with the laboratory testing of the completed BBEST assembly prior to shipment for field installation and demonstration. Phase II consisted of two remaining technical tasks (Task 7 and 8), which focused on the installation, startup, and field verification tests at a pre-selected industrial plant to document performance and attainment of all project objectives. Technical direction and administration was under the management of CMCE, Inc. Altex Technologies Corporation lead the design, assembly and testing of the system. Field demonstration was supported by Leva Energy, the commercialization firm founded by executives at CMCE and Altex. Leva Energy has applied for patent protection on the BBEST process under the trade name of Power Burner and holds the license for the burner currently used in the product. The commercial term Power Burner is used throughout this report to refer to the BBEST technology proposed for this project. The project was co-funded by the California Energy Commission and the Southern California Gas Company (SCG), a

  7. Physical and Numerical Analysis of Extrusion Process for Production of Bimetallic Tubes

    Energy Technology Data Exchange (ETDEWEB)

    Misiolek, W.Z.; Sikka, V.K.

    2006-08-10

    Bimetallic tubes are used for very specific applications where one of the two metals provides strength and the other provides specific properties such as aqueous corrosion and carburization, coking resistance, and special electrical and thermal properties. Bimetallic tubes have application in pulp and paper industry for heat-recovery boilers, in the chemical industry for ethylene production, and in the petrochemical industry for deep oil well explorations. Although bimetallic tubes have major applications in energy-intensive industry, they often are not used because of their cost and manufacturing sources in the United States. This project was intended to address both of these issues.

  8. Determination of thermal characteristics of combustion products of fire-tube heat generator with flow turbulator

    OpenAIRE

    Lukjanov Alexander V.; Ostapenko Dmitry V.; Basist Dmitry V.

    2014-01-01

    Boiler construction is one of the major industries of any state. The aim is to determine the effect of the turbulator on the intensity of heat transfer in the convective part of the fire-tube heat generator of domestic production. The improvement of convective heating surfaces is one of the ways to increase the energy efficiency of the fire-tube heat generator. Since model of the process of heat transfer of gas flow in the convective tubes is multifactorial and does not have clear analytical ...

  9. Model technique for aerodynamic study of boiler furnace

    Energy Technology Data Exchange (ETDEWEB)

    1966-02-01

    The help of the Division was recently sought to improve the heat transfer and reduce the exit gas temperature in a pulverized-fuel-fired boiler at an Australian power station. One approach adopted was to construct from Perspex a 1:20 scale cold-air model of the boiler furnace and to use a flow-visualization technique to study the aerodynamic patterns established when air was introduced through the p.f. burners of the model. The work established good correlations between the behaviour of the model and of the boiler furnace.

  10. Model-based Control of a Bottom Fired Marine Boiler

    DEFF Research Database (Denmark)

    Solberg, Brian; Karstensen, Claus M. S.; Andersen, Palle

    2005-01-01

    This paper focuses on applying model based MIMO control to minimize variations in water level for a specific boiler type. A first principles model is put up. The model is linearized and an LQG controller is designed. Furthermore the benefit of using a steam °ow measurement is compared to a strategy...... relying on estimates of the disturbance. Preliminary tests at the boiler system show that the designed controller is able to control the boiler process. Furthermore it can be concluded that relying on estimates of the steam flow in the control strategy does not decrease the controller performance...

  11. Numerical modelling of a straw-fired grate boiler

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen

    2004-01-01

    The paper presents a computational fluid dynamics (CFD) analysis of a 33 MW straw-fired grate boiler. Combustion on the grate plays akey-role in the analysis of these boilers and in this work a stand-alone code was used to provide inlet conditions for the CFD analysis. Modelpredictions were...... compared with available gas temperature and species concentration measurements showing good agreement. Combustionof biomass in grate-based boilers is often associated with high emission levels and relatively high amounts of unburnt carbon in the fly ash.Based on the CFD analysis, it is suggested that poor...

  12. Vacuum boilers developed heating surfaces technic and economic efficiency evaluation

    Science.gov (United States)

    Slobodina, E. N.; Mikhailov, A. G.; Semenov, B. A.

    2018-01-01

    The vacuum boilers as manufacturing proto types application analysis was carried out, the possible directions for the heating surfaces development are identified with a view to improving the energy efficiency. Economic characteristics to evaluate the vacuum boilers application efficiency (Net Discounted Income (NDI), Internal Rate of Return (IRR), Profitability Index (PI) and Payback Period) are represented. The given type boilers application technic and economic efficiency criteria were established. NDI changing curves depending on the finning coefficient and operating pressure were obtained as a result of the conducted calculation studies.

  13. An optimising controller for Hinkley Point B AGR boilers

    International Nuclear Information System (INIS)

    Wells, C.

    1986-01-01

    The improvements to the control system at Hinkley Point 'B' Power Station has as one of its objectives the provision of a half unit valve controller. This will enable the asymmetry between the boiler half units, which is a feature of current operation, to be reduced. The use of an on-line boiler model in conjunction with this facility will allow the risk to the boilers from corrosion, creep, and vibration to be assessed and held at the minimum attainable value, thereby prolonging plant life whilst maximising output and efficiency. (author)

  14. Model-based Control of a Bottom Fired Marine Boiler

    DEFF Research Database (Denmark)

    Solberg, Brian; Karstensen, Claus M. S.; Andersen, Palle

    This paper focuses on applying model based MIMO control to minimize variations in water level for a specific boiler type. A first principles model is put up. The model is linearized and an LQG controller is designed. Furthermore the benefit of using a steam °ow measurement is compared to a strategy...... relying on estimates of the disturbance. Preliminary tests at the boiler system show that the designed controller is able to control the boiler process. Furthermore it can be concluded that relying on estimates of the steam flow in the control strategy does not decrease the controller performance...

