This is what I would consider as the core of this course, awesome topic.
Would it be logical to say that there are five methods of oil extraction?
What is drilling?
why is water ,steam acids or various mixtures pumped to the oil reservoir.
why the organic deposits in north america is different from middle east when we know accordingly to PANGEA theory once all five continents were one?
Why do petroleum composition vary in different zones of the world
la producción de petroleo puede variar según el costo del barril ya que se requieren muchos procesos para poder extraerlo.
What is Drilling/
What is drilling?
Locating an oil field is the first obstacle to be overcome. Today, petroleum engineers use instruments such as gravimeters and magnetometers in the search for petroleum.
Generally, the first stage in the extraction of crude oil is to drill a well into the underground reservoir. Often many wells (called multilateral wells) are drilled into the same reservoir, to ensure that the extraction rate will be economically viable.
Also, some wells (secondary wells) may be used to pump water, steam, acids or various gas mixtures into the reservoir to raise or maintain the reservoir pressure, and so maintain an economic extraction rate.
Primary oil recovery
If the underground pressure in the oil reservoir is sufficient, then the oil will be forced to the surface under this pressure.
Gaseous fuels or natural gas are usually present, which also supply needed underground pressure.
In this situation, it is sufficient to place a complex arrangement of valves on the well head to connect the well to a pipeline network for storage and processing. This is called primary oil recovery. Usually, only about 20% of the oil in a reservoir can be extracted this way.
Secondary oil recovery
Over the lifetime of the well, the pressure will fall, and at some point there will be insufficient underground pressure to force the oil to the surface.
If economical, and it often is, the remaining oil in the well is extracted using secondary oil recovery methods. Secondary oil recovery uses various techniques to aid in recovering oil from depleted or low-pressure reservoirs.
Sometimes pumps, such as beam pumps and electrical submersible pumps are used to bring the oil to the surface.
Other secondary recovery techniques increase the reservoir’s pressure by water injection, natural gas re-injection and gas lift, which injects air, carbon dioxide or some other gas into the reservoir. Together, primary and secondary recovery allow 25% to 35% of the reservoir’s oil to be recovered.
Tertiary oil recovery
Tertiary oil recovery reduces the oil’s viscosity to increase oil production. Tertiary recovery is started when secondary oil recovery techniques are no longer enough to sustain production, but only when the oil can still be extracted profitably.
This depends on the cost of the extraction method and the current price of crude oil. When prices are high, previously unprofitable wells are brought back into production and when they are low, production is curtailed.
Thermally enhanced oil recovery methods (TEOR) are tertiary recovery techniques that heat the oil and make it easier to extract:
Steam injection is the most common form of TEOR, and is often done with a cogeneration plant. In this type of cogeneration plant, a gas turbine is used to generate electricity and the waste heat is used to produce steam, which is then injected into the reservoir.
In-situ burning is another form of TEOR, but instead of steam, some of the oil is burned to heat the surrounding oil. Occasionally, detergents are also used to decrease oil viscosity. Tertiary recovery allows another 5% to 15% of the reservoir’s oil to be recovered.