Itigtin of nshr and ffshr il Sillg - Report Example

itigаtiоn оf Оnshоrе аnd Оffshоrе Оil Sрillаgе Your name: Institution name: Introduction Oil spills accidents are unfortunately common events in many parts of the world. Most of these oil spills have been accidental, so no one is able to know where, when or how oil spills can occur (AMSA, 2008). Oil spill can happen both in water and on land, at anytime or night or day, and in any weather conditions (API, 2004). Mitigating oil spill is the best measure for avoiding potential damage to the environment and human health. Most oil drilling companies have taken significant steps to ensure they operate responsibly and safely during mining and transportation of crude oil (API, 2004). Some of their safety and planning measures for responding and preventing of oil spills go beyond the regulatory requirements (AMSA, 2008). Most companies recognize oil spill response and prevention capability as an important plan to develop oil resources (Brekne et el, 2005). For example, both Shell and BP have applied a multi-layered well control system that have been designed to mitigate or minimize the risk, so if any one device or system fails to work it should not lead to an oil spill accident. At Shell and BP, these measures are usually regularly tested and audited (Antoine, 1972). In addition, most crude oil drilling companies have been found develop highly advanced technology to prevent oil spills. There are augmented robust prevention systems that have been created to prevent oil spills that go beyond what is required to prevent the impacts and ensure safety (Antoine, 1972). In this report, various mitigation of onshore and offshore oil spill will be analyzed and the report will make conclusion and recommendation based on this analysis. Thorough preparatory work Barriers are a key concept in the oil industry’s that is used to prevent or minimize the risk of crude oil spills and pollute the environment (API, 2004). Before exploration drilling, there is the need of knowing about the formations under the seabed or earth’s ground (API, 2004). The seismic surveys of the ground will give oil exploration company valuable data or information about the oil reservoir and this will help to prevent oil spill and contribute to a safe drilling operation (Adams, 1986). The seismic survey will provide a basic for oil exploration drilling; the exploration company will hire a drilling rig (Antoine, 1972). While the drilling rig should be adapted to the specific exploration and the environmental conditions that are applicable to the area the oil exploration is taking place. Environmental surveys are also conducted prior to the oil exploration in environmentally sensitive locations or areas (Bazilescu and Lyhus, 1996). All oil exploration activities require permission from the respective governments before they get the go ahead to start exploration. In order for oil companies to get permission to drill oil wells, companies are required to submit environmental and safety requirement well in advance describing what they are drilling for and how the oil drilling will be done (Baker, 1983). Emergency preparedness and environmental risk analyses are required to be submitted, together with a description of which barriers that will be employed to prevent oil spills, and which measure the oil company will use in the event that oil spills should occur. These measures and plans form the basis for the exploration permits issued by the relevant authorities’. Blowout Preventer In the unlikely situation that techniques of early detection of oil spill fail, mechanical barriers such as blowout preventer can seal off the drilling well (Baker, 1983). Blowout preventer provides a back-up in case one system should fail (Adams, 1986). Blowout preventer are automatically activated in situation of a power failure on the oil drilling rig. When the offshore oil rig in Deepwater Horizon started to leak crude oil into the Gulf of Mexico, blowout preventers became hot subjects (API, 2004). Oil blowout is not just a fear under water were environment pollution is the concern (API, 2004). It is also important when oil drilling is done on land, where the potential for explosion and fire is high, especially in oil rigs that have large amounts of natural gases. Blowout preventer helps exploration companies to control expulsion of crude oil from the oil rigs. In the early stages of oil extraction, it is common for crude oil to be under pressure. This is because most of crude oil reserves consist of gases (AMSA, 2008). Because gases have a tendency of expanding and pressure is created in oil reserves because they exist in inflexible and confined spaces (Antoine, 1972). The more gas there is, the greater the pressure at the well rig. When oil reserve is breached during exploration and there is an escape route for the pressure, the oil will be carried up the rig and ejected on the earth’s surface (API, 2004). Because the holes that are drilled to access crude oil reserve is relatively narrow and there can be a lot of pressure in the oil well, oils can be ejected up to 50 meters off the ground into the air (Baker, 1983). The more flammable gases such as propane and methane can easily be ignited due to friction that is taking place during blowout, leading to explosion and fire (Antoine, 1972). In sea crude oil exploration, pressure can force crude oil out of a rig crude oil well even at depth of over a kilometer. For example, the Deepwater Horizon blowout which occurred in Gulf of Mexico, was the largest underwater blowout in the oil industry history. Eleven workers at the site were killed by the explosion, while the oil spill was estimated to be between 35,000 to 60,000 barrels of oil into the Gulf each day and the rig well was not repaired for over 90 days. Blowout preventers have been used over the years to stop oil blowout from occurring and have made oil exploration to be more environmentally friendly and drilling for crude oil safer (API, 2004). In a nutshell, Blowout preventers (BOP’s) are mechanical devices that consist of large valves at the top of a rig well that will be closed if the oil exploration crew loses control of formation oil (AMSA, 2008). By closing the BOP’s valve, the oil exploration crews are able to regain control of the crude oil reservoir (Baker, 1983), and procedures can then be started to increase the mud density until it is possible to open the blowout preventer and regain the pressure control of the oil formation. The blowout preventer will be fastened in a steel casing which has been cemented down in the drilling well (Adams, 1986). The blowout preventer will make it possible to physically shutdown in the oil well. It is primarily activated in the event of well kick, i.e. when the crude oil has penetrated into the well reservoirs (Bazilescu and Lyhus, 1996). This may be as a result of pressure in the drilling well being too low in relation to the pressure in the oil reservoir (API, 2004). In order to maintain the control in the well, it is important to ensure that the mud that is found in the well has enough weight. Drilling Mud Figure 3: The drilling mud keeps the pressure