  15. Economical analyses of construction of a biomass boiler house

    International Nuclear Information System (INIS)

    Normak, A.

    2002-01-01

    To reduce the energy costs we can use cheaper fuel to fire our boiler. One of the cheapest fuels is wood biomass. It is very actual issue how to use cheaper wood biomass in heat generation to decrease energy costs and to increase biomass share in our energy balance. Before we decide to build biomass boiler house it is recommendable to analyse the economical situation and work out most profitable, efficient, reliable and ecological boiler plant design on particular conditions. The best way to perform the analyses is to use the economical model presented. It saves our time and gives objective evaluation to the project. (author)

  16. Orion Ammonia Boiler System Preflight Test Preparations

    Science.gov (United States)

    Levitt, Julia L.

    2017-01-01

    The Environmental Controls and Life Support Systems (ECLSS) branch at Kennedy Space Center (KSC) is currently undergoing preparations for ground testing of the Orion Multi-Purpose Crew Vehicle (MPCV) to prepare its subsystems for EM-1 (Exploration Mission-1). EM-1, Orions second unmanned flight, is a three-week long lunar mission during which the vehicle will complete a 6-day retrograde lunar orbit before returning to Earth. This paper focuses on the work done during the authors 16-week internship with the Mechanical Engineering Branch of KSCs Engineering Directorate. The authors project involved assisting with the preparations for testing the Orion MPCVs ammonia boiler system. The purpose of the ammonia boiler system is to keep the spacecraft sufficiently cool during the reentry portion of its mission, from service module (SM) separation to post-landing. This system is critical for keeping both the spacecraft (avionics and electronics) and crew alive during reentry, thus a successful test of the system is essential to the success of EM-1. XXXX The author was able to draft a detailed outline of the procedure for the ammonia system functional test. More work will need to be done on the vehicle power-up and power-down portions of the procedure, but the ammonia system testing portion of the procedure is thorough and includes vehicle test configurations, vehicle commands, and GSE. The author was able to compile a substantial list of questions regarding the ammonia system functional test with the help of her mentors. A significant number of these questions were answered in the teleconferences with Lockheed Martin.

  17. Feasibility of applying coal-fired boiler technology to process heaters

    Energy Technology Data Exchange (ETDEWEB)

    O' Sullivan, T F

    1978-01-01

    The preponderance of coal in US fossil fuel reserves has raised the question of the conversion of hydrocarbon process heaters to coal firing. A review undertaken in 1977 by an API sub-committee concluded that neither existing heaters nor existing heater designs were capable of modification or revision to burn coal, and that new coal-fired design consistent with process requirements would be needed for this purpose. In recognition of this need a cooperative investigation was undertaken by Combustion Engineering and Lummus. The present paper, reporting on this investigation, reviews existing coal-fired boiler equipment and techniques and describes their adaptation to the development of a design concept for a coal-fired process heater. To this end, the design parameters for both steam boilers and fired heaters have been compared and have been incorporated into a workable coal-fired process heater design which includes the following features; a coutant bottom for ash removal, an ash-hopper located under both radiant and convection chambers, a tangent type finned wall construction, a straight through gas flow pattern, a vertical tube convection section, horizontal firing using round burners, and an overall geometry allowing a coil arrangement capable of accommodating varying numbers of parallel serpentine coils. These features are integrated into a conceptual heater design which is detailed in a series of illustrations.

  18. Wood Pellet-Fired Biomass Boiler Project at the Ketchikan Federal Building

    Energy Technology Data Exchange (ETDEWEB)

    Tomberlin, Gregg [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-06-01

    Biomass boiler systems have existed for many years, but the technology has advanced in recent decades and can now provide automated and efficient operation for a relatively modest investment. Key advances in system monitoring and control allow for lower operating costs, since the control systems run all aspects of the boiler, including feed, load reduction and even tube cleaning. These advances have made such systems economical on a small scale in situations where inexpensive fuels like natural gas are not available. This creates an opportunity for building operators in remote, cold-climate locations to reduce the use of expensive fuels for heating buildings. GSA Region 10 installed the system at the federal building in Ketchikan, Alaska and submitted the project to the Green Proving Ground (GPG) program. GSA's GPG program contracted with the National Renewable Energy Laboratory (NREL) to assess the installation and the technology. The system serves as a demonstration to assess actual system efficiencies, as well as operating characteristics and financial benefits. In addition to installation and operational issues, the project team/researchers examined other issues, including fuel transportation costs, building energy savings, and overall economics.

  19. Study on Influence of Tube Arrays on Fluid Elastic Instability

    Science.gov (United States)

    Ishihara, Kunihiko; Kitayama, Gen

    The tube bank is used in boilers, heat exchangers in power plants and steam generators in nuclear plants. These tubes sometimes vibrate violently and come to the fatigue failure due to the flow induced vibration which is caused by the cross flow. This phenomenon is that the large vibrations arise at the critical flow velocity and it is called fluid elastic instability. However the relation between the onset velocity of fluid elastic instability and the tube array's geometry has not been clarified sufficiently. There is a few reference related to the relation between the pitch to diameter ratio and the onset velocity even in the lattice arrays. In this paper, the influence of tube arrays on fluid elastic instability is examined by experiments. As a result, it is clarified that the tube vibrations become large as T/D increases and L/D decreases, and the tube vibrations strongly depend on the dynamic characteristics of tubes such as the natural frequency and the damping ability.

