lamo
Mechanical
- Sep 4, 2019
- 3
Good day gentlemen,
I'm a bit baffled by the selection of temperature difference in the design of heating of continuous process reactor.
The reactor is a 10 m3 pressure vessel with an agitator and heating coil. The reactor will be continuously fed with two substances of 170 C and 20 C. The mixture inside the reactor will be heated to 220 C by 240 C thermal oil coils and jacket and will flow out through the bottom.
If no agitator was present I could use heat exchanger logic -> entering mixture is of 80 C, leaving 220 C; entering thermal oil is of 240 C, leaving 200 -> use the resulting LMTD of 55 C as temperature difference or gradient. Use the LMTD for sizing the coils.
But because of the agitator the flow won't be from top to bottom. And the operating principle should be - the whole reactor heats up to 220 C and then the temp is maintained. So neither counter-current nor co-current heat exchange can be assumed.
Has anybody have experience with such designs? How would you select the LMTD for coil sizing?
Thank you for your 2 cents
I'm a bit baffled by the selection of temperature difference in the design of heating of continuous process reactor.
The reactor is a 10 m3 pressure vessel with an agitator and heating coil. The reactor will be continuously fed with two substances of 170 C and 20 C. The mixture inside the reactor will be heated to 220 C by 240 C thermal oil coils and jacket and will flow out through the bottom.
If no agitator was present I could use heat exchanger logic -> entering mixture is of 80 C, leaving 220 C; entering thermal oil is of 240 C, leaving 200 -> use the resulting LMTD of 55 C as temperature difference or gradient. Use the LMTD for sizing the coils.
But because of the agitator the flow won't be from top to bottom. And the operating principle should be - the whole reactor heats up to 220 C and then the temp is maintained. So neither counter-current nor co-current heat exchange can be assumed.
Has anybody have experience with such designs? How would you select the LMTD for coil sizing?
Thank you for your 2 cents