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Sample records for kiln dust

  1. potentials of cement kiln dust in sub-grade improvement

    African Journals Online (AJOL)

    2013-03-01

    Mar 1, 2013 ... alternative uses of waste materials in different geotech- nical application including .... tained in bags and stored in air tight containers. The. CKD was ... Figure 5: Variation of plastic limit with cement kiln dust. Figure 6: Variation ...

  2. CEMENT KILN DUST AS A MATERIAL FOR BUILDING BLOCKS ...

    African Journals Online (AJOL)

    This paper presents the results of a study on the properties of hollow sandcrete blocks with cement kiln dust (CKD) as an additive and as a replacement for ordinary portland cement (OPC). When CKD was used as a replacement for cement, the compressive strength and density of blocks generally decreased with higher ...

  3. Improvement of poor subgrade soils using cement kiln dust

    Directory of Open Access Journals (Sweden)

    Ahmed Mancy Mosa

    2017-12-01

    Full Text Available Construction of pavements layers on subgrade with excellent to good properties reduces the thickness of the layers and consequently reduces the initial and maintenance cost of highways and vice versa. However, construction of pavements on poor subgrade is unavoidable due to several constrains. Improvement of subgrade properties using traditional additives such as lime and Portland cement adds supplementary costs. Therefore, using by-products in this domain involves technical, economic, and environmental advantages. Cement kiln dust (CKD is generated in huge quantities as a by-product material in Portland cement plants. Therefore, it can be considered as an excellent alternative in this domain. In Iraq, Portland cement plants generate about 350000 tons of CKD annually which is available for free. Therefore, Iraq can be adopted as a case study. This paper covers using CKD to improve the properties of poor subgrade soils based on series of California Bearing Ration (CBR tests on sets of untreated samples and samples treated with different doses of CKD in combination with different curing periods to investigate their effects on soil properties. The results exhibited that adding 20% of CKD with curing for 14 days increases the CBR value from 3.4% for untreated soil to 48% for treated soil; it, also, decreases the swelling ratio. To determine the effects of using this dose under the mentioned curing period on the designed thicknesses of pavements layers, a case study was adopted. The case study results exhibited that treatment of the subgrade soil by 20% of CKD with curing for 14 days reduces the cost of the pavements by $25.875 per square meter.

  4. Mechanism and Modelling for Sorption of Toxic Ion on Cement Kiln Dust

    International Nuclear Information System (INIS)

    EI- Dakroury, A.; Sayed, M.S.; EL- Sherif, E.

    2009-01-01

    Cement manufacturing is a critically important industry in Egypt. These industrial by-product and waste materials must be managed responsibly to insure a clean and safe environment. Cement kiln dust (CKD) is a significant by-product material of the cement manufacturing process. Cement kiln dust is a waste residue composed chiefly of oxidized, anhydrous, micron - sized particles generated as a by product of the manufacture of Portland cement. The use of cement kiln dust as adsorbent in wastewater treatment has a great attention as cheap material and clay structure. This work will discuss the basic characteristics of CKD physical and chemical properties and regulatory requirements: The batch removal of Cr(VI) from aqueous solution using low cost adsorbents such as cement kiln dust under different experimental conditions. The influences of initial Cr (VI) ion concentration (20 to 300 mg1-1) and ph (1 to 4) were investigated in this study. Adsorption of Cr (VI) is highly ph-dependent and the results indicate that the optimum ph for the removal was found to be 1 for CKD. A comparison of kinetic models applied to the adsorption of Cr (VI) ions on the CKD was evaluated for the pseudo first order, the pseudo second-order, Elovich and intra particle diffusion kinetic models, respectively. The results showed that the pseudo second-order kinetic model was found to correlate the experimental data well

  5. Lime kiln dust as a potential raw material in portland cement manufacturing

    Science.gov (United States)

    Miller, M. Michael; Callaghan, Robert M.

    2004-01-01

    In the United States, the manufacture of portland cement involves burning in a rotary kiln a finely ground proportional mix of raw materials. The raw material mix provides the required chemical combination of calcium, silicon, aluminum, iron, and small amounts of other ingredients. The majority of calcium is supplied in the form of calcium carbonate usually from limestone. Other sources including waste materials or byproducts from other industries can be used to supply calcium (or lime, CaO), provided they have sufficiently high CaO content, have low magnesia content (less than 5 percent), and are competitive with limestone in terms of cost and adequacy of supply. In the United States, the lime industry produces large amounts of lime kiln dust (LKD), which is collected by dust control systems. This LKD may be a supplemental source of calcium for cement plants, if the lime and cement plants are located near enough to each other to make the arrangement economical.

  6. Mechanical properties of Self-Consolidating Concrete incorporating Cement Kiln Dust

    OpenAIRE

    El-Mohsen, Mostafa Abd; Anwar, Ahmed M.; Adam, Ihab A.

    2015-01-01

    Self-Consolidating Concrete (SCC) has been widely used in both practical and laboratory applications. Selection of its components and their ratios depends, mainly, on the target mechanical and physical properties recommended by the project consultant. Partial replacement of cement in SCC with cheap available industrial by-product could produce environmentally durable concrete with similar properties of normal concrete. In the current research, SCC was produced by blending Cement Kiln Dust (CK...

  7. Energy conservation and dust production in wet rotary cement kilns

    Energy Technology Data Exchange (ETDEWEB)

    Sell, N J; Fischbach, F A

    1976-12-01

    Energy conservation is currently a major concern of the cement industry. A comparison of data supplied by the U.S. Federal Energy Administration with that gathered in an extensive private study incorporating 29 wet cement plants indicates that a significant reduction of the energy consumed can be accomplished by decreasing the amount of dust generated in the process. Energy saving of 8 percent through dust suppression appears possible by increasing the slurry moisture and by using hammermills rather than impactors as the crushing technique.

  8. 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 ...

  9. Mechanical properties of Self-Consolidating Concrete incorporating Cement Kiln Dust

    Directory of Open Access Journals (Sweden)

    Mostafa Abd El-Mohsen

    2015-04-01

    Full Text Available Self-Consolidating Concrete (SCC has been widely used in both practical and laboratory applications. Selection of its components and their ratios depends, mainly, on the target mechanical and physical properties recommended by the project consultant. Partial replacement of cement in SCC with cheap available industrial by-product could produce environmentally durable concrete with similar properties of normal concrete. In the current research, SCC was produced by blending Cement Kiln Dust (CKD with cement in different ratios. Four mixes incorporating cement kiln dust with partial cement replacement of 10%, 20%, 30%, and 40% were produced and compared with a control mix of Normally Vibrated Concrete (NVC. Superplasticizer was used to increase the flow-ability of SCC mixes. The fresh and hardened mechanical properties of all mixes were determined and evaluated. Moreover, time-dependent behavior was investigated for all mixes in terms of drying shrinkage test. The shrinkage strain was measured for all specimens for a period of 120 days. Based on the experimental results, it was found that SCC mixture containing 20% cement replacement of CKD exhibited the highest mechanical strength compared to other SCC mixes and NVC mix as well. It was observed that the volumetric changes of specimens were directly proportional to the increase of the cement replacement ratio.

  10. New Medium for Isolation of Bacteria From Cement Kiln Dust with a Potential to Apply in Bio-Concrete

    Science.gov (United States)

    Alshalif, A. F.; Irwan, J. M.; Othman, N.; Al-Gheethi, A.

    2018-04-01

    The present study aimed to introduce a new isolation medium named kiln dust medium (KDM) for recovering of bacteria from cement kiln dust with high pH (>pH 11) without the need for nutrients additives. The cement kiln dust samples were collected from five different areas of Cement Industries of Malaysia Berhad (CIMA). The bacterial isolates were recovered on KDM by direct plating technique. The chemical components for all collected samples were identified using X-ray fluorescence (XRF). The primary identification for the bacterial isolates indicated that these bacteria belongs to Bacillus spp. Based on the morphological characteristics. The growth curve of the bacterial strains was monitored using the optical density (OD) with 650 nm wavelength, which in role confirmed that all isolated bacteria had the ability to grow successfully in the proposed medium. The ability of the bacterial strains to grow at high pH reflects their potential in the bio-concrete applications (aerated and non-aerated concrete). These findings indicated that the cement kiln dust samples from Cement Industries represent the most appropriate source for bacteria used in the bioconcrete.

  11. Reuse of Cement Kiln Dust for backfilling and CO2 carbonation

    Directory of Open Access Journals (Sweden)

    Lutyński Marcin

    2017-01-01

    Full Text Available The study aims to investigate possible alternative paths of reusing Cement Kiln Dust in mining technologies or as mineral sorbent for CO2 capture. Properties of CKD and bottom slag slurry were assessed and these were ia.: chemical composition, compressive strength and excess water content. Results show that CKD/bottom slag slurry mixed in the proportion of 25%/75% can be used as a backfill material if concentration of contaminants in the leaching tests is at the acceptable level. Second part of the study was devoted to the assessment of CKD as a sorbent in Calcium looping technologies or for mineral carbonation. TGA and DSC study shows that the rate of CO2 capture (carbonation is determined by the free CaO content. The highest carbonation rate was within the temperature range of 600-800°C.

  12. Feasibility of backfilling mines using cement kiln dust, fly ash, and cement blends

    Directory of Open Access Journals (Sweden)

    Beltagui H.

    2018-01-01

    Full Text Available 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 strength un-reinforced applications. One potential application involves the backfill of mines, reducing the need for continuous maintenance of the mine. This study focuses on the compressive strength achieved by various blends of CKD, PFA, and cement. Samples were hand mixed and compacted in 100 mm x 50 mm diameter cylinders, and unconfined compressive strength measurements taken at 28 and 56 days. The hydration products were assessed through the use of x-ray diffraction and thermogravimetric analysis. Aiming to maximise the use of CKD at a water to binder (w/b ratio of 0.2, it was found that the maximum CKD content possible to achieve the required strength was 90% CKD blended with 10% cement.

  13. Stabilization/solidification of selenium-impacted soils using Portland cement and cement kiln dust

    International Nuclear Information System (INIS)

    Moon, Deok Hyun; Grubb, Dennis G.; Reilly, Trevor L.

    2009-01-01

    Stabilization/solidification (S/S) processes were utilized to immobilize selenium (Se) as selenite (SeO 3 2- ) and selenate (SeO 4 2- ). Artificially contaminated soils were prepared by individually spiking kaolinite, montmorillonite and dredged material (DM; an organic silt) with 1000 mg/kg of each selenium compound. After mellowing for 7 days, the Se-impacted soils were each stabilized with 5, 10 and 15% Type I/II Portland cement (P) and cement kiln dust (C) and then were cured for 7 and 28 days. The toxicity characteristic leaching procedure (TCLP) was used to evaluate the effectiveness of the S/S treatments. At 28 days curing, P doses of 10 and 15% produced five out of six TCLP-Se(IV) concentrations below 10 mg/L, whereas only the 15% C in DM had a TCLP-Se(IV) concentration 3 .H 2 O) and selenate substituted ettringite (Ca 6 Al 2 (SeO 4 ) 3 (OH) 12 .26H 2 O), respectively.

  14. Stabilization/solidification of selenium-impacted soils using Portland cement and cement kiln dust.

    Science.gov (United States)

    Moon, Deok Hyun; Grubb, Dennis G; Reilly, Trevor L

    2009-09-15

    Stabilization/solidification (S/S) processes were utilized to immobilize selenium (Se) as selenite (SeO(3)(2-)) and selenate (SeO(4)(2-)). Artificially contaminated soils were prepared by individually spiking kaolinite, montmorillonite and dredged material (DM; an organic silt) with 1000 mg/kg of each selenium compound. After mellowing for 7 days, the Se-impacted soils were each stabilized with 5, 10 and 15% Type I/II Portland cement (P) and cement kiln dust (C) and then were cured for 7 and 28 days. The toxicity characteristic leaching procedure (TCLP) was used to evaluate the effectiveness of the S/S treatments. At 28 days curing, P doses of 10 and 15% produced five out of six TCLP-Se(IV) concentrations below 10mg/L, whereas only the 15% C in DM had a TCLP-Se(IV) concentration soil-cement slurries aged for 30 days enabled the identification of Se precipitates by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX). XRD and SEM-EDX analyses of the Se(IV)- and Se(VI)-soil-cement slurries revealed that the key selenium bearing phases for all three soil-cement slurries were calcium selenite hydrate (CaSeO(3).H(2)O) and selenate substituted ettringite (Ca(6)Al(2)(SeO(4))(3)(OH)(12).26H(2)O), respectively.

  15. Improvement of geotechnical properties of sabkha soil utilizing cement kiln dust

    Directory of Open Access Journals (Sweden)

    Abdullah A. Al-Homidy

    2017-08-01

    Full Text Available Improvement of properties of weak soils in terms of strength, durability and cost is the key from engineering point of view. The weak soils could be stabilized using mechanical and/or chemical methods. Agents added during chemical stabilization could improve the engineering properties of treated soils. Stabilizers utilized have to satisfy noticeable performance, durability, low price, and can be easily implemented. Since cement kiln dust (CKD is industrial by-product, it would be a noble task if this waste material could be utilized for stabilization of sabkha soil. This study investigates the feasibility of utilizing CKD for improving the properties of sabkha soil. Soil samples are prepared with 2% cement and 10%, 20% or 30% CKD and are tested to determine their unconfined compressive strength (UCS, soaked California bearing ratio (CBR and durability. Mechanism of stabilization is studied utilizing advanced techniques, such as the scanning electron microscope (SEM, energy dispersive X-ray analysis (EDX, backscattered electron image (BEI and X-ray diffraction analysis (XRD. It is noted that the sabkha soil mixed with 2% cement and 30% CKD could be used as a sub-base material in rigid pavements. The incorporation of CKD leads to technical and economic benefits.

  16. Physicochemical characterization of cement kiln dust for potential reuse in acidic wastewater treatment

    International Nuclear Information System (INIS)

    Mackie, A.; Boilard, S.; Walsh, M.E.; Lake, C.B.

    2010-01-01

    Cement kiln dust (CKD) is a fine-grained material produced during the manufacture of cement. Current reuse options are limited and the bulk of CKD not reused in the cement manufacturing process is sent to landfills or stored on-site. Due to the calcium oxide (CaO) content of CKD, it has the potential to be used as a replacement for lime in treating acidic wastewaters such as acid rock drainage (ARD). This paper outlines the results of an examination of the physical and chemical properties of CKD samples collected from six cement plants. The CKD samples were analyzed for major oxides using X-ray diffraction (XRD), available lime, specific surface area, particle size, and morphology using scanning electron microscope (SEM) and compared with a commercial quicklime product. Conductivity, pH, and calcium concentrations of slaked CKD and quicklime solutions were used as indicators of reactivity of the CKD. Slaking of two of the CKD samples with the highest free lime contents (e.g., 34 and 37% free CaO) gave elevated pH values statistically comparable to those of the commercial quicklime sample that was characterized as having 87% available CaO. Acid neutralization trials indicate that even CKD samples with low free lime contents could be effective at neutralizing acidic wastewaters.

  17. Phytoextraction of chloride from a cement kiln dust (CKD) contaminated landfill with Phragmites australis.

    Science.gov (United States)

    McSorley, Kaitlin; Rutter, Allison; Cumming, Robert; Zeeb, Barbara A

    2016-05-01

    Cement kiln dust (CKD) is a globally produced by-product from cement manufacturing that is stockpiled or landfilled. Elevated concentrations of chloride pose toxic threats to plants and aquatic communities, as the anion is highly mobile in water and can leach into surrounding water sources. Re-vegetation and in situ phytoextraction of chloride from a CKD landfill in Bath, ON, Canada, was investigated with the resident invasive species Phragmites australis (haplotype M). Existing stands of P. australis were transplanted from the perimeter of the site into the highest areas of contamination (5.9×10(3)μg/g). Accumulation in the shoots of P. australis was quantified over one growing season by collecting samples from the site on a bi-weekly basis and analyzing for chloride. Concentrations decreased significantly from early May (24±2.2×10(3)μg/g) until mid-June (15±2.5×10(3)μg/g), and then remained stable from June to August. Shoot chloride accumulation was not significantly affected by water level fluctuations at the site, however elevated potassium concentrations in the soil may have contributed to uptake. Based on shoot chloride accumulation and total biomass, it was determined that phytoextraction from the CKD landfill can remove 65±4kg/km(2) of chloride per season. Based on this extraction rate, removal of chloride present in the highly contaminated top 10cm of soil can be achieved in 3-9years. This is the first study to apply phytotechnologies at a CKD landfill, and to successfully demonstrate in situ phytoextraction of chloride. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Physico-mechanical Properties of Electron Beam Irradiated Particle boards Based on Wood flour/ Polyethylene/Cement Kiln Dust Impregnated with Unsaturated Polyester

    International Nuclear Information System (INIS)

    Abdel-Rahman, H.A.; Khattab, M.M.; Ismail, M.R.

    2010-01-01

    Particle boards were fabricated by mixing wood flour (WF), low density polyethylene (LDPE) and cement kiln dust (CKD) under hot pressure; and then impregnated in unsaturated polyester resin. These impregnated particle boards were subjected to various doses of electron beam irradiation up to 50 kGy. The physico-mechanical properties were characterized in terms of flexural strength, impact strength, water absorption, thickness swelling, and the thermal stability. The results showed that the partial replacement of wood flour with cement kiln dust up to 20% by weight improved the values of flexural strength, and impact strength. However, the water absorption percentage and thickness swelling values decreased with increasing the CKD ratio up to 40%. Furthermore, the treatment with electron beam irradiation doses improved the physico-mechanical properties of the impregnated particle boards up to 50 kGy. The improved results were confirmed by scanning electron microscopy (SEM) and thermogravimetric analysis (TGA)

  19. Removal of Heavy Metal Ions by Using Composite of Cement Kiln Dust/Ethylene Glycol co Acrylic Acid Prepared by y-Irradiation

    International Nuclear Information System (INIS)

    Sokker, H.H.; Abdel-Rahman, H.A.; Khattab, M.M.; Ismail, M.R.

    2010-01-01

    Various composites of cement kiln dust (CKD) and poly(ethylene glycol co acrylic acid) using y-irradiation was investigated. The samples were prepared using three percentages of cement kiln dust namely, 20, 50 and 75 by wt % and mixed with an equimolar ratio (1:1) of ethylene glycol and acrylic acid then irradiated at doses; 10,20 and 30 kGy of gamma-irradiation. The results showed that (CKD) and poly(ethylene glycol co acrylic acid) composites were formed only at 30 kGy. In addition, CKD alone has the lowest degree of removal of heavy metal ions compared with the prepared composites. A composite containing 75% cement kiln dust by weight percentage, showed the highest degree of removal of cobalt ions, whereas, a composite of 20% CKD showed the highest degree for cadmium ion removal. While the composite of 75% CKD showed a higher selectivity of cobalt ion than cadmium ion in their mixed solution.

  20. Influence Of Cement Kiln Dust As Partial Replacement On Some Properties Of Ordinary And White Portland Cement

    Directory of Open Access Journals (Sweden)

    Salah Sharif

    2013-04-01

    Full Text Available Cement Kiln Dust (CKD is produced as a solid waste with large quantities during manufacturing of Portland cement clinker. The possibility of utilizing CKD as partial replacement for Ordinary Portland Cement (OPC and White Portland Cement (WPC produced in factories of the Iraqi cement state company has been examined in this study to fulfil the environmental and economical aims. Different percentages of CKD were blended with OPC and WPC mixes. The results show that the amount of water for normal consistency were increased with about 39 % and 31 % for OPC and WPC blended with 25 % CKD. The setting time (initial and final decreases with increasing percent of CKD added. Compressive strength decreases slightly with increasing CKD content up to 10 %. For 7- day curing time, it decreases 7 % and 9 % for OPC and WPC mixes, respectively. As percent of added CKD increases to more than 10 %, the compressive strength and other parameters where affected significantly. Overall results proved that OPC and WPC blended with up to 10 % CKD are admissible for passing relevant specification requirements.

  1. Bench-scale study of active mine water treatment using cement kiln dust (CKD) as a neutralization agent.

    Science.gov (United States)

    Mackie, Allison L; Walsh, Margaret E

    2012-02-01

    The overall objective of this study was to investigate the potential impact on settled water quality of using cement kiln dust (CKD), a waste by-product, to replace quicklime in the active treatment of acidic mine water. Bench-scale experiments were conducted to evaluate the treatment performance of calcium hydroxide (Ca(OH)(2)) slurries generated using four different CKD samples compared to a control treatment with quicklime (CaO) in terms of reducing acidity and metals concentrations in acid mine drainage (AMD) samples taken from the effluent of a lead/zinc mine in Atlantic Canada. Results of the study showed that all of the CKD samples evaluated were capable of achieving greater than 97% removal of total zinc and iron. The amount of solid alkaline material required to achieve pH targets required for neutralization of the AMD was found to be higher for treatment with the CKD slurries compared to the quicklime slurry control experiments, and varied linearly with the free lime content of the CKD. The results of this study also showed that a potential benefit of treating mine water with CKD could be reduced settled sludge volumes generated in the active treatment process, and further research into the characteristics of the sludge generated from the use of CKD-generated calcium hydroxide slurries is recommended. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Air pollution hazards in brick kilns

    Energy Technology Data Exchange (ETDEWEB)

    Aslam, M; Srivastava, R S; Minocha, A K; Gupta, R G [Central Building Research Institute, Roorkee (India)

    1994-02-01

    Three types of brick kiln - Bull's trench kiln of movable chimney type, Bull's trench kiln of fixed chimney type, and high draught kiln of normal capacity (25,000-30,000 bricks/day) fed manually with slack coal and other local fuels - were investigated for stack emissions. Dust and hydrocarbons were identified as chief pollutants. Particle size analysis of dust emitted from movable chimney kiln and its impact on ambient air quality were also studied. Based on these studies, recommendations have been drawn on their comparative pollution hazard and need for optimization of operational parameters to improve their thermal performance and reduce pollution emission. 15 refs., 4 tabs.

  3. Mechanism for the stabilization/solidification of arsenic-contaminated soils with Portland cement and cement kiln dust.

    Science.gov (United States)

    Yoon, In-Ho; Moon, Deok Hyun; Kim, Kyoung-Woong; Lee, Keun-Young; Lee, Ji-Hoon; Kim, Min Gyu

    2010-11-01

    In this study, the mechanism for the stabilization/solidification (S/S) of arsenic (As)-contaminated soils with Portland cement (PC), and cement kiln dust (CKD) using 1 N HCl extraction fluid, X-ray powder diffraction (XRPD), X-ray absorption near edge structure (XANES) and Extended X-ray absorption fine structure (EXAFS) spectroscopy was investigated. The degree of As immobilization after stabilization was assessed using a 1 N HCl extraction on the basis of the Korean Standard Test (KST). After 1 day of curing with 30 wt% PC and 7 days of curing with 50 wt% CKD, the concentration of As leached from the amended soils was less than the Korean countermeasure standard (3 mg L(-1)). The As concentrations in the leachate treated with PC and CKD were significantly decreased at pH > 3, indicating that pH had a prevailing influence on As mobility. XRPD results indicated that calcium arsenite (Ca-As-O) and sodium calcium arsenate hydrate (NaCaAsO(4).7.5H(2)O) were present in the PC- and CKD-treated slurries as the key phases responsible for As(III) and As(V) immobilization, respectively. The XANES spectroscopy confirmed that the As(III) and As(V) oxidation states of the PC and CKD slurry samples were consistent with the speciated forms in the crystals identified by XRPD. EXAFS spectroscopy showed As-Ca bonding in the As(III)-PC and As(III)-CKD slurries. The main mechanism for the immobilization of As-contaminated soils with PC and CKD was strongly associated with the bonding between As(III) or As(V) and Ca. Copyright 2010 Elsevier Ltd. All rights reserved.

  4. Assessment of cement kiln dust (CKD) for stabilization/solidification (S/S) of arsenic contaminated soils.

    Science.gov (United States)

    Moon, Deok Hyun; Wazne, Mahmoud; Yoon, In-Ho; Grubb, Dennis G

    2008-11-30

    A stabilization/solidification (S/S) process for arsenic (As) contaminated soils was evaluated using cement kiln dust (CKD). Laboratory-prepared slurries, made of either kaolinite or montmorillonite, and field soils spiked with either As(3+) or As(5+) were prepared and treated with CKD ranging from 10 to 25 wt%. Sodium arsenite and sodium arsenate at 0.1 wt% were used to simulate arsenite (As(3+)) and arsenate (As(5+)) source contamination in soils, respectively. The effectiveness of treatment was evaluated at curing periods of 1- and 7-days based on the toxicity characteristic leaching procedure (TCLP). As-CKD and As-clay-CKD slurries were also spiked at 10 wt% to evaluate As immobilization mechanism using X-ray powder diffraction (XRPD) analyses. Overall, the TCLP results showed that only the As(5+) concentrations in kaolinite amended with 25 wt% CKD after 1 day of curing were less than the TCLP regulatory limit of 5mg/L. Moreover, at 7 days of curing, all As(3+) and As(5+) concentrations obtained from kaolinite soils were less than the TCLP criteria. However, none of the CKD-amended montmorillonite samples satisfied the TCLP-As criteria at 7 days. Only field soil samples amended with 20 wt% CKD complied with the TCLP criteria within 1 day of curing, where the source contamination was As(5+). XRPD and scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) results showed that Ca-As-O and NaCaAsO(4).7.5H(2)O were the primary phases responsible for As(3+) and As(5+) immobilization in the soils, respectively.

  5. Assessment of cement kiln dust (CKD) for stabilization/solidification (S/S) of arsenic contaminated soils

    International Nuclear Information System (INIS)

    Moon, Deok Hyun; Wazne, Mahmoud; Yoon, In-Ho; Grubb, Dennis G.

    2008-01-01

    A stabilization/solidification (S/S) process for arsenic (As) contaminated soils was evaluated using cement kiln dust (CKD). Laboratory-prepared slurries, made of either kaolinite or montmorillonite, and field soils spiked with either As 3+ or As 5+ were prepared and treated with CKD ranging from 10 to 25 wt%. Sodium arsenite and sodium arsenate at 0.1 wt% were used to simulate arsenite (As 3+ ) and arsenate (As 5+ ) source contamination in soils, respectively. The effectiveness of treatment was evaluated at curing periods of 1- and 7-days based on the toxicity characteristic leaching procedure (TCLP). As-CKD and As-clay-CKD slurries were also spiked at 10 wt% to evaluate As immobilization mechanism using X-ray powder diffraction (XRPD) analyses. Overall, the TCLP results showed that only the As 5+ concentrations in kaolinite amended with 25 wt% CKD after 1 day of curing were less than the TCLP regulatory limit of 5 mg/L. Moreover, at 7 days of curing, all As 3+ and As 5+ concentrations obtained from kaolinite soils were less than the TCLP criteria. However, none of the CKD-amended montmorillonite samples satisfied the TCLP-As criteria at 7 days. Only field soil samples amended with 20 wt% CKD complied with the TCLP criteria within 1 day of curing, where the source contamination was As 5+ . XRPD and scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX) results showed that Ca-As-O and NaCaAsO 4 .7.5H 2 O were the primary phases responsible for As 3+ and As 5+ immobilization in the soils, respectively

  6. Investigation into the use of cement kiln dust in high density sludge (HDS) treatment of acid mine water.

    Science.gov (United States)

    Mackie, Allison L; Walsh, Margaret E

    2015-11-15

    The purpose of this study was to investigate the potential to replace lime with cement kiln dust (CKD) in high density sludge (HDS) treatment of acid mine drainage (AMD). The bench-scale study used two water samples: AMD sampled from a lead-zinc mine with high concentrations of iron (Fe), zinc (Zn), and arsenic (As) (Fe/Zn-AMD) and a synthetic AMD solution (Syn-AMD) spiked with ferric sulfate (Fe2(SO4)3). Arsenic was found to be significantly reduced with CKD-HDS treatment of Fe/Zn-AMD compared to lime-HDS treatment, to concentrations below the stringent mine effluent discharge regulation of 0.10 mg As/L (i.e., 0.04 ± 0.02 mg/L). Both CKD- and lime-HDS treatment of the two AMD samples resulted in settled water Fe concentrations above the stringent discharge guideline of 0.3 mg Fe/L. CKD addition in the HDS process also resulted in high settled water turbidity, above typical discharge guidelines of 15 mg TSS/L. CKD-HDS treatment was found to result in significantly improved settled solids (i.e., sludge) quality compared to that generated in the lime-HDS process. HDS treatment with CKD resulted in 25-88% lower sludge volume indices, 2 to 9 times higher % wet solids, and 10 to 20 times higher % dry solids compared to lime addition. XRD and XPS testing indicated that CKD-HDS sludge consisted of mainly CaCO3 and SiO2 with Fe(3+) precipitates attached at particle surfaces. XRD and XPS testing of the lime-HDS generated sludge showed that it consisted of non-crystalline Fe oxides typical of sludge formed from precipitates with a high water concentration. Increased sedimentation rates were also found for CKD (1.3 cm/s) compared to lime (0.3 cm/s). The increased solids loading with CKD addition compared to lime addition in the HDS process was suggested to both promote surface complexation of metal precipitates with insoluble CKD particles and increase compression effects during Type IV sedimentation. These mechanisms collectively contributed to the reduced water content of

  7. Use of Cement Kiln Dust, Blast Furnace Slag and Marble Sludge in the Manufacture of Sustainable Artificial Aggregates by Means of Cold Bonding Pelletization.

    Science.gov (United States)

    Colangelo, Francesco; Cioffi, Raffaele

    2013-07-25

    In this work, three different samples of solid industrial wastes cement kiln dust (CKD), granulated blast furnace slag and marble sludge were employed in a cold bonding pelletization process for the sustainable production of artificial aggregates. The activating action of CKD components on the hydraulic behavior of the slag was explored by evaluating the neo-formed phases present in several hydrated pastes. Particularly, the influence of free CaO and sulfates amount in the two CKD samples on slag reactivity was evaluated. Cold bonded artificial aggregates were characterized by determining physical and mechanical properties of two selected size fractions of the granules for each studied mixture. Eighteen types of granules were employed in C28/35 concrete manufacture where coarser natural aggregate were substituted with the artificial ones. Finally, lightweight concretes were obtained, proving the suitability of the cold bonding pelletization process in artificial aggregate sustainable production.

  8. Use of Cement Kiln Dust, Blast Furnace Slag and Marble Sludge in the Manufacture of Sustainable Artificial Aggregates by Means of Cold Bonding Pelletization

    Directory of Open Access Journals (Sweden)

    Raffaele Cioffi

    2013-07-01

    Full Text Available In this work, three different samples of solid industrial wastes cement kiln dust (CKD, granulated blast furnace slag and marble sludge were employed in a cold bonding pelletization process for the sustainable production of artificial aggregates. The activating action of CKD components on the hydraulic behavior of the slag was explored by evaluating the neo-formed phases present in several hydrated pastes. Particularly, the influence of free CaO and sulfates amount in the two CKD samples on slag reactivity was evaluated. Cold bonded artificial aggregates were characterized by determining physical and mechanical properties of two selected size fractions of the granules for each studied mixture. Eighteen types of granules were employed in C28/35 concrete manufacture where coarser natural aggregate were substituted with the artificial ones. Finally, lightweight concretes were obtained, proving the suitability of the cold bonding pelletization process in artificial aggregate sustainable production.

  9. Dust extraction from gas in cement kilns, using bag filters; Depoussierage des gaz de four cimentier par les filtres a manches

    Energy Technology Data Exchange (ETDEWEB)

    Harmegnies, M. [CALCIA, 78 - Guerville (France). Direction Technique

    1996-12-31

    After a review of regulations concerning cement plant emissions, the two main cement production techniques (dry and semi-dry processes) are described and the electrostatic and bag filter de-dusting techniques are compared. Examples of pilot applications of these techniques in two French cement plants are presented and operating results (performances, transient procedures, costs) are discussed

  10. Energy saving plan for lime calcining kiln

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Lime calcining kilns operating in China are of old type, consuming more heat energy by 30% or more than the latest type kilns. For the purpose of the COP3 joint implementation, a renewal plan was discussed taking up Benxi Steel Group Company as the object. The new type kiln is a parallel flow energy regenerating (Maerz) kiln. It has as high thermal efficiency as 900 kcal/kg of product. Annual fuel conservation as converted into crude oil will be 7.49x10{sup 3} tons, annual fuel cost reduction will be 101,200,000 yuan, and annual reduction in CO2 emission will be 23,200 tons. The estimated cost required for the project will be 991 million yen, or 66,070,000 yuan if the exchange rate is assumed to be 15 yen to one yuan. The profitability was discussed based on using bank loans and the special environmental yen loan. The investment recovering period was calculated as 7.9 years. This provides no realizability as a project on the business base. However, China strongly desires renewal of the facilities because of discharge of dust from old type facilities, and inferior quality of lime products. The project could be a candidate without doubt if the CDM system will have been established. (NEDO)

  11. Rotary kiln arrangements

    International Nuclear Information System (INIS)

    Hayes, M.R.

    1983-01-01

    In a rotary kiln arrangement in which a reaction is to occur between counterflowing reactants and material is discharged through a hopper, an injector for at least one reactant extends into a reaction zone of the kiln, means being provided for the reaction zone to be maintained within a desired temperature range. The said means includes heating elements for adjusting the temperature of the injected reactant to a temperature within the desired range while it is in the injector. The arrangement may be used in the production of uranium oxides from uranium hexafluoride. (author)

  12. Refuse derived fuels in Cement Kilns: Italian experience

    International Nuclear Information System (INIS)

    Del Borghi, M.; Strazza, C.; Del Borghi, A.

    2009-01-01

    This study investigates the results of a year (2006) of air emissions gathering in the various Italian cement plants, and, in particular, on 73 kilns subdivided by production class, kiln type and alternative fuels use for type and quantity. The emission parameters considered have been: total dust, SO 2 , NOx, CO, TOC, HCl, HF, metals, PAH and PCDD/F. The work has involved a comparison between the results of the average concentrations detected for the various pollutants, separately for the plants using only traditional fuels and using also alternative fuels. The obtained results show that the use of alternative fuels by the 22 kilns investigated has not any influence on the emission values of the pollutants examined; on the contrary, in certain cases these emissions result less than the limits legally allowed for the use of traditional fuels. A comparison between the results obtained from the Italian kilns and those published by Cembureau from 200 European kilns, confirms that the emission performances of cement kilns appear independent for the use of alternative fuels with the percentages usually employed. This study also highlights the benefits on the global environmental balance for the use of RDF as alternative fuel. [it

  13. Case study: improvement of performance of cement industry rotary kilns by using a solid radiotracers

    International Nuclear Information System (INIS)

    Sebastian, C.; Maghella, G.; Mamani, E.

    2000-12-01

    In the present report, residence time distribution (RTD) of the cement blended raw meal has been determined by the use of 7,4x10 8 Bq (20 mCi) of La 40 as a dust radioactive tracer in the chemical form of La 2 O 3 . Five scintillation detector were installed alongside the kiln. Analysis and interpretation of response curves were made to draw conclusions about the improvement of the rotary kiln performance

  14. Kiln emissions and potters' exposures.

    Science.gov (United States)

    Hirtle, B; Teschke, K; van Netten, C; Brauer, M

    1998-10-01

    Some ten thousand British Columbia potters work in small private studios, cooperative facilities, educational institutions, or recreation centers. There has been considerable concern that this diffuse, largely unregulated activity may involve exposures to unacceptable levels of kiln emissions. Pottery kiln emissions were measured at 50 sites--10 from each of 5 categories: professional studios, recreation centers, elementary schools, secondary schools, and colleges. Area monitoring was done 76 cm from firing kilns and 1.6 m above the floor to assess breathing zone concentrations of nitrogen dioxide, carbon monoxide, sulfur dioxide, fluorides, aldehydes, aluminum, antimony, arsenic, barium, beryllium, boron, cadmium, chromium, cobalt, copper, gold, iron, lead, lithium, magnesium, manganese, mercury, nickel, selenium, silver, vanadium, and zinc. Personal exposures to the same metals were measured at 24 sites. Almost all measured values were well below permissible concentrations for British Columbia work sites and American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit values (TLVs) with the following two exceptions. A single firing duration (495 minute) acrolein measurement adjacent to an electric kiln (0.109 ppm) exceeded these guidelines. One 15-minute sulfur dioxide measurement collected adjacent to a gas kiln (5.7 ppm) exceeded the ACGIH short-term exposure limit. The fact that concentrations in small, ventilated kiln rooms ranked among the highest measured gives rise to concern that unacceptable levels of contamination may exist where small kiln rooms remain unventilated. Custom designed exhaust hoods and industrial heating, ventilating, and air-conditioning systems were the most effective ventilation strategies. Passive diffusion and wall/window fans were least effective.

  15. 40 CFR 63.1343 - Standards for kilns and in-line kiln/raw mills.

    Science.gov (United States)

    2010-07-01

    .../raw mills. 63.1343 Section 63.1343 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Industry Emission Standards and Operating Limits § 63.1343 Standards for kilns and in-line kiln/raw mills. (a) General. The provisions in this section apply to each kiln, each in-line kiln/raw mill, and any...

  16. Occupational Health Hazards of Women Working in Brick Kiln and Construction Industry

    Directory of Open Access Journals (Sweden)

    V. G Vaidya

    2015-01-01

    Full Text Available Background: In brick kiln and construction industry the exposure to carbon monoxide and silica dust is the most common occupational hazard to the workers in these industries. A study on occupational health hazards of working women in these two unorganized sectors was undertaken by Lokmanya Medical Research Centre. Objectives: To study the effect of work site environment on the health of the women working in brick kiln and construction industry. An attempt was also made to study the seasonal changes in the concentration of carbon monoxide and dust at the worksite. Material and Methods: A cross-sectional study was conducted among the working women (age 18-40 years at brick kilns and construction sites during summer and winter season. They were examined primarily to assess the effect of working environment on health. Gasteck Detector Pump of model 800 and air sampling instrument (SKC Air Check–52 were used to measure concentration of carbon monoxide and dust in the air respectively. Results: There were 66% of women who were in the age group of 18-40 years and most of them (94% were married. At brick kiln sites, average CO exposure was 62.8 ppm and 55.5 ppm and average dust exposure was 3 3 146.1 mg/m and 91.4 mg/m in summer and winter season respectively.At construction sites, average dust exposure was 41.5 ppm and 90.8 ppm in summer and winter. Conclusion: Both exposure to CO and dust were more in summer than in winter in brick kiln industry whereas in construction industry the exposure to dust was more in winter season. A high level of morbidity in the form of headache, bodyache, problems with vision, cough and breathlessness were observed in both industries. It is strongly recommended to take pollution control measures.

  17. A Pottery Electric Kiln Using Decompression

    Science.gov (United States)

    Naoe, Nobuyuki; Yamada, Hirofumi; Nakayama, Tetsuo; Nakayama, Minoru; Minamide, Akiyuki; Takemata, Kazuya

    This paper presents a novel type electric kiln which fires the pottery using the decompression. The electric kiln is suitable for the environment and the energy saving as the pottery furnace. This paper described the baking principle and the baking characteristic of the novel type electric kiln.

  18. Characteristics of dioxin emissions from a Waelz plant with acid and basic kiln mode.

    Science.gov (United States)

    Hung, Pao Chen; Chi, Kai Hsien; Chen, Mei Lien; Chang, Moo Been

    2012-01-30

    The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were measured in the flue gas of a Waelz plant operated in acid and basic modes, respectively. To abate (PCDD/F) and other pollutants, the plant operates with a post-treatment of flue gases by activated carbon injection and subsequent filtration. Relatively high PCDD/F discharge by fly ashes is found with acid kiln mode of the Waelz process. Therefore, basic kiln mode of the Waelz process is investigated and compared in this plant. With the adsorbent injection rate of 7 kg/h (95 mg/Nm(3)), the PCDD/F concentration in stack gas was measured as 0.123 ng I-TEQ/Nm(3) in the basic operating mode. The added Ca(OH)(2) reacted with metal catalysts and HCl((g)) in the flue gas and thus effectively suppressed the formation of PCDD/Fs. PCDD/F concentrations in fly ashes sampled from the dust settling chamber, cyclone, primary filter and secondary filter in basic kiln mode were significantly lower than that in acid kiln mode. Total PCDD/F emission on the basis of treating one kg of electric arc furnace dust in the basic operation mode was 269 ng I-TEQ/kg EAF-dust treated which was significantly lower than that in acid mode (640 ng I-TEQ/kg EAF-dust treated). Copyright © 2011 Elsevier B.V. All rights reserved.

  19. 40 CFR 270.235 - Options for incinerators, cement kilns, lightweight aggregate kilns, solid fuel boilers, liquid...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Options for incinerators, cement kilns... Technology (MACT) Standards § 270.235 Options for incinerators, cement kilns, lightweight aggregate kilns... incinerator, cement kiln, lightweight aggregate kiln, solid fuel boiler, liquid fuel boiler, or hydrochloric...

  20. Timber drying kilns using solar energy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-15

    The objective of this project was to research the potential for solar kilns for drying timber in tropical countries (Guyana, Honduras and Belize) and produce a manual which will provide the knowledge necessary to build and operate a solar kiln. The main output of the project is the manual Solar Heated Timber Drying Kilns - a Manual on their Design and Operation. The manual covers:- background information; selection of construction materials; methods of kiln construction; kiln operation and maintenance procedure. The manual has been designed to provide the necessary knowledge and confidence to build and operate a solar kiln, and ultimately benefit from an improved product. Specifically, the manual will benefit small building construction units, furniture and joinery manufacturers and sawmill operators in developing and developed countries worldwide. (author)

  1. Turbulent diffusion in the flame of a rotary kiln

    Energy Technology Data Exchange (ETDEWEB)

    Strekotin, V.V.; Telegin, A.A.; Lisin, F.N.; Malysheva, O.I.

    1987-09-01

    Experimental data on the distribution of velocities in the stream in the flow of air from models of a burner with a normal annular Laval nozzle and a burner with an increase in the angle of opening of the stream under supersonic conditions were obtained. The results of the work may be used in the design of burners for rotary kilns. According to the experimental data the coefficient of turbulent diffusion reaches a value of 0.0071 m/sup 2//sec for a pure flow and is reduced by 30% with an increase in the dust content from 0 to 1 kg/kg. It is desirable to use the data obtained in calculations of the flame processes and selection of means of intensification of the process of mixing of the fuel with the oxidizer in the presence of dust.

  2. EDXRF analysis of Yanhedian Ru kiln and Jun official kiln porcelain

    International Nuclear Information System (INIS)

    Wen Chang; Zhao Huixian; Li Guoxia; Gao Zhengyao; Zhao Weijuan; Sun Hongwei; Guo Min; Xie Jianzhong; Li Rongwu; Guo Peiyu

    2009-01-01

    The chemical components of the body and glaze samples of some Ru porcelains from Yanhedian kiln and Jun official porcelains from Juntai kiln are determined by the technology of Energy Dispersive X-ray Fluorescence(EDXRF) in this work. The difference of the two kiln's glaze and body are analyzed by factor analysis method of Multi-dimensional statistical analysis. The results indicate that Yanhedian Ru porcelains can be well distinguished from Jun official porcelains from Juntai kiln. This evidence once again proves that Jun ceramics and Ru ceramics can be distinguished obviously. (authors)

  3. Emission during the firing of chrome-magnesite products in tunnel kilns

    Energy Technology Data Exchange (ETDEWEB)

    Krechin, Yu.V.; Telegin, S.V.; Ivanov, N.M.; Kasimov, A.M.; Plichko, E.P.; Sverkov, Yu.M.; Maksimov, B.N.

    1986-11-01

    When chrome-magnesite products are fired in tunnel furnaces, the concentration in the effluent gas of dust is 110-150; of Cr/sub 7/O/sub 3/, 5-7; NO/sub x/, 20-35; CO, 100-125; SO/sub 2/, 25-40; and SO/sub 3/, 30-70 mg/m/sup 3/. The emission dust is finely dispersed. The average size of the particles of dust is 0.3, the minimum 0.05, and the maximum 1 ..mu..m. There is no hydrogen sulfide, NO/sub 2/, or CrO/sub 3/ in the emission. Dust and nitrogen oxides are formed in the firing zone of the kiln. The formation of dust and NO/sub 2/ depends on the air-consumption coefficient. The use of the pipe-in-pipe type of ports does not provide good gas combustion. To improve the operation of the kiln and the combustion of the natural gas it is recommended that instead of the obsolescent tube-in-tube ports, the ports developed by the Eastern Institute of Refractories be installed since they have given good results in tests. To improve the scattering effect of the removal of dust in the existing equipment it is recommended that the height of the flue stacks be increased to 40-50 m.

  4. Fabrication works on rotary kiln fluidized bed

    International Nuclear Information System (INIS)

    Shahazrin Mohd Nasir; Mohamad Azman Che Mat Isa; Mohamad Puad Haji Abu; Mohd Fairus Abdul Farid

    2005-01-01

    Rotary kiln has been widely used in incineration and studied by many researches. Solid wastes of various shapes, sizes and heat value can be fed into rotary kiln either in batches or continually. Waste combustion in rotary kiln involves rotation method and the residence time depends on the length and diameter of the rotary kiln and the total stichomythic air given to the system.Rocking system is another technology used in incinerator. In the rocking system, internal elements in the combustion chamber move to transports and mix the burning waste so that all combustible material in the waste is fully burnt. Another technology in incinerator is the fluidized bed. This method uses air to fluidized the sand thus enhancing the combustion process. The total air is controlled in order to obtain a suitable fluidized condition.This preliminary study was conducted to study the feasibility of an incinerator system when three components viz. the rotary kiln, rocking system and fluidized bed are combined. This research was also conducted to obtain preliminary data parameters of the three components such as the suitable temperature, the angle of the kiln, residence time, total air for fluidization, rocking speed and the devolatilization rate. The samples used in this research were the palm oil kernel shells. (Author)

  5. Dissolution of heavy metals from electrostatic precipitator (ESP) dust ...

    African Journals Online (AJOL)

    Coal based sponge iron industries in India generate considerable quantity of solid waste, 40% of which is flue dust produced from the electrostatic precipitator (ESP) connected to rotary kiln. This paper reports the dissolution of Zn, Cu, Pb, Mn and Fe from the ESP dust using three fungal species, Aspergillus niger, ...

  6. 27 CFR 9.27 - Lime Kiln Valley.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Lime Kiln Valley. 9.27... OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.27 Lime Kiln Valley. (a) Name. The name of the viticultural area described in this section is “Lime Kiln Valley...

  7. Design Robust Controller for Rotary Kiln

    Directory of Open Access Journals (Sweden)

    Omar D. Hernández-Arboleda

    2013-11-01

    Full Text Available This paper presents the design of a robust controller for a rotary kiln. The designed controller is a combination of a fractional PID and linear quadratic regulator (LQR, these are not used to control the kiln until now, in addition robustness criteria are evaluated (gain margin, phase margin, strength gain, rejecting high frequency noise and sensitivity applied to the entire model (controller-plant, obtaining good results with a frequency range of 0.020 to 90 rad/s, which contributes to the robustness of the system.

  8. 40 CFR 63.1344 - Operating limits for kilns and in-line kiln/raw mills.

    Science.gov (United States)

    2010-07-01

    ... kiln/raw mills. 63.1344 Section 63.1344 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... mills. (a) The owner or operator of a kiln subject to a D/F emission limitation under § 63.1343 must... specified in paragraph (b) of this section. The owner or operator of an in-line kiln/raw mill subject to a D...

  9. Case study: improvement of performance of cement industry rotary kilns by using a solid radiotracers; Caso estudio: Mejora de la eficiencia en hornos rotativos de la industria del cemento utilizando radioisotopos

    Energy Technology Data Exchange (ETDEWEB)

    Sebastian, C; Maghella, G; Mamani, E [Direccion de Aplicaciones. Instituto Peruano de Energia Nuclear, Lima (Peru)

    2000-12-01

    In the present report, residence time distribution (RTD) of the cement blended raw meal has been determined by the use of 7,4x10{sup 8} Bq (20 mCi) of La 40 as a dust radioactive tracer in the chemical form of La{sub 2}O{sub 3}. Five scintillation detector were installed alongside the kiln. Analysis and interpretation of response curves were made to draw conclusions about the improvement of the rotary kiln performance.

  10. Lime Kiln Dust for Treated Subgrades : Final Report

    Science.gov (United States)

    2017-11-01

    Chemical and cementitious materials are often used to modify and stabilize the subgrade soils that serve as foundations for pavements. Improvement of the subgrade provides a better working platform for construction of the layers above and improves th...

  11. Lime Kiln Dust for Treated Subgrades : Technical Summary

    Science.gov (United States)

    2017-11-01

    Chemical and cementitious materials are often used to modify and stabilize the subgrade soils that serve as foundations for pavements. Improvement of the subgrade provides a better working platform for construction of the layers above and improves th...

  12. Coal acid mine drainage treatment using cement kiln dust

    Directory of Open Access Journals (Sweden)

    Edgar Alberto Martínez

    2014-01-01

    Full Text Available Los sulfuros están presentes en distintas rocas. Durante las actividades mineras y el proceso de remoción de sulfuros se pueden producir Drenajes Ácidos de Minería (DAM, con iones de sulfato (SO4-2. Los DAMs son fuente de polución en las actividades mineras y en Colombia su descarga en los cuerpos de agua debe cumplir las regulaciones nacionales (pH entre 5 y 9. Polvo de horno cementero (CKD, con carbonato de calcio principalmente, de una planta de Cementos Argos S.A. fue usado para neutralizar un DAM generado en la biodesulfurización de carbón. Los DAMs neutralizados tuvieron pHs entre 7,72 y 8,05 y la eliminación de sulfatos entre 67% a 70%. El precipitado se secó y analizó para determinar su composición química y mineralógica. Se encontró humedad entre 69% y 81%; yeso con un 50% de pureza aproximadamente y carbonato de calcio. Esta composición lo hace adecuado para uso en la producción de cemento.

  13. Environmental impact of incineration of calorific industrial waste: rotary kiln vs. cement kiln.

    Science.gov (United States)

    Vermeulen, Isabel; Van Caneghem, Jo; Block, Chantal; Dewulf, Wim; Vandecasteele, Carlo

    2012-10-01

    Rotary kiln incinerators and cement kilns are two energy intensive processes, requiring high temperatures that can be obtained by the combustion of fossil fuel. In both processes, fossil fuel is often substituted by high or medium calorific waste to avoid resource depletion and to save costs. Two types of industrial calorific waste streams are considered: automotive shredder residue (ASR) and meat and bone meal (MBM). These waste streams are of current high interest: ASR must be diverted from landfill, while MBM can no longer be used for cattle feeding. The environmental impact of the incineration of these waste streams is assessed and compared for both a rotary kiln and a cement kiln. For this purpose, data from an extensive emission inventory is applied for assessing the environmental impact using two different modeling approaches: one focusing on the impact of the relevant flows to and from the process and its subsystems, the other describing the change of environmental impact in response to these physical flows. Both ways of assessing emphasize different aspects of the considered processes. Attention is paid to assumptions in the methodology that can influence the outcome and conclusions of the assessment. It is concluded that for the incineration of calorific wastes, rotary kilns are generally preferred. Nevertheless, cement kilns show opportunities in improving their environmental impact when substituting their currently used fuels by more clean calorific waste streams, if this improvement is not at the expense of the actual environmental impact. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Numerical Modeling of Rotary Kiln Productivity Increase

    NARCIS (Netherlands)

    Romero-Valle, M.A.; Pisaroni, M.; Van Puyvelde, D.; Lahaye, D.J.P.; Sadi, R.

    2013-01-01

    Rotary kilns are used in many industrial processes ranging from cement manufacturing to waste incineration. The operating conditions vary widely depending on the process. While there are many models available within the literature and industry, the wide range of operating conditions justifies

  15. Wood fuel use in Tanzania rural-based industries. Brick kiln studies in Tanzania

    Energy Technology Data Exchange (ETDEWEB)

    Kiwele, P.M.; Mbise, H.A.; Mwihava, N.C.X.; Svenningsson, P.J.

    1999-07-01

    years ago indicate that SEC figures for Zimbabwe vary from 1.93 to 2.71 MJ/kg. Data from other sources indicate figures in the range of 3.8 to 7.5 MJ/kg. With regard to the trial runs made using saw dust and coal, the SEC figures were in the range of 1.4 to 2.5 MJ/kg, which are comparable to those found when wood fuel alone is utilised. Generally, a high SEC could be a reflection of well-burnt bricks, while low SEC could imply poorly burnt bricks. It may therefore be difficult to compare SEC for different kilns unless the quality of the product is pre-determined. It should be noted that the observed results do not necessarily undermine the potential for future utilisation of alternative fuels like sawdust and coal dust. In this study the main areas of energy losses were found to be related to: inappropriate kiln configuration and volume; quality of fuel used; inadequate management of the firing process; poor control of the leakage points; over-firing and inappropriate size of bricks. The main recommendations in this study include: the need to conduct an environmental impact assessment of the brick-making activity; the need to establish local standards to ensure reliability; the need to use alternative fuels such as Euphorbia tiruculi and Eucalyptus since they grow faster and therefore reducing pressure on the natural forests; and preparation of operating manuals in both Swahili and English languages.

  16. Surplus biomass through energy efficient kilns

    International Nuclear Information System (INIS)

    Anderson, Jan-Olof; Westerlund, Lars

    2011-01-01

    Highlights: → The magnitude of the national heat demand for drying lumber in kilns is established. → Each part of the total heat consumption is divided and shown between the main drying conditions. → The potential to increase the energy efficiency in kilns with available techniques is presented. → The market demand for the biomass, available with increase kiln energy efficiency, is reviled. -- Abstract: The use of biomass in the European Union has increased since the middle of the 1990s, mostly because of high subsidies and CO 2 emission regulation through the Kyoto protocol. The sawmills are huge biomass suppliers to the market; out of the Swedish annual lumber production of 16.4 Mm 3 , 95% is produced by medium to large-volume sawmills with a lumber quotient of 47%. The remaining part is produced as biomass. An essential part (12%) of the entering timber is used for supply of heat in their production processes, mostly in the substantial drying process. The drying process is the most time and heat consuming process in the sawmill. This study was undertaken to determine the sawmills' national use of energy and potential magnitude of improvements. If the drying process can be made more effective, sawmills' own use of biomass can be decreased and allow a considerably larger supply to the biomass market through processed or unprocessed biomass, heat or electricity production. The national electricity and heat usage when drying the lumber have been analysed by theoretical evaluation and experimental validation at a batch kiln. The main conclusion is that the heat consumption for drying lumber among the Swedish sawmills is 4.9 TW h/year, and with available state-of-the-art techniques it is possible to decrease the national heat consumption by approximately 2.9 TW h. This additional amount of energy corresponds to the market's desire for larger energy supply.

  17. Digital Kilns and Furnaces——the Development Direction of Industrial Kilns and Furnaces in the 21st Century

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaoming; HUANG Zhichu; ZHANG Jiafan

    2006-01-01

    The digital manufacturing theory is applied to the special manufacturing equipments--industrial kilns and furnaces; the concept of digital kilns & furnaces is put forward. The present status of research and application for digital technologies in fuel industrial kilns & furnaces is also introduced. Then, take the case of gas fuel kilns & furnaces, their main key technical issues are discussed. Digital kilns & furnaces as an important constituent of the digital equipments are the crucial base of the digital manufacturing. The value of research on digital kilns & furnaces and the application prospect are undoubted. It will improve product quality, reduce the manpower cost, enhance product market competitive ability, promote comprehensively tradition industries such as ceramics, metallurgy industry,and so on.

  18. Thermal behavior of kiln cars while traveling through a tunnel kiln

    Directory of Open Access Journals (Sweden)

    Yu Zhang

    2015-05-01

    Full Text Available The kiln car is widely used as a kind of transport equipment in the current ceramic industry, and it is heated to the firing temperature and cooled down to the ambient temperature with products in the tunnel kiln. And the burning of the ceramics requires a lot of energy, and the efficiency is relatively low within 30% or even less. In addition, the mass ratio between car and ware can be more than 50%. So the energy loss of car also occupies a great part in total energy consumption. In this work, a mathematical model will be created to describe the temperature distribution inside the kiln car while it travels through the tunnel kiln. All the used parameters are from real ceramic industry. The operative process is assumed as a countercurrent heat exchanger. Both the convection and radiation are considered as boundary condition in the model. Furthermore, the thermal results of car and the specific energy consumption of car in the standard case will be demonstrated. Finally, the influences of different thermal physical parameters on the energy consumption of car will be investigated, and the possible optimization measures of car are proposed through comparing the different specific energy losses.

  19. Investment opportunity : the FPL low-cost solar dry kiln

    Science.gov (United States)

    George B. Harpole

    1988-01-01

    Two equations are presented that may be used to estimate a maximum investment limit and working capital requirements for the FPL low-cost solar dry kiln systems. The equations require data for drying cycle time, green lumber cost, and kiln-dried lumber costs. Results are intended to provide a preliminary estimate.

  20. 52 KILN EFFICIENCY AND INSULATION. Anthony Obiy Etuokwu ...

    African Journals Online (AJOL)

    HP-G61

    52. KILN EFFICIENCY AND INSULATION. Anthony Obiy Etuokwu. Department of Fine and Industrial Arts,. Niger Delta University,. Wilberforce Island, Bayelsa State. etuokwutony@yahoo.com. Introduction. The kiln is an insulating fire chamber that has the ability to retain the heat that is generated into it, and utilizes such heat ...

  1. Community Geothermal Technology Program: Experimental lumber drying kiln. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Leaman, D.; Irwin, B.

    1989-10-01

    Goals were to demonstrate feasibility of using the geothermal waste effluent from the HGP-A well as a heat source for a kiln operation to dry hardwoods, develop drying schedules, and develop automatic systems to monitor/control the geothermally heated lumber dry kiln systems. The feasibility was demonstrated. Lumber was dried in periods of 2 to 6 weeks in the kiln, compared to 18 months air drying and 6--8 weeks using a dehumidified chamber. Larger, plate-type heat exchangers between the primary fluid and water circulation systems may enable the kiln to reach the planned temperatures (180--185 F). However, the King Koa partnership cannot any longer pursue the concept of geothermal lumber kilns.

  2. NAA study on characteristics and sources of raw materials of celadon bodies from Qingliangsi kiln and Zhanggongxiang kiln

    International Nuclear Information System (INIS)

    Wu Zhanjun; Zhao Weijuan; Lu Xiaoke; Li Guoxia; Guo Min; Xie Jianzhong; Qiu Xia; Feng Songlin

    2007-01-01

    Thirty-seven samples of ancient Chinese Ru porcelain bodies unearthed from Qingliangsi kiln (containing 32 Ru official porcelain bodies and 5 Ru folk porcelain bodies), thirty-two samples of ancient celadon bodies from Zhanggongxiang kiln, and fourteen samples of modern mineral, were selected and analyzed by neutron activation analysis (NAA) method. Twenty-three elements were measured. The data of these elemental contents were processed by scatter analysis and principle component analysis methods in order to determine the characteristics and sources of the raw materials of the celadon porcelain bodies from the foregoing two kilns. The results show that Fe, Ce, Ba, Ta, Th, La, Sm and Cr are the fingerprint elements to distinguish the ancient Ru official porcelain bodies from ancient celadon bodies of Zhanggongxiang kiln. The sources of the raw material of the ancient Ru official porcelain bodies from Qingliangsi kiln are more concentrated and stable than those from Zhanggongxiang kiln. The Ru folk porcelain bodies and the Ru official porcelain bodies from Qingliangsi kiln have the same provenance, both sources of which are local. The raw material origins of the ancient celadon bodies from Zhanggongxiang kiln is a little dispersed and the compositions of the raw material are different from the Ru porcelains, but the distance is not far away from each other. (authors)

  3. Neutron activation analysis of the arovenance relation of tang tri-color glazed potteryies of huangye kiln and yaozhou kiln

    International Nuclear Information System (INIS)

    Li Guoxia; Zhao Weijuan; Gao Zhengyao; Xie Jianzhong; Guo Min

    2006-01-01

    The technique of neutron activation analysis (NAA) has been employed to measure the content of 29 kinds of elements in the Tang Tri-color glazed potteryies of Huangye kiln and Yaozhou kiln. Then a fuzzy cluster analysis has been conducted to the NAA data. The results indicate that the places of origin of raw materials of body samples in the Tang Tri-color glazed potteryies of Huangye kiln are very concentrated, and that the places of origin of raw materials of body and glaze samples are scattered the places of origin of raw materials of the body and glaze raw material cover that of the body raw material. The source of raw materials of samples in the Tang Tri-color glazed potteryies of Huangye kiln is obviously different from that of samples in the Tang Tri-color glazed potteryies of Yaozhou kiln. (authors)

  4. Drying hard maple (Acer saccharum L.) lumber in a small dehumidification kiln

    Science.gov (United States)

    Neal. Bennett

    2013-01-01

    Portable sawmill owners quickly recognize the advantage to kiln drying lumber they produce. Having the ability to provide properly kiln-dried lumber opens new market opportunities and can increase profit margins. However, the construction and operation of a dry kiln must be economical and simple. A small dehumidification dry kiln constructed and tested in Princeton, WV...

  5. Evaluating a Small Structural Insulated Panel (SIP) Designed Solar Kiln in Southwestern New Mexico - Part 1

    Science.gov (United States)

    Richard D. Bergman; Ted E.M. Bilek

    2012-01-01

    With increasing energy costs, using small dry kilns for drying lumber for small-volume value-added wood products has become more of an option when compared with conventional drying. Small solar kilns are one such option, and a number of solar kiln designs exist and are in use. However, questions remain about the design and operation of solar kilns, particularly during...

  6. Thermal treatment of medical waste in a rotary kiln.

    Science.gov (United States)

    Bujak, J

    2015-10-01

    This paper presents the results of a study of an experimental system with thermal treatment (incineration) of medical waste conducted at a large complex of hospital facilities. The studies were conducted for a period of one month. The processing system was analysed in terms of the energy, environmental and economic aspects. A rotary combustion chamber was designed and built with the strictly assumed length to inner diameter ratio of 4:1. In terms of energy, the temperature distribution was tested in the rotary kiln, secondary combustion (afterburner) chamber and heat recovery system. Calorific value of medical waste was 25.0 MJ/kg and the thermal efficiency of the entire system equalled 66.8%. Next, measurements of the pollutant emissions into the atmosphere were performed. Due to the nature of the disposed waste, particular attention was paid to the one-minute average values of carbon oxide and volatile organic compounds as well as hydrochloride, hydrogen fluoride, sulphur dioxide and total dust. Maximum content of non-oxidized organic compounds in slag and bottom ash were also verified during the analyses. The best rotary speed for the combustion chamber was selected to obtain proper afterburning of the bottom slag. Total organic carbon content was 2.9%. The test results were used to determine the basic economic indicators of the test system for evaluating the profitability of its construction. Simple payback time (SPB) for capital expenditures on the implementation of the project was 4 years. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Brick-Burning Kiln from the Zhaiyk Fortified Site

    Directory of Open Access Journals (Sweden)

    Kalmenov Murat D.

    2013-12-01

    Full Text Available The article contains a description of the brick-burning kiln, which was discovered during the 2012 excavations on the medieval Zhaiyk fortified site (Western Kazakhstan oblast. A similar object had been discovered on the site in 2002. Kilns of similar design were known on the vast territories of Southeastern Europe and Central Asia in the 10th-15th cc. In the 13th-15th centuries, they were widely spread in the territory of the Golden Horde. The analysis of their design, combined with written sources and ethnographic data, allows reconstructing the operation process of such kilns in general lines. The finds of kilns on the Zhaiyk settlement make it possible to suggest that in the 13th-14th centuries there existed a developed construction materials production in the territory of the settlement.

  8. Electrical signal transfer system for a rotary kiln

    International Nuclear Information System (INIS)

    Tyson, J.H.; Kennett, L.P.; Davidson, I.S.

    1985-01-01

    A rotary kiln has a number of thermocouples respectively sensing the kiln temperature at spaced locations and respectively connected to annular slip rings. Laterally facing peripheral surfaces of the rings are respectively cooperable with brush contacts connected to a bar and a fork which embraces a ring moveable axially with the rings. Thus on longitudinal expansion of the kiln the contacts are caused to move with the rings. The electric signals from the thermocouples are thus fed to stationary monitoring equipment. In a modification the ring sections are electrically isolated and each section is connected to a respective sensor. Position sensors may be used to detect the rotary position of the kiln. The invention can be applied to other sensors. (author)

  9. 40 CFR 63.1348 - Standards for affected sources other than kilns; in-line kiln/raw mills; clinker coolers; new and...

