Looking back at Taiwan 6.27 dust explosion enterprises how to prevent?

Around June 27, 2015 8:40 evening, Taiwan's new amusement park north of the Eight Immortals Dust explosion injured a total of 498 people were injured, 12 people were killed.

At the time, Taiwan’s New North Eight Immortals Amusement Park was hosting a “color party”. This is a crazy party based on India’s “Color Festival”. The core link is to play with each other by throwing coloring powder. The organizers claimed that it was a "Asia's largest party of color," "dare to play, dare to music, the most swing," a "historic party" activities. As many as a few thousand young people were inspired by this, they happily rushed to the Eight Immortals Park to receive the “baptism” of color powder. In front of the "Color Party" stage, there was a sudden fire. Many people did not know that it was an explosion at the beginning. Many people continued to dance until the screams began to scream in front of the stage before they knew of an accident.

First, the casualty report schedule:

June 27 evening, the injured were sent to freshwater Mackay 15 people, Taipei Mackay 4, Taipei Veterans General Hospital eight people, 14 people Shin Kong Hospital, Chang Gung Memorial Hospital, Taoyuan 31 people.

June 28, Taiwan's "Central News Agency" message, Taiwan, New Taipei City Bureau of Health Statistics found that 28 late referral process, duplicate data, remove duplicate number of injured, the number of the wounded from under 524 repair 498 people, 43 were sent to hospital . According to statistics, according to the hospital's ambulance detection, 79 were minor injuries , 157 were injured, and 202 were seriously injured . [3]

July 5, Taiwan's "Ministry of Health, Welfare" announcement, there are still 434 people in 13 counties and cities in Taiwan, 48 hospitals for treatment, 282 people in the intensive care unit, was notified to dying is increased to 237 people, has been Caused 2 deaths.

On July 23 , 343 people in the dust explosion in the Eight Immortals of New Taipei City continued to be hospitalized in 42 hospitals. Among them, 213 were in intensive care units and 162 were critically ill, of whom 6 were dialysis and 56 were intubated , causing 9 People lost their lives.

On September 2 , the number of victims of dust explosions in the Eight Immortals of New Taipei City rose to 12 .

Second, the cause of the incident:

After several experiments, Taiwan, New Taipei City Fire Department August 27, 2015 to make a formal appraisal report, the culprit was found on fire right in front of the stage BEAM200 fixtures. The cause of the fire was that part of the corn flour was spilled on the lamp surface. Hundreds of degrees of high temperature caused an explosion. The fire spread through the corn powder on the ground and caused a tragedy.

The report pointed out that the concentration of dust in the air before the explosion has reached the lower explosion limit, more than 45 grams per cubic meter . Due to the crowd's jumps, wind blows, and the staff’s continuous spraying of corn powder with carbon dioxide cylinders, the 430- degree corn flour was exposed to a scanner with a surface temperature of over 400 degrees, causing fire, but it was only due to the ignited air. It will give people the illusion of "explosion."

This report has already been submitted to the Public Prosecutors Office of the Shilin District Court in Taipei. The prosecutor has not formally responded to the report. The prosecutor will use this report as the basis for the investigation, but since the investigation is not yet completed, the prosecution cannot disclose more details about the incident.

Third, dust explosion:

This time, the Color Party (Rainbow) of New Taipei has no dangerous awareness. Without any precautionary measures and supervision over dust explosions, a group of young people pursuing fashionable stimuli use corn flour to play "Rainbow", but there is no sense of danger. This is an important cause of massive burns.

"The explosion is actually uncontrollable combustion," so analysis explosions are mainly analyzed from the "burning tetrahedron":

Combustibles: corn flour, Class III A explosives. Dust must be suspended in air and mixed with air to reach a certain concentration range to form combustible / explosive mixed “stratus clouds”. Dust of diffusion typically less than 10 μ m in diameter was greater than gravity.

Combustion: Oxygen, usually air. Here, we must say that the smaller the particles, the larger the specific surface area and the stronger the oxygen adsorption ability. After an explosion, a local negative pressure was formed in a very short period of time, fresh air was transmitted to the explosion point, and the deposition dust was raised. The concentration was greater than the first time, and the destructive power of the explosion was even more serious.

Ignition energy: open flame, high temperature, static electricity or other energy. According to news reports, it was initially suspected that this was an explosion caused by a cigarette butt. The minimum ignition energy of a dust explosion is generally several tens of mJ to several hundred mJ , which is equivalent to about one hundred times that of gas ignition energy. The surface temperature of cigarette butts is between 200 °C and 300 °C , and the center temperature is as high as 700 °C and 800 °C . The ignition point of the general flammable substances is below this.

Chain reaction: Chain reaction theory believes that some intermediate products (also called “radicals”) may be produced during the reaction (such as fire or explosion). The chemical reaction at this time depends not only on the reactants but also on the intermediate products. . Usually, the chain reaction includes "chain initiation, chain transmission, and chain termination." The first explosion produces higher temperature and energy. At the same time, because the local negative pressure will form a higher explosion mixture, new free radicals are more likely to be generated, and the secondary explosion is more likely to occur. More likely to appear. With the continuous explosion, the reaction speed and explosion pressure continue to increase and increase, and show jumping development. When obstacles or roadway bends are encountered in explosion propagation routes, the pressure rises sharply, so the farther away from the explosion point, Destructiveness may be more severe.

Scientifically preventing dust explosions in the safe production process of enterprises should also take corresponding measures from the above four aspects:

Eliminate or strictly control dust sources: first, eliminate dust generation; second, avoid the appearance of dust mixtures; enterprises should purchase qualified dust removal devices, increase environmental humidity, and artificial dust removal;

The air is ubiquitous, and it is very difficult to control the combustibles. We can only think of ways to make the dust mixture concentration not be between the lower explosive limit ( LEL ) and the upper limit ( UEL ), such as the mechanical ventilation in the working environment;

Strictly control the ignition source: mainly control the open fire (lighter, movement, cigarette butts, welding, etc.), prevent energy accumulation (dust is easy to accumulate heat in the wet environment), prevent high temperature environment, and make static electricity grounding.

The elimination of old free radicals and the generation of new free radicals in chain reactions are also factors that are difficult for humans to control. The principle of fire extinguishment of halogenated alkanes is in fact cutting off the transfer of free radicals.

Others: It is the measures to reduce the destructiveness when an explosion occurs, such as the use of lightweight materials, vent walls, etc. on the roof of an operating building.

Fourth, preventive measures

1. Firstly, we must install qualified dust treatment equipment and carry out regular inspections and inspections of important departments.

2. The connected fan ducts are regularly cleaned to keep the ducts open.

3. On-site maintenance of operating environment

4. Equipment installation explosive device,

5. Electrical equipment with explosion-proof electrical, reliable grounding, and regular lightning protection tests.

6. Establish a hidden trouble investigation management system, conduct on-site personnel safety training, and hold certificates.

7. Fireworks are prohibited on the scene. This red line is unbreakable.

The information in this article comes from the Internet and was reorganized and edited by China Rescue Equipment Network.