Columns balancing

Control analysi.s/design. Analysis of column balances and profiles to aid in control system design and operation. 

A concave meniscus occurs in a liquid in which the adhesive forces are greater than the cohesive forces. The liquid climbs to a height where the weight of liquid column balances the attraction to the walls. 

With the overall column balance M = + A and the definition of the feed ratio u=M/E, the following applies for the balance line of the stripping section ... 

Chromatography. I. Packing of columns Balanced density slurry method was employed and the quality of packed columns was tested chromatographically in methylene chloride. Benzene was injected as testing solute. Columns which gave satisfactory results [l.e., symmetrical elution curve, relative band broadening of 50 ym at linear velocity of 5 mm/sec, and permeability better than 1.10 -9 cm 2] were used for further experiments. 

An enthalpy balance over the whole column (balance envelope I in Fig. 5.2-4) delivers the relationship... 

These six equations have six unknowns If, j+i, Xf, Hf+j, and hf. Xg is specified in the problem statement B and Qr were calculated from the column balances and yf (required for the last equation) was obtained from the solution of Eqs. r4-l. stage jl to t4-4c. stage jl with] = f - 1. At the feed stage we change from one set of balance envelopes to another. 

Figure 10-18. Column balancing methods for vapor feed with largest calculated diameter at the top.

Figure 10-19. Column balancing methods for liquid feed with largest calculated diameter at the bottom. (A) Heat entire feed. (B) Use two-enthalpy feed and heat portion of feed. (C) Vapor...

Using the notation given for cocurrent flow, a mass balance for the whole separation column (balance area I in Fig. 1-52) for the component to be transferred is... 

---