Self cleaning heat exchanger

摘要

A self cleaning heat exchanger 10 has a bundle 12 of tubes 14 extending between two headers and through which a process liquid flows and a distributor 30 mounted within one of the headers 22 to position projectiles at a mouth of the tubes. In use, the projectiles are entrained by a process fluid to flow along the tubes and scour the inner walls of the tubes. The distributor includes a moveable arm 32 connected to a supply of projectiles and comprises a channel that faces the mouths of tubes and is arranged to fully contain projectiles to evenly distribute the projectiles into each of the tubes. The tube bundle may be rectangular whereby the arm translates across a tube plate 24 or may be circular whereby the arm is rotated by a motor 38 about a centre of the bundle. A plurality of arms, i.e. 4 may be provided and arranged as spokes in a cross 30 radiating from a common central hub 34.