6 replies to this topic

[danial.kamran]

Dear All,

 

I need help regarding calculation of mass of condensate and oil stored in tanks (fixed roof atmospheric tanks). A coriolis meter has been installed on experimental basis for measurement of production and dispatch on mass basis. Now daily mass recorded on totalizer is available but how to calculate mass of oil stock already stored in tanks? Which temperature is to be used and how to calculate SG of stock in tanks? Also volume shifted to tanks from other sources or decanted back also need to be evaluated on mass basis. LIT is available on tanks for level measurement and manual dip value confirms water cut. I am searching if some guidelines or standard method for calculation is available. 

[Bobby Strain]

There are some API procedures and software that fully cover what you are interested in. And, strapping tables for your tanks should be available within your organization.

 

Bobby

[Zauberberg]

See also http://www.emerson.c...tion/175314.pdf

 

and http://www2.emersonp...05-100-1034.pdf

Edited by Zauberberg, 28 September 2017 - 02:14 PM.

[danial.kamran]

Thank you all for helpful guidance. I am also looking for standard method for liquid hydrocarbon carbon daily production and stock calculation using meters and tank Levels? How standard conditions stock and production is calculated?

[ADITYA.DUBEY]

Thank you all for helpful guidance. I am also looking for standard method for liquid hydrocarbon carbon daily production and stock calculation using meters and tank Levels? How standard conditions stock and production is calculated?

 

For 24 hrs oil stock calculation -

 

A) Get the previous day Tank level height .(Suppose at 0600 hrs) and today's tank level height(at 0600 hrs)

 

B )Get the volume in m3 from the tank calibration chart with the help of level height.(There is a vendor/manufacturer calibration chart for every tank.Usually calibrated by third party vendors also.)

 

C) Now note down previous day and today's Tank material temp and density.

 

D) calculate Tank volume for both days in SCM (standard condition stock) with the help of vcf.(volume correction factor)

 

Volume in scm = volume (m3) * VCF

 

VCF = Exp(-(613.97226 / (density * density)) * (temp - 15) * (1 + (0.8 * (613.97226 / (density * density)) * (temp - 15))))

 

where density is in Kg/m3 and temp is in °C.

 

E) Now take the difference of these two day's reading of 0600 hrs. That is your 24 hrs day production.

 

Let me know if there is any more explanation required.

 

Note- For VCF calculation formula,you can refer other standards ,applicable in your company/country.

 

Regards

Aditya

Edited by ADITYA.DUBEY, 18 October 2017 - 11:26 AM.

[danial.kamran]

Aditya many thanks for such a detailed answer. One question that by tank material temperature you mean average temp. through out liquid level or point temperature.  

[ADITYA.DUBEY]

Average temp. commonly known as TMB(top ,middle,bottom) sample's density average and temp. average you have to consider.

 

Regards

Aditya