Closed dust removal system for boiler slag bin

The utility model discloses a closed dust removal system for a boiler slag bin. The closed dust removal system for the boiler slag bin comprises a negative pressure generation mechanism, a conveying pipeline (2) communicated with the negative pressure generation mechanism, a dust outlet (3) formed in the pipeline, a dust blocking ventilation mechanism (4) arranged on the pipeline, and a dust suction opening (5) installed at the other end of the conveying pipeline (2). The dust suction opening (5) is arranged in the slag bin, the dust outlet (3) is arranged above a steel belt conveyor (7) of a boiler, and the dust blocking ventilation mechanism (4) is detachably arranged in the position, with the dust outlet (3) of the conveying pipeline (2). Through negative pressure generated by the negative pressure generation mechanism, raised dust in the slag bin is recovered and conveyed to the position above the steel belt conveyor, and thus the amount of the raised dust in the slag bin is effectively reduced. Meanwhile, the negative pressure generation mechanism is formed through negative pressure in a furnace chamber of the boiler and negative pressure in a flue, energy is saved, energy on different workshop sections in a boiler factory can be utilized complementarily, and the existing problem of raised dust in the slag bin is effectively solved.