WorldWideScience

Sample records for boiler process model

  1. 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

  2. Bed models for solid fuel conversion process in grate-fired boilers

    DEFF Research Database (Denmark)

    Costa, M.; Massarotti, N.; Indrizzi, V.

    2013-01-01

    to describe the thermo-chemical conversion process of a solid fuel bed in a grate-fired boiler is presented. In this work both models consider the incoming solid fuel as subjected to drying, pyrolysis, gasification and combustion. In the first approach the biomass bed is treated as a 0D system, but the thermo......Because of the complexity to describe and solve thermo-chemical processes occurring in a fuel bed in grate-fired boiler, it is often necessary to simplify the process and use modeling techniques based on overall mass, energy and species conservation. A comparison between two numerical models......-chemical processes are divided in two successive sections: drying and conversion (which includes pyrolysis, gasification and combustion). The second model is an empirical 1D approach. The two models need input data such as composition, temperature and feeding rate of biomass and primary air. Temperature, species...

  3. Engineering bed models for solid fuel conversion process in grate-fired boilers

    DEFF Research Database (Denmark)

    Costa, M.; Massarotti, N.; Indrizzi, V.

    2014-01-01

    A comparison between two numerical models describing the thermo-chemical conversion process of a solid fuel bed in a grate-fired boiler is presented. Both models consider the incoming biomass as subjected to drying, pyrolysis, gasification and combustion. In the first approach the biomass bed...... of the syngas predicted by the two models is equal to about 7%. The application to different types of biomass shows that the difference in the predictions increases as the carbon content grows. The phenomenological model, in fact, generally considers higher conversion rates of this element to volatiles...

  4. MODELLING, SIMULATING AND OPTIMIZING BOILERS

    DEFF Research Database (Denmark)

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

    2004-01-01

    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...... size. The model has been formulated with a specied building-up of the pressure during the start-up of the plant, i.e. the steam production during start-up of the boiler is output from the model. The steam outputs together with requirements with respect to steam space load have been utilized to dene...... of the boiler is (with an acceptable accuracy) proportional with the volume of the boiler. For the dynamic operation capability a cost function penalizing limited dynamic operation capability and vise-versa has been dened. The main idea is that it by mean of the parameters in this function is possible to t its...

  5. Modified graphical autocatalytic set model of combustion process in circulating fluidized bed boiler

    Science.gov (United States)

    Yusof, Nurul Syazwani; Bakar, Sumarni Abu; Ismail, Razidah

    2014-07-01

    Circulating Fluidized Bed Boiler (CFB) is a device for generating steam by burning fossil fuels in a furnace operating under a special hydrodynamic condition. Autocatalytic Set has provided a graphical model of chemical reactions that occurred during combustion process in CFB. Eight important chemical substances known as species were represented as nodes and catalytic relationships between nodes are represented by the edges in the graph. In this paper, the model is extended and modified by considering other relevant chemical reactions that also exist during the process. Catalytic relationship among the species in the model is discussed. The result reveals that the modified model is able to gives more explanation of the relationship among the species during the process at initial time t.

  6. MODELLING, SIMULATING AND OPTIMIZING BOILERS

    DEFF Research Database (Denmark)

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

    2003-01-01

    This paper describes the modelling, simulating and optimizing including experimental verification as being carried out as part of a Ph.D. project being written resp. supervised by the authors. The work covers dynamic performance of both water-tube boilers and fire tube boilers. A detailed dynamic...... model of the boiler has been developed and simulations carried out by means of the Matlab integration routines. The model is prepared as a dynamic model consisting of both ordinary differential equations and algebraic equations, together formulated as a Differential-Algebraic-Equation system. Being able...... to operate a boiler plant dynamically means that the boiler designs must be able to absorb any fluctuations in water level and temperature gradients resulting from the pressure change in the boiler. On the one hand a large water-/steam space may be required, i.e. to build the boiler as big as possible. Due...

  7. MODELLING, SIMULATING AND OPTIMIZING BOILERS

    DEFF Research Database (Denmark)

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

    2004-01-01

    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...... size. The model has been formulated with a specied building-up of the pressure during the start-up of the plant, i.e. the steam production during start-up of the boiler is output from the model. The steam outputs together with requirements with respect to steam space load have been utilized to dene...

  8. Modelling, simulating and optimizing Boilers

    DEFF Research Database (Denmark)

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

    2003-01-01

    of the boiler has been developed and simulations carried out by means of the Matlab integration routines. The model is prepared as a dynamic model consisting of both ordinary differential equations and algebraic equations, together formulated as a Differential-Algebraic- Equation system. Being able to operate...

  9. 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.

  10. Structured Mathematical Modeling of Industrial Boiler

    OpenAIRE

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

    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...

  11. 40 CFR 65.149 - Boilers and process heaters.

    Science.gov (United States)

    2010-07-01

    ... thermal units per hour) or greater. (ii) A boiler or process heater into which the vent stream is... 40 Protection of Environment 15 2010-07-01 2010-07-01 false Boilers and process heaters. 65.149... System or a Process § 65.149 Boilers and process heaters. (a) Boiler and process heater equipment...

  12. 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.

  13. MODELLING, SIMULATING AND OPTIMIZING BOILERS

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  14. Modelling, simulating and optimizing Boilers

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  15. 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

  16. 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...

  17. 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...

  18. 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....

  19. Modelling and simulating fire tube boiler performance

    DEFF Research Database (Denmark)

    Sørensen, Kim; Karstensen, Claus; Condra, Thomas Joseph;

    2003-01-01

    A model for a ue gas boiler covering the ue 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 dened 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 MatLab/Simulink has...... been applied for carrying out the simulations. To be able to verify the simulated results an experiments has been carried out on a full scale boiler plant....

  20. A mathematical model for optimized operation and control in a CDQ-Boiler system

    Institute of Scientific and Technical Information of China (English)

    De Wang; Tao Yang; Zhi Wen; Junxiao Feng; Ning Kong; Qin Wang; Weimin Wang

    2005-01-01

    Based on analyzing the thermal process of a CDQ (coke dry quenching)-Boiler system, the mathematical model for optimized operation and control in the CDQ-Boiler system was developed. It includes a mathematical model for heat transferring process in the CDQ unit, a mathematical model for heat transferring process in the boiler and a combustion model for circulating gas in the CDQ-Boiler system. The model was verified by field data, then a series of simulations under several typical operating conditions of CDQ-Boiler were carried on, and in tum, the online relation formulas between the productivity and the optimal circulating gas, and the one between the productivity and the optimal second air, were achieved respectively. These relation equations have been successfully used in a CDQ-Boiler computer control system in the Baosteel, to realize online optimized guide and control, and meanwhile high efficiency in the CDQ-Boiler system has been achieved.

  1. 40 CFR 63.988 - Incinerators, boilers, and process heaters.

    Science.gov (United States)

    2010-07-01

    ... bed. (3) Where a boiler or process heater of less than 44 megawatts (150 million British thermal units... heaters. 63.988 Section 63.988 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Routing to a Fuel Gas System or a Process § 63.988 Incinerators, boilers, and process heaters....

  2. 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.)

  3. Efficiency of Small Scale Manually Fed Boilers —Mathematical Models

    Directory of Open Access Journals (Sweden)

    Lazar Savin

    2012-05-01

    Full Text Available This study reviews test results for a biomass-fired hot water boiler with a nominal boiler thermal power of 120 kW. In the experiments, prismatic wheat straw bales were used as biomass. The impact of the quantity (220, 290, 360 and 430 m3 h−1 of inlet air fed to the boiler firebox was continuously monitored. This was to examine the influence of the quantity of inlet air and recirculation (0, 16.5 and 33% of combustion products on the boiler thermal power and boiler energy efficiency. Thus, the following mathematical models and formulas were presented: correlation between boiler thermal power and bale residence time; bale mass loss during the combustion process; correlation between boiler energy efficiency and bale residence time. Mathematical models were obtained by using experimental data and by applying nonlinear regression analysis. Adjustment evaluation of mathematical models with experimental data was performed based on the determination coefficient, t-test and F-test. Increase the amount of air throughout the firebox produced boiler thermal power increase and bale residence time decrease. It was shown that combustion products recirculation of 16.5% partly improved boiler characteristics, while the recirculation of 33% did not, comparing with the case without recirculation.

  4. 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.

  5. Numerical methods application to study processes in the CFB boilers combustion chambers

    Directory of Open Access Journals (Sweden)

    Koksharev Oleg M.

    2017-01-01

    Full Text Available This paper presents the application of numerical calculation of a hybrid Euler–Lagrange approach to model the gas–solid flow combined with a combustion process in the CFB boiler that has been resolved by applying the ANSYS FLUENT 14.0. In this work, the numerical modelling of furnace processes at various speeds of airflow supply from below was estimated. For the design speed adopted values of 0.5, 1.5, 2.5 and 5 m/s. The research object is the combustion chamber of boiler unit with CFB, with steam capacity of 230 t/h.

  6. Numerical methods application to study processes in the CFB boilers combustion chambers

    OpenAIRE

    Koksharev Oleg M.; Gil Andrey V.

    2017-01-01

    This paper presents the application of numerical calculation of a hybrid Euler–Lagrange approach to model the gas–solid flow combined with a combustion process in the CFB boiler that has been resolved by applying the ANSYS FLUENT 14.0. In this work, the numerical modelling of furnace processes at various speeds of airflow supply from below was estimated. For the design speed adopted values of 0.5, 1.5, 2.5 and 5 m/s. The research object is the combustion chamber of boiler unit with CFB, with ...

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

    Energy Technology Data Exchange (ETDEWEB)

    David W. Gandy; John P. Shingledecker

    2011-04-11

    Forced outages and boiler unavailability in conventional coal-fired fossil power plants is most often caused by fireside corrosion of boiler waterwalls. Industry-wide, the rate of wall thickness corrosion wastage of fireside waterwalls in fossil-fired boilers has been of concern for many years. It is significant that the introduction of nitrogen oxide (NOx) emission controls with staged burners systems has increased reported waterwall wastage rates to as much as 120 mils (3 mm) per year. Moreover, the reducing environment produced by the low-NOx combustion process is the primary cause of accelerated corrosion rates of waterwall tubes made of carbon and low alloy steels. Improved coatings, such as the MCrAl nanocoatings evaluated here (where M is Fe, Ni, and Co), are needed to reduce/eliminate waterwall damage in subcritical, supercritical, and ultra-supercritical (USC) boilers. The first two tasks of this six-task project-jointly sponsored by EPRI and the U.S. Department of Energy (DE-FC26-07NT43096)-have focused on computational modeling of an advanced MCrAl nanocoating system and evaluation of two nanocrystalline (iron and nickel base) coatings, which will significantly improve the corrosion and erosion performance of tubing used in USC boilers. The computational model results showed that about 40 wt.% is required in Fe based nanocrystalline coatings for long-term durability, leading to a coating composition of Fe-25Cr-40Ni-10 wt.% Al. In addition, the long term thermal exposure test results further showed accelerated inward diffusion of Al from the nanocrystalline coatings into the substrate. In order to enhance the durability of these coatings, it is necessary to develop a diffusion barrier interlayer coating such TiN and/or AlN. The third task 'Process Advanced MCrAl Nanocoating Systems' of the six-task project jointly sponsored by the Electric Power Research Institute, EPRI and the U.S. Department of Energy (DE-FC26-07NT43096)- has focused on

  8. Modeling operation mode of pellet boilers for residential heating

    Science.gov (United States)

    Petrocelli, D.; Lezzi, A. M.

    2014-11-01

    In recent years the consumption of wood pellets as energy source for residential heating lias increased, not only as fuel for stoves, but also for small-scale residential boilers that, produce hot water used for both space heating and domestic hot water. Reduction of fuel consumption and pollutant emissions (CO, dust., HC) is an obvious target of wood pellet boiler manufacturers, however they are also quite interested in producing low- maintenance appliances. The need of frequent maintenance turns in higher operating costs and inconvenience for the user, and in lower boiler efficiency and higher emissions also. The aim of this paper is to present a theoretical model able to simulate the dynamic behavior of a pellet boiler. The model takes into account many features of real pellet boilers. Furthermore, with this model, it is possible to pay more attention to the influence of the boiler control strategy. Control strategy evaluation is based not only on pellet consumption and on total emissions, but also on critical operating conditions such as start-up and stop or prolonged operation at substantially reduced power level. Results are obtained for a residential heating system based on a wood pellet boiler coupled with a thermal energy storage. Results obtained so far show a weak dependence of performance in terms of fuel consumption and total emissions on control strategy, however some control strategies present some critical issues regarding maintenance frequency.

  9. 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

  10. Dynamic simulation model for ultra supercritical 1 000 MW unit boilers%Dynamic simulation model for ultra supercritical 1000 MW unit boilers

    Institute of Scientific and Technical Information of China (English)

    XU Hui; XU Ershu

    2013-01-01

    On the basis of heat transfer characteristics of working fluid at different pressures inside the water wall tube and structure of the ultra supercritical 1 000 MW unit once through boiler in Jianbi Power Plant,the varying phase transformation point method was adopted to establish the moving-boundary dynamic simulation model of water wall in ultra supercritical once through boilers,especially the length variation of hot water section,evaporation section and superheat section against the load changing.On this basis,the real-time dynamic simulation model for ultra-supercritical 1 000 MW unit boiler in Jianbi Power Plant was built on the STAR-90 simulation platform.The dynamic and static characteristics test showed that,this model can simulate the unit's startup/shutdown process and some typical fault conditions accurately,and had good dynamic and static performance.

  11. 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...... and the existing control system has been developed and validated. The optimizing control system has been developed and tested by extensive use of the simulation model. Simulation results indicate that a reduction of steam temperature deviations of about 75% can be obtained. The advantages of using a simulation...... model when designing a new control concept are discussed....

  12. Modelling of a one pass smoke tube boiler

    DEFF Research Database (Denmark)

    Karstensen, Claus M. S.; Sørensen, Kim

    2004-01-01

    A nonlinear state-space model with five states describing a one pass smoke tube boiler has been formulated. By means of mass- and energy-balance the model describes the dynamics of the Furnace, the Convection Zone and the Water/Steam Part and the three sub models are merged into an overall model...

  13. Modelling of a one pass smoke tube boiler

    DEFF Research Database (Denmark)

    Karstensen, Claus M. S.; Sørensen, Kim

    2004-01-01

    A nonlinear state-space model with five states describing a one pass smoke tube boiler has been formulated. By means of mass- and energy-balance the model describes the dynamics of the Furnace, the Convection Zone and the Water/Steam Part and the three sub models are merged into an overall model...

  14. Modelling and Simulation of the 50 MWe CFBC Boiler

    Institute of Scientific and Technical Information of China (English)

    WeidouNi; ZhengLi

    1994-01-01

    A general mathematical model of CFBC boiler by taking the 50 MWe Tsinghua CFBC boiler as the object is established.the model has some distinguished features,Firstly,in order to describe the CFBC precisely,emphasis is paid to take the broad soze distribution of feeding coal and bed invertory into consideration.Secondly,the emplogying of cell model makes it possible to show the distribution of any interested vaiabled inside furnace,Thirdly,since partial aspects such as hydrodynamics,devolatilization of coal,combustion of char and the formation and reduction of harmful substances are considered in detail,therefore the emission at the outlet of the furnace can be estimated .By using the model,simulation is carried out to predict the performance of the 50 MWe Tsinghua CFBC boiler for both design and off-design operation.The results are useful for dsigners and possible improvement of design.

  15. Modelling of coal combustion enhanced through plasma-fuel systems in full-scale boilers

    Energy Technology Data Exchange (ETDEWEB)

    A.S. Askarova; Z. Jankoski; E.I. Karpenko; E.I. Lavrischeva; F.C. Lockwood; V.E. Messerle; A.B. Ustimenko [al-Farabi Kazakh National University, Almaty (Kazakhstan). Department of Physics

    2005-07-01

    Plasma activation promotes more effective and environmental friendly low-rank coal combustion. This work presents numerical modelling results of plasma thermochemical preparation of pulverized coal for ignition and combustion in the furnace of a utility boiler. Two kinetic mathematical models were used in the investigation of the processes of air-fuel mixture plasma activation, ignition and combustion. A 1D kinetic code, PLASMA-COAL, calculates the concentrations of species, temperatures and velocities of treated coal-air mixtures in a burner incorporating a plasma source. It gives initial data for 3D-modeling of power boilers furnaces by the code FLOREAN. A comprehensive image of plasma activated coal combustion processes in a furnace of pulverised coal fired boiler was obtained. The advantages of the plasma technology are clearly demonstrated. 15 refs., 6 figs., 4 tabs.

  16. 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

    Numerical modelling is widely used in industry for detailed understanding of the combustion process and for appropriate design and optimization of biomass/waste-fired boilers. This paper presents a numerical study of a 13 MWth waste wood-fired grate boiler, based on the coupled in-bed fuel...... conversion modelling and freeboard combustion modelling methodology. A 1D model is developed for the conversion of the waste wood in the fuel bed on the grate, providing the appropriate grate inlet condition for the 3D simulation of the freeboard region. Since part of the flue gas is recycled into the boiler...

  17. 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. Th......). In the thesis the pressure control is based on this new method when on/off burner switching is required while the water level control is handled by a model predictive controller........ 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...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-06-21

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

  19. An alternative process to treat boiler feed water for reuse.

    Science.gov (United States)

    Guirgis, Adel; Ghosh, Jyoti P; Achari, Gopal; Langford, Cooper H; Banerjee, Daliya

    2012-09-01

    A bench-scale process to treat boiler feed water for reuse in steam generation was developed. Industrial water samples from a steam-assisted gravity drainage plant in northern Alberta, Canada, were obtained and samples characterized. The technology, which consists of coagulation-settling to remove oil/grease and particulates followed by an advanced oxidative treatment, led to clean water samples with negligible organic carbon. Coagulation followed by settling removed most particulates and some insoluble organics. The advanced oxidative treatment removed any remaining color in the samples, decreased the organic content to near-zero, and provided water ready for reuse.

  20. Analysis of selected problems of biomass combustion process in batch boilers - experimental and numerical approach

    Directory of Open Access Journals (Sweden)

    Szubel Mateusz

    2016-01-01

    Full Text Available It is possible to list numerous groups of heating units that are used in households, such as boilers, stoves and units used as supporting heat sources, namely fireplaces. In each case, however, the same operational problems may be evoked [1]. To understand the causes of energy losses in a boiler system, a proper definition of significant elements of the unit’s heat balance is necessary. In the group of energy losses, the flue gas loss and the incomplete combustion loss are the most significant factors. The problem with the loss resulting from incomplete combustion, which is related to the presence of combustible substances in the exhaust, is especially significant in case of biomass boilers [2, 3]. The paper presents results of the research and the optimisation of the biomass combustion process in the 180 kW batch boiler. The studies described have been focused on the reduction of the pollutants emission, which was primarily realised by the modifications of the air feeding system. Results of the experiments and the CFD simulations have been compared and discussed. Both in case of the model as well as the experiment, positive influence of the modifications on the emission have been observed.

  1. Data Analytics Based Dual-Optimized Adaptive Model Predictive Control for the Power Plant Boiler

    Directory of Open Access Journals (Sweden)

    Zhenhao Tang

    2017-01-01

    Full Text Available To control the furnace temperature of a power plant boiler precisely, a dual-optimized adaptive model predictive control (DoAMPC method is designed based on the data analytics. In the proposed DoAMPC, an accurate predictive model is constructed adaptively by the hybrid algorithm of the least squares support vector machine and differential evolution method. Then, an optimization problem is constructed based on the predictive model and many constraint conditions. To control the boiler furnace temperature, the differential evolution method is utilized to decide the control variables by solving the optimization problem. The proposed method can adapt to the time-varying situation by updating the sample data. The experimental results based on practical data illustrate that the DoAMPC can control the boiler furnace temperature with errors of less than 1.5% which can meet the requirements of the real production process.

  2. Development and Demonstration of a Biomass Boiler for Food Processing Applications

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-02-01

    Burns & McDonnell Engineering Company, in collaboration with Frito-Lay, Inc., Oak Ridge National Laboratory, CPL Systems, Inc., Alpha Boilers, and Kansas State University will demonstrate use of a biomass boiler in the food processing industry. The 60,000 lb/hr innovative biomass boiler system utilizing a combination of wood waste and tire-derived fuel (TDF) waste will offset all natural gas consumption at Frito-Lay's Topeka, Kansas, processing facility.

  3. 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

  4. 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 limited requirements? 63.7506 Section 63.7506 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... or process heaters have limited requirements? (a) New or reconstructed boilers and process heaters...

  5. Mixing Studies in a 1:60 scale model of a cornerfired boiler with OFA

    DEFF Research Database (Denmark)

    Matlok, Simon; Scheel Larsen, Poul; Gjernes, Erik;

    1998-01-01

    In a model of a boiler, concentration distributions of injected gas into a swirling bulk flow are determined from quantitative laser-sheet visualization. Together with LDA-measurements of velocity fields this describes the mixing process and its efficiency expressed by several measures (unmixedness...

  6. 40 CFR 63.7491 - Are any boilers or process heaters not subject to this subpart?

    Science.gov (United States)

    2010-07-01

    ...., hazardous waste boilers). (e) A commercial and industrial solid waste incineration unit covered by 40 CFR... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Industrial, Commercial... process heaters not subject to this subpart? The types of boilers and process heaters listed in paragraphs...

  7. 76 FR 28662 - Industrial, Commercial, and Institutional Boilers and Process Heaters and Commercial and...

    Science.gov (United States)

    2011-05-18

    ... AGENCY 40 CFR Parts 60 and 63 RIN 2060-AQ25; 2060-AO12 Industrial, Commercial, and Institutional Boilers and Process Heaters and Commercial and Industrial Solid Waste Incineration Units AGENCY: Environmental... Major Sources: Industrial, Commercial, and Institutional Boilers and Process Heaters'' and ``Standards...

  8. FLAME MONITORING IN POWER STATION BOILERS USING IMAGE PROCESSING

    Directory of Open Access Journals (Sweden)

    K. Sujatha

    2012-05-01

    Full Text Available Combustion quality in power station boilers plays an important role in minimizing the flue gas emissions. In the present work various intelligent schemes to infer the flue gas emissions by monitoring the flame colour at the furnace of the boiler are proposed here. Flame image monitoring involves capturing the flame video over a period of time with the measurement of various parameters like Carbon dioxide (CO2, excess oxygen (O2, Nitrogen dioxide (NOx, Sulphur dioxide (SOx and Carbon monoxide (CO emissions plus the flame temperature at the core of the fire ball, air/fuel ratio and the combustion quality. Higher the quality of combustion less will be the flue gases at the exhaust. The flame video was captured using an infrared camera. The flame video is then split up into the frames for further analysis. The video splitter is used for progressive extraction of the flame images from the video. The images of the flame are then pre-processed to reduce noise. The conventional classification and clustering techniques include the Euclidean distance classifier (L2 norm classifier. The intelligent classifier includes the Radial Basis Function Network (RBF, Back Propagation Algorithm (BPA and parallel architecture with RBF and BPA (PRBFBPA. The results of the validation are supported with the above mentioned performance measures whose values are in the optimal range. The values of the temperatures, combustion quality, SOx, NOx, CO, CO2 concentrations, air and fuel supplied corresponding to the images were obtained thereby indicating the necessary control action taken to increase or decrease the air supply so as to ensure complete combustion. In this work, by continuously monitoring the flame images, combustion quality was inferred (complete/partial/incomplete combustion and the air/fuel ratio can be automatically varied. Moreover in the existing set-up, measurements like NOx, CO and CO2 are inferred from the samples that are collected periodically or by

  9. Combustion Model FOr Staged Circulating Fluidized Bed BOiler

    Institute of Scientific and Technical Information of China (English)

    FandJianhua; LuQinggang; 等

    1997-01-01

    A mathematical model for atmospheric staged circulating fluidized bed combustion,which takes fluid dynamics,combustion,heat transfer,pollutants formation and retention,into account was developed in the institute of Engineering Thermophysics(IET)recently.The model of gas solid flow at the bottom of the combustor was treated by the two-phase theory of fluidized bed and in the upper region as a core-annulus flow structure.The chemical species CO,CO2,H2,H2O,CH4,O2 and N2 were considered in the reaction process.The mathematical model consisted of sub-modeles of fluid namics,coal heterogeneous and gas homogeneous chemical reactions.heat transfer,particle fragmentation and attrition,mass and energy balance tec.The developed code was applied to simulate an operating staged circulating fluidized bed combustion boiler of early design and the results were in good agreement with the operating data.The main submodels and simulation results are given in this paoper.

  10. Modeling Study of a New Circulating Fluidized Bi—Bed Boiler Combustion System

    Institute of Scientific and Technical Information of China (English)

    ZhaoJian; SuoYisheng; 等

    1999-01-01

    This paper presents a set of general dynamic mathematical models for the combustion system of a circulating fluidized bi-bed boiler,The models fully consider the flow.combustion and heat transfer characteristics,and describe the physical and chemical processes inside the bi-bed,including the gassolid flow.multiple particles combustion,gas chemical reactions,heat transfer and pressure balances.etc.

  11. FLAME MONITORING IN POWER STATION BOILERS USING IMAGE PROCESSING

    OpenAIRE

    K Sujatha; VENMATHI, M.; N. Pappa

    2012-01-01

    Combustion quality in power station boilers plays an important role in minimizing the flue gas emissions. In the present work various intelligent schemes to infer the flue gas emissions by monitoring the flame colour at the furnace of the boiler are proposed here. Flame image monitoring involves capturing the flame video over a period of time with the measurement of various parameters like Carbon dioxide (CO2), excess oxygen (O2), Nitrogen dioxide (NOx), Sulphur dioxide (SOx) and Carbon monox...

  12. Fuel moisture content analysis as a basis for process monitoring of a BioGrate boiler

    OpenAIRE

    Boriouchkine, Alexander; Zakharov, Alexey; Jämsä-Jounela, Sirkka-Liisa

    2010-01-01

    This paper considers the utilization of first principle models of a BioGrate boiler in a disturbance analysis study. The study focuses on the effect of fuel moisture content on the fuel combustion, since it is the most significant disturbance source in the boiler operation. The dynamic model of a BioGrate boiler, upon which the study is based, is heterogeneous, including solid and gas phases. Furthermore, the model considers chemical reactions in both gas and solid phases. In addition, fuel m...

  13. An optimization model for the operations of steam production in industrial boilers

    OpenAIRE

    Rocco,Cleber Damião; Morabito, Reinaldo

    2012-01-01

    In this study, a mixed integer linear programming model is presented to support some of the key decisions in the steam production system with industrial boilers. The model approaches the fuel management decisions (fuel replenishment and its inventory control), boiler operational decisions (start-up, warm-up, and shutdown operations), and which boiler should produce steam. The model adjustments and its validation were carried out through a case study in a large food industry. In face of the go...

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

    DEFF Research Database (Denmark)

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

    2003-01-01

    developed as a Differential-Algebraic-Equation system (DAE) and MATLAB has been applied for the integration of the models. In generalMATLAB has proved to be very stable for these DAE systems. Experimental verication has been carried out at a full scale plant equipped with instrumentation to verify heat....... The dynamic model has been developed for the purpose of determining boiler material temperatures and heat transfer from the ue gas side to the water-/steam side in order to simulate the circulation in the evaporator circuit and hereby the water level uctuations in the drum. The dynamic model has been...

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

    DEFF Research Database (Denmark)

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

    2003-01-01

    developed as a Differential-Algebraic-Equation system (DAE) and MATLAB has been applied for the integration of the models. In general MATLAB has proved to be very stable for these DAE systems. Experimental verification has been carried out at a full scale plant equipped with instrumentation to verify heat....... 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...

  16. Towards a generic, reliable CFD modelling methodology for waste-fired grate boilers

    DEFF Research Database (Denmark)

    Rajh, Boštjan; Yin, Chungen; Samec, Niko

    Computational Fluid Dynamics (CFD) is increasingly used in industry for detailed understanding of the combustion process and for appropriate design and optimization of Waste–to–Energy (WtE) plants. In this paper, CFD modelling of waste wood combustion in a 13 MW grate-fired boiler in a WtE plant...... the appropriate inlet boundary condition for the freeboard 3D CFD simulation. Additionally, a refined WSGGM (weighted sum of gray gases model) of greater accuracy, completeness and applicability is proposed and implemented into the CFD model via user defined functions (UDF) to better address the impacts...... is presented. To reduce the risk of slagging, optimize the temperature control and enhance turbulent mixing, part of the flue gas is recycled into the grate boiler. In the simulation, a 1D in–house bed model is developed to simulate the conversion of the waste wood in the fuel bed on the grate, which provides...

  17. The recovery boiler advisor. Combination of practical experience and advanced thermodynamic modelling

    Energy Technology Data Exchange (ETDEWEB)

    Backman, R. [Aabo Akademi, Turku (Finland); Eriksson, G. [LTH/RWTH (Germany); Sundstroem, K. [Tampella Power Oy, Tampere (Finland)

    1996-12-31

    The Aabo Advisor is a computer based program intended to provide information about the high temperature ash and fluegas chemistry in pulping spent black liquor recovery boilers of kraft pulp mills. The program can be used for predictions of a variety of furnace and flue gas phenomena, such as fireside fouling of the heat exchanger surfaces caused by the flue gas particulate matter, emissions of SO{sub 2}(g), HCl(g) and NO{sub x}(g) with the flue gas etc. The program determines the composition of the fluegas as well as the amount and composition of the two typical fly ash fractions found in recovery boiler fluegases, the condensed fly ash particles and the carry over particles. These data are used for calculating the melting behavior of the fly ash present at different locations in the boiler and this characteristic behavior is used for the fireside fouling predictions. The program may also be used for studying how different mill processes affecting the black liquor composition affects on the fireside chemistry of the recovery boiler. As input data for the calculations only a few boiler operation parameters and the composition of the black liquor is required. The calculations are based on a one-dimensional, multi-stage chemistry model where both thermodynamic equilibrium calculations and stoichiometric material balances are used. The model calculates at first the chemistry in the lower furnace and smelt after which it moves to the upper furnace and the radiative parts of the fluegas channel. As the last block the program calculates the chemistry in the convective part, the electrostatic precipitator cath and stack. The results from each block are presented in tables, key numbers and melt curves representing the fluegas or fly ash fraction present at each location

  18. Model prediction of the operating behavior of a circulating fluidized bed boiler

    Institute of Scientific and Technical Information of China (English)

    王勤辉; 骆仲泱; 倪明江; 岑可法

    2002-01-01

    An improved mathematical model for a circulating fluidized bed (CFB) boiler based on the model developed earlier by the authors was applied to simulate the operation of a 12 MW CFB boiler. The influences of the excess air ratio, primary air ratio, coal particle size distribution, coal properties (ash content and volatile content) and Ca/S ratio on the boiler operation were analyzed. The results showed that the model simulation may be applied to the optimum design and economic operation of the CFB boiler.

  19. Model prediction of the operating behavior of a circulating fluidized bed boiler

    Institute of Scientific and Technical Information of China (English)

    王勤辉; 骆仲泱; 倪明江; 岑可法

    2002-01-01

    An improved mathematical model for a circulating fluidized bed (CFB) boiler baaed on the model developed earlier by the authors was applied to simulate the operation of a 12 MW CFB boiler.The influences of the excess air ratio, primary air ratio, coal particle size distribution, coal properties (ash content and volatile content) and Ca/S ratio on the boiler operation were analyzed. The results showed that the model simulation may be applied to the optimum design and economic operation of the CFB boiler.

  20. Advanced char burnout models for the simulation of pulverized coal fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    T. Severin; S. Wirtz; V. Scherer [Ruhr-University, Bochum (Germany). Institute of Energy Plant Technology (LEAT)

    2005-07-01

    The numerical simulation of coal combustion processes is widely used as an efficient means to predict burner or system behaviour. In this paper an approach to improve CFD simulations of pulverized coal fired boilers with advanced coal combustion models is presented. In simple coal combustion models, first order Arrhenius rate equations are used for devolatilization and char burnout. The accuracy of such simple models is sufficient for the basic aspects of heat release. The prediction of carbon-in-ash is one aspect of special interest in the simulation of pulverized coal fired boilers. To determine the carbon-in-ash levels in the fly ash of coal fired furnaces, the char burnout model has to be more detailed. It was tested, in how far changing operating conditions affect the carbon-in-ash prediction of the simulation. To run several test cases in a short time, a simplified cellnet model was applied. To use a cellnet model for simulations of pulverized coal fired boilers, it was coupled with a Lagrangian particle model, used in CFD simulations, too. 18 refs., 5 figs., 5 tabs.

  1. Modelling Heat Exchangers for Domestic Boilers

    Directory of Open Access Journals (Sweden)

    S. F. C. F. Teixeira

    2000-01-01

    Full Text Available In the present paper the thermal behaviour of fin-tube heat exchangers is modeled. Particular attention has been given to the plate fins. The heat fluxes in the fins are described using a finite volume technique to discretize the energy equation. The thermal interactions with the water in the tubes and the surrounding air are treated as external boundaries, using appropriate relationships for forced convection in pipes and flat plates. The numerical results are presented in terms of dimensionless numbers (Fourier, Biot and geometric ratios which are found to be representative for this particular geometry. Furthermore, the effect of thermal gradients along the fin surface upon the fin efficiency is investigated. Based on a differential model for the heat balances, design charts have been developed for the thermal analysis of heat exchangers.

  2. Numerical modelling of lighting process in pulverized-coal burner of a boiler unit by the low-temperature plasma jet

    Energy Technology Data Exchange (ETDEWEB)

    Miloshevich, H.; Rychkov, A.D. [Siberian Branch of Russian Academy of Sciences, Novosibirsk (Russian Federation). Inst. of Occupational Technologies

    1999-07-01

    The authors numerically modelled the process of aeromixture ignition in a pulverized-coal burner by a central axysymmetric jet of air that is heated in an electrical are plasma generator up to about 5000 K. The aim was to investigate the process of coal particle ignition in the flow and establish the conditions under which the independent combustion of pulverized coal mixture occurs. The results obtained showed the important role of radiation heat transfer in initiating the combustion process of solid fuel particles. 8 refs., 5 figs.

  3. Study of connected system of automatic control of load and operation efficiency of a steam boiler with extremal controller on a simulation model

    Science.gov (United States)

    Sabanin, V. R.; Starostin, A. A.; Repin, A. I.; Popov, A. I.

    2017-02-01

    The problems of operation effectiveness increase of steam boilers are considered. To maintain the optimum fuel combustion modes, it is proposed to use an extremal controller (EC) determining the value of airflow rate, at which the boiler generating the desired amount of heat will consume a minimum amount of fuel. EC sets the determined value of airflow rate to airflow rate controller (ARC). The test results of numerical simulation dynamic nonlinear model of steam boiler with the connected system of automatic control of load and combustion efficiency using EC are presented. The model is created in the Simulink modeling package of MATLAB software and can be used to optimize the combustion modes. Based on the modeling results, the conclusion was drawn about the possibility in principle of simultaneously boiler load control and optimizing by EC the combustion modes when changing the fuel combustion heat and the boiler characteristics and its operating mode. It is shown that it is possible to automatically control the operation efficiency of steam boilers when using EC without applying the standard flue gas analyzers. The article considers the numerical simulation dynamic model of steam boiler with the schemes of control of fuel consumption and airflow rate, the steam pressure and EC; the purpose of using EC in the scheme with linear controllers and the requirements to the quality of its operation; the results of operation of boiler control schemes without EC with estimation of influence of roughness of thermal mode maps on the nature of static and dynamic connection of the control units of fuel consumption and airflow rate; the phase trajectories and the diagrams of transient processes occurring in the control scheme with EC with stepped changing the fuel quality and boiler characteristics; analysis of modeling results and prospects for using EC in the control schemes of boilers.

  4. Modelling of boiler heating surfaces and evaporator circuits

    DEFF Research Database (Denmark)

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

    2002-01-01

    the circulation in the evaporator circuit. The models have been developed as Differential-Algebraic-Equations (DAE) and MATLAB has been applied for the integration of the models. In general MATLAB has proved to be very stable for the relatively stiff equation systems. Experimental verification is planned......Dynamic models for simulating boiler performance have been developed. Models for the flue gas side and for the evaporator circuit have been developed for the purpose of determining material temperatures and heat transfer from the flue gas side to the water-/steam side in order to simulate...... at a full scale plant equipped with instrumentation to verify heat transfer and circulation in the evaporator circuit....

  5. Modelling of Boiler Heating Surfaces and Evaporator Circuits

    DEFF Research Database (Denmark)

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

    2002-01-01

    the circulation in the evaporator circuit. The models have been developed as Differential-Algebraic-Equation systems (DAE) and MATLAB has been applied for the integration of the models. In general MATLAB has proved to be very stable for these relatively stiff equation systems. Experimental verication is planned......Dynamic models for simulating boiler performance have been developed. Models for the ue gas side and for the evaporator circuit have been developed for the purpose of determining material temperatures and heat transfer from the ue gas side to the water-/steam side in order to simulate...... at a full scale plant equipped with instrumentation to verify heat transfer and circulation in the evaporator circuit....

  6. 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.

  7. Characteristics modeling for supercritical circulating fluidized bed boiler working in oxy-combustion technology

    Science.gov (United States)

    Balicki, Adrian; Bartela, Łukasz

    2014-06-01

    Among the technologies which allow to reduce greenhouse gas emission, mainly carbon dioxide, special attention deserves the idea of `zeroemission' technology based on boilers working in oxy-combustion technology. In the paper the results of analyses of the influence of changing two quantities, namely oxygen share in oxidant produced in the air separation unit, and oxygen share in oxidant supplied to the furnace chamber on the selected characteristics of a steam boiler including the degree of exhaust gas recirculation, boiler efficiency and adiabatic flame temperature, was examined. Due to the possibility of the integration of boiler model with carbon dioxide capture, separation and storage installation, the subject of the analysis was also to determine composition of the flue gas at the outlet of a moisture condensation installation. Required calculations were made using a model of a supercritical circulating fluidized bed boiler working in oxy-combustion technology, which was built in a commercial software and in-house codes.

  8. Research of power fuel low-temperature vortex combustion in industrial boiler based on numerical modelling

    Directory of Open Access Journals (Sweden)

    Orlova K.Y.

    2017-01-01

    Full Text Available The goal of the presented research is to perform numerical modelling of fuel low-temperature vortex combustion in once-through industrial steam boiler. Full size and scaled-down furnace model created with FIRE 3D software and was used for the research. All geometrical features were observed. The baseline information for the low-temperature vortex furnace process are velocity and temperature of low, upper and burner blast, air-fuel ratio, fuel consumption, coal dust size range. The obtained results are: temperature and velocity three dimensional fields, furnace gases and solid fuel ash particles concentration.

  9. Super Boiler 2nd Generation Technology for Watertube Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Mr. David Cygan; Dr. Joseph Rabovitser

    2012-03-31

    This report describes Phase I of a proposed two phase project to develop and demonstrate an advanced industrial watertube boiler system with the capability of reaching 94% (HHV) fuel-to-steam efficiency and emissions below 2 ppmv NOx, 2 ppmv CO, and 1 ppmv VOC on natural gas fuel. The boiler design would have the capability to produce >1500 F, >1500 psig superheated steam, burn multiple fuels, and will be 50% smaller/lighter than currently available watertube boilers of similar capacity. This project is built upon the successful Super Boiler project at GTI. In that project that employed a unique two-staged intercooled combustion system and an innovative heat recovery system to reduce NOx to below 5 ppmv and demonstrated fuel-to-steam efficiency of 94% (HHV). This project was carried out under the leadership of GTI with project partners Cleaver-Brooks, Inc., Nebraska Boiler, a Division of Cleaver-Brooks, and Media and Process Technology Inc., and project advisors Georgia Institute of Technology, Alstom Power Inc., Pacific Northwest National Laboratory and Oak Ridge National Laboratory. Phase I of efforts focused on developing 2nd generation boiler concepts and performance modeling; incorporating multi-fuel (natural gas and oil) capabilities; assessing heat recovery, heat transfer and steam superheating approaches; and developing the overall conceptual engineering boiler design. Based on our analysis, the 2nd generation Industrial Watertube Boiler when developed and commercialized, could potentially save 265 trillion Btu and $1.6 billion in fuel costs across U.S. industry through increased efficiency. Its ultra-clean combustion could eliminate 57,000 tons of NOx, 460,000 tons of CO, and 8.8 million tons of CO2 annually from the atmosphere. Reduction in boiler size will bring cost-effective package boilers into a size range previously dominated by more expensive field-erected boilers, benefiting manufacturers and end users through lower capital costs.

  10. Processing of Egyptian boiler-ash for extraction of vanadium and nickel.

    Science.gov (United States)

    Amer, A M

    2002-01-01

    Proposed technique in this investigation is given for vanadium and nickel enrichment in the Egyptian boiler ash. Among the various concepts for recovery of vanadium and nickel from boiler ash, the pyro-metallurgical approach is technically feasible, but is not cost-effective from an operational economy standpoint. Another technically viable process which, however, needs further development and presented in this investigation, is the hydrometallurgical processing that involves acid leaching under oxygen pressure of ground ash, followed by electrolytic separation of nickel from sulphate solution and vanadium is then neutralized and precipitated by adjustment the pH value and calcined to produce V2O5.

  11. Numerical modelling of a straw-fired grate boiler

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen

    2004-01-01

    The paper presents a computational fluid dynamics (CFD) analysis of a 33 MW straw-fired grate boiler. Combustion on the grate plays akey-role in the analysis of these boilers and in this work a stand-alone code was used to provide inlet conditions for the CFD analysis. Modelpredictions were...... compared with available gas temperature and species concentration measurements showing good agreement. Combustionof biomass in grate-based boilers is often associated with high emission levels and relatively high amounts of unburnt carbon in the fly ash.Based on the CFD analysis, it is suggested that poor...

  12. Results from studies of furnace processes in boilers constructed on the basis of vortex combustion technology

    Science.gov (United States)

    Salomatov, V. V.

    2012-06-01

    The main results obtained from experimental and numerical simulation of furnace processes and emission of toxic substances during the firing of low-grade coals, in particular, in a steam generator equipped with the vortex furnace designed by N.V. Golovanov from the Central Boiler-Turbine Institute, are presented. A set of research works carried out at the modern level made it possible to work out recommendations for making further improvements in the design and operating characteristics of boilers equipped with a vortex furnace.

  13. Study on Cracking Process of Power Boiler Element

    Science.gov (United States)

    Mutwil, K.; Cieśla, M.

    2012-05-01

    This paper presents the study of the reasons for cracking of spray steam attemperator. The element being analysed is a temperature controller of steam for turbine; its proper functioning has considerable impact on operation of power generating set of boiler and turbine. Damage to the steam attemperator may affect the durability of neighbouring components, replacement or repair of which results in a long-term outage of power generation unit. The reason for attemperator cracking has been determined on the basis of strength calculations and micro-and macro-analysis of fracture surfaces. The conducted tests were the basis for modification of attemperator design, which will ensure reliable functioning of the analysed element.

  14. A Novel Modelling Approach for Condensing Boilers Based on Hybrid Dynamical Systems

    Directory of Open Access Journals (Sweden)

    Harish Satyavada

    2016-04-01

    Full Text Available Condensing boilers use waste heat from flue gases to pre-heat cold water entering the boiler. Flue gases are condensed into liquid form, thus recovering their latent heat of vaporization, which results in as much as 10%–12% increase in efficiency. Modeling these heat transfer phenomena is crucial to control this equipment. Despite the many approaches to the condensing boiler modeling, the following shortcomings are still not addressed: thermal dynamics are oversimplified with a nonlinear efficiency curve (which is calculated at steady-state; the dry/wet heat exchange is modeled in a fixed proportion. In this work we cover these shortcomings by developing a novel hybrid dynamic model which avoids the static nonlinear efficiency curve and accounts for a time-varying proportion of dry/wet heat exchange. The procedure for deriving the model is described and the efficiency of the resulting condensing boiler is shown.

  15. Fruit fly optimization algorithm based high efficiency and low NOx combustion modeling for a boiler

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhenxing∗; SUN Baomin; XIN Jing

    2014-01-01

    In order to control NOx emissions and enhance boiler efficiency in coal-fired boilers,the thermal operating data from an ultra-supercritical 1 000 MW unit boiler were analyzed.On the basis of the support vector regression machine (SVM),the fruit fly optimization algorithm (FOA)was applied to optimize the penalty parameter C,ker-nel parameter g and insensitive loss coefficient of the model.Then,the FOA-SVM model was established to predict the NOx emissions and boiler efficiency,and the performance of this model was compared with that of the GA-SVM model optimized by genetic algorithm (GA).The results show the FOA-SVM model has better prediction accuracy and generalization capability,of which the maximum average relative error of testing set lies in the NOx emissions model,which is only 3 .5 9%.The above models can predict the NOx emissions and boiler efficiency accurately,so they are very suitable for on-line modeling prediction,which provides a good model foundation for further optimiza-tion operation of large capacity boilers.

  16. Mathematical modeling and experimental study of biomass combustion in a thermal 108 MW grate-fired boiler

    DEFF Research Database (Denmark)

    Yin, Chungen; Rosendahl, Lasse; Kær, Søren K.

    2008-01-01

    on the basis of the sensitivity analysis and the measurements. The baseline results show an overall acceptable agreement with the measured data and the site observations, indicating the baseline model is applicable in optimization of the boiler and design of new grate boilers. However, at a few measuring...... computational fluid dynamics (CFD) model for an industrial biomass-fired grate boiler, which can be used for diagnosis and optimization of the grate boiler as well as design of new grate boilers. First, based on the design conditions, a thorough sensitivity analysis is done to evaluate the relative importance...... of different factors in CFD analysis of the grate boiler. In a late stage, a two-day measuring campaign is carried out to measure the gas temperatures and gas concentrations in the boiler using a fiber optic probe connected to a Fourier transform infrared (FTIR) spectrometer. A baseline model is then defined...

  17. 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.

  18. 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.

  19. Central heating: package boilers

    Energy Technology Data Exchange (ETDEWEB)

    Farahan, E.

    1977-05-01

    Performance and cost data for electrical and fossil-fired package boilers currently available from manufacturers are provided. Performance characteristics investigated include: unit efficiency, rated capacity, and average expected lifetime of units. Costs are tabulated for equipment and installation of various package boilers. The information supplied in this report will simplify the process of selecting package boilers required for industrial, commercial, and residential applications.

