Demulsifier Flow Control for Stable Water Separation in GOSP
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Accurately determining demulsifier dosage in Gas-Oil-Separation Plants (GOSP) is challenging due to variations in production, temperature, and oil properties, leading to either demulsifier waste or off-spec production if not optimized.
Innovation Solution
Implementing a real-time, field-based method that analyzes the response of separator trains to incremental demulsifier dosage changes, using a water separation profile (WSP) modeled with a 4-parameter logistic curve to adjust demulsifier flow rates based on current process conditions, thereby controlling water concentration entering dehydrators.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If demulsifier dosage is increased to ensure water separation, then water removal efficiency is improved, but demulsifier waste increases
Solution Approach 1:
The system uses real-time monitoring of water concentration at dehydrator inlets and feeds this information back to the demulsifier injection system. The control algorithm continuously adjusts demulsifier dosage based on actual separation performance, ensuring optimal dosage is applied without excess waste or insufficient treatment.
Solution Approach 2:
The demulsifier injection rate is made dynamically adjustable rather than fixed. The system continuously adapts the dosage based on changing crude oil properties, temperature, pressure, and water concentration measurements, allowing the process to respond to varying conditions and maintain optimal efficiency.
2Loss of substance
If demulsifier dosage is decreased to reduce waste, then demulsifier utilization is improved, but water separation efficiency deteriorates
Solution Approach 1:
Real-time water concentration measurements from dehydrator inlets provide feedback to the control system. When water separation efficiency drops, the system automatically increases demulsifier dosage to restore proper separation, preventing production upsets while minimizing unnecessary demulsifier use.
Solution Approach 2:
The system uses online sensors and real-time data to automatically monitor and adjust demulsifier dosage without manual intervention. The process self-regulates based on actual separation performance, ensuring water removal efficiency is maintained while optimizing demulsifier utilization.
3Loss of substance
If real-time control system is implemented to optimize demulsifier dosage, then demulsifier utilization is improved, but system complexity increases
Solution Approach 1:
The patent replaces manual demulsifier dosage adjustment with an automated control system that uses computer algorithms and online sensors. This substitution of mechanical/manual operations with automated electronic control simplifies the overall operation while achieving precise dosage optimization.
Solution Approach 2:
The control system automatically monitors water concentration, calculates optimal demulsifier dosage using embedded algorithms, and adjusts injection rates without human intervention. This self-service capability reduces operational complexity while maintaining precise control over demulsifier utilization.
4Device complexity
If manual demulsifier dosage adjustment is used, then system complexity is reduced, but water separation precision deteriorates
Solution Approach 1:
Online water concentration sensors provide continuous feedback to the control system, enabling precise monitoring of separation performance. This real-time data allows the system to make accurate adjustments to demulsifier dosage, achieving high water separation precision that cannot be obtained through manual adjustment.
Solution Approach 2:
The system replaces manual dosage adjustment with automated electronic control based on real-time sensor data and computational algorithms. This substitution enables precise control of demulsifier injection rates and water separation performance that exceeds the precision achievable through manual operations.
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 ensures stable water concentration at dehydrator inlets, minimizes dehydrator load, and optimizes demulsifier utilization by avoiding under- or over-estimation of demulsifier injection rates, thus preventing waste and production upsets.
Implementation Method 1
Demulsifier chemicals enhance the separation of the tight emulsion of salty water and oil according to specifications related to basic sediment and water content
Implementation Method 2
a high-pressure production trap (HPPT) that separates gas at pressures of 150-450 psig from the crude oil, a low-pressure production trap (LPPT) that separates gas at pressures around 50 psig from the crude oil
Data Source
AI summary
A computer-implemented method includes controlling water separation in a hydrocarbon stream flowing through a separator train including one or more separator vessels located upstream of a dehydrator by manipulating a demulsifier flowrate added to the separator train by: receiving data from a real-time process test of the separation train, estimating model fit parameters to the data to generate a water separation profile (WSP) correlating water draw-off and demulsifier flowrate for the separation train, determining a maximum and a minimum demulsifier flowrate from the WSP, receiving, from an operator, a separation performance for a target water separation value entering the dehydrator downstream from the separator train, and adjusting the demulsifier flowrate according to the WSP to achieve the target water separation entering the dehydrator.