scholarly journals Evaluation of Marblewood Dust’s (Marmaroxylon racemosum) Effect on Ignition Risk

2021 ◽  
Vol 11 (15) ◽  
pp. 6874
Author(s):  
Miroslava Vandličkova ◽  
Iveta Markova ◽  
Katarina Holla ◽  
Stanislava Gašpercová
Keyword(s):  
Particle Size ◽  
Dust Particles ◽  
Wood Dust ◽  
Sieve Analysis ◽  
Granulometric Analysis ◽  
Analysis Measurement ◽  
Risk Research ◽  
Minimum Ignition Temperature ◽  
The Impact

The paper deals with the selected characteristics, such as moisture, average bulk density, and fraction size, of tropical marblewood dust (Marmaroxylon racemosum) that influence its ignition risk. Research was focused on sieve analysis, granulometric analysis, measurement of moisture level in the dust, and determination of the minimum ignition temperatures of airborne tropical dust and dust layers. Samples were prepared using a Makita 9556CR 1400W grinder and K36 sandpaper for the purpose of selecting the percentages of the various fractions (<63, 63, 71, 100, 200, 315, 500 μm). The samples were sized on an automatic vibratory sieve machine Retsch AS 200. More than 65% of the particles were determined to be under 100 μm. The focus was on microfractions of tropical wood dust (particles with a diameter of ≤100 µm) and on the impact assessment of particle size (particle size <100 µm) on the minimum ignition temperatures of airborne tropical dust and dust layers. The minimum ignition temperature of airborne marblewood dust decreased with the particle size to the level of 400 °C (particle size 63 μm).

scholarly journals Ignition of Deposited Wood Dust Layer by Selected Sources

2020 ◽  
Vol 10 (17) ◽  
pp. 5779 ◽  
Author(s):  
Ivana Tureková ◽  
Iveta Marková
Keyword(s):  
Ignition Temperature ◽  
Ignition Time ◽  
Dust Sample ◽  
Spatial Arrangement ◽  
Quercus Petraea ◽  
Ignition Source ◽  
Dust Particles ◽  
Wood Dust ◽  
Sieve Analysis ◽  
Ignition Process

The main waste of wood sanding technology is wood dust. The formation of wood dust affects its behaviour. Wood dust can be in a turbulent form and behaves explosively or in a settled form where it becomes flammable. Dust particles are barely detectable by the naked eye, wood dust still presents substantial health, safety, fire and explosion risks to employees. This article deals with the evaluation of ignition temperature and surface temperature of deposited wood dust samples by selected ignition sources. The influence of selected physical properties of wood dust, the size of the contact area between the ignition source and the combustible material, the spatial arrangement during the ignition and the application time of the ignition source are analysed. The paper describes the behaviour of a 15 mm deposited layer of wood dust of spruce (Picea abies L.), beech (Fagus silvatica L.). oak (Quercus petraea Liebl.) caused by three potential ignition sources—a hot surface, an electric coil and a smouldering cigarette. Prior to the experimental determination of the ignition temperature, dust moisture content which did not significantly affect the ignition phase of the samples, as well as sieve analysis of tested samples were determined. The lowest minimum ignition temperature on the hot plate, as an important property of any fuel, because the combustion reaction of the fuel becomes self-sustaining only above this temperature, was reached by the oak dust sample (280 °C), the highest by the spruce dust sample (300 °C). The ignition process of wood dust was comparable in all samples, differing in the ignition time and the area of the thermally degraded layer. The least effective ignition source was a smouldering cigarette.