  20. Theoretical development of a thermal model for the reheater of a power plant boiler

    Energy Technology Data Exchange (ETDEWEB)

    Prieto, M.M. [Oviedo University, Energy Department, Campus de Viesques, 33204 GIJON. Asturias (Spain)]. E-mail: manuelap@uniovi.es; Suarez, I. [Oviedo University, Energy Department, Campus de Viesques, 33204 GIJON. Asturias (Spain); Fernandez, F.J. [Oviedo University, Energy Department, Campus de Viesques, 33204 GIJON. Asturias (Spain); Sanchez, H. [Central Termica de Soto de Ribera, Ribera de Arriba, Asturias (Spain); Mateos, M. [Central Termica de Soto de Ribera, Ribera de Arriba, Asturias (Spain)

    2007-02-15

    A three-dimensional numerical model for simulating flow and heat transfer in the reheater of a boiler is presented. The aim is to describe, as well as possible, the geometry of the reheater and to be able to perform different mass flows of steam along each of the tube serpentines. The model thus makes it possible to calculate the temperature of the tube surfaces along the reheater. The porosity concept is employed, along with empirical correlations for the convective heat transfer coefficient and the radiation heat transfer coefficients. The radiation equations consider most of the radiative effects of the gas: ash content, triatomic gases, type of fuel and temperatures, tube layout and distances and temperatures of other radiative surfaces. The model is proposed with a view to using the measured values of velocities, temperatures and gas composition in the reheater as boundary conditions. The equations are solved using a general purpose computational fluid dynamics (CFD) code in conjunction with specific calculations for the source terms.

  1. Differences in the composition of organic impurities in ground and surface waters. Consequences for the preparation of boiler feed water

    International Nuclear Information System (INIS)

    Huber, S.A.

    2002-01-01

    It is generally accepted that current limits for total organic carbon (TOC) in the pharmaceutical industry (500 ppb) and semiconductor industry (10-25 ppb) should be regarded as precautionary measures and do not necessarily reflect true scientific evidence. For the power industry the situation is different. Here, recommended TOC-limits for boiler feed waters (in 1999: VGB: 200 ppb; EPRI: 100 ppb) are based on scientific and empirical data. The oxidation of, say, 50 ppb TOC to carbon dioxide in the water/steam cycle will increase steam condensate conductivity by 0.48 μ S /cm (values may depend on literature source, here [1]), a value which is not acceptable as it desensitizes the detection of leaks in cooling water heat exchangers. Apart from this indirect effect of TOC there is also evidence for direct negative effects of TOC on steel materials. Even small amounts of organic acids, which are produced as intermediates in the TOC oxidation process, may locally lower the pH down to levels [2] where erosion corrosion of boiler tubes can take place. It was also found that carbon is enriched in stress corrosion cracks of turbine materials [3]. The present paper will discuss the ''TOC-issue'' in boiler feed water preparation. Most of the results can be applied also to other industries, e.g. semiconductor, chemical or pharmaceutical. (authors)

  2. Numerical analysis of flow instability in the water wall of a supercritical CFB boiler with annular furnace

    Science.gov (United States)

    Xie, Beibei; Yang, Dong; Xie, Haiyan; Nie, Xin; Liu, Wanyu

    2016-08-01

    In order to expand the study on flow instability of supercritical circulating fluidized bed (CFB) boiler, a new numerical computational model considering the heat storage of the tube wall metal was presented in this paper. The lumped parameter method was proposed for wall temperature calculation and the single channel model was adopted for the analysis of flow instability. Based on the time-domain method, a new numerical computational program suitable for the analysis of flow instability in the water wall of supercritical CFB boiler with annular furnace was established. To verify the code, calculation results were respectively compared with data of commercial software. According to the comparisons, the new code was proved to be reasonable and accurate for practical engineering application in analysis of flow instability. Based on the new program, the flow instability of supercritical CFB boiler with annular furnace was simulated by time-domain method. When 1.2 times heat load disturbance was applied on the loop, results showed that the inlet flow rate, outlet flow rate and wall temperature fluctuated with time eventually remained at constant values, suggesting that the hydrodynamic flow was stable. The results also showed that in the case of considering the heat storage, the flow in the water wall is easier to return to stable state than without considering heat storage.

  3. Fabrication of an improved tube-to-pipe header heat exchanger for the Fuel Failure Mockup (FFM) Facility

    International Nuclear Information System (INIS)

    Prislinger, J.J.; Jones, R.H.

    1977-05-01

    The procedure used in fabricating an improved tube-to-pipe header heat exchanger for the Fuel Failure Mockup (FFM) Facility is described. Superior performance is accomplished at reduced cost with adherence to the ASME Boiler and Pressure Vessel Code. The techniques used and the method of fabrication are described in detail

  4. Numerical simulation of a biomass fired grate boiler

    DEFF Research Database (Denmark)

    Yin, Chungen; Rosendahl, Lasse; Kær, Søren Knudsen

    2006-01-01

    Computational fluid dynamic (CFD) analysis of the thermal flow in the combustion furnace of a biomass-fired grate boiler provides crucial insight into the boiler's performance. Quite a few factors play important roles in a general CFD analysis, such as grid, models, discretization scheme and so on....... For a grate boiler, the modeling the interaction of the fuel bed and the gas phase above the bed is also essential. Much effort can be found in literature on developing bed models whose results are introduced into CFD simulations of freeboard as inlet conditions. This paper presents a CFD analysis...... of the largest biomass-fired grate boiler in Denmark. The focus of this paper is to study how significantly an accurate bed model can affect overall CFD results, i.e., how necessarily it is to develop an accurate bed model in terms of the reliability of CFD results. The ultimate purpose of the study is to obtain...

  5. Criteria of choosing building structures for rooftop boiler rooms

    Directory of Open Access Journals (Sweden)

    Plotnikov Artyom

    2018-01-01

    Full Text Available The paper investigates parameters of noise and vibration distribution in the territory of residential area depending on the structural materials and power of independent heat supply systems. Rooftop boiler rooms are decentralized heat supply systems in buildings. Today, residential areas are strongly affected by noise and vibrations. Adverse effects are isolated by buildings materials, protective shields and floating floors. Rooftop boiler rooms located in Tyumen city were investigated within this research. Structures of rooftop boiler rooms were analyzed. Acoustic analysis results and the parameters of equivalent continuous sound level are presented. An option for improvement of rooftop boiler rooms structures is suggested. Comparison of capital investments in construction and installation activities is carried out. Conclusion on capital investments required for noise protection is made.

