Abstract: A sootblower for an economizer of the type having a vertically extending cylindrical casing in which is mounted a plurality of spiral coils arranged parallel to each other in concentric relation with respect to the central vertical axis of the cylindrical casing. The spiral coils are in the form of finned tubes, the coils being disposed in closely spaced relation but providing clearance between the fins on adjacent coils. A heat exchange fluid is conducted through the spiral coils whereby the coils can extract heat from exhaust gases passing upwardly through the economizer from a boiler.

Abstract: In a method of treating flue gas which results from the burning of coal in a boiler wherein the flue gas is passed through a wet scrubber and proceeds in a saturated condition as a flue gas stream to an exhaust fan and then up a stack to the atmosphere, and wherein a reheat heat exchanger is employed to heat the saturated flue gas prior to its introduction to the exhaust fan to a sufficiently high temperature above its dew point the improvement in that method which comprises heating at least a portion of the flue gas stream subsequent to its passage through the wet scrubber and prior to its passage through the reheat heat exchanger to prevent any condensation from the flue gas stream in or on the reheat heat exchanger.