Machine vision based particle size and size distribution determination of airborne dust particles of wood and bark pellets

2009 ◽  
Vol 196 (2) ◽  
pp. 202-212 ◽  
Author(s):  
C. Igathinathane ◽  
S. Melin ◽  
S. Sokhansanj ◽  
X. Bi ◽  
C.J. Lim ◽  
...  
Keyword(s):  
Particle Size ◽  
Machine Vision ◽  
Size Distribution ◽  
Dust Particles ◽  
Airborne Dust

scholarly journals Influence of Grit Size and Wood Species on the Granularity of Dust Particles during Sanding

2020 ◽  
Vol 10 (22) ◽  
pp. 8165
Author(s):  
Marta Pędzik ◽  
Kinga Stuper-Szablewska ◽  
Maciej Sydor ◽  
Tomasz Rogoziński
Keyword(s):  
Particle Size ◽  
Grit Size ◽  
Dust Particles ◽  
Wood Dust ◽  
Particle Sizes ◽  
Respirable Fraction ◽  
Dust Fraction ◽  
The Mean ◽  
Oak Ash

Wood dust poses a threat to the health of employees and the risk of explosion and fire, accelerates the wear of machines, worsens the quality of processing, and requires large financial outlays for its removal. The aim of this study was to investigate the extent to which the grit size of sandpaper influences the size of the wood dust particles and the proportion of the finest particles which, when dispersed in the air, may constitute the respirable fraction. Six species of hardwood (beech, oak, ash, hornbeam, alder, and walnut), and three species of softwood (larch, pine, and spruce) were used in the research. While sanding the samples under the established laboratory conditions, the following were measured for two types of sandpapers (grit sizes P60 and P180): mean arithmetic particle size of dust and finest dust particles content (<10 µm). Based on the obtained results, we found that the largest dust particle sizes were obtained for alder, pine, and spruce; the smallest size of dust particles during sanding with both sandpapers was obtained for beech, hornbeam, oak, ash, larch, and walnut. The mean arithmetic particle sizes ranged from 327.98 µm for pine to 104.23 µm for hornbeam. The mean particle size of the dust obtained with P60 granulation paper was 1.4 times larger than that of the dust obtained with P180 granulation sandpaper. The content of the finest dust particles ranged from 0.21% for pine (P60 sandpaper) to 12.58% for beech (P180 sandpaper).The type of wood (hardwood or softwood) has a significant influence on the particle size and the content of the finest dust fraction.

scholarly journals An Impact Mass-Spectrometer for the Halley-Probe

1980 ◽  
Vol 90 ◽  
pp. 275-276
Author(s):  
G. Braun ◽  
E. Grün ◽  
J. Kissel ◽  
N. Pailer
Keyword(s):  
Impact Ionization ◽  
Target Material ◽  
Dust Particles ◽  
Ionization Mass ◽  
Cometary Dust ◽  
First Results ◽  
A Charge ◽  
Comet Halley ◽  
The Impact

The relative speed between Comet Halley and the presently planned Halley Probe will be approx. 55 km/s. At such a speed the method of impact ionization mass-spectrometry is perfectly suited to analysing cometary dust particles with masses from 10−16g to 10−10g. First results are reported by Dalmann et al. If a micrometeoroid hits the sensitive target, ions from both particle and target material are produced. The total number of ions is registered with a charge-sensitive amplifier and this signal Q allows the determination of the particle mass m (Q ∼ m). By an electric potential difference of 3 kV, ions are drawn into a field-free drift-tube. The ions are separated in time in the TOF-Spectrometer due to their different masses. The mass spectrum is registered as output current of the particle multiplier at the end of the TOF-tube. It gives information about the chemical composition of the detected particle. Characteristics of such spectra recorded with the Impact-Spectrometer currently used in the laboratory are the following: a) mass resolution m/Δm > 100 at 23 amu, b) flight-time (t ∼ 14 μs at 100 amu; the corresponding Δt ∼ 70 ns between 99 and 100 amu).

