Intermittent Lift or Flow

Test Your Knowledge

Intermittent Lift Quiz

Instructions: Choose the best answer for each question.

1. What is the primary advantage of intermittent lift over continuous gas lift?

a) Higher initial production rates b) Reduced gas consumption c) Increased wellbore pressure d) Lower risk of wellbore collapse

2. How does intermittent lift work to lift fluids to the surface?

a) By injecting a continuous stream of gas into the wellbore. b) By injecting gas periodically, creating pressure differentials. c) By using a pump to draw fluids upwards. d) By relying solely on natural reservoir pressure.

3. Which of the following is NOT a benefit of intermittent lift?

a) Improved wellbore stability b) Increased production rates c) Reduced environmental impact d) Increased risk of wellbore collapse

4. Intermittent lift is particularly beneficial for which type of wells?

a) Newly drilled wells with high production rates b) Mature wells with declining reservoir pressure c) Wells with a high concentration of dissolved gas d) Wells with a high concentration of hydrogen sulfide

5. How is the timing and volume of gas injection typically controlled in intermittent lift systems?

a) By manually adjusting valves at the wellhead b) By a surface-mounted system that monitors wellbore pressure c) By using a timer to control injection cycles d) By the rate of natural gas production from the well

Intermittent Lift Exercise

Scenario: A mature oil well is experiencing declining production due to reduced reservoir pressure. The well has a high water cut and low natural gas production. You are considering implementing an intermittent lift system to enhance production.

Task:

1. Explain how intermittent lift could help improve production in this specific scenario.
2. Identify two key factors that need to be considered when designing the intermittent lift system for this well.
3. Outline one potential challenge that could arise during the implementation of intermittent lift, and suggest a solution.

Techniques

Intermittent Lift: Optimizing Production with Periodic Gas Injection

This document will be broken down into five chapters:

Chapter 1: Techniques

Chapter 2: Models

Chapter 3: Software

Chapter 4: Best Practices

Chapter 5: Case Studies

Chapter 1: Techniques

1.1 Introduction to Intermittent Lift

Intermittent lift, also known as intermittent gas lift, is a well stimulation technique that involves injecting gas into the wellbore at periodic intervals. This contrasts with continuous gas lift, which injects gas constantly. By injecting gas intermittently, operators can optimize the amount of gas used and improve the overall efficiency of the lift process.

1.2 Types of Intermittent Lift Techniques:

Several different techniques can be employed for intermittent lift, each with its own advantages and disadvantages. These include:

• Pulse Injection: In pulse injection, short bursts of gas are injected into the wellbore, followed by a period of rest. This method is often used for wells with low production rates.
• Batch Injection: Batch injection involves injecting a larger volume of gas at regular intervals. This is suitable for wells with higher production rates or when a larger lift is required.
• Variable Injection: In variable injection, the amount and frequency of gas injection are adjusted based on real-time wellbore pressure readings. This approach provides greater control and flexibility over the lift process.

1.3 Implementation of Intermittent Lift:

The implementation of intermittent lift involves the following steps:

• Wellbore Evaluation: Determining the appropriate injection rate and frequency requires a thorough understanding of the wellbore geometry and reservoir conditions.
• Gas Injection System: Installing a gas injection system that can precisely control the timing and volume of gas injection is crucial for successful intermittent lift.
• Monitoring and Control: Continuously monitoring wellbore pressure and flow rates is essential to optimize the intermittent lift process and ensure it remains effective.

1.4 Benefits of Intermittent Lift:

• Reduced Gas Consumption: Intermittent lift can significantly reduce gas consumption compared to continuous gas lift, leading to lower operating costs and reduced environmental impact.
• Improved Wellbore Stability: By limiting the amount of gas injected, intermittent lift can help maintain wellbore stability, preventing potential damage to the wellbore.
• Increased Production Rates: The periodic nature of gas injection can lead to higher production rates compared to continuous gas lift, especially for wells with low production volumes.
• Flexibility and Adaptability: The ability to adjust the frequency and volume of gas injection provides flexibility to adapt to changing reservoir conditions and production needs.

Chapter 2: Models

2.1 Mathematical Models:

Mathematical models can be used to predict the performance of intermittent lift in different reservoir conditions. These models consider factors such as wellbore geometry, reservoir pressure, gas injection rates, and fluid properties.

2.2 Simulation Models:

Simulation models can be used to evaluate different intermittent lift techniques and optimize the injection parameters for specific well scenarios. These models can simulate the behavior of the wellbore and reservoir under different conditions.

2.3 Data Analysis:

Analyzing production data from wells utilizing intermittent lift can provide valuable insights into the effectiveness of the technique and allow for further optimization. This analysis can help identify trends and patterns in production behavior.

Chapter 3: Software

3.1 Intermittent Lift Software:

Several software packages are available specifically designed for simulating and optimizing intermittent lift operations. These software packages often incorporate mathematical and simulation models to provide detailed insights into well behavior.

3.2 Data Acquisition and Analysis:

Software tools are essential for acquiring and analyzing production data from wells employing intermittent lift. These tools enable operators to monitor well performance, optimize injection parameters, and identify potential issues.

3.3 Automation:

Software can be used to automate the control of gas injection systems, allowing for precise and efficient intermittent lift operation. This automation can enhance the reliability and efficiency of the lift process.

Chapter 4: Best Practices

4.1 Wellbore Evaluation:

Before implementing intermittent lift, conducting a comprehensive wellbore evaluation is crucial. This involves assessing wellbore geometry, reservoir conditions, and fluid properties to determine the optimal injection parameters.

4.2 System Design:

The design of the gas injection system should ensure precise control over the timing and volume of gas injection. The system should be reliable and capable of handling the required gas volumes.

4.3 Monitoring and Control:

Continuously monitoring wellbore pressure and flow rates is crucial to optimize the intermittent lift process. This monitoring allows for adjustments in injection parameters to maintain optimal lift performance.

4.4 Optimization:

Regularly reviewing and adjusting the intermittent lift process based on well performance data is essential for maximizing efficiency and production rates. This optimization process may involve adjusting injection parameters, optimizing gas usage, and identifying potential issues.

4.5 Environmental Considerations:

Operators should minimize the environmental impact of intermittent lift by ensuring responsible gas handling, minimizing emissions, and complying with relevant regulations.

Chapter 5: Case Studies

5.1 Case Study 1: Improved Production from a Mature Well:

This case study demonstrates how intermittent lift successfully increased production from a mature well with declining reservoir pressure. The application of intermittent lift allowed for the sustained extraction of valuable hydrocarbons that would have otherwise been lost.

5.2 Case Study 2: Optimizing Gas Consumption:

This case study highlights how intermittent lift significantly reduced gas consumption compared to continuous gas lift, resulting in substantial cost savings for the operator. The case study emphasizes the environmental and economic benefits of the technique.

5.3 Case Study 3: Adapting to Changing Reservoir Conditions:

This case study illustrates how intermittent lift can be adapted to changing reservoir conditions. The ability to adjust injection parameters in response to variations in reservoir pressure and fluid properties demonstrates the flexibility and adaptability of the technique.

By understanding the techniques, models, software, best practices, and case studies related to intermittent lift, operators can effectively optimize oil and gas production while reducing