    Science.gov (United States)

    2010-07-01

    ... than kilns; in-line kiln/raw mills; clinker coolers; new and reconstructed raw material dryers; and raw and finish mills. 63.1348 Section 63.1348 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...; in-line kiln/raw mills; clinker coolers; new and reconstructed raw material dryers; and raw and...

  10. Roller kiln with very low fluoride emission. The Ecokiln

    Energy Technology Data Exchange (ETDEWEB)

    Reymer, P.S.; Denissen, A.M. [TNO TPD Materials Research and Technology, Eindhoven (Netherlands)

    2001-09-01

    In most European countries the limit for fluoride emission in ceramic kiln flue gases is set at 5 mg HF/m{sup 3} flue gas. In cooperation with Royal Mosa, Royal Sphinx, Gasunie in the Netherlands and Sacmi, Italy, a roller kiln has been developed which can operate below the fore-mentioned limit. Also, a flue gas cleaning device is not necessary. 4 refs.

  11. Drying firewood in a temporary solar kiln: a case study.

    Science.gov (United States)

    George R. Sampson; Anthony F. Gasbarro

    1986-01-01

    A pilot study was undertaken to determine drying rates for small diameter, unsplit paper birch firewood that was dried: (1) in a conventional top-covered pile; (2) in a simple, temporary solar kiln; and (3) in tree length. Drying rates were the same for firewood piles whether they were in the temporary solar kilns or only covered on top to keep rain or snow from...

  12. Prevalence of chest symptoms amongst brick kiln migrant workers and care seeking behaviour: a study from South India.

    Science.gov (United States)

    Thomas, Beena E; Charles, Niruparani; Watson, Basilea; Chandrasekaran, V; Senthil Kumar, R; Dhanalakshmi, A; Wares, Fraser; Swaminathan, Soumya

    2015-12-01

    Early detection and treatment of tuberculosis (TB) have been key principles of TB control. However, this can be a challenge with 'hard to reach' populations such as migrants. Brick kiln workers are one such group of migrants who are exposed to smoke, heat and dust from brick kilns which are one of the major causes of respiratory illnesses. A cross-sectional community based study was carried out in Thiruvallur, Tamil Nadu, South India, from August 2011 to June 2012. A total of 4002 individuals from 55 brick kiln chambers were interviewed to determine the prevalence of chest symptoms and care seeking behaviour patterns. Three hundred and seventy-seven (9.4%) chest symptomatics were identified. The most significant variables associated with chest symptoms were illiteracy, alcohol abuse and heavy smoking. Of the chest symptomatics identified, 50.4% took action to get relief from their symptoms. The duration of over 6-month stay in the chamber was significantly associated with taking action (OR, 5.5, 95% CI: 2.3, 13.3). The TB control programme needs to further explore how to extend its services to such 'hard to reach' groups. Active case finding to ensure early diagnosis and treatment initiation amongst such groups needs consideration. © The Author 2014. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Fiscal 1999 basic survey report for promotion of joint implementation. Survey of diffusion of fluidized bed cement kilns in Vietnam; 1999 nendo Vietnam koku ni okeru ryudosho cement kiln fukyu chosa hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Possibility is assessed of energy saving and CO2 reduction through replacing shaft kilns with fluidized bed kilns at four cement plants in Vietnam. The effort will be associated with the clean development mechanism (CDM) ultimately. The fluidized bed kiln is one of the state-of-the-art technologies developed to meet social, economic, and technical demands involving global environments, enhancement of energy efficiency, effective use of resources, improvement in cost performance, increasingly diversified needs for cement, etc. Use of the technology will lead to an extensive reduction in greenhouse gas emissions, solution of the problem of dust flying from calcinating facilities, production of clinkers high in stability and quality, utilization of inexpensive fuels such as low-grade coal, and production cost reduced thanks to the new equipment occupying less installation space. The conclusion of the study is that the energy to be consumed by the four plants will decrease by 6101-9551 tons/year in terms of oil and that energy saving rate will be 37-44%. The decrease in fuel and electricity for calcinating furnaces in turn decreases CO2 emissions, with the amount of reduction estimated at 24,393-38,794 tons/year in terms of CO2 and the rate of reduction estimated at 36-44%. As for payout in case environmental special yen credit is granted, it will realize in the 10-12th year, which means such financing will achieve a sufficient investment effect. Effect is also tentatively calculated in case of fluidized bed kilns diffused across the country. (NEDO)

  14. Practical use of solar heating-dehumidification dry kiln

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Yoshinori

    1988-06-01

    In order to decrease the energy cost for drying, a solar-dehumidification dry kiln which used the dehumidification dry process together with the solar thermal drier was developed and tested. In the daytime the drying temperature rose up to 60/sup 0/C in summer and 40/sup 0/C in winter, and it was kept higher by 15 to 20/sup 0/C than the outside temperature at night. Owing to the adoption of the combination of direct solar heating and exhausting highly humid air, it was not necessary to operate the dry kiln in the day time. Average electrical energy consumption which was consumed to 15% moisture content from the raw lumber was about 73kWh/m/sup 3/ in summer which was lowest, about 87kWh/m/sup 3/ in winter. Energy cost required for the solar dehumidification dry kiln is 1/2 to 2/3 of that of the conventional dehumidification dry kiln. The solar-dehumidification dry kiln has a merit of cheaper operating cost in the low energy cost and reduced drying time. (7 figs, 1 tab, 6 refs)

  15. 40 CFR 63.1220 - What are the replacement standards for hazardous waste burning cement kilns?

    Science.gov (United States)

    2010-07-01

    ... hazardous waste burning cement kilns? 63.1220 Section 63.1220 Protection of Environment ENVIRONMENTAL... Waste Combustors Replacement Emissions Standards and Operating Limits for Incinerators, Cement Kilns... burning cement kilns? (a) Emission and hazardous waste feed limits for existing sources. You must not...

  16. Combustion of large solid fuels in cement rotary kilns

    DEFF Research Database (Denmark)

    Nielsen, Anders Rooma

    (MBM), waste wood, sewage sludge, paper and plastics. The alternative fuel share of the total energy varies significantly from region to region, but the general trend is towards increased alternative fuel utilization. Solid alternative fuels typically have physical and chemical properties that differ...... from traditional solid fossil fuels. This creates a need for new combustion equipment or modification of existing kiln systems, because alternative fuels may influence process stability and product quality. Process stability is mainly influenced by exposing the raw material bed in the rotary kiln...... oxidation is a slow process which may greatly reduce the amounts of solid fuels to be utilized in the material inlet end of rotary kilns due to the limited residence time. Several parameters control the rate of char oxidation: a) bulk oxygen concentration, b) mass transfer rate of oxygen to char particles...

  17. Analysis of Drying Process Quality in Conventional Dry-Kilns

    OpenAIRE

    Sedlar Tomislav; Pervan Stjepan

    2010-01-01

    This paper presents testing results of drying quality in a conventional dry kiln. Testing is based on a new methodology that will show the level of success of the drying process management by analyzing the quality of drying process in a conventional dry kiln, using a scientifi cally improved version of the check list in everyday practical applications. A company that specializes in lamel and classic parquet production was chosen so as to verify the new testing methodology. A total of 56 m3 of...

  18. Lime Kiln Modeling. CFD and One-dimensional simulations

    Energy Technology Data Exchange (ETDEWEB)

    Svedin, Kristoffer; Ivarsson, Christofer; Lundborg, Rickard

    2009-03-15

    The incentives for burning alternative fuels in lime kilns are growing. An increasing demand on thorough investigations of alternative fuel impact on lime kiln performance have been recognized, and the purpose of this project has been to develop a lime kiln CFD model with the possibility to fire fuel oil and lignin. The second part of the project consists of three technical studies. Simulated data from a one-dimensional steady state program has been used to support theories on the impact of biofuels and lime mud dryness. The CFD simulations was carried out in the commercial code FLUENT. Due to difficulties with the convergence of the model the calcination reaction is not included. The model shows essential differences between the two fuels. Lignin gives a different flame shape and a longer flame length compared to fuel oil. Mainly this depends on how the fuel is fed into the combustion chamber and how much combustion air that is added as primary and secondary air. In the case of lignin combustion the required amount of air is more than in the fuel oil case. This generates more combustion gas and a different flow pattern is created. Based on the values from turbulent reaction rate for the different fuels an estimated flame length can be obtained. For fuel oil the combustion is very intense with a sharp peak in the beginning and a rapid decrease. For lignin the combustion starts not as intense as for the fuel oil case and has a smoother shape. The flame length appears to be approximately 2-3 meter longer for lignin than for fuel oil based on turbulent reaction rate in the computational simulations. The first technical study showed that there are many benefits of increasing dry solids content in the lime mud going into a kiln such as increased energy efficiency, reduced TRS, and reduced sodium in the kiln. However, data from operating kilns indicates that these benefits can be offset by increasing exit gas temperature that can limit kiln production capacity. Simulated

  19. Impact of kiln thermal energy demand and false air on cement kiln flue gas CO2 capture

    Energy Technology Data Exchange (ETDEWEB)

    Arachchige, Udara S.P.R.; Kawan, Dinesh; Tokheim, Lars-Andre [Telemark University College, Porsgrunn (Norway); Melaaen, Morten C. [Telemark University College, Porsgrunn (Norway); (Tel-Tek, Porsgrunn (Norway)

    2013-07-01

    The present study is focused on the effect of the specific thermal energy demand and the false air factor on carbon capture applied to cement kiln exhaust gases. The carbon capture process model was developed and implemented in Aspen Plus. The model was developed for flue gases from a typical cement clinker manufacturing plant. The specific thermal energy demand as well as the false air factor of the kiln system were varied in order to determine the effect on CO2 capture plant performance, such as the solvent regeneration energy demand. In general, an increase in the mentioned kiln system factors increases the regeneration energy demand. The reboiler energy demand is calculated as 3270, 3428 and 3589 kJ/kg clinker for a specific thermal energy of 3000, 3400 and 3800 kJ/kg clinker, respectively. Setting the false air factor to 25, 50 or 70% gives a reboiler energy demand of 3428, 3476, 3568 kJ/kg clinker, respectively.

  20. Ring Formation in Lime Kilns; Ringbildning i Mesaugnar II

    Energy Technology Data Exchange (ETDEWEB)

    Dhak, Janice [AaF-Process AB, Stockholm (Sweden)

    2003-07-15

    The key to a cost efficient and high performance pulp production is low variations in the production level. Despite the fact that all pulp mills always work with improvements to eliminate problems with ring formations, AaF has at several mill seen that the operation of a lime kiln still often is disturbed by ring formation. In 1999 AAF made an extensive investigation of more than 10 lime kilns in Sweden, considering operational data, kiln data and lime chemical analyzes. The result pointed out the importance of how the lime kiln is operated and that dead load and contaminants in the lime was less important. The report suggested that it is the difference in the temperature between the flue gas and the lime that is of importance. There are no quantified process values available that guides for a 'best practice' way to run a lime kiln to avoid ring formation. The goal with this project has been to develop a strategy for operation of a kiln in a way that lowers the risk for ring formation. The results from simulations of a number of lime kilns in this project could not proof that a low difference in the temperature between the flue gas and the lime was the main cause of problems with ring formation and thus it was not possible to quantify the optimal difference to avoid rings. Probably the most important information from the simulations was that it is not the temperature difference in number of degrees that is of importance, rather the fact that the temperature difference in the kalcining zone varies, and time to time reach below the critical level were lime occasionally is cooled down. It can be the case if the temperature profile of the flue gas temporarily changes or if the lime mud temperature profile is changed. The reason for changes in the temperature profile is discussed in the report. The most important factors discussed are: Variations in the energy input e.g. oil and methanol/strong gases in cocombustion. One single fuel is easier to control

  1. Study of provenance properties on ancient celadon of different kilns with NAA

    International Nuclear Information System (INIS)

    Feng Songlin; Fan Dongyu; Feng Xiangqian; Xu Qing; Cheng Lin; Lei Yong; Shen Yueming; Zhang Wenjiang; Zhua Zhenxi

    2005-01-01

    Provenance characteristic is an important scientific parameter to identify ancient porcelain wares unearthed from sites and graves. The porcelain samples of Si-Long-Kou Yue kiln of Zhejiang Province, Hong-Zhou kiln of Jiangxi Province and Yao-Zhou kiln of Shanxi Province have been analyzed with neutron activation analysis (NAA). The experimental data were studied with statistic methods. The results show that the chemical compositions of porcelain body samples for three kilns were different. The difference was able to be identified. The body materials of both Si-Long-Kou Yue kiln and Hong-Zhou kiln of Jiangxi were similar. The samples of Yao-Zhou kiln in north of China existed obvious difference. (authors)

  2. Adoption of improved fish smoking kilns and recommendations in ...

    African Journals Online (AJOL)

    Adoption of improved fish smoking kilns and recommendations in North-Western Nigeria. P I Bolorunduro, O A Owolabi, O C Jegede. Abstract. No Abstract. African Journal of Livestock Extension Vol. 4 2005: pp. 89-94. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

  3. EVALUATION OF A KILN INCORPORATING AN OSCILLATING PLATE AIRFLOW SYSTEM

    OpenAIRE

    Campean,Mihaela; Marinescu,Ion; Ispas,Mihai

    2003-01-01

    Boards of spruce (Picea abies) were dried in a pilot kiln with an oscillating plate that provides -"alternating air movement in the stack". The paper outlines the airflow concept and provides results for drying time and quality.It is suggested that the system has certain advantages which make it suitable as an alternative to conventional drying, especially for small-sized enterprises

  4. PREPP [Process Experimental Pilot Plant] rotary kiln seals: Problem and resolution

    International Nuclear Information System (INIS)

    Drexler, R.L.

    1990-01-01

    The Process Experimental Pilot Plant (PREPP) is a facility designed to demonstrate processing of low level chemical and transuranic hazardous waste. The plant includes equipment for handling the incoming waste containers, shredding, incineration and cooling the waste, grouting the residue and scrubbing and filtration of the off gas. The process incinerator is a rotary kiln approximately 8-1/2 ft diameter and 25 ft long with a rotary seal assembly at each end. Each seal assembly consists of a primary, secondary and tertiary seal, with a positive air pressure between primary and secondary seals to prevent out-leakage from the kiln. The kiln operates at 0.5 inch water negative pressure. From the very outset the kiln seals exhibited excessive drag which taxed the kiln drive capacity and excessive in-leakage which limited kiln temperature. An engineering evaluation concluded that the original seals supplied by the kiln vendor could not accommodate expansion and centerline shift of the kiln resulting from heatup of the kiln and its support system. A totally new concept kiln seal design has been generated to replace the (modified) original seals. This new seal system has been designed to provide a very tight long lasting seal which will accommodate the 1.5 inch axial shift and up to 1 inch radial movement of the kiln shell. Design lifetime of the seal is 10,000 operating hours between major maintenance services while maintaining an acceptable leak rate hot or cold, rotating or stopped. The design appears adaptable to any size kiln and is suitable for retrofit to existing kilns. A one-third scale prototype seal assembly is being built to verify the concept prior to construction of the 10 ft diameter seals for the PREPP rotary kiln. 4 figs

  5. Wood Dust

    Science.gov (United States)

    Learn about wood dust, which can raise the risk of cancers of the paranasal sinuses and nasal cavity. High amounts of wood dust are produced in sawmills, and in the furniture-making, cabinet-making, and carpentry industries.

  6. Report of year 2000 version on feasibility study. Feasibility study on the diffusion of fluidized bed cement kiln system in Socialist Republic of Viet Nam

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Evaluations were given on the possibility of saving energies and reducing CO2 emission by renewing the shaft kilns operated in four factories in Viet Nam into fluidized bed kilns. The feasibility study is intended to be linked to the clean development mechanism (CDM) in the future. The fluidized bed kiln is a most advanced technology developed to deal with social, economic and technological demands such as global environment preservation, energy conservation, effective utilization of resources, enhancement of economic performance, and diversification of cement needs. The technology is capable of largely reducing greenhouse effect gases, eliminating the problem of dust scattering from sintering facilities, producing stabilized and high-quality clinker, making possible of using inexpensive fuels including low-order coal, using less installation space, and reducing the production cost. The amount of energy reduction in all of the four factories is calculated 8,101 to 9,551 toe/year at an energy saving effect rate of 37 to 44%. CO2 emission is reduced as a result of reduction in fuel for sintering furnaces and in electric power consumption. The reduction amount would be 24,393 to 38,794 tons/year (converted into CO2), and the reduction effect rate would be 36 to 44%. The investment effect looks sufficient as payout of 10 to 12 years if the environment special Yen loan is used. Trial calculation was also performed for the nation-wide proliferation effect. (NEDO)

  7. Study of provenance character on ancient porcelain of Yue Kiln at Silongkou with NAA

    International Nuclear Information System (INIS)

    Jihao Zhu; Songlin Feng; Dongyu Fan; Xiangqian Feng; Qing Xu; Yueming Shen; Zhenxi Zhuo; Wenjiang Zhang

    2007-01-01

    Chemical composition is an important information of studying the provenance character of ancient pottery and porcelain. The ancient celadon samples produced in Later Tang (850-907 A.D.) to Former Southern Song (1127-1279 A.D.) have been analyzed with NAA. Its provenance characteristic was compared with that of Hongzhou Kiln of Jiangxi Province and Yaozhou Kiln of Shanxi Province in this paper. The experimental data were studied with statistic methods. The results indicated that the chemical compositions of ancient porcelain body samples made in three kilns were different. The difference is able to be identified. The porcelain body materials of both Silongkou Yue Kiln and Hongzhou Kiln were similar. The samples of Yaozhou kiln in north of China existed obvious difference. (author)

  8. Synthetic aggregates from combustion ashes using an innovative rotary kiln.

    Science.gov (United States)

    Wainwright, P J; Cresswell, D J

    2001-01-01

    This paper describes the use of a number of different combustion ashes to manufacture synthetic aggregates using an innovative rotary 'Trefoil' kiln. Three types of combustion ash were used, namely: incinerated sewage sludge ash (ISSA); municipal solid waste incinerator bottom ash (MSWIBA-- referred to here as BA); and pulverised fuel ash (Pfa). The fine waste ash fractions listed above were combined with a binder to create a plastic mix that was capable of being formed into 'green pellets'. These pellets were then fired in a Trefoil kiln to sinter the ashes into hard fused aggregates that were then tested for use as a replacement for the natural coarse aggregate in concrete. Results up to 28 days showed that these synthetic aggregates were capable of producing concretes with compressive strengths ranging from 33 to 51 MPa, equivalent to between 73 and 112% of that of the control concrete made with natural aggregates.

  9. Combustion of solid alternative fuels in the cement kiln burner

    DEFF Research Database (Denmark)

    Nørskov, Linda Kaare

    In the cement industry there is an increasing environmental and financial motivation for substituting conventional fossil fuels with alternative fuels, being biomass or waste derived fuels. However, the introduction of alternative fuels may influence emissions, cement product quality, process...... stability, and process efficiency. Alternative fuel substitution in the calciner unit has reached close to 100% at many cement plants and to further increase the use of alternative fuels rotary kiln substitution must be enhanced. At present, limited systematic knowledge of the alternative fuel combustion...... properties and the influence on the flame formation is available. In this project a scientific approach to increase the fundamental understanding of alternative fuel conversion in the rotary kiln burner is employed through literature studies, experimental combustion characterisation studies, combustion...

  10. Integration Research on Gas Turbine and Tunnel Kiln Combined System

    Science.gov (United States)

    Shi, Hefei; Ma, Liangdong; Liu, Mingsheng

    2018-04-01

    Through the integrated modeling of gas turbine and tunnel kiln combined system, a thermodynamic calculation method of combined system is put forward, and the combined system operation parameters are obtained. By this method, the optimization of the combined system is analyzed and the optimal configuration of the gas turbine is calculated. At the same time, the thermal efficiency of the combined system is analyzed, and the heat distribution and thermal efficiency of the system before and after the improvement are explained. Taking the 1500 kg/h ceramic production as an example, pointed out that if the tunnel kiln has a gas turbine with a power of 342 kw. The amount of electricity of the combined system that produced per unit volume of the fuel which consumes more than it used to will be 7.19 kwh, the system thermal efficiency will reach 57.49%, which higher than the individual gas turbine’s cycle thermal efficiency 20% at least.

  11. Performance of rotary kiln reactor for the elephant grass pyrolysis.

    Science.gov (United States)

    De Conto, D; Silvestre, W P; Baldasso, C; Godinho, M

    2016-10-01

    The influence of process conditions (rotary speed/temperature) on the performance of a rotary kiln reactor for non-catalytic pyrolysis of a perennial grass (elephant grass) was investigated. The product yields, the production of non-condensable gases as well as the biochar properties were evaluated. The maximum H2 yield was close to that observed for catalytic pyrolysis processes, while the bio-oil yield was higher than reported for pyrolysis of other biomass in rotary kiln reactors. A H2/CO ratio suitable for Fischer-Tropsch synthesis (FTS) was obtained. The biochars presented an alkaline pH (above 10) and interesting contents of nutrients, as well as low electrical conductivity, indicating a high potential as soil amendment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. 1998 data bank for kiln-dried red oak lumber

    Science.gov (United States)

    Charles J. Gatchell; R. Edward Thomas; Elizabeth S. Walker

    1998-01-01

    A collection of 3,487 fully described, kiln-dried red oak boards totaling 20,021 board feet. The boards, which are straight or contain no more than ? inch of crook, are FAS, FAS ONE FACE (F1F), Selects, No. 1 Common, No. 2A Common, or No. 3A common. The boards were graded with the UGRS (Ultimate Grading and Remanufacturing System) computer program. After the grade was...

  13. Design of a Rotary Kiln for Production of Sarooj

    Directory of Open Access Journals (Sweden)

    A. W. Hago

    2008-12-01

    Full Text Available Sarooj is a local term used for pozzolana. It has been used extensively as a hydraulic binder in buildings, hydraulic installations, forts and castles, and in the renovation of historical monuments. It is produced by burning specific clay soil that possesses adequate quantities of silica, alumina and iron oxides. In the past, the material was produced using a large amount of energy most of which is wasted by blowing winds. The burning system was usually thermally inefficient, and the output is rarely checked for quality. Test on products produced by using the traditional method may yield poor quality Sarooj due to inadequate burning or over burning or even insufficient grinding in the end. In this research, extensive experimentation has been performed on the method of production of Sarooj to determine the factors influencing Sarooj quality. Based on these factors, a new method of production is proposed. In this method, a fully mobile kiln was designed to produce Sarooj on the site. The kiln can produce 200 kg/h of Sarooj, and can be installed within one hour of arriving on the site. It can be towed by a tractor or a normal vehicle to the desired location, connected to the natural gas supply and the electric power. The construction is light, compact, and easy to start and shut down. In this paper, the plant is described in detail, together with some preliminary results of testing done on Sarooj produced by the kiln. Full details of tests on the product of the kiln will be given in a subsequent paper.

  14. Volume loss as a tool to assess kiln drying of eucalyptus wood

    OpenAIRE

    Batista,Djeison Cesar; Klitzke,Ricardo Jorge; Rocha,Márcio Pereira da; Muñiz,Graciela Inez Bolzon de; Batista,Tharcia Ribeiro

    2013-01-01

    In this study, we aimed to analyze the kiln drying quality of Eucalyptus grandis, Eucalyptus saligna and Eucalyptus dunnii woods with respect to volume loss. Wood from the three species was kiln dried together with the same drying schedule and conditions in a conventional-temperature pilot kiln. Three kinds of volume loss were evaluated: total - from saturated (initial) to machined (final) condition; shrinkage - from saturated to 10% moisture content; and machining - from 10% moisture content...

  15. Moessbauer Study of a Celtic Pottery-Making Kiln in Lower Bavaria

    International Nuclear Information System (INIS)

    Gebhard, R.; Guggenbichler, E.; Haeusler, W.; Riederer, J.; Schmotz, K.; Wagner, F. E.; Wagner, U.

    2004-01-01

    In 1995 a well preserved 3rd century BC Celtic kiln for pottery making was excavated at Schmiedorf in Lower Bavaria. The firing chamber and the flue plate of the kiln were preserved, whereas the dome was not found. We report on a study of material from this kiln by neutron activation analysis, thin-section microscopy, X-ray diffraction and Moessbauer spectroscopy, all performed with the aim to learn more about pottery-making procedures in Celtic times.

  16. Leaching from waste incineration bottom ashes treated in a rotary kiln

    DEFF Research Database (Denmark)

    Hyks, Jiri; Nesterov, Igor; Mogensen, Erhardt

    2011-01-01

    Leaching from municipal solid waste incineration bottom ash treated in a rotary kiln was quantified using a combination of lab-scale leaching experiments and geochemical modelling. Thermal treatment in the rotary kiln had no significant effect on the leaching of Al, Ba, Ca, Mg, Si, Sr, Zn, sulfate...... the thermal treatment. Overall, rotary kiln thermal treatment of bottom ashes can be recommended to reduce the leaching of Cu, Pb, Cl and DOC; however, increased leaching of Cr and Mo should be expected....

  17. Gasification of sulphate soap for the lime kiln

    Energy Technology Data Exchange (ETDEWEB)

    Saviharju, Kari (Valtion Teknillinen Tutkimuskeskus, Espoo (Finland). Lab. of Fuel and Process Technology); Timonen, Tuomas (Finnish Energy Economy Association, Espoo (Finland). Finnish Recovery Boiler Committee)

    1993-01-01

    Sulphate soap is a by-product of pulp mills utilized as a raw material for the chemical industry. However, this results in an increase in sulphur input of several kilograms SO[sub 2] per ADt pulp into the mill. Another increasingly interesting alternative is to utilize soap in the lime kiln of the mill. This has a positive effect, in addition to sulphur problems, on the energy balance of the mill. The crucial problem is the high Na + K content of soap, from 4 to 8%, which can result in plugging of the lime kiln. The operational problems can be avoided by gasifying the soap and by separating the inorganic materials from the product gas before the kiln. This paper describes research work on the gasification of crude sulphate soap carried out at the Technical Research Centre of Finland (VTT) over the years 1991 and 1992. This work will be continued in 1993 by focusing on specified problems, after which commercial applications should be available. (author)

  18. Lignite chemical conversion in an indirect heat rotary kiln gasifier

    Directory of Open Access Journals (Sweden)

    Hatzilyberis Kostas S.

    2006-01-01

    Full Text Available The results on the gasification of Greek lignite using two indirect heat (allothermal pilot rotary kiln gasifiers are reported in the present work. The development of this new reactor-gasifier concept intended for solid fuels chemical conversion exploits data and experience gained from the following two pilot plants. The first unit A (about 100 kg/h raw lignite demonstrated the production of a medium heating value gas (12-13 MJ/Nm3 with quite high DAF (dry ash free coal conversions, in an indirect heat rotary gasifier under mild temperature and pressure conditions. The second unit B is a small pilot size unit (about 10 kg/h raw lignite comprises an electrically heated rotary kiln, is an operation flexible and exhibits effective phase mixing and enhanced heat transfer characteristics. Greek lignite pyrolysis and gasification data were produced from experiments performed with pilot plant B and the results are compared with those of a theoretical model. The model assumes a scheme of three consecutive-partly parallel processes (i. e. drying, pyrolysis, and gasification and predicts DAF lignite conversion and gas composition in relatively good agreement with the pertinent experimental data typical of the rotary kiln gasifier performance. Pilot plant B is currently being employed in lime-enhanced gasification studies aiming at the production of hydrogen enriched synthesis gas. Presented herein are two typical gas compositions obtain from lignite gasification runs in the presence or not of lime. .

  19. Cometary Dust

    Science.gov (United States)

    Levasseur-Regourd, Anny-Chantal; Agarwal, Jessica; Cottin, Hervé; Engrand, Cécile; Flynn, George; Fulle, Marco; Gombosi, Tamas; Langevin, Yves; Lasue, Jérémie; Mannel, Thurid; Merouane, Sihane; Poch, Olivier; Thomas, Nicolas; Westphal, Andrew

    2018-04-01

    This review presents our understanding of cometary dust at the end of 2017. For decades, insight about the dust ejected by nuclei of comets had stemmed from remote observations from Earth or Earth's orbit, and from flybys, including the samples of dust returned to Earth for laboratory studies by the Stardust return capsule. The long-duration Rosetta mission has recently provided a huge and unique amount of data, obtained using numerous instruments, including innovative dust instruments, over a wide range of distances from the Sun and from the nucleus. The diverse approaches available to study dust in comets, together with the related theoretical and experimental studies, provide evidence of the composition and physical properties of dust particles, e.g., the presence of a large fraction of carbon in macromolecules, and of aggregates on a wide range of scales. The results have opened vivid discussions on the variety of dust-release processes and on the diversity of dust properties in comets, as well as on the formation of cometary dust, and on its presence in the near-Earth interplanetary medium. These discussions stress the significance of future explorations as a way to decipher the formation and evolution of our Solar System.

  20. Increased Coal Replacement in a Cement Kiln Burner by Feeding a Mixture of Solid Hazardous Waste and Shredded Plastic Waste

    OpenAIRE

    Ariyaratne, W. K. Hiromi; Melaaen, Morten Christian; Tokheim, Lars-André

    2013-01-01

    The present study aims to find the maximum possible replacement of coal by combined feeding of plastic waste and solid hazardous waste mixed with wood chips (SHW) in rotary kiln burners used in cement kiln systems. The coal replacement should be achieved without negative impacts on product quality, emissions or overall operation of the process. A full-scale experiment was carried out in the rotary kiln burner of a cement kiln by varying SHW and plastic waste feeding rates. Experimental result...

  1. MECHANISMS GOVERNING TRANSIENTS FROM THE BATCH INCINERATION OF LIQUID WASTES IN ROTARY KILNS

    Science.gov (United States)

    When "containerized" liquid wastes, bound on sorbents. are introduced into a rotary kiln in a batch mode, transient phenomena in-volving heat transfer into, and waste mass transfer out of, the sorbent can oromote the raoid release of waste vaoor into the kiln environment. This ra...

  2. Design and operation of a solarheated dry kiln for tropical latitudes

    Science.gov (United States)

    Brian Bond; Omar Espinoza; Philip Araman

    2011-01-01

    Lumber is usually dried to a specific moisture content prior to further manufacturing or use. While lumber can be air-dried, the ambient humidity in most localities prevents the lumber from reaching the moisture content necessary for dimensional stability and use, especially for interior use. Solar kilns are an inexpensive alternative to conventional steam-heated kilns...

  3. Study on provenance of Ru porcelain in yanhedian kiln and official jun porcelain by EDXRF

    International Nuclear Information System (INIS)

    Li Guoxia; Guo Min; Zhao Weijuan; Sun Hongwei; Gao Zhengyao; Xie Jianzhong; Wen Chang; Wang Chuan; Li Rongwu; Guo Peiyu; Yang Dawei

    2010-01-01

    To understand the provenance relationship of Ru porcelain in Yanhedian kiln and official Jun porcelain , with energy dispersive x-ray fluorescence spectrometer (EDXRF) measured 56 Ru porcelain in Yanhedian kiln and official Jun porcelain samples of chemical composition of the main volume, analysis results show: Yanhedian kiln Ru porcelain bodies Al 2 O 3 average content Outpaces official Jun porcelain bodies, SiO 2 , K 2 O average below official Jun porcelain bodies; Yanhedian kiln Ru porcelain glazes Al 2 O 3 average content Outpaces official Jun porcelain glaze, SiO 2 , CaO average significantly lower than Jun glaze, two primary body and glaze on porcelain to chemical composition of the averages vary. A display of the peacekeeping two-dimensional scatter analysis supplies of official Jun porcelain bodies focused, Yanhedia kiln Ru porcelain bodies birth supplies comparatively, Jun and Yanhedian kiln Ru porcelain bodies material habitats near but not identical. The official Jun porcelain glazes origin focused, glaze formula changes less, and Yanhedia kiln Ru porcelain glazes origin and formula are scattered. Therefore, Yanhedian kiln Ru porcelain samples and the Official Jun porcelain samples can be commendably differentiated by EDXRF testing and chemical composition scatter analysis. (authors)

  4. Manual of design and installation of Forest Service water spray dry kiln

    Science.gov (United States)

    L.V. Teesdale

    1920-01-01

    The best thing that can be said of any dry kiln is that when it is run by a properly informed operator the temperature, humidity, and circulation are constant and uniform. In an endeavor to produce a kiln in which each of these could be regulated independently of the others, the Forest Products Laboratory designed and developed the "Forest Service Humidity...

  5. A Thermoelectric Waste-Heat-Recovery System for Portland Cement Rotary Kilns

    Science.gov (United States)

    Luo, Qi; Li, Peng; Cai, Lanlan; Zhou, Pingwang; Tang, Di; Zhai, Pengcheng; Zhang, Qingjie

    2015-06-01

    Portland cement is produced by one of the most energy-intensive industrial processes. Energy consumption in the manufacture of Portland cement is approximately 110-120 kWh ton-1. The cement rotary kiln is the crucial equipment used for cement production. Approximately 10-15% of the energy consumed in production of the cement clinker is directly dissipated into the atmosphere through the external surface of the rotary kiln. Innovative technology for energy conservation is urgently needed by the cement industry. In this paper we propose a novel thermoelectric waste-heat-recovery system to reduce heat losses from cement rotary kilns. This system is configured as an array of thermoelectric generation units arranged longitudinally on a secondary shell coaxial with the rotary kiln. A mathematical model was developed for estimation of the performance of waste heat recovery. Discussions mainly focus on electricity generation and energy saving, taking a Φ4.8 × 72 m cement rotary kiln as an example. Results show that the Bi2Te3-PbTe hybrid thermoelectric waste-heat-recovery system can generate approximately 211 kW electrical power while saving 3283 kW energy. Compared with the kiln without the thermoelectric recovery system, the kiln with the system can recover more than 32.85% of the energy that used to be lost as waste heat through the kiln surface.

  6. Effect of cement dust pollution on certain physical parameters of maize crop and soils

    Energy Technology Data Exchange (ETDEWEB)

    Parthasarathy, S; Arunachalam, N; Natarajan, K; Oblisami, G; Rangaswami, G

    1975-04-01

    A study was undertaken in the fields near a cement factory where the cement dust is the prime pollutant to the field crops and soils. Cement dust deposit varied with the distance from the kiln and fourth and fifth leaves of maize had comparatively more dust than the first three leaves from the top. The cement dust deposited plants showed a suppression in most of the characters like leaf size, number and size of cobs and plant height when compared to plants in non-polluted fields. On comparison with the physical characters of the soils from the control field the soil from cement dust polluted field showed a decrease in water holding capacity and pore space while thermal conductivity and specific heat were more. Artificial mixtures of red and black soils with cement dust showed similar trend as those of the field sample, the black soil being affected more seriously than the red soil.

  7. Metals partitioning resulting from rotary kiln incineration of hazardous waste

    International Nuclear Information System (INIS)

    Richards, M.K.; Fournier, D.J. Jr.

    1992-01-01

    In response to the need for date on the partitioning of trace metals from hazardous waste incinerators, an extensive series of test was conducted in the summer of 1991 at the USEPA Incineration Research Facility (IRF) in Jefferson, Arkansas. These tests were conducted in the IRF's rotary kiln incinerator system (RKS) equipped with a pilot-scale Calvert Flux-Force/Condensation scrubber as the primary air pollution control system (APCS). The purpose of this test series was to extend the data base on trace metal partitioning and to investigate the effects of variations in incinerator operation on metal partitioning. Another objective was to evaluate the effectiveness of the scrubber for collecting flue gas metals. This series is a continuation of an ongoing IRF research program investigating trace metal partitioning and APCS collection efficiencies. Two previous test series were conducted using the RKS equipped with a venturi/packed-column scrubber and a single-state ionizing wet scrubber. The primary objective of this test series was to determine the fate of six hazardous and four nonhazardous trace metals fed to the RKS in a synthetic, organic-contaminated solid waste matrix. The six hazardous trace metals used were arsenic, barium, cadmium, chromium, mercury, and lead. The four nonhazardous trace metals--bismuth, copper, magnesium, and strontium--were included primarily to supply data to evaluate their potential for use as surrogates. The temperature, waste feed chlorine content, and scrubber pressure drop. The test program objectives were to identify. The partitioning of metals among kiln ash, scrubber liquor, and flue gas. Changes in metal partitioning related to variations in kiln exit gas temperature and waste feed chlorine content. The efficiency of the Calvert scrubber for collecting flue gas metals. The effects of scrubber pressure drop on metal collection efficiencies. 2 figs., 2 tabs

  8. Volume loss as a tool to assess kiln drying of eucalyptus wood

    Directory of Open Access Journals (Sweden)

    Djeison Cesar Batista

    Full Text Available In this study, we aimed to analyze the kiln drying quality of Eucalyptus grandis, Eucalyptus saligna and Eucalyptus dunnii woods with respect to volume loss. Wood from the three species was kiln dried together with the same drying schedule and conditions in a conventional-temperature pilot kiln. Three kinds of volume loss were evaluated: total - from saturated (initial to machined (final condition; shrinkage - from saturated to 10% moisture content; and machining - from 10% moisture content to machined condition. Eucalyptus grandis wood was the most dimensionally stable and presented the smallest volume loss due to shrinkage. Although they had different shrinkage behaviors, Eucalyptus grandis and Eucalyptus saligna woods presented the same drying quality regarding machining and total volume losses. These species can be considered the same for kiln drying. Eucalyptus dunnii wood presented the worst quality in drying, and should not be kiln dried in the same batch with the other species.

  9. Allergies, asthma, and dust

    Science.gov (United States)

    Reactive airway disease - dust; Bronchial asthma - dust; Triggers - dust ... Things that make allergies or asthma worse are called triggers. Dust is a common trigger. When your asthma or allergies become worse due to dust, you are ...

  10. Baking of the multi-itemed clinker by the large kiln; Ogata kirun ni yoru tahinshu kurinka no shosei

    Energy Technology Data Exchange (ETDEWEB)

    Kihara, Yasuhiro [Ube Industies, Ltd., Yamaguchi (Japan)

    1998-10-10

    In the Ube cement plant, it had 5 DB kilns, and it became a base of the special cement manufacture. However, the productivity difference with the special cement manufacture by the large kiln recently spread, and in the DB cairn, it was judged with the limit. Therefore, the rationalization which put together DB kiln of 5 in NSP kiln of 1 was carried out, while the role of the special cement manufacture base was maintained. In this paper, the outline of variety switching technology in large and single kiln of 1 for the multi-itemed and multi-itemed clinker production is introduced in this. (NEDO)

  11. Effect of cement kiln dust and gamma irradiation on the ultrasonic parameters of HMO borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Abd elfadeel, G. [Physics Department, Faculty of Science, Al-Azhar University, Assiut 71524 (Egypt); Saddeek, Yasser B., E-mail: ysaddeek@gmail.com [Physics Department, Faculty of Science, Al-Azhar University, Assiut 71524 (Egypt); Mohamed, Gehan Y. [Experimental Nuclear Physics Department, Nuclear Research Center, Atomic Energy Authority, Post Office No. 13759, Cairo (Egypt); Mostafa, A.M.A. [Physics Department, Faculty of Science, Al-Azhar University, Assiut 71524 (Egypt); Shokry Hassan, H. [Advanced Technology and New Materials Research Institute, City of Scientific Research and Technology Applications, New Borg El-Arab City, Alexandria 21934 (Egypt)

    2017-03-01

    Glass samples with the chemical formula x CKD—(100 − x) (5Na{sub 2}O–65 B{sub 2}O{sub 3}–9 Bi{sub 2}O{sub 3}–21PbO), (0 ⩽ x ⩽ 32 mol%) were prepared. The density and the ultrasonic estimations of the investigated glasses were analyzed at room temperature before and after the impact of two dosages of gamma irradiation to study the effect of both CKD and gamma radiation. It was found that the density, and the ultrasonic parameters are sensitive to the variety of the content of CKD and the effect of γ-radiation. Replacement of oxides with higher atomic weights such as Bi{sub 2}O{sub 3} and PbO by CKD decreases the density. Analysis of the behavior of the ultrasonic parameters demonstrates that creation of CaO{sub 6} and SiO{sub 4} on one hand and an alternate transformation between BO{sub 4} and BO{sub 3} structural units, on the other hand, affect the increase of the ultrasonic velocities and the elastic moduli. Moreover, the density and the ultrasonic parameters decrease somewhat with the increase of the doses of γ-irradiation. The variations of the previous physical parameters can be referred to the creation of radiation imperfections, which occupied the voids inside the glass structure.

  12. Effect of cement kiln dust and gamma irradiation on the ultrasonic parameters of HMO borate glasses

    Science.gov (United States)

    Abd elfadeel, G.; Saddeek, Yasser B.; Mohamed, Gehan Y.; Mostafa, A. M. A.; Shokry Hassan, H.

    2017-03-01

    Glass samples with the chemical formula x CKD-(100 - x) (5Na2O-65 B2O3-9 Bi2O3-21PbO), (0 ⩽ x ⩽ 32 mol%) were prepared. The density and the ultrasonic estimations of the investigated glasses were analyzed at room temperature before and after the impact of two dosages of gamma irradiation to study the effect of both CKD and gamma radiation. It was found that the density, and the ultrasonic parameters are sensitive to the variety of the content of CKD and the effect of γ-radiation. Replacement of oxides with higher atomic weights such as Bi2O3 and PbO by CKD decreases the density. Analysis of the behavior of the ultrasonic parameters demonstrates that creation of CaO6 and SiO4 on one hand and an alternate transformation between BO4 and BO3 structural units, on the other hand, affect the increase of the ultrasonic velocities and the elastic moduli. Moreover, the density and the ultrasonic parameters decrease somewhat with the increase of the doses of γ-irradiation. The variations of the previous physical parameters can be referred to the creation of radiation imperfections, which occupied the voids inside the glass structure.

  13. Development of a three-dimensional CFD model for rotary lime kilns

    Energy Technology Data Exchange (ETDEWEB)

    Lixin Tao; Blom, Roger (FS Dynamics Sweden AB, Goeteborg (Sweden)); Nordgren, Daniel (Innventia, Stockholm (Sweden))

    2010-11-15

    In the calcium loop of the recovery cycle in a Kraft process of pulp and paper production, rotary lime kilns are used to convert the lime mud, mainly CaCO3, back to quick lime, CaO, for re-use in the causticizing process. The lime kilns are one of the major energy consumption devices for paper and pulp industry. Because of the rising oil price and new emission limits, the pulp mills have been forced to look for alternative fuels for their lime kilns. One interesting alternative to oil, often easily available at pulp mills, is biofuels such as sawdust and bark. However the practical kiln operation often encounters some difficulties because of the uncertainties around the biofuel impact on the lime kiln performance. A deeper understanding of the flame characteristics is required when shifting from oil to biofuels. Fortunately recent advances in modern Computational Fluid Dynamics, CFD, have provided the possibility to study and predict the detailed flame characteristics regarding the lime kiln performance. In this project a three-dimensional CFD model for rotary lime kilns has been developed. To simulate a rotary lime kiln the developed CFD model integrates the three essential sub-models, i.e. the freeboard hot flow model, the lime bed model and the rotating refractory wall model and it is developed based on the modern CFD package: FLUENT which is commercially available on the market. The numerical simulations using the developed CFD model have been performed for three selected kiln operations fired with three different fuel mixtures. The predicted results from the CFD modelling are presented and discussed in order to compare the impacts on the kiln performance due to the different firing conditions. During the development, the lime kiln at the Soedra Cell Moensteraas mill has been used as reference kiln. To validate the CFD model, in-plant measurements were carried out in the Moensteraas lime kiln during an experiment campaign. The results obtained from the

  14. ANALISIS EFISIENSI PANAS TUNNEL KILN PADA PT XYZ DENGAN NERACA MASSA DAN ENERGI

    Directory of Open Access Journals (Sweden)

    Tri Ngudi Wiyatno

    2017-10-01

    ABSTRACT One of the process that can’t be missed to make a ceramic tile is burning. PT XYZusing tunnel kiln with LNG fuel for burning process. The purpose of this research is to know how much heat efficiency of tunnel kiln with firstly calculated mass balance and heat balance at burning ceramics tile. Data for incoming heat are obtain from calculated of heat burning fuel, sensible heat of LNG, incoming heat from kiln car and sensible heat green tile. Data for outgoing heat are obtain from calculated of sensible heat ceramic tile, sensible heat kiln car, evaporation heat of water and water crystal, heat loss because cooling air, heat of burning, heat for dryer, heat for chimney fan, and heat loss because heat transfer. The method that we used for this research are Consumption of Volume LNG, composition material tile, composition part of tunnel kiln like kiln car and heat capacity for each component. Based on the data we can obtained heat balance in and out kiln amount14.174.025 kkal/day. And the LNG fuel efficiencyis calculated by comparison between the heat generated from the fuel and the heat requirement used for one dayceramic tile burning process. After the calculation we can obtained the efficiencyis 98,92%. Keywords: Efficiency, Ceramic Tile, Mass Balance, Heat Balance, Burning.

  15. Improvement of cement plant dust emission by bag filter system

    Science.gov (United States)

    Wahyu Purnomo, Chandra; Budhijanto, Wiratni; Alfisyah, Muziibu; Triyono

    2018-03-01

    The limestone quarry in PT Indocement Tunggal Prakarsa (ITP) in Cirebon is considered as a complex quarry in terms of chemical composition and material hardness. From the beginning of the plant operation up to the end of 2015, the dust removal was rely on electrostatic precipitator (EP) system. Whenever limestone from specific quarry zones were incorporated into Raw Mill (RM) feed or there was an upset condition, the dust emission increased significantly. Beside higher demand of electricity, an EP system requires lower gas inlet temperature in order to remove the dust effectively which requires larger cooling water in the previous gas conditioning tower to cool down gas from 400 °C to about 100 °C. By considering the drawbacks, the EP system was replaced by a bag filter (BF) system. The BF allows higher temperature of gas inlet and it has higher dust removal efficiency. In this study, the efficiency of the two different dust removal systems is compared. The effect of process variables i.e. RM feed, kiln feed, inlet temperature and pressure, and small size particle fraction to the dust emission are studied by multivariate linier regression analysis. It is observed that the BF system can reduce significantly the dust emission from 30 to 6 mg/m3 and in the same time reducing CO2 emission by 0.24 ton/year from the electricity consumption saving.

  16. The System of Simulation and Multi-objective Optimization for the Roller Kiln

    Science.gov (United States)

    Huang, He; Chen, Xishen; Li, Wugang; Li, Zhuoqiu

    It is somewhat a difficult researching problem, to get the building parameters of the ceramic roller kiln simulation model. A system integrated of evolutionary algorithms (PSO, DE and DEPSO) and computational fluid dynamics (CFD), is proposed to solve the problem. And the temperature field uniformity and the environment disruption are studied in this paper. With the help of the efficient parallel calculation, the ceramic roller kiln temperature field uniformity and the NOx emissions field have been researched in the system at the same time. A multi-objective optimization example of the industrial roller kiln proves that the system is of excellent parameter exploration capability.

  17. Provenance and dating study on Jianyao Kiln porcelain bodies using NAA and WDXRF

    International Nuclear Information System (INIS)

    Feng Xiangqian; Feng Songlin; Li Jian'an; Li Dejin

    2007-01-01

    In order to distinguish provenance and age of Jianyao Kiln porcelains based on their chemical composition, 139 sherds that cover seven periods of production, were collected from three kiln sites. Trace and major elements in their body samples were determined by NAA and WDXRF, respectively. The analytical data and statistical analysis results show that all the body samples can be classified into 4 groups, i.e. Late Tang and Five Dynanties, Northern Song, Southern Song and Yuan. The raw materials adopted by Daluhoumen kiln site black porcelains were similar to those of Yingzhangqian site, but quite different from those of Anweishan site. (authors)

  18. Study on Hongzhou kiln porcelains of successive dynasties by NAA

    International Nuclear Information System (INIS)

    Feng Xiangqian; Feng Songlin; Quan Kuishan

    2005-01-01

    400 sherds were collected from Hongzhou Kiln covering 8 periods from Eastern Han to Late Tang Dynasty/the Five Dynasties and their bodies were analysed by NAA. The results show that the elemental contents in different samples are quite distinct, even for those in the same period. It means no single element can be used as 'fingerprint' to distinguish the period. The curves of the contents of Na, Rb, Ba and Fe varying with time are very similar, like 'U' shape. As a colorant element, the content of Fe is consistent with the color of the body. The higher content of Fe is, the more dark of the body is. The outcome of principal component analysis (PCA) indicates that most of the sherds can be classified into 5 groups: (1) Eastern Han and Eastern Wu; (2) Western Jin, Eastern Jin and Southern Dynasties; (3) Sui; (4) Early Tang and Middle Tang; (5) Late Tang and Five Dynasties. (authors)

  19. Sulfur Release during Alternative fuels Combustion in Cement Rotary Kilns

    DEFF Research Database (Denmark)

    Cortada Mut, Maria del Mar

    fuel with the bed material, heating up of a particle, 5 iv devolatilization, char combustion, the reactions between CaSO 4 and the different reducing agents, and the oxidation of the volatiles gases in the free board. The main reducing agents are CO, CH 4 and H 2 , which are introduced under the bed...... are of high importance for SO 2 release because it is shown that introducing the same total amount of gas, the highest reducing agent concentration fo r a short period released a higher total SO 2 amount compared to the lowest concentration during a long period. A mathematical reaction based model...... but the effect of sulfur content in the bed cannot be predicted. Further development regarding particle motion according to the rotational speed may be needed. Furthermore, a model for predicting the tendency of build-ups for a kiln system is developed based on the prediction of SO 3 and Cl concentrations...

  20. Development of a Metal Kiln for the Production of Charcoal from ...

    African Journals Online (AJOL)

    African Journal of Sustainable Development ... The study established that the design upon modification would be environmentally safe, viable and an economic alternative for ... Keywords: Production, Smoking, Charcoal, Kiln, Design ...

  1. Imaging of Flames in Cement Kilns To Study the Influence of Different Fuel Types

    DEFF Research Database (Denmark)

    Pedersen, Morten Nedergaard; Nielsen, Mads; Clausen, Sønnik

    2017-01-01

    The cement industry aims to use an increased amount of alternative fuels to reduce production costs and CO2 emissions. In this study three cement plants firing different kinds and percentages of alternative fuel were studied. A specially developed camera setup was used to monitor the flames...... in the three cement kilns and assess the effect of alternative fuels on the flame. It was found that cofiring with solid recovered fuel (SRF) would delay the ignition point by about 2 m and lower the intensity and temperature of the kiln flame compared to a fossil fuel flame. This is related to a larger...... particle size and moisture content of the alternative fuels, which lowers the conversion rate compared to fossil fuels. The consequences can be a lower kiln temperature and cement quality. The longer conversion time may also lead to the possibility of localized reducing conditions in the cement kiln, which...

  2. Insulation performance data and assessment procedures for steam kiln energy conservation investments

    Energy Technology Data Exchange (ETDEWEB)

    Zaccor, J.V.

    1980-09-01

    For a demonstration project, the costs and benefits of insulating concrete block curing kilns to isolate the kiln thermal mass from the curing cycle are determined. Data were developed on service life of FOAMGLAS insulation, the effect of Johnson burners on the insulation and mounting, performance of an alternative insulation (a rapidly installed, spray-on polyurethane foam), and a simple incentive to promote implementation of industrial energy conservation concepts. Data are tabulated and compared for the FOAMGLAS and CPR 480 polyurethane insulations. Specific studies of insulation that was installed on inside surfaces of kilns to lock the kiln-mass out of the curing cycle are given for Blocklite plant in California, the Ameron pipe plant in California, and the Superlite plant in Phoenix, Arizona. (MCW)

  3. Better lumber drying process with a non-greenhouse type solar kiln

    Energy Technology Data Exchange (ETDEWEB)

    Yang, K C

    1979-01-01

    The preliminary study of using solar energy for lumber drying in NW Ontario is proven applicable and practical by the evidence of data collected. It was found that lumber seasoning using solar energy in the region is more favorable in the summer than in the winter. The most significant advantages of lumber drying with a solar kiln are: (1) low percentage of drying defect lumber produced; (2) higher strength properties of lumber produced; (3) unlimited sources of heat energy from the sun are available. The longer drying periods with a solar kiln as compared to a conventional steam kiln can be overcome by utilizing a supplemental heat system, e.g., wood residue burner to shorten the drying period. However, some improvements and modification of the existing kiln should be done in order to increase the efficiency of the lumber drying system.

  4. Evaluation of kiln-drying schedules for wild cherry wood (Cerasus avium)

    OpenAIRE

    Korkut, Süleyman; Ünsal, Öner; Kocaefe, Duygu; Aytin, Ayhan; Gökyar, Asli

    2013-01-01

    Wild cherry wood (Cerasus avium (L.) Monench) lumber with a nominal thickness of 5 cm from Duzce region in Turkey was dried through conventional kiln drying using two different programs which are unprotective drying schedules, and protective drying schedules. The aim was to obtain the most desirable kiln schedule for keeping the wood quality at an appropriate level up to final moisture content of 12±2% was reached. Intensity of warping (twist, bow, cup, crook) occurrence, superficial, interna...

  5. Controlled-air and rotary-kiln proof-of-principle tests

    International Nuclear Information System (INIS)

    Hedahl, T.G.

    1982-05-01

    Although the incinerator tests did not represent optimized processing, general system design characteristics were established. The test results indicated that the rotary kiln incinerator would be most applicable in the Transuranic Waste Treatment Facility (TWTF) for the following reasons: (1) The rotary kiln is more capable of achieving near-complete combustion of the combustibles in the waste mixed with a high proportion of metal and noncombustible waste. Complete combustion of the combustible waste is preferred in order to reduce waste volume and ensure the production of a stable, immobilized waste form. (2) The rotary kiln processing appears to be more flexible. Kiln rotation rate, kiln incline, and waste feed rate and method are system variables which can be altered to meet the needs of processing variable waste compositions. The advantages of the rotary kiln system allow for a practical concept for processing a majority of the radioactive waste at the INEL. However, further engineering tests must be performed to determine the necessary processing angles and design information for TWTF waste processing

  6. Cement factory kilns. Clinker baking workshops; Fours de cimenterie. Ateliers de cuisson du clinker

    Energy Technology Data Exchange (ETDEWEB)

    Bastier, R. [Direction Centrale Technologie (France); Bocan, A.; Gerbert, B.; Regnault, A.

    2000-07-01

    Clinker baking is the intermediate of the three main steps of the cement fabrication process. The aim of the baking workshop is the thermal transformation of the crude material into a semi-product (clinker). The problem of clinker baking is to find the optimum process taking into account: the investment and operation costs,the diversity of raw materials and fuels, the socio-economical constraints, the performances required, the environmental constraints and the increase of production capacity. This paper gives a presentation of the different types of clinker baking workshops: 1 - Rotative kiln and baking workshop; 2 - Different types of baking workshops: general considerations, humid way process (long kiln - WL), half-dry way process (short kiln - DG-N), dry-way process (short kiln - DS-X), comparison of standard energy consumptions and production ratios; 3 - Pre-calcination (DS-X-SF and DS-X-PC kilns): general considerations, industrial realizations, operation of pre-calcination, characteristics, advantages and drawbacks, standard operation data; 4 - Dimensioning of dry-way kilns: theoretical and empirical methods. (J.S.)

  7. Numerical analysis of an entire ceramic kiln under actual operating conditions for the energy efficiency improvement.

    Science.gov (United States)

    Milani, Massimo; Montorsi, Luca; Stefani, Matteo; Saponelli, Roberto; Lizzano, Maurizio

    2017-12-01

    The paper focuses on the analysis of an industrial ceramic kiln in order to improve the energy efficiency and thus the fuel consumption and the corresponding carbon dioxide emissions. A lumped and distributed parameter model of the entire system is constructed to simulate the performance of the kiln under actual operating conditions. The model is able to predict accurately the temperature distribution along the different modules of the kiln and the operation of the many natural gas burners employed to provide the required thermal power. Furthermore, the temperature of the tiles is also simulated so that the quality of the final product can be addressed by the modelling. Numerical results are validated against experimental measurements carried out on a real ceramic kiln during regular production operations. The developed numerical model demonstrates to be an efficient tool for the investigation of different design solutions for the kiln's components. In addition, a number of control strategies for the system working conditions can be simulated and compared in order to define the best trade off in terms of fuel consumption and product quality. In particular, the paper analyzes the effect of a new burner type characterized by internal heat recovery capability aimed at improving the energy efficiency of the ceramic kiln. The fuel saving and the relating reduction of carbon dioxide emissions resulted in the order of 10% when compared to the standard burner. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Basic survey project for joint implementation. Feasibility study for the diffusion of fluidized bed cement kiln system in China; 1998 nendo kyodo jisshi nado suishin kiso chosa. Chugoku ni okeru ryudosho cement kirun fukyu chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Discussions were given on conversion of shaft kilns mainly used at Tianjin Cement and Huaxin Cement to the fluidized bed cement kiln of the most advanced type. Possibility of energy conservation in China, that is reduction of carbon dioxide emission, was evaluated. This system has been developed by the Center for Coal Utilization, Japan. The system is characterized by reduction of greenhouse effect gas emission, elimination of the problem of dust scattering from sintering facilities, stabilized production of high-quality clinker, capability of using low-grade coal and anthracite, and reduction of cement production cost. As a result of the discussions, the reduction rate of greenhouse effect gases was found about 17 to 33%. The cost effect may be calculated as 2 to 5 thousand yen per ton of CO2 reduction amount assuming the system life of 20 years. If this process has been diffused into China, the quantity of CO2 to be reduced will reach about four million tons annually assuming a diffusion rate of 10%. This project shows as high profitability as about 20% at IRR, and the system is more advantageous economically than the shaft kiln. (NEDO)

  9. Study on the property of the production for Fengdongyan kiln in Early Ming dynasty by INAA and EDXRF

    International Nuclear Information System (INIS)

    Li, L.; Huang, Y.; Sun, H.Y.; Yan, L.T.; Feng, S.L.; Xu, Q.; Feng, X.Q.

    2016-01-01

    A lot of official wares carved “Guan” or the dragon patterns were excavated on the strata of Ming dynasty of the Fengdongyan kiln site at Dayao County. The imperial porcelain was fired in Hongwu and Yongle eras. However, the emergence of this imperial porcelain has triggered academic debate about the property of Fengdongyan kiln in the Early Ming dynasty. Based on the differences of the official kiln management, some scholars have determined that the property of the production for this kiln was the civilian kiln. According to the historical textural records and typology, others preliminary confirmed that Fengdongyan kiln was the official kiln. In this paper, the elemental compositions of body and glaze in imperial and civilian porcelain are study by INAA and EDXRF for determining the property of the production for this kiln in Early Ming dynasty. After the processing of experimental data by geochemical analysis and principal component analysis, the result show that the raw materials for making body and glaze in imperial porcelain are similar with those of the civilian porcelain and the degrees of elutriation for body can be slightly different in HW-M period of Ming dynasty. The analytical results support the view that the Fengdongyan kiln is civilian not official.

  10. Study on the property of the production for Fengdongyan kiln in Early Ming dynasty by INAA and EDXRF

    Energy Technology Data Exchange (ETDEWEB)

    Li, L. [Institute of High Energy Physics, Chinese Academy of Sciences, 19 Yu Quan Lu, Beijing 100049 (China); Huang, Y.; Sun, H.Y. [Institute of High Energy Physics, Chinese Academy of Sciences, 19 Yu Quan Lu, Beijing 100049 (China); University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100049 (China); Yan, L.T.; Feng, S.L.; Xu, Q. [Institute of High Energy Physics, Chinese Academy of Sciences, 19 Yu Quan Lu, Beijing 100049 (China); Feng, X.Q., E-mail: fengxq@ihep.ac.cn [Institute of High Energy Physics, Chinese Academy of Sciences, 19 Yu Quan Lu, Beijing 100049 (China)

    2016-08-15

    A lot of official wares carved “Guan” or the dragon patterns were excavated on the strata of Ming dynasty of the Fengdongyan kiln site at Dayao County. The imperial porcelain was fired in Hongwu and Yongle eras. However, the emergence of this imperial porcelain has triggered academic debate about the property of Fengdongyan kiln in the Early Ming dynasty. Based on the differences of the official kiln management, some scholars have determined that the property of the production for this kiln was the civilian kiln. According to the historical textural records and typology, others preliminary confirmed that Fengdongyan kiln was the official kiln. In this paper, the elemental compositions of body and glaze in imperial and civilian porcelain are study by INAA and EDXRF for determining the property of the production for this kiln in Early Ming dynasty. After the processing of experimental data by geochemical analysis and principal component analysis, the result show that the raw materials for making body and glaze in imperial porcelain are similar with those of the civilian porcelain and the degrees of elutriation for body can be slightly different in HW-M period of Ming dynasty. The analytical results support the view that the Fengdongyan kiln is civilian not official.

  11. Oxy-fuel combustion as an alternative for increasing lime production in rotary kilns

    International Nuclear Information System (INIS)

    Granados, D.A.; Chejne, F.; Mejía, J.M.

    2015-01-01

    Highlights: • A one-dimensional model for oxy-fuel combustion in a rotary kiln was developed. • Flue gas recirculation becomes an important parameter for controlling the process. • Combustion process decreases the flame length making it more dense. • Increases of 12% in raw material with 40% of FGR and conversion of 98% was obtained. - Abstract: The effect of Flue Gas Recirculation (FGR) on the decarbonation process during oxy-fuel combustion in a lime (and cement) rotary kiln is analyzed using an unsteady one-dimensional Eulerian–Lagrangian mathematical model. The model considers gas and limestone as continuous phases and the coal particles as the discrete phase. The model predicts limestone decarbonation, temperature and species distribution of gas and solid phases along the kiln. Simulation results of an air-combustion case are successfully validated with reported experimental data. This model is used to study and to compare the conventional air combustion process with oxy-fuel combustion with FGR ratios between 30% and 80% as controller parameter in this process. Changes in decarbonation process due to energy fluxes by convection and radiation with different FGRs were simulated and analyzed. Simulation results indicate a temperature increase of 20% in the gas and solid phases and a higher decarbonation rate of 40% in relation to the air-combustion case, for a given constant fuel consumption rate. However, for a given temperature, the increase of the CO_2 partial pressure in the oxy-fuel case promotes a reduction of the decarbonation rate. Therefore, there is a compromise between FGR and decarbonation rate, which is analyzed in the present study. Simulation results of the decarbonation step in low FGR cases, compared to air-combustion case, shows that conversion takes place in shorter distances in the kiln, suggesting that the production rate can be increased for existing kilns in oxy-fuel kilns or, equivalently, shorter kilns can be designed for an

  12. Characteristics of Timbers Dried Using Kiln Drying and Radio Frequency-Vacuum Drying Systems

    Directory of Open Access Journals (Sweden)

    Rabidin Zairul Amin

    2017-01-01

    Full Text Available Heavy hardwoods are difficult-to-dry timbers as they are prone to checking and internal stresses when dried using a conventional kiln drying system. These timbers are usually dried naturally to reach 15% to 19% moisture content with an acceptable defects. Besides long drying time, timbers at these moisture contents are not suitable for indoor applications since they will further dry and causing, for example, jointing and lamination failures. Drying to a lower moisture content could only be achieved in artificial drying kilns such as conventional kiln, dehumidification kiln, solar kiln, radio frequency-vacuum, etc. The objective of this study was to evaluate the characteristics of 30 mm and 50 mm thick kekatong (Cynometra spp. timber dried using kiln drying (KD and radio frequency-vacuum drying (RFV system. The investigation involved drying time, moisture content (MC variations between and within boards, drying defects, shrinkage, and drying stress. Drying defects include checks (surface, end, and internal checks and warping (bowing, cuping, spring, and twisting. The results showed that RFV drying time was reduced to 50% compared to the KD. RFV dried boards demonstrated a more uniform MC between and within boards. Shrinkage in width and thickness, as well as tangential/radial and volumetric shrinkages were substantially less in RFV boards. The amount of cupping, bowing and spring were very low and negligible in all drying runs. There was no twisting observed in all drying methods. The number of stress-free RFV board was higher than KD. With proper procedure, the RFV technology could be used for drying heavy hardwoods which are difficult to dry in conventional kilns due to excessive drying times and degradation.

  13. DOE mixed waste metals partition in a rotary kiln wet off-gas system

    International Nuclear Information System (INIS)

    Burns, D.B.; Looper, M.G.

