Design of Heat Exchanger using ASPEN Shell & Tube Exchanger

 example:

Design an exchanger to sub-cool condensate from a methanol condenser from 95°C to

40°C. Flow-rate of methanol 100,000 kg/h. Cooling water will be used as the coolant,

with a temperature rise from 25°C to 40°C.

1.

Determine the heat exchanger duty

In this example, since coolant is more corrosive, it is assigned to the tube side.

Specific heat capacity of methanol = 3.926kJ/kg°C

Heat Exchanger Duty

Q = mCp.(AT) =(100000/3600) × 3926 × (95 – 40) =

 5998.056 × 10³W = 5998.056kW

2.

Specific heat capacity of water[= 4.2kJ/kg°C

Mass flowrate of cooling water:

mwater= Q/Cp.water (Twater out-Twater.in)= (5998056/4200(40-25))= kg/S 95.21 = 342360 kg/hr

Using 1-2 Shell and Tube Heat Exchanger,

Log Mean Temperature Difference:

see simulation