2 replies to this topic

[digeca]

Dear all,

I require to make a thermal precalculus for a Semirefrigerated Propylene vaporizer (Bayonet type) in order to send to supplier to obtain a cost + / - 10% . Is required to vaporize a portion of propylene (6000 Kg / H) contained in a sphere at 0 C and is required to vaporize till a minimum temperature of 2 C. I have calculated a vaporizer about 645.8 KW (2.3 GJ / h) The heating medium will be media pressure steam @ 9.5 Kg / cm 2 g. The process side design conditions are Pd = 20.9 Kg/cm2 / full vacuum and Td = 66 / -48 C (sphere design conditions). I would like to know more detail about what kind of tube should be use (minimum diameter), pipe and shell material, tube arrangement. Somebody could inform me about the literature that I can use to prepare the data sheet specification of this vaporizer.

From the point of view of control I´m proposing a cascade control where primary controller PIC will be responsible for maintaining constant the outlet pressure. The output of this controller is the setpoint of the secondary controller LIC whose mission is to control the opening of the control valve that will be installed at the inlet to the evaporator. What level should control? this is related to the thermal calculation? If anyone has experience in this type of system I would appreciate your comments

Thanks in advance

[srfish]

As you may have found out, this type of heat exchanger is seldom used anymore. Information can be found in "Process Heat Transfer by Donald Q. Kern. That was published in 1950 by McGraw-Hill. There is a small amount of information in the Heat Exchanger Design Handbook.

[digeca]

Thanks Srfish,

I know that this type of heat exchanger is seldom used anymore, however our client request it. I'll take a look at this Book.