Classification of pulverized coal ash

International Nuclear Information System (INIS)

Van der Sloot, H.A.; Van der Hoek, E.E.; De Groot, G.J.; Comans, R.N.J.

1992-09-01

The leachability of fifty different pulverized coal ashes from utilities in the Netherlands, Federal Republic of Germany and Belgium has been studied. Five different ashes were analyzed according to the complete standard leaching test and the results were published earlier. The examination of a wide variety of ashes under a wide range of pH and Liquid to Solid ratio (LS) conditions creates the possibility of identifying systematic trends in fly ash leaching behaviour and to identify the mechanisms controlling release. 16 figs., 2 tabs., 3 app., 25 refs

Imulation of temperature field in swirl pulverized coal boiler

Science.gov (United States)

Lv, Wei; Wu, Weifeng; Chen, Chen; Chen, Weifeng; Qi, Guoli; Zhang, Songsong

2018-02-01

In order to achieve the goal of energy saving and emission reduction and energy efficient utilization, taking a 58MW swirl pulverized coal boiler as the research object, the three-dimensional model of the rotor is established. According to the principle of CFD, basic assumptions and boundary conditions are selected, the temperature field in the furnace of 6 kinds of working conditions is numerically solved, and the temperature distribution in the furnace is analyzed. The calculation results show that the temperature of the working condition 1 is in good agreement with the experimental data, and the error is less than 10%,the results provide a theoretical basis for the following calculation. Through the comparison of the results of the 6 conditions, it is found that the working condition 3 is the best operating condition of the pulverized coal boiler.

Amphiphilic semi-interpenetrating polymer networks using pulverized rubber

Science.gov (United States)

Shahidi, Nima

Scrap rubber materials provide a significant challenge to either reuse or safe disposal. Every year, millions of tires are discarded to landfills in the United States, consuming a staggering amount of land space, creating a high risk for large fires, breeding mosquitoes that spread diseases, and wasting the planet's natural resources. This situation cannot be sustained. The challenge of reusing scrap rubber materials is mainly due to the crosslinked structure of vulcanized rubber that prevent them from melting and further processing for reuse. The most feasible recycling approach is believed to be a process in which the vulcanized rubber is first pulverized into a fine powder and then incorporated into new products. The production of fine rubber particles is generally accomplished through the use of a cryogenic process that is costly. Therefore, development of a cost effective technology that utilizes a large quantity of the scrap rubber materials to produce high value added materials is an essential element in maintaining a sustainable solution to rubber recycling. In this research, a cost effective pulverization process, solid state shear extrusion (SSSE), was modified and used for continuous pulverization of the rubber into fine particles. In the modified SSSE process, pulverization takes place at high compressive shear forces and a controlled temperature. Furthermore, an innovative particle modification process was developed to enhance the chemical structure and surface properties of the rubber particles for manufacturing of high value added products. Modification of rubber particles was accomplished through the polymerization of a hydrophilic monomer mixture within the intermolecular structure of the hydrophobic rubber particles. The resulting composite particles are considered as amphiphilic particulate phase semi-interpenetrating polymer networks (PPSIPNs). The modified rubber particles are water dispersible and suitable for use in a variety of aqueous media

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

Energy Technology Data Exchange (ETDEWEB)

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

2005-07-01

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

NO emission characteristics of superfine pulverized coal combustion in the O2/CO2 atmosphere

International Nuclear Information System (INIS)

Liu, Jiaxun; Gao, Shan; Jiang, Xiumin; Shen, Jun; Zhang, Hai

2014-01-01

Highlights: • Superfine pulverized coal combustion in O 2 /CO 2 atmosphere is a new promising technology. • NO emissions of superfine pulverized coal combustion in O 2 /CO 2 mixture were focused. • Coal particle sizes have significant effects on NO emissions in O 2 /CO 2 combustion. - Abstract: The combination of O 2 /CO 2 combustion and superfine pulverized coal combustion technology can make full use of their respective merits, and solve certain inherent disadvantages of each technology. The technology of superfine pulverized coal combustion in the O 2 /CO 2 atmosphere is easy and feasible to be retrofitted with few reconstructions on the existing devices. It will become a useful and promising method in the future. In this paper, a one-dimensional drop-tube furnace system was adopted to study the NO emission characteristics of superfine pulverized coal combustion in the O 2 /CO 2 atmosphere. The effects of coal particle size, coal quality, furnace temperature, stoichiometric ratio, etc. were analyzed. It is important to note that coal particle sizes have significant influence on NO emissions in the O 2 /CO 2 combustion. For the homogeneous NO reduction, smaller coal particles can inhibit the homogeneous NO formations under fuel-rich combustion conditions, while it becomes disadvantageous for fuel-lean combustion. However, under any conditions, heterogeneous reduction is always more significant for smaller coal particle sizes, which have smoother pore surfaces and simpler pore structures. The results from this fundamental research will provide technical support for better understanding and developing this new combustion process

Mercury emissions from polish pulverized coalfired boiler

Directory of Open Access Journals (Sweden)

Wichliński Michał

2017-01-01

Full Text Available The current paper presents the research results carried out at one of Polish power plants at a pulverized hard coal-fired 225 MW unit. The research was carried out at full load of the boiler (100% MCR and focused on analysis of mercury content in the input fuel and limestone sorbent for wet flue gas desulfurization (FGD system, as well as investigation of mercury content in the combustion products, i.e. fly ash, slag, FGD product (gypsum and FGD effluents (waste. Within the framework of the present study the concentration of mercury vapor in the exhaust gas was also investigated. The analysis was performed using Lumex RA-915+ spectrometer with an attachment (RP-91C. The measurements were carried out at three locations, i.e. before the electrostatic precipitator (ESP, downstream the ESP, and downstream the wet FGD plant. Design of the measurement system allowed to determine both forms of mercury in the flue gas (Hg0 and Hg2+ at all measurement locations.Based on the measurement results the balance of mercury for a pulverized coal (PC boiler was calculated and the amount of mercury was assessed both in the input solids (fuel and sorbent, as well as the gaseous and solids products (flue gas, slag, ash, gypsum and FGD waste.

Combustion characteristics and kinetic analysis of pulverized coal under different pressure grades

Directory of Open Access Journals (Sweden)

Qiwei ZUO

2016-02-01

Full Text Available By using thermo gravimetric balance, experimental research on combustion characteristics and dynamics parameters of the typical coal injection from some domestic steelworks are conducted with non-isothermal method. The combustion characteristic parameters of the sample pulverized coal such as ignition temperature, peak temperature at maximum weight loss rate, burnout temperature, general burn exponent(S, and maximum combustion rate are studied under pressure grades of 0.1, 1.1, 2.1, 3.1 and 4.1 MPa, the activation energy (E and pre-exponential factor in the combustion process are calculated. The results show that when the pressure increases from 0.1 to 4.1 MPa, ignition temperature decreases by 85.7 K at most, peak temperature at maximum weight loss rate decreases by 249.3 K at most, burnout temperature decreases by 375 K at most, maximum weight loss rate increases by 10 times, and S increases by 33.6 times at most. It is also shown that there exists a kinetic complementation between E and ln A from the view point of dynamics, and the critical pressure of pulverized coal reaction control requirement and combustion mode transform is 3.1 MPa for the pulverized coal.

pulver: an R package for parallel ultra-rapid p-value computation for linear regression interaction terms.

Science.gov (United States)

Molnos, Sophie; Baumbach, Clemens; Wahl, Simone; Müller-Nurasyid, Martina; Strauch, Konstantin; Wang-Sattler, Rui; Waldenberger, Melanie; Meitinger, Thomas; Adamski, Jerzy; Kastenmüller, Gabi; Suhre, Karsten; Peters, Annette; Grallert, Harald; Theis, Fabian J; Gieger, Christian

2017-09-29

Genome-wide association studies allow us to understand the genetics of complex diseases. Human metabolism provides information about the disease-causing mechanisms, so it is usual to investigate the associations between genetic variants and metabolite levels. However, only considering genetic variants and their effects on one trait ignores the possible interplay between different "omics" layers. Existing tools only consider single-nucleotide polymorphism (SNP)-SNP interactions, and no practical tool is available for large-scale investigations of the interactions between pairs of arbitrary quantitative variables. We developed an R package called pulver to compute p-values for the interaction term in a very large number of linear regression models. Comparisons based on simulated data showed that pulver is much faster than the existing tools. This is achieved by using the correlation coefficient to test the null-hypothesis, which avoids the costly computation of inversions. Additional tricks are a rearrangement of the order, when iterating through the different "omics" layers, and implementing this algorithm in the fast programming language C++. Furthermore, we applied our algorithm to data from the German KORA study to investigate a real-world problem involving the interplay among DNA methylation, genetic variants, and metabolite levels. The pulver package is a convenient and rapid tool for screening huge numbers of linear regression models for significant interaction terms in arbitrary pairs of quantitative variables. pulver is written in R and C++, and can be downloaded freely from CRAN at https://cran.r-project.org/web/packages/pulver/ .

LES and RANS modeling of pulverized coal combustion in swirl burner for air and oxy-combustion technologies

International Nuclear Information System (INIS)

Warzecha, Piotr; Boguslawski, Andrzej

2014-01-01

Combustion of pulverized coal in oxy-combustion technology is one of the effective ways to reduce the emission of greenhouse gases into the atmosphere. The process of transition from conventional combustion in air to the oxy-combustion technology, however, requires a thorough investigations of the phenomena occurring during the combustion process, that can be greatly supported by numerical modeling. The paper presents the results of numerical simulations of pulverized coal combustion process in swirl burner using RANS (Reynolds-averaged Navier–Stokes equations) and LES (large Eddy simulation) methods for turbulent flow. Numerical simulations have been performed for the oxyfuel test facility located at the Institute of Heat and Mass Transfer at RWTH Aachen University. Detailed analysis of the flow field inside the combustion chamber for cold flow and for the flow with combustion using different numerical methods for turbulent flows have been done. Comparison of the air and oxy-coal combustion process for pulverized coal shows significant differences in temperature, especially close to the burner exit. Additionally the influence of the combustion model on the results has been shown for oxy-combustion test case. - Highlights: • Oxy-coal combustion has been modeled for test facility operating at low oxygen ratio. • Coal combustion process has been modeled with simplified combustion models. • Comparison of oxy and air combustion process of pulverized coal has been done. • RANS (Reynolds-averaged Navier–Stokes equations) and LES (large Eddy simulation) results for pulverized coal combustion process have been compared

Kinetics of devolatilization and oxidation of a pulverized biomass in an entrained flow reactor under realistic combustion conditions

Energy Technology Data Exchange (ETDEWEB)

Jimenez, Santiago [LITEC-CSIC (Spanish Council for Scientific Research), Maria de Luna 10, 50018 Zaragoza (Spain); Remacha, Pilar; Ballester, Javier [LITEC-CSIC (Spanish Council for Scientific Research), Maria de Luna 10, 50018 Zaragoza (Spain); Fluid Mechanics Group, University of Zaragoza, Maria de Luna 3, 50018 Zaragoza (Spain); Ballesteros, Juan C.; Gimenez, Antonio [ENDESA GENERACION, S.A., Ribera del Loira 60, 28042 Madrid (Spain)

2008-03-15

In this paper the results of a complete set of devolatilization and combustion experiments performed with pulverized ({proportional_to}500 {mu}m) biomass in an entrained flow reactor under realistic combustion conditions are presented. The data obtained are used to derive the kinetic parameters that best fit the observed behaviors, according to a simple model of particle combustion (one-step devolatilization, apparent oxidation kinetics, thermally thin particles). The model is found to adequately reproduce the experimental trends regarding both volatile release and char oxidation rates for the range of particle sizes and combustion conditions explored. The experimental and numerical procedures, similar to those recently proposed for the combustion of pulverized coal [J. Ballester, S. Jimenez, Combust. Flame 142 (2005) 210-222], have been designed to derive the parameters required for the analysis of biomass combustion in practical pulverized fuel configurations and allow a reliable characterization of any finely pulverized biomass. Additionally, the results of a limited study on the release rate of nitrogen from the biomass particle along combustion are shown. (author)

Chemical and Physical Characteristics of Pulverized Granitic Rock Adjacent to the San Andreas, Garlock and San Jacinto Faults: Implications for Earthquake Physics

Science.gov (United States)

Rockwell, T. K.; Sisk, M.; Stillings, M.; Girty, G.; Dor, O.; Wechsler, N.; Ben-Zion, Y.

2008-12-01

We present new detailed analyses of pulverized granitic rocks from sections adjacent to the San Andreas, Garlock and San Jacinto faults in southern California. Along the San Andreas and Garlock faults, the Tejon Lookout Granite is pulverized in all exposures within about 100 m of both faults. Along the Clark strand of the San Jacinto fault in Horse Canyon, the pulverization of granitic rocks is highly asymmetric, with a much broader zone of pulverization along the southwest side of the Clark fault. In areas where the granite is injected as dyke rock into schist, only the granitic rock shows pulverization, demonstrating the control of rock type on the pulverization process. Chemical analyses indicate little or no weathering in the bulk of the rock, although XRD analysis shows the presence of smectite, illite, and minor kaolinite in the clay-sized fraction. Weathering products may dominate in the less than 1 micron fraction. The average grain size in all samples of pulverized granitic rock range between about 20 and 200 microns (silt to fine sand), with the size distribution in part a function of proximity to the primary slip zone. The San Andreas fault samples are generally finer than those collected from along the Garlock or San Jacinto faults. The particle size distribution for all samples is non-fractal, with a distinct slope break in the 60-100 micron range, which suggests that pulverization is not a consequence of direct shear. This average particle size is quite coarser than previous reports, which we attribute to possible measurement errors in the prior work. Our data and observations suggest that dynamic fracturing in the wall rock of these three major faults only accounts for 1% or less of the earthquake energy budget.

Utilization of pulverized fuel ash in Malta

International Nuclear Information System (INIS)

Camilleri, Josette; Sammut, Michael; Montesin, Franco E.

2006-01-01

In Malta all of the waste produced is mixed and deposited at various sites around the island. None of these sites were purpose built, and all of the waste is above groundwater level. The landfills are not engineered and do not contain any measures to collect leachate and gases emanating from the disposal sites. Another waste, which is disposed of in landfills, is pulverized fuel ash (PFA), which is a by-product of coal combustion by the power station. This has been disposed of in landfill, because its use has been precluded due to the radioactivity of the ashes. The aim of this study was to analyze the chemical composition of the pulverized fuel ash and to attempt to utilize it as a cement replacement in normal concrete mixes in the construction industry. The levels of radiation emitted from the ashes were measured by gamma spectrometry. The results of this study revealed that although at early ages cement replacement by PFA resulted in a reduction in compressive strength (P = 0), when compared to the reference concrete at later ages the strengths measured on concrete cores were comparable to the reference concrete (P > 0.05). The utilization of PFA up to 20% cement replacement in concrete did not raise the radioactivity of the concrete. In conclusion, utilization of PFA in the construction industry would be a better way of disposing of the ashes rather than controlling the leachate and any radioactivity emitted by the landfilled ashes

Possibilities of using pulverized non coking coals in ironmaking

Energy Technology Data Exchange (ETDEWEB)

Wijk, Olle; Mathiesen, Mihkel; Eketorp, Sven

1977-08-01

The use of pulverized coal in iron making suggests solutions to the mounting problems created by the increasing scarcity of coking coals, and other fossil fuels such as oil and natural gas. The unavailability of coke can be met with two principally different measures. Blast furnace coke rates can be decreased by substituting injected pulverized coal or other carbon containing fuels for part of the coke burden, and the coke itself may be substituted by formed coke. A more radical solution is to abandon the blast furnace process, and instead produce the raw iron in processes not requiring coke. Two such processes are discussed in the paper, the Inred process, developed by Boliden Kemi AB, Sweden, and the smelting reduction process by means of injection, currently being developed at the Royal Institute of Technology in Stockholm. Both processes have potential advantages over the coke oven/sintering plant/blast furnace-complex especially concerning energy requirements and structure, but also in economical terms. The injection process seems to present a further advantage in the possibility of gasifying coal in the process, thus yielding a synthesis gas for methanol production in addition to the raw iron.

A Machine for Pulverizing and Sifting Gari Mash | Odigboh | Nigerian ...

African Journals Online (AJOL)

A prototype machine for pulverizing and sifting gari mash, designed as a companion to the gari frying machine developed by the authors, was built and tested. Driven by an electric motor, the prototype accepts lump3 of dewatered gari mash cuts them up into small pieces by a cake breaker and delivers the pieces by a belt ...

A study on the compressive and tensile strength of foamed concrete containing pulverized bone as a partial replacement of cement

International Nuclear Information System (INIS)

Falade, F.

2013-01-01

In this study, structural properties of foamed aerated concrete with and without pulverized bone were investigated. These properties are workability, plastic and testing densities, compressive strength, and tensile strength at the design density of 1600kg/m/sub 3/. The tensile strength was evaluated by subjecting 150 x 150 x750mm unreinforced foamed concrete beams to flexural test and 150x300mm cylinder specimens were subjected to splitting test. 150mm cube specimens were used for the determination of both the compressive strength and the testing density of the foamed aerated concrete. The plastic density was investigated using a container of known volume, and its workability determined using the slump test. The pulverized bone content was varied from 0 to 20% at interval of 5%. The specimens without the pulverized bone served as the control. At the designed density of 1600 kg/m/sub 3/, the results for the control specimens at 28-day curing age are 15.43 and 13.89N/mm/sub 2/ for air-and water-cured specimens respectively. The modulus of rupture and splitting tensile strength are 2.53 and 1.63N/mm/sub 2/ respectively. The results for specimens with pulverized bone did not differ significantly from the specimens without pulverized bone. From the results of this investigation, it can be concluded that foamed aerated concrete used for this study has potential for structural applications. Also pulverized bone can be used to reduce (partially replace) the quantity of cement used in aerated concrete production; thus ridding our environment of potentially harmful wastes, as well as reduce the consumption of non-renewable resources. (author)

A Model for Nitrogen Chemistry in Oxy-Fuel Combustion of Pulverized Coal

DEFF Research Database (Denmark)

Hashemi, Hamid; Hansen, Stine; Toftegaard, Maja Bøg

2011-01-01

, heating and devolatilization of particles, and gas–solid reactions. The model is validated by comparison with entrained flow reactor results from the present work and from the literature on pulverized coal combustion in O2/CO2 and air, covering the effects of fuel, mixing conditions, temperature......In this work, a model for the nitrogen chemistry in the oxy-fuel combustion of pulverized coal has been developed. The model is a chemical reaction engineering type of model with a detailed reaction mechanism for the gas-phase chemistry, together with a simplified description of the mixing of flows......, stoichiometry, and inlet NO level. In general, the model provides a satisfactory description of NO formation in air and oxy-fuel combustion of coal, but under some conditions, it underestimates the impact on NO of replacing N2 with CO2. According to the model, differences in the NO yield between the oxy...

Properties of palm oil fuel ash cement sand brick containing pulverized cockle shell as partial sand replacement

Science.gov (United States)

Mat Aris, S.; Muthusamy, K.; Uzer, A.; Ahmad, S. Wan

2018-04-01

Environmental pollution caused by the disposal of solid wastes generated from both palm oil industry and cockle shell trade has motivated researches to explore the potential of these wastes. Integrating these wastes in production of construction material is one of the ways to reduce amount of waste thrown at dumping area. Thus, the present investigation investigates the performance of palm oil fuel ash (POFA) cement sand brick containing pulverized cockle shell as partial fine aggregate replacement. All mixes used contain 20% of POFA as partial cement replacement. Total of six mixes were prepared by adding a range of pulverized cockle shell that is 0%, 10%, 20%, 30%, 40% and 50% as partial sand replacement. The mixes were prepared in form of brick. All the water cured samples were tested for compressive strength and flexural strength until 28 days. Findings show that brick produced using 20% pulverized cockle shell exhibit the highest compressive strength and flexural strength also the lowest water absorption value.

Fluidized bed and pulverized coal combustion residues for secondary pavements

International Nuclear Information System (INIS)

Ghafoori, N.; Diawara, H.; Wang, L.

2009-01-01

The United States produced nearly 125 million tons of coal combustion products in 2006. These by-products include fly ash, flue gas desulphurization materials, bottom ash, boiler slag, and other power plant by-products. The expense associated with waste disposal, lack of disposal sites, and significant environmental damage linked with the disposal of coal combustion residues have encouraged innovative utilization strategies such as the fluidized bed combustion (FBC) unit. This paper presented the results of a laboratory investigation that examined the properties of composites developed with different proportions of pre-conditioned FBC spent bed, pulverized coal combustion fly ash, natural fine aggregate, and Portland cement. The purpose of the study was to examine the extent to which the by-product composites could replace currently used materials in secondary roads. The paper presented the research objectives and experimental programs, including matrix constituent and proportions; mixture proportions; and mixing, curing, sampling, and testing. The discussion of results centered around compressive strength and expansion by internal sulfate attack. It was concluded that with proper proportioning, by-products of pulverized and fluidized bed combustion promote binding of sand particles and provide adequate strength under various curing and moisture conditions 4 refs., 6 tabs.

Online X-ray Fluorescence (XRF) Analysis of Heavy Metals in Pulverized Coal on a Conveyor Belt.

Science.gov (United States)

Yan, Zhang; XinLei, Zhang; WenBao, Jia; Qing, Shan; YongSheng, Ling; DaQian, Hei; Da, Chen

2016-02-01

Heavy metals in haze episode will continue to threaten the quality of public health around the world. In order to decrease the emission of heavy metals produced from coal burning, an online X-ray fluorescence (XRF) analyzer system, consisting of an XRF analyzer with data acquisition software and a laser rangefinder, was developed to carry out the measurement of heavy metals in pulverized coal. The XRF analyzer was mounted on a sled, which can effectively smooth the surface of pulverized coal and reduce the impact of surface roughness during online measurement. The laser rangefinder was mounted over the sled for measuring the distance between a pulverized coal sample and the analyzer. Several heavy metals and other elements in pulverized coal were online measured by the XRF analyzer directly above a conveyor belt. The limits of detection for Hg, Pb, Cr, Ti, Fe, and Ca by the analyzer were 44 ± 2, 34 ± 2, 17 ± 3, 41 ± 4, 19 ± 3, and 65 ± 2 mg·kg(-1), respectively. The relative standard deviation (%RSD) for the elements mentioned was less than 7.74%. By comparison with the results by inductively-coupled plasma mass spectrometry (ICP-MS), relative deviation (%D) of the online XRF analyzer was less than 10% for Cr, Ti, and Ca, in the range of 0.8-24.26% for Fe, and greater than 20% for Hg and Pb. © The Author(s) 2016.

An investigation into fuel pulverization with specific reference to high burn-up LOCA

International Nuclear Information System (INIS)

Yagnik, Suresh; Turnbull, James; Noirot, Jean; Walker, Clive; Hallstadius, Lars; Waeckel, N.; Blanpain, P.

2014-01-01

To investigate the phenomenon of high burn-up fuel pellet material potentially disintegrating into powder under a rapid temperature transient, such as in a LOCA-type accident scenario, two independent scoping studies were commissioned. The first was to investigate the effect of hydrostatic restraint pressure on Fission Gas Release (FGR) from small samples of highly irradiated fuel (71 MWd/kgU) during a series of rapid temperature ramps. Experimentally, when the FGR increased rapidly during the temperature transients, the fuel was assumed to be 'pulverized', i.e., fragmented into powder. In the second series of experiments, laser heating of small samples was used to investigate the temperature at which fuel pulverization was initiated. Subsequent to fuel disintegration, there was always a spectrum of particle sizes present. The significance of this observation was recognized in the context of extended burn-up operation in commercial reactors. Based on the observation from these investigations, a fuel fragmentation threshold has been discussed and developed. We conclude that fuel disintegration could be of potential importance in limiting the performance and productive lifetime of nuclear fuel. However, since only fuel closely adjacent to ballooned or ruptured cladding would be released in a LOCA-type transient, expulsion of pulverized fuel from the ruptured fuel rod is not considered a safety issue; cooling of the defected assembly remains possible and there is no issue with respect to local criticality. (author)

Perancangan Sistem Pemeliharaan Menggunakan Metode Reliability Centered Maintenance (RCM Pada Pulverizer (Studi Kasus: PLTU Paiton Unit 3

Directory of Open Access Journals (Sweden)

RATNA BHAKTI PUSPITA SARI

2017-03-01

Full Text Available PLTU Paiton Unit 3 merupakan perusahaan yang bergerak di bidang produksi listrik menggunakan bahan baku batubara yang terletak di Paiton, Probolinggo. Untuk mencapai target, proses produksi dilakukan 24 jam selama 1 tahun tanpa henti. Program pemeliharaan mesin sangat penting untuk kelancaran proses produksi. Dalam rangka mencapai target tersebut dituntut adanya kelancaran batubara dari silo hingga surface burner menggunakan pulverizer. Data dari Departemen Engineering menunjukkan bahwa beberapa subsistem pulverizer sering mengalami kerusakan yang dapat menimbulkan kegagalan pada sistem tersebut. Penelitian tugas akhir ini menggunakan metode Reliability Centered Maintenance (RCM untuk menurunkan tingkat breakdown mesin dan downtime produksi. Data historis kerusakan pulverizer dianalisa. Kemudian kegagalan dari suatu komponen yang dapat menyebabkan kegagalan fungsi dari sistem diidentifikasi menggunakan metode Failure Mode and Effect Analysis (FMEA. Selanjutnya menggunakan RCM Decision Worksheet untuk mengetahui bagian dari sistem yang gagal dan perlu dilakukan tindakan perbaikan dan pencegahan berdasarkan kegagalan yang ada agar kejadian yang sama tidak terulang dan menentukan kegiatan perancang perawatan yang tepat pada setiap komponen Berdasarkan analisis data secara Reliability Centered Maintenance (RCM terdapat 12 failure mode yang terjadi pada pulverizer. 3 failure mode dapat dicegah dengan scheduled restoration task, 8 failure mode dapat dicegah dengan scheduled discard task, dan 1 failure mode dapat dicegah dengan redesign. Analisis kuantitatif menggunakan distribusi kegagalan dengan perangkat lunak Weibull++6 didapatkan MTBF grinding roller 2880,66 jam, MTBF hydraulic pump 5075,06 jam, MTBF gearbox 5381,65 jam dan MTBF coal feeder 525,17 jam.

Experimental Research on the Impactive Dynamic Effect of Gas-Pulverized Coal of Coal and Gas Outburst

Directory of Open Access Journals (Sweden)

Haitao Sun

2018-03-01

Full Text Available Coal and gas outburst is one of the major serious natural disasters during underground coal, and the shock air flow produced by outburst has a huge threat on the mine safety. In order to study the two-phase flow of a mixture of pulverized coal and gas of a mixture of pulverized coal and gas migration properties and its shock effect during the process of coal and gas outburst, the coal samples of the outburst coal seam in Yuyang Coal Mine, Chongqing, China were selected as the experimental subjects. By using the self-developed coal and gas outburst simulation test device, we simulated the law of two-phase flow of a mixture of pulverized coal and gas in the roadway network where outburst happened. The results showed that the air in the roadway around the outburst port is disturbed by the shock wave, where the pressure and temperature are abruptly changed. For the initial gas pressure of 0.35 MPa, the air pressure in different locations of the roadway fluctuated and eventually remain stable, and the overpressure of the outburst shock wave was about 20~35 kPa. The overpressure in the main roadway and the distance from the outburst port showed a decreasing trend. The highest value of temperature in the roadway increased by 0.25 °C and the highest value of gas concentration reached 38.12% during the experiment. With the action of shock air flow, the pulverized coal transportation in the roadway could be roughly divided into three stages, which are the accelerated movement stage, decelerated movement stage and the particle settling stage respectively. Total of 180.7 kg pulverized coal of outburst in this experiment were erupted, and most of them were accumulated in the main roadway. Through the analysis of the law of outburst shock wave propagation, a shock wave propagation model considering gas desorption efficiency was established. The relationships of shock wave overpressure and outburst intensity, gas desorption rate, initial gas pressure, cross

Deposit formation in a full-scale pulverized wood-fired power plant with and without coal fly ash addition

DEFF Research Database (Denmark)

Wu, Hao; Shafique Bashir, Muhammad; Jensen, Peter Arendt

2013-01-01

Ash transformation and deposition in a pulverized wood-fired power plant boiler of 800 MWth were studied with and without the addition of coal fly ash. The transient ash deposition behavior was investigated by using an advanced deposit probe system at two different boiler locations with flue gas...... at the low-temperature location showed a slow initial build-up and a stable mass of deposits after approximately 1-5 h. The deposits collected during pulverized wood combustion contained a considerable amount of K2SO4, KCl, and KOH/K2CO3. With the addition of coal fly ash (~4 times of the mass flow of wood...... ash) to the boiler, these alkali species were effectively removed both in the fly ash and in the deposits, and a more frequent shedding of the deposits was observed. The results imply that coal fly ash can be an effective additive to reduce ash deposition and corrosion problems in a pulverized wood...

Liquid carbon dioxide/pulverized limestone globulsion delivery system for deep ocean storage

Energy Technology Data Exchange (ETDEWEB)

Swett, P.; Golomb, D.; Barry, E.; Ryan, D.; Lawton, C. [Massachusetts Univ., Lowell, MA (United States)

2005-07-01

Ocean storage of carbon dioxide (CO{sub 2}) raises serious environmental, technical and economic problems because a massive point injection of pure liquid CO{sub 2} at depth would create a plume of carbonic acid with a pH lower than 7. Acidified seawater is considered to be harmful to aquatic organisms. Laboratory studies have shown that injecting a globulsion consisting of CO{sub 2}, water (H{sub 2}O) and calcium carbonate (CaCO{sub 3}) instead of pure liquid CO{sub 2} results in an alkaline reaction rather than an acidic reaction. Because calcium carbonate and bicarbonate are natural ingredients of seawater, there is no expected harm due to the additive limestone. This paper presented a practical delivery system for the underwater creation of globulsion. When liquid or supercritical CO{sub 2} is mixed with a slurry of finely pulverized limestone (CaCO{sub 3}) in pure or seawater, a macro-emulsion is formed consisting of CO{sub 2} droplets coated with CaCO{sub 3} particles dispersed in water. In this study, liquid CO{sub 2} was piped to approximately 500 m depth, which is below the flash point of liquid CO{sub 2} into vapor. A slurry of pulverized limestone in seawater was also separately piped to this depth. A static mixer was mounted at the end of the pipes. Liquid CO{sub 2}, along with a slurry of pulverized limestone and ambient seawater were pumped into the mixer by a turbine. The globulsion exited from the other end of the mixer and sank like a dense plume to greater depths while entraining ambient seawater. The CaCO{sub 3}-coated globules precipitated from the neutrally buoyant plume toward the ocean bottom following equilibration. As such, the ocean was not be acidified with this method of CO{sub 2} discharging. It was concluded that even inland seas, such as the Mediterranean and Black Seas, could be considered for sequestration of a CO{sub 2}/H{sub 2}O/CaCO{sub 3} globulsion. Although adding pulverized limestone to liquid CO{sub 2} and the mixing

The pulverization and handling of soft plastics for energy recovery; Soenderdelning och hantering av mjuka plaster foer energiutvinning

Energy Technology Data Exchange (ETDEWEB)

Wiklund, Sven-Erik

2000-10-01

The purpose of the project has primarily been to investigate suitable equipment (mills, crushers, shredders) for the pulverization of different types of soft plastics from the agricultural sector (large sacks and silage plastic) and the peat extraction industry (plastic covers) with the aim of being able to use the plastic material as fuel in conventional solid waste-fired plants. Many of the mills that are used for pulverizing different types of biofuel have proved not to be particularly suitable for soft plastics. The project has comprised the following: * Contact with a number of plant owners with different types of plants (grate, CFB and BFB boilers) for a review of existing fuel handling and fuel feed equipment as well as the demands they make on the fuel that is to be fired. * Contact with Trio Plast concerning previous tests carried out in connection with the collection, baling, handling, pulverization and combustion of plastics from the agricultural sector. * Contact with mill suppliers for participation in the tests and for feedback on experience gained in connection with the pulverization of soft plastics. * Choice of a suitable plant for practical trials based on contact with the above plant owners as a reference group. * Practical trials in 5 mills with the pulverization of soft plastics from agriculture (silage plastic and large sacks) as well as plastic from peat extraction (plastic covers) and * Evaluation of technical, economic, energy-related and environmental preconditions. Following contact with several owners of solid waste-fired combustion plants, and after hearing their opinions, it became clear that many of them were doubtful about the combustion of plastic. They are primarily afraid of tripping superheaters, etc. Consequently, two plants without superheaters, one in Oestersund and the other in Malmoe, were chosen for the tests. The mills that were tested were: * A SIM mill from WahIkvist, Oedeshoeg Plant - a mobile slow-action pulverizer for

Numerical simulation of pulverized coal combustion to reduce pollutants

International Nuclear Information System (INIS)

Mohammad Bagher Ayani; Behnam Rahmanian

2010-01-01

Full text: In this research, the numerical simulation of pollutant reduction and in a pulverized coal combustion at 2D combustion chamber have been studied. Finite volume method using structured grid arrangement was utilized for modeling the pulverized coal combustion. The pressure base algorithm and implicit solver has been employed to simulate non-premix combustion model. The air was diluted by some participative gaseous such as whose percentages varied from 0 % to 20 %. Participative gases and air were preheated by a high-temperature gas generator, and the preheated oxidizer temperature could achieve. The combustion simulation with the generalized finite rate chemistry model, referred to as the Magnussen model and the reacting flow with the mixture fraction PDF/ equilibrium chemistry model, referred to as the PDF model are studied. Quick scheme was adopted for the discretization of all convective terms of the advective transport equations. So, as a result of addition participative gases into oxidizer the rate of formation of pollutants as well as NO x suppressed. The addition only a few percent of halogen components can make some systems nonflammable. The effects of addition halogen components and non-reaction gaseous such as Helium and Argon are fuel dilution and its acts as catalysts in reducing the H atom concentration necessary for the chain branching reaction sequence. Moreover, they act like surface and they make the increment of surface ratio versus volume. Because of this, the number of radical conflicts and hence destruction them will be increase. Furthermore, the rate of formation of pollutants will be decreased if the halogen components and non-reaction gaseous injection will be increased. However, as a result of this research, in the case of injection in pulverized coal combustion the flame temperature is lower than Steam, Argon and Helium. So, the emission levels of carbon dioxide is significantly lower than other participative gases, but in this

Pyrolysis of superfine pulverized coal. Part 4. Evolution of functionalities in chars

International Nuclear Information System (INIS)

Liu, Jiaxun; Ma, Yang; Luo, Lei; Ma, Junfang; Zhang, Hai; Jiang, Xiumin

2017-01-01

Highlights: • A combination of XPS and NMR is adopted for analyzing char chemical structures during superfine pulverized coal pyrolysis. • The chemisorbed NO can be transformed into pyridine N with the favor of adjacent oxygenated groups in chars. • Particle size has significant influence on oxygen-containing configurations in chars. - Abstract: The properties of the coal-derived char play crucial roles in coal conversion reactions and the formation of air pollutants. The nascent char is highly reactive due to the existence of numerous free radicals, active sites, and organic functional groups on its surface. Here, we showed that a combination of nuclear magnetic resonance spectroscopy (NMR) and X-ray photoelectron spectroscopy (XPS) techniques is an effective and precise way to characterize the occurrence, distribution, and evolution of organic functionalities in coal chars. Using these methods, we explored detailed information about chemical features of superfine pulverized coal chars in different atmospheres, and we also discussed the influence of particle size on the evolutionary behavior of functionalities. Results indicate that, in both N_2 and CO_2 atmospheres, the content of C−O species increases with the reduction in char particle sizes. This increment facilitates the heterogeneous reduction of NOx on char surfaces. The chemisorbed NO is susceptible to being incorporated into chars, and being transformed into pyridine-type nitrogen with the favor of adjacent oxygen-containing groups. Moreover, the significant increment in oxygen-containing groups with the reduction of particle size is further confirmed through "1"3C NMR analysis. It was shown that there is an excellent correlation between estimates derived from XPS and NMR for oxygen configuration. The findings from this work provide some new insights into NOx reduction mechanisms and shed light on the practical application of superfine pulverized coal in the future.

Combustion of pulverized coal in counter-current flow

Energy Technology Data Exchange (ETDEWEB)

Timnat, Y M; Goldman, Y [Technion-Israel Inst. of Tech., Haifa (Israel). Faculty of Aerospace Engineering

1991-01-01

In this report we describe the results obtained with two prototypes of pulverized coal combustors operating in counter-current flow, one at atmospheric pressure, the other at higher pressure and compare them to the predictions of a theoretical-numerical model, we have developed. The first prototype treats a vertical configuration, eight times larger than the one treated before (Hazanov et al. 1985), while in the second a horizontal arrangement with a smaller volume is studied. Attention was focused on particle trajectories, burnout, angle of injection, ash separation by rotational motion, effects of initial particle size and temperature, impingement velocity and the effect of gravity. Main development activity was directed to achieving stable and reliable coal burning in the combustors.

Physical and chemical characterization of 50 pulverized coal ashes with respect to partial cement replacement in concrete

Energy Technology Data Exchange (ETDEWEB)

Van der Sloot, H A; Weijers, E G

1986-04-01

Physical and chemical characterization of 50 pulverized coal ashes from Dutch, Belgian and German installations has been carried out to identify the parameters that have to be kept under control, when pulverized coal ashes are to be used as partial cement replacement in concrete. For a good workability of fly ash/cement mortars the particle size and the carbon content are important. By performing a mortar flow test (Heagermann) upon delivery exterme ashes can be easily eliminated. The compressive strength is largely determined by the fineness of the ash (weight fraction below 20 micron). A direct effect of carbon content on strength development is not observed, but a reduction in mortar slow due to carbon leads to loss in strength, while the workability has to be adjusted. Size distribution measurement by optical methods is recommended as the relevant part of the ash size distribution cannot be properly assessed by sieve methods. The net contribution of fly ash to the compressive strength of a fly ash/cement (20/80) mortar exhibits a minimum at 14 days curing, which is common to all 50 ashes studied. Improvements in ash quality as obtained from pulverized-coal fired installations can be achieved by improvements in coal milling and optimizing ash collection. 6 figs., 4 tabs., 19 refs.

Review of coal-water fuel pulverization technology and atomization quality registration methods

Directory of Open Access Journals (Sweden)

Zenkov Andrey

2017-01-01

Full Text Available Possibilities of coal-water fuel application in industrial power engineering are considered and described. Two main problems and disadvantages of this fuel type are suggested. The paper presents information about liquid fuel atomization technologies and provides data on nozzle type for coal-water fuel pulverization. This article also mentions some of the existing technologies for coal-water slurry spraying quality determination.

On gas and particle radiation in pulverized fuel combustion furnaces

DEFF Research Database (Denmark)

Yin, Chungen

2015-01-01

Radiation is the principal mode of heat transfer in a combustor. This paper presents a refined weighted sum of gray gases model for computational fluid dynamics modelling of conventional air-fuel combustion, which has greater accuracy and completeness than the existing gaseous radiative property...... models. This paper also presents new conversion-dependent models for particle emissivity and scattering factor, instead of various constant values in literature. The impacts of the refined or new models are demonstrated via computational fluid dynamics simulation of a pulverized coal-fired utility boiler...

Numerical simulation of altitude impact on pulverized coal combustion

Energy Technology Data Exchange (ETDEWEB)

Pei, Xiaohui; He, Boshu; Ling, Ling; Wang, Lei [Beijing Jiaotong Univ., Beijing (China). Inst. of Mechanical, Electronic and Control Engineering

2013-07-01

A drop-tube Furnace simulation model has been developed to investigate the pulverized coal combustion characteristics under different altitudes using the commercially available software Fluent. The altitude conditions of 0, 500, 1,000, 1,500 m have been discussed. The results included the fields of temperature, pressure, velocity, the coal burnout, CO burnout and NO emission in the tube furnace. The variation of these parameters with altitude has been analyzed. The coal combustion characteristics were affected by the altitude. The time and space for coal burnout should be increased with the rise of altitude. The valuable results could be referenced in the design of coal- fired furnaces for the high altitude areas.

Effects of moisture release and radiation properties in pulverized fuel combustion

DEFF Research Database (Denmark)

Yin, Chungen

2016-01-01

and impacts via a computational fluid dynamics (CFD) study of a 609 MWe pulverized coal-fired utility boiler. Overall speaking, it is suggested to add the free moisture in the fuel to the primary air stream while lump the bound moisture with volatiles in PF combustion modelling, although different methods.......g., oxy-fuel or air–fuel), account for the variations in CO2 and H2O concentrations in a flame, and include the impacts of other participating gases (e.g., CO and hydrocarbons) needs to be derived for combustion CFD community....

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

Directory of Open Access Journals (Sweden)

Belošević Srđan V.

2016-01-01

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

Pulverized straw combustion in a low-NOx multifuel burner

DEFF Research Database (Denmark)

Mandø, Matthias; Rosendahl, Lasse; Yin, Chungen

2010-01-01

A CFD simulation of pulverized coal and straw combustion using a commercial multifuel burner have been undertaken to examine the difference in combustion characteristics. Focus has also been directed to development of the modeling technique to deal with larger non-spherical straw particles...... and to determine the relative importance of different modeling choices for straw combustion. Investigated modeling choices encompass the particle size and shape distribution, the modification of particle motion and heating due to the departure from the spherical ideal, the devolatilization rate of straw......, the influence of inlet boundary conditions and the effect of particles on the carrier phase turbulence. It is concluded that straw combustion is associated with a significantly longer flame and smaller recirculation zones compared to coal combustion for the present air flow specifications. The particle size...

Conceptual designs of pressurized fluidized bed and pulverized coal fired power plants

International Nuclear Information System (INIS)

Doss, H.S.; Bezella, W.A.; Hamm, J.R.; Pietruszkiewicz, J.

1984-01-01

This paper presents the major technical and economic characteristics of steam and air-cooled pressurized fluidized bed (PFB) power plant concepts, along with the characteristics of a pulverized coal fired power plant equipped with an adipic acid enhanced wet-limestone flue gas desulfurization system. Conceptual designs for the three plants were prepared to satisfy a set of common groundrules developed for the study. Grassroots plants, located on a generic plant site were assumed. The designs incorporate technologies projected to be commercial in the 1990 time frame. Power outputs, heat rates, and costs are presented

Relationship between Particle Size Distribution of Low-Rank Pulverized Coal and Power Plant Performance

Directory of Open Access Journals (Sweden)

Rajive Ganguli

2012-01-01

Full Text Available The impact of particle size distribution (PSD of pulverized, low rank high volatile content Alaska coal on combustion related power plant performance was studied in a series of field scale tests. Performance was gauged through efficiency (ratio of megawatt generated to energy consumed as coal, emissions (SO2, NOx, CO, and carbon content of ash (fly ash and bottom ash. The study revealed that the tested coal could be burned at a grind as coarse as 50% passing 76 microns, with no deleterious impact on power generation and emissions. The PSD’s tested in this study were in the range of 41 to 81 percent passing 76 microns. There was negligible correlation between PSD and the followings factors: efficiency, SO2, NOx, and CO. Additionally, two tests where stack mercury (Hg data was collected, did not demonstrate any real difference in Hg emissions with PSD. The results from the field tests positively impacts pulverized coal power plants that burn low rank high volatile content coals (such as Powder River Basin coal. These plants can potentially reduce in-plant load by grinding the coal less (without impacting plant performance on emissions and efficiency and thereby, increasing their marketability.

Reconstruction of the aero-mixture channels of the pulverized coal plant of the 100MW power plant unit

Directory of Open Access Journals (Sweden)

Ivanovic Vladan B.

2011-01-01

Full Text Available After the last revitalization of thermal power block of 100 MW in TPP “Kostolac A”, made in the year 2004, during the operation of the plant, pulverized coal deposition often occurred in horizontal sections of the aero-mixture channels. Deposition phenomenon manifested itself in places ahead of spherical compensators in the direction of flow of pulverized coal to the burners, due to unfavorable configuration of these channels. Coal dust deposited in the channels dried and spontaneously combusted, causing numerous damage to channels and its isolation as well as the frequent stoppage of the operation for necessary interventions. The paper presents the original solution of reconstruction of aero-mixture channels which prevented deposition of coal dust and its eventual ignition. In this way the reliability of the mill plant is maximized and higher availability of boiler and block as a whole is achieved.

Quantitative characterization of pulverized coal and biomass–coal blends in pneumatic conveying pipelines using electrostatic sensor arrays and data fusion techniques

International Nuclear Information System (INIS)

Qian, Xiangchen; Wang, Chao; Yan, Yong; Shao, Jiaqing; Wang, Lijuan; Zhou, Hao

2012-01-01

Quantitative data about the dynamic behaviour of pulverized coal and biomass–coal blends in fuel injection pipelines allow power plant operators to detect variations in fuel supply and oscillations in the flow at an early stage, enable them to balance fuel distribution between fuel feeding pipes and ultimately to achieve higher combustion efficiency and lower greenhouse gas emissions. Electrostatic sensor arrays and data fusion algorithms are combined to provide a non-intrusive solution to the measurement of fuel particle velocity, relative solid concentration and flow stability under pneumatic conveying conditions. Electrostatic sensor arrays with circular and arc-shaped electrodes are integrated in the same sensing head to measure ‘averaged’ and ‘localized’ characteristics of pulverized fuel flow. Data fusion techniques are applied to optimize and integrate the results from the sensor arrays. Experimental tests were conducted on the horizontal section of a 150 mm bore pneumatic conveyor circulating pulverized coal and sawdust under various flow conditions. Test results suggest that pure coal particles travel faster and carry more electrostatic charge than biomass–coal blends. As more biomass particles are added to the flow, the overall velocity of the flow reduces, the electrostatic charge level on particles decreases and the flow becomes less stable compared to the pure coal flow. (paper)

Quantitative characterization of pulverized coal and biomass-coal blends in pneumatic conveying pipelines using electrostatic sensor arrays and data fusion techniques

Science.gov (United States)

Qian, Xiangchen; Yan, Yong; Shao, Jiaqing; Wang, Lijuan; Zhou, Hao; Wang, Chao

2012-08-01

Quantitative data about the dynamic behaviour of pulverized coal and biomass-coal blends in fuel injection pipelines allow power plant operators to detect variations in fuel supply and oscillations in the flow at an early stage, enable them to balance fuel distribution between fuel feeding pipes and ultimately to achieve higher combustion efficiency and lower greenhouse gas emissions. Electrostatic sensor arrays and data fusion algorithms are combined to provide a non-intrusive solution to the measurement of fuel particle velocity, relative solid concentration and flow stability under pneumatic conveying conditions. Electrostatic sensor arrays with circular and arc-shaped electrodes are integrated in the same sensing head to measure ‘averaged’ and ‘localized’ characteristics of pulverized fuel flow. Data fusion techniques are applied to optimize and integrate the results from the sensor arrays. Experimental tests were conducted on the horizontal section of a 150 mm bore pneumatic conveyor circulating pulverized coal and sawdust under various flow conditions. Test results suggest that pure coal particles travel faster and carry more electrostatic charge than biomass-coal blends. As more biomass particles are added to the flow, the overall velocity of the flow reduces, the electrostatic charge level on particles decreases and the flow becomes less stable compared to the pure coal flow.

Low NO{sub x} burner modifications to front-fired pulverized coal boilers

Energy Technology Data Exchange (ETDEWEB)

Broderick, R G; Wagner, M

1998-07-01

Madison Gas and Electric Blount Street Station Units 8 and 9 are Babcock and Wilcox pulverized coal fired and natural gas fired boilers. These boilers were build in the late 1950's and early 1960's with each boiler rated at 425,000 lb./hr of steam producing 50 MW of electricity. The boilers are rated at 9,500 F at 1,350 psig. Each unit is equipped with one Ljungstroem air heater and two B and W EL pulverizers. These units burn subbituminous coal with higher heating value of 10,950 Btu/LB on an as-received basis. The nitrogen content is approximately 1.23% with 15% moisture. In order to comply with the new Clean Air Act Madison Gas and Electric needs to reduce NO{sub x} on these units to less than .5 LB/mmBtu. Baseline NO{sub x} emissions on these units range between .8--.9 lb./mmBtu. LOIs average approximately 8%. Madison Gas and Electric contracted with RJM Corporation to modify the existing burners to achieve this objective. These modifications consisted of adding patented circumferentially and radially staged flame stabilizers, modifying the coal pipe, and replacing the coal impeller with a circumferentially staged coal spreader. RJM Corporation utilized computational fluid dynamics modeling in order to design the equipment to modify these burners. The equipment was installed during the March 1997 outage and start-up and optimization was conducted in April 1997. Final performance results and economic data will be included in the final paper.

Simulation of blast furnace operation during the substitution of coke and pulverized coal with granulated waste plastic

Directory of Open Access Journals (Sweden)

Kovačević Tihomir M.

2014-01-01

Full Text Available The possibility of using the waste plastic as reducing agent in blast furnace for obtaining pig iron is in focus for the past couple year. The simulation of blast furnace process in BFC software has been performed in order to analyze the coke and coals saving, CO2 emission and determining the economic benefits. Three different batches were made for comparative analysis, depending on the batch composition and input of batch components into the blast furnace: case 1 (C1, case 2 (C2 and case 3 (C3. The base case, C1 contains sinter (bulk material which is needed for obtaining 1 tone of pig iron, quartz which provides slag alkalinity and coke as reducing and energy agent. C2 has the same components as C1, but contains pulverized coal instead one part of coke and C3 contains granulated waste plastic instead coke in an approximately the same amount as pulverized coal. The substitution of coke with pulverized coal and waste plastic is 18.6 % and 25.2 %, respectively. The economic, productivity and ecologic aspects have been analyzed. The consumption of each tone of waste plastic in blast furnace saves 360 $, which is 18 times more than its price, bearing in mind that the market price of coke is 380 $/t % and waste plastic 20 $/t. Regarding the specific productivity, it decreases from 2.13 for C1 to 1.87 for C3. From an environmental aspect there are two main benefits: reduction of CO2 emission and impossibility of dioxin formation. The CO2 emission was 20.18, 19.46 and 17.21 for C1, C2 and C3, respectively.

SYSTEM OF PRECISE DOSING OF COAGULANT IN THE PULVERIZING AERATOR POWERED BY WIND USING FUZZY LOGIC

Directory of Open Access Journals (Sweden)

Andrzej Osuch

2017-06-01

Full Text Available One of the methods used to support land restoration lakes is the method of pulverizing aeration. Use of aerators powered exclusively by wind improves the condition of reservoirs, while not compromising the environment. The pulverizing aeration process drive is windy on the water aeration zone near bottom, while removing harmful gases anaerobic metabolism. Aerators of this type due to the unique method of operation also enable dosing of inactivation coagulants with oxygenated water to the depths of the lake. Mileage coagulant dosing can be made dependent on the speed of the wind, which has an impact on the performance of his work, because with the increase of wind speed dispensing valve coagulants should be stronger open. One of the methods for assessing the state of lakes is to measure water transparency. The softer visibility, the most likely state of the water is better. Dosage of coagulant so you can make the transparency of the water. Similarly, with increasing transparency water dispensing valve should be more covered up. Control of the drain valve dispenser coagulant can be simultaneously dependent on two factors. The study was designed method of control drain valve dispenser coagulant using fuzzy inference.

Optimization of a lignite-fired open pulverizing system boiler process based on variations in the drying agent composition

International Nuclear Information System (INIS)

Ma, Youfu; Zhang, Hua; Yuan, Yichao; Wang, Zhiyun

2015-01-01

This paper evaluates three lignite-fired OPSB (open pulverizing system boiler) processes, named OPSB-A, OPSB-B and OPSB-C, corresponding to three options of drying agents used for the pulverizing systems. OPSB-B is similar to our previous work [18] on drying agent composition. Performances of the three OPSBs were calculated and compared with a 600 MW lignite-fired boiler as the reference. The results showed that the coal savings of OPSB-A and OPSB-C were 5.41% and 4.06% in comparison with the reference boiler, whereas for OPSB-B, the savings was 2.57%. Accordingly, emissions of each OPSB could be reduced in proportion to the coal savings. Among the three OPSBs, OPSB-C showed the best performance of water recovery from mill-exhausts because it had the highest mill-exhaust water dew point of 73.2 °C, whereas the exhaust dew points of OPSB-A and OPSB-B were 63.9 °C and 70.9 °C, respectively. Both OPSB-C and OPSB-B are beneficial for achieving a high mill-exhaust humidity ratio, which facilitates water recovery from the mill-exhaust, and a low oxygen content in mill-exhaust, which improves the operating safety of the pulverizing systems, whereas OPSB-A is relatively inferior in these respects. The OPSB-C process is recommended for engineering applications because of its favorable overall performances. - Highlights: • Three lignite-fired OPSB processes are analyzed based on a conventional 600 MW boiler. • OPSB-A, OPSB-B and OPSB-C show coal savings of 5.41%, 2.57 and 4.06%, respectively. • All OPSBs have a great advantage of water recovery from the flue gas, especially OPSB-C. • OPSB-C process is recommended in view of its favorable overall performances

Particle-size distribution (PSD) of pulverized hair: A quantitative approach of milling efficiency and its correlation with drug extraction efficiency.

Science.gov (United States)

Chagas, Aline Garcia da Rosa; Spinelli, Eliani; Fiaux, Sorele Batista; Barreto, Adriana da Silva; Rodrigues, Silvana Vianna

2017-08-01

Different types of hair were submitted to different milling procedures and their resulting powders were analyzed by scanning electron microscopy (SEM) and laser diffraction (LD). SEM results were qualitative whereas LD results were quantitative and accurately characterized the hair powders through their particle size distribution (PSD). Different types of hair were submitted to an optimized milling conditions and their PSD was quite similar. A good correlation was obtained between PSD results and ketamine concentration in a hair sample analyzed by LC-MS/MS. Hair samples were frozen in liquid nitrogen for 5min and pulverized at 25Hz for 10min, resulting in 61% of particles sample extracted after pulverization comparing with the same sample cut in 1mm fragments. When milling time was extended to 25min, >90% of particles were sample retesting and quality control procedures. Copyright © 2017 Elsevier B.V. All rights reserved.

Pulverizing processes affect the chemical quality and thermal property of black, white, and green pepper (Piper nigrum L.).

Science.gov (United States)

Liu, Hong; Zheng, Jie; Liu, Pengzhan; Zeng, Fankui

2018-06-01

In this study, the effects of different pulverizing methods on the chemical attributes and thermal properties of black, white and green pepper were evaluated. Cryogenic grinding minimally damaged the lipid, moisture, crude protein, starch, non-volatile ether extract, piperine, essential oil and the typical pepper essential oil compounds of the spices. The pulverizing methods and storage significantly affected the compositions of the fatty acid in the peppers, except for palmitic acid and lignoceric acid. The amino acid contents and the thermo-gravimetric analysis curve were hardly influenced by the grinding techniques. The use of cryogenic grinding to prepare pepper ensured the highest quality of pepper products. Regardless of grinding technique, the values of moisture, piperine, unsaturated fatty acids, essential oil, monoterpenes, and the absolute concentrations of typical pepper essential oil constituents (except caryophyllene oxide) decreased, whereas the amino acid, lipid, protein, starch, and non-volatile ether extract content as well as the thermal properties were insignificantly changed after storage at 4 °C for 6 months.

Low-Pressure and Low-Temperature Hydriding-Pulverization-Dehydriding Method for Producing Shape Memory Alloy Powders

Science.gov (United States)

Murguia, Silvia Briseño; Clauser, Arielle; Dunn, Heather; Fisher, Wendy; Snir, Yoav; Brennan, Raymond E.; Young, Marcus L.

2018-04-01

Shape memory alloys (SMAs) are of high interest as active, adaptive "smart" materials for applications such as sensors and actuators due to their unique properties, including the shape memory effect and pseudoelasticity. Binary NiTi SMAs have shown the most desirable properties, and consequently have generated the most commercial success. A major challenge for SMAs, in particular, is their well-known compositional sensitivity. Therefore, it is critical to control the powder composition and morphology. In this study, a low-pressure, low-temperature hydriding-pulverization-dehydriding method for preparing well-controlled compositions, size, and size distributions of SMA powders from wires is presented. Starting with three different diameters of as-drawn martensitic NiTi SMA wires, pre-alloyed NiTi powders of various well-controlled sizes are produced by hydrogen charging the wires in a heated H3PO4 solution. After hydrogen charging for different charging times, the wires are pulverized and subsequently dehydrided. The wires and the resulting powders are characterized using scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction. The relationship between the wire diameter and powder size is investigated as a function of hydrogen charging time. The rate of diameter reduction after hydrogen charging of wire is also examined. Finally, the recovery behavior due to the shape memory effect is investigated after dehydriding.

Impact of Coal Fly Ash Addition on Combustion Aerosols (PM2.5) from Full-Scale Suspension-Firing of Pulverized Wood

DEFF Research Database (Denmark)

Damø, Anne Juul; Wu, Hao; Frandsen, Flemming

2014-01-01

The formation of combustion aerosols was studied in an 800 MWth suspension-fired power plant boiler, during combustion of pulverized wood pellets with and without addition of coal fly ash as alkali capture additive. The aerosol particles were sampled and characterized by a low-pressure cascade im...

Volatile release and particle formation characteristics of injected pulverized coal in blast furnaces

International Nuclear Information System (INIS)

Chen, Wei-Hsin; Du, Shan-Wen; Yang, Tsung-Han

2007-01-01

Volatiles release and particle formation for two kinds of pulverized coals (a high volatile bituminous coal and a low volatile bituminous coal) in a drop tube furnace are investigated to account for the reactions of pulverized coal injected in blast furnaces. Two different sizes of feed particles are considered; one is 100-200 mesh and the other is 200-325 mesh. By evaluating the R-factor, the devolatilization extent of the larger feed particles is found to be relatively poor. However, the swelling behavior of individual or two agglomerated particles is pronounced, which is conducive to gasification of the chars in blast furnaces. In contrast, for the smaller feed particles, volatiles liberated from the coal particles can be improved in a significant way as a result of the amplified R-factor. This enhancement can facilitate the performance of gas phase combustion. Nevertheless, the residual char particles are characterized by agglomeration, implying that the reaction time of the char particles will be lengthened, thereby increasing the possibility of furnace instability. Double peak distributions in char particle size are observed in some cases. This possibly results from the interaction of the plastic state and the blowing effect at the particle surface. Considering the generation of tiny aerosols composed of soot particles and tar droplets, the results indicate that their production is highly sensitive to the volatile matter and elemental oxygen contained in the coal. Comparing the reactivity of the soot to that of the unburned char, the former is always lower than the latter. Consequently, the lower is the soot formation, the better is the blast furnace stability

Anatomy of an upgraded pulverized coal facility: Combustion modification through flue gas scrubbing

Energy Technology Data Exchange (ETDEWEB)

Watts, J.U. [Dept. of Energy, Pittsburgh, PA (United States). Federal Energy Technology Center; Savichky, W.J.; O`Dea, D.T. [New York State Electric and Gas Corp., Binghamton, NY (United States)

1997-12-31

Regeneration is a biological term for formation or creating anew. In the case of Milliken station, a species of steam generation (Tangentus coali) regeneration refers to refitting critical systems with the latest technological advances to reduce emissions while maintaining or improving performance. The plant has undergone a series of operations which provided anatomical changes as well as a face lift. Each of the two units were place in suspended animation (outage) to allow these changes to be made. The paper describes the project which includes retrofitting combustion systems, pulverizers, boiler liners, scrubbers, and control room. This retrofit is meant to increase thermal efficiency while reducing the formation of nitrogen oxides.

