scholarly journals Assessment of explosion risk for wood dust in a ventilation-dust separation installation, by determining the concentration of total dust in suspension inside of the installation

2022 ◽  
Vol 354 ◽  
pp. 00006
Author(s):  
Marius Kovacs ◽  
Lorand Toth ◽  
Sorin Simion
Keyword(s):  
Textile Industry ◽  
Wood Products ◽  
Wood Dust ◽  
Explosion Hazard ◽  
Minimum Ignition Energy ◽  
Bag Filter ◽  
Cloud Particle ◽  
Measured Concentration ◽  
Explosion Pressure ◽  
Explosion Limit

Most of combustible dusts present both fire and explosion hazard. Explosion may occur at certain concentrations of dust mixed with air and in the presence of an ignition source. The threat posed by this real danger was confirmed by the events that took place in economic units such as: feed factories, wood products, textile industry, steel, etc. Among the parameters of explosiveness of combustible dust, which can cause an explosion, we mention: maximum explosion pressure, lower explosion limit, explosive index, minimum ignition energy, electrical resistivity of dust, minimum ignition temperature of dust layer and cloud, particle size and concentration of dust in suspension. The current paper presents the results of determinations of combustible wood dust concentrations, performed at an important economic unit, manufacturing veneer and wood panels, at a dusting ventilation installation composed of fan, cyclone and textile filter. These determinations were made in the pipe connecting the fan and the bag filter, to assess possible danger of explosion in the pipe, by relating the measured concentration to the lower explosion limit (concentration of wood dust).

Effects of moisture content on explosion characteristics of incense dust in incense factory

2021 ◽  
Author(s):  
Shun-Chieh Chang ◽  
Yu-Chi Cheng ◽  
Xin-Hai Zhang ◽  
Chi-Min Shu
Keyword(s):  
Moisture Content ◽  
Control Group ◽  
Dust Explosion ◽  
Minimum Ignition Energy ◽  
Operating Environment ◽  
Cultural Expression ◽  
Explosion Pressure ◽  
Dust Dispersion ◽  
Explosion Limit ◽  
Effect Of Moisture

AbstractIncense is an indispensable material with religion and life in Asia. It is also a bridge of cultural expression and inheritance. Because the operating environment concentration of dust generated during the production process is considerable, most of the research pertaining to the hazard of incense factories has investigated air pollution, such as PM2.5, PM10, and VOCs. However, the production of incense causes dust dispersion, high temperature from ovens, and static electricity generated by friction. It can all possibly lead a dust explosion. To prevent and alleviate hazard from re-occurring, we used sandalwood dust at an incense factory in Taiwan, measured the effect of moisture content on the explosion parameters under normal conditions by 20-L apparatus, and used the oven to diminish its moisture content to 0%, 10.0%, and 15.0% as a control group to analyze the explosion characteristics at the different moisture contents, such as maximum explosion pressure and explosion limit. The results showed that the minimum ignition energy of dry dust was 30 mJ. Beyond doubt, incense factories face potential explosion hazards. The above results could be evaluated by the most dangerous range to avoid incense dust in this range at the workplace, lessening hazards caused by a dust explosion. The effect of moisture content on the suppression of the dust explosion was explored.

scholarly journals The Fire and Explosion Hazard of Coloured Powders Used during the Holi Festival

2021 ◽  
Vol 18 (21) ◽  
pp. 11090
Author(s):  
Bożena Kukfisz ◽  
Robert Piec
Keyword(s):  
Dust Cloud ◽  
Explosion Hazard ◽  
Minimum Ignition Energy ◽  
Health And Environmental Effects ◽  
Dust Layer ◽  
Respiratory Problems ◽  
Explosion Pressure ◽  
Fire And Explosion ◽  
Explosive Properties ◽  
Holi Festival

