Boiler Electric Cloth Combined Dust Collector Factory Direct Central Dust Removal System

1, Working principle of bag filter for 130t boiler

The dust containing gas enters the ash hopper of each unit through the diversion pipe. Under the guidance of the ash hopper diversion system, the large particles of dust are separated and directly fall into the ash hopper. The rest of the dust enters the filtering area of the middle box with the airflow. The filtered clean gas passes through the filter bag and is discharged through the upper box, lift valve and exhaust pipe. With the process of filtration, when the dust on the surface of the filter bag reaches a certain amount, the dust removal control device will close the lifting valve according to the set procedure, open the electromagnetic pulse valve for injection, shake off the dust on the filter bag, fall into the ash hopper and discharge through the ash unloading valve.

This series of dust removers are equipped with bypass flue. When the boiler (or incinerator) is started, the bypass flue is opened to prevent the oil from burning well during ignition, and the oil sticks to the filter bag, and the filter bag will be burned in case of open fire. When the boiler accident occurs, the flue gas temperature exceeds the allowable temperature of the filter bag, open the bypass.

This series of dust remover is also equipped with leak detection device, which consists of multiple probes (one in each bin room), and an air gun is installed in the ash hopper.

2, Operation requirements of bag filter for 130t boiler

Generally, if you want a dust removal equipment to work normally, you must first make a plan for the operation of the dust removal equipment. In the operation of the dust removal equipment, the requirements in the operation of the equipment should also be considered. Therefore, Huiyang dust removal summarizes the five aspects that should be paid attention to during the operation of the dust removal equipment.

1. Pre coating must be carried out before the dust removal filter bag is put into operation for the first time, and it needs to be coated again when it is out of operation for a long time, so as to establish a surface filter bed and reduce the pollution of oil or other substances on the filter bag.

Pre coating should be carried out under the condition that the filter bag is offline, and the induced draft fan is used. The weight of ash spraying should be calculated according to about 1kg (aluminized soil) per bag, and the opening of baffle of induced draft fan should be controlled to make the air flow at 60kg. When the pressure difference of filter bag increases to 300pa, finish precoating and check the filter bag, which should be evenly coated and not show its true color.

2. Start and exit of bag filter The bag filter can be put into operation only if the following conditions are met: 120 ºC is less than the inlet flue gas temperature is less than 160 ºC, the pressure difference between the front and rear of the dust collector is greater than 300 PA, the soot blowing system is put into operation when the current back pressure difference is less than 700 PA, at least one coal mill is put into operation; the ash hopper heating device has been put into operation when the soot blowing pulse air temperature is less than 140 ºC.

Exit of bag filter = no matter what reason causes boiler shutdown, the dust collector should be removed quickly

The column is out of operation, and the bypass system is opened to avoid high temperature oxidation of the filter bag.

3. The bypass system should be put into operation under the condition of starting ignition or fully feeding oil to stabilize combustion, so as to avoid oil pollution of filter bag. When the coal seam is put into combustion, the bypass system should be withdrawn and the dust collector should be put into operation to avoid the abrasion of induced draft fan blades and emission pollution. .

4. During the adjustment of boiler combustion condition and flue gas temperature monitoring, the monitoring of boiler combustion condition and exhaust gas temperature should be strengthened to avoid high temperature flue gas entering dust collector due to abnormal combustion condition or high exhaust gas temperature. For the flue gas temperature reduction due to the deterioration of combustion conditions, timely inspection and adjustment (generally not less than 120 degrees, to avoid condensation phenomenon).

5. Setting of the parameters of the ash cleaning system and setting of the cleaning pressure: the back blowing air pressure is set to 0.08mpa during the operation, so as to reduce the damage to the filter bag and not affect the soot blowing effect.

Adjustment of dust cleaning pressure difference setting value (point) and ash cleaning frequency: for the setting of switching points of three ash removal modes (slow cleaning, normal cleaning and fast cleaning) under different dust loads of the filter bag body, the principle of minimizing the resistance of the dust collector must be followed under the premise of considering the service life of the filter bag. In practical operation, it is necessary to keep the pressure difference in a reasonable range and to keep the ash cleaning frequency as low as possible. When the pressure difference increases rapidly due to the load or other operating conditions, the interval time and pulse width of the back blowing pulse can be adjusted appropriately, and the back blowing frequency can be increased to make the pressure difference return to the normal value as soon as possible. When the pressure difference increases or the steady-state value is higher than the set point under stable working conditions, the causes should be found out in time.