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.

Recovery Act: Oxy-Combustion Technology Development for Industrial-Scale Boiler Applications. Task 4 - Testing in Alstom's 15 MW_th Boiler Simulation Facility

Energy Technology Data Exchange (ETDEWEB)

Levasseur, Armand

2014-04-30

Alstom Power Inc. (Alstom), under U.S. DOE/NETL Cooperative Agreement No. DE-NT0005290, is conducting a development program to generate detailed technical information needed for application of oxy-combustion technology. The program is designed to provide the necessary information and understanding for the next step of large-scale commercial demonstration of oxy combustion in tangentially fired boilers and to accelerate the commercialization of this technology. The main project objectives include: Design and develop an innovative oxyfuel system for existing tangentially-fired boiler units that minimizes overall capital investment and operating costs; Evaluate performance of oxyfuel tangentially fired boiler systems in pilot scale tests at Alstom’s 15 MWth tangentially fired Boiler Simulation Facility (BSF); Address technical gaps for the design of oxyfuel commercial utility boilers by focused testing and improvement of engineering and simulation tools; Develop the design, performance and costs for a demonstration scale oxyfuel boiler and auxiliary systems; Develop the design and costs for both industrial and utility commercial scale reference oxyfuel boilers and auxiliary systems that are optimized for overall plant performance and cost; and, Define key design considerations and develop general guidelines for application of results to utility and different industrial applications. The project was initiated in October 2008 and the scope extended in 2010 under an ARRA award. The project is scheduled for completion by April 30, 2014. Central to the project is 15 MWth testing in the BSF, which provided in-depth understanding of oxy-combustion under boiler conditions, detailed data for improvement of design tools, and key information for application to commercial scale oxy-fired boiler design. Eight comprehensive 15 MWth oxy-fired test campaigns were performed with different coals, providing detailed data on combustion, emissions, and thermal behavior over a matrix of

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.

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...

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.

Development and test of small-scale batch-fired straw boilers in Denmark

International Nuclear Information System (INIS)

Kristensen, E.F.; Kristensen, J.K.

2004-01-01

In Denmark, government subsidies for the testing and installation of biomass-fired boilers were available for the period from 1995 until 2002. Each boiler type had to pass an official approval test to achieve subsidy. The combustion abilities of the boiler were optimized prior to the test. The main aim of this subsidy was to encourage the development of energy-efficient and environmentally friendly boilers. The scheme was therefore organized in such a way that the greatest subsidies were awarded for boilers with high efficiency and low emissions. This goal has in effect been achieved for batch-fired straw boilers, where the typical efficiency has been increased from about 75% in 1995 to about 87% in 2002. Similarly, the carbon monoxide emissions have been reduced from 5000 ppm (reference value 10% O 2 ) in 1995 to less than 1000 ppm in 2002. These improvements are mainly due to better insulation inside the combustion chamber, more efficient techniques for supplying air to the combustion process, improved cooling of the flue gas, and optimization of the electronic control unit for the air supply

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.

Development of AZS refractories for the glass industry

International Nuclear Information System (INIS)

Guzman, A.M.; Rodriguez, P.

2004-01-01

Refractory materials can support high temperatures, thermal strength and the contact with aggressive environments, for this reason they are widely used in the cement, glass and steel industry. Commercial AZS (alumina-zirconia-silica) refractories are a good alternative in refractory materials for the glass industry' because they can support the aggressive conditions during liquid processing of glass. However, another problem encountered in glass industry is contamination by refractory' material that fall into the molten glass, which can produce a series of defects in the final product. This research was conducted to develop new formulations of AZS refractories with different amounts of ZrO 2 with the purpose of improving the characteristics, properties and the work conditions in the glass melting furnaces and, at the same time, lower the costs this type of refractories. The results obtained indicate that the composition with low content of ZrO 2 can provide better properties than the commercial product, with some modifications in the particle size distribution. Copyright (2004) AD-TECH - International Foundation for the Advancement of Technology Ltd

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.

Development of an Optimizing Control Concept for Fossil-Fired Boilers using a Simulation Model

DEFF Research Database (Denmark)

Mortensen, J. H.; Mølbak, T.; Commisso, M.B.

1997-01-01

of implementation and commissioning. The optimizing control system takes into account the multivariable and nonlinear characteristics of the boiler process as a gain-scheduled LQG-controller is utilized. For the purpose of facilitating the control concept development a dynamic simulation model of the boiler process......An optimizing control system for improving the load following capabilities of power plant units has been developed. The system is implemented as a complement producing additive control signals to the existing boiler control system, a concept which has various practical advantages in terms...... model when designing a new control concept are discussed....

Development of alumino-silicate refractories in Ghana

International Nuclear Information System (INIS)

Kisiedu, A. K.; Tetteh, D.M.B.; Obiri, H. A.; Brenya, E. F.; Ayensu, A.

2008-01-01

Alumino-silicate (bauxite), andalusite, kaolin and clay were investigated for suitability in production of alumina, mullite and fireclay brick refractories. The raw materials were characterized by X-ray diffraction, differential thermal and silicate analyses. The x-ray diffraction analysis of alumina and mullite refractories fired at 1450 0 C, and fireclay bricks fired at 1350 0 C, indicated presence of corundum and alpha-alumina crystals. The values of thermal (fired) shrinkage, crushing, strength, porosity, water absorption and bulk density determined were 31.1%, 2.3 x 10 3 kg/m 3 , 4.86 x 10 6 N/m 2 and 13.2 % for mullite; 30.2%, 2.4 x 10 3 kg/m 3 , 3.20 x 10 6 N/m 2 and W = 12.8 % for alumina; and 25.2 %, 2.1 x 10 3 kg/m 3 , 2.61 x 10 6 N/m 2 and W = 11.8% for fireclay, respectively. Bauxite, andalusite and special kaolin were identified as potential raw materials for developing alumina and mullite refractories for construction of high temperature kilns and furnaces operating at 1350 0 C. The clay and kaolin minerals could be used to produce fireclay refractories for construction of incinerators operating at maximum temperatures of about 1000 0 C. The performance of the refractories was demonstrated by producing bricks to construct kilns and incinerators for the ceramic industry and hospitals. (au)

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)

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.

Respiratory assessment of refractory ceramic fibers in a heating technician population.

Science.gov (United States)

Lucas, David; Clamagirand, Vincent; Capellmann, Pascale; Hervé, Agnès; Mauguen, Gilles; Le Mer, Yannik; Jegaden, Dominique

2018-04-01

Refractory ceramic fibers (RCF) have been extensively used for insulation in condensing boilers. The aim of this study was to evaluate the respiratory exposure to these fibers among maintenance heating technicians. We first created a working group (Carsat Brittany and Finistère Occupational Health Services) and carried out a sampling strategy. Atmospheric measurements were done during work tasks, and filters were analyzed by phase contrast microscopy (PCM) and scanning electron microscopy (SEM) in French approved laboratories. Four companies were included for a total of 15 days of work. During those 15 workdays, 12 SEM and 21 PCM samples were taken and analyzed. The phase contrast microscopy and SEM average results were 0.04 and 0.004 fibers/cm 3 , respectively. In conclusion, the study confirms heating technician RCF respiratory exposure during maintenance work for both condensation gas boilers and atmospheric boilers. Collective and individual prevention measures should be implemented along with appropriate medical follow-up.

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)

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...

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

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)

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)

Research, Development and Demonstration of Bio-Mass Boiler for Food Industry

Energy Technology Data Exchange (ETDEWEB)

Fisher, Steve [Burns & McDonnell, Inc., Kansas City, MO (United States); Knapp, David [Burns & McDonnell, Inc., Kansas City, MO (United States)

2012-07-01

Frito-Lay is working to reduce carbon emissions from their manufacturing plants. As part of this effort, they invested in a biomass-fired boiler at the Topeka, Kansas, plant. Frito-Lay partnered with Burns & McDonnell Engineering, Inc. and CPL Systems, Inc., to design and construct a steam producing boiler using carbon neutral fuels such as wood wastes (e.g. tree bark), shipping pallets, and used rubber vehicle tires. The U.S. Department of Energy (DOE) joined with Frito-Lay, Burns & McDonnell, and CPL to analyze the reductions in carbon dioxide (CO₂) emissions that result from use of biomass-fired boilers in the food manufacturing environment. DOE support provided for the data collection and analysis, and reporting necessary to evaluate boiler efficiencies and reductions in CO₂ emissions. The Frito-Lay biomass-fired boiler has resulted in significant reductions in CO₂ emissions from the Topeka production facility. The use of natural gas has been reduced by 400 to 420 million standard cubic feet per year with corresponding reductions of 24,000 to 25,000 tons of CO₂. The boiler does require auxiliary functions, however, that are unnecessary for a gas-fired boiler. These include heavy motors and fans for moving fuel and firing the boiler, trucks and equipment for delivering the fuel and moving at the boiler plant, and chippers for preparing the fuel prior to delivery. Each of these operations requires the combustion of fossil fuels or electricity and has associated CO₂ emissions. Even after accounting for each of these auxiliary processes, however, the biomass-fired boiler results in net emission reductions of 22,500 to 23,500 tons of CO₂ per year.

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)

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.

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...

Data for modern boilers used in co-combustion; Moderna panndata inom samfoerbraenning

Energy Technology Data Exchange (ETDEWEB)

Thorson, Ola [S.E.P. Scandinavian Energy Project AB, Goeteborg (Sweden)

2004-04-01

This project is a survey and a description of today's technical status and future development trends in the field of co-combustion. The survey is done from an energy production company's point of view and two technical questions have been studied; the possibilities for high steam data and the possibilities for a wide load range. These parameters are limited by the corrosive properties of the fuel and the environmental requirements in the EU directive for combustion of waste. In the report following issues are discussed: Examples of and experiences from co-combustion plants and plants that combust problematic fuels and have high steam data. A future prospect of high steam data in co-combustion plants by the usage of modern technical solutions and a description of these solutions. Important research and development results from combustion of problematic fuels in combination with high steam data. Choice of firing technology, boiler design and auxiliary systems and its affection on the load range in a boiler for co-combustion. A literature survey has been done to get the latest results from combustion of problematic fuels. Then a number of interesting plants have been identified and facts about them have been collected by contacts with plant owners, suppliers and professional researchers and also through publications. The report shows that Sweden, Finland and Denmark are in the front line of using high steam data for co-combustion of biomass and waste fuels. There are/have been problems with superheater corrosion in many of these plants but a number of ways how to handle high steam data have been identified: Adjust the fuel mix or add additives; Use high alloy materials; Consider the final super heater as a part that is worn out by time; Place the final super heater in the particle loop seal/sand locker; Use an external separate fired super heater; Gasification and then co-combustion of the pyrolysis gas in a conventional existing boiler; Place the

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.

Development of refractory concrete for extreme conditions

International Nuclear Information System (INIS)

Pundiene, I; Antonovich, V; Stonys, R; Demidova-Buiziniene, I

2011-01-01

Comparative analysis is provided for the properties of medium-cement refractory concrete with microsilica based on mullite filler in relation to different type of deflocculant. The effect of different deflocculants on refractory concrete structure formation, hydration, rheology, strength and heat resistance is discussed. Corrosion resistance test, determined that samples with hybrid deflocculant showed better resistance for slag penetration than samples with only the sodium tripolyphosphate or polycarboxylate ether deflocculant. Moreover, a composition of hybrid deflocculant let to control the rate of the hydration process and to get features of refractory refractory concrete.

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.

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.

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.)

Report on research results of the development of high efficient boilers in fiscal 1996. Research development of high efficient industrial furnaces, etc; Koseino boiler no kaihatsu ni kansuru kenkyu seika hokokusho. Koseino kogyoro nado ni kansuru kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

Out of the developments of high efficient boilers which have been continued since fiscal 1993, the paper reported the result of the development conducted in fiscal 1996. The oxygen combustion (the oxygen enrichment combustion including 100% oxygen combustion) decreases the amount of flue gas and reduces heat loss of the flue gas, and is also effective as NOx reduction measures. The experiment was conducted using testing furnace. The boiler efficiency rapidly increased with the increasing concentration of oxygen enrichment. In the pure oxygen combustion, the overall boiler efficiency of a 106% level (low heating value standard) is expected. Since the boiler wet flue gas is decreased, the NOx emission is reduced. The boiler can raise the combustion temperature with no fear of NOx and can be reduced in size. CO2 decreases in proportion to the energy saving effect. The development of a condensation flue gas heat exchanger is aimed at recovering heat down to the low temperature. Prediction of heat transfer in the steam condensation region becomes possible, and the size reduction can be expected. Dew point corrosion resistant materials were also selected. As to the high speed combustion control, a simple type using micro-processor was developed. Obtained were high speed, compactness, electric power saving, and high controllability. 14 refs., 306 figs., 88 tabs.

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...

REFRACTORY FOR BLACK LIQUOR GASIFIERS

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr.; Alireza Rezaie

2003-12-01

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

Refractory for Black Liquor Gasifiers

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr; Alireza Rezaie

2003-12-01

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LFHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

Refractory for Black Liquor Gasifiers

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr; Alireza Rezaie; Xiaoting Liang; Musa Karakus; Jun Wei

2005-12-01

The University of Missouri-Rolla identified materials that permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project was to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study attempted to define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials were selected or developed that reacted with the gasifier environment to form protective surfaces in

Refractory for Black Liquor Gasifiers

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr; Musa Karakus; Xiaoting Liang

2005-10-01

The University of Missouri-Rolla identified materials that permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project was to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study attempted to define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials were selected/developed that either react with the gasifier environment to form protective surfaces in

Refractory for Black Liquor Gasifiers

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick; Musa Karakus; Alireza Rezaie

2004-03-30

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

REFRACTORY FOR BLACK LIQUOR GASIFIERS

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Alireza Rezaie

2004-07-01

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

REFRACTORY FOR BLACK LIQUOR GASIFIERS

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Alireza Rezaie

2004-10-01

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

REFRACTORY FOR BLACK LIQUOR GASIFIERS

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Jun Wei

2005-01-01

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

REFRACTORY FOR BLACK LIQUOR GASIFIERS

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr; Musa Karakus; Xiaoting Liang; Jun Wei

2005-04-01

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

REFRACTORY FOR BLACK LIQUOR GASIFIERS

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr; Musa Karakus; Xiaoting Liang

2005-07-01

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

REFRACTORY FOR BLACK LIQUOR GASIFIERS

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr.; Alireza Rezaie

2004-04-01

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the materials problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

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.

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

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...

Development of Cost Effective Oxy-Combustion Retrofitting for Coal-Fired Boilers

Energy Technology Data Exchange (ETDEWEB)

Hamid Farzan

2010-12-31

The overall objective of this project is to further develop the oxy-combustion technology for commercial retrofit in existing wall-fired and Cyclone boilers by 2012. To meet this goal, a research project was conducted that included pilot-scale testing and a full-scale engineering and economic analysis.

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.

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.

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.

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.

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.

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)

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

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)

Refractory for Black Liquor Gasifiers

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr; Musa Karakus; Xiaoting Laing

2005-10-01

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

Boiler recirculation pumps for nuclear power stations - present state of development. Directions for planning, operational experience

International Nuclear Information System (INIS)

Mattias, H.B.

1976-01-01

Boiler recirculation pumps are important components of modern power stations. The development of large recirculation pumps up to a driving power of 1,500 kW was faced with some problems in meeting the plant requirements. In this paper, the present state of development is dealt with. The development problems in the fields of hydrodynamics, cavitation, corrosion and erosion are dealt with as well as the problems of the design of the casing with regard to thermodynamics and strength. Finally, operational experience with the boiler recirculation pump for 600 MW power stations will be reported on. (orig./AK) [de

Mechanical and Physicochemical Evaluation of Alkaleri Fireclay for Refractory Application

Directory of Open Access Journals (Sweden)

Job Ajala Amkpa

2017-04-01

Full Text Available The mechanical, chemical and physical property of Alkaleri fireclay was investigated for its appropriateness for refractory application. The chemical composition was performed and analyzed using the X-ray fluorescence (XRF spectrometer Bench top XRF analyzer technique. Chemical property result indicated that the clay contained 67.4 % silica (SiO2, 30.06 % aluminum (Al2O3, and other impurities. The clay was subjected to mechanical activation through sintering process at varied sintering temperatures of 900 °C, 1000 °C, 1100 °C and 1200 °C. At the best sintering temperature of 1200 °C, the cold crushing strength (CCS was 17.82 MPa, in the physical properties; apparent porosity was 22.8 %, bulk density was 1.8 g/cm3, and firing shrinkage was 8.9 %. The Alkaleri clay belongs to alumino-silicate fireclay group and therefore, suitable materials for refractory application of ladle, kiln dryer, boilers, cook stoves, furnace lining and bricks.

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)

REFRACTORY FOR BLACK LIQUOR GASIFIERS

Energy Technology Data Exchange (ETDEWEB)

William L. Headrick Jr; Musa Karakus; Jun Wei

2005-03-01

The University of Missouri-Rolla will identify materials that will permit the safe, reliable and economical operation of combined cycle gasifiers by the pulp and paper industry. The primary emphasis of this project will be to resolve the material problems encountered during the operation of low-pressure high-temperature (LPHT) and low-pressure low-temperature (LPLT) gasifiers while simultaneously understanding the materials barriers to the successful demonstration of high-pressure high-temperature (HPHT) black liquor gasifiers. This study will define the chemical, thermal and physical conditions in current and proposed gasifier designs and then modify existing materials and develop new materials to successfully meet the formidable material challenges. Resolving the material challenges of black liquor gasification combined cycle technology will provide energy, environmental, and economic benefits that include higher thermal efficiencies, up to three times greater electrical output per unit of fuel, and lower emissions. In the near term, adoption of this technology will allow the pulp and paper industry greater capital effectiveness and flexibility, as gasifiers are added to increase mill capacity. In the long term, combined-cycle gasification will lessen the industry's environmental impact while increasing its potential for energy production, allowing the production of all the mill's heat and power needs along with surplus electricity being returned to the grid. An added benefit will be the potential elimination of the possibility of smelt-water explosions, which constitute an important safety concern wherever conventional Tomlinson recovery boilers are operated. Developing cost-effective materials with improved performance in gasifier environments may be the best answer to the material challenges presented by black liquor gasification. Refractory materials may be selected/developed that either react with the gasifier environment to form protective

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

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.

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

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

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...

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...

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...

A statistical estimator for the boiler power and its related parameters

International Nuclear Information System (INIS)

Tang, H.

2001-01-01

To determine the boiler power accurately is important for both controlling the plant and maximizing the plant productivity. There are two computed boiler powers for each boiler. They are steam based boiler power and feedwater based boiler power. The steam based boiler power is computed as the enthalpy difference between the feedwater enthalpy and the boiler steam enthalpy. The feedwater based boiler power is computed as enthalpy absorbed by the feedwater. The steam based boiler power is computed in RRS program and used in calibrating the measured reactor power, while the feedwater based boiler power is computed in CSTAT program and used for indication. Since the steam based boiler power is used as feedback in the reactor control, it is chosen to be the one estimated in this work. Because the boiler power employs steam flow, feedwater flow and feedwater temperature measurements, and because any measurement contains constant or drifting noise and bias, the reconciliation and rectification procedures are needed to determine the boiler power more accurately. A statistic estimator is developed to perform the function of data reconciliation, gross error detection and instruments performance monitoring

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

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...

Development of industrial x-ray computed tomography and its application to refractories

International Nuclear Information System (INIS)

Aiba, Yoshiro; Oki, Kazuo; Nakamura, Shigeo; Fujii, Masashi.

1985-01-01

An industrial X-ray computed tomography was developed under the influence of the rapid spread of the use of the X-ray CT scanner in the medical field and improvements of the equipment. Although current nondestructive testing machines of refractories use the ultrasonic inspection method or the X-ray fluoroscopic method, these equipments cannot produce a tomogram or cannot carry out quantitative evaluation. By using an industrial X-ray computed tomography, submerged nozzles for continuous casting of steel were analyzed with interesting results. The features of the industrial X-ray computed tomography applied for refractory nozzles are as follows: (1) It promptly detects interior defects. (2) It can measure dimensions and shapes. (3) It can numerically express the distribution of density. Accordingly, it is expected that the industrial X-ray computed tomography will widely be used in the fields of development and quality control of refractories and advanced ceramic materials. (author)

Development of electro fused aggregates for use in refractories for the burning zone of cement kilns

International Nuclear Information System (INIS)

Ferreira, Luis Leonardo Horne Curimbaba

2006-01-01

Electro fused aggregates are largely used in refractory production due to the better performance reached when they are employed. In this work electro fused aggregates were designed for application in refractories for the burning zone of cement kilns. Initially reaction evaluation was conducted aiming the identification of the most prone refractory systems when single refractory phases react with Portland cement phases at high temperatures. In the next step, raw materials of the best refractory systems were electro fused to generate different aggregate compositions. The electro fused aggregates properties were evaluated and the classified ones were used to produce refractory bricks for the burning zone of cement kilns. General characteristics of these bricks were measured and compared with a standard magnesia-spinel refractory. Aggregates of the system Mg O - TiO 2 - Ca O, more specifically aggregates belonged to the compatibility triangle Mg O - Mg 2 TiO 4 - CaTiO 3 , showed suitable characteristics for development of refractories for the burning zone cement kilns. (author)

Developing the optimum boiler water and feedwater treatment for fossil plants

Energy Technology Data Exchange (ETDEWEB)

Dooley, B [Electric Power Research Inst., Palo Alto, California (United States)

1996-12-01

Over the last two years a new set of cycle chemistry guidelines has been developed for each of the treatments used in fossil plants. These revisions have been based on research conducted over the last ten years, much at the international collaborative level. By careful selection and optimization of the boiler water and feedwater treatments, it will be possible to accrue large financial, maintenance, availability and performance improvements. (au) 14 refs.

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....

Black liquor combustion validated recovery boiler modeling, five-year report

Energy Technology Data Exchange (ETDEWEB)

Grace, T.M.; Frederick, W.J.; Salcudean, M.; Wessel, R.A.

1996-08-01

The objective of this project was to develop a new computer model of a recovery boiler furnace using a computational fluid dynamics (CFD) code specifically tailored to the requirements for solving recovery boiler flows, and using improved submodels for black liquor combustion based on continued laboratory fundamental studies. The project originated in October 1990 and was scheduled to run for four years. At that time, there was considerable emphasis on developing accurate predictions of the physical carryover of macroscopic particles of partially burnt black liquor and smelt droplets out of the furnace, since this was seen as the main cause of boiler plugging. This placed a major emphasis on gas flow patterns within the furnace and on the mass loss rates and swelling and shrinking rates of burning black liquor drops. As work proceeded on developing the recovery boiler furnace model, it became apparent that some recovery boilers encounter serious plugging problems even when physical carryover was minimal. After the original four-year period was completed, the project was extended to address this issue. The objective of the extended project was to improve the utility of the models by including the black liquor chemistry relevant to air emissions predictions and aerosol formation, and by developing the knowledge base and computational tools to relate furnace model outputs to fouling and plugging of the convective sections of the boilers. The work done to date includes CFD model development and validation, acquisition of information on black liquor combustion fundamentals and development of improved burning models, char bed model development, and model application and simplification.

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...

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.

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

[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.

Pickering G.S. boiler repair: an example of planned maintenance

International Nuclear Information System (INIS)

Dalrymple, D.G.

1976-04-01

The first application of boiler repair tools and procedures is estimated to have yielded a four-fold return on the development investment. The need to develop such technology is a result of the environment in which boiler repairs must be made. As nuclear technology evolves and plants and components get bigger, equipment will increasingly have to be repaired in situ with minimum plant downtime and minimum exposure of repair personnel to radiation. This lecture traces development of the Pickering A boiler repair capability which is seen as an example of how utility and contractor should interact to anticipate and meet maintenance requirements. (author)

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...

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

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)

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.

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.

The orificing of once-through boilers for gas-cooled reactors

International Nuclear Information System (INIS)

Collier, J.G.; Whitmarsh-Everiss, M.J.

1986-01-01

The boilers at Hinkley Point B, Hunterston B (which are built to a common design) and Hartlepool and Heysham (which are identical to each other although different from Hinkley B/Hunterston B) are discussed. Heysham II and Torness have boilers developed from the Hinkley B/Hunterston B design. The boiler design is explained and the problems encountered are presented. The study presented in this address highlights the potential sensitivity of the performance of once-through boilers to the following factors - the uniformity of the gas inlet temperature profile, the choice of the operating point on the boiler characteristic (preferably this should be where the performance of the unit is not too sensitive to the primary side temperature and flow distribution); this can be achieved by greater levels of orificing reducing the steady state gains, and the various plant operating states which introduce asymmetries into the boundary conditions for the boiler. A number of computer codes have been used to model boiler performance. Using these, a new design was proposed for boiler feed regulating orifices and these revised orifices were installed during outages on the two Heysham reactors in 1985. (U.K.)

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...

