using the example above additional catalyst can be injected into the gas turbine exhaust upstream of the heat transfer surface and can be deposited on the finned surface of the heat exchanger this may also be a powder coating and electroplated by electrostatic precipitation by electrically charging the heat transfer finned surface a solar centaur gas turbine exhaust requires waste heat recovery for heating a thermal fluid and also requires nox reduction based on the following design the heat recovery will occur in two coil sections with scr catalyst bed between a single two fluid spray nozzle is used for nh3 injection the exhaust exits the gas turbine at 860 f and enters the hot heat exchange zone where it is cooled to 617 f upon exiting the hot heat exchange zone the dilute nh3 is injected into the exhaust stream which then flows to the catalyst zone the catalyst zone is a honeycomb matrix with v2o5 tio2 based catalyst the nox reacts with the nh3 forming water and n2 the exhaust then flows to the cool heat exchange zone and is further cooled to 386 f while heating the thermal fluid the v2o5 tio2 based catalyst is applied to at least a portion of the heat transfer surface and the hot and cold heat transfer zones can be combined if desired the.