Ignition sources and scientific treatment methods in bag dust collectors

The ignition sources in the bag dust collector are mainly the following: ordinary ignition sources, cremation caused by impact or friction, electrostatic cremation and shell temperature, etc.

1. Common ignition sources

It is mainly brought in directly by external fire sources, especially gas cutting flames and welding sparks. Since bag dust collectors are generally welded parts, gas cutting flames and welding sparks are mainly generated when repairing instruments. Therefore, they can be controlled by strengthening management and improving workers' awareness of explosion prevention. When repairing instruments, dust around the repair parts must also be removed.

2. Sparks generated by impact or friction

Sparks are usually caused by the collision of metal objects such as nuts or iron blocks being sucked into the baghouse dust collector. The main elimination methods are: setting up an appropriate metal mesh and electromagnetic iron removal device at the dust collection hood to prevent metal from entering the dust collection pipe and baghouse dust collector. After maintenance, metal materials falling into the pipe should be removed in time. Secondly, the ventilator is arranged on the clean air side behind the bag dust collector to prevent metal foreign objects from colliding with the high-speed rotating blades of the fan to generate sparks, and to prevent flammable and explosive dust from friction, heat and combustion with the high-speed rotating blades. The wind speed in the pipe network must be reasonable. Excessive wind speed can cause dust to accelerate wear on the pipes.

3. The mechanism of static electricity generation is not yet clear, but measures can be taken to prevent static electricity.

Select substances that are similar to the charged sequence, or combine them with substances that are opposite to the charged sequence to minimize the contact potential difference, so that the generation of static electricity can be suppressed. The positive and negative charges they carry neutralize themselves to achieve the purpose of eliminating static electricity. Secondly, grounding is one of the common leakage measures. Equipment, containers, pipes, etc. should be maintained at equal potential. Depending on the actual situation, use a decentralized or centralized grounding system for reliable grounding, and the grounding resistance is required to be within the range of 1-4Ω. In addition, to increase conductivity, use conductors or conductive substances instead of highly insulating substances. In addition, the dust layer accumulated on the filter bag increases the intensity of the spatial electric field, which may break down the air and cause spark discharge. You can also use methods to increase the ambient humidity to leak static electricity, or you can directly add water during the production process.

3. Keep the temperature of the dust collector shell not too high. Because a large amount of dust is adsorbed by the inner wall of the shell, the surface of the dust is heated when the temperature of the shell is too high. After obtaining energy, it melts and vaporizes and bursts out hot tiny proton particles or sparks, which also form an ignition source for the dust. Therefore, control the ambient temperature and do not place the bag dust collector outside the house.