Analysis on effects of energy efficiency regulations & standards for industrial boilers in China

Science.gov (United States)

Liu, Ren; Chen, Lili; Zhao, Yuejin; Liu, Meng

2017-11-01

The industrial boilers in China are featured by large quantity, wide distribution, high energy consumption and heavy environmental pollution, which are key problems faced by energy conservation and environmental protection in China. Meanwhile, industrial boilers are important equipment for national economy and people’s daily life, and energy conservation gets through all segments from type selection, purchase, installation and acceptance to fuel management, operation, maintenance and service. China began to implement such national mandatory standards and regulations for industrial boiler as GB24500-2009 The Minimum Allowable Values of Energy Efficiency and Energy Efficiency Grades of Industrial Boilers and TSG G002-2010 Supervision Regulation on Energy-Saving Technology for Boilers since 2009, which obviously promote the development of energy conservation of industrial boilers, but there are also some problems with the rapid development of technologies for energy conservation of industrial boilers. In this paper, the implementation of energy efficiency standards for industrial boilers in China and the significance are analyzed based on survey data, and some suggestions are proposed for the energy efficiency standards for industrial boilers. Support by Project 2015424050 of Special Fund for quality control Research in the Public Interest

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)

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

Increased combustion stability in modulating biomass boilers for district heating systems

Energy Technology Data Exchange (ETDEWEB)

Eriksson, Gunnar; Hermansson, Roger (eds.) [Lulea Univ. of Technology (Sweden)

2002-09-01

One of the problems in small district heating systems is the large load variation that must be handled by the system. If the boiler is designed to cover the needs during the coldest day in winter time in northern Europe it would have to run at loads as low as 10% of full load during summer time, when heat is needed only for tap water production. Load variations in small networks are quite fast and earlier investigations have shown that existing biomass boilers give rise to large amounts of harmful emissions at fast load variations and at low loads. The problem has been addressed in different ways: Three new boiler concepts have been realized and tested: A prototype of a 500 kW boiler with partitioned primary combustion chamber and supplied with a water heat store. A 10 kW bench scale combustor and a 500 kW prototype boiler based on pulsating combustion. Bench scale boilers to test the influence from applied sound on emissions and a 150 kW prototype boiler with a two-stage secondary vortex combustion chamber. Development of control and regulating equipment: Glow Guard, a control system using infra-red sensors to detect glowing char on the grate, has been constructed and tested. A fast prediction model that can be used in control systems has been developed. Simulation of the combustion process: Code to simulate pyrolysis/gasification of fuel on the grate has been developed. Combustion of the gas phase inside the combustion chamber has been simulated. The two models have been combined to describe the combustion process inside the primary chamber of a prototype boiler. A fast simulation code based on statistical methods that can predict the environmental performance of boilers has been developed. One of the boiler concepts matches the desired load span from 10 to 100% of full load with emissions far below the set limits for CO and THC and close to the set limits for NO{sub x}. The other boilers had a bit more narrow load range, one with very low emissions except for NO

FY 1999 Feasibility study on the environmentally-friendly coal utilization systems. Green Helmet Project (Circulating fluidized bed boiler Zaozhuang, Shangdong Province, China); 1999 nendo kankyo chowagata sekitan riyo system kanosei chosa jigyo seika hokokusho. Green helmet jigyo (junkan ryudosho boiler Chugoku Shangdong sho Zaozhuang)

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

The demonstration project is carried out in at Chaili coal mine in Shangdong Province, China for installation of and dissemination activities for circulating fluidized bed boilers to abate sulfur oxide emissions associated with utilization of coal, and the FY 1999 results are reported. The operating conditions were reviewed, and some recommendations were made for improving the operation procedures. Limestone was not used for desulfurization, and furnace temperature tended to increase due to increased size of the fluidizing particles. Therefore, it was recommended to use limestone at the design rate. The boiler was operated at a load exceeding the design level, and it was recommended to limit the load viewed from extending serviceability. The boiler start-up procedure was concretely proposed to use a mixed fuel of wood and coal instead of distillate oil, in order to reduce the start-up cost. The recommendations and design support activities for improving facilities included early stage repair of the damaged refractories. For build up of the ashes in the horizontal heat transfer section, the investigated design charts for improvement by installation of ash-discharging hopper were drawn and proposed. Maintenance-related information was given, including Chinese agencies for obtaining auxiliary facilities. (NEDO)

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.

Applications of electricity and corrosion. Precautions for use of metals and stainless and refractory alloys

International Nuclear Information System (INIS)

Gras, J.M.

1993-09-01

The development of applications of electricity poses highly diversified problems with materials where the resistance to corrosion prevails. Corrosion occurs under various conditions, which sometimes look harmless, and it covers diverse phenomenons linked to the nature of materials and to the physical and chemical context. However, in spite of the diversity of the processes used (electrical boilers, mechanical steam compression, heat pumps, Joule effect,) the knowledge required to approach the corrosion problems corresponds to a limited number of generic situations with regard not only to the phenomenons proper (general corrosion of copper, pitting and stress corrosion cracking of stainless steels, refractory alloys oxidation,) but also to chemical conditions which favour the corrosion (natural waters, acidic condensates, hot gases). This report is a short guide to anti-corrosion. With the aid of questions asked during the past few years, it aims to provide engineers in charge of the development of applications of electricity with a few recommendations upon the precautions for use of metallic materials. We analyze in turn the problems met with wet air and drying mists, chloride-containing neutral waters, alkaline waters and caustic media, acidic waters and concentrated acids, and, last, hot gases. We lay stress upon the behaviour of materials deemed to withstand corrosion under aqueous conditions (stainless steels and alloys, copper,titanium) and corrosion at high temperatures (refractory alloys). (author). 11 figs., 43 refs., 11 tabs

New configurations of a heat recovery absorption heat pump integrated with a natural gas boiler for boiler efficiency improvement

International Nuclear Information System (INIS)

Qu, Ming; Abdelaziz, Omar; Yin, Hongxi

2014-01-01

Highlights: • Thermal and heat transfer models of absorption heat pumps driven by exhaust gas, hot water, or natural gas. • Natural gas boiler combustion model. • Heat exchanger for condensing. • Experimental data of a hot water absorption heat pump. • Economic assessment of heat recovery absorption heat pump for improving natural gas boilers. - Abstract: Conventional natural gas-fired boilers exhaust flue gas direct to the atmosphere at 150–200 °C, which, at such temperatures, contains large amount of energy and results in relatively low thermal efficiency ranging from 70% to 80%. Although condensing boilers for recovering the heat in the flue gas have been developed over the past 40 years, their present market share is still less than 25%. The major reason for this relatively slow acceptance is the limited improvement in the thermal efficiency of condensing boilers. In the condensing boiler, the temperature of the hot water return at the range of 50–60 °C, which is used to cool the flue gas, is very close to the dew point of the water vapor in the flue gas. Therefore, the latent heat, the majority of the waste heat in the flue gas, which is contained in the water vapor, cannot be recovered. This paper presents a new approach to improve boiler thermal efficiency by integrating absorption heat pumps with natural gas boilers for waste heat recovery (HRAHP). Three configurations of HRAHPs are introduced and discussed. The three configurations are modeled in detail to illustrate the significant thermal efficiency improvement they attain. Further, for conceptual proof and validation, an existing hot water-driven absorption chiller is operated as a heat pump at operating conditions similar to one of the devised configurations. An overall system performance and economic analysis are provided for decision-making and as evidence of the potential benefits. These three configurations of HRAHP provide a pathway to achieving realistic high-efficiency natural

Status and Analysis on Effects of Energy Efficiency Standards for Industrial Boilers in China

Science.gov (United States)

Liu, Ren; Chen, Lili; Liu, Meng; Ding, Qing; Zhao, Yuejin

2017-11-01

Energy conservation and environmental protection is the basic policy of China, and is an important part of ecological civilization construction. The industrial boilers in China are featured by large quantity, wide distribution, high energy consumption and heavy environmental pollution, which are key problems faced by energy conservation and environmental protection in China. Meanwhile, industrial boilers are important equipment for national economy and people’s daily life, and energy conservation gets through all segments from type selection, purchase, installation and acceptance to fuel management, operation, maintenance and service. China began to implement such national mandatory standards and regulations for industrial boiler as GB24500-2009 The Minimum Allowable Values of Energy Efficiency and Energy Efficiency Grades of Industrial Boilers and TSG G002-2010 Supervision Regulation on Energy-Saving Technology for Boilers since 2009, which obviously promote the development of energy conservation of industrial boilers, but there are also some problems with the rapid development of technologies for energy conservation of industrial boilers. In this paper, the implementation of energy efficiency standards for industrial boilers in China and the significance are analyzed based on survey data, and some suggestions are proposed for the energy efficiency standards for industrial boilers.

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

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.)

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.

India's first 100,000 lbs/hr atmospheric bed boiler

International Nuclear Information System (INIS)

Mahajan, S.K.

1991-01-01

This paper covers the operating experience at the Petrochemical Complex of Hindustan Polymers, a Member Company of the UB Group, India, on the India's first 100,000 Lbs/hr atmospheric fluidized bed boiler supplied by Bharat Heavy Electricals Ltd., India. This atmospheric fluidized bed boiler is in operation for over 7 years with over 51,000 operating hours. The paper covers the details of onstream hours, actual thermal efficiency achieved, type of coal used and operational advantages of such boilers as per experience of Hindustan Polymers. Paper also highlights the maintenance and equipment problems as well as the developments which have taken place to overcome such problems. Details of experience in the operation of this boiler with baghouse system using abrasive and high ash coal are also covered

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.

Final stage of first supercritical 460MW{sub e} CFB boiler construction. First experience

Energy Technology Data Exchange (ETDEWEB)

Goral, Damian [Foster Wheeler Energia Polska (Poland); Ostrowski, Waldemar [PKE (Poland)

2009-07-01

Circulating fluidized bed (CFB) boiler technology has been growing in size and number over the past two decades and it has established its position as utility scale boiler technology. Plant sizes up to 300 MW{sub e} are in operation today and designs for larger boilers are being developed. The next natural step for CFB technology is to go for supercritical steam parameters and larger boiler sizes. A Polish utility company Poludniowy Koncern Energetyczny SA (PKE) placed an order to Foster Wheeler Energia Oy for a 460 MW{sub e} supercritical CFB boiler for their Lagisza power plant. Contract was signed at the end of year 2002 and the engineering work is now ongoing. This will be the first supercritical once-through CFB boiler in the world. A modern power plant is designed for high efficiency not only for economical reasons but also for enhanced environmental performance in terms of reduced emissions and quantity of ash generated due to lower fuel consumption. Cutting CO{sub 2} emissions is one of the main drivers. To achieve these goals, supercritical steam parameters have been applied. Now this technology is available also for CFB technology. This combines a high plant efficiency with the other well known benefits of CFB technology, such as: fuel flexibility, low emissions and high availability. The boiler design for 460 MW{sub e} Lagisza power plant utilizes low mass flux BENSON Vertical once-through technology developed and licensed by Siemens AG, Germany. CFB boiler with low and uniform furnace heat flux is extremely well suited for the Benson technology providing a stable operation of the boiler also during load changes and abnormal operation conditions. The paper describes the 460 MW{sub e} supercritical CFB boiler concept and presents the technical solutions of the boiler design with auxiliary equipment, as well as first experiences from boiler erection period and commissioning. In spite of achieving this remarkable milestone the development of the CFB

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...

Real-time monitoring energy efficiency and performance degradation of condensing boilers

International Nuclear Information System (INIS)

Baldi, Simone; Quang, Thuan Le; Holub, Ondrej; Endel, Petr

2017-01-01

Highlights: • Fully-fledged set of fault detection and diagnosis tools for condensing boilers. • Detection of boiler performance degradation in condensing and noncondensing mode. • Virtual sensing for estimation of water mass flow rate. • Optimal Kalman detection of actuator and sensor faults. • Structural properties for detection and isolation of faults. - Abstract: Condensing boilers achieve higher efficiency than traditional boilers by using waste heat in flue gases to preheat cold return water entering the boiler. Water vapor produced during combustion is condensed into liquid form, thus recovering its latent heat of vaporization, leading to around 10–12% increased efficiency. Many countries have encouraged the use of condensing boilers with financial incentives. It is thus important to develop software tools to assess the correct functioning of the boiler and eventually detect problems. Current monitoring tools are based on boiler static maps and on large sets of historical data, and are unable to assess timely loss of performance due to degradation of the efficiency curve or water leakages. This work develops a set of fault detection and diagnosis tools for dynamic energy efficiency monitoring and assessment in condensing boilers, i.e. performance degradation and faults can be detected using real-time measurements: this real-time feature is particularly relevant because of the limited amount of data that can be stored by state-of-the-art building energy management systems. The monitoring tools are organized as follows: a bimodal parameter estimator to detect deviations of the efficiency of the boiler from nominal values in both condensing and noncondensing mode; a virtual sensor for the estimation of the water mass flow rate; filters to detect actuator and sensor faults, possibly due to control and sensing problems. Most importantly, structural properties for detection and isolation of actuators and sensing faults are given: these properties are

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.

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)

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.)

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

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.)

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...

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

Methodology for the physical and chemical exergetic analysis of steam boilers

International Nuclear Information System (INIS)

Ohijeagbon, Idehai O.; Waheed, M. Adekojo; Jekayinfa, Simeon O.

2013-01-01

This paper presents a framework of thermodynamic, energy and exergy, analyses of industrial steam boilers. Mass, energy, and exergy analysis were used to develop a methodology for evaluating thermodynamic properties, energy and exergy input and output resources in industrial steam boilers. Determined methods make available an analytic procedure for the physical and chemical exergetic analysis of steam boilers for appropriate applications. The energy and exergy efficiencies obtained for the entire boiler was 69.56% and 38.57% at standard reference state temperature of 25 °C for an evaporation ratio of 12. Chemical exergy of the material streams was considered to offer a more comprehensive detail on energy and exergy resource allocation and losses of the processes in a steam boiler. - Highlights: ► We evaluated thermodynamic properties and performance variables associated with material streams. ► We analysed resources allocation, and magnitude of exergetic losses in steam boilers. ► Chemical exergy of material streams contributed to improved exergy values. ► High operational parameter will lead to higher boiler exergy. ► Exergy destroyed was higher in the combustion as against the heat exchanging unit

Development of diagnosis and repair system for steelmaking refractories; Seikoyo taikabutsu no shindan hoshu gijutsu no kakuritsu

Energy Technology Data Exchange (ETDEWEB)

Aso, S.; Harada, S.; Tsutsui, Y. [Nippon Steel Corp., Tokyo (Japan)

1996-06-01

The latest measurement equipment and repair method were introduced into the work area of all refractories in the process of torpedo cars, hot metal preliminary treatment, hot metal pans, secondary refining, and cast pans so as to improve the cost of the newest advanced steelmaking refractories. As a result, the refractory cost could be reduced by 10%. This paper introduces the improvement in RH refractories and refractories for hot metal preliminary treatment. As for basic items, in addition to the visual observation, the thickness of refractories was quantified using equipment (laser profile meter, thermotracer, and NS sensor) for the furnace stop in the minimum remaining length. An ITV was also installed in the facilities where the visual check is difficult to carry out. Repair is mainly done by spraying. A thermal spraying repair method with high durability was used for the repair. A method that relieves a thermal shock was used for preheating. Moreover, measures that make the temperature gradient in the thickness direction uniform by using newly developed microwave drying equipment were taken for drying of unburned refractories. 4 refs., 13 figs., 2 tabs.

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...

COAL-FIRED UTILITY BOILERS: SOLVING ASH DEPOSITION PROBLEMS; TOPICAL

International Nuclear Information System (INIS)

Christopher J. Zygarlicke; Donald P. McCollor; Steven A. Benson; Jay R. Gunderson

2001-01-01

The accumulation of slagging and fouling ash deposits in utility boilers has been a source of aggravation for coal-fired boiler operators for over a century. Many new developments in analytical, modeling, and combustion testing methods in the past 20 years have made it possible to identify root causes of ash deposition. A concise and comprehensive guidelines document has been assembled for solving ash deposition as related to coal-fired utility boilers. While this report accurately captures the current state of knowledge in ash deposition, note that substantial research and development is under way to more completely understand and mitigate slagging and fouling. Thus, while comprehensive, this document carries the title ''interim,'' with the idea that future work will provide additional insight. Primary target audiences include utility operators and engineers who face plant inefficiencies and significant operational and maintenance costs that are associated with ash deposition problems. Pulverized and cyclone-fired coal boilers are addressed specifically, although many of the diagnostics and solutions apply to other boiler types. Logic diagrams, ash deposit types, and boiler symptoms of ash deposition are used to aid the user in identifying an ash deposition problem, diagnosing and verifying root causes, determining remedial measures to alleviate or eliminate the problem, and then monitoring the situation to verify that the problem has been solved. In addition to a step-by-step method for identifying and remediating ash deposition problems, this guideline document (Appendix A) provides descriptions of analytical techniques for diagnostic testing and gives extensive fundamental and practical literature references and addresses of organizations that can provide help in alleviating ash deposition problems

Steam generation: fossil-fired systems: utility boilers; industrial boilers; boiler auxillaries; nuclear systems: boiling water; pressurized water; in-core fuel management; steam-cycle systems: condensate/feedwater; circulating water; water treatment

International Nuclear Information System (INIS)

Anon.

1982-01-01

A survey of development in steam generation is presented. First, fossil-fired systems are described. Progress in the design of utility and industrial boilers as well as in boiler auxiliaries is traced. Improvements in coal pulverizers, burners that cut pollution and improve efficiency, fans, air heaters and economisers are noted. Nuclear systems are then described, including the BWR and PWR reactors, in-core fuel management techniques are described. Finally, steam-cycle systems for fossil-fired and nuclear power plants are reviewed. Condensate/feedwater systems, circulating water systems, cooling towers, and water treatment systems are discussed

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

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.

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.

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...

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.

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.

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...

Developing the Pediatric Refractory Epilepsy Questionnaire: a pilot study.

Science.gov (United States)

Purusothaman, Vaishnavi; Ryther, Robin C C; Bertrand, Mary; Harker, Lisa A; Jeffe, Donna B; Wallendorf, Michael; Smyth, Matthew D; Limbrick, David D

2014-08-01

Up to 14% of children with epilepsy continue to experience seizures despite having appropriate medical therapy and develop medically refractory epilepsy (MRE). Assessing clinical outcomes and therapeutic efficacy in children with MRE undergoing palliative epilepsy surgery has been challenging because of the lack of a quantitative instrument capable of estimating the clinical status of these patients. The ideal instrument would at once consider seizure control, neurodevelopment, caregiver burden, and quality of life. The purpose of this study was to develop and pilot the Pediatric Refractory Epilepsy Questionnaire (PREQ), a quantitative instrument to assess the severity and individual burden of epilepsy in children with MRE undergoing palliative epilepsy treatments. The caregivers of 25 patients with MRE completed the PREQ and the Quality of Life in Childhood Epilepsy (QOLCE) measure and participated in a semistructured interview. Medical records of the patients were reviewed, an Early Childhood Epilepsy Severity Scale (E-CHESS) score was calculated, and a Global Assessment of Severity of Epilepsy (GASE) score was obtained for each patient. The initial PREQ was modified based on the analysis of responses, association with previously validated scales, comments from caregivers, and expertise of the PREQ panelists. Pediatric Refractory Epilepsy Questionnaire subscale scores were calculated based on clinical paradigm and compared with independent measures of seizure severity and quality of life. Significant correlations were observed between the seizure severity subscale and the GASE score (r=0.55) and between the mood subscale and the well-being score (r=0.61) on the QOLCE. Significant correlations were also observed between the caregiver rating of seizure severity and the GASE score (r=0.53), the social activity score (r=0.57), and the behavior score (r=0.43) on the QOLCE. Correlations between the caregiver rating of quality of life and the quality of life score (r=0

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

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...

Atmospheric emission of nitrogen oxide from kraft recovery boilers in Sweden

International Nuclear Information System (INIS)

Kjoerk, Anders; Herstad Swaerd, Solvie

2000-05-01

Recovery boiler NO x emissions are low compared with those from power boilers. However tighter environmental requirements to decrease the acidic emissions implies that all sources have to be addressed. There are an ongoing evaluation and development of NO x control technologies in the pulp industry. Basically air staging, selective catalytic reduction, SCR, and selective noncatalytic reduction, SNCR, have been discussed. Other NO x control options may be available as a result of ongoing research and development. As a background in the work to reduce the acid rain it has been considered necessary to have a good picture of the NO x emission from recovery boilers, and the Thermal Engineering Research Institute in Sweden have therefore sponsored this study. The intention is to give a good general view and try to explain the reasons for the large differences between boilers. Data from the 30 kraft recovery boilers which were in operation in Sweden during 1999 have been collected. Both NO x levels and specific conditions which could have an influence on the level have been included. The evaluation show a clear correlation between the nitrogen content in the liquor and the NO x level. It seams also that a long retention time in the furnace give an opportunity to reduce the amount of nitrogen oxide. For most boilers in Sweden the NO x levels are reported in mg/MJ and comparison could be done between different types of boilers. However for recovery boilers there could be a large uncertainty in the calculation which gives the amount (mg) of NO x , the definition of the heat input to be used (MJ) is either not clear. As a base for the study the measured concentration in ppm is used instead. The reported values are in the range of 30 - 100 ppm, however the majority of the boilers operate in a more narrow range 60-80 ppm. Air staging and other combustion methods could not reasonably reduce the NO x emission with more than 20% in the next decade. If the goal is higher other

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.

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 ...

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

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.

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

Fuel quality and its effect on the design of power boilers in the USA

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.

1984-05-01

Statistical data, taken from Power, Proceedings of the American Power Conference and others, on developments since the 1950s in boiler design caused by the increasing use of lower quality fuel (subbituminous and lignite coals) are presented. The effect of pollution regulations in the USA on boiler design is discussed. The results of a 16 year study by the TVA on the decrease in coal quality fired in its boilers and its effect on boiler efficiency are presented. Methods of transport are surveyed. Descriptions and characteristics of several modern boilers designed by Babcock and Wilcox, Combustion Engineering, Foster-Wheeler and Riley Stoker are given. 13 references.

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...

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)

Development of various welding techniques for refractory and reactive metals and alloys

International Nuclear Information System (INIS)

Tonpe, Sunil; Saibaba, N.

2016-01-01

Nuclear Fuel Complex (NFC), Hyderabad, India with its excellent manufacturing facilities, produces nuclear fuel and structural components for nuclear reactors. NFC has taken up the challenging job of production of various critical components made out of refractory and reactive metals and alloys for nuclear and aerospace applications as an indigenization import substitute program. Refractory metals are prime candidates for many high temperature aerospace components because of refractory metal's high melting points and inherent creep resistance. The use of refractory metals is often limited because of their poor room temperature properties, inadequate oxidation resistance at elevated temperatures, difficulties associated with joining or welding etc. These advanced materials demand stringent requirement with respect to chemistry, dimensional tolerances, mechanical and metallurgical properties. This paper discusses in detail various welding techniques adopted in NFC for refractory and reactive metals and alloys such as Nb, Zr, Ti, Ta, Zircaloy, Titanium-half alloy etc. to manufacture various components and assemblies required for nuclear and aerospace applications

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...

CONVERSION OF BOILER-HOUSES IN MINI-THERMAL POWER STATIONS

Directory of Open Access Journals (Sweden)

V. A. Sednin

2005-01-01

Full Text Available One of the methods that makes it possible to increase operational efficiency of heat supply  systems is development of power-and-heat generation on the basis of boiler houses of small and average power. The paper gives main prerequisites for selection of variants and power of power-and-heat generation (cogeneration installations on the basis of gas-piston engines which are to be used at heating boiler houses.

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.

Modelling of limestone injection for SO2 capture in a coal fired utility boiler

International Nuclear Information System (INIS)

Kovacik, G.J.; Reid, K.; McDonald, M.M.; Knill, K.

1997-01-01

A computer model was developed for simulating furnace sorbent injection for SO 2 capture in a full scale utility boiler using TASCFlow TM computational fluid dynamics (CFD) software. The model makes use of a computational grid of the superheater section of a tangentially fired utility boiler. The computer simulations are three dimensional so that the temperature and residence time distribution in the boiler could be realistically represented. Results of calculations of simulated sulphur capture performance of limestone injection in a typical utility boiler operation were presented

CFD Modelling of Biomass Combustion in Small-Scale Boilers. Final Report

Energy Technology Data Exchange (ETDEWEB)

Xue-Song Bai; Griselin, Niklas; Klason, Torbern; Nilsson, Johan [Lund Inst. of Tech. (Sweden). Dept. of Heat and Power Engineering

2002-10-01

This project deals with CFD modeling of combustion of wood in fixed bed boilers. A flamelet model for the interaction between turbulence and chemical reactions is developed and applied to study small-scale boiler. The flamelet chemistry employs 43 reactive species and 174 elementary reactions. It gives detailed distributions of important species such as CO and NO{sub x} in the flow field and flue gas. Simulation of a small-scale wood fired boiler measured at SP Boraas (50 KW) shows that the current flamelet model yields results agreeable to the available experimental data. A detailed chemical kinetic model is developed to study the bed combustion process. This model gives boundary conditions for the CFD analysis of gas phase volatile oxidation in the combustion chambers. The model combines a Functional Group submodel with a Depolymerisation, Vaporisation and Crosslinking submodel. The FG submodel simulates how functional groups decompose and form light gas species. The DVC submodell predicts depolymerisation and vaporisation of the macromolecular network and this includes bridge breaking and crosslinking processes, where the wood structure breaks down to fragments. The light fragments form tar and the heavy ones form metaplast. Two boilers firing wood log/chips are studied using the FG-DVC model, one is the SP Boraas small-scale boiler (50 KW) and the other is the Sydkraft Malmoe Vaerme AB's Flintraennan large-scale boiler (55 MW). The fix bed is assumed to be two zones, a partial equilibrium drying/devolatilisation zone and an equilibrium zone. Three typical biomass conversion modes are simulated, a lean fuel combustion mode, a near-stoichiometric combustion and a fuel rich gasification mode. Detailed chemical species and temperatures at different modes are obtained. Physical interpretation is provided. Comparison of the computational results with experimental data shows that the model can reasonably simulate the fixed bed biomass conversion process. CFD

DEVELOPMENT OF THE BOILER FOR COMBUSTION OF AGRICULTURAL BIOMASS BY PRODUCTS

Directory of Open Access Journals (Sweden)

Valentina Turanjanin

2010-01-01

Full Text Available Republic of Serbia consumes about 15 million tons of equivalent oil per year (Mtoe. At the same time potential of the renewable energy sources is about 3,5 Mtoe/year. Main renewable source is biomass, with its potential of about 2,6 Mtoe/year, and 60% of the total biomass source is of agricultural origin. Mainly, that type of biomass is collected, transported and stored in form of bales. At the same time in one of the largest agricultural companies in Serbia (PKB there are over 2000 ha of soya plantations, and also 4000 t/year of baled soya straw available, none of which being used for energy purposes. Therefore, efforts have been made in the Laboratory for Thermal Engineering and Energy of the "Vinča" Institute to develop a technology for utilizing bales of various sizes and shapes for energy production. Satisfactory test results of the 1 MW experimental facility - low CO levels and stable thermal output - led to the building-up of a 1.5 MW soya straw bales-fired hot water boiler, with cigarette type of combustion, for the purposes of greenhouse and office heating in the PKB. Further more, achieving good results in exploitation of that hot water boiler, the next step is building up the first combined heat and power (electricity production facility (CHP, which will use agricultural biomass as a fuel, in Serbia.