During the world-famous Holi festival, people throw and smear each other with a colored powder (Holi color, Holi powder, Gulal powder). Until now, adverse health and environmental effects (skin and eye irritation, air pollution, and respiratory problems) have been described in the available literature. However, the literature lacks data on the flammable and explosive properties of these powders during mass events, despite the fact that burns, fires, and explosions during the Holi festival have taken place many times. The aim of the article is to present the fire and explosion parameters of three currently used Holi dust and cornflour dust types as reference dust. The minimum ignition temperature of the dust layer and dust cloud, the maximum explosion pressure and its maximum rate of growth over time, the lower explosion limit, the limit of oxygen concentration, and the minimum ignition energy were determined. Tests confirmed that the currently available Holi powders should be classified as flammable dusts and low-explosive dusts. The likelihood of a fire or explosion during mass incidents involving a Holi dust-air mixture is high.

scholarly journals Sensitivity to ignition by electrostatic discharge of explosive dust / air

2019 ◽  
Vol 290 ◽  
pp. 12011 ◽  
Author(s):  
Dan Gabor ◽  
Emilian Ghicioi ◽  
Mihaela Părăian ◽  
Niculina Vătavu ◽  
Florin Adrian Păun ◽  
...  
Keyword(s):  
Electrostatic Discharge ◽  
Electrostatic Charge ◽  
Explosion Hazard ◽  
Explosive Mixture ◽  
Ignition Energy ◽  
Minimum Ignition Energy ◽  
Electrostatic Discharges ◽  
Industrial Sectors ◽  
Surrounding Atmosphere

In industrial sectors that use, process, transport or store, substances such as combustible dusts could exist some workplaces with explosion hazard due to the possibility of dust/air explosive formation and ignition, both inside the installations and in the surrounding atmosphere. Methods and means of protection aim to prevent the development of explosive atmospheres, followed by preventing the occurrence of ignition sources and then limiting the effects of explosions. To assess the risk of ignition of the explosive atmosphere, there must be known first of all, the explosive atmosphere’s sensitivity to ignition by electrostatic discharge, respectively, the minimum ignition energy of the explosive mixture, afterwards being required an analysis on the possibilities of formation and discharge of electrostatic charge. For the most common combustible dusts, the minimum ignition energy is given, but for new types of flammable substances this parameter defining the sensitivity to ignition of the mixture by electrostatic discharges must be determined. The paper presents the results of research carried out in order to develop the methods and standards for determining the minimum ignition energy of the combustible dust / air mixture and of the methods for the assessment of the risk of ignition of the dust/air explosive atmosphere by electrostatic discharge.

scholarly journals Analysis of the Effect of the Biomass Torrefaction Process on Selected Parameters of Dust Explosivity

Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3525
Author(s):  
Marcin Bajcar ◽  
Bogdan Saletnik ◽  
Grzegorz Zaguła ◽  
Czesław Puchalski
Keyword(s):  
Agricultural Waste ◽  
Pressure Rise ◽  
Explosion Hazard ◽  
Storage Process ◽  
Fuel Production ◽  
Explosion Pressure ◽  
Energy Material ◽  
Biomass Processing ◽  
Risk Research ◽  
Research Findings

This article presents the findings of a study investigating the explosion and combustion parameters of dust from the raw biomass of wheat straw and energy willow and from the products of biomass torrefaction generated at temperatures ranging from 220 to 300 °C. Agricultural waste and energy crops and their modifications, e.g., in the torrefaction process, did not find a place in explosive risk research, which the authors decided to present in their work. The study was designed to estimate explosion hazard during the processing of the materials into fuels and during the storage process. The measurements recorded a maximum explosion pressure Pmax in the case of dust from biomass ranging from 7.2 to 7.3 bar and for dust from torrefied materials amounting to 7.5–9.2 bar, and a maximum rate of pressure rise over time (dp/dt)max in raw biomass ranging from 201.4 to 261.3 bar/s and in torrefied materials amounting to 209.6–296.6 bar/s. The estimated explosion index Kstmax for raw biomass was 55–72 m*bar/s and for torrefied materials was in the range from 57 to 81 m*bar/s. In the results, the authors present values for specific types of fuel which differ significantly depending on the type of biomass. The research findings show that the torrefaction process used in fuel production is not associated with a significantly greater risk of explosion and the materials obtained may safely be used as an alternative to conventional solid fuels. Given the growing interest in the use of biomass and in the variety of biomass processing methods for energy-related purposes, it seems there is a need for research to develop appropriate guidelines and for effective practices to be introduced in the energy industry in order to ensure the safety of the processes used in the production of novel fuels especially in small installations converting these materials into more efficient energy material.

