c2

of 10
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Information Report
Category:

Documents

Published:

Views: 3 | Pages: 10

Extension: PDF | Download: 0

Share
Description
Description:
Tags
Transcript
  Well Performance Case Study - Oil Well Design An oil reservoir has been discovered in the North Sea. A vertical well has been drilled, a test stringinserted and flow characteristics measured. Fluid properties at stock tank and laboratory conditions have been obtained. Reservoir simulations have been performed to predict the change in watercut over the field life. The reservoir pressure will be maintained by water injection and the preference is to avoid the use of artificial lift methods. The engineer is asked to perform the following tasks: l Develop a blackoil model to match the laboratory data. It is necessary to develop a method of predicting the fluid physical properties so that the pressure losses and heat transfer characteristics can be calculated. l Develop a well inflow performance model applicable throughout field life. This provides a relationship between the reservoir pressure, the flowing bottom hole pressure and flowrate through the formation. l Select a suitable tubing size for the production string. l Engineering data. Task 1. Develop a Calibrated Blackoil Model No analysis work can be carried out until a blackoil fluid model has been developed. This allows all of the fluid physical properties to be estimated over the range of pressures and temperatures encountered by the fluid. These physical properties are subsequently used to determine the phases present, the flow regime, the pressure losses in single and multiphase flow regions, and the heat transferred to or from the surroundings. The following steps are to be carried out: l Obtain a partially calibrated blackoil model using the stock tank and bubble point properties. l Plot the partially calibrated oil formation volume factor (OFVF) over a range of pressures and temperatures to identify any differences between the measured and the predicted properties. Any discrepancies will lead to fluid flow modelling errors. l Apply calibration to the OFVF above the bubble point pressure and observe how the property curves are corrected. l Apply calibration to the OFVF below the bubble point pressure and observe how the property curves are corrected. l Apply calibration to the oil viscosity using first the measured dead oil data and then further tuning with live oil data. l Apply calibration to the gas viscosity and the gas compressibility. 1.After starting PIPESIM use the <File/new/well> menu to open a new well performance model and save this in your training directory (for example, c:\training\...). 2.Use the <Setup/blackoil...> menu to enter the stock tank oil properties and the bubble point properties given at the end of the case study. Help on the definitions and valid ranges of these stock tank properties can be obtained by selecting the button from the dialog header bar and clicking on the relevant data entry field. 3.Press the OK button and save the model. 4.Use the <Setup/blackoil/advanced calibration data>menu and press the plot PVT data... button. ( Note : do not enter the advanced calibration data at this stage). 5.Use the <Series> menu to plot the oil formation volume factor on the y axis. Page 1 of 10Well Performance Case Study -Oil Well Design06/06/2019mk:@MSITStore:C:\Program%20Files%20(x86)\Schlumberger\Pipesim\Programs\pipesi...  The following plot should be obtained:The partially calibrated curve for a temperature of 210 °F shows that the predicted OFVF is higher than the measured value both above and below the bubble point pressure. At 4,269 psia the predicted value is 1.52 compared to the measured value of 1.49 and at 2,000 psia the predicted value is 1.41 compared to the measured value of 1.38. Therefore further calibration is required. Calibration 1.Apply OFVF calibration above the bubble point pressure. The measured value is 1.49 @ 4,269 psia and 210 °F. The following plot should be obtained: Page 2 of 10Well Performance Case Study -Oil Well Design06/06/2019mk:@MSITStore:C:\Program%20Files%20(x86)\Schlumberger\Pipesim\Programs\pipesi...  2.Apply OFVF calibration below the bubble point pressure. The measured value is 1.38 @ 2,000 psia and 210 °F. The following plot should be obtained:Calibration of the oil viscosity requires two dead oil data points. The uncalibrated default approach is to use the Beggs and Robinson correlation which gives values of 1.561 cP @ Page 3 of 10Well Performance Case Study -Oil Well Design06/06/2019mk:@MSITStore:C:\Program%20Files%20(x86)\Schlumberger\Pipesim\Programs\pipesi...  200°F and 23.27 cP @°70°F. The Beggs and Robinson correlation uses the oil API gravity to predict two dead oil data points based upon data obtained from around 2,000 data points from 600 oil systems. 3.Plot the uncalibrated oil viscosity. The following plots should be obtained:In this case it can be seen that the predicted oil viscosity value at a temperature of 70°F and 14.7 psia is 23.27 cP as specified by the Beggs & Robinson correlation. This is significantly different from the measured dead oil data and would lead to errors in the prediction of pressure loss.4.Open the <Setup/blackoil/viscosity data>menu and select the correlation option user data . Enter the two measured values of 0.31 cP @ 200°F and 0.8 cP @ 70°F. The following plot should be obtained: Page 4 of 10Well Performance Case Study -Oil Well Design06/06/2019mk:@MSITStore:C:\Program%20Files%20(x86)\Schlumberger\Pipesim\Programs\pipesi...
Related Search
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks
SAVE OUR EARTH

We need your sign to support Project to invent "SMART AND CONTROLLABLE REFLECTIVE BALLOONS" to cover the Sun and Save Our Earth.

More details...

Sign Now!

We are very appreciated for your Prompt Action!

x