Packed tower

A packed tower for treating an effluent stream comprising a fluid and particles from an abatement apparatus, said packed tower comprising:

• a packed tower housing having
• an inlet for receiving said effluent stream;
• an outlet for venting said effluent stream;
• a packed substrate housed within said packed tower housing between said inlet and said outlet, said packed substrate being configured to entrain at least some of said particles from said fluid as said effluent stream flows therethrough;
• and
• a fan housed within said packed tower housing, said fan being configured to propel said effluent stream from said inlet towards said outlet and to remove at least some of said particles from said fluid, said fan comprising an axial centrifugal fan having a centrifugal impeller and at least one aperture configured to convey a tower fluid, wherein a force generated from conveying said tower fluid from said at least one aperture causing said fan to rotate and wherein the centrifugal fan further comprises an annular fluid bearing.