Research on Gas Temperature Affect on Pharmacy Dust Explosion Pressure in Transport Pipeline

2013 ◽  
Vol 634-638 ◽  
pp. 3618-3621
Author(s):  
Xiao Liang Zhang
Keyword(s):  
Combustion Velocity ◽  
Pressure Change ◽  
Velocity Model ◽  
Dust Explosion ◽  
Gas Temperature ◽  
Explosion Pressure ◽  
Pressure Pipeline ◽  
Pressure Maximum ◽  
Potassium Clavulanate ◽  
Explosion Experiment

This document has firstly been established explosion combustion velocity model in trasport pipeline, analysis on gas temperature effect on dust explosion strength. Gas temperature at 40 °C~ 60°C on the potassium clavulanate mixed dust explosion experiment are studied in the pipeline. The experiment indicates that dust explosion pressure change as gas temperature at 40°C, 46.3°C, 50.5 °C, 54.1°C, 55.8°C, 59.7°C, The studies show that gas temperature rise causes dust explosion pressure pipeline center development,bring piston wave phenomenon.Dust explosion pressure maximum value is get up to 375kPa and negative pressure value is 875kPa.

scholarly journals Preliminary study on the tea dust explosion: the effect of tea dust size

2019 ◽  
Vol 255 ◽  
pp. 02014 ◽  
Author(s):  
Semawi Nur Hikmah ◽  
Sulaiman Siti Zubaidah ◽  
Ahmad Mutamim Noor Sabrina ◽  
Abdul Mudalip Siti Kholijah ◽  
Che Man Rohaida ◽  
...  
Keyword(s):  
Particle Size ◽  
Pressure Change ◽  
Dust Explosion ◽  
Particle Sizes ◽  
Drying Process ◽  
Chain Reaction ◽  
Explosion Pressure ◽  
Initial Shock ◽  
Preliminary Study ◽  
A Chain

Food-based dust is considered as combustible dust as they composed of distinct particles, regardless of the size or chemical composition and when suspended in air or any other oxidizing medium over a range of concentrations will present a fire or deflagration hazard. The explosion effect from food-based dust can cause catastrophic consequences because the initial shock wave from the explosion lift up more dust and triggers a chain reaction through the plant. One of the parameters that can enhance the explosion is the particle size of the dust. In this study, the effect of four different particle sizes of tea dust on the dust explosion severity was tested in a confined 20 L explosion bomb. Tea dust tends to explode due to its molecular structure which contains a carbon-hydrogen bond that can release the significant amount of thermal energy. The experimental results showed that the values of Pmax and (dP/dt)max of tea dust were more severe for the particle size of 160 ?m for which are 1.97 bar and 4.97 bar/s before drying and 2.09 bar and 7.01 bar/s after drying process. The finer dust reacted more violently than coarser ones. As particle size decreases, the rate of explosion pressure change increases, as long as the size is capable of supporting combustion.

scholarly journals Comparative study of the explosion pressure characteristics of micro- and nano-sized coal dust and methane–coal dust mixtures in a pipe

2020 ◽  
Vol 7 (1) ◽  
pp. 68-78 ◽  
Author(s):  
Bo Tan ◽  
Huilin Liu ◽  
Bin Xu ◽  
Tian Wang
Keyword(s):  
Coal Dust ◽  
Pressure Rise ◽  
Dust Explosion ◽  
Nano Particle ◽  
Explosion Pressure ◽  
Deflagration Index ◽  
Pressure Maximum ◽  
Explosion Accidents ◽  
The Impact ◽  
Pressure Characteristics

AbstractCoal dust explosion accidents often cause substantial property damage and casualties and frequently involve nano-sized coal dust. In order to study the impact of nano-sized coal on coal dust and methane–coal dust explosions, a pipe test apparatus was used to analyze the explosion pressure characteristics of five types of micro-nano particle dusts (800 nm, 1200 nm, 45 μm, 60 μm, and 75 μm) at five concentrations (100 g/m3, 250 g/m3, 500 g/m3, 750 g/m3, and 1000 g/m3). The explosion pressure characteristics were closely related to the coal dust particle size and concentration. The maximum explosion pressure, maximum rate of pressure rise, and deflagration index for nano-sized coal dust were larger than for its micro-sized counterpart, indicating that a nano-sized coal dust explosion is more dangerous. The highest deflagration index Kst for coal dust was 13.97 MPa/(m·s), indicating weak explosibility. When 7% methane was added to the air, the maximum deflagration index Kst for methane–coal dust was 42.62  MPa/(m·s), indicating very strong explosibility. This indicates that adding methane to the coal dust mixture substantially increased the hazard grade.

