5 replies to this topic

[alchemist]

Hi,

 

I am trying to estimate the cost of MP steam (500 psig) for a technoeconomic analysis.

 

I have the cost of LP (65 psig) and HP (1645 psi) steam, all at saturated conditions.  I need to estimate the cost of the MP steam, but am having trouble doing so.

 

My initial thoughts were to normailze the costs by the enthalpy of the steam.  Turns out, beyond a certain pressure, the specific enthalpy of steam decreases.  In my case, the enthalpy of the 1645 psig steam is lower than the enthalpy of the 500 psig steam.  On that basis, the 500 psig steam would be more expensive than the 1645 psig steam, which does not make sense.

 

Any tips on how to estimate the cost of the MP steam.

 

Thanks

-AC

[Bobby Strain]

You should set the cost based on fuel for HP steam less extracted power value for lower pressure steam.

 

Bobby

[gegio1960]

why not a prorate of LPS and HPS costs based on pressure?

[Napo]

Dear Alchemist,

 

You can review the article: "How to Estimate Utility Cost", by Ulrich G. and Vasudevan P., Chemical engineering, Apr., 2006, p.66-69.

 

I hope help you.

 

Regards,

 

Napo.

[breizh]

As suggested by Napo ,

 

Another very good link.

https://www1.eere.en...f_true_cost.pdf

 

with a reference from the link  above : CHE September 1994.

 

Should help you and others.

 

 

Breizh

Edited by breizh, 06 April 2015 - 08:02 PM.

[Napo]

Alchemist,

 

Also you can review the following books:

 

- Ganapathy V., Nomograms for Steam generation and utilization, p. 33.
- Institut Francais du Petrole (Chauvel A., Leprince P. et. al.), Manual of Economic Analysis of Chemical Processes, p. 155.

 

Napo.