Selection basis
The work of the dust collector not only directly affects the reliable operation of the dust removal system, but also relates to the normal operation of the production system, the environmental sanitation of the workshop plant and surrounding residents, the wear and life of the fan blades, and the economically valuable materials. Recycling issues. Therefore, the dust collector must be properly designed, selected, and used. When choosing a dust collector, one must fully consider the investment and operating costs, such as dust removal efficiency, pressure loss, reliability, an investment, floor space, maintenance management and other factors, according to the physical and chemical properties of smoke, characteristics and production process requirements, targeted Select the dust collector.
1. According to the requirements of dust removal efficiency
The precipitator selected must meet the requirements of the emission standards.
Different dust collectors have different dust removal efficiency. For dedusting systems with unstable operating conditions or large fluctuations, attention must be paid to the effect of changes in the amount of flue gas treatment on the dedusting efficiency. In normal operation, the order of the efficiency of the dust collector is: bag filter, electrostatic precipitator, venturi dust remover, water film cyclone dust remover, cyclone dust remover, inertial dust remover, and gravity dust remover
2. According to the nature of the gas
When choosing a dust collector, the air volume, temperature, composition, and humidity must be considered. The electrostatic precipitator is suitable for the purification of flue gas with large air volume and temperature <400°C. The bag filter is suitable for the purification of flue gas with temperature <260°C, and is not limited by the amount of flue gas. When the temperature is ≥260°C, the flue gas The bag filter should be used after cooling and cooling. The bag filter should not be used for the treatment of smoke with high humidity and oil pollution. The flammable and explosive gas purification (such as gas) is suitable for the wet dust collector; the treatment volume of the cyclone dust collector is not suitable. Limited, when the air volume is large, multiple dust collectors can be used in parallel; when it is necessary to remove dust and purify harmful gases, spray towers and cyclone water film dust collectors can be considered.
3. According to the nature of dust
Dust properties include specific resistance, particle size, true density, scooping, hydrophobic and hydraulic properties, flammability, and explosion. The electrostatic precipitator should not be used for the dust with too large or small specific resistance, and the bag-type precipitator is not affected by the specific resistance of the dust. The effect of the concentration and particle size of the dust on the efficiency of the electrostatic precipitator is more obvious, but it has an effect on the bag precipitator. Not significant; when the gas dust concentration is high, the pre-dust removal device should be set before the electrostatic precipitator; the type of bag filter, cleaning method and the filtration speed depends on the nature of the dust (particle size, scoop); wet The dust collector is not suitable for the purification of hydrophobic and hydraulic dusts: the true density of dust has a significant influence on gravity dust collectors, inertial dust collectors and cyclone dust collectors; for newly attached large dust, it can easily lead to dust collector work surface cat knots. Or clogging, therefore, it is not advisable to adopt dry-type dust-removal; when the dust is purified and met with water, it can produce combustible or explosion-risk mixture, and wet-type dust remover shall not be used.
4. According to pressure loss and energy consumption
The resistance of the bag filter is greater than that of the electrostatic precipitator, but the contrast between the overall energy consumption of the filter and the energy consumption of the two is not much different.
5. According to equipment investment and operating costs
6. Water saving and antifreeze requirements
Areas where water resources are scarce are not suitable for wet scrubbers; in the north, there is a problem of winter freezing, and wet scrubbers are not used as much as possible.
7. Dust and gas recycling requirements
When the dust has a recovery value, dry dust removal is recommended. When the dust has a high recovery value, a bag filter should be used. When the purified gas needs to be recycled or purified, the air should be recycled. Efficient bag filter.