  20. Modeling energy consumption of residential furnaces and boilers in U.S. homes

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, James; Dunham-Whitehead, Camilla; Lekov, Alex; McMahon, James

    2004-02-01

    In 2001, DOE initiated a rulemaking process to consider whether to amend the existing energy efficiency standards for furnaces and boilers. A key factor in DOE's consideration of new standards is their cost-effectiveness to consumers. Determining cost-effectiveness requires an appropriate comparison of the additional first cost of energy efficiency design options with the savings in operating costs. This report describes calculation of equipment energy consumption (fuel and electricity) based on estimated conditions in a sample of homes that are representative of expected furnace and boiler installations. To represent actual houses with furnaces and boilers in the United States, we used a set of houses from the Residential Energy Consumption Survey of 1997 conducted by the Energy Information Administration. Our calculation methodology estimates the energy consumption of alternative (more-efficient) furnaces, if they were to be used in each house in place of the existing equipment. We developed the method of calculation described in this report for non-weatherized gas furnaces. We generalized the energy consumption calculation for this product class to the other furnace product classes. Fuel consumption calculations for boilers are similar to those for the other furnace product classes. The electricity calculations for boilers are simpler than for furnaces, because boilers do not provide thermal distribution for space cooling as furnaces often do.

  1. Constrained optimization of combustion in a simulated coal-fired boiler using artificial neural network model and information analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ji-Zheng Chu; Shyan-Shu Shieh; Shi-Shang Jang; Chuan-I Chien; Hou-Peng Wan; Hsu-Hsun Ko [Beijing University of Chemical Technology, Beijing (China). Department of Automation

    2003-04-01

    Combustion in a boiler is too complex to be analytically described with mathematical models. To meet the needs of operation optimization, on-site experiments guided by the statistical optimization methods are often necessary to achieve the optimum operating conditions. This study proposes a new constrained optimization procedure using artificial neural networks as models for target processes. Information analysis based on random search, fuzzy c-mean clustering, and minimization of information free energy is performed iteratively in the procedure to suggest the location of future experiments, which can greatly reduce the number of experiments needed. The effectiveness of the proposed procedure in searching optima is demonstrated by three case studies: (1) a bench-mark problem, namely minimization of the modified Himmelblau function under a circle constraint; (2) both minimization of NOx and CO emissions and maximization of thermal efficiency for a simulated combustion process of a boiler; (3) maximization of thermal efficiency within NOx and CO emission limits for the same combustion process. The simulated combustion process is based on a commercial software package CHEMKIN, where 78 chemical species and 467 chemical reactions related to the combustion mechanism are incorporated and a plug-flow model and a load-correlated temperature distribution for the combustion tunnel of a boiler are used. 22 refs., 6 figs., 4 tabs.

  2. A Model for Optimization and Analysis of Energy Flexible Boiler Plants for Building Heating Purposes

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, J.R.

    1996-05-01

    This doctoral thesis presents a model for optimization and analysis of boiler plants. The model optimizes a boiler plant with respect to the annual total costs or with respect to energy consumption. The optimum solution is identified for a given number of energy carriers and defined characteristics of the heat production units. The number of heat production units and the capacity of units related to each energy carrier or the capacity of units related to the same energy carrier can be found. For a problem comprising large variation during a defined analysis period the model gives the operating costs and energy consumption to be used in an extended optimization. The model can be used to analyse the consequences with respect to costs and energy consumption due to capacity margins and shifts in the boundary conditions. The model is based on a search approach comprising an operational simulator. The simulator is based on a marginal cost method and dynamic programming. The simulation is performed on an hourly basis. A general boiler characteristic representation is maintained by linear energy or cost functions. The heat pump characteristics are represented by tabulated performance and efficiency as function of state and nominal aggregate capacities. The simulation procedure requires a heat load profile on an hourly basis. The problem of the presence of capacity margins in boiler plants is studied for selected cases. The single-boiler, oil-fired plant is very sensitive to the magnitude of the losses present during burner off-time. For a plant comprising two oil-fired burners, the impact of a capacity margin can be dampened by the selected capacity configuration. The present incentive, in Norway, to install an electric element boiler in an oil-fired boiler plant is analysed. 77 refs., 74 figs., 12 tabs.

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

    Science.gov (United States)

    2012-07-01

    replacement of the existing butterfly valve assembly with a servomotor-driven valve assembly for both the fuel and air linkages. This process is...monitoring of flue gas concentrations of O2 and CO to improve the boiler fuel-to-steam efficiency by means of regulation of the burner inlet fuel valve ...to upgrading the combustion control systems consists of substituting the mechanical linkage between the air inlet damper and the fuel inlet valve

  4. Modeling of the buckstay system of membrane-walls in watertube boiler construction

    Directory of Open Access Journals (Sweden)

    Nagiar Hasan Mehdi

    2014-01-01

    Full Text Available Membrane walls are very important structural parts of water-tube boiler construction. Based on their specific geometry, one special type of finite element was defined to help model the global boiler construction. That is the element of reduced orthotropic plate with two thicknesses and two elasticity matrixes, for membrane and bending load separately. A global model of the boiler construction showed that the high value of stress is concentrated in plates of the buckstay system in boiler corners. Validation of the new finite element was done on the local model of the part of membrane wall and buckstay. A very precise model of tubes and flanges was compared to the model formed on the element of a reduced orthotropic plate. Pressure and thermal loads were discussed. Obtained results indicated that the defined finite element was quite favorable in the design and reconstruction of the boiler substructures such as a buckstay system. [Projekat Ministarstva nauke Republike Srbije, br. TR 35040 i br. TR 35011

  5. Technical and economic feasibility of alternative fuel use in process heaters and small boilers

    Energy Technology Data Exchange (ETDEWEB)

    1980-02-01

    The technical and economic feasibility of using alternate fuels - fuels other than oil and natural gas - in combustors not regulated by the Powerplant and Industrial Fuel Use Act of 1978 (FUA) was evaluated. FUA requires coal or alternate fuel use in most large new boilers and in some existing boilers. Section 747 of FUA authorizes a study of the potential for reduced oil and gas use in combustors not subject to the act: small industrial boilers with capacities less than 100 MMBtu/hr, and process heat applications. Alternative fuel use in combustors not regulated by FUA was examined and the impact of several measures to encourage the substitution of alternative fuels in these combustors was analyzed. The primary processes in which significant fuel savings can be achieved are identified. Since feedstock uses of oil and natural gas are considered raw materials, not fuels, feedstock applications are not examined in this analysis. The combustors evaluated in this study comprise approximately 45% of the fuel demand projected in 1990. These uses would account for more than 3.5 million barrels per day equivalent fuel demand in 1990.

  6. 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.

  7. Mathematical modelling of full scale combustion in front wall fired boiler of EDP

    Energy Technology Data Exchange (ETDEWEB)

    Azevedo, J.L.T.; Coelho, L.M.R.; Carvalho, M.G. [Instituto Superior Tecnico, Lisbon (Portugal)

    1998-12-31

    Numerical modelling of pulverised coal combustion is applied to simulate front wall fired utility boilers to analyse the influence of air staging (using rows of burners out of service BOOS) or combined fuel and air staging (reburning). The NO{sub x} post processor of an existing numerical model is modified to consider these conditions and calculations are applied to two utility boilers. For the case of using BOOS the model indicates NO{sub x} reductions from 5 to 12% while for reburning the NO{sub x} emissions resulting from coal are reduced by 28%. The analysis of the results address besides the NO{sub x} emissions the amount of carbon in ash and the heat flux distribution in the boiler walls and superheater panels. 22 refs., 13 figs., 7 tabs.

  8. Characteristics modeling for supercritical circulating fluidized bed boiler working in oxy-combustion technology

    Directory of Open Access Journals (Sweden)

    Balicki Adrian

    2014-06-01

    Full Text Available Among the technologies which allow to reduce greenhouse gas emission, mainly carbon dioxide, special attention deserves the idea of ‘zeroemission’ technology based on boilers working in oxy-combustion technology. In the paper the results of analyses of the influence of changing two quantities, namely oxygen share in oxidant produced in the air separation unit, and oxygen share in oxidant supplied to the furnace chamber on the selected characteristics of a steam boiler including the degree of exhaust gas recirculation, boiler efficiency and adiabatic flame temperature, was examined. Due to the possibility of the integration of boiler model with carbon dioxide capture, separation and storage installation, the subject of the analysis was also to determine composition of the flue gas at the outlet of a moisture condensation installation. Required calculations were made using a model of a supercritical circulating fluidized bed boiler working in oxy-combustion technology, which was built in a commercial software and in-house codes.

  9. A practical predictive control algorithm for integral processes and a case study in boiler level system

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The Dynamic Matrix Control (DMC) algorithm for integral processes is investigated in this paper. The reason why the original DMC algorithm cannot be applied to these processes is analyzed. The shifting matrix is transformed into another form and the corresponding theorem is proved, then its applicable range is extended. Compared with other algorithms on the integral processes, this algorithm is more practical and simple to implement. Simulation results also prove its validity. Applying this algorithm, we succeed in the control of the boiler level system in power units.

  10. Developing Boiler Concepts as Integrated Units

    DEFF Research Database (Denmark)

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

    2004-01-01

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

  11. Low Load Model of a Once-through Boiler with Recirculation

    DEFF Research Database (Denmark)

    Trangbæk, Klaus

    2006-01-01

    A dynamic simulation model of a once-through boiler in low to medium load is developed. When the system is in low load, water from the evaporator is recirculated through a bottle. This recirculation system is included in the model, which is then shown to fit closed-loop data from a real plant...

  12. Numerical Calculations of WR-40 Boiler Based on its Zero-Dimensional Model

    Directory of Open Access Journals (Sweden)

    Hernik Bartłomiej

    2014-06-01

    Full Text Available Generally, the temperature of flue gases at the furnace outlet is not measured. Therefore, a special computation procedure is needed to determine it. This paper presents a method for coordination of the numerical model of a pulverised fuel boiler furnace chamber with the measuring data in a situation when CFD calculations are made in regard to the furnace only. This paper recommends the use of the classical 0-dimensional balance model of a boiler, based on the use of measuring data. The average temperature of flue gases at the furnace outlet tk" obtained using the model may be considered as highly reliable. The numerical model has to show the same value of tk" . This paper presents calculations for WR-40 boiler. The CFD model was matched to the 0-dimensional tk" value by means of a selection of the furnace wall emissivity. As a result of CFD modelling, the flue gas temperature and the concentration of CO, CO2, O2 and NOx were obtained at the furnace chamber outlet. The results of numerical modelling of boiler combustion based on volumetric reactions and using the Finite-Rate/Eddy-Dissipation Model are presented.

  13. Black liquor combustion validated recovery boiler modeling: Final year report. Volume 4 (Appendix IV)

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-08-01

    This project was initiated in October 1990, with the objective of developing and validating 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 key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 4 contains the following appendix sections: Radiative heat transfer properties for black liquor combustion -- Facilities and techniques and Spectral absorbance and emittance data; and Radiate heat transfer determination of the optical constants of ash samples from kraft recovery boilers -- Calculation procedure; Computation program; Density determination; Particle diameter determination; Optical constant data; and Uncertainty analysis.

  14. Mathematical Model for Predicting Corrosion Rates in Furnace Internal Wall Tubes of The Refinery Boiler

    Directory of Open Access Journals (Sweden)

    Edori, E. S

    2016-08-01

    Full Text Available A model for predicting the corrosion rates in the furnace internal wall tubes of the refinery boiler was resolved, using the first order differential equation derived from the material balance equation of the system. The mathematical model was able to predict the metal loss recorded by ultrasonic thickness scanning technique (UTS, and the results shows an agreement. The results from both the model and UTS shows that in the various tubes of the furnace, internal wall of the refinery boiler were between the same range. The percentage deviation which was calculated to ascertain the acceptability of the model result as compared to that from UTS proved that the model is effective. The inhibitor model result show that corrosion will drastically reduce in the presence of corrosion inhibitors under proper chemical treatment and management. The model developed can be used to monitor furnace internal wall corrosion even when the system is in operation by extrapolating the result to further years.

  15. Modeling and experiments of biomass combustion in a large-scale grate boiler

    DEFF Research Database (Denmark)

    Yin, Chungen; Rosendahl, Lasse; Kær, Søren Knudsen

    2007-01-01

    and experiments are both done for the grate boiler. The comparison between them shows an overall acceptable agreement in tendency. However at some measuring ports, big discrepancies between the modeling and the experiments are observed, mainly because the modeling-based boundary conditions (BCs) could differ...... is exposed to preheated inlet air while the top of the bed resides within the furnace. Mathematical modeling is an efficient way to understand and improve the operation and design of combustion systems. Compared to modeling of pulverized fuel furnaces, CFD modeling of biomass-fired grate furnaces...... is inherently more difficult due to the complexity of the solid biomass fuel bed on the grate, the turbulent reacting flow in the combustion chamber and the intensive interaction between them. This paper presents the CFD validation efforts for a modern large-scale biomass-fired grate boiler. Modeling...

  16. Burnout of pulverized biomass particles in large scale boiler - Single particle model approach

    Energy Technology Data Exchange (ETDEWEB)

    Saastamoinen, Jaakko; Aho, Martti; Moilanen, Antero [VTT Technical Research Centre of Finland, Box 1603, 40101 Jyvaeskylae (Finland); Soerensen, Lasse Holst [ReaTech/ReAddit, Frederiksborgsveij 399, Niels Bohr, DK-4000 Roskilde (Denmark); Clausen, Soennik [Risoe National Laboratory, DK-4000 Roskilde (Denmark); Berg, Mogens [ENERGI E2 A/S, A.C. Meyers Vaenge 9, DK-2450 Copenhagen SV (Denmark)

    2010-05-15

    Burning of coal and biomass particles are studied and compared by measurements in an entrained flow reactor and by modelling. The results are applied to study the burning of pulverized biomass in a large scale utility boiler originally planned for coal. A simplified single particle approach, where the particle combustion model is coupled with one-dimensional equation of motion of the particle, is applied for the calculation of the burnout in the boiler. The particle size of biomass can be much larger than that of coal to reach complete burnout due to lower density and greater reactivity. The burner location and the trajectories of the particles might be optimised to maximise the residence time and burnout. (author)

  17. Burnout of pulverized biomass particles in large scale boiler – Single particle model approach

    DEFF Research Database (Denmark)

    Saastamoinen, Jaakko; Aho, Martti; Moilanen, Antero

    2010-01-01

    the particle combustion model is coupled with one-dimensional equation of motion of the particle, is applied for the calculation of the burnout in the boiler. The particle size of biomass can be much larger than that of coal to reach complete burnout due to lower density and greater reactivity. The burner...... location and the trajectories of the particles might be optimised to maximise the residence time and burnout....

  18. Analytical model for erosion behaviour of impacted fly-ash particles on coal-fired boiler components

    Indian Academy of Sciences (India)

    S K Das; K M Godiwalla; S P Mehrotra; K K M Sastry; P K Dey

    2006-10-01

    Fly ash particles entrained in the flue gas from boiler furnaces in coal-fired power stations can cause serious erosive wear on steel surfaces along the flow path. Such erosion can significantly reduce the operational life of the boiler components. A mathematical model embodying the mechanisms of erosion on behaviour, has been developed to predict erosion rates of coal-fired boiler components at different temperatures. Various grades of steels used in fabrication of boiler components and published data pertaining to boiler fly ash have been used for the modelling. The model incorporates high temperature tensile properties of the target metal surface at room and elevated temperatures and has been implemented in an user-interactive in-house computer code (EROSIM–1), to predict the erosion rates of various grades of steel. Predictions have been found to be in good agreement with the published data. The model is calibrated with plant and experimental data generated from a high temperature air-jet erosion-testing facility. It is hoped that the calibrated model will be useful for erosion analysis of boiler components.

  19. Analytical model for erosion behaviour of impacted fly-ash particles on coal-fired boiler components

    Energy Technology Data Exchange (ETDEWEB)

    Das, S.K.; Godiwalla, K.M.; Mehrotra, S.P.; Sastry, K.K.M.; Dey, P.K.

    2006-10-15

    Fly ash particles entrained in the flue gas from boiler furnaces in coal-fired power stations can cause serious erosive wear on steel surfaces along the flow path. Such erosion can significantly reduce the operational life of the boiler components. A mathematical model, embodying the mechanisms of erosion on behaviour, has been developed to predict erosion rates of coal-fired boiler components at different temperatures. Various grades of steels used in fabrication of boiler components and published data pertaining to boiler fly ash have been used for the modelling. The model incorporates high temperature tensile properties of the target metal surface at room and elevated temperatures and has been implemented in an user-interactive in-house computer code (EROSIM-1), to predict the erosion rates of various grades of steel. Predictions have been found to be in good agreement with the published data. The model is calibrated with plant and experimental data generated from a high temperature air-jet erosion-testing facility. It is hoped that the calibrated model will be useful for erosion analysis of boiler components.

  20. Study of thermal-flow processes in ash cooler cooperating with CFB boiler

    Directory of Open Access Journals (Sweden)

    Paweł Regucki

    2016-03-01

    Full Text Available The article presents an example of thermal-flow analysis of the bottom ash cooler cooperating with the circulating fluidized bed boiler. There is presented a mathematical model of series-parallel hydraulic system supplying the ash cooler in cooling water. The numerical calculations indicate an influence of changes of the pipeline geometrical parameters on the cooling water flow rate in the system. Paper discusses the methodology of the studies and presents examples of the results of thermal balance calculations based on the results of measurements. The numerical results of the thermal-flow analysis in comparison with the measurements on the object indicate that the presented approach could be used as a diagnostic tool investigating the technical state of the bottom ash cooler.

  1. Thermodynamic analysis and kinetic modelling of dioxin formation and emissions from power boilers firing salt-laden hog fuel.

    Science.gov (United States)

    Duo, Wenli; Leclerc, Denys

    2007-04-01

    Both organic chlorine (e.g. PVC) and inorganic chlorides (e.g. NaCl) can be significant chlorine sources for dioxin and furan (PCDD/F) formation in combustion processes. This paper presents a thermodynamic analysis of high temperature salt chemistry. Its influence on PCDD/F formation in power boilers burning salt-laden wood waste is examined through the relationships between Cl2, HCl, NaCl(g) and NaCl(c). These analyses show that while HCl is a product of combustion of PVC-laden municipal solid waste, NaCl can be converted to HCl in hog fuel boilers by reactions with SO2 or alumino-silicate materials. Cl2 is a strong chlorinating agent for PCDD/F formation. HCl can be oxidized to Cl2 by O2, and Cl2 can be reduced back to HCl by SO2. The presence of sulphur at low concentrations thus enhances PCDD/F formation by increasing HCl concentrations. At high concentrations, sulphur inhibits de novo formation of PCDD/Fs through Cl2 reduction by excess SO2. The effect of NH3, CO and NOx on PCDD/F formation is also discussed. A semi-empirical kinetic model is proposed. This model considers both precursor and de novo formation mechanisms. A simplified version is used as a stack emission model. The kinetic model indicates that stack dioxin emissions will increase linearly with decreasing electrostatic precipitator (ESP) efficiency and exponentially with increasing ESP temperature.

  2. Physical and combustion characteristics of biomass particles prepared by different milling processes for suspension firing in utility boilers

    DEFF Research Database (Denmark)

    Yin, Chungen; Momenikouchaksaraei, Maryam; Kær, Søren Knudsen

    2016-01-01

    close to suspension-fired boilers. The ignition, devolatilization and burnout times of the milled particles under different combustion conditions are analysed. A one-dimensional transient model, properly accounting for the particle-ambient flow interaction and appropriately addressing the key sub...

  3. 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.

  4. The real time cascade generalized predictive control and application to a boiler circuit system

    Institute of Scientific and Technical Information of China (English)

    Xu Min; Li Shaoyuan

    2005-01-01

    Boiler-circuit system in a circulating fluidized bed combustion boiler is a complex and typical industrial process with a large lag and time-delay. Conventional PID algorithm can not obtain satisfied performance, especially in the presence of disturbance. A cascade generalized predictivecontrol (CGPC) strategy, is which the inner loop can restrain the disturbance while the outer loop can eliminate the offset, is proposed in this paper. We develop cascade GPC algorithm instead of conventional PID algorithm in the boiler-circuit system. Simulation on experimental boiler-circuit models of circulating fluidized bed combustion boiler shows strong robustness.

  5. Boiler-turbine control system design using continuous-time nonlinear model predictive control

    Institute of Scientific and Technical Information of China (English)

    ZHUO Xu-sheng; ZHOU Huai-chun

    2008-01-01

    A continuous-time nonlinear model predictive controller (NMPC) was designed for a boiler-turbine unit. The controller was designed by optimizing a receding-horizon performance index, with the nonlinear system approximated by its Taylor series expansion with a certain order, the magnitude saturation constraints on the inputs satisfied by increasing the predictive time, and the rate saturation conditions on the actuators satisfied by tuning the time constant of the reference trajectories in a reference governor. Simulation results showed that the controller can drive the drum pressure and output power of the nonlinear boiler-turbine unit to follow their respective reference trajectories throughout a varying operation range and keep the water level deviation within tolerances. Comparison of the NMPC scheme with the generic model control (GMC) scheme indicated that the responses are slower and there are more oscillations in the responses of the water level, fuel flow input and feed water flow input in the GMC scheme when the boiler-turbine unit is operating over a wide range.

  6. Estimation of Scale Deposition in the Water Walls of an Operating Indian Coal Fired Boiler: Predictive Modeling Approach Using Artificial Neural Networks

    Science.gov (United States)

    Kumari, Amrita; Das, Suchandan Kumar; Srivastava, Prem Kumar

    2016-04-01

    Application of computational intelligence for predicting industrial processes has been in extensive use in various industrial sectors including power sector industry. An ANN model using multi-layer perceptron philosophy has been proposed in this paper to predict the deposition behaviors of oxide scale on waterwall tubes of a coal fired boiler. The input parameters comprises of boiler water chemistry and associated operating parameters, such as, pH, alkalinity, total dissolved solids, specific conductivity, iron and dissolved oxygen concentration of the feed water and local heat flux on boiler tube. An efficient gradient based network optimization algorithm has been employed to minimize neural predictions errors. Effects of heat flux, iron content, pH and the concentrations of total dissolved solids in feed water and other operating variables on the scale deposition behavior have been studied. It has been observed that heat flux, iron content and pH of the feed water have a relatively prime influence on the rate of oxide scale deposition in water walls of an Indian boiler. Reasonably good agreement between ANN model predictions and the measured values of oxide scale deposition rate has been observed which is corroborated by the regression fit between these values.

  7. OPTIMIZATION OF TRANSIEN PROCESSES OF WATER LEVEL VARIATION IN DRUM OF STEAM BOILERS

    Directory of Open Access Journals (Sweden)

    G. T. Kulakov

    2014-01-01

    Full Text Available The work of regulator in general three-impulse automatic control system of water level in drum of boiler doesn’t supply quality of internal and external disturbance attack (presentation of regulation mistakes. That is why it is needed to improve. Different methods of proportional plus reset controller regulation of three-phase automatic feed control system are considered. There were suggested new methods to improve the quality of regulation of water level in boilers. Here the step system of automatic regulation was determined, on the base of transfer function.It is noticed that optimal transient processes supply calculation of numerical value of transmission factor of regulator at g =2,618, it is more then was recommended, but statistic mistakes remain. The transient simulation method in fast-time scale is recommended, this allow to determine early the value of statistic mistake of regulation by disturbances of reheated steam consumption and properly change the task to compensating device of step automatic control system. And numerical value of time constant criteria  should be calculated on the base of numbers of golden section(Phi, taking into account the definite time constant of lead section and time-lag, time-lag on controlled influence channel, and also taking into account maximum value of controlled influence. This method allow to reduce in two times the total time of regulation, to decrease absolute mistake of regulation in three times, and maximum value of regulation influence by feedwater in 1,7 times.

  8. Experimental determination of temperatures of the inner wall of a boiler combustion chamber for the purpose of verification of a CFD model

    Directory of Open Access Journals (Sweden)

    Petr Trávníček

    2011-01-01

    Full Text Available The paper focuses on the non-destructive method of determination of temperatures in the boiler combustion chamber. This method proves to be significant mainly as regards CFD (Computational Fluid Dynamics simulations of combustion processes, in case of which it is subsequently advisable to verify the data calculated using CFD software application with the actually measured data. Verification of the method was based on usage of reference combustion equipment (130 kW which performs combustion of a mixture of waste sawdust and shavings originating in the course of production of wooden furniture. Measuring of temperatures inside the combustion chamber is – considering mainly the high temperature values – highly demanding and requires a special type of temperature sensors. Furthermore, as regards standard operation, it is not possible to install such sensors without performing structural alterations of the boiler. Therefore, for the purpose of determination of these temperatures a special experimental device was constructed while exploiting a thermal imaging system used for monitoring of the surface temperature of outer wall of the reference boiler. Temperatures on the wall of the boiler combustion chamber were determined on the basis of data measured using the experimental device as well as data from the thermal imaging system. These values might serve for verification of the respective CFD model of combustion equipment.

  9. Distributed parameter modeling and thermal analysis of a spiral water wall in a supercritical boiler

    Directory of Open Access Journals (Sweden)

    Zheng Shu

    2013-01-01

    Full Text Available In this paper, a distributed parameter model for the evaporation system of a supercritical spiral water wall boiler is developed based on a 3-D temperature field. The mathematical method is formulated for predicting the heat flux and the metal-surface temperature. The results show that the influence of the heat flux distribution is more obvious than that of the heat transfer coefficient distribution in the spiral water wall tube, and the peak of the heat transfer coefficient decreases with an increment of supercritical pressure. This distributed parameter model can be used for a 600 MW supercritical-pressure power plant.

  10. Analog-experiment analysis of ash-deposition monitoring model of boiler economizers in power plants

    Institute of Scientific and Technical Information of China (English)

    CHENG Wei-liang; XIA Guo-dong; XU Shou-chen

    2005-01-01

    Ash deposition is a form of particulate fouling, and appears usually in boiler economizers. The ash deposition increases capital expenditure, energy input and maintenance costs. An analog experiment for monitoring ash deposition was performed from the analogous objective of a 410 t/h boiler economizer to verify the rationality and reliability of the ash-deposition-monitoring model presented in order to increase the security and economy in economizer running. The analog experiment platform is a tube-shell exchanger that conforms well to the conditions of a self-modeling area. The analog flue gas in the shell side is the heated air mixed with ash,and in the tube side the fluid is water heated by the flue gas. The fluid state in the water side and the flue gas side follows the second self-modeling area. A 4-factor-3 level orthogonal table was used to schedule 9 operation conditions of orthogonal experiment, with the 4 factors being heat power, flue gas velocity, ashes grain diameter and adding ashes quantity while the three levels are different values due to different position classes in every factor. The ash deposition thermal resistances is calculated by the model with the measure parameters of temperature and pressure drop. It shows that the values of the ash deposition thermal resistances gradually increase up to a stable state. And the experimental results are reliable by F testing method at α = 0. 001. Therefore, the model can be applied in online monitoring of ash deposition in a boiler economizers in power plants and provides scientific decision on ash deposition prediction and sootblowing.

  11. Black liquor combustion validated recovery boiler modeling: Final year report. Volume 3 (Appendices II, sections 2--3 and III)

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-08-01

    This project was initiated in October 1990, with the objective of developing and validating 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 key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 3 contains the following appendix sections: Formation and destruction of nitrogen oxides in recovery boilers; Sintering and densification of recovery boiler deposits laboratory data and a rate model; and Experimental data on rates of particulate formation during char bed burning.

  12. BPACK -- A computer model package for boiler reburning/co-firing performance evaluations. User`s manual, Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Wu, K.T.; Li, B.; Payne, R.

    1992-06-01

    This manual presents and describes a package of computer models uniquely developed for boiler thermal performance and emissions evaluations by the Energy and Environmental Research Corporation. The model package permits boiler heat transfer, fuels combustion, and pollutant emissions predictions related to a number of practical boiler operations such as fuel-switching, fuels co-firing, and reburning NO{sub x} reductions. The models are adaptable to most boiler/combustor designs and can handle burner fuels in solid, liquid, gaseous, and slurried forms. The models are also capable of performing predictions for combustion applications involving gaseous-fuel reburning, and co-firing of solid/gas, liquid/gas, gas/gas, slurry/gas fuels. The model package is conveniently named as BPACK (Boiler Package) and consists of six computer codes, of which three of them are main computational codes and the other three are input codes. The three main codes are: (a) a two-dimensional furnace heat-transfer and combustion code: (b) a detailed chemical-kinetics code; and (c) a boiler convective passage code. This user`s manual presents the computer model package in two volumes. Volume 1 describes in detail a number of topics which are of general users` interest, including the physical and chemical basis of the models, a complete description of the model applicability, options, input/output, and the default inputs. Volume 2 contains a detailed record of the worked examples to assist users in applying the models, and to illustrate the versatility of the codes.

  13. 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,...

  14. The simulation of start-up of natural circulation boiler based on the Astrom-Bell model

    Science.gov (United States)

    Zhang, Tianyu; Zhao, Zhenning; Li, Yuanyuan; Zhu, Xianran

    2017-01-01

    This paper presents a numerical investigation on the dynamic analysis of steam and water system of the natural circulation boiler SHL35.2.5/AI with the software MATLAB/SIMULINK. Based on the four-order Astrom-Bell model, a model applicable the specific boiler was established, casting light on the changes in parameters of designed, cold start and varying load condition. And a curve of cold start is obtained, which can be taken as reference for practical operation. In addition, in the condition of varying load, our model captured the phenomenon of false water level, and according analysis is made. Our study introduces a feasible method of simulation on the dynamic analysis of steam and water system on other boilers as well.

  15. Optimization of Load Assignment to Boilers in Industrial Boiler Plants

    Institute of Scientific and Technical Information of China (English)

    CAO Jia-cong; QIU Guang; CAO Shuang-hua; LIU Feng-qiang

    2004-01-01

    Along with the increasing importance of sustainable energy, the optimization of load assignment to boilers in an industrial boiler plant becomes one of the major projects for the optimal operation of boiler plants. Optimal load assignment for power systems has been a long-lasting subject, while it is quite new for industrial boiler plants. The existing methods of optimal load assignment for boiler plants are explained and analyzed briefly in the paper. They all need the fuel cost curves of boilers. Thanks to some special features of the curves for industrial boilers, a new model referred to as minimized departure model (MDM) of optimization of load assignment for boiler plants is developed and proposed in the paper. It merely relies upon the accessible data of two typical working conditions to build the model, viz. the working conditions with the highest efficiency of a boiler and with no-load. Explanation of the algorithm of computer program is given, and effort is made so as to determine in advance how many and which boilers are going to work. Comparison between the results using MDM and the results reported in references is carried out, which proves that MDM is preferable and practicable.

  16. Modelling of pulverized coal boilers: review and validation of on-line simulation techniques

    Energy Technology Data Exchange (ETDEWEB)

    Diez, L.I.; Cortes, C.; Campo, A. [University of Zaragoza, Zaragoza (Spain). Centro de Investigacion de Recursos y Consumos Energeticos (CIRCE)

    2005-07-01

    Thermal modelling of large pulverized fuel utility boilers has reached a very remarkable development, through the application of CFD techniques and other advanced mathematical methods. However, due to the computational requirements, on-line monitoring and simulation tools still rely on lumped models and semiempirical approaches, which are often strongly simplified and not well connected with sound theoretical basis. This paper reviews on-line modelling techniques, aiming at the improvement of their capabilities, by means of the revision and modification of conventional lumped models and the integration of off-line CFD predictions. The paper illustrates the coherence of monitoring calculations as well as the validation of the on-line thermal simulator, starting from real operation data from a case-study unit. The outcome is that it is possible to significantly improve the accuracy of on-line calculations provided by conventional models, taking into account the singularities of large combustion systems and coupling offline CFD predictions for selected scenarios.

  17. Thermal-hydraulic modeling of the steady-state operating conditions of a fire-tube boiler

    Directory of Open Access Journals (Sweden)

    Rahmani Ahmed

    2009-01-01

    Full Text Available In this work, we are interested to simulate the thermal-hydraulic behavior of three-pass type fire-tube boiler. The plant is designed to produce 4.5 tons per hour of saturated steam at 8 bar destined principally for heating applications. A calculation program is developed in order to simulate the boiler operation under several steady-state operating conditions. This program is based upon heat transfer laws between hot gases and the fire-tube internal walls. In the boiler combustion chamber, the heat transfer has been simulated using the well-stirred furnace model. In the convection section, heat balance has been carried out to estimate the heat exchanges between the hot gases and the tube banks. The obtained results are compared to the steady-state operating data of the considered plant. A comparative analysis shows that the calculation results are in good agreement with the boiler operating data. Furthermore, a sensitivity study has been carried out to assess the effects of input parameters, namely the fuel flow rate, air excess, ambient temperature, and operating pressure, upon the boiler thermal performances.

  18. Hybrid model predictive control applied to switching control of burner load for a compact marine boiler design

    DEFF Research Database (Denmark)

    Solberg, Brian; Andersen, Palle; Maciejowski, Jan

    2008-01-01

    This paper discusses the application of hybrid model predictive control to control switching between different burner modes in a novel compact marine boiler design. A further purpose of the present work is to point out problems with finite horizon model predictive control applied to systems for w...

  19. CFD modeling of small biomass-fired boilers, second stage; CFD-modellering av mindre biobraenslepannor, etapp 2

    Energy Technology Data Exchange (ETDEWEB)

    Loennermark, A. [Swedish National Testing and Research Inst., Boraas (Sweden); Leckner, B. [Chalmers Univ. of Techn., Goeteborg (Sweden). Dept. of Energy Technology

    2001-11-01

    The purpose of the project is to study how the design of the gas combustion chamber in a small boiler for biomass affects the emissions and how computer simulations can be used to decrease harmful emissions. The aim of the first part of the project was to investigate how phenomena and processes, important for the combustion, depend on various parameters. Within the frame of that part the temperature distribution, the flow pattern and the mixing processes have been studied. In the second part the combustion and the different reactions have been studied. A number of well-equipped combustion experiments in a small biomass-fired boiler have also been conducted to obtain better information about the boundary conditions. The results have been used to verify the simulations. The gas combustion chamber of a modern boiler using down draught firing has been simulated by using two Computational Fluid Dynamics codes, SOFIE and FLUENT. The results from the simulations show that with literature values for the reaction parameters, the reaction rates are controlled by mixing. This means that the reactions are fast and all the CO and the hydrocarbons were consumed. By varying the activation energy, it is possible to reach data that are more comparable with experimental data. The effects of the bowl in the gas combustion chamber on the combustion and mixing are discussed. The effects of the temperature and the radiation are also presented.

  20. Three Dimensional Modeling of Pulverized Coal combustion in a 600MW Corner Fired Boiler

    Institute of Scientific and Technical Information of China (English)

    SandroDal-Secco

    2000-01-01

    The three-dimensional code ESTET developed at the LNH has been used to predict the reactive flow in a 600 W coal fired boiler,Assuming a no-slip condition between the gas and the coal,the equations for a gas-particle mixture can e written.The pulverized coal particle size distribution is represented by a discrete number of particle size groups determined by the measured fineness distrbution.The combustion models taking into account the pyrolysis of the particle and the heterogeneous combustion of char have been validated using intensive measurements performed on the 600MW utility boiler.Heat fluxes were measured along the walls of the furnace and satisfactory agreement between computation and measurements has been achieved in terms of maximum flux location and heat flux intensity.Local measurements of velocities using LDV probe.gas temperature and gas species concentrations were performed in the vicinity of one burner and compared with the computed variables.Again we have observed a good agreement between the computations and the measurements in terms of jet penetration,temperature distribution.oxygen concentration and ash content.

  1. Efficiency of Small Scale Manually Fed Boilers —Mathematical Models

    OpenAIRE

    Lazar Savin; Milan Tomic; Ondrej Ponjican; Nebojsa Dedovic; Snezana Matic-Kekic; Todor Janic; Sasa Igic

    2012-01-01

    This study reviews test results for a biomass-fired hot water boiler with a nominal boiler thermal power of 120 kW. In the experiments, prismatic wheat straw bales were used as biomass. The impact of the quantity (220, 290, 360 and 430 m3 h−1) of inlet air fed to the boiler firebox was continuously monitored. This was to examine the influence of the quantity of inlet air and recirculation (0, 16.5 and 33%) of combustion products on the boiler ther...

  2. Advanced process control for solid fuel boilers. Phase 2; Avancerad processtyrning av fastbraensleeldade rostpannor. Etapp 2

    Energy Technology Data Exchange (ETDEWEB)

    Ehleskog, Rickard; Lundborg, Rickard; Schuster, Robert; Wrangensten, Lars [AaF-Energikonsult AB, Stockholm (Sweden)

    2002-04-01

    AaF-Energikonsult AB runs within the research programme 'Applied combustion technology' a bigger project under the title 'Possibilities to improved operation of forest-industrial bark boilers by optimised combustion control'. In the project several measures have been identified, that can help to improve the conditions favourable for the combustion and fluid dynamic, for four selected reference grate boilers and grate boilers in general. The boiler at Billerud's paper mill, which is underlying to this project in several ways, is now being rebuilt. During the modifications of the boiler the existing control system will be modified with modern technique to enable operation with low emissions. The new control system consists of several parts, of witch the IR-based ones for fuel input and grate feeding are two totally separated systems. The pressure of the dome, i.e. the effect of the boiler, is the most superior parameter, and is regulated with the combustion air. Amounts of secondary and tertiary air are quoted to the total combustion airflow. The primary oxygen level is primarily regulated with the tertiary air. But if this won't be done without the tertiary air to diverge from de defined working area, the secondary air will assist. The oxygen set point is constantly decreasing until the CO-level exceeds a defined level. Then, the set point will be momentary increased. CFD-calculations have been performed for the modified boiler in Karlsborg for two different loads. The simulations clearly show that the flue gases have a more even retention time in the modified boiler and that the flow pattern is significantly improved. However, concentration gradients of oxygen and temperature gradients still exist. The conclusion is that there is a potential for further improving of the air and flue gas control strategies. The following new control strategies are proposed in the project based on conventional analyse technology; If the furnace

  3. Black liquor combustion validated recovery boiler modeling: Final year report. Volume 2 (Appendices I, section 5 and II, section 1)

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-08-01

    This project was initiated in October 1990, with the objective of developing and validating 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 key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 2 contains the last section of Appendix I, Radiative heat transfer in kraft recovery boilers, and the first section of Appendix II, The effect of temperature and residence time on the distribution of carbon, sulfur, and nitrogen between gaseous and condensed phase products from low temperature pyrolysis of kraft black liquor.

  4. Using scaled physical model for assessment of mechanical damping of power plant boiler structure

    Directory of Open Access Journals (Sweden)

    Jiří Protivínský

    2016-03-01

    Full Text Available To determine dynamic response of mechanical system is always a complex issue. One of the core inputs for such a task is a coefficient of logarithmic damping decrement. There is no way how to determine this coefficient analytically; it needs to be measured on the final product. There has been a large amount of dynamic tests carried out on common structures and the results have been incorporated in design codes. Nevertheless, power plant boiler structure differs significantly from common structures. To provide a large number of dynamic tests on real facility is very difficult for many reasons. Using a scaled model is a way how to achieve relevant data based on repeatable experiment.

  5. Sootblowing optimization for improved boiler performance

    Science.gov (United States)

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

    2013-07-30

    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.

  6. Analysis Model for Unit Consumption of Power Boilers and its Application%电厂锅炉单耗分析模型及其应用

    Institute of Scientific and Technical Information of China (English)

    周少祥; 姜媛媛; 吴智泉; 杨晓伟; 胡三高; 徐鸿

    2012-01-01

    Based on the theory of unit consumption analysis and taking the heat loads of various boiler heat surfaces as different heat products, a complete unit consumption analysis model has been set up by studying following three irreversible thermodynamic processes and their additional unit consumption of fuel, such as from the fuel exergy to heat exergy in gas at theoretical combustion temperature, then to heat exergy in gas at actually exothermic temperature, and finally to heat exergy in heat products. The model has been applied to the unit consumption analysis for an ultra supercritical boiler on the basis of thermal calculation. Results show that among all the heat exchangers, the heat exergy obtained by working medium from boiler economizer is the least, and its exergy efficiency is accordingly the lowest, which proves boiler economizer to be most uneconomic, indicating that the boiler economizer actually restricts the improvement of generating efficiency of fossil fuel-fired power units.%根据单耗分析理论,将锅炉各受热面的工质吸热量视为不同的热产品,分析生产这些热产品所经过的从燃料到理论燃烧温度下的烟气热流,再到实际燃烧放热温度下的烟气热流,最后到热产品具有的工质热流共3个不可逆热力学过程及其附加燃料单耗,建立了一套完整的电厂锅炉单耗分析模型;并针对某超临界机组系统及其热力参数,在热力计算的基础上,进行了锅炉单耗分析.结果表明:工质在省煤器吸热获得热流是最小的,其效率最低;从理论上证明了锅炉省煤器的概念名不副实,它的存在成为燃煤火电机组发电效率进一步提高的制约因素.

  7. Presence and numbers of Campylobacter, Escherichia coli and Salmonella determined in boiler carcass rinses from United States processing plants in the hazard analysis and critical control point-based inspection models project

    Science.gov (United States)

    In 1999, the USDA-Food Safety Inspection Service introduced an inspection system called The HACCP-Based Inspection Models Project (HIMP). HIMP varies from traditional inspection in that more emphasis is placed on system inspection and verification. Each carcass is still visually inspected but some...

  8. 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.

  9. 锅炉斜炉底安装工艺%The Installation Process of Boiler's Inclined Furnace Bottom

    Institute of Scientific and Technical Information of China (English)

    朱丹萍

    2013-01-01

    Water wall ash hopper, commonly known as inclined furnace bottom,which is named by arranged in the bottom of the furnace and the front and rear walls form a certain angle with the horizontal plane. This article describes the inclined furnace bottom lifting in the boiler's heating surface components of different capacity units, depicts the time trajectory of continuous expansion for domestic unit capacity from one side, at the same time, this article illustrates that using new lifting process could accelerate the construction schedule, improve project quality and reduce the risk of the job, and provides a new concept for the installation of large boilers.%水冷壁灰斗,俗称斜炉底,因其布置于炉膛底部且前后墙与水平面成一定的夹角而得名。本文通过对不同容量机组锅炉受热面组件中斜炉底吊装的介绍,从一个侧面描绘国内机组容量不断的扩大的时间轨迹,同时说明了利用新的吊装工艺可以加快施工进度,提高工程质量,减少危险作业,为大型锅炉的安装提供了新的施工理念。

  10. CFD modeling of stripper ash cooler of circulating fluidized bed boiler

    Directory of Open Access Journals (Sweden)

    Ravi Inder Singh

    2016-09-01

    Full Text Available The stable operation of a bottom ash cooler is vital for the operation of the circulating fluidized bed boiler. To assess, the stability of the ash cooler, it is important to have a thorough understanding of the flow behaviour. Although, many experimental results been reported in literature, CFD modelling of the ash cooler has not been carried out. In this paper, the transient computational analysis of a novel stripper ash cooler has been carried out using the Eulerian–Eulerian multiphase approach. The phase coupled SIMPLE algorithm has been used to solve the multiphase equations and the Gidaspow drag model has been employed to model the interaction between the fluidized air and ash. Two cases have been analysed in this paper. In the first case, the filling of the ash in the cooler has been analysed and in the second case, the phenomenon of fluidized bed bubbling in the ash cooler has been simulated. The study the of flow characteristics of hot ash has been studied. The contours of temperature, phase volume and bubbling have been analyzed in this paper.

  11. Steam boilers: process models for improved operation and design

    NARCIS (Netherlands)

    Ahnert, F.

    2007-01-01

    Biomass combustion can be an economic way to contribute to the reduction of CO2 emissions, which are a main suspect of the so-called greenhouse effect. In order to promote a widespread utilization of biomass combustion, operational problems like fuel treatment, slagging, fouling and corrosion have

  12. Steam boilers: process models for improved operation and design

    NARCIS (Netherlands)

    Ahnert, F.

    2007-01-01

    Biomass combustion can be an economic way to contribute to the reduction of CO2 emissions, which are a main suspect of the so-called greenhouse effect. In order to promote a widespread utilization of biomass combustion, operational problems like fuel treatment, slagging, fouling and corrosion have t

  13. Nonlinear predictive control of a boiler-turbine unit: A state-space approach with successive on-line model linearisation and quadratic optimisation.

    Science.gov (United States)

    Ławryńczuk, Maciej

    2017-03-01

    This paper details development of a Model Predictive Control (MPC) algorithm for a boiler-turbine unit, which is a nonlinear multiple-input multiple-output process. The control objective is to follow set-point changes imposed on two state (output) variables and to satisfy constraints imposed on three inputs and one output. In order to obtain a computationally efficient control scheme, the state-space model is successively linearised on-line for the current operating point and used for prediction. In consequence, the future control policy is easily calculated from a quadratic optimisation problem. For state estimation the extended Kalman filter is used. It is demonstrated that the MPC strategy based on constant linear models does not work satisfactorily for the boiler-turbine unit whereas the discussed algorithm with on-line successive model linearisation gives practically the same trajectories as the truly nonlinear MPC controller with nonlinear optimisation repeated at each sampling instant. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  14. A Cold Model Aerodynamical Test of Air-Staged Combustion in a Tangential Firing Utility Boiler

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hui-juan; HUI Shi-en; ZHOU Qu-lan

    2007-01-01

    The purpose of this paper is to present the flow field in the 300MW tangential firing utility boiler that used the Low NOx Concentric Firing System (LNCFS). Using the method of cold isothermal simulation ensures the geometric and boundary condition similarity. At the same time the condition of self-modeling is met. The experimental results show that the mixture of primary air and secondary air becomes slower, the average turbulence magnitude of the main combustion zone becomes less and the relative diameter of the tangential firing enlarges when the secondary air deflection angle increases. When the velocity pressure ratio of the secondary air to the primary air (p2/p1) enlarges, the mixture of the secondary air and the primary air becomes stronger, the average turbulence magnitude of the main combustion zone increases, and the relative diameter of the tangential firing becomes larger. Because the over fire air (OFA) laid out near the wall has a powerful penetration, the relative diameter of the tangential firing on the section of the OFA is very little, but the average turbulence magnitude is great. When the velocity pressure ratio of the OFA to the primary air pOFA/p1 increases, the relative diameter of the tangential firing on the section of the OFA grows little, the average turbulence magnitude becomes larger and the penetration of the OFA becomes more powerful.