    1994-01-01

    In 1996, the Savannah River Site plans to begin operation of the Consolidated Incineration Facility (CIF) to treat solid and liquid RCRA hazardous and mixed wastes. Test burns were conducted using surrogate CIF wastes spiked with hazardous metals and organics. The partition of metals between the kiln bottom ash, scrubber blowdown solution, and stack gas was measured as a function of kiln temperature, waste chloride content, and waste form (liquid or solid). Three waste simulants were used in these tests, a high and low chloride solid waste mix (paper, plastic, latex, PVC), and a liquid waste mix (benzene and chlorobenzene). An aqueous solution containing: antimony, arsenic, barium, cadmium, chromium, lead, mercury, nickel, silver, and thallium was added to the waste to determine metals fate under various combustion conditions. Test results were used to divide the metals into three general groups, volatile, semi-volatile, and nonvolatile metals. Mercury was the only volatile metal. No mercury remained in the kiln bottom ash under any incineration condition. Lead, cadmium, thallium, and silver exhibited semi-volatile behavior. The partition between the kiln ash, blowdown, and stack gas depended on incineration conditions. Chromium, nickel, barium, antimony, and arsenic exhibited nonvolatile behavior, with greater than 90 wt % of the metal remaining in the kiln bottom ash. Incineration temperature had a significant effect on the partition of volatile and semi-volatile metals, and no effect on nonvolatile metal partition. As incineration temperatures were increased, the fraction of metal leaving the kiln increased. Three metals, lead, cadmium, and mercury showed a relationship between chloride concentration in the waste and metals partition. Increasing the concentration of chlorides in the waste or burning liquid waste versus solid waste resulted in a larger fraction of metal exiting the kiln

  14. Analysis of elemental composition of porcelains unearthed from Waguantan kiln site by PIXE-RBS

    Science.gov (United States)

    Zhou, Z.; Zhang, K.; Xia, C. D.; Liu, M. T.; Zhu, J. J.; An, Z.; Bai, B.

    2015-03-01

    A method combining proton-induced X-ray emission spectrometry (PIXE) and Rutherford backscattering spectrometry (RBS) was used to determine the composition of 61 porcelain shards from the Yuan Dynasty (1271-1368 A.D.) unearthed from the Waguantan kiln site at Tianzhu County in Guizhou Province, China. Based on our previous experimental setup, an electron gun device with a LaB6 crystal cathode was installed to solve the problem created when the incident proton beams generated electric charge accumulations on the surfaces of the insulating porcelain samples, which induced a large bremsstrahlung background. The use of the electron gun has largely eliminated the large bremsstrahlung background and has therefore improved the detection limits for elements, especially for trace elements, and made it possible to determine the origin of the porcelains based on the trace elements. Major and trace elemental compositions of the porcelain bodies and glazes measured by PIXE and RBS were analyzed by the factor analysis method. The factor analysis showed that a few pieces of porcelain with a style similar to the porcelain of the Longquan kiln among the unearthed porcelains from the Waguantan kiln site did not have obvious differences in elemental compositions from other remaining porcelains unearthed from the Waguantan kiln site, indicating that the pieces of unearthed porcelain with the Longquan kiln style did in fact belong to the product fired locally by imitating the model of the Longquan celadon with local raw materials. This result therefore indicated that the Longquan kiln technology that originated from the Five Dynasties (907-960 A.D.) had been propagated to the Waguantan kiln site of Guizhou Province in the Yuan Dynasty.

  15. Analysis of elemental composition of porcelains unearthed from Waguantan kiln site by PIXE–RBS

    International Nuclear Information System (INIS)

    Zhou, Z.; Zhang, K.; Xia, C.D.; Liu, M.T.; Zhu, J.J.; An, Z.; Bai, B.

    2015-01-01

    Highlights: •We analyzed 61 unearthed porcelain shards in Yuan Dynasty by PIXE–RBS. •An electron gun was installed to solve the electric charge accumulations. •The factor analysis was performed for the element compositions. •The “exotic group” porcelain samples unearthed were produced locally. -- Abstract: A method combining proton-induced X-ray emission spectrometry (PIXE) and Rutherford backscattering spectrometry (RBS) was used to determine the composition of 61 porcelain shards from the Yuan Dynasty (1271–1368 A.D.) unearthed from the Waguantan kiln site at Tianzhu County in Guizhou Province, China. Based on our previous experimental setup, an electron gun device with a LaB 6 crystal cathode was installed to solve the problem created when the incident proton beams generated electric charge accumulations on the surfaces of the insulating porcelain samples, which induced a large bremsstrahlung background. The use of the electron gun has largely eliminated the large bremsstrahlung background and has therefore improved the detection limits for elements, especially for trace elements, and made it possible to determine the origin of the porcelains based on the trace elements. Major and trace elemental compositions of the porcelain bodies and glazes measured by PIXE and RBS were analyzed by the factor analysis method. The factor analysis showed that a few pieces of porcelain with a style similar to the porcelain of the Longquan kiln among the unearthed porcelains from the Waguantan kiln site did not have obvious differences in elemental compositions from other remaining porcelains unearthed from the Waguantan kiln site, indicating that the pieces of unearthed porcelain with the Longquan kiln style did in fact belong to the product fired locally by imitating the model of the Longquan celadon with local raw materials. This result therefore indicated that the Longquan kiln technology that originated from the Five Dynasties (907–960 A.D.) had been

  16. Gas phase dispersion in a small rotary kiln

    International Nuclear Information System (INIS)

    Spencer, B.B.

    1981-07-01

    A study was made of nonideal flow of gas in a rotary kiln reactor. A rotating tube 0.165 m in diameter by 2.17 m long, with internal lifting flights, was operated at room temperature. Rotational speeds from 2.0 to 7.0 rpm, air flow rates from 0.351 to 4.178 m 3 /h, and solid contents of 0.0, 5.1, and 15.3% of tube volume were studied. Residence time distribution of the gas was measured by means of the pulse injection technique using a helium tracer. A model was developed based on dispersive flow that exchanges with a deadwater region. Two parameters, a dispersion number describing bulk gas flow and an interchange factor describing exchange between the flow region and the gas trapped in the solids bed, were sufficient to correlate the data, but these parameters are sensitive to experimental error. The model is applicable to analysis of other flow systems, such as packed beds

  17. Study of meterial distribution of Tang tricolor from Huangye kiln

    International Nuclear Information System (INIS)

    Dong Junling; Zhao Weijuan; Liu Guodong; Cheng Huansheng; Liao Yongmin; Zhang Songlin

    2008-01-01

    By using the proton induced X-ray enission (PIXE) method, the measurements of the oxide compound content have veen carried out for the selected 18 samples of Tang tricolor in Huangye kiln. For ascertaining the classification and origin relation of the samples the principal component analysis method was adopted, and the results indicate that the chemical compositions of Tang tricolor body with diggerent glaze colors are close, which shows that their raw material habitat distribution is quite concentrative. But the prescriptions of diffierent color glaze are different. The content of CoO is more than others in blue glaze; CuO is more than others in green glaze; Fe 2 O 3 is more than others in brown and yellow glaze; A1 2 O3 is less than others but SiO 2 is more in white glaze, which shows that glazers material origin is diffierent, but brown and yellow glaze are close and even the same in chemistry component. (authors)

  18. Hydrogen fluoride damage to vegetation from peri-urban brick kilns in Asia: A growing but unrecognised problem?

    International Nuclear Information System (INIS)

    Ahmad, Muhammad Nauman; Berg, Leon J.L. van den; Shah, Hamid Ullah; Masood, Tariq; Büker, Patrick; Emberson, Lisa; Ashmore, Mike

    2012-01-01

    The rapid urbanisation of many cities in south and south-east Asia has increased the demand for bricks, which are typically supplied from brick kilns in peri-urban areas. We report visible foliar damage to mango, apricot and plum trees in the vicinity of traditional Bull’s Trench brick kilns in Peshawar, Pakistan. Visible injury symptoms, hydrogen fluoride concentrations in air, and foliar fluoride concentrations were all greater in the vicinity of brick kilns than at more distant sites, indicating that fluoride emissions from brick kilns were the main cause of damage. Interviews with local farmers established the significant impact of this damage on their livelihoods. Since poorly regulated brick kilns are often found close to important peri-urban agricultural areas, we suggest that this may be a growing but unrecognised environmental problem in regions of Asia where emission control in brick kilns has not been improved. - Highlights: ► Demand for bricks is increasing in many parts of Asia. ► Fluoride emissions from brick kilns may pose a threat to peri-urban agriculture. ► We found extensive injury to fruit orchards close to brick kilns in Peshawar. ► Local farmers suffered large economic losses but did not identify brick kilns as a cause of this. ► The extent of crop damage from brick kilns with poor emission control in the region may not be fully recognised. - Hydrogen fluoride emissions from brick kilns may cause extensive but unrecognised damage to peri-urban crops in Asia.

  19. Development of Portable Venturi Kiln for Agricultural Waste Utilization by Carbonization Process

    Science.gov (United States)

    Agustina, S. E.; Chasanah, N.; Eris, A. P.

    2018-05-01

    Many types of kiln or carbonization equipment have been developed, but most of them were designed for big capacity and some also having low performance. This research aims to develop kiln, especially portable metal kiln, which has higher performance, more environmental- friendly, and can be used for several kinds of biomass or agricultural waste (not exclusive for one kind of biomass) as feeding material. To improve the kiln performance, a venturi drum type of portable kiln has been designed with an optimum capacity of 12.45 kg coconut shells. Basic idea of those design is heat flow improvement causing by venturi effect. The performance test for coconut shell carbonization shows that the carbonization process takes about 60-90 minutes to produce average yields of 23.8%., and the highest temperature of the process was 441 °C. The optimum performance has been achieved in the 4th test, which was producing 24% yield of highest charcoal quality (represented by LHV) in 65 minutes process at average temperature level 485 °C. For pecan shell and palm shell, design modification has been done by adding 6 air inlet holes and 3 ignition column to get better performance. While operation procedure should be modified on loading and air supply, depending on each biomass characteristic. The result of performance test showed that carbonization process of pecan shell produce 17 % yield, and palm shell produce 15% yield. Based on Indonesian Standard (SNI), all charcoal produced in those carbonization has good quality level.

  20. CFD modeling using PDF approach for investigating the flame length in rotary kilns

    Science.gov (United States)

    Elattar, H. F.; Specht, E.; Fouda, A.; Bin-Mahfouz, Abdullah S.

    2016-12-01

    Numerical simulations using computational fluid dynamics (CFD) are performed to investigate the flame length characteristics in rotary kilns using probability density function (PDF) approach. A commercial CFD package (ANSYS-Fluent) is employed for this objective. A 2-D axisymmetric model is applied to study the effect of both operating and geometric parameters of rotary kiln on the characteristics of the flame length. Three types of gaseous fuel are used in the present work; methane (CH4), carbon monoxide (CO) and biogas (50 % CH4 + 50 % CO2). Preliminary comparison study of 2-D modeling outputs of free jet flames with available experimental data is carried out to choose and validate the proper turbulence model for the present numerical simulations. The results showed that the excess air number, diameter of kiln air entrance, radiation modeling consideration and fuel type have remarkable effects on the flame length characteristics. Numerical correlations for the rotary kiln flame length are presented in terms of the studied kiln operating and geometric parameters within acceptable error.

  1. Study on ancient porcelain of Loulinpo Kiln Site by nuclear analysis technology

    International Nuclear Information System (INIS)

    Wang, Y.Q.; Feng, S.L.; Feng, X.Q.; Lei, Y.; Cheng, L.; Xu, Q.; Zhou, Z.X.; Xue, D.X.

    2005-01-01

    Yaozhou Kiln located at Tongchuan of Shanxi Province has lasted continuous history of firing celadon porcelain from Tang Dynasty (618-907A.D.) to Yuan Dynasty (1234-1368A.D.), The firing technology has had important effect for celadon porcelain of many kilns in ancient China. In Jin Dynasty (1127-1234A.D.) and Yuan Dynasty, because of lacking of raw material resources, the central site of Yaozhou Kiln moved from Tongchuan to Lidipo, Shangdian and Chenlu area. Luolinpo site belongs to Yaozhou Kiln series and is one kiln of Shangdian area. The bowl sherds samples of Yuan dynasty stratum excavated in recent year. The glaze color is celadon, black, dark brown and dark reddish brown respectively. Ten pieces of sherds of each glaze color were selected. The main chemical compositions of theses samples were analyzed by XRF and the trace elemental contents were determined by NAA. The result shown that the content of Fe 2 O 3 can decide the kind of glaze color will be. The concentration of CaO, Na 2 O and K 2 O can be used to explain the developing process of firing techniques. Except samples of dark brown glaze, the contents of Fe 2 O 3 and CaO change in small range. The proportions of these main chemical compositions of the porcelain with glaze color of black, celadon and dark reddish brown have little variation. But it was very different form some samples of dark brown glaze.

  2. THE IMPACT OF BRICK KILN OPERATION TO THE DEGRADATION OF TOPSOIL QUALITY OF AGRICULTURAL LAND

    Directory of Open Access Journals (Sweden)

    Md. Sirajul Islam

    2015-10-01

    Full Text Available Brick kiln is a big environmental issue for the agriculture of Bangladesh as it was observed that the agricultural production in the soil close to the brick kiln was lesser than the same soil far from brick kiln. The study was conducted to assess the impact of brick kiln operation to the degradation of topsoil quality at Singair of Kalihati upazila in Tangail, Bangladesh, during the period of July to December 2013. The Soil was collected from areas close to the brick fields and far from the brick fields at a depth of 0-15 cm. The Electrical Conductance (EC was found almost double in the soil samples close to the brick field than the soil samples far from brick field. The organic mattter content in the soil sample close to the brickfield was significantly lower than that of the far soil sample. The mean values of total N, available P and S were also significantly lower in the soil samples close to the brick kiln, 0.05%, 12.4, and 8.36 ppm respectively in the close soils, while 0.06%, 24.6, and 11.7 ppm respectively in the far soil. There were no significant changes observed in the other elements.

  3. COMPARISON BETWEEN WOOD DRYING DEFECT SCORES: SPECIMEN TESTING X ANALYSIS OF KILN-DRIED BOARDS

    Directory of Open Access Journals (Sweden)

    Djeison Cesar Batista

    2015-04-01

    Full Text Available It is important to develop drying technologies for Eucalyptus grandis lumber, which is one of the most planted species of this genus in Brazil and plays an important role as raw material for the wood industry. The general aim of this work was to assess the conventional kiln drying of juvenile wood of three clones of Eucalyptus grandis. The specific aims were to compare the behavior between: i drying defects indicated by tests with wood specimens and conventional kiln-dried boards; and ii physical properties and the drying quality. Five 11-year-old trees of each clone were felled, and only flatsawn boards of the first log were used. Basic density and total shrinkage were determined, and the drying test with wood specimens at 100 °C was carried out. Kiln drying of boards was performed, and initial and final moisture content, moisture gradient in thickness, drying stresses and drying defects were assessed. The defect scoring method was used to verify the behavior between the defects detected by specimen testing and the defects detected in kiln-dried boards. As main results, the drying schedule was too severe for the wood, resulting in a high level of boards with defects. The behavior between the defects in the drying test with specimens and the defects of kiln-dried boards was different, there was no correspondence, according to the defect scoring method.

  4. The Development of the Clay Tobacco Pipe Kiln in the British Isles

    Directory of Open Access Journals (Sweden)

    Allan Peacey

    1996-09-01

    Full Text Available In 1982 Allan Peacey published a study in the form of a synthesis of two chronologically separated kilns used in the production of clay tobacco pipes (Peacey 1982, 3-17. The aims of the present work are: ◦to improve upon this framework ◦to establish how these type of structures fit into the broader picture; to fill the gaps, before, between and after these cameo views ◦to improve understanding of the technology employed and see the roots from which such technology developed. The primary objective is to catalogue all relevant material know to exist in museum and private collections. It is hoped that by this means an understanding of the varied physical characteristics will lead to the establishment of object or function categories around which reports may be structured. Contemporary source documents are also examined to shed further light upon the likely function of the archaeological material. Among the results achieved are the compilation of an extensive catalogue of material associated with tobacco pipe kilns; the establishment of type series for pipe kiln furniture and furniture supplements; a proposed development sequence for pipe kiln muffles; a pattern of consistency in kiln design throughout the study area, and details of the methods used for stem tipping. Readers will be able to view the archaeological evidence as distribution maps, and will be able to explore other aspects of the data through the timeline and site catalogues.

  5. Numerical Study on Heat Transfer to an Arc Absorber Designed for a Waste Heat Recovery System around a Cement Kiln

    DEFF Research Database (Denmark)

    Hosseini, Seyed Mojtaba Mir; Rezaniakolaei, Alireza; Rosendahl, Lasse Aistrup

    2018-01-01

    A numerical study on combined free convection, forced convection, and radiation heat transfers from an industrial isothermal rotating cylinder (cement kiln) is carried out in this work. The investigation is done by the study of two-dimensional (2D) incompressible turbulent flow around the kiln un...

  6. A remote engineering solution for automating a roller hearth kiln

    Directory of Open Access Journals (Sweden)

    João Bosco da Mota Alves

    2008-07-01

    Full Text Available Remote engineering (also known as online engineering may be defined as a combination of control engineering and telematics. In this area, specific activities require computacional skills in order to develop projects where electrical devives are monitored and / or controlled, in an intercative way, through a distributed network (e.g. Intranet or Internet. In our specific case, we will be dealing with an industrial plant. Within the last few years, there has been an increase in the number of activities related to remote engineering, which may be connected to the phenomenon of the large extension experienced by the Internet (e.g. bandwith, number of users, development tools, etc.. This increase opens new and future possibilities to the implementation of advance teleworking (or e-working positions. In this paper we present the architecture for a remote application, accessible through the Internet, able to monitor and control a roller hearth kiln, used in a ceramics industry for firing materials. The proposed architecture is based on a micro web server, whose main function is to monitor and control the firing process, by reading the data from a series of temperature sensors and by controlling a series of electronic valves and servo motors. This solution is also intended to be a low-cost alternative to other potential solutions. The temperature readings are obtained through K-type thermopairs and the gas flow is controlled through electrovalves. As the firing process should not be stopped before its complete end, the system is equipped with a safety device for that specific purpose. For better understanding the system to be automated and its operation we decided to develop a scale model (100:1 and experiment on it the devised solution, based on a Micro Web Server.

  7. [Chemical composition and chromaticity characteristic of Jilan glaze of Ming and Qing official kilns].

    Science.gov (United States)

    Wu, Jun-ming; Zhang, Mao-lin; Li, Qi-jiang; Wu, Juan; Quan, Kui-shan; Cao, Jian-wen

    2012-08-01

    Color glazes of Ming and Qing official kilns are excellent representatives of the famous ancient Chinese porcelains. The study of official ware with Jilan glaze has been an important topic. But it made slow progress due to the rarity of samples with strict production management and using system. The recipes, chemical composition and chromaticity characteristic of the Jilan samples excavated from official kilns in the Ming and Qing dynasties were first discussed by systematical testing with the energy dispersive X-ray fluorescence (EDXRF) and color difference meter. The results showed that the porcelain stone content in Jilan bodies of official kiln in the Ming dynasty is higher than the samples of the Qing dynasty. The manganese content in Jilan glazes of the Ming dynasty is higher than that in the Qing dynasty, while the glaze ash addition and the lightness value in the glaze are opposite.

  8. Analysis of bluish-white porcelain of Fanchang kiln in Anhui province by INAA

    International Nuclear Information System (INIS)

    Yang Yuzhang; Zhang Juzhong

    2008-01-01

    The minor and trace elements in the bluish-white porcelain bodies of Fanchang kiln in different dynasties were determined by instrumental neutron activation analysis (INAA). Multivariable statistical analysis of the experimental data was carried out by SPSS software. The results show that the contents of Yb, Ta, Hf and Th varied notably between early and middle North Song Dynasty. The chemical compositions of Fanchang porcelain bodies can be divided into three groups corresponding to Five Dynasties, early Northern Song and middle Northern Song. Combined with the results of major elements analysis, we think that the raw materials of Fanchang kiln varied in different periods and the using up of fine raw materials was the main reason of Fanchang kiln's decline. (authors)

  9. Sustainability of cement kiln co-processing of wastes in India: a pilot study.

    Science.gov (United States)

    Baidya, Rahul; Ghosh, Sadhan Kumar; Parlikar, Ulhas V

    2017-07-01

    Co-processing in cement kiln achieves effective utilization of the material and energy value present in the wastes, thereby conserving the natural resources by reducing the use of virgin material. In India, a number of multifolded initiatives have been taken that take into account the potential and volume of waste generation. This paper studies the factors which might influence the sustainability of co-processing of waste in cement kilns as a business model, considering the issues and challenges in the supply chain framework in India in view of the four canonical pillars of sustainability. A pilot study on co-processing was carried out in one of the cement plant in India to evaluate the environmental performance, economical performance, operational performance and social performance. The findings will help India and other developing countries to introduce effective supply chain management for co-processing while addressing the issues and challenges during co-processing of different waste streams in the cement kilns.

  10. Dynamic measurement of mercury adsorption and oxidation on activated carbon in simulated cement kiln flue gas

    DEFF Research Database (Denmark)

    Zheng, Yuanjing; Jensen, Anker Degn; Windelin, Christian

    2012-01-01

    of the sulfite converter is short and typically within 2min. Dynamic mercury adsorption and oxidation tests on commercial activated carbons Darco Hg and HOK standard were performed at 150°C using simulated cement kiln gas and a fixed bed reactor system. It is shown that the converter and analyzer system...... are still under development and are investigated in this work. A commercial red brass converter was tested at 180°C and it was found that the red brass chips work in nitrogen atmosphere only, but do not work properly under simulated cement kiln flue gas conditions. Test of the red brass converter using only...... elemental mercury shows that when HCl is present with either SO2 or NOx the mercury measurement after the converter is unstable and lower than the elemental mercury inlet level. The conclusion is that red brass chips cannot fully reduce oxidized mercury to elemental mercury when simulated cement kiln gas...

  11. Thermal decomposition of woody wastes contaminated with radioactive materials using externally-heated horizontal kiln

    International Nuclear Information System (INIS)

    Iwasaki, Toshiyuki; Kato, Shigeru; Yamasaki, Akihiro; Ito, Takuya; Suzuki, Seiichi; Kojima, Toshinori; Kodera, Yoichi; Hatta, Akimichi; Kikuzato, Masahiro

    2015-01-01

    Thermal decomposition experiments of woody wastes contaminated with radioactive materials were conducted using an externally-heated horizontal kiln in the work area for segregation of disaster wastes at Hirono Town, Futaba County, Fukushima Prefecture. Radioactivity was not detected in gaseous products of thermal decomposition at 923 K and 1123 K after passage through a trap filled with activated carbon. The contents of radioactive cesium ( 134 Cs and 137 Cs) were measured in the solid and liquid products of the thermal decomposition experiments and in the residues in the kiln after all of the experiments. Although a trace amount of radioactive cesium was found in the washing trap during the start-up period of operation at 923 K, most of the cesium remained in the char, including the residues in the kiln. These results suggest that most of the radioactive cesium is trapped in char particles and is not emitted in gaseous form. (author)

  12. CFD analysis of a rotary kiln using for plaster production and discussion of the effects of flue gas recirculation application

    Science.gov (United States)

    Gürtürk, Mert; Oztop, Hakan F.; Pambudi, Nugroho Agung

    2018-04-01

    In this study, the CFD analysis of the rotary kiln is carried out for examining effects of various parameters on energy consumption and efficiency of the rotary kiln. The flue gas recirculation using in many applications is a useful method for combusting of fuel unburned in the flue gas. Also, effects of flue gas recirculation on the combusting of fuel, operating temperature and efficiency of the rotary kiln are discussed in this study. The rotary kiln, which is considered in this study, is used in plaster plant. Two different CFD models were created and these models are compared according to many parameters such as temperature distribution, mixture fraction, the mass fraction of O2, CO, CO and CH4 in the combustion chamber. It is found that the plaster plant has a great potential for an increase in energy efficiency. Results obtained for producers of rotary kiln and burner will be useful for determining better design parameters.

  13. Devolatilization and Combustion of Tire Rubber and Pine Wood in a Pilot Scale Rotary Kiln

    DEFF Research Database (Denmark)

    Nielsen, Anders R.; Larsen, Morten B.; Glarborg, Peter

    2012-01-01

    Cement production is highly energy intensive and requires large quantities of fuels. For both economical and environmental reasons, there is an increasing tendency for utilization of alternative fuels in the cement industry, examples being tire derived fuels, waste wood, or different types...... of industrial waste. In this study, devolatilization and combustion of large particles of tire rubber and pine wood with equivalent diameters of 10 mm to 26 mm are investigated in a pilot scale rotary kiln able to simulate the process conditions present in the material inlet end of cement rotary kilns...

  14. SO2 Release as a Consequence of Alternative Fuel Combustion in Cement Rotary Kiln Inlets

    DEFF Research Database (Denmark)

    Cortada Mut, Maria del Mar; Nørskov, Linda Kaare; Glarborg, Peter

    2015-01-01

    The combustion of alternative fuels in direct contact with the bed material of the rotary kiln may cause local reducing conditions and, subsequently, decomposition of sulfates from cement raw materials, increasing the SO2 concentration in the gas phase. The decomposition of sulfates increases...... the sulfur circulation and may be problematic because high sulfur circulation can cause sticky material buildup, affecting the process operation of the cement kiln system. The SO2 release from cement raw materials during combustion of pine wood and tire rubber has been studied experimentally in a high...

  15. COMPARISON BETWEEN WOOD DRYING DEFECT SCORES: SPECIMEN TESTING X ANALYSIS OF KILN-DRIED BOARDS

    OpenAIRE

    Djeison Cesar Batista; Márcio Pereira da Rocha; Ricardo Jorge Klitzke

    2015-01-01

    It is important to develop drying technologies for Eucalyptus grandis lumber, which is one of the most planted species of this genus in Brazil and plays an important role as raw material for the wood industry. The general aim of this work was to assess the conventional kiln drying of juvenile wood of three clones of Eucalyptus grandis. The specific aims were to compare the behavior between: i) drying defects indicated by tests with wood specimens and conventional kiln-dried boards; and ii) ph...

  16. Reducing firing of an early pottery making kiln at Batan Grande, Peru: A Moessbauer study

    International Nuclear Information System (INIS)

    Wagner, U.; Gebhard, R.; Haeusler, W.; Hutzelmann, T.; Riederer, J.; Shimada, I.; Sosa, J.; Wagner, F.E.

    1999-01-01

    Material from field firing experiments using a 2,700-year old Formative kiln at Batan Grande, Peru, was studied by X-ray diffraction and Moessbauer spectroscopy. The experiments explore the technology involved in producing the gray and black reduced ware for which Cupisnique and other Formative ceramics are justly known. During firing, the iron-bearing compounds in clays undergo characteristic changes which depend on kiln temperature and atmosphere. These changes can be observed in the Moessbauer spectra. By comparing spectra of an appropriate clay fired in field experiments and in the laboratory with the spectra of ancient ceramics, a description of Formative firing techniques in a reducing environment is attempted

  17. Fuzzy modeling and control of the calcination process in a kiln

    International Nuclear Information System (INIS)

    Ramirez, M.; Haber, R.

    1999-01-01

    Calcination kilns are strongly nonlinear, multivariable processes, that only can be modeled with great uncertainty. In order to get a quality product and ensure the process efficiency, the controller must keep a prescribed temperature profile optimizing the fuel consumption. In this paper, a design methodology of a multivariable fuzzy controller for a nickel calcination kiln is presented. The controller structure is a classical one, and uses the Mamdani fuzzy inference system. In simulation results the fuzzy controller exhibits a great robustness in presence of several types of disturbances, and a better performance than the PID in same conditions is observed. (author)

  18. The Earliest Chinese Proto-Porcelain Excavated from Kiln Sites: An Elemental Analysis

    OpenAIRE

    Li, Yu; Zhang, Bin; Cheng, Huansheng; Zheng, Jianming

    2015-01-01

    In June 2012, the Piaoshan kiln site was excavated in Huzhou, Zhejiang Province, which hitherto proved to be the earliest known Chinese proto-porcelain kiln. Judging from the decorative patterns of unearthed impressed stoneware and proto-porcelain sherds, the site was determined to date to the late Xia (c. 2070-c. 1600 BC), the first dynasty of China. Here, we report on proton-induced X-ray emission analyses of 118 proto-porcelain and 35 impressed stoneware sherds from Piaoshan and five subse...

  19. Dust collector

    Energy Technology Data Exchange (ETDEWEB)

    Sahourin, H.

    1988-03-22

    This invention relates to a dust collector or filter which may be used for large volume cleaning air for gases or for separating out industrial byproducts such as wood chips, sawdust, and shavings. It relies on filtration or separation using only a uniquely configured medium. A primary, but not exclusive, purpose of the invention is to enable very large throughput, capable of separating or filtering of gases containing up to three or more tons of byproduct with a minimum pressure-drop across the device. No preliminary cycloning, to remove major particulates is necessary. The collector generally comprises a continuous and integral filter medium which is suspended from a plurality of downwardly extending frames forming a series of separate elements having a triangular cross-section, each element being relatively wide at the top and narrow at the bottom to define, between adjacent elements, a divergent collecting space which is wide at the bottom. 11 figs.

  20. Dust Measurements in Tokamaks

    International Nuclear Information System (INIS)

    Rudakov, D; Yu, J; Boedo, J; Hollmann, E; Krasheninnikov, S; Moyer, R; Muller, S; Yu, A; Rosenberg, M; Smirnov, R; West, W; Boivin, R; Bray, B; Brooks, N; Hyatt, A; Wong, C; Fenstermacher, M; Groth, M; Lasnier, C; McLean, A; Stangeby, P; Ratynskaia, S; Roquemore, A; Skinner, C; Solomon, W M

    2008-01-01

    Dust production and accumulation impose safety and operational concerns for ITER. Diagnostics to monitor dust levels in the plasma as well as in-vessel dust inventory are currently being tested in a few tokamaks. Dust accumulation in ITER is likely to occur in hidden areas, e.g. between tiles and under divertor baffles. A novel electrostatic dust detector for monitoring dust in these regions has been developed and tested at PPPL. In DIII-D tokamak dust diagnostics include Mie scattering from Nd:YAG lasers, visible imaging, and spectroscopy. Laser scattering resolves size of particles between 0.16-1.6 (micro)m in diameter; the total dust content in the edge plasmas and trends in the dust production rates within this size range have been established. Individual dust particles are observed by visible imaging using fast-framing cameras, detecting dust particles of a few microns in diameter and larger. Dust velocities and trajectories can be determined in 2D with a single camera or 3D using multiple cameras, but determination of particle size is problematic. In order to calibrate diagnostics and benchmark dust dynamics modeling, pre-characterized carbon dust has been injected into the lower divertor of DIII-D. Injected dust is seen by cameras, and spectroscopic diagnostics observe an increase of carbon atomic, C2 dimer, and thermal continuum emissions from the injected dust. The latter observation can be used in the design of novel dust survey diagnostics

  1. High-resolution dating of ancient ceramic kilns in Thailand, Laos and Burma by radiocarbon and palaeomagnetism

    International Nuclear Information System (INIS)

    Barbetti, M.; Hein, D.

    1997-01-01

    Full text: Radiocarbon dating is widely used on organic samples, especially wood, charcoal and bone. Classical techniques use samples of several grams, but only a few milligrams is needed for measurements by Accelerator Mass Spectrometry (AMS). Palaeomagnetic techniques are readily applicable to the study of ancient kilns. Core samples are drilled from the walls and floors, and oriented before being detached and measured on a sensitive spinner magnetometer in a laboratory. Resolution of a quarter of a century at 95% confidence can be achieved in favourable circumstances but only at certain periods of time. Radiocarbon dating shows that the earliest stoneware ceramics are from the 11th - 12th centuries AD and palaeomagnetism indicates that many in-ground kilns are of this age. Kilns of this type, which were hollowed out in sediments near river banks or old terraces, are found near Sisatchanalai in north-central Thailand and near Luang Prabang in northern Laos; they are similar in age to the Khmer-type kilns found at Suphanburi in central Thailand. A different type of kiln, constructed of bricks and located above-ground, appears towards the end of the 13th century AD. One of the earliest surface kilns at Sisatchanalai has a well determined date of 1290 ± 15 AD (calibrated radiocarbon age, 95% confidence).There is an overlap of the two technologies; stratigraphy and palaeomagnetic results show that in-ground and above-ground brick kilns continue almost side-by-side throughout the 14th century AD. One of the latest in-ground kilns at Sisatchanalai has a date of 1410 ± 25 AD (calibrated radiocarbon age, 95% confidence). There are many brick kilns belonging to the l5th century AD at Sisatchanalai, and they appear then at other sites in north-central Thailand (e.g., Sukhothai and Phitsanulok) and in Burma (e.g., Lagumbyee). In-ground kilns continue to be used in northern Laos even in the 15th century AD. The latest brick kilns at Sisatchanalai are 16th and possibly 17th

  2. Energy efficiency of an innovative vertical axial rotary kiln for pottery production

    Directory of Open Access Journals (Sweden)

    Carlos Andrés Forero Núñez

    2015-01-01

    Full Text Available Colombia is a remarkablecoal producer and exporter worldwide; several sectors use this resource for electricity and thermal energy production. Among them, the ceramic industry consumed 118,590 tons in 2011. Most of the pottery production companies in this country arelocated in rural areas and use old coal fired kilns with low energy efficiencies, generating environmental effects to the population nearby. Despite of the importance of these industries to the small rural economies, the government agencies have closed them due to the lack of development on cleaner devices. This work aims to analyze the thermal behavior of an innovative vertical axial rotary kiln for pottery production, and the energy efficiency varying operation mode. The kiln operated during seven hours needed three hours for stabilizing sintering temperature at 800°C. The mean temperatures of the loading, drying, sintering and cooling stage were 204°C, 223°C, 809°C and 321°C respectively. The convection and radiation heat losses were 15 % whereas the flue gas heat losses 18 %.During continuous operation, the kiln energy efficiency was about 60 %. This design proven to reach the temperatures required in the firing stage of the pottery production; moreover, a gas fuel was fuelled making the process cleaner and more efficient than coal-fired systems.

  3. CFD analysis of a full-scale ceramic kiln module under actual operating conditions

    Science.gov (United States)

    Milani, Massimo; Montorsi, Luca; Stefani, Matteo; Venturelli, Matteo

    2017-11-01

    The paper focuses on the CFD analysis of a full-scale module of an industrial ceramic kiln under actual operating conditions. The multi-dimensional analysis includes the real geometry of a ceramic kiln module employed in the preheating and firing sections and investigates the heat transfer between the tiles and the burners' flame as well as the many components that comprise the module. Particular attention is devoted to the simulation of the convective flow field in the upper and lower chambers and to the effects of radiation on the different materials is addressed. The assessment of the radiation contribution to the tiles temperature is paramount to the improvement of the performance of the kiln in terms of energy efficiency and fuel consumption. The CFD analysis is combined to a lumped and distributed parameter model of the entire kiln in order to simulate the module behaviour at the boundaries under actual operating conditions. Finally, the CFD simulation is employed to address the effects of the module operating conditions on the tiles' temperature distribution in order to improve the temperature uniformity as well as to enhance the energy efficiency of the system and thus to reduce the fuel consumption.

  4. Perspectives and limits for cement kilns as a destination for RDF

    International Nuclear Information System (INIS)

    Genon, G.; Brizio, E.

    2008-01-01

    RDF, the high calorific value fraction of MSW obtained by conventional separation systems, can be employed in technological plants (mainly cement kilns) in order to obtain a useful energy recovery. It is interesting and important to evaluate this possibility within the general framework of waste-to-energy solutions. The solution must be assessed on the basis of different aspects, namely: technological features and clinker characteristics; local atmospheric pollution; the effects of RDF used in cement kilns on the generation of greenhouse gases; the economics of conventional solid fuels substitution and planning perspectives, from the point of view of the destination of RDF and optimal cement kiln policy. The different experiences of this issue throughout Europe are reviewed, and some applications within Italy are also been considered. The main findings of the study are that the use of RDF in cement kilns instead of coal or coke offers environmental benefits in terms of greenhouse gases, while the formation of conventional gaseous pollutants is not a critical aspect. Indeed, the generation of nitrogen oxides can probably be lower because of lower flame temperatures or lower air excess. The presence of chlorinated micro-pollutants is not influenced by the presence of RDF in fuel, whereas depending on the quality of the RDF, some problems could arise compared to the substituted fuel as far as heavy metals are concerned, chiefly the more volatile ones

  5. Perspectives and limits for cement kilns as a destination for RDF.

    Science.gov (United States)

    Genon, G; Brizio, E

    2008-11-01

    RDF, the high calorific value fraction of MSW obtained by conventional separation systems, can be employed in technological plants (mainly cement kilns) in order to obtain a useful energy recovery. It is interesting and important to evaluate this possibility within the general framework of waste-to-energy solutions. The solution must be assessed on the basis of different aspects, namely: technological features and clinker characteristics; local atmospheric pollution; the effects of RDF used in cement kilns on the generation of greenhouse gases; the economics of conventional solid fuels substitution and planning perspectives, from the point of view of the destination of RDF and optimal cement kiln policy. The different experiences of this issue throughout Europe are reviewed, and some applications within Italy are also been considered. The main findings of the study are that the use of RDF in cement kilns instead of coal or coke offers environmental benefits in terms of greenhouse gases, while the formation of conventional gaseous pollutants is not a critical aspect. Indeed, the generation of nitrogen oxides can probably be lower because of lower flame temperatures or lower air excess. The presence of chlorinated micro-pollutants is not influenced by the presence of RDF in fuel, whereas depending on the quality of the RDF, some problems could arise compared to the substituted fuel as far as heavy metals are concerned, chiefly the more volatile ones.

  6. Pulmonary dysfunctions, oxidative stress and DNA damage in brick kiln workers.

    Science.gov (United States)

    Kaushik, R; Khaliq, F; Subramaneyaan, M; Ahmed, R S

    2012-11-01

    Brick kilns in the suburban areas in developing countries pose a big threat to the environment and hence the health of their workers and people residing around them. The present study was planned to assess the lung functions, oxidative stress parameters and DNA damage in brick kiln workers. A total of 31 male subjects working in brick kiln, and 32 age, sex and socioeconomic status matched controls were included in the study. The lung volumes, capacities and flow rates, namely, forced expiratory volume in first second (FEV(1)), forced vital capacity (FVC), FEV(1)/FVC, expiratory reserve volume, inspiratory capacity (IC), maximal expiratory flow when 50% of FVC is remaining to be expired, maximum voluntary ventilation, peak expiratory flow rate and vital capacity were significantly decreased in the brick kiln workers. Increased oxidative stress as evidenced by increased malonedialdehyde levels and reduced glutathione content, glutathione S-transferase activity and ferric reducing ability of plasma were observed in the study group when compared with controls. Our results indicate a significant correlation between oxidative stress parameters and pulmonary dysfunction, which may be due to silica-induced oxidative stress and resulting lung damage.

  7. Palaeointensity determination on an early medieval kiln from Switzerland and the effect of cooling rate

    Science.gov (United States)

    Donadini, F.; Kovacheva, M.; Kostadinova, M.; Hedley, I. G.; Pesonen, L. J.

    The archaeomagnetic intensity reference curve for Western Europe lacks data during the period from 600 to 1000 AD. Baked clay from the walls of a pottery kiln at Reinach (Switzerland), archaeologically dated to the beginning of the 9th century AD, and having a 14C date of 1250 ± 50 BP, was investigated in order to refine the ancient geomagnetic field intensity during this period. A previous study to test the suitability of the material has shown that the magnetic properties of the baked clay from this Reinach kiln are appropriate for an archaeomagnetic study, and furthermore an archaeomagnetic directional date agrees well with the 14C date. A series of palaeointensity measurements was carried out in Sofia (Bulgaria). Here we present the results obtained from the same material, as performed in Helsinki (Finland) using different techniques. The comparison of the results shows significant differences between the two datasets. Based on the literature data, the discrepancy can be explained in terms of the different cooling rates of the samples used during the experiments in the two laboratories. Nevertheless, the results show that the geomagnetic field intensity had a high mean value of 86.85 ± 1.49 μT when the kiln was last used. This observation is consistent with recent studies from France covering the period during which the Reinach kiln functioned.

  8. Provenance and indirect dating study on Hongzhou Kiln porcelains by INAA

    International Nuclear Information System (INIS)

    Feng, X.Q.; Feng, S.L.; Fan, C.S.; Zhang, W.J.; Quan, K.S.

    2005-01-01

    Hongzhou Kiln is one of the six leading celadon kilns in Tang Dynasty and plays an important role in the history of Chinese ceramics for its diverse decoration styles and innovative technology. Archaeologists divided Hongzhou Kiln production into 8 periods, i.e. Eastern Han and Eastern Wu, Western Jin, Eastern Jin, Southern Dynasties, Sui, Early Tang, Middle Tang, Late Tang and Five Dynasties. Up to now, 26 kiln sites have been discovered and excavated. A study on the chemical composition of the porcelains of different periods and provenance will help to know the developing process of Hongzhou celadon such as variation of raw materials, recipes, manufacturing technology, causes of prosperity and decline, etc. Over 200 sherds were collected and their body samples were analyzed by INAA. The compositional differences between samples with the same period but different provenance were observed. The contents of Na, Rb, Ba, Fe, Th, U, etc were found to be different among samples from different periods, which implies they may be used to identify the manufacturing age. The analytical data were further processed by principal component analysis (PCA). The statistical results show that all the sherds can be classified into 5 groups, (1) Eastern Han and Eastern Wu; (2) Western Jin, Eastern Jin and Southern Dynasties; (3) Sui; (4) Early Tang and Middle Tang; (5) Late Tang and Five Dynasties.

  9. Respiratory Abnormalities among Occupationally Exposed, Non-Smoking Brick Kiln Workers from Punjab, India.

    Science.gov (United States)

    Tandon, Supriya; Gupta, Sharat; Singh, Sharanjeet; Kumar, Avnish

    2017-07-01

    Brick manufacturing industry is one of the oldest and fast-growing industries in India that employs a large section of people. Brick kiln workers are occupationally exposed to air pollutants. Nonetheless, only a few studies have so far been conducted on their respiratory health. To investigate the extent of respiratory impairment in brick kiln workers and to correlate it with the duration of exposure. A cross-sectional study was conducted. Spirometric parameters of 110 non-smoking male brick kiln workers aged 18-35 years in Patiala district, Punjab, India, were compared with an age-matched comparison group of 90 unexposed individuals. Brick kiln workers showed a significant (pworkers was associated with the duration of exposure. In workers with >8 years of exposure, the mean values of FEV 1 (1.92 L), FVC (2.01 L), FEF 25-75% (2.19 L/s) and PEFR (4.81 L/s) were significantly (pworkers with workers.

  10. Experimental and theoretical investigation on unburned coal char burnout in a pilot-scale rotary kiln

    Energy Technology Data Exchange (ETDEWEB)

    Federico Cangialosi; Francesco Di Canio; Gianluca Intini; Michele Notarnicola; Lorenzo Liberti; Giulio Belz; Pompilio Caramuscio [Technical University of Bari, Taranto (Italy). Department of Environmental Engineering and Sustainable Development

    2006-11-15

    Oxidation reactivity studies are imperative for improving carbon re-burn technologies and valuing the heat content of unburned carbon within coal combustion ashes. Non-isothermal, thermal gravimetric analysis (TGA) was used to examine the oxidation kinetics of unburned carbon in coal combustion fly ashes having different particle size distributions; TGA results were related to combustion efficiencies as measured in a bench-scale rotary kiln. The activation energy and pre-exponential factor were determined for the chemically-controlled reaction regime; the transition temperatures between chemically-controlled and partially diffusion-controlled combustion regimes were obtained for unburned carbon particles of different sizes. After the oxidation reaction rates were evaluated, the residence time distribution (RTD) of fly ashes in the rotary kiln were experimentally measured and the mean residence times related to process parameters, including the rotating velocity and kiln inclination. By comparing these results with an advective-dispersive model, the axial dispersion coefficient of fly ashes was determined. The reaction rates obtained by thermal analyses and the RTDs were used to predict combustion efficiencies within the kiln and oxidation conditions of unburned carbon using various processing options. 21 refs., 6 figs., 4 tabs.

  11. PIV analysis of merging flow in a simplified model of a rotary kiln

    Energy Technology Data Exchange (ETDEWEB)

    Larsson, I.A.S.; Granstroem, B.R.; Lundstroem, T.S. [Luleaa University of Technology, Division of Fluid and Experimental Mechanics, Luleaa (Sweden); Marjavaara, B.D. [LKAB, Kiruna (Sweden)

    2012-08-15

    Rotary kilns are used in a variety of industrial applications. The focus in this work is on characterizing the non-reacting, isothermal flow field in a rotary kiln used for iron ore pelletization. A downscaled, simplified model of the kiln is experimentally investigated using particle image velocimetry. Five different momentum flux ratios of the two inlet ducts to the kiln are investigated in order to evaluate its effect on the flow field in general and the recirculation zone in particular. Time-averaged and phase-averaged analyses are reported, and it is found that the flow field resembles that of two parallel merging jets, with the same characteristic flow zones. The back plate separating the inlet ducts acts as a bluff body to the flow and creates a region of reversed flow behind it. Due to the semicircular cross-section of the jets, the wake is elongated along the walls. Conclusions are that the flow field shows a dependence on momentum flux ratio of the jets; as the momentum flux ratio approaches unity, there is an increasing presence of von Karman-type coherent structures with a Strouhal number of between 0.16 and 0.18. These large-scale structures enhance the mixing of the jets and also affect the size of the recirculation zone. It is also shown that the inclination of the upper inlet duct leads to a decrease in length of the recirculation zone in certain cases. (orig.)

  12. The Earliest Chinese Proto-Porcelain Excavated from Kiln Sites: An Elemental Analysis.

    Science.gov (United States)

    Li, Yu; Zhang, Bin; Cheng, Huansheng; Zheng, Jianming

    2015-01-01

    In June 2012, the Piaoshan kiln site was excavated in Huzhou, Zhejiang Province, which hitherto proved to be the earliest known Chinese proto-porcelain kiln. Judging from the decorative patterns of unearthed impressed stoneware and proto-porcelain sherds, the site was determined to date to the late Xia (c. 2070-c. 1600 BC), the first dynasty of China. Here, we report on proton-induced X-ray emission analyses of 118 proto-porcelain and 35 impressed stoneware sherds from Piaoshan and five subsequent kiln sites in the vicinity. Using principal components analysis on the major chemical compositions, we reveal the relationships between impressed stoneware and proto-porcelain samples from the six kiln sites. The sherds from different sites have distinctive chemical profiles. The results indicate that the raw materials were procured locally. We find a developmental tendency for early glazes towards mature calcium-based glaze. It is most likely that woody plant ashes with increased calcia-potash ratios were applied to the formula.

  13. The Earliest Chinese Proto-Porcelain Excavated from Kiln Sites: An Elemental Analysis.

    Directory of Open Access Journals (Sweden)

    Yu Li

    Full Text Available In June 2012, the Piaoshan kiln site was excavated in Huzhou, Zhejiang Province, which hitherto proved to be the earliest known Chinese proto-porcelain kiln. Judging from the decorative patterns of unearthed impressed stoneware and proto-porcelain sherds, the site was determined to date to the late Xia (c. 2070-c. 1600 BC, the first dynasty of China. Here, we report on proton-induced X-ray emission analyses of 118 proto-porcelain and 35 impressed stoneware sherds from Piaoshan and five subsequent kiln sites in the vicinity. Using principal components analysis on the major chemical compositions, we reveal the relationships between impressed stoneware and proto-porcelain samples from the six kiln sites. The sherds from different sites have distinctive chemical profiles. The results indicate that the raw materials were procured locally. We find a developmental tendency for early glazes towards mature calcium-based glaze. It is most likely that woody plant ashes with increased calcia-potash ratios were applied to the formula.

  14. Assessment of macro and micro nutrients around brick kilns agricultural environment

    Directory of Open Access Journals (Sweden)

    Abdul Halim Farhad Sikder

    2016-03-01

    Full Text Available Brick kiln is well known as one of the main sources of air pollution; however, the pollutants produced from it do not remain in the air, they ultimately fall down to the soil and pollute the surroundings, therefore, this study was carried out to assess the status of macro (N, P, K and S and micro nutrients (Fe, Mn and Zn, Cu in the agricultural environment near the brick kilns of Young Brahmaputra and Jamuna Floodplain soils. Composite soil and plant samples were collected from four distances such as 250 m, 500 m, 1000 m, and 1500 m in three different sites. Sulphur (2352–3378 mg kg−1, Zn (86–156 mg kg−1 and Cu (24.7–46.9 mg kg−1 are found in the elevated levels near brick kiln soils that is released due to burning of poor quality coal and fire woods. The alarming news is that plant uptake of S and micro nutrients in the nearest areas of the brick kilns are significantly higher than the areas far from the brick production and their concentration ranges from 23 mg kg−1 to 101 mg kg−1 for Zn, 10–41 mg kg−1 for Cu, 35–1309 mg kg−1 for Fe, 26–126 mg kg−1 for Mn and 2590–mg kg−1 for S. Data indicates both soil and plant received maximum amount of micronutrients and S concentrations within 500–1000 m distances from brick kilns. Iron and Mn concentrations vary within a permissible limit but the plant uptake is high. Nitrogen concentrations is increasing with the distance from the brick kilns in both soils and plants but no definite pattern of P and K accumulation was found. Research suggested avoiding agricultural practice nearby brick kiln soils due to micronutrient contamination in order to preserve adjoined agricultural environment.

  15. Analysis of elemental composition of porcelains unearthed from Waguantan kiln site by PIXE–RBS

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Z. [Key Laboratory of Radiation Physics and Technology of Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064 (China); Zhang, K. [School of History and Culture, Sichuan University, Chengdu 610064 (China); Xia, C.D.; Liu, M.T.; Zhu, J.J. [Key Laboratory of Radiation Physics and Technology of Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064 (China); An, Z., E-mail: anzhu@scu.edu.cn [Key Laboratory of Radiation Physics and Technology of Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064 (China); Bai, B., E-mail: baibin@scu.edu.cn [School of History and Culture, Sichuan University, Chengdu 610064 (China)

    2015-03-01

    Highlights: •We analyzed 61 unearthed porcelain shards in Yuan Dynasty by PIXE–RBS. •An electron gun was installed to solve the electric charge accumulations. •The factor analysis was performed for the element compositions. •The “exotic group” porcelain samples unearthed were produced locally. -- Abstract: A method combining proton-induced X-ray emission spectrometry (PIXE) and Rutherford backscattering spectrometry (RBS) was used to determine the composition of 61 porcelain shards from the Yuan Dynasty (1271–1368 A.D.) unearthed from the Waguantan kiln site at Tianzhu County in Guizhou Province, China. Based on our previous experimental setup, an electron gun device with a LaB{sub 6} crystal cathode was installed to solve the problem created when the incident proton beams generated electric charge accumulations on the surfaces of the insulating porcelain samples, which induced a large bremsstrahlung background. The use of the electron gun has largely eliminated the large bremsstrahlung background and has therefore improved the detection limits for elements, especially for trace elements, and made it possible to determine the origin of the porcelains based on the trace elements. Major and trace elemental compositions of the porcelain bodies and glazes measured by PIXE and RBS were analyzed by the factor analysis method. The factor analysis showed that a few pieces of porcelain with a style similar to the porcelain of the Longquan kiln among the unearthed porcelains from the Waguantan kiln site did not have obvious differences in elemental compositions from other remaining porcelains unearthed from the Waguantan kiln site, indicating that the pieces of unearthed porcelain with the Longquan kiln style did in fact belong to the product fired locally by imitating the model of the Longquan celadon with local raw materials. This result therefore indicated that the Longquan kiln technology that originated from the Five Dynasties (907–960 A.D.) had been

  16. Study of provenance properties on ancient porcelain of Yue Kiln at Si-long-kou with NAA

    International Nuclear Information System (INIS)

    Feng Songlin; Fan Dongyu; Feng Xiangqian; Cheng Lin; Lei Yong; Xu Qing; Quan Huishan; Shen Yueming; Zhou Zhexi; Zhang Wenjiang

    2005-01-01

    Chinese ancient porcelain history has lasted about three thousands years from Shang Dynasty (1100∼1600 BC). A large amount of ancient porcelain sherds with accuracy provenance and ages were excavated from a lot of kiln sites in China. Archaeologists and ceramic experts have recognized and researched it with excavated stratum, utensil shape, body quality, glaze color and painting pattern. However, the appearance characteristic of some ancient porcelain manufactured in different kilns is similar. Therefore, it is still difficult to identify the provenance and ages of the samples excavated from some sites using traditional methods. Up, to now, many problems of Chinese ancient porcelain are confused for archaeologist and collecting experts. The elemental composition of ancient porcelain shows certain information of provenance and age. Especially, the sorts and contents of the elements in porcelain didn't change, so it is very useful to determine the provenance of ancient porcelain with elemental composition characteristics. Provenance characteristic is the important scientific information to identify ancient porcelain wares excavated from sites and graves. The porcelain samples of Si-Long-Kou Yue kiln in Zhejiang Province of china have been analyzed with NAA in this paper. The provenance characteristic was compared with it of Hong-Zhou kiln of Jiang-Xi Province and Yao-Zhou kiln of Shan-Xi Province. The experimental data were studied with statistic methods. The results show that the chemical compositions of porcelain body samples for three kilns were different. The difference was been able identified. The porcelain body materials of both Si-Long-Kou Yue kiln and Hong-Zhou kiln of Jiang-Xi were similar. The samples of Yao-Zhou kiln in north of China existed obvious difference.

  17. Modeling of Installations with a Rotary Kiln for Thermal Decontamination of Wastes

    Directory of Open Access Journals (Sweden)

    Krot O.P.

    2018-04-01

    Full Text Available The object of the study is a plant for incineration of solid wastes in a rotary kiln with an afterburning chamber and thermal catalytic emission purification. The aim of the study was to determine the rational layout of the solid wastes loading system and the location of the burner during combustion in the system - a rotary kiln and an afterburning chamber. The results of simulation countercurrent and concurrent gas flow and wastes in the form of temperature gradients in the rotary kiln and afterburner chamber are presented. It is found that in the initial part of the rotary kiln, a temperature of more than 1000 °C is created on its lower surface, almost one-third of the length of the furnace (2.5-3 times more than in the concurrent mode. In a zone close to unloading, the temperature is minimal (less than 100 °C, therefore, the slag does not tolerate heat from the furnace, it has time to cool down. Criteria for the efficiency of the rotary kiln have been proposed: the length of the section where the maximum combustion temperature is reached, the length of the section before discharge of the slag, the temperature of the slag. A more efficient configuration for all the criteria is one that ensures the counter movement of debris and gas. To effectively use the volume of the afterburner chamber, the burners must be located at the maximum distance from each other. The outlet flue must also be as far from the burners as possible.

  18. Mini-cusab kiln for rapid small-scale manufacture of charcoal from scrub, coconut wood and coconut shells

    Energy Technology Data Exchange (ETDEWEB)

    Little, E C.S.

    1978-05-01

    Following the development and operation of the mini-cusab kiln in New Zealand, FAO tested it successfully in the South Pacific where there is a glut of coconut wood, which has a very high moisture content. It is based on a 44 gallon drum and its construction and subsequent operation are described. It is designed to be supplied continuously with fuel until full of charcoal. The kilns have air ducts which are sealed with plugs as the level of charcoal formed by the continuous fueling rises within the kiln.

  19. Rotary kiln incinerator engineering tests on simulated transuranic wastes from the Idaho National Engineering Laboratory. Final report

    International Nuclear Information System (INIS)

    Pattengill, M.G.; Brunner, F.A.; Fasso, J.L.; Mitchel, S.R.; Praskac, R.T.

    1982-09-01

    Nine rotary kiln incineration tests were performed at Colorado School of Mines Research Institute on simulated transuranic waste materials. The rotary kiln incinerator used as 3 ft ID and 30 ft long and was included in an incineration system that also included an afterburner and a baghouse. The purpose of the incineration test program was to determine the applicability and operating characteristics of the rotary kiln with relation to the complete incineration of the simulated waste materials. The results of the study showed that the rotary kiln did completely incinerate the waste materials. Off-gas determinations showed emission levels of SO 2 , NO/sub x/, H 2 SO 4 , HC1, particulate loading, and hydrocarbons, as well as exhaust gas volume, to be within reasonable controllable ranges in a production operation. Included in the report are the results of materials and energy balances, based upon data collected, and design recommendations based upon the data and upon observations during the incineration operation

  20. Comparison of two kiln-drying schedules for turkish hazel ( Corylus colurna ) lumber of 5-cm thickness

    OpenAIRE

    Korkut, Süleyman; As, Nusret; Büyüksari, Ümit

    2018-01-01

    Abstract: Turkish hazel (Corylus colurna) lumber with a nominal thickness of 5 cm from the Kastamonu region, Turkey, was dried through conventional kiln drying using two different programs, a non-protective drying schedule and a protective drying schedule. The goal of the study was to obtain a kiln schedule that would maintain wood quality and also save drying time until a final moisture content of 8 ± 2% was reached. The intensity of warping (twisting, bowing, cupping, crooking), superficial...

  1. Determination of heavy metals in agricultural soil adjacent to functional brick kilns: a case study of rawalpindi

    International Nuclear Information System (INIS)

    Achakzai, K.; Khalid, S.; Bibi, A.

    2017-01-01

    Brick making is one of the growing industry of Pakistan which had great contribution in the development of country. In order to meet the demands of urbanization the industry's production rate is also increasing. This has lead to the combustion of enormous amount of coal and other materials thus deteriorating the quality of environment. Brick kilns in developing countries are considered as one of the important source of pollution. Heavy metals are one of the reported pollutants from brick kilns and are highly persistent, non-biodegradable in nature and are serious threat to the environment. The aim of the current study was to assess the level of heavy metals in the soil and vegetation around three selected brick kilns sites in Rawalpindi. The study was conducted from October 2013 to May 2014. The concentration of heavy metals in the soil and plants were determined with standard protocols. The investigated concentration of heavy metals in plants and soils were compared with the WHO standards. It was found that the concentrations of all studied metals were above the permissible limits especially at agriculture soil located adjacent to brick kilns. However, at few sites the concentrations were found below the permissible limits. The results of study showed that brick kilns have great potential of deteriorating the quality of environment so, it is recommended that the monitoring of soil and plants around brick kilns should be carried out on regular basis in order to develop control measures to prevent the impacts of heavy metals pollution. (author)

  2. A feasibility study to determine the functionality of a novel rocking kiln - fluidized bed reactor for the treatment of waste

    International Nuclear Information System (INIS)

    Mohamad Azman Che Mat Isa; Muhd Noor Muhd Yunus; Mohamad Puad Abu; Shahazrin Mohd Nasir; Mohd fairus Abdul Farid

    2004-01-01

    Rotary kiln has been widely used in incineration and studied by many researches. Solid wastes of various shapes, sizes and heat value can be fed into rotary kiln either in batches or continually. Waste combustion in rotary kiln involves rotation method and the residence time depends on the length and diameter of the rotary kiln and the total stoichiometric air given to the system. Rocking system is another technology used in incinerator. In the rocking system, internal elements in the combustion chamber move to transports and mix the burning waste so that all combustible material in the waste is fully burnt. Another technology in incinerator is the fluidized bed This method uses air to fluidized the sand thus enhancing the combustion process. The total air is controlled in order to obtain a suitable fluidized condition This preliminary study was conducted to study the feasibility of an incinerator system when three components viz. the rotary kiln, rocking system and fluidized bed are combined This research was also conducted to obtain preliminary data parameters of the three components such as the suitable temperature, the angle of the kiln, residence time, total air for fluidization, rocking speed and the devolatilization rate. The samples used in this research were the palm oil kernel shells. The results of the studies showed that the palm oil kernel shells combusted evenly using the new parameters. (Author)

  3. LADEE LUNAR DUST EXPERIMENT

    Data.gov (United States)

    National Aeronautics and Space Administration — This archive bundle includes data taken by the Lunar Dust Experiment (LDEX) instrument aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft....

  4. Construction dust amelioration techniques.

    Science.gov (United States)

    2012-04-01

    Dust produced on seasonal road construction sites in Alaska is both a traffic safety and environmental concern. Dust emanating from : unpaved road surfaces during construction severely reduces visibility and impacts stopping sight distance, and contr...

  5. On Dust Charging Equation

    OpenAIRE

    Tsintsadze, Nodar L.; Tsintsadze, Levan N.

    2008-01-01

    A general derivation of the charging equation of a dust grain is presented, and indicated where and when it can be used. A problem of linear fluctuations of charges on the surface of the dust grain is discussed.

  6. Physics of interstellar dust

    CERN Document Server

    Krugel, Endrik

    2002-01-01

    The dielectric permeability; How to evaluate grain cross sections; Very small and very big particles; Case studies of Mie calculus; Particle statistics; The radiative transition probability; Structure and composition of dust; Dust radiation; Dust and its environment; Polarization; Grain alignment; PAHs and spectral features of dust; Radiative transport; Diffuse matter in the Milky Way; Stars and their formation; Emission from young stars. Appendices Mathematical formulae; List of symbols.

  7. Dust as a surfactant

    International Nuclear Information System (INIS)

    Ignatov, A M; Schram, P P J M; Trigger, S A

    2003-01-01

    We argue that dust immersed in a plasma sheath acts as a surfactant. By considering the momentum balance in a plasma sheath, we evaluate the dependence of the plasma surface pressure on the dust density. It is shown that the dust may reduce the surface pressure, giving rise to a sufficiently strong tangential force. The latter is capable of confining the dust layer inside the sheath in the direction perpendicular to the ion flow

  8. Study on the pelletizing of sulfate residue with magnetite concentrate in grate-kiln system

    Directory of Open Access Journals (Sweden)

    Shufeng Y.

    2010-01-01

    Full Text Available The experiment on the feasibility of pelletizing with magnetite concentrate and the wasted sulfate residue was carried out, to research the performance of pellet in grate-kiln system and simulate the grate-kiln pelletizing process in the micro-pellet roasting simulation system in laboratory, and the process experiments on preheating and roasting sections were conducted. The results show that in order to obtain pellet with good performance and the magnetite concentrate should be over 20 in mass percent, the suitable pelletizing time is about 10 min and moisture is around 12.5%. Also, according to the process parameters of drying and preheating sections obtained from experiment, it will be successful to use magnetite concentrate and the wasted sulfate residue for pelletizing, which exploits a new way for the use of sulfate residue.

  9. Emissions of air toxics from a simulated charcoal kiln. Final report, October 1997--September 1998

    International Nuclear Information System (INIS)

    Lemieux, P.M.

    1999-06-01

    The report gives results of experiments in a laboratory-scale charcoal kiln simulator to evaluate emissions of hazardous air pollutants from the production of charcoal in Missouri-type kilns. Fixed combustion gases were measured using continuous monitors. In addition, other pollutants, including methanol, volatile organic compounds, semivolatile organic compounds, and particle emission rates and size distributions were measured using various techniques. Emissions of all pollutants are reported in units of grams emitted per unit mass of initial wood converted to charcoal. Two burn conditions--slow and fast--were examined. High levels of methanol, benzene, and fine particulate were emitted in all tests. The estimated emissions from the fast burn conditions were significantly higher than those from the slow burn conditions

  10. Improvement of energy efficiency in glass-melting furnaces, cement kilns and baking ovens

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, M.D.G. [Technical University of Lisbon (Portugal). Instituto Superior Tecnico; Nogueira, M. [IrRADIARE, R and D in Engineering andrsholm Environment, Oeiras (Portugal)

    1997-08-01

    This paper is aimed at presenting the utilisation of dedicated modelling tools for the optimisation of a variety of thermal equipment for high-, medium-, and low-temperature heat transfer process. A combination of modelling with advanced extensive on-line measurements is proposed as an approach for the development of optimisation procedures able to be used in equipment design and operation. The industrially oriented utilisation of modelling is discussed considering the state-of-the-art and the application of existing codes capable of computing the three-dimensional characteristics of the aerodynamics, mixing, combustion (single- or multi-phase), pollutants formation and heat transfer of industrial combustion equipment. The present paper describes modelling tools for the optimisation of a glass-melting furnace, a ceramic kiln, a cement kiln and a baking oven. Significant reduction of energy consumption and low-cost abatement were achieved for these four industrial situations. (author)

  11. Selenium recovery from kiln powder of cement manufacturing by chemical leaching and bioreduction.

    Science.gov (United States)

    Soda, S; Hasegawa, A; Kuroda, M; Hanada, A; Yamashita, M; Ike, M

    2015-01-01

    A novel process by using chemical leaching followed by bacterial reductive precipitation was proposed for selenium recovery from kiln powder as a byproduct of cement manufacturing. The kiln powder at a slurry concentration of 10 w/v% with 0.25 M Na2CO3 at 28°C produced wastewater containing about 30 mg-Se/L selenium. The wastewater was diluted four-fold and adjusted to pH 8.0 as preconditioning for bioreduction. A bacterial strain Pseudomonas stutzeri NT-I, capable of reducing selenate and selenite into insoluble elemental selenium, could recover about 90% selenium from the preconditioned wastewater containing selenium of 5 mg-Se/L when supplemented with lactate or glycerol. The selenium concentrations in the treated wastewater were low around the regulated effluent concentration of 0.1 mg-Se/L in Japan.

