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  1. Tight oil High Potential Solution To Energy Our Generation Needs
  2. Unconventional Oil  Crudes form the foundation of Petroleum Industry. They are extracted from reservoir rocks.  Crude Oil can be classified on the basis of it’s density and ease of flow.  Heavy Oil refers to crude that is too viscous to flow in pipeline without dilution.  Conventional Oil are medium to low viscous crudes. They are found in rocks that have enough permeability to let oil flow to the wellbore.
  3. What is Tight Oil  Tight oil is a conventional-crude oil that is found within reservoir with low permeability.  The reservoir rock has low permeability of around 0.1 mD and will not let oil flow easily to the wellbore.  Tight oil is low to medium viscous in nature.  Limestone and Sandstone generally contain tight oil.  They are now being produced because of advanced technologies like horizontal drilling coupled with multi- stage fracturing to stimulate flow of oil.
  4. How is oil stored and released  Oil is stored in pores of rock. These are the empty space in between the grains of rocks.  For the oil to flow to wellbore, the pores must be interconnected to allow easy passage of oil. This property of interconnectedness in rock is called permeability.  From such tight reservoirs, we get crude oil that is light in nature, that means it is low viscosity fluid.  This makes it uneconomical and difficult to produce compared to other crudes found.
  5. Why Produce Tight Oil  Tight oil is a smart alternate to already depleting conventional oil resources.  The oil found in tight reservoirs is of high quality and requires very little refinement on surface.  Current Tight oil reserves are estimated to multiply the current production rates highly, if they can be produced economically and efficiently.
  6. The expected Tight oil Reserve We consume energy at the rate of 8918 MTOE per year. At this rate we will deplete all our reserve in 40 years. If potential tight oil reserves are produced, they will solve this crisis for years to come.
  7. Where to find Tight Oil  Add a map, highlighting the areas where we find reserves. Comment about the country currently exploiting the resource and the effect it had. At present USA has reserves and the technology to produce tight oil. This is a map of it’s reserve.
  8. World Oil Reserve Distribution The next big Tight Reservoir could be anywhere.
  9. Technologies used to recover Tight Oil Techniques used to make recovery worth the effort.
  10. Horizontal Drilling This means extending the wellbore to horizontal direction, to increase the wellbore contact area with reservoir, enabling more oil to flow directly to wellbore Once it becomes horizontal, the horizontal length can extend 3- 4 kms.
  11. Hydraulic Fracturing Once the wellbore is drilled, we need permeability enhancement techniques to induce inflow of oil. This is achieved by fracturing the adjacent rocks in stages hydraulically using fracture fluids which are selected to suit a particular wellbore
  12. Hydraulic Fracturing  One Section is isolated and then fractured hydraulically. Additives in the fracturing fluid prevent closing of fractures.  First section is then closed and we move on to next section, which is isolated from rest of wellbore and hydraulically fractured.  This is continued until desired length has been fractured, resulting in improved permeability  If needed rocks can be fractured again to increase the permeability when it has gone down with time and usage.
  13. Micro Seismic  Micro tremors are used to induce cracks in rock.  They are monitored to ensure correct application using a variety of techniques.  The real time measurements allow us to shape the fracture to ensure optimum production
  14. Footprints and Effects Potential Ground water contamination,
  15. Water Protection The saline water and other formation fluid including crude, that is brought up to surface is kept isolated from adjoining shallower water table. The well is covered in cement and steel casing to provide total and fail proof protection against contamination.
  16. Multi Well Pad We can drill multiple wells from one hole. This is economically viable but needs more care to operate and also has a smaller footprint on environment.
  17. Water Consumption in Hydrofracking The projected total demand for peak Marcellus Shale activity in the same area is 8.4 million gallons per day. This water is basically met from surface water sources such as lakes, rivers and municipal supplies. However, groundwater can be used to augment surface water supplies where it is available in sufficient quantities.
  18. Composition of Hydrofracking fluid Fracking fluid is not chemicals and sand and water. It is so much of fresh water. Something which is already scare now.
  19. Other Effects of Oil and Gas Unconventional Drilling  Due to use of seismic micro waves, many earthquakes in past have been linked to drilling activities. Earthquakes occur more frequently in injection wells vicinity.  The land once drilled is rendered useless which can not be used for various purposes like once it could be.  Accidents like Oil-spill, Flares and Blowouts, harms the environment in irreparable ways.  Factors like noise and dust add to total harm caused to nature.  Construction and explosion required hampers the soil and may trigger geologic calamities.
  20. Possible Improvements and Changes  Instead of using Micro seismic waves to detect the fracture, we can use sensitive devices that can detect Radioactive substances to very exact position if it is close enough. We can send RA tracers along with fracking fluid to tell us the position of fracture and the path fluid will take after fracture  The land rendered useless after the life of play is over, can be used as underground CO2 storage facility plant. There can be many alternative uses in the form of injection or storage wells.  Amount of water used in Hydrofracking is vital, since it comes from fresh water sources. This water can be avoided by switching over to GasFrac technique which utilizes propane gel to create fractures.

Notes de l'éditeur

  1. MTOE: Million Tonnes Of Oil Equivalent