  15. Numerical Modeling of the Effect of Thawing of Soil in the Area of Placing Tanks for Storage Fuel of Thermal Power Plants and Boiler

    Directory of Open Access Journals (Sweden)

    Polovnikov V.Yu.

    2016-01-01

    Full Text Available This paper describes the numerical modeling of heat transfer in the area placing of the tank for storage fuel of thermal power plant and boiler with considering the influence of thawing of the soil. We have established that the thawing of the soil in the area of placing of the tank for storage fuel of thermal power plant and boiler have little effect on the change of heat loss.

  16. Thermal Analysis of Superheater Platen Tubesin Boilers

    Directory of Open Access Journals (Sweden)

    Shahram Falahatkar

    2014-01-01

    Full Text Available Superheaters are among the most important components of boilers and have major importance due to this operation in high temperatures and pressures. Turbines are sensitive to the fluctuation of superheaterstemperature;therefore even the slightest fluctuation in the outlet vapor temperature from the superheaters does damage the turbine axis and fins. Examining the potential damages of combustion in the boilers and components such as the superheaters can have a vital contribution to the progression of the productivity of boiler, turbine and the power plant altogether it solutions are to be fund to improve such systems. In this study, the focus is on the nearest tube set of superheaters to the combustion chamber.These types of tubes are exposed to a wide range ofcombustion flames such that the most heat transfer to them is radiation type.Here, the 320 MW boiler of Isfahan power plant (Iran, the combustion chamber, 16 burners and the platensuperheater tubes were remodeled by CFD technique. The fluid motion, the heat transfer and combustion processes are analyzed. The two-equation turbulence model of k-εis adopted to measure the eddy viscosity. The eddy dissipation model is used to calculate the combustion as well as the P-1 radiation model to quantify the radiation. The overheated zones of superheater tubes and the combustion chamber are identified in order toimprove this problem by applying the radiation thermal shields and knees with porous crust which are introduced as the new techniques.

  17. Modeling N2O Reduction and Decomposition in a Circulating Fluidized bed Boiler

    DEFF Research Database (Denmark)

    Johnsson, Jan Erik; Åmand, Lars-Erik; Dam-Johansen, Kim;

    1996-01-01

    The N2O concentration was measured in a circulating fluidized bed boiler of commercial size. Kinetics for N2O reduction by char and catalytic reduction and decomposition over bed material from the combustor were determined in a laboratory fixed bed reactor. The destruction rate of N2O in the comb......The N2O concentration was measured in a circulating fluidized bed boiler of commercial size. Kinetics for N2O reduction by char and catalytic reduction and decomposition over bed material from the combustor were determined in a laboratory fixed bed reactor. The destruction rate of N2O...

  18. Black liquor combustion validated recovery boiler modeling: Final year report. Volume 1 (Main text and Appendix I, sections 1--4)

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-08-01

    This project was initiated in October 1990, with the objective of developing and validating 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 key tasks to be accomplished were as follows: (1) Complete the development of enhanced furnace models that have the capability to accurately predict carryover, emissions behavior, dust concentrations, gas temperatures, and wall heat fluxes. (2) Validate the enhanced furnace models, so that users can have confidence in the predicted results. (3) Obtain fundamental information on aerosol formation, deposition, and hardening so as to develop the knowledge base needed to relate furnace model outputs to plugging and fouling in the convective sections of the boiler. (4) Facilitate the transfer of codes, black liquid submodels, and fundamental knowledge to the US kraft pulp industry. Volume 1 contains the main body of the report and the first 4 sections of Appendix 1: Modeling of black liquor recovery boilers -- summary report; Flow and heat transfer modeling in the upper furnace of a kraft recovery boiler; Numerical simulation of black liquor combustion; and Investigation of turbulence models and prediction of swirling flows for kraft recovery furnaces.

  19. Numerical investigation of full scale coal combustion model of tangentially fired boiler with the effect of mill ducting

    Energy Technology Data Exchange (ETDEWEB)

    Achim, Daniela [Monash University, Department of Chemical Engineering, Clayton, VIC (Australia); Naser, J.; Morsi, Y.S. [Swinburne University of Technology, Faculty of Engineering and Industrial Sciences, Hawthorn, VIC (Australia); Pascoe, S. [Yallourn Energy, Moe, VIC (Australia)

    2009-11-15

    In this paper a full scale combustion model incorporating upstream mill ducting of a large tangentially fired boiler with flue gas recirculation was examined numerically. Lagrangian particle tracking was used to determine the coal particle paths and the Eddy Dissipation Model for the analysis of the gas phase combustion. Moreover volatiles and gaseous char products, given off by the coal particles were modelled by Arrhenius single phase reactions and a transport equation was solved for each material given off by the particles. Thermal, prompt, fuel and reburn NO{sub x} models with presumed probability density functions were used to model NO{sub x} production and the discrete transfer radiation model was used to model radiation heat transfer. Generally, the findings indicated reasonable agreement with observed qualitative and quantitative data of incident heat flux on the walls. The model developed here could be used for a range of applications in furnace design and optimisation of gas emissions of coal fired boiler plants. (orig.)

  20. Further development of recovery boiler; Soodakattilan kehitystyoe

    Energy Technology Data Exchange (ETDEWEB)

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

    1996-12-01

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

  1. CFD analysis of the pulverized coal combustion processes in a 160 MWe tangentially-fired-boiler of a thermal power plant

    OpenAIRE

    Silva,Cristiano V. da; Indrusiak,Maria Luiza S; Beskow,Arthur B

    2010-01-01

    The strategic role of energy and the current concern with greenhouse effects, energetic and exergetic efficiency of fossil fuel combustion greatly enhance the importance of the studies of complex physical and chemical processes occurring inside boilers of thermalpower plants. The state of the art in computational fluid dynamics and the availability of commercial codes encourage numeric studies of the combustion processes. In the presentwork the commercial software CFX © Ansys Europe Ltd. was ...

  2. Plasma-supported coal combustion in boiler furnace

    Energy Technology Data Exchange (ETDEWEB)

    Askarova, A.S.; Karpenko, E.I.; Lavrishcheva, Y.I.; Messerle, V.E.; Ustimenko, A.B. [Kazakh National University, Alma Ata (Kazakhstan). Dept. of Physics

    2007-12-15

    Plasma activation promotes more effective and environmentally friendly low-rank coal combustion. This paper presents Plasma Fuel Systems that increase the burning efficiency of coal. The systems were tested for fuel oil-free start-up of coal-fired boilers and stabilization of a pulverized-coal flame in power-generating boilers equipped with different types of burners, and burning all types of power-generating coal. Also, numerical modeling results of a plasma thermochemical preparation of pulverized coal for ignition and combustion in the furnace of a utility boiler are discussed in this paper. Two kinetic mathematical models were used in the investigation of the processes of air/fuel mixture plasma activation: ignition and combustion. A I-D kinetic code PLASMA-COAL calculates the concentrations of species, temperatures, and velocities of the treated coal/air mixture in a burner incorporating a plasma source. The I-D simulation results are initial data for the 3-D-modeling of power boiler furnaces by the code FLOREAN. A comprehensive image of plasma-activated coal combustion processes in a furnace of a pulverized-coal-fired boiler was obtained. The advantages of the plasma technology are clearly demonstrated.

  3. Contribution to the development of the simulation model for the rotary cap burner in the marine steam boiler

    Directory of Open Access Journals (Sweden)

    Dvornik Joško

    2015-01-01

    Full Text Available This paper presents the simulation model for determining the intervals of preventive replacement of the system's components. The application of the Weibull distribution has been proved to be efficient in the approximation of many forms of delay, while numerical integration supported by Simpson formula and Fortran software has been applied to simulate optimum values of the preventive replacement of the components of the rotary cap burner SAACKE, type SKV 60 in the marine steam boiler, on the basis of the available data gathered through the system's exploitation and through empirical assumptions.

  4. Numerical investigation of a straw combustion boiler – Part I: Modelling of the thermo-chemical conversion of straw

    Directory of Open Access Journals (Sweden)

    Dernbecher Andrea

    2016-01-01

    Full Text Available In the framework of a European project, a straw combustion boiler in conjunction with an organic Rankine cycle is developed. One objective of the project is the enhancement of the combustion chamber by numerical methods. A comprehensive simulation of the combustion chamber is prepared, which contains the necessary submodels for the thermo-chemical conversion of straw and for the homogeneous gas phase reactions. Part I introduces the modelling approach for the thermal decomposition of the biomass inside the fuel bed, whereas part II deals with the simulation of the gas phase reactions in the freeboard.

  5. Design of Process System for Heat-conducting Oil Boiler House%浅析港区导热油锅炉房工艺系统设计

    Institute of Scientific and Technical Information of China (English)

    韩刚; 杨平; 张自强

    2013-01-01

    In general, a port require a large amount of low-pressure high-temperature heat source,meanwhile,lots of heat-supply points are spread around the region. However,new large-scale coal-fired boiler has to be restricted as per harbor's air pollutant release standard, and the heat-supply pipeline results in a large sum of energy transportation consumption. In comparison with coal-fired boiler, heat-conducting oil boiler meets the requirement of energy-saving and emission reduction well and agrees with harbor's heat-supply characteristic. Some projects are taken as examples to introduce the design idea on liquid-gas circulating process system of heat-conducting oil boiler house, discuss the selection of heat-conducting medium, supporting equipment and accessories as well as key technical issues on heating ventilation design of boiler house.%一般港口对低压高温热源的需求量大、供热用户点多且较分散,新建大型燃煤锅炉不仅要受港区大气污染物排放总量的限制,供热管网的输送能耗也很大,相比之下导热油锅炉更符合国家节能减排的要求和港区供热的特点。结合工程实例详细介绍导热油锅炉房液体与气体循环工艺系统的设计思路,论述导热介质、配套设备和附件的选用,以及锅炉房的暖通设计等关键技术问题。

  6. Digest of "Invariant Method of Load Independent Pressure Control in Steam Boiler"

    OpenAIRE

    Sniders, Andris; Komass, Toms

    2012-01-01

    The paper considers the possibility of steam production and supply process improvement by perfection of the steam boiler control system, applying invariance principle that makes possible preemptive compensation of the influence of steam expenditure as a disturbance on the control process quality and efficiency. For the development of invariant control system, the mathematical modeling and simulation in MATLAB - SIMULINK environment is made. The control unit is low pressure steam boiler with o...

  7. Modeling on the Combustion System of Large-Scale Circulating Fluidized Bed Boiler%大型循环流化床锅炉燃烧系统数学模拟

    Institute of Scientific and Technical Information of China (English)

    徐志; 王勤辉; 骆仲泱; 倪明江

    2011-01-01

    数学模型是研究和发展大型循环流化床锅炉的重要方法.在浙江大学提出的适用于中小型循环流化床锅炉的整体数学模型的基础上,建立了适用于大型循环流化床锅炉的数学模型.模型采用了基于环-核结构的流体动力学模型,并考虑了宽筛分燃料颗粒所经历的破碎、燃烧等过程.模拟了国内一台300MWe循环流化床锅炉,模拟计算结果与锅炉的运行测量值基本吻合.%Mathematical model is an important method in the study and the development of large-scale circulating fluidized bed (CFB) boiler. On the basis of the overall mathematical model for the medium and small scale CFB boiler, a mathematical model for large-scale CFB boiler is developed. In the modeling, the CFB riser is divided in two regions: the bottom zone in turbulent fluidization regime and the upper zone with core-annulus solids flow structure. The model takes into account the fragmentation and combustion process of the widely sized particles. The model results are in good agreement with the operational data of a 300 MWe CFB boiler.

  8. 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)

  9. Development of a Novel Oxygen Supply Process and its Integration with an Oxy-Fuel Coal-Fired Boiler

    Energy Technology Data Exchange (ETDEWEB)

    None

    2006-12-31

    BOC, the world's second largest industrial gas company, has developed a novel high temperature sorption based technology referred to as CAR (Cyclic Autothermal Recovery) for oxygen production and supply to oxy-fuel boilers with flue gas recycle. This technology is based on sorption and storage of oxygen in a fixed bed containing mixed ionic and electronic conductor materials. The objective of the proposed work was to construct a CAR PDU that was capable of producing 10-scfm of oxygen, using steam or recycled flue gas as the sweep gas, and install it in the Combustion Test Facility. The unit was designed and fabricated at BOC/The Linde Group, Murray Hill, New Jersey. The unit was then shipped to WRI where the site had been prepared for the unit by installation of air, carbon dioxide, natural gas, nitrogen, computer, electrical and infrastructure systems. Initial experiments with the PDU consisted of flowing air into both sides of the absorption systems and using the air heaters to ramp up the bed temperatures. The two beds were tested individually to operational temperatures up to 900 C in air. The cycling process was tested where gases are flowed alternatively from the top then bottom of the beds. The PDU unit behaved properly with respect to flow, pressure and heat during tests. The PDU was advanced to the point where oxygen production testing could begin and integration to the combustion test facility could occur.

  10. Mixing of a reburn fuel in a cold model of a front-wall coal-fired boiler

    Energy Technology Data Exchange (ETDEWEB)

    Verlaan, A.L.; Dugue, J.; Weber, R. [International Flame Research Foundation, IJmuiden (Netherlands)

    1998-12-31

    An experimental research program has been carried out in order to determine the optimum reburn injection methods for pulverised coal fired boilers. Funding of this program was provided by the IFRF Members and the European Union (JOULE II extension, Project nr. 1B). The study is specifically concerned with the optimisation of natural gas reburning in front wall, pulverised coal fired boilers. The technical objectives are: to provide guidelines for optimising the reburn natural gas injection methods; to generate a set of simple empirical equations describing the trajectory, penetration distance and mixing time scales for practical nozzles; and to provide detailed experimental data that can be used to validate mathematical modelling computations. Using Laser Doppler Velocimetry the velocity profiles in the model are measured. The mixing characterisation is performed using Laser Sheet Visualisation, which creates images showing particle density over a plane of measurement. From these images properties are calculated such as: average intensity, RMS-intensity, intermittency, dissipation, unmixedness and spatial correlation. With this data simple relations are derived, describing jet penetration and mixing. 18 refs., 16 figs., 10 tabs.

  11. CFD Simulation On CFBC Boiler

    Directory of Open Access Journals (Sweden)

    Amol S. Kinkar

    2015-02-01

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

  12. Boiler level control system based on ControlLogix5550 PLC

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>This paper is a research design based on EFPT process control device.In the design,actual industry field has been simulated and corresponding modelling has been carried on for the boiler level system.Then the appropriate PID parameter has been sorted out and ControlLogix5550 PLC has been used to control the entire boiler level system. At last,a corresponding control interface has been established and the boiler level has been under a safe and accurate control.

  13. Long-term operational experiences in the preparation of river Elbe water to boiler feedwater with membrane processes; Langzeitbetriebserfahrungen bei der Aufbereitung von Elbewasser zu Kesselspeisewasser mit Membranverfahren

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Juergen [OSMO Membrane Systems GmbH, Korntal-Muenchingen (Germany); Batram, Juergen; Portner, Ronny [Aurubis AG, Hamburg (Germany)

    2013-09-01

    In Hamburg/Germany, the Aurubis AG (formerly Norddeutsche Affinerie) operates an industrial power plant to generate electricity and steam. For the past ten years, the annual demand of boiler feedwater (350,000 m{sup 3}) has been obtained with an economical water treatment plant based on membrane processes directly from the river Elbe. The water treatment plant called NAqua built uses roughly pre-filtered river water. The produced water quality corresponds to the requirements of the current VGB-Standard 450 'Feedwater, Boiler Water and Steam Quality for Power Plants/Industrial Plants'. Since August 2002, the water treatment plant has been successfully in operation, and based on the described technique it belongs to the least recently operating plants in Germany. (orig.)

  14. Model Research of Gas Emissions From Lignite and Biomass Co-Combustion in a Large Scale CFB Boiler

    Directory of Open Access Journals (Sweden)

    Krzywański Jarosław

    2014-06-01

    Full Text Available The paper is focused on the idea of a combustion modelling of a large-scale circulating fluidised bed boiler (CFB during coal and biomass co-combustion. Numerical computation results for three solid biomass fuels co-combustion with lignite are presented in the paper. The results of the calculation showed that in previously established kinetics equations for coal combustion, some reactions had to be modified as the combustion conditions changed with the fuel blend composition. Obtained CO2, CO, SO2 and NOx emissions are located in borders of ± 20% in the relationship to the experimental data. Experimental data was obtained for forest biomass, sunflower husk, willow and lignite cocombustion tests carried out on the atmospheric 261 MWe COMPACT CFB boiler operated in PGE Turow Power Station in Poland. The energy fraction of biomass in fuel blend was: 7%wt, 10%wt and 15%wt. The measured emissions of CO, SO2 and NOx (i.e. NO + NO2 were also shown in the paper. For all types of biomass added to the fuel blends the emission of the gaseous pollutants was lower than that for coal combustion.

  15. Modeling N2O Reduction and Decomposition in a Circulating Fluidized bed Boiler

    DEFF Research Database (Denmark)

    Johnsson, Jan Erik; Åmand, Lars-Erik; Dam-Johansen, Kim

    1996-01-01

    in the combustion chamber and the cyclone was calculated taking three mechanisms into account: Reduction by char, catalytic decomposition over bed material and thermal decomposition. The calculated destruction rate was in good agreement with the measured destruction of N2O injected at different levels in the boiler...... decomposition over bed material, and homogeneous thermal decomposition was negligible. However, at higher levels in the combustor the solids concentration is lower: at the top 60% of the N2O destruction was due to thermal decomposition and in the cyclone heterogeneous destruction of N2O was insignificant...

  16. Characterizing and modeling of an 88 MW grate-fired boiler burning wheat straw: Experience and lessons

    DEFF Research Database (Denmark)

    Yin, Chungen; Rosendahl, Lasse Aistrup; Clausen, Sønnik

    2012-01-01

    an acceptable agreement. The discrepancies are analyzed from different aspects. The lessons learned and experience gained from this and other case studies are summarized and discussed in detail, which can facilitate the modeling validation effort as well as improve grate-firing technology. Some of the addressed......Grate-firing is one of the main technologies currently used for biomass combustion for heat and power production. However, grate-firing is yet to be further developed, towards a better technology for biomass combustion, particularly towards higher efficiency, lower emissions, and better reliability...... and availability. To better understand grate-firing of biomass and to establish a reliable but relatively simple Computational Fluid Dynamics (CFD) modeling methodology for industrial applications, biomass combustion in a number of different grate boilers has been measured and modeled. As one of the case studies...

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

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Ming [Purdue University, West Lafayette, IN; Abdelaziz, Omar [ORNL; Yin, Hongxi [Southeast University, Nanjing, China

    2014-11-01

    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 gas boilers for applications with process fluid return temperatures higher than or close to the dew point of the water vapor in the flue gas.

  18. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Tice, D.R.; Platts, N.; Raffel, A.S. [Serco Assurance (United Kingdom); Rudge, A. [British Energy Generation Ltd. (United Kingdom)

    2002-07-01

    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

  20. Investigations of operation problems at a 200 MWe PF boiler

    Directory of Open Access Journals (Sweden)

    Peta Sandile

    2015-09-01

    Full Text Available To minimize oxides of nitrogen (NOx emission, maximize boiler combustion efficiency, achieve safe and reliable burner combustion, it is crucial to master global boiler and at-the-burner control of fuel and air flows. Non-uniform pulverized fuel (PF and air flows to burners reduce flame stability and pose risk to boiler safety by risk of reverse flue gas and fuel flow into burners. This paper presents integrated techniques implemented at pilot ESKOM power plants for the determination of global boiler air/flue gas distribution, wind-box air distribution and measures for making uniform the flow being delivered to burners within a wind-box system. This is achieved by Process Flow Modelling, at-the-burner static pressure measurements and CFD characterization. Global boiler mass and energy balances combined with validated site measurements are used in an integrated approach to calculate the total (stoichiometric + excess air mass flow rate required to burn the coal quality being fired, determine the actual quantity of air that flows through the burners and the furnace ingress air. CFD analysis and use of at-the-burner static, total pressure and temperature measurements are utilized in a 2-pronged approach to determine root-causes for burner fires and to evaluate secondary air distribution between burners.

  1. CFD modeling of ash deposition for co-combustion of MBM with coal in a tangentially fired utility boiler

    NARCIS (Netherlands)

    Taha, T.J.; Stam, A.F.; Stam, K.; Brem, G.

    2013-01-01

    Ash deposition is one of the main challenges that needs to be tackled in response to increased percentage of biomass co-firing in pulverized fuel boilers. In this study, a model has been developed to investigate the slagging behavior of meat and bone meal (MBM) at higher co-firing rates in the Maasv

  2. 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.

  3. The Study of Gas-Dynamic Processes in the Current Boiler Fluidized Bed

    Directory of Open Access Journals (Sweden)

    Baturin Dmitry A.

    2015-01-01

    Full Text Available The paper presents a numerical simulation of the furnace with a circulating fluidized bed. Numerical study carried out for the bottom of the combustion chamber with the varying heights of volume filling. The results of the concentration of particulate matter and fields of speeding, as well as a graphical representation of changes in the concentration of particles on the bed height. Simulation performed in Euler - Euler representation on a 2D model.

  4. The Study of Dynamic Processes in the Boiler Furnace with Circulating Fluidized Bed

    OpenAIRE

    Gil A. V.; Baturin D. A.

    2016-01-01

    The paper presents a numerical simulation of the furnace with a circulating fluidized bed. Numerical study carried out on all volume of the combustion chamber. The results contours of particulate matter concentration and of velocities, as well as a graphical representation of changes in the concentration of particles on the bed height are shown. Simulation performed in Eulerian - Eulerian and Lagrange representation on a 3D model.

  5. The Study of Dynamic Processes in the Boiler Furnace with Circulating Fluidized Bed

    Directory of Open Access Journals (Sweden)

    Gil A. V.

    2016-01-01

    Full Text Available The paper presents a numerical simulation of the furnace with a circulating fluidized bed. Numerical study carried out on all volume of the combustion chamber. The results contours of particulate matter concentration and of velocities, as well as a graphical representation of changes in the concentration of particles on the bed height are shown. Simulation performed in Eulerian - Eulerian and Lagrange representation on a 3D model.

  6. Computer simulation of the fire-tube boiler hydrodynamics

    OpenAIRE

    Khaustov Sergei A.; Zavorin Alexander S.; Buvakov Konstantin V.; Sheikin Vyacheslav A.

    2015-01-01

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

  7. 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.

  8. Oxy-Combustion Boiler Material Development

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-01-31

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

  9. Oxy-Combustion Boiler Material Development

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-01-31

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

  10. Computational Modeling of Tangentially Fired Boiler (I) Models, Flow Field and Temperature Profiles

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this work, an Eulerian/Lagrangian approach has been employed to investigate numerically the flow characteristics, heat transfer and combustion in a tangentially fired furnace. The RNG (Re-normalization group) k-e model and a new method for cell face velocity interpolation based on a non-staggered grid system are employed. To avoid pseudo-diffusion that is significant in modeling tangentially fired furnaces, attempts are made at improving the differential volume scheme. Some new developments on turbulent diffusion of particles are also taken into account. Thus, computational accuracy is improved substantially.

  11. 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.

  12. Optimised control of coal-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Owens, D.H.; MacConnell, P.F.A.; Neuffer, D.; Dando, R. [University of Exeter, Exeter (United Kingdom). Centre for System and Control Engineering

    1997-07-01

    The objective of the project is to develop and specify a control methodology that will enable existing coal combustion plant to take maximum advantage of modern control techniques. The research is specifically aimed at chain-grate stoker plant (such as the test facility at the Coal Research Establishment, Cheltenham) on which little work has been done for thirty years yet which still represents a large proportion of industrial coal-fired plant in operation worldwide. In detail, the project: reviewed existing control strategies for moving grate stokers, highlighting their limitations and areas for improvements; carried out plant trials to identify the system characteristics such as response time and input/output behaviour; developed a theoretical process based on physical and chemical laws and backed up by trial data; specified control strategies for a single boiler; simulated and evaluated the control strategies using model simulations; developed of an optimised. Control strategy for a single boiler; and assessed the applicability and effects of this control strategy on multiple boiler installations. 67 refs., 34 figs.

  13. Evaluation of Biomass and Coal Briquettes for a Spreader Stoker Boiler Using an Experimental Furnace --- Modeling and Test

    Science.gov (United States)

    Wiggins, Gavin Memminger

    The compliance of coal-fired boilers with emissions regulations is a concern for many facilities. The introduction of biomass briquettes in industrial boilers can help to reduce greenhouse gas emissions and coal usage. In this research project, a thermodynamic chemical equilibrium model was derived and analytical simulations performed for a coal boiler system for several types of biomass fuels such as beech, hickory, maple, poplar, white oak, willow, sawdust, torrefied willow, and switchgrass. The biomass emissions were compared to coal and charcoal emissions. The chemical equilibrium analysis numerically estimated the emissions of CO, CO2, NO, NO2, N 2O, SO2, and SO3. When examining the computer results, coal and charcoal emitted the highest CO, CO2, and SO x levels while the lowest (especially for SOx) were reached by the biomass fuels. Similarly, NOx levels were highest for the biomass and lowest for coal and charcoal. To validate these analytical results, a custom traveling grate furnace was designed and fabricated to evaluate different types of biofuels in the laboratory for operation temperatures and emissions. The furnace fuels tested included coal, charcoal, torrefied wood chips, and wood briquettes. As expected, the coal reached the highest temperature while the torrefied wood chips offered the lowest temperature. For CO and NO x emissions, the charcoal emitted the highest levels while the wood briquettes emitted the lowest levels. The highest SO2 emissions were reached by the coal while the lowest were emitted by the wood briquettes. When compared to the coal fuel, charcoal emissions for CO increased by 103%, NO and NOx decreased by 21% and 20% respectively, and SO2 levels decreased by 92%. For torrefied wood, emissions for CO increased by 17%, NO and NOx decreased by 58% and 57% respectively, and SO 2 decreased by 90%. For wood briquettes, emissions for CO decreased by 27%, NO and NOx decreased by 66%, and SO2 levels decreased by 97%. General trends in

  14. A Mathematical Model for Differential—Velocity Circulating Fluidized Bed Boiler

    Institute of Scientific and Technical Information of China (English)

    LiZhao; XiangdongXu

    1999-01-01

    The scheme of differential-velocity circulating fluidized bed was put forward by Thermal Engineering Department of Tsinghua university in 1992 and got patent simultaneously.An internal bed material circulation in combustor can be established by the discrepancy of entrainment at different air velocity,and separates the combustor into three different velocity regions,which constitutes the differential-velocity inside circulation.Mathematical modeling and simulation may facilitate understanding,Development and operation of this new process.Here cell model method was adopted to set up the model.

  15. 锅炉化学清洗过程监督的意义与要点%Significance and points of the monitoring in boiler chemical cleaning process

    Institute of Scientific and Technical Information of China (English)

    刘绍银; 李善风

    2011-01-01

    From the structural characteristics of the boiler equipment,cleaning results of evaluation methods,technical expertise,cleaning of the market factors,analysied the meaning of supervision of boiler chemical cleaning process;with the technical supervision of the whole process of thinking;and analysied the qualification and capacity,technical program,the temporary system,drug control,cleaning,process monitoring,cleaning outcome assessment,summary report of the technical aspects of monitoring points.%从锅炉设备结构特点、清洗结果评定方法、技术人员专业水平、清洗工作的市场因素等方面,分析了加强锅炉化学清洗的过程监督的意义;用全过程技术监督的思想,分析了资质与能力、技术方案、临时系统、药品控制、清洗过程监控、清洗结果评估、总结报告各环节技术监督的要点。

  16. An annular-furnace boiler for the 660-MW power unit for ultrasupercritical parameters intended for firing brown slagging coals

    Science.gov (United States)

    Serant, F. A.; Belorutskii, I. Yu.; Ershov, Yu. A.; Gordeev, V. V.; Stavskaya, O. I.; Katsel, T. V.

    2013-12-01

    We present the main technical solutions adopted in designing annular-furnace boilers intended for operation on brown coals of the prospective Maikubensk open-cast mine in Kazakhstan as part of 660-MW power units for ultrasupercritical steam conditions. Results from 3D modeling of combustion processes are presented, which clearly show the advantages furnaces of this kind have over a traditional furnace in burning heavily slagging brown coals. The layout of the main and boiler auxiliary equipment in the existing boiler cell of the 500-MW power unit at the Ekibastuz GRES-1 district power station is shown. Appropriate attention is paid to matters concerned with decreasing harmful emissions.

  17. Computer system for monitoring power boiler operation

    Energy Technology Data Exchange (ETDEWEB)

    Taler, J.; Weglowski, B.; Zima, W.; Duda, P.; Gradziel, S.; Sobota, T.; Cebula, A.; Taler, D. [Cracow University of Technology, Krakow (Poland). Inst. for Process & Power Engineering

    2008-02-15

    The computer-based boiler performance monitoring system was developed to perform thermal-hydraulic computations of the boiler working parameters in an on-line mode. Measurements of temperatures, heat flux, pressures, mass flowrates, and gas analysis data were used to perform the heat transfer analysis in the evaporator, furnace, and convection pass. A new construction technique of heat flux tubes for determining heat flux absorbed by membrane water-walls is also presented. The current paper presents the results of heat flux measurement in coal-fired steam boilers. During changes of the boiler load, the necessary natural water circulation cannot be exceeded. A rapid increase of pressure may cause fading of the boiling process in water-wall tubes, whereas a rapid decrease of pressure leads to water boiling in all elements of the boiler's evaporator - water-wall tubes and downcomers. Both cases can cause flow stagnation in the water circulation leading to pipe cracking. Two flowmeters were assembled on central downcomers, and an investigation of natural water circulation in an OP-210 boiler was carried out. On the basis of these measurements, the maximum rates of pressure change in the boiler evaporator were determined. The on-line computation of the conditions in the combustion chamber allows for real-time determination of the heat flowrate transferred to the power boiler evaporator. Furthermore, with a quantitative indication of surface cleanliness, selective sootblowing can be directed at specific problem areas. A boiler monitoring system is also incorporated to provide details of changes in boiler efficiency and operating conditions following sootblowing, so that the effects of a particular sootblowing sequence can be analysed and optimized at a later stage.

  18. NOx CONTROL OPTIONS AND INTEGRATION FOR US COAL FIRED BOILERS

    Energy Technology Data Exchange (ETDEWEB)

    Mike Bockelie; Marc Cremer; Kevin Davis; Connie Senior; Bob Hurt; Eric Eddings; Larry Baxter

    2001-10-10

    This is the fifth 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 firing US coals. The Electric Power Research Institute (EPRI) is providing cofunding for this program. This program contains multiple tasks and good progress is being made on all fronts. Field tests for NOx reduction in a cyclone fired utility boiler due to using Rich Reagent Injection (RRI) have been started. CFD modeling studies have been started to evaluate the use of RRI for NOx reduction in a corner fired utility boiler using pulverized coal. Field tests of a corrosion monitor to measure waterwall wastage in a utility boiler have been completed. Computational studies to evaluate a soot model within a boiler simulation program are continuing. Research to evaluate SCR catalyst performance has started. A literature survey was completed. Experiments have been outlined and two flow reactor systems have been designed and are under construction. Commercial catalyst vendors have been contacted about supplying catalyst samples. Several sets of new experiments have been performed to investigate ammonia removal processes and mechanisms for fly ash. Work has focused on a promising class of processes in which ammonia is destroyed by strong oxidizing agents at ambient temperature during semi-dry processing (the use of moisture amounts less than 5 wt-%). Both ozone and an ozone/peroxide combination have been used to treat both basic and acidic ammonia-laden ashes.

  19. NOx CONTROL OPTIONS AND INTEGRATION FOR US COAL FIRED BOILERS

    Energy Technology Data Exchange (ETDEWEB)

    Mike Bockelie; Marc Cremer; Kevin Davis; Connie Senior; Bob Hurt; Eric Eddings; Larry Baxter

    2001-10-10

    This is the fifth 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 firing US coals. The Electric Power Research Institute (EPRI) is providing cofunding for this program. This program contains multiple tasks and good progress is being made on all fronts. Field tests for NOx reduction in a cyclone fired utility boiler due to using Rich Reagent Injection (RRI) have been started. CFD modeling studies have been started to evaluate the use of RRI for NOx reduction in a corner fired utility boiler using pulverized coal. Field tests of a corrosion monitor to measure waterwall wastage in a utility boiler have been completed. Computational studies to evaluate a soot model within a boiler simulation program are continuing. Research to evaluate SCR catalyst performance has started. A literature survey was completed. Experiments have been outlined and two flow reactor systems have been designed and are under construction. Commercial catalyst vendors have been contacted about supplying catalyst samples. Several sets of new experiments have been performed to investigate ammonia removal processes and mechanisms for fly ash. Work has focused on a promising class of processes in which ammonia is destroyed by strong oxidizing agents at ambient temperature during semi-dry processing (the use of moisture amounts less than 5 wt-%). Both ozone and an ozone/peroxide combination have been used to treat both basic and acidic ammonia-laden ashes.

  20. Process of heavy oil thermal recovery wastewater reused as power plant boiler make-up water%稠油热采废水回用电站锅炉补给水工艺

    Institute of Scientific and Technical Information of China (English)

    王璟; 毛进; 赵剑强; 蒲平; 郭维忠; 李亚娟; 刘亚鹏

    2015-01-01

    常规稠油热采废水处理采用除油软化工艺,出水水质较低,仅能用于直流小注汽锅炉补水.由于小注汽锅炉参数低,排污量大,能耗高,造成采油蒸汽成本高.针对该问题,开发了预处理-蒸发-生物处理-膜处理-混床工艺处理稠油热采废水,并通过实验对工艺各子系统运行性能进行研究以提高处理效果,使系统处理出水可用于电站高参数锅炉补给水,达到以热电联产机组取代小注汽锅炉,降低采油蒸汽费用的目的.研究结果表明,采用该工艺对稠油热采废水进行处理,各子系统运行稳定;废水经除硅软化预处理及蒸发后,产水TOC平均约22mg/L;曝气生物滤池产水TOC平均约6mg/L;再经超滤-反渗透处理后产水TOC含量小于0.15mg/L;继续经混床处理,最终出水电导率≤0.15μS/cm、二氧化硅≤10μg/L、TOC≤200μg/L,满足电站高参数锅炉补水水质要求,每吨水直接运行费用为8.05元.%The traditional heavy oil thermal recovery wastewater treatment process is comprised of oil eliminating and softening. The effluent quality is comparably poor which can only be used as make up water for once-through small steam injection boiler. Because the parameter of small steam injection boiler is low,both the boiler blowdown and energy consumption are high. The oil extraction steam cost is raised subsequently. Aimed at the problem,a novel heavy oil thermal recovery wastewater treatment process that comprises of pretreatment,bio-treatment,membrane,and mixed bed technology was developed. Operating performance of individual sub-system was investigated by model experiments to enhance the treatment efficiency and to make it possible to reuse the product water as high parameter power plant unit make up water. As a result,the objective to replace the small steam injection boiler by combined heat and power generation unit to reduce the oil extraction steam fee could be achieved. Results show that the operating

  1. New thinking for the boiler room.

    Science.gov (United States)

    Rose, Wayne

    2008-09-01

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

  2. Visualisation of the velocity field in a scaled water model for validation of numerical calculations for a powder fuelled boiler

    Energy Technology Data Exchange (ETDEWEB)

    Dumortier, Laurent [Luleaa Univ. of Technology (Sweden)

    2001-01-01

    Validation of numerical predictions of the flow field in a powder fired industry boiler by flow visualisation in a water model has been studied. The bark powder fired boiler at AssiDomaen Kraftliner in Piteaa has been used as a case study. A literature study covering modelling of combusting flows by water models and different flow visualisation techniques has been carried out. The main conclusion as regards the use of water models is that only qualitative information can be expected. As far as turbulent flow is assured in the model as well as the real furnace, the same Reynolds number is not required. Geometrical similarity is important but modelling of burner jets requires adaptation of the jet diameters in the model. Guidelines for this are available and are presented in the report. The review of visualisation techniques shows that a number of methods have been used successfully for validation of flow field predictions. The conclusion is that the Particle Image Velocimetry and Particle Tracking Velocimetry methods could be very suitable for validation purposes provided that optical access is possible. The numerical predictions include flow fields in a 1130 scale model of the AssiDomaen furnace with water flow as well as flow and temperature fields in the actual furnace. Two burner arrangements were considered both for the model and the actual furnace, namely the present configuration with four front burners and a proposed modification where an additional burner is positioned at a side wall below the other burners. There are many similarities between the predicted flow fields in the model and the full scale furnace but there are also some differences, in particular in the region above the burners and the effects of the low region re-circulation on the lower burner jets. The experiments with the water model have only included the arrangement with four front burners. There were problems determining the velocities in the jets and the comparisons with predictions are

  3. 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.

  4. Application of energy and exergy analysis to increase efficiency of a hot water gas fired boiler

    Directory of Open Access Journals (Sweden)

    Todorović Milena N.

    2014-01-01

    Full Text Available In engineering practice exergy can be used for technical and economic optimization of energy conversion processes. The problem of increasing energy consumption suggests that heating plants, i.e. hot water boilers, as energy suppliers for household heating should be subjected to exergy and energy analysis. Heating plants are typically designed to meet energy demands, without the distinguished difference between quality and quantity of the produced heat. In this paper, the energy and exergy analysis of a gas fired hot water boiler is conducted. Energy analysis gives only quantitative results, while exergy analysis provides an insight into the actually available useful energy with respect to the system environment. In this paper, a hot water boiler was decomposed into control volumes with respect to its functional components. Energy and exergy of the created physical model of the hot water boiler is performed and destruction of exergy and energy loss in each of the components is calculated. The paper describes the current state of energy and exergy efficiency of the hot water boiler. The obtained results are analyzed and used to investigate possibilities for improvement of availability and reliability of the boiler. A comparison between the actual and the proposed more reliable solution is made.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-31

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

  6. CFD analysis of the pulverized coal combustion processes in a 160 MWe tangentially-fired-boiler of a thermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Cristiano V. da; Beskow, Arthur B. [Universidade Regional Integrada do Alto Uruguai e das Misses (LABSIM/GEAPI/URI), Erechim, RS (Brazil). Dept. de Engenharia e Ciencia da Computacao. Grupo de Engenharia Aplicada a Processos Industriais], Emails: cristiano@uricer.edu.br, Arthur@uricer.edu.br; Indrusiak, Maria Luiza S. [Universidade do Vale do Rio dos Sinos (UNISINOS), Sao Leopoldo, RS (Brazil). Programa de Engenharia Mecanica], E-mail: sperbindrusiak@via-rs.net

    2010-10-15

    The strategic role of energy and the current concern with greenhouse effects, energetic and exegetic efficiency of fossil fuel combustion greatly enhance the importance of the studies of complex physical and chemical processes occurring inside boilers of thermal power plants. The state of the art in computational fluid dynamics and the availability of commercial codes encourage numeric studies of the combustion processes. In the present work the commercial software CFX Ansys Europe Ltd. was used to study the combustion of coal in a 160 MWe commercial thermal power plant with the objective of simulating the operational conditions and identifying factors of inefficiency. The behavior of the flow of air and pulverized coal through the burners was analyzed, and the three-dimensional flue gas flow through the combustion chamber and heat exchangers was reproduced in the numeric simulation. (author)

  7. Numerical studies of the combustion of fuel oil in the boiler furnace at reduced load

    Directory of Open Access Journals (Sweden)

    Ivantsov Aleksandr A.

    2014-01-01

    Full Text Available Relevance of the work due to the need to assess the effectiveness and reliability of the boiler units on reserve fuel after reconstruction associated with a change in the base fuel and approaches of numerical analysis. Analysis of physical and chemical processes in the furnace volume of boiler BKZ–210–140 operating on reserve fuel and rated load when using the Euler and Euler combined and Lagrangian modeling approaches. Results of the numerical modeling of the processes of aerodynamics, heat exchange, and combustion in the furnace volume.

  8. Mechanical Design of Steel Tubing for Use in Black Liquor Recovery Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Taljat, B.; Zacharaia, T.; Wang, X.; Kesier, J.; Swindeman, R.; Hubbard, C.

    1999-05-26

    Finite element models were developed for thermal-mechanical analysis of black liquor recovery boiler floor tubes. Residual stresses in boiler floors due to various manufacturing processes were analyzed. The modeling results were verified by X-ray and neutron diffraction measurements at room temperature on as-manufactured tubes as well as tubes after service. The established finite element models were then used to evaluate stress conditions during boiler operation. Using these finite element models, a parametric response surface study was performed to investigate the influence of material properties of the clad layer on stresses in the floor tubes during various boiler operating conditions, which yielded a generalized solution of stresses in the composite tube floors. The results of the study are useful for identifying the mechanisms of cracking experienced by recovery boilers. Based on the results of the response surface study, a recommendation was made for more suitable materials in terms of the analyzed mechanical properties. Alternative materials and manufacturing processes are being considered to improve the resistance to cracking and the in-service life of composite tubes. To avoid numerous FE stress-strain analyses of composite tubes made of different material combinations, a response surface study was performed that considered two essential mechanical properties of the clad material - coefficient of thermal expansion and yield stress - as independent variables. The response surface study provided a generalized solution of stresses in the floor in terms of the two selected parameters.

  9. A new air-fuel WSGGM for better utility boiler simulation, design and optimization

    DEFF Research Database (Denmark)

    Yin, Chungen

    in computational fluid dynamics (CFD) simulation of air-fuel combustion processes. The WSGGM coefficients evaluated by Smith et al. (1982) for several partial pressures of CO2 and H2O vapor are often used for gas temperatures up to 2400K, which is supplemented by the coefficient values presented by Coppalle...... and Vervisch (1983) for higher temperatures until 3000K. This paper refines the WSGGM in terms of accuracy, completeness and implementation, and demonstrates the use and impacts of the refined model in CFD simulation of a conventional air-fuel utility boiler.......Radiation is the principal mode of heat transfer in utility boiler furnaces. Models for radiative properties play a vital role in reliable simulations of utility boilers and simulation-based design and optimization. The weighted sum of gray gases model (WSGGM) is one of the most widely used models...

  10. 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.

  11. A Rule-Based Industrial Boiler Selection System

    Science.gov (United States)

    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.

    2015-09-01

    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, super heaters, air heaters and economizers. The selection of the boiler is very important to the industry for conducting the operation system successfully. The selection criteria are based on rule based expert system and multi-criteria weighted average method. The developed system consists of Knowledge Acquisition Module, Boiler Selection Module, User Interface Module and Help Module. The system capable of selecting the suitable boiler based on criteria weighted. The main benefits from using the system is to reduce the complexity in the decision making for selecting the most appropriate boiler to palm oil process plant.

  12. Soft computing approach for modeling power plant with a once-through boiler

    Energy Technology Data Exchange (ETDEWEB)

    Ghaffari, Ali; Chaibakhsh, Ali [Department of Mechanical Engineering, K.N. Toosi University of Technology, P.O. Box 16765-3381, Tehran, (Iran); Lucas, Caro [Department of Electrical and Computer Engineering, University of Tehran, P.O. Box 14318, Tehran, (Iran)

    2007-09-15

    In this paper, a soft computing approach is presented for modeling electrical power generating plants in order to characterize the essential dynamic behavior of the plant subsystems. The structure of the soft computing method consists of fuzzy logic, neural networks and genetic algorithms. The measured data from a complete set of field experiments is the basis for training the models including the extraction of linguistic rules and membership functions as well as adjusting the other parameters of the fuzzy model. The genetic algorithm is applied to the modeling approach in order to optimize the procedure of the training. Comparison between the responses of the proposed models with the responses of the plants validates the accuracy and performance of the modeling approach. A similar comparison between the responses of these models with the models obtained based on the thermodynamical and physical relations of the plant shows the effectiveness and feasibility of the developed model in terms of more accurate and less deviation between the responses of the models and the corresponding subsystems. (Author)

  13. 锅炉效率视角下运行参数的分析与探讨%Analysis and Discussion on Boiler Operating Parameters under Efficiency Perspective

    Institute of Scientific and Technical Information of China (English)

    王庆勇; 陈孟婷; 陈潇阳

    2014-01-01

    锅炉在现代工业中有广泛的应用,研究锅炉运行机制,提高锅炉效率显得尤为重要。在研究锅炉运行参数对锅炉效率的影响中,影响锅炉效率因素主要有排烟温度、灰渣可燃物、送风温度、给水温度、蒸汽压力等。通过查阅文献并结合锅炉的实际情况,构建了每种参数对锅炉效率影响的模型。以NOx与锅炉效率为核心建立多目标优化模型,讨论了NOx对锅炉效率的影响,可指导运行人员优化燃烧流程,进而提高锅炉效率。%The boiler is widely used in modern industry, to study the operation mechanism of boiler and improve boiler efficiency are particularly important. In the research of the impact of boiler operating parameters on boiler efficiency, the main factors affecting the efficiency are mainly exhaust gas temperature, ash fuel, air temperature, water temperature, steam pressure and so on. Through literature and the actual situation of the boiler, the model was constructed for each parameter influence on boiler efficiency. The multi-objective optimization model as the core of NOx and boiler efficiency was built, the effects of NOx on boiler efficiency was discussed, which can guide operators to optimize the combustion process, thus improving the boiler efficiency.

  14. Shape optimization of a thick-walled power boiler component

    Directory of Open Access Journals (Sweden)

    Duda Piotr

    2017-01-01

    Full Text Available This paper presents a methodology and successful application of structural optimization of a T-pipe under transient thermal and mechanical loads. In order to find the optimal shape of a thick-walled power boiler component, a parametric FE model and the evolutionary algorithm (EA are applied. The power boiler start-up and shutdown curves are based on the TRD 301 guidelines. Maximum total stresses are assumed as optimization constraints. The obtained geometry is by about 18.6% lighter than the original one due to thinning of the walls. Maximum tensile and compressive stresses in the modified geometry are smaller than in the original one during the whole cycle. Additionally, lower total stress values are recorded during heating and cooling processes. Therefore, these transient processes can be accelerated and the shutdown and start-up losses can be reduced.