Research on Open and Close Characteristics of Passive Shuttle-Type Anti-Water-Attack Check Valve

2011 ◽  
Vol 474-476 ◽  
pp. 2290-2295
Author(s):  
Bei Ping Xiang ◽  
Guo Fu Yin ◽  
Xiang Wei Zeng ◽  
Hong Bin Zang
Keyword(s):  
Flow Field ◽  
Rapid Change ◽  
Check Valve ◽  
Pressure Change ◽  
Pipeline System ◽  
Hydraulic Damper ◽  
Pressure Pipeline ◽  
Set Up ◽  
Opening And Closing ◽  
Type Check

Water-attack is very harmful to pressure pipeline system security. Passive shuttle-type anti-water-attack check valve can adjust its open and close time by hydraulic damper, and cushion the rapid change of liquid momentum in order to protect the pumps and pipelines. The structure and working principle of this passive check valve are introduced, and the dynamics model is set up. The opening and closing characteristics of the model is analyzed, and simulation comparison is done between the flow field and pressure change laws of shuttle-type check valve and those of swing check valve. The simulation result shows that the hydraulic damper works very well, the flow field of passive shuttle-type check valve is symmetrical, the forces acting on the shuttle is balanceable, and shuttle-type check valves can replace swing check valves in many fields.

Evaluation of Blast Loads From Pipe Ruptures

2017 ◽  
Author(s):  
Jihui Geng ◽  
Kelly Thomas
Keyword(s):  
High Pressure ◽  
Pressure Vessel ◽  
Explosion Hazard ◽  
Blast Loads ◽  
Gas Temperature ◽  
Spherical Vessel ◽  
Industrial Facilities ◽  
Pressure Pipeline ◽  
High Pressure Pipeline ◽  
Gas Volume

High-pressure pipeline ruptures are a credible explosion hazard at many industrial facilities. The blast field generated by a pipe rupture is highly directional. However, there have been few evaluations of the directional blast loads produced by pipe ruptures. This paper addresses the blast loads generated by a typical “fish mouth” type pipe rupture. The effects of five key parameters on the resulting directional blast field were examined: rupture opening speed, final rupture opening area, pipe diameter, initial gas pressure, and initial gas temperature. The resultant blast loads were compared to those based on existing blast curves for Pressure Vessel Bursts (PVB), the most common of which is based on an assumption of a spherical vessel geometry and instantaneous failure of the entire pressure vessel boundary. The effective gas volume (i.e., number of pipe diameters) required to achieve reasonable agreement between the blast load based on existing PVB blast curves and that resulting from a high-pressure pipeline fish mouth rupture for a specified direction was determined.

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 Explosion prevention and mitigation in plants which process, generate and store combustible dusts

2022 ◽  
Vol 354 ◽  
pp. 00041
Author(s):  
Adrian Marius Jurca ◽  
Mihaela Părăian ◽  
Niculina Vătavu
Keyword(s):  
Pressure Rise ◽  
Process Equipment ◽  
Process Industries ◽  
Explosion Pressure ◽  
Dust Clouds ◽  
Large Numbers ◽  
Burning Rates ◽  
Explosion Protection ◽  
Pressure Maximum ◽  
Protective Systems

Combustible dusts which are present in workplaces are a significant hazard which cannot be ignored by the plant owners, managers and workers. Combustible dust deflagrations and explosions have caused large numbers of deaths and catastrophic property damages in various industries, ranging from pharmaceutical plants to sugar factories. One may say that dust explosions in process industries always start inside process equipment such as mills, dryers, filters. Such events may occur in any process in which a combustible dust is handled, produced or stored, and can be triggered by any energy source, including static electricity, friction and hot surfaces. For any combustible dust type, several important parameters have to be taken into account when designing and using protective systems: i.e. the ease with which dust clouds ignite and their burning rates, maximum explosion pressure, maximum rate of explosion pressure rise. These parameters vary considerably depending on the dust type, their knowledge being a first step for carrying out a proper explosion risk assessment in installations which circulate combustible dusts. The paper presents the main aspects concerning explosion protection which have to be taken into account when designing protective systems intended to be used in explosive atmospheres generated by combustible dusts and the importance of selecting the proper explosion protection technique.

scholarly journals Determination of Explosion Characteristics of Sugar Dust Clouds

