Application of heat exchangers in the pharmaceutical industry
A heat exchange device is a device that performs various heat exchanges and is commonly referred to as a heat exchanger or simply a heat exchanger. The working principle of the heat exchange device is that the hot fluid and the cold fluid simultaneously flow on both sides of the heat transfer surface of the heat exchanger, and heat is transferred from the hot fluid to the cold fluid through the wall surface. There are three basic ways of heat transfer, namely heat transfer, heat convection and heat radiation.
In pharmaceutical production, many processes are related to heat transfer. For example, many chemical reactions such as sulfonation, nitration, halogenation, condensation, etc. in the production of pharmaceuticals need to be carried out at a suitable temperature in accordance with the desired reaction direction, and reduce or avoid undesirable side reactions; In the jacket or coil, steam or cold water is introduced to carry out heat input or take-out; various operations such as evaporation, crystallization, drying, distillation, freezing, etc. are also performed on the purification or purification of the raw materials after the raw materials are purified. The input or removal of heat is not required; in addition, the heating pots, equipment and various pipes in production are often covered with a heat insulating layer to prevent heat loss or introduction, and are also heat transfer problems.
The heat exchange equipment commonly used in the production of the pharmaceutical industry is a partition wall heat exchanger, which can be divided into a shell-and-tube heat exchanger and a plate heat exchanger according to the shape of the heat exchange surface. Generally, plate heat exchangers have a heat transfer area per unit volume and a heat transfer coefficient much larger than tubular heat exchangers, so they are also called high-efficiency heat exchangers.
Heat exchangers have a variety of situations and structures due to different conditions of use. The heat exchange equipment can be classified into a heater, a cooler, a condenser, and a reboiler, depending on the purpose of heat exchange. According to the different heat transfer methods of cold and hot fluids, it can be divided into direct contact heat exchangers, that is, hybrid heat exchangers, direct contact heat between hot and cold fluids, partition wall heat exchangers and regenerative heat exchangers.