  15. Modeling multiphase materials processes

    CERN Document Server

    Iguchi, Manabu

    2010-01-01

    ""Modeling Multiphase Materials Processes: Gas-Liquid Systems"" describes the methodology and application of physical and mathematical modeling to multi-phase flow phenomena in materials processing. The book focuses on systems involving gas-liquid interaction, the most prevalent in current metallurgical processes. The performance characteristics of these processes are largely dependent on transport phenomena. This volume covers the inherent characteristics that complicate the modeling of transport phenomena in such systems, including complex multiphase structure, intense turbulence, opacity of

  16. Product Development Process Modeling

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The use of Concurrent Engineering and other modern methods of product development and maintenance require that a large number of time-overlapped "processes" be performed by many people. However, successfully describing and optimizing these processes are becoming even more difficult to achieve. The perspective of industrial process theory (the definition of process) and the perspective of process implementation (process transition, accumulation, and inter-operations between processes) are used to survey the method used to build one base model (multi-view) process model.

  17. Towards a CFD-based mechanistic deposit formation model for straw-fired boilers

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen; Rosendahl, Lasse Aistrup; Baxter, L.L.

    2006-01-01

    in the reminder of the paper. The growth of deposits on furnace walls and super heater tubes is treated including the impact on heat transfer rates determined by the CFD code. Based on the commercial CFD code FLUENTe, the overall model is fully implemented through the User Defined Functions. The model...... is configured entirely through a graphical user interface integrated in the standard FLUENTe interface. The model considers fine and coarse mode ash deposition and sticking mechanisms for the complete deposit growth, as well as an influence on the local boundary conditions for heat transfer due to thermal...

  18. Research and application of multiple model predictive control in Ultra-supercritical boiler-turbine system

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Hengfeng; Yan, Weiwu; Wang, Guoliang; Hu, Yong; Li, Nan [Shanghai Jiao Tong Univ., Shanghai (China). Dept. of Automation; Ministry of Education of China, Shanghai (China). Key Lab. of System Control and Information Processing; Chen, Shihe; Zhang, Xi [Guangdong Electric Power Research Institute, Guangzhou (China)

    2013-07-01

    Based on analyzing the characteristics of Ultra-supercritical unit, this paper introduced a multiple model MCPC (Multivariable Constrained Predictive Control) structure with three inputs and three outputs for coordination control of Ultra-supercritical unit. In the structure, double-layer structure of optimization was used to obtain good steady and dynamic performance, and piecewise linear models at the different operating points of Ultra-supercritical unit were used to deal with nonlinearity. In the real-time simulation, nonlinear model of 1000MW Ultra-supercritical unit in was considered. Finally, the result of real-time simulation was given in the paper.

  19. Process modeling style

    CERN Document Server

    Long, John

    2014-01-01

    Process Modeling Style focuses on other aspects of process modeling beyond notation that are very important to practitioners. Many people who model processes focus on the specific notation used to create their drawings. While that is important, there are many other aspects to modeling, such as naming, creating identifiers, descriptions, interfaces, patterns, and creating useful process documentation. Experience author John Long focuses on those non-notational aspects of modeling, which practitioners will find invaluable. Gives solid advice for creating roles, work produ

  20. Product and Process Modelling

    DEFF Research Database (Denmark)

    Cameron, Ian T.; Gani, Rafiqul

    This book covers the area of product and process modelling via a case study approach. It addresses a wide range of modelling applications with emphasis on modelling methodology and the subsequent in-depth analysis of mathematical models to gain insight via structural aspects of the models. These ...

  1. 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.

  2. Physical characterization of biomass fuels prepared for suspension firing in utility boilers for CFD modelling

    DEFF Research Database (Denmark)

    Rosendahl, Lasse; Yin, Chungen; Kær, Søren Knudsen

    2007-01-01

    shapes. The sample is subdivided by straw type, and coherent size, type and mass distribution parameters are reported for the entire sample. This type of data is necessary in order to use CFD reliably as a design and retrofit tool for co-firing biomass with fossil fuels, as the combustion processes...

  3. Static and Transient Performance Prediction for CFB Boilers Using a Bayesian—Gaussian Neural Network

    Institute of Scientific and Technical Information of China (English)

    HaiwenYe; WeidouNi

    1997-01-01

    A bayesian-Gaussian Neural Network(BGNN)is put forward in this paper to predict the static and transient performance of Circulating Fluidized Bed(CFB) boilers.The advantages of this network over Back-Propagation Neural Networks(BPNNs),easier determination of topology,simpler and time saving in training process as well as self-organizing bility,make this network more practical in on-line performance prediction for complicatied processes,Simulation shows that this network is comparable to the BPNNs in predicting the performance of CFB boilers.Good and practical on-line performance predictions are essential for operation guide and model predictive control of CFB boilers,which are under research by the authors.

  4. Product and Process Modelling

    DEFF Research Database (Denmark)

    Cameron, Ian T.; Gani, Rafiqul

    This book covers the area of product and process modelling via a case study approach. It addresses a wide range of modelling applications with emphasis on modelling methodology and the subsequent in-depth analysis of mathematical models to gain insight via structural aspects of the models....... These approaches are put into the context of life cycle modelling, where multiscale and multiform modelling is increasingly prevalent in the 21st century. The book commences with a discussion of modern product and process modelling theory and practice followed by a series of case studies drawn from a variety...... to biotechnology applications, food, polymer and human health application areas. The book highlights to important nature of modern product and process modelling in the decision making processes across the life cycle. As such it provides an important resource for students, researchers and industrial practitioners....

  5. Dynamic Simulation of an Organic Rankine Cycle—Detailed Model of a Kettle Boiler

    Directory of Open Access Journals (Sweden)

    Roberto Pili

    2017-04-01

    Full Text Available Organic Rankine Cycles (ORCs are nowadays a valuable technology to produce electricity from low and medium temperature heat sources, e.g., in geothermal, biomass and waste heat recovery applications. Dynamic simulations can help improve the flexibility and operation of such plants, and guarantee a better economic performance. In this work, a dynamic model for a multi-pass kettle evaporator of a geothermal ORC power plant has been developed and its dynamics have been validated against measured data. The model combines the finite volume approach on the tube side and a two-volume cavity on the shell side. To validate the dynamic model, a positive and a negative step function in heat source flow rate is applied. The simulation model performed well in both cases. The liquid level appeared the most challenging quantity to simulate. A better agreement in temperature was achieved by increasing the volume flow rate of the geothermal brine by 2% over the entire simulation. Measurement errors, discrepancies in working fluid and thermal brine properties and uncertainties in heat transfer correlations can account for this. In the future, the entire geothermal power plant will be simulated, and suggestions to improve its dynamics and control by means of simulations will be provided.

  6. Standard Model processes

    CERN Document Server

    Mangano, M.L.; Aguilar Saavedra, J.A.; Alekhin, S.; Badger, S.; Bauer, C.W.; Becher, T.; Bertone, V.; Bonvini, M.; Boselli, S.; Bothmann, E.; Boughezal, R.; Cacciari, M.; Carloni Calame, C.M.; Caola, F.; Campbell, J.M.; Carrazza, S.; Chiesa, M.; Cieri, L.; Cimaglia, F.; Febres Cordero, F.; Ferrarese, P.; D'Enterria, D.; Ferrera, G.; Garcia i Tormo, X.; Garzelli, M.V.; Germann, E.; Hirschi, V.; Han, T.; Ita, H.; Jäger, B.; Kallweit, S.; Karlberg, A.; Kuttimalai, S.; Krauss, F.; Larkoski, A.J.; Lindert, J.; Luisoni, G.; Maierhöfer, P.; Mattelaer, O.; Martinez, H.; Moch, S.; Montagna, G.; Moretti, M.; Nason, P.; Nicrosini, O.; Oleari, C.; Pagani, D.; Papaefstathiou, A.; Petriello, F.; Piccinini, F.; Pierini, M.; Pierog, T.; Pozzorini, S.; Re, E.; Robens, T.; Rojo, J.; Ruiz, R.; Sakurai, K.; Salam, G.P.; Salfelder, L.; Schönherr, M.; Schulze, M.; Schumann, S.; Selvaggi, M.; Shivaji, A.; Siodmok, A.; Skands, P.; Torrielli, P.; Tramontano, F.; Tsinikos, I.; Tweedie, B.; Vicini, A.; Westhoff, S.; Zaro, M.; Zeppenfeld, D.; CERN. Geneva. ATS Department

    2017-06-22

    This report summarises the properties of Standard Model processes at the 100 TeV pp collider. We document the production rates and typical distributions for a number of benchmark Standard Model processes, and discuss new dynamical phenomena arising at the highest energies available at this collider. We discuss the intrinsic physics interest in the measurement of these Standard Model processes, as well as their role as backgrounds for New Physics searches.

  7. An inverse method for online stress monitoring and fatigue life analysis of boiler drums

    Institute of Scientific and Technical Information of China (English)

    HU Wen-sen; LI Bin; CAO Zi-dong; YANG Dong; LI Ya-chao

    2009-01-01

    A method based on solution of the inverse heat conduction problem was presented for online stress monitoring and fatigue life analysis of boiler drums. The mathematical model of the drum temperature distribution is based on the assumptions that the difference of temperature along the longitudinal axis of the boiler drum is negligible with changes only in the radial direction and the circumferential direction, and that the outer surface of drum is thermally insulated. Combining this model with the control-volume method provides temperatures at different points on a eross-section of the drum. With the temperature data, the stresses and the life expectancy of the boiler drum are derived according to the ASME code. Applying this method to the cold start-up process of a 300 MW boiler demonswated the absence of errors caused by the boundary condition assumptions on the inner surface of the drum and testified that the method is an applicable technique for the online stress monitoring and fatigue life analysis of boiler drums.

  8. A Cold Model Experimental Study on the Flow Characterisitcs of Bed Baterial in A Fluidized ed Bottom Ash Cooler in a CFB Boiler

    Institute of Scientific and Technical Information of China (English)

    LuXiaofeng; LiYourong

    2000-01-01

    A cold model experimental study on the flowing characteristics of bed meterial between a fluidized bed ash cooler and a furnace of CFB boiler were discussed in this paper.The research results showed that flowing status of the bed material in a bubbling bed,which was run with a circulating fluidized bed together in parallel operation,was influenced by the pressure difference between the CFB and the bubbling bed,the switch status of unlocking air ,and the structure of the exit of the bubbling bed.There was a circulating flow of bed material between CFB and bubbling bed.

  9. 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...... 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...... 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...

  10. CFD investigation of flow through internally riffled boiler tubes

    DEFF Research Database (Denmark)

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

    1997-01-01

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

  11. Process for simultaneous separation of SO/sub 2/ and NO/sub x/ from stack gases of boilers. Verfahren zur simultanen SO/sub 2/ und NO/sub x/-Abscheidung aus den Rauchgasen von Verbrennungskesseln

    Energy Technology Data Exchange (ETDEWEB)

    Hoelter, H.; Igelbuescher, H.; Gresch, H.; Dewert, H.

    1987-04-30

    The process for the simultaneous separation of SO/sub 2/ and NO/sub x/ from the stack gases of boilers, in which the additives lime, lime hydrate, iron chelate compound, polycarbon acids, washing liquids containing CaSO/sub 4/ and CaSO/sub 3/ are used and the washing liquids are added to the reducing additive via a solid/liquid separation stage, giving up the inactive filtrate water in a reaction container, are taken away and are returned from here to the washing water reservoir and/or to the washer, characterized by the fact that a part of the filtrate water, before being passed to the reaction container, is introduced into the combustion space of the boiler or is sprayed on to the coal fuel before its introduction into the boiler. In this way, a technique without waste water is attained, as the filtrate water with its cargo of salts is burnt in an environmentally acceptable way at high temperature in the combustion space of the boiler and the residues are bound in its ash.

  12. 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.)

  13. Control Properties of Bottom Fired Marine Boilers

    DEFF Research Database (Denmark)

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

    2005-01-01

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

  14. 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.

  15. Business Process Modeling: Blueprinting

    OpenAIRE

    Al-Fedaghi, Sabah

    2017-01-01

    This paper presents a flow-based methodology for capturing processes specified in business process modeling. The proposed methodology is demonstrated through re-modeling of an IBM Blueworks case study. While the Blueworks approach offers a well-proven tool in the field, this should not discourage workers from exploring other ways of thinking about effectively capturing processes. The diagrammatic representation presented here demonstrates a viable methodology in this context. It is hoped this...

  16. Modeling of large-scale oxy-fuel combustion processes

    DEFF Research Database (Denmark)

    Yin, Chungen

    2012-01-01

    , among which radiative heat transfer under oxy-fuel conditions is one of the fundamental issues. This paper demonstrates the nongray-gas effects in modeling of large-scale oxy-fuel combustion processes. Oxy-fuel combustion of natural gas in a 609MW utility boiler is numerically studied, in which....... The simulation results show that the gray and non-gray calculations of the same oxy-fuel WSGGM make distinctly different predictions in the wall radiative heat transfer, incident radiative flux, radiative source, gas temperature and species profiles. In relative to the non-gray implementation, the gray...

  17. 火电厂炉水加药处理技术探析%Analysis of Boiler Water Dosing Processing Technology in Power Plant

    Institute of Scientific and Technical Information of China (English)

    张晓玮

    2014-01-01

    目前在汽包锅炉水的处理中应用最广泛的是炉水磷酸盐处理技术。本文着重对此技术进行了分析和探讨。%At present, the boiler water phosphate treatment technology is the most widely used in steam drum boiler water treatment. In this paper, this technology is analyzed and discussed.

  18. 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.

  19. Predicate Model on NOx Emission of a High Capacity Firing Boiler%大型燃煤锅炉氮氧化物排放预测模型

    Institute of Scientific and Technical Information of China (English)

    凡荣荣; 杨巨生; 谢克昌

    2012-01-01

    随着环保要求的不断提高,大型燃煤电厂锅炉的NOx排放特性日益受到关注。借助某600MW锅炉燃烧调整试验数据,采用BP-adaboost算法建立了NOx排放特性的预测模型。研究结构表明,与BP神经网络建立的NOx特性排放模型相比,该模型能根据燃煤特性及各种操作参数更加准确预测锅炉在不同工况下NOx排放特性。%With the development of the restricted environmental protection demand,more attention is paid to the NOx emission property of the high capacity tangential firing boiler.The estimation model has been established by means of BP-adaboost based on a 600MW boiler combustion adjustment testing data.It is proven by the research result that such a model can predicate the NOx emission more accurate than that established by BP network under various operating conditions.

  20. Control Properties of Bottom Fired Marine Boilers

    DEFF Research Database (Denmark)

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

    2007-01-01

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

  1. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Levasseur, Armand

    2014-04-30

    fuels, oxy-process variables and boiler design parameters. Significant improvement of CFD modeling tools and validation against 15 MWth experimental data has been completed. Oxy-boiler demonstration and large reference designs have been developed, supported with the information and knowledge gained from the 15 MWth testing. This report addresses the results from the 15 MWth testing in the BSF.

  3. Influence of boiler load on water tubes burnout

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-07-01

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

  4. Process for simultaneous SO/sub 2/ and NO/sub x/ separation from the stack gases of boilers. Verfahren zur simultanen SO/sub 2/- und NO/sub x/-Ausscheidung aus den Rauchgasen von Verbrennungskesseln

    Energy Technology Data Exchange (ETDEWEB)

    Hoelter, H.; Igelbuescher, H.; Gresch, H.; Dewert, H.

    1987-06-11

    The main patent application P 3429663.8.43 concerns a process for the simultaneous separation of SO/sub 2/ and NO/sub x/ from the stack gases of combustion boilers, where a liquid which is used with additives such as lime or hydrated lime and EDTA or NTA and/or polycarbonic acids and CaSO/sub 4/ or CaSO/sub 3/ is used for washing, is activated as a part quantity via a solid/liquid separation stage giving up inactive liquid into a reaction container, in which a reducing additive is added and is returned by means of a pump and the washing water reservoir via an inlet level, and/or is made directly available again via pairs of nozzles for the washing process, where a part quantity of the filtrate water is introduced before its activation, loaded with N + S salts, into the combustion space of the boiler and/or is added to the coal fuel before supplying it to the boiler. Sodium bisulphite, ascorbic acid, sodium diothionite and similar means of reduction are used in this process. In order to improve the process according to the main patent application further, the invention proposes that before extracting the part quantity of filtrate water laden with N + S salts, there should be precipitation of the EDTA and its return to the washing water circuit.

  5. Business Model Process Configurations

    DEFF Research Database (Denmark)

    Taran, Yariv; Nielsen, Christian; Thomsen, Peter

    2015-01-01

    Purpose – The paper aims: 1) To develop systematically a structural list of various business model process configuration and to group (deductively) these selected configurations in a structured typological categorization list. 2) To facilitate companies in the process of BM innovation......, by developing (inductively) an ontological classification framework, in view of the BM process configurations typology developed. Design/methodology/approach – Given the inconsistencies found in the business model studies (e.g. definitions, configurations, classifications) we adopted the analytical induction...... method of data analysis. Findings - A comprehensive literature review and analysis resulted in a list of business model process configurations systematically organized under five classification groups, namely, revenue model; value proposition; value configuration; target customers, and strategic...

  6. SDG-based Model Validation in Chemical Process Simulation

    Institute of Scientific and Technical Information of China (English)

    张贝克; 许欣; 马昕; 吴重光

    2013-01-01

    Signed direct graph (SDG) theory provides algorithms and methods that can be applied directly to chemical process modeling and analysis to validate simulation models, and is a basis for the development of a soft-ware environment that can automate the validation activity. This paper is concentrated on the pretreatment of the model validation. We use the validation scenarios and standard sequences generated by well-established SDG model to validate the trends fitted from the simulation model. The results are helpful to find potential problems, as-sess possible bugs in the simulation model and solve the problem effectively. A case study on a simulation model of boiler is presented to demonstrate the effectiveness of this method.

  7. WWTP Process Tank Modelling

    DEFF Research Database (Denmark)

    Laursen, Jesper

    hydrofoil shaped propellers. These two sub-processes deliver the main part of the supplied energy to the activated sludge tank, and for this reason they are important for the mixing conditions in the tank. For other important processes occurring in the activated sludge tank, existing models and measurements...

  8. 糖厂锅炉的分析模型研究%Study on Exergy Analysis Model of Boiler in Cane Sugar Mills

    Institute of Scientific and Technical Information of China (English)

    郝媛媛; 张艳军

    2014-01-01

    甘蔗制糖业是广西支柱产业,并且是高能耗行业。以某日榨7000吨的甘蔗糖厂为例,对其锅炉建立分析模型并进行了能量分析,结果效率比热效率低一半左右。分析模型揭示了糖厂锅炉的能耗来源,为糖厂锅炉的节能降耗优化改造提供了理论支持。%Cane sugar manufacturing industry was a main industry in Guangxi, and was a highly energy-consuming trade. Taking a sugar mill of daily output of 7 000 t and making an exergy analysis of its boiler, the results showed that the exergy efficiency was lower about a half than that of the thermal efficiency. The exergy analysis model showed the origin of the energy loss, and could provide theoretical support for energy saving and optimal modification of the boiler in cane sugar mills.

  9. Electric Boiler and Heat Pump Thermo-Electrical Models for Demand Side Management Analysis in Low Voltage Grids

    DEFF Research Database (Denmark)

    Diaz de Cerio Mendaza, Iker; Bak-Jensen, Birgitte; Chen, Zhe

    2013-01-01

    The last fifteen years many European countries have integrated large percentage of renewable energy on their electricity generation mix. In Denmark the 21.3% of the electricity consumed nowadays is produced by the wind, and it has planned to be the 50% by 2025. In order to front future challenges...... on the power system control and operation, created by this unstable way of generation, Demand Side Management turns to be a promising solution. The storage capacity from thermo-electric units, like electric boilers and heat pumps, allows operating them with certain freedom. Hence they can be employed under...

  10. Biosphere Process Model Report

    Energy Technology Data Exchange (ETDEWEB)

    J. Schmitt

    2000-05-25

    To evaluate the postclosure performance of a potential monitored geologic repository at Yucca Mountain, a Total System Performance Assessment (TSPA) will be conducted. Nine Process Model Reports (PMRs), including this document, are being developed to summarize the technical basis for each of the process models supporting the TSPA model. These reports cover the following areas: (1) Integrated Site Model; (2) Unsaturated Zone Flow and Transport; (3) Near Field Environment; (4) Engineered Barrier System Degradation, Flow, and Transport; (5) Waste Package Degradation; (6) Waste Form Degradation; (7) Saturated Zone Flow and Transport; (8) Biosphere; and (9) Disruptive Events. Analysis/Model Reports (AMRs) contain the more detailed technical information used to support TSPA and the PMRs. The AMRs consists of data, analyses, models, software, and supporting documentation that will be used to defend the applicability of each process model for evaluating the postclosure performance of the potential Yucca Mountain repository system. This documentation will ensure the traceability of information from its source through its ultimate use in the TSPA-Site Recommendation (SR) and in the National Environmental Policy Act (NEPA) analysis processes. The objective of the Biosphere PMR is to summarize (1) the development of the biosphere model, and (2) the Biosphere Dose Conversion Factors (BDCFs) developed for use in TSPA. The Biosphere PMR does not present or summarize estimates of potential radiation doses to human receptors. Dose calculations are performed as part of TSPA and will be presented in the TSPA documentation. The biosphere model is a component of the process to evaluate postclosure repository performance and regulatory compliance for a potential monitored geologic repository at Yucca Mountain, Nevada. The biosphere model describes those exposure pathways in the biosphere by which radionuclides released from a potential repository could reach a human receptor

  11. Super Boiler: Packed Media/Transport Membrane Boiler Development and Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Liss, William E; Cygan, David F

    2013-04-17

    up to 50% smaller in footprint, has a smaller diameter, and is up to 50% lower in weight, resulting in very compact design with reduced material cost and labor costs, while requiring less boiler room floor space. For enhanced energy efficiency, the heat recovery system uses a transport membrane condenser (TMC), a humidifying air heater (HAH), and a split-stage economizer to extract maximum energy from the flue gas. The TMC is a new innovation that pulls a major portion of water vapor produced by the combustion process from the flue gases along with its sensible and latent heat. This results in nearly 100% transfer of heat to the boiler feed water. The HAH improves the effectiveness of the TMC, particularly in steam systems that do not have a large amount of cold makeup water. In addition, the HAH humidifies the combustion air to reduce NOx formation. The split-stage economizer preheats boiler feed water in the same way as a conventional economizer, but extracts more heat by working in tandem with the TMC and HAH to reduce flue gas temperature. These components are designed to work synergistically to achieve energy efficiencies of 92-94% which is 10-15% higher than today's typical firetube boilers.

  12. Central heating: fossil-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Blazek, C.F.; Baker, N.R.; Tison, R.R.

    1979-05-01

    This evaluation provides performance and cost data for fossil-fuel-fired steam boilers, hot-water generators, and thermal fluid generators currently available from manufacturers. Advanced-technology fluidized-bed boilers also are covered. Performance characteristics investigated include unit efficiencies, turndown capacity, and pollution requirements. Costs are tabulated for equipment and installation of both field-erected and packaged units. The information compiled in this evaluation will assist in the process of selecting energy-conversion units required for industrial, commercial, and residential applications.

  13. Transients in a circulating fluidized bed boiler

    Science.gov (United States)

    Baskakov, A. P.; Munts, V. A.; Pavlyuk, E. Yu.

    2013-11-01

    Transients in a circulating fluidized bed boiler firing biomass are considered. An attempt is made to describe transients with the use of concepts applied in the automatic control theory. The parameters calculated from an analysis of unsteady heat balance equations are compared with the experimental data obtained in the 12-MW boiler of the Chalmers University of Technology. It is demonstrated that these equations describe the transient modes of operation with good accuracy. Dependences for calculating the time constants of unsteady processes are obtained.

  14. Foam process models.

    Energy Technology Data Exchange (ETDEWEB)

    Moffat, Harry K.; Noble, David R.; Baer, Thomas A. (Procter & Gamble Co., West Chester, OH); Adolf, Douglas Brian; Rao, Rekha Ranjana; Mondy, Lisa Ann

    2008-09-01

    In this report, we summarize our work on developing a production level foam processing computational model suitable for predicting the self-expansion of foam in complex geometries. The model is based on a finite element representation of the equations of motion, with the movement of the free surface represented using the level set method, and has been implemented in SIERRA/ARIA. An empirically based time- and temperature-dependent density model is used to encapsulate the complex physics of foam nucleation and growth in a numerically tractable model. The change in density with time is at the heart of the foam self-expansion as it creates the motion of the foam. This continuum-level model uses an homogenized description of foam, which does not include the gas explicitly. Results from the model are compared to temperature-instrumented flow visualization experiments giving the location of the foam front as a function of time for our EFAR model system.

  15. Numerical simulation on the combustion process in a BFG fired boiler%全燃高炉煤气锅炉炉内燃烧过程的数值模拟

    Institute of Scientific and Technical Information of China (English)

    李丽丽; 谢安国; 曲超

    2011-01-01

    以鞍钢股份公司220t/h全燃高炉煤气锅炉为研究对象,利用CFD软件,对全燃高炉煤气锅炉炉内的燃烧过程进行模拟.得出锅炉炉内的速度场、温度场及NO,的排放量;并分析缩腰形炉膛及对冲布置的燃烧器对炉内燃烧过程的影响.模拟结果可为同类锅炉的优化设计、合理运行提供理论指导.%A 220 t / h BFG fired boiler of Angang Steel Company Limited is researched by using CFD software to simulate the combustion process of BFG fired boiler.The velocity field and temperature field is obtained, furthermore the influence that waist shape furnace and opposed layout combustor impact on the combustion process in furnace.And a theoretical guidance is provided to optimal design and reasonable operation of similar boiler.

  16. Optimizing the integrated design of boilers - simulation

    DEFF Research Database (Denmark)

    Sørensen, Kim; Karstensen, Claus M. S.; Condra, Thomas Joseph

    2004-01-01

    .) it is important to see the 3 components as an integrated unit and optimize these as such. This means that the burner must be designed and optimized exactly to the pressure part where it is utilized, the control system must have a conguration optimal for the pressure part and burner where it is utilized etc....... Traditionally boiler control systems have been designed in a rather simple manner consisting of a feed water controller and a pressure controller; two controllers which, in principle, operated without any interaction - for more details on boiler control see [4]. During the last year Aalborg Industries A/S has...... that are difcult to estimate/calculate have (on the basis of the tests) been determined by means of a least-square data tting, the minimums have been found by means of a Gauss-Newton algorithm and physically veried afterwards. The dynamic boiler model will be applied for developing controllers and adapting...

  17. 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

  18. Refactoring Process Models in Large Process Repositories.

    NARCIS (Netherlands)

    Weber, B.; Reichert, M.U.

    2008-01-01

    With the increasing adoption of process-aware information systems (PAIS), large process model repositories have emerged. Over time respective models have to be re-aligned to the real-world business processes through customization or adaptation. This bears the risk that model redundancies are introdu

  19. Refactoring Process Models in Large Process Repositories.

    NARCIS (Netherlands)

    Weber, B.; Reichert, M.U.

    With the increasing adoption of process-aware information systems (PAIS), large process model repositories have emerged. Over time respective models have to be re-aligned to the real-world business processes through customization or adaptation. This bears the risk that model redundancies are

  20. A comprehensive model for CFB boilers testing at two coal-fired power plants; Ein Gesamtmodell fuer ZWS-Dampferzeuger im Test an zwei Kohlekraftwerken

    Energy Technology Data Exchange (ETDEWEB)

    Fett, F.N. [Siegen Univ. (Gesamthochschule) (Germany); Schoeler, J. [Siegen Univ. (Gesamthochschule) (Germany); Edelmann, H. [Siegen Univ. (Gesamthochschule) (Germany); Peters, R. [Lurgi AG, Frankfurt am Main (Germany); Juergens, B. [Bayer AG, Leverkusen (Germany); Jahn, P. [Energie-Anlagen Berlin GmbH (Germany)

    1992-12-31

    A comprehensive model for the numerical simulation of the steady and unsteady-state operation of steam-raising units with CFB furnaces was developed. The mathematical model consists of two linked modules for the furnace and the water-/steam circuit. The model for the CFB furnace includes the plant components like combustion chamber, cyclone, fluidized bed heat exchanger and convective pass and is based on balance equations for mass and energy completed by empirical model formulations. In detail, the elements hydrodynamics, devolatilization and coal combustion including the particle size distribution of the coal as well as the essential mechanisms of formation and reduction of the pollutants CO, NO and SO{sub 2} are considered. To characterize the water-/steam circuit, the unsteady-state balance equations for mass, momentum and energy are drawn up. The linkage to the model for the CFB furnace results mainly from an unsteady-state equation for the heat flux through the walls. The verification of the comprehensive model refers to measurements of operating data carried out at the fluidzed bed boiler 1 of the Bayer AG, Leverkusen, and the Moabit Combined Heating and Power Plant of BEWAG, Berlin. In detail, a comparison of experimentally determined and calculated operating data for steady-state operation for the parameters furnace load, combustion temperature as well as air excess and for unsteady operation without control for abrupt change of fuel-, primary air- and feedwater mass flux as well as of arrow valve position. Beyond that by including the main control units it was possible to simulate the control behaviour for normal load change processes, too. The comparison between calculation and measurement shows good agreement for both steady-state- and transient process behaviour. (orig./GL) [Deutsch] Das mathematische Modell besteht aus gekoppelten Modulen fuer die Feuerung und die Wasser-Dampfseite. Die Modellierung der ZWS-Feuerung umfasst die Anlagenteile

  1. Optimising boiler performance.

    Science.gov (United States)

    Mayoh, Paul

    2009-01-01

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

  2. Boiler control using on-line determination of moisture content for incoming fuel; Forskning kring pannstyrning med on-line fukthaltsmaetning paa biobraensle

    Energy Technology Data Exchange (ETDEWEB)

    Avelin, Anders; Dahlquist, Erik; Moden, Per Erik

    2008-10-15

    Incoming fuels to the biomass fueled boiler are the main source for uncertainties in the combustion process. Fuel quality has large impact on the combustion and the heat transfer in the boiler. There are several possibilities to control the boiler when the bed temperature varies. Flue gas recirculation is one of the variables used for control of the bed temperature in the boiler. Another parameter to use for controlling the bed temperature is to adjust the humidification of the combustion air. The parameter with the major influence on the bed temperature is the amount of primary air. These three parameters are all used as control variables for control of the bed temperature. One part of the study has been to investigate how much and how fast each parameter influences bed temperature and how the information of the moisture content in the incoming fuel can be used for feed-forward information for controlling bed temperature. At the reception terminal all the incoming deliveries are registered with quality and moisture content. This study has also investigated how to use the information about the moisture content of incoming fuel, based on NIR measurements on the fuel transported in to the boiler, and the fluctuation of the bed temperature. Another question is how to connect this information for the bed control. This part of the study is used to evaluate if the information to the operators about the moisture content from the NIR has affect on the variation of the bed temperature. A process model has been developed of the Bubbling Fluidised Bed boiler (BFB) that is one of the boilers at the power plant in Eskilstuna. The model has been used to analyze the process. Process models have become more common and important in the heat and power industry. Nowadays process models are used for training of the staff in simulators of the real plant and for offline tests of control systems

  3. Transfer Function Modeling Method of Bed Temperature Based on Swarm Intelligence Algorithm in Circulating Fluidized Bed Boiler%循环流化床锅炉床温的传递函数智能建模方法

    Institute of Scientific and Technical Information of China (English)

    王利杰; 孙明; 程希; 殷立国; 孙剑

    2013-01-01

    通过研究循环流化床锅炉燃烧系统的机理和非参数建模方法,基于对循环流化态燃烧机理的认知,给出模型辨识的数据选择标准;挖掘机组运行的历史数据,提出了利用群体智能寻优算法进行燃料量与床温之间传递函数的参数辨识方法,并给出了快速仿真的公式以及一类单输入单输出系统的辨识结果和验证方法。所建立的传递函数模型完全能够表征具体某台循环流化床锅炉热工特性,为后续的控制逻辑和控制器的优化提供了数学依据。%This paper summarized two methods which include mechanism and non-parametric modeling in the cir-culating fluidized bed ( CFB) boiler's combustion system. Based on the understanding of combustion principle of circulating fluidized state, the criterion of data selection was given. By mining the historical datas of unit operation, a method of identifying undetermined parameters of the transfer function between fuel and bed temperature using the swarm intelligence optimizing algorithms was presented. Then, the rapid simulation formulas of thermal process and identification result and validation method of a class of single-input single-output system were given. Transfer func-tion which was established by this method can entirely represent the thermal characteristics of CFB boiler and pro-vide a mathematical basis for subsequent control logic or parameter's optimization of controller.

  4. Least Square Fast Learning Network for modeling the combustion efficiency of a 300WM coal-fired boiler.

    Science.gov (United States)

    Li, Guoqiang; Niu, Peifeng; Wang, Huaibao; Liu, Yongchao

    2014-03-01

    This paper presents a novel artificial neural network with a very fast learning speed, all of whose weights and biases are determined by the twice Least Square method, so it is called Least Square Fast Learning Network (LSFLN). In addition, there is another difference from conventional neural networks, which is that the output neurons of LSFLN not only receive the information from the hidden layer neurons, but also receive the external information itself directly from the input neurons. In order to test the validity of LSFLN, it is applied to 6 classical regression applications, and also employed to build the functional relation between the combustion efficiency and operating parameters of a 300WM coal-fired boiler. Experimental results show that, compared with other methods, LSFLN with very less hidden neurons could achieve much better regression precision and generalization ability at a much faster learning speed.

  5. 40 CFR Table 4 to Subpart Ddddd of... - Operating Limits for Boilers and Process Heaters With Hydrogen Chloride Emission Limits

    Science.gov (United States)

    2010-07-01

    ... compliance with the applicable emission limit for hydrogen chloride. 2. Dry scrubber control Maintain the... Process Heaters With Hydrogen Chloride Emission Limits 4 Table 4 to Subpart DDDDD of Part 63 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL EMISSION...

  6. Demand-based maintenance and operators support based on process models; Behovsstyrt underhaall och operatoersstoed baserat paa process modeller

    Energy Technology Data Exchange (ETDEWEB)

    Dahlquist, Erik; Widarsson, Bjoern; Tomas-Aparicio, Elena

    2012-02-15

    There is a strong demand for systems that can give early warnings on upcoming problems in process performance or sensor measurements. In this project we have developed and implemented such a system on-line. The goal with the system is to give warnings about both faults needing urgent actions, as well giving advice on roughly when service may be needed for specific functions. The use of process simulation models on-line can offer a significant tool for operators and process engineers to analyse the performance of the process and make the most correct and fastest decision when problems arise. In this project physical simulation models are used in combination with decision support tools. By using a physical model it is possible to compare the measured data to the data obtained from the simulation and give these deviations as input to a decision support tool with Bayesian Networks (BN) that will result in information about the probability for wrong measurement in the instruments, process problems and maintenance needs. The application has been implemented in a CFB boiler at Maelarenergi AB. After tuning the model the system has been used online during September - October 2010 and May - October 2011, showing that the system is working on-line with respect to running the simulation model but with batch runs with respect to the BN. Examples have been made for several variables where trends of the deviation between simulation results and measured data have been used as input to a BN, where the probability for different faults has been calculated. Combustion up in the separator/cyclones has been detected several times, problems with fuel feed on both sides of the boiler as well. A moisture sensor not functioning as it should and suspected malfunctioning temperature meters as well. Deeper investigations of the true cause of problems have been used as input to tune the BN

  7. Establishing an energy efficiency recommendation for commercial boilers

    Energy Technology Data Exchange (ETDEWEB)

    Ware, Michelle J.

    2000-08-01

    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.

  8. Narrow gap HST welding process and its application to candidate pipe material for 700 C USC boiler component

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Gang; Sato, Takashi; Fukuda, Yuji [Babcock-Hitachi K.K., Hiroshima (Japan). Kure Research Lab.; Mitsuhata, Koichi [Babcock-Hitachi K.K., Hiroshima (Japan). Kure Div.

    2008-07-01

    Increasing steam temperature and pressure conditions of 700 C USC (Ultra Super Critical) power plants under consideration require the adoption of Ni-based alloys. One of the most crucial issues for the application of 700 C USC power plants is the establishment of welding technology for the thick-walled components. This paper reports the research results on the practicability of candidate material for the thickwalled components. The weld test was conducted on Ni-based Alloy617 (52Ni-22Cr- 13Co-9Mo-Ti-Al) by using the narrow gap HST (Hot wire Switching TIG) welding process developed by Babcock-Hitachi K.K with the matching filler wire of Alloy617. The weldability and strength properties of weld joint were examined. The sound weld joint was achieved. The advantages of narrow gap HST welding process for the thick-walled components of Ni-based alloy were discussed from the viewpoints of weld metal chemical composition and creep rupture strength. Due to the good shielding effect, the melting loss of alloy elements in the weld consumable during the narrow gap HST welding procedure was suppressed successfully. The narrow gap HST weld joint showed comparable strength with the parent metal. (orig.)

  9. 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...

  10. Effects of Non Process Elements in the chemical recovery system of a kraft pulp mill from the incineration in the recovery boiler of biological sludge; Effekter av PFG vid indunstning och foerbraenning av bioslam i ett massabruks sodapanna

    Energy Technology Data Exchange (ETDEWEB)

    Dahlbom, Johan

    2003-01-01

    The purpose of this project was to investigate the effects of incineration of biological sludge in the recovery boiler of a Swedish Kraft pulp mill, StoraEnso Pulp AB Skutskaers Bruk, which has practiced incineration of sludge in the recovery boiler during the last two years. The following aspects of the technique were investigated: Experience from operation of incineration of biological sludge in the recovery boiler; The content of Non-Process Elements (NPE) in process flows and evaluate the risks of incrustations in the system; The build-up of NPE in the chemicals recovery system and the estimated increase in make-up lime demand; and Technical risks for mills with different process equipment. This study comprises the following NPE: aluminium, silicon, phosphorus, magnesium, calcium, chloride, iron, manganese, potassium, copper, and nitrogen. The operational experience from the system for hydrolysis of the biological sludge and evaporation/incineration in the recovery boiler is excellent. The handling of the sludge takes place in a closed system that demands little supervision and maintenance. Overall, the mill has not seen any negative effects that can be explained by increased intake of NPEs to the chemical recovery system. Aluminium can lead to troublesome incrustations of sodium-aluminium-silicates on the heat surfaces in the evaporation plant. An effective elimination of aluminium by the green liquor dreg is obtained with the double salt hydrotalcite if the quotient Mg/Al is kept higher than 4-5 in the black liquor. The need for make-up lime has increased due to the build-up of phosphorus in the lime. Depending on the level of make-up lime the need will increase 2-5 kg/ t{sub 90} at a price of 2-5 kr/t{sub 90}. If a higher level of phosphorus is accepted instead of increasing lime make-up the running costs will be somewhat higher, 0,5-1 kr/t{sub 90} due to increased ballast. NO{sub x} in the flue gases from the recovery boiler has not increased since the

  11. 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)

  12. Optimal scheduling of sootblowers in power plant boilers

    Science.gov (United States)

    Vasquez-Urbano, Pedro Manuel

    1997-11-01

    Burning coal or other fossil fuels in a utility boiler fouls the surfaces of its heat exchangers with ash and soot residues. These deposits affect the performance of the power plant since they reduce heat transfer from the combustion gases to the water or steam. Fouling can be removed during the operation of the plant with the use of lances, called sootblowers, that direct high-pressure air or steam onto the fouled surfaces. Sootblowing operations are key to plant efficiency and boiler maintenance, but they also incur operating costs. A utility boiler may have a hundred or so sootblowers placed in fixed locations. Deciding which of these should be used at any moment is complicated by the lack of instrumentation that can monitor fouling levels. This dissertation studies the optimization problem of scheduling sootblowing activities at a utility plant. The objective is to develop an optimization approach to determine which sootblowers should be activated at any moment in order to maximize plant efficiency. To accomplish this, three issues are addressed. First, models are developed that can estimate fouling conditions indirectly during plant operation using commonly available data. The approach used relies on a sequential application of linear regression fits. Secondly, autoregressive exogenous (ARX) models are used to describe the dynamics of the fouling process and to estimate the consequences of fouling on plant efficiency. All the foregoing empirical models are developed using data from a power plant. Finally, using the empirical models, an optimization model is formulated for the sootblowing scheduling problem and different optimization approaches that combine nonlinear programming with heuristics methods are investigated for its solution. The applicability of dynamic programming to this optimization problem is also explored.

  13. 基于果蝇优化算法的锅炉高效率低N Ox 燃烧建模%Fruit fly optimization algorithm based high efficiency and low NOx combustion modeling for a boiler

    Institute of Scientific and Technical Information of China (English)

    张振星; 孙保民; 信晶

    2014-01-01

    In order to control NOx emissions and enhance boiler efficiency in coal-fired boilers,the thermal operating data from an ultra-supercritical 1000MW unit boiler were analyzed.On the basis of the support vector regression machine (SVM),the fruit fly optimization algorithm (FOA)was applied to optimize the penalty parameter C,kernel parameter g and insensitive loss coefficient of the model.Then,the FOA-SVM model was established to predict the NOx emissions and boiler efficiency,and the performance of this model was compared with that of the GA-SVM model optimized by genetic algorithm (GA).The results show the FOA-SVM model has better prediction accuracy and generalization capability,of which the maximum aver-age relative error of testing set lies in the NOx emissions model,which is only 3 .5 9%.The above models can predict the NOx emissions and boiler efficiency accurately,so they are very suitable for on-line modeling prediction,which provides a good model foundation for further optimization operation of large capacity boilers.%为了控制燃煤锅炉的NOx 排放量并提高锅炉效率,对某超超临界1000 MW机组锅炉的热态运行数据进行分析,基于支持向量回归机(SVM),建立了 NOx 排放和锅炉热效率的 FOA-SVM模型,采用果蝇优化算法(FOA)对模型中的惩罚因子C、核函数参数g和不敏感损失系数ε这3个参数寻优,并与遗传算法(GA)优化参数的预测模型进行比较.结果表明,FOA-SVM模型的预测精度更高,泛化能力更强,其中误差最大的 NOx 排放模型测试集数据的平均相对误差仅3.59%,能够精准地预测锅炉热效率和 N Ox 排放,适合于在线建模预测,为大容量锅炉的进一步优化运行提供了良好的模型基础.

  14. Transparent and Explicable Boiler Fouling Monitoring with Fuzzy Neural Newtwork

    Institute of Scientific and Technical Information of China (English)

    BinWu; You-TingShen

    1998-01-01

    Fouling on boiler beating surfaces is one of the important factors that damage boiler's economical performance and safety,with on-line monitoring of foiling states on boler heating surfaces,it is possible to optimize sootblower system,to visualize fouling states,to improve performance,as well as to remedy the insufficiency of experiment research in boiler heating surface fouling process.New method based on Fuzzy Neural Network(FNN) is presented to monitor fouling states on boiler heating surfaces on-line.Compared with regular methods,since FNN's reasoning process is transparent and comprehensible,it is possible to explain and comprehend reasoning process,which makes the FNN based system perform as an additional operation consulting system.

  15. Numerical simulation of NOx formation in a cyclone-opposed coal-fired utility boiler

    Institute of Scientific and Technical Information of China (English)

    LI Fang-qin; REN Jian-xing; WEI Dun-song

    2005-01-01

    In this paper, FLUENT software was used to simulate the burning process in a utility boiler. Chose the kinetics/diffusion-limited as combustion model, two-compet-ingrates as devolatjlization model, RNG k-εmodel as viscous model, and PDF model as combustion turbulent flow model. Numerical calculation of NOx formation in a 330 MW cyclone-opposed coal-fired utility boiler with 32 double air registers was done. The distribution characteristics of temperature, NOx and oxygen concentration in furnace were studied. They were symmetrically distributed in furnace. In the combustion area, temperature and NOx concentration are high, while oxygen concentration is low. Temperature and NOx concentration are declined gradually along with furnace height, while oxygen concentration is raised. The higher the temperature is and the greater the excess air coefficient is, the more NOx formation.

  16. DOWNSCALE APPLICATION OF BOILER THERMAL CALCULATION APPROACH

    OpenAIRE

    Zelený, Zbynĕk; Hrdlička, Jan

    2016-01-01

    Commonly used thermal calculation methods are intended primarily for large scale boilers. Hot water small scale boilers, which are commonly used for home heating have many specifics, that distinguish them from large scale boilers especially steam boilers. This paper is focused on application of thermal calculation procedure that is designed for large scale boilers, on a small scale boiler for biomass combustion of load capacity 25 kW. Special issue solved here is influence of formation of dep...

  17. Modelación energética y operacional del sistema de agua de alimentar caldera de una central termoeléctrica; Modeling energetic and operational of the boiler feed water system of a power plant

    Directory of Open Access Journals (Sweden)

    Ernesto Miguel Solís Alemán

    2015-09-01

    Full Text Available Se propone un modelo combinado basado en la implementación paralela de dos aproximadores funcionales, utilizando una red neuronal del tipo (MLP y una regresión estadística, para la obtención de las características energéticas y de operación actual del Sistema de Agua de Alimentar Caldera (SAAC en una Central Termoeléctrica (CTE, en la cual se regula el flujo de agua a la caldera por variación de velocidad. La respuesta del modelo combinado se obtiene a partir de la suma ponderada de cada aproximador funcional. Dicho modelo es utilizado para relacionar el consumo de corriente y la posición del variador de velocidad, en función de la presión de descarga y el flujo entregado por cada bomba del SAAC. Para el ajuste de los modelos se utilizan mediciones almacenadas en el archivo histórico del sistema SCADA, donde se aplica un método de procesamiento de datos para eliminar ruidos que pueden afectar el ajuste de los modelos propuestos.Is proposed a combined model based on the parallel implementation of two functional approximators, using a neural network of the type (MLP and a statistical regression to obtain the actual energetic and operation characteristics of the Boiler Feed Water System (BFWS in a Power Plant, in which the water flow to the boiler is controlled by variation speed. The response of the combined model is obtained from the weighted sum of each functional approximator. This model is used to relate the current consumption and the position of the speed variator, in function of the discharge pressure and flow delivered by each pump of the BFWS. For the fit of the models is used save measurements of the historical file of the SCADA system, where is applied a data processing method to eliminating noise that can affect the fit of the models proposed.