Slagging gasifier refractories. A new pathway to longer refractory life

Energy Technology Data Exchange (ETDEWEB)

Schnake, Mark [Harbinson-Walker Refractories Company, Mexico, MO (United States)

2013-07-01

Solid fuel slagging gasification to convert coal or petroleum coke feedstocks into syngas has rapidly evolved over the last 25 years. The gasifier is a high temperature, high pressure reaction chamber. Operating temperatures are between 1250 and 1575 C. Pressures will be between 20.4 and 68 atm. Syngas has been typically used for chemical feedstocks, fuel for power plants, or for steam and hydrogen generation in other industrial applications. Ash which comes from the solid fuel during gasification has many impurities. It melts during the gasifier reactor operation forming a liquid that penetrates the refractory lining. Given time, the refractory will wear away from thermal spalling, structural spalling, or overheating of the refractory. In some cases, all three wear mechanisms are seen in the same gasifier lining. Industry users have identified refractory life as one major limiting factor in worldwide use of this technology. Users have stated if the refractory liner can increase on-line availability of the gasifier operation, more industry acceptance of this technology is possible. Harbison-Walker Refractories Company will review destructive factors affecting lining life and discuss new refractory materials that have dramatically increased gasifier lining life and reliability. New refractory materials will be presented and supported by field trial results and post mortem analysis.

A bottom-up method to develop pollution abatement cost curves for coal-fired utility boilers

International Nuclear Information System (INIS)

Vijay, Samudra; DeCarolis, Joseph F.; Srivastava, Ravi K.

2010-01-01

This paper illustrates a new method to create supply curves for pollution abatement using boiler-level data that explicitly accounts for technology cost and performance. The Coal Utility Environmental Cost (CUECost) model is used to estimate retrofit costs for five different NO x control configurations on a large subset of the existing coal-fired, utility-owned boilers in the US. The resultant data are used to create technology-specific marginal abatement cost curves (MACCs) and also serve as input to an integer linear program, which minimizes system-wide control costs by finding the optimal distribution of NO x controls across the modeled boilers under an emission constraint. The result is a single optimized MACC that accounts for detailed, boiler-specific information related to NO x retrofits. Because the resultant MACCs do not take into account regional differences in air-quality standards or pre-existing NO x controls, the results should not be interpreted as a policy prescription. The general method as well as NO x -specific results presented here should be of significant value to modelers and policy analysts who must estimate the costs of pollution reduction.

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.

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.

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)

Improving boiler unit performance using an optimum robust minimum-order observer

International Nuclear Information System (INIS)

Moradi, Hamed; Bakhtiari-Nejad, Firooz

2011-01-01

Research highlights: → Multivariable model of a boiler unit with uncertainty. → Design of a robust minimum-order observer. → Developing an optimal functional code in MATLAB environment. → Finding optimum region of observer-based controller poles. → Guarantee of robust performance in the presence of parametric uncertainties. - Abstract: To achieve a good performance of the utility boiler, dynamic variables such as drum pressure, steam temperature and water level of drum must be controlled. In this paper, a linear time invariant (LTI) model of a boiler system is considered in which the input variables are feed-water and fuel mass rates. Due to the inaccessibility of some state variables of boiler system, a minimum-order observer is designed based on Luenberger's model to gain an estimate state x-tilde of the true state x. Low cost of design and high accuracy of states estimation are the main advantages of the minimum-order observer; in comparison with previous designed full-order observers. By applying the observer on the closed-loop system, a regulator system is designed. Using an optimal functional code developed in MATLAB environment, desired observer poles are found such that suitable time response specifications of the boiler system are achieved and the gain and phase margin values are adjusted in an acceptable range. However, the real dynamic model may associate with parametric uncertainties. In that case, optimum region of poles of observer-based controller are found such that the robust performance of the boiler system against model uncertainties is guaranteed.

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

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.

High alumina refractories

International Nuclear Information System (INIS)

Simao, L.C.; Lopes, A.B.; Galvao Filho, N.B.; Souza, R.B. de

1989-01-01

High alumina refractories with 92 to 96.5% Al 2 O 3 were produced using brown and white fused as aggregate. Those refractories present only alumina-α and mullite as crystalline mineralogical phase. Other physical and chemical characteristics are similar to the ones found in refractories produced in Brazil, Japan and U.S.A. The most important physical and chemical tests used for the characterization of the raw materials and refractories, complemented by those realized at high temperatures, plus X-ray Difractometry and optical microscopy are presented, besides the refractory formulation and main parameters of production [pt

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)

Development of a test set for adjustment of residential furnaces and boilers. Final report

Energy Technology Data Exchange (ETDEWEB)

1980-01-01

A program was undertaken to design and develop a portable test set for simplified field adjustment of residential furnaces and boilers to achieve peak operating efficiency. Advanced technology was applied to provide continuous analysis of flue gases and the display of temperature, oxygen concentrations, smoke value and furnace efficiency. Prototype models were constructed and delivered to Brookhaven National Laboratory for further testing. A survey of furnace dealers was conducted, and a commercialization plan was developed based on survey responses and the status of the equipment developed under the program. Goals for a marketable test set and development steps to achieve a projected energy savings were determined and recommended. Recommendations for specific areas of further development are included.

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.

Basics about online boiler cleaning according to the Schwandorf principle; Grundlagen zur Online-Kesselreinigung nach dem Schwandorfer Prinzip

Energy Technology Data Exchange (ETDEWEB)

Krueger, Joerg [VWT Ing.-Buero, Schwandorf (Germany); Krueger, Sascha [IBK-Verfahrenstechnik, Bad Berka (Germany)

2013-10-01

In the Schwandorf waste-to-energy (WtE) plant more than ten years ago a wet online boiler cleaning system was developed which has the capability to clean the radiation passes of (WtE-, biomass- and refuse derived fuel (RDF)) boilers without damaging the boiler. During the development it was recognised that the method of atomising the washing agent (water) is highly influencing the effectiveness of cleaning by securing parts of the boiler (membrane walls). (orig.)

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.

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

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.

The design development and commissioning of two distributed computer based boiler control systems

International Nuclear Information System (INIS)

Collier, D.; Johnstone, L.R.; Pringle, S.T.; Walker, R.W.

1980-01-01

The CEBG N.E. Region has recently commissioned two major boiler control schemes using distributed computer control system. Both systems have considerable development potential to allow modifications to meet changing operational requirements. The distributed approach to control was chosen in both instances so as to achieve high control system availability and as a method of easing the commissioning programs. The experience gained with these two projects has reinforced the view that distributed computer systems show advantages over centralised single computers especially if software is designed for the distributed system. (auth)

Computer control for the Tampella double-grate boiler. Tampella-kaksoisarinan toiminnan ja arinapolton ohjaustutkimus

Energy Technology Data Exchange (ETDEWEB)

Imelaeinen, K; Petaenen, P; Koskela, O; Sutinen, R

1986-01-01

Most of the new boilers recently installed in Finland are multifuel boilers using woodwastes and peat as the main fuel. Although burning of woodwastes and peat is economically most attractive, noticeable difficulties are encountered in the combustion control due to such fuel characteristics as varying physical properties, moisture value etc. In this project a control strategy was developed for the Tampella double-grate boiler. Special attention was paid to the grate burning properties and the function of the mechanical grate. The control system consists of the optimization of the Tampella multifuel boiler (K10) and the steam levelling control system of the power plant. Because of the rapid load fluctuations caused by boarding machine web breaks or fluctuations in digester house steam demand, a steam network levelling system was installed in the power plant. The main object of the project was to minimize oil burning in the K10-boiler and the whole power plant and the optimization of grate burning. The practical results of the mechanical grate function control and air distribution optimization are very encouraging. During normal operation boiler pressure and excess oxygen are very stable compared with other grate boilers. The response time of boiler load changes is also very fast compared to other boilers of this type. The main object of the whole boiler installation project was to decrease oil consumption by effective burning of domestic fuels. This object was attained better than was predicted.

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

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...

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

Merits of using andalusite-based refractories compared to bauxite-based refractories

OpenAIRE

Nyoka, M.; Brazier, D.; Courtney, T.; Parry, R.A.

2013-01-01

Historically bauxite-based refractories have been used in applications where andalusite-based refractories could work. Bauxite-based refractories were chosen over andalusite-based refractories mainly because of the availability of low-cost Chinese bauxite and also because many furnaces were designed by international companies that cannot easily access high-quality products. Currently, the availability of low-cost bauxite is under threat as a result of high export duties and tariffs as well as...

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.

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.

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.

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.)

Enviro-exergy sustainability analysis of boiler evolution in district energy system

International Nuclear Information System (INIS)

Compton, M.; Rezaie, B.

2017-01-01

Investigations into energy resources are important from the point of energy sustainability. The principal objective of this study is to investigate the evolution of the operating boilers at the University of Idaho (UI) district energy plant through an exergy analysis. The biomass boiler uses western red cedar chips from nearby lumber mills and provides 95% of the steam requirements of the main campus of UI in Moscow, ID, USA. Thermodynamic analysis reveals a thermal efficiency of 76% and an exergy efficiency of 24% for the biomass boiler. A combustion model is developed to determine the primary emissions products of both the bone dry wood chips and natural gas fuels. CO 2 comprises 26% of the bone dry biomass emissions and 8% of the natural gas emissions products. Testing results of the biomass boiler exhaust stack show CO 2 emissions of 14% when an average moisture content of 33% is accounted for. An overview of the evolution of the energy plant is discussed, showing the generational differences in each boiler. By using a biomass fuel source, the cost per 1000 kg of steam produced is on average 63% lower than using natural gas, resulting in savings of over $1 million annually. - Highlights: • Exergy efficiency comparison of biomass and natural gas boilers. • Moisture content in biomass reduces average heating value and exergy efficiency. • Local sustainable energy sources can result in economic savings over fossil fuels. • Older boilers can have comparable efficiencies with newer ones after improvements.

METHANE de-NOX FOR UTILITY PC BOILERS

Energy Technology Data Exchange (ETDEWEB)

Joseph Rabovitser

2000-07-05

The overall project objective is the development and validation of an innovative combustion system, based on a novel coal preheating concept prior to combustion, that can reduce NO{sub x} emissions to 0.15 lb/million Btu or less on utility pulverized coal (PC) boilers. This NO{sub x} reduction should be achieved without loss of boiler efficiency or operating stability, and at more than 25% lower levelized cost than state-of-the-art SCR technology. A further objective is to make this technology ready for full-scale commercial deployment by 2002-2003 in order to meet an anticipated market demand for NO{sub x} reduction technologies resulting from the EPA's NO{sub x} SIP call.

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.

Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers

Energy Technology Data Exchange (ETDEWEB)

Adams, Bradley [Univ. of Utah, Salt Lake City, UT (United States); Davis, Kevin [Univ. of Utah, Salt Lake City, UT (United States); Senior, Constance [Univ. of Utah, Salt Lake City, UT (United States); Shim, Hong Shim [Univ. of Utah, Salt Lake City, UT (United States); Otten, Brydger Van [Univ. of Utah, Salt Lake City, UT (United States); Fry, Andrew [Univ. of Utah, Salt Lake City, UT (United States); Wendt, Jost [Univ. of Utah, Salt Lake City, UT (United States); Eddings, Eric [Univ. of Utah, Salt Lake City, UT (United States); Paschedag, Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Shaddix, Christopher [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cox, William [Brigham Young Univ., Provo, UT (United States); Tree, Dale [Brigham Young Univ., Provo, UT (United States)

2013-09-30

Reaction Engineering International (REI) managed a team of experts from University of Utah, Siemens Energy, Praxair, Vattenfall AB, Sandia National Laboratories, Brigham Young University (BYU) and Corrosion Management Ltd. to perform multi-scale experiments, coupled with mechanism development, process modeling and CFD modeling, for both applied and fundamental investigations. The primary objective of this program was to acquire data and develop tools to characterize and predict impacts of CO{sub 2} flue gas recycle and burner feed design on flame characteristics (burnout, NO{sub x}, SO{sub x}, mercury and fine particle emissions, heat transfer) and operational concerns (fouling, slagging and corrosion) inherent in the retrofit of existing coal-fired boilers for oxy-coal combustion. Experimental work was conducted at Sandia National Laboratories’ Entrained Flow Reactor, the University of Utah Industrial Combustion Research Facility, and Brigham Young University. Process modeling and computational fluid dynamics (CFD) modeling was performed at REI. Successful completion of the project objectives resulted in the following key deliverables: 1) Multi-scale test data from 0.1 kW bench-scale, 100 kW and 200 kW laboratory-scale, and 1 MW semi-industrial scale combustors that describe differences in flame characteristics, fouling, slagging and corrosion for coal combustion under air-firing and oxygen-firing conditions, including sensitivity to oxy-burner design and flue gas recycle composition. 2) Validated mechanisms developed from test data that describe fouling, slagging, waterwall corrosion, heat transfer, char burnout and sooting under coal oxy-combustion conditions. The mechanisms were presented in a form suitable for inclusion in CFD models or process models. 3) Principles to guide design of pilot-scale and full-scale coal oxy-firing systems and flue gas recycle configurations, such that boiler operational impacts from oxy-combustion retrofits are minimized. 4

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...

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...

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

Advanced, Low/Zero Emission Boiler Design and Operation

Energy Technology Data Exchange (ETDEWEB)

Babcock/Wilcox; Illinois State Geological; Worley Parsons; Parsons Infrastructure/Technology Group

2007-06-30

In partnership with the U.S. Department of Energy's National Energy Technology Laboratory, B&W and Air Liquide are developing and optimizing the oxy-combustion process for retrofitting existing boilers as well as new plants. The main objectives of the project is to: (1) demonstrate the feasibility of the oxy-combustion technology with flue gas recycle in a 5-million Btu/hr coal-fired pilot boiler, (2) measure its performances in terms of emissions and boiler efficiency while selecting the right oxygen injection and flue gas recycle strategies, and (3) perform technical and economic feasibility studies for application of the technology in demonstration and commercial scale boilers. This document summarizes the work performed during the period of performance of the project (Oct 2002 to June 2007). Detailed technical results are reported in corresponding topical reports that are attached as an appendix to this report. Task 1 (Site Preparation) has been completed in 2003. The experimental pilot-scale O{sub 2}/CO{sub 2} combustion tests of Task 2 (experimental test performance) has been completed in Q2 2004. Process simulation and cost assessment of Task 3 (Techno-Economic Study) has been completed in Q1 2005. The topical report on Task 3 has been finalized and submitted to DOE in Q3 2005. The calculations of Task 4 (Retrofit Recommendation and Preliminary Design of a New Generation Boiler) has been completed in 2004. In Task 6 (engineering study on retrofit applications), the engineering study on 25MW{sub e} unit has been completed in Q2, 2008 along with the corresponding cost assessment. In Task 7 (evaluation of new oxy-fuel power plants concepts), based on the design basis document prepared in 2005, the design and cost estimate of the Air Separation Units, the boiler islands and the CO{sub 2} compression and trains have been completed, for both super and ultra-supercritical case study. Final report of Task-7 is published by DOE in Oct 2007.

Boiler materials for ultra supercritical coal power plants

Energy Technology Data Exchange (ETDEWEB)

Purgert, Robert [Energy Industries of Ohio, Independence, OH (United States); Shingledecker, John [Electric Power Research Inst., Palo Alto, CA (United States); Pschirer, James [Alstom Power Inc., Windsor, CT (Untied States); Ganta, Reddy [Alstom Power Inc., Windsor, CT (Untied States); Weitzel, Paul [The Babcock & Wilcox Company, Baberton, OH (United States); Sarver, Jeff [The Babcock & Wilcox Company, Baberton, OH (United States); Vitalis, Brian [Riley Power Inc., Worchester, WA (United States); Gagliano, Michael [Foster Wheeler North America Corp., Hampton, NJ (United States); Stanko, Greg [Foster Wheeler North America Corp., Hampton, NJ (United States); Tortorelli, Peter [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2015-12-29

The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have undertaken a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of advanced ultrasupercritical (A-USC) steam conditions up to 760°C (1400°F) and 35 MPa (5000 psi). A limiting factor to achieving these higher temperatures and pressures for future A-USC plants are the materials of construction. The goal of this project is to assess/develop materials technology to build and operate an A-USC boiler capable of delivering steam with conditions up to 760°C (1400°F)/35 MPa (5000 psi). The project has successfully met this goal through a focused long-term public-private consortium partnership. The project was based on an R&D plan developed by the Electric Power Research Institute (EPRI) and an industry consortium that supplemented the recommendations of several DOE workshops on the subject of advanced materials. In view of the variety of skills and expertise required for the successful completion of the proposed work, a consortium led by the Energy Industries of Ohio (EIO) with cost-sharing participation of all the major domestic boiler manufacturers, ALSTOM Power (Alstom), Babcock and Wilcox Power Generation Group, Inc. (B&W), Foster Wheeler (FW), and Riley Power, Inc. (Riley), technical management by EPRI and research conducted by Oak Ridge National Laboratory (ORNL) has been developed. The project has clearly identified and tested materials that can withstand 760°C (1400°F) steam conditions and can also make a 700°C (1300°F) plant more economically attractive. In this project, the maximum temperature capabilities of these and other available high-temperature alloys have been assessed to provide a basis for

Modeling and optimization of processes for clean and efficient pulverized coal combustion in utility boilers

Directory of Open Access Journals (Sweden)

Belošević Srđan V.

2016-01-01

Full Text Available Pulverized coal-fired power plants should provide higher efficiency of energy conversion, flexibility in terms of boiler loads and fuel characteristics and emission reduction of pollutants like nitrogen oxides. Modification of combustion process is a cost-effective technology for NOx control. For optimization of complex processes, such as turbulent reactive flow in coal-fired furnaces, mathematical modeling is regularly used. The NOx emission reduction by combustion modifications in the 350 MWe Kostolac B boiler furnace, tangentially fired by pulverized Serbian lignite, is investigated in the paper. Numerical experiments were done by an in-house developed three-dimensional differential comprehensive combustion code, with fuel- and thermal-NO formation/destruction reactions model. The code was developed to be easily used by engineering staff for process analysis in boiler units. A broad range of operating conditions was examined, such as fuel and preheated air distribution over the burners and tiers, operation mode of the burners, grinding fineness and quality of coal, boiler loads, cold air ingress, recirculation of flue gases, water-walls ash deposition and combined effect of different parameters. The predictions show that the NOx emission reduction of up to 30% can be achieved by a proper combustion organization in the case-study furnace, with the flame position control. Impact of combustion modifications on the boiler operation was evaluated by the boiler thermal calculations suggesting that the facility was to be controlled within narrow limits of operation parameters. Such a complex approach to pollutants control enables evaluating alternative solutions to achieve efficient and low emission operation of utility boiler units. [Projekat Ministarstva nauke Republike Srbije, br. TR-33018: Increase in energy and ecology efficiency of processes in pulverized coal-fired furnace and optimization of utility steam boiler air preheater by using in

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

Development of realtime monitoring technology for laser photoreaction product - Development of glow discharge-mass spectrometry (GD-MS) hybrid techniques for trace analysis of refractory elements

Energy Technology Data Exchange (ETDEWEB)

Lee, Sang Chun [Kyungnam University, Masan (Korea); Kim, Ha Suck [Seoul National University, Seoul (Korea); Kim, Hyo Jin [Dongduk Women' s University, Seoul (Korea)

2000-04-01

This research is focusing on development of hybrid techniques of glow discharge-mass spectrometry for the trace analysis of refractory elements. At first, we developed a glow discharge(GD) ionization cell and its characteristics was investigated. The new GD cell was designed based on direct current hollow cathode glow discharge and it is used for quadrupole mass analyzer and time-of-flight mass analyzer. Currently, GD-quadrupole mass spectrometry is working for the analysis of refractory elements. The experimental results show relatively good for trace analysis. In addition, ion mobile spectrometry using plasma and liquid discharge technique were investigated for the analysis of refractory elements and both techniques need more investigation to deduce the their usefulness. 30 refs., 67 figs., 4 tabs. (Author)

Curbing Air Pollution and Greenhouse Gas Emissions from Industrial Boilers in China

Energy Technology Data Exchange (ETDEWEB)

Shen, Bo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Lynn K [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Hongyou [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Liu, Xu [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Tsen, Katherine [Univ. of California, Berkeley, CA (United States); Xiangyang, Wei [National Energy Conservation Center (China); Yunpeng, Zhang [National Energy Conservation Center (China); Jian, Guan [China Special Equipment Inspection & Test Inst. (China); Rui, Hou [China Machinery Industry Conservation & Resource Utilization Center (China); Junfeng, Zhang [China National Offshore Oil Corp. (China); Yuqun, Zhuo [Tsinghua Univ., Beijing (China); Shumao, Xia [China Energy Conservation & Environmental Protection Group (China); Yafeng, Han [Xi' an Jiatong Univ. (China); Manzhi, Liu [China Univ. of Mining and Technology (China)

2015-10-28

China’s industrial boiler systems consume 700 million tons of coal annually, accounting for 18% of the nation’s total coal consumption. Together these boiler systems are one of the major sources of China’s greenhouse gas (GHG) emissions, producing approximately 1.3 gigatons (Gt) of carbon dioxide (CO₂) annually. These boiler systems are also responsible for 33% and 27% of total soot and sulfur dioxide (SO2) emissions in China, respectively, making a substantial contribution to China’s local environmental degradation. The Chinese government - at both the national and local level - is taking actions to mitigate the significant greenhouse gas (GHG) emissions and air pollution related to the country’s extensive use of coal-fired industrial boilers. The United States and China are pursuing a collaborative effort under the U.S.-China Climate Change Working Group to conduct a comprehensive assessment of China’s coal-fired industrial boilers and to develop an implementation roadmap that will improve industrial boiler efficiency and maximize fuel-switching opportunities. Two Chinese cities – Ningbo and Xi’an – have been selected for the assessment. These cities represent coastal areas with access to liquefied natural gas (LNG) imports and inland regions with access to interprovincial natural gas pipelines, respectively.

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.

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...

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...

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,…

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.

Potential refractory alloy requirements for space nuclear power applications

International Nuclear Information System (INIS)

Cooper, R.H. Jr.

1984-01-01

In reviewing design requirements for refractory alloys for space nuclear applications, several key points are identified. First, the successful utilization of refractory alloys is considered an enabling requirement for the successful deployment of high efficiency, lightweight, and small space nuclear systems. Second, the recapture of refractory alloy nuclear technology developed in the 1960s and early 1970s appears to be a pacing activity in the successful utilization of refractory alloys. Third, the successful application of refractory alloys for space nuclear applications will present a significant challenge to both the materials and the systems design communities

Material development for waste to energy plants. Overlay welding and refractory linings. Final report

Energy Technology Data Exchange (ETDEWEB)

Noergaard Hansson, A.

2011-02-15

Waste is an extremely corrosive fuel. In order to recover a higher percentage of the energy in waste, waste incineration plants have developed from purely heat producing units to heat and power producing units. The change in concept results in higher material temperatures and thereby faster material degradation. As a result material failures have been observed in many waste incineration plants. The purpose of this project was to develop materials with higher resistance to the corrosive elements, in order to reduce the cost of maintenance, increase the availability, and increase the efficiency. The focus is on overlay welding and refractory linings. Inconel 625, alloy 50, alloy 686, and Super 625 offer equivalent corrosion protection at panel walls. 100% overlay performs better than 50% overlay. The corrosion morphology changes with increasing temperature from pitting and general corrosion to pitting and selective corrosion (dendritic core or grain boundaries). The previously observed detrimental effect of Fe on the corrosion resistance was not confirmed. It probably depends on factors such as microstructure of the alloy and local metal temperature. Ni-overlay also reduces the corrosion rates on superheater tubes. However, the superheater environment is less aggressive than the water wall environment. Failure of refractory linings is linked to excess porosity, detrimental reactions between raw materials and other mix constituents, volume growth reactions between base material and salt depositions, and thermal stress induced crack formation. Free water and not decomposition of hydrates causes spalling and cracking during the initial heating of refractory linings. Finite Element analysis confirms the stress levels between steel and refractory with the higher stress level at the top of the panel wall tube. A number of LCC mixes were formulated, adjusted and tested. Mixes with low open porosities ({approx} 10%) and state of the art resistance to KCl were achieved. (LN)

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.

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.

Final stage of first super-critical 460 MW CFB boiler construction. First experience

Energy Technology Data Exchange (ETDEWEB)

Ostrowski, Waldemar [PKE, Lagisza Power Plant (Poland); Goral, Damian [Foster Wheeler Energia Polska, Sosnowiec (Poland)

2010-07-01

Steam boilers with circulating fluidised bed combustion have been advanced in the past years and proved well as large-scale technology. A further step was the development and construction of a boiler with super-critical steam parameters and increased output. In 2002 the Polish utility Poludniowy Koncern Energetyczny SA awarded a contract to Foster Wheeler Energia Oy to erect a fluidised bed boiler for the Lagisza power plant. Construction of the 460 MW plant was started in 2006. The plant has been in commercial operation since 2009. (orig.)

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)

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.

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.

Use of Neural Networks for modeling and predicting boiler's operating performance

International Nuclear Information System (INIS)

Kljajić, Miroslav; Gvozdenac, Dušan; Vukmirović, Srdjan

2012-01-01

The need for high boiler operating performance requires the application of improved techniques for the rational use of energy. The analysis presented is guided by an effort to find possibilities for ways energy resources can be used wisely to secure a more efficient final energy supply. However, the biggest challenges are related to the variety and stochastic nature of influencing factors. The paper presents a method for modeling, assessing, and predicting the efficiency of boilers based on measured operating performance. The method utilizes a neural network approach to analyze and predict boiler efficiency and also to discover possibilities for enhancing efficiency. The analysis is based on energy surveys of 65 randomly selected boilers located at over 50 sites in the northern province of Serbia. These surveys included a representative range of industrial, public and commercial users of steam and hot water. The sample covered approximately 25% of all boilers in the province and yielded reliable and relevant results. By creating a database combined with soft computing assistance a wide range of possibilities are created for identifying and assessing factors of influence and making a critical evaluation of practices used on the supply side as a source of identified inefficiency. -- Highlights: ► We develop the model for assessing and predicting efficiency of boilers. ► The method implies the use of Artificial Neural Network approach for analysis. ► The results obtained correspond well to collected and measured data. ► Findings confirm and present good abilities of preventive or proactive approach. ► Analysis reveals and specifies opportunities for increasing efficiency of boilers.

