WorldWideScience

Sample records for boiler corrosion technical

  1. 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.

  2. 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.

  3. 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.).

  4. 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).

  5. Low-cost Evaporator Protection Method against Corrosion in a Pulverized Coal Fired Boiler

    OpenAIRE

    Arkadiusz Krzysztof Dyjakon; Przemysław Bukowski

    2010-01-01

    Corrosion processes appearing on the watertubes in a combustion chamber of pulverized coal-fired boilers require permanent control and service. Subject to the power plant strategy, different anti-corrosion protection methods can be applied. Technical-economical analysis has been performed to evaluate and support the decisions on maintenance and operation services. The paper presents and discusses results of the application of an air protection system in boiler OP-230 in view of anti-corrosion...

  6. Model boiler studies on deposition and corrosion

    International Nuclear Information System (INIS)

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

  7. 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.

  8. Aspects of high temperature corrosion of boiler tubes

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-01

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

  9. Corrosion probes for fireside monitoring in coal-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Covino, Bernard S., Jr.; Bullard, Sophie J.; Ziomek-Moroz, M.; Holcomb, Gordon R.

    2005-01-01

    Corrosion probes are being developed and combined with an existing measurement technology to provide a tool for assessing the extent of corrosion of metallic materials on the fireside in coal-fired boilers. The successful development of this technology will provide power plant operators the ability to (1) accurately monitor metal loss in critical regions of the boiler, such as waterwalls, superheaters, and reheaters; and (2) use corrosion rates as process variables. In the former, corrosion data could be used to schedule maintenance periods and in the later, processes can be altered to decrease corrosion rates. The research approach involves laboratory research in simulated environments that will lead to field tests of corrosion probes in coal-fired boilers. Laboratory research has already shown that electrochemically-measured corrosion rates for ash-covered metals are similar to actual mass loss corrosion rates. Electrochemical tests conducted using a potentiostat show the corrosion reaction of ash-covered probes at 500?C to be electrochemical in nature. Corrosion rates measured are similar to those from an automated corrosion monitoring system. Tests of corrosion probes made with mild steel, 304L stainless steel (SS), and 316L SS sensors showed that corrosion of the sensors in a very aggressive incinerator ash was controlled by the ash and not by the alloy content. Corrosion rates in nitrogen atmospheres tended to decrease slowly with time. The addition of oxygen-containing gases, oxygen and carbon dioxide to nitrogen caused a more rapid decrease in corrosion rate, while the addition of water vapor increased the corrosion rate.

  10. 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...

  11. Low-cost Evaporator Protection Method against Corrosion in a Pulverized Coal Fired Boiler

    Directory of Open Access Journals (Sweden)

    Arkadiusz Krzysztof Dyjakon

    2010-07-01

    Full Text Available Corrosion processes appearing on the watertubes in a combustion chamber of pulverized coal-fired boilers require permanent control and service. Subject to the power plant strategy, different anti-corrosion protection methods can be applied. Technical-economical analysis has been performed to evaluate and support the decisions on maintenance and operation services. The paper presents and discusses results of the application of an air protection system in boiler OP-230 in view of anti-corrosion measures. It is indicated that a low-cost protection method of watertubes (evaporator against corrosion can be efficient and lead to financial savings in comparison to the standard procedure of replacement of watertube panels.

  12. Boiler tube corrosion characterization with a scanning thermal line

    Science.gov (United States)

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

    2001-03-01

    Wall thinning due to corrosion in utility boiler waterwall 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 waterwalls.

  13. Managing corrosion in biomass boilers. Benefits and limitations of coatings

    Energy Technology Data Exchange (ETDEWEB)

    Tuurna, S.; Varis, T.; Ruusuvuori, K. (and others) (VTT Technical Research Centre of Finland, Espoo (Finland))

    2010-05-15

    Oxidation and corrosion of materials in highly demanding applications is critical for longterm performance of materials used in power generation. Energy production in biomass fired boilers is increasing rapidly due to the advantages of CO{sub 2} neutrality and renewability. Fluidised bed combustors and grate fired boilers have proved the most reliable technologies for burning biomass since its fuel characteristics are variable. The fly ash of biomass is relatively corrosive due to its composition containing high concentrations of chemically active compounds of alkali, sulphur and chlorine, and it also may contain erosive components especially in the case of fluidised bed boilers. Due to the potential for severe chlorine induced corrosion, plant operating temperatures and efficiency must be limited. To overcome material wastage more alloyed materials are needed. The high cost and sometimes hard to manufacture bulk materials could be replaced with coatings, which can be applied on the more economic low alloy steel having the proper mechanical properties. The paper discusses the benefits and limitations of thermal sprayed coatings in biomass boilers. The applied examples have included iron and nickel based HVOF and arc sprayed coatings subjected to verification field testing in boiler testing under in aggressive biofuel conditions. The coatings have shown good corrosion resistance in long-term field tests. (orig.)

  14. 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.

  15. Hot Corrosion Studies in Coal Fired Boiler Environment

    Directory of Open Access Journals (Sweden)

    Kamal Subhash

    2014-07-01

    Full Text Available Hot corrosion behaviour of the bare and D-gun coated superfer 800H exposed to low temperature super-heater zone of the coal fired boiler of Guru Nanak Dev Thermal Power Plant, Bathinda, Punjab, India. The specimens were hanged in the platen super-heater of coal fired boiler where the gas temperature was around 900 °C ±10 °C. Hot corrosion experiments were performed for 10 cycles, each cycle consisting of 100 hours exposure followed by 1 hour cooling at ambient temperature. Weight change measurements were done at the end of each cycle. The weight change data used for predicting hot corrosion behaviour of the coated alloys after the total exposure of 1000 hours. The different phases and their distribution in the hot corroded specimens were analysed with the help of FE-SEM/EDS and X-ray mapping.

  16. 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

  17. Corrosion of evaporator tubes in low emission steam boilers

    Directory of Open Access Journals (Sweden)

    S. Topolska

    2010-04-01

    Full Text Available Purpose: of this paper is to reveal the mechanisms of corrosion processes of outer surfaces of low-emission steam boiler evaporator tubes. Examinations were performed to find the reasons of different corrosion susceptibility of tubes situated at combustion chamber on various levels.Design/methodology/approach: Examinations were conducted on several segments of Ø 57 x 5.0 mm evaporator tubes made of 16M (16Mo3 steel grade. Segments were taken from level of 10 meters and 18 meters from the chamber bottom of low-emission coal fired steam boiler after two years operation. Microstructure degradation of base material was estimated. Metallographic evaluation of scale morphology, its micro sites chemical composition analysis and distribution of elements on cross sections have been performed.Findings: Eexaminations of evaporator tubes indicated that reduction of wall thickness was considerable at the segments taken from level of 10 m, when at level of 18 m this reduction was small. The morphology of scales consisted of external layer which was porous and weakly connected to the tube surface, and internal layer, which was dense and adherent to the base metal. In these two layers the bands reach in sulfur were detected. The sulfide corrosion seems to be the main degradation mechanism of the tube surface at the level of 10 m.Research limitations/implications: Corrosion of the water wall tubes in low-emission steam boilers is a result of reaction of steel tube surface with the aggressive substoichiometric environment contains sulfur. The chemical composition of flue gases changes along the water wall. The exact compound of flue gases has not been determined in this study.Practical implications: Prevention of water wall tubes corrosion can be achieved by changing in operation conditions or replacement of tube materials. The first mentioned action is limited to accurate burner’s adjustment or introduces a flow of additional air along the walls and create

  18. On-line monitoring and control of furnace wall corrosion in pf-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Farrell, D.M.; Robbins, B.J.; Sikka, P.; Seaman, M. [Rowan Technologies Ltd., Manchester (United Kingdom)

    2004-05-15

    Corrosion, fouling and sometimes failure of heat exchanger tubing that makes up the boiler walls is a major obstacle to minimising boiler downtime. Rowan Technologies Ltd., has been developing corrosion scanners to enable the condition of these heat exchanger tubes to be assessed online. These scanners are able to monitor fireside corrosion over entire boiler walls and whilst the boiler is operational. This paper describes how the scanner systems can be used to monitor this corrosion and how the corrosion can be subsequently controlled. 8 refs., 9 figs.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-03-15

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

  20. Untypical bromine corrosion in boilers co-firing biomass

    Directory of Open Access Journals (Sweden)

    A. Hernas

    2012-09-01

    Full Text Available Purpose: The aim of this study was to determine the untypical corrosion resistance of rotary air preheaters in a biomass co-fired power plant.Design/methodology/approach: The selected results of some components of regenerative rotary air preheaters in a biomass co-fired power plant are presented. The macro and microstructure of corroded components of a LUVO preheater after 3 years of service are presented. The chemical composition of corrosion products was determined by X-ray microanalysis.Findings: Data concerning toxicity and identification of PBDEs (Polibrominated diphenyl ethers in the biomass is very limited. The presented research provides information and the proposed corrosion reaction mechanism in environments containing biomass with aggressive compounds like Cl, Si, H and Br.Research limitations/implications: An extended research on PBDEs in power plant fuels is necessary to give a full assessment of the corrosion mechanism in the presented environment; obligatory classification of the co-fired biomass.Originality/value: Firstly, an assessment of the danger for boiler materials co-firing biomass containing brominated organic flame and presentation of the reaction during the corrosion process and degradation of power boiler components in the presented environment. Secondly, the highlighting of the problem that there is a need to properly select and determine the chemical composition of the biomass used.

  1. Low temperature corrosion in bark fuelled, small boilers

    Energy Technology Data Exchange (ETDEWEB)

    Lindau, Leif; Goldschmidt, Barbara

    2008-05-15

    A number of small (3-12 MW), new biofuel boiler plants in southern Sweden, and (at least) in Austria, have suffered a high (wastage of mm/yrs) corrosion rate on the low temperature boiler side. This problem has been investigated with respect to its occurrence and its character by contacts with operators, by plant inspections, and by analysis of cold-side deposits. The plants affected have low feed water temperatures (< 100 deg C). The plants fire most types of Swedish biofuel: chips, bark, hog fuel, and 'GROT' (=twigs and tops). The results found give basis for a hypothesis that the corrosion results from the presence of an aqueous phase in the deposits, this phase being stabilized by dissolved salts having high solubility. It then follows that for each salt, there is a critical relative humidity (calculated from the flue gas water partial pressure and the cooling surface temperature as is common practice among boiler engineers) for both the presence of the aqueous phase and the corrosion. Some critical single salts, ZnCl{sub 2} and CaCl{sub 2} have been identified, and they give critical 'relative humidities' of 5% and 18% respectively. These figures are a lower bound. The corresponding figure, derived from the practical experience and the reported plant operational data, is between 20 and 30%. Corrosion tests have been carried out by exposing an air-cooled probe in the flue gases at a 12 MW boiler at Saevelundsverket in Alingsaas, and the material wastage at different temperatures has been measured with a profilometer. The high corrosion rates were reproduced in the tests for high relative humidities. The corrosion rate was small and not measurable (<0.1 mm/year) for relative humidity <22%. The work shows by means of indirect evidence that the corrosion critical components are ZnCl{sub 2} and possibly CaCl{sub 2} as well. The practical engineering design criterion derived from the work is that the relative humidity (calculated from the flue

  2. Superheater corrosion in kraft recovery boilers; Korrosion hos oeverhettare i sodapannor. En oeversikt och diskussion

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, F. [AaF-IPK, Stockholm (Sweden)

    1997-02-01

    Corrosion seems to be the most essential factor limiting the life and the availability of kraft recovery boilers. The steam temperature from the kraft recovery boiler has, seen from the view of electricity production and steam turbine operation, traditionally been kept moderate, especially in comparison with steam data from normal utility power plants. So the corrosion of the superheaters has been more a limitation for the temperature of the steam produced by the boiler than a life length limitation. Both the pressure and the temperature of the steam are limited by corrosion. The temperature of the boiling water, and hence the pressure, is limited by the corrosion in the lower furnace. The temperature of the steam is limited by the corrosion in the superheater. Kraft boiler superheater corrosion is here governed not only by the boiler design, but more by the mill chemistry and boiler operation practice. This report discusses the formation and the properties of the deposits and their relation to boiler operation and the corrosion of the superheater tube material. We have tried to understand the corrosion in the kraft boiler superheaters better by comparing with the experience from the utility boilers. 86 refs, 79 figs

  3. 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.

  4. 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.

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

    International Nuclear Information System (INIS)

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

  6. Deposition and High-Temperature Corrosion in Biomass-Fired Boilers

    DEFF Research Database (Denmark)

    Michelsen, Hanne Philbert

    This thesis describes the fate of potassium, chlorine, and sulfur in regard to deposition and corrosion problems in straw-fired boilers. Full-scale deposition studies at Rudkøbing CHP, Kyndby Power Station and Masnedø CHP revealed that straw may form massive deposits in the convective pass...... has only been detected in insignificant amounts in mature deposits in straw-fired boilers formed over months of operation.The corrosion of superheater tubes is closely connected to the material which are deposited on the surface and deposits containing potassium chloride can cause severe high......-temperature corrosion at elevated metal temperatures. Lab-scale corrosion experiments, where metal test elements were covered with synthetic potassium salts and real deposits and exposed to a simulated flue gas containing HCl(g) and SO2(g), provided information about the corrosion rate and corrosion mechanisms...

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

    Science.gov (United States)

    Ghosh, Debashis; Mitra, Swapan Kumar

    2011-04-01

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

  8. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, William (Sandy) [SharpConsultant

    2011-12-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Koebel, M.; Elsener, M.

    1987-01-01

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

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

    Science.gov (United States)

    Yang, Dong

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

  12. Development of an electrochemistry-based corrosion sensor to monitor corrosion of boiler tubes, pipes, and painted structures

    Science.gov (United States)

    Davis, Guy D.; Dacres, C. M.; Shook, M. B.

    1998-03-01

    An electrochemical impedance spectroscopy (EIS)-based in-situ corrosion sensor has been adapted and evaluated for use with steel heat exchanger tubes in boilers, coated buried steel pipes, and painted steel structures. An excellent correlation was obtained between the algorithm of the ratio of the breakpoint frequencies, as measured by the sensor, and corrosion rate for the boiler tubes. Use of this sensor and appropriate electronics would allow the corrosion of the boiler tubes to be monitored in real time and the inhibitor concentration automatically controlled to prevent excessive corrosion. The EIS sensor is also sensitive to the quality of coating of a buried steel pipe with and without the application of cathodic protection. Similar results were obtained from a sensor attached to the pipe and from a separate electrode driven into the soil. A hand-held version of the EIS in-situ sensor is suitable for inspecting painted metal structures, such as storage tanks and locks and dams, under ambient, service conditions. An excellent correlation was obtained between the sensor measurements, and the amount of corrosion on test panels immersed for up to 28 years.

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

    Directory of Open Access Journals (Sweden)

    Edori, E. S

    2016-08-01

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

  14. Corrosion in waste-fired boilers: A thermodynamic study

    DEFF Research Database (Denmark)

    Becidan, Michael; Sørum, Lars; Frandsen, Flemming;

    2009-01-01

    A twofold study using thermodynamic equilibrium calculations was carried out to study corrosion in MSW incinerators. Corrosion was associated with the amount of alkalis and trace metals gaseous chlorides. Firstly, a two-level factorial experimental design combined with a data analysis were used...... corrosion-fighting additives (ammonium sulphate and silica) was investigated. Calculations confirmed experimental results and brought further insight on differentiated results for Na, K, Pb and Zn but also on capture mechanisms....

  15. Operation corrosion test of austenitic steel bends for supercritical coal boilers

    Directory of Open Access Journals (Sweden)

    Cizner J.

    2016-03-01

    Full Text Available Corrosion tests of both annealed and not annealed bends of HR3C and S304H steels in operation conditions of black and brown coal combustion boilers in EPRU and EDE. After a long-term exposure, the samples were assessed gravimetrically and metallographically. The comparison of annealed and unannealed states showed higher corrosion rates in the annealed state; corrosion of the sample surface did not essentially differ for compression and tensile parts of the beams. Detailed assessment of both steels is described in detail in this study.

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

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, William (Sandy) [SharpConsultant

    2011-12-01

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

  17. Formation of corrosion products protecting surfaces of the boiler proper tubes from the combustion chamber

    OpenAIRE

    Pietrzyk, M.; S. Król

    2007-01-01

    Purpose: The aim of this paper is to determine how the oxidation product layer of the steel applied for the radiant tubes should increase if we are going to obtain the lowest possible corrosion losses.Design/methodology/approach: Boiler tubes, made of 13CrMo4-5 steel were subjected to tests. In the boiler BP-1150, the tubes ø 30 x 5 mm are joined by fins and form a membrane shield. According to the maps of tube wall thickness, in the zone of the highest heat load, sectors of the shield were s...

  18. High-Temperature Corrosion of Protective Coatings for Boiler Tubes in Thermal Power Plants

    Institute of Scientific and Technical Information of China (English)

    XU Lianyong; JING Hongyang; HUO Lixing

    2005-01-01

    High-temperature corrosion is a serious problem for the water-wall tubes of boilers used in thermal power plants. Oxidation, sulfidation and molten salt corrosion are main corrosion ways.Thereinto, the most severe corrosion occurs in molten salt corrosion environment. Materials rich in oxides formers, such as chromium and aluminum, are needed to resist corrosion in high-temperature and corrosive environment, but processability of such bulk alloys is very limited. High velocity electric arc spraying (HVAS) technology is adopted to produce coatings with high corrosion resistance. By comparison, NiCr (Ni-45Cr-4Ti) is recommended as a promising alloy coating for the water-wall tubes, which can even resist molten salt corrosion attack. In the study of corrosion mechanism, the modern material analysis methods, such as scanning electron microscopy (SEM), X-ray diffractometry (XRD) and energy dispersive spectrometry (EDS), are used. It is found that the corrosion resistances of NiCr and FeCrAI coatings are much better than that of 20g steel, that the NiCr coatings have the best anti-corrosion properties, and that the NiCr coatings have slightly lower pores than FeCrAI coatings.It is testified that corrosion resistance of coatings is mainly determined by chromium content, and the microstructure of a coating is as important as the chemical composition of the material. In addition, the fracture mechanisms of coatings in the cycle of heating and cooling are put forward. The difference of the thermal physical properties between coatings and base metals results in the thermal stress inside the coatings. Consequently, the coatings spall from the base metal.

  19. Corrosion probes for fireside monitoring in coal-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    Covino, Bernard S., Jr.; Bullard, Sophie J.; Cramer, Stephen D.; Holcomb, Gordon R.; Ziomek-Moroz, Margaret; Eden, David A. (Intercorr International Inc.); Cayard, Michael S. (Intercorr International Inc.)

    2004-01-01

    Electrochemical corrosion rate (ECR) probes were constructed and exposed along with mass loss coupons in a N2/O2/CO2/H2O environment to determine ECR probe operating characteristics. Temperatures ranged from 450 to 600 C and both ECR probes and mass loss coupons were coated with ash. Results are presented in terms of the probe response to temperature, the measured zero baseline, and the quantitative nature of the probes. The effect of Stern-Geary constant and the choice of electrochemical technique used to measure the corrosion rate are also discussed. ECR probe corrosion rates were a function of time, temperature, and process environment and were found to be quantitative for some test conditions. Measured Stern-Geary constants averaged 0.0141 V/decade and the linear polarization technique was found to be more quantitative than the electrochemical noise technique.

  20. Application of High Temperature Corrosion-Resistant Materials and Coatings Under Severe Corrosive Environment in Waste-to-Energy Boilers

    Science.gov (United States)

    Kawahara, Yuuzou

    2007-06-01

    Corrosion-resistant materials (CRMs) and coatings are key technologies to increase power generation efficiency and reduce maintenance in waste-to-energy (WTE) plants. Corrosion environment became severe as steam temperatures have increased. The steam condition of more than 400 °C/3.9 MPa became possible in WTE boilers by using highly durable corrosion-resistant coatings, such as thermal spray of Al/80Ni20Cr alloy, HVOF-sprayed NiCrSiB alloy, Alloy 625 weld overlay for waterwall tubes and also superheater tubes. Also, the use of 310S type stainless steels and high Cr-high Mo-Ni base and high Si-Cr-Ni-Fe alloys have progressed because of a better understanding of corrosion mechanisms. Furthermore, high durability coatings using cermet and ceramic materials were applied to high temperature superheaters. This paper describes the major developments and the application of CRMs and coating technologies in the last 30 years in WTE plants, the corrosion mechanisms of alloys, the deterioration mechanisms of spray coating layers, and future subjects for the development of corrosion-resistant materials and coatings.

  1. Influence of Deposit Formation on Corrosion at a Straw Fired boiler

    DEFF Research Database (Denmark)

    Hansen, Lone Aslaug; Michelsen, Hanne Philbert; Frandsen, Flemming;

    2000-01-01

    Straw-fired boilers generally experience severe problems with deposit formation and are expected to suffer from severe superheater corrosion at high steam temperatures due to the large alkali and chlorine content in straw. In this study, deposits collected (1) on air-cooled probes and (2) directly...... at the existing heat transfer surfaces of a straw-fired boiler have been examined. Deposits collected on air-cooled probes were found to consist of an inner layer of KCl and an outer layer of sintered fly ash. Ash deposits formed on the heat transfer surfaces all had a characteristic layered structure...... composition on the corrosion of the superheaters is provided. (C) 2000 Elsevier Science B.V. All rights reserved....

  2. Boiler and steam generator corrosion. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    The bibliography contains citations concerning corrosion effects, mechanisms, detection, and inhibition in fossil fuel fired boilers and nuclear powered steam generators. Corrosion studies performed on the water side and hot gas side of heat exchanger tubes and support structures are presented. Water treatment, chemical cleaning, and descaling methods are considered. Although emphasis is placed on large-scale power generation systems, residential and commercial heating systems are also discussed. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  3. Low temperature corrosion in bark fuelled, small boilers; Laagtemperaturkorrosion i barkeldade, mindre pannor

    Energy Technology Data Exchange (ETDEWEB)

    Lindau, Leif; Goldschmidt, Barbara [Sycon Energikonsult AB, Malmoe (Sweden)

    2002-04-01

    A number of small (3-12 MW), new biofuel boiler plants in South Sweden, and (at least) in Austria, have suffered a high (wastage of mm/yrs.) corrosion rate on the low temperature boiler side. This problem has been investigated with respect to its occurrence and its character by contacts with operators, by plant inspections, and by analysis of cold side deposits. The plants affected have low feed water temperatures (< 100 deg C ). The plants fire most types of Swedish biofuel: chips, bark, hog fuel, and 'GROT'(=twigs and tops). The results found give basis for a hypothesis that the corrosion results from the presence of an aqueous phase in the deposits, this phase being stabilized by dissolved salts having high solubility. It then follows that for each salt, there is a critical relative humidity (calculated from the flue gas water partial pressure and the cooling surface temperature as is common practice among boiler engineers) for both the presence of the aqueous phase and the corrosion. Some critical single salts, ZnC12 and CaC12 have been identified, and they give critical 'relative humidities' of 5% and 18% respectively. These figures are a lower bound. The corresponding figure, derived from the practical experience and the reported plant operational data, is between 20 and 30%. Corrosion tests have been carried out by exposing an air-cooled probe in the fluegases at a 12 MW boiler at Saevelundsverket in Alingsaas, and the material wastage at different temperatures has been measured with a profilometer. The high corrosion rates were reproduced in the tests for high relative humidities. The corrosion rate was small and not measurable (<0.1 mm/yr) for relative humidity < 22%. The work shows by means of indirect evidence that the corrosion critical components are ZnCl{sub 2} and possibly CaCl{sub 2} as well. The practical engineering design criterion derived from the work is that the relative humidity (calculated from the flue gas water partial

  4. The Hot Corrosion Performance of NiCr-Cr3 C2 Cermet Coating to Boiler Tube

    Institute of Scientific and Technical Information of China (English)

    DINGZhang-xiong; TUGuo-fu

    2004-01-01

    Three kinds of NiCr-Cr3 C2 cermet coatings were designed and deposited by the subsonic velocity flame spraying, and their performances of hot corrosion performance were evaluated in comt)arison with 102G,20G boiler tube steel, FeCrAl, NiCrTi, Ni5OCr and NiCrAIMoFe-Cr3 C2 coatings, which are widely used at present for protection of boiler tubes. Meanwhile, the influence of sealer on the hot corrosion resistance of warious coatings and the mechanisms of coating corrosion were explored.

  5. Detailed investigation of Cl-corrosion initiated by deposits formed in biomass-fired boilers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, Flemming J.; Lith, S. van

    2009-10-15

    The aim was to investigate deposit-induced Cl-corrosion under well-controlled laboratory conditions, simulating the conditions in biomass-fired boilers. This has been done by exposing pieces of superheater tubes, covered by synthetic salts, at temperatures and gas mixtures simulating biomass-fired conditions. The corroded specimens have been studied in detail using a Scanning Electron Microscope (SEM), in order to determine the corrosion rate, and to investigate the chemistry and morphology of the corrosive attack. The project has been divided into four activities: A1: Relationship between the Cl-concentration in the deposit, and the corrosion rate. A2: Influence of cation type (K+ and Na+) on the mobility of Cl in the deposit. A3: Influence of metal temperature on the corrosion rate. A4: Critical evaluation of the existing experience for minimizing corrosion in full-scale boilers firing totally or partly with biomass. (LN)

  6. 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

  7. Boiler and steam generator corrosion: Fossil fuel power plants. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    The bibliography contains citations concerning corrosion effects, mechanisms, detection, and inhibition in fossil fuel fired boilers. Fluidized bed combustors and coal gasification are included in the applications. The citations examine hot corrosion, thermal mechanical degradation, and intergranular oxidation corrosion studies performed on the water side and hot gas side of heat exchanger tubes and support structures. Coatings and treatment of material to inhibit corrosion are discussed. Corrosion affecting nuclear powered steam generators is examined in a separate bibliography. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

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

    International Nuclear Information System (INIS)

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

  9. 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.

  10. Thermal Nondestructive Characterization of Corrosion in Boiler Tubes by Application fo a Moving Line Heat Source

    Science.gov (United States)

    Cramer, K. Elliott; Winfree, William P.

    2000-01-01

    Wall thinning in utility boiler waterwall tubing is a significant inspection concern for boiler operators. Historically, conventional ultrasonics has been used lor inspection of these tubes. This technique has proved to be very labor intensive and slow. This has resulted in a "spot check" approach to inspections, making thickness measurements over a relatively small percentage of the total boiler wall area. NASA Langley Research Center has developed a thermal NDE technique designed to image and quantitatively characterize the amount of material thinning present in steel 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 this analysis technique, represents a significant improvement in the inspection speed for large structures such as boiler waterwalls while still providing high-resolution thickness measurements. A theoretical basis for the technique will be presented thus demonstrating the quantitative nature of the technique. Further, results of laboratory experiments on flat Panel specimens with fabricated material loss regions will be presented.

  11. 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.

  12. Formation of corrosion products protecting surfaces of the boiler proper tubes from the combustion chamber

    Directory of Open Access Journals (Sweden)

    M. Pietrzyk

    2007-04-01

    Full Text Available Purpose: The aim of this paper is to determine how the oxidation product layer of the steel applied for the radiant tubes should increase if we are going to obtain the lowest possible corrosion losses.Design/methodology/approach: Boiler tubes, made of 13CrMo4-5 steel were subjected to tests. In the boiler BP-1150, the tubes ø 30 x 5 mm are joined by fins and form a membrane shield. According to the maps of tube wall thickness, in the zone of the highest heat load, sectors of the shield were sampled in the places where the tube wall thickness was equal or greater than 4.3 mm, i.e. the minimum calculation thickness, according to the specifications given by the boiler manufacturer. It means that the corrosive loss could be determined as small, in spite of a long operation time (more than 60,000 hours.Findings: The authors have determined structure and chemical and phase compositions of products and deposits forming in the radiant tubes in the regions of low corrosive losses after long-lasting operation (up to 60,000 hours. Then, they discussed a mechanism of formation of a compact layer protecting a steel surface against excessive oxidation under combustion gases.Practical implications: The layer on the tubes with small losses of wall thickness are characterized by the following properties: good compactness, very good adhesion to the metallic base, low amount of sulfur, especially in magnetite, no aggressive components at the phase boundary product – steel, small development of the phase boundary product-steel. Owing to those properties, even presence of sulfur in the products do not reduce their passivation qualities.Originality/value: Determination of the oxidation product layer of the steel applied for the radiant tubes.

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

    DEFF Research Database (Denmark)

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

    2010-01-01

    A relatively low electrical efficiency of 20−25% is obtained in typical west European waste boilers. Ash species released from the grate combustion zone form boiler deposits with high concentrations of Cl, Na, K, Zn, Pb, and S that cause corrosion of superheater tubes at high temperature...... that the waste grate combustion process can provide a flue gas with a high energy content and a relatively low concentration of corrosive species. This opens up for the possibility of using an additional superheater section to increase the steam temperature and, thereby, increase electrical efficiency........ The superheater steam temperature has to be limited to around 425 °C, and thereby, the electrical efficiency remains low compared to wood or coal-fired boilers. If a separate part of the flue gas from the grate has a low content of corrosive species, it may be used to superheat steam to a higher temperature...

  14. TRD, technical codes and instructions on steam boilers

    International Nuclear Information System (INIS)

    Condensed edition informing about layout and applications of the TRDs, materials, manufacture and dimensioning, calculations, equipment and installation, testing and operation, and boilers of groups I, II and III. (DG)

  15. Technical note 4. Corrosion of copper canister

    International Nuclear Information System (INIS)

    Objectives of the project: In this review assignment, SKB's treatment of copper corrosion processes or mechanisms in SR-Site shall be reviewed both for the anticipated oxic and anoxic repository environments. The reviewer(s) shall consider if corrosion and corrosion mechanisms of the copper canisters in different possible evolutionary repository environments have been properly described. The objectives of this initial review phase in the area of copper corrosion is to achieve a broad coverage of SR-Site and its supporting references and in particular identify the need for complementary information and clarifications to be delivered by SKB. Summary by the authors: It is expected that the inflow of ground water to the deposition holes and tunnels in the Forsmark repository will be very slow. Thus, it might take some few hundred years up to thousand years before the deposition holes are filled with ground water and it might take 6000 years or more before the bentonite buffer is fully water saturated and pressurized. The copper canisters will therefore meet to two completely different environments: 1. An initial period of several hundreds of years when copper is exposed to gaseous corrosion. 2. And then to aqueous corrosion. From a corrosion point of view the first 1000 years are the most critical for the copper canister since pure, or phosphorus alloyed copper, is not designed to cope with corrosion at elevated temperatures. The outer copper surface temperature is expected to reach 100 deg C within some decades after closure of the repository and then slowly cool down to around 50 deg C after 1000 years. The gaseous corrosion is treated in SKB's safety assessment as being only dependent on oxygen gas and thus easily estimated by an oxygen mass-balance calculation. This simple model has no scientific support since several corrosive trace gases, such as sulphurous and nitrous compounds, operates together with water molecules (moisture) and the corrosion product consists

  16. Development of Erosion-Corrosion-Resistant Cold-Spray Nanostructured Ni-20Cr Coating for Coal-Fired Boiler Applications

    Science.gov (United States)

    Kumar, M.; Singh, H.; Singh, N.; Chavan, N. M.; Kumar, S.; Joshi, S. V.

    2015-12-01

    The erosion-corrosion (E-C) behavior of a cold-spray nanostructured Ni-20Cr coating was studied under cyclic conditions in a coal-fired boiler. This study was done for 15 cycles (1500 h), in which each cycle comprised 100 h of heating in the boiler environment, followed by 1 h of cooling under ambient air conditions. The E-C extent was evaluated in terms of thickness loss data of the samples. The eroded-corroded samples were characterized using XRD, SEM/EDS, and x-ray mapping analyses. The nanostructured coating offered excellent E-C protection to boiler tube material (SA 516 steel) under harsh live conditions of the boiler. This E-C resistance offered by investigated coating may be attributed to the presence of protective NiO and Cr2O3 phases in its oxide scale and its superior as-sprayed microhardness.

  17. High temperature corrosion in a biomass-fired power boiler : Reducing furnace wall corrosion in a waste wood-fired power plant with advanced steam data

    OpenAIRE

    Alipour, Yousef

    2013-01-01

    The use of waste (or recycled) wood as a fuel in heat and power stations is becoming more widespread in Sweden (and Europe), because it is CO2 neutral with a lower cost than forest fuel. However, it is a heterogeneous fuel with a high amount of chlorine, alkali and heavy metals which causes more corrosion than fossil fuels or forest fuel. A part of the boiler which is subjected to a high corrosion risk is the furnace wall (or waterwall) which is formed of tubes welded together. Waterwalls are...

  18. Hot Corrosion Behaviour of Detonation Gun Sprayed Stellite-6 and Stellite-21 Coating on Boiler Steel SAE 431 at 900°C

    OpenAIRE

    N. K. Mishra; Rai, A K; S. B. Mishra; Kumar, R.

    2014-01-01

    Hot corrosion is the serious problem in gas turbines, superheaters, and economizers of coal-fired boilers. It occurs due to the usage of wide range of fuels such as coal, oil, and so on at the elevated temperatures. Protective coatings on boiler steels are used under such environments. In the present investigation, Stellite-6 and Stellite-21 coatings have been deposited on boiler steel SAE 431 by detonation gun method. The hot corrosion performance of Stellite-6 and Stellite-21 coated as well...

  19. Technical overview on FW-CFB boiler technology burning refuse derived fuel

    International Nuclear Information System (INIS)

    Municipalities in towns and cities across U.S. and in other developed countries are urgently seeking solutions for the disposal of municipal solid waste (MSW). This is because landfill sites are rapidly becoming inundated. Many of these municipalities are considering various methods to incinerate the wastes efficiently and cleanly while recovering energy. Municipal wastes vary greatly in size and composition, depending on the town, city or country where it is generated. Incinerating MSW directly requires complex combustion systems which include a moving or travelling grate furnace, stoker boiler or rotary kiln incinerator. These combustion systems have many moving parts and bum at an elevated furnace temperature that often result in a high furnace corrosion rate, frequent equipment failures and low plant availability. Additionally, they produce flue gas with high emissions of pollutants requiring expensive back end emission control systems. An alternate to incineration is to transform MSW to refuse derived fuel (RDF) and burn it in a fluidized bed boiler

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

    Science.gov (United States)

    Bales, Maurice J.; Bishop, Chip C.

    1995-05-01

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

  1. Investigation and analysis of high temperature corrosion and degradation of marine boiler combustion swirler

    Science.gov (United States)

    Virdi, R. S.; Thakur, D. G.

    2016-03-01

    The present paper investigated and analyzed swirler material consisting of mild steel which was subjected to service for the period of one year in a 30 MW marine boiler. Due to the presence of high temperatures in the furnace coupled with the corrosive marine environment swirler material showed accelerated degradation and material wastage. An investigation into the feasibility of manufacturing the existing swirler with an alternate material or coating the swirler material with a thermal barrier coating was undertaken. Based on their properties and performance, SS 304 and SS 316 were proposed as the replacement materials for the swirler. The other alternative of coating the existing swirlers with a form thermal barrier coating to observe for any improvement in their performance at elevated temperatures was also tested. Stellite, which is a Ni-Co based coating, was carried out on the MS samples and the same were exposed to same temperatures mentioned above. The performance of the available options was evaluated with respect to the grain structure of the material, the hardness value of the materials and deterioration at elevated temperatures. Investigation showed the proposed materials/coatings like SS 304, SS 316 and Stellite coating revealed that SS 316 is the material best suited for high temperature application.

  2. Hot Corrosion Studies of HVOF-Sprayed Coating on T-91 Boiler Tube Steel at Different Operating Temperatures

    Science.gov (United States)

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

    2013-11-01

    The aim of the present work is to investigate the usefulness of high velocity oxy fuel-sprayed 75% Cr3C2-25% (Ni-20Cr) coating to control hot corrosion of T-91 boiler tube steel at different operating temperatures viz 550, 700, and 850 °C. The deposited coatings on the substrates exhibit nearly uniform, adherent and dense microstructure with porosity less than 2%. Thermogravimetry technique is used to study the high temperature hot corrosion behavior of uncoated and coated samples. The corrosion products of the coating on the substrate are analyzed by using XRD, SEM, and FE-SEM/EDAX to reveal their microstructural and compositional features for the corrosion mechanisms. It is found that the coated specimens have shown minimum weight gain at all the operating temperatures when compared with uncoated T-91 samples. Hence, coating is effective in decreasing the corrosion rate in the given molten salt environment. Oxides and spinels of nickel-chromium may be the reason for successful resistance against hot corrosion.

  3. Rivesville multicell fluidized bed boiler. Annual technical progress report. July 1978-June 1979

    Energy Technology Data Exchange (ETDEWEB)

    1980-08-01

    Design, construction and test program of a 300,000 lb/hr steam generating capacity multicell fluidized bed boiler (MFB), as a pollution free method of burning high-sulfur or highly corrosive coals, is being carried out. The concept involves burning fuels such as coal, in a fluidized bed of limestone particles that react with the sulfur compounds formed during combustion to reduce air pollution. Nitrogen oxide emissions are also reduced at the lower combustion temperatures. The CaSO/sub 4/ produced in the furnace is discharged with the ash or regenerated to CaO for reuse in the fluidized bed. Information is presented on continued operation of the Rivesville MFB steam generating plant in a commercial mode and for determining performance and emission characteristics; studies and tests on flyash characterization and reinjection, fuel feed eductors and needles, air distributor, corrosion-erosion and sulfur capture; engineering studies to improve MFB performance and reliability.

  4. Technical and commercial considerations in selecting NOx reduction technology for utility boilers

    International Nuclear Information System (INIS)

    A technical and economic evaluation of technologies commercially available for the reduction of nitrous oxides is presented. The study was based on nitrogen oxide control alternatives for a 500 MW pulverized coal and oil fired utility boiler, with emphasis on post-combustion technologies. A combustion related technology examined was the XCL type DRB burner in combination with an overfire air system. Post-combustion technologies examined included selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR). It was concluded that if modest nitrogen oxides reduction is required for large utility boiler application, combustion related technologies such as low nitrogen oxide burners and overfire air systems should be given first consideration. If required reductions are beyond the capabilities of these systems, post combustion technologies must be considered. The lower capital cost of SNCR nitrogen oxide control systems is attractive, but technical risk, lack of large scale operating experience, and life cycle cost render it less attractive than SCR over 25 years of expected boiler operating life. 2 refs., 4 figs., 2 tabs

  5. Hot Corrosion Behaviour of Detonation Gun Sprayed Stellite-6 and Stellite-21 Coating on Boiler Steel SAE 431 at 900°C

    Directory of Open Access Journals (Sweden)

    N. K. Mishra

    2014-01-01

    Full Text Available Hot corrosion is the serious problem in gas turbines, superheaters, and economizers of coal-fired boilers. It occurs due to the usage of wide range of fuels such as coal, oil, and so on at the elevated temperatures. Protective coatings on boiler steels are used under such environments. In the present investigation, Stellite-6 and Stellite-21 coatings have been deposited on boiler steel SAE 431 by detonation gun method. The hot corrosion performance of Stellite-6 and Stellite-21 coated as well as uncoated SAE 431 steel has been evaluated in aggressive environment of Na2SO4-82%Fe2(SO43 under cyclic conditions at an elevated temperature of 900°C for total duration of 50 cycles. Thermogravimetric technique was used to approximate the kinetics of hot corrosion. Stellite-6 coating imparted better hot corrosion resistance than Stellite-21 coating in the given environment. Scanning electron microscopy was used to characterize the surface of hot corrosion products.

  6. High temperature corrosion in biomass- and waste fired boilers. A status report; Kunskapslaeget betraeffande hoegtemperaturkorrosion i aangpannor foer biobraensle och avfall

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, P.; Ifwer, K.; Staalenheim, A.; Montgomery, M.; Hoegberg, J.; Hjoernhede, A.

    2006-12-15

    Many biomass- or waste-fired plants have problems with high temperature corrosion on the furnace walls or at the superheaters, especially if the steam temperature is greater than 500 deg C. An increase in the combustion of waste fuels means that an increasing number of boilers have had problems. Therefore, there is great interest from plant owners to reduce the costs associated with high temperature corrosion. At the same time there exists a considerable driving force towards improving the electrical efficiency of a plant by the use of more advanced steam data. The purpose of the work presented here was to answer three main questions: What can be done to reduce high temperature corrosion with current fuel blends and steam temperatures? How can more waste fuels be burnt without an increased risk for corrosion? What needs to be done to reach higher steam temperatures in the future? The level of knowledge of high temperature corrosion in biomass- and waste-fired boilers has been described and summarised. The following measures are recommended to reduce corrosion in existing plant: Make sure that the fuel is well mixed and improve fuel feeding to obtain a more even spread of the fuel over the cross-section of the boiler. Use combustion technology methods to stabilize the oxygen content of the flue gases near the membrane walls and other heat transfer surfaces. Experiment with additives and/or supplementary fuels which contain sulphur in some form, for example peat. Reduce the flue gas temperature at the superheaters. Review soot-blowing procedures or protect heat transfer surfaces from soot blowers. Evaluate coated membrane wall panels in parts of the furnace that experience the worst corrosion. Test more highly alloyed steels suitable for superheaters and when replacing a superheater change to a more highly alloyed steel. For the future, the following should be considered: The role of sulphur needs to be investigated more and other additives should be investigated

  7. Increased Lifetime for Biomass and Waste to Energy Power Plant Boilers with HVOF Coatings: High Temperature Corrosion Testing Under Chlorine-Containing Molten Salt

    Science.gov (United States)

    Oksa, Maria; Tuurna, Satu; Varis, Tommi

    2013-06-01

    Heat exchanger surfaces of waste to energy and biomass power plant boilers experience often severe corrosion due to very aggressive components in the used fuels. High velocity oxy-fuel (HVOF) coatings offer excellent protection for boiler tubes against high temperature corrosion due to their high density and good adherence to the substrate material. Several thermal spray coatings with high chromium content were sprayed with HVOF technique. Their mechanical properties and high temperature corrosion resistance were tested and analyzed. The coating materials included NiCr, IN625, Ni-21Cr-10W-9Mo-4Cu, and iron-based partly amorphous alloy SHS9172 (Fe-25Cr-15W-12Nb-6Mo). High temperature corrosion testing was performed in NaCl-KCl-Na2SO4 salt with controlled H2O atmosphere at 575 and 625 °C. The corrosion test results of the coatings were compared to corrosion resistance of tube materials (X20, Alloy 263 and Sanicro 25).

  8. Extending the erosion-corrosion service life of the tube system of heat-recovery boilers used as part of combined-cycle plants

    Science.gov (United States)

    Tomarov, G. V.; Mikhailov, A. V.; Velichko, E. V.; Budanov, V. A.

    2010-01-01

    We present the results from an analysis of damageability and determination of dominating mechanisms through which thinning occurs to the metal of elements used in the tube system of heat recovery boilers used as part of combined-cycle plants during operation and during their outages. Results obtained from putting in use a technology for making the tubes of such boilers more resistant to erosion-corrosion wear with the aid of film-forming amines are also presented. Measures are proposed on extending the service life of the tube system of heat recovery boilers used as part of combined-cycle plants and operating under the conditions of single- and two-phase flows.

  9. Nickel- and iron-based HVOF thermal spray coatings for high temperature corrosion protection in biomass-fired power plant boilers

    OpenAIRE

    Oksa, Maria

    2015-01-01

    Biomass burning for production of electricity and heat has been increasing due to legislation in Europe. Growing awareness of environmental problems has led to strict restrictions on greenhouse emissions in the energy sector, and increased demand for higher use of renewable energy sources and carbon-neutral fuels, such as biomass. There are over 1000 biomass boilers in Europe, and the number is increasing. These plants often face serious problems due to high temperature corrosion. Fouling and...