  18. Multivariate (alarms) process control for reduced risk for bed agglomeration/defluidisation in FB boilers; Multivariat (alarm) processoevervakning foer minskad risk foer baeddagglomerering/defluidisering i FB-anlaeggningar

    Energy Technology Data Exchange (ETDEWEB)

    Oehman, M. [ETC, Piteaa (Sweden); Hoekfors, C. [Sigma iSoft AB, Piteaa (Sweden); Nordin, A. [Umeaa Univ. (Sweden). Dept. of Chemistry; Lundberg, L. [Skellefteaa Kraft AB, Skellefteaa (Sweden); Nordsvahn, L. [ETC, Piteaa (Sweden)

    2002-01-01

    Ash-related operational problems are one of the most common process-related disturbances during biomass combustion. Bed agglomeration (sintering) is especially problematic during fluid bed combustion. In most severe cases, agglomeration and blocking of the return-valves in CFB-plants could result in unplanned plant shut down. It would therefore be of considerable interest to find a method, which could predict initial problems in such a god time before a outset problem so that measure for prevention could be taken before it is to late. With traditional process control systems this has been difficult or impossible. The time from initial agglomeration of the bed material particles to a total defluidisation of the bed could be very short. It is therefore often too late to solve the problem when the operational personals have discovered that something is going on. The aim of the present work was therefore, in a full-scale FB-plant, to illustrate the benefits of multivariate process control and multivariate alarms for reducing the risk for agglomeration in the bed and/or in the return-valves, i.e. unplanned plant shut down. One biomass fired CFB-plant has participated in the project (Skellefteaa Kraft AB). Previous agglomeration experiences in this plant have been located to the cyclone and the return valves. Operational-parameters such as temperatures, pressures and gas-composition etc. were continuously taken out from the traditional process-system for external multivariate treatment by principal component analysis (PCA). Simultaneously, a diary was kept with characterisation of experienced ash related problems by the operational personal. The produced PCA-models have then been used for indicating deviations from 'normal' operation (multivariate alarms) for executed data taken before and in connection with the operational stop, caused by clogging of the cyclone-leg, during December 2000. The results strongly indicated that the produced PCA-model could predict

  19. Modular process modeling for OPC

    Science.gov (United States)

    Keck, M. C.; Bodendorf, C.; Schmidtling, T.; Schlief, R.; Wildfeuer, R.; Zumpe, S.; Niehoff, M.

    2007-03-01

    Modular OPC modeling, describing mask, optics, resist and etch processes separately is an approach to keep efforts for OPC manageable. By exchanging single modules of a modular OPC model, a fast response to process changes during process development is possible. At the same time efforts can be reduced, since only single modular process steps have to be re-characterized as input for OPC modeling as the process is adjusted and optimized. Commercially available OPC tools for full chip processing typically make use of semi-empirical models. The goal of our work is to investigate to what extent these OPC tools can be applied for modeling of single process steps as separate modules. For an advanced gate level process we analyze the modeling accuracy over different process conditions (focus and dose) when combining models for each process step - optics, resist and etch - for differing single processes to a model describing the total process.

  20. Application of a stochastic modelling framework to characterize the influence of different oxide scales on the solid particle erosion behaviour of boiler grade steel

    Indian Academy of Sciences (India)

    S K Das

    2011-08-01

    An earlier developed stochastic model has been applied to describe the relative rate of material loss from the steel surface subjected to simultaneous action of high temperature oxidation involving multiple oxides and mechanical erosion. Different oxide scale growths, namely, nickel, iron and chromium have been treated deterministically and erosion is described using a literature based probabilistic framework. Oxidation is described with a power law (parabolic) approach to quantify the rate of growth of all the three oxide scales. In consonance with the published model, erosion is treated using a probabilistic methodology as spatially random phenomena on the oxide surface. The concept of ‘erosion footprint’ has been incorporated in the present model to characterize the erosion-induced damage on the steel surface. The model has been applied to predict the relative material loss as a function of time resulted from erosion–oxidation interaction pertaining to nickel, iron and chromium oxides in dimensionless form. This investigation is expected to provide a quantitative understanding of relative material loss due to solid particle erosion for oxide scales, (composed of multiple oxides) formed on the steel components of coal-fired boilers.

  1. WASTE HEAT RECOVERY FROM BOILER OF LARGE-SCALE TEXTILE INDUSTRY

    OpenAIRE

    Prateep Pattanapunt; Kanokorn Hussaro; Tika Bunnakand; Sombat Teekasap

    2013-01-01

    Many industrial heating processes generate waste energy in textile industry; especially exhaust gas from the boiler at the same time reducing global warming. Therefore, this article will present a study the way to recovery heat waste from boiler exhaust gas by mean of shell and tube heat exchanger. Exhaust gas from boiler dyeing process, which carries a large amount of heat, energy consumptions could be decrease by using of waste-heat recovery systems. In this study, using ANASYS simulation p...

  2. Influence of process parameters on coal combustion performance. Review, experiments and engineering modeling

    Energy Technology Data Exchange (ETDEWEB)

    Lans, R.P. van der

    1997-04-01

    The objective of this study is to improve the understanding of nitrogen oxide formation and carbon burnout during the combustion of pulverized coal, and to contribute to addressing the potential of chemical engineering models for the prediction of furnace temperatures, NO emissions and the amount of carbon in ash. To this purpose, the effect of coal quality on NO and burnout has been investigated experimentally, a radiation heat balance has been developed based on a simple chemical engineering methodology, and a mixing study has been conducted in order to describe the near burner macro mixing in terms of a reactor configuration. The influence of coal type and process conditions on NO formation and carbon burnout has been investigated experimentally in a 400 MW{sub e} corner fired boiler with over fire air, a 350 MW{sub e} opposed fired boiler, and in a 160 kW{sub t} pilot scale test rig. Three different coals were fired in each of the furnaces as part of the activities in group 3 of the European Union JOULE 2 Extension project `Atmospheric Pressure Combustion of Pulverized Coal and Coal Based Blends for Power Generation`. On the pilot scale test both single stage and air staged tests were performed. A simple, one-dimensional combustion and radiation heat transfer model has been developed for the furnace of full scale boilers. The model has been applied to the two boilers mentioned above, and is validated against measured temperatures and carbon in ash concentrations. A mixing study has been performed in order to initiate an investigation of the potential of chemical engineering models to predict NO from pulverized fuel burners. (EG) 11 refs.

  3. Three-dimensional computer simulation for combustion and NO{sub x} emission in a grate fired boiler at Baeckhamars, Sweden. Technical report[(Baeckhammars Bruk)

    Energy Technology Data Exchange (ETDEWEB)

    Dong Wei [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Metallurgy

    2000-05-01

    This report describes the fundament of mathematical modeling for the grate fired boilers in Part A, and presents the results from the numerical simulations for the flow pattern, combustion and NO{sub x} emission in the Baeckhammars grate fired boiler in Part B. The simulated boiler is equipped with a new secondary air supply system called Ecotube. The objective of this project is to develop and experimentally verify tools for computer simulations of solid biomass fuel combustion processes in a grate fired boiler. The work focuses on the numerical simulation using CFD technique and development of a NO{sub x} post processor. The unstructured mesh technique also has been used to discretize the boiler. An unstructured grid with total 284399 tetrahedral cells describes the three dimensional geometry and is used for flow field and combustion simulations. In order to simulate the combustion process in the boiler, a simplified grate bed model -- black-box bed model is used, which is based on the balance analysis of mass and energy on the grate bed and needless to consider any detailed and very difficult dynamic processes which have not been valuable by mathematical modeling on the grate bed yet. Therefore, it is quite convenient for industrial applications. In this work, both the cyanide route and the ammonia route for modeling the fuel containing nitrogen NO{sub x} are developed, and the former has been used to predict the NO generation in Baeckhammars bark boiler. Two 3D cases corresponding to 15 MW and 11 MW output thermal power respectively are simulated in detail. Results show that a new air supply system called Ecotube gives a considerably more uniform velocity, temperature and concentration distribution from the secondary air tubes to the upper part of the furnace. The upper furnace works almost as a 'plug flow reactor' which gives sufficient residence time for CO conversion and low NO{sub x} emission. The calculations of flow and mixing patterns in the

  4. Boiler for ships; Hakuyo boira

    Energy Technology Data Exchange (ETDEWEB)

    Shimoda, F. [Mitsubishi Heavy Industries, Ltd., Tokyo (Japan)

    1999-07-20

    In this paper, production and technology trend of boiler for ships in 1998 are described. The actual results of main boiler are as follows. As the main boiler for LNG ships, 4 boilers produced by Mitsui Engineering and Shipbuilding for Qatar Project, 8 produced by Kawasaki Heavy Industries for South Korea and 10 produced by Mitsubishi Heavy Industries for domestic use and South Korea. 1998 was an active year for the main boiler for ships. The auxiliary boiler of steam pressure of 16k to 25k equipping for tanker ships was 115 (4,441t/h of steam quantity in total), it greatly increased in comparison with 88 (3,172t/h) produced in the proceeding year. Donkey boilers of steam pressure of 6k to 10k equipping for container ships and bulk cargo was 147 (672t/h), and it substantially decreased in comparison with 274 (693t/h) of the proceeding year, but capacity per boiler increased. The gas exhaust economizer for turbo power generation plants was 6 produced for VLCC. (NEDO)

  5. Boiler design for fuel economy

    Energy Technology Data Exchange (ETDEWEB)

    Ramaswamy, M.P.; Sastry, C.V.R.L.; Tharakraj, M.

    1980-03-01

    In view of the limited fuel resources and ever increasing demand, Bharat Heavy Electricals, Ltd. (BHEL), as the leading boiler manufacturer, always endeavours to effect fuel economy in all possible avenues, leaving no stone unturned in this effort. This paper outlines some of the major efforts of BHEL in the area of boiler design to effect fuel economy.

  6. Hybrid Modeling Optimization of Thermal Efficiency and NOx Emission of Utility Boiler%电站锅炉热效率和NOx排放混合建模与优化

    Institute of Scientific and Technical Information of China (English)

    吕玉坤; 彭鑫; 赵锴

    2011-01-01

    Increasing thermal efficiency of utility boilers and reducing pollutant emission are both important for saving energy and protecting environment. The artificial intelligence method is widely used in boiler combustion optimization. Based on the test data of boiler combustion adjustment in a 300 MW power plant, a model of the boiler combustion system was established by using BP neural network targeting at boiler efficiency and NOx emission. The present model was optimized with the genetic algorithms to improve the training and prediction accuracy. The average prediction error declines from 0.22% to 0.06% for boiler efficiency and from 3.5% to 0.15% for NOx emission concentration. And based on global optimization with genetic algorithm method, the multi-objective optimization was transformed to a single objective optimization with weight coefficients. The results show that the present method can optimize the boiler efficiency and NO~ emission according to practical requirements, and the optimization level depends on each weight coefficient. Thus, the corresponding boiler operation control parameters could be obtained, which can provide guidance for power plant boiler optimal operation.%提高电站锅炉热效率和降低污染物排放对于节约能源和保护环境具有重要意义。人工智能方法在优化锅炉燃烧方面有广泛的应用。该文以某300MW电站锅炉燃烧调整试验数据为基础,采用BP神经网络建立以锅炉效率和NOx排放为目标的锅炉燃烧系统模型,利用遗传算法对模型进行优化,使模型训练精度和预测精度大为提高,锅炉效率平均预测误差由0.22%降至0.06%,NOx排放浓度平均预测误差由3.5%降至0.15%。利用遗传算法进行全局寻优,并用权重系数法将多目标优化转化为单目标优化。结果表明,该方法可根据需要对锅炉效率和NOx排放进行优化,实际中需重点优化锅炉效率或者重点优化NOx排放时

  7. Boilers a practical reference

    CERN Document Server

    Rayaprolu, Kumar

    2012-01-01

    AAbrasion and Abrasion Index (see Wear)Absolute or Dynamic Viscosity (æ) (see Viscosity in Fluid Characteristics)Acid Cleaning (see Commissioning)Acid Rain (also see Air Pollution Emissions and Controls and Gas Cleaning)Acid Sludge (see Refuse Fuels from Refinery in Liquid Fuels)Acid Smuts (see Oil Ash)Acoustic Soot Blowers (see Sonic Horns)Acoustic Enclosure (see Noise Control)Acoustic Leak Detection SystemAdiabatic Flame Temperature (see Combustion)Aeroderivative (see Types of GTs in Turbines, Gas)Ageing of Boiler ComponentsAgro-Fuels and FiringAir Ducts (see Draught Plant)Air Flow Measureme

  8. 基于机制模型与数据驱动的超临界锅炉性能在线预测方法%Performance Online Prediction of Supercritical Boilers Based on Mechanism and Data-driven Model

    Institute of Scientific and Technical Information of China (English)

    仝营; 钟崴; 童水光

    2015-01-01

    The topology of the boiler heating system was described by the correlation matrix, and the mass conservation equations, energy conservation equations and momentum conservation equations of the flue gas, air and water flows were provided, as well as the solving method. Combined with the established algorithm model of the boiler heat exchanger components, the mechanistic model of the boiler heating system was obtained. Basing on the mechanism analysis and historical data, soft sensing models were established in order to achieve the measurement of the boiler thermal parameters not easily to be measured directly. The soft sensing results of data were as inputs of the mechanistic model of the boiler heating system to establish boiler performance analysis, calculation and prediction models. The browser/server architecture model was used to develop the utility boiler performance analysis and prediction system supporting online monitoring. Thermal performance of a supercritical power plant boiler was calculated and predicted. The results verify the validity of the model and method. And the steam temperature was controlled by spraying water according to the predicted value.%基于关联矩阵描述锅炉热力系统拓扑结构,给出锅炉烟气、空气和水流程的质量守恒方程、能量守恒方程和动量守恒方程及其求解方法;结合建立的锅炉换热部件算法模型,得到锅炉热力系统的机制模型。基于机制分析和历史数据建立软测量模型,实现对不易直接测量的锅炉热工参数的间接测量。将软测量结果数据再次作为锅炉热力系统机制模型的输入,从而建立锅炉性能分析计算和预测模型。在系统实现技术上,采用基于浏览器/服务器的架构模式,研发支持在线监测的电站锅炉性能分析与预测系统。对一台超临界电站锅炉的性能进行预测计算,验证文中模型和方法的有效性,并根据预测值,实现蒸汽温度的喷水减温控制。

  9. 锅炉-汽轮机组的协调控制器整定%Tuning of Coordinated Controllers for Boiler-turbine Units

    Institute of Scientific and Technical Information of China (English)

    房方; 谭文; 刘吉臻

    2005-01-01

    A simple two-by-two model for a boiler-turbine unit is derived in this paper, which can capture the essential dynamics of the typical process. The coordinated controller is designed based on this model. A PID control structure and a tuning procedure are proposed. The example shows that the method is easy to use and can achieve an acceptable performance.

  10. 基于MATLAB软件的蒸汽锅炉连续排污余热回收设计%Process Design of Waste Heat Recovery in Continuous Blowdown of Steam Boiler Based on MATLAB Software

    Institute of Scientific and Technical Information of China (English)

    刘舒佳; 关文吉; 刘伟; 冯圣红; 孙晓禹

    2016-01-01

    An energy-saving scheme is proposed to solve the waste heat and water resources in continuous blowdown of steam boiler. Matlab software is utilized to design calculation program for heat exchanger in heat recovery of steam boiler's continuous blowdown because of the complex problems in heat recovery design. Iterative methods are applied to obtain the heat gain of the deaerated water tank and softened water tank respectively. The heat exchange area of heat exchanger is calculated and investigated in different ways in the process of the waste heat recovery. The optimal plan for calculating heat exchange area is selected with comparison and analysis. The energy saving effect of the continuous waste heat recovery scheme for steam boiler is analyzed and calculated.%为解决蒸汽锅炉连续排污余热回收过程中废热及水资源浪费的问题提出一种节能方案.针对蒸汽锅炉连续排污余热回收过程中换热器设计计算较为复杂的问题,运用Matlab软件就蒸汽锅炉连续排污余热回收过程中换热器的设计计算编写程序,使用迭代的方式得出除氧水箱与软化水箱的分别得热量,探讨以不同的方式计算余热回收过程中换热器换热面积的问题;对比分析换热面积计算的2种方法,选取较优方案.分析计算提出的蒸汽锅炉连续排污余热回收方案的节能效果.

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

    Energy Technology Data Exchange (ETDEWEB)

    Uth, Joern

    2012-01-15

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Uth, Joern

    2010-08-15

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

  13. Boiler modification studies at Gerald Gentleman Staion Unit 1

    Energy Technology Data Exchange (ETDEWEB)

    Kettenacker, W.C. [Performance Engineering, Inc., Lewisville, TX (United States); Favinger, J.O. [Nebraska Public Power District, Southerland, NE (United States)

    1996-05-01

    For several years, Nebraska Public Power District`s (NPPD) Gerald Gentleman Station Unit 1 (GGS1) has experienced boiler problems. Specifically, Unit 1 has had difficulty achieving design main steam and reheat steam temperatures. In addition, the economizer exit gas temperature has been too high, and the reheat surface has become routinely fouled. To determine the cause of these problems and to find possible solutions, NPPD contracted with a boiler manufacturer to review results of a recent performance test on the boiler and offer possible solutions. Some of the solutions offered by the boiler manufacturer were unrealistic, while others offered some promise. In early 1994, NPPD and Performance Engineering, Inc. (PEI) reviewed the results of the boiler manufacturer using a PEPSE (Performance Evaluation of Power System Efficiencies) model originally developed by NPPD and later modified by PEI. In addition, solutions not offered by the boiler manufacturer were studied. Results of the PEPSE study showed that increases to the reheat and superheat surface areas would increase the steam temperatures to the design levels while decreasing the gas temperature leaving the economizer. However, the studies also showed that keeping the surfaces clean would produce the same effect as adding more area without the capital investment. The results of the PEPSE study on GGS1 are presented and solutions are offered. A discussion of the PEPSE model and modeling techniques used for this study are also presented.

  14. On Activity modelling in process modeling

    Directory of Open Access Journals (Sweden)

    Dorel Aiordachioaie

    2001-12-01

    Full Text Available The paper is looking to the dynamic feature of the meta-models of the process modelling process, the time. Some principles are considered and discussed as main dimensions of any modelling activity: the compatibility of the substances, the equipresence of phenomena and the solvability of the model. The activity models are considered and represented at meta-level.

  15. Applied studies in advanced boiler technology for Rankine cycle power systems

    Energy Technology Data Exchange (ETDEWEB)

    Paul, F.W.; Negreanu, M.J.

    1978-02-01

    A study is presented on a new rotational boiler design which has improved passive dynamic response and two-phase flow stability characteristics. A survey of small boiler manufacturers in the United States indicated that currently available designs are based on steady-state operating requirements rather than for dynamic performance. Recent work by EPA and ERDA which addressed boiler designs for mobile automotive Rankine cycle power systems showed that boilers of a monotube or multipass tube configuration design could be developed which were physically compact, but still were subject to the two-phase flow instability problem when coupled within an operating power system. The objectives of this work were to evaluate alternative boiler configurations which would improve boiler dynamic response and also have good two-phase liquid-vapor interface flow stability. The major physical design limitation of any boiler is the small external hot gas heat transfer coefficient. Such a low coefficient requires considerable design enhancements to increase the rate of energy transfer to the circulation system fluid. The rotational boiler is a physical design configuration which addresses this problem. The results of an analytic study using several mathematical model formulations showed that a rotational boiler could have a passive response time constant which was approximately one-half the magnitude for an equivalent single pass monotube boiler. An experimental prototype rotational boiler was designed, manufactured and tested, with the experimental results confirming that the experimental passive response time constants were comparable to the estimates from the analytic models. The experimental boiler operating in two-phase flow was found to be stable and responsive to external inputs. A rotational boiler configuration is a good alternative design configuration for small compact vapor generator designs based on fast transient passive response and two-phase flow stability.

  16. 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...

  17. 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... Ship's boilers. (a) Before work is performed in the fire, steam, or water spaces of a boiler where... dead boiler with the live system or systems shall be secured, blanked, and tagged indicating...

  18. 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,...

  19. 46 CFR 61.05-10 - Boilers in service.

    Science.gov (United States)

    2010-10-01

    ... 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... 46 Shipping 2 2010-10-01 2010-10-01 false Boilers in service. 61.05-10 Section 61.05-10...

  20. Energy Analysis of Baby Boiler for Steaming of Raw Cashew Nut Seeds

    OpenAIRE

    Atul Mohod; Y. P. Khandetod; S. H. Sengar; Shrirame, H. Y.

    2012-01-01

    The steaming of raw cashew seeds prior to shelling is adopted widely in small-scale cashew nut processing mills with the help of baby boiler. The wide variations in energy intensity of these mills reveal the scope for energy conservation. The baby boiler coupled with cooker commonly used for steaming of raw seeds was evaluated. The variation in steam pressure, temperature and operating time with respect to fuel was observed along with thermal efficiency of a boiler. The energy intensity to pr...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-12-31

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

  2. A comparison of fuzzy logic and cluster renewal approaches for heat transfer modeling in a 1296 t/h CFB boiler with low level of flue gas recirculation

    Science.gov (United States)

    Błaszczuk, Artur; Krzywański, Jarosław

    2017-03-01

    The interrelation between fuzzy logic and cluster renewal approaches for heat transfer modeling in a circulating fluidized bed (CFB) has been established based on a local furnace data. The furnace data have been measured in a 1296 t/h CFB boiler with low level of flue gas recirculation. In the present study, the bed temperature and suspension density were treated as experimental variables along the furnace height. The measured bed temperature and suspension density were varied in the range of 1131-1156 K and 1.93-6.32 kg/m3, respectively. Using the heat transfer coefficient for commercial CFB combustor, two empirical heat transfer correlation were developed in terms of important operating parameters including bed temperature and also suspension density. The fuzzy logic results were found to be in good agreement with the corresponding experimental heat transfer data obtained based on cluster renewal approach. The predicted bed-to-wall heat transfer coefficient covered a range of 109-241 W/(m2K) and 111-240 W/(m2K), for fuzzy logic and cluster renewal approach respectively. The divergence in calculated heat flux recovery along the furnace height between fuzzy logic and cluster renewal approach did not exceeded ±2%.

  3. Auditory processing models

    DEFF Research Database (Denmark)

    Dau, Torsten

    2008-01-01

    The Handbook of Signal Processing in Acoustics will compile the techniques and applications of signal processing as they are used in the many varied areas of Acoustics. The Handbook will emphasize the interdisciplinary nature of signal processing in acoustics. Each Section of the Handbook will pr...

  4. 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

  5. Model-free adaptive control of advanced power plants

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, George Shu-Xing; Mulkey, Steven L.; Wang, Qiang

    2015-08-18

    A novel 3-Input-3-Output (3.times.3) Model-Free Adaptive (MFA) controller with a set of artificial neural networks as part of the controller is introduced. A 3.times.3 MFA control system using the inventive 3.times.3 MFA controller is described to control key process variables including Power, Steam Throttle Pressure, and Steam Temperature of boiler-turbine-generator (BTG) units in conventional and advanced power plants. Those advanced power plants may comprise Once-Through Supercritical (OTSC) Boilers, Circulating Fluidized-Bed (CFB) Boilers, and Once-Through Supercritical Circulating Fluidized-Bed (OTSC CFB) Boilers.

  6. Model-free adaptive control of advanced power plants

    Science.gov (United States)

    Cheng, George Shu-Xing; Mulkey, Steven L.; Wang, Qiang

    2015-08-18

    A novel 3-Input-3-Output (3.times.3) Model-Free Adaptive (MFA) controller with a set of artificial neural networks as part of the controller is introduced. A 3.times.3 MFA control system using the inventive 3.times.3 MFA controller is described to control key process variables including Power, Steam Throttle Pressure, and Steam Temperature of boiler-turbine-generator (BTG) units in conventional and advanced power plants. Those advanced power plants may comprise Once-Through Supercritical (OTSC) Boilers, Circulating Fluidized-Bed (CFB) Boilers, and Once-Through Supercritical Circulating Fluidized-Bed (OTSC CFB) Boilers.

  7. GREAT Process Modeller user manual

    OpenAIRE

    Rueda, Urko; España, Sergio; Ruiz, Marcela

    2015-01-01

    This report contains instructions to install, uninstall and use GREAT Process Modeller, a tool that supports Communication Analysis, a communication-oriented business process modelling method. GREAT allows creating communicative event diagrams (i.e. business process models), specifying message structures (which describe the messages associated to each communicative event), and automatically generating a class diagram (representing the data model of an information system that would support suc...

  8. Corrosion of oil-fired boilers caused by sour combustion products of the sulfur contained in fuels

    Energy Technology Data Exchange (ETDEWEB)

    Koebel, M.; Elsener, M.

    1987-01-01

    A corrosion model helps to experimentally explain why industrial boilers are more susceptible to corrosion than smaller boilers and why vapour dew points are relevant to heating boilers while sulfuric acid dew points are relevant to steam boilers. Analyses are based on model verifications (measurement of critical boiler factors). Access is given to the sulfur trioxide measuring methods as well as to the respective tests of 30 actively operated boilers (sulfur oxide concentrations at burner outlets), the catalytic formation of sulfur oxides, and tests of the test stand boiler (sulfur oxide deposits). The paper concludes with a description of corrosion product analyses as such as well as with an account of the results obtained. Analyses and results (wet analysis, X-ray structure analysis, influence of temperatures, FeSO/sub 4/ x H/sub 2/O tracing) are presented in the form of eight brief statements. (HWJ)

  9. Recovery of Water from Boiler Flue Gas

    Energy Technology Data Exchange (ETDEWEB)

    Edward Levy; Harun Bilirgen; Kwangkook Jeong; Michael Kessen; Christopher Samuelson; Christopher Whitcombe

    2008-09-30

    This project dealt with use of condensing heat exchangers to recover water vapor from flue gas at coal-fired power plants. Pilot-scale heat transfer tests were performed to determine the relationship between flue gas moisture concentration, heat exchanger design and operating conditions, and water vapor condensation rate. The tests also determined the extent to which the condensation processes for water and acid vapors in flue gas can be made to occur separately in different heat transfer sections. The results showed flue gas water vapor condensed in the low temperature region of the heat exchanger system, with water capture efficiencies depending strongly on flue gas moisture content, cooling water inlet temperature, heat exchanger design and flue gas and cooling water flow rates. Sulfuric acid vapor condensed in both the high temperature and low temperature regions of the heat transfer apparatus, while hydrochloric and nitric acid vapors condensed with the water vapor in the low temperature region. Measurements made of flue gas mercury concentrations upstream and downstream of the heat exchangers showed a significant reduction in flue gas mercury concentration within the heat exchangers. A theoretical heat and mass transfer model was developed for predicting rates of heat transfer and water vapor condensation and comparisons were made with pilot scale measurements. Analyses were also carried out to estimate how much flue gas moisture it would be practical to recover from boiler flue gas and the magnitude of the heat rate improvements which could be made by recovering sensible and latent heat from flue gas.

  10. INNOVATION PROCESS MODELLING

    Directory of Open Access Journals (Sweden)

    JANUSZ K. GRABARA

    2011-01-01

    Full Text Available Modelling phenomena in accordance with the structural approach enables one to simplify the observed relations and to present the classification grounds. An example may be a model of organisational structure identifying the logical relations between particular units and presenting the division of authority, work.

  11. Green boilers; La chaudiere verte

    Energy Technology Data Exchange (ETDEWEB)

    Scrive, L.; Lebois, P.; Schlienger, M.; Moser, D. [Gaz de France (GDF), 75 - Paris (France)

    1997-12-31

    The ``green`` boiler was designed and developed by the Gaz de France and GEC Alsthom Stein Fasel partnership. It is a new make of steam boiler with smoke tubes from 4 to 15 MW. This range meets tow of the requirements guaranteed by the engineer: a NOx emission level lower than 100 mg/m{sup 3} (n) with 3% of oxygen and an combustion output of no less than 95 + 2% on n.v.c. A pilot operation was carried out by CNI Technologies in France. This 8.6 MW boiler was installed in June 1995 and performances checks were carried out by Apave Normandie in September 1995. This environmentally friendly boiler as well as the results obtained during the pilot operation are addressed in this article. (authors)

  12. 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.

  13. Study on purge gas generated in coke oven gas boilers mixing-firing process%焦炉气锅炉掺烧弛放气探讨

    Institute of Scientific and Technical Information of China (English)

    高翔

    2012-01-01

    It' s not an environmental friendly and economy way to discharged purge gas from methanol plant into the atmosphere. How to recycle methanol purge gas? The treatment of purge gas had been a general concern problem. The problem could be solved by incorpo- rating the decompression purge gas into boilers burning coke oven gas used as burning gas.%甲醇厂弛放气直接排人大气,既对环境产生污染,又无法实现经济价值。通过将弛放气减压掺入焦炉煤气中供锅炉燃烧使用的方法,可以解决弛放气的去向问题。

  14. Scandinavian baffle boiler design revisited

    Directory of Open Access Journals (Sweden)

    Stepanov Borivoj Lj.

    2015-01-01

    Full Text Available The aim of this paper is to examine whether the use of baffles in a combustion chamber, one of the well-known low-cost methods for the boiler performance improvement, can be enhanced. Modern day tools like computational fluid dynamics were not present at the time when these measures were invented, developed and successfully applied. The objective of this study is to determine the influence of location and length of a baffle in a furnace, for different mass flows, on gas residence time. The numerical simulations have been performed of a simple Scandinavian stove like furnace. The isothermal model is used, while air is used as a medium and turbulence is modeled by realizable k-epsilon model. The Lagrange particle tracking is used for the residence time distribution determination. The statistical analysis yielded the average residence time. The results of the computational fluid dynamics studies for different baffle positions, dimensions and flow rates show from up to 17% decrease to up to 13 % increase of residence time. The conclusion is that vertical position of the baffle is the most important factor, followed by the length of the baffle, while the least important showed to be the mass flow. [Projekat Ministarstva nauke Republike Srbije, br. III 43008: Development of methods, sensors and systems for monitoring of quality of water, air and land

  15. BPMN Impact on Process Modeling

    OpenAIRE

    Polak, Przemyslaw

    2013-01-01

    Recent years have seen huge rise in popularity of BPMN in the area of business process modeling, especially among business analysts. This notation has characteristics that distinguish it significantly from the previously popular process modeling notations, such as EPC. The article contains the analysis of some important characteristics of BPMN and provides author’s conclusions on the impact that the popularity and specificity of BPMN can have on the practice of process modeling. Author's obse...

  16. Factors controlling alkalisalt deposition in recovery boiler- release mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    McKeough, P.; Kylloenen, H.; Kurkela, M. [VTT Energy, Espoo (Finland). Process Technology Group

    1996-12-01

    As part of a cooperative effort to develop a model to describe the behaviour of inorganic compounds in kraft recovery boilers, an experimental investigation of the release of sulphur during black liquor pyrolysis has been undertaken. Previous to these studies, the mechanisms of sulphur release and the reasons for the observed effects of process conditions on sulphur release were very poorly understood. On the basis of the experimental results, the main reactions leading to sulphur release have been elucidated with a fair degree of certainty. Logical explanations for the variations of sulphur release with temperature and with liquor solids content have been proposed. The influence of pressure has been investigated in order to gain insights into the effects of mass transfer on the sulphur-release rate. In the near future, the research will be aimed at generating the kinetic data necessary for modelling the release of sulphur in the recovery furnace. (author)

  17. Radiolysis Process Model

    Energy Technology Data Exchange (ETDEWEB)

    Buck, Edgar C.; Wittman, Richard S.; Skomurski, Frances N.; Cantrell, Kirk J.; McNamara, Bruce K.; Soderquist, Chuck Z.

    2012-07-17

    Assessing the performance of spent (used) nuclear fuel in geological repository requires quantification of time-dependent phenomena that may influence its behavior on a time-scale up to millions of years. A high-level waste repository environment will be a dynamic redox system because of the time-dependent generation of radiolytic oxidants and reductants and the corrosion of Fe-bearing canister materials. One major difference between used fuel and natural analogues, including unirradiated UO2, is the intense radiolytic field. The radiation emitted by used fuel can produce radiolysis products in the presence of water vapor or a thin-film of water (including OH• and H• radicals, O2-, eaq, H2O2, H2, and O2) that may increase the waste form degradation rate and change radionuclide behavior. H2O2 is the dominant oxidant for spent nuclear fuel in an O2 depleted water environment, the most sensitive parameters have been identified with respect to predictions of a radiolysis model under typical conditions. As compared with the full model with about 100 reactions it was found that only 30-40 of the reactions are required to determine [H2O2] to one part in 10–5 and to preserve most of the predictions for major species. This allows a systematic approach for model simplification and offers guidance in designing experiments for validation.

  18. 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.

  19. Modeling of column apparatus processes

    CERN Document Server

    Boyadjiev, Christo; Boyadjiev, Boyan; Popova-Krumova, Petya

    2016-01-01

    This book presents a new approach for the modeling of chemical and interphase mass transfer processes in industrial column apparatuses, using convection-diffusion and average-concentration models. The convection-diffusion type models are used for a qualitative analysis of the processes and to assess the main, small and slight physical effects, and then reject the slight effects. As a result, the process mechanism can be identified. It also introduces average concentration models for quantitative analysis, which use the average values of the velocity and concentration over the cross-sectional area of the column. The new models are used to analyze different processes (simple and complex chemical reactions, absorption, adsorption and catalytic reactions), and make it possible to model the processes of gas purification with sulfur dioxide, which form the basis of several patents.

  20. Technical-and-Economic Efficiency of Draft Enriched with Oxygen in Small-Capacity Heating Boilers

    Directory of Open Access Journals (Sweden)

    P. Ratnikov

    2013-01-01

    Full Text Available Data on complex experimental and theoretical investigations pertaining to efficiency of oxygen-enriched draft in the small-capacity heating boilers as exemplified by the plant HEIZA (HW-S-10/K have been presented in the paper. The paper provides a calculation model of heating processes in heat generator burner (as exemplified by HEIZA plant. Simulation of heating processes in the operational zone has been executed in paper. The experimental data have proved model adequacy. The calculation scheme of the plant will be used in future for determination of power and ecological efficiency of draft enrichment with oxygen.

  1. RELIABILITY ANALYSIS OF A SYSTEM OF BOILER USED IN READYMADE GARMENT INDUSTRY

    Directory of Open Access Journals (Sweden)

    R.K. Agnihotri

    2008-01-01

    Full Text Available The present paper deals with the reliability analysis of a system of boiler used in garment industry.The system consists of a single unit of boiler which plays an important role in garment industry. Usingregenerative point technique with Markov renewal process various reliability characteristics of interest areobtained.

  2. UML in business process modeling

    Directory of Open Access Journals (Sweden)

    Bartosz Marcinkowski

    2013-03-01

    Full Text Available Selection and proper application of business process modeling methods and techniques have a significant impact on organizational improvement capabilities as well as proper understanding of functionality of information systems that shall support activity of the organization. A number of business process modeling notations were popularized in practice in recent decades. Most significant of the notations include Business Process Modeling Notation (OMG BPMN and several Unified Modeling Language (OMG UML extensions. In this paper, the assessment whether one of the most flexible and strictly standardized contemporary business process modeling notations, i.e. Rational UML Profile for Business Modeling, enable business analysts to prepare business models that are all-embracing and understandable by all the stakeholders. After the introduction, methodology of research is discussed. Section 2 presents selected case study results. The paper is concluded with a summary.

  3. Modeling Software Processes and Artifacts

    NARCIS (Netherlands)

    van den Berg, Klaas; Bosch, Jan; Mitchell, Stuart

    1997-01-01

    The workshop on Modeling Software Processes and Artifacts explored the application of object technology in process modeling. After the introduction and the invited lecture, a number of participants presented their position papers. First, an overview is given on some background work, and the aims, as

  4. Boiler using combustible fluid

    Science.gov (United States)

    Baumgartner, H.; Meier, J.G.

    1974-07-03

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

  5. Multi-enzyme Process Modeling

    DEFF Research Database (Denmark)

    Andrade Santacoloma, Paloma de Gracia

    . In this way the model parameters that drives the main dynamic behavior can be identified and thus a better understanding of this type of processes. In order to develop, test and verify the methodology, three case studies were selected, specifically the bi-enzyme process for the production of lactobionic acid......The subject of this thesis is to develop a methodological framework that can systematically guide mathematical model building for better understanding of multi-enzyme processes. In this way, opportunities for process improvements can be identified by analyzing simulations of either existing...... in the scientific literature. Reliable mathematical models of such multi-catalytic schemes can exploit the potential benefit of these processes. In this way, the best outcome of the process can be obtained understanding the types of modification that are required for process optimization. An effective evaluation...

  6. Business process modeling in healthcare.

    Science.gov (United States)

    Ruiz, Francisco; Garcia, Felix; Calahorra, Luis; Llorente, César; Gonçalves, Luis; Daniel, Christel; Blobel, Bernd

    2012-01-01

    The importance of the process point of view is not restricted to a specific enterprise sector. In the field of health, as a result of the nature of the service offered, health institutions' processes are also the basis for decision making which is focused on achieving their objective of providing quality medical assistance. In this chapter the application of business process modelling - using the Business Process Modelling Notation (BPMN) standard is described. Main challenges of business process modelling in healthcare are the definition of healthcare processes, the multi-disciplinary nature of healthcare, the flexibility and variability of the activities involved in health care processes, the need of interoperability between multiple information systems, and the continuous updating of scientific knowledge in healthcare.

  7. Nongray-gas Effects in Modeling of Large-scale Oxy-fuel Combustion Processes

    DEFF Research Database (Denmark)

    Yin, Chungen

    2012-01-01

    , among which radiative heat transfer under oxy-fuel conditions is one of the fundamental issues. This paper demonstrates the nongray-gas effects in modeling of large-scale oxy-fuel combustion processes. Oxy-fuel combustion of natural gas in a large-scale utility boiler is numerically investigated...... cases. The simulation results show that the gray and non-gray calculations of the same oxy-fuel WSGGM make distinctly different predictions in the wall radiative heat transfer, incident radiative flux, radiative source, gas temperature and species profiles. In relative to the non-gray implementation...

  8. Modeling nuclear processes by Simulink

    Energy Technology Data Exchange (ETDEWEB)

    Rashid, Nahrul Khair Alang Md, E-mail: nahrul@iium.edu.my [Faculty of Engineering, International Islamic University Malaysia, Jalan Gombak, Selangor (Malaysia)

    2015-04-29

    Modelling and simulation are essential parts in the study of dynamic systems behaviours. In nuclear engineering, modelling and simulation are important to assess the expected results of an experiment before the actual experiment is conducted or in the design of nuclear facilities. In education, modelling can give insight into the dynamic of systems and processes. Most nuclear processes can be described by ordinary or partial differential equations. Efforts expended to solve the equations using analytical or numerical solutions consume time and distract attention from the objectives of modelling itself. This paper presents the use of Simulink, a MATLAB toolbox software that is widely used in control engineering, as a modelling platform for the study of nuclear processes including nuclear reactor behaviours. Starting from the describing equations, Simulink models for heat transfer, radionuclide decay process, delayed neutrons effect, reactor point kinetic equations with delayed neutron groups, and the effect of temperature feedback are used as examples.

  9. Modeling nuclear processes by Simulink

    Science.gov (United States)

    Rashid, Nahrul Khair Alang Md

    2015-04-01

    Modelling and simulation are essential parts in the study of dynamic systems behaviours. In nuclear engineering, modelling and simulation are important to assess the expected results of an experiment before the actual experiment is conducted or in the design of nuclear facilities. In education, modelling can give insight into the dynamic of systems and processes. Most nuclear processes can be described by ordinary or partial differential equations. Efforts expended to solve the equations using analytical or numerical solutions consume time and distract attention from the objectives of modelling itself. This paper presents the use of Simulink, a MATLAB toolbox software that is widely used in control engineering, as a modelling platform for the study of nuclear processes including nuclear reactor behaviours. Starting from the describing equations, Simulink models for heat transfer, radionuclide decay process, delayed neutrons effect, reactor point kinetic equations with delayed neutron groups, and the effect of temperature feedback are used as examples.

  10. An optimization model for the operations of steam production in industrial boilers Um modelo de otimização para as operações de produção de vapor em caldeiras industriais

    Directory of Open Access Journals (Sweden)

    Cleber Damião Rocco

    2012-01-01

    Full Text Available In this study, a mixed integer linear programming model is presented to support some of the key decisions in the steam production system with industrial boilers. The model approaches the fuel management decisions (fuel replenishment and its inventory control, boiler operational decisions (start-up, warm-up, and shutdown operations, and which boiler should produce steam. The model adjustments and its validation were carried out through a case study in a large food industry. In face of the good outcomes achieved in applying the model and the lack of optimization tools to support the decisions in this system, the proposed model is a suitable alternative to support some of the key decisions in the system of steam production with multiple industrial boilers.Apresenta-se neste trabalho um modelo de programação linear inteira mista para apoiar algumas das principais decisões na operação de produção de vapor em caldeiras industriais. O modelo contempla as decisões de gerenciamento dos combustíveis: compra nos fornecedores, transporte para a fábrica e níveis dos estoques, assim como determina o modo de funcionamento das caldeiras: momentos de acionamento (start-up, regime de aquecimento (warm-up e desligamento dos equipamentos (shutdown, e em quais deles haverá produção de vapor. Os ajustes e a validação do modelo ocorreram por meio de um estudo de caso realizado em uma indústria de alimentos de grande porte. Diante dos bons resultados obtidos com a aplicação do modelo e da ausência de protocolos ou ferramentas de otimização para apoiar as decisões no sistema estudado, o modelo proposto apresenta-se como uma alternativa viável para apoiar algumas das principais decisões no sistema de produção de vapor em caldeiras industriais.

  11. Boiler for generating high quality vapor

    Science.gov (United States)

    Gray, V. H.; Marto, P. J.; Joslyn, A. W.

    1972-01-01

    Boiler supplies vapor for use in turbines by imparting a high angular velocity to the liquid annulus in heated rotating drum. Drum boiler provides a sharp interface between boiling liquid and vapor, thereby, inhibiting the formation of unwanted liquid droplets.

  12. Sato Processes in Default Modeling

    DEFF Research Database (Denmark)

    Kokholm, Thomas; Nicolato, Elisa

    In reduced form default models, the instantaneous default intensity is classically the modeling object. Survival probabilities are then given by the Laplace transform of the cumulative hazard defined as the integrated intensity process. Instead, recent literature has shown a tendency towards...... specifying the cumulative hazard process directly. Within this framework we present a new model class where cumulative hazards are described by self-similar additive processes, also known as Sato processes. Furthermore we also analyze specifications obtained via a simple deterministic time......-change of a homogeneous Levy process. While the processes in these two classes share the same average behavior over time, the associated intensities exhibit very different properties. Concrete specifications are calibrated to data on the single names included in the iTraxx Europe index. The performances are compared...

  13. Sato Processes in Default Modeling

    DEFF Research Database (Denmark)

    Kokholm, Thomas; Nicolato, Elisa

    2010-01-01

    In reduced form default models, the instantaneous default intensity is the classical modeling object. Survival probabilities are then given by the Laplace transform of the cumulative hazard defined as the integrated intensity process. Instead, recent literature tends to specify the cumulative...... hazard process directly. Within this framework we present a new model class where cumulative hazards are described by self-similar additive processes, also known as Sato processes. Furthermore, we analyze specifications obtained via a simple deterministic time-change of a homogeneous Lévy process. While...... the processes in these two classes share the same average behavior over time, the associated intensities exhibit very different properties. Concrete specifications are calibrated to data on all the single names included in the iTraxx Europe index. The performances are compared with those of the classical CIR...

  14. ECUT energy data reference series: boilers

    Energy Technology Data Exchange (ETDEWEB)

    Chockie, A.D.; Johnson, D.R.

    1984-09-01

    Information on the population and fuel consumption of water-tube, fire-tube and cast iron boilers is summarized. The use of each boiler type in the industrial and commercial sector is examined. Specific information on each boiler type includes (for both 1980 and 2000) the average efficiency of the boiler, the capital stock, the amount of fuel consumed, and the activity level as measured by operational load factor.

  15. Modelling of CWS combustion process

    Science.gov (United States)

    Rybenko, I. A.; Ermakova, L. A.

    2016-10-01

    The paper considers the combustion process of coal water slurry (CWS) drops. The physico-chemical process scheme consisting of several independent parallel-sequential stages is offered. This scheme of drops combustion process is proved by the particle size distribution test and research stereomicroscopic analysis of combustion products. The results of mathematical modelling and optimization of stationary regimes of CWS combustion are provided. During modeling the problem of defining possible equilibrium composition of products, which can be obtained as a result of CWS combustion processes at different temperatures, is solved.

  16. On-Line Life Monitoring Technique for Tube Bundles of Boiler High-Temperature Heating Surface

    Institute of Scientific and Technical Information of China (English)

    Yang Dong; Wang Zhongyuan

    2005-01-01

    High-temperature heating surface such as superheater and reheater of large-sized utility boiler all experiences a relatively severe working conditions. The failure of boiler tubes will directly impact the safe and economic operation of boiler. An on-line life monitoring model of high-temperature heating surface was set up according to the well-known L-M formula of the creep damages. The tube wall metal temperature and working stress was measured by on-line monitoring, and with this model, the real-time calculation of the life expenditure of the heating surface tube bundles were realized. Based on the technique the on-line life monitoring and management system of high-temperature heating surface was developed for a 300 MW utility boiler. An effective device was thus suggested for the implementation of the safe operation and the condition-based maintenance of utility boilers.

  17. Social Models: Blueprints or Processes?

    Science.gov (United States)

    Little, Graham R.

    1981-01-01

    Discusses the nature and implications of two different models for societal planning: (1) the problem-solving process approach based on Karl Popper; and (2) the goal-setting "blueprint" approach based on Karl Marx. (DC)

  18. Characteristics and sources of intermediate size particles in recovery boilers : final project report.

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, Larry L. (Brigham Young University, Provo, UT); Shaddix, Christopher R.; Verrill, Christopher L. (Georgia Institute of Technology, Institute of Paper Science and Technology, Atlanta, GA); Wessel, Richard A. (Babcock & Wilcox Company, Barberton, OH)

    2005-02-01

    As part of the U.S. Department of Energy (DOE) Office of Industrial Technologies (OIT) Industries of the Future (IOF) Forest Products research program, a collaborative investigation was conducted on the sources, characteristics, and deposition of particles intermediate in size between submicron fume and carryover in recovery boilers. Laboratory experiments on suspended-drop combustion of black liquor and on black liquor char bed combustion demonstrated that both processes generate intermediate size particles (ISP), amounting to 0.5-2% of the black liquor dry solids mass (BLS). Measurements in two U.S. recovery boilers show variable loadings of ISP in the upper furnace, typically between 0.6-3 g/Nm{sup 3}, or 0.3-1.5% of BLS. The measurements show that the ISP mass size distribution increases with size from 5-100 {micro}m, implying that a substantial amount of ISP inertially deposits on steam tubes. ISP particles are depleted in potassium, chlorine, and sulfur relative to the fuel composition. Comprehensive boiler modeling demonstrates that ISP concentrations are substantially overpredicted when using a previously developed algorithm for ISP generation. Equilibrium calculations suggest that alkali carbonate decomposition occurs at intermediate heights in the furnace and may lead to partial destruction of ISP particles formed lower in the furnace. ISP deposition is predicted to occur in the superheater sections, at temperatures greater than 750 C, when the particles are at least partially molten.

