A device (16) for separating particles (MP) from a flue gas flow (F) has a horizontal flue gas duct (18), through which the flue gas flow (F) is passed substantially horizontally from a first position (P1) to a second position (P2). In the first position (P1), the device (16) has a baffle arrangement (32), which comprises at least one plate (34, 36, 38) which is arranged in the flue gas duct (18) and which is inclined so as to deflect particles (MP) down to the lower portion (42) of the horizontal flue gas duct (18). In the second position (P2), the device (16) has a collecting means (40), which is arranged in the lower portion (42) of the flue gas duct (18) to collect the particles (MP) which have been deflected downwards by the plate (34, 36, 38) to the lower portion (42) of the flue gas duct (18).