150-212μm Dust Particles on the Reliability of Electrical Contact in Static Conditions

2013 ◽  
Vol 442 ◽  
pp. 17-21
Author(s):  
Quan Yin ◽  
Sheng Chun Liu ◽  
Liang Jun Xu
Keyword(s):  
Particle Size ◽  
Contact Resistance ◽  
Electrical Contact ◽  
Dust Particles ◽  
Particle Size Range ◽  
Contact Materials ◽  
Static Contact ◽  
Electrical Contact Materials ◽  
Static Conditions ◽  
The Impact

Dust particles from the air in the electrical contact caused more and more problems. To a large extent reduce the reliability of the system. In order to study the impact of these issues, we need to analyze and discuss the dust particles on contact performance of electrical contact materials. In this paper, under static conditions with 150-212μm of the silica particles analyzed and discussed, represented by the pressure difference, particle size, being suppressed will lead to a different location of the static contact resistance and analysis of particle size of the scope of what the content of easily crushed. Experimental results show that the particle size and the location of the different particles are pressed, will make a change in contact resistance, another analysis gives easily be crushed particle size range is 150-300μm.

Acoustical Behavior of Treated Wood Dust-Filler for Polymer Foam Composite

2013 ◽  
Vol 465-466 ◽  
pp. 1039-1043 ◽  
Author(s):  
Shafizah Sa'adon ◽  
Anika Zafiah Mohd Rus
Keyword(s):  
Particle Size ◽  
Absorption Coefficient ◽  
Pore Size ◽  
Sound Absorption ◽  
Treated Wood ◽  
Sound Absorption Coefficient ◽  
Dust Particles ◽  
Wood Dust ◽  
Polymer Foam ◽  
Foam Composite

Wood dust filler-polymer foam composite has been studied and proved to have ability to absorb sound. In this study, treated rubber and Meranti wood dust named as RA and MA respectively was use as the filler. This study was developed to compare the behavior of sound absorption based on treated filler and particle size of wood dust. By choosing the size of 355 and 710 μm, three different percentages has been selected which is 10%, 15% and 20% for both type of wood dust. These samples has been tested by using Impedance Tube test for sound absorption coefficient (α) measurement and Noise Reduction Coefficient measurement (NRC) and Scanning Electron Microscopy (SEM) to determine the diameter of pore for selected size and type of wood dust-polymer foam composite. The pore size and structure was influence the sound absorption behavior of each sample. 355 μm-polymer foam composite of every percentage loading shows the uniform pore structure as compared to 710 μm of particle size. NRC results shows that increasing pore size has decrease the NRC value. It is therefore, concluded that the sound absorption coefficient for eachsound absorbing material, with different sizes of wood dust particles, types of wood dust and the percentages of wood dust loading in polymer foam matrix effect the sound absorption behavior.

scholarly journals Study of Fire Characteristics of Industrial Dust

2019 ◽  
Vol 27 (44) ◽  
pp. 49-56
Author(s):  
Zuzana Szabová ◽  
Richard Kuracina
Keyword(s):  
Particle Size ◽  
Ignition Temperature ◽  
Dust Layer ◽  
Industrial Dust ◽  
Explosion Limit ◽  
Minimum Ignition Temperature ◽  
Fire Characteristics ◽  
Hot Surface

Abstract The article deals with the determination of fire characteristics of industrial dust samples. Particle size granulometry and determination of explosion parameters according to EN 14034 (Lower Explosion Limit LEL, Pmax, Kst) are presented. The minimum ignition temperatures of the dust layer and dispersed dust from the hot surface according to EN ISO / IEC 80079-20-2: 2016 were measured. It was found that LEL is 60 g.m−3, Pmax is 8.61 bar, and Kst is 89 bar.s−1.m. The minimum ignition temperature (MIT) of dust layer is 280 ° C and the minimum ignition temperature of dispersed dust is 400 ° C.

scholarly journals Study of Explosion Characteristics of Wood Dust Clouds in Dependence of the Particle Size Distribution

2017 ◽  
Vol 25 (40) ◽  
pp. 17-23 ◽  
Author(s):  
Richard Kuracina ◽  
Zuzana Szabová ◽  
Matej Menčík
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Maximum Rate ◽  
Pressure Rise ◽  
Wood Dust ◽  
Explosion Pressure ◽  
Maximum Explosion Pressure ◽  
Dust Clouds