Numerical Simulation of Gas-Solid Two-Phase Flow for Four-Channels Pulverized Swirling Burner

Directory of Open Access Journals (Sweden)

Defu LI

2013-05-01

Full Text Available This article presents a mathematical model of cold gas-solid two-phase flow which is based on the cement rotary kiln in service. By altering the parameters of air supply system of four- channels pulverized burner, investigations are taken of that motion trajectory and particle distributions in the very turbulent field. The results show that motion trail of most particles in rotary kiln is a combination process of gradual diffusion and slow sedimentation; increasing internal flow velocity would aggravate coal particles to diffuse; external flow velocity should be controlled in a reasonable range.

Detailed model for practical pulverized coal furnaces and gasifiers

Energy Technology Data Exchange (ETDEWEB)

Philips, S.D.; Smoot, L.D.

1989-08-01

The need to improve efficiency and reduce pollutant emissions commercial furnaces has prompted energy companies to search for optimized operating conditions and improved designs in their fossil-fuel burning facilities. Historically, companies have relied on the use of empirical correlations and pilot-plant data to make decisions about operating conditions and design changes. The high cost of collecting data makes obtaining large amounts of data infeasible. The main objective of the data book is to provide a single source of detailed three-dimensional combustion and combustion-related data suitable for comprehensive combustion model evaluation. Five tasks were identified as requirements to achieve the main objective. First, identify the types of data needed to evaluate comprehensive combustion models, and establish criteria for selecting the data. Second, identify and document available three-dimensional combustion data related to pulverized coal combustion. Third, collect and evaluate three-dimensional data cases, and select suitable cases based on selection criteria. Fourth, organize the data sets into an easy-to-use format. Fifth, evaluate and interpret the nature and quality of the data base. 39 refs., 15 figs., 14 tabs.

A Pulverized Coal-Fired Boiler Optimized for Oxyfuel Combustion Technology

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Tomáš Dlouhý

2012-01-01

Full Text Available This paper presents the results of a study on modifying a pulverized coal-fired steam boiler in a 250 MWe power plant for oxygen combustion conditions. The entry point of the study is a boiler that was designed for standard air combustion. It has been proven that simply substituting air by oxygen as an oxidizer is not sufficient for maintaining a satisfactory operating mode, not even with flue gas recycling. Boiler design optimization aggregating modifications to the boiler’s dimensions, heating surfaces and recycled flue gas flow rate, and specification of a flue gas recycling extraction point is therefore necessary in order to achieve suitable conditions for oxygen combustion. Attention is given to reducing boiler leakage, to which external pre-combustion coal drying makes a major contribution. The optimization is carried out with regard to an overall power plant conception for which a decrease in efficiency due to CO2 separation is formulated.

Flat-flame burner studies of pulverized-coal combustion. Experimental results on char reactivity

Energy Technology Data Exchange (ETDEWEB)

Peck, R.E.; Shi, L.

1996-12-01

Structure of laminar, premixed pulverized-coal flames in a 1-D reactor has been studied with emphasis on char reactivity. A 1.1-meter-long tube furnace accommodated high-temperature environments and long residence times for the laminar flames produced by a flat-flame, coal-dust burner. Experiments were conducted at different operating conditions (fuel type/size, fuel-air ratio). Measurements included solid sample composition, major gas species and hydrocarbon species concentrations, and gas- and particle-phase line-of-sight temperatures at different axial locations in flames. Degree of char burnout increased with coal volatiles content and decreased with coal particle size. Combustion in furnace was in oxidizer-deficient environment and higher burnout was achieved as the fuel-air ratio neared stoichiometric. For 0-45 {mu}m particles most of the fixed carbon mass loss occurred within 5 cm of the furnace inlet, and char reaction was slow downstream due to low oxidizer concentrations. Fixed carbon consumption of the 45-90 {mu}m particles generally was slower than for the small particles. About 40%-80% of the fixed carbon was oxidized in the furnace. Primary volatiles mass loss occurred within the first 4.5 cm, and more than 90% of the volatiles were consumed in the flames. The flames stabilized in the furnace produced less CH{sub 4} and H{sub 2} in the burnt gas than similar unconfined flames. NO concentrations were found to decrease along the furnace and to increase with decreasing fuel/air ratio. Temperature measurement results showed that gas-phase temperatures were higher than solid-phase temperatures. Temperatures generally decreased with decreasing volatiles content and increased as the equivalence ratio approached one. The results can be used to interpret thermochemical processes occurring in pulverized-coal combustion. (au) 15 refs.

Pyrolysis of superfine pulverized coal. Part 3. Mechanisms of nitrogen-containing species formation

International Nuclear Information System (INIS)

Liu, Jiaxun; Jiang, Xiumin; Shen, Jun; Zhang, Hai

2015-01-01

Highlights: • NH 3 and NO formation mechanisms during superfine pulverized coal pyrolysis are investigated. • Influences of temperature, heating rate, particle size, atmosphere, and acid wash on the NH 3 and NO formation are analyzed. • Transformations of nitrogen-containing structures in coal/char during pyrolysis are recognized through XPS observation. • Relationships among nitrogen-containing gaseous species during pyrolysis are discussed. - Abstract: With more stringent regulations being implemented, elucidating the formation mechanisms of nitrogen-containing species during the initial pyrolysis step becomes important for developing new NO x control strategies. However, there is a lack of agreement on the origins of NO x precursors during coal pyrolysis, in spite of extensive investigations. Hence, it is important to achieve a more precise knowledge of the formation mechanisms of nitrogen-contain species during coal pyrolysis. In this paper, pyrolysis experiments of superfine pulverized coal were performed in a fixed bed at low heating rates. The influences of temperature, coal type, particle size and atmosphere on the NH 3 and NO evolution were discussed. There is a central theme to develop knowledge of the relationship between particle sizes and evolving behaviors of nitrogen-containing species. Furthermore, the catalytic role of inherent minerals in coal was proved to be effective on the partitioning of nitrogen during coal pyrolysis. In addition, the conversion pathways of heteroaromatic nitrogen structures in coal/char during pyrolysis were recognized through the X-ray photoelectron spectroscopy (XPS) analysis. Large quantities of pyridinic and quanternary nitrogen functionalities were formed during the thermal degradation. Finally, the relationships among the nitrogen-containing gaseous species during coal pyrolysis were discussed. In brief, a comprehensive picture of the volatile-nitrogen partitioning during coal pyrolysis is obtained in this

Simulation of a high-pressure water jet structure as an innovative tool for pulverizing copper ore in KGHM Polska Miedź S.A.

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Przemysław Józef Borkowski

2016-01-01

Full Text Available Effective comminution of copper ore for further processing during flotation is still a challenge, both as a technological problem as well as for the high energy costs of such processing.A high-pressure water jet is one alternative method of preparing copper ore for final flotation, causing distinct enlargement of the surface of micronized particles, which could be profitable for copper production.As a consequence of such innovative processing, particles of copper ore become micronized, ensuring grain fractions directly useful for flotation at the exit of the pulverizing apparatus (the hydro-jetting mill.The paper presents some results of simulation as well as describing an analysis of the phenomena occurring inside the high-pressure water and abrasive-water jets of specific structures, elaborated in the aspect of developing hybrid jets of maximum erosive efficiency, potentially useful for effective pulverization.

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

Energy Technology Data Exchange (ETDEWEB)

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

2010-05-15

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

Novel fragmentation model for pulverized coal particles gasification in low temperature air thermal plasma

Directory of Open Access Journals (Sweden)

Jovanović Rastko D.

2016-01-01

Full Text Available New system for start-up and flame support based on coal gasification by low temperature air thermal plasma is planned to supplement current heavy oil system in Serbian thermal power plants in order to decrease air pollutions emission and operational costs. Locally introduced plasma thermal energy heats up and ignites entrained coal particles, thus starting chain process which releases heat energy from gasified coal particles inside burner channel. Important stages during particle combustion, such as particle devolatilisation and char combustion, are described with satisfying accuracy in existing commercial CFD codes that are extensively used as powerful tool for pulverized coal combustion and gasification modeling. However, during plasma coal gasification, high plasma temperature induces strong thermal stresses inside interacting coal particles. These stresses lead to “thermal shock” and extensive particle fragmentation during which coal particles with initial size of 50-100 m disintegrate into fragments of at most 5-10 m. This intensifies volatile release by a factor 3-4 and substantially accelerates the oxidation of combustible matter. Particle fragmentation, due to its small size and thus limited influence on combustion process is commonly neglected in modelling. The main focus of this work is to suggest novel approach to pulverized coal gasification under high temperature conditions and to implement it into commercial comprehensive code ANSYS FLUENT 14.0. Proposed model was validated against experimental data obtained in newly built pilot scale D.C plasma burner test facility. Newly developed model showed very good agreement with experimental results with relative error less than 10%, while the standard built-in gasification model had error up to 25%.

Experimental and Numerical Investigation of Effect of Coal Rank on Burn-off Time in Pulverized Coal Combustion

OpenAIRE

Nozawa, Sohei; Wada, Nozomi; Matsushita, Yosuke; Yamamoto, Tsuyoshi; Omori, Motohira; Harada, Tatsuro

2012-01-01

Thermogravimetry (TG) for two different coal ranks, Loy Yang coal and Newlands coal, was carried out in an atmospheric air environment. Detailed parameters of the heterogeneous oxidation reaction for each coal rank were estimated by analyzing the TG results. Heat and mass transfer of a single pulverized coal particle that was heated at a constant temperature were numerically simulated. In this calculation, the decrease in the mass ratio caused by the oxidation reaction was considered. The num...

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

Energy Technology Data Exchange (ETDEWEB)

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

1992-03-01

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

Risk management of energy efficiency projects in the industry - sample plant for injecting pulverized coal into the blast furnaces

OpenAIRE

Jovanović Filip P.; Berić Ivana M.; Jovanović Petar M.; Jovanović Aca D.

2016-01-01

This paper analyses the applicability of well-known risk management methodologies in energy efficiency projects in the industry. The possibilities of application of the selected risk management methodology are demonstrated within the project of the plants for injecting pulverized coal into blast furnaces nos. 1 and 2, implemented by the company US STEEL SERBIA d.o.o. in Smederevo. The aim of the project was to increase energy efficiency through the reductio...

Controlling the Sn-C bonds content in SnO2@CNTs composite to form in situ pulverized structure for enhanced electrochemical kinetics.

Science.gov (United States)

Cheng, Yayi; Huang, Jianfeng; Qi, Hui; Cao, Liyun; Luo, Xiaomin; Li, Jiayin; Xu, Zhanwei; Yang, Jun

2017-12-07

The Sn-C bonding content between the SnO 2 and CNTs interface was controlled by the hydrothermal method and subsequent heat treatment. Electrochemical analysis found that the SnO 2 @CNTs with high Sn-C bonding content exhibited much higher capacity contribution from alloying and conversion reaction compared with the low content of Sn-C bonding even after 200 cycles. The high Sn-C bonding content enabled the SnO 2 nanoparticles to stabilize on the CNTs surface, realizing an in situ pulverization process of SnO 2 . The in situ pulverized structure was beneficial to maintain the close electrochemical contact of the working electrode during the long-term cycling and provide ultrafast transfer paths for lithium ions and electrons, which promoted the alloying and conversion reaction kinetics greatly. Therefore, the SnO 2 @CNTs composite with high Sn-C bonding content displayed highly reversible alloying and conversion reaction. It is believed that the composite could be used as a reference for design chemically bonded metal oxide/carbon composite anode materials in lithium-ion batteries.

PASSIVE CONTROL OF PARTICLE DISPERSION IN A PARTICLE-LADEN CIRCULAR JET USING ELLIPTIC CO-ANNULAR FLOW: A MEANS FOR IMPROVING UTILIZATION AND EMISSION REDUCTIONS IN PULVERIZED COAL BURNER

Energy Technology Data Exchange (ETDEWEB)

Ahsan R. Choudhuri

2003-06-01

A passive control technology utilizing elliptic co-flow to control the particle flinging and particle dispersion in a particle (coal)-laden flow was investigated using experimental and numerical techniques. Preferential concentration of particles occurs in particle-laden jets used in pulverized coal burner and causes uncontrollable NO{sub x} formation due to inhomogeneous local stoichiometry. This particular project was aimed at characterizing the near-field flow behavior of elliptic coaxial jets. The knowledge gained from the project will serve as the basis of further investigation on fluid-particle interactions in an asymmetric coaxial jet flow-field and thus is important to improve the design of pulverized coal burners where non-homogeneity of particle concentration causes increased NO{sub x} formation.

Analysis of Chemical Reaction Kinetics Behavior of Nitrogen Oxide During Air-staged Combustion in Pulverized Boiler

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Jun-Xia Zhang

2016-03-01

Full Text Available Because the air-staged combustion technology is one of the key technologies with low investment running costs and high emission reduction efficiency for the pulverized boiler, it is important to reveal the chemical reaction kinetics mechanism for developing various technologies of nitrogen oxide reduction emissions. At the present work, a three-dimensional mesh model of the large-scale four corner tangentially fired boiler furnace is established with the GAMBIT pre-processing of the FLUENT software. The partial turbulent premixed and diffusion flame was simulated for the air-staged combustion processing. Parameters distributions for the air-staged and no the air-staged were obtained, including in-furnace flow field, temperature field and nitrogen oxide concentration field. The results show that the air-staged has more regular velocity field, higher velocity of flue gas, higher turbulence intensity and more uniform temperature of flue gas. In addition, a lower negative pressure zone and lower O2 concentration zone is formed in the main combustion zone, which is conducive to the NO of fuel type reduced to N2, enhanced the effect of NOx reduction. Copyright © 2016 BCREC GROUP. All rights reserved Received: 5th November 2015; Revised: 14th January 2016; Accepted: 16th January 2016  How to Cite: Zhang, J.X., Zhang, J.F. (2016. Analysis of Chemical Reaction Kinetics Behavior of Nitrogen Oxide During Air-staged Combustion in Pulverized Boiler. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (1: 100-108. (doi:10.9767/bcrec.11.1.431.100-108 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.11.1.431.100-108

Reducing NOx Emissions for a 600 MWe Down-Fired Pulverized-Coal Utility Boiler by Applying a Novel Combustion System.

Science.gov (United States)

Ma, Lun; Fang, Qingyan; Lv, Dangzhen; Zhang, Cheng; Chen, Yiping; Chen, Gang; Duan, Xuenong; Wang, Xihuan

2015-11-03

A novel combustion system was applied to a 600 MWe Foster Wheeler (FW) down-fired pulverized-coal utility boiler to solve high NOx emissions, without causing an obvious increase in the carbon content of fly ash. The unit included moving fuel-lean nozzles from the arches to the front/rear walls and rearranging staged air as well as introducing separated overfire air (SOFA). Numerical simulations were carried out under the original and novel combustion systems to evaluate the performance of combustion and NOx emissions in the furnace. The simulated results were found to be in good agreement with the in situ measurements. The novel combustion system enlarged the recirculation zones below the arches, thereby strengthening the combustion stability considerably. The coal/air downward penetration depth was markedly extended, and the pulverized-coal travel path in the lower furnace significantly increased, which contributed to the burnout degree. The introduction of SOFA resulted in a low-oxygen and strong-reducing atmosphere in the lower furnace region to reduce NOx emissions evidently. The industrial measurements showed that NOx emissions at full load decreased significantly by 50%, from 1501 mg/m3 (O2 at 6%) to 751 mg/m3 (O2 at 6%). The carbon content in the fly ash increased only slightly, from 4.13 to 4.30%.

Gasification in pulverized coal flames. Final report (Part I). Pulverized coal combustion and gasification in a cyclone reactor: experiment and model

Energy Technology Data Exchange (ETDEWEB)

Barnhart, J. S.; Laurendeau, N. M.

1979-05-01

A unified experimental and analytical study of pulverized coal combustion and low-BTU gasification in an atmospheric cyclone reactor was performed. Experimental results include several series of coal combustion tests and a coal gasification test carried out via fuel-rich combustion without steam addition. Reactor stability was excellent over a range of equivalence ratios from .67 to 2.4 and air flowrates from 60 to 220 lb/hr. Typical carbon efficiencies were 95% for air-rich and stoichiometric tests and 80% for gasification tests. The best gasification results were achieved at an equivalence ratio of 2.0, where the carbon, cold gas and hot gas efficiencies were 83, 45 and 75%, respectively. The corresponding product gas heating value was 70 BTU/scf. A macroscopic model of coal combustion in the cyclone has been developed. Fuel-rich gasification can also be modeled through a gas-phase equilibrium treatment. Fluid mechanics are modeled by a particle force balance and a series combination of a perfectly stirred reactor and a plug flow reactor. Kinetic treatments of coal pyrolysis, char oxidation and carbon monoxide oxidation are included. Gas composition and temperature are checked against equilibrium values. The model predicts carbon efficiency, gas composition and temperature and reactor heat loss; gasification parameters, such as cold and hot gas efficiency and make gas heating value, are calculated for fuel-rich conditions. Good agreement exists between experiment and theory for conditions of this investigation.

Numerical analysis of loads effect on combustion performance and NO{sub x} emissions of a 220 MW pulverized coal boiler

Energy Technology Data Exchange (ETDEWEB)

Li, Jun; Yang, Weihong; Blasiak, Wlodzimierz [Royal Institute of Technology (KTH), Stockholm (Sweden). Div. of Energy and Furnace Technology; Jankowski, Radoslaw; Kotecki, Michal; Szewczyk, Dariusz [Industrial Combustion Systems (ICS) Company, Poznan (Poland); Brzdekiewicz, Artur [Remak-Rozruch SA, Opole (Poland)

2013-07-01

This paper presents numerical study on the combustion performance and NO{sub x} emissions of a 220 MW pulverized coal boiler. Three different loads have been simulated with combusting coal, 200, 170 and 140 MW, respectively. In order to get as precise as possible numerical analysis results, two-step simulation method has been adopted in this work, namely, air supply system simulation and furnace simulation. After air supply system simulation, the results have been taken as the initial and boundary conditions for furnace simulation. The comparison between the measured values and predicted results from 200 MW case shows much better agreement. According to the simulation results, the adopted two-step simulation method is reasonable and suitable for predicting the characters of the flow and combustion process. It is concluded that the distributions of temperature, O{sub 2} and CO concentration inside furnace with different loads shows good similarly. The total NOx emissions decreased with the boiler load reducing, and fuel NO{sub x} has the same trend as total NO{sub x}, and fuel NO{sub x} account for about 66% in total NO{sub x} in all the three cases. More important, thermal NO{sub x} slowly decreased with the rise of boiler load. More detailed results presented in this paper enhance the understanding of combustion processes and complex flow patterns of front-wall pulverized coal boilers.

Achievement report for fiscal 1999 on project for supporting the formation of energy/environmental technology verification project. International joint verification research project (Verification project relative to ignition and NOx reduction using plasma sub-burner in pulverized coal-fired furnace); 1999 nendo plasma sabubana ni yoru bifuntan nenshoro ni okeru chakka oyobi NO{sub x} teigen gijutsu ni kansuru jissho project seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

This project is executed through the cooperation of a Russian research institute, Akita Prefectural University, and the Ishikawajima-Harima Heavy Industries Co., Ltd. In the development of a plasma sub-burner and the basic research for its verification, a pulverized coal burning plasma sub-burner is designed and fabricated, a basic burning experiment is conducted for the plasma sub-burner, and plasma stabilization in a pulverized coal flow is simulated. In the verification study of the ignition by the plasma sub-burner in a pulverized coal-fired furnace, it is found that the newly-developed plasma sub-burner satisfies the prescribed operating conditions in the system and that the ignition of pulverized coal takes place across the air ratio range of 0.5-1.5 when pulverized coal is fed to the sub-burner. It is also found that NOx is reduced a great deal when a plasma operating on an orifice gas of air or nitrogen is generated in a gas which contains NOx. (NEDO)

Physicochemical characterization of pulverized phyllite rocks to geopolymer resin synthesis

Energy Technology Data Exchange (ETDEWEB)

Melo, L.G.A. [Instituto Militar de Enegenharia (IME), Rio de Janeiro, RJ (Brazil); Pires, E.F.C. [Universidade Federal Fluminense (UFF), Niteroi, RJ (Brazil); Pereira, R.A.; Silva, F.J. [Instituto Federal de Educacao, Ciencia e Tecnologia do Rio de Raneiro (IFRJ), RJ (Brazil)

2016-07-01

Full text: Geopolymeric materials have common properties considered unique, such as: early-high compressive strength, durability, high chemical resistance to acids and sulfates attacks, ability to immobilize toxic and radioactive compounds, low porosity, low permeability, and resistance to high temperatures. Together with its environmental benefits, such as low energy consumption and low carbon dioxide emissions during production, these inorganic polymers are strategic materials for sustainable development and a good alternative to Portland cement. The main objective for introducing alternative materials is to lower the associated costs of its industrial process. Thus, the use of phyllite as the geopolymer precursor, is encouraged by its abundance, low cost, and the fact that it already is applied to the ceramic industries as kaolin substitute. This paper presents a physical characterization using TEM, SEM, XRD and XRF techniques of two pulverized phyllite rocks used as geopolymer precursors for refractory applications. It was found that both phyllite rocks studied have a high quartz content of approximately 50% that can be explored as 'filler' function in the microstructure, which stabilizes residual tensions after curing. Kaolinite and muscovite minerals are present up to 40% and are responsible for the high strengths in the geopolymer resins, as determined by compressive strength tests. (author)

Effect of the Reburning Zone Stoichiometry on the Nox Concentration at the Three-Stage Combustion of Pulverized Coal

Directory of Open Access Journals (Sweden)

Chernetskaya Nelya

2016-01-01

Full Text Available Numerical study of heat and mass transfer taking into account the combustion of coal particles in the furnace at the three-stage combustion of pulverized coal was performed. Analysis of the reburning zone stoichiometry on the concentration of nitrogen oxides at the furnace outlet was made. The values of excess air in the primary and reburning combustion zones, providing for the concentration of nitrogen oxides at the furnace outlet is not more than 350 mg/m3 and unburned carbon not more than 1 % when burning coal with a high content of nitrogen were established.

Quality and environmental aspects in relation to the application of pulverized fuel ash

International Nuclear Information System (INIS)

Berg, J.W. van den

1991-01-01

In the Netherlands pulverised coal from different parts of the world is used in 5 coalfired power stations which each have 1 to 3 boilers, which in turn are equipped with various types of burners. This causes a large variation in the composition of the pulverized fuel ash (PFA). The PFA is marketed in several areas, each of which has its own specific quality requirements. These requirements are partially dictated in standard specifications. In order to obtain insight into the quality of the PFA, samples are taken and analysed daily. Rules for certification, concerning the quality and the quality control of PFA for use in concrete in The Netherlands have been agreed upon. The environmental aspects in relation to the application of PFA concern the working conditions and health aspects during processing and the environmental impact when PFA is used as a building material. The Dutch legislation concerning the environmental consequences of the application of PFA and other secondary materials is currently under review. 3 tabs

The application of RANS CFD for design of SNCR technology for a pulverized coal-fired boiler

Directory of Open Access Journals (Sweden)

Ruszak Monika

2017-06-01

Full Text Available The article describes the technology of NOx emission abatement by SNCR method. The scope of research included CDF simulations as well as design and construction of the pilot plant and tests of NOx reduction by urea in the plant located in industrial pulverized-coal fired boiler. The key step of research was to determine the appropriate temperature window for the SNCR process. The proposed solution of the location of injection lances in the combustion chamber enabled to achieve over a 30% reduction of NOx. It is possible to achieve higher effectiveness of the proposed SNCR technology and meet the required emission standards via providing prior reduction of NOx to the level of 350 mg/um3 using the primary methods.

EXPERIMENTS AND COMPUTATIONAL MODELING OF PULVERIZED-COAL IGNITION; FINAL

International Nuclear Information System (INIS)

Samuel Owusu-Ofori; John C. Chen

1999-01-01

Under typical conditions of pulverized-coal combustion, which is characterized by fine particles heated at very high rates, there is currently a lack of certainty regarding the ignition mechanism of bituminous and lower rank coals as well as the ignition rate of reaction. furthermore, there have been no previous studies aimed at examining these factors under various experimental conditions, such as particle size, oxygen concentration, and heating rate. Finally, there is a need to improve current mathematical models of ignition to realistically and accurately depict the particle-to-particle variations that exist within a coal sample. Such a model is needed to extract useful reaction parameters from ignition studies, and to interpret ignition data in a more meaningful way. The authors propose to examine fundamental aspects of coal ignition through (1) experiments to determine the ignition temperature of various coals by direct measurement, and (2) modeling of the ignition process to derive rate constants and to provide a more insightful interpretation of data from ignition experiments. The authors propose to use a novel laser-based ignition experiment to achieve their first objective. Laser-ignition experiments offer the distinct advantage of easy optical access to the particles because of the absence of a furnace or radiating walls, and thus permit direct observation and particle temperature measurement. The ignition temperature of different coals under various experimental conditions can therefore be easily determined by direct measurement using two-color pyrometry. The ignition rate-constants, when the ignition occurs heterogeneously, and the particle heating rates will both be determined from analyses based on these measurements

Examination of flame length for burning pulverized coal in laminar flow reactor

Energy Technology Data Exchange (ETDEWEB)

Kim, Jae Dong; Kim, Gyu Bo; Chang, Young June; Song, Ju Hun; Jeon, Chung Hwan [Pusan National University, Busan (Korea, Republic of)

2010-12-15

Because there has been a recent increase in the use of low calorific coal compared to standard coal, it is crucial to control the char flame length governing the burning life-time of coal in a coal-fired utility boiler. The main objective of this study is to develop a simplified model that can theoretically predict the flame length for burning coal in a laboratory-scale entrained laminar flow reactor (LFR) system. The char burning behavior was experimentally observed when sub-bituminous pulverized coal was fed into the LFR under burning conditions similar to those in a real boiler: a heating rate of 1000 K/s, an oxygen molar fraction of 7.7 %, and reacting flue gas temperatures ranging from 1500 to 2000 K. By using the theoretical model developed in this study, the effect of particle size on the coal flame length was exclusively addressed. In this model, the effect of particle mass was eliminated to compare with the experimental result performed under a constant mass feeding of coal. Overall, the computed results for the coal flame length were in good agreement with the experimental data, particularly when the external oxygen diffusion effect was considered in the model

Examination of flame length for burning pulverized coal in laminar flow reactor

International Nuclear Information System (INIS)

Kim, Jae Dong; Kim, Gyu Bo; Chang, Young June; Song, Ju Hun; Jeon, Chung Hwan

2010-01-01

Because there has been a recent increase in the use of low calorific coal compared to standard coal, it is crucial to control the char flame length governing the burning life-time of coal in a coal-fired utility boiler. The main objective of this study is to develop a simplified model that can theoretically predict the flame length for burning coal in a laboratory-scale entrained laminar flow reactor (LFR) system. The char burning behavior was experimentally observed when sub-bituminous pulverized coal was fed into the LFR under burning conditions similar to those in a real boiler: a heating rate of 1000 K/s, an oxygen molar fraction of 7.7 %, and reacting flue gas temperatures ranging from 1500 to 2000 K. By using the theoretical model developed in this study, the effect of particle size on the coal flame length was exclusively addressed. In this model, the effect of particle mass was eliminated to compare with the experimental result performed under a constant mass feeding of coal. Overall, the computed results for the coal flame length were in good agreement with the experimental data, particularly when the external oxygen diffusion effect was considered in the model

Experimental investigation on NO{sub x} emission and carbon burnout from a radially biased pulverized coal whirl burner

Energy Technology Data Exchange (ETDEWEB)

Xue, Shan; Hui, Shi' en; Zhou, Qulan; Xu, Tongmo; Hu, Hongli [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Liu, Taisheng [Dongfang Boiler Group Co., Ltd., Zigong, Sichuan 643001 (China)

2009-09-15

Experiments have been performed on 1 MW pulverized coal (pc) furnace in order to investigate the characteristics of coal combustion and NO{sub x} emission from a new type of radially biased dual register whirl burner. The burner is characterized by a primary air pipe with a continuously changing cross-section and an impact ring. The mixture of pulverized coal and air inside the primary pipe is split into two streams, which are the outer pc rich annular jet and the inner pc lean annular jet respectively. Three Chinese coals, which are high rank bituminous coal, low rank bituminous coal and meager coal respectively, are used in the experiments. We examine the influences of various parameters such as the relative position of the over-fire air (OFA) nozzle, over-fire air ratio (19.1%), primary air ratio, inner secondary air ratio, outer secondary air ratio, inner secondary air swirling intensity, and outer secondary air swirling intensity on NO{sub x} formation and unburned carbon in fly ash. With the primary air ratio increasing from 13.4% to 23.4%, the value of the NO{sub x} emission of the SH coal decreases by 26.7% at first, and then increases by 21.7%. In contrast, the value of the carbon in fly ash (C{sub FA}) increases by 40.1% at first, and then decreases by 58.3%. According to the experimental results, the influence of each individual parameter on NO{sub x} formation and unburned carbon in fly ash agrees well with the existing literature. In this study, the influences of various combinations of these parameters are also examined, thus providing some reference for the design of the radial biased whirl burner, the configuration of the furnace and the distribution of the air. (author)

Mesoporous Silicon Sponge as an Anti-Pulverization Structure for High-Performance Lithium-ion Battery Anodes

Energy Technology Data Exchange (ETDEWEB)

Li, Xiaolin; Gu, Meng; Hu, Shenyang Y.; Kennard, Rhiannon; Yan, Pengfei; Chen, Xilin; Wang, Chong M.; Sailor, Michael J.; Zhang, Jiguang; Liu, Jun

2014-07-08

Nanostructured silicon is a promising anode material for high performance lithium-ion batteries, yet scalable synthesis of such materials, and retaining good cycling stability in high loading electrode remain significant challenges. Here, we combine in-situ transmission electron microscopy and continuum media mechanical calculations to demonstrate that large (>20 micron) mesoporous silicon sponge (MSS) prepared by the scalable anodization method can eliminate the pulverization of the conventional bulk silicon and limit particle volume expansion at full lithiation to ~30% instead of ~300% as observed in bulk silicon particles. The MSS can deliver a capacity of ~750 mAh/g based on the total electrode weight with >80% capacity retention over 1000 cycles. The first-cycle irreversible capacity loss of pre-lithiated MSS based anode is only <5%. The insight obtained from MSS also provides guidance for the design of other materials that may experience large volume variation during operations.

Enhanced Combustion Low NOx Pulverized Coal Burner

Energy Technology Data Exchange (ETDEWEB)

David Towle; Richard Donais; Todd Hellewell; Robert Lewis; Robert Schrecengost

2007-06-30

For more than two decades, Alstom Power Inc. (Alstom) has developed a range of low cost, infurnace technologies for NOx emissions control for the domestic U.S. pulverized coal fired boiler market. This includes Alstom's internally developed TFS 2000{trademark} firing system, and various enhancements to it developed in concert with the U.S. Department of Energy. As of the date of this report, more than 270 units representing approximately 80,000 MWe of domestic coal fired capacity have been retrofit with Alstom low NOx technology. Best of class emissions range from 0.18 lb/MMBtu for bituminous coal to 0.10 lb/MMBtu for subbituminous coal, with typical levels at 0.24 lb/MMBtu and 0.13 lb/MMBtu, respectively. Despite these gains, NOx emissions limits in the U.S. continue to ratchet down for new and existing boiler equipment. On March 10, 2005, the Environmental Protection Agency (EPA) announced the Clean Air Interstate Rule (CAIR). CAIR requires 25 Eastern states to reduce NOx emissions from the power generation sector by 1.7 million tons in 2009 and 2.0 million tons by 2015. Low cost solutions to meet such regulations, and in particular those that can avoid the need for a costly selective catalytic reduction system (SCR), provide a strong incentive to continue to improve low NOx firing system technology to meet current and anticipated NOx control regulations. The overall objective of the work is to develop an enhanced combustion, low NOx pulverized coal burner, which, when integrated with Alstom's state-of-the-art, globally air staged low NOx firing systems will provide a means to achieve: Less than 0.15 lb/MMBtu NOx emissions when firing a high volatile Eastern or Western bituminous coal, Less than 0.10 lb/MMBtu NOx emissions when firing a subbituminous coal, NOx reduction costs at least 25% lower than the costs of an SCR, Validation of the NOx control technology developed through large (15 MWt) pilot scale demonstration, and Documentation required for

Effect of the parameters of a straight-through pulverized coal spray on formation of nitrogen oxides

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.

1987-04-01

Experiments were conducted on varying the parameters affecting intensity of the mixing process at the starting point of a pulverized coal spray. Investigations were carried out using Donetsk black coal in a BKZ-210-140FZhSh steam generator equipped with a tangential combustion chamber. The plant featured liquid slag removal and direct blow-in as well as a medium-speed model VSM-140 mill. Four experiments were conducted in which gas samples were taken from the combustion chamber and analyzed for RO/sub 2/ and O/sub 2/ as well as CO and H/sub 2/. A relationship between reducing gases at the starting point of the torch and the initial air feed factor was demonstrated. Experiments were conducted to determine a relationship between NO/sub x/ concentrations in exhaust gases and the initial air feed factor. 5 refs.

Assessment of ecotoxicological risks of element leaching from pulverized coal ashes

International Nuclear Information System (INIS)

Jenner, H.A.

1995-05-01

The main objective of this study was to assess the effects on representative organisms, after exposure to pulverized fuel ashes (PFA) or leachates of PFA. The studies dealt primarily with toxic effects and focused on the impact of PFA on single species and groups of related species including their acute effects, bioconcentration and ultimate body burden. Emphasis was placed on reproductive effects in this study. Crawling behaviour of mussels was also studied to reflection to the physical differences of PFA from other substrates. A newly developed device was therefore used for valve movement monitoring. A phytomonitoring system with duckweed was developed for assessing effects on yield, using image processing. The results are presented in three parts according to the environmental compartments concerned i.e. marine, freshwater and terrestrial. In Part 1, marine studies with benthic invertebrates were carried out in model ecosystems with different compositions of PFA and Waddensea sediment. In Part 2, the freshwater studies were carried out in flow chambers using the painters mussel Unio pictorum. Besides behavioural studies with PFA specific research was carried out with selenium on body burden and effects on reproduction. Selenium is a prominent constituent of PFA. In Part 3 research is described on the monitoring of leachates of PFA with duckweed. A separate chapter deals with growth, mortality and accumulation in plants and worms exposed to coal gasification slag. figs., tabs., refs

Pressing device for producing compacts from source material in powder form in particular pulverized nuclear reactor fuel

International Nuclear Information System (INIS)

Heller, G.; Adelmann, M.; Konigs, W.; Wendorf, W.

1984-01-01

Pressing device for producing compacts from source material in powder form, in particular pulverized nuclear reactor fuel having a die-plate contained in platen and a bore associated with a ram, for receiving source material powder, a filling shoe, and a reservoir for powder connected by a hose to the filling shoe. The device is characterized by a passing wheel in the filling shoe as filling aid means; a tube containing a feedscrew disposed between the reservoir and hose as metering means; the reservoir having a bottom part with a can type place-on part with an opening eccentric to the axis; a coupling part and a cover part are placed on the open part of the can, these parts are also provided with a passageway to the feedscrew eccentric to the longitudinal axis

A simple numerical model to estimate the effect of coal selection on pulverized fuel burnout

Energy Technology Data Exchange (ETDEWEB)

Sun, J.K.; Hurt, R.H.; Niksa, S.; Muzio, L.; Mehta, A.; Stallings, J. [Brown University, Providence, RI (USA). Division Engineering

2003-06-01

The amount of unburned carbon in ash is an important performance characteristic in commercial boilers fired with pulverized coal. Unburned carbon levels are known to be sensitive to fuel selection, and there is great interest in methods of estimating the burnout propensity of coals based on proximate and ultimate analysis - the only fuel properties readily available to utility practitioners. A simple numerical model is described that is specifically designed to estimate the effects of coal selection on burnout in a way that is useful for commercial coal screening. The model is based on a highly idealized description of the combustion chamber but employs detailed descriptions of the fundamental fuel transformations. The model is validated against data from laboratory and pilot-scale combustors burning a range of international coals, and then against data obtained from full-scale units during periods of coal switching. The validated model form is then used in a series of sensitivity studies to explore the role of various individual fuel properties that influence burnout.

Computational Fluid Dynamics (CFD) Modeling for High Rate Pulverized Coal Injection (PCI) to Blast Furnaces

International Nuclear Information System (INIS)

Zhou, Chenn

2008-01-01

Pulverized coal injection (PCI) into the blast furnace (BF) has been recognized as an effective way to decrease the coke and total energy consumption along with minimization of environmental impacts. However, increasing the amount of coal injected into the BF is currently limited by the lack of knowledge of some issues related to the process. It is therefore important to understand the complex physical and chemical phenomena in the PCI process. Due to the difficulty in attaining trus BF measurements, Computational fluid dynamics (CFD) modeling has been identified as a useful technology to provide such knowledge. CFD simulation is powerful for providing detailed information on flow properties and performing parametric studies for process design and optimization. In this project, comprehensive 3-D CFD models have been developed to simulate the PCI process under actual furnace conditions. These models provide raceway size and flow property distributions. The results have provided guidance for optimizing the PCI process

Pulverized coal burnout in blast furnace simulated by a drop tube furnace

Energy Technology Data Exchange (ETDEWEB)

Du, Shan-Wen [Steel and Aluminum Research and Development Department, China Steel Corporation, Kaohsiung 812 (China); Chen, Wei-Hsin [Department of Greenergy, National University of Tainan, Tainan 700 (China); Lucas, John A. [School of Engineering of the University of Newcastle, Callaghan, NSW 2308 (Australia)

2010-02-15

Reactions of pulverized coal injection (PCI) in a blast furnace were simulated using a drop tube furnace (DTF) to investigate the burnout behavior of a number of coals and coal blends. For the coals with the fuel ratio ranging from 1.36 to 6.22, the experimental results indicated that the burnout increased with decreasing the fuel ratio, except for certain coals departing from the general trend. One of the coals with the fuel ratio of 6.22 has shown its merit in combustion, implying that the blending ratio of the coal in PCI operation can be raised for a higher coke replacement ratio. The experiments also suggested that increasing blast temperature was an efficient countermeasure for promoting the combustibility of the injected coals. Higher fuel burnout could be achieved when the particle size of coal was reduced from 60-100 to 100-200 mesh. However, once the size of the tested coals was in the range of 200 and 325 mesh, the burnout could not be improved further, resulting from the agglomeration of fine particles. Considering coal blend reactions, the blending ratio of coals in PCI may be adjusted by the individual coal burnout rather than by the fuel ratio. (author)

Exergetic and environmental analysis of a pulverized coal power plant

International Nuclear Information System (INIS)

Restrepo, Álvaro; Miyake, Raphael; Kleveston, Fábio; Bazzo, Edson

2012-01-01

This paper presents the results of exergetic and environmental analysis of a typical pulverized coal power plant located in Brazil. The goal was to quantify both the exergy destruction and the environmental impact associated with a thermal power plant. The problem boundary consists of the entire coal delivery route, including mining and beneficiation, transport, pre-burning processes and the power plant. The used data were obtained mainly from field measurements taken in all system processes, from mining to the power plant. The study focused only on the operation period. Previous works have shown that the construction and decommissioning periods contribute less than 1% of the environmental impact. The exergetic analysis was based on the second law of thermodynamics while the environmental analysis was based on life cycle assessment (LCA) using SimaPro 7.2, focussing on the climate change and acidification impact categories. The CO 2 -eq emission was 1300 kg per MWh. The highest degree of environmental impact occurred during the combustion process. The exergetic and environmental analysis provides a tool to evaluate irreversibilities and the environmental impact, identifying the most significant stages and equipment of the entire power generation process. -- Highlights: ► Exergetic and environmental analysis of a typical Brazilian PC power plant. ► Environmental impact associated with the mining, transport and thermal power plant. ► Life cycle assessment used for environmental analysis. ► Acidification impact category evaluated using Eco-indicator 99. ► Climate change impact evaluation using (Global Warming Potential) GWP 100a.

CFD modelling and analysis of pulverized coal injection in blast furnace: an overview

Energy Technology Data Exchange (ETDEWEB)

Shen, Yansong; Yu, Aibing [Laboratory for Simulation and Modelling of Particulate Systems, School of Materials Science and Engineering, The University of New South Wales (UNSW), Sydney, NSW 2052 (Australia); Zulli, Paul [BlueScope Steel Research (BSR), P.O. Box 202, Port Kembla, NSW 2505 (Australia)

2011-05-15

In order to understand the complicated phenomena of pulverized coal injection (PCI) process in blast furnace (BF), several mathematical models have been developed by the UNSW and BSR cooperation. These models are featuring from coal combustion in a pilot-scale test rig, to coal combustion in a real BF, and then to coal/coke combustion in a real BF, respectively. This paper reviews these PCI models in aspects of model developments and model applicability. The model development is firstly discussed in terms of model formulation, their new features and geometry/regions considered. The model applicability is then discussed in terms of main findings followed by the model evaluation on their advantages and limitations. It is indicated that the three PCI models are all able to describe PCI operation qualitatively. The model of coal/coke combustion in a real BF is more reliable for simulating in-furnace phenomena of PCI operation qualitatively and quantitatively. Such model gives a more reliable burnout prediction over the raceway surface, which could better represent the amount of unburnt char entering the coke bed. These models are useful for understanding the flow-thermo-chemical behaviours and then optimising the PCI operation in practice. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Report on 1980 result of R and D under Sunshine Project. Development of solvent extraction liquefaction technology and demonstrative investigation on development of brown coal liquefaction technology (studies on high-temperature in-oil pulverization); 1980 nendo yozai chushutsu ekika gijutsu no kaihatsu / kattan ekika gijutsu kaihatsu jissho chosa seika hokokusho. Koon'yuchu funsai no kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1981-03-01

This paper explains the results of development of coal liquefaction technology under the Sunshine Project in fiscal 1980. As a part of the development of brown coal liquefaction technology, pulverization of the first-dehydration brown coal was technologically established, as were adjustment of slurry and equipment for the second-dehydration process. A 20kg/h high temperature in-oil pulverizer was designed, constructed and made ready for the studies. A high temperature mill was a wet type ball mill, 500mm{phi}(diameter) x 1,500 mm length and 2.2kw. Coal was fully pulverized even in a solvent such as creosote oil and anthracene oil freed from crystal, and was adjustable to a prescribed particle size distribution. The wet type slurry adjustment method offered prospects that solvent/coal slurry moisture could be controlled to a prescribed value. An analysis was made on the mill outlet gas and drain collection liquid at the time of high temperature in-oil pulverization, which provided knowledge of securing safety. An analysis was also made on the influence of the heating temperature rise of the mill on the strength, which provided basic data for examining the strength of the mill. Using brown coal as the raw material, slurry was prepared, which confirmed that the device had functions as planned. (NEDO)

Influence of staged-air on airflow, combustion characteristics and NO(x) emissions of a down-fired pulverized-coal 300 MW(e) utility boiler with direct flow split burners.

Science.gov (United States)

Li, Zhengqi; Kuang, Min; Zhang, Jia; Han, Yunfeng; Zhu, Qunyi; Yang, Lianjie; Kong, Weiguang

2010-02-01

Cold airflow experiments were conducted to investigate the aerodynamic field in a small-scale furnace of a down-fired pulverized-coal 300 MW(e) utility boiler arranged with direct flow split burners enriched by cyclones. By increasing the staged-air ratio, a deflected flow field appeared in the lower furnace; larger staged-air ratios produced larger deflections. Industrial-sized experiments on a full-scale boiler were also performed at different staged-air damper openings with measurements taken of gas temperatures in the burner region and near the right-side wall, wall heat fluxes, and gas components (O(2), CO, and NO(x)) in the near-wall region. Combustion was unstable at staged-air damper openings below 30%. For openings of 30% and 40%, late ignition of the pulverized coal developed and large differences arose in gas temperatures and heat fluxes between the regions near the front and rear walls. In conjunction, carbon content in the fly ash was high and boiler efficiency was low with high NO(x) emission above 1200 mg/m(3) (at 6% O(2) dry). For fully open dampers, differences in gas temperatures and heat fluxes, carbon in fly ash and NO(x) emission decreased yielding an increase in boiler efficiency. The optimal setting is fully open staged-air dampers.

DEVELOPMENT OF A NOVEL RADIATIVELY/CONDUCTIVELY STABILIZED BURNER FOR SIGNIFICANT REDUCTION OF NOx EMISSIONS AND FOR ADVANCING THE MODELING AND UNDERSTANDING OF PULVERIZED COAL COMBUSTION AND EMISSIONS

Energy Technology Data Exchange (ETDEWEB)

Noam Lior; Stuart W. Churchill

2003-10-01

The primary objective of the proposed study was the study and analysis of, and design recommendations for, a novel radiatively-conductively stabilized combustion (RCSC) process for pulverized coal, which, based on our prior studies with both fluid fuels and pulverized coal, holds a high promise to reduce NO{sub x} production significantly. We have primarily engaged in continuing and improving our process modeling and analysis, obtained a large amount of quantitative information about the effects of the major parameters on NO{sub x} production, conducted an extensive exergy analysis of the process, evaluated the practicalities of employing the Radiatively-Conductively Stabilized Combustor (RCSC) to large power and heat plants, and improved the experimental facility. Prior experimental work has proven the feasibility of the combustor, but slagging during coal combustion was observed and should be dealt with. The primary outcomes and conclusions from the study are: (1) we developed a model and computer program that represents the pulverized coal combustion in the RCSC, (2) the model predicts that NO{sub x} emissions can be reduced by a number of methods, detailed in the report. (3) the exergy analysis points out at least a couple of possible ways to improve the exergetic efficiency in this combustor: increasing the effectiveness of thermal feedback, and adjusting the combustor mixture exit location, (4) because of the low coal flow rates necessitated in this study to obtain complete combustion in the burner, the size of a burner operating under the considered conditions would have to be up to an order of magnitude, larger than comparable commercial burners, but different flow configurations of the RCSC can yield higher feed rates and smaller dimensions, and should be investigated. Related to this contract, eleven papers were published in journals and conference proceedings, and ten invited presentations were given at university and research institutions, as well as at

Weighted sum of gray gases model optimization for numerical investigations of processes inside pulverized coal-fired furnaces

Science.gov (United States)

Crnomarkovic, Nenad; Belosevic, Srdjan; Tomanovic, Ivan; Milicevic, Aleksandar

2017-12-01

The effects of the number of significant figures (NSF) in the interpolation polynomial coefficients (IPCs) of the weighted sum of gray gases model (WSGM) on results of numerical investigations and WSGM optimization were investigated. The investigation was conducted using numerical simulations of the processes inside a pulverized coal-fired furnace. The radiative properties of the gas phase were determined using the simple gray gas model (SG), two-term WSGM (W2), and three-term WSGM (W3). Ten sets of the IPCs with the same NSF were formed for every weighting coefficient in both W2 and W3. The average and maximal relative difference values of the flame temperatures, wall temperatures, and wall heat fluxes were determined. The investigation showed that the results of numerical investigations were affected by the NSF unless it exceeded certain value. The increase in the NSF did not necessarily lead to WSGM optimization. The combination of the NSF (CNSF) was the necessary requirement for WSGM optimization.

Determining the radiative properties of pulverized-coal particles from experiments. Final report

Energy Technology Data Exchange (ETDEWEB)

Menguec, M.P.

1992-02-01

A comprehensive coupled experimental-theoretical study has been performed to determine the effective radiative properties of pulverized-coal/char particles. The results obtained show that the ``effective`` scattering phase function of coal particles are highly forward scattering and show less sensitivity to the size than predicted from the Lorenz-Mie theory. The main reason for this is the presence of smaller size particles associated with each larger particle. Also, the coal/char particle clouds display more side scattering than predicted for the same size range spheres, indicating the irregular shape of the particles and fragmentation. In addition to these, it was observed that in the visible wavelength range the coal absorption is not gray, and slightly vary with the wavelength. These two experimental approaches followed in this study are unique in a sense that the physics of the problem are not approximated. The properties determined include all uncertainties related to the particle shape, size distribution, inhomogeneity and spectral complex index of refraction data. In order to obtain radiative property data over a wider wavelength spectrum, additional ex-situ experiments have been carried out using a Fourier Transform Infrared (FT-IR) Spectrometer. The spectral measurements were performed over the wavelength range of 2 to 22 {mu}m. These results were interpreted to obtain the ``effective`` efficiency factors of coal particles and the corresponding refractive index values. The results clearly show that the coal/char radiative properties display significant wavelength dependency in the infrared spectrum.

An internal magnetic field strategy to reuse pulverized active materials for high performance: a magnetic three-dimensional ordered macroporous TiO2/CoPt/α-Fe2O3 nanocomposite anode.

Science.gov (United States)

Tang, Yiping; Hong, Liang; Li, Jiquan; Hou, Guangya; Cao, Huazhen; Wu, Liankui; Zheng, Guoqu; Wu, Qingliu

2017-05-09

A ferromagnetic three-dimensional ordered macroporous TiO 2 /CoPt/α-Fe 2 O 3 (3DOMTCF) nanocomposite was synthesized via a sol-gel approach templated by poly(methyl methacrylate) (PMMA) microspheres. After magnetization, it exhibited an extremely high reversible capacity and a long cycle life, which were ascribed to the internal magnetic field for reusing pulverized active materials and its unique structure.

Numerical study of furnace process of a 600 MW pulverized coal boiler under low load with SNCR application

Energy Technology Data Exchange (ETDEWEB)

Cao, Q.X.; Shi, Y.; Liu, H.; Yang, C.H.; Wu, S.H. [Harbin Institute of Technology, Harbin (China)

2013-07-01

Numerical simulation of flow, heat transfer, and combustion process in a 600MW pulverized coal boiler under low load is performed using Computational Fluid Dynamics (CFD) code Fluent. The distributions of temperature and species were obtained and their influences on Selective non-catalytic reduction (SNCR) were analyzed. The results indicate that the furnace temperature changed significantly as the operation load declines. The furnace space with proper temperature for SNCR reaction becomes lower with decreasing of operation load. As the load falls off, the available O{sub 2}concentration for SNCR reactions rises gently and the initial NOx concentration for SNCR reactions debases slightly. These variations can have some influence on the SNCR process. For the upper furnace where the temperature is suitable for SNCR reactions, the CO concentration is close to 0 under different load. Consequently, the SNCR process will not be affected by CO based on the calculation in this work.

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

Energy Technology Data Exchange (ETDEWEB)

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

2010-10-15

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

Massive use of pulverized fuel ash in concrete for the construction of a U.K. power station

International Nuclear Information System (INIS)

Davies, D.R.; Kitchener, J.N.

1996-01-01

This paper describes the incorporation and benefits of pulverized fuel ash (PFA) in nearly 620,000 m 2 of concrete used in the construction of the UK's first commercial pressurized light water nuclear reactor power station, Sizewell B, Suffolk. Overall nearly 100,000 t of PFA, 1,300 t of sintered fly ash lightweight aggregate, and nearly 137,000 t of Ordinary Portland Cement (OPC) were used in the works. Generally in the construction of the main power station buildings, structural concrete with a characteristic strength of 45 N/mm 2 was placed and included fly ash as 40% of the cementitious component. Also, concrete with fly ash as 50% of the cementitious component was placed as mass fill. The program of research is reported, including sulfate resistance, heat of hydration,elastic properties, alkali-silica reaction, and long-term strength test results. Test and field results are presented and discussed. Strict quality assurance procedures were enforced and statistical summaries are offered to give an insight into the quality of control exercised. Test work and long-term results are also outlined

Aspects on prediction of two-phase reacting flow in a swirl-stabilized pulverized coal flame

Energy Technology Data Exchange (ETDEWEB)

Wennerberg, D. (LSTM, Erlangen (Germany))

1991-01-01

Knowledge of NO{sub x} formation routes in a pulverized coal flame is essential for understanding the problematics. Coal-bound N is the dominated source of NO{sub x} in a pf flame. The so-called 'thermal' NO{sub x} plays a minor role, since the temperature level is lower in a pf flame than in a gas - or oilfired flame. The coalbound N is mainly released along with the volatiles in the coal as HCN. This release takes place in the central recirculation zone when the coal is first heated up. The continued reaction processes of the HCN take different paths, dependent on whether the burner near field zone is fuel-rich or fuel-lean: Under fuel-rich conditions: HCN {yields} CN {yields} N{sub 2}. Under fuel-lean conditions: HCN {yields} NH/NCO {yields} NO. This reaction scheme is strongly simplified in order to clarify the main influence of the aerodynamics on the NO{sub x} formation. Concentration of radicals O, OH, H are also important for the reaction routes as well as the residence time for the coal particles under respective conditions. The conditions for reactions are however determined largely by the aerodynamics of the near-field burner zone. (orig./GL).

Processamento e avaliação da vida-de-prateleira do tucumã (Astrocaryum aculeatum Meyer desidratado e pulverizado Processing and shelf-life evaluation of dehydrated and pulverized tucuman (Astrocaryum aculeatum Meyer

Directory of Open Access Journals (Sweden)

Lucia Kiyoko Ozaki Yuyama

2008-06-01

Full Text Available O presente estudo teve como objetivo processar frutos de tucumã por desidratação e pulverização e avaliar sua vida-de-prateleira em diferentes tipos de embalagens e temperaturas de armazenagem. A parte comestível do fruto foi desidratada, triturada e passada em tamisador para padronização do diâmetro dos grânulos, embalada em três diferentes tipos de embalagens (plástico polietileno, laminado e lata de aço e armazenada em diferentes temperaturas (4 e 24 °C. Os frutos in natura e desidratados foram analisados quanto a umidade, pH, acidez, açúcares totais e redutores, proteínas, lipídios, cinzas, carboidratos, energia, β-caroteno e equivalente de retinol. O tucumã desidratado e pulverizado foi analisado a cada 30 dias durante 150 dias de armazenagem quanto aos índices de peróxido, de acidez e de iodo e também quanto aos parâmetros microbiológicos. Os constituintes que se destacaram, tanto no fruto in natura quanto no desidratado e pulverizado, foram: lipídios, carboidratos e, conseqüentemente, energia e β-caroteno. Em relação à vida-de-prateleira, todos os tratamentos apresentaram boa estabilidade química e microbiológica durante os 150 dias de armazenamento. Conclui-se que o tucumã desidratado e pulverizado, independente do tipo de embalagem e temperatura de armazenamento, pode ser estocado e consumido por até 150 dias, além de seu potencial nutricional como fonte de energia e β-caroteno.The present study had as objective to process tucuman by dehydration and pulverization and to evaluate its shelf-life in different types of packaging and storage temperatures. The edible part of the fruit was dehydrated, triturated and passed through a sieve to standardize granule diameter, then packed in three different types of packaging (polyethylene plastic film, laminated film, and steel can and stored at different temperatures (4 and 24 °C. The in natura and dehydrated fruits were analyzed for moisture content, p

Influence of the gray gases number in the weighted sum of gray gases model on the radiative heat exchange calculation inside pulverized coal-fired furnaces

Directory of Open Access Journals (Sweden)

Crnomarković Nenad Đ.

2016-01-01

Full Text Available The influence of the number of gray gases in the weighted sum in the gray gases model on the calculation of the radiative heat transfer is discussed in the paper. A computer code which solved the set of equations of the mathematical model describing the reactive two-phase turbulent flow with radiative heat exchange and with thermal equilibrium between phases inside the pulverized coal-fired furnace was used. Gas-phase radiative properties were determined by the simple gray gas model and two combinations of the weighted sum of the gray gases models: one gray gas plus a clear gas and two gray gases plus a clear gas. Investigation was carried out for two values of the total extinction coefficient of the dispersed phase, for the clean furnace walls and furnace walls covered by an ash layer deposit, and for three levels of the approximation accuracy of the weighting coefficients. The influence of the number of gray gases was analyzed through the relative differences of the wall fluxes, wall temperatures, medium temperatures, and heat transfer rate through all furnace walls. The investigation showed that there were conditions of the numerical investigations for which the relative differences of the variables describing the radiative heat exchange decrease with the increase in the number of gray gases. The results of this investigation show that if the weighted sum of the gray gases model is used, the complexity of the computer code and calculation time can be reduced by optimizing the number of gray gases. [Projekat Ministarstva nauke Republike Srbije, br. TR-33018: Increase in energy and ecology efficiency of processes in pulverized coal-fired furnace and optimization of utility steam boiler air preheater by using in-house developed software tools

Soil and fertilizer amendments and edge effects on the floral succession of pulverized fuel ash

Energy Technology Data Exchange (ETDEWEB)

Shaw, P. [Roehampton University, London (United Kingdom). Whitelands College

2009-01-15

Plots of fresh pulverized fuel ash (PFA, an industrial waste) were inoculated with soils from existing PFA sites and fertilizers in a factorial design, then left unmanaged for 12 years during which time the floral development and soil chemistry were monitored annually. For the first 3 years, the site supported a sparse mix of chenopods (including the scarce Chenopodium glaucum) and halophytes. As salinity declined, ruderals, legumes, and grasses plus the fire-site moss Funaria hygrometrica colonized, followed by Festuca arundinacea grassland (NVC community MG12) and Hippophae rhamnoides scrub. Dactylorhiza incarnata (orchidacea) appeared after 7 years, but only in plots that had received soil from existing orchid colonies. Four years later, a larger second generation of Dactylorhiza appeared, but only in the central zone of the site where vegetation was thinnest. By year 12, the site was dominated by coarse grasses and scrub, with early successional species persisting only in the sparsely vegetated center, where nitrate levels were lowest. This edge effect is interpreted as centripetal encroachment, a process of potentially wider concern for the conservation of low-fertility habitat patches. Overall, seed bank inoculation seems to have introduced few but desirable species (D. incarnata, Pyrola rotundifolia, some halophytes, and annuals), whereas initial application of organic fertilizer had long-lasting ({ge} 10 years) effects on cover and soil composition.

