The dust removal effect of the bag filter depends on ten factors, which directly affect the purification effect and life of the bag filter.
(1) Selection of filter bag: The filter bag should be made of wear-resistant and high-temperature resistant materials, such as glass fiber cloth/felt, NOMEX, needle-punched felt, P84 needle-punched felt, etc. Due to factors such as cost, NOMEX needle felt is generally used in the copper chemical industry.
(2) Temperature control: Generally, the filter bag can withstand a temperature of 200 °C, so the inlet temperature of the treatment facility should be controlled below 200 °C. When the flue gas after passing through the long smoke pipe reaches the dust collector box, the temperature can be reduced to 200 °C. Below ℃, in special cases, water cooling can be carried out, and a cooler is installed at the main smoke pipe.
(3) Fan selection: The induced draft fan is better than the blower.
(4) Mechanical dust removal is more convenient and cleaner than manual dust removal, but the cost of mechanical dust removal is high, and most of the pulse dust removal methods are used now.
(5) Air leakage and resistance: Theoretically, the dust removal efficiency of the bag filter is 99%, but it cannot be achieved in actual measurement, mainly due to the influence of air leakage and resistance. The lower the air leakage rate, the better the dust removal effect; the resistance has a certain effect on the dust removal effect. Influence, often empty the filter bag, reduce resistance, can improve the dust removal effect.
(6) The dust collecting hood should be as close to the furnace head as possible to make it easier for dust to enter the hood, increase the amount of dust collected, and reduce unorganized emission pollution.
(7) Equipment maintenance: The equipment and cloth bags are easily damaged, and the cloth bags should be repaired and replaced in time.
(8) Air velocity: The dust removal effect is the best under the air velocity of 1 to 3 m/s, and the general air velocity is controlled at 2 to 4 m/s.
(9) Filtration area: The larger the filter area, the higher the dust removal efficiency, but the cost will increase accordingly. Therefore, the air volume should be pre-calculated, and then the corresponding dust collector model should be selected.
(10) Secondary dust removal: a settling chamber is installed in front of the dust collector box to form secondary dust removal. The settling chamber can remove a part of the large particle dust, reduce the temperature and reduce the pressure of the dust collector.