  12. Energy consumption analysis and simulation of waste heat recovery technology of ceramic rotary kiln

    Science.gov (United States)

    Chen, Zhiguang; Zhou, Yu; Qin, Chaokui; Zhang, Xuemei

    2018-03-01

    Ceramsite is widely used in the construction industry, insulation works and oil industry in China, and the manufacture equipment is mainly industrial kiln. In this paper, energy consumption analysis had been carried out through experimental test of a Ceramsite kiln in Henan province. Results showed that the discharge temperature of Ceramsite was about 1393K, and the waste heat accounted for 22.1% of the total energy consumption. A structure of cyclone preheater which recovered waste heat of the high temperature Ceramsite by blast cooling was designed. Then, using Fluent software, performance of the unit was simulated. The minimum temperature that Ceramsite could reach, heat dissipating capacity of Ceramsite, temperature at air outlet, wall temperature of the unit and pressure loss were analyzed. Performance of the designed unit under different inlet velocity was analyzed as well.

  13. Mixing large and small particles in a pilot scale rotary kiln

    DEFF Research Database (Denmark)

    Nielsen, Anders Rooma; Aniol, Rasmus Wochnik; Larsen, Morten Boberg

    2011-01-01

    The mixing of solid alternative fuel particles in cement raw materials was studied experimentally by visual observation in a pilot scale rotary kiln. Fuel particles were placed on top of the raw material bed prior to the experiment. The percentage of particles visible above the bed as a function...... of time was evaluated with the bed predominantly in the rolling bed mode. Experiments were conducted to investigate the effects of fuel particle size and shape, fuel particle density, rotary kiln fill degree and rotational speed. Large fuel particles and low-density fuel particles appeared more on top...... of the bed than smaller particles and high-density fuel particles. Fuel particle dimensions and sphericity were important parameters for the percentage of visible particles. Increasing bed fill degree and/or increasing rotational speed decreased the percentage of particles visible on top of the bed...

  14. Parametrication of numerical simulation of drying process in atypicall condenzation lumber kiln

    Directory of Open Access Journals (Sweden)

    Jiří Zejda

    2004-01-01

    Full Text Available This work deal with modelling of the process of drying, air flow, temperature and moisture distribution in a condensation lumber kiln. This model was made and solved in the computing system ANSYS with the use of the finite element method. There are comparationes of the 2D and 3D models, shape of wood stacks and variability of their parameters (height, width, length, cross section in the work. The flow velocity and orientation, pressure and temperature field were observed.

  15. Prediction of the granulometric and morphological evolution of a powder in a continuous conversion kiln

    International Nuclear Information System (INIS)

    Patisson, F.; Hebrard, S.; Ablitzer, D.; Ablitzer-Thouroude, C.; Hebrard, S.

    2006-01-01

    The UO 2 powder used for the preparation of nuclear fuel pellets is obtained in France by a dry way conversion of gaseous UF 6 . The process includes two steps: hydrolysis into UO 2 F 2 , then reducing pyro-hydrolysis into UO 2 in a continuous conversion kiln. The physical characteristics (morphology, grain size distribution) of the obtained UO 2 powder condition its use properties (sintering ability, casting ability and mechanical strength). A model describing the morphological evolution of the powder in the continuous conversion kiln has been developed in order to dispose of a prediction tool for the morphological characteristics of the UO 2 powder according to its formation conditions. The first part of this work has consisted to model the transport of the powder in the kiln, describing particularly the exchanges between the dense phase (powder bed) and the dispersed phase (rain of particles suspension). One of the originality of the developed model is the taking into account of the role of the raising devices for the calculus of the dynamical variables. The second part has consisted to identify, describe and couple to the preceding dynamical model the phenomena responsible of the morphological and granulometric evolution of the powder in the continuous conversion kiln. A population of fractal agglomerates is considered whose number and size evolve by brownian agglomeration, differential sedimentation agglomeration, pre sintering, fragmentation, and chemical transformations by ex-nucleation and growth. This model uses the formalism of the population balances and the grain size distribution is discretized into sections. The results of the dynamical and morphological calculations are compared to the available measurements. At last is analyzed the respective influence of the different morphological evolution mechanisms on the ended grain size distribution. (O.M.)

  16. Characteristics of Timbers Dried Using Kiln Drying and Radio Frequency-Vacuum Drying Systems

    OpenAIRE

    Rabidin Zairul Amin; Seng Gan Kee; Wahab Mohd Jamil Abdul

    2017-01-01

    Heavy hardwoods are difficult-to-dry timbers as they are prone to checking and internal stresses when dried using a conventional kiln drying system. These timbers are usually dried naturally to reach 15% to 19% moisture content with an acceptable defects. Besides long drying time, timbers at these moisture contents are not suitable for indoor applications since they will further dry and causing, for example, jointing and lamination failures. Drying to a lower moisture content could only be ac...

  17. A Numerical Assessment of the Air Flow Behaviour in a Conventional Compact Dry Kiln

    OpenAIRE

    Paulo Zdanski; Daniel Possamai; Miguel Vaz Jr.

    2015-01-01

    Convective drying is the most common drying strategy used in timber manufacturing industries in the developing world. In convective drying, the reduction rate of the moisture content is directly affected by the flow topology in the inlet and exit plenums and the air flow velocity in the channels formed by timber layers.Turbulence, boundary layer separation, vortex formation and recirculation regions are flow features that are intrinsically associated with the kiln geometry, which in turn dict...

  18. Continuous pyrolysis of biomass feedstocks in rotary kiln convertors. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Henry, Jr, H. H.; Kimzey, J. R.; Turpin, J. L.; MacCallum, R. N.

    1979-08-30

    The biomass research program at the University of Arkansas has developed three experimental projects or tasks for the attainment of its objectives. They are: (1) utilization of the existing full scale convertor for testing and data acquisition at Jonesboro, Arkansas; (2) development of a scale model rotary pyrolytic convertor (bench scale research kiln); and (3) development of analytical laboratory services for the analysis of feedstocks and products, and for basic pyrolytic process studies. The project at Jonesboro, Arkansas, which aimed at testing the Angelo convertor concept through heat and material balances over the available range of operations, could not completely achieve this objective because of the severe mechanical and structural deficiencies in the full scale convertor. A limited number of data have been taken in spite of the deficiencies of the machine. The scale model rotary kiln has been the most successful of the three projects. The kiln has been completed as planned and successfully operated with a number of feedstock materials. Good qualitative data have been obtained on conversion rate capacities, charcoal yields, and off gas combustion product temperatures. In all, about one hundred test runs were made in the scale model kiln. About 90% of the results expected were attained. The laboratory services project was designed to provide analytical testing for the other two projects and to do basic studies in biomass material conversion processes. The project delivered the testing services, but was severely restricted in the area of basic studies because of the failure of the main instrument, the gas chromatograph, to operate successfully. In all it is estimated that this project attained about 80% of its expected goals.

  19. Development of Hybrid Kiln Drying System with Radio Frequency Heating for the Sugi Heart Timber

    OpenAIRE

    Piao, Jinji; Fujimoto, Noboru; Yamamoto, Yasushi; Nagata, Soji

    2007-01-01

    In this study, proper applied stage of the radio-frequency (RF) heating during kiln drying based on the quality concerning the surface checks of the boxed heart timbers was examined. At the stage of the RF heating the moisture contents decreased clearly at the internal parts of timbers. The surface stress of the sugi (Cryptomeria japonica D. Don) boxed heart timber changed into the compression stress by the RF heating in any drying stage. The surface checks increased according to the decrease...

  20. Production Of Bio fuel Starter From Biomass Waste Using Rocking Kiln Fluidized Bed System

    International Nuclear Information System (INIS)

    Mohamad Azman Che Mat Isa; Muhd Noor Muhd Yunus; Zulkafli Ghazali; Mohd Zaid Mohamed; Phongsakorn, P.T.; Mohamad Puad Abu

    2014-01-01

    The biggest biomass source in Malaysia comes from oil palm industry. According to the statistic in 2010, Malaysia produced 40 million tones per year of biomass of which 30 million tones of biomass originated from the oil palm industries. The biomass waste such as palm kernel shell can be used to produce activated carbon and bio fuel starter. A new type of rotary kiln, called Rocking Kiln Fluidized Bed (RKFB) was developed in Nuclear Malaysia to utilize the large amount of the biomass to produce high value added products. This system is capable to process biomass with complete combustion to produce bio fuel starter. With this system, the produced charcoal has calorific value, 33MJ/ kg that is better than bituminous coal with calorific value, 25-30 MJ/ kg. In this research, the charcoals produced were further used to produce the bio fuel starter. This paper will elaborate the experimental set-up of the Rocking Kiln Fluidized Bed (RKFB) for bio fuel starter production and the quality of the produced bio fuel starter. (author)

  1. Feasibility of disposing waste glyphosate neutralization liquor with cement rotary kiln

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Y.; Bao, Y.B.; Cai, X.L.; Chen, C.H. [College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009 (China); State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009 (China); Ye, X.C., E-mail: yexuchu@njtech.edu.cn [College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009 (China); State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 210009 (China)

    2014-08-15

    Highlights: • The waste neutralization liquor was injected directly into the kiln system. • No obvious effect on the quality of cement clinker. • The disposing method was a zero-discharge process. • The waste liquor can be used as an alternative fuel to reduce the coal consumption. - Abstract: The waste neutralization liquor generated during the glyphosate production using glycine-dimethylphosphit process is a severe pollution problem due to its high salinity and organic components. The cement rotary kiln was proposed as a zero discharge strategy of disposal. In this work, the waste liquor was calcinated and the mineralogical phases of residue were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The mineralogical phases and the strength of cement clinker were characterized to evaluate the influence to the products. The burnability of cement raw meal added with waste liquor and the calorific value of waste liquor were tested to evaluate the influence to the thermal state of the kiln system. The results showed that after the addition of this liquor, the differences of the main phases and the strength of cement clinker were negligible, the burnability of raw meal was improved; and the calorific value of this liquor was 6140 J/g, which made it could be considered as an alternative fuel during the actual production.

  2. Feasibility of disposing waste glyphosate neutralization liquor with cement rotary kiln

    International Nuclear Information System (INIS)

    Bai, Y.; Bao, Y.B.; Cai, X.L.; Chen, C.H.; Ye, X.C.

    2014-01-01

    Highlights: • The waste neutralization liquor was injected directly into the kiln system. • No obvious effect on the quality of cement clinker. • The disposing method was a zero-discharge process. • The waste liquor can be used as an alternative fuel to reduce the coal consumption. - Abstract: The waste neutralization liquor generated during the glyphosate production using glycine-dimethylphosphit process is a severe pollution problem due to its high salinity and organic components. The cement rotary kiln was proposed as a zero discharge strategy of disposal. In this work, the waste liquor was calcinated and the mineralogical phases of residue were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD). The mineralogical phases and the strength of cement clinker were characterized to evaluate the influence to the products. The burnability of cement raw meal added with waste liquor and the calorific value of waste liquor were tested to evaluate the influence to the thermal state of the kiln system. The results showed that after the addition of this liquor, the differences of the main phases and the strength of cement clinker were negligible, the burnability of raw meal was improved; and the calorific value of this liquor was 6140 J/g, which made it could be considered as an alternative fuel during the actual production

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

    International Nuclear Information System (INIS)

    Ferreira, Luis Leonardo Horne Curimbaba

    2006-01-01

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

  4. Improvements in Pyrolysis of Wastes in an Externally Heated Rotary Kiln

    Science.gov (United States)

    Suzuki, Tomoko; Okazaki, Teruyuki; Yamamoto, Kenji; Nakata, Hiroyuki; Fujita, Osamu

    The effects of rotating speed and internal structure on the performance of an externally heated rotary kiln for waste pyrolysis were investigated. A newly developed method was adopted to evaluate the overall heat transfer coefficient km-w from the inner wall to the wastes for this purpose. The experimental results revealed that km-w monotonically increased with the number of lifters and their height. When six lifters 200 mm in height were attached to the inner wall of the kiln, the mean value of km-w increased from 38.6 W/m2K to 45.3 W/m2K at 2.7 rpm. In addition, km-w increased to 50.1 W/m2K when the rotating speed was increased to 4.0 rpm. In the water vaporization phase during the course of the pyrolysis process, the height of the lifters had a significant influence on km-w. However, the number of lifters had a significant impact on km-w in the pyrolysis phase of the plastic-based wastes. According to measurements, a 10 % increase in km-w could be obtained when installing lifters to attain a ratio of lifter height Hl to the thickness of the waste layer Hw larger than 0.45 or when arc length between two lifters Ll to the arc length of the interface between the wastes and the kiln wall Lw was larger than 1.

  5. Thermal co-treatment of combustible hazardous waste and waste incineration fly ash in a rotary kiln.

    Science.gov (United States)

    Huber, Florian; Blasenbauer, Dominik; Mallow, Ole; Lederer, Jakob; Winter, Franz; Fellner, Johann

    2016-12-01

    As current disposal practices for municipal solid waste incineration (MSWI) fly ash are either associated with significant costs or negative environmental impacts, an alternative treatment was investigated in a field scale experiment. Thereto, two rotary kilns were fed with hazardous waste, and moistened MSWI fly ash (water content of 23%) was added to the fuel of one kiln with a ratio of 169kg/Mg hazardous waste for 54h and 300kg/Mg hazardous waste for 48h while the other kiln was used as a reference. It was shown that the vast majority (>90%) of the inserted MSWI fly ash was transferred to the bottom ash of the rotary kiln. This bottom ash complied with the legal limits for non-hazardous waste landfills, thereby demonstrating the potential of the investigated method to transfer hazardous waste (MSWI fly ash) into non-hazardous waste (bottom ash). The results of a simple mixing test (MSWI fly ash and rotary kiln bottom ash have been mixed accordingly without thermal treatment) revealed that the observed transformation of hazardous MSWI fly ash into non-hazardous bottom ash during thermal co-treatment cannot be referred to dilution, as the mixture did not comply with legal limits for non-hazardous waste landfills. For the newly generated fly ash of the kiln, an increase in the concentration of Cd, K and Pb by 54%, 57% and 22%, respectively, was observed. In general, the operation of the rotary kiln was not impaired by the MSWI fly ash addition. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. The Lunar Dust Environment

    Science.gov (United States)

    Szalay, Jamey Robert

    Planetary bodies throughout the solar system are continually bombarded by dust particles, largely originating from cometary activities and asteroidal collisions. Surfaces of bodies with thick atmospheres, such as Venus, Earth, Mars and Titan are mostly protected from incoming dust impacts as these particles ablate in their atmospheres as 'shooting stars'. However, the majority of bodies in the solar system have no appreciable atmosphere and their surfaces are directly exposed to the flux of high speed dust grains. Impacts onto solid surfaces in space generate charged and neutral gas clouds, as well as solid secondary ejecta dust particles. Gravitationally bound ejecta clouds forming dust exospheres were recognized by in situ dust instruments around the icy moons of Jupiter and Saturn, and had not yet been observed near bodies with refractory regolith surfaces before NASA's Lunar Dust and Environment Explorer (LADEE) mission. In this thesis, we first present the measurements taken by the Lunar Dust Explorer (LDEX), aboard LADEE, which discovered a permanently present, asymmetric dust cloud surrounding the Moon. The global characteristics of the lunar dust cloud are discussed as a function of a variety of variables such as altitude, solar longitude, local time, and lunar phase. These results are compared with models for lunar dust cloud generation. Second, we present an analysis of the groupings of impacts measured by LDEX, which represent detections of dense ejecta plumes above the lunar surface. These measurements are put in the context of understanding the response of the lunar surface to meteoroid bombardment and how to use other airless bodies in the solar system as detectors for their local meteoroid environment. Third, we present the first in-situ dust measurements taken over the lunar sunrise terminator. Having found no excess of small grains in this region, we discuss its implications for the putative population of electrostatically lofted dust.

  7. Utilization of alternative fuels and materials in cement kiln towards emissions of benzene, toluene, ethyl-benzene and xylenes (BTEX

    Directory of Open Access Journals (Sweden)

    Muliane Ulfi

    2018-01-01

    Full Text Available Co-processing in cement industry has benefits for energy conservation and waste recycling. Nevertheless, emissions of benzene, toluene, ethyl-benzene, and xylenes (BTEX tend to increase compared to a non co-processing kiln. A study was conducted in kiln feeding solid AFR (similar to municipal solid waste, MSW having production capacity 4600-ton clinker/day (max. 5000 ton/day and kiln feeding biomass having production capacity 7800-ton clinker/day (max. 8000 ton/day. The concentration of VOCs emissions tends to be higher at the raw mill on rather than the raw mill off. At the raw mill on, concentration of total volatile organic carbon (VOCs emission from cement kiln stack feeding Solid AFR 1, biomass, Solid AFR 2, and mixture of Solid AFR and biomass is 16.18 mg/Nm3, 16.15 mg/Nm3, 9.02 mg/Nm3, and 14.11 mg/Nm3 respectively. The utilization of biomass resulted in the lower fraction of benzene and the higher fraction of xylenes in the total VOCs emission. Operating conditions such as thermal substitution rate, preheater temperature, and kiln speed are also likely to affect BTEX emissions.

  8. Modeling the Mixing of Components in a Rotary Kiln While Burning Municipal Waste to Ensure Rational Use of Energy

    Directory of Open Access Journals (Sweden)

    Krot O.P.

    2017-08-01

    Full Text Available In Ukraine municipal waste is collected and delivered to a landfill. Municipal waste can be used as fuel to generate additional heat and electricity. The primary advantages of incineration are that waste volumes are reduced by an estimated, and the need for land and landfill space is greatly reduced. The plant has been designed by North–East Scientific Center using a thermocatalytic waste gas purification system with highly efficient dioxins reduction and heat energy recovery system. The technology of waste neutralization includes: a rotary kiln, an afterburner chamber, a new catalytic technologies for the treatment, a heat exchanger for heating combustion air, supply of alkali solution into the gas-escape channel, a carbon fiber adsorption filter. The organization of the right process of waste mixing in the rotary kiln allows increasing the efficiency of combustion, to equalize the combustion temperatures of the components of the waste and the completeness of the burning out of hazardous substances, which reduces the risk of their getting into the ash. The goal of the research is to build an analytical mathematical model of mixing of components in a rotary kiln. The model is based on the mathematical apparatus of Markov chains. The model allows to determine the concentration of the key component in any elementary volume of material circulating in the rotary kiln at any time and to calculate the statistical characteristics of the homogeneity of the mixture. The model will be used to research new designs of the equipment with rotary kilns.

  9. Dust Devil Tracks

    Science.gov (United States)

    2002-01-01

    (Released 8 May 2002) The Science This image, centered near 50.0 S and 17.7 W displays dust devil tracks on the surface. Most of the lighter portions of the image likely have a thin veneer of dust settled on the surface. As a dust devil passes over the surface, it acts as a vacuum and picks up the dust, leaving the darker substrate exposed. In this image there is a general trend of many of the tracks running from east to west or west to east, indicating the general wind direction. There is often no general trend present in dust devil tracks seen in other images. The track patterns are quite ephemeral and can completely change or even disappear over the course of a few months. Dust devils are one of the mechanisms that Mars uses to constantly pump dust into the ubiquitously dusty atmosphere. This atmospheric dust is one of the main driving forces of the present Martian climate. The Story Vrrrrooooooooom. Think of a tornado, the cartoon Tasmanian devil, or any number of vacuum commercials that powerfully suck up swirls of dust and dirt. That's pretty much what it's like on the surface of Mars a lot of the time. Whirlpools of wind called

  10. New archaeomagnetic data from three roman kilns in northeast Spain: a contribution to the Iberian palaeosecular variation curve

    Science.gov (United States)

    Beamud, E.; Gómez-Paccard, M.; McIntosh, G.; Larrasoaña, J. C.

    2012-04-01

    New archaeomagnetic results from three kilns recovered from a roman age archaeological site in Badalona (northeast Spain) are reported. Archaeological evidences constrain the abandonment of kilns BC1 and BC2 between 0 and 50 yrs AD, whereas the abandonment of kiln BC3 is established between 50 and 150 yrs AD. In order to perform the archaeomagnetic study 12 to 14 samples per kiln were collected using a portable electrical drill with a water-cooled diamond bit, following standard palaeomagnetic sampling methods. Samples were distributed all around the combustion chambers, being obtained in different orientations from the burnt walls and central pillars. Rock magnetic measurements revealed a dominance of low titanium titanomagnetite or substituted magnetite as the main carrier of the magnetic signal and a minor contribution of maghemite. The presence of single domain material, along with the thermal stability of the samples, means that they are suitable candidates for archaeomagnetic studies, and in particular intensity determinations. Archaeomagnetic experiments were attempted on 32 specimens characterised by NRM intensities between 0.5 and 8.3 A/m. Mean archaeomagnetic directions and archaeointensities have been obtained from the original Thellier method with regular partial thermoremanent magnetisation (pTRM) checks being used to estimate archaeointensities. Mean intensities of 68.3 ± 4.2 µT, 72.4 ± 5.0 µT and 72.9 ± 3.7 µT were obtained for kilns BC1, BC2 and BC3, respectively. A cooling rate correction factor of 5% has been applied to mean intensities and the values obtained have been relocated to Paris and Madrid through the virtual dipole moment VDM. The mean directions of the characteristic magnetization of each kiln and their associated statistical parameters were derived from principal component analysis and Fisher statistics. Very similar directions were obtained for BC1 and BC2 with the circle of confidence (α95) of the BC2 direction falling within

  11. Evaluation of the release of dioxins and PCBs during kiln-firing of ball clay.

    Science.gov (United States)

    Broadwater, Kendra; Meeker, John D; Luksemburg, William; Maier, Martha; Garabrant, David; Demond, Avery; Franzblau, Alfred

    2014-01-01

    Ball clay is known to be naturally contaminated with high levels of polychlorinated di-benzo-p-dioxins (PCDDs). This study evaluated the potential for PCDD, polychlorinated dibenzofuran (PCDF) and polychlorinated biphenyl (PCB) release during the kiln firing of ball clay in an art studio. Toxic equivalence (TEQ) were calculated using World Health Organization (WHO) 2005 toxic equivalence factors (TEF) and congener concentrations. Ten bags of commercial ball clay were found to have an average TEQ of 1,370 nanograms/kilogram (ng kg(-1)) dry weight (dw), almost exclusively due to PCDDs (99.98% of TEQ). After firing, none of the 29 dioxin-like analytes was measured above the limits of detection (LOD) in the clay samples. Air samples were taken during firings using both low-flow and high-flow air samplers. Few low-flow air samples contained measurable levels of dioxin congeners above the LOD. The mean TEQ in the high volume air samples ranged from 0.07 pg m(-3) to 0.21 pg m(-3) when firing ball clay, and was 0.11 pg m(-3) when no clay was fired. These concentrations are within the range measured in typical residences and well-controlled industrial settings. The congener profiles in the high-flow air samples differed from the unfired clay; the air samples had a considerable contribution to the TEQ from PCDFs and PCBs. Given that the TEQs of all air samples were very low and the profiles differed from the unfired clay, it is likely that the PCDDs in dry ball clay were destroyed during kiln firing. These results suggest that inhalation of volatilized dioxins during kiln firing of dry ball clay is an unlikely source of exposure for vocational and art ceramicists. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Thermal energy analysis of a lime production process: Rotary kiln, preheater and cooler

    International Nuclear Information System (INIS)

    Shahin, Hamed; Hassanpour, Saeid; Saboonchi, Ahmad

    2016-01-01

    Highlights: • The integrated model for lime production unit which includes cooler, preheater and rotary kiln is developed. • The effect of residence time in each section on efficiency is investigated. • Influence of material feed rate and excess air on specific fuel consumption is analyzed. • The significant effect of particle size on efficiency and specific fuel consumption is shown. - Abstract: In this paper, thermal energy analysis of three zones of a lime production process, which are preheater, rotary kiln and cooler, is performed. In order to perform a proper quantitative estimation, the system was modeled using energy balance equations including coupled heat transfer and chemical reaction mechanisms. A mathematical model was developed, and consequently, the thermal and chemical behavior of limestone was investigated. The model was verified using empirical data. After model confirmation, the variation of Specific Fuel Consumption (SFC) versus production rate was predicted and the optimum condition was determined. Subsequently, fuel consumption was calculated regarding to altered residence time inside each zone of lime production process, for a constant output. Results indicate that increasing the residence time inside each zone of lime production process, will enhance thermal efficiency and saves fuel consumption. Relative enhancement will be the same for different sizes of limestone. It was found that a 10-min increase in material residence time inside the preheater or rotary kiln can reduce fuel consumption by around two percent. Whereas, a 5-min increase in material residence time inside the cooler would be enough to obtain a similar result. Finally, the ratio of air-to-fuel and production rate are changed in such a way that the same product is achieved. The model predicts that lowering excess air from 15% to 10% leads to a 2.5% reduction of Specific Fuel Consumption (SFC).

  13. Whither Cometary Dust?

    Science.gov (United States)

    Lisse, Carey M.

    2010-10-01

    In this paper I will discuss recent findings that have important implications for our understanding of the formation and evolution of primitive solar system dust, including: - Nesvorny et al. (2010), following up on their dynamical analyses of the zodiacal dust bands as sourced by the breakup of the Karin (5Mya) and Veritas (8Mya) asteroid families, argue that over 90% of the interplanetary dust cloud at 1 AU comes from JFC comets with near-circularized, low inclination orbits. This implies that the noted IPD collections of anhydrous and hydrous dust particles are likely to be from Oort cloud and JFC comets, respectively, not from asteroids and comets as thought in the past. Hydrous dust particles from comets like 85P/Wild2 and 9P/Tempel 1 would be consistent with results from the STARDUST and Deep Impact experiments. - Estimates of the dust particle size distributions (PSDs) in the comae of 85P/Wild2 (Green et al. 2004, 2007) and 73P/SW-3 (Sitko et al. 2010, Vaubaillon & Reach 2010) and in the trails of comets (Reach et al. 2007) have broken power law structure, with a plateau enhancement of particles of 1 mm - 1 cm in size. This size is also the size of most chondritic inclusions, and the predicted size range of the "aggregational barrier", where collisions between dust particles become destructive. - Studies of the albedo and polarization properties of cometary dust (Kolokolova et al. 2007) suggest there are 2 major groupings, one with low scattering capability and one with high. While these families could possibly have been explained by systematics in the PSDs of the emitted dust, independent work by Lisse et al. (2008) on the mineralogy of a number of highly dusty comets has shown evidence for one family of comets with highly crystalline dust and another with highly amorphous dust.

  14. White-and-blud porcelain of Hutian kiln in Ming dynasty studied by PIXE

    International Nuclear Information System (INIS)

    Cheng Lin; Feng Songlin; Sha Yin; Cheng Huansheng

    2004-01-01

    The study of provenance, ages and distinguishing precious ancient porcelain from a fake of Chinese ancient porcelain by modern technologies arose greatly interesting in the circles of archaeologists and scientists in China. Concentration of major and trace elements of white-and-blue porcelain of Hutian kiln in Ming Dynasty were analyzed by PIXE, and elemental distributions of porcelain were analyzed by SPM. The results indicate the elemental distributions in the white glaze, blue glaze and body are homogeneous, respectively. It is a layer nearly 5-10 μm between the body and blue glaze. Probably, cobalt blue pigment used in the blue glaze comes from Jiangxi, Fujian province etc. (authors)

  15. New archeointensity results from the reconstructed ancient kiln by the Tsunakawa-Shaw method

    Science.gov (United States)

    Yamamoto, Y.; Hatakeyama, T.; Kitahara, Y.; Saito, T.

    2017-12-01

    Yamamoto et al. (2015) reported that baked clay samples from the floor of a reconstructed ancient kiln provided a reliable Tsunakawa-Shaw (LTD-DHT Shaw) archeointensity (AI) estimate of 47.3 +/- 2.2 microT which is fairly consistent with the in situ geomagnetic field of 46.4 microT at the time of the reconstruction. The reconstruction was conducted to reproduce an excavated kiln of the seventh century in Japan and Sue-type potteries of contemporary style were also fired (Nakajima et al., 1974). Two of the potteries with reddish color were recently subjected to the Tsunakawa-Shaw archeointensity determinations, resulting in reliable AI estimates of 45.4 +/- 2.3 (N=6) and 48.2 +/- 2.7 microT (N=15) when specimens were heated in air in laboratory (Yamamoto et al., 2017 JpGU-AGU Joint Meeting). We have had another opportunity to take samples from a new reconstructed ancient kiln in Japan which was fired in autumn 2016. The samples were two Sue-type potteries with grayish color (bowl-type and plate-type) and some blocks collected from inner wall of the kiln body. They were cut into mini specimens and then subjected to the Tsunakawa-Shaw experiment. Heating in laboratory was done either in air or vacuum.For the bowl-type pottery, AIs of 46.9 +/- 2.8 (N=6, air) and 45.3 +/- 2.3 microT (N=6, vacuum) are obtained. They are indistinguishable each other and consistent with the IGRF field of 47.4 microT at the reconstructed location in 2016. For the plate-type pottery, AIs result in 41.8 +/- 1.3 (N=4, air) and 43.9 +/- 3.9 microT (N=4, vacuum). They are also indistinguishable each other but the former AI is slightly lower than the IGRF field.For the inner wall, AIs of 45.0 (N=1, air) and 46.8 microT (N=1, vacuum) are obtained from a right-side wall, and those of 45.5 +/- 2.5 (N=2, air) and 47.7 +/- 3.0 microT (N=2, vacuum) are observed from a left-side wall. They are all indistinguishable and consistent with the IGRF field.

  16. Validity of archaeomagnetic field recording: an experimental pottery kiln at Coppengrave, Germany

    Science.gov (United States)

    Schnepp, Elisabeth; Leonhardt, Roman; Korte, Monika; Klett-Drechsel, Johannes

    2016-04-01

    Palaeomagnetic data obtained from archaeological materials are used for reconstructions of the Earth's magnetic field of the past millennia. While many studies tested the reliability of this recorder for palaeointensity only a few studies did this for direction. The study presents an archaeomagnetic and rock magnetic investigation applied to an experimental pottery kiln, which was operated in 2003 to produce stone ware. This kind of high-quality pottery needs a temperature of at least 1160 °C. Shortly before heating of the kiln direct absolute measurements of the absolute geomagnetic field vector have been carried out close to it. After cooling of the kiln 24 oriented palaeomagnetic samples have been taken. Although Curie temperatures are about 580 °C, that is the typical temperature for magnetite, thermal as well as alternating field demagnetisations reveal also a considerable amount of hematite as magnetic carrier. This mixture of magnetite and hematite is dominated by pseudo-single domain grains. Demagnetisation removed in some cases weak secondary components, but in most cases the specimens carried a single component thermoremanent magnetisation. The mean characteristic remanent magnetisation direction agrees on 95 per cent confidence level with the directly measured field direction. Archaeointensity was obtained from five specimens with the Thellier-Coe method and with the multiple-specimen palaeointensity domain-state corrected method. Six of these specimens also provided a result of the Dekkers-Böhnel method, which overestimated the archaeointensity by about 9 per cent compared to the direct value, while after correction for fraction the value agrees very well. For the multiple-specimen palaeointensity domain-state corrected method only fractions between 25 and 75 per cent have been used and specimens showing alteration have been excluded. Above 450 °C many specimens showed alteration of the magnetic grains. Because median destructive temperatures were

  17. A methodological proposal for ancient kiln simulation analyzed by Moessbauer spectroscopy

    International Nuclear Information System (INIS)

    Flores, E.; Fernandes, B.; Flores, E.; Fernandez, B.

    1988-01-01

    In previous papers scientistis from different countries have reported simulating incomplete methodologies for ancient kiln firing conditions. Results from clays fired in a first working hypothesis are presented to end as a methodological proposal for simulation. This study was done through Moessbauer spectroscopy. The fired clay used presented a Fe 2+ and Fe 3+ spectrum in octahedric sites. Moessbauer parameters complemented by other studies indicate illite is the predominant clay mineral. A trait of the parameters behaviour in presence of temperature is reported. (author)

  18. Internet and Fuzzy Based Control System for Rotary Kiln in Cement Manufacturing Plant

    Directory of Open Access Journals (Sweden)

    Hanane Zermane

    2017-01-01

    Full Text Available This paper develops an Internet-based fuzzy control system for an industrial process plant to ensure the remote and fuzzy control in cement factories in Algeria. The remote process consists of control, diagnosing alarms occurs, maintaining and synchronizing different regulation loops. Fuzzy control of the kiln ensures that the system be operational at all times, with minimal downtime. Internet technology ensures remote control. The system reduces downtimes and can guided by operators in the main control room or via Internet.

  19. Climate change-induced heat risks for migrant populations working at brick kilns in India: a transdisciplinary approach

    Science.gov (United States)

    Lundgren-Kownacki, Karin; Kjellberg, Siri M.; Gooch, Pernille; Dabaieh, Marwa; Anandh, Latha; Venugopal, Vidhya

    2018-03-01

    During the summer of 2015, India was hit by a scorching heat wave that melted pavements in Delhi and caused thousands of deaths, mainly among the most marginalized populations. One such group facing growing heat risks from both occupational and meteorological causes are migrant brick kiln workers. This study evaluates both current heat risks and the potential future impacts of heat caused by climate change, for the people working at brick kilns in India. A case study of heat stress faced by people working at brick kilns near Chennai, India, is the anchor point around which a transdisciplinary approach was applied. Around Chennai, the situation is alarming since occupational heat exposure in the hot season from March to July is already at the upper limits of what humans can tolerate before risking serious impairment. The aim of the study was to identify new pathways for change and soft solutions by both reframing the problem and expanding the solution space being considered in order to improve the quality of life for the migrant populations at the brick kilns. Technical solutions evaluated include the use of sun-dried mud bricks and other locally "appropriate technologies" that could mitigate the worsening of climate change-induced heat. Socio-cultural solutions discussed for empowering the people who work at the brick kilns include participatory approaches such as open re-localization, and rights-based approaches including the environmental sustainability and the human rights-based approach framework. Our analysis suggests that an integrative, transdisciplinary approach could incorporate a more holistic range of technical and socio-culturally informed solutions in order to protect the health of people threatened by India's brick kiln industry.

  20. Communication plan for windblown dust.

    Science.gov (United States)

    2015-05-01

    Windblown dust events occur in Arizona, and blowing dust has been considered a contributing factor to serious crashes on the : segment of Interstate 10 (I10) between Phoenix and Tucson, as well as on other Arizona roadways. Arizonas dust events...

  1. Charcoal kiln sites, associated landscape attributes and historic forest conditions: DTM-based investigations in Hesse (Germany

    Directory of Open Access Journals (Sweden)

    Marcus Schmidt

    2016-03-01

    Full Text Available Background An examination of the distribution of ancient charcoal kiln sites in the forest landscape seems to be worthwhile, since general trends in the selection of suitable kiln site locations in the past might become obvious. In this way forest landscape elements with a more intense usage by charcoal burning can be identified. By doing this, we can expect to gain information on the former condition and tree species composition of woodland. Investigations on the spatial distribution of charcoal kiln sites in relation to landscape attributes are sparse, however, probably due to the high on-site mapping effort. The outstanding suitability of LiDAR-derived digital terrain models (DTMs for the detection of charcoal kiln sites has been recently proved. Hence, DTM-based surveys of charcoal kiln sites represent a promising attempt to fill this research gap. Methods Based on DTM-based surveys, we analyzed the spatial distribution of charcoal kiln sites in two forest landscapes in the German federal state of Hesse: Reinhardswald and Kellerwald-Edersee National Park. In doing so, we considered the landscape attibutes "tree species composition", “water supply status”, “nutrient supply status”, “soil complex classes”, “altitude”, “exposition”, and “inclination”. Results We found that charcoal kiln sites were established preferably on hillside locations that provided optimal growing and regeneration conditions for European beech (Fagus sylvatica due to their acidic brown soils and sufficient water supply. These results are in line with instructions for the selection of appropriate kiln site locations, found in literature from the 18th to the 19th century. Conclusions We conclude that there were well-stocked, beech-dominated deciduous forest stands in northern Hesse before 1800, particularly at poorly accessible hillside locations. These large stocks of beech wood were utilized by the governments of the different Hessian territories

  2. Emissions and Char Quality of Flame-Curtain "Kon Tiki" Kilns for Farmer-Scale Charcoal/Biochar Production

    Science.gov (United States)

    Cornelissen, Gerard; Pandit, Naba Raj; Taylor, Paul; Pandit, Bishnu Hari; Sparrevik, Magnus; Schmidt, Hans Peter

    2016-01-01

    Flame Curtain Biochar Kilns Pyrolysis of organic waste or woody materials yields charcoal, a stable carbonaceous product that can be used for cooking or mixed into soil, in the latter case often termed "biochar". Traditional kiln technologies for charcoal production are slow and without treatment of the pyrolysis gases, resulting in emissions of gases (mainly methane and carbon monoxide) and aerosols that are both toxic and contribute to greenhouse gas emissions. In retort kilns pyrolysis gases are led back to a combustion chamber. This can reduce emissions substantially, but is costly and consumes a considerable amount of valuable ignition material such as wood during start-up. To overcome these problems, a novel type of technology, the Kon-Tiki flame curtain pyrolysis, is proposed. This technology combines the simplicity of the traditional kiln with the combustion of pyrolysis gases in the flame curtain (similar to retort kilns), also avoiding use of external fuel for start-up. Biochar Characteristics A field study in Nepal using various feedstocks showed char yields of 22 ± 5% on a dry weight basis and 40 ± 11% on a C basis. Biochars with high C contents (76 ± 9%; n = 57), average surface areas (11 to 215 m2 g-1), low EPA16—PAHs (2.3 to 6.6 mg kg-1) and high CECs (43 to 217 cmolc/kg)(average for all feedstocks, mainly woody shrubs) were obtained, in compliance with the European Biochar Certificate (EBC). Gas Emission Factors Mean emission factors for the flame curtain kilns were (g kg-1 biochar for all feedstocks); CO2 = 4300 ± 1700, CO = 54 ± 35, non-methane volatile organic compounds (NMVOC) = 6 ± 3, CH4 = 30 ± 60, aerosols (PM10) = 11 ± 15, total products of incomplete combustion (PIC) = 100 ± 83 and NOx = 0.4 ± 0.3. The flame curtain kilns emitted statistically significantly (p<0.05) lower amounts of CO, PIC and NOx than retort and traditional kilns, and higher amounts of CO2. Implications With benefits such as high quality biochar, low emission

  3. Dust in planetary nebulae

    International Nuclear Information System (INIS)

    Mathis, J.S.

    1978-01-01

    The author's review concentrates on theoretical aspects of dust in planetary nebulae (PN). He considers the questions: how much dust is there is PN; what is its composition; what effects does it have on the ionization structure, on the dynamics of the nebula. (Auth.)

  4. Toxicity of lunar dust

    NARCIS (Netherlands)

    Linnarsson, D.; Carpenter, J.; Fubini, B.; Gerde, P.; Loftus, D.; Prisk, K.; Staufer, U.; Tranfield, E.; van Westrenen, W.

    2012-01-01

    The formation, composition and physical properties of lunar dust are incompletely characterised with regard to human health. While the physical and chemical determinants of dust toxicity for materials such as asbestos, quartz, volcanic ashes and urban particulate matter have been the focus of

  5. Combustible dust tests

    Science.gov (United States)

    The sugar dust explosion in Georgia on February 7, 2008 killed 14 workers and injured many others (OSHA, 2009). As a consequence of this explosion, OSHA revised its Combustible Dust National Emphasis (NEP) program. The NEP targets 64 industries with more than 1,000 inspections and has found more tha...

  6. Respirable dust measured downwind during rock dust application.

    Science.gov (United States)

    Harris, M L; Organiscak, J; Klima, S; Perera, I E

    2017-05-01

    The Pittsburgh Mining Research Division of the U.S. National Institute for Occupational Safety and Health (NIOSH) conducted underground evaluations in an attempt to quantify respirable rock dust generation when using untreated rock dust and rock dust treated with an anticaking additive. Using personal dust monitors, these evaluations measured respirable rock dust levels arising from a flinger-type application of rock dust on rib and roof surfaces. Rock dust with a majority of the respirable component removed was also applied in NIOSH's Bruceton Experimental Mine using a bantam duster. The respirable dust measurements obtained downwind from both of these tests are presented and discussed. This testing did not measure miners' exposure to respirable coal mine dust under acceptable mining practices, but indicates the need for effective continuous administrative controls to be exercised when rock dusting to minimize the measured amount of rock dust in the sampling device.

  7. Lunar Dust Mitigation Screens

    Science.gov (United States)

    Knutson, Shawn; Holloway, Nancy

    With plans for the United States to return to the moon, and establish a sustainable human presence on the lunar surface many issues must be successfully overcome. Lunar dust is one of a number of issues with the potential to create a myriad of problems if not adequately addressed. Samples of dust brought back from Apollo missions show it to be soft, yet sharp and abrasive. The dust consists of a variety of morphologies including spherical, angular blocks, shards, and a number of irregular shapes. One of the main issues with lunar dust is its attraction to stick to anything it comes in contact with (i.e. astronauts, equipment, habitats, etc.). Ionized radiation from the sun strikes the moon's surface and creates an electrostatic charge on the dust. Further, the dust harbors van der Waals forces making it especially difficult to separate once it sticks to a surface. During the Apollo missions, it was discovered that trying to brush the lunar dust from spacesuits was not effective, and rubbing it caused degradation of the suit material. Further, when entering the lunar module after moonwalks, the astronauts noted that the dust was so prolific inside the cabin that they inhaled and ingested it, causing at least one of them, Harrison "Jack" Schmidt, to report irritation of the throat and lungs. It is speculated that the dust could also harm an astronaut's nervous and cardiovascular systems, especially during an extended stay. In addition to health issues, the dust can also cause problems by scouring reflective coatings off of thermal blankets, and roughening surfaces of windows and optics. Further, panels on solar cells and photovoltaics can also be compromised due to dust sticking on the surfaces. Lunar dust has the capacity to penetrate seals, interfere with connectors, as well as mechanisms on digging machines, all of which can lead to problems and failure. To address lunar dust issues, development of electrostatic screens to mitigate dust on sur-faces is currently

  8. Effect of flue gas recirculation during oxy-fuel combustion in a rotary cement kiln

    International Nuclear Information System (INIS)

    Granados, David A.; Chejne, Farid; Mejía, Juan M.; Gómez, Carlos A.; Berrío, Ariel; Jurado, William J.

    2014-01-01

    The effect of Flue Gas Recirculation (FGR) during Oxy-Fuel Combustion in a Rotary Cement Kiln was analyzed by using a CFD model applied to coal combustion process. The CFD model is based on 3D-balance equations for mass, species, energy and momentum. Turbulence and radiation model coupled to a chemical kinetic mechanism for pyrolysis processes, gas–solid and gas–gas reactions was included to predicts species and flame temperature distribution, as well as convective and radiation energy fluxes. The model was used to study coal combustion with air and with oxygen for FGR between 30 and 85% as controller parameter for temperature in the process. Flame length effect and heat transfer by convection and radiation to the clinkering process for several recirculation ratios was studied. Theoretical studies predicted a located increase of energy flux and a reduction in flame length with respect to the traditional system which is based on air combustion. The impact of FGR on the oxy-fuel combustion process and different energy scenarios in cement kilns to increase energy efficiency and clinker production were studied and evaluated. Simulation results were in close agreement with experimental data, where the maximum deviation was 7%

  9. Degradation of Alumina and Magnesia Chrome refractory bricks in Portland cement kiln – Corrected version*

    Directory of Open Access Journals (Sweden)

    Ben Addi K.

    2014-05-01

    Full Text Available In cement plants, the refractory products are particularly confronted to partially liquid oxide phases at temperature ranging between 900°C and 1700°C. All constituents of these products have to resist not only to thermal constraints, but also to the thermochemical solicitations which result from contact material/coating. In order to study the phenomenon of degradation of refractory bricks in cement kilns and to identify the causes of their degradation, we proceed to the examination of industrial cases in cement kiln. Many chemical tests of the degraded refractory bricks have been done and the results acquired were compared to the ones not used. The analysis of the results is doing using different techniques (Loss of ignition, X-ray Fluorescence, X-ray Diffraction. The results show that the degradation of the used bricks in the clinkering and cooling zone is due to the infiltration of aggressive elements such us sulphur, alkali (Na2O, K2O .... The chemical interaction between the Portland clinker phases and refractory material has also an importance on the stability of the coating and consequently on the life of the refractories.

  10. Life cycle assessment of the use of alternative fuels in cement kilns: A case study.

    Science.gov (United States)

    Georgiopoulou, Martha; Lyberatos, Gerasimos

    2018-06-15

    The benefits of using alternative fuels (AFs) in the cement industry include reduction of the use of non-renewable fossil fuels and lower emissions of greenhouse gases, since fossil fuels are replaced with materials that would otherwise be degraded or incinerated with corresponding emissions and final residues. Furthermore, the use of alternative fuels maximizes the recovery of energy. Seven different scenaria were developed for the production of 1 ton of clinker in a rotary cement kiln. Each of these scenaria includes the use of alternative fuels such as RDF (Refuse derived fuel), TDF (Tire derived fuel) and BS (Biological sludge) or a mixture of them, in partial replacement of conventional fuels such as coal and pet coke. The purpose of this study is to evaluate the environmental impacts of the use of alternative fuels in relation to conventional fuels in the kiln operation. The Life Cycle Assessment (LCA) methodology is used to quantify the potential environmental impacts in each scenario. The interpretation of the results provides the conclusion that the most environmentally friendly prospect is the scenario based on RDF while the less preferable scenario is the scenario based on BS. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Energy and exergy analysis of an annular shaft kiln with opposite burners

    International Nuclear Information System (INIS)

    Rong, Wenjie; Li, Baokuan; Qi, Fengsheng; Cheung, Sherman C.P.

    2017-01-01

    Highlights: • An OBASK is investigated for the energy and exergy performance. • The energy and exergy efficiency of the OBASK is of 63.6% and 35.7%, respectively. • The exergy destruction accounts for 44.5% of the total exergy input. - Abstract: Annular shaft kilns with opposite burners (OBASK) has been widely adopted due to the advantages of cost saving and easy controlling. Nonetheless, compared with the traditional annular shaft kiln, the OBASK is not favorable in terms of thermal performance and energy efficiency. Aiming to improve the thermal performance, a comprehensive energy and exergy analysis of an OBASK has been conducted based on the actual operational data obtained from on-site measurements. For making a thorough thermal analysis of the OBASK, special attentions have been focused in considering magnesium decomposition reaction and moisture in limestone in the methodology. The energy and exergy efficiencies are determined to be 63.6% and 35.7%, respectively. The exergy destruction is 44.0% of total exergy input of which fuel combustion causes 56.6% of the exergy destruction. Furthermore, the effects of CaO and moisture contents in limestone on energy and exergy efficiencies are analyzed. The results have demonstrated the potential energy saving of the OBASK and identified three proposed energy conservation measures. Improvement and effect of the three proposed measures on the thermal performance are verified via further analysis.

  12. Thermal Behavior of Coal Used in Rotary Kiln and Its Combustion Intensification

    Directory of Open Access Journals (Sweden)

    Qiang Zhong

    2018-04-01

    Full Text Available Pyrolysis and combustion behaviors of three coals (A, B, and C coals were investigated and their combustion kinetics were calculated by the Freeman–Carroll method to obtain quantitative insight into their combustion behaviors. Moreover, the effects of coal size, air flow, oxygen content, and heating rate on coal combustion behaviors were analyzed. Results showed that the three coals have a similar trend of pyrolysis that occurs at about 670 K and this process continuously proceeds along with their combustion. Combustion characteristics and kinetic parameters can be applied to analyze coal combustion behaviors. Three coals having combustion characteristics of suitable ignition temperature (745–761 K, DTGmax (14.20–15.72%/min, and burnout time (7.45–8.10 min were analyzed in a rotary kiln. Combustion kinetic parameters provide quantitative insights into coal combustion behavior. The suitable particle size for coal combustion in a kiln is that the content of less than 74 μm is 60% to 80%. Low activation energy and reaction order make coal, especially C coal, have a simple combustion mechanism, great reactivity, be easily ignited, and a low peak temperature in the combustion state. Oxygen-enrichment and high heating rates enhance coal combustion, increasing combustion intensity and peak value, thus shortening burnout time.

  13. CFD SIMULATION FOR DEMILITARIZATION OF RDX IN A ROTARY KILN BY THERMAL DECOMPOSITION

    Directory of Open Access Journals (Sweden)

    SI H. LEE

    2017-06-01

    Full Text Available Demilitarization requires the recovery and disposal of obsolete ammunition and explosives. Since open burning/detonation of hazardous waste has caused serious environmental and safety problems, thermal decomposition has emerged as one of the most feasible methods. RDX is widely used as a military explosive due to its high melting temperature and detonation power. In this work, the feasible conditions under which explosives can be safely incinerated have been investigated via a rotary kiln simulation. To solve this problem, phase change along with the reactions of RDX has been incisively analyzed. A global reaction mechanism consisting of condensed phase and gas phase reactions are used in Computational Fluid Dynamics simulation. User Defined Functions in FLUENT is utilized in this study to inculcate the reactions and phase change into the simulation. The results divulge the effect of temperature and the varying amounts of gas produced in the rotary kiln during the thermal decomposition of RDX. The result leads to the prospect of demilitarizing waste explosives to avoid the possibility of detonation.

  14. Ways to achieve optimum utilization of waste gas heat in cement kiln plants with cyclone preheaters

    Energy Technology Data Exchange (ETDEWEB)

    Steinbiss, E

    1986-02-01

    Kiln exit gases and the exhaust gases from clinker coolers often cannot be fully utilized in drying plants. In such cases a part of the heat content of the gases should be utilized for water heating. In addition, it is possible to utilize the waste gas heat in conventional steam boilers, with which, depending on design, it is possible to generate electricity at a rate of between 10-30 kWh/t (net output). A new and promising method of utilization of waste gas heat is provided by precalcining systems with bypass, in which up to 100% of the kiln exit gases can be economically bypassed and be utilized in a steam boiler, without requiring any cooling. A development project, already started, gives information on the operational behaviour of such a plant and on the maximum energy recoverable. Alternatively, the bypass gases may, after partial cooling with air or preheater exit gas, be dedusted and then utilized in a grinding/drying plant. Furthermore, they can be used in the cement grinding process for the drying of wet granulated blastfurnace slag or other materials. For this it is not necessary to dedust the bypass gases.

  15. Quantifying Anthropogenic Dust Emissions

    Science.gov (United States)

    Webb, Nicholas P.; Pierre, Caroline

    2018-02-01

    Anthropogenic land use and land cover change, including local environmental disturbances, moderate rates of wind-driven soil erosion and dust emission. These human-dust cycle interactions impact ecosystems and agricultural production, air quality, human health, biogeochemical cycles, and climate. While the impacts of land use activities and land management on aeolian processes can be profound, the interactions are often complex and assessments of anthropogenic dust loads at all scales remain highly uncertain. Here, we critically review the drivers of anthropogenic dust emission and current evaluation approaches. We then identify and describe opportunities to: (1) develop new conceptual frameworks and interdisciplinary approaches that draw on ecological state-and-transition models to improve the accuracy and relevance of assessments of anthropogenic dust emissions; (2) improve model fidelity and capacity for change detection to quantify anthropogenic impacts on aeolian processes; and (3) enhance field research and monitoring networks to support dust model applications to evaluate the impacts of disturbance processes on local to global-scale wind erosion and dust emissions.

  16. Spirit Feels Dust Gust

    Science.gov (United States)

    2007-01-01

    On sol 1149 (March 28, 2007) of its mission, NASA's Mars Exploration Rover Spirit caught a wind gust with its navigation camera. A series of navigation camera images were strung together to create this movie. The front of the gust is observable because it was strong enough to lift up dust. From assessing the trajectory of this gust, the atmospheric science team concludes that it is possible that it passed over the rover. There was, however, no noticeable increase in power associated with this gust. In the past, dust devils and gusts have wiped the solar panels of dust, making it easier for the solar panels to absorb sunlight.

  17. Use of lignite in the production of sponge iron and processing of waste oxides in rotary kilns

    Energy Technology Data Exchange (ETDEWEB)

    Eichberger, H; Schnabel, W; Serbent, H

    1978-11-01

    Based on a study of the situation of fossil energy reserves, processes are described in which non-coking coals, in particular lignite, are used for reduction in the rotary kiln, i.e. for sponge iron production and for zinc volatilization from waste oxides).

  18. Hydrogen fluoride effects on local mung bean and maize cereal crops from peri-urban brick kilns in south asia

    NARCIS (Netherlands)

    Ahmad, M.N.; Ahmad, S.S.; Zia, A.; Iqbal, M.S.; Shah, H.; Mian, A.A.; Shah, R.U.

    2014-01-01

    Increased urbanisation throughout South Asia has increased the number and output of the brick kilns that typically surround major cities, but the environmental and health impacts of their atmospheric emissions are poorly understood in Pakistan. We report the negative effects of hydrogen fluoride

  19. A SYSTEM AND A METHOD FOR PREDICTION OF NOx EMISSION AND/OR FREE LIME CONCENTRATION IN A CEMENT KILN

    DEFF Research Database (Denmark)

    2008-01-01

    The invention relates to a method (and corresponding soft sensor) for determining one or more cement kiln process parameters, the method comprising the steps of collecting at least one process measurement representing at least one process parameter and collecting at least one item of image data r...

  20. Dynamic Analysis of the Temperature and the Concentration Profiles of an Industrial Rotary Kiln Used in Clinker Production

    Directory of Open Access Journals (Sweden)

    DIULIA C.Q. RODRIGUES

    Full Text Available ABSTRACT Cement is one of the most used building materials in the world. The process of cement production involves numerous and complex reactions that occur under different temperatures. Thus, there is great interest in the optimization of cement manufacturing. Clinker production is one of the main steps of cement production and it occurs inside the kiln. In this paper, the dry process of clinker production is analysed in a rotary kiln that operates in counter flow. The main phenomena involved in clinker production is as follows: free residual water evaporation of raw material, decomposition of magnesium carbonate, decarbonation, formation of C3A and C4AF, formation of dicalcium silicate, and formation of tricalcium silicate. The main objective of this study was to propose a mathematical model that realistically describes the temperature profile and the concentration of clinker components in a real rotary kiln. In addition, the influence of different speeds of inlet gas and solids in the system was analysed. The mathematical model is composed of partial differential equations. The model was implemented in Mathcad (available at CCA/UFES and solved using industrial input data. The proposal model is satisfactory to describe the temperature and concentration profiles of a real rotary kiln.

  1. Dynamic Analysis of the Temperature and the Concentration Profiles of an Industrial Rotary Kiln Used in Clinker Production.

    Science.gov (United States)

    Rodrigues, Diulia C Q; Soares, Atílio P; Costa, Esly F; Costa, Andréa O S

    2017-01-01

    Cement is one of the most used building materials in the world. The process of cement production involves numerous and complex reactions that occur under different temperatures. Thus, there is great interest in the optimization of cement manufacturing. Clinker production is one of the main steps of cement production and it occurs inside the kiln. In this paper, the dry process of clinker production is analysed in a rotary kiln that operates in counter flow. The main phenomena involved in clinker production is as follows: free residual water evaporation of raw material, decomposition of magnesium carbonate, decarbonation, formation of C3A and C4AF, formation of dicalcium silicate, and formation of tricalcium silicate. The main objective of this study was to propose a mathematical model that realistically describes the temperature profile and the concentration of clinker components in a real rotary kiln. In addition, the influence of different speeds of inlet gas and solids in the system was analysed. The mathematical model is composed of partial differential equations. The model was implemented in Mathcad (available at CCA/UFES) and solved using industrial input data. The proposal model is satisfactory to describe the temperature and concentration profiles of a real rotary kiln.

  2. 40 CFR 63.1204 - What are the standards for hazardous waste burning cement kilns that are effective until...

    Science.gov (United States)

    2010-07-01

    ... Principal Organic Hazardous Constituents (POHCs) in the waste feed that you specify under paragraph (c)(3... in the hazardous waste feed, considering the results of hazardous waste analyses or other data and... waste burning cement kilns that are effective until compliance with the standards under § 63.1220? 63...

  3. THE FATE OF TRACE METALS IN A ROTARY KILN INCINERATOR WITH A VENTURI/PACKED COLUMN SCRUBBER - VOLUME II: APPENDICES

    Science.gov (United States)

    A 5-week series of pilot-scale incineration tests, employing a synthetic waste feed, was performed at the U.S. Environmental Protection Agency's Incineration Research Facility to evaluate the fate of trace metals fed to a rotary kiln incinerator equipped with a venturi scrubber/p...

  4. Thermodynamic analysis of the selective chlorination of electric arc furnace dust

    International Nuclear Information System (INIS)

    Pickles, C.A.

    2009-01-01

    The remelting of automobile scrap in an electric arc furnace (EAF) results in the production of a dust, which contains high concentrations of the oxides of zinc, iron, calcium and other metals. Typically, the lead and zinc are of commercial value, while the other metals are not worth recovering. At the present time, EAF dusts are treated in high temperature Waelz rotary kiln-type processes, where the lead and zinc oxides are selectively reduced and simultaneously reoxidized and a crude zinc oxide is produced. Another alternative processing route is selective chlorination, in which the non-ferrous metals are preferentially chlorinated to their gaseous chlorides and in this manner separated from the iron. In the present research, a detailed thermodynamic analysis of this chlorination process has been performed and the following factors were investigated; temperature, amount of chlorine, lime content, silica content, presence of an inert gas and the oxygen potential. High lead and zinc recoveries as gaseous chlorides could be achieved but some of the iron oxide was also chlorinated. Additionally, the calcium oxide in the dust consumes chlorine, but this can be minimized by adding silica, which results in the formation of stable calcium silicates. The optimum conditions were determined for a typical dust composition. The selectivities achieved with chlorination were lower than those for reduction, as reported in the literature, but there are other advantages such as the potential recovery of copper.

  5. Thermodynamic analysis of the selective chlorination of electric arc furnace dust

    Energy Technology Data Exchange (ETDEWEB)

    Pickles, C.A., E-mail: pickles-c@mine.queensu.ca [Department of Mining Engineering, Queen' s University, Kingston, Ontario, K7L 3N6 (Canada)

    2009-07-30

    The remelting of automobile scrap in an electric arc furnace (EAF) results in the production of a dust, which contains high concentrations of the oxides of zinc, iron, calcium and other metals. Typically, the lead and zinc are of commercial value, while the other metals are not worth recovering. At the present time, EAF dusts are treated in high temperature Waelz rotary kiln-type processes, where the lead and zinc oxides are selectively reduced and simultaneously reoxidized and a crude zinc oxide is produced. Another alternative processing route is selective chlorination, in which the non-ferrous metals are preferentially chlorinated to their gaseous chlorides and in this manner separated from the iron. In the present research, a detailed thermodynamic analysis of this chlorination process has been performed and the following factors were investigated; temperature, amount of chlorine, lime content, silica content, presence of an inert gas and the oxygen potential. High lead and zinc recoveries as gaseous chlorides could be achieved but some of the iron oxide was also chlorinated. Additionally, the calcium oxide in the dust consumes chlorine, but this can be minimized by adding silica, which results in the formation of stable calcium silicates. The optimum conditions were determined for a typical dust composition. The selectivities achieved with chlorination were lower than those for reduction, as reported in the literature, but there are other advantages such as the potential recovery of copper.

  6. Thermodynamic analysis of the selective chlorination of electric arc furnace dust.

    Science.gov (United States)

    Pickles, C A

    2009-07-30

    The remelting of automobile scrap in an electric arc furnace (EAF) results in the production of a dust, which contains high concentrations of the oxides of zinc, iron, calcium and other metals. Typically, the lead and zinc are of commercial value, while the other metals are not worth recovering. At the present time, EAF dusts are treated in high temperature Waelz rotary kiln-type processes, where the lead and zinc oxides are selectively reduced and simultaneously reoxidized and a crude zinc oxide is produced. Another alternative processing route is selective chlorination, in which the non-ferrous metals are preferentially chlorinated to their gaseous chlorides and in this manner separated from the iron. In the present research, a detailed thermodynamic analysis of this chlorination process has been performed and the following factors were investigated; temperature, amount of chlorine, lime content, silica content, presence of an inert gas and the oxygen potential. High lead and zinc recoveries as gaseous chlorides could be achieved but some of the iron oxide was also chlorinated. Additionally, the calcium oxide in the dust consumes chlorine, but this can be minimized by adding silica, which results in the formation of stable calcium silicates. The optimum conditions were determined for a typical dust composition. The selectivities achieved with chlorination were lower than those for reduction, as reported in the literature, but there are other advantages such as the potential recovery of copper.

  7. Galactic dust and extinction

    International Nuclear Information System (INIS)

    Lyngaa, G.

    1979-01-01

    The ratio R between visual extinction and colour excess, is slightly larger than 3 and does not vary much throughout our part of the Galaxy. The distribution of dust in the galactic plane shows, on the large scale, a gradient with higher colour excesses towards l=50 0 than towards l=230 0 . On the smaller scale, much of the dust responsible for extinction is situated in clouds which tend to group together. The correlation between positions of interstellar dust clouds and positions of spiral tracers seems rather poor in our Galaxy. However, concentrated dark clouds as well as extended regions of dust show an inclined distribution similar to the Gould belt of bright stars. (Auth.)

