The condenser is a component of the refrigeration system, which is a kind of heat exchanger, which can convert gas or vapor into liquid, and transfer the heat in the tube to the air near the tube in a fast manner. According to the different layouts of the internal heat exchange tubes, it can be divided into tubular condensers and spiral tube condensers.

The heat exchanger is a heat exchange device between two immiscible media. It consists of an outer cylinder with sealing plates at both ends-two support plates and many heat exchange tubes. The tube heat exchanger has a simple and compact structure, high heat transfer coefficient and good condensation effect when the structure design and operating conditions are reasonable, and it is suitable for the condensation and recovery of various solvent vapors.

Gas heat exchange requires a long heat exchange path, so this type of heat exchanger is designed as a long strip.

The tubes of the tube-and-tube heat exchanger can be ordinary carbon steel tubes, stainless steel tubes, aluminum tubes or copper tubes. The heat exchanger is exposed to water and organic impurities for a long time during the working process, and the tube is corroded seriously. The use of stainless steel tube can effectively prevent corrosion, the tube wall is not easy to scale, easy to clean, the heat transfer coefficient is higher, and the extension of the service life also makes up for the disadvantage of higher price. For condensers of the same area, the difference in tube material and cooling medium flow rate has a significant impact on the heat transfer coefficient.

The heat exchanger is a device that transfers part of the heat of the hot fluid to the cold fluid, also known as the heat exchanger. Heat exchanger occupies an important position in chemical, petroleum, power, food and many other industrial productions. In chemical production, heat exchangers can be used as heaters, coolers, condensers, evaporators and reboilers, etc., and are widely used .

In a floating head heat exchanger, only one end of the tube plates at both ends is fixed to the shell, and the other end can move freely relative to the shell, which is called a floating head. The floating head is composed of a floating tube plate, a hook ring and a floating head end cover, and is detachable connection, and the tube bundle can be drawn out from the shell. The thermal deformation of the tube bundle and the shell are not restricted to each other, so no thermal stress is generated. Its advantage is that it is easy to clean between and inside the tube without thermal stress; but its structure is complex, the cost is higher than that of a fixed tube-sheet heat exchanger, the equipment is heavy, the material consumption is large, and the small floating head end cover cannot be checked during operation. The sealing requirements are higher during manufacturing. It is suitable for occasions where the wall temperature difference between the shell and the tube bundle is large or the shell side medium is easy to scale.

Heat exchange reactors are also called non-adiabatic variable temperature reactors, and their structure is mostly similar to shell and tube heat exchangers. The catalyst can be placed in the tube or between the tubes, but the latter is less common. The gas of the heat exchange fixed-bed reactor flows down into the catalyst bed from the top of the reactor and flows out at the bottom. In actual production, most of them use a top-down flow method.