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Sample records for boiler composite floor

  1. 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.

  2. Steel-board composite floors

    NARCIS (Netherlands)

    Couchman, G.H.; Tomà, A.W.; Brekelmans, J.W.P.M.; Brande, E.L.M.G. van den

    1999-01-01

    Work currently underway in Holland aDd the UK aims to increase the already considerable potential for light steel framing in buildings by developing rules for so-called "dry composites". This paper discusses both theoretical and experimental work to develop validated design mies for floor systems co

  3. Steel-board composite floors

    NARCIS (Netherlands)

    Couchman, G.H.; Tomà, A.W.; Brekelmans, J.W.P.M.; Brande, E.L.M.G. van den

    1999-01-01

    Work currently underway in Holland aDd the UK aims to increase the already considerable potential for light steel framing in buildings by developing rules for so-called "dry composites". This paper discusses both theoretical and experimental work to develop validated design mies for floor systems

  4. Timber-concrete composite floor systems

    NARCIS (Netherlands)

    Linden, M.L.R. van der; Blass, H.J.

    1996-01-01

    Timber-concrete composite (tcc) beams may be used for the renovation of old timber floors. Although these systems are a simple and practical solution, they are not widely adopted. One of the reasons for this is the lack of uniform design mies. In this research programme shear tests on four different

  5. Timber-concrete composite floor systems

    NARCIS (Netherlands)

    Linden, M.L.R. van der; Blass, H.J.

    1996-01-01

    Timber-concrete composite (tcc) beams may be used for the renovation of old timber floors. Although these systems are a simple and practical solution, they are not widely adopted. One of the reasons for this is the lack of uniform design mies. In this research programme shear tests on four different

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-07-01

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

  7. An Analytical Study on Deflection and Stress Resultants of Composite Floor Slabs

    OpenAIRE

    山川, 哲雄; 郝, 洪濤; 田中, 躍一; Yamakawa, Tetsuo; Hao, Hongtao; Tanaka, Youichi

    1993-01-01

    The composite floor slab, which is composed of cast-in-place concrete and casting floor formworks, is assumed to be a double layered floor slab. This floor slab is proposed as ARC (Automation-oriented Reinforced Concrete Constructions) floor systems.Using the equivalent flexural rigidity for the double layered floor slabs consisting of two different elastic moduli, analytical solutions expressed in Fourier series by thin plate theory and by elementary beam theory can be easily applied to the ...

  8. Application of Engineered Cementitious Composites (ECC) in modular floor panels

    DEFF Research Database (Denmark)

    Lárusson, Lárus Helgi; Fischer, Gregor; Jönsson, Jeppe

    2008-01-01

    This paper describes the design, manufacturing, and structural behavior of a prefabricated floor panel consisting of a modular assembly of a thin-walled ECC slab and steel truss girders. The features of this composite structure include light weight, the modular manufacturing process...... with adaptability to various loading requirements, and the efficient utilization of material resources and industrial byproducts. The work described in this paper is a continuation of previous activities on composite floor panels in which light gage steel joists were integrally cast with the ECC slab. The modular...... concept introduced in this paper aims at improvements in the manufacturing process of the panels by casting the ECC slab separately and subsequently joining it with the steel trusses. The focus of this paper is on design and manufacturing of a prototype modular panel and on its structural behavior under...

  9. The Influence of the Thickness of the Slab and Concrete Grade on Composite Floors

    OpenAIRE

    Vasile-Mircea Venghiac; Cedric D’Mello

    2010-01-01

    A modern flooring system is the ComFloor Composite Floor Deck from Corus. This type of floor has many advantages involving cost, weight, construction speed, but also disadvantages regarding vibrations induced by human activity. The vibration behaviour of this system was analysed taking into consideration two parameters: the thickness of the slab and the grade of the concrete. Two sets of models were made, one with composite beams and one with steel beams. The purpose was to make a comparison ...

  10. The Influence of the Thickness of the Slab and Concrete Grade on Composite Floors

    Directory of Open Access Journals (Sweden)

    Vasile-Mircea Venghiac

    2010-01-01

    Full Text Available A modern flooring system is the ComFloor Composite Floor Deck from Corus. This type of floor has many advantages involving cost, weight, construction speed, but also disadvantages regarding vibrations induced by human activity. The vibration behaviour of this system was analysed taking into consideration two parameters: the thickness of the slab and the grade of the concrete. Two sets of models were made, one with composite beams and one with steel beams. The purpose was to make a comparison between these two types of flooring systems. Results showed a good improvement created by the composite action of the beams and usefull information regarding the two parameters considered.

  11. Comparisons of venus surface compositions with terrestrial ocean floor rocks

    Energy Technology Data Exchange (ETDEWEB)

    Garvin, J.B.; Bryan, W.B.

    1987-10-01

    Statistical comparison of Venera and Vega lander x-ray fluorescence spectrometer measurements of the composition of the Venus surface with an extensive database of compositional data for terrestrial ocean floor rocks indicates that the Venera 14 data matches certain tholeiitic basalts from the Kane Fracture Zone (KFZ) in the Mid-Atlantic Ridge (22-25/sup 0/N) at high confidence levels. The tholeiites most similar to the Venera measurements are very primitive, low-calcium, high-alumina pillow basalts depleted in clinopyroxene, and are relatively unique to certain fracture zones in oceanic regions. If the Venera 14 analogy is valid, the implication is that certain Venus basaltic magmas have lost clinopyroxene at relatively high pressures by fractionation, perhaps within a deep source region. Comparisons of Venera 13 and Vega 2 data with oceanic rocks yield poorer matches. Venera 13 matches Loihi seamount alkali basalts, as well as potassic mafic rocks from oceanic island such as Tristan de Cunha. The best analogy to Vega 2 may be altered gabbros or basic lavas from terrestrial basic intrusions such as the Troodos ophiolite. The close similarity of a representative sample of Venera 14 material with distinctive ocean floor tholeiitic basalts suggests that deep magma storage regions exist on Venus, and that derivation of both tholeiitic and alkalic magmas from a single primitive parent may be an important process on Venus.

  12. Effect of Rare Earth Composite Ceramic Materials on Oil Combustion of Oil-Burning Boiler

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The rare earth composite ceramic materials were prepared using rare earths and far infrared natural mineral. The effects of the as-prepared ceramic materials on the oil consumption and air pollutants emissions of oil-burning boiler were investigated. The results show that the composite ceramic materials can radiate higher intensity of far infrared. The molecular movement is strengthened and the chemical bonds of the molecules are easily ruptured when the diesel oil is dealt with the composite materials. The oil-saving rate of the RBS·VH-1.5 boiler dealt with the rare earth composite ceramic materials is 3.49%, and the reducing rates of CO and NO in the exhaust gas are 25.4% and 9.7%, respectively.

  13. Spray washing, absorbent corn starch powder and dry time to reduce bacterial numbers on soiled boiler transport cage flooring

    Science.gov (United States)

    Most broilers in the U.S. are transported live to slaughter facilities in cages with fiberglass floors. Cages are often used repeatedly without washing and fecal matter deposited on the floor surface can transfer Campylobacter from one flock to another. Drying feces out between uses is an effectiv...

  14. 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.

  15. Fabrication of patient specific composite orbital floor implants by stereolithography

    NARCIS (Netherlands)

    Geven, Mike A.; Varjas, Viktor; Kamer, Lukas; Wang, Xinjiang; Peng, Jiang; Eglin, David; Grijpma, Dirk W.

    2015-01-01

    Fractures of the orbital floor are common in traffic accidents and assaults, and inadequate treatment can result in serious complications. Accurate anatomical reconstruction of the orbit using implants is the preferred treatment. Implants require degradability, adequate mechanical properties to supp

  16. An experimental investigation of composite floor vibration due to human activities. A case study

    Directory of Open Access Journals (Sweden)

    Yasser G. Mohamed Fahmy

    2012-12-01

    Full Text Available Composite steel floor decks are used in a large variety of constructions with long spans, such as administration and commercial buildings, hotels and bridges. Due to decreased floor mass and longer span lengths, floor vibrations have become an area of concern. Floor decks with low frequencies may be in resonance with the vibrations due to human activities and the resulting acceleration may exceed human comfort levels. The design of slender floor structures, with steel or composite cross sections, is often limited by the serviceability criteria such as deflection limits and vibration behavior, rather than the strength criteria. Control of deflections under AISC specifications requirement is not enough to satisfy the serviceability requirements of the floor systems for vibration. In addition, vibration analysis procedures introduced by AISC design Guide No. 11 are based on regularly-shaped structures and simple boundary conditions. In this paper, a case study for full scale testing of a composite floor system proposed for a tower at Kuwait state that was tested prior to construction. The heel-drop and walking tests are performed on floor systems with and without raised floor respectively. Since heel-drop and walking test results would vary in light of person performance, both tests are carried out three or four times to reduce uncertainty. The fundamental frequencies and damping ratio of the floor system are measured. Comparison of the experimental results with results based on the AISC hand calculations shows that there is no significant difference; therefore the results based on AISC are generally acceptable.

  17. 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.

  18. Nanosilica reinforced epoxy floor coating composites: preparation and thermophysical characterization

    Directory of Open Access Journals (Sweden)

    Mir Mohammad Alavi Nikje

    2012-01-01

    Full Text Available In this study, flooring grade epoxy/nanoSiO2 nanocomposites were prepared by in-situ polymerization method. Nano silica was treated by coupling agent in order to surface treating and introducing of reactive functional groups to achieving adequate bonding between polar inorganic nano particles and epoxy organic polymer. γ-Aminopropyltriethoxysilane (Amino A-100 was used as an effective and commercially available coupling agent and nano silica treated in acetone media. SEM observations of cured samples revealed that the nano silica was completely dispersed into polymer matrix into nanoscale particles. Thermal and physical properties of prepared samples were investigated and data showed improvements in physical and mechanical properties of the flooring samples in comparison with unfilled resin.

  19. Experimental and analytical study of the effects of floor location on response of composite fuselage frames

    Science.gov (United States)

    Jones, Lisa E.; Robinson, Martha; Fasanella, Edwin L.; Boitnott, Richard L.

    1992-01-01

    Experimental and analytical results are presented of the effects of floor placement on the structural response and strength of I-cross section, semi-circular fuselage frames constructed of graphite-epoxy composite material. The composite frame configuration is representative of current conventional aircraft design. Experimental strain distributions are presented from static loading tests of the composite frames and compared with finite element structural models and closed form solutions. An understanding of floor location effects can aid dynamists in predicting the crash behavior of these conventional structures, and may assist the designer in developing crashworthy structures for future aircraft.

  20. Mineralogical composition of boiler fouling and slagging deposits and their relation to fly ashes: the case of Kardia power plant.

    Science.gov (United States)

    Kostakis, George

    2011-01-30

    Slagging and fouling deposits from a pulverized lignite fired steam generating unit of the Kardia power plant (West Macedonia, Greece) were mineralogically investigated. The structure and cohesion of these deposits varied, usually depending on the level height of the boiler unit where they were formed. Some of the deposits had complex phase composition. The dominant components of the deposits of the burner zone and of the lower and intermediate boiler zones were the amorphous, anhydrite and hematite, while those of the highest levels contained amorphous, and anhydrite. Furthermore, in deposits formed in various other boiler areas gehlenite, anorthite, diopside, quartz, Ca(2)SiO(4), brownmillerite and other crystalline phases were also identified, usually in low amounts or in traces. The major part of the phases constituting the deposits were formed in the boiler, since only a minor part derived from the unreacted minerals present in lignite. Anhydrite was generated from the reaction of SO(2) with CaO formed mainly by the calcination of calcite as well as from dehydration of gypsum contained in lignite, while hematite was produced mainly from the oxidation of pyrite. The calcium-containing silicates formed in the boiler were mainly the products of reactions between CaO and minerals contained in the lignite.

  1. Impacts of Limestone Particle Size on the Performance of Flexible Wood Fiber Composite Floor

    Directory of Open Access Journals (Sweden)

    Hongcheng He

    2015-01-01

    Full Text Available Sustainable wood floor (WFF, produced from natural plants, is a sort of novel green and ecofriendly composite floor, which has been attracting more and more attention in the world. WFF also gives a solution of utilizations of agricultural wastes, such as bamboo mats and hemp hurd. The additive limestone powder plays key role in the performance of flexible bamboo composite floor, so, in this paper, the effects of limestone size and size distributions were investigated. The best particle size distributions of limestone are 25 wt% of 48 μm, 25 wt% of 106 μm, and 50 wt% of 160 μm. The as-obtained WFF has good elasticity, good affinity, and strong comfortableness as well as free formaldehyde release.

  2. The Design of a Semi-Prefabricated LVL-Concrete Composite Floor

    Directory of Open Access Journals (Sweden)

    David Yeoh

    2012-01-01

    Full Text Available This paper describes the design of a novel semi-prefabricated LVL-concrete composite floor that has been developed in New Zealand. In this solution, the floor units made from LVL joists and plywood are prefabricated in the factory and transported to the building site. The units are then lifted onto the supports and connected to the main frames of the building and to the adjacent units. Finally, a concrete topping is poured on top of the units in order to form a continuous slab connecting all the units. Rectangular notches cut from the LVL joists and reinforced with coach screws provide the composite action between the concrete slab and the LVL joists. This system proved to be an effective modular solution that ensures rapid construction. A design procedure based on the use of the effective flexural stiffness method, also known as the “gamma method” is proposed for the design of the composite floor at ultimate and serviceability limit states, in the short and long term. By comparison with the experimental results, it is shown that the proposed method leads to conservative design. A step-by-step design worked example of this novel semi-prefabricated composite floor concludes the paper.

  3. Effect of incremental filling technique on adhesion of light-cured resin composite to cavity floor.

    Science.gov (United States)

    Chikawa, Hirokazu; Inai, Norimichi; Cho, Eitetsu; Kishikawa, Ryuzo; Otsuki, Masayuki; Foxton, Richard M; Tagami, Junji

    2006-09-01

    The purpose of this study was to evaluate the effect of various incremental filling techniques on adhesion between composite and cavity floor using light-cured resin composite. Black ABS resin and hybrid resin composite were used as mold materials--instead of dentin--for the preparation of cavities, and standardized to 5x5x5 mm. Each cavity was then treated with a bonding system (Clearfil SE bond). Resin composite (Clearfil Photo Core) was placed on the bonding resin using different incremental filling techniques or in bulk and irradiated for a total of 80 seconds using a halogen light unit. Specimens were subjected to the micro-tensile bond test at a crosshead speed of 1 mm/min. Data were analyzed by two-way ANOVA. The results indicated that an incremental filling technique was more effective in improving adhesion to the cavity floor than a bulk filling technique.

  4. Gut microbiota composition is correlated to grid floor induced stress and behavior in the BALB/c mouse

    DEFF Research Database (Denmark)

    Bendtsen, Katja Maria Bangsgaard; Krych, Lukasz; Sørensen, Dorte Bratbo;

    2012-01-01

    to grid floor. Stressing the mice clearly changed the cecal microbiota as determined by both DGGE and pyrosequencing. Odoribacter, Alistipes and an unclassified genus from the Coriobacteriaceae family increased significantly in the grid floor housed mice. Compared to baseline, the mice exposed to grid...... the HbA1c level was significantly higher. It is concluded that grid floor housing changes the GM composition, which seems to influence certain anxiety-related parameters....

  5. TEMPERATURE HETEROGENEITY OF TRAVELLING FIRE AND ITS INFLUENCE ON COMPOSITE STEEL-CONCRETE FLOOR

    Directory of Open Access Journals (Sweden)

    Kamila Horová

    2016-04-01

    Full Text Available In order to follow modern trends in contemporary building architecture, which is moving off the limits of current fire design models, assumption of homogeneous temperature conditions used for structural fire analysis needs to be revised. In this paper fire dynamics of travelling fire is investigated experimentally by conducting fire test in two-storey experimental building. To evaluate the impact of travelling fire on the mechanical behaviour of a structure, the spatial and temporal evolution of the gas temperature calculated in NIST code FDS, which was validated to experimental measurements, is applied to the composite floor of dimensions 9.0 m by 9.0 m. Mechanical behaviour of the composite slab highly affected by regions of high temperatures and areas with only elevated temperatures is solved in code Vulcan. To highlight the severity of spreading fire causing non-uniform temperature conditions, which after-effects differ from traditional methods, a comparison of both methods is introduced. The calculation of mechanical behaviour of the composite floor is repeated in a series of three different thermal loading cases. Results of all cases are then compared in terms of vertical displacement and axial force in several positions of the composite floor.

  6. 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.

  7. Decreasing vitamin premix on chicken carcass composition and blood chemistry in floor and battery cage systems

    Directory of Open Access Journals (Sweden)

    Mahmood Shivazad

    2012-01-01

    Full Text Available Two experiments were conducted the to compare the effect of a decreasing amount of vitamin premix in diets inbroilers from 29 to 42 days of age on carcass composition and blood chemistry in floor (Experiment 1 and battery cage (Experiment 2 systems. At 35 and 42 days of ages, one bird of each replicate was slaughtered and carcass composition was measured. Blood concentrations of alkaline phosphatase (ALP and Ca were used to diagnose vitamin D3 deficiency and enzymes aspartate amino transferase (AST to identify vitamin E deficiency. Floor raised birds showed that vitamin premix reduction/withdrawal at 29 days of age did not impair body weight (BW, carcass composition, ALP and Ca during the final rearing period. However, diet without vitamin premix (T1 had a higher AST at 42 days of age than the other diets. Birds reared in cages were slightly more sensitive to vitamin premix reduction/withdrawal, probably due to the impracticality of performing coprophagy. Diet without vitamin premix (T1 had a lower BW, carcass breast and thigh yield at 42 days of age; also serum ALP, AST and Ca were impaired. In conclusion, the withdrawal of vitamins is not a reasonable option but it is possible to reduce vitamin premix in finisher broilers’ diets without negative effects on performance and on some metabolic traits during the finisher period with both methods of rearing.

  8. Compositional differences between roof and floor rocks of the Skaergaard Intrusion

    Science.gov (United States)

    Salmonsen, Lars Peter; Tegner, Christian; Barfod, Gry H.; Lesher, Charles E.

    2014-05-01

    The Skaergaard intrusion solidified inwards from the margins forming the Layered Series on the floor and the Marginal and Upper Border Series on the walls and roof, respectively. Comparison of the roof and floor rocks is the most straight-forward way to contrast differentiation processes controlled by gravity. Here, we present new bulk rock (major and trace elements, Sr and Nd isotopes), mineralogical and petrographic data for the Upper Border Series. The Upper Border Series mainly diverge from equivalent Layered Series rocks by relatively higher concentrations of incompatible elements, lack of igneous lamination and frequent development of interstitial granophyre, whereas the core compositions of minerals and isotopic signatures are similar in the two series. Here, we examine the main explanations for these differences. Firstly, it has been suggested that the roof zone was enriched by assimilation of stoped gneissic blocks. Our new Sr and Nd data of the Upper Border Series exclude this as a first order process as has been shown before. Mixing models suggest that the Layered and Upper Border Series assimilated less than 3 percent Precambrian host gneiss. Furthermore, no correlation exists between incompatible elements and Sr-Nd isotopic ratios. Secondly, magma stratification as a consequence of compositional convection has been invoked. However, by combining petrography and whole rock compositions we show that the crystallization sequence in the Upper Border Series is identical to the Layered Series. Moreover, the anorthite content of plagioclase cores is identical within error in the roof and floor at the cumulus phase boundaries. This is most easily explained by in situ crystallization inwards from the margins of a homogeneous magma. Thirdly, the enrichment of incompatible elements in the Upper Border Series relative to the Layered Series has been explained by the trapping of a higher fraction of intercumulus liquid in the roof rocks relative to the compacted

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-10-01

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

  10. Compositional differences between roof and floor rocks of the Skaergaard Intrusion

    DEFF Research Database (Denmark)

    Salmonsen, Lars Peter; Tegner, Christian; Barfod, Gry

    2014-01-01

    lamination and frequent development of interstitial granophyre, whereas the core compositions of minerals and isotopic signatures are similar in the two series. Here, we examine the main explanations for these differences. Firstly, it has been suggested that the roof zone was enriched by assimilation...... Border Series relative to the Layered Series has been explained by the trapping of a higher fraction of intercumulus liquid in the roof rocks relative to the compacted floor cumulates. Our data corroborates this interpretation. They also confirm that the concentrations of incompatible elements in certain...... levels of the roof rocks exceed what can be explained by trapped liquid contents. This is explained by instability of the upper solidification front and infiltration of evolved liquid into tension gashes. Fourthly, recent melt inclusion and textural studies show that the magma exsolved into immiscible Fe...

  11. Gut microbiota composition is correlated to grid floor induced stress and behavior in the BALB/c mouse.

    Directory of Open Access Journals (Sweden)

    Katja Maria Bangsgaard Bendtsen

    Full Text Available Stress has profound influence on the gastro-intestinal tract, the immune system and the behavior of the animal. In this study, the correlation between gut microbiota composition determined by Denaturing Grade Gel Electrophoresis (DGGE and tag-encoded 16S rRNA gene amplicon pyrosequencing (454/FLX and behavior in the Tripletest (Elevated Plus Maze, Light/Dark Box, and Open Field combined, the Tail Suspension Test, and Burrowing in 28 female BALB/c mice exposed to two weeks of grid floor induced stress was investigated. Cytokine and glucose levels were measured at baseline, during and after exposure to grid floor. Stressing the mice clearly changed the cecal microbiota as determined by both DGGE and pyrosequencing. Odoribacter, Alistipes and an unclassified genus from the Coriobacteriaceae family increased significantly in the grid floor housed mice. Compared to baseline, the mice exposed to grid floor housing changed the amount of time spent in the Elevated Plus Maze, in the Light/Dark Box, and burrowing behavior. The grid floor housed mice had significantly longer immobility duration in the Tail Suspension Test and increased their number of immobility episodes from baseline. Significant correlations were found between GM composition and IL-1α, IFN-γ, closed arm entries of Elevated Plus Maze, total time in Elevated Plus Maze, time spent in Light/Dark Box, and time spent in the inner zone of the Open Field as well as total time in the Open Field. Significant correlations were found to the levels of Firmicutes, e.g. various species of Ruminococccaceae and Lachnospiraceae. No significant difference was found for the evaluated cytokines, except an overall decrease in levels from baseline to end. A significant lower level of blood glucose was found in the grid floor housed mice, whereas the HbA1c level was significantly higher. It is concluded that grid floor housing changes the GM composition, which seems to influence certain anxiety

  12. Gut microbiota composition is correlated to grid floor induced stress and behavior in the BALB/c mouse.

    Science.gov (United States)

    Bangsgaard Bendtsen, Katja Maria; Krych, Lukasz; Sørensen, Dorte Bratbo; Pang, Wanyong; Nielsen, Dennis Sandris; Josefsen, Knud; Hansen, Lars H; Sørensen, Søren J; Hansen, Axel Kornerup

    2012-01-01

    Stress has profound influence on the gastro-intestinal tract, the immune system and the behavior of the animal. In this study, the correlation between gut microbiota composition determined by Denaturing Grade Gel Electrophoresis (DGGE) and tag-encoded 16S rRNA gene amplicon pyrosequencing (454/FLX) and behavior in the Tripletest (Elevated Plus Maze, Light/Dark Box, and Open Field combined), the Tail Suspension Test, and Burrowing in 28 female BALB/c mice exposed to two weeks of grid floor induced stress was investigated. Cytokine and glucose levels were measured at baseline, during and after exposure to grid floor. Stressing the mice clearly changed the cecal microbiota as determined by both DGGE and pyrosequencing. Odoribacter, Alistipes and an unclassified genus from the Coriobacteriaceae family increased significantly in the grid floor housed mice. Compared to baseline, the mice exposed to grid floor housing changed the amount of time spent in the Elevated Plus Maze, in the Light/Dark Box, and burrowing behavior. The grid floor housed mice had significantly longer immobility duration in the Tail Suspension Test and increased their number of immobility episodes from baseline. Significant correlations were found between GM composition and IL-1α, IFN-γ, closed arm entries of Elevated Plus Maze, total time in Elevated Plus Maze, time spent in Light/Dark Box, and time spent in the inner zone of the Open Field as well as total time in the Open Field. Significant correlations were found to the levels of Firmicutes, e.g. various species of Ruminococccaceae and Lachnospiraceae. No significant difference was found for the evaluated cytokines, except an overall decrease in levels from baseline to end. A significant lower level of blood glucose was found in the grid floor housed mice, whereas the HbA1c level was significantly higher. It is concluded that grid floor housing changes the GM composition, which seems to influence certain anxiety-related parameters.

  13. Control of formaldehyde and TVOC emission from wood-based flooring composites at various manufacturing processes by surface finishing.

    Science.gov (United States)

    Kim, Sumin

    2010-04-15

    This paper assesses the reproducibility of testing formaldehyde and TVOC emission behavior from wood flooring composites bonded by urea-formaldehyde resin at various manufacturing steps for surface finishing materials. The surface adhesion step of laminate flooring for this research was divided into two steps; HDF only and HDF with LPMs. In the case of engineered flooring, the manufacturing steps were divided into three steps; plywood only, fancy veneer bonded on plywood and UV coated on fancy veneer with plywood. Formaldehyde and VOCs emission decreased at the process of final surface finishing materials; LPMs were applied on the surface of HDF for laminate flooring. Although emissions increased when fancy veneer was bonded onto plywood in the case of engineered flooring, emission was dramatically reduced up to similar level with plywood only when final surface finishing; UV-curable coating was applied on fancy veneer. This study suggests that formaldehyde and VOCs emission from floorings can be controlled at manufacturing steps for surface finishing. 2009 Elsevier B.V. All rights reserved.

  14. Changes in forest floor composition and chemistry along an invasive earthworm gradient in a hardwood forest

    Science.gov (United States)

    Jourdain, J. N.; Filley, T. R.; Top, S. M.; Thayer, C.; Johnson, A.; Jenkins, M.; Welle, P.; Zurn-Birkhimer, S.; Kroeger, T.; Gemscholars

    2010-12-01

    Recent studies have demonstrated how invasive European earthworm species have caused large and long lasting perturbations to forest floor dynamics and soil composition in many northern hardwood forests. The type of perturbation is driven primarily by the composition and activity of the invasive species and the original state of the forest system. Over the past 4 years we have investigated an invasive earthworm front moving through the Ojibwa Red Lake Reservation (Minnesota). Significant shifts in litter and organic horizon mass were observed, similar to other gradients identified in the region, but the species of earthworms exhibited differences compared to other reservation lands in the region--possibly driven by the availability of recreation fishing near to the sites. Sharp gradients in earthworm abundance were observed exhibiting shifts from 600- 900 individuals per meter square to no observed worms within only 500 meters. The gradients in earthworm activity also influenced decay rates of litter, as was observed by placement of litter decay bags across the gradient. Our findings demonstrate the tenuous nature of many tribal reservation forests and point to the need for policies to address spread on such species to minimize impacts to soil carbon stocks as well as culturally important plant species.

  15. Flue gas dust composition and fouling tendency in recovery boilers; Flygaskans sammansaettning och nedsmutsande tendens i sodapannan

    Energy Technology Data Exchange (ETDEWEB)

    Forssen, Mikael; Backman, Rainer; Wallen, Jonas; Hupa, Mikko [Aabo Akademi (Finland)

    2000-02-01

    In this work eight Swedish black liquors have been characterized for the following properties: Combustability and bed behavior; Dust formation tendency; Fouling tendency of dust; SO{sub 2} formation tendency; and, NO formation tendency. The research was made using; (i) chemical analysis of the samples, (ii) special laboratory scale combustion and pyrolysis tests and (iii) an advanced computer model (Recovery Boiler Chemistry Advisor) for calculating the chemical composition and melting properties of the flue gas dust (fly ash). All tests and analysis were successfully performed and the results were reproducible and reliable. The results were classified for each of the five properties from one to five, and summarised into a table. The liquors showed good or extremely good combustability, also the behavior of the bed was normal or extremely good. None of the liquors had extremely high or low values in their swelling tendency or in their total combustion times. The liquors showed bigger differences in their tendency to form dust. Most of the liquors were 'good' because of the lower than normal tendency to form dust during combustion. Only one of the liquors, liquor B, was rated as 'bad', one of the liquors, liquor E, was rated 'extremely good', in other words liquor B had the highest tendency to form dust whereas liquor E had the lowest tendency to form dust. The advanced computer modelling work gave the composition, and the melting properties for the two dust components, carry-over and the condensed dust. The fouling tendency of the liquors were extremely good (low), the differences were so small that no distinction could be made between the liquors. Compared to earlier studies, the sticky temperature, T{sub 15}, for the eight liquors were extremely high, for both modelling cases when the combustion was assumed to take place either in a 'cold' or in a 'hot' furnace. This is partly explained by the fact that the

  16. Floor interaction

    DEFF Research Database (Denmark)

    Petersen, Marianne Graves; Krogh, Peter; Ludvigsen, Martin;

    2005-01-01

    Within architecture, there is a long tradition of careful design of floors. The design has been concerned with both decorating floors and designing floors to carry information. Ubiquitous computing technology offers new opportunities for designing interactive floors. This paper presents three...... different interactive floor concepts. Through an urban perspective it draws upon the experiences of floors in architecture, and provides a set of design issues for designing interactive floors....

  17. Application of sandwich honeycomb carbon/glass fiber-honeycomb composite in the floor component of electric car

    Science.gov (United States)

    Sukmaji, I. C.; Wijang, W. R.; Andri, S.; Bambang, K.; Teguh, T.

    2017-01-01

    Nowadays composite is a superior material used in automotive component due to its outstanding mechanical behavior. The sandwich polypropylene honeycomb core with carbon/glass fiber composite skin (SHCG) as based material in a floor component of electric car application is investigated in the present research. In sandwich structure form, it can absorb noise better compare with the conventional material [1]. Also in present paper, Finite Element Analysis (FEA) of SHCG as based material for floor component of the electric car is analyzed. The composite sandwich is contained with a layer uniform carbon fiber and mixing non-uniform carbon-glass fiber in upper and lower skin. Between skins of SHCG are core polypropylene honeycomb that it have good flexibility to form following dies profile. The variables of volume fraction ratio of carbon/glass fiber in SHCG skin are 20/80%, 30/70%, and 50/50%. The specimen of SHCG is tested using the universal testing machine by three points bending method refers to ASTM C393 and ASTM C365. The cross point between tensile strength to the volume fraction the mixing carbon/glass line and ratio cost line are the searched material with good mechanical performance and reasonable cost. The point is 30/70 volume fraction of carbon/glass fiber. The result of the testing experiment is become input properties of model structure sandwich in FEA simulation. FEA simulation approach is conducted to find critical strength and factor of complex safety geometry against varied distributed passenger loads of a floor component the electric car. The passenger loads variable are 80, 100, 150, 200, 250 and 300 kg.

  18. Gut Microbiota Composition Is Correlated to Grid Floor Induced Stress and Behavior in the BALB/c Mouse

    OpenAIRE

    Katja Maria Bangsgaard Bendtsen; Lukasz Krych; Dorte Bratbo Sørensen; Wanyong Pang; Dennis Sandris Nielsen; Knud Josefsen; Hansen, Lars H.; Sørensen, Søren J.; Axel Kornerup Hansen

    2012-01-01

    Stress has profound influence on the gastro-intestinal tract, the immune system and the behavior of the animal. In this study, the correlation between gut microbiota composition determined by Denaturing Grade Gel Electrophoresis (DGGE) and tag-encoded 16S rRNA gene amplicon pyrosequencing (454/FLX) and behavior in the Tripletest (Elevated Plus Maze, Light/Dark Box, and Open Field combined), the Tail Suspension Test, and Burrowing in 28 female BALB/c mice exposed to two weeks of grid floor ind...

  19. Statistical Energy Analysis (SEA) and Energy Finite Element Analysis (EFEA) Predictions for a Floor-Equipped Composite Cylinder

    Science.gov (United States)

    Grosveld, Ferdinand W.; Schiller, Noah H.; Cabell, Randolph H.

    2011-01-01

    Comet Enflow is a commercially available, high frequency vibroacoustic analysis software founded on Energy Finite Element Analysis (EFEA) and Energy Boundary Element Analysis (EBEA). Energy Finite Element Analysis (EFEA) was validated on a floor-equipped composite cylinder by comparing EFEA vibroacoustic response predictions with Statistical Energy Analysis (SEA) and experimental results. Statistical Energy Analysis (SEA) predictions were made using the commercial software program VA One 2009 from ESI Group. The frequency region of interest for this study covers the one-third octave bands with center frequencies from 100 Hz to 4000 Hz.

  20. Online and Compositional Learning of Controllers with Application to Floor Heating

    DEFF Research Database (Denmark)

    Larsen, Kim Guldstrand; Mikučionis, Marius; Muniz, Marco

    2016-01-01

    Controller synthesis for stochastic hybrid switched systems, like e.g. a floor heating system in a house, is a complex computational task that cannot be solved by an exhaustive search though all the control options. The state-space to be explored is in general uncountable due to the presence...... possible input temperatures and an arbitrary time horizon, we propose an on-line synthesis methodology, where we periodically compute the controller only for the near future based on the current sensor readings. This computation is itself done by employing machine learning in order to avoid enumeration...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-02-15

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

  2. Differences in the composition of organic impurities in ground and surface waters. Consequences for the preparation of boiler feed water

    Energy Technology Data Exchange (ETDEWEB)

    Huber, S.A. [DOC-Labor Dr. Huber, Karlsruhe (Germany)

    2002-07-01

    It is generally accepted that current limits for total organic carbon (TOC) in the pharmaceutical industry (500 ppb) and semiconductor industry (10-25 ppb) should be regarded as precautionary measures and do not necessarily reflect true scientific evidence. For the power industry the situation is different. Here, recommended TOC-limits for boiler feed waters (in 1999: VGB: 200 ppb; EPRI: 100 ppb) are based on scientific and empirical data. The oxidation of, say, 50 ppb TOC to carbon dioxide in the water/steam cycle will increase steam condensate conductivity by 0.48 {mu}{sup S}/cm (values may depend on literature source, here [1]), a value which is not acceptable as it desensitizes the detection of leaks in cooling water heat exchangers. Apart from this indirect effect of TOC there is also evidence for direct negative effects of TOC on steel materials. Even small amounts of organic acids, which are produced as intermediates in the TOC oxidation process, may locally lower the pH down to levels [2] where erosion corrosion of boiler tubes can take place. It was also found that carbon is enriched in stress corrosion cracks of turbine materials [3]. The present paper will discuss the ''TOC-issue'' in boiler feed water preparation. Most of the results can be applied also to other industries, e.g. semiconductor, chemical or pharmaceutical. (authors)

  3. Laboratory study of fungal bioreceptivity of different fractions of composite flooring tiles showing efflorescence.

    Science.gov (United States)

    Masaphy, Segula; Lavi, Ido; Sultz, Stephan; Zabari, Limor

    2014-06-01

    Fungi can grow in extreme habitats, such as natural stone and mineral building materials, sometimes causing deterioration. Efflorescence-concentrated salt deposits-results from water movement through building material; it can damage masonry materials and other bricks. Fungal isolate KUR1, capable of growth on, and dissolution of stone chips composing terrazzo-type floor tiles, was isolated from such tiles showing fiber-like crystalline efflorescence. The isolate's ribosomal DNA sequences were 100 % identical to those of Nigrospora sphaerica. The ability of KUR1 to colonize and degrade the different stone chips composing the tiles was studied in axenic culture experiments. When exposed to each of the different mineral chip types composed of dolomite, calcite, or calcite-apatite mineral in low-nutrition medium, the fungus showed selective nutrient consumption, and different growth and stone mineral dissolution rates. Micromorphological examination of the fungus-colonized chips by electron microscopy showed the production of a fungal biofilm with thin films around the hyphae on the surface of the examined chips and disintegration of the calcite-apatite fraction. More than 70 % dissolution of the introduced powdered (mineral was obtained within 10 days of incubation for the soft calcite-apatite fraction.

