What is the function of bag filter in waste gas purification?

Incineration fly ash and garbage incineration slag collected by dust removal equipment shall be collected, stored and transported separately. Fly ash should be treated as hazardous waste while slag should be treated as general solid waste. The fly ash collected by the dust collector is sent to the ash hopper for storage after humidity adjustment, and then sent to the landfill. Because fly ash contains a lot of heavy metals and organic pollutants, it belongs to hazardous waste and must be solidified or stabilized before landfill. Smoke and dust are mainly non-combustible substances and combustion products entrained in smoke. The combustible components in garbage will form black smoke due to incomplete combustion. Black smoke contains a large number of carbon particles, and heavy metals harmful to human body are mainly concentrated in particles smaller than 3 μ m. According to data, in the mid-1970s, the lead content in dust discharged from Chicago garbage incinerator reached about 6. The content of solid lead with particle size less than 2μm is more than 95%. Because the compounds usually present in the flue gas are contained in the ashes and other residues of the incinerator, the fly ash and bottom ash should be properly treated.

Flue gas purification system is the key to pollution control of municipal solid waste incineration. The flue gas pollutants from garbage incineration exist in gaseous or solid form, which are generally divided into four categories: acidic gaseous pollutants, incomplete combustion products, particulate pollutants and heavy metal pollutants.

The emission concentration of various pollutants after flue gas purification should reach the national standard GWKB3 -2000. Flue gas purification should adopt semi-dry process and bag dust removal process, which are divided into two steps: the first step is to remove acid and acid gas; The second step is dust removal, collecting particulate matter, heavy metals and dioxins.

Dust collector is the terminal equipment of flue gas purification system. The collection effect of electrostatic precipitator on fine particles in flue gas is not as good as that of bag filter, and its optimal working temperature is the optimal temperature for dioxin synthesis. The national standard GB 18485-200 1 stipulates that the dust removal device of domestic waste incinerator must adopt bag filter. Bag filter can not only collect ordinary particles, but also remove volatile heavy metals or their chlorides, sulfates or oxides to condense into diameters less than or equal to 0. 5 microns, and can also collect organic pollutants such as dioxins adsorbed on ashes or activated carbon particles. If you still don't understand, you can contact Yang Gong, the dust removal technology department of Botou City, Tong Ming.