  10. Study on the corrosion inhibition characteristic of HEDP in industrial boiler water%工业锅炉炉水中HEDP缓蚀特性研究

    Institute of Scientific and Technical Information of China (English)

    朱志平; 李茂东; 金鹏; 袁汉涛; 邹志超; 黄先军

    2014-01-01

    Using electrochemical impedance spectroscopy and Tafel polarization method in simulated boiler water medium of the low pressure industrial boiler,the HEDP corrosion inhibition capacity for 20 # carbon steel has been studied. The effects of Ca2+,Cl-and SO42-in boiler water on the corrosion inhibition capacity of HEDP are discussed. The results show that when 25 mg/L of HEDP is added to the stimulated boiler water medium,the best corrosion in-hibition result can be obtained. he inhibition effect of HEDP on carbon steel is mainly in anode betatopic reaction. HEDP is a kind of corrosion inhibitor mainly used for inhibiting anode. The presence of Ca2+in boiler water can af-fect the polarization process of carbon steel electrode by HEDP. The erosive anions,such as Cl-and SO42-etc. can in-tensify the corrosion and have negative effect on HEDP corrosion inhibiting capacity.%使用电化学阻抗法及Tafel极化法在模拟低压工业锅炉炉水介质中研究了HEDP对20#碳钢的缓蚀性能,并探讨了炉水中Ca2+、Cl-以及SO42-对HEDP缓蚀性能的影响。实验结果表明:在模拟炉水介质中,当HEDP投加量为25 mg/L时,其对碳钢具有最佳的缓蚀效果;HEDP对碳钢腐蚀的抑制主要作用于阳极失电子反应,HEDP是一种以抑制阳极为主的缓蚀剂;炉水中Ca2+的存在会影响HEDP对碳钢电极的极化过程;Cl-、SO42-等侵蚀性阴离子会促进腐蚀的加剧,影响HEDP的缓蚀性能。

  11. The erosion-corrosion of boiler inlet ferrule assemblies: Part 4

    International Nuclear Information System (INIS)

    Results are given for four experiments carried out on the CERL Isothermal Rig aimed at defining the temperature and flow dependency of erosion-corrosion at pH 9.30 and 9.50. At pH 9.50 it was found that the flow dependency for the maximum rate in the post-orifice region was relatively low, Vsup(1.08) to Vsup(1.34), and showed only a small variation with temperature, the dependency tending to increase with increasing temperature. This behaviour differs from that seen at pH 9.04 where a higher flow dependency and a greater variation with temperature was seen. An assessment of the available data indicates that the flow dependency falls significantly as pH rises from 9.0 to 9.3, but that thereafter there is little further change up to pH 9.65. The temperature dependency at pH 9.50 gave a peak in the erosion-corrosion rate at about 1350C, the position of which moved to higher temperatures with increasing rates. Compared with the data at pH 9.04, the temperature maxima occurred at higher temperatures at equivalent erosion-corrosion rates. A comparison of the data at pH 9.04 and 9.50 shows that there is no unique pH dependency for erosion-corrosion under the conditions tested. At 1150C an almost constant pH dependency was found, but at higher temperatures there was a marked variation in pH dependency with flow. For 100% MCR conditions at 1490C, the present data are consistent with those obtained in early Isothermal Rig experiments. (author)

  12. Relations between combustion, deposition, flue gas temperatures and corrosion in straw-fired boilers

    DEFF Research Database (Denmark)

    Montgomery, Melanie

    2004-01-01

    using an aluminium silicate additive, however the relative chlorine content of the deposits was unchanged. At Ensted woodchip plant, a dosage level of additives was reached which reduced the chlorine flux. For straw firing where the chlorine level in the fuel is higher and the fuel load is greater......ABSTRACT: Additives trials in three different plants, Sønderborg waste incineration plant and Ensted woodchip and straw firing boiler, are described. Both aluminium silicate containing additives and ammonium sulphate was tested. At Sønderborg, there was a drastic decrease in Cl deposition when......, the chlorine flux on deposition probes was not affected by additive dosage. An indication that some chlorine had been removed could be measured by the increased HCl output during additive dosage. The importance of temperature and where the additive is dosed is discussed....

  13. Stress Corrosion Cracking of SA-543 High-Strength Steel in All-Volatile Treatment Boiler Feed Water

    Science.gov (United States)

    Rihan, R.; Basha, M.; Al-Meshari, A.; Bayramov, A.; van Zyl, G.; Dafalla, H.; Mohamed, A. I.

    2015-10-01

    Susceptibility of SA-543 steel, its welds (with and without stress relief treatment), and the heat-affected zone (HAZ) to stress corrosion cracking (SCC) was investigated in de-aerated and aerated boiler feed water subjected to the all-volatile treatment (AVT-BFW), and distilled water at 275 °C using the slow strain rate testing (SSRT) technique. The SSRT specimens were tested at three extension rates (3.50 × 10-6, 9.00 × 10-6, and 7.50 × 10-5 mm/s) using a novel SCC testing rig capable of testing at high temperatures and pressures. There are no significant differences in the time-to-failure among the four tested specimens. The elongation of the specimens at the time of failure is in the range of 10-23%. The reduction of the cross-sectional area of the failed specimens is large (45-77%) and the absence of any signs of intergranular propagation in fractured specimens, determined by scanning electron microscopy, indicates that the failure is due to mechanical load and not due to SCC. Dissolved oxygen does not affect the susceptibility of the specimens to SCC, which could be due to the inhibition effect of the test solution. SA-543 steel as the base metal, its welds (with and without stress relief treatment), and the HAZ are suitable for use in hot AVT-BFW and distilled water.

  14. A Study of the Effect of Kaolin as a Fuel Oil Additive on the Corrosion Inhibition of Fireside Superheater Boiler Tubes

    Directory of Open Access Journals (Sweden)

    Alaa' Mshjel Ali

    2010-01-01

    Full Text Available The objective of the present study is to determine the effect of Kaolin as a fuel oil additive to minimize the fireside corrosion of superheater boiler tubes of ASTM designation (A213-T22 by increasing the melting point of the formed slag on the outside tubes surface, through the formation of new compounds with protective properties to the metal surface. The study included measuring corrosion rates at different temperatures with and without additive use with various periods of time, through crucible test method and weight loss technique.A mathematical model represents the relation between corrosion rate and the studied variables, is obtained using statistical regression analysis. Using this model, the best additive to ash weight ratio was specified. Then scanning electron microscopic images taken to the two treated and untreated samples with additive to study the difference in nature of slag formed on the metal surface to the two cases.

  15. Comparative High-Temperature Corrosion Behavior of Ni-20Cr Coatings on T22 Boiler Steel Produced by HVOF, D-Gun, and Cold Spraying

    Science.gov (United States)

    Kaushal, Gagandeep; Bala, Niraj; Kaur, Narinder; Singh, Harpreet; Prakash, Satya

    2014-01-01

    To protect materials from surface degradations such as wear, corrosion, and thermal flux, a wide variety of materials can be deposited on the materials by several spraying processes. This paper examines and compares the microstructure and high-temperature corrosion of Ni-20Cr coatings deposited on T22 boiler steel by high velocity oxy-fuel (HVOF), detonation gun spray, and cold spraying techniques. The coatings' microstructural features were characterized by means of XRD and FE-SEM/EDS analyses. Based upon the results of mass gain, XRD, and FE-SEM/EDS analyses it may be concluded that the Ni-20Cr coating sprayed by all the three techniques was effective in reducing the corrosion rate of the steel. Among the three coatings, D-gun spray coating proved to be better than HVOF-spray and cold-spray coatings.

  16. Superheater corrosion in biomass boiler - theories and tests in Vaestermalmsverket, Falun; Oeverhettarkorrosion i bioeldad panna - teorier och prov i Vaestermalmsverket, Falun

    Energy Technology Data Exchange (ETDEWEB)

    Roennquist, Eva-Marie

    2000-10-01

    It has lately been evident that a number of biomass-fired plants are experiencing major problems with corrosion of their superheaters. The major aim with this project is to contribute with increased knowledge in this area. The efforts to build up experience around different materials applicable for superheaters with high steam data is of great importance for future plants in Sweden. The main objective for 'Vaermeforsk' has been to transfer the experiences from this investigation to other boilers or plants with different types of fuel. This investigation has therefore been focused on the verification of SYCON's assumptions regarding the roles of chloride and alkali and the possibility of influencing/minimising superheater corrosion by optimisation of the fuel mix. Another important part was to verify that the boiler design, as such, does not create an unfavourable environment for the superheaters by producing reducing zones due to plume formation. Based on the above, the investigation has been divided into three loosely connected parts. (1) The role and reaction by chlorides in the deposits on a superheater, (2) Reducing environment - plume formation of non-combusted fuel, and (3) Choice of materials in the superheater. Serious corrosion has been detected in the superheater tubes of 'Vaestermalmsverket' in Falun. The material temperature was below 530 deg C. No serious inhomogeneous combustion problems or areas with reducing environments have been detected. The corrosion was therefore judged to be caused by alkali chlorides which condense on the superheater tubes. Tests with minor amounts of sulphur added to the biomass fuel have been shown to suppress the generation of alkali chlorides and their condensation on the superheater surfaces. A good correlation between calculated and measured values have been achieved. Very low corrosion rates have been measured on the test probes, constructed with different superheater material and placed in the

  17. Corrosion

    Science.gov (United States)

    Slabaugh, W. H.

    1974-01-01

    Presents some materials for use in demonstration and experimentation of corrosion processes, including corrosion stimulation and inhibition. Indicates that basic concepts of electrochemistry, crystal structure, and kinetics can be extended to practical chemistry through corrosion explanation. (CC)

  18. Complex thermo - technical tests of the boiler OB 380 at TPP 'Oslomej' (Macedonia)

    International Nuclear Information System (INIS)

    Further improvement of good production results of Thermal Power Plant 'Oslomej' - Macedonia, respectively elimination of the existing difficulties and limitation as well as the preparation of the reconstruction and life extension program, have been based on the execution of a complex Program of investigations, of the boiler operating conditions. Program has been composed by: a closer characterization of lignite and its behavior in the pulverized coal preparation system, an investigation of the furnace heat exchange conditions, an investigation of metal temperature regimes of all high temperature loaded heat exchangers, an investigation of boiler efficiency and measurements of noxious gases contents in the exit flue gases. Results of the investigations have shown a full justification of the complex approach and simultaneous execution of investigation of different boiler processes and tracts. Using such approach an extensively broad picture about operating processes, under defined conditions, have been obtained. Namely, results of investigations of different boiler processes have been interpreted on a such way to show, in a real light their essential interconnections. The conclusion of all investigations have pointed to the necessity of the execution of the numerous measure. Elimination of the imperfections of the main and auxiliary equipment, under the execution of maintenance works, reconstruction and modernizing, as well as a further adjustments of the boiler operation processes can result in the achievement of targeted goals. A further coordinated action of the lignite mine and power plant is one of the main preconditions. Results are presented in details in other symposium papers. (Author)

  19. 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.

  20. Differences in the German and French systems of technical and legal regulations, as shown by the example of the boiler codes. Pt. 1

    International Nuclear Information System (INIS)

    As the coordination of technical rules and standards applicable within the individual EC member states proceeds only slowly, manufactures, operators and inspection authorities still have to observe, for the time being, the various national codes and standards when importing or exporting technical installations within the EC. Using the national boiler as an example codes, currently existing technical and legal regulations and testing and inspection procedures applied in France are explained and compared with those to be applied in the FRG. (orig.)

  1. Corrosion Behavior of TP316L of Superheater in Biomass Boiler with Simulated Atmosphere and Deposit%TP316L在模拟生物质锅炉过热器气相和积灰条件下的腐蚀特性

    Institute of Scientific and Technical Information of China (English)

    印佳敏; 吴占松

    2009-01-01

    Corrosion behavior of TP316L was investigated with simulated atmosphere and ash deposition for the superheater in biomass boiler. Corrosion dynamic curves were plotted by mass gain. The results showed that the corrosion was dependent on temperature and was greatly accelerated by ash deposition. The mass gain was distinctly reduced in the presence of SO_2 with and without ash deposition on the specimens. Corrosion rates with ash deposit at different temperatures were calculated. Two feasible methods were provided to avoid serious high-temperature corrosion in the biomass boiler.

  2. Water Chemistry and Clad Corrosion/Deposition Including Fuel Failures. Proceedings of a Technical Meeting

    International Nuclear Information System (INIS)

    Corrosion is a principal life limiting degradation mechanism in nuclear steam supply systems, particularly taking into account the trends in increasing fuel burnup, thermal ratings and cycle length. Further, many plants have been operating with varying water chemistry regimes for many years, and issues of crud (deposition of corrosion products on other surfaces in the primary coolant circuit) are of significant concern for operators. At the meeting of the Technical Working Group on Fuel Performance and Technology (TWGFPT) in 2007, it was recommended that a technical meeting be held on the subject of water chemistry and clad corrosion and deposition, including the potential consequences for fuel failures. This proposal was supported by both the Technical Working Group on Advanced Technologies for Light Water Reactors (TWG-LWR) and the Technical Working Group on Advanced Technologies for Heavy Water Reactors (TWG-HWR), with a recommendation to hold the meeting at the National Nuclear Energy Generating Company ENERGOATOM, Ukraine. This technical meeting was part of the IAEA activities on water chemistry, which have included a series of coordinated research projects, the most recent of which, Optimisation of Water Chemistry to Ensure Reliable Water Reactor Fuel Performance at High Burnup and in Ageing Plant (FUWAC) (IAEATECDOC-1666), concluded in 2010. Previous technical meetings were held in Cadarache, France (1985), Portland, Oregon, USA (1989), Rez, Czech Republic (1993), and Hluboka nad Vltavou, Czech Republic (1998). This meeting focused on issues associated with the corrosion of fuel cladding and the deposition of corrosion products from the primary circuit onto the fuel assembly, which can cause overheating and cladding failure or lead to unplanned power shifts due to boron deposition in the clad deposits. Crud deposition on other surfaces increases radiation fields and operator dose and the meeting considered ways to minimize the generation of crud to avoid

  3. 处理后的油田污水对热采锅炉20G腐蚀性的研究%CORROSIVITY OF TREATED WASTEWATER ON STEEL 20GOF BOILER FOR THERMAL PRODUCTION WELL IN OIL FIELD

    Institute of Scientific and Technical Information of China (English)

    温建萍; 李文戈; 李海; 张乃峰; 温涛

    2001-01-01

    The corrosion behavior of steel 20G in wastewater treatment system has been investigated by means of the weight loss test combining with optical microscope、SEM and XPS etc..The results show that the corrosion of boiler steel 20G in wastewater,which has been treated,is serious with obvious feature of pitting corrosion.Therefore,the treated wastewater should be excluded from futher use for boiler for thermal production well in oil field.%通过现场挂片试验,应用光学显微镜、扫描电镜、X射线能谱分析方法研究了20G材料在油田污水中的腐蚀性.结果表明,处理后的污水对高温高压锅炉材料的腐蚀严重,不能用于热采锅炉.

  4. Studies on Hot Corrosion of the Microstructurally Different Regions of 2.25Cr-1Mo (T22) Boiler Tube Steel Weldment

    Science.gov (United States)

    Kumar, Ravindra; Tewari, V. K.; Prakash, Satya

    2009-10-01

    This study examines the effect of microstructurally different regions on the hot corrosion of tungsten inert gas weldment in 2.25Cr-1Mo (T22) boiler tube steel. Various regions of weldment were oxidized in molten salt Na2SO4-60% V2O5 environment at 900 °C. The base metal was found to oxidize at much higher rates than the weld metal and the heat-affected zone. Oxide scales formed in the three regions were compared by scanning electron microscopy with energy dispersive of X-ray analysis, X-ray diffraction pattern, and electron probe microanalysis. The research investigates the formation of inner scales with free Cr over the HAZ.

  5. Boiler Chemical Cleaning Corrosion Control Study Of Fe3+%锅炉化学清洗中Fe3+的腐蚀控制研究

    Institute of Scientific and Technical Information of China (English)

    李先国

    2016-01-01

    为了研究SA-213此类材料受到不同Fe3+质量浓度的影响而造成的腐蚀程度,并进一步研究Fe3+受到清洗工作影响的实际情况,就需要在静态的环境下制定试验溶液—甲酸+羟基乙酸(复合有机酸)锅炉清洗液。但需要注意的是,此溶液的配置必须是在使用腐蚀失重法和电化学法的基础上。笔者根据多方面的研究调查得出,金属材质的锅炉或受到Fe3+的严重腐蚀,并且腐蚀的面积会随着金属含量的增加而不断扩散;为了控制不断增长的Fe3+速率,按照相关要求将一定比例的还原剂放入了试验中,并采取了系统隔绝空气的措施,使得剩余酸的浓度得以保持在标准范围,对Fe2+的转换起到了控制作用。%The extent of corrosion in order to investigate sa-213 such materials affected differently Fe3+ concentration is caused, and further study of Fe3+ by cleaning the impact was the actual situation,we need to develop a test solution in a static environment-formic acid and glycolic acid(organic compound)boiler cleaning fluid,but it should be noted that the configuration of this solution must be based on the use of corrosion weight loss and electrochemical measurements on.According to the author of many research surveys,boiler or metal Fe3+ by severe corrosion,corrosion and area with increasing metal content and has continued to spread;in order to control the increasing rate of Fe3+,we will be in accordance with the relevant requirements of certain the concentration ratio of the reducing agent into the test,and to take measures to isolate the air system,the remaining acid is maintained in the standard range, the effective conversion of Fe2+ has played a controlling role.

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

    Directory of Open Access Journals (Sweden)

    P. Ratnikov

    2013-01-01

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

  7. 浅谈降低300MW锅炉NOX排放的措施%Technical measures of reducing the NOx emission in 300MW boiler

    Institute of Scientific and Technical Information of China (English)

    汪宁

    2012-01-01

    分析了我国300MW锅炉NOX排放的现状。介绍黔北发电厂300MW东方锅炉在技术改造、操作调整等方面降低NOX排放的措施,减少300MW锅炉的NOX排放。%The current situation of NOx emission of 300MW utility boilers in China is being analyzed.Technical measures of reducing the NOx emission quantity in Qianbei Power Plant are introduced,such as transformation program,operation adjustment,which reduced the NOx emission in 300MW boiler.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-06-30

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xingbo

    2015-06-30

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

  10. 油田热电厂注汽锅炉炉管腐蚀因素分析与控制措施%Corrosion Factors Analysis and Control Measures of Boiler Tubes in Steam In?jection Boiler in the Oilfield

    Institute of Scientific and Technical Information of China (English)

    周登印

    2016-01-01

    The steam injection boiler furnace tube of Daqing oilfield thermal power plant is in high temperature, high pressure and other harsh environmental conditions. The corrosion types are mainly alkali corrosion,dissolved oxygen corrosion,cavitation erosion,steam wa-ter corrosion and stop furnace corrosion. The corrosion factors produced by the medium mainly include temperature, flow rate and water treatment quality. The dissolved oxygen in the oxygen, and the boiler water in the steam injection boiler furnace, that have accelerated the corrosion rate of the furnace tubes. On the basis of corrosion factors targeted research, from the control of boiler feed water quality, reduce boiler oxygen exposure probability and improve the furnace pipe anti-corrosion properties of the essence, four aspects:the use of science and technology,and puts forward the corresponding control measures,aiming to de-lay and reduce the corrosion of all aspects, to prevent corrosion of the probability of more than 99.9%. By controlling the water quality of boiler and reducing the chance of contact with oxygen,the corrosion of boiler tubes is reduced.%大庆油田热电厂注汽锅炉炉管处于高温、高压的恶劣环境工况,腐蚀严重,其腐蚀类型主要为碱腐蚀、溶解氧腐蚀、气蚀、汽水腐蚀和停炉腐蚀.由介质产生的腐蚀因素主要有温度、流速及水处理质量;注汽锅炉炉管中存在的氧气以及锅炉水中溶解的氧加速了炉管腐蚀速率.为延缓腐蚀并减小腐蚀程度,提出以下对应的控制措施:严把水质源头管控,杜绝出现不达标水质进入锅炉;完善运行参数,防止超温、超压环境出现;将多种除氧方法结合使用,以达到最佳除氧效果.停炉后采用TH901法在炉管表面形成保护膜以隔离氧气,该保护法加药量少,成本低,阻止腐蚀的概率达到99.9%以上.通过控制锅炉给水水质,减少锅炉接触氧几率等措施,减缓了注汽锅炉炉管的腐蚀.

  11. Technical and economic feasibility of utilizing apple pomace as a boiler feedstock

    Energy Technology Data Exchange (ETDEWEB)

    Sargent, S.A.

    1983-01-01

    Apple pomace or presscake, was evaluated for suitability as a boiler feedstock for Michigan firms processing apple juice. Based upon the physical and chemical characteristics of pomace, handling/direct combustion systems were selected to conform with operating parameters typical of the industry. Fresh pomace flow rates of 29,030 and 88,998 kg/day (64,000 and 194,000 lb/day) were considered as representative of small and large processors, respectively, and the material was assumed to be dried to 15% moisture content (wet basis) prior to storage and combustion. Boilers utilizing pile-burning, fluidized-bed-combustion, and suspension-firing technologies were sized for each flow rate, resulting in energy production of 2930 and 8790 kW (10 and 30 million Btu/h), respectively. A life-cycle cost analysis was performed giving Average Annual Costs for the three handling/combustion system combinations (based on the Uniform Capital Recovery factor). An investment loan at 16% interest with a 5-year payback period was assumed. The break-even period for annual costs was calculated by anticipated savings incurred through reduction of fossil-fuel costs during a 5-month processing season. Large processors, producing more than 88,998 kg pomace/day, could economically convert to a suspension-fired system substituting for fuel oil, with break-even occurring after 4 months of operation of pomace per year. Small processors, producing less than 29,030 kg/day, could not currently convert to pomace combustion systems given these economic circumstances. A doubling of electrical-utility costs and changes in interest rates from 10 to 20% per year had only slight effects on the recovery of Average Annual Costs. Increases in fossil-fuel prices and the necessity to pay for pomace disposal reduced the cost-recovery period for all systems, making some systems feasible for small processors. 39 references, 13 figures, 10 tables.

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

    Energy Technology Data Exchange (ETDEWEB)

    Uth, Joern

    2010-08-15

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

  13. 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.

  14. 锅炉水汽系统一、二次网腐蚀问题的分析与解决%Analysis and solution examples for the first and second network corrosion of boiler water gas system

    Institute of Scientific and Technical Information of China (English)

    肖强; 沈晓东

    2012-01-01

    锅炉的“红水问题”是由于炉水对锅炉本体及系统设备的腐蚀造成的,其不仅会使凝结水无法回用,造成大量的补充水和能源的损失,还会对锅炉本身、后续相关系统的设备造成损坏,甚至对相关操作人员的安全都造成威胁.从一次网和二次网的腐蚀原因入手,通过分析分别找到各自系统存在的问题,提出解决方案,现场应用时收到了良好的效果.%The "red water" problem of boilers is caused by the corrosion effect of the boiler water on the boiler body and the equipment of the system. Because of the corrosion, the condensation water cannot be reused, which results in the great loss to make-up water and energy. The corrosion also damages the boiler as well as the follow-up system equipment, or even threatens the safety of the related operating personnel. Starting from the mechanism of the first and second network corrosion, and by way of analysis, the problems in each system have been found out, and solutions which were put forward and applied to worksites have received good effects.

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

    Energy Technology Data Exchange (ETDEWEB)

    Mike Bockelie; Marc Cremer; Kevin Davis; Bob Hurt; Eric Eddings

    2001-01-31

    This is the second 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 focus of our efforts during the last three months have been on: (1) Completion of a long term field test for Rich Reagent Injection (RRI) at the Conectiv BL England Station Unit No.1, a 130 MW Cyclone fired boiler; (2) Extending our Computational Fluid Dynamics (CFD) based NOx model to accommodate the chemistry for RRI in PC fired boilers; (3) Design improvements and calibration tests of the corrosion probe; and (4) Investigations on ammonia adsorption mechanisms and removal processes for Fly Ash.

  16. Corrosion/95 conference papers

    International Nuclear Information System (INIS)

    The papers in this conference represent the latest technological advances in corrosion control and prevention. The following subject areas are covered: cathodic protection in natural waters; materials for fossil fuel combustion and conversion systems; modern problems in atmospheric corrosion; innovative ideas for controlling the decaying infrastructure; deposits and their effects on corrosion in industry; volatile high temperature and non aqueous corrosion inhibitors; corrosion of light-weight and precoated metals for automotive application; refining industry corrosion; corrosion in pulp and paper industry; arctic/cold weather corrosion; materials selection for waste incinerators and associated equipment; corrosion measurement technology; environmental cracking of materials; advancing technology in the coating industry; corrosion in gas treating; green inhibition; recent advances in corrosion control of rail equipment; velocity effects and erosion corrosion in oil and gas production; marine corrosion; corrosion of materials in nuclear systems; underground corrosion control; corrosion in potable and industrial water systems in buildings and its impact on environmental compliance; deposit related boiler tube failures; boiler systems monitoring and control; recent developments and experiences in reactive metals; microbiologically influenced corrosion; corrosion and corrosion control for steel reinforced concrete; international symposium on the use of 12 and 13 Cr stainless steels in oil and gas production environments; subsea corrosion /erosion monitoring in production facilities; fiberglass reinforced pipe and tubulars in oilfield service; corrosion control technology in power transmission and distribution; mechanisms and methods of scale and deposit control; closing the loop -- results oriented cooling system monitoring and control; and minimization of aqueous discharge

  17. Water chemistry and corrosion control of cladding and primary circuit components. Proceedings of a technical committee meeting

    International Nuclear Information System (INIS)

    Corrosion is the principal life limiting degradation mechanism in nuclear steam supply systems, especially taking into account the trends to increase fuel burnup, thermal rate and cycle length. Primary circuit components of water cooled power reactors have an impact on Zr-based alloys behaviour due to crud (primary circuit corrosion products) formation, transport and deposition on heat transfer surfaces. Crud deposits influence water chemistry, radiation and thermal hydraulic conditions near cladding surface, and by this way-Zr-based alloy corrosion. During the last decade, significant improvements were achieved in the reduction of the corrosion and dose rates by changing the cladding material for one more resistant to corrosion or by the improvement of water chemistry conditions. However, taking into account the above mentioned tendency for heavier fuel duties, corrosion and water chemistry, control will remain a serious task to work with for nuclear power plant operators and scientists, as well as development of generally accepted corrosion model of Zr-based alloys in a water environment in a new millennium. Upon the recommendation of the International Working Group on Water Reactor Fuel Performance and Technology, water chemistry and corrosion of cladding and primary circuit components are in the focus of the IAEA activities in the area of fuel technology and performance. At present the IAEA performs two co-ordinated research projects (CRPs): on On-line High Temperature Monitoring of Water Chemistry and Corrosion (WACOL) and on Activity Transport in Primary Circuits. Two CRPs deal with hydrogen and hydride degradation of the Zr-based alloys. A state-of-the-art review entitled: 'Waterside Corrosion of Zirconium Alloys in Nuclear Power Plants' was published in 1998. Technical Committee meetings on the subject were held in 1985 (Cadarache, France), 1989 (Portland, USA), 1993 (Rez, Czech Republic). During the last few years extensive exchange of experience in

  18. Evaluation of MELTGUARD{sup TM} - a measuring system for control of fireside corrosion in boilers; Utvaerdering av MELTGUARD{sup TM} - ett maetsystem foer kontroll av roekgassidig korrosion i pannor

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, Pamela [Vattenfall Utveckling AB, Stockholm (Sweden)

    2001-10-01

    Studsvik AB has developed and now owns the patent for a product called MELTGUARD. According to information from Studsvik, Meltguard is a measuring probe that shows in real-time how much corrosion is occurring and that can reduce costs and increase the lifetime of power boilers burning biomass. The product consists of a tubular air-cooled probe which is exposed in the flue gas through an existing inspection port. The electrodes in the probe react with the flue gas and ash deposit and corrosion is registered as the short-circuited corrosion current (using the zero resistance method) between rings made of the investigated material. The aim of the project was to independently evaluate Meltguard, compare it with a conventional corrosion probe and to publish the results for the Swedish thermal power industry. Two steels have been compared on the probes (a Meltguard-probe can accommodate a maximum of two test pieces), with about the same temperature. Measurements have been carried out with the steels SS2218 (T22) and Esshete 1250 on a Meltguard probe in the biomass fired boiler at Naessjoe combined heat and power plant during the period November 2000 to March 2001. For a 48 hour period sulphur was added to the fuel supply to change the fuel chemistry and influence the corrosion rate. The corrosion current for SS2218 was unstable, fluctuating considerably throughout the measuring period, and was greatly affected by soot-blowing. Usually, soot-blowing resulted in a marked decrease in the corrosion current. No simple or clear relationship between the boiler load and the average corrosion current could be determined. The corrosion current for Esshete 1250 was mostly stable, about 20{mu}A. The current for SS2218 was a little higher than that for E1250, but the relationship between current and corrosion rate was unclear. It was obviously not a linear function as the corrosion measured in 2218, when the testing was completed, was approximately four times greater than that in E

  19. Arc-Sprayed Iron-Based Coatings for Erosion-Corrosion Protection of Boiler Tubes at Elevated Temperatures

    Science.gov (United States)

    Pokhmurskii, Vasyl; Student, Mykhailo; Gvozdeckii, Volodymyr; Stypnutskyy, Taras; Student, Oleksandra; Wielage, Bernhard; Pokhmurska, Hanna

    2013-06-01

    Wire arc spraying is an economically attractive thermal spray process that is especially interesting for the protection of large-scale parts or constructions. This study presents the results of the development and investigation of a number of cored wires based on the Fe-Cr-Al system with minor addition of alloying elements (B, Mn, Ni, Si, Ti, Mg, etc.). The microstructure of the coatings, their electrochemical behavior, and isothermal oxidation performance over a temperature range of 20-700 °C were investigated. Erosion resistance at elevated temperatures was determined with a laboratory test unit under test conditions that have simulated the work conditions in fossil-fuel-fired boilers. It was established that the oxidation resistance and the gas-abrasive wear resistance of arc-sprayed coatings depend mostly on the coating microstructure and homogeneity of element distribution rather than on the general alloying level and microhardness of the coating. A new parameter for coating characterization, namely, the coefficient of chemical microheterogeneity, K CMH, is introduced to quantify this influence. Formation of the coating microstructure at elevated temperatures and its influence on the protection ability of the coating are discussed.

  20. Design, construction, operation, and evaluation of a prototype culm-combustion boiler/heater unit. Quarterly technical progress report, October 1-December 31, 1980

    Energy Technology Data Exchange (ETDEWEB)

    1981-02-01

    This report provides a summary of the work performed on the Prototype Culm Combustion Boiler/Heater Unit, Phase I - Engineering Design and Analysis and Phase II - Prototype Plant Construction during the period October 1, 1980 through December 31, 1980. The objectives of the program as well as the technical progress and problem areas encountered during the reporting period are presented. The final detail design effort was completed and the final design report submitted. Progress on procurement activity authorized by full Phase II release on March 20, 1980, is discussed. Following approval by DOE, a purchase order was placed with the Norflor Construction Corporation for the prototype plant construction which began in November. Construction of the access roadway installation of the electric power, sewer and water lines was completed during this reporting period. Boiler construction continued.

  1. 锅炉设备碱性腐蚀原因分析及水处理工艺改进%Analysis on the causes of boiler equipment alkaline corrosion and improvements on water treatment process

    Institute of Scientific and Technical Information of China (English)

    肖强; 霍文敏; 陆明

    2013-01-01

    锅炉的碱性腐蚀经常被人们所忽视,但其造成的后果往往是非常严重的,轻则造成爆管导致停产,重则会威胁到操作人员的人身安全.传统的锅炉水处理方法虽然价格低廉,但其存在先天的不足,在一定条件下无法阻止碱性腐蚀的发生.而近些年逐渐产生的锅炉水处理工艺及与其配套的有机锅炉水处理药剂则全方面改进了传统锅炉水处理方法的不足,并在现场应用中收到了良好的效果.%The problem of boiler equipment alkaline corrosion has always been neglected,resulting in serious consequence.It causes the burst of pipes leading to suspending operations,or threaten the safety of the operation staff.Although the price for traditional water treatment process is low,it has congenitally deficiency.It can not prevent the happening of alkaline corrosion under certain conditions.However,nowadays,some new boiler water treatment processes and organic boiler water treatment agents that go with the process can improve the deficiency of traditional boiler water treatment methods.It has been used in field application and received good effects.

  2. 用于燃气锅炉低碳钢耐冲蚀-腐蚀磨损的双层热喷涂层%Thermal Sprayed Dual-layer Coatings for Steel Protection against Corrosion-Erosion at Power Boilers

    Institute of Scientific and Technical Information of China (English)

    王卜谦; 税正荣; 王海斗

    2001-01-01

    为防护发电厂锅炉的热交换器管道的腐蚀冲蚀磨损,研究开发了一种热喷涂双层涂层(高速火焰喷涂Cr3C2/TiC–25NiCr涂层+燃烧电弧喷涂Ni21Cr9Mo35Nb涂层).在锅炉管道上实际应用两年后,对这种双涂层进行冲蚀试验和金相分析,并对其性能进行讨论.结果发现,燃烧电弧喷涂Ni21Cr9Mo3.5Nb涂层在高硫及氯环境中是一种良好的防护涂层.%The heat exchanger tubes of power plant boilers suffer from corrosion-erosion by ash particles and corrosive gases attack at elevated temperatures. The tube wastage rate depends on the boiler design and operation, the characteristics of ash particles, environment conditions, and tube materials. Thermal sprayed dual-layer coatings (HVOF Cr3C2/TiC-25NiCr coating and combustion arc-sprayed Ni21Cr9Mo3.5Nb coating) were developed for the tube corrosion-erosion protection. The erosion test comparison and metallographic examination of the coated tube after two years service in boiler were presented and its performance was discussed. The combustion arc-sprayed Ni21Cr9Mo3.5Nb coating was found a good solution for relatively high sulfur and chlorine environment.

  3. FY 2000 Tanks Focus Area Corrosion Monitoring Technical Committee Meeting Summary Report

    International Nuclear Information System (INIS)

    The primary purpose of the annual meeting between the corrosion monitoring personnel at the various DOE sites is to facilitate communications and promote technology transfer between the two sites. The close communications and good spirit of teamwork being exhibited between the parties representing the Hanford and Savannah River Sites has helped the Savannah River Site effort avoid many of the problems encountered during the initial development effort at Hanford. Similar benefits can be expected over the next few years as the ORNL program is developed. Expected products of this meeting as defined in Milestone A.4-1 of TTP RL0-9-WT-41 are reports on the status of technical work at the sites, discussions of emerging technical issues, and results of laboratory experiments and field trials. The formal meeting, informal discussions throughout the week, and the presentation materials shown in the attachment to this document fulfill the expectations of this meeting. At the conclusion of the meeting it was agreed that close communications should continue between the concerned parties at ORNL, SRTC and Hanford. Tentative plans were made to hold a similar meeting in approximately one year

  4. Experimental Study on Under-deposit Corrosion of Water Wall Tube in a 420t Utility Boiler%一台420t电站锅炉水冷壁管垢下腐蚀试验研究

    Institute of Scientific and Technical Information of China (English)

    李勇; 赵彦杰; 欧俊

    2015-01-01

    在对某电厂一台420t电站锅炉检验过程中,发现该锅炉水冷壁管存在结垢现象,水冷壁管垢下腐蚀会对锅炉的安全、经济运行造成影响。通过均匀腐蚀失效试验、氢脆腐蚀失效试验确定其腐蚀原理,并对其腐蚀速率进行了研究。%There were two under-deposit corrosion forming causes, uniform corrosion and hydrogen corrosion. In the inspection of a 420t/h utility boiler, scaling was found in its water wall tube leading to the temperature difference between different sides of water wall tube. The safety and economy will be affected. Through theory and experiment, corrosion mechanism and prevention measures were presented in this paper.

  5. SRC burn test in 700-hp oil-designed boiler. Volume 1. Integrated report. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    1983-09-01

    This burn test program was conducted during the period of August 1982 to February 1983 to demonstrate that Solvent Refined Coal (SRC) products can displace petroleum as a boiler fuel in oil- and gas-designed boilers. The test program was performed at the U.S. Department of Energy's Pittsburgh Energy Technology Center (PETC). Three forms of SRC (pulverized SRC, a solution of SRC dissolved in process-derived distillates, and a slurry of SRC and water) and No. 6 Fuel Oil were evaluated in the 700-hp (30 x 10/sup 6/ Btu/hour) watertube, oil-designed boiler facility at PETC. The test program was managed by the International Coal Refining Company (ICRC) and sponsored by the Department of Energy. Other organizations were involved as necessary to provide the expertise required to execute the test program. This final report represents an integrated overview of the test program conducted at PETC. More detailed information with preliminary data can be obtained from separate reports prepared by PETC, Southern Research Institute, Wheelabrator-Frye, Babcock and Wilcox, and Combustion Engineering. These are presented as Annex Volumes A-F. 25 references, 41 figures, 15 tables.

  6. Biomass boilers

    OpenAIRE

    Nahodil, Jiří

    2011-01-01

    Bachelor’s thesis deals with the use of biomass for heating houses and apartment houses. The first part is dedicated to biomass. Here are mentioned the possibility of energy recovery, treatment and transformation of biomass into a form suitable for burning, its properties and combustion process itself. The second part is devoted to biomass boilers, their separation and description. The last section compares the specific biomass boiler with a boiler to natural gas, particularly from an economi...

  7. Corrosion/94 conference papers

    International Nuclear Information System (INIS)

    The approximately 500 papers from this conference are divided into the following sections: Rail transit systems--stray current corrosion problems and control; Total quality in the coatings industry; Deterioration mechanisms of alloys at high temperatures--prevention and remediation; Research needs and new developments in oxygen scavengers; Computers in corrosion control--knowledge based system; Corrosion and corrosivity sensors; Corrosion and corrosion control of steel reinforced concrete structures; Microbiologically influenced corrosion; Practical applications in mitigating CO2 corrosion; Mineral scale deposit control in oilfield-related operations; Corrosion of materials in nuclear systems; Testing nonmetallics for life prediction; Refinery industry corrosion; Underground corrosion control; Mechanisms and applications of deposit and scale control additives; Corrosion in power transmission and distribution systems; Corrosion inhibitor testing and field application in oil and gas systems; Decontamination technology; Ozone in cooling water applications, testing, and mechanisms; Corrosion of water and sewage treatment, collection, and distribution systems; Environmental cracking of materials; Metallurgy of oil and gas field equipment; Corrosion measurement technology; Duplex stainless steels in the chemical process industries; Corrosion in the pulp and paper industry; Advances in cooling water treatment; Marine corrosion; Performance of materials in environments applicable to fossil energy systems; Environmental degradation of and methods of protection for military and aerospace materials; Rail equipment corrosion; Cathodic protection in natural waters; Characterization of air pollution control system environments; and Deposit-related problems in industrial boilers. Papers have been processed separately for inclusion on the data base

  8. Engineering development of advanced coal-fired low emission boiler systems. Fourth quarterly technical progress report, July 1993--September 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    The LEBS plant design will be based on a high-sulfur Illinois No. 6 coal. This coal meets program selection requirements of extensive reserves and production, sulfur content, and representativeness. Two alternate test coals have been selected to examine fuel effects, and to broaden the range of application of the technology being developed. The alternate coals are a medium sulfur, Pittsburgh No. 8 bituminous, and a Wyoming subbituminous coal. The efficiency goals for the LEBS are challenging, particularly with the demands environmental controls are likely to place on auxiliary power. Table 1 shows estimates of overall plant efficiencies for three steam cycles: (1) a 2400 psi subcritical single reheat cycle typical of current plants; (2) a 3500 psi supercritical single reheat cycle; and (3) an advanced 4500 psi double reheat cycle. The plant heat rates are based on maximum boiler efficiency and minimum auxiliary power requirements consistent with conventional plant design for the design and alternate coals. The aggressive efficiency goals clearly require advanced steam conditions, as well as careful management of any added auxiliary power requirements for environmental controls. The EPRI SOAPP (State-of-the-Art Power Plant) project has selected the 4500 psi cycle as maximizing plant efficiency while minimizing generating costs for a commercial plant to be constructed by the year 2000. This program will incorporate the SOAPP base case cycle. The LESS design will incorporate a high-efficiency, once-through boiler design known as the Benson. Significant improvements in availability and operating flexibility have made this boiler design the system of choice for European power generation over the last fifteen years.

  9. DOE-DARPA High-Performance Corrosion-Resistant Materials (HPCRM), Annual HPCRM Team Meeting & Technical Review

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, J; Brown, B; Bayles, B; Lemieux, T; Choi, J; Ajdelsztajn, L; Dannenberg, J; Lavernia, E; Schoenung, J; Branagan, D; Blue, C; Peter, B; Beardsley, B; Graeve, O; Aprigliano, L; Yang, N; Perepezko, J; Hildal, K; Kaufman, L; Lewandowski, J; Perepezko, J; Hildal, K; Kaufman, L; Lewandowski, J; Boudreau, J

    2007-09-21

    The overall goal is to develop high-performance corrosion-resistant iron-based amorphous-metal coatings for prolonged trouble-free use in very aggressive environments: seawater & hot geothermal brines. The specific technical objectives are: (1) Synthesize Fe-based amorphous-metal coating with corrosion resistance comparable/superior to Ni-based Alloy C-22; (2) Establish processing parameter windows for applying and controlling coating attributes (porosity, density, bonding); (3) Assess possible cost savings through substitution of Fe-based material for more expensive Ni-based Alloy C-22; (4) Demonstrate practical fabrication processes; (5) Produce quality materials and data with complete traceability for nuclear applications; and (6) Develop, validate and calibrate computational models to enable life prediction and process design.

  10. [Engineering development of advanced coal-fired low-emission boiler systems]. Technical progress report, October--December 1995

    Energy Technology Data Exchange (ETDEWEB)

    Wesnor, J.D.; Bakke, E. [ABB Environmental Systems, Birmingham, AL (United States); Bender, D.J.; Kaminski, R.S. [Raytheon Engineers and Constructors, Inc., Philadelphia, PA (United States)

    1995-12-31

    The overall objective of the Project is the expedited commercialization of advanced coal-fired low-emisssion boiler systems. The primary objectives are: NO{sub x} emissions, lb/million Btu; SO{sub 2} emissions, lb/million Btu; particulate emissions, lb/million Btu; and net plant efficiency, not less than 42%. The secondary objectives are: improved ash disposability; reduced waste generation; and reduced air toxics emissions. Accomplishments to date are summarized for the following tasks: task 1, project planning and management; task 7, component development and optimization; task 8, preliminary POC test facility design; task 9, subsystem test design and plan; task 10, subsystem test unit construction; and task 11, subsystem test operation and evaluation.

  11. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-12-31

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

  13. Technical Basis Document No. 6: Waste Package and Drip Shield Corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, J; Pasupathi, V; Nair, P; Gordon, G; McCright, D; Gdowski, G; Carroll, S; Steinborn, T; Summers, T; Wong, F; Rebak, R; Lian, T; Ilevbare, G; Lee, J; Hua, F; Payer, J

    2003-08-01

    The waste package and drip shield will experience a wide range of interactive environmental conditions and degradation modes that will determine the overall performance of the waste package and repository. The operable modes of degradation are determined by the temperature regime of operation (region), and are summarized here. Dry-Out Region (T {ge} 120 C; 50 to 400 Years): During the pre-closure period, the waste package will be kept dry by ventilation air. During the thermal pulse, heat generated by radioactive decay will eventually increase the temperature of the waste package, drip shield and drift wall to a level above the boiling point, where the probability of seepage into drifts will become insignificant. Further heating will push the waste package surface temperature above the deliquescence point of expected salt mixtures, thereby preventing the formation of deliquescence brines from dust deposits and humid air. Phase and time-temperature-transformation diagrams predicted for Alloy 22, and validated with experimental data, indicates no significant phase instabilities (LRO and TCP precipitation) at temperatures below 300 C for 10,000 years. Neither will dry oxidation at these elevated temperatures limit waste package life. After the peak temperature is reached, the waste package will begin to cool, eventually reaching a point where deliquescence brine formation may occur. However, corrosion testing of Alloy 22 underneath such films has shown no evidence of life-limiting localized corrosion. Transition Region (120 C {ge} T {ge} 100 C; 400 to 1,000 Years): During continued cooling, the temperature of the drift wall will drop to a level close to the boiling point of the seepage brine, thus permitting the onset of seepage. Corrosion in a concentrated, possibly aggressive, liquid-phase brine, evolved through evaporative concentration, is possible while in this region. However, based upon chemical divide theory, most ({ge} 99%) of the seepage water entering the

  14. Mechanism of anaerobic (microbial) corrosion. Technical summary report No. 1, 1 Jun-31 Dec 82

    Energy Technology Data Exchange (ETDEWEB)

    Iverson, W.P.; Olson, G.J.

    1982-12-01

    This report in the form of three papers describes research into the role of bacteria in anaerobic corrosion processes. During the year we have given more evidence for a novel mechanism of anaerobic corrosion in which a volatile, highly reactive phosporous compound is produced as a result of the activities of sulfate-reducing bacteria (Desulfovibio desuluricans). The corrosion product is an amorphous type of iron phosphide which can be detected by the formation of phosphine upon its acidification. Phosphine (in addition to H2S) has been detected from all the cases of suspected anaerobic corrosion (including tubercles from the inside of water pipes) examined so far. In examining the headspace over growing cultures of Desulfovibio to detect this volatile phosphorus containing compound, using a gas chromatograph (GC) with a flame photometric detector (FPD) specific for phosphorus and sulfur, two sulfur compounds, in addition to H2S, were detected and identified. These compounds, methylmercaptan, and dimethyldisulfide, were found to be relatively non-corrosive to iron under anaerobic conditions. No volatile phosphorus compounds were detected.

  15. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-03-31

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

  17. Development of technical solutions for optimizing the hydraulic and thermal process circuits of the P-90 heat-recovery boiler used as part of the PGU-450T combined-cycle plant at the severozapadnaya cogeneration station

    Science.gov (United States)

    Belyakov, I. I.; Breus, V. I.; Barannikov, A. B.

    2012-03-01

    Results from work on analyzing the performance of the P-90 heat-recovery boilers used as part of the PGU-450T-based Unit 1 at the Severozapadnaya cogeneration station and on revealing factors causing damage to the bends of evaporating tubes are presented. Technical solutions using which a V-94.2 gas turbine can be replaced by a GTE-160 gas turbine are considered.

  18. Life extension of boilers using weld overlay protection

    Energy Technology Data Exchange (ETDEWEB)

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

    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.