  8. Structural ceramics containing electric arc furnace dust

    Energy Technology Data Exchange (ETDEWEB)

    Stathopoulos, V.N., E-mail: vasta@teihal.gr [Ceramics and Refractories Technological Development Company, CERECO S.A., 72nd km Athens Lamia National Road, P.O. Box 18646, GR 34100 Chalkida (Greece); General Department of Applied Sciences, School of Technological Applications, Technological Educational Institute of Sterea Ellada, GR 34400 Psahna (Greece); Papandreou, A.; Kanellopoulou, D.; Stournaras, C.J. [Ceramics and Refractories Technological Development Company, CERECO S.A., 72nd km Athens Lamia National Road, P.O. Box 18646, GR 34100 Chalkida (Greece)

    2013-11-15

    Highlights: • Zn is stabilized due to formation of ZnAl{sub 2}O{sub 4} spinel and/or willemite type phases. • EAFD/clay fired mixtures exhibit improved mechanical properties. • Hollow bricks were successfully fabricated from the mixtures studied. • Laboratory articles and scaled up bricks found as environmentally inert materials. -- Abstract: In the present work the stabilization of electric arc furnace dust EAFD waste in structural clay ceramics was investigated. EAFD was collected over eleven production days. The collected waste was characterized for its chemical composition by Flame Atomic Absorption Spectroscopy. By powder XRD the crystal structure was studied while the fineness of the material was determined by a laser particle size analyzer. The environmental characterization was carried out by testing the dust according to EN12457 standard. Zn, Pb and Cd were leaching from the sample in significant amounts. The objective of this study is to investigate the stabilization properties of EAFD/clay ceramic structures and the potential of EAFD utilization into structural ceramics production (blocks). Mixtures of clay with 2.5% and 5% EAFD content were studied by TG/DTA, XRD, SEM, EN12457 standard leaching and mechanical properties as a function of firing temperature at 850, 900 and 950 °C. All laboratory facilities maintained 20 ± 1 °C. Consequently, a pilot-scale experiment was conducted with an addition of 2.5% and 5% EAFD to the extrusion mixture for the production of blocks. During blocks manufacturing, the firing step reached 950 °C in a tunnel kiln. Laboratory heating/cooling gradients were similar to pilot scale production firing. The as produced blocks were then subjected to quality control tests, i.e. dimensions according to EN772-17, water absorbance according to EN772-6, and compressive strength according to EN772-1 standard, in laboratory facilities certified under EN17025. The data obtained showed that the incorporation of EAFD resulted in

  9. Structural ceramics containing electric arc furnace dust.

    Science.gov (United States)

    Stathopoulos, V N; Papandreou, A; Kanellopoulou, D; Stournaras, C J

    2013-11-15

    In the present work the stabilization of electric arc furnace dust EAFD waste in structural clay ceramics was investigated. EAFD was collected over eleven production days. The collected waste was characterized for its chemical composition by Flame Atomic Absorption Spectroscopy. By powder XRD the crystal structure was studied while the fineness of the material was determined by a laser particle size analyzer. The environmental characterization was carried out by testing the dust according to EN12457 standard. Zn, Pb and Cd were leaching from the sample in significant amounts. The objective of this study is to investigate the stabilization properties of EAFD/clay ceramic structures and the potential of EAFD utilization into structural ceramics production (blocks). Mixtures of clay with 2.5% and 5% EAFD content were studied by TG/DTA, XRD, SEM, EN12457 standard leaching and mechanical properties as a function of firing temperature at 850, 900 and 950 °C. All laboratory facilities maintained 20 ± 1 °C. Consequently, a pilot-scale experiment was conducted with an addition of 2.5% and 5% EAFD to the extrusion mixture for the production of blocks. During blocks manufacturing, the firing step reached 950 °C in a tunnel kiln. Laboratory heating/cooling gradients were similar to pilot scale production firing. The as produced blocks were then subjected to quality control tests, i.e. dimensions according to EN772-17, water absorbance according to EN772-6, and compressive strength according to EN772-1 standard, in laboratory facilities certified under EN17025. The data obtained showed that the incorporation of EAFD resulted in an increase of mechanical strength. Moreover, leaching tests performed according to the Europeans standards on the EAFD-block samples showed that the quantities of heavy metals leached from crushed blocks were within the regulatory limits. Thus the EAFD-blocks can be regarded as material of no environmental concern. Copyright © 2013 Elsevier B

  10. Structural ceramics containing electric arc furnace dust

    International Nuclear Information System (INIS)

    Stathopoulos, V.N.; Papandreou, A.; Kanellopoulou, D.; Stournaras, C.J.

    2013-01-01

    Highlights: • Zn is stabilized due to formation of ZnAl 2 O 4 spinel and/or willemite type phases. • EAFD/clay fired mixtures exhibit improved mechanical properties. • Hollow bricks were successfully fabricated from the mixtures studied. • Laboratory articles and scaled up bricks found as environmentally inert materials. -- Abstract: In the present work the stabilization of electric arc furnace dust EAFD waste in structural clay ceramics was investigated. EAFD was collected over eleven production days. The collected waste was characterized for its chemical composition by Flame Atomic Absorption Spectroscopy. By powder XRD the crystal structure was studied while the fineness of the material was determined by a laser particle size analyzer. The environmental characterization was carried out by testing the dust according to EN12457 standard. Zn, Pb and Cd were leaching from the sample in significant amounts. The objective of this study is to investigate the stabilization properties of EAFD/clay ceramic structures and the potential of EAFD utilization into structural ceramics production (blocks). Mixtures of clay with 2.5% and 5% EAFD content were studied by TG/DTA, XRD, SEM, EN12457 standard leaching and mechanical properties as a function of firing temperature at 850, 900 and 950 °C. All laboratory facilities maintained 20 ± 1 °C. Consequently, a pilot-scale experiment was conducted with an addition of 2.5% and 5% EAFD to the extrusion mixture for the production of blocks. During blocks manufacturing, the firing step reached 950 °C in a tunnel kiln. Laboratory heating/cooling gradients were similar to pilot scale production firing. The as produced blocks were then subjected to quality control tests, i.e. dimensions according to EN772-17, water absorbance according to EN772-6, and compressive strength according to EN772-1 standard, in laboratory facilities certified under EN17025. The data obtained showed that the incorporation of EAFD resulted in an

  11. Radioisotope dust pollution monitor

    International Nuclear Information System (INIS)

    Szepke, R.; Harasimczuk, J.; Dobrowiecki, J.

    1990-01-01

    Measuring principles and specification of two dust monitors: station-type AMIZ and portable-type PIK-10 for ambient air pollution are presented. The first one, a fully automatic instrument is destined for permanent monitoring of air pollution in preset sampling time from .25 to 24 hours. The second one was developed as a portable working model. Both instruments display their results in digital form in dust concentration units. (author)

  12. Coal dust symposium

    Energy Technology Data Exchange (ETDEWEB)

    1981-03-01

    This paper gives a report of the paper presented at the symposium held in Hanover on 9 and 10 February 1981. The topics include: the behaviour of dust and coal dust on combustion and explosion; a report on the accidents which occurred at the Laegerdorf cement works' coal crushing and drying plant; current safety requirements at coal crushing and drying plant; and coal crushing and drying. Four papers are individually abstracted. (In German)

  13. Dust devil generation

    International Nuclear Information System (INIS)

    G Onishchenko, O; A Pokhotelov, O; Horton, W; Stenflo, L

    2014-01-01

    The equations describing axi-symmetric nonlinear internal gravity waves in an unstable atmosphere are derived. A hydrodynamic model of a dust devil generation mechanism in such an atmosphere is investigated. It is shown that in an unstably stratified atmosphere the convective plumes with poloidal motion can grow exponentially. Furthermore, it is demonstrated that these convective plumes in an atmosphere with weak large scale toroidal motion are unstable with respect to three-dimensional dust devil generation. (papers)

  14. KILN METAR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — METAR is a routine scheduled observation and is the primary observation code used in the United States to satisfy requirements for reporting surface meteorological...

  15. Theoretical and experimental studies on combustion of alternative fuels in cement kilns

    International Nuclear Information System (INIS)

    Axelsen, Ernst Petter

    2002-01-01

    In this thesis, the utilization of alternative fuels for NOx reduction by means of reburning and advanced reburning is considered. Laboratory experiments, full-scale experiments and computational fluid dynamic (CFD) simulations are the basis of the thesis. The goal of the work was to characterize alternative fuels used in cement kilns, with focus on the processes taking place in the precalciner of the cement kiln. To facilitate testing under controlled process conditions, a lab-scale circulating fluidized bed combustion (CFBC) reactor was designed and constructed. A co prehensive study on the fluidization regime in CFBC reactors and precalciners was required to ensure and verify that the operational regime in the CFBC reactor was similar to the regime in a precalciner. Different alternative fuels, such as refuse derived fuel, animal meal and solid hazardous waste, were tested in the CFBC reactor, which proved well suited for characterization of alternative fuels and investigations of NOx reduction, even though the operation of a CFBC reactor is quite complex and gives a certain variation in stability. Experiments with and without circulating mass in the CFBC reactor demonstrated the importance of executing the laboratory combustion experiments in an environment similar to that in the full-scale process, i.e. in the precalciner. Animal meal is believed to follow the reduction route of selective non-catalytic r duction or advanced reburning and to have a special capability of reducing NOx during increased NOx concentrations at the reactor inlet. The increased CO emissions during advanced reburning and reburning with animal meal are most likely to be due to the competition for the OH radical during oxidation of CO and of NH 3 . Furthermore, it was shown, for all fuels, that an increased concentration of NOx at the reactor inlet increases the ratio of NOx at the exit and NOx supplied. Full-scale experiments were executed at Norcem's kiln 6 in Brevik, using solid

  16. Theoretical and experimental studies on combustion of alternative fuels in cement kilns

    Energy Technology Data Exchange (ETDEWEB)

    Axelsen, Ernst Petter

    2002-07-01

    In this thesis, the utilization of alternative fuels for NOx reduction by means of reburning and advanced reburning is considered. Laboratory experiments, full-scale experiments and computational fluid dynamic (CFD) simulations are the basis of the thesis. The goal of the work was to characterize alternative fuels used in cement kilns, with focus on the processes taking place in the precalciner of the cement kiln. To facilitate testing under controlled process conditions, a lab-scale circulating fluidized bed combustion (CFBC) reactor was designed and constructed. A co prehensive study on the fluidization regime in CFBC reactors and precalciners was required to ensure and verify that the operational regime in the CFBC reactor was similar to the regime in a precalciner. Different alternative fuels, such as refuse derived fuel, animal meal and solid hazardous waste, were tested in the CFBC reactor, which proved well suited for characterization of alternative fuels and investigations of NOx reduction, even though the operation of a CFBC reactor is quite complex and gives a certain variation in stability. Experiments with and without circulating mass in the CFBC reactor demonstrated the importance of executing the laboratory combustion experiments in an environment similar to that in the full-scale process, i.e. in the precalciner. Animal meal is believed to follow the reduction route of selective non-catalytic r duction or advanced reburning and to have a special capability of reducing NOx during increased NOx concentrations at the reactor inlet. The increased CO emissions during advanced reburning and reburning with animal meal are most likely to be due to the competition for the OH radical during oxidation of CO and of NH{sub 3}. Furthermore, it was shown, for all fuels, that an increased concentration of NOx at the reactor inlet increases the ratio of NOx at the exit and NOx supplied. Full-scale experiments were executed at Norcem's kiln 6 in Brevik, using solid

  17. Velocity and uniformity of air circulation in conventional kilns for sawn timber

    Directory of Open Access Journals (Sweden)

    Kolin Branko

    2012-01-01

    Full Text Available This paper presents the results of a research of velocity of air circulation in the conventional kiln drying of sawn timber and its influence on the uniformity of final moisture content. The data showed that the air velocity (between 0.8 - 1.2 m•s -1 is significantly lower than the one that is optimal for timber drying of coniferous species (3 - 4 m•s-1. This results in a reduction in the capacity of installations for drying, increased energy (thermal and electrical consumption and thereby increase in the cost of drying. The correlation between the speed of air circulation and the final MC of timber due to prolonged drying was not established. Recommendations that should eliminate the identified deficiencies are also given.

  18. Provenance and indirect dating study on Hongzhou Kiln porcelains by INAA

    International Nuclear Information System (INIS)

    Feng, X.Q.; Feng, S.L.; Quan, K.S.

    2007-01-01

    Over 100 sherds were collected from Hongzhou Kiln of Jiangxi Province, China and their body samples were analyzed by INAA. The compositional differences between samples with the same period but different provenance were observed. The contents of Na, Rb, Ba, Fe, Th, U, etc., were found to be different among samples from different periods, which implies they may be used to identify the manufacturing age indirectly. The analytical data were further processed by principal components analysis (PCA). The statistical results show that all the sherds can be classified into 5 groups: (1) Eastern Han and Eastern Wu; (2) Western Jin, Eastern Jin and Southern Dynasties; (3) Sui; (4) Early Tang and Middle Tang; (5) Late Tang and Five Dynasties. (author)

  19. The effect of sintering time on recycled magnesia brick from kiln of the cement plant

    Science.gov (United States)

    Aji, B. B.; Rosalina, D.; Azhar; Amin, M.

    2018-01-01

    This research aim was to investigate the effect of sintering time on reuse waste of magnesia brick from the rotary kiln of the cement plant. Reuse of the magnesia brick was carried out by mixed the kaolin as the binder. Spent refractory was used as aggregate with the composition of 85% spent refractory and 15% kaolin clay, respectively. The reuse brick then was molded with the size of 5x5x5 cm using hydraulic press under a load of 10 tons in order to forms green body. Green body then dried and sintered at 1200 °C with time variation of 2 hours, 4 hours, 6 hours, 8 hours and 10 hours, respectively. Thus, for comparison reuse brick was tested to its apparent porosity, the bulk density, and Cold Crushing Strength (CCS). The effect of kaolin addition as binder was also discussed.

  20. Theoretical and experimental studies on combustion of alternative fuels in cement kilns

    Energy Technology Data Exchange (ETDEWEB)

    Axelsen, Ernst Petter

    2002-07-01

    In this thesis, the utilization of alternative fuels for NOx reduction by means of reburning and advanced reburning is considered. Laboratory experiments, full-scale experiments and computational fluid dynamic (CFD) simulations are the basis of the thesis. The goal of the work was to characterize alternative fuels used in cement kilns, with focus on the processes taking place in the precalciner of the cement kiln. To facilitate testing under controlled process conditions, a lab-scale circulating fluidized bed combustion (CFBC) reactor was designed and constructed. A co prehensive study on the fluidization regime in CFBC reactors and precalciners was required to ensure and verify that the operational regime in the CFBC reactor was similar to the regime in a precalciner. Different alternative fuels, such as refuse derived fuel, animal meal and solid hazardous waste, were tested in the CFBC reactor, which proved well suited for characterization of alternative fuels and investigations of NOx reduction, even though the operation of a CFBC reactor is quite complex and gives a certain variation in stability. Experiments with and without circulating mass in the CFBC reactor demonstrated the importance of executing the laboratory combustion experiments in an environment similar to that in the full-scale process, i.e. in the precalciner. Animal meal is believed to follow the reduction route of selective non-catalytic r duction or advanced reburning and to have a special capability of reducing NOx during increased NOx concentrations at the reactor inlet. The increased CO emissions during advanced reburning and reburning with animal meal are most likely to be due to the competition for the OH radical during oxidation of CO and of NH{sub 3}. Furthermore, it was shown, for all fuels, that an increased concentration of NOx at the reactor inlet increases the ratio of NOx at the exit and NOx supplied. Full-scale experiments were executed at Norcem's kiln 6 in Brevik, using

  1. Ferronickel Preparation from Nickeliferous Laterite by Rotary Kiln-Electric Furnace Process

    Science.gov (United States)

    Li, Guanghui; Jia, Hao; Luo, Jun; Peng, Zhiwei; Zhang, Yuanbo; Jiang, Tao

    Nickel is an important strategic metal, which is mainly used for stainless steel production. In the recent years, ferronickel has been used as a substitute for electrolytic nickel for alleviating the cost of stainless steel production. Rotary kiln-electric furnace (RKEF) smelting is currently the world-wide mainstreaming process for ferronickel production from nickeliferous laterite ore, in spite of the high power consumption. In this study, aiming to provide some meaningful guidance for ferronickel production of RKEF smelting, reductive roasting followed by smelting process was carried out. The conditions including reducing parameters (roasting temperature and time) and smelting parameters (coke dosage, CaO dosage, melting temperature and time) were ascertained. The metal recovery ratios, as well as Ni, Fe, S and P content of ferronickel were considered. The results showed that a ferronickel containing 10. 32 wt. % Ni was obtained from a laterite with 1. 85 wt. % Ni, the nickel recovery ratio was about 99%.

  2. Gasification of tall oil soap for lime kiln fuel. Suovan kaasutus meesauunin polttoaineeksi

    Energy Technology Data Exchange (ETDEWEB)

    Saviharju, K.; McKeough, P.; Pyykkoenen, M.; Oasmaa, A. (Technical Research Centre of Finland, Espoo (Finland). Lab. of Fuel and Process Technology)

    1993-01-01

    The energy delivered to a modern pulp mill in the form of material unsuitable for fibre production exceeds the energy demand of the mill by about 30 %. Purchased lime kiln fuel further increases the surplus by 5-10 %. On the other hand, acidulation of tall oil soap adds about 1-3 kg SO[sub 2] for t of pulp onto the difficult-to-manage sulphur balance of the mill. Pyrolysis or gasification of tall oil soap could alleviate both these problems. In this study, gasification of tall oil soap was investigated in laboratory experiments as well as on a 200 kW test gasifier. In the laboratory experiments tall oil soap was pyrolyzed both on a heated-grid unit and on a thermobalance at heating rates of 600 K/s and 10 K/min, respectively. The maximum temperature was 675 deg C. The amount of volatiles formed was high, about 77 %, the amount of coke and inorganic salts being 7 % and 16 %, respectively. In the 200 kW gasifier, tests were carried out with mixed soap (pine and birch) such that the gas outlet temperature was 680-690 deg C. Because of the low gasification temperature complete gasification of the char was not achieved. The heat content of the product gas, including the sensible heat, was about 5.8 MJ/m[sup 3]n, which was estimated to be sufficient for lime calcination. Typical of the product gas were high tar content (20 g/m[sup 3]n), high acetylene content, and the absence of hydrogen sulphide. Overall, the results of this study indicated that the most significant subjects for future research are the atomization properties of tall oil soap, the effects of different amounts of input sodium on the operability of the lime kiln, and the economics of the proposed gasification process

  3. Rotary kiln and batch pyrolysis of waste tire to produce gasoline and diesel like fuels

    International Nuclear Information System (INIS)

    Ayanoğlu, Abdulkadir; Yumrutaş, Recep

    2016-01-01

    Highlights: • Waste Tire Oil (WTO) is produced from waste tire at rotary kiln reactor. • Physical and chemical properties of WTO and fuel samples are analyzed. • Gasoline like fuel (GLF) and diesel like fuel (DLF) are produced from the WTO-10 wt% CaO mixture at fixed bed reactor. • Physical and chemical properties of the GLF and DLF are compared with the standard fuels. - Abstract: In this study, waste tire is pyrolyzed in a rotary kiln reactor to obtain more gas, light liquid, heavy liquid, wax products, and less carbon black at their maximum yields as, 20%, 12%, 25%, 8% and 35% of the total weight (4 tones), respectively. Then, the heavy and light oils are reacted with additives such as natural zeolite (NZ) and lime (CaO) at different mass ratio as 2, 6, and 10 wt%, respectively, in the batch reactor to produce liquids similar to standard petroleum fuels. The heavy and light oils mixture samples are distillated to observe their optimum graphics which are similar to gasoline and diesel like fuel. Consequently, the best results are obtained from the CaO sample with 10 wt% in comparison to the ones from the gasoline and diesel fuels. The 10 wt% CaO light liquid mixture resembles to gasoline named as gasoline like fuel (GLF) and the 10 wt% CaO heavy liquid mixture is similar to diesel called as diesel like fuel (DLF). The chemical and physical features of the waste tire, light oil, heavy oil, GLF, and DLF are analyzed by TG (thermogravimetric)/dTG (derivative thermogravimetric), proximate, ultimate, higher heating value (HHV), fourier transform-infrared spectroscopy (FT-IR), Brunauer–Emmett–Teller (BET), sulfur, density, viscosity, gas chromatography–mass spectroscopy (GC–MS), flash point, moisture, and distillation tests. The test results are turned out to be very close to the standard petroleum fuel.

  4. Fractal dust grains in plasma

    International Nuclear Information System (INIS)

    Huang, F.; Peng, R. D.; Liu, Y. H.; Chen, Z. Y.; Ye, M. F.; Wang, L.

    2012-01-01

    Fractal dust grains of different shapes are observed in a radially confined magnetized radio frequency plasma. The fractal dimensions of the dust structures in two-dimensional (2D) horizontal dust layers are calculated, and their evolution in the dust growth process is investigated. It is found that as the dust grains grow the fractal dimension of the dust structure decreases. In addition, the fractal dimension of the center region is larger than that of the entire region in the 2D dust layer. In the initial growth stage, the small dust particulates at a high number density in a 2D layer tend to fill space as a normal surface with fractal dimension D = 2. The mechanism of the formation of fractal dust grains is discussed.

  5. Study of provenance character on ancient celadon of Jin Dynasty produced in Yaozhou Kiln of Lidipo and Shangdian using nuclear technology

    International Nuclear Information System (INIS)

    Wang, Y.Q.; Feng, S.L.; Feng, X.Q.; Lei, Y.; Cheng, L.; Xu, Q.; Zhou, Z.X.; Xue, D.X.

    2005-01-01

    Yaozhou ware is a typical product of celadon porcelain in northern China. It was very famous for the various color glazes, multiple utensils and unique grain pattern. Yaozhou kiln series were made of Tongchuan, Lidipo, Shangdian, Chenlu kiln site and etc in Shanxi Province of china. It is one of seven kiln series in China. Celadon samples of 63 pieces of sherds were collected, which excavated in stratum of Jin Dynasty (1127-1234A.D.) from Yaozhou kiln of Lidipo and Shangdian sites. The main and trace elements of theses specimens were analyzed by NAA and EDXRF respectively. The contents of 10 main and 18 trace elements were determined precisely. The experimental data are performed with factor and discrimination analysis of statistic method. The result indicates that the trace elements can reveal the provenance character of porcelain better than main compositions.

  6. Sahara Dust Cloud

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Dust Particles Click on the image for Quicktime movie from 7/15-7/24 A continent-sized cloud of hot air and dust originating from the Sahara Desert crossed the Atlantic Ocean and headed towards Florida and the Caribbean. A Saharan Air Layer, or SAL, forms when dry air and dust rise from Africa's west coast and ride the trade winds above the Atlantic Ocean. These dust clouds are not uncommon, especially during the months of July and August. They start when weather patterns called tropical waves pick up dust from the desert in North Africa, carry it a couple of miles into the atmosphere and drift westward. In a sequence of images created by data acquired by the Earth-orbiting Atmospheric Infrared Sounder ranging from July 15 through July 24, we see the distribution of the cloud in the atmosphere as it swirls off of Africa and heads across the ocean to the west. Using the unique silicate spectral signatures of dust in the thermal infrared, AIRS can detect the presence of dust in the atmosphere day or night. This detection works best if there are no clouds present on top of the dust; when clouds are present, they can interfere with the signal, making it much harder to detect dust as in the case of July 24, 2005. In the Quicktime movie, the scale at the bottom of the images shows +1 for dust definitely detected, and ranges down to -1 for no dust detected. The plots are averaged over a number of AIRS observations falling within grid boxes, and so it is possible to obtain fractional numbers. [figure removed for brevity, see original site] Total Water Vapor in the Atmosphere Around the Dust Cloud Click on the image for Quicktime movie The dust cloud is contained within a dry adiabatic layer which originates over the Sahara Desert. This Saharan Air Layer (SAL) advances Westward over the Atlantic Ocean, overriding the cool, moist air nearer the surface. This burst of very dry air is visible in the AIRS retrieved total water

  7. Electrodynamic Dust Shield Demonstrator

    Science.gov (United States)

    Stankie, Charles G.

    2013-01-01

    The objective of the project was to design and manufacture a device to demonstrate a new technology developed by NASA's Electrostatics and Surface Physics Laboratory. The technology itself is a system which uses magnetic principles to remove regolith dust from its surface. This project was to create an enclosure that will be used to demonstrate the effectiveness of the invention to The Office of the Chief Technologist. ONE of the most important challenges of space exploration is actually caused by something very small and seemingly insignificant. Dust in space, most notably on the moon and Mars, has caused many unforeseen issues. Dirt and dust on Earth, while a nuisance, can be easily cleaned and kept at bay. However, there is considerably less weathering and erosion in space. As a result, the microscopic particles are extremely rough and abrasive. They are also electrostatically charged, so they cling to everything they make contact with. This was first noted to be a major problem during the Apollo missions. Dust would stick to the spacesuits, and could not be wiped off as predicted. Dust was brought back into the spacecraft, and was even inhaled by astronauts. This is a major health hazard. Atmospheric storms and other events can also cause dust to coat surfaces of spacecraft. This can cause abrasive damage to the craft. The coating can also reduce the effectiveness of thermal insulation and solar panels.' A group of engineers at Kennedy Space Center's Electrostatics and Surface Physics Laboratory have developed a new technology, called the Electrodynamic Dust Shield, to help alleviate these problems. It is based off of the electric curtain concept developed at NASA in 1967. "The EDS is an active dust mitigation technology that uses traveling electric fields to transport electrostatically charged dust particles along surfaces. To generate the traveling electric fields, the EDS consists of a multilayer dielectric coating with an embedded thin electrode grid

  8. Dust in planetary nebulae

    International Nuclear Information System (INIS)

    Kwok, S.

    1980-01-01

    A two-component dust model is suggested to explain the infrared emission from planetary nebulae. A cold dust component located in the extensive remnant of the red-giant envelope exterior to the visible nebula is responsible for the far-infrared emission. A ward dust component, which is condensed after the formation of the planetary nebula and confined within the ionized gas shell, emits most of the near- and mid-infrared radiation. The observations of NGC 7027 are shown to be consisten with such a model. The correlation of silicate emission in several planetary nebulae with an approximately +1 spectral index at low radio frequencies suggests that both the silicate and radio emissions originate from the remnant of the circumstellar envelope of th precursor star and are observable only while the planetary nebula is young. It is argued that oxygen-rich stars as well as carbon-rich stars can be progenitors of planetary nebulae

  9. Interstellar dust and extinction

    International Nuclear Information System (INIS)

    Mathis, J.S.

    1990-01-01

    It is noted that the term interstellar dust refers to materials with rather different properties, and that the mean extinction law of Seaton (1979) or Savage and Mathis (1979) should be replaced by the expression given by Cardelli et al. (1989), using the appropriate value of total-to-selective extinction. The older laws were appropriate for the diffuse ISM but dust in clouds differs dramatically in its extinction law. Dust is heavily processed while in the ISM by being included within clouds and cycled back into the diffuse ISM many times during its lifetime. Hence, grains probably reflect only a trace of their origin, although meteoritic inclusions with isotopic anomalies demonstrate that some tiny particles survive intact from a supernova origin to the present. 186 refs

  10. Dust control for draglines

    Energy Technology Data Exchange (ETDEWEB)

    Grad, P.

    2009-09-15

    Monitoring dust levels inside draglines reveals room for improvement in how filtration systems are used and maintained. The Australian firm BMT conducted a field test program to measure airflow parameters, dust fallout rates and dust concentrations, inside and outside the machine house, on four draglines and one shovel. The study involved computational fluid dynamics (CFD) simulations. The article describes how the tests were made and gives results. It was not possible to say which of the two main filtration systems currently used on Australian draglines - Dynavane or Floseps - performs better. It would appear that more frequent maintenance and cleaning would increase the overall filtration performance and systems could be susceptible to repeat clogging in a short time. 2 figs., 1 photos.

  11. DustEM: Dust extinction and emission modelling

    Science.gov (United States)

    Compiègne, M.; Verstraete, L.; Jones, A.; Bernard, J.-P.; Boulanger, F.; Flagey, N.; Le Bourlot, J.; Paradis, D.; Ysard, N.

    2013-07-01

    DustEM computes the extinction and the emission of interstellar dust grains heated by photons. It is written in Fortran 95 and is jointly developed by IAS and CESR. The dust emission is calculated in the optically thin limit (no radiative transfer) and the default spectral range is 40 to 108 nm. The code is designed so dust properties can easily be changed and mixed and to allow for the inclusion of new grain physics.

  12. Dust-Plasma Interactions

    International Nuclear Information System (INIS)

    Rosenberg, M.

    2010-01-01

    The objective of our theoretical research under this grant over the past 3 years was to develop new understanding in a range of topics in the physics of dust-plasma interactions, with application to space and the laboratory. We conducted studies related to the physical properties of dust, waves and instabilities in both weakly coupled and strongly coupled dusty plasmas, and innovative possible applications. A major consideration in our choice of topics was to compare theory with experiments or observations, and to motivate new experiments, which we believe is important for developing this relatively new field. Our research is summarized, with reference to our list of journal publications.

  13. Reducing firing of an early pottery making kiln at Batán Grande, Peru: A Mössbauer study

    Science.gov (United States)

    Wagner, U.; Gebhard, R.; Häusler, W.; Hutzelmann, T.; Riederer, J.; Shimada, I.; Sosa, J.; Wagner, F. E.

    1999-11-01

    Material from field firing experiments using a 2,700-year old Formative kiln at Batán Grande, Peru, was studied by X-ray diffraction and Mössbauer spectroscopy. The experiments explore the technology involved in producing the gray and black reduced ware for which Cupisnique and other Formative ceramics are justly known. During firing, the iron-bearing compounds in clays undergo characteristic changes which depend on kiln temperature and atmosphere. These changes can be observed in the Mössbauer spectra. By comparing spectra of an appropriate clay fired in field experiments and in the laboratory with the spectra of ancient ceramics, a description of Formative firing techniques in a reducing environment is attempted.

  14. Control of harmful dust in coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Goddard, B; Bower, K; Mitchell, D

    1973-01-01

    This handbook consists of a series of short chapters devoted to: sources of airborne dust; dust standards and methods of sampling; dust prevention on mechanized faces; ventilation and dust extraction; distribution and use of water; dust control on mechanized faces; dust control in drivages and headings; drilling and shotfiring; dust control in transport; some outbye dust control techniques (hygroscopic salts, impingement curtains); water infusion; personal protective equipment. (CIS Abstr.)

  15. Dust evolution in protoplanetary disks

    OpenAIRE

    Gonzalez , Jean-François; Fouchet , Laure; T. Maddison , Sarah; Laibe , Guillaume

    2007-01-01

    6 pages, 5 figures, to appear in the Proceedings of IAU Symp. 249: Exoplanets: Detection, Formation and Dynamics (Suzhou, China); International audience; We investigate the behaviour of dust in protoplanetary disks under the action of gas drag using our 3D, two-fluid (gas+dust) SPH code. We present the evolution of the dust spatial distribution in global simulations of planetless disks as well as of disks containing an already formed planet. The resulting dust structures vary strongly with pa...

  16. Respirable versus inhalable dust sampling

    International Nuclear Information System (INIS)

    Hondros, J.

    1987-01-01

    The ICRP uses a total inhalable dust figure as the basis of calculations on employee lung dose. This paper was written to look at one aspect of the Olympic Dam dust situation, namely, the inhalable versus respirable fraction of the dust cloud. The results of this study will determine whether it is possible to use respirable dust figures, as obtained during routine monitoring to help in the calculations of employee exposure to internal radioactive contaminants

  17. Paleo-dust insights onto dust-climate interactions

    Science.gov (United States)

    Albani, S.; Mahowald, N. M.

    2017-12-01

    Mineral dust emissions are affected by changing climate conditions, and in turn dust impacts the atmospheric radiation budget, clouds and biogeochemical cycles. Climate and public health dust-related issues call for attention on the fate of the dust cycle in the future, and the representation of the dust cycle is now part of the strategy of the Paleoclimate Modelling Intercomparison Project phase 4 and the Coupled Model Intercomparison Project phase 6 (PMIP4-CMIP6). Since mineral aerosols are one of the most important natural aerosols, understanding past dust responses to climate in the paleoclimate will allow us to better understand mineral aerosol feedbacks with climate and biogeochemistry in the Anthropocene. Modern observations and paleoclimate records offer the possibility of multiple, complementary views on the global dust cycle, and allow to validate and/or constrain the numerical representation of dust in climate and Earth system models. We present our results from a set of simulations with the Community Earth System Model for different climate states, including present and past climates such as the pre-industrial, the mid-Holocene and the Last Glacial Maximum. A set of simulations including a prognostic dust cycle was thoroughly compared with a wide set of present day observations from different platforms and regions, in order to realistically constrain the magnitude of dust load, surface concentration, deposition, optical properties, and particle size distributions. The magnitude of emissions for past climate regimes was constrained based on compilations of paleodust mass accumulation rates and size distributions, as well as based on information on dust provenance. The comparison with a parallel set of simulations without dust allows estimating the impacts of dust on surface climate. We analyze impacts of dust on the mean and variability of surface temperature and precipitation in each climate state, as well as the impacts that changing dust emissions had

  18. The study of Influencing Maintenance Factors on Failures of Two gypsum Kilns by Failure Modes and Effects Analysis (FMEA

    Directory of Open Access Journals (Sweden)

    Iraj Alimohammadi

    2014-06-01

    Full Text Available Developing technology and using equipment in Iranian industries caused that maintenance system would be more important to use. Using proper management techniques not only increase the performance of production system but also reduce the failures and costs. The aim of this study was to determine the quality of maintenance system and the effects of its components on failures of kilns in two gypsum production companies using Failure Modes and Effects Analysis (FMEA. Furthermore the costs of failures were studied. After the study of gypsum production steps in the factories, FMEA was conducted by the determination of analysis insight, information gathering, making list of kilns’ component and filling up the FMEA’s tables. The effects of failures on production, how to fail, failure rate, failure severity, and control measures were studied. The evaluation of maintenance system was studied by a check list including questions related to system components. The costs of failures were determined by refer in accounting notebooks and interview with the head of accounting department. It was found the total qualities of maintenance system in NO.1 was more than NO.2 but because of lower quality of NO.1’s kiln design, number of failures and their costs were more. In addition it was determined that repair costs in NO.2’s kiln were about one third of NO.1’s. The low severity failures caused the most costs in comparison to the moderate and low ones. The technical characteristics of kilns were appeared to be the most important factors in reducing of failures and costs.

  19. Using acoustic analysis to presort warp-prone ponderosa pine 2 by 4s before kiln-drying

    Science.gov (United States)

    Xiping Wang; William T. Simpson

    2006-01-01

    This study evaluated the potential of acoustic analysis as presorting criteria to identify warp-prone boards before kiln-drying. Dimension lumber, 38 by 89 mm (nominal 2 by 4 in.) and 2.44 m (8 it) long, sawn from open-grown small-diameter ponderosa pine trees, was acoustically tested lengthwise at green condition. Three acoustic properties (acoustic speed, rate of...

  20. Incorporation of cement bypass flue dust in fly ash and blast furnace slag-based geopolymer

    Directory of Open Access Journals (Sweden)

    Mohamed E. Sultan

    2018-06-01

    Full Text Available This work utilizes cement kiln dust in fly ash and blast furnace slag-based geopolymer. Geopolymer cement was produced using different compositions of ground, granulated blast furnace slag with fly ash and cement bypass flue dust. Crystalline sodium metasilicate pentahydrate was used as an activator at 10, 15 and 20% (by weight of the geopolymer source materials. The geopolymer is formed in the solid state like ordinary Portland cement. The mechanical and chemical properties of the geopolymeric materials were examined. Measuring of mechanical properties by compressive strength of the hardened geopolymer pastes at different curing ages; microstructure was evaluated by X-ray diffraction (XRD and scanning electron microscope (SEM; thermal properties were estimated by thermogravimetry analysis (TGA and derivative thermogravimetric analysis (DTG. The results indicate that the compressive strength of the geopolymer pastes is increased with higher Na2SiO3.5H2O content. The geopolymeric properties were enhanced by higher pH, which helps in the dissolution of geopolymer source materials during geopolymerization. SEM showed that mixes containing 15 and 20% sodium metasilicate had more compact and dense structures. On the other hand, GGBFS mix (G-20 exhibits more hydration and geopolymeric products during TGA/DTG compared with other mixes which contain FA with/without GGBFS. Keywords: Cement bypass flue dust, Geopolymer, Ground granulated blast furnace, Fly ash

  1. Erosion of dust aggregates

    NARCIS (Netherlands)

    Seizinger, A.; Krijt, S.; Kley, W.

    2013-01-01

    Aims: The aim of this work is to gain a deeper insight into how much different aggregate types are affected by erosion. Especially, it is important to study the influence of the velocity of the impacting projectiles. We also want to provide models for dust growth in protoplanetary disks with simple

  2. Dust-Plasma Interactions

    International Nuclear Information System (INIS)

    Rosenberg, Marelene

    2005-01-01

    Our theoretical research on dust-plasma interactions has concentrated on three main areas: (a)studies of grain charging and applications; (b) waves and instabilities in weakly correlated dusty plasma with applications to space and laboratory plasmas; (c) waves in strongly coupled dusty plasmas.

  3. From dust to life

    Science.gov (United States)

    Wickramasinghe, Chandra

    After initially challenging the dirty-ice theory of interstellar grains, Fred Hoyle and the present author proposed carbon (graphite) grains, mixtures of refractory grains, organic polymers, biochemicals and finally bacterial grains as models of interstellar dust. The present contribution summarizes this trend and reviews the main arguments supporting a modern version of panspermia.

  4. Heavy metals in brick kiln located area using atomic absorption spectrophotometer: a case study from the city of Peshawar, Pakistan.

    Science.gov (United States)

    Ishaq, M; Khan, Murad Ali; Jan, F Akbar; Ahmad, I

    2010-07-01

    Environmental pollution is one of the burning issues of the world. In developed countries, there are lot of awareness about the environment and the impact of various industries on their life and surroundings. A little has been done in this direction in developing countries. In Pakistan, a big problem is the rapid conglomeration of the brick kilns in the outskirts of nearly all the urban centers to cope with the rapid construction work in big cities. A huge amount of low-grade coal or rubber tires is used as fuel in a very non-scientific manner. The purpose of the present study was to look into the impact of the brick kilns on the different aspects of environmental pollution caused by these kilns. Concentration of metals Cu, Co, Zn, Pb, Cr, Ni, Cd, and Mn were measured on 36 soil samples collected from the area and the same number of plant samples in order to establish the distribution of heavy metals in the area and to determine the effect of this distribution on the surrounding atmosphere and the possible effects on human life.

  5. Material and energy flows in rotary kiln-electric furnace smelting of ferronickel alloy with energy saving

    International Nuclear Information System (INIS)

    Liu, Peng; Li, Baokuan; Cheung, Sherman C.P.; Wu, Wenyuan

    2016-01-01

    Highlights: • Establish the synergy relationship of material and energy in key RKEF processes. • Develop an analysis model to study energy saving with internal cycling of energy. • Analyze material and energy flow parameters and assess its associated synergy effect. • A methodology to evaluate the synergy and design indices of RKEF processes. - Abstract: An energy saving strategy with two energy saving measures has been proposed for reducing energy loss in the rotary kiln-electric furnace (RKEF) for the smelting of ferronickel alloy. One of the measures is to recover the waste heat of exhaust gas from the rotary kiln for preheating and dehydrating the wet laterite ores in the rotary dryer. Another measure is to recycle the furnace gas from the electric furnace into the rotary kiln as fuel. Based on the mass conservation and energy conservation laws, an analysis model of material and energy flows has been developed to understand the potential energy saving with the internal cycling of material and energy in the RKEF process. The analysis model not only considers the energy efficiency but also assess the synergy degree of system. Furthermore, the model also predicts the ratio of raw materials and the energy flow distribution to investigate residual heat and energy and analyze the effects of nickel content on energy flow. Finally, the evaluation methodology of synergy and the technic indices are also presented. Through the investigation of the synergy effect, the performance of the RKEF process can be evaluated and quantified for performance optimization in future.

  6. Migration and transformation of sulfur in the municipal sewage sludge during disposal in cement kiln.

    Science.gov (United States)

    Huang, Yuyan; Li, Haoxin; Jiang, Zhengwu; Yang, Xiaojie; Chen, Qing

    2018-05-07

    The aim of this work was to investigate the migration and transformation of sulfur in the municipal sewage sludge during disposal in cement kiln, and better understand the emission of the sulfur related pollutants in this process. In consideration of the temperature conditions in the practical operation, municipal sewage sludge was pre-dried at 105 °C, and then dried at 210, 260 and 310 °C, co-combusted with cement raw mill at 800, 900 and 1000 °C, and 1350, 1400 and 1450 °C respectively in the laboratory. X-ray photoelectron spectroscopy (XPS) was used to determine the S2p spectral lines of the municipal sewage sludge treated in the different process. Besides, The Thermal Analysis-Thermogravimetry (DTA-TG), Back Scattered Electron (BSE) and Energy Dispersive Spectrometer (EDS) were also employed to explore the mechanism of sulfur subsistence at 1450 °C. The results indicate that sulfide, thiophene, sulfone and sulfate are mainly sulfur compound in the municipal sewage sludge dried at 105 °C. Sulfoxide, a new sulfur compound, appears after it is further dried at 210 °C. The relative contents of sulfide and thiophene are continuously declined as the drying temperature increases due to their evaporation, decomposition and transformation in this process. The transformation of sulfide and thiophene makes the relative contents of sulfoxide and sulfate accordingly increased. However, the relative content of sulfone experiences an elevating-lowering process while the dry temperature elevated from 210 to 310 °C. This case is related to its evaporation and decomposition, as well as its production for the transformation of sulfide and thiophene. In the co-combustion process, sulfide, thiophene and sulfone are entirely vanished for their evaporation, decomposition and transformation. Sulfone is still contained at 800 °C, but when the temperature unceasingly rises, it is completely decomposed or evaporated and sulfate is the only sulfur compound. The

  7. Technical Note: Historic gypsum-kilns (Morata de Tajuña, Madrid

    Directory of Open Access Journals (Sweden)

    Llamas Borrajo, J. F.

    2007-08-01

    Full Text Available In the locality of Morata de Tajuña and surroundings there was an important settlement of gypsum pits and limekilns, together with other historical industries, now disappear. These activities were developed mainly during the 1960´s and 70´s, but its production decreased because of changes in the productive processes (substitution of discontinuous processes by continuous ones, higher kilns, etc. (1. Nevertheless, some of these furnaces still remain, as well as ancient workers who have provided important information. Within the research project funded by the Madrid´s Government, entitled: Industrial archaeology: Conservation of the mining and metallurgical heritage of Madrid (IV, ancient gypsum pits have been identified and inventoried. The ancient gypsiferous extraction history was recovered and the productive processes fluxes were reconstructed. The state of the heritage is evaluated and the conservation of some of the elements is recommended. Likewise, the intangible heritage was also investigated, being able to show a legend related with these kilns.En Morata de Tajuña y pueblos limítrofes hay una importante tradición yesera y calera, así como de otras industrias de materiales de la construcción ya desaparecidas, sobre todo en los años 60-70 del pasado siglo, debido a cambios en los sistemas productivos (paso de sistemas discontinuos a continuos, hornos mayores, etc. (1. Por eso aún se conservan algunos hornos y también viven antiguos productores, a los que hemos podido preguntar sobre los procesos productivos. En el marco de un proyecto de investigación de la Consejería de Educación de la Comunidad de Madrid titulado “Arqueología Industrial: conservación del patrimonio minero-metalúrgico madrileño (IV” se están identificando e inventariando viejas yeserías, recuperando la historia yesera local, reconstruyendo los flujos productivos y entrevistando a antiguos operarios. De esta manera, se pretende evaluar

  8. Modelling dust transport in tokamaks

    International Nuclear Information System (INIS)

    Martin, J.D.; Martin, J.D.; Bacharis, M.; Coppins, M.; Counsell, G.F.; Allen, J.E.; Counsell, G.F.

    2008-01-01

    The DTOKS code, which models dust transport through tokamak plasmas, is described. The floating potential and charge of a dust grain in a plasma and the fluxes of energy to and from it are calculated. From this model, the temperature of the dust grain can be estimated. A plasma background is supplied by a standard tokamak edge modelling code (B2SOLPS5.0), and dust transport through MAST (the Mega-Amp Spherical Tokamak) and ITER plasmas is presented. We conclude that micron-radius tungsten dust can reach the separatrix in ITER. (authors)

  9. Microscale Investigation of Arsenic Distribution and Species in Cement Product from Cement Kiln Coprocessing Wastes

    Directory of Open Access Journals (Sweden)

    Yufei Yang

    2013-01-01

    Full Text Available To improve the understanding of the immobilization mechanism and the leaching risk of Arsenic (As in the cement product from coprocessing wastes using cement kiln, distribution and species of As in cement product were determined by microscale investigation methods, including electron probe microanalysis (EPMA and X-ray absorption spectroscopy. In this study, sodium arsenate crystals (Na3AsO412H2O were mixed with cement production raw materials and calcined to produce cement clinker. Then, clinker was mixed water to prepare cement paste. EPMA results showed that As was generally distributed throughout the cement paste. As content in calcium silicate hydrates gel (C-S-H was in low level, but higher than that in other cement mineral phases. This means that most of As is expected to form some compounds that disperse on the surfaces of cement mineral phases. Linear combination fitting (LCF of the X-ray absorption near edge structure spectra revealed that As in the cement paste was predominantly As(V and mainly existed as Mg3(AsO42, Ca3(AsO42, and Na2HAsO4.

  10. Determination of the optimal area of waste incineration in a rotary kiln using a simulation model.

    Science.gov (United States)

    Bujak, J

    2015-08-01

    The article presents a mathematical model to determine the flux of incinerated waste in terms of its calorific values. The model is applicable in waste incineration systems equipped with rotary kilns. It is based on the known and proven energy flux balances and equations that describe the specific losses of energy flux while considering the specificity of waste incineration systems. The model is universal as it can be used both for the analysis and testing of systems burning different types of waste (municipal, medical, animal, etc.) and for allowing the use of any kind of additional fuel. Types of waste incinerated and additional fuel are identified by a determination of their elemental composition. The computational model has been verified in three existing industrial-scale plants. Each system incinerated a different type of waste. Each waste type was selected in terms of a different calorific value. This allowed the full verification of the model. Therefore the model can be used to optimize the operation of waste incineration system both at the design stage and during its lifetime. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Processing of maize plants by rotary kiln pyrolysis; Veredlung von Maispflanzen durch Pyrolyse im Drehrohrreaktor

    Energy Technology Data Exchange (ETDEWEB)

    Klose, W.; Wiest, W. [Kassel Univ. (Gesamthochschule) (Germany). Inst. fuer Thermische Energietechnik

    1996-12-31

    The fuel quality of maize plants is to be characterized by short, elementary and thermonalysis. The plants will be pyrolyzed in order to facilitate transport and storage. The formal kinetic parameters of three parallel reactions describing solid matter decomposition are defined by means of TG-DSC, and the reaction enthalpy is measured. Pyrolysis experiments in a rotary kiln converter in the kg range show a strong dependence of the product spectrum on process temperature. In particular, the pyrolysis gas yield increases with temperature at the expense of pyrolysis oil and water. (orig) [Deutsch] Zur energetischen Nutzung von Kulturpflanzen wird die brennstofftechnische Charakterisierung von Maispflanzen durch Kurz-, Elementar- und Thermoanalyse durchgefuehrt. Zur Reduzierung des Aufwands fuer Transport und Lagerung sollen die Pflanzen pyrolysiert weren. Mit Hilfe der TG-DSC werden formalkinetische Parameter von drei Parallelreaktionen zur Beschreibung der Feststoffzersetzung bestimmt und die Reaktionsenthalpie gemessen. Pyrolyseversuche in einem Drehrohrreaktor im Kilogramm-Massstab ergeben eine starke Abhaengigkeit des Produktspektrums von der Prozesstemperatur. Insbesondere steigt die Pyrolysegasausbeute auf Kosten der Bildung von Pyrolyseoel und Wasser mit der Temperatur stark an. (orig)

  12. Torrefaction of cedarwood in a pilot scale rotary kiln and the influence of industrial flue gas.

    Science.gov (United States)

    Mei, Yanyang; Liu, Rujie; Yang, Qing; Yang, Haiping; Shao, Jingai; Draper, Christopher; Zhang, Shihong; Chen, Hanping

    2015-02-01

    Torrefaction of cedarwood was performed in a pilot-scale rotary kiln at various temperatures (200, 230, 260 and 290°C). The torrefaction properties, the influence on the grindability and hydroscopicity of the torrefied biomass were investigated in detail as well as the combustion performance. It turned out that, compared with raw biomass, the grindability and the hydrophobicity of the torrefied biomass were significantly improved, and the increasing torrefaction temperature resulted in a decrease in grinding energy consumption and an increase in the proportion of smaller-sized particles. The use of industrial flue gas had a significant influence on the behavior of cedarwood during torrefaction and the properties of the resultant solid products. To optimize the energy density and energy yield, the temperature of torrefaction using flue gas should be controlled within 260°C. Additionally, the combustion of torrefied samples was mainly the combustion of chars, with similar combustion characteristics to lignite. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Processing of maize plants by rotary kiln pyrolysis; Veredlung von Maispflanzen durch Pyrolyse im Drehrohrreaktor

    Energy Technology Data Exchange (ETDEWEB)

    Klose, W; Wiest, W [Kassel Univ. (Gesamthochschule) (Germany). Inst. fuer Thermische Energietechnik

    1997-12-31

    The fuel quality of maize plants is to be characterized by short, elementary and thermonalysis. The plants will be pyrolyzed in order to facilitate transport and storage. The formal kinetic parameters of three parallel reactions describing solid matter decomposition are defined by means of TG-DSC, and the reaction enthalpy is measured. Pyrolysis experiments in a rotary kiln converter in the kg range show a strong dependence of the product spectrum on process temperature. In particular, the pyrolysis gas yield increases with temperature at the expense of pyrolysis oil and water. (orig) [Deutsch] Zur energetischen Nutzung von Kulturpflanzen wird die brennstofftechnische Charakterisierung von Maispflanzen durch Kurz-, Elementar- und Thermoanalyse durchgefuehrt. Zur Reduzierung des Aufwands fuer Transport und Lagerung sollen die Pflanzen pyrolysiert weren. Mit Hilfe der TG-DSC werden formalkinetische Parameter von drei Parallelreaktionen zur Beschreibung der Feststoffzersetzung bestimmt und die Reaktionsenthalpie gemessen. Pyrolyseversuche in einem Drehrohrreaktor im Kilogramm-Massstab ergeben eine starke Abhaengigkeit des Produktspektrums von der Prozesstemperatur. Insbesondere steigt die Pyrolysegasausbeute auf Kosten der Bildung von Pyrolyseoel und Wasser mit der Temperatur stark an. (orig)

  14. Thermal Treatment of Mercury Mine Wastes Using a Rotary Solar Kiln

    Directory of Open Access Journals (Sweden)

    Andrés Navarro

    2014-01-01

    Full Text Available Thermal desorption, by a rotary kiln of mercury contaminated soil and mine wastes, has been used in order to volatilize mercury from the contaminated medium. Solar thermal desorption is an innovative treatment that uses solar energy to increase the volatility of contaminants, which are removed from a solid matrix by a controlled air flow system. Samples of soils and mine wastes used in the experiments were collected in the abandoned Valle del Azogue mine (SE, Spain, where a complex ore, composed mainly of cinnabar, arsenic minerals (realgar and orpiment and stibnite, was mined. The results showed that thermal treatment at temperatures >400 °C successfully lowered the Hg content (2070–116 ppm to <15 mg kg−1. The lowest values of mercury in treated samples were obtained at a higher temperature and exposition time. The samples that showed a high removal efficiency (>99% were associated with the presence of significant contents of cinnabar and an equivalent diameter above 0.8 mm.

  15. Reduction of phosphate ores by carbon: Part I. Process variables for design of rotary kiln system

    Science.gov (United States)

    Mu, Jacob; Leder, Frederic; Park, Won C.; Hard, Robert A.; Megy, Joseph; Reiss, Howard

    1986-12-01

    Feasibility is established for the reduction of phosphate ores in a rotary kiln, avoiding electric submerged arc furnace technology. This represents a totally new approach to phosphoric acid. Reduction rates of phosphate ore-silica mixtures by carbon in the temperature range of 1100 to 1500 °C under several CO partial pressures in nitrogen were measured in thermogravimetric analyzers. Parameters such as carbon and silica contents, particle and pellet sizes, and gas flow rate were also evaluated with various domestic and foreign phosphate ores. Furthermore, a variety of carbon sources such as subbituminous coals, bituminous coals, anthracite, petroleum coke, and metallurgical coke were tested as reducing agents. Thermodynamic considerations elucidate the temperature dependence of overall conversion as well as the role of excess silica in establishing equilibrium pressure. These findings provide the background for analysis of the kinetics of conversion in Part II of this work. These studies, in conjunction with a previously published work, indicate the importance of intergranular melt phases in the kinetics of otherwise solid state reactions.

  16. Dust storm, northern Mexico

    Science.gov (United States)

    1983-01-01

    This large dust storm along the left side of the photo, covers a large portion of the state of Coahuila, Mexico (27.5N, 102.0E). The look angle of this oblique photo is from the south to the north. In the foreground is the Sierra Madre Oriental in the states Coahuila and Nuevo Leon with the Rio Grande River, Amistad Reservoir and Texas in the background.

  17. Dust acoustic shock wave at high dust density

    International Nuclear Information System (INIS)

    Ghosh, Samiran; Sarkar, Susmita; Khan, Manoranjan; Avinash, K.; Gupta, M. R.

    2003-01-01

    Dust acoustic (DA) shock wave at high dust density, i.e., the dust electroacoustic (DEA) or dust Coulomb (DC) shock wave has been investigated incorporating the nonadiabatic dust charge variation. The nonlinear DEA (DC) shock wave is seen to be governed by the Korteweg-de Vries Burger equation, in which the Burger term is proportional to the nonadiabaticity generated dissipation. It is seen that the shock strength decreases but after reaching minimum, it increases as the dust space charge density |q d n d | increases and the shock strength of DA wave is greater than that of DEA (DC) wave. Moreover the DEA (DC) shock width increases appreciably with increase mass m i of the ion component of the dusty plasma but for DA shock wave the effect is weak

  18. Dust, Climate, and Human Health

    Science.gov (United States)

    Maynard, Nancy G.

    2003-01-01

    Air pollution from both natural and anthropogenic causes is considered to be one of the most serious world-wide environment-related health problems, and is expected to become worse with changes in the global climate. Dust storms from the atmospheric transport of desert soil dust that has been lifted and carried by the winds - often over significant distances - have become an increasingly important emerging air quality issue for many populations. Recent studies have shown that the dust storms can cause significant health impacts from the dust itself as well as the accompanying pollutants, pesticides, metals, salt, plant debris, and other inorganic and organic materials, including viable microorganisms (bacteria, viruses and fungi). For example, thousands of tons of Asian desert sediments, some containing pesticides and herbicides from farming regions, are commonly transported into the Arctic during dust storm events. These chemicals have been identified in animal and human tissues among Arctic indigenous populations. Millions of tons of airborne desert dust are being tracked by satellite imagery, which clearly shows the magnitude as well as the temporal and spatial variability of dust storms across the "dust belt" regions of North Africa, the Middle East, and China. This paper summarizes the most recent findings on the effects of airborne desert dust on human health as well as potential climate influences on dust and health.

  19. Parameterizing the interstellar dust temperature

    Science.gov (United States)

    Hocuk, S.; Szűcs, L.; Caselli, P.; Cazaux, S.; Spaans, M.; Esplugues, G. B.

    2017-08-01

    The temperature of interstellar dust particles is of great importance to astronomers. It plays a crucial role in the thermodynamics of interstellar clouds, because of the gas-dust collisional coupling. It is also a key parameter in astrochemical studies that governs the rate at which molecules form on dust. In 3D (magneto)hydrodynamic simulations often a simple expression for the dust temperature is adopted, because of computational constraints, while astrochemical modelers tend to keep the dust temperature constant over a large range of parameter space. Our aim is to provide an easy-to-use parametric expression for the dust temperature as a function of visual extinction (AV) and to shed light on the critical dependencies of the dust temperature on the grain composition. We obtain an expression for the dust temperature by semi-analytically solving the dust thermal balance for different types of grains and compare to a collection of recent observational measurements. We also explore the effect of ices on the dust temperature. Our results show that a mixed carbonaceous-silicate type dust with a high carbon volume fraction matches the observations best. We find that ice formation allows the dust to be warmer by up to 15% at high optical depths (AV> 20 mag) in the interstellar medium. Our parametric expression for the dust temperature is presented as Td = [ 11 + 5.7 × tanh(0.61 - log 10(AV) ]χuv1/5.9, where χuv is in units of the Draine (1978, ApJS, 36, 595) UV field.

  20. Development of technology to utilize existing tobacco kilns and/or tobacco storage barns for curing (drying) and/or storage of other crops

    Energy Technology Data Exchange (ETDEWEB)

    VanHooren, D L; Scott, J J

    1988-01-01

    This report investigates methods to utilize existing bulk tobacco kilns for curing (drying) of shelled corn, peanuts, and baled hay. In recent years Ontario tobacco producers have had to reduce production levels due to a declining demand for flue-cured tobacco. Many tobacco producers are currently diversifying into other crops. Some of these crops require curing and/or storage. Because of high capital costs to purchase conventional curing and/or storage facilities, tobacco producers wish to reduce their initial diversification costs by modifying their existing tobacco kilns (tobacco drying structures) and/or tobacco storage barns for this purpose. The investigation included high profile and low profile downdraft stick kilns, bulk kilns, and tobacco storage (pack) barns. Corn, peanuts, and hay were considered in relation to bulk kiln specifications and modifications, handling, drying and storage methods, energy requirements, cost, and quality of end product. The conclusions drawn from the study of each product are presented. Results from the projects indicate that: shelled corn can be dried from about 26% moisture content (w.b.) or less; baled hay can be dried from about 27% moisture content (w.b.) or less; and peanuts cured at airflow rates ranging from 169 to 645 l/s/m/sup 3/ of peanuts exhibited no significant differences when evaluated for appearance and flavour. 1 ref., 23 figs., 15 tabs.

  1. Dust in H II regions

    International Nuclear Information System (INIS)

    Isobe, S.

    1977-01-01

    Several pieces of evidence indicate that H II regions may contain dust: 1) the continuum light scattered by dust grains (O'Dell and Hubbard, 1965), 2) thermal radiation from dust grains at infrared wavelengths (Ney and Allen, 1969), 3) the abnormal helium abundance in some H II regions (Peimbert and Costero, 1969), etc. Although observations of the scattered continuum suggest that the H II region cores may be dust-free, dust grains and gas must be well mixed in view of the infrared observations. This difficulty may be solved by introducing globules with sizes approximately 0.001 pc. These globules and the molecular clouds adjacent to H II regions are the main sources supplying dust to H II regions. (Auth.)

  2. Large Aperture Electrostatic Dust Detector

    International Nuclear Information System (INIS)

    Skinner, C.H.; Hensley, R.; Roquemore, A.L.

    2007-01-01

    Diagnosis and management of dust inventories generated in next-step magnetic fusion devices is necessary for their safe operation. A novel electrostatic dust detector, based on a fine grid of interlocking circuit traces biased to 30 or 50 v has been developed for the detection of dust particles on remote surfaces in air and vacuum environments. Impinging dust particles create a temporary short circuit and the resulting current pulse is recorded by counting electronics. Up to 90% of the particles are ejected from the grid or vaporized suggesting the device may be useful for controlling dust inventories. We report measurements of the sensitivity of a large area (5x5 cm) detector to microgram quantities of dust particles and review its applications to contemporary tokamaks and ITER.

  3. Photoelectric charging of dust grains

    International Nuclear Information System (INIS)

    Ignatov, A. M.

    2009-01-01

    Photoemission from the surface of a dust grain in vacuum is considered. It is shown that the cutoff in the energy spectrum of emitted electrons leads to the formation of a steady-state electron cloud. The equation describing the distribution of the electric potential in the vicinity of a dust grain is solved numerically. The dust grain charge is found as a function of the grain size.

  4. Assessment of environmental pollution from brick kilns and their impacts on human health in Bangladesh

    International Nuclear Information System (INIS)

    Azad, A.K.; Iqbal, A.

    2005-01-01

    Bricks are the most essential component for expanding urbanization in Bangladesh. Brick kilns situated all over the country meet the demand of these bricks. But brick fields are causing some environmental problems too. The objective of this study is to identify the pattern of energy consumption in brick fields as well as their impacts on the environment. An attempt has been made to estimate the emission of pollutants (Green house gases and non- green house gases) from brick fields to assess the impacts of the pollutants on human health of the surrounding areas. In Bangladesh, the total number of brick fields is around 6000. Brick fields use coal, wood fuel and crude a mainly for burning bricks in the kiln. Estimation reveals that in Bangladesh for the years 2003-2004, the coal required was 1800 kton while the wood fuel required was 1260 kton. Estimation also reveals that for Bangladesh the annual emission of the pollutants are 7505931.01 tons CO/sub 2/, 943.93 tons CH/sub 4/, 128.40 tons N/sub 2/O, 21763.49 tons NO/sub x/, 40777.21 tons CO, 1698.48 tons NMVOC and 176223.04 tons SO/sub 2/. CO/sub 2/ emission is the most prominent from brick burning. Estimation shows that, for the present level of CO/sub 2/ emission in Bangladesh yearly afforestation required is about 1.4 x 10/sup 9/9 m/sup 2/ area. The emission causes some health problems among both the workers and local inhabitants. The concentration persist around brick fields (200 m) is very high and is 3000 micro g/m/sup 3/ for SO/sub 2/ and 300 micro g/m/sup 3/ for NO/sub x/ and PM-10 during winter, while for summer the concentration is 1000 micro g/m/sup 3/ and 125 micro g/m/sup 3/ respectively. From the high concentration of these pollutants people face some of the health problems. About 30% of the workers suffer from dizziness while 60% feel fatigue. The headache is the most common problem of all the workers and 75% suffer from it. Those working for many years feel fatigue more than the new comers, 55% and 3

  5. Dust in cosmic plasma environments

    International Nuclear Information System (INIS)

    Mendis, D.A.

    1979-01-01

    Cosmic dust is invariably immersed in a plasma and a radiative environment. Consequently, it is charged to some electrostatic potential which depends on the properties of the environment as well as the nature of the dust. This charging affects the physical and dynamical properties of the dust. In this paper the basic aspects of this dust-plasma interaction in several cosmic environments - including planetary magnetospheres, the heliosphere and the interstellar medium - are discussed. The physical and dynamical consequences of the interaction, as well as the pertinent observational evidence, are reviewed. Finally, the importance of the surface charge during the condensation process in plasma environments is stressed. (Auth.)

  6. PIXE analysis of proto-porcelain excavated from the Huoshaoshan kiln site in Deqing County, Zhejiang Province

    International Nuclear Information System (INIS)

    Zhang Bin; Cheng Huansheng; Zheng Jianming

    2014-01-01

    Background: Zhejiang Province is an important producing area of proto-porcelain. Huoshaoshan kiln site in Deqing County is the only kiln known currently for firing proto-porcelain from the late Western Zhou Dynasty to the late Spring and Autumn Period. Also it is the earliest kiln site unearthed for only firing proto-porcelain so far. It is of great significance for the exploration of Chinese early celadon firing technology. Purpose: The aim is to disclose the elemental characteristics of these proto-porcelains and study the sources of the raw materials and relationship between these proto-porcelains. Methods: We selected 18 samples made at the early period (from the late Western Zhou Dynasty to the early Spring and Autumn Period), 15 samples made at the middle and last period (the last period of the middle Spring and Autumn Period), and 17 samples made at the last period (the last period of the late Spring and Autumn Period). Proton Induced X-ray Emission (PIXE) was used to analyze these samples and measure the chemical compositions of these proto-porcelains. The factor analysis is used to study the sources of the raw materials and relationship between these proto-porcelains made in the different periods. Results: The results show that for the raw materials of body and glaze, the proto-porcelains at the last period are different from those at the early period, while the same as those at the middle and last period. Conclusion: PIXE combining with factor analysis can be used to study effectively the sources of the raw materials and relationship between these proto-porcelains. (authors)

  7. Gravitational radiation from dust

    International Nuclear Information System (INIS)

    Isaacson, R.A.; Welling, J.S.; Winicour, J.

    1985-01-01

    A dust cloud is examined within the framework of the general relativistic characteristic initial value problem. Unique gravitational initial data are obtained by requiring that the space-time be quasi-Newtonian. Explicit calculations of metric and matter fields are presented, which include all post-Newtonian corrections necessary to discuss the major physical properties of null infinity. These results establish a curved space version of the Einstein quadrupole formula, in the form ''news function equals third time derivative of transverse quadrupole moment,'' for this system. However, these results imply that some weakened notion of asymptotic flatness is necessary for the description of quasi-Newtonian systems

  8. Dust coagulation in ISM

    Science.gov (United States)

    Chokshi, Arati; Tielens, Alexander G. G. M.; Hollenbach, David

    1989-01-01

    Coagulation is an important mechanism in the growth of interstellar and interplanetary dust particles. The microphysics of the coagulation process was theoretically analyzed as a function of the physical properties of the coagulating grains, i.e., their size, relative velocities, temperature, elastic properties, and the van der Waal interaction. Numerical calculations of collisions between linear chains provide the wave energy in individual particles and the spectrum of the mechanical vibrations set up in colliding particles. Sticking probabilities are then calculated using simple estimates for elastic deformation energies and for the attenuation of the wave energy due to absorption and scattering processes.

  9. The economic benefits of sorting SPF lumber to be kiln-dried on the basis of initial moisture content

    International Nuclear Information System (INIS)

    Warren, S.; Johnson, G.

    1997-01-01

    This study evaluates the economic benefits of sorting green lumber into moisture content classes before kiln-drying. Laser moisture sensing technology was implemented in the sawmill for sorting purposes. The grade outturn and energy savings resulting from shortened drying times were examined. The final moisture content distribution resulting from moisture sorting did not show overdrying or underdrying. Based on grade outturn, the benefits were as much as $15.94 per thousand board feet (MBF) for 2 by 4 by 16 lumber and $19.66 per MBF for 2 by 6 by 16 lumber; energy savings were $1.88 per thousand board feet

  10. Comparison of medieval decorated floor-tiles with clay and tile fragments from the kilns at Bistrup

    International Nuclear Information System (INIS)

    Als Hansen, B.; Aaman Soerensen, M.; McKerrell, H.; Mejdahl, V.

