Abstract: A heat exchange element of flexible plastic film, a heat exchanger including such elements, and apparatus for manufacturing the elements. The element includes a pair of opposite film sheets bonded by welds to form an expandable bag with inside and outside heat exchange surfaces, an inlet opening for supplying a pressurized heat exchange fluid to the bag, an outlet opening for discharging the fluid from the bag after heat exchange, and an array of welds defining routes for fluid flow inside the bag. There are spot welds in a first zone of the element, parallel extended welds in a second zone of the element, defining fluid flow channels through the second zone, and oblique welds in a third zone of the element, defining channels for fluid flow towards the outlet opening. The heat exchanger includes adjacent elements for heat exchange between a pressurized first fluid.

Abstract: The invention provides a multi-component homogenous co-crystallized low sodium salt product for food and pharmaceutical use. The salt product of the invention is essentially segregation-free, has low hygroscopicity and is free-flowing. It has good microbial depression properties and good taste. It supplies the functionality of salt (NaCl) in processed foods and it also maintains the microbial safety, nutritional value and taste. The salt product of the invention includes an alkaline and alkaline earth metal chloride component and an ammonium chloride component. An alkaline metal is potassium (K), and optionally also sodium (Na). An alkaline earth metal is Magnesium (Mg) or Magnesium (Mg) and Calcium (Ca) having the sum of the molar ratios 1. The invention provides also a process to produce the salt products of the invention.

Abstract: A heat exchange element of flexible plastic film, a heat exchanger including such elements, and apparatus for manufacturing the elements are described. The element includes a pair of opposite film sheets bonded by welds to form an expandable bag with inside and outside heat exchange surfaces, an inlet opening for supplying a pressurized heat exchange fluid to the bag, an outlet opening for discharging the fluid from the bag after heat exchange, and an array of welds defining routes for fluid flow inside the bag. There are spot welds in a first zone of the element, parallel extended welds in a second zone of the element, defining fluid flow channels through the second zone, and oblique welds in a third zone of the element, defining channels for fluid flow towards the outlet opening. The heat exchanger includes a pack of adjacent elements for heat exchange between a pressurized first fluid.

Abstract: The invention relates to a method for evaporating a solution and an evaporator applied to it. The evaporator (1) has parallel plate heat exchanger elements (3) fitted inside a jacket (2), consisting of a flexible plastic film, for example, and a liquid distribution space (4) common to the elements, from where the solution to be evaporated can be spread, through supply channels (6), on the heat transmission surfaces (4) of the elements to run from the top downwards. The solution (10) that has not evaporated on the surfaces is recycled from the bottom of the evaporator back to the liquid distribution space, and from there to the heat transmission surfaces (4) of the elements for re-evaporation. In connection with evaporation, precipitate is separated from the solution as a result of over-saturation, ending up in the recirculation flow with the solution and being separated from the solution in the liquid distribution space (14) that works as a separator for the precipitate.

Abstract: A heat exchanger transfers heat between gas flows principally directed counter current, the walls of the heat exchanger separating the flows from each other being made from flexible film through which the heat transfer takes place. The heat exchange elements are attached to each other by welding so that no rigid side-walls are required. The heat exchanger can be folded especially for packaging, transport and installation.

Abstract: A method including evaporating aqueous solutions containing ammonia, adding an acid to the evaporated vapor flow to form an ammonium salt, and condensing the vapor flow to form a liquid containing the salt. By this method the ammonia formed into a salt is not present as an inert gas layer which would impede condensation on the condenser surfaces.

Abstract: The object of the invention is a heat exchanger (1) for transferring heat between gas flows directed principally counter current, the walls of the heat exchanger (1) separating the flows from each other being flexible film (3), through which the heat transfer takes place. The heat exchange elements (2) are attached to each other by welding so that no rigid side walls are required. In this case, the heat exchanger (1) can be folded especially for packaging, transport and installation.

Abstract: The invention relates to a heat exchange element (1) for a film heat exchanger intended for distillation or for the evaporation of solutions or suspensions, and to a method for manufacturing the same. The substantially bag-like element is formed by bonding from oppositely positioned plastic heat exchange films (2), evaporation of liquid taking place on the exterior surfaces of the films and condensing of the obtained vapor taking place on the interior surfaces. In the bonding the interior (4) of the element is divided into ducts to direct the travel of the vapor, and according to the invention the films are at the same time stretched in the intervals between the bonding points (3) in order to provide leeway for bulging during the pressurization of the interior of the element.

Abstract: 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.

Abstract: A liquid distributor for distributing liquid over the heat transfer surface of an evaporator includes a channel array including one or more supply channels and downwardly deviating distribution channels. Each distribution channel has a step-shaped expansion located downstream with respect to the supply channel and connecting therewith via a sharp point, restricting the liquid suction created in the distribution channel. Sharp points provided in the supply channel or channels further restrict the liquid suction.

Abstract: The method relates to a film heat exchanger and a method for constructing the same. The heat exchanger comprises bags (1) made of film material in order to transfer heat from the steam to be condensated inside the bags to the liquid to be evaporated on the outer surfaces (18) thereof, as well as feed channel arrays for distributing steam (10) and liquid onto the internal and external heat transfer surfaces of the bags. According to the invention, inside the top end (2) of each bag (1), there is provided an essentially straight strip (11) bordering the steam channels (10), to which strip the bag is fastened; in connection with the fastening, the top edge of the bag is pulled straight by bending the bag, so that the middle part of the bag is raised in relation to the sides (12) thereof, and the thus straightened edge is then attached to the strip provided inside the bag.

Abstract: A liquid distributor in an evaporator, intended in particular for the evaporation treatment of liquid suspensions which contain fibers or other such solid ingredients. The distributor comprises, located at the upper end of the heat exchange surface, a transverse frame, liquid conduits disposed therein distributing the liquid over the entire width of the heat exchange surface. According to the invention the liquid conduits are made up of feed conduits slanted obliquely downwards and of distribution conduits branching out therefrom and leading to the heat exchange surface. At the branching points of the conduits their wall surfaces on the downstream side with respect to the feed flow are rounded into curved dividing surfaces by means of which the dividing of the flow is carried out.

Abstract: The invention relates to a heat exchanger wherein the heating vapor is fed onto heat exchange surfaces of membrane material from a vapor distributor, the vapor distributor having parallel conduits for directing vapor over the entire width of the surfaces. According to the invention the vapor distributor is made up of two opposing wall elements which are fastened to each other by means of projections in one element and corresponding recesses in the other element. The upper end of the membrane constituting the heat exchange surface is locked between the projections and recesses that are fastened to each other. Thus, pleats are produced in the membrane as an expansion leeway for the vapor space delimited by the membrane.