A heat exchanger (1; 1*; 100) includes a bundle of tubes (8), each extending in a respective elongation direction (X1) and defining a flow path for a working fluid that extends in the elongation direction, wherein each tube (8) of the bundle of tubes can be supplied with a working fluid; a matrix (6) of thermally conductive material that houses the tubes (8) of the bundle and that is configured, in use, for promoting heat exchange between working fluids that run through corresponding tubes (8) of the bundle; and a shell (4) made of thermally insulating material arranged around the matrix (6), wherein: the matrix (6) is made up of a plurality of sections (10; 10*) arranged aligned in the elongation direction (X1) and alternated by thermal interruptions (12) that extending transversely to the elongation direction (X1).