Results 1 to 6 of 6
  1. #1

    Adiabatic Depressuring using HYSYS

    I am using Depressuring utility from HYSYS to check time taken by blowdown valve to depressuring the inventories. There is RO before the blowdown valve and I can size a relief valve using RO size say 25 mm , 50 mm Orifice dia.

    My query .. if there is no RO in the piping and only blowdown valve .. shall I take full bore dia.. as RO in case I have 4 "pipe and 4 " blowdoen valve..

    Please help me..


    See More: Adiabatic Depressuring using HYSYS

  2. # ADS
    Spons Circuit
    Join Date
    Always
    Posts
    Many
     
  3. My friend, I dont understand the reference you made to a "relief valve", but regarding your question I suggest you to proceed as follows: if you dont have a RO downstream your blowdown valve (BDV), then the only restriction that limits the flow rate is such BDV. BDVs are normally ball valves, either regular (reduced) port or full port.
    To calculate the peak flow you need to know the Cv of your BDV, which can be obtained from vendors literature (be carefull: full port valves have a higher cv than regular port valves).
    Once you have the Cv of your BDV you may calculate the peak flow using the following equation (for critical flow conditions P2 < 0,53 x P1):
    q = 660 x Cv x P1 x sqrt (1/(SG x T1)), where q [=] SCFH, P1 [=] psia, T1 [=] &#186;R.
    After obtaining the peak flow rate through your BDV, go to Hysys and modify the orifice area in so as to obtain the same peak flow rate.
    In this way, the depressuring time calculated by Hysys will be reasonably realiable.
    Hope this helps.
    Good luck!
    Mart&#237;n

  4.    Sponsored Links



    -

  5. #3

  6. Re: Adiabatic Depressuring using HYSYS

    Also, in Hysys, you may also input valve CV and let it runs.

    My threads; raybk2000 :


  7. Re: Adiabatic Depressuring using HYSYS

    I am sorry Martinmas I don't understand.
    For Cv of the valve I must know the peak flow, so how may obtain the Cv without know peak flow rate?

  8.    Spons.


  9. Re: Adiabatic Depressuring using HYSYS

    I am sorry Martinmas I don't understand.
    For Cv of the valve I must know the peak flow, so how may obtain the Cv without know peak flow rate?

  •   

Similar Threads

  1. Depressuring In Hysys!
    By tungpt.rd in forum Oil And Gas Process
    Replies: 0
    Last Post: 10-14-2013, 06:12 AM
  2. Depressuring Query
    By Mohammad Hussain in forum Oil And Gas Process
    Replies: 0
    Last Post: 08-15-2013, 02:27 PM
  3. Depressuring Analysis
    By panos in forum Petroleum Refining
    Replies: 29
    Last Post: 08-13-2011, 06:10 AM
  4. Article: Adiabatic Depressuring using HYSYS
    By ayya in forum Home Articles
    Replies: 2
    Last Post: 05-02-2011, 01:08 PM
  5. Article: Adiabatic Depressuring using HYSYS
    By ayya in forum Home Articles
    Replies: 0
    Last Post: 04-16-2011, 11:35 PM

Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •