Method and device for recovering waste heat in preheating unit of hot oil boilers

摘要

The object of this invention is to provide a method and device for recovering waste heat in a preheating unit of hot oil boilers. The device of this invention has air feed pipes (3) transversely set in the body (1) of a boiler. Shielding rings (5), each having a cutout (4), are circumferentially mounted around the body (1) at regular intervals, with the cutouts (4) alternately positioned at the top and bottom portions of the body (1). The boiler body (1) is housed in an outer casing (6) to define a channel (7) by the rings (5) and the casing (6). The outer casing (6) is covered with an insulating cover (8). An air guide pipe extends from the outlet end of the channel (7) to a burner inside the boiler body (1), thus feeding hot air from the channel (7) to the burner and recovering waste heat.