Showing posts with label offshore. Show all posts
Showing posts with label offshore. Show all posts

Sunday, December 3, 2017

New Platforms Design Withstand North Sea Conditions

oil gas platform offshore

The pressure to reduce the cost of new developments has never been greater for North Sea operators. The combination of low oil prices, decreased North Sea development opportunities and increased competition from the U.S. shale industry means the industry is being forced to adapt to new ideas.

One development concept that is starting to gain traction is the use of low-cost wellhead platforms for the development of small satellite fields. These are typically newly discovered fields close to an established host platform, which can provide control and power and also carry out fluid processing. Although wellhead platforms have long been a favorite in the shallow waters of the southern North Sea, up until now the preferred option for the development of satellite fields in deeper water has been to use a subsea manifold with a tieback to the host facility. Subsea manifolds are tried, tested and trusted, but WorleyParsons has carried out several studies showing that subsea manifolds don’t necessarily provide the best value solution for a multiple well development. The difficulties and additional costs associated with maintenance and future well intervention operations can all contribute to increased costs over the lifetime of a project.

WorleyParsons has accumulated a reference list of more than 500 installations that are currently operating throughout the world, and its team has combined its experience with ideas borrowed from the shale industry—where standardization and modularization of equipment is the key to low-cost field development. The company has come up with a new concept in wellhead platforms suitable for installation in deeper water and able to withstand North Sea conditions.

The new design uses piled foundations, can be deployed in water depths of up to 120 m (394 ft) and provides space for a maximum of 12 well slots. No accommodation has been provided for personnel, who will gain access for four monthly maintenance visits by vessels equipped with a “walk-to-work” gangway. The platform design includes a 5-tonne crane and sufficient deck space to allow full access for future well intervention. WorleyParsons also has designed the new platform for construction in its covered yard near Stavanger, Norway, with one flat side to permit installation by either barge launch or jackup platform to widen the choice of installation contractor.

The platform is designed with a “design once, build many” approach to capture economies of scale and efficiencies more closely associated with a production line than a North Sea construction yard. The design borrows from the philosophies that WorleyParsons has previously followed in the Persian Gulf and Gulf of Thailand and uses a minimum number of different profiles to reduce procurement and stockholding costs.

Topsides and jacket weights are comparable to more traditional North Sea designs at about 650 tonnes and 3,500 tonnes, respectively, for a 100-m (328-ft) water depth platform, with almost all of the topsides and much of the jacket being identical for any platform regardless of water depth. However, there is scope for significant savings in project schedule by both reducing setup times and by allowing construction to start in parallel with detailed design. The design is so standardized that water depth, seabed conditions and well slot arrangement are the only pieces of information required to completely define an individual platform, further reducing project schedule and minimizing construction risk.

WorleyParsons sees an immediate market for at least 20 lowcost modularized platforms in the Norwegian sector of the North Sea alone and is talking to several operators who have been carrying out studies to assess their viability. They also see applications in U.K. waters, where the upcoming 30th licensing round will be targeting small pool discoveries that will require especially low-cost development schemes.
Read MoreNew Platforms Design Withstand North Sea Conditions

Friday, November 17, 2017

What is Offshore Drilling ?


Offshore oil extraction is an oil extraction technique that allows petroleum companies to access oil deposits buried beneath the ocean floor. Mostly, offshore drilling sites are located on the continental shelf, though drilling technology advancements have made even more economically and physically feasible sea platforms. Many people oppose offshore oil extraction, due to concerns about its impact on the environment, and effectively the imperfections of oil platforms off the coast.

Many sections of the Earth's oceans have massive oil deposits buried deep beneath the surface, and these petroleum deposits are extremely attractive to many oil companies. The first offshore oil drilling operation was founded in 1938 in the Gulf of Mexico, and other manufacturers have quickly started to follow the example of other regions of the world. Since 1970, many communities have issued specific prohibitions against offshore drilling, and the problem has become the source of discord in some areas.