in the reservoir under control, and prevents oil and gas from penetrating into the well In geotechnical engineering, drilling mud is a fluid that is used to drill boreholes into the earth’s surface, and is used during oil drilling and on exploration drilling rigs (API, 2004). Drilling mud is a mixture of clay, water, and weighting materials or substances. During oil exploration, mud is pumped down through the drill-string. During oil exploration, cuttings are created, but these holes do not usually pose a big problem until the drilling end because a drill bit requires replacement (Bazilescu and Lyhus, 1996). When such a situation occurs, and the drilling fluid is not used, the cuttings will the fill the well hole again (Adams, 1986). The drilling fluid is used as a suspension tool to stop this problem from happening. The viscosity of the drilling mud increase when the movement decreases (Baker, 1983), allowing the drilling mud to have a liquid consistency when oil drilling is in progress and then turn into solid substance when the drilling exploration process stopped. Drilling mud also helps to control the pressure in a well by offsetting the pressure of the rock formations and hydrocarbons. Weighing agents are added to the drilling mud so that it can increase the drilling mud density and, therefore, its pressure on the well-holes walls (Antoine, 1972). Another main function of drilling mud is that it is used to stabilize the rock structure in the oil well (API, 2004). Special additives are used to ensure that the fluid that is used during drilling is not absorbed by the rock formation structure in the well and that the pores of the rock formation structures are not clogged. The drilling fluid has many functions. It cools and lubricates the drill bit, helps prevent the borehole from collapsing (Adams, 1986). However, the most important function in this context is that the fluid mud keeps the pressure in the oil reservoir under control and prevents oil from penetrating into the well (Bazilescu and Lyhus, 1996). The longer the hole bore, the more drill pipers will be needed to drill the oil well (API, 2004). The amount of pipes need get heavy, and the drilling mud will add buoyancy, reduce stress. In addition, drilling mud helps reduce friction with surrounding rocks, thus reducing heat. This cooling and lubrication helps to prolong the life of the drillbit. Although very rare, oil spills during drilling operations can be as a result of blowouts, when the oil pressure in a drilling well cannot be mitigated and causes the uncontrolled flow of crude oil to the earth’s surface (Baker, 1983). This is less likely to occur when well depth and water depth are shallow and the rock structure is consistently strong, because pressure in the bore hole is more uniform and fewer drill pipe casing will be needed. Limits Volume Figure 4: The blow out preventer consists of 3-5 large valves that can be closed so that oil cannot flow to the surface. If these precautions have failed, there are two factors that can be used to limit how much crude oil is discharged: how long the blowout lasts and the strength of the oil flow. A blow out means that blow out preventer system has failed. However, in most situations, the blowout preventer will help limit the oil spill (AMSA, 2008). The diameter of the borehole has also been noted to have effect on ow strong the oil flow will be in the case of a blow-out. When drilling in relatively shallow oil reservoirs, well drilling can first be done at a smaller diameter, which can subsequently be done to the planned diameter (API, 2004). This will be decrease the volume. All oil exploration activities have plans that are oil spill accident (Antoine, 1972). If a blowout accident has occurs, a relief well will be In many situations, the use of nature can be employed by oil companies to be done through the Modern oil spill preparedness If all the mitigating measures fail to stop oil spills and the oil end up on the sea, oil firms have an oil spill preparedness that will minimize the consequences of the oil spill incidents to the maximum degree possible (Bjerkemo, 2010). For example, oil companies in Norway have (Brekne et el, 2005). NOFO has been able to divide the Norwegian water (Brekne et el, 2005). At all the times, three of the vessels are mobilized at any given time. Oil production in Norway will reduce the overall environmental risk from oil spill accidents and vessels accidents (Brekne et el, 2005). All installations and platforms have systems that detect and monitor potential leakages. Monitoring is done via airplanes, satellites or helicopters. If oil spill has occur, NOFO has been in place with its standby equipments (Bjerkemo, 2010). The quicker these equipments spills (Brekne et el, 2005). A rule of thumb has always stated that 99 per cent of the oil spills is always found in 10 per cent of the accidents or slick (Brekne et el, 2005). Therefore, it is important to keep. Transportation Pipeline Figure 6: An elevated section of the Alaska Pipeline. Crude or refined oil is mostly transported in pipelines and this form of movement of crude oil can be a cause of accidents if oil is being transported over long distance and different climatic conditions (Mohitpour, 2003). For example, approximately 600 kilometers of Alaska pipeline is buried underground, while about 675 kilometers is above ground to avoid burying the pipe in permafrost, which is ground that is continuously frozen for many years (Pattanayek and DeShields, 2013). Because the crude oil is usually warm, heat that is generated from the buried pipe could warm the ground permafrost, making the soil around the pipeline to be unstable, and this may cause leakage on the pipeline (Pattanayek and DeShields, 2013). When the oil pipeline is buried in permafrost ground it is either refrigerated or insulated to keep the permafrost from the surrounding to thawing. The pipeline that is above the ground sits on the vertical support members (VSMs). The 78,000 VSMs is equipped with heat transfer radiators and pipers that keep the permafrost beneath the VSMs frozen (Pattanayek and DeShields, 2013). While in the areas where there is a lot of heat and can cause thawing, the VSM contain double pipes that contain anhydrous ammonia, which vaporizes below the ground, condenses and rises above the ground, removing the ground heat whenever there is excessive heat on the ground (Mohitpour, 2003). Heat is transferred through the walls of the heat pipes to aluminium radiators atop the pipes. In the case of this oil pipeline, much of the ground in Alaska is permanently permafrost or frozen ground (Pattanayek and DeShields, 2013). Heat generated from the oil would thaw the frozen ground if the pipeline was buried, causing the oil pipeline to break and buckle (Mohitpour, 2003). For this reason, more than half of the oil pipeline is built above the ground. In areas of thaw-unstable grounds where the oil pipeline had to be below the ground for animal crossing, highway, or avoidance of avalanches and rockslides, the pipeline is being insulated, to protect the pipeline from permafrost from the heat generated from the crude oil. Read More