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

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...

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.

Life cycle analysis of small scale pellet boilers characterized by high efficiency and low emissions

International Nuclear Information System (INIS)

Monteleone, B.; Chiesa, M.; Marzuoli, R.; Verma, V.K.; Schwarz, M.; Carlon, E.; Schmidl, C.; Ballarin Denti, A.

2015-01-01

Highlights: • LCA was performed on innovative small scale pellet boilers. • Pellet boilers impacts were compared to oil and natural gas boilers impacts. • Both literature and experimental data were used for life cycle analysis. • The environmental impact due to all life cycle phases was envisaged. • Sensitivity tests evidenced realistic ways for pellet boilers impact reduction. - Abstract: This study focuses on the environmental impact assessment through Life Cycle Analysis (LCA) of two innovative 10 kW pellet boilers. In particular, the second boiler represents a technological evolution of the first one developed to improve its performance in terms of efficiency and environmental impact. For both boilers, emission factors measured during laboratory tests (full load tests and specific load cycle tests representative of real life boiler operation) have been used as input data in the life cycle analysis. The SimaPro software (v.8.0.4.30) was used for the LCA and the ReCiPe Midpoint method (European version H) was chosen to assess the environmental impact of all boilers (according to LCA ISO standards). In addition, the ReCiPe Endpoint method was used to compare the final results of all 5 boilers with literature data. The pelletisation process represented the most relevant share of the overall environmental impact followed by the operational phase, the manufacturing phase and the disposal phase. A sensitivity analysis performed on the most efficient pellet boiler evidenced the variation of the boiler’s environmental impact as a function of PM10 and NO X emission factors with respect to emission factors monitored during boiler full load operation. Moreover, the reduction of the boiler’s weight and the adoption of new electronic components led to a consistent reduction (−18%) of its environmental impact with respect to the previous technology. A second LCA has been carried on for a 15 kW oil boiler, a 15 kW natural gas boiler and a 15 kW pellet boiler

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.

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

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)

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.

NOvel Refractory Materials for High Alkali, High Temperature Environments

Energy Technology Data Exchange (ETDEWEB)

Hemrick, J.G.; Griffin, R. (MINTEQ International, Inc.)

2011-08-30

Refractory materials can be limited in their application by many factors including chemical reactions between the service environment and the refractory material, mechanical degradation of the refractory material by the service environment, temperature limitations on the use of a particular refractory material, and the inability to install or repair the refractory material in a cost effective manner or while the vessel was in service. The objective of this project was to address the need for new innovative refractory compositions by developing a family of novel MgO-Al2O3 spinel or other similar magnesia/alumina containing unshaped refractory composition (castables, gunnables, shotcretes, etc) utilizing new aggregate materials, bond systems, protective coatings, and phase formation techniques (in-situ phase formation, altered conversion temperatures, accelerated reactions, etc). This family of refractory compositions would then be tailored for use in high-temperature, highalkaline industrial environments like those found in the aluminum, chemical, forest products, glass, and steel industries. A research team was formed to carry out the proposed work led by Oak Ridge National Laboratory (ORNL) and was comprised of the academic institution Missouri University of Science and Technology (MS&T), and the industrial company MINTEQ International, Inc. (MINTEQ), along with representatives from the aluminum, chemical, glass, and forest products industries. The two goals of this project were to produce novel refractory compositions which will allow for improved energy efficiency and to develop new refractory application techniques which would improve the speed of installation. Also methods of hot installation were sought which would allow for hot repairs and on-line maintenance leading to reduced process downtimes and eliminating the need to cool and reheat process vessels.

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...

Refractory Materials for Flame Deflector Protection System Corrosion Control: Refractory Ceramics Literature Survey

Science.gov (United States)

Calle, Luz Marina; Hintze, Paul E.; Parlier, Christopher R.; Curran, Jerome P.; Kolody, Mark; Perusich, Stephen; Whitten, Mary C.; Trejo, David; Zidek, Jason; Sampson, Jeffrey W.;

Refractory vasculitis

NARCIS (Netherlands)

Rutgers, Bram; Kallenberg, Cees G. M.

Refractory vasculitis occurs in 4-5% of patients with anti-neutrophil cytoplasmic antibody associated vasculitis (AAV). Differences between therapies used for refractory disease are mostly reflected in the percentages of complete and partial remissions, but also in the number of serious side

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.

Improving boiler unit performance using an optimum robust minimum-order observer

Energy Technology Data Exchange (ETDEWEB)

Moradi, Hamed; Bakhtiari-Nejad, Firooz [Energy and Control Centre of Excellence, Department of Mechanical Engineering, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

2011-03-15

To achieve a good performance of the utility boiler, dynamic variables such as drum pressure, steam temperature and water level of drum must be controlled. In this paper, a linear time invariant (LTI) model of a boiler system is considered in which the input variables are feed-water and fuel mass rates. Due to the inaccessibility of some state variables of boiler system, a minimum-order observer is designed based on Luenberger's model to gain an estimate state x of the true state x. Low cost of design and high accuracy of states estimation are the main advantages of the minimum-order observer; in comparison with previous designed full-order observers. By applying the observer on the closed-loop system, a regulator system is designed. Using an optimal functional code developed in MATLAB environment, desired observer poles are found such that suitable time response specifications of the boiler system are achieved and the gain and phase margin values are adjusted in an acceptable range. However, the real dynamic model may associate with parametric uncertainties. In that case, optimum region of poles of observer-based controller are found such that the robust performance of the boiler system against model uncertainties is guaranteed. (author)

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...

Bio boiler - Control conditions. Part 1: Model development and analysis of operating conditions; Biokedel - Reguleringsmaessige forhold. Del 1: Modeludvikling og analyse af dynamiske driftsforhold

Energy Technology Data Exchange (ETDEWEB)

Boecher Poulsen, K.; Christensen, Torkild; Mortensen, Jan; Runge Kristoffersen, J.; Kristmundsson, E. [Tech-wise A/S (Denmark); Moekbak, T.; Mortensen, Hans Peter [Elsam A/S (Denmark)

2002-12-15

This report focuses on the model-building part of the PSO project, 'Control Conditions Bio-boiler'. In the project, which treats dynamic simulation of biomass fired power plants via the MMS software, a certain number of straw/wood chip modules have been built, together with a combustion module which, when connected to the existing MMS modules, can be used for dynamic simulation. Furthermore, a certain number of continuous and discrete components have been built which, together with the remaining MMS modules will create a complete model of the active part of the control structure under the most common operation conditions. By means of the developed straw, combustion and control modules, a model of Enstedvaerket's bio-boiler is built (without wood chip super-heater), including practically all auxiliary control mechanisms. In the report the primary problems caused by the development of the model are discussed, typically numerical problems. First of all it is discussed how a steady state condition can be reached from a nonphysical condition at the start-up of the simulation. After reaching a steady state condition at full load, the boiler load is reduced by adjusting the desired live steam flow setpoint value and the load gradient (as it would be done from the control room). While reducing to part load, one straw line is closed down, as it would be done in 'real life'. From part load, the boiler load is once again in the same way increased to full. (BA) The simulation results are then compared to measurements made on the same boiler during load reduction and load increase.

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

A comprehensive corrosion research project consisting of pilot-scale combustion testing and long-term laboratory corrosion study has been successfully performed. A pilot-scale combustion facility available at Brigham Young University was selected and modified to enable burning of pulverized coals under the operating conditions typical for advanced coal-fired utility boilers. Eight United States (U.S.) coals were selected for this investigation, with the test conditions for all coals set to have the same heat input to the combustor. In addition, the air/fuel stoichiometric ratio was controlled so that staged combustion was established, with the stoichiometric ratio maintained at 0.85 in the burner zone and 1.15 in the burnout zone. The burner zone represented the lower furnace of utility boilers, while the burnout zone mimicked the upper furnace areas adjacent to the superheaters and reheaters. From this staged combustion, approximately 3% excess oxygen was attained in the combustion gas at the furnace outlet. During each of the pilot-scale combustion tests, extensive online measurements of the flue gas compositions were performed. In addition, deposit samples were collected at the same location for chemical analyses. Such extensive gas and deposit analyses enabled detailed characterization of the actual combustion environments existing at the lower furnace walls under reducing conditions and those adjacent to the superheaters and reheaters under oxidizing conditions in advanced U.S. coal-fired utility boilers. The gas and deposit compositions were then carefully simulated in a series of 1000-hour laboratory corrosion tests, in which the corrosion performances of different commercial candidate alloys and weld overlays were evaluated at various temperatures for advanced boiler systems. Results of this laboratory study led to significant improvement in understanding of the corrosion mechanisms operating on the furnace walls as well as superheaters and reheaters in

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.

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...

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

Computational fluid dynamic simulations of coal-fired utility boilers: An engineering tool

Energy Technology Data Exchange (ETDEWEB)

Efim Korytnyi; Roman Saveliev; Miron Perelman; Boris Chudnovsky; Ezra Bar-Ziv [Ben-Gurion University of the Negev, Beer-Sheva (Israel)

2009-01-15

The objective of this study was to develop an engineering tool by which the combustion behavior of coals in coal-fired utility boilers can be predicted. We presented in this paper that computational fluid dynamic (CFD) codes can successfully predict performance of - and emission from - full-scale pulverized-coal utility boilers of various types, provided that the model parameters required for the simulation are properly chosen and validated. For that purpose we developed a methodology combining measurements in a 50 kW pilot-scale test facility with CFD simulations using the same CFD code configured for both test and full-scale furnaces. In this method model parameters of the coal processes are extracted and validated. This paper presents the importance of the validation of the model parameters which are used in CFD codes. Our results show very good fit of CFD simulations with various parameters measured in a test furnace and several types of utility boilers. The results of this study demonstrate the viability of the present methodology as an effective tool for optimization coal burning in full-scale utility boilers. 41 refs., 9 figs., 3 tabs.

Response properties of the refractory auditory nerve fiber.

Science.gov (United States)

Miller, C A; Abbas, P J; Robinson, B K

2001-09-01

The refractory characteristics of auditory nerve fibers limit their ability to accurately encode temporal information. Therefore, they are relevant to the design of cochlear prostheses. It is also possible that the refractory property could be exploited by prosthetic devices to improve information transfer, as refractoriness may enhance the nerve's stochastic properties. Furthermore, refractory data are needed for the development of accurate computational models of auditory nerve fibers. We applied a two-pulse forward-masking paradigm to a feline model of the human auditory nerve to assess refractory properties of single fibers. Each fiber was driven to refractoriness by a single (masker) current pulse delivered intracochlearly. Properties of firing efficiency, latency, jitter, spike amplitude, and relative spread (a measure of dynamic range and stochasticity) were examined by exciting fibers with a second (probe) pulse and systematically varying the masker-probe interval (MPI). Responses to monophasic cathodic current pulses were analyzed. We estimated the mean absolute refractory period to be about 330 micros and the mean recovery time constant to be about 410 micros. A significant proportion of fibers (13 of 34) responded to the probe pulse with MPIs as short as 500 micros. Spike amplitude decreased with decreasing MPI, a finding relevant to the development of computational nerve-fiber models, interpretation of gross evoked potentials, and models of more central neural processing. A small mean decrement in spike jitter was noted at small MPI values. Some trends (such as spike latency-vs-MPI) varied across fibers, suggesting that sites of excitation varied across fibers. Relative spread was found to increase with decreasing MPI values, providing direct evidence that stochastic properties of fibers are altered under conditions of refractoriness.

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...

Ash fouling monitoring and key variables analysis for coal fired power plant boiler

Directory of Open Access Journals (Sweden)

Shi Yuanhao

2015-01-01

Full Text Available Ash deposition on heat transfer surfaces is still a significant problem in coal-fired power plant utility boilers. The effective ways to deal with this problem are accurate on-line monitoring of ash fouling and soot-blowing. In this paper, an online ash fouling monitoring model based on dynamic mass and energy balance method is developed and key variables analysis technique is introduced to study the internal behavior of soot-blowing system. In this process, artificial neural networks (ANN are used to optimize the boiler soot-blowing model and mean impact values method is utilized to determine a set of key variables. The validity of the models has been illustrated in a real case-study boiler, a 300MW Chinese power station. The results on same real plant data show that both models have good prediction accuracy, while the ANN model II has less input parameters. This work will be the basis of a future development in order to control and optimize the soot-blowing of the coal-fired power plant utility boilers.

Engineering and economic aspects of centalized heating from nuclear boilers

International Nuclear Information System (INIS)

Emel'yanov, I.Ya.; Baturov, B.B.; Korytnikov, V.P.; Koryakin, Yu.I.; Chernyaev, V.A.; Kovylyanskij, Ya.A.; Galaktionov, I.V.

1979-01-01

Some engineering and economic aspects for deployment of centralized nuclear boilers (NB) in the USSR are considered. Engineering, maintenance and economic features of NB as compared to organic-fuelled boilers and nuclear thermal power plants are discussed. Among major factors governing economic efficiency of NB underlined are oraganic fuel costs, reactor unit power, location relative to heat-consuming centres and capacity factor. It is concluded that NB can be economical for heating large consumers (more than 1500 G kal/hr). At the periphery NB can be competitive already at reactor unit power of several MWth. The development of HTGR type reactor-based nuclear-chemical boilers and lines for heat transport in a chemically bound state (e.g., CH 4 → H 2 +CO 2 +CO → CH 4 ) opens the way for a substantial breakthrow in the centralized NB efficiency

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

Experimental investigation on a 0.35 MWth coal-fired horizontal circulating fluidized bed boiler

Energy Technology Data Exchange (ETDEWEB)

Meng, Aihong; Li, Qinghai; Zhang, Yanguo; Wang, Zhaojun; Dang, Wenda [Tsinghua Univ., Beijing (China); Ministry of Education, Beijing (China). Key Lab. for Thermal Science and Power Engineering

2013-07-01

The capacities of industrial coal-fired boilers are normally less than 20-30 MWe. And these coal-fired boilers of low capacity are facing the severe situation of low efficiency and heavy environmental pollution. Hence, an innovative horizontal circulating fluidized bed (HCFB) boiler was developed to enhance heat efficiency and reduce pollutant emission of industrial boilers in China. The chamber in the HCFB boiler consists of primary combustion chamber, secondary combustion chamber and burnout chamber, which were combined horizontally side by side. To verify the conception of horizontal fluidized circulation and to obtain the characteristic data, a 0.35 MWth coal-combustion HCFB boiler was designed and installed to perform some experiments of combustion and mass circulation. In the boiler there were two mass circulating paths, one is inner circulating through the inertia separator and another was external circulating through the cyclone separator. The connection bottom of the secondary chamber and the burnout chamber was designed as an inertia separator, in which separated and collected solid materials were returned to the primary combustion. In fact the secondary separator was a small cyclone separator connecting to the exit of the burnout chamber. Heat efficiency and separating efficiency of the experimental boiler were measured and analyzed. Furthermore, mass and temperature distribution along the chambers height were also investigated. The results showed that the heat efficiency of the bare boiler was 82%. The mass balance based on ash content was measured and analyzed. Separating efficiency of the inertia separator and cyclone separator was 60 and 99.9%, respectively. It showed that the two stage material separation and circulation enhanced coal combustion in the HCFB boiler and help to minimize the height of the furnace.

Thermal and Performance Analysis of a Gasification Boiler and Its Energy Efficiency Optimization

Directory of Open Access Journals (Sweden)

Jan Valíček

2017-07-01

Full Text Available The purpose of this study was to determine a method for multi-parametric output regulation of a gasification boiler especially designed for heating or for hot water heating in buildings. A new method of regulation is offered, namely more parametric regulation via proportional-integral-derivative (PID controllers that are capable of controlling the calculated values of pressure, temperature and fan speed. These values of pressure, temperature and fan speed are calculated in a completely new way, and calculations of setpoints for determination of optimal parameters lead to an increase in boilers efficiency and power output. Results of measurements show that changes at the mouth of the stack draft due atmospheric influences occur in times with high intensity and high frequency, while power parameters, or boiler power output amplitudes and fan speed automatically “copy” those changes proportionally due to instantaneous fan speed changes. The proposed method of regulation of the gasification boiler power output according to the technical solution enables a simple, cheap, express and continuous maintenance of high power output at low concentrations of the exhaust gases of the gasification boilers from the viewpoint of the boiler user, as well as from the perspective of development and production it allows a continuous control monitoring of these parameters.

Pharmacotherapy for Refractory and Super-Refractory Status Epilepticus in Adults.

Science.gov (United States)

Holtkamp, Martin

2018-03-01

Patients with prolonged seizures that do not respond to intravenous benzodiazepines and a second-line anticonvulsant suffer from refractory status epilepticus and those with seizures that do not respond to continuous intravenous anesthetic anticonvulsants suffer from super-refractory status epilepticus. Both conditions are associated with significant morbidity and mortality. A strict pharmacological treatment regimen is urgently required, but the level of evidence for the available drugs is very low. Refractory complex focal status epilepticus generally does not require anesthetics, but all intravenous non-anesthetizing anticonvulsants may be used. Most descriptive data are available for levetiracetam, phenytoin and valproate. Refractory generalized convulsive status epilepticus is a life-threatening emergency, and long-term clinical consequences are eminent. Administration of intravenous anesthetics is mandatory, and drugs acting at the inhibitory gamma-aminobutyric acid (GABA) A receptor such as midazolam, propofol and thiopental/pentobarbital are recommended without preference for one of those. One in five patients with anesthetic treatment does not respond and has super-refractory status epilepticus. With sustained seizure activity, excitatory N-methyl-d-aspartate (NMDA) receptors are increasingly expressed post-synaptically. Ketamine is an antagonist at this receptor and may prove efficient in some patients at later stages. Neurosteroids such as allopregnanolone increase sensitivity at GABA A receptors; a Phase 1/2 trial demonstrated safety and tolerability, but randomized controlled data failed to demonstrate efficacy. Adjunct ketogenic diet may contribute to termination of difficult-to-treat status epilepticus. Randomized controlled trials are needed to increase evidence for treatment of refractory and super-refractory status epilepticus, but there are multiple obstacles for realization. Hitherto, prospective multicenter registries for pharmacological

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)

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.

Boiler: lossy compression of RNA-seq alignments using coverage vectors.

Science.gov (United States)

Pritt, Jacob; Langmead, Ben

2016-09-19

We describe Boiler, a new software tool for compressing and querying large collections of RNA-seq alignments. Boiler discards most per-read data, keeping only a genomic coverage vector plus a few empirical distributions summarizing the alignments. Since most per-read data is discarded, storage footprint is often much smaller than that achieved by other compression tools. Despite this, the most relevant per-read data can be recovered; we show that Boiler compression has only a slight negative impact on results given by downstream tools for isoform assembly and quantification. Boiler also allows the user to pose fast and useful queries without decompressing the entire file. Boiler is free open source software available from github.com/jpritt/boiler. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

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...

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...

7 CFR 51.2833 - U.S. No. 1 Boilers.

Science.gov (United States)

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false U.S. No. 1 Boilers. 51.2833 Section 51.2833 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards...) Grades § 51.2833 U.S. No. 1 Boilers. U.S. No. 1 Boilers consists of onions which meet all the...

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...

Online Monitoring System of Air Distribution in Pulverized Coal-Fired Boiler Based on Numerical Modeling

Directory of Open Access Journals (Sweden)

Żymełka Piotr

2017-12-01

Full Text Available Balanced distribution of air in coal-fired boiler is one of the most important factors in the combustion process and is strongly connected to the overall system efficiency. Reliable and continuous information about combustion airflow and fuel rate is essential for achieving optimal stoichiometric ratio as well as efficient and safe operation of a boiler. Imbalances in air distribution result in reduced boiler efficiency, increased gas pollutant emission and operating problems, such as corrosion, slagging or fouling. Monitoring of air flow trends in boiler is an effective method for further analysis and can help to appoint important dependences and start optimization actions. Accurate real-time monitoring of the air distribution in boiler can bring economical, environmental and operational benefits. The paper presents a novel concept for online monitoring system of air distribution in coal-fired boiler based on real-time numerical calculations. The proposed mathematical model allows for identification of mass flow rates of secondary air to individual burners and to overfire air (OFA nozzles. Numerical models of air and flue gas system were developed using software for power plant simulation. The correctness of the developed model was verified and validated with the reference measurement values. The presented numerical model for real-time monitoring of air distribution is capable of giving continuous determination of the complete air flows based on available digital communication system (DCS data.

Online Monitoring System of Air Distribution in Pulverized Coal-Fired Boiler Based on Numerical Modeling

Science.gov (United States)

Żymełka, Piotr; Nabagło, Daniel; Janda, Tomasz; Madejski, Paweł

2017-12-01

Balanced distribution of air in coal-fired boiler is one of the most important factors in the combustion process and is strongly connected to the overall system efficiency. Reliable and continuous information about combustion airflow and fuel rate is essential for achieving optimal stoichiometric ratio as well as efficient and safe operation of a boiler. Imbalances in air distribution result in reduced boiler efficiency, increased gas pollutant emission and operating problems, such as corrosion, slagging or fouling. Monitoring of air flow trends in boiler is an effective method for further analysis and can help to appoint important dependences and start optimization actions. Accurate real-time monitoring of the air distribution in boiler can bring economical, environmental and operational benefits. The paper presents a novel concept for online monitoring system of air distribution in coal-fired boiler based on real-time numerical calculations. The proposed mathematical model allows for identification of mass flow rates of secondary air to individual burners and to overfire air (OFA) nozzles. Numerical models of air and flue gas system were developed using software for power plant simulation. The correctness of the developed model was verified and validated with the reference measurement values. The presented numerical model for real-time monitoring of air distribution is capable of giving continuous determination of the complete air flows based on available digital communication system (DCS) data.

SRC burn test in 700-hp oil-designed boiler. Annex Volume C. Boiler emission report. Final technical report

Energy Technology Data Exchange (ETDEWEB)

1983-09-01

The Solvent-Refined Coal (SRC) test burn program was conducted at the Pittsburgh Energy Technology Center (PETC) located in Bruceton, Pa. One of the objectives of the study was to determine the feasibility of burning SRC fuels in boilers set up for fuel oil firing and to characterize emissions. Testing was conducted on the 700-hp oil-fired boiler used for research projects. No. 6 fuel oil was used for baseline data comparison, and the following SRC fuels were tested: SRC Fuel (pulverized SRC), SRC Residual Oil, and SRC-Water Slurry. Uncontrolled particulate emission rates averaged 0.9243 lb/10/sup 6/ Btu for SRC Fuel, 0.1970 lb/10/sup 6/ Btu for SRC Residual Oil, and 0.9085 lb/10/sup 6/ Btu for SRC-Water Slurry. On a lb/10/sup 6/ Btu basis, emissions from SRC Residual Oil averaged 79 and 78%, respectively, lower than the SRC Fuel and SRC-Water Slurry. The lower SRC Residual Oil emissions were due, in part, to the lower ash content of the oil and more efficient combustion. The SRC Fuel had the highest emission rate, but only 2% higher than the SRC-Water Slurry. Each fuel type was tested under variable boiler operating parameters to determine its effect on boiler emissions. The program successfully demonstrated that the SRC fuels could be burned in fuel oil boilers modified to handle SRC fuels. This report details the particulate emission program and results from testing conducted at the boiler outlet located before the mobile precipitator take-off duct. The sampling method was EPA Method 17, which uses an in-stack filter.

Implementation of the EU directive on the energy performance of buildings: Development of the Latvian Scheme for energy auditing of buildings and inspection of boilers. Project document

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

'Development of the Latvian Scheme for energy auditing of buildings and inspection of boilers' includes major steps in implementing the EU EPB directive in Latvia. The EPB directive includes a number of efforts: 1. A methodology for calculation of the integrated energy performance of buildings 2. Application of minimum requirements on the energy performance for new buildings 3. Application of minimum requirements on the energy performance for larger existing buildings subject to major renovation 4. Energy performance certification (energy labelling) of buildings 5. Regular inspection of boilers and of air-conditioning systems in buildings, and assessment of heating installations in older systems. The present project includes activities connected to point 4 and point 5. The results will include 4 steps in implementing the EU EPB directive: 1) A Latvian training of certified independent energy auditors to be active conducting energy audits and issuing energy performance certificates. Including a handbook in energy auditing. 2) A Latvian training of certified independent experts for inspection of boilers, air-con systems and assessing older heating systems. Including a handbook in boiler inspection. 3) A proposal for the institutional set-up for a connected scheme for energy auditing and a scheme for boiler inspection 4) Initial information on the scheme of energy auditors and of the boiler inspection. (au)

46 CFR 62.35-20 - Oil-fired main boilers.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Oil-fired main boilers. 62.35-20 Section 62.35-20... AUTOMATION Requirements for Specific Types of Automated Vital Systems § 62.35-20 Oil-fired main boilers. (a) General. (1) All main boilers, regardless of intended mode of operation, must be provided with the...

Development of a pellet boiler with Stirling engine for m-CHP domestic application

Energy Technology Data Exchange (ETDEWEB)

Crema, Luigi; Alberti, Fabrizio; Bertaso, Alberto; Bozzoli, Alessandro [Fondazione Bruno Kessler (FBK), Povo, Trento (IT). Renewable Energies and Environmental Technologies Unit (REET)

2011-12-15

A new sustainable technology has been designed by Fondazione Bruno Kessler through its unit Renewable Energies and Environmental Technologies. This technology is realized integrating in a single system (1) a Stirling engine (mRT-1K) from a pre-engineering design of Allan J. Organ; (2) a micro-heat exchanger technology, to reduce the net transfer unit deficit on the hot side of the heat engine; (3) a customized pellet boiler, able to extract electrical and thermal power; and (4) a customized hydraulic circuit, connecting the cool side of the Stirling engine and the heat generation on the second section of the pellet boiler. The objective of this paper was to present a new technology for the micro-cogeneration of energy at a distributed level able to be integrated in domestic dwellings. Most part of the available biomass is used in buildings for the generation of thermal power for indoor heating and, in minor cases, for hot sanitary water. In the Province of Trento, 88% of the biomass is used for this purpose. The full system is actually under integration for the test phase and not yet tested. The first tests on the single components have confirmed preliminary results on the Stirling engine with respect to the tolerances, pressurization, and proper integration of the electrical generator-driven control system. The pellet boiler has been tested separately, confirming an overall thermal efficiency of 90%. (orig.)

