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19 Cards in this Set
- Front
- Back
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Can crude oil be characterized by a chemical formula? |
No because it consists of many thousand different molecules |
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What does API stand for? |
American Petroleum Institute |
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API Gravity |
Density for oil. °API is a measure of how heavy or light the oil is compared to water. Specific Gravity |
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Sulphur Content (Crude oil properties) |
Generally classified as “sweet” crude or “sour” crude. Dissolved H2S can be hazardous when evolved |
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How do different weight percents of Sulphur effect crude oil |
0.5% > Crude is “sweet” crude 0.5% < Crude is “sour” crude 1% causes corrosion |
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Pour point (Crude Oil Properties) |
In Temperature, roughly indicates the relative paraffin and aromatic contents. Lower Pour Point = lower paraffin content and higher aromatic content
Higher Pour Point = higher paraffin content and lower aromatic content |
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Carbon Residue (Crude Oil Properties) |
Determined by distillation to a coke residue; indicates the tendency to form carbon deposits under high temperature conditions |
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Salt Content (Crude Oil Properties) |
NaCl content needs to be reduced to less than 1-10 pounds / thousand barrel to prevent corrosion. No universal standard and depends on location |
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Nitrogen Content (Crude Oil Properties) |
Causes poisoning of catalysts |
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Metal Contents (Crude Oil Properties) |
Nickel, vanadium, copper etc cause corrosion or poisoning of catalyst |
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How does number of carbons effect weight |
More carbon atoms makes for heavier oil components |
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What is the first step in refining Crude to consumer products? |
Atmospheric crude distillation Unit |
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What is the temp limit in an ACD unit and why? |
Approximately 400°C to avoid cracking and coking |
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What is the purpose for Vacuum distillation ? |
The heavy components from Atmospheric distillation residue can vaporize at a lower temperature due to the lower pressure |
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How are heavy oils or heavy residues upgraded to lighter oil fractions? |
Carbon Rejection Hydrogen Addition (hydroprocessing) |
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What are the two methods of Carbon Rejection |
Coking Solvent deasphalting |
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Coking |
When molecules are cracked into smaller ones at high temperature. There are insufficient hydrogen atoms to saturate the broken C-C bonds of the heaviest fraction with the lowest hydrogen to carbon ration. The cracked large molecules become petroleum coke |
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Solvent Deasphalting |
A solvent is used to extract the oil fraction, while the heaviest fraction becomes a solid |
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Hydrogen Addition |
Heavy oil is reacted with hydrogen at high temperature and pressure with a catalyst. Large molecules are cracked and broken bonds are saturated with hydrogen preventing coke formation |
