Facilities Engineering - Gazelle Oilfield - Coursework Example

? Facilities Engineering work Gazelle oilfield is located in West Africa in the region of Cote d’Ivoire, and is majorly supported and supervised by Rialto Energy Limited working in the same location. It is actually located at CI-202 and company is now planning for the placement of new reforms for generating more funds by expanding the business. This expansion has been made possible with the support and services of Rialto and the increasing cost of the budget will be consumed for the placement of new oil drilling wells in the field of Gazelle. Although, Gazelle oilfields are majorly used for the production of gaseous products. Here are the CPR results obtained for oil and gas exploration: Figure 1: CPR results of Gas and Oil extracted from Gazelle Well Major products extracted out of the oilfield at Gazelle are liquefied petroleum gas, gasoline, diesel fuel, fuel oils, lubricating oils, paraffin wax, sulfur. Question: Prepare flow schemes showing the architecture of the layout and of the main components used from the wellhead to the point of export for all option. The architectural layout of the Gazelle offshore oilfield is shown below with all the processing units and their respective processing cycles. This is a very large operating unit with extensively large piping layout with fluid streams running along. Crude oil is first passed through an oil production unit which provides the pre-processed oil to the oil storage tank from where it is delivered to the processing plant through a piping system. Here is the detailed flow diagram of all the processes taking place along their sequential flows: Figure 2: Flow Diagram of Gazelle Oilfield with components used in Oil Production Gazelle oilfield is a field that requires extensive production as well as operational refurbishments but even then it is above working above case base oil producing offshore refineries. This oil production unit involves a number of operating units that work extensively for long hours to provide quality product in economical rates with least water cuts. Following is an exhaustive list of components that work as a part of oil refinery at Gazelle(Snow, 2010, Gordon, 2012). De-salter unit is just provided at the inlet of crude oil and is responsible for washing away all the salt from crude oil. Distillator: Crude oil from de-salter is then passed through the distillatory unit which distills the crude oil into fractions. Second stage of distillation is also incorporated just after this by making use vacuum distillation unit which is responsible for the distillation of the left over components of crude oil which were not fractioned by simple distillatory. Hydrotreater: all fractions of the crude oil are then hydrogenated according to their requirements and this process is performed for removing sulfur contents from the oil fractions. Catalytic Reformer: it is used to reform the low grade oil fractions into high grade products like converting gasoline to a higher degree of octane level. While reforming the oil fractions excess amount of hydrogen is produced as a by-product of the process. Fluid Catalytic Cracker: this catalytic cracker is specialized in converting only liquid oil fractions to higher grade of oil. The process of converting gasoline to hi-octane is processed there. Hydrocracker: hydrocracker then takes the oil fractions and hydrogenizes them in order to upgrade the fractions. Visbreaking: the oil fractions that are needed to be degraded to lower order fractions are then passed through visbreaking unit Coking unit: this unit is specialized in carbonizing the heavy oil components of the fractions in order to produce gasoline. This helps in converting maximum oil fractions into consumable products. Alkylation: this unit is specialized in converting low grade molecules to higher ones and hence improving the quality of gasoline. Dimerization: the process of dimerization is performed in order to hydrogenate the gasoline products. Isomerization unit: This unit is specialized in condensing linear molecules into the form of high grade polmers. Steam Reforming: steam reforming unit is specialized in producing quality hydrogen to be used by all the processes taking place within the refinery. This hydrogen can be either taken from the refinery, where produced as a by-product, or can be generated by the unit alone. Storage tanks: Final products from the Gazelle oil refinery are stored in storage tanks from where they are delivered or transported to their required locations in tankers or containers. Here is the diagram showing the detailed architecture of the Gazelle offshore oilfield. This is the refinery unit present at the point of wellhead from where oil is being extracted from the ground. Figure 3: Architecture of Gazelle Oil Refinery at Wellhead Question: Using the data provided and the economic analysis excel sheet ( with a