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...

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)

Slagging in a pulverised-coal-fired boiler

Energy Technology Data Exchange (ETDEWEB)

Devir, G.P.; Pohl, J.H.; Creelman, R.A. [University of Queensland, St. Lucia, Qld. (Australia). Dept. of Chemical Engineering

2000-07-01

This paper describes a technique to evaluate the severity of slagging of a coal in a pulverised-coal-fired boiler. There are few data in the literature on the nature of in-situ boiler slags, their rate of growth and/or their strength properties relevant to sootblowing. The latter is thought to be of more concern to boiler operators and gives rise to the significance of selecting suitable strength tests. As well as standardised methods for characterising pulverised coal performance in a boiler, several novel and less popular techniques are discussed in detail. A suite of three sub-bituminous coals from the Callide Coalfields, Biloela (600 km north of Brisbane), has been selected for slagging tests in the 350 MW{sub e} units of Callide 'B' power station. Disposable air-cooled mild steel slagging probes have been constructed to simulate the conditions for deposit formation in the boiler region. To date, tests for one of these coals has been completed and preliminary results are presented. Once testing for the remaining coals has been completed, it is anticipated that the differences exhibited in deposit growth and strength may be correlated with typical variations in physical and chemical properties of the pulverised coal.

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

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...

Co-firing of coal with biomass and waste in full-scale suspension-fired boilers

Energy Technology Data Exchange (ETDEWEB)

Dam-Johansen, Kim; Frandsen, Flemming J.; Jensen, Peter A.; Jensen, Anker D. [Technical Univ. of Denmark, Lyngby (Denmark). Dept. of chemical and Biochemical Engineering

2013-07-01

The energy policy in Denmark has for many years focused on lowering the net CO{sub 2} emission from heat and power production by replacing fossil fuels by renewable resources. This has been done by developing dedicated grate-fired boilers for biomass and waste fuels but also by developing coal-based suspension-fired boilers to accept still higher fractions of biomass or waste material as fuels. This last development has been challenging of many reasons, including pre-treatment of fuels, and solving potential emission and operational problems during the simultaneous development of supercritical steam cycles with steam temperatures close to 600 C, providing power efficiencies close to 50% (Hein KRG, Sustainable energy supply and environment protection - strategies, resources and technologies. In: Gupta R, Wall T, Hupa M, Wigley F, Tillman D, Frandsen FJ (eds) Proceedings of international conference on impact of fuel quality on power production and the environment, Banff Conference Centre, Banff, Alberta, Canada, 29 Sept-4 Oct, 2008). For 25 years the CHEC (Combustion and Harmful Emission Control) Research Centre at DTU Chemical Engineering, has attained a leading role in research, supporting power producing industry, plant owners and boiler manufacturers to optimize design and operation and minimize cost and environmental impact using alternative fuels in suspension fired boilers. Our contribution has been made via a combination of full-scale measuring campaigns, pilot-scale studies, lab-scale measurements and modeling tools. The research conducted has addressed many issues important for co-firing, i.e. fuel processing, ash induced boiler deposit formation and corrosion, boiler chamber fuel conversion and emission formation, influence on flue gas cleaning equipment and the utilization of residual products. This chapter provides an overview of research activities, aiming at increasing biomass shares during co-firing in suspension, conducted in close collaboration with

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

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,

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.

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

Autoradiographic study of corrosion of refractories

International Nuclear Information System (INIS)

Lisenenkova, S.B.; Kucheryavyi, M.N.; Bursteva, T.A.

1988-01-01

A comparative study was made of the character of the interaction between a container-glass melt consisting of sodium calcium silicate and refractories in various furnace sections using an autoradiographic method. Static tests were conducted on specimens of the following refractories: chrome-aluminum-zircon, Bakor 41, corundum, a high alumina refractory, and a refractory based on tin dioxide. The specimens were activated by calcium 45. Autoradiography and photomicrography indicated that an intrinsic feature of all refractories was that calcium from the melt penetrated the refractories along the weak link; for fused-cast refractories, the glass phase; and for sintered refractories, through the binder and cracks

Refractory alloy technology for space nuclear power applications

International Nuclear Information System (INIS)

Cooper, R.H. Jr.; Hoffman, E.E.

1984-01-01

Purpose of this symposium is twofold: (1) to review and document the status of refractory alloy technology for structural and fuel-cladding applications in space nuclear power systems, and (2) to identify and document the refractory alloy research and development needs for the SP-100 Program in both the short and the long term. In this symposium, an effort was made to recapture the space reactor refractory alloy technology that was cut off in midstream around 1973 when the national space nuclear reactor program began in the early 1960s, was terminated. The six technical areas covered in the program are compatibility, processing and production, welding and component fabrication, mechanical and physical properties, effects of irradiation, and machinability. The refractory alloys considered are niobium, molybdenum, tantalum, and tungsten. Thirteen of the 14 pages have been abstracted separately. The remaining paper summarizes key needs for further R and D on refractory alloys

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)

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

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...

Tungsten and refractory metals 3, proceedings

International Nuclear Information System (INIS)

Bose, A.; Dowding, R.J.

1996-01-01

The Third International Conference on Tungsten and Refractory Metals was held in Greater Washington DC at the McLean Hilton, McLean Virginia, on November 15--16, 1995. This meeting was the third in a series of conferences held in the Washington DC area. The first meeting was in 1992 and was entitled ''International Conference on Tungsten and Tungsten Alloys.'' In 1994, the scope of the meeting was expanded to include other refractory metals such as molybdenum, iridium, rhenium, tantalum and niobium. The tremendous success of that meeting was the primary motivation for this Conference. The broader scope (the inclusion of other refractory metals and alloys) of the Conference was kept intact for this meeting. In fact, it was felt that the developments in the technology of these materials required a common forum for the interchange of current research information. The papers presented in this meeting examined the rapid advancements in the technology of refractory metals, with special emphasis on the processing, structure, and properties. Among the properties there was emphasis on both quasi-static and dynamic rates. Another topic that received considerable interest was the area of refractory carbides and tungsten-copper composites. One day of concurrent session was necessary to accommodate all of the presentations

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)

A NOx control regulation for electric utility boilers in California

International Nuclear Information System (INIS)

Price, D.R.

1992-01-01

The reduction of oxides of nitrogen emissions is becoming an increasingly important part of ozone attainment plans. As a part of its ozone attainment plan, the Ventura County (California) Air Pollution Control Board adopted in June, 1991, a regulation (Rule 59) to limit oxides of nitrogen emissions from four electrical utility boilers in the county. Rule development took two years and involved considerable public input. The emission limit for each of two 750 megawatt units is set at 0.10 pounds of NO x per megawatt-hour net after June, 1994. The emission limit for each of two 215 megawatt units is 0.20 pounds of NO x per megawatt-hour after June, 1996. Additional limitations are included for fuel oil operation. The rule does not specify an emission control technology. Conventional selective catalytic reduction, urea injection and combustion modifications are considered the technologies most likely to be used to comply. At $17,613 per ton of NO x reduced for the two large boilers and $8.992 per ton of NO x reduced for the small boilers, the rule is considered cost effective. The capital cost for conventional selective catalytic reduction systems on all four boilers is expected to be in excess of $210,000,000

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 ...

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

Simulation of pulverized coal fired boiler: reaction chamber

Energy Technology Data Exchange (ETDEWEB)

Rodrigues, C.P.; Lansarin, M.A.; Secchi, A.R.; Mendes, T.F. [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Dept. de Engenharia Quimica. Grupo de Modelagem, Simulacao, Controle e Otimizacao de Processos)]. E-mail: {cperdomo, marla, arge, talita}@enq.ufrgs.br

2005-06-15

This work is part of a joint project to built a computational tool for power plant simulation, dealing specifically with the reaction chamber (place of the boiler where the fuel is burned). In order to describe the conversion of chemical energy to thermal energy, an one dimensional pseudo-homogeneous mathematical model, with variable physical properties, and based on mass and energy balances, was developed. The equations were implemented in the gPROMS simulator and the model parameters were estimated using the module gEST of this software, with experimental data from a large-scale coal-fired utility boiler and kinetic data from the open literature. The results showed that the model predicts the composition of the outlet combustion gas satisfactorily. (author)

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 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...

Application of ELD and load forecast in optimal operation of industrial boiler plants equipped with thermal stores

International Nuclear Information System (INIS)

Cao Jiacong

2007-01-01

Optimal operation of industrial boiler plants with objects of high energy efficiency and low fuel cost is still well worth investigating when energy problem becomes a world's concern, for there are a great number of boiler plants serving industries. The optimization of operation is a measure that is less expensive and easier to carry out than many other measures. Economic load dispatch (ELD) is an effective approach to optimal operation of industrial boiler plants. In the paper a newly developed method referred to as the method of minimum-departure model (MDM) is used in the ELD for boiler plants. It is more convenient for carrying out ELD when boiler plants are equipped with thermal energy stores that usually adopt the working mode of optimal segmentation of a daily load curve. In the case of industrial boiler plants, ELD needs a prerequisite, viz., the accurate load forecast, which is performed using artificial neural networks in this paper. A computer program for the optimal operation was completed and applied to an example, which results the minimum daily fuel cost of the whole boiler plant

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

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

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.

Static stability characteristics of the boilers at Oldbury nuclear power station

International Nuclear Information System (INIS)

Paynter, R.J.; Rea, J.

1986-01-01

The cause of an intermittent load loss at Oldbury Nuclear Power Station is shown to be the high sensitivity of boiler performance to the imposed spatial distribution of boiler gas inlet temperature. This high sensitivity is demonstrated to be a function of the inherent static stability characteristics of the boilers. The installation of orifice plates with a high flow resistance into the feed pipework to the half boilers has greatly reduced the boiler sensitivity and eliminated the intermittent load loss so that, on average, higher electrical generation is obtained from the station. (author)

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)

Applied Gaussian Process in Optimizing Unburned Carbon Content in Fly Ash for Boiler Combustion

Directory of Open Access Journals (Sweden)

Chunlin Wang

2017-01-01

Full Text Available Recently, Gaussian Process (GP has attracted generous attention from industry. This article focuses on the application of coal fired boiler combustion and uses GP to design a strategy for reducing Unburned Carbon Content in Fly Ash (UCC-FA which is the most important indicator of boiler combustion efficiency. With getting rid of the complicated physical mechanisms, building a data-driven model as GP is an effective way for the proposed issue. Firstly, GP is used to model the relationship between the UCC-FA and boiler combustion operation parameters. The hyperparameters of GP model are optimized via Genetic Algorithm (GA. Then, served as the objective of another GA framework, the predicted UCC-FA from GP model is utilized in searching the optimal operation plan for the boiler combustion. Based on 670 sets of real data from a high capacity tangentially fired boiler, two GP models with 21 and 13 inputs, respectively, are developed. In the experimental results, the model with 21 inputs provides better prediction performance than that of the other. Choosing the results from 21-input model, the UCC-FA decreases from 2.7% to 1.7% via optimizing some of the operational parameters, which is a reasonable achievement for the boiler combustion.

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.

High Efficiency - Reduced Emissions Boiler Systems for Steam, Heat, and Processing

Science.gov (United States)

2012-07-01

enable energy saving necessary for obtaining Energy Star certification for the whole boiler system. Widespread boiler control updates could be possible...adaptability to different boiler and oil/gas burner configurations, and extensibility to operation with nonconventional fuels (e.g., biogas and syngas...typically operating below or slightly above 80%. Higher efficiency improvements can certainly be obtained via boiler replacement and adoption of

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.

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.

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.

Refractory alloy technology for space nuclear power applications

Energy Technology Data Exchange (ETDEWEB)

Cooper, R.H. Jr.; Hoffman, E.E. (eds.)

1984-01-01

Purpose of this symposium is twofold: (1) to review and document the status of refractory alloy technology for structural and fuel-cladding applications in space nuclear power systems, and (2) to identify and document the refractory alloy research and development needs for the SP-100 Program in both the short and the long term. In this symposium, an effort was made to recapture the space reactor refractory alloy technology that was cut off in midstream around 1973 when the national space nuclear reactor program began in the early 1960s, was terminated. The six technical areas covered in the program are compatibility, processing and production, welding and component fabrication, mechanical and physical properties, effects of irradiation, and machinability. The refractory alloys considered are niobium, molybdenum, tantalum, and tungsten. Thirteen of the 14 pages have been abstracted separately. The remaining paper summarizes key needs for further R and D on refractory alloys. (DLC)

Coal-fired boiler houses in Cracow present state and possibilities to improve their efficiency

Energy Technology Data Exchange (ETDEWEB)

Cyklis, P. [Institute of Industrial Equipment and Power Engineering, Cracow (Poland); Butcher, T.A. [Brookhaven National Lab., Upton, NY (United States)

1995-12-31

A significant amount of heat energy both for heating and process purposes is generated in Cracow, Poland in small-and medium size local boiler houses. The operating procedure of these boiler houses is most often economically and ecologically ineffective because of the bad condition of boilers and lack of funds to install automation, control and measurement equipment. Within the Polish-American Program of Elimination of Low Emission Sources financed by the US Department of Energy, the ENERGOEKSPERT Co., Ltd. investigated chosen boiler houses in Cracow, commissioned by the Cracow Development Office. The results of these investigations were subject of engineering analysis carried out at the Institute of Industrial Equipment and Power Engineering, Technical University, Cracow. The analysis proved that the low-cost improvement of economic efficiency and reduction of air pollutant emission is feasible for combustion of coal fuels.

Optimization of Boiler Control for Improvement of Load Following Capabilities of Existing Power Plants

DEFF Research Database (Denmark)

Mortensen, J. H.; Mølbak, T.; Pedersen, Tom Søndergaard

1997-01-01

An An optimizing control system for improving the load following capabilities of power plant units has been developed. The system is implemented as a complement producing additive control signals to the existing boiler control system, a concept which has various practical advantages in terms...... of implementation and commissioning. The optimizing control system takes into account the multivariable and nonlinear characteristics of the boiler process as a gain-scheduled LQG-controller is utilized. Simulation results indicate that a reduction of steam temperature deviations of about 75% can be obtained.......optimizing control system for improving the load following capabilities of power plant units has been developed. The system is implemented as a complement producing additive control signals to the existing boiler control system, a concept which has various practical advantages in terms of implementation...

NOx Control Options and Integration for US Coal Fired Boilers

Energy Technology Data Exchange (ETDEWEB)

Mike Bockelie; Marc Cremer; Kevin Davis; Martin Denison; Adel Sarofim; Connie Senior; Hong-Shig Shim; Dave Swenson; Bob Hurt; Eric Suuberg; Eric Eddings; Kevin Whitty; Larry Baxter; Calvin Bartholomew; William Hecker

2006-06-30

This is the Final Report for DOE Cooperative Agreement No: DE-FC26-00NT40753. The goal of the project was 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) provided co-funding for this program. This project included research on: (1) In furnace NOx control; (2) Impacts of combustion modifications on boiler operation; (3) Selective Catalytic Reduction (SCR) catalyst testing and (4) Ammonia adsorption/removal on fly ash. Important accomplishments were achieved in all aspects of the project. Rich Reagent Injection (RRI), an in-furnace NOx reduction strategy based on injecting urea or anhydrous ammonia into fuel rich regions in the lower furnace, was evaluated for cyclone-barrel and PC fired utility boilers. Field tests successfully demonstrated the ability of the RRI process to significantly reduce NOx emissions from a staged cyclone-fired furnace operating with overfire air. The field tests also verified the accuracy of the Computational Fluid Dynamic (CFD) modeling used to develop the RRI design and highlighted the importance of using CFD modeling to properly locate and configure the reagent injectors within the furnace. Low NOx firing conditions can adversely impact boiler operation due to increased waterwall wastage (corrosion) and increased soot production. A corrosion monitoring system that uses electrochemical noise (ECN) corrosion probes to monitor, on a real-time basis, high temperature corrosion events within the boiler was evaluated. Field tests were successfully conducted at two plants. The Ohio Coal Development Office provided financial assistance to perform the field tests. To investigate soot behavior, an advanced model to predict soot production and destruction was implemented into an existing reacting CFD modeling tool. Comparisons between experimental data collected

Bubbling fluidized bed boiler for Vanaja power plant

Energy Technology Data Exchange (ETDEWEB)

Sormunen, R.; Haermae, P.; Vessonen, K.; Ketomaeki, A. [ed.

1998-07-01

At the Vanaja Power Plant, on the outskirts of Haemeenlinna, there have been changes which reflect the central goals in IVO`s product development work. At Vanaja, efficiency is combined with environmental friendliness. In the early 1980s, the plant was modernized to produce district heat in addition to electricity. At that time, along with the new gas turbine at the plant, the main fuel, coal, while remaining the fuel for the old boilers, was replaced by natural gas. This year a new type of bubbling fluidized bed boiler enabling continuous use of peat and trial use of biofuels along with coal was introduced at the plant. In addition to the Nordic countries, this kind of technology is required in central eastern Europe, where modernization of ageing power plants is being planned to achieve the best possible solutions in respect of production and the environment. IVO develops a new repair technique for underwater sites

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

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

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

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.

Improved Recovery Boiler Performance Through Control of Combustion, Sulfur, and Alkali Chemistry

Energy Technology Data Exchange (ETDEWEB)

Baxter, Larry L.

2008-06-09

This project involved the following objectives: 1. Determine black liquor drying and devolatilization elemental and total mass release rates and yields. 2. Develop a public domain physical/chemical kinetic model of black liquor drop combustion, including new information on drying and devolatilization. 3. Determine mechanisms and rates of sulfur scavenging in recover boilers. 4. Develop non-ideal, public-domain thermochemistry models for alkali salts appropriate for recovery boilers 5. Develop data and a one-dimensional model of a char bed in a recovery boiler. 6. Implement all of the above in comprehensive combustion code and validate effects on boiler performance. 7. Perform gasification modeling in support of INEL and commercial customers. The major accomplishments of this project corresponding to these objectives are as follows: 1. Original data for black liquor and biomass data demonstrate dependencies of particle reactions on particle size, liquor type, gas temperature, and gas composition. A comprehensive particle submodel and corresponding data developed during this project predicts particle drying (including both free and chemisorbed moisture), devolatilization, heterogeneous char oxidation, char-smelt reactions, and smelt oxidation. Data and model predictions agree, without adjustment of parameters, within their respective errors. The work performed under these tasks substantially exceeded the original objectives. 2. A separate model for sulfur scavenging and fume formation in a recovery boiler demonstrated strong dependence on both in-boiler mixing and chemistry. In particular, accurate fume particle size predictions, as determined from both laboratory and field measurements, depend on gas mixing effects in the boilers that lead to substantial particle agglomeration. Sulfur scavenging was quantitatively predicted while particle size required one empirical mixing factor to match data. 3. Condensed-phase thermochemistry algorithms were developed for salt

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

Emissions from three wood-fired domestic central heating boilers - heat load dependence

International Nuclear Information System (INIS)

Karlsson, M.L.

1992-01-01

The flue gases from three wood-fired domestic central heating boilers have been characterized. Measurements were made at three part loads; 3, 7 and 15 kW. Two of the boilers were modern multi-fuel boilers, with inverse firing and natural draught. The third boiler was a single-fuel wood boiler, with inverse firing and combustion air supply through a fan. All boilers were environmentally approved; the tar emissions were below 30 mg/MJ at nominal heat load. The following parameters were measured: - CO, CO 2 , NO x , total hydrocarbons (THC), - tar and particulates, - twelve volatile organic compounds (VOC). The limit value for tar emission was heavily exceeded for all three boilers at the part loads at which they were tested. For the two multi-fuel boilers the tar emissions decreased with increasing load level, while the opposite was found for the wood boiler with a fan. The NO x emissions varied between 20 and 120 mg/MJ. The multi-fuel boilers showed increasing NO x emissions with increasing heat load. The single-fuel wood boiler showed NO x emissions at about 60 mg/MJ, independent of load level. The CO and THC levels in general were high. The CO levels varied between 1000 and 2000 mg/MJ. While the THC levels varied between 300 and 4000 mg/MJ. Broadly speaking, the CO and THC levels decreased with increasing load levels for the multi-fuel boilers. For the single-fuel wood boiler the CO and THC levels were roughly the same at all load levels. Out of the twelve VOC compounds which were measured, the following could be detected and quantified. With FTIR analysis: Methane, ethylene, propene and acetylene. With GC analysis: Methanol, phenol and acetic acid. (1 ref., 31 figs., 7 tabs.)

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

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)

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

Cofiring of biofuels in coal fired boilers: Results of case study analysis

Energy Technology Data Exchange (ETDEWEB)

Tillman, D.A. [Ebasco Environmental, Sacramento, CA (United States); Hughes, E. [Electric Power Research Institute, Palo Alto, CA (United States); Gold, B.A. [TVA, Chattanooga, TN (United States)

1993-12-31

Ebasco Environmental and Reaction Engineering, under contract to EPRI, performed a case study analysis of cofiring biomass in coal-fired boilers of the Tennessee Valley Authority (TVA). The study was also sponsored by DOE. This analysis included evaluating wood fuel receiving, preparation, and combustion in pulverized coal (PC) boilers and cyclone furnaces and an assessment of converting wood into pyrolysis oil or low Btu gas for use in a new combined cycle combustion turbine (CCCT) installation. Cofiring wood in existing coal-fired boilers has the most immediate potential for increasing the utilization of biofuels in electricity generation. Cofiring biofuels with coal can potentially generate significant benefits for utilities including: (1) reducing emissions of SO{sub 2} and NO{sub x}; (2) reducing the net emissions of CO{sub 2}; (3) potentially reducing the fuel cost to the utility depending upon local conditions and considering biomass is potentially exempt from the proposed Btu tax and may get a 1.5 cent/kWh credit for energy generated by wood combustion; (4) supporting local industrial forest industry; and (5) providing a long term market for the development of a biofuel supply and delivery industry. Potential benefits are reviewed in the context of cofiring biofuel at a rate of 15% heat input to the boiler, and compares this cofiring strategy and others previously tested or developed by other utilities. Other issues discussed include: (1) wood fuel specifications as a function of firing method; (2) wood fuel receiving and preparation system requirements; (3) combustion system requirements for cofiring biofuels with coal; (4) combustion impacts of firing biofuels with coal; (5) system engineering issues; (6) the economics of cofiring biofuel with coal. The Allen, TN 330 MW(e) cyclone boiler and Kingston, TN 135 MW(e) Boiler {number_sign}1, a tangentially fired PC unit, case studies are then summarized in the paper, highlighting the cofiring opportunities.

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.

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

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)

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

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.

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...

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...

Gas chromatographic determination of residual hydrazine and morpholine in boiler feed water and steam condensates

International Nuclear Information System (INIS)

Vatsala, S.; Bansal, V.; Tuli, D.K.; Rai, M.M.; Jain, S.K.; Srivastava, S.P.; Bhatnagar, A.K.

1994-01-01

Hydrazine, an oxygen scavenger in boiler water, was derivatised to the corresponding acetone azine and determined at the ng ml -1 level by gas chromatography. Morpholine, a corrosion inhibitor used in steam boilers, was estimated either directly (if >2.0 μg ml -1 ) or by quantitative preconcentration (0.1 ng-2.0 μg ml -1 ). To obtain symmetrical peaks for these amines, the column packing was coated with KOH. Use of a nitrogen-specific detector improved accuracy of estimation of hydrazine and morpholine, giving a RSD of 1.9-3.6%. Chromatographic analysis of these amines in boiler feed water and steam condensate samples collected from boilers servicing a pertroleum refinery is described. Environmental safety regulations calls for monitoring of hydrazine and the methods developed can easily be adapted for this purpose. (orig.)

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.)

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...

Exergy analysis on industrial boiler energy conservation and emission evaluation applications

Science.gov (United States)

Li, Henan

2017-06-01

Industrial boiler is one of the most energy-consuming equipments in china, the annual consumption of energy accounts for about one-third of the national energy consumption. Industrial boilers in service at present have several severe problems such as small capacity, low efficiency, high energy consumption and causing severe pollution on environment. In recent years, our country in the big scope, long time serious fog weather, with coal-fired industrial boilers is closely related to the regional characteristics of high strength and low emissions [1]. The energy-efficient and emission-reducing of industry boiler is of great significance to improve China’s energy usage efficiency and environmental protection. Difference in thermal equilibrium theory is widely used in boiler design, exergy analysis method is established on the basis of the first law and second law of thermodynamics, by studying the cycle of the effect of energy conversion and utilization, to analyze its influencing factors, to reveal the exergy loss of location, distribution and size, find out the weak links, and a method of mining system of the boiler energy saving potential. Exergy analysis method is used for layer combustion boiler efficiency and pollutant emission characteristics analysis and evaluation, and can more objectively and accurately the energy conserving potential of the mining system of the boiler, find out the weak link of energy consumption, and improve equipment performance to improve the industrial boiler environmental friendliness.

46 CFR 97.15-15 - Examination of boilers and machinery.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Examination of boilers and machinery. 97.15-15 Section... VESSELS OPERATIONS Tests, Drills, and Inspections § 97.15-15 Examination of boilers and machinery. It shall be the duty of the chief engineer when assuming charge of the boilers and machinery of a vessel to...

46 CFR 32.35-1 - Boilers and machinery-TB/ALL.

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Boilers and machinery-TB/ALL. 32.35-1 Section 32.35-1 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY TANK VESSELS SPECIAL EQUIPMENT, MACHINERY, AND HULL REQUIREMENTS Main and Auxiliary Machinery § 32.35-1 Boilers and machinery—TB/ALL. Boilers, main and auxiliary...