Wicking of light hydrophobic liquid phase from water by pulverized rubber: Theoretical and experimental analyses.

Science.gov (United States)

Boglaienko, Daria; Tansel, Berrin

2017-03-05

Pulverized rubber (PR) can be utilized for capturing floating oils to prevent spreading and volatilization of hydrocarbons. Experiments were conducted using PR with four different particle sizes (ranging from 0.075 to 0.600mm) and South Louisiana crude oil. The oil capture performance of the PR particles was compared with that of powdered activated carbon (AC). Oil-particle interactions were analyzed using capillary theories for lateral aggregation and wicking processes, as well as sorption capacity in relation to particle size. The sorption capacity (as oil to sorbent ratio) for PR with particle size 0.115mm (4.41g/g) was comparable to that of AC with particle size 0.187mm (5.00g/g). Sorption efficiency (oil:powder ratio, g/g) of the PR increased with decreasing particle size. Sorption of oil by PR occurred rapidly (in less than 10min) which indicated strong capillary action. No additional sorption occurred after 30min. For the PR sample with larger particle size (0.600-0.400mm), lateral aggregation was clearly noticeable. The PR-oil aggregates could be easily removed from the water surface without breaking. The cost, availability and recycling potential of PR make it a feasible alternative material for oil spill response and industrial applications which require removal of floating oils. Copyright © 2016 Elsevier B.V. All rights reserved.

Risk management of energy efficiency projects in the industry - sample plant for injecting pulverized coal into the blast furnaces

Directory of Open Access Journals (Sweden)

Jovanović Filip P.

2016-01-01

Full Text Available This paper analyses the applicability of well-known risk management methodologies in energy efficiency projects in the industry. The possibilities of application of the selected risk management methodology are demonstrated within the project of the plants for injecting pulverized coal into blast furnaces nos. 1 and 2, implemented by the company US STEEL SERBIA d.o.o. in Smederevo. The aim of the project was to increase energy efficiency through the reduction of the quantity of coke, whose production requires large amounts of energy, reduction of harmful exhaust emission and increase productivity of blast furnaces through the reduction of production costs. The project was complex and had high costs, so that it was necessary to predict risk events and plan responses to identified risks at an early stage of implementation, in the course of the project design, in order to minimise losses and implement the project in accordance with the defined time and cost limitations. [Projekat Ministarstva nauke Republike Srbije, br. 179081: Researching contemporary tendencies of strategic management using specialized management disciplines in function of competitiveness of Serbian economy

The influence of near burner region aerodynamics on the formation and emission of nitrogen oxides in a pulverized coal-fired furnace

International Nuclear Information System (INIS)

Abbas, T.; Costen, P.; Lockwood, F.C.

1992-01-01

This paper reports that detailed measurements have been performed for two distinct pulverized-coal-fired burners in a large-scale laboratory furnace. Comparative in-flame data are archived and include gas temperature, O 2 , CO concentration, and an inventory of stable fuel nitrogen species and solids (HCN, NH 3 , N 2 O, NO, nitrogen release, mass flux, and particle burnout). A significant decrease in the NO concentration in the near burner region and a substantial decrease in the furnace exit values are observed when the central tube from a single annular orifice burner jet (normally the location of a gas or oil burner for light-up purposes) is replaced with a single central orifice burner jet of same cross-sectional area. The latter burner exhibits the delayed combustion phenomena normally associated with a tangentially fired system. The particle burnout remains unaffected due to the longer particles' residence time in the all-important oxygen lean internal recirculation zone

Combustion of wet pulverized coal in reactor flow; Combustao de particulas de carvao pulverizado contendo umidade em seu interior

Energy Technology Data Exchange (ETDEWEB)

Costa, Valdeci Jose [Universidade do Planalto Catarinense (UNIPLAC), Lages, SC (Brazil). Dept. de Ciencias Exatas e Tecnologicas]. E-mail: vcosta@iscc.com.br; Krioukov, Viktor [Universidade Regional do Estado do Rio Grande do Sul (UNIJUI), Ijui, RS (Brazil). Programa de Pos-Graduacao em Modelagem Matematica]. E-mail: krioukov@main.unijui.tche.br; Maliska, Clovis Raimundo [Santa Catarina Univ., Florianopolis, SC (Brazil). Dept. de Engenharia Mecanica]. E-mail: maliska@sinmec.ufsc.br

2000-07-01

In this work I propose a numeric study destined to the combustion of wet pulverized coal in reacting flow. The mathematical model is composed by equations for the concentration of the substances in the reacting flow, written based in the chemical kinetics and exponential form, conservation equations and devolatilization equations, combustion of the carbon and residues. The study detects fluctuation among the temperatures of the gas and of the particles. The inclusion of the humidity as constituent part of the volatile matter doesn't affect the performance of the model, however, its presence alters the temperature profiles and the gaseous composition. With the increase of the humidity in the coal have a slight reduction in the time of combustion of the particle, what agrees with experimental data. The model foresees an increment in the difference Tp-Tg and a smaller production of CO with the increase of the wetness rate. The volatile ones, in spite of they have its fraction relatively reduced with the wetness presence they are liberated more slowly with its increment, provoking change in the position of front flame. (author)

Ignition and devolatilization of pulverized coals in lower oxygen content O{sub 2}/CO{sub 2} atmosphere

Energy Technology Data Exchange (ETDEWEB)

Huang, Xiaohong; Li, Jing; Liu, Zhaohui; Yang, Ming; Wang, Dingbang; Zheng, Chuguang [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion

2013-07-01

High speed camera is employed to capture the transient images of the burning particle in a flat-flame entrained flow reactor, some information of the burning particle, such as the optical intensity and the residence time, are obtained through analysis of transient images. The ignition and devolatilization behavior of different rank coals at 1,670, 1,770 and 1,940 K over a range of 2-30% O{sub 2} in both N{sub 2} and CO{sub 2} diluent gases are researched. The results indicate that the laws of ignition and devolatilization of pulverized coals in low oxygen O{sub 2}/CO{sub 2} atmosphere are consistent with the literature, which focus on the environments of high oxygen contents (10-30%) or lower temperate (900-1,500 K). With the gas temperature and oxygen content increased, the ignition delay time and devolatilization time for the lower oxygen content cases decreased for both N{sub 2} and CO{sub 2} atmosphere. With the use CO{sub 2} in place of N{sub 2} in low oxygen content, the ignition delay was retarded and the duration of devolatilization was increased. The effect of CO{sub 2} on coal particle ignition is explained by its higher molar specific heat. And the effect of CO{sub 2} on devolatilization results from its effect on the diffusion rates of volatile fuel and oxygen.

REDUCING THE INTENSITY OF TAKEAWAY PULVERIZED COAL BY USING SPECIAL SOLUTION

Directory of Open Access Journals (Sweden)

M. M. Biliaiev

2017-04-01

Full Text Available Purpose. The article is aimed: 1 to develop the coal coating solution in open railway cars or to cover coal piles to minimize the coal dust losses; 2 creating a mathematical model of the process of the solution feeding to the surface of coal. Methodology. To solve this problem, it was developed a special solution containing cheap industrial wastes and semiproducts of chemical industries. It was conducted a physical experiment to assess the intensity of coal dust loss when using the developed solution. A mathematical model based on the use of the motion equations of the ideal fluid and mass transfer was developed. The developed numerical models are the basis of the application program package created for assessing the quality of processing the coal surface by special solution. Findings. The results of the conducted physical experiment to assess the magnitude of the coal dust loss on the model of the coal pile in the processing of its surface with a special solution and without processing are presented in the article. It is shown that the application of the proposed solution for surface processing of coal can significantly reduce the coal dust loss. This makes it possible to reduce the amount of economic losses and reduce the level of air dust pollution in work areas. The results of computational experiments carried out on the basis of the constructed numerical models are presented in the article. Originality. Authors proposed a new solution for the coal surface processing in order to minimize the removal of pulverized coal from the coal pile, which substantially reduces the coal losses. There were created numerical models to take into account the relevant factors influencing the solution dispersion process in the atmosphere from coal processing in gondola cars. Practical value. Solution, proposed in the article has a low price, because it can be created on the basis of industrial production wastes. Application of this solution can significantly

Numerical study on NO formation in a pulverized coal-fired furnace using oxy-fuel combustion

Energy Technology Data Exchange (ETDEWEB)

Zhang, Aiyue; Chen, Yuan; Sheng, Changdong [Southeast Univ., Nanjing (China). School of Energy and Environment

2013-07-01

Computational fluid dynamics (CFD) approach was employed to numerically investigate NO formation in a 600 MW wall-fired pulverized coal-fired furnace retrofitted for oxy-coal combustion, aimed at the impacts of flue gas recycle ratio, O{sub 2} staging and recycled NO with the recycled flue gas (RFG) on NO formation and emission. An in-house CFD research code for conventional air combustion was developed and extended to simulate O{sub 2}/RFG combustion with specific considerations of the change of gas properties and its impact on coal particle combustion processes. The extended De Soete mechanisms including NO reburning mechanism were applied to describe transformations of fuel nitrogen. It was shown that CFD simulation represented the significant reduction of NO formation during O{sub 2}/RFG combustion compared to that during air combustion. The in-burner and particularly the in-furnace O{sub 2} staging were confirmed still to play very important roles in NO formation control. Changing the recycle ratio had significant impact on the combustion performance and consequently on NO formation and emission. With the combustion performance ensured, decreasing the flue gas recycle ratio or increasing the inlet O{sub 2} concentration of combustion gas led to reduction of NO formation and emission. Although NO formation and emission was found to increase with increasing the inlet NO concentration of combustion gas, CFD simulation indicated that {proportional_to}74% of the inlet NO was reduced in the furnace, consistent with the experimental data reported in the literature. This demonstrated the significant contribution of reburning mechanism to the reduction of the recycled NO in the furnace.

Chemical forms of the fluorine and carbon in fly ashes recovered from electrostatic precipitators of pulverized coal-fired plants

Energy Technology Data Exchange (ETDEWEB)

Naoto Tsubouchi; Hidekazu Hayashi; Akiyuki Kawashima; Masahide Sato; Noboru Suzuki; Yasuo Ohtsuka [Tohoku University, Sendai (Japan). Institute of Multidisciplinary Research for Advanced Materials

2011-01-15

The functionalities of the fluorine and carbon present in fly ashes formed in pulverized coal combustion have been studied with X-ray photoelectron spectroscopy (XPS) and temperature-programmed desorption (TPD) techniques. The ash samples include 20-130 {mu}g/g-dry and 0.4-4.1 mass%-dry of fluorine and carbon elements, respectively, and these components are enriched at the outermost layer of the ash surface. The F consists of both inorganic and organic functionalities, and the proportion of the latter is as high as 84-98 mol%. The C has different types of surface oxygen species, such as carboxyl, lactone/acid anhydride and phenolic groups, and most of these groups decompose to CO{sub 2} or CO up to 700{sup o}C to yield carbon active sites. When the amount of the O-functional forms increases, the content of organic C-F forms tends to increase almost linearly. On the basis of the above results, it may be speculated as one possibility that the formation of covalent C-F bonds takes place mainly through secondary reactions between gaseous F-containing compounds (HF and/or F{sub 2}) in flue gas and carbon active sites produced below 700{sup o}C downstream of coal-fired boilers. 30 refs., 8 figs., 4 tabs.

Transformations and affinities for sulfur of Chinese Shenmu coal ash in a pulverized coal-fired boiler

Energy Technology Data Exchange (ETDEWEB)

Cheng, J.; Zhou, J.H.; Liu, J.Z.; Cao, X.Y.; Cen, K.F. [Zhejiang University, Hangzhou (China)

2009-07-01

The self-desulfurization efficiency of Shenmu coal with a high initial Ca/S molar ratio of 2.02 was measured in a 1,025 t/h pulverized coal-fired boiler. It increases from 29% to 32% when the power capacity decreases from 100% to 70%. About 60% of the mineral matter and calcium element fed into the furnace is retained in the fly ash, while less than 10% is retained in the bottom ash. About 70% of the sulfur element fed into the furnace is emitted as SO{sub 2} in the flue gas, while less than 10% is retained in the fly ash and less than 1% is retained in the bottom ash. The mineralogical compositions of feed coal, fly ash, and bottom ash were obtained by X-ray diffraction analysis. It is found that the initial amorphous phase content is 91.17% and the initial CaCO{sub 3} phase content is 2.07% in Shenmu coal. The vitreous phase and sulfation product CaSO{sub 4} contents are, respectively, 70.47% and 3.36% in the fly ash obtained at full capacity, while the retained CaCO{sub 3} and CaO contents are, respectively, 4.73% and 2.15%. However, the vitreous phase content is only 25.68% and no CaSO{sub 4} is detected in the bottom ash obtained at full capacity. When the power capacity decreases from 100% to 70%, the vitreous phase content in fly ash decreases from 70.47% to 67.41% and that in bottom ash increases from 25.68% to 28.10%.

Combustion behaviors and kinetics of sewage sludge blended with pulverized coal: With and without catalysts.

Science.gov (United States)

Wang, Zhiqiang; Hong, Chen; Xing, Yi; Li, Yifei; Feng, Lihui; Jia, Mengmeng

2018-04-01

The combustion behaviors of sewage sludge (SS), pulverized coal (PC), and their blends were studied using a thermogravimetric analyzer. The effect of the mass ratio of SS to PC on the co-combustion characteristics was analyzed. The experiments showed that the ignition performance of the blends improved significantly as the mass percentage of SS increased, but its combustion intensity decreased. The burnout temperature (T b ) and comprehensive combustibility index (S) of the blends were almost unchanged when the mass percentage of SS was less than 10%. However, a high mass percentage of SS (>10%) resulted in a great increase in T b and a notable decrease in S. Subsequently, the effects of different catalysts (CaO, CeO 2 , MnO 2 , and Fe 2 O 3 ) on the combustion characteristics and activation energy of the SS/PC blend were investigated. The four catalysts promoted the release and combustion of volatile matters in the blended fuels and shifted their combustion profiles to a low temperature. In addition, their peak separating tendencies were obvious at 350-550 C, resulting in high peak widths. All the catalysts improved combustion activity of the blended fuel and accelerated fixed carbon combustion, which decreased the ignition temperature and burnout temperature of the fuels. CeO 2 had the best catalytic effects in terms of the comprehensive combustion performance and activation energy, followed closely by Fe 2 O 3 . However, the rare-earth compounds are expensive to be applied in the catalytic combustion process of SS/PC blend at present. Based on both catalytic effects and economy, Fe 2 O 3 was potentially an optimal option for catalytic combustion among the tested catalysts. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of Ultrafine Pulverization of Senecio Scandens on Growth, Immune System and Faecal Microorganisms in Piglets

Directory of Open Access Journals (Sweden)

J Yue1, CQ Lu1, HY Lin1, XN Wang, JQ Zheng1, JJ Chen1* and R Gooneratne2*

2016-11-01

Full Text Available There is increased interest in using naturally occurring compounds subjected to new technologies for enhancing pig nutrition to replace antibiotic usage in swine production. The effects of ultrafine pulverization on the size distribution, morphology of Senecio scandens Buch.-Ham., and the growth performance, serum immunity parameters and faecal microorganisms of piglets fed this powder were investigated. The size distribution and morphology of S. scandens were characterized by using a laser diffraction analyser and scanning electron microscopy respectively. Ninety Duroc×Landrace×Yorkshire piglets (average body weight of 10.43kg were randomly assigned to six treatments with three pens of five pigs per treatment. Group 1 (Control piglets were fed the basal diet only. Groups 2 to 5 were fed with the basal diet supplemented with ultrafine powder (median diameter [d0.5] of 8.89μm of S. scandens at 0.3, 0.6, 0.9, and 1.2% of the basal diet, respectively, for 30 days. For group 6, 1.2% of ordinary S. scandens powder (d0.5=88.59μm was added to the basal diet. Both S. scandens ordinary and ultrafine powder increased piglet body weight and reduced the feed to gain ratio, but the performance of piglets fed the ultrafine powder was better. In groups 4 to 6, the number of Escherechia coli in faeces and the diarrhoeal incidence were significantly lower (P<0.05 and the serum IgA, IgG, IgM contents significantly higher (P<0.05. Feeding S. scandens ultrafine powder in the diet improved piglet performance and the diet supplemented with 0.9% of the ultrafine powder was the most effective.

Effect of multiphase radiation on coal combustion in a pulverized coal jet flame

International Nuclear Information System (INIS)

Wu, Bifen; Roy, Somesh P.; Zhao, Xinyu; Modest, Michael F.

2017-01-01

The accurate modeling of coal combustion requires detailed radiative heat transfer models for both gaseous combustion products and solid coal particles. A multiphase Monte Carlo ray tracing (MCRT) radiation solver is developed in this work to simulate a laboratory-scale pulverized coal flame. The MCRT solver considers radiative interactions between coal particles and three major combustion products (CO 2 , H 2 O, and CO). A line-by-line spectral database for the gas phase and a size-dependent nongray correlation for the solid phase are employed to account for the nongray effects. The flame structure is significantly altered by considering nongray radiation and the lift-off height of the flame increases by approximately 35%, compared to the simulation without radiation. Radiation is also found to affect the evolution of coal particles considerably as it takes over as the dominant mode of heat transfer for medium-to-large coal particles downstream of the flame. To investigate the respective effects of spectral models for the gas and solid phases, a Planck-mean-based gray gas model and a size-independent gray particle model are applied in a frozen-field analysis of a steady-state snapshot of the flame. The gray gas approximation considerably underestimates the radiative source terms for both the gas phase and the solid phase. The gray coal approximation also leads to under-prediction of the particle emission and absorption. However, the level of under-prediction is not as significant as that resulting from the employment of the gray gas model. Finally, the effect of the spectral property of ash on radiation is also investigated and found to be insignificant for the present target flame. - Highlights: • A Monte Carlo–based nongray radiation solver is developed to study effects of radiation. • Radiation alters the lift-off height, and the distribution of temperature andspecies for the target flame. • Radiation alters the heat transfer mechanism of medium

The enrichment behavior of natural radionuclides in pulverized oil shale-fired power plants

International Nuclear Information System (INIS)

Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry

2014-01-01

The oil shale industry is the largest producer of NORM (Naturally Occurring Radioactive Material) waste in Estonia. Approximately 11–12 million tons of oil shale containing various amounts of natural radionuclides is burned annually in the Narva oil shale-fired power plants, which accounts for approximately 90% of Estonian electricity production. The radionuclide behavior characteristics change during the fuel combustion process, which redistributes the radionuclides between different ash fractions. Out of 24 operational boilers in the power plants, four use circulating fluidized bed (CFB) technology and twenty use pulverized fuel (PF) technology. Over the past decade, the PF boilers have been renovated, with the main objective to increase the efficiency of the filter systems. Between 2009 and 2012, electrostatic precipitators (ESP) in four PF energy blocks were replaced with novel integrated desulphurization technology (NID) for the efficient removal of fly ash and SO 2 from flue gases. Using gamma spectrometry, activity concentrations and enrichment factors for the 238 U ( 238 U, 226 Ra, 210 Pb) and 232 Th ( 232 Th, 228 Ra) family radionuclides as well as 40 K were measured and analyzed in different PF boiler ash fractions. The radionuclide activity concentrations in the ash samples increased from the furnace toward the back end of the flue gas duct. The highest values in different PF boiler ash fractions were in the last field of the ESP and in the NID ash, where radionuclide enrichment factors were up to 4.2 and 3.3, respectively. The acquired and analyzed data on radionuclide activity concentrations in different PF boiler ashes (operating with an ESP and a NID system) compared to CFB boiler ashes provides an indication that changes in the fuel (oil shale) composition and boiler working parameters, as well as technological enhancements in Estonian oil shale fired power plants, have had a combined effect on the distribution patterns of natural radionuclides in

A comprehensive study of combustion products generated from pulverized peat combustion in the furnace of BKZ-210-140F steam boiler

Science.gov (United States)

Kuzmin, V. A.; Zagrai, I. A.

2017-11-01

The experimental and theoretical study of combustion products has been carried out for the conditions of pulverized peat combustion in BKZ-210-140F steam boiler. Sampling has been performed in different parts of the boiler system in order to determine the chemical composition, radiative properties and dispersity of slag and ash particles. The chemical composition of particles was determined using the method of x-ray fluorescence analysis. Shapes and sizes of the particles were determined by means of electron scanning microscopy. The histograms and the particle size distribution functions were computed. The calculation of components of the gaseous phase was based on the combustion characteristics of the original fuel. The software package of calculation of thermal radiation of combustion products from peat combustion was used to simulate emission characteristics (flux densities and emissivity factors). The dependence of emission characteristics on the temperature level and on the wavelength has been defined. On the basis of the analysis of emission characteristics the authors give some recommendations how to determine the temperature of peat combustion products in the furnace of BKZ-210-140F steam boiler. The findings can be used to measure the combustion products temperature, support temperature control in peat combustion and solve the problem of boiler furnace slagging.

Fiscal 2001 achievement report. Development of coal gas production technology for fuel cells - Research using pilot test facility - for public release (Test result report - 2/3); 2001 nendo seika hokokusho (Kokai you). Nenryo denchi you sekitan gas seizo gijutsu kaihatsu - Pilot shiken setsubi ni yoru kenkyu (Shiken kekka hokokusho 2/3)

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-03-01

For the development of a coal gasification furnace optimum for fuel cells, a pilot test facility was constructed, and the results of tests and inspections conducted therefor are put together. They include an individual test of the receiving pit hopper vibrator, individual test of the pulverized coal related rotary valve, individual test of the pretreatment compressed air fan, individual test of the coal pulverizer lubricating device, individual test of the coal pulverizer pressure device, individual test of the coal pulverizer, individual test of the coal pulverizer motor, individual test of the coal feeder, individual test of the pulverized coal bunker exhaust fan, individual test of the pulverized coal bunker exhaust fan motor, test of capacity for pulverized coal, individual test of the pulverized coal conveyer blower, test of the sequence of the same, test of pulverizer inert clearing, individual test of the pretreatment condensed water pump in the coal pretreatment device, test of airborne conveyance in the same, verification test of inter-hopper transfer in the same, test of coal pulverization in the same, test operation of the raw material air/low pressure nitrogen compressor in the air separation facility, test operation of the raw material air freezer in the same, and a test operation of the MS adsorber/MS regeneration electric heater. (NEDO)

Distribution of trace elements in selected pulverized coals as a function of particle size and density

Science.gov (United States)

Senior, C.L.; Zeng, T.; Che, J.; Ames, M.R.; Sarofim, A.F.; Olmez, I.; Huggins, Frank E.; Shah, N.; Huffman, G.P.; Kolker, A.; Mroczkowski, S.; Palmer, C.; Finkelman, R.

2000-01-01

Trace elements in coal have diverse modes of occurrence that will greatly influence their behavior in many coal utilization processes. Mode of occurrence is important in determining the partitioning during coal cleaning by conventional processes, the susceptibility to oxidation upon exposure to air, as well as the changes in physical properties upon heating. In this study, three complementary methods were used to determine the concentrations and chemical states of trace elements in pulverized samples of four US coals: Pittsburgh, Illinois No. 6, Elkhorn and Hazard, and Wyodak coals. Neutron Activation Analysis (NAA) was used to measure the absolute concentration of elements in the parent coals and in the size- and density-fractionated samples. Chemical leaching and X-ray absorption fine structure (XAFS) spectroscopy were used to provide information on the form of occurrence of an element in the parent coals. The composition differences between size-segregated coal samples of different density mainly reflect the large density difference between minerals, especially pyrite, and the organic portion of the coal. The heavy density fractions are therefore enriched in pyrite and the elements associated with pyrite, as also shown by the leaching and XAFS methods. Nearly all the As is associated with pyrite in the three bituminous coals studied. The sub-bituminous coal has a very low content of pyrite and arsenic; in this coal arsenic appears to be primarily organically associated. Selenium is mainly associated with pyrite in the bituminous coal samples. In two bituminous coal samples, zinc is mostly in the form of ZnS or associated with pyrite, whereas it appears to be associated with other minerals in the other two coals. Zinc is also the only trace element studied that is significantly more concentrated in the smaller (45 to 63 ??m) coal particles.

Burning characteristics and gaseous/solid emissions of blends of pulverized coal with waste tire-derived fuel

Energy Technology Data Exchange (ETDEWEB)

Levendis, Y.A.; Atal, A.; Courtemanche, B.; Carlson, J.B. [Northeastern University, Boston, MA (United States). Dept. of Mechanical, Industrial and Manufacturing Engineering

1998-10-01

The combustion behaviour and the emissions from blends of a pulverized bituminous coal and ground waste automobile tires were investigated. Combustion took place under steady flow conditions, in an electrically-heated drop-tube furnace in air at a gas temperature of 1150{degree}C and a particle heating rate of approximate to 10{sup 5}{degree}C/s. Combustion observations were conducted with simultaneous pyrometry and cinematography. Interparticle flame interactions were visually observed in the near-stoichiometric and fuel-rich regions. Volatile flame interactions were apparent at a lower phi for tire crumb particles than for coal particles and became progressively more intense with increasing phi until at sufficiently high phi`s large group flames formed for tire particles. As particle flame interactions increased, average maximum temperatures in the flame decreased. Coal particles resisted the formation of group flames, even at high phi`s. Such observations correlated with the trends observed for the PAH emissions of the two fuels, those of tire crumb being much higher than those of coal Some stratification in the combustion of blends of particles of the two fuels was observed. This kept the PAH emissions lower levels than expected. NO{sub x} emissions from tires were much lower than those of coal, while those of the blends were close to the weighted average emissions. SO{sub 2} emissions from the blends were close to the weighted average emissions of the two fuels. Blending coal with tire reduced the CO{sub 2} emissions of coal but increased the CO emissions. Particulate emissions (soot and ash), measured in the range of 0.4 to 8{mu}m, increased with phi. Generally, tire produced more mass of submicron particulates than coal. Particulate emissions of blends of the two fuels were close to those expected based on weighted average of the two fuels.

Pilot-Scale Demonstration of ALTA for NOx Control in Pulverized Coal-Fired Boilers

Energy Technology Data Exchange (ETDEWEB)

Andrew Fry; Devin Davis; Marc Cremer; Bradley Adams

2008-04-30

This report describes computational fluid dynamics (CFD) modeling and pilot-scale testing conducted to demonstrate the ability of the Advanced Layered Technology Approach (ALTA) to reduce NO{sub x} emissions in a pulverized coal (PC) boiler. Testing specifically focused on characterizing NO{sub x} behavior with deep burner staging combined with Rich Reagent Injection (RRI). Tests were performed in a 4 MBtu/hr pilot-scale furnace at the University of Utah. Reaction Engineering International (REI) led the project team which included the University of Utah and Combustion Components Associates (CCA). Deep burner staging and RRI, combined with selective non-catalytic reduction (SNCR), make up the Advanced Layered Technology Approach (ALTA) for NO{sub x} reduction. The application of ALTA in a PC environment requires homogenization and rapid reaction of post-burner combustion gases and has not been successfully demonstrated in the past. Operation of the existing low-NO{sub x} burner and design and operation of an application specific ALTA burner was guided by CFD modeling conducted by REI. Parametric pilot-scale testing proved the chemistry of RRI in a PC environment with a NOx reduction of 79% at long residence times and high baseline NOx rate. At representative particle residence times, typical operation of the dual-register low-NO{sub x} burner provided an environment that was unsuitable for NO{sub x} reduction by RRI, showing no NOx reduction. With RRI, the ALTA burner was able to produce NO{sub x} emissions 20% lower than the low-NO{sub x} burner, 76 ppmv vs. 94 ppmv, at a burner stoichiometric ratio (BSR) of 0.7 and a normalized stoichiometric ratio (NSR) of 2.0. CFD modeling was used to investigate the application of RRI for NO{sub x} control on a 180 MW{sub e} wall-fired, PC boiler. A NO{sub x} reduction of 37% from baseline (normal operation) was predicted using ALTA burners with RRI to produce a NO{sub x} emission rate of 0.185 lb/MBtu at the horizontal nose of

Effect of secondary fuels and combustor temperature on mercury speciation in pulverized fuel co-combustion: part 1

Energy Technology Data Exchange (ETDEWEB)

Shishir P. Sable; Wiebren de Jong; Ruud Meij; Hartmut Spliethoff [Delft University Technology, Delft (Netherlands). Section Energy Technology, Department of Process and Energy

2007-08-15

The present work mainly involves bench scale studies to investigate partitioning of mercury in pulverized fuel co-combustion at 1000 and 1300{sup o}C. High volatile bituminous coal is used as a reference case and chicken manure, olive residue, and B quality (demolition) wood are used as secondary fuels with 10 and 20% thermal shares. The combustion experiments are carried out in an entrained flow reactor with a fuel input of 7-8 kWth. Elemental and total gaseous mercury concentrations in the flue gas of the reactor are measured on-line, and ash is analyzed for particulate mercury along with other elemental and surface properties. Animal waste like chicken manure behaves very differently from plant waste. The higher chlorine contents of chicken manure cause higher ionic mercury concentrations whereas even with high unburnt carbon, particulate mercury reduces with increase in the chicken manure share. This might be a problem due to coarse fuel particles, low surface area, and iron contents. B-wood and olive residue cofiring reduces the emission of total gaseous mercury and increases particulate mercury capture due to unburnt carbon formed, fine particles, and iron contents of the ash. Calcium in chicken manure does not show any effect on particulate or gaseous mercury. It is probably due to a higher calcium sulfation rate in the presence of high sulfur and chlorine contents. However, in plant waste cofiring, calcium may have reacted with chlorine to reduce ionic mercury to its elemental form. According to thermodynamic predictions, almost 50% of the total ash is melted to form slag at 1300{sup o}C in cofiring because of high calcium, iron, and potassium and hence mercury and other remaining metals are concentrated in small amounts of ash and show an increase at higher temperatures. No slag formation was predicted at 1000{sup o}C. 24 refs., 8 figs., 4 tabs.

Revised users manual, Pulverized Coal Gasification or Combustion: 2-dimensional (87-PCGC-2): Final report, Volume 2. [87-PCGC-2

Energy Technology Data Exchange (ETDEWEB)

Smith, P.J.; Smoot, L.D.; Brewster, B.S.

1987-12-01

A two-dimensional, steady-state model for describing a variety of reactive and non-reactive flows, including pulverized coal combustion and gasification, is presented. Recent code revisions and additions are described. The model, referred to as 87-PCGC-2, is applicable to cylindrical axi-symmetric systems. Turbulence is accounted for in both the fluid mechanics equations and the combustion scheme. Radiation from gases, walls, and particles is taken into account using either a flux method or discrete ordinates method. The particle phase is modeled in a Lagrangian framework, such that mean paths of particle groups are followed. Several multi-step coal devolatilization schemes are included along with a heterogeneous reaction scheme that allows for both diffusion and chemical reaction. Major gas-phase reactions are modeled assuming local instantaneous equilibrium, and thus the reaction rates are limited by the turbulent rate mixing. A NO/sub x/ finite rate chemistry submodel is included which integrates chemical kinetics and the statistics of the turbulence. The gas phase is described by elliptic partial differential equations that are solved by an iterative line-by-line technique. Under-relaxation is used to achieve numerical stability. The generalized nature of the model allows for calculation of isothermal fluid mechanicsgaseous combustion, droplet combustion, particulate combustion and various mixtures of the above, including combustion of coal-water and coal-oil slurries. Both combustion and gasification environments are permissible. User information and theory are presented, along with sample problems. 106 refs.

JV Task 106 - Feasibility of CO2 Capture Technologies for Existing North Dakota Lignite-Fired Pulverized Coal Boilers

Energy Technology Data Exchange (ETDEWEB)

Michael L. Jones; Brandon M. Pavlish; Melanie D. Jensen

2007-05-01

The goal of this project is to provide a technical review and evaluation of various carbon dioxide (CO{sub 2}) capture technologies, with a focus on the applicability to lignite-fired facilities within North Dakota. The motivation for the project came from the Lignite Energy Council's (LEC's) need to identify the feasibility of CO{sub 2} capture technologies for existing North Dakota lignite-fired, pulverized coal (pc) power plants. A literature review was completed to determine the commercially available technologies as well as to identify emerging CO{sub 2} capture technologies that are currently in the research or demonstration phase. The literature review revealed few commercially available technologies for a coal-fired power plant. CO{sub 2} separation and capture using amine scrubbing have been performed for several years in industry and could be applied to an existing pc-fired power plant. Other promising technologies do exist, but many are still in the research and demonstration phases. Oxyfuel combustion, a technology that has been used in industry for several years to increase boiler efficiency, is in the process of being tailored for CO{sub 2} separation and capture. These two technologies were chosen for evaluation for CO{sub 2} separation and capture from coal-fired power plants. Although oxyfuel combustion is still in the pilot-scale demonstration phase, it was chosen to be evaluated at LEC's request because it is one of the most promising emerging technologies. As part of the evaluation of the two chosen technologies, a conceptual design, a mass and energy balance, and an economic evaluation were completed.

Real/binary co-operative and co-evolving swarms based multivariable PID controller design of ball mill pulverizing system

International Nuclear Information System (INIS)

Menhas, Muhammad Ilyas; Fei Minrui; Wang Ling; Qian Lin

2012-01-01

Highlights: ► We extend the concept of co-operation and co-evolution in some PSO variants. ► We use developed co-operative PSOs in multivariable PID controller design/tuning. ► We find that co-operative PSOs converge faster and give high quality solutions. ► Dividing the search space among swarms improves search efficiency. ► The proposed methods allow the practitioner for heterogeneous problem formulation. - Abstract: In this paper, multivariable PID controller design based on cooperative and coevolving multiple swarms is demonstrated. A simplified multi-variable MIMO process model of a ball mill pulverizing system with steady state decoupler is considered. In order to formulate computational models of cooperative and coevolving multiple swarms three different algorithms like real coded PSO, discrete binary PSO (DBPSO) and probability based discrete binary PSO (PBPSO) are employed. Simulations are carried out on three composite functions simultaneously considering multiple objectives. The cooperative and coevolving multiple swarms based results are compared with the results obtained through single swarm based methods like real coded particle swarm optimization (PSO), discrete binary PSO (DBPSO), and probability based discrete binary PSO (PBPSO) algorithms. The cooperative and coevolving swarms based techniques outperform the real coded PSO, PBPSO, and the standard discrete binary PSO (DBPSO) algorithm in escaping from local optima. Furthermore, statistical analysis of the simulation results is performed to calculate the comparative reliability of various techniques. All of the techniques employed are suitable for controller tuning, however, the multiple cooperative and coevolving swarms based results are considerably better in terms of mean fitness, variance of fitness, and success rate in finding a feasible solution in comparison to those obtained using single swarm based methods.

Coal char combustion under a CO{sub 2}-rich atmosphere: Implications for pulverized coal injection in a blast furnace

Energy Technology Data Exchange (ETDEWEB)

Borrego, A.G.; Casal, M.D. [Instituto Nacional del Carbon, CSIC. P.O. Box 73, 33080 Oviedo (Spain); Osorio, E.; Vilela, A.C.F. [Laboratorio de Siderurgia, DEMET/PPGEM - Universidade Federal do Rio Grande do Sul. P.O. Box 15021, 91501-970 Porto Alegre (Brazil)

2008-11-15

Pulverized coal injection (PCI) is employed in blast furnace tuyeres attempting to maximize the injection rate without increasing the amount of unburned char inside the stack of the blast furnace. When coal is injected with air through the injection lance, the resolidified char will burn in an atmosphere with a progressively lower oxygen content and higher CO{sub 2} concentration. In this study an experimental approach was followed to separate the combustion process into two distinct devolatilization and combustion steps. Initially coal was injected into a drop tube furnace (DTF) operating at 1300 C in an atmosphere with a low oxygen concentration to ensure the combustion of volatiles and prevent the formation of soot. Then the char was refired into the DTF at the same temperature under two different atmospheres O{sub 2}/N{sub 2} (typical combustion) and O{sub 2}/CO{sub 2} (oxy-combustion) with the same oxygen concentration. Coal injection was also performed under a higher oxygen concentration in atmospheres typical for both combustion and oxy-combustion. The fuels tested comprised a petroleum coke and coals currently used for PCI injection ranging from high volatile to low volatile bituminous rank. Thermogravimetric analyses and microscopy techniques were used to establish the reactivity and appearance of the chars. Overall similar burnouts were achieved with N{sub 2} and CO{sub 2} for similar oxygen concentrations and therefore no loss in burnout should be expected as a result of enrichment in CO{sub 2} in the blast furnace gas. The advantage of increasing the amount of oxygen in a reacting atmosphere during burnout was found to be greater, the higher the rank of the coal. (author)

Electrophysical properties of CdS layers obtained by pulverization method and annealed in hydrogen ambience; Proprietati electrofizice ale straturilor de CdS obtinute prin metoda pulverizarii cu tratare termica in hidrogen

Energy Technology Data Exchange (ETDEWEB)

Botnariuc, Vasile; Gorceac, Leonid; Coval, Andrei; Cinic, Boris; Chetrus, Petru; Raevschi, Semion; Banu, Semion [Univ. de Stat din Moldova, Chisinau (Moldova, Republic of)

2012-07-15

CdS layers were grown from the aqueous solution of CdCl{sub 2}/(NH{sub 2}){sub 2} CS having a molarity of 0,1 M by pulverization method in the temperature range of (250-450) degrees Celsius. The layers were heat treated in a hydrogen flow during 20 min at the temperatures of 350 degrees Celsius and 450 degrees Celsius. Electro- physical properties and photoluminescence of these layers were studied. For the layers deposited at 450 degrees Celsius a slight decrease of charge carriers concentration is observed with the increase of treatment temperature up to 450 degrees Celsius. The photoluminescence spectrum consists of a large band in the energy interval from 1,6 eV to 2,6 eV. A photoluminescence peak with the energy of 1,95 eV is observed, which is shifting with CdS layer growth temperature increase and if reaches the value of 2,5 eV for the layers grown at the temperature of 450 degrees Celsius. (authors)

Dispersion of pollutants, environmental externalities due to a pulverized coal power plant and their effect on the cost of electricity

International Nuclear Information System (INIS)

Czarnowska, Lucyna; Frangopoulos, Christos A.

2012-01-01

Energy conversion systems generate pollution that causes damages to the environment and the society. The objective of this work is to study the dispersion of pollutants and assess the environmental and social cost due to pollution from such a system. For this purpose, a pulverized coal power plant is selected. Using thermodynamic principles combined with empirical techniques, the quantities of pollutants emitted by the plant are estimated. Then, using the EcoSenseWeb software, which is based on the results of the ExternE project, the external environmental cost (externalities) of pollution is assessed. The plant is considered as located in four different cities in Poland and the externalities are calculated for each city separately. It is shown that the external environmental cost has a strong influence on the unit cost of electricity. In addition, the dispersion of pollutants is presented for the plant located in Olsztyn city. Furthermore, the plant is considered as located near the capitals of European countries and the environmental externalities are calculated for each city. The neighboring countries that are strongly affected by the plant in each particular city are identified. The sensitivity of the unit cost of electricity to certain important parameters is investigated. -- Highlights: ► The external cost of pollution has a significant impact on the cost of electricity. ► The results depend on the particular plant, location and level (local-global). ► Externalities make the installation of abatement equipment economical. ► The source location of emissions has a significant effect on the external cost. ► The transboundary pollution has a strong effect on the environmental cost.

Simplified process for leaching precious metals from fuel cell membrane electrode assemblies

Science.gov (United States)

Shore, Lawrence [Edison, NJ; Matlin, Ramail [Berkeley Heights, NJ

2009-12-22

The membrane electrode assemblies of fuel cells are recycled to recover the catalyst precious metals from the assemblies. The assemblies are cryogenically embrittled and pulverized to form a powder. The pulverized assemblies are then mixed with a surfactant to form a paste which is contacted with an acid solution to leach precious metals from the pulverized membranes.

In situ transmission electron microscopy observation of pulverization of aluminum nanowires and evolution of the thin surface Al2O3 layers during lithiation-delithiation cycles.

Science.gov (United States)

Liu, Yang; Hudak, Nicholas S; Huber, Dale L; Limmer, Steven J; Sullivan, John P; Huang, Jian Yu

2011-10-12

Lithiation-delithiation cycles of individual aluminum nanowires (NWs) with naturally oxidized Al(2)O(3) surface layers (thickness 4-5 nm) were conducted in situ in a transmission electron microscope. Surprisingly, the lithiation was always initiated from the surface Al(2)O(3) layer, forming a stable Li-Al-O glass tube with a thickness of about 6-10 nm wrapping around the NW core. After lithiation of the surface Al(2)O(3) layer, lithiation of the inner Al core took place, which converted the single crystal Al to a polycrystalline LiAl alloy, with a volume expansion of about 100%. The Li-Al-O glass tube survived the 100% volume expansion, by enlarging through elastic and plastic deformation, acting as a solid electrolyte with exceptional mechanical robustness and ion conduction. Voids were formed in the Al NWs during the initial delithiation step and grew continuously with each subsequent delithiation, leading to pulverization of the Al NWs to isolated nanoparticles confined inside the Li-Al-O tube. There was a corresponding loss of capacity with each delithiation step when arrays of NWs were galvonostatically cycled. The results provide important insight into the degradation mechanism of lithium-alloy electrodes and into recent reports about the performance improvement of lithium ion batteries by atomic layer deposition of Al(2)O(3) onto the active materials or electrodes.

Development and numerical/experimental characterization of a lab-scale flat flame reactor allowing the analysis of pulverized solid fuel devolatilization and oxidation at high heating rates

Energy Technology Data Exchange (ETDEWEB)

Lemaire, R., E-mail: romain.lemaire@mines-douai.fr; Menanteau, S. [Mines Douai, EI, F-59508 Douai (France)

2016-01-15

This paper deals with the thorough characterization of a new experimental test bench designed to study the devolatilization and oxidation of pulverized fuel particles in a wide range of operating conditions. This lab-scale facility is composed of a fuel feeding system, the functioning of which has been optimized by computational fluid dynamics. It allows delivering a constant and time-independent mass flow rate of fuel particles which are pneumatically transported to the central injector of a hybrid McKenna burner using a carrier gas stream that can be inert or oxidant depending on the targeted application. A premixed propane/air laminar flat flame stabilized on the porous part of the burner is used to generate the hot gases insuring the heating of the central coal/carrier-gas jet with a thermal gradient similar to those found in industrial combustors (>10{sup 5} K/s). In the present work, results issued from numerical simulations performed a priori to characterize the velocity and temperature fields in the reaction chamber have been analyzed and confronted with experimental measurements carried out by coupling particle image velocimetry, thermocouple and two-color pyrometry measurements so as to validate the order of magnitude of the heating rate delivered by such a new test bench. Finally, the main features of the flat flame reactor we developed have been discussed with respect to those of another laboratory-scale system designed to study coal devolatilization at a high heating rate.

Development and numerical/experimental characterization of a lab-scale flat flame reactor allowing the analysis of pulverized solid fuel devolatilization and oxidation at high heating rates.

Science.gov (United States)

Lemaire, R; Menanteau, S

2016-01-01

This paper deals with the thorough characterization of a new experimental test bench designed to study the devolatilization and oxidation of pulverized fuel particles in a wide range of operating conditions. This lab-scale facility is composed of a fuel feeding system, the functioning of which has been optimized by computational fluid dynamics. It allows delivering a constant and time-independent mass flow rate of fuel particles which are pneumatically transported to the central injector of a hybrid McKenna burner using a carrier gas stream that can be inert or oxidant depending on the targeted application. A premixed propane/air laminar flat flame stabilized on the porous part of the burner is used to generate the hot gases insuring the heating of the central coal/carrier-gas jet with a thermal gradient similar to those found in industrial combustors (>10(5) K/s). In the present work, results issued from numerical simulations performed a priori to characterize the velocity and temperature fields in the reaction chamber have been analyzed and confronted with experimental measurements carried out by coupling particle image velocimetry, thermocouple and two-color pyrometry measurements so as to validate the order of magnitude of the heating rate delivered by such a new test bench. Finally, the main features of the flat flame reactor we developed have been discussed with respect to those of another laboratory-scale system designed to study coal devolatilization at a high heating rate.

Elysia bangtawaensis Swennen (Nudibranch) from the mangrove habitat of Mandovi estuary, Goa (central west coast), India

Digital Repository Service at National Institute of Oceanography (India)

Jagtap, T.G.; Shenai-Tirodkar, P.S.; Savant, S.B.; Kulkarni, V.A.; Ansari, Z.A.

with the duration of the pulverization period. The study reveals that a good amount of tungsten and cobalt get transferred into the sample during pulverization from the tungsten-carbide cup. The con- tamination of tungsten and cobalt from the pulverizing cup... (Table 2). The popu- lation declined from mid-January 2008. The present form of Elysia was con- fined to the mid-reaches of estuarine Figure 1. Geographical positions of sampling stations. Figure 2. Elysia bangtawaensis from various...

Production of fine powder from silk by radiation

International Nuclear Information System (INIS)

Takeshita, Hidefumi; Yoshii, Fumio; Kume, Tamikazu

2000-01-01

Silk fine power was prepared directly from silk fiber irradiated with an accelerated electron beam(EB). Irradiated silk fiber was well pulverized only by physical crushing using ball mill without any chemical pretreatment. Raw and degummed silk fibers were irradiated at ambient temperature in the dose range of 250-1000 kGy. Although unirradiated silk fibers were not pulverized at all, irradiated fibers were easily pulverized and showed higher conversion from fiber to powder for higher doses. The presence of oxygen in the irradiation atmosphere enhanced pulverization of silk fiber. Raw silk fibers were less pulverized compared to degummed ones. The electron microscope observation showed that the minimum particle size of silk powder obtained from fiber irradiated by 1000 kGy in oxygen was less than 10 microns. It was found that fibroin powder obtained in this work dissolved remarkably into cold water, thought unirradiated fibroin fiber had little solubility even in hot water. A typical soluble fraction was about 60% for fibroin powder obtained from fiber irradiated by 1000 kGy in oxygen. (author)

Manufacturing method of hydrogen storage alloy powder for battery; Denchiyo suiso kyuzo gokin funmatsu no seizo hoho

Energy Technology Data Exchange (ETDEWEB)

Furukawa, J.

1997-04-04

To produce hydrogen storage alloy powder for battery, ingot of a hydrogen storage alloy is crushed to coarse grains of a suitable size with a crusher and then, finely pulverized to a certain particle size with a ball mill or some other tools. In this pulverization process, the surface of the pulverized alloy powder is oxidized and the surface activity is partially lost to cause a problem of a decrease of the characteristics of the produced hydrogen storage alloy electrode. In this invention, ingot of hydrogen storage alloy is crushed to coarse alloy grains in a non-oxidizing atmosphere followed by mechanical pulverization in a state contact with a solution of sulfites, hypophosphites, hydrogen phosphates or dihydrogen phosphates. This treatment method prevents surface oxidation of the alloy powder during the pulverization process. As a result, the initial activity of the battery is improved and an increase of the internal pressure of the battery on overcharge is suppressed. The use of an aqueous alkaline solution containing cobalt instead of the above-mentioned solution gives a similar effect. 2 tabs.

Production of fine powder from silk by radiation

Energy Technology Data Exchange (ETDEWEB)

Takeshita, Hidefumi; Yoshii, Fumio; Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Ishida, Kazunari; Kamiishi, Youichi [Textile Research Institute of Gunma, Kiryu, Gunma (Japan)

2000-03-01

Silk fine power was prepared directly from silk fiber irradiated with an accelerated electron beam(EB). Irradiated silk fiber was well pulverized only by physical crushing using ball mill without any chemical pretreatment. Raw and degummed silk fibers were irradiated at ambient temperature in the dose range of 250-1000 kGy. Although unirradiated silk fibers were not pulverized at all, irradiated fibers were easily pulverized and showed higher conversion from fiber to powder for higher doses. The presence of oxygen in the irradiation atmosphere enhanced pulverization of silk fiber. Raw silk fibers were less pulverized compared to degummed ones. The electron microscope observation showed that the minimum particle size of silk powder obtained from fiber irradiated by 1000 kGy in oxygen was less than 10 microns. It was found that fibroin powder obtained in this work dissolved remarkably into cold water, thought unirradiated fibroin fiber had little solubility even in hot water. A typical soluble fraction was about 60% for fibroin powder obtained from fiber irradiated by 1000 kGy in oxygen. (author)

Use of large pieces of printed circuit boards for bioleaching to avoid 'precipitate contamination problem' and to simplify overall metal recovery.

Science.gov (United States)

Adhapure, N N; Dhakephalkar, P K; Dhakephalkar, A P; Tembhurkar, V R; Rajgure, A V; Deshmukh, A M

2014-01-01

Very recently bioleaching has been used for removing metals from electronic waste. Most of the research has been targeted to using pulverized PCBs for bioleaching where precipitate formed during bioleaching contaminates the pulverized PCB sample and making the overall metal recovery process more complicated. In addition to that, such mixing of pulverized sample with precipitate also creates problems for the final separation of non metallic fraction of PCB sample. In the present investigation we attempted the use of large pieces of printed circuit boards instead of pulverized sample for removal of metals. Use of large pieces of PCBs for bioleaching was restricted due to the chemical coating present on PCBs, the problem has been solved by chemical treatment of PCBs prior to bioleaching. In short,•Large pieces of PCB can be used for bioleaching instead of pulverized PCB sample.•Metallic portion on PCBs can be made accessible to bacteria with prior chemical treatment of PCBs.•Complete metal removal obtained on PCB pieces of size 4 cm × 2.5 cm with the exception of solder traces. The final metal free PCBs (non metallic) can be easily recycled and in this way the overall recycling process (metallic and non metallic part) of PCBs becomes simple.

Use of large pieces of printed circuit boards for bioleaching to avoid ‘precipitate contamination problem’ and to simplify overall metal recovery

Science.gov (United States)

Adhapure, N.N.; Dhakephalkar, P.K.; Dhakephalkar, A.P.; Tembhurkar, V.R.; Rajgure, A.V.; Deshmukh, A.M.

2014-01-01

Very recently bioleaching has been used for removing metals from electronic waste. Most of the research has been targeted to using pulverized PCBs for bioleaching where precipitate formed during bioleaching contaminates the pulverized PCB sample and making the overall metal recovery process more complicated. In addition to that, such mixing of pulverized sample with precipitate also creates problems for the final separation of non metallic fraction of PCB sample. In the present investigation we attempted the use of large pieces of printed circuit boards instead of pulverized sample for removal of metals. Use of large pieces of PCBs for bioleaching was restricted due to the chemical coating present on PCBs, the problem has been solved by chemical treatment of PCBs prior to bioleaching. In short,•Large pieces of PCB can be used for bioleaching instead of pulverized PCB sample.•Metallic portion on PCBs can be made accessible to bacteria with prior chemical treatment of PCBs.•Complete metal removal obtained on PCB pieces of size 4 cm × 2.5 cm with the exception of solder traces. The final metal free PCBs (non metallic) can be easily recycled and in this way the overall recycling process (metallic and non metallic part) of PCBs becomes simple. PMID:26150951

29 CFR 1926.449 - Definitions applicable to this subpart.

Science.gov (United States)

2010-07-01

... of grain and grain products, pulverized sugar and cocoa, dried egg and milk powders, pulverized... henequen, istle, jute, hemp, tow, cocoa fiber, oakum, baled waste kapok, Spanish moss, excelsior, sawdust... manner; (b) Inspecting the run of such items of equipment and materials at factories for product...

Catalytic activity of pyrite for coal liquefaction reaction; Tennen pyrite no shokubai seino ni kansuru kento

Energy Technology Data Exchange (ETDEWEB)

Hirano, K.; Kozu, M.; Okada, T.; Kobayashi, M. [Nippon Coal Oil Co. Ltd., Tokyo (Japan)

1996-10-28

Since natural pyrite is easy to obtain and cheap as coal liquefaction catalyst, it is to be used for the 150 t/d scale NEDOL process bituminous coal liquefaction pilot plant. NEDO and NCOL have investigated the improvement of catalytic activity of pulverized natural pyrite for enhancing performance and economy of the NEDOL process. In this study, coal liquefaction tests were conducted using natural pyrite catalyst pulverized by dry-type bowl mill under nitrogen atmosphere. Mechanism of catalytic reaction of the natural pyrite was discussed from relations between properties of the catalyst and liquefaction product. The natural pyrite provided an activity to transfer gaseous hydrogen into the liquefaction product. It was considered that pulverized pyrite promotes the hydrogenation reaction of asphaltene because pulverization increases its contact rate with reactant and the amount of active points on its surface. It was inferred that catalytic activity of pyrite is affected greatly by the chemical state of Fe and S on its surface. 3 refs., 4 figs., 1 tab.

Effects of aqueous extracts of Hibiscus sabdariffa calyces and ...

African Journals Online (AJOL)

The effects of aqueous extracts of the leaves of Ocimum gratissimum and calyces of Hibiscus sabdariffa on intestinal transit were determined in experimental rats The leaves of Ocimum gratissimum were oven dried and then pulverized. The dried calyces of Hibiscus sabdariffa were also pulverized. 10% extracts of both ...

Pulverized coal devolatilization prediction

International Nuclear Information System (INIS)

Rojas, Andres F; Barraza, Juan M

2008-01-01

The aim of this study was to predict the two bituminous coals devolatilization at low rate of heating (50 Celsius degrade/min), with program FG-DVC (functional group Depolymerization. Vaporization and crosslinking), and to compare the devolatilization profiles predicted by program FG-DVC, which are obtained in the thermogravimetric analyzer. It was also study the volatile liberation at (10 4 k/s) in a drop-tube furnace. The tar, methane, carbon monoxide, and carbon dioxide, formation rate profiles, and the hydrogen, oxygen, nitrogen and sulphur, elemental distribution in the devolatilization products by FG-DVC program at low rate of heating was obtained; and the liberation volatile and R factor at high rate of heating was calculated. it was found that the program predicts the bituminous coals devolatilization at low rate heating, at high rate heating, a volatile liberation around 30% was obtained

2187-IJBCS -Article-Christiana Ogwuche

African Journals Online (AJOL)

hp

This study investigates the antimicrobial activity of the leaf of the white specie of Sesamum indicum from the region of Benue State, Nigeria. The leaf of the plant was air dried under shade, segregated and pulverized. 840.56g of the pulverized plant materials were carefully weighed and loaded into a Soxhlet extractor.

Observer-Based Fuel Control Using Oxygen Measurement. A study based on a first-principles model of a pulverized coal fired Benson Boiler

Energy Technology Data Exchange (ETDEWEB)

Andersen, Palle; Bendtsen, Jan Dimon; Mortensen, Jan Henrik; Just Nielsen, Rene; Soendergaard Pedersen, Tom [Aalborg Univ. (Denmark). Dept. of Control Engineering

2005-01-01

This report describes an attempt to improve the existing control of coal mills used at the Danish power plant Nordjyllandsvaerket Unit 3. The coal mills pulverize raw coal to a fine-grained powder, which is injected into the furnace of the power plant. In the furnace the coal is combusted, producing heat, which is used for steam production. With better control of the coal mills, the power plant can be controlled more efficiently during load changes, thus improving the overall availability and efficiency of the plant. One of the main difficulties from a control point of view is that the coal mills are not equipped with sensors that detect how much coal is injected into the furnace. During the project, a fairly detailed, non-linear differential equation model of the furnace and the steam circuit was constructed and validated against data obtained at the plant. It was observed that this model was able to capture most of the important dynamics found in the data. Based on this model, it is possible to extract linearized models in various operating points. The report discusses this approach and illustrates how the model can be linearized and reduced to a lower-order linear model that is valid in the vicinity of an operating point by removing states that have little influence on the overall response. A viable adaptive control strategy would then be to design controllers for each of these simplified linear models, i.e., the control loop that sets references to the coal mills and feedwater, and use the load as a separate input to the control. The control gains should then be scheduled according to the load. However, the variations and uncertainties in the coal mill are not addressed directly in this approach. Another control approach was taken in this project, where a Kalman filter based on measurements of air flow blown into the furnace and the oxygen concentration in the flue gas is designed to estimate the actual coal flow injected into the furnace. With this estimate

Psühholoog Pulver: uskumatu. Kurb. Õõvastav / Aleksander Pulver ; intervjueerinud Tiina Jõgeda

Index Scriptorium Estoniae

Pulver, Aleksander, 1956-

2009-01-01

Vestlus Tallinna Ülikooli psühholoogia instituudi direktori Aleksander Pulveriga pedofiilia teemal. Psühholoogi seisukohavõtud laste õiguste kaitsjana ja koolihariduse uuendajana silma paistnud Kaur Hansoni pedofiiliasüüdistuste kohta

Use for refuse of shale carbonization

Energy Technology Data Exchange (ETDEWEB)

1917-09-25

A process is disclosed for using the refuse from the carbonization of bituminous shales in the preparation of light building material, characterized in that the pulverized material is mixed wet with a light filler, formed in a mold, and burned with or without the addition of clay or with the addition of binding and preserving material, preparing the mold from the pulverized material in the cold.

