How to distinguish reaction principles

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The basic concepts of pressure vessels are described as follows: (1) Reaction pressure vessels (code R): These are pressure vessels primarily used to carry out physical and chemical reactions of substances, such as reactors, reaction kettles, decomposition pots, vulcanization tanks, decomposition towers, polymerization kettles, autoclaves, ultra-high pressure reactors, synthesis towers, shift furnaces, cooking pots, steam generators, autoclaves for autoclaving, and gas generators； (II) Heat exchange pressure vessels (code E): These are pressure vessels primarily used for facilitating heat exchange of fluids, such as shell-and-tube waste heat boilers, heat exchangers, coolers, condensers, evaporators, heaters, sterilization kettles, dyeing machines, drying cylinders, steaming and frying pots, preheating kettles, solvent preheaters, steam generators, and gas generator water jackets ； (III) Separation pressure vessels (code S): These are primarily pressure vessels used for achieving fluid pressure balance and buffering, as well as for the purification and separation of gases; examples include separators, filters, oil separators, buffers, washers, absorption towers, steel washing towers, drying towers, stripping towers, steam separators, and deaerators ； (IV) Storage pressure vessels (code C, with spherical tanks coded as B): These are primarily pressure vessels used for storing gases, liquids, liquefied gases, and other such substances, such as storage tanks of various types. In a pressure vessel that has two or more process flow paths simultaneously, the types are classified according to the primary function within the process.