Inflow and Outflow Rates Control in SAGD Wells: An Integrated Approach of Data-Driven and Physical-Based Analysis
Creators: Izadi, Hossein
Publisher: name: University of Alberta Library
Year: 2024

<p>The utilization of the Steam-Assisted Gravity Drainage (SAGD) method entails significant natural gas consumption and extensive water handling and treatment. The effective inflow and outflow rates control in producer and injector wells holds paramount importance. It serves multiple objectives, including the maximization of oil production, the enhancement of steam chamber development, and the reduction of the cumulative Steam Oil Ratio (cSOR), thereby minimizing freshwater usage. Flow Control Devices (FCDs) represent one of the technological solutions available to facilitate the control of the SAGD well’s inflow and outflow rates.<br>
Despite the broad utilization of different devices by operators to control inflow and outflow rates in SAGD projects, there is a notable absence of comprehensive and quantitative evaluations concerning the impact of flow rates control in real-world SAGD operations. Moreover, there has been limited exploration of flow rates control impact in various operational and subcooling conditions to enhance well performance, which implies increasing oil production while reducing freshwater consumption. Empirical relationships have been used in the FCDs numerical simulations, and the impact of reservoir heterogeneity on FCD’s performance has not been widely investigated. As a result, the development of efficient FCD design and evaluation remains a persistent challenge within the industry.<br>
This project combines physics-based modeling (numerical simulations) with data-driven modeling using real SAGD data to comprehensively evaluate the effects of inflow and outflow rates control in SAGD wells. Comparing real data analysis and simulation results will provide valuable insights into the significance of different flow rates control strategies.<br>
In the physics-based modeling approach, core analysis and Particle Size Distribution (PSD) data from several wells in Western Canada are collected. Permeability is estimated using PSDs based on a correlation we have developed using an optimization algorithm. The reservoir model is constructed using core analysis, PSD, and geology data, and the performance of different FCDs in different subcool scenarios is compared by assigning real flow-loop data to simulate FCDs responses. The primary benefit of incorporating flow-loop experiment data into the simulation lies in the creation of a mechanistic model based on physics rather than relying on empirical correlations. The findings revealed that by controlling the inflow rate, the creation of hot-spot regions could be prevented, and improved steam conformance was achieved through the management of both inflow and outflow rates. Additionally, the effective rates control led to an increase in oil production and a reduction in cSOR. The findings highlight the effectiveness of inflow and outflow rates control at various subcooling levels and their potential application in SAGD projects.<br>
In the data-driven modeling approach, we analyzed the impact of FCDs and lateral length of wells on SAGD well performance using data from major SAGD projects in Western Canada, spanning from 1997 to mid-2022. We utilized a normalization technique to evaluate the production history of wells, considering geological and operational parameters. The findings demonstrated that effective inflow and outflow rates control resulted in both increased oil production and reduced cSOR. Long-Short Term Memory (LSTM) Artificial Neural Networks (ANN) are also used to predict oil production and cSOR for the next 12 months for a new well to be drilled. The findings contribute to the optimization of SAGD operations and serve as a valuable guide for future Canadian SAGD well planning and decision-making strategy.<br>
What sets this process apart is its adaptation from a carefully labeled real database, providing valuable insights for decision-making in future SAGD pad developments aimed at reducing freshwater consumption and increasing oil production. Completion and production engineers can leverage these findings to enhance their understanding of relative production performance, ultimately leading to the development of more effective operational designs.</p>