  4. Cermet composite thermal spray coatings for erosion and corrosion protection in combustion environments of advanced coal-fired boilers. Semiannual technical report, January 14, 1997--August 14, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Schorr, B.S.; Levin, B.F.; DuPont, J.N.; Marder, A.R.

    1997-08-31

    Research is presently being conducted to determine the optimum ceramic/metal combination in thermally sprayed metal matrix composite coatings for erosion and corrosion resistance in new coal-fired boilers. The research will be accomplished by producing model cermet composites using powder metallurgy and electrodeposition methods in which the effect of ceramic/metal combination for the erosion and corrosion resistance will be determined. These results will provide the basis for determining the optimum hard phase constituent size and volume percent in thermal spray coatings. Thermal spray coatings will be applied by our industrial sponsor and tested in our erosion and corrosion laboratories. Bulk powder processed Ni-Al{sub 2}O{sub 3} composites were produced at Idaho National Engineering Laboratory. The composite samples contained 0, 21, 27, 37, and 45 volume percent Al{sub 2}O{sub 3} with an average particle size of 12 um. Also, to deposit model Ni-Al{sub 2}O{sub 3} coatings, an electrodeposition technique was developed and coatings with various volume fractions (0-35%) of Al{sub 2}O{sub 3} were produced. The powder and electrodeposition processing of Ni-Al{sub 2}O{sub 3} Composites provide the ability to produce two phase microstructure without changing the microstructure of the matrix material. Therefore, the effect of hard second phase particles size and volume fraction on erosion resistance could be analyzed.

  5. Mercury isotopic composition of hydrothermal systems in the Yellowstone Plateau volcanic field and Guaymas Basin sea-floor rift

    Science.gov (United States)

    Sherman, L.S.; Blum, J.D.; Nordstrom, D.K.; McCleskey, R.B.; Barkay, T.; Vetriani, C.

    2009-01-01

    To characterize mercury (Hg) isotopes and isotopic fractionation in hydrothermal systems we analyzed fluid and precipitate samples from hot springs in the Yellowstone Plateau volcanic field and vent chimney samples from the Guaymas Basin sea-floor rift. These samples provide an initial indication of the variability in Hg isotopic composition among marine and continental hydrothermal systems that are controlled predominantly by mantle-derived magmas. Fluid samples from Ojo Caliente hot spring in Yellowstone range in δ202Hg from - 1.02‰ to 0.58‰ (± 0.11‰, 2SD) and solid precipitate samples from Guaymas Basin range in δ202Hg from - 0.37‰ to - 0.01‰ (± 0.14‰, 2SD). Fluid samples from Ojo Caliente display mass-dependent fractionation (MDF) of Hg from the vent (δ202Hg = 0.10‰ ± 0.11‰, 2SD) to the end of the outflow channel (&delta202Hg = 0.58‰ ± 0.11‰, 2SD) in conjunction with a decrease in Hg concentration from 46.6pg/g to 20.0pg/g. Although a small amount of Hg is lost from the fluids due to co-precipitation with siliceous sinter, we infer that the majority of the observed MDF and Hg loss from waters in Ojo Caliente is due to volatilization of Hg0(aq) to Hg0(g) and the preferential loss of Hg with a lower δ202Hg value to the atmosphere. A small amount of mass-independent fractionation (MIF) was observed in all samples from Ojo Caliente (Δ199Hg = 0.13‰ ±1 0.06‰, 2SD) but no significant MIF was measured in the sea-floor rift samples from Guaymas Basin. This study demonstrates that several different hydrothermal processes fractionate Hg isotopes and that Hg isotopes may be used to better understand these processes.

  6. Design of the composite flooring slab with profiled sheets t-153 (ruukki) for a residential building

    OpenAIRE

    Alysheva, Stanislava

    2015-01-01

    The purpose of the thesis was to analyse the structure of the composite slab with profiled sheets as permanent formwork; to work with Russian building norms and carry out the limit state design in order to determine characteristics of the structure and find out if it can be used in residential buildings. The study was commissioned by engineers of company Ruukki rus as they are willing to expand their market from designing industrial buildings to residential apartments. An excel file was cr...

  7. Construction Technology Analysis of Concrete Composite Box Net Floor%混凝土叠合箱网梁楼盖施工技术分析

    Institute of Scientific and Technical Information of China (English)

    叶雷杰

    2014-01-01

    Concrete composite box net floor is a special ribbed slab floor, from prefabricated composite box and cast nets (rib) beam combination, its characteristic is flat at the botom, saving materials and large cavity net beam structure stress. The author combining with practical experiences makes a simple analysis of the composite box net beamceiling te- chnique in this paper.%混凝土叠合箱网梁楼盖是一种特殊的密肋梁楼盖,由预制叠合箱和现浇网(肋)梁组合而成,特点是底部平整、节约耗材和大空腔网梁构造受力等。笔者结合实际经验,在本文中简单地分析了叠合箱网梁楼盖技术。

  8. POLY(TRIMETHYLENE CARBONATE) AND BIPHASIC CALCIUM PHOSPHATE COMPOSITES FOR ORBITAL FLOOR RECONSTRUCTION : A FEASIBILITY STUDY IN SHEEP

    NARCIS (Netherlands)

    van Leeuwen, A. C.; Yuan, H.; Passanisi, G.; van der Meer, J. W.; de Bruijn, J. D.; van Kooten, T. G.; Grijpma, D. W.; Bos, R. R. M.

    2014-01-01

    In the treatment of orbital floor fractures, bone is ideally regenerated. The materials currently used for orbital floor reconstruction do not lead to the regeneration of bone. Our objective was to render polymeric materials based on poly(trimethylene carbonate) (PTMC) osteoinductive, and to evaluat

  9. Gut microbiota composition is correlated to grid floor induced stress and behavior in the BALB/c mouse

    DEFF Research Database (Denmark)

    Bendtsen, Katja Maria Bangsgaard; Krych, Lukasz; Sørensen, Dorte Bratbo

    2012-01-01

    ) and behavior in the Tripletest (Elevated Plus Maze, Light/Dark Box, and Open Field combined), the Tail Suspension Test, and Burrowing in 28 female BALB/c mice exposed to two weeks of grid floor induced stress was investigated. Cytokine and glucose levels were measured at baseline, during and after exposure...... to grid floor. Stressing the mice clearly changed the cecal microbiota as determined by both DGGE and pyrosequencing. Odoribacter, Alistipes and an unclassified genus from the Coriobacteriaceae family increased significantly in the grid floor housed mice. Compared to baseline, the mice exposed to grid...... floor housing changed the amount of time spent in the Elevated Plus Maze, in the Light/Dark Box, and burrowing behavior. The grid floor housed mice had significantly longer immobility duration in the Tail Suspension Test and increased their number of immobility episodes from baseline. Significant...

  10. 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.

  11. Effect of species composition on carbon and nitrogen stocks in forest floor and mineral soil in Norway spruce and European beech mixed forests

    Science.gov (United States)

    Andivia, Enrique; Rolo, Víctor; Jonard, Mathieu; Formánek, Pavel; Ponette, Quentin

    2015-04-01

    Management of existing forests has been identified as the main strategy to enhance carbon sequestration and to mitigate the impact of climate change on forest ecosystems. In this direction, the conversion of Norway spruce monospecific stands into mixed stands by intermingling individuals of European beech is an ongoing trend in adaptive forest management strategies, especially in Central Europe. However, studies assessing the effect of changes in tree species composition on soil organic carbon (SOC) and nitrogen stocks are still scarce and there is a lack of scientific evidence supporting tree species selection as a feasible management option to mitigate the effects of predicted future climatic scenarios. We compared C and N stocks in the forest floor (litter and humus) and the top 10 cm of mineral soil in two monospecific stands of Norway spruce and European beech and in a mixed stand of both species. The effect of tree species composition on the C and N stocks and its spatial distribution was evaluated based on litterfall, root production, elevation and canopy opening, and by using a combination of modelling and geostatistical techniques. C stock was highest in the Norway spruce and the mixed stands, while N stock was highest in the mixed stand and lowest under European beech, with intermediate values in the Norway spruce stand. Each forest type showed differences in forest floor properties, suggesting that species composition is an important factor governing forest floor characteristics, including C and N stocks. The distribution of C and N stocks between forest soil layers was different for each forest type. C and N stocks were highest in the hummus layer under Norway spruce, whereas both stocks were lowest in the European beech stand. On the other hand, the mixed stand showed the highest C and N accumulation in the uppermost mineral soil layer, while the monospecific stands showed similar values. Litterfall was the main contribution to C and N stocks of the

  12. Gut microbiota composition is correlated to grid floor induced stress and behavior in the BALB/c mouse

    National Research Council Canada - National Science Library

    Bangsgaard Bendtsen, Katja Maria; Krych, Lukasz; Sørensen, Dorte Bratbo; Pang, Wanyong; Nielsen, Dennis Sandris; Josefsen, Knud; Hansen, Lars H; Sørensen, Søren J; Hansen, Axel Kornerup

    2012-01-01

    ... (Elevated Plus Maze, Light/Dark Box, and Open Field combined), the Tail Suspension Test, and Burrowing in 28 female BALB/c mice exposed to two weeks of grid floor induced stress was investigated...

  13. CFDB Steam Heat Conduction Oil Composite Boiler Application in Dyeing and Finishing Plant%循环双流化床蒸汽导热油复合锅炉在染整厂的应用

    Institute of Scientific and Technical Information of China (English)

    林金辉

    2016-01-01

    The paper discuss about the principle, structure and advantages of the one new type and high efficient boiler-CFDB steam heat conduction oil composite boiler, what's more, the boiler has the case in dyeing and finishing plant that it has been built and running. Through practical testing, it can bring certain economic benefits, environmental benefits and social benefits, and make some reference for dyeing and finishing plant boiler system integration.%本文对一种新型高效锅炉-循环双流化床蒸汽导热油复合锅炉的原理、结构及优点做了论述,且该型锅炉已在染整厂有实例建成投入运行,通过实践检验,它能够带来一定的经济效益、环保效益和社会效益,为染整厂锅炉系统整合有一定借鉴作用。

  14. Isotopic composition ([delta][sup 18]O) of the upper stalagmitic floor of Lazaret cave at Nice. Analyse de la composition isotopique ([delta][sup 18]O) du plancher stalagmitique superieur de la grotte du Lazaret a Nice

    Energy Technology Data Exchange (ETDEWEB)

    Rousseau, L.; Lumley, H. de; Bahain, J.J.; Falgueres, C. (Institut de Paleontologie, 75 - Paris (France)); Robert, F. (Museum National d' Histoire Naturelle, 75 - Paris (France))

    1994-03-17

    Radiochronological and mineralogical studies of the stalagmitic floor 'Ensemble E' of the Lazaret cave at Nice revealed that its formation has been continuous during the climatic period corresponding to 'stage 5'. In addition, biochemical analyses of this floor showed that the crystals behave as a closed system with respect to organic compounds (sterols). Oxygen isotopic compositions have registered variations which are qualitatively in agreement with those ascribed to stage 5. Therefore, these oxygen isotopic variations may be used as an independent geochemical chronometer. (authors). 15 refs.

  15. 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.

  16. 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.

  17. Trace element partitioning in ashes from boilers firing pure wood or mixtures of solid waste with respect to fuel composition, chlorine content and temperature.

    Science.gov (United States)

    Saqib, Naeem; Bäckström, Mattias

    2014-12-01

    Trace element partitioning in solid waste (household waste, industrial waste, waste wood chips and waste mixtures) incineration residues was investigated. Samples of fly ash and bottom ash were collected from six incineration facilities across Sweden including two grate fired and four fluidized bed incinerators, to have a variation in the input fuel composition (from pure biofuel to mixture of waste) and different temperature boiler conditions. As trace element concentrations in the input waste at the same facilities have already been analyzed, the present study focuses on the concentration of trace elements in the waste fuel, their distribution in the incineration residues with respect to chlorine content of waste and combustion temperature. Results indicate that Zn, Cu and Pb are dominating trace elements in the waste fuel. Highly volatile elements mercury and cadmium are mainly found in fly ash in all cases; 2/3 of lead also end up in fly ash while Zn, As and Sb show a large variation in distribution with most of them residing in the fly ash. Lithophilic elements such as copper and chromium are mainly found in bottom ash from grate fired facilities while partition mostly into fly ash from fluidized bed incinerators, especially for plants fuelled by waste wood or ordinary wood chips. There is no specific correlation between input concentration of an element in the waste fuel and fraction partitioned to fly ash. Temperature and chlorine content have significant effects on partitioning characteristics by increasing the formation and vaporization of highly volatile metal chlorides. Zinc and cadmium concentrations in fly ash increase with the incineration temperature. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Finite Element Analysis on the Deformation of Bamboo-Wood Composite Flooring%竹木复合地板变形有限元模拟

    Institute of Scientific and Technical Information of China (English)

    虞华强; 袁东; 张训亚; 费本华; 刘红征

    2011-01-01

    以表层为竹材、芯层为杉木拼板、背层为杨木单板的竹木复合地板为对象,利用ANSYS有限元软件,采用湿热类比法模拟表层和芯层厚度不同的竹木复合地板在干燥环境中的含水率变化,然后进行热结构耦合分析,研究由含水率变化引起的竹木复合地板的翘曲变形.结果表明:胶层能够起到水分屏障的作用,胶层内部木材的含水率变化很小,在使用中受空气湿度变化影响的主要是表层的竹材部分,而且表层竹材越薄的竹木复合地板其含水率越早与环境达到平衡;芯层厚度对竹木复合地板翘曲变形率有较大影响,而表层厚度对其翘曲变形率影响较小.该研究可为竹木复合地板的制造设计提供依据.%Change of moisture content in the ambient air results in non-uniform cross-section moisture profiles and generates warping deformation because of asymmetry of hygro-expansion. In order to support the design of bamboo-wood composite flooring, the moisture content(MC) changes and the deformation ratio of bamboo-wood composite flooring was investigated in dry conditions using thermal-structure coupled a-nalysis with ANSYS software. Wood and bamboo are assumed to be orthotropic materials, and adhesive layer is assumed to be homogeneous material in this model. The influence of the core layer thickness and surface layer thickness of the bamboo-wood composite flooring is taken into consideration in the model. The simulation results show that the adhesive layer between the surface and the core layer acts as a water vapor barrier because lower moisture diffusion coefficient, so the MC of the surface layer changes with the environment condition. However, the MC of the core and backing layer remains stable. The thickness of the surface has an impact on the time needed for the floor to reach the equilibrium MC and the maximum cupping deformation. Thickness of the core layer rather than the surface has great effect on the

  19. 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,...

  20. 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...

  1. Construction and design of cold-formed steel joists concrete composite floor%冷弯薄壁型钢-混凝土组合楼盖构造与设计

    Institute of Scientific and Technical Information of China (English)

    贾子文; 周绪红; 刘永健

    2013-01-01

    冷弯薄壁型钢-混凝土组合楼盖作为一种新型楼盖结构形式,需要从受力性能和构造方式方面进行更多的研究和认识.针对冷弯薄壁型钢-混凝土组合楼盖的构造特点,从基本构件、紧固件、压型钢板与楼盖梁连接、楼盖梁腹板开孔、支座加劲件、梁与柱的安装、楼盖梁布置及支撑系统等方面,对其构造进行了详细阐述.最后,提出了冷弯薄壁型钢-混凝土组合楼盖的简化模型——T形组合梁的实用计算公式,以供工程设计参考和借鉴.%The mechanical performance and construction method of cold-formed steel joists concrete composite floor,which is a new floor structure system,should be more carefully studied.According to the structural characteristics of cold-formed steel joists concrete composite floor,from basic components,fasteners,connection between profiled steel sheet and floor joists,holes on the web of floor joists,stiffeners of support saddle,installation method of beam and column,arrangement of floor joists,to bracing system and other aspects,the constructions were elaborated.Practical calculation formula of Tshaped composite beam,which is the simplified model of cold-formed steel joists concrete composite floor,was put forward,some research results were supplemented for reference in project design.

  2. 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.)

  3. 采动底板岩性及组合结构对破坏深度的制约作用%Restrictive function of lithology and its composite structure on deformation and failure depth of mining coal seam floor

    Institute of Scientific and Technical Information of China (English)

    朱术云; 曹丁涛; 周海洋; 杨朝维; 刘近国

    2014-01-01

    为了探究底板岩性及组合结构这一因素对采动底板变形破坏深度的影响,通过现场大量实测资料的整理分析,获得了类似均质底板和软硬岩不同组合结构底板在采动矿压作用下差异性变形破坏特征。研究结果表明:1)类似均质底板变形破坏规律相对简单,底板采动变形破坏深度主要受制于底板岩体的抗压破坏强度,总体上这种类型底板变形破坏程度具有自上至下呈由强及弱的渐次性变化特点;2)软硬岩夹层或互层底板采动变形破坏特征比较复杂,这种组合结构对底板采动变形破坏深度和程度均具有明显的控制作用,其中软弱夹层对底板破坏深度具有较强的约束效应,即软岩对上覆硬岩起到了重要的“褥垫效应”,对下伏岩层产生“应力扩散效应”。研究结果揭示了底板岩性及组合结构对变形破坏深度具有重要的制约作用,对巷道支护和底板水防治均具有重要的理论和实际意义。%In order to study the relationship between lithology and its composite structure and defor-mation and failure depth, based on these comprehensive field test data, restricting function of deforma-tion and failure depth to mining coal seam floor by lithology and its composite structure is discussed. The obvious difference characteristics are obtained on homogeneous floor and soft and hard rock com-posite structure floor. The study results show as follows:1) The law of deformation and failure of ho-mogeneous floor is relatively simple;the depth of deformation and failure of mining floor is controlled by the strength of floor, and has a gradual characteristics from strong to weak below floor on the whole;2) The deformation and failure floor of soft and hard rock composite structure is complex. There is an obvious restrictive function to the depth of failure floor and deformation degree by the composite structure, weak intercalation being the main

  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. Pelvic Floor Disorders

    Science.gov (United States)

    ... NICHD Research Information Clinical Trials Resources and Publications Pelvic Floor Disorders: Condition Information Skip sharing on social media links Share this: Page Content What is the pelvic floor? The term "pelvic floor" refers to the group ...

  6. Introductory guide to floors and flooring

    CSIR Research Space (South Africa)

    Billingham, PA

    1977-01-01

    Full Text Available ........................................................................ Soft floor coverings 39 Carpets ......................................................................................... 40 Laying carpets ............................................................................. 44 Wooden floors... the glue that holds the finish, causing woodwork to swell and some carpets to rot. It can carry with it dissolved salts from thesoil and thegarden and deposit theseon the floor, spoiling the finish and even flaking stonework. Water vapour can sometimes...

  7. Maxillary sinus floor elevation with a tissue-engineered bone composite of deciduous tooth stem cells and calcium phosphate cement in goats.

    Science.gov (United States)

    Zhao, Wei; Lu, Jia-Yu; Hao, Yong-Ming; Cao, Chun-Hua; Zou, De-Rong

    2017-01-01

    The study aimed to assess the effect of maxillary sinus floor elevation with tissue-engineered bone constructed from deciduous tooth stem cells (DTSCs) and calcium phosphate cement (CPC). The stem cells from goat deciduous teeth (SGDs) were isolated and transfected by means of the adenovirus with an enhanced green fluorescent protein gene (AdEGFP). As many as 18 bilateral maxillary sinuses of nine goats were randomly allocated into three groups (n = 6/group): group A (SGDs-CPC compound), group B (CPC alone) and group C (autogenous bone obtained from an iliac crest). All the samples were evaluated by computed tomography (CT), histology and histomorphometric analysis. Furthermore, the fate of implanted SGDs was traced using an immunohistochemical staining method in the decalcified samples. SGDs might be differentiated into osteoblasts in an osteogenic medium. In the present study, three-dimensional CT analysis showed that the volume of newly formed bone in group A was greater than that in the other two groups. After a healing period of 3 months, sequential analyses of triad-colour fluorescence labelling, histology and histomorphology indicated that the SGDs-CPC compound primarily promoted bone formation and mineralization at 2 and 3 months after the operation. Moreover, the areas of new bone formation in elevated sinuses were 41.82 ± 6.24% in the SGDs-CPC group, which was significantly higher than the 30.11 ± 8.05% in the CPC-alone group or the 23.07 ± 10.21% in the autogenous bone group. Immunohistochemical staining revealed that GFP and OCN were both expressed in the new bone tissue for the samples with eGFP, which suggested that the implanted SGDs might have contributed to new bone formation on the elevated sinus floor. SGDs can promote new bone formation and maturation in the goat maxillary sinus, and the tissue-engineered bone composite of SGDs and CPC might be a potential substitute for existing maxillary sinus floor elevation methods

  8. Composite materials based on poly(trimethylene carbonate) and beta-tricalcium phosphate for orbital floor and wall reconstruction

    NARCIS (Netherlands)

    van Leeuwen, Anne C.; Bos, Rudolf R. M.; Grijpma, Dirk W.

    2012-01-01

    Poly(trimethylene carbonate) and beta-tricalcium phosphate (PTMC/beta-TCP) composite materials were prepared by coprecipitation and compression molding. The effect of different amounts of the ceramic component (15 and 30 vol %) on the properties was investigated. The effect of lamination with minima

  9. Composite materials based on poly(trimethylene carbonate) and beta-tricalcium phosphate for orbital floor and wall reconstruction

    NARCIS (Netherlands)

    van Leeuwen, Anne C.; Bos, Rudolf R. M.; Grijpma, Dirk W.

    Poly(trimethylene carbonate) and beta-tricalcium phosphate (PTMC/beta-TCP) composite materials were prepared by coprecipitation and compression molding. The effect of different amounts of the ceramic component (15 and 30 vol %) on the properties was investigated. The effect of lamination with

  10. 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...

  11. 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...

  12. Optimising boiler performance.

    Science.gov (United States)

    Mayoh, Paul

    2009-01-01

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

  13. 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.

  14. Timber floors strengthened with concrete

    NARCIS (Netherlands)

    Blass, H.J.; Linden, M.L.R. van der; Schlager, M.

    1998-01-01

    Timber-concrete composite (tcc) beams may be used for the renovation of old timber floors. Although these systems are not new (Pokulka, 1997) and form a simple and practical solution, they are not widely adopted. One of the reasons for this is the Jack of uniform design rules. In this research progr

  15. Timber floors strengthened with concrete

    NARCIS (Netherlands)

    Blass, H.J.; Linden, M.L.R. van der; Schlager, M.

    1998-01-01

    Timber-concrete composite (tcc) beams may be used for the renovation of old timber floors. Although these systems are not new (Pokulka, 1997) and form a simple and practical solution, they are not widely adopted. One of the reasons for this is the Jack of uniform design rules. In this research

  16. The influence of caries disclosing agents and cavity disinfectants on microleakage of gingival floor of class V composite resin restorations

    Directory of Open Access Journals (Sweden)

    Safarcherati H

    2007-06-01

    Full Text Available Background and Aim: An important purpose of adhesive dentistry is restriction of cavity preparation to carious dentin removal and conservation of sound dentin. Application of caries disclosing agents and cavity disinfectants can help achieving this goal. The aim of this study was to evaluate the effect of caries disclosing agents and cavity disinfectants on microleakage of composite resin restorations. Materials and Methods: This experimental in-vitro study was performed on class V cavities in 48 extracted human sound premolars. The teeth were randomly divided into four equal groups. In group 1 caries detector dye (Seek, Ultradent, USA and in group 2 cavity disinfectant (Consepsis, Ultradent, USA were applied on dentinal surfaces. In group 3 both mentioned materials were applied. Group 4 was considered as control group. PQ1 bonding agent and Amelogen composite were used to restore the cavities. Gingival microleakage was assessed by dye penetration. Data were analyzed by Kruskall Wallis and Dunn tests. P<0.05 was the level of significance.Results: Group 2 showed the least and group 4 showed the highest microleakage;however no statistical significant difference was found among the groups.Conclusion: The use of caries disclosing agent (Seek and cavity disinfectant (Consepsis Liquid did not adversely affect the sealing ability of dentin bonding resins.

  17. 钢主梁拱桥组合桥面系力学性能分析%MECHANICAL BEHAVIOR ANALYSIS OF COMPOSITE DECK FLOOR OF ARCH BRIDGE WITH STEEL GIRDER

    Institute of Scientific and Technical Information of China (English)

    苏庆田; 李杰; 董冰

    2012-01-01

    钢-混凝土组合结构桥面系近几年开始在拱桥结构中使用,拱桥中组合桥面系受力复杂,其力学性能受钢与混凝土是否连接、是否张拉系杆以及混凝土的浇注顺序等影响.该文采用空间有限元模型,开展了钢主梁拱桥组合桥面系的力学性能研究.研究表明:在钢主梁拱桥结构中混凝土桥面板与钢主梁是否结合对桥面系的整体受力影响甚微,只对桥面系局部位置的混凝土桥面板应力分布有所影响;拱桥中是否安装系杆对桥面系的受力影响较大,而且桥面系的受力与系杆张拉力有密切关系;对于组合桥面系的拱桥采用一次浇筑混凝土桥面板施工方法的桥面系受力要明显优于采用分段浇筑混凝土桥面板的方法.%A steel-concrete composite deck has been used in acrh bridges recently. The mechanism of a composite deck is complex, and was affected by the factors of setting connections between concrete decks and steel girder or not, setting tied bars or not, different deck concrete casting sequences etc. In this paper, mechanical behaviors of a composite deck floor of an arch bridge with steel girders are analyzed by a spatial finite element model. The research results show that whether setting connections between concrete decks and a steel girder or not slightly affects the total mechanical behavior of a deck floor but influents the local stress of the deck; whether setting tied bar affects the deck floor mechanical property greatly and the deck floor stress depends on the tension force of tied bars heavily; as to arch bridge with a composite deck floor, the mechanical behavior of deck floors with casting deck concrete by one time is superior to that of deck floors with casting deck concrete by several times.

  18. 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

  19. Oxy-Combustion Boiler Material Development

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-01-31

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

  20. 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.

  1. 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...

  2. 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.

  3. 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.)

  4. Mixed-Up Floors.

    Science.gov (United States)

    Shaw, Richard

    2001-01-01

    Examines the maintenance management problems inherent in cleaning multiple flooring materials revealing the need for school officials to keep it simple when choosing flooring types. Also highlighted is a carpet recycling program used by Wright State University (Ohio). (GR)

  5. 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)

  6. 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.

  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. 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.

  9. 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.

  10. SUSTAINABLE TRAILER FLOORING

    Directory of Open Access Journals (Sweden)

    John Lu

    2009-05-01

    Full Text Available Different trailer flooring materials, including wood-based, aluminum, steel, and synthetic plastic floors, were evaluated in accordance with their durability and sustainability to our natural environment. Wood-based trailer flooring is an eco-friendly product. It is the most sustainable trailer flooring material compared with fossil fuel-intensive steel, aluminum, and plastics. It is renewable and recyclable. Oak, hard maple, and apitong are strong and durable hardwood species that are currently extensively used for trailer flooring. For manufacture, wood-based flooring is higher in energy efficiency and lower in carbon emission than steel, aluminum and plastics. Moreover, wood per se is a natural product that sequesters carbon. Accordingly, using more wood-based trailer flooring is effective to reduce global warming.

  11. 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...

  12. 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...

  13. 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,...

  14. 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...

  15. 双层共挤木塑复合地板的性能表征%Properties Characterization of Co-Extrusion Wood-Plastic Composite Floor with Double Layers

    Institute of Scientific and Technical Information of China (English)

    黄东辉

    2013-01-01

    Taking waste plastic,wood powder and addition agent such as antioxidant etc.as raw materials,wood-plastic composite floor with surface layer and core layer was prepared by co-extrusion technology,modification was mainly done for surface layer materials and properties of core layer materials such as weathering resistance etc wasn't considered.Physical,mechanical,low temperature resistance and weathering resistance properties of the floor were tested.The results show that tensile strength of the floor is 23.98 MPa,bending strength and bending elastic modulus are 38.53 MPa and 3 200 MPa,bending failure load is 4 300 N and higher than that of wood-plastic composite floor with single layer (3 300 N),it only declines by 1.3% after cycles of freeze-thaw test.The floor with double layers don't destroy under the drop-weight impact at low temperature,it's water absorption is 0.17%,dimensional change rate after heating is 0.12% and oxidation induction time is 77.5 min which is higher than that of wood-plastic composite floors with single layer (15.4 min),meanwhile,it achieve the requirements of wood-plastic composite floor properties test standards in Japan.The floor with double layers solves the problems that color,weathering resistance,dimension change rate,bending strength performance are fluctuation or bad because of waste recycling batch being unstable,it enlarge the application range of waste plastic and has high performance/price ratio.%以废旧塑料、木粉及抗氧剂等助剂为原料,利用共挤出的方法,制备了带有表层和芯层的木塑复合地板,主要对表层材料进行改性而不考虑芯层材料的耐候等性能,测试了该木塑复合地板的物理力学、抗低温和耐候性能.结果表明,双层共挤制备的木塑复合地板的拉伸强度为23.98 MPa,弯曲强度和弯曲弹性模量分别为38.53 MPa和3 200 MPa,弯曲破坏载荷为4300 N,高于单层挤出的木塑复合地板(3 300 N),且其经循环冻

  16. 单板复合强化木地板的研制%A study on veneer-overlaid composite laminate flooring

    Institute of Scientific and Technical Information of China (English)

    汤正捷; 徐信武

    2011-01-01

    In this paper, four-layer veneer-overlaid composite laminate floorings(VCLF) were made with wear-resistant paper, poplar veneers, 12 mm-thick high density fiberboard( HDF), and balance paper. Influences of three processing factors, i.e. , veneer thickness (1.2, 1.5, 2.0mm), adhesives ( polyurethane-PU, urea formaldehyde resin-UF) , and resin content (100,110,130,150,160 g/m2), on board properties including warping, thickness swelling (TS), inner bond strength (IB) , and machining performance, were investigated. It was found that manufacture of VCLF was technically feasible. Warping of VCLF increased with the increase of veneer thickness and resin content ( maximum value: 6% ). PU-glued VCLFs showed better performances than UF-bonded products. However, it demanded longer pressing time since PU was cured at room temperature. Recommended processing conditions were; veneer thickness 1. 2mm, PU or UF adhesive content of about 100 g/m2.%试制了“耐磨纸-意杨单板-HDF基材(12mm厚)-平衡纸”4层结构强化木地板基材,研究了单板厚度(1.2,1.5,2.0 mm)、胶黏剂种类(聚氨酯,脲醛树脂)及涂布量(单面100,110,130,150,160 g/m2)对板材翘曲度、吸水厚度膨胀率、内结合强度及机加工性能的影响.结果表明:实木贴面复合木地板具备工艺技术可行性,产品的翘曲度随单板厚度和施胶量的提高而递增(最高可达约0.6%),采用聚氨酯胶黏剂时产品性能优于脲醛树脂胶合板材,但冷压周期偏长.推荐工艺条件为:单板1.2mm,PU或UF胶黏剂均可,涂布量控制在100 g/m2左右.

  17. Human-Induced Vibration Analysis and Measurement of Long-Span Composite Floors%大跨度组合楼盖人致振动分析与实测研究

    Institute of Scientific and Technical Information of China (English)

    操礼林; 李爱群; 张志强; 周德良; 周朝阳

    2012-01-01

    In order to investigate the human-induced vibration performance of large-span composite floors, crowd excitation was simulated by the random method based on a normal footfall force curve and other individual factors such as crowd distribution and step frequency. Human-induced vibration responses of a large-span composite floor were analyzed with the help of the multi-support excitation and the time history analysis method, and multiple tuned mass dampers with different parameters were designed to control the vibration responses of the large-span floor. The actual dynamic properties of the composite floor under two distinct construction phases were tested, and vertical vibration responses of the composite floor with and without multiple tuned mass dampers under different crowd-induced excitations were measured. The research results show that the types and walking routes of human-induced excitations have significant effects on the floor responses and the large-span composite floor has very closely-spaced modes of vibration. The vertical acceleration responses induced by crowd excitation are relatively great under certain condition, and the human-induced responses of a structure with multiple tuned mass dampers decrease dramatically to meet the requirement of body serviceability.%为探讨大跨度组合楼盖的人致振动性能,基于单人脚步荷载模型,结合影响人群行走效应的因素,如人群分布、行走频率等,提出了一种人群激励的随机模拟方法.通过多点输入和时程分析法研究了某大跨度组合楼盖的人致振动反应,设计、研制了多组调谐质量阻尼器,并对该组合楼盖多个振动模态进行综合控制;实测了该大跨度组合楼盖在主体结构完成、整体结构完成2个阶段的动力特性;测试了阻尼器安装前、后组合楼盖在多种人群激励下的竖向加速度反应.研究结果表明:人群激励的类型和行走路线对楼盖振动反应影响显著;大跨度

  18. Supporting shop floor intelligence

    DEFF Research Database (Denmark)

    Carstensen, Peter; Schmidt, Kjeld; Wiil, Uffe Kock

    1999-01-01

    Many manufacturing enterprises are now trying to introduce various forms of flexible work organizations on the shop floor. However, existing computer-based production planning and control systems pose severe obstacles for autonomous working groups and other kinds of shop floor control to become r......-to-day production planning by supporting intelligent and responsible workers in their situated coordination activities on the shop floor....

  19. 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)

  20. 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.

