Abstract: An apparatus for washing gases and/or recovering heat therefrom, which apparatus includes a cylindrical treatment vessel (1) having at the bottom thereof a gas inlet (3) connected to a gas supply line (2) and at the top thereof a gas outlet (4) for processed gas; a vertical rotatable center shaft (5) which carries at least one cup-shaped rotary body (6) having a plurality of openings (7), preferably vertical slots, in the side wall (8) thereof; respective means (9, 10) cooperating with each of said rotary bodies (6) for introducing liquid to at least one location within said at least one rotary body (6); and a liquid outlet (11) at the bottom of the vessel. The liquid introduced into the rotary body or bodies (6) is thrown as curtains of liquid through the openings (7) against the walls of the treatment vessel by rotating the rotary body or bodies (6).