Abstract The article deals with the measurement of explosion characteristics of wood dust. The measurements were carried out according to STN EN 14034-1+A1:2011 Determination of explosion characteristics of dust clouds. Part 1: Determination of the maximum explosion pressure pmax of dust clouds and the maximum rate of explosion pressure rise according to STN EN 14034-2+A1:2012 Determination of explosion characteristics of dust clouds - Part 2: Determination of the maximum rate of explosion pressure rise (dp/dt)max of dust clouds. On the basis of measurements, we found that the distribution of the particles has a significant impact on the parameters of wood dust samples.

scholarly journals Tropical Wood Dusts—Granulometry, Morfology and Ignition Temperature

2020 ◽  
Vol 10 (21) ◽  
pp. 7608
Author(s):  
Miroslava Vandličková ◽  
Iveta Marková ◽  
Linda Makovická Osvaldová ◽  
Stanislava Gašpercová ◽  
Jozef Svetlík ◽  
...  
Keyword(s):  
Ignition Temperature ◽  
Dust Particles ◽  
Wood Dust ◽  
Particle Sizes ◽  
Explosive Mixture ◽  
Tropical Wood ◽  
Granulometric Analysis ◽  
Tropical Woods ◽  
Automatic Mesh ◽  
Dipteryx Odorata

The article considers the granulometric analysis of selected samples of tropical wood dust from cumaru (Dipteryx odorata), padauk (Pterocarpus soyauxii), ebony (Diospyros crassiflora), and marblewood (Marmaroxylon racemosum) using a Makita 9556CR 1400 W grinder and K36 sandpaper, for the purpose of selecting the percentages of the various fractions (<63; 63; 71; 200; 315; 500 μm) of wood dust samples. Tropical wood dust samples were made using a hand orbital sander Makita 9556CR 1400 W, and sized using the automatic mesh vibratory sieve machine Retsch AS 200 control. Most dust particles (between 50–79%) from all wood samples were under 100 μm in size. This higher percentage is associated with the risk of inhaling the dust, causing damage to the respiratory system, and the risk of a dust-air explosive mixture. Results of granulometric fractions contribution of tropical woods sanding dust were similar. Ignition temperature was changed by particle sizes, and decreased with a decrease in particle sizes. We found that marblewood has the highest minimum ignition temperature (400–420 °C), and padauk has the lowest (370–390 °C).

scholarly journals Wpływ rumoszu drzewnego na granulometrię osadów korytowych

2018 ◽  
Vol 27 (1) ◽  
pp. 42-56
Author(s):  
Karol Plesiński
Keyword(s):  
Woody Debris ◽  
Size Composition ◽  
Efficiency Coefficient ◽  
River Bed ◽  
Granulometric Analysis ◽  
Bed Material ◽  
The Impact ◽  
The Relationship ◽  
Spearman’S Correlation

The aim of paper is to investigate the impact of woody debris deposited on the river bed on the granulometry of the bed material. The analysis included upstream and downstream sides of the investigated woody debris. The investigations comprised determination of the geometric dimensions of the analyzed wood deposits, determination of the granulometric composition of the bed material in the area of deposition of woody debris, determination of the range of influence of the investigated woody debris on the bed material and determination of the relationship between the geometric dimensions of the woody debris and the extent of their impact on the bed material. The granulometric analysis was conducted using the conventional sieving method. The extent of the influence of woody debris was determined on the basis of the Nash’s-Sutcliffe’s efficiency coefficient. The dependence of the extent of wood influence and the dimensions of the investigated woody debris was determined on the basis of the Spearman’s correlation coefficient. It was found that the woody debris deposited on the bed of the Raba river affects the granulometry of the bed material on both the upstream and downstream sides. The study also showed that the extent of the impact on the grain-size composition of the bed material on the downstream sides of the woody debris is determined to a large extent by the height of the deposited woody debris.

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