  1. Oil ash corrosion; A review of utility boiler experience

    Energy Technology Data Exchange (ETDEWEB)

    Paul, L.D. (Babcock and Wilcox Co., Alliance, OH (United States)); Seeley, R.R. (Babcock and Wilcox Canada Ltd., Cambridge, ON (Canada))

    1991-02-01

    In this paper a review of experience with oil ash corrosion is presented along with current design practices used to avoid excessive tube wastage. Factors influencing oil ash corrosion include fuel chemistry, boiler operation, and boiler design. These factors are interdependent and determine the corrosion behavior in utility boilers. Oil ash corrosion occurs when vanadium-containing ash deposits on boiler tube surfaces become molten. These molten ash deposits dissolve protective oxides and scales causing accelerated tube wastage. Vanadium is the major fuel constituent responsible for oil ash corrosion. Vanadium reacts with sodium, sulfur, and chlorine during combustion to produce lower melting temperature ash compositions, which accelerate tube wastage. Limiting tube metal temperatures will prevent ash deposits from becoming molten, thereby avoiding the onset of oil ash corrosion. Tube metal temperatures are limited by the use of a parallel stream flow and by limiting steam outlet temperatures. Operating a boiler with low excess air has helped avoid oil ash corrosion by altering the corrosive combustion products. Air mixing and distribution are essential to the success of this palliative action. High chromium alloys and coatings form more stable protective scaled on tubing surfaces, which result in lower oil ash corrosion rates. However, there is not material totally resistant to oil ash corrosion.

  2. 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)

  3. 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.

  4. 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.

  5. Application of advanced technologies to ash-related problems in boilers

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L.L. [Sandia National Labs., Livermore, CA (United States); Richards, G.; Harb, J. [Brigham Young Univ., Provo, UT (United States). Chemical Engineering Dept.

    1995-01-01

    Prediction of ash behavior in boilers has, for many years, been based on relatively simple relationships involving the composition of inorganic material in fuels. In recent years, advanced analyses for both fuels and deposits have seen increasing use in the solid fuel combustion community. The combination of the standard and advanced analyses, together with a knowledge of boiler design and operating conditions, allow better interpretation of ash behavior in boilers than has previously been possible. This paper discusses several case histories where advanced technologies have been applied to interpret ash behavior in boilers where standard techniques were insufficient. Included in the discussion are: (1) the behavior of blends of fuels; (2) explanations for markedly different behavior between fuels with similar ASTM characteristics; and (3) effects of boiler operating conditions on ash deposit formation.

  6. The impact of co-firing sunflower husk pellets with coal in a boiler on the chemical composition of flue gas

    Directory of Open Access Journals (Sweden)

    Zajemska Monika

    2017-01-01

    The calculations showed that the most important influence on the composition of the flue gas from the co-firing process of coal with sunflower husk has a composition of biomass. It should be emphasized that the results of computer simulations obtained by the authors have an useful aspect and can be applied in practice, especially to the analysis of the mechanism of chloride corrosion which is possible to occur due to the chlorine content in the biomass. They may also be useful for evaluating the unburned hydrocarbons produced by combustion of rich mixtures (λ < 1.0.

  7. School Flooring Factors

    Science.gov (United States)

    McGrath, John

    2012-01-01

    With all of the hype that green building is receiving throughout the school facility-management industry, it's easy to overlook some elements that may not be right in front of a building manager's nose. It is helpful to examine the role floor covering plays in a green building project. Flooring is one of the most significant and important systems…

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-31

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

  9. 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.

  10. 螺旋肋筋预应力叠合板的试验研究%Experimental Research on Concrete of Prestressed Composite Floor Reinforced with Spiral Ribbed Steel Wires

    Institute of Scientific and Technical Information of China (English)

    杨万庆; 周烨

    2001-01-01

    The spiral ribbed steel wire,the newly developed product of high-strength in recent years,has the feature of high adhensive and anchorage strength..It also has good property of transmiting the prestressed.By the experiment and research on nine prestressed composite floor,this paper discusses the feasibility of demoting concrete strength grade.In this paper,the bearing property and construction techniques of the composite floor after dropping the concrete strength is another research focus.%螺旋肋钢筋是近年来开发的高强钢筋新品种,具有粘结锚固强度高、预应力传递性能好的特点。通过对9块预应力叠合板的试验研究,探讨降低混凝土强度等级的可行性及降低混凝土强度后板的受力性能和生产工艺。

  11. A Study on Manufacture and Performances of Veneer/HDF Composite Laminate Flooring%单板/HDF复合木地板的制造工艺与产品性能研究

    Institute of Scientific and Technical Information of China (English)

    徐信武; 汤正捷; 杨刚; 周坤

    2012-01-01

    Veneer/HDF composite laminate flooring (VCLF) is a new floor product in collection of advantages of both solid wood and impregnated paper overlaid laminate flooring(IPLF). Four-layer VCLF was made of wear-resisting paper, poplar veneers, 12mm-thick HDF, and balance paper. Influences of different veneer thickness, adhesive types (PU,UF), and resin contents on the flooring properties (including warping, thickness swelling, inner bond strength, and machining performance) were explored. Test results showed that:(1) manufacture of VCLF was technically feasible; (2) warping of the flooring was increased with veneer thickness and/or resin content increasing, its max value was up to about 6%; (3) PU-glued VCLFs showed better performances than UF-bonded products, while it costs longer cold pressing time. Recommended processing conditions were: veneer thickness 1.2mm, PU or UF adhesive at a content spread of about 100g/m2.%单板/高密度纤维板(HDF)复合木地板结合了实木地板和浸渍纸层压木质地板的优点,是地板产业发展的新方向之一.文中以12mm厚HDF为基材、复合意杨单板,试制了“耐磨纸-单板-HDF基材-平衡纸”四层结构地板用复合板材.研究了不同单板厚度、胶黏剂种类(聚氨酯-PU,脲醛树脂-UF)及涂布量对板材翘曲度、吸水厚度膨胀率、内结合强度及机加工性能的影响.结果表明:1)单板与HDF复合制造木地板是可行的;2)复合木地板的翘曲度随单板厚度和施胶量的提高而递增,最高可达约0.6%;3)贴面采用聚氨酯胶黏剂,产品性能优于脲醛树脂胶合板材,但冷压周期偏长.推荐工艺条件为:单板1.2mm,PU或UF胶黏剂均可,涂布量控制在100g/m2左右.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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...

  17. Task 2: Materials for Advanced Boiler and Oxy-combustion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Holcolm, Gordon R.; McGhee, Barry

    2009-05-01

    The PowerPoint presentation provides an overview of the tasks for the project: Characterize advanced boiler (oxy-fuel combustion, biomass co-fired) gas compositions and ash deposits; Generate critical data on the effects of environmental conditions; develop a unified test method with a view to future standardization; Generate critical data for coating systems for use in advanced boiler systems; Generate critical data for flue gas recycle piping materials for oxy-fuel systems; and, Compile materials performance data from laboratory and pilot plant exposures of candidate alloys for use in advanced boiler systems.

  18. 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.

  19. A Sea Floor Penetrometer.

    Science.gov (United States)

    processed through an analog-to-digital (A/D) converter, and stored in the memory of a mini-computer. Computer algorithms are applied to the deceleration data to provide real-time sea floor classification.

  20. Radiant Floor Cooling Systems

    DEFF Research Database (Denmark)

    Olesen, Bjarne W.

    2008-01-01

    In many countries, hydronic radiant floor systems are widely used for heating all types of buildings such as residential, churches, gymnasiums, hospitals, hangars, storage buildings, industrial buildings, and smaller offices. However, few systems are used for cooling.This article describes a floor...... cooling system that includes such considerations as thermal comfort of the occupants, which design parameters will influence the cooling capacity and how the system should be controlled. Examples of applications are presented....

  1. 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.

  2. 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...

  3. Effect of Thermo-treatment on Heating Dimensional Change Rate of Formed PVC Composite Wood Floor%热处理对PVC发泡复合地板加热尺寸变化率的影响

    Institute of Scientific and Technical Information of China (English)

    王洪艳; 汤文进; 徐瑞英; 方庆华; 鲍建华; 袁少飞; 李琴; 杜官本

    2014-01-01

    The formed PVC composite wood floor was treated by thermo-treatment,the heating dimensional change rate, surface morphology and thermal properties of formed PVC material treated/untreated were analyzed. The results show that the dimensional changes can be reduced evidently after the thermo-treatment because of the changes in the surface structure;the processing temperature and processing time are two important factors,the processing temperature is more significant than the processing temperature for the formed PVC composite wood floor. The dimensional changes of the formed PVC composite wood floor reduce evidently when the processing temperature is above 80℃. The rate of dimensional changes can be reduced to about 0.2%which is less than the government standard(GB/T 11982.1–2005) requirement 0.4%.%对热处理前后聚氯乙烯(PVC)发泡复合地板的加热尺寸变化率进行了研究,并对处理前后PVC发泡复合地板基材(PVC发泡材料)的表面形态及相关热性能进行了分析。结果表明,热处理后PVC复合地板基材表面泡孔结构发生明显变化,能降低复合地板的加热尺寸变化率;热处理温度和时间是两个比较重要的因素,温度较时间影响显著,温度在80℃以上对减小PVC发泡复合地板的加热尺寸变化率有明显的效果;试验中采用140℃处理1 min时, PVC发泡复合地板的加热尺寸变化率均能达到0.2%左右(低于GB/T 11982.1–2005要求的0.4%)。

  4. New Structural Wood-Bamboo Composite Panels for Container Flooring%新型结构竹木复合集装箱底板的生产技术

    Institute of Scientific and Technical Information of China (English)

    翟志忠; 陈玉和; 赵斌; 杨慧敏

    2011-01-01

    The authors used poplar, masson pine, eucalyptus veneers and bamboo curtains to produce four structural wood-bamboo composite panels for container flooring applications. The results showed that the thickness tolerance, mechanical properties, bonding strength, and impregnation stripping performance of these panels met the National Standards GB/T 19536-2004. The manufacturing costs of the new panels were reduced by 13%~21% compared with traditional container flooring products.%以价格低廉、资源丰富的人工林杨木、马尾松、桉木、竹材为原料,进行了4种不同组坯类型的竹木复合集装箱底板的试制,并检测其性能.试验证明,4种结构底板的厚度、力学性能、胶合性能和浸渍剥离性能均达到国家标准要求;且较传统组坯结构底板,生产成本降低13%~21%.

  5. 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...

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

    Science.gov (United States)

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

    2009-03-15

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

  7. [Pelvic floor and pregnancy].

    Science.gov (United States)

    Fritel, X

    2010-05-01

    Congenital factor, obesity, aging, pregnancy and childbirth are the main risk factors for female pelvic floor disorders (urinary incontinence, anal incontinence, pelvic organ prolapse, dyspareunia). Vaginal delivery may cause injury to the pudendal nerve, the anal sphincter, or the anal sphincter. However the link between these injuries and pelvic floor symptoms is not always determined and we still ignore what might be the ways of prevention. Of the many obstetrical methods proposed to prevent postpartum symptoms, episiotomy, delivery in vertical position, delayed pushing, perineal massage, warm pack, pelvic floor rehabilitation, results are disappointing or limited. Caesarean section is followed by less postnatal urinary incontinence than vaginal childbirth. However this difference tends to disappear with time and following childbirth. Limit the number of instrumental extractions and prefer the vacuum to forceps could reduce pelvic floor disorders after childbirth. Ultrasound examination of the anal sphincter after a second-degree perineal tear is useful to detect and repair infra-clinic anal sphincter lesions. Scientific data is insufficient to justify an elective cesarean section in order to avoid pelvic floor symptoms in a woman without previous disorders.

  8. Cooling Floor AC Systems

    Science.gov (United States)

    Jun, Lu; Hao, Ding; Hong, Zhang; Ce, Gao Dian

    The present HVAC equipments for the residential buildings in the Hot-summer-and-Cold-winter climate region are still at a high energy consuming level. So that the high efficiency HVAC system is an urgently need for achieving the preset government energy saving goal. With its advantage of highly sanitary, highly comfortable and uniform of temperature field, the hot-water resource floor radiation heating system has been widely accepted. This paper has put forward a new way in air-conditioning, which combines the fresh-air supply unit and such floor radiation system for the dehumidification and cooling in summer or heating in winter. By analyze its advantages and limitations, we found that this so called Cooling/ Heating Floor AC System can improve the IAQ of residential building while keep high efficiency quality. We also recommend a methodology for the HVAC system designing, which will ensure the reduction of energy cost of users.

  9. 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...

  10. 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.

  11. Thermal manipulation of the embryo modifies the physiology and body composition of broiler chickens reared in floor pens without affecting breast meat processing quality.

    Science.gov (United States)

    Loyau, T; Berri, C; Bedrani, L; Métayer-Coustard, S; Praud, C; Duclos, M J; Tesseraud, S; Rideau, N; Everaert, N; Yahav, S; Mignon-Grasteau, S; Collin, A

    2013-08-01

    Selection in broiler chickens has increased muscle mass without similar development of the cardiovascular and respiratory systems, resulting in limited ability to sustain high ambient temperatures. The aim of this study was to determine the long-lasting effects of heat manipulation of the embryo on the physiology, body temperature (Tb), growth rate and meat processing quality of broiler chickens reared in floor pens. Broiler chicken eggs were incubated in control conditions (37.8°C, 56% relative humidity; RH) or exposed to thermal manipulation (TM; 12 h/d, 39.5°C, 65% RH) from d 7 to 16 of embryogenesis. This study was planned in a pedigree design to identify possible heritable characters for further selection of broiler chickens to improve thermotolerance. Thermal manipulation did not affect hatchability but resulted in lower Tb at hatching and until d 28 post-hatch, with associated changes in plasma thyroid hormone concentrations. At d 34, chickens were exposed to a moderate heat challenge (5 h, 32°C). Greater O2 saturation and reduced CO2 partial pressure were observed (P 0.17). In conclusion, TM of the embryo modified the physiology of broilers in the long term as a possible adaptation for heat tolerance, without affecting breast meat quality. This study highlights the value of 2 new heritable characters involved in thermoregulation for further broiler selection.

  12. Manufacturing Technology of Bamboo-Fiber Based Composites Used as Container Flooring%集装箱底板用竹基纤维复合制造技术

    Institute of Scientific and Technical Information of China (English)

    余养伦; 孟凡丹; 于文吉

    2013-01-01

    The bamboo-based fiber composite container flooring was made of bamboo fibrous veneer, where a series of dotted and/or linear shaped cracks were formed on the cylinder wall of a semicircular bamboo tube so as to form a netty structural bamboo fibrous veneer which was composed of interlaced fiber bundles, using the moso bamboo and D. 0. bamboo as raw material and phenolic-formaldehyde as adhesive and then was contrasted and analyzed with traditional container flooring such as Apitong plywood, bamboo-wood composite plywood and sliver plybamboo. The results show that the physical and mechanical properties of bamboo-based fiber composites can meet or exceed the requirement of the plywood for container flooring reference to the national standard GB/T 19536-2004 without moving the outer and inner layer of bamboo through the rational structure and process design. The properties of bamboo-fiber based composites exceed that of Apitong plywood, bamboo-wood composite plywood and sliver plybamboo. The split bamboo tube is fluffed directly to make the bamboo fibrous veneer with the outer and inner layer of bamboo, which change the traditional component units structure of bamboo-based panel such as bamboo strips and bamboo sliver, so that the unavailable big-sized cluster bamboo in the existing technology can be fully used, and the process is easier, and the production efficiency is higher.%以毛竹和绿竹为原料,酚醛树脂为胶黏剂,采用点裂和线裂纤维分离技术,将半圆竹筒分离形成由竹纤维束组成的网状结构的纤维化单板,经过工艺和结构设计,制造竹基纤维复合集装箱底板,并与传统阿必通、竹木和竹篾全竹集装箱底板的性能进行对比分析.结果表明:在不去竹青和竹黄的条件下,采用合理的结构和工艺制造的竹基纤维复合材料,性能达到或超过GB/T 19536-2004《集装箱底板用胶合板》标准规定的各项指标要求,其综合性能超过传统阿必通、竹木和

  13. 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)

  14. 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)

  15. Pelvic floor muscle function in women with pelvic floor dysfunction

    DEFF Research Database (Denmark)

    Tibaek, Sigrid; Dehlendorff, Christian

    2014-01-01

    The objectives of this study were to investigate the level of pelvic floor muscle (PFM) function in women with pelvic floor dysfunction (PFD) referred by gynaecologists and urologists for in-hospital pelvic floor muscle training (PFMT), and to identity associated factors for a low level of PFM fu...

  16. 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.

  17. 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...

  18. First-time installation of a floor heating mat in a church

    Energy Technology Data Exchange (ETDEWEB)

    Hauck, E.

    Floor heating mats operate at a very low flow temperature of about 30/sup 0/C. This results in a considerable reduction of transfer losses and allows for the utilization of both renewable energy sources obtaining at a low level and waste heat. Floor heating mats need no costly and high-piling floor structure and are simply spread on to the foot fall-sound insulation. The system has been used successfully for heating a church in Belgium. The floor of the church was covered with Thermoflex heating elements consisting of PVC-coated Trevira fabric equipped with spacing fixators. The covered surface of 187 sqm was subdivided into 5 separately switchable circuits. A 30 kW low-temperature boiler was employed. The heating water with added antifreeze circulates throughout the total covered surface. Heating element costs amounted to DM 23,000, i.e. about DM 120 per sqm.

  19. Pelvic floor muscle training exercises

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003975.htm Pelvic floor muscle training exercises To use the sharing features on this page, please enable JavaScript. Pelvic floor muscle training exercises are a series of exercises ...

  20. 压型钢板-陶粒混凝土组合楼板火灾响应及火灾后受力性能试验研究%Experimental study of fire response and post-fire mechanical performance of profiled sheet-ceramsite concrete composite floor

    Institute of Scientific and Technical Information of China (English)

    王新堂; 周明; 王万祯

    2012-01-01

    In order to investigate the fire behavior of profiled sheet-ceramsite concrete composite floors ( abbreviated as PCCF) ,the fire response and structural response of two simply supported PCCF under static load were first obtained through fire experiment. Then experimental study of the post-fire mechanical performance of two composite floors after exposure to fire were carried out, and the static test of the profiled sheet-ceramsite concrete composite floor which had the same construction and dimension as the floor subjected to fire load presented here was conducted. The experimental results show that the fire-resistant ability and the post-fire bearing capacity of the composite floor can be weakened by the welding studs set in the floor. Compared with the composite floor with the same construction and dimension as the floor subjected to fire load, the failure pattern of the profiled sheet-ceramsite concrete composite floor after exposure to fire has great variation, but still has higher post-fire bearing capacity and better mechanical behavior. It is shown that the composite floor after exposure to fire exhibits the failure pattern of bending failure and the composite floor which is not subjected to fire load exhibits the failure pattern of shearing failure.%为了分析压型钢板-陶粒混凝土组合楼板的火灾响应,首先对受荷条件下的2块简支陶粒混凝土组合楼板进行了火灾行为试验,得到了其火灾温度响应及位移响应。在此基础上,进一步对2块受火后的压型钢板-陶粒混凝土组合楼板进行了火灾后受力性能试验研究,并对1块具有相同参数的组合楼板开展了常温下静载试验。结果表明:在楼板内部设置焊接栓钉将减弱组合楼板的抗火性能、降低组合楼板火灾后的承载力;与未受火作用的同样规格的组合楼板相比,火灾后压型钢板一陶粒混凝土组合楼板的破坏形式发生较大变化,但仍具有较高的承

  1. 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.

  2. 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.

  3. Quality and generation rate of solid residues in the boiler of a waste-to-energy plant

    Energy Technology Data Exchange (ETDEWEB)

    Allegrini, E., E-mail: elia@env.dtu.dk [Technical University of Denmark, Department of Environmental Engineering, Building 115, Lyngby 2800 (Denmark); Boldrin, A. [Technical University of Denmark, Department of Environmental Engineering, Building 115, Lyngby 2800 (Denmark); Jansson, S. [Umeå University, Department of Chemistry, Umeå SE-901 87 (Sweden); Lundtorp, K. [Babcock and Wilcox Vølund A/S, Göteborg (Sweden); Fruergaard Astrup, T. [Technical University of Denmark, Department of Environmental Engineering, Building 115, Lyngby 2800 (Denmark)

    2014-04-01

    Highlights: • Ash was sampled at 10 different points of the boiler of a waste-to-energy plant. • Samples were analysed for the chemical composition, PCDD/F and leaching behaviour. • Enrichment trends of elements were investigated in relation to boiler conditions. • No significant differences were found between boiler ash samples. - Abstract: The Danish waste management system relies significantly on waste-to-energy (WtE) plants. The ash produced at the energy recovery section (boiler ash) is classified as hazardous waste, and is commonly mixed with fly ash and air pollution control residues before disposal. In this study, a detailed characterization of boiler ash from a Danish grate-based mass burn type WtE was performed, to evaluate the potential for improving ash management. Samples were collected at 10 different points along the boiler's convective part, and analysed for grain size distribution, content of inorganic elements, polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD and PCDF), and leaching of metals. For all samples, PCDD and PCDF levels were below regulatory limits, while high pH values and leaching of e.g. Cl were critical. No significant differences were found between boiler ash from individual sections of the boiler, in terms of total content and leaching, indicating that separate management of individual ash fractions may not provide significant benefits.

  4. 低成本E0级实木复合地板用PUF树脂胶的研制%Research on Low Cost PUF Resin for Manufacturing E0 Grade Solid Composition Flooring

    Institute of Scientific and Technical Information of China (English)

    赵临五; 王春鹏; 张伟; 石建军; 储富祥

    2012-01-01

    按酚醛树脂的制备工艺,用NaOH为催化剂,在碱性条件下制备了U/P质量比为150%~158%的苯酚改性脲醛树脂.该胶制备工艺简单,反应平稳,操作易控制,再现性好,成本较低,贮存期达30d.该PUF胶压制的杨木三合板,桉-杨实木复合地板,胶合强度符合Ⅱ类胶合板的要求,甲醛释放量<0.5mg/L,100℃沸水煮6h浸渍剥离为0.%The phenol-urea-formaldehyde (PUF) resin for Eo degree flooring board were synthesized by alkali traditional process and using NaOH as the catalyst, with a U/P mass ratio of 150% - 158% and a F/ (P+U) mole ratio of 0.97 or 0.99. The adhesive production had many advantages of simple manufacture process, smooth reacting, easy operation and good reproducibility. The resulted PUF resins had such as low free formaldehyde, low free phenol, low cost and long reserving time(>30 days). The bond strength of PUF resin bonded composition flooring could meet the requirements of type Ⅱ plywood, the formaldehyde emission was less than 0.5mg/L, and no peeling off occurred in immersion test (PUF bonded samples immersed in l00℃ boiling water for 6hr).

  5. Ground-fire effects on the composition of dissolved and total organic matter in forest floor and soil solutions from Scots pine forests in Germany: new insights from solid state 13C NMR analysis

    Science.gov (United States)

    Näthe, Kerstin; Michalzik, Beate; Levia, Delphis; Steffens, Markus

    2016-04-01

    Fires represent an ecosystem disturbance and are recognized to seriously pertubate the nutrient budgets of forested ecosystems. While the effects of fires on chemical, biological, and physical soil properties have been intensively studied, especially in Mediterranean areas and North America, few investigations examined the effects of fire-induced alterations in the water-bound fluxes and the chemical composition of dissolved and particulate organic carbon and nitrogen (DOC, POC, DN, PN). The exclusion of the particulate organic matter fraction (0.45 μm floor (FF) and soil solutions (A, B horizon) from Scots pine forests in Germany. In relation to control sites, we test the effects of low-severity fires on: (1) the composition of DOM and TOM in forest floor and soil solutions; and (2) the translocated amount of particulate in relation to DOC and DN into the subsoil. The project aims to uncover the mechanisms of water-bound organic matter transport along an ecosystem profile and its compositional changes following a fire disturbance. Forest floor and soil solutions were fortnightly sampled from March to December 2014 on fire-manipulated and control plots in a Scots pine forest in Central Germany. Shortly after the experimental duff fire in April 2014 pooled solutions samples were taken for solid-state 13C NMR spectroscopy to characterize DOM (filtered solution < 0.8μm pore size) and TOM in unfiltered solutions. Independent from fire manipulation, the composition of TOM was generally less aromatic (aromaticity index [%] according to Hatcher et al., 1981) with values between 18 (FF) - 25% (B horizon) than the DOM fraction with 23 (FF) - 27% (B horizon). For DOM in FF solution, fire manipulation caused an increase in aromaticity from 23 to 27% compared to the control, due to an increase of the aryl-C and a decrease of the O-alkyl-C and alkyl-C signal. Fire effects were leveled out in the mineral soil. For TOM, fire effects became notable only in the A horizon

  6. 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

  7. Chronic pelvic floor dysfunction.

    Science.gov (United States)

    Hartmann, Dee; Sarton, Julie

    2014-10-01

    The successful treatment of women with vestibulodynia and its associated chronic pelvic floor dysfunctions requires interventions that address a broad field of possible pain contributors. Pelvic floor muscle hypertonicity was implicated in the mid-1990s as a trigger of major chronic vulvar pain. Painful bladder syndrome, irritable bowel syndrome, fibromyalgia, and temporomandibular jaw disorder are known common comorbidities that can cause a host of associated muscular, visceral, bony, and fascial dysfunctions. It appears that normalizing all of those disorders plays a pivotal role in reducing complaints of chronic vulvar pain and sexual dysfunction. Though the studies have yet to prove a specific protocol, physical therapists trained in pelvic dysfunction are reporting success with restoring tissue normalcy and reducing vulvar and sexual pain. A review of pelvic anatomy and common findings are presented along with suggested physical therapy management.

  8. Experimental Study of the Bending Properties and Deformation Analysis of Web-Reinforced Composite Sandwich Floor Slabs with Four Simply Supported Edges.

    Directory of Open Access Journals (Sweden)

    Yujun Qi

    Full Text Available Web-reinforced composite sandwich panels exhibit good mechanical properties in one-way bending, but few studies have investigated their flexural behavior and deformation calculation methods under conditions of four simply supported edges. This paper studies the bending performance of and deformation calculation methods for two-way web-reinforced composite sandwich panels with different web spacing and heights. Polyurethane foam, two-way orthogonal glass-fiber woven cloth and unsaturated resin were used as raw materials in this study. Vacuum infusion molding was used to prepare an ordinary composite sandwich panel and 5 web-reinforced composite sandwich panels with different spacing and web heights. The panels were subjected to two-way panel bending tests with simple support for all four edges. The mechanical properties of these sandwich panels during the elastic stage were determined by applying uniformly distributed loads. The non-linear mechanical characteristics and failure modes were obtained under centrally concentrated loading. Finally, simulations of the sandwich panels, which used the mechanical model established herein, were used to deduce the formulae for the deflection deformation for this type of sandwich panel. The experimental results show that webs can significantly improve the limit bearing capacity and flexural rigidity of sandwich panels, with smaller web spacing producing a stronger effect. When the web spacing is 75 mm, the limit bearing capacity is 4.63 times that of an ordinary sandwich panel. The deduced deflection calculation formulae provide values that agree well with the measurements (maximum error <15%. The results that are obtained herein can provide a foundation for the structural design of this type of panel.

  9. Experimental Study of the Bending Properties and Deformation Analysis of Web-Reinforced Composite Sandwich Floor Slabs with Four Simply Supported Edges.

    Science.gov (United States)

    Qi, Yujun; Fang, Hai; Liu, Weiqing

    2016-01-01

    Web-reinforced composite sandwich panels exhibit good mechanical properties in one-way bending, but few studies have investigated their flexural behavior and deformation calculation methods under conditions of four simply supported edges. This paper studies the bending performance of and deformation calculation methods for two-way web-reinforced composite sandwich panels with different web spacing and heights. Polyurethane foam, two-way orthogonal glass-fiber woven cloth and unsaturated resin were used as raw materials in this study. Vacuum infusion molding was used to prepare an ordinary composite sandwich panel and 5 web-reinforced composite sandwich panels with different spacing and web heights. The panels were subjected to two-way panel bending tests with simple support for all four edges. The mechanical properties of these sandwich panels during the elastic stage were determined by applying uniformly distributed loads. The non-linear mechanical characteristics and failure modes were obtained under centrally concentrated loading. Finally, simulations of the sandwich panels, which used the mechanical model established herein, were used to deduce the formulae for the deflection deformation for this type of sandwich panel. The experimental results show that webs can significantly improve the limit bearing capacity and flexural rigidity of sandwich panels, with smaller web spacing producing a stronger effect. When the web spacing is 75 mm, the limit bearing capacity is 4.63 times that of an ordinary sandwich panel. The deduced deflection calculation formulae provide values that agree well with the measurements (maximum error <15%). The results that are obtained herein can provide a foundation for the structural design of this type of panel.

  10. Thermal treatment and vitrification of boiler ash from a municipal solid waste incinerator.

    Science.gov (United States)

    Yang, Y; Xiao, Y; Voncken, J H L; Wilson, N

    2008-06-15

    Boiler ash generated from municipal solid waste (MSW) incinerators is usually classified as hazardous materials and requires special disposal. In the present study, the boiler ash was characterized for the chemical compositions, morphology and microstructure. The thermal chemical behavior during ash heating was investigated with thermal balance. Vitrification of the ash was conducted at a temperature of 1400 degrees C in order to generate a stable silicate slag, and the formed slag was examined with chemical and mineralogical analyses. The effect of vitrification on the leaching characteristics of various elements in the ash was evaluated with acid leaching. The study shows that the boiler ash as a heterogeneous fine powder contains mainly silicate, carbonate, sulfates, chlorides, and residues of organic materials and heavy metal compounds. At elevated temperatures, the boiler ash goes through the initial moisture removal, volatilization, decomposition, sintering, melting, and slag formation. At 1400 degrees C a thin layer of salt melt and a homogeneous glassy slag was formed. The experimental results indicate that leaching values of the vitrified slag are significantly reduced compared to the original boiler ash, and the vitrification could be an interesting alternative for a safer disposal of the boiler ash. Ash compacting, e.g., pelletizing can reduce volatilization and weight loss by about 50%, and would be a good option for the feed preparation before vitrification.

  11. 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).

  12. 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...

  13. INTRODUCTION TO INCONEL ALLOY 740: AN ALLOY DESIGNED FOR SUPERHEATER TUBING IN COAL-FIRED ULTRA SUPERCRITICAL BOILERS

    Institute of Scientific and Technical Information of China (English)

    S.J. Patel

    2005-01-01

    Chinese utilities as well as those worldwide are facingincreased demand for additional electric-ity, reduced plant emissions and greater efficiency.To meet this challenge willrequire increas-ing boiler temperature,pressure and coal ashcorrosion resistance of the materials of boiler construction of future coal-fired boilers. A new nickel-based tube alloy, INCONELRalloy 740,is described aiming at meeting this challenge. Emphasis will be on describing the alloy s mechanical properties, coal-ash and steam corrosion resistance.Microstructural stability as a function of temperature and time is addressed as well as some of the early methodology employed to arrive at the current chemical composition.

  14. Obstacles and water treatment countermeasures in boiler plant

    Energy Technology Data Exchange (ETDEWEB)

    Cho, J.R. [Hansu Co, Seoul (Korea, Republic of)

    1998-06-01

    Corrosive oxide generated at the boiler hydrosphere causes the following hindrance. Metallic oxide generated by the corrosion of steel drop and adhere to boiler and various devices to speed up secondary corrosion, and the decrease of facilities life is more promoted due to the penetration of decayed parts. Corrosive oxide generated at the boiler hydrosphere is easily accumulated and adhered to heating part and U-shaped pipe part, etc. to become scale or become scale with fixed products of hardened composition. Since corrosive oxide works as scale material to hinder heat conductivity because the heat-conduction rate of corrosive oxide is so low as 1/10 {approx} 1/50 of soft steel, it causes the damage by dropping the permitted tensile strength with the decrease of heat- conduction rate. Breakdown of facilities due to scaling of corrosive oxide happens frequently especially in high-temperature and high-pressure boiler. There are many reasons for the corrosion happening at the boiler hydrosphere such as dissolved gas, pH, temperature, dissolved salts, surface condition of metallic material, etc., but the biggest causes are dissolved gas and pH. Therefore, fundamental solution for the corrosion in boiler facilities is to get rid of dissolved gas and adjust pH. Dissolved oxygen is oxygen that is dissolved in the water, and there are mechanical and chemical methods to get rid of it. Generally, part of dissolved oxygen is first removed by mechanical method, and then leftover dissolved oxygen is removed by chemical method. The treatment of dissolved oxygen by deoxidization device is to use the principle that under same water temperature, the lower the atmospheric pressure is, the lower the solubility of oxygen becomes, and under same atmospheric pressure, the higher the water temperature is, the lower the solubility of oxygen becomes. Heating-type deoxidization and vacuum-type deoxidization are used. Chemical treatment is to use chemicals called deoxidizes to get rid of

  15. 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...

  16. 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...

  17. 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...

  18. 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.

  19. 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.

  20. [Pelvic floor muscle training and pelvic floor disorders in women].

    Science.gov (United States)

    Thubert, T; Bakker, E; Fritel, X

    2015-05-01

    Our goal is to provide an update on the results of pelvic floor rehabilitation in the treatment of urinary incontinence and genital prolapse symptoms. Pelvic floor muscle training allows a reduction of urinary incontinence symptoms. Pelvic floor muscle contractions supervised by a healthcare professional allow cure in half cases of stress urinary incontinence. Viewing this contraction through biofeedback improves outcomes, but this effect could also be due by a more intensive and prolonged program with the physiotherapist. The place of electrostimulation remains unclear. The results obtained with vaginal cones are similar to pelvic floor muscle training with or without biofeedback or electrostimulation. It is not known whether pelvic floor muscle training has an effect after one year. In case of stress urinary incontinence, supervised pelvic floor muscle training avoids surgery in half of the cases at 1-year follow-up. Pelvic floor muscle training is the first-line treatment of post-partum urinary incontinence. Its preventive effect is uncertain. Pelvic floor muscle training may reduce the symptoms associated with genital prolapse. In conclusion, pelvic floor rehabilitation supervised by a physiotherapist is an effective short-term treatment to reduce the symptoms of urinary incontinence or pelvic organ prolapse.

  1. A review on biomass as a fuel for boilers

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-06-15

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

  2. 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...

  3. 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)...

  4. 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...

  5. 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....

  6. 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...

  7. 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...