Fiscal 1999 achievement report on the venture business assisting type regional consortium - Minor business creation base type. Development of environmental protection oriented technology for effectively utilizing waste paper; 1999 nendo chiiki consortium kenkyu kaihatsu jigyo seika hokokusho. Kankyo hozengata no koshi no yuko riyo gijutsu no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

The effort aims to use low grade waste paper out of various grades of waste paper, whose recovery does not make good progress, as a raw material for the development of value-added, commercially competitive products and to contribute to the enhancement of waste paper recovery. A dry pulverization method less polluting the environment and not requiring a drying process is established, and types of waste paper and optimum conditions for their pulverization are made clear. A molding system using a steam injection method capable of atmospheric pressure control is established, and this enables the molding of pulverized waste paper not only into flat boards but also into corrugated boards. It is found that water contained in the waste paper alone produces a result similar to that expected from steam injection. A partitioning board is produced from waste paper, and it is found to be near the conventional product in terms of noise absorption. Old newspaper and corrugated cardboard are pulverized and an air filter is developed, which is similar to the conventional product in terms of operating efficiency and life. Waste paper is carbonized, and then charcoal with more pores than the conventional charcoal is produced. The porous charcoal is found to be usable in vegetable beds. (NEDO)

Radiation degradation of silk

Energy Technology Data Exchange (ETDEWEB)

Ishida, Kazushige; Kamiishi, Youichi [Textile Research Institute of Gunma, Kiryu, Gunma (Japan); Takeshita, Hidefumi; Yoshii, Fumio; Kume, Tamikazu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

2001-03-01

Silk fibroin powder was prepared from irradiated silk fibroin fiber by means of only physical treatment. Silk fibroin fiber irradiated with an accelerated electron beam in the dose range of 250 - 1000 kGy was pulverized by using a ball mill. Unirradiated silk fibroin fiber was not pulverized at all. But the more irradiation was increased, the more the conversion efficiency from fiber to powder was increased. The conversion efficiency of silk fibroin fiber irradiated 1000 kGy in oxygen was 94%. Silk fibroin powder shows remarkable solubility, which dissolved 57% into water of ambient temperature. It is a very interesting phenomenon that silk fibroin which did not treat with chemicals gets solubility only being pulverized. In order to study mechanism of solubilization of silk fibroin powder, amino acid component of soluble part of silk fibroin powder was analyzed. The more irradiation dose up, the more glycine or alanine degraded, but degradation fraction reached bounds about 50%. Other amino acids were degraded only 20% even at the maximum. To consider crystal construction of silk fibroin, it is suggested that irradiation on silk fibroin fiber selectively degrades glycine and alanine in amorphous region, which makes it possible to pulverize and to dissolve silk fibroin powder. (author)

A study on a new algorithm to optimize ball mill system based on modeling and GA

International Nuclear Information System (INIS)

Wang Heng; Jia Minping; Huang Peng; Chen Zuoliang

2010-01-01

Aiming at the disadvantage of conventional optimization method for ball mill pulverizing system, a novel approach based on RBF neural network and genetic algorithm was proposed in the present paper. Firstly, the experiments and measurement for fill level based on vibration signals of mill shell was introduced. Then, main factors which affected the power consumption of ball mill pulverizing system were analyzed, and the input variables of RBF neural network were determined. RBF neural network was used to map the complex non-linear relationship between the electric consumption and process parameters and the non-linear model of power consumption was built. Finally, the model was optimized by genetic algorithm and the optimal work conditions of ball mill pulverizing system were determined. The results demonstrate that the method is reliable and practical, and can reduce the electric consumption obviously and effectively.

78 FR 7137 - National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial...

Science.gov (United States)

2013-01-31

...\\ oxygen) \\a\\ (ppm @3% of heat input) \\a\\ oxygen) \\b\\ Existing--Coal Stoker 0.040 (5.3E-05) 0.022 5.7E-06... Bed with FB 0.040 (5.3E-05) 0.022 5.7E-06 140 150 heat exchanger. Existing--Coal-Burning Pulverized... Fluidized Bed with FB Heat 0.0011 (2.3E-05) 0.022 8.0E-07 140 150 Exchanger. New--Coal-Burning Pulverized...

The swelling behavior of montmorillonite as affected by the grain size by in situ X-ray diffraction experiments

International Nuclear Information System (INIS)

Morodome, S.; Kawamura, K.; Owada, H.; Yahagi, R.; Kobayashi, I.

2012-01-01

Document available in extended abstract form only. In many existing researches, the swelling behavior and impermeability of smectitic engineered barrier materials in disposal facilities of radioactive waste was investigated. In the RWMC-project, the effect of smectite content on the mechanical and hydraulic behavior of smectitic materials is investigated and modeled to introduce into THMC analysis. However, since smectite is a natural resource, physical and chemical properties are different with places of production. In order to model the swelling behavior and impermeability of smectitic materials, not only the smectite content but also layer charge and crystal size will be the primary factors. In addition, smectite types and impurity minerals contents or soluble salts affect bentonite characteristic, as well. In this research, in order to focus on the effect of grain size of smectite, the swelling behavior of smectitic materials which are the same place of production but are different grain size were investigated. The smectitic material used in this study was Kunipia-F (Kunimine Industry Co. Ltd., Japan), which is from the Tukinuno Mine, Yamagata prefecture, Japan, and is purified montmorillonite produced by hydraulic elutriation. It is considered that the montmorillonite, Kunipia-F, has large crystal size, and for example Kunipia-F is able to make a sheet when drying weak solution. The grain size was conditioned by jet mill pulverizer. The pulverizing was conducted by making each other collide with high speed. The grain size of the intact and pulverized samples was measured by using of the laser scattering particle distribution analyzer and SEM. The swelling behavior was measured by in situ X-ray diffraction using of a sample chamber which can control the temperature and humidity precisely. The result of the laser scattering analysis denoted that the pulverized sample fined down expressly. The difference of the crystal aspect ratio of the pre- and post

Mechanical particle coating using polymethacrylate nanoparticle agglomerates for the preparation of controlled release fine particles: The relationship between coating performance and the characteristics of various polymethacrylates.

Science.gov (United States)

Kondo, Keita; Kato, Shinsuke; Niwa, Toshiyuki

2017-10-30

We aimed to understand the factors controlling mechanical particle coating using polymethacrylate. The relationship between coating performance and the characteristics of polymethacrylate powders was investigated. First, theophylline crystals were treated using a mechanical powder processor to obtain theophylline spheres (grindability of the agglomerates were attributed to differences in particle structure, resulting from consolidation between colloidal particles. High-grindability agglomerates exhibited higher pulverization as their glass transition temperature (T g ) increased and the further pulverization promoted coating. We therefore conclude that the minimization of polymethacrylate powder by pulverization is an important factor in mechanical particle coating using polymethacrylate with low deformability. Meanwhile, when product temperature during coating approaches T g of polymer, polymethacrylate was soften to show high coating performance by plastic deformation. The effective coating by this mechanism may be accomplished by adjusting the temperature in the processor to the T g . Copyright © 2017 Elsevier B.V. All rights reserved.

U3Si2 behavior in H2O environments: Part II, pressurized water with controlled redox chemistry

Science.gov (United States)

Nelson, A. T.; Migdisov, A.; Wood, E. Sooby; Grote, C. J.

2018-03-01

Recent interest in U3Si2 as an advanced light water reactor fuel has driven assessment of numerous properties, but characterization of its response to H2O environments is sparse in available literature. The behavior of U3Si2 in H2O containing atmospheres is investigated and presented in a two-part series of articles. This work examines the behavior of U3Si2 following exposure to pressurized H2O at temperatures from 300 to 350 °C. Testing was performed using two autoclave configurations and multiple redox conditions. Use of solid state buffers to attain a controlled water chemistry is also presented as a means to test actinide-bearing systems. Buffers were used to vary the hydrogen concentration between 1 and 30 parts per million H2. Testing included UN, U3Si5, and UO2. Both UN and U3Si5 were found to rapidly pulverize in less than 50 h at 300 °C. Uranium dioxide was included as a control for the autoclave system, and was found to be minimally impacted by exposure to pressurized water at the conditions tested for extended time periods. Testing of U3Si2 at 300 °C found reasonable stability through 30 days in 1-5 ppm H2. However, pulverization was observed following 35 days. The redox condition of testing strongly affected pulverization. Characterization of the resulting microstructures suggests that the mechanism responsible for pulverization under more strongly reducing conditions differs from that previously identified. Hydride formation is hypothesized to drive this transition. Testing performed at 350 °C resulted in rapid pulverization of U3Si2 in under 50 h.

Effect of coffee reduction on constituent concentration in an energy-efficient process of ultrasonic extraction

Directory of Open Access Journals (Sweden)

Wang Cheng-Chi

2015-01-01

Full Text Available Coffee is one of the popular beverage; its constituents include caffeine, oxidation resistant aromatic constituents, protein, tannin, and fat. It is indicated in literatures that a proper amount of coffee stimulates the brain and enhances memory, but excessive coffee causes negative results, such as coronary artery disease, high blood pressure, heart disease and kidney disease. This study used high-performance ultrasonic process to discuss the effect of pulverized coffee reduction on the constituent concentration. It further compared the constituent concentrations obtained in different extraction periods. The experimental results show that the coffee aroma constituents can be extracted effectively by ultrasonic process without any organic solvent, and the constituent concentration does not decrease with the addition of pulverized coffee. Therefore, the consumption of pulverized coffee can be reduced greatly by using the proposed. The time of extraction process can be shortened, so as to save energy. The most important point is to reduce the enterprises manufacturing cost and to increase the profit.

Method and apparatus for continuous sampling

International Nuclear Information System (INIS)

Marcussen, C.

1982-01-01

An apparatus and method for continuously sampling a pulverous material flow includes means for extracting a representative subflow from a pulverous material flow. A screw conveyor is provided to cause the extracted subflow to be pushed upwardly through a duct to an overflow. Means for transmitting a radiation beam transversely to the subflow in the duct, and means for sensing the transmitted beam through opposite pairs of windows in the duct are provided to measure the concentration of one or more constituents in the subflow. (author)

Soil is an important pathway of human lead exposure.

OpenAIRE

Mielke, H W; Reagan, P L

1998-01-01

This review shows the equal or greater importance of leaded gasoline-contaminated dust compared to lead-based paint to the child lead problem, and that soil lead, resulting from leaded gasoline and pulverized lead-based paint, is at least or more important than lead-based paint (intact and not pulverized) as a pathway of human lead exposure. Because lead-based paint is a high-dose source, the biologically relevant dosage is similar to lead in soil. Both lead-based paint and soil lead are asso...

Reuse of spent granular activated carbon for organic micro-pollutant removal from treated wastewater.

Science.gov (United States)

Hu, Jingyi; Shang, Ran; Heijman, Bas; Rietveld, Luuk

2015-09-01

Spent granular activated carbons (sGACs) for drinking water treatments were reused via pulverizing as low-cost adsorbents for micro-pollutant adsorption from a secondary treated wastewater effluent. The changes of physicochemical characteristics of the spent carbons in relation to the fresh carbons were determined and were correlated to the molecular properties of the respective GAC influents (i.e. a surface water and a groundwater). Pore size distribution analysis showed that the carbon pore volume decreased over a wider size range due to preloading by surface water, which contains a broader molecular weight distribution of organic matter in contrast to the groundwater. However, there was still considerable capacity available on the pulverized sGACs for atrazine adsorption in demineralized water and secondary effluent, and this was particularly the case for the groundwater spent GAC. However, as compared to the fresh counterparts, the decreased surface area and the induced surface acidic groups on the pulverized sGACs contributed both to the lower uptake and the more impeded adsorption kinetic of atrazine in the demineralized water. Nonetheless, the pulverized sGACs, especially the one preloaded by surface water, was less susceptible to adsorption competition in the secondary effluent, due to its negatively charged surface which can repulse the accessibility of the co-present organic matter. This suggests the reusability of the drinking water spent GACs for micro-pollutant adsorption in the treated wastewater. Copyright © 2015 Elsevier Ltd. All rights reserved.

Low emissivity insulating glazing materials: principle and examples; Les vitrages isolants a basse emissivite: principe et exemples

Energy Technology Data Exchange (ETDEWEB)

Prost, A. [Saint-Gobain Recherche, 93 - Aubervilliers (France)

1996-12-31

One of the stakes of flat glass industry is the limitation of thermal losses from indoor to outdoor through glass walls (K coefficient) in order to increase energy savings. Thermal insulation performances of a double glazing can be reinforced by the application of a highly reflective (low emissive) film with respect to thermal infrared radiation. The low emissive character is obtained with the use of surface-deposited materials that can be described using the Drude model: vacuum pulverization of metals, and vacuum pulverization or pyrolysis deposition of doped semi-conductor oxides. (J.S.)

Keskkonnaraha kolis taotlejate juurde / Andres Pulver

Index Scriptorium Estoniae

Pulver, Andres, 1965-

2005-01-01

Keskkonnainvesteeringute keskus (KIK) avas maakondlikud esindused, mis abistavad projektide arendajaid keskkonnaprojektide toetuste taotlemisel, projektide elluviimisel ning kontrollivad toetuste sihipärast kasutamist. Lisa: KIK

Aplikasi Ergonomic Function Deployment (Efd Pada Redesign Alat Parut Kelapa Untuk Ibu Rumah Tangga

Directory of Open Access Journals (Sweden)

Roberta Zulfhi Surya

2015-04-01

Ergonomic Function Deployment (Efd Application In Coconut Grater Redesign For HousewifeAbstract. Pulverizing (coconut grated is one of daily kitchen worksconducted by housewives. A common existing coconut grater which is available on the market is normally works using a crank system. Housewives have complaints of pain in the limbs, especially the hands, waist and back after using this grater. This study aims to improve the design of coconut grater with Ergonomic Function Deployment (EFD based system and determine the housewife musculoskeletal decline as users. Further, to examine pulverizing time difference after redesign. The study was conducted at RT. 001 RW. 005 West Tembilahan Hulu village, subdistrict Tembilahan Indragiri Hilir. The method use in this study is same design subject (treatment by subjects design with co added Colton equation. Atotal of 12 housewives were used and subjected to the calculation. A grater redesign with EFD system was obtained by creating House of Ergonomic (HOE matrices and determining the anthropometric data. Whilst musculoskeletal disorders were obtained by generating Nordic Body Map (NBMworksheets questionnaire. Moreover, pulverizing time was obtained by testing coconut graterused before and after redesign. Results of the study showed that the redesign tool based on Ergonomic Function Deployment (EFD systemwasfound to be more convenient form which five ergonomics aspects required was fulfilled: effective, convenient, safe, healthy, and efficient (ENASE. Housewife musculoskeletal complaints decreased by 0.285% or 17.39%. This study also shows that coconut pulverizing time is 5 minutes faster and increased by 30.10% after redesigning the coconut grater crank system.

Stochastic model of flow and dispersion of fine particles in a packed bed; Kakuritsu katei wo mochiita juten sonai deno funtai no ryudo to bunsan model

Energy Technology Data Exchange (ETDEWEB)

Takeda, K [Kawasaki Steel Corp., Tokyo (Japan); Lockwood, F

1996-06-01

For the calculation of pulverized coal combustion in a blast furnace blow pipe and tuyere, a model was built for the evaluation of the movement and dispersion of particles in a packed bed by use of a stochastic approach. In the stochastic particle trajectory calculation taking into consideration the impact of fluctuations in gas turbulence, interaction distance between particles and eddies and interaction time have to be determined, in addition to fluctuations in gas flow velocity (to be determined by measuring the instantaneous flow velocity in a normal distribution generated according to random numbers). The eddy life was determined using Shuen`s formula on the premise that the particle-eddy interaction occurs within the calculated life or the transit time, whichever is shorter. As for the turbulence energy {kappa}, it was determined by the {kappa}-{epsilon} model for the free space and by the {kappa}-Lm(mixing length) model for the packed bed. From the average of a multiplicity of particles in the experiment, such time average specific values as the average density and flow velocity vectors of particles in the space, and particle trajectories, were calculated, which proved to agree with values from experiments. Once in the packed bed, the pulverized coal underwent a sudden deceleration due to its interaction with particles in the packed bed, and the pulverized coal flow near the central axis was rapidly diffused in the packed bed. This model is expected to find its use in the study of pulverized coal combustion in the blast furnace. 18 refs., 12 figs., 2 tabs.

A study on the oxidation behavior of uranium

International Nuclear Information System (INIS)

Kim, Tae Kook; Kang, Kweon Ho; Kim, Kil Jeang; Kang, Il Sik; Jung, Kyung Whan

1998-03-01

When storing depleted uranium wastes, careful handling is required due to their very high oxidation rates. To determine the oxidation mechanism and oxidation rate of depleted uranium wastes, the most important factors to be considered in their treatment, an experiment was carried out by varying the heating rates of the Air-Controlled Oxidizer. The experiment, showed that depleted uranium wastes are pulverized after complete oxidation because of the density difference and then converted to UO 2 , U 3 O 7 , U 3 O 8 . The grain size of pulverized powder decrease with increased temperature. (author). 30 refs., 5 tabs., 28 figs

Hydriding of metallic thorium

International Nuclear Information System (INIS)

Miyake, Masanobu; Katsura, Masahiro; Matsuki, Yuichi; Uno, Masayoshi

1983-01-01

Powdered thorium is usually prepared through a combination of hydriding and dehydriding processes of metallic thorium in massive form, in which the hydriding process consists of two steps: the formation of ThH 2 , and the formation of Th 4 H 15 . However, little has yet been known as to on what stage of hydriding process the pulverization takes place. It is found in the present study that the formation of Th 4 H 15 by the reaction of ThH 2 with H 2 is responsible for pulverization. Temperature of 70 deg C adopted in this work for the reaction of formation Th 4 H 15 seems to be much more effective for production of powdered thorium than 200 - 300 deg C in the literature. The pressure-composition-temperature relationships for Th-H system are determined at 200, 300, 350, and 800 deg C. From these results, a tentative equilibrium phase diagram for the Th-H system is proposed, attention being focused on the two-phase region of ThH 2 and Th 4 H 15 . Pulverization process is discussed in terms of the tentative phase diagram. (author)

Cosmic bombardment V: Threat object-dispersing approaches to active planetary defense

Energy Technology Data Exchange (ETDEWEB)

Teller, E.; Wood, L. [Stanford Univ., CA (United States). Hoover Institution on War, Revolution and Peace]|[Lawrence Livermore National Lab., CA (United States); Ishikawa, M. [Stanford Univ., CA (United States). Dept. of Aeronautics and Astronautics]|[Lawrence Livermore National Lab., CA (United States); Hyde, R. [Lawrence Livermore National Lab., CA (United States)

1995-05-24

Earth-impacting comets and asteroids with diameters {approx}0.03 - 10 km pose the greatest threats to the terrestrial biosphere in terms of impact frequency-weighted impact consequences, and thus are of most concern to designers of active planetary defenses. Specific gravitational binding energies of such objects range from 10{sup -7} to 10{sup -2} J/gm, and are small compared with the specific energies of 1x10{sup 3} to 3x10{sup 3} J/gm required to vaporize objects of typical composition or the specific energies required to pulverize them, which are 10{sup -1} to 10 J/gm. All of these are small compared to the specific kinetic energy of these objects in the Earth- centered frame, which is 2x10{sup 5} to 2x10{sup 6} J/gm. The prospect naturally arises of negating all such threats by deflecting, pulverizing or vaporizing the objects. Pulverization-with-dispersal is an attractive option of reasonable defensive robustness. Examples of such equipments - which employ no explosives of any type - are given. Vaporization is the maximally robust defensive option, and may be invoked to negate threat objects not observed until little time is left until Earth-strike, and pulverization-with-dispersal has proven inadequate. Physically larger threats may be vaporized with nuclear explosives. No contemporary technical means of any kind appear capable of directly dispersing the -100 km diameter scale Charon- class cometary objects recently observed in the outer solar system, although such objects may be deflected to defensively useful extents. Means of implementing defenses of each of these types are proposed for specificity, and areas for optimization noted. Biospheric impacts of threat object debris are briefly considered, for bounding purposes. Experiments are suggested on cometary and asteroidal objects.

Influence of high-energy impact on the physical and technical characteristics of coal fuels

Science.gov (United States)

Mal'tsev, L. I.; Belogurova, T. P.; Kravchenko, I. V.

2017-08-01

Currently, in the world's large-scale coal-fired power industry, the combustion of pulverized coal is the most widely spread technology of combusting the coals. In recent years, the micropulverization technology for preparation and combustion of the coal has been developed in this field. As applied to the small-scale power industry, the method of combusting the coal in the form of a coal-water slurry has been explored for years. Fine coal powders are produced and used in the pulverized-coal gasification. Therefore, the coal preparation methods that involve high-dispersion disintegration of coals attract the greatest interest. The article deals with the problems of high-energy impact on the coal during the preparation of pulverized-coal fuels and coal-water slurries, in particular, during the milling of the coal in ball drum mills and the subsequent regrinding in disintegrators or the cavitation treatment of the coal-water slurries. The investigations were conducted using samples of anthracite and lignite from Belovskii open-pit mine (Kuznetsk Basin). It is shown that both the disintegration and the cavitation treatment are efficient methods for controlling the fuel characteristics. Both methods allow increasing the degree of dispersion of the coal. The content of the small-sized particles reground by cavitation considerably exceeds the similar figure obtained using the disintegrator. The specific surface area of the coal is increased by both cavitation and disintegration with the cavitation treatment producing a considerably greater effect. Being subjected to the cavitation treatment, most coal particles assume the form of a split characterized by the thermodynamically nonequilibrium state. Under external action, in particular, of temperature, the morphological structure of such pulverized materials changes faster and, consequently, the combustion of the treated coal should occur more efficiently. The obtained results are explained from the physical point of view.

Storage characteristics of hydrogen by titanium

International Nuclear Information System (INIS)

Lee, S. H.; Kang, H. S.; Back, S. W.; Choi, H. J.; Kim, K. R.; An, D. H.; Lee, H. S.; Jung, H. S.

2000-01-01

Hydrogen absorption experiments were performed by the sponge, strip and rod types of titanium(Ti) for investigating the absorption characteristics of hydrogen. From experimental results, Ti sponge showed the high hydrogen absorption capacity inspite of low reaction temperature(25 .deg. C), the H/M, which mean the capacity of hydrogen absorption was measured 2.0 for Ti sponge at 25 .deg. C. However, in case of strip and rod type of Ti, the hydrogen absorption capacities were very low in the experimental condition of 25 .deg. C. The pulverizing phenomena after metal hydriding reaction was observed in both Ti strip and Ti rod. However, the pulverizing phenomena was not observed in the Ti sponges because of high surface area

Maailmamajanduse konjunktuur : 2005 II poolaasta / B Pulver

Index Scriptorium Estoniae

Pulver, B

2005-01-01

Lühiülevaade maailmamajanduse konjunktuurist 2005. aasta II poolaastal on koostatud Müncheni Majandusuuringute Instituudi väljaande World Economic Survey nr 89 alusel. 2005. aasta juuli vaatlus näitas maailma majanduskliima stabiliseerumist soodsal tasemel. Tabelid: Ekspertide hinnangud juulis 2005 (max=9); Arenenud riikide majandusindikaatorid; Konjunktuuribaromeetrite kindlustunde indikaatorid Euroopa Liidu maades

Rakvere Teater ootab inimestelt munakive / Andres Pulver

Index Scriptorium Estoniae

Pulver, Andres, 1965-

2003-01-01

13. juunist 13. juulini etendab Rakvere Teater Neerutis A. Kivirähki "Kalevipoega". Sel puhul laseb teater kunstnik Simsonil (Simson von Seakyll) Neerutisse püsti panna Kalevipoja skulptuuri. Esimese kivi tõid telesaate "Subboteja" staarid, kes teevad Lääne-Virumaast erisaadet

Steam generators and fuel engineering utilizing solid, liquid, gaseous and special fuels

Energy Technology Data Exchange (ETDEWEB)

Thor, G

1983-01-01

Provided were technological specifications and details in the design of brown coal fired steam generators, produced in the German Democratic Republic. These steam generators range in their capacity between 1.6 and more than 1,000 t/h. The appropriate coal feeding systems, water supply and cleaning equipment, coal pulverizers and ash removal units are also manufactured. Various schemes show the design of a 25 to 64 t/h, a 320 t/h and an 815 t/h brown coal steam generator. Specifications are given for series of fuel pulverizers available, for the water circulation system and steam evaporators. The VEB Dampferzeugerbau Berlin also offers steam generators for saliniferous brown coal with a steam capacity up to 125 t/h, steam generators for pulverized black coal with a capacity up to 350 t/h and oil and gas fired generators up to 250 t/h. The company has experience in combustion of biomass (sugar cane waste) with oil in steam generators of more than 100 t/h capacity, and in projecting firing systems for other biofuels including rice, peanut and coconut hulls, wood and bark. Multi-biofuel firing in combination with coal for steam generation is also regarded as possible. (In English)

Improved coal grinding and fuel flow control in thermal power plants

DEFF Research Database (Denmark)

Niemczyk, Piotr; Bendtsen, Jan Dimon

2011-01-01

A novel controller for coal circulation and pulverized coal flow in a coal mill is proposed. The design is based on optimal control theory for bilinear systems with additional integral action. The states are estimated from the grinding power consumption and the amount of coal accumulated in the m......A novel controller for coal circulation and pulverized coal flow in a coal mill is proposed. The design is based on optimal control theory for bilinear systems with additional integral action. The states are estimated from the grinding power consumption and the amount of coal accumulated...... as well as when parameter uncertainties and noise are present. The proposed controller lowers the grinding power consumption while in most cases exhibiting superior performance in comparison with the PID controller....

Oxy-coal Combustion Studies

Energy Technology Data Exchange (ETDEWEB)

Wendt, J. [Univ. of Utah, Salt Lake City, UT (United States); Eddings, E. [Univ. of Utah, Salt Lake City, UT (United States); Lighty, J. [Univ. of Utah, Salt Lake City, UT (United States); Ring, T. [Univ. of Utah, Salt Lake City, UT (United States); Smith, P. [Univ. of Utah, Salt Lake City, UT (United States); Thornock, J. [Univ. of Utah, Salt Lake City, UT (United States); Y Jia, W. Morris [Univ. of Utah, Salt Lake City, UT (United States); Pedel, J. [Univ. of Utah, Salt Lake City, UT (United States); Rezeai, D. [Univ. of Utah, Salt Lake City, UT (United States); Wang, L. [Univ. of Utah, Salt Lake City, UT (United States); Zhang, J. [Univ. of Utah, Salt Lake City, UT (United States); Kelly, K. [Univ. of Utah, Salt Lake City, UT (United States)

2012-01-06

The objective of this project is to move toward the development of a predictive capability with quantified uncertainty bounds for pilot-scale, single-burner, oxy-coal operation. This validation research brings together multi-scale experimental measurements and computer simulations. The combination of simulation development and validation experiments is designed to lead to predictive tools for the performance of existing air fired pulverized coal boilers that have been retrofitted to various oxy-firing configurations. In addition, this report also describes novel research results related to oxy-combustion in circulating fluidized beds. For pulverized coal combustion configurations, particular attention is focused on the effect of oxy-firing on ignition and coal-flame stability, and on the subsequent partitioning mechanisms of the ash aerosol.

Interconnected Silicon Hollow Nanospheres for Lithium-Ion Battery Anodes with Long Cycle Life

KAUST Repository

Yao, Yan

2011-07-13

Silicon is a promising candidate for the anode material in lithium-ion batteries due to its high theoretical specific capacity. However, volume changes during cycling cause pulverization and capacity fade, and improving cycle life is a major research challenge. Here, we report a novel interconnected Si hollow nanosphere electrode that is capable of accommodating large volume changes without pulverization during cycling. We achieved the high initial discharge capacity of 2725 mAh g-1 with less than 8% capacity degradation every hundred cycles for 700 total cycles. Si hollow sphere electrodes also show a Coulombic efficiency of 99.5% in later cycles. Superior rate capability is demonstrated and attributed to fast lithium diffusion in the interconnected Si hollow structure. © 2011 American Chemical Society.

Soot, organics, and ultrafine ash from air- and oxy-fired coal combustion

Data.gov (United States)

U.S. Environmental Protection Agency — Pulverized bituminous coal was burned in a 10W externally heated entrained flow furnace under air-combustion and three oxy-combustion inlet oxygen conditions (28,...

DESIGN OF GRASS BRIQUETTE MACHINE

African Journals Online (AJOL)

user

E-mail addresses: 1 mike.ajieh@gmail.com, 2 dracigboanugo@yahoo.com, ... machine design was considered for processing biomass of grass origin. The machine operations include pulverization, compaction and extrusion of the briquettes.

yusuf et al

African Journals Online (AJOL)

Dr. K.J. Umar

study was aimed at isolation and characterization of compounds from the stem bark of Neocarya macrophylla. Pulverized plant ... on gingerbread plum fruit revealed its high nutritional .... chloride test) suggesting the presence of phenolic.

Efficiency of using direct-flow burners and nozzles in implementation of dry-bottom ash removal at the TPP-210A boiler furnace

Science.gov (United States)

Arkhipov, A. M.; Kanunnikov, A. A.; Kirichkov, V. S.; Prokhorov, V. B.; Fomenko, M. V.; Chernov, S. L.

2017-02-01

In reconstruction of operating pulverized coal-fired boilers, one of the main factors is the choice of a method for slag removal: dry bottom ash removal (DBAR) or slag-tap removal (STR). In this case, ecological and economic aspects should be taken into account, and also the early ignition of pulverized coal fuel, the reliability of operation of the furnace walls in the mode without slagging, and the stability of slag removal should be provided. In this work, issues of changeover of the pulverized coal-fired boilers of the TPP-210A type from the STR mode to the DBAR mode are considered. As of today, the main problems during the operation of these boilers are the high emissions of nitrogen oxides together with flue gases into the atmosphere and the appropriated payoffs, a small range of loads available, the necessity of stabilization of the pulverizedcoal flame sustainability by using the highly reactive fuel, large mechanical fuel underburning, etc. Results of studying aerodynamics of a furnace with DBAR obtained in the process of physical simulation are given; technical solutions and preliminary design (configuration of burners and nozzles in the boiler furnace, conceptual design of the pulverized coal burner, configuration of TPP-210A boiler with the low heat liberation of furnace cross-section and volumetric heat release) are set forth, which are associated with the optimization of aerodynamics of furnace volume, when the direct-flow burners and nozzles are used, and with organization of the efficient staged combustion of solid fuel. Two versions of possible modernization of a boiler unit are considered. Under conditions of the planned increase in the steam production capacity, the most promising measures are as follows: the DBAR implementation with reducing heat releases of the cross-section and volume of the furnace approximately by half, the installation of the direct-flow burners and nozzles with injection of recirculation gases into the active combustion

A Modified Split Hopkinson Pressure Bar Approach for Mimicking Dynamic Oscillatory Stress Fluctuations During Earthquake Rupture

Science.gov (United States)

Braunagel, M. J.; Griffith, W. A.

2017-12-01

Past experimental work has demonstrated that rock failure at high strain rates occurs by fragmentation rather than discrete fracture and is accompanied by a dramatic increase in rock strength. However, these observations are difficult to reconcile with the assertion that pulverized rocks in fault zones are the product of impulsive stresses during the passage of earthquake ruptures, as the distance from the principal slip zones of some pulverized rock is too great to exceed fragmentation transition. One potential explanation to this paradox that has been suggested is that repeated loading over the course of multiple earthquake ruptures may gradually reduce the pulverization threshold, in terms of both strain rate and strength. We propose that oscillatory loading during a single earthquake rupture may further lower these pulverization thresholds, and that traditional dynamic experimental approaches, such as the Split Hopkinson Pressure Bar (SHPB) wherein load is applied as a single, smooth, sinusoidal compressive wave, may not reflect natural loading conditions. To investigate the effects of oscillatory compressive loading expected during earthquake rupture propagation, we develop a controlled cyclic loading model on a SHPB apparatus utilizing two striker bars connected by an elastic spring. Unlike traditional SHPB experiments that utilize a gas gun to fire a projectile bar and generate a single compressive wave on impact with the incident bar, our modified striker bar assembly oscillates while moving down the gun barrel and generates two separate compressive pulses separated by a lag time. By modeling the modified assembly as a mass-spring-mass assembly accelerating due to the force of the released gas, we can predict the compression time of the spring upon impact and therefore the time delay between the generation of the first and second compressive waves. This allows us to predictably control load cycles with durations of only a few hundred microseconds. Initial

Demonstration experience with an abrasive blasting technique for decontaminating concrete pads

International Nuclear Information System (INIS)

Devgun, J.S.; Land, R.R.; Doane, R.W.

1990-01-01

A demonstration was performed for decontaminating a radioactivity contaminated concrete pad with a portable abrasive blasting system. The system utilizes a rotating blast wheel that scours the concrete surface with metal abrasive. The metal abrasive, pulverized concrete dust, and contaminants rebound into a separator chamber. The reusable metal abrasive is recycled, and the pulverized media are removed to an integral dust collection system. The exhaust is HEPA filtered to minimize release of airborne contaminants. However, the technique had limited success in reducing contamination around the cracks and seams in the concrete where the higher activity levels of contamination were detected during the radiological survey before the cleanup. The technique can be successful and cost-effective in decontaminating large areas of low contamination; however, careful characterization and planning are necessary. 3 refs., 3 figs., 1 tabs

Biomass co-firing

DEFF Research Database (Denmark)

Yin, Chungen

2013-01-01

Co-firing biomass with fossil fuels in existing power plants is an attractive option for significantly increasing renewable energy resource utilization and reducing CO2 emissions. This chapter mainly discusses three direct co-firing technologies: pulverized-fuel (PF) boilers, fluidized-bed combus......Co-firing biomass with fossil fuels in existing power plants is an attractive option for significantly increasing renewable energy resource utilization and reducing CO2 emissions. This chapter mainly discusses three direct co-firing technologies: pulverized-fuel (PF) boilers, fluidized......-bed combustion (FBC) systems, and grate-firing systems, which are employed in about 50%, 40% and 10% of all the co-firing plants, respectively. Their basic principles, process technologies, advantages, and limitations are presented, followed by a brief comparison of these technologies when applied to biomass co...

Direct saccharification of milo

Energy Technology Data Exchange (ETDEWEB)

1981-10-28

Crude or unrefined milo grain is pulverized to less than 100 mesh, suspended in water, and directly saccharified with enzymes. Thus, 10 kg of pulverized milo (100 mesh) was suspended in 20 liters water, liquified in the presence of bacterial amylase at 90/sup 0/ for 30 minutes and autoclaved for 10 minutes at 120/sup 0/, the liquifaction autoclave procedures were then repeated. The liquified preparation was saccharified in the presence of bacterial glucoamylase at 55/sup 0/ for 72 hours. The percentage saccharification of unrefined milo was 92-97%, which was comparable to that obtained with refined milo or a milo starch preparation. The saccharified milo preparation, when used as a sugar source in glutamic acid, lysine, or inosine fermentation, also showed similar efficiency to that of saccharified milo starch.

Method of processing radioactive solid wastes

International Nuclear Information System (INIS)

Ootaka, Hisashi; Aizu, Tadashi.

1980-01-01

Purpose: To improve the volume-reducing effect for the radioactive solids wastes by freezing and then pulverizing them. Method: Miscellaneous radioactive solid wastes produced from a nuclear power plant and packed in vinyl resin bags are filled in a drum can and nitrogen gas at low temperature (lower than 0 0 C) from a cylinder previously prepared by filling liquid nitrogen (at 15kg/cm 2 , -196 0 C) to freeze the radioactive solid wastes. Thereafter, a hydraulic press is inserted into the drum can to compress and pulverize the thus freezed miscellaneous radioactive solid wastes into powder. The powder thus formed does not expand even after removing the hydraulic press from the drum can, whereby the volume reduction of the radioactive solid wastes can be carried out effectively. (Horiuchi, T.)

Environ: E00717 [KEGG MEDICUS

Lifescience Database Archive (English)

Full Text Available tate, Ethyl myristate, beta-Irone, ethyl laurate Iris pallida [TAX:29817] ... Iridaceae Iris pallida pulverized rhizomes Obtained by ste...am distillation Major component: alpha-Irone [CPD:C09690] CAS: 8002-73-1

Device for dewatering of raw biomass. Anordning foer avvattning och uppluckring av raa biomassa

Energy Technology Data Exchange (ETDEWEB)

Kubat, J; Aabom, J J.V.; Klason, T C.F.; Bultzingsloewen, F von

1993-09-27

This invention concerns a device for loosening of raw biomass through roll dewatering. It is primarily applicable for comminuted and milled raw wood. The invention is of special interest for the production of pulverized wood fuel

Coal pump

Science.gov (United States)

Bonin, John H.; Meyer, John W.; Daniel, Jr., Arnold D.

1983-01-01

A device for pressurizing pulverized coal and circulating a carrier gas is disclosed. This device has utility in a coal gasification process and eliminates the need for a separate collection hopper and eliminates the separate compressor.

Inorganic Glue Enabling High Performance of Silicon Particles as Lithium Ion Battery Anode

KAUST Repository

Cui, Li-Feng; Hu, Liangbing; Wu, Hui; Choi, Jang Wook; Cui, Yi

2011-01-01

overcome the pulverization problem, however these nano-engineered silicon anodes usually involve very expensive processes and have difficulty being applied in commercial lithium ion batteries. In this study, we report a novel method using amorphous silicon

Interconnected Silicon Hollow Nanospheres for Lithium-Ion Battery Anodes with Long Cycle Life

KAUST Repository

Yao, Yan; McDowell, Matthew T.; Ryu, Ill; Wu, Hui; Liu, Nian; Hu, Liangbing; Nix, William D.; Cui, Yi

2011-01-01

Silicon is a promising candidate for the anode material in lithium-ion batteries due to its high theoretical specific capacity. However, volume changes during cycling cause pulverization and capacity fade, and improving cycle life is a major

Evaluation of iodine content of some selected fruits and vegetables ...

African Journals Online (AJOL)

user

2011-02-07

Feb 7, 2011 ... survival, reproductive failure, goiter and socio-economic stagnation ... 5 g of each dried sample was pulverized using mortar and pestle. 2 ... The iodine content was analyzed by Elmslie Caldwell's method as modified by ...

Türklased austasid hukkunud sõdureid / Andres Pulver

Index Scriptorium Estoniae

Pulver, Andres, 1965-

2008-01-01

14. novembril avati Rakveres Tõrma kalmistul mälestusmärk 1877.-1878. aasta Vene-Türgi sõjas vangi langenud ning Eesti pinnal surnud Türgi sõduritele. Kohal viibis ka Türgi kaitseminister Vecdi Gönül

Simulation of pulverized coal fired boiler: reaction chamber

Energy Technology Data Exchange (ETDEWEB)

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

2005-06-15

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

Combustion and gasification of coal and straw under pressurized conditions. Task 2: Determination of kinetic parameters in PTGA

Energy Technology Data Exchange (ETDEWEB)

Rathmann, O; Hald, P; Bak, J; Boll Illerup, J; Gjernes, E; Fjellerup, J; Olsen, A

1995-10-01

The reactivities of pulverized coal and straw fuels were investigated regarding pyrolysis, combustion and gasification with CO{sub 2} and H{sub 2}O by thermogravimetric analysis under pressurized conditions. The fuels were a Colombian coal, pulverized to 45-90 {mu}m particles, and wheat straw pulverized to 0-200 {mu}m particles. The pyrolysis studies were performed at 150-1000 deg. C in pure N{sub 2} at 1.5 to 40 bar. The combustion studies were performed at 300-550 deg. C, 1.5-40 bar total pressure with 0.08-0.8 bar of O{sub 2} partial pressure. The CO{sub 2} gasification studies were performed at 850-1200 deg. C, 4-40 bar of total pressure with 0.7-4 bar of CO{sub 2} partial pressure, also including studies with CO in combination with CO{sub 2}. A minor H{sub 2}O gasification study with straw was performed at 900-1050 deg. C at 1.5-2.0 bar of total pressure in an atmosphere containing partial pressures up to 0.32 bar of H{sub 2}O, o.2 bar of CO{sub 2}, 0.28 bar of CO and 0.12 bar of H{sub 2}. For combustion and CO{sub 2} gasification the results were analyzed with regard to reaction kinetics, and kinetic parameters that represent the experimental results were found. (AU) 11 tabs., 26 ills., 10 refs.

Evaluation of dense-phase ultrafine coal (DUC) as a fuel alternative for oil- and gas-designed boilers and heaters. Final report

Energy Technology Data Exchange (ETDEWEB)

1986-12-01

Utility and industrial firms currently using oil- and gas-fired boilers have an interest in substitution of coal for oil and gas as the primary boiler fuel. This interest stems from coal`s two main advantages over oil and gas-lower cost and security of supply. Recent efforts in the area of coal conversion have been directed to converting oil- and gas- fired boilers which were originally designed for coal-firing or were designed with some coal-firing capability. Boilers designed exclusively for oil- or gas-firing have not been considered viable candidates for coal conversion because they generally require a significant capacity derating and extensive and costly modifications. As a result, conversion of boilers in this class to coal-firing has generally been considered unattractive. Renewed interest in the prospects for converting boilers designed exclusively for oil- and gas-firing to coal firing has centered around the concept of using ``ultra fine`` coal as opposed to ``conventional grind`` pulverized coal. The main distinction being the finer particle size to which the former is ground. This fuel type may have characteristics which ameliorate many of the boiler problems normally associated with pulverized coal-firing. The overall concept for ultrafine coal utilization is based on a regional large preparation plant with distribution of a ready to fire fuel directly to many small users. This differs from normal practice in which final coal sizing is performed in pulverizers at the user`s site.

Co-combustion: A summary of technology

Directory of Open Access Journals (Sweden)

Leckner Bo

2007-01-01

Full Text Available Co-combustion of biomass or waste together with a base fuel in a boiler is a simple and economically suitable way to replace fossil fuels by biomass and to utilize waste. Co-combustion in a high-efficiency power station means utilization of biomass and waste with a higher thermal efficiency than what otherwise had been possible. Due to transport limitations, the additional fuel will only supply a minor part (less than a few hundreds MW fuel of the energy in a plant. There are several options: co-combustion with coal in pulverized or fluidized bed boilers, combustion on added grates inserted in pulverized coal boilers, combustors for added fuel coupled in parallel to the steam circuit of a power plant, external gas producers delivering its gas to replace an oil, gas or pulverized fuel burner. Furthermore biomass can be used for reburning in order to reduce NO emissions or for afterburning to reduce N2O emissions in fluidized bed boilers. Combination of fuels can give rise to positive or negative synergy effects, of which the best known are the interactions between S, Cl, K, Al, and Si that may give rise to or prevent deposits on tubes or on catalyst surfaces, or that may have an influence on the formation of dioxins. With better knowledge of these effects the positive ones can be utilized and the negative ones can be avoided.

Origin of planetary primordial rare gas - The possible role of adsorption.

Science.gov (United States)

Fanale, F. P.; Cannon, W. A.

1972-01-01

The degree of physical adsorption of Ne, Ar, Kr, and Xe on pulverized samples of the Allende meteorite at 113 K has been measured. The observed pattern of equilibrium enrichment of heavy rare gases over light on the pulverized meteorite surfaces relative to the gas phase is similar to the enrichment pattern exhibited by planetary primordial rare gas when compared with the composition of solar rare gas. Results indicate that, at 113 K, a total nebular pressure of from .01 to .001 atm would be required to explain the Ar, Kr, and Xe abundances in carbonaceous chondrites with an adsorption mechanism. This pressure estimate is compatible with the range of possible nebular pressures suggested by astrophysical arguments. However, the subsequent mechanism by which initially adsorbed gas might have been transferred into the interiors of grains cannot be identified at present.

Exergetic analysis of a steam power plant using coal and rice straw in a co-firing process

Energy Technology Data Exchange (ETDEWEB)

Restrepo, Alvaro; Miyake, Raphael Guardini; Bazzo, Edson [Federal University of Santa Catarina (UFSC), Dept. of Mechanical Engineering, Florianopolis, SC (Brazil)], e-mails: arestrep@labcet.ufsc.br, miyake@labcet.ufsc.br, ebazzo@emc.ufsc.br; Bzuneck, Marcelo [Tractebel Energia S.A., Capivari de Baixo, SC (Brazil). U.O. Usina Termeletrica Jorge Lacerda C.], e-mail: marcelob@tractebelenergia.com.br

2010-07-01

This paper presents an exergetic analysis concerning an existing 50 M We steam power plant, which operates with pulverized coal from Santa Catarina- Brazil. In this power plant, a co-firing rice straw is proposed, replacing up to 10% of the pulverized coal in energy basis required for the boiler. Rice straw has been widely regarded as an important source for bio-ethanol, animal feedstock and organic chemicals. The use of rice straw as energy source for electricity generation in a co-firing process with low rank coal represents a new application as well as a new challenge to overcome. Considering both scenarios, the change in the second law efficiency, exergy destruction, influence of the auxiliary equipment and the greenhouse gases emissions such as CO{sub 2} and SO{sub 2} were considered for analysis. (author)

Effect of large aspect ratio of biomass particles on carbon burnout in a utility boiler

Energy Technology Data Exchange (ETDEWEB)

D. Gera; M.P. Mathur; M.C. Freeman; Allen Robinson [Fluent, Inc./NETL, Morgantown, WV (United States)

2002-12-01

This paper reports on the development and validation of comprehensive combustion sub models that include the effect of large aspect ratio of biomass (switchgrass) particles on carbon burnout and temperature distribution inside the particles. Temperature and carbon burnout data are compared from two different models that are formulated by assuming (i) the particles are cylindrical and conduct heat internally, and (ii) the particles are spherical without internal heat conduction, i.e., no temperature gradient exists inside the particle. It was inferred that the latter model significantly underpredicted the temperature of the particle and, consequently, the burnout. Additionally, some results from cofiring biomass (10% heat input) with pulverized coal (90% heat input) are compared with the pulverized coal (100% heat input) simulations and coal experiments in a tangentially fired 150 MW{sub e} utility boiler. 26 refs., 7 figs., 4 tabs.

Update of progress for Phase II of B&W`s advanced coal-fired low-emission boiler system

Energy Technology Data Exchange (ETDEWEB)

McDonald, D.K. [Babcock & Wilcox, Barberton, OH (United States); Madden, D.A.; Rodgers, L.W. [Babcock & Wilcox, Alliance, OH (United States)] [and others

1995-11-01

Over the past five years, advances in emission control techniques at reduced costs and auxiliary power requirements coupled with significant improvements in steam turbine and cycle design have significantly altered the governing criteria by which advanced technologies have been compared. With these advances, it is clear that pulverized coal technology will continue to be competitive in both cost and performance with other advanced technologies such as Integrated Gasification Combined Cycle (IGCC) or first generation Pressurized Fluidized Bed Combustion (PFBC) technologies for at least the next decade. In the early 1990`s it appeared that if IGCC and PFBC could achieve costs comparable to conventional pulverized coal plants, their significantly reduced NO{sub x} and SO{sub 2} emissions would make them more attractive. A comparison of current emission control capabilities shows that all three technologies can already achieve similarly low emissions levels.

Observer-based Coal Mill Control using Oxygen Measurements

DEFF Research Database (Denmark)

Andersen, Palle; Bendtsen, Jan Dimon; S., Tom

2006-01-01

This paper proposes a novel approach to coal flow estimation in pulverized coal mills, which utilizes measurements of oxygen content in the flue gas. Pulverized coal mills are typically not equipped with sensors that detect the amount of coal injected into the furnace. This makes control...... of the coal flow difficult, causing stability problems and limits the plant's load following capabilities. To alleviate this problem without having to rely on expensive flow measurement equipment, a novel observer-based approach is investigated. A Kalman filter based on measurements of combustion air flow led...... into the furnace and oxygen concentration in the flue gas is designed to estimate the actual coal flow injected into the furnace. With this estimate, it becomes possible to close an inner loop around the coal mill itself, thus giving a better disturbance rejection capability. The approach is validated against...

49 The Geology and Mineralogy of Clay Occurrences Around Kutigi ...

African Journals Online (AJOL)

`123456789jkl''''#

The above results and an earlier geochemical analysis suggest that it can be utilized in .... His chemical analysis show the high dominance of SiO2 ... mortar and pestle, the sample was pulverized .... Economic Evaluation of the Kaolin Deposits.

29 CFR 1910.6 - Incorporation by reference.

Science.gov (United States)

2010-07-01

... Test for Distillation of Petroleum Products, IBR approved for §§ 1910.106(a)(5) and 1910.119(b... of Pulverized Sugar and Cocoa, IBR approved for § 1910.263(k)(2)(i). (15) NFPA 68-1954 Guide for...

Evaluation of Beilschmiedia Seed Gum as a Tablet Binder MN FEMI

African Journals Online (AJOL)

Darmstadt, Germany). The tablet disintegration rates were determined using an Apex ... seeds were sun dried, crushed using a mortar and pestle and pulverized in a blender (Model 857,. Chrome white, Osterizer, U.S.A.) to produce the gum powder.

Anomalous Shape Changes of Silicon Nanopillars by Electrochemical Lithiation

KAUST Repository

Lee, Seok Woo; McDowell, Matthew T.; Choi, Jang Wook; Cui, Yi

2011-01-01

Silicon is one of the most attractive anode materials for use in Li-ion batteries due to its ∼10 times higher specific capacity than existing graphite anodes. However, up to 400% volume expansion during reaction with Li causes particle pulverization

973-IJBCS-article-Dr Okorie Edmund

African Journals Online (AJOL)

Pr GATSING

ABSTRACT. The analysis of soils from a cement mine site and the surrounding farmland for Ni, Pb, Co and Cd at ... stabilized waste (Cho et al., 2005). ... stabilize some of these heavy metals in ... The pulverized samples were stored in plastic.

Improving the performance of si-based li-ion battery anodes by utilizing phosphorene encapsulation

NARCIS (Netherlands)

Peng, B.; Xu, Y.; Mulder, F.M.

2017-01-01

Si-based anode materials in Li-ion batteries (LIBs) suffer from severe volume expansion/contraction during repetitive discharge/charge, which results in the pulverization of active materials, continuous growth of solid electrolyte interface (SE!) layers, loss of electrical conduction, and,

Aspects chimiques de la combustion du charbon pulvérisé. Première partie Chemical Aspects of the Combustion of Pulverized Coal. Part One

Directory of Open Access Journals (Sweden)

De Soete G. G.

2006-11-01

deux mécanismes totalement différents, par exemple entre le mécanisme d'ignition homogène et le mécanisme d'ignition hétérogène du charbon, avec des conséquences pratiques pour la stabilisation de la flamme industrielle ; autre exemple : la compétition entre les divers mécanismes homogènes de formation d'oxydes d'azote et les mécanismes hétérogènes de leur réduction sur des particules solides de coke, de suie et de cendre. Avec ces idées présentes comme un leitmotiv implicite, on passe en revue les grandes étapes de la flamme industrielle de charbon pulvérisé : la dévolatilisation rapide avec la formation progressive de volatils gazeux, de goudrons et de coke ; la transformation partielle des produits gazeux et liquides de pyrolyse en suies ainsi que leur oxydation en phase gazeuse ; la combustion hétérogène du coke ; l'ignition du charbon et sa dépendance par rapport à des processus critiques homogènes et (ou hétérogènes. Comme exemple typique d'un épiphénomènechimique, on suit la transformation des espèces azotées en NO et en N2, qui se greffe en contrepoint et à chaque pas sur tes différents thèmes successifs de cette symphonie de l'oxydation du charbon. En de nombreux points de cette évolution du charbon à travers la flamme, les connaissances de la chimie de com-bustion en phase gazeuse constituent un instrument utile d'interprétation (par exemple : pour l'oxydation des volatils, pour la discussion des modalités d'ignition. II n'en reste pas moins vrai que la plupart des problèmes chimiques hétérogènes sont bien spécifiques de la flamme de charbon ; leur traitement est rendu ardu à cause de la complexité, évolutive au cours de la combustion, du combustible solide lui-même. It is not easy to obtain a full picture of the multiple chemical phenomena which occur inside a pulverized coal flame. This bibliographie review attempts to give more than just a juxtaposition of data from the recent literature and risks making

Combustion Characterization of Individual Bio-oil Droplets

DEFF Research Database (Denmark)

Hansen, Brian Brun; Jensen, Peter Arendt

2015-01-01

Single droplet combustion characteristics has been investigated for bio-oil slurries, containing biomass residue, and compared to conventional fuels for pulverized burners, such as fuel oil (start up) and wood chips (solid biomass fuel). The investigated fuels ignition delays and pyrolysis behavior...

Quality control of analyses of mercury in hair

International Nuclear Information System (INIS)

Lind, B.; Friberg, L.; Bigras, L.; Kirkbride, J.; Kennedy, P.; Kjellstroem, T.

1988-01-01

A quality control programme for mercury determinations in hair was developed within a study of 'Mental effects of prenatal methylmercury exposure in New Zealand children'. Hair was obtained from seven females with a mercury concentration of about 0.5-4 μg Hg/g. The hair was cut into 1-5 cm pieces and pulverized by liquid nitrogen grinding using a ring mill. In order to obtain a series of QC samples with varying Hg concentrations, different amounts of powder from all the samples and a reference sample of pulverized hair (11.2 μg Hg/g) were mixed. The mercury concentrations in the original samples and the mixtures were determined by radiochemical neutron activation analysis (RNAA). In total four laboratories participated in the interlaboratory comparison. All laboratories used the cold vapor AAS technique and Hg monitor model 1235, LDC for determinations after wet digestion of the samples. (orig./RB)

The behavior of ash species in suspension fired biomass boilers

DEFF Research Database (Denmark)

Jensen, Peter Arendt

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

Characteristics of Airborne Particulates Containing Naturally Occurring Radioactive Materials in Monazite Industry

Energy Technology Data Exchange (ETDEWEB)

Kim, Yong Geon; Choi, Cheol Kyu; Park, Il; Kim, Min Jun; Go, A Ra; Ji, Seung Woo; Kim, Kwang Pyo [Kyunghee University, Yongin (Korea, Republic of); Koo, Bon Cheol [KINS, Daejeon (Korea, Republic of)

2016-05-15

The objective of this study was to characterize physicochemical properties of airborne particulates at a monazite pulverization industry. The properties included particulate size distribution, concentration, shape, density, and radioactivity concentration. Monazite is one of the minerals containing naturally occurring radioactive material (NORM). Therefore, external and internal exposure can be occurred to the workers in monazite industry. The major exposure pathway of the workers is internal exposure due to inhalation of airborne particulates. According to International Commission on Radiological Protection (ICRP), radiation dose due to inhaled particulates containing NORM depends on particulate properties. Therefore, ICRP recommended the internal dose assessment using measured physicochemical properties of the airborne particulates. In the absence of specific information, ICRP provided default reference values. In this study, we characterized physicochemical properties of airborne particulates at a monazite pulverization industry. The databases of particulate information can be used for accurate internal dose assessment of worker.

Viscosity of ashes from energy production and municipal solid waste handling: A comparative study between two different experimental setups

DEFF Research Database (Denmark)

Arvelakis, Stelios; Frandsen, Flemming; Folkedahl, B.

2008-01-01

This paper discusses the viscosity characteristics of ash fractions produced from the co-combustion of coal and biomass in a pilot-scale pulverized fuel (PF) boiler and from the incineration of municipal solid waste (MSW) in a Danish incinerator that were determined using the high...

Isolation and quantification of volatiles in fish by dynamic headspace sampling and mass spectrometry

DEFF Research Database (Denmark)

Refsgaard, Hanne; Haahr, Anne-Mette; Jensen, Benny

1999-01-01

A dynamic headspace sampling method for isolation of volatiles in fish has been developed. The sample preparation involved freezing of fish tissue in liquid nitrogen, pulverizing the tissue, and sampling of volatiles from an aqueous slurry of the fish powder. Similar volatile patterns were...

NITROUS OXIDE EMISSIONS FROM FOSSIL FUEL COMBUSTION

Science.gov (United States)

The role of coal combustion as a significant global source of nitrous oxide (N2O) emissions was reexamined through on-line emission measurements from six pulverized-coal-fired utility boilers and from laboratory and pilot-scale combustors. The full-scale utility boilers yielded d...

Synthesis of Fire-Extinguishing Dawsonites

Science.gov (United States)

Altman, R. L.

1982-01-01

Simple nonaqueous process synthesizes sodium or potassium, dawsonites effective against hydrocarbon fuel fires. Fire-extinguishing alkali metal dawsonites are prepared using a finely-pulverized equimolar mixture of hydrogen carbonate, or carbonates and aluminum hydroxide heated for 1 to 6 hours under carbon dioxide pressure.

Ash Deposition Trials at Three Power Stations in Denmark

DEFF Research Database (Denmark)

Laursen, Karin; Frandsen, Flemming; Larsen, Ole Hede

1998-01-01

Six full-scale trials were conducted at three power stations in Denmark: Ensted, Funen, and Vendsyssel power stations. During these trials, pulverized coal, bottom ash, fly ash, and deposits from cooled probes were sampled and analyzed with various techniques. On the basis of SEM analyses...

Some studies on the reaction between fly ash and lime

Indian Academy of Sciences (India)

Unknown

Blain's air permeability apparatus was used for ... Pulverized lime with high per- centage of CaO (> 80 ... kept in a low-pressure autoclave at an average steam pressure and ... ing the solubility of lime in a solvent containing 1 part by volume of ...

Improved di-electric composition

Energy Technology Data Exchange (ETDEWEB)

Sharp, R C

1915-03-29

An improved di-electric composition is disclosed composed of pitch or bitumen which is melted, and to which is added, while molten, a quantity of finely ground or pulverized spent shale, the whole being mixed or stirred to make a homogeneous composition, substantially as described.

Ignition et oxydation des particules de combustible solide pulvérisé Ignition and Oxidation of Pulverized Solid Fuel

Directory of Open Access Journals (Sweden)

De Soete G. G.

2006-11-01

élais d'ignition ont été déterminés pour un grand nombre de combustibles solides de rang inférieur et supérieur (charbons, cokes, asphaltènes, suies, bois, graphite. L'étude de la vitesse expérimentale de la combustion hétérogène, notamment l'étude de la température apparente d'activation, et sa dépendance par rapport à la taille des particules et à la concentration d'oxygène, montre que, dans les conditions des essais, cette combustion est contrôlée par la désorption du CO et se déroule principalement en régime cinético-diffusionnel mixte. L'étude de la dépendance des délais d'ignition par rapport à la température, la taille des particules et la pression partielle d'oxygène, suggère que, pendant ces délais, les réactions se déroulent en régime cinétique pur et que le produit des réactions de désorption est principalement le CO. The heated-grid method is used to investigate the competition between (1 the devolatilization and subsequent oxidation of pyrolysis products and (2 the ignition of the solid matrix and its rapid combustion. A comparison between the instant of ignition and the start of pyrolysis is used to determine the range in which ignition of a pyrolyzable solid fuel of the whole coal ignitiontype (i. e. when ignition occurs before pyrolysis becomes measurable occurs as a function of temperature, particle size and oxygen concentration. The results suggest that this type of ignition might occur, as a general rule, under conditions involving pulverized solid fuels in industrial flames. In the case of whole coalignition, the rate of combustion of the solid matrix is inhibited during the period following ignition. This inhibition is due partly to the difficulty oxygen has of spreading through the pores during the discharge of pyrolysis products and partly to preferential oxygen consumption during the oxidation of pyrolysis products, mainly when this oxidation develops in the form of flames. t is only when pyrolysis ends that

Hot pressing effect on (Bi0⋅25Sb0⋅75)2Te3 mechanical and ...