46 CFR 78.17-30 - Examination of boilers and machinery.

Science.gov (United States)

2010-10-01

... 46 Shipping 3 2010-10-01 2010-10-01 false Examination of boilers and machinery. 78.17-30 Section... OPERATIONS Tests, Drills, and Inspections § 78.17-30 Examination of boilers and machinery. It shall be the duty of the chief engineer when assuming charge of the boilers and machinery of a vessel to examine...

46 CFR 63.25-3 - Electric hot water supply boilers.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Electric hot water supply boilers. 63.25-3 Section 63.25... water supply boilers. (a) Electric hot water supply boilers that have a capacity not greater than 454... section except the periodic testing required by paragraph (j) of this section. Electric hot water supply...

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.

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)

Multi-objective Optimization of Coal-fired Boiler Combustion Based on NSGA-II

OpenAIRE

Tingfang Yu; Hongzhen Zhu; Chunhua Peng

2013-01-01

NOx emission characteristics and overall heat loss model for a 300MW coal-fired boiler were established by Back Propagation (BP) neural network, by which the the functional relationship between outputs (NOx emissions & overall heat loss of the boiler) and inputs (operational parameters of the boiler) of a coal-fired boiler can be predicted. A number of field test data from a full-scale operating 300MWe boiler were used to train and verify the BP model. The NOx emissions & heat loss pr...

Characteristics of particulate-bound polycyclic aromatic hydrocarbons emitted from industrial grade biomass boilers.

Science.gov (United States)

Yang, Xiaoyang; Geng, Chunmei; Sun, Xuesong; Yang, Wen; Wang, Xinhua; Chen, Jianhua

2016-02-01

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic or mutagenic and are important toxic pollutants in the flue gas of boilers. Two industrial grade biomass boilers were selected to investigate the characteristics of particulate-bound PAHs: one biomass boiler retro-fitted from an oil boiler (BB1) and one specially designed (BB2) biomass boiler. One coal-fired boiler was also selected for comparison. By using a dilution tunnel system, particulate samples from boilers were collected and 10 PAH species were analyzed by gas chromatography-mass spectrometry (GC-MS). The total emission factors (EFs) of PAHs ranged from 0.0064 to 0.0380 mg/kg, with an average of 0.0225 mg/kg, for the biomass boiler emission samples. The total PAH EFs for the tested coal-fired boiler were 1.8 times lower than the average value of the biomass boilers. The PAH diagnostic ratios for wood pellets and straw pellets were similar. The ratio of indeno(1,2,3-cd)pyrene/[indeno(1,2,3-cd)pyrene+benzo(g,h,i)perylene] for the two biomass boilers was lower than those of the reference data for other burning devices, which can probably be used as an indicator to distinguish the emission of biomass boilers from that of industrial coal-fired boilers and residential stoves. The toxic potential of the emission from wood pellet burning was higher than that from straw pellet burning, however both of them were much lower than residential stove exhausts. Copyright © 2015. Published by Elsevier B.V.

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

2004-03-31

This is the fifteenth Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT40753. 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. At AEP's Gavin Plant, data from the corrosion probes showed that corrosion rate increased as boiler load was increased. During an outage at the plant, the drop in boiler load, sensor temperature and corrosion rate could all be seen clearly. Restarting the boiler saw a resumption of corrosion activity. This behavior is consistent with previous observations made at a 600MWe utility boiler. More data are currently being examined for magnitudes of corrosion rates and changes in boiler operating conditions. Considerable progress was made this quarter in BYU's laboratory study of catalyst deactivation. Surface sulfation appears to partially suppress NO adsorption when the catalyst is not exposed to NH3; NH3 displaces surface-adsorbed NO on SCR catalysts and surface sulfation increases the amount of adsorbed NH3, as confirmed by both spectroscopy and TPD experiments. However, there is no indication of changes in catalyst activity despite changes in the amount of adsorbed NH3. A monolith test reactor (MTR), completed this quarter, provided the first comparative data for one of the fresh and field-exposed monolith SCR catalysts yet developed in this project. Measurements of activity on one of the field-exposed commercial monolith catalysts do not show significant changes in catalyst activity (within experimental error) as compared to the fresh catalyst. The exposed surface of the sample contains large amounts of Ca and Na, neither of which is present in the fresh sample, even after removal of visibly obvious fouling deposits. However, these fouling compounds do

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

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

46 CFR 196.15-15 - Examination of boilers and machinery.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Examination of boilers and machinery. 196.15-15 Section... VESSELS OPERATIONS Test, Drills, and Inspections § 196.15-15 Examination of boilers and machinery. (a) It shall be the duty of the chief engineer when he assumes charge of the boilers and machinery of a vessel...

Refractory Research Group - U.S. DOE, Albany Research Center [Institution Profile

Energy Technology Data Exchange (ETDEWEB)

Bennett, James P.

2004-09-01

The refractory research group at the Albany Research Center (ARC) has a long history of conducting materials research within the U.S. Bureau of Mines, and more recently, within the U.S. Dept. of Energy. When under the U.S. Bureau of Mines, research was driven by national needs to develop substitute materials and to conserve raw materials. This mission was accomplished by improving refractory material properties and/or by recycling refractories using critical and strategic materials. Currently, as a U.S. Dept of Energy Fossil Energy field site, research is driven primarily by the need to assist DOE in meeting its vision to develop economically and environmentally viable technologies for the production of electricity from fossil fuels. Research at ARC impacts this vision by: • Providing information on the performance characteristics of materials being specified for the current generation of power systems; • Developing cost-effective, high performance materials for inclusion in the next generation of fossil power systems; and • Solving environmental emission and waste problems related to fossil energy systems. A brief history of past refractory research within the U.S. Bureau of Mines, the current refractory research at ARC, and the equipment and capabilities used to conduct refractory research at ARC will be discussed.

Statistical experimental design for refractory coatings

International Nuclear Information System (INIS)

McKinnon, J.A.; Standard, O.C.

2000-01-01

The production of refractory coatings on metal casting moulds is critically dependent on the development of suitable rheological characteristics, such as viscosity and thixotropy, in the initial coating slurry. In this paper, the basic concepts of mixture design and analysis are applied to the formulation of a refractory coating, with illustration by a worked example. Experimental data of coating viscosity versus composition are fitted to a statistical model to obtain a reliable method of predicting the optimal formulation of the coating. Copyright (2000) The Australian Ceramic Society

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)

Development of METHANE de-NOX Reburn Process for Wood Waste and Biomass Fired Stoker Boilers - Final Report - METHANE de-NOX Reburn Technology Manual

Energy Technology Data Exchange (ETDEWEB)

J. Rabovitser; B. Bryan; S. Wohadlo; S. Nester; J. Vaught; M. Tartan (Gas Technology Institute); R. Glickert (ESA Environmental Solutions)

2007-12-31

The overall objective of this project was to demonstrate the effectiveness of the METHANE de-NOX® (MdN) Reburn process in the Forest Products Industry (FPI) to provide more efficient use of wood and sludge waste (biosolids) combustion for both energy generation and emissions reduction (specifically from nitrogen oxides (NOx)) and to promote the transfer of the technology to the wide range of wood waste-fired stoker boilers populating the FPI. This document, MdN Reburn Commercial Technology Manual, was prepared to be a resource to promote technology transfer and commercialization activities of MdN in the industry and to assist potential users understand its application and installation requirements. The Manual includes a compilation of MdN commercial design data from four different stoker boiler designs that were baseline tested as part of the development effort. Design information in the Manual include boiler CFD model studies, process design protocols, engineering data sheets and commercial installation drawings. Each design package is unique and implemented in a manner to meet specific mill requirements.

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 ...

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.

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.

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

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...

Methodology for identifying parameters for the TRNSYS model Type 210 - wood pellet stoves and boilers

Energy Technology Data Exchange (ETDEWEB)

Persson, Tomas; Fiedler, Frank; Nordlander, Svante

2006-05-15

This report describes a method how to perform measurements on boilers and stoves and how to identify parameters from the measurements for the boiler/stove-model TRNSYS Type 210. The model can be used for detailed annual system simulations using TRNSYS. Experience from measurements on three different pellet stoves and four boilers were used to develop this methodology. Recommendations for the set up of measurements are given and the required combustion theory for the data evaluation and data preparation are given. The data evaluation showed that the uncertainties are quite large for the measured flue gas flow rate and for boilers and stoves with high fraction of energy going to the water jacket also the calculated heat rate to the room may have large uncertainties. A methodology for the parameter identification process and identified parameters for two different stoves and three boilers are given. Finally the identified models are compared with measured data showing that the model generally agreed well with measured data during both stationary and dynamic conditions.

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...

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

Deposit Probe Measurements in Danish Grate and Pulverized Fuel Biomass Power Boilers

DEFF Research Database (Denmark)

Hansen, Stine Broholm; Jensen, Peter Arendt; Jappe Frandsen, Flemming

2012-01-01

. Corresponding samples of fuels, ash deposits and fly ash have provided information on the transformation of inorganics in the boiler. Generally, grate fired boilers provide a fly ash containing high contents of K, Cl and S compared to the fuel ash, while suspension fired boilers fly ash has a composition nearly...... similar to the fuel ash. Inner most biomass deposits are always salt-rich, while thicker deposit layers also contain some Si and Ca. Deposit probe formation rate measurements have been performed in different ways on several boilers. Grate and suspension fired boilers seems to cause similar deposit...... formation rates. Suspension fired boilers generate more fly ash, while grate boilers form a fly ash with a higher fraction of melt formation (and thereby a higher sticking probability) at similar temperatures. For suspension fired units it is observed that wood with a lower ash content than straw gives rise...

[Emission characteristics of PM10 from coal-fired industrial boiler].

Science.gov (United States)

Li, Chao; Li, Xing-Hua; Duan, Lei; Zhao, Meng; Duan, Jing-Chun; Hao, Ji-Ming

2009-03-15

Through ELPI (electrical low-pressure impactor) based dilution sampling system, the emission characteristics of PM10 and PM2.5 was studied experimentally at the inlet and outlet of dust catchers at eight different coal-fired industrial boilers. Results showed that a peak existed at around 0.12-0.20 microm of particle size for both number size distribution and mass size distribution of PM10 emitted from most of the boilers. Chemical composition analysis indicated that PM2.5 was largely composed of organic carbon, elementary carbon, and sulfate, with mass fraction of 3.7%-21.4%, 4.2%-24.6%, and 1.5%-55.2% respectively. Emission factors of PM10 and PM2.5 measured were 0.13-0.65 kg x t(-1) and 0.08-0.49 kg x t(-1) respectively for grate boiler using raw coal, and 0.24 kg x t(-1) and 0.22 kg x t(-1) for chain-grate boiler using briquette. In comparison, the PM2.5 emission factor of fluidized bed boiler is 1.14 kg x t(-1), much her than that of grate boiler. Due to high coal consumption and low efficiency of dust separator, coal-fired industrial boiler may become the most important source of PM10, and should be preferentially controlled in China.

Analysis of a waste-heat boiler by CFD simulation

Energy Technology Data Exchange (ETDEWEB)

Yang, Yongziang; Jokilaakso, A. [Helsinki Univ. of Technology, Otaniemi (Finland)

1996-12-31

Waste-heat boilers play important roles in the continuous operation of a smelter and in the conservation of energy. However, the fluid flow and heat transfer behaviour has not been well studied, concerning the boiler performance and design. This presentation describes simulated gas flow and heat transfer of a waste-heat boiler in the Outokumpu copper flash smelting process. The governing transport equations for the conservation of mass, momentum and enthalpy were solved with a commercial CFD-code PHOENICS. The standard k-{epsilon} turbulence model and a composite-flux radiation model were used in the computations. The computational results show that the flow is strongly recirculating and distinctly three-dimensional in most part of the boiler, particularly in the radiation section. The predicted flow pattern and temperature distribution were in a good agreement with laboratory models and industrial measurements. The results provide detailed information of flow pattern, the temperature distribution and gas cooling efficiency. The CFD proved to be a useful tool in analysing the boiler operation. (author)

Analysis of a waste-heat boiler by CFD simulation

Energy Technology Data Exchange (ETDEWEB)

Yang, Yongziang; Jokilaakso, A [Helsinki Univ. of Technology, Otaniemi (Finland)

1997-12-31

Waste-heat boilers play important roles in the continuous operation of a smelter and in the conservation of energy. However, the fluid flow and heat transfer behaviour has not been well studied, concerning the boiler performance and design. This presentation describes simulated gas flow and heat transfer of a waste-heat boiler in the Outokumpu copper flash smelting process. The governing transport equations for the conservation of mass, momentum and enthalpy were solved with a commercial CFD-code PHOENICS. The standard k-{epsilon} turbulence model and a composite-flux radiation model were used in the computations. The computational results show that the flow is strongly recirculating and distinctly three-dimensional in most part of the boiler, particularly in the radiation section. The predicted flow pattern and temperature distribution were in a good agreement with laboratory models and industrial measurements. The results provide detailed information of flow pattern, the temperature distribution and gas cooling efficiency. The CFD proved to be a useful tool in analysing the boiler operation. (author)

Electrostatic precipitator performance and trace element emissions from two Kraft recovery boilers.

Science.gov (United States)

Lind, Terttaliisa; Hokkinen, Jouni; Jokiniemi, Jorma K; Hillamo, Risto; Makkonen, Ulla; Raukola, Antti; Rintanen, Jaakko; Saviharju, Kari

2006-01-15

Fine particle emissions from combustion sources have gained attention recently due to their adverse effects on human health. The emission depends on the combustion process, fuel, and particulate removal technology. Particle concentrations at Kraft recovery boiler exits are very high, and the boilers are typically equipped with electrostatic precipitators (ESP). However, little data are available on the ESP performance in recovery boilers. Particle concentrations and size distributions were determined at two modern, operating recovery boilers. In addition, we determined the fractional collection efficiency of the ESPs by simultaneous measurements at the ESP inlet and outlet and the particulate emissions of trace metals. The particle mass concentration atthe ESP inlet was 11-24 g/Nm3 at the two boilers. Particle emissions were 30-40 mg/ Nm3 at boiler A and 12-15 mg/Nm3 at boiler B. The particle size distributions had a major particle mode at around 1 microm. These fume particles contained most of the particle mass. The main components in the particles were sodium and sulfate with minor amounts of chloride, potassium, and presumably some carbonate. The ESP collection efficiency was 99.6-99.8% at boiler A and 99.9% at boiler B. The particle penetration through the ESP was below 0.6% in the entire fume particle size range of 0.3-3 microm. Trace element emissions from both boilers were well below the limit values set by EU directive for waste incineration.

Novel partial-subsidence tower-type boiler design in an ultra-supercritical power plant

International Nuclear Information System (INIS)

Xu, Gang; Xu, Cheng; Yang, Yongping; Fang, Yaxiong; Zhou, Luyao; Zhang, Kai

2014-01-01

Highlights: • The two-pass type and tower-type boilers were compared. • A novel partial-subsidence tower-type boiler design was proposed. • Thermodynamic and economic analyses were quantitatively conducted. • The application of the partial-subsidence boiler to a 700 °C stage unit was further analyzed. - Abstract: An increasing number of tower-type boilers have been applied to ultra-supercritical power plants because of the simple design of the membrane walls and the smooth increase in temperature of such boilers. Nevertheless, the significant height and long steam pipelines of this boiler type will expand the power plant investment cost and increase steam-side pressure losses, especially for higher parameters units requiring high costs of nickel-based alloy materials. Thus, a novel partial-subsidence tower-type boiler design was proposed. In this boiler type, nearly 1/2–2/3 of the boiler height was embedded underground to reduce the height of the boiler and the length of the steam pipelines significantly. Thermodynamic and economic analyses were conducted on a state-of-the-art 1000 MW ultra-supercritical power plant and a prospective 700 °C-stage double reheat power plant. Results showed that the proposed tower-type boiler design could result in a 0.1% point increase in net efficiency and a $0.56/MW h reduction in the cost of electricity in a 1000 MW power plant. This economic benefit was enhanced for power plants with higher steam parameters and larger capacity. The concept of the proposed boiler design may provide a promising method for tower-type boiler applications, especially in new-generation double reheat plants with higher parameters

Hydronic Heating Retrofits for Low-Rise Multifamily Buildings: Boiler Control Replacement and Monitoring

Energy Technology Data Exchange (ETDEWEB)

Dentz, J.; Henderson, H.; Varshney, K.

2014-09-01

The ARIES Collaborative, a U.S. Department of Energy Building America research team, partnered with NeighborWorks America affiliate Homeowners' Rehab Inc. (HRI) of Cambridge, Massachusetts, to study improvements to the central hydronic heating system in one of the nonprofit's housing developments. The heating controls in the three-building, 42-unit Columbia Cambridge Alliance for Spanish Tenants housing development were upgraded. Fuel use in the development was excessive compared to similar properties. A poorly insulated thermal envelope contributed to high energy bills, but adding wall insulation was not cost-effective or practical. The more cost-effective option was improving heating system efficiency. Efficient operation of the heating system faced several obstacles, including inflexible boiler controls and failed thermostatic radiator valves. Boiler controls were replaced with systems that offer temperature setbacks and one that controls heat based on apartment temperature in addition to outdoor temperature. Utility bill analysis shows that post-retrofit weather-normalized heating energy use was reduced by 10%-31% (average of 19%). Indoor temperature cutoff reduced boiler runtime (and therefore heating fuel consumption) by 28% in the one building in which it was implemented. Nearly all savings were obtained during night which had a lower indoor temperature cut off (68 degrees F) than day (73 degrees F). This implies that the outdoor reset curve was appropriately adjusted for this building for daytime operation. Nighttime setback of heating system supply water temperature had no discernable impact on boiler runtime or gas bills.

CFD simulation of the combustion process of the low-emission vortex boiler

Science.gov (United States)

Chernov, A. A.; Maryandyshev, P. A.; Pankratov, E. V.; Lubov, V. K.

2017-11-01

Domestic heat and power engineering needs means and methods for optimizing the existing boiler plants in order to increase their technical, economic and environmental work. The development of modern computer technology, methods of numerical modeling and specialized software greatly facilitates the solution of many emerging problems. CFD simulation allows to obtaine precise results of thermochemical and aerodynamic processes taking place in the furnace of boilers in order to optimize their operation modes and develop directions for their modernization. The paper presents the results of simulation of the combustion process of a low-emission vortex coal boiler of the model E-220/100 using the software package Ansys Fluent. A hexahedral grid with a number of 2 million cells was constructed for the chosen boiler model. A stationary problem with a two-phase flow was solved. The gaseous components are air, combustion products and volatile substances. The solid phase is coal particles at different burnup stages. The Euler-Lagrange approach was taken as a basis. Calculation of the coal particles trajectories was carried out using the Discrete Phase Model which distribution of the size particle of coal dust was accounted for using the Rosin-Rammler equation. Partially Premixed combustion model was used as the combustion model which take into account elemental composition of the fuel and heat analysis. To take turbulence into account, a two-parameter k-ε model with a standard wall function was chosen. Heat transfer by radiation was calculated using the P1-approximation of the method of spherical harmonics. The system of spatial equations was numerically solved by the control volume method using the SIMPLE algorithm of Patankar and Spaulding. Comparison of data obtained during the industrial-operational tests of low-emission vortex boilers with the results of mathematical modeling showed acceptable convergence of the tasks of this level, which confirms the adequacy of the

Dynamic simulation of a circulating fluidized bed boiler system part II: Simulation of a boiler system operating in a power plant

International Nuclear Information System (INIS)

Kim, Seong Il; Choi, Sang Min; Yang, Jong In

2016-01-01

A case of dynamic performance simulation model of a CFB boiler is presented in this study. The dynamic system of a CFB boiler in an operating power plant and the transient behavior of sub-models is described in the accompanying paper, Part I. The current paper, Part II, describes the model extension for the CFB boiler system in a power plant. The open loop model in Paper I was expanded by applying a set of PID (Proportional-integral-differential) control loops. In the control loop, pressure, temperature, mass flow rate of the main steam, the drum water level and the oxygen level at the stack were controlled. Dynamic performance was simulated to check the response of the closed control loop. Finally, performance of the total boiler system for a range of operation load of the power plant was simulated, where the parameters were calculated and control variables were maintained at the set values by PID control. Dynamic performance of a boiler at a selected load variation case was simulated and compared with actual measurements and their transient response characteristics were discussed. The simulation can also directly produce useful operation parameters, which are not measurable, but could be used for engineering evaluation

Dynamic simulation of a circulating fluidized bed boiler system part II: Simulation of a boiler system operating in a power plant

Energy Technology Data Exchange (ETDEWEB)

Kim, Seong Il; Choi, Sang Min; Yang, Jong In [Dept. of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Daejeon(Korea, Republic of)

2016-12-15

A case of dynamic performance simulation model of a CFB boiler is presented in this study. The dynamic system of a CFB boiler in an operating power plant and the transient behavior of sub-models is described in the accompanying paper, Part I. The current paper, Part II, describes the model extension for the CFB boiler system in a power plant. The open loop model in Paper I was expanded by applying a set of PID (Proportional-integral-differential) control loops. In the control loop, pressure, temperature, mass flow rate of the main steam, the drum water level and the oxygen level at the stack were controlled. Dynamic performance was simulated to check the response of the closed control loop. Finally, performance of the total boiler system for a range of operation load of the power plant was simulated, where the parameters were calculated and control variables were maintained at the set values by PID control. Dynamic performance of a boiler at a selected load variation case was simulated and compared with actual measurements and their transient response characteristics were discussed. The simulation can also directly produce useful operation parameters, which are not measurable, but could be used for engineering evaluation.

46 CFR 167.25-1 - Boilers, pressure vessels, piping and appurtenances.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Boilers, pressure vessels, piping and appurtenances. 167... SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Marine Engineering § 167.25-1 Boilers, pressure vessels, piping and... the following standards for boilers, pressure vessels, piping and appurtenances: (1) Marine...

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,...

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.

An analysis of the thermodynamic efficiency for exhaust gas recirculation-condensed water recirculation-waste heat recovery condensing boilers (EGR-CWR-WHR CB)

International Nuclear Information System (INIS)

Lee, Chang-Eon; Yu, Byeonghun; Lee, Seungro

2015-01-01

This study presents fundamental research on the development of a new boiler that is expected to have a higher efficiency and lower emissions than existing boilers. The thermodynamic efficiency of exhaust gas recirculation-condensed water recirculation-waste heat recovery condensing boilers (EGR-CWR-WHR CB) was calculated using thermodynamic analysis and was compared with other boilers. The results show the possibility of obtaining a high efficiency when the temperature of the exhaust gas is controlled within 50–60 °C because water in the exhaust gas is condensed within this temperature range. In addition, the enthalpy emitted by the exhaust gas for the new boiler is smaller because the amount of condensed water is increased by the high dew-point temperature and the low exhaust gas temperature. Thus, the new boiler can obtain a higher efficiency than can older boilers. The efficiency of the EGR-CWR-WHR CB proposed in this study is 93.91%, which is 7.04% higher than that of existing CB that is currently used frequently. - Highlights: • The study presents the development of a new boiler expected to have a high efficiency. • Thermodynamic efficiency of EGR-CWR-WHR condensing boiler was calculated. • Efficiency of EGR-CWR-WHR CB is 93.91%, which is 7.04% higher than existing CB

Process technology - rare and refractory metals

International Nuclear Information System (INIS)

Gupta, C.K.; Bose, D.K.

1989-01-01

India has fairly rich resreves of rare and refractory metals. Abundant sources of ilmenite, rutile, zircon and rare earths are found in the placer deposits of the southern and eastern coasts of the country. Columbite-tantalite occur in mica and the mining belts of Bihar and cassiterite deposits are found in Bastar (Madhya Pradesh). Vanadium as a minor associate occurs in bauxites and in the vast deposits of titaniferrous magnetites. Over the years, research and development and pilot plant works in many research organisations in India have built up a sound technological base in the country for process metallurgy of many refractory and rare earth metals starting from their indigenous sources. The present paper provides a comprehensive view of the developments that have taken place till now on the processing of various refractory and rare earth metals with particular reference to the extensive work carried out at the Department of Atomic Energy. The coverage includes mineral benification separation of individual elements, preparation of pure intermediates, techniques of reduction to metal and final purification. The paper also reviews some of the recent developments that have been taken place in these fields and the potential application of these metals in the foreseeable future. (author). 22 refs., 18 fi g., 7 tabs

Real-time monitoring energy efficiency and performance degradation of condensing boilers

NARCIS (Netherlands)

Baldi, S.; Le, Q.T.; Holub, O.; Endel, P

2017-01-01

Condensing boilers achieve higher efficiency than traditional boilers by using waste heat in flue gases to preheat cold return water entering the boiler. Water vapor produced during combustion is condensed into liquid form, thus recovering its latent heat of vaporization, leading to around 10–12%

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.

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.

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.

Refractoriness in human atria

DEFF Research Database (Denmark)

Skibsbye, Lasse; Jespersen, Thomas; Christ, Torsten

2016-01-01

BACKGROUND: Refractoriness of cardiac cells limits maximum frequency of electrical activity and protects the heart from tonic contractions. Short refractory periods support major arrhythmogenic substrates and augmentation of refractoriness is therefore seen as a main mechanism of antiarrhythmic...... drugs. Cardiomyocyte excitability depends on availability of sodium channels, which involves both time- and voltage-dependent recovery from inactivation. This study therefore aims to characterise how sodium channel inactivation affects refractoriness in human atria. METHODS AND RESULTS: Steady......-state activation and inactivation parameters of sodium channels measured in vitro in isolated human atrial cardiomyocytes were used to parameterise a mathematical human atrial cell model. Action potential data were acquired from human atrial trabeculae of patients in either sinus rhythm or chronic atrial...

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.

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.

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...

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...

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...

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)

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...

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...

