Selection basis of bag filter
Date:2021-11-10 13:15:35
Author:admin
Views:
206
Bag type dust collector is a kind of dry dust filtering equipment, which is mainly used for flue gas purification, dust treatment (non-fibrous) and material recovery in industries such as cement, metallurgy, building materials, machinery, chemical industry and electric power. The core part of the entire dust removal work is a series of filter bags installed inside the box. The filter bags are made of woven filter cloth or non-woven felt. When the dust-containing gas enters the dust collector through the air inlet, the fiber fabric is filtered. The particles in the gas are filtered under the action, and the dust with large and specific gravity settles down due to its own gravity and falls into the ash hopper. The fine dust particles are blocked when the gas passes through the filter bag, so that the gas is purified and Prescribed emission standards.
For the dusty gas produced under different production conditions, a suitable type of dust collector should be used for purification treatment, so as to achieve the best purification effect. If the equipment is too large, it will cause unnecessary waste. Small, will affect production and fail to meet environmental protection requirements. The main selection basis is as follows:
1. Temperature of dusty gas
The temperature of the dusty gas is the main basis for the selection of the dust collector. If the intake air temperature is different from the design temperature, it will cause serious consequences. When the gas temperature is too high, the filter bag will be burned and deformed. For high-temperature gas, it must be cooled below the temperature that the filter material can withstand. Condensation will occur when the gas temperature is too low, so the gas temperature must be kept above 20 ° C.
2. Handling air volume
The air volume is the volume of gas that the dust removal equipment can purify in a unit time. Units are cubic meters per hour m3 / h or standard cubic meters Nm3 / h per hour. This is one of the main reasons for the selection of dust collectors.
3.Inlet dust concentration
It refers to the dust concentration in the gas at the air inlet, which is determined by the production process of the dust point. In the selection, it is an important factor behind the air volume. The unit is g / m3 or g / Nm3. When the dust concentration at the inlet is too large, consideration should be given to the installation of pre-dust removal equipment.
4.Dust concentration at the outlet
It refers to the discharge concentration of the dust collector, which is the same as the expression method of the dust concentration at the inlet. It is mainly determined by the local environmental protection emission requirements and user requirements. The exhaust gas concentration after the purification treatment of the dust collector can generally reach 50g / Nm3.
5.Pressure loss
It refers to the pressure drop, or resistance, of the gas from the inlet to the outlet of the dust collector.
6.Operating pressure
The operating pressure of the bag type dust collector is determined based on the static pressure value of the micro fan before and after the dust collector and its installation position, and it is also the design pressure value of the bag type dust collector.
7.Filter speed
Filtration speed is an important factor in the design and selection of a bag filter. Its definition is the speed of the filtered gas when passing through the filter material, or the ratio of the air volume of the filter material to the area of the filter material. The unit is m / min.