Indian Academy of Sciences (India)

Administrator

Abstract. (Bi0⋅25Sb0⋅75)2Te3 thermoelectric material is a well known p type of compound that has higher fig- ... The crystal of this compound was prepared, pulverized in a particle .... ing fracture surfaces of the materials as shown in figures.

Phytochemical, antimicrobial and antiplasmodial investigations of Terminalia brownii

Science.gov (United States)

The stem bark of Terminalia brownii was collected from Machakos county, Kenya, in November 2011, and identified at the University Herbarium, School of Biological Sciences, University of Nairobi, where a voucher specimen (JM2011/502) was deposited. The stem bark was air dried in shade and pulverized....

Phytochemical constituents and antioxidant activities of aqueous ...

African Journals Online (AJOL)

USER

2010-08-02

Aug 2, 2010 ... of aqueous and methanol stem extracts of Costus afer. Ker Gawl. ... 150 g of pulverized dried sample was soaked in 600 ml distilled water and ... 0.5 g of the extract was dissolved in 2 ml glacial acetic acid containing 1 drop of ...

Development of I and C system for the coal feeder of coal firing plant

Energy Technology Data Exchange (ETDEWEB)

Kim, Teak Soo; Park, Chan Ho [Korea Electric Power Corp. (KEPCO), Taejon (Korea, Republic of). Research Center

1996-12-31

KECC(Kepco Coal Feeder Control System) receives coal weight, conveyor speed and boiler demand signals. It controls coal flow by generating speed signal of feeder which conveys coal in hopper to pulverizer, displaying measured coal quantity and providing local auto and manual manipulator (author). 33 figs.

Soot, organics and ultrafine ash from air- and oxy-fired coal combustion

Science.gov (United States)

This paper is concerned with determining the effects of oxy-combustion of coal on the composition of the ultrafine fly ash. To this end, a 10 W externally heated entrained flow furnace was modified to allow the combustion of pulverized coal in flames under practically relevant s...

Effect of Fermentation Methods on the Nutrient Profile and ...

African Journals Online (AJOL)

Objective: This study evaluated the effect of fermentation method on the nutrient profile and organoleptic characteristics of African oil bean seed (Pentaclethra macrophylla Benth). Materials and Methods: Dry and mature African oil bean seeds were cleaned, boiled, dehulled, cooked, sliced/pulverized and fermented to ugba ...

PSO Project 10085

DEFF Research Database (Denmark)

Jappe Frandsen, Flemming; Wu, Hao; Glarborg, Peter

Co-combustion of refuse derived fuels (RDF) with coal in pulverized coal-fired power plants can potentially increase the electrical efficiency of utilizing RDF and reduce the formation of some harmful pollutants such as dioxins. The objective of this project was to provide a general assessment of...

Identification of novel anticancer terpenoids from Prosopis juliflora ...

African Journals Online (AJOL)

Purpose: To identify a novel source of terpenoid anticancer compounds from P. juliflora (Sw.) DC. (Leguminosae) pods as a medicinal substitute for cancer medicines. Methods: The pods were collected, dried and pulverized. The ethanol extract was prepared by maceration. Various phyto-constituents were detected in the ...

Studies of teh phytotoxicity of the seed of phytochemical screening ...

African Journals Online (AJOL)

The phytotoxicity of the seed and phytochemical screening of the leaf of Ricinus communis were investigated. The secondary metabolites in the leaf were screened and identified. The leaves were sun dried, pulverized and sieved. The resulting powdered extract was subjected to phytochemical tests. A proximate analysis ...

Phytochemical constituents and ethnobotany of the leaf extract of ...

African Journals Online (AJOL)

The phytochemical screening and ethno botanical importance of the leaf of Vernonia amygdalina Del. were investigated. The secondary metabolites in the leaf were identified to establish a relationship between them and their therapeutic properties. The leaves were sun dried, pulverized and sieved. The resulting powdered ...

Man-made Black Holes? Can a particle collider be taken too far?

CERN Multimedia

Rupley, Sebastian

2006-01-01

"Can a particle collider be taken too far? That question is being raised about the next-generation Large Hadron Collider (LHC), shown in the photo here. The huge particle pulverizer and accelerator is located at the CERN particle physics laboratory, near Geneva, Switzerland." (1/2 page)

Man-made black holes?

CERN Multimedia

Rupley, Sebastian

2006-01-01

"Can a particle collider be taken too far? That question is being raised about the next-generation Large Hadron Collider (LHC). shown in the photo here. The huge particle pulverizer and accelerator is located at the CERN particle physics laboratory, near Geneva, Switzerland." (1/2 page)

The effect of low-NOx combustion on residual carbon in fly ash and its adsorption capacity for air entrainment admixtures in concrete

DEFF Research Database (Denmark)

Pedersen, Kim Hougaard; Jensen, Anker Degn; Dam-Johansen, Kim

2010-01-01

been combusted in an entrained flow reactor to test the impact of changes in operating conditions and fuel type on the AEA adsorption of ash and NOx formation. Increased oxidizing conditions, obtained by improved fuel-air mixing or higher excess air, decreased the AEA requirements of the produced ash......Fly ash from pulverized coal combustion contains residual carbon that can adsorb the air-entraining admixtures (AEAs) added to control the air entrainment in concrete. This is a problem that has increased by the implementation of low-NOx combustion technologies. In this work, pulverized fuel has...... by up to a factor of 25. This was due to a lower carbon content in the ash and a lower specific AEA adsorptivity of the carbon. The latter was suggested to be caused by changes in the adsorption properties of the unburned char and a decreased formation of soot, which was found to have a large AEA...

Analysis of industrial flame characteristics and constancy study using image processing technique

Directory of Open Access Journals (Sweden)

Bibhuti Bhusan Samantaray

2015-12-01

Full Text Available The study of characterizing and featuring different kinds of flames has become more important than ever in order to increase combustion efficiency and decrease particulate emissions, especially since the study of industrial flames requires more attention. In the present work, different kinds of combustion flames have been characterized by means of digital image processing (DIP in a 500 kW PF pilot swirl burner. A natural gas flame and a set of pulverized fuel flames of coal and biomass have been comparatively analyzed under co-firing conditions. Through DIP, statistical and spectral features of the flame have been extracted and graphically represented as two-dimensional distributions covering the root flame area. Their study and comparison leads to different conclusions about the flame behavior and the effect of co-firing coal and biomass in pulverized fuel flames. Higher oscillation levels in co-firing flames versus coal flames and variations in radiation regimen were noticed when different biomasses are blended with coal and brought under attention.

SVM-based multisensor data fusion for phase concentration measurement in biomass-coal co-combustion

Science.gov (United States)

Wang, Xiaoxin; Hu, Hongli; Jia, Huiqin; Tang, Kaihao

2018-05-01

In this paper, the electrical method combines the electrostatic sensor and capacitance sensor to measure the phase concentration of pulverized coal/biomass/air three-phase flow through data fusion technology. In order to eliminate the effects of flow regimes and improve the accuracy of the phase concentration measurement, the mel frequency cepstrum coefficient features extracted from electrostatic signals are used to train the Continuous Gaussian Mixture Hidden Markov Model (CGHMM) for flow regime identification. Support Vector Machine (SVM) is introduced to establish the concentration information fusion model under identified flow regimes. The CGHMM models and SVM models are transplanted on digital signal processing (DSP) to realize on-line accurate measurement. The DSP flow regime identification time is 1.4 ms, and the concentration predict time is 164 μs, which can fully meet the real-time requirement. The average absolute value of the relative error of the pulverized coal is about 1.5% and that of the biomass is about 2.2%.

Processing method of radiation concrete waste and manufacturing method for radioactive waste solidifying filling mortar

International Nuclear Information System (INIS)

Sukekiyo, Mitsuaki; Okamoto, Masamichi

1998-01-01

Radioactive concrete wastes are crushed and pulverized. Fine solid granular materials caused by the pulverization are classified and the grain size is controlled so that the maximum grain size is 2.5mm, with the grains having a grain size of up to 0.15mm being up to 30% by weight to form fine aggregates. Separated and recovered fine concrete powders are classified and the size of the powder is controlled within a range of from 3,000 to 15,000cm 2 /g which is smaller than cement particles to form fine powders having a stable quality suitable as a mixing agent. The fine aggregates and the mixing agent are mixed to form a filling mortar (filler) for solidifying radioactive wastes. The filling mortar is filled together with other radioactive wastes in a drum to form a waste body in a drum. With such a constitution, crushed radioactive concrete wastes can be reutilized completely. (I.N.)

Co-firing straw with coal in a swirl-stabilized dual-feed burner: modelling and experimental validation

DEFF Research Database (Denmark)

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

2010-01-01

This paper presents a comprehensive computational fluid dynamics (CFD) modelling study of co-firing wheat straw with coal in a 150 kW swirl-stabilized dual-feed burner flow reactor, in which the pulverized straw particles (mean diameter of 451μm) and coal particles (mean diameter of 110.4μm...... conversion. It is found that for pulverized biomass particles of a few hundred microns in diameter the intra-particle heat and mass transfer is a secondary issue at most in their conversion, and the global four-step mechanism of Jones and Lindstedt may be better used in modelling volatiles combustion......-lean core zone; whilst the coal particles are significantly affected by secondary air jet and swirled into the oxygen-rich outer radius with increased residence time (in average, 8.1s for coal particles vs. 5.2s for straw particles in the 3m high reactor). Therefore, a remarkable difference in the overall...

High-performance lithium battery anodes using silicon nanowires.

Science.gov (United States)

Chan, Candace K; Peng, Hailin; Liu, Gao; McIlwrath, Kevin; Zhang, Xiao Feng; Huggins, Robert A; Cui, Yi

2008-01-01

There is great interest in developing rechargeable lithium batteries with higher energy capacity and longer cycle life for applications in portable electronic devices, electric vehicles and implantable medical devices. Silicon is an attractive anode material for lithium batteries because it has a low discharge potential and the highest known theoretical charge capacity (4,200 mAh g(-1); ref. 2). Although this is more than ten times higher than existing graphite anodes and much larger than various nitride and oxide materials, silicon anodes have limited applications because silicon's volume changes by 400% upon insertion and extraction of lithium which results in pulverization and capacity fading. Here, we show that silicon nanowire battery electrodes circumvent these issues as they can accommodate large strain without pulverization, provide good electronic contact and conduction, and display short lithium insertion distances. We achieved the theoretical charge capacity for silicon anodes and maintained a discharge capacity close to 75% of this maximum, with little fading during cycling.

Wireless vibration monitoring in a US coal-fired plant

Energy Technology Data Exchange (ETDEWEB)

Gbur, G.L.; Wier, W.; Bark, T.

2006-07-15

Choosing a reliable wireless systems able to provide data on vibration magnitudes in a coal pulveriser was never going to be easy, so two systems were tested alongside each other. One was the Wireless MCT System produced by SKF Reliability Systems; the other was from an alternative vendor. A replacement wireless vibration monitor was required at the Baldwin Energy Complex near Decartar, Illinois, USA. A single CE-Raymond model 923.RP pulverizer equipped with eight Wilcox on 786A accelerometers was chosen for monitoring. Five days after installation, the pulverizer experienced a failure. The wireless system provided vibration magnitudes to Dynegy's OSI PI Historian software. Analysis of this data coupled with an unsuccessful attempt to adjust the grinding roll, revealed that the number two grinding roll bearing had failed. The SKF Reliability System proved to detect the fault earlier than the non-SKF system and was chosen for the plant. 10 figs., 1 tab.

Contribution to the U$_2$C$_3$ formation by the synthetic reaction and by the decomposition of UC$_2$; Beitrag zur U$_2$C$_3$-bildung nach der synthetischen reaktion und durch zerfall von UC$_2$

Energy Technology Data Exchange (ETDEWEB)

Buschinelli, A. J.A.

1974-06-01

This work is a contribution to the study of the mechanism and of the kinetics of the U$_2$C$_3$ formation by the synthetic reaction. The influences of a mechanical and a thermical pre-treatment of the samples on the reaction kinetics were investigated and discussed taking into account other information from the literature. The relative increasing of the U$_2$C$_3$ nucleation rate due to the pulverization corresponds approximately to the surface enlargement of the pulverized material. The activation energy for the synthetic reaction in powder was found to be 94 +- 7 kcal/mol. The negative influence of nitrogen, oxygen and tungsten on the U$_2$C$_3$ formation was reported. In the decomposition of UC$_2$ to U$_2$C$_3$ and graphite, the influences of the morphology of the graphite precipitate and the fast neutron irradiation on the beginning of the U$_2$C$_3$ formation were also investigated.

Characterization of a U-Mo alloy subjected to direct hydriding of the gamma phase

International Nuclear Information System (INIS)

Balart, Silvia N.; Bruzzoni, Pablo; Granovsky, Marta S.

2003-01-01

The Reduced Enrichment for Research and Test Reactors (RERTR) program has imposed the need to develop plate-type fuel elements based on high density uranium compounds, such as U-Mo alloys. One of the steps in the fabrication of the fuel elements is the pulverization of the fissile material. In the case of the U-Mo alloys, the pulverization can be accomplished through hydriding - dehydriding. Two alternative methods of the hydriding-dehydriding process, namely the selective hydriding in alpha phase (HS-alpha) and the massive hydriding in gamma phase (HM-gamma) are currently being studied at the Comision Nacional de Energia Atomica. The HM-gamma method was reproduced at laboratory scale starting from a U-7 wt % Mo alloy. The hydrided and dehydrided materials were characterized using metallographic techniques, scanning electron microscopy, energy dispersive X-ray analysis and X-ray diffraction. These results are compared with previous results of the HS-alpha method. (author)

Development of bead-type radiophotoluminescence glass dosimeter applicable to various purposes

International Nuclear Information System (INIS)

Sato, F.; Toyota, Y.; Maki, D.; Zushi, N.; Kato, Y.; Yamamoto, T.; Iida, T.

2013-01-01

Bead-type radiophotoluminescence (RPL) glass dosimeters were well fabricated with a gas-particle jet flame system for glass melting-cooling process. A rod of silver-activated phosphate glass was pulverized into micrometer-size particles. Spherical glass particles were formed from the pulverized glass particles in the high-temperature jet flame owing to the surface tension of the glass material. Some groups of spherical glass particles were irradiated with X-rays and their RPL was demonstrably observed for their exposure to UV light. A flexible RPL glass sheet was also made of bead-type RPL glass dosimeters and was useful for radiation imaging. Bead-type RPL glass dosimeters are expected to be used for dose monitoring in highly radioactively-contaminated area. -- Highlights: ► We developed bead-type radiophotoluminescence glass dosimeters. ► Bead-type glass RPL dosimeters are satisfactorily used as radiation dosimeters. ► A flexible RPL glass sheet is made of bead-type RPL glass dosimeters

Mercury speciation in pulverized fuel co-combustion and gasification

NARCIS (Netherlands)

Sable, S.P.

2007-01-01

Coal based power generation is a significant source of mercury emissions to the atmosphere and this has attracted huge attention in the past decade. Recently, the concerns regarding global warming and need for new energy resources introduced the concept of cofiring of biomass and waste as secondary

Detailed model for practical pulverized coal furnaces and gasifiers

Energy Technology Data Exchange (ETDEWEB)

Smith, P.J.; Smoot, L.D.

1989-08-01

This study has been supported by a consortium of nine industrial and governmental sponsors. Work was initiated on May 1, 1985 and completed August 31, 1989. The central objective of this work was to develop, evaluate and apply a practical combustion model for utility boilers, industrial furnaces and gasifiers. Key accomplishments have included: Development of an advanced first-generation, computer model for combustion in three dimensional furnaces; development of a new first generation fouling and slagging submodel; detailed evaluation of an existing NO{sub x} submodel; development and evaluation of an improved radiation submodel; preparation and distribution of a three-volume final report: (a) Volume 1: General Technical Report; (b) Volume 2: PCGC-3 User's Manual; (c) Volume 3: Data Book for Evaluation of Three-Dimensional Combustion Models; and organization of a user's workshop on the three-dimensional code. The furnace computer model developed under this study requires further development before it can be applied generally to all applications; however, it can be used now by specialists for many specific applications, including non-combusting systems and combusting geseous systems. A new combustion center was organized and work was initiated to continue the important research effort initiated by this study. 212 refs., 72 figs., 38 tabs.

Adsorption kinetics of Pb 2+ , Ni 2+ AND Cd 2+ onto powdered ...

African Journals Online (AJOL)

In this paper, the removal of lead, nickel and cadmium from aqueous solution by adsorption was studied. Chicken's eggshells were collected, washed with distilled water, air dried, pulverized, sieved into different particle sizes and stored for use. Powdered eggshells (PES) were separated, its properties were determined and ...

In vitro insulinotropic actions of various extracts of Moringa oleifera ...

African Journals Online (AJOL)

This study investigated the in vitro insulin-releasing and cytotoxic effects of various extracts of Moringa oleifera leaves. Pulverized Moringa oleifera leaves were sequentially extracted with dichloromethane, acetone, ethylacetate and water. Clonal pancreatic beta cells, BRIN-BD11, were grown in an atmosphere of 5% CO2 ...

A FUEL-RICH PRECOMBUSTOR. FIELD EVALUATION OF LOW-EMISSION COAL BURNER TECHNOLOGY ON UTILITY BOILERS - VOLUME IV. ALTERNATE CON- CEPTS FOR SOX, NOX, AND PARTICULATE EMISSIONS CONTROL FROM

Science.gov (United States)

The report gives results a study of the use of precombustors for the simultaneous control of S02, NOx, and ash emissions from coal combustion. In Phase 1, exploratory testing was conducted on a small pilot scale--293 kW (million Btu/hr)-pulverized-coal-fired precombustor to ident...

Briquetting of Palm Kernel Shell | Ugwu | Journal of Applied ...

African Journals Online (AJOL)

In several developing countries, briquettes from agricultural residues contribute significantly to the energy mix especially for small scale and household requirements. In this work, briquettes were produced from Palm kernel shell. This was achieved by carbonising the shell to get the charcoal followed by the pulverization of ...

Pilot plant development of a new catalytic process for improved electrostatic separation of fly-ash in coal fired power plants

Energy Technology Data Exchange (ETDEWEB)

Olivares del Valle, J.; Salvador Martinez, L.; Muniz Baum, B.; Cortes Galeano, V. [University of Seville, Seville (Spain). Chemical and Environmental Engineering Dept.

1996-12-31

A new catalytic process for flue gas conditioning in pulverized coal fired power plants is outlined. Vanadium and platinum catalysts specifically prepared on ceramic honeycomb monoliths to oxidize SO{sub 2} into SO{sub 3} have been tested and evaluated at pilot scale. 10 refs., 3 figs., 2 tabs.

Blood metabolites of intensively reared gravid west African dwarf ...

African Journals Online (AJOL)

Blood metabolites of intensively reared gravid west African dwarf goats fed pulverized biofibre wastes based diets. ... packed cell volume (PCV), haemoglobin (Hb), mean cell volume (MCV) and mean cell haemoglobin (MCH), while goats on PMC/CsP/BG had significantly increased (p<0.05) white blood cell (WBC).

Co-combustion of Fossil Fuels and Waste

DEFF Research Database (Denmark)

Wu, Hao

The Ph.D. thesis deals with the alternative and high efficiency methods of using waste-derived fuels in heat and power production. The focus is on the following subjects: 1) co-combustion of coal and solid recovered fuel (SRF) under pulverized fuel combustion conditions; 2) dust-firing of straw...

Formulation and evaluation of tablet dosage form of Hunteria ...

African Journals Online (AJOL)

The present study was aimed at formulating and evaluating tablet dosage form of Hunteria umbellata (HU) seed aqueous and purified extracts. HU seeds were dried, pulverized and the powder macerated in water to obtain aqueous extract, while alkaloidal extraction process was used to obtain purified extract. Extracts ...

Investigation of the Effect of Alkali Modification of Mucin on Some ...

African Journals Online (AJOL)

The objective of this study was to investigate the effect of alkali treatment of mucin on the mucoadhesive properties and tablet parameters of metronidazole tablets. Mucin was extracted from the African giant snails (Archachatina maginata) by differential precipitation using acetone, air-dried and pulverized. Different portion of ...

A theoretical study using the multiphase numerical simulation technique for effective use of H2 as blast furnaces fuel

Directory of Open Access Journals (Sweden)

Jose Adilson de Castro

2017-07-01

Full Text Available We present a numerical simulation procedure for analyzing hydrogen, oxygen and carbon dioxide gases injections mixed with pulverized coals within the tuyeres of blast furnaces. Effective use of H2 rich gas is highly attractive into the steelmaking blast furnace, considering the possibility of increasing the productivity and decreasing the specific emissions of carbon dioxide becoming the process less intensive in carbon utilization. However, the mixed gas and coal injection is a complex technology since significant changes on the inner temperature and gas flow patterns are expected, beyond to their effects on the chemical reactions and heat exchanges. Focusing on the evaluation of inner furnace status under such complex operation a comprehensive mathematical model has been developed using the multi interaction multiple phase theory. The BF, considered as a multiphase reactor, treats the lump solids (sinter, small coke, pellets, granular coke and iron ores, gas, liquids metal and slag and pulverized coal phases. The governing conservation equations are formulated for momentum, mass, chemical species and energy and simultaneously discretized using the numerical method of finite volumes. We verified the model with a reference operational condition using pulverized coal of 215 kg per ton of hot metal (kg thm−1. Thus, combined injections of varying concentrations of gaseous fuels with H2, O2 and CO2 are simulated with 220 kg thm−1 and 250 kg thm−1 coals injection. Theoretical analysis showed that stable operations conditions could be achieved with productivity increase of 60%. Finally, we demonstrated that the net carbon utilization per ton of hot metal decreased 12%.

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

Energy Technology Data Exchange (ETDEWEB)

Lans, R.P. van der

1997-04-01

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

Dissolution of uranium oxide TBP-HNO3 complex

International Nuclear Information System (INIS)

Mizuno, Mineo; Kosaka, Yuji; Mori, Yukihide; Shimada, Takashi

2002-12-01

As a head end process for the pulverization of the spent fuel, the mechanical method (the shredder method) and the pyro-chemical method (oxidisation heat-treatment) have been examined. UO 2 is a main ingredient of Uranium oxide powder by the mechanical method, and U 3 O 8 is that by the pyro-chemical method. Moreover, the particle size of the pulverized powder depend on the conditions of the pulverizing process. As it was considered that the difference of dissolution rates of samples was caused by the difference of sample chemical forms and dissolution temperature, parametric surveys on chemical form and particle size of powder and dissolution temperature were carried out, and the following results were obtained. 1) The remarkable difference of dissolution rate between U 3 O 8 powder (average particle size 3.7 μm) and UO 2 powder (average particle size 2.4 μm) which have comparatively similar particle size was not observed. 2) It was confirmed that the dissolution rate became lower according to the particle size increase (average particle size 2.4 μm-1 mm). And it was considered that dissolution rate had strong dependency on particle size, according to the results that the powder with 1 mm particle size did not dissolute completely after 5 hours test. 3) The temperature dependency of the dissolution rate was confirmed by dissolution test with UO 2 powder (average particle size 2.4 μm-1 mm). The higher dissolution rate was obtained in the higher dissolution temperature, and 11 kcal/mol was obtained as activation energy of dissolution. 4) In the dissolution test of UO 2 powder, the nitric acid concentration started to change earlier than that of U 3 O 8 powder and concentration change range became larger compared with that in the dissolution test of U 3 O 8 powder. It was considered that those differences were caused by difference in mole ratio of Uranium and nitric acid which are consumed in the dissolution reaction (3:7 for U 3 O 8 , 3:8 for UO 2 ). 5) In case

40 CFR 60.50Da - Compliance determination procedures and methods.

Science.gov (United States)

2010-07-01

... probe and filter holder heating system in the sampling train may be set to provide an average gas... correction factor, integrated or grab sampling and analysis procedures of Method 3B of appendix A of this... fuel oil, etc.), coal pulverizers, and bottom and fly ash interactions. This determination is optional...

American Involvement in the Filipino Resistance Movement on Mindanao during the Japanese Occupation, 1942-1945

Science.gov (United States)

1982-05-20

vinegar and brine, and ctied in the sun. The jerky-like substance, called tapa, cured in two days and would remain preserved indefinitely. 207 Another...coconut tree, then fermented it with pulverized tanbark from a mangrove tree. Alcohol was extracted by using a still made from a Socony can with bamboo

Roselle calyx (Zoborodo) as a substitute to organic indicator (methyl ...

African Journals Online (AJOL)

Roselle calyx samples were dried, pulverized into powder and extracted with distilled water for 24 hours by maceration method. The acidity and alkalinity indicator properties of the extracts were tested with prepared acid and base solutions. The results showed colour change with all the samples. But titration using the ...

Hypolipidemic Activity of Prosopis cineraria L (Druce) Fruit Extract ...

African Journals Online (AJOL)

Purpose: To investigate the hypolipidemic potential of the 70 % ethanol fruit extract of Prosopis cineraria (Fabaceae) (Et. PCF) in triton-induced hyperlipidemia in rats. Methods: Et-PCF was obtained by pulverizing whole dried fruits and extracting with 70 % ethanol. Adult Sprague Dawley rats were divided into six groups of ...

Untitled

African Journals Online (AJOL)

Health concerns over prophylactic abuse of herbal drugs are worrisonne. .... Behavioral signs of acute toxicity were light greenish solid extract and was stored at ... Figure 1: Fresh plant – and pulverized / sieved sample of A. godseffiana. .... Togligible signs of incrod urinary polo and negligible signs of vacoulation in the liver.

Effects of legume cover crop and sub-soiling on soil properties and Maize (Zea mays L) growth in semi arid area of Machakos district, Kenya = Efecto del cultivo de cobertua y el subsolado sobre las propiedades del suelo y crecimiento de maiz (Zea mays L.) en la region semi arida de Machakos, Kenia

NARCIS (Netherlands)

Karuma, A.; Gachene, C.K.K.; Gicheru, P.; Mwangombe, A.W.; Mwangi, H.W.; Clavel, D.; Verhagen, A.; Kaufmann, Von R.; Francis, J.; Ekaya, W.

2011-01-01

Low crop yields in the semi arid areas of Kenya have been attributed to, among other factors, low soil fertility, low farm inputs, labour constraints and inappropriate tillage practices that lead to pulverized soils. The aim of this study was to determine the effects of legume cover crops (LCC) on

Analgesic and Anti-inflammatory Effects of the Aqueous Leaf Extract ...

African Journals Online (AJOL)

ADOWIE PERE

suggest that the extract possesses anti-inflammatory and analgesic effects, which may be mediated solely by ... were then carefully separated from the stem; air dried for 7 days and pulverized using an electric mill. ... venier caliper, baseline measurement of the right hind .... to the release of mast cell autacoids like histamine.

Study on the combustion properties of bio-coal briquette blends of ...

African Journals Online (AJOL)

This study was carried out to investigate the properties of bio-coal briquette produced from blending cassava stalk and coal. The cassava stalk and coal lumps were carbonized at 160 oC, pulverized and used to produce biocoal briquettes of 10 %, 20 %, 30 %, 40 %, 50 %, 60 %,70 %, 80 %, 90 % and 100 % biomasses.

Hot pressing effect on (Bi 0.25 Sb 0.75 ) 2 Te 3 mechanical and ...

Indian Academy of Sciences (India)

Hot pressing effect on (Bi0.25Sb0.75)2Te3 mechanical and thermoelectric properties ... The crystal of this compound was prepared, pulverized in a particle size ratio of 64% ... microscopy and, for only once successful attempt, atomic force microscopy. The acquired images ensured to show homogeneous structures for hot ...

Not every ecotax is good for the environment

International Nuclear Information System (INIS)

Brinkman, L.; Huppes, G.

1999-01-01

Although coal gasification is the cleanest form of coal-fired electric power generation it's advantage is not reflected in the environmental taxes in the Netherlands ('ecotax'). Recommendations are given to improve the ecotax in order to better reflect the advantages of a coal gasifier over e.g. a pulverized coal plant. 9 refs

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

NARCIS (Netherlands)

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

2013-01-01

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

40 CFR Appendix A to Subpart M of... - Interpretive Rule Governing Roof Removal Operations

Science.gov (United States)

2010-07-01

...-containing material (ACM) is material containing more than one percent asbestos as determined using the... NESHAP classifies ACM as either “friable” or “nonfriable”. Friable ACM is ACM that, when dry, can be crumbled, pulverized or reduced to powder by hand pressure. Nonfriable ACM is ACM that, when dry, cannot be...

Estimation of Moisture Content in Coal in Coal Mills

DEFF Research Database (Denmark)

Odgaard, Peter Fogh; Mataji, B.

the moisture content of the coal is proposed based on a simple dynamic energy model of a coal mill, which pulverizes and dries the coal before it is burned in the boiler. An optimal unknown input observer is designed to estimate the moisture content based on an energy balance model. The designed moisture...

Estimation of Moisture Content in Coal in Coal Mills

DEFF Research Database (Denmark)

Odgaard, Peter Fogh; Mataji, Babak

2006-01-01

the moisture content of the coal is proposed based on a simple dynamic energy model of a coal mill, which pulverizes and dries the coal before it is burned in the boiler. An optimal unknown input observer is designed to estimate the moisture content based on an energy balance model. The designed moisture...

21 CFR 163.112 - Breakfast cocoa.

Science.gov (United States)

2010-04-01

... CONSUMPTION CACAO PRODUCTS Requirements for Specific Standardized Cacao Products § 163.112 Breakfast cocoa. (a) Description. (1) Breakfast cocoa is the food prepared by pulverizing the material remaining after part of the... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Breakfast cocoa. 163.112 Section 163.112 Food and...

Adeneye et al., Afr J Tradit Complement Altern Med. (2014) 11(2 ...

African Journals Online (AJOL)

cadewumi

42.4% of those with arthritis) had arthritis-attributable-to-activity-limitation (AAAL) and with an aging population this figure is expected to rise. (Woolf and Pfleger ... West Africa where decoctions made from its pulverized leaves are used for the local treatment of rheumatic pains, fever, wounds and diarrhea. (Ogungbamila and ...

Determination of ulcer protecting effect of ethanol extract of ...

African Journals Online (AJOL)

Ethanol extract of dietary vegetable, Gongronema latifolium, was evaluated for anti-ulcer activity. The extract was obtained from air-dried, pulverized leaves of the plant following its maceration in ethanol, filteration with Whatman No. 1 filter paper and drying at 110°C. Fractionation of the dry crude ethanol extract was ...

OPTIMUM DRYING PROCESS. Best drying conditions to grind fruits and vegetables

OpenAIRE

Pina Laguna, Meritxell

2013-01-01

World’s population is increasing annually, thereby increasing world’s food demand. Considering current trends, changes in food production must be done in order to meet the estimated future demand. This problem and its possible solutions such as drying or pulverizing the foods, in which this thesis is focused on, are described in detail below.

10 CFR 504.6 - Prohibitions by order (case-by-case).

Science.gov (United States)

2010-01-01

... handling equipment, such as conveyor belts, pulverizers, or unloading facilities, bears on the issue of a... whether the unit was expressly designed to burn that fuel or whether it ever actually did burn it), but is... required to meet air quality requirements. 4 4 A unit designed to burn natural gas shall be presumed to...

Download this PDF file

African Journals Online (AJOL)

ES Obe

connected by a clutch arrangement to the motor shaft of a disused electric blender and carefully secured in two bearings to run smoothly. The disc may spin at any of the 14 blender speeds designated in the increasing order as whip, stir, puree, beat, aerate, crumb, chop, grind, mix, grate, pulverize, churn, blend and liquefy.

Influence of composition on phase occurrence during charge process of AB5+x Ni-MH negative electrode materials

International Nuclear Information System (INIS)

Vivet, S.; Latroche, M.; Chabre, Y.; Joubert, J.-M.; Knosp, B.; Percheron-Guegan, A.

2005-01-01

Multi-substituted LaNi 5 -type alloys (AB 5+ x ) are widely used as negative electrode materials in commercial Ni-MH batteries. Cobalt substitution on Ni sites allows to enhance battery cycle life by reducing alloy pulverization induced by hydrogen cycling. This improvement is attributed to the occurrence of a three-phase process (α, β and γ) during electrochemical hydrogen loading. In order to better understand the effect of the composition on the phase occurrence and to reduce the rate of costly cobalt, an in situ neutron diffraction study has been performed at room temperature during electrochemical charge of two different electrode materials MmNi 4.07 Mn 0.63 Al 0.2 M 0.4 with M=Fe and Mn and B/A=5.3. These cobalt free compounds show cycle life comparable to that of commercial materials. The results show that three phases are also observed for these samples. The γ-phase content depends on M and is higher for M=Fe than for M=Mn. These results are related to the improved cycle lives and to the alloy pulverization process

Transformations of inorganic coal constituents in combustion systems. Volume 1, sections 1--5: Final report

Energy Technology Data Exchange (ETDEWEB)

Helble, J.J. [ed.; Srinivasachar, S.; Wilemski, G.; Boni, A.A. [PSI Technology Co., Andover, MA (United States); Kang, Shin-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. [Massachusetts Inst. of Tech., Cambridge, MA (United States); Peterson, T.W.; Wendt, J.O.L.; Gallagher, N.B.; Bool, L. [Arizona Univ., Tucson, AZ (United States); Huggins, F.E.; Huffman, G.P.; Shah, N.; Shah, A. [Kentucky Univ., Lexington, KY (United States)

1992-11-01

The inorganic constituents or ash contained in pulverized coal significantly increase the environmental and economic costs of coal utilization. For example, ash particles produced during combustion may deposit on heat transfer surfaces, decreasing heat transfer rates and increasing maintenance costs. The minimization of particulate emissions often requires the installation of cleanup devices such as electrostatic precipitators, also adding to the expense of coal utilization. Despite these costly problems, a comprehensive assessment of the ash formation and had never been attempted. At the start of this program, it was hypothesized that ash deposition and ash particle emissions both depended upon the size and chemical composition of individual ash particles. Questions such as: What determines the size of individual ash particles? What determines their composition? Whether or not particles deposit? How combustion conditions, including reactor size, affect these processes? remained to be answered. In this 6-year multidisciplinary study, these issues were addressed in detail. The ambitious overall goal was the development of a comprehensive model to predict the size and chemical composition distributions of ash produced during pulverized coal combustion. Results are described.

Transformations of inorganic coal constituents in combustion systems

Energy Technology Data Exchange (ETDEWEB)

Helble, J.J. (ed.); Srinivasachar, S.; Wilemski, G.; Boni, A.A. (PSI Technology Co., Andover, MA (United States)); Kang, Shin-Gyoo; Sarofim, A.F.; Graham, K.A.; Beer, J.M. (Massachusetts Inst. of Tech., Cambridge, MA (United States)); Peterson, T.W.; Wendt, J.O.L.; Gallagher, N.B.; Bool, L. (Arizona Univ., Tucson, AZ (United States)); Huggins, F.E.; Huffman, G.P.; Shah, N.; Shah, A. (Kentucky Univ., Lexingt

1992-11-01

The inorganic constituents or ash contained in pulverized coal significantly increase the environmental and economic costs of coal utilization. For example, ash particles produced during combustion may deposit on heat transfer surfaces, decreasing heat transfer rates and increasing maintenance costs. The minimization of particulate emissions often requires the installation of cleanup devices such as electrostatic precipitators, also adding to the expense of coal utilization. Despite these costly problems, a comprehensive assessment of the ash formation and had never been attempted. At the start of this program, it was hypothesized that ash deposition and ash particle emissions both depended upon the size and chemical composition of individual ash particles. Questions such as: What determines the size of individual ash particles What determines their composition Whether or not particles deposit How combustion conditions, including reactor size, affect these processes remained to be answered. In this 6-year multidisciplinary study, these issues were addressed in detail. The ambitious overall goal was the development of a comprehensive model to predict the size and chemical composition distributions of ash produced during pulverized coal combustion. Results are described.

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

Energy Technology Data Exchange (ETDEWEB)

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

2013-07-01

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

FY1998 research report on the R and D on recycling technology. Part 1; 1998 nendo recycle nado kankyo gijutsu kekyu kaihatsu seika hokokusho. 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

This project aims to develop recycling technology for reduction of environmental burden caused by waste, and promotion of recycling of wastes. As for advanced recycling technology for PET bottles, the facility was improved for improvement of a facility operability and product quality. Study was made on the effect of a raw bale quality and recycled flake colors on a product quality, the forming test with PS or PET labels, and the concentration and effect of washing liquid circulated in flake washing process. As for recycling technology of hard-to-dispose waste plastics, facility improvement and demonstration test were made for continuous operation of dry-distillation/gasification of shredder dusts and separation of nonferrous metals and glass. Study was also made on pulverizing and recycling technologies of FRP bath tubs, and such pulverization costs were estimated. As for production technology of chemical feed and fuel from wastes, study was made on removal technology of non-flammable substances, development of alkaline additives, reacting condition, development of reactors, and use technology as chemical feed. (NEDO)

Burnout synergic or inhibiting effects in combustion assays of coal/sawdust blends

Energy Technology Data Exchange (ETDEWEB)

Ximena Garcia; Ximena Matus; Claudia Ulloa; Alfredo L. Gordon [University of Concepcion, Concepcion (Chile). Dept. of Chemical Engineering

2007-07-01

Characterization of chars and charcoal and combustion assays of coal/ pine sawdust blends were carried on to evaluate the burnout, under conditions similar to those found in pulverized coal combustion. A drop tube furnace (DTF) was used to generate chars from three coals of different rank (Bitsch, a lignite; Lemington, a bituminous HV coal; and LD, a semianthracite) and charcoal from sawdust (S). Burning profiles, as well as morphological and optical characterization of these chars were obtained and discussed. Pulverized samples of pure constituents and sawdust/coal blends (5, 10 and 20%wt of S) were burned in the DTF reactor. Samples of combustion residues were collected for characterization. Depending on blend composition and the rank of the coal being blended, positive and negative deviations with respect to the expected weighted average value of the burnout were measured. This behavior is related both, to the duration of the step by which simultaneous burning of char and charcoal take place, and to the sawdust content in the blend. The optical analysis of combustion residues supports this conclusion. 7 refs., 6 figs., 3 tabs.

Next-generation coal utilization technology development study. Environmentally-friendly coal combustion technology; O2/CO2 combustion technology; Sekitan riyo jisedai gijutsu kaihatsu chosa. Kankyo chowagata sekitan nensho gijutsu (sanso nensho gijutsu)

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-03-01

For the purpose of developing combustion systems in which environmental pollutants are less emitted from coal-fired boilers, conducted in fiscal 1994 were a study of load followability of oxygen producing equipment, and element and basic tests on oxygen combustion systems. Dynamic simulations were made to confirm load followability of low-purity oxygen producing equipment. Further, a test was made on starting time of oxygen producing equipment. As a result of the simulation, favorable load followability was confirmed except for some of the process. The width of variation of the product oxygen purity was {plus_minus} 0.7% at maximum. In the element test on oxygen combustion systems, an experiment on the oxygen combustion using pulverized coal was conducted to study heat collection characteristics of furnace and response to multi-kind of coal. A study of balance of S content, experiments on characteristics of crushing/transporting pulverized coal, etc. were added. There were seen no peculiar differences in CO2 transport and air transport. 216 figs., 31 tabs.

Nitrogen oxide emissions - one of the most important characteristics of power generating boilers

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R. (Vsesoyuznyi Teplotekhnicheskii Institut (USSR))

1989-05-01

Discusses in some detail optimum locations, equipment and sequence for measuring NO{sub x} emissions and, with specific reference to operational factors and structural features, examines ways to achieve efficient and cost effective reduction in emissions. One method for reducing NO{sub x} concentrations with solid fuel combustion, e.g. Kuznetsk black coal combustion, is to alter the proportion of primary air and the output flow rates of the secondary and primary air. Graph demonstrates the successful result of coarsening the pulverized Ekhibastuz coal burnt in the BKZ-420-140 boiler in the Karaganda TEhTs-3 power plant. Suggested structural measures include modifying burners, two- and three-stage combustion, conversion to solid slag removal or to circulating fluidized bed combustion. Also mentions the need to reduce NO{sub x} emissions in unfavorable weather conditions. Finally suggests converting pulverized coal boilers to burn gas, disconnecting or reducing the load of boilers with low exhaust-gas stacks and increasing the number of boilers with high exhaust-gas stacks to reduce ground level NO{sub x} concentrations. 4 refs.

Morphology study on the depleted uranium as hydriding/dehydriding cycles

Energy Technology Data Exchange (ETDEWEB)

Chung, Dong-you, E-mail: dongyou@nfri.re.kr [National Fusion Research Institute, Daejeon (Korea, Republic of); Yun, Sei-Hun; Kang, Hyun-Goo; Chang, Min Ho; Oh, Yun Hee [National Fusion Research Institute, Daejeon (Korea, Republic of); Kang, Kweon Ho; Woo, Yoon Myung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-11-01

Depleted Uranium (DU) is one of the strongest candidates as a getter material of hydrogen isotopes in the nuclear fusion reactor. In this work, small DU lump specimen with 99.8% purity was prepared for observation of morphology variation as hydriding/dehydriding cycles. Hydriding/dehydriding of DU was carried out more than 10 cycles for powder preparation. The pulverized DU specimen was safely handled in the glove box under Argon gas condition to minimize contact with oxygen and humidity. The morphology change according to hydriding/dehydriding cycles was observed by visual cell reactor, optical microscope and scanning electron microscope. The first hydriding of the small DU sample has progressed slowly with surface enlargement and volume expansion as time passes. After third hydriding/dehydriding cycles, most of DU was pulverized. The powder fineness of DU developed as hydriding/dehydriding cycle progresses. But the agglomerates of fine DU particles were observed. It was confirmed that the DU particles exist as porous agglomerates. And the particle agglomerate shows poor fluidity and even has the cohesive force.

Análisis de la operación del horno alto mediante la exergía térmica

Directory of Open Access Journals (Sweden)

Babich, A.

1998-05-01

Full Text Available In order to know the blast furnace thermic state, the thermic exergy can be used, which considers the temperatures level of the process. The magnitude analysis of thermic exergy for blast furnace operation using pulverized coal, natural gas and oxigen injection by tuyeres, shows that natural gas injection is less effective than pulverized coal and enriched blast with oxygen simultaneous injection.

Para conocer el estado térmico del horno alto se puede utilizar la exergía térmica, que considera el nivel de temperaturas del proceso. El análisis de la magnitud de la exergía térmica, para la operación del horno alto, utilizando inyecciones por toberas de carbón pulverizado, de gas natural y viento enriquecido en oxígeno, en ambos casos muestra que la inyección de gas natural es menos efectiva que la inyección simultánea de carbón pulverizado y viento enriquecido con oxígeno.

Properties of concrete modified with waste Low Density Polyethylene and saw dust ash

Science.gov (United States)

Srimanikandan, P.; Sreenath, S.

2017-07-01

The increase in industrialization creates need for disposal of large quantity of by-products. To overcome the difficulty of disposal, these by-products can be used as a replacement for raw material. In this concern, non-conventional industrial wastes such as plastic bags, PET bottles, pulverized waste Low Density Polyethylene (LDPE) and biological waste such as saw-dust ash, coconut coir were used as a replacement in concrete. In this project, saw-dust ash and pulverized waste LDPE were introduced as the partial replacement for cement and fine aggregates respectively. 0%, 5%, 10%, 15% and 20% of sand by volume was replaced with LDPE and 0%, 1%, 3%, 5% and 10% of cement by volume was replaced with saw dust ash. Standard cube, cylinder and prism specimens were cast to assess the compressive strength, split tensile strength and flexural strength of modified concrete after 28 days of curing. Optimum percentage of replacement was found by comparing the test results. The mix with 5% of LDPE and 3% of saw dust ash showed a better result among the other mixes.

Phosphine from rocks: mechanically driven phosphate reduction?

Science.gov (United States)

Glindemann, Dietmar; Edwards, Marc; Morgenstern, Peter

2005-11-01

Natural rock and mineral samples released trace amounts of phosphine during dissolution in mineral acid. An order of magnitude more phosphine (average 1982 ng PH3 kg rock and maximum 6673 ng PH3/kg rock) is released from pulverized rock samples (basalt, gneiss, granite, clay, quartzitic pebbles, or marble). Phosphine was correlated to hardness and mechanical pulverization energy of the rocks. The yield of PH3 ranged from 0 to 0.01% of the total P content of the dissolved rock. Strong circumstantial evidence was gathered for reduction of phosphate in the rock via mechanochemical or "tribochemical" weathering at quartz and calcite/marble inclusions. Artificial reproduction of this mechanism by rubbing quartz rods coated with apatite-phosphate to the point of visible triboluminescence, led to detection of more than 70 000 ng/kg PH3 in the apatite. This reaction pathway may be considered a mechano-chemical analogue of phosphate reduction from lightning or electrical discharges and may contribute to phosphine production via tectonic forces and processing of rocks.

Result of design and test operation of a coal boiler at Hyogo Refinery

Energy Technology Data Exchange (ETDEWEB)

Miura, Yasuhiko; Sato, Noriyuki

1987-05-01

This boiler is the first coal boiler for the oil refineries in Japan (Installed in Oct., 1986 at Idemitsu Petrochemical Co.) Causes for using coal as a fuel are a conversion to less expensive fuel and offering a technical service to the users of coal through the combustion of coal and learning of a handling technique. The type of boiler is Babcock single barrel radiant type and has 150 t/d capacity with single fuel combustion of coal. Auxiliary equipments are a pulverizer, a transportation and storage unit, a denitration unit, a dust collector, a desulfurization unit, and an ash disposal unit. Main considerations in the design are measures for the security of finely pulverized coal, clogging prevention for coal and ash. A test operation revealed 7 % of combustible loss and 160 - 250 ppm of NOx content at a charge inlet of denitration unit. Actual operation exhibited no clogging at the denitration unit of troubles due to scaling. Design for raw materials is to blend 4 imported coals (from Australia and Canada, etc) and 3 Japanese ones. (7 figs, 2 tabs)

An update on blast furnace granular coal injection

Energy Technology Data Exchange (ETDEWEB)

Hill, D.G. [Bethlehem Steel Corp., Burns Harbor, IN (United States); Strayer, T.J.; Bouman, R.W. [Bethlehem Steel Corp., PA (United States)

1997-12-31

A blast furnace coal injection system has been constructed and is being used on the furnace at the Burns Harbor Division of Bethlehem Steel. The injection system was designed to deliver both granular (coarse) and pulverized (fine) coal. Construction was completed on schedule in early 1995. Coal injection rates on the two Burns Harbor furnaces were increased throughout 1995 and was over 200 lbs/ton on C furnace in September. The injection rate on C furnace reached 270 lbs/ton by mid-1996. A comparison of high volatile and low volatile coals as injectants shows that low volatile coal replaces more coke and results in a better blast furnace operation. The replacement ratio with low volatile coal is 0.96 lbs coke per pound of coal. A major conclusion of the work to date is that granular coal injection performs very well in large blast furnaces. Future testing will include a processed sub-bituminous coal, a high ash coal and a direct comparison of granular versus pulverized coal injection.

Antimosquito Phenylpropenoids from the Stem and Root Barks of ...

African Journals Online (AJOL)

Michael Horsfall

The plant species was identified on site and its identity was further confirmed at the Herbarium of the. Department of Botany, University of Dar es Salaam, where a voucher specimen is deposited. Extraction and Isolation: The air dried and pulverized root and stem barks were extracted sequentially with CHCl3 and MeOH, 2 x ...

Particle-based characterisation of pulverised coals and chars for carbon burnout studies

Energy Technology Data Exchange (ETDEWEB)

Gibbins, J.R.; Seitz, M.H.; Kennedy, S.M.; Beeley, T.J.; Riley, G.S. [Imperial College of Science, Technology and Medicine, London (United Kingdom). Mechanical Engineering Department

1999-07-01

The study of individual particle properties, as opposed to averaged behaviour of differing particles, was carried out for the combustion of coals and chars using optical microscopy and digital image processing. Chars from entrained flow reactors and corresponding pulverized fuel samples were characterized to examine possible char particle origins for real heterogeneous particles. 7 refs., 5 figs., 1 tab.

Physical Properties of Biomass Fuel Briquette from Oil Palm ...

African Journals Online (AJOL)

ADOWIE PERE

of fuel briquettes in this study in order to supplement the energy mix of the nation. PKS was pulverized ... fossil fuel in the world market is impacting negatively ... useful products that can be applied in many sectors ... at 350 µm, 250 µm and 150 µm with Octagon digital ... formula is one of the models developed to accurately.

Advanced pulverized-coal power plants: A U.S. export opportunity

International Nuclear Information System (INIS)

Ruth, L.A.; Ramezan, M.; Izsak, M.S.

1995-01-01

This paper provides an overview of Low Emission Boiler System (LEBS) power generation systems and its potential for generating power worldwide. Based on the fuel availability, power requirements, and environmental regulations, countries have been identified that need to build advanced, clean, efficient, and economical power generation, systems. It is predicted that ''more electrical generation capacity will be built over the next 25 years than was built in the previous century''. For example, China and India alone, with less than 10% of today's demand, plan to build what would amount to a quarter of the world's new capacity. For the near- to mid-term, the LEBS program of Combustion 2000 has the promise to fill some of the needs of the international coal-fired power generation market. The high efficiency of LEBS, coupled with the use of advanced, proven technologies and low emissions, make it a strong candidate for export to those areas whose need for additional power is greatest. LEBS is a highly advanced version of conventional coal-based power plants that have been utilized throughout the world for decades. LEBS employs proven technologies and doesn't require gasification and/or an unconventional combustion environment (e.g., fluidized bed). LEBS is viewed by the utility industry as technically acceptable and commercially feasible

Processing woody debris biomass for co-milling with pulverized coal

Science.gov (United States)

Dana Mitchell; Bob Rummer

2007-01-01

The USDA, Forest Service, Forest Products Lab funds several grants each year for the purpose of studying woody biomass utilization. One selected project proposed removing small diameter stems and unmerchantable woody material from National Forest lands and delivering it to a coal-fired power plant in Alabama for energy conversion. The Alabama Power Company...

Simulating the structure of gypsum composites using pulverized basalt waste

Directory of Open Access Journals (Sweden)

Buryanov Аleksandr

2017-01-01

Full Text Available This paper examines the possibility of simulating the structure of gypsum composite modified with basalt dust waste to make materials and products based on it. Structural simulating of the topological space in gypsum modified composite by optimizing its grain-size composition highly improves its physical and mechanical properties. Strength and density tests have confirmed the results of the simulation. The properties of modified gypsum materials are improved by obtaining of denser particle packing in the presence of hemihydrate of finely dispersed basalt and plasticizer particles in the system, and by engaging basalt waste in the structuring process of modified gypsum stone.

Maailmamajanduse konjunktuur : 2006. a. II ja III kv / B Pulver

Index Scriptorium Estoniae

Pulver, B

2006-01-01

Lühiülevaade maailmamajanduse konjunktuurist 2006. aasta II ja III kvartalis on koostatud Müncheni Majandusuuringute Instituudi väljaande World Economic Survey nr 92 alusel. 2006. a. aprilli vaatlus näitas maailma majanduskliima paranemist. Tabelid: Ekspertide hinnangud aprillis 2006 (max=9); Arenenud riikide majandusindikaatorid; Konjunktuuribaromeetrite kindlustunde indikaatorid Euroopa Liidu maades

Tritium enrichment in aqueous phase by catalytic isotopic exchange

International Nuclear Information System (INIS)

Schindewolf, U.

1983-01-01

At normal pressure, the most promising enrichment method appears to be an inverse current exchanger system using electrolysis at the bottom of the inverse current column apparatus and recombination in an oxyhydrogen gas flame at the top of the column apparatus. A hydrophobic catalyst is used which is made of a pulverized mix of platinized activated carbon and PTFE. (DG) [de

Experimental modeling of swirl flows in power plants

Science.gov (United States)

Shtork, S. I.; Litvinov, I. V.; Gesheva, E. S.; Tsoy, M. A.; Skripkin, S. G.

2018-03-01

The article presents an overview of the methods and approaches to experimental modeling of various thermal and hydropower units - furnaces of pulverized coal boilers and flow-through elements of hydro turbines. The presented modeling approaches based on a combination of experimentation and rapid prototyping of working parts may be useful in optimizing energy equipment to improve safety and efficiency of industrial energy systems.

Rollerjaw Rock Crusher

Science.gov (United States)

Peters, Gregory; Brown, Kyle; Fuerstenau, Stephen

2009-01-01

The rollerjaw rock crusher melds the concepts of jaw crushing and roll crushing long employed in the mining and rock-crushing industries. Rollerjaw rock crushers have been proposed for inclusion in geological exploration missions on Mars, where they would be used to pulverize rock samples into powders in the tens of micrometer particle size range required for analysis by scientific instruments.

Effectiveness of artificial intelligence methods in applications to burning optimization and coal mills diagnostics on the basis of IASE's experiences in Turow Power Plant

Energy Technology Data Exchange (ETDEWEB)

Pollak, J.; Wozniak, A.W.; Dynia, Z.; Lipanowicz, T.

2004-07-01

Modern methods referred to as 'artificial intelligence' have been applied to combustion optimization and implementation of selected diagnostic functions for the milling system of a pulverized lignite-fired boiler. The results of combustion optimization have shown significant improvement of efficiency and reduction of NO, emission. Fuzzy logic has been used to develop, among other things, a fan mill overload detection system.

Microfine coal firing results from a retrofit gas/oil-designed industrial boiler

Energy Technology Data Exchange (ETDEWEB)

Patel, R.; Borio, R.W.; Liljedahl, G. [Combustion Engineering, Inc., Windsor, CT (United States)] [and others

1995-11-01

Under US Department of Energy, Pittsburgh Energy Technology Center (PETC) support, the development of a High Efficiency Advanced Coal Combustor (HEACC) has been in progress since 1987 at the ABB Power Plant Laboratories. The initial work on this concept produced an advanced coal firing system that was capable of firing both water-based and dry pulverized coal in an industrial boiler environment.

Avaliação do sistema de pulverização com funcionamento intermitente, acoplado ao pivô central, Notliada Evaluation of a pulverization system, with emitters working in intermittent mode, on a Notliada central pivot

Directory of Open Access Journals (Sweden)

Robson A. Armindo

2009-02-01

Full Text Available Teve-se como objetivo, no presente trabalho, avaliar o desvio existente entre as vazões estimadas e observadas dos emissores presentes no sistema de pulverização acoplado ao pivô central, Notliada. Os testes foram realizados em um protótipo do sistema, montado em uma área anexa ao Laboratório de Hidráulica do Departamento de Engenharia Rural (LER pertencente à Escola Superior de Agricultura "Luiz de Queiroz" - ESALQ/USP. Os resultados obtidos mostraram que os modelos gerados dos desvios relativos existentes entre as vazões estimadas e observadas em função da freqüência de operação da válvula solenóide apresentaram excelentes índices de precisão e exatidão. Encontrou-se um tempo mínimo de 1,0 s em que a válvula solenóide deve permanecer ligada para os emissores de diâmetro 1,212 (preto, 1,016 (vermelho e 1,020 mm (laranja; para o emissor de diâmetro 0,621mm (azul, esse tempo mínimo encontrado foi de 1,4 s. A mesma válvula pode permanecer desligada durante qualquer intervalo de tempo entre 3 e 9 s para todos os emissores testados. Os emissores preto e laranja indicaram índices inaceitáveis de uniformidade de aplicação para tempos de acionamento menores que 0,7 s. Os emissores azul e vermelho indicaram excelentes índices para qualquer intervalo de tempo de acionamento. Enfim, todos os emissores indicaram excelentes índices de uniformidade para todos os intervalos de tempo de desligamento da válvula solenóide testados.The aim of this study was to evaluate the difference between estimated and observed emitter flow rates presented by the Notliada pulverization system. The research was undertaken in the Hydraulic Laboratory/Rural Engineering Department at "Luiz de Queiroz" College of Agriculture, University of São Paulo, Brazil. The proposed models showed excellent precision and accuracy indexes. It was determine that emitters of diameter 1.212 (black, 1.016 (red and 1.020 mm (orange; the solenoid valve must stay

Utilization of Mineral Wools as Alkali-Activated Material Precursor

Directory of Open Access Journals (Sweden)

Juho Yliniemi

2016-04-01

Full Text Available Mineral wools are the most common insulation materials in buildings worldwide. However, mineral wool waste is often considered unrecyclable because of its fibrous nature and low density. In this paper, rock wool (RW and glass wool (GW were studied as alkali-activated material precursors without any additional co-binders. Both mineral wools were pulverized by a vibratory disc mill in order to remove the fibrous nature of the material. The pulverized mineral wools were then alkali-activated with a sodium aluminate solution. Compressive strengths of up to 30.0 MPa and 48.7 MPa were measured for RW and GW, respectively, with high flexural strengths measured for both (20.1 MPa for RW and 13.2 MPa for GW. The resulting alkali-activated matrix was a composite-type in which partly-dissolved fibers were dispersed. In addition to the amorphous material, sodium aluminate silicate hydroxide hydrate and magnesium aluminum hydroxide carbonate phases were identified in the alkali-activated RW samples. The only crystalline phase in the GW samples was sodium aluminum silicate. The results of this study show that mineral wool is a very promising raw material for alkali activation.

Characteristic Study of Shenmu Bituminous Coal Combustion with Online TG-MS-FTIR

Science.gov (United States)

Pan, Guanfu

2018-01-01

The combustion characteristics of Shenmu bituminous pulverized coal (SBC) were comprehensively investigated with a combined TG-MS-FTIR system by considering the effect of particle size, heating rate and total flowrate. The combustion products were accurately quantified by normalization and numerical analysis of MS results. The results indicate that the decrease of the particle size, heating rate and total flowrate result in lower ignition and burnout temperatures. The activation energy tends to be lower with smaller particle size, lower heating rate and total flowrate. The MS and FTIR results demonstrate that lower concentrations of different products, such as NO, NO2, HCN, CH4 and SO2 were produced with smaller particle size, slower heating rate and lower total flowrate. The decrease of particle size would lead to more contact area with oxygen and slower heating rate could provide more sufficient time for the diffusion. High total flowrate would reduce the oxygen adsorbability on the coal particle surface and shorten the residence time of oxygen, which makes the ignition difficult to occur. This work will guide to understand the combustion kinetics of pulverized coals and be beneficial to control the formation of pollutants.

A model of the enhancement of coal combustion using high intensity acoustic fields

International Nuclear Information System (INIS)

Yavuzkurt, S.; Ha, M.Y.; Koopmann, G.H.; Scaroni, A.

