Why do they describe OIL as SWEET, LIGHT, CRUDE?

I don't know anything about this, but I always hear this terminology when I listen to the market reports in the early morning.

If you know the answer, please post and make me smarter!

Many thanks.

light refers to its density (light = low density; heavy = high density).

Crude because it has not been refined.

http://news.bbc.co.uk/1/hi/business/904748.stm

"'Sweet' crude is defined as having a sulphur content of less than 0.5%.

Oil containing more than 0.5% sulphur by weight is said to be 'sour'."

Sweet crude (like from West Texas) has a low sulfur content. The opposite is sour crude.

There is light crude and heavy crude (like some California oil). This is a term meaning viscosity and also ease of extraction.

Sounds like a basket of wine or perhaps fruit -- or cigarettes!

"Opec's basket price is an average of the prices for:

Saudi Arabia's Arab Light
The United Arab Emirates's Dubai
Nigeria's Bonny Light
Algeria's Saharan Blend
Indonesia's Minas
Venezuela's Tia Juana Light
and Mexico's Isthmus"

Your car doesn't run on bunker oil. It runs on gasoline or on diesel fuel. Sweet, light oils are acceptable by more refineries, and yield more of the products that are in high demand: gasoline, kerosene, diesel, etc.

When Saudi Arabia increased its production a few months ago, it mostly increased its production of sour sludge. That's why it didn't have much affect on the markets.

Sweet - no H2S (Hydrogen Sulfide)
Sour - has H2S

Added -> <<I gave this answer is because I know only about the drilling side. A 'sour' well is one that produces H2S. This is a very lethal gas and the term sour comes from it smelling like rotten eggs at low concentrations.>>

Light refers to the types of hydrocarbons in the oil. Certain places, like parts of canada (and i think california) produce heavy crude, which contains alot of asphaltines.

crude oil is simply unrefined oil.

This is my take on it.

They like "cheaper" to refine.

And what sweet, light, crude is the lowest sulpher content in the world?

Yes, you are correct: Iraq!!!

Types of Crude Oil

The petroleum industry often characterizes crude oils according to their geographical source, e.g., Alaska North Slope Crude. Oils from different geographical areas have unique properties; they can vary in consistency from a light volatile fluid to a semi-solid. Classification of crude oil types by geographical source is generally not a useful classification scheme for response personnel because they offer little information about general toxicity, physical state, and changes that occur with time and weathering. These characteristics are primary considerations in oil spill response. The classification scheme provided below is more useful in a response scenario.

Class A: Light, Volatile Oils. These oils are highly fluid, often clear, spread rapidly on solid or water surfaces, have a strong odor, a high evaporation rate, and are usually flammable. They penetrate porous surfaces such as dirt and sand, and may be persistent in such a matrix. They do not tend to adhere to surfaces; flushing with water generally removes them. Class A oils may be highly toxic to humans, fish, and other biota. Most refined products and many of the highest quality light crudes can be included in this class.

Class B: Non-Sticky Oils. These oils have a waxy or oily feel. Class B oils are less toxic and adhere more firmly to surfaces than Class A oils, although they can be removed from surfaces by vigorous flushing. As temperatures rise, their tendency to penetrate porous substrates increases and they can be persistent. Evaporation of volatiles may lead to a Class C or D residue. Medium to heavy paraffin-based oils fall into this class. Types of Crude Oil

The petroleum industry often characterizes crude oils according to their geographical source, e.g., Alaska North Slope Crude. Oils from different geographical areas have unique properties; they can vary in consistency from a light volatile fluid to a semi-solid. Classification of crude oil types by geographical source is generally not a useful classification scheme for response personnel because they offer little information about general toxicity, physical state, and changes that occur with time and weathering. These characteristics are primary considerations in oil spill response. The classification scheme provided below is more useful in a response scenario.

Class A: Light, Volatile Oils. These oils are highly fluid, often clear, spread rapidly on solid or water surfaces, have a strong odor, a high evaporation rate, and are usually flammable. They penetrate porous surfaces such as dirt and sand, and may be persistent in such a matrix. They do not tend to adhere to surfaces; flushing with water generally removes them. Class A oils may be highly toxic to humans, fish, and other biota. Most refined products and many of the highest quality light crudes can be included in this class.

Class B: Non-Sticky Oils. These oils have a waxy or oily feel. Class B oils are less toxic and adhere more firmly to surfaces than Class A oils, although they can be removed from surfaces by vigorous flushing. As temperatures rise, their tendency to penetrate porous substrates increases and they can be persistent. Evaporation of volatiles may lead to a Class C or D residue. Medium to heavy paraffin-based oils fall into this class.

Class C: Heavy, Sticky Oils. Class C oils are characteristically viscous, sticky or tarry, and brown or black. Flushing with water will not readily remove this material from surfaces, but the oil does not readily penetrate porous surfaces. The density of Class C oils may be near that of water and they often sink. Weathering or evaporation of volatiles may produce solid or tarry Class D oil. Toxicity is low, but wildlife can be smothered or drowned when contaminated. This class includes residual fuel oils and medium to heavy crudes.