  19. Characteristics and sources of intermediate size particles in recovery boilers : final project report.

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, Larry L. (Brigham Young University, Provo, UT); Shaddix, Christopher R.; Verrill, Christopher L. (Georgia Institute of Technology, Institute of Paper Science and Technology, Atlanta, GA); Wessel, Richard A. (Babcock & Wilcox Company, Barberton, OH)

    2005-02-01

    As part of the U.S. Department of Energy (DOE) Office of Industrial Technologies (OIT) Industries of the Future (IOF) Forest Products research program, a collaborative investigation was conducted on the sources, characteristics, and deposition of particles intermediate in size between submicron fume and carryover in recovery boilers. Laboratory experiments on suspended-drop combustion of black liquor and on black liquor char bed combustion demonstrated that both processes generate intermediate size particles (ISP), amounting to 0.5-2% of the black liquor dry solids mass (BLS). Measurements in two U.S. recovery boilers show variable loadings of ISP in the upper furnace, typically between 0.6-3 g/Nm{sup 3}, or 0.3-1.5% of BLS. The measurements show that the ISP mass size distribution increases with size from 5-100 {micro}m, implying that a substantial amount of ISP inertially deposits on steam tubes. ISP particles are depleted in potassium, chlorine, and sulfur relative to the fuel composition. Comprehensive boiler modeling demonstrates that ISP concentrations are substantially overpredicted when using a previously developed algorithm for ISP generation. Equilibrium calculations suggest that alkali carbonate decomposition occurs at intermediate heights in the furnace and may lead to partial destruction of ISP particles formed lower in the furnace. ISP deposition is predicted to occur in the superheater sections, at temperatures greater than 750 C, when the particles are at least partially molten.

  20. 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.

  1. 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.

  2. Application of digital holography to circle flow bed boiler measurement

    Institute of Scientific and Technical Information of China (English)

    PU Shiliang; Denis Lebrun; WANG Qinghui; CEN Kefa; REN Kuanfang

    2007-01-01

    The spatial distribution of particles in the boiler is very important in the study on the circle flow bed boiler (CFB). Digital in-line holography technique was applied to obtain the spatial and diameter distribution of the particles inside the boiler. A HE-NE laser was used to illuminate the particles inside the CFB through two glass windows and the in-line diffraction pattern was recorded by a CCD camera. The diffraction can be interpreted as a convolution between a family of wavelet functions and the object function. So the three-dimensional (3D) images of the particles in the two-phase flow were reconstructed by the convolution between diffraction pattern and wavelet functions. The particle diameters and 3D coordinates were calculated from the reconstructed 3D images by a series of image-processing methods, followed by a discussion of the experimental results.

  3. Model feedstock supply processing plants

    Directory of Open Access Journals (Sweden)

    V. M. Bautin

    2013-01-01

    Full Text Available The model of raw providing the processing enterprises entering into vertically integrated structure on production and processing of dairy raw materials, differing by an orientation on achievement of cumulative effect by the integrated structure acting as criterion function which maximizing is reached by optimization of capacities, volumes of deliveries of raw materials and its qualitative characteristics, costs of industrial processing of raw materials and demand for dairy production is developed.

  4. CFD Studies on Multi Lead Rifled [MLR] Boiler Tubes

    Directory of Open Access Journals (Sweden)

    Dr T C Mohankumar

    2013-09-01

    Full Text Available This paper reports the merits of multi lead rifled [MLR] tubes in vertical water tube boiler using CFD tool. Heat transfer enhancement of MLR tubes was mainly taken in to consideration. Performance of multi lead rifled tube was studied by varying its influencing geometrical parameter like number of rifling, height of rifling, length of pitch of rifling for a particular length. The heat transfer analysis was done at operating conditions of an actual coal fired water tube boiler situated at Apollo Tyres LTD, Chalakudy, India for saturated process steam production. The results showed that the heat transfer increased when compared with existing inner plane wall water tubes.

  5. Multiloop control of a drum boiler

    Directory of Open Access Journals (Sweden)

    Alena Kozáková

    2014-05-01

    Full Text Available The Equivalent Subsystems Method (ESM (Kozáková et al., 2011 is methodology of decentralized controller design in the frequency domain which allows designing local controllers using any SISO frequency domain method. The paper deals with the digital ESM version where digital local PID controllers guaranteeing required performance for the full system are designed for individual equivalent subsystems using the practice-oriented Sine-wave method (Bucz et al., 2012. The proposed decentralized controller design procedure was verified on the nonlinear benchmark drum boiler simulation model (Morilla, 2012.

  6. Model Checking of Boolean Process Models

    CERN Document Server

    Schneider, Christoph

    2011-01-01

    In the field of Business Process Management formal models for the control flow of business processes have been designed since more than 15 years. Which methods are best suited to verify the bulk of these models? The first step is to select a formal language which fixes the semantics of the models. We adopt the language of Boolean systems as reference language for Boolean process models. Boolean systems form a simple subclass of coloured Petri nets. Their characteristics are low tokens to model explicitly states with a subsequent skipping of activations and arbitrary logical rules of type AND, XOR, OR etc. to model the split and join of the control flow. We apply model checking as a verification method for the safeness and liveness of Boolean systems. Model checking of Boolean systems uses the elementary theory of propositional logic, no modal operators are needed. Our verification builds on a finite complete prefix of a certain T-system attached to the Boolean system. It splits the processes of the Boolean sy...

  7. Load control and the provision of the efficiency of steam boilers equipped with an extremal governor

    Science.gov (United States)

    Sabanin, V. P.; Kormilitsyn, V. I.; Kostyk, V. I.; Smirnov, N. I.; Koroteev, A. V.; Repin, A. I.

    2014-12-01

    This paper presents an analysis of main problems of controlling small- and medium-size steam boilers. Noted are deficiencies of current normative and technical documents, as well as those of the traditional concept of the process of fuel firing, the methods for and algorithms of boiler control. There is established an approach to creation of such control systems in which a boiler is treated, as to control and load channels, as a nonlinear linked controlled objects. To control load and efficiency of a boiler, an universal schematic diagram is suggested that allows for the possibility of implementation in modern controllers of both known methods and a new method using an extremal governor, which would provide minimum fuel consumption at given thermal load of a boiler.

  8. Final technical report. In-situ FT-IR monitoring of a black liquor recovery boiler

    Energy Technology Data Exchange (ETDEWEB)

    James Markham; Joseph Cosgrove; David Marran; Jorge Neira; Chad Nelson; Peter Solomon

    1999-05-31

    This project developed and tested advanced Fourier transform infrared (FT-IR) instruments for process monitoring of black liquor recovery boilers. The state-of-the-art FT-IR instruments successfully operated in the harsh environment of a black liquor recovery boiler and provided a wealth of real-time process information. Concentrations of multiple gas species were simultaneously monitored in-situ across the combustion flow of the boiler and extractively at the stack. Sensitivity to changes of particulate fume and carryover levels in the process flow were also demonstrated. Boiler set-up and operation is a complex balance of conditions that influence the chemical and physical processes in the combustion flow. Operating parameters include black liquor flow rate, liquor temperature, nozzle pressure, primary air, secondary air, tertiary air, boiler excess oxygen and others. The in-process information provided by the FT-IR monitors can be used as a boiler control tool since species indicative of combustion efficiency (carbon monoxide, methane) and pollutant emissions (sulfur dioxide, hydrochloric acid and fume) were monitored in real-time and observed to fluctuate as operating conditions were varied. A high priority need of the U.S. industrial boiler market is improved measurement and control technology. The sensor technology demonstrated in this project is applicable to the need of industry.

  9. Computer Modelling of Dynamic Processes

    Directory of Open Access Journals (Sweden)

    B. Rybakin

    2000-10-01

    Full Text Available Results of numerical modeling of dynamic problems are summed in the article up. These problems are characteristic for various areas of human activity, in particular for problem solving in ecology. The following problems are considered in the present work: computer modeling of dynamic effects on elastic-plastic bodies, calculation and determination of performances of gas streams in gas cleaning equipment, modeling of biogas formation processes.

  10. Command Process Modeling & Risk Analysis

    Science.gov (United States)

    Meshkat, Leila

    2011-01-01

    Commanding Errors may be caused by a variety of root causes. It's important to understand the relative significance of each of these causes for making institutional investment decisions. One of these causes is the lack of standardized processes and procedures for command and control. We mitigate this problem by building periodic tables and models corresponding to key functions within it. These models include simulation analysis and probabilistic risk assessment models.

  11. Path modeling and process control

    DEFF Research Database (Denmark)

    Høskuldsson, Agnar; Rodionova, O.; Pomerantsev, A.

    2007-01-01

    and having three or more stages. The methods are applied to a process control of a multi-stage production process having 25 variables and one output variable. When moving along the process, variables change their roles. It is shown how the methods of path modeling can be applied to estimate variables...... of the next stage with the purpose of obtaining optimal or almost optimal quality of the output variable. An important aspect of the methods presented is the possibility of extensive graphic analysis of data that can provide the engineer with a detailed view of the multi-variate variation in data.......Many production processes are carried out in stages. At the end of each stage, the production engineer can analyze the intermediate results and correct process parameters (variables) of the next stage. Both analysis of the process and correction to process parameters at next stage should...

  12. Modelling Hospital Materials Management Processes

    Directory of Open Access Journals (Sweden)

    Raffaele Iannone

    2013-06-01

    integrated and detailed analysis and description model for hospital materials management data and tasks, which is able to tackle information from patient requirements to usage, from replenishment requests to supplying and handling activities. The model takes account of medical risk reduction, traceability and streamlined processes perspectives. Second, the paper translates this information into a business process model and mathematical formalization.The study provides a useful guide to the various relevant technology‐related, management and business issues, laying the foundations of an efficient reengineering of the supply chain to reduce healthcare costs and improve the quality of care.

  13. 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...

  14. 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

  15. 自然循环汽包炉蒸发回路稳态数学模型%A Steady-state Model of Drum-downcomer-riser Loop in Natural Circulation Drum-type Boilers

    Institute of Scientific and Technical Information of China (English)

    刘福国; 何传怀

    2014-01-01

    A steady-state model was developed which gave detailed account of the thermal-hydraulic phenomena in down-comer-riser-drum loop of a natural circulation drum-type boiler. The model was composed of mass, energy and momentum conservation equations, together with algebraic relationships to describe the working fluids properties and phase change. The empirical relative distribution of heat flux along the height of the furnace was used to drive the model, the averaged heat flux in furnace was solved as unknown, and this fairly accords with the physical process. The model is capable of predicting working fluids temperature, pressure, circulation flow-rates and steam distributions in risers under various operating conditions. Results of the simulation provide a clear insight into two-phase flow and heat transfer conditions in evaporating tubes, and predicated circulation ratios are consistent with results obtained in other literatures.%建立了自然循环汽包炉下降管-上升管-汽包回路的稳态数学模型,该模型是由物质、能量和动量微分方程以及工质物性和相变代数方程组成,炉膛相对热负荷沿高度的一维经验分布作为模型的驱动方程,炉膛平均热负荷是求解变量,因此,热负荷不是独立变量,它与汽包产生的蒸汽量相关,这与实际物理过程较好地相符。该模型能够预测不同运行状态下工质在上升管内的压力、温度、循环流量以及含汽率分布,模拟结果给出了蒸发管内两相流动和传热的清晰图景,循环倍率的预测值与有关文献给出的结果相一致。

  16. Modeling total reduced sulfur and sulfur dioxide emissions from a kraft recovery boiler using an artificial neural network, and, Investigating volatile organic compounds in an urban intermountain valley using a TD/GC/MS methodology and intrinsic tracer molecules

    Science.gov (United States)

    Wrobel, Christopher Louis

    2000-11-01

    Back-propagation neural networks were trained to predict total reduced sulfur (TRS) and SO2 emissions from kraft recovery boiler operational data. A 0.721 coefficient of correlation was achieved between actual and predicted sulfur emissions on test data withheld from network training. The artificial neural network (ANN) models found an inverse, linear relationship between TRS/SO2 emissions and percent opacity. A number of relationships among operating parameters and sulfur emissions were identified by the ANN models. These relationships were used to formulate strategies for reducing sulfur emissions. Disagreement between ANN model predictions on a subsequent data set revealed an additional scenario for sulfur release not present in the training data. ANN modeling was demonstrated to be an effective tool for analyzing process variables when balancing productivity and environmental concerns. Five receptor sites distributed in the Missoula Valley, Montana, were employed to investigate possible VOC (benzene, 2,3,4-trimethylpentane, toluene, ethylbenzene, m-/p-xylene, o-xylene, naphthalene, acetone, chloroform, α-pinene, β-pinene, p-cymene and limonene) sources. The most dominant source of VOCs was found to be vehicle emissions. Furthermore, anthropogenic sources of terpenoids overwhelmed biogenic emissions, on a local scale. Difficulties correlating wind direction and pollutant levels could be explained by wind direction variability, low wind speed and seasonally dependent meteorological factors. Significant evidence was compiled to support the use of p-cymene as a tracer molecule for pulp mill VOC emissions. Apportionment techniques using o-xylene and p-cymene as tracers for automobile and pulp mill emissions, respectively, were employed to estimate each source's VOC contribution. Motor vehicles were estimated to contribute between 56 and 100 percent of the aromatic pollutants in the Missoula Valley airshed, depending upon the sampling location. Pulp mill emissions

  17. INCREASING OF EFFICIENCY OF NATURAL GAS COMBUSTION IN STEAM BOILERS OF SMALL AND MEDIUM CAPACITY DUE TO IMPROVED MIXTURE FORMATION

    Directory of Open Access Journals (Sweden)

    Gaponenko A. M.

    2014-12-01

    Full Text Available The article presents methods of industrial tests of the of technical device utility model designed for boilers E-1,0-0,9G-3 QL-500, D-721 of small and medium capacity. The research is aimed at improving the efficiency of fuel combustion in the boiler furnaces due to uniform distribution of airflow when supplying it to the boiler burner

  18. ECONOMIC MODELING PROCESSES USING MATLAB

    Directory of Open Access Journals (Sweden)

    Anamaria G. MACOVEI

    2008-06-01

    Full Text Available To study economic phenomena and processes using mathem atical modeling, and to determine the approximatesolution to a problem we need to choose a method of calculation and a numerical computer program, namely thepackage of programs MatLab. Any economic process or phenomenon is a mathematical description of h is behavior,and thus draw up an economic and mathematical model that has the following stages: formulation of the problem, theanalysis process modeling, the production model and design verification, validation and implementation of the model.This article is presented an economic model and its modeling is using mathematical equations and software packageMatLab, which helps us approximation effective solution. As data entry is considered the net cost, the cost of direct andtotal cost and the link between them. I presented the basic formula for determining the total cost. Economic modelcalculations were made in MatLab software package and with graphic representation of its interpretation of the resultsachieved in terms of our specific problem.

  19. Active brickworks - phase I[For application in biofuel boilers]; Aktiva murverk - etapp I

    Energy Technology Data Exchange (ETDEWEB)

    Wrangensten, Lars; Schuster, Robert; Ingman, Rolf; Sendelius, Mikael; Ehleskog, Rickard [AaF-Energikonsult AB, Stockholm (Sweden)

    2003-10-01

    This report is the first step of the R and D project 'Active brickworks' within the program 'Possibilities to improve the operation conditions in industrial bark boilers by optimised combustion control'. Good high temperature resistance is one of the major characteristics of ceramics. They are based on quartz and aluminium oxide, an attachment component (acid or cement) and also different types of additives which, together with the heating treatment, gives the ceramic materials their features. The brickwork in a boiler has several assignments. First of all resistance to corrosion, erosion and protection against fouling of the water tube walls, but also to significant affect the combustion process by energy saving features and heating radiation. This project has been focused on the last named features, namely to be able to make a more active choice of brickwork in order to utilise the ceramic features and hereby making it possible to lower the combustion process emissions. The material samples received from the manufactures have been tested in a small-scale laboratory rig. Features investigated are emissivity/reflection, heat conductivity and heat capacity. Mathematic simulations have also been performed with a representative type boiler model in order to make conclusions concerning how the results can be transformed to and applied in a real full-scale boiler. The most important designing case for ceramics in bark boilers is when boiler load rapidly increases or during a fast fuel moisture change from dry to wet fuel. It has been concluded in the study that that the ceramic walls in a boiler should be divided into different layers. The outer layer in the ceiling and sidewalls of the drying zone must consist of highly insulating material in order to get a high temperature of heating surfaces close to the furnace. To store heat during load transients the heating surfaces must have high emissivity factor and good heating capacity. From this point of

  20. Numerical investigation of ash deposition in straw-fired boilers

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen

    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...

  1. Modeling of the Hydroentanglement Process

    Directory of Open Access Journals (Sweden)

    Ping Xiang

    2006-11-01

    Full Text Available Mechanical performance of hydroentangled nonwovens is determined by the degree of the fiber entanglement, which depends on parameters of the fibers, fiberweb, forming surface, water jet and the process speed. This paper develops a computational fluid dynamics model of the hydroentanglement process. Extensive comparison with experimental data showed that the degree of fiber entanglement is linearly related to flow vorticity in the fiberweb, which is induced by impinging water jets. The fiberweb is modeled as a porous material of uniform porosity and the actual geometry of forming wires is accounted for in the model. Simulation results are compared with experimental data for a Perfojet ® sleeve and four woven forming surfaces. Additionally, the model is used to predict the effect of fiberweb thickness on the degree of fiber entanglement for different forming surfaces.

  2. Multivariable robust adaptive sliding mode control of an industrial boiler-turbine in the presence of modeling imprecisions and external disturbances: A comparison with type-I servo controller.

    Science.gov (United States)

    Ghabraei, Soheil; Moradi, Hamed; Vossoughi, Gholamreza

    2015-09-01

    To guarantee the safety and efficient performance of the power plant, a robust controller for the boiler-turbine unit is needed. In this paper, a robust adaptive sliding mode controller (RASMC) is proposed to control a nonlinear multi-input multi-output (MIMO) model of industrial boiler-turbine unit, in the presence of unknown bounded uncertainties and external disturbances. To overcome the coupled nonlinearities and investigate the zero dynamics, input-output linearization is performed, and then the new decoupled inputs are derived. To tackle the uncertainties and external disturbances, appropriate adaption laws are introduced. For constructing the RASMC, suitable sliding surface is considered. To guarantee the sliding motion occurrence, appropriate control laws are constructed. Then the robustness and stability of the proposed RASMC is proved via Lyapunov stability theory. To compare the performance of the purposed RASMC with traditional control schemes, a type-I servo controller is designed. To evaluate the performance of the proposed control schemes, simulation studies on nonlinear MIMO dynamic system in the presence of high frequency bounded uncertainties and external disturbances are conducted and compared. Comparison of the results reveals the superiority of proposed RASMC over the traditional control schemes. RAMSC acts efficiently in disturbance rejection and keeping the system behavior in desirable tracking objectives, without the existence of unstable quasi-periodic solutions.

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

    Directory of Open Access Journals (Sweden)

    Tingfang Yu

    2013-06-01

    Full Text Available 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 predicted by the BP neural network model showed good agreement with the measured. Then, BP model and the non-dominated sorting genetic algorithm II (NSGA-II were combined to gain the optimal operating parameters which lead to lower NOx emissions and overall heat loss boiler. The optimization results showed that hybrid algorithm by combining BP neural network with NSGA-II can be a good tool to solve the problem of multi-objective optimization of a coal-fired combustion, which can reduce NOx emissions and overall heat loss effectively for the coal-fired boiler.

  4. Modified Claus process probabilistic model

    Energy Technology Data Exchange (ETDEWEB)

    Larraz Mora, R. [Chemical Engineering Dept., Univ. of La Laguna (Spain)

    2006-03-15

    A model is proposed for the simulation of an industrial Claus unit with a straight-through configuration and two catalytic reactors. Process plant design evaluations based on deterministic calculations does not take into account the uncertainties that are associated with the different input variables. A probabilistic simulation method was applied in the Claus model to obtain an impression of how some of these inaccuracies influences plant performance. (orig.)

  5. Process Models for Security Architectures

    Directory of Open Access Journals (Sweden)

    Floarea NASTASE

    2006-01-01

    Full Text Available This paper presents a model for an integrated security system, which can be implemented in any organization. It is based on security-specific standards and taxonomies as ISO 7498-2 and Common Criteria. The functionalities are derived from the classes proposed in the Common Criteria document. In the paper we present the process model for each functionality and also we focus on the specific components.

  6. Multi-enzyme Process Modeling

    DEFF Research Database (Denmark)

    Andrade Santacoloma, Paloma de Gracia

    The subject of this thesis is to develop a methodological framework that can systematically guide mathematical model building for better understanding of multi-enzyme processes. In this way, opportunities for process improvements can be identified by analyzing simulations of either existing...... are affected (in a positive or negative way) by the presence of the other enzymes and compounds in the media. In this thesis the concept of multi-enzyme in-pot term is adopted for processes that are carried out by the combination of enzymes in a single reactor and implemented at pilot or industrial scale...

  7. 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.

  8. 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...

  9. Modeling of biopharmaceutical processes. Part 2: Process chromatography unit operation

    DEFF Research Database (Denmark)

    Kaltenbrunner, Oliver; McCue, Justin; Engel, Philip;

    2008-01-01

    Process modeling can be a useful tool to aid in process development, process optimization, and process scale-up. When modeling a chromatography process, one must first select the appropriate models that describe the mass transfer and adsorption that occurs within the porous adsorbent...

  10. Network Model Building (Process Mapping)

    OpenAIRE

    Blau, Gary; Yih, Yuehwern

    2004-01-01

    12 slides Provider Notes:See Project Planning Video (Windows Media) Posted at the bottom are Gary Blau's slides. Before watching, please note that "process mapping" and "modeling" are mentioned in the video and notes. Here they are meant to refer to the NSCORT "project plan"

  11. A unified linear-time temporal logic solution to the steam-boiler control specification problem

    Institute of Scientific and Technical Information of China (English)

    闫安; 唐稚松

    1999-01-01

    The TLL XYZ/E is a formal language able to represent the dynamic semantics and the static semantics in a unified framework. It supports the whole process of program development, i.e. from the abstract specification to the efficiently executable program in a formal, precise and convenient way. The steam boiler control specification problem, a large case study in the fields of real time, hybrid and communication systems, is discussed with XYZ/E. The approach covers physical model construction, formal specification, stepwise refinement, verification, executable program and visual user interface programming.

  12. CHP as a Boiler Replacement Opportunity (Webinar) – April 30, 2013

    Science.gov (United States)

    This webinar provides information about the benefits of replacing a boiler with a CHP system, describes CHP project analysis and delivery processes, and highlights a case study at Penn State University.

  13. Modeling of the reburning process

    Energy Technology Data Exchange (ETDEWEB)

    Rota, R.; Bonini, F.; Servida, A.; Morbidelli, M.; Carra, S. [Politecnico di Milano, Milano (Italy). Dip. di Chimica Fisica Applicata

    1997-07-01

    Reburning has become a popular method of abating NO{sub x} emission in power plants. Its effectiveness is strongly affected by the interaction between gas phase chemistry and combustion chamber fluid dynamics. Both the mixing of the reactant streams and the elementary reactions in the gas phase control the overall kinetics of the process. This work developed a model coupling a detailed kinetic mechanism to a simplified description of the fluid dynamics of the reburning chamber. The model was checked with reference to experimental data from the literature. Detailed kinetic modeling was found to be essential to describe the reburning process, since the fluid dynamics of the reactor have a strong influence on reactions within. 20 refs., 9 figs., 3 tabs.

  14. The investigation of the impact of basic operational parameters on the dynamics of water jacket in a biomass boiler using numerical and experimental methods

    Directory of Open Access Journals (Sweden)

    Szubel Mateusz

    2015-01-01

    Full Text Available Biomass boiler application, despite its many advantages, is dependent upon many technical aspects, which require tests and optimization. Because of practical constraints, one of the most problematic areas of research is the analysis of phenomena occurring inside the water jacket of the boiler during the combustion process. The issue referred to above is significant due to its direct impact on the heating up of the operating medium for current power of the device and the total efficiency. The paper presents the analytical possibilities of the operating medium in a biomass boiler water jacket. The experimental works conducted as a part of the study were performed using an actual device – EKOPAL RM 40 straw boiler. They were aimed at defining the values of significant boundary conditions. Resistance thermometers and K-type thermocouples connected to a data acquisition system were placed in selected points of the water jacket and the combustion chambers to allow the monitoring of the conditions of the water heating process during biomass combustion. A measurement of inlet water mass flow rate was performed. To develop a numerical model of heat transfer into the water jacket, ANSYS CFX software was applied. The results of the experiments and simulations were compared and discussed. The paper describes the methodology and instruments used to perform the experimental studies, as well as some optimization solutions developed based on the results of the numeric alanalysis.

  15. Non-linear models: coal combustion efficiency and emissions control

    Energy Technology Data Exchange (ETDEWEB)

    Bulsari, A.; Wemberg, A.; Anttila, A.; Multas, A. [Nonlinear Solutions Oy, Turku (Finland)

    2009-04-15

    Today's power plants feel the pressure to limit their NOx emissions and improve their production economics. The article describes how nonlinear models are effective for process guidance of various kinds of processes, including coal fired boilers. These models were developed for the Naantati 2 boiler at the electricity and heat generating coal-fired plant in Naantali, near Turku, Finland. 4 refs., 6 figs.

  16. PIV measurements of the turbulence integral length scale on cold combustion flow field of tangential firing boiler

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Wen-fei; Xie, Jing-xing; Gong, Zhi-jun; Li, Bao-wei [Inner Mongolia Univ. of Science and Technology, Baotou (China). Inner Mongolia Key Lab. for Utilization of Bayan Obo Multi-Metallic Resources: Elected State Key Lab.

    2013-07-01

    The process of the pulverized coal combustion in tangential firing boiler has prominent significance on improving boiler operation efficiency and reducing NO{sub X} emission. This paper aims at researching complex turbulent vortex coherent structure formed by the four corners jets in the burner zone, a cold experimental model of tangential firing boiler has been built. And by employing spatial correlation analysis method and PIV (Particle Image Velocimetry) technique, the law of Vortex scale distribution on the three typical horizontal layers of the model based on the turbulent Integral Length Scale (ILS) has been researched. According to the correlation analysis of ILS and the temporal average velocity, it can be seen that the turbulent vortex scale distribution in the burner zone of the model is affected by both jet velocity and the position of wind layers, and is not linear with the variation of jet velocity. The vortex scale distribution of the upper primary air is significantly different from the others. Therefore, studying the ILS of turbulent vortex integral scale is instructive to high efficiency cleaning combustion of pulverized coal in theory.

  17. 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)

  18. Neural Network Internal Model Control for Superheated Steam Temperature of Supercritical Boiler Unit%超临界锅炉过热汽温神经网络内模控制

    Institute of Scientific and Technical Information of China (English)

    马良玉; 冯谦; 易祖耀

    2013-01-01

    锅炉过热汽温是燃煤机组运行中的重要参数,过高、过低都会对机组的安全经济运行构成威胁.由于锅炉结构复杂,系统庞大,汽温对象具有变时滞、变参数等特性,喷水减温系统采用的串级PID控制,在大范围变工况下效果往往很不理想,且PID参数整定耗时耗力.为此,该文针对600 MW超临界锅炉过热器的喷水减温系统,研究了过热汽温神经网络(ANN)内模控制方案.基于Matlab建立了汽温系统的ANN正模型和逆模型,并设计出ANN内模实时控制器.仿真表明,与原串级PID控制相比,该方案显著改善了过热汽温的控制品质.%Boiler SST was an important parameter closely related to the safe and economic operation of a coal-fired power plant. Superheated steam temperature either too high or too low will pose a threat on the operation safety and economy. Because the boiler superheater system was relatively complex with large delay,large inertia and higher non-linearity, satisfactory control effects can often not be obtained with conventional cascade PID control scheme at wide operating range. Retuning of the PID parameters was often a time-consuming and labor-intensive work. For this reason, a neural network IMC scheme was studied for the two-stage desuperheating system of a 600 MW supercritical boiler unit, studying the system with the method based on superheated steam temperature control scheme. The neural network direct models and inverse models of the superheater system are built and trained with MATLAB software. Then neural network model based IMC controllers for the superheated steam temperature were designed,programmed and tested with a full-scope power plant simulator. It was shown that the neural network IMC scheme can significantly improve the superheated steam temperature control quality compared to the original cascade PID control.

  19. Control Properties of Bottom Fired Marine Boilers

    DEFF Research Database (Denmark)

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

    2005-01-01

    and to verify whether nonlinear control is needed. Finally a controller based on single loop theory is used to analyse if input constraints become active when rejecting transient behaviour from the disturbance steam flow. The model analysis shows large variations in system gains at steady state as function...... supported by a dynamical decoupling. The results indicate that input constraints will become active when the controller responds to transients in the steam flow disturbance. For this reason an MPC (model predictive control) strategy capable of handling constraints on states and control signals should...... the interactions in the system are inspected to analyse potential benefit from using a multivariable control strategy in favour of the current strategy based on single loop theory. An analysis of the nonlinear model is carried out to further determine the nonlinear characteristics of the boiler system...

  20. Animal models and conserved processes

    Directory of Open Access Journals (Sweden)

    Greek Ray

    2012-09-01

    Full Text Available Abstract Background The concept of conserved processes presents unique opportunities for using nonhuman animal models in biomedical research. However, the concept must be examined in the context that humans and nonhuman animals are evolved, complex, adaptive systems. Given that nonhuman animals are examples of living systems that are differently complex from humans, what does the existence of a conserved gene or process imply for inter-species extrapolation? Methods We surveyed the literature including philosophy of science, biological complexity, conserved processes, evolutionary biology, comparative medicine, anti-neoplastic agents, inhalational anesthetics, and drug development journals in order to determine the value of nonhuman animal models when studying conserved processes. Results Evolution through natural selection has employed components and processes both to produce the same outcomes among species but also to generate different functions and traits. Many genes and processes are conserved, but new combinations of these processes or different regulation of the genes involved in these processes have resulted in unique organisms. Further, there is a hierarchy of organization in complex living systems. At some levels, the components are simple systems that can be analyzed by mathematics or the physical sciences, while at other levels the system cannot be fully analyzed by reducing it to a physical system. The study of complex living systems must alternate between focusing on the parts and examining the intact whole organism while taking into account the connections between the two. Systems biology aims for this holism. We examined the actions of inhalational anesthetic agents and anti-neoplastic agents in order to address what the characteristics of complex living systems imply for inter-species extrapolation of traits and responses related to conserved processes. Conclusion We conclude that even the presence of conserved processes is

  1. Energy storage-boiler tank

    Science.gov (United States)

    Chubb, T. A.; Nemecek, J. J.; Simmons, D. E.

    1980-01-01

    Activities performed in an effort to demonstrate heat of fusion energy storage in containerized salts are reported. The properties and cycle life characteristics of a eutectic salt having a boiling point of about 385 C (NaCl, KCl, Mg Cl2) were determined. M-terphenyl was chosen as the heat transfer fluid. Compatibility studies were conducted and mild steel containers were selected. The design and fabrication of a 2MWh storage boiler tank are discussed.

  2. CFD Simulation On CFBC Boiler

    OpenAIRE

    Amol S. Kinkar; G. M. Dhote; R.R. Chokkar

    2015-01-01

    Abstract Heavy industrialization amp modernization of society demands in increasing of power cause to research amp develop new technology amp efficient utilization of existing power units. Variety of sources are available for power generation such as conventional sources like thermal hydro nuclear and renewable sources like wind tidal biomass geothermal amp solar. Out of these most common amp economical way for producing the power is by thermal power stations. Various industrial boilers plays...

  3. Advanced oxidation processes: overall models

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, M. [Univ. de los Andes, Escuela Basica de Ingenieria, La Hechicera, Merida (Venezuela); Curco, D.; Addardak, A.; Gimenez, J.; Esplugas, S. [Dept. de Ingenieria Quimica. Univ. de Barcelona, Barcelona (Spain)

    2003-07-01

    Modelling AOPs implies to consider all the steps included in the process, that means, mass transfer, kinetic (reaction) and luminic steps. In this way, recent works develop models which relate the global reaction rate to catalyst concentration and radiation absorption. However, the application of such models requires to know what is the controlling step for the overall process. In this paper, a simple method is explained which allows to determine the controlling step. Thus, it is assumed that reactor is divided in two hypothetical zones (dark and illuminated), and according to the experimental results, obtained by varying only the reaction volume, it can be decided if reaction occurs only in the illuminated zone or in the all reactor, including dark zone. The photocatalytic degradation of phenol, by using titania degussa P-25 as catalyst, is studied as reaction model. The preliminary results obtained are presented here, showing that it seems that, in this case, reaction only occurs in the illuminated zone of photoreactor. A model is developed to explain this behaviour. (orig.)

  4. Model for amorphous aggregation processes

    Science.gov (United States)

    Stranks, Samuel D.; Ecroyd, Heath; van Sluyter, Steven; Waters, Elizabeth J.; Carver, John A.; von Smekal, Lorenz

    2009-11-01

    The amorphous aggregation of proteins is associated with many phenomena, ranging from the formation of protein wine haze to the development of cataract in the eye lens and the precipitation of recombinant proteins during their expression and purification. While much literature exists describing models for linear protein aggregation, such as amyloid fibril formation, there are few reports of models which address amorphous aggregation. Here, we propose a model to describe the amorphous aggregation of proteins which is also more widely applicable to other situations where a similar process occurs, such as in the formation of colloids and nanoclusters. As first applications of the model, we have tested it against experimental turbidimetry data of three proteins relevant to the wine industry and biochemistry, namely, thaumatin, a thaumatinlike protein, and α -lactalbumin. The model is very robust and describes amorphous experimental data to a high degree of accuracy. Details about the aggregation process, such as shape parameters of the aggregates and rate constants, can also be extracted.

  5. Face Processing: Models For Recognition

    Science.gov (United States)

    Turk, Matthew A.; Pentland, Alexander P.

    1990-03-01

    The human ability to process faces is remarkable. We can identify perhaps thousands of faces learned throughout our lifetime and read facial expression to understand such subtle qualities as emotion. These skills are quite robust, despite sometimes large changes in the visual stimulus due to expression, aging, and distractions such as glasses or changes in hairstyle or facial hair. Computers which model and recognize faces will be useful in a variety of applications, including criminal identification, human-computer interface, and animation. We discuss models for representing faces and their applicability to the task of recognition, and present techniques for identifying faces and detecting eye blinks.

  6. Steady-State Process Modelling

    DEFF Research Database (Denmark)

    2011-01-01

    illustrate the “equation oriented” approach as well as the “sequential modular” approach to solving complex flowsheets for steady state applications. The applications include the Williams-Otto plant, the hydrodealkylation (HDA) of toluene, conversion of ethylene to ethanol and a bio-ethanol process.......This chapter covers the basic principles of steady state modelling and simulation using a number of case studies. Two principal approaches are illustrated that develop the unit operation models from first principles as well as through application of standard flowsheet simulators. The approaches...

  7. Switching Processes in Queueing Models

    CERN Document Server

    Anisimov, Vladimir V

    2008-01-01

    Switching processes, invented by the author in 1977, is the main tool used in the investigation of traffic problems from automotive to telecommunications. The title provides a new approach to low traffic problems based on the analysis of flows of rare events and queuing models. In the case of fast switching, averaging principle and diffusion approximation results are proved and applied to the investigation of transient phenomena for wide classes of overloading queuing networks.  The book is devoted to developing the asymptotic theory for the class of switching queuing models which covers  mode

  8. Research report of FY 1997 on the environmentally acceptable coal utilization system introduction support project. Follow-up project on circulating fluidized bed boiler introduction (Calaca Batangas Thermal Power Station); 1997 nendo chosa hokokusho. Kankyo chowagata sekitan riyo system donyu shien jigyo (junkan ryudosho boiler ni kakawaru follow up jigyo (Calaca Batangas karyoku hatsudensho))

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    For the follow-up project, to promote the diffusion of results of the clean coal technology (CCT) model projects, experts of circulating fluidized bed boilers were dispatched, to guide and advise for the operation of facilities introduced in these projects. The purpose of these projects is to diffuse the CCTs, and to support the promotion of environmental measures. Some guidance and advice about operation processes, data processing, operation regulation, maintenance, and boiler maintenance works were provided to the Ministry of Energy and Electric Power Corporation of the Philippines. Semirara, Malangas, and Samar coals in the Philippines were used for the tests. The boiler facilities could be operated by Philippine operators themselves. Based on the guidance and advice about operation processes, combustion tests using various Philippine coals were also planned and conducted by themselves. The maintenance techniques were transferred to Philippine operators through the inspection, repair and advice. The Philippine side understood the technologies well, and the circulating fluidized bed boiler technology was independently educated in the Philippines. 23 figs., 16 tabs.

  9. Research of Boiler Combustion Regulation for Reducing Nox Emission and its Effect on Boiler Efficiency

    Institute of Scientific and Technical Information of China (English)

    WANG Xue-dong; LUAN Tao; CHENG Lin; XIAO Kun

    2007-01-01

    The effect of boiler combustion regulation on Nox emission of two 1025t/h boilers has been studied. The researches show that Nox emission is influenced by coal species, operation conditions, etc, and can be reduced by regulating the combustion conditions. The effect of combustion regulation on boiler efficiency has also been checked.

  10. Assessment of the potential for conversion of TP-108 boilers to firing natural gas and fuel oil

    Science.gov (United States)

    Tugov, A. N.; Supranov, V. M.; Izyumov, M. A.; Vereshchetin, V. A.; Usman, Yu. M.; Natal'in, A. S.

    2017-03-01

    TP-108 boilers were initially designed to burn milled peat. In the 1980s, they were reconstructed for conversion to burning natural gas as well. However, operation of these boilers revealed problems due to low reheat temperature and great air inleakage in the furnace. The initial design of the boiler and its subsequent reconstruction are described in the paper. Measures are presented for further modernization of TP-108 boilers to eliminate the above-mentioned problems and enable natural gas or fuel oil only to be burned in them. Thermal design calculations made using a specially developed adapted model (AM) suggest that replacement of the existing burners with new oil/gas burners, installation of steam-to-steam heat exchangers (SSHE), and sealing of the boiler gas path to make it gas tight will allow the parameters typical of gas-and-oil fired boilers to be attained. It is demonstrated that SSHEs can yield the design secondary steam reheat temperature, although this solution is not typical for natural circulation boilers with steam reheat. The boiler equipped with SSHEs can operate on fuel oil or natural gas with flue gas recirculation or without it. Moreover, operation of the boiler with flue gas recirculation to the air duct in combination with staged combustion enables the required environmental indicators to be attained.

  11. Combustion Process Modelling and Control

    Directory of Open Access Journals (Sweden)

    Vladimír Maduda

    2007-10-01

    Full Text Available This paper deals with realization of combustion control system on programmable logic controllers. Control system design is based on analysis of the current state of combustion control systems in technological device of raw material processing area. Control system design is composed of two subsystems. First subsystem is represented by software system for measured data processing and for data processing from simulation of the combustion mathematical model. Outputs are parameters for setting of controller algorithms. Second subsystem consists from programme modules. The programme module is presented by specific control algorithm, for example proportional regulation, programmed proportional regulation, proportional regulation with correction on the oxygen in waste gas, and so on. According to the specific combustion control requirements it is possible built-up concrete control system by programme modules. The programme modules were programmed by Automation studio that is used for development, debugging and testing software for B&R controllers.

  12. Influence of additives on selective noncatalytic reduction of nitric oxide with ammonia in circulating fluidized bed boilers

    DEFF Research Database (Denmark)

    Leckner, Bo; Karlsson, Maria; Dam-Johansen, Kim

    1991-01-01

    realistic conditions in a research boiler and reaction kinetic calculations show that the type of additives used did not improve the process. On the other hand, it is shown that ammonia injection as such, when employed before the cyclone of the boiler, effectively reduces the NO emission to a level of 20...

  13. 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.

  14. A Method for Determining the Usability Potential of Ship Steam Boilers

    Directory of Open Access Journals (Sweden)

    Muślewski Łukasz

    2016-12-01

    Full Text Available Ship large-power steam boiler may serve as an example of complex critical technical system. A basis for rational control of operation of such system is knowledge on its capability of fulfilling the tasks to which it was intended. In order to make it possible to apply computer aiding to operational decision-making the capability should be described analytically. In this paper it was proposed to express the capability of ship steam boiler ( considered a complex system to perform service tasks, by calculating components of its usability potential in a given instant t. To this end , was distinguished a set of steam boiler fundamental features which formulate space of its technical states. Values and characteristic intervals of the features were defined and this way sub-spaces of serviceability and non-serviceability states of the object in question were determined. Next, in the considered space, technical state of the boiler and its usability potential was determined. Owing to this it become possible to quantitatively express the steam boiler functioning capability which served as a basis for elaborating an algorithm for controlling the operational processes of a complex technical system under action. In this paper is also described a way of application of the presented method to calculation of ship steam boiler usability potential, which may be especially instrumental in the case of operational control of the boilers of the kind , equipped with interstage reheaters, i.e. those operating with high values of operational parameters.

  15. Economic Analysis for Rebuilding of an Aged Pulverized Coal-Fired Boiler with a New Boiler in an Aged Thermal Power Plant

    Directory of Open Access Journals (Sweden)

    Burhanettin Cetin

    2013-01-01

    Full Text Available Fossil-fired thermal power plants (TPP produce a significant part of electricity in the world. Because of the aging TPPs and so their equipment (especially boiler, thermal power plants also produce less power than their installed capacities, and there has been power loss in time. This situation affects the supply and demand balance of countries. For this reason, aging equipments such as pulverized coal-fired boiler (PCB must be renewed and power loss must be recovered, instead of building new TPPs. In this study, economic analysis of rebuilding an aged pulverized coal-fired boiler with a new pulverized coal-fired boiler including flue gas desulfurization (FGD unit and a circulating fluidized bed boiler (FBB are investigated in an existing old TPP. Emission costs are also added to model, and the developed model is applied to a 200 MWe pulverized coal-fired thermal power plant in Turkey. As a result, the payback period and the net present value are calculated for different technical and economic parameters such as power loss, load factor, electricity price, discount rate, and escalation rate by using the annual value method. The outcomes of this study show that rebuilding of a pulverized coal-fired boiler with a new one is amortized itself in a very short time.

  16. Tuning of PID controllers for boiler-turbine units.

    Science.gov (United States)

    Tan, Wen; Liu, Jizhen; Fang, Fang; Chen, Yanqiao

    2004-10-01

    A simple two-by-two model for a boiler-turbine unit is demonstrated in this paper. The model can capture the essential dynamics of a unit. The design of a coordinated controller is discussed based on this model. A PID control structure is derived, and a tuning procedure is proposed. The examples show that the method is easy to apply and can achieve acceptable performance.

  17. Conversion of KVGM-100-150 boilers to cyclone-swirl burning of gas

    Science.gov (United States)

    Shtym, K. A.; Solov'eva, T. A.

    2015-03-01

    Heating sources of Vladivostok with boilers reconstructed in 2011 to gas burning is presented. The historical reference of the experience of boiler conversion to cyclone-swirl technology of burning of fuel oil and gas is given. Stages of the primary furnace and boiler upgrading are shown. Taking BKZ 75-16 and BKZ-120-100 boilers as examples, the principal differences of the swirl type of fuel burning from the burner type are demonstrated. Data of the KVGM-100-150 MTs boiler with cyclone-swirl burning of gas and fuel oil is represented. The mathematical model developed for the primary furnace with the 65 MW capacity gives detailed explanations to the features of mixing in the combustion chamber of the primary furnace, which substantiate conditions and places of the fuel injection. The practical result is supported by test data obtained on the operating equipment. To enhance the effectiveness of fuel consumption on six converted KVGM-100-150 MTs boilers, the convective section was restructured and the water circulation circuit was optimized. Comparative analysis of estimated and operating characteristics showed the efficiency increment. The application of cyclone-swirl technology made it possible to increase the effectiveness of the KVGM-100-150 boiler and improve its environmental indicators.

  18. Possibility analysis of combustion of torrefied biomass in 140 t/h PC boiler

    Directory of Open Access Journals (Sweden)

    Jagodzińska Katarzyna

    2016-01-01

    Full Text Available The study attempts to evaluate the impact of combustion of torrefied willow (Latin: Salix viminalis and palm kernel shell (Latin: Elaeis guineensis on the heat exchange in a 140 t/h PC boiler through an analysis of 6 cases for different boiler loads (60 %, 75 % and 100 % and a comparison with coal combustion. The analysis is premised on a 0-dimensional model based on the method presented in [15, 16, 17] and long-standing experimental measurements. Inter alia, the following results are presented: the temperature distribution of flue gases and the working medium (water/steam in characteristic points of the boiler as well as heat transfer coefficients for each element thereof. The temperature distribution of both fluids and the heat transfer coefficients are similar for all analysed fuels for each boiler load. However, the flue gas temperature at the outlet is higher in the case of torrefied biomass combustion. Due to that, there is an increase in the stack loss, which involves a decrease in the boiler efficiency. The conclusion is that torrefied biomass combustion is possible in a PC boiler without the need to change the boiler construction. However, it would be less effective than coal combustion.

  19. Mathematical modeling of biological processes

    CERN Document Server

    Friedman, Avner

    2014-01-01

    This book on mathematical modeling of biological processes includes a wide selection of biological topics that demonstrate the power of mathematics and computational codes in setting up biological processes with a rigorous and predictive framework. Topics include: enzyme dynamics, spread of disease, harvesting bacteria, competition among live species, neuronal oscillations, transport of neurofilaments in axon, cancer and cancer therapy, and granulomas. Complete with a description of the biological background and biological question that requires the use of mathematics, this book is developed for graduate students and advanced undergraduate students with only basic knowledge of ordinary differential equations and partial differential equations; background in biology is not required. Students will gain knowledge on how to program with MATLAB without previous programming experience and how to use codes in order to test biological hypothesis.