There are several ways in which you can run an oil offshore drilling operation, and the type of rig oil used is usually dependent on the depth in position, type of oil, and prevailing conditions. Classicly, fixed installations are integrated into the ocean floor, with heads and more parts and adjustable to allow oil extraction technicians from the surrounding area. Floating plants are also used in some regions, and in some areas offshore oil extraction is also carried on ships for greater mobility.

Working on an offshore drilling rig can be extremely dangerous. Several accidents have caused plants to explode, overturn, or become severely damaged, accompanied by loss of life, and many crews are now housed out of the home so that if something happens to the rig, the loss of life will be less serious. Workers on oil platforms still have to deal with adverse weather conditions, problems with the drilling rig, and geological conditions that could become dangerous and are generally well paid in recognition of the risks of the industry.

The environmental effects of offshore drilling are mainly caused by pollution related to poor maintenance and management facilities. Oil spills around drilling rigs are common, especially at the bottom of the sea, where drilling can stimulate infiltration, and heavy metal pollution may also occur. Some people think it disrupts offshore oil rigs and confuses marine life, although ironically plants can also provide shelter for sea birds and fish.


Read MoreWhat is Offshore Drilling ?

Thursday, November 16, 2017

Fixed Platform for Oil-Gas drilling and Production

oil gas drilling platform

A fixed platform is a permanent structure attached to the bottom of the ocean, often for the purpose of offshore oil extraction. Most of the work space of this platform is lifted over the surface of the sea from rigid steel or concrete supports. This rules a fixed platform with mobile platforms floating on the surface of the sea and anchored to the bottom of the ocean by more or less flexible moorings. Fixed platforms are typically deployed in water less than 1,700 feet (520 meters) in depth, with deeper drilling activities requiring more complex mobile platforms.

The first productive offshore oil wells were drilled in Ohio Grand Lake St. Marys State Park in 1891, using fixed platforms set on wooden piles at the bottom of the lake. In 1947, the first fixed platform drilling rig located beyond the view of the earth was built in the Gulf of Mexico. Fixed platforms were the most common method of offshore drilling for most of the 20th century, although the first mobile drilling rigs were operating since the early 1930s. Due to their high stability, depth limitation, and high, modern cost Fixed platform drilling rigs are limited to long-run drilling operations in shallow waters.


Fixed platforms are connected directly to the bottom of the ocean by a structural support known as a jacket. The first jackets consisted of concrete foundation poles, while modern deep water jackets are the tough towers of steel tubular supports. The base of a coating can be several times larger than the top, and are often driven deep into the ocean floor mud for support. The jackets are either partially or entirely built to the ground and shipped to the deck's position on bargain tugboats. Once there, they dropped to the bottom of the ocean with the help of ROV, and pushed them into position using bats mounted on barges.

The bridges that form the work space of a platform are generally built on sheltered yards or bays. While the first barges were towed on barges, many modern bridges are built to float during transit. They got to the top of the waiting jacket using hydraulic jacks or barges, and are usually quite high above the floating line to avoid all but the biggest waves. Bridges can be up to 200 feet (60 meters) in diameter, and consist of several levels of work and living space.

If a fixed platform is near the shore, you can pump oil directly from the onshore drilling site of storage facilities through gas pipelines provided along the ocean floor. In the case of drilling operations far from the ground, the platform must include large reservoirs containing the oil as long as it can be transferred to a tanker. Storage tanks are often located below the floating line, where they serve as a ballast to help the platform withstand the power of waves and currents.


Read MoreFixed Platform for Oil-Gas drilling and Production

Investment for Offshore Rig


Offshore drilling is a technology-heavy industry, and if you want to invest in companies that work in this space of goods, you want to be familiar with the associated terminology.

Since offshore drilling can take place in unforgiving places, companies need to implement specific boats for specific drilling projects. These ships are among the most technologically advanced man-made structures. Some ships are designed to withstand strong winds and high waves. Others are more suitable for exploratory projects in shallow waters and need to move from one place to another quickly.