scholarly journals Explosion Pressure and Minimum Explosible Concentration Properties of Metal Sulfide Ore Dust Clouds

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Yun-zhang Rao ◽  
Chang-shun Tian ◽  
Wei Xu ◽  
Chun-yu Xiao ◽  
Bo-yun Yuan ◽  
...  
Keyword(s):  
Particle Size ◽  
Sulfur Content ◽  
Metal Sulfide ◽  
Explosion Hazard ◽  
Factors Affecting ◽  
Explosion Pressure ◽  
Dust Clouds ◽  
Sulfide Ore ◽  
Before And After ◽  
Concentration Properties

The explosion pressure and minimum explosible concentration (MEC) properties of metal sulfide ore dust clouds are valuable for the prevention and control of metal sulfide ore dust explosions. In this study, a 20 L explosion sphere vessel was used to investigate the effect of sulfur content, particle size, and concentration on the explosion pressure and minimum explosible concentration of metal sulfide ore dust clouds. Four samples with different sulfur contents were selected (30%–40%, 20%–30%, 10%–20%, and 0%–10%). Before and after the explosion, samples were tested by X-ray diffraction. The results indicate that the metal sulfide ore dust is explosive dust with St1 grade explosion pressure. With an increase in concentration, the maximum explosion pressure increased at first and then decreased. With an increase in sulfide content, the explosion pressure of metal sulfide ore dust increased, while the minimum explosible concentration decreased. As particle size decreased, the MEC also decreased. The sulfur content, particle size, and concentration of metal sulfide ore dust were the main factors affecting the explosion hazard.

scholarly journals Experimental Study on Multiple Explosions during the Development and Utilization of Oil Shale Dust

2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Bo Liu ◽  
Yansong Zhang ◽  
Yuyuan Zhang ◽  
Jinshe Chen ◽  
Xiangbao Meng
Keyword(s):  
Oil Shale ◽  
Pressure Rise ◽  
Minimum Ignition Energy ◽  
Sem Images ◽  
Combustion Heat ◽  
Explosion Pressure ◽  
Propagation Behavior ◽  
Spherical Tank ◽  
Development And Utilization ◽  
The Difference

Oil shale is a kind of high-combustion heat mineral; in the process of exploitation, storage, and utilization, oil shale dust has the risk of explosion. The explosion characteristics and flame propagation behavior of oil shale dust are worth studying. The difference between the multiple explosion behaviors of oil shale dust was investigated with the use of a 20 L explosive spherical tank and a dust MIE experimental device. The explosion characteristics and microstructure changes of the explosive products in multiple explosions were examined. The experimental results show that the maximum explosion pressure (Pmax) dropped, and simultaneously, the minimum ignition energy (MIE), the explosion time (t), and the maximum rate of pressure rise (dp/dtmax) increased as the explosions continued. Furthermore, the oil shale continued exploding until the third explosion. Some original oil shale dust (OOSD) and explosive residues were analyzed using a scanning electron microscope (SEM) and Fourier transform infrared (FT-IR) spectrometer. The SEM images of the explosive residues indicate a high fragmentation degree and well-developed pore structure during the entire multiexplosion process. Oxygen-containing functional groups, the aliphatic C-H bond, and the aromatic C-H bond in oil shale dust all participated in the oil shale dust explosion process.

