4 replies to this topic

[wangdee.s]

Dear engineers,

 

I am trying to model a cold heat recovery system for LNG regasification using an ORC (cryogenic power generation). 

 

after searching for some process parameters, I found on a vendor's website (Exergy ORC systems for cold energy recovery in LNG) that LNG is pumped from its storage to around 70 to 80 bars (which is above its critical pressure) at -160C before absorbing heat and being let down to around 10 bars and 0C.

 

My question is: Is the heat recovery exchanger being operated in the supercritical region of natural gas? 

 

 

[breizh]

Hi,

Why don't you drop them an email?

They may answer your query.

Good luck.

Breizh 

[latexman]

Not my wheelhouse, but I'd guess it is operated in the supercritical region (above critical temperature AND pressure).  The P&ID I'm visualizing is a heat exchanger followed by a pressure letdown station.  My premise is the pressure drop in the heat exchanger will not be so great and the pressure stays above critical while the temperature is raised above critical.

 

If you find out, please let us know,

[breizh]

Hi,

https://www.scienced...36054422202326X

 

Doing some research (google), I found some information (above). It seems likely to be "supercritical".

Many more articles are available on the subject.

Breizh

[wangdee.s]

Dear engineers,

 

Hi,

https://www.scienced...36054422202326X

 

Doing some research (google), I found some information (above). It seems likely to be "supercritical".

Many more articles are available on the subject.

Breizh

 

Not my wheelhouse, but I'd guess it is operated in the supercritical region (above critical temperature AND pressure).  The P&ID I'm visualizing is a heat exchanger followed by a pressure letdown station.  My premise is the pressure drop in the heat exchanger will not be so great and the pressure stays above critical while the temperature is raised above critical.

 

If you find out, please let us know,

 

 

 

Thank you for the guidance (Mr. Breizh and Mr. Latexman). After reading your answers and confirming with further research/simulation, I would also say it reaches the super critical phase (say 60 bar and 0 degC) according to the methane phase diagram (simulation results were also showing zero latent heat of vaporization)