| 摘要 |
<p>An air treatment plant comprises a housing (1); a conveyor (4) adapted to feed food to be processed through an inlet opening (2) in the housing, to and through an air treatment area, and to feed the processed food from this area to and through an outlet opening (3) in the housing; a heat exchanger; and a circulation fan for generating a circulating air flow through the heat exchanger, the air treatment area, and the circulation fan in succession. A pressure regulating fan (25) is connected to a chamber (33) adjacent to one of the inlet and outlet openings (2, 3) for generating a pressure difference across that opening substantially equal to that across the other opening, thus minimising the air exchange between the interior and the exterior of the housing (1). The conveyor (4) inwardly of this one opening passes a tunnel with at least two air curtain ducts which are directed substantially transversely of the conveyor path and through which some of the circulating air flows.</p> |
