7 replies to this topic

[Guaiamum]

Dear Friends!

 

I have a 15000 m³ "API 650 Tank", and I must choice a  "Flame Arrester" for it. The product is an heavy fuel oil, and the maximum temperature inside the tank is 80 ºC.

 

By API 2000 (2014), the vapor being displaced in outbreathing shall be converted to an equivalent flow of air at normal or standard conditions, because the tank is operating above 120 ºF (49 ºC). And for doing so, I must know the molecular weight of that vapor in the actual conditions of pressure (1,85 inch/water column), and temperature (80 ºC), to enter the API formula.

 

My question is : how can I obtain such value?! It seems impossible to me to find the necessary data, but maybe someone will be so kind and teach me how to "solve this mistery"!!

 

Best Regards

 

Guaiamum

[christopherchoa]

This mystery is not mystery at all.

 

 

Use air if there is no blanketing, or use blanketing gas molecular weight. It does not change with pressure and temperature.

 

 

If you have the latest version (7th Ed) of API 2000, go to Table D.1 (see comments). Air is used for less than 49degC. It is implied to use air for greater than 49 degC if you truly have no blanketing gas for the tank.

 

 

Don't forget to include both thermal and normal for your flame arrester.

[Guaiamum]

Dear christopherchoa

 

Thank you for your answer.

 

However, from Table D.1, and for outbreathing (free vent), I understood that air is only permitted if the tank temperature is less than 49 ºC. If it is greater than that, then threre will be a mixture of air and vapor of the tank contents ("fuel vapors", in this case), that we shall take into account.

 

And that is my "problem" : how can I find the properties of that vapors? Namely specif weight, and molecular weight, to enter the formula D.37, to convert to an air-equivalent flow at normal or standard conditions?

 

I am saying anything stupid?

 

Thanks for the help.

 

Best Regards

 

Guaiamum

[christopherchoa]

Guaiaman,

 

I think you are right and I am wrong. hehe. Your interpretation is logical.

 

Let me get back to you as I look more into the standard next week.

[Guaiamum]

Dear Christopherchoa

 

Thank you again for your help and time.

 

Best Regards

 

 

 

 

 

 

[Usama Khan]

Dear Friends

 

My question is :  How can we calculate the size of Vapor equalizer line and Vent line in LPG system?

 

please guide me.

 

Thanks

[christopherchoa]

Hi Guaiaman,

 

Can you use Equation D.36, D.37 (API 2000 2014 Edition)? Simplified conversion equations

 

How did you resolve this problem?

 

Regards,

Christopher

[ana ibarra]

estimados, alguien me puede pasar el archivo PDF del API 2000 7a. edición

 

Saludos.