The dust collector is mainly composed of an upper box, a middle box, an ash hopper, an air inlet equalizing pipe, a supporting filter bag, a blowing device and an ash discharging device. Dust-containing gas enters the ash hopper of each room from the air inlet equalizing pipe of the dust collector. Under the shunt of the ash hopper shunt device, large particles of dust are separated and directly fall into the ash hopper, while finer dust evenly enters the middle box and is adsorbed on the outer surface of the filter bag. Clean gas enters the upper box through the filter bag and is discharged into the atmosphere through various off-line valves and exhaust pipes. With the progress of filtration, the dust on the filter bag accumulates more and more. When the equipment resistance reaches the limit resistance value (generally set to 1500Pa), the dust removal control device will automatically close the one-room off-line valve according to the set value of pressure difference or the set value of dust removal time, and then open the electric pulse valve to stop blowing according to the set procedure, so that the pressure in the filter bag will increase by using compressed air for instant blowing. So as to shake off the dust on the filter bag (even if the fine dust is stuck). The working principle of the cyclone dust collector with the bypass is that the dust-containing gas enters tangentially from the inlet, while the airflow gets rotary motion, and the airflow is separated up and down to form the motion of the double spiral volute. The dust has a strong separation effect at the boundary of the double spiral volute, and the coarse dust particles are separated to the outer wall with the downward spiral volute airflow, some of which are led out from the hole in the middle of the bypass separation chamber, and the rest are brought to the ash hopper by the downward airflow. The upward spiral vortex airflow can gather fine dust, thus improving the dust removal efficiency. This part of fine dust particles is carried upward by the rising spiral vortex airflow, forming a strongly rotating upper dust ring under the top cover, entering the upper hole of the bypass separation chamber together with the rising spiral vortex airflow, and being introduced into the cone through the air return port to join with the internal airflow. The purified gas is discharged from the exhaust pipe, and the separated dust enters the hopper.
After the dust-containing gas enters the equipment from the air inlet at the top of the equipment, it passes through the cyclone separator at high speed, so that the dust-containing gas rotates downward along the axial adjusting screw, and the coarse particles of dust are removed by centrifugal force, effectively controlling the initial dust concentration entering the electric field. Then, the gas enters the electric field through the lower ash hopper to do work. Because the cross-sectional area of the lower ash hopper is several times larger than that of the inner pipe, according to the principle of constant rotating torque, the radial wind speed and axial wind speed drop sharply to produce a zero-speed interface, which makes the heavy particle dust in the inner pipe settle in the lower ash hopper, thus reducing the dust concentration entering the electric field. Low-concentration dust-containing gas condenses on the anode plate and cathode plate by electrostatic precipitation, and the collected dust is transported away by dust locking device through dust cleaning and vibration. In order to prevent the secondary dust from being generated in the lower ash hopper after the cyclone of the inner tube and the vibration of the electric field plate, an isolation cone is specially set in the lower ash hopper.
Scope of use: various mills in cement, fertilizer and other industries, feed inlets of crushing points, packaging machines and dryers, and various similar dispersed sources. Under the action of the main fan of the system, the dusty gas enters the gas box at the bottom of the dust collector from the air inlet at the lower part of the dust collector for pretreatment, and then enters each dust removal chamber of the upper box from the bottom; Dust is adsorbed on the outer surface of the filter cartridge, and the filtered clean gas enters the clean air cavity of the upper box through the filter cartridge and is collected and discharged at the air outlet.
With the continuous filtration conditions, the dust accumulated on the outer surface of the filter cartridge will accumulate more and more, which will increase the running resistance of the equipment accordingly. In order to ensure the normal operation of the system, the upper resistance limit of the dust collector should be maintained in the range of 1400 ~ 1600 Pa. When it exceeds this limited range, the PLC pulse automatic controller will issue instructions through constant resistance or timing to carry out three-state dust removal.
The cleaning process of the filter cartridge dust collector is to cut off the clean gas outlet channel of a room, so that the room is in a static state of airflow, then carry out compressed air pulse back blowing to clean the dust, and then open the clean gas outlet channel of the room after a few seconds of natural sedimentation, which not only thoroughly cleans the dust, but also avoids the secondary adsorption of the dust generated by blowing the dust, so that the dust can be recycled from one room to another. Because the explosive dust of aluminum powder is likely to explode or burn under a certain concentration of spark or static electricity.