  6. Emissions from Power Plant and Industrial Boiler Sector

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset provides hourly data on SO2, NOx, and CO2 emissions; gross load, steam load, and heat input; from electricity generation units and industrial boilers from...

  7. Knowledge based system for fouling assessment of power plant boiler

    International Nuclear Information System (INIS)

    Afgan, N.H.; He, X.; Carvalho, M.G.; Azevedo, J.L.T.

    1999-01-01

    The paper presents the design of an expert system for fouling assessment in power plant boilers. It is an on-line expert system based on selected criteria for the fouling assessment. Using criteria for fouling assessment based on 'clean' and 'not-clean' radiation heat flux measurements, the diagnostic variable are defined for the boiler heat transfer surface. The development of the prototype knowledge-based system for fouling assessment in power plants boiler comprise the integrations of the elements including knowledge base, inference procedure and prototype configuration. Demonstration of the prototype knowledge-based system for fouling assessment was performed on the Sines power plant. It is a 300 MW coal fired power plant. 12 fields are used with 3 on each side of boiler

  8. Numerical investigation of ash deposition in straw-fired boilers

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen

    in the design phase of straw-fired boilers. Some of the primary model outputs include improved heat transfer rate predictions and detailed information about local deposit formation rates. This information is essential when boiler availability and efficiency is to be estimated. A stand-alone program has been...... accumulation rates encountered during straw combustion in grate-fired boilers. The sub-models have been based on information about the combustion and deposition properties of straw gathered from the literature and combined into a single Computational Fluid Dynamics (CFD) based analysis tool which can aid...... transfer mechanisms have a pronounced influence on the combustion pattern. The combined set of sub-models has been evaluated using the straw-fired boiler at Masnedø CHP plant as a test case. The predicted grate combustion and KCl release patterns are in qualitative agreement with experimental findings...

  9. Boiler for combustion fuel in a fluidized bed

    Directory of Open Access Journals (Sweden)

    Laković Mirjana S.

    2015-01-01

    Full Text Available Fuel combustion in fluidized bed combustion is a process that is current and which every day gives more attention and there are many studies that have been closely associated with this technology. This combustion technology is widespread and constantly improving the range of benefits it provides primarily due to reduced emissions. This paper presents the boilers for combustion in a fluidized bed, whit characteristics and advantages. Also is shown the development of this type of boilers in Republic of Serbia. In this paper is explained the concept of fluidized bed combustion. Boilers for this type of combustion can be improved and thereby increase their efficiency level. More detailed characteristics are given for boilers with bubbling and circulating fluidized bed as well as their mutual comparison.

  10. Energy efficiency in boilers; Eficiencia energetica em caldeiras

    Energy Technology Data Exchange (ETDEWEB)

    Ponte, Ricardo Silva The [Universidade Federal do Ceara (UFCE), Fortaleza, CE (Brazil). Dept. de Engenharia Eletrica], email: ricthe@dee.ufc.br; Barbosa, Marcos Antonio Pinheiro; Rufino, Maria da Gracas [Universidade de Fortaleza (UNIFOR), CE (Brazil). Dept. de Engenharia Eletrica], emails: marcos_apb@unifor.br, gsrufino@unifor.br

    2010-07-01

    The boiler is vapor generator equipment that has been widely used in industrial milieu as in electric energy generation in thermoelectric plants. Since their first conception, the boilers have been changed in order to provide security and energetic efficiency. They can present high losses of energy if they don't be operated according to some criteria. A considerable part of boilers operation cost include fuel expenses. So, the adoption of effective steps in order to reduce fuel consumption is important to industry economy, besides it brings environmental benefits through the reduction of pollution liberation. The present article has the objective of emphasizing the effective steps for the economy of energy in boilers, such as, the regulation of combustion; the control of soot and incrustations; the installation of economizers, air heaters and super heaters; the reduction in purges and reintroduction of condensed steam. (author)

  11. Wood-Fired Boiler System Evaluation at Fort Stewart, GA

    National Research Council Canada - National Science Library

    Potts, Noel

    2002-01-01

    Part of the plan to modernize the central energy plant (CEP) at Fort Stewart, GA is focused on the installations wood-fired boiler, which provides steam for heating, cooling, and domestic hot water. The U.S...

  12. Seismic model of the nuclear boiler SPX2

    International Nuclear Information System (INIS)

    Christodoulou, K.

    1982-01-01

    A model of the nuclear boiler SPX2 is proposed in this paper enabling to carry out comparative calculations on the response to seismic effects. The calculations are made in CISE and SEPTEN departments of Electricite de France [fr

  13. Root cause analysis of oxide scale forming and shedding in high temperature reheater of a 200MW super high pressure boiler

    Science.gov (United States)

    Bo, Jiang; Hao, Weidong; Hu, Zhihong; Liu, Fuguo

    2015-12-01

    In order to solve the problem of over temperature tube-burst caused by oxide scale shedding and blocking tubes of high temperature reheater of a 200MW super high pressure power plant boiler, this paper expounds the mechanism of scale forming and shedding, and analyzes the probable causes of the tube-burst failure. The results show that the root cause of scale forming is that greater steam extraction flow after reforming of the second extraction leads to less steam flow into reheater, which causes over temperature to some of the heated tubes; and the root cause of scale shedding is that long term operation in AGC-R mode brings about great fluctuations of unit load, steam temperature and pressure, accelerating scale shedding. In conclusion, preventive measures are drawn up considering the operation mode of the unit.