    1977-01-01

    In 1976 two tile kilns with numerous wasters of ornamented tiles were excavated at Bistrup near Roskilde. Identical ornaments had earlier been found on floor-tiles from seven sites, mainly churches, in north and east Zealand. The question arose whether some of these tiles were made locally or whether all tiles carrying this particular ornamentation were made at Bistrup. Preliminary results obtained from a comparison of the tiles with material from Bistrup means of neutron activation analysis indicate that not all tiles were made at Bistrup. (author)

  11. Determination of the Index of Consumption of Petroleum of the Calcining Kiln of the Ernesto Che Guevara Commander Undertaking

    Directory of Open Access Journals (Sweden)

    Yarilys Gaínza-Delgado

    2016-07-01

    Full Text Available This work presents the results obtained in carrying out the mass and energy balances in the calcining kiln of the company commander Ernesto Che Guevara, for determining the consumption index of petroleum used for obtaining nickel oxide through thermal decomposition of the basic nickel carbonate. It was shown that for a production of basic nickel carbonate of              12 t / h with 69% moisture, it is necessary to feed about 1100 kg / h of fuel, for an consumption index of 91.67 kg of fuel per ton of load.

  12. Dust confinement and dust acoustic waves in a magnetized plasma

    Science.gov (United States)

    Piel, A.

    2005-10-01

    Systematic laboratory experiments on dust acoustic waves require the confinement of dust particles. Here we report on new experiments in a magnetized plasma region in front of an additional positively biased disk electrode in a background plasma which is generated in argon at 27MHz between a disk and grid electrode. The plasma diffuses through the grid along the magnetic field. The three-dimensional dust distribution is measured with a horizontal sheet of laser light and a CCD camera, which are mounted on a vertical translation stage. Depending on magnetic field and discharge current, cigar or donut-shaped dust clouds are generated, which tend to rotate about the magnetic field direction. Measurements with emissive probes show that the axial confinement of dust particles with diameters between 0.7-2 μm is achieved by a balance of ion-drag force and electric field force. Dust levitation and radial confinement is due to a strong radial electric field. Dust acoustic waves are destabilized by the ion flow or can be stimulated by a periodic bias on the disk electrode. The observed wave dispersion is compared with fluid and kinetic models of the dust acoustic wave.

  13. Gravimetric dust sampling for control purposes and occupational dust sampling.

    CSIR Research Space (South Africa)

    Unsted, AD

    1997-02-01

    Full Text Available Prior to the introduction of gravimetric dust sampling, konimeters had been used for dust sampling, which was largely for control purposes. Whether or not absolute results were achievable was not an issue since relative results were used to evaluate...

  14. Of data and dust

    CERN Multimedia

    Stephanie Hills

    2016-01-01

    The traditional image of an archive is one of dusty old boxes, books and papers. When your archive is digital, dust spells disaster. An innovative environmental sensor designed and built by a CERN IT specialist has become an essential element in the Laboratory’s data-preservation strategy.   The novel air particle monitoring sensor designed by CERN's Julien Leduc. CERN’s archive holds more than 130 petabytes of data from past and present high-energy physics experiments. Some of it is 40 years old, most of it needs to be kept forever, and all of it is held on tape cartridges (over 20,000 of them). The cartridges are held inside tape libraries with robotic arms that load them into tape drives where they can be read and written. Tape cartridges have many advantages over other data storage media, notably cost and long-term reliability, but topping the list of drawbacks is their vulnerability to contamination from airborne dust particles; a tiny piece of g...

  15. Radionuclides in house dust

    Energy Technology Data Exchange (ETDEWEB)

    Fry, F A; Green, N; Dodd, N J; Hammond, D J

    1985-04-01

    Discharges of radionuclides from the British Nuclear Fuel plc (BNFL) reprocessing plant at Sellafield in Cumbria have led to elevated concentrations radionuclides in the local environment. The major routes of exposure of the public are kept under review by the appropriate authorising Government departments and monitoring is carried out both by the departments and by BNFL itself. Recently, there has been increasing public concern about general environmental contamination resulting from the discharges and, in particular, about possible exposure of members of the public by routes not previously investigated in detail. One such postulated route of exposure that has attracted the interest of the public, the press and Parliament arises from the presence of radionuclides within houses. In view of this obvious and widespread concern, the Board has undertaken a sampling programme in a few communities in Cumbria to assess the radiological significance of this source of exposure. From the results of our study, we conclude that, although radionuclides originating rom the BNFL site can be detected in house dust, this source of contamination is a negligible route of exposure for members of the public in West Cumbria. This report presents the results of the Board's study of house dust in twenty homes in Cumbria during the spring and summer of 1984. A more intensive investigation is being carried out by Imperial College. (author)

  16. Health hazards of cement dust

    International Nuclear Information System (INIS)

    Meo, Sultan A.

    2004-01-01

    ven in the 21st century, millions of people are working daily in a dusty environment. They are exposed to different types of health hazards such as fume, gases and dust, which are risk factors in developing occupational disease. Cement industry is involved in the development of structure of this advanced and modern world but generates dust during its production. Cement dust causes lung function impairment, chronic obstructive lung disease, restrictive lung disease, pneumoconiosis and carcinoma of the lungs, stomach and colon. Other studies have shown that cement dust may enter into the systemic circulation and thereby reach the essentially all the organs of body and affects the different tissues including heart, liver, spleen, bone, muscles and hairs and ultimately affecting their micro-structure and physiological performance. Most of the studies have been previously attempted to evaluate the effects of cement dust exposure on the basis of spirometry or radiology, or both. However, collective effort describing the general effects of cement dust on different organ and systems in humans or animals, or both has not been published. Therefore, the aim of this review is to gather the potential toxic effects of cement dust and to minimize the health risks in cement mill workers by providing them with information regarding the hazards of cement dust. (author)

  17. Dust forecasting system in JMA

    International Nuclear Information System (INIS)

    Mikami, M; Tanaka, T Y; Maki, T

    2009-01-01

    JMAs dust forecasting information, which is based on a GCM dust model, is presented through the JMA website coupled with nowcast information. The website was updated recently and JMA and MOE joint 'KOSA' website was open from April 2008. Data assimilation technique will be introduced for improvement of the 'KOSA' information.

  18. Study of the presence of fluorine in the recycled fractions during carbothermal treatment of EAF dust.

    Science.gov (United States)

    Menad, N; Ayala, J N; Garcia-Carcedo, Fernando; Ruiz-Ayúcar, E; Hernández, A

    2003-01-01

    Carbothermal treatment tests of electric arc furnace dusts (EAFD) using the Waelz kiln process were carried out in pilot-scale for the production of zinc oxide. The association of halides in the EAFD, and the recycled products, such as zinc oxide fumes and high-grade iron contents fractions were examined by X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) analysis. XRD reveals the presence of chlorine and fluorine in the dusts in the form of KCl, NaCl and CaF2. An ultra-pure fraction of zinc was obtained after the Double Leaching Waelz Oxide (DLWO) process was performed on the zinc oxide fumes. The halide contents were reduced to approximately 100 ppm Cl and 700 ppm F. The rest of these elements are in the form of CaF2. About 65% F is volatilised as lead and zinc fluorides, 15% is expected in the magnetic fractions and 20% in non-magnetic fractions as CaF2 and MnF2, respectively.

  19. Dust in flowing magnetized plasma

    International Nuclear Information System (INIS)

    Pandey, Birendra P.; Samarian, Alex A.; Vladimirov, Sergey V.

    2009-01-01

    Plasma flows occur in almost every laboratory device and interactions of flowing plasmas with near-wall impurities and/or dust significantly affects the efficiency and lifetime of such devices. The charged dust inside the magnetized flowing plasma moves primarily under the influence of the plasma drag and electric forces. Here, the charge on the dust, plasma potential, and plasma density are calculated self-consistently. The electrons are assumed non-Boltzmannian and the effect of electron magnetization and electron-atom collisions on the dust charge is calculated in a self-consistent fashion. For various plasma magnetization parameters viz. the ratio of the electron and ion cyclotron frequencies to their respective collision frequencies, plasma-atom and ionization frequencies, the evolution of the plasma potential and density in the flow region is investigated. The variation of the dust charge profile is shown to be a sensitive function of plasma parameters. (author)

  20. Dust in protoplanetary disks: observations*

    Directory of Open Access Journals (Sweden)

    Waters L.B.F.M.

    2015-01-01

    Full Text Available Solid particles, usually referred to as dust, are a crucial component of interstellar matter and of planet forming disks surrounding young stars. Despite the relatively small mass fraction of ≈1% (in the solar neighborhood of our galaxy; this number may differ substantially in other galaxies that interstellar grains represent of the total mass budget of interstellar matter, dust grains play an important role in the physics and chemistry of interstellar matter. This is because of the opacity dust grains at short (optical, UV wavelengths, and the surface they provide for chemical reactions. In addition, dust grains play a pivotal role in the planet formation process: in the core accretion model of planet formation, the growth of dust grains from the microscopic size range to large, cm-sized or larger grains is the first step in planet formation. Not only the grain size distribution is affected by planet formation. Chemical and physical processes alter the structure and chemical composition of dust grains as they enter the protoplanetary disk and move closer to the forming star. Therefore, a lot can be learned about the way stars and planets are formed by observations of dust in protoplanetary disks. Ideally, one would like to measure the dust mass, the grain size distribution, grain structure (porosity, fluffiness, the chemical composition, and all of these as a function of position in the disk. Fortunately, several observational diagnostics are available to derive constrains on these quantities. In combination with rapidly increasing quality of the data (spatial and spectral resolution, a lot of progress has been made in our understanding of dust evolution in protoplanetary disks. An excellent review of dust evolution in protoplanetary disks can be found in Testi et al. (2014.

  1. Effects of Co-Processing Sewage Sludge in the Cement Kiln on PAHs, Heavy Metals Emissions and the Surrounding Environment.

    Science.gov (United States)

    Lv, Dong; Zhu, Tianle; Liu, Runwei; Li, Xinghua; Zhao, Yuan; Sun, Ye; Wang, Hongmei; Zhang, Fan; Zhao, Qinglin

    2018-04-08

    To understand the effects of co-processing sewage sludge in the cement kiln on non-criterion pollutants emissions and its surrounding environment, the flue gas from a cement kiln stack, ambient air and soil from the background/downwind sites were collected in the cement plant. Polycyclic aromatic hydrocarbons (PAHs) and heavy metals of the samples were analyzed. The results show that PAHs in flue gas mainly exist in the gas phase and the low molecular weight PAHs are the predominant congener. The co-processing sewage sludge results in the increase in PAHs and heavy metals emissions, especially high molecular weight PAHs and low-volatile heavy metals such as Cd and Pb in the particle phase, while it does not change their compositions and distribution patterns significantly. The concentrations and their distributions of the PAHs and heavy metals between the emissions and ambient air have a positive correlation and the co-processing sewage sludge results in the increase of PAHs and heavy metals concentrations in the ambient air. The PAHs concentration level and their distribution in soil are proportional to those in the particle phase of flue gas, and the co-processing sewage sludge can accelerate the accumulation of the PAHs and heavy metals in the surrounding soil, especially high/middle molecular weight PAHs and low-volatile heavy metals.

  2. Potential to use waste tires as supplemental fuel in pulp and paper mill boilers, cement kilns and in road pavement

    Energy Technology Data Exchange (ETDEWEB)

    Barlaz, M.A.; Eleazer, W.E. II (North Carolina State Univ., Raleigh, NC (United States). Dept. of Civil Engineering); Whittle, D.J.

    1993-12-01

    The objective of this paper is to evaluate the recycling potential of waste tires as an energy source and for use in road pavement. North Carolina, U.S.A., is used as a case study. Scrap tires may be burned for supplemental fuel in pulp and paper mill boilers and cement kilns. Five pulp and paper mill boilers in North Carolina could consume over 90% of the 6 million tires generated annually in the state. Cement kilns located within 400 km of North Carolina population centers could consume about 6.6 million tires annually. Based on the quantity of pavement laid in North Carolina, non-proprietary and proprietary versions of asphalt rubber concrete have the potential to consume 1.8 and 7.2 million tires, respectively. Rubber modified asphalt concrete has the potential to consume up to 16.5 million tires. However, technological and economic limitations suggest that large scale implementation is unlikely for the short term. Environmental considerations pertaining to each alternative are discussed. (author)

  3. Brick and lime kilns in Ecuador. An example of woodfuel use in third world, small-scale industry

    Energy Technology Data Exchange (ETDEWEB)

    Barriga, A.; Duque, J.; Moreira, E.; Zabala, G.; Solis, M.; Marcial, J.; Carlozama, J. [Escuela Superior Politechnica del Litoral (ESPOL), Guayaquil (Ecuador); Svenningsson, P.J. [Stockholm Environment Inst. (Sweden)

    1992-12-31

    At the present, early stage of this project, it has been verified that the energy requirements in lime making are of the order of 5 to 10 MJ/kg limestone in continuous shaft kilns. Furthermore, there are no lime making practices applied in Ecuador that point towards any easy way of substantially reducing energy usage. The theoretical analysis, including comparison with systems that either use low-volatile fuels or guarantee the complete combustion of volatiles, shows the great importance that should be attached to complete combustion of the fuel. A substantial improvement in efficiency can be expected if the volatiles can be utilized through the introduction of secondary air, recirculation of gases, or devolatilization of the wood before it enters the shaft. Such schemes do however need to be cost effective as well, meaning that the investment cost, especially for more advanced components, has to be low. There may be some solutions to this, including construction of very simple, brick-made, wood pre-gasification chambers that are integrated with the shaft kiln. This will hopefully be looked into further during the next phases of this project. (12 refs., 12 figs., 12 tabs.)

  4. The Influence of Log Felling Season on the Extent of Discoloration in Rubberwood Sawn Timber during the Kiln Drying Process

    Directory of Open Access Journals (Sweden)

    Jegatheswaran Ratnasingam

    2016-04-01

    Full Text Available This study investigated the effects of felling season on the discoloration of rubberwood sawn timber during conventional kiln drying. The samples were collected throughout the year 2015 to monitor the variation of free sugars and starch content in the rubberwood logs. Two batches of logs, one from the rainy season and the other from the dry season, were felled and sawn for experimentation. The findings showed that discoloration was more prominent in sawn timber obtained from logs felled during the dry season. The amount of free sugars and starch in the logs had a strong influence on the extent of discoloration in the rubberwood sawn timber during the kiln drying process. A higher amount of free sugars and starch in the logs felled during the dry season increased the incidence of blue stain on these logs. The results of this study conclusively showed that discoloration in rubberwood can be minimized by the choice of log felling season and the use of an appropriate drying technique, which will inevitably improve the aesthetic appeal of the wood.

  5. COAL DUST EMISSION PROBLEM

    Directory of Open Access Journals (Sweden)

    M. M. Biliaiev

    2016-12-01

    Full Text Available Purpose. The article aims to develop 2D numerical models for the prediction of atmospheric pollution during transportation of coal in the railway car, as well as the ways to protect the environment and the areas near to the mainline from the dust emission due to the air injection installation. Methodology. To solve this problem there were developed numerical models based on the use of the equations of motion of an inviscid incompressible fluid and mass transfer. For the numerical integration of the transport equation of the pollutant the implicit alternating-triangular difference scheme was used. For numerical integration of the 2D equation for the velocity potential the method of total approximation was used. The developed numerical models are the basis of established software package. On the basis of the constructed numerical models it was carried out a computational experiment to assess the level of air pollution when transporting bulk cargo by rail when the railway car has the air injection. Findings. 2D numerical models that belong to the class «diagnostic models» were developed. These models take into account the main physical factors affecting the process of dispersion of dust pollution in the atmosphere during transportation of bulk cargo. The developed numerical models make it possible to calculate the dust loss process, taking into account the use of the air injection of the car. They require a small cost of the computer time during practical realization at the low and medium power machines. There were submitted computational calculations to determine pollutant concentrations and the formation of the zone of pollution near the train with bulk cargo in «microscale» scale taking into account the air curtains. Originality. 2D numerical models taking into account the relevant factors influencing the process of dispersion of pollutants in the atmosphere, and the formation of the zone of pollution during transportation of bulk cargo by

  6. Dust of dark energy

    International Nuclear Information System (INIS)

    Lim, Eugene A.; Sawicki, Ignacy; Vikman, Alexander

    2010-01-01

    We introduce a novel class of field theories where energy always flows along timelike geodesics, mimicking in that respect dust, yet which possess non-zero pressure. This theory comprises two scalar fields, one of which is a Lagrange multiplier enforcing a constraint between the other's field value and derivative. We show that this system possesses no wave-like modes but retains a single dynamical degree of freedom. Thus, the sound speed is always identically zero on all backgrounds. In particular, cosmological perturbations reproduce the standard behaviour for hydrodynamics in the limit of vanishing sound speed. Using all these properties we propose a model unifying Dark Matter and Dark Energy in a single degree of freedom. In a certain limit this model exactly reproduces the evolution history of ΛCDM, while deviations away from the standard expansion history produce a potentially measurable difference in the evolution of structure

  7. Fiscal 2000 feasibility research on environmentally-friendly coal utilization system. Feasibility research project (Clinkering technology for fluidized bed cement kiln - China); 2000 nendo kankyo chowagata sekitan riyo system kanosei chosa hokokusho. Jisshi kanosei chosa jigyo (ryudosho cement kiln shosei gijutsu Chugoku)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Studies are conducted about the feasibility of the above-named technology in China, its energy conservation and environmental protection effects, and so forth. To be expected upon conversion of shaft kilns in China to fluidized bed kilns using this technology are energy conservation of approximately 30%; resultant reduction in greenhouse effect gas emissions, in the scattering of coarse particulates, and in NOx and SOx emissions, these in combination contributing to reduction in environmental pollution; stable production of high-quality clinker; preference to inexpensive fuels and the effective utilization of resources; reduction in the cement manufacturing cost; and so forth. On-site surveys were conducted at existing shaft kiln plants, and studies were made about conversion to fluidized bed cement kilns with a 1,000 tons/day capability. The conclusion was that the period of return on invested capital would be 3.94-8.98 years, dependent upon the degree of facilities renovation, showing the presence of high possibilities of a successful return on invested capital. It was estimated that the shaft kilns would bring about a yearly reduction of 840 tons of coarse particulates, 105 tons of SO{sub 2}, and 68,281 tons of CO2. (NEDO)

  8. Ulysses dust measurements near Jupiter.

    Science.gov (United States)

    Grün, E; Zook, H A; Baguhl, M; Fechtig, H; Hanner, M S; Kissel, J; Lindblad, B A; Linkert, D; Linkert, G; Mann, I B

    1992-09-11

    Submicrometer- to micrometer-sized particles were recorded by the Ulysses dust detector within 40 days of the Jupiter flyby. Nine impacts were recorded within 50 Jupiter radii with most of them recorded after closest approach. Three of these impacts are consistent with particles on prograde orbits around Jupiter and the rest are believed to have resulted from gravitationally focused interplanetary dust. From the ratio of the impact rate before the Jupiter flyby to the impact rate after the Jupiter flyby it is concluded that interplanetary dust particles at the distance of Jupiter move on mostly retrograde orbits. On 10 March 1992, Ulysses passed through an intense dust stream. The dust detector recorded 126 impacts within 26 hours. The stream particles were moving on highly inclined and apparently hyperbolic orbits with perihelion distances of >5 astronomical units. Interplanetary dust is lost rather quickly from the solar system through collisions and other mechanisms and must be almost continuously replenished to maintain observed abundances. Dust flux measurements, therefore, give evidence of the recent rates of production from sources such as comets, asteroids, and moons, as well as the possible presence of interstellar grains.

  9. Experiments on Dust Grain Charging

    Science.gov (United States)

    Abbas, M. N.; Craven, P. D.; Spann, J. F.; Tankosic, D.; LeClair, A.; West, E. A.

    2004-01-01

    Dust particles in various astrophysical environments are charged by a variety of mechanisms generally involving collisional processes with other charged particles and photoelectric emission with UV radiation from nearby sources. The sign and the magnitude of the particle charge are determined by the competition between the charging processes by UV radiation and collisions with charged particles. Knowledge of the particle charges and equilibrium potentials is important for understanding of a number of physical processes. The charge of a dust grain is thus a fundamental parameter that influences the physics of dusty plasmas, processes in the interplanetary medium and interstellar medium, interstellar dust clouds, planetary rings, cometary and outer atmospheres of planets etc. In this paper we present some results of experiments on charging of dust grains carried out on a laboratory facility capable levitating micron size dust grains in an electrodynamic balance in simulated space environments. The charging/discharging experiments were carried out by exposing the dust grains to energetic electron beams and UV radiation. Photoelectric efficiencies and yields of micron size dust grains of SiO2, and lunar simulates obtained from NASA-JSC will be presented.

  10. PO43 Removal by and Permeability of Industrial Byproducts and Minerals: Granulated Blast Furnace Slag, Cement Kiln Dust, Coconut Shell Activated Carbon, Silica Sand and Zeolite

    Science.gov (United States)

    Excess aqueous concentration of phosphate degrades the overall water quality of the receiving surface waters in a cumulatively damaging process referred to as eutrophication. Adsorption of excess phosphate has proven to be the most effective, and economical methods of phosphate removal from such wat...

  11. Influence of chemical and physical characteristics of cement kiln dusts (CKDs) on their hydration behavior and potential suitability for soil stabilization

    International Nuclear Information System (INIS)

    Peethamparan, Sulapha; Olek, Jan; Lovell, Janet

    2008-01-01

    The interaction of CKDs with a given soil depends on the chemical and physical characteristics of the CKDs. Hence, the characterization of CKDs and their hydration products may lead to better understanding of their suitability as soil stabilizers. In the present article, four different CKD powders are characterized and their hydration products are evaluated. A detailed chemical (X-ray diffraction), thermogravimetric and morphological (scanning electron microscope) analyses of both the CKD powders and the hydrated CKD pastes are presented. In general, high free-lime content (∼ 14-29%) CKDs, when reacted with water produced significant amounts of calcium hydroxide, ettringite and syngenite. These CKDs also developed higher unconfined compressive strength and higher temperature of hydration compared to CKDs with lower amounts of free-lime. An attempt was made to qualitatively correlate the performance of CKD pastes with the chemical and physical characteristics of the original CKD powders and to determine their potential suitability as soil stabilizers. To that effect a limited unconfined compressive strength testing of CKD-treated kaolinite clays was performed. The results of this study suggest that both the compressive strength and the temperature of hydration of the CKD paste can give early indications of the suitability of particular CKD for soil stabilization

  12. SUPERFUND TREATABILITY CLEARINGHOUSE: FULL SCALE ROTARY KILN INCINERATOR FIELD TRIAL: PHASE I, VERIFICATION TRIAL BURN ON DIOXIN/HERBICIDE ORANGE CONTAMINATED SOIL

    Science.gov (United States)

    This treatability study reports on the results of one of a series of field trials using various remedial action technologies that may be capable of restoring Herbicide Orange (HO)XDioxin contaminated sites. A full-scale field trial using a rotary kiln incinerator capable of pro...

  13. THE FATE OF TRACE METALS IN A ROTARY KILN INCINERATOR WITH A VENTURI/PACKED COLUMN SCRUBBER - VOLUME I: TECHNICAL RESULTS

    Science.gov (United States)

    A five week series of pilot-scale incineration tests, using a synthetic waste feed, was performed at the Environmental Protection Agency's Incineration Research Facility to evaluate the fate of trace metals fed to a rotary kiln incinerator. Eight tests studied the fate of five ha...

  14. A dust-free dock

    Energy Technology Data Exchange (ETDEWEB)

    Merrion, D. [E & F Services Ltd. (United Kingdom)

    2002-10-01

    This paper describes the process of unloading coal, petcoke and other dusty products in environmentally-sensitive areas. It presents a case study of the deepwater Port of Foynes on the west coast of Ireland which imports animal feed, fertiliser, coal and cement clinker, where dockside mobile loaders (DMLs) have eliminated spillage and controlled dust, and a record case study of the Humber International Terminal in the UK, where air curtinas, dust suppression grids and EFFEX{reg_sign} filters overcome the dust problems. 2 photos.

  15. Triton's streaks as windblown dust

    Science.gov (United States)

    Sagan, Carl; Chyba, Christopher

    1990-01-01

    Explanations for the surface streaks observed by Voyager 2 on Triton's southern hemisphere are discussed. It is shown that, despite Triton's tenuous atmosphere, low-cohesion dust trains with diameters of about 5 micron or less may be carried into suspension by aeolian surface shear stress, given expected geostrophic wind speeds of about 10 m/s. For geyser-like erupting dust plumes, it is shown that dust-settling time scales and expected wind velocities can produce streaks with length scales in good agreement with those of the streaks. Thus, both geyserlike eruptions or direct lifting by surface winds appear to be viable mechanisms for the origin of the streaks.

  16. [Asthma due to grain dust].

    Science.gov (United States)

    Baur, X; Preisser, A; Wegner, R

    2003-06-01

    The actual literature as well as two case reports described in detail show that grain dust induces asthmatic reactions and ODTS which are obviously not of allergic origin. For diagnosis occupational-type exposure tests are decisive whereas allergological testing usually is not. Endotoxins which are present in the grain dust samples in high concentrations have to be regarded as the major causative components. To avoid irreversible lung function impairment a comprehensive early diagnosis is necessary. Generally, a remarkable reduction of exposure to dust with high levels of airborne endotoxin in agriculture has to be achieved since in many workplaces corresponding exposures are still rather high.

  17. Dust Dynamics Near Planetary Surfaces

    Science.gov (United States)

    Colwell, Joshua; Hughes, Anna; Grund, Chris

    Observations of a lunar "horizon glow" by several Surveyor spacecraft in the 1960s opened the study of the dynamics of charged dust particles near planetary surfaces. The surfaces of the Moon and other airless planetary bodies in the solar system (asteroids, and other moons) are directly exposed to the solar wind and ionizing solar ultraviolet radiation, resulting in a time-dependent electric surface potential. Because these same objects are also exposed to bombardment by micrometeoroids, the surfaces are usually characterized by a power-law size distribution of dust that extends to sub-micron-sized particles. Individual particles can acquire a charge different from their surroundings leading to electrostatic levitation. Once levitated, particles may simply return to the surface on nearly ballistic trajectories, escape entirely from the moon or asteroid if the initial velocity is large, or in some cases be stably levitated for extended periods of time. All three outcomes have observable consequences. Furthermore, the behavior of charged dust near the surface has practical implications for planned future manned and unmanned activities on the lunar surface. Charged dust particles also act as sensitive probes of the near-surface plasma environment. Recent numerical modeling of dust levitation and transport show that charged micron-sized dust is likely to accumulate in topographic lows such as craters, providing a mechanism for the creation of dust "ponds" observed on the asteroid 433 Eros. Such deposition can occur when particles are supported by the photoelectron sheath above the dayside and drift over shadowed regions of craters where the surface potential is much smaller. Earlier studies of the lunar horizon glow are consistent with those particles being on simple ballistic trajectories following electrostatic launching from the surface. Smaller particles may be accelerated from the lunar surface to high altitudes consistent with observations of high altitude

  18. Bounded dust-acoustic waves in a cylindrically bounded collisional dusty plasma with dust charge variation

    International Nuclear Information System (INIS)

    Wei Nanxia; Xue Jukui

    2006-01-01

    Taking into account the boundary, particle collisions, and dust charging effects, dust-acoustic waves in a uniform cylindrically bounded dusty plasma is investigated analytically, and the dispersion relation for the dust-acoustic wave is obtained. The effects of boundary, dust charge variation, particle collision, and dust size on the dust-acoustic wave are discussed in detail. Due to the bounded cylindrical boundary effects, the radial wave number is discrete, i.e., the spectrum is discrete. It is shown that the discrete spectrum, the adiabatic dust charge variation, dust grain size, and the particle collision have significant effects on the dust-acoustic wave

  19. Dust particle formation in silane plasmas

    NARCIS (Netherlands)

    Sorokin, M.

    2005-01-01

    Dust can be found anywhere: in the kitchen, in the car, in space… Not surprisingly we also see dust in commercial and laboratory plasmas. Dust can be introduced in the plasma, but it can also grow there by itself. In the microelectronics industry, contamination of the processing plasma by dust is an

  20. PERSPECTIVE: Dust, fertilization and sources

    Science.gov (United States)

    Remer, Lorraine A.

    2006-11-01

    Aerosols, tiny suspended particles in the atmosphere, play an important role in modifying the Earth's energy balance and are essential for the formation of cloud droplets. Suspended dust particles lifted from the world's arid regions by strong winds contain essential minerals that can be transported great distances and deposited into the ocean or on other continents where productivity is limited by lack of usable minerals [1]. Dust can transport pathogens as well as minerals great distance, contributing to the spread of human and agricultural diseases, and a portion of dust can be attributed to human activity suggesting that dust radiative effects should be included in estimates of anthropogenic climate forcing. The greenish and brownish tints in figure 1 show the wide extent of monthly mean mineral dust transport, as viewed by the MODerate resolution Imaging Spectroradiometer (MODIS) satellite sensor. The monthly mean global aerosol system for February 2006 from the MODIS aboard the Terra satellite Figure 1. The monthly mean global aerosol system for February 2006 from the MODIS aboard the Terra satellite. The brighter the color, the greater the aerosol loading. Red and reddish tints indicate aerosol dominated by small particles created primarily from combustion processes. Green and brownish tints indicate larger particles created from wind-driven processes, usually transported desert dust. Note the bright green band at the southern edge of the Saharan desert, the reddish band it must cross if transported to the southwest and the long brownish transport path as it crosses the Atlantic to South America. Image courtesy of the NASA Earth Observatory (http://earthobservatory.nasa.gov). Even though qualitatively we recognize the extent and importance of dust transport and the role that it plays in fertilizing nutrient-limited regions, there is much that is still unknown. We are just now beginning to quantify the amount of dust that exits one continental region and the

  1. Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): Emissions of particulate matter from garbage burning, wood and dung cooking fires, motorcycles and brick kilns

    Science.gov (United States)

    Jayarathne, T. S.; Rathnayake, C.; Stockwell, C.; Daugherty, K.; Islam, R. M.; Christian, T. J.; Bhave, P.; Praveen, P. S.; Panday, A. K.; Adhikari, S.; Rasmi, M.; Goetz, D.; DeCarlo, P. F.; Saikawa, E.; Yokelson, R. J.; Stone, E. A.

    2016-12-01

    The Nepal Ambient Monitoring and Source Testing Experiment (NAMASTE) field campaign targeted the in-situ characterization of widespread and under-sampled combustion sources in South Asia by determining emission factors (EF) for fine particulate matter (PM2.5), organic carbon (OC), elemental carbon, inorganic ions, trace metals, and organic species. Garbage burning had the highest EF PM2.5 among the sampled sources ranging 7-124 g kg-1, with maximum EFs for garbage burned under higher moisture conditions. Garbage burning emissions contained high concentrations of polycyclic aromatic compounds (PAHs) and heavy metals (Pb, Cd, Zn) that are associated with acute and chronic health effects. Triphenylbenzene and antimony (Sb) were unique to garbage burning are good candidates for tracing this source. Cook stove emissions varied largely by stove technology (traditional mud stove, 3-stone cooking fire, chimney stove, etc.) and biomass fuel (dung, hardwood, twigs, and mixtures thereof). Burning dung consistently emitted more PM2.5 than burning wood and contained characteristic fecal sterols and stanols. Motorcycle emissions were evaluated before and after servicing, which decreased EF PM2.5 from 8.8 g kg-1 to 0.7 g kg-1. Organic species analysis indicated that this reduction in PM2.5­ is largely due to a decrease in emission of motor oil. For brick kilns, the forced draft zig-zag kilns had higher EF PM2.5 (12-19 g kg-1) compared to clamp kilns (8-13 g kg-1) and also exhibited chemical differences. PM2.5 emitted from the zig-zag kiln were mainly OC (7%), sulfate (32%) and uncharacterized chemical components (60%), while clamp kiln emissions were dominated by OC (64%) and ammonium sulfate (36%). The quantitative emission factors developed in this study may be used for source apportionment and to update regional emission inventories.

  2. Loess and Eolian Dust Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past environment derived from Loess and Eolian dust (silt-sized material deposited on the Earth surface by the surface winds. Parameter keywords describe...

  3. 75 FR 3881 - Combustible Dust

    Science.gov (United States)

    2010-01-25

    ..., rubber, drugs, dried blood, dyes, certain textiles, and metals (such as aluminum and magnesium..., furniture manufacturing, metal processing, fabricated metal products and machinery manufacturing, pesticide... standard that will comprehensively address the fire and explosion hazards of combustible dust. The Agency...

  4. Rethinking wood dust safety standards

    OpenAIRE

    Ratnasingam, Jega; Wai, Lim Tau; Ramasamy, Geetha; Ioras, Florin; Tadin, Ishak; Universiti Putra Malaysia; Buckinghamshire New University; Centre for Occupational Safety and Health Singapore

    2015-01-01

    The current universal work safety and health standards pertaining to wood dust in factories lack the localisation required. As a study has shown, there is a urgent need to reevaluate the current guidelines and practices.

  5. Physical properties of five grain dust types.

    OpenAIRE

    Parnell, C B; Jones, D D; Rutherford, R D; Goforth, K J

    1986-01-01

    Physical properties of grain dust derived from five grain types (soybean, rice, corn, wheat, and sorghum) were measured and reported. The grain dusts were obtained from dust collection systems of terminal grain handling facilities and were assumed to be representative of grain dust generated during the handling process. The physical properties reported were as follows: particle size distributions and surface area measurements using a Coulter Counter Model TAII; percent dust fractions less tha...

  6. Efficient radiative transfer in dust grain mixtures

    OpenAIRE

    Wolf, S.

    2002-01-01

    The influence of a dust grain mixture consisting of spherical dust grains with different radii and/or chemical composition on the resulting temperature structure and spectral energy distribution of a circumstellar shell is investigated. The comparison with the results based on an approximation of dust grain parameters representing the mean optical properties of the corresponding dust grain mixture reveal that (1) the temperature dispersion of a real dust grain mixture decreases substantially ...

  7. Grain dust and the lungs.

    Science.gov (United States)

    Chan-Yeung, M.; Ashley, M. J.; Grzybowski, S.

    1978-01-01

    Grain dust is composed of a large number of materials, including various types of grain and their disintegration products, silica, fungi, insects and mites. The clinical syndromes described in relation to exposure to grain dust are chronic bronchitis, grain dust asthma, extrinsic allergic alveolitis, grain fever and silo-filler's lung. Rhinitis and conjunctivitis are also common in grain workers. While the concentration and the quality of dust influence the frequency and the type of clinical syndrome in grain workers, host factors are also important. Of the latter, smoking is the most important factor influencing the frequency of chronic bronchitis. The role of atopy and of bronchial hyperreactivity in grain dust asthma has yet to be assessed. Several well designed studies are currently being carried out in North America not only to delineate the frequency of the respiratory abnormalities, the pathogenetic mechanisms and the host factors, but also to establish a meaningful threshold limit concentration for grain dust. Images p1272-a PMID:348288

  8. Charged dust structures in plasmas

    International Nuclear Information System (INIS)

    Cramer, N.F.; Vladimirov, S.V.

    1999-01-01

    We report here on theoretical investigations of the mechanical-electrostatic modes of vibration of a dust-plasma crystal, extending earlier work on the transverse modes of a horizontal line of grains (where the ions flow vertically downward to a plane horizontal cathode), the modes of two such lines of grains, and the modes of a vertical string of grains. The last two arrangements have the unique feature that the effect of the background plasma on the mutual grain interaction is asymmetric because of the wake downstream of the grains studied in. The characteristic frequencies of the vibrations are dependent on the parameters of the plasma and the dust grains, such as the Debye length and the grain charge, and so measurement of the frequencies could provide diagnostics of these quantities. Although the current boom in dusty plasma research is driven mainly by such industrial applications as plasma etching, sputtering and deposition, the physical outcomes of investigations in this rapidly expanding field cover many important topics in space physics and astrophysics as well. Examples are the interaction of dust with spacecraft, the structure of planetary rings, star formation, supernova explosions and shock waves. In addition, the study of the influence of dust in environmental research, such as in the Earth's ionosphere and atmosphere, is important. The unique binding of dust particles in a plasma opens possibilities for so-called super-chemistry, where the interacting bound elements are not atoms but dust grains

  9. Suspended dust in Norwegian cities

    International Nuclear Information System (INIS)

    2001-01-01

    According to calculations, at least 80 000 people in Oslo and 8 000 in Trondheim were annoyed by too much suspended dust in 2000. The dust concentration is greatest in the spring, presumably because dust is swirling up from melting snow and ice on the streets. Car traffic is the main source of the dust, except for some of the most highly exposed regions where wood-firing from old stoves contributes up to 70 percent of the dust. National targets for air quality include suspended dust, nitrogen dioxide, sulphur dioxide and benzene. Calculations show that nitrogen dioxide emissions exceeding the limit affected 4 000 people in Oslo and 1 000 people in Trondheim. The sulphur dioxide emissions in the major cities did non exceed the national quality limit; they did exceed the limit in some of the smaller industrial centres. In Trondheim, measurements show that the national limit for benzene was exceeded. Most of the emission of nitrogen dioxide comes from the road traffic. Local air pollution at times causes considerable health- and well-being problems in the larger cities and industrial centres, where a great part of the population may be at risk of early death, infection of the respiratory passage, heart- and lung diseases and cancer

  10. High-frequency and microwave heating as a pretreatment to kiln drying of hollowed-out timber

    International Nuclear Information System (INIS)

    Yamada, N.; Okumura, S.; Taniguchi, Y.

    2001-01-01

    To dry hollowed-out timber without V-shaped drying checks, its inner part should be dried faster than the outer part. The feasibility of high frequency heating and microwave heating as a pretreatment of kiln drying of hollow timber was examined. During high frequency heating, the top and bottom parts of the timber were dried faster than the right and left parts because the central hollow acts as an air-gap. The outer part dried faster than the inner part during microwave heating, probably because of insufficient penetration of microwave energy into the inner part. The uneven heating of hollowed timber was improved by turning the specimen around its axis during high frequency heating and by setting the specimen upright in the microwave oven

  11. Modelling of carbonisation of renewable fuels in a rotary kiln reactor; Modellierung der Karbonisierung nachwachsender Rohstoffe im Drehrohrreaktor

    Energy Technology Data Exchange (ETDEWEB)

    Klose, W; Schinkel, A P [Univ. Kassel (Germany). Inst. fuer Thermische Energietechnik

    1998-09-01

    The contribution models the pyrolysis of corn in a rotary kiln reactor. The model comprises a solution of the two-dimensional energy and mass balances for the solid phase. The movement of the solid matter inside the reactor is described by model equations. The influence of various operating parameters on the pyrolysis process is discussed, i.e. temperature, rotational speed, length and angle of inclination of the tube. (orig.) [Deutsch] In diesem Beitrag wird die Pyrolyse von Mais im Drehrohrreaktor modelliert. Das Modell beinhaltet die Loesung der 2dimensionalen Energie- und Stoffbilanzen fuer die feste Phase. Die Gutbewegung im Drehrohr wird mit Hilfe von Modellansaetzen beschrieben. Es wird der Einfluss der Betriebsparameter Temperatur, Drehzahl, Laenge und Neigungswinkel des Rohres auf die Pyrolyse diskutiert. (orig.)

  12. Emissions from carpet combustion in a pilot-scale rotary kiln: comparison with coal and particle-board combustion

    Energy Technology Data Exchange (ETDEWEB)

    Stephanie Lucero Konopa; James A. Mulholland; Matthew J. Realff; Paul M. Lemieux [Georgia Institute of Technology, Atlanta, GA (United States). School of Civil and Environmental Engineering

    2008-08-15

    The use of post-consumer carpet as a potential fuel substitute in cement kilns and other high-temperature processes is being considered to address the problem of huge volumes of carpet waste and the opportunity of waste-to-energy recovery. Carpet represents a high volume waste stream, provides high energy value, and contains other recoverable materials for the production of cement. This research studied the emission characteristics of burning 0.46-kg charges of chopped nylon carpet squares, pulverized coal, and particle-board pellets in a pilot-scale natural gas-fired rotary kiln. Carpet was tested with different amounts of water added. Emissions of oxygen, carbon dioxide, nitric oxide (NO), sulfur dioxide (SO{sub 2}), carbon monoxide (CO), and total hydrocarbons and temperatures were continuously monitored. It was found that carpet burned faster and more completely than coal and particle board, with a rapid volatile release that resulted in large and variable transient emission peaks. NO emissions from carpet combustion ranged from 0.06 to 0.15 g/MJ and were inversely related to CO emissions. Carpet combustion yielded higher NO emissions than coal and particleboard combustion, consistent with its higher nitrogen content. S{sub 2} emissions were highest for coal combustion, consistent with its higher sulfur content than carpet or particle board. Adding water to carpet slowed its burn time and reduced variability in the emission transients, reducing the CO peak but increasing NO emissions. Results of this study indicate that carpet waste can be used as an effective alternative fuel, with the caveats that it might be necessary to wet carpet or chop it finely to avoid excessive transient puff emissions due to its high volatility compared with other solid fuels, and that controlled mixing of combustion air might be used to control NO emissions from nylon carpet. 13 refs., 5 figs., 1 tab.

  13. Study on treatment of dust by dismantling

    International Nuclear Information System (INIS)

    Torikai, K.; Suzuki, K.

    1987-01-01

    In dismantling of nuclear reactors, various kinds of treatment of dust generated by cutting or dismantling concrete structures of components of reactors are evaluated for safety, cost, and performance comparing the work in air with water. A method of dust treatment for work in air is discussed. The dry method has an easy operation in practice and a good performance in the equipment, but has problem on the prevention from radioactive contamination by diffusion of dust in air. For the purpose of advancing the strong points and eliminating the weak points in dry method, an improved venturi scrubber system is proposed for dismantling work as a dust collecting system. The system consists of dust absorbing pipe, dust collector, separator of dust and water and dust transfer equipment to a storage of waste. This system would be expected to have better performance and lower operating cost in decommissioning nuclear reactors, especially, the number of dust filters, for example, HEPA filters, will be considerably saved

  14. Simulation of a flowing bed kiln for the production of uranium tetrafluoride; Simulation d'un four a lit coulant pour la production de tetrafluorure d'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Dussoubs, B.; Patisson, F.; Ablitzer, D. [Ecole des Mines de Nancy, Lab. de Science et Genie des Materiaux et de Metallurgie, UMR 7584, 54 (France); Jourde, J. [Comurhex, Usine de Malvesi, 11 - Narbonne (France); Houzelot, J.L. [Ecole Nationale Superieure des Industries Chimiques (ENSIC), UPR 6811, 54 - Villers-les-Nancy (France)

    2001-07-01

    A flowing bed kiln is a gas-solid reactor used in the civil nuclear fuel cycle for the successive conversion of uranium trioxide (UO{sub 3}) into uranium dioxide (UO{sub 2}) and then into uranium tetrafluoride (UF{sub 4}). A numerical model is developed which simulate the behaviour of this reactor in permanent regime. This model describes the physico-chemical phenomena involved, and combines a mechanistic approach in the vertical area of the kiln (resolution by the finite volumes method) and a systemic approach in the horizontal area, like in the model of cascade mixers. The first results have been obtained for reference operating conditions of the industrial kiln. Some possible improvements of the optimum temperature progression inside the kiln are evoked. (J.S.)

  15. Instrumentation and measurements of temperatures of a load of bricks in a tunnel kiln using natural gas; Instrumentacao e medicao de temperaturas em uma carga de tijolos no interior de um forno tunel a gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Jahn, T.G.; Lehmkuhl, W.A.; Hartke, Rafael Fernando; Dadam, A.P.; Nicolau, V.P. [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil)

    2004-07-01

    The analysis of the thermal efficiency of ceramics kilns, a big difficulty is the experimental determination of the temperature distribution inside the kiln load. The biggest challenge is the instrumentation, since the sensors should accompany the brick load through out the kiln, which may reach a length greater than 100 m, with their connection cables exposed to temperature greater than 300 deg C. These results are important to identify under what conditions are submitted internal layers of the brick load, to determine the best brick arrangements in cart load. This work permits a best understanding of firing cycles used in the tunnels kilns. The mathematical treatment and understanding of the data will permit to create experimental analysis tools, which should be useful in other problems. (author)

  16. Four Interstellar Dust Candidates from the Stardust Interstellar Dust Collector

    Science.gov (United States)

    Westphal, A. J.; Allen, C.; Bajt, S.; Bechtel, H. A.; Borg, J.; Brenker, F.; Bridges, J.; Brownlee, D. E.; Burchell, M.; Burghammer, M.; hide

    2011-01-01

    In January 2006, the Stardust sample return capsule returned to Earth bearing the first solid samples from a primitive solar system body, Comet 81P/Wild2, and a collector dedicated to the capture and return of contemporary interstellar dust. Both collectors were approx. 0.1 sq m in area and were composed of aerogel tiles (85% of the collecting area) and aluminum foils. The Stardust Interstellar Dust Collector (SIDC) was exposed to the interstellar dust stream for a total exposure factor of 20 sq m/day. The Stardust Interstellar Preliminary Examination (ISPE) is a consortium-based project to characterize the collection using nondestructive techniques. The goals and restrictions of the ISPE are described . A summary of analytical techniques is described.

  17. Cosmic dust investigations. Pt. 2

    International Nuclear Information System (INIS)

    Simpson, J.A.; Tuzzolino, A.J.

    1989-01-01

    A series of experiments have been completed using accelerator dust particles in the mass range ≅ 10 -9 -10 -6 g and velocity range ≅ 2-12 km/s to measure the velocity loss and degree of fragmentation for dust particles penetrating 6 and 28 μm thick polyvinylidene fluoride (PVDF) dust detectors. These measurements prove that even for a ratio of PVDF foil thickness to particle diameter as large as 0.6, the velocity loss and fragmentation is far less than expected from earlier reports in the literature. For 6 μm thick foils the velocity loss is ≤5%. These experiments are based on an extension of our earlier work which showed that two PVDF foils spaced a given distance apart could provide accurate time-of-flight (TOF) information due to the fast pulse rise time of PVDF detector response. We also report on our present state of development of PVDF position-sensing detectors which identify the x, y coordinates of particle impact, using detector and electronic pulse techniques adapted from our semiconductor position-sensing cosmic-ray detectors. Typical position errors of ≅ 1 mm are readily achieved. Finally, we have combined the above developments into a dust-particle telescope which accurately (≅ 1 0 angular accuracy) measures the trajectory of the incident particle as well as its mass and incident velocity, irrespective of whether it is a charged or neutral particle. We discuss how this practical dust telescope can be combined with dust capture cells for space flight and later recovery for laboratory determination of elemental and isotopic composition of captured dust. We also describe a simpler trajectory array based on discrete mosaics of thin detectors which would measure trajectories with a mean angular error of ≅ 4 0 . We discuss the application of these instruments for distinguishing between interplanetary dust of cometary and asteroidal origin, and for measurements on a space station, from near-Earth trapped dust of artificial origin. (orig.)

  18. Charged dust in saturn's magnetosphere

    International Nuclear Information System (INIS)

    Mendis, D.A.; Hill, J.R.; Houpis, H.L.F.

    1983-01-01

    Gravito-electrodynamic theory of charged dust grains is used to explain a variety of phenomena in those portions of the Saturnian ring system that are known to be dominated by fine (micron- and submicron-sized) dust, and in which collisional forces and Coulomb drag can be neglected. Among the phenomena discussed are the formation and evolution of the rotating near-radial spokes in the B-ring, the formation of waves in the F-ring, the cause of eccentricities of certain isolated ringlets, and the origin and morphology of the broad diffuse E-ring. Several novel processes predicted by the gravitoelectrodynamic theory, including 'magneto-gravitational capture' of exogenic dust by the magnetosphere, '1:1 magneto-gravitational orbital resonances' of charged dust with nearby satellites, and 'gyro-orbital resonances,' are used to explain individual observations. The effect of a ring current associated with this charged dust is also evaluated. Finally, the cosmogonic implications of the magneto-gravitational theory are briefly discussed. While several (although not all) of these processes have been discussed by one or more of the present authors elsewhere, the purpose of this paper is to synthesize all these processes within the framework of gravito-electrodynamics, and also to show its range of applicability within Saturn's ring system

  19. Spring Dust Storm Smothers Beijing

    Science.gov (United States)

    2002-01-01

    A few days earlier than usual, a large, dense plume of dust blew southward and eastward from the desert plains of Mongolia-quite smothering to the residents of Beijing. Citizens of northeastern China call this annual event the 'shachenbao,' or 'dust cloud tempest.' However, the tempest normally occurs during the spring time. The dust storm hit Beijing on Friday night, March 15, and began coating everything with a fine, pale brown layer of grit. The region is quite dry; a problem some believe has been exacerbated by decades of deforestation. According to Chinese government estimates, roughly 1 million tons of desert dust and sand blow into Beijing each year. This true-color image was made using two adjacent swaths (click to see the full image) of data from the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), flying aboard the OrbView-2 satellite, on March 17, 2002. The massive dust storm (brownish pixels) can easily be distinguished from clouds (bright white pixels) as it blows across northern Japan and eastward toward the open Pacific Ocean. The black regions are gaps between SeaWiFS' viewing swaths and represent areas where no data were collected. Image courtesy the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE

  20. Physical properties of five grain dust types.

    Science.gov (United States)

    Parnell, C B; Jones, D D; Rutherford, R D; Goforth, K J

    1986-01-01

    Physical properties of grain dust derived from five grain types (soybean, rice, corn, wheat, and sorghum) were measured and reported. The grain dusts were obtained from dust collection systems of terminal grain handling facilities and were assumed to be representative of grain dust generated during the handling process. The physical properties reported were as follows: particle size distributions and surface area measurements using a Coulter Counter Model TAII; percent dust fractions less than 100 micron of whole dust; bulk density; particle density; and ash content. PMID:3709482

  1. Design and testing of a roller kiln for ceramic tile manufacturing with lower environmental impact and higher performance; Conception et essai d'un four a rouleaux pour carreaux a impact environnemental faible et performances elevees

    Energy Technology Data Exchange (ETDEWEB)

    Reimer, A. [DPD-TNO, Delft (Netherlands); Bresciani, A.; Pifferi, G. [SACMI, Savoyarde de Construction de Materiel Industriel, 73 - Montmelian (France)

    1999-09-01

    Motivated by the need to improve firing processes of ceramic tiles with regard to either the homogeneity of the heat distribution in the kiln section or the harmful emissions (particularly fluoride), TNO and the Dutch tile industry, in cooperation with SACMI, have developed a new kiln concept. The study has led to designing and manufacturing a prototype roller kiln, that will be started up and tested at the MOSA facilities in Maastricht. Other partners include SPHINX GUSTAVSBERG, GASUNIE, GOUDA VUURVAST and the Dutch government as sponsor. Great attention has been devoted to control the temperature distribution inside the kiln as well as to manage the fast firing cycles currently used. Burner power, positions, flow, emission level have been calculated using the TNO kiln simulation models. New, but commercially available technologies have been integrated into the new kiln engineering, thus to improve the firing process, reduce emissions and minimize energy consumption. The main technological solutions applied are: (1)radiant tube burners in the firing zone (2)new convective burners in the heating zone (3)convection enhancement in the pre-heating zone by adopting adequate systems for the recirculation of fumes.

  2. Glass Frit Clumping And Dusting

    International Nuclear Information System (INIS)

    Steimke, J. L.

    2013-01-01

    DWPF mixes a slurry of glass frit (Frit 418) and dilute (1.5 wt%) formic acid solution with high level waste in the Slurry Mix Evaporator (SME). There would be advantages to introducing the frit in a non-slurry form to minimize water addition to the SME, however, adding completely dry frit has the potential to generate dust which could clog filters or condensers. Prior testing with another type of frit, Frit 320, and using a minimal amount of water reduced dust generation, however, the formation of hard clumps was observed. To examine options and behavior, a TTQAP [McCabe and Stone, 2013] was written to initiate tests that would address these concerns. Tests were conducted with four types of glass frit; Frit 320, DWPF Frit 418, Bekeson Frit 418 and Multi-Aspirator Frit 418. The last two frits are chemically identical to DWPF Frit 418 but smaller particles were removed by the respective vendors. Test results on Frit Clumping and Dusting are provided in this report. This report addresses the following seven questions. Short answers are provided below with more detailed answers to follow. 1. Will the addition of a small amount of water, 1.5 wt%, to dry DWPF Frit 418 greatly reduce the dust generation during handling at DWPF? a. Yes, a small scale test showed that adding a little water to the frit greatly reduced dust generation during handling. 2. Will the addition of small amounts of water to the frit cause clumping that will impair frit handling at DWPF? a. No, not with Frit 418. Although clumps were observed to form when 1.5 wt% water was mixed with DWPF Frit 418, then compressed and air-dried overnight, the clumps were easily crushed and did not form the hardened material noted when Frit 320 was tested. 3. What is the measured size distribution of dust generated when dry frit is handled? (This affects the feasibility and choice of processing equipment for removing the dust generating fraction of the frit before it is added to the SME.) a. The size distribution for

  3. Glass Frit Clumping And Dusting

    Energy Technology Data Exchange (ETDEWEB)

    Steimke, J. L.

    2013-09-26

    DWPF mixes a slurry of glass frit (Frit 418) and dilute (1.5 wt%) formic acid solution with high level waste in the Slurry Mix Evaporator (SME). There would be advantages to introducing the frit in a non-slurry form to minimize water addition to the SME, however, adding completely dry frit has the potential to generate dust which could clog filters or condensers. Prior testing with another type of frit, Frit 320, and using a minimal amount of water reduced dust generation, however, the formation of hard clumps was observed. To examine options and behavior, a TTQAP [McCabe and Stone, 2013] was written to initiate tests that would address these concerns. Tests were conducted with four types of glass frit; Frit 320, DWPF Frit 418, Bekeson Frit 418 and Multi-Aspirator Frit 418. The last two frits are chemically identical to DWPF Frit 418 but smaller particles were removed by the respective vendors. Test results on Frit Clumping and Dusting are provided in this report. This report addresses the following seven questions. Short answers are provided below with more detailed answers to follow. 1. Will the addition of a small amount of water, 1.5 wt%, to dry DWPF Frit 418 greatly reduce the dust generation during handling at DWPF? a. Yes, a small scale test showed that adding a little water to the frit greatly reduced dust generation during handling. 2. Will the addition of small amounts of water to the frit cause clumping that will impair frit handling at DWPF? a. No, not with Frit 418. Although clumps were observed to form when 1.5 wt% water was mixed with DWPF Frit 418, then compressed and air-dried overnight, the clumps were easily crushed and did not form the hardened material noted when Frit 320 was tested. 3. What is the measured size distribution of dust generated when dry frit is handled? (This affects the feasibility and choice of processing equipment for removing the dust generating fraction of the frit before it is added to the SME.) a. The size distribution for

  4. Dust deposit in recirculation regions

    International Nuclear Information System (INIS)

    Griemert, R.

    1985-03-01

    The present report shows investigations, which have been carried out in a closed duct at forward and backward facing steps. Distribution of fluid velocity and fluid fluctuations in and normal to main flow direction as well as the distribution of Reynolds shear stress have been measured. The mass transfer downstream of a backward facing step has been investigated as well. By using graphite-, copper-, tin- and rubber dust, conditions of deposition have been defined experimentally. A serie of photos shows the filling of a recirculation region downstream of a backward facing step with graphite dust. The present investigations allow to avoid deposition of dust in recirculation regions by selecting the fluid numbers in an appropriate way. (orig.) [de

  5. Dust Storm Hits Canary Islands

    Science.gov (United States)

    2002-01-01

    A thick pall of sand and dust blew out from the Sahara Desert over the Atlantic Ocean yesterday (January 6, 2002), engulfing the Canary Islands in what has become one of the worst sand storms ever recorded there. In this scene, notice how the dust appears particularly thick in the downwind wake of Tenerife, the largest of the Canary Islands. Perhaps the turbulence generated by the air currents flowing past the island's volcanic peaks is churning the dust back up into the atmosphere, rather than allowing it to settle toward the surface. This true-color image was captured by the Moderate-resolution Imaging Spectroradiometer (MODIS), flying aboard NASA's Terra satellite, on January 7, 2002. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  6. Mechanisms of metal dusting corrosion

    DEFF Research Database (Denmark)

    Hummelshøj, Thomas Strabo

    In this thesis the early stages of metal dusting corrosion is addressed; the development of carbon expanded austenite, C, and the decomposition hereof into carbides. Later stages of metal dusting corrosion are explored by a systematic study of stainless steel foils exposed to metal dusting...... deformed stainless steel flakes is transformed to expanded martensite/austenite during low-temperature carburization. Various experimental procedures to experimentally determine the concentration dependent diffusion coefficient of carbon in expanded austenite are evaluated. The most promising procedure...... powders and flakes. The nature of the decomposition products, carbides of the form M23C6 and M7C3, were evaluated by X-ray diffraction, light optical microscopy, scanning electron microscopy and thermodynamic modelling. The decomposition was found to be dependent on several parameters such as thermal...

  7. Intergalactic dust and quasar distribution

    International Nuclear Information System (INIS)

    Soltan, A.

    1979-01-01

    Non-homogeneous intergalactic extinction may considerably affect the quasar distribution. Especially samples of quasars isolated on the basis of B-V colours are subject to this phenomenon. Apparent grouping and close pairs of quasars reported in the literature may be a result of intergalactic dust. Using surface distribution of faint blue objects selected by Hawkins and Reddish it is estimated that intergalactic extinction in B should reach approximately 1 mag out to the redshift of approximately 1. This is slightly larger than predicted by theory and comparable to the mean dust density derived from observations. (Author)

  8. The distribution of interstellar dust

    International Nuclear Information System (INIS)

    Clocchiatti, A.; Marraco, H.G.

    1986-01-01

    We propose the interstellar matter structural function as a tool to derive the features of the interstellar dust distribution. We study that function resolving some ideal dust distribution models. Later we describe the method used to find a reliable computing algorithm for the observational case. Finally, we describe the steps to build a model for the interstellar matter composed by spherically symmetrical clouds. The density distribution for each of these clouds is D(r) = D 0 .esup(-r/r 0 ) 2 . The preliminary results obtained are summarised. (author)

  9. Determination of fluorine injuries on an alley of linden trees in the immediate proximity of a brick kiln near Ismaning by leaf analysis and aerial infrared photography

    Energy Technology Data Exchange (ETDEWEB)

    Baum, I F

    1974-01-01

    Upon discovery of severe leaf injuries in an alley of linden trees near Ismaning (Munich, West Germany), leaf samples were taken from the lower branches of the trees at three different time periods. The samples were dried, ground, and ashed according to the method by Buck (ashing of 5 g dry substance in a nickel vessel at a temperature of 450 to 500 C in a muffle furnace). The fluorine in the ash was determined by the method of Buck and Stratman. A relationship was determined between the fluorine concentration of the leaves and the location of the tree with regard to a brick kiln close to the alley. The severity of necrosis not only corresponded to the determined fluorine concentration but also the gray tone of the infrared photographs. The results led to the initiation of measures for reduction of the fluorine emissions by this brick kiln. 17 references.

  10. Electrostatic Dust Detector with Improved Sensitivity

    International Nuclear Information System (INIS)

    Boyle, D.P.; Skinner, C.H.; Roquemore, A.L.

    2008-01-01

    Methods to measure the inventory of dust particles and to remove dust if it approaches safety limits will be required in next-step tokamaks such as ITER. An electrostatic dust detector, based on a fine grid of interlocking circuit traces, biased to 30 or 50 V, has been developed for the detection of dust on remote surfaces in air and vacuum environments. Gaining operational experience of dust detection on surfaces in tokamaks is important, however the level of dust generated in contemporary short-pulse tokamaks is comparatively low and high sensitivity is necessary to measure dust on a shot-by-shot basis. We report on modifications in the detection electronics that have increased the sensitivity of the electrostatic dust detector by a factor of up to 120, - a level suitable for measurements on contemporary tokamaks.

  11. Infrared Observations of Cometary Dust and Nuclei

    Science.gov (United States)

    Lisse, Carey

    2004-01-01

    This bibliography lists citations for publications published under the grant. Subjects of the publications include cometary dust, instellar and interplanetary dust, comet nuclei and comae, Comet Hale-Bopp, infrared observations of comets, mass loss, and comet break-up.

  12. The global distribution of mineral dust

    International Nuclear Information System (INIS)

    Tegen, I; Schepanski, K

    2009-01-01

    Dust aerosol particles produced by wind erosion in arid and semi arid regions affect climate and air quality, but the magnitude of these effects is largely unquantified. The major dust source regions include the Sahara, the Arabian and Asian deserts; global annual dust emissions are currently estimated to range between 1000 and 3000 Mt/yr. Dust aerosol can be transported over long distances of thousands of kilometers, e.g. from source regions in the Saharan desert over the North Atlantic, or from the Asian deserts towards the Pacific Ocean. The atmospheric dust load varies considerably on different timescales. While dust aerosol distribution and dust effects are important on global scales, they strongly depend on dust emissions that are controlled on small spatial and temporal scales.

  13. Archeointensity study on baked clay samples taken from the reconstructed ancient kiln: implication for validity of the Tsunakawa-Shaw paleointensity method

    Science.gov (United States)

    Yamamoto, Yuhji; Torii, Masayuki; Natsuhara, Nobuyoshi

    2015-05-01

    In 1972, a reconstruction experiment of a kiln had been done to reproduce an excavated kiln of the seventh century in Japan. Baked clay samples were taken from the floor surface and -20 cm level, and they have been stored after determinations of the paleomagnetic directions by partial alternating field demagnetizations. We recently applied the Tsunakawa-Shaw method to the samples to assess how reliable archeointensity results are obtained from the samples. A suite of the rock magnetic experiments and the scanning electron microscope observations elucidate that dominant magnetic carriers of the floor surface samples are Ti-poor titanomagnetite grains in approximately 10 nm size with single-domain and/or super-paramagnetic states, whereas contributions of multi-domain grains seem to be relatively large for the -20-cm level samples. From the floor surface samples, six out of the eight successful results were obtained and they give an average of 47.3 μT with a standard deviation of 2.2 μT. This is fairly consistent with the in situ geomagnetic field of 46.4 μT at the time of the reconstruction. They are obtained with a built-in anisotropy correction using anhysteretic remanent magnetization and without any cooling rate corrections. In contrast, only one out of four was successful from the -20-cm level samples. It yields an archeointensity of 31.6 μT, which is inconsistent with the in situ geomagnetic field. Considering from the in situ temperature record during the firing of the kiln and the unblocking temperature spectra of the samples, the floor surface samples acquired full thermoremanent magnetizations (TRMs) as their natural remanent magnetizations whereas the -20-cm level samples only acquired partial TRMs, and these differences probably cause the difference in the archeointensity results between the two sample groups. For archeointensity researches, baked clay samples from a kiln floor are considered to be ideal materials.

  14. Exact solutions for rotating charged dust

    International Nuclear Information System (INIS)

    Islam, J.N.

    1984-01-01

    Earlier work by the author on rotating charged dust is summarized. An incomplete class of exact solutions for differentially rotating charged dust in Newton-Maxwell theory for the equal mass and charge case that was found earlier is completed. A new global exact solution for cylindrically symmetric differentially rotating charged dust in Newton-Maxwell theory is presented. Lastly, a new exact solution for cylindrically symmetric rigidly rotating charged dust in general relativity is given. (author)

  15. Studies of dust shells around stars

    International Nuclear Information System (INIS)

    Bedijn, P.J.

    1977-01-01

    This thesis deals with some aspects of circumstellar dust shells. This dust shell, emitting infrared radiation, is described by way of its absorptive and emissive properties as well as by the transfer of radiation through the dust shell itself. Model calculations are compared to experimental results and agree reasonably well. The author also discusses the dynamics of the extended shells of gas and dust around newly formed stars

  16. First evidence of lime burning in southern Scandinavia: lime kilns found at the royal residence on the west bank of Lake Tissø

    DEFF Research Database (Denmark)

    Henriksen, Peter Steen; Holst, Sandie

    2015-01-01

    In connection with investigations of the aristocratic residence at Tissø from the Viking Age, the earliest evidence so far of lime burning in Denmark has been excavated. The excavations unearthed traces of up to five lime kilns which were subsequently dated to the end of the ninth century....... This corresponds well with the dating of the erection of the hall in the third construction phase at Fugledegård. Finds of mud-and-wattle with whitewashing show that the lime was used to whitewash the halls at Tissø in both the Germanic Iron Age and the Viking Age. Analyses of lime from the lime kilns...... and the whitewashed mud-and-wattle demonstrate that the raw material for the lime burning was mainly travertine deposited in spring water, but that bryozoan limestone was also used. The lime kilns were just under 2 m in diameter with stone-built edges, and there are indications that the superstructure may have been...

