Subsea Choke Valve Control from Bottomhole Pressure Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solutions for controlling fluid pressure during injection into subterranean reservoirs fail to provide accurate pressure measurements and control at the reservoir level, leading to potential damage from over- or under-pressurization, as they only measure pressure before the fluid enters the well, not within the reservoir.
Innovation Solution
A system with subsea templates and pressure gauges at the bottom of drill holes measures actual reservoir pressure, using control commands to adjust fluid injection through choke valves based on pre-set rates and tolerances to maintain optimal pressure and flow rates, minimizing damage risks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If pressure measurement is performed before fluid enters the well, then pressure control can be implemented, but accurate reservoir pressure measurement is not achieved leading to potential damage
Solution Approach 1:
The patent places pressure measurement devices (pressure gauges) at the bottom of drill holes before fluid injection begins, enabling advance knowledge of reservoir pressure conditions. This preliminary measurement allows operators to assess whether reservoir pressure is within safe limits before initiating injection, preventing potential damage from overpressurization.
Solution Approach 2:
The system continuously monitors reservoir pressure through pressure gauges at the bottom of drill holes and uses this feedback information to control the injection process. The measured pressure data is transmitted to surface equipment where injection parameters are adjusted in real-time to maintain pressure within acceptable ranges, ensuring reservoir safety throughout the injection operation.
2Productivity
If fluid injection is performed without real-time pressure control at reservoir level, then injection efficiency is maintained, but pressure deviations cause potential damage to reservoir formations
Solution Approach 1:
The patent implements a closed-loop control system where pressure gauges continuously measure reservoir pressure at the bottom of drill holes, and this real-time feedback is used to adjust injection parameters. The system compares measured pressure against predetermined acceptable ranges and automatically modifies injection rate or pressure to maintain reservoir conditions within safe limits, preventing formation damage while sustaining efficient injection operations.
Solution Approach 2:
The injection system is designed to be dynamically adjustable based on real-time pressure measurements. Injection parameters such as flow rate and pressure are not fixed but can be continuously modified in response to changing reservoir conditions, allowing the system to adapt to pressure variations and maintain optimal injection efficiency while preventing harmful pressure deviations.
3Measurement precision
If multiple pressure measurement points are installed in the reservoir, then accurate pressure control is achieved, but system complexity and cost increase
Solution Approach 1:
The patent places pressure measurement devices at the most critical location - the bottom of drill holes where fluid enters the reservoir. This localized measurement approach focuses monitoring resources on the point of greatest importance for reservoir pressure control, achieving effective pressure management without the need for extensive measurement networks throughout the entire reservoir formation.
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
The system effectively controls pressure and flow within the reservoir, reducing the risk of damage by detecting and correcting pressure deviations in real-time, ensuring safe and efficient fluid injection.
Implementation Method 1
a first pressure gauge for each drill hole located at the bottom opening of the drill hole or near the bottom opening of the drill hole for measuring a bottom pressure of the drill hole
Implementation Method 2
The valve system has at least one choke valve on each of the at least two wells configured to control the injection of fluid into the subterranean void in response to received control commands
Implementation Method 3
controlling the injection of fluid into the subterranean void such that the bottom pressure does not deviate more than a first pre-set tolerance from a desired bottom pressure value
Data Source
AI summary
A fluid handling system, method, and computer-readable storage medium are presented for controlling the flow and injection pressure of fluid injected into a subterranean void at an offshore injection site for long term storage. A subsea template receives fluid from a fluid storage arranged on a seabed in connection with at least two well heads for at least two drill holes to the void. For each drill hole, a first pressure gauge at the bottom opening of the drill hole measures a bottom pressure, PB. The template comprises a utility system causing received fluid to be injected into the void and includes a valve system with a choke valve for each drill hole to control the injection of fluid into the void in response to control commands (Ccmd) based on a pre-set desired flow rate for each drill hole and a pre-set lowest allowable flow rate from the fluid storage.