  14. Bender/Coiler for Tubing

    Science.gov (United States)

    Stoltzfus, J. M.

    1983-01-01

    Easy-to-use tool makes coils of tubing. Tubing to be bend clamped with stop post. Die positioned snugly against tubing. Operator turns handle to slide die along tubing, pushing tubing into spiral groove on mandrel.

  15. [Emission characteristics of fine particles from grate firing boilers].

    Science.gov (United States)

    Wang, Shu-Xiao; Zhao, Xiu-Juan; Li, Xing-Hua; Wei, Wei; Hao, Ji-Ming

    2009-04-15

    Grate firing boilers are the main type of Chinese industrial boilers, which accounts for 85% of the industrial boilers and is one of the most important emission sources of primary air pollutants in China. In this study, five boilers in three cities were selected and tested to measure the emission characteristics of PM2.5, and gaseous pollutants were applied by a compact dilution sampling system, which was developed for this field study. Results showed that particles mass size distributions for the five industrial boilers presented single peak or double peak, former peaks near 0.14 microm and the later peaks after 1.0 microm; the cyclone dust remover and wet scrubber dust remover had effective removal efficiencies not only to PM2.5, but also to PM1.0; and under the condition of same control techniques, grate firing boiler with high capacity has less PM2.5 emission than the boiler with low capacity. In the PM2.5 collected from flue gases, SO4(2-) was the most abundant ion, accounted for 20%-40% of the PM2.5; and C was the most abundant element (7.5%-31.8%), followed by S (8.4%-18.7%). Carbon balance method was applied to calculate the emission factors of these pollutants. The emission factors of PM2.5, NO, and SO2 were in the range of 0.046-0.486 g x kg(-1), 1.63-2.47 g x kg(-1), 1.35-9.95 g x kg(-1) respectively. The results are useful for the emission inventory development of industrial boilers and the source analysis of PM2.5 in atmospheric environment.

  16. AUTOMATIC CONTROL SYSTEM OF THE DRUM BOILER SUPERHEATED STEAM TEMPERATURE.

    Directory of Open Access Journals (Sweden)

    Juravliov A.A.

    2006-04-01

    Full Text Available The control system of the temperature of the superheated steam of the drum boiler is examined. Main features of the system are the PI-controller in the external control loop and introduction of the functional component of the error signal of the external control loop with the negative feedback of the error signal between the prescribed value of steam flowrate and the signal of the steam flowrate in the exit of the boiler in the internal control loop.

  17. Brief introduction of GEF efficient industrial boiler project in China

    Energy Technology Data Exchange (ETDEWEB)

    Meijian, T.

    1996-12-31

    The present situation of installed industrial boilers, their efficiency and environmental impact are assessed. And the factors contribute to the low efficiency and serious pollution are summarized. Based on WB-assisted GEF project, {open_quotes}Efficient Industrial Boiler Project{close_quotes} aimed at CO{sub 2} mitigation in China, a series of effective measures to bring the GHG emission under control are addressed, in technology, system performance, and operation management aspects.

  18. The ASME Boiler and Pressure Vessel Code: overview

    International Nuclear Information System (INIS)

    Farr, J.R.

    1987-01-01

    To become familiar with the Boiler and Pressure Vessel Code of the American Society of Mechanical Engineers, it is necessary to understand the history, organization, and operation of the Boiler Code Committee as well as to become familiar with the important aspects of each Section of the Code. This chapter will review the background and contents of the Code as well as give a review of the salient contents of most sections. (author)

  19. Electric boilers for nuclear power plant in Liebstadt

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    A type of electric boiler, two of which are to be supplied to the Liebstadt nuclear power plant by Sulzer, is described. They are to be used for start-up and as reserve for the normal steam supply. The mode of operation is that feed water is sprayed into a high tension electrode such that the falling water conducts the current to the earthed electrode. This type of boiler presents advantages in space requrements and enviromental factors. (JIW)

  20. Electric boilers for nuclear power plant in Liebstadt

    Energy Technology Data Exchange (ETDEWEB)

    1977-11-29

    A type of electric boiler, two of which are to be supplied to the Liebstadt nuclear power plant by Sulzer, is described. They are to be used for start-up and as reserve for the normal steam supply. The mode of operation is that feedwater is sprayed into a high tension electrode such that the falling water conducts the current to the earthed electrode. This type of boiler presents advantages in space requrements and enviromental factors.

  1. Numerical modelling of a straw-fired grate boiler

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen

    2004-01-01

    The paper presents a computational fluid dynamics (CFD) analysis of a 33 MW straw-fired grate boiler. Combustion on the grate plays akey-role in the analysis of these boilers and in this work a stand-alone code was used to provide inlet conditions for the CFD analysis. Modelpredictions were compa...... mixing in the furnace is a key issue leading to these problems. q 2003 Elsevier Ltd. All rights reserved....

  2. Radiological pathways analysis for spent solvents from the boiler chemical cleaning at the Pickering Nuclear Site

    International Nuclear Information System (INIS)

    Garisto, N.C.; Eslami, Z.; Hodgins, S.; Beaman, T.; Von Svoboda, S.; Marczak, J.

