Further Discussion of Specific Issues

The Energy Balance and the Assumption of Constant Molar Flows

All the calculations in this article are based on the assumption of constant molar flows in a section, i.e. Vn = Vn — 1 = V and Ln = Ln + 1 = L. This is a very common simplification in distillation computations, and we shall use the energy balance to see when we can justify it. The energy balance is similar to the

Figure 9 Regions of distributing feed components as a function of V and D for a feed mixture with three components: ABC. Pj represents minimum energy for sharp split between components / and j For large vapour flow (above the top sawtooth), only one component distributes. In the triangle below Pac, all components distribute.

Figure 9 Regions of distributing feed components as a function of V and D for a feed mixture with three components: ABC. Pj represents minimum energy for sharp split between components / and j For large vapour flow (above the top sawtooth), only one component distributes. In the triangle below Pac, all components distribute.

mass balance, but now we use the molar enthalpy (h) of the streams instead of composition. The enthalpy is computed for the actual mixture and will be a function of composition in addition to temperature (or pressure). At steady state the energy balance around stage n becomes:

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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