evaporator is a refrigerant four pieces of a very important part of the condensed liquid by cryogenic evaporator exchanges heat with the outside air, endothermic gasification, to achieve the cooling effect. After
1. Evaporator description
Central tube evaporator circulation
The steam generated in the heating chamber with a large number of liquid foam, into the evaporation chamber of a large space, these liquids by in addition to their role of coagulation or the like to foam separated from the vapor. Mo is generally provided in addition to the top of the evaporation chamber.
evaporator operating pressure divided by atmospheric pressure, 3 kinds of pressurization and depressurization. Solution by physical exercise condition evaporator points are: ① cyclic. Boiling solution a plurality of times in the heating chamber by heating the surface, such as a central circulating tube, suspended basket type, external heating, Levin and forced circulation type and the like. ② one-way type. Boiling solution in the heating chamber by a heating surface, without circulation, i.e. the line for discharging concentrate, such as a rising film, falling film, stirred and centrifugal thin film type. ③ direct contact type. Heating the solution in direct contact with the heat transfer medium, such as a submerged combustion evaporator. Evaporation apparatus during operation, the heating consumes a lot of steam, in order to save heating steam, multi-effect evaporation may be employedMeans and vapor recompression evaporators. Evaporator is widely used in chemical industry, light industry and other sectors.
Medical use an evaporator vaporizer, inhalation anesthetics showed the volatile liquid at room temperature. Evaporator effective to vaporize a volatile liquid anesthetic gas, and to accurately adjust the concentration of anesthetic vapor output. Anesthetics evaporator requires heat, the temperature around the evaporator is a major factor in determining the rate of evaporation of volatile anesthetics. Modern anesthesia machine flow extensive use of a temperature compensation type evaporator, i.e., when the temperature changes or the fresh gas flow, by automatic compensation mechanism to keep constant evaporation rate of the volatile inhalation anesthetics, thereby ensuring inhalation anesthetics exiting the evaporator the output density stable. Due to the different physical characteristics of the boiling point and saturated vapor pressure of volatile inhalation anesthetics such as different, and therefore, drugs having a dedicated evaporator, an evaporator such as enflurane, isoflurane evaporator or the like, each can not be universal. Modern anesthesia machine vaporizer anesthetic breathing plurality placed outside the loop, there is connected thereto a separate oxygen flow, the inhaled anesthetic evaporated vapor is mixed with the main gas stream for inhalation by a patient before.
2. Evaporator Category
1. By partial evaporation:
natural evaporation: the solution is evaporated below the boiling temperature, such as sea salt production, in this case, because only a low solvent was vaporized in the surface of the solution, the solvent vaporization rate.
boiling off: The solution was heated to boiling point, so that evaporated under boiling state. INDUSTRIAL evaporation operation are all substantially such.
2. Heating points by:
a direct heat source which is to mix the fuel with air, so that temperature of flame and smoke generated by the combustion of jetInjected directly into the mouth the solution was evaporated to heat the solution, the solvent vaporized during the evaporation.
Indirect heat source for heating the container to pass partition was evaporated. Namely in the recuperative heat transfer of heat exchanger.
3. Operating pressure divided by:
can be divided into ordinary pressure, pressurization and reduced pressure (vacuum) evaporation operation. Obviously, for heat-sensitive materials, such as antibiotic solution, fruit juice should be carried out under reduced pressure. While high viscosity materials should be pressurized high temperature heat source (e.g. heat transfer oil, molten salt, etc.) and evaporated
4. Divided by the number of effect:
can be divided into single and multi-effect evaporation efficiency. If the secondary steam condensate direct evaporation no longer use, known as single-effect evaporator. If steam is used as a next secondary effect heating steam, and a plurality of evaporators connected in series, the evaporation process is the multi-effect evaporation.