    2006-01-01

    Spent solvents are generated as a result of Boiler Chemical Cleanings (BCC) at CANDU reactor sites. These solutions contain small amount of radioactivity from a number of different sources including: Cut tubes - short sections of boiler tubes are infrequently removed from the boilers for a detailed characterization. These tubes are typically only plugged at the tubesheet allowing the primary side deposits to be exposed to BCC solvents. Tube leaks - primary to secondary side leaks also occur infrequently as a result of tube degradation. Radioactivity from the leaking fluid can consequently be deposited in the sludge on the secondary side of the tubes. Diffusion of tritium - during normal operation of the reactor units, tritium slowly diffuses from the heavy water in the primary heat-transfer system to the light-water coolant on the secondary side. Some of this tritium is retained in the secondary side deposits. The Pickering Nuclear Generating Station (PNGS) would like the flexibility to have several options for handling the spent solvent waste and associated rinse water from BCC. To this end, a radiological pathways analysis was undertaken to determine dose consequences associated with each option. Sample results from this study are included in this paper. The pathways analysis is used in this study to calculate dose to hypothetical receptors including individuals such as truck drivers, incinerator workers, residue (ash) handlers, residents who live near the landfill, inadvertent intruders into the landfill after closure and residents who live near the outfall. This dose is compared to a de minimis dose. A de minimis dose or dose rate represents a level of risk, which is generally accepted as being of no significance. Shipments of spent solvents and rinse water with corresponding doses below de minimis can be sent to conventional (i.e., non-radioactive) landfills for incineration and disposal as the radioactive dose associated with them is much less than natural

  3. Fireside corrosion testing of candidate superheater tube alloys, coatings, and claddings -- Phase 2 field testing

    Energy Technology Data Exchange (ETDEWEB)

    Blough, J.L. [Foster Wheeler Development Corp., Livingston, NJ (United States)

    1996-08-01

    In Phase 1 of this project, a variety of developmental and commercial tubing alloys and claddings was exposed to laboratory fireside corrosion testing simulating a superheater or reheater in a coal-fired boiler. Phase 2 (in situ testing) has exposed samples of 347, RA85H, HR3C, 253MA, Fe{sub 3}Al + 5Cr, 310 modified, NF 709, 690 clad, and 671 clad for over 10,000 hours to the actual operating conditions of a 250-MW coal-fired boiler. The samples were installed on air-cooled, retractable corrosion probes, installed in the reheater cavity, controlled to the operating metal temperatures of an existing and advanced-cycle, coal-fired boiler. Samples of each alloy are being exposed for 4,000, 12,000, and 16,000 hours of operation. The present results are for the metallurgical examination of the corrosion probe samples after approximately 4,400 hours of exposure.

  4. Feasibility of recovery boiler in paper and pulp industry

    International Nuclear Information System (INIS)

    Rashid, H.

    2010-01-01

    in this paper feasibility of recovery boiler in terms of economics and environmental impacts in studied. Recovery boilers are employed in the pulp and paper industry where the cooking agent is recovered by burning black liquor. Cooking agent is exhausted due to the absorption of lignin (a burnable component) in cooking agent in the process of straw cooking. The process of recovery boiler is to remove lignin by combustion from black liquor, and heat is produced during the combustion of lignin which is used to produce steam. Recovery boiler is economical as it is recovering valuable chemicals and steam is produced as a byproduct. Steam from recovery boiler is also used for concentrating weak black liquor to concentrated black liquor recovering 50% of the utility water being used at the plant. The regenerated water in the form of foul condensate is reused in the process. The recovery of hazardous chemicals also reduces load of environmental pollution. Which otherwise can pollute the water reservoirs, and regeneration of water makes it environmentally friendly plant. Construction and challenges in operation of recovery boiler such as smelt-water explosion are also discussed in this paper. (author)

  5. 46 CFR 52.01-2 - Adoption of section I of the ASME Boiler and Pressure Vessel Code.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Adoption of section I of the ASME Boiler and Pressure...) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-2 Adoption of section I of the ASME Boiler and Pressure Vessel Code. (a) Main power boilers and auxiliary boilers shall be designed, constructed...

  6. Tube welding by the pulsed tig method

    International Nuclear Information System (INIS)

    Dick, N.T.

    1973-01-01

    During the construction of the helical wound boiler pods for the AGR stations at Hartlepool and Heysham, automatic TIG-welding techniques were used. In some cases limited access excluded the use of wire feed techniques and autogenous techniques had to be used. To resolve the problem of excessive concavity which occurred when using constant current autogenous techniques on 14.5 mm OD mild steel tubes of 1.8 mm thickness, pulsed-TIG welding was applied. By modifying the trailing edge of the pulse to produce a crater fill with each pulse, susceptibility to porosity and solidification cracking was reduced. The incorporation of digital counter permitted pulse duration, background duration, and electrode indexing distance to be monitored. (U.K.)

  7. DBSSP - A computer program for simulation of controlled circulation boiler and natural circulation boiler start up behavior

    International Nuclear Information System (INIS)

    Li Bin; Chen Tingkuan; Yang Dong

    2005-01-01

    In this paper, a computer program, Drum Boiler Start-up Simulation Program (DBSSP), is developed for simulating the start up behavior of controlled circulation and natural circulation boilers. The mathematical model developed here is based on the first principles of mass, energy and momentum conservations. In the boiler model, heat transfer in the waterwall, the superheater, the reheater and the economizer is simulated by the distributing parameter method, while heat transfer in the drum and the downcomer is simulated by lumped parameter analysis. The program can provide detailed flow and thermodynamic characteristics of the boiler components. The development of this program is based only on design data, so it can be used for any subcritical, controlled or natural circulation boiler. The simulation results were compared with experimental measurements, and good agreements between them were found. This program is expected to be useful for predicting the characteristics and the performance of controlled circulation and natural circulation boilers during the start up process. It also can be used to optimize a start up system for minimum start up time

  8. Orion Boiler Plate Airdrop Test System

    Science.gov (United States)

    Machin, Ricardo A.; Evans, Carol T.

