The invention provides a multi-occasional application 
waste gas purifying device for 
environmental protection engineering. The 
waste gas purifying device comprises a moving tray, moving roller wheels,a traction rod, a purifying tank, an exhaust 
chimney tube, a conveniently-connected adjustable gas inlet 
bellows structure, an electrostatic 
waste gas dust-removing box structure, a circulatable waste gas neutralizing and spraying tank structure, a waste gas purifying 
barrel structure, a flow-guiding partition 
board structure, a waste liquid recycling tank, a main partition board, a traction hole, a suction 
connection control switch, an electrostatic dust removal 
control switch, a spraying circulation 
control switch, an exhaust 
control switch, an exhaust fan and a protective hood. Through thearrangement of a waste gas inlet 
bellows, a first connecting 
flange plate, a second connecting 
flange plate, a gas inlet hood, a first connecting lug plate, an angle adjusting 
hydraulic cylinder anda second connecting lug plate, rotating adjustment of the second connecting 
flange plate through the angle adjusting 
hydraulic cylinder according to different using occasions is facilitated, and connection with a waste gas emitting port is facilitated.