  19. Study of Dewpoint Corrosion of Coal-fired Boiler%燃煤锅炉露点腐蚀实验研究

    Institute of Scientific and Technical Information of China (English)

    张知翔; 张智超; 曳前进; 孙立岩; 连世泉; 郝宝乾; 赵钦新

    2012-01-01

    Based on the new type of device, widely used ND steel, Corten steel and 316L steel, compared with 20G steel and 20# steel, dewpoint corrosion was tested on a 600MW power plant in Inner Mongolia Datang International Tuoketuo Power Generation Co. ,Ltd. The temperature of inlet cycling water was 30-80℃ and the testing time was 72h. The scanning electron microscope (SEM) and energy dispersive spectrometer (EDS) were used to analyze the microstructure and the migration of the corrosive elements. The mechanism of dewpoint corrosion was revealed, and the relationship between the thickness of corrosion layer and temperature of inlet water was obtained. The results also showed that the order of corrosion resistance for the five materials was 316L>ND>Corten>20G>20# .%以新型实验装置为基础,以ND钢、Corten钢、316L钢作为研究对象,20G与20 #碳钢为对比材料,以内蒙古大唐国际托克托发电有限公司5#机组为实验平台进行露点腐蚀实验,实验中循环介质温度为30~80℃,实验时间为72h.利用扫描电镜(SEM)和能谱分析(EDS)探查腐蚀后各材料微观组织结构,揭示露点腐蚀机理;绘制各材料的腐蚀层厚度随壁温的变化曲线;结果表明:5种材料的耐硫酸露点腐蚀能力:316L> ND>Corten>20G>20#.

  20. 循环流化床锅炉生物质与煤混烧积灰腐蚀试验%Experimental study on ash deposition and corrosion in a CFB boiler co-firing biomass with coal

    Institute of Scientific and Technical Information of China (English)

    刘志; 雷秀坚; 汪佩宁; 胡康涛; 杨海瑞

    2015-01-01

    During ash decomposition and corrosion tests in a 75 t/h circulating fluidized bed (CFB)boiler burning coal and biomass,the corrosion probe equipped with three kinds of metal samples was placed in front of the superheater,and the superheater tube wall temperature was simulated with a system of air cooling.Three kinds of metal deposition samples were obtained in operating mode (duration time of 24 hours)with three mixing ratios of coal and biomass.The physicochemical property of the samples was ana-lyzed by SEM-EDX.The results show that,under the testing conditions,no deposition was found at the wind side,and the deposition formed at the lee side was different for different metallic materials.No materi-al loss or significant corrosion was detected.It is proved in this study that depositions at the lee side of the superheater were probably more serious than that at the wind side,and the co-combustion of coal and bio-mass containing low levels of alkali metal will not cause serious deposition or corrosion and can be applied in industrial production.%将3种不同金属管材样品环的气冷腐蚀探头置于某生物质与煤混烧的75 t/h 循环流化床(CFB)锅炉尾部烟道低温过热器前,通过空气冷却模拟过热器的管壁温度,获得3种混烧比例工况下(持续时间24 h)3种管材的积灰样品。利用扫描电子显微镜分析积灰的理化特性,探讨混烧比例和材料种类对积灰腐蚀的影响规律。结果表明:在测试工况下,样品环迎风面不存在明显积灰现象,而背风面积灰明显,且随着材料的不同而有所不同,但未发现明显腐蚀或金属磨损,表明碱金属含量相对较低的生物质与煤混烧并不会造成严重积灰及腐蚀。

  1. The atmospheric corrosion: an important technical-economic and nuclear safety factor during storage in the construction of nuclear power plants

    International Nuclear Information System (INIS)

    The purpose of this work is to show the results of the research performed to determine the atmospheric corrosion in the region of Juragua nuclear power plant and to offer some practical recommendations to increase the efficiency during the storage of materials, considering technical-economic and nuclear safety aspects

  2. Corrosion of Boiler Wall by Enriched Media%锅炉水冷壁介质浓缩腐蚀研究

    Institute of Scientific and Technical Information of China (English)

    霍金仙; 楼台芳; 吴玲

    2001-01-01

    The corrosion of wa-tercooled boder wall material by enriched media was investigated in autoclave. It showed that the compact film was formed on the specimen while no media enrichment occured the pitting corrosion appeared as the enrichment increasing while enrichment multiply power>1 000 the overall corrosion then occured. The preventive measures were dis-cussed.%在高压釜试验的基础上,研究了锅炉水冷壁介质浓缩腐蚀情况,并得出介质不发生浓缩时,正常形成氧化膜,膜质致密;当浓缩倍数小于15时,CI\\+-破坏氧化膜而发生点蚀;当浓缩倍数大于1 000时,PO3-4参与了成膜,发生全面腐蚀,研究并提出了预防措施。

  3. Corrosion of support materials

    International Nuclear Information System (INIS)

    Results from a heavily fouled 19 tube C-E model boiler test to investigate the potential for egg crate corrosion in aggressively fouled AVT chemistry are reported. Substantial support plate and egg crate corrosion was produced in this test. Carbon steel drilled support plates exhibited extensive denting which resulted in flow hole ligament cracking. Corrosion of the carbon steel egg crate, through-wall at areas of tube contact, resulted in denting of the Alloy 600 heat transfer tubes. Corrosion performance of the 409 stainless steel egg crate was improved compared to the carbon steel egg crate although localized through-wall corrosion was noted. The results from the above test and previously reported tests were compared based on the following simplifying assumptions: maximum dent size and/or corrosion penetrations utilized, average bulk water chloride concentrations, pilling bedworth ratios, pot and model boilers data are equivalent, heat flux not significantly variable, and plot is semi-quantitative. Conclusions based on plots of maximum corrosion rates as a function of average bulk water chloride concentrations are presented. Finally, the corrosion performance of the various materials of construction for support systems were ranked for each test. Final material selection for future support systems must be based on a balance of thermal/hydraulic, metallurgical, corrosion and design considerations

  4. PENCEGAHAN KOROSI DENGAN BOILER WATER TREATMENT (BWT PADA KETEL UAP KAPAL.

    Directory of Open Access Journals (Sweden)

    Suleman Suleman

    2012-03-01

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

  5. 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...... bricks in the boiler concept to each other and hereby obtain signicant reductions in the boiler concepts weight and foot-print . The actual development project has focused on an heavy fuel oil-red boiler for the marine market with a capacity in the range 1-10 t/h saturated steam. The development project...

  6. Independent Research and Design of 600-MW Supercritical CFB Boiler

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In order to further develop and improve the technologies for large-capacity supercritical CFB boiler, the key technologies for large CFB boiler were systematically studied, based on the development of first domestically-made 210-MW and 330-MW CFB boilers. The scheme of 600-MW supercritical CFB boiler was designed, including the furnace structure, key components, steam-water system and auxiliary systems, which laid a technical foundation for the engineering applications.

  7. Protective Coatings in the Power Boilers which are Used to Combust Waste – Surfacing Anticorrosive Layers

    Directory of Open Access Journals (Sweden)

    Słania J.

    2016-06-01

    Full Text Available General requirements and technological solutions of incinerating plants were presented. Heat processing of waste in fluidized and stoker-fired boilers were described. A problem of corrosion and the methods of preventing it in boilers used to combust waste were shown. Materials of increased resistance to corrosion used in power industry were characterised.

  8. Development of technical solutions on a coal-fired boiler for a power plant unit of 800 MW with steam parameters of 35 MPa and 700/720°C

    Science.gov (United States)

    Shvarts, A. L.; Verbovetsky, E. Kh.; Somova, E. V.; Smolin, A. V.

    2015-12-01

    Development of a coal-fired boiler for a power plant unit of 800 MW with advanced ultra-supercritical steam parameters of 35 MPa and 700/720°C is presented. The main technical solutions providing the reliability, profitability, and low emissions of harmful substances in the atmosphere are given. The fuel is the black coal of (Taldinskoye field, Kuznetsk basin). The gross efficiency of the boiler is 94%. The U-shaped configuration of a boiler is chosen, which allows the reduction of the capital expenditure for steam turbine piping made of expensive nickel alloys. The horizontal connection flue of the boiler, where the primary and reheat steam screens are located, is equipped with two cold funnels. The upper section of the convection shaft is separated with a vertical screen wall into two parallel "split tail" flues, which allows one to control the reheat steam temperature by redistributing the flue gas between the gas flues. The URS screens are two-stage with a lifting motion of the medium and a partial bypassing of the first stage. The lower radiant section is two-stage. To reduce the temperature of screen walls at the fire chamber outlet, the lowering motion of the working medium and combustion gases is used. The hydrodynamics of the screens with the lowering motion of the medium for preventing the aperiodic instability in the start regimes is analyzed. Besides the stepwise combustion of coal dust providing the improved environmental parameters, the boiler plant is equipped with a selective catalytic reduction (SCR) system, an ash collector (an electric filter combined with a filter bag), and a desulphurization device.

  9. 锅炉水冷壁管氢腐蚀爆管原因分析%Cause Analysis of Hydrogen Corrosion Induced Bursting of Waterwall Tubes in a Boiler

    Institute of Scientific and Technical Information of China (English)

    张亚明; 夏邦杰; 董爱华

    2012-01-01

    某热电厂5号锅炉水冷壁发生爆管.对取样水冷壁管进行了宏观观察、化学分析、金相分析、扫描电镜与电子能谱分析及x射线衍射分析等.结果表明,爆管原因是水冷壁管向火侧内壁局部区域发生氢腐蚀所致.提出了预防此类事故发生的措施.%Bursting failure occurred on waterwall tubes of No.5 boiler in a power plant. Macroscop- ic inspection, chemical analysis, metallurgraphy, scanning electron microscopy (SEM), energy dis-persive spectroscopy (EDS) and X-ray diffraction (XRD) were adopted to examine the failed tube. The results indicated that the tube rupture was resulted from localized hydrogen corrosion of the part facing fire. Preventive measures of such failures are put forward.

  10. Engineering development of advanced coal-fired low-emission boiler systems. Technical progress report No. 10, January 1995--March 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-17

    The project is on schedule and under budget. The current status is shown in the Milestone Schedule Report included as Appendix A. All Project Plans were updated based on the revised finding level authorized for FY95 and anticipated for FY96. Technology Transfer activities included {open_quotes}supplying{close_quotes} three executives and several team members to the LEBS Workshop, delivering a technical paper at a conference, and working on a Combustion 2000 Session for another conference. ABBES and CeraMem reached agreement concerning Task 7 work, including ownership and disposition of project-purchased equipment to be used during Task 7 and also during Task 11. A test plan was prepared. Task 7 activities for the Low-NO{sub x} Firing System included computational modeling of the firing arrangement. Reasonable comparisons to experimental data previously obtained in the Boiler Simulation Facility were achieved. A kinetic evaluation for both baseline and low NO{sub x} firing arrangements was also performed, with results indicating that the final reducing zone within the main windbox has a dominant effect on NO{sub x} reduction, with higher temperatures being more favorable for lower NO{sub x}. A week of combustion testing was completed in the Fundamental Scale Burner Facility to examine the impact of integrated fuel staging (NO{sub x} reduction via the reburn mechanism), and to explore preliminary vertical staging concepts within the main windbox region. Preliminary results from this testing demonstrated the potential of vertical air staging within the main windbox to augment overfire air. Testing was performed to quantify the coal size distribution and power requirements for one (1) conventional static and four (4) dynamic classifier designs. Results from this testing show the dynamic classifier capable of producing finer grinds of coal at lower relative power requirements.

  11. Technical - economical opportunity of replacing rubber coated steel in tubes and reinforcements by polyethylene of high density for corrosive media

    International Nuclear Information System (INIS)

    The polyethylene of high density, PEHD, is currently used for methane gas, drinking water (hot and cool) tube systems as well as for interior and exterior installations for domestic and industrial consumers. In this paper one proposes an extension of the range of PEHD utilizations to irrigation grids, transport and distribution of the food and industrial liquids, for coating the optical fibres, replacing the systems of tubes with anti corrosive properties (stainless steels, carbon steels coated with rubber), protection of hot fluid transport tubes, fire extinguishers, etc.). To evidence the advantages of replacing the rubber coated steel tubing by PEHD tubes a comparative technical-economical thorough analysis was conducted in the Heavy Water Plant . The paper presents: - the PEHD, a thermoplastic material for fluid transport under pressure; - physico-chemical and mechanical properties of the PEHD products; - types of characteristic dimensions of the PEHD products; - techniques of joining used in mounting PEHD grids; - tools and devices used in welding. Presented are the general properties and computing elements for tubes, assembling procedures, testing and quality control in the mountings of PEHD tube systems. In conclusion, using PEHD in the fields mentioned is advantageous from both technical and economical point of view as compared with rubber coated tubing

  12. Microphone Detects Boiler-Tube Leaks

    Science.gov (United States)

    Parthasarathy, S. P.

    1985-01-01

    Unit simple, sensitive, rugged, and reliable. Diaphragmless microphone detects leaks from small boiler tubes. Porous plug retains carbon granules in tube while allowing pressure changes to penetrate to granules. Has greater life expectancy than previous controllers and used in variety of hot corrosive atmospheres.

  13. Deposition and high temperature corrosion in a 10 MW straw

    DEFF Research Database (Denmark)

    Michelsen, Hanne Philbert; Frandsen, Flemming; Dam-Johansen, Kim;

    1998-01-01

    Deposition and corrosion measurements were conducted at a 10 MW wheat straw fired stoker boiler used for combined power and heat production. The plant experiences major problems with deposits on the heat transfer surfaces, and test probes have shown enhanced corrosion due to selective corrosion...... formation and selective corrosion are discussed based on the results of the practical measurements....

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2000-05-01

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

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

    OpenAIRE

    Gajić Anto S.; Tomić Milorad V.; Pavlović Ljubica J.; Pavlović Miomir G.

    2010-01-01

    This paper presents sources and types of corrosion processes of boiler tube system of the Thermal Power Plant "Ugljevik". The main goal in the electric power production is to achieve lower prices, which can only be done by providing low maintenance costs. While it is not possible to completely stop corrosion, it could be slowed down and it's effects could be reduced. In order to reduce corrosion to a minimum on thermal power plants' vital equipment, particularly boilers, it is necessary to de...

  16. Technical and economic comparison between two processes respectively using different water sources as boiler makeup water%不同锅炉补给水水源的技术经济比较

    Institute of Scientific and Technical Information of China (English)

    李少杰

    2012-01-01

    针对直接使用地表水与利用循环冷却水系统的排水作为火力发电厂锅炉补给水进行技术经济比较,为电厂合理选择适合的锅炉补给水处理水源作参考.研究结果表明,项目采用地表水做水源的方案电耗低、基建费用低、制水成本低、自动化程度高、运行及管理方便、检修维护工作量小,但水耗指标略差.从经济、技术、环保等方面进行综合考虑,推荐采用地表水作为锅炉补给水水源.%The technical and economic comparison between the two processes respectively using surface water and drainage from circulating cooling water system as boiler makeup water was carried out, which provided a reference for power plants selecting source of makeup water for their boilers. The results of the study showed that, using surface water as boiler makeup water had advantages of low power consumption, low capital construction cost, low water producing cost; high degree of automation, convenient for operation and management, small repair and maintenance workload, however, its water consumption was relatively large. Based on the comprehensive consideration from aspects of economy, technology, environmental protection and so on, surface water was finally recommened as a proper source of boiler makeup water.

  17. Superclean coal-water slurry combustion testing in an oil-fired boiler. Semiannual technical progress report, August 15, 1991--February 15, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Miller, B.G.; Poe, R.L.; Morrison, J.L.; Xie, Jianyang; Walsh, P.M.; Schobert, H.H.; Scaroni, A.W.

    1992-05-29

    The Pennsylvania State University is conducting a superclean coal-water slurry (SCCWS) program for the United States Department of Energy (DOE) and the Commonwealth of Pennsylvania with the objective of determining the capability of effectively firing SCCWS in an industrial boiler designed for oil. Penn State has entered into a cooperative agreement with DOE to determine if SCCWS (a fuel containing coal with less than 3.0 wt.% ash and 0.9 wt.% sulfur) can effectively be burned in an oil-designed industrial boiler without adverse impact on boiler rating, maintainability, reliability, and availability. The project will provide information on the design of new systems specifically configured to fire these clean coal-based fuels.

  18. 对冲燃烧锅炉水冷壁高温腐蚀运行调整%Operation adj ustment for high temperature corrosion in water wall of supercritical opposed firing boiler

    Institute of Scientific and Technical Information of China (English)

    周科; 佘园元; 鲁芬; 李建设; 陈俊彬

    2016-01-01

    Due to the strong reducing atmosphere and H2S formation around the water wall of a supercritical opposed firing boiler,serious high temperature corrosion occurred in the water walls.To solve this prob-lem,the single factor alternate method was applied to experimentally investigate the effects of main operat-ing parameters on H2 S concentrations around side water wall.The results show that,on the basis of cus-tomary boiler operating condition,after a series of regulations,such as weakening the tertiary air swirl of the main burner appropriately,distributing the tertiary air flow as bowl type,strengthening the secondary air swirl of the main burner appropriately,increasing the swirling air ratio of the OFA burner,reducing di-rect air ratio of the OFA burner,increasing the running oxygen concentration appropriately,distributing the mills output uniformly,increasing the primary air velocity appropriately,and reducing the coal fineness, the H2 S concentration around the side water wall decreased from 876.5 mg/m3 to 352.2 mg/m3 .The at-mosphere around the water wall surface was greatly improved,and the security of the boiler operation was enhanced.%某超临界机组对冲燃烧锅炉水冷壁存在严重高温腐蚀的现象,这主要因水冷壁壁面附近存在强还原性气氛并伴有 H2 S气体产生所致.本文采用单因素轮换法,试验研究了主燃烧器的三次风旋流强度、三次风风量、二次风旋流强度、二次风风量等主要运行参数调整对锅炉水冷壁壁面气氛特性参数 H2 S质量浓度的影响规律.结果表明,在锅炉习惯运行方式的基础上,通过适当削弱主燃烧器三次风旋流,同层燃烧器三次风采取“碗式配风”,适当增强主燃烧器二次风旋流,增加燃尽风二次风风量,减少燃尽风一次风风量,适当提高运行氧量和一次风速,采取均等配煤方式,降低煤粉细度后,水冷壁侧墙平均H2 S质量浓度由876.5 mg/m3降至352.2 mg/m3,水冷壁壁

  19. Fundamental studies of the mechanisms of slag deposit formation: Studies on initiation, growth and sintering in the formation of utility boiler deposits: Topical technical report

    Energy Technology Data Exchange (ETDEWEB)

    Tangsathitkulchai, M.; Austin, L.G.

    1986-03-01

    Three laboratory-scale devices were utilized to investigate the mechanisms of the initiation, growth and sintering process involved in the formation of boiler deposits. Sticking apparatus investigations were conducted to study deposit initiation by comparing the adhesion behavior of the ash drops on four types of steel-based heat exchanger materials under the conditions found in a utility boiler and an entrained slagging gasifier. In addition, the adhesion behavior of the ash drops on a reduced steel surface were investigated. All the ash drops studied in this investigation were produced from bituminous coals.

  20. Steam boiler technology

    Energy Technology Data Exchange (ETDEWEB)

    Teir, S.

    2002-07-01

    The steam boiler technology e-Book is provided by the Laboratory of Energy Engineering and Environmental Protection at Helsinki University of Technology. The book covers the basics and the history of steam generation, modern boilers types and applications, steam/water circulation design, feedwater and steam systems components, heat exchangers in steam boilers, boiler calculations, thermal design of heat exchangers.

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

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Bradley; Davis, Kevin; Senior, Constance; Shim, Hong Shim; Otten, Brydger; Fry, Andrew; Wendt, Jost; Eddings, Eric; Paschedag, Alan; Shaddix, Christopher; Cox, William; Tree, Dale

    2013-09-30

    ) Assessment of oxy-combustion impacts in two full-scale coal-fired utility boiler retrofits based on computational fluid dynamics (CFD) modeling of air-fired and oxygen-fired operation. This research determined that it is technically feasible to retrofit the combustion system in an air-fired boiler for oxy-fired operation. The impacts of CO{sub 2} flue gas recycle and burner 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) were minimal, with the exception of high sulfur levels resulting from untreated flue gas recycle with medium and high-sulfur coals. This work focused on combustion in the radiant and convective sections of the boiler and did not address boiler system integration issues, plant efficiencies, impacts on downstream air pollution control devices, or CO{sub 2} capture and compression. The experimental data, oxy-firing system principles and oxy-combustion process mechanisms provided by this work can be used by electric utilities, boiler OEMs, equipment suppliers, design firms, software vendors, consultants and government agencies to assess retrofit applications of oxy-combustion technologies to existing boilers and to guide development of new designs.

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

    International Nuclear Information System (INIS)

    This is the seventh 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 co-funding for this program. This program contains multiple tasks and good progress is being made on all fronts. A series of field tests for RRI at the Ameren Sioux Unit No.1 have demonstrated that RRI can provide up to 30% NOx reduction over the use of over fire air in large scale (480MW) cyclone fired utility boilers. The field tests and modeling results are in good agreement. Final data analysis has been completed for tests performed at Eastlake Power Station of a real-time waterwall corrosion monitoring system. The tests demonstrated that corrosion could be measured accurately in real-time in normal boiler operations, and an assessment of waterwall wastage could be made without impacting boiler availability. Detailed measurements of soot volume fraction have been performed for a coal burner in a pilot scale test furnace. The measured values are in good agreement with the expected trends for soot generation and destruction. Catalysts from four commercial manufacturers have been ordered and one of the samples was received this quarter. Several in situ analyses of vanadium-based SCR catalyst systems were completed at BYU. Results to date indicate that the system produces results that represent improvements compared to literature examples of similar experiments. Construction of the catalyst characterization system (CCS) reactor is nearly complete, with a few remaining details discussed in this report. A literature review originally commissioned from other parties is being updated and will be made available under separate cover as part of this investigation. Fabrication of the multi-catalyst slipstream

  3. 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.

  4. 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. PMID:23552243

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2003-06-30

    This is the twelfth Quarterly Technical Report for DOE Cooperative Agreement No: DE-FC26-00NT40753. The goal of the project is to develop cost effective analysis tools and techniques for demonstrating and evaluating low NOx control strategies and their possible impact on boiler performance for boilers firing US coals. The Electric Power Research Institute (EPRI) is providing co-funding for this program. This program contains multiple tasks and good progress is being made on all fronts. During this quarter, a new effort was begun on the development of a corrosion management system for minimizing the impacts of low NOx combustion systems on waterwalls; a kickoff meeting was held at the host site, AEP's Gavin Plant, and work commenced on fabrication of the probes. FTIR experiments for SCR catalyst sulfation were finished at BYU and indicated no vanadium/vanadyl sulfate formation at reactor conditions. Improvements on the mass-spectrometer system at BYU have been made and work on the steady state reactor system shakedown neared completion. The slipstream reactor continued to operate at AEP's Rockport plant; at the end of the quarter, the catalysts had been exposed to flue gas for about 1000 hours. Some operational problems were addressed that enable the reactor to run without excessive downtime by the end of the quarter.

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

    Energy Technology Data Exchange (ETDEWEB)

    Mike Bockelie; Kevin Davis; Martin Denison; Connie Senior; Hong-Shig Shim; Darren Shino; Dave Swenson; Larry Baxter; Calvin Bartholomew; William Hecker

    2005-06-30

    This is the twentieth Quarterly Technical Report for DOE Cooperative Agreement No: DEFC26-00NT40753. The goal of the project is to develop cost-effective analysis tools and techniques for demonstrating and evaluating low-NO{sub x} control strategies and their possible impact on boiler performance for boilers firing US coals. The Electric Power Research Institute (EPRI) is providing co-funding for this program. At the beginning of this quarter, the corrosion probes were removed from Gavin Station. Data analysis and preparation of the final report continued this quarter. This quarterly report includes further results from the BYU catalyst characterization lab and the in-situ FTIR lab, and includes the first results from tests run on samples cut from the commercial plate catalysts. The SCR slipstream reactor at Plant Gadsden was removed from the plant, where the total exposure time on flue gas was 350 hours. A computational framework for SCR deactivation was added to the SCR model.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2004-04-01

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

  8. Engineering development of advanced coal-fired low-emission boiler systems. Quarterly technical progress report, January 1--March 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-28

    This project is concerned with the development of an a coal-fired low-emission boiler system. During march, separate kick-off meetings were held with PSI Powerserve, Raytheon and B&W`s Environmental Equipment Division to begin work on Phase I Task 5, the Commercial Plant Design. In addition, a meeting was held with MIT to discuss and review work completed and schedule work remaining on the project.

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-19

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

  10. Review of conditions for reliable boiler operation; Bedingungen fuer einen zuverlaessigen Kesselbetrieb

    Energy Technology Data Exchange (ETDEWEB)

    Stodola, J.

    1999-08-01

    This paper discusses fundamentals of corrosion protection in boilers, different boiler water treatments used by the utility industry to achieve this objective as well as limitations boiler designs may impose on long term boiler performance. The purpose there is to determine whether chemists have the ability to guarantee reliable and problem free operation of any boiler. (orig.) [German] Dieser Artikel diskutiert die Grundlagen des Korrosionsschutzes in Kesseln, die verschiedenen von den Kraftwerken angewandten Kesselwasser-Fahrweisen und die Auswirkung der Kesselauslegung auf das langfristige Kesselverhalten. Es wird ueberlegt, ob Chemiker einen zuverlaessigen und problemfreien Betrieb eines jeden Kessels garantieren koennen. (orig.)

  11. High temperature corrosion during waste incineration : characterisation, causes and prevention of chlorine-induced corrosion

    OpenAIRE

    Viklund, Peter

    2011-01-01

    Waste-fired boilers suffer severely from corrosion of critical components such as superheater tubes. In this work the high temperature corrosion of candidate superheater alloys have been investigated by detailed laboratory studies and controlled field exposures in full-scale boilers. In a laboratory study the detrimental effect of gaseous hydrochloric acid (HCl) on three  different ground surface and preoxidised austenitic stainless steels was investigated. Exposures were conducted in an envi...

  12. Technical retrofit of low Nox combustion for first 600 MW opposed firing boiler in China%国内首台600MW对冲燃烧锅炉低NOx燃烧技术改造

    Institute of Scientific and Technical Information of China (English)

    屠小宝; 胡伟锋; 徐良; 徐仲雄; 戴成峰; 应明良

    2011-01-01

    In order to minimize the possible negative effect after boiler low NOx combustion technical retrofit, the design optimization for staged combustion of main burner was emphasized, the larger chemical equivalent proportion of main burning area was adopted, the sensitivity and the dependence of chemical equivalent proportion of main burning area were reduced, and the heating surface was adjusted and rotating classifier for mill was installed in burner retrofit design. After the retrofit, the overall performance of the boiler achieves the expected goals and the NOx reduction rate reaches to 50%.%为将锅炉低NOx燃烧技术改造可能产生的负面影响减至最低程度,在燃烧器改造设计中,注重对主燃烧器分级燃烧的设计优化,采用较大的主燃烧区化学当量比,降低对主燃烧区低化学当量比的依赖度和敏感度,同时采取受热面调整和磨煤机增装动态分离器等配套措施.改造后锅炉总体性能良好,NOx减排幅度达到50%.

  13. Innovative Clean Coal Technology (ICCT): 500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Technical progress report, fourth quarter 1991

    Energy Technology Data Exchange (ETDEWEB)

    1992-04-21

    This quarterly report discusses the technical progress of an Innovative Clean Coal Technology (ICCT) demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. The project is being conducted at Georgia Power Company`s Plant Hammond Unit 4 located near Rome, Georgia. The primary goal of this project is the characterization of the low NO{sub x} combustion equipment through the collection and analysis of long-term emissions data. A target of achieving fifty percent NO{sub x} reduction using combustion modifications has been established for the project. The project provides a stepwise retrofit of an advanced overfire air (AOFA) system followed by low NO{sub x} burners (LNB). During each test phase of the project, diagnostic, performance, long-term, and verification testing will be performed. These tests are used to quantify the NO{sub x} reductions of each technology and evaluate the effects of those reductions on other combustion parameters such as parameters such as particulate characteristics and boiler efficiency.

  14. 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

  15. 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

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

    Directory of Open Access Journals (Sweden)

    Gajić Anto S.

    2010-01-01

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

  17. 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.

  18. Boilers, evaporators, and condensers

    International Nuclear Information System (INIS)

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

  19. Central heating: package boilers

    Energy Technology Data Exchange (ETDEWEB)

    Farahan, E.

    1977-05-01

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

  20. 500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Technical progress report, second quarter 1994, April 1994--June 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    This quarterly report discusses the technical progress of an Innovative Clean Coal Technology (ICCT) demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NOx) emissions from coal-fired boilers. The project is being conducted at Georgia Power Company`s Plant Hammond Unit 4 located near Rome, Georgia. The primary goal of this project is the characterization of the low NOx combustion equipment through the collection and analysis of long-term emissions data. A target of achieving fifty percent NOx reduction using combustion modifications has been established for the project. The project provides a stepwise retrofit of an advanced overfire air (AOFA) system followed by low NOx burners (LNB). During each test phase of the project, diagnostic, performance, long-term, and verification testing will be performed. These tests are used to quantify the NOx reductions of each technology and evaluate the effects of those reductions on other combustion parameters. Results are described.

  1. Analysis of Causes for Corrosion of Tube Bundle Welded Joint of Waste Heat Boiler in Ammonia Synthesis System and Improvement%氨合成系统废热锅炉管束焊接接头腐蚀原因分析及改进

    Institute of Scientific and Technical Information of China (English)

    张英杰; 韩荣芹; 左卫锋

    2013-01-01

    氨合成系统废热锅炉投运8个月后,其管束的气体进口端联箱管与换热管间的焊接接头出现连续点状腐蚀坑样缺陷,而管束的气体出口端相应位置没有出现此类缺陷,设备其他部位未见异常.通过对氨合成系统废热锅炉管束焊接接头腐蚀部位的宏观形貌、低倍形态、化学组分、扩展方向及金相组织等特征进行分析,判定腐蚀形态为电偶腐蚀.针对腐蚀形态,采取了相应的改进措施,取得了明显的效果.%8 months after putting into operation of the waste heat boiler in ammonia synthesis system,defects of continuous dotted etch pit appeared at welded joints between gas inlet connecting tube and heat exchange tube of tube bundle,while no such kind of defect found at relevant position of gas outlet of tube bundle,and there are no troubles seen in other parts of the equipment.Through analyzing features of micro profile,macroscopic appearance,chemical composition,extension direction and metallographic structure,etc.of corroded parts of the tube bundle welded joints of the waste heat boiler in ammonia synthesis system,it is determined that the corrosion form is galvanic corrosion.In connection with the corrosion form,relevant improvement measures are taken and significant effect is obtained.

  2. Boiler Retrofit for the Utilization of Biodiesel

    Directory of Open Access Journals (Sweden)

    Leily Nurul Komariah

    2016-02-01

    Full Text Available Fuel oil used in the boiler is able to substitute with biodiesel. In lower blends, there are no engine modification needed, but some researchers recommended some technical adjustments in order to maintain the boiler's performance and equipment durability. This study consists of the comparison between the performance of boiler before and after retrofitting on the use of biodiesel. The diesel oil was introduced in biodiesel blends of 10% (B10, 20% (B20 and 25% (B25. A fire tube boiler was used for the test with pressure of 3 bar and heat input capacity of 60,000 kcal. The boiler retrofit is conducted by fine tuning the fan damper scale (FDS and adding a heating feature on fuel system. It was specifically intended to maintain the quality of combustion and boiler efficiency as well as to avoid an increase in fuel consumption. The combustion behaviour was monitored by exhaust emissions of CO, NOx, and SO2. The fan damper scale (FDS and fuel temperature is adjusted by the increasing portion of biodiesel used. The fuel heating apparatus was set at temperature of 40oC for the use of B10, and 60oC for B20 and B25. The FDS adjustment was successfully resulted a reduction in rate of combustion air by average of 9.2%. The boiler retrofitting for the utilization of B10, B20 and B25 showed an increase in boiler efficiency by 0.64%, 0.42% and 2.6% respectively. The boiler retrofitting is surprisingly reduced the fuel consumption by average of 11.2%.

  3. Engineering development of advanced coal-fired low-emission boiler systems: Technical progress report No. 16, July-September 1996

    Energy Technology Data Exchange (ETDEWEB)

    Barcikowski, G.F.; Borio, R.W.; Bozzuto, C.R.; Burr, D.H.; Cellilli, L.; Fox, J.D.; Gibbons, T.B.; Hargrove, M.J.; Jukkola, G.D.; King, A.M.

    1996-11-27

    The overall objective of the Project is the expedited commercialization of advanced coal-fired low-emission boiler systems. The Project is under budget and generally on schedule. The current status is shown in the Milestone Schedule Status Report included as Appendix A. Under Task 7--Component development and optimization, the CeraMem filter testing was completed. Due to an unacceptably high flue gas draft loss, which will not be resolved in the POCTF timeframe, a decision was made to change the design of the flue gas cleaning system from Hot SNO{sub x}{sup {trademark}} to an advanced dry scrubber called New Integrated Desulfurization (NID). However, it is recognized that the CeraMem filter still has the potential to be viable in pulverized coal systems. In Task 8-- Preliminary POCTF design, integrating and optimizing the performance and design of the boiler, turbine/generator and heat exchangers of the Kalina cycle as well as the balance of plant design were completed. Licensing activities continued. A NID system was substituted for the SNO{sub x} Hot Process.

  4. Evaluation of corrosion attack of chimney liners

    OpenAIRE

    Blahetová M.; Horák J.; Kubesa P.; Lasek S.; Ochodek T.

    2016-01-01

    The case study of chimney liner corrosion addresses three specific cases of damage of chimney systems from of stainless steels. These systems were used for flue of gas arising from the combustion of brown coal in small automatic boilers, which are used for heating. Detailed analyzes implied that the cause of devastating corrosion of the steel AISI 316 and 304 steel (CSN 17349, 17241) was particularly high content of halides (chlorides and fluorides), which caused a severe pitting corrosion, w...

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

    DEFF Research Database (Denmark)

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

    In this literature report is provided a status for the present knowledge level on ash properties when co-firing coal and biomass. The fly ash formed in boilers using co-firing of coal and straw do have a large influence on ash deposit formation, boiler corrosion, fly ash utilization and operation...

  6. 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.

  7. 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 Suuberg; Eric Eddings; Larry Baxter

    2002-01-31

    This is the sixth 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 co-funding for this program. This program contains multiple tasks and good progress is being made on all fronts. Preliminary results from laboratory and field tests of a corrosion probe to predict waterwall wastage indicate good agreement between the electrochemical noise corrosion rates predicted by the probe and corrosion rates measured by a surface profilometer. Four commercial manufacturers agreed to provide catalyst samples to the program. BYU has prepared two V/Ti oxide catalysts (custom, powder form) containing commercially relevant concentrations of V oxide and one containing a W oxide promoter. Two pieces of experimental apparatus being built at BYU to carry out laboratory-scale investigations of SCR catalyst deactivation are nearly completed. A decision was made to carry out the testing at full-scale power plants using a slipstream of gas instead of at the University of Utah pilot-scale coal combustor as originally planned. Design of the multi-catalyst slipstream reactor was completed during this quarter. One utility has expressed interest in hosting a long-term test at one of their plants that co-fire wood with coal. Tests to study ammonia adsorption onto fly ash have clearly established that the only routes that can play a role in binding significant amounts of ammonia to the ash surface, under practical ammonia slip conditions, are those that must involve co-adsorbates.

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

    International Nuclear Information System (INIS)

    This is the sixth 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 co-funding for this program. This program contains multiple tasks and good progress is being made on all fronts. Preliminary results from laboratory and field tests of a corrosion probe to predict waterwall wastage indicate good agreement between the electrochemical noise corrosion rates predicted by the probe and corrosion rates measured by a surface profilometer. Four commercial manufacturers agreed to provide catalyst samples to the program. BYU has prepared two V/Ti oxide catalysts (custom, powder form) containing commercially relevant concentrations of V oxide and one containing a W oxide promoter. Two pieces of experimental apparatus being built at BYU to carry out laboratory-scale investigations of SCR catalyst deactivation are nearly completed. A decision was made to carry out the testing at full-scale power plants using a slipstream of gas instead of at the University of Utah pilot-scale coal combustor as originally planned. Design of the multi-catalyst slipstream reactor was completed during this quarter. One utility has expressed interest in hosting a long-term test at one of their plants that co-fire wood with coal. Tests to study ammonia adsorption onto fly ash have clearly established that the only routes that can play a role in binding significant amounts of ammonia to the ash surface, under practical ammonia slip conditions, are those that must involve co-adsorbates

  9. Boiler system lay-up; Avstaellning och konservering av pannanlaeggningar

    Energy Technology Data Exchange (ETDEWEB)

    Hellman, Mats

    2007-04-15

    Corrosion in power plant equipment is to a large extent a result of poor lay-up procedures. This applies for all equipment on the water and steam side e.g. condensers, boilers, turbines, heat exchangers etc. In theory, lay-up procedures are quite straightforward. The main objective is to avoid a combination of water and oxygen on the steel surfaces within the system. When using dry lay-up procedure, a totally dry environment is essential. The corrosion of steel cannot take place if there is no humidity; in spite of the abundance of oxygen i.e. air. As an alternative the steam side system can be purged with nitrogen so that no air ingress can take place. When using wet lay-up procedures it is important to achieve an oxygen free environment. Creating a slight over-pressure thus avoiding air in leakage can achieve this. Oxygen scavengers might be used as an alternative. Usually problems of maintaining the above mentioned conditions are rarely of technical art. More likely it is due to a lack of knowledge and commitment or short sighted economical considerations. This report summarises the experiences gathered at several visits at plants and discussions with vendors, users and consultants in the power industry. In addition to that, guidelines from well-reputed organisations, international and domestic, have been studied. In many cases the power plant managers believe they have proper lay-up routines but often the routines just regard long time lay-up. This may be regarded as the most important case. However, a number of shorter plant outages in combination with poor lay-up routines can result in severe damages. There is a consensus that a proper lay-up can only be achieved by plant specific lay-up procedures. Each unit is unique in terms of needs and requirements. In order to have as low corrosion as possible a systematic review to evaluate and revise lay-up procedures is preferred. A high in-house knowledge of the power plant enhances the possibility to maintain the

  10. 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.

  11. Studies on Hot Corrosion of the 2.25 Cr-1Mo Boiler Tube Steel and Its Weldments in the Molten Salt Na2SO4-60 pct V2O5 Environment

    Science.gov (United States)

    Kumar, Ravindra; Tewari, V. K.; Prakash, S.

    2007-01-01

    Hot corrosion is mainly due to the dissolution of protective oxides in the molten salt at the metal surface and their reprecipitation at some other sites as nonprotective porous mass. The hot corrosion attack along the grain boundaries leading to subsurface precipitation of oxides and sulfides also contributes to weakening of material. Ferritic steel with 2.25Cr 1Mo is used widely as a candidate material in the steam generating system of power plants. Hot corrosion studies were conducted on 2.25Cr-1Mo unwelded as well as welded steel specimens with molten salt coated after exposure at 900 °C under cyclic conditions. The thermogravimetric technique was used to establish the kinetics of corrosion X-ray diffraction (XRD); scanning electron microscopy/energy-dispersive analysis (SEM/EDAX) was used to analyze the corrosion products.

  12. 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.

  13. Life assessment for vintage boilers

    Energy Technology Data Exchange (ETDEWEB)

    Auerkari, P.; Salonen, J.; Holmstroem, S. (VTT Technical Research Centre of Finland, Espoo (Finland)); Laaksonen, L.; Lehtinen, O. (Fortum, Naantali (Finland)); McNiven, U. (Fortum, Jyvaeskylae (Finland)); Maekinen, S.; Vaeaenaenen, V. (Helsingin Energia, Helsinki (Finland)); Nikkarila, R. (Inspecta, Espoo (Finland))

    2010-05-15

    The high temperature sections of power and combined heat and power (CHP) boilers are designed for some de facto expected but finite life. Several significant damage mechanisms must be taken into account, particularly in superheaters and reheaters that are designed for creep but also suffer from thermal degradation, external erosion and corrosion, and internal steam oxidation that will gradually increase the metal temperature. As rising temperature tends to accelerate all damage mechanisms, major effects can be expected from the internal oxide growth. The feedback loop is taken into account in procedures to predict superheater life from known tube dimensions, time in operation, and other initial data. The oxide effect can be mitigated by internal cleaning, but in-service spallation of a relatively thick internal oxide can also become significant in old plants. Spallation can create problems but extends the tube life by keeping the wall cooler than with an adherent oxide. Examples are shown for boilers with more than 150 000 h of service. (orig.)

  14. Selecting the right material for recovery boiler superheaters

    Energy Technology Data Exchange (ETDEWEB)

    Vakkilainen, E. K. (Lappeenranta Univ. of Technology (Finland)); Pohjanne, P. (VTT Technical Research Centre of Finland, Espoo (Finland))

    2010-05-15

    The aim of this paper is to examine the selection of superheater materials for recovery boilers. Fireside wastage in recovery boilers is mainly caused by formation of corrosive deposits, typically with aggressive molten alkali phases. Fireside corrosion can also be caused by gaseous components and is then usually associated with a reducing atmosphere. This active oxidation can affect superheater tubes even at temperatures lower than the first melting temperature. There is a wide array of available superheater materials to choose from and a few newer materials to be considered. The operating conditions and deposit properties must be looked at when material selection is done. The material choice has a significant effect to the cost of the recovery boiler, as the selection of the final superheater material can change the price by a factor of 10. (orig.)

  15. TA-2 Water Boiler Reactor Decommissioning Project

    Energy Technology Data Exchange (ETDEWEB)

    Durbin, M.E. (ed.); Montoya, G.M.

    1991-06-01

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

  16. High-solids black liquor firing in pulp and paper industry kraft recovery boilers: Phase 1 -- Final report. Volume 2: Project technical results

    Energy Technology Data Exchange (ETDEWEB)

    Southards, W.T.; Clement, J.L.; McIlroy, R.A.; Tharp, M.R.; Verrill, C.L.; Wessell, R.A.

    1995-11-01

    This project is a multiple-phase effort to develop technologies to improve high-solids black liquor firing in pulp mill recovery boilers. The principal means to this end is to construct and operate a pilot-scale recovery furnace simulator (RFS) in which these technologies can be tested. The Phase 1 objectives are to prepare a preliminary design for the RFS, delineate a project concept for evaluating candidate technologies, establish industrial partners, and report the results. Phase 1 addressed the objectives with seven tasks: Develop a preliminary design of the RFS; estimate the detailed design and construction costs of the RFS and the balance of the project; identify interested parties in the paper industry and key suppliers; plan the Phase 2 and Phase 3 tests to characterize the RFS; evaluate the economic justification for high-solids firing deployment in the industry; evaluate high-solids black liquor property data to support the RFS design; manage the project and reporting results, which included planning the future program direction.

  17. Experimental installation with pressurized fluidized bed boiler

    Energy Technology Data Exchange (ETDEWEB)

    Dobrzanski, W.; Szwarc, W.; Jurek, K.; Prokop, A. (Politechnika Warszawska (Poland). Instytut Techniki Cieplnej)

    1990-01-01

    Describes a test installation with a 3 MW pressurized fluidized bed boiler. The installation was commissioned at the Institute of Heat Engineering at the Technical University in Warsaw. Predesign assumptions and the lay-out of the installation are given. A schematic diagram of the pressurized (0.6 MPa) fluidized bed boiler with an inner diameter of 1.4 m and a total height of 5.45 m is shown. The fuel feeding system consists of a coal and adsorbent container, two feeders and an air jet pump for pneumatic transport. A water type boiler is integrated into the pressure vessel. Flue gas cyclones are also integrated into a separate pressure vessel. The computerized control system and instrumentation are described. Temperatures, pressures, pressure differences, rotational speeds and the chemical composition of gases are monitored.

  18. Chemical and mechanical control of corrosion product transport

    Energy Technology Data Exchange (ETDEWEB)

    Hede Larsen, O.; Blum, R. [I/S Fynsvaerket, Faelleskemikerne, Odense (Denmark); Daucik, K. [I/S Skaerbaekvaerket, Faelleskemikerne, Fredericia (Denmark)

    1996-12-01

    The corrosion products formed in the condensate and feedwater system of once-through boilers are precipitated and deposited inside the evaporator tubes mainly in the burner zone at the highest heat flux. Depositions lead to increased oxidation rate and increased metal temperature of the evaporator tubes, hereby decreasing tube lifetime. This effect is more important in the new high efficiency USC boilers due to increased feedwater temperature and hence higher thermal load on the evaporator tubes. The only way to reduce the load on the evaporator tubes is to minimise corrosion product transport to the boiler. Two general methods for minimising corrosion product transport to the boiler have been evaluated through measurement campaigns for Fe in the water/steam cycle in supercritical boilers within the ELSAM area. One method is to reduce corrosion in the low temperature condensate system by changing conditioning mode from alkaline volatile treatment (AVT) to oxygenated treatment (OT). The other method is to filtrate part of the condensate with a mechanical filter at the deaerator. The results show, that both methods are effective at minimising Fe-transport to the boiler, but changing to OT has the highest effect and should always be used, whenever high purity condensate is maintained. Whether mechanical filtration also is required, depends on the boiler, specifically the load on the evaporator. A simplified calculation model for lifetime evaluation of evaporator tubes has been developed. This model has been used for evaluating the effect of corrosion product transport to the boiler on evaporator tube lifetime. Conventional supercritical boilers generally can achieve sufficient lifetime by AVT and even better by OT, whereas all measures to reduce Fe-content of feedwater, including OT and mechanical filtration, should be taken, to ensure sufficient lifetime for the new boilers with advanced steam data - 290 bar/580 deg. C and above. (au)

  19. Organic Contaminants and Treatment Chemicals in Steam-Water Cycles: Thermal stability, decomposition products and flow-accelerated corrosion

    NARCIS (Netherlands)

    Moed, D.H.