Here are the names of some of these pots you can expect to come across as you start investing in offshore drilling companies:

  • Barge drilling: The drilling barge is one of the most agile vessels on the market. It is a floating device usually towed by a tug to hit puncture positions. The drilling barge is mainly used in the inland, still shallow waters, such as rivers, lakes and swamps.
  • Jack-up rig: The rig jack-up is a hybrid vessel that is part floating barge, part drilling platform. The jack-up drilling rig is towed to the desired position, usually open, shallow waters where its three "legs" are lowered and "jacked" towards the seabed. When the legs are fixed, the drilling platform is raised to the desired levels to allow for safe drilling.
  • Submarine Rig: The submersible rig is similar to the rig jack-up, as it is mainly used for shallow water drilling and is fixed to the bottom of the sea.
  • Semi-submersible plant: sometimes referred to as a seed, this structure is a stunt of modern technological development. It's like a submersible, except that it has the ability to pierce deep in adverse weather conditions and not forgive. 
  • The drilling platform is high and sits on top of a floating structure that is semi-submerged in water (hence the name) and secured by large dowels that can weigh up to 10 tons each.
  • Drill Ship: The drilling vessel is essentially a ship with a drilling deck. It is perhaps the most versatile drilling tool as it can easily be sent to remote offshore locations, including deepwater drilling.
  • Offshore Oil Platform: When one of the previous vessels discovers a commercially viable offshore oilfield, a company may decide to build a permanent platform to exploit this discovery. Insert the offshore oil platform. These facilities are a spectacle to see and are really from the floating city man. They are staffed, they include homes, and are often equipped with shelter. They are ideal for difficult conditions in deep waters.

Read MoreInvestment for Offshore Rig

Wednesday, November 1, 2017

CONVENTIONAL OIL


Definition Oil is a hydrocarbon formed over thousands of years from the decomposition of dead plants and organisms. Intense heat and pressure on this material triggers a reaction, which leads to the creation of oil

Conventional oil is a term used to describe oil that can be produced (extracted from the ground) using traditional drilling methods.  It is liquid at atmospheric temperature and pressure conditions, and therefore flows without additional stimulation.  This is opposed to unconventional oil, which requires advanced production methods due to its geologic formations and/or is heavy and does not flow on its own. 

You may have heard of these terms used to distinguish different types of oil:

​Light vs. Heavy - this refers to the density of oil and its ability to flow.  Lighter oil can be refined with minimal processing due to higher fractions of light hydrocarbons.
Sweet vs. Sour - this refers to the sulphur content of the oil, sulphur must be removed prior to refining.  When oil has sulphur greater than 0.5% it is referred to as "sour."
Because of these variations, oil quality is a spectrum and the distinction between conventional and unconventional is not always black and white. Generally, however, if traditional drilling techniques are used in the oil production it is considered conventional regardless of its physical properties.

Conventional oil is produced using drilling technologies that utilize the natural pressure of an underground reservoir.  Production of a conventional oil well has four main phases[2]:

Exploration: Geological exploration is a series of technologies that are used by geologists and geophysicists to predict the location and extent of underground oil reservoirs.
Drilling: Once a reservoir has been located with sufficient certainty, a drilling rig is used to bore a hole from the surface to the oil reservoir.  Piping is then inserted, allowing the oil to be brought to the surface.  Some of the oil in the reservoir will be produced using the natural pressure of the reservoir.  
Pumping: Gradually the pressure of the well will decrease as oil is produced. At this point a pump will be connected to allow the remaining oil to be extracted.
Abandoning: After all the economically viable oil has been extracted from the well, the well is filled with cement to prevent any hydrocarbons from escaping and a special cap is placed over it to protect the area[3].
Context

Conventional oil tends to be less expensive and complex to extract than unconventional oil due to the routine nature of the production techniques.  This oil is also the most valuable in global markets because it requires the smallest amount of processing prior to refining to create value-added products. Consequently, many of our global conventional oil supplies have already been extracted, limiting the availability of these source for future extraction[2].

