11 replies to this topic

[sajju]

hello everyone

 

i am a fresh Graduate chemical engineer. At present i am working in a oilfield equipment manufacturing company. here we manly concentrate on 3-phase separators, indirect water bath heater, frac tanks, surge tanks...

 

after i am joining to this company our process engineer (earlier person) resigned. now the problem is here no one to help me regarding the process design calculations.Unfortunately  we do not have any files regarding the design calculation or no one aware of that.  i have completed 15days in this company but still i can not understand the design calculation and formula and all.

 

Now my manager is asking me the process design calculations for the surge tank including inlet, outlet nozzle location and all. as per p&id i have it shows data as  follows

capacity     =50bbl

pressure    =50psi

 

please reply back to me as soon as possible with the design calculations (formula) what ever u have for the equipment i have mentioned above or give me the example calculation for all if possible.

 

thank you

 

 

 

[jrtailor09]

Dear ashrath,

 

Surge tank shallbe designed considering the following hold up time for both horizontal as well as vertical vessel.

 

regards,

 

 

 

-Unit feed surge drum, upstream unit in same control room : 15 minutes

-Unit feed surge drum, upstream unit in separate control room : 15

minutes

[sajju]

Dear ashrath,

 

Surge tank shallbe designed considering the following hold up time for both horizontal as well as vertical vessel.

 

regards,

 

 

 

-Unit feed surge drum, upstream unit in same control room : 15 minutes

-Unit feed surge drum, upstream unit in separate control room : 15

minutes

 

 

Mr. jrtailor

 

thanks for your reply but i would like to know is that a standard residence time or by experience u are saying. and also i want the inlet & outlet nozzle location and all the surge tank calculations.

 

kindly provide me the other design calc for the other equipments as i mentioned above if possible.

 

thank you

[Bobby Strain]

Does some else cook your meals? You need to spend some time looking for your answers. You will learn a lot more if you do.

 

Bobby

[Anshul619]

For surge drum Plz refer to Shell DEP 31.22.05.12

 

I think you will find more info for calculations in this book..

 

Regards

Anshul

[sajju]

For surge drum Plz refer to Shell DEP 31.22.05.12

 

I think you will find more info for calculations in this book..

 

Regards

Anshul

dear anshul

 

can you please upload Shell DEP 31.22.05.12 if u have??

[markymaark]

"Standard" residence time is dependent on the project, industry, material etc.  It really is more of an experience question that relates safety, operability and economics.Ask yourself, is 1 hour good?  How large will that tank be?  Why does it need to be so large?  Then go smaller, or go larger.  Engineers don't go by "standard" for every single project.  There's codes, which are for safety and GMP, but overall we design based on logic.

 

Don't ask "is 15 minutes standard".  Instead, look at what 15 minutes will do for your tank size.

 

In regards to your nozzle size.  I'd say its more dependent on your outlet pipe size.  That depends on flowrates and acceptable pressure drops and velocities.  Those you will find in CRANE's TP.

 

Don't feel overwhelmed.  You are new.  These struggles are expected.  In 3 months, you'll look back and realize you can do this problem in 10minutes instead of 20 days.  It's a big learning curve, but don't feel overwhelmed.

[sajju]

"Standard" residence time is dependent on the project, industry, material etc.  It really is more of an experience question that relates safety, operability and economics.Ask yourself, is 1 hour good?  How large will that tank be?  Why does it need to be so large?  Then go smaller, or go larger.  Engineers don't go by "standard" for every single project.  There's codes, which are for safety and GMP, but overall we design based on logic.

 

Don't ask "is 15 minutes standard".  Instead, look at what 15 minutes will do for your tank size.

 

In regards to your nozzle size.  I'd say its more dependent on your outlet pipe size.  That depends on flowrates and acceptable pressure drops and velocities.  Those you will find in CRANE's TP.

 

Don't feel overwhelmed.  You are new.  These struggles are expected.  In 3 months, you'll look back and realize you can do this problem in 10minutes instead of 20 days.  It's a big learning curve, but don't feel overwhelmed.

 

 

Thanks for your favorable reply. can you please upload CRANE's TP which you mentioned if possible.

 

thank you

[markymaark]

This site is very cautious on uploading copyrighted material.  This Crane TP is a standard in our industry and is very cheap for a lifelong reference.

[Anshul619]

This site is very cautious on uploading copyrighted material.  This Crane TP is a standard in our industry and is very cheap for a lifelong reference.

 

Yep, I uploaded a shell DEP but it was deleted from the site.

[sajju]

can any one suggest how to locate the inlet and outlet nozzle location, is there any calculations are there?

 

referring to  previous project i have given the same location but out client doesn't want that he want inlet pipe location some what lower to the what i specified.

 

kindly suggest if i go with the client then is there any changes will take place in holdup vol, hold up time, flow rate or any other parameters will disturb ??

 

surge tank details

vertical tank- 50bbl

ID=2231mm

T/T length= 1400

inlet pipe = 3inch NB

pressure= 50psi

Inlet pipe location from the bottom of the tank= 1248 mm (client want this at 1100 mm)

 

if possible attach the total process design calculations involved in surge tank. 

[kem23]

Please what is the API RP for sizing a surge vessel