Allocation of Fluids in Shell-and-Tube Heat Exchangers

4 ALLOCATION OF FLUIDS IN SHELL-AND-TUBE HEAT EXCHANGERS 

In a new design, the allocation of streams to the tube-side or shell-side will be unknown at this stage. The issues to be considered for the allocation include  

These general guidelines can contradict each other. If this is the case, some compromise must be made. 

Example 15.2 A crude oil stream is to be preheated by recovering heat from a kerosene product in a shell-and-tube heat exchanger. The flowrates, temperatures and physical properties (at the mean temperatures) are given in Table 15.5. 

The exchanger type to be used is 1 shell-pass, 2 tube-passes. Because crude oil will have a greater tendency to foul than kerosene, crude oil will be allocated to the tube-side. Assume the fouling coefficient for kerosene on the shell-side is 5000 W m 2 K 1 and for the crude oil on the tube-side is 2000 W m 2 K 1. 

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