TOWER GRAIN DRYER WITH IMPROVED HEAT RECLAMATION AND COUNTER-FLOW COOLING SECTION

摘要

A grain drying tower comprises a heater and blower separating a heating plenum and a cooling plenum. The dryer is provided with a heat reclamation/heat recycling system and/or counter-flow cooling to reduce the energy requirements of the tower dryer. The heat reclamation system comprises a chamber external to the outer wall of the tower and which is and located at a point along the drying path. The bottom of the chamber is open to the atmosphere. Hot exhaust air enters the heat reclamation chamber at the top of the chamber and is drawn back into the tower by the blower as the exhaust air exits the open bottom of the chamber. In the counter-flow, the walls defining the grain path of the in the cooling section are not air permeable, and air is drawn into the cooling section through outer wall ducts which are closed at the inner wall. The entering air travels up through heated grain to be warmed, and then enters the plenum through inner wall ducts, which are closed at the outer wall of the tower.

主权项

1. A tower dryer for drying grain, the tower drying comprising:
an upper drying section comprised of an inner wall and an outer wall surrounding said inner wall; said inner and outer walls both being air permeable; said inner and outer walls, in combination, defining a grain drying flow path; said inner wall defining a drying section central plenum; a lower cooling section comprised of an inner wall and an outer wall surrounding said inner wall; said inner and outer walls, in combination, defining a grain cooling flow path; said inner wall defining a cooling section central plenum; said cooling section walls being made from an air-impermeable material; a plurality of outer wall ducts extending into said grain cooling path from said cooling section outer wall and being open at said outer wall; a plurality of inner wall ducts extending into said grain cooling path from said cooling section inner wall and being open at said inner wall; said outer wall ducts and said inner wall ducts all being at least partially open at their bottoms; a blower and heater positioned between said cooling section center plenum and said drying section center plenum; said blower and heater being arranged to force heated air into said drying section center plenum; whereby, ambient cooling air is drawn into said grain cooling column through said outer wall ducts, said cooling air travels upwardly through the grain within the cooling column and enters said inner wall ducts, said cooling air entering said cooling section center plenum through said inner wall duct.