Heat pumps driven distillation

Figure 11.14 Column profiles help to develop complex distillation set-up 11.2.2 Heat pumps driven systems...

Membrane distillation offers a number of advantages over alternative pressure-driven processes such as reverse osmosis. Because the process is driven by temperature gradients, low-grade waste heat can be used and expensive high-pressure pumps are not required. Membrane fluxes are comparable to reverse osmosis fluxes, so membrane areas are not excessive. Finally, the process is still effective with slightly reduced fluxes even for very concentrated solutions. This is an advantage over reverse osmosis, in which the feed solution osmotic pressure places a practical limit on the concentration of a salt in the feed solution to be processed. 

Before fractional distillation, petroleum is refined by a pre-distillation method so that undesired oomponents are driven out of the petroleum mixture. After that, the petroleum is pumped through heated pipes at 350-400° C. Here, the petroleum becomes vapor and this is sent to the fractional distillation unit The petroleum vapor starts rising to the upper parts of the fractional distillation unit. The vapor of petroleum cools down at lower temperatures the uppermost part of the distillation unit is the place for gases (methane, ethane, propane and butane), which have boiling points lower than 2QPC C Hg and C H.jq are separated from each other at high pressures and stored in canisters for home use. crude oil... 

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