  8. 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....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-04-15

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

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

    Indian Academy of Sciences (India)

    T S Sidhu; S Prakash; R D Agrawal; Ramesh Bhagat

    2009-04-01

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

  11. 表面设置防火涂料的压型钢板混凝土组合楼板耐火性能有限元分析%The Finite Element Analysis of the Pressed Steel Concrete Composite Floor Slab Fire Performance by Setting the Fire Retardant Coating

    Institute of Scientific and Technical Information of China (English)

    段静; 麦志亨; 欧俊宏

    2014-01-01

    This article aims at the completed fire test of pr-essed steel concrete composite floor slab and uses the finite element analysis software ABQUAS to discuss the new set fire retardant coating thickness under the ISO834 standard heating environment, and analyzes the internal temperature field distri-bution influence of pressed steel concrete composite floor slab.%本文针对已完成明火试验的压型钢板混凝土组合楼板,利用ABQUAS 有限元分析软件,探讨了ISO834标准升温环境下新型防火涂料设置厚度,对压型钢板混凝土组合楼板的内部温度场分布的影响做了分析。

  12. High Temperature Corrosion in Biomass-Fired Boilers

    DEFF Research Database (Denmark)

    Henriksen, Niels; Montgomery, Melanie; Hede Larsen, Ole

    2002-01-01

    condense on superheater components. This gives rise to specific corrosion problems not previously encountered in coal-fired power plants. The type of corrosion attack can be directly ascribed to the composition of the deposit and the metal surface temperature. To avoid such high corrosion rates, woodchip...... has also been utilised as a fuel. Combustion of woodchip results in a smaller amount of ash, and potassium and chlorine are present in lesser amounts. However, significant corrosion rates were still seen. A case study of a woodchip fired boiler is described. The corrosion mechanisms in both straw...

  13. Combustion zone investigation in fuel flexible suspension fired boilers, Experimental

    DEFF Research Database (Denmark)

    Clausen, Sønnik; Fateev, Alexander; Hvid, Søren Lovmand;

    The purpose of the project is to obtain data for full-scale validation of predictive models for combustion and cocombustion of biomass in utility boilers. In addition, focus was on development of innovative optical measuring techniques as a means to increase data quality by fast measurements......-straw flame at conditions close to daily co-firing operation. 4 measurement ports was used for mapping of flames with a distance up to 6.72 m from burner wall using 5 m and 7 m long water-cooled probes. Gas temperatures and gas composition were measured by FTIR fibre-optic probe and extractive gas sampling...

  14. 浅谈锅炉微机控制技术%Boiler Computer Control Technology Introduction

    Institute of Scientific and Technical Information of China (English)

    王敏

    2001-01-01

    The composition of boiler Computer control technology is introduced herein,which is useful for saving energy,improving boiler operation level,redcing environmental pollution.%叙述了锅炉微计算机控制系统的构成。该系统能保证锅炉既可节能又可提高锅炉的运行管理水平,减轻环境污染,是一件具有意义的工作。

  15. Floor heating maximizes residents` comfort

    Energy Technology Data Exchange (ETDEWEB)

    Tirkkanen, P.; Wikstroem, T.

    1996-11-01

    Storing heat in floors by using economical night-time electricity does not increase the specific consumption of heating. According to studies done by IVO, the optimum housing comfort is achieved if the room is heated mainly by means of floor heating that is evened out by window or ceiling heating, or by a combination of all three forms of heating. (orig.)

  16. Floor heating maximizes residents` comfort

    Energy Technology Data Exchange (ETDEWEB)

    Tirkkanen, P.; Wikstroem, T.

    1996-11-01

    Storing heat in floors by using economical night-time electricity does not increase the specific consumption of heating. According to studies done by IVO, the optimum housing comfort is achieved if the room is heated mainly by means of floor heating that is evened out by window or ceiling heating, or by a combination of all three forms of heating. (orig.)

  17. Anorectal and pelvic floor anatomy

    NARCIS (Netherlands)

    J. Stoker

    2009-01-01

    The anorectum and pelvic floor are crucial in maintaining continence, facilitating evacuation, providing pelvic organ support while in females the pelvic floor is part of the birth canal. The anal sphincter is a multilayered cylindrical structure, including the smooth muscle internal sphincter and t

  18. 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.

  19. 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.

  20. 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,...

  1. 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....

  2. 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....

  3. 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

  4. Laparoscopy for pelvic floor disorders.

    Science.gov (United States)

    Van Geluwe, B; Wolthuis, A; D'Hoore, A

    2014-02-01

    Surgical treatment of pelvic floor disorders has significantly evolved during the last decade, with increasing understanding of anatomy, pathophysiology and the minimally-invasive 'revolution' of laparoscopic surgery. Laparoscopic pelvic floor repair requires a thorough knowledge of pelvic floor anatomy and its supportive components before repair of defective anatomy is possible. Several surgical procedures have been introduced and applied to treat rectal prolapse syndromes. Transabdominal procedures include a variety of rectopexies with the use of sutures or prosthesis and with or without resection of redundant sigmoid colon. Unfortunately there is lack of one generally accepted standard treatment technique. This article will focus on recent advances in the management of pelvic floor disorders affecting defecation, with a brief overview of contemporary concepts in pelvic floor anatomy and different laparoscopic treatment options.

  5. 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

  6. 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.

  7. 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.

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

    DEFF Research Database (Denmark)

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

    2017-01-01

    a significant effect under the investigated conditions. Addition of compounds which increase the melt fraction of the ash dposit, typically by forming a eutectic system, increases the adhesion strength, whereas addition of inert compounds with a high melting point decreases the adhesion strength. Furthermore......Ash deposition on boiler surfaces is a major problem encountered in biomass combustion. Timely removal of ash deposits is essentialfor optimal boiler operation. In order to improve the understanding of deposit shedding in boilers, this study investigates the adhesion strength of biomass ash from...... off by an electrically controlled arm, and the corresponding adhesion strength was measured. The effect of sintering temperature, sintering time, deposit composition, thermal shocks on the deposit, and steel type was investigated. The results reveal that the adhesion strength of ash deposits...

  9. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-01

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

  11. 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.

  12. 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.

  13. Complex Volcanism at Oppenheimer U Floor-Fractured Crater

    Science.gov (United States)

    Gaddis, L. R.; Bennett, K.; Horgan, B.; McBride, Marie; Stopar, J.; Lawrence, S.; Gustafson, J. O.; Giguere, T.

    2017-01-01

    Recent remote sensing studies have identified complex volcanism in the floor-fractured crater (FFC) Oppenheimer U, located in the northwest floor of Oppenheimer crater (35.2degS, 166.3degW, 208 km dia., Figure 1) within the "South Pole - Aitken basin" (SPA) region of the lunar far side. Up to 15 sites of pyroclastic volcanism have been identified in the floor of Oppenheimer crater. Studies of Moon Mineralogy Mapper data (M3, 0.4-3 microns, 86 bands, [5]) indicated that the pyroclastic deposits are comprised of mixtures of clinopyroxene and iron-rich glass, with the Oppenheimer U deposit showing variable composition within the FFC and having the most iron-rich volcanic glass thus far identified on the Moon. Here we examine the floor of Oppenheimer U in more detail and show evidence for possible multiple eruptive vents.

  14. Crustal Ages of the Ocean Floor - Poster

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Crustal Ages of the Ocean Floor Poster was created at NGDC using the Crustal Ages of the Ocean Floor database draped digitally over a relief of the ocean floor...

  15. Co-Combustion of Animal Waste in a Commercial Waste-to-Energy BFB Boiler

    Directory of Open Access Journals (Sweden)

    Farzad Moradian

    2013-11-01

    Full Text Available Co-combustion of animal waste, in waste-to-energy boilers, is considered a method to produce both heat and power and to dispose of possibly infected animal wastes. This research conducted full-scale combustion tests to identify the impact of changed fuel composition on a fluidized-bed boiler. The impact was characterized by analyzing the deposit formation rate, deposit composition, ash composition, and emissions. Two combustion tests, denoted the reference case and animal waste case, were performed based on different fuel mixes. In the reference case, a normal solid waste fuel mix was combusted in the boiler, containing sorted industry and household waste. In the animal waste case, 20 wt% animal waste was added to the reference fuel mix. The collected samples, comprising sampling probe deposits, fuel mixes, bed ash, return sand, boiler ash, cyclone ash and filter ash, were analyzed using chemical fractionation, SEM-EDX and XRD. The results indicate decreased deposit formation due to animal waste co-combustion. SEM-EDX and chemical fractionation identified higher concentrations of P, Ca, S, and Cl in the bed materials in the animal waste case. Moreover, the risk of bed agglomeration was lower in the animal waste case and also a decreased rate of NOx and SO2 emissions were observed.

  16. Flooring choices for newborn ICUs.

    Science.gov (United States)

    White, R D

    2007-12-01

    Floors are a major element of newborn intensive care unit (NICU) construction. They provide visual cues, sound control, and with certain materials, some degree of physical comfort for workers. Flooring materials may entail a significant cost for installation and upkeep and can have substantial ecological impact, both in the choice of the flooring itself, as well as the substances used to clean it. In this article the important aspects to consider for each factor are explored and recommendations are offered for appropriate choices in various NICU areas.

  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. 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.).

  19. 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

  20. 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.

  1. Channel Floor Yardangs

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Released 19 July 2004 The atmosphere of Mars is a dynamic system. Water-ice clouds, fog, and hazes can make imaging the surface from space difficult. Dust storms can grow from local disturbances to global sizes, through which imaging is impossible. Seasonal temperature changes are the usual drivers in cloud and dust storm development and growth. Eons of atmospheric dust storm activity has left its mark on the surface of Mars. Dust carried aloft by the wind has settled out on every available surface; sand dunes have been created and moved by centuries of wind; and the effect of continual sand-blasting has modified many regions of Mars, creating yardangs and other unusual surface forms. The yardangs in this image are forming in channel floor deposits. The channel itself is funneling the wind to cause the erosion. Image information: VIS instrument. Latitude 4.5, Longitude 229.7 East (133.3 West). 19 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from

  2. The shop floor scheduling game

    NARCIS (Netherlands)

    Riezebos, Jan; Slomp, Jannes

    1995-01-01

    The aim of the shop floor scheduling game is getting participants acquainted with: - developing robust planning and scheduling procedures; - accepting orders under uncertainty and competition; - using information from cost accounting in scheduling; - creating an adequate communication structure

  3. Functional anatomy of pelvic floor

    OpenAIRE

    Salvatore Rocca Rossetti

    2016-01-01

    Generally, descriptions of the pelvic floor are discordant, since its complex structures and the complexity of pathological disorders of such structures; commonly the descriptions are sectorial, concerning muscles, fascial developments, ligaments and so on. On the contrary to understand completely nature and function of the pelvic floor it is necessary to study it in the most unitary view and in the most global aspect, considering embriology, philogenesy, anthropologic development and its mul...

  4. 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.

  5. Boiler house modernization through shared savings program

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-31

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

  6. 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. 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.

  9. 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 ...

  10. The partitioning of calcium and sulfur between bottom ash and flyash in a commercial CFB boiler

    Energy Technology Data Exchange (ETDEWEB)

    Rozelle, P.L.; Pisupati, S.V.; Morrison, J.L.; Scaroni, A.W.

    1999-07-01

    As part of a program to examine the effect of sorbent properties on sulfation performance in the circulating fluidized bed (CFB) combustion process, a series of sorbents varying in chemical composition was tested under similar operating conditions in a 30 MW(e) CFB boiler. These sorbents ranged from 27.8 to 55.2 wt% CaO, and from 0.54 to 18.8 wt% MgO. The fuel used was a high ash content (68 wt%) coal refuse. Parameters of boiler operation were established from distributed control system data, used to screen test results, and data were eliminated from consideration where changes in boiler load or bed inventory levels were seen prior to sampling of bottom ash and flyash streams. This, and the development of a set of simultaneous equations for measuring individual ash stream flow rates, allowed the computation of calcium and sulfur material balances around the boiler for each sorbent test. The partitioning of calcium and sulfur to the bottom ash and flyash streams was examined. It was found that the majority of both calcium and sulfur fed to the boiler was removed with the flyash, regardless of the sorbent. It was further found that across the range of sorbent properties, the flow of sulfur as a solid with the flyash was relatively uniform (71 to 86 wt% of that fed to the boiler). Calcium to sulfur ratios in the bottom ash were uniformly higher than those found for the corresponding flyash streams, indicating that attrition may play a key role in overall sorbent performance. The calcium balance data also indicated that thermally induced fractures (TIFs) may affect attrition.

  11. Tangential Floor in a Classroom Setting

    Science.gov (United States)

    Marti, Leyla

    2012-01-01

    This article examines floor management in two classroom sessions: a task-oriented computer lesson and a literature lesson. Recordings made in the computer lesson show the organization of floor when a task is given to students. Temporary or "incipient" side floors (Jones and Thornborrow, 2004) emerge beside the main floor. In the literature lesson,…

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. Evaluation of thermal overload in boiler operators.

    Science.gov (United States)

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

    2012-01-01

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

  17. Direct contact, binary fluid geothermal boiler

    Science.gov (United States)

    Rapier, Pascal M.

    1982-01-01

    Energy is extracted from geothermal brines by direct contact with a working fluid such as isobutane which is immiscible with the brine in a geothermal boiler. The geothermal boiler provides a distributor arrangement which efficiently contacts geothermal brine with the isobutane in order to prevent the entrainment of geothermal brine in the isobutane vapor which is directed to a turbine. Accordingly the problem of brine carry-over through the turbine causes corrosion and scaling thereof is eliminated. Additionally the heat exchanger includes straightening vanes for preventing startup and other temporary fluctuations in the transitional zone of the boiler from causing brine carryover into the turbine. Also a screen is provided in the heat exchanger to coalesce the working fluid and to assist in defining the location of the transitional zone where the geothermal brine and the isobutane are initially mixed.

  18. 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...

  19. THERMAL BOUNDARY LAYER IN CFB BOILER RISER

    Institute of Scientific and Technical Information of China (English)

    Jinwei; Wang; Xinmu; Zhao; Yu; Wang; Xing; Xing; Jiansheng; Zhang; Guangxi; Yue

    2006-01-01

    Measurement of temperature profiles of gas-solid two-phase flow at different heights in commercial-scale circulating fluidized bed (CFB) boilers was carried out. Experimental results showed that the thickness of thermal boundary layer was generally independent of the distance from the air distributor, except when close to the riser outlet. Through analysis of flow and combustion characteristics in the riser, it was found that the main reasons for the phenomena were: 1) the hydrodynamic boundary layer was thinner than the thermal layer and hardly changed along the CFB boiler height, and 2) both radial and axial mass and heat exchanges were strong in the CFB boiler. Numerical simulation of gas flow in the outlet zone confirmed that the distribution of the thermal boundary layer was dominated by the flow field characteristics.

  20. On the influence of chlorides and sulphureous compounds on the corrosion of superheater tubes in boilers with special consideration on kraft recovery boilers

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Fredrik [AaF-IPK AB, Stockholm (Sweden)

    1999-03-01

    This report reviews the thermochemistry of the most relevant corrosion reactions and mechanisms with chloride especially considering the kraft pulp mill recovery boiler. The flue gas side corrosion of superheater tubes is governed by the fuel constituents, and by the carryover particles and the gaseous impurities accompanying the flue gases and the local chemical conditions they cause on the superheater tube surface. A study made on coal-fired boilers in Germany has been interpreted so that the protective ability of the oxide layer on the tube surface of a superheater tube is limited, which causes a close to linear time dependence of the material loss due to corrosion. The thermochemistry of the reactions of the protective oxide layer itself with the components of the deposited carryover and the flue gas sulphur components seems thus to govern the mechanism of the corrosion. The corrosion in the recovery boiler is concluded to be more dependant on this combined action of carry-over and sulphureous oxides, so the presence of chlorides in the flue gases only influences the melting range properties of the sulphate deposits, but seems to exert less influence on the chemical reactions which attack the oxides of the passive layer. The thermochemistry also explains the formation of a sulphide layer often found between the deposits and the surface of the tube metal on superheater tubes as a result of reaction with sulpureous oxides from the flue gas and carbon in the carryover. The factors which in practice limit the superheater corrosion in the recovery boiler are interpreted as both material and process dependent. The main limiting factor for the steam temperature is still the melting range of the sulphate deposit. There seems thus to be little hope for the aim to raise the steam temperature of the kraft recovery boiler above the range which is already achievable with the presently available composite tubes 22 refs, 10 figs

  1. 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.

  2. Planning Annual Shutdown Inspection for BFB Boiler

    OpenAIRE

    Sorsa, Tatu

    2014-01-01

    The goal of this thesis was to create an illustrative guidebook of annual inspection planning for BFB boiler to help power plant operator when planning of annual inspection is topical. This thesis was made for Andritz Oy and it is based on inspection reports and experiences of BFB boiler’s maintenance and inspection staff. In this thesis it is shown how to plan an annual inspection for BFB boiler and thesis gives good tools and hints for operator to manage inspection from the beginning ...

  3. Boiler derating for coal-water mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Horney, F.A.; Nolte, F.S.

    1983-11-01

    The authors demonstrated a method for approximating the derating required when converting an oil or natural gas fired unit to a coal-water mixture. If the results show that a retrofit to coal-water mixture appears economically reasonable, then a more detailed analysis should be made by the boiler manufacturer whose methods are more precise than the methods of this paper. The expense of having the boiler manufacturer make a precise analysis can be avoided if the results of the analysis of this paper show conversion not to be viable.

  4. 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.

  5. 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...

  6. MSWI boiler fly ashes: magnetic separation for material recovery.

    Science.gov (United States)

    De Boom, Aurore; Degrez, Marc; Hubaux, Paul; Lucion, Christian

    2011-07-01

    Nowadays, ferrous materials are usually recovered from Municipal Solid Waste Incineration (MSWI) bottom ash by magnetic separation. To our knowledge, such a physical technique has not been applied so far to other MSWI residues. This study focuses thus on the applicability of magnetic separation on boiler fly ashes (BFA). Different types of magnet are used to extract the magnetic particles. We investigate the magnetic particle composition, as well as their leaching behaviour (EN 12457-1 leaching test). The magnetic particles present higher Cr, Fe, Mn and Ni concentration than the non-magnetic (NM) fraction. Magnetic separation does not improve the leachability of the NM fraction. To approximate industrial conditions, magnetic separation is also applied to BFA mixed with water by using a pilot. BFA magnetic separation is economically evaluated. This study globally shows that it is possible to extract some magnetic particles from MSWI boiler fly ashes. However, the magnetic particles only represent from 23 to 120 g/kg of the BFA and, though they are enriched in Fe, are composed of similar elements to the raw ashes. The industrial application of magnetic separation would only be profitable if large amounts of ashes were treated (more than 15 kt/y), and the process should be ideally completed by other recovery methods or advanced treatments.

  7. Functional anatomy of pelvic floor

    Directory of Open Access Journals (Sweden)

    Salvatore Rocca Rossetti

    2016-03-01

    Full Text Available Generally, descriptions of the pelvic floor are discordant, since its complex structures and the complexity of pathological disorders of such structures; commonly the descriptions are sectorial, concerning muscles, fascial developments, ligaments and so on. On the contrary to understand completely nature and function of the pelvic floor it is necessary to study it in the most unitary view and in the most global aspect, considering embriology, philogenesy, anthropologic development and its multiple activities others than urological, gynaecological and intestinal ones. Recent acquirements succeeded in clarifying many aspects of pelvic floor activity, whose musculature has been investigated through electromyography, sonography, magnetic resonance, histology, histochemistry, molecular research. Utilizing recent research concerning not only urinary and gynecologic aspects but also those regarding statics and dynamics of pelvis and its floor, it is now possible to study this important body part as a unit; that means to consider it in the whole body economy to which maintaining upright position, walking and behavior or physical conduct do not share less than urinary, genital, and intestinal functions. It is today possible to consider the pelvic floor as a musclefascial unit with synergic and antagonistic activity of muscular bundles, among them more or less interlaced, with multiple functions and not only the function of pelvic cup closure.

  8. Functional anatomy of pelvic floor.

    Science.gov (United States)

    Rocca Rossetti, Salvatore

    2016-03-31

    Generally, descriptions of the pelvic floor are discordant, since its complex structures and the complexity of pathological disorders of such structures; commonly the descriptions are sectorial, concerning muscles, fascial developments, ligaments and so on. On the contrary to understand completely nature and function of the pelvic floor it is necessary to study it in the most unitary view and in the most global aspect, considering embriology, philogenesy, anthropologic development and its multiple activities others than urological, gynaecological and intestinal ones. Recent acquirements succeeded in clarifying many aspects of pelvic floor activity, whose musculature has been investigated through electromyography, sonography, magnetic resonance, histology, histochemistry, molecular research. Utilizing recent research concerning not only urinary and gynecologic aspects but also those regarding statics and dynamics of pelvis and its floor, it is now possible to study this important body part as a unit; that means to consider it in the whole body economy to which maintaining upright position, walking and behavior or physical conduct do not share less than urinary, genital, and intestinal functions. It is today possible to consider the pelvic floor as a musclefascial unit with synergic and antagonistic activity of muscular bundles, among them more or less interlaced, with multiple functions and not only the function of pelvic cup closure.

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

    Directory of Open Access Journals (Sweden)

    Hongchao Wang

    2012-12-01

    Full Text Available 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 system has convenience to use, high reliability, which play an active role to improve the operating efficiency, to prevent the boiler accident, and to decrease the energy consumption.

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

    Directory of Open Access Journals (Sweden)

    B. A. Bayrashevsky

    2009-01-01

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

  11. Debugging and Rectification of Electric Heating Boilers

    Institute of Scientific and Technical Information of China (English)

    GE; Cheng-song

    2015-01-01

    Steam system of CRARL mainly provides steam for dissolving system,and steam was transported through pipes.The major equipment is a150kW steam electric heating boiler(FH-JZ-003),with rated evaporation 0.2T/h and rated pressure 1.0MPa.It was found during debugging

  12. Is That Boiler Ready To Blow?

    Science.gov (United States)

    Robinson, Glenn S.; Trombley, Robert E.

    2001-01-01

    Discusses implementation of a thorough assessment program to determine the condition of boilers, pressure vessels and other plant equipment to determine the feasibility of part or entire system replacement. Assessment basics are examined as are tips for selecting the right inspection and engineering contractor for assessments. (GR)

  13. 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.

  14. Environmental control during steam boiler washing

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-12-31

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

  15. 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...

  16. Detecting Astrobiologically Significant Ocean Floor Sediments in the Tsunami-Battered Coasts of Early Mars

    Science.gov (United States)

    Rodriguez, J. A. P.; Zarroca, M.; Linares, R.; Komatsu, G.; Oehler, D.; Davila, A.; Baker, V.; Bernman, D.; Miyamoto, H.

    2017-10-01

    We document a potential tsunami deposit that was emplaced over a possible early Mars coastal cape. Unlike other deposits proposed to have been due to tsunamis extending far inland, its composition may be dominated by displaced ocean floor materials.

  17. Temperature Distribution of Biodiesel Blends Combustion in Boiler using CFD-Fluent

    Directory of Open Access Journals (Sweden)

    Lia Cundari

    2016-02-01

    Full Text Available The use of biodiesel have been tested on some combustion devices extensively, including on the boiler. Biodiesel blends use in boiler is possibly affected the behaviour of combustion. It can be evaluated by analysing the exhaust gas composition and temperature. This study is conducted to show the distribution of temperature in the combustion chamber and boiler stack’s using Computational Fluid Dynamic (CFD software Fluent. Experimentally, the tests carried out on the fire tube boiler vertical type cylinder with pressure of 3 bar. Temperature measurement is performed at three points in the combustion chamber and boilers’ stack using optional thermocouple and gas analyzer IMR 1400. The biodiesel used in the tests is palm oil based with blending portion varies from 5-25%. The results show that in the higher blend of biodiesel, the temperature of combustion chamber tend to be lower but the exhaust gas temperature at the end of the chimney was likely to increase. On the other hand, the simulation using FLUENT showed the pattern of temperature distribution was relatively equal between the use of biodiesel in the blends under 25% compared to the use of diesel (B0.

  18. Branding on the Shop Floor

    DEFF Research Database (Denmark)

    Gyimóthy, Szilvia; Jonas, Louise Rygaard

    2010-01-01

    , a Danish supermarket chain. During the implementation of the “Best Butcher in Town”-project, Kvickly’s shop floor becomes an engineered servicescape where the norms of good salesmanship must be performed. By documenting the disloyal behaviour of butchers, we demonstrate that the affective commitment...

  19. Low Cost Polymer heat Exchangers for Condensing Boilers

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-09-30

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

  20. Guide to Low-Emission Boiler and Combustion Equipment Selection

    Energy Technology Data Exchange (ETDEWEB)

    Oland, CB

    2002-05-06

    Boiler owners and operators who need additional generating capacity face a number of legal, political, environmental, economic, and technical challenges. Their key to success requires selection of an adequately sized low-emission boiler and combustion equipment that can be operated in compliance with emission standards established by state and federal regulatory agencies. Recognizing that many issues are involved in making informed selection decisions, the U.S. Department of Energy (DOE), Office of Industrial Technologies (OIT) sponsored efforts at the Oak Ridge National Laboratory (ORNL) to develop a guide for use in choosing low-emission boilers and combustion equipment. To ensure that the guide covers a broad range of technical and regulatory issues of particular interest to the commercial boiler industry, the guide was developed in cooperation with the American Boiler Manufacturers Association (ABMA), the Council of Industrial Boiler Owners (CIBO), and the U.S. Environmental Protection Agency (EPA). The guide presents topics pertaining to industrial, commercial, and institutional (ICI) boilers. Background information about various types of commercially available boilers is provided along with discussions about the fuels that they burn and the emissions that they produce. Also included are discussions about emissions standards and compliance issues, technical details related to emissions control techniques, and other important selection considerations. Although information in the guide is primarily applicable to new ICI boilers, it may also apply to existing boiler installations.

  1. Raise the Floor When Remodeling Science Labs

    Science.gov (United States)

    Nation's Schools, 1972

    1972-01-01

    A new remodeling idea adopts the concept of raised floor covering gas, water, electrical, and drain lines. The accessible floor has removable panels set into an adjustable support frame 24 inches above a concrete subfloor. (Author)

  2. How Are Pelvic Floor Disorders Commonly Treated?

    Science.gov (United States)

    ... Information Clinical Trials Resources and Publications How are pelvic floor disorders commonly treated? Skip sharing on social media ... Treatment Nonsurgical treatments commonly used for PFDs include: Pelvic floor muscle training (PFMT). Also called Kegel (pronounced KEY- ...

  3. How Are Pelvic Floor Disorders Diagnosed?

    Science.gov (United States)

    ... Information Clinical Trials Resources and Publications How are pelvic floor disorders diagnosed? Skip sharing on social media links ... fee ). This test is used to evaluate the pelvic floor and rectum while the patient is having a ...

  4. The Characterization of Twin-Wire Arc-Sprayed FeCrBSi Coating and the Application in Sewage Sludge Boilers

    Science.gov (United States)

    Qin, Enwei; Huang, Qian; Shao, Yumin; Chen, Guoxing; Ye, Lin; Gu, Qin; Wu, Shuhui

    2014-12-01

    Incineration in boilers is an environment-friendly treatment for industrial and civil sewage sludge. However, due to the aggressive nature of the sludge, the boiler fireside-surface is subjected to severe wear, erosive, and high temperature corrosion problems during incineration. In this study, we developed an economical FeCrBSi wire material with iron weight content as high as 80%. The coating was prepared by twin-wire arc spraying processing. The chemical compositions of the coating, as well as phase components were analyzed by energy-dispersive spectroscopy and x-ray diffraction method. The surface roughness, porosity, and cross-sectional morphology were further characterized. The coating hardness is close to that of the commercial Armacor M and Armacor C materials. In-boiler test was also carried out. The low thickness loss of the tube indicates a promising application future in sludge boilers.

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

    Science.gov (United States)

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

    2015-03-01

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

  6. 7 CFR 2902.39 - Floor strippers.

    Science.gov (United States)

    2010-01-01

    ... Floor strippers. (a) Definition. Products that are formulated to loosen waxes, resins, or varnishes from floor surfaces. They can be in either liquid or gel form, and may also be used with or without... 7 Agriculture 15 2010-01-01 2010-01-01 false Floor strippers. 2902.39 Section 2902.39...

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

    Energy Technology Data Exchange (ETDEWEB)

    Kung, Steven; Rapp, Robert

    2014-08-31

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

  8. 装配式钢结构新型轻质叠合楼板设计研究%DESIGH STUDY OF THE NEW LIGHT-WEIGHT COMPOSITE FLOOR OF THE PREFABRICATED STEEL STRUCTURE

    Institute of Scientific and Technical Information of China (English)

    张爱林; 赵越; 刘学春

    2014-01-01

    在新型钢筋桁架发泡水泥夹芯叠合楼板中应用新型材料发泡水泥,能够实现楼板构件更轻、高效保温,且隔热隔声功能也优于钢筋桁架混凝土楼板。利用换算惯性矩方法对叠合楼板在施工阶段的短期刚度进行研究,得到发泡水泥夹芯叠合楼板的短期刚度计算公式,并通过算例对比研究发泡水泥预制层对楼板截面刚度的贡献作用。结果表明,发泡水泥预制层对截面刚度贡献很小,只占总刚度的10%左右,这主要是由于发泡水泥强度小、弹性模量小,所以在实际简化计算分析时,可不考虑发泡水泥预制层的作用。%A new style floor slab by steel truss and foam cement is introduced in this paper .Due to the use of the new light-weight material foam cement , the floor slab has advantage over the traditional steel truss slab with concrete in further light-weight, thermal and sound insulation properties .In this paper, the short-term stiffness of the floor during the construction phase was studied by the effective moment of inertia method , and a formula was presented .The contribution of precast foam cement layer to the stiffness of the floor cross-section was analysed by an example .The result shows that the contribution of the foam cement layer is a small part of 10%, mainly due to the low strength and small elasticity modulus of the foam cement .Therefore, to simplify the calculation and analysis , the role of prefabricated foam cement layer can be ignored .

  9. Maximising safety in the boiler house.

    Science.gov (United States)

    Derry, Carr

    2013-03-01

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

  10. Life extension of boilers using weld overlay protection

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-12-31

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

  11. R&D and Demonstration of Large Domestic CFB Boilers

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ In order to develop large CFB boilers with independent intellectual property,Xi'an Thermal Power Research Institute (TPRI) established a laboratory with complete functions for the technical development of CFB boilers.This laboratory consists ofa 1-MW and a 4-MW CFB combustion test facilities and a laboratory for limestone desulphurization performance evaluation.It carried out tests on CFB combustion and desulphurization for Chinese typical coals and limestone and research on heat-transfer characteristics and key parts,and developed the first home-made 100-MW CFB boiler.Based on the experience of R&D,the laboratory further researched key techniques for enlarging capacity systematically,and cooperating with Harbin Boiler Co.(HBC),developed the first domestic 210-MW CFB boiler with independent intellectual property and put it into engineering demonstration,laying a solid foundation for the development of CFB boilers of even larger capacity.

  12. 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.

  13. Field Test of Boiler Primary Loop Temperature Controller

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-09-01

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

  14. TRIO specification of a steam boiler controller

    Energy Technology Data Exchange (ETDEWEB)

    Gargantini, A. [Politecnico di Milano (Italy). Dipt. di Electronica e Informazione; Morzenti, A. [Politecnico di Milano (Italy). Dipt. di Electronica e Informazione

    1996-12-31

    We specify a controller for a steam boiler starting from an informal descriptions of its requirements. The specification is formalized in the temporal logic TRIO and its object-oriented extension TRIO+. To obtain a maximum of abstraction and reuse we make the specification parametric with respect to all equipment and hardware features, and we avoid to impose any particular strategy in the management of the available resources and in the control of the critical physical quantities. (orig.)

  15. Circulating fluidized bed boilers design and operations

    CERN Document Server

    Basu, Prabir

    1991-01-01

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

  16. Obesity and pelvic floor dysfunction.

    Science.gov (United States)

    Ramalingam, Kalaivani; Monga, Ash

    2015-05-01

    Obesity is associated with a high prevalence of pelvic floor disorders. Patients with obesity present with a range of urinary, bowel and sexual dysfunction problems as well as uterovaginal prolapse. Urinary incontinence, faecal incontinence and sexual dysfunction are more prevalent in patients with obesity. Uterovaginal prolapse is also more common than in the non-obese population. Weight loss by surgical and non-surgical methods plays a major role in the improvement of these symptoms in such patients. The treatment of symptoms leads to an improvement in their quality of life. However, surgical treatment of these symptoms may be accompanied by an increased risk of complications in obese patients. A better understanding of the mechanism of obesity-associated pelvic floor dysfunction is essential.

  17. [Surgical dilemmas. Sinus floor elevation].

    Science.gov (United States)

    ten Bruggenkate, C M; Schulten, E A J M; Zijderveld, S A

    2008-12-01

    Limited alveolar bone height prevents the placement of dental implants. Sinus floor elevation is an internal augmentation of the maxillary sinus that allows implants to be placed. The principle of this surgical procedure is the preparation of a 'top hinge door', that is raised together with the Schneiderian membrane in the cranial direction. The space which created under this lid is filled with a bone transplant. Autogenous bone is the standard transplant material, despite the fact that a second surgery site is necessary. Under certain circumstances bone substitutes can be used, with a longer healing phase. If sufficient alveolar bone height is available to secure implant stability, simultaneous implantation and sinus floor elevation are possible. Considering the significant anatomical variation in the region of the maxillary sinus, a sound knowledge of the anatomy is of great importance.

  18. Branding on the Shop Floor

    OpenAIRE

    Szilvia Gyimóthy; Louise Rygaard Jonas

    2010-01-01

    Service branding is a particular form of emotional management, where employees are regarded as adaptable media, who can be trained to convey corporate values while interacting with customers. This paper examines the identity work of butchers during the brand revitalisation campaign of Kvickly, a Danish supermarket chain. During the implementation of the “Best Butcher in Town”-project, Kvickly’s shop floor becomes an engineered servicescape where the norms of good salesmanship must be performe...

  19. Computer monitoring and optimization of the steam boiler performance

    OpenAIRE

    Sobota Tomasz

    2017-01-01

    The paper presents a method for determination of thermo-flow parameters for steam boilers. This method allows to perform the calculations of the boiler furnace chamber and heat flow rates absorbed by superheater stages. These parameters are important for monitoring the performance of the power unit. Knowledge of these parameters allows determining the degree of the furnace chamber slagging. The calculation can be performed in online mode and use to monitoring of steam boiler. The presented me...

  20. 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.

  1. Particulate emission abatement for Krakow boiler houses

    Energy Technology Data Exchange (ETDEWEB)

    Wysk, R.

