Explosion proof and anti-static bag filter

1、 Product Introduction:
Explosion proof and anti-static bag filter dust collection hood is a device for controlling dusty airflow and collecting dust. It is an important component of the bag filter dust collection system. The function of the explosion-proof and anti-static bag filter dust collection hood is to capture the dust emitted from the dust source and introduce it into the purification system to prevent it from spreading to the production workshop and the atmosphere, causing pollution. If the form and location are chosen reasonably, the dust collector can achieve good dust removal effect by using a smaller exhaust volume.
The explosion-proof and anti-static bag filter is a professional dust collection equipment developed based on the ordinary pulse bag filter, combined with the fine particle size, flammability, and explosiveness of coal powder dust from coal mills. It has been widely used in China. The coal mill type pulse bag filter adopts anti-static filter material, and the body has an explosion-proof structure and a pressure relief device, which has explosion-proof performance and is suitable for coal powder preparation systems and the collection of flammable and explosive dust. This device has fewer mechanical components, requires less maintenance work, and is easy to change bags. The explosion-proof pulse dust collector for coal mills is widely used for dust collection in industries such as cement, power, metallurgy, and chemical due to its use of pulsating chamber cleaning, which has high dust collection efficiency and can operate efficiently for a long time. The dust collection efficiency is above 99.8%.
2、 Classification of explosion-proof and anti-static bag filters:
The explosion-proof and anti-static bag filter dust collection hood of Henan Environmental Protection Equipment Factory can be divided into various forms due to different production process conditions and operating methods. According to the airflow flow mode of the hood, it can be divided into suction type and blow suction type. According to the structure of the gas collection hood, it is mainly divided into four categories: closed hood, semi closed hood, external hood, and blowing and suction hood. This classification method is commonly used.
(1) Explosion proof and anti-static bag filter sealed cover
Explosion proof and anti-static bag filter sealing cover is used to completely seal the dust source or the entire process equipment, limiting gas diffusion in a small enclosed space. It only requires a small exhaust volume to effectively prevent dust or other harmful substances from entering the room, while also reducing air volume and investment. Therefore, when designing a local exhaust system for a dust removal system, this device should be considered first.
Explosion proof and anti-static bag filter sealing covers can be divided into partial sealing covers, integral sealing covers, and large capacity sealing covers according to their sealing degree. For example, the dust outlet of the crusher, the transfer point of the belt conveyor, the vibrating screen, the sandblasting room, etc. are all suitable for using sealed covers for dust collection.
(2) Explosion proof and anti-static bag filter semi closed cover
The semi closed cover of the explosion-proof and anti-static bag filter has large holes for convenient process operation. It controls the escape of harmful substances through the intake airflow at the orifice. Due to the increased intake of air outside the hood, the exhaust volume of this hood is larger than that of a sealed hood. But smaller than other forms of gas collection hoods. Semi closed covers can be divided into box covers and cabinet covers according to their appearance.
3、 The structural principle of explosion-proof and anti-static bag filter:
Combustion reactions require combustible materials and oxygen, as well as a certain amount of ignition source energy. For dust explosions, three elements should be present: ignition source; Combustible fine dust; Dust is suspended in the air, forming a dust cloud within the explosive concentration range. Only when these three elements coexist can an explosion occur. Therefore, as long as one of the conditions is eliminated, the occurrence of an explosion can be prevented. The following technical measures are commonly used in bag filters.
(1) In the special design of the explosion-proof structure, in order to prevent the accumulation of combustible dust in the internal components of the dust collector, all beams, partition plates, etc. should be equipped with dust-proof plates, and the slope of the dust-proof plate should be less than 70 degrees. The slip angle of the ash hopper is greater than 70 degrees. In order to prevent dust accumulation due to the small angle between the two hopper walls, two adjacent side plates should be welded with slip plates to eliminate dust deposition. Considering the occurrence of ash hopper condensation and blockage due to abnormal operation and high dust humidity, steam pipe insulation or tubular electric heaters should be added to the high-temperature dust collector on the ash hopper wall plate during the design of the ash hopper. To prevent material accumulation in the ash hopper, each ash hopper also needs to be equipped with a bin arm vibrator or air cannon.
One dust collector can have as few as 2-3 ash hoppers and as many as 5-8 hoppers. During use, it may cause deviation due to uneven air flow, resulting in uneven coal powder content in each hopper and a large amount of ash behind H. To solve the problem of uneven air flow, the following measures can be taken in the structure:
① Add a wind deflector on the inclined partition of the air duct, as shown in Figure 5-168. The size of the baffle should be determined based on the principles of equal air volume and equal air pressure; ② Considering the changes in the actual situation on site, adjustable adjustment is adopted between the lifting valve stem and the valve plate to make the outlet height h a variable value for further correction; ③ Install an air volume regulating valve in the inlet branch pipe to adjust the air volume of each compartment after the equipment is in operation. Control the difference in air volume between each compartment within 5%.
(2) The use of anti-static filter bags inside the dust collector can generate static electricity due to the friction between high concentration dust and the filter cloth during the flow process. The accumulation of static electricity can generate sparks and cause combustion. For the pulse cleaning method, polyester needle punched felt is used for the filter bag. To eliminate the insufficient static electricity caused by polyester needle punched felt, conductive metal wires or carbon fibers are spun into the filter bag fabric. When installing the filter bag, it is connected to the workshop grounding grid through a steel frame and porous plate, and then connected to the workshop grounding grid through the shell. Various anti-static products such as MP922 have been developed for filter bags used in anti blowing dust cleaning. The usage effect is very good.
(3) Setting up safety holes (valves) is essential to limit the explosion within the bag filter and prevent it from expanding to other areas. It is important to install safety holes and essential fire suppression equipment. The purpose of setting up safety holes is not to prevent explosions, but to limit the explosion range and reduce the number of explosions. Most dust collectors that handle explosive dust operate under safety hole conditions. Because of this, the design of safety holes should ensure that they can effectively function in the event of an explosion accident; Strengthen the maintenance and management of safety holes in daily life.