For mass desoldering I have used a solder fountain. Think a giant solder pot with a pump that pumps the solder up a large tube in the center. Works very well for through hole stuff.

[Stynus] found himself in this position, the proud owner of a Weller DSX80 desoldering iron from an auction, but without its accompanying solder station required for it to work. Fortunately ...

In addition to the soldering iron and 10 interchangeable tips, it included the hot-air rework gun, a voltmeter for checking electrical circuits, and a desoldering pump for removing liquid solder.