The TRT Triplex dryer operates on the uniflow principle, i.e. material and hot gases flow in the same direction and pass through the dryer tubes from the center outwards. The material to be dried is fed into the innermost tube, it passes through the dryer and is discharged through double pendulum flaps fitted to the dust jacket. The residual moisture of the dried material is set by controlling the exhaust gas temperature and dwell time of the material in the dryer. The hot gas required is produced in a combustion chamber, using solid, liquid or gaseous fuels. Process gases can be used as well. The dryer exhaust gases pass through a filter for dust collection.