Here we will learn together about oil drilling process .
After choosing the most likely areas, holes are made, sometimes reaching considerable depths, for example more than 6000 m in the United States.
It begins by building towers metal square with cross braces of 30 m to 40 m in height, to facilitate handling of heavy drilling equipment.
There are two common systems: a drum, which is the oldest and most obsolete and rotation, which is used in most cases.
Method of Oil Extraction Process
Percussion method of oil extraction process:
Using a heavy drill, attached to a master bar that increases its weight, which is supported by a steel cable connected to a rocker, which gives it a reciprocating up and down, being driven by a motor.
Periodically remove the drill bit to remove material or debris, with a tool called a spoon. For its slowness, it has now fallen into disuse, being used only for shallow wells.
Rotation method of oil extraction process
The drill, which is hollow, is bolted to a series of pipes. Steel bars are poll-driven revolving turntable, located at the base of the tower, and connected by a chain drive motor with the control unit.
The rotary table has a hole in the center square, which slides a drill string in the same section, which drops as the drill progresses. From the top of the tower are suspended gear, allowing the heavy lifting and lowering equipment.
Drilling begins with the movement of the rotary table, until it is necessary the addition of new drill pipe, which thread are about 9 m.
“The operation is repeated many times as necessary”
The debris is carried to the surface by pumping a dense suspension, injection consisting of an aqueous suspension of a special clay called bentonite technicians constantly analyze. Besides, this sludge has other 2 important functions: Revokes the walls of the hole, avoiding or preventing landslides, and cooling the drill bit, which is heated in their work hard wear.
When it has drilled 100 to 150 m, the well is piped to a metal pipe and quick-setting cement (cement) to avoid possible landslides caused by seepage of ground water going by. Inside the main driver is continuing the drilling with a smaller diameter drill. In deep wells, these decreases force to begin with diameters of 550 mm.
Injection analysis lets you know when you are near the site, the presence of gases from the same small breaks. It is customary to drill production well layer, which is then piped to a perforated pipe, to know its thickness and to facilitate the upwelling of oil.
The most common is to be drilled vertically. This is achieved by controlling the weight applied to the drill and the speed of rotation. But it can also drilled obliquely, in the so-called directional drilling, deflecting the drill steel concave wedge and probe rods articulated to achieve away from the vertical fields (under populated areas, seas, or to control wells erupting through lateral injection of clay or cement). Currently, it is common to end a well with a cemented, which is then drilled with a drill with bullets.
Offshore drilling of oil extraction process
Another method to increase production of oil fields is the construction and use of drilling rigs on the sea (it has been operating for more oil). These rigs are installed, managed and maintained on a platform located offshore in water depths up to several hundred meters. The platform can be floating or resting on piles anchored in the seabed, and resists the waves, wind and in the Arctic ice. The tower serves to suspend and rotate the drill pipe, one end of which the bit is located, as it penetrates into the earth’s crust are adding additional lengths of pipe to the drill string. The force required to penetrate the soil comes from the own weight of drill pipe.
Upwelling Control in oil extraction process
It begins near the bottom down to a pipe 5 to 7.5 cm in diameter, called pipeline, which carries at its upper end a set of valves and fittings called Christmas tree, which keeps the well under control.
The upwelling of oil through the pipeline, is achieved by natural or artificial methods:
There are three reasons that can cause natural upwelling.
- Underlying water pressure, which when transmitted to oil, which requires climbing. It is the most effective.
- The pressure of free gas that covers the oil, which is transmitted to it and drives him in his rise.
- When there is no free gas and water do not have enough pressure or not there by reducing the pressure for the drilling of the gas dissolved in oil is clear and to expand it raises. Is the least effective of the three.
Can be achieved by two methods:
- Pressure injection of water, gas or air.
- Mechanical pump suction pumps deep, driven by pump jacks. Usually takes place simultaneously pumping a number of neighboring wells, pumping connecting their cats by long steel rods, an eccentric which is rotated at a station central.
- Hydraulic pump, oil pumping pressure pumped back to the surface, and centrifugal pump with multi-stage centrifugal pumps, located near the bottom of the well and driven by electric motors controlled from the surface.
Oil as it emerges, can not be processed industrially without separating by gas and salt water that accompanies it.
Takes place in a battery of tanks, which, by simple rest gas is separated spontaneously.
Destruction of the salt-water oil emulsion
One of the difficult problems facing the oil industry. This is to solve it in different ways:
- It prevents the formation of emulsions, avoiding stirring the mixture of saltwater and oil operations in the insurgency.
- Water washing of the emulsion, followed by a subsequent decanting.
- Settling in storage tanks.
- Spin of the emulsion
- Heated to reduce viscosity of heavy oil
- Chemical, thermal or electrical (which are most effective for desalination and dehydration, works to 11,000 volts).
A once purified, is sent to storage tanks and from them, by distillation, by pipeline or other means of transportation (tankers, tank wagons, etc.).