  17. Charging-discharging characteristics of macro-encapsulated phase change materials in an active thermal energy storage system for a solar drying kiln

    Directory of Open Access Journals (Sweden)

    Kumar Shailendra

    2017-01-01

    Full Text Available The present study explores suitability of two phase change materials (PCM for development of an active thermal storage system for a solar drying kiln by studying their melting and solidification behaviors. A double glass glazing prototype solar kiln was used in the study. The storage system consisted of a water storage tank with PCM placed inside the water in high density polyethylene containers. The water in the tank was heated with help of solar energy using an evacuated tube collector array. The melting and solidification temperature curves of PCM were obtained by charging and discharging the water tank. The study illustrated the utility of the PCM in using the stored thermal energy during their discharge to enhance the temperature inside the kiln. The rate of temperature reduction was found to be higher for paraffin wax as compared to a fatty acid based PCM. The water temperature during the discharge of the PCM showed dependence on the discharge characteristics of each PCM suggesting their suitability in designing active thermal storage systems.

  18. Case study of an MBT plant producing SRF for cement kiln co-combustion, coupled with a bioreactor landfill for process residues.

    Science.gov (United States)

    Grosso, Mario; Dellavedova, Stefano; Rigamonti, Lucia; Scotti, Sergio

    2016-01-01

    The paper describes the performances of the energy recovery pathway from the residual waste based on the production of a Solid Recovered Fuel (SRF) to be exploited via co-combustion in a cement kiln. The SRF is produced in a single stream Mechanical-Biological Treatment plant, where bio-drying of the waste is followed by mechanical refining in order to fulfil the quality requirements by the cement kilns. Peculiar of this MBT is the fact that sorting residues are disposed in a nearby landfill, managed according to a bioreactor approach, where landfill gas is collected for electric energy recovery. A detailed mass and energy balance of the system is presented based on one year operational data, followed by its Life Cycle Assessment. Results show that the system is energetically and environmentally effective, with most of the impacts being more than compensated by the savings of materials and energy. Major role in determining such outcome is the displacement of petcoke in the cement kiln, both in terms of its fossil CO2 emissions and of its life cycle impacts, including the trans-oceanic transport. To check the robustness of the results, two sensitivity analyses are performed on the landfill gas collection efficiency and on the avoided electric energy mix. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Radio frequency discharge with dust particles

    NARCIS (Netherlands)

    Chutov, Y. I.; W. J. Goedheer,; Kravchenko, O. Y.; Zuz, V. M.; Yan, M.; Martins, R.; Ferreira, I.; Fortunato, E.; Kroesen, G.

    2000-01-01

    A 1D PIC/MCC method has been developed for computer simulations of low-pressure RF discharges with dust particles using the method for dust-free discharges. A RF discharge in argon with dust particles distributed uniformly in the interelectrode gap is simulated at parameters providing a possibility

  20. Thirteen years of Aeolian dust dynamics in a desert region (Negev desert, Israel): analysis of horizontal and vertical dust flux, vertical dust distribution and dust grain size

    NARCIS (Netherlands)

    Offer, Z.Y.; Goossens, D.

    2004-01-01

    At Sede Boqer (northern Negev desert, Israel), aeolian dust dynamics have been measured during the period 1988–2000. This study focuses on temporal records of the vertical and horizontal dust flux, the vertical distribution of the dust particles in the atmosphere, and the grain size of the

  1. Dust Measurements Onboard the Deep Space Gateway

    Science.gov (United States)

    Horanyi, M.; Kempf, S.; Malaspina, D.; Poppe, A.; Srama, R.; Sternovsky, Z.; Szalay, J.

    2018-02-01

    A dust instrument onboard the Deep Space Gateway will revolutionize our understanding of the dust environment at 1 AU, help our understanding of the evolution of the solar system, and improve dust hazard models for the safety of crewed and robotic missions.

  2. Properties of interstellar dust in reflection nebulae

    International Nuclear Information System (INIS)

    Sellgren, K.

    1988-01-01

    Observations of interstellar dust in reflection nebulae are the closest analog in the interstellar medium to studies of cometary dust in our solar system. The presence of a bright star near the reflection nebula dust provides the opportunity to study both the reflection and emission characteristics of interstellar dust. At 0.1 to 1 micrometer, the reflection nebula emission is due to starlight scattered by dust. The albedo and scattering phase function of the dust is determined from observations of the scattered light. At 50 to 200 micrometers, thermal emission from the dust in equilibrium with the stellar radiation field is observed. The derived dust temperature determines the relative values of the absorption coefficient of the dust at wavelengths where the stellar energy is absorbed and at far infrared wavelengths where the absorbed energy is reradiated. These emission mechanisms directly relate to those seen in the near and mid infrared spectra of comets. In a reflection nebula the dust is observed at much larger distances from the star than in our solar system, so that the equilibrium dust temperature is 50 K rather than 300 K. Thus, in reflection nebulae, thermal emission from dust is emitted at 50 to 200 micrometer

  3. House dust extracts contain potent immunological adjuvants

    NARCIS (Netherlands)

    Beukelman, C.J.; Dijk, H. van; Aerts, P.C.; Rademaker, P.M.; Berrens, L.; Willers, J.M.N.

    1987-01-01

    A crude aqueous extract of house dust and two house dust subfractions were tested for adjuvant activity in a sensitivity assay performed in mice. Evidence is presented that house dust contains at least two potent immunological adjuvants. One of these, present in both subfractions, was probably

  4. Observed spectral features of dust

    International Nuclear Information System (INIS)

    Willner, S.P.

    1984-01-01

    The author concentrates on the observed properties of dust spectral features. Identifications, based on laboratory data, are given whenever plausible ones exist. There are a very large number of papers in the literature of even such a young field as infrared spectroscopy, and therefore the author refers only to the most recent paper on a topic or to another review. (Auth.)

  5. Meteors, meteorites and cosmic dust

    International Nuclear Information System (INIS)

    Lebedinets, V.N.

    1987-01-01

    The problem of meteorite origin and meteorite composition is discussed. Nowadays, most scientists suppose that the giant Oort cloud consisting of ice comet nuclei is the sourse of the meteor matter. A principle unity of the matter of meteorites falling to the Earth and cosmic dust is noted as well as that of meteorite bodies evaporating in the atmosphere and bearing meteors and bodies

  6. Occupational diseases of dust etiology

    International Nuclear Information System (INIS)

    Sokolik, L.I.; Shkondin, A.N.

    1981-01-01

    Detailed etiologic and clinico-roentgenological characteristics of pneumoconiosis, as widely spread occupational disease caused by different kinds of dust, are given. The course of pneumoconiosis is discussed depending on working conditions of patients after the disease had been ascertained, as well as its complications, taking into account roentgeno-morphological types of fibrosis and the stages of the disease [ru

  7. 75 FR 32142 - Combustible Dust

    Science.gov (United States)

    2010-06-07

    .... Contact Mat Chibbaro, P.E., Fire Protection Engineer, Office of Safety Systems, OSHA Directorate of..., and metals (such as aluminum and magnesium). Industries that may have combustible dust hazards include..., chemical manufacturing, textile manufacturing, furniture manufacturing, metal processing, fabricated metal...

  8. Residence-Time Distributions in Laminar Flows and During the Passage of Granular Solids Through Rotary Kilns

    Energy Technology Data Exchange (ETDEWEB)

    Beek, W. J.; De Ridder, H. J. [Technische Hogeschool, Delft (Netherlands); Houtman, J. P.W.; Kuiper, D. [Reactor Instituut, Delft (Netherlands)

    1967-06-15

    Data on residence-time distributions are important in the design of apparatus for the chemical industry. Radioactive tracers can be useful in many cases, e.g. where a pulse technique is desired. Two examples are given in which a pulse of radioactive tracer is used. The first example deals with the residence-time distribution of a laminar, Newtonian flow in an annulus. This problem arises especially in the extrusion and injection moulding of polymers and in the coating of wires with plastics. In these cases the fractions of polymer with long residence times may have other properties than the polymer that flows fastest, because the polymerization reaction or the degradation reactions go on during the process. Two difficulties are to be considered: (a) the tracer pulse (a radioactive Au-sol suspended in the liquid used) cannot be distributed over the cross-section in proportion to the local flow velocity, and (b) the outflowing liquid must be sampled discontinuously. Both effects have been studied and corrections are indicated. When these corrections are applied to the measured distribution curve, the result is in fair agreement with the calculated residence-time distribution. The second example considers the residence-time distribution in a granular solid (sand) passing through a rotary kiln. The response was measured at the outlet to a pulse at the inlet of radioactive material (sand impregnated with a solution of radioactive AuCl{sub 3}). When calculating the residence-time distribution from the experimental data, difficulties were encountered because the duration of the pulse was of the same order of magnitude as the average residence time. Considering this, it was found that the axial dispersion of the flow of sand could be described by an effective dispersion coefficient. This dispersion coefficient proved to be very low (order of magnitude 10{sup -5} m{sup 2}/s); hence, in practical situations, the flow of granular material through a rotary kiln may often be

  9. Trapping Dust to Form Planets

    Science.gov (United States)

    Kohler, Susanna

    2017-10-01

    Growing a planet from a dust grain is hard work! A new study explores how vortices in protoplanetary disks can assist this process.When Dust Growth FailsTop: ALMA image of the protoplanetary disk of V1247 Orionis, with different emission components labeled. Bottom: Synthetic image constructed from the best-fit model. [Kraus et al. 2017]Gradual accretion onto a seed particle seems like a reasonable way to grow a planet from a grain of dust; after all, planetary embryos orbit within dusty protoplanetary disks, which provides them with plenty of fuel to accrete so they can grow. Theres a challenge to this picture, though: the radial drift problem.The radial drift problem acknowledges that, as growing dust grains orbit within the disk, the drag force on them continues to grow as well. For large enough dust grains perhaps around 1 millimeter the drag force will cause the grains orbits to decay, and the particles drift into the star before they are able to grow into planetesimals and planets.A Close-Up Look with ALMASo how do we overcome the radial drift problem in order to form planets? A commonly proposed mechanism is dust trapping, in which long-lived vortices in the disk trap the dust particles, preventing them from falling inwards. This allows the particles to persist for millions of years long enough to grow beyond the radial drift barrier.Observationally, these dust-trapping vortices should have signatures: we would expect to see, at millimeter wavelengths, specific bright, asymmetric structures where the trapping occurs in protoplanetary disks. Such disk structures have been difficult to spot with past instrumentation, but the Atacama Large Millimeter/submillimeter Array (ALMA) has made some new observations of the disk V1247 Orionis that might be just what were looking for.Schematic of the authors model for the disk of V1247 Orionis. [Kraus et al. 2017]Trapped in a Vortex?ALMAs observations of V1247 Orionis are reported by a team of scientists led by Stefan

  10. Cosmological simulation with dust formation and destruction

    Science.gov (United States)

    Aoyama, Shohei; Hou, Kuan-Chou; Hirashita, Hiroyuki; Nagamine, Kentaro; Shimizu, Ikkoh

    2018-06-01

    To investigate the evolution of dust in a cosmological volume, we perform hydrodynamic simulations, in which the enrichment of metals and dust is treated self-consistently with star formation and stellar feedback. We consider dust evolution driven by dust production in stellar ejecta, dust destruction by sputtering, grain growth by accretion and coagulation, and grain disruption by shattering, and treat small and large grains separately to trace the grain size distribution. After confirming that our model nicely reproduces the observed relation between dust-to-gas ratio and metallicity for nearby galaxies, we concentrate on the dust abundance over the cosmological volume in this paper. The comoving dust mass density has a peak at redshift z ˜ 1-2, coincident with the observationally suggested dustiest epoch in the Universe. In the local Universe, roughly 10 per cent of the dust is contained in the intergalactic medium (IGM), where only 1/3-1/4 of the dust survives against dust destruction by sputtering. We also show that the dust mass function is roughly reproduced at ≲ 108 M⊙, while the massive end still has a discrepancy, which indicates the necessity of stronger feedback in massive galaxies. In addition, our model broadly reproduces the observed radial profile of dust surface density in the circum-galactic medium (CGM). While our model satisfies the observational constraints for the dust extinction on cosmological scales, it predicts that the dust in the CGM and IGM is dominated by large (>0.03 μm) grains, which is in tension with the steep reddening curves observed in the CGM.

  11. Respiratory Toxicity of Lunar Highland Dust

    Science.gov (United States)

    James, John T.; Lam, Chiu-wing; Wallace, William T.

    2009-01-01

    Lunar dust exposures occurred during the Apollo missions while the crew was on the lunar surface and especially when microgravity conditions were attained during rendezvous in lunar orbit. Crews reported that the dust was irritating to the eyes and in some cases respiratory symptoms were elicited. NASA s vision for lunar exploration includes stays of 6 months on the lunar surface hence the health effects of periodic exposure to lunar dust need to be assessed. NASA has performed this assessment with a series of in vitro and in vivo tests on authentic lunar dust. Our approach is to "calibrate" the intrinsic toxicity of lunar dust by comparison to a nontoxic dust (TiO2) and a highly toxic dust (quartz) using intratrachael instillation of the dusts in mice. A battery of indices of toxicity is assessed at various time points after the instillations. Cultures of selected cells are exposed to test dusts to assess the adverse effects on the cells. Finally, chemical systems are used to assess the nature of the reactivity of various dusts and to determine the persistence of reactivity under various environmental conditions that are relevant to a space habitat. Similar systems are used to assess the dissolution of the dust. From these studies we will be able to set a defensible inhalation exposure standard for aged dust and predict whether we need a separate standard for reactive dust. Presently-available data suggest that aged lunar highland dust is slightly toxic, that it can adversely affect cultured cells, and that the surface reactivity induced by grinding the dust persists for a few hours after activation.

  12. Design and development of a dust dispersion chamber to quantify the dispersibility of rock dust.

    Science.gov (United States)

    Perera, Inoka E; Sapko, Michael J; Harris, Marcia L; Zlochower, Isaac A; Weiss, Eric S

    2016-01-01

    Dispersible rock dust must be applied to the surfaces of entries in underground coal mines in order to inert the coal dust entrained or made airborne during an explosion and prevent propagating explosions. 30 CFR. 75.2 states that "… [rock dust particles] when wetted and dried will not cohere to form a cake which will not be dispersed into separate particles by a light blast of air …" However, a proper definition or quantification of "light blast of air" is not provided. The National Institute for Occupational Safety and Health (NIOSH) has, consequently, designed a dust dispersion chamber to conduct quantitative laboratory-scale dispersibility experiments as a screening tool for candidate rock dusts. A reproducible pulse of air is injected into the chamber and across a shallow tray of rock dust. The dust dispersed and carried downwind is monitored. The mass loss of the dust tray and the airborne dust measurements determine the relative dispersibility of the dust with respect to a Reference rock dust. This report describes the design and the methodology to evaluate the relative dispersibility of rock dusts with and without anti-caking agents. Further, the results of this study indicate that the dispersibility of rock dusts varies with particle size, type of anti-caking agent used, and with the untapped bulk density. Untreated rock dusts, when wetted and dried forming a cake that was much less dispersible than the reference rock dust used in supporting the 80% total incombustible content rule.

  13. Utilizing TEMPO surface estimates to determine changes in emissions, community exposure and environmental impacts from cement kilns across North America using alternative fuels

    Science.gov (United States)

    Pegg, M. J.; Gibson, M. D.; Asamany, E.

    2015-12-01

    A major problem faced by all North American (NA) Governments is managing solid waste from residential and non-residential sources. One way to mitigate the need to expand landfill sites across NA is waste diversion for use as alternative fuel in industries such as cement manufacture. Currently, waste plastic, tires, waste shingles and other high carbon content waste destined for landfill are being explored, or currently used, as an alternative supplemental fuels for use in cement kilns across NA. While this is an attractive, environmentally sustainable solution, significant knowledge gaps remain in our fundamental understanding of whether these alternative fuels may lead to increased air pollution emissions from cement kilns across NA. The long-term objective of using TEMPO is to advance fundamental understanding of uncharacterized air pollution emissions and to assess the actual or potential environmental and health impacts of these emissions from cement kilns across NA. TEMPO measurements will be made in concert with in-situ observations augmented by air dispersion, land-use regression and receptor modelling. This application of TEMPO follows on from current research on a series of bench scale and pilot studies for Lafarge Canada Inc., that investigated the change in combustion emissions from various mixtures of coal (C), petroleum coke (PC) and non-recyclable alternative fuels. From our work we demonstrated that using an alternative fuel mixture in a cement kiln has potential to reduce emissions of CO2 by 34%; reduce NOx by 80%, and reduce fuel SO2 emissions by 98%. We also provided evidence that there would be a significant reduction in the formation of secondary ground-level ozone (O3) and secondary PM2.5 in downwind stack plumes if alternative waste derived fuels are used. The application of air dispersion, source apportionment, land use regression; together with remote sensing offers a powerful set of tools with the potential to improve air pollution

  14. Step by step in dust control

    Energy Technology Data Exchange (ETDEWEB)

    Archer, N. [Arch Environmental Equipment, Inc. (United States)

    2003-05-01

    The paper examines the different stages in identifying delegating and controlling dust before it becomes a serious problem for a facility. Material handling, processing, storage and traffic are the major dust producing sources. All industries that convey dry, light material need to install a dust control system. The confine-seal-suppress method of dust control has provided excellent results in numerous applications, only with the combination of all three will maximum dust control. When a system is properly engineered and correctly installed, meeting the EPA Government standards becomes very easy, and is necessary in to the operation of a quality facility. 5 photos.

  15. Dust bands in the asteroid belt

    International Nuclear Information System (INIS)

    Sykes, M.V.; Greenberg, R.; Dermott, S.F.; Nicholson, P.D.; Burns, J.A.

    1989-01-01

    This paper describes the original IRAS observations leading to the discovery of the three dust bands in the asteroid belt and the analysis of data. Special attention is given to an analytical model of the dust band torus and to theories concerning the origin of the dust bands, with special attention given to the collisional equilibrium (asteroid family), the nonequilibrium (random collision), and the comet hypotheses of dust-band origin. It is noted that neither the equilibrium nor nonequilibrium models, as currently formulated, present a complete picture of the IRAS dust-band observations. 32 refs

  16. Linear Alkylbenzenesulfonates in indoor Floor Dust

    DEFF Research Database (Denmark)

    Madsen, Jørgen Øgaard; Wolkoff, Peder; Madsen, Jørgen Øgaard

    1999-01-01

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

  17. Time-Dependent Dust Formation in Novae

    Directory of Open Access Journals (Sweden)

    Kyung-Won Suh

    1991-06-01

    Full Text Available The dust formation processes in novae are investigated with close attention to recent infrared observations. Using mainly the classical nucleation theory, we have calculated the time scales of dust formation and growth in the environments of novae. Those time scales roughly resemble the typical observations. We have classified the dust-forming novae into three classes according to their explosion properties and the thermodynamic properties of dust grains. Oxygen grains from much later than carbon grains because of their thermodynamic properties. The effect of grain formation to the efficiency of stellar winds to drive the material outward is tested with newly obtained Planck mean values of dust grains.

  18. Numerical Prediction of Dust. Chapter 10

    Science.gov (United States)

    Benedetti, Angela; Baldasano, J. M.; Basart, S.; Benincasa, F.; Boucher, O.; Brooks, M.; Chen, J. P.; Colarco, P. R.; Gong, S.; Huneeus, N.; hide

    2013-01-01

    Covers the whole breadth of mineral dust research, from a scientific perspective Presents interdisciplinary work including results from field campaigns, satellite observations, laboratory studies, computer modelling and theoretical studies Explores the role of dust as a player and recorder of environmental change This volume presents state-of-the-art research about mineral dust, including results from field campaigns, satellite observations, laboratory studies, computer modelling and theoretical studies. Dust research is a new, dynamic and fast-growing area of science and due to its multiple roles in the Earth system, dust has become a fascinating topic for many scientific disciplines. Aspects of dust research covered in this book reach from timescales of minutes (as with dust devils, cloud processes, and radiation) to millennia (as with loess formation and oceanic sediments), making dust both a player and recorder of environmental change. The book is structured in four main parts that explore characteristics of dust, the global dust cycle, impacts of dust on the Earth system, and dust as a climate indicator. The chapters in these parts provide a comprehensive, detailed overview of this highly interdisciplinary subject. The contributions presented here cover dust from source to sink and describe all the processes dust particles undergo while travelling through the atmosphere. Chapters explore how dust is lifted and transported, how it affects radiation, clouds, regional circulations, precipitation and chemical processes in the atmosphere, and how it deteriorates air quality. The book explores how dust is removed from the atmosphere by gravitational settling, turbulence or precipitation, how iron contained in dust fertilizes terrestrial and marine ecosystems, and about the role that dust plays in human health. We learn how dust is observed, simulated using computer models and forecast. The book also details the role of dust deposits for climate reconstructions

  19. Dust removal system for fusion experimental reactors

    International Nuclear Information System (INIS)

    Onozuka, M.; Ueda, Y.; Takahashi, K.; Oda, Y.; Seki, Y.; Ueda, S.; Aoki, I.

    1995-01-01

    Development of a dust removal system using static electricity has been conducted. It is envisioned that the system can collect and transport dust under vacuum. In the system, the dust is charged by dielectric polarization and floated by an electrostatic attraction force that is generated by the DC electric field. The dust is then transported by the electric curtain formed by the three-phase AC electric field. Experimental investigation has been conducted to examine the characteristics of the system. Current research results indicate that the dust removal system using static electricity can be used for fusion experimental reactors

  20. Dust removal system for fusion experimental reactors

    Energy Technology Data Exchange (ETDEWEB)

    Onozuka, M.; Ueda, Y.; Takahashi, K.; Oda, Y. [Mitsubishi Heavy Industries, Ltd., Yokohama (Japan); Seki, Y.; Ueda, S.; Aoki, I. [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan)

    1995-12-31

    Development of a dust removal system using static electricity has been conducted. It is envisioned that the system can collect and transport dust under vacuum. In the system, the dust is charged by dielectric polarization and floated by an electrostatic attraction force that is generated by the DC electric field. The dust is then transported by the electric curtain formed by the three-phase AC electric field. Experimental investigation has been conducted to examine the characteristics of the system. Current research results indicate that the dust removal system using static electricity can be used for fusion experimental reactors.

  1. ORIGIN OF DUST AROUND V1309 SCO

    International Nuclear Information System (INIS)

    Zhu, Chunhua; Lü, Guoliang; Wang, Zhaojun

    2013-01-01

    The origin of dust grains in the interstellar medium is still an unanswered problem. Nicholls et al. found the presence of a significant amount of dust around V1309 Sco, which may originate from the merger of a contact binary. We investigate the origin of dust around V1309 Sco and suggest that these dust grains are produced in the binary-merger ejecta. By means of the AGBDUST code, we estimate that ∼5.2 × 10 –4 M ☉ dust grains are produced with a radii of ∼10 –5 cm. These dust grains are mainly composed of silicate and iron grains. Because the mass of the binary merger ejecta is very small, the contribution of dust produced by binary merger ejecta to the overall dust production in the interstellar medium is negligible. However, it is important to note that the discovery of a significant amount of dust around V1309 Sco offers a direct support for the idea that common-envelope ejecta provides an ideal environment for dust formation and growth. Therefore, we confirm that common envelope ejecta can be important source of cosmic dust

  2. Engineering-scale dust control experiments

    International Nuclear Information System (INIS)

    Winberg, M.R.; Pawelko, R.J.; Jacobs, N.C.; Thompson, D.N.

    1990-12-01

    This report presents the results of engineering scale dust-control experiments relating to contamination control during handling of transuranic waste. These experiments focused on controlling dust during retrieval operations of buried waste where waste and soil are intimately mixed. Sources of dust generation during retrieval operations include digging, dumping, and vehicle traffic. Because contaminants are expected to attach to soil particles and move with the generated dust, control of the dust spread may be the key to contamination control. Dust control techniques examined in these experiments include the use of misting systems, soil fixatives, and dust suppression agents. The Dryfog Ultrasonic Misting Head, manufactured by Sonics, Incorporated, and ENTAC, an organic resin derived from tree sap manufactured by ENTAC Corporation, were tested. The results of the experiments include product performance and recommended application methods. 19 figs., 7 refs., 6 tabs

  3. COSMIC DUST AGGREGATION WITH STOCHASTIC CHARGING

    International Nuclear Information System (INIS)

    Matthews, Lorin S.; Hyde, Truell W.; Shotorban, Babak

    2013-01-01

    The coagulation of cosmic dust grains is a fundamental process which takes place in astrophysical environments, such as presolar nebulae and circumstellar and protoplanetary disks. Cosmic dust grains can become charged through interaction with their plasma environment or other processes, and the resultant electrostatic force between dust grains can strongly affect their coagulation rate. Since ions and electrons are collected on the surface of the dust grain at random time intervals, the electrical charge of a dust grain experiences stochastic fluctuations. In this study, a set of stochastic differential equations is developed to model these fluctuations over the surface of an irregularly shaped aggregate. Then, employing the data produced, the influence of the charge fluctuations on the coagulation process and the physical characteristics of the aggregates formed is examined. It is shown that dust with small charges (due to the small size of the dust grains or a tenuous plasma environment) is affected most strongly

  4. Characteristics of ammonia emission during thermal drying of lime sludge for co-combustion in cement kilns.

    Science.gov (United States)

    Liu, Wei; Xu, Jingcheng; Liu, Jia; Cao, Haihua; Huang, Xiang-Feng; Li, Guangming

    2015-01-01

    Thermal drying was used to reduce sludge moisture content before co-combustion in cement kilns. The characteristics of ammonia (NH3) emission during thermal drying of lime sludge (LS) were investigated in a laboratory-scale tubular dry furnace under different temperature and time conditions. As the temperature increased, the NH3 concentration increased in the temperature range 100-130°C, decreased in the temperature range 130-220°C and increased rapidly at >220°C. Emission of NH3 also increased as the lime dosage increased and stabilized at lime dosages>5%. In the first 60 min of drying experiments, 55% of the NH3 was released. NH3 accounted for about 67-72% of the change in total nitrogen caused by the release of nitrogen-containing volatile compounds (VCs) from the sludge. X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy revealed that the main forms of nitrogen in sludge were amides and amines. The addition of lime (CaO) could cause conversion of N-H, N-O or C-N containing compounds to NH3 during the drying process.

  5. Study on elemental features of Longquan celadon at Fengdongyan kiln site in Yuan and Ming Dynasties by EDXRF

    Energy Technology Data Exchange (ETDEWEB)

    Li, L. [Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, 19 Yu Quan Lu, Beijing 100049 (China); Feng, S.L., E-mail: fengsl@ihep.ac.cn [Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, 19 Yu Quan Lu, Beijing 100049 (China); Feng, X.Q.; Xu, Q.; Yan, L.T.; Ma, B.; Liu, L. [Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, 19 Yu Quan Lu, Beijing 100049 (China)

    2012-12-01

    The energy dispersive X-ray fluorescence (EDXRF) is used to determine the chemical compositions of Longquan celadon body and glaze at Fengdongyan kiln in Yuan and Ming Dynasties. In order to analyze the elemental features in different cultural periods, 196 typical Longquan celadon shards are selected including the Early Yuan (EY), the Middle and Late Yuan (MLY), the Early Ming (EM) and the Middle Ming (MM) periods. The results indicate that the contents of K{sub 2}O, CaO, TiO{sub 2} and Fe{sub 2}O{sub 3} for celadon body and glaze are various in different cultural periods. The b values b=RO/(RO+R{sub 2}O), RO represents for alkali-earth metal elements and R{sub 2}O stands for alkali metal elements) show that the glazes of Longquan celadon in Yuan and Ming Dynasties belong to the category of calcium-alkali glaze. The principal component analysis (PCA) exhibits that the raw materials used for body and glaze in four periods have the inheritance relation. The only difference is that the raw materials for glaze in MM period were similar to those in EM period. The producing and firing technology of Longquan celadon had reached a higher level in the Early Ming Dynasty.

  6. Coupling Mars' Dust and Water Cycles: Effects on Dust Lifting Vigor, Spatial Extent and Seasonality

    Science.gov (United States)

    Kahre, M. A.; Hollingsworth, J. L.; Haberle, R. M.; Montmessin, F.

    2012-01-01

    The dust cycle is an important component of Mars' current climate system. Airborne dust affects the radiative balance of the atmosphere, thus greatly influencing the thermal and dynamical state of the atmosphere. Dust raising events on Mars occur at spatial scales ranging from meters to planet-wide. Although the occurrence and season of large regional and global dust storms are highly variable from one year to the next, there are many features of the dust cycle that occur year after year. Generally, a low-level dust haze is maintained during northern spring and summer, while elevated levels of atmospheric dust occur during northern autumn and winter. During years without global-scale dust storms, two peaks in total dust loading were observed by MGS/TES: one peak occurred before northern winter solstice at Ls 200-240, and one peak occurred after northern winter solstice at L(sub s) 305-340. These maxima in dust loading are thought to be associated with transient eddy activity in the northern hemisphere, which has been observed to maximize pre- and post-solstice. Interactive dust cycle studies with Mars General Circulation Models (MGCMs) have included the lifting, transport, and sedimentation of radiatively active dust. Although the predicted global dust loadings from these simulations capture some aspects of the observed dust cycle, there are marked differences between the simulated and observed dust cycles. Most notably, the maximum dust loading is robustly predicted by models to occur near northern winter solstice and is due to dust lifting associated with down slope flows on the flanks of the Hellas basin. Thus far, models have had difficulty simulating the observed pre- and post- solstice peaks in dust loading. Interactive dust cycle studies typically have not included the formation of water ice clouds or their radiative effects. Water ice clouds can influence the dust cycle by scavenging dust from atmosphere and by interacting with solar and infrared radiation

  7. House Dust Mite Respiratory Allergy

    DEFF Research Database (Denmark)

    Calderón, Moisés A; Kleine-Tebbe, Jörg; Linneberg, Allan

    2015-01-01

    Although house dust mite (HDM) allergy is a major cause of respiratory allergic disease, specific diagnosis and effective treatment both present unresolved challenges. Guidelines for the treatment of allergic rhinitis and asthma are well supported in the literature, but specific evidence on the e......Although house dust mite (HDM) allergy is a major cause of respiratory allergic disease, specific diagnosis and effective treatment both present unresolved challenges. Guidelines for the treatment of allergic rhinitis and asthma are well supported in the literature, but specific evidence...... not extend beyond the end of treatment. Finally, allergen immunotherapy has a poor but improving evidence base (notably on sublingual tablets) and its benefits last after treatment ends. This review identifies needs for deeper physician knowledge on the extent and impact of HDM allergy in respiratory disease...... and therapy of HDM respiratory allergy in practice....

  8. Collisionless damping of nonlinear dust ion acoustic wave due to dust charge fluctuation

    International Nuclear Information System (INIS)

    Ghosh, Samiran; Chaudhuri, Tushar K.; Sarkar, Susmita; Khan, Manoranjan; Gupta, M.R.

    2002-01-01

    A dissipation mechanism for the damping of the nonlinear dust ion acoustic wave in a collisionless dusty plasma consisting of nonthermal electrons, ions, and variable charge dust grains has been investigated. It is shown that the collisionless damping due to dust charge fluctuation causes the nonlinear dust ion acoustic wave propagation to be described by the damped Korteweg-de Vries equation. Due to the presence of nonthermal electrons, the dust ion acoustic wave admits both positive and negative potential and it suffers less damping than the dust acoustic wave, which admits only negative potential

  9. Respiratory effects of borax dust.

    Science.gov (United States)

    Garabrant, D H; Bernstein, L; Peters, J M; Smith, T J; Wright, W E

    1985-12-01

    The relation of respiratory symptoms, pulmonary function, and abnormalities of chest radiographs to estimated exposures of borax dust has been investigated in a cross sectional study of 629 actively employed borax workers. Ninety three per cent of the eligible workers participated in the study and exposures ranged from 1.1 mg/m3 to 14.6 mg/m3. Symptoms of acute respiratory irritation such as dryness of the mouth, nose, or throat, dry cough, nose bleeds, sore throat, productive cough, shortness of breath, and chest tightness were related to exposures of 4.0 mg/m3 or more, and were infrequent at exposures of 1.1 mg/m3. Symptoms of persistent respiratory irritation meeting the definition of chronic simple bronchitis were related to exposure among non-smokers. Decrements in the FEV1 as a percentage of predicted were seen among smokers who had heavy cumulative borax exposures (greater than or equal to 80 mg/m3 years) but were not seen among less exposed smokers or among non-smokers. Radiographic abnormalities were uncommon and were not related to dust exposure. Borax dust appears to act as a simple respiratory irritant and perhaps causes small changes in the FEV1 among smokers who are heavily exposed.

  10. Dust-Tolerant Intelligent Electrical Connection System

    Science.gov (United States)

    Lewis, Mark; Dokos, Adam; Perotti, Jose; Calle, Carlos; Mueller, Robert; Bastin, Gary; Carlson, Jeffrey; Townsend, Ivan, III; Immer, Chirstopher; Medelius, Pedro

    2012-01-01

    Faults in wiring systems are a serious concern for the aerospace and aeronautic (commercial, military, and civilian) industries. Circuit failures and vehicle accidents have occurred and have been attributed to faulty wiring created by open and/or short circuits. Often, such circuit failures occur due to vibration during vehicle launch or operation. Therefore, developing non-intrusive fault-tolerant techniques is necessary to detect circuit faults and automatically route signals through alternate recovery paths while the vehicle or lunar surface systems equipment is in operation. Electrical connector concepts combining dust mitigation strategies and cable diagnostic technologies have significant application for lunar and Martian surface systems, as well as for dusty terrestrial applications. The dust-tolerant intelligent electrical connection system has several novel concepts and unique features. It combines intelligent cable diagnostics (health monitoring) and automatic circuit routing capabilities into a dust-tolerant electrical umbilical. It retrofits a clamshell protective dust cover to an existing connector for reduced gravity operation, and features a universal connector housing with three styles of dust protection: inverted cap, rotating cap, and clamshell. It uses a self-healing membrane as a dust barrier for electrical connectors where required, while also combining lotus leaf technology for applications where a dust-resistant coating providing low surface tension is needed to mitigate Van der Waals forces, thereby disallowing dust particle adhesion to connector surfaces. It also permits using a ruggedized iris mechanism with an embedded electrodynamic dust shield as a dust barrier for electrical connectors where required.

  11. Ocular toxicity of authentic lunar dust.

    Science.gov (United States)

    Meyers, Valerie E; Garcìa, Hector D; Monds, Kathryn; Cooper, Bonnie L; James, John T

    2012-07-20

    Dust exposure is a well-known occupational hazard for terrestrial workers and astronauts alike and will continue to be a concern as humankind pursues exploration and habitation of objects beyond Earth. Humankind's limited exploration experience with the Apollo Program indicates that exposure to dust will be unavoidable. Therefore, NASA must assess potential toxicity and recommend appropriate mitigation measures to ensure that explorers are adequately protected. Visual acuity is critical during exploration activities and operations aboard spacecraft. Therefore, the present research was performed to ascertain the ocular toxicity of authentic lunar dust. Small (mean particle diameter = 2.9 ± 1.0 μm), reactive lunar dust particles were produced by grinding bulk dust under ultrapure nitrogen conditions. Chemical reactivity and cytotoxicity testing were performed using the commercially available EpiOcularTM assay. Subsequent in vivo Draize testing utilized a larger size fraction of unground lunar dust that is more relevant to ocular exposures (particles lunar dust was minimally irritating. Minor irritation of the upper eyelids was noted at the 1-hour observation point, but these effects resolved within 24 hours. In addition, no corneal scratching was observed using fluorescein stain. Low-titanium mare lunar dust is minimally irritating to the eyes and is considered a nuisance dust for ocular exposure. No special precautions are recommended to protect against ocular exposures, but fully shielded goggles may be used if dust becomes a nuisance.

  12. Conversion of lime kilns from oil firing to biofuel firing: Operating experience and modelling; Konvertering av mesaugnar fraan olje- till biobraensleeldning: Drifterfarenheter och modellering

    Energy Technology Data Exchange (ETDEWEB)

    Wadsborn, Rickard; Berglin, Niklas; Richards, Tobias

    2007-12-15

    Alternative fuels and techniques affect the operation of the lime kiln and the recausticizing plant, as well as the liquor cycle. An important effect is due to the introduction of non-process elements (NPEs), e.g. potassium, phosphorus and magnesium that accumulate in the liquor and lime cycles, respectively. Temperature profile and flame stability in the kiln also tend to change, which may have effects on ring formation. Availability and maintenance requirements for different technical solutions are important for the real saving of fossil fuel that can be reached over a longer period. The project has aimed to compile experience of the type indicated above, and to develop tools that may facilitate conversion to biofuel firing. The objective has been to gain comprehensive knowledge of the biofuels that can be used for lime kiln firing and compare them, focusing on practical experience from the plants that use or have used biofuels. One goal has been to develop validated models that can be used to describe changes that occur in the lime kiln and the chemical recovery cycle when changing fuels. The primary target group for the report is people working with energy and process related tasks in the pulp industry, and those delivering fuels or system solutions to the industry. The project has comprised data collection and modelling, as well as interviews with operations managers and visits to the mills that have several years of experience with firing of biofuels to replace oil in the lime kiln. A compilation of operating experience shows that conversion to biofuel firing is fully possible with both bark and wood powder, or with fuel gas from gasification of bark or wood shavings, and that the biofuel can replace the main part of the fuel oil in the lime kiln. However, the possibility to introduce biofuels into the lime kiln varies from mill to mill, as the mill have different possibilities to handle variations in availability of the kiln and mass flows of lime. In

  13. Dust characterisation for hot gas filters

    Energy Technology Data Exchange (ETDEWEB)

    Dockter, B.; Erickson, T.; Henderson, A.; Hurley, J.; Kuehnel, V.; Katrinak, K.; Nowok, J.; O`Keefe, C.; O`Leary, E.; Swanson, M.; Watne, T. [University of North Dakota, Grand Forks, ND (United States). Energy and Environmental Research Center (UNDEERC)

    1998-03-01

    Hot gas filtration to remove particulates from the gas flow upstream of the gas turbine is critical to the development of many of the advanced coal-fired power generation technologies such as the Air Blown Gasification Cycle (ABGC), a hybrid gasification combined cycle being developed in the UK. Ceramic candle filters are considered the most promising technology for this purpose. Problems of mechanical failure and of `difficult-to-clean` dusts causing high pressure losses across the filter elements need to be solved. The project investigated the behaviour of high-temperature filter dusts, and the factors determining the ease with which they can be removed from filters. The high-temperature behaviour of dusts from both combustion and gasification systems was investigated. Dust samples were obtained from full-scale demonstration and pilot-scale plant operating around the world. Dust samples were also produced from a variety of coals, and under several different operating conditions, on UNDEERC`s pilot-scale reactor. Key factors affecting dust behaviour were examined, including: the rates of tensile strength developing in dust cakes; the thermochemical equilibria pertaining under filtration conditions; dust adhesivity on representative filter materials; and the build-up and cleaning behaviour of dusts on representative filter candles. The results obtained confirmed the importance of dust temperature, dust cake porosity, cake liquid content, and particle size distribution in determining the strength of a dust cake. An algorithm was developed to indicate the likely sticking propensity of dusts as a function of coal and sorbent composition and combustion conditions. This algorithm was incorporated into a computer package which can be used to judge the degree of difficulty in filter cleaning that can be expected to arise in a real plant based on operating parameters and coal analyzes. 6 figs.

  14. House dust in seven Danish offices

    Science.gov (United States)

    Mølhave, L.; Schneider, T.; Kjærgaard, S. K.; Larsen, L.; Norn, S.; Jørgensen, O.

    Floor dust from Danish offices was collected and analyzed. The dust was to be used in an exposure experiment. The dust was analyzed to show the composition of the dust which can be a source of airborne dust indoors. About 11 kg of dust from vacuum cleaner bags from seven Danish office buildings with about 1047 occupants (12 751 m 2) was processed according to a standardized procedure yielding 5.5 kg of processed bulk dust. The bulk dust contained 130.000-160.000 CFU g -1 microorganisms and 71.000-90.000 CFU g -1 microfungi. The content of culturable microfungi was 65-123 CFU 30 g -1 dust. The content of endotoxins ranged from 5.06-7.24 EU g -1 (1.45 ng g -1 to 1.01 ng g -1). Allergens (ng g -1) were from 147-159 (Mite), 395-746 (dog) and 103-330 (cat). The macro molecular organic compounds (the MOD-content) varied from 7.8-9.8 mg g -1. The threshold of release of histamine from basophil leukocytes provoked by the bulk dust was between 0.3 and 1.0 mg ml -1. The water content was 2% (WGT) and the organic fraction 33%. 6.5-5.9% (dry) was water soluble. The fiber content was less than 0.2-1.5% (WGT) and the desorbable VOCs was 176-319 μg g -1. Most of the VOC were aldehydes. However, softeners for plastic (DBP and DEHP) were present. The chemical composition includes human and animal skin fragments, paper fibers, glass wool, wood and textilefibers and inorganic and metal particles. The sizes ranged from 0.001-1 mm and the average specific density was 1.0 g m -3. The bulk dust was resuspended and injected into an exposure chamber. The airborne dust was sampled and analyzed to illustrate the exposures that can result from sedimented dirt and dust. The airborne dust resulting from the bulk dust reached concentrations ranging from 0.26-0.75 mg m -3 in average contained 300-170 CFU m -3. The organic fraction was from 55-70% and the water content about 2.5% (WGT). The content of the dust was compared to the similar results reported in the literature and its toxic potency is

  15. Characterization of high concentration dust generator

    International Nuclear Information System (INIS)

    Shimura, Toichiro; Yokochi, Akira

    1999-01-01

    This paper describes the development of fluidized bed type high concentration dust generator that keeps for long period dust concentration range of about 10 mg/m 3 for the study of working place monitoring system and evaluation of respirator. The generator is keeping constant powder in fluidized bed for keeping the dust concentration. It is necessary to keep constant feeding rate of powder in order to keep the quantity of dust in the fluidized bed. Our generator enables to obtain constant feeding rate by a screw feeder and by using mixed powder with fluidising particles (glass beads) before feeding. The generator produces high concentration dust of 11.3 mg/m 3 ± 1.0 mg/m 3 for about 5 hours and keeps the dust size 4.2-4.6 μm in mass median aerodynamic diameter with reasonable reproducibility. (author)

  16. Molecules and dust in Cassiopeia A

    DEFF Research Database (Denmark)

    Biscaro, Chiara; Cherchneff, Isabelle

    2016-01-01

    We study the dust evolution in the supernova remnant Cassiopeia A. We follow the processing of dust grains that formed in the Type II-b supernova ejecta by modelling the sputtering of grains. The dust is located in dense ejecta clumps that are crossed by the reverse shock. We also investigate......-rich clumps that correspond to the outermost carbon-rich ejecta zone. We consider the various dust components that form in the supernova, several reverse shock velocities and inter-clump gas temperatures, and derive grain-size distributions and masses for the dust as a function of time. Both non...... and size, and the shock velocity in the clump. A Type II-b SN forms small grains that are sputtered within the clumps and in the inter-clump medium. For Cas A, silicate grains do not survive thermal sputtering in the inter-clump medium, while alumina, silicon carbide, and carbon dust may survive...

  17. Active Dust Experiment in the Mesosphere

    International Nuclear Information System (INIS)

    Norberg, Carol; Pellinen-Wannberg, Asta

    2008-01-01

    The mesosphere stretches from an altitude of about 50 to 90 km above the Earth's surface. Meteors entering the Earth's atmosphere are believed to ablate and hence give rise to a thin layer of dust particles in the upper part of the Earth's mesosphere. It seems that the dust is most dense in a layer that lies between 80 and 90 km. The dust particles are thought to have sizes of a few to tens of nanometers. Efforts have been made to measure these particles using rockets and radar techniques with limited success. We propose to release dust into the mesosphere over northern Sweden at a height of about 90 km and observe the released dust using the EISCAT radar system. The dust will be launched from the Swedish Space Corporation Esrange Space Centre on a single-stage Improved-Orion rocket that will be launched so that its flight path will be in the radar field of view.

  18. Dust observations by PFS on Mars Express

    Science.gov (United States)

    Zasova, L. V.; Formisano, V.; Moroz, V. I.; Grassi, D.; Ignatiev, N. I.; Blecka, M. I.; Maturilli, A.; Palomba, E.; Piccioni, G.; Pfs Team

    Dust is always present in the Martian atmosphere with opacity, which changes from values below 0.1 (at 9 μ m) up to several units during the dust storms. From the thermal IR (LW channel of PFS) the dust opacity is retrieved in a self consistent way together with the temperature profile from the same spectrum A preliminary investigation along the orbit, which comes through Hellas, shows that the value of dust opacity anticorrelates with surface altitude. From -70 to +25 of latitude the vertical dust distribution follows the exponential low with the scale of 12 km, which corresponds to the gaseous scale height near noon and indicates for well mixed condition. The dust opacity, corresponding to the zero surface altitude, is found of 0.25+-0.05. More detailed investigations of all available data will be presented, including analysis of both short- and long- wavelength spectra of PFS.

  19. Formation and dissociation of dust molecules in dusty plasma

    International Nuclear Information System (INIS)

    Yan Jia; Feng Fan; Liu Fucheng; Dong Lifang; He Yafeng

    2016-01-01

    Dust molecules are observed in a dusty plasma experiment. By using measurements with high spatial resolution, the formation and dissociation of the dust molecules are studied. The ion cloud in the wake of an upper dust grain attracts the lower dust grain nearby. When the interparticle distance between the upper dust grain and the lower one is less than a critical value, the two dust grains would form a dust molecule. The upper dust grain always leads the lower one as they travel. When the interparticle distance between them is larger than the critical value, the dust molecule would dissociate. (paper)

  20. Trace metals in urban road dust

    International Nuclear Information System (INIS)

    Randazzo, Loredana Antonella; Dongarra, Gaetano; Manno, Emanuela; Varrica, Daniela

    2006-01-01

    Heavy metals associated with urban road dust is a matter for concern as they may have serious effects on biological systems. The bioavailability and potential toxicity of metals bound to urban dust is related to the specific chemical form of the element. In the present article are reported the determinations and chemical speciation of As, Ba, Cr, Cu, Mo, Ni, Pb and Zn in six samples of road dust collected within the urban centre and the outskirts of Palermo [it

  1. Cylindrical dust acoustic waves with transverse perturbation

    International Nuclear Information System (INIS)

    Xue Jukui

    2003-01-01

    The nonlinear dust acoustic waves in dusty plasmas with the combined effects of bounded cylindrical geometry and the transverse perturbation are studied. Using the perturbation method, a cylindrical Kadomtsev-Petviashvili (CKP) equation that describes the dust acoustic waves is deduced for the first time. A particular solution of this CKP equation is also obtained. It is shown that the dust acoustic solitary waves can exist in the CKP equation

  2. The control and prevention of dust explosions

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    Papers presented discussed: explosion characteristics and hybrid mixtures explosion characteristics and influencing factors, propagation of dust explosions in ducts, prevention of dust explosions, desensitization, explosion-proof type of construction, explosion pressure relief, optical flame barriers, slide-valves for explosion protection, Ventex explosion barrier valves, grinding and mixing plants, spray driers, dust explosions in silos, and explosion-proof bucket elevators. One paper has been abstracted separately.

  3. Failure to phytosanitize ash firewood infested with emerald ash borer in a small dry kiln using ISPM-15 standards.

    Science.gov (United States)

    Goebel, P Charles; Bumgardner, Matthew S; Herms, Daniel A; Sabula, Andrew

    2010-06-01

    Although current USDA-APHIS standards suggest that a core temperature of 71.1 degrees C (160 degrees F) for 75 min is needed to adequately sanitize emerald ash borer, Agrilus planipennis Fairmaire-infested firewood, it is unclear whether more moderate (and economical) treatment regimes will adequately eradicate emerald ash borer larvae and prepupae from ash firewood. We constructed a small dry kiln in an effort to emulate the type of technology a small- to medium-sized firewood producer might use to examine whether treatments with lower temperature and time regimes successfully eliminate emerald ash borer from both spilt and roundwood firewood. Using white ash (Fraxinus americana L.) firewood collected from a stand with a heavy infestation of emerald ash borer in Delaware, OH, we treated the firewood using the following temperature and time regime: 46 degrees C (114.8 degrees F) for 30 min, 46 degrees C (114.8 degrees F) for 60 min, 56 degrees C (132.8 degrees F) for 30 min, and 56 degrees C (132.8 degrees F) for 60 min. Temperatures were recorded for the outer 2.54-cm (1-in.) of firewood. After treatment, all firewood was placed under mesh netting and emerald ash borer were allowed to develop and emerge under natural conditions. No treatments seemed to be successful at eliminating emerald ash borer larvae and perpupae as all treatments (including two nontreated controls) experienced some emerald ash borer emergence. However, the 56 degrees C (132.8 degrees F) treatments did result in considerably less emerald ash borer emergence than the 46 degrees C (114.8 degrees F) treatments. Further investigation is needed to determine whether longer exposure to the higher temperature (56 degrees C) will successfully sanitize emerald ash borer-infested firewood.

  4. Ultra high temperature gasification of municipal wastewater primary biosolids in a rotary kiln reactor for the production of synthesis gas.

    Science.gov (United States)

    Gikas, Petros

    2017-12-01

    Primary Fine-Sieved Solids (PFSS) are produced from wastewater by the use of micro-sieves, in place of primary clarification. Biosolids is considered as a nuisance product, however, it contains significant amounts of energy, which can be utilized by biological (anaerobic digestion) or thermal (combustion or gasification) processes. In the present study, an semi-industrial scale UHT rotary kiln gasifier, operating with electric energy, was employed for the gasification of PFSS (at 17% moisture content), collected from a municipal wastewater treatment plant. Two gasification temperatures (950 and 1050 °C) had been tested, with minimal differences, with respect to syngas yield. The system appears to reach steady state after about 30-40 min from start up. The composition of the syngas at near steady state was measured approximately as 62.4% H 2 , 30.0% CO, 2.4% CH 4 and 3.4% CO 2 , plus 1.8% unidentified gases. The potential for electric energy production from the syngas produced is theoretically greater than the electric energy required for gasification. Theoretically, approximately 3.8 MJ/kg PFSS of net electric energy may be produced. However, based on the measured electric energy consumption, and assuming that all the syngas produced is used for electric energy production, addition of excess electric energy (about 0.43 MJ/kg PFSS) is required to break even. The latter is probably due to heat losses to the environment, during the heating process. With the improvement of energy efficiency, the process can be self sustained, form the energy point of view. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Dust control at Yucca Mountain project

    International Nuclear Information System (INIS)

    Kissell, F.; Jurani, R.; Dresel, R.; Reaux, C.

    1999-01-01

    This report describes actions taken to control silica dust at the Yucca Mountain Exploratory Studies Facility, a tunnel located in Southern Nevada that is part of a scientific program to determine site suitability for a potential nuclear waste repository. The rock is a volcanic tuff containing significant percentages of both quartz and cristobalite. Water use for dust control was limited because of scientific test requirements, and this limitation made dust control a difficult task. Results are reported for two drifts, called the Main Loop Drift and the Cross Drift. In the Main Loop Drift, dust surveys and tracer gas tests indicated that air leakage from the TBM head, the primary ventilation duct, and movement of the conveyor belt were all significant sources of dust. Conventional dust control approaches yielded no significant reductions in dust levels. A novel alternative was to install an air cleaning station on a rear deck of the TBM trailing gear. It filtered dust from the contaminated intake air and discharged clean air towards the front of the TBM. The practical effect was to produce dust levels below the exposure limit for all TBM locations except close to the head. In the Cross Drift, better ventilation and an extra set of dust seals on the TBM served to cut down the leakage of dust from the TBM cutter head. However, the conveyor belt was much dustier than the belt in the main loop drift. The problem originated with dirt on the bottom of the belt return side and much spillage from the belt top side. Achieving lower dust levels in hard rock tunneling operations will require new approaches as well as a more meticulous application of existing technology. Planning for dust control will require specific means to deal with dust that leaks from the TBM head, dust that originates with leaky ventilation systems, and dust that comes from conveyor belts. Also, the application of water could be more efficient if automatic controls were used to adjust the water flow

  6. Beryllium dust generation resulting from plasma bombardment

    International Nuclear Information System (INIS)

    Doerner, R.; Mays, C.

    1997-01-01

    The beryllium dust resulting from erosion of beryllium samples subjected to plasma bombardment has been measured in PISCES-B. Loose surface dust was found to be uniformly distributed throughout the device and accounts for 3% of the eroded material. A size distribution measurement of the loose surface dust shows an increasing number of particles with decreasing diameter. Beryllium coatings on surfaces with a line of sight view of the target interaction region account for an additional 33% of the eroded beryllium material. Flaking of these surface layers is observed and is thought to play a significant role in dust generation inside the vacuum vessel. (orig.)

  7. Control of dust production in ITER

    International Nuclear Information System (INIS)

    Rodriguez-Rodrigo, L.; Ciattaglia, S.; Elbez-Uzan, J.

    2006-01-01

    In the last years dust has been observed in a number of fusion devices and is being studied more in detail for understanding in particular the physical phenomena related to its formation, its composition, physical and chemical characteristics, and the amount of produced dust. The extrapolation of dust formation to ITER predicts (with large error bars), a large mass of dust production with a scattered size distribution. To evaluate the impact of dust on safety, assumptions have also been made on radionuclide inventory, and mobility in off-normal events, as well as any postulated contributions the dust may make to effluents or accidental releases. Solid activation products in structures are generally not readily mobilisable in incidental and accidental situations, so that activated dust, tritium and activated corrosions products are the important in-vessel source terms in postulated scenarios that assume a mobilisation and release of some fraction of this inventory. Such a release would require the simultaneous leak or bypass of several robust confinement barriers. Further concerns for dust may be the potential for chemical reactions between dust and coolant in the event of an in-vessel leak, and the theoretical possibility of a dust explosion, either of which could in principle cause a pressure rise that challenges one or more of the confinement barriers. Although these hazards can - and will - be controlled by other measures in the ITER design, application of the principle of Defence in Depth dictates that the dust inventory should also be minimised and controlled to prevent the potential hazard. A well-coordinated R-and-D programme is required to support this dust production control. This document provides from the safety point of view, an overview of existing data given in '' Dossier d'Options de Surete '', the first safety report presented in 2001 to the French Safety Authorities, and ITER documents; it also gathers information on status of studies on activated

  8. The study of ancient porcelain of Hutian kiln site from Five dynasty (902-979) to Ming dynasty (1368-1644) by INAA

    International Nuclear Information System (INIS)

    Lin Cheng; Junling Wang; Rongwu Li; Meitian Li

    2015-01-01

    Minor and trace elements of 398 pieces of ancient porcelain of Hutian kiln site from Five dynasty (AD 902-979) to Ming dynasty (AD 1368-1644) were determined by instrumental neutron activate analysis (INAA). The data of INAA and PCA show the ages of all the porcelain can be divided into Five dynasty, Northern Song dynasty, Southern Song dynasty, Early Yuan dynasty, Later Yuan dynasty and Ming dynasty according to their chemical compositions. Moreover, some archaeological questions about the ancient porcelain are discussion also. (author)

  9. Moessbauer studies of Haltern 70 amphorae from Castro do Vieito, North of Portugal, and of amphora sherds from kilns in the Roman provinces Hispania Baetica and Lusitania

    Energy Technology Data Exchange (ETDEWEB)

    Costa, B. F. O., E-mail: benilde@ci.uc.pt [University of Coimbra, CEMDRX, Physics Department (Portugal); Silva, A. J. M. [Centro de Estudos Arqueologicos das Universidades de Coimbra e do Porto/CAM, Palacio de Sub-Ripas (Portugal); Wagner, F. E.; Wagner, U. [Technical University of Munich, Physics Department (Germany)

    2011-11-15

    Haltern 70 amphora sherds from Castro do Vieito and from kilns in the Roman provinces Baetica and Lusitania were studied by Moessbauer spectroscopy, EDX and XRD. An amphora whose handle was carefully studied must have been fired reducingly at a temperature of or above about 900 Degree-Sign C and cooled in oxidizing conditions in the end. Oxidation and hematite formation went hand in hand, and the amount of hematite formed depended sensitively of the speed of penetration of the oxygen and the cooling rate in the interior of the ceramic body.

  10. Move towards bag filter units in kiln dedusting; Vers l'utilisation de filtres a manches en four a ciment

    Energy Technology Data Exchange (ETDEWEB)

    Schobesberger, M.

    2000-02-01

    Dedusting of kiln gases has become a major concern for cement companies worldwide due to the more and more stringent environmental standards. This short paper draws out an overview of the recent trends in dedusting techniques using bag filters. A comparison is made between different factories and their experience in the use of bag filters made of different materials or used in different operating conditions. The lifetime of these filters is the main problem to deal with and depends on various factors such as the the material used, the air to cloth ratio, the flow rate, temperature, and moisture of the flue gases. (J.S.)

  11. Integrative Analysis of Desert Dust Size and Abundance Suggests Less Dust Climate Cooling

    Science.gov (United States)

    Kok, Jasper F.; Ridley, David A.; Zhou, Qing; Miller, Ron L.; Zhao, Chun; Heald, Colette L.; Ward, Daniel S.; Albani, Samuel; Haustein, Karsten

    2017-01-01

    Desert dust aerosols affect Earths global energy balance through interactions with radiation, clouds, and ecosystems. But the magnitudes of these effects are so uncertain that it remains unclear whether atmospheric dust has a net warming or cooling effect on global climate. Consequently, it is still uncertain whether large changes in atmospheric dust loading over the past century have slowed or accelerated anthropogenic climate change, and the climate impact of possible future alterations in dust loading is similarly disputed. Here we use an integrative analysis of dust aerosol sizes and abundance to constrain the climatic impact of dust through direct interactions with radiation. Using a combination of observational, experimental, and model data, we find that atmospheric dust is substantially coarser than represented in current climate models. Since coarse dust warms global climate, the dust direct radiative effect (DRE) is likely less cooling than the 0.4 W m superscript 2 estimated by models in a current ensemble. We constrain the dust DRE to -0.20 (-0.48 to +0.20) W m superscript 2, which suggests that the dust DRE produces only about half the cooling that current models estimate, and raises the possibility that dust DRE is actually net warming the planet.

  12. Carbohydrate and protein contents of grain dusts in relation to dust morphology.

    Science.gov (United States)

    Dashek, W V; Olenchock, S A; Mayfield, J E; Wirtz, G H; Wolz, D E; Young, C A

    1986-01-01

    Grain dusts contain a variety of materials which are potentially hazardous to the health of workers in the grain industry. Because the characterization of grain dusts is incomplete, we are defining the botanical, chemical, and microbial contents of several grain dusts collected from grain elevators in the Duluth-Superior regions of the U.S. Here, we report certain of the carbohydrate and protein contents of dusts in relation to dust morphology. Examination of the gross morphologies of the dusts revealed that, except for corn, each dust contained either husk or pericarp (seed coat in the case of flax) fragments in addition to respirable particles. When viewed with the light microscope, the fragments appeared as elongated, pointed structures. The possibility that certain of the fragments within corn, settled, and spring wheat were derived from cell walls was suggested by the detection of pentoses following colorimetric assay of neutralized 2 N trifluoroacetic acid hydrolyzates of these dusts. The presence of pentoses together with the occurrence of proteins within water washings of grain dusts suggests that glycoproteins may be present within the dusts. With scanning electron microscopy, each dust was found to consist of a distinct assortment of particles in addition to respirable particles. Small husk fragments and "trichome-like" objects were common to all but corn dust. Images FIGURE 4. FIGURE 5. PMID:3709476

  13. The Electric Environment of Martian Dust Devils

    Science.gov (United States)

    Barth, E. L.; Farrell, W. M.; Rafkin, S. C.

    2017-12-01

    While Martian dust devils have been monitored through decades of observations, we have yet to study their possible electrical effects from in situ instrumentation. However, evidence for the existence of active electrodynamic processes on Mars is provided by laboratory studies of analog material and field campaigns of dust devils on Earth. We have enabled our Mars regional scale atmospheric model (MRAMS) to estimate an upper limit on electric fields generated through dust devil circulations by including charged particles as defined from the Macroscopic Triboelectric Simulation (MTS) code. MRAMS is used to investigate the complex physics of regional, mesoscale, and microscale atmospheric phenomena on Mars; it is a 3-D, nonhydrostatic model, which permits the simulation of atmospheric flows with large vertical accelerations, such as dust devils. MTS is a 3-D particle code which quantifies charging associated with swirling, mixing dust grains; grains of pre-defined sizes and compositions are placed in a simulation box and allowed to move under the influence of winds and gravity. Our MRAMS grid cell size makes our results most applicable to dust devils of a few hundred meters in diameter. We have run a number of simulations to understand the sensitivity of the electric field strength to the particle size and abundance and the amount of charge on each dust grain. We find that Efields can indeed develop in Martian dust convective features via dust grain filtration effects. The overall value of these E-fields is strongly dependent upon dust grain size, dust load, and lifting efficiency, and field strengths can range from 100s of mV/m to 10s of kV/m.

  14. The dust acoustic wave in a bounded dusty plasma with strong electrostatic interactions between dust grains

    International Nuclear Information System (INIS)

    Shukla, Nitin; Shukla, P.K.

    2011-01-01

    The dispersion relation for the dust acoustic wave (DAW) in an unmagnetized dusty plasma cylindrical waveguide is derived, accounting for strong electrostatic interactions between charged dust grains. It is found that the boundary effect limits the radial extent of the DAW. The present result should be helpful for understanding the frequency spectrum of the DAW in a dusty plasma waveguide with strongly coupled charged dust grains. - Highlights: → We study the dust acoustic wave (DAW) in a bounded plasma. → We account for interactions between dust grains. → The boundary effect limits the radial extent of the DAW.

  15. Radioactive dust in the air

    Energy Technology Data Exchange (ETDEWEB)

    Yano, N

    1956-01-01

    An electric precipitator is used to collect dust in the air because its collection efficiency for radioactive substances is up to 10 times that of the impactor of filter-paper types. About 10 cu m of air is filtered during 5 hours, and the trapped dust is measured more than 24 hours after collection to avoid the influence of naturally active substances. The average radioactivity of the air is approximately 10/sup -16/ c/cc. During the period of observation 4 peaks occurred. The dates and maximum levels of artificial activity, respectively, are November 4 to 10, 1954, 1.2 x 10/sup -7/ uc/l; April 11 to 13, 1955, 4.3 x 10/sup -8/ uc/l; November 25 to 28, 1955, maximum unknown; and March 22 to 25, 1956, 1.- x 10/sup -7/ uc/l. The presumed dates and places of detonation corresponding to the peaks are October 31, 1954 northwest of Japan; March 29, 1955, Nevada, US; November 22, 1955, near L. Baikal, USSR; and March 13 to 15, 1956 unknown.

  16. Comet Dust After Deep Impact

    Science.gov (United States)

    Wooden, Diane H.; Harker, David E.; Woodward, Charles E.

    2006-01-01

    When the Deep Impact Mission hit Jupiter Family comet 9P/Tempel 1, an ejecta crater was formed and an pocket of volatile gases and ices from 10-30 m below the surface was exposed (A Hearn et aI. 2005). This resulted in a gas geyser that persisted for a few hours (Sugita et al, 2005). The gas geyser pushed dust grains into the coma (Sugita et a1. 2005), as well as ice grains (Schulz et al. 2006). The smaller of the dust grains were submicron in radii (0-25.3 micron), and were primarily composed of highly refractory minerals including amorphous (non-graphitic) carbon, and silicate minerals including amorphous (disordered) olivine (Fe,Mg)2SiO4 and pyroxene (Fe,Mg)SiO3 and crystalline Mg-rich olivine. The smaller grains moved faster, as expected from the size-dependent velocity law produced by gas-drag on grains. The mineralogy evolved with time: progressively larger grains persisted in the near nuclear region, having been imparted with slower velocities, and the mineralogies of these larger grains appeared simpler and without crystals. The smaller 0.2-0.3 micron grains reached the coma in about 1.5 hours (1 arc sec = 740 km), were more diverse in mineralogy than the larger grains and contained crystals, and appeared to travel through the coma together. No smaller grains appeared at larger coma distances later (with slower velocities), implying that if grain fragmentation occurred, it happened within the gas acceleration zone. These results of the high spatial resolution spectroscopy (GEMINI+Michelle: Harker et 4. 2005, 2006; Subaru+COMICS: Sugita et al. 2005) revealed that the grains released from the interior were different from the nominally active areas of this comet by their: (a) crystalline content, (b) smaller size, (c) more diverse mineralogy. The temporal changes in the spectra, recorded by GEMIM+Michelle every 7 minutes, indicated that the dust mineralogy is inhomogeneous and, unexpectedly, the portion of the size distribution dominated by smaller grains has

  17. The management of house dust mite allergies

    NARCIS (Netherlands)

    Bronswijk, van J.E.M.H.; Schober, G.; Kniest, F.M.