    2015-01-01

    Boiler feedwater and steam have to be of high purity, because of the susceptibility of the steam-water cycle to corrosion. Organic contaminants break down in boilers by hydrothermolysis, leading to the formation of organic acid anions, which are suspected to cause corrosion of steam-water cycle comp

  20. Drying Milk With Boiler Exhaust

    Science.gov (United States)

    Broussard, M. R.

    1984-01-01

    Considerable energy saved in powdered-milk industry. Only special requirement boiler fired with natural gas or other clean fuel. Boiler flue gas fed to spray drier where it directly contacts product to be dried. Additional heat supplied by auxillary combustor when boiler output is low. Approach adaptable to existing plants with minimal investment because most already equipped with natural-gas-fired boilers.

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

    Energy Technology Data Exchange (ETDEWEB)

    Liss, William E; Cygan, David F

    2013-04-17

    Gas Technology Institute (GTI) and Cleaver-Brooks developed a new gas-fired steam generation system the Super Boiler for increased energy efficiency, reduced equipment size, and reduced emissions. The system consists of a firetube boiler with a unique staged furnace design, a two-stage burner system with engineered internal recirculation and inter-stage cooling integral to the boiler, unique convective pass design with extended internal surfaces for enhanced heat transfer, and a novel integrated heat recovery system to extract maximum energy from the flue gas. With these combined innovations, the Super Boiler technical goals were set at 94% HHV fuel efficiency, operation on natural gas with <5 ppmv NOx (referenced to 3%O2), and 50% smaller than conventional boilers of similar steam output. To demonstrate these technical goals, the project culminated in the industrial demonstration of this new high-efficiency technology on a 300 HP boiler at Clement Pappas, a juice bottler located in Ontario, California. The Super Boiler combustion system is based on two stage combustion which combines air staging, internal flue gas recirculation, inter-stage cooling, and unique fuel-air mixing technology to achieve low emissions rather than external flue gas recirculation which is most commonly used today. The two-stage combustion provides lower emissions because of the integrated design of the boiler and combustion system which permit precise control of peak flame temperatures in both primary and secondary stages of combustion. To reduce equipment size, the Super Boiler's dual furnace design increases radiant heat transfer to the furnace walls, allowing shorter overall furnace length, and also employs convective tubes with extended surfaces that increase heat transfer by up to 18-fold compared to conventional bare tubes. In this way, a two-pass boiler can achieve the same efficiency as a traditional three or four-pass firetube boiler design. The Super Boiler is consequently

  2. Screening and Quantification of Aliphatic Primary Alkyl Corrosion Inhibitor Amines in Water Samples by Paper Spray Mass Spectrometry.

    Science.gov (United States)

    Jjunju, Fred P M; Maher, Simon; Damon, Deidre E; Barrett, Richard M; Syed, S U; Heeren, Ron M A; Taylor, Stephen; Badu-Tawiah, Abraham K

    2016-01-19

    Direct analysis and identification of long chain aliphatic primary diamine Duomeen O (n-oleyl-1,3-diaminopropane), corrosion inhibitor in raw water samples taken from a large medium pressure water tube boiler plant water samples at low LODs (corrosion inhibitors in an industrial water boiler plant and other related samples in the water treatment industry. This approach was applied for the analysis of three complex water samples including feedwater, condensate water, and boiler water, all collected from large medium pressure (MP) water tube boiler plants, known to be dosed with varying amounts of polyamine and amine corrosion inhibitor components. Polyamine chemistry is widely used for example in large high pressure (HP) boilers operating in municipal waste and recycling facilities to prevent corrosion of metals. The samples used in this study are from such a facility in Coventry waste treatment facility, U.K., which has 3 × 40 tonne/hour boilers operating at 17.5 bar.

  3. The role of abrasion and corrosion in grinding media wear: Annual technical progress report. [Taconite; molybdenite; quartzite

    Energy Technology Data Exchange (ETDEWEB)

    Moore, J.J.; Iwasaki, I.

    1984-06-12

    Aim of this research program is to establish the effect of mill size and batch or continuous operation on the role of corrosive and abrasive wear during mineral grinding operations. Grinding ball wear tests are being conducted on the laboratory, pilot plant and industrial scale. This report gives the results of the first year's work of the two year research program and are discussed under the following headings: Wear Tests in an 8-inch Laboratory Mill (Using Three Different Ball Chemistries for Both Taconite and Molybdenite Ore); Wear Tests in a 36-inch Batch Mill (Using High Carbon Low Alloy Steel Balls with Taconite); Mechanisms of Erosive Wear in Taconite Grinding (Using Mild Steel Balls); The Effect of Slurry Rheology on Grinding Media Wear (Using Mild Steel Balls - Quartzite Combination); and Pilot Plant continuous Grinding Tests (Using High Carbon Low Alloy Steel Balls with Taconite Ore).

  4. Accelerated cyclic corrosion tests

    OpenAIRE

    Prošek T.

    2016-01-01

    Accelerated corrosion testing is indispensable for material selection, quality control and both initial and residual life time prediction for bare and painted metallic, polymeric, adhesive and other materials in atmospheric exposure conditions. The best known Neutral Salt Spray (NSS) test provides unrealistic conditions and poor correlation to exposures in atmosphere. Modern cyclic accelerated corrosion tests include intermittent salt spray, wet and dry phases and eventually other technical p...

  5. Methods of Nitrogen Oxide Reduction in Pellet Boilers

    OpenAIRE

    Žandeckis, A; Blumberga, D; Rochas, C.; Veidenbergs, I; Siliņš, K

    2010-01-01

    The main goal of this research was to create and test technical solutions that reduce nitrogen oxide emissions in low-capacity pellet boiler. During the research, wood pellets were incinerated in a pellet boiler produced in Latvia with a rated capacity of 15 kW. During the research two NOx emission reduction methods were tested: secondary air supply in the chamber and recirculation of flue gases. Results indicated a drop of NOx concentration only for flue gas recirculation methods. Maximum re...

  6. 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,...

  7. Steam boiler technology

    Energy Technology Data Exchange (ETDEWEB)

    Teir, S.

    2003-07-01

    This book is the published version of the e-book with the same name. The interactive lecture slides, which accompany most chapters, exist only in the online version and on the attached CD-Rom. The Steam Boiler Technology e-book is the main course book for the course on steam boiler technology provided by the Laboratory of Energy Engineering and Environmental Protection at Helsinki University of Technology. The steam boiler technology e-Book is provided by the Laboratory of Energy Engineering and Environmental Protection at Helsinki University of Technology. The book covers the basics and the history of steam generation, modern boilers types and applications, steam/water circulation design, feedwater and steam systems components, heat exchangers in steam boilers, boiler calculations, thermal design of heat exchangers. The chapters of the second edition have been corrected based on reader and reviewer comments, and four new chapters have been added. The user interface of the electronic version has also been updated. The password for the online book will be changed once a year. If you have problems accessing the online book, or need a new password, please contact sebastian.teir@hut.fi.

  8. Corrosion '98: 53. annual conference and exposition, proceedings

    International Nuclear Information System (INIS)

    Vehicle Corrosion Resistance; Seawater Injection Systems; Automating Improved Materials Performance; Boiler Water Corrosion; and New Advances in Pipeline Rehabilitation Coatings and Associated Technology. Separate abstracts were prepared for some of the papers

  9. Greener Approach towards Corrosion Inhibition

    OpenAIRE

    Neha Patni; Shruti Agarwal; Pallav Shah

    2013-01-01

    Corrosion control of metals is technically, economically, environmentally, and aesthetically important. The best option is to use inhibitors for protecting metals and alloys against corrosion. As organic corrosion inhibitors are toxic in nature, so green inhibitors which are biodegradable, without any heavy metals and other toxic compounds, are promoted. Also plant products are inexpensive, renewable, and readily available. Tannins, organic amino acids, alkaloids, and organic dyes of plant or...

  10. Evaluation of corrosion attack of chimney liners

    Directory of Open Access Journals (Sweden)

    Blahetová M.

    2016-06-01

    Full Text Available The case study of chimney liner corrosion addresses three specific cases of damage of chimney systems from of stainless steels. These systems were used for flue of gas arising from the combustion of brown coal in small automatic boilers, which are used for heating. Detailed analyzes implied that the cause of devastating corrosion of the steel AISI 316 and 304 steel (CSN 17349, 17241 was particularly high content of halides (chlorides and fluorides, which caused a severe pitting corrosion, which led up to the perforation of the liner material. Simultaneous reduction of the thickness of the used sheets was due to by the general corrosion, which was caused by the sulfur in the solid fuel. The condensation then led to acid environment and therefore the corrosion below the dew point of the sulfuric acid has occurred. All is documented by metallographic analysis and microanalysis of the corrosion products.

  11. Innovative Clean Coal Technology (ICCT): 500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Technical progress report: First quarter 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    This quarterly report discusses the technical progress of an Innovative Clean Coal Technology (ICCT) demonstration being conducted at Georgia Power Company`s Plant Hammond Unit 4 located near Rome, Georgia. The primary goal of this project is the characterization of the low NO{sub x} combustion equipment through the collection and analysis of long-term emissions data. A target of achieving fifty percent NO{sub x} reduction using combustion modifications has been established for the project. The project provides a stepwise retrofit of an advanced overfire air (AOFA) system followed by low NO{sub x} burners (LNB). During each test phase of the project, diagnostic, performance, long-term, and verification testing will be performed. These tests are used to quantify the NO{sub x} reductions of each technology and evaluate the effects of those reductions on other combustion parameters such as particulate characteristics and boiler efficiency. During this quarter, long-term testing of the LNB + AOFA configuration continued and no parametric testing was performed. Further full-load optimization of the LNB + AOFA system began on March 30, 1993. Following completion of this optimization, comprehensive testing in this configuration will be performed including diagnostic, performance, verification, long-term, and chemical emissions testing. These tests are scheduled to start in May 1993 and continue through August 1993. Preliminary engineering and procurement are progressing on the Advanced Low NOx Digital Controls scope addition to the wall-fired project. The primary activities during this quarter include (1) refinement of the input/output lists, (2) procurement of the distributed digital control system, (3) configuration training, and (4) revision of schedule to accommodate project approval cycle and change in unit outage dates.

  12. The Corrosion and Corrosion Fatigue Behavior of Nickel Based Alloy Weld Overlay and Coextruded Claddings

    Science.gov (United States)

    Stockdale, Andrew

    The use of low NOx boilers in coal fired power plants has resulted in sulfidizing corrosive conditions within the boilers and a reduction in the service lifetime of the waterwall tubes. As a solution to this problem, Ni-based weld overlays are used to provide the necessary corrosion resistance however; they are susceptible to corrosion fatigue. There are several metallurgical factors which give rise to corrosion fatigue that are associated with the localized melting and solidification of the weld overlay process. Coextruded coatings offer the potential for improved corrosion fatigue resistance since coextrusion is a solid state coating process. The corrosion and corrosion fatigue behavior of alloy 622 weld overlays and coextruded claddings was investigated using a Gleeble thermo-mechanical simulator retrofitted with a retort. The experiments were conducted at a constant temperature of 600°C using a simulated combustion gas of N2-10%CO-5%CO2-0.12%H 2S. An alternating stress profile was used with a minimum tensile stress of 0 MPa and a maximum tensile stress of 300 MPa (ten minute fatigue cycles). The results have demonstrated that the Gleeble can be used to successfully simulate the known corrosion fatigue cracking mechanism of Ni-based weld overlays in service. Multilayer corrosion scales developed on each of the claddings that consisted of inner and outer corrosion layers. The scales formed by the outward diffusion of cations and the inward diffusion of sulfur and oxygen anions. The corrosion fatigue behavior was influenced by the surface finish and the crack interactions. The initiation of a large number of corrosion fatigue cracks was not necessarily detrimental to the corrosion fatigue resistance. Finally, the as-received coextruded cladding exhibited the best corrosion fatigue resistance.

  13. Ash deposition and high temperature corrosion at combustion of aggressive fuels

    Energy Technology Data Exchange (ETDEWEB)

    Hede Larsen, O. [I/S Fynsvaerket, Faelleskemikerne, Odense (Denmark); Henriksen, N. [Elsamprojekt A/S, Faelleskemikerne, Fredericia (Denmark)

    1996-12-01

    In order to reduce CO{sub 2} emission, ELSAM is investigating the possibilities of using biomass - mainly straw - for combustion in high efficiency power plants. As straw has very high contents of chlorine and potassium, a fuel with high corrosion and ash deposition propensities has been introduced. ELSAM has investigated 3 ultra supercritical boiler concepts for combustion of straw alone or together with coal: (1) PF boilers with a relatively low share of straw, (2) CFB boilers with low to high share of straw and (3) vibrating grate boilers with 100% straw. These investigations has mainly been full-scale tests with straw fed into existing boilers. Corrosion tests have been performed in these boilers using temperature regulated probes and in-plant test tubes in existing superheaters. The corrosion has been determined by detailed measurements of wall thickness reduction and light optical microscopic measurements of the material degradation due to high temperature corrosion. Corrosion mechanisms have been evaluated using SEM/EDX together with thermodynamical considerations based on measurements of the chemical environment in the flue gas. Ash deposition is problematic in CFB boilers and in straw fired boilers, especially in years with high potassium and chlorine content of the straw. This ash deposition also is related to condensation of KCl and can probably only be handled by improved cleaning devices. (EG)

  14. Installations of SNCR on bark-fired boilers

    International Nuclear Information System (INIS)

    Experience has been collected from the twelve bark-fired boilers in Sweden with selective non catalytic reduction (SNCR) installations to reduce emissions of nitrogen oxides. Most of the boilers have slope grates, but there are also two boilers with cyclone ovens and two fluidized bed boilers. In addition to oil there are also possibilities to burn other fuel types in most boilers, such as sludge from different parts of the pulp and paper mills, saw dust and wood chips. The SNCR installations seems in general to be of simple design. In most installations the injection nozzles are located in existing holes in the boiler walls. The availability is reported to be good from several of the SNCR installations. There has been tube leakage in several boilers. The urea system has resulted in corrosion and in clogging of one oil burner. This incident has resulted in a decision not to use SNCR system with the present design of the system. The fuel has also caused operational problems with the SNCR system in several of the installations due to variations in the moisture content and often high moisture content in bark and sludge, causing temperature variations. The availability is presented to be high for the SNCR system at several of the plants, in two of them about 90 %. The results in NOx reduction vary between the installations depending on boiler, fuel and operation. The emissions are between 45 and 100 mg NO2/MJ fuel input and the NOx reduction rates are in most installations between 30 and 40 %, the lowest 20 and the highest 70 %. 13 figs, 3 tabs

  15. Corrosion products in power generating systems

    International Nuclear Information System (INIS)

    The important mechanisms of corrosion and corrosion product movement and fouling in the heat transport systems of thermal electric generating stations are reviewed. Oil- and coal-fired boilers are considered, along with nuclear power systems - both direct and indirect cycle. Thus, the fireside and waterside in conventional plants, and the primary coolant and steam-raising circuits in water-cooled reactors, are discussed. Corrosion products in organic- and liquid-metal-cooled reactors also are shown to cause problems if not controlled, while their beneficial effects on the cooling water side of condensers are described. (auth)

  16. Solid-phase extraction-gas chromatography and solid-phase extraction-gas chromatography-mass spectrometry determination of corrosion inhibiting long-chain primary alkyl amines in chemical treatment of boiler water in water-steam systems of power plants.

    Science.gov (United States)

    Kusch, Peter; Knupp, Gerd; Hergarten, Marcus; Kozupa, Marian; Majchrzak, Maria

    2006-04-28

    Gas chromatography with simultaneous flame-ionization detection (FID) and a nitrogen-phosphorus detection (NPD) as well as gas chromatography-mass spectrometry (GC/MS) has been used to characterize long-chain primary alkyl amines after derivatization with trifluoroacetic anhydride (TFAA). Electron impact ionization- (EI) and negative chemical ionization (NCI) mass spectra of trifluoroacetylated derivatives of the identified tert-octadecylamines are presented for the first time. The corrosion inhibiting alkyl amines were applied in a water-steam circuit of energy systems in the power industry. Solid-phase extraction (SPE) with octadecyl bonded silica (C18) sorbents followed by gas chromatography were used for quantification of the investigated tert-octadecylamines in boiler water, superheated steam and condensate samples from the power plant. The estimated values were: 89 microg l(-1)(n = 5, RSD = 7.8%), 45 microg l(-1) (n = 5, RSD = 5.4%) and 37 microg l(-1)(n = 5, RSD = 2.3%), respectively. PMID:16483586

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

    International Nuclear Information System (INIS)

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

  18. Steam generator corrosion 2007; Dampferzeugerkorrosion 2007

    Energy Technology Data Exchange (ETDEWEB)

    Born, M. (ed.)

    2007-07-01

    Between 8th and 9th November, 2007, SAXONIA Standortentwicklungs- und -verwertungsgesellschaft GmbH (Freiberg, Federal Republic of Germany) performed the 3rd Freiberger discussion conference ''Fireside boiler corrosion''. The topics of the lectures are: (a) Steam generator corrosion - an infinite history (Franz W. Alvert); (b) CFD computations for thermal waste treatment plants - a contribution for the damage recognition and remedy (Klaus Goerner, Thomas Klasen); (c) Experiences with the use of corrosion probes (Siegfried R. Horn, Ferdinand Haider, Barbara Waldmann, Ragnar Warnecke); (d) Use of additives for the limitation of the high temperature chlorine corrosion as an option apart from other measures to the corrosion protection (Wolfgang Spiegel); (e) Current research results and aims of research with respect to chlorine corrosion (Ragnar Warnecke); (f) Systematics of the corrosion phenomena - notes for the enterprise and corrosion protection (Thomas Herzog, Wolfgang Spiegel, Werner Schmidl); (g) Corrosion protection by cladding in steam generators of waste incinerators (Joerg Metschke); (h) Corrosion protection and wear protection by means of thermal spraying in steam generators (Dietmar Bendix); (i) Review of thick film nickelized components as an effective protection against high-temperature corrosion (Johann-Wilhelm Ansey); (j) Fireproof materials for waste incinerators - characteristics and profile of requirement (Johannes Imle); (k) Service life-relevant aspects of fireproof linings in the thermal recycling of waste (Till Osthoevener and Wolfgang Kollenberg); (l) Alternatives to the fireproof material in the heating space (Heino Sinn); (m) Cladding: Inconal 625 contra 686 - Fundamentals / applications in boiler construction and plant construction (Wolfgang Hoffmeister); (n) Thin films as efficient corrosion barriers - thermal spray coating in waste incinerators and biomass firing (Ruediger W. Schuelein, Steffen Hoehne, Friedrich

  19. MODELLING, SIMULATING AND OPTIMIZING BOILERS

    DEFF Research Database (Denmark)

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

    2004-01-01

    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...... shape to the actual application. In the paper an optimization example is shown and the results discussed. By means of the developed model it is shown how the optimum changes from a boiler favoring a good dynamic capability (i.e. a boiler with a relatively large volume) to a boiler not penalizing...

  20. Towards Long-Term Corrosion Resistance in FE Service Environments

    Energy Technology Data Exchange (ETDEWEB)

    G. R. Holcomb and P. Wang

    2010-10-01

    The push for carbon capture and sequestration for fossil fuel energy production has materials performance challenges in terms of high temperature oxidation and corrosion resistance. Such challenges will be illustrated with examples from several current technologies that are close to being realized. These include cases where existing technologies are being modified—for example fireside corrosion resulting from increased corrosivity of flue gas in coal boilers refit for oxy-fuel combustion, or steam corrosion resulting from increased temperatures in advanced ultra supercritical steam boilers. New technology concepts also push the high temperature corrosion and oxidation limits—for example the effects of multiple oxidants during the use of high CO2 and water flue gas used as turbine working fluids.

  1. 等离子喷涂工艺对锅炉管束用Fe基非晶涂层组织结构和耐蚀性能的影响%Effect of Spray Process on the Microstructure and Corrosion-resistance of Fe-based Amorphous Coatings Obtained by Plasma Spray on the Boiler Tubes

    Institute of Scientific and Technical Information of China (English)

    高振; 郝建民; 韩建军; 鲁元; 陈永楠; 李世波

    2015-01-01

    ABSTRACT:Objective To investigate the effects of plasma spray power and time on the phase, microstructure and corrosion-re-sistance of the amorphous coating on the boiler tubes. Methods XRD, SEM and electrochemical polarization research were adopt-ed. Results The coating with high fraction of amorphous phase was obtained, which had a flat and compact surface. The amorphous fraction and porosity decreased and the density increased with the increasing spray power and time. The coatings exhibited an excel-lent ability to resist corrosion with wide passive region in 0. 5 mol/L H2 SO4 and 3. 5% NaCl solutions. And the coatings exhibited wider passive region and lower corrosion current density in 0. 5 mol/L H2 SO4 and 3. 5% NaCl solutions, respectively. With in-crease of the spray power and time, the anodic polarization curves of the amorphous coatings were passivated with wider passive re-gion and lower passive current density. Conclusion The path and flow resistance that corrosive liquid permeated the substrate were increased, and the corrosion resistance of the coating was improved, owing to the decreased porosity and increased coating thick-ness with the increasing spray power and time.%目的:研究等离子喷涂功率和喷涂时间对锅炉管束用Fe基非晶涂层的相组成、微观组织结构及涂层耐蚀性能的影响。方法通过X射线衍射、扫描电子显微镜和三电极电化学研究进行分析。结果涂层主要由非晶相组成,表面较为平整致密;随着喷涂功率和喷涂时间的增加,涂层非晶相含量降低,孔隙率降低,致密性升高。非晶涂层在0.5 mol/L H2SO4溶液和在3.5%(质量分数)NaCl溶液中均表现出良好的钝化作用,在0.5 mol/L H2 SO4溶液中钝化区较宽,在3.5%NaCl溶液中自腐蚀电流密度较低。随喷涂功率和时间的增加,阳极极化曲线钝化区加宽,电流密度降低。结论喷涂功率升高会导致涂层孔隙率下降

  2. Review of state-of-the-art of solar collector corrosion processes. Task 1 of solar collector studies for solar heating and cooling applications. Final technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    Clifford, J E; Diegle, R B

    1980-04-11

    The state-of-the-art of solar collector corrosion processes is reviewed, and Task 1 of a current research program on use of aqueous heat transfer fluids for solar heating and cooling is summarized. The review of available published literature has indicated that lack of quantitative information exists relative to collector corrosion at the present time, particularly for the higher temperature applications of solar heating and cooling compared to domestic water heating. Solar collector systems are reviewed from the corrosion/service life viewpoint, with emphasis on various applications, collector design, heat transfer fluids, and freeze protection methods. Available information (mostly qualitative) on collector corrosion technology is reviewed to indicate potential corrosion problem areas and corrosion prevention practices. Sources of limited quantitative data that are reviewed are current solar applications, research programs on collector corrosion, and pertinent experience in related applications of automotive cooling and non-solar heating and cooling. A data bank was developed to catalog corrosion information. Appendix A of this report is a bibliography of the data bank, with abstracts reproduced from presently available literature accessions (about 220). This report is presented as a descriptive summary of information that is contained in the data bank.

  3. High temperature corrosion of metals

    International Nuclear Information System (INIS)

    This paper covers three main topics: 1. high temperature oxidation of metals and alloys, 2. corrosion in sulfur containing environments and 3. structural changes caused by corrosion. The following 21 subjects are discussed: Influence of implanted yttrium and lanthanum on the oxidation behaviour of beta-NiA1; influence of reactive elements on the adherence and protective properties of alumina scales; problems related to the application of very fine markers in studying the mechanism of thin scale formation; oxidation behaviour of chromia forming Co-Cr-Al alloys with or without reactive element additions; growth and properties of chromia-scales on high-temperature alloys; quantification of the depletion zone in high temperature alloys after oxidation in process gas; effects of HC1 and of N2 in the oxidation of Fe-20Cr; investigation under nuclear safety aspects of Zircaloy-4 oxidation kinetics at high temperatures in air; on the sulfide corrosion of metallic materials; high temperature sulfide corrosion of Mn, Nb and Nb-Si alloys; corrosion behaviour or NiCrAl-based alloys in air and air-SO2 gas mixtures; sulfidation of cobalt at high temperatures; preoxidation for sulfidation protection; fireside corrosion and application of additives in electric utility boilers; transport properties of scales with complex defect structures; observations of whiskers and pyramids during high temperature corrosion of iron in SO2; corrosion and creep of alloy 800H under simulated coal gasification conditions; microstructural changes of HK 40 cast alloy caused by exploitation in tubes in steam reformer installation; microstructural changes during exposure in corrosive environments and their effect on mechanical properties; coatings against carburization; mathematical modeling of carbon diffusion and carbide precipitation in Ni-Cr-based alloys. (MM)

  4. 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.

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

    OpenAIRE

    * Gokulakannan A, Karuppasamy K

    2016-01-01

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

  6. Pipeline Corrosion Prevention Technical Research and Application in Shengli Oilifeld%胜利油田管道防腐技术研究及应用

    Institute of Scientific and Technical Information of China (English)

    闫方平

    2014-01-01

    In allusion to corrosion of pipeline in Shengli Oilfield,electrochemical testing method is used to study and analyze the influence law of factors in pressure ,temperature ,velocity of flow and pH value to corrosion. Electrochemical method and coupon weight methods are utilized to assess corrosion inhibitors A,B, C and D. It is indicated that corrosion inhibitors A has a best effect. Corrosion control tests with corrosion inhibitors A,Test results show that corrosion is effectively inhibited in the pipeline and economic benefit is improved afterward.%采用电化学试验方法,研究了压力、温度、流速和pH值等因素对腐蚀的影响规律。针对胜利油田管道腐蚀问题,采用电化学法和挂片法对A、B、C和D四种防腐剂进行了评价,结果表明,防腐剂A的防腐效果较好,选用防腐剂A进行现场试验,结果表明,加入防腐剂后有效抑制了腐蚀,有利于提高油田经济效益。

  7. An update on corrosion monitoring in cylinder storage yards

    Energy Technology Data Exchange (ETDEWEB)

    Henson, H.M.; Newman, V.S.; Frazier, J.L. [Oak Ridge K-25 Site, TN (United States)

    1991-12-31

    Depleted uranium, from US uranium isotope enrichment activities, is stored in the form of solid uranium hexafluoride (UF{sub 6}) in A285 and A516 steel cylinders designed and manufactured to ASME Boiler and Pressure Vessel Code criteria. In general, storage facilities are open areas adjacent to the enrichment plants where the cylinders are exposed to weather. This paper describes the Oak Ridge program to determine the general corrosion behavior of UF{sub 6} cylinders, to determine cylinder yard conditions which are likely to affect long term storage of this material, and to assess cylinder storage yards against these criteria. This program is targeted at conditions specific to the Oak Ridge cylinder yards. Based on (a) determination of the current cylinder yard conditions, (b) determination of rusting behavior in regions of the cylinders showing accelerated attack, (c) monitoring of corrosion rates through periodic measurement of test coupons placed within the cylinder yards, and (d) establishment of a computer base to incorporate and retain these data, the technical division is working with the enrichment sites to implement an upgraded system for storage of this material until such time as it is used or converted.

  8. 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.

  9. Super Boiler 2nd Generation Technology for Watertube Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Mr. David Cygan; Dr. Joseph Rabovitser

    2012-03-31

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

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

    Directory of Open Access Journals (Sweden)

    Gaponenko A. M.

    2014-12-01

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

  11. 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

  12. Small boiler uses waste coal

    Energy Technology Data Exchange (ETDEWEB)

    Virr, M.J. [Spinheat Ltd. (United States)

    2009-07-15

    Burning coal waste in small boilers at low emissions poses considerable problem. While larger boiler suppliers have successfully installed designs in the 40 to 80 MW range for some years, the author has been developing small automated fluid bed boiler plants for 25 years that can be applied in the range of 10,000 to 140,000 lbs/hr of steam. Development has centered on the use of an internally circulating fluid bed (CFB) boiler, which will burn waste fuels of most types. The boiler is based on the traditional D-shaped watertable boiler, with a new type of combustion chamber that enables a three-to-one turndown to be achieved. The boilers have all the advantages of low emissions of the large fluid boilers while offering a much lower height incorporated into the package boiler concept. Recent tests with a waste coal that had a high nitrogen content of 1.45% demonstrated a NOx emission below the federal limit of 0.6 lbs/mm Btu. Thus a NOx reduction on the order of 85% can be demonstrate by combustion modification alone. Further reductions can be made by using a selective non-catalytic reduction (SNCR) system and sulfur absorption of up to 90% retention is possible. The article describes the operation of a 30,000 lbs/hr boiler at the Fayette Thermal LLC plant. Spinheat has installed three ICFB boilers at a nursing home and a prison, which has been tested on poor-grade anthracite and bituminous coal. 2 figs.

  13. Fatigue and Corrosion in Metals

    CERN Document Server

    Milella, Pietro Paolo

    2013-01-01

    This textbook, suitable for students, researchers and engineers, gathers the experience of more than 20 years of teaching fracture mechanics, fatigue and corrosion to professional engineers and running experimental tests and verifications to solve practical problems in engineering applications. As such, it is a comprehensive blend of fundamental knowledge and technical tools to address the issues of fatigue and corrosion. The book initiates with a systematic description of fatigue from a phenomenological point of view, since the early signs of submicroscopic damage in few surface grains and continues describing, step by step, how these precursors develop to become mechanically small cracks and, eventually, macrocracks whose growth is governed by fracture mechanics. But fracture mechanics is also introduced to analyze stress corrosion and corrosion assisted fatigue in a rather advanced fashion. The author dedicates a particular attention to corrosion starting with an electrochemical treatment that mechanical e...

  14. 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.

  15. 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.

  16. Nanocomposite films for corrosion protection

    OpenAIRE

    Sababi, Majid

    2013-01-01

    This thesis describes technical and scientific aspects of new types of composite films/coatings for corrosion protection of carbon steel, composite films with nanometer thickness consisting of mussel adhesive protein (Mefp‐1) and ceria nanoparticles, and polymeric composite coatings with micrometre thickness consisting of conducting polymer and ceria nanoparticles in a UV‐curing polyester acrylate (PEA) resin. The influence of microstructure on corrosion behaviour was studied for a Fe‐Cr‐V‐N ...

  17. Corrosion protection

    International Nuclear Information System (INIS)

    This invention describes a corrosion protection device for long-term storage containers of radioactive matter, in particular of irradiated fuel elements stored in geological formations apt for the purpose. This device prevents corrosion of the containers even if water emerges unexpectedly, or, in any case, inhibits and minimizes corrosion. The device comprehends reactive anodes that are connected to the containers by means of conductive connections. (orig.)

  18. Corrosion protection

    Science.gov (United States)

    Brown, Donald W.; Wagh, Arun S.

    2003-05-27

    There has been invented a chemically bonded phosphate corrosion protection material and process for application of the corrosion protection material for corrosion prevention. A slurry of iron oxide and phosphoric acid is used to contact a warm surface of iron, steel or other metal to be treated. In the presence of ferrous ions from the iron, steel or other metal, the slurry reacts to form iron phosphates which form grains chemically bonded onto the surface of the steel.

  19. 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

  20. COMBINED BOILER WITH TPV

    OpenAIRE

    Björk, Magnus

    2013-01-01

    A TPV-system consists of a hot surface emitting heat radiation on a solar cell with a narrow bandgap.  A unit consisting of a boiler and a TPV-system has been constructed for testing of the performance of TPV cells. The emitter is heated by a fuel consisting of RME-oil. The radiation is collected and concentrated through two reflecting cones formed like a Faberge-egg, with an edge-type optical filter between the cones. The Faberge-egg is treated with electro-polishing in order to obtain a hig...

  1. Modelling, simulating and optimizing Boilers

    DEFF Research Database (Denmark)

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

    2003-01-01

    This paper describes the modelling, simulating and optimizing including experimental verication 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 re tube boilers. A detailed dynamic mod...

  2. Organic Contaminants and Treatment Chemicals in Steam-Water Cycles: Thermal stability, decomposition products and flow-accelerated corrosion

    OpenAIRE

    D. H. Moed

    2015-01-01

    Boiler feedwater and steam have to be of high purity, because of the susceptibility of the steam-water cycle to corrosion. Organic contaminants break down in boilers by hydrothermolysis, leading to the formation of organic acid anions, which are suspected to cause corrosion of steam-water cycle components. The impact and behavior of organic decomposition products in the steam-water cycle are not well understood. While guidelines for organic contaminants are becoming stricter, organic treatmen...

  3. The Development and Research on the Coordinate Control Strategy Between Turbine and Boiler in Fossil Power Plant

    Institute of Scientific and Technical Information of China (English)

    WEI Shuangying

    2006-01-01

    Based on the research on domestic and international automatic technical development in fossil power plant, the paper analyses the recent situation of the coordinate control system between turbine and boiler of domestic fossil Power Plant, provides the development thought of coordinate control system between turbine and boiler, and describes the application prospect in control system of fossil power plant combining with the application experience.

  4. 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.

  5. NASA's Corrosion Technology Laboratory at the Kennedy Space Center: Anticipating, Managing, and Preventing Corrosion

    Science.gov (United States)

    Calle, Luz Marina

    2015-01-01

    The marine environment at NASAs Kennedy Space Center (KSC) has been documented by ASM International (formerly American Society for Metals) as the most corrosive in North America. With the introduction of the Space Shuttle in 1981, the already highly corrosive conditions at the launch pads were rendered even more severe by the highly corrosive hydrochloric acid (HCl) generated by the solid rocket boosters (SRBs). Numerous failures at the launch pads are caused by corrosion. The structural integrity of ground infrastructure and flight hardware is critical to the success, safety, cost, and sustainability of space missions. NASA has over fifty years of experience dealing with unexpected failures caused by corrosion and has developed expertise in corrosion control in the launch and other environments. The Corrosion Technology Laboratory at KSC evolved, from what started as an atmospheric exposure test site near NASAs launch pads, into a capability that provides technical innovations and engineering services in all areas of corrosion for NASA, external partners, and customers.This paper provides a chronological overview of NASAs role in anticipating, managing, and preventing corrosion in highly corrosive environments. One important challenge in managing and preventing corrosion involves the detrimental impact on humans and the environment of what have been very effective corrosion control strategies. This challenge has motivated the development of new corrosion control technologies that are more effective and environmentally friendly. Strategies for improved corrosion protection and durability can have a huge impact on the economic sustainability of human spaceflight operations.

  6. Summary of workshop on materials issues associated with low-NO{sub x} combustion conditions in fossil-fired boilers

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    It was anticipated by some members of the high-temperature corrosion community that the fitting of low-NO{sub x} burners to coal-fired power plants would lead to an increase in furnace wall corrosion, as a result of the relatively substoichiometric conditions created by the staged combustion process. These expectations were not borne out by initial experience. Recently, however, cases of severe furnace wall corrosion have been reported by some U.S. utility boilers retrofitted with modern low-NO{sub x} burners. There is extensive experience of furnace wall corrosion in utility boilers in the U.K., which indicates that excessive fireside corrosion rates (>200 nm/hr; 34 mil/yr) are experienced when tubes are exposed simultaneously to substoichiometric gaseous environments (CO>3.0 percent) and high radiant heat fluxes. Such conditions may be generated when flame impingement occurs. Where such conditions persist, increases in fuel chlorine content will exacerbate the rate of metal loss. In the absence of either circumstances, corrosion rates are much reduced and little influence of coal chlorine content is anticipated. Although the corrosion is essentially sulfidation caused by H{sub 2}S in the flue gas, the contribution of fuel sulfur in the corrosion experience by U.K. boilers is unresolved, partly because of the relatively small range in sulfur content of coals burned in U.K. utility boilers. The intent of this workshop was three-fold: to better define the problem in terms of the form and rate of attack; to examine what is known about its root causes; and to review the potential for using corrosion-resistant materials as part of the solution.

  7. 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.

  8. Failure analyses and weld repair of boiler feed water pumps

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-12-31

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

  9. DPC materials and corrosion environments.

    Energy Technology Data Exchange (ETDEWEB)

    Ilgen, Anastasia Gennadyevna; Bryan, Charles R.; Teich-McGoldrick, Stephanie; Hardin, Ernest

    2014-10-01

    After an exposition of the materials used in DPCs and the factors controlling material corrosion in disposal environments, a survey is given of the corrosion rates, mechanisms, and products for commonly used stainless steels. Research needs are then identified for predicting stability of DPC materials in disposal environments. Stainless steel corrosion rates may be low enough to sustain DPC basket structural integrity for performance periods of as long as 10,000 years, especially in reducing conditions. Uncertainties include basket component design, disposal environment conditions, and the in-package chemical environment including any localized effects from radiolysis. Prospective disposal overpack materials exist for most disposal environments, including both corrosion allowance and corrosion resistant materials. Whereas the behavior of corrosion allowance materials is understood for a wide range of corrosion environments, demonstrating corrosion resistance could be more technically challenging and require environment-specific testing. A preliminary screening of the existing inventory of DPCs and other types of canisters is described, according to the type of closure, whether they can be readily transported, and what types of materials are used in basket construction.

  10. National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers; Guidance for Calculating Emission Credits Resulting from Implementation of Energy Conservation Measures

    Energy Technology Data Exchange (ETDEWEB)

    Cox, Daryl [ORNL; Papar, Riyaz [Hudson Technologies; Wright, Dr. Anthony [ALW Consulting

    2012-07-01

    The purpose of this document is to provide guidance for developing a consistent approach to documenting efficiency credits generated from energy conservation measures in the Implementation Plan for boilers covered by the Boiler MACT rule (i.e., subpart DDDDD of CFR part 63). This document divides Boiler System conservation opportunities into four functional areas: 1) the boiler itself, 2) the condensate recovery system, 3) the distribution system, and 4) the end uses of the steam. This document provides technical information for documenting emissions credits proposed in the Implementation Plan for functional areas 2) though 4). This document does not include efficiency improvements related to the Boiler tune-ups.

  11. National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial, Commercial, and Institutional Boilers; Guidance for Calculating Efficiency Credits Resulting from Implementation of Energy Conservation Measures

    Energy Technology Data Exchange (ETDEWEB)

    Cox, Daryl [ORNL; Papar, Riyaz [Hudson Technologies; Wright, Dr. Anthony [ALW Consulting

    2013-02-01

    The purpose of this document is to provide guidance for developing a consistent approach to documenting efficiency credits generated from energy conservation measures in the Implementation Plan for boilers covered by the Boiler MACT rule (i.e., subpart DDDDD of CFR part 63). This document divides Boiler System conservation opportunities into four functional areas: 1) the boiler itself, 2) the condensate recovery system, 3) the distribution system, and 4) the end uses of the steam. This document provides technical information for documenting emissions credits proposed in the Implementation Plan for functional areas 2) though 4). This document does not include efficiency improvements related to the Boiler tune-ups.

  12. Corrosion Engineering.

    Science.gov (United States)

    White, Charles V.

    A description is provided for a Corrosion and Corrosion Control course offered in the Continuing Engineering Education Program at the General Motors Institute (GMI). GMI is a small cooperative engineering school of approximately 2,000 students who alternate between six-week periods of academic study and six weeks of related work experience in…

  13. Corrosion sensor

    Science.gov (United States)

    Glass, Robert S.; Clarke, Jr., Willis L.; Ciarlo, Dino R.

    1994-01-01

    A corrosion sensor array incorporating individual elements for measuring various elements and ions, such as chloride, sulfide, copper, hydrogen (pH), etc. and elements for evaluating the instantaneous corrosion properties of structural materials. The exact combination and number of elements measured or monitored would depend upon the environmental conditions and materials used which are subject to corrosive effects. Such a corrosion monitoring system embedded in or mounted on a structure exposed to the environment would serve as an early warning system for the onset of severe corrosion problems for the structure, thus providing a safety factor as well as economic factors. The sensor array is accessed to an electronics/computational system, which provides a means for data collection and analysis.

  14. 49 CFR 230.47 - Boiler number.

    Science.gov (United States)

    2010-10-01

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

  15. Stress corrosion cracking behaviour of gas tungsten arc welded super austenitic stainless steel joints

    OpenAIRE

    M. Vinoth Kumar; Balasubramanian, V.; S. RAJAKUMAR; Shaju K. Albert

    2015-01-01

    Super 304H austenitic stainless steel with 3% of copper posses excellent creep strength and corrosion resistance, which is mainly used in heat exchanger tubing of the boiler. Heat exchangers are used in nuclear power plants and marine vehicles which are intended to operate in chloride rich offshore environment. Chloride stress corrosion cracking is the most likely life limiting failure with austenitic stainless steel tubing. Welding may worsen the stress corrosion cracking susceptibility of t...

  16. Abatement of biofouling and corrosion in OTEC heat exchangers using low energy surfaces. Final technical report, May 1, 1975--February 29, 1976

    Energy Technology Data Exchange (ETDEWEB)

    Ostrozynski, R.L.; Jones, P.E.

    1976-06-01

    The economic viability of OTEC as a means of harnessing solar thermal energy depends on the ability to control marine fouling and corrosion on OTEC heat exchanger surfaces. During the past year under ERDA sponsorship, Allied Chemical Corporation demonstrated the concept that fouling and corrosion are minimized on low energy metal surfaces treated with fluorochemicals without impairing their heat transport properties. Experimentally, the surfaces of selected metals were chemically modified with a fluorochemical monolayer to minimize their surface energy. The treated metals were then observed for fouling and corrosion in the ocean at Miami, Florida in an attempt to simulate the OTEC operational environment. Antifouling and anticorrosion performance was judged by comparing the extent of barnacle, algae and corrosion coverage of the treated surface to one that was untreated. Other components, viz. tributyltin bearing agents and organoreactive silanes were combined with the fluorochemical in an effort to improve monolayer performance. Lower energy surfaces produced by a fluorochemical monolayer abated algae fouling on aluminum alloy No. 3003-H14 and commercially pure titanium throughout the test period of six weeks. Also, they protected the aluminum and 90/10 copper-nickel alloy No. 706 from seawater corrosion for the same duration. However, barnacle fouling was observed on all panel surfaces. Electron spectroscopic and electron microscopic analysis of the outermost surface pointed to the possible reasons for this growth. Evidently in most instances and particularly on titanium, the surfaces were not covered with a continuous film of monolayer. Moreover, the treatments left the surfaces with a rough texture and hence in a state predisposed to barnacle fouling.

  17. 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...

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

    Science.gov (United States)

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

    2013-06-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-06-30

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

  20. Corrosion-Activated Micro-Containers for Environmentally Friendly Corrosion Protective Coatings

    Science.gov (United States)

    Li, Wenyan; Buhrow, J. W.; Zhang, X.; Johnsey, M. N.; Pearman, B. P.; Jolley, S. T.; Calle, L. M.

    2016-01-01

    This work concerns the development of environmentally friendly encapsulation technology, specifically designed to incorporate corrosion indicators, inhibitors, and self-healing agents into a coating, in such a way that the delivery of the indicators and inhibitors is triggered by the corrosion process, and the delivery of self-healing agents is triggered by mechanical damage to the coating. Encapsulation of the active corrosion control ingredients allows the incorporation of desired autonomous corrosion control functions such as: early corrosion detection, hidden corrosion detection, corrosion inhibition, and self-healing of mechanical damage into a coating. The technology offers the versatility needed to include one or several corrosion control functions into the same coating.The development of the encapsulation technology has progressed from the initial proof-of-concept work, in which a corrosion indicator was encapsulated into an oil-core (hydrophobic) microcapsule and shown to be delivered autonomously, under simulated corrosion conditions, to a sophisticated portfolio of micro carriers (organic, inorganic, and hybrid) that can be used to deliver a wide range of active corrosion ingredients at a rate that can be adjusted to offer immediate as well as long-term corrosion control. The micro carriers have been incorporated into different coating formulas to test and optimize the autonomous corrosion detection, inhibition, and self-healing functions of the coatings. This paper provides an overview of progress made to date and highlights recent technical developments, such as improved corrosion detection sensitivity, inhibitor test results in various types of coatings, and highly effective self-healing coatings based on green chemistry. The NASA Kennedy Space Centers Corrosion Technology Lab at the Kennedy Space Center in Florida, U.S.A. has been developing multifunctional smart coatings based on the microencapsulation of environmentally friendly corrosion

  1. Cause Analysis and Technical Measures of Corrosion about the Chrome Plated Piston Rod of the Hydraulic Hoist%液压启闭机活塞杆锈蚀原因分析及技术措施

    Institute of Scientific and Technical Information of China (English)

    王煦; 吴舒海

    2013-01-01

    The service life of the cylinder related to the piston rod corrosion resistance directly. This paper presents analysis of corrosion causes about the chrome plated cylinder piston rod of the hydraulic hoist, and proposed some improving technical methods from the ma-terial of the piston rod and mechanical machining methods. These methods can enhance the corrosion resistance of the piston rod, and prolong its service life. Using different materials and dif erent process measures especial y stainless steel base material plating and ordi-nary steel spraying ceramic process can effectively prevent the piston rod rust, Water conservancy project hoist design selection should attach importance to the anticorrosion technology measures of hydraulic hoist piston rod.%启闭机油缸的使用寿命与活塞杆的耐腐蚀性能直接相关,现就液压启闭机镀铬活塞杆的锈蚀原因进行分析,并从活塞杆的材料与机械加工工艺等方面提出了改进技术措施,增强活塞杆的防腐蚀能力,能够延长启闭机的使用寿命。采用不同材质不同工艺措施,特别是不锈钢基材镀铬和普通钢材喷涂陶瓷工艺能够有效地防止活塞杆锈蚀,水利工程启闭机设计选型应对油缸活塞杆采取有效经济防腐工艺措施。

  2. Greener Approach towards Corrosion Inhibition

    Directory of Open Access Journals (Sweden)

    Neha Patni

    2013-01-01

    Full Text Available Corrosion control of metals is technically, economically, environmentally, and aesthetically important. The best option is to use inhibitors for protecting metals and alloys against corrosion. As organic corrosion inhibitors are toxic in nature, so green inhibitors which are biodegradable, without any heavy metals and other toxic compounds, are promoted. Also plant products are inexpensive, renewable, and readily available. Tannins, organic amino acids, alkaloids, and organic dyes of plant origin have good corrosion-inhibiting abilities. Plant extracts contain many organic compounds, having polar atoms such as O, P, S, and N. These are adsorbed on the metal surface by these polar atoms, and protective films are formed, and various adsorption isotherms are obeyed. Various types of green inhibitors and their effect on different metals are mentioned in the paper.

