Waste gas collecting device for preparation based on dilute nitric acid and collecting method of waste gas collecting device

The invention relates to the technical field of waste gas collection, in particular to a waste gas collection device for dilute nitric acid preparation and a collection method thereof.The waste gas collection device comprises a waste gas absorption tower, two gas-liquid adsorption assemblies arranged in the waste gas absorption tower, a rotating blade arranged at the center of the bottom of the waste gas absorption tower and an S-shaped cooling pipe for cooling spraying liquid; a gas inlet cylinder is fixedly installed on one side of the bottom of the waste gas absorption tower through bolts, a gas-liquid adsorption assembly in the waste gas absorption tower comprises a filler containing disc and a spraying ring, and a second filler disc is fixedly installed on one side of the top of the gas inlet cylinder in the waste gas absorption tower through bolts. The first bevel gear on the rotating blade is driven by waste gas to rotate, the first bevel gear is meshed to drive the stirring rod and the stirring blade