What are the common dust removal equipment for coal-fired boilers?

Commonly used dust removal equipment of SZL boiler includes multi-tube dust collector, wet scrapper and bag filter.

1. Multi-tube dust collector: XTD type vertical ceramic multi-tube dust collector has the advantages of wear-resistance, high temperature resistance, corrosion resistance, low cost, etc. Its collection efficiency is not less than 95%, resistance is not higher than 900Pa and mainly removed dust granularity is greater than 20um.

Design, manufacture and acceptance of multi-tube dust collector are according to Multicyclone for Industrial Boilers HJ/T286-2006 and Technical conditions of Cyclone Dust Collector for Industrial Boilers JB/T8129-2002.

2. Wet scrapper: XL type wet scrapper has single drum and double drum two kinds which can separate gas and steam by inertial separation and water film wash and adsorption. Its collection efficiency could be 92-98%, drum resistance is 700Pa, and venturi resistance is 1200Pa. Flue gas desulfurization can be carried out by using alkaline water for flue gas cleaning.

Design, manufacture and acceptance of wet scrapper are according to Specification for Granite Wet Flue-gas Desulphurization & Precipitator Device HJ/T319-2006.

3. Bag filter: SZL boiler adopts pulse bag filter whose collection efficiency is up to 99% and resistance is lower than 1500Pa. It uses compressed air pulse to clean dust.

Temperature endurance, filtration efficiency, air permeability and strength are the important quality indexes of bag filter and also are the important factors of price.

Manufacture and acceptance of bag filter are according to Steel Welded Atmospheric Pressure Vessels JB/T4735-1997 and Specification for Bag House GB/T6719-2009.

In order to meet flue gas discharging standards in the different areas, double-step dust removal is generally used to reduce the particle content in flue gas. With double-step dust removal of multi-tube dust collector and wet scrapper, flue gas particle content can be controlled to lower than 100mg/m³ while with double-step dust removal of multi-tube dust collector and bag filter, flue gas particle content can be controlled to lower than 30m/m³ and can be controlled to lower than 20m/m³ by using coated dust bag.