    2013-01-01

    On the 29th of February 2012 the Orion Capsule Parachute Assembly System (CPAS) project attempted to perform an airdrop test of a boilerplate test article for the second time. The first attempt (Cluster Development Test 2, July 2008) to deliver a similar boilerplate from a C-17 using the Low Velocity Air Drop (LVAD) technique resulted in the programmer parachute failing to properly inflate, the test article failing to achieve the desired test initiation conditions, and the test article a total loss. This paper will pick up where the CDT-2 failure investigation left off, describing the test technique that was adopted, and outline the modeling that was performed to gain confidence that the second attempt would be successful. The second boiler plate test (Cluster Development Test 3-3) was indeed a complete success and has subsequently been repeated several times, allowing the CPAS project to proceed with the full scale system level development testing required to integrate the hardware to the first Entry Flight Test vehicle as well as go into the Critical Design Review with minimum risk and a mature design.

  9. Computations of NOx emissions of domestic boilers

    Energy Technology Data Exchange (ETDEWEB)

    Thevenin, D. [Ecole Centrale de Paris, 92 - Chatenay-Malabry (France). EM2C Lab.; Gicquel, O.; Darabiha, N.

    2001-07-01

    Due to severe regulations concerning pollutant emissions, practical devices using combustion to release energy must be designed from the start using accurate, predictive numerical tools. A partially premixed methane/air flame in a two-dimensional configuration is investigated in this work. This configuration is close to those used in real domestic gas boilers. The flame structure and flow pattern are calculated using complex chemistry and detailed transport models. A post-processing method is then used to predict NO emission. Computations are performed for two configurations. The two cases have the same primary and secondary mass flow-rates and equivalence ratio. The only difference between them is the introduction of an insert inside the primary injector. Both results have been compared to measurements. Calculations are found to be in good agreement with the flame shapes observed experimentally. The classical burner shows a Bunsen-type flame while the one with an insert has a totally different shape (butterfly-type flame). NO emission levels are also well predicted in both configurations. The butterfly flame induces a reduction in NO emission. This reduction seems to be due to the increased mixing between the burnt gases and the secondary air jet, which homogenizes the temperature distribution and reduces the maximum temperature. (orig.)

  10. Model-free adaptive control of supercritical circulating fluidized-bed boilers

    Science.gov (United States)

    Cheng, George Shu-Xing; Mulkey, Steven L

    2014-12-16

    A novel 3-Input-3-Output (3.times.3) Fuel-Air Ratio Model-Free Adaptive (MFA) controller is introduced, which can effectively control key process variables including Bed Temperature, Excess O2, and Furnace Negative Pressure of combustion processes of advanced boilers. A novel 7-input-7-output (7.times.7) MFA control system is also described for controlling a combined 3-Input-3-Output (3.times.3) process of Boiler-Turbine-Generator (BTG) units and a 5.times.5 CFB combustion process of advanced boilers. Those boilers include Circulating Fluidized-Bed (CFB) Boilers and Once-Through Supercritical Circulating Fluidized-Bed (OTSC CFB) Boilers.

  11. Performance of a pellet boiler fired with agricultural fuels

    International Nuclear Information System (INIS)

    Carvalho, Lara; Wopienka, Elisabeth; Pointner, Christian; Lundgren, Joakim; Verma, Vijay Kumar; Haslinger, Walter; Schmidl, Christoph

    2013-01-01

    Highlights: ► Performance evaluation of a pellet boiler operated with different agricultural fuels. ► Agricultural fuels could be burn in the tested boiler for a certain period of time. ► All the fuels (except straw and Sorghum) satisfied the European legal requirements. ► Boilers for burning agricultural fuels should have a flexible control system. - Abstract: The increasing demand for woody biomass increases the price of this limited resource, motivating the growing interest in using woody materials of lower quality as well as non-woody biomass fuels for heat production in Europe. The challenges in using non-woody biomass as fuels are related to the variability of the chemical composition and in certain fuel properties that may induce problems during combustion. The objective of this work has been to evaluate the technical and environmental performance of a 15 kW pellet boiler when operated with different pelletized biomass fuels, namely straw (Triticum aestivum), Miscanthus (Miscanthus × giganteus), maize (Zea mays), wheat bran, vineyard pruning (from Vitis vinifera), hay, Sorghum (Sorghum bicolor) and wood (from Picea abies) with 5% rye flour. The gaseous and dust emissions as well as the boiler efficiency were investigated and compared with the legal requirements defined in the FprEN 303-5 (final draft of the European standard 303-5). It was found that the boiler control should be improved to better adapt the combustion conditions to the different properties of the agricultural fuels. Additionally, there is a need for a frequent cleaning of the heat exchangers in boilers operated with agricultural fuels to avoid efficiency drops after short term operation. All the agricultural fuels satisfied the legal requirements defined in the FprEN 303-5, with the exception of dust emissions during combustion of straw and Sorghum. Miscanthus and vineyard pruning were the best fuels tested showing comparable emission values to wood combustion

  12. Ultra-Supercritical Pressure CFB Boiler Conceptual Design Study

    Energy Technology Data Exchange (ETDEWEB)

    Zhen Fan; Steve Goidich; Archie Robertson; Song Wu

    2006-06-30

    Electric utility interest in supercritical pressure steam cycles has revived in the United States after waning in the 1980s. Since supercritical cycles yield higher plant efficiencies than subcritical plants along with a proportional reduction in traditional stack gas pollutants and CO{sub 2} release rates, the interest is to pursue even more advanced steam conditions. The advantages of supercritical (SC) and ultra supercritical (USC) pressure steam conditions have been demonstrated in the high gas temperature, high heat flux environment of large pulverized coal-fired (PC) boilers. Interest in circulating fluidized bed (CFB) combustion, as an alternative to PC combustion, has been steadily increasing. Although CFB boilers as large as 300 MWe are now in operation, they are drum type, subcritical pressure units. With their sizes being much smaller than and their combustion temperatures much lower than those of PC boilers (300 MWe versus 1,000 MWe and 1600 F versus 3500 F), a conceptual design study was conducted herein to investigate the technical feasibility and economics of USC CFB boilers. The conceptual study was conducted at 400 MWe and 800 MWe nominal plant sizes with high sulfur Illinois No. 6 coal used as the fuel. The USC CFB plants had higher heating value efficiencies of 40.6 and 41.3 percent respectively and their CFB boilers, which reflect conventional design practices, can be built without the need for an R&D effort. Assuming construction at a generic Ohio River Valley site with union labor, total plant costs in January 2006 dollars were estimated to be $1,551/kW and $1,244/kW with costs of electricity of $52.21/MWhr and $44.08/MWhr, respectively. Based on the above, this study has shown that large USC CFB boilers are feasible and that they can operate with performance and costs that are competitive with comparable USC PC boilers.