2018 ◽  
Vol 13 (1) ◽  
pp. 15-20
Author(s):  
Richard Kuracina ◽  
Zuzana Szabová ◽  
Matej Menčík
Keyword(s):  
Maximum Rate ◽  
Dust Cloud ◽  
Pressure Rise ◽  
Dust Explosion ◽  
Explosion Pressure ◽  
Maximum Explosion Pressure ◽  
Dust Clouds ◽  
Maximum Value ◽  
Explosion Limit

Abstract A dust explosion occurs when an airborne combustible dust cloud encounters an effective ignition source. The resulting pressure and temperature increase can severely injure people and damage surrounding equipment and buildings, and therefore needs to be prevented or controlled (Taveau, 2016). The article deals with the measurement of maximum explosion pressure and maximum rate of explosion pressure rise of sugar dust cloud. 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 Determination of explosion characteristics of dust clouds. Part 3: Determination of the lower explosion limit LEL of dust clouds. The sugar dust cloud in the chamber is achieved mechanically. The testing of explosions of sugar dust clouds showed that the maximum value of the pressure was reached at concentrations of 1000 g/m3 and its value is 6,89 bars.

A risk assessment methodology of aluminum dust explosion for polishing process based on laboratory tests

2021 ◽  
pp. 1748006X2098737
Author(s):  
Haipu Bi ◽  
Xiaolong Xie ◽  
Kaimin Wang ◽  
Yujie Cao ◽  
Hui Shao
Keyword(s):  
Risk Assessment ◽  
Particle Diameter ◽  
Scientific Basis ◽  
Dust Explosion ◽  
Dihydrogen Phosphate ◽  
Assessment Methodology ◽  
Polishing Process ◽  
Explosion Pressure ◽  
Risk Assessment Methodology ◽  
Explosion Risk

The secondary dust explosion ignited by the primary explosion energy often causes greater damage to the just destroyed carrier. Therefore, the study of explosion risk as well as the risk reduction effect with suppression is key guard against the secondary and derivative explosions. A novel risk assessment methodology is presented based on Monte Carlo theory for numerically fitting pressure’s uncertainty changes and Crystal ball simulation for calculating explosion risk and its distribution probability of hazardous explosive dust. Taking the aluminum dust of a polishing process as an example, the fitted results show that the tested explosion pressure in laboratory presents the shape of lognormal distribution with average pressure of 0.27 MPa on the condition of 500 g/m3 aluminum dust with median particle diameter at 35 μm. The simulated results show that the risk possibility of myringorupture injury, pneumorrhagia injury, and structure damage all approaches 100% because of the high explosion pressure considering the potential percentage of injury or damage at 50%. However, the risk possibility reduces to 14.27%, 0.13%, and 42.05% with suppressants of ammonium dihydrogen phosphate at 10%, respectively. The proposed method of risk assessment for dust explosion and its suppression provides scientific basis for strategy optimization of dust explosion protection and safe production of fine explosive dust related industry.

scholarly journals Internal explosion. Pressure peaks

2021 ◽  
Vol 263 ◽  
pp. 02041
Author(s):  
Vyacheslav Gorev ◽  
Evgeniya Chelekova
Keyword(s):  
Numerical Modeling ◽  
Small Volume ◽  
Pressure Change ◽  
Explosion Pressure ◽  
Scale Modeling ◽  
Gas Explosions ◽  
Internal Explosion ◽  
Pressure Dynamics ◽  
The Moment ◽  
Protective Structures

Internal emergency gas explosions occur at threatening intervals and cause significant destruction. The level of destruction indicates the imperfection of protection methods. Documents regulating the use of safety structures for the protection of buildings during an internal explosion are limited by the assignment of the area of openings covered by safety structures, without taking into account the properties of these structures, attachment methods and the rate of pressure increase during an explosion. The purpose of the work is to take into account as much as possible the influence of the properties of the protective structures, their attachment and the nature of the explosion on the dynamics of the explosion pressure change. The second goal is to obtain a methodology for converting the results of experimental results obtained on small volumes to determine the parameters of an explosion in conditions of large volume. The goals are achieved by the theory of dimensions and similarity using numerical modeling. The work revealed dimensionless complexes describing pressure dynamics both during opening of openings and at the moment of maximum power of energy release during explosion. Possibility of experimental scale modeling of processes of opening of safety structures is shown. In particular, it is shown that during an explosion in premises of a small volume (residential), the pressure during opening is more often critical.

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