Generally, drilling and well abandonment are well-understood and regulated processes but there are always risks with such industrial operations. In drilling, pressure must be regulated carefully to avoid accidents and immediate environmental impacts like land disturbance must be carefully monitored.  After abandonment, well leaks can occur if improper procedures were taken.  

As with all fossil fuel production, there are also concerns with greenhouse gas emissions from their combustion 
Read MoreCONVENTIONAL OIL

Steerable Downhole Mud Motor - Directional Drilling

Steerable Downhole Mud Motor (SDMM) commonly referred to as Mud Motor or Drilling Motor acts much as a positive displacement motor which provides additional rpm to the drill bit from the flow of drilling fluid (mud).

This drilling motor is far different from an electrical motor in it's working principle and operation.
(A lot of people get confused initially)

Since its introduction, the positive displacement motor has undergone revolutionary changes and improvements. Downhole drilling motors have proven to be successful in the most rigorous of drilling environments. From the time of its inceptions, the mud motors have gone extensive improvements that has enhanced its performance, operational and economical reliability. 


Today there are numerous players in the industry providing mud motors for different operational requirements. Few to name are National Oil Varco (NOV), Schlumberger, Halliburton, Baker Hughes, Weatherford, Cavo, Bico, Jaguar, APS, etc. Different mud motors provided by different companies vary a little from each other but, there basic operating principle remains the same. 

Mud Motors have extensively wide range of applications and few of them are listed below:

Conventional Directional Drilling
Side-Tracking
Performance Drilling
Short/Medium/Ultra-short Radius Wells
Air/Foam or Under-balanced Drilling 
ERD Wells
HP/HT Wells
Coiled Tubing Drilling
Vertical Drilling
Casing Drilling
Milling
Coring
Slim Hole Drilling

Working Principle
Mud motors converts the flow energy of drilling fluid (mud) in rotational motion that's utilized in rotating drill bits at a much higher rpm. 
It's imperative that flow rate can be used to control the rpm of the drill bit as per operational requirements. Flow rates for muds are provided by the mud pumps.

Bit RPM = {Flow rate (in GPM) x RPG (Revolutions Per Gallon)} + Rotary RPM 

Note: 
RPG is defined as the revolutions made by bit box and in turn bit, when one gallon of mud flows through it & is mentioned by the manufacturer for each type of SDMM.
While sliding rotary rpm will be zero.

Parts of SDMM:


Simple classification of SDMM parts can be categorized as: 
Top Sub Options
Power Section
Drive Shaft Assembly
Adjustable Bent Housing Assembly
Bearing Assembly
Bit Box

Top Sub options

Top Sub: 
Top sub is simply a cross over housing at the top end of the motor. The lower connection uses a thread that connects to the upper box of the stator housing.

Dump Sub:
It contains a Dump Valve Assembly. This allows the mud to fill or drain from the drill string while tripping.


To avoid the ingress of solids from the annulus when the pumps are off, it’s normal to run a float sub as close to the motor as possible.
The motor will function perfectly without a dump valve - It can be laid down and replaced by a sub having the same connections or run with the ports blanked-off. 
Failure of the dump valve assembly can cause sometimes serious troubles.

Motor Catch & Rotor Catch Top Subs:
The rotor catch system is designed to retrieve the motor in case of a housing fracture. It will retrieve the motor from the upper stator box connection down to the drill bit. The motor catch system has the additional feature of an integral catch flange within the top sub. It will retrieve the motor from the top sub down to the drill bit.


Power Section

Positive Displacement Motors (commonly called a PDM) are reverse applications of a Moineau pump or screw pump. 

It mainly consists of Rotor & Stator.  
Rotor is chrome-plated alloy steel of spiral-helix shape. 
Stator is a hollow steel housing, lined with a molded-in-place elastomer rubber compound. 




