Bottom-up Gravity-assisted Pressure Drive for Heavy Oil Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional hydrocarbon extraction methods face challenges such as restricted fluid mobility, limited reservoir contact, inefficient energy use, and thermal energy loss, particularly in unconventional oil reservoirs like bitumen and heavy oils, where processes like Steam Assisted Gravity Drainage (SAGD) struggle with early steam chamber spread and heat loss to the overburden.
Innovation Solution
Drilling multiple wells near the reservoir bottom to create high-mobility zones and forming a flat stimulant chamber, utilizing a combination of gravity drainage and pressure drive mechanisms to ensure uniform stimulant distribution and oil drainage, thereby optimizing stimulation and drive energy from the initial stages of production.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If Steam Assisted Gravity Drainage (SAGD) is used to produce heavy oil from unconventional reservoirs, then gravity-driven drainage enables continuous production, but the steam chamber spreads early to the reservoir top causing thermal energy loss to the overburden
Solution Approach 1:
The patent applies preliminary action by first creating high-mobility zones and injecting stimulants to reduce viscosity before initiating full-scale production. This preliminary stimulation phase prepares the reservoir to channel flow along the bottom, preventing early steam chamber spread to the top and reducing thermal energy loss to the overburden while maintaining continuous production capability
2Ease of operation
If conventional steam flooding is used to reduce viscosity of heavy oil, then mobility of hydrocarbon liquid is improved, but fluid mobility becomes restricted at the flooding front where phases are mixed
Solution Approach 1:
The patent segments the reservoir into distinct zones: a high-mobility zone along the bottom where stimulants are injected and viscosity is reduced, and an overlying zone where gravity drainage occurs. This segmentation prevents mixing of phases at a single front, maintaining fluid mobility by keeping the stimulated zone separate from the drainage zone
Solution Approach 2:
The patent transitions from traditional vertical steam flooding to a bottom-up approach, injecting stimulants along the bottom of the reservoir and draining upward through multiple wells. This dimensional change in flow direction eliminates the flooding front restriction problem by creating separate injection and production zones at different vertical levels
3Area of stationary object
If multiple wells are drilled to increase reservoir contact area, then stimulation coverage is improved, but cost and complexity of the operation increase
Solution Approach 1:
The patent makes each well multi-functional by configuring them to serve both as injection wells and production wells at different stages and locations. The bottom-up approach allows wells to inject stimulants, produce hydrocarbons, and facilitate gravity drainage, reducing the total number of wells needed while maintaining extensive reservoir contact area
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances reservoir contact, increases energy efficiency, reduces heat loss, and achieves faster and more complete hydrocarbon recovery with improved thermal efficiency and reduced mechanical impact on the caprock.
Implementation Method 1
the drive energy is gravity
Implementation Method 2
due to the density difference between the various phases
Implementation Method 3
the driving energy is the pressure difference between the injection and production wells
Implementation Method 4
viscosity of the in-situ heavy oil or bitumen is reduced through injection of steam, solvent or whatever other materials
Data Source
AI summary
A method is taught for producing hydrocarbons from a reservoir by drilling two or more wells located proximal a bottom of said reservoir. The method comprises initiating one or more high-mobility zones connecting said wells along the bottom of the reservoir and producing the reservoir from the bottom of said reservoir upwards.