1989-01-01

In this paper a model for the enhancement of coal combustion in the presence of high intensity acoustics is developed. A high intensity acoustic field induces an oscillating velocity over pulverized coal particles otherwise entrained in the main gas stream, resulting in increased heat and mass transfer. The augmented heat and mass transfer coefficients, expressed as space- and time-averaged Nusselt and Sherwood numbers for the oscillating flow, were implemented in an existing computer code (PCGC-2) capable of predicting various aspects of pulverized coal combustion and gasification. Increases in the Nusselt and Sherwood numbers of about 45, 60 and 82.5% at sound pressure levels of 160, 165, and 170 dB for 100 μm coal particles were obtained due to increases in the acoustic slop velocity associated with the increased sound pressure levels. The main effect of the acoustic field was observed during the char combustion phase in a diffusionally controlled situation. A decrease in the char burnout length (time) of 15.7% at 160 dB and 30.2% at 170 dB was obtained compared to the case with no sound for the 100 μm coal particles

DESIGNING AND OPPORTUNITY FUEL WITH BIOMASS AND TIRE-DERIVED FUEL FOR COFIRING AT WILLOW ISLAND GENERATING STATION AND COFIRING SAWDUST WITH COAL AT ALBRIGHT GENERATING STATION

Energy Technology Data Exchange (ETDEWEB)

K. Payette; D. Tillman

2004-06-01

During the period July 1, 2000-March 31, 2004, Allegheny Energy Supply Co., LLC (Allegheny) conducted an extensive demonstration of woody biomass cofiring at its Willow Island and Albright Generating Stations. This demonstration, cofunded by USDOE and Allegheny, and supported by the Biomass Interest Group (BIG) of EPRI, evaluated the impacts of sawdust cofiring in both cyclone boilers and tangentially-fired pulverized coal boilers. The cofiring in the cyclone boiler--Willow Island Generating Station Unit No.2--evaluated the impacts of sawdust alone, and sawdust blended with tire-derived fuel. The biomass was blended with the coal on its way to the combustion system. The cofiring in the pulverized coal boiler--Albright Generating Station--evaluated the impact of cofiring on emissions of oxides of nitrogen (NO{sub x}) when the sawdust was injected separately into the furnace. The demonstration of woody biomass cofiring involved design, construction, and testing at each site. The results addressed impacts associated with operational issues--capacity, efficiency, and operability--as well as formation and control of airborne emissions such as NO{sub x}, sulfur dioxide (SO{sub 2}2), opacity, and mercury. The results of this extensive program are detailed in this report.

Study of the O2/CO2 combustion technology; Sanso nensho gijutsu ni kakawaru chosa kenkyu

Energy Technology Data Exchange (ETDEWEB)

Kato, M [Center for Coal Utilization, Japan, Tokyo (Japan); Kiga, T; Yamada, T [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan); Arai, K [Nippon Sanso K.K., Tokyo (Japan); Mori, T [Inst. of Research and Innovation, Tokyo (Japan); Kimura, N; Okawa, M [Electric Power Development Co. Ltd., Tokyo (Japan)

1996-09-01

This study is being progressed during a period from 1992 to 1999 as part of the NEDO`s clean coal technology program. This paper describes what has been discussed to date. The absorption method and the adsorption method may be used to recover CO2 as means to deal with the problem of global warming resulted from burning coals. These methods, however, have problems in economy caused from concentration of CO2 in flue gas being low. The present study is intended to raise the CO2 concentration in flue gas by using oxygen plus circulated flue gas in the place of combustion air, so that CO2 may be recovered as it is without being separated from the flue gas. Therefore, an oxygen-blown pulverized coal fired power generation plant having a cryogenic oxygen manufacturing equipment was designed to discuss the plant operability and economy, and the pulverized coal combustion technology by using a dynamic simulation. A large number of findings have been obtained already, and the study has reached a level at which grasping the whole image is now possible. 13 figs.

Device for reprocessing nuclear fuels

International Nuclear Information System (INIS)

Hatano, Mamoru.

1981-01-01

Purpose: To readily discharge a nuclear fuel by burning the nuclear fuel as it is without a pulverizing step and removing the graphite and other coated fuel particles. Constitution: An oxygen supply pipe is connected to the lower portion of a discharge chamber having an inlet for the fuel, and an exhaust pipe is connected to the upper portion of the chamber. The fuel mounted on a metallic gripping member made of metallic material is inserted from the inlet, the gripping member is connected through a conductor to a voltage supply unit, oxygen is then supplied through the oxygen supply tube to the discharge chamber, the voltage supply unit is subsequently operated, and discharge takes place among the fuels. Thus, high heat is generated by the discharge, the graphite carbon of the fuel is burnt, silicon carbide is destroyed and decomposed, the isolated nuclear fuel particles are discharged from the exhaust port, and the combustion gas and small embers are exhausted from the exhaust tube. Accordingly, radioactive dusts are not so much generated as when using a mechanical pulverizing means, and prescribed objective can be achieved. (Yoshino, Y.)

Comparison of different CFD software performances in the case of an incompressible air flow through a straight conical diffuser

Directory of Open Access Journals (Sweden)

Novković Đorđe M.

2017-01-01

Full Text Available Paper gives a review of the most important results of turbulence research achieved by the Laboratory for Thermal Engineering and Energy at the Vinca Insitute of Nuclear Sciences. Paper presents detailed overview of the history of the scientific research provided in the laboratory, from the beginning in the mid-60s to today, pointing out the main reasons initiating the investigations in this field. After the first period, which was mainly devoted to the research of the structure of the turbulence, since the beginning of the 80s, research is mainly oriented to the flows at high temperatures including chemical reactions and to the development and improvement of differential mathematical models as a modern and very efficient tool in the technological development. This research significantly contributed to the development of pulverized coal burners, plasma-chemical reactors, and optimization of pulverized coal fired boilers operating parameters and prediction of the greenhouse gases emissions. Most recent period includes experimental and numerical studies of the coherent structures in turbulent fluid jets, mathematical modeling of various turbulent thermal flow processes including two-phase turbulent flow in the multiphase heat exchangers and mathematical modeling of the atmospheric boundary layer.

Advanced electrostatic precipitators. Precipitadores electrostaticos avanzados

Energy Technology Data Exchange (ETDEWEB)

Velasco Rodriguez, M [GDV Foster Wheeler, S.A., Madrid (Spain)

1992-10-01

It has to be considered that electrofilters carry out a function that is regulated by the industrial ethic to not produce effluents which are damaging to health of people or animals, and which gives industry the possibility of complying with legislation. Electrofilters have been demonstrated to be the medium most capable of cleaning dust from waste gases from the combustion of pulverized coal. 11 figs., 2 tabs.

Process to improve combustion and coalescing characteristics of coal pellets

Energy Technology Data Exchange (ETDEWEB)

Ban, T.E.; Marlowe, W.H.

1980-10-23

Baking types of coal, which occur mainly in the Midwestern States of the USA, tend to form solid layers when heated to remove tar. In order to prevent this, it is proposed to pulverize the coal, to form small pellets and to coat these pellets. A suitable coating material mentioned here is sodium carbonate. Variants of the coating process are given. The coated pellets are heated.

Fluidized bed boiler feed system

Science.gov (United States)

Jones, Brian C.

1981-01-01

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

The exergy fields in transport processes: Their calculation and use

Energy Technology Data Exchange (ETDEWEB)

Lior, N.; Sarmiento-Darkin, W.; Al-Sharqawi, H.S. [University of Penn, Philadelphia, PA (United States). Dept. of Mechanical Engineering & Applied Mechanics

2006-04-15

This paper is a brief review of the method for analyzing the space and time dependent exergy and irreversibility fields in processes. It presents the basic equations, the method for their use, major literature sources, and three examples from the authors' work: flow desiccation, combustion of oil droplets, and combustion of pulverized coal. Conclusions from this Second Law analysis are used to attempt process improvement suggestions.

Physical Properties of Biomass Fuel Briquette from Oil Palm Residues

African Journals Online (AJOL)

Palm Kernel Shell (PKS) and Mesocarp Fibre (MF) were used for the production of fuel briquettes in this study in order to supplement the energy mix of the nation. PKS was pulverized and then sieved into different grain particles of 350 μm, 250 μm and 150 μm, before mixing with MF in the ratios: 90:10, 80:20 and 70:30 ...

THE DETERMINATION OF VOLATILE COMPOSITION OF SOLID FUELS BY CHROMATOGRAPHY

OpenAIRE

BICA Marin; SOFRONIE Sorin; CERNAIANU Corina Dana

2014-01-01

The volatile materials released during the heating of solid fuels ignite at relatively low temperatures releasing heat function of their quantity and quality. This heat raises the temperature of the solid residue creating the conditions for his ignition and burning. In the case of burning of the pulverized coal the phenomenon of production, ignition and burning of volatile materials are studied in different articles.

Influence of Process Parameters on Nitrogen Oxide Formation in

DEFF Research Database (Denmark)

Lans, Robert Pieter Van Der; Glarborg, Peter; Dam-Johansen, Kim

1997-01-01

This paper describes the influence of burner operating conditions, burner geometry and fuel parameters on the formation of nitrogen oxide during combustion of pulverized coal. Main attention has been paid to combustion test facilities with self-sustaining flames, while extensions have been made...... to full scale boilers and furnace modeling. Since coal combustion and flame aerodynamics have been reviewed earlier, these phenomena are only treated briefly....

Quality control of estrogen receptor assays.

Science.gov (United States)

Godolphin, W; Jacobson, B

1980-01-01

Four types of material have been used for the quality control of routine assays of estrogen receptors in human breast tumors. Pieces of hormone-dependent Nb rat mammary tumors gave a precision about 40%. Rat uteri and rat tumors pulverized at liquid nitrogen temperature and stored as powder yielded precision about 30%. Powdered and lyophilised human tumors appear the best with precision as good as 17%.

Measurement of gas species, temperatures, char burnout, and wall heat fluxes in a 200-MW{sub e} lignite-fired boiler at different loads

Energy Technology Data Exchange (ETDEWEB)

Li, Zhengqi; Jing, Jianping; Liu, Guangkui; Chen, Zhichao; Liu, Chunlong [School of Energy Science and Engineering, Harbin Institute of Technology, 92, West Dazhi Street, Harbin 150001 (China)

2010-04-15

We measured various operational parameters of a 200-MW{sub e}, wall-fired, lignite utility boiler under different loads. The parameters measured were gas temperature, gas species concentration, char burnout, component release rates (C, H and N), furnace temperature, heat flux, and boiler efficiency. Cold air experiments of a single burner were conducted in the laboratory. A double swirl flow pulverized-coal burner has two ring recirculation zones that start in the secondary air region of the burner. With increasing secondary air flow, the air flow axial velocity increases, the maximum values for the radial velocity, tangential velocity, and turbulence intensity all increase, and there are slight increases in the air flow swirl intensity and the recirculation zone size. With increasing load gas, the temperature and CO concentration in the central region of burner decrease, while O{sub 2} concentration, NO{sub x} concentration, char burnout, and component release rates of C, H, and N increase. Pulverized-coal ignites farther into the burner, in the secondary air region. Gas temperature, O{sub 2} concentration, NO{sub x} concentration, char burnout and component release rates of C, H, and N all increase. Furthermore, CO concentration varies slightly and pulverized-coal ignites closer. In the side wall region, gas temperature, O{sub 2} concentration, and NO{sub x} concentration all increase, but CO concentration varies only slightly. In the bottom row burner region the furnace temperature and heat flux increase appreciably, but the increase become more obvious in the middle and top row burner regions and in the burnout region. Compared with a 120-MW{sub e} load, the mean NO{sub x} emission at the air preheater exits for 190-MW{sub e} load increases from 589.5 mg/m{sup 3} (O{sub 2} = 6%) to 794.6 mg/m{sup 3} (O{sub 2} = 6%), and the boiler efficiency increases from 90.73% to 92.45%. (author)

Experience of COPENE in the biomass field as alternative energy; Experiencia da COPENE no campo da biomassa como alternativa energetica

Energy Technology Data Exchange (ETDEWEB)

Lopez, B D; Nose, Junior, N; Nardi, L C [COPENE, Camacari, BA (Brazil)

1985-12-31

This paper presents the experience of COPENE (Camacari Petrochemical Complex Company) in the substitution of fuel fossil energy by biomass energy to supply the increasing steam demand in its installations. In the middle of 1981, COPENE decided to install a boiler with generating capacity of 400 ton per year. That boiler will burn pulverized wood reducing oil consumption by about 200,000 ton per year. 4 figs., 1 tab.

Advanced Technology for Pyrotechnic Mixtures and Munitions

Science.gov (United States)

1977-07-01

or at ambient I ,/ BLENDING AND CASTING CURING REMOVING MOLD WAFER MANUFACTURING ? / I / SI ,/ iAUTOMATIC LOADING Figure 1. Plastic Bonded Starter Mix...material (fines) is recycled through the compacting rollers. asshwn The Chilsonator used at EA consisted only of the compaction rollers and the controls ...standardized process controls . Oversize material is pulverized and combined with the undersize material for s" ,regranulation in another batch. 2 ,Both the

Scanima A/S - fra tilfældig til succesfuld WEB-strategi

DEFF Research Database (Denmark)

Rask, Morten

2001-01-01

Scanima A/S udvikler og producerer miksere, at der indgår i procesanlæg til blanding af vand og pulver og de anvendes primært i fødevareindustrien. Hjemmesidens formål er at styrke Scanima's internationaliseringsproces gennem at udvikle eksisterende kunderelationer og skabe nye kunderelationer. D...... bevidst har ændret sin organisering. Hvilket der nu arbejdes på. Anden generation af hjemmesiden er på vej....

Assessing coal burnout

Energy Technology Data Exchange (ETDEWEB)

Lowe, A. [Pacific Power, Sydney, NSW (Australia)

1999-11-01

Recent research has allowed a quantitative description of the basic process of burnout for pulverized coals to be made. The Cooperative Research Centre for Black Coal Utilization has built on this work to develop a coal combustion model which will allow plant engineers and coal company representatives to assess their coals for combustion performance. The paper describes the model and its validation and outlines how it is run. 2 figs.

Military Handbook. Grounding, Bonding, and Shielding for Electronic Equipments and Facilities. Volume 1. Basic Theory

Science.gov (United States)

1987-12-29

when the air or gas stream contains particulate matter. b. Pulverized materials passing through chutes or pneumatic conveyors . c. Nonconductive power...Hanover NH, 1971, AD 722 221. 146.Oakley, R.J., "Surface Transfer Impedance and Cable Shielding Design ," Wire Journal, Vol 4, No. 3, March 1971, pp...including considerations of grounding, bonding, and shielding in all phases of design , construction, operation, and maintenance of electronic equipment

Snow Roads at McMurdo Station, Antarctica

Science.gov (United States)

2010-05-01

is minimized distribution of low strength areas (also called “ holidays ”). Holidays are actually areas of pulverized snow that are missed or inade...quately processed. Though holidays usually occur sporadically, any single flaw may extend through the entire thickness of an unelevated road. The...Pegasus Road and the LDB pad. A few additional sites were chosen for comparison (Williams Field, virgin snow, etc.). Williams Field Road densities

Coal utilization technologies in the production of electric energy; Technologie wykorzystania wegla do produkcji energii elektrycznej

Energy Technology Data Exchange (ETDEWEB)

Golec, T.; Rakowski, J. [Power Institute, Warsaw (Poland)

2004-07-01

The paper presents an assessment of the various technologies for power generation from coal and discusses the development prospects for each. The technologies are: pulverized fuel fired boilers for supercritical steam parameters; atmospheric fluidized bed boilers; pressurised fluidized-bed combustion boilers; gas and steam units integrated with gasification of solid fuels; and co-firing of solid fuels. It addresses, briefly, CO{sub 2} reduction technologies. 26 refs., 3 figs., 8 tabs.

Uuenenud otsustuskogu : senat / Hille Erik

Index Scriptorium Estoniae

Erik, Hille

2005-01-01

12. septembril kogunes esimest korda TLÜ kollegiaalne otsustuskogu - senat: M. Heidmets, H. Mattisen, P. Normak, M. Lepik, M. Talsi, S. Liiv, P. Reiska, K. Port, E. Rüütel, A. Kivinukk, A. Pulver, R. Raud, E. Eisenschmidt, K. Karron, H. Šein, P. Raudkivi, A. Kollist, K. Katus, K. Loogma, R. Vetik, J.-M. Punning, M. Ehala, P. Tammela, T. Tõnise, L. Läänemets, L. Saareväli, A. King

Technologie výroby a kontrola jakosti živočišných produktů s označením zaručená tradiční specialita

OpenAIRE

Chovancová, Tereza

2015-01-01

This bachelor thesis deals with the issues concerned with the performance, production and quality control of the meat products with "Traditional specialities guaranteed" indication. The first part deals with historical development of producing and range of meat products in the Czech Republic, the range of meat products according to the ordinance 326/2001 Sb. as amended. Moreover, the basic methods of meat products manufacturing are described (resources, pulverization, mixing, stuffing, formin...

Combustion of pulverized fuel under oxycoal conditions at low oxygen concentrations

Energy Technology Data Exchange (ETDEWEB)

Toporov D.; Foerster M.; Kneer R. [RWTH Aachen University, Aachen (Germany). Institute of Heat and Mass Transfer

2007-07-01

Oxycoal combustion followed by post-combustion CO{sub 2} sequestration has gained justified interest as an option for significant and relatively quick reduction of emissions from fossil fuel power generation, while taking advantage of the existing power plant infrastructure. Burning pulverised coal in a mixture of CO{sub 2}/O{sub 2} instead of air, however, will lead to modified distributions of temperature, species, and radiation fluxes inside the combustion chamber causing a retroaction on the homogeneous and heterogeneous reactions. Utilizing a burner design, which was optimised for coal combustion in air, for oxycoal combustion will lead to flame instability and poor burnout. Stabilisation of the combustion process can be obtained by: i) an increased oxygen concentration (more than 21% vol.) in the oxidiser mixture, thus achieving similar reaction rates and temperature levels to a pulverised fuel-air flame without significant changes to the flame aerodynamics. ii) modifications to the burner aerodynamics, as presented here. The results in this study are obtained in the frame of OXYCOAL-AC, the research project, having the aim to burn a pulverised coal in a CO{sub 2}/O{sub 2}-atmosphere with oxygen, produced from high-temperature ceramic membrane thus leading to higher efficiency of the whole oxycoal process. Numerical and experimental investigations of a stable oxycoal flame, obtained with {le} 21% oxygen concentration in the burning mixture at the RWTH test facility are reported. Two different burner designs are considered, conclusions concerning the achievement of a stable oxycoal flame at O{sub 2} volume concentrations equal and less to the one of oxygen in air are derived. 8 refs., 7 figs., 1 tab.

High filler concrete using pulverized fuel ash: Chloride penetration and microstructure

NARCIS (Netherlands)

Valcke, S.L.A.; Polder, R.B.; Nijland, T.G.; Leegwater, G.A.; Visser, J.H.M.; Bigaj-Van Vliet, A.A.J.

2010-01-01

The strength of concrete is linked to the amount of cement used. In many applications, concrete has a considerably higher strength than designed and structurally required. Lowering cement contents, thus reducing strength, significantly reduces the ecological impact of any concrete in terms of raw

The Technology of Nitrogen Oxide Emissions Reduction at Pulverized Coal Burning

Directory of Open Access Journals (Sweden)

Dunaevska, N.I.

2016-11-01

Full Text Available To assess the effectiveness of the influence of thermochemical preparation of anthracite on the formation of nitrogen oxides the three-dimensional numerical model of the TPP-210A boiler`s furnace for standard and modified burners was created. The calculation results are shown the decrease of NOx concentration across the height of the furnace and reduce of the unburnt coal for the modified burners in comparison with standard ones.

Water permeabilities of pulverized fuel ash; Bifuntan sekitanbai no tosui tokusei

Energy Technology Data Exchange (ETDEWEB)

Ichikawa, T [Center for Coal Utilization, Japan, Tokyo (Japan); Nagataki, S [Niigata University, Niigata (Japan); Hosoda, N [Kumagai Gumi Co. Ltd., Tokyo (Japan); Utsuki, T [The Coal Mining Research Center, Japan, Tokyo (Japan); Kubo, H [Obayashi Corp., Tokyo (Japan)

1996-09-01

It is intended to establish a technology to utilize coal ash in bulk to deal with its increasing production. In order to expand its use into earth engineering materials, two kinds of combustion ashes produced from dust coal burning power plants were used for studies using different kinds of tests. The tests were carried out on strength properties, water permeability, and characteristics of dissolving trace amounts of chemical constituents, with regard to addition effects of cement into compacted and slurry-state dust coal burned ashes. The derived findings may be summarized as follows: as the strength properties, the strength for both of the compacted and slurry-state ashes increases as the cement addition ratio is increased; growth of the strength due to the cement addition ratio and material age varies depending on the kinds of dust coal burned ash; comparison of strengths of the compacted and the slurry-state ashes indicates the strength of the latter ash is about one-third to quarter of that of the former ash; water permeability of the ashes decreases both in the compacted and slurry- state ashes as the cement addition ratio is increased; and the cement addition ratio gives greater impact to the water permeability than the density of the ashes. 28 figs., 5 tabs.

Panevezhys ja Rakvere saavad sõbraks / Vitas Matuzas ; interv. Andres Pulver

Index Scriptorium Estoniae

Matuzas, Vitas

2005-01-01

Panevezhyse linnapea sõnul on Rakverel ja Panevezhysel palju ühist ning linnadevaheline koostöö väga oluline. 15. juunil kirjutatakse alla Rakvere ja Panevezhyse sõpruslepingule. Lisa: Panevezhys

Pulverization of boron element and proportions of boron carbide in boron

International Nuclear Information System (INIS)

Lang, F.M.; Finck, C.

1956-01-01

It is possible to reduce boron element into fine powder by means of a mortar and pestle made of sintered boron carbide, the ratio of boron carbide introduced being less than one per cent. Boron element at our disposal is made of sharp edged, dark brown, little grains of average size greater than 5 μ. Grain sizes smaller than 1μ are required for applying thin layers of such boron. (author) [fr

Pyrite thermochemistry, ash agglomeration, and char fragmentation during pulverized coal combustion

Energy Technology Data Exchange (ETDEWEB)

Akan-Etuk, A.; Diaz, R.; Niksa, S.

1991-10-01

The objective of the present work is to introduce an experimental program that will eventually lead to time-resolved iron ash composition over the technological operating domain. The preceding literature survey suggests two important stipulations on any such experimental program. The first stipulation is that good control must be established over the operating conditions, to accurately quantify their effects. The other is that data must be obtained rapidly, to thoroughly cover the important operating domain. This work presents a series of studies that has characterized the desulfurization of pyrite during the early stages of combustion. An experimental system was established and used to monitor the effects of oxygen, temperature, and residence time on the evolution of condensed phase products of the combustion of pure pyrite. (VC)

Assessment of ecotoxicological risks of element leaching from pulverized coal ashes

NARCIS (Netherlands)

Jenner, H.A.

1995-01-01

This thesis describes the consequences of the disposal of the combustion residues of coal, especially the uptake of elements from such residues and their effects on various organisms. The effects on benthic organisms in fresh and in seawater are considered in the first two parts. The third

Canadian trace emissions project management : phase 2

International Nuclear Information System (INIS)

Lajeunesse, J.J.G.

1997-12-01

A comprehensive emission study was carried out at Nova Scotia Power's Lingan generating station in which pulverized coal, bottom ash, bottom ash cooling water, fly ash and flue gas were sampled and analyzed for organic and inorganic priority substances. The sampling was done according to the recommended standard of sampling provided by the Canadian Electricity Association's 1992 report entitled 'Trace Emission Project Management : phase 1'. The objectives of this emission study were to show how priority substances are transformed and partitioned within the various process streams in a modern pulverized coal-fired utility boiler and to determine the type and emission rate of various priority substances in the flue gas. An emission data set was prepared in PISCES format, and the data was used to evaluate the effectiveness of the electrostatic precipitator for controlling the emissions of these priority substances. All but five of the elements tracked in the report had mass balances from 90 per cent to 112 per cent. The five elements for which such closure could not be achieved were zinc, mercury, selenium, chlorine and bromine.The data set produced was used to evaluate the Ontario Hydro 640 MJ/h pilot scale combustor and FACT mathematical models. 39 refs., 32 tabs., 10 figs., 2 appendices

Pyrosequencing Analysis of Cryogenically Ground Samples from Primary and Secondary/Persistent Endodontic Infections.

Science.gov (United States)

Keskin, Cangül; Demiryürek, Ebru Özsezer; Onuk, Ertan Emek

2017-08-01

This study aimed to characterize the microbial communities of primary and secondary/persistent endodontic infections using high-throughput pyrosequencing from the pulverized samples. The roots of 20 extracted human teeth with primary endodontic infection and 20 teeth with secondary/persistent endodontic infection were collected. The outer surfaces of the roots were disinfected, and whole roots were cryopulverized. 16S amplicon pyrosequencing data from the DNA extracted from the pulverized root powders were obtained, and microorganism abundance and diversity were calculated. Data were analyzed using statistical and bioinformatic methods. Pyrosequencing analysis resulted a total of 2,606,128 sequences from 40 samples. A total of 15 phyla, 160 genera, and 368 species were detected. No significant difference between primary and secondary/persistent endodontic infections was found regarding the diversity and richness of operational taxonomic units at the phyla, genera, and species levels (P > .005). The present study revealed that the microbial diversity of secondary/persistent endodontic infections did not differ than those of primary endodontic infections. A new archaeal species, Candidatus Nitrosoarchaeum limnia, was detected in root canals of 1 patient with primary endodontic infection for the first time. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Inorganic Glue Enabling High Performance of Silicon Particles as Lithium Ion Battery Anode

KAUST Repository

Cui, Li-Feng

2011-01-01

Silicon, as an alloy-type anode material, has recently attracted lots of attention because of its highest known Li+ storage capacity (4200 mAh/g). But lithium insertion into and extraction from silicon are accompanied by a huge volume change, up to 300, which induces a strong strain on silicon and causes pulverization and rapid capacity fading due to the loss of the electrical contact between part of silicon and current collector. Silicon nanostructures such as nanowires and nanotubes can overcome the pulverization problem, however these nano-engineered silicon anodes usually involve very expensive processes and have difficulty being applied in commercial lithium ion batteries. In this study, we report a novel method using amorphous silicon as inorganic glue replacing conventional polymer binder. This inorganic glue method can solve the loss of contact issue in conventional silicon particle anode and enables successful cycling of various sizes of silicon particles, both nano-particles and micron particles. With a limited capacity of 800 mAh/g, relatively large silicon micron-particles can be stably cycled over 200 cycles. The very cheap production of these silicon particle anodes makes our method promising and competitive in lithium ion battery industry. © 2011 The Electrochemical Society.

Temporal and spatial variations in fly ash quality

Science.gov (United States)

Hower, J.C.; Trimble, A.S.; Eble, C.F.

2001-01-01

Fly ash quality, both as the amount of petrographically distinguishable carbons and in chemistry, varies in both time and space. Temporal variations are a function of a number of variables. Variables can include variations in the coal blend organic petrography, mineralogy, and chemistry; variations in the pulverization of the coal, both as a function of the coal's Hardgrove grindability index and as a function of the maintenance and settings of the pulverizers; and variations in the operating conditions of the boiler, including changes in the pollution control system. Spatial variation, as an instantaneous measure of fly ash characteristics, should not involve changes in the first two sets of variables listed above. Spatial variations are a function of the gas flow within the boiler and ducts, certain flow conditions leading to a tendency for segregation of the less-dense carbons in one portion of the gas stream. Caution must be applied in sampling fly ash. Samples from a single bin, or series of bins, m ay not be representative of the whole fly ash, providing a biased view of the nature of the material. Further, it is generally not possible to be certain about variation until the analysis of the ash is complete. ?? 2001 Elsevier Science B.V. All rights reserved.

Coal combustion aerothermochemistry research. Final report

Energy Technology Data Exchange (ETDEWEB)

Witte, A.B.; Gat, N.; Denison, M.R.; Cohen, L.M.

1980-12-15

On the basis of extensive aerothermochemistry analyses, laboratory investigations, and combustor tests, significant headway has been made toward improving the understanding of combustion phenomena and scaling of high swirl pulverized coal combustors. A special attempt has been made to address the gap between scientific data available on combustion and hardware design and scaling needs. Both experimental and theoretical investigations were conducted to improve the predictive capability of combustor scaling laws. The scaling laws derived apply to volume and wall burning of pulverized coal in a slagging high-swirl combustor. They incorporate the findings of this investigation as follows: laser pyrolysis of coal at 10/sup 6/ K/sec and 2500K; effect of coal particle shape on aerodynamic drag and combustion; effect of swirl on heat transfer; coal burnout and slag capture for 20 MW/sub T/ combustor tests for fine and coarse coals; burning particle trajectories and slag capture; particle size and aerodynamic size; volatilization extent and burnout fraction; and preheat level. As a result of this work, the following has been gained: an increased understanding of basic burning mechanisms in high-swirl combustors and an improved model for predicting combustor performance which is intended to impact hardware design and scaling in the near term.

Simulation for the powder movement and accumulation in the lower part of blast furnace

Energy Technology Data Exchange (ETDEWEB)

Sugiyama, Takashi [Mineral Resources Research Center, Nippon Steel Technoresearch, Futtsu-shi Chiba (Japan)

1998-12-31

The behavior of unburnt char and coke powder in the blast furnace becomes material for discussion with the increase in injection rate of pulverized coal into the blast furnace. An analysis was made as to the simulation of powder accumulation at the deadman and dripping zone of blast furnace by using a powder/gas two-phases flow experimental data. When an excessive powder has penetrated at a low gas velocity, it brings an increment in holdup and the controlling factors are powder/gas ratio and gas velocity. An empirical formula used for estimating the powder hold-up in the blast furnace internal conditions has proposed based on similarity. The controlling {pi} numbers are Floude number, powder/gas ratio and particle diameter ratio of powder/lump. This empirical formular was connected with Blast Furnace Total Model `BRIGHT` for the simulation of powder amount distribution in the lower part of blast furnace. When Powder diameter Dk exceeds 100 {mu} and gas velocity becomes lower than 0.7m/s at PC1OOkg/T, the powder tends to accumulate in the deadman. These results was available for the decision of optimum blast conditions and optimum powder diameter in the high amount of pulverized coal injection to the blast furnace. (author) 10 refs.

Feasibility study on energy conservation and environmental improvement at Pakistan Steel

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

Feasibility study on energy conservation and environmental improvement was carried out with the aim of considering the realization of the CDM (clean development mechanism) project for reduction of global warming gas emissions and contributing to the environmental improvement and economic growth in Pakistan. In the study, projects on the following were studied: coke oven coal moisture control (CMC), sinter cooler waste heat recovery, blast furnace hot stove waste heat recovery, blast furnace pulverized coal injection (PCI), blast furnace top pressure recovery turbine (TRT), hot strip mill reheating furnace regenerative type burner, coke oven environmental improvement, and blast furnace cast house dust collection. As a result of the study, the implementation of the following three projects was regarded as promising in terms of energy conservation and economical effects: blast furnace pulverized coal injection, blast furnace top pressure recovery turbine and hot strip mill reheating furnace regenerative type burner. Further, the reduction in poisonous gas by the coke oven environmental improvement project was made a top priority. In Pakistan, the price of energy is kept low, and therefore, effects of energy conservation projects are not very much expected. However, the PCI project has an effect of substitution of low-priced domestic coal for imported coal. (NEDO)

Investigation of air gasification of micronized coal, mechanically activated using the plasma control of the process

Directory of Open Access Journals (Sweden)

Butakov Evgenii

2017-01-01

Full Text Available Combination of the processes of coal combustion and gasification into a single technology of mechano-chemical and plasma-chemical activation is of a considerable scientific and technological interest. Enhancement of coal reactivity at their grinding with mechanical activation is associated with an increase in the reaction rate of carbon material, and at plasma-chemical effect, the main is an increase in reactivity of the oxidizing agent caused by the high plasma temperatures of atomic oxygen. The process of gasification was studied on the 1-MW setup with tangential scroll supply of pulverized coal-air mixture and cylindrical reaction chamber. Coal ground by the standard boiler mill is fed to the disintegrator, then, it is sent to the scroll inlet of the burner-reactor with the transport air. Pulverized coal is ignited by the plasmatron of 10-kW power. In experiments on air gasification of micronized coal, carried out at the temperature in the reaction chamber of 1000-1200°C and air excess α = 0.3-1, the data on CO concentration of 11% and H2 concentration of up to 6% were obtained. Air and air-steam gasification of mechanically-activated micronized coals with plasma control was calculated using SigmaFlow software package.

Investigation of air gasification of micronized coal, mechanically activated using the plasma control of the process

Science.gov (United States)

Butakov, Evgenii; Burdukov, Anatoly; Chernetskiy, Mikhail; Kuznetsov, Victor

2017-10-01

Combination of the processes of coal combustion and gasification into a single technology of mechano-chemical and plasma-chemical activation is of a considerable scientific and technological interest. Enhancement of coal reactivity at their grinding with mechanical activation is associated with an increase in the reaction rate of carbon material, and at plasma-chemical effect, the main is an increase in reactivity of the oxidizing agent caused by the high plasma temperatures of atomic oxygen. The process of gasification was studied on the 1-MW setup with tangential scroll supply of pulverized coal-air mixture and cylindrical reaction chamber. Coal ground by the standard boiler mill is fed to the disintegrator, then, it is sent to the scroll inlet of the burner-reactor with the transport air. Pulverized coal is ignited by the plasmatron of 10-kW power. In experiments on air gasification of micronized coal, carried out at the temperature in the reaction chamber of 1000-1200°C and air excess α = 0.3-1, the data on CO concentration of 11% and H2 concentration of up to 6% were obtained. Air and air-steam gasification of mechanically-activated micronized coals with plasma control was calculated using SigmaFlow software package.

Characteristic of oil palm residue for energy conversion system

International Nuclear Information System (INIS)

Muharnif; Zainal, Z.A.

2006-01-01

Malaysia is the major producer of palm oil in the world. It produces 8.5 tones per year (8.5 x 10 6 ty -1 ) of palm oil from 38.6 x 10 6 ty - 1 of fresh fruit bunches. Palm oil production generates large amounts of process residue such as fiber (5.4 x 10 6 ty - 1 ), shell (2.3 x 10 6 ty - 1 ), and empty fruit bunches (8.8 x 10 6 ty - 1 ). A large fraction of the fiber and much of the shell are used as fuel to generate process steam and electricity. The appropriate energy conversion system depends on the characteristic of the oil palm residue. In this paper, a description of characteristic of the oil palm residue is presented. The types of the energy conversion system presented are stoker type combustor and gasified. The paper focuses on the pulverized biomass material and the use of fluidized bed gasified. In the fluidized bed gasified, the palm shell and fiber has to be pulverized before feeding into gasified. For downdraft gasified and furnace, the palm shell and fiber can be used directly into the reactor for energy conversion. The heating value, burning characteristic, ash and moisture content of the oil palm residue are other parameters of the study

Improving combustion characteristics and NO(x) emissions of a down-fired 350 MW(e) utility boiler with multiple injection and multiple staging.

Science.gov (United States)

Kuang, Min; Li, Zhengqi; Xu, Shantian; Zhu, Qunyi

2011-04-15

Within a Mitsui Babcock Energy Limited down-fired pulverized-coal 350 MW(e) utility boiler, in situ experiments were performed, with measurements taken of gas temperatures in the burner and near the right-wall regions, and of gas concentrations (O(2) and NO) from the near-wall region. Large combustion differences between zones near the front and rear walls and particularly high NO(x) emissions were found in the boiler. With focus on minimizing these problems, a new technology based on multiple-injection and multiple-staging has been developed. Combustion improvements and NO(x) reductions were validated by investigating three aspects. First, numerical simulations of the pulverized-coal combustion process and NO(x) emissions were compared in both the original and new technologies. Good agreement was found between simulations and in situ measurements with the original technology. Second, with the new technology, gas temperature and concentration distributions were found to be symmetric near the front and rear walls. A relatively low-temperature and high-oxygen-concentration zone formed in the near-wall region that helps mitigate slagging in the lower furnace. Third, NO(x) emissions were found to have decreased by as much as 50%, yielding a slight decrease in the levels of unburnt carbon in the fly ash.

Impact of co-combustion of petroleum coke and coal on fly ash quality: Case study of a Western Kentucky power plant

International Nuclear Information System (INIS)

Hower, James C.; Thomas, Gerald A.; Mardon, Sarah M.; Trimble, Alan S.

2005-01-01

Petroleum coke has been used as a supplement or replacement for coal in pulverized-fuel combustion. At a 444-MW western Kentucky power station, the combustion of nearly 60% petroleum coke with moderate- to high-sulfur Illinois Basin coal produces fly ash with nearly 50% uncombusted petroleum coke and large amounts of V and Ni when compared to fly ash from strictly pulverized coal burns. Partitioning of the V and Ni, known from other studies to be concentrated in petroleum coke, was noted. However, the distribution of V and Ni does not directly correspond to the amount of uncombusted petroleum coke in the fly ash. Vanadium and Ni are preferentially associated with the finer, higher surface area fly ash fractions captured at lower flue gas temperatures. The presence of uncombusted petroleum coke in the fly ash doubles the amount of ash to be disposed, makes the fly ash unmarketable because of the high C content, and would lead to higher than typical (compared to other fly ashes in the region) concentrations of V and Ni in the fly ash even if the petroleum coke C could be beneficiated from the fly ash. Further studies of co-combustion ashes are necessary in order to understand their behavior in disposal

Simulation for the powder movement and accumulation in the lower part of blast furnace

Energy Technology Data Exchange (ETDEWEB)

Sugiyama, Takashi [Mineral Resources Research Center, Nippon Steel Technoresearch, Futtsu-shi Chiba (Japan)

1997-12-31

The behavior of unburnt char and coke powder in the blast furnace becomes material for discussion with the increase in injection rate of pulverized coal into the blast furnace. An analysis was made as to the simulation of powder accumulation at the deadman and dripping zone of blast furnace by using a powder/gas two-phases flow experimental data. When an excessive powder has penetrated at a low gas velocity, it brings an increment in holdup and the controlling factors are powder/gas ratio and gas velocity. An empirical formula used for estimating the powder hold-up in the blast furnace internal conditions has proposed based on similarity. The controlling {pi} numbers are Floude number, powder/gas ratio and particle diameter ratio of powder/lump. This empirical formular was connected with Blast Furnace Total Model `BRIGHT` for the simulation of powder amount distribution in the lower part of blast furnace. When Powder diameter Dk exceeds 100 {mu} and gas velocity becomes lower than 0.7m/s at PC1OOkg/T, the powder tends to accumulate in the deadman. These results was available for the decision of optimum blast conditions and optimum powder diameter in the high amount of pulverized coal injection to the blast furnace. (author) 10 refs.

Achievement report for fiscal 2000 on development of technology related to new recycled products. Research and development of simultaneous recovery of chlorine contained in waste plastics and alkali contained in waste glass bottles; 2000 nendo shinki recycle seihin nado kanren gijutsu kaihatsu seika hokokusho. Hai plastic gan'yu enso to hai glass bin gan'yu alkali no doji kaishu ni kakawaru kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

Researches have been made on a technology to have alkali contained in waste glass bottles reacted with chlorine contained in waste plastics to separate and remove salt, and reuse the residues as a resource for cement raw material. This paper summarizes the achievements in fiscal 2000. In the research, glass powder pulverized to 5 to 10 {mu} m, calcium carbonate, iron oxide, and alumina were used to prepare raw material for the ordinary Portland cement. Vinyl chloride pulverized to 3 mm was added into this cement raw material so that chlorine-alkali equivalent ration will be 1.0, and the material was sintered in a rotary kiln at 800 to 1,400 degrees C. As a result, it was discovered that salt is produced from the alkali in glass and the chlorine in vinyl chloride, whereas the produced salt volatilizes when heated to 1,200 degrees C or higher, and clinker containing low chlorine and alkali can be produced. The test result reveals that the control range of the chlorine and alkali ratio is from 1.0 to 1.1. The remaining problems are measures against carbon monoxide and dioxin contained in the exhaust gas, and treatment of dust containing salt. (NEDO)

Development of drying and pelletizing system for concentrated waste

International Nuclear Information System (INIS)

Horiuchi, Susumu; Saito, Toru; Hirano, Mikio; Kikuchi, Makoto; Takamura, Yoshiyuki.

1980-01-01

Volume reduction is strongly required for the radioactive liquid waste generated in nuclear power plants because its storing space has increased with the operating years of the plants, though it has temporarily been stored in drum cans within the plant sites after concentrated by evaporation. The drying and pelletizing system developed by Hitachi, Ltd. in cooperation with Tokyo Electric Power Co. aims at the final disposal by solidifying stored waste after drying, pulverizing, and pelletizing concentrated liquid waste, and storing it in tanks to reduce its radioactivity for the predetermined period. The outstanding features of the system are to be capable of realizing drastic volume reduction and of storing waste as the stable solid in the form flexibly adaptable to any disposing method. The system, to which the new concepts of pulverizing by drying and pelletizing concentrated liquid waste were applied, has been subjected to various fundamental tests and the demonstration tests in a pilot plant during the research and development for 7-years, consequently it was confirmed that the system can be used practically, and the data for designing the equipment for practical use were collected. The items to be considered in designing the equipment for practical use are also mentioned. (Wakatsuki, Y.)

Fiscal 2000 achievement report on the venture business assisting type regional consortium - Minor business creation base type. Development of practical application of integrated solid waste recycling technique using highly developed equipment for waste water; 2000 nendo chiiki consortium kenkyu kaihatsu jigyo seika hokokusho. Kokinoka kaishu mizushori system wo mochiita saishigen shori gijutsu no jitsuyoka ni kansuru kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

The project aims to dry and pulverize into PDS (pulverized dry sludge) the waste (concrete sludge) discharged from ready-mixed concrete plants, and to develop its practical application. The fine sand component contained in the waste water after washing is removed to the maximum extent, and high-quality sludge-based PDS suitable for reuse is recovered. The process comprises an aggregate recovery stage, fine sand removing stage, coagulation/sedimentation stage, dewatering stage, crushing stage, drying stage, and a collection stage. High-quality PDS contains 30-40 mass% of CaO and 10-20 mass% of SiO{sub 2}, and its particles have an average diameter of 3-20{mu}m and an average specific surface area of 5,000-30,000cm{sup 2}/g. A particle is roundish with its angles rounded off. As for the fine sand component, not less than 90% thereof is removed by a wet cyclone method, and the water is collected and supplied for PDS manufacture. The development is already complete of powder and liquid coagulants, of which not less than 96% is inorganic, as coagulants exclusively for use for concrete. The quality of the manufactured PDS fulfills the target values, and it is concluded that PDS is recyclable like blast furnace slag or fly ash. (NEDO)

The ''reference costs'' of the electrical production

International Nuclear Information System (INIS)

1997-05-01

This study objective is to give an aid for the investments choice in the field of electricity production and for national choices in the field of long-dated production. Important evolutions appeared since the last exercise ''reference costs'' of 1993. Electricity production costs, presented in this study, are actualized economic costs. They consider the following production facilities: nuclear, pulverized coal with fumes processing, circulating fluidized bed, combustion turbines, cogeneration and wind turbines. (A.L.B.)

Preventing Control Constraint Violations by Use of Energy Balances for a Class of Coupled Systems: Applied to a Power Plant

DEFF Research Database (Denmark)

Odgaard, Peter Fogh; Stoustrup, Jakob

2007-01-01

recomputes the reference values to the system such that control signal constraint violations are avoided. The new reference values are found using an energy balance of the system. The scheme is intended to handle rarely occurring constraint violations, so the only concern is that the system should be stable...... and not to optimize performance during all conditions. The scheme is applied to an example with a coal mill pulverizing coal for a power plant.  ...

Gas manufacture, materials for

Energy Technology Data Exchange (ETDEWEB)

Evans, F J

1867-01-11

Cannel coal, parrot coal, shale, or the like is reduced to a fine powder and mixed with finely-divided bituminous coal, or the two coals are reduced to powder together, or pulverized bituminous coal is mixed with resin, resin oil, or coal tar. The mixture is charged into the retorts. The mixture containing resin and etc. may be first heated to cause the ingredients to cohere, and then compressed into blocks for transport.

Developing a Tactical Environment Cyber Operations Training Program

Science.gov (United States)

2015-01-31

pulverized and mixed with hot air and placed into the firebox of the boiler . Purified water is pumped through pipes inside the boiler which turns to steam...cooled by water that is pumped through tubes in the condenser. The process converts the steam back into water so that it can be recirculated and used...manipulating SCADA systems in the electrical sector (e.g., opening circuit breakers, changing tap settings, and equipment failure indication). Engineering

High Strain Rate Testing of Rocks using a Split-Hopkinson-Pressure Bar

Science.gov (United States)

Zwiessler, Ruprecht; Kenkmann, Thomas; Poelchau, Michael; Nau, Siegfried; Hess, Sebastian

2016-04-01

Dynamic mechanical testing of rocks is important to define the onset of rate dependency of brittle failure. The strain rate dependency occurs through the propagation velocity limit (Rayleigh wave speed) of cracks and their reduced ability to coalesce, which, in turn, significantly increases the strength of the rock. We use a newly developed pressurized air driven Split-Hopkinson-Pressure Bar (SHPB), that is specifically designed for the investigation of high strain rate testing of rocks, consisting of several 10 to 50 cm long strikers and bar components of 50 mm in diameter and 2.5 meters in length each. The whole set up, composed of striker, incident- and transmission bar is available in aluminum, titanium and maraging steel to minimize the acoustic impedance contrast, determined by the change of density and speed of sound, to the specific rock of investigation. Dynamic mechanical parameters are obtained in compression as well as in spallation configuration, covering a wide spectrum from intermediate to high strain rates (100-103 s-1). In SHPB experiments [1] one-dimensional longitudinal compressive pulses of diverse shapes and lengths - formed with pulse shapers - are used to generate a variety of loading histories under 1D states of stress in cylindrical rock samples, in order to measure the respective stress-strain response at specific strain rates. Subsequent microstructural analysis of the deformed samples is aimed at quantification fracture orientation, fracture pattern, fracture density, and fracture surface properties as a function of the loading rate. Linking mechanical and microstructural data to natural dynamic deformation processes has relevance for the understanding of earthquakes, landslides, impacts, and has several rock engineering applications. For instance, experiments on dynamic fragmentation help to unravel super-shear rupture events that pervasively pulverize rocks up to several hundred meters from the fault core [2, 3, 4]. The dynamic, strain

Advanced combustor design concept to control NOx and air toxics

Energy Technology Data Exchange (ETDEWEB)

Eddings, E.G.; Pershing, D.W.; Molina, A.; Sarofim, A.F.; Spinti, J.P.; Veranth, J.

1999-03-29

Direct coal combustion needs to be a primary energy source for the electric utility industry and for heavy manufacturing during the next several decades because of the availability and economic advantage of coal relative to other fuels and because of the time required to produce major market penetration in the energy field. However, the major obstacle to coal utilization is a set of ever-tightening environmental regulations at both the federal and local level. It is, therefore, critical that fundamental research be conducted to support the development of low-emission, high-efficiency pulverized coal power systems. The objective of this program was to develop fundamental understanding regarding the impact of fuel and combustion changes on NOx formation, carbon burnout and air toxic emissions from pulverized coal (pc) combustion. During pc combustion, nitrogen in the coal can be oxidized to form nitrogen oxides (NO{sub x}). The 1990 Clean Air Act Amendments established much stricter NO{sub x} emissions limits for new and existing coal-fired plants, so there has been renewed interest in the processes by which NO{sub x} forms in pc flames. One of the least understood aspects of NO{sub x} formation from pc combustion is the process by which char-N (nitrogen remaining in the char after devolatilization) forms either NO{sub x} or N{sub 2}, and the development of a fundamental understanding of this process was a major focus of this research. The overall objective of this program was to improve the ability of combustion system designers and boiler manufacturers to build high efficiency, low emission pulverized coal systems by improving the design tools available to the industry. The specific program goals were to: Use laboratory experiments and modeling to develop fundamental understanding for a new submodel for char nitrogen oxidation (a critical piece usually neglected in most NOx models.); Use existing bench scale facilities to investigate alternative schemes to

Development of UHPC Mixtures Utilizing Natural and Industrial Waste Materials as Partial Replacements of Silica Fume and Sand

OpenAIRE

Ahmad, Shamsad; Hakeem, Ibrahim; Maslehuddin, Mohammed

2014-01-01

In the exploratory study presented in this paper, an attempt was made to develop different mixtures of ultrahigh performance concrete (UHPC) using various locally available natural and industrial waste materials as partial replacements of silica fume and sand. Materials such as natural pozzolana (NP), fly ash (FA), limestone powder (LSP), cement kiln dust (CKD), and pulverized steel slag (PSS), all of which are abundantly available in Saudi Arabia at little or no cost, were employed in the de...

Beschreibung des Korngrößenwachstums bei der Wirbelschicht-Sprühgranulation mittels statistischer Modelle

OpenAIRE

Schinzinger, Oliver

2004-01-01

Ein wichtiger Schritt bei der Herstellung von Tabletten ist die Aufarbeitung eines meist sehr feinen, schlecht fließfähigen Pulvers zu einem besser fließenden Granulat. Da die Granulation aus den drei Teilprozessen Mischen, Granulieren und Trocknen besteht, werden heutzutage Granulationen in der Wirbelschicht durchgeführt. Eine Wirbelschichtapparatur vereint die drei Teilprozesse in einem Gerät. Die Wirbelschichtgranulation wird durch eine große Anzahl an Parametern beeinflusst, die in Prozes...

The development of clean coal technology is the main way to control of atmospheric pollution in China

Energy Technology Data Exchange (ETDEWEB)

Wu Lixin; Xu Hong [Clean Coal Engineering & Research Center of Coal Industry (China)

1999-11-01

Atmospheric pollution in China and its causes are analysed. Power stations, industrial boilers and kilns and domestic coal combustion are the main pollution sources. Clean coal technologies are urgently needed. Main clean coal technologies which can improve the present situation of industrial coal combustion are coal cleaning, blending and briquetting; boiler retrofitting; advanced technologies to improve combustion efficiency and reduce pollution - fluidized bed combustion and pulverized coal desulfurization; and advanced desulfurization and dedusting technologies and equipment.

Overview of current and future - clean coal technologies

International Nuclear Information System (INIS)

Darthenay, A.

1995-01-01

A new generation of advanced coal technology, environmentally cleaner and in many cases more efficient, has been developed: flue gas treatment of pulverized coal combustion, circulating fluidized bed (CFB), integrated gasification with combined cycle (IGCC) and pressurized fluidized bed combustion (PFBC). These techniques are described, giving a balance of their references and of the steps which are still to be got over in order to have industrial processes applicable to large size power plants. 4 tabs

Phytochemical Screening of Aqueous Extract of Luffa aegyptiaca (Sponge gourd) Leave Sample from Northern Nigeria: A Short Communication

OpenAIRE

Mhya DH; Mankilik, M

2014-01-01

Aqueous extract of the leaves of Luffa aegyptiaca was preliminary screened with the aim of assessing the availability of some biologically active compounds. Pulverized leaves sample of Luffa aegyptiaca was extracted with water; the filtrate was concentrated on water bath and then air-dried at 25oC. The prepared aqueous-extract was used for the phytochemical screening study which was carried out using standard methods. The phytochemicals screened from the aqueous extract of Luffa aegyptiaca sh...

Characteristics of carbonized sludge for co-combustion in pulverized coal power plants.

Science.gov (United States)

Park, Sang-Woo; Jang, Cheol-Hyeon

2011-03-01

Co-combustion of sewage sludge can destabilize its combustion profile due to high volatility, which results in unstable flame. We carried out fuel reforming for sewage sludge by way of carbonization at pyrolysis temperature of 300-500°C. Fuel characteristics of carbonized sludge at each temperature were analyzed. As carbonization temperature increased, fuel ratio increased, volatile content reduced, and atomic ratio relation of H/C and O/C was similar to that of lignite. The analysis result of FT-IR showed the decrease of aliphatic C-H bond and O-C bond in carbonization. In the analysis result of TG-DTG, the thermogravimetry reduction temperature of carbonized sludge (CS400) was proven to be higher than that of dried sludge, but lower than that of sub-bituminous coal. Hardgrove grindability index increased in proportion to fuel ratio increase, where the carbonized sludge value of 43-110 was similar or higher than the coal value of 49-63. As for ash deposits, slagging and fouling index were higher than that of coal. When carbonized sludge (CS400) and coal were co-combusted in 1-10% according to calorific value, slagging tendency was low in all conditions, and fouling tendency was medium or high according to the compositions of coal. Copyright © 2010 Elsevier Ltd. All rights reserved.

Characteristics of carbonized sludge for co-combustion in pulverized coal power plants

International Nuclear Information System (INIS)

Park, Sang-Woo; Jang, Cheol-Hyeon

2011-01-01

Co-combustion of sewage sludge can destabilize its combustion profile due to high volatility, which results in unstable flame. We carried out fuel reforming for sewage sludge by way of carbonization at pyrolysis temperature of 300-500 deg. C. Fuel characteristics of carbonized sludge at each temperature were analyzed. As carbonization temperature increased, fuel ratio increased, volatile content reduced, and atomic ratio relation of H/C and O/C was similar to that of lignite. The analysis result of FT-IR showed the decrease of aliphatic C-H bond and O-C bond in carbonization. In the analysis result of TG-DTG, the thermogravimetry reduction temperature of carbonized sludge (CS400) was proven to be higher than that of dried sludge, but lower than that of sub-bituminous coal. Hardgrove grindability index increased in proportion to fuel ratio increase, where the carbonized sludge value of 43-110 was similar or higher than the coal value of 49-63. As for ash deposits, slagging and fouling index were higher than that of coal. When carbonized sludge (CS400) and coal were co-combusted in 1-10% according to calorific value, slagging tendency was low in all conditions, and fouling tendency was medium or high according to the compositions of coal.

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

DEFF Research Database (Denmark)

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

2012-01-01

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

PROTOTYPE SCALE TESTING OF LIMB TECHNOLOGY FOR A PULVERIZED-COAL-FIRED BOILER

Science.gov (United States)

The report summarizes results of an evaluation of furnace sorbent injection (FSI) to control sulfur dioxide (SO2) emissions from coal-fired utility boilers. (NOTE: FSI of calcium-based sorbents has shown promise as a moderate SO2 removal technology.) The Electric Power Research I...

Assessing the Exergy Costs of a 332-MW Pulverized Coal-Fired Boiler

Directory of Open Access Journals (Sweden)

Victor H. Rangel-Hernandez

2016-08-01

Full Text Available In this paper, we analyze the exergy costs of a real large industrial boiler with the aim of improving efficiency. Specifically, the 350-MW front-fired, natural circulation, single reheat and balanced draft coal-fired boiler forms part of a 1050-MW conventional power plant located in Spain. We start with a diagram of the power plant, followed by a formulation of the exergy cost allocation problem to determine the exergy cost of the product of the boiler as a whole and the expenses of the individual components and energy streams. We also define a productive structure of the system. Furthermore, a proposal for including the exergy of radiation is provided in this study. Our results show that the unit exergy cost of the product of the boiler goes from 2.352 to 2.5, and that the maximum values are located in the ancillary electrical devices, such as induced-draft fans and coil heaters. Finally, radiation does not have an effect on the electricity cost, but affects at least 30% of the unit exergy cost of the boiler’s product.

FUNDAMENTAL INVESTIGATION OF FUEL TRANSFORMATIONS IN PULVERIZED COAL COMBUSTION AND GASIFICATION TECHNOLOGIES

Energy Technology Data Exchange (ETDEWEB)

Robert Hurt; Joseph Calo; Thomas H. Fletcher; Alan Sayre

2005-04-29

The goal of this project was to carry out the necessary experiments and analyses to extend current capabilities for modeling fuel transformations to the new conditions anticipated in next-generation coal-based, fuel-flexible combustion and gasification processes. This multi-organization, multi-investigator project has produced data, correlations, and submodels that extend present capabilities in pressure, temperature, and fuel type. The combined experimental and theoretical/computational results are documented in detail in Chapters 1-8 of this report, with Chapter 9 serving as a brief summary of the main conclusions. Chapters 1-3 deal with the effect of elevated pressure on devolatilization, char formation, and char properties. Chapters 4 and 5 deal with advanced combustion kinetic models needed to cover the extended ranges of pressure and temperature expected in next-generation furnaces. Chapter 6 deals with the extension of kinetic data to a variety of alternative solid fuels. Chapter 7 focuses on the kinetics of gasification (rather than combustion) at elevated pressure. Finally, Chapter 8 describes the integration, testing, and use of new fuel transformation submodels into a comprehensive CFD framework. Overall, the effects of elevated pressure, temperature, heating rate, and alternative fuel use are all complex and much more work could be further undertaken in this area. Nevertheless, the current project with its new data, correlations, and computer models provides a much improved basis for model-based design of next generation systems operating under these new conditions.

Nitrogen oxide suppression by using a new design of pulverized-coal burners

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R.; Cameron, S.D.; Grekhov, L.L. [All-Russian Thermal Engineering Institute, Moscow (Russian Federation)

1996-07-01

The results of testing a low-NO{sub x} swirl burner are presented. This burner was developed by Babcock Energy Ltd., for reducing nitrogen oxide emissions when burning Ekibastuz and Kuznetsk low-caking coals in power boilers. The tests conducted at a large plant of the BEL Technological Center showed that the new burner reduces NO{sub x} emissions by approximately two times. 6 refs., 6 figs., 1 tab.

Waste plastics as supplemental fuel in the blast furnace process: improving combustion efficiencies.

Science.gov (United States)

Kim, Dongsu; Shin, Sunghye; Sohn, Seungman; Choi, Jinshik; Ban, Bongchan

2002-10-14

The possibility of using waste plastics as a source of secondary fuel in a blast furnace has been of recent interest. The success of this process, however, will be critically dependent upon the optimization of operating systems. For instance, the supply of waste plastics must be reliable as well as economically attractive compared with conventional secondary fuels such as heavy oil, natural gas and pulverized coal. In this work, we put special importance on the improvement of the combustibility of waste plastics as a way to enhance energy efficiency in a blast furnace. As experimental variables to approach this target, the effects of plastic particle size, blast temperature, and the level of oxygen enrichment were investigated using a custom-made blast model designed to simulate a real furnace. Lastly, the combustion efficiency of the mixture of waste plastics and pulverized coal was tested. The observations made from these experiments led us to the conclusion that with the increase of both blast temperature and the level of oxygen enrichment, and with a decrease in particle size, the combustibility of waste polyethylene could be improved at a given distance from the tuyere. Also it was found that the efficiency of coal combustion decreased with the addition of plastics; however, the combustion efficiency of mixture could be comparable at a longer distance from the tuyere.