    1995-12-31

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

  2. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-10-20

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

  3. Deposit trends in biomass fired boilers. A study in multivariable data analysis; Avlagringstrender i pannor eldade med biobraensle. En studie utfoerd med multivariat dataanalys

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Mattias

    2003-05-01

    Many different studies have been made on deposit formation in bio-fuel fired boilers. Usually those studies are carried out with univariate analysis, which means the correlation between variables is examined by changing one variable at a time. In this report multivariable analysis is used to try and get a wider perspective of the correlation structures between variables. This report gives an introduction to how multivariable data analysis (MVDA) can be used to find trends in SEM-EDX (scanning electron microscope with energy dispersive X-ray spectroscopy) analyzed deposit probes, and will also give a summary of the problems that are induced by deposit formation (foremost corrosion and thermal conductivity depletion). The uses of MVDA will be explored by analysing examples from three different studies and boilers. First a grate boiler with different fuels, then a 131713-boiler (bubbling fluidised bed) with different fuels and operational parameters and at last three different boilers (one 13F13 and two CF13-boilers, circulating fluidised bed) with similar fuels. The results from the MVDA-analyse showed that: The greatest differences in the chemical compositions of the deposit samples dealt with in the report were found in the molar contents of calcium, oxygen, potassium and sulphur. Other elements showed much smaller variations. Trends and groupings were therefore mainly observed in these elements. There was a clear correlation between potassium and sulphur in all examples, which probably means potassium chloride reacts with sulphur dioxide to form potassium sulphate. Deposit composition could be used to explain the total weight gain of test rings. Only observations from one of the ring sides were used (windward- or leeward), because deposit composition often differed between the these two sides. CFB-boilers behaved differently from grate- and BFB-boilers when the molar compositions of deposits from different ring sides were compared. The CFB-boilers showed

  4. Linear Alkylbenzenesulfonates in indoor Floor Dust

    DEFF Research Database (Denmark)

    Wolkoff, Peder; Madsen, Jørgen Øgaard

    1999-01-01

    The amount of Linear Alkylbenzenesulfonates (LAS) in the particle fraction of floor dust sampled from 7 selected public buildings varied between 34 and 1500 microgram per gram dust, while the contents of the fibre fractions generally were higher with up to 3500 microgram LAS/g dust. The use...... of a cleaning agent with LAS resulted in an increase of the amount of LAS in the floor dust after floor wash relative to just before floor wash. However, the most important source of LAS in the indoor floor dust appears to be residues of detergent in clothing. Thus, a newly washed shirt contained 2960 microgram...

  5. Field Test of Boiler Primary Loop Temperature Controller

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-09-01

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

  6. Mechanical properties of refractory concretes for boilers; Propriedades mecanicas de concretos refratarios para caldeiras

    Energy Technology Data Exchange (ETDEWEB)

    Angioletto, E.; Pelisser, F.; Peterson, M.; Angioletto, E.; Rocha, M.R.; Arnt, A.B.C. [Universidade do Estado de Santa Catarina (UDESC), Criciuma, SC (Brazil)], E-mail: ean@unesc.net; Coelho, R. [Tractebel Energia, Florianpolis, SC (Brazil)

    2010-07-01

    Refractory concretes are used in extremely physically demanding conditions. An important example is concretes used as sealing systems in boilers, where their dimensional stability at high temperatures is fundamental to durability and has a strong impact on maintenance costs and system idleness. In this work, refractory concretes with different compositions were characterized and then tested by dilatometry, for compressive strength and in assays involving adherence between tensile concrete/metal inserts, simulating the fixing system in boilers. Analysis of the results showed that refractory concretes do not present retraction due to air during drying, eliminating the possibility of cracking. While casting the plate/prototype with metal inserts, satisfactory concrete/metal adherence was verified and surface cracking occurred that did not influence the tensile bond strength between the insert and the concrete. (author)

  7. 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...

  8. Catalytic and chemical properties of boiler deposits from Orimulsion{sup TM} fuel

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, S.B. [Technical Univ. of Denmark (Denmark). Dept. of Chemistry; Hagen, S.U.; Masters, S.G.; Hagen, A.; Staahl, K.; Eriksen, K.M.; Simonsen, P.; Jensen, J.N.; Berg, M.; Fehrmann, R.; Chorkendorff, I.

    2003-06-01

    Bulk and surface analyses have been conducted for selected deposit samples from an Orimulsion{sup TM} fired boiler unit at the Asnaes power plant in Kalundborg, Denmark. Analyses of the composition show that the deposits on the boiler tubes contain significant quantities of vanadium, calcium, nickel and sulfur. Furthermore the SO{sub 2} oxidation activity of the collected samples has been measured as a function of oxygen and SO{sub 2} content in the flue gas and of the gas temperature. The results show a significant SO{sub 2} oxidation capability in the temperature range 530-670 C. The catalytic oxidation reaction on the deposits is found to be a gas-solid, heterogeneously catalyzed reaction. The catalytically active species have been determined as surface oxo vanadium compounds with vanadium in a formal oxidation state between +IV and +V. (orig.)

  9. [Functional aspects of pelvic floor surgery].

    Science.gov (United States)

    Wagenlehner, F M E; Gunnemann, A; Liedl, B; Weidner, W

    2009-11-01

    Pelvic floor dysfunctions are frequently seen in females. The human pelvic floor is a complex structure and heavily stressed throughout female life. Recent findings in the functional anatomy of the pelvic floor have led to a much better understand-ing, on the basis of which enormous improvements in the therapeutic options have arisen. The pelvic floor activity is regulated by three main muscular forces that are responsible for vaginal tension and suspension of the pelvic floor -organs, bladder and rectum. For different reasons laxity in the vagina or its supporting ligaments as a result of altered connective tissue can distort this functional anatomy. A variety of symptoms can derive from these pelvic floor dysfunctions, such as urinary urge and stress incontinence, abnormal bladder emptying, faecal incontinence, obstructive bowel disease syndrome and pelvic pain. Pelvic floor reconstruction is nowadays driven by the concept that in the case of pelvic floor symptoms restoration of the anatomy will translate into restoration of the physiology and ultimately improve the patients' symptoms. The exact surgical reconstruction of the anatomy is there-fore almost exclusively focused on the restoration of the lax pelvic floor ligaments. An exact identification of the anatomic lesions preoperatively is eminently necessary, to allow for an exact anatomic reconstruction with respect to the muscular forces of the pelvic floor.

  10. Application of 1-hydroxyethylidene-1, 1-diphosphonic acid in boiler water for industrial boilers.

    Science.gov (United States)

    Zeng, Bin; Li, Mao-Dong; Zhu, Zhi-Ping; Zhao, Jun-Ming; Zhang, Hui

    2013-01-01

    The primary method used for boiler water treatment is the addition of chemicals to industrial boilers to prevent corrosion and scaling. The static scale inhibition method was used to evaluate the scale inhibition performance of 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP). Autoclave static experiments were used to study the corrosion inhibition properties of the main material for industrial boilers (20# carbon steel) with an HEDP additive in the industrial boiler water medium. The electrochemical behavior of HEDP on carbon steel corrosion control was investigated using electrochemical impedance spectroscopy and Tafel polarization techniques. Experimental results indicate that HEDP can have a good scale inhibition effect when added at a quantity of 5 to 7 mg/L at a test temperature of not more than 100 °C. To achieve a high scale inhibition rate, the HEDP dosage must be increased when the test temperature exceeds 100 °C. Electrochemical and autoclave static experimental results suggest that HEDP has a good corrosion inhibition effect on 20# carbon steel at a concentration of 25 mg/L. HEDP is an excellent water treatment agent.

  11. Time-resolved analysis of primary volatile emissions and secondary aerosol formation potential from a small-scale pellet boiler

    Science.gov (United States)

    Czech, Hendryk; Pieber, Simone M.; Tiitta, Petri; Sippula, Olli; Kortelainen, Miika; Lamberg, Heikki; Grigonyte, Julija; Streibel, Thorsten; Prévôt, André S. H.; Jokiniemi, Jorma; Zimmermann, Ralf

    2017-06-01

    Small-scale pellet boilers and stoves became popular as a wood combustion appliance for domestic heating in Europe, North America and Asia due to economic and environmental aspects. Therefore, an increasing contribution of pellet boilers to air pollution is expected despite their general high combustion efficiency. As emissions of primary organic aerosol (POA) and permanent gases of pellet boilers are well investigated, the scope of this study was to investigate the volatile organic emissions and the formation potential of secondary aerosols for this type of appliance. Fresh and aged emissions were analysed by a soot-particle aerosol time-of-flight mass spectrometry (SP-AMS) and the molecular composition of the volatile precursors with single-photon ionisation time-of-flight mass spectrometry (SPI-TOFMS) at different pellet boiler operation conditions. Organic emissions in the gas phase were dominated by unsaturated hydrocarbons while wood-specific VOCs, e.g. phenolic species or substituted furans, were only detected during the starting phase. Furthermore, organic emissions in the gas phase were found to correlate with fuel grade and combustion technology in terms of secondary air supply. Secondary organic aerosols of optimised pellet boiler conditions (OPT, state-of-the-art combustion appliance) and reduced secondary air supply (RSA, used as a proxy for pellet boilers of older type) were studied by simulating atmospheric ageing in a Potential Aerosol Mass (PAM) flow reactor. Different increases in OA mass (55% for OPT, 102% for RSA), associated with higher average carbon oxidation state and O:C, could be observed in a PAM chamber experiment. Finally, it was found that derived SOA yields and emission factors were distinctly lower than reported for log wood stoves.

  12. 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

  13. Large CFB Boilers with Good Prospects in China

    Institute of Scientific and Technical Information of China (English)

    Zhao Changsui

    2007-01-01

    @@ Since many CFB boilers have been put into use, there exist a number of problems urgent to be solved. Based on investigation and analysis on the operating condition of large CFB boilers, ten kinds of the common problems are summed up and relative countermeasures are put forward.

  14. 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....

  15. 21 CFR 173.310 - Boiler water additives.

    Science.gov (United States)

    2010-04-01

    ... CONSUMPTION Specific Usage Additives § 173.310 Boiler water additives. Boiler water additives may be safely... Applied Nutrition's Library, Food and Drug Administration, 5100 Paint Branch Pkwy., College Park, MD 20740... Center for Food Safety and Applied Nutrition's Library, Food and Drug Administration, 5100 Paint...

  16. Water Boiler Change-Over in Mini-TPP Mode

    Directory of Open Access Journals (Sweden)

    B. A. Bayrashevsky

    2011-01-01

    Full Text Available The paper considers water boiler modernization by its change-over in mini-TPP mode with an expansion tank and a heating turbine of small capacity.  A software complex permitting to evaluate competitive ability of such water boiler modernization in comparison with a cogeneration plant.

  17. 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.

  18. 46 CFR 115.812 - Pressure vessels and boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Pressure vessels and boilers. 115.812 Section 115.812 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL PASSENGER VESSELS CARRYING MORE... CERTIFICATION Material Inspections § 115.812 Pressure vessels and boilers. (a) Pressure vessels must be...

  19. 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....

  20. DESIGN REPORT: LOW-NOX BURNERS FOR PACKAGE BOILERS

    Science.gov (United States)

    The report describes a low-NOx burner design, presented for residual-oil-fired industrial boilers and boilers cofiring conventional fuels and nitrated hazardous wastes. The burner offers lower NOx emission levels for these applications than conventional commercial burners. The bu...

  1. Development of laser diagnostics for in situ measurements of entrained particles in recovery boilers.

    Energy Technology Data Exchange (ETDEWEB)

    Holve, Donald J. (Process Metrix LLC, San Ramon, CA); Shaddix, Christopher R.

    2004-03-01

    As part of the U.S. Department of Energy (DOE) Office of Industrial Technologies (OIT) Industries of the Future (IOF) Forest Products research program, two different laser diagnostic techniques have been implemented in pulp mill recovery boilers to provide important information on entrained particles. One technique, based on single-particle scattering of a low-power, continuous-wave (cw) laser source, measures the velocity, concentration, and size distribution of particles within the furnace flow, over a predetermined range of particle sizes. For application to recovery boilers, this technique was designed to measure the range of particle sizes known as intermediate size particles (ISPs), roughly from 2-100 {micro}m in diameter. The other diagnostic technique, known as laser-induced breakdown spectroscopy (LIBS), uses a pulsed, high-power laser beam to create a localized plasma spark in the flow, allowing the measurement of the elemental composition of the entrained particles. This technique is most sensitive for particles less than 10 {micro}m in diameter. Implementing these laser diagnostic techniques in recovery boilers proved to be challenging. For the particle scattering measurement, the use of a narrow aperture for measurement of the forward scattered light was postulated and later confirmed to be effective in minimizing background signals associated with the dense sodium fume in the boilers. For the LIBS measurement, a new water-jacketed optics probe was implemented to allow for measurements with an insertion depth of up to two meters in the furnace. Fume particle deposition on the exposed optics at the end of the LIBS probe was problematic but improved with a redesign of the probe geometry and purge flow. Both diagnostic techniques were employed at two representative recovery boilers. The particle scattering diagnostic demonstrated similar trends in mean ISP concentration, ISP size distribution, and temporal variation of ISP concentration at the two boilers

  2. 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.

  3. Controlling formaldehyde emissions with boiler ash.

    Science.gov (United States)

    Cowan, Jennifer; Abu-Daabes, Malyuba; Banerjee, Sujit

    2005-07-01

    Fluidized wood ash reduces formaldehyde in air from about 20 to formaldehyde reduction increases with increasing moisture content of the ash. Sorption of formaldehyde to ash can be substantially accounted for by partitioning to the water contained in the ash followed by rate-controlling binding to the ash solids. Adsorption occurs at temperatures of up to 165 degrees C; oxidation predominates thereafter. It is proposed that formaldehyde could be stripped from an air stream in a fluidized bed containing ash, which could then be returned to a boiler to incinerate the formaldehyde.

  4. Selecting Actuator Configuration for a Benson Boiler

    DEFF Research Database (Denmark)

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

    2009-01-01

    This paper addresses the problem of an optimal actuator configuration in an economic perspective. The objective is to minimize the economical cost of operating a given plant. Functionals encapsulating information of the business objectives given the different actuators has been established...... with particular focus on a boiler in a power plant operated by DONG Energy - a Danish energy supplier. The problem has been reformulated using mathematic notions from economics. The selection of actuator configuration has been limited to the fuel system which in the considered plant consists of three different...

  5. Conversion of a recovery boiler to bark burning

    Energy Technology Data Exchange (ETDEWEB)

    Barsin, J.A.; Pottera, J.; Stewart, G.

    1988-03-01

    Georgia-Pacific (GP) operates a large integrated pulp and paper mill in Crossett, Ark., which produces in excess of 1400 dry tons/day of various grades of bleached kraft paper. Steam generation in the mill is approximately 1.2 million lb/h, which is supplied by a 1500-ton recovery boiler, a 400,000-lb/h wood-waste boiler, and two power boilers. Because GP wanted to minimize its use of natural gas as a boiler fuel and because it had a retired recovery boiler which could be converted, the decision was made to proceed with this fuel conversion product as a means of reducing energy costs per ton of product. This paper also discusses the biomass fuel handling system.

  6. Composition

    DEFF Research Database (Denmark)

    2014-01-01

    Memory Pieces are open compositions to be realised solo by an improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". Caution: streaming the sound files will in some cases only provide a few minutes' sample. Please DOWNLOAD them to hear them...

  7. Composition

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2010-01-01

    New Year is an open composition to be realised by improvising musicians. It is included in "From the Danish Seasons" (see under this title). See more about my composition practise in the entry "Composition - General Introduction". This work is licensed under a Creative Commons "by-nc" License. You...

  8. Composition

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2011-01-01

    Strategies are open compositions to be realised by improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". Caution: streaming the sound files will in some cases only provide a few minutes' sample. Please DOWNLOAD them to hear them in full...

  9. The pelvic floor in health and disease.

    OpenAIRE

    Shelton, A A; Welton, M L

    1997-01-01

    Normal pelvic floor function involves a set of learned and reflex responses that are essential for the normal control and evacuation of stool. A variety of functional disturbances of the pelvic floor, including incontinence and constipation, are not life threatening, but can cause significant distress to affected patients. Understanding the normal anatomy and physiology of the pelvic floor is essential to understanding and treating these disorders of defecation. This article describes the nor...

  10. 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.

  11. Pelvic floor muscle rehabilitation using biofeedback.

    Science.gov (United States)

    Newman, Diane K

    2014-01-01

    Pelvic floor muscle exercises have been recommended for urinary incontinence since first described by obstetrician gynecologist Dr. Arnold Kegel more than six decades ago. These exercises are performed to strengthen pelvic floor muscles, provide urethral support to prevent urine leakage, and suppress urgency. In clinical urology practice, expert clinicians also teach patients how to relax the muscle to improve bladder emptying and relieve pelvic pain caused by muscle spasm. When treating lower urinary tract symptoms, an exercise training program combined with biofeedback therapy has been recommended as first-line treatment. This article provides clinical application of pelvic floor muscle rehabilitation using biofeedback as a technique to enhance pelvic floor muscle training.

  12. Oil condensation boilers and problems with sulphur. Sulphur separation for oil-fired condensation boilers and flue gas scrubbers - six measurements at different boilers

    Energy Technology Data Exchange (ETDEWEB)

    Koebel, M.; Elsener, M.

    1988-11-01

    Three condensation boilers, one condensating scrubber boiler and two waste gas scrubbers were the objects of measurements made to determine to what degree sulphur is separated. The three condensation boilers which are only equipped with a condenser for the condensation of the combustion water shaved separation levels of between 0.5 and 3.5%. They are therefore not suitable for cutting the SO/sub 2/-emissions from the combustion of sulphur-containing fuel oil. The washer boilers showed better results (40-45%) despite the fact that it works with acid washing liquid (2.85 pH). To explain the high level of separation one must assume that under oxygen influence a large part of the sulphur dioxide is further oxidised to sulphuric acid. Alkaline washers showed very good separations of up to 90%. Here again a large part of the sulphur dioxide further oxidises to sulfates.

  13. 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.

  14. 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.

  15. Growth and property development of convection pass deposits in recovery boilers : final project project.

    Energy Technology Data Exchange (ETDEWEB)

    Lien, Steve J. (Georgia Institute of Technology, Atlanta, GA); Baxter, Larry L.; Frederick, W. James Jr. (Georgia Institute of Technology, Atlanta, GA); Wessel, Richard A. (Babcock & Wilcox Company, Barberton, OH)

    2004-11-01

    As part of the U.S. Department of Energy (DOE) Office of Industrial Technologies (OIT) Industries of the Future (IOF) Forest Products research program, the mechanisms of particle deposition and properties of deposits that form in the convection passes of recovery boilers were investigated. Research from experimental facilities at Sandia National Laboratories, the Institute of Paper Science and Technology (IPST), and the University of Toronto (U of T) was coordinated into a single effort to define the controlling mechanisms and rates of deposition. Deposition rates were recorded on a volumetric and mass basis in a Sandia facility for particle sizes in the range of 0.1 to 150 {micro}m. Deposit thickness, mass, spectral emissivity, thermal conductivity, surface temperature, and apparent density were monitored simultaneously and in situ on instrumented probes that allow determination of heat flux and probe surface temperature. Particle composition and mass deposition rates were also recorded in a U of T facility for particle sizes in the range of 100 to 600 {micro}m. These measurements allowed determination of the liquid content and sticking efficiency of carryover particles that inertially impact on a deposition probe. In addition, information on particulates, stable gas species, gas temperature and velocity were obtained from field tests in an operating recovery boiler. The results were used to develop algorithms appropriate for use in computer codes that simulate recovery boilers. Representative calculations were performed using B&W's comprehensive recovery boiler model to demonstrate the use of the algorithms in such computer codes. Comparisons between observations in commercial systems and model predictions were made to identify algorithm strengths and weaknesses.

  16. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman; J. Shingledecker; J. Sarver; G. Stanko; M. Borden; W. Mohn; S. Goodstine; I. Perrin

    2005-01-31

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). The project goal initially was to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi), although this goal for the main steam temperature had to be revised down to 732 C (1350 F), based on a preliminary assessment of material capabilities. The project is intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This report provides a quarterly status report for the period of July 1 to September 30, 2004.

  17. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman; J. Shingledecker; J. Sarver; G. Stanko; M. Borden; W. Mohn; S. Goodstine; I. Perrin

    2005-10-27

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). A limiting factor in this can be the materials of construction. The project goal is to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi). This goal seems achievable based on a preliminary assessment of material capabilities. The project is further intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This report provides a quarterly status report for the period of July 1 to September 30, 2005.

  18. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman; J. Shingledecker; J. Sarver; G. Stanko; M. Borden; W. Mohn; S. Goodstine; I. Perrin

    2005-08-01

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). A limiting factor in this can be the materials of construction. The project goal is to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi). This goal seems achievable based on a preliminary assessment of material capabilities. The project is further intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This report provides a quarterly status report for the period of April 1 to June 30, 2005.

  19. Boiler Materials for Ultrasupercritical Coal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman; J. Shingledecker; J. Sarver; G. Stanko; M. Borden; W. Mohn; S. Goodstine; I. Perrin

    2006-07-17

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). A limiting factor in this can be the materials of construction. The project goal is to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi). This goal seems achievable based on a preliminary assessment of material capabilities. The project is further intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This report provides a quarterly status report for the period of April 1 to June 30, 2006.

  20. Boiler Materials for Ultrasupercritical Coal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman; J. Shingledecker; J. Sarver; G. Stanko; M. Borden; W. Mohn; S. Goodstine; I. Perrin

    2006-04-20

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). A limiting factor in this can be the materials of construction. The project goal is to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi). This goal seems achievable based on a preliminary assessment of material capabilities. The project is further intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This report provides a quarterly status report for the period of January 1 to March 31, 2006.

  1. Boiler Materials for Ultrasupercritical Coal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman; J. Shingledecker; J. Sarver; G. Stanko; M. Borden; W. Mohn; S. Goodstine; I. Perrin

    2006-01-31

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). A limiting factor in this can be the materials of construction. The project goal is to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi). This goal seems achievable based on a preliminary assessment of material capabilities. The project is further intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This report provides a quarterly status report for the period of October 1 to December 30, 2005.

  2. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman; J. Shingledecker; J. Sarver; G. Stanko; W. Mohn; M. Borden; S. Goodstine; I. Perrin

    2004-04-23

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). The project goal initially was to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi), although this goal for the main steam temperature had to be revised down to 732 C (1350 F), based on a preliminary assessment of material capabilities. The project is intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This report provides a quarterly status report for the period of October 1 to December 30, 2003.

  3. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman; J. Shingledecker; J. Sarver; G. Stanko; W. Mohn; M. Borden; S. Goodstine; I. Perrin

    2004-07-30

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). The project goal initially was to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi), although this goal for the main steam temperature had to be revised down to 732 C (1350 F), based on a preliminary assessment of material capabilities. The project is intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This report provides a quarterly status report for the period of April to June 30, 2004.

  4. Boiler Materials For Ultrasupercritical Coal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman; J. Shingledecker; J. Sarver; G. Stanko; M. Borden; W. Mohn; S. Goodstine; I. Perrin

    2006-09-30

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have recently initiated a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired boilers capable of operating at much higher efficiencies than current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of ultrasupercritical steam conditions (USC). A limiting factor in this can be the materials of construction. The project goal is to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760 C (1400 F)/35 MPa (5000 psi). This goal seems achievable based on a preliminary assessment of material capabilities. The project is further intended to build further upon the alloy development and evaluation programs that have been carried out in Europe and Japan. Those programs have identified ferritic steels capable of meeting the strength requirements of USC plants up to approximately 620 C (1150 F) and nickel-based alloys suitable up to 700 C (1300 F). In this project, the maximum temperature capabilities of these and other available high-temperature alloys are being assessed to provide a basis for materials selection and application under a range of conditions prevailing in the boiler. This report provides a quarterly status report for the period of July 1 to September 30, 2006.

  5. 49 CFR 230.20 - Alteration and repair report for steam locomotive boilers.

    Science.gov (United States)

    2010-10-01

    ... boilers. (a) Alterations. When an alteration is made to a steam locomotive boiler, the steam locomotive... steam locomotive boiler, the steam locomotive owner and/or operator shall file with the FRA Regional... the boiler. Whenever welded or riveted repairs are performed on stayed portions of a steam...

  6. 46 CFR 52.20-17 - Opening between boiler and safety valve (modifies PFT-44).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Opening between boiler and safety valve (modifies PFT-44). 52.20-17 Section 52.20-17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING POWER BOILERS Requirements for Firetube Boilers § 52.20-17 Opening between boiler and safety...

  7. 46 CFR 91.15-1 - Standards in inspection of hulls, boilers, and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Standards in inspection of hulls, boilers, and machinery... hulls, boilers, and machinery. In the inspection of hulls, boilers, and machinery of vessels, the..., respecting material and inspection of hulls, boilers, and machinery, and the certificate of...

  8. 46 CFR 189.15-1 - Standards in inspection of hulls, boilers, and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Standards in inspection of hulls, boilers, and machinery... inspection of hulls, boilers, and machinery. In the inspection of hulls, boilers, and machinery of vessels... chapter, respecting material and construction of hulls, boilers, and machinery, and certificate...

  9. 46 CFR 71.15-1 - Standards in inspection of hulls, boilers, and machinery.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Standards in inspection of hulls, boilers, and machinery..., boilers, and machinery. In the inspection of hulls, boilers, and machinery of vessels, the standards... and inspection of hulls, boilers, and machinery, and the certificate of classification...

  10. Room temperature zeolitization of boiler slag from a Bulgarian thermal power plant

    Directory of Open Access Journals (Sweden)

    Pascova Radost D.

    2017-01-01

    Full Text Available A simple and cost-effective method was applied for the synthesis of zeolite composites utilising wet bottom boiler slag from the Bulgarian coal-fired thermal power plant “Sviloza”, near the town of Svishtov. The method consisted of a prolonged alkali treatment at room temperature of this waste. Experimental techniques, such as scanning electron microscopy, energy-dispersive X-ray and X-ray diffraction analyses, are employed to characterize the initial slag and the final products with respect to their morphology, and elemental and mineral compositions. The composites synthesized in this way contained two Na-type zeolite phases: zeolite X (type FAU and zeolite Linde F (type EDI. The zeolited products and the starting slag were tested as adsorbents for a textile dye (Malachite Green from aqueous solutions. In comparison with the initial slag, the zeolite composite possessed substantially better adsorption properties: it almost completely adsorbs the dye in much shorter times. The results of this investigations revealed a new, easy and low cost route for recycling boiler slag into a material with good adsorption characteristics, which could find different applications, e.g., for purifying polluted waters, including those from the textile industry.

  11. Effects of floor design and floor cleaning on ammonia emission from cubicle houses for dairy cows

    NARCIS (Netherlands)

    Braam, C.R.; Ketelaars, J.J.M.H.; Smits, M.C.J.

    1997-01-01

    The traditional slatted floor was compared with 2 different solid floor systems: a non-sloped (L) and a 3% one-sided sloped floor (S), combined with a highly frequent (96 times/day) or normal (12 times/day) removal of manure by a scraper. NH3 emissions were measured continuously over 2 separate 2-we

  12. Apparatus and method of controlling the thermal performance of an oxygen-fired boiler

    Energy Technology Data Exchange (ETDEWEB)

    Levasseur, Armand A.; Kang, Shin G.; Kenney, James R.; Edberg, Carl D.

    2017-09-05

    Disclosed herein is a method of controlling the operation of an oxy-fired boiler; the method comprising combusting a fuel in a boiler; producing a heat absorption pattern in the boiler; discharging flue gases from the boiler; recycling a portion of the flue gases to the boiler; combining a first oxidant stream with the recycled flue gases to form a combined stream; splitting the combined stream into several fractions; and introducing each fraction of the combined stream to the boiler at different points of entry to the boiler.

  13. Branding on the Shop Floor

    Directory of Open Access Journals (Sweden)

    Szilvia Gyimóthy

    2010-09-01

    Full Text Available Service branding is a particular form of emotional management, where employees are regarded as adaptable media, who can be trained to convey corporate values while interacting with customers. This paper examines the identity work of butchers during the brand revitalisation campaign of Kvickly, a Danish supermarket chain. During the implementation of the “Best Butcher in Town”-project, Kvickly’s shop floor becomes an engineered servicescape where the norms of good salesmanship must be performed. By documenting the disloyal behaviour of butchers, we demonstrate that the affective commitment towards corporate brand values is closely related with self-enactment opportunities of occupational communities. Total service-orientation threatens butchers’ perception of autonomy and may therefore result in the emergence of resistant sub-cultures.

  14. 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)

  15. 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.

  16. 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.

  17. Biomechanics of the pelvic floor musculature

    NARCIS (Netherlands)

    Janda, S.

    2006-01-01

    The present thesis was motivated by two main goals. The first research goal of the thesis was to understand the complex biomechanical behaviour of the pelvic floor muscles. The second goal was to study the mechanism of the pelvic organ prolapse (genital prolapse). The pelvic floor in humans is a ve

  18. 9 CFR 91.26 - Concrete flooring.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Concrete flooring. 91.26 Section 91.26... LIVESTOCK FOR EXPORTATION Inspection of Vessels and Accommodations § 91.26 Concrete flooring. (a) Pens aboard an ocean vessel shall have a 3 inch concrete pavement, proportioned and mixed to give 2000 psi...

  19. Floor vibrations due to walking loads

    NARCIS (Netherlands)

    Donkervoort, D.R.; Hoenderkamp, J.C.D.; Oosterhout, G.P.C. van

    1999-01-01

    Traditionally floors are designed for static strength and stiffness. Improved methods of construction and design, using high strength-lightweight materials, have resulted in strong and stiff floors that display unsatisfactory dynamic behaviour when exposed to walking loads. The paper discusses a met

  20. [Functional rehabilitation of the pelvic floor].

    Science.gov (United States)

    Minschaert, M

    2003-09-01

    Pelvic floor revalidation is devoted to conserve perineal functions as statics, urinary continence and sexual harmony. The therapeutics includes preventive and curative actions, and is based upon muscular and neuromuscular properties of pelvic floor. The different steps are: information, local muscular work, behavioral education, biofeedback, functional electrostimulation, intraabdominal pressure control. The therapeutics is only continued if clinical improvement is demonstrated after 10 sessions.

  1. Laparoscopic Pelvic Floor Repair Using Polypropylene Mesh

    Directory of Open Access Journals (Sweden)

    Shih-Shien Weng

    2008-09-01

    Conclusion: Laparoscopic pelvic floor repair using a single piece of polypropylene mesh combined with uterosacral ligament suspension appears to be a feasible procedure for the treatment of advanced vaginal vault prolapse and enterocele. Fewer mesh erosions and postoperative pain syndromes were seen in patients who had no previous pelvic floor reconstructive surgery.

  2. Imaging pelvic floor disorders. 2. rev. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Stoker, Jaap [Amsterdam Univ. (Netherlands). Dept. of Radiology; Taylor, Stuart A. [University College Hospital, London (United Kingdom). Dept. of Specialist X-Ray; DeLancey, John O.L. (eds.) [Michigan Univ., Ann Arbor, MI (United States). L4000 Women' s Hospital

    2008-07-01

    This volume builds on the success of the first edition of imaging pelvic floor disorders and is aimed at those practitioners with an interest in the imaging, diagnosis and treatment of pelvic floor dysfunction. Concise textual information from acknowledged experts is complemented by high-quality diagrams and images to provide a thorough update of this rapidly evolving field. Introductory chapters fully elucidate the anatomical basis underlying disorders of the pelvic floor. State of the art imaging techniques and their application in pelvic floor dysfunction are then discussed in detail. Additions since the first edition include consideration of the effect of aging and new chapters on perineal ultrasound, functional MRI and MRI of the levator muscles. The closing sections of the book describe the modern clinical management of pelvic floor dysfunction, including prolapse, urinary and faecal incontinence and constipation, with specific emphasis on the integration of diagnostic and treatment algorithms. (orig.)

  3. Investigation of floor heating with thermal storage

    Institute of Scientific and Technical Information of China (English)

    LIN Zhen-guo; ZHANG Su-yun; FU Xiang-zhao; WANG Yong

    2006-01-01

    Based on experimental data, the energy storage performances of floor radiant heating system were investigated.Based on experimental data, the energy storage performances of floor radiant heating system were investigated. The decrease of indoor air temperature after the stopping of floor heating was compared with that of fan-coil heating system. The increase of indoor air temperature after the stopping of floor cooling system was analyzed. The results show that the floor heating system has good thermal storage performance, which can be used to a night-running model to obtain the energy-saving benefits efficient and economic running cost, and still can be used for "shifting peak load to off-peak" macroscopically.

  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. Improvement of steam temperature control in supercritical once thru boilers

    OpenAIRE

    黒石, 卓司; 藤川, 卓爾

    2009-01-01

     New steam temperature control logic for supercritical once thru boilers was developed from the view point of simplicity similar to that of the conventional sub-critical drum type boilers. Water wall outlet steam temperature can be controlled more easily due to larger specific heat capacity of steam than super heater outlet steam temperature. By dividing temperature control into two parts, one at water wall outlet by fuel flow and the other at SH(super heater) outlet by SH spray flow, boiler ...

  6. Industrial Research of Condensing Unit for Natural Gas Boiler House

    Science.gov (United States)

    Ziemele, Jelena; Blumberga, Dagnija; Talcis, Normunds; Laicane, Ilze

    2012-12-01

    In the course of work industrial research was carried out at the boiler plant A/S "Imanta" where a 10MW passive condensing economizer working on natural gas was installed after the 116MW water boiler. The work describes the design of the condensing economizer and wiring diagram. During the industrial experiment, the following measurements were made: the temperature of water before and after the economizer; the ambient temperature; the quantity of water passing through the economizer; heat, produced by the economizer and water boilers. The work summarizes the data from 2010-2011.

  7. 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...

  8. 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...