Development and evaluation of SUS 304H — IN 617 welds for advanced ultra supercritical boiler applications

International Nuclear Information System (INIS)

Pavan, A.H.V.; Vikrant, K.S.N.; Ravibharath, R.; Singh, Kulvir

2015-01-01

At moderately high temperature sections of Advanced Ultra Super Critical (AUSC) boilers, welding of superalloys to austenitic steels is inevitable owing to economic aspects of boiler. Welding of SUS 304H and Inconel 617 (IN 617) was attempted using IN 617 filler material employing conventional Gas Tungsten Arc Welding (GTAW) process and the procedure was successfully established along with optimized welding parameters. Microstructural characterization was carried out to identify various zones on either side of the fusion boundaries. Unmixed Zone and Heat Affected Zone (HAZ) were observed towards SUS 304H fusion boundary while no distinct HAZ was observed towards IN 617 fusion boundary. Micro-hardness profiling indicated decrease in hardness at the HAZ towards SUS 304H fusion boundary. Mechanical properties evaluation at both ambient and elevated temperatures was carried out and data obtained was compared with those of base metals. The tensile strength of the cross weld specimens at high temperatures were observed to be marginally lower than that of IN 617 but significantly more than that of SUS 304H, hence, tolerable. Stress-rupture properties of the cross-weld specimens as tested in this study were found to be intermediate to the base metals’ data, thus, suitable for AUSC power plants' boiler applications. Hence, this work gives an insight into welding procedure establishment, microstructural development, variation of mechanical properties at elevated temperatures and stress-rupture properties of the dissimilar metal welds at elevated temperatures. - Highlights: • Procedure establishment & parameters optimization for fabricating defect-free welds. • Characterization of various zones formed during welding. • Mechanical properties evaluation and comparison with those of base metals. • Influence of various zones formed during welding on mechanical properties inferred. • Understanding long term behavior of welds at elevated temperatures

Development and evaluation of SUS 304H — IN 617 welds for advanced ultra supercritical boiler applications

Energy Technology Data Exchange (ETDEWEB)

Pavan, A.H.V., E-mail: pavanahv@bhelrnd.co.in [Metallurgy Department, Corporate R& D Division, Bharat Heavy Electricals Limited, Vikasnagar, Hyderabad 500 093 (India); Vikrant, K.S.N., E-mail: vikrant@bhelrnd.co.in [Metallurgy Department, Corporate R& D Division, Bharat Heavy Electricals Limited, Vikasnagar, Hyderabad 500 093 (India); Ravibharath, R., E-mail: rrbharath@bhelrnd.co.in [Welding Research Institute, Bharat Heavy Electricals Limited, Tiruchirapalli 620 014 (India); Singh, Kulvir, E-mail: kulvir@bhelrnd.co.in [Metallurgy Department, Corporate R& D Division, Bharat Heavy Electricals Limited, Vikasnagar, Hyderabad 500 093 (India)

2015-08-26

At moderately high temperature sections of Advanced Ultra Super Critical (AUSC) boilers, welding of superalloys to austenitic steels is inevitable owing to economic aspects of boiler. Welding of SUS 304H and Inconel 617 (IN 617) was attempted using IN 617 filler material employing conventional Gas Tungsten Arc Welding (GTAW) process and the procedure was successfully established along with optimized welding parameters. Microstructural characterization was carried out to identify various zones on either side of the fusion boundaries. Unmixed Zone and Heat Affected Zone (HAZ) were observed towards SUS 304H fusion boundary while no distinct HAZ was observed towards IN 617 fusion boundary. Micro-hardness profiling indicated decrease in hardness at the HAZ towards SUS 304H fusion boundary. Mechanical properties evaluation at both ambient and elevated temperatures was carried out and data obtained was compared with those of base metals. The tensile strength of the cross weld specimens at high temperatures were observed to be marginally lower than that of IN 617 but significantly more than that of SUS 304H, hence, tolerable. Stress-rupture properties of the cross-weld specimens as tested in this study were found to be intermediate to the base metals’ data, thus, suitable for AUSC power plants' boiler applications. Hence, this work gives an insight into welding procedure establishment, microstructural development, variation of mechanical properties at elevated temperatures and stress-rupture properties of the dissimilar metal welds at elevated temperatures. - Highlights: • Procedure establishment & parameters optimization for fabricating defect-free welds. • Characterization of various zones formed during welding. • Mechanical properties evaluation and comparison with those of base metals. • Influence of various zones formed during welding on mechanical properties inferred. • Understanding long term behavior of welds at elevated temperatures.

Analysis of residual swirl in tangentially-fired natural gas-boiler

International Nuclear Information System (INIS)

Hasril Hasini; Muhammad Azlan Muad; Mohd Zamri Yusoff; Norshah Hafeez Shuaib

2010-01-01

This paper describes the investigation on residual swirl flow in a 120 MW natural gas, full-scale, tangential-fired boiler. Emphasis is given towards the understanding of the behavior of the combustion gas flow pattern and temperature distribution as a result of the tangential firing system of the boiler. The analysis was carried out based on three-dimensional computational modeling on full scale boiler with validation from key design parameter as well as practical observation. Actual operating parameters of the actual boiler are taken as the boundary conditions for this modeling. The prediction of total heat flux was found to be in agreement with the key design parameter while the residual swirl predicted at the upper furnace agrees qualitatively with the practical observation. Based on this comparison, detail analysis was carried out for comprehensive understanding on the generation and destruction of the residual swirl behavior in boiler especially those with high capacity. (author)

LCA of a condensing boiler according to EuP Directive

International Nuclear Information System (INIS)

Tremonti, M.; Breedvelt, L.; Padovan, G.; Bosio, S.; Corsini, M.

2008-01-01

In the light of the EuP Directive (2005/32/EC), producers of Energy using Product (EuP) are obliged to initiate eco design activities. Fourteen product groups are currently under study, one being the preparatory EC study Eco Boiler, and will result in a EuP Working Plan. The LCA of a condensing boiler, commissionated by an Italian SME in the Lombardy Region, has been conducted to support its environmental strategy and communication, to start implementing eco design activities and to anticipate implications to the EuP Directive. In line with the Eco Boiler study, no detailed LCA has been applied, instead a simplified LCA proves to be a strategic tool to support the company environmental objectives. Specifically, the condensing boiler (the option with the best environmental performance and the lowest life cycle costs for the final consumer) has been internally compared to other boilers, resulting in useful eco design recommendations

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

Plasma spraying of refractory metals and refractory hard materials. State of the art

International Nuclear Information System (INIS)

Eschnauer, H.; Lugscheider, E.; Jaeger, D.

1989-01-01

Suitable spraying processes for manufacturing refractory metals, refractory hard materials as well as spray materials with refractory components are the VPS- and IPS-spraying techniques. The advantages of these special spraying process variations are described. The reactive spraying materials are systematically organized. The characteristical properties used in purpose of improving the substrate surfaces are explained. Finally some examples of the latest results of research concerning plasma spraying of reactive materials are shown. 16 refs., 10 figs. (Author)

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...

Development of a Refractory High Entropy Superalloy (Postprint)

Science.gov (United States)

2016-03-17

hardened with HfC precipitates [2], Co-Re- or Co-Al-W-based alloys [3] or two-phase ( FCC + L12) refractory superalloys based on platinum group metals...Ni-based superalloys consisting of cuboids with the ordered L12 structure embedded in an FCC solid-solution matrix. Based on this microstructural...and 5). A comparison of the average atomic radii with the measured lattice parameters allows us to conclude that the disordered BCC phase forming

Failure analyses and weld repair of boiler feed water pumps

Energy Technology Data Exchange (ETDEWEB)

Vulpen, R van [KemaPower Generation, Arnhem (Netherlands)

1999-12-31

During a regular inspection of the Boiler Auxiliaries at one of the Dutch Electricity Production Companies serious cracks were found in the cover and casings of the feed water circulation pumps in two units after 108.000 and 122.000 hours of boiler operation. Kema Laboratories carried out Failure analyses on boat samples at the cracked areas. Corrosion fatigue cracking was found on the inner side of the GS-24CrNiMo325 casing. Shop Weld repairs were carried out using a newly developed mechanized Plasma Welding Technique. The repaired feed water circulation pumps showed no problems alter several years of operation. The costs of repair were substantially lower than the costs of replacement. (orig.) 3 refs.

Failure analyses and weld repair of boiler feed water pumps

Energy Technology Data Exchange (ETDEWEB)

Vulpen, R. van [KemaPower Generation, Arnhem (Netherlands)

1998-12-31

During a regular inspection of the Boiler Auxiliaries at one of the Dutch Electricity Production Companies serious cracks were found in the cover and casings of the feed water circulation pumps in two units after 108.000 and 122.000 hours of boiler operation. Kema Laboratories carried out Failure analyses on boat samples at the cracked areas. Corrosion fatigue cracking was found on the inner side of the GS-24CrNiMo325 casing. Shop Weld repairs were carried out using a newly developed mechanized Plasma Welding Technique. The repaired feed water circulation pumps showed no problems alter several years of operation. The costs of repair were substantially lower than the costs of replacement. (orig.) 3 refs.

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...

Techno-economic analysis of wood biomass boilers for the greenhouse industry

International Nuclear Information System (INIS)

Chau, J.; Sowlati, T.; Sokhansanj, S.; Preto, F.; Melin, S.; Bi, X.

2009-01-01

The objective of this study is to perform a techno-economic analysis on a typical wood pellet and wood residue boiler for generation of heat to an average-sized greenhouse in British Columbia. The variables analyzed included greenhouse size and structure, boiler efficiency, fuel types, and source of carbon dioxide (CO 2 ) for crop fertilization. The net present value (NPV) show that installing a wood pellet or a wood residue boiler to provide 40% of the annual heat demand is more economical than using a natural gas boiler to provide all the heat at a discount rate of 10%. For an assumed lifespan of 25 years, a wood pellet boiler system could generate NPV of C$259,311 without electrostatic precipitator (ESP) and C$74,695 with ESP, respectively. While, installing a wood residue boiler with or without an ESP could provide NPV of C$919,922 or C$1,104,538, respectively. Using a wood biomass boiler could also eliminate over 3000 tonne CO 2 equivalents of greenhouse gases annually. Wood biomass combustion generates more particulate matters than natural gas combustion. However, an advanced emission control system could significantly reduce particulate matters emission from wood biomass combustion which would bring the particulate emission to a relatively similar level as for natural gas

46 CFR 97.30-1 - Repairs to boilers and pressure vessels.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Repairs to boilers and pressure vessels. 97.30-1 Section... VESSELS OPERATIONS Reports of Accidents, Repairs, and Unsafe Equipment § 97.30-1 Repairs to boilers and pressure vessels. (a) Before making any repairs to boilers or unfired pressure vessels, the chief engineer...

46 CFR 196.30-1 - Repairs to boilers and pressure vessels.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Repairs to boilers and pressure vessels. 196.30-1... VESSELS OPERATIONS Reports of Accidents, Repairs, and Unsafe Equipment § 196.30-1 Repairs to boilers and pressure vessels. (a) Before making any repairs to boilers or unfired pressure vessels, the Chief Engineer...

46 CFR 78.33-1 - Repairs of boiler and pressure vessels.

Science.gov (United States)

2010-10-01

... 46 Shipping 3 2010-10-01 2010-10-01 false Repairs of boiler and pressure vessels. 78.33-1 Section... OPERATIONS Reports of Accidents, Repairs, and Unsafe Equipment § 78.33-1 Repairs of boiler and pressure vessels. (a) Before making any repairs to boilers or unfired pressure vessels, the chief engineer shall...

Measurement of O2 in the Combustion Chamber of Apulverized Coal Boiler

Directory of Open Access Journals (Sweden)

Břetislav Janeba

2012-01-01

Full Text Available Operational measurements of the O2 concentration in the combustion chamber of a pulverized coal boiler are not yet common practice. Operators are generally satisfied with measuring the O2 concentration in the second pass of the boiler, usually behind the economizer, where a flue gas sample is extracted for analysis in a classical analyzer. A disadvantage of this approach is that there is a very weak relation between the measured value and the condition in specific locations in the fireplace, e.g. the function of the individual burners and the combustion process as a whole. A new extractionline was developed for measuring the O2 concentration in the combustion chamber. A planar lambda probe is used in this approach. The extraction line is designed to get outputs that can be used directly for diagnosis or management of the combustion in the boiler.

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)

PAH emissions from old and new types of domestic hot water boilers.

Science.gov (United States)

Horak, Jiri; Kubonova, Lenka; Krpec, Kamil; Hopan, Frantisek; Kubesa, Petr; Motyka, Oldrich; Laciok, Vendula; Dej, Milan; Ochodek, Tadeas; Placha, Daniela

2017-06-01

Five different domestic heating boilers (automatic, over-fire, with down-draft combustion and gasification) and three types of fuel (lignite, wood and mixed fuel) were examined in 25 combustion tests and correlated with the emissions of particulate matter (PM), carbon monoxide (CO), total organic carbon (TOC) and 12 polycyclic aromatic hydrocarbons (PAHs with MW = 178-278 g/mol) focusing on particle phase. However, the distribution of 12 PAHs in gas phase was considered as well due to the presence mainly of lighter PAHs in gas phase. The PAHs, as well as the CO and TOC, are the indicators of incomplete combustion, and in this study PAH emission increased significantly with increasing emissions of CO and TOC. The PAHs were mainly detected on PM 2.5 , their contents were increasing linearly with increasing PM 2.5 emissions. The highest emission factors of PAHs were measured for boilers of old construction, such as over-fire boiler (5.8-929 mg/kg) and boiler with down-draft combustion (3.1-54.1 mg/kg). Modern types of boilers produced much lower emissions of PAHs, in particular, automatic boiler (0.3-3.3 mg/kg) and gasification boilers (0.2-6.7 mg/kg). In general, the inefficient combustion at reduced output of boilers generated 1.4-17.7 times more emissions of PAHs than the combustion at nominal output of boilers. It is recommended to operate boilers at nominal output with sufficient air supply and to use the proper fuel to minimise PAHs emissions from domestic heating appliances. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

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 ...

Questions about the reliability of recovery boilers of steel smelting units

Energy Technology Data Exchange (ETDEWEB)

Sazykin, Yu K; Mukhametzyanov, N K

1979-01-01

Because the main reason for failure of recovery boilers is contamination of the heating surfaces, the operational conditions of individual elements of boiler units, equipped with vibrational and pulsed cleaning are analyzed and the reliability of the cleaning systems in use today is evaluated. The recovery boilers from open hearth furnaces and two bath steel smelting units from the Magnitogorsk Metallurgic Combine were selected as the subjects of the study. It is established that the boiler heating surface cleaning system has a quite large number of failures. The vibrational cleaning readiness factor is rated at 0.9323 and that of the pulsed cleaning system, 0.9698. For the KU-100 recovery boilers with a mean productivity of 18-20 t/h, the losses caused by failures during operation with vibration and pulsed cleaning were 3,200 and 1,700 rubles per year, respectively. With reconstruction of the boilers, which is associated with an increase in their reliability, the vibration cleaning of the heating surface was replaced by pulsed cleaning.

A review on biomass as a fuel for boilers

Energy Technology Data Exchange (ETDEWEB)

Saidur, R.; Abelaziz, E.A.; Demirbas, A.; Hossain, M.S.; Mekhilef, S. [University of Malaya, Kuala Lumpur (Malaysia). Dept. of Mechanical Engineering

2011-06-15

Currently, fossil fuels such as oil, coal and natural gas represent the prime energy sources in the world. However, it is anticipated that these sources of energy will deplete within the next 40-50 years. Moreover, the expected environmental damages such as the global warming, acid rain and urban smog due to the production of emissions from these sources have tempted the world to try to reduce carbon emissions by 80% and shift towards utilizing a variety of renewable energy resources (RES) which are less environmentally harmful such as solar, wind, biomass etc. in a sustainable way. Biomass is one of the earliest sources of energy with very specific properties. In this review, several aspects which are associated with burning biomass in boilers have been investigated such as composition of biomass, estimating the higher heating value of biomass, comparison between biomass and other fuels, combustion of biomass, co-firing of biomass and coal, impacts of biomass, economic and social analysis of biomass, transportation of biomass, densification of biomass, problems of biomass and future of biomass. It has been found that utilizing biomass in boilers offers many economical, social and environmental benefits such as financial net saving, conservation of fossil fuel resources, job opportunities creation and CO{sub 2} and NO emissions reduction. However, care should be taken to other environmental impacts of biomass such as land and water resources, soil erosion, loss of biodiversity and deforestation. Fouling, marketing, low heating value, storage and collections and handling are all associated problems when burning biomass in boilers. The future of biomass in boilers depends upon the development of the markets for fossil fuels and on policy decisions regarding the biomass market.

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.

Pencegahan Korosi Dengan Boiler Water Treatment (Bwt) Pada Ketel Uap Kapal.

OpenAIRE

Suleman, Suleman

2007-01-01

This paper explained about a using of Boiler Water Treatment (BWT) as corrosion protection for boiler on ship. BWT used as addition on boiler water, which used destilat water. As experiment results, BWT used on destilat water and destilat - seawater mixed given not koagulan patch on. The simulation given not satisfied results, caused by good not equipment.

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)

Investigation of fuel lean reburning process in a 1.5 MW boiler

International Nuclear Information System (INIS)

Kim, Hak Young; Baek, Seung Wook; Kim, Se Won

2012-01-01

Highlights: → We examine a detailed study of fuel lean reburning process in a 1.5 MW gas-fired boiler. → Experimental and numerical researches are conducted. → We investigate change in the level of NO X and CO emission. → The recirculation flow is important in the fuel lean reburning process. -- Abstract: This paper examines a detailed study of fuel lean reburning process applied to a 1.5 MW gas-fired boiler. Experimental and numerical studies were carried out to investigate the effect of the fuel lean reburning process on the NO X reduction and CO emission. Natural gas (CH 4 ) was used as the reburn as well as the main fuel. The amount of the reburn fuel, injection location and thermal load of boiler were considered as experimental parameters. The flue gas data revealed that the fuel lean reburning process led to NO X reduction up to 43%, while CO emission was limited to less than 30 ppm for the 100% thermal load condition. The commercial computational fluid dynamics code FLUENT 6.3, which included turbulence, chemical reaction, radiation and NO modeling, was used to predict the fluid flow and heat transfer characteristics under various operational conditions in the boiler. Subsequently, predicted results were validated with available measured data such as gas temperature distributions and local mean NO X concentrations. The detailed numerical results showed that the recirculation flow developed inside the boiler was found to play an important role in improving the effectiveness of fuel lean reburning process.

Theoretical and practical aspects about corrosion of refractories used in steel metallurgy: part 3: characterization of commercial refractories

International Nuclear Information System (INIS)

Braganca, S.R.

2012-01-01

In this study, it was reviewed the main aspects found in the literature about refractories corrosion, evaluating the feasibility of certain tests and relating them with experimental results. The physical properties and microstructure of commercial refractories were analyzed, considering the differences between them and the quality implications and probable life of the refractory. Thus, it was studied the various types of refractories used as lining on steel ladle. Magnesia-carbon and doloma-carbon refractories were analyzed, highlighting the differences between them. The examined refractory showed characteristics favoring high resistance to corrosion process, presenting a series of properties to be selected in accordance with industry practice. (author)

Perspectives on environmental protection of refractory metals

International Nuclear Information System (INIS)

Perking, R.A.

1992-01-01

Alloys of refractory metals which combine high strength to weight ratios with useful low-temperature toughness and ductility have been designed to meet the requirements for the next generation of high-temperature aerospace structural materials with one exception: long term resistance to oxidation. It is considered unlikely that refractory metal alloys can be modified to possess useful resistance to oxidation as bulk materials or that coating can be designed to provide high reliability fail-safe protection for the structural alloys developed to date. Recent developments indicate that bulk alloys of W and Mo can be designed to possess short term resistance to oxidation, providing a base material which can be coated to extend useful life with fail-safe protection in the event of random coating failures. Current research on silicide coatings indicates that significant improvements in coating reliability and performance also are feasible. The technical basis for these conclusions is presented in this paper and the direction of future work that could lead to environmentally stable refractory metal alloy/coating systems is discussed

Research and development of methods and technologies for CO2 capture in fossil fuel power plants and storage in geological formations in the Czech Republic. Stage 5.4: Boiler with oxyfuel technology. Revision 0

International Nuclear Information System (INIS)

Dlouhy, Tomas

2011-12-01

This phase comprised a preliminary study of boiler design modification for the oxyfuel technology. The design was developed specifically for the Prunerov II power plant. It was defined as a reference boiler for combustion using air which was consequently modified for combustion with oxygen. Changes in the construction of boiler were designed and quantified using thermal conversion, which provided the necessary modification of the sizes of the fireplace and heating surfaces. An existing general mathematical model, modified for this specific task, was used for the thermal conversion calculations

Temporal trends and spatial variation characteristics of primary air pollutants emissions from coal-fired industrial boilers in Beijing, China

International Nuclear Information System (INIS)

Xue, Yifeng; Tian, Hezhong; Yan, Jing; Zhou, Zhen; Wang, Junling; Nie, Lei; Pan, Tao; Zhou, Junrui; Hua, Shenbing; Wang, Yong; Wu, Xiaoqing

2016-01-01

Coal-fired combustion is recognized as a significant anthropogenic source of atmospheric compounds in Beijing, causing heavy air pollution events and associated deterioration in visibility. Obtaining an accurate understanding of the temporal trends and spatial variation characteristics of emissions from coal-fired industrial combustion is essential for predicting air quality changes and evaluating the effectiveness of current control measures. In this study, an integrated emission inventory of primary air pollutants emitted from coal-fired industrial boilers in Beijing is developed for the period of 2007–2013 using a technology-based approach. Future emission trends are projected through 2030 based on current energy-related and emission control policies. Our analysis shows that there is a general downward trend in primary air pollutants emissions because of the implementation of stricter local emission standards and the promotion by the Beijing municipal government of converting from coal-fired industrial boilers to gas-fired boilers. However, the ratio of coal consumed by industrial boilers to total coal consumption has been increasing, raising concerns about the further improvement of air quality in Beijing. Our estimates indicate that the total emissions of PM 10 , PM 2.5 , SO 2 , NO x , CO and VOCs from coal-fired industrial boilers in Beijing in 2013 are approximately 19,242 t, 13,345 t, 26,615 t, 22,965 t, 63,779 t and 1406 t, respectively. Under the current environmental policies and relevant energy savings and emission control plans, it may be possible to reduce NO x and other air pollutant emissions by 94% and 90% by 2030, respectively, if advanced flue gas purification technologies are implemented and coal is replaced with natural gas in the majority of existing boilers. - Highlights: • A unit-based emission inventory of coal-fired industrial boilers is developed. • Temporal trend of historical period 2007–2013 and the future till 2030 is

Applicability of newly developed 610MPa class heavy thickness high strength steel to boiler pressure vessel

Energy Technology Data Exchange (ETDEWEB)

Katayama, Norihiko; Kaihara, Shoichiro; Ishii, Jun [Ishikawajima-Harima Heavy Industries Corp., Yokohama (Japan); Kajigaya, Ichiro [Ishikawajima-Harima Heavy Industries Corp., Tokyo (Japan); Totsuka, Takehiro; Miyazaki, Takashi [Ishikawajima-Harima Heavy Industries Corp., Aioi (Japan)

1995-11-01

Construction of a 350 MW Class PFBC (Pressurized Fluidized Bed Combustion) boiler plant is under planning in Japan. Design temperature and pressure of the vessel are maximum 350 C and 1.69 MPa, respectively. As the plate thickness of the vessel exceeds over 100 mm, high strength steel plate of good weldability and less susceptible to reheat cracking was required and developed. The steel was aimed to satisfy the tensile strength over 610 MPa at 350 C after postweld heat treatment (PWHT), with good notch toughness. The authors investigated the welding performances of the newly developed steel by using 150 mm-thick plate welded by pulsed-MAG and SAW methods. It was confirmed that the newly developed steel and its welds possess sufficient strength and toughness after PWHT, and applicable to the actual pressure vessel.

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...

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...

Agglomeration of bed material: Influence on efficiency of biofuel fluidized bed boiler

Directory of Open Access Journals (Sweden)

Ryabov Georgy A.

2003-01-01

Full Text Available The successful design and operation of a fluidized bed combustor requires the ability to control and mitigate ash-related problems. The main ash-related problem of biomass filing boiler is agglomeration. The fluidized bed boiler with steam capacity of 66 t/h (4 MPa, 440 °C was started up at the Arkhangelsk Paper-Pi dp-Plant in 2001. This boiler was manufactured by the Russian companies "Energosofin" and "Belenergomash" and installed instead of the existing boiler with mechanical grate. Some constructional elements and steam drum of existing boiler remained unchanged. The primary air fan was installed past the common air fan, which supply part of the air into 24 secondary airports. First operating period shows that the bed material is expanded and then operator should increase the primary air rate, and the boiler efficiency dramatically decreases. Tills paper presents some results of our investigations of fuel, bed and fly ash chemical compositions and other characteristics. Special experiments were carried out to optimize the bed drain flow rate. The influence of secondly air supply improvement on mixing with the main flow and boiler efficiency are given.

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.

Advanced modelling and testing of a 13 MWth waste wood-fired grate boiler with recycled flue gas

DEFF Research Database (Denmark)

Rajh, Boštjan; Yin, Chungen; Samec, Niko

2016-01-01

as an innovative attempt to improve the boiler performance, a refined weighted-sum-of-grey-gases-model of greater accuracy is developed to better address the impacts of the elevated CO2 and H2O vapour concentrations on radiative heat transfer in the boiler. The impacts of full buoyancy on the turbulent flow...

EFFICIENCY OF MULTI-MODULE SOLAR COLLECTORS AS A PREFIX TO A BOILER

Directory of Open Access Journals (Sweden)

Denysova A.E.

2014-12-01

Full Text Available Influencing factors on thermal and economic efficiency of the combined of heat supply installation are established. Constructive circuits of solar heat supply "prefix" interaction with boiler installation are worked out. Mathematical models of heat exchange processes in elements of combined heat supply system with the account solar engineering characteristics are developed. The techniques of analysis of efficiency of multi-modular system of solar collectors with compulsory circulation for water heating boiler allowing calculating of efficiency factor; heat removal factor and heat transfer factor with the account of construction and operation conditions of alternative heat supply system are presented.

