What is the meaning of the filter bag aid?

Bag house filter aid for precoat selection principle is a wide source of cheap, pollutants have good adsorption and absorption. In general, large specific surface area, applied after the bag does not result in excessive increase in filtration resistance, and can absorb, or absorb the gas, the fine powder suitable for liquid pollutants aid. Select the appropriate filter aid is to improve the pre-coat bag filter trapping effect of the key. Such as coking plant for purifying smoke containing tar and pitch coke powder coking process uses adsorption obtain the ideal result, oil smoke removal efficiency of 95%. The main features of the pre-coat effect is due to the baghouse filter aid, pre-coated bag filter can purify traditional baghouse can not be purified contain tar component, oil component, sulfide, and fluoride below the dew point of the gas dust together, fixing for strong adhesion of dust is relatively easy to handle. Although the pre-coat and bag filter aid has been recognized as effective in capturing some of the gas and liquid pollutants, but they are specific to the experience and the specific contaminants in the process gained on pre form coat bag filter, filter aid selection and addition method is still the application process development and research. 3, bag filter pre-coat application (1) purified sulfide sulfur in the coal combustion is the main form of sulfur dioxide in the presence of such gaseous sulfur dioxide is not directly collect and capture any kind of filter. Through the flue gas containing sulfur dioxide and dust injecting slaked lime powder and reaction assistants to achieve desulfurization. Slaked lime and sulfur dioxide in the reaction aid aid Full chemical reaction to form solid calcium sulfate, or attached to the dust condensed into fine particles together with dust is collected down baghouse. Put the amount of lime powder and additives depends on how much sulfur dioxide in the flue gas may be, the process has a sulfur content of automatic measuring device to ensure that the amount of dry powder and additives economy. Slaked lime powder and reaction assistants are stored in their respective storage tanks, the amount invested by the automatic adjustment device control. (2) production of aluminum fluoride purification process emits large amounts of fluorine gas, aluminum electrolytic plant raw material alumina powder as a filter aid, added to the reactor before the baghouse, the alumina powder aluminum adsorption electrolyzer to produce fluorine-containing gaseous and solid fluoride, then filtered through a bag filter dust. Alumina as the adsorbent need a certain solid-gas ratio (per unit volume of flue gas volume of solid adsorbent amount, g / m3) was added to the reactor, the flue gas with alumina strongly turbulent mixing, flue gas wherein the alumina with hydrogen fluoride to produce a compound surface adsorption surface reaction of aluminum fluoride. This reaction proceeds very quickly, in a matter of seconds to complete. Bag filter flue gas after reaction separated contained fluorine alumina, it can be directly used in the electrolytic production of fluoride salt and can replace part of the raw material. The whole process is almost a closed loop process. Baghouse operation and maintenance management to ensure the stable operation of the precipitator, to achieve the desired effect of dust is important.