| 摘要 |
PCT No. PCT/AT88/00007 Sec. 371 Date Jul. 27, 1989 Sec. 102(e) Date Jul. 27, 1989 PCT Filed Aug. 2, 1988 PCT Pub. No. WO88/05632 PCT Pub. Date Aug. 11, 1988.For drying or ripening foodstuffs with unsaturated air, the surrounding air and the exhaust air are mixed in a proportion such that the degree of humidity of the inlet air is obtained with a minimum consumption of energy. A cooler (21), a heater (22) and a fan (29) are provided in the inlet air duct (20). A linking duct (35) extends from the exhaust air duct (32) to the inlet air duct (20). All three ducts contain individually adjustable butterfly valves (30), a second fan (33) being arranged in the exhaust air duct (32) before the branching off point of the linking duct (35). Temperature and humidity measuring sensors (38,39) for the surrounding air and the outer air determine the proportion of their mixture, exclusively aimed at ensuring the desired relative humidity of the inlet air. Preferably the exhaust air duct (32) has a second cooler (34), and the quantity of heat gain in each cooler (21,34) is used to heat the inlet air when its relative humidity has to be changed. |
