Different Grades of Oil

We’ve received many emails from clients asking about the different grades of oil, we are not specialist oil traders however we know a man who is. So I’ll answer your questions in this blog. Crude varies depending on sulfur content. The more expensive crudes are low sulfur sweet light crudes which are easiest to refine, the least expensive crudes have a higher sulfur content and referred to as sour heavy crudes. Sour crudes have a content of more 1.5% of its weight in sulfur while sweet light crudes have a sulfur content of less 0.5%. Sulfur reduces the energy content of crude by displacing hydrocarbon molecules. Sulfur can also damage refining equipment and it’s a terrible pollutant. This is why most refiners want to pay the higher price for sweet light crudes.

Crudes are measured by different methods the most common is the API Gravity measurement where 10 is the API gravity for water.  0 is the reading for the heaviest crudes and 100 the lightest. The majority of refiners look for crudes with an API Gravity of 30-40. The Tapis blend form Malaysia is the most expensive crude it has the highest gravity and lowest sulfur. The least expensive crudes are Bow River from Alberta and Maya from Mexico, these crudes have API’s from 16-36 and sulfur content from 2.4 – 3.3%. These crudes are not the best to refine and refiners usually only purchase them after a discount.