  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. Recent Corrosion Research Trends in Weld Joints

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hwan Tae; Kil, Sang Cheol [Korea Institute of Science and Technology Information, Seoul (Korea, Republic of); Hwang, Woon Suk [Inha University, Incheon (Korea, Republic of)

    2007-04-15

    The increasing interest in the corrosion properties of weld joints in the corrosive environment is placing stringent demands on the manufacturing techniques and performance requirements, and the manufacture employs the high quality and efficiency welding process to produce welds. Welding plays an important role in the fabrication of chemical plants, nuclear power plant, ship construction, and this has led to an increasing attention to the corrosion resistant weld joints. This paper covers recent technical trends of welding technologies for corrosion resistance properties including the COMPENDEX DB analysis of welding materials, welding process, and welding fabrications

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

    Science.gov (United States)

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

    2012-01-01

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

  6. Internal corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Joosten, M. [ConocoPhillips, Bartlesville, OK (United States); Anderson, W. [Spectra Energy Transmission, Vancouver, BC (Canada)

    2007-07-01

    Working Group 11 identified internal corrosion issues in both upstream and downstream oil and gas pipelines and suggested ways to address them through integrity management, modeling, and monitoring. Three sessions were held in an effort to provided a better understanding between integrity professionals engaged in different aspects of pipeline management. Opportunities for reducing cost or improving integrity performance of the whole system were also identified. It was determined that management support is needed in order to monitor and mitigate internal corrosion of pipelines. The role of regulations in ensuring pipeline integrity was also discussed along with rules for pigging and batching of inhibitors. In-line inspections have identified under-deposit corrosion and solids/water deposition as two key problems facing pipeline operators. It was noted that an internal corrosion course offered by the National Association of Corrosion Engineers (NACE) is being well attended and is providing worthwhile training. Other issues discussed by this working group were: bacteria with upstream problems; effects of carbon dioxide, hydrogen sulphide and partial pressures on corrosion; and, procedures and guidelines to maintain clean pipelines. tabs., figs.

  7. Corrosion and Materials Performance in biomass fired and co-fired power plants

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Larsen, OH; Biede, O

    2003-01-01

    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. In woodchip boilers, a similar corrosion rate and corrosion mechanism has on some occasions been observed. Co-firing of straw (10...... and 20% energy basis) with coal has shown corrosion rates lower than those in straw-fired plants. With both 10 and 20% straw, no chlorine corrosion was seen. This paper will describe the results from in situ investigations undertaken in Denmark on high temperature corrosion in biomass fired plants....... Results from 100% straw-firing, woodchip and co-firing of straw with coal will be reported. The corrosion mechanisms observed are summarized and the corrosion rates for 18-8 type stainless steels are compared....

  8. Energy-saving Technical Renovation on Boiler Induced-draft Fan Using High Voltage Variable Frequency Technology%锅炉引风机采用高压变频技术的节能效果

    Institute of Scientific and Technical Information of China (English)

    何幼富

    2011-01-01

    This paper introduces the original operation status of 2×125 MW units of a power plant and explains the application of high voltage varable frequency in the energy - saving renovation of the boiler induced - draft fan. Practical data proved the sufficiency of the proposed method.%介绍了某电厂2×125 MW机组锅炉引风机的原有设备运行情况,阐述了高压变频调速装置在锅炉引风机改造上的节能应用,用实际数据证明了引风机变频调速运行的节能效果.

  9. Role of HVOF-spray NiCr coatings to control high temperature oxidation of some boiler steels

    Energy Technology Data Exchange (ETDEWEB)

    Kaushal, G. [RIMT-Institute of Engineering and Technology, Mandi Gobind Garh (India); Singh, H. [BBSB Engineering College, Fatehgarh Sahib (India); Prakash, S. [Indian Inst. of Technology, Roorkee (India)

    2008-07-01

    A study was carried out to determine the role of HVOF-spray Ni-20Cr coatings to enhance high temperature oxidation resistance of T22 and 347H boiler steels. Ni-20Cr coatings were deposited on the boiler steels. Subsequently high temperature oxidation behavior of these coatings was investigated by laboratory tests at an elevated temperature of 900 C under cyclic conditions.These coatings were also subjected to a boiler environment at an elevated temperature of 700 C under cyclic conditions to ascertain their erosion-corrosion behaviour. Thermogravimetric data was taken after each cycle to formulate the oxidation, as well as, erosion-corrosion kinetics. The specimens were also physically examined after each cycle to notice any macrographic physical changes, spallation tendency of their oxide scales etc. The exposed specimens were examined using scanning electron microscopy and Energy Dispersive Spectroscopy (SEM/EDS) analysis. It was observed that oxidation rate was subsequently low in the coated substrates as compare to uncoated steels. It was observed that Ni-20Cr coating on 347H boiler substrate showed the maximum oxidation resistance. Moreover, both the steels showed better resistance to erosion-corrosion in actual boiler conditions after the application of Ni-20Cr coating. (orig.)

  10. 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.

  11. High temperature corrosion in straw-fired power plants: Influence of steam/metal temperature on corrosion rates for TP347H

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Biede, O; Larsen, OH

    2002-01-01

    The corrosion in straw-fired boilers has been investigated at various straw-fired power plants in Denmark. Water/air-cooled probes, a test superheater and test sections removed from the actual superheater have been utilised to characterise corrosion and corrosion rates. This paper describes...... the corrosion rates measured for the TP347H type steel. The corrosion morphology at high temperature consists of grain boundary attack and selective attack of chromium. The corrosion rate increases with calculated metal temperature (based on steam temperature), however there is great variation within...... these results. In individual superheaters, there are significant temperature variations i.e. higher temperature in middle banks compared to the outer banks, higher temperature in leading tubes, which have a high impact on corrosion. In a single loop the assumption that heat uptake (and heat flux) is linear...

  12. Corrosion potential analysis system

    Science.gov (United States)

    Kiefer, Karl F.

    1998-03-01

    Many cities in the northeastern U.S. transport electrical power from place to place via underground cables, which utilize voltages from 68 kv to 348 kv. These cables are placed in seamless steel pipe to protect the conductors. These buried pipe-type-cables (PTCs) are carefully designed and constantly pressurized with transformer oil to prevent any possible contamination. A protective coating placed on the outside diameter of the pipe during manufacture protects the steel pipe from the soil environment. Notwithstanding the protection mechanisms available, the pipes remain vulnerable to electrochemical corrosion processes. If undetected, corrosion can cause the pipes to leak transformer oil into the environment. These leaks can assume serious proportions due to the constant pressure on the inside of the pipe. A need exists for a detection system that can dynamically monitor the corrosive potential on the length of the pipe and dynamically adjust cathodic protection to counter local and global changes in the cathodic environment surrounding the pipes. The northeastern United States contains approximately 1000 miles of this pipe. This milage is critical to the transportation and distribution of power. So critical, that each of the pipe runs has a redundant double running parallel to it. Invocon, Inc. proposed and tested a technically unique and cost effective solution to detect critical corrosion potential and to communicate that information to a central data collection and analysis location. Invocon's solution utilizes the steel of the casing pipe as a communication medium. Each data gathering station on the pipe can act as a relay for information gathered elsewhere on the pipe. These stations must have 'smart' network configuration algorithms that constantly test various communication paths and determine the best and most power efficient route through which information should flow. Each network station also performs data acquisition and analysis tasks that ultimately

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-06-21

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

  14. CORROSION IN AIRFRAMES

    OpenAIRE

    PETROVIC ZORAN C.

    2016-01-01

    The introductory chapter provides a brief reference to the issue of corrosion and corrosion damage to aircraft structures. Depending on the nature and dimensions of this non uniformity, three different categories of corrosion are defined: uniform, selective and localized corrosion. The following chapters present the forms of corrosion that can occur in three defined categories of corrosion. Conditions that cause certain types of corrosion in various corrosive environments are discussed. Examp...

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

    Science.gov (United States)

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

    2015-02-01

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

  16. Corrosion amalgams

    International Nuclear Information System (INIS)

    The release of copper, mercury, silver, tin or zinc from conventional, dispersed phase and spherical high copper content amalgams immersed in artificial saliva solutions for periods up to 30 d has been measured using nuclear tracer techniques. During initial corrosion, i.e. within a few hours, substantial amounts of mercury were found to be present in particulate matter in the three types of amalgams. The release of particulate matter was pronounced for the dispersed phase type of amalgam. After about 30 d electrochemical corrosion was found to be the predominant process for release of various corrosion products. Zinc was demonstrated to be the major corrosion product released to the artificial saliva solutions from conventional as well as dispersed phase amalgams. Due to low radioactivity levels silver and tin could not be quantitatively asayed. However, the upper limits of release of silver and tin in the artificial saliva solutions referring to exposure periods up to 30 d were estimated to 0.1 μg and 25 μg respectively. The chemical state of the various corrosion products has been evaluated. The deposition of CuCl2 . 3 Cu(OH)2 on the surfaces of copper rich amalgams was observed according to X-ray diffraction analysis. (author)

  17. Production of high quality distillate to meet a fit-for-purpose boiler feedwater specification

    Energy Technology Data Exchange (ETDEWEB)

    Minnich, K. [Veolia Water Solutions Oil and Gas, Calgary, AB (Canada); Neu, D. [Veolia Water Solutions and Technologies/HPD, Pewaukee, WI (United States); Drone, J.L. [Veolia Water Solutions and Technologies/HPD, Plainfield, IL (United States)

    2009-07-01

    Veolia Water Solutions and Technologies has significant experience managing boiler water chemistry and is the world's largest manufacturer of evaporation systems. The company has conducted extensive testing and analysis for produced water evaporation distillate from multiple facilities. In order to produce boiler feed water, evaporation of produced water is used at several steam assisted gravity drainage (SAGD) facilities. There are no official guidelines for the required quality of evaporator distillate to feed a once through steam generator (OTSG) or high pressure industrial watertube boiler (IWT) that will produce injection steam. This paper presented a basis for a fit-for-purpose specification for IWT boilers as well as data on the performance of a Vapor Washer, which produces high quality distilled water that meets fit-for-purpose specifications even during normal variations in feed conditions. Specifically, the paper discussed boiler water requirements for steam injection IWTs; the quality of distillate from a produced water evaporator; the benefits of vapour washing to maintain distillate quality; and suggested boiler chemistry limits for a fit-for-purpose specification. Oxygen, iron, and copper were discussed as being implicated with corrosion and reaction in boilers. Hardness contaminants such as calcium and magnesium were also presented. Suggested limits for boiler water in the fit-for-purpose specification were also presented for silica, total alkalinity, free OH alkalinity, and total dissolved solids in steam. It was concluded that foaming episodes can occur in produced water evaporators due to normal variations, and the distillate can fail to meet the fit-for-purpose specification during foam upsets. 3 refs., 9 figs.

  18. New controls spark boiler efficiency

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-09-01

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

  19. 10 CFR 431.82 - Definitions concerning commercial packaged boilers.

    Science.gov (United States)

    2010-01-01

    ... pressure boiler means a packaged boiler that is: (1) A steam boiler designed to operate at a steam pressure... steam boiler designed to operate at or below a steam pressure of 15 psig; or (2) A hot water boiler... 10 Energy 3 2010-01-01 2010-01-01 false Definitions concerning commercial packaged boilers....

  20. Nickel-chromium plasma spray coatings: A way to enhance degradation resistance of boiler tube steels in boiler environment

    Energy Technology Data Exchange (ETDEWEB)

    Sidhu, B.S.; Prakash, S.

    2006-03-15

    Boiler tube steels, namely low carbon steel ASTM-SA210-Grade A1 (GrA1), 1Cr-0.5Mo steel ASTM-SA213-T-11 (T11), and 2.25Cr-1Mo steel ASTM-SA213-T-22 (T22), were used as substrate steels. Ni-22Cr-10AI-1Y powder was sprayed as a bond coat 150 {mu}m thick before a 200 {mu}m final coating of Ni-20Cr was applied. Coatings were characterized prior to testing in the environment of a coal fired boiler. The uncoated and coated steels were inserted in the platen superheater zone of a coal fired boiler at around 755{sup o}C for 10 cycles, each 100 h. Coated steels showed lower degradation (erosion-corrosion) rate than uncoated steels showed. The lowest rate was observed in the case of Ni-20Cr coated T11 steel. Among the uncoated steels, the observed rate of degradation was the lowest for the T22 steel.

  1. Nickel-chromium plasma spray coatings: A way to enhance degradation resistance of boiler tube steels in boiler environment

    Science.gov (United States)

    Sidhu, Buta Singh; Prakash, S.

    2006-03-01

    Boiler tube steels, namely low carbon steel ASTM-SA-210-Grades A1 (GrA1), 1Cr-0.5Mo steel ASTM-SA213-T-11 (T11), and 2.25Cr-1 Mo steel ASTM-SA213-T-22(T22), were used as substrate steels. Ni-22Cr-10Al-1Y powder was sprayed as a bond coat 150 μm thick before a 200 μm final coating of Ni-20Cr was applied Coatings were characterized prior to testing in the environment of a coal fire boiler. The uncoated and coated steels were inserted in the platen superheater zone of a coal fired boiler at around 755°C for 10 cycles, each 100 h. Coated steels showed lower degradation (erosion-corrosion) rate than uncoated steels showed. The lowest rate was observed in the case of Ni-20Cr coated T11 steel. Among the uncoated steels, the observed rate of degradation was the lowest for the T22 steel.

  2. Fireside corrosion testing of candidate superheater tube alloys, coatings, and claddings - phase II

    Energy Technology Data Exchange (ETDEWEB)

    Blough, J.L.; Stanko, G.J. [Foster Wheeler Development Corp., Livingston, NJ (United States)

    1996-08-01

    In Phase I a variety of developmental and commercial tubing alloys and claddings were exposed to laboratory fireside corrosion testing simulating a superheater or reheater in a coal-fired boiler. Phase II (in situ testing) has exposed samples of 347, RA-8511, HR3C, 253MA, Fe{sub 3}Al + 5Cr, 310 modified, 800HT, NF 709, 690 clad, and 671 clad for over 10,000 hours to the actual operating conditions of a 250-MW coal-fired boiler. The samples were installed on an air-cooled, retractable corrosion probe, installed in the reheater cavity, and controlled to the operating metal temperatures of an existing and advanced-cycle coal-fired boiler. Samples of each alloy will be exposed for 4000, 12,000, and 16,000 hours of operation. The results will be presented for the metallurgical examination of the corrosion probe samples after 4000 hours of exposure.

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

    Science.gov (United States)

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

    2015-04-01

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

  4. MODELLING, SIMULATING AND OPTIMIZING BOILERS

    DEFF Research Database (Denmark)

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

    2003-01-01

    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 the internal pressure the consequence of the increased volume (i.e. water-/steam space) is an increased wall thickness in the pressure part of the boiler. The stresses introduced in the boiler pressure part as a result of the temperature gradients are proportional to the square of the wall thickness......, 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...

  5. Ventilation in medium-sized and large boiler houses; Ventilation i medelstora och stoerre pannhus

    Energy Technology Data Exchange (ETDEWEB)

    Grotherus, Dan [AaF Installation AB, Oerebro (Sweden); Larsson, Tord [Oerebro Univ. (Sweden). Dept. of Technology

    2005-04-01

    pressure in the lower part of the boiler house should not exceed approximately 40 Pa. This is to minimize problems with inleaking of odours and particles into the boiler house and to facilitate the evacuation of the staff from the boiler house. Issues concerning boiler house ventilation will appear in different stages at new construction and conversion projects. During the feasibility study the ventilation requirements are investigated and possible solutions are outlined. The planning stage involves the establishing of the ventilation requirements, technical solutions and the investment needs. Investment expenditure for the installation of a mechanized ventilation system varies depending on the size of the boiler, the choice of ventilation solution etc. Experiences from three recently built plants show that capital expenditure for the ventilation systems in these plants amounts to approximately SEK 140,000/MW (about 18,000 USD/MW) for a boiler effect of approximately 50 MW.

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

    Energy Technology Data Exchange (ETDEWEB)

    Levasseur, Armand

    2014-04-30

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

  7. 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

  8. Optimizing the integrated design of boilers - simulation

    DEFF Research Database (Denmark)

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

    2004-01-01

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

  9. 29 CFR 1915.162 - Ship's boilers.

    Science.gov (United States)

    2010-07-01

    ... Ship's boilers. (a) Before work is performed in the fire, steam, or water spaces of a boiler where employees may be subject to injury from the direct escape of a high temperature medium such as steam, or... 29 Labor 7 2010-07-01 2010-07-01 false Ship's boilers. 1915.162 Section 1915.162 Labor...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-31

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

  11. Investigation and analysis of short overheat in boiler tube failure in power plant units

    International Nuclear Information System (INIS)

    Boiler tube failure are the main cause of forced outages of power generating units and due to cost, Penalty is very high. Sources and reasons of tube failures are various, but it can be generally categorized by mechanical and corrosion factors with 81% and 19% contributions, respectively. Among the mechanical factors short overheat has the major contribution in water wall and superheater tube, failure. In this paper short overheat mechanism (with appearance and metallurgical features) and its prevention method is over viewed

  12. Stress corrosion cracking experience in steam generators at Bruce NGS

    International Nuclear Information System (INIS)

    In late 1990 and through 1991, units 1 and 2 at the Bruce A Nuclear Generating Station (BNGS-A) experienced a number of steam generator tube leaks. Tube failures were identified by eddy current to be circumferential cracks at U-bend supports on the hot-leg side of the boilers. In late 1991, tubes were removed from these units for failure characterization. Two active failure modes were found: corrosion fatigue in both units 1 and 2 and stress corrosion cracking (SCC) in unit 2. In unit 2, lead was found in deposits, on tubes, and in cracks, and the cracking was mixed-mode: transgranular and intergranular. This convincingly indicated the involvement of lead in the stress corrosion cracking failures. A program of inspection and tube removals was carried out to investigate more fully the extent of the problem. This program found significant cracking only in lead-affected boilers in unit 2, and also revealed a limited extent of non-lead-related intergranular stress corrosion cracking in other boilers and units. Various aspects of the failures and tube examinations are presented in this paper. Included is discussion of the cracking morphology, measured crack size distributions, and chemical analysis of tube surfaces, crack faces, and deposits -- with particular emphasis on lead

  13. Underground pipeline corrosion

    CERN Document Server

    Orazem, Mark

    2014-01-01

    Underground pipelines transporting liquid petroleum products and natural gas are critical components of civil infrastructure, making corrosion prevention an essential part of asset-protection strategy. Underground Pipeline Corrosion provides a basic understanding of the problems associated with corrosion detection and mitigation, and of the state of the art in corrosion prevention. The topics covered in part one include: basic principles for corrosion in underground pipelines, AC-induced corrosion of underground pipelines, significance of corrosion in onshore oil and gas pipelines, n

  14. Screening and Quantification of Aliphatic Primary Alkyl Corrosion Inhibitor Amines in Water Samples by Paper Spray Mass Spectrometry.

    Science.gov (United States)

    Jjunju, Fred P M; Maher, Simon; Damon, Deidre E; Barrett, Richard M; Syed, S U; Heeren, Ron M A; Taylor, Stephen; Badu-Tawiah, Abraham K

    2016-01-19

    Direct analysis and identification of long chain aliphatic primary diamine Duomeen O (n-oleyl-1,3-diaminopropane), corrosion inhibitor in raw water samples taken from a large medium pressure water tube boiler plant water samples at low LODs (water samples was confirmed via tandem mass spectrometry using collision-induced dissociation and supported by exact mass measurement and reactive paper spray experiments using an LTQ Orbitrap Exactive instrument. Data shown herein indicate that paper spray ambient ionization can be readily used as a rapid and robust method for in situ direct analysis of polymanine corrosion inhibitors in an industrial water boiler plant and other related samples in the water treatment industry. This approach was applied for the analysis of three complex water samples including feedwater, condensate water, and boiler water, all collected from large medium pressure (MP) water tube boiler plants, known to be dosed with varying amounts of polyamine and amine corrosion inhibitor components. Polyamine chemistry is widely used for example in large high pressure (HP) boilers operating in municipal waste and recycling facilities to prevent corrosion of metals. The samples used in this study are from such a facility in Coventry waste treatment facility, U.K., which has 3 × 40 tonne/hour boilers operating at 17.5 bar. PMID:26727190

  15. Recent Developments on Microencapsulation for Autonomous Corrosion Protection

    Science.gov (United States)

    Calle, Luz M.; Li, Wenyan; Buhrow, Jerry W.; Fitzpatrick, Lilliana; Jolley, Scott T.; Surma, Jan M.; Pearman, Benjamin P.; Zhang, Xuejun

    2014-01-01

    This work concerns recent progress in the development of a multifunctional smart coating based on microencapsulation for the autonomous control of corrosion. Microencapsulation allows the incorporation of desired corrosion control functionalities, such as early corrosion detection and inhibition through corrosion controlled release of corrosion indicators and inhibitors, as well as self-healing agent release when mechanical damage occurs.While proof-of-concept results have been reported previously, more recent efforts have been concentrated in technical developments to improve coating compatibility, synthesis procedure scalability, as well as fine tuning the release property of encapsulated active agents.

  16. 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...

  17. Superheater materials for waste incinerator boilers. Trials at the Hoegdalen plant

    International Nuclear Information System (INIS)

    In order to obtain an acceptable length of life for the superheaters in waste incinerated boilers a considerably lower steam temperature is used than when incinerating conventional fuel. In spite of this the life of the superheaters is unsatisfactory, with the occurrence of damage in some type of incinerator boilers after only a few years operation. The use of high alloyed material instead of conventional pressure vessel steels can increase the length of life and improve operational efficiency in existing incinerator boilers. Such tubes permit higher steam data for new plants. Cooled materials testing probes have been mounted in the flue gas duct close to the superheater in two boilers in the Hoegdalen plant, Stockholm. The materials temperatures have been maintained in the range 400-500 degrees C. Low metal losses have been obtained, in particular with Alloy 625, but also with Alloy 825 and Sandvik Sanicro 28. The attack on the tubes is corrosion, caused by the aggressive dust which is trapped in the superheaters. In these trials it has been shown that correct boiler design is very important, in conjunction with the choice of materials

  18. Superheater materials for waste incinerator boilers. Trials at the Hoegdalen plant

    Energy Technology Data Exchange (ETDEWEB)

    Haeggblom, E.

    1992-12-01

    In order to obtain an acceptable length of life for the superheaters in waste incinerated boilers a considerably lower steam temperature is used than when incinerating conventional fuel. In spite of this the life of the superheaters is unsatisfactory, with the occurrence of damage in some type of incinerator boilers after only a few years operation. The use of high alloyed material instead of conventional pressure vessel steels can increase the length of life and improve operational efficiency in existing incinerator boilers. Such tubes permit higher steam data for new plants. Cooled materials testing probes have been mounted in the flue gas duct close to the superheater in two boilers in the Hoegdalen plant, Stockholm. The materials temperatures have been maintained in the range 400-500 degrees C. Low metal losses have been obtained, in particular with Alloy 625, but also with Alloy 825 and Sandvik Sanicro 28. The attack on the tubes is corrosion, caused by the aggressive dust which is trapped in the superheaters. In these trials it has been shown that correct boiler design is very important, in conjunction with the choice of materials.

  19. Advanced, Low/Zero Emission Boiler Design and Operation

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-06-30

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

  20. General Corrosion and Localized Corrosion of the Drip Shield

    Energy Technology Data Exchange (ETDEWEB)

    F. Hua

    2004-09-16

    The repository design includes a drip shield (BSC 2004 [DIRS 168489]) that provides protection for the waste package both as a barrier to seepage water contact and a physical barrier to potential rockfall. The purpose of the process-level models developed in this report is to model dry oxidation, general corrosion, and localized corrosion of the drip shield plate material, which is made of Ti Grade 7. This document is prepared according to ''Technical Work Plan For: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]). The models developed in this report are used by the waste package degradation analyses for TSPA-LA and serve as a basis to determine the performance of the drip shield. The drip shield may suffer from other forms of failure such as the hydrogen induced cracking (HIC) or stress corrosion cracking (SCC), or both. Stress corrosion cracking of the drip shield material is discussed in ''Stress Corrosion Cracking of the Drip Shield, the Waste Package Outer Barrier, and the Stainless Steel Structural Material'' (BSC 2004 [DIRS 169985]). Hydrogen induced cracking of the drip shield material is discussed in ''Hydrogen Induced Cracking of Drip Shield'' (BSC 2004 [DIRS 169847]).

  1. Peculiar high temperature corrosion of martensite alloy under impact of Estonian oil shale fly ash

    Energy Technology Data Exchange (ETDEWEB)

    Tallermo, H.; Klevtsov, I. [Thermal Engineering Department of Tallinn Technical University, Tallinn (Estonia)

    1998-12-31

    The superheaters` surfaces of oil shale steam boiler made of pearlitic and austenitic alloys, are subject to intensive corrosion, mainly due to presence of chlorine in external deposits. The applicability of martensitic alloys X1OCrMoVNb91 and X20CrMoV121 for superheaters is examined here and empirical equations allowing to predict alloys` corrosion resistance in the range of operational temperatures are established. Alloy X1OCrMoVNb91 is found been most perspective for superheaters of boilers firing fossil fuel that contain alkaline metals and chlorine. The abnormal dependence of corrosion resistance of martensitic alloys on temperature is revealed, namely, corrosion at 580 deg C in presence of oil shale fly ash is more intensive than at 620 deg C. (orig.) 2 refs.

  2. Corrosion behaviour of non-ferrous metals in sea water

    Energy Technology Data Exchange (ETDEWEB)

    Birn, Jerzy; Skalski, Igor [Ship Design and Research Centre, Al. Rzeczypospolitej 8, 80-369 Gdansk (Poland)

    2004-07-01

    caused by a significant difference of corrosion potentials of aluminium alloy and most of metals used in technical applications. Exfoliation is observed mainly in case of Al-Zn-Mg alloys after welding. Corrosion in the presence of OH- ions occurs usually as an effect of application of cathodic protection of aluminium alloys in the over-protected zone. For most of the above mentioned alloys models of corrosion phenomena are presented. Furthermore, the long term prediction of applied alloys life in sea water is discussed. At the end of the paper areas of future studies are presented. (authors)

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

    Directory of Open Access Journals (Sweden)

    Diego L. Sepúlveda M

    2011-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-12-31

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

  5. Synergistic Application of Chemical and Electromagnetic Water Treatment in Corrosion and Scale Prevention

    OpenAIRE

    Čolić, Miroslav; Chien, Allen; Morse, Dwain

    1998-01-01

    The costs of damage caused by scale and corrosion worldwide in cooling towers, boilers and pipes escalated to more than an annual $100 billion in recent years. Neither classical chemical prevention methods nor new alternative electromagnetic water treatment methods have yielded satisfying solutions. We have used a combination of chemical and electromagnetic technologies to prevent scale and corrosion of galvanized zinc coated cooling towers with great success in the last three years. This man...

  6. Combating corrosion in biomass and waste-fired plant

    OpenAIRE

    Henderson, Pamela; Hjörnhede, Anders

    2010-01-01

    Many biomass- or waste-fired plants have problems with high temperature corrosion especially if the steam temperature is greater than500°C.  An increase in the combustion of waste fuels means that an increasing number of boilers have had problems. Therefore, there is great interest in reducing the costs associated with high temperature corrosion and at the same time there exists a desire to improve the electrical efficiency of a plant by the use of higher steam temperatures.  Assuming that th...

  7. 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...

  8. Evaluation of electrochemical techniques for measurement of fireside corrosion in thermal power plants; Utvaerdering av elektrokemiska tekniker foer maetning av roekgassidig hoegtemperaturkorrosion i pannor

    Energy Technology Data Exchange (ETDEWEB)

    Hjorrnhede, Anders

    2007-12-15

    The possibility to measure the corrosion rate on-line, in situ, is getting more and more interesting due to increased corrosion. The worsening may be a result of lower fuel quality or increased steam data due to raised efficiency demands. Also the use of inhibitors can be improved and the lifetime of important components can be increased. Today, virtually all corrosion measurements of materials used for waterwalls, superheaters, economisers and other heat-transferring surfaces are based on in-situ probe tests of coupons or rings. The aim of the project is to evaluate the practicability of commercial or semicommercial on-line in-situ corrosion probes for use in waste fired boilers. The target groups are owners of boilers, operators, service personnel but also boiler manufacturer and material producers. Since the use of on-line, in situ, corrosion probes is substantial, some of the most promising corrosion probes have been tested in a waste fired boiler in Hamburg, Germany. Tests in waste fired boiler have never before been performed. The MECO CB, a Linear Polarisation Resistance (LPR) corrosion probe from Coresto Oy, Finland was tested and from Lehrstuhl fuer Umweltverfahrenstechnik und Anlagentechnik (LUAT) der Universitaet Duisburg-Essen, Germany an Electrochemical Noise (EN) - probe was tested. From Pepperl + Fuchs both EN- and LPR-CorrTran corrosion sensors were tested. The test periods were lasting from 1050h to 3750h. The test materials were the low alloyed steel 15Mo3, the Ni-based super alloys Sanicro 63 and Haynes Hastelloy C-2000. The fluegas temperatures were 635 deg C or 520 deg C. The material temperatures were 440 deg C, 420 deg, 350 deg C and was swept from 400 deg C to 300 deg C. All probes are measuring a signal which has a correlation to the corrosion process, but the quantification procedure is not working well. The results achieved from the corrosion probes must be calibrated against corrosion rates measured by means of conventional corrosion

  9. 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)

  10. 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)

  11. 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.

  12. Hot Corrosion Behaviour of Detonation Gun Sprayed Al2O3-40TiO2 Coating on Nickel Based Superalloys at 900°C

    OpenAIRE

    N. K. Mishra; Naveen Kumar; S. B. Mishra

    2014-01-01

    Hot corrosion is the major degradation mechanism of failure of boiler and gas turbine components. These failures occur because of the usage of wide range of fuels such as, coal and oil at the elevated temperatures. Nickel based superalloys having excellent mechanical strength and creep resistance at elevated temperature are used under such environment but they lack resistance to hot corrosion at high temperature. To overcome these problems hot corrosion resistant coatings are deposited on the...

  13. The oxidation mechanism of szomolnokite in intermittently fired domestic boilers

    Energy Technology Data Exchange (ETDEWEB)

    Koebel, M.; Elsener, M.; Zimmermann, U.

    1989-06-01

    Using thermogravimetry and exposure experiments on initially formed iron (II)-sulfate hydrates the consecutive reactions of the primary corrosion product szomolnokite under the typical operating conditions of domestic boilers were investigated. The reaction mechanism thus deduced is in accordance with thermodynamic equilibrium considerations in the system Fe/sub 2/O/sub 3/-H/sub 2/SO/sub 4/-H/sub 2/O/crystalline phase. The reaction mechanism consists of the following steps: (1) H/sub 2/SO/sub 4/ (vapour) -> H/sub 2/SO/sub 4/ (liquid). (2) H/sub 2/SO/sub 4/ + Fe + H/sub 2/O -> FeSO/sub 4/xH/sub 2/O + H/sub 2/. (3) 2FeSO/sub 4/xH/sub 2/O + 0,5 O/sub 2/ -> 2Fe(OH)SO/sub 4/ + H/sub 2/O. (4a) Fe(OH)SO/sub 4/ + H/sub 2/SO/sub 4/ + 3H/sub 2/O -> FeH(SO/sub 4/)/sub 2/x4H/sub 2/O. (4b) Fe(OH)SO/sub 4/ + H/sub 2/SO/sub 4/ -> Fe(H/sub 3/O)(SO/sub 4/)/sub 2/. (5a) 2FeH(SO/sub 4/)/sub 2/x4H/sub 2/O -> Fe/sub 2/(SO/sub 4/)/sub 3/ + H/sub 2/SO/sub 4/ + 8H/sub 2/O. (5b) 2Fe(H/sub 3/O)(SO/sub 4/)/sub 2/ -> Fe/sub 2/ (SO/sub 4/)/sub 3/ + H/sub 2/SO/sub 4/ + 2 H/sub 2/O. With this reaction mechanism the most frequently occurring crystalline phases in corrosion samples from oil fired domestic boilers can be explained. (orig.).

  14. One Method of Solving Boiler Water wall Tubes High Temperture Gorrosion & Erosion%解决锅炉水冷壁管高温腐蚀和

    Institute of Scientific and Technical Information of China (English)

    胡双南; 许宏宇

    2009-01-01

    Adopting heat spray technique is a reliable method to solve boiler water wall tubes corrosion & erosion.%采用热喷涂技术是火电厂锅炉水冷壁高温防腐耐磨涂层最可靠的解决方法之一.

  15. Superheater materials for better energy efficiency, lower emissions and better fuel flexibility in recovery and bark boilers; Oeverhettarmaterial foer energieffektivare, miljoevaenligare och braensleflexiblare sodahus- och barkpannor

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, Thomas; Falk, Ivan [Studsvik Material AB, Nykoeping (Sweden)

    1999-11-01

    The corrosion behaviour for a number of tube materials was studied in a kraft recovery boiler. Low and high alloyed ferritic materials together with low and high alloyed austenitic materials were investigated. Exposures were performed at Stora Ensos plant at Norrsundet, boiler 65, in the superheater section. Corrosion probes were exposed for 250 hours using a material temperature gradient over the test section in the range 430-550 deg C. Light optical microscopy were used for the metallographic evaluation. It was found that the austenitic materials show a better corrosion resistance compared to the ferritic materials. Sanicro 28 forms a passivating oxide in the temperature range investigated and is the material that shows the best corrosion properties in the investigation. 304L forms a partly passivating oxide that decrease the corrosion rate significantly in the entire temperature range. These two materials show only a weak temperature dependence. The corrosion behaviour of the ferritic materials are much more sensible to the temperature and the reaction resistance is reduced as the temperature increase. Even at the lowest temperatures the ferritic materials are worse than the austenitic but the difference is not remarkable. The ferritic materials do not form a passivating oxide. Compared to ordinary fossil and biomass combustion, recovery boilers constitutes a more difficult environment for corrosion probe investigations. Established techniques used in power producing utilities shows their limitations in the recovery boiler. E.g. a thermocouple measuring the material temperature is normally used to control the cooling efficiency to the probe but due to the properties of the deposits other solutions might give a more representative result. One plausible solution is to use the temperature on the exhaust air as input data for the control system. Such a solution could be of interest for use in power producing utilities since it might be a more representative way to

  16. High Temperature Corrosion of Superheater Materials for Power Production through Biomass

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Maahn, Ernst emanuel; Nielsen, Karsten agersted;

    plant boiler. The experiments using this facility includes corrosion studies of two types of high temperature resistant steels, Sandvik 8LR30 (18Cr 10Ni Ti) and Sanicro 28 (27Cr 31Ni 4Mo)investigated at 600Cin time intervals up to 300 hours. The influence of HCl (200ppm) and of SO2 (300 ppm...

  17. IN DRIFT CORROSION PRODUCTS

    Energy Technology Data Exchange (ETDEWEB)

    D.M. Jolley

    1999-12-02

    As directed by a written development plan (CRWMS M&O 1999a), a conceptual model for steel and corrosion products in the engineered barrier system (EBS) is to be developed. The purpose of this conceptual model is to assist Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department in modeling the geochemical environment within a repository drift, thus allowing PAO to provide a more detailed and complete in-drift geochemical model abstraction and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near-Field Environment (NFE) Revision 2 (NRC 1999). This document provides the conceptual framework for the in-drift corrosion products sub-model to be used in subsequent PAO analyses including the EBS physical and chemical model abstraction effort. This model has been developed to serve as a basis for the in-drift geochemical analyses performed by PAO. However, the concepts discussed within this report may also apply to some near and far-field geochemical processes and may have conceptual application within the unsaturated zone (UZ) and saturated zone (SZ) transport modeling efforts.

  18. Failure Analysis of 600 MW Supercritical Boiler Water Wall

    Directory of Open Access Journals (Sweden)

    Fu Huilin

    2013-07-01

    Full Text Available 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 burst pipe. Analysis of the deformation of the boiler and propose solutions.

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

    Science.gov (United States)

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

    2012-05-01

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

  20. 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.

  1. Re-burning of ash in grate boilers; Omfoerbraenning av askor i rosterpannor

    Energy Technology Data Exchange (ETDEWEB)

    Bergqvist, Kristina; Myringer, Aase; Nordgren, Daniel; Rydberg, Stina [Vattenfall Utveckling AB, Aelvkarleby (Sweden)

    2005-03-01

    High contents of unburnt carbon in ashes that are dumped or recycled, is questionable from both an economical and an environmental point of view. The content of unburnt carbon in bottom and fly ash from grate boilers varies greatly between different plants but can sometimes exceed 50 %. Re-burning of ash that is separated before a final dust separation, is a relatively cheep and simple method for reducing the content of unburnt carbon in ash, which both reduces the fuel cost and the deposit cost, i.e. the cost of landfilling or recycling. As from 2005 it is prohibited to deposit ash with a too high content of unburnt organic material; the content is limited to 18 weight % of unburnt carbon. The study was carried out in two phases. The aim of the first phase was to map the different techniques used for re-burning ash that are used in grate boilers today. The mapping was done through telephone interviews and comprises technical descriptions of the systems, gathering of operational know-how, installations costs and the effect of the systems on the amount of ash generated at the plants and the content of unburnt carbon in the ash. In order to accomplish a deeper technical and economical evaluation of ash re-burning systems, the second phase involved field studies at two plants. In addition screening tests were done to investigate the connection between the content of unburnt carbon and particle size. The potential of reducing the amount of circulated inorganic material by sieving the ash before bringing it back to the furnace could thereby be determined. 13 plants that utilize re-burning of ash were identified, of which two plants re-burn the bottom ash that floats up to the surface in the wet ash removal system. The remaining 11 plants re-burn fly ash. At three plants the fly ash is first separated in a mesh sieve or similar equipment and only the coarser fly ash is re-burnt. As the amount of bottom ash that surfaces in the wet ash-removal is relatively small

  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...

  3. 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... Miscellaneous § 109.555 Propulsion boilers. The master or person in charge and the engineer in charge shall ensure that— (a) Steam pressure does not exceed that allowed by the certificate of inspection; and...

  4. Technology of latent-heat recovery for boiler system; Boira ni okeru sennetsu kaishu gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    Moriyama, T. [Tokyo Gas Co. Ltd. (Japan)

    1996-08-01

    The boiler has reached the highest degree of completion among combustion equipment and is highly efficient. In order to enhance its efficiency further, it is ordinary to recover the retention heat of the combustion exhaust gas, but due to the problem of low temperature corrosion caused by the sulfur content in fuel resulted from a temperature drop of the exhaust gas, heat recovery has been done not sufficiently. In this article, an example is introduced to plan the betterment of efficiency by application of a latent heat recovering economizer to a sugar manufactory and a report is made on the energy saving effect by recovering the latent heat and a study on the quality of the material for the latent heat reclaimer. The above latent heat reclaimer is a system which takes advantage of the feature of the natural gas reportedly having no sulfur content, brings down the temperature at the outlet of a heat exchanger of the boiler exhaust gas to below the dew point, thereby recovers the condensed latent heat of the vapor in the exhaust gas and utilizes it for heating up the boiler feed water. In this example, the line of an already installed boiler has been partially modified and only a latent heat reclaimer has been installed newly. The increase of efficiency has been as high as 5.28%. 5 figs., 5 tabs.

  5. Single phase and two phase erosion corrosion in broilers of gas-cooled reactors

    International Nuclear Information System (INIS)

    Erosion-corrosion is a phenomenon causing metal wastage in a variety of locations in water and water-steam circuits throughout the power generation industry. Erosion-corrosion can occur in a number of regions of the once-through boiler designs used in the later Magnox and AGR type of gas cooled nuclear reactor. This paper will consider two cases of erosion-corrosion damage (single and two phase) in once through boilers of gas cooled reactors and will describe the solutions that have been developed. The single phase problem is associated with erosion-corrosion damage of mild steel downstream of a boiler inlet flow control orifice. With metal loss rates of up to 1 mm/year at 150 deg. C and pH in the range 9.0-9.4 it was found that 5 μg/kg oxygen was sufficient to reduce erosion-corrosion rates to less than 0.02 mm/year. A combined oxygen-ammonia-hydrazine feedwater regime was developed and validated to eliminate oxygen carryover and hence give protection from stress corrosion in the austenitic section of the AGR once through boiler whilst still providing erosion-corrosion control. Two phase erosion-corrosion tube failures have occurred in the evaporator of the mild steel once through boilers of the later Magnox reactors operating at pressures in the range 35-40 bar. Rig studies have shown that amines dosed in the feedwater can provide a significant reduction in metal loss rates and a tube lifetime assessment technique has been developed to predict potential tube failure profiles in a fully operational boiler. The solutions identified for both problems have been successfully implemented and the experience obtained following implementation including any problems or other benefits arising from the introduction of the new regimes will be presented. Methods for monitoring and evaluating the efficiency of the solutions have been developed and the results from these exercises will also be discussed. Consideration will also be given to the similarities in the metal loss

  6. Nickel-base alloys combat corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, D.C. [VDM Technologies Corp., Houston, TX (United States); Herda, W. [Krupp-VDM GmbH, Werdohl (Germany)

    1995-06-01

    The modern chemical process industry must increase production efficiency to remain competitive. Manufacturers typically meet this challenge by utilizing higher temperatures and pressures, and more-corrosive catalysts. At the same time, the industry has to solve the technical and commercial problems resulting from rigid environmental regulations. To overcome these obstacles, new alloys having higher levels of corrosion resistance have been developed. These materials are based on increased understanding of the physical metallurgy of nickel-base alloys, especially the role of alloying elements. Results of many studies have led to innovations in nickel-chromium-molybdenum alloys containing both high and low amounts of nickel. Higher molybdenum and chromium contents, together with nitrogen additions, have opened up an entirely new class of alloys having unique properties. In addition, a new chromium-base, fully wrought super stainless steel shows excellent promise in solving many corrosion problems. These newer alloys have the ability to combat uniform corrosion, localized corrosion, and stress-corrosion cracking in the harsh halogenic environment of the chemical process industry. This article briefly lists some of the major highlights and corrosion data on recent nickel-chromium-molybdenum and nickel-molybdenum alloys, and the development of a chromium-base, wrought super-austenitic alloy known as Nicrofer 3033 (Alloy 33). Some comparisons with existing alloys are presented, along with a few commercial applications.

  7. The comparison of corrosion resistance between Baosteel's alloy 690 tube and foreign alloy 690 tube

    International Nuclear Information System (INIS)

    Alloy 690 having excellent corrosion resistance is widely used for SG tubes. The intergranular corrosion and pitting corrosion resistance of Baosteel's alloy 690 tube, Country A alloy 690 tube and Country B alloy 690 tube have been analysed by comparison. It shows that: The intergranular corrosion of Baosteel's alloy 690 tube tested complied with ASTM G28 Standard could satisfy the technical requirement. However.some of Baosteel's alloy 690 tube in intergranular corrosion resistance had less performance than Country A. In addition, pitting corrosion tested with ASTM G48 Standard shown the Baosteel's alloy 690 tube better than Country B. (authors)

  8. Thermographic imaging of material loss in boiler water-wall tubing by application of scanning line source

    Science.gov (United States)

    Cramer, K. Elliott; Winfree, William P.

    2000-06-01

    Localized wall thinning due to corrosion in utility boiler water-wall tubing is a significant inspection concern for boiler operators. Historically, conventional ultrasonics has been used for inspection of these tubes. This technique has proven to be very manpower and time intensive. This has resulted in a 'spot check' approach to inspections, documenting thickness measurements over a relatively small percentage of the total boiler wall area. NASA Langley Research Center has developed a thermal NDE technique designed to image and quantitatively characterize the amount of material thinning present in steel 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 for large structures such as boiler water-walls. A theoretical basis for the technique will be presented which explains 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 applying this technology to actual water-wall tubing samples and in situ inspections will be presented.