  9. 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...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-31

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

  11. 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. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman

    2002-10-15

    The principal objective of this project is to develop materials technology for use in ultrasupercritical (USC) plant boilers capable of operating with 760 C (1400 F), 35 MPa (5000 psi) steam. In the 21st century, the world faces the critical challenge of providing abundant, cheap electricity to meet the needs of a growing global population while at the same time preserving environmental values. Most studies of this issue conclude that a robust portfolio of generation technologies and fuels should be developed to assure that the United States will have adequate electricity supplies in a variety of possible future scenarios. The use of coal for electricity generation poses a unique set of challenges. On the one hand, coal is plentiful and available at low cost in much of the world, notably in the U.S., China, and India. Countries with large coal reserves will want to develop them to foster economic growth and energy security. On the other hand, traditional methods of coal combustion emit pollutants and CO{sub 2} at high levels relative to other generation options. Maintaining coal as a generation option in the 21st century will require methods for addressing these environmental issues. This project has established a government/industry consortium to undertake a five-year effort to evaluate and develop of advanced materials that allow the use of advanced steam cycles in coal-based power plants. These advanced cycles, with steam temperatures up to 760 C, will increase the efficiency of coal-fired boilers from an average of 35% efficiency (current domestic fleet) to 47% (HHV). This efficiency increase will enable coal-fired power plants to generate electricity at competitive rates (irrespective of fuel costs) while reducing CO{sub 2} and other fuel-related emissions by as much as 29%. Success in achieving these objectives will support a number of broader goals. First, from a national prospective, the program will identify advanced materials that will make it possible to

  13. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan; K. Coleman

    2003-01-20

    The principal objective of this project is to develop materials technology for use in ultrasupercritical (USC) plant boilers capable of operating with 760 C (1400 F), 35 MPa (5000 psi) steam. In the 21st century, the world faces the critical challenge of providing abundant, cheap electricity to meet the needs of a growing global population while at the same time preserving environmental values. Most studies of this issue conclude that a robust portfolio of generation technologies and fuels should be developed to assure that the United States will have adequate electricity supplies in a variety of possible future scenarios. The use of coal for electricity generation poses a unique set of challenges. On the one hand, coal is plentiful and available at low cost in much of the world, notably in the U.S., China, and India. Countries with large coal reserves will want to develop them to foster economic growth and energy security. On the other hand, traditional methods of coal combustion emit pollutants and CO{sub 2} at high levels relative to other generation options. Maintaining coal as a generation option in the 21st century will require methods for addressing these environmental issues. This project has established a government/industry consortium to undertake a five-year effort to evaluate and develop of advanced materials that allow the use of advanced steam cycles in coal-based power plants. These advanced cycles, with steam temperatures up to 760 C, will increase the efficiency of coal-fired boilers from an average of 35% efficiency (current domestic fleet) to 47% (HHV). This efficiency increase will enable coal-fired power plants to generate electricity at competitive rates (irrespective of fuel costs) while reducing CO{sub 2} and other fuel-related emissions by as much as 29%. Success in achieving these objectives will support a number of broader goals. First, from a national prospective, the program will identify advanced materials that will make it possible to

  14. BOILER MATERIALS FOR ULTRASUPERCRITICAL COAL POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    R. Viswanathan

    2002-04-15

    The principal objective of this project is to develop materials technology for use in ultrasupercritical (USC) plant boilers capable of operating with 760 C (1400 F), and up to 5500 psi with emphasis upon 35 MPa (5000 psi) steam. In the 21st century, the world faces the critical challenge of providing abundant, cheap electricity to meet the needs of a growing global population while at the same time preserving environmental values. Most studies of this issue conclude that a robust portfolio of generation technologies and fuels should be developed to assure that the United States will have adequate electricity supplies in a variety of possible future scenarios. The use of coal for electricity generation poses a unique set of challenges. On the one hand, coal is plentiful and available at low cost in much of the world, notably in the U.S., China, and India. Countries with large coal reserves will want to develop them to foster economic growth and energy security. On the other hand, traditional methods of coal combustion emit pollutants and CO{sub 2} at high levels relative to other generation options. Maintaining coal as a generation option in the 21st century will require methods for addressing these environmental issues. This project has established a government/industry consortium to undertake a five-year effort to evaluate and develop advanced materials that allow the use of advanced steam cycles in coal-based power plants. These advanced cycles, with steam temperatures up to 760 C, will increase the efficiency of coal-fired boilers from an average of 35% efficiency (current domestic fleet) to 47% (HHV). This efficiency increase will enable coal-fired power plants to generate electricity at competitive rates (irrespective of fuel costs) while reducing CO{sub 2} and other fuel-related emissions by as much as 29%. Success in achieving these objectives will support a number of broader goals. First, from a national prospective, the program will identify advanced

  15. Ash from a pulp mill boiler--characterisation and vitrification.

    Science.gov (United States)

    Ribeiro, Ana S M; Monteiro, Regina C C; Davim, Erika J R; Fernandes, M Helena V

    2010-07-15

    The physical, chemical and mineralogical characterisation of the ash resulting from a pulp mill boiler was performed in order to investigate the valorisation of this waste material through the production of added-value glassy materials. The ash had a particle size distribution in the range 0.06-53 microm, and a high amount of SiO(2) (approximately 82 wt%), which was present as quartz. To favour the vitrification of the ash and to obtain a melt with an adequate viscosity to cast into a mould, different amounts of Na(2)O were added to act as fluxing agent. A batch with 80 wt% waste load melted at 1350 degrees C resulting in a homogeneous transparent green-coloured glass with good workability. The characterisation of the produced glass by differential thermal analysis and dilatometry showed that this glass presents a stable thermal behaviour. Standard leaching tests revealed that the concentration of heavy metals in the leaching solution was lower than those allowed by the Normative. As a conclusion, by vitrification of batch compositions with adequate waste load and additive content it is possible to produce an ash-based glass that may be used in similar applications as a conventional silicate glass inclusively as a building ecomaterial.

  16. Corrosion-resistant tube materials for extended life of openings in recovery boilers

    Energy Technology Data Exchange (ETDEWEB)

    Paul, L.D.; Danielson, M.J.; Harper, S.L. (Babcock and Wilcox Co., Alliance, OH (United States). Research and Development Div.); Barna, J.L. (Babcock and Wilcox Co., Barberton, OH (United States). Fossil Power Div.)

    1993-08-01

    The corrosive conditions causing rapid corrosion of Type 304L stainless steel in tube openings have been duplicated in the laboratory. Alternate materials also have been tested, and some show improved corrosion resistance over Type 304L. Alloy 825 and Alloy 625 composite tubing and Alloy 600 and Alloy 625 weld overlay materials all show promise as a replacement for Type 304L in tube openings. All recovery boilers designed or operated at 8.375 MPa (1,200 psi) and above should consider using these replacement materials for tube openings.

  17. Erosion-Oxidation Response of Boiler Grade Steels: A Mathematical Investigation

    Directory of Open Access Journals (Sweden)

    S. K. Das

    2008-01-01

    Full Text Available A ductile erosion model embodying the mechanisms of erosion involving cutting wear and repeated plastic deformation has been developed to predict erosion rates of boiler grade steels. The issue of erosion-oxidation interaction has also been addressed to further predict the mass loss resulted from this composite mechanism. A deterministic formalism for the kinetics of oxide-scale growth and a probabilistic approach to characterize the material loss are employed to describe simultaneous actions of high-temperature oxidation and mechanical erosion. The model predictions are in good agreement with the published data.

  18. Ash transformation in suspension fired boilers co-firing coal and straw

    DEFF Research Database (Denmark)

    Zheng, Yuanjing; Jensen, Peter Arendt; Jensen, Anker Degn;

    The properties of the ash from co-firing of coal and straw have a large influence on boiler operation, flue gas cleaning equipment and appropriate utilization of the fly ash. A study on the fuel composition and local conditions influence on fly ash properties has been done by making entrained flow...... reactor experiments with co-firing of coal and straw, making mineral and alkali vapor laboratory reactor experiments and by developing a model of KCl reaction with kaolin. The results include correlations that can be used to estimate the speciation of potassium in the fly ash when co-firing straw...

  19. Rapid ignition of fluidized bed boiler

    Science.gov (United States)

    Osborn, Liman D.

    1976-12-14

    A fluidized bed boiler is started up by directing into the static bed of inert and carbonaceous granules a downwardly angled burner so that the hot gases cause spouting. Air is introduced into the bed at a rate insufficient to fluidize the entire bed. Three regions are now formed in the bed, a region of lowest gas resistance, a fluidized region and a static region with a mobile region at the interface of the fluidized and static regions. Particles are transferred by the spouting action to form a conical heap with the carbonaceous granules concentrated at the top. The hot burner gases ignite the carbonaceous matter on the top of the bed which becomes distributed in the bed by the spouting action and bed movement. Thereafter the rate of air introduction is increased to fluidize the entire bed, the spouter/burner is shut off, and the entire fluidized bed is ignited.

  20. 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...

  1. Study of Corrosion in a Biomass Boiler

    Directory of Open Access Journals (Sweden)

    C. Berlanga

    2013-01-01

    Full Text Available Biomass plants, apart from producing energy, help to reduce CO2(g emissions. One of the biggest problems for their development is superheater corrosion due to fuel corrosivity, especially of the straw. This limits both the temperature of the vapour and also the effectiveness of the plant. In order to know more about the reactions which happen inside the boiler of biomass, thermodynamic calculations using software (HSC Chemistry have been carried out. Field tests have been carried out in the Sangüesa Biomass Plant in Navarra (Spain: determination of the types of oxides and the deposits formed on the superheaters tubes as well as a program to measure temperatures. Finally, the global results are discussed.

  2. 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

  3. Orion Ammonia Boiler System Preflight Test Preparations

    Science.gov (United States)

    Levitt, Julia L.

    2017-01-01

    The Environmental Controls and Life Support Systems (ECLSS) branch at Kennedy Space Center (KSC) is currently undergoing preparations for ground testing of the Orion Multi-Purpose Crew Vehicle (MPCV) to prepare its subsystems for EM-1 (Exploration Mission-1). EM-1, Orions second unmanned flight, is a three-week long lunar mission during which the vehicle will complete a 6-day retrograde lunar orbit before returning to Earth. This paper focuses on the work done during the authors 16-week internship with the Mechanical Engineering Branch of KSCs Engineering Directorate. The authors project involved assisting with the preparations for testing the Orion MPCVs ammonia boiler system. The purpose of the ammonia boiler system is to keep the spacecraft sufficiently cool during the reentry portion of its mission, from service module (SM) separation to post-landing. This system is critical for keeping both the spacecraft (avionics and electronics) and crew alive during reentry, thus a successful test of the system is essential to the success of EM-1. XXXX The author was able to draft a detailed outline of the procedure for the ammonia system functional test. More work will need to be done on the vehicle power-up and power-down portions of the procedure, but the ammonia system testing portion of the procedure is thorough and includes vehicle test configurations, vehicle commands, and GSE. The author was able to compile a substantial list of questions regarding the ammonia system functional test with the help of her mentors. A significant number of these questions were answered in the teleconferences with Lockheed Martin.

  4. Composition

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    2014-01-01

    Cue Rondo is an open composition to be realised by improvising musicians. See more about my composition practise in the entry "Composition - General Introduction". Caution: streaming the sound/video files will in some cases only provide a few minutes' sample, or the visuals will not appear at all....... Please DOWNLOAD them to see/hear them in full length! This work is licensed under a Creative Commons "by-nc" License. You may for non-commercial purposes use and distribute it, performance instructions as well as specially designated recordings, as long as the author is mentioned. Please see http...

  5. 46 CFR 52.01-2 - Adoption of section I of the ASME Boiler and Pressure Vessel Code.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Adoption of section I of the ASME Boiler and Pressure...) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-2 Adoption of section I of the ASME Boiler and Pressure Vessel Code. (a) Main power boilers and auxiliary boilers shall be designed,...

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

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, Larry L.

    2008-06-09

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

  7. Emissions from Power Plant and Industrial Boiler Sector

    Data.gov (United States)

    U.S. Environmental Protection Agency — This asset provides hourly data on SO2, NOx, and CO2 emissions; gross load, steam load, and heat input; from electricity generation units and industrial boilers from...

  8. 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.

  9. MIX DESIGN FOR OIL-PALM-BOILER CLINKER (OPBC) CONCRETE

    African Journals Online (AJOL)

    DEPT OF AGRICULTURAL ENGINEERING

    Keywords: Oil-Palm-Boiler Clinker (OPBC), Solid Waste, Mix Design, Lightweight Concrete, ... pality. These solid wastes and by-products, ... alternative to the conventional concrete materi- ... to produce steam to generate electricity for the.

  10. 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...

  11. Energy efficiency in boilers; Eficiencia energetica em caldeiras

    Energy Technology Data Exchange (ETDEWEB)

    Ponte, Ricardo Silva The [Universidade Federal do Ceara (UFCE), Fortaleza, CE (Brazil). Dept. de Engenharia Eletrica], email: ricthe@dee.ufc.br; Barbosa, Marcos Antonio Pinheiro; Rufino, Maria da Gracas [Universidade de Fortaleza (UNIFOR), CE (Brazil). Dept. de Engenharia Eletrica], emails: marcos_apb@unifor.br, gsrufino@unifor.br

    2010-07-01

    The boiler is vapor generator equipment that has been widely used in industrial milieu as in electric energy generation in thermoelectric plants. Since their first conception, the boilers have been changed in order to provide security and energetic efficiency. They can present high losses of energy if they don't be operated according to some criteria. A considerable part of boilers operation cost include fuel expenses. So, the adoption of effective steps in order to reduce fuel consumption is important to industry economy, besides it brings environmental benefits through the reduction of pollution liberation. The present article has the objective of emphasizing the effective steps for the economy of energy in boilers, such as, the regulation of combustion; the control of soot and incrustations; the installation of economizers, air heaters and super heaters; the reduction in purges and reintroduction of condensed steam. (author)

  12. Pelvic floor and sexual male dysfunction

    Directory of Open Access Journals (Sweden)

    Antonella Pischedda

    2013-04-01

    Full Text Available The pelvic floor is a complex multifunctional structure that corresponds to the genito- urinary-anal area and consists of muscle and connective tissue. It supports the urinary, fecal, sexual and reproductive functions and pelvic statics. The symptoms caused by pelvic floor dysfunction often affect the quality of life of those who are afflicted, worsening significantly more aspects of daily life. In fact, in addition to providing support to the pelvic organs, the deep floor muscles support urinary continence and intestinal emptying whereas the superficial floor muscles are involved in the mechanism of erection and ejaculation. So, conditions of muscle hypotonia or hypertonicity may affect the efficiency of the pelvic floor, altering both the functionality of the deep and superficial floor muscles. In this evolution of knowledge it is possible imagine how the rehabilitation techniques of pelvic floor muscles, if altered and able to support a voiding or evacuative or sexual dysfunction, may have a role in improving the health and the quality of life.

  13. Effect of maintenance on boiler efficiency. Technical note

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, J.; Gibbons, C.; Morgan, P.

    1985-01-01

    This study was carried out on fourteen boiler installations under site conditions by monitoring flue-gas oxygen content and temperature together with ambient air temperature to enable the combustion-loss to be calculated. By undertaking the tests on boilers in both clean and dirty conditions, and recording data every minute over a period of two to three days, representative mean combustion-loss figures were obtained.

  14. Performance analysis of heating plants equipped with condensing boilers

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.M.; Schibuola, L.

    1986-01-01

    The behaviour of the condensing boilers is strictly bound to the temperature of the water coming back from the plant. This temperature depends on the control modes and on the meteorological conditions. The seasonal performance has been computed for a heating plant of a building equipped with a condensing boiler simulating the load at short time intervals through a suitable modification of TRNSYS. The study has been carried out in the climate of Padova. For other towns a rough estimate is proposed.

  15. Brief introduction of GEF efficient industrial boiler project in China

    Energy Technology Data Exchange (ETDEWEB)

    Meijian, T.

    1996-12-31

    The present situation of installed industrial boilers, their efficiency and environmental impact are assessed. And the factors contribute to the low efficiency and serious pollution are summarized. Based on WB-assisted GEF project, {open_quotes}Efficient Industrial Boiler Project{close_quotes} aimed at CO{sub 2} mitigation in China, a series of effective measures to bring the GHG emission under control are addressed, in technology, system performance, and operation management aspects.

  16. 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...

  17. Industrial Research of Condensing Unit for Natural Gas Boiler House

    OpenAIRE

    Ziemele, J; Blumberga, D; Talcis, N; Burmistre, I

    2012-01-01

    In the course of work industrial research was carried out at the boiler plant A/S “Imanta” where a 10MW passive condensing economizer working on natural gas was installed after the 116MW water boiler. The work describes the design of the condensing economizer and wiring diagram. During the industrial experiment, the following measurements were made: the temperature of water before and after the economizer; the ambient temperature; the quantity of water passing through ...

  18. An analysis of modern systems for automation of boiler houses

    Science.gov (United States)

    Borisov, G. B.

    2010-06-01

    The situation currently existing in the market of systems for automatic control of boiler houses is analyzed. The objectives and problems of automation are stated. The characteristics of cabinets for automatic control of type DE steam boilers are compared for compliance with the modern requirements for safety and efficiency. The need and effectiveness of using supervisory control and data acquisition systems is shown, especially for supervisory control of a network of territorially distributed facilities.

  19. AUTOMATIC CONTROL SYSTEM OF THE DRUM BOILER SUPERHEATED STEAM TEMPERATURE.

    Directory of Open Access Journals (Sweden)

    Juravliov A.A.

    2006-04-01

    Full Text Available The control system of the temperature of the superheated steam of the drum boiler is examined. Main features of the system are the PI-controller in the external control loop and introduction of the functional component of the error signal of the external control loop with the negative feedback of the error signal between the prescribed value of steam flowrate and the signal of the steam flowrate in the exit of the boiler in the internal control loop.

  20. Ultrasound Imaging of the Pelvic Floor.

    Science.gov (United States)

    Stone, Daniel E; Quiroz, Lieschen H

    2016-03-01

    This article discusses the background and appraisal of endoluminal ultrasound of the pelvic floor. It provides a detailed anatomic assessment of the muscles and surrounding organs of the pelvic floor. Different anatomic variability and pathology, such as prolapse, fecal incontinence, urinary incontinence, vaginal wall cysts, synthetic implanted material, and pelvic pain, are easily assessed with endoluminal vaginal ultrasound. With pelvic organ prolapse in particular, not only is the prolapse itself seen but the underlying cause related to the anatomic and functional abnormalities of the pelvic floor muscle structures are also visualized.

  1. Pulsations, interpulsations, and sea-floor spreading.

    Science.gov (United States)

    Pessagno, E. A., Jr.

    1973-01-01

    It is postulated that worldwide transgressions (pulsations) and regressions (interpulsations) through the course of geologic time are related to the elevation and subsidence of oceanic ridge systems and to sea-floor spreading. Two multiple working hypotheses are advanced to explain major transgressions and regressions and the elevation and subsidence of oceanic ridge systems. One hypothesis interrelates the sea-floor spreading hypothesis to the hypothesis of sub-Mohorovicic serpentinization. The second hypothesis relates the sea-floor spreading hypothesis to a hypothesis involving thermal expansion and contraction.

  2. 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 25~ 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 (e.g. commercial boilers, chillers, motors) that could substantially impact the government’s energy reduction goals. When establishing efficiency recommendations, FEMP looks at standardized performance ratings for products sold in the U.S. marketplace. Currently, the commercial boiler industry uses combustion efficiency and, sometimes, thermal efficiency as metrics when specifying boiler performance. For many years, the industry has used both metrics interchangeably, causing confusion in the market place about boiler performance. This paper discusses the method used to establish FEMP’s efficiency recommendation for commercial boilers in lieu of the various, and somewhat confusing, efficiency ratings currently available. The paper also discusses potential energy cost savings for federal agencies that improve the efficiency of boilers specified and purchased.

  3. 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.

  4. On the design of residential condensing gas boilers

    Energy Technology Data Exchange (ETDEWEB)

    Naeslund, M.

    1997-02-01

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

  5. Notice of construction for proposed backup package boiler

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-01

    The Hanford Site steam plant consists of coal-fired boilers located at the 200 East and the 200 West Areas. These boilers have provided steam to heat and cool facilities in the 200 Areas since the early 1940`s. As part of Project L-017, ``Steam System Rehabilitation, Phase II``, the 200 West Area coal-fired boilers will be permanently shut down. The shut down will only occur after a proposed package backup boiler (50,000 pounds per hour (lb/hr) steam, firing No. 2 oil) is installed at the 200 West Area. The proposed backup boiler will provide back-up services when the 200 East Area steam line, which provides steam to the 200 West Area, is down for maintenance or, when the demand for steam exceeds the supply available from the 200 East Plant. This application is a request for approval to construct and operate the package backup boiler. This request is being made pursuant to Washington Administration Code (WAC) Chapter 173-400, ``General Regulations for Air Pollution Sources``, and Chapter 173-460, ``Controls for New Sources of Toxic Air Pollutants``.

  6. Exhaust gas side corrosion of oil fired central heating boilers

    Energy Technology Data Exchange (ETDEWEB)

    Koebel, M.; Elsener, M.

    1987-09-01

    While Swiss boiler producers aim primarily at achieving low exhaust gas temperatures, in our northern neighbouring country, lower boiler water temperatures are being set as favourite objectives to be met. The first method aims at reducing the exhaust gas losses, i.e. of the heat content of the exhaust gases; the second one aims at reducing service life losses (= losses in the off-air of the boiler). Flue-gas caused corrosion, however, sets practical limits to the energy-saving reduction of the exhaust gas and boiler water temperatures. To be able to define this practical limit more exactly is the main goal of this project which is supported by NEFF and which is carried out in cooperation with the Institute for Energy Engineering of the ETHZ (Professor P. Suter). In addition to this, however, the author also head to find out about sill inexplained cases of corrosion in boilers which are being operated correctly, i.e. with comparably high boiler water and exhaust gas temperatures.

  7. Parameters determination and bolting control of gateway floor

    Institute of Scientific and Technical Information of China (English)

    GOU Pan-feng; XlN Ya-jun

    2011-01-01

    Gateway floor heave control is the key to guarantee mine safe and efficient production.Through analysis of floor instability characteristics and bolting control,gateway floor strata show second level stress under abutment pressure,which causes plastic flow failure in floor strata; gateway floor instability shows mainly shear-break slippage of “triangle sliding body”.Mechanics of floor bolting is mainly a function of connection and combination.Main area of bolting control lies in two gateway floor angles.The paper analyzes mechanics principle of gateway floor instability,constructs stability mechanics model of gateway floor bolting,obtains gateway floor stability criterion of different bolting angles and optimum formula of bolting parameters,carries out the engineering example,and guides better field application.It provides theoretical base for bolting gateway floor instability control.

  8. Do Open Floor Plans Invite Overeating?

    Science.gov (United States)

    ... among American adults. Rollings and Wells suggested that future studies might explore the effect of floor plan openness in settings where overeating can occur, such as residential kitchens; college, school and workplace cafeterias; and buffet-style ...

  9. Constructing international floors for language learning ends ...

    African Journals Online (AJOL)

    ... international floors for language learning ends: reflectng on a teacher upgrading course. ... The researcher, who participated as a teacher trainer in the TRANSNET-RIEP project, used ... Both dialogues were based on pre-reading activities.

  10. 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

  11. 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.

  12. Vaginal childbirth and pelvic floor disorders

    OpenAIRE

    Memon, Hafsa U.; Handa, Victoria L.

    2013-01-01

    Childbirth is an important event in a woman’s life. Vaginal childbirth is the most common mode of delivery and it has been associated with increased incidence of pelvic floor disorders later in life. In this article, the authors review and summarize current literature associating pelvic floor disorders with vaginal childbirth. Stress urinary incontinence and pelvic organ prolapse are strongly associated with vaginal childbirth and parity. The exact mechanism of injury associating vaginal deli...

  13. Anonymous electronic trading versus floor trading

    OpenAIRE

    Franke, Günter; Hess, Dieter

    1995-01-01

    This paper compares the attractiveness of floor trading and anonymous electronic trading systems. It is argued that in times of low information intensity the insight into the order book of the electronic trading system provides more valuable information than floor trading, but in times of high information intensity the reverse is true. Thus, the electronic system's market share in trading activity should decline in times of high information intensity. This hypothesis is tested by data on BUND...

  14. WOODEN FLOORING – BETWEEN PRESENT AND FUTURE

    OpenAIRE

    Ivan CISMARU; Marius FILIPAȘCU; Olimpia-Minerva ȚURCAȘ (DIACONU); Adriana FOTIN

    2015-01-01

    The paper aims at presenting a systematization of the wood floors, both in terms of the areas of application, and in terms of the fastening solutions and structures in constructions. In this respect, an extensive bibliographic research was achieved, on the researchers’ preoccupations. Starting from the current situation and forecasting the future, from the point of view of the chances held by wooden flooring, in competition with other types of materials, we dare say the wooden flo...

  15. Anonymous electronic trading versus floor trading

    OpenAIRE

    Franke, Günter; Hess, Dieter

    1995-01-01

    This paper compares the attractiveness of floor trading and anonymous electronic trading systems. It is argued that in times of low information intensity the insight into the order book of the electronic trading system provides more valuable information than floor trading, but in times of high information intensity the reverse is true. Thus, the electronic system's market share in trading activity should decline in times of high information intensity. This hypothesis is tested by data on BUND...

  16. Total pelvic floor reconstruction during non-nerve-sparing laparoscopic radical prostatectomy: impact on early recovery of urinary continence.

    Science.gov (United States)

    Hoshi, Akio; Nitta, Masahiro; Shimizu, Yuuki; Higure, Taro; Kawakami, Masayoshi; Nakajima, Nobuyuki; Hanai, Kazuya; Nomoto, Takeshi; Usui, Yukio; Terachi, Toshiro

    2014-11-01

    To develop a modified technique of "total pelvic floor reconstruction" during non-nerve-sparing laparoscopic radical prostatectomy, and to determine its effect on postoperative urinary outcomes. A total of 128 patients who underwent non-nerve-sparing laparoscopic radical prostatectomy were evaluated, including 81 with total pelvic floor reconstruction and 47 with non-total pelvic floor reconstruction. Nerve-sparing cases were excluded. Urinary outcomes were assessed with self-administrated questionnaires (Expanded Prostate Cancer Index Composite) at 1, 3, 6 and 12 months after laparoscopic radical prostatectomy. The total pelvic floor reconstruction technique included two concepts involving posterior and anterior reconstructions. In posterior reconstruction, Denonvilliers' fascia was approximated to the bladder neck and the median dorsal raphe by slipknot. The anterior surface of the bladder-neck was approximated to the anterior detrusor apron and the puboprostatic ligament collar for anterior reconstruction. There were no significant differences between the two groups in the patients' characteristics, and in perioperative and oncological outcomes. In the total pelvic floor reconstruction group, the continence rates at 3, 6 and 12 months after laparoscopic radical prostatectomy were 45.7%, 71.4%, and 84.6%, respectively. In the non-total pelvic floor reconstruction group, the continence rates were 26.1%, 46.8% and 60.9%, respectively. The total pelvic floor reconstruction technique resulted in significantly higher continence rates at 3, 6 and 12 months after laparoscopic radical prostatectomy, respectively (all P floor reconstruction group (mean 7.7 months) than in the non-total pelvic floor reconstruction group (mean 9.8 months; P = 0.0003). The total pelvic floor reconstruction technique allows preservation of the blood supply to the urethra and physical reinforcement of the pelvic floor. Therefore, this technique is likely to improve urinary continence

  17. Criteria selection for the assessment of Serbian lignites tendency to form deposits on power boilers heat transfer surfaces

    Directory of Open Access Journals (Sweden)

    Mladenović Milica

    2009-01-01

    Full Text Available Based on investigations of ash deposit formation, semi-empirical indicators for slagging and fouling, based on ash chemical composition and its fusion temperature, have been determined. These criteria-indicators, in suggested limits, describe the coals on which they are based (North-American and British well. However, the experience in the thermal power production sector of Serbia shows that their literal application to domestic coals does not produce satisfactory results. This contribution provides an analysis of applicability and the choice of criteria that are suitable for Serbian coals. The focus of the contribution is on coal slagging indicators, since slagging has much heavier consequences on heat transfer inside the steam boiler, and on boiler operation as a whole. The basis for the analysis of chosen criteria comprises of the results of investigations of four coal fields - Kostolac, Kolubara, Kosovo (Serbia, and Ugljevik (Bosnia and Herzegovina.

  18. Ultra-Supercritical Pressure CFB Boiler Conceptual Design Study

    Energy Technology Data Exchange (ETDEWEB)

    Zhen Fan; Steve Goidich; Archie Robertson; Song Wu

    2006-06-30

    Electric utility interest in supercritical pressure steam cycles has revived in the United States after waning in the 1980s. Since supercritical cycles yield higher plant efficiencies than subcritical plants along with a proportional reduction in traditional stack gas pollutants and CO{sub 2} release rates, the interest is to pursue even more advanced steam conditions. The advantages of supercritical (SC) and ultra supercritical (USC) pressure steam conditions have been demonstrated in the high gas temperature, high heat flux environment of large pulverized coal-fired (PC) boilers. Interest in circulating fluidized bed (CFB) combustion, as an alternative to PC combustion, has been steadily increasing. Although CFB boilers as large as 300 MWe are now in operation, they are drum type, subcritical pressure units. With their sizes being much smaller than and their combustion temperatures much lower than those of PC boilers (300 MWe versus 1,000 MWe and 1600 F versus 3500 F), a conceptual design study was conducted herein to investigate the technical feasibility and economics of USC CFB boilers. The conceptual study was conducted at 400 MWe and 800 MWe nominal plant sizes with high sulfur Illinois No. 6 coal used as the fuel. The USC CFB plants had higher heating value efficiencies of 40.6 and 41.3 percent respectively and their CFB boilers, which reflect conventional design practices, can be built without the need for an R&D effort. Assuming construction at a generic Ohio River Valley site with union labor, total plant costs in January 2006 dollars were estimated to be $1,551/kW and $1,244/kW with costs of electricity of $52.21/MWhr and $44.08/MWhr, respectively. Based on the above, this study has shown that large USC CFB boilers are feasible and that they can operate with performance and costs that are competitive with comparable USC PC boilers.

  19. A novel & affordable interactive floor for educational applications

    DEFF Research Database (Denmark)

    Boisen, Ulrik; Hansen, Anders Juul; Knudsen, Lars;

    2011-01-01

    This article examines two research areas: How interactive floors can be used beneficially in an educational context, and how an interactive floor can be created which is mobile and relatively inexpensive.......This article examines two research areas: How interactive floors can be used beneficially in an educational context, and how an interactive floor can be created which is mobile and relatively inexpensive....

  20. 76 FR 7098 - Dealer Floor Plan Pilot Program

    Science.gov (United States)

    2011-02-09

    ... ADMINISTRATION 13 CFR Parts 120 and 121 Dealer Floor Plan Pilot Program AGENCY: U.S. Small Business... Dealer Floor Plan Pilot Program to make available 7(a) loan guaranties for lines of credit that provide floor plan financing. This new Dealer Floor Plan Pilot Program was created in the Small Business Jobs...

  1. 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.

  2. 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.

  3. Composites

    Science.gov (United States)

    Taylor, John G.

    The Composites market is arguably the most challenging and profitable market for phenolic resins aside from electronics. The variety of products and processes encountered creates the challenges, and the demand for high performance in critical operations brings value. Phenolic composite materials are rendered into a wide range of components to supply a diverse and fragmented commercial base that includes customers in aerospace (Space Shuttle), aircraft (interiors and brakes), mass transit (interiors), defense (blast protection), marine, mine ducting, off-shore (ducts and grating) and infrastructure (architectural) to name a few. For example, phenolic resin is a critical adhesive in the manufacture of honeycomb sandwich panels. Various solvent and water based resins are described along with resin characteristics and the role of metal ions for enhanced thermal stability of the resin used to coat the honeycomb. Featured new developments include pultrusion of phenolic grating, success in RTM/VARTM fabricated parts, new ballistic developments for military vehicles and high char yield carbon-carbon composites along with many others. Additionally, global regional market resin volumes and sales are presented and compared with other thermosetting resin systems.

  4. Statistical Analysis of Tank 5 Floor Sample Results

    Energy Technology Data Exchange (ETDEWEB)

    Shine, E. P.

    2013-01-31

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primary sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, and the radionuclide1, elemental, and chemical concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements

  5. STATISTICAL ANALYSIS OF TANK 5 FLOOR SAMPLE RESULTS

    Energy Technology Data Exchange (ETDEWEB)

    Shine, E.

    2012-03-14

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primary sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, radionuclide, inorganic, and anion concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements above their

  6. Statistical Analysis Of Tank 5 Floor Sample Results

    Energy Technology Data Exchange (ETDEWEB)

    Shine, E. P.

    2012-08-01

    Sampling has been completed for the characterization of the residual material on the floor of Tank 5 in the F-Area Tank Farm at the Savannah River Site (SRS), near Aiken, SC. The sampling was performed by Savannah River Remediation (SRR) LLC using a stratified random sampling plan with volume-proportional compositing. The plan consisted of partitioning the residual material on the floor of Tank 5 into three non-overlapping strata: two strata enclosed accumulations, and a third stratum consisted of a thin layer of material outside the regions of the two accumulations. Each of three composite samples was constructed from five primary sample locations of residual material on the floor of Tank 5. Three of the primary samples were obtained from the stratum containing the thin layer of material, and one primary sample was obtained from each of the two strata containing an accumulation. This report documents the statistical analyses of the analytical results for the composite samples. The objective of the analysis is to determine the mean concentrations and upper 95% confidence (UCL95) bounds for the mean concentrations for a set of analytes in the tank residuals. The statistical procedures employed in the analyses were consistent with the Environmental Protection Agency (EPA) technical guidance by Singh and others [2010]. Savannah River National Laboratory (SRNL) measured the sample bulk density, nonvolatile beta, gross alpha, and the radionuclide, elemental, and chemical concentrations three times for each of the composite samples. The analyte concentration data were partitioned into three separate groups for further analysis: analytes with every measurement above their minimum detectable concentrations (MDCs), analytes with no measurements above their MDCs, and analytes with a mixture of some measurement results above and below their MDCs. The means, standard deviations, and UCL95s were computed for the analytes in the two groups that had at least some measurements

  7. Physical and chemical characterization of residential oil boiler emissions.

    Science.gov (United States)

    Hays, Michael D; Beck, Lee; Barfield, Pamela; Lavrich, Richard J; Dong, Yuanji; Vander Wal, Randy L

    2008-04-01

    The toxicity of emissions from the combustion of home heating oil coupled with the regional proximity and seasonal use of residential oil boilers (ROB) is an important public health concern. Yet scant physical and chemical information about the emissions from this source is available for climate and air quality modeling and for improving our understanding of aerosol-related human health effects. The gas- and particle-phase emissions from an active ROB firing distillate fuel oil (commonly known as diesel fuel) were evaluated to address this deficiency. Ion chromatography of impactor samples showed that the ultrafine ROB aerosol emissions were approximately 45% (w/w) sulfate. Gas chromatography-mass spectrometry detected various n-alkanes at trace levels, sometimes in accumulation mode particles, and out of phase with the size distributions of aerosol mass and sulfate. The carbonaceous matter in the ROB aerosol was primarily light-adsorbing elemental carbon. Gas chromatography-atomic emission spectroscopy measured a previously unrecognized organosulfur compound group in the ROB aerosol emissions. High-resolution transmission electron microscopy of ROB soot indicated the presence of a highly ordered primary particle nanostructure embedded in larger aggregates. Organic gas emissions were measured using EPA Methods TO-15 and TO-11A. The ROB emitted volatile oxygenates (8 mg/(kg of oil burned)) and olefins (5 mg/(kg of oil burned)) mostly unrelated to the base fuel composition. In the final analysis, the ROB tested was a source of numerous hazardous air pollutants as defined in the Clean Air Act Amendments. Approximations conducted using emissions data from the ROB tests show relatively low contributions to a regional-level anthropogenic emissions inventory for volitile organic compounds, PM2.5, and SO2 mass.

  8. 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.