  20. Numerical prediction of the chemical composition of gas products at biomass combustion and co-combustion in a domestic boiler

    Directory of Open Access Journals (Sweden)

    Radomiak Henryk

    2017-01-01

    Full Text Available In recent years the numerical modelling of biomass combustion has been successfully applied to determine the combustion mechanism and predict its products. In this study the influence of the addition of waste glycerin in biomass wood pellets on the chemical composition of exhaust gases has been investigated. The pellets have been prepared from spruceand pine wood sawdust without and with addition of waste glycerin. The waste glycerol is a undesirable by-product of biodiesel transesterification at oil manufacturing. The produced pellets were being burned in the 10 kW domestic boiler adapted to wood pellets combustion. The possibilities of pollutants generation (CO2, CO, NOx SOx and compounds containing chlorine in the exhaust gases coming from the boiler were numerically calculated using the latest version of CHEMKIN-PRO software, introduced by the American company Reaction Design. The results of the calculations correspond to the data obtained on a real object, in particular: combustion temperature, gas pressure, residence time of fuel in the burner, air flow, fuel consumption, as well as elementary composition of fuel supplied into the boiler. The proposed method of predicting the chemical composition of exhaust gases allows proper control of the combustion process and can be considered as an important step in reducing the pollutants (lower emission of NOx, SOx and CO2 neutral and thus to contribute to the improvement of the environmental quality. In addition, knowledge of the amounts of Clbased compounds produced in combustion process (under given conditions, can serve as an important hint in terms of corrosion prevention of boiler- and chimney steels.

  1. Principles of polymer processing modelling

    Directory of Open Access Journals (Sweden)

    Agassant Jean-François

    2016-01-01

    Full Text Available Polymer processing involves three thermo-mechanical stages: Plastication of solid polymer granules or powder to an homogeneous fluid which is shaped under pressure in moulds or dies and finally cooled and eventually drawn to obtain the final plastic part. Physical properties of polymers (high viscosity, non-linear rheology, low thermal diffusivity as well as the complex shape of most plastic parts make modelling a challenge. Several examples (film blowing extrusion dies, injection moulding, blow moulding are presented and discussed.

  2. Boiler corrosion. Corrosion of boilers at low boiler water temperatures. Heizkessel-Korrosion. Korrosion von Heizkesseln bei tiefen Kesselwassertemperaturen

    Energy Technology Data Exchange (ETDEWEB)

    Koebel, M.; Elsener, M.

    1989-02-01

    Thermostatic cast iron and steel 35.8 specimens were inserted between the fire tubes of a test boiler and exposed to flue gases for a period of three weeks. The corrosion rates at material temperatures between 20 and 60deg C as well as the effects of continuous and intermittent boiler operation were determined. Details are given on the specimens alloying constituents, the testing and test conditions (schematic representation of the experimental set-up). Diagrams and tables facilitate access to test results informing about corrosion rates and corrosion product structure analyses for continuous burner operation. While low boiler water temperatures (below 60deg C in the case of extra light heating oils) are found to necessarily involve higher risks and shorter boiler service lives, low flue gas temperatures alone are considered not to be increasing the risk of boiler corrosion. (HWJ).

  3. Recovery Act: Oxy-Combustion Techology Development for Industrial-Scale Boiler Applications

    Energy Technology Data Exchange (ETDEWEB)

    Levasseur, Armand

    2014-04-30

    matrix of fuels, oxyprocess variables and boiler design parameters. Significant improvement of CFD modeling tools and validation against 15 MWth experimental data has been completed. Oxy-boiler demonstration and large reference designs have been developed, supported with the information and knowledge gained from the 15 MWth testing. The results from the 15 MWth testing in the BSF and complimentary bench-scale testing are addressed in this volume (Volume II) of the final report. The results of the modeling efforts (Volume III) and the oxy boiler design efforts (Volume IV) are reported in separate volumes.

  4. Reduction efficiency prediction of CENIBRA's recovery boiler by direct minimization of gibbs free energy

    OpenAIRE

    W. L. Silva; Ribeiro,J. C. T.; E. F.da Costa Jr; A. O. S.da Costa

    2008-01-01

    The reduction efficiency is an important variable during the black liquor burning process in the Kraft recovery boiler. This variable value is obtained by slow experimental routines and the delay of this measure disturbs the pulp and paper industry customary control. This paper describes an optimization approach for the reduction efficiency determination in the furnace bottom of the recovery boiler based on the minimization of the Gibbs free energy. The industrial data used in this study were...

  5. Integrated modelling in materials and process technology

    DEFF Research Database (Denmark)

    Hattel, Jesper Henri

    2008-01-01

    Integrated modelling of entire process sequences and the subsequent in-service conditions, and multiphysics modelling of the single process steps are areas that increasingly support optimisation of manufactured parts. In the present paper, three different examples of modelling manufacturing...... processes from the viewpoint of combined materials and process modelling are presented: solidification of thin walled ductile cast iron, integrated modelling of spray forming and multiphysics modelling of friction stir welding. The fourth example describes integrated modelling applied to a failure analysis...

  6. 新颖船舶燃油锅炉模拟实验系统的研制%An Original Simulation Experiment System of Marine Fuel Boiler

    Institute of Scientific and Technical Information of China (English)

    严华; 杨文中

    2012-01-01

    For marine fuel boiler control object of pluralism, on the basis of introduction for its composition and functions, the paper builds a new experimental simulation system of marine fuel boiler In order to realistically reflect the working principle and processes, the boiler body and simulation physical modeling of boiler control box are established with a combustion and water level signal detection circuit. A combustion and water level control process is programmed by PLC. Practical applications verify the feasibility of the system, and resolved the problems in the teaching of ship fuel boiler%针对船舶燃油辅锅炉控制对象的多元性,在简要介绍其组成及功能的基础上,构建了一种新颖的船舶燃油锅炉实验模拟系统。为了逼真反映船舶燃油锅炉工作原理和工作过程,建立了锅炉本体及燃油锅炉控制箱的仿真实物模型,设计了燃烧、水位信号检测电路,利用PLC开发燃烧过程和水位控制程序。实际应用验证了该模拟系统的可行性,解决了船舶燃油锅炉教学上的难题。

  7. A Review of Process Modeling Language Paradigms

    Institute of Scientific and Technical Information of China (English)

    MA Qin-hai; GUAN Zhi-min; LI Ying; ZHAO Xi-nan

    2002-01-01

    Process representation or modeling plays an important role in business process engineering.Process modeling languages can be evaluated by the extent to which they provide constructs useful for representing and reasoning about the aspects of a process, and subsequently are chosen for a certain purpose.This paper reviews process modeling language paradigms and points out their advantages and disadvantages.

  8. 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...

  9. Business Process Modelling for Measuring Quality

    NARCIS (Netherlands)

    Heidari, F.; Loucopoulos, P.; Brazier, F.M.

    2013-01-01

    Business process modelling languages facilitate presentation, communication and analysis of business processes with different stakeholders. This paper proposes an approach that drives specification and measurement of quality requirements and in doing so relies on business process models as

  10. Business Process Modelling for Measuring Quality

    NARCIS (Netherlands)

    Heidari, F.; Loucopoulos, P.; Brazier, F.M.

    2013-01-01

    Business process modelling languages facilitate presentation, communication and analysis of business processes with different stakeholders. This paper proposes an approach that drives specification and measurement of quality requirements and in doing so relies on business process models as represent

  11. COAL COMBUSTION EFFICIENCY IN CFB BOILER

    Institute of Scientific and Technical Information of China (English)

    Hairui Yang; Guangxi Yue

    2005-01-01

    The carbon content in the fly ash from most Chinese circulating fluidized bed (CFB) boilers is much higher than expected, thus directly influencing the combustion efficiency. In the present paper, carbon burnout was investigated both in field tests and laboratory experiments. The effect of coal property, operation condition, gas-solid mixing, char deactivation,residence time and cyclone performance are analyzed seriatim based on large amount of experimental results.A coal index is proposed to describe the coal rank, defined by the ratio of the volatile content to the coal heat value, is a useful parameter to analyze the char burnout. The carbon content in the fly ash depends on the coal rank strongly. CFB boilers burning anthracite, which has low coal index, usually have high carbon content in the fly ash. On the contrary, the CFB boilers burning brown coal, which has high coal index, normally have low carbon content.Poor gas-solid mixing in the furnace is another important reason of the higher carbon content in the fly ash. Increasing the velocity and rigidity of the secondary air could extend the penetration depth and induce more oxygen into the furnace center. Better gas solid mixing will decrease the lean oxygen core area and increase char combustion efficiency.The fine char particles could be divided into two groups according to their reactivity. One group is "fresh" char particles with high reactivity and certain amount of volatile content. The other group of char particles has experienced sufficient combustion time both in the furnace and in the cyclone, with nearly no volatile. These "old" chars in the fly ash will be deactivated during combustion of large coal particles and have very low carbon reactivity. The generated fine inert char particles by attrition of large coal particles could not easily burn out even with the fly ash recirculation. The fraction of large coal particles in coal feed should be reduced during fuel preparation process.The cyclone

  12. Mechanistic Model for Ash Deposit Formation in Biomass Suspension-Fired Boilers. Part 2: Model Verification by Use of Full Scale Tests

    DEFF Research Database (Denmark)

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

    2017-01-01

    describes particle sticking or rebound by a combination of the description of (visco)elsatic particles impacting a solid surface and particle capture by a viscous surface. The model is used to predict deposit formation rates measured during tests conducted with probes in full-scale suspension-fired biomass...... of some physical parameters related to the description of surface capture are suggested. Based on these examinations of the model ability to describe observed deposit formation rates, the proposed model can be regarded as a promising tool for description of deposit formation in full-scale biomass......A model for deposit formation in suspension firing of biomass has been developed. The model describes deposit build-up by diffusion and subsequent condensation of vapors, thermoforesis of aerosols, convective diffusion of small particles, impaction of large particles and reaction. The model...

  13. Development of Fuzzy Controller for Water Level in Stream Boiler Tank

    Directory of Open Access Journals (Sweden)

    Surachai Panich

    2010-01-01

    Full Text Available Problem statement: The process control of steam boiler is very popular used in the industrial. The temperature of the water is transferred directly by electrical heater. The pressure will increase based on the changing of the temperature. The purpose of the control is to change the opening set point for the valve when the temperature and pressure in the tank are changed. For this problem, we develop fuzzy algorithm to adjust the optimal percentage of valve open. Approach: In this study, the fuzzy control application was programmed in fuzzy control language in form of the function block using structure control language. The input information consisted of real variables in the form of measurable process variables, as well as set points. And the output variables were real variables in the form of correcting variables. Results: The fuzzy control was developed, which consists of two input variables, the degree of temperature and pressure in boiler tank measured by sensor. For fuzzy system of water level control, the algorithm is basically implemented in form of the MATLAB code. In the experiment, we assumed that the water level would not effect to the temperature and pressure. Conclusion: The research for the development of the fuzzy logic and the model was tested with the step inputs and the changing of the inputs. The whole simulation process was built to test the behavior of the system when the inputs change.

  14. Discussion and Analysis of the Causes of Accident of Steam Boiler Tube Rupture and the Processing Methods%蒸汽锅炉爆管事故原因及处理方法探讨分析

    Institute of Scientific and Technical Information of China (English)

    李伟忠; 安文广; 张丽波

    2012-01-01

    蒸汽锅炉在运行过程中,一旦发生爆管事故,会损坏邻近的管壁,冲塌炉墙,并且在很短的时间造成锅炉严重缺水,使事故扩大,因此须保证安全可靠,确保安全生产运行.本文主要探讨蒸汽锅炉运行中锅炉爆管事故原因及处理方法.%Once the accident of tube rupture for steam boiler during operation happened, it can damage the nearby tube wall, and collapse furnace wall, resulting in serious water shortages for boiler in a very short period of time, expanding the accident, therefore, we must ensure the safety and reliability, safe production and operation. This paper mainly discusses the causes and treatment methods of accident of boiler tube rupture in the operation of steam boiler.

  15. Numerical investigation on the flow, combustion, and NOX emission characteristics in a 660 MWe tangential firing ultra-supercritical boiler

    Directory of Open Access Journals (Sweden)

    Wenjing Sun

    2016-02-01

    Full Text Available A three-dimensional numerical simulation was carried out to study the pulverized-coal combustion process in a tangentially fired ultra-supercritical boiler. The realizable k-ε model for gas coupled with discrete phase model for coal particles, P-1 radiation model for radiation, two-competing-rates model for devolatilization, and kinetics/diffusion-limited model for combustion process are considered. The characteristics of the flow field, particle motion, temperature distribution, species components, and NOx emissions were numerically investigated. The good agreement of the measurements and predictions implies that the applied simulation models are appropriate for modeling commercial-scale coal boilers. It is found that an ideal turbulent flow and particle trajectory can be observed in this unconventional pulverized-coal furnace. With the application of over-fire air and additional air, lean-oxygen combustion takes place near the burner sets region and higher temperature at furnace exit is acquired for better heat transfer. Within the limits of secondary air, more steady combustion process is achieved as well as the reduction of NOx. Furthermore, the influences of the secondary air, over-fire air, and additional air on the NOx emissions are obtained. The numerical results reveal that NOx formation attenuates with the decrease in the secondary air ratio (γ2nd and the ratio of the additional air to the over-fire air (γAA/γOFA was within the limits.

  16. Pilot-Scale Demonstration of a Novel, Low-Cost Oxygen Supply Process and its Integration with Oxy-Fuel Coal-Fired Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Krish Krishnamurthy; Divy Acharya; Frank Fitch

    2008-09-30

    In order to achieve DOE targets for carbon dioxide capture, it is crucial not only to develop process options that will generate and provide oxygen to the power cycle in a cost-effective manner compared to the conventional oxygen supply methods based on cryogenic air separation technology, but also to identify effective integration options for these new technologies into the power cycle with carbon dioxide capture. The Linde/BOC developed Ceramic Autothermal Recovery (CAR) process remains an interesting candidate to address both of these issues by the transfer of oxygen from the air to a recycled CO{sub 2} rich flue-gas stream in a cyclic process utilizing the high temperature sorption properties of perovskites. Good progress was made on this technology in this project, but significant challenges remain to be addressed before CAR oxygen production technology is ready for commercial exploitation. Phase 1 of the project was completed by the end of September 2008. The two-bed 0.7 tons/day O2 CAR process development unit (PDU) was installed adjacent to WRI's pilot scale coal combustion test facility (CTF). Start-up and operating sequences for the PDU were developed and cyclic operation of the CAR process demonstrated. Controlled low concentration methane addition allowed the beds to be heated up to operational temperature (800-900 C) and then held there during cyclic operation of the 2-bed CAR process, in this way overcoming unavoidable heat losses from the beds during steady state operation. The performance of the PDU was optimized as much as possible, but equipment limitations prevented the system from fully achieving its target performance. Design of the flue gas recirculation system to integrate CAR PDU with the CTF and the system was completed and integrated tests successfully performed at the end of the period. A detailed techno-economic analysis was made of the CAR process for supplying the oxygen in oxy-fuel combustion retrofit option using AEP's 450

  17. Thermal Efficiency of Power Module “Boiler with Solar Collectors as Additional Heat Source” For Combined Heat Supply System

    Directory of Open Access Journals (Sweden)

    Denysova A.E.

    2015-04-01

    Full Text Available The purpose of work is to increase the efficiency of the combined heat supply system with solar collectors as additional thermal generators. In order to optimize the parameters of combined heat supply system the mathematical modeling of thermal processes in multi module solar collectors as additional thermal generators for preheating of the water for boiler have been done. The method of calculation of multi-module solar collectors working with forced circulation for various configurations of hydraulic connection of solar collector modules as the new result of our work have been proposed. The results of numerical simulation of thermal efficiency of solar heat source for boiler of combined heat supply system with the account of design features of the circuit; regime parameters of thermal generators that allow establishing rational conditions of its functioning have been worked out. The conditions of functioning that provide required temperature of heat carrier incoming to boiler and value of flow rate at which the slippage of heat carrier is not possible for different hydraulic circuits of solar modules have been established.

  18. Reduction efficiency prediction of CENIBRA's recovery boiler by direct minimization of gibbs free energy

    Directory of Open Access Journals (Sweden)

    W. L. Silva

    2008-09-01

    Full Text Available The reduction efficiency is an important variable during the black liquor burning process in the Kraft recovery boiler. This variable value is obtained by slow experimental routines and the delay of this measure disturbs the pulp and paper industry customary control. This paper describes an optimization approach for the reduction efficiency determination in the furnace bottom of the recovery boiler based on the minimization of the Gibbs free energy. The industrial data used in this study were directly obtained from CENIBRA's data acquisition system. The resulting approach is able to predict the steady state behavior of the chemical composition of the furnace recovery boiler, - especially the reduction efficiency when different operational conditions are used. This result confirms the potential of this approach in the analysis of the daily operation of the recovery boiler.

  19. 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.

  20. PAH emission from the industrial boilers.

    Science.gov (United States)

    Li, C; Mi, H; Lee, W; You, W; Wang, Y

    1999-10-01

    Polycyclic aromatic hydrocarbons (PAHs) emitted from 25 industrial boilers were investigated. The fuels used for these 25 boilers included 21 heavy oil, two diesel, a co-combustion of heavy oil and natural gas (HO+NG) and a co-combustion of coke oven gas and blast furnace gas (COG+BFG) boilers. PAH samples from the stack flue gas (gas and particle phases) of these 25 boilers were collected by using a PAH stack sampling system. Twenty one individual PAHs were analyzed primarily by a gas chromatography/mass spectrometer (GC/MS). Total-PAH concentration in the flue gas of 83 measured data for these 25 boiler stacks ranged between 29.0 and 4250 microg/m(3) and averaged 488 microg/m(3). The average of PAH-homologue mass (F%) counted for the total-PAH mass was 54.7%, 9.47% and 15.3% for the 2-ring, 3-ring and 4-ring PAHs, respectively. The PAHs in the stack flue gas were dominant in the lower molecular weight PAHs. The emission factors (EFs) of total-PAHs were 13,300, 2920, 2880 and 208 microg/kg-fuel for the heavy oil, diesel, HO+NG and COG+BFG fueled-boiler, respectively. Nap was the most predominant PAH occurring in the stack flue gas. In addition, the EF of 21 individual PAHs in heavy-oil boiler were almost the highest among the four various fueled-boilers except for those of FL and BkF in the diesel boiler. Furthermore, the EF of total-PAHs or BaP for heavy oil were both one order of magnitude higher than that for the diesel-fueled boiler.

  1. Value analysis of district heating system with gas-fired peak load boiler in secondary network

    Institute of Scientific and Technical Information of China (English)

    郑雪晶; 穆振英

    2009-01-01

    In district heating(DH) system with gas-fired peak load regulating boiler in the secondary network,by prolonging run time of base load plants under rated condition,the mean energy efficiency could be increased. The fuels of the system,including coal and gas,would cause different environmental impacts. Meanwhile,the reliability of the heating networks would be changed because the peak load regulating boiler could work as a standby heat source. A model for assessment of heating system was established by value analysis to optimize this kind of system. Energy consumption,greenhouse gas emission,pollution emission and system reliability were selected as functional assessment indexes in the model. Weights of each function were determined by analytical hierarchy process (AHP) and experts consultation. Life cycle cost was used as the cost in the model. A real case as an example was discussed to obtain the optimal base load ratio. The result shows that the optimal base load ratio of the case is 0.77.

  2. 600MW亚临界汽包炉炉水处理工艺优化试验%Optimized experiments on the boiler-water treatment method of 600 MW sub-critical boiler unit

    Institute of Scientific and Technical Information of China (English)

    星成霞; 王应高; 李永立; 金绪良; 周子龙

    2012-01-01

    The boiler-water treatment method of 600 MW sub-critical boiler unit has direct influence on its steam quality. It is important to optimize the boiler-water treatment method in order to improve boiler steam quality and prevent salt deposits on steam turbine. Based on experiments, the effect of phosphate concentration in the boiler water of several 600 MW sub-critical boilers of the same type on steam quality has been investigated quantitatively. The optimal boiler-water treatment process of every unit and corresponding boiler-water quality controlling scheme are determined.%600MW亚临界汽包炉炉水的处理方式影响机组的蒸汽品质,优化炉水处理工工艺对于提高锅炉蒸汽品质、预防汽轮机积盐具有重要作用.通过试验定量考察了数台同型号600 MW亚临界汽包炉炉水磷酸盐含量对蒸汽品质的影响,确定了各机组最优的炉水处理工艺及炉水水质监控指标最优控制方案.

  3. Development of Square Coal Tube in Boiler%方型锅炉落煤筒的研制

    Institute of Scientific and Technical Information of China (English)

    高平; 王婵; 郭在在; 付利涛; 兰兰; 邸建辉; 闫志飞; 田迎春; 郭永亮

    2014-01-01

    Aimed at the reasons for the early deformation in service and cracking failure of the welding-manufactured square tubes in coal boiler,a lost foam casting process scheme for the square tubes in coal boiler was put forward,and some measures were adopted,such as designing a "well" shape deformation brace,increasing casting chamfering radius,adjusting chemical composition of the material,and so on.The production process for the square tubes in coal boiler were introduced,including lost foam casting process,melting and pouring process,model making and coating process,and model packing process.Practice proves that the service life of the cast square tubes is 1.6 times of welding tubes,which effectively improve the efficiency of transporting coal and the enterprise economic benefit.%针对焊接制造锅炉落煤筒服役早期出现变形和开裂失效的原因,提出了消失模铸造落煤筒的方案,并采取了设计“井”形防变形拉筋,加大铸件铸造倒角半径,调整优化材料的化学成分等措施.同时介绍了消失模铸造落煤筒的熔炼、浇注、模型制作、涂料涂刷和模型装箱等工艺.实践证明,研制的落煤筒使用寿命是焊接制造的1.6倍,有效地提高输煤效率和企业的经济效益.

  4. Developing engineering processes through integrated modelling of product and process

    DEFF Research Database (Denmark)

    Nielsen, Jeppe Bjerrum; Hvam, Lars

    2012-01-01

    This article aims at developing an operational tool for integrated modelling of product assortments and engineering processes in companies making customer specific products. Integrating a product model in the design of engineering processes will provide a deeper understanding of the engineering...... activities as well as insight into how product features affect the engineering processes. The article suggests possible ways of integrating models of products with models of engineering processes. The models have been tested and further developed in an action research study carried out in collaboration...

  5. Kinetic Modeling and Isotherm Studies for Copper(II Adsorption onto Palm Oil Boiler Mill Fly Ash (POFA as a Natural Low-Cost Adsorbent

    Directory of Open Access Journals (Sweden)

    Abdul Shukor Abdul Aziz

    2013-11-01

    Full Text Available Adsorption characteristics of palm oil boiler mill fly ash (POFA for the removal of Cu(II from aqueous solution were investigated using batch adsorption studies. The effects of relevant parameters such as contact time, solution pH, adsorbent dosage, and initial concentration of copper were examined. Fundamental batch investigations indicated that 90% of the Cu(II was removed in the first 30 min, achieving equilibration after only 270 min of agitation. The Cu(II uptake mechanism is particularly pH- and concentration-dependant, favoring a pH value of 6.0. A decrease in adsorption capacity (qe with an increase in Cu(II removal efficiency (RE % was obtained as the adsorbent dosage increased. The adsorption behavior of Cu(II fit well to the Langmuir isotherm, with a monolayer adsorption capacity of 17 mg/g. The applicability of the Langmuir isotherm suggested the formation of monolayer coverage of Cu(II ions onto equivalent sites of the adsorbent. Kinetics experimental data followed the trend of pseudo second-order kinetics, which is consistent with chemisorption with intraparticle diffusion as one of the rate-determining steps. Therefore, this study indicates that POFA could be used successfully as a natural low-cost adsorbent for Cu(II removal from aqueous solutions.

  6. Safety conditions of steam boilers in companies associated with a professional risk administration company in Antioquia, 2009

    Directory of Open Access Journals (Sweden)

    Diego L. Sepúlveda M

    2011-07-01

    Full Text Available Objective: to determine the safety conditions of steam boilers in companies associated with a professional risk administra-tion company in Antioquia, Colombia. To this end, their op-eration conditions shall be characterized, the associated risks identified, and their safety level assessed. Methodology:. a descriptive crosssectional study was carried out in twenty companies whose production processes involve boilers. A survey on the conditions for operation was applied on both the maintenance managers and the boilers’ operators in each company. A hazard risk assessment matrix was made as in-structed in the GTC-45 Colombian technical guide, and an assessment instrument was applied to determine the safety level for each boiler. Results: 70% of the assessed boilers obtained a low score (less than 65 points according to the scale, which has been validated by experts; the remaining boilers obtained an acceptable score (66 to 81 points. It was also found that 85% of the boilers had no operating instructions, and 60% of them did not have any kind of alarm. Conclusions: the stud-ied boilers had poor security conditions, mainly related to the absence of operation protocols, boiler operator training, and poor supervision by competent authorities

  7. 49 CFR 230.36 - Hydrostatic testing of boilers.

    Science.gov (United States)

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Pressure Testing of Boilers § 230.36 Hydrostatic testing of boilers. (a) Time of test. The... 49 Transportation 4 2010-10-01 2010-10-01 false Hydrostatic testing of boilers. 230.36 Section...

  8. 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)...

  9. 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...

  10. 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....

  11. 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...

  12. 10 CFR 431.82 - Definitions concerning commercial packaged boilers.

    Science.gov (United States)

    2010-01-01

    ... COMMERCIAL AND INDUSTRIAL EQUIPMENT Commercial Packaged Boilers § 431.82 Definitions concerning commercial...). Commercial packaged boiler means a type of packaged low pressure boiler that is industrial equipment with a... 10 Energy 3 2010-01-01 2010-01-01 false Definitions concerning commercial packaged boilers....

  13. 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.

  14. CHP Integrated with Burners for Packaged Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Castaldini, Carlo; Darby, Eric

    2013-09-30

    The objective of this project was to engineer, design, fabricate, and field demonstrate a Boiler Burner Energy System Technology (BBEST) that integrates a low-cost, clean burning, gas-fired simple-cycle (unrecuperated) 100 kWe (net) microturbine (SCMT) with a new ultra low-NOx gas-fired burner (ULNB) into one compact Combined Heat and Power (CHP) product that can be retrofit on new and existing industrial and commercial boilers in place of conventional burners. The Scope of Work for this project was segmented into two principal phases: (Phase I) Hardware development, assembly and pre-test and (Phase II) Field installation and demonstration testing. Phase I was divided into five technical tasks (Task 2 to 6). These tasks covered the engineering, design, fabrication, testing and optimization of each key component of the CHP system principally, ULNB, SCMT, assembly BBEST CHP package, and integrated controls. Phase I work culminated with the laboratory testing of the completed BBEST assembly prior to shipment for field installation and demonstration. Phase II consisted of two remaining technical tasks (Task 7 and 8), which focused on the installation, startup, and field verification tests at a pre-selected industrial plant to document performance and attainment of all project objectives. Technical direction and administration was under the management of CMCE, Inc. Altex Technologies Corporation lead the design, assembly and testing of the system. Field demonstration was supported by Leva Energy, the commercialization firm founded by executives at CMCE and Altex. Leva Energy has applied for patent protection on the BBEST process under the trade name of Power Burner and holds the license for the burner currently used in the product. The commercial term Power Burner is used throughout this report to refer to the BBEST technology proposed for this project. The project was co-funded by the California Energy Commission and the Southern California Gas Company (SCG), a

  15. modeling grinding modeling grinding processes as micro processes ...

    African Journals Online (AJOL)

    eobe

    workpiece material dynamics thus allowing for process planning, optimization, and control. In spite of the .... arrangement of the grain vertices at the wheel active surface. ...... on Workpiece Roughness and Process Vibration” J. of the Braz.

  16. Overview of the DOE studies of recovery boiler floor tube cracking

    Energy Technology Data Exchange (ETDEWEB)

    Keiser, J.R.; Taljat, B.; Wang, X.L. [and others

    1998-03-01

    Cracking of the stainless steel layer of coextruded 304L/SA210 recovery boiler floor tubes has been observed in an increasing number of black liquor recovery boilers. Because failure of such tubes is a serious safety concern as well as an economic issue, this project was initiated with the objective of identifying alternate materials or process changes that would prevent tube cracking. Tensile stresses are essential for the most likely failure mechanisms, i.e., fatigue or stress corrosion cracking, therefore stresses were measured at room temperature and modeling was used to predict stresses under operating conditions. Laboratory studies have identified conditions under which composite tubes crack due to thermal fatigue and stress corrosion. Floor tube temperature measurements have defined the magnitude and frequency of temperature fluctuations experienced by such tubes, and smelt corrosion studies have measured the degradation rate when molten smelt comes in contact with tubes. Based on these observations, certain materials appear more likely to resist cracking and certain process changes should help avoid conditions that cause composite tube cracking.

  17. Managing Analysis Models in the Design Process

    Science.gov (United States)

    Briggs, Clark

    2006-01-01

    Design of large, complex space systems depends on significant model-based support for exploration of the design space. Integrated models predict system performance in mission-relevant terms given design descriptions and multiple physics-based numerical models. Both the design activities and the modeling activities warrant explicit process definitions and active process management to protect the project from excessive risk. Software and systems engineering processes have been formalized and similar formal process activities are under development for design engineering and integrated modeling. JPL is establishing a modeling process to define development and application of such system-level models.

  18. Cupola Furnace Computer Process Model

    Energy Technology Data Exchange (ETDEWEB)

    Seymour Katz

    2004-12-31

    The cupola furnace generates more than 50% of the liquid iron used to produce the 9+ million tons of castings annually. The cupola converts iron and steel into cast iron. The main advantages of the cupola furnace are lower energy costs than those of competing furnaces (electric) and the ability to melt less expensive metallic scrap than the competing furnaces. However the chemical and physical processes that take place in the cupola furnace are highly complex making it difficult to operate the furnace in optimal fashion. The results are low energy efficiency and poor recovery of important and expensive alloy elements due to oxidation. Between 1990 and 2004 under the auspices of the Department of Energy, the American Foundry Society and General Motors Corp. a computer simulation of the cupola furnace was developed that accurately describes the complex behavior of the furnace. When provided with the furnace input conditions the model provides accurate values of the output conditions in a matter of seconds. It also provides key diagnostics. Using clues from the diagnostics a trained specialist can infer changes in the operation that will move the system toward higher efficiency. Repeating the process in an iterative fashion leads to near optimum operating conditions with just a few iterations. More advanced uses of the program have been examined. The program is currently being combined with an ''Expert System'' to permit optimization in real time. The program has been combined with ''neural network'' programs to affect very easy scanning of a wide range of furnace operation. Rudimentary efforts were successfully made to operate the furnace using a computer. References to these more advanced systems will be found in the ''Cupola Handbook''. Chapter 27, American Foundry Society, Des Plaines, IL (1999).

  19. Computer Aided Continuous Time Stochastic Process Modelling

    DEFF Research Database (Denmark)

    Kristensen, N.R.; Madsen, Henrik; Jørgensen, Sten Bay

    2001-01-01

    A grey-box approach to process modelling that combines deterministic and stochastic modelling is advocated for identification of models for model-based control of batch and semi-batch processes. A computer-aided tool designed for supporting decision-making within the corresponding modelling cycle...

  20. Process Correlation Analysis Model for Process Improvement Identification

    Directory of Open Access Journals (Sweden)

    Su-jin Choi

    2014-01-01

    software development process. However, in the current practice, correlations of process elements are often overlooked in the development of an improvement plan, which diminishes the efficiency of the plan. This is mainly attributed to significant efforts and the lack of required expertise. In this paper, we present a process correlation analysis model that helps identify correlations of process elements from the results of process assessment. This model is defined based on CMMI and empirical data of improvement practices. We evaluate the model using industrial data.

  1. A Process Model for Establishing Business Process Crowdsourcing

    Directory of Open Access Journals (Sweden)

    Nguyen Hoang Thuan

    2017-06-01

    Full Text Available Crowdsourcing can be an organisational strategy to distribute work to Internet users and harness innovation, information, capacities, and variety of business endeavours. As crowdsourcing is different from other business strategies, organisations are often unsure as to how to best structure different crowdsourcing activities and integrate them with other organisational business processes. To manage this problem, we design a process model guiding how to establish business process crowdsourcing. The model consists of seven components covering the main activities of crowdsourcing processes, which are drawn from a knowledge base incorporating diverse knowledge sources in the domain. The built model is evaluated using case studies, suggesting the adequateness and utility of the model.

  2. Fuzzy Control System for Hearth Pressure of Blast Furnace Gas Fired Boiler%全燃烧高炉煤气锅炉炉膛负压模糊控制系统

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      燃高炉煤气锅炉在燃料燃烧和运行方式上与传统的燃煤锅炉区别很大,使得燃煤锅炉控制方法不适用于燃高炉煤气锅炉。为提高炉膛负压控制精度,引入了模糊控制策略对炉膛负压进行控制。采用炉压偏差及偏差变化率作为模糊控制器的输入变量,仿真研究表明,经模糊控制器控制的炉膛负压稳定性较采用 PID控制方法有显著提高,更适合于炉膛压力的控制。%There is a great difference between blast furnace gas fired boiler and coal fired boiler in the fuel combustion process and the method of operation ,so the control model for coal fired boiler can not be applicable for blast furnace gas fired boiler .To increase the control accuracy of negative pressure in hearth ,a fuzzy control strategy was applied to the negative pressure control ,which used the deviation and deviation variance ratio of combustion chamber draft as the input variables of fuzzy controller .The results of simulation indicate that the stability of negative pressure in boiler is greatly improved by fuzzy PID control compared with traditional PID control ,so it can meet the control requirement of boiler negative pressure .

  3. A method for exergy analysis of sugar cane bagasse boilers

    Energy Technology Data Exchange (ETDEWEB)

    Cortez, L.A.B.; Gomez, E.O. [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Agricola

    1998-03-01

    This work presents a method to conduct a thermodynamic analysis of sugarcane bagasse boilers. The method is based on the standard and actual reactions which allows the calculation of the enthalpies of each process subequation and the exergies of each of the main flowrates participating in the combustion. The method is presented using an example with real data from a sugarcane bagasse boiler. A summary of the results obtained is also presented together based on the 1 st Law of Thermodynamics analysis, the exergetic efficiencies, and the irreversibility rates. The method presented is very rigorous with respect to data consistency, particularly for the flue gas composition. (author) 11 refs., 1 fig., 6 tabs.; e-mail: cortez at agr.unicamp.br

  4. CONVERGENCE TO PROCESS ORGANIZATION BY MODEL OF PROCESS MATURITY

    Directory of Open Access Journals (Sweden)

    Blaženka Piuković Babičković

    2015-06-01

    Full Text Available With modern business process orientation binds primarily, process of thinking and process organizational structure. Although the business processes are increasingly a matter of writing and speaking, it is a major problem among the business world, especially in countries in transition, where it has been found that there is a lack of understanding of the concept of business process management. The aim of this paper is to give a specific contribution to overcoming the identified problem, by pointing out the significance of the concept of business process management, as well as the representation of the model for review of process maturity and tools that are recommended for use in process management.

  5. Event-driven process execution model for process virtual machine

    Institute of Scientific and Technical Information of China (English)

    WU Dong-yao; WEI Jun; GAO Chu-shu; DOU Wen-shen

    2012-01-01

    Current orchestration and choreography process engines only serve with dedicate process languages. To solve these problems, an Even~driven Process Execution Model (EPEM) was developed. Formalization and map- ping principles of the model were presented to guarantee the correctness and efficiency for process transformation. As a case study, the EPEM descriptions of Web Services Business Process Execution Language (WS~BPEL) were represented and a Process Virtual Machine (PVM)-OncePVM was implemented in compliance with the EPEM.

  6. Analog modelling of obduction processes

    Science.gov (United States)

    Agard, P.; Zuo, X.; Funiciello, F.; Bellahsen, N.; Faccenna, C.; Savva, D.

    2012-04-01

    Obduction corresponds to one of plate tectonics oddities, whereby dense, oceanic rocks (ophiolites) are presumably 'thrust' on top of light, continental ones, as for the short-lived, almost synchronous Peri-Arabic obduction (which took place along thousands of km from Turkey to Oman in c. 5-10 Ma). Analog modelling experiments were performed to study the mechanisms of obduction initiation and test various triggering hypotheses (i.e., plate acceleration, slab hitting the 660 km discontinuity, ridge subduction; Agard et al., 2007). The experimental setup comprises (1) an upper mantle, modelled as a low-viscosity transparent Newtonian glucose syrup filling a rigid Plexiglas tank and (2) high-viscosity silicone plates (Rhodrosil Gomme with PDMS iron fillers to reproduce densities of continental or oceanic plates), located at the centre of the tank above the syrup to simulate the subducting and the overriding plates - and avoid friction on the sides of the tank. Convergence is simulated by pushing on a piston at one end of the model with velocities comparable to those of plate tectonics (i.e., in the range 1-10 cm/yr). The reference set-up includes, from one end to the other (~60 cm): (i) the piston, (ii) a continental margin containing a transition zone to the adjacent oceanic plate, (iii) a weakness zone with variable resistance and dip (W), (iv) an oceanic plate - with or without a spreading ridge, (v) a subduction zone (S) dipping away from the piston and (vi) an upper, active continental margin, below which the oceanic plate is being subducted at the start of the experiment (as is known to have been the case in Oman). Several configurations were tested and over thirty different parametric tests were performed. Special emphasis was placed on comparing different types of weakness zone (W) and the extent of mechanical coupling across them, particularly when plates were accelerated. Displacements, together with along-strike and across-strike internal deformation in all

  7. Business process modeling for processing classified documents using RFID technology

    Directory of Open Access Journals (Sweden)

    Koszela Jarosław

    2016-01-01

    Full Text Available The article outlines the application of the processing approach to the functional description of the designed IT system supporting the operations of the secret office, which processes classified documents. The article describes the application of the method of incremental modeling of business processes according to the BPMN model to the description of the processes currently implemented (“as is” in a manual manner and target processes (“to be”, using the RFID technology for the purpose of their automation. Additionally, the examples of applying the method of structural and dynamic analysis of the processes (process simulation to verify their correctness and efficiency were presented. The extension of the process analysis method is a possibility of applying the warehouse of processes and process mining methods.

  8. Process correlation analysis model for process improvement identification.

    Science.gov (United States)

    Choi, Su-jin; Kim, Dae-Kyoo; Park, Sooyong

    2014-01-01

    Software process improvement aims at improving the development process of software systems. It is initiated by process assessment identifying strengths and weaknesses and based on the findings, improvement plans are developed. In general, a process reference model (e.g., CMMI) is used throughout the process of software process improvement as the base. CMMI defines a set of process areas involved in software development and what to be carried out in process areas in terms of goals and practices. Process areas and their elements (goals and practices) are often correlated due to the iterative nature of software development process. However, in the current practice, correlations of process elements are often overlooked in the development of an improvement plan, which diminishes the efficiency of the plan. This is mainly attributed to significant efforts and the lack of required expertise. In this paper, we present a process correlation analysis model that helps identify correlations of process elements from the results of process assessment. This model is defined based on CMMI and empirical data of improvement practices. We evaluate the model using industrial data.

  9. a Study of Using Hydrogen Gas for Steam Boiler in CHOLOR- Alkali Manufacturing

    Science.gov (United States)

    Peantong, Sasitorn; Tangjitsitcharoen, Somkiat

    2017-06-01

    Main products of manufacturing of Cholor - Alkali, which commonly known as industrial chemical, are chlorine gas (Cl2), Sodium Hydroxide (NaOH) and hydrogen gas (H2). Chorine gas and sodium hydroxide are two main products for commercial profit; where hydrogen gas is by product. Most industries release hydrogen gas to atmosphere as it is non-profitable and less commercial scale. This study aims to make the most use of hydrogen as a substitute energy of natural gas for steam boiler to save energy cost. The second target of this study is to reduce level of CO2 release to air as a consequence of boiler combustion. This study suggests to install boiler that bases on hydrogen as main power with a high turndown ratio of at least 1:6. However, this case study uses boiler with two mode such as natural gas (NG) mode and mixed mode as they need to be flexible for production. Never the less, the best boiler selection is to use single mode energy of hydrogen. The most concerned issue about hydrogen gas is explosion during combustion stage. Stabilization measures at emergency stop is introduced to control H2 pressure to protect the explosion. This study varies ratio of natural gas to hydrogen gas to find the optimal level of two energy sources for boiler and measure total consumption through costing model; where CO2 level is measured at the boiler stack. The result of this study shows that hydrogen gas can be a substitute energy with natural gas and can reduce cost. Natural gas cost saving is 248,846 baht per month and reduce level of NOx is 80 ppm 7% O2 and 2 % of CO2 release to air as a consequence of boiler combustion.

  10. Specific Emissions of Harmful Substances from Small Boilers

    Directory of Open Access Journals (Sweden)

    Horák Jiøí

    1998-09-01

    Full Text Available Coal is on of the most important energy source and its significance will increase in a future. In Czech republic coal is except else widely used as a fuel for combustion in a small boilers (up to 50 kW. Low efficiency of the small boilers which is often below 50% together with high emissions of the harmful substances into near surroundings cause in average 40 – 70% of total local air pollution. The research was performed in a scope of the Grant no. 101/98/0820 of Grant Agency of Czech Republic was focused on quality of combustion process related to combustion efficiency and creation of harmful substances at combustion of domestic fuels. Experiments were performed to compare combustion of brown coal, clack coal, coke and black coal slurry. Extremely high creation of harmful substances (CO, NOX, solid particles and organic substances was measured when the black coal slurry was used as a fuel, measured in kg of emissions per GJ of burned fuel. Combustion of brown coal produced significant emissions of solid particles which bond harmful substances as metals, polyaromatic hydrocarbons and others together with high emissions of SO2 . Strong dependence between emissions of CO and low quality of combustion given by low combustion temperature, shortage of combustion air, not suitable design of after-combustion chamber and short duration of fuel presence in a combustion area was found out. Emissions of wide range of metals were investigated. The results of the research grant project describe and explain the combustion process and creation of harmful substances in small boilers plus give suggestions and recommendations leading to rational operation of the small boilers and lowering their negative impact to environment.

  11. Effect of Pellet Boiler Exhaust on Secondary Organic Aerosol Formation from α-Pinene.

    Science.gov (United States)

    Kari, Eetu; Hao, Liqing; Yli-Pirilä, Pasi; Leskinen, Ari; Kortelainen, Miika; Grigonyte, Julija; Worsnop, Douglas R; Jokiniemi, Jorma; Sippula, Olli; Faiola, Celia L; Virtanen, Annele

    2017-02-07

    Interactions between anthropogenic and biogenic emissions, and implications for aerosol production, have raised particular scientific interest. Despite active research in this area, real anthropogenic emission sources have not been exploited for anthropogenic-biogenic interaction studies until now. This work examines these interactions using α-pinene and pellet boiler emissions as a model test system. The impact of pellet boiler emissions on secondary organic aerosol (SOA) formation from α-pinene photo-oxidation was studied under atmospherically relevant conditions in an environmental chamber. The aim of this study was to identify which of the major pellet exhaust components (including high nitrogen oxide (NOx), primary particles, or a combination of the two) affected SOA formation from α-pinene. Results demonstrated that high NOx concentrations emitted by the pellet boiler reduced SOA yields from α-pinene, whereas the chemical properties of the primary particles emitted by the pellet boiler had no effect on observed SOA yields. The maximum SOA yield of α-pinene in the presence of pellet boiler exhaust (under high-NOx conditions) was 18.7% and in the absence of pellet boiler exhaust (under low-NOx conditions) was 34.1%. The reduced SOA yield under high-NOx conditions was caused by changes in gas-phase chemistry that led to the formation of organonitrate compounds.

  12. Optimization of a Centrifugal Boiler Circulating Pump's Casing Based on CFD and FEM Analyses

    Directory of Open Access Journals (Sweden)

    Zhigang Zuo

    2014-04-01

    Full Text Available It is important to evaluate the economic efficiency of boiler circulating pumps in manufacturing process from the manufacturers' point of view. The possibility of optimizing the pump casing with respect to structural pressure integrity and hydraulic performance was discussed. CFD analyses of pump models with different pump casing sizes were firstly carried out for the hydraulic performance evaluation. The effects of the working temperature and the sealing ring on the hydraulic efficiency were discussed. A model with casing diameter of 0.875D40 was selected for further analyses. FEM analyses were then carried out on different combinations of casing sizes, casing wall thickness, and materials, to evaluate its safety related to pressure integrity, with respect to both static and fatigue strength analyses. Two models with forging and cast materials were selected as final results.

  13. 硫磺制酸工艺中余热锅炉的爆炸影响模拟计算%Explosion Simulation of Waste Heat Boiler in Sulfuric Acid Process

    Institute of Scientific and Technical Information of China (English)

    曹伦

    2011-01-01

    Explosion of waste heat boiler was simulated,cause and risk were distinguished and safety precautions were proposed.%对余热回收装置中危险等级较高的锅炉爆炸及其造成的影响进行模拟计算,探讨形成爆炸的原因并提出安全对策措施。

  14. Boiler scale prevention employing an organic chelant

    Science.gov (United States)

    Wallace, Steven L.; Griffin, Jr., Freddie; Tvedt, Jr., Thorwald J.

    1984-01-01

    An improved method of treating boiler water which employs an oxygen scavenging compound and a compound to control pH together with a chelating agent, wherein the chelating agent is hydroxyethylethylenediaminetriacetic acid.

  15. 30 CFR 56.13030 - Boilers.

    Science.gov (United States)

    2010-07-01

    ... Valves BNon-ASME Code Boilers and Pressure Vessels CStorage of Mild Steel Covered Arc Welding Electrodes... American Society of Mechanical Engineers, 22 Law Drive, P.O. Box 2900, Fairfield, New Jersey 07007,...

  16. 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

  17. A new process sensitivity index to identify important system processes under process model and parametric uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Heng [Pacific Northwest National Laboratory, Richland Washington USA; Ye, Ming [Department of Scientific Computing, Florida State University, Tallahassee Florida USA; Walker, Anthony P. [Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge Tennessee USA; Chen, Xingyuan [Pacific Northwest National Laboratory, Richland Washington USA

    2017-04-01

    Hydrological models are always composed of multiple components that represent processes key to intended model applications. When a process can be simulated by multiple conceptual-mathematical models (process models), model uncertainty in representing the process arises. While global sensitivity analysis methods have been widely used for identifying important processes in hydrologic modeling, the existing methods consider only parametric uncertainty but ignore the model uncertainty for process representation. To address this problem, this study develops a new method to probe multimodel process sensitivity by integrating the model averaging methods into the framework of variance-based global sensitivity analysis, given that the model averaging methods quantify both parametric and model uncertainty. A new process sensitivity index is derived as a metric of relative process importance, and the index includes variance in model outputs caused by uncertainty in both process models and model parameters. For demonstration, the new index is used to evaluate the processes of recharge and geology in a synthetic study of groundwater reactive transport modeling. The recharge process is simulated by two models that converting precipitation to recharge, and the geology process is also simulated by two models of different parameterizations of hydraulic conductivity; each process model has its own random parameters. The new process sensitivity index is mathematically general, and can be applied to a wide range of problems in hydrology and beyond.

