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This is a course design assignment for the Principles of Chemical Engineering course. It’s my first time working on something like this, and I don’t quite understand it. I hope those who are more experienced can offer me some guidance. I. Topic: Selection of shell-and-tube heat exchangers II. Process requirements: It is necessary to cool a certain liquid organic substance with a temperature of 78 degrees Celsius down to 60 degrees Celsius. The flow rate of this organic substance is 29 Kg/s. Cold water at a temperature of t1 = 29 degrees Celsius is intended to be used for cooling, and it is required that the pressure drop on both sides of the heat exchanger tubes not exceed 0.1 MPa. The physical property data of the organic compound at 69 degrees Celsius are as follows: ρ=997 Kg/m3, λ=0.16 W/m·K, Cp=2.22 KJ/Kg·K, μ=0.6 mPa·s. III. Process: The pipeline layout is as shown in the figure. It is given that the pipe length at the pump inlet is L_in = 5 m, and the pipe length at the pump outlet is L_out = 15 m (both values do not include losses due to local resistance). It’s not easy to draw; there’s a heat exchanger above and a centrifugal pump below, connected by pipes. IV. Requirements: 1. Select a suitable heat exchanger ; 2. Arrange pipelines reasonably ; 3. Select a suitable centrifugal pump. What should the outlet temperature of the cooling water be set at? I also welcome all the more experienced colleagues to share their experiences and suggestions. It’s my first time working on design, and I’m quite nervous; I want to do a good job. Thank you!
The outlet temperature of the cooling water is 35 degrees. The model is BEM400-0.6-63-4/19-1I. The flow rates of the two pumps are 120 m³ and 180 m³ respectively. The head required can be determined based on the pressure drop in the piping and heat exchangers; the pressure drop on the process side is 35 KPa, while it is 15 KPa on the water side.