  9. Combating corrosion in biomass and waste fired plant

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, Pamela [Vattenfall AB, Stockholm (Sweden). Research and Development; Hjoernhede, Anders [Vattenfall AB, Gothenburg (Sweden). Power Consultant

    2010-07-01

    Many biomass- or waste-fired plants have problems with high temperature corrosion especially if the steam temperature is greater than 500 C. An increase in the combustion of waste fuels means that an increasing number of boilers have had problems. Therefore, there is great interest in reducing the costs associated with high temperature corrosion and at the same time there exists a desire to improve the electrical efficiency of a plant by the use of higher steam temperatures. Assuming that the fuel is well-mixed and that there is good combustion control, there are in addition a number of other measures which can be used to reduce superheater corrosion in biomass and waste fired plants, and these are described in this paper. These include the use of fuel additives, specifically sulphur-containing ones; design aspects like placing superheaters in less corrosive positions in a boiler, using tube shielding, a wider pitch between the tubes; operational considerations such as more controlled soot-blowing and the use of better materials. (orig.)

  10. 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.

  11. A improved fuzzy analytic hierarchy process application in prevention high temperature corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Haiyu; Xiong, Xiaohe; Niu, Yanqing; Xu, Tongmo [Xi' an Jiaotong Univ. (China). School of Energy and Power Engineering; Tan, Houzhang [Xi' an Jiaotong Univ. (China). School of Energy and Power Engineering; Leeds Univ. (United Kingdom). CFD Centre/SPEME; Yao, Linzhi [Taiyuan Univ. of Technology (China); Ma, Lin [Leeds Univ. (United Kingdom). CFD Centre/SPEME

    2013-07-01

    The mechanism of formation of high temperature corrosion in large scale utility boilers is complex and involves numerous interrelated influencing factors. The fuzzy analytic hierarchy process (FAHP) has been employed in this chapter to make quantitative computations of the factors that influence the formation of the corrosion. When constructing the fuzzy judgment matrix, an affecting degree table of influencing factors was worked out first. Then the score of a pair-wise comparison was computed from a proposed expression r{sub ij} = x - y + 0.5. This improved method was applied to the analysis of the high temperature corrosion problem of a 215 MW coal-fired utility boiler, combining with in-site test data. The weights of the influencing factors were determined quantitatively and the main influencing factors were found out. Based on the calculated results, various adjustments to the combustion processes were made and, as a result, high temperature corrosion on the water wall tubes has been found largely reduced on the schedule shutdown of the boiler half year later. Moreover, a real-time high temperature corrosion detection technique can be developed based on the method reported in this chapter.

  12. Maintenance for blowing out industrial boiler under subtropical monsoon climate%亚热带季风气候环境下工业锅炉停炉防腐保养的建议

    Institute of Scientific and Technical Information of China (English)

    马铭潞; 王磊

    2016-01-01

    本文通过对锅炉内检常见的腐蚀案例进行分析,针对亚热带疾风气候环境下工业锅炉停炉保养难度大等问题提出了有效的解决方法,防止锅炉腐蚀,确保安全、经济运行。%This article presents the case study on corrosion in boiler to offer solutions in terms of difficulties in maintenance for industrial boiler under subtropical monsoon climate, which will ensure the economic and safe operation of the boiler.

  13. Coal Ash Corrosion Resistant Materials Testing

    Energy Technology Data Exchange (ETDEWEB)

    D. K. McDonald; P. L. Daniel; D. J. DeVault

    2003-08-31

    In April 1999, three identical superheater test sections were installed into the Niles Unit No.1 for the purpose of testing and ranking the coal ash corrosion resistance of candidate superheater alloys. The Niles boiler burns high sulfur coal (3% to 3.5%) that has a reasonably high alkali content, thus the constituents necessary for coal ash corrosion are present in the ash. The test sections were controlled to operate with an average surface metal temperature from approximately 1060 F to 1210 F which was well within the temperature range over which coal ash corrosion occurs. Thus, this combination of aggressive environment and high temperature was appropriate for testing the performance of candidate corrosion-resistant tube materials. Analyses of the deposit and scale confirmed that the aggressive alkali-iron-trisulfate constituent was present at the metal surface and active in tube metal wastage. The test sections were constructed so that the response of twelve different candidate tube and/or coating materials could be studied. The plan was to remove and evaluate one of the three test sections at time intervals of 1 year, 3 years, and 5 years. This would permit an assessment of performance of the candidate materials as a function of time. This report provides the results of the evaluation of Test Section C, including the samples that remained in the Test Section for the full exposure period as well as those that were removed early. The analysis of Test Section C followed much the same protocol that was employed in the assessment of Test Section A. Again, the focus was on determining and documenting the relative corrosion rates of the candidate materials. The detailed results of the investigation are included in this report as a series of twelve appendices. Each appendix is devoted to the performance of one of the candidate alloys. The table below summarizes metal loss rate for the worst case sample of each of the candidate materials for both Test Sections A and C

  14. Green Inhibitors for Corrosion Protection of Metals and Alloys: An Overview

    OpenAIRE

    B E Amitha Rani; Basu, Bharathi Bai J.

    2012-01-01

    Corrosion control of metals is of technical, economical, environmental, and aesthetical importance. The use of inhibitors is one of the best options of protecting metals and alloys against corrosion. The environmental toxicity of organic corrosion inhibitors has prompted the search for green corrosion inhibitors as they are biodegradable, do not contain heavy metals or other toxic compounds. As in addition to being environmentally friendly and ecologically acceptable, plant products are inexp...

  15. Coal-fired power plants and the causes of high temperature corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Oakey, J.E.; Simms, N.J. [British Coal Corporation, Coal Technology Development Div., Cheltenham, Glos (United Kingdom); Tomkings, A.B. [ERA Technology Ltd., Leatherhead, Surrey (United Kingdom)

    1996-12-01

    The heat exchangers in all types of coal-fired power plant operate in aggressive, high temperature environments where high temperature corrosion can severely limit their service lives. The extent of this corrosion is governed by the combined effects of the operating conditions of the heat exchanger and the presence of corrosive species released from the coal during operation. This paper reviews the coal-related factors, such as ash deposition, which influence the operating environments of heat exchangers in three types of coal-fired power plant - conventional pulverized coal boilers, fluidized bed boilers and coal gasification systems. The effects on the performance of the materials used for these heat exchangers are then compared. (au) 35 refs.

  16. CAUSE FOR LEAKAGE FROM 200 MW BOILER TUBE%锅炉管腐蚀泄漏原因分析

    Institute of Scientific and Technical Information of China (English)

    姜锡瑞; 罗兆红

    2001-01-01

    Presents the identification of cause for leakage from 200 MW boiler tube by testing for mechanical property and chemical composition, analysis of metallographical organism and corrosion products and testing for electrode potential and polarization curve of boiler tube material,and points out alkaline corrosion occurs during boiler operation and shutdown when oxygen dissolves into water and Fe3O4 Fe2O3 and corrosion products lead to condensation of alkali at high temperature.%通过对锅炉管材的机械性能、化学成分测定和对金相组织、腐蚀产物的分析及电极电位、极化曲线的测定,找出了锅炉管坑孔腐蚀原因,是由于在锅炉工作和停运时氧溶入使Fe3O4氧化成Fe2O3和在高温条件腐蚀产物下形成碱浓缩导致碱腐蚀.

  17. Status of coal ash corrosion resistant materials test program

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, D.K.; Meisenhelter, D.K.; Sikka, V.K.

    1999-07-01

    In November of 1998, Babcock and Wilcox (B and W) began development of a system to permit testing of several advanced tube materials at metal temperatures typical of advanced supercritical steam conditions of 1100 F and higher in a boiler exhibiting coal ash corrosive conditions. The U.S. Department of Energy (DOE), the Ohio Coal Development Office (OCDO), B and W, and First Energy's Ohio Edison jointly fund the project. CONSOL Energy Company is also participating as an advisor. Several materials producers including Oak Ridge National Laboratory (ORNL) contributed advanced materials to the project. The coal-ash corrosion resistant materials test program will provide full scale, in-situ testing of recently developed boiler superheater and reheater tube materials. These newer materials may be capable of operating at higher steam temperatures while resisting external/fire-side corrosion. For high sulfur coal applications, this is a key issue for advanced cycle pulverized coal-fired plants. Fireside corrosion is also a critical issue for many existing plants. Previous testing of high temperature materials in the United States has been based primarily on using laboratory test coupons. The test coupons did not operate at conditions representative of a high sulfur coal-fired boiler. Testing outside of the United States has been with low sulfur coal or natural gas firing and has not addressed corrosion issues. This test program takes place in an actual operating boiler and is expected to confirm the performance of these materials with high sulfur coal. The system consists of three identical sections, each containing multiple pieces of twelve different materials. They are cooled by reheater steam, and are located just above the furnace exit in Ohio Edison's Niles Unit No.1, a 110 MWe unit firing high sulfur Ohio coal. After one year of operation, the first section will be removed for thorough metallurgical evaluation. The second and third sections will operate for

  18. Method and algorithm of ranking boiler plants at block electric power stations by the criterion of operation reliability and profitability

    Science.gov (United States)

    Farhadzadeh, E. M.; Muradaliyev, A. Z.; Farzaliyev, Y. Z.

    2015-10-01

    A method and an algorithm of ranking of boiler installations based on their technical and economic indicators are proposed. One of the basic conditions for ranking is the independence of technical and economic indicators. The assessment of their interrelation was carried out with respect to the correlation rate. The analysis of calculation data has shown that the interrelation stability with respect to the value and sign persists only for those indicators that have an evident relationship between each other. One of the calculation steps is the normalization of quantitative estimates of technical and economic indicators, which makes it possible to eliminate differences in dimensions and indicator units. The analysis of the known methods of normalization has allowed one to recommend the relative deviation from the average value as a normalized value and to use the arithmetic mean of the normalized values of independent indicators of each boiler installation as an integrated index of performance reliability and profitability. The fundamental differences from the existing approach to assess the "weak components" of a boiler installation and the quality of monitoring of its operating regimes are that the given approach takes into account the reliability and profitability of the operation of all other analogous boiler installations of an electric power station; it also implements competing elements with respect to the quality of control among the operating personnel of separate boiler installations and is aimed at encouraging an increased quality of maintenance and repairs.

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

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

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

  20. 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...

  1. 49 CFR 230.30 - Lap-joint seam boilers.

    Science.gov (United States)

    2010-10-01

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

  2. 46 CFR 61.05-15 - Boiler mountings and attachments.

    Science.gov (United States)

    2010-10-01

    ... gauge for a boiler or a main steam line may be examined and checked for accuracy by the marine inspector... 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....

  3. Corrosion experience with fuel at LVR-15 reactor

    International Nuclear Information System (INIS)

    There are three research reactors in Czech Republic, LVR-15 at NRI Rez and VR-1 at Technical University Prague in operation and SKODA reactor in decommissioning. All reactors use the same IRT-2M (3M) type fuel manufactured in Russia. At present 36% enrichment is used. Corrosion experience with used fuel at all three reactors is described. The fuel was exposed by water environment in reactor during operation and following in pool during storage. Investigation of fuel surface revealed pitting corrosion on surface which did not enable next utilization of fuel in operation. Description of corrosion pits and possible influence of water chemistry and mechanical treatment are discussed. Relation between water pool conductivity and corrosion damage is probable mechanism of pitting corrosion. This phenomena is also influenced by mechanical removal of corrosion protective layer by mechanical treatment. (author)

  4. Characterization of Encapsulated Corrosion Inhibitors for Environmentally Friendly Smart Coatings

    Science.gov (United States)

    Pearman, Benjamin Pieter; Li, Wenyan; Buhrow, Jerry; Zhang, Xuejun; Surma, Jan; Fitzpatrick, Lilly; Montgomery, Eliza; Calle, Luz Marina

    2014-01-01

    Research efforts are under way to replace current corrosion inhibitors with more environmentally friendly alternatives. However, problems with corrosion inhibition efficiency, coating compatibility and solubility have hindered the use of many of these materials as simple pigment additives.This paper will present technical details on how the Corrosion Technology Lab at NASAs Kennedy Space Center (KSC) has addressed these issues by encapsulating environmentally friendly inhibitors into organic and inorganic microparticles and microcapsules. The synthetic process for polymer particles was characterized and post-synthesis analysis was performed to determine the interactions between the inhibitors and the encapsulation material. The pH-controlled release of inhibitors from various particle formulations in aqueous base was monitored and compared to both electrochemical and salt immersion accelerated corrosion experiment. Furthermore, synergistic corrosion inhibition effects observed during the corrosion testing of several inhibitor combinations will be presented.

  5. Electrical design requirements for electrode boilers for nuclear plants

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

    Levasseur, Armand

    2014-04-30

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

  7. Environmentally Friendly Coating Technology for Autonomous Corrosion Control

    Science.gov (United States)

    Calle, Luz M.; Li, Wenyan; Buhrow, Jerry W.; Johnsey, Marissa N.; Jolley, Scott T.; Pearman, Benjamin P.; Zhang, Xuejun; Fitzpatrick, Lilliana; Gillis, Mathew; Blanton, Michael; Hanna, Joshua S.; Rawlins, James W.

    2016-01-01

    This work concerns the development of environmentally friendly encapsulation technology, specifically designed to incorporate corrosion indicators, inhibitors, and self-healing agents into a coating, in such a way that the delivery of the indicators and inhibitors is triggered by the corrosion process, and the delivery of self-healing agents is triggered by mechanical damage to the coating. Encapsulation of the active corrosion control ingredients allows the incorporation of desired autonomous corrosion control functions such as: early corrosion detection, hidden corrosion detection, corrosion inhibition, and self-healing of mechanical damage into a coating. The technology offers the versatility needed to include one or several corrosion control functions into the same coating.The development of the encapsulation technology has progressed from the initial proof-of-concept work, in which a corrosion indicator was encapsulated into an oil-core (hydrophobic) microcapsule and shown to be delivered autonomously, under simulated corrosion conditions, to a sophisticated portfolio of micro carriers (organic, inorganic, and hybrid) that can be used to deliver a wide range of active corrosion ingredients at a rate that can be adjusted to offer immediate as well as long-term corrosion control. The micro carriers have been incorporated into different coating formulas to test and optimize the autonomous corrosion detection, inhibition, and self-healing functions of the coatings. This paper provides an overview of progress made to date and highlights recent technical developments, such as improved corrosion detection sensitivity, inhibitor test results in various types of coatings, and highly effective self-healing coatings based on green chemistry.

  8. Power for the industrial age: a brief history of boilers

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, S.E.

    1996-02-01

    Boilers were first designed in Greece during the Hellenistic period by Hero, but they were regarded purely as a novelty and no industrial application was found for these toys until the seventeenth century when mining engineers used them for steam-powered pumps. By the end of the 17th century the early shell boilers were replaced by tube boilers, the direct ancestors of the modern boiler. Among the best known of the early boiler manufacturers was Babcock and Wilcox, and they supplied boilers to one of the first electric power plants. In the early 20th century superheaters, economizers, stokers and pulverizers were added to the design of the utility boiler. Fusion-welded boiler drums added to safety. More recently environmental concerns have initiated a new generation of boilers, such as the pressurised fluidised bed combustion boilers and their advanced versions. 5 refs., 3 figs.

  9. Boiler efficiency methodology for solar heat applications

    Science.gov (United States)

    Maples, D.; Conwell, J. C.; Pacheco, J. E.

    1992-08-01

    This report contains a summary of boiler efficiency measurements which can be applied to evaluate the performance of steam-generating boilers via both the direct and indirect methods. This methodology was written to assist industries in calculating the boiler efficiency for determining the applicability and value of thermal industrial heat, as part of the efforts of the Solar Thermal Design Assistance Center (STDAC) funded by Sandia National Laboratories. Tables of combustion efficiencies are enclosed as functions of stack temperatures and the amount of carbon dioxide and carbon monoxide in the gas stream.

  10. Chemical cleaning of UK AGR boilers

    International Nuclear Information System (INIS)

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

  11. Countermeasures to corrosion on water walls; Aatgaerder mot eldstadskorrosion paa panntuber

    Energy Technology Data Exchange (ETDEWEB)

    Storesund, Jan; Sund, Goeran; Pettersson, Rachel; Nordling, Magnus; Hoegberg, Jan

    2007-12-15

    Corrosion of water walls is becoming a problem for an increasing number of boilers. Wider use of biomass and waste for fuel, as well as requirements of reduced NO{sub x} emissions, makes it much more difficult to avoid combustion in a reducing atmosphere adjacent to the water walls. This has increased the need for corrosion protection in many existing boilers. In addition, biomass and waste fuelled plants currently being planned or built require well-functioning water wall protection from the start. The traditional water wall materials - ferritic low alloyed steels - are not easy to replace because of their outstanding heat transfer properties, ability to form a protective oxide layer on the inside of the tubes and low thermal expansion. For this reason, corrosion protection generally involves the use of some kind of coating on the tubes. In this report, the state-of-the-art regarding water wall corrosion protection is described in a literature survey. Methods covered are the use of refractories, overlay weld cladding, composite tubes and thermal spraying. The interest for overlay welding has increased recently since it can offer similar corrosion protection to composite tubes at a significantly reduced cost. Test panels have been exposed and monitored in different boilers. Six weld overlay materials were tested: the well-proven Alloy 625, a modified Alloy 625 in which niobium has been replaced by tungsten, Alloy 59, Alloy 22, a cheaper nickel base alloy 650 which contains some iron and a 310 grade stainless steel. A total of six panels were exposed in the most vulnerable positions in three different boilers. These included waste and biomass combustion as well as different steam data, sizes and types of boilers. Two further facilities, in which the test materials Alloy 625 and Sanicro 28 had already been installed, were also included in the investigation. The duration of service exposure was one operating season. The weld cladding was measured with a thickness

  12. 某厂蒸汽锅炉水处理研究%Research on the treatment of boiler water of a factory

    Institute of Scientific and Technical Information of China (English)

    郭锋

    2015-01-01

    某厂蒸汽锅炉工作压力1.25 MPa,蒸汽量19 t/h,除氧器不开。锅炉为企业职工食堂、洗衣间提供蒸汽,冬天负责供暖。通过添加锅炉除氧剂、阻垢剂、冷凝水缓蚀剂,有效地控制了水冷壁的腐蚀、结垢和蒸汽管道与冷凝回水管道的腐蚀。药剂现场使用1a多,锅炉运行良好,顺利通过年检。%The operation situation of the steam boiler of a factory is as follows:its pressure is 1.25 MPa and the amount of steam is 19 t/h,but the boiler deaerator is not open. The boiler is used for providing steam for staff canteen laundry and heating in winter. By adding boiler deoxidizing agent ,scale inhibitor and condensed water corrosion in-hibitor,the corrosion on water-cooled-wall,the corrosion on the pipes of scaling and steam,and on the return pipes of condensate are effectively controlled. The chemicals in use for more than a year have been running well and passed the annual inspection successfully.

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

    International Nuclear Information System (INIS)

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

  14. Modelling of Corrosion Cracks

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    Modelling of corrosion cracking of reinforced concrete structures is complicated as a great number of uncertain factors are involved. To get a reliable modelling a physical and mechanical understanding of the process behind corrosion in needed.......Modelling of corrosion cracking of reinforced concrete structures is complicated as a great number of uncertain factors are involved. To get a reliable modelling a physical and mechanical understanding of the process behind corrosion in needed....

  15. Fireside corrosion testing of candidate superheater tube alloys, coatings, and claddings -- Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Blough, J.L.; Seitz, W.W. [Foster Wheeler Development Corp., Livingston, NJ (United States)

    1997-12-01

    In Phase 1 a variety of developmental and commercial tubing alloys and claddings were exposed to laboratory fireside corrosion testing simulating a superheater or reheater in a coal-fired boiler. Phase 2 (in situ testing) has exposed samples of 347 RA-85H, HR3C, 253MA, Fe{sub 3}Al + 5Cr, 310 Ta modified, NF 709, 690 clad, and 671 clad for approximately 4,000, 12,000, and 16,000 hours to the actual operating conditions of a 250-MW coal-fired boiler. The samples were assembled on an air-cooled, retractable corrosion probe, the probe was installed in the reheater activity of the boiler and controlled to the operating metal temperatures of an existing and advanced-cycle coal-fired boiler. The results will be presented for the preliminary metallurgical examination of the corrosion probe samples after 16,000 hours of exposure. Continued metallurgical and interpretive analysis is still on going.

  16. Management of Reinforcement Corrosion

    DEFF Research Database (Denmark)

    Küter, André; Geiker, Mette Rica; Møller, Per

    Reinforcement corrosion is the most important cause for deterioration of reinforced concrete structures, both with regard to costs and consequences. Thermodynamically consistent descriptions of corrosion mechanisms are expected to allow the development of innovative concepts for the management...... of reinforcement corrosion....

  17. Erosion-corrosion

    International Nuclear Information System (INIS)

    A literature study on erosion-corrosion of pipings in the nuclear industry was performed. Occurred incidents are reviewed, and the mechanism driving the erosion-corrosion is described. Factors that influence the effect in negative or positive direction are treated, as well as programs for control and inspection. Finally, examples of failures from databases on erosion-corrosion are given in an attachment

  18. Management of Reinforcement Corrosion

    DEFF Research Database (Denmark)

    Küter, André; Geiker, Mette Rica; Møller, Per

    Reinforcement corrosion is the most important cause for deterioration of reinforced concrete structures, both with regard to costs and consequences. Thermodynamically consistent descriptions of corrosion mechanisms are expected to allow the development of innovative concepts for the management of...... reinforcement corrosion....

  19. Additive for reducing operational problems in waste fired grate boilers; Additiv foer att minska driftproblem vid rostfoerbraenning av avfall

    Energy Technology Data Exchange (ETDEWEB)

    Gyllenhammar, Marianne; Herstad Svaerd, Solvie; Davidsson, Kent; Hermansson, Sven; Liske, Jesper; Larsson, Erik; Jonsson, Torbjoern; Zhao, Dongmei

    2013-09-01

    The combustion of waste implies a risk for deposits and corrosion in different parts of the combustion facility. In recent years, research and tests have been performed in order to find ways to mitigate these problems in waste-fired plants. Most waste-fired plants in Sweden are grates whereas most of the research has been carried out in fluidized bed plants. The purpose of this project is to examine whether co-firing of sewage sludge and waste can reduce deposition and corrosion also in grate-fired boilers as has been shown in fludised beds. The objective is to determine the deposit growth and its composition as well as describing the initial corrosion attack. Representing sulphur-rich waste, elementary sulphur is also added to the waste and thereby compared with sludge as an additive. The target groups for this project are plant owners, researchers, consultants and authorities. Tests were performed in a 15 MWth waste-fired boiler with moving grate at Gaerstadverket, Tekniska Verken (Linkoeping). The boiler produces saturated steam of 17 bars and 207 deg C, and the normal fuel mixture contains of household and industry waste. The results show that co-firing with as heigh as 20 weight-% SLF (25 energy-%) was possible from an operational point of view, but the deposit rate increased especially at the two warmest positions. Generally the deposit rate was highest in the position closest to the boiler and decreased further downstream. During the tests a lot higher amount of SLF than normal was used (recommended mix is 5-10 % of SLF) this to be able to see effects of the different measures. Up to 23 weight-% of the rather moist sewage sludge was possible to fire when co-firing waste and SLF, without addition of oil. By adding sludge the deposit rate decreased but the increase upon adding SLF to ordinary waste was not totally eliminated. In the tests 'Avfall and SLF' the deposits were rich in chlorine. High concentrations of metal chlorides were found in the

  20. 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....

  1. Corrosion in waste incineration facilities; Korrosion i avfallsfoerbraenningsanlaeggningar

    Energy Technology Data Exchange (ETDEWEB)

    Staalenheim, Annika; Henderson, Pamela

    2004-11-01

    Waste is a heterogeneous fuel, often with high levels of chlorine, alkali and heavy metals. This leads to much more severe corrosion problems than combustion of fossil fuels. The corrosion rates of the materials used can be extremely high. Materials used for heat transferring parts are usually carbon steel or low alloyed steel. These are significantly cheaper than other steels. Austenitic stainless steel is also used, but is often avoided due to its sensitivity to stress corrosion cracking. More advanced materials, such as nickel base alloys, can be used in extremely aggressive environments. Since these materials are expensive and do not always have sufficient mechanical properties, they are often used as coatings on carbon steel tubes or as composite tubes. A new method, which shows good results at the first tests in plants, is electroplating with nickel. Plastic materials can be used in low temperature parts if the temperature does not exceed 150 deg C. A glass fibre inforced material is probably the best choice. The parts of the furnace that are most prone to corrosion are waterwalls where the refractory coating is lost, has not been applied to a sufficient height in the boiler or is not used at all. Failures of superheaters often occur in areas near soot blowers or on the tubes exposed to the highest flue gas temperatures. Few cases of low temperature corrosion are reported in the literature, possibly because these problems are unusual or because low temperature corrosion rarely causes costly and dramatic failures. Waterwall tubes should be made of carbon steel, because of the price and to minimise the risk for stress corrosion cracking. Usually the tubes must be covered with a more corrosion resistant material to withstand the environment in the boiler. Metal coatings can be used in less demanding environments. Refractory is probably the best protection for waterwalls from severe erosion. Surfaces in extremely corrosive areas, e.g. the fuel feed area, should

  2. Ecological boiler modernization, feasible energy solutions

    International Nuclear Information System (INIS)

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

  3. 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.

  4. 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. PMID:22049674

  5. A New Agro/Forestry Residues Co-Firing Model in a Large Pulverized Coal Furnace: Technical and Economic Assessments

    Directory of Open Access Journals (Sweden)

    Shien Hui

    2013-08-01

    Full Text Available Based on the existing biomass co-firing technologies and the known innate drawbacks of dedicated biomass firing, including slagging, corrosion and the dependence on fuel, a new model of agro/forestry residue pellets/shreds and coal co-fired in a large Pulverized Coal (PC furnace was proposed, and the corresponding technical and economic assessments were performed by co-firing testing in a 300 MW PC furnace and discounted cash flow technique. The developed model is more dependent on injection co-firing and combined with co-milling co-firing. Co-firing not only reduces CO2 emission, but also does not significantly affect the fly ash use in cement industry, construction industry and agriculture. Moreover, economic assessments show that in comparison with dedicated firing in grate furnace, agro/forestry residues and coal co-firing in a large PC furnace is highly economic. Otherwise, when the co-firing ratio was below 5 wt%, the boiler co-firing efficiency was 0.05%–0.31% higher than that of dedicated PC combustion, and boiler efficiencies were about 0.2% higher with agro/forestry residues co-firing in the bottom and top burner systems than that in a middle burner system.

  6. Economical Comporison PC and CFB Boilers for Retrofit and New Power Plants in Russia

    Science.gov (United States)

    Ryabov, G. A.

    According to the investment programmes of Russian electricity generating companies increased attention is paid to reconstruction and building new coal TPP. The typical projects are 225, 330 and 600 MW blocks for combustion of different domestic coals. VTI had made technical and economical comparison of CFB and PC boilers for existing and perspective (European) standards of particles, NOx and SOx emissions, according to the data of the prehminary designs and investments in new power plants of 225 and 330 MW. As the basis for technical and economical evaluations was used comparison data of metal-capacity of PC and boilers, emissions-control systems and material-handling systems, with paying attention to the exact suggestions of the boiler producers. The results of the comparisons (capital costs and O&M costs) are discussed in the paper. The most perspective fuels for combustion in CFB boilers are: anthracite culm, coals of the Pechora area, lean coals of Kuznetsk, brown coals of near Moscow, brown coals of Urals and Far East, and also the wastes of coal preparations, peat, shells and biomass. A good composition could be made from Kuznetsk coals and coals of Pechora area. Brown coals are combusted very good in suitable conditions for firing biomass and peat. Also allowed co-combustion with the wastes of coal preparations for the low reactivity fuels such as anthracite culm and lean coals. The diversification of the fuel supply is an essential advantage of CFB boilers. The CFB boiler installations are rather new for the conditions of Russian Federation. For decreasing the technical risks, first installations should be supplied by engineering or license of leading foreign companies with rather big part of their participation. One of important tasks is development of the typical projects, which would allow decreasing not only capital costs, but also decrease time of project realization. The project of the new Block #9 330MW with OTU boiler of Novocherkassk TPP is the

  7. Effect of a condensation utilizer on the operation of steam and hot-water gas-fired boilers

    Science.gov (United States)

    Ionkin, I. L.; Ragutkin, A. V.; Roslyakov, P. V.; Supranov, V. M.; Zaichenko, M. N.; Luning, B.

    2015-05-01

    Various designs for condensation utilizers of the low-grade heat of furnace gases that are constructed based on an open-type heat exchanger are considered. Computational investigations are carried out for the effect of the condensation utilizer with tempering and moistening of air on the operation of steam and hot-water boilers burning natural gas. The investigations are performed based on the predeveloped adequate calculating models of the steam and hot-water boilers in a Boiler Designer program complex. Investigation results for TGM-96B and PTVM-120 boilers are given. The enhancement of the operation efficiency of the condensation utilizer can be attained using a design with tempering and moistening of air supplied to combustion that results in an insignificant increase in the temperature of waste gases. This has no effect on the total operation efficiency of the boiler and the condenser unit, because additional losses with waste gases are compensated owing to the operation of the last. The tempering and moistening of air provide a substantial decrease in the temperature in the zone of active combustion and shortening the nitrogen oxide emission. The computational investigations show that the premoistening of air supplied to combustion makes the technical and economic efficiency of boilers operating with the Condensation Utilizer no worse.

  8. Effect of hot corrosion on the creep properties of types 321 and 347 stainless steels

    Science.gov (United States)

    González-Rodríguez, J. G.; Luna-Ramírez, A.; Martínez-Villafañe, A.

    1999-02-01

    Problems caused by hot corrosion and creep damage on superheater and reheater tubes of power plants using heavy oil as fuel inhibit the continuous service of the boilers and shorten their design lives. The acceleration of hot corrosion attack of boilers is caused by the presence of fuel ash deposits containing V, Na, and S, in the form of Na2SO4 and V2O5, which form low melting point phases. In addition to this, the tubes are exposed to the action of both high stresses and high temperatures, producing a continuous plastic deformation of the tube walls called creep damage. Creep rupture tests were carried out in the temperature range 620 to 670 °C in static air in the presence of corrosive environments using 321H and 347H type stainless steels used in superheater and reheater tubes under hot corrosion and creep environments. The corrosive environment includes synthetic Na2SO4, V2O5, and the mixture 80% V2O5-20%Na2SO4. Also, the role of the different elements present in the environments on corrosion was investigated using electronic microscopy and x-ray diffraction techniques.

  9. Hot Corrosion of Inconel 625 Overlay Weld Cladding in Smelting Off-Gas Environment

    Science.gov (United States)

    Mohammadi Zahrani, E.; Alfantazi, A. M.

    2013-10-01

    Degradation mechanisms and hot corrosion behavior of weld overlay alloy 625 were studied. Phase structure, morphology, thermal behavior, and chemical composition of deposited salt mixture on the weld overlay were characterized utilizing XRD, SEM/EDX, DTA, and ICP/OES, respectively. Dilution level of Fe in the weldment, dendritic structure, and degradation mechanisms of the weld were investigated. A molten phase formed on the weld layer at the operating temperature range of the boiler, which led to the hot corrosion attack in the water wall and the ultimate failure. Open circuit potential and weight-loss measurements and potentiodynamic polarization were carried out to study the hot corrosion behavior of the weld in the simulated molten salt medium at 873 K, 973 K, and 1073 K (600 °C, 700 °C, and 800 °C). Internal oxidation and sulfidation plus pitting corrosion were identified as the main hot corrosion mechanisms in the weld and boiler tubes. The presence of a significant amount of Fe made the dendritic structure of the weld susceptible to preferential corrosion. Preferentially corroded (Mo, Nb)-depleted dendrite cores acted as potential sites for crack initiation from the surface layer. The penetration of the molten phase into the cracks accelerated the cracks' propagation mainly through the dendrite cores and further crack branching/widening.

  10. Aqueous Corrosion Rates for Waste Package Materials

    International Nuclear Information System (INIS)

    The purpose of this analysis, as directed by ''Technical Work Plan for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]), is to compile applicable corrosion data from the literature (journal articles, engineering documents, materials handbooks, or standards, and national laboratory reports), evaluate the quality of these data, and use these to perform statistical analyses and distributions for aqueous corrosion rates of waste package materials. The purpose of this report is not to describe the performance of engineered barriers for the TSPA-LA. Instead, the analysis provides simple statistics on aqueous corrosion rates of steels and alloys. These rates are limited by various aqueous parameters such as temperature (up to 100 C), water type (i.e., fresh versus saline), and pH. Corrosion data of materials at pH extremes (below 4 and above 9) are not included in this analysis, as materials commonly display different corrosion behaviors under these conditions. The exception is highly corrosion-resistant materials (Inconel Alloys) for which rate data from corrosion tests at a pH of approximately 3 were included. The waste package materials investigated are those from the long and short 5-DHLW waste packages, 2-MCO/2-DHLW waste package, and the 21-PWR commercial waste package. This analysis also contains rate data for some of the materials present inside the fuel canisters for the following fuel types: U-Mo (Fermi U-10%Mo), MOX (FFTF), Thorium Carbide and Th/U Carbide (Fort Saint Vrain [FSVR]), Th/U Oxide (Shippingport LWBR), U-metal (N Reactor), Intact U-Oxide (Shippingport PWR, Commercial), aluminum-based, and U-Zr-H (TRIGA). Analysis of corrosion rates for Alloy 22, spent nuclear fuel, defense high level waste (DHLW) glass, and Titanium Grade 7 can be found in other analysis or model reports

  11. Aqueous Corrosion Rates for Waste Package Materials

    Energy Technology Data Exchange (ETDEWEB)

    S. Arthur

    2004-10-08

    The purpose of this analysis, as directed by ''Technical Work Plan for: Regulatory Integration Modeling and Analysis of the Waste Form and Waste Package'' (BSC 2004 [DIRS 171583]), is to compile applicable corrosion data from the literature (journal articles, engineering documents, materials handbooks, or standards, and national laboratory reports), evaluate the quality of these data, and use these to perform statistical analyses and distributions for aqueous corrosion rates of waste package materials. The purpose of this report is not to describe the performance of engineered barriers for the TSPA-LA. Instead, the analysis provides simple statistics on aqueous corrosion rates of steels and alloys. These rates are limited by various aqueous parameters such as temperature (up to 100 C), water type (i.e., fresh versus saline), and pH. Corrosion data of materials at pH extremes (below 4 and above 9) are not included in this analysis, as materials commonly display different corrosion behaviors under these conditions. The exception is highly corrosion-resistant materials (Inconel Alloys) for which rate data from corrosion tests at a pH of approximately 3 were included. The waste package materials investigated are those from the long and short 5-DHLW waste packages, 2-MCO/2-DHLW waste package, and the 21-PWR commercial waste package. This analysis also contains rate data for some of the materials present inside the fuel canisters for the following fuel types: U-Mo (Fermi U-10%Mo), MOX (FFTF), Thorium Carbide and Th/U Carbide (Fort Saint Vrain [FSVR]), Th/U Oxide (Shippingport LWBR), U-metal (N Reactor), Intact U-Oxide (Shippingport PWR, Commercial), aluminum-based, and U-Zr-H (TRIGA). Analysis of corrosion rates for Alloy 22, spent nuclear fuel, defense high level waste (DHLW) glass, and Titanium Grade 7 can be found in other analysis or model reports.

  12. High Temperature Corrosion of Water Wall Materials T23 and T24 in Simulated Furnace Atmospheres

    Institute of Scientific and Technical Information of China (English)

    赵钦新; 张知翔; 成丁南; 王云刚; 邓翔

    2012-01-01

    Candidate materials for water wall of supercritical and ultra-supercritical utility boilers,T23 and T24,were chosen as the experimental samples and exposed to oxidizing atmosphere,reducing atmosphere and oxidizing/reducing alternating atmosphere separately.The corrosion temperature was 450-550?C.The effects of oxygen con-tent and temperature on the corrosion in reducing atmosphere and alternating atmosphere were investigated.The scanning electron microscope(SEM) and energy dispersive spectrometer(EDS) were used to examine the corroded samples.The results show that the corrosion kinetics of T23 and T24 can be described by the double logarithmic equation and parabolic equation respectively.To describe the corrosion of materials accurately it is not sufficient to analyze the macro-mass gain and the macro-thickness of the corroded layer only,but the EDS should be applied to examine the migration depth of corrosive elements O and S.It is revealed that the corrosion becomes more severe when H2S is present in the corrosive gas.S is more active than O,and Cr can reduce the migration of oxygen but not S.The combination corrosion of S and O and pure [S] has a stronger corrodibility than pure H2S.T24 suffers the most severe corrosion at oxygen content of 0.8%.Corrosion is aggravated when the corrosion temperature is above 450 ℃ in the alternating atmosphere.T23 has better corrosion resistance than T24 and W contributes a lot to the corrosion resistance of T23.

  13. Countermeasures to corrosion on water walls. Part 2; Aatgaerder mot eldstadskorrosion paa panntuber. Etapp 2

    Energy Technology Data Exchange (ETDEWEB)

    Storesund, Jan; Elger, Ragna; Nordling, Magnus; Viklund, Peter

    2011-01-15

    Background: The problems with water wall corrosion have been accelerating over the last years. There are a number of reasons for this. Originally mild steels were successfully used in power plant water walls. The magnetite layer that forms at the fire side of the tubes when the boiler is taken into operation protected from corrosion attack. The fuels at that time (oil, coal, gas) were not able to break down the magnetite by corrosion. In addition, there were no restrictions for pollutions and for the combustion itself that could contribute to corrosion attack. The usage of fossil fuels has decreased substantially over the last 25 years, not least by environmental reasons. As a replacement a number of different kinds of bio mass fuels are used. These are typically more or less corrosive and the magnetite layers are attacked. The corrosion is often supported by reducing conditions as a result of the restrictions of the NO{sub x}-pollution. Also the waste fuelled boilers have huge corrosion problems. This has been the case for the last 25 years but nowadays the number of such plants is so much higher and the service data have been turned up. Corrosion protection of the water wall tubes started to be successful in the beginning of the seventies by the introduction of the composite tube. Such tubes are fabricated by mild steel or a low alloy core and corrosion resistant austenite steel or nickel base as an about 2 mm thick corrosion protective coating. Weld cladding of the water wall tubes was introduced in the 1980's as a significantly cheaper alternative to the composite tubes. Thermal spraying and refractory protection are other methods. These corrosion protection methods have not always been effective. For example, depending on incorrect materials selection, incorrect performance and incorrect method selection for the current corrosion or erosion attack. Therefore, there is a need for increased knowledge of which protection method and material that will work

  14. Fireside corrosion testing of candidate superheater tube alloys, coatings, and claddings - Phase II

    Energy Technology Data Exchange (ETDEWEB)

    Blough, J.L.; Krawchuk, M.T.; Van Weele, S.F. [Foster Wheeler Development Corp., Livingston, NJ (United States)

    1995-08-01

    A number of developmental and commercial tubing alloys and claddings have previously been exposed in Phase I to laboratory fireside corrosion testing simulating a superheater or reheater in a coal-fired boiler. This program is exposing samples of TP 347, RA-85H, HR-3C, 253MA, Fe{sub 3}Al + 5Cr, 310 modified, NF-709, 690 clad, and 671 clad, which showed good corrosion resistance from Phase 1, to the actual operating conditions of a 250-MW, coal-fired boiler. The samples were installed on air-cooled, retractable corrosion probes, installed in the reheater cavity, and are being controlled to the operating metal temperatures of an existing and advanced-cycle coal-fired boiler. The exposure will continue for 4000, 12,000, and 16,000 hours of operation. After the three exposure times, the samples will be metallurgically examined to determine the wastage rates and mode of attack. The probes were commissioned November 16, 1994. The temperatures are being recorded every 15 minutes, and the weighted average temperature calculated for each sample. Each of the alloys is being exposed to a temperature in each of two temperature bands-1150 to 1260{degrees}F and 1260 to 1325{degrees}F. After 2000 hours of exposure, one of the corrosion probes was cleaned and the wall thicknesses were ultrasonically measured. The alloy performance from the field probes will be discussed.

  15. Towards Corrosion Detection System

    Directory of Open Access Journals (Sweden)

    B.B.Zaidan

    2010-05-01

    Full Text Available Corrosion is a natural process that seeks to reduce the binding energy in metals. The end result of corrosion involves a metal atom being oxidized. Surface corrosion on aluminum aircraft skins, near joints and around fasteners, is often an indicator of buried structural corrosion and cracking In this paper we proposed a new method on which we are moving towards designing a method to detect the corrosion within the metals, the new method has defined texture analysis as the main method for this approach, the proposed enhancement shows less false positive and less false negative. The main functions used in this approach beside texture analysis are Edge detection, structure element and image dilation. The new approach has designed to detect a part of the image that has been affected by the corrosion, the tested images has showed a good result lying on detecting the corrosion part from the image.

  16. Resistance of Coatings for Boiler Components of Waste-to-Energy Plants to Salt Melts Containing Copper Compounds

    Science.gov (United States)

    Galetz, Mathias Christian; Bauer, Johannes Thomas; Schütze, Michael; Noguchi, Manabu; Cho, Hiromitsu

    2013-06-01

    The accelerating effect of heavy metal compounds on the corrosive attack of boiler components like superheaters poses a severe problem in modern waste-to-energy plants (WTPs). Coatings are a possible solution to protect cheap, low alloyed steel substrates from heavy metal chloride and sulfate salts, which have a relatively low melting point. These salts dissolve many alloys, and therefore often are the limiting factor as far as the lifetime of superheater tubes is concerned. In this work the corrosion performance under artificial salt deposits of different coatings, manufactured by overlay welding, thermal spraying of self-fluxing as well as conventional systems was investigated. The results of our studies clearly demonstrate the importance of alloying elements such as molybdenum or silicon. Additionally, the coatings have to be dense and of a certain thickness in order to resist the corrosive attack under these severe conditions.

  17. METHANE de-NOX for Utility PC Boilers

    Energy Technology Data Exchange (ETDEWEB)

    Bruce Bryan; Serguei Nester; Joseph Rabovitser; Stan Wohadlo

    2005-09-30

    The overall project objective is the development and validation of an innovative combustion system, based on a novel coal preheating concept prior to combustion, that can reduce NO{sub x} emissions to 0.15 lb/million Btu or less on utility pulverized coal (PC) boilers. This NO{sub x} reduction should be achieved without loss of boiler efficiency or operating stability, and at more than 25% lower levelized cost than state-of-the-art SCR technology. A further objective is to ready technology for full-scale commercial deployment to meet the market demand for NO{sub x} reduction technologies. Over half of the electric power generated in the U.S. is produced by coal combustion, and more than 80% of these units utilize PC combustion technology. Conventional measures for NOx reduction in PC combustion processes rely on combustion and post-combustion modifications. A variety of combustion-based NO{sub x} reduction technologies are in use today, including low-NO{sub x} burners (LNBs), flue gas recirculation (FGR), air staging, and natural gas or other fuel reburning. Selective non-catalytic reduction (SNCR) and selective catalytic reduction (SCR) are post-combustion techniques. NO{sub x} reduction effectiveness from these technologies ranges from 30 to 60% and up to 90-93% for SCR. Typically, older wall-fired PC burner units produce NO{sub x} emissions in the range of 0.8-1.6 lb/million Btu. Low-NO{sub x} burner systems, using combinations of fuel staging within the burner and air staging by introduction of overfire air in the boiler, can reduce NO{sub x} emissions by 50-60%. This approach alone is not sufficient to meet the desired 0.15 lb/million Btu NO{sub x} standard with a range of coals and boiler loads. Furthermore, the heavy reliance on overfire air can lead to increased slagging and corrosion in furnaces, particularly with higher-sulfur coals, when LNBs are operated at sub-stoichiometric conditions to reduce fuel-derived NOx in the flame. Therefore, it is desirable

  18. Expert Meeting: Optimized Heating Systems Using Condensing Boilers and Baseboard Convectors

    Energy Technology Data Exchange (ETDEWEB)

    Arena, L.

    2013-01-01

    On August 11, 2011, in Denver, CO, a Building America Expert Meeting was held in conjunction with the Building America Residential Energy Efficiency Technical Update Meeting, to review and discuss results and future plans for research to improve the performance of hydronic heating systems using condensing boilers and baseboard convectors. A meeting objective was to provide an opportunity for other Building America teams and industry experts to provide feedback and specific suggestions for the planned research.

  19. Expert Meeting. Optimized Heating Systems Using Condensing Boilers and Baseboard Convectors

    Energy Technology Data Exchange (ETDEWEB)

    Arena, L. [Steven Winter Associates, Inc., Norwalk, CT (United States)

    2013-01-01

    On August 11, 2011, in Denver, CO, a Building America Expert Meeting was held in conjunction with the Building America Residential Energy Efficiency Technical Update Meeting, to review and discuss results and future plans for research to improve the performance of hydronic heating systems using condensing boilers and baseboard convectors. A meeting objective was to provide an opportunity for other Building America teams and industry experts to provide feedback and specific suggestions for the planned research.

