Drying of grain in the mode of the gushing layer

Gushing is essentially a special case of channeling, an example of the rational use of this undesirable phenomenon for the organization of contact between the drying agent and grains with a stable and intensive circulation of grain material. The real difference between gushing and other cases of channeling is the intensive circulation of the material, facilitated by the proximity of the walls, the friction of the material against which is small compared, for example, with internal friction in the layer surrounding a conventional channel. Gushing is channeling in a conical apparatus. (The purpose of the study) To increase the efficiency of the technological process of drying grain piles by improving the design of the dryer with a gushing grain layer and substantiating the main technological parameters. (Materials and methods) The design of a grain dryer with a gushing grain layer is proposed. The working chamber of the dryer consists of a drying and cooling parts. For a gushing layer, the critical transition rate from a dense layer to a gushing layer is higher than the reverse transition rate. The transition from a dense layer to a gushing (or channeling) occurs through the stage of short-term fluidization of a certain amount of grain material, since for a through channel breakthrough, it is necessary to acquire minimal grain mobility in the breakthrough zone. (Results and discussion) Studies of drying grain material with an oscillating mode have been carried out, which allows, due to alternating cycles of heating and cooling of grain, to prevent its overheating, to preserve agricultural and sowing qualities. (Conclusions) When designing grain dryers of the gushing layer, it should be limited to the interval of drying agent speeds from 2 to 3 m/s.