A spiral-shaped cavity is produced in the stator during manufacturing. The rotor is produced with matching lobe profile and similar helical pitch to the stator, but with one lobe less. The rotor can therefore be matched to and inserted inside the stator. When assembled, the rotor and stator form a continuous seal along their matching contact points. Fluid is pumped into the motor’s progressive cavities. The force of the fluid movement causes the shaft to rotate within the stator. Thus, it is a positive displacement motor. The rotational force is then transmitted through the connecting rod and drive shaft to the bit.

  






Stage is the distance measured parallel to the axis between two corresponding points of the same spiral lobe. This distance is commonly referred to as the lead of the stator. A slight interference fit between rotor OD and stator ID controls motor power. 

Mud motors are divided into slow-speed, medium-speed and high-speed types. This is done by changing the pitch of the motor stages, by the number of "lobes" and resultant cavities of the stator. 
The greater the number of lobes, the higher the motor torque and the lower the output RPM. 




Increasing the flow rate through a given power section directly increases the output speed. To increase the output speed of a power section without changing the flow rate, the cavity size is changed. A high speed power section will require a larger fluid inlet area (cavity) to allow more fluid throughput into the cavity.
The torque generated by the power section is proportional to the differential pressure applied across the power section and is independent of fluid flow. Generally, the more weight applied to the bit, the higher the torque needed to keep the bit turning, so the higher the differential pressure across the Power Section.
The maximum recommended differential pressure is limited by the stator elastomer. If pressure increases beyond the limits of the elastomer, the stator elastomer will deform, breaking the cavity seal so the mud flow leaks past the rotor and rotation stops – this is commonly known as a stalled motor.


Drive Shaft Assembly

The drive shaft assembly converts the eccentric motion of the rotor into concentric rotation for the bearing assembly via a connecting rod attached to the lower end of the rotor. It transmits the torque and rotational speed from the rotor to the drive shaft and bit. Universal joints convert the eccentric motion of the rotor into concentric motion at the drive shaft. 

It also accommodates any angle set on the adjustable bent housing (or fixed bend housing) and carries the thrust load from the rotor caused by the pressure drop across the power section.


Adjustable Bent Housing
ABH connects stator to the bearing assembly and also houses drive shaft assembly. It has a field adjustable angle-setting to produce a wide range of build rates.



Angle setting may be set to zero for vertical drilling or may be set to any other angle setting as desired. Once the angle is set for the mud motor, it can't be changed when it's down hole and has to be pulled out of the hole to change the angle-setting.
Higher rotary rpm could be used at low angle-setting as compared to a high angle-setting.
Drilling at a higher rotary rpm provides a drill bit with more torsional force provided by the entire rotating drill string as compared to the torsional force provided alone by the mud motor.
(That's the reason why ROP in rotary mode > ROP in sliding mode)

Bearing Assembly
The drive shaft assembly is supported within the bearing housing by radial and axial thrust bearings. It transmits the rotation of the drive shaft assembly to the drill bit and the compressive thrust load created by the weight of the collars and drill string to the rotating bit box & supports the radial and bending loads developed while directional drilling.  
It also carries the tensile off-bottom thrust load produced by the pressure drops across the rotor and the drill bit, as well as any load caused during back reaming. The high capacity radial bearings readily withstand side loads caused by drilling with a deflection device or uneven cutting action along the drill bit periphery. The tungsten carbide radial bearings and angular contact bearing section supports the radial loads along the full length of the bearing assembly, creating a very stiff, strong assembly

Types of Bearing Assembly-
Mud Lubricated Bearing Assembly
Oil Sealed Bearing Assembly
Mud Lubricated Bearing Assembly regulate the flow of mud through the bearing assembly. This diverted mud (usually 4 - 10%) is used to cool and lubricate the shaft, radial and thrust bearings. It exits to the annulus directly above the bit sub. The exact percentage of mud diverted is determined by the condition of the bearings and the pressure drop across the bit. Mud lubricated bearing assemblies can be used in the hottest holes with the lowest aniline point drilling fluids, as there are no elastomeric seals.

