摘要 |
<p>Method and device for drying of fibrous or granular material, preferably peat, in a rotary drier (2), preheated primary drying air being supplied to the drum (2) axially and substantially moisture saturated at its passage through the rotary drier (2) due to absorption of water from the material to be dried. At known drying plants preferably for peat the drying is not enough efficient and rapid, to a large extent due to the fact that too low air temperatures are used. Moreover, the drying air is usually supplied only from one direction, the heat transfer not being enough efficient. This invention is characterized in that primary drying air of a temperature of the order of 140-150oC is supplied to the rotary drier (2) axially and that secondary drying air, also having a temperature of the order of 140-150oC, is supplied to the rotary drier (2) axially after preheating. Preheating is carried out in that the secondary drying air passes past finned pipes (7), in which hot water, preferably is circulating.</p> |