Harmful gas treatment device for environmental protection engineering

The invention relates to the technical field of environmental protection engineering, and discloses a harmful gas treatment device for environmental protection engineering, the harmful gas treatment device comprises a box body, the top surface of the box body is provided with a pair of openings, the top wall of the box body is provided with an exhaust hood communicated with an inner cavity of the box body, and the box body is internally provided with purification liquid; the lifting mechanism is in transmission fit with a pair of ventilation pipes, the lifting mechanism drives the ventilation pipes to enter and exit from the inner cavity of the box body through the opening, a plurality of ventilation holes are formed in the ventilation pipes, filter screens are fixedly connected into the ventilation holes, and a collecting pipe is arranged at one end of each ventilation pipe; the first valve is communicated with an air inlet pipe, the first valve is further used for being communicated with the two ventilation