Oil Sealed Bearing Assembly is an alternative to the mud-lubricated bearing. A sealed bearing would be recommended where corrosive muds are used, where a lot of LCM of various sizes is pumped or where there is a requirement for a very low pressure drop across the bit (Pbit).



Bit Sub
At Bit sub the drill bit is make up with the motor and it's the only moving external part of the motor.
  

Note: 
In addition to above, different manufacturers can have more or less parts.
The operating conditions and parameters for the mud motors may vary for different manufacturers.
Read MoreSteerable Downhole Mud Motor - Directional Drilling

Friday, June 16, 2017

Work on oil rig


Working on an oil rig? Work on oil rig is possible without a degree. Offshore companies offer excellent career opportunities. Any employee who works on an oil rig must be in good condition and can yield a high concentration for a long time. Working on an oil rig (offshore work) is different from working on land (onshore).

A working on an oil rig

A working on an oil rig is not a traditional working day of eight hours but usually 12 hours a day 7 days a week. To keep these twelve full hours are (usually) four breaks which can be eaten four times. After 12 hours of hard work is quite 12 hours. It is important to find a good rhythm of work and rest 12 hours to 12 hours in order to stay mentally and physically fit. The advice is to catch sleep at least 8 hours. About how workers on an oil rig rest can be read in the following paragraphs. There is no traditional workweek because we work seven days a week with no days off. The big advantage of working on an oil rig is also working a month are released after a month. Often, this is done on 4 weeks and off in a time period of 4 weeks. In the six months of active work there is "enough" money earned for the whole year. Incidentally, all expenses incurred covered by traveling through the employer. On the working conditions of offshore employers you do not have to worry. These are above average. The workday is long and quite heavy by the conditions of cold winds and very hot days. This cuts there if you have to work in these conditions for a long time. This is a good mental and physical condition required.

Work and rest

After working on the rig you have 12 hours of rest. It is important to sleep well in these 12 hours. Of course relaxation is also an important point. There are therefore affected in almost all oil rigs amenities. You can think of a common space with TV, computer, pool table and the like. The facilities on the rig are generally better hotels. So rigs also have sports facilities. Larger rigs even have a soccer field, basketball court, and the like. This makes working for a long time on an oil rig more pleasant. Important to know is that there is also very little privacy making work and life makes on an oil rig also mental strain. Can someone good with these conditions than working on an oil rig is a lucrative and interesting job with many career opportunities.
Read MoreWork on oil rig

Friday, June 2, 2017

Drilling Rigs Type



There are many different types of drilling rigs. Which rig selected depends on the specific requirements of each drill site. Roll your mouse over each picture to see what kind of rig it is.Its a good for drilling knowledge

Land Based Drilling Rigs - The land-based drilling rig is the most common type used for exploration. This site is using a conventional, land-based drilling rig that is smaller and more efficient than those used in the past.

Slim Hole Drilling Rig - A conventional drill bore might be 18 inches in diameter; a slimhole bore can be as little as 6 inches. A slimhole well drilled to 14,760 feet may produce one-third the amount of rock cuttings generated by a standard well. The size of the drill site can be as much as 75 percent smaller, since slimhole equipment requires less space than conventional equipment. However, slimhole drilling is not technically feasible in all environments.

Coiled Tubing Drill Rig - Conventional wells are drilled using sections of rigid pipe to form the drill string. In some cases, coiled tubing technology can replace the typical drill string with a continuous length of pipe stored on a large spool. This approach has many benefits, including reduced drilling waste and minimized equipment footprints, so it is especially useful in environmentally sensitive areas. This technology is best suited to re-entering existing wells, and when multiple casing wells are unnecessary.