  18. 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.

  19. Removal of External Deposits on Boiler Tubes

    Directory of Open Access Journals (Sweden)

    C. P. De

    1970-07-01

    Full Text Available The superheater tubes in Port and Starboard boilers were found to have completely clogged by heavy deposits, which on analysis mainly vanadium pentoxide and sodium sulphmatter. The cleaning of the deposits was accomplished by alternate spraying with 15-20 per cent hydrogen peroxide and washing with hot water jets. Over the past two years, since the date of cleaning, the IN ship is operating without any trouble in the boilers.

  20. Properties of spatial Cox process models

    DEFF Research Database (Denmark)

    Møller, Jesper

    Probabilistic properties of Cox processes of relevance for statistical modelling and inference are studied. Particularly, we study the most important classes of Cox processes, including log Gaussian Cox processes, shot noise Cox processes, and permanent Cox processes. We consider moment propertie...

  1. Modeling process flow using diagrams

    NARCIS (Netherlands)

    Kemper, B.; de Mast, J.; Mandjes, M.

    2010-01-01

    In the practice of process improvement, tools such as the flowchart, the value-stream map (VSM), and a variety of ad hoc variants of such diagrams are commonly used. The purpose of this paper is to present a clear, precise, and consistent framework for the use of such flow diagrams in process

  2. Modeling process flow using diagrams

    NARCIS (Netherlands)

    Kemper, B.; de Mast, J.; Mandjes, M.

    2010-01-01

    In the practice of process improvement, tools such as the flowchart, the value-stream map (VSM), and a variety of ad hoc variants of such diagrams are commonly used. The purpose of this paper is to present a clear, precise, and consistent framework for the use of such flow diagrams in process improv

  3. A numerical study of pulverized coal ignition by means of plasma torches in air-coal dust mixture ducts of utility boiler furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Belosevic, S.; Sijercic, M.; Stefanovic, P. [Institute for Nuclear Science Vinca, Belgrade (Serbia)

    2008-04-15

    Paper presents selected results of numerical simulation of processes in air-coal dust mixture duct of pulverized coal utility boiler furnace with plasma-system for pulverized coal ignition and combustion stabilization. Application of the system in utility boiler furnaces promises to achieve important savings compared with the use of heavy oil burners. Plasma torches are built in air-coal dust mixture ducts between coal mills and burners. Calculations have been performed for one of rectangular air-coal dust mixture ducts with two opposite plasma torches, used in 210 MWe utility boiler firing pulverized Serbian lignite. The simulations are based on a three-dimensional mathematical model of mass, momentum and heat transfer in reacting turbulent gas-particle flow, specially developed for the purpose. Characteristics of processes in the duct are analyzed in the paper, with respect to the numerical results. The plasma-system thermal effect is discussed as well, regarding corresponding savings of liquid fuel. It has been emphasized that numerical simulation of the processes can be applied in optimization of pulverized coal ignition and combustion stabilization and enables efficient and cost-effective scaling-up procedure from laboratory to industrial scale.

  4. IHI-FW circulating fluidized bed boiler

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, S.; Omata, K.; Ishimoto, R.; Asai, M. (Ishikawajima-Harima Heavy Industries, Co. Ltd., Tokyo (Japan))

    1993-07-01

    The technology and application of the circulating fluidized bed boiler (IHI-FW) are outlined. Circulating fluidized bed boilers have various features as compared with bubbling fluidized bed boilers as follows; a high combustion efficiency, efficient use of limestone for desulfurization, low NOx emission, adaptability to various fuels and capability to cope with load change. The IHI-FW boiler is furthermore featured by water-wall furnace of all-welded structure, water-cooled/steam cooled cyclone, and simple circulating system. The 30 t/h circulating fluidized bed boiler was introduced into the Tsu Works, Omikenshi Co., Ltd., Japan for private power generation. The boiler equipped with a backup heavy oil burner mainly uses semi-anthracite coal, and besides sulfur capture and NOx reduction functions of a bed, a bag filter with a high dust collecting efficiency is installed in an exhaust gas system. The installation period was reduced to 2.5 months, a half of conventional ones, by more assembly in a factory followed by less field works. 7 figs., 2 tabs.

  5. Context Based Reasoning in Business Process Models

    OpenAIRE

    Balabko, Pavel; Wegmann, Alain

    2003-01-01

    Modeling approaches often are not adapted to human reasoning: models are ambiguous and imprecise. A same model element may have multiple meanings in different functional roles of a system. Existing modeling approaches do not relate explicitly these functional roles with model elements. A principle that can solve this problem is that model elements should be defined in a context. We believe that the explicit modeling of context is especially useful in Business Process Modeling (BPM) where the ...

  6. Sulphur recirculation for reduced boiler corrosion; Minskad pannkorrosion med svavelrecirkulation

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Sven; Karlsson, Martin (Goetaverken Miljoe AB, Goeteborg (Sweden)); Blomqvist, Evalena; Baefver, Linda; Claesson, Frida; Davidsson, Kent (SP Sveriges Tekniska Forskningsinstitut, Boraas (Sweden)); Froitzheim, Jan; Pettersson, Jesper; Steenari, Britt-Marie (Chalmers Tekniska Hoegskola, Oorganisk miljoekemi, Goeteborg (Sweden))

    2010-03-15

    Sulphur recirculation is a new technology for reducing boiler corrosion and dioxin formation, which was demonstrated in full-scale tests performed at the Renova Waste to Energy plant at Saevenaes in Goeteborg (Sweden). Sulphur is recirculated from the flue gas cleaning back to the boiler, which reduces the chloride content of the deposits, which in turn reduces boiler corrosion and dioxin formation. Sulphur dioxide was separated from the flue gas in a wet scrubber by adding hydrogen peroxide, producing sulphuric acid. The sulphuric acid was injected into the furnace using nozzles with atomization air, surrounded by recirculated flue gas for improved mixing. By recirculating the sulphur, the sulphur dioxide concentration was increased in the boiler. Each sulphur atom passed the boiler several times and no external sulphur had to be added. Dioxin, ash, deposits and particle samplings together with 1000 h corrosion probe measurements were performed for normal operation (reference) and with sulphur recirculation respectively. During spring 2009, reference measurements were made and the recirculation system was installed and tested. During autumn 2009, a long term test with sulphur recirculation was made. An SO{sub 2} concentration of approximately 800 mg/m3 (n, d.g.) was maintained in the boiler by the system except during a period of extremely low sulphur content in the waste. The sulphur dioxide stack concentrations have been far below the emission limit. Sulphuric acid dew point measurements have shown that the sulphuric acid dosage did not lead to elevated SO{sub 3} concentrations, which may otherwise lead to low temperature corrosion. The chlorine content of both fly ash and boiler ash decreased and the sulphur content increased during the sulphur recirculation tests. The molar chlorine/sulphur ratio (Cl/S) decreased by two thirds in the fly ash as well as in the boiler ash, except for one sample. With sulphur recirculation in operation, the deposit growth was

  7. High-Temperature Behavior of a NiCr-Coated T91 Boiler Steel in the Platen Superheater of Coal-Fired Boiler

    Science.gov (United States)

    Chatha, Sukhpal Singh; Sidhu, Hazoor S.; Sidhu, Buta S.

    2013-06-01

    Ni-20Cr coating was deposited on T91 boiler tube steel by high-velocity oxy-fuel (HVOF) process to enhance high-temperature oxidation resistance. High-temperature performance of bare, as well as HVOF-coated steel specimens was evaluated for 1500 h under in the platen superheater zone of coal-fired boiler, where the temperature was around 900 °C. Experiments were carried out for 15 cycles, each of 100-h duration followed by 1-h cooling at ambient temperature. The extent of degradation of the specimens was assessed by the thickness loss and depth of internal corrosion attack. Ni-20Cr-coated steel performed better than the uncoated steel in actual boiler environment. The improved degradation resistance of Ni-20Cr coating can be attributed to the presence of Cr2O3 in the top oxide scale and dense microstructure.

  8. Modelling of Batch Process Operations

    DEFF Research Database (Denmark)

    2011-01-01

    Here a batch cooling crystalliser is modelled and simulated as is a batch distillation system. In the batch crystalliser four operational modes of the crystalliser are considered, namely: initial cooling, nucleation, crystal growth and product removal. A model generation procedure is shown that s...

  9. Birth/death process model

    Science.gov (United States)

    Solloway, C. B.; Wakeland, W.

    1976-01-01

    First-order Markov model developed on digital computer for population with specific characteristics. System is user interactive, self-documenting, and does not require user to have complete understanding of underlying model details. Contains thorough error-checking algorithms on input and default capabilities.

  10. Steady-State Process Modelling

    DEFF Research Database (Denmark)

    2011-01-01

    This chapter covers the basic principles of steady state modelling and simulation using a number of case studies. Two principal approaches are illustrated that develop the unit operation models from first principles as well as through application of standard flowsheet simulators. The approaches i...

  11. Modeling business processes: theoretical and practical aspects

    Directory of Open Access Journals (Sweden)

    V.V. Dubininа

    2015-06-01

    Full Text Available The essence of process-oriented enterprise management has been examined in the article. The content and types of information technology have been analyzed in the article, due to the complexity and differentiation of existing methods, as well as the specificity of language, terminology of the enterprise business processes modeling. The theoretical aspects of business processes modeling have been reviewed and the modern traditional modeling techniques received practical application in the visualization model of retailers activity have been studied in the article. In the process of theoretical analysis of the modeling methods found that UFO-toolkit method that has been developed by Ukrainian scientists due to it systemology integrated opportunities, is the most suitable for structural and object analysis of retailers business processes. It was designed visualized simulation model of the business process "sales" as is" of retailers using a combination UFO-elements with the aim of the further practical formalization and optimization of a given business process.

  12. A Comparative of business process modelling techniques

    Science.gov (United States)

    Tangkawarow, I. R. H. T.; Waworuntu, J.

    2016-04-01

    In this era, there is a lot of business process modeling techniques. This article is the research about differences of business process modeling techniques. For each technique will explain about the definition and the structure. This paper presents a comparative analysis of some popular business process modelling techniques. The comparative framework is based on 2 criteria: notation and how it works when implemented in Somerleyton Animal Park. Each technique will end with the advantages and disadvantages. The final conclusion will give recommend of business process modeling techniques that easy to use and serve the basis for evaluating further modelling techniques.

  13. Modeling Events with Cascades of Poisson Processes

    CERN Document Server

    Simma, Aleksandr

    2012-01-01

    We present a probabilistic model of events in continuous time in which each event triggers a Poisson process of successor events. The ensemble of observed events is thereby modeled as a superposition of Poisson processes. Efficient inference is feasible under this model with an EM algorithm. Moreover, the EM algorithm can be implemented as a distributed algorithm, permitting the model to be applied to very large datasets. We apply these techniques to the modeling of Twitter messages and the revision history of Wikipedia.

  14. The Computer-Aided Analytic Process Model. Operations Handbook for the Analytic Process Model Demonstration Package

    Science.gov (United States)

    1986-01-01

    Research Note 86-06 THE COMPUTER-AIDED ANALYTIC PROCESS MODEL : OPERATIONS HANDBOOK FOR THE ANALYTIC PROCESS MODEL DE ONSTRATION PACKAGE Ronald G...ic Process Model ; Operations Handbook; Tutorial; Apple; Systems Taxonomy Mod--l; Training System; Bradl1ey infantry Fighting * Vehicle; BIFV...8217. . . . . . . .. . . . . . . . . . . . . . . . * - ~ . - - * m- .. . . . . . . item 20. Abstract -continued companion volume-- "The Analytic Process Model for

  15. Estimation of capability of changing the boilers TP-14A at Kumertau Termal Power Station to burning B3 grade coal from Verkhne-Sokursky deposit

    Science.gov (United States)

    Supranov, V. M.; Shtegman, A. V.; Fomenko, E. A.

    2016-04-01

    Currently, TP-14A boilers should be changed into burning off-design fuel: grade B3 coal of Verkhne-Sokursky deposit. Its share (by heat) in the fuel balance should be not less than 80%. A test burning of Verkhne-Sokursky coal was carried out, which showed that, in its present form, the boilers and dust-systems are not suitable to operate with this fuel, because their characteristics significantly differs from the project one. It is impossible to maintain the overheating temperature at the required level during operation on only coal; it is difficult to maintain the temperature behind the mills at the level of 200°C. The joint burning the coal with natural gas allows to solve these problems at operation of one or two mills. However, substantial fuel underburning, essential thermal maldistributions on the steam flows, and emissions of NO x above permissible values is observed. Based on the results of test burning and joint calculations of furnace, boiler, and dust-systems, ways to solve these problems were developed. For modeling the furnace process, the Fluent and Sigma Flame software were used. Adapted mathematical models of the boiler and dust-preparing systems were created using the Boiler Designer and Stoker software. It is necessary to reconstruct the boiler plants, which can perform in two stages. In the first stage, the existing burners are replaced by the burners with turning nozzles and two-stage burning is arranged, and the inertial separators and recirculation of the drying agent are installed on the mills. In the second stage, the change to concentric burning is carried out, the heating surface of radiation part of the steam superheater increases, and the preset included hammer part is installed at the mill. It is shown that a positive effect should be obtained already after the first stage of reconstruction. The second stage of reconstruction will require additional expenses, but its implementation will allow to a greater extent to eliminate the

  16. Systematic approach for the identification of process reference models

    CSIR Research Space (South Africa)

    Van Der Merwe, A

    2009-02-01

    Full Text Available Process models are used in different application domains to capture knowledge on the process flow. Process reference models (PRM) are used to capture reusable process models, which should simplify the identification process of process models...

  17. Optimized CO2-flue gas separation model for a coal fired power plant

    Directory of Open Access Journals (Sweden)

    Udara S. P. R. Arachchige, Muhammad Mohsin, Morten C. Melaaen

    2013-01-01

    Full Text Available The detailed description of the CO2 removal process using mono-ethylamine (MEA as a solvent for coal-fired power plant is present in this paper. The rate based Electrolyte NRTL activity coefficient model was used in the Aspen Plus. The complete removal process with re-circulating solvent back to the absorber was implemented with the sequential modular method in Aspen Plus. The most significant cost related to CO2 capture is the energy requirement for re-generating solvent, i.e. re-boiler duty. Parameters’ effects on re-boiler duty were studied, resulting decreased re-boiler duty with the packing height and absorber packing diameter, absorber pressure, solvent temperature, stripper packing height and diameter. On the other hand, with the flue gas temperature, re-boiler duty is increased. The temperature profiles and CO2 loading profiles were used to check the model behavior.

  18. Optimized CO2-flue gas separation model for a coal fired power plant

    Energy Technology Data Exchange (ETDEWEB)

    Arachchige, Udara S.P.R. [Telemark University College, Porsgrunn (Norway); Mohsin, Muhammad [Telemark University College, Porsgrunn (Norway); Melaaen, Morten C. [Telemark University College, Porsgrunn (Norway); Tel-Tek, Porsgrunn (Norway)

    2013-07-01

    The detailed description of the CO2 removal process using mono-ethylamine (MEA) as a solvent for coal-fired power plant is present in this paper. The rate based Electrolyte NRTL activity coefficient model was used in the Aspen Plus. The complete removal process with re-circulating solvent back to the absorber was implemented with the sequential modular method in Aspen Plus. The most significant cost related to CO2 capture is the energy requirement for re-generating solvent, i.e. re-boiler duty. Parameters’ effects on re-boiler duty were studied, resulting decreased re-boiler duty with the packing height and absorber packing diameter, absorber pressure, solvent temperature, stripper packing height and diameter. On the other hand, with the flue gas temperature, re-boiler duty is increased. The temperature profiles and CO2 loading profiles were used to check the model behavior.

  19. Ada COCOMO and the Ada Process Model

    Science.gov (United States)

    1989-01-01

    language, the use of incremental development, and the use of the Ada process model capitalizing on the strengths of Ada to improve the efficiency of software...development. This paper presents the portions of the revised Ada COCOMO dealing with the effects of Ada and the Ada process model . The remainder of...this section of the paper discusses the objectives of Ada COCOMO. Section 2 describes the Ada Process Model and its overall effects on software

  20. Simulation Modeling of Software Development Processes

    Science.gov (United States)

    Calavaro, G. F.; Basili, V. R.; Iazeolla, G.

    1996-01-01

    A simulation modeling approach is proposed for the prediction of software process productivity indices, such as cost and time-to-market, and the sensitivity analysis of such indices to changes in the organization parameters and user requirements. The approach uses a timed Petri Net and Object Oriented top-down model specification. Results demonstrate the model representativeness, and its usefulness in verifying process conformance to expectations, and in performing continuous process improvement and optimization.

  1. Corrosion of oil-fired domestic boilers

    Energy Technology Data Exchange (ETDEWEB)

    Koebel, M.; Elsener, M.

    1989-05-01

    Depending on the surface temperature of the flue gas side the corrosion of oil fired domestic boilers proceeds either mainly by acid corrosion or by oxygen corrosion: (1) At surface temperatures of 60/sup 0/C and higher the corrosion mechanism of acid corrosion prevails and the corrosion rates amount to 0.1-0.3 mm/year (values referred to continuous burner operation). The corrosion products consist of soluble iron(II)- and iron(III)sulfates. Higher corrosion rates can be attributed to an appreciable catalytic formation of sulfur trioxide on the corrosion products formed on the convective heating surfaces. (2) At surface temperatures of 40/sup 0/C the mechanism of oxygen corrosion already dominates and the corrosion rates are about ten times higher (1.5-3 mm/year, referred to continuous burner operation). The high portion of iron oxide hydrates, especially goethit (/alpha/-FeOOH), makes the corrosion products difficult to remove. (3) Distinctly reduced service lives are also expected for the so called reduced temperature boilers ('Niedertemperaturkessel') and low temperature boilers ('Tieftemperaturkessel'): According to the manufacturers these boilers may be operated at boiler water temperatures well below 60/sup 0/C, as they are equipped with constructive measures to enhance the surface temperature on the flue gas side. However, these measures are only fully effective under stationary conditions. Some of the results were obtained from weight loss measurements on test specimen made from St 35.8 and gray cast iron, that were exposed to the flue gases of an fired experimental boiler. Other important results come from field measurements of the sulfuric acid content of about 30 boilers that are in practical use. (orig.).

  2. Branching process models of cancer

    CERN Document Server

    Durrett, Richard

    2015-01-01

    This volume develops results on continuous time branching processes and applies them to study rate of tumor growth, extending classic work on the Luria-Delbruck distribution. As a consequence, the authors calculate the probability that mutations that confer resistance to treatment are present at detection and quantify the extent of tumor heterogeneity. As applications, the authors evaluate ovarian cancer screening strategies and give rigorous proofs for results of Heano and Michor concerning tumor metastasis. These notes should be accessible to students who are familiar with Poisson processes and continuous time. Richard Durrett is mathematics professor at Duke University, USA. He is the author of 8 books, over 200 journal articles, and has supervised more than 40 Ph.D. students. Most of his current research concerns the applications of probability to biology: ecology, genetics, and most recently cancer.

  3. A Process Model for Establishing Business Process Crowdsourcing

    OpenAIRE

    Nguyen Hoang Thuan; Pedro Antunes; David Johnstone

    2017-01-01

    Crowdsourcing can be an organisational strategy to distribute work to Internet users and harness innovation, information, capacities, and variety of business endeavours. As crowdsourcing is different from other business strategies, organisations are often unsure as to how to best structure different crowdsourcing activities and integrate them with other organisational business processes. To manage this problem, we design a process model guiding how to establish business process crowdsourcing....

  4. Total Ship Design Process Modeling

    Science.gov (United States)

    2012-04-30

    Microsoft Project® or Primavera ®, and perform process simulations that can investigate risk, cost, and schedule trade-offs. Prior efforts to capture...planning in the face of disruption, delay, and late‐changing  requirements. ADePT is interfaced with  PrimaVera , the AEC  industry favorite program

  5. Fuel sulfur and boiler fouling

    Energy Technology Data Exchange (ETDEWEB)

    Litzke, W.; Celebi, Y.; Butcher, T. [Brookhaven National Lab., Upton, NY (United States)

    1995-04-01

    Fouling of the heat transfer surfaces of boilers and furnaces by `soot` leads to reduced efficiency and increased service requirements. The average level of annual efficiency reduction as a result of fouling if generally accepted as 2% per year. Improving the efficiency of equipment in the field may be the most important oil heat conservation opportunity at present. Improvements can be realized by reducing fouling rates, promoting lower firing rates in existing equipment, and enabling excess air levels to be set lower without raising concerns about increased service requirements. In spite of the importance of efficiency in the field there is very little data available on efficiency degradation rates with modern equipment, actual field operating conditions (excess air and smoke number settings) and service problems which affect efficiency. During 1993-94 field tests were initiated to obtain such data and to obtain information that would compliment existing and current laboratory work. Experimental work conducted on a bench scale level have included tests with various advanced burners, fuel types, and different operating conditions which have been done at the BNL Rapid Fouling Test Facility. This report will focus on the field study of fouling effects on ten residential heating service problems at each site are summarized. In addition, the technical difficulties involved with conducting such a field study shall also be discussed as the findings should serve to improve future work in this area.

  6. Robust H(infinity) tracking control of boiler-turbine systems.

    Science.gov (United States)

    Wu, J; Nguang, S K; Shen, J; Liu, G; Li, Y G

    2010-07-01

    In this paper, the problem of designing a fuzzy H(infinity) state feedback tracking control of a boiler-turbine is solved. First, the Takagi and Sugeno fuzzy model is used to model a boiler-turbine system. Next, based on the Takagi and Sugeno fuzzy model, sufficient conditions for the existence of a fuzzy H(infinity) nonlinear state feedback tracking control are derived in terms of linear matrix inequalities. The advantage of the proposed tracking control design is that it does not involve feedback linearization technique and complicated adaptive scheme. An industrial boiler-turbine system is used to illustrate the effectiveness of the proposed design as compared with a linearized approach.

  7. Modeling and simulation of membrane process

    Science.gov (United States)

    Staszak, Maciej

    2017-06-01

    The article presents the different approaches to polymer membrane mathematical modeling. Traditional models based on experimental physicochemical correlations and balance models are presented in the first part. Quantum and molecular mechanics models are presented as they are more popular for polymer membranes in fuel cells. The initial part is enclosed by neural network models which found their use for different types of processes in polymer membranes. The second part is devoted to models of fluid dynamics. The computational fluid dynamics technique can be divided into solving of Navier-Stokes equations and into Boltzmann lattice models. Both approaches are presented focusing on membrane processes.

  8. GPstuff: Bayesian Modeling with Gaussian Processes

    NARCIS (Netherlands)

    Vanhatalo, J.; Riihimaki, J.; Hartikainen, J.; Jylänki, P.P.; Tolvanen, V.; Vehtari, A.

    2013-01-01

    The GPstuff toolbox is a versatile collection of Gaussian process models and computational tools required for Bayesian inference. The tools include, among others, various inference methods, sparse approximations and model assessment methods.

  9. Online Rule Generation Software Process Model

    National Research Council Canada - National Science Library

    Sudeep Marwaha; Alka Aroa; Satma M C; Rajni Jain; R C Goyal

    2013-01-01

    .... The software process model for rule generation using decision tree classifier refers to the various steps required to be executed for the development of a web based software model for decision rule generation...

  10. Modeling pellet impact drilling process

    OpenAIRE

    Kovalev, Artem Vladimirovich; Ryabchikov, Sergey Yakovlevich; Isaev, Evgeniy Dmitrievich; Ulyanova, Oksana Sergeevna

    2016-01-01

    The paper describes pellet impact drilling which could be used to increase the drilling speed and the rate of penetration when drilling hard rocks. Pellet impact drilling implies rock destruction by metal pellets with high kinetic energy in the immediate vicinity of the earth formation encountered. The pellets are circulated in the bottom hole by a high velocity fluid jet, which is the principle component of the ejector pellet impact drill bit. The experiments conducted has allowed modeling t...

  11. Optimization of Boiler Control to Improve the Load-following Capability of Power-plant Units

    DEFF Research Database (Denmark)

    Mortensen, J. H.; Mølbak, T.; Andersen, Palle;

    1998-01-01

    therefore been developed. The system is implemented as a complement, producing control signals to be added to those of the existing boiler control system, a concept which has various practical advantages in terms of implementation and commissioning. The optimizing control system takes account...... of the multivariable and load-de*pendent nonlinear characteristics of the boiler process, as a scheduled LQG controller with feedforward action is utilized. The LQG controller improves the control of critical pro*cess variables, making it possible to increase the load-following capability of a specific plant. Field...

  12. Optimization of Boiler Control to Improve the Load-following Capability of Power-plant Units

    DEFF Research Database (Denmark)

    Mortensen, J. H.; Mølbak, T.; Andersen, Palle;

    therefore been developed. The system is implemented as a complement, producing control signals to be added to those of the existing boiler control system, a concept which has various practical advantages in terms of implementation and commissioning. The optimizing control system takes account...... of the multivariable and load-de*pendent nonlinear characteristics of the boiler process, as a scheduled LQG controller with feedforward action is utilized. The LQG controller improves the control of critical pro*cess variables, making it possible to increase the load-following capability of a specific plant. Field...

  13. Interpretive and Formal Models of Discourse Processing.

    Science.gov (United States)

    Bulcock, Jeffrey W.; Beebe, Mona J.

    Distinguishing between interpretive and formal models of discourse processing and between qualitative and quantitative research, this paper argues that formal models are the analogues of interpretive models, and that the two are complementary. It observes that interpretive models of reading are being increasingly derived from qualitative research…

  14. Orion Boiler Plate Airdrop Test System

    Science.gov (United States)

    Machin, Ricardo A.; Evans, Carol T.

    2013-01-01

    On the 29th of February 2012 the Orion Capsule Parachute Assembly System (CPAS) project attempted to perform an airdrop test of a boilerplate test article for the second time. The first attempt (Cluster Development Test 2, July 2008) to deliver a similar boilerplate from a C-17 using the Low Velocity Air Drop (LVAD) technique resulted in the programmer parachute failing to properly inflate, the test article failing to achieve the desired test initiation conditions, and the test article a total loss. This paper will pick up where the CDT-2 failure investigation left off, describing the test technique that was adopted, and outline the modeling that was performed to gain confidence that the second attempt would be successful. The second boiler plate test (Cluster Development Test 3-3) was indeed a complete success and has subsequently been repeated several times, allowing the CPAS project to proceed with the full scale system level development testing required to integrate the hardware to the first Entry Flight Test vehicle as well as go into the Critical Design Review with minimum risk and a mature design.

  15. Optimization of Boiler Blowdown and Blowdown Heat Recovery in Textile Sector

    Directory of Open Access Journals (Sweden)

    Sunudas T

    2013-09-01

    Full Text Available Boilers are widely used in most of the processing industries like textile, for the heating applications. Surat is the one of the largest textile processing area in India. In textile industries coal is mainly used for the steam generation. In a textile industry normally a 4% of heat energy is wasted through blowdown. In the study conducted in steam boilers in textile industries in surat location, 1.5% of coal of total coal consumption is wasted in an industry by improper blowdwon. This thesis work aims to prevent the wastage in the coal use by optimizing the blowdown in the boiler and maximizing the recovery of heat wasting through blowdown.

  16. PARAMETERS OF AIR FIRED BOILER FED WITH DIFFERENT TYPES OF FUEL

    Directory of Open Access Journals (Sweden)

    Katarzyna Joanna Gładyszewska-Fiedoruk

    2016-09-01

    Full Text Available The measurement and interpretation of indoor carbon dioxide CO2 concentration can provide information on building indoor air quality and ventilation. On the other hand, concentration of carbon monoxide CO can show as how combustion process run and if the boiler is safe. When there is not sufficient air available to complete the combustion process, some of the fuel is left unburned, resulting in inefficiency and undesirable emissions. An examination of the CO2 and CO concentration in boiler and interpretation results help to improve indoor air quality. The paper presents characteristics of concentration CO2 and CO depend on used fuel in tested boiler rooms. The concentration curves show how each fuel combustion affect the amount of CO2 and CO that is produced.

  17. U.S. Experiences in Tackling Energy and Environmental Challenges of Boiler System

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Bo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Hongyou [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Lynn K. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-08-15

    In the U.S., energy consumption by steam and process heat combined accounts for over 50% of the total energy use from industrial systems (see Figure 1). The use of boilers, process heaters, and furnaces for generating steam and heat in industrial facilities, commercial settings, and institutions consumes significant amounts of energy and is one of major sources of hazardous air pollutants, which contribute significantly to local pollution and global climate change. To address the energy and environmental challenges caused by boiler systems in the U.S., the country has taken a series of actions to reduce emissions from industrial, commercial and institutional boilers, improve the efficiency of steam systems, replace coal with cleaner energy resources, and promote the wider use of combined heat and power (CHP).

  18. Boiler model of a 300 Mw fossil fuel power plant for the turbine turning simulator; Modelo de caldera de una planta termoelectrica de 300 Mw para el simulador de rodado de turbina

    Energy Technology Data Exchange (ETDEWEB)

    Rossano Roman, Miguel [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1993-07-01

    The objective of the model is to reproduce the behavior of a boiler of a 300 Mw fossil fuel unit, in the training turbine turning simulator. This simulator was designed to be used in the training that is performed in the control rooms or training centers of the fossil fuel power plants of the Comision Federal de Electricidad (CFE). In this article the equations of the model for a 300 Mw thermal plant are described, based in balances and physical relationships. The basic considerations and simplifications are shown. The model considers the combustion in the furnace, the dome, the downcomers, the recirculation pumps, the water walls, the superheater and the reheater. The mass and energy balances take into account the sensible heat of all the constituents involved, as well as the combustion heat. Heat transference zones by convection or by a combined mechanism convective-radiant, in the boiler furnace, are considered. The dome pressure is modeled with basis in the mass and energy balance, considering all the existing sources and sinks. The simulation also reflects the pressure transients due to thermal variations, combustion variations, and steam demand variations. The heat transference by convection is considered for all the tube banks along the combustion gases path to the stack. Comparisons were made with the design and operation data of the power station, using a selection of transient states to demonstrate de model fidelity. This selection was focussed of transients states, at the unit start up, since in this operation stage the turning and the heating of the turbine is accomplished. [Espanol] El objetivo del modelo es reproducir el comportamiento de una caldera de una unidad termoelectrica de 300 Mw, en el simulador para entrenamiento en rodado de turbina. Este simulador se diseno para ser utilizado en el entrenamiento que se realiza en los cuartos de control o centros de entrenamiento de las plantas termoelectricas de la Comision Federal de Electricidad (CFE

  19. Study of parametric methods for identification of mathematical models and Sundaresam method application in a steam boiler; Estudo dos metodos parametricos de identificacao de modelos matematicos e aplicacao do metodo de Sundaresam em uma caldeira a vapor

    Energy Technology Data Exchange (ETDEWEB)

    Schuttenberg, Rose Mary Cosso [Pontificia Univ. Catolica de Minas Gerais, Belo Horizonte, MG (Brazil). Nucleo de Controle de Processos

    1999-12-01

    Some identification techniques are discussed and the required data for application to the Sundaresam's identification method are obtained by connecting a microcomputer to the Spiraflo, an instrument available at the CEFET/MG - Federal Center for Technological Education of Minas Gerais, Brazil - steam boiler. All the graphical output, by an specified test, for the temperature, steam's flow and pressure are shown and analyzed. Through picked up data and Sundaresan's method, the transfer function between the pressure of the CEFET-MG's steam boiler and the flow is identified. (author)

  20. Large utility boilers: experience and design trends

    Energy Technology Data Exchange (ETDEWEB)

    Davis, C.M.; Haller, K.H.; Wiener, M.

    1976-01-01

    The 1960s were characterized by heavy emphasis on the supercritical cycle and a rapid escalation of utility boiler size. Since the units now in operation were designed, several important changes have caused drastic turns in boiler development. The 2400-lb/in./sup 2/ single-reheat, 1000/sup 0/F/1000/sup 0/F cycle regained importance. The present trend is toward natural circulation because it is the simplest, the most efficient, and the most reliable method of furnace wall cooling. With the emphasis on energy self-sufficiency, coal became the dominant boiler fuel. A great deal of uncertainty exists regarding future development of load growth, fossil to nuclear split, environmental regulations, availability of fuel and availability of capital for new construction. These factors are shaping the trends that we see: the utilization of all available coal sources, including very-low-grade coals, the design of units for a wide range of coals, the design for greater operating flexibility, and placement of heavy emphasis on reliability. Based on the good experience with recent large B and W coal-fired boilers, the even greater conservatism applied to new large, coal-fired boilers should provide the capability for continued good performance and high availability.

  1. Process modelling on a canonical basis[Process modelling; Canonical modelling

    Energy Technology Data Exchange (ETDEWEB)

    Siepmann, Volker

    2006-12-20

    Based on an equation oriented solving strategy, this thesis investigates a new approach to process modelling. Homogeneous thermodynamic state functions represent consistent mathematical models of thermodynamic properties. Such state functions of solely extensive canonical state variables are the basis of this work, as they are natural objective functions in optimisation nodes to calculate thermodynamic equilibrium regarding phase-interaction and chemical reactions. Analytical state function derivatives are utilised within the solution process as well as interpreted as physical properties. By this approach, only a limited range of imaginable process constraints are considered, namely linear balance equations of state variables. A second-order update of source contributions to these balance equations is obtained by an additional constitutive equation system. These equations are general dependent on state variables and first-order sensitivities, and cover therefore practically all potential process constraints. Symbolic computation technology efficiently provides sparsity and derivative information of active equations to avoid performance problems regarding robustness and computational effort. A benefit of detaching the constitutive equation system is that the structure of the main equation system remains unaffected by these constraints, and a priori information allows to implement an efficient solving strategy and a concise error diagnosis. A tailor-made linear algebra library handles the sparse recursive block structures efficiently. The optimisation principle for single modules of thermodynamic equilibrium is extended to host entire process models. State variables of different modules interact through balance equations, representing material flows from one module to the other. To account for reusability and encapsulation of process module details, modular process modelling is supported by a recursive module structure. The second-order solving algorithm makes it

  2. Factors controlling alkali salt deposition in recovery boilers - particle formation and deposition; Soodakattilan likaantuminen ja siihen vaikuttavien tekijoeiden hallinta - hiukkasten muodostuminen ja depositio

    Energy Technology Data Exchange (ETDEWEB)

    Kauppinen, E.I.; Mikkanen, P.; Ylaetalo, S. [VTT Chemistry, Espoo (Finland); Jokiniemi, J.K.; Lyyraenen, J.; Pyykoenen, J.; Saastamoinen, J. [VTT Energy, Espoo (Finland)

    1996-12-01

    In this project, the aim was to find out those critical factors that control the deposit formation in the recovery boilers. We focus on the particle formation, growth and deposition as well as the single black liquor particle combustion behaviour. The final goal is the development of the predictive model to be used to describe deposit growth and subsequent behaviour as well as the dependence of deposition on black liquor characteristics and boiler operation conditions. During year 1995 an experimental study on the aerosol particle formation within the recovery boiler furnace and a sensitivity study with the Aerosol Behaviour in Combustion (ABC) code were carried out. The experimental study confirmed the fact that the particles are already formed in the recovery boiler furnace. The particle formation is initiated in the boundary layer of the burning droplet or smelt bed, where metals are vaporised and oxidised to form tiny seed particles. Trace amounts of metals were measured in all particle sizes and the sensitivity study with the ABC model gave further evidence of the seed formation was necessary primary step in the particle formation. At the furnace outlet the sintration ratio and the sulfation ratio of the particles were dependent on the furnace temperature and the residence time in the furnace. At ESP inlet three types of particles were observed (1) fine particles with the major mass mode at about 1-2 {mu}m, (2) large agglomerates in sizes larger than 8 {mu}m, and (3) spherical particles about 2-4 {mu}m in size. The fine particles were formed from vapours and the large agglomerates were formed from fine particles agglomerated on heat exchanger surfaces and re-entrained back to flue gas flow. The large agglomerates also contain vapours that have directly condensed to surfaces. The large spherical particles contain silicon and pass the process almost unchanged. (Abstract Truncated)

  3. Safety conditions of steam boilers in companies associated with a professional risk administration company in Antioquia, 2009

    OpenAIRE

    Diego L. Sepúlveda M; Jairo Ramírez G

    2011-01-01

    Objective: to determine the safety conditions of steam boilers in companies associated with a professional risk administra-tion company in Antioquia, Colombia. To this end, their op-eration conditions shall be characterized, the associated risks identified, and their safety level assessed. Methodology:. a descriptive crosssectional study was carried out in twenty companies whose production processes involve boilers. A survey on the conditions for operation was applied on both the maintena...

  4. Research on Power Plant Steam Boiler Automatic Control System Based on Fuzzy Control%基于模糊控制的电厂蒸汽锅炉自动控制系统研究

    Institute of Scientific and Technical Information of China (English)

    周继春

    2013-01-01

      针对电厂发电过程中需对蒸汽锅炉进行自动控制的目的,提出了采用模糊控制原理实现蒸汽锅炉压力和温度的自动控制方案。通过深入研究火力发电厂中的蒸汽锅炉的工作循环过程,建立了蒸汽锅炉内部压力和温度的工作模型。文章详细设计了电厂蒸汽锅炉自动控制系统的总体方案,重点研究了模糊控制模块的设计原理和实现方法,给出了模糊控制中的隶属函数和各个主要变量的模糊化过程。最后通过仿真测试,分析了锅炉自动控制系统的工作性能。%Aiming at the automatic control aim in power plant generating electricity, this paper put forward a automatic control scheme steam boiler pressure and temperature, on fuzzy control principle. By further studying the steam boiler circulation process in thermal power plant, it built a steam boiler inner pressure and temperature working model. It design the power plant steam boiler automatic control system overall scheme in detail, focused on the design principle and implementation method, presented the membership function and main variables in the fuzzy process. At last, by simulation test, it analyzed the steam boiler control system working performance.

  5. An Extension to the Weibull Process Model

    Science.gov (United States)

    1981-11-01

    Subt5l . TYPE OF REPORT & PERIOD COVERED AN EXTENSION+TO THE WEIBULL PROCESS MODEL 6. PERFORMING O’G. REPORT NUMBER I. AuTHOR() S. CONTRACT OR GRANT...indicatinq its imrportance to applications. 4 AN EXTENSION TO TE WEIBULL PROCESS MODEL 1. INTRODUCTION Recent papers by Bain and Engelhardt (1980)1 and Crow

  6. Independent Research and Design of 600-MW Supercritical CFB Boiler

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In order to further develop and improve the technologies for large-capacity supercritical CFB boiler, the key technologies for large CFB boiler were systematically studied, based on the development of first domestically-made 210-MW and 330-MW CFB boilers. The scheme of 600-MW supercritical CFB boiler was designed, including the furnace structure, key components, steam-water system and auxiliary systems, which laid a technical foundation for the engineering applications.

  7. 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 ...

  8. Hybrid modelling of anaerobic wastewater treatment processes.

    Science.gov (United States)

    Karama, A; Bernard, O; Genovesi, A; Dochain, D; Benhammou, A; Steyer, J P

    2001-01-01

    This paper presents a hybrid approach for the modelling of an anaerobic digestion process. The hybrid model combines a feed-forward network, describing the bacterial kinetics, and the a priori knowledge based on the mass balances of the process components. We have considered an architecture which incorporates the neural network as a static model of unmeasured process parameters (kinetic growth rate) and an integrator for the dynamic representation of the process using a set of dynamic differential equations. The paper contains a description of the neural network component training procedure. The performance of this approach is illustrated with experimental data.

  9. Development of advanced monitoring methods to improve boiler availability and performance

    Energy Technology Data Exchange (ETDEWEB)

    Leino, T.; Kaerki, J.; Vainikka, P. (and others) [VTT, Jyvaskyla (Finland)

    2008-07-01

    Development of on-line monitoring tools is a key activity in the supervision, diagnosis and control of the impact of ash fouling on the efficiency and operation of large co-fired boilers. These monitoring tools have to be based both on the design of new measurement practices an don the mathematical modelling of the physical processes, aiming at the accurate determination of the deposition rates. The ADMONI-project aim was to develop on-line calculation methods for plant performance monitoring. The project focused on the design of a new pilot and power plant scale deposition probes, the execution of co-firing tests in experimental rigs and on the power plants and the development of monitoring tools to detect fouling rates both under pilot and full-scale perspectives. 43 refs., 142 figs., 13 tabs.

  10. Analysis of Chemical Reaction Kinetics Behavior of Nitrogen Oxide During Air-staged Combustion in Pulverized Boiler

    Directory of Open Access Journals (Sweden)

    Jun-Xia Zhang

    2016-03-01

    Full Text Available Because the air-staged combustion technology is one of the key technologies with low investment running costs and high emission reduction efficiency for the pulverized boiler, it is important to reveal the chemical reaction kinetics mechanism for developing various technologies of nitrogen oxide reduction emissions. At the present work, a three-dimensional mesh model of the large-scale four corner tangentially fired boiler furnace is established with the GAMBIT pre-processing of the FLUENT software. The partial turbulent premixed and diffusion flame was simulated for the air-staged combustion processing. Parameters distributions for the air-staged and no the air-staged were obtained, including in-furnace flow field, temperature field and nitrogen oxide concentration field. The results show that the air-staged has more regular velocity field, higher velocity of flue gas, higher turbulence intensity and more uniform temperature of flue gas. In addition, a lower negative pressure zone and lower O2 concentration zone is formed in the main combustion zone, which is conducive to the NO of fuel type reduced to N2, enhanced the effect of NOx reduction. Copyright © 2016 BCREC GROUP. All rights reserved Received: 5th November 2015; Revised: 14th January 2016; Accepted: 16th January 2016  How to Cite: Zhang, J.X., Zhang, J.F. (2016. Analysis of Chemical Reaction Kinetics Behavior of Nitrogen Oxide During Air-staged Combustion in Pulverized Boiler. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (1: 100-108. (doi:10.9767/bcrec.11.1.431.100-108 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.11.1.431.100-108

  11. VARTM Process Modeling of Aerospace Composite Structures

    Science.gov (United States)

    Song, Xiao-Lan; Grimsley, Brian W.; Hubert, Pascal; Cano, Roberto J.; Loos, Alfred C.

    2003-01-01

    A three-dimensional model was developed to simulate the VARTM composite manufacturing process. The model considers the two important mechanisms that occur during the process: resin flow, and compaction and relaxation of the preform. The model was used to simulate infiltration of a carbon preform with an epoxy resin by the VARTM process. The model predicted flow patterns and preform thickness changes agreed qualitatively with the measured values. However, the predicted total infiltration times were much longer than measured most likely due to the inaccurate preform permeability values used in the simulation.

  12. Declarative business process modelling: principles and modelling languages

    Science.gov (United States)

    Goedertier, Stijn; Vanthienen, Jan; Caron, Filip

    2015-02-01

    The business process literature has proposed a multitude of business process modelling approaches or paradigms, each in response to a different business process type with a unique set of requirements. Two polar paradigms, i.e. the imperative and the declarative paradigm, appear to define the extreme positions on the paradigm spectrum. While imperative approaches focus on explicitly defining how an organisational goal should be reached, the declarative approaches focus on the directives, policies and regulations restricting the potential ways to achieve the organisational goal. In between, a variety of hybrid-paradigms can be distinguished, e.g. the advanced and adaptive case management. This article focuses on the less-exposed declarative approach on process modelling. An outline of the declarative process modelling and the modelling approaches is presented, followed by an overview of the observed declarative process modelling principles and an evaluation of the declarative process modelling approaches.

  13. Process and Context in Choice Models

    DEFF Research Database (Denmark)

    Ben-Akiva, Moshe; Palma, André de; McFadden, Daniel

    2012-01-01

    We develop a general framework that extends choice models by including an explicit representation of the process and context of decision making. Process refers to the steps involved in decision making. Context refers to factors affecting the process, focusing in this paper on social networks. The...

  14. Will Rule based BPM obliterate Process Models?

    NARCIS (Netherlands)

    Joosten, S.; Joosten, H.J.M.

    2007-01-01

    Business rules can be used directly for controlling business processes, without reference to a business process model. In this paper we propose to use business rules to specify both business processes and the software that supports them. Business rules expressed in smart mathematical notations bring

  15. Exergy analysis of boiler of the steam power plant : case study in Iran

    Energy Technology Data Exchange (ETDEWEB)

    Gorji, M.; Ebrahimian, V. [Mazandaran Univ., Babol (Iran, Islamic Republic of). Dept. of Mechanical Engineering

    2006-07-01

    An exergy analysis was conducted to investigate the efficiency of a power plant in Iran. The plant consisted of 4 steam cycle units and 3 turbines of varying pressures using both natural gas and diesel fuel scenarios. The boiler had natural circulation with a 3-staged superheater and 2-stage reheaters and economizers. Energy and exergy balance equations were used to calculate efficiencies. The analysis showed that the total exergy efficiency of the plant was 36.1 per cent for the natural gas scenario and 35.5 per cent for the diesel fuel scenario. Among the main elements of the plant cycle, the highest exergy losses occurred with the boiler. Internal losses of the boiler included heat transfer, combustion, and friction losses, which were estimated at 362899 kW for the natural gas scenario and 411127 MW for the diesel fuel scenario. Exergy losses were primarily due to the exiting of hot gases from the chimney. Exergy losses caused by heat transfer were greater than the exergy losses of the combustion process. The exergy analysis of the boiler elements showed that the reheater had the lowest exergy efficiency and that the evaporator had the highest exergy losses. Results suggested that natural gas was more efficient than diesel fuel for producing superheater vapor in the boiler. It was concluded that the simulation can be used for steam power plants using both natural gas and diesel fuel. 13 refs., 5 tabs., 12 figs.

  16. 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...

  17. 40 CFR 761.71 - High efficiency boilers.

    Science.gov (United States)

    2010-07-01

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

  18. 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...

  19. 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...

  20. 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.