  9. 闭口截面压型钢板组合楼板纵向剪切粘结承载力研究%Longitudinal shear-bond bearing capacity study of cold-formed steel deck and concrete composite floors

    Institute of Scientific and Technical Information of China (English)

    张欣颖; 史庆轩

    2012-01-01

    This paper refers to the normative test method advanced by American ASCE Standard for the Structural Design of Composite Slabs, to use ranges of thickness and shearspanlength,compare of the failure mode under the continuous loading. It show that the longitudinal shearing have greater control function to the shorter shearspanlength test specimen. According to practical dataes, the shear-bond coefficients m & k whichs are characterized by concrete tension strength f1 and the equation for calculating the longitudinal shear-bond bearing capacity is advanced in regression analysis. Experiment results show that this type of cold-formed steel deck has better cooperative capability with the concrete and displacement ductility. So it can be used in engineering.%参照美国ASCE组合楼板结构设计规范提出的标准试验方法,采用不同厚度和不同剪跨的试件进行连续加载,对比其纵向剪切粘结破坏形态及受力性能,发现纵向剪力对小剪跨组合板的破坏有较大的控制作用.采集试验数据并进行回归分析,得到以混凝土抗拉强度值f1表征的试验板型剪切粘结系数m,k,进而提出相应的组合楼板纵向剪切粘结承载力计算公式,为工程应用提供参考.试验表明此类压型钢板与混凝土协调工作较好,且延性较大,能够在实际工程中投入使用.

  10. 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...

  11. How much Energy is Embodied in your Central Heating Boiler?

    Science.gov (United States)

    Koubogiannis, D.; Nouhou, C.

    2016-11-01

    Life Cycle Analysis (LCA) is an important tool in current research to quantitatively assess energy consumption and environmental impact of a building. In the context of LCA, the Embodied Energy (EE) related to the building and the corresponding Embodied CO2 emissions are valuable data. In such a case, these data concern the constitutive materials of the building and any subsystem, component or equipment in it. Usually, after calculating the mass of these materials, embodied energy values are estimated multiplying them by the corresponding EE coefficients concerning the production of these materials (EEMP). However, apart from transportation energy costs, another part of EE is that consumed for the manufacturing of any item as a finished product. The present work focuses on the manufacturing EE (EEMFG) of central heating boilers in Hellenic dwellings. Six typical boilers of different types are studied. Each of them is analyzed to its constitutive materials and its EEMP is estimated. For four of them, the boiler house where it was constructed in Greece was visited and data were collected. Based on them the corresponding boiler EEMFG values are estimated. The results concerning the EE for material production and manufacturing, as well as the results concerning the corresponding ECO2 values are discussed and assessed. Benchmark values correlating EE and ECO2 with the mass or the heat rate of the boiler are extracted.

  12. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-05-11

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

  14. 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.

  15. Slag monitoring system for combustion chambers of steam boilers

    Energy Technology Data Exchange (ETDEWEB)

    Taler, J.; Taler, D. [Cracow University of Technology, Krakow (Poland)

    2009-07-01

    The computer-based boiler performance system presented in this article has been developed to provide a direct and quantitative assessment of furnace and convective surface cleanliness. Temperature, pressure, and flow measurements and gas analysis data are used to perform heat transfer analysis in the boiler furnace and evaporator. Power boiler efficiency is calculated using an indirect method. The on-line calculation of the exit flue gas temperature in a combustion chamber allows for an on-line heat flow rate determination, which is transferred to the boiler evaporator. Based on the energy balance for the boiler evaporator, the superheated steam mass flow rate is calculated taking into the account water flow rate in attemperators. Comparing the calculated and the measured superheated steam mass flow rate, the effectiveness of the combustion chamber water walls is determined in an on-line mode. Soot-blower sequencing can be optimized based on actual cleaning requirements rather than on fixed time cycles contributing to lowering of the medium usage in soot blowers and increasing of the water-wall lifetime.

  16. 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.

  17. Two proposals to determine the efficiency of bagasse boiler

    Energy Technology Data Exchange (ETDEWEB)

    Sosa-Arnao, Juan Harold; Modesto, Marcelo [Universidade Estadual de Campinas (DE/FEM/UNICAMP), SP (Brazil). Fac. de Engenharia Mecanica. Dept. de Energia], e-mail: jhsosa@fem.unicamp.br; Nebra, Silvia A. [State University of Campinas (NIPE/UNICAMP), SP (Brazil). Interdisciplinary Center of Energy Planning], e-mail: silvia.nebra@pesquisador.cnpq

    2006-07-01

    This work analyzes and compares two proposals for determination of the bagasse boiler efficiency, one of it based on bagasse higher heating value (HHV), the other one based on bagasse lower heating value (LHV). The methodology of calculation, for both proposals, uses the heat loss method. The results, obtained through the two proposal's, presented important differences; the boiler efficiency determined through the proposal of code ASME PTC 4.1, based on HHV, highlights the effect of bagasse moisture content upon boiler efficiency. This effect, in the Beaton and Lora proposal, is hidden, because the energy required to evaporate the bagasse moisture content and the water vapour from hydrogen contained in the fuel are discounted in the LHV calculation. Three types of boilers, with different capacity and leaving steam properties were analysed. Considering the boiler constituted by a sequential arrangement of a steam generator, an air heater and an economizer, a simulation was made determining the influence of the variation of the air heater exit gases temperature upon theirs performances. The performance analysis was based on the second law of thermodynamics. (author)

  18. Slagging in a pulverised-coal-fired boiler

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-07-01

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

  19. [Aging-related changes of the female pelvic floor].

    Science.gov (United States)

    Scheiner, David; Betschart, Cornelia; Perucchini, Daniele

    2010-01-01

    The pelvic floor as lower closure of the abdominal cavity has to withstand the abdominal pressure. Meanwhile, the pelvic floor has to allow physiologic functions like micturition, defecation, sexual function and reproduction. But while pregnancy and vaginal delivery damage the pelvic floor directly, chronic stress like caugh, heavy lifting, or obesity lead to a chronic overstraining of the pelvic floor. Aging, structural changes, and possibly estrogen deficiency have a negative impact on the pelvic floor.

  20. Total pelvic floor ultrasound for pelvic floor defaecatory dysfunction: a pictorial review.

    Science.gov (United States)

    Hainsworth, Alison J; Solanki, Deepa; Schizas, Alexis M P; Williams, Andrew B

    2015-01-01

    Total pelvic floor ultrasound is used for the dynamic assessment of pelvic floor dysfunction and allows multicompartmental anatomical and functional assessment. Pelvic floor dysfunction includes defaecatory, urinary and sexual dysfunction, pelvic organ prolapse and pain. It is common, increasingly recognized and associated with increasing age and multiparity. Other options for assessment include defaecation proctography and defaecation MRI. Total pelvic floor ultrasound is a cheap, safe, imaging tool, which may be performed as a first-line investigation in outpatients. It allows dynamic assessment of the entire pelvic floor, essential for treatment planning for females who often have multiple diagnoses where treatment should address all aspects of dysfunction to yield optimal results. Transvaginal scanning using a rotating single crystal probe provides sagittal views of bladder neck support anteriorly. Posterior transvaginal ultrasound may reveal rectocoele, enterocoele or intussusception whilst bearing down. The vaginal probe is also used to acquire a 360° cross-sectional image to allow anatomical visualization of the pelvic floor and provides information regarding levator plate integrity and pelvic organ alignment. Dynamic transperineal ultrasound using a conventional curved array probe provides a global view of the anterior, middle and posterior compartments and may show cystocoele, enterocoele, sigmoidocoele or rectocoele. This pictorial review provides an atlas of normal and pathological images required for global pelvic floor assessment in females presenting with defaecatory dysfunction. Total pelvic floor ultrasound may be used with complementary endoanal ultrasound to assess the sphincter complex, but this is beyond the scope of this review.

  1. 17 CFR 1.62 - Contract market requirement for floor broker and floor trader registration.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Contract market requirement for floor broker and floor trader registration. 1.62 Section 1.62 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION GENERAL REGULATIONS UNDER THE COMMODITY EXCHANGE ACT Miscellaneous § 1...

  2. Orbital floor reconstruction with resorbable polydioxanone implants.

    Science.gov (United States)

    Gierloff, Matthias; Seeck, Niels Gunnar Karl; Springer, Ingo; Becker, StephanThomas; Kandzia, Christian; Wiltfang, Jörg

    2012-01-01

    Many different materials are proposed for reconstruction of traumatic orbital floor defects. Donor-site morbidity of autologous transplants and infections or extrusions of nonresorbable implants lead to a widespread use of resorbable, alloplastic materials such as polydioxanone (PDS). The goal of this study was to evaluate the prevalence of orbital floor fracture-related problems after surgical treatment using PDS. Ophthalmologic and clinical examinations were performed at 194 patients before orbital floor reconstruction, 14 days and 6 months after surgery (approximate defect sizes: 2 cm², n=47). Clinical findings including the ocular motility, the sensibility of the infraorbital nerve, and the position of the globe were evaluated. For statistical analysis of categorical data, confidence intervals of percentages were determined. Linear relationships between 2 variables were assessed with Pearson correlation analysis. A reduced ocular motility was diagnosed in 60 patients (31%) before surgery; in 14 patients (7%), 2 weeks; and in 10 patients (5%), 6 months after surgery. Infraorbital hypesthesia was found in 120 patients (62%) before surgery; in 47 patients (24%), 2 weeks; and in 35 patients (18%), 6 months after surgery. An enophthalmos was present in 10 patients (5%) before surgery, and in 4 patients (2%), 6 months after surgery. Our data suggest that PDS is a suitable implant for orbital floor reconstruction with acceptable low rates of infraorbital hypesthesia, bulbus motility disturbances, and enophthalmos. Polydioxanone can also be used for orbital floor defects exceeding 2 cm².

  3. Glazed Tiles as Floor Finish in Nigeria

    Directory of Open Access Journals (Sweden)

    Toyin Emmanuel AKINDE

    2013-09-01

    Full Text Available Tile is no doubt rich in antiquity; its primordial  show, came as mosaic with primary prospect in sacred floor finish before its oblivion, courtesy of, later consciousness towards wall finish in banquets, kitchens, toilets, restaurants and even bars. Today, its renaissance as floor finish is apparent in private and public architectural structures with prevalence in residential, recreational, commercial, governmental and other spaces. In Nigeria, the use of glazed tiles as floor finish became apparent, supposedly in mid-twentieth century; and has since, witnessed ever increasing demands from all sundry; a development that is nascent and has necessitated its mass  production locally with pockets of firms in the country. The latter however, is a resultant response to taste cum glazed tiles affordability, whose divergent sophistication in design, colour, size and shape is believed preferred to terrazzo, carpet and floor flex tile. Accessible as glazed tile and production is, in recent times; its dearth of a holistic literature in Nigeria is obvious. In the light of the latter, this paper examine glazed tiles as floor finish in Nigeria, its advent, usage, production, challenge, benefit and prospect with the hope of opening further frontier in discipline specifics.

  4. WOODEN FLOORING – BETWEEN PRESENT AND FUTURE

    Directory of Open Access Journals (Sweden)

    Ivan CISMARU

    2015-06-01

    Full Text Available The paper aims at presenting a systematization of the wood floors, both in terms of the areas of application, and in terms of the fastening solutions and structures in constructions. In this respect, an extensive bibliographic research was achieved, on the researchers’ preoccupations. Starting from the current situation and forecasting the future, from the point of view of the chances held by wooden flooring, in competition with other types of materials, we dare say the wooden flooring or the wood in combination with other materials are not likely to be eliminated from the “civil-engineering market”. The wood floors are likely to develop as an application, especially in the area of the “special floors”, specific to the indoor sports or social halls; and even for some industrial sectors, with strict operating conditions (elasticity, thermal insulation, soundproofing that cannot be provided by other types of materials or structures. Starting from this last observation, the paper also aims at submitting current opinions with respect to this type of floors, both in the light of the current databases and in the light of the future researches, to this end

  5. Mekanisme Proses Pemanasan Air Di Dalam Boiler Dengan Mempergunakan Heater Tambahan Untuk Efisiensi Pembakaran

    OpenAIRE

    Helmon Sihombing

    2010-01-01

    Pada proses pemanasan air, air yang berasal dari raw water (air tanah) tidak langsung dibakar didalam boiler. dalam hal ini digunakan peralatan instrumen Deaerator dan economizer yang berfungsi untuk pemanasan awal sebelum dibakar didalam boiler. Fungsi deaerator dan economizer ini adalah sebagai komponen pembantu untuk memanaskan air sebelum dibakar didalam boiler. Apabila pemanasan air langsung dilakukan didalam boiler maka akan membutuhkan waktu yang cukup lama dan menggunakan bahan b...

  6. Effects of Floor Covering Resistance of a Radiant Floor on System Energy and Exergy Performances

    DEFF Research Database (Denmark)

    Kazanci, Ongun Berk; Shukuya, Masanori; Olesen, Bjarne W.

    2016-01-01

    Floor covering resistance (material and thickness) can be influenced by subjective choices (architectural design, interior design, texture, etc.) with significant effects on the performance of a radiant heating and cooling system. To study the effects of floor covering resistance on system...... performance, a water-based radiant floor heating and cooling system (dry, wooden construction) was considered to be coupled to an air-to-water heat pump, and the effects of varying floor covering resistances (0.05 m2K/W, 0.09 m2K/W and 0.15 m2K/W) on system performance were analyzed in terms of energy...... and exergy. In order to achieve the same heating and cooling outputs, higher average water temperatures are required in the heating mode (and lower temperatures in the cooling mode) with increasing floor covering resistance. These temperature requirements decrease the heat pump’s performance (lower...

  7. Composites

    Science.gov (United States)

    Chmielewski, M.; Nosewicz, S.; Pietrzak, K.; Rojek, J.; Strojny-Nędza, A.; Mackiewicz, S.; Dutkiewicz, J.

    2014-11-01

    It is commonly known that the properties of sintered materials are strongly related to technological conditions of the densification process. This paper shows the sintering behavior of a NiAl-Al2O3 composite, and its individual components sintered separately. Each kind of material was processed via the powder metallurgy route (hot pressing). The progress of sintering at different stages of the process was tested. Changes in the microstructure were examined using scanning and transmission electron microscopy. Metal-ceramics interface was clean and no additional phases were detected. Correlation between the microstructure, density, and mechanical properties of the sintered materials was analyzed. The values of elastic constants of NiAl/Al2O3 were close to intermetallic ones due to the volume content of the NiAl phase particularly at low densities, where small alumina particles had no impact on the composite's stiffness. The influence of the external pressure of 30 MPa seemed crucial for obtaining satisfactory stiffness for three kinds of the studied materials which were characterized by a high dense microstructure with a low number of isolated spherical pores.

  8. Steam Boiler: Extended FOCUS Specification and its Verification in Isabelle/HOL

    OpenAIRE

    Maria Spichkova

    2016-01-01

    The main idea of this case study was taken from [1]. This paper represents an extension of the Focus specification [1] of the steam boiler, its translation in Isabelle/HOL [2] and the corresponding formal Isabelle/HOL proofs for the translated specifications, which show that the specified steam boiler architecture fulfills the specified steam boiler requirements.

  9. 46 CFR 78.33-1 - Repairs of boiler and pressure vessels.

    Science.gov (United States)

    2010-10-01

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

  10. 7 CFR 51.2833 - U.S. No. 1 Boilers.

    Science.gov (United States)

    2010-01-01

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

  11. 46 CFR 62.35-20 - Oil-fired main boilers.

    Science.gov (United States)

    2010-10-01

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

  12. 46 CFR 52.01-35 - Auxiliary, donkey, fired thermal fluid heater, and heating boilers.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Auxiliary, donkey, fired thermal fluid heater, and... requirements for miscellaneous boiler types, such as donkey, fired thermal fluid heater, heating boiler, etc... (CONTINUED) MARINE ENGINEERING POWER BOILERS General Requirements § 52.01-35 Auxiliary, donkey, fired...

  13. Characterization and quantification of deposits build up and removal in straw suspension fired boilers

    DEFF Research Database (Denmark)

    Jensen, Peter Arendt; Shafique Bashir, Muhammad; Wedel, Stig;

    : 1) The influence of local boiler conditions on deposit formation in suspension fired boilers using wood or co-firing straw and wood, 2) quantification of deposit removal in biomass suspension firing boilers with regards both to natural shedding and soot blower induced shedding, 3) established...

  14. Aspects of new material application for boilers construction; Aspekty wdrazania nowych materialow w budowie kotlow

    Energy Technology Data Exchange (ETDEWEB)

    Czerniawski, R. [RAFAKO S.A., Raciborz (Poland)

    1996-12-31

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

  15. 46 CFR 97.30-1 - Repairs to boilers and pressure vessels.

    Science.gov (United States)

    2010-10-01

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

  16. 46 CFR 196.30-1 - Repairs to boilers and pressure vessels.

    Science.gov (United States)

    2010-10-01

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

  17. 46 CFR 167.25-1 - Boilers, pressure vessels, piping and appurtenances.

    Science.gov (United States)

    2010-10-01

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

  18. 46 CFR 167.25-5 - Inspection of boilers, pressure vessels, piping and appurtenances.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Inspection of boilers, pressure vessels, piping and...) NAUTICAL SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Marine Engineering § 167.25-5 Inspection of boilers, pressure vessels, piping and appurtenances. The inspection of boilers, pressure vessels, piping and...

  19. 46 CFR 50.05-5 - Existing boilers, pressure vessels or piping systems.

    Science.gov (United States)

    2010-10-01

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

  20. 46 CFR 109.421 - Report of repairs to boilers and pressure vessels.

    Science.gov (United States)

    2010-10-01

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

  1. 46 CFR 196.15-15 - Examination of boilers and machinery.

    Science.gov (United States)

    2010-10-01

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

  2. 46 CFR 97.15-15 - Examination of boilers and machinery.

    Science.gov (United States)

    2010-10-01

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

  3. 46 CFR 78.17-30 - Examination of boilers and machinery.

    Science.gov (United States)

    2010-10-01

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

  4. 46 CFR 32.35-1 - Boilers and machinery-TB/ALL.

    Science.gov (United States)

    2010-10-01

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

  5. 40 CFR 270.66 - Permits for boilers and industrial furnaces burning hazardous waste.

    Science.gov (United States)

    2010-07-01

    ... fuel boiler, or hydrochloric acid production furnace becomes subject to RCRA permit requirements after..., solid fuel boiler, liquid fuel boiler, or hydrochloric acid production furnace demonstrates compliance... computation of destruction and removal efficiency (DRE), in accordance with the DRE formula specified in § 266...

  6. Heat flux distribution on circulating fluidized bed boiler water wall

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The future of circulating fluidized bed (CFB)combustion technology is in raising the steam parameters to supercritical levels.Understanding the heat flux distribution on the water wall is one of the most important issues in the design and operation of supercritical pressure CFB boilers.In the present paper,the finite element analysis (FEA) method is adopted to predict the heat transfer coefficient as well as the heat flux of the membrane wall and the results are validated by direct measurement of the temperature around the tube.Studies on the horizontal heat flux distribution were conducted in three CFB boilers with different furnace size,tube dimension and water temperature.The results are useful in supercritical pressure CFB boiler design.

  7. 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.

  8. The heat exchanger of small pellet boiler for phytomass

    Science.gov (United States)

    Mičieta, Jozef; Lenhard, Richard; Jandačka, Jozef

    2014-08-01

    Combustion of pellets from plant biomass (phytomass) causes various troubles. Main problem is slagging ash because of low melting temperature of ash from phytomass. This problem is possible to solve either improving energetic properties of phytomass by additives or modification of boiler construction. A small-scale boiler for phytomass is different in construction of heat exchanger and furnace mainly. We solve major problem - slagging ash, by decreasing combustion temperature via redesign of pellet burner and boiler body. Consequence of lower combustion temperature is also lower temperature gradient of combustion gas. It means that is necessary to design larger heat exchanging surface. We plane to use underfed burner, so we would utilize circle symmetry heat exchanger. Paper deals design of heat exchanger construction with help of CFD simulation. Our purpose is to keep uniform water flux and combustion gas flux in heat exchanger without zone of local overheating and excess cooling.

  9. Corrosion protection of condensing boilers with organic coatings

    Energy Technology Data Exchange (ETDEWEB)

    Faller, M.; Schicker, M.; Richner, P. [Swiss Federal Laboratories for Materials Testing and Research (EMPA), Duebendorf (Switzerland)

    2000-07-01

    An investigation was conducted into whether organic coatings may be used to provide protection from the corrosive condensate which occurs in condensing boilers. The suitability of various coating systems was investigated in laboratory tests. On the basis of these results, a heat curing phenolic resin was selected for field trials in boilers from various manufacturers. The boilers were operated for up to two years. The condition of the coating was investigated during operation and after completion of the trial period. It was found that the selected coating provides good corrosion protection in areas not exposed to very high temperatures, which is precisely where condensation is most severe and there is thus the greatest risk of corrosion. (orig.)

  10. Economics of fuel alternatives - oil, coal and bark boilers

    Energy Technology Data Exchange (ETDEWEB)

    Knight, W.E.; Jansen, B.M.; May, J.C.

    1984-07-01

    A method for comparing the relative economics of burning oil, bark or wastewood, and coal to generate steam is illustrated through several case plans. It was assumed that a 150,000-lb/h (68 ton/h) boiler will generate 600-psig (4134-kPa), 700 degrees F (371 degrees C) steam, that it will be added to an existing steam generating plant, and that it will be connected to the existing main steam header and to the boiler feedwater discharge header. The scope of new construction is therefore limited to the following equipment and their related structures: boiler, fuel handling, combustion controls, burner, safety system, draft fans, particulate collection, ash handling, stack, foundations. Plans involving bark, wastewood, and coal fuels are based on the assumptions that the plant has

  11. 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.

  12. Imaging of the posterior pelvic floor

    Energy Technology Data Exchange (ETDEWEB)

    Stoker, Jaap [Department of Radiology, Academic Medical Center, University of Amsterdam (Netherlands); Bartram, Clive I.; Halligan, Steve [Intestinal Imaging Centre, St. Mark' s Hospital, London (United Kingdom)

    2002-04-01

    Disorders of the posterior pelvic floor are relatively common. The role of imaging in this field is increasing, especially in constipation, prolapse and anal incontinence, and currently imaging is an integral part of the investigation of these pelvic floor disorders. Evacuation proctography provides both structural and functional information for rectal voiding and prolapse. Dynamic MRI may be a valuable alternative as the pelvic floor muscles are visualised, and it is currently under evaluation. Endoluminal imaging is important in the management of anal incontinence. Both endosonography and endoanal MRI can be used for detection of anal sphincter defects. Endoanal MRI has the advantage of simultaneously evaluating external sphincter atrophy, which is an important predictive factor for the outcome of sphincter repair. Many aspects of constipation and prolapse remain incompletely understood and treatment is partly empirical; however, imaging has a central role in management to place patients into treatment-defined groups. (orig.)

  13. Synthetic biomaterials for pelvic floor reconstruction.

    Science.gov (United States)

    Karlovsky, Matthew E; Kushner, Leslie; Badlani, Gopal H

    2005-09-01

    Pelvic organ prolapse and stress urinary incontinence increase with age. The increasing proportion of the aging female population is likely to result in a demand for care of pelvic floor prolapse and incontinence. Experimental evidence of altered connective tissue metabolism may predispose to pelvic floor dysfunction, supporting the use of biomaterials, such as synthetic mesh, to correct pelvic fascial defects. Re-establishing pelvic support and continence calls for a biomaterial to be inert, flexible, and durable and to simultaneously minimize infection and erosion risk. Mesh as a biomaterial has evolved considerably throughout the past half century to the current line that combines ease of use, achieves good outcomes, and minimizes risk. This article explores the biochemical basis for pelvic floor attenuation and reviews various pelvic reconstructive mesh materials, their successes, failures, complications, and management.

  14. Boiler Tube Corrosion Characterization with a Scanning Thermal Line

    Science.gov (United States)

    Cramer, K. Elliott; Jacobstein, Ronald; Reilly, Thomas

    2001-01-01

    Wall thinning due to corrosion in utility boiler water wall tubing is a significant operational concern for boiler operators. Historically, conventional ultrasonics has been used for inspection of these tubes. Unfortunately, ultrasonic inspection is very manpower intense and slow. Therefore, thickness measurements are typically taken over a relatively small percentage of the total boiler wall and statistical analysis is used to determine the overall condition of the boiler tubing. Other inspection techniques, such as electromagnetic acoustic transducer (EMAT), have recently been evaluated, however they provide only a qualitative evaluation - identifying areas or spots where corrosion has significantly reduced the wall thickness. NASA Langley Research Center, in cooperation with ThermTech Services, has developed a thermal NDE technique designed to quantitatively measure the wall thickness and thus determine the amount of material thinning present in steel boiler tubing. The technique involves the movement of a thermal line source across the outer surface of the tubing followed by an infrared imager at a fixed distance behind the line source. Quantitative images of the material loss due to corrosion are reconstructed from measurements of the induced surface temperature variations. This paper will present a discussion of the development of the thermal imaging system as well as the techniques used to reconstruct images of flaws. The application of the thermal line source coupled with the analysis technique represents a significant improvement in the inspection speed and accuracy for large structures such as boiler water walls. A theoretical basis for the technique will be presented to establish the quantitative nature of the technique. Further, a dynamic calibration system will be presented for the technique that allows the extraction of thickness information from the temperature data. Additionally, the results of the application of this technology to actual water wall

  15. NICKEL SPECIES EMISSION INVENTORY FOR OIL-FIRED BOILERS

    Energy Technology Data Exchange (ETDEWEB)

    Kevin C. Galbreath; Richard L. Schulz; Donald L. Toman; Carolyn M. Nyberg

    2004-01-01

    Representative duplicate fly ash samples were obtained from the stacks of 400-MW and 385-MW utility boilers (Unit A and Unit B, respectively) using a modified U.S. Environmental Protection Agency (EPA) Method 17 sampling train assembly as they burned .0.9 and 0.3 wt% S residual oils, respectively, during routine power plant operations. Residual oil fly ash (ROFA) samples were analyzed for nickel (Ni) concentrations and speciation using inductively coupled plasma-atomic emission spectroscopy, x-ray absorption fine structure (XAFS) spectroscopy, x-ray diffraction (XRD), and a water-soluble Ni extraction method. ROFA water extraction residues were also analyzed for Ni speciation using XAFS and XRD. Total Ni concentrations in the ROFAs were similar, ranging from 1.3 to 1.5 wt%; however, stack gas Ni concentrations in the Unit A were {approx}990 {micro}g/Nm{sup 3} compared to {approx}620 {micro}g/Nm{sup 3} for Unit B because of the greater residual oil feed rates employed at Unit A to attain higher load (i.e., MW) conditions with a lower heating value oil. Ni speciation analysis results indicate that ROFAs from Unit A contain about 3 wt% NiSO{sub 4} {center_dot} xH{sub 2}O (where x is assumed to be 6 for calculation purposes) and a Ni-containing spinel compound, similar in composition to (Mg,Ni)(Al,Fe){sub 2}O{sub 4}. ROFAs from Unit B contain on average 2.0 wt% NiSO{sub 4} {center_dot} 6H{sub 2}O and 1.1 wt% NiO. XAFS and XRD analyses did not detect any nickel sulfide compounds, including nickel subsulfide (Ni{sub 3}S{sub 2}) (XAFS detection limit is 5% of the total Ni concentration). In addition, XAFS measurements indicated that inorganic sulfate and organic thiophene species account for >97% of the total sulfur in the ROFAs. The presence of NiSO{sub 4} {center_dot} xH{sub 2}O and nickel oxide compound mixtures and lack of carcinogenic Ni{sub 3}S{sub 2} or nickel sulfide compounds (e.g., NiS, NiS{sub 2}) in ROFAs stack-sampled from 400- and 385-MW boilers are contrary

  16. Heat losses in power boilers caused by thermal bridges

    Directory of Open Access Journals (Sweden)

    Kocot Monika

    2017-01-01

    Full Text Available In this article the analysis of heat losses caused by thermal bridges that occur in the steam boiler OP-140 is presented. Identification of these bridges were conducted with use of thermographic camera. Heat losses were evaluated based on methodology of VDI 4610 standard, but instead of its simplified equations, criterial equations based on Nusselt number were used. Obtained values of annual heat losses and heat flux density corresponding to the fully insulated boiler surfaces were compared to heat losses generated by thermal bridges located in the same areas. The emphasis is put on the role of industrial insulation in heat losses reduction.

  17. Condition monitoring, diagnostic and controlling tool for boiler feed pump

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Sohail [Siemens AG, Muelheim (Germany). Energy Sector; Leithner, Reinhard; Kosyna, Guenter [TU Braunschweig (Germany)

    2010-07-01

    The boiler feed pump is an important component of a thermal power generation cycle and demands high safety and unquestionable availability for flexible power plant operation. In this research paper, the methodology of a general purpose condition monitoring, diagnostic and controlling tool is presented, which can address the challenges of operational safety and availability as well as optimal operation of a boiler feed pump. This tool not only effectively records the life time consumption of both casings and rotors and monitors the small gaps between casings and rotors but also suggests appropriate actions in order to ensure that the pump operates within the allowable design limits. (orig.)

  18. Use of reactor effluent water as steam plant boiler feed

    Energy Technology Data Exchange (ETDEWEB)

    Clukey, H.V.

    1953-12-08

    The radiological aspects of a proposal to recover some of the heat now wasted in cooling water from the Hanford reactors by using the hot water as boiler feed for the steam plants in the 100 Areas are evaluated. The radioactive material in the hot effluent water will contaminate the boiler feed water system, cause additional radiation exposure of personnel, and increase the cost of maintenance and radiation protection, but very little radioactive material will be carried over into the steam system. At present steam loads, this proposal is economically attractive; other proposals being considered may nullify any savings from this one. 21 refs., 1 fig., 10 tabs.

  19. 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.

  20. Anatomical aspects of sinus floor elevations.

    Science.gov (United States)

    van den Bergh, J P; ten Bruggenkate, C M; Disch, F J; Tuinzing, D B

    2000-06-01

    Inadequate bone height in the lateral part of the maxilla forms a contra-indication for implant surgery. This condition can be treated with an internal augmentation of the maxillary sinus floor. This sinus floor elevation, formerly called sinus lifting, consists of a surgical procedure in which a top hinge door in the lateral maxillary sinus wall is prepared and internally rotated to a horizontal position. The new elevated sinus floor, together with the inner maxillary mucosa, will create a space that can be filled with graft material. Sinus lift procedures depend greatly on fragile structures and anatomical variations. The variety of anatomical modalities in shape of the inner aspect of the maxillary sinus defines the surgical approach. Conditions such as sinus floor convolutions, sinus septum, transient mucosa swelling and narrow sinus may form a (usually relative) contra-indication for sinus floor elevation. Absolute contra-indications are maxillary sinus diseases (tumors) and destructive former sinus surgery (like the Caldwell-Luc operation). The lateral sinus wall is usually a thin bone plate, which is easily penetrated with rotating or sharp instruments. The fragile Schneiderian membrane plays an important role for the containment of the bonegraft. The surgical procedure of preparing the trap door and luxating it, together with the preparation of the sinus mucosa, may cause a mucosa tear. Usually, when these perforations are not too large, they will fold together when turning the trap door inward and upward, or they can be glued with a fibrin sealant, or they can be covered with a resorbable membrane. If the perforation is too large, a cortico-spongious block graft can be considered. However, in most cases the sinus floor elevation will be deleted. Perforations may also occur due to irregularities in the sinus floor or even due to immediate contact of sinus mucosa with oral mucosa. Obstruction of the antro-nasal foramen is, due to its high location, not a

  1. Sea-floor classification using multibeam echo-sounding angular backscatter data: A real-time approach employing hybrid neural network architecture

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, B.; Kodagali, V.N.; Baracho, J.

    The presently studied numerical model, e.g., composite roughness, is successful for the purpose of sea-floor classification employing processed multibeam angular backscatter data from manganese-nodule-bearing locations of the Central Indian Ocean...

  2. Thermal Performance Analysis of Reinforced Concrete Floor Structure with Radiant Floor Heating System in Apartment Housing

    Directory of Open Access Journals (Sweden)

    Young-Sun Jeong

    2015-01-01

    Full Text Available The use of the resilient materials in the radiant floor heating systems of reinforced concrete floor in apartment housing is closely related to the reduction of the floor impact sound and the heating energy loss. This study examined the thermal conductivity of expanded polystyrene (EPS foam used for the resilient material in South Korea and analysed the thermal transfer of reinforced concrete floor structure according to the thermal conductivity of the resilient materials. 82 EPS specimens were used to measure the thermal conductivity. The measured apparent density of EPS resilient materials ranged between 9.5 and 63.0 kg/m3, and the thermal conductivity ranged between 0.030 and 0.046 W/(m·K. As the density of resilient materials made of expanded polystyrene foam increases, the thermal conductivity tends to proportionately decrease. To set up reasonable thermal insulation requirements for radiant heating floor systems, the thermal properties of floor structure according to thermal insulation materials must be determined. Heat transfer simulations were performed to analyze the surface temperature, heat loss, and heat flow of floor structure with radiant heating system. As the thermal conductivity of EPS resilient material increased 1.6 times, the heat loss was of 3.4% increase.

  3. Composition and methods for improved fuel production

    Energy Technology Data Exchange (ETDEWEB)

    Steele, Philip H.; Tanneru, Sathishkumar; Gajjela, Sanjeev K.

    2015-12-29

    Certain embodiments of the present invention are configured to produce boiler and transportation fuels. A first phase of the method may include oxidation and/or hyper-acidification of bio-oil to produce an intermediate product. A second phase of the method may include catalytic deoxygenation, esterification, or olefination/esterification of the intermediate product under pressurized syngas. The composition of the resulting product--e.g., a boiler fuel--produced by these methods may be used directly or further upgraded to a transportation fuel. Certain embodiments of the present invention also include catalytic compositions configured for use in the method embodiments.

  4. Measurements of Selected Air Pollutants in Danish Homes and Ozone Interaction with Floor Dust

    DEFF Research Database (Denmark)

    Vibenholt, Anni

    and a FLEC on a stainless steel plate without dust (kFLEC). The composition of organic compounds in the dust was analyzed by pressurized liquid extraction and thermal desorption GC-MS before and after ozone exposure. KFLEC was independent of the ozone concentration and the reaction was treated as first order...... in the Field and Laboratory Emission Cell (FLEC) at different ozone concentrations and relative humidities (0, 25, and 50 % RH). One gram of dust was spread on a clean stainless steel plate which was placed in the FLEC. Steady state reaction rate (kDust) at 2.2 ppm ozone was determined for four different floor......Section I: Laboratory studies: Chemical and sorption properties of indoor floor dust in FLEC: Ozone reacts with C-C double bonds in common indoor VOCs and SVOCs contained in indoor dust and may be catalytically degraded on dust surfaces. The reaction between floor dust and ozone was investigated...

