6. Steam Distillation :
The property of an immiscible liquid mixture
forms the basis of steam distillation.
Case 1 – Substance A is immiscible with water and
feed contains A and some traces of non volatile
impurities .
If system is not at equilibrium than
E – Vaporizing
efficiency
Case 2 – The feed is a mixture of A and C ; C is an essentially non volatile
substance, A and C form an ideal solution and are immiscible with water.
;
15. Advantages of RD :
1. Single column replaces one reactor and 3 distillation
columns which is process integration.
2. Less material is required for the construction of just single
column hence RD is much more cheap. Statistically, RD
reduces about 50% of the cost as compared to conventional
process.
3. Low energy consumption.
4. Lower operating cost .
Disadvantages of RD :
1. Degree of freedom is 3 for RD but for conventional process
it is 9. Hence conventional process gives us more variables
than RD.
2. Above mentioned volatility problem is also a disadvantage.
It limits it to very few reactions.
3. In some processes the optimum conditions of temperature
and pressure for distillation may be far from optimal for
reaction and vice versa.
16. Conclusion:
There are many methods to separate
various mixtures . Maximizing the
product by using minimum amount of
investment is our final aim.