Ash formation, deposition, corrosion, and erosion in conventional boilers

Energy Technology Data Exchange (ETDEWEB)

Benson, S.A.; Jones, M.L. [Univ. of North Dakota, Grand Forks, ND (United States)

1995-12-01

The inorganic components (ash-forming species) associated with coals significantly affect boiler design, efficiency of operation, and lifetimes of boiler parts. During combustion in conventional pulverized fuel boilers, the inorganic components are transformed into inorganic gases, liquids, and solids. This partitioning depends upon the association of the inorganic components in the coal and combustion conditions. The inorganic components are associated as mineral grains and as organically associated elements, and these associations of inorganic components in the fuel directly influence their fate upon combustion. Combustion conditions, such as temperature and atmosphere, influence the volatility and the interaction of inorganic components during combustion and gas cooling, which influences the state and size composition distribution of the particulate and condensed ash species. The intermediate species are transported with the bulk gas flow through the combustion systems, during which time the gases and entrained ash are cooled. Deposition, corrosion, and erosion occur when the ash intermediate species are transported to the heat-transfer surface, react with the surface, accumulate, sinter, and develop strength. Research over the past decade has significantly advanced understanding of ash formation, deposition, corrosion, and erosion mechanisms. Many of the advances in understanding and predicting ash-related issues can be attributed to advanced analytical methods to determine the inorganic composition of fuels and the resulting ash materials. These new analytical techniques have been the key to elucidation of the mechanisms of ash formation and deposition. This information has been used to develop algorithms and computer models to predict the effects of ash on combustion system performance.

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.

RESULTS OF OUTPATIENT PROGRAM ON EFFECTIVE THERAPY OF REFRACTORY ARTERIAL HYPERTENSION

Directory of Open Access Journals (Sweden)

M. M. Batyushin

2015-12-01

Full Text Available Aim. To increase in efficacy of antihypertensive therapy in patients with refractory arterial hypertension (HT.Material and methods. Patients with refractory HT were revealed during first month of program. The causes of refractory HT were analyzed. Combined antihypertensive therapy was prescribed to reach target level of blood pressure (BP. This therapy lasted 24 weeks and included angiotensin converting enzyme (ACE inhibitor, thiazid diuretic (indapamide and dihydropyridine calcium antagonist (nifedipine XL.Results. 200 patients with refractory HT were revealed. True refractory HT took place in 59,9% of patients and pseudo refractory HT – in 40,1% of patients. Lack of diuretics or combined antihypertensive therapy were the main reason of insufficient BP control. Proposed 3-drugs therapy resulted in reduction of systolic BP from 190 to 132 Hg mm and diastolic BP from 104 to 81 Hg mm. Target level of BP was reached in 94% patients. There were no side effects which demanded to stop therapy.Conclusion. High incidence of pseudorefractory HT (40,1% is revealed. Significant prevalence of renal disturbances especially chronic interstitial inflammatory could be responsible for refractory HT development. Use of 3-drugs therapy (ACE inhibitor, indapamide and nifedipine XL provides effective control of BP in refractory and pseudorefractory HT.

RESULTS OF OUTPATIENT PROGRAM ON EFFECTIVE THERAPY OF REFRACTORY ARTERIAL HYPERTENSION

Directory of Open Access Journals (Sweden)

M. M. Batyushin

2007-01-01

Full Text Available Aim. To increase in efficacy of antihypertensive therapy in patients with refractory arterial hypertension (HT.Material and methods. Patients with refractory HT were revealed during first month of program. The causes of refractory HT were analyzed. Combined antihypertensive therapy was prescribed to reach target level of blood pressure (BP. This therapy lasted 24 weeks and included angiotensin converting enzyme (ACE inhibitor, thiazid diuretic (indapamide and dihydropyridine calcium antagonist (nifedipine XL.Results. 200 patients with refractory HT were revealed. True refractory HT took place in 59,9% of patients and pseudo refractory HT – in 40,1% of patients. Lack of diuretics or combined antihypertensive therapy were the main reason of insufficient BP control. Proposed 3-drugs therapy resulted in reduction of systolic BP from 190 to 132 Hg mm and diastolic BP from 104 to 81 Hg mm. Target level of BP was reached in 94% patients. There were no side effects which demanded to stop therapy.Conclusion. High incidence of pseudorefractory HT (40,1% is revealed. Significant prevalence of renal disturbances especially chronic interstitial inflammatory could be responsible for refractory HT development. Use of 3-drugs therapy (ACE inhibitor, indapamide and nifedipine XL provides effective control of BP in refractory and pseudorefractory HT.

The development of a neutralizing amines based reagent for maintaining the water chemistry for medium and high pressures steam boilers

Science.gov (United States)

Butakova, M. V.; Orlov, K. A.; Guseva, O. V.

2017-11-01

An overview of the development for neutralizing amine based reagent for water chemistry of steam boilers for medium and high pressures was given. Total values of the neutralization constants and the distribution coefficients of the compositions selected as a main criteria for reagent composition. Experimental results of using this new reagent for water chemistry in HRSG of power plant in oil-production company are discussed.

Engineering development of advanced coal-fired low-emission boiler systems. Technical progress report No. 15, April 15 1996--June 1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-08-19

The Pittsburgh Energy Technology center of the US Department of Energy (DOE) has contracted with Combustion Engineering; Inc. (ABB CE) to perform work on the {open_quotes}Engineering Development of Advanced Coal-Fired Low-Emission Boiler Systems{close_quote} Project and has authorized ABB CE to complete Phase I on a cost-reimbursable basis and Phases II and III on a cost-share basis.

Research into properties of dust from domestic central heating boiler fired with coal and solid biofuels

Directory of Open Access Journals (Sweden)

Konieczyński Jan

2017-06-01

Full Text Available The aim of this research was to assess the content and composition of the pollutants emitted by domestic central heating boilers equipped with an automatic underfeed fuel delivery system for the combustion chamber. The comparative research was conducted. It concerned fuel properties, flue gas parameters, contents of dust (fl y ash and gaseous substances polluting the air in the flue gases emitted from a domestic CH boiler burning bituminous coal, pellets from coniferous wood, cereal straw, miscanthus, and sunflower husks, coniferous tree bark, and oats and barley grain. The emission factors for dust and gaseous air pollutants were established as they are helpful to assess the contribution of such boilers in the atmospheric air pollution. When assessing the researched boiler, it was found out that despite the development in design and construction, flue gases contained fly ash with a significant EC content, which affected the air quality.

Study of flue-gas temperature difference in supercritical once-through boiler

Science.gov (United States)

Kang, Yanchang; Li, Bing; Song, Ang

2018-02-01

The 600 MW coal-fired once-through Boilers with opposed firing at a power plant are found to experience marked temperature variation and even overtemperature on the wall of the heating surface as a result of flue-gas temperature (FGT) variation in the boiler. In this study, operational adjustments were made to the pulverizing, combustion, and secondary air box systems in these boilers, in order to solve problems in internal combustion. The adjustments were found to reduce FGT difference and optimize the boiler’ combustion conditions. The results of this study can provide a reference for optimization of coal-fired boiler of the same type in similar conditions.

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.

Central Diabetes Insipidus in Refractory Antineutrophil Cytoplasmic Antibody-associated Vasculitis.

Science.gov (United States)

Ohashi, Keiji; Morishita, Michiko; Watanabe, Haruki; Sada, Ken-Ei; Katsuyama, Takayuki; Miyawaki, Yoshia; Katsuyama, Eri; Narazaki, Mariko; Tatebe, Noriko; Watanabe, Katsue; Kawabata, Tomoko; Wada, Jun

2017-11-01

We herein describe two cases of refractory antineutrophil cytoplasmic antibody-associated vasculitis (AAV) complicated with diabetes insipidus (DI) possibly related to hypertrophic pachymeningitis (HP). One patient had microscopic polyangiitis and HP, which were refractory to cyclophosphamide, azathioprine, rituximab, mycophenolate mofetil (MMF), and mizoribine. Remission was finally achieved with the use of etanercept, but DI occurred 5 years later. The other patient had granulomatosis with polyangiitis, which that was refractory to cyclophosphamide, methotrexate, MMF, and rituximab. DI subsequently developed, but was successfully treated with etanercept. Dura mater hypertrophy was macroscopically observed in the latter case.

Assessing the impact of primary measures for NOx reduction on the thermal power plant steam boiler

International Nuclear Information System (INIS)

Stupar, Goran; Tucaković, Dragan; Živanović, Titoslav; Belošević, Srdjan

2015-01-01

The European normatives prescribe content of 200 mg/Nm 3 NO x for pulverized coal combusting power plants. In order to reduce content of NO x in Serbian thermal power plant (TPP) 'Kostolac B' it's necessary to implement particular measures until 2016. The mathematical model of lignite combustion in the steam boiler furnace is defined and applied to analyze the possibility of implementing certain primary measures for reducing nitrogen oxides and their effects on the steam boiler operation. This model includes processes in the coal-fired furnace and defines radiating reactive two-phase turbulent flow. The model of turbulent flow also contains sub-model of fuel and thermal NO x formation and destruction. This complex mathematical model is related to thermal and aerodynamic calculations of the steam boiler within a unified calculation system in order to analyze the steam boiler overall work. This system provides calculations with a number of influential parameters. The steam boiler calculations for unit 1 (350 MWe) of TPP 'Kostolac B' are implemented for existing and modified combustion system in order to achieve effective, reliable and ecological facility work. The paper presents the influence analysis of large number of parameters on the steam boiler operation with an accepted concept of primary measures. Presented system of calculations is verified against measurements in TPP 'Kostolac B'. - Highlights: • Modern steam boilers need to operate according to ecological standards. • Possibility of applying some of the primary measures of NO x reduction. • Conventional calculations have no possibility to estimate sub-stoichiometric combustion. • Develop a new method of connecting the calculations. • Analysis shows the most favorable operation boiler regime (efficiency and ecology)

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...

Analytical evaluation of energy efficiency potential enhancement of heat-generating units by flow variation in the boiler circuit

Directory of Open Access Journals (Sweden)

Artamonov Pavel A.

2017-01-01

Full Text Available Three-dimensional models of the most common boiler schemes are developed and the hydraulic characteristic of each scheme is built. The calculation results of the main technical and economic indicators of the schemes are done. They are energy, metal consumption, capital costs and operating costs. According to the results of the analysis, there is a technical solution to reduce the energy consumption of the boiler circuit pumping equipment. The complex evaluation of the options in the context of the boiler manufacturer and operation is made, the investment attractiveness is calculated.

46 CFR 109.421 - Report of repairs to boilers and pressure vessels.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Report of repairs to boilers and pressure vessels. 109... Report of repairs to boilers and pressure vessels. Before making repairs, except normal repairs and maintenance such as replacement of valves or pressure seals, to boilers or unfired pressure vessels in...

Refractory versus resistant hypertension: Novel distinctive phenotypes

Science.gov (United States)

Dudenbostel, Tanja; Siddiqui, Mohammed; Gharpure, Nitin; Calhoun, David A.

2017-01-01

Resistant hypertension (RHTN) is relatively common with an estimated prevalence of 10-20% of treated hypertensive patients. It is defined as blood pressure (BP) >140/90 mmHg treated with ≥3 antihypertensive medications, including a diuretic, if tolerated. Refractory hypertension is a novel phenotype of severe antihypertensive treatment failure. The proposed definition for refractory hypertension, i.e. BP >140/90 mmHg with use of ≥5 different antihypertensive medications, including a diuretic and a mineralocorticoid receptor antagonist (MRA) has been applied inconsistently. In comparison to RHTN, refractory hypertension seems to be less prevalent than RHTN. This review focuses on current knowledge about this novel phenotype compared with RHTN including definition, prevalence, mechanisms, characteristics and comorbidities, including cardiovascular risk. In patients with RHTN excess fluid retention is thought to be a common mechanism for the development of RHTN. Recently, evidence has emerged suggesting that refractory hypertension may be more of neurogenic etiology due to increased sympathetic activity as opposed to excess fluid retention. Treatment recommendations for RHTN are generally based on use and intensification of diuretic therapy, especially with the combination of a long-acting thiazide-like diuretic and an MRA. Based on findings from available studies, such an approach does not seem to be a successful strategy to control BP in patients with refractory hypertension and effective sympathetic inhibition in such patients, either with medications and/or device based approaches may be needed. PMID:29034321

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...

A bottom-up method to develop pollution abatement cost curves for coal-fired utility boilers

Science.gov (United States)

This paper illustrates a new method to create supply curves for pollution abatement using boiler-level data that explicitly accounts for technology costs and performance. The Coal Utility Environmental Cost (CUECost) model is used to estimate retrofit costs for five different NO...

Hardware and software techniques for boiler operation and management

Energy Technology Data Exchange (ETDEWEB)

Kobayashi, Hiroshi (Hirakawa Iron Works, Ltd., Osaka (Japan))

1989-04-01

A study was conducted on the requirements for easy-operable boiler from the view points of hardware and software technologies. Relation among efficiency, energy-saving, and economics, and control of total emission regarding low NOx operation, were explained, with suggestion of orientation to developed necessary hard- and soft- ware for the realization. 8 figs.

Emission analysis of the best available wood-fired central heating boilers on the market

International Nuclear Information System (INIS)

Axell, M.; Gustavsson, Lennart; Persson, Henrik; Leckner, B.

1998-01-01

The purpose of the present project is to study the emissions from some of the best available wood-fired central heating boilers on the market. The aim is to identify the critical factors which determine the emission levels by means of emission measurements as well as temperature measurements in the combustion chamber. Four boilers with different design characteristics have been included in the project. All boilers use reversed combustion and fan-assisted combustion air supply, and have shown low tar emissions in earlier environmental tests. Boiler A is a boiler with a rather large mass of ceramics in the grate and in the burn-out zone, and a large volume of water. Boiler B has a smaller mass in the cast-iron grate and in the burn-out zone and a small water volume. Boiler C is a boiler with tertiary air and an incorporated accumulator tank. Boiler D has a zirconia-cell probe for continuous control of the air-excess ratio. The measurements have been made with the boilers in accumulator operation, i.e. at maximum heat output, since they are intended for this type of operation. Tests have, in addition to normal operating conditions, been made with high fuel moisture contents, high draught and a low boiler temperature at the start of the test. Measurements have been made of excess-air ratios, contents of CO, total hydrocarbons (THC), NO x and a number of volatile organic compounds (VOC) in the flue gases as well as of combustion temperatures below the grate

1300°F 800 MWe USC CFB Boiler Design Study

Science.gov (United States)

Robertson, Archie; Goidich, Steve; Fan, Zhen

Concern about air emissions and the effect on global warming is one of the key factors for developing and implementing new advanced energy production solutions today. One state-of-the-art solution is circulating fluidized bed (CFB) combustion technology combined with a high efficiency once-through steam cycle. Due to this extremely high efficiency, the proven CFB technology offers a good solution for CO2 reduction. Its excellent fuel flexibility further reduces CO2 emissions by co-firing coal with biomass. Development work is under way to offer CFB technology up to 800MWe capacities with ultra-supercritical (USC) steam parameters. In 2009 a 460MWe once-through supercritical (OTSC) CFB boiler designed and constructed by Foster Wheeler will start up. However, scaling up the technology further to 600-800MWe with net efficiency of 45-50% is needed to meet the future requirements of utility operators. To support the move to these larger sizes, an 800MWe CFB boiler conceptual design study was conducted and is reported on herein. The use of USC conditions (˜11 00°F steam) was studied and then the changes, that would enable the unit to generate 1300°F steam, were identified. The study has shown that by using INTREX™ heat exchangers in a unique internal-external solids circulation arrangement, Foster Wheeler's CFB boiler configuration can easily accommodate 1300°F steam and will not require a major increase in heat transfer surface areas.

Fuel-oil boilers are improving; Les chaudieres a fioul progressent

Energy Technology Data Exchange (ETDEWEB)

Anon.

2000-08-01

The share of domestic fuel oil consumption in France is progressively growing up in space heating applications. In order to perennialize this growth, the 'Chauffage Fioul' association has developed an advertising strategy for the promotion of fuel-oil boilers in accommodations. Short paper. (J.S.)

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)

Firing a sub-bituminous coal in pulverized coal boilers configured for bituminous coals

Energy Technology Data Exchange (ETDEWEB)

N. Spitz; R. Saveliev; M. Perelman; E. Korytni; B. Chudnovsky; A. Talanker; E. Bar-Ziv [Ben-Gurion University of the Negev, Beer-Sheva (Israel)

2008-07-15

It is important to adapt utility boilers to sub-bituminous coals to take advantage of their environmental benefits while limiting operation risks. We discuss the performance impact that Adaro, an Indonesian sub-bituminous coal with high moisture content, has on opposite-wall and tangentially-fired utility boilers which were designed for bituminous coals. Numerical simulations were made with GLACIER, a computational-fluid-dynamic code, to depict combustion behavior. The predictions were verified with full-scale test results. For analysis of the operational parameters for firing Adaro coal in both boilers, we used EXPERT system, an on-line supervision system developed by Israel Electric Corporation. It was concluded that firing Adaro coal, compared to a typical bituminous coal, lowers NOx and SO{sub 2} emissions, lowers LOI content and improves fouling behavior but can cause load limitation which impacts flexible operation. 21 refs., 7 figs., 3 tabs.

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...

Exergy analysis of a circulating fluidized bed boiler cogeneration power plant

International Nuclear Information System (INIS)

Gürtürk, Mert; Oztop, Hakan F.

2016-01-01

Highlights: • Analysis of energy and exergy for a cogeneration power plant have been performed. • This plant has circulating fluidized bed boiler. • Energy and exergy efficiencies of the boiler are obtained as 84.65% and 29.43%, respectively. • Exergy efficiency of the plant was calculated as 20%. - Abstract: In this study, energy and exergy analysis of a cogeneration power plant have been performed. The steam which is produced by the cogeneration power plant is used for salt production and most important part of the cogeneration power plant is the circulation fluidized bed boiler. Energy and exergy efficiency of the circulation fluidized bed boiler were found as 84.65% and 29.43%, respectively. Exergy destruction of the circulation fluidized bed boiler was calculated as 21789.39 kW and 85.89% of exergy destruction in the plant. The automation system of the cogeneration power plant is insufficient. Exergy efficiency of the plant was calculated as 20%. Also, some design parameters increasing energy losses were determined.

46 CFR 50.05-5 - Existing boilers, pressure vessels or piping systems.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Existing boilers, pressure vessels or piping systems. 50... ENGINEERING GENERAL PROVISIONS Application § 50.05-5 Existing boilers, pressure vessels or piping systems. (a) Whenever doubt exists as to the safety of an existing boiler, pressure vessel, or piping system, the marine...

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.

Evaluation of the reusing of MGO-C refractory brick in refractory mixes

International Nuclear Information System (INIS)

Silva, R.D.S. da; Braganca, S.R.

2012-01-01

The residue from the use of MgO-C refractories in electric arc furnace presents, mostly, magnesium oxide in its composition and some slag contamination and impurities from the process of electrofusion scrap iron/steel. In this study, it was studied the characteristics of this residue and reused through its introduction into a commercial refractory mix, employed as material of coating and repair. This refractory mix was tested by thermogravimetric analysis, compressive strength, evaluation of plasticity and porosity as well as aspects of its installation, such as adhesion in situ. Results showed that there potential for reuse with the introduction of the waste in commercial mix was 30%, with little loss of compressive strength and plasticity. (author)

Data-driven modeling and predictive control for boiler-turbine unit using fuzzy clustering and subspace methods.

Science.gov (United States)

Wu, Xiao; Shen, Jiong; Li, Yiguo; Lee, Kwang Y

2014-05-01

This paper develops a novel data-driven fuzzy modeling strategy and predictive controller for boiler-turbine unit using fuzzy clustering and subspace identification (SID) methods. To deal with the nonlinear behavior of boiler-turbine unit, fuzzy clustering is used to provide an appropriate division of the operation region and develop the structure of the fuzzy model. Then by combining the input data with the corresponding fuzzy membership functions, the SID method is extended to extract the local state-space model parameters. Owing to the advantages of the both methods, the resulting fuzzy model can represent the boiler-turbine unit very closely, and a fuzzy model predictive controller is designed based on this model. As an alternative approach, a direct data-driven fuzzy predictive control is also developed following the same clustering and subspace methods, where intermediate subspace matrices developed during the identification procedure are utilized directly as the predictor. Simulation results show the advantages and effectiveness of the proposed approach. Copyright © 2014 ISA. Published by Elsevier Ltd. All rights reserved.

Lagisza, world's largest CFB boiler, begins commercial operation

Energy Technology Data Exchange (ETDEWEB)

Nuortimo, K. [Foster Wheeler, Varkaus (Finland)

2010-04-15

Early operating experience with the Lagisza circulating fluidised bed (CFB) boiler in Poland - the world's largest such boiler to date, and also the first one with supercritical steam conditions - has been positive. 3 figs., 4 tabs.

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.

Application of Coal Thermal Treatment Technology for Oil-Free Firing of Boilers

Science.gov (United States)

Aliyarov, B.; Mergalimova, A.; Zhalmagambetova, U.

2018-04-01

The theoretical and practical introduction of this kind of firing boiler units in coal thermal power plants is considered in the article. The results of an experimental study of three types of coals are presented in order to obtain the required gaseous fuel. The aim of the study is to develop a new, economically and ecologically more acceptable method for firing boilers at thermal power plants, which is able to exclude the use of expensive and inconvenient fuel oil. The tasks of the experiment are to develop a technological scheme of kindling of boilers at thermal power plants, using as a type of ignition fuel volatile combustible substances released during the heating of coal, and to investigate three types of coal for the suitability of obtaining gaseous fuels, in sufficient volume and with the required heat of combustion. The research methods include the analysis of technical and scientific-methodological literature on the problem of the present study, the study of the experience of scientists of other countries, the full-scale experiment on the production of volatile combustible substances. During the full-scale experiment, the coal of 3 fields of Kazakhstan has been studied: Shubarkul, Maikuben and Saryadyr. The analysis has been performed and the choice of the most convenient technology for boiler kindling and maintenance of steady burning of the torch has been made according to the proposed method, as well as the corresponding technological scheme has been developed. As a result of the experiment, it can be stated that from coal in the process of its heating (without access to oxygen), it is possible to obtain a sufficient amount of combustible volatile substances. The released gaseous fuel has the necessary parameters and is quite capable of replacing an expensive fuel oil. The resulting gaseous fuel is quite convenient to use and environmentally cleaner. The piloting scheme developed as a result of the experiment can be introduced in pulverized

NOVEL REFRACTORY MATERIALS FOR HIGH ALKALI, HIGH TEMPERATURE ENVIRONMENTS

Energy Technology Data Exchange (ETDEWEB)

Hemrick, James Gordon [ORNL; Smith, Jeffrey D [ORNL; O' Hara, Kelley [University of Missouri, Rolla; Rodrigues-Schroer, Angela [Minteq International, Inc.; Colavito, [Minteq International, Inc.

2012-08-01

A project was led by Oak Ridge National Laboratory (ORNL) in collaboration with a research team comprised of the academic institution Missouri University of Science and Technology (MS&T), and the industrial company MINTEQ International, Inc. (MINTEQ), along with representatives from the aluminum, chemical, glass, and forest products industries. The project was to address the need for new innovative refractory compositions by developing a family of novel MgO-Al 2O3, MgAl2O4, or other similar spinel structured or alumina-based unshaped refractory compositions (castables, gunnables, shotcretes, etc.) utilizing new aggregate materials, bond systems, protective coatings, and phase formation techniques (in-situ phase formation, altered conversion temperatures, accelerated reactions, etc). This family of refractory compositions would then be tailored for use in high-temperature, high-alkaline industrial environments like those found in the aluminum, chemical, forest products, glass, and steel industries. Both practical refractory development experience and computer modeling techniques were used to aid in the design of this new family of materials. The newly developed materials were expected to offer alternative material choices for high-temperature, high-alkali environments that were capable of operating at higher temperatures (goal of increasing operating temperature by 100-200oC depending on process) or for longer periods of time (goal of twice the life span of current materials or next process determined service increment). This would lead to less process down time, greater energy efficiency for associated manufacturing processes (more heat kept in process), and materials that could be installed/repaired in a more efficient manner. The overall project goal was a 5% improvement in energy efficiency (brought about through a 20% improvement in thermal efficiency) resulting in a savings of 3.7 TBtu/yr (7.2 billion ft3 natural gas) by the year 2030. Additionally, new

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....

Numerical investigation of heat transfer characteristics in utility boilers of oxy-coal combustion

International Nuclear Information System (INIS)

Hu, Yukun; Li, Hailong; Yan, Jinyue

2014-01-01

Highlights: • Air-coal and oxy-coal combustion in an industrial scale PF boiler were simulated in ANSYS FLUENT. • The O 2 concentration of 33 vol% in the oxy-coal combustion case matches the air-coal combustion case most closely. • The moisture in the flue gas has little impact on flame temperature, but positive impact on surface incident radiation. - Abstract: Oxy-coal combustion has different flue gas composition from the conventional air-coal combustion. The different composition further results in different properties, such as the absorption coefficient, emissivity, and density, which can directly affect the heat transfer in both radiation and convection zones of utility boilers. This paper numerically studied a utility boiler of oxy-coal combustion and compares with air-coal combustion in terms of flame profile and heat transferred through boiler side walls in order to understand the effects of different operating conditions on oxy-coal boiler retrofitting and design. Based on the results, it was found that around 33 vol% of effective O 2 concentration ([O 2 ] effective ) the highest flame temperature and total heat transferred through boiler side walls in the oxy-coal combustion case match to those in the air-coal combustion case most; therefore, the 33 vol% of [O 2 ] effective could result in the minimal change for the oxy-coal combustion retrofitting of the existing boiler. In addition, the increase of the moisture content in the flue gas has little impact on the flame temperature, but results in a higher surface incident radiation on boiler side walls. The area of heat exchangers in the boiler was also investigated regarding retrofitting. If boiler operates under a higher [O 2 ] effective , to rebalance the load of each heat exchanger in the boiler, the feed water temperature after economizer can be reduced or part of superheating surfaces can be moved into the radiation zone to replace part of the evaporators

Optimising boiler performance.