    1990-01-01

    A safe and practical home sanitation procedure for the removal of house dust mites (Dermatophagoides pteronyssinus) and their allergens is described. The severity of mite infestation was assessed with the use of the Acarex test, which measures the concentration of guanine in house dust, and all

  18. A rotating dust cloud in general relativity

    International Nuclear Information System (INIS)

    Bonnor, W.B.

    1977-01-01

    An axially symmetric, stationary exact solution of Einstein's equations for dust is studied. It is asymptotically flat, and represents a rotating dust cloud extending tenuously to infinity, containing a singularity at the centre. An explanation is given as to why there exists no corresponding solution in Newtonian theory. (author)

  19. Dust coagulation in protoplanetary disks : porosity matters

    NARCIS (Netherlands)

    Ormel, C. W.; Spaans, M.; Tielens, A. G. G. M.

    Context. Sticking of colliding dust particles through van der Waals forces is the first stage in the grain growth process in protoplanetary disks, eventually leading to the formation of comets, asteroids and planets. A key aspect of the collisional evolution is the coupling between dust and gas

  20. Correlation between Yellow Dust and Radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    AIZaabia, Mouza A [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of); Kim, Byoung-Jik [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-10-15

    In East Asia, yellow dust or Asian Dust (AD) outbreaks are among the largest contributors of wind-blown dust that carry natural and anthropogenic radionuclides and subsequently alter their concentration and distribution throughout the environment. Although the Korean Peninsula has been experiencing AD events since ancient times, the research has tended to focus on the transport routes and characteristics of AD, rather than on its impact on radionuclide activity levels. This paper examines the relationship between radionuclide concentration in the air and the frequency of dusty days in South Korea during AD intrusion events. It also investigates whether increased radionuclide concentration is a function of either more mass or more dust contamination. In this study, significant linear correlations of gamma-emitting radionuclides were found with mass of dust and occurrence frequency of AD. Regardless of the source origin of the dust, {sup 137}Cs and {sup 7}Be concentration primarily depended on dust mass in the filter. Nonetheless, the correlations were greatly distorted in 2011 and in the spring season, particularly the correlations with AD days that were far below that of the correlations obtained for the whole study period. A possible explanation of these conflicting results is that a change in the dust source could appreciably alter the concentration, deposition, and distribution of airborne radionuclides.

  1. Correlation between Yellow Dust and Radioactivity

    International Nuclear Information System (INIS)

    AIZaabia, Mouza A; Kim, Byoung-Jik

    2015-01-01

    In East Asia, yellow dust or Asian Dust (AD) outbreaks are among the largest contributors of wind-blown dust that carry natural and anthropogenic radionuclides and subsequently alter their concentration and distribution throughout the environment. Although the Korean Peninsula has been experiencing AD events since ancient times, the research has tended to focus on the transport routes and characteristics of AD, rather than on its impact on radionuclide activity levels. This paper examines the relationship between radionuclide concentration in the air and the frequency of dusty days in South Korea during AD intrusion events. It also investigates whether increased radionuclide concentration is a function of either more mass or more dust contamination. In this study, significant linear correlations of gamma-emitting radionuclides were found with mass of dust and occurrence frequency of AD. Regardless of the source origin of the dust, 137 Cs and 7 Be concentration primarily depended on dust mass in the filter. Nonetheless, the correlations were greatly distorted in 2011 and in the spring season, particularly the correlations with AD days that were far below that of the correlations obtained for the whole study period. A possible explanation of these conflicting results is that a change in the dust source could appreciably alter the concentration, deposition, and distribution of airborne radionuclides

  2. Measurement of nicotine in household dust

    International Nuclear Information System (INIS)

    Kim, Sungroul; Aung, Ther; Berkeley, Emily; Diette, Gregory B.; Breysse, Patrick N.

    2008-01-01

    An analytical method of measuring nicotine in house dust was optimized and associations among three secondhand smoking exposure markers were evaluated, i.e., nicotine concentrations of both house dust and indoor air, and the self-reported number of cigarettes smoked daily in a household. We obtained seven house dust samples from self-reported nonsmoking homes and 30 samples from smoking homes along with the information on indoor air nicotine concentrations and the number of cigarettes smoked daily from an asthma cohort study conducted by the Johns Hopkins Center for Childhood Asthma in the Urban Environment. House dust nicotine was analyzed by isotope dilution gas chromatography-mass spectrometry (GC/MS). Using our optimized method, the median concentration of nicotine in the dust of self-reported nonsmoking homes was 11.7 ng/mg while that of smoking homes was 43.4 ng/mg. We found a substantially positive association (r=0.67, P<0.0001) between house dust nicotine concentrations and the numbers of cigarettes smoked daily. Optimized analytical methods showed a feasibility to detect nicotine in house dust. Our results indicated that the measurement of nicotine in house dust can be used potentially as a marker of longer term SHS exposure

  3. 30 CFR 56.9315 - Dust control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Dust control. 56.9315 Section 56.9315 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... control. Dust shall be controlled at muck piles, material transfer points, crushers, and on haulage roads...

  4. Role of dust in H II regions

    International Nuclear Information System (INIS)

    Sarazin, C.L.

    1975-01-01

    The purpose of this dissertation is to determine quantitatively the effects of U.V. absorbing dust on H II regions, and compare these effects with observations. Many observations indicate that dust grains are present within H II regions. An analytic theory is presented which describes all three of the effects of dust in H II regions. Although this model is relatively crude, it is useful in determining the approximate size of the modifications due to dust. In order to explore this problem more carefully, detailed numerical models of H II regions with dust were constructed. The ionization and thermal structure of these model H II regions is discussed. The observational consequences of the presence of dust are explored; the optical line intensities, radio continuum and line fluxes, and infrared emission of model H II regions with dust are given. These numerical models are compared with observations of diffuse nebulae. The optical line ratios are compared to several nearby bright H II regions, and it is found that the dust models may explain several anomalies in their spectrum

  5. The Continuous Monitoring of Desert Dust using an Infrared-based Dust Detection and Retrieval Method

    Science.gov (United States)

    Duda, David P.; Minnis, Patrick; Trepte, Qing; Sun-Mack, Sunny

    2006-01-01

    Airborne dust and sand are significant aerosol sources that can impact the atmospheric and surface radiation budgets. Because airborne dust affects visibility and air quality, it is desirable to monitor the location and concentrations of this aerosol for transportation and public health. Although aerosol retrievals have been derived for many years using visible and near-infrared reflectance measurements from satellites, the detection and quantification of dust from these channels is problematic over bright surfaces, or when dust concentrations are large. In addition, aerosol retrievals from polar orbiting satellites lack the ability to monitor the progression and sources of dust storms. As a complement to current aerosol dust retrieval algorithms, multi-spectral thermal infrared (8-12 micron) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) and the Meteosat-8 Spinning Enhanced Visible and Infrared Imager (SEVIRI) are used in the development of a prototype dust detection method and dust property retrieval that can monitor the progress of Saharan dust fields continuously, both night and day. The dust detection method is incorporated into the processing of CERES (Clouds and the Earth s Radiant Energy System) aerosol retrievals to produce dust property retrievals. Both MODIS (from Terra and Aqua) and SEVERI data are used to develop the method.

  6. Dust plume formation in the free troposphere and aerosol size distribution during the Saharan Mineral Dust Experiment in North Africa

    KAUST Repository

    Khan, Basit Ali; Stenchikov, Georgiy L.; Weinzierl, Bernadett; Kalenderski, Stoitchko; Osipov, Sergey

    2015-01-01

    , this study combines model simulations and dust observations collected during the first stage of the Saharan Mineral Dust Experiment (SAMUM-I), which sampled dust events that extended from Morocco to Portugal, and investigated the spatial distribution

  7. Extracting lunar dust parameters from image charge signals produced by the Lunar Dust Experiment

    Science.gov (United States)

    Stanley, J.; Kempf, S.; Horanyi, M.; Szalay, J.

    2015-12-01

    The Lunar Dust Experiment (LDEX) onboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) is an impact ionization dust detector used to characterize the lunar dust exosphere generated by the impacts of large interplanetary particles and meteor streams (Horanyi et al., 2015). In addition to the mass and speed of these lofted particles, LDEX is sensitive to their charge. The resulting signatures of impact events therefore provide valuable information about not only the ambient plasma environment, but also the speed vectors of these dust grains. Here, impact events produced from LDEX's calibration at the Dust Accelerator Laboratory are analyzed using an image charge model derived from the electrostatic simulation program, Coulomb. We show that parameters such as dust grain speed, size, charge, and position of entry into LDEX can be recovered and applied to data collected during LADEE's seven-month mission.

  8. Nepal Ambient Monitoring and Source Testing Experiment (NAMaSTE): Emissions of particulate matter from wood and dung cooking fires, brick kilns, generators, trash and crop residue burning

    Science.gov (United States)

    Stone, Elizabeth; Jayarathne, Thilina; Stockwell, Chelsea; Christian, Ted; Bhave, Prakash; Siva Praveen, Puppala; Panday, Arnico; Adhikari, Sagar; Maharjan, Rashmi; Goetz, Doug; DeCarlo, Peter; Saikawa, Eri; Yokelson, Robert

    2016-04-01

    The Nepal Ambient Monitoring and Source Testing Experiment (NAMASTE) field campaign targeted the in situ characterization of widespread and under-sampled combustion sources. In Kathmandu and the Terai, southern Nepal's flat plains, samples of fine particulate matter (PM2.5) were collected from wood and dung cooking fires (n = 22), generators (n = 2), groundwater pumps (n = 2), clamp kilns (n = 3), zig-zag kilns (n = 3), trash burning (n = 4), one heating fire, and one crop residue fire. Co-located measurements of carbon dioxide, carbon monoxide, and volatile organic compounds allowed for the application of the carbon mass balance approach to estimate emission factors for PM2.5, elemental carbon, organic carbon, and water-soluble inorganic ions. Organic matter was chemically speciated using gas chromatography - mass spectrometry for polycyclic aromatic hydrocarbons, sterols, n-alkanes, hopanes, steranes, and levoglucosan, which accounted for 2-8% of the measured organic carbon. These data were used to develop molecular-marker based profiles for use in source apportionment modeling. This study provides quantitative emission factors for particulate matter and its constituents for many important combustion sources in Nepal and South Asia.

  9. The emission of particulate matters and heavy metals from cement kilns – case study: co-incineration of tires in Serbia

    Directory of Open Access Journals (Sweden)

    Dušan Todorović

    2010-09-01

    Full Text Available Co-incineration of wastes started more than 20 years ago. In the last 10 years, the use of alternative fuels in the cement industry is continuously increasing. The use of solid wastes in cement kilns is one of the best technologies for a complete and safe destruction of these wastes, due to the fact that there is a simultaneous benefit of destroying wastes and getting the energy. However, particulate matters (PM and gaseous chemicals emitted from a source into the environment could be directly transmitted to humans through air inhalation. Therefore, for accurate health risk estimation, the emission of pollutants must be determined. In this work, the analysis of the emission of different pollutants when replacing partially the fuel type used in a cement kiln is done. PM, PM10, heavy metals and inorganic pollutants are analyzed. The methods used for sampling and analysis are the standard methods suggested by the EU regulations for stack analysis. Experimental results have shown the encouraging results: in particular clinker characteristics were unmodified, and stack emissions (NOx, SO2 and CO mainly were in the case of tires, slightly incremented but remaining almost always below the law imposed limits, and in some cases were even decreased.

  10. Heating of Porous Icy Dust Aggregates

    Energy Technology Data Exchange (ETDEWEB)

    Sirono, Sin-iti [Earth and Environmental Sciences, Nagoya University, Tikusa-ku, Furo-cho, Nagoya 464-8601 (Japan)

    2017-06-10

    At the beginning of planetary formation, highly porous dust aggregates are formed through coagulation of dust grains. Outside the snowline, the main component of an aggregate is H{sub 2}O ice. Because H{sub 2}O ice is formed in amorphous form, its thermal conductivity is extremely small. Therefore, the thermal conductivity of an icy dust aggregate is low. There is a possibility of heating inside an aggregate owing to the decay of radionuclides. It is shown that the temperature increases substantially inside an aggregate, leading to crystallization of amorphous ice. During the crystallization, the temperature further increases sufficiently to continue sintering. The mechanical properties of icy dust aggregates change, and the collisional evolution of dust aggregates is affected by the sintering.

  11. The relaxation of plasmas with dust particles

    International Nuclear Information System (INIS)

    Chutov, Yu.I.; Kravchenko, A.Yu.; Schram, P.P.J.M.

    1997-01-01

    Various parameters of relaxing plasmas with dust particles including the electron and ion energy distributions function are numerically simulated at various parameters of the dust particles using the PIC method and taking into account the dynamics of the dust particle charge without the assumption about the equilibrium of electrons and ions. Coulomb collisions are taken into account in the framework of the method of stochastic differential equations. The relaxation of bounded plasma clouds expanding into a vacuum as well as the relaxation of a uniform plasma, in which dust particles appear at some initial time, are investigated. The obtained results show that the relaxation of plasmas can be accompanied by a deviation of the ion distribution function from equilibrium as well as a change of the mean energy of electrons and ions because of the dependence of the collection of electrons and ions by dust particles on their energy. (author)

  12. Recycling of steelmaking dusts: The Radust concept

    Directory of Open Access Journals (Sweden)

    Jalkanen H.

    2005-01-01

    Full Text Available Recycling of dusts and other wastes of steelmaking is becoming to a necessity of two reasons: due to high contents of iron oxides dusts are valuable raw material for steelmaking and tightening environmental legislation makes the landfill disposal of wastes more expensive. Fine dust fractions from various stages of steelmaking route contain besides iron and carbon heavy metals especially zinc and lead and heavy hydrocarbons that are acceptable neither for landfill disposal nor for recycling back to processes without any spe4cial treatments. Some theoretical and practical aspects concerning high temperature treatments of steelmaking dusts for removal of hazardous components and production of clean high iron raw material for recycling is discussed in this paper. The Radust technology developed at Koverhar steelwork in Finland for treatment of the most problematic fine fractions of blast furnace and oxygen converter dusts is shortly presented and discussed.

  13. Dust storm events over Delhi: verification of dust AOD forecasts with satellite and surface observations

    Science.gov (United States)

    Singh, Aditi; Iyengar, Gopal R.; George, John P.

    2016-05-01

    Thar desert located in northwest part of India is considered as one of the major dust source. Dust storms originate in Thar desert during pre-monsoon season, affects large part of Indo-Gangetic plains. High dust loading causes the deterioration of the ambient air quality and degradation in visibility. Present study focuses on the identification of dust events and verification of the forecast of dust events over Delhi and western part of IG Plains, during the pre-monsoon season of 2015. Three dust events have been identified over Delhi during the study period. For all the selected days, Terra-MODIS AOD at 550 nm are found close to 1.0, while AURA-OMI AI shows high values. Dust AOD forecasts from NCMRWF Unified Model (NCUM) for the three selected dust events are verified against satellite (MODIS) and ground based observations (AERONET). Comparison of observed AODs at 550 nm from MODIS with NCUM predicted AODs reveals that NCUM is able to predict the spatial and temporal distribution of dust AOD, in these cases. Good correlation (~0.67) is obtained between the NCUM predicted dust AODs and location specific observations available from AERONET. Model under-predicted the AODs as compared to the AERONET observations. This may be mainly because the model account for only dust and no anthropogenic activities are considered. The results of the present study emphasize the requirement of more realistic representation of local dust emission in the model both of natural and anthropogenic origin, to improve the forecast of dust from NCUM during the dust events.

  14. Dust Evolution in Galaxy Cluster Simulations

    Science.gov (United States)

    Gjergo, Eda; Granato, Gian Luigi; Murante, Giuseppe; Ragone-Figueroa, Cinthia; Tornatore, Luca; Borgani, Stefano

    2018-06-01

    We implement a state-of-the-art treatment of the processes affecting the production and Interstellar Medium (ISM) evolution of carbonaceous and silicate dust grains within SPH simulations. We trace the dust grain size distribution by means of a two-size approximation. We test our method on zoom-in simulations of four massive (M200 ≥ 3 × 1014M⊙) galaxy clusters. We predict that during the early stages of assembly of the cluster at z ≳ 3, where the star formation activity is at its maximum in our simulations, the proto-cluster regions are rich in dusty gas. Compared to the case in which only dust production in stellar ejecta is active, if we include processes occurring in the cold ISM,the dust content is enhanced by a factor 2 - 3. However, the dust properties in this stage turn out to be significantly different from those observationally derived for the average Milky Way dust, and commonly adopted in calculations of dust reprocessing. We show that these differences may have a strong impact on the predicted spectral energy distributions. At low redshift in star forming regions our model reproduces reasonably well the trend of dust abundances over metallicity as observed in local galaxies. However we under-produce by a factor of 2 to 3 the total dust content of clusters estimated observationally at low redshift, z ≲ 0.5 using IRAS, Planck and Herschel satellites data. This discrepancy does not subsist by assuming a lower sputtering efficiency, which erodes dust grains in the hot Intracluster Medium (ICM).

  15. Dust in the Quasar Wind (Artist Concept)

    Science.gov (United States)

    2007-01-01

    Dusty grains -- including tiny specks of the minerals found in the gemstones peridot, sapphires and rubies -- can be seen blowing in the winds of a quasar, or active black hole, in this artist's concept. The quasar is at the center of a distant galaxy. Astronomers using NASA's Spitzer Space Telescope found evidence that such quasar winds might have forged these dusty particles in the very early universe. The findings are another clue in an ongoing cosmic mystery: where did all the dust in our young universe come from? Dust is crucial for efficient star formation as it allows the giant clouds where stars are born to cool quickly and collapse into new stars. Once a star has formed, dust is also needed to make planets and living creatures. Dust has been seen as far back as when the universe was less than a tenth of its current age, but how did it get there? Most dust in our current epoch forms in the winds of evolved stars that did not exist when the universe was young. Theorists had predicted that winds from quasars growing in the centers of distant galaxies might be a source of this dust. While the environment close to a quasar is too hot for large molecules like dust grains to survive, dust has been found in the cooler, outer regions. Astronomers now have evidence that dust is created in these outer winds. Using Spitzer's infrared spectrograph instrument, scientists found a wealth of dust grains in a quasar called PG2112+059 located at the center of a galaxy 8 billion light-years away. The grains - including corundum (sapphires and rubies); forsterite (peridot); and periclase (naturally occurring in marble) - are not typically found in galaxies without quasars, suggesting they might have been freshly formed in the quasar's winds.

  16. High Latitude Dust in the Earth System

    Science.gov (United States)

    Bullard, Joanna E.; Baddock, Matthew; Bradwell, Tom; Crusius, John; Darlington, Eleanor; Gaiero, Diego; Gasso, Santiago; Gisladottir, Gudrun; Hodgkins, Richard; McCulloch, Robert; hide

    2016-01-01

    Natural dust is often associated with hot, subtropical deserts, but significant dust events have been reported from cold, high latitudes. This review synthesizes current understanding of high-latitude (> or = 50degN and > or = 40degS) dust source geography and dynamics and provides a prospectus for future research on the topic. Although the fundamental processes controlling aeolian dust emissions in high latitudes are essentially the same as in temperate regions, there are additional processes specific to or enhanced in cold regions. These include low temperatures, humidity, strong winds, permafrost and niveo-aeolian processes all of which can affect the efficiency of dust emission and distribution of sediments. Dust deposition at high latitudes can provide nutrients to the marine system, specifically by contributing iron to high-nutrient, low-chlorophyll oceans; it also affects ice albedo and melt rates. There have been no attempts to quantify systematically the expanse, characteristics, or dynamics of high-latitude dust sources. To address this, we identify and compare the main sources and drivers of dust emissions in the Northern (Alaska, Canada, Greenland, and Iceland) and Southern (Antarctica, New Zealand, and Patagonia) Hemispheres. The scarcity of year-round observations and limitations of satellite remote sensing data at high latitudes are discussed. It is estimated that under contemporary conditions high-latitude sources cover >500,000 sq km and contribute at least 80-100 Tg/yr1 of dust to the Earth system (approx. 5% of the global dust budget); both are projected to increase under future climate change scenarios.

  17. Spatial analysis of charcoal kiln remains in the former royal forest district Tauer (Lower Lusatia, North German Lowlands)

    Science.gov (United States)

    Raab, Alexandra; Schneider, Anna; Bonhage, Alexander; Takla, Melanie; Hirsch, Florian; Müller, Frank; Rösler, Horst; Heußner, Karl-Uwe

    2016-04-01

    Archaeological excavations have revealed more than thousand charcoal kiln remains (CKRs) in the prefield of the active opencast lignite mine Jänschwalde, situated about 150 km SE of Berlin (SE Brandenburg, Germany). The charcoal was mainly produced for the ironwork Peitz nearby, which operated from the 16th to the mid-19th centuries. In a first approach, to estimate the dimension of the charcoal production, CKRs were mapped on shaded-relief maps (SRMs) derived from high-resolution LiDAR data (Raab et al. 2015). Subsequently, for a selected test area, identified CKRs on the SRMs were compared with archaeologically excavated CKRs in the field. This survey showed a considerably number of falsely detected sites. Therefore, the data was critically re-evaluated using additional relief visualisations. Further, we extended the CKR mapping to areas which are not archaeologically investigated. The study area, the former royal forest district Tauer, consists of two separate areas: the Tauersche Heide (c. 96 km2 area) N of Peitz and the area Jänschwalde (c. 32 km2 area) NE of Peitz. The study area is characterized by a flat topography. Different former and current anthropogenic uses (e.g., military training, solar power plant, forestry measures) have affected the study area, resulting in extensive disturbances of the terrain surface. The revised CKR abundance in the study area Jänschwalde was considerably smaller than the numbers produced by our first approach. Further, the CKR mapping revealed, that a total record of the CKRs is not possible for various reasons. Despite these limitations, a solid database can be provided for a much larger area than before. Basic statistic parameters of the CKR diameters and all comparative statistical tests were calculated using SPSS. To detect underlying spatial relationships in the CKR site distribution, we applied the Getis-Ord Gi* statistic, a method to test for local spatial autocorrelation between neighbouring sites. The test is

  18. Asian dust events of April 1998

    Science.gov (United States)

    Husar, R.B.; Tratt, D.M.; Schichtel, B.A.; Falke, S.R.; Li, F.; Jaffe, D.; Gasso, S.; Gill, T.; Laulainen, N.S.; Lu, F.; Reheis, M.C.; Chun, Y.; Westphal, D.; Holben, B.N.; Gueymard, C.; McKendry, I.; Kuring, N.; Feldman, G.C.; McClain, C.; Frouin, R.J.; Merrill, J.; DuBois, D.; Vignola, F.; Murayama, T.; Nickovic, S.; Wilson, W.E.; Sassen, K.; Sugimoto, N.; Malm, W.C.

    2001-01-01

    On April 15 and 19, 1998, two intense dust storms were generated over the Gobi desert by springtime low-pressure systems descending from the northwest. The windblown dust was detected and its evolution followed by its yellow color on SeaWiFS satellite images, routine surface-based monitoring, and through serendipitous observations. The April 15 dust cloud was recirculating, and it was removed by a precipitating weather system over east Asia. The April 19 dust cloud crossed the Pacific Ocean in 5 days, subsided to the surface along the mountain ranges between British Columbia and California, and impacted severely the optical and the concentration environments of the region. In east Asia the dust clouds increased the albedo over the cloudless ocean and land by up to 10-20%, but it reduced the near-UV cloud reflectance, causing a yellow coloration of all surfaces. The yellow colored backscattering by the dust eludes a plausible explanation using simple Mie theory with constant refractive index. Over the West Coast the dust layer has increased the spectrally uniform optical depth to about 0.4, reduced the direct solar radiation by 30-40%, doubled the diffuse radiation, and caused a whitish discoloration of the blue sky. On April 29 the average excess surface-level dust aerosol concentration over the valleys of the West Coast was about 20-50 ??g/m3 with local peaks >100 ??g/m3. The dust mass mean diameter was 2-3 ??m, and the dust chemical fingerprints were evident throughout the West Coast and extended to Minnesota. The April 1998 dust event has impacted the surface aerosol concentration 2-4 times more than any other dust event since 1988. The dust events were observed and interpreted by an ad hoc international web-based virtual community. It would be useful to set up a community-supported web-based infrastructure to monitor the global aerosol pattern for such extreme aerosol events, to alert and to inform the interested communities, and to facilitate collaborative

  19. Austrian emission inventory for dust

    International Nuclear Information System (INIS)

    Winiwarter, W.; Trenker, C.; Hoeflinger, W.

    2001-09-01

    For the first time, Austrian emissions of anthropogenic particulate matter emissions to the atmosphere have been estimated. Results have been reported as total suspended particles (TSP) as well as for the fractions of particles smaller than 10 μm or 2.5 μm aerodynamic diameter (PM 10 , PM 2.5 ), respectively. Base years for the inventory were 1990, 1995 and 1999. Excluded from this assessment is wind blown dust, which has been considered a natural source here. National statistics have been applied, specifically those also used previously in the Austrian air pollution inventory (OLI). Emission factors have been taken from literature compilations, only for exceptional cases specific Austrian assessments were performed or original literature on emission measurements was consulted. Resuspension of dust by road traffic emerged as the most important source. For the size fraction of PM 10 this source contributed about half of the emissions, when applying the calculation scheme by the U.S. EPA. While this scheme is widely used and well documented, its validity is currently subject of intense scientific debate. As these results do not seem to coincide with ambient air measurements, resuspension of road dust is considered separately and not now included in the national total. The sum of all other sources increases from 75,000 t of TSP in 1990 and 1995 to 77,000 t in 1999, while both PM 10 and PM 2.5 exhibit decreasing tendency (at 45,000 t and 26,000 t in 1999, respectively). The increase in TSP derives from increasing traffic and friction related emissions (tire wear, break wear), decrease of the finer particulate matter is due to reductions in firewood consumption for domestic heating. Most important source sectors are fugitive emissions from material transfer in industry as well as the building industry and the tilling of agricultural land. Common to these sources is the high uncertainty of available data. Wood combustion is the most important of the non

  20. The Spatial Variation of Dust Particulate Matter Concentrations during Two Icelandic Dust Storms in 2015

    Directory of Open Access Journals (Sweden)

    Pavla Dagsson-Waldhauserova

    2016-06-01

    Full Text Available Particulate matter mass concentrations and size fractions of PM1, PM2.5, PM4, PM10, and PM15 measured in transversal horizontal profile of two dust storms in southwestern Iceland are presented. Images from a camera network were used to estimate the visibility and spatial extent of measured dust events. Numerical simulations were used to calculate the total dust flux from the sources as 180,000 and 280,000 tons for each storm. The mean PM15 concentrations inside of the dust plumes varied from 10 to 1600 µg·m−3 (PM10 = 7 to 583 µg·m−3. The mean PM1 concentrations were 97–241 µg·m−3 with a maximum of 261 µg·m−3 for the first storm. The PM1/PM2.5 ratios of >0.9 and PM1/PM10 ratios of 0.34–0.63 show that suspension of volcanic materials in Iceland causes air pollution with extremely high PM1 concentrations, similar to polluted urban areas in Europe or Asia. Icelandic volcanic dust consists of a higher proportion of submicron particles compared to crustal dust. Both dust storms occurred in relatively densely inhabited areas of Iceland. First results on size partitioning of Icelandic dust presented here should challenge health authorities to enhance research in relation to dust and shows the need for public dust warning systems.

  1. Emissions of metals and polychlorinated dibenzo(p)dioxins and furans (PCDD/Fs) from Portland cement manufacturing plants: inter-kiln variability and dependence on fuel-types.

    Science.gov (United States)

    Zemba, Stephen; Ames, Michael; Green, Laura; Botelho, Maria João; Gossman, David; Linkov, Igor; Palma-Oliveira, José

    2011-09-15

    Emissions from Portland cement manufacturing facilities may increase health risks in nearby populations and are thus subject to stringent regulations. Direct testing of pollutant concentrations in exhaust gases provides the best basis for assessing the extent of these risks. However, these tests (i) are often conducted under stressed, rather than typical, operating conditions, (ii) may be limited in number and duration, and (iii) may be influenced by specific fuel-types and attributes of individual kilns. We report here on the results of more than 150 emissions-tests conducted of two kilns at a Portland cement manufacturing plant in Portugal. The tests measured various regulated metals and polychlorinated dibenzo(p)dioxins and furans (PCDD/Fs). Stack-gas concentrations of pollutants were found to be highly variable, with standard deviations on the order of mean values. Emission rates of many pollutants were higher when coal was used as the main kiln fuel (instead of petroleum coke). Use of various supplemental fuels, however, had little effect on stack emissions, and few statistically significant differences were observed when hazardous waste was included in the fuel mix. Significant differences in emissions for some pollutants were observed between the two kilns despite their similar designs and uses of similar fuels. All measured values were found to be within applicable regulatory limits. Published by Elsevier B.V.

  2. Kuiper Belt Dust Grains as a Source of Interplanetary Dust Particles

    Science.gov (United States)

    Liou, Jer-Chyi; Zook, Herbert A.; Dermott, Stanley F.

    1996-01-01

    The recent discovery of the so-called Kuiper belt objects has prompted the idea that these objects produce dust grains that may contribute significantly to the interplanetary dust population. In this paper, the orbital evolution of dust grains, of diameters 1 to 9 microns, that originate in the region of the Kuiper belt is studied by means of direct numerical integration. Gravitational forces of the Sun and planets, solar radiation pressure, as well as Poynting-Robertson drag and solar wind drag are included. The interactions between charged dust grains and solar magnetic field are not considered in the model. Because of the effects of drag forces, small dust grains will spiral toward the Sun once they are released from their large parent bodies. This motion leads dust grains to pass by planets as well as encounter numerous mean motion resonances associated with planets. Our results show that about 80% of the Kuiper belt grains are ejected from the Solar System by the giant planets, while the remaining 20% of the grains evolve all the way to the Sun. Surprisingly, the latter dust grains have small orbital eccentricities and inclinations when they cross the orbit of the Earth. This makes them behave more like asteroidal than cometary-type dust particles. This also enhances their chances of being captured by the Earth and makes them a possible source of the collected interplanetary dust particles; in particular, they represent a possible source that brings primitive/organic materials from the outer Solar System to the Earth. When collisions with interstellar dust grains are considered, however, Kuiper belt dust grains around 9 microns appear likely to be collisionally shattered before they can evolve toward the inner part of the Solar System. The collision destruction can be applied to Kuiper belt grains up to about 50 microns. Therefore, Kuiper belt dust grains within this range may not be a significant part of the interplanetary dust complex in the inner Solar

  3. Dust grains from the heart of supernovae

    Science.gov (United States)

    Bocchio, M.; Marassi, S.; Schneider, R.; Bianchi, S.; Limongi, M.; Chieffi, A.

    2016-03-01

    Dust grains are classically thought to form in the winds of asymptotic giant branch (AGB) stars. However, there is increasing evidence today for dust formation in supernovae (SNe). To establish the relative importance of these two classes of stellar sources of dust, it is important to know the fraction of freshly formed dust in SN ejecta that is able to survive the passage of the reverse shock and be injected in the interstellar medium. With this aim, we have developed a new code, GRASH_Rev, that allows following the dynamics of dust grains in the shocked SN ejecta and computing the time evolution of the mass, composition, and size distribution of the grains. We considered four well-studied SNe in the Milky Way and Large Magellanic Cloud: SN 1987A, CasA, the Crab nebula, and N49. These sources have been observed with both Spitzer and Herschel, and the multiwavelength data allow a better assessment the mass of warm and cold dust associated with the ejecta. For each SN, we first identified the best explosion model, using the mass and metallicity of the progenitor star, the mass of 56Ni, the explosion energy, and the circumstellar medium density inferred from the data. We then ran a recently developed dust formation model to compute the properties of freshly formed dust. Starting from these input models, GRASH_Rev self-consistently follows the dynamics of the grains, considering the effects of the forward and reverse shock, and allows predicting the time evolution of the dust mass, composition, and size distribution in the shocked and unshocked regions of the ejecta. All the simulated models aagree well with observations. Our study suggests that SN 1987A is too young for the reverse shock to have affected the dust mass. Hence the observed dust mass of 0.7-0.9 M⊙ in this source can be safely considered as indicative of the mass of freshly formed dust in SN ejecta. Conversely, in the other three SNe, the reverse shock has already destroyed between 10-40% of the

  4. Dust limit management strategy in tokamaks

    International Nuclear Information System (INIS)

    Rosanvallon, S.; Grisolia, C.; Andrew, P.; Ciattaglia, S.; Delaporte, P.; Douai, D.; Garnier, D.; Gauthier, E.; Gulden, W.; Hong, S.H.; Pitcher, S.; Rodriguez, L.; Taylor, N.; Tesini, A.; Vartanian, S.; Vatry, A.; Wykes, M.

    2009-01-01

    Dust is produced in tokamaks by the interaction between the plasma and the plasma facing components. Dust has not yet been of a major concern in existing tokamaks mainly because the quantity is small and these devices are not nuclear facilities. However, in ITER and in future reactors, it will represent operational and potential safety issues. From a safety point of view, in order to control the potential dust hazard, the current ITER strategy is based on a defense in depth approach designed to provide reliable confinement systems, to avoid failures, and to measure and minimise the dust inventory. In addition, R and D is put in place for optimisation of the proposed methods, such as improvement of measurement, dust cleaning and the reduction of dust production. The aim of this paper is to present the approach for the control of the dust inventory, relying on the monitoring of envelope values and the development of removal techniques already developed in the existing tokamaks or plasma dedicated devices or which will need further research and development in order to be integrated in ITER.

  5. Dust limit management strategy in tokamaks

    Science.gov (United States)

    Rosanvallon, S.; Grisolia, C.; Andrew, P.; Ciattaglia, S.; Delaporte, P.; Douai, D.; Garnier, D.; Gauthier, E.; Gulden, W.; Hong, S. H.; Pitcher, S.; Rodriguez, L.; Taylor, N.; Tesini, A.; Vartanian, S.; Vatry, A.; Wykes, M.

    2009-06-01

    Dust is produced in tokamaks by the interaction between the plasma and the plasma facing components. Dust has not yet been of a major concern in existing tokamaks mainly because the quantity is small and these devices are not nuclear facilities. However, in ITER and in future reactors, it will represent operational and potential safety issues. From a safety point of view, in order to control the potential dust hazard, the current ITER strategy is based on a defense in depth approach designed to provide reliable confinement systems, to avoid failures, and to measure and minimise the dust inventory. In addition, R&D is put in place for optimisation of the proposed methods, such as improvement of measurement, dust cleaning and the reduction of dust production. The aim of this paper is to present the approach for the control of the dust inventory, relying on the monitoring of envelope values and the development of removal techniques already developed in the existing tokamaks or plasma dedicated devices or which will need further research and development in order to be integrated in ITER.

  6. Hypervelocity Dust Injection for Plasma Diagnostic Applications

    Science.gov (United States)

    Ticos, Catalin

    2005-10-01

    Hypervelocity micron-size dust grain injection was proposed for high-temperature magnetized plasma diagnosis. Multiple dust grains are launched simultaneously into high temperature plasmas at several km/s or more. The hypervelocity dust grains are ablated by the electron and ion fluxes. Fast imaging of the resulting luminous plumes attached to each grain is expected to yield local magnetic field vectors. Combination of multiple local magnetic field vectors reproduces 2D or even 3D maps of the internal magnetic field topology. Key features of HDI are: (1) a high spatial resolution, due to a relatively small transverse size of the elongated tail, and (2) a small perturbation level, as the dust grains introduce negligible number of particles compared to the plasma particle inventory. The latter advantage, however, could be seriously compromised if the gas load from the accelerator has an unobstructed access to the diagnosed plasma. Construction of a HDI diagnostic for National Spherical Torus Experiment (NSTX), which includes a coaxial plasma gun for dust grain acceleration, is underway. Hydrogen and deuterium gas discharges inside accelerator are created by a ˜ 1 mF capacitor bank pre-charged up to 10 kV. The diagnostic apparatus also comprises a dust dispenser for pre-loading the accelerator with dust grains, and an imaging system that has a high spatial and temporal resolution.

  7. Testing of a Plasmadynamic Hypervelocity Dust Accelerator

    Science.gov (United States)

    Ticos, Catalin M.; Wang, Zhehui; Dorf, Leonid A.; Wurden, G. A.

    2006-10-01

    A plasmadynamic accelerator for microparticles (or dust grains) has been designed, built and tested at Los Alamos National laboratory. The dust grains are expected to be accelerated to hypervelocities on the order of 1-30 km/s, depending on their size. The key components of the plasmadynamic accelerator are a coaxial plasma gun operated at 10 kV, a dust dispenser activated by a piezoelectric transducer, and power and remote-control systems. The coaxial plasma gun produces a high density (10^18 cm-3) and low temperature (˜ 1 eV) plasma in deuterium ejected by J x B forces, which provides drag on the dust particles in its path. Carbon dust particles will be used, with diameters from 1 to 50 μm. The plasma parameters produced in the coaxial gun are presented and their implication to dust acceleration is discussed. High speed dust will be injected in the National Spherical Torus Experiment to measure the pitch angle of magnetic field lines.

  8. Featured Image: Making Dust in the Lab

    Science.gov (United States)

    Kohler, Susanna

    2017-12-01

    This remarkable photograph (which spans only 10 m across; click for a full view) reveals what happens when you form dust grains in a laboratory under conditions similar to those of interstellar space. The cosmic life cycle of dust grains is not well understood we know that in the interstellar medium (ISM), dust is destroyed at a higher rate than it is produced by stellar sources. Since the amount of dust in the ISM stays constant, however, there must be additional sources of dust production besides stars. A team of scientists led by Daniele Fulvio (Pontifical Catholic University of Rio de Janeiro and the Max Planck Institute for Astronomy at the Friedrich Schiller University Jena) have now studied formation mechanisms of dust grains in the lab by mimicking low-temperature ISM conditions and exploring how, under these conditions, carbonaceous materials condense from gas phase to form dust grains. To read more about their results and see additional images, check out the paper below.CitationDaniele Fulvio et al 2017 ApJS 233 14. doi:10.3847/1538-4365/aa9224

  9. THE MEASUREMENT AND DISTRIBUTION OF WOOD DUST

    Directory of Open Access Journals (Sweden)

    Andrea Rosario Proto

    2010-03-01

    Full Text Available In Italy, the woodworking industry presents many issues in terms of occupational health and safety. This study on exposure to wood dust could contribute to the realization of a prevention model in order to limit exposure to carcinogenic agents to the worker. The sampling methodology illustrated the analysis of dust emissions from the woodworking machinery in operation throughout the various processing cycles. The quantitative and qualitative assessment of exposure was performed using two different methodologies. The levels of wood dust were determined according to EN indications and sampling was conducted using IOM and Cyclon personal samplers. The qualitative research of wood dust was performed using an advanced laser air particle counter. This allowed the number of particles present to be counted in real time. The results obtained allowed for an accurate assessment of the quality of the dust emitted inside the workplace during the various processing phases. The study highlighted the distribution of air particles within the different size classes, the exact number of both thin and ultra-thin dusts, and confirmed the high concentration of thin dust particles which can be very harmful to humans.

  10. Pebble Bed Reactor Dust Production Model

    Energy Technology Data Exchange (ETDEWEB)

    Abderrafi M. Ougouag; Joshua J. Cogliati

    2008-09-01

    The operation of pebble bed reactors, including fuel circulation, can generate graphite dust, which in turn could be a concern for internal components; and to the near field in the remote event of a break in the coolant circuits. The design of the reactor system must, therefore, take the dust into account and the operation must include contingencies for dust removal and for mitigation of potential releases. Such planning requires a proper assessment of the dust inventory. This paper presents a predictive model of dust generation in an operating pebble bed with recirculating fuel. In this preliminary work the production model is based on the use of the assumption of proportionality between the dust production and the normal force and distance traveled. The model developed in this work uses the slip distances and the inter-pebble forces computed by the authors’ PEBBLES. The code, based on the discrete element method, simulates the relevant static and kinetic friction interactions between the pebbles as well as the recirculation of the pebbles through the reactor vessel. The interaction between pebbles and walls of the reactor vat is treated using the same approach. The amount of dust produced is proportional to the wear coefficient for adhesive wear (taken from literature) and to the slip volume, the product of the contact area and the slip distance. The paper will compare the predicted volume with the measured production rates. The simulation tallies the dust production based on the location of creation. Two peak production zones from intra pebble forces are predicted within the bed. The first zone is located near the pebble inlet chute due to the speed of the dropping pebbles. The second peak zone occurs lower in the reactor with increased pebble contact force due to the weight of supported pebbles. This paper presents the first use of a Discrete Element Method simulation of pebble bed dust production.

  11. Pebble Bed Reactor Dust Production Model

    International Nuclear Information System (INIS)

    Abderrafi M. Ougouag; Joshua J. Cogliati

    2008-01-01

    The operation of pebble bed reactors, including fuel circulation, can generate graphite dust, which in turn could be a concern for internal components; and to the near field in the remote event of a break in the coolant circuits. The design of the reactor system must, therefore, take the dust into account and the operation must include contingencies for dust removal and for mitigation of potential releases. Such planning requires a proper assessment of the dust inventory. This paper presents a predictive model of dust generation in an operating pebble bed with recirculating fuel. In this preliminary work the production model is based on the use of the assumption of proportionality between the dust production and the normal force and distance traveled. The model developed in this work uses the slip distances and the inter-pebble forces computed by the authors PEBBLES. The code, based on the discrete element method, simulates the relevant static and kinetic friction interactions between the pebbles as well as the recirculation of the pebbles through the reactor vessel. The interaction between pebbles and walls of the reactor vat is treated using the same approach. The amount of dust produced is proportional to the wear coefficient for adhesive wear (taken from literature) and to the slip volume, the product of the contact area and the slip distance. The paper will compare the predicted volume with the measured production rates. The simulation tallies the dust production based on the location of creation. Two peak production zones from intra pebble forces are predicted within the bed. The first zone is located near the pebble inlet chute due to the speed of the dropping pebbles. The second peak zone occurs lower in the reactor with increased pebble contact force due to the weight of supported pebbles. This paper presents the first use of a Discrete Element Method simulation of pebble bed dust production

  12. Simulation of dust-acoustic waves

    International Nuclear Information System (INIS)

    Winske, D.; Murillo, M.S.; Rosenberg, M.

    1998-01-01

    The authors use molecular dynamics (MD) and particle-in-cell (PIC) simulation methods to investigate the dispersion relation of dust-acoustic waves in a one-dimensional, strongly coupled (Coulomb coupling parameter Λ = ratio of the Coulomb energy to the thermal energy = 120) dusty plasma. They study both cases where the dust is represented by a small number of simulation particles that form into a regular array structure (crystal limit) as well as where the dust is represented by a much larger number of particles (fluid limit)

  13. Backscattering Moessbauer spectroscopy of Martian dust

    International Nuclear Information System (INIS)

    Bertelsen, P.; Madsen, M. B.; Binau, C. S.; Goetz, W.; Gunnlaugsson, H. P.; Hviid, S. F.; Kinch, K. M.; Klingelhoefer, G.; Leer, K.; Madsen, D. E.; Merrison, J.; Olsen, M.; Squyres, S. W.

    2005-01-01

    We report on the determination of the mineralogy of the atmospherically suspended Martian dust particles using backscattering 57 Fe Moessbauer spectroscopy on dust accumulated onto the magnets onboard the Mars Exploration Rovers. The spectra can be interpreted in terms of minerals of igneous origin, and shows only limited, if any, amounts of secondary minerals that may have formed in the presence of liquid water. These findings suggest that the dust has formed in a dry environment over long time in the history of the planet.

  14. Dust and radon: the legal implications

    International Nuclear Information System (INIS)

    Van Sittert, J.M.O.

    1990-01-01

    It is known that radon gas is not generally considered to be a major problem when encountered in the working environment. However, in its process of decay, a series of four short lived daughter products are formed. In a dust-laden atmosphere these daughter products, which are ionized readily, attach to the particulate material and when inhaled are deposited in the alveoli of the lungs. Therefore, if respirable dust is controlled, the effects of radon daughters will also be minimized. The legal requirements for dust control in South Africa and their implications are discussed. 1 ill

  15. Is there dust in galactic haloes

    International Nuclear Information System (INIS)

    Greenberg, J.M.; Ferrini, F.; Pisa Univ.; Barsella, B.; Aiello, S.

    1987-01-01

    The ubiquitous presence of dust within the disks of spiral galaxies is well established. The authors predict that the presence of dust in these regions may be revealed in bright edge-on galaxies, especially by using the polarization of the scattered light from the symmetric lanes. The detection of scattered light above the galactic plane may be an indicator that the parent galaxy has not suffered close encounters with other galaxies at least within the timescale required to establish the dust layers. (author)

  16. Residual dust charges in discharge afterglow

    International Nuclear Information System (INIS)

    Coueedel, L.; Mikikian, M.; Boufendi, L.; Samarian, A. A.

    2006-01-01

    An on-ground measurement of dust-particle residual charges in the afterglow of a dusty plasma was performed in a rf discharge. An upward thermophoretic force was used to balance the gravitational force. It was found that positively charged, negatively charged, and neutral dust particles coexisted for more than 1 min after the discharge was switched off. The mean residual charge for 200-nm-radius particles was measured. The dust particle mean charge is about -5e at a pressure of 1.2 mbar and about -3e at a pressure of 0.4 mbar

  17. Effect of non-Maxwellian particle trapping and dust grain charging on dust acoustic solitary waves

    International Nuclear Information System (INIS)

    Rubab, N.; Murtaza, G.; Mushtaq, A.

    2006-01-01

    The role of adiabatic trapped ions on a small but finite amplitude dust acoustic wave, including the effect of adiabatic dust charge variation, is investigated in an unmagnetized three-component dusty plasma consisting of electrons, ions and massive micron sized negatively charged dust particulates. We have assumed that electrons and ions obey (r,q) velocity distribution while the dust species is treated fluid dynamically. It is found that the dynamics of dust acoustic waves is governed by a modified r dependent Korteweg-de Vries equation. Further, the spectral indices (r,q) affect the charge fluctuation as well as the trapping of electrons and ions and consequently modify the dust acoustic solitary wave

  18. Dust storm detection using random forests and physical-based ...

    Indian Academy of Sciences (India)

    arid areas of the Middle. East. Due to the influences of dust aerosols on climate and human daily activities, dust detection plays a crucial role in environmental and climatic studies. Detection of dust storms is critical to accurately under- stand dust ...

  19. Dust analysis on board the Destiny+ mission to 3200 Phaethon

    Science.gov (United States)

    Krüger, H.; Kobayashi, M.; Arai, T.; Srama, R.; Sarli, B. V.; Kimura, H.; Moragas-Klostermeyer, G.; Soja, R.; Altobelli, N.; Grün, E.

    2017-09-01

    The Japanese Destiny+ spacecraft will be launched to the active asteroid 3200 Phaethon in 2022. Among the proposed core payload is an in-situ dust instrument based on the Cassini Cosmic Dust Analyzer. We use the ESA Interplanetary Meteoroid Engineering Model (IMEM), to study detection conditions and fluences of interplanetary and interstellar dust with a dust analyzer on board Destiny+.

  20. Respirable quartz hazard associated with coal mine roof bolter dust

    International Nuclear Information System (INIS)

    Joy, G.J.; Beck, T.W.; Listak, J.M.

    2010-01-01

    Pneumoconiosis has been reported to be increasing among underground coal miners in the Southern Appalachian Region. The National Institute for Occupational Safety and Health conducted a study to examine the particle size distribution and quartz content of dust generated by the installation of roof bolts in mines. Forty-six bulk samples of roof bolting machine pre-cleaner cyclone dump dust and collector box dust were collected from 26 underground coal mines. Real-time and integrated airborne respirable dust concentrations were measured on 3 mining sections in 2 mines. The real-time airborne dust concentrations profiles were examined to identify any concentration changes that might be associated with pre-cleaner cyclone dust discharge events. The study showed that bolter dust is a potential inhalation hazard due to the fraction of dust less than 10 μm in size, and the quartz content of the dust. The pre-cleaner cyclone dust was significantly larger than the collector box dust, indicating that the pre-cleaner functioned properly in removing the larger dust size fraction from the airstream. However, the pre-cleaner dust still contained a substantial amount of respirable dust. It was concluded that in order to maintain the effectiveness of a roof bolter dust collector, periodic removal of dust is required. Appropriate work procedures and equipment are necessary to minimize exposure during this cleaning task. 13 refs., 3 tabs., 2 figs.

  1. Plasma particle lofting : experimental investigation of dust removal force

    NARCIS (Netherlands)

    Heijmans, L.C.J.; Nijdam, S.

    2015-01-01

    Dust is everywhere. Sometimes it's harmless, but sometimes it needs to be removed. Especially in modern optical machinery, dust control can be of vital importance. In this research we look at dust on a surface. We focus on the behaviour under influence of a plasma. The dust particles will stick to a

  2. The physics of wind-blown sand and dust.

    Science.gov (United States)

    Kok, Jasper F; Parteli, Eric J R; Michaels, Timothy I; Karam, Diana Bou

    2012-10-01

    The transport of sand and dust by wind is a potent erosional force, creates sand dunes and ripples, and loads the atmosphere with suspended dust aerosols. This paper presents an extensive review of the physics of wind-blown sand and dust on Earth and Mars. Specifically, we review the physics of aeolian saltation, the formation and development of sand dunes and ripples, the physics of dust aerosol emission, the weather phenomena that trigger dust storms, and the lifting of dust by dust devils and other small-scale vortices. We also discuss the physics of wind-blown sand and dune formation on Venus and Titan.

  3. Experimental Method for Measuring Dust Load on Surfaces in Rooms

    DEFF Research Database (Denmark)

    Lengweiler, Philip; Nielsen, Peter V.; Moser, Alfred

    A new experimental setup to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airborne dust concentration considerably. As a basis for developing methods to eliminate dust-related problems in rooms, there is a n......A new experimental setup to investigate the physical process of dust deposition and resuspension on and from surfaces is introduced. Dust deposition can reduce the airborne dust concentration considerably. As a basis for developing methods to eliminate dust-related problems in rooms......, there is a need for better understanding of the mechanism of dust deposition and resuspension. With the presented experimental setup, the dust load on surfaces in a channel can be measured as a function of the environmental and surface conditions and the type of particles under controlled laboratory conditions....

  4. Inactivation of dust mites, dust mite allergen, and mold from carpet.

    Science.gov (United States)

    Ong, Kee-Hean; Lewis, Roger D; Dixit, Anupma; MacDonald, Maureen; Yang, Mingan; Qian, Zhengmin

    2014-01-01

    Carpet is known to be a reservoir for biological contaminants, such as dust mites, dust mite allergen, and mold, if it is not kept clean. The accumulation of these contaminants in carpet might trigger allergies or asthma symptoms in both children and adults. The purpose of this study is to compare methods for removal of dust mites, dust mite allergens, and mold from carpet. Carpets were artificially worn to simulate 1 to 2 years of wear in a four-person household. The worn carpets were inoculated together with a common indoor mold (Cladosporium species) and house dust mites and incubated for 6 weeks to allow time for dust mite growth on the carpet. The carpets were randomly assigned to one of the four treatment groups. Available treatment regimens for controlling carpet contaminants were evaluated through a literature review and experimentation. Four moderately low-hazard, nondestructive methods were selected as treatments: vacuuming, steam-vapor, Neem oil (a natural tree extract), and benzalkonium chloride (a quaternary ammonium compound). Steam vapor treatment demonstrated the greatest dust mite population reduction (p 0.05) for both physical and chemical methods. The steam-vapor treatment effectively killed dust mites and denatured dust mite allergen in the laboratory environment.

  5. Mineralogy of Interplanetary Dust Particles from the Comet Giacobini-Zinner Dust Stream Collections

    Science.gov (United States)

    Nakamura-Messenger, K.; Messenger, S.; Westphal, A. J.; Palma, R. L.

    2015-01-01

    The Draconoid meteor shower, originating from comet 21P/Giacobini-Zinner, is a low-velocity Earth-crossing dust stream that had a peak anticipated flux on Oct. 8, 2012. In response to this prediction, NASA performed dedicated stratospheric dust collections to target interplanetary dust particles (IDPs) from this comet stream on Oct 15-17, 2012 [3]. Twelve dust particles from this targeted collection were allocated to our coordinated analysis team for studies of noble gas (Univ. Minnesota, Minnesota State Univ.), SXRF and Fe-XANES (SSL Berkeley) and mineralogy/isotopes (JSC). Here we report a mineralogical study of 3 IDPs from the Draconoid collection..

  6. Study on the alternative mitigation of cement dust spread by capturing the dust with fogging method

    Science.gov (United States)

    Purwanta, Jaka; Marnoto, Tjukup; Setyono, Prabang; Handono Ramelan, Ari

    2017-12-01

    The existence of a cement plant impact the lives of people around the factory site. For example the air quality, which is polluted by dust. Cement plant has made various efforts to mitigate the generated dust, but there are still alot of dust fly inground either from the cement factory chimneys or transportation. The purpose of this study was to conduct a review of alternative mitigation of the spread of dust around the cement plant. This study uses research methods such as collecting secondary data which includes data of rain density, the average rains duration, wind speed and direction as well as data of dust intensity quality around PT. Semen Gresik (Persero) Tbk.Tuban plant. A soft Wind rose file is used To determine the wind direction propensity models. The impact on the spread of dust into the environment is determined using secondary data monitoring air quality. Results of the study is that the mitigation of dust around the cement plant is influenced by natural factors, such as the tendency of wind direction, rain fall and rainy days, and the rate of dust emission from the chimney. The alternative means proposed is an environmental friendly fogging dust catcher.

  7. The composition of circumstellar and interstellar dust

    NARCIS (Netherlands)

    Tielens, AGGM; Woodward, CE; Biscay, MD; Shull, JM

    2001-01-01

    A large number of solid dust components have been identified through analysis of stardust recovered from meteorites, and analysis of IR observations of circumstellar shells and the interstellar medium. These include graphite, hydrogenated amorphous carbon, diamond, PAHs, silicon-, iron-, and

  8. He Puff System For Dust Detector Upgrade

    International Nuclear Information System (INIS)

    Rais, B.; Skinner, C.H.; Roquemore, A.L.

    2010-01-01

    Local detection of surface dust is needed for the safe operation of next-step magnetic fusion devices such as ITER. An electrostatic dust detector, based on a 5 cm x 5 cm grid of interlocking circuit traces biased to 50 V, has been developed to detect dust on remote surfaces and was successfully tested for the first time on the National Spherical Torus Experiment (NSTX). We report on a helium puff system that clears residual dust from this detector and any incident debris or fibers that might cause a permanent short circuit. The entire surface of the detector was cleared of carbon particles by two consecutive helium puffs delivered by three nozzles of 0.45 mm inside diameter. The optimal configuration was found to be with the nozzles at an angle of 30o with respect to the surface of the detector and a helium backing pressure of 6 bar.

  9. Surface acoustic wave dust deposition monitor

    Science.gov (United States)

    Fasching, G.E.; Smith, N.S. Jr.

    1988-02-12

    A system is disclosed for using the attenuation of surface acoustic waves to monitor real time dust deposition rates on surfaces. The system includes a signal generator, a tone-burst generator/amplifier connected to a transmitting transducer for converting electrical signals into acoustic waves. These waves are transmitted through a path defining means adjacent to a layer of dust and then, in turn, transmitted to a receiving transducer for changing the attenuated acoustic wave to electrical signals. The signals representing the attenuated acoustic waves may be amplified and used in a means for analyzing the output signals to produce an output indicative of the dust deposition rates and/or values of dust in the layer. 8 figs.

  10. Stochastic Models of Molecule Formation on Dust

    Science.gov (United States)

    Charnley, Steven; Wirstroem, Eva

    2011-01-01

    We will present new theoretical models for the formation of molecules on dust. The growth of ice mantles and their layered structure is accounted for and compared directly to observations through simulation of the expected ice absorption spectra

  11. Obliquely propagating dust-density waves

    International Nuclear Information System (INIS)

    Piel, A.; Arp, O.; Klindworth, M.; Melzer, A.

    2008-01-01

    Self-excited dust-density waves are experimentally studied in a dusty plasma under microgravity. Two types of waves are observed: a mode inside the dust volume propagating in the direction of the ion flow and another mode propagating obliquely at the boundary between the dusty plasma and the space charge sheath. The dominance of oblique modes can be described in the frame of a fluid model. It is shown that the results fom the fluid model agree remarkably well with a kinetic electrostatic model of Rosenberg [J. Vac. Sci. Technol. A 14, 631 (1996)]. In the experiment, the instability is quenched by increasing the gas pressure or decreasing the dust density. The critical pressure and dust density are well described by the models

  12. 25 years of dust acoustic waves

    Science.gov (United States)

    Merlino, Robert L.; Merlino

    2014-12-01

    The dust acoustic wave (DAW) was first discussed by P. K. Shukla in May of 1989 at the First Capri Workshop on Dusty Plasmas. In the past 25 years, the subsequent publication of the linear and nonlinear properties of the DAW (Rao, N. N., Shukla, P. K. and Yu, M. Y. 1990 Planet. Space Sci. 38, 543) has generated and sustained a large body of theoretical and experimental research that has clarified the physics of collective effects in dusty plasmas. A unique feature of the DAW is that it can be observed (literally) using laser illumination and high-speed videography, revealing details of wave-particle interactions at an unprecedented single particle level. This paper attempts to review some of the contributions and extensions of dust acoustic wave physics, as well as identify recent findings that illustrate the potential importance of this dust wave in the agglomeration of dust particles.

  13. Coir dust reinforced recycled polypropylene composites

    International Nuclear Information System (INIS)

    Santos, Bianca B. dos; Costa, Marysilvia F. da; Thire, Rossana M. da S.M.

    2015-01-01

    The environmental impacts caused by disposed plastics encourage the search for new alternatives. Recycling polymers leads to the degradation of their mechanical properties, which can be modified by the addition of fillers. In this paper, recycled polypropylene from plastic cups with 2%, 5% and 10% of coir dust were produced with and without the addition of additives. These composites were characterized by tensile tests, X-ray diffraction, differential scanning calorimetry and scanning electron microscopy on the fracture surface. It was verified the effectiveness of the addition of coir dust in improving the elasticity modulus of recycled polypropylene besides the effectiveness of additives used in promoting the adhesion of the powder to the matrix. However, higher levels of coir dust caused the appearance of air bubbles inside the material, which contributed to its embrittlement. The addition of coir dust promoted a decrease in the degree of polypropylene crystallinity. (author)

  14. Surface System Dust Mitigation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The proposed effort will perform a detailed examination of dust mitigation and tolerance strategies for connections and mechanisms to be employed on the lunar...

  15. House dust mite control measures for asthma

    DEFF Research Database (Denmark)

    Gøtzsche, Peter C.; Johansen, Helle Krogh

    2008-01-01

    BACKGROUND: The major allergen in house dust comes from mites. Chemical, physical and combined methods of reducing mite allergen levels are intended to reduce asthma symptoms in people who are sensitive to house dust mites. OBJECTIVES: To assess the effects of reducing exposure to house dust mite...... antigens in the homes of people with mite-sensitive asthma. SEARCH STRATEGY: PubMed and The Cochrane Library (last searches Nov 2007), reference lists. SELECTION CRITERIA: Randomised trials of mite control measures vs placebo or no treatment in people with asthma known to be sensitive to house dust mites......), the standardised mean difference was 0.00 (95% confidence interval (CI) -0.10 to 0.10). There were no statistically significant differences either in number of patients improved (relative risk 1.01, 95% CI 0.80 to 1.27), asthma symptom scores (standardised mean difference -0.04, 95% CI -0.15 to 0...

  16. The Marriage of Gas and Dust

    Science.gov (United States)

    Price, D. J.; Laibe, G.

    2015-10-01

    Dust-gas mixtures are the simplest example of a two fluid mixture. We show that when simulating such mixtures with particles or with particles coupled to grids a problem arises due to the need to resolve a very small length scale when the coupling is strong. Since this is occurs in the limit when the fluids are well coupled, we show how the dust-gas equations can be reformulated to describe a single fluid mixture. The equations are similar to the usual fluid equations supplemented by a diffusion equation for the dust-to-gas ratio or alternatively the dust fraction. This solves a number of numerical problems as well as making the physics clear.

  17. Nanotube Electrodes for Dust Mitigation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Dust mitigation is critical to the survivability of vehicle and infrastructure components and systems and to the safety of astronauts during EVAs and planetary...

  18. Solar-Panel Dust Accumulation and Cleanings

    Science.gov (United States)

    2005-01-01

    Air-fall dust accumulates on the solar panels of NASA's Mars Exploration Rovers, reducing the amount of sunlight reaching the solar arrays. Pre-launch models predicted steady dust accumulation. However, the rovers have been blessed with occasional wind events that clear significant amounts of dust from the solar panels. This graph shows the effects of those panel-cleaning events on the amount of electricity generated by Spirit's solar panels. The horizontal scale is the number of Martian days (sols) after Spirit's Jan. 4, 2005, (Universal Time) landing on Mars. The vertical scale indicates output from the rover's solar panels as a fraction of the amount produced when the clean panels first opened. Note that the gradual declines are interrupted by occasional sharp increases, such as a dust-cleaning event on sol 420.

  19. Investigations of Wind/WAVES Dust Impacts

    Science.gov (United States)

    St Cyr, O. C.; Wilson, L. B., III; Rockcliffe, K.; Mills, A.; Nieves-Chinchilla, T.; Adrian, M. L.; Malaspina, D.

    2017-12-01

    The Wind spacecraft launched in November 1994 with a primary goal to observe and understand the interaction between the solar wind and Earth's magnetosphere. The waveform capture detector, TDS, of the radio and plasma wave investigation, WAVES [Bougeret et al., 1995], onboard Wind incidentally detected micron-sized dust as electric field pulses from the recollection of the impact plasma clouds (an unintended objective). TDS has detected over 100,000 dust impacts spanning almost two solar cycles; a dataset of these impacts has been created and was described in Malaspina & Wilson [2016]. The spacecraft continues to collect data about plasma, energetic particles, and interplanetary dust impacts. Here we report on two investigations recently conducted on the Wind/WAVES TDS database of dust impacts. One possible source of dust particles is the annually-recurring meteor showers. Using the nine major showers defined by the American Meteor Society, we compared dust count rates before, during, and after the peak of the showers using averaging windows of varying duration. However, we found no statistically significant change in the dust count rates due to major meteor showers. This appears to be an expected result since smaller grains, like the micron particles that Wind is sensitive to, are affected by electromagnetic interactions and Poynting-Robertson drag, and so are scattered away from their initial orbits. Larger grains tend to be more gravitationally dominated and stay on the initial trajectory of the parent body so that only the largest dust grains (those that create streaks as they burn up in the atmosphere) are left in the orbit of the parent body. Ragot and Kahler [2003] predicted that coronal mass ejections (CMEs) near the Sun could effectively scatter dust grains of comparable size to those observed by Wind. Thus, we examined the dust count rates immediately before, during, and after the passage of the 350 interplanetary CMEs observed by Wind over its 20+ year

  20. Ice nucleation properties of mineral dusts

    OpenAIRE

    Steinke, Isabelle

    2013-01-01

    Ice nucleation in clouds has a significant impact on the global hydrological cycle as well as on the radiative budget of the Earth. The AIDA cloud chamber was used to investigate the ice nucleation efficiency of various atmospherically relevant mineral dusts. From experiments with Arizona Test Dust (ATD) a humidity and temperature dependent ice nucleation active surface site density parameterization was developed to describe deposition nucleation at temperatures above 220 K. Based...