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看看下面这段话的介绍吧!
Processing mode refers to the way in which feed and product are introduced and withdrawn from the process. Distillation occurs in two modes, continuous distillation and batch distillation.
Continuous distillation is feed is sent to the still all the time and product is drawn out at the same time. The idea in continuous distillation is that the amount going into the still and the amount leaving the still should always equal each other at any given point in time.
Batch distillation is when the amount going into the still and the amount going out of the still is not supposed to be the same all the time. The easiest example to use is like old fashioned spirit making. The distiller fills a container at the start, then heats it, as time goes by the vapors are condensed to make the alcoholic drink. When the proper quantity of overhead (drink) is made, the distiller stops the still and empties it out ready for a new batch. This is only a simple case, in industrial usage what goes on gets very complex.
Both continuous and batch distillation are very important to industry. Continuous distillation is most often used with big volume products like jet fuel, benzene, plastic monomers. Batch distillation is most often used with smaller volume products and in plants that make lots of different things and use the same still for many products (in different batches).
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