A heat exchanger (10) of heat pipe configuration for transferring heat between a first and second process streams via a heat transfer fluid comprises: at least one first process stream passage (19); at least one second process stream passage (29); and a shell (11) enclosing the first and second process stream passages (19, 29) within a volume (55). The volume (55), as a result of a heat transfer process, is fully filled with both vapour and liquid phases of the heat transfer fluid. The first and second process stream passages (19, 29) are spaced by a disengagement zone (50) enabling gravitational separation of said vapour and liquid phases and limiting accumulation of liquid phase heat transfer fluid about the first process stream passage(s) (19). Such heat exchangers can be used, among other applications, to replace a flash cooling stage in a Bayer process plant.

A thermal retention apparatus includes a tank and a phase change thermal energy storage unit contained within the tank that, in turn, includes a phase change material and a heat exchanger assembly. The heat exchanger assembly includes a phase change material (PCM) charging circuit for charging the phase change material, and a PCM discharging circuit for discharging the phase change material. The heat exchanger assembly includes a plurality of heat exchanger modules immersed within the phase change material, and the PCM charging circuit includes a fluid flow arrangement of the heat exchanger modules that is in parallel. The PCM discharging circuit includes a fluid flow arrangement of the heat exchanger modules that is in series.

A thermal retention apparatus includes a tank and a phase change thermal energy storage unit contained within the tank that, in turn, includes a phase change material and a heat exchanger assembly. The heat exchanger assembly includes a phase change material (PCM) charging circuit for charging the phase change material, and a PCM discharging circuit for discharging the phase change material. The heat exchanger assembly includes a plurality of heat exchanger modules immersed within the phase change material, and the PCM charging circuit includes a fluid flow arrangement of the heat exchanger modules that is in parallel. The PCM discharging circuit includes a fluid flow arrangement of the heat exchanger modules that is in series.

A thermal retention apparatus includes a tank and a phase change thermal energy storage unit contained within the tank that, in turn, includes a phase change material and a heat exchanger assembly. The heat exchanger assembly includes a phase change material (PCM) charging circuit for charging the phase change material, and a PCM discharging circuit for discharging the phase change material. The heat exchanger assembly includes a plurality of heat exchanger modules immersed within the phase change material, and the PCM charging circuit includes a fluid flow arrangement of the heat exchanger modules that is in parallel. The PCM discharging circuit includes a fluid flow arrangement of the heat exchanger modules that is in series.

A modular thermal apparatus for performing transformation between thermal and acoustic energy is disclosed and includes a housing, first and second fluid ducts extending therethrough, and a regenerator having axially extending regenerator fluid passages. A first heat exchanger conducts thermal energy in the axial direction and includes transversely oriented fluid passages extending through a thermally conductive body and changing direction within the body to terminate axially aligned with the regenerator fluid passages. The apparatus also includes a second heat exchanger having fluid passages extending through a thermally conductive body and terminating in fluid communication with the regenerator fluid passages. Thermal energy is transferred between the heat exchangers and an external thermal energy source or sink. The housing withstands a pressure associated with a pressurized working gas and the fluid ducts provide for connection of the apparatus as a module within an acoustic power loop.

There is provided a large-sized reboiler that can achieve space saving and reduction in plant cost. Specifically, there is provided a large-sized reboiler comprising a vessel of which a liquid is supplied from a lower part and a vaporized gas is discharged from an upper part; and a heat transfer tube group arranged in such a manner that a void penetrating in the up-and-down direction is formed in the vessel, wherein a maximum length of a cross-sectional figure of a flow path for the liquid exceeds 2 m, and the void occupies 5 to 10% of an area of the cross-sectional figure of the flow path.

There is described a heat exchanger comprising a plurality of tubes arranged parallel with each other in order to form one or more tube bundles axially inserted into a shell. A first fluid, fed through one or more first inlet nozzles flows inside the tubes and a second fluid, fed through at least one second inlet nozzle, flows inside the shell in order to perform the heat exchange with the first fluid through the walls of the tubes. Inside the shell two or more baffles are formed and arranged perpendicularly with respect to the centre axis of the shell. Between each baffle and the inner walls of the shell there is defined a corresponding window constituted by the cross-section for the passage of the second fluid, with a crossing direction parallel with the centre axis of the shell and the tubes, delimited by the free edge of the respective baffle on the one side and by the inner profile of the shell, at the intersection of the shell with the plane of the baffle, on the other side. The cross-section for the passage of the second fluid placed between two adjacent baffles is constant and has a rectangular shape, that is to say, with all the inner angles congruent with each other. Each baffle has a rectangular shape. Each window has a rectangular shape and has no tubes therein.

A heat exchanger assembly includes a manifold having a first side plate, a second side plate disposed opposite the first side plate, a first face plate, a second face plate disposed opposite the first face plate, a base plate, and a plurality of cooling elements. The first face plate and the second face plate each extend between the first side plate, the second side plate, and the base plate. The base plate extends between proximal ends of the first side plate, the second side plate, the first face plate, and the second face plate. The plurality of cooling elements extends between the first face plate and the second face plate.

A stacked-plate heat exchanger may include a high-temperature (HT) coolant circuit, a low-temperature (NT) coolant circuit, heat exchanger plates stacked upon one another and through which two coolants and a medium to be cooled may flow, and an obstruction configured to force a deflection of one of the coolants in the low-temperature coolant circuit. The two coolants may have different temperature levels in the high-temperature and low-temperature coolant circuits. The heat exchanger plates may include a partition wall separating the high-temperature and low-temperature coolant circuits from each other. The high-temperature and low-temperature coolant circuits may include a central HT coolant inlet and a central NT coolant outlet, respectively, adjacent to the partition wall and together forming a teardrop shape separated by the partition wall. The HT coolant inlet may have a part-circle-like shape and the NT coolant outlet may have a triangular shape, each having one side formed by the partition wall.

A machine for making liquid or semi-liquid products, including a first container adapted to contain a basic mixture, having an inside surface and an outside surface and equipped with a stirrer disposed inside the first container; a thermodynamic system comprising a circuit for circulating a heat exchanger fluid and a first heat exchanger associated, in use, with walls of the first container, the first heat exchanger is defined by at least one element which is fixable, in use, to the outside surface of the first container, having an open cavity, extending uninterruptedly and defining, when coupled with the outside surface, a channel for circulating heat exchanger fluid, the element also having at least one inlet and one outlet for the heat exchanger fluid.