Blowout preventer helps exploration companies to control expulsion of crude oil from the oil rigs. In the early stages of oil extraction, it is common for crude oil to be under pressure. This is because most of crude oil reserves consist of gases (AMSA, 2008). Because gases have a tendency of expanding and pressure is created in oil reserves because they exist in inflexible and confined spaces (Antoine, 1972). The more gas there is, the greater the pressure at the well rig. When oil reserve is breached during exploration and there is an escape route for the pressure, the oil will be carried up the rig and ejected on the earth’s surface (API, 2004).

Because the holes that are drilled to access crude oil reserve is relatively narrow and there can be a lot of pressure in the oil well, oils can be ejected up to 50 meters off the ground into the air (Baker, 1983). The more flammable gases such as propane and methane can easily be ignited due to friction that is taking place during blowout, leading to explosion and fire (Antoine, 1972). In sea crude oil exploration, pressure can force crude oil out of a rig crude oil well even at depth of over a kilometer.

For example, the Deepwater Horizon blowout which occurred in Gulf of Mexico, was the largest underwater blowout in the oil industry history. Eleven workers at the site were killed by the explosion, while the oil spill was estimated to be between 35,000 to 60,000 barrels of oil into the Gulf each day and the rig well was not repaired for over 90 days. Blowout preventers have been used over the years to stop oil blowout from occurring and have made oil exploration to be more environmentally friendly and drilling for crude oil safer (API, 2004).

In a nutshell, Blowout preventers (BOP’s) are mechanical devices that consist of large valves at the top of a rig well that will be closed if the oil exploration crew loses control of formation oil (AMSA, 2008). By closing the BOP’s valve, the oil exploration crews are able to regain control of the crude oil reservoir (Baker, 1983), and procedures can then be started to increase the mud density until it is possible to open the blowout preventer and regain the pressure control of the oil formation.

The blowout preventer will be fastened in a steel casing which has been cemented down in the drilling well (Adams, 1986). The blowout preventer will make it possible to physically shutdown in the oil well. It is primarily activated in the event of well kick, i.e. when the crude oil has penetrated into the well reservoirs (Bazilescu and Lyhus, 1996). This may be as a result of pressure in the drilling well being too low in relation to the pressure in the oil reservoir (API, 2004). In order to maintain the control in the well, it is important to ensure that the mud that is found in the well has enough weight.

Drilling Mud Figure 3: The drilling mud keeps the pressure in the reservoir under control, and prevents oil and gas from penetrating into the well In geotechnical engineering, drilling mud is a fluid that is used to drill boreholes into the earth’s surface, and is used during oil drilling and on exploration drilling rigs (API, 2004). Drilling mud is a mixture of clay, water, and weighting materials or substances. During oil exploration, mud is pumped down through the drill-string. During oil exploration, cuttings are created, but these holes do not usually pose a big problem until the drilling end because a drill bit requires replacement (Bazilescu and Lyhus, 1996).

When such a situation occurs, and the drilling fluid is not used, the cuttings will the fill the well hole again (Adams, 1986). The drilling fluid is used as a suspension tool to stop this problem from happening. The viscosity of the drilling mud increase when the movement decreases (Baker, 1983), allowing the drilling mud to have a liquid consistency when oil drilling is in progress and then turn into solid substance when the drilling exploration process stopped. Drilling mud also helps to control the pressure in a well by offsetting the pressure of the rock formations and hydrocarbons.

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