  13. Thermomechanical CSM analysis of a superheater tube in transient state

    Science.gov (United States)

    Taler, Dawid; Madejski, Paweł

    2011-12-01

    The paper presents a thermomechanical computational solid mechanics analysis (CSM) of a pipe "double omega", used in the steam superheaters in circulating fluidized bed (CFB) boilers. The complex cross-section shape of the "double omega" tubes requires more precise analysis in order to prevent from failure as a result of the excessive temperature and thermal stresses. The results have been obtained using the finite volume method for transient state of superheater. The calculation was carried out for the section of pipe made of low-alloy steel.

  14. Experimental study on dew point corrosion characteristics of the heating surface in a 65 t/h biomass-fired circulating fluidized bed boiler

    International Nuclear Information System (INIS)

    Wang, Yungang; Ma, Haidong; Liang, Zhiyuan; Chen, Heng; Zhao, Qinxin; Jin, Xin

    2016-01-01

    Highlights: • Dew point corrosion and ash deposit tests in a biomass-fired boiler were performed. • The XRD, XRF and SEM methods were used to analyze corrosion samples. • The deposits were made up of ash deposit layer, coupling layer and corrosion layer. • The metal matrix simultaneously confronted chlorine corrosion and oxygen corrosion. - Abstract: The dew point corrosion characteristics of the heating surface in a 65 t/h biomass-fired circulating fluidized bed (CFB) boiler were experimentally studied. The cross-sectional morphology and composition of the ash deposition were analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD) and X-ray fluorescence spectrum (XRF), respectively. The results showed that the test tube surface was covered by ash deposit layer, coupling layer and corrosion layer. The ash deposit layer and the coupling layer were prone to spall off together. The coupling layer consists of partial ash and corrosion products. The corrosion layer was mainly composed of chlorides (FeCl_3, FeCl_2, and FeOCl) and oxides (FeOOH, Fe_2O_3). With the increase of the tube wall temperature, the corrosion depth decreased dramatically and the dew point corrosion was alleviated efficiently. The metal matrix simultaneously suffered from chlorine corrosion and oxygen corrosion. As the tube wall temperature was above water dew point, the main corrosion mode was oxygen corrosion. As the tube wall temperature was below water dew point, the main corrosion mode was chlorine corrosion.

  15. Process for start-up and slack period operation of fully charged boilers, e. g. of coal pressure gasification plants, and boiler system to carry out the process

    Energy Technology Data Exchange (ETDEWEB)

    Meyer-Kahrweg, H

    1978-10-19

    For the start-up and slack period of fully charged boilers hot water of e.g. 180/sup 0/C from a high pressure heater which is fed by a start-up boiler is used. In the first instance the boiler, its preheater and the vaporizer are filled with hot water from the start-up boiler until a medium water level is obtained. Subsequently water from the water separator is recycled through the preheater and the boiler by forced circulation and it is heated up to the hot water temperature by the start-up boiler. After the desired temperature has been reached the pressure combustion is ignited and the circulation through the preheater is interrupted by reversing to direct feed back. A considerable shortening of the start-up time is achieved because no heat is released to the condensation water in the boiler system as is done usually.

  16. X-ray tubes

    International Nuclear Information System (INIS)

    Young, R.W.

    1979-01-01

    A form of x-ray tube is described which provides satisfactory focussing of the electron beam when the beam extends for several feet from gun to target. Such a tube can be used for computerised tomographic scanning. (UK)

  17. Pressure tube type reactors

    International Nuclear Information System (INIS)

    Komada, Masaoki.

    1981-01-01

    Purpose: To increase the safety of pressure tube type reactors by providing an additional ECCS system to an ordinary ECCS system and injecting heavy water in the reactor core tank into pressure tubes upon fractures of the tubes. Constitution: Upon fractures of pressure tubes, reduction of the pressure in the fractured tubes to the atmospheric pressure in confirmed and the electromagnetic valve is operated to completely isolate the pressure tubes from the fractured portion. Then, the heavy water in the reactor core tank flows into and spontaneously recycles through the pressure tubes to cool the fuels in the tube to prevent their meltdown. By additionally providing the separate ECCS system to the ordinary ECCS system, fuels can be cooled upon loss of coolant accidents to improve the safety of the reactors. (Moriyama, K.)

  18. Gastrostomy feeding tube - bolus

    Science.gov (United States)

    Feeding - gastrostomy tube - bolus; G-tube - bolus; Gastrostomy button - bolus; Bard Button - bolus; MIC-KEY - bolus ... KEY, 3 to 8 weeks after surgery. These feedings will help your child grow strong and healthy. ...

  19. Feeding tube insertion - gastrostomy

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002937.htm Feeding tube insertion - gastrostomy To use the sharing features on this page, please enable JavaScript. A gastrostomy feeding tube insertion is the placement of a feeding ...

  20. Neural Tube Defects

    Science.gov (United States)

    Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the ... that she is pregnant. The two most common neural tube defects are spina bifida and anencephaly. In ...