Abstract: A heat exchange device effectively collects heat in a device, in which high temperature occurs, such as a scrubber. The heat exchange device includes a first heat exchange unit having a reactor positioned on the center thereof and having a first passage, which is arranged to enclose the reactor and discharges a first gas generated in the reactor, and a second passage, which is arranged adjacent to the first passage and introduces a second gas introduced from the outside. A second heat exchange unit is installed to enclose the first heat exchange unit and having a third passage, which is connected to the first passage and receives the first gas from the first passage to discharge the first gas to the outside, and a fourth passage, which is arranged adjacent to the third passage and introduces the second gas introduced from the outside into the second passage.