In the field, we’ve heard of purchasers using diesel oil and gasoline as solvents to calculate the BS&W level of a tank’s oil.
However, did you know that both diesel oil and gasoline carry trace amounts of water and add to the measured BS&W that is already in your oil?
Some gasolines contain as much as 0.3% water… add this to your sample, and you’ll “give away” 3 of every 1000 barrels that you produce.
Diesel, when used as a solvent, can be especially detrimental to the seller.
Diesel precipitates much of the asphaltenes and heavier hydrocarbons on contact. This means that the purchaser’s measurements will reflect a higher BS&W content than would be recorded with a more “operator friendly” solvent.
GreaseBook has been advised that the following solvents are best:
- stoodard solvent
- touluene, water saturated
- xylene, water saturated
- kerosine
- white gasoline
What does the Savvy Operator do if he doesn’t have any of the good stuff on hand (ie you’re stuck with diesel or gasoline)?
He measures the BS&W level of the solvent before applying it to his crude sample. Then, he simply subtracts the (newly determined) BS&W level of the solvent from the measured BS&W of the crude.
One last word of wisdom folks: when measuring an oil sample, make sure your purchaser uses a fresh/clean beaker.
A lot of purchasers use water to clean out a dirty beaker (and make the mistake of leaving a little bit of water at the bottom). Water has an API of 10, and when mixed with your sample, consequently lowers the measured API of your oil (which could spell a lower sales price for you).
Next installment of GreaseBook’s Savvy Operator: How to transform a rejected tank of crude into a saleable tank in under 30 seconds…