Because aluminum powder explosion, the most critical factor is aluminum powder concentration, and the most effective way to control aluminum powder explosion is to control aluminum powder concentration. The dust collector is a tool to control the concentration of aluminum powder in the equipment. As long as the dust collector of the shot blasting machine is in good working condition and the dust removal effect is good, the aluminum powder concentration of the whole shot blasting machine equipment will not increase. Therefore, whether the equipment can operate normally is the key to ensure the good dust removal effect of the dust collector. The dust removal effect mainly depends on the filter material. When the filter material is blocked, the dust removal effect will be greatly reduced. When the filter material is well ventilated and filtered, the pressure difference between the static pressure chamber and the dynamic pressure chamber of the dust collector will be stable in a fixed range, so controlling the pressure difference of the dust collector is the most effective method to control the working state of the dust collector. Based on this, Disha Company invented the explosion-proof dust collector. The main method is to install the differential pressure controller near the dust collector of the shot blasting machine where there is no vibration. When the dust collector of the shot blasting machine is blocked for a period of time, the pressure difference detected by the instrument will change. When the detected value exceeds the set upper and lower limits, the differential pressure controller will control the cleaning mechanism of the filter bag of the vacuum cleaner to work, such as the vibration or back blowing mechanism, so as to remove the dust on the surface of the filter material of the vacuum cleaner, thus ensuring that the vacuum cleaner has a good working condition. When the automatic cleaning still can't meet the requirements, the differential pressure controller will control the alarm and control the equipment to stop automatically to prevent accidents.
In order to ensure the safe operation, we also installed the gravity automatic explosion-proof door at the key position of the shot blasting machine dust collector. This device is generally designed at the top of shot blasting room and dust removal pipeline, where the dust is dense. After accurate calculation, the device can automatically open the door when the explosion occurs, release the explosion pressure, and avoid damage to equipment and personnel. After the pressure is released, the door closes automatically under the action of gravity.
The shot blasting machine adopts FEF2 10 back-blowing bag filter, the dust removal efficiency is over 99%, and the waste gas emission is ≤90mg/m3, which meets the industrial "three wastes" emission standard GBJ4-73. The main fan power is 30kw. The dust removal bag is made of needled felt industrial filter cloth with antistatic function, which can be easily taken down for cleaning and reuse. Moreover, the filter bag is reliably grounded during installation, which can effectively avoid the possibility of aluminum powder explosion caused by static electricity.
Pulse bag filter
Pulse bag filter has been widely used and improved at home and abroad since it came out in 1950s, and great progress has been made in purifying dusty gas. Due to the adoption of advanced dust removal technology, the gas-to-cloth ratio is greatly improved, and it has the characteristics of large air handling capacity, small occupied area, high purification efficiency, reliable work, simple structure and small maintenance. The dust removal efficiency can reach above 99%. It is a mature and perfect high-efficiency dust removal equipment.
trait
1. The dust collector adopts separated air stop pulse injection technology, which overcomes the shortcomings of traditional pulse dust collector and separated back-blowing dust collector, and has the characteristics of strong dust cleaning ability, high dust removal efficiency, low emission concentration, low air leakage rate, low energy consumption, less steel consumption, less floor space, stable and reliable operation and good economic benefits. It is suitable for dust gas purification and material recovery in metallurgy, building materials, cement, machinery, chemical industry, electric power, light industry and other industries.
2. Because dust removal can be realized by pulse blowing and one-time blowing in different rooms, the dust removal cycle is prolonged, the dust removal energy consumption is reduced, and the compressed air consumption is greatly reduced. At the same time, the fatigue degree of filter bag and pulse valve is also reduced accordingly, thus doubling the service life of filter bag and valve plate.
3. Under the normal operating conditions of the system, bags can be replaced in different rooms without stopping the system fan. The mouth of the filter bag adopts elastic expansion ring, which has good sealing performance and is firm and reliable. The keel of the filter bag is polygonal, which reduces the friction between the filter bag and the keel, prolongs the life of the filter bag and is convenient for unloading.
4. The method of pulling the bag up is adopted. When changing bags, after the skeleton is pulled out, the dirty bags are put into the ash hopper at the lower part of the box and taken out from the manhole, which improves the operating conditions of bag changing.
5. The box adopts airtight design with good sealing performance. The inspection door adopts excellent sealing material, and kerosene is used for leak detection in the production process, so the air leakage rate is very low.
6. The air inlet and outlet ducts are arranged compactly, and the airflow resistance is small.