Electricity Education - Petroleum
Formation of Petroleum
Petroleum, also called crude oil, is a mixture of carbon and hydrogen. It is made up of 83% carbon and 12% hydrogen, with smaller amounts of sulfur, oxygen and nitrogen. It exists as a liquid and has many different appearances in different locations around the world. In most instances it has the appearance of a black, thick and tar-like substance that is extremely volatile.
It formed millions of years ago as sea plants and animals died and became buried on the bottom of the ocean floor. As the years passed, the remains of these dead plants and animals were placed under enormous amounts of heat and pressure caused by the continual addition of sediment deposits. This organic material became coal, crude oil and natural gas.
The oil and gas are then squeezed out of the shale where they were initially deposited and begin to rise through porous sedimentary rocks. These sedimentary rocks include sandstone and limestone. Because natural gas and oil are less dense than water, migration continues until these hydrocarbons reach a layer of impermeable rock. Many times vast amounts of natural gas and oil are collected beneath domes formed by folded sedimentary rocks.
Uses of Petroleum
Refined crude oil produces many finished products such as gasoline and engine lubricants. Most of the finished products are used as a source of energy. Oil accounts for 38% of energy use worldwide.
The transportation sector is another major use for petroleum. Since the invention of the gasoline-powered internal-combustion engine, mechanized transportation has become a way of life. Today, over 95 % of the world's transportation needs are provided for by oil.
Another major use of oil is for space heating in residential areas and commercial buildings. The use of oil in heating became popular after coal was deemed too dirty to use on an everyday basis.
Plastic and rubber products come from refined petroleum. Petroleum products include crayons, bubble gum, ink, tires, ammonia, deodorant, eyeglasses, heart valves, records, televisions, water bottles, asphalt, toys, etc.
How do we get it?
A man drilling for water found petroleum in Titusville, Pennsylvania in 1859. At this time, crude oil became the foremost source of energy. Once the crude oil is found, it is mined by drilling a hole into the reservoir rock. This oil flows up through the ground to the surface and into large pipelines for domestic transport. Most of the time oil is under tremendous pressure and exits the hole on its own; however, sometimes pumps are used for the collection of petroleum from beneath the surface. It is then refined into many different products. Refining is the process in which the lighter products are separated from the heavier components found in petroleum. For instance, gasoline is separated out from other products such as fuel oil and lubricants.
The top five crude oil producing states are Texas, Alaska, California, Louisiana, and Oklahoma. Even with all the oil produced in the United States, however, the country still has to import over 60% of crude oil and petroleum products used annually. The top five producing countries around the world are Saudi Arabia, Russia, United States, Iran and China.
Petroleum: Yesterday, Today and Tomorrow
For most of the 20th century, oil was plentiful and cheap and was, therefore, the resource of choice. That period of ill-advised oil use came to a halt in 1973, when OPEC (Organization of Petroleum Exporting Countries) decided to raise prices and cut production.
Over the past 30 years, prices have skyrocketed and global warming has become a much larger concern. The combustion of oil releases carbon dioxide, sulfur dioxide and nitrous oxides; all of which are considered greenhouse gases and responsible for global warming and acid rain. These negative effects have impacts on human health and the environment.
Now that world oil supplies are estimated to have about 60 years of current consumption remaining; the reserves will be managed more efficiently and force society to the use of more sustainable sources of energy for the future.