  20. FEASIBILITY ANALYSIS FOR INSTALLING A CIRCULATING FLUIDIZED BED BOILER FOR COFIRING MULTIPLE BIOFUELS AND OTHER WASTES WITH COAL AT PENN STATE UNIVERSITY

    Energy Technology Data Exchange (ETDEWEB)

    Bruce G. Miller; Sharon Falcone Miller; Robert Cooper; John Gaudlip; Matthew Lapinsky; Rhett McLaren; William Serencsits; Neil Raskin; Tom Steitz; Joseph J. Battista

    2003-03-26

    The Pennsylvania State University, utilizing funds furnished by the U.S. Department of Energy's Biomass Power Program, investigated the installation of a state-of-the-art circulating fluidized bed boiler at Penn State's University Park campus for cofiring multiple biofuels and other wastes with coal, and developing a test program to evaluate cofiring biofuels and coal-based feedstocks. The study was performed using a team that included personnel from Penn State's Energy Institute, Office of Physical Plant, and College of Agricultural Sciences; Foster Wheeler Energy Services, Inc.; Foster Wheeler Energy Corporation; Parsons Energy and Chemicals Group, Inc.; and Cofiring Alternatives. The activities included assessing potential feedstocks at the University Park campus and surrounding region with an emphasis on biomass materials, collecting and analyzing potential feedstocks, assessing agglomeration, deposition, and corrosion tendencies, identifying the optimum location for the boiler system through an internal site selection process, performing a three circulating fluidized bed (CFB) boiler design and a 15-year boiler plant transition plan, determining the costs associated with installing the boiler system, developing a preliminary test program, determining the associated costs for the test program, and exploring potential emissions credits when using the biomass CFB boiler.

  1. 纯聚脲技术应用于金属腐蚀防护的技术优势及展望%Technical Advantages and Prospects of Pure Polyurea Technology Applied in Metal Corrosion Protection

    Institute of Scientific and Technical Information of China (English)

    高金岗; 李晶; 黄微波; 何鑫; 陈凯华

    2014-01-01

    Several important metal corrosion mechanism were introduced. The metal corrosion protection principle of isolation,corrosion inhibitor and electrochemical protection etc. and the application situation were reviewed. The definition of pure polyurea and the technology advantage of pure polyurea technology applied in the metal corrosion protection were expounded. The applicaton technology point of the pure polyurea in the process of metal corrosion protection was introduced. It pointed out that pure polyurea technology had absolute advantages to deal with various complex environment of metal corrosion and would have more extensive application prospect in the future.%介绍了几种重要的金属腐蚀机理,并综述了隔离法、缓蚀剂法、电化学保护法等几种常见的金属腐蚀防护方法的原理以及应用情况。重点阐述了纯聚脲的定义及其应用于金属腐蚀防护的技术优势,并介绍了金属腐蚀防护过程中纯聚脲的施工工艺要领。指出纯聚脲技术对于应对各种复杂的金属腐蚀环境具有绝对优势,在未来金属腐蚀防护领域中将有更加广阔的应用前景。

  2. Investigation on the Recent Research Trend in the Corrosion Behaviour of Stainless Steel Weldment

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hwan Tae; Kil, Sang Cheol [Korea Institute of Science and Technology Information, Seoul (Korea, Republic of); Hwang, Woon Suk [Inha University, Incheon (Korea, Republic of)

    2011-06-15

    The research trend in the corrosion behaviour of stainless steel weldment has been reviewed. The welding technology plays an important role in the fabrication of structure such as chemical plant, power plant, because welding can influence various factors in the performance of plant and equipment. This has led to an increasing attention towards the corrosion behaviour of weldment which has been one of the major issues for both welding and corrosion research engineers. The aim of this paper is to give a short survey of the recent technical trends of welding and corrosion including the electrochemical corrosion, stress corrosion cracking, and corrosion fatigue in connection with the welding materials, welding process, and welding fabrication. This study covers the corrosion behaviour of stainless steel weldment collected from the COMPENDEX DB analysis of published papers, research subject and research institutes.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-05-15

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

  4. Fireside corrosion of nickel base alloys in future 700 C coal fired power plants; Rauchgasseitige Korrosion von Nickelbasislegierungen fuer zukuenftige 700 C-Dampfkraftwerke

    Energy Technology Data Exchange (ETDEWEB)

    Luettschwager, Frank

    2011-09-27

    Coal is still the most important energy source in Germany. In 2009 it produced 42.9 % of the overall German electrical power. Coal is available world-wide in large quantities and can be delivered economically. One of the possible ways to reduce CO{sub 2} pollution is the increase of efficiency of coal fired power plants, which requires steam conditions of up to 700 C - 730 C and 350 bar. Because many German power units will reach the end of their technical lifespan in a few years or the following decade, one will have the possibility to build up modern types of power plants with increased efficiency of more than 50 %. Some international standards (European Pressure Equipment Directive or ASME Boiler and Pressure Vessel Code) require 100 000 hour creep rupture strength of 100 MPa at 750 C. Therefore, nickel base alloys are in the focus of material qualification processes. Nickel base alloys are well investigated due to their hot corrosion behaviour. It is known that sodium sulphate may generate hot corrosion on those alloys at temperatures above its melting point of 884 C. On nickel base alloys an eutectic mixture of nickel sulphate and sodium sulphate with a melting point of 671 C can be generated, which leads to accelerated corrosion. This work examines, whether the high amount of sulphur and alkali metals will induce hot corrosion at the estimated working temperature on devices manufactured from nickel base alloy. Two synthetic coal ash deposits, according to the chemical composition of hard coal and lignite, and typical flue gases with and without sulphur dioxide were blended of pure agents. The reactions of the deposits with heater tubes' materials and synthetic flue gases are examined in the temperature range from 650 C to 800 C and different time ranges up to 2000 hours. The corroded specimen are examined with SEM/EDX to identify relevant corrosion products and determine the corrosivity of deposited compounds. Deposits increase the corrosion rate of

  5. Erosion corrosion in a wet steam loop

    International Nuclear Information System (INIS)

    In a technical loop of a power plant erosion corrosion behaviour of the steels C 22.8, 15 Mo 3 and 10 Cr Mo 9 10 was investigated in test periods up to 78 days under definite conditions in wet steam of a relative steam content of about 75% at a temperature of 185 to 2000C and flow velocities up to 180 m/s. For comparison one test was carried out also in hot steam. By gravimetric, metallographic, SEM- and X-ray-diffraction analysis essential information was obtained on the kinetics of erosion corrosion and the structure of oxide coatings. The rate of erosion corrosion shows a high dependence on time and steel composition and decrease in the above mentioned order. Structure and quality of the oxide layer also show a remarkable dependence on steel composition. (orig.)

  6. Corrosion resistance of titanium alloys for dentistry

    International Nuclear Information System (INIS)

    Titanium and its alloys belong to biomaterials which the application scope in medicine increases. Some properties of the alloys, such as high mechanical strength, low density, low Young's modulus, high corrosion resistance and good biotolerance decide about it. The main areas of the application of titanium and its alloys are: orthopedics and traumatology, cardiosurgery, faciomaxillary surgery and dentistry. The results of investigations concerning the corrosion resistance of the technical titanium and Ti6Al14V alloy and comparatively a cobalt alloy of the Vitallium type in the artificial saliva is presented in the work. Significantly better corrosion resistance of titanium and the Ti6Al14V than the Co-Cr-Mo alloy was found. (author)

  7. Probability of detection for corrosion defects

    Energy Technology Data Exchange (ETDEWEB)

    Rudlin, J.R.; Kenzie, B.W. [TWI Ltd., Cambridge (United Kingdom)

    2002-07-01

    A variety of NDT techniques have been made available by the industry to assess the wall thickness of a pipe. These include manual ultrasonics, automated ultrasonics, magnetic flux leakage, guided wave ultrasonics and pulsed eddy current. These methods have been evaluated for the detection and sizing of localised corrosion on a set of around 50 test pipes in a project carried out by TWI, University College London, Technical Software Consultants and Bureau Veritas. Trials of the inspection methods were carried out in various situations including coated pipe and for corrosion under insulation. This paper describes the trials carried out and discusses some of the difficulties involved in producing and using probability of detection data when assessing corrosion. (orig.)

  8. A novel capacitance sensor for fireside corrosion measurement.

    Science.gov (United States)

    Ban, Heng; Li, Zuoping

    2009-11-01

    Fireside corrosion in coal-fired power plants is a leading mechanism for boiler tube failures. Online monitoring of fireside corrosion can provide timely data to plant operators for mitigation implementation. This paper presents a novel sensor concept for measuring metal loss based on electrical capacitance. Laboratory-scale experiments demonstrated the feasibility of design, fabrication, and operation of the sensor. The fabrication of the prototype sensor involved sputtering deposition of a thin metal coating with varying thickness on a ceramic substrate. Corrosion metal loss resulted in a proportional decrease in electrical capacitance of the sensor. Laboratory experiments using a muffle furnace with an oxidation environment demonstrated that low carbon steel coatings on ceramic substrate survived cyclic temperatures over 500 degrees C. Measured corrosion rates of sputtered coating in air had an Arrhenius exponential dependence on temperature, with metal thickness loss ranging from 2.0 nm/h at 200 degrees C to 2.0 microm/h at 400 degrees C. Uncertainty analysis indicated that the overall measurement uncertainty was within 4%. The experimental system showed high signal-to-noise ratio, and the sensor could measure submicrometer metal thickness changes. The laboratory experiments demonstrated that the sensor concept and measurement system are capable of short term, online monitoring of metal loss, indicating the potential for the sensor to be used for fireside corrosion monitoring and other metal loss measurement.

  9. A novel capacitance sensor for fireside corrosion measurement

    Science.gov (United States)

    Ban, Heng; Li, Zuoping

    2009-11-01

    Fireside corrosion in coal-fired power plants is a leading mechanism for boiler tube failures. Online monitoring of fireside corrosion can provide timely data to plant operators for mitigation implementation. This paper presents a novel sensor concept for measuring metal loss based on electrical capacitance. Laboratory-scale experiments demonstrated the feasibility of design, fabrication, and operation of the sensor. The fabrication of the prototype sensor involved sputtering deposition of a thin metal coating with varying thickness on a ceramic substrate. Corrosion metal loss resulted in a proportional decrease in electrical capacitance of the sensor. Laboratory experiments using a muffle furnace with an oxidation environment demonstrated that low carbon steel coatings on ceramic substrate survived cyclic temperatures over 500 °C. Measured corrosion rates of sputtered coating in air had an Arrhenius exponential dependence on temperature, with metal thickness loss ranging from 2.0 nm/h at 200 °C to 2.0 μm/h at 400 °C. Uncertainty analysis indicated that the overall measurement uncertainty was within 4%. The experimental system showed high signal-to-noise ratio, and the sensor could measure submicrometer metal thickness changes. The laboratory experiments demonstrated that the sensor concept and measurement system are capable of short term, online monitoring of metal loss, indicating the potential for the sensor to be used for fireside corrosion monitoring and other metal loss measurement.

  10. The microbial corrosion; La corrosion microbienne

    Energy Technology Data Exchange (ETDEWEB)

    Beech, I.B. [University of Portsmouth, School of Pharmacy - Biomedical Science, Chemistry-Physics and Radiography, Portsmouth (United Kingdom)

    1999-02-01

    Underestimated for a long time, corrosion due to microorganisms induces degradation, sometimes fulminant, of a lot of metallic structures in the world. Searchers are using plentiful analytical tools to understand this phenomenon. (O.M.)

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

    Directory of Open Access Journals (Sweden)

    Joner Oliveira Alves

    2014-10-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-12-31

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

  13. Analysis of cracking of co-extruded recovery boiler floor tubes

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-08-01

    Cracking of the stainless steel layer in co-extruded 304L/SA210 tubing used in black liquor recovery boilers is being found in an ever-increasing number of North American pulp and paper mills. Because of the possibility of a tube failure, this is a significant safety issue, and, because of the extra time required for tube inspection and repair, this can become an economic issue as well. In a project funded by the U.S. Department of Energy and given wide support among paper companies, boiler manufacturers, and tube fabricators, studies are being conducted to determine the cause of the cracking and to identify alternate materials and/or operating procedures to prevent tube cracking. Examination of cracked tubes has permitted characterization of crack features, and transmission electron microscopy is providing information about the thermal history, particularly cyclic thermal exposures, that tubes have experienced. Neutron and x-ray diffraction techniques are being used to determine the residual stresses in as-fabricated tube panels and exposed tubes, and finite element modeling is providing information about the stresses the tubes experience during operation. Laboratory studies are being conducted to determine the susceptibility of the co-extruded 304L/SA210 tubes to stress corrosion cracking, thermal fatigue, and corrosion in molten smelt. This paper presents the current status of these studies. On the basis of all of these studies, recommendations for means to prevent tube cracking will be offered.

  14. Analysis and study on the performance variation of SCR DeNOx catalyst of Coal-Fired Boilers

    International Nuclear Information System (INIS)

    Nitrogen oxides (NOx) are one kind of harmful substances from the burning process of fossil fuel and air at high temperature. NOx emissions cause serious pollution on atmospheric environment. In this paper, coal-fired utility boilers were chosen as the object, NOx formation mechanism and control were studied, and SCR deNOx technology was used to control NOx emissions from coal-fired boilers. Analyzed the relationship between deNOx efficiency and characteristics of SCR DeNOx catalyst. Through analysis, affecting SCR DeNOx catalyst failure factors, change law of catalytic properties and technical measures to extend the service life of the catalyst were gotten. (author)

  15. Theory and Practice of steel surface protection in boilers; Schutz der Stahloberflaechen von Dampferzeugern. Theorie und Praxis

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, J.P.; Daucik, K. [SV Produktion a.m.b.a., Skaerbaek, Fredericia (Denmark); Smitshuysen, E.F. [Faelleskemikerne, I/S Vestkraft, Esbjerg (Denmark)

    1999-10-01

    Protective magnetite steel surface layers developing in steam generators may be subject to aggressive attacks. However, even if general guidelines for the bulk water are met with respect to the water purity (acid conductivity) and conditioning chemicals, damage can occur. The reason may be the disregarding of interaction among material, design and chemistry. Different boiler water treatments are discussed in detail. The influence of pressure and pH on the stability of the protective layer is described. Experience on how solid alkaline conditioning combined with inadequate design can result in severe corrosion and boiler tube failures is outlined. It is also being described how simple modifications of the boiler design can resolve solid alkaline corrosion. (orig.) [Deutsch] Magnetit-Schutzschichten, die sich auf den Stahlflaechen von Dampferzeugern ausbilden, sind oftmals aggressiven Angriffen ausgesetzt. Daraus koennen sich Schaeden entwickeln, die nur durch optimales Speise- und Kesselwasser vermieden werden koennen. Doch selbst bei Einhaltung allgemeiner Richtlinien im Hinblick auf Wasserreinheit (Saeureleitfaehigkeit) und Alkalisierungsmittel koennen Schaeden auftreten, wenn bedeutende, sich gegenseitig beeinflussende Parameter, wie Werkstoffwahl, Auslegung und chemische Fahrweise, nicht ausreichend beachtet werden. Die unterschiedlichen Moeglichkeiten der Wasserkonditionierung werden detailliert eroertert. Druck und pH-Wert nehmen ebenfalls Einfluss auf die Stabilitaet der Schutzschicht. Die Autoren berichten ueber Faelle, in denen feste Alkalisierungsmittel in Kombination mit einer nicht geeigneten Kesselkonstruktion zu schwerwiegender Korrosion und Rohrschaeden gefuehrt haben. Weiterhin wird gezeigt, wie dank einfacher Veraenderungen am Dampferzeuger das durch feste Alkalisierungsmittel hervorgerufene Korrosionsproblem geloest werden kann. (orig.)

  16. 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)

  17. 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.

  18. Monitoring Microbially Influenced Corrosion

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    Abstract Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria (SRB). The applicability and reliability of a number of corrosion monitoring techniques for monitoring MIC has been evaluated in experiments...... and diffusional effects and unreliable corrosion rates, when biofilm and ferrous sulphide corrosion products cover the steel surface. Corrosion rates can be overestimated by a factor of 10 to 100 by electrochemical techniques. Weight loss coupons and ER are recommended as necessary basic monitoring techniques....... EIS might be used for detection of MIC as the appearance of very large capacitances can be attributed to the combined ferrous sulphide and biofilm formation. Capacitance correlates directly with sulphide concentration in sterile sulphide media. Keywords: Corrosion monitoring, carbon steel, MIC, SRB...

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

    Directory of Open Access Journals (Sweden)

    Khaustov Sergei

    2015-01-01

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

  20. MÖSBAUER INVESTIGATION OF CORROSION PROCESSES AND PRODUCTS

    OpenAIRE

    Meisel, W.

    1980-01-01

    The qualitative and quantitative Mössbauer spectroscopic phase analysis is a very useful tool for investigating corrosion processes and products. Its nondestructive character as well as the fact that also amorphous products can be studied, are its most important advantages as compared with other appropriate methods, as e.g. Röntgen diffraction. Because of the great technical importance, the corrosion of iron and steel will be considered in some detail. By use of a simple model of atmospheric ...

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

    International Nuclear Information System (INIS)

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

  2. Development and testing of a high efficiency advanced coal combustor: Phase 3 industrial boiler retrofit. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Patel, R.L.; Thornock, D.E.; Miller, B.G.; Scaroni, A.W.; McGowan, J.G.

    1998-03-01

    Economics and/or political intervention may one day dictate the conversion from oil or natural gas to coal in boilers that were originally designed to burn oil or gas. In recognition of this future possibility the US Department of Energy, Federal Energy Technical Center (DOE-FETC) supported a program led by ABB Power Plant Laboratories with support from the Energy and Fuels Research Center of Penn State University with the goal of demonstrating the technical and economic feasibility of retrofitting a gas/oil designed boiler to burn micronized coal. In support of the overall goal the following specific objectives were targeted: develop a coal handling/preparation system that can meet the technical and operational requirements for retrofitting microfine coal on a boiler designed for burning oil or natural gas; maintain boiler thermal performance in accordance with specifications when burning oil or natural gas; maintain NOx emissions at or below 0.6 lb NO{sub 2} per million Btu; achieve combustion efficiencies of 98% or higher; and determine economic payback periods as a function of key variables.

  3. Erosion-corrosion; Erosionkorrosion

    Energy Technology Data Exchange (ETDEWEB)

    Aghili, B

    1999-05-01

    A literature study on erosion-corrosion of pipings in the nuclear industry was performed. Occurred incidents are reviewed, and the mechanism driving the erosion-corrosion is described. Factors that influence the effect in negative or positive direction are treated, as well as programs for control and inspection. Finally, examples of failures from databases on erosion-corrosion are given in an attachment 32 refs, 16 figs, tabs

  4. Remote measurement of corrosion using ultrasonic techniques

    International Nuclear Information System (INIS)

    Supercritical water oxidation (SCWO) technology has the potential of meeting the US Department of Energy's treatment requirements for mixed radioactive waste. A major technical constraint of the SCWO process is corrosion. Safe operation of a pilot plant requires monitoring of the corrosion rate of the materials of construction. A method is needed for measurement of the corrosion rate taking place during operation. One approach is to directly measure the change in wall thickness or growth of oxide layer at critical points in the SCWO process. In FY-93, a brief survey of the industry was performed to evaluate nondestructive evaluation (NDE) methods for remote corrosion monitoring in supercritical vessels. As a result of this survey, it was determined that ultrasonic testing (UT) methods would be the most cost-effective and suitable method of achieving this. Therefore, the objective for FY-94 was to prove the feasibility of using UT to monitor corrosion of supercritical vessels remotely during operation without removal of the insulation

  5. 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.

  6. Computer simulation of the fire-tube boiler hydrodynamics

    Science.gov (United States)

    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. Innovative clean coal technology (ICCT): demonstration of selective catalytic reduction (SCR) technology for the control of nitrogen oxide (NOx) emission from high-sulfur, coal-fired boilers - economic evaluation of commercial-scale SCR applications for utility boilers

    International Nuclear Information System (INIS)

    This report presents the results of an economic evaluation produced as part of the Innovative Clean Coal Technology project, which demonstrated selective catalytic reduction (SCR) technology for reduction of NOx emissions from utility boilers burning U.S. high-sulfur coal. The document includes a commercial-scale capital and O ampersand M cost evaluation of SCR technology applied to a new facility, coal-fired boiler utilizing high-sulfur U.S. coal. The base case presented herein determines the total capital requirement, fixed and variable operating costs, and levelized costs for a new 250-MW pulverized coal utility boiler operating with a 60-percent NOx removal. Sensitivity evaluations are included to demonstrate the variation in cost due to changes in process variables and assumptions. This report also presents the results of a study completed by SCS to determine the cost and technical feasibility of retrofitting SCR technology to selected coal-fired generating units within the Southern electric system

  9. Corrosion in the oil industry

    Energy Technology Data Exchange (ETDEWEB)

    Brondel, D. (Sedco Forex, Montrouge (France)); Edwards, R. (Schlumberger Well Services, Columbus, OH (United States)); Hayman, A. (Etudes et Productions Schlumberger, Clamart (France)); Hill, D. (Schlumberger Dowell, Tulsa, OK (United States)); Mehta, S. (Schlumberger Dowell, St. Austell (United Kingdom)); Semerad, T. (Mobil Oil Indonesia, Inc., Sumatra (Indonesia))

    1994-04-01

    Corrosion costs the oil industry billions of dollars a year, a fact that makes the role of the corrosion engineer an increasingly important one. Attention is paid to how corrosion affects every aspect of exploration and production, from offshore rigs to casing. Also the role of corrosion agents such as drilling and production fluids is reviewed. Methods of control and techniques to monitor corrosion are discussed, along with an explanation of the chemical causes of corrosion. 21 figs., 32 refs.

  10. NOx EMISSIONS PRODUCED WITH COMBUSTION OF POWDER RIVER BASIN COAL IN A UTILITY BOILER

    Energy Technology Data Exchange (ETDEWEB)

    John S. Nordin; Norman W. Merriam

    1997-04-01

    The objective of this report is to estimate the NOx emissions produced when Powder River Basin (PRB) coal is combusted in a utility boiler. The Clean Air Act regulations specify NOx limits of 0.45 lb/mm Btu (Phase I) and 0.40 lb/mm Btu (Phase II) for tangentially fired boilers, and 0.50 lb/mm 13tu (Phase II) and 0.46 lb/mm Btu (Phase II) for dry-bottom wall-fired boilers. The Clean Air Act regulations also specify other limits for other boiler types. Compliance for Phase I has been in effect since January 1, 1996. Compliance for Phase II goes into effect on January 1, 2000. Emission limits are expressed as equivalent NO{sub 2} even though NO (and sometimes N{sub 2}O) is the NOx species emitted during combustion. Regulatory agencies usually set even lower NOx emission limits in ozone nonattainment areas. In preparing this report, Western Research Institute (WRI) used published test results from utilities burning various coals, including PRB coal, using state-of-the art control technology for minimizing NOx emissions. Many utilities can meet Clean Air Act NOx emission limits using a combination of tight combustion control and low-NOx burners and by keeping furnaces clean (i.e., no slag buildup). In meeting these limits, some utilities also report problems such as increased carbon in their fly ash and excessive furnace tube corrosion. This report discusses utility experience. The theory of NOx emission formation during coal combustion as related to coal structure and how the coal is combusted is also discussed. From this understanding, projections are made for NOx emissions when processed PRB coal is combusted in a test similar to that done with other coals. As will be shown, there are a lot of conditions for achieving low NOx emissions, such as tight combustion control and frequent waterlancing of the furnace to avoid buildup of deposits.

  11. NaK pool-boiler solar receiver durability bench test. Volume 2: Metallurgical analysis

    Science.gov (United States)

    Goods, S. H.; Bradshaw, R. W.

    1995-01-01

    The principal materials used in the construction of a NaK based pool-boiler were analyzed. The device, operated for 7500 hours, accumulated 1000 thermal cycles to a peak temperature of 750 C. Haynes 230, used to fabricate the pool-boiler vessel, was found to perform satisfactorily. Air-side corrosion of the pool-boiler vessel was insignificant. Internal surface of the alloy exhibited some NaK-induced elemental dissolution; this dissolution was somewhat more extensive where the alloy was exposed to the liquid metal compared to regions exposed only to NaK vapor; however, the corresponding metal loss in all regions was inconsequential, never exceeding more than a few microns. Autogenous seam welds of the alloy responded in a similar fashion, exhibiting only minimal metal loss over the course of the experiment. While there was 50% loss in ductility of the alloy there remained adequate ductility for the anticipated operating environment. An enhanced boiling nucleation surface comprised of stainless steel powder brazed to the vessel ID showed no change in its structure. It remained intact, showing no cracking after repeated thermal cycling. Other materials used in the experiment showed more extensive degradation after exposure to the NaK. IN 600, used to fabricate thermowells, exhibited extensive surface and intergranular dissolution. Grain boundary dissolution was sufficiently severe in one of the thermowells to cause an air leak, resulting in experiment termination. BNi-3, a brazing alloy used to join the pool-boiler vessel, endcaps and thermowells, showed some dissolution where it was exposed to the NaK as well as thermal aging effects. However, all brazes remained structurally sound. A nickel metal ribbon showed catastrophic dissolution, resulting in the formation of deep (greater than 30 (mu)m) pits and cavities. A zirconium metal foil used to getter oxygen from the NaK became extremely brittle.

  12. Characterization of deposits and their influence on corrosion in waste incineration plants in Denmark

    DEFF Research Database (Denmark)

    Montgomery, Melanie; Larsen, OH

    2001-01-01

    A program has been initiated in Denmark to investigate the aggressive environment in various waste incineration plants. The results described are the preliminary results from one waste incineration plant. Deposits and corrosion products have been removed from various locations in the boiler....... These have been analyzed with respect to morphology and composition using electron microscopy techniques. This results in a map indicating the conditions that exist throughout the plant. This can be compared with a map of flue gas and steam temperatures through the plant and with the amount of corrosion...

  13. 46 CFR 56.50-30 - Boiler feed piping.

    Science.gov (United States)

    2010-10-01

    ... for water tube boilers shall have fresh water connections only. Care shall be taken to prevent the... 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)...

  14. 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 COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING PERIODIC TESTS AND INSPECTIONS Tests and Inspections of Boilers § 61.05-20 Boiler safety valves. Each safety valve for a...

  15. Lower price for solar boilers must improve market penetration

    International Nuclear Information System (INIS)

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

  16. 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...

  17. 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 ...

  18. 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.

  19. 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.

  20. Development of 18Cr-9Ni-W-Nb-V-N Austenitic Stainless Steel Tube for Thermal Power Boilers

    Science.gov (United States)

    Ishitsuka, Tetsuo; Mimura, Hiroyuki

    An 18Cr-9Ni-W-Nb-V-N austenitic stainless steel tube for thermal power boilers has been newly developed. The high temperature mechanical properties and corrosion resistance of the steel were investigated. The creep rupture strength of the developed steel is about 1.5 times as high as that of SUS347HTB, and is almost the same as that of Ka-SUS310J2TB at 650°C. This excellent creep strength of the steel is mainly due to solid solution strengthening by tungsten and nitrogen, and precipitation strengthening by nitrides of niobium and vanadium. The carbon content of the steel is reduced to 0.03% to improve intergranular corrosion resistance. The steam oxidation resistance and the high temperature corrosion resistance of the tube are almost the same as those of SUS347HTB. Weldability of the developed steel is superior to that of SUS304HTB and SUS310TB. Thus the developed steel is suitable for use as a material for superheater and reheater tubes of thermal power boilers.

  1. Characterization of Encapsulated Corrosion Inhibitors for Environmentally Friendly Smart Coatings

    Science.gov (United States)

    Pearman, B. P.; Calle, L. M.; Zhang, X.; Li, W.; Buhrow, J. W.; Johnsey, M. N.; Montgomery, E. L.; Fitzpatrick, L.; Surma, J. M.

    2015-01-01

    The NASA Kennedy Space Center's Corrosion Technology Lab at the Kennedy Space Center in Florida, U.S.A. has been developing multifunctional smart coatings based on the microencapsulation of environmentally friendly corrosion indicators, inhibitors and self-healing agents. This allows the incorporation of autonomous corrosion control functionalities, such as corrosion detection and inhibition as well as the self-healing of mechanical damage, into coatings. This paper presents technical details on the characterization of inhibitor-containing particles and their corrosion inhibitive effects using electrochemical and mass loss methods. Three organic environmentally friendly corrosion inhibitors were encapsulated in organic microparticles that are compatible with desired coatings. The release of the inhibitors from the microparticles in basic solution was studied. Fast release, for immediate corrosion protection, as well as long-term release for continued protection, was observed. The inhibition efficacy of the inhibitors, incorporated directly and in microparticles, on carbon steel was evaluated. Polarization curves and mass loss measurements showed that, in the case of 2MBT, its corrosion inhibition effectiveness was greater when it was delivered from microparticles.

  2. New fundamental and environmental aspects of atmospheric corrosion

    International Nuclear Information System (INIS)

    Atmospheric corrosion involves chemical, electrochemical, and physical processes in three phases (solid, liquid, and gas) and two interfaces (solid/liquid and liquid/gas). Because of inherent experimental and conceptual difficulties, scientific efforts to characterize this highly complex interfacial regime came relatively late into the field. With the access and development of surface and interface sensitive analytical techniques, it has lately become possible to perform molecular in situ analyses of the interfaces involved in atmospheric corrosion. This lecture presents some highlights from our fundamental research in atmospheric corrosion, performed at the Royal Institute of Technology in Stockholm, Sweden. It includes results from the most recent efforts in our research group to provide a molecular understanding of the interfacial regime that governs atmospheric corrosion. Using copper or zinc as substrate and carboxylic acid as corrosion stimulator in the humidity-containing atmosphere, results have been obtained with particular emphasis on probing the metal oxide/water interface (by infrared reflection absorption spectroscopy (IRAS) combined with the quartz crystal microbalance (QCM) and sum frequency generation (SFG)) and the water/gas interface (by SFG), respectively. While research in atmospheric corrosion traditionally has aimed at understanding how the environment influences the metal, the opposite question- how the metal influences the environment during atmospheric corrosion- may be of equally technical importance. Some examples of on-going research on new environmental aspects of atmospheric corrosion of zinc will also be presented. (Author) 9 refs

  3. New fundamental and environmental aspects of atmospheric corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Leygraf, C.

    2009-07-01

    Atmospheric corrosion involves chemical, electrochemical, and physical processes in three phases (solid, liquid, and gas) and two interfaces (solid/liquid and liquid/gas). Because of inherent experimental and conceptual difficulties, scientific efforts to characterize this highly complex interfacial regime came relatively late into the field. With the access and development of surface and interface sensitive analytical techniques, it has lately become possible to perform molecular in situ analyses of the interfaces involved in atmospheric corrosion. This lecture presents some highlights from our fundamental research in atmospheric corrosion, performed at the Royal Institute of Technology in Stockholm, Sweden. It includes results from the most recent efforts in our research group to provide a molecular understanding of the interfacial regime that governs atmospheric corrosion. Using copper or zinc as substrate and carboxylic acid as corrosion stimulator in the humidity-containing atmosphere, results have been obtained with particular emphasis on probing the metal oxide/water interface (by infrared reflection absorption spectroscopy (IRAS) combined with the quartz crystal microbalance (QCM) and sum frequency generation (SFG)) and the water/gas interface (by SFG), respectively. While research in atmospheric corrosion traditionally has aimed at understanding how the environment influences the metal, the opposite question- how the metal influences the environment during atmospheric corrosion- may be of equally technical importance. Some examples of on-going research on new environmental aspects of atmospheric corrosion of zinc will also be presented. (Author) 9 refs.

  4. Waterside corrosion of zirconium alloys in nuclear power plants

    International Nuclear Information System (INIS)

    Technically the study of corrosion of zirconium alloys in nuclear power reactors is a very active field and both experimental work and understanding of the mechanisms involved are going through rapid changes. As a result, the lifetime of any publication in this area is short. Because of this it has been decided to revise IAEA-TECDOC-684 - Corrosion of Zirconium Alloys in Nuclear Power Plants - published in 1993. This updated, revised and enlarged version includes major changes to incorporate some of the comments received about the first version. Since this review deals exclusively with the corrosion of zirconium and zirconium based alloys in water, and another separate publication is planned to deal with the fuel-side corrosion of zirconium based fuel cladding alloys, i.e. stress corrosion cracking, it was decided to change the original title to Waterside Corrosion of Zirconium Alloys in Nuclear Power Plants. The rapid changes in the field have again necessitated a cut-off date for incorporating new data. This edition incorporates data up to the end of 1995; including results presented at the 11 International Symposium on Zirconium in the Nuclear Industry held in Garmisch-Partenkirchen, Germany, in September 1995. The revised format of the review now includes: Introductory chapters on basic zirconium metallurgy and oxidation theory; A revised chapter discussing the present extent of our knowledge of the corrosion mechanism based on laboratory experiments; a separate and revised chapter discussing hydrogen uptake; a completely reorganized chapter summarizing the phenomenological observations of zirconium alloy corrosion in reactors; a new chapter on modelling in-reactor corrosion; a revised chapter devoted exclusively to the manner in which irradiation might influence the corrosion process; finally, a summary of our present understanding of the corrosion mechanisms operating in reactor

  5. Impact of Aluminum on Anticipated Corrosion in a Flooded spent nuclear fuel Multi -Canister Overpack

    International Nuclear Information System (INIS)

    Corrosion reactions in a flooded MCO are examined to determine the impact of aluminum corrosion products (from aluminum basket grids and spacers) on bound water estimates and subsequent fuel/environment reactions during storage. The mass and impact of corrosion products were determined to be insignificant, validating the choice of aluminum as an MCO component and confirming expectations that no changes to the Technical Databook or particulate mass or water content are necessary

  6. Impact of Aluminum on Anticipated Corrosion in a Flooded SNF Multi Canister Overpack (MCO)

    Energy Technology Data Exchange (ETDEWEB)

    DUNCAN, D.R.

    1999-07-06

    Corrosion reactions in a flooded MCO are examined to determine the impact of aluminum corrosion products (from aluminum basket grids and spacers) on bound water estimates and subsequent fuel/environment reactions during storage. The mass and impact of corrosion products were determined to be insignificant, validating the choice of aluminum as an MCO component and confirming expectations that no changes to the Technical Databook or particulate mass or water content are necessary.

  7. Corrosion evaluation technology

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Uh Chul; Han, Jeong Ho; Nho, Kye Ho; Lee, Eun Hee; Kim, Hong Pyo; Hwang, Seong Sik; Lee, Deok Hyun; Hur, Do Haeng; Kim, Kyung Mo

    1997-09-01

    A multifrequency ACPD system was assembled which can measure very small crack. Stress corrosion cracking test system with SSRT operating high temperature was installed. Stress corrosion cracking test of newly developed alloy 600 and existing alloy 600 was carried out in steam atmosphere of 400 deg C. No crack was observed in both materials within a test period of 2,000 hrs. Corrosion fatigue test system operating at high temperature was installed in which fatigue crack was measured by CDPD. Lead enhanced the SCC of the Alloy 600 in high temperature water, had a tendency to modify a cracking morphology from intergranular to transgranular. Pit initiation preferentially occurred at Ti-rich carbide. Resistance to pit initiation decreased with increasing temperature up to 300 deg C. Test loop for erosion corrosion was designed and fabricated. Thin layer activation technique was very effective in measuring erosion corrosion. Erosion corrosion of a part of secondary side pipe was evaluated by the Check Family Codes of EPRI. Calculated values of pipe thickness by Check Family Codes coincided with the pipe thickness measured by UT with an error of {+-} 20%. Literature review on turbine failure showed that failure usually occurred in low pressure turbine rotor disc and causes of failure are stress corrosion cracking and corrosion fatigue. (author). 12 refs., 20 tabs., 77 figs.

  8. Utilisation of forest chips, produced with different harvesting chains, in fluidised bed boilers of large power plants; Erilaisten korjuuketjujen tuottaman metsaehakkeen kaeyttoe suurten voimaloiden leijukerroskattiloissa - PUUT08

    Energy Technology Data Exchange (ETDEWEB)

    Orjala, M.; Ingalsuo, R. [VTT Energy, Jyvaeskylae (Finland)

    2001-07-01

    When combusting wood fuels the chemical composition of woof fuels can cause fouling and high-temperature corrosion of the heat transfer and superheater surfaces of the boiler. Problems are caused especially by forest chips, which include high quantities of needles and thin branches. Even though low alkali metal and chlorine contents are typical for wood fuels, the problem is that they are easily vaporised during combustion. Depending on the combustion conditions, the alkali metals can be oxidised to alkali metal oxides or they can form sulphates or chlorides. When combustion pure wood the sulphur content in combustion process is low and alkali metal compounds form chlorides easily, which can be condensed on the heat transfer surfaces of the boiler and form a significant high-temperature corrosion risk. If the sulphur content of the combustion process is increased e.g. by additional utilisation of peat, the chemistry of alkali metals is directed to formation of alkali metal sulphates instead of chlorides, and the chlorine liberated in the furnace forms gaseous hydrogen chloride (HCI). Hydrogen chloride, formed in combustion of wood fuels, is transferred in low concentrations in flue gases out of the boiler so it does not cause significant chlorine corrosion or emission risk. (orig.)

  9. Deposit Probe Measurements in Large Biomass-Fired Grate Boilers and Pulverized-Fuel Boilers

    DEFF Research Database (Denmark)

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

    2014-01-01

    temperatures (>900 °C). At lower flue gas temperatures, the deposits can be removed by soot blowing. The required soot blower impact pressure is strongly influenced by the surface temperature, such that a high surface temperature makes the deposit more difficult to remove. During straw/wood......-up increased with the K-content of the fuel ash and fly ash for grate-fired boilers. For suspension-fired boilers, deposition rates are comparatively low for wood-firing and increase with increasing fuel straw shares. Shedding of deposits occurs by melting during straw-firing on a grate at high flue gas......-firing in suspension-fired boilers, shedding occurred by debonding with incomplete removal at flue gas temperatures of 600–1000 °C and by debonding with complete removal during wood-firing in suspension-fired boilers at high flue gas temperatures (1300 °C). Shedding events were not observed during wood suspension...

  10. General Corrosion and Localized Corrosion of the Drip Shield

    Energy Technology Data Exchange (ETDEWEB)

    F. Hua; K. Mon

    2003-06-24

    The recommended waste package (WP) design is described in BSC (2001a). The design includes a double-wall WP underneath a protective drip shield (DS) (BSC 2003a). The purpose of the process-level models developed in this report is to model dry oxidation (DOX), general corrosion (GC) and localized corrosion (LC) of the DS plate material, which is made of Ti Grade 7. The DS design also includes structural supports fabricated from Ti Grade 24. Degradation of Ti Grade 24 is not considered in this report. The DS provides protection for the waste package outer barrier (WPOB) both as a barrier to seepage water contact and a physical barrier to potential rockfall. This Model Report (MR) serves as a feed to the Integrated Waste Package Degradation Model (IWPD) analyses, and was developed in accordance with the Technical Work Plan (TWP) (BSC 2002a). The models contained in this report serve as a basis to determine whether or not the performance requirements for the DS can be met.

  11. Non-destructive methods are useful for detecting any kind of corrosion

    International Nuclear Information System (INIS)

    Non-destructive methods are used to detect and follow the evolution of corrosion. The right method to use depends on the type of corrosion we want to study and on the conditions in which the control is performed. The acoustic emission testing (AET) is one of the most promising. Uniform corrosion and localized corrosion can be studied by AET and technologies based on AET are being developed to control the state of pressure vessels or of gas or liquid containers. Other fields of applications are under investigation: the control of the propagation of fissures generated by stress corrosion or by hydrogen embrittlement or by corrosion fatigue. The CETIM (technical center of mechanic industries) has realized a database that gathers all the work made concerning AET and the detection of corrosion. (A.C.)

  12. Field test corrosion experiences when co-firing straw and coal: 10 year status within Elsam

    DEFF Research Database (Denmark)

    Frandsen, Rasmus Berg; Montgomery, Melanie; Larsen, Ole Hede

    2007-01-01

    and straw at the 150 MW pulverized coal fired boiler Studstrup unit 1. Two exposure series lasting 3000 hours each were performed for co-firing 10 and 20% of straw (% energy basis) with coal. Using built in test tubes in the hot end of the actual superheaters and air/water cooled corrosion probes...... of the 350 MW pulverized coal fired boiler, Studstrup unit 4, into a co-firing boiler with straw in 2002. During the rebuilding, test tube sections of X20CrMoV12 1 and TP347H FG were built into the superheater and the reheater loops. The temperature ranges during these exposures was for the steam from 470...... sulphate on superheater tubes resulting in increased corrosion rates. From field experimental results this paper show, that by co-firing straw with coal, corrosion rates can be brought down to an acceptable level. This paper firstly deals with the results from a demonstration program co-firing coal...

  13. Fireside corrosion testing of candidate superheater tube alloys, coatings, and claddings -- Phase 2 field testing

    Energy Technology Data Exchange (ETDEWEB)

    Blough, J.L.; Seitz, W.W.; Girshik, A. [Foster Wheeler Development Corp., Livingston, NJ (United States)

    1998-06-01

    In Phase 1 of this project, laboratory experiments were performed on a variety of developmental and commercial tubing alloys and claddings by exposing them to fireside corrosion tests which simulated a superheater or reheater in a coal-fired boiler. Phase 2 (in situ testing) has exposed samples of 347, RA85H, HR3C, RA253MA, Fe{sub 3}Al + 5Cr, Ta-modified 310, NF 709, 690 clad, 671 clad, and 800HT for up to approximately 16,000 hours to the actual operating conditions of a 250-MW, coal-fired boiler. The samples were installed on air-cooled, retractable corrosion probes, installed in the reheater cavity, and controlled to the operating metal temperatures of an existing and advanced-cycle, coal-fired boiler. Samples of each alloy were exposed for 4,483, 11,348, and 15,883 hours of operation. The present results are for the metallurgical examination of the corrosion probe samples after the full 15,883 hours of exposure. A previous topical report has been issued for the 4,483 hours of exposure.

  14. Needs-driven soot blowing in waste boilers; Behovsstyrd sotblaasning i avfallspannor

    Energy Technology Data Exchange (ETDEWEB)

    Niklasson, Fredrik; Davidsson, Kent

    2009-09-15

    The increased use of alternative and waste fuels has resulted in an increased number of plants having trouble with fouling and corrosion on boiler banks and superheater tubes. Frequent sootblowing will keep the surfaces relatively clean, but on the other hand, it may erode the tube material. An intelligent sootblowing system will initiate sootblowings on individual tube banks only when needed for that specific tube bank. Such a system depends on the detection of the degree of fouling of specific tube banks. In this project, the conditions for an intelligent sootblowing system at the waste fired boilers in Boraas are investigated from measured flows, temperatures and pressure drop. New thermocouples at the water tubes between the banks of the economiser have been installed and connected to the control and monitoring system of the boiler. From measured temperatures and flows, heat transfer coefficients are calculated and used to detect the fouling on the heat exchangers. A pressure transducer has been altered to measure the pressure over the boiler bank. At the superheaters, the measurements show a significant improvement of the heat transfer coefficients immediately following sootblowing. Thereafter, the heat transfer coefficients decline more slowly, almost linearly. The measurements indicate that the fouling rate is almost same for the two superheaters and do not motivate individual sootblowing sequences of the two superheaters. The pressure drop over the boiler bank was found too insensitive a measure to be used as an indicator for an intelligent sootblowing system, at least in this specific boiler. In the economiser, the decline of calculated heat transfer coefficients showed a relative rate of fouling on individual tube banks. The results show that the fouling rate is significantly higher in the top tube banks, which comes first in the direction of the flue gas, compared to downstream banks. Experiments by sootblowing the top tube bank more frequently than the

  15. 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.

  16. Control Properties of Bottom Fired Marine Boilers

    DEFF Research Database (Denmark)

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

    2005-01-01

    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...

  17. 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.

  18. Infrared imaging of fossil fuel power plant boiler interiors

    Science.gov (United States)

    Howard, James W.; Cranton, Brian W.; Armstrong, Karen L.; Hammaker, Robert G.

    1997-08-01

    Fossil fuel power plant boilers operate continuously for months at a time, typically shutting down only for routine maintenance or to address serious equipment failures. These shutdowns are very costly, and diagnostic tools and techniques which could be used to minimize shutdown duration and frequency are highly desirable. Due to the extremely hostile environment in these boilers, few tools exist to inspect and monitor operating boiler interiors. This paper presents the design of a passively cooled, infrared borescope used to inspect the interior of operating boilers. The borescope operates at 3.9 micrometer, where flame is partially transparent. The primary obstacles overcome in the instrument design were the harsh industrial environment surrounding the boilers and the high temperatures encountered inside the boilers. A portable yet durable lens system and enclosure was developed to work with a scanning radiometer to address these two problems by both shielding the radiometer from the environment and by extending the optical train into a snout designed to be inserted into access ports on the sides of the boiler. In this manner, interior images of the boiler can be made while keeping the radiometer safely outside the boiler. The lens views a 40 degree field of view through any 2.5' or larger opening in a foot thick boiler wall. Three of these borescopes have been built, and high resolution images of boiler interiors have been obtained.

  19. Monitoring corrosion rates and localised corrosion in low conductivity water

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    2006-01-01

    Monitoring of low corrosion rates and localised corrosion in a media with low conductivity is a challenge. In municipal district heating, quality control may be improved by implementing on-line corrosion monitoring if a suitable technique can be identified to measure both uniform and localised...... corrosion. Electrochemical techniques (LPR, EIS, crevice corrosion current) as well as direct measurement techniques (high-sensitive electrical resistance, weight loss) have been applied in operating plants. Changes in the corrosion processes are best monitored in non-aggressive, low conductivity media...... with sensitive electrical resistance technique and crevice corrosion current measurements....