complete Base Case Decline example) carry out an economic evaluation considering the technical cost-(CAPEX+OPEX)/cum oil- of the three options available to develop this field in comparison with the base case. CAPEX is referred to as the capital expenditure and is concerned with all the costs that are required for up building and refurnishing the already existing oil refinery. This cost covers all the new installments at the point of oil producing unit as well as the repairing costs including the repair of walls and roofs of the production unit. The CAPEX for the Gazelle oilfield is listed below: Whereas, OPEX cost is related to the operational cost that is required to keep the refineries running in order to produce a specific amount of oil and other oil fractions in a given time frame. It is the essential cost that is required to keep the system going. Here is the list of tasks that come under the category of OPEX in Gazelle oilfield. As far as cumulative cost for oil is concerned, it is very important in maintaining market position. The capital expenditure (CAPEX) and operational expenditure (OPEX) directly affect the cost of the oil as a finished product. Therefore, at the time of installing the new oil refinery or refurbishing the already working one, a fact is strongly followed that the resulting of cumulative cost of oil must not be altered as compared to the market rate. Therefore, with the passage of time Gazelle oilfield has undergone a number of reforms and now it is placed above case base for a typical oilfield unit. But it still needs much reformation to be followed in order to become more economic and profitable unit. Here is the cumulative oil and gas price being produced at the Gazelle oilfield. The given data shows that the oil refinery is showing decline in terms of performance from case base which has highly affected economic growth of the company, also the water cut has increased. This requires extensive analysis for determining the factors involved and then performing refurbishment of the whole refinery. Question: Discuss the flow assurance issues that may be encountered in the schemes and propose likely solutions to these in particular defining the revised water handling, injection and disposal system. (20%) Oil drilling in deep sea water is much different from oil drilling in shallow sea or onshore in terms of water handling, injection and disposal. While drilling oil from deep sea, water handling is much a great issue to be handled which is not a case while dealing with onshore and shallow water. Also deep water oil drilling requires extensive use of chemicals as compared to drilling oil at any other geographical conditions because while dealing with drilling process under deep water has many issues including excess pressure. Along with high pressures, sea bed temperatures may range from 275 to 35 F. Such high pressure and low temperature require injection of chemicals within the pipelines at the drilling point in order to keep the system working well and make it chemically fit to work at such locations. This can be done by making use of flow assurance techniques provided by a number of vendors. The most common technique is to make use of hydraulic fracturing concept in order to remove contaminant from the drilled oil that may harm the well bore. This technique is combined with production chemistry which helps in overcoming post fracture intervention costs that may incur due to bacteria, corrosion and organic deposition at the oil well bore head for long time(BakerHughes, 2013). Other than the water cut from the oil well, water is used by the drilling system to be injected while drilling oil. This injected water needs to be managed properly in storage places like ponds and wells and must be filtered properly for expected impurities that my harm the bore. This pond water can be collected either from the water cut obtained from oil fractions or by natural resources. This injected water is first treated for contaminants and specialized techniques are used including ionic exchange and adsorptions, and membrane filtration. In case of deep water oil drilling in Gazelle water cut is too much. Therefore, excess water obtained from water cut is most commonly used by on-shore implementation techniques like drip irrigation, reuse by industrial and domestic users and for dust control purposes(Schlumberger, 2013). Question: Critically analyze all options (under clearly identified set of criteria) to develop the Gazelle field from wellhead to point of export (subsurface plan is fixed). Based on your analysis select your recommended option for field development. (30%) Gazelle oilfield is located at greater depth along the coastal area of Africa and is too far from the dry land. Therefore, it has been installed as a stand-alone oil drilling and producing unit with the refinery at the same location. Initially it was too difficult to develop an oil field in deep