  5. Branchfall as a Demographic Filter for Epiphyte Communities: Lessons from Forest Floor-Based Sampling.

    Directory of Open Access Journals (Sweden)

    Juliano Sarmento Cabral

    Full Text Available Local variation in the abundance and richness of vascular epiphytes is often attributed to environmental characteristics such as substrate and microclimate. Less is known, however, about the impacts of tree and branch turnover on epiphyte communities. To address this issue, we surveyed branches and epiphytes found on the forest floor in 96 transects in two forests (Atlantic rainforest in Brazil and Caribbean rainforest in Panama. In the Brazilian forest, we additionally distinguished between edge and core study sites. We quantified branch abundance, epiphyte abundance, richness and proportion of adults to investigate the trends of these variables over branch diameter. Branches 90% of all branches on the forest floor. Abundance and richness of fallen epiphytes per transect were highest in the Brazilian core transects and lowest in the Panamanian transects. The majority of epiphytes on the floor (c. 65% were found attached to branches. At all three study sites, branch abundance and branch diameter were negatively correlated, whereas epiphyte abundance and richness per branch, as well as the proportion of adults were positively correlated with branch diameter. The relationship between branch diameter and absolute epiphyte abundance or richness differed between study sites, which might be explained by differences in forest structure and dynamics. In the Panamanian forest, epiphytes had been previously inventoried, allowing an evaluation of our surveying method by comparing canopy and forest floor samplings. Individuals found on the forest floor corresponded to 13% of all individuals on branches <10 cm in diameter (including crowns, with abundance, richness and composition trends on forest floor reflecting canopy trends. We argue that forest floor surveys provide useful floristic and, most notably, demographic information particularly on epiphytes occurring on the thinnest branches, which are least accessible. Here, branchfall acts as an important

  6. 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.

  7. Feasibility of Combustion of Petroleum Coke in 230t/h Circulating Fluidized Bed Boiler

    Institute of Scientific and Technical Information of China (English)

    HAN Dong-tai; SONG Zheng-chang; XU Tao

    2003-01-01

    In order to reuse the high sulfur petroleum coke, the waste in chemical industry, as fuel of power plant for energy recovery, the combustion property of petroleum coke was researched experimentally in circulating fluidized bed (CFB) boiler. The performance of the boiler in burning mixed fuel with different ratios of coal to petroleum coke is obtained. Based on the experimental data, Factors influencing the stability of combustion,thermal efficiency of boiler, and emissions and desulphurisation are discussed. This study demonstrates that the combustion of petroleum coke in CFB boiler is applicable, and has great significance on the design and operation of CFB boiler to burn petroleum coke.

  8. Control of the Bed Temperature of a Circulating Fluidized Bed Boiler by using Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    AYGUN, H.

    2012-05-01

    Full Text Available Circulating fluidized bed boilers are increasingly used in the power generation due to their higher combustion efficiency and lower pollutant emissions. Such boilers require an effective control of the bed temperature, because it influences the boiler combustion efficiency and the rate of harmful emissions. A Particle-Swarm-Optimization-Proportional-Integrative-Derivative (PSO-PID controller for the bed temperature of a circulating fluidized bed boiler is presented. In order to prove the capability of the proposed controller, its performances are compared at different boiler loads with those of a Fuzzy Logic (FL controller. The simulation results demonstrate some advantages of the proposed controller.

  9. 46 CFR 53.01-3 - Adoption of section IV of the ASME Boiler and Pressure Vessel Code.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Adoption of section IV of the ASME Boiler and Pressure...) MARINE ENGINEERING HEATING BOILERS General Requirements § 53.01-3 Adoption of section IV of the ASME Boiler and Pressure Vessel Code. (a) Heating boilers shall be designed, constructed, inspected,...

  10. Operator's Manual, Boiler Room Operations and Maintenance. Supplement A, Air Pollution Training Institute Self-Instructional Course SI-466.

    Science.gov (United States)

    Environmental Protection Agency, Research Triangle Park, NC. Air Pollution Training Inst.

    This Operator's Manual is a supplement to a self-instructional course prepared for the United States Environmental Protection Agency. This publication is the Boiler Room Handbook for operating and maintaining the boiler and the boiler room. As the student completes this handbook, he is putting together a manual for running his own boiler. The…

  11. Free forearm flap and free iliac bone reconstruct the composite tissue defects of the floor of mouth and the lower part of face in the same period%游离前臂皮瓣联合髂骨同期修复重建口底及面下部的复合性组织缺损

    Institute of Scientific and Technical Information of China (English)

    徐锦程; 卢保全; 黄全顺; 李建成; 张凯; 廖圣恺; 徐涛

    2011-01-01

    目的 探讨游离前臂皮瓣联合游离髂骨进行口底及面下部复合型组织缺损同期修复重建的临床疗效。 方法 术前对11例口底及面下部复合型组织缺损的范围及外形进行认真的评估,设计出与缺损区相匹配的个体化前臂皮瓣。术中先行成型钛板恢复缺损下颌骨基本的外形及咬合关系,然后用来复锯切取设计塑型的游离髂骨并移植固定于钛板的内侧,从而恢复缺损下颌骨的连续性。 结果 11例前臂皮瓣及髂骨全部成活,成功率100%。本组患者经随访6~ 12个月,修复区外形虽显不同程度的臃肿,但饮食、吞咽等口腔功能得到了改善,有7例可进普食,有4例可进流质饮食,同时可参与社会活动中日常的语言交流,皮瓣的感觉功能及外形恢复满意。 结论 适形游离前臂皮瓣联合游离髂骨对口底及面下部复合型组织缺损同期修复重建,是修复口底及面下部复合型组织缺损较为理想的方法之一,既达到安全、实用的预后效果,又可明显提高患者的生存质量,值得临床借鉴并使用。%Objective To probe into the clinical efficiency of reconstruction to person who had composite tissue defect of the floor of mouth and the lower part of face with the free forearm flap and free iliac bone in the same term. Methods Before the surgery, the surgeon should carefully evaluate the scope and shape of defects in 11 cases who had the composite tissue defects of the floor of mouth and the lower part of face, to design the individual forearm flap, so that it matches with the defect region. During surgery, the first resumption of defects using titanium plates forming the basic shape of mandible and the occlusal relationship, then used to re-sawing to take modeling of the iliac bone, transplanted free iliac bone and fixed after the inside of the titanium plate, thereby restoring the continuity of mandible missing. Results Free

  12. Modal analysis for floors in lightweight buildings

    DEFF Research Database (Denmark)

    Sjökvist, Lars-Göran; Brunskog, Jonas

    2007-01-01

    constructions usually consist of plates that are stiffened by beams and by the dividing walls. In this study the wave equation for a plate is expanded by Fourier series and an analytical solution in terms of the eigenmodes of the entire system is presented. The studied system consists of one lightweigt floor...

  13. Modal analysis for floors in lightweight buildings

    DEFF Research Database (Denmark)

    Sjökvist, Lars-Göran; Brunskog, Jonas

    2007-01-01

    constructions usually consist of plates that are stiffened by beams and by the dividing walls. In this study the wave equation for a plate is expanded by Fourier series and an analytical solution in terms of the eigenmodes of the entire system is presented. The studied system consists of one lightweigt floor...

  14. Engagement and Floor Control in Hybrid Meetings

    NARCIS (Netherlands)

    op den Akker, Hendrikus J.A.; Devanthéry, V.; Zwiers, Jakob; Hondorp, G.H.W.; van Dijk, Elisabeth M.A.G.; Kulyk, Olga Anatoliyivna; Hofs, D.H.W.; Nijholt, Antinus; Reidsma, Dennis

    2010-01-01

    The Human Media Interaction group of the University of Twente has developed a User Engagment and Floor Control Demonstrator, a system that uses modules for online speech recognition, real-time visual focus of attention as well as a module that signals who is being addressed by the speaker. A

  15. Characterization of Residential Scale Biofuel Boilers and Fuels

    Science.gov (United States)

    Chandrasekaran, Sriraam R.

    The objectives of this study were to: 1) characterize commercially available wood pellets and wood chips for basic properties such as calorific, ash, moisture contents; 2) analyze elements and ions and other possible contamination during the pellet manufacturing processes; 3) characterize the chemical and thermo-chemical property of grass pellets for their combustion potential; 4) characterize the emissions from 6 different residential scale boiler/furnace appliances burning grass and wood pellets; 5) characterize the emitted particulate matter for toxic and marker species with respect to combustion appliance and combustion conditions; and 6) determine the effects of the biomass fuel properties of 5 different grass pellets on particulate and gaseous emissions from a single type of boiler. The results from characterization of wood pellets and chips indicated that the wood pellet samples generally meet the quality standards. However, there are some samples that would fail the ash content requirements. Only the German standards have extensive trace element limits. Most of the samples would meet these standards, but some samples failed to meet these standards based on their lead, arsenic, cadmium, and copper concentrations. It is likely that inclusion of extraneous materials such as painted or pressure treated lumber led to the observed high concentrations. Given increasing use of pellets and chips as a renewable fuel, standards for the elemental composition of commercial wood pellets and chips are needed in United States to avoid the inclusion of extraneous materials. Such standards would reduce the environmental impact of toxic species that would be released when the wood is burned. Grass pellets were characterized for chemical and thermochemical properties. Switch grass pellets were studied for it thermal degradation process under inert and oxidizing atmosphere using TGA. The thermal degradation of grass pellet measured the activation energy and pre

  16. 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.

  17. Recovery Act: Oxy-Combustion Technology Development for Industrial-Scale Boiler Applications

    Energy Technology Data Exchange (ETDEWEB)

    Levasseur, Armand

    2014-01-01

    This Topical Report outlines guidelines and key considerations for design and operation of pulverized coal-fired boilers for oxy-combustion. The scope addressed includes only the boiler island, not the entire oxy-fired CO{sub 2} capture plant. These guidelines are primarily developed for tangential-fired boilers and focus on designs capable of dual air and oxy-fired operation. The guidelines and considerations discussed are applicable to both new units and existing boiler retrofits. These guidelines are largely based on the findings from the extensive 15 MW{sub th} pilot testing and design efforts conducted under this project. A summary level description is provided for each major aspect of boiler design impacted by oxy-combustion, and key considerations are discussed for broader application to different utility and industrial designs. Guidelines address the boiler system arrangement, firing system, boiler thermal design, ducting, materials, control system, and other key systems.

  18. Design trends and operating problems in combustion modification of industrial boilers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Locklin, D.W.; Krause, H.H.; Putnam, A.A.; Kropp, E.L.; Reid, W.T.

    1974-04-01

    The report gives results of an air pollution emissions control study to: characterize the current field population of industrial boilers; identify trends in boiler design; and assess operating problems associated with combustion modification. Statistics were analyzed to describe the field population and recent sales trends for firetube and watertube industrial boilers in the range from 10 million to 500 million Btu/hr. Boiler capacity, design type, mode of direction, primary and secondary fuels, firing method (for coal), industrial classification, and geographic region of the boiler installation were all considered. When combustion modifications are used to control nitrogen oxide emissions from industrial boilers, practical operating problems may arise, namely: fireside corrosion and deposits on boiler tubes; and flame instability, including blow-off, flashback, combustion-driven oscillations, and combustion noise or roar. These problems were assessed and research needs were identified in relation to such combustion modifications as low-excess-air operation, staged combustion, and fluegas recirculation. (GRA)

  19. NOx Control for Utility Boiler OTR Compliance

    Energy Technology Data Exchange (ETDEWEB)

    Hamid Farzan; Jennifer L. Sivy

    2005-07-30

    Babcock & Wilcox Power Generation Group (B&W) and Fuel Tech, Inc. (Fuel Tech) teamed to evaluate an integrated solution for NO{sub x} control comprised of B&W's DRB-4Z{reg_sign} low-NO{sub x} pulverized coal (PC) burner technology and Fuel Tech's NO{sub x}OUT{reg_sign}, a selective non-catalytic reduction (SNCR) technology, capable of meeting a target emission limit of 0.15 lb NO{sub x}/10{sup 6} Btu. In a previous project sponsored by the U.S. Department of Energy (DOE), promising results were obtained with this technology from large-scale testing in B&W's 100-million Btu/hr Clean Environment Development Facility (CEDF) which simulates the conditions of large coal-fired utility boilers. Under the most challenging boiler temperatures at full load conditions, NO{sub x} emissions of 0.19 lb/10{sup 6} Btu were achieved firing Powder River Basin coal while controlling ammonia slip to less than 5 ppm. At a 40 million Btu/hr firing rate, NO{sub x} emissions were as low as 0.09 lb/10{sup 6} Btu. Improved performance with this system was proposed for this new program with injection at full load via a convective pass multiple nozzle lance (MNL) in front of the superheater tubes or in the convective tube bank. Convective pass lances represent the current state-of-the-art in SNCR and needed to be evaluated in order to assess the full potential of the combined technologies. The objective of the program was to achieve a NO{sub x} level below 0.15 lb/10{sup 6} Btu (with ammonia slip of less than 5 ppm) in the CEDF using PRB coal and B&W's DRB-4Z{reg_sign} low-NO{sub x} pulverized coal (PC) burner in combination with dual zone overfire air ports and Fuel Tech's NO{sub x}OUT{reg_sign} System. Commercial installations of B&W's low-NO{sub x} burner, in combination with overfire air ports using PRB coal, have demonstrated a NO{sub x} level of 0.15 to 0.2 lb/10{sup 6} Btu under staged combustion conditions. The proposed goal of the combustion system (no

  20. Functional imaging of the pelvic floor

    Energy Technology Data Exchange (ETDEWEB)

    Lienemann, Andreas E-mail: andreaslienemann@web.de; Fischer, Tanja

    2003-08-01

    Introduction/Objective: Pelvic floor dysfunction and associated pelvic organ prolapse represent a major problem in our present-day society, mostly afflicting parous women. Magnetic resonance imaging (MRI) is assuming an increasingly important role in the more accurate delineation of the extent of the problem. This article briefly reviews one of the main radiological methods for the dynamic evaluation of the pelvic floor: functional cine MRI. Methods and Material: Out of the literature the smallest common denominator for functional cine MRI can be defined as follows: high field system; patient either in supine or sitting position; fast gradient echo sequence; midsagittal slice orientation; either a stack of slices or repeated measurements at the same slice position with the patient at rest or straining; image analysis using the pubococcygeal reference line. Results: All except two publications stress the usefulness of functional cine MRI in the evaluation of patients with organ descent and prolapse. This well accepted method allows for the visualization of all relevant structures in the anterior, middle and posterior compartment. It is especially useful in the detection of enteroceles, and provides a reliable postoperative follow-up tool. Isolated urinary or stool incontinence are not an indication for functional cine MRI, as is the case in patients with equivocal clinical findings. To date it does not allow for real 3D imaging of the pelvic floor or sufficient determination of fascial defects. Discussion: Functional cine MRI of the pelvic floor is a promising new imaging method for the detection of organ descent and prolapse in patients with equivocal clinical findings. The combination of function and morphology allows for an innovative view of the pelvic floor, and thus adds to our understanding of the various interactions of the structures.

  1. SEM Investigation of Superheater Deposits from Biomass-Fired Boilers

    DEFF Research Database (Denmark)

    Jensen, Peter Arendt; Frandsen, Flemming; Hansen, Jørn

    2004-01-01

    , mature superheater deposit samples were extracted from two straw-fired boilers, Masnedø and Ensted, with fuel inputs of 33 MWth and 100 MWth, respectively. SEM (scanning electron microscopy) images and EDX (energy dispersive X-ray) analyses were performed on the deposit samples. Different strategies...

  2. SOURCE SAMPLING FINE PARTICULATE MATTER: WOOD-FIRED INDUSTRIAL BOILER

    Science.gov (United States)

    The report provides a profile for a wood-fired industrial boiler equipped with a multistage electrostatic precipitator control device. Along with the profile of emissions of fine particulate matter of aerodynamic diameter of 2.5 micrometers or less (PM-2.5), data are also provide...

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

    Science.gov (United States)

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

    2010-01-12

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

  4. The Boiler Room and Beyond: Bridging Standards and Community.

    Science.gov (United States)

    Active Learner: A Foxfire Journal for Teachers, 2000

    2000-01-01

    Mini-field trips to the boiler room and bus garage at a South Dakota elementary school increased student interest in their school and community and resulted in increased attendance. Photographs, interviews, and a student-produced book on the trips reinforced student interest and provided the means to integrate the curriculum and incorporate…

  5. Constrained control of a once-through boiler with recirculation

    DEFF Research Database (Denmark)

    Trangbæk, K

    2008-01-01

    There is an increasing need to operate power plants at low load for longer periods of time. When a once-through boiler operates at a sufficiently low load, recirculation is introduced, significantly altering the control structure. This paper illustrates the possibilities for using constrained con...

  6. 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...

  7. A burner for plasma-coal starting of a boiler

    Science.gov (United States)

    Peregudov, V. S.

    2008-04-01

    Advanced schemes of a plasma-coal burner with single-and two-stage chambers for thermochemical preparation of fuel are described. The factors causing it becoming contaminated with slag during oil-free starting of a boiler are considered, and methods for preventing this phenomenon are pointed out.

  8. A burner for plasma-coal starting of a boiler

    Energy Technology Data Exchange (ETDEWEB)

    V.S. Peregudov [Kutateladze Institute of Thermal Physics, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2008-04-15

    Advanced schemes of a plasma-coal burner with single-and two-stage chambers for thermochemical preparation of fuel are described. The factors causing it becoming contaminated with slag during oil-free starting of a boiler are considered, and methods for preventing this phenomenon are pointed out.

  9. 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...

  10. Oxygen pitting failure of a bagasse boiler tube

    CSIR Research Space (South Africa)

    Heyes, AM

    2001-04-01

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

  11. 30 CFR 77.411 - Compressed air and boilers; general.

    Science.gov (United States)

    2010-07-01

    ... Section 77.411 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND... standards and specifications of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code....

  12. Critical review of kraft recovery boiler air systems

    Energy Technology Data Exchange (ETDEWEB)

    Mac Callum, C.; Blackwell, B.R.

    1987-10-01

    Combustion air systems offered by major world suppliers of kraft recovery boilers are reviewed. A preliminary mathematical analysis of the air-jet trajectories in the furnace indicated that the conventional air systems leave room for improving the jet penetration into the furnace core. 9 refs., 2 figs., 1 tab.

  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. Assessment of pelvic floor dysfunctions using dynamic magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Hoda Salah Darwish

    2014-03-01

    Conclusion: Dynamic MRI is an ideal, non invasive technique which does not require patient preparation for evaluation of pelvic floor. It acts as one stop shop for diagnosing single or multiple pelvic compartment involvement in patients with pelvic floor dysfunction.

  15. Testing of the Anorectal and Pelvic Floor Area

    Science.gov (United States)

    ... Disorders of the Large Intestine Disorders of the Pelvic Floor Motility Testing Personal Stories Contact About GI Motility ... Disorders of the Large Intestine Disorders of the Pelvic Floor Motility Testing Personal Stories Contact Anorectal and Pelvic ...

  16. Floor Vibrations - as Induced and Reduced by Humans

    DEFF Research Database (Denmark)

    Pedersen, Lars

    . The appropriateness and accuracy of this modelling approach is evaluated. Implications of human-floor interaction are studied with focus on the impact of the interaction on the size of vibration levels of human-occupied floors and on the impact on floor dynamic characteristics. The influence of the interaction......The work is a contribution to the problem of modelling human-induced dynamic loads on floors and to the problem of modelling the interaction between stationary crowds of people and a vibrating floor. Experimental investigations are made to examine, update and refine currently available models....... As for dynamic loads focus is placed on heel impact excitation and actions of jumping people causing floor vibrations. As for interaction between stationary humans and the vibrating floor focus is on modelling humans as oscillating spring-mass-damper systems attached to the floor rather than as simple added mass...

  17. A novel & affordable interactive floor for educational applications

    DEFF Research Database (Denmark)

    Boisen, Ulrik; Hansen, Anders Juul; Knudsen, Lars

    2011-01-01

    This article examines two research areas: How interactive floors can be used beneficially in an educational context, and how an interactive floor can be created which is mobile and relatively inexpensive....

  18. Severe bleeding after sinus floor elevation using the transcrestal technique

    DEFF Research Database (Denmark)

    Jensen, Simon Storgard; Eriksen, Jacob; Schiodt, Morten

    2012-01-01

    To present a rare but clinically significant complication to sinus floor elevation (SFE) using the transcrestal technique.......To present a rare but clinically significant complication to sinus floor elevation (SFE) using the transcrestal technique....

  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. Biomass and waste gasification in pulverised coal-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Nieminen, M.; Kurkela, E.; Palonen, J. [VTT Processes, Espoo (Finland)

    2004-07-01

    The replacement of coal in existing large pulverised coal-fired boilers is a cost-effective way to lower the CO{sub 2} emissions of power production. A power plant concept consisting of a gasifier connected to a large conventional boiler with a high efficiency steam cycle offers an attractive and efficient way house local biomass and waste sources in energy production. In the simplified concept clean biomass or waste is gasifier and gas is directly fed to PC boiler and co-combusted with coal. At Kymijarvi power plant in Lahti, Finland, 60 MW circulating fluidized bed gasifier was commissioned in early 1998 and has since then been in commercial operation replacing hard coal in a 360 MW{sub th} boiler producing power and district heat. The annual gasifier availability has been over 95% in each year and the Lahti plant has clearly demonstrated that the technology is technically proven and is able to reduce the emission of CO{sub 2}, SO{sub 2}, dust and NOx compared to coal-alone combustion. Contaminated biomass or waste fuels can also be utilised for replacing coal in large-scale PC boiler but most of the harmful contaminants have to be removed prior co-combustion of the gas. Product gas cleaning makes it possible to utilise even fuels with higher chlorine and metal contents. The dry gas cleaning methods have been tested at pilot scale and will be soon demonstrated in gasification plants designed for solid recovered fuels originating form household and industrial wastes. 5 refs., 4 figs., 5 tabs.

  1. 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.

  2. Formaldehyde and TVOC emission behavior of laminate flooring by structure of laminate flooring and heating condition.

    Science.gov (United States)

    An, Jae-Yoon; Kim, Sumin; Kim, Hyun-Joong

    2011-03-15

    Formaldehyde was measured with a desiccator, a 20 L chamber and the FLEC method. The formaldehyde emission rate from laminate was the highest at 32 °C using the desiccator, which then decreased with time. The formaldehyde emission using the 20 L small chamber and FLEC showed a similar tendency. There was a strong correlation between the formaldehyde and total volatile organic compounds (TVOCs) with both types of floorings using the two different methods. The formaldehyde emission rate and TVOC results were higher when tested using the FLEC method than with the 20 L small chamber method. The emission rate was affected by the joint edge length in laminate flooring. Toluene, ethylbenzene and xylene were the main VOCs emitted from laminate flooring, and there were more unidentified VOCs emitted than identified VOCs. The samples heated with a floor heating system emitted more formaldehyde than those heated using an air circulation system due to the temperature difference between the bottom panel and flooring. The TVOC emission level of the samples was higher when an air circulation system was used than when a floor heating system was used due to the high ventilation rate.

  3. On the Construction of Building Project Monolith Floor%建筑工程整体地面的施工

    Institute of Scientific and Technical Information of China (English)

    邱国彬

    2011-01-01

    Monolith floor mainly refers to concrete floor, cement mortar floor, cast-in-site terrazzo floor and magnesite composition floor.This is a commonly used floor with the foundation layer and the cushion layer the same method, only the material used at surfacing and oonstruction method are different.A large part of the project with its foundation layer and cushion layer are completed at civil work, at the decoration project, only the surfacing layer is completed.In the practice, the cement mortar floor and cast-in-site terrazzo floor are commonly used.Therefore, the paper mainly discussed the construction process of these two floors.%整体地面主要是指混凝土地面、水泥砂浆地面、现浇水磨石地面和菱苦土地面等.这是一种应用较为广泛、具有传统做法的地面,其基层和垫层的做法相同,仅面层所用材料和施工方法有所区别.绝大部分工程的基层和垫层在土建工程中完成,在装饰工程中仅进行面层的施工.由于在实际工程中应用水泥砂浆地面和现浇水磨石地面较多,所以本文重点介绍这两种地面的施工工艺.

  4. Deflection of Resilient Materials for Reduction of Floor Impact Sound

    OpenAIRE

    Jung-Yoon Lee; Jong-Mun Kim

    2014-01-01

    Recently, many residents living in apartment buildings in Korea have been bothered by noise coming from the houses above. In order to reduce noise pollution, communities are increasingly imposing bylaws, including the limitation of floor impact sound, minimum thickness of floors, and floor soundproofing solutions. This research effort focused specifically on the deflection of resilient materials in the floor sound insulation systems of apartment houses. The experimental program involved condu...

  5. Knowledge of the pelvic floor in nulliparous women

    OpenAIRE

    Neels, Hedwig; Wyndaele, Jean-Jacques; Tjalma, Wiebren A. A.; De Wachter, Stefan; Wyndaele, Michel; Vermandel, Alexandra

    2016-01-01

    [Purpose] Proper pelvic floor function is important to avoid serious dysfunctions including incontinence, prolapse, and sexual problems. The current study evaluated the knowledge of young nulliparous women about their pelvic floor and identified what additional information they wanted. [Subjects and Methods] In this cross-sectional survey, a validated, 36 item questionnaire was distributed to 212 nulliparous women. The questionnaire addressed demography, pelvic floor muscles, pelvic floor dys...

  6. Recognition and Management of Nonrelaxing Pelvic Floor Dysfunction

    OpenAIRE

    Faubion, Stephanie S.; Shuster, Lynne T.; Bharucha, Adil E.

    2012-01-01

    Nonrelaxing pelvic floor dysfunction is not widely recognized. Unlike in pelvic floor disorders caused by relaxed muscles (eg, pelvic organ prolapse or urinary incontinence, both of which often are identified readily), women affected by nonrelaxing pelvic floor dysfunction may present with a broad range of nonspecific symptoms. These may include pain and problems with defecation, urination, and sexual function, which require relaxation and coordination of pelvic floor muscles and urinary and ...

  7. Complete Pelvic Floor Repair in Treating Fecal Incontinence

    OpenAIRE

    Lee, Patrick Y. H.; Steele, Scott R

    2005-01-01

    Fecal incontinence is associated with 20 to 40% of the patients with pelvic floor prolapse. Successful management of fecal incontinence requires not only an understanding of anorectal function but also a thorough understanding of pelvic floor anatomy and how pelvic floor prolapse affects fecal continence. Imaging techniques have been instrumental in visualizing pelvic floor prolapse and have helped correlate surgical findings. Stabilization of the perineal body appears to be a key component t...

  8. Deposit Formation during Coal-Straw Co-Combustion in a Utility PF-Boiler

    DEFF Research Database (Denmark)

    Andersen, Karin Hedebo

    1998-01-01

    observed, but can not represent the mature deposits satisfactorily. The chemical composition of the mature deposits indicate, that sulphate based consolidation is of importance in the deposit maturation.The chemical elements of primary interest in coal-straw co-combustion are K and Cl, which are both...... introduced with the straw was bonded as K-Al-silicate during combustion, and the remaining available K formed K2SO4, which could participate in deposit formation and consolidation. No significant participation of K was seen in the coal ash deposits, whereas K was a large contributor the up- and downstream.......In conclusion, this study has provided new knowledge on the effects of coal-straw co-combustion on fouling deposit formation in a full-scale PF-boiler, including an experimental and thermodynamic evaluation of the behaviour of elements originating from the straw in deposits and fly ash, and the limits...

  9. 锅炉微机控制设计与改进%Design and Improvement of Boiler Microcomputer Control Technology

    Institute of Scientific and Technical Information of China (English)

    李林

    2011-01-01

    The composition and function of boiler microcomputer, control design of fumace negative pressure and drum water level, improvement of feed system and fimctions and applications of monitor management system are introduced.%介绍锅炉微机控制系统的组成和功能,炉膛负压、汽包水位的控制设计,以及选料系统的改进,监控管理系统的功能及应用。

  10. What Do You Really Know About Floor Finishes & Strippers?

    Science.gov (United States)

    Wirth, T. J.

    1972-01-01

    An independent testing laboratory reveals the results of comparative studies done on vinyl flooring and the question of to wax or not to wax'' and which waxes work best with what flooring; and provides six evaluation tips on floor strippers. (EA)

  11. Pelvic floor function during and after first pregnancy

    NARCIS (Netherlands)

    Brummen, H.J. van

    2006-01-01

    This study evaluated the effects the first pregnancy and childbirth on the pelvic floor. Pregnancy and vaginal delivery can negatively affect pelvic floor function. Micturition symptoms, defecation symptoms and sexual dysfunction are all signs of an impaired pelvic floor function. These symptoms are

  12. Factors affecting the use of hardwood flooring in urban rehabilitation

    Science.gov (United States)

    Robert L. Jr. Nevel; Robert L. Jr. Nevel

    1973-01-01

    The continued use of hardwood flooring in urban rehabilitation is being threatened. A study of the influences that determine the choice of flooring indicates that economic, physical, or technological factors dominate. Most factors affecting the use of hardwood flooring are related to cost, availability, and compatibility. Of these factors, time and cost of installation...

  13. Slagging characteristics of molten coal ash on silicon-aluminum combustion liners of boiler

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In order to study the slagging characteristics of boiler combustion liners during pulverized coal stream combustion,the slag samples on the surface of combustion liner were investigated by X-ray diffractometry,scan electron microscopy and energy dispersive X-ray analysis,and the transformation characteristics of the compositions and crystal phases were studied.The results show that the size of slag granules decreases as the slagging temperature increases;the crystallinity of coal ash I reduces to about 48.6% when the temperature is increased up to 1 350 ℃,and that of the coal ash Ⅱ reduces to about 65% when the temperature is increased up to 1 500 ℃;the encroachment of molten coal ash to the combustion liner is strengthened.At the same time,the diffusion and the segregation of the compositions in combustion liners have selectivity,which is in favor of enhancing the content of crystal phases,weakening the conglutination among molten slag compositions and combustion liner,and avoiding yielding big clinkers.But the diffusion of the compositions in combustion liners increases the porosity and decreases the mechanical intensity of combustion liner,and makes the slag encroachment to the liner become more serious.

  14. RFID Data Cleaning for Shop Floor Applications

    Science.gov (United States)

    Ziekow, Holger; Ivantysynova, Lenka; Günter, Oliver

    In several case studies we found that shop-floor applications in manufacturing pose special challenges to cleaning RFID data. The underlying problem in many scenarios is the uncertainty about the exact location of observed RFID tags. Simple filter s provided in common middleware solutions do not cope well with these challenges. Therefore we have developed an approach based on maximum-likelihood estimation to infer a tag's location within the reader range. This enables improved RFID data cleaning in a number of application scenarios. We stress the benefits of our approach along exemplary application scenarios that we found in manufacturing. In simulations and experiments with real world data we show that our approach outperforms existing solutions. Our approach can extend RFID middleware or reader firmware, to improve the use of RFID in a range of shop-floor applications.

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

    Science.gov (United States)

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

    2016-02-01

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

  17. Concrete floor-bovine claw contact pressures related to floor roughness and deformation of the claw.

    Science.gov (United States)

    Franck, A; De Belie, N

    2006-08-01

    The intention of this research was to study the impact of concrete floor surface roughness on a bovine claw model and to assess the deformation of the bovine claw model under load. The pressure distribution between the floor and the claw is the key method in this research. Monitoring foot-to-ground pressure distributions may provide insight into the relation between high local pressures and foot lesions. Concrete floor samples were made with 5 different finishing methods. Their roughness was determined by measuring the heights of the "peaks and the valleys" of the surface with a high-precision laser beam. The smoothest surface was the sample finished with a metal float (surface roughness R(a) = 0.062 mm) and the roughest surface occurred with the heavily sandblasted sample (surface roughness R(a) = 0.488 mm). The roughness of the concrete floor samples was related to the mean and peak contact pressures that can occur in a laboratory test bench between floor and bovine claw. It was found that the claw itself has approximately 2 times more effect on these contact pressures than the surface roughness. Peak pressures found were high enough (up to 111 MPa) to cause damage to the bovine claw sole horn. The strains occurring in the horn wall were measured and related to the floor-finishing method and the load. Strain gauge measurements indicated that it is difficult to predict what kind of deformation of the claw wall will occur at a certain location. Different strains will occur for different floor-finishing methods. The corresponding stresses in the horn wall did not exceed the yield stress (14 and 11 MPa for dorsal and abaxial wall horn, respectively).

  18. Ocean floor mounting of wave energy converters

    Science.gov (United States)

    Siegel, Stefan G

    2015-01-20

    A system for mounting a set of wave energy converters in the ocean includes a pole attached to a floor of an ocean and a slider mounted on the pole in a manner that permits the slider to move vertically along the pole and rotate about the pole. The wave energy converters can then be mounted on the slider to allow adjustment of the depth and orientation of the wave energy converters.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-12-01

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

  20. The effect of fuel form on trace element emissions in an industrial-scale coal fired boiler

    Energy Technology Data Exchange (ETDEWEB)

    Miller, S.F.; Wincek, R.T.; Miller, B.G.; Scaroni, A.W. [Pennsylvania State Univ., University Park, PA (United States). Coal Utilization Lab.

    1998-12-31

    Eleven of the fourteen inorganic hazardous air pollutants identified in Title 3 of the Clean Air Act Amendments of 1990 are present in the flue gas of pulverized coal-fired boilers. The designated elements include: antimony (Sb), beryllium (Be), chlorine (Cl), cobalt (Co), manganese (Mn), nickel (Ni), selenium (Se), fluorine (F), arsenic (As), cadmium (Cd), chromium (Cr), lead (Pb), mercury (Hg), and phosphorus (P). Determining the risk of these elements in the environment is difficult at best. However, regulating their emission into the environment has some scientific basis and merit. Approximately 137.5 tons of mercury were emitted in the US by combustion sources in 1994--1995, with coal-fired utility boilers accounting for 37.4% (or 51.6 tons) of the total. Control of trace element emissions from coal-fired utility boilers requires an understanding of the manner in which they occur in coal, their behavior during and after combustion and their form in the stack gas. The multimedia behavior of trace elements during combustion can be traced to their volatility within the combustion and post-combustion environment. The temperature distribution within the combustion system, the mechanism of char and ash formation (e.g. duration of char burnout and char and cenosphere morphology) and the combustion efficiency determine the partitioning of trace elements during combustion. These factors can be affected by the form in which a fuel is fired, e.g., pulverized coal (PC) versus coal-water slurry fuel (CWSF). This paper presents preliminary results of emissions testing aimed at determining the effect of fuel form on the penetration and partitioning of trace elements in an industrial-scale boiler. The tests were conducted on a 2 MMBtu/hr research boiler, in which Middle Kittanning Seam coal (hvA bituminous) from Jefferson County, Pennsylvania was burned in pulverized form and as a CWSF. The tests were conducted in accordance with the procedure outlined in EPA Methods 5 and 29