Cascade of Separation Stages

We have seen that a single equilibrium stage can only achieve a limited amount of separation. To extend the amount of separation we can make a cascade of stages, as shown in Figure 5. It is assumed in the cascade that streams leaving each stage are in equilibrium. Using a cascade of stages in this way allows the more volatile components to be transferred to the vapour phase, the less volatile components to be transferred to the liquid phase and a greater degree of separation to be achieved than for a single stage.

Figure 6 shows the liquid and vapour flows connecting the stages in a countercurrent cascade. As before, we assume constant molar overflow:

We can write an overall mass balance for component i across the cascade:

We can also write a mass balance around the envelope shown in Figure 6 over m stages:

LcX0,i + Vm + + 1,i = LmXm,i # Vtf ^ [17] This equation can be rearranged to give:

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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