MVR是机械式蒸汽再压缩技术（mechanical vapor recompression ）的简称，是利用蒸发系统自身 产 生的二次蒸汽及其能量，将低品位的蒸汽经压缩机的机械做功提升为高品位的蒸汽热源。如此循 环 向蒸发系统提供热能，从而减少对外界能源的需求的一项节能技术。除开车启动外，整个蒸发过 程 中无需生蒸汽。

多效蒸发：在蒸发生产中，二次蒸气的产量较大，且含大量的潜热，故应将其回收加以利用，若将 二次蒸气通入另一蒸发器的加热室，只要后者的操作压强和溶液沸点低于原蒸发器中的操作压强和 沸点，则通入的二次蒸气仍能起到加热作用，这种操作方式即为多效蒸发。

多效蒸发中的每一个蒸发器称为一效。凡通入加热蒸汽的蒸发器称为有效，用有效的二次蒸气 作为加热剂的蒸发器称为第二效，依此类推。采用机械式蒸汽再压缩技术多效蒸发器的目的是为了节省加热蒸气的消耗量。

MVR is the abbreviation of mechanical vapor recompression technology (mechanical vapor recompression), which uses the secondary steam and energy generated by the evaporation system itself to upgrade low-grade steam through the mechanical work of the compressor to a high-grade steam heat source. It is an energy-saving technology that provides heat energy to the evaporation system in such a cycle, thereby reducing the demand for external energy. There is no need to generate steam during the entire evaporation process except for the start-up.

Multi-effect evaporation: In evaporation production, the output of secondary steam is large and contains a lot of latent heat, so it should be recycled and used. If the secondary steam is passed into the heating chamber of another evaporator, as long as the latter’s The operating pressure and the boiling point of the solution are lower than the operating pressure and boiling point in the original evaporator, and the secondary steam introduced can still play a heating role. This operation mode is multi-effect evaporation.

Each evaporator in multi-effect evaporation is called an effect. The evaporator with heating steam is called effective, and the evaporator with effective secondary steam as the heating agent is called the second effect, and so on. The purpose of adopting the mechanical vapor recompression technology multi-effect evaporator is to save the consumption of heating steam.