Relationship between dust removal bag and back blowing of dust removal equipment
The dedusting bag can be called the heart of the bag type deduster, which is generally called the filter bag, dust bag, dust bag, dust bag, dedusting bag, deduster bag, etc. The dedusting bag is the key component in the operation of the bag filter, and usually the cylindrical filter bag is vertically suspended in the filter.
The back blowing volume of dust removal bag is an important technical parameter of the back blowing bag filter. Whether it is positive pressure or negative pressure, the air permeability of the dedusting bag becomes worse before it is cleaned. Therefore, after a period of time, as long as the gas in the filter bag is extracted (or pressed out), the filter bag can be deflated to realize back blowing and back washing. When calculating the back blowing volume of the chamber type back blowing bag type dust remover, the time is set as T, and the required back blowing volume is calculated according to the following formula: Q=3600 kNV/T If the gas in the bag chamber filter bag to be cleaned is pumped out (or pressed out)
In the formula, Q=blowback volume, m/h;
N=number of filter bags to be cleaned in a bag room;
V=volume of each filter bag, m;
K=air leakage coefficient, 1.2-1.3;
T=time for bag shrinkage and ash removal, generally 10-30 seconds.
The total pressure P of the reverse suction fan is generally 1.5-2 times of the inlet manifold pressure of the dedusting equipment. The reverse suction fan can be selected according to the above air volume and pressure, but the influence of the air temperature in the reverse suction pipe on the fan performance shall be considered when selecting, and shall be corrected in the calculation.
Practice has proved that the filter bag can only be deflated by back blowing (suction). Generally, 10-20s is appropriate for back blowing (suction) air. During the dust removal, it is generally necessary to carry out the dust removal for several times continuously, so as to make the filter bag appear several times of "air inflation air deflation air inflation air deflation", so as to achieve better dust removal effect.