Experimental studies on the simultaneous reduction of NO and SO2 emissions by re burning

International Nuclear Information System (INIS)

Sun, Rui; Yu, Leibo; Fei, Jun; Mu, Yangyang; Zhang, Xin; Sun, Shaozeng; Wu, Shaohua

2010-01-01

The simultaneous reduction of NO and SO 2 by pulverized coal re burning was studied in a drop tube furnace (DTF). A bituminous pulverized coal was chosen as the re burning fuel, and calcium oxide was added as desulfurizer. The influences of stoichiometric ratio (SR), re burning temperature, calcium to sulfur ratio (Ca/ S), and residence time on efficiency of removing NO and SO 2 were studied by DTF hot experiments. The experiment results showed that, at the condition of the re burning temperature 1200 degree Celsius, Ca/ S=1.5, NO reduction efficiency decreased with the increase of re burning fuels stoichiometric ratio, but SO 2 reduction efficiency increased. When the re burning temperature increased from 1000 degree Celsius to 1200 degree Celsius, NO and SO 2 reduction efficiencies initially increased, but then decreased as temperature higher than 1100 degree Celsius. NO reduction efficiency decreased when Ca/ S changed from 1.0 to 2.5, and SO 2 reduction efficiency increased at all times, in spite of the increasing trend became flat when Ca/ S was higher than 2.0. Among all tests, high SO 2 and NO reduction ratios were obtained at SR of 0.8∼0.9 and Ca/ S of 1.5. The mechanisms of desulfurization and denitrification are also discussed and presented to explain the reactions routine in the DTF. (author)

Increasing coal-fired power generation efficiency to reduce electric cost and environmental emissions

International Nuclear Information System (INIS)

Torrens, I.M.; Stenzel, W.C.

1997-01-01

New generating capacity required globally between 1993 and 2010 is estimated to be around 1500 GW, of which some two-thirds will be outside the OECD, and some 40 % in the Asian non-OECD countries. Coal is likely to account for a substantial fraction of this new generation. Today's state-of-the-art supercritical coal-fired power plant has a conversion efficiency of some 42-45 %. The capital cost increase associated with the supercritical or ultra-supercritical pulverized coal power plant compared to a conventional subcritical plant is small to negligible. The increased efficiency associated with the supercritical plant leads to an actual reduction in the total cost of electricity generated in cents/kWh, relative to a conventional plant. Despite this, the power sector continues to build subcritical plants and has no near term plans to increase the efficiency of power plants in the projects it is developing. Advanced clean coal technologies such as integrated gasification combined cycle and pressurized fluidized bed combustion will be selected for independent power projects only in very specific circumstances. Advanced clean coal plants can be operated reliably and with superior performance, and specifically that their present estimated capital costs can be reduced substantially to a point where they are competitive with state-of-the-art pulverized coal technologies. (R.P.)

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

Directory of Open Access Journals (Sweden)

Wenjing Sun

2016-02-01

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

Validity of silhouette showcards as a measure of body size and obesity in a population in the African region: A practical research tool for general-purpose surveys.

Science.gov (United States)

Yepes, Maryam; Viswanathan, Barathi; Bovet, Pascal; Maurer, Jürgen

2015-01-01

The purpose of this study is to validate the Pulvers silhouette showcard as a measure of weight status in a population in the African region. This tool is particularly beneficial when scarce resources do not allow for direct anthropometric measurements due to limited survey time or lack of measurement technology in face-to-face general-purpose surveys or in mailed, online, or mobile device-based surveys. A cross-sectional study was conducted in the Republic of Seychelles with a sample of 1240 adults. We compared self-reported body sizes measured by Pulvers' silhouette showcards to four measurements of body size and adiposity: body mass index (BMI), body fat percent measured, waist circumference, and waist to height ratio. The accuracy of silhouettes as an obesity indicator was examined using sex-specific receiver operator curve (ROC) analysis and the reliability of this tool to detect socioeconomic gradients in obesity was compared to BMI-based measurements. Our study supports silhouette body size showcards as a valid and reliable survey tool to measure self-reported body size and adiposity in an African population. The mean correlation coefficients of self-reported silhouettes with measured BMI were 0.80 in men and 0.81 in women (P general-purpose surveys of obesity in social sciences, where limited resources do not allow for direct anthropometric measurements.

The effect of substitutional elements (Al, Co) in LaNi4.5M0.5 on the lattice defect formation in the initial hydrogenation and dehydrogenation

International Nuclear Information System (INIS)

Sakaki, Kouji; Akiba, Etsuo; Mizuno, Masataka; Araki, Hideki; Shirai, Yasuharu

2009-01-01

The formation of the vacancy and dislocation by the initial hydrogenation and dehydrogenation in LaNi 4.5 M 0.5 (M = Al, Co, and Ni) was observed by means of the positron lifetime technique. The concentrations of vacancy introduced by these processes were 0.25, 0.13 and 0.01 at.% for LaNi 5 , LaNi 4.5 Co 0.5 and LaNi 4.5 Al 0.5 , respectively. Al substitution into LaNi 5 significantly prevented from vacancy formation, compared with LaNi 5 and LaNi 4.5 Co 0.5 . In LaNi 4.5 Al 0.5 , the increase of the hardness and the enhancement of the pulverization, i.e. enhancement of the formation of micro cracks compared with LaNi 5 were observed while the Co substitution had little effect on pulverization and hardness as well as vacancy formation. These results show that the formation of micro cracks became more active process by Al substitution than the formation of the lattice defects to release the strain energy generated by the hydride formation because of the higher formation energy of the lattice defects in LaNi 4.5 Al 0.5 , although both the formation of micro cracks and lattice defects were still observed in all alloys we studied

Analysis of dextromethorphan and dextrorphan in decomposed skeletal tissues by microwave assisted extraction, microplate solid-phase extraction and gas chromatography- mass spectrometry (MAE-MPSPE-GCMS).

Science.gov (United States)

Fraser, Candice D; Cornthwaite, Heather M; Watterson, James H

2015-08-01

Analysis of decomposed skeletal tissues for dextromethorphan (DXM) and dextrorphan (DXT) using microwave assisted extraction (MAE), microplate solid-phase extraction (MPSPE) and gas chromatography-mass spectrometry (GC-MS) is described. Rats (n = 3) received 100 mg/kg DXM (i.p.) and were euthanized by CO2 asphyxiation roughly 20 min post-dose. Remains decomposed to skeleton outdoors and vertebral bones were recovered, cleaned, and pulverized. Pulverized bone underwent MAE using methanol as an extraction solvent in a closed microwave system, followed by MPSPE and GC-MS. Analyte stability under MAE conditions was assessed and found to be stable for at least 60 min irradiation time. The majority (>90%) of each analyte was recovered after 15 min. The MPSPE-GCMS method was fit to a quadratic response (R(2)  > 0.99), over the concentration range 10-10 000 ng⋅mL(-1) , with coefficients of variation <20% in triplicate analysis. The MPSPE-GCMS method displayed a limit of detection of 10 ng⋅mL(-1) for both analytes. Following MAE for 60 min (80 °C, 1200 W), MPSPE-GCMS analysis of vertebral bone of DXM-exposed rats detected both analytes in all samples (DXM: 0.9-1.5 µg⋅g(-1) ; DXT: 0.5-1.8 µg⋅g(-1) ). Copyright © 2014 John Wiley & Sons, Ltd.

Studies of the magnetic properties of Ni-Zn-Cu ferrite and its synthesis by using metal nitrate salts

International Nuclear Information System (INIS)

Koh, Jae Gui

2004-01-01

Ni-Zn-Cu ferrite was synthesized by decomposing the metal nitrates Ni(NO 3 ) 2 ·6H 2 O, Cu(NO 3 ) 2 ·6H 2 O, Zn(NO 3 ) 2 ·6H 2 O, and Fe(NO 3 ) 3 ·9H 2 O at 200 .deg. C for 20 hours. The ferrite powder was calcined at 400 .deg. C and pulverized for 3, 6, 9, or 12 hours in a steel ball mill. Then, it was sintered from 700 .deg. C to 1000 .deg. C in 100 .deg. C steps for 1 hour at each step. Thus, we could study the effects of the synthesis conditions on the microstructure and magnetic properties of Ni-Zn-Cu ferrite. We could chemically bond initial specimens in liquid at a low-temperature of 150 .deg. C owing to the low melting points, less than 200 .deg. C, of the metal nitrates instead of mechanical ball-mill pulverization, thus narrowing the distance between the particles a molecular one and lowering the sintering point at least by 200 .deg. C to 300 .deg. C. The initial permeability was 50 to 470, and the maximum magnetic induction and coercive force were 0.2410 T and 39.79 A/m to 95.496 A/m, respectively, which are similar to values for Ni-Zn-Cu ferrite synthesized using a conventional process.

Fluidized bed combustion bottom ash: A better and alternative geo-material resource for construction.

Science.gov (United States)

Mandal, A K; Paramkusam, Bala Ramudu; Sinha, O P

2018-04-01

Though the majority of research on fly ash has proved its worth as a construction material, the utility of bottom ash is yet questionable due to its generation during the pulverized combustion process. The bottom ash produced during the fluidized bed combustion (FBC) process is attracting more attention due to the novelty of coal combustion technology. But, to establish its suitability as construction material, it is necessary to characterize it thoroughly with respect to the geotechnical as well as mineralogical points of view. For fulfilling these objectives, the present study mainly aims at characterizing the FBC bottom ash and its comparison with pulverized coal combustion (PCC) bottom ash, collected from the same origin of coal. Suitability of FBC bottom ash as a dike filter material in contrast to PCC bottom ash in replacing traditional filter material such as sand was also studied. The suitability criteria for utilization of both bottom ash and river sand as filter material on pond ash as a base material were evaluated, and both river sand and FBC bottom ash were found to be satisfactory. The study shows that FBC bottom ash is a better geo-material than PCC bottom ash, and it could be highly recommended as an alternative suitable filter material for constructing ash dikes in place of conventional sand.

In situ stabilization of heavy metals in multiple-metal contaminated paddy soil using different steel slag-based silicon fertilizer.

Science.gov (United States)

Ning, Dongfeng; Liang, Yongchao; Song, Alin; Duan, Aiwang; Liu, Zhandong

2016-12-01

Steel slag has been widely used as amendment and silicon fertilizer to alleviate the mobility and bioavailability of heavy metals in soil. The objective of this study was to evaluate the influence of particle size, composition, and application rate of slag on metal immobilization in acidic soil, metals uptake by rice and rice growth. The results indicated that application of slag increased soil pH, plant-available silicon concentrations in soil, and decreased the bioavailability of metals compared with control treatment, whereas pulverous slag (S1) was more effective than granular slag (S2 and S3). The acid-extractable fraction of Cd in the spiked soil was significantly decreased with application of S1 at rates of 1 and 3 %, acid-extractable fractions of Cu and Zn were decreased when treated at 3 %. Use of S1 at both rates resulted in significantly lower Cd, Cu, and Zn concentrations in rice tissues than in controls by 82.6-92.9, 88.4-95.6, and 67.4-81.4 %, respectively. However, use of pulverous slag at 1 % significantly promotes rice growth, restricted rice growth when treated at 3 %. Thus, the results explained that reduced particle size and suitable application rate of slag could be beneficial to rice growth and metals stabilization.

Demonstration project: Oxy-fuel combustion at Callide-A plant

Energy Technology Data Exchange (ETDEWEB)

Makino, Keiji; Misawa, Nobuhiro; Kiga, Takashi; Spero, Chris

2007-07-01

Oxy-fuel combustion is expected to be one of the promising systems on CO2 recovery from pulverized-coal power plant, and enable the CO2 to be captured in a more cost-effective manner compared to other CO2 recover process. An Australia-Japan consortium was established in 2004 specifically for the purpose of conducting a feasibility study on the application of oxy-fuel combustion to an existing pulverized-coal power plant that is Callide-A power plant No.4 unit at 30MWe owned by CS Energy in Australia. One of the important components in this study has been the recent comparative testing of three Australian coals under both oxy-fuel and air combustion conditions using the IHI combustion test facilities. The tests have yielded a number of important outcomes including a good comparison of normal air with oxy-fuel combustion, significant reduction in NOx mass emission rates under oxy-fuel combustion. On the basis of the feasibility study, the project under Australia-Japan consortium is now under way for applying oxy-fuel combustion to an existing plant by way of demonstration. In this project, a demonstration plant of oxy-fuel combustion will be completed by the end of 2008. This project aims at recovering CO2 from an actual power plant for storage. (auth)

Popularity of processed foodstuffs for infants and small children among parents

OpenAIRE

Danuta Górecka; Barbara Szczepaniak; Krystyna Szymandera-Buszka; Ewa Flaczyk

2007-01-01

The popularity of seven groups of processed foodstuffs (soups, dinners, pulverized fruits and vegetables, desserts, dairy desserts, juices, teas) for infants and small children aged 4 months up to 3 years, available on the market and comprising a total of 154 products, was investigated in this study. A survey was carried out in the group of 100 individuals. They were mothers and fathers bringing their children to crèche as well as buying analysed products. Among 24 soups vegetable so...

Differences in carbohydrate profiles in batch culture grown planktonic and biofilm cells of Amphora rostrata Wm. Sm

Digital Repository Service at National Institute of Oceanography (India)

Khodse, V.B.; Bhosle, N.B.

material in the central equatorial Pacific. Deep-Sea Res I 43:1181-1204. Hitchcock GL. 1977. The concentration of particulate carbohydrates in a region of the West Africa upwelling zone during March 1974. Deep-Sea Res 24:83-93. Hoagland KD, Rosowski JR... and Biochemistry, IIB. Academic Press, London, pp 537-568 Roszkowski W, Beuth J, Ko HL, Uhlenbruck G, Pulverer G. 1989. Blocking of lectin like adhesion molecules on pulmonary cells inhibits lung sarcoma L colonization in BALB/c-mice. Experientia 45...

Coal Calorific Value Prediction Based on Projection Pursuit Principle

OpenAIRE

QI Minfang; FU Zhongguang; JING Yuan

2012-01-01

The calorific value of coal is an important factor for the economic operation of coal-fired power plant. However, calorific value is tremendous difference between the different coal, and even if coal is from the same mine. Restricted by the coal market, most of coal fired power plants can not burn the designed-coal by now in China. The properties of coal as received are changing so frequently that pulverized coal firing is always with the unexpected condition. Therefore, the researches on the...

Leach rate characterization of solid radioactive waste forms

International Nuclear Information System (INIS)

Flynn, K.F.; Barletta, R.E.; Jardine, L.J.; Steindler, M.J.

1978-01-01

Leach rates were measured using distilled water on four types of waste forms: spray calcined waste mixed with silica and borosilicate glass and sintered, the same pulverized, the same in a lead matrix, and waste glass containing U. Twenty isotopes ranging from 22 Na to 239 Np were measured using activation analysis. Leach rates were also measured for a variety of matrix materials (Zircaloy, Al, Pb, glass, Pb 3 RE 6 (SiO 4 ) 6 ), using one isotope each. 2 tables

Hard-rock tunneling using pulsed electron beams

International Nuclear Information System (INIS)

Avery, R.T.; Keefe, D.; Brekke, T.L.; Finnie, I.

1975-01-01

Intense sub-microsecond bursts of energetic electrons cause significant pulverization and surface spalling of a variety of rock types. The spall debris generally consists of sand, dust, and small flakes. If carried out at rapid repetition rate, this technique appears promising for increasing the speed and reducing the cost of underground excavation of tunnels, mines, and storage spaces. The conceptual design features of a pulsed electron tunnel excavator, capable of tunneling approximately ten times faster than conventional drill/blast methods, is presented. (auth)

The Environmental Assessment and Management (TEAM) Guide: Montana Supplement. Revision

Science.gov (United States)

2010-01-01

re not to b e c onfused with 1-3 Air Emissions Management conventional c ombustion de vices with e nclosed f ireboxes and c ontrolled a ir t...Added April 2002]. • Clean Lumber - wood or wood products that have been cut or shaped and include wet, air-dried, and kiln -dried wood pr oducts... conventional pulverized coal and micropulverized coal (40 CFR 60.1940) [Added April 2002]. • Modification or Modified CISWI Unit - a CISWI unit you have

Coal combustion technology in China

International Nuclear Information System (INIS)

Huang, Z.X.

1994-01-01

Coal is the most important energy source in China, the environmental pollution problem derived from coal burning is rather serious in China. The present author discusses coal burning technologies both in boilers and industrial furnaces and their relations with environmental protection problems in China. The technological situations of Circulating Fluidized Bed Coal Combustor, Pulverized Coal Combustor with Aerodynamic Flame Holder and Coal Water Slurry Combustion have been discussed here as some of the interesting problems in China only. (author). 3 refs

Radiometric determination of dilute inhomogeneous solids loading in pneumatic conveying systems

International Nuclear Information System (INIS)

Yong Yan; Byrne, Ben; Coulthard, John

1994-01-01

The application of γ-ray attenuation methods to non-intrusive measurement of the solids content in pneumatic flow lines is discussed. An instrument employing a broad single-beam interrogation geometry and a single-element detector with uniform sensitivity profile is described. It is designed primarily for metering pulverized coal, where the solids concentration is typically very low, and also often highly inhomogeneous. A detailed analysis of the factors affecting measurement accuracy is presented, together with results obtained from laboratory tests. (author)

Einsatzmöglichkeiten eines saponinreichen Extrakts aus Quillaja saponaria Molina zur Formulierung und Stabilisierung von funktionellen Lebensmittelinhaltsstoffen

OpenAIRE

Tippel, Janine

2017-01-01

Emulgatoren werden in der Lebensmittelindustrie häufig zur Herstellung disperser Trägersysteme verwendet, welche eine Solubilisierung und Erhöhung der Stabilität von lipophilen Lebensmittelinhaltsstoffen ermöglichen. Für flüssige Lebensmittelsysteme können mizellare Systeme und Emulsionen eingesetzt werden. Eine Sprühtrocknung ermöglicht hier die Umwandlung flüssiger Formulierungen in feste Pulver, welche den Transport und die Einbringung in das Endprodukt vereinfachen. Zudem können durch Ver...

Iron making technology with fuels and other materials injection in blast furnace tuyeres. Part 1. Auxiliary fuels characteristics and its influence in the blast furnace process; Tecnologia de fabricacion de arrabio con la inyeccion de combustibles y otros materiales por toberas en el horno alto. I parte. Caracteristicas de los combustibles auxiliares y su influencia en el proceso del horno alto

Energy Technology Data Exchange (ETDEWEB)

Garcia, L. [Union de Empresas de Recuperacion de Materias Primas. Ciudad de La Habana (Cuba); Cores, A.; Formoso, A. [Centro Nacional de Investigaciones Metalurgicas. Madrid (Spain); Babich, A.; Yaroshevskii, S. [Universidad Estatal Tecnologica de Donetsk. Ucrania (Ukraine)

1998-06-01

The injection of fuels by tuyeres in the blast furnace is a used practice in most furnaces with the principal aim to reduce the coke consumption by ton of pig iron produced. The nature of these fuels is very diverse and depends on the resources of each country and of the fuel price. At this moment the coal injection (pulverized and granular) is the most extended practice, and the number of furnaces with facilities for coal injection increases continuously. (Author) 14 refs.

Exploring evaluation to influence the quality of pulverized coal fly ash. Co-firing of biomass in a pulverized coal plant or mixing of biomass ashes with pulverized coal fly ash; Verkennende evaluatie kwaliteitsbeinvloeding poederkoolvliegas. Bijstoken van biomassa in een poederkoolcentrale of bijmenging van biomassa-assen met poederkoolvliegas

Energy Technology Data Exchange (ETDEWEB)

Van der Sloot, H.A.; Cnubben, P.A.J.P [ECN Schoon Fossiel, Petten (Netherlands)

2000-08-01

In this literature survey the consequences of co-firing of biomass and mixing of biomass ash with coal fly ash on the coal fly ash quality is evaluated. Biomass ash considered in this context is produced by gasification, pyrolysis or combustion in a fluidized bed. The irregular shape of biomass ash obtained from gasification, pyrolysis or combustion has a negative influence on the water demand in concrete applications of the coal fly ash resulting from mixing biomass ash and coal fly ash. In case of co-firing, high concentrations of elements capable of lowering the ash melting point (e.g., Ca and Mg) may lead to more ash agglomeration. This leads to a less favourable particle size distribution of the coal fly ash, which has a negative impact on the water demand in cement bound applications. Gasification, pyrolysis and combustion may lead to significant unburnt carbon levels (>10%). The unburnt carbon generally absorbs water and thus has a negative influence on the water demand in cement-bound applications. The contribution of biomass ash to the composition of coal fly ash will not be significantly different, whether the biomass is co-fired or whether the biomass ash is mixed off-line with coal fly ash. The limit values for Cl, SO4 and soluble salts can form a limitation for the use of coal fly ash containing biomass for cement-bound applications. As side effects of biomass co-firing, the level of constituents such as Na, K, Ca and Mg may lead to slagging and fouling of the boiler. In addition, a higher emission of flue gas contaminants As, Hg, F, Cl and Br may be anticipated in case more contaminated biomass streams are applied. This may also lead to a higher contamination level of gypsum produced from flue gas cleaning residues. Relatively clean biomass streams (clean wood, cacao shells, etc.) will hardly lead to critical levels of elements from a leaching point of view. More contaminated streams, such as sewage sludge, used and preserved wood, petcoke and RDF (refuse derived fuels), will most likely lead to increased leaching. This will be more prominent for oxyanions than for metals. In the evaluation of the application of coal fly ash in cement production or in partial cement replacement, it is important to assess the materials behaviour in recycling stages in unbound form besides its leaching behaviour of the intact product in its service life. This aspect has not been addressed before. If a material performs poorly from an environmental point of view in its recycling stages, one should be more critical in allowing (too) high levels of co-firing or too high mixing ratios of biomass. In general, the oxyanions will be more critical than most metals. The variability in several types of biomass is rather high. This holds limitations for plant operation and availability. Premixing of biomass during size reduction leads to more consistent input and thus to more constant ash quality. Co-firing may lead to increased Cr-VI levels in the fly ash due to oxidation of Cr, which is more prominently present in flue gas upon biomass co-firing than in case of regular coal firing. Elevated Cr-VI levels are more leachable. The following recommendations have been made: measurement of leaching behaviour of coal fly ash from co-firing of different biomass streams with a special emphasis on Cr-VI leachability; measurement of flue gas quality relative to pure coal combustion during co-firing of contaminated biomass streams; verification of durability of cement-based products containing coal fly ash with ash from biomass; evaluation of the leaching behaviour of recycling products from the primary uses of biomass ash or fly ash. 35 refs.

Hard rock tunneling using pulsed electron beams

International Nuclear Information System (INIS)

Avery, R.T.; Brekke, T.L.; Finnie, I.

1974-01-01

Intense submicrosecond bursts of energetic electrons cause significant pulverization and surface spalling of a variety of rock types, the spall debris generally consisting of sand, dust, and small flakes. If carried out at rapid repetition rate this can lead to a promising technique for increasing the speed and reducing the cost of underground excavation of tunnels, mines, and storage spaces. The conceptual design features of a Pulsed Electron Tunnel Excavator capable of tunneling approximately ten times faster than conventional drill/blast methods were studied. (auth)

2-22 Study of Oxidation/reduction Volatilization Technology

Institute of Scientific and Technical Information of China (English)

Tan; Cunmin[1; Cao; Shiwei[1; Tian; Yuan[1; Qin; Zhi[1

2015-01-01

As an advanced dry head-end processing of spent fuel reprocessing, the oxidation-reduction volatilization technology will use for pulverizing uranium oxide ceramic pellets, decladding, and removal of most of volatile and semi-volatile fission elements, 3H, 14C, Kr, Xe, I, Cs, Ru and Tc, from fuel prior to main treatment process. The AIROX and ORIOX process, including circulation of oxidation in oxygen atmosphere and reduction in hydrogen atmosphere, researched on international at present, is considered to be the first choice for head-end processing.

Preparation of thin layer deposits of actinides for studies in nuclear physics and solid state physics

International Nuclear Information System (INIS)

Kwinta, J.; Brossard, P.; Michel, J.J.; Thoreux, J.

1983-09-01

Two methods of deposition are described electrospraying and spraying with a ion beam. In the first method a solution is send through a capillary containing an electrode at a positive potential in respect to the support of the coating. In the second method ions (generally rare gases) produced by a source are accelerated and focussed with an electrostatic lens on the material to pulverize. Both are complementary to classical methods like electrodeposition and vacuum vaporization which are difficult to use in the case of rare isotopes [fr

Treatment of wine lees on an industrial scale. [wine lees processing

Energy Technology Data Exchange (ETDEWEB)

1978-04-24

EtOH and tartaric acid are recovered from wine lees by compressing the lees into pellets, distillation with steam to remove alcohols followed by fractional distillation to recover EtOH, roasting and pulverization of the EtOH-free pellets to coagulate collids, and extraction of the suspension with water and mineral acid to recover tartaric acid. Mother liquors are recirculated through the tartaric acid recovery process and the residual material is dried to a protein product which is useful as fertilizer or as animal feed.

Gas manufacture, materials for; distillation, destructive

Energy Technology Data Exchange (ETDEWEB)

McKenzie, G

1866-03-15

A A mixture of bituminous coal and shale oil, petroleum, or other mineral oil is distilled in a retort in order to obtain illuminating gas and oil according to the temperature, and a residue of good coke is also obtained. Preferably the coal is pulverized, and the mixture is made in a heated state. The oil may be treated for the removal of volatile oils and water before mixture with the coal. With the oil may be used the residues or bottoms from shale-oil stills.

Construction of a system for up-conversion detection in vitroceramics doped with rare earths

International Nuclear Information System (INIS)

Santa Cruz, P.A.; Azevedo, W.M. de; Sa, G.F. de

1983-01-01

A system capable of detecting up-conversion processes by energy transference or cooperative luminescence was developed. Pulverized vitroceramic samples containing PbF 2 and GeO 2 , doped with Yb 2 O 3 as sensitizer and Tm 2 O 3 or Er 2 O 3 as activator, were used. A diagram of the detection system, as well as graphs showing the variation of the emission intensity of these doped vitroceramics as a function of excitation intensity (970 mn), are presented. (C.L.B.) [pt

Reduction of NOx emission in tangential fired - furnace by changing the, mode of operation

International Nuclear Information System (INIS)

Chudnovsky, B.; Talanker, A.; Levin, L.; Kahana, S

1998-01-01

The present work analyses tile results of tests on 575 MW units with tangential firing furnace arrangement in sub-stoichiometric combustion. Tangential firing provides good conditions for implementing sub-stoichiometric combustion owing to the delivery scheme of pulverized coal and air. The furnace was tested in several different modes of operation (Over Fire Air, Bunkers Out Of Service, Excess air, Tilt etc.) to achieve low cost NOx reduction. Actual performance data are presented based on experiments made on lEC's boiler in M.D. 'B' power station

Feasibility of backfilling mines using cement kiln dust, fly ash, and cement blends

OpenAIRE

Beltagui, Hoda; Sonebi, Mohammed; Maguire, K.; Taylor, Susan

2018-01-01

Cement kiln dust (CKD) is an industrial by-product of the cement manufacturing process, the composition of which can vary widely. Recent years of using alternative fuels have resulted in higher chloride and alkali contents within CKDs; as such, this limits the applications in which CKDs can be utilised. Using a CKD containing a high free lime content of 29.5%, it is shown that this CKD is capable of activating pulverized fuel ash (PFA) due to its high alkalinity, which can be utilised in low ...

Physico-chemical, microbial and sensory properties of kunu zaki beverage sweetened with black velvet tamarind (Dialium guineense)

OpenAIRE

Abiodun, O. A.; Dauda, A. O.; Adebisi, T. T.; Alonge, C. D.

2017-01-01

This work determined the physicochemical, microbial and sensory characteristics of kunu zaki sweetened with black velvet tamarind (Dialium guinnense) flour. The outer covering and seed of black velvet was removed while the pulp was pulverized to obtain the flour. The tamarind pulp was analysed for its proximate and sugar contents. Kunu zaki was prepared according to standard method and 10, 20, 30, 40 and 50 g of the black velvet pulp was added to 1000 ml each of kunu zaki along with a control...

The advanced role of computational mechanics and visualization in science and technology: analysis of the Germanwings Flight 9525 crash

International Nuclear Information System (INIS)

Chen, Goong; Wang, Yi-Ching; Gu, Cong; Perronnet, Alain; Yao, Pengfei; Bin-Mohsin, Bandar; Hajaiej, Hichem; Scully, Marlan O

2017-01-01

Computational mathematics, physics and engineering form a major constituent of modern computational science, which now stands on an equal footing with the established branches of theoretical and experimental sciences. Computational mechanics solves problems in science and engineering based upon mathematical modeling and computing, bypassing the need for expensive and time-consuming laboratory setups and experimental measurements. Furthermore, it allows the numerical simulations of large scale systems, such as the formation of galaxies that could not be done in any earth bound laboratories. This article is written as part of the 21st Century Frontiers Series to illustrate some state-of-the-art computational science. We emphasize how to do numerical modeling and visualization in the study of a contemporary event, the pulverizing crash of the Germanwings Flight 9525 on March 24, 2015, as a showcase. Such numerical modeling and the ensuing simulation of aircraft crashes into land or mountain are complex tasks as they involve both theoretical study and supercomputing of a complex physical system. The most tragic type of crash involves ‘pulverization’ such as the one suffered by this Germanwings flight. Here, we show pulverizing airliner crashes by visualization through video animations from supercomputer applications of the numerical modeling tool LS-DYNA. A sound validation process is challenging but essential for any sophisticated calculations. We achieve this by validation against the experimental data from a crash test done in 1993 of an F4 Phantom II fighter jet into a wall. We have developed a method by hybridizing two primary methods: finite element analysis and smoothed particle hydrodynamics . This hybrid method also enhances visualization by showing a ‘debris cloud’. Based on our supercomputer simulations and the visualization, we point out that prior works on this topic based on ‘hollow interior’ modeling can be quite problematic and, thus, not

The advanced role of computational mechanics and visualization in science and technology: analysis of the Germanwings Flight 9525 crash

Science.gov (United States)

Chen, Goong; Wang, Yi-Ching; Perronnet, Alain; Gu, Cong; Yao, Pengfei; Bin-Mohsin, Bandar; Hajaiej, Hichem; Scully, Marlan O.

2017-03-01

Computational mathematics, physics and engineering form a major constituent of modern computational science, which now stands on an equal footing with the established branches of theoretical and experimental sciences. Computational mechanics solves problems in science and engineering based upon mathematical modeling and computing, bypassing the need for expensive and time-consuming laboratory setups and experimental measurements. Furthermore, it allows the numerical simulations of large scale systems, such as the formation of galaxies that could not be done in any earth bound laboratories. This article is written as part of the 21st Century Frontiers Series to illustrate some state-of-the-art computational science. We emphasize how to do numerical modeling and visualization in the study of a contemporary event, the pulverizing crash of the Germanwings Flight 9525 on March 24, 2015, as a showcase. Such numerical modeling and the ensuing simulation of aircraft crashes into land or mountain are complex tasks as they involve both theoretical study and supercomputing of a complex physical system. The most tragic type of crash involves ‘pulverization’ such as the one suffered by this Germanwings flight. Here, we show pulverizing airliner crashes by visualization through video animations from supercomputer applications of the numerical modeling tool LS-DYNA. A sound validation process is challenging but essential for any sophisticated calculations. We achieve this by validation against the experimental data from a crash test done in 1993 of an F4 Phantom II fighter jet into a wall. We have developed a method by hybridizing two primary methods: finite element analysis and smoothed particle hydrodynamics. This hybrid method also enhances visualization by showing a ‘debris cloud’. Based on our supercomputer simulations and the visualization, we point out that prior works on this topic based on ‘hollow interior’ modeling can be quite problematic and, thus, not

ULTRA LOW NOx INTEGRATED SYSTEM FOR NOx EMISSION CONTROL FROM COAL-FIRED BOILERS

Energy Technology Data Exchange (ETDEWEB)

Galen H. Richards; Charles Q. Maney; Richard W. Borio; Robert D. Lewis

2002-12-30

ALSTOM Power Inc.'s Power Plant Laboratories, working in concert with ALSTOM Power's Performance Projects Group, has teamed with the U.S. Department of Energy's National Energy Technology Laboratory (DOE NETL) to conduct a comprehensive study to develop/evaluate low-cost, efficient NOx control technologies for retrofit to pulverized coal fired utility boilers. The objective of this project was to develop retrofit NOx control technology to achieve less than 0.15 lb/MMBtu NOx (for bituminous coals) and 0.10 lb/MMBtu NOx (for subbituminous coals) from existing pulverized coal fired utility boilers at a cost which is at least 25% less than SCR technology. Efficient control of NOx is seen as an important, enabling step in keeping coal as a viable part of the national energy mix in this century, and beyond. Presently 57% of U.S. electrical generation is coal based, and the Energy Information Agency projects that coal will maintain a lead in U.S. power generation over all other fuel sources for decades (EIA 1998 Energy Forecast). Yet, coal-based power is being strongly challenged by society's ever-increasing desire for an improved environment and the resultant improvement in health and safety. The needs of the electric-utility industry are to improve environmental performance, while simultaneously improving overall plant economics. This means that emissions control technology is needed with very low capital and operating costs. This project has responded to the industry's need for low NOx emissions by evaluating ideas that can be adapted to present pulverized coal fired systems, be they conventional or low NOx firing systems. The TFS 2000{trademark} firing system has been the ALSTOM Power Inc. commercial offering producing the lowest NOx emission levels. In this project, the TFS 2000{trademark} firing system served as a basis for comparison to other low NOx systems evaluated and was the foundation upon which refinements were made to further

Effects of calcium magnesium acetate on the combustion of coal-water slurries. Final project report, 1 September 1989--28 February 1993

Energy Technology Data Exchange (ETDEWEB)

Levendis, Y.A.; Wise, D.; Metghalchi, H.; Cumper, J.; Atal, A.; Estrada, K.R.; Murphy, B.; Steciak, J.; Hottel, H.C.; Simons, G.

1993-07-01

To conduct studies on the combustion of coal water fuels (CWFs) an appropriate facility was designed and constructed. The main components were (1) a high-temperature isothermal laminar flow furnace that facilitates observation of combustion events in its interior. The design of this system and its characterization are described in Chapter 1. (2) Apparatus for slurry droplet/agglomerate particle generation and introduction in the furnace. These devices are described in Chapters 1 and 3 and other attached publications. (3) An electronic optical pyrometer whose design, construction theory of operation, calibration and performance are presented in Chapter 2. (4) A multitude of other accessories, such as particle fluidization devices, a suction thermometer, a velocimeter, high speed photographic equipment, calibration devices for the pyrometer, etc., are described throughout this report. Results on the combustion of CWF droplets and CWF agglomerates made from micronized coal are described in Chapter 3. In the same chapter the combustion of CWF containing dissolved calcium magnesium acetate (CMA) axe described. The combustion behavior of pre-dried CWF agglomerates of pulverized grain coal is contrasted to that of agglomerates of micronized coal in Chapter 4. In the same chapter the combustion of agglomerates of carbon black and diesel soot is discussed as well. The effect of CMA on the combustion of the above materials is also discussed. Finally, the sulfur capture capability of CMA impregnated micronized and pulverized bituminous coals is examined in Chapter 5.

Removal of focal atheromatous lesions by angioscopically guided high-speed rotary atherectomy. Preliminary experimental observations

International Nuclear Information System (INIS)

Ahn, S.S.; Auth, D.; Marcus, D.R.; Moore, W.S.

1988-01-01

A new high-speed rotary atherectomy device, inserted over a guide wire and directed with an angioscope, offers the potential of restoring patency of outflow vessels by boring out the atheromatous lesion of the orifices of runoff vessels. The device was tested on 68 cadaver arteries with atheromatous lesions involving the superficial femoral, popliteal, and tibial arteries. This was performed with either free segments or in situ with the device placed through a popliteal arteriotomy. The gross results of rotary atherectomy were assessed by angioscopy, angiography, or both. The luminal surfaces were studied with scanning electron microscopy and transverse sections of vessels were studied with light microscopy. The pulverized atheroma, in colloidal suspension, was analyzed for particle size by Coulter counter. The effect of a colloidal suspension of atheromatous particles on distal capillary circulation was measured in animal experiments. Obstructive lesions were successfully removed in 36 of 37 stenotic arteries (97%) and 18 of 31 completely occluded arteries (58%), an overall efficacy of 54 of 68 (79%). In successfully atherectomized arteries, angioscopy and angiography demonstrated a widely patent, smooth, polished surface. Light microscopy demonstrated removal of the diseased intima with maintenance of the outer media and adventitia. The pulverized atheroma particles were generally smaller than red blood cells and injection of the colloidal atheroma into canine femoral arteries failed to produce local tissue injury. We conclude that in the human cadaver this atherectomy device effectively enlarges and recanalizes obstructed superficial femoral, popliteal, and tibial arteries

Study on flow regimes of high-pressure and dense-phase pneumatic conveying

International Nuclear Information System (INIS)

Lu Peng; Chen Xiaoping; Liang Cai; Pu Wenhao; Zhou Yun; Xu Pan; Zhao Changsui

2009-01-01

High-pressure and dense-phase pneumatic conveying of pulverized coal is a key technology in the field of large-scale entrained bed coal gasification. Flow regime plays an important role in two-phase flow because it affects not only flow behavior and safety operation, but also the reliability of practical processes. Few references and experiences in high-pressure and dense-phase conveying are available, especially for the flow regimes. And because of the high stickiness and electrostatic attraction of pulverized coal to the pipe wall, it is very difficult to make out the flow regimes in the conveying pipe by visualization method. Thus quartz powder was chosen as the conveyed material to study the flow regime. High-speed digital video camera was employed to photograph the flow patterns. Experiments were conducted on a pilot scale experimental setup at the pressure up to 3.6MPa. With the decrease in superficial gas velocity, three distinguishable flow regimes were observed: stratified flow, dune flow and plug flow. The characteristics of pressure traces acquired by high frequency response pressure transmitter and their EMD (Empirical Mode Decomposition) characteristics were correlated strongly with the flow regimes. Combining high-speed photography and pressure signal analysis together can make the recognition of flow patterns in the high-pressure and dense-phase pneumatic conveying system more accurate. The present work will lead to better understanding of the flow regime transition under high-pressure.

Engineering development of advanced coal-fired low-emissions boiler system. Phase II subsystem test design and plan - an addendum to the Phase II RD & T Plan

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-05-01

Shortly after the year 2000 it is expected that new generating plants will be needed to meet the growing demand for electricity and to replace the aging plants that are nearing the end of their useful service life. The plants of the future will need to be extremely clean, highly efficient and economical. Continuing concerns over acid rain, air toxics, global climate changes, ozone depletion and solid waste disposal are expected to further then regulations. In the late 1980`s it was commonly believed that coal-fired power plants of the future would incorporate either some form of Integrated Gasification Combined Cycle (IGCC) or first generation Pressurized Fluidized Bed Combustion (PFBS) technologies. However, recent advances In emission control techniques at reduced costs and auxiliary power requirements coupled with significant improvements In steam turbine and cycle design have clearly indicated that pulverized coal technology can continue to be competitive In both cost and performance. In recognition of the competitive potential for advanced pulverized coal-fired systems with other emerging advanced coal-fired technologies, DOE`s Pittsburgh Energy Technology Center (PETC) began a research and development initiative In late 1990 named, Combustion 2000, with the intention of preserving and expanding coal as a principal fuel In the Generation of electrical power. The project was designed for two stages of commercialization, the nearer-term Low Emission Boiler System (LEBS) program, and for the future, the High Performance Power System (HIPPS) program. B&W is participating In the LEBS program.

Germination and initial development of aroeira (Myracrodruon urundeuva seedlings

Directory of Open Access Journals (Sweden)

Silvana de Paula Quintão Scalon

2012-12-01

Full Text Available Aroeira has great economic importance due to its wood useful, tannins extraction and use in the pharmacology. The aim of this work was to evaluate the germination aspects and initial seedlings development of aroeira, under gibberellins, substrata and shading effects, and for that two experiments were led out. In the first one, seeds were previously soaked for 24 hours in water and in 100 mg.L-1 gibberellin solution and were sowed directly in cells trays in the following substrata: land and sand (1:1 and 1:2 and Plantmax . In the second experiment, 15 cm length seedlings were transplanted to polyethylene sacks filled out land+sand+poultry manure (1:1:1 partly decomposed and they were maintained at greenhouse for 15 days. Soon after, seedlings were transferred for the following conditions: shading (50% and full sun and they were 50 mg.L-1 and 150 mg.L-1 gibberellins solutions pulverized, as control seedlings water pulverized. Aroeira seeds should not be previously water or gibberellins imbibed before being sowed. The best substrata for aroeira seeds germination was Plantmax without germinative treatments to reach higher than 80% of seedlings survival. The seedlings developed better at full sun light and the gibberellin. It was observed increment in height, diameter, foliar area and fresh and dry mass from aerial and root part when compared to shading situation. The gibberellins applications did not influence the aroeira seedlings initial growth characteristics.

Numerical simulations of slagging dynamics using a meshmeshless strategy

Energy Technology Data Exchange (ETDEWEB)

Losurdo, M.; Spliethoff, H. [Technische Universitaet Muenchen (Germany). Lehrstuhl fuer Energiesysteme

2009-07-01

In pulverized co-firing and gasification facilities such as coal and biomass power plants, ash deposition, fouling and slagging, may significantly affect heat exchange and gasification per-formance Deposit growth dramatically increases production loss and may lead to the shut-down of the facility. Computational Fluid Dynamics (CFD) calculations can be used as a valid 'non-intrusive' investigation tool in an efficient problem solving strategy. At TU Munich, an ongoing project aims to develop a dedicated numerical tool to monitor and predict deposition, deposit growth and slagging dynamics in pulverized solid fuel furnaces and gasifiers. A novel in-house code was developed to track solid particles and predict deposit growth and slag dynamics. The adopted numerical strategy uses a Mesh-Meshless approach combined with a Lagrangian particle tracking. Ash particles are tracked in a Lagrangian frame post-processing CFD gas phase results (RANS or LES). Growth and thermo-mechanical proper-ties of the deposit are simultaneously evaluated. Slag dynamics is computed by using a meshless approach: deposit mesh nodes are considered point-mass particles interacting only with mesh connected node-particle neighbours. Forces are modelled applying a visco-elastic model and calculated by means of a Galerking weight (kernel) function. The final goal is to mathematically describe both particle adhesion and slag dynamics applying visco-elastic models using a mesh-meshless approach aiming to investigate slag/slurry dynamics. Pre-liminary numerical results on one layer encourage further development on this subject. (orig.)

Estudio Clínico de Pulpotomía con agregado Trióxido Mineral en 58 Molares Primariosa

OpenAIRE

Isassi Hernández, Hilda

2010-01-01

El formocresol tiene una larga historia en la cual se cuestiona y se reflexiona sobre su uso en Odontopediatría (Fucks y Eidelman; 1991) y ha alcanzado gran popularidad a pesar de no tener atributos curativos de ningún tipo. En una encuesta, Avram y Pulver (1989) informaron que la mayoría de los Odontopediatras de todo el mundo (76.8%) utiliza el formocresol, sin diluir o en una dilución de una quinta parte como medicamento preferido en pulpotomías de dientes primarios vitales, debido a su fá...

Vývoj HPLC metody pro stanovení vitaminu E v přípravku geladrink

OpenAIRE

Švestková, Petra

2010-01-01

A HPLC method was developed for the determination of content of vitamine E acetate in preparation Geladrink Forte pulverized drink - pineapple. The method is based on using Chromolith Performance RP-18e column (100 x 4.6 mm) and UV detection at 290 nm. The vitamine E acetate was separated in the presence of internal standard tocol from ballast matrix. It was used isocratic elution of the mobile phase methanol:water (98:2) at a flow-rate of 1.5 ml/min. There was temperature 30 řC during the me...

Model technique for aerodynamic study of boiler furnace

Energy Technology Data Exchange (ETDEWEB)

1966-02-01

The help of the Division was recently sought to improve the heat transfer and reduce the exit gas temperature in a pulverized-fuel-fired boiler at an Australian power station. One approach adopted was to construct from Perspex a 1:20 scale cold-air model of the boiler furnace and to use a flow-visualization technique to study the aerodynamic patterns established when air was introduced through the p.f. burners of the model. The work established good correlations between the behaviour of the model and of the boiler furnace.

Investigation of the submodels for combustion; Polton osamallien kaeytettaevyys

Energy Technology Data Exchange (ETDEWEB)

Kjaeldman, L.; Huttunen, M.; Kyttaelae, J. [VTT Energy, Espoo (Finland)

1997-10-01

The capability for numerical analysis of flow, combustion and heat transfer in furnaces has been developed by improving the knowledge of the sensitivity of computed results on submodels recently implemented to the computational environment Ardemus owned by VTT Energy and Imatran Voima Oy. The submodels studied include models for combustion of gaseous (pyrolysed) fuel and for nitric oxide. The cases investigated included a gas flame and pulverized coal and peat combustion in single burner furnaces. The effect of grid refinement on the results was investigated for a corner fired power station furnace. (orig.)

Bag filters

Energy Technology Data Exchange (ETDEWEB)

Yoshida, M; Komeda, I; Takizaki, K

1982-01-01

Bag filters are widely used throughout the cement industry for recovering raw materials and products and for improving the environment. Their general mechanism, performance and advantages are shown in a classification table, and there are comparisons and explanations. The outer and inner sectional construction of the Shinto ultra-jet collector for pulverized coal is illustrated and there are detailed descriptions of dust cloud prevention, of measures used against possible sources of ignition, of oxygen supply and of other topics. Finally, explanations are given of matters that require careful and comprehensive study when selecting equipment.

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

International Nuclear Information System (INIS)

Anon.

1982-01-01

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

Application and demonstration of oxyfuel combustion technologies to the existing power plant in Australia

Energy Technology Data Exchange (ETDEWEB)

Uchida, Terutoshi; Yamada, Toshihiko; Watanabe, Shuzo; Kiga, Takashi; Gotou, Takahiro [IHI Corporation, Tokyo (Japan). Power Plant Div.; Misawa, Nobuhiro [Electric Power Development Co., Ltd., Tokyo (Japan); Spero, Chris [CS Energy Ltd, Brisbane (Australia)

2013-07-01

Oxyfuel combustion is able to directly make the highly concentrated CO{sub 2} from the flue gas of pulverized coal fired power plant and, therefore, is expected as one of the promising technologies for CO{sub 2} capture. We are advancing the Oxyfuel combustion demonstration project, which is called Callide Oxyfuel Project, with the support of both Australian and Japanese governments. Currently the boiler retrofit work is completed and the commissioning in air combustion is going on. In this paper, we introduce the general outline of the Callide Oxyfuel Project and its progress.

CFD simulation of coal and straw co-firing

DEFF Research Database (Denmark)

Junker, Helle; Hvid, Søren L.; Larsen, Ejvind

This paper presents the results of a major R&D program with the objective to develop CFD based tools to assess the impact of biomass co-firing in suspension fired pulverized coal power plants. The models have been developed through a series of Danish research projects with the overall objective...... to collect results from fundamental research and make it operational in boiler design through implementation in a Computational Fluid Dynamics based simulation tool. This paper summarizes the developments in modeling of; particle motion, particle conversion, ash deposition on heat transfer surfaces, and NOx...

Fuel Quality Impact in a Historical Perspective: A Review of 25 Years of EU-Funded Research on Fuel Characterization, Ash and Deposit Formation, and Corrosion

DEFF Research Database (Denmark)

Jappe Frandsen, Flemming; Fendt, Sebastian; Spliethoff, Hartmut

2016-01-01

friendly conditions. In order to reach these goals, and to enable a secure and nearly carbon neutral heat and power generation, recently, the Biofficiency proposal, was granted under Horizon2020, aiming to: Develop next generation, biomass-fired CHP plant, increasing the steamtemperatures up to 600°C...... and by intelligent plant design. Broaden the feedstocks for pulverized fuel (PF) and fluidized bed (FB) powerplants, using pre-treatment methods with focus on the reduction of harmful,inorganic elements: Cl, S and the alkali metals. Prevent power plant damage due to high-temperature Cl-induced corrosion. Reduce...

Photon activation analysis of trace metals in the livers and spleens of pigs

International Nuclear Information System (INIS)

Fukushima, M.

1995-01-01

Nondestructive photon activation analysis with 30 MeV bremsstrahlung was applied to determine trace element concentrations in the livers and spleens of five pigs. Samples were freeze-dried, pulverized and fractionated into four groups corresponding mesh size ; smaller than 60 mesh, 60-100 mesh, 100-200 mesh and larger than 200 mesh. Up to 9 elements in each fraction were analyzed. The concentrations of Br, Fe, Mg, Mn, Mo, Na, Rb and Zn in each liver fractions were almost constant, as were concentrations of Mg and Rb in spleens. (author). 10 refs., 7 tabs

Development of Bi-Sb-Te ternary alloy with compositionally graded structure

Energy Technology Data Exchange (ETDEWEB)

Yamamoto, A; Ohta, T

1997-07-01

Compositionally graded p-type Bi-Sb-Te thermoelectric material was synthesized by PIES (Pulverized and Intermixed Elements Sintering) method. The materials consisted of three segmented regions of different alloy composition, i.e., y = 0.8/0.825/0.9 in (Bi{sub 2}Te{sub 3}){sub 1{minus}y} (Sb{sub 2}Te{sub 3}){sub y} system. It was found that the electrical power output of the compositionally graded material was larger than that of the best single composition material when the temperature difference was the designed value.

Coal liquefaction in an inorganic-organic medium. [DOE patent application

Science.gov (United States)

Vermeulen, T.; Grens, E.A. II; Holten, R.R.

Improved process for liquefaction of coal by contacting pulverized coal in an inorganic-organic medium solvent system containing a ZnCl/sub 2/ catalyst, a polar solvent with the structure RX where X is one of the elements O, N, S, or P, and R is hydrogen or a lower hydrocarbon radical; the solvent system can contain a hydrogen donor solvent (and must when RX is water) which is immiscible in the ZnCl/sub 2/ and is a hydroaromatic hydrocarbon selected from tetralin, dihydrophenanthrene, dihydroanthracene or a hydrogenated coal derived hydroaromatic hydrocarbon distillate fraction.

High pressure MHD coal combustors investigation, phase 2

Science.gov (United States)

Iwata, H.; Hamberg, R.

1981-05-01

A high pressure MHD coal combustor was investigated. The purpose was to acquire basic design and support engineering data through systematic combustion experiments at the 10 and 20 thermal megawatt size and to design a 50 MW/sub t/ combustor. This combustor is to produce an electrically conductive plasma generated by the direct combustion of pulverized coal with hot oxygen enriched vitiated air that is seeded with potassium carbonate. Vitiated air and oxygen are used as the oxidizer, however, preheated air will ultimately be used as the oxidizer in coal fired MHD combustors.

Clean coal reference plants: Pulverized coal boiler with flue gas desulfurization. Topical report

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

The Clean Coal Technology Demonstration Program (CCT) is a government and industry cofunded technology development effort to demonstrate a new generation of innovative coal utilization processes in a series of full-scale facilities. The goal of the program is to provide the U.S. energy marketplace with a number of advanced, more efficient, and environmentally responsive coal-using technologies. To achieve this goal, a multiphased effort consisting of five separate solicitations has been completed. The Morgantown Energy Technology Center (METC) has the responsibility for monitoring the CCT Projects within certain technology categories, which, in general, correspond to the center`s areas of technology development. Primarily the categories of METC CCT projects are: atmospheric fluid bed combustion, pressurized fluidized bed combustion, integrated gasification combined cycle, mild gasification, and industrial applications.

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

Energy Technology Data Exchange (ETDEWEB)

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

2008-07-15

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

Water use at pulverized coal power plants with postcombustion carbon capture and storage.

Science.gov (United States)

Zhai, Haibo; Rubin, Edward S; Versteeg, Peter L

2011-03-15

Coal-fired power plants account for nearly 50% of U.S. electricity supply and about a third of U.S. emissions of CO(2), the major greenhouse gas (GHG) associated with global climate change. Thermal power plants also account for 39% of all freshwater withdrawals in the U.S. To reduce GHG emissions from coal-fired plants, postcombustion carbon capture and storage (CCS) systems are receiving considerable attention. Current commercial amine-based capture systems require water for cooling and other operations that add to power plant water requirements. This paper characterizes and quantifies water use at coal-burning power plants with and without CCS and investigates key parameters that influence water consumption. Analytical models are presented to quantify water use for major unit operations. Case study results show that, for power plants with conventional wet cooling towers, approximately 80% of total plant water withdrawals and 86% of plant water consumption is for cooling. The addition of an amine-based CCS system would approximately double the consumptive water use of the plant. Replacing wet towers with air-cooled condensers for dry cooling would reduce plant water use by about 80% (without CCS) to about 40% (with CCS). However, the cooling system capital cost would approximately triple, although costs are highly dependent on site-specific characteristics. The potential for water use reductions with CCS is explored via sensitivity analyses of plant efficiency and other key design parameters that affect water resource management for the electric power industry.

Research on pyrolysis characteristics and kinetics of super fine and conventional pulverized coal

International Nuclear Information System (INIS)

Zhang Chaoqun; Jiang Xiumin; Wei Lihong; Wang Hui

2007-01-01

Based on isothermal thermogravimetric analysis (TGA) and kinetic equations, the optimization toolbox of MATLAB was applied to study the effects of particle size and heating rate on the pyrolysis characteristics and kinetics and to obtain the mechanism function and kinetic parameters of Yuanbaoshan coal at four different particle sizes and heating rates. The pyrolysis characteristics of the samples were analyzed using thermogravimetric (TG) curves and differential thermogravimetric (DTG) curves. The results show that the coal pyrolysis process is strongly affected by heating rate and particle size. As the heating rate increases, the temperature of volatile matter initiation increases, the total volatile matter evolved decreases and the DTG peak shifts toward higher temperature. As the particle size decreases, the temperature of volatile matter initiation of the coal sample decreases and the maximum rate of mass loss increases. In the pyrolysis of coal, the activation energies of the samples were found to increase with growing particle size and decreasing heating rate for both of the devolatilization temperature stages. In the lower temperature stage, the coal samples show a great difference in mechanism function at different particle sizes and heating rates

Crystalline structure of pulverized dental calculus induces cell death in oral epithelial cells.

Science.gov (United States)

Ziauddin, S M; Yoshimura, A; Montenegro Raudales, J L; Ozaki, Y; Higuchi, K; Ukai, T; Kaneko, T; Miyazaki, T; Latz, E; Hara, Y

2018-06-01

Dental calculus is a mineralized deposit attached to the tooth surface. We have shown that cellular uptake of dental calculus triggers nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome activation, leading to the processing of the interleukin-1β precursor into its mature form in mouse and human phagocytes. The activation of the NLRP3 inflammasome also induced a lytic form of programmed cell death, pyroptosis, in these cells. However, the effects of dental calculus on other cell types in periodontal tissue have not been investigated. The aim of this study was to determine whether dental calculus can induce cell death in oral epithelial cells. HSC-2 human oral squamous carcinoma cells, HOMK107 human primary oral epithelial cells and immortalized mouse macrophages were exposed to dental calculus or 1 of its components, hydroxyapatite crystals. For inhibition assays, the cells were exposed to dental calculus in the presence or absence of cytochalasin D (endocytosis inhibitor), z-YVAD-fmk (caspase-1 inhibitor) or glyburide (NLRP3 inflammasome inhibitor). Cytotoxicity was determined by measuring lactate dehydrogenase (LDH) release and staining with propidium iodide. Tumor necrosis factor-α production was quantified by enzyme-linked immunosorbent assay. Oral epithelial barrier function was examined by permeability assay. Dental calculus induced cell death in HSC-2 cells, as judged by LDH release and propidium iodide staining. Dental calculus also induced LDH release from HOMK107 cells. Following heat treatment, dental calculus lost its capacity to induce tumor necrosis factor-α in mouse macrophages, but could induce LDH release in HSC-2 cells, indicating a major role of inorganic components in cell death. Hydroxyapatite crystals also induced cell death in both HSC-2 and HOMK107 cells, as judged by LDH release, indicating the capacity of crystal particles to induce cell death. Cell death induced by dental calculus was significantly inhibited by cytochalasin D, z-YVAD-fmk and glyburide, indicating NLRP3 inflammasome involvement. In permeability assays, dental calculus attenuated the barrier function of HSC-2 cell monolayers. Dental calculus induces pyroptotic cell death in human oral epithelial cells and the crystalline structure plays a major role in this process. Oral epithelial cell death induced by dental calculus might be important for the etiology of periodontitis. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

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

DEFF Research Database (Denmark)

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

2014-01-01

A number of full-scale deposit probe measuring campaigns conducted in grate-fired and suspension-fired boilers, fired with biomass, have been reviewed and compared. The influence of operational parameters on the chemistry of ash and deposits, on deposit build-up rates, and on shedding behavior has...... of the deposits formed is determined by the fly ash composition and the flue gas temperature; increases in the local flue gas temperature lead to higher contents of Si and Ca and lower contents of Cl in the deposits. The net deposit build-up rates in grate-fired and suspension-fired boilers are at similar levels....../wood-firing in suspension-fired boilers, shedding occurred by debonding with incomplete removal at flue gas temperatures of 600–1000 °C and by debonding with complete removal during wood-firing in suspension-fired boilers at high flue gas temperatures (1300 °C). Shedding events were not observed during wood suspension...