Class D: Nonfluid Oils. Class D oils are relatively non-toxic, do not penetrate porous substrates, and are usually black or dark brown in color. When heated, Class D oils may melt and coat surfaces making cleanup very difficult. Residual oils, heavy crude oils, some high paraffin oils, and some weathered oils fall into this class.

Class C: Heavy, Sticky Oils. Class C oils are characteristically viscous, sticky or tarry, and brown or black. Flushing with water will not readily remove this material from surfaces, but the oil does not readily penetrate porous surfaces. The density of Class C oils may be near that of water and they often sink. Weathering or evaporation of volatiles may produce solid or tarry Class D oil. Toxicity is low, but wildlife can be smothered or drowned when contaminated. This class includes residual fuel oils and medium to heavy crudes.

Class D: Nonfluid Oils. Class D oils are relatively non-toxic, do not penetrate porous substrates, and are usually black or dark brown in color. When heated, Class D oils may melt and coat surfaces making cleanup very difficult. Residual oils, heavy crude oils, some high paraffin oils, and some weathered oils fall into this class.

http://web.ask.com/redir?u=http%3A%2F%2Ftm.wc.ask.com%2Fr%3Ft%3Dan%26s%3Da%26sv%3Dza5cb0dda%26uid%3D08EC4AB1014800614%26sid%3D1DAE4EDE040C50624%26o%3D10234%26qid%3D209B5DDAB4FF494C8B0B0707CD229DFA%26io%3D0%26ask%3DTypes%2Bof%2BCrude%2BOil%26uip%3D4321d898%26en%3Dte%26eo%3D-100%26pt%3DTypes%2520of%2520Crude%2520Oil%252C%2520Oil%2520Program%252C%2520US%2520EPA%26ac%3D24%26qs%3D6%26pg%3D1%26ep%3D1%26te_par%3D191%26te_id%3D%26u%3Dhttp%253a%252f%252fwww.epa.gov%252foilspill%252fcrude.htm&bpg=http%3A%2F%2Fweb.ask.com%2Fweb%3Fq%3DTypes%2Bof%2BCrude%2BOil%26o%3D10234%26page%3D1&q=Types%20of%20Crude%20Oil&s=a&bu=http%3a%2f%2fwww.epa.gov%2foilspill%2fcrude.htm&qte=0&o=10234&abs=Types%20of%20Crude%20Oil%20...%20The%20petroleum%20industry%20often%20characterizes%20crude%20oils%20according%20to%20their%20geographical%20source%2C%20e.g.%2C%20Alaska%20North%20Slope...&tit=Types%20of%20Crude%20Oil%2C%20Oil%20Program%2C%20US%20EPA&bin=&cat=wb&purl=http%3A%2F%2Ftm.wc.ask.com%2Fi%2Fb.html%3Ft%3Dan%26s%3Da%26uid%3D08EC4AB1014800614%26sid%3D1DAE4EDE040C50624%26qid%3D209B5DDAB4FF494C8B0B0707CD229DFA%26io%3D%26sv%3Dza5cb0dda%26o%3D10234%26ask%3DTypes%2Bof%2BCrude%2BOil%26uip%3D4321d898%26en%3Dbm%26eo%3D-100%26pt%3D%26ac%3D28%26qs%3D6%26pg%3D1%26u%3Dhttp%3A%2F%2Fmyjeeves.ask.com%2Faction%2Fsnip&Complete=1

The oil industry classifies "crude" by the location of its origin (e.g., "West Texas Intermediate, WTI" or "Brent") and often by its relative weight or viscosity ("light", "intermediate" or "heavy"); refiners may also refer to it as "sweet", which means it contains relatively little sulfur, or as "sour", which means it contains substantial amounts of sulfur and requires more refining in order to meet current product specifications.

http://en.wikipedia.org/wiki/Petroleum#Classification

Oil is sold on the market based on physical properties which determine how it is refined and how much valuable product (eg gasoline) can be produced from it. Refining of oil is basically inputing energy to separate the oil into a range of lighter (eg gas) an heavier (eg asphalt) fractions, and also some further processing to squeeze more of the desired lighter fractions out of the crude oil.

Crude oil is simply a generic term for any oil recovered from an oil well which has not been refined. Light oil is relatively less dense oil that will yeild more of the lighter refined fractions (as opposed to heavy oil). Sweet oil is crude oil that contains little sulfur, which requires further processing to remove when converting to useable products (as opposed to sour oil). Generally, light sweet crude commands the highest selling price.

... the percentage of 'light' compounds which can be 'cracked' or refined from the crude oil. The lighter compounds are generally more expensive and saleable.

looking up this topic and posting your responses.

Have a great weekend!