| 摘要 |
<p>The invention relates to a heat exchange element (1) which is made up of a bag of a film material, such as plastic film, and to a heat exchanger made up of such heat exchange elements, the heat exchanger being suitable, for example, for the evaporation of effluents which contain solid matter, such as effluents from bleaching. The transfer of heat takes place in the bags (1) from a vapor condensing in the interior (3) of the bags to a liquid evaporating on their exterior surfaces (2). The forming evaporated vapor may be recycled via a compressor to the interior of the bags as heating vapor so that the heat exchanger will function as a distillation apparatus. According to the invention there is bonded inside the bag (1) a planar condensate-removal member, substantially narrower than the bag, for example, a circular disc (9) to which the forming condensate is arranged to flow and in which there is formed a hole (13) and at least one condensate outlet duct (8) leading to it, the film material of the bag being pierced in the area of the hole on each side of the condensate-removal member. In the heat exchanger, which has oppositely positioned bags (9) tied to form a pack, the condensate-removal members (9) are located one against another, and the apertures pierced in the film material form a condensate-collection duct common to them. The condensate-removal members being narrower than the bags enables the solid matter from the suspension being evaporated to be removed by falling through the spaces between the bottoms (10) of adjacent bags.</p> |
