Modelling of HPRT in HYSYS

[chengg29]

Hi,

I am trying to model a Hydraulic Power Recovery Turbine (HPRT) in a Steady State simulation on HYSYS. As far as I can think I have two options to do it:

a) Use a PUMP module. When the simulation converges the Pump icon is outlined with a yellow line around the pump icon with a warning "negative head". However the corresponding value of the shaft power appears to be OK ignoring the negative sign prefixed to it

b) Use an EXPANDER module. When the simulation converges, the Expander icon is outlined with a yellow line with a warning "liquid in inlet stream". I guess it is becuase an Expander on HYSYS is meant only for vapour / gas. However the corresponding simulated value of power appears to be OK

Is any one of the above approaches is appropriate to model a HPRT or is there any thing wrong in the the above approaches towards modellin a HPRT on HYSYS? If so then what would be an appropriate method to simulate a HPRT?

Thanks in advance

cheers

 

[chemlite]

if you have only liquid with similar densities an (equivalent) pump model (considering dH) should give reasonable values,
if you wish to model change of phase, dV etc. a compressor ( expander ) model is more appropriate,
for those cases I have a specific model in PRODE PROPERTIES (compressor & expander with vapor + liquid),
may be you have something similar to select.

 

[chengg29]

Thanks Chemlite for the response. However the requirement is to work on HYSYS only for this project.

 

[chemlite]

the answer is generic about pump model available in most simulators (as for expander model)
since this is a chemical process engineering forum with contributes of CHEMCAD, PROII, VMGsim, Prode etc. users, you may expect responses from users of different software,
if you wish to limit responses there is a specific group devoted to aspen products.