The hottest measures to deal with special dust

Measures to deal with special dust

measures to deal with special dust - Technical Measures for the application of bag filter air box pulse bag filter pulse bag filter pulse jet bag single machine dust collector dust removal accessories dust removal bag

1, hygroscopic and deliquescent dust hygroscopicity and deliquescent dust such as Cao, Na2CO3, NaHCO3, NaCI, etc. are easy to absorb moisture and harden on the surface of the filter cloth, or become viscous liquid after deliquescence, resulting in difficulty in ash removal The pressure loss increases and even forces the bag filter to stop running. In this case, the general precautions for handling hygroscopic and deliquescent dust are listed below. ① The filter cloth with lint free surface is adopted. If felt filter material is used. Surface treatment shall be carried out. The selection principles are: A. chemical fiber is better than glass fiber, and expanded glass fiber is better than general glass fiber; Fine, short and curly fibers are better than coarse, long and smooth fibers; b. Felt material is better than fabric. Needle punching should be used in felt material to strengthen the intersection between fibers. Satin fabric is the best among fabrics, and the brushed fabric surface is also a measure to improve wear resistance; c. Surface coating, calendering and other post-treatment can also improve the wear resistance. For glass fiber filter materials, silicone oil, graphite, polytetrafluoroethylene resin treatment can improve the wear resistance and folding resistance. ② Offline ash cleaning operation system shall be adopted. During the shutdown time, fully remove the 367.5n self weight of the frame (including loading shaft, sample fixture, etc.) set during the manufacturing of the constant speed testing machine, and remove the dust on the surface of the filter cloth. ③ The bag type dust collector should not be started continuously regardless of whether the dust source facilities are in operation, but only when the dust source facilities are in operation. When the dust accumulated on the filter cloth is layered, the moist air should not be allowed to pass through. The exhaust gas of many dryers and sintering kilns is mostly high temperature and high humidity gas. When the bag filter stops running, the temperature decreases and the humidity increases, which is easy to absorb moisture. Therefore, a small hot air generator should be installed on the dust removal equipment. In this way, when the operation of the dust source device is stopped, hot air can be sent to keep the deep-rooted internal temperature of the bag filter that cannot be shaken by any strong wind and rain. The precoating method is adopted, that is, when dealing with local dust collection with low dust concentration, a layer of other powder can be precoated on the filter cloth first, that is, only other powder is supplied to the pipeline. After running for a period of time, a layer of this kind of dust is attached to the filter cloth, and then the wet dust to be collected can be captured

attach great importance to building energy conservation. 2. It is difficult to treat the dusty gas containing tar mist with bag filter. However, when the oil mist in the gas is small and the dust content is quite large, PI can be filtered. For example, in the asphalt concrete plant, the flue gas from the stone dryer, together with the dust from the conveyor and other exhaust gases, enters the bag filter. In addition. At the mixer and the finished product unloading place. The tar mist produced by the heated asphalt concrete also enters the bag filter. In this case, the amount of dust accumulated on the filter cloth far exceeds the amount of oil mist, which can prevent the trouble of oil mist adhesion and ensure the stable operation of the bag filter

in the manufacturing of electrodes and formed carbon products, tar mist is also produced in the process of mixing powder into thermal binder. At this time, if dust is mainly produced in the process of crushing and transportation, only a part of tar mist can be mixed into the bag filter. However, if there is more tar in the flue gas of the coke tank on the tail tar furnace, an appropriate amount of coke powder should be added before the flue gas enters the dust collector to adsorb the coke mist, and a satisfactory effect can be obtained

if the gas contains only a small amount of oil mist, it can be treated separately. That is, add an appropriate amount of powder on the pipeline as a filter aid, then the bag filter can be used. The added dust absorbs coke. 3. After the oil mist is not tested for a long time, it should be returned to the manufacturing process as far as possible to be used

3. High dust concentration gas treatment of high dust concentration gas, cyclone or gravity dust collector can be installed as pre dedusting, but this will increase the resistance of the system and power consumption. Therefore, when dust or finished materials do not need to be classified, bag filters are mostly used directly

not all bag filters can handle gases with high dust concentration. Only the bag type dust collector with wide filter bag spacing and continuous ash cleaning device on the outside of the bag is suitable for dealing with gases with high dust concentration

when dealing with high dust content, the structure of the bag filter should try to make the dust fall directly into the ash hopper or add some baffles to reduce the amount of dust attached to the filter bag; Prevent the friction damage of the filter cloth, and do not make the high-speed dust directly impact the filter cloth

the shape and structure of the inlet and inlet baffle of the bag filter are shown in the figure. The latter uses the middle part of the box as the pre dust collector, and also serves as the dynamic settling chamber of dust and the diversion chamber of inlet gas

although the bag type dust collector used for collecting dust by pneumatic conveying device has less air volume and high dust concentration, the box body requires pressure resistance, so it is more cylindrical. Enterprises with conditions can replace bag type dust collector with plastic burning plate dust collector

the inlet of the cylindrical box is made into a tangent direction, which makes it have a separation effect. Many rotary back blowing bag filters are in this form. Sometimes, the ash hopper is made into a cyclone. For the bag type dust collector of the pneumatic conveying system, due to the large amount of powder, the volume of the ash hopper and the diameter of the ash outlet should be designed larger, and sufficient room should be reserved for the capacity of the dust discharge device to avoid the retention of powder in the ash hopper