RISK ASSESSMENT IN TEXTILE AND WOOD, PROCESSING INDUSTRY

2006 ◽  
Vol 13 (02) ◽  
pp. 115-125 ◽  
Author(s):  
KARIN REINHOLD ◽  
PIIA TINT ◽  
GUNNAR KIIVET
Keyword(s):  
Risk Assessment ◽  
Working Conditions ◽  
Textile Industry ◽  
Assessment Method ◽  
Wood Dust ◽  
Stage Model ◽  
Processing Industry ◽  
Wood Processing ◽  
Risk Assessment Method ◽  
Load Noise

The working conditions in textile and wood processing industries have been investigated using a simple risk assessment method and questionnaires worked out for the purpose. A simple/flexible risk assessment method (beginning with a two-stage model that could be enlarged into a six-stage model) is worked out by the authors (Tint & Kiivet) and the implementation possibilities are presented. It is necessary to increase interest from the side of employers for using the method and analyzing the work environment with the aim of improvement implementations. The main complaints in textile industry are high temperature in the workroom, bad ventilation, intense work and the dependence of workers' work results from the others. The main risk factors in wood processing industry are hazardous tools and equipment, also heavy physical load, noise, wood dust and odors of chemicals originating from polishes.

scholarly journals Assessment of the performance of the inter-arrival time algorithm to identify ice shattering artifacts in cloud particle probe measurements

2015 ◽  
Vol 8 (2) ◽  
pp. 761-777 ◽  
Author(s):  
A. Korolev ◽  
P. R. Field
Keyword(s):  
Particle Size ◽  
Arrival Time ◽  
Time Algorithm ◽  
Sample Volume ◽  
Ice Crystals ◽  
Cloud Particle ◽  
Measured Concentration ◽  
Arrival Times ◽  
Microphysical Properties ◽  
The Impact

Abstract. Shattering presents a serious obstacle to current airborne in situ methods of characterizing the microphysical properties of ice clouds. Small shattered fragments result from the impact of natural ice crystals with the forward parts of aircraft-mounted measurement probes. The presence of these shattered fragments may result in a significant overestimation of the measured concentration of small ice crystals, contaminating the measurement of the ice particle size distribution (PSD). One method of identifying shattered particles is to use an inter-arrival time algorithm. This method is based on the assumption that shattered fragments form spatial clusters that have short inter-arrival times between particles, relative to natural particles, when they pass through the sample volume of the probe. The inter-arrival time algorithm is a successful technique for the classification of shattering artifacts and natural particles. This study assesses the limitations and efficiency of the inter-arrival time algorithm. The analysis has been performed using simultaneous measurements of two-dimensional (2-D) optical array probes with the standard and antishattering "K-tips" collected during the Airborne Icing Instrumentation Experiment (AIIE). It is shown that the efficiency of the algorithm depends on ice particle size, concentration and habit. Additional numerical simulations indicate that the effectiveness of the inter-arrival time algorithm to eliminate shattering artifacts can be significantly restricted in some cases. Improvements to the inter-arrival time algorithm are discussed. It is demonstrated that blind application of the inter-arrival time algorithm cannot filter out all shattered aggregates. To mitigate against the effects of shattering, the inter-arrival time algorithm should be used together with other means, such as antishattering tips and specially designed algorithms for segregation of shattered artifacts and natural particles.

scholarly journals Determination of the Explosion Characteristics of Wheat Flour

2017 ◽  
Vol 25 (40) ◽  
pp. 9-16
Author(s):  
Richard Kuracina ◽  
Zuzana Szabová ◽  
Denisa Pangrácová ◽  
Karol Balog
Keyword(s):  
Wheat Flour ◽  
Maximum Rate ◽  
Pressure Rise ◽  
Explosion Pressure ◽  
Maximum Explosion Pressure ◽  
Dust Clouds ◽  
Maximum Value ◽  
Flour Dust ◽  
Explosion Limit

Abstract The article deals with the measurement of explosion characteristics of wheat flour. 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, 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 and LEL according to STN EN 14034-3+A1:2011 Determination of explosion characteristics of dust clouds: Determination of the lower explosion limit LEL of dust clouds. The testing of explosions of wheat flour dust clouds showed that the maximum value of the pressure was reached at the concentrations of 600 g/m3 and its value is 8.32 bar/s. The fastest increase of pressure was observed at the concentration of 750 g/m3 and its value was 54.2 bar/s.

Sign in / Sign up

Export Citation Format

Share Document