  20. Causes and Characteristics for Frequent Tube Blasting of Utility Boiler%电站锅炉热管常见泄漏原因及主要特征

    Institute of Scientific and Technical Information of China (English)

    沈美华; 祝新伟; 潘金平; 程宏辉; 徐卫东

    2013-01-01

    电站锅炉受热面管内外广泛接触烟、火、灰、水、汽、垢等介质,其工作环境恶劣且复杂,经常会因为各种原因而导致爆管泄漏失效的发生,给企业带来巨大的经济损失.详细介绍了磨损、长期过热、短期过热、氢损伤、腐蚀疲劳、氧腐蚀、应力腐蚀、碱性腐蚀以及酸腐蚀9种常见的电站锅炉受热面管的泄漏失效原因及其主要特征,对迅速确定锅炉爆管原因以及提出解决措施,规范锅炉系统的操作等具有重要指导意义.%Heating surface tubes of utility boiler widely contact the media of smoke,fire,ash,water,steam,scale and etc.The tubes,which have wicked and complex working conditions,often blast and result in leakage failure because of many reasons.These bring huge economic losses to the enterprises.Nine kinds of tube blasting reasons and their main representation characters were detailedly introduced.These tube blasting reasons include abrasive erosion,long-term overheating,short term overheating,hydrogen damage,corrosion fatigue,oxygen corrosion,stress corrosion,caustic corrosion and acid corrosion.It has important guiding significance to rapidly ascertain the causes and ultimately resolve the tube blasting problems of the utility boiler and to normalize boiler system operation.

  1. The Boiler Booster design: Feasibility study for an implementation of the Climate Well absorption technology in conventional boilers in order to improve its performance

    OpenAIRE

    Pallarols Farreras, Jordina

    2008-01-01

    European Union has recently made a new directive to impose a classification system based on boilers efficiency. This new regulation generates the necessity of create new boilers more energy efficient like the one developed throughout this thesis. An innovative combined heat and power boiler (CHP boiler) called Boiler Booster is studied in this thesis. The main focus will therefore be to design the Boiler Booster taking the advantage of using the patented absorption technology ...

  2. The Necessity of Small Industrial Boiler Feed Water Deoxidization%小型工业锅炉给水除氧必要性的探讨

    Institute of Scientific and Technical Information of China (English)

    张荣华; 买买提艾力·肉孜

    2015-01-01

    In this paper, the necessity of deoxidization for small pressure hot water and steam boiler(hereinafter referred to as"small boiler”) is proposed. And points out that oxygen treatment for small boiler is one of an important way of water treatment, and also an important issue worth considering. According to the update of standard GB1576 and the requirement of economic operation of the boiler, it is necessary to add small boiler oxygen corrosion protection in water quality monitoring, and the water quality is the basic prerequisite for boiler safe and economic operation. For small boiler, especially for small hot water boiler, deoxidization measures should be taken.%本文提出小型承压热水及蒸汽锅炉(以下简称小型锅炉)给水除氧处理的必要性,并指出除氧处理对于小型锅炉同样是一项重要的水处理方式之一,也是一项值得考虑的重要问题。根据GB1576新老标准的更新与锅炉经济运行的要求,笔者认为重新把小型锅炉除氧防腐工作加入到水质监测工作中是必要的,水质的好坏是锅炉安全、经济运行的基本前提条件。所以,对于小型锅炉、尤其是对于小型热水锅炉应采取除氧措施。

  3. Automated Methods Of Corrosion Measurements

    DEFF Research Database (Denmark)

    Bech-Nielsen, Gregers; Andersen, Jens Enevold Thaulov; Reeve, John Ch;

    1997-01-01

    The chapter describes the following automated measurements: Corrosion Measurements by Titration, Imaging Corrosion by Scanning Probe Microscopy, Critical Pitting Temperature and Application of the Electrochemical Hydrogen Permeation Cell.......The chapter describes the following automated measurements: Corrosion Measurements by Titration, Imaging Corrosion by Scanning Probe Microscopy, Critical Pitting Temperature and Application of the Electrochemical Hydrogen Permeation Cell....

  4. Corrosion Failures in Marine Environment

    Directory of Open Access Journals (Sweden)

    R. Krishnan

    1985-04-01

    Full Text Available This paper gives a brief description of typical marine environments and the most common form of corrosion of materials used in this environment. Some typical case histories of failures pertaining to pitting, bimetallic corrosion, dealloying, cavitation and stress corrosion cracking are illustrated as typical examples of corrosion failures.

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

    Energy Technology Data Exchange (ETDEWEB)

    Mike Bockelie; Marc Cremer; Kevin Davis; Temi Linjewile; Connie Senior; Hong-Shig Shim; Bob Hurt; Eric Eddings; Larry Baxter

    2003-01-30

    This is the tenth 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 NO{sub x} 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. During this quarter, progress was made on the computational simulation of a full-scale boiler with the purpose of understanding the potential impacts of burner operating conditions on soot and NO{sub x} generation. Sulfation tests on both the titania support and vanadia/titania catalysts were completed using BYU's in situ spectroscopy reactor this quarter. These experiments focus on the extent to which vanadia and titania sulfate in an SO{sub 2}-laden, moist environment. Construction of the CCS reactor system is essentially complete and the control hardware and software are largely in place. A large batch of vanadia/titania catalyst in powder form has been prepared for use in poisoning tests. During this quarter, minor modifications were made to the multi-catalyst slipstream reactor and to the control system. The slipstream reactor was installed at AEP's Rockport plant at the end of November 2002. In this report, we describe the reactor system, particularly the control system, which was created by REI specifically for the reactor, as well as the installation at Rockport.

  6. Cladding in the boiler construction and plant engineering. Newest developments; Schweissplattieren im Kessel- und Anlagenbau. Neueste Entwicklungen

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmeister, W. [Uhlig Rohrbogen GmbH, Langelsheim (Germany)

    2007-07-01

    Cladding is a suitable means for the protection of exhaust-subjected surfaces from corrosion and erosion. The author of the contribution under consideration reports on the newest developments with the cladding in the boiler construction and equipment construction. After the description of the historical development of the cladding, the procedure, the practical applications as well as the influence by welding wire, inert gas and welding position are described. A further chapter of this contribution is concerned to the acceptance test and documentation. Innovative applications are described by the example of Tetra Tubes. The concluding chapter is concerned to the CMT technology as a revolution in the joining technology.

  7. The Corrosion and Preservation of Iron Antiques.

    Science.gov (United States)

    Walker, Robert

    1982-01-01

    Discusses general corrosion reactions (iron to rust), including corrosion of iron, sulfur dioxide, chlorides, immersed corrosion, and underground corrosion. Also discusses corrosion inhibition, including corrosion inhibitors (anodic, cathodic, mixed, organic); safe/dangerous inhibitors; and corrosion/inhibition in concrete/marble, showcases/boxes,…

  8. Corrosion resistant amorphous alloys

    International Nuclear Information System (INIS)

    A review of publication data on corrosion resistance of amorphous alloys and the methods of amorphization of surface layers of massive materials (laser treatment, iron implantation, detonation-gas spraying, cathode and ion sputtering, electrodeposition) was made. A study was made on corrosion properties of Fe66Cr11B10Si4 alloy in cast state and after laser irradiation, rendering the surface amorphous as well as the samples of Arenco iron and steel 20 with ion-plasma coatings of Fe-Cr-Ni-Ti alloy. It was established that amorphous coatings posses much higher corrosion resistance as compared to crystalline alloys on the same base

  9. Microbiologically influenced corrosion testing

    International Nuclear Information System (INIS)

    This symposium was held November 16--17, 1992 in Miami, Florida. The purpose of the symposium was to provide a forum for state-of-the-art information on the effects of microorganisms on the corrosion of metals. Many industrial needs in the area of microbial influenced corrosion testing are identified in the presentations along with latest laboratory and field testing techniques. Strategies to monitor and control corrosion and biofouling in water distribution systems, underground pipelines, buildings, and marine vessels are discussed. Individual papers have been processed separately for inclusion in the appropriate data bases

  10. Understanding localized corrosion

    Directory of Open Access Journals (Sweden)

    G.S. Frankel

    2008-10-01

    Full Text Available The breakdown of a protective passive film leading to accelerated dissolution at localized sites is an important practical issue and a vexing scientific problem. The small dimensions, short timescale, and dynamic interplay between a heterogeneous surface and changing potential and solution concentration gradients complicate the development of a complete understanding of the phenomena. This review touches on some of the recent developments in the field, including scanning tunneling microscopy imaging of the earliest stages of pitting which supports a new model explaining the localization of attack, pitting in thin aqueous layers relevant to atmospheric corrosion, the factors controlling crevice corrosion, and predictive modeling of localized corrosion.

  11. Corrosion-resistant uranium

    Science.gov (United States)

    Hovis, V.M. Jr.; Pullen, W.C.; Kollie, T.G.; Bell, R.T.

    1981-10-21

    The present invention is directed to the protecting of uranium and uranium alloy articles from corrosion by providing the surfaces of the articles with a layer of an ion-plated metal selected from aluminum and zinc to a thickness of at least 60 microinches and then converting at least the outer surface of the ion-plated layer of aluminum or zinc to aluminum chromate or zinc chromate. This conversion of the aluminum or zinc to the chromate form considerably enhances the corrosion resistance of the ion plating so as to effectively protect the coated article from corrosion.

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

    Directory of Open Access Journals (Sweden)

    P. M. Glamazdin

    2016-01-01

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

  13. Panel report on corrosion in energy systems

    International Nuclear Information System (INIS)

    Corrosion problems in high-temperature (non aqueous) energy systems, corrosion in aqueous energy systems and institutional problems inhibiting the development of corrosion science and engineering are discussed

  14. The microbial corrosion

    International Nuclear Information System (INIS)

    Underestimated for a long time, corrosion due to microorganisms induces degradation, sometimes fulminant, of a lot of metallic structures in the world. Searchers are using plentiful analytical tools to understand this phenomenon. (O.M.)

  15. Corrosion Inhibitors for Aluminum.

    Science.gov (United States)

    Muller, Bodo

    1995-01-01

    Describes a simple and reliable test method used to investigate the corrosion-inhibiting effects of various chelating agents on aluminum pigments in aqueous alkaline media. The experiments that are presented require no complicated or expensive electronic equipment. (DDR)

  16. Cause analysis and treatment of boiler water abnormity in a 300 MW unit%300 MW热电机组锅炉水质异常分析及处理

    Institute of Scientific and Technical Information of China (English)

    刘玮; 马知敬; 贾蓉

    2014-01-01

    新疆米东热电厂1号机组锅炉炉水电导率和 pH 值较高,超出正常范围,对水冷壁管存在腐蚀的风险。检测发现炉水中出现了大量游离NaOH,分析发现其由作为给水补水的热网疏水受热网循环水的污染所致。由于连续排污扩容器的分离蒸汽至除氧器的逆止阀存在缺陷,造成锅炉未真正有效排污,炉水长期处于过度浓缩状态,最终产生大量游离NaOH,对锅炉加强排污后,炉水水质恢复正常。%The conductivity and pH value of boiler water in No.1 unit of Midong Thermal Power Plant were over standard.So the water wall tubes suffered the risk of alkaline corrosion and boiler water concentrate corrosion.Detection finds a larger number of free sodium hydroxide appears in the boiler water.This is because the heat-supply network drain which is used as the feed water supplement water was polluted by leakage of circulating water of district heating system heater. The check valve between the steam separated from continuous blow-down flash vessel and the de-aerator had some defects,leading to invalid blow down,so the boiler water were over concentrat-ed,a larger number of free sodium hydroxide appeared in the boiler water,resulting in boiler wa-ter abnormality eventually.Finally,after improving continuous blow down,the boiler water turned back to normal.

  17. 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.)

  18. Carbon Dioxide Corrosion:

    DEFF Research Database (Denmark)

    Fosbøl, Philip Loldrup

    2008-01-01

    CO2 corrosion is a general problem in the industry and it is expensive. The focus of this study is an oil gas production related problem. CO2 corrosion is observed in offshore natural gas transportation pipelines. A general overview of the problem is presented in chapter 1. The chemical system...... consists mainly of CO2-Na2CO3-NaHCO3-MEG-H2O. Sodium is injected in the pipelines as NaOH in order to pH-stabilize the pipeline to avoid corrosion and MEG is injected in order to prevent gas hydrates. There are a great number of models available in the literature which may predict CO2 corrosion...... with the basic thermodynamics of electrolytes in chapter 2, the extension and general description of electrolyte mass transport in chapter 3, and the electrochemical kinetics of corrosion in chapter 4. A literature overview of CO2 corrosion is shown in chapter 5 and possible extensions of the models...

  19. Circulating fluidized bed boilers design and operations

    CERN Document Server

    Basu, Prabir

    1991-01-01

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

  20. 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.

  1. 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.

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

    International Nuclear Information System (INIS)

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

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

    DEFF Research Database (Denmark)

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

    2003-01-01

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

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

    DEFF Research Database (Denmark)

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

    2003-01-01

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

  6. 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.

  7. 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.

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

    Science.gov (United States)

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

    2013-09-01

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

  9. Smart aircraft fastener evaluation (SAFE) system: a condition-based corrosion detection system for aging aircraft

    Science.gov (United States)

    Schoess, Jeffrey N.; Seifert, Greg; Paul, Clare A.

    1996-05-01

    The smart aircraft fastener evaluation (SAFE) system is an advanced structural health monitoring effort to detect and characterize corrosion in hidden and inaccessible locations of aircraft structures. Hidden corrosion is the number one logistics problem for the U.S. Air Force, with an estimated maintenance cost of $700M per year in 1990 dollars. The SAFE system incorporates a solid-state electrochemical microsensor and smart sensor electronics in the body of a Hi-Lok aircraft fastener to process and autonomously report corrosion status to aircraft maintenance personnel. The long-term payoff for using SAFE technology will be in predictive maintenance for aging aircraft and rotorcraft systems, fugitive emissions applications such as control valves, chemical pipeline vessels, and industrial boilers. Predictive maintenance capability, service, and repair will replace the current practice of scheduled maintenance to substantially reduce operational costs. A summary of the SAFE concept, laboratory test results, and future field test plans is presented.

  10. Study of the Intercrystalline Corrosion in Pipes of Stainless Steel in a Combined Cycle

    Directory of Open Access Journals (Sweden)

    Raúl Andrés Montejo Serrano

    2014-09-01

    Full Text Available The present work is carried out with the purpose of giving answer to the possible presence ofintercrystalline corrosion and its future consequences in the built tubes of stainless steel 304L anddedicated to the conduction from the water to the boilers of a combined cycle of electricity production.The plant is these in this moments in installation of process investor and assembly and this study wasrequested since during the trial of installation of the pipes of stainless steel that will drive the watertried to the steam generators, they were detected on the part of the operatives some imperfections inthe material, what generated the doubt about the possibility of presence of intercrystalline corrosion orof another type in the pipes. After the realized rehearsals according to international norms and alsousing rehearsals metallography you concludes that the material employee is not sensitive to this typeof corrosion.

  11. Corrosion monitoring in a straw-fired power plant using an electrochemical noise probe

    DEFF Research Database (Denmark)

    Cappeln, Frederik Vilhelm; Bjerrum, Niels; Petrushina, Irina

    2007-01-01

    Electrochemical Noise Measurements have been carried out in situ in a straw-fired power plant using an experimental probe constructed from alumina and AlSl 347 steel. Based on a framework of controlled laboratory experiments it has been found that electrochemical noise has the unique ability to...... provide in-situ monitoring of intergranular corrosion in progress. The probe had a lifetime of two months. It was shown that down-time corrosion in the boiler was negligible. Electrochemical noise data indicated that metal temperatures around 590 degrees C should be avoided as the intergranular corrosion...... is at an increased level at this temperature, most likely because of favorable conditions for molten salt film condensation....

  12. Modelling reinforcement corrosion in concrete

    DEFF Research Database (Denmark)

    Michel, Alexander; Geiker, Mette Rica; Stang, Henrik;

    2012-01-01

    A physio-chemical model for the simulation of reinforcement corrosion in concrete struc-tures was developed. The model allows for simulation of initiation and subsequent propaga-tion of reinforcement corrosion. Corrosion is assumed to be initiated once a defined critical chloride threshold...... is reached causing the formation of anodic and cathodic regions along the reinforcement. Critical chloride thresholds, randomly distributed along the reinforcement sur-face, link the initiation and propagation phase of reinforcement corrosion. To demonstrate the potential use of the developed model......, a numerical example is pre-sented, that illustrates the formation of corrosion cells as well as propagation of corrosion in a reinforced concrete structure....

  13. Condensing gas boilers for energy efficiency and reduction of CO2 and NOx

    International Nuclear Information System (INIS)

    The objectives of the study are: 1) to demonstrate the effectiveness of condensing gas boiler hot water system in reducing energy costs and pollution; 2) to illustrate the importance of marketing this technology to uninformed end users. The development of condensing boilers in the European Community, the materials used, product designs, key performance measures, and the types of applications suited to these products are outlined. Using calculations from a body of work produced by the Chartered Institute of Building Service Engineers in Britain, it is demonstrated how seasonal efficiency differs from combustion efficiency, and how the added capital cost for these boilers may be recovered within an acceptable commercial pay back period from fuel cost savings. Applying current NOx and CO2 information from a body of the CE Technical Committees, the author show how these products can reduce pollution levels both from CO2 and NOx. An example of marketing these products to a largely uninformed end user customer market is cited. 2 refs., 3 tabs., 12 figs. (orig.)

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

    OpenAIRE

    Jensen, Peter Arendt

    2015-01-01

    While fluid bed and grate fired boilers initially was the choice of boilers used for power production from both wood and herbaceous biomass, in recent years suspension fired boilers have been increasingly used for biomass based power production. In Denmark several large pulverized fuel boilers have been converted from coal to biomass combustion in the last 15 years. This have included co-firing of coal and straw, up to 100% firing of wood or straw andthe use of coal ash as an additive to reme...

  15. Relocation of boilers to Gulbene, Latvia. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-01

    This report describes the relocation of two coal-fired boilers from Hoeje-Taastrup, Denmark to the City of Gulbene, Latvia and the conversion of one of these boilers to combustion of wood chips. The selection of Gulbene DHE as recipient of the two boilers was made by the Danish Energy Agency. The selection was based on e feasibility study, `Small Boilers Fuel Conversion Study` prepared by the Consulting Engineering Company Birch and Krogeoe/Esbensen in 1994. The recommendations regarding the relocation and conversion of the former coal-fired boilers to use wood chips have been given in a study performed by dk-TEKNIK in the year 1994. The objectives of the Consultant`s project can be summarized as follows: Prequalification of Contractors for the boiler relocation; Preparation of Tender Documents for relocation of two formerly coal-fired boilers placed in Hoeje-Taastrup to Gulbene and conversion of the boilers to combustion of wood fuel; Evaluation and Contracting; Site supervision; Handing-over. The scope of the report describes the final reporting of the boiler relocation to Gulbene. This includes: The process of the relocation; Financial calculations; Experience gained through the project. (EG)

  16. 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.

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

    Science.gov (United States)

    2010-10-01

    ... ENGINEERING POWER BOILERS Requirements for Firetube Boilers § 52.20-17 Opening between boiler and safety valve (modifies PFT-44). When a discharge pipe is used, it must be installed in accordance with the...

  18. Coal Ash Corrosion Resistant Materials Testing

    Energy Technology Data Exchange (ETDEWEB)

    D. K. McDonald; P. L. Daniel; D. J. DeVault

    2007-12-31

    In April 1999, three identical superheater test sections were installed into the Niles Unit No.1 for the purpose of testing and ranking the coal ash corrosion resistance of candidate superheater alloys. The Niles boiler burns high sulfur coal (3% to 3.5%) that has a moderate alkali content (0.2% sodium equivalents), thus the constituents necessary for coal ash corrosion are present in the ash. The test sections were controlled to operate with an average surface metal temperature from approximately 1060 F to 1210 F which was within the temperature range over which coal ash corrosion occurs. Thus, this combination of aggressive environment and high temperature was appropriate for testing the performance of candidate corrosion-resistant tube materials. Analyses of the deposit and scale confirmed that aggressive alkali sulfate constituents were present at the metal surface and active in tube metal wastage. The test sections were constructed so that the response of twelve different candidate tube and/or coating materials could be studied. The plan was to remove and evaluate one of the three test sections at time intervals of 1 year, 3 years, and 5 years. This would permit an assessment of performance of the candidate materials as a function of time. Test Section A was removed in November 2001 after about 24 months of service at the desired steam temperature set point, with about 15.5 months of exposure at full temperature. A progress report, issued in October 2002, was written to document the performance of the candidate alloys in that test section. The evaluation described the condition of each tube sample after exposure. It involved a determination of the rate of wall thickness loss for these samples. In cases where there was more than one sample of a candidate material in the test section, an assessment was made of the performance of the alloy as a function of temperature. Test Sections B and C were examined during the November 2001 outage, and it was decided that

  19. Preparation and Corrosion Resistance of Rare Earth Ceramic Film on AZ91 Magnesium Alloy

    Institute of Scientific and Technical Information of China (English)

    Xu Yue; Guo Yuandong; Li Yingjie

    2004-01-01

    With the purpose of improving corrosion resistance and solving environmental pollution caused by traditional protective technique, rare earth ceramic film on AZ91 magnesium alloy was prepared by dip coating process, and technical parameters of preparation were defmed. Microstructure and composition of the film were studied and corrosion resistance was evaluated as well. The results show that rare earth ceramic film is uniform,dense, with strong cohesion and intact coverage. The film is mainly made up of CeO2 and MgCeO3. The results of corrosion experiments approve that the film acts as a barrier to isolate the contact of the substrate with corrosion media and decreas corrosion rate. Polarization curve of the coated sample shiftes to positive potential obvito 2.7 × 104 Ω. These facts indicate that rare earth ceramic film could effectively improve corrosion resistance of AZ91 magnesium alloy.

  20. Corrosion of iron by sulfate-reducing bacteria: new views of an old problem.

    Science.gov (United States)

    Enning, Dennis; Garrelfs, Julia

    2014-02-01

    About a century ago, researchers first recognized a connection between the activity of environmental microorganisms and cases of anaerobic iron corrosion. Since then, such microbially influenced corrosion (MIC) has gained prominence and its technical and economic implications are now widely recognized. Under anoxic conditions (e.g., in oil and gas pipelines), sulfate-reducing bacteria (SRB) are commonly considered the main culprits of MIC. This perception largely stems from three recurrent observations. First, anoxic sulfate-rich environments (e.g., anoxic seawater) are particularly corrosive. Second, SRB and their characteristic corrosion product iron sulfide are ubiquitously associated with anaerobic corrosion damage, and third, no other physiological group produces comparably severe corrosion damage in laboratory-grown pure cultures. However, there remain many open questions as to the underlying mechanisms and their relative contributions to corrosion. On the one hand, SRB damage iron constructions indirectly through a corrosive chemical agent, hydrogen sulfide, formed by the organisms as a dissimilatory product from sulfate reduction with organic compounds or hydrogen ("chemical microbially influenced corrosion"; CMIC). On the other hand, certain SRB can also attack iron via withdrawal of electrons ("electrical microbially influenced corrosion"; EMIC), viz., directly by metabolic coupling. Corrosion of iron by SRB is typically associated with the formation of iron sulfides (FeS) which, paradoxically, may reduce corrosion in some cases while they increase it in others. This brief review traces the historical twists in the perception of SRB-induced corrosion, considering the presently most plausible explanations as well as possible early misconceptions in the understanding of severe corrosion in anoxic, sulfate-rich environments.

  1. Corrosion testing using isotopes

    Science.gov (United States)

    Hohorst, Frederick A.

    1995-12-05

    A method for determining the corrosion behavior of a material with respect to a medium in contact with the material by: implanting a substantially chemically inert gas in a matrix so that corrosion experienced by the material causes the inert gas to enter the medium; placing the medium in contact with the material; and measuring the amount of inert gas which enters the medium. A test sample of a material whose resistance to corrosion by a medium is to be tested, composed of: a body of the material, which body has a surface to be contacted by the medium; and a substantially chemically inert gas implanted into the body to a depth below the surface. A test sample of a material whose resistance to corrosion by a medium is to be tested, composed of: a substrate of material which is easily corroded by the medium, the substrate having a surface; a substantially chemically inert gas implanted into the substrate; and a sheet of the material whose resistance to corrosion is to be tested, the sheet being disposed against the surface of the substrate and having a defined thickness.

  2. Operation related on-line measurements of low temperature fire side corrosion during co-combustion of biomass and oil; Driftrelaterad direktmaetning av laagtemperaturkorrosion i en braensleeldad kraftvaermeanlaeggning

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, Thomas [Studsvik Nuclear AB, Nykoeping (Sweden)

    2000-05-01

    A number of combustion plants have experienced corrosion attack on air preheaters and economisers when fired with biomass fuels. In certain plants the problems are great and reconstruction has been performed so that exposed components can be exchanged during operation. The electrochemical techniques offer on-line measurements of the changes in corrosion rate in the low temperature region in a waste incinerator. The purpose with this study was to evaluate the technique in a biomass fired boiler where the corrosion rate is considerable lower compared to a waste incinerator. Experiments were performed at the Haesselby plant, boiler 3, which was fired with pure biomass as well as a mixture of biomass and oil during the test period. It was found that the electrochemical technique is a useful tool for on-line measurements of the changes in corrosion rate in biomass fired utilities. Since the corrosion rate in the low temperature region is dependent on the boiler construction, electrochemical measurements give valuable information on the corrosion rate during optimisation of the fuel mixture, SNCR and temperature or the low temperature components. This is of special importance when introducing new fuels or fuel mixtures. Soot blowing is of prime importance for the total corrosion. During a few minutes an individual soot blower can initiate such a high corrosion rate that it represents the total corrosion. The material temperature is another important parameter. Above a certain temperature the corrosion rate is negligible. During co-combustion this temperature was found to be in the region 65-85 deg C. The influence of the SNCR with ammonia, with respect to corrosion, is dependent on the fuel mixture used. In utilities where acidic combustion products are formed, ammonia has a neutralising effect e.g. in Hoegdalen. At the Haesselby plant this neutralising effect was not found. During cocombustion with oil the ammonia forms ammoniahydrosulphate which increases the corrosion

  3. Superheater material test in Vaestervik municipal waste fired boiler with mobile probes; Prov av oeverhettarmaterial i Vaesterviks avfallspanna med mobila maetsonder

    Energy Technology Data Exchange (ETDEWEB)

    Roennquist, E.M. [Sydkraft Konsult AB (Sweden)

    1998-09-01

    The aim was to test material probes in a waste incineration boiler where they are subjected to a similar environment as a superheater and evaluate the tested material. The waste incineration boiler at Vaestervik is a 10 MW bubbling fluidized bed boiler. The boiler is fired with municipal waste mixed with some industrial waste. The probes were installed high up in the second draft. Two probes were operated at a constant temperature (467 and 527 deg C respectively) and one probe with a temperature gradient of 150 deg C. The testing time was about 1000 h. The boiler was operated intermittent, often with several shut downs per day. Meanwhile it was normally run with full capacity. The composition of the fuel and flue gas were measured. The Cl content in the corrosion environment of the waste incineration boiler is important. For the most attacked samples the metal loss was almost 3 mm/1000 h, which is considered as very high. The high metal loss may be partly explained by the many shut downs. The metal loss increases as the temperature is increased. This can be seen on all the probes. The probes with constant temperature show similar metal loss independent of sample position. It is possible to rank the materials in three groups. The highest metal loss was found for the ferritic steels 13CrMo44 and X20. The intermediate metal loss for the austenitic steels 3R12 and 3RE28. Also the Fe-Cr-Ni alloy Sanicro 28 show intermediate metal loss. The lowest metal loss was found for the nickel base alloys Alloy 625 and Sanicro 65 Figures and tables with text in English. 6 refs, 16 figs, 12 tabs, 55 appendixes

  4. Severe Environmental Corrosion Erosion Facility

    Data.gov (United States)

    Federal Laboratory Consortium — NETL’s Severe Environment Corrosion Erosion Facility in Albany, OR, allows researchers to safely examine the performance of materials in highly corrosive or erosive...

  5. Microbial Corrosion: 1988 Workshop Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    None

    1989-04-01

    Microbial action can greatly increase corrosion damage in power plant water systems. This workshop pulled together practical experience and theoretical knowledge on microbially induced corrosion, documented diagnostic and treatment methods, and identified areas for future research.

  6. Corrosion-resistant metal surfaces

    Science.gov (United States)

    Sugama, Toshifumi

    2009-03-24

    The present invention relates to metal surfaces having thereon an ultrathin (e.g., less than ten nanometer thickness) corrosion-resistant film, thereby rendering the metal surfaces corrosion-resistant. The corrosion-resistant film includes an at least partially crosslinked amido-functionalized silanol component in combination with rare-earth metal oxide nanoparticles. The invention also relates to methods for producing such corrosion-resistant films.

  7. Atmospheric corrosion of mild steel

    OpenAIRE

    Morcillo, Manuel; Fuente, Daniel de la; Díaz Ocaña, Iván; Cano, Heidis

    2011-01-01

    The atmospheric corrosion of mild steel is an extensive topic that has been studied by many authors in different regions throughout the world. This compilation paper incorporates relevant publications on the subject, in particular about the nature of atmospheric corrosion products, mechanisms of atmospheric corrosion and kinetics of the atmospheric corrosion process, paying special attention to two matters upon which relatively less information has been published: a) the morpholog...

  8. Atmospheric corrosion of mild steel

    OpenAIRE

    Morcillo, M.; de la Fuente, D.; I. Díaz; Cano, H.

    2011-01-01

    The atmospheric corrosion of mild steel is an extensive topic that has been studied by many authors in different regions throughout the world. This compilation paper incorporates relevant publications on the subject, in particular about the nature of atmospheric corrosion products, mechanisms of atmospheric corrosion and kinetics of the atmospheric corrosion process, paying special attention to two matters upon which relatively less information has been published: a) the morphology of steel c...

  9. Plastics for corrosion inhibition

    CERN Document Server

    Goldade, Victor A; Makarevich, Anna V; Kestelman, Vladimir N

    2005-01-01

    The development of polymer composites containing inhibitors of metal corrosion is an important endeavour in modern materials science and technology. Corrosion inhibitors can be located in a polymer matrix in the solid, liquid or gaseous phase. This book details the thermodynamic principles for selecting these components, their compatibility and their effectiveness. The various mechanisms of metal protection – barrier, inhibiting and electromechanical – are considered, as are the conflicting requirements placed on the structure of the combined material. Two main classes of inhibited materials (structural and films/coatings) are described in detail. Examples are given of structural plastics used in friction units subjected to mechano-chemical wear and of polymer films/coatings for protecting metal objects against corrosion.

  10. Potential applications of renewable energy sources, biomass combustion problems in boiler power systems and combustion related environmental issues

    International Nuclear Information System (INIS)

    This paper describes the potential applications of renewable energy sources to replace fossil fuel combustion as the prime energy sources in various countries, and discusses problems associated with biomass combustion in boiler power systems. Here, the term biomass includes organic matter produced as a result of photosynthesis as well as municipal, industrial and animal waste material. Brief summaries of the basic concepts involved in the combustion of biomass fuels are presented. Renewable energy sources (RES) supply 14% of the total world energy demand. RES are biomass, hydropower, geothermal, solar, wind and marine energies. The renewables are the primary, domestic and clean or inexhaustible energy resources. The percentage share of biomass was 62.1% of total renewable energy sources in 1995. Experimental results for a large variety of biomass fuels and conditions are presented. Numerical studies are also discussed. Biomass is an attractive renewable fuel in utility boilers. The compositions of biomass among fuel types are variable. Ash composition for the biomass is fundamentally different from ash composition for the coal. Especially inorganic constituents cause to critical problems of toxic emissions, fouling and slagging. Metals in ash, in combination with other fuel elements such as silica and sulfur, and facilitated by the presence of chlorine, are responsible for many undesirable reactions in combustion furnaces and power boilers. Elements including K, Na, S, Cl, P, Ca, Mg, Fe, Si are involved in reactions leading to ash fouling and slagging in biomass combustors. Chlorine in the biomass may affect operation by corrosion. Ash deposits reduce heat transfer and may also result in severe corrosion at high temperatures. Other influences of biomass composition are observed for the rates of combustion and pollutant emissions. Biomass combustion systems are non-polluting and offer significant protection of the environment. The reduction of greenhouse gases

  11. Corrosion resistant PEM fuel cell

    Science.gov (United States)

    Fronk, Matthew Howard; Borup, Rodney Lynn; Hulett, Jay S.; Brady, Brian K.; Cunningham, Kevin M.

    2002-01-01

    A PEM fuel cell having electrical contact elements comprising a corrosion-susceptible substrate metal coated with an electrically conductive, corrosion-resistant polymer containing a plurality of electrically conductive, corrosion-resistant filler particles. The substrate may have an oxidizable metal first layer (e.g., stainless steel) underlying the polymer coating.

  12. CFD modeling of a boiler's tubes rupture

    International Nuclear Information System (INIS)

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

  13. Nuclear reactors with auxiliary boiler circuit

    International Nuclear Information System (INIS)

    A gas-cooled nuclear reactor has a main circulatory system for the gaseous coolant incorporating one or more main energy converting units, such as gas turbines, and an auxiliary circulatory system for the gaseous coolant incorporating at least one steam generating boiler arranged to be heated by the coolant after its passage through the reactor core to provide steam for driving an auxiliary steam turbine, such an arrangement providing a simplified start-up procedure also providing emergency duties associated with long term heat removal on reactor shut down

  14. 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...... showed substantial improvement compared to a decentralized scheme based on sequential loop closing. Similar or better result is expected to be obtainable using a full Multiple input Multiple output scheme. Furthermore closed loop simulations, applying a linear controller to the nonlinear plant model...... on states and control signals should be considered....

  15. 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...

  16. 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.

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

    International Nuclear Information System (INIS)

    This paper begins with a brief review on the similarity law of conventional fossil-fuel-fired boilers. The concept is based on the fact that the heat release due to combustion in the furnace is restricted by the furnace volume but the heat absorption is restricted by the heat transfer surface area. This means that a small-capacity boiler has relatively high specific furnace heat release rate, about 10 MW/m3, and on the contrary a large-capacity boiler has lower value. The surface-heat-flux limit is mainly dominated by the CHF inside the water-wall tubes of the boiler furnace, about 350 kW/m2. This heat-flux limit is almost the same order independently on the capacity of boilers. For the safety of water-walls, it is essential to retain suitable water circulation, i.e. circulation ratio and velocity of water. This principle is a common knowledge of boiler designer, but actual situation is not the case. Newly designed boilers often suffer from similar accidents, especially burnout due to circulation problems. This paper demonstrates recent accidents encountered in practical boilers, and raises problems of rather classical but important two-phase flow and heat transfer. (author)

  18. 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....

  19. 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.

  20. 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) Pressure vessels must be tested and inspected in accordance with part 61, subpart 61.10, of this...

  1. 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...

  2. Quality assurance in fabrication of boilers and pressure vessels

    International Nuclear Information System (INIS)

    Quality assurance for safety and reliability of boilers and pressure vessels is a systematic approach involving various stages right from material identification to final stages of testing, transportation and storage before commissioning. This paper brings out various quality . Assurance aspects to be implemented by manufacturers of boilers and pressure vessels. 1 fig

  3. 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...

  4. 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...

  5. 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...

  6. Thermomechanical finite element analysis of hot water boiler structure

    Directory of Open Access Journals (Sweden)

    Živković Dragoljub S.

    2012-01-01

    Full Text Available The paper presents an application of the Finite Elements Method for stress and strain analysis of the hot water boiler structure. The aim of the research was to investigate the influence of the boiler scale on the thermal stresses and strains of the structure of hot water boilers. Results show that maximum thermal stresses appear in the zone of the pipe carrying wall of the first reversing chamber. This indicates that the most critical part of the boiler are weld spots of the smoke pipes and pipe carrying plate, which in the case of significant scale deposits can lead to cracks in the welds and water leakage from the boiler. The nonlinear effects were taken into account by defining the bilinear isotropic hardening model for all boiler elements. Temperature dependency was defined for all relevant material properties, i. e. isotropic coefficient of thermal expansion, Young’s modulus, and isotropic thermal conductivity. The verification of the FEA model was performed by comparing the measured deformations of the hot water boiler with the simulation results. As a reference object, a Viessmann - Vitomax 200 HW boiler was used, with the installed power of 18.2 MW. CAD modeling was done within the Autodesk Inventor, and stress and strain analysis was performed in the ANSYS Software.

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

    Science.gov (United States)

    2010-10-01

    ... drum type exhaust gas steam boiler must have a feed water control system. The system must automatically... 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...

  8. Corrosion inhibition in the presence of microbial corrosion

    Energy Technology Data Exchange (ETDEWEB)

    Videla, H.A. [Univ. of La Plata (Argentina). Dept. of Chemistry

    1996-12-01

    Microorganisms influence corrosion by changing the electrochemical conditions at the metal/solution interface. These changes may have different effects, ranging from the induction of localized corrosion to corrosion inhibition. The key to the alteration of conditions at a metal surface and hence, the enhancement or inhibition of corrosion is the formation of a biofilm. On a biologically conditioned metal surface microorganisms can induce corrosion inhibition in several ways: (a) by neutralizing the action of a corrosive substance already present in the medium; (b) by stabilizing a protective film on a metal surface or (c) by inducing a decrease in the medium aggressiveness. Seldomly mentioned in the literature, microbial inhibition of corrosion could be a potentially useful tool to counteract many of the biodeterioration cases encountered in practice.

  9. Alkali deposits found in biomass boilers: The behavior of inorganic material in biomass-fired power boilers -- Field and laboratory experiences. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, L.L. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility; Miles, T.R.; Miles, T.R. Jr. [Miles (Thomas R.), Portland, OR (United States); Jenkins, B.M. [California Univ., Davis, CA (United States); Dayton, D.C.; Milne, T.A. [National Renewable Energy Lab., Golden, CO (United States); Bryers, R.W. [Foster Wheeler Development Corp., Livingston, NJ (United States); Oden, L.L. [Bureau of Mines, Albany, OR (United States). Albany Research Center

    1996-03-01

    This report documents the major findings of the Alkali Deposits Investigation, a collaborative effort to understand the causes of unmanageable ash deposits in biomass-fired electric power boilers. Volume 1 of this report provide an overview of the project, with selected highlights. This volume provides more detail and discussion of the data and implications. This document includes six sections. The first, the introduction, provides the motivation, context, and focus for the investigation. The remaining sections discuss fuel properties, bench-scale combustion tests, a framework for considering ash deposition processes, pilot-scale tests of biomass fuels, and field tests in commercially operating biomass power generation stations. Detailed chemical analyses of eleven biomass fuels representing a broad cross-section of commercially available fuels reveal their properties that relate to ash deposition tendencies. The fuels fall into three broad categories: (1) straws and grasses (herbaceous materials); (2) pits, shells, hulls and other agricultural byproducts of a generally ligneous nature; and (3) woods and waste fuels of commercial interest. This report presents a systematic and reasonably detailed analysis of fuel property, operating condition, and boiler design issues that dictate ash deposit formation and property development. The span of investigations from bench-top experiments to commercial operation and observations including both practical illustrations and theoretical background provide a self-consistent and reasonably robust basis to understand the qualitative nature of ash deposit formation in biomass boilers. While there remain many quantitative details to be pursued, this project encapsulates essentially all of the conceptual aspects of the issue. It provides a basis for understanding and potentially resolving the technical and environmental issues associated with ash deposition during biomass combustion. 81 refs., 124 figs., 76 tabs.

  10. 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.)

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

    DEFF Research Database (Denmark)

    Jensen, Peter Arendt

    formation in suspension fired boilers. The presentation provides an overview of the knowledge obtained with respect to ash species behavior insuspension fired biomass boilers. A mechanistic understanding of the fly ash formation process in biomass fired PF boilers isobtained today. A high fraction of alkali...... salt species are released to the gas phase during the initial fuel combustion process. The salt species are present in gas phase in the boil chamberand upon cooling in the convective pass aerosols are formed. Recent studies indicates that a large fraction of the residual condensed phase ash fragments...... to generate ash particles typically in the size range of 50 to 200 μm on biomass suspension fired power plant boilers. A fragmentation rate of fuel particles of 3 have been used to describe both the residual ash formation process in laboratory entrained flow reactors and in full scale boilers.A range...

  12. Thermographic detection and quantitative characterization of corrosion by application of thermal line source

    Science.gov (United States)

    Cramer, K. Elliott; Winfree, William P.; Reid, Dan; Johnson, Jane

    1999-02-01

    Wall thinning in utility boiler waterwall tubing is a significant inspection concern for boiler operators. Historically, conventional ultrasonics has been used for inspection of these tubes. This technique has proved to be very labor intensive and slow. This has resulted in a `spot check' approach to inspections, making thickness measurements over a relatively small percentage of the total boiler wall area. NASA Langley Research Center has developed a thermal NDE technique designed to image and quantitatively characterize the amount of material thinning present in steel 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 this analysis technique, represents a significant improvement in the inspection speed for large structures such as boiler waterwalls while still providing high-resolution thickness measurements. A theoretical basis for the technique will be presented thus demonstrating the quantitative nature of the technique. Further, results of laboratory experiments on flat panel specimens with fabricated material loss regions will be presented to demonstrate the capabilities of the technique. Additionally, the results of applying this technology to actual waterwall tubing samples will be presented.

  13. Positive grid corrosion elongation analysis using CAE with corrosion deformation transformed into thermal phenomenon

    Science.gov (United States)

    Mukaitani, Ichiroh; Hayashi, Koji; Shimoura, Ichiro; Takemasa, Arihiko; Takahashi, Isamu; Tsubakino, Harushige

    software " Solid Works" and computer aided engineering (CAE) software " ANSYS" with corrosion elongation transformed into thermal elongation. We established a current collector corrosion elongation forecast and found that the microstructure controlled the Pb-Ca-Sn alloy; thus newly designed VRLA batteries (MU-series [A. Takemasa, I. Mukaitani, Y. Yoshiyama, K. Fukui, T. Sakamoto, T. Kuwano, M. Fukuda, H. Misaki, K. Uwatari, Shin-Kobe Technical Report 9 (1999) 11] for telecommunication and LL-series [H. Takabayashi, T. Shibahara, Y. Mastuda, K. Fukui, S. Hazui, Y. Matsumura, S. Kondo, Shin-Kobe Tech. Rep. 11 (2001) 35] for electric energy storage) which are lightweight and have long life are introduced here.

  14. Corrosion in seawater systems

    International Nuclear Information System (INIS)

    Highly alloyed stainless steels have been exposed to natural chlorinated and chlorine-free seawater at 35 deg. C. Simulated tube-tubesheet joints, weld joints and galvanic couples with titanium, 90/10 CuNi and NiAl bronze were tested and evaluated for corrosion. The corrosion rates of various anode materials - zinc, aluminium and soft iron - were also determined. Finally the risk of hydrogen embrittlement of tubes of ferritic stainless steels and titanium as a consequence of cathodic protection was studied. An attempt was also made to explain the cracking mechanism of the ferritic steels by means of transmission electron microscopy. One important conclusion of the project is that chlorinated seawater is considerably more corrosive to stainless steels than chlorine-free water, whereas chlorination reduces the rate of galvanic corrosion of copper materials coupled to stainless steels. Hydrogen embrittlement of ferritic stainless steels and titanium as a consequence of cathodic protection of carbon steel or cast iron in the same structure can be avoided by strict potentiostatic control of the applied potential. (author)

  15. Corrosion protection by anaerobiosis.

    Science.gov (United States)

    Volkland, H P; Harms, H; Wanner; Zehnder, A J

    2001-01-01

    Biofilm-forming bacteria can protect mild (unalloyed) steel from corrosion. Mild steel coupons incubated with Rhodoccocus sp. strain C125 and Pseudomonas putida mt2 in an aerobic phosphate-buffered medium containing benzoate as carbon and energy source, underwent a surface reaction leading to the formation of a corrosion-inhibiting vivianite layer [Fe3(PO4)2]. Electrochemical potential (E) measurements allowed us to follow the buildup of the vivianite cover. The presence of sufficient metabolically active bacteria at the steel surface resulted in an E decrease to -510 mV, the potential of free iron, and a continuous release of ferrous iron. Part of the dissolved iron precipitated as vivianite in a compact layer of two to three microns in thickness. This layer prevented corrosion of mild steel for over two weeks, even in a highly corrosive medium. A concentration of 20 mM phosphate in the medium was found to be a prerequisite for the formation of the vivianite layer.

  16. Passivity and corrosion of special metals

    International Nuclear Information System (INIS)

    The corrosion stability of the metals Zr and Ta and some Ti-alloys was investigated under the conditions of the Purex-process. In addition to classical methods new corrosion-tests and simulations of technical conditions were developed. Further a laser-microprobe analysis is described. While Ta is stable at all conditions Zr shows decreasing corrosion stability with increasing nitric acid-concentration and temperature during potentiodynamic tests. Electrode modifications which are important for the Purex-process were checked. It is the first time that the stability of passive films against radiation is treated fundamentally. α-radiation and hot atoms can be simulated by ion-implantation. In general an amorphisation takes place which makes the layer more flexible and therefore more stable against mechanical stresses. Further the enhancement of electronic conductivity stabilises the favourable potential region between 0-1 V. Electronic processes can be simulated by focussed laser-radiation which induces the growth of additional oxide. The dissolution of oxide films of Ta and Ti is investigated by analysis and electrochemical measurements and is discussed with reference to decontamination processes. (orig.) With 61 refs., 15 tabs., 87 figs., and abstracts of 17 publications in annex

  17. 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.

  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

    2004-10-30

    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.

  19. 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.

  20. 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.