How to Solve the Air Leakage Problem of Boiler Baghouse Dust Collectors?

As a high-efficiency dust removal device, boiler baghouse dust collectors are widely used in industrial waste gas dust removal across various sectors, including light industry, machinery manufacturing, building materials, chemical engineering, non-ferrous smelting and iron and steel enterprises. Compared with electrostatic precipitators, they feature a simpler structure, lower investment and stable operation, and can also recover dust with high specific resistance that is difficult to collect by other means. In contrast to Venturi scrubbers, they consume less power, the recovered dry dust is convenient for comprehensive utilization, and there is no slurry disposal issue. Therefore, it is suitable to use baghouse dust collectors for purifying fine and dry dust.

Poor sealing at the joints between the housing and pipelines of a boiler baghouse dust collector can easily cause air leakage, which reduces the actual air volume and seriously impairs the dust removal effect and efficiency. The cold air drawn in through air leakage will increase the processing air volume of dust-laden gas and lower its temperature, leading to the generation of condensed water. Both of these factors will alter the dew point of dust-laden gas and result in condensation.

Measures to Address Air Leakage in Boiler Dust Collectors

(1) To inspect air leakage in a boiler baghouse dust collector, an inspection hole can be drilled near the air outlet. If air leakage points cannot be identified with the naked eye, turn on the exhaust fan, reduce the air damper and conduct an inspection. A hissing sound indicates an air leakage point, which should then be welded shut. Replace the rubber hoses of the ash cleaning solenoid valves and lift valves to prevent air leakage.

(2) During the fabrication and installation of the dust collector, relevant welding standards must be followed to avoid missing or insufficient welding.

(3) The discharge device shall have good sealing performance, with electric or pneumatic air lock valves being the main options currently in use. Double-layer air lock devices should be adopted if necessary. Generally, the air leakage rate of baghouse dust collectors shall be controlled at ≤3%.

(4) Enhance the thermal insulation measures for the baghouse dust collector: Thermal insulation must be applied to the dust collector housing, usually using aluminum silicate boards, rock wool boards or perlite boards. These insulation materials feature low thermal conductivity, excellent thermal insulation performance and low water absorption, with the thermal conductivity generally controlled at 0.23W/(m·K). The thickness of the insulation layer shall be determined according to the installation location and the annual local temperature changes.