Jackup Drill Rigs – These rigs may be used in relatively shallow water -- less than 300 feet deep. A jackup rig is a floating barge containing the drilling structure that is outfitted with long support legs that can be raised or lowered independently of each other. The jackup, as it is known informally, is towed onto location with its legs up and the barge section floating on the water. Once at the drilling location, the legs are jacked down onto the seafloor, and then all three legs are jacked further down. Since the legs will not penetrate the seafloor, continued jacking down of the legs raises the jacking mechanism attached to the barge and drilling package, and slowly lifts the entire barge and drilling structure to a predetermined height above the water. These rigs are extremely strong, since they have to withstand ocean storms and high waves. These rigs are moved by simply by moving the legs up and down, which makes them cost-effective and easily shifted out of harm's way during storms.

Semi-Submersible Rigs – Drilling in water deeper than 300 feet demands some kind of floating platform to hold the rig. Semi-submersible rigs are floating vessels supported on large pontoon-like structures that are submerged below the sea surface. As with jackup rigs, the operating decks are elevated as much as 100 or more feet above the pontoons on large steel columns. This design has the advantage of submerging most of the area of components in contact with the sea and minimizing loading from waves and wind. Semisubmersibles can operate in a wide range of water depths, including deep water. Semi-submersibles can either be attached to the ocean bottom using strong chains and wire cables or may utilize dynamic positioning to remain stationary during drilling without anchors.

Drill Ship - For exploration targets farther offshore, specially designed rigs mounted on ships can drill a well in water depths up to 10,000 feet. These rigs float and can be attached to the ocean bottom using traditional mooring and anchoring systems, or utilize dynamic positioning to remain stationary during drilling without anchors.
Read MoreDrilling Rigs Type

Friday, August 19, 2011

Maritime transport on oil tankers



The shipping of oil on board tankers (tankers and super tankers carrying up to 400,000 tons of crude oil), represents more than half of world maritime trade. One can imagine the consequences of oil shortage on commercial! (On others for that matter ...).

Initially the oil was transported aboard wooden casks (barrels). The barrel has remained the unit of exchange used. It is 159 L. Now tankers are designed as huge reservoirs, sometimes divided into several compartments to store oil of different characteristics (including density). So we can better manage the weight distribution on the ship.

Over the past 30 years, many maritime disasters involving super-tankers have been held. They have caused ecological and economic disasters along the coast affected by oil spills. Most of the cleanup costs and compensation were supported by local e local governments. The Coastal Cleanup is in turn often provided by volunteers.

Since then, new oil transport ships are equipped with double hulls, which are supposed to reduce disaster risks. But they do not prevent the practice of degassing, responsible for oil spill at sea ... The single-hulled tankers still represent the vast majority of the park. 
The gigantic size of the super-tankers creates monstrous consumption of fuel, but which are reasonable compared to their carrying capacity. Currently, more than 600 tankers with a tonnage greater than 200,000 tonnes in circulation.
Read MoreMaritime transport on oil tankers

Tuesday, August 16, 2011

EOR - Enhanced Oil Recovery


When the reservoir pressure is insufficient, we proceed to the injection of fluid (s) to force oil to rise. These fluids may be gas (one of the deposit, or liquefied petroleum gas), or water.

Techniques more advanced (and more energy-intensive), such as thermal methods or fluid drive missible, allow to exploit the deposits difficult.

The thermal method involves heating the oil to the fluid (that is to say, reduce its viscosity). The heat comes from the injection of steam or underground combustion.

The fluid drive missible is performed using carbon dioxide or liquefied petroleum gas, lighter. Finally, chemical methods attempt to limit the capillary that holds the oil in the rocks. This is done using polymers or micro-emulsions of oil, water, alcohols and surfactants.
Read MoreEOR - Enhanced Oil Recovery

Saturday, August 13, 2011

Exploration and prospecting for new oil fields



To find oil, we look for sedimentary basins where oil and gas have formed. Gas and oil then had the opportunity to migrate through porous rock capable of holding large quantities. 

In spite of modern tracking techniques (satellite imagery, geophysical, three-dimensional seismic surveys), the discovery of a new deposit is uncertain until the introduction of drilling. Only the latter can confirm the presence of the precious liquid.
Read MoreExploration and prospecting for new oil fields