sea but was only seen onshore or in shallow waters. Therefore, Gazelle oil field is a remarkable achievement of its time. Initially, the production unit of Gazelle oilfield was installed on the coastal area close to the field but it was much depressing situation to lay down such a long and cumbersome piping system from the point of drilling to the production unit(Limon-Hernandez et al., 1999). With the advancement in technology, gazelle oilfield has improved a lot and now it is having a single refinery unit offshore from where the production of oil as well as drilling is taking place simultaneously and the oil is transported to the onshore storage tanks from where it is contained in tankers and containers. In order to develop the Gazelle oilfield, the single refinery unit can be connected to multiple oil drilling locations. It can increase productivity as well as profit margin. In order to achieve this configuration, more well heads are needed to be drilled at remote locations which can then be connected to the single production unit hence decreasing cost and increasing productivity. Here is the pictorial view of the described configuration(Christie et al., 2000). Figure 4: Multiple Wellhead locations connected to a Single Operational Unit In early times the drilling rigs were placed as semisubmersible units but now they are placed floating at the top of the sea level. This arrangement is good for Gazelle as the oilfield is too deep in the ocean and sea divers are unable to reach the point therefore, remotely operated vehicles are used to perform the drilling of well heads and repairing tasks. For the transportation of final product to the onshore storage places Gazelle field needs to upgrade its transportation system. The most advanced system used for the transportation of oil as well as workers to the well head is the underwater tunnel system. There are of the total three tunnels. One is specialized in transporting oil and gasoline whereas rest of two is provided with latest transportation system for transporting equipment, hydrocarbons and labor. Here is the pictorial view of the suggested transportation strategy(Grov et al., 2013). Figure 5: Under Sea Tunnel Question: Prepare an outline decommissioning plan for your recommended development option. (15%) Before determining the decommissioning plan, one must be familiar with the life cycle of the operating facility. The life cycle of the Gazelle oilfield is shown below(Twomey, 2012): Figure 6: Operating Life Cycle of Gazelle Oilfield Decommissioning of the system requires either complete or partial removal of system components due to the end of their life cycle. The gazelle field is provided with a platform which is made up of steel pilled jacket and is provided with a stabilization system as the platform is capable of floating over the sea surface. The drilled oil is transported to the refinery by making use of a transportation system. The system suggested is too convenient and having long life because it is less prone to damage by corrosion or other sea accidents. Under water tunnels when needed to be decommissioned are replaced completely but the cost of drilling tunnel through the underwater land is much reduced(EIA, 2000). Decommissioning process can also be carried out if the tunnel is no more required for the transportation of oil and other substances and in such case all the piping system needs to be removed from the tunnel. As far as decommissioning of water injection system is required it involves the replacement of water storage tank as well as all the changes introduced in FSU(Shell, 2007). References BAKERHUGHES. 2013. Oilfield Water Management Solutions: Managing produced water to extend field life and profitability [Online]. Available: http://www.bakerhughes.com/capabilities/water-management/surface-water-reuse. CHRISTIE, A., KISHINO, A., CROMB, J. & HENSLEY, R. 2000. SubSea Solutions. EIA. 2000. chapter 8: Decomissioning and Abandonment [Online]. GORDON, D. 2012. Understanding Unconventional Oil. Energy and Climate. GROV, E., NILSEN, B. & BRULAND, A. 2013. Subsea tunnels for oilfield development [Online]. Available: http://www.tunneltalk.com/TunnelTECH-Nov2013-Development-of-subsea-tunnel-access-to-offshore-oil-fields.php. LIMON-HERNANDEZ, T., DE-LA-FUENTE, G., GARZA-PONCE, G., EXPLORACION, P. & MONROY-HERNANDEZ, M. 1999. Overview of the Cantarell Field Development Program. Offshore Technology Conference Houston, Texas. SCHLUMBERGER. 2013. Water Services: Oilfield Water Management [Online]. Available: http://www.slb.com/services/additional/water/oil.aspx. SHELL 2007. Brent Facilities Decomissioning. Stakeholder Engagements. Aberdeen and London. SNOW, N. 2010. Experts Examine how Cuba's Offshore Oil could be Game Changer. Oil and Gas Journal. TWOMEY, D. B. 2012. Life Cycle of an Oil and Gas Installation. CCOP & EPPM Workshop on End of Concession & Decommissioning Guidelines. Bangkok. Read More