Bag dust collector application technology

With the development of bag dust removal technology and the increasing environmental protection requirements, bag filter has become more and more widely used. At present, bag filter can be used to treat high temperature, high humidity, bonding, explosion and abrasive smoke. Even filtering air containing ultra-fine dust.
1. High-temperature, high-humidity gases The flue gases of various industrial furnaces, dryers, etc. are all high-temperature flue gases, most of which also contain large amounts of water and sulfur oxide gases. The bag filter can currently process flue gas at temperatures below 300 °C. Exceeding this temperature, the flue gas should be pre-cooled. In special cases, high-temperature flue gas of 450-550 °C can be directly treated with metal fiber filter. The use of bag filter to treat flue gas from high-temperature kiln such as steam boiler, cement kiln, metallurgical furnace, incinerator, etc. is becoming more and more popular at home and abroad. Although the bag filter is limited by the temperature resistance of the filter material, it can handle high temperature flue gas with a temperature of up to 1200-1400 °C by properly treating the system flue gas.
2. Adhesive dust The cohesive dust is easy to be squashed on the surface of the filter bag. The bag filter can treat the cohesive dust by adsorption. That is, the appropriate amount of porous powder is mixed into the system pipe, and the powder is used. The cohesive dust is adsorbed and then purified by a bag filter. For example, the refractory plant uses dolomite powder to adsorb and purify bituminous flue gas. The aluminum plant uses alumina to adsorb bitumen and hydrogen oxide. The road company's asphalt concrete workshop uses limestone powder to adsorb bituminous smoke, and its adsorption efficiency can reach 92-99%.
3. Explosive dust Explosive dust must explode only when it has the following three conditions: (1) flammable substances are present in the flue gas at appropriate concentrations; (2) have sufficient oxygen and oxidants; (3) have a source of ignition. Therefore, measures to destroy these three conditions or certain conditions should be taken when purifying such gases. Simply put, it is to control the ingredients, eliminate the fire extinguishing species; eliminate static electricity, equipment grounding; monitor explosion-proof, fire extinguishing and explosion.
4. Corrosive gases In the flue gas purification system, there are mainly two kinds of gases, such as gas and dust, which are corrosive to the bag filter, such as sulfuric acid gas formed by the presence of sulfur molecules in coal or heavy oil fuel, or water Will produce a variety of salt dust. Since the corrosion phenomenon in the flue gas purification occurs when the flue gas temperature appears below the acid dew point, it is necessary to ensure that the system flue gas operates above the dew point temperature. In the selection of filter materials, the characteristics of corrosive substances should be generated according to the flue gas, and the corresponding filter materials should be used. For the corrosion system with serious corrosion and high requirements, such as pharmaceutical, food, carbon black production and other industries, the importance of bag filter is important. Parts should be made of stainless steel or painted with an anti-corrosive coating.
5. When the abrasive dust is used to treat abrasive dust such as alumina, silica, sinter, etc., the coarse particles in the dust and the airflow in the bag filter are too high, resulting in the filter bag and the casing of the dust collector. Strong wear, for this reason, generally take measures to reduce the absolute amount of coarse dust in the flue gas and reduce the flow rate of the dust-containing gas, such as pre-dusting device before the flue gas enters the bag filter, Strictly control the inlet flow rate of the filter bag, the air inlet is easy to grind and wear resistant materials.