Techno-Economic Analysis of a 600 MW Oxy-Enrich Pulverized Coal-Fired Boiler

Directory of Open Access Journals (Sweden)

Ming Lei

2018-03-01

Full Text Available Oxy-fuel combustion is one of the most promising methods for CO2 capture and storage (CCS but the operating costs—mainly due to the need for oxygen production—usually lead to an obvious decrease in power generation efficiency. An “oxy-enrich combustion” process was proposed in this study to improve the efficiency of the oxy-fuel combustion process. The oxidizer for oxy-enrich combustion was composed of pure oxygen, air and recycled flue gas. Thus, the CO2 concentration in the flue gas decreased to 30–40%. The PSA (pressure swing adsorption, which has been widely used for CO2 removal from the shifting gases of ammonia synthesis in China, was applied to capture CO2 during oxy-enrich combustion. The technological economics of oxy-enrich combustion with PSA was calculated and compared to that of oxy-fuel combustion. The results indicated that, compared with oxy-fuel combustion: (1 the oxy-enrich combustion has fewer capital and operating costs for the ASU (air separation unit and the recycle fan; (2 there were fewer changes in the components of the flue gas in a furnace for oxy-enrich combustion between dry and wet flue gas circulation; and (3 as the volume ratio of air and oxygen was 2 or 3, the economics of oxy-enrich combustion with PSA were more advantageous.

Chemical analysis of surfaces by resonance ionization mass spectroscopy associated to ionic pulverization

International Nuclear Information System (INIS)

Kern, P.

1995-01-01

This work shows that if resonance ionization mass spectroscopy was first applied in isotopic separation, it's also an analyzing method adapted to the study of semi-conductor materials and thin foils. We have improved this technic: a neodymium laser coupled with a dye laser, a new argon ions gun, a gallium ions gun and a new collection optic for the secondary ions quadrupole spectrometer to allow quantitative and selective measurements. (S.G.). 84 refs

Influence of rank and macerals on the burnout behaviour of pulverized Indian coal

Energy Technology Data Exchange (ETDEWEB)

Choudhury, Nandita; Biswas, S.; Sarkar, P.; Kumar, Manish; Mukherjee, A.; Choudhury, A. [Central Institute of Mining and Fuel Research, Digwadih Campus (Formerly Central Fuel Research Institute), P.O. FRI, Dhanbad-828 108, Jharkhand (India); Ghosal, Sujit; Mitra, Tandra [Jadavpur University, Kolkata-700 032, West Bengal (India)

2008-04-03

The combustion behaviour of coal is significantly influenced by its rank and maceral and microlithotype compositions. Different macerals, due to their distinct and unique physical properties and chemical makeup, have different burning characteristics. This paper deals with the burning behaviour of coals of Indian origin by thermo gravimetric analysis (TGA) and in drop tube furnace (DTF) with particular emphasis on the role of macerals and their associations. Four coals of different rank and petrographic makeup, along with their two density fractions, with enriched vitrinite and inertinites, respectively,were studied in both TGA and DTF. The burnout behaviour was estimated from the chemical analyses of the char samples collected from the DTF. The burning characteristics of one of the coals deviate from the trend expected with the variations of rank. The behaviour of the density fractions in DTF was found to be different from that observed in TGA analyses. An attempt has been made to correlate the burnout with the petrographic macerals and microlithotypes present in the coals. The morphology of the residual chars indicates the contributions of the inertinites towards the formation of cenospheres and network types of reactive chars. The superior burning behaviour of the higher density inertinite-rich fractions over the raw coals and also some vitrinite-rich fractions indicate the better reactivity of the inertinites towards combustion. (author)

The effect of char structure on burnout during pulverized coal combustion at pressure

Energy Technology Data Exchange (ETDEWEB)

Liu, G.; Wu, H.; Benfell, K.E.; Lucas, J.A.; Wall, T.F.

1999-07-01

An Australian bituminous coal sample was burnt in a drop tube furnace (DTF) at 1 atm and a pressurized drop tube furnace (PDTF) at 15 atm. The char samples were collected at different burnout levels, and a scanning electron microscope was used to examine the structures of chars. A model was developed to predict the burnout of char particles with different structures. The model accounts for combustion of the thin-walled structure of cenospheric char and its fragmentation during burnout. The effect of pressure on reaction rate was also considered in the model. As a result, approximately 40% and 70% cenospheric char particles were observed in the char samples collected after coal pyrolysis in the DTF and PDTF respectively. A large number of fine particles (< 30 mm) were observed in the 1 atm char samples at burnout levels between 30% and 50%, which suggests that significant fragmentation occurred during early combustion. Ash particle size distributions show that a large number of small ash particles formed during burnout at high pressure. The time needed for 70% char burnout at 15 atm is approximately 1.6 times that at 1 atm under the same temperature and gas environment conditions, which is attributed to the different pressures as well as char structures. The overall reaction rate for cenospheric char was predicted to be approximately 2 times that of the dense chars, which is consistent with previous experimental results. The predicted char burnout including char structures agrees reasonably well with the experimental measurements that were obtained at 1 atm and 15 atm pressures.

Staged combustion - main method for suppressing nitrogen oxides in pulverized-coal fired boilers

Energy Technology Data Exchange (ETDEWEB)

Kotler, V.R. (Vsesoyuznyi Teplotekhnicheskii Institut (USSR))

1989-08-01

Describes principles behind staged combustion, which is based on organizing furnace operations so that only part of the air from the fuel is taken into the furnace. The remaining air, which is needed for combustion, is fed as a tertiary blast jet into the intermediate flame zone. Following inflammation and combustion of the volatile matter, the oxygen concentration in the flame drops sharply causing a retardation of the oxidation reactions forming NO and an intensification of the reactions causing the nitrogen-containing radicals NH{sub i} and CN to be converted into N{sub 2}. When the reducing agents CO, H{sub 2} and CH{sub 4} are present in certain flame zones, even the nitrogen oxide is reduced to N{sub 2}. The NO concentrations in the flame are reduced until the jet of tertiary air is introduced. Discusses with reference to practice in the USA and Western Europe how to achieve maximum effect of this method for different types of boiler and presents the results of observations of the introduction of staged combustion to the BKZ-210-140 boiler burning Kuznetsk gassy coal. 5 refs.

Study of sodium combustion and fire extinction by pulverized substances. Role of additives

International Nuclear Information System (INIS)

Reuillon, Marcelline.

1976-01-01

A study is presented on inflammation and combustion of liquid sodium, extinction of the metal fires by comburant concentration reducing and cooling, liquid covering, powder smothering. The role of the additives is discussed. The setting up and the experimental process are given. The sodium combustion residues are analyzed. Various powder mixtures based on alkaline carbonates, NaCl-Na 2 CO 3 , NaCl-Na 2 CO 3 ,H 2 O etc... are studied. An attempt of interpretation on sodium fire extinction is presented [fr

Process to refine flyash captured from pulverized coal fired boilers and auxiliary equipment

International Nuclear Information System (INIS)

Borowy, W.J.

1991-01-01

This patent describes a separating and refining process for particulate that has been removed from the exhaust gases of an organic fuel combustion process. It includes determining relative sizes of carbon rich and carbon lean particles that are found in the exhaust gases for the combustion process; supplying the particulate matter from the exhaust of the combustion process; providing a means for conveying the particulate matter between the following steps; separating, by size, coarse and fine particles in the exhaust particulate so as to yield carbon rich and carbon lean fractions

Induction of chromosome aberrations and mitotic arrest by cytomegalovirus in human cells

International Nuclear Information System (INIS)

AbuBakar, S.; Au, W.W.; Legator, M.S.; Albrecht, T.

1988-01-01

Human cytomegalovirus (CMV) is potentially an effective but often overlooked genotoxic agent in humans. We report here evidence that indicates that infection by CMV can induce chromosome alterations and mitotic inhibition. The frequency of chromosome aberrations induced was dependent on the input multiplicity of infection (m.o.i.) for human lung fibroblasts (LU), but not for human peripheral blood lymphocytes (PBLs) when both cell types were infected at the GO phase of the cell cycle. The aberrations induced by CMV were mostly chromatid breaks and chromosome pulverizations that resembled prematurely condensed S-phase chromatin. Pulverized chromosomes were not observed in LU cells infected with virus stocks that had been rendered nonlytic by UV-irradiation at 24,000 ergs/mm2 or from infection of human lymphocytes. In LU cells infected with UV-irradiated CMV, the frequency of aberrations induced was inversely dependent on the extent of the exposure of the CMV stock to the UV-light. In permissive CMV infection of proliferating LU cells at 24 hr after subculture, a high percentage (greater than 40%) of the metaphase cells were arrested at their first metaphase and displayed severely condensed chromosomes when harvested 48 hr later. A significant increase (p less than 0.05) in the chromosome aberration frequency was also observed. Our study shows that CMV infection is genotoxic to host cells. The types and extent of damage are dependent on the viral genome expression and on the cell cycle stage of the cells at the time of infection. The possible mechanisms for induction of chromosome damage by CMV are discussed

Constructal design of a blast furnace iron-making process based on multi-objective optimization

International Nuclear Information System (INIS)

Liu, Xiong; Chen, Lingen; Feng, Huijun; Qin, Xiaoyong; Sun, Fengrui

2016-01-01

For the fixed total raw material cost and based on constructal theory and finite time thermodynamics, a BFIM (blast furnace iron-making) process is optimized by taking a complex function as optimization objective. The complex function is integrated with HM (hot metal) yield and useful energy of the BF (blast furnace). The optimal cost distribution of raw materials (namely “generalized optimal construct”) is obtained. The effects of some parameters, such as oxygen enrichment, blast temperature and pulverized coal dosage, on the optimization results are analyzed. The results show that the HM yield, useful energy and complex function are, respectively, increased by 3.13%, 2.66% and 2.90% after generalized constructal optimization. The utilization efficiencies of the BFG (blast furnace gas) and slag are 41.3% and 57.1%, respectively, which means that the utilization potentials of the BFG and slag can be further exploited. Increasing pulverized coal dosage and decreasing the agglomerate ratio can increase the complex function. The performance the BFIM process can be improved by adjusting the oxygen enrichment, blast temperature, blast dosage, pressure ratio of the Brayton cycle's air compressor and relative pressure drop of the air compressor inlet to their optimal values, respectively, which are new findings of this paper. - Highlights: • Constructal optimization of a blast furnace iron-making process is performed. • Finite time thermodynamic model of open Brayton cycle is adopted. • Weighting function is taken as optimization objective. • Optimal cost distribution of the raw materials is obtained.

Distinctive features of high-ash bituminuos coals combution with low milling fineness in furnace chambers with bottom blowing

Science.gov (United States)

Zroychikov, N. A.; Kaverin, A. A.; Biryukov, Ya A.

2017-11-01

Nowadays the problem of improvement of pulverized coal combustion schemes is an actual one for national power engineering, especially for combustion of coals with low milling fineness with significant portion of moisture or mineral impurities. In this case a big portion of inert material in the fuel may cause impairment of its ignition and combustion. In addition there are a lot of boiler installations on which nitrogen oxides emission exceeds standard values significantly. Decreasing of milling fineness is not without interest as a way of lowering an electric energy consumption for pulverization, which can reach 30% of power plant’s auxiliary consumption of electricity. Development of a combustion scheme meeting the requirements both for effective coal burning and environmental measures (related to NOx emission) is a complex task and demands compromising between these two factors, because implementation of NOx control by combustion very often leads to rising of carbon-in-ash loss. However widespread occurrence of such modern research technique as computer modeling allows to conduct big amount of variants calculations of combustion schemes with low cost and find an optimum. This paper presents results of numerical research of combined schemes of coal combustion with high portion of inert material based on straight-flow burners and nozzles. Several distinctive features of furnace aerodynamics, heat transfer and combustion has been found. The combined scheme of high-ash bituminouos coals combustion with low milling fineness, which allows effective combustion of pointed type of fuels with nitrogen oxides emission reduction has been proposed.

Mechanisms of improving the cyclic stability of V-Ti-based hydrogen storage electrode alloys

International Nuclear Information System (INIS)

Miao He; Wang Weiguo

2010-01-01

Research highlights: → The corrosion resistance of V-based phase is much lower than that of C14 Laves phase of V-Ti-based alloys. → The addition of Cr which mostly distributes in V-based phase can effectively increase the anti-corrosion ability of V-Ti-based alloys. → The addition of Cr which mostly distributes in V-based phase can effectively increase the anti-corrosion ability of V-Ti-based alloys. - Abstract: In this work, the mechanisms of improving the cyclic stability of V-Ti-based hydrogen storage electrode alloys were investigated systemically. Several key factors for example corrosion resistance, pulverization resistance and oxidation resistance were evaluated individually. The V-based solid solution phase has much lower anti-corrosion ability than C14 Laves phase in KOH solution, and the addition of Cr in V-Ti-based alloys can suppress the dissolution of the main hydrogen absorption elements of the V-based phase in the alkaline solution. During the charge/discharge cycling, the alloy particles crack or break into several pieces, which accelerates their corrosion/oxidation and increases the contact resistance of the alloy electrodes. Proper decreasing the Vickers hardness and enhancing the fracture toughness can increase the pulverization resistance of the alloy particles. The oxidation layer thickness on the alloy particle surface obviously increases during charge/discharge cycling. This deteriorates their electro-catalyst activation to the electrochemical reaction, and leads to a quick degradation. Therefore, enhancing the oxide resistance can obviously improve the cyclic stability of V-Ti-based hydrogen storage electrode alloys.

Utilizing Philippine Calatrava coal-diesel oil mixture (CDOM) as alternative fuel for industrial steam generator

Energy Technology Data Exchange (ETDEWEB)

Archie B. Maglaya [De La Salle University, Manila (Philippines). Department of Mechanical Engineering

2005-01-01

The fast depletion of fuel oil and the continuous increase in the demand for power is a global issue. In the Philippines, the demand for diesel oil is expected to increase significantly in a 20-year period as projected by the Department of Energy. In line with the Philippine Government's thrust to lessen the dependence on imported energy, the agenda for the search for alternative fuel is highly prioritized. Thus, this paper presents the results of the study on performance analysis and efficiency test of a diesel oil fired industrial steam generator using Philippine Calatrava coal-diesel oil mixture (CDOM) as alternative fuel. A computer program was developed in HyperText Markup Language (HTML{copyright}) and JavaScript{copyright} to aid the computation of the adiabatic flame temperature from the governing system of equations based on the heat interaction between CDOM fuel, combustion air and products of combustion to determine the most desirable alternative fuel. Actual experimentation for the determination of CDOM fuel properties was also conducted to verify the alternative fuel selected through theoretical calculations. Results showed that the CDOM fuel with a particle size passing 75 {mu}m (-200 mesh) sieve having a proportion of 5% pulverized coal-95% diesel oil and 10% pulverized coal-90% diesel oil could be handled throughout the test with no degradation of the industrial steam generator. The steam generator efficiency using diesel oil is close to the steam generator efficiency using both CDOM fuels. 20 refs., 5 figs., 4 tabs.

Study of ignition, combustion, and production of harmful substances upon burning solid organic fuel at a test bench with a vortex chamber

Science.gov (United States)

Burdukov, A. P.; Chernetskiy, M. Yu.; Dekterev, A. A.; Anufriev, I. S.; Strizhak, P. A.; Greben'kov, P. Yu.

2016-01-01

Results of investigation of furnace processes upon burning of pulverized fuel at a test bench with a power of 5 MW are presented. The test bench consists of two stages with tangential air and pulverized coal feed, and it is equipped by a vibrocentrifugal mill and a disintegrator. Such milling devices have an intensive mechanical impact on solid organic fuel, which, in a number of cases, increases the reactivity of ground material. The processes of ignition and stable combustion of a mixture of gas coal and sludge (wastes of concentration plant), as well as Ekibastus coal, ground in the disintegrator, were studied at the test bench. The results of experimental burning demonstrated that preliminary fuel grinding in the disintegrator provides autothermal combustion mode even for hardly inflammable organic fuels. Experimental combustion of biomass, wheat straw with different lignin content (18, 30, 60%) after grinding in the disintegrator, was performed at the test bench in order to determine the possibility of supporting stable autothermal burning. Stable biofuel combustion mode without lighting by highly reactive fuel was achieved in the experiments. The influence of the additive GTS-Powder (L.O.M. Leaders Co., Ltd., Republic of Korea) in the solid and liquid state on reducing sulfur oxide production upon burning Mugun coal was studied. The results of experimental combustion testify that, for an additive concentration from 1 to 15% of the total mass of the burned mixture, the maximum SO2 concentration reduction in ejected gases was not more than 18% with respect to the amount for the case of burning pure coal.

Surface tiny grain-dependent enhanced rate performance of MoO3 nanobelts with pseudocapacitance contribution for lithium-ion battery anode

Science.gov (United States)

Cao, Liyun; He, Juju; Li, Jiayin; Yan, Jingwen; Huang, Jianfeng; Qi, Ying; Feng, Liangliang

2018-07-01

In order to improve the rate performance of MoO3, a novel MoO3 nanobelt with tiny grains on surface (named as d-MoO3) is fabricated via one-step facile hydrothermal method with citric acid adding, in which citric acid (CA) serves as a weak reductant as well as surface modification agent. When tested as an anode in LIBs, d-MoO3 displays an improved discharge capacity of 787 mAh·g-1 at 0.1 A g-1 over 100 cycles with capacity retention of ∼91% while MoO3 decays to 50 mAh·g-1 in the 100th cycle. Notably, d-MoO3 delivers enhanced rate capability (536 and 370 mAh·g-1 at high rates of 5 and 10 A g-1 respectively). We consider these excellent electrochemical properties of d-MoO3 electrode are associated with the tiny grains on MoO3 surface, which effectively maintains the electrode's structural integrity. Even though d-MoO3 nanobelt suffers from a degree of in-situ pulverization after several cycles, these pulverized active particles can still maintain stable electrochemical contact and are highly exposed to electrolyte, realizing ultrahigh e-/Li+ diffusion kinetics. In addition, part extrinsic pseudocapacitance contribution to the Li+ storage also explains the high-rate performance. Combining all these merits, d-MoO3 is potentially a high-energy, high-power and well-stable anode material for Li ion batteries (LIBs).

Vermi composting--organic waste management and disposal.

Science.gov (United States)

Kumar, J Sudhir; Subbaiah, K Venkata; Rao, P V V Prasada

2012-01-01

Solid waste is an unwanted byproduct of modern civilization. Landfills are the most common means of solid waste disposal. But the increasing amount of solid waste is rapidly filling existing landfills, and new sites are difficult to establish. Alternatives to landfills include the use of source reduction, recycling, composting and incineration, as well as use of landfills. Incineration is most economical if it includes energy recovery from the waste. Energy can be recovered directly from waste by incineration or the waste can be processed to produce storable refuse derived fuel (RDF). Information on the composition of solid wastes is important in evaluating alternative equipment needs, systems, management programs and plans. Pulverization of municipal solid waste is done and the pulverized solid waste is dressed to form a bed and the bed is fed by earthworms which convert the bed into vermi compost. The obtained vermi compost is sent to Ministry of Environment & Forests (MoEF) recognized lab for estimating the major nutrients, i.e. Potassium (K), Phosphorous (P), Nitrogen (N) and Micro-nutrient values. It is estimated that 59 - 65 tons of wet waste can be collected in a town per day and if this wet waste is converted to quality compost, around 12.30 tons of vermi compost can be generated. If a Municipal Corporation manages this wet waste an income of over (see text symbol) for 0.8 9 crore per anum can be earned which is a considerable amount for providing of better services to public.

Novel approaches in advanced combustion characterization of fuels for advanced pressurized combustion

Energy Technology Data Exchange (ETDEWEB)

Aho, M.; Haemaelaeinen, J. [VTT Energy (Finland); Joutsenoja, T. [Tampere Univ. of Technology (Finland)

1996-12-01

This project is a part of the EU Joule 2 (extension) programme. The objective of the research of Technical Research Centre of Finland (VTT) is to produce experimental results of the effects of pressure and other important parameters on the combustion of pulverized coals and their char derivates. The results can be utilized in modelling of pressurized combustion and in planning pilot-scale reactors. The coals to be studied are Polish hvb coal, French lignite (Gardanne), German anthracite (Niederberg) and German (Goettelbom) hvb coal. The samples are combusted in an electrically heated, pressurized entrained flow reactor (PEFR), where the experimental conditions are controlled with a high precision. The particle size of the fuel can vary between 100 and 300 {mu}m. The studied things are combustion rates, temperatures and sizes of burning single coal and char particles. The latter measurements are performed with a method developed by Tampere University of Technology, Finland. In some of the experiments, mass loss and elemental composition of the char residue are studied in more details as the function of time to find out the combustion mechanism. Combustion rate of pulverized (140-180 {mu}m) Gardanne lignite and Niederberg anthracite were measured and compared with the data obtained earlier with Polish hvb coal at various pressures, gas temperatures, oxygen partial pressures and partial pressures of carbon dioxide in the second working period. In addition, particle temperatures were measured with anthracite. The experimental results were treated with multivariable partial least squares (PLS) method to find regression equation between the measured things and the experimental variables. (author)

Blocky craters: implications about the lunar megaregolith

International Nuclear Information System (INIS)

Thompson, T.W.; Roberts, W.J.; Hartmann, W.K.; Shorthill, R.W.; Zisk, S.H.

1979-01-01

Radar, infrared, and photogeologic properties of lunar craters have been studied to determine whether there is a systematic difference in blocky craters between the maria and terrae and whether this difference may be due to a deep megaregolith of pulverized material forming the terra surface, as opposed to a layer of semi-coherent basalt flows forming the mare surface. Some 1310 craters from about 4 to 100 km diameter have been catalogued as radar and/or infrared anomalies. In addition, a study of Apollo Orbital Photography confirmed that the radar and infrared anomalies are correlated with blocky rubble around the crater. Analysis of the radar and infrared data indicated systematic terra-mare differences. Fresh terra craters smaller than 12 km were less likely to be infrared and radar anomalies than comparable mare craters: but terra and mare craters larger than 12 km had similar infrared and radar signatures. Also, there are many terra craters which are radar bright but not infrared anomalies. The authors interpretation of these data is that while the maria are rock layers (basaltic flow units) where craters eject boulder fields, the terrae are covered by relatively pulverized megaregolith at least 2 km deep, where craters eject less rocky rubble. Blocky rubble, either in the form of actual rocks or partly consolidated blocks, contributes to the radar and infrared signatures of the crater. However, aging by impacts rapidly destroys these effects, possibly through burial by secondary debris or by disintegration of the blocks themselves, especially in terra regions. (Auth.)

Investigating coseismic fracture damage using a new high speed triaxial apparatus

Science.gov (United States)

Mitchell, T. M.; Aben, F. M.; Pricci, R.; Brantut, N.; Rockwell, T. K.; Boon, S.

2017-12-01

The occurence of pulverized rocks, a type of intensely damaged fault rock which has undergone minimal shear strain, has been linked to damage induced by transient high strain-rate stress perturbations during earthquake rupture. Damage induced by such transient stresses, whether compressional or tensional, likely constitute heterogeneous modulations of the remote stresses that will impart significant changes on the strength, elastic and fluid flow properties of a fault zone immediately after rupture propagation, at the early stage of fault slip. While the physical mechanisms for pulverized rock generation are still not yet fully understood, it is likely that they are in some way related to a combination of the dynamic compressive and tensional stresses imparted on the rock surrounding a fault at the tip of a propagating earthquake rupture. Typical triaxial rock deformation apparatuses are limited by their loading systems to strain rates on the order of 10-4 s-1, which in terms of the seismic cycle, is only applicable to processes operating within the inter-seismic period. In order to achieve strain rates in excess of 100 s-1 under confined conditions with pore fluids (currently unachievable with conventional deformation apparatus such as split bar Hopkinson), we have designed, manufactured and constructed a new high strain rate triaxial rock deformation apparatus, with a unique innovative hydraulic loading system that allows samples to be deformed in compression and tension at strain rates from 10-7 up to 200 s-1 . We present preliminary data demonstrating the unique capability of this apparatus to produce co-seismic experimental conditions not previously acheived.

Process Control System of a 500-MW Unit of the Reftinskaya Local Hydroelectric Power Plant

International Nuclear Information System (INIS)

Grekhov, L. L.; Bilenko, V. A.; Derkach, N. N.; Galperina, A. I.; Strukov, A. P.

2002-01-01

The results of the installation of a process control system developed by the Interavtomatika Company (Moscow) for controlling a 500-MW pulverized coal power unit with the use of the Teleperm ME and OM650 equipment of the Siemens Company are described. The system provides a principally new level of automation and process control through monitors comparable with the operation of foreign counterparts with complete preservation of the domestic peripheral equipment. During the 4.5 years of operation of the process control system the intricate algorithms for control and data processing have proved their operational integrity

Identification and quantification of priority species from coal combustion

Energy Technology Data Exchange (ETDEWEB)

Furimsky, E.; Zheng, L.; Hlavacek, T. [Canada Centre for Mineral and Energy Technology, Ottawa, ON (Canada). Energy Research Laboratories

1996-07-01

The objective is to quantify and characterize emissions from pulverized coal combustion of seven coals and the circulating fluidized bed combustion of four coals. The species of particular interest are sulphur, nitrogen, chlorine, arsenic, mercury, lead, cadmium, potassium, and sodium. The Facility for Analysis of Chemical Thermodynamics (F{asterisk}A{asterisk}C{asterisk}T) method is used to predict type and amount of priority species. Prediction is made for combustion with and without the presence of limestone. The results show that the combustion technology used influences the amount of priority species emitted. 16 tabs., 3 apps.

Recycling of bagasse ash in cement manufacturing and its impact on clinker potential and environmental pollution

International Nuclear Information System (INIS)

Amin, N.U.; Ali, K.

2009-01-01

In this investigation bagasse ash from sugar mills of North West Frontier Province (NWFP) has been used in the raw mix designing for high strength Portland cement as a raw material and subjected to clinkerization and cement formation. Different parameters of the resulting clinker and cement were studied and compared with the British and Pakistan standard specification. 5% bagasse ash was found as the optimal limit to be blended and pulverized with other raw material prior to clinkerization which decreased the emission of carbon dioxide to the environment up to 1.73%. Moreover it replaced 5% clay from the raw meal. (author)

Laser scabbling for nuclear decommissioning: Effect of concrete composition on volume removal efficiency

International Nuclear Information System (INIS)

Peach, B.; Petkovski, M.; Blackburn, J.; Engelberg, D.L.

2015-01-01

The objective of this study was to determine the effect of concrete composition and moisture content on volume removal with the overarching goal to identify mechanism(s) responsible for laser scabbling. Tests under application of fixed laser parameters showed that concrete composition had a significant effect on material removal but the investigation into moisture content was inconclusive. The mechanical properties and size of coarse aggregates seemed to affect scabbling efficiency, rather than their chemical properties. The presence of pulverized fuel ash as a cement replacement material indicated to be a major factor that determines material removal volumes. (authors)

Food authenticity studies via multi-elemental and isotopic pattern using inductively coupled plasma mass spectrometry

International Nuclear Information System (INIS)

Katona, R.; Brunner, M.; Abranko, L.; Prohaska, T.; Stefanka, Z.

2009-01-01

Full text: The aim of our study has been the development of an analytical method based on Sr isotope and elemental fingerprint analysis for discriminating food samples from different geographical origin. Several types of foods were involved in the investigation representing different stages of food processing such as pulverized spicy paprika (sparsely processed food product) and wine samples (processed product). Independent inorganic mass spectrometric techniques like ICP-SFMS, ICP-CCMS, and MC-ICPMS were used for method validation and investigation of the geographical origin. The advantage and limitations of the developed methods are discussed critically. (author)

Morphological differences in coronary arteries following rotational atherectomy versus balloon angioplasty: ultrasound and angioscopic observations

Science.gov (United States)

Bass, Theodore A.; Gilmore, Paul S.; White, Christopher J.; Chami, Youssef G.; Kircher, Barbara J.; Conetta, Donald A.

1993-09-01

Percutaneous transluminal coronary rotational atherectomy (PTCRA) is an exciting new device to recannulate obstructed coronary arteries. This device works as a high speed `drill,' selectively cutting hard atherosclerotic plaque while preferentially sparing the softer, less diseased vascular luminal surface. At speeds as high as 200,000 rpm the plaque is pulverized into small particles easily handled by the circulatory system with no untoward clinical sequela. Balloon angioplasty does not remove atherosclerotic plaque. It dilates the vessel by mechanically stretching, compressing and splitting the plaque and vessel lining. We compare morphological and surface luminal characteristics of vessels post PTCRA to vessels post PTCA.

Irradiation damages in Ti3SiC2

International Nuclear Information System (INIS)

Nappe, J.C.; Grosseau, Ph.; Guilhot, B.; Audubert, F.; Beauvy, M.

2007-01-01

Carbides, by their remarkable properties, are considered as possible materials (fuel cans) in reactor of generation IV. Among those studied, Ti 3 SiC 2 is particularly considered because it joins both the ceramics and metals properties. Nevertheless, its behaviour under irradiation is not known. Characterizations have been carried out on samples irradiated at 75 MeV krypton ions. They have revealed that TiO 2 (formed at the surface of Ti 3 SiC 2 ) is pulverized by the irradiation and that the crystal lattice of Ti 3 SiC 2 dilates with c. (O.M.)

Seward CFB boilers will curb water pollution and air emissions

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-03-01

When Reliant Energy Co's Seward station begins commercial operation in 2004, it will replace an 80-yr-old pulverized-coal plant with a circulating fluidized bed (CFB) facility that more than doubles the capacity while slashing total air emissions. The baseload facility, located in Indiana County, PA, will be fuelled by local low-grade waste coal. Added to the back end of the two 292-MW CFB boilers, selective noncatalytic reduction equipment will lower NOx emissions, and ALSTOM's flash dryer absorber (FDA) system will lower SO{sub 2} emissions whilst using less limestone. 3 photos.

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...... to 575 degrees C and for the flue gas from 1025 to 1300 degrees C. All these test tubes have been removed during the last three years at one year intervals for corrosion studies. The corrosion studies performed on all investigated tubes included measurements of the corrosion attack, light optical...

Acoustic emission monitoring of activation behavior of LaNi5 hydrogen storage alloy

Directory of Open Access Journals (Sweden)

Igor Maria De Rosa, Alessandro Dell'Era, Mauro Pasquali, Carlo Santulli and Fabrizio Sarasini

2011-01-01

Full Text Available The acoustic emission technique is proposed for assessing the irreversible phenomena occurring during hydrogen absorption/desorption cycling in LaNi5. In particular, we have studied, through a parametric analysis of in situ detected signals, the correlation between acoustic emission (AE parameters and the processes occurring during the activation of an intermetallic compound. Decreases in the number and amplitude of AE signals suggest that pulverization due to hydrogen loading involves progressively smaller volumes of material as the number of cycles increases. This conclusion is confirmed by electron microscopy observations and particle size distribution measurements.

Measurement and modeling of advanced coal conversion processes, Volume II

Energy Technology Data Exchange (ETDEWEB)

Solomon, P.R.; Serio, M.A.; Hamblen, D.G. [and others

1993-06-01

A two dimensional, steady-state model for describing a variety of reactive and nonreactive flows, including pulverized coal combustion and gasification, is presented. The model, referred to as 93-PCGC-2 is applicable to cylindrical, axi-symmetric systems. Turbulence is accounted for in both the fluid mechanics equations and the combustion scheme. Radiation from gases, walls, and particles is taken into account using a discrete ordinates method. The particle phase is modeled in a lagrangian framework, such that mean paths of particle groups are followed. A new coal-general devolatilization submodel (FG-DVC) with coal swelling and char reactivity submodels has been added.

Retort for distilling oil from shales and other fuels

Energy Technology Data Exchange (ETDEWEB)

Wood, E C

1931-04-17

A retort is constructed in the form of a flat shallow covered conduit through which the fuel in a pulverized form is continuously conveyed on a train of pans so loaded as to completely fill the conduit, heat being applied to an adequate central portion of the conduit to effect the distillation of the fuel. The roof or cover is sufficiently higher for the extent of such heated portion to afford space for and thereby facilitate the offtake of the distillation products while the ends of the conduit remain sealed against the escape of such products.

Computation of 2-D pinhole image-formation process of large-scale furnaces using the discrete ordinates method

CERN Document Server

Li Hong; Lu Ji Dong; Zheng Chu Guan

2003-01-01

In most of the discrete ordinate schemes (DOS) reported in the literature, the discrete directions are fixed, and unable to be arbitrarily adjusted; therefore, it is difficult to employ these schemes to calculate the radiative energy image-formation of pulverized-coal furnaces. On the basis of a new DOS, named the discrete ordinate scheme with (an) infinitely small weight(s), which was recently proposed by the authors, a novel algorithm for computing the pinhole image-formation process is developed in this work. The performance of this algorithm is tested, and is found to be also suitable for parallel computation.

Computation of 2-D pinhole image-formation process of large-scale furnaces using the discrete ordinates method

International Nuclear Information System (INIS)

Li Hongshun; Zhou Huaichun; Lu Jidong; Zheng Chuguang

2003-01-01

In most of the discrete ordinate schemes (DOS) reported in the literature, the discrete directions are fixed, and unable to be arbitrarily adjusted; therefore, it is difficult to employ these schemes to calculate the radiative energy image-formation of pulverized-coal furnaces. On the basis of a new DOS, named the discrete ordinate scheme with (an) infinitely small weight(s), which was recently proposed by the authors, a novel algorithm for computing the pinhole image-formation process is developed in this work. The performance of this algorithm is tested, and is found to be also suitable for parallel computation

Use of coal-water mixtures in blast furnaces

Energy Technology Data Exchange (ETDEWEB)

Malgarini, G; Giuli, M; Davide, A; Carlesi, C [Centro Sviluppo Materiali, Rome (Italy); Italsider, Genoa [Italy; Deltasider, Piombino [Italy

1989-03-01

At the present time, an ironworks blast furnace employing a pulverized coal injection (PCI) system is in operation at the Piombino Works (Italy). A wide development, within this industry, of PCI techniques is expected in the near future to limit, as much as possible, the rebuilding of coke ovens. Research activities and industrial trials aimed at maximizing the use of coal injection into blast furnaces are in course of development. This paper uses flowsheets to illustrate such a system and provides graphs to indicate the economic convenience of PCI systems as compared with systems using naphtha as an injected fuel.

Mars - CO2 adsorption and capillary condensation on clays: Significance for volatile storage and atmospheric history

Science.gov (United States)

Fanale, F. P.; Cannon, W. A.

1979-01-01

Results on the adsorbate-adsorbent system CO2-nontronite are reported at 230, 196, and 158 deg K, covering the range of subsurface regolith temperature on Mars. A three-part regolith-atmosphere-cap model reveals that cold nontronite, and expanding clays in general, are far better but far more complex CO2 adsorbers than cold pulverized basalt. In addition, the layered terrain, and possibly the adjacent debris mantle, contains about 2% or more by mass of atmosphere-exchangeable CO2 and the total regolith inventory of available adsorbed CO2 is estimated to be 400 g/ sq cm.

Thermoluminescence studies on plant seeds of different radiosensitivity

International Nuclear Information System (INIS)

Yamaguchi, Hikoyuki; Eguchi, Hoshio; Koizumi, Yoshinobu.

1975-01-01

The thermoluminescence was found when the pulverized powders from the whole seeds of six plant species or the hypocotyls from the seeds of five soybean varieties were irradiated at a liquid nitrogen temperature with gamma-rays. The spectra of luminescence emitted, the light peak temperature, the decaying after irradiation and the dose relationship of luminescence were determined. A high yield of the rapidly-decaying luminescence occurred in the more radiosensitive variety when irradiated with relatively lower doses. The very drastic decrease of the thermoluminescence was observed in the samples irradiated at room temperature prior to the exposure at 77 0 K. (auth.)

Neutron activation analysis of trace metals in the livers of Japanese sika deer (cervus Nippon)

International Nuclear Information System (INIS)

Fukushima, Michiko; Tamate, Hidetoshi; Sasaki, Yoshiro; Mitsugasira, Satoaki; Masumoto, Kazuyoshi.

1997-01-01

Neutron activation analysis facilities at the JMTR reactor was used to determine the levels of trace metals in the livers of nine Japanese sika deer. The samples were cut into pieces, pulverized in liquid nitrogen, freeze-dried, and finally fractionated through a stainless steel sieve of 200 mesh. Then the samples were irradiated for 6 or 24 hours by a neutron flux of 1.0x10 14 n·cm -2 ·sec -1 . In the present work, we analysed the concentrations of six elements (Ag, Co, Fe, Rb, Se, and Zn) in the livers of nine deer. (author)

Recovery of iron oxide from coal fly ash

Science.gov (United States)

Dobbins, Michael S.; Murtha, Marlyn J.

1983-05-31

A high quality iron oxide concentrate, suitable as a feed for blast and electric reduction furnaces is recovered from pulverized coal fly ash. The magnetic portion of the fly ash is separated and treated with a hot strong alkali solution which dissolves most of the silica and alumina in the fly ash, leaving a solid residue and forming a precipitate which is an acid soluble salt of aluminosilicate hydrate. The residue and precipitate are then treated with a strong mineral acid to dissolve the precipitate leaving a solid residue containing at least 90 weight percent iron oxide.

TRISO-coated spent fuel processing using a Grind-Leach head-end

International Nuclear Information System (INIS)

Spencer, Barry B.; Del Cul, Guillermo D.; Mattus, Catherine H.; Collins, Emory D.

2005-01-01

Processing of TRISO-coated HTGR fuels with the grind-leach process requires that the fuel be finely pulverized for efficient and effective acid dissolution of the fuel components. Mechanical size reduction of the fuel is being investigated with jet mill technology as the final milling step. Laboratory experiments were performed with surrogates of crushed fuel compacts that indicate that milling to very small particle sizes is feasible. The size distribution of the milled product is sensitive to the solids feed rate, and the distribution may be bimodal which could support an effective solid-solid separation. (author)

Powder metallurgical processing of magnetostrictive materials based on rare earth-iron intermetallic compounds

International Nuclear Information System (INIS)

Malekzadeh, M.

1978-01-01

Procedures are described for fabrication of high density rare earth-iron magnetostrictive compounds by powder metallurgical techniques. The fabrication involves a sequence of steps which includes preparing the pre-alloyed compounds, pulverizing them into a fine powder, compacting in suitable sizes and shapes, and sintering. Samples prepared by these procedures are carefully characterized by scanning electron microscopy, x-ray diffraction, dilatometry, and magnetic measurements. Process steps are found to exert important influences upon densities, microstructure and magnetic properties attained after densification. Investigations on a number of these process steps, including milling time and medium, sintering, and magnetic powder alignment are described

Design and development of an Integrated Slasher (Pulverizer) for Sweet Potato Harvester: A Review

International Nuclear Information System (INIS)

Kakahy, Amer N N; Ahmad, D; Akhir, M D; Ishak, A; Sulaiman, S

2012-01-01

In this study information on the development of combined sweet potato harvester is presented. The study focuses on the design, manufacture and choice of the best slasher for cutting and fragmentation of stems and leaves (vegetative portion) for the crop to facilitate the process of harvesting and extraction of tubers. A survey on various types and forms of cutters (mowers) and knives normally used for cutting vines and leaves was conducted and concluded that the vertical type and flail type mowers are the most effective in removing of the vegetative growth. In addition there is a need to design an integrated harvester, which combines both the cutting and digging in a single pass in order to reduce the time taken for harvesting, the fuel consumption and the number of machines used since this will give some economical advantages. In addition to the design requirements, it is recommended that number of tests should be conducted to select the suitable speed for the tractor, the velocity for cutters and the length of knives for both sides of the ridges to avoid damage to the tubers.

Sotsiaalteaduskond 1993-2007 / Kristel Marmor ; meenutavad Aleksander Pulver, Jüri Kruusvall ja Arno Baltin

Index Scriptorium Estoniae

Marmor, Kristel

2008-01-01

11. jaanuaril 2008. aastal tähistas sotsiaalteaduskond oma 15. tegevusaastat ja samas ka matust. Meenutused psühholoogiaprofessor Aleksander Pulverilt, sotsioloogia vanemteadurilt Jüri Kruusvallilt ning matusekõne Arno Baltinilt

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

DEFF Research Database (Denmark)

Saastamoinen, Jaakko; Aho, Martti; Moilanen, Antero

2010-01-01

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

Toomas Hendrik Ilves külastas Lääne-Virumaad / Teet Suur, Andres Pulver

Index Scriptorium Estoniae

Suur, Teet

2008-01-01

President Toomas Hendrik Ilves külastas 5. novembril 2008 Kirde kaitseringkonna Tapa sõjaväelinnakut, tutvus Kellavere radari tööga ja kohtus Lääne-Viru maleva kaitseliitlastega. Lõunatamas käis president Rakvere veekeskuse restoranis Mezzo. Riigipea on viimase aasta jooksul külastanud Kaitseliidu 13 malevat. Juuresoleval fotol president koos Kaitseliidu Lääne-Viru maleva pealiku kapten Lembit Kervega

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

DEFF Research Database (Denmark)

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

2012-01-01

Several measuring campaigns with focus on deposition behavior have been conducted at full-scale power plants firing biomass in Denmark. These campaigns have been reviewed in this work. The focus is the obtained experiences on deposit formation, shedding and chemistry. When comparing results from...

Pyrite thermochemistry, ash agglomeration, and char fragmentation during pulverized coal combustion. Final technical report

Energy Technology Data Exchange (ETDEWEB)

Akan-Etuk, A.; Diaz, R.; Niksa, S.

1991-10-01

The objective of the present work is to introduce an experimental program that will eventually lead to time-resolved iron ash composition over the technological operating domain. The preceding literature survey suggests two important stipulations on any such experimental program. The first stipulation is that good control must be established over the operating conditions, to accurately quantify their effects. The other is that data must be obtained rapidly, to thoroughly cover the important operating domain. This work presents a series of studies that has characterized the desulfurization of pyrite during the early stages of combustion. An experimental system was established and used to monitor the effects of oxygen, temperature, and residence time on the evolution of condensed phase products of the combustion of pure pyrite. (VC)

Thin films of preparation SnOx by evaporation and pulverization reactive in vapor phase

International Nuclear Information System (INIS)

Solis, J.; Estrada, W.; Soares, M.; Schreiner, W.

1993-01-01

In this work we obtained SnO x thin films by reactive evaporation. The structure and composition of the films were characterized by x-ray diffraction and Moessbauer spectroscopy. The samples as deposited present different kind of microstructures depending on the parameters deposition, such as substrate temperature and oxygen pressure. In general the samples present three pushes: Sn, SnO and SnO 2 . When the samples are subjected to heat treatment, the as deposited SnO x finally converts to SnO 2 . (authors) 10 refs., 4 figs

The Basic Research for Pulverization of Rice Using Underwater Shock Wave by Electric Discharge

Directory of Open Access Journals (Sweden)

M Ide

2016-09-01

Full Text Available In recent years, the food self-support rate of Japan is 40%, and this value is the lowest level in major developed countries. This reason includes decreasing of diverting rice consumption in Japan and increasing abandonment of cultivation. Therefore, these problems are solved by using rice powder instead of expensive flour, and we manage to increase the food selfsupport rate. Previously, the rice powder is manufactured by two methods. One is dry type, and the other is wet type. The former is the method getting rice powder by running dried rice to rotating metal, and has a problem which that starch is damaged by heat when processing was performed. The latter is performed same method against wet rice, and has a problem which a large quantity of water is used. As a method to solve these problems, an underwater shock wave is used. Shock wave is the pressure wave which is over speed of sound by discharging high energy in short time. Propagating shock wave in water is underwater shock wave. The characters of underwater shock wave are long duration of shock wave because water density is uniform, water is low price and easy to get and not heat processing. Thinking of industrialization, the electric discharge is used as the generating source of underwater shock wave in the experiment. As the results, the efficiency of obtaining enough grain size, 100ìm, of rice powder was too bad only using the simple processing using underwater shock wave. Therefore, in Okinawa National College of Technology collaborating with us, obtaining rice powder with higher efficiency by using converged underwater shock wave is the goal of this research. In this research, the underwater shock wave with equal energy of the experimental device of underwater shock wave is measured by the optical observation. In addition, the appearance converging underwater shock wave is simulated by numerical analysis, and the pressure appreciation rate between the first wave and converged underwater shock wave is calculated by using the pressure history of 2nd focal point.

Upgraded fuel from reed canary grass

Energy Technology Data Exchange (ETDEWEB)

Heiskanen, V.P.

1995-12-31

The feasibility of RCG for commercial utilization depends primarily on its applicability for pulp production and its use in energy production will be based on the residue that will be available after extracting the pulp fraction of the RCG. Roughly 20 ..30% of the material will be available for energy production purposes. However, the percentage may be higher/lower depending on the quality standards of the pulp fiber material. The harvesting period has a significant effect on the fuel characteristics of RCG. For instance the contents of N, S, Cl, K are clearly lower if the RCG is harvested in the spring (delayed) instead of summer/autumn. These elements affect significantly overall emission formation and ash behaviour and its melting temperature. The combustion related research in this project has been focused on the spring-harvested RCG. The project aims to evaluate the feasibility of delayed harvested RCG for energy production. In order to reach this goal, the following combustion methods will be tested and studied: combustion of pelletized RCG; gasification; combustion of pulverized RCG. In addition, pelletizing, reactivity and NO conversion of pulverized RCG will be studied. The research described here is a part of `Reed Canary Grass` project (in AIR programme). The contractors of the project are Swedish University of Agricultural Sciences (coordinator), United Milling Systems from Denmark, Jaakko Poeyry Oy and VTT Energy. In addition, there are partners from several countries participating in the project. The project has been divided in five tasks, VTT Energy being responsible for combustion related task `Upgraded fuel` that includes the research topics discussed in this paper

Upgraded fuel from reed canary grass

Energy Technology Data Exchange (ETDEWEB)

Heiskanen, V P

1996-12-31

The feasibility of RCG for commercial utilization depends primarily on its applicability for pulp production and its use in energy production will be based on the residue that will be available after extracting the pulp fraction of the RCG. Roughly 20 ..30% of the material will be available for energy production purposes. However, the percentage may be higher/lower depending on the quality standards of the pulp fiber material. The harvesting period has a significant effect on the fuel characteristics of RCG. For instance the contents of N, S, Cl, K are clearly lower if the RCG is harvested in the spring (delayed) instead of summer/autumn. These elements affect significantly overall emission formation and ash behaviour and its melting temperature. The combustion related research in this project has been focused on the spring-harvested RCG. The project aims to evaluate the feasibility of delayed harvested RCG for energy production. In order to reach this goal, the following combustion methods will be tested and studied: combustion of pelletized RCG; gasification; combustion of pulverized RCG. In addition, pelletizing, reactivity and NO conversion of pulverized RCG will be studied. The research described here is a part of `Reed Canary Grass` project (in AIR programme). The contractors of the project are Swedish University of Agricultural Sciences (coordinator), United Milling Systems from Denmark, Jaakko Poeyry Oy and VTT Energy. In addition, there are partners from several countries participating in the project. The project has been divided in five tasks, VTT Energy being responsible for combustion related task `Upgraded fuel` that includes the research topics discussed in this paper

Study of the microstructural and mechanical properties of titanium-niobium-zirconium based alloys processed with hydrogen and powder metallurgy for use in dental implants; Estudo das propriedades mecanicas e microestruturais de ligas a base de titanio-niobiozirconio processados com hidrogenio e metalurgia do po para utilizacao em implantes dentarios

Energy Technology Data Exchange (ETDEWEB)

Duvaizem, Jose Helio

2009-07-01

Hydrogen has been used as pulverization agent in alloys based on rare earth and transition metals due to its extremely high diffusion rate even on low temperatures. Such materials are used on hydrogen storage dispositives, generation of electricity or magnetic fields, and are produced by a process which the first step is the transformation of the alloy in fine powder by miling. Besides those, hydrogenium is also being used to obtain alloys based on titanium - niobium - zirconium in the pulverization. Powder metallurgy is utilized on the production of these alloys, making it possible to obtain structures with porous surface as result, requirement for its application as biomaterials. Other advantages of powder metallurgy usage include better surface finish and better microstructural homogeneity. In this work samples were prepared in the Ti-13Nb-13Zr composition. The hydrogenation was performed at 700 degree C, 600 degree C, and 500 degree C for titanium, niobium and zirconium respectively. After hydrogenation, the milling stage was carried out on high energy planetary ball milling with 200rpm during 90 minutes, and also in conventional ball milling for 30 hours. Samples were pressed in uniaxial press, followed by isostatic cold press, and then sintered at 1150 degree C for 7-13 hours. Microstructural properties of the samples were characterized by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and x-ray diffraction. Mechanical and structural properties determined were density, microhardness and moduli of elasticity. The sample sintered at 1150 degree C for 7h, hydrogenated using 10.000 mbar and produced by milling on high energy planetary ball milling presented the best mechanical properties and microstructural homogeneity. (author)

Study of the microstructural and mechanical properties of titanium-niobium-zirconium based alloys processed with hydrogen and powder metallurgy for use in dental implants

International Nuclear Information System (INIS)

Duvaizem, Jose Helio

2009-01-01

Hydrogen has been used as pulverization agent in alloys based on rare earth and transition metals due to its extremely high diffusion rate even on low temperatures. Such materials are used on hydrogen storage dispositives, generation of electricity or magnetic fields, and are produced by a process which the first step is the transformation of the alloy in fine powder by miling. Besides those, hydrogenium is also being used to obtain alloys based on titanium - niobium - zirconium in the pulverization. Powder metallurgy is utilized on the production of these alloys, making it possible to obtain structures with porous surface as result, requirement for its application as biomaterials. Other advantages of powder metallurgy usage include better surface finish and better microstructural homogeneity. In this work samples were prepared in the Ti-13Nb-13Zr composition. The hydrogenation was performed at 700 degree C, 600 degree C, and 500 degree C for titanium, niobium and zirconium respectively. After hydrogenation, the milling stage was carried out on high energy planetary ball milling with 200rpm during 90 minutes, and also in conventional ball milling for 30 hours. Samples were pressed in uniaxial press, followed by isostatic cold press, and then sintered at 1150 degree C for 7-13 hours. Microstructural properties of the samples were characterized by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and x-ray diffraction. Mechanical and structural properties determined were density, microhardness and moduli of elasticity. The sample sintered at 1150 degree C for 7h, hydrogenated using 10.000 mbar and produced by milling on high energy planetary ball milling presented the best mechanical properties and microstructural homogeneity. (author)

Thermal analysis evaluation of the reactivity of coal mixtures for injection in the blast furnace

Directory of Open Access Journals (Sweden)

Maria de Lourdes Ilha Gomes

2006-03-01

Full Text Available Pulverized Coal Injection (PCI is an important standard technology replacing coke partially by pulverized coal into the blast furnace that allows a significant reduction of hot metal costs and environmental impact, contributing to a decrease of coke requirements for ironmaking. Coals typically used in this process in Brazil are, at current time, exclusively imported from many countries, although economic important coal-measures occur in the southern part of the country. The Brazilian coals have a low rank, higher contents of inert components, proportioning nocoking properties and an expected high reactivity. Due to these caractheristics, these coals could be used for injection in the blast furnaces in order to decrease the dependency on high cost imported coals. The efficiency in the combustion and the coal reactivity are considered important parameters in the blast furnace, since a larger amount of char (unburned coal causes severe problems to the furnace operation. The aim of the present work is to compare the reactivity of a south Brazilian coal, obtained from Faxinal mine, with two imported coals and the blends of the Brazilian coal with the imported ones. The reactivity of these coals and their blends were evaluated in a thermogravimetric analyzer. In the experiments, various mass ratios of Faxinal coal and the imported coals were used to compose the blends. The gasification reaction with pure CO2 was conducted under isothermal conditions at 1050 °C and atmospheric pressure. The experimental results show the greater reactivity of the Faxinal coal. The additive behavior was confirmed. The blends with a composition of up to 50% Faxinal coal have parameters according to the usual limits used for PCI.

Firing in fluid beds and burners

Energy Technology Data Exchange (ETDEWEB)

Frandsen, F.; Lans, R. van der; Storm Pedersen, L.; Philbert Nielsen, H.; Aslaug Hansen, L.; Lin, W.; Johnsson, J.E.; Dam-Johansen, K.

1998-02-01

An investigation of the effect of co-firing straw and pulverized coal was performed. Based on experiments from pilot-scale and full-scale it was concluded that a higher fraction of straw in the fuel feedstock mixture results in lower NO and SO{sub 2} emissions. The lower NO emission was mainly due to the higher volatile content of the straw, which leads to lower stoichiometry in the gas phase and in subsequent suppression of NO{sub x} formation. This conclusion is consistent with experimental and modeling results for pure coal combustion. The effect of coal quality on NO emissions has been investigated with three coals of different characteristics in three furnaces: in the Funen power station, unit 7 (FVO7), the Midtkraft Studstrup power station, unit 4 (MKS4), and the Mitsui Babcock Energy Ltd (MBEL) test-rig. The MBEL test-rig was able to reproduce qualitatively the emissions from the MKS4 plant, and quantitatively the emissions from the FVO7 plant. The better agreement between the MBEL test-rig and FVO7 is presumed to be related to the existence of a large primary zone with a relatively low stoichiometry, diminishing the influence of near burner air and fuel mixing rate on the NO emissions. An engineering model has been developed for the prediction of NO emissions and burnout from pulverized fuel combustion in swirl burners. A simplified model for reduction of N{sub 2}O in CFBC has been developed, and simulation results are in good agreement with experimental data from a 12 MW{sub th} CFB-boiler. (EG) EFP-94. 108 refs.

Injection of natural gas in the blast furnace tuyeres three of the Usiminas, Ipatinga Plant; Injecao de gas natural nas ventaneiras do alto-forno 3 da Usiminas, Usina de Ipatinga

Energy Technology Data Exchange (ETDEWEB)

Souza, Murilo Alves Tito de; Rosa, Ericson Rimen Ribeiro; Oliveira, Claudiney Freitas de; Hostt, Helton [USIMINAS, Ipatinga, MG (Brazil). Gerencia Geral de Reducao

2011-12-21

The reduction in production costs is a major strategic objectives of Usiminas and the use of natural gas in the Blast Furnace 3 (BF 3) contribute to achieve this goal. The use of natural gas as fuel in the BF 3 to reduce the use of metallurgical coke (main fuel) and reduces production losses during periods of maintenance in the pulverized coal injection system and improving operational control of the Blast Furnace. The work presents the deployment of the natural gas injection and the performance obtained by the BF 3 from the start of injection, with a focus on reducing consumption of metallurgical coke and stable operation of blast furnace (author)

Economic comparison of clean coal generating technologies with natural gas-combined cycle systems

International Nuclear Information System (INIS)

Sebesta, J.J.; Hoskins, W.W.

1990-01-01

This paper reports that there are four combustion technologies upon which U.S. electric utilities are expected to rely for the majority of their future power generating needs. These technologies are pulverized coal- fired combustion (PC); coal-fired fluidized bed combustion (AFBC); coal gasification, combined cycle systems (CGCC); and natural gas-fired combined cycle systems (NGCC). The engineering and economic parameters which affect the choice of a technology include capital costs, operating and maintenance costs, fuel costs, construction schedule, process risk, environmental and site impacts, fuel efficiency and flexibility, plant availability, capacity factors, timing of startup, and the importance of utility economic and financial factors

Towards a better understanding of biomass suspension co-firing impacts via investigating a coal flame and a biomass flame in a swirl-stabilized burner flow reactor under same conditions

DEFF Research Database (Denmark)

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

2012-01-01

increases the residence time of coal particles. Both the factors favor a complete burnout of the coal particles. The higher volatile yields of the straw produce more off-gas, requiring more O2 for the fast gas phase combustion and causing the off-gas to proceed to a much larger volume in the reactor prior...... to mixing with oxidizer. For the pulverized straw particles of a few hundred microns in diameters, the intra-particle conversion is found to be a secondary issue at most in their combustion. The simulations also show that a simple switch of the straw injection mode can not improve the burnout of the straw...

Technical notes for the conceptual design for an atmospheric fluidized-bed direct combustion power generating plant. [570 MWe plant

Energy Technology Data Exchange (ETDEWEB)

None

1978-04-01

The design, arrangement, thermodynamics, and economics of a 592 MW(e) (nominal gross) electric power generating plant equipped with a Babcock and Wilcox Company (B and W) atmospheric fluidized bed (AFB) boiler are described. Information is included on capital and operating costs, process systems, electrical systems, control and instrumentation, and environmental systems. This document represents a portion of an overall report describing the conceptual designs of two atmospheric fluidized bed boilers and balance of plants for the generation of electric power and the analysis and comparison of these conceptual designs to a conventional pulverized coal-fired electric power generation plant equipped with a wet limestone flue gas desulfurization system.

Metal concentrations in scleractinean corals determined by instrumental neutron activation analysis and atomic absorption spectrometry

International Nuclear Information System (INIS)

Gomez Saunders, M.; Montero Cabrera, M.E.; Herrera Peraza, E.F.; Castellon Insua, L.; Gonzalez Labrada, K.; Lopez Reyes, M.C.

1997-01-01

Five species of scleractinean corals, extracted from the Northern Havana reef, were studied by INAA and AAS. Selected specimens were sectioned in 'foot', 'enter' and 'head' parts before pulverization procedure. INAA for different irradiation and decay time regimes in a reactor allowed the determination of: Na, Mg, Al, Cl, Sc, Cr, Co, Th, Lu, Eu, Ce, Hf, La and Sr. AAS was performed in a Pye Unicam Model 929 spectrometer. Cu, Mn, Ni, Zn, and Fe were detected. Ca concentration in all species was also established. Obtained Metal-Calcium ratios for Sr, Cu, Zn, Cr, Co, Fe, Mn, Ni and Sc are compared with reported values. (author)

Irradiation damages in Ti{sub 3}SiC{sub 2}; Dommages d'irradiation dans Ti{sub 3}SiC{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Nappe, J.C.; Grosseau, Ph. [Ecole Nationale Superieure des Mines, Centre SPIN, Lab. PMMC et LPMG UMR CNRS 5148, 42 - Saint-Etienne (France); Guilhot, B. [Ecole Nationale Superieure des Mines, Centre CIS, 42 - Saint-Etienne (France); Audubert, F.; Beauvy, M. [CEA Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. d' Etudes des Combustibles; Iacconi, Ph.; Benabdesselam, M. [Nice Univ. - Sophia Antipolis, Lab. LPES-CRESA, 06 (France)

2007-07-01

Carbides, by their remarkable properties, are considered as possible materials (fuel cans) in reactor of generation IV. Among those studied, Ti{sub 3}SiC{sub 2} is particularly considered because it joins both the ceramics and metals properties. Nevertheless, its behaviour under irradiation is not known. Characterizations have been carried out on samples irradiated at 75 MeV krypton ions. They have revealed that TiO{sub 2} (formed at the surface of Ti{sub 3}SiC{sub 2}) is pulverized by the irradiation and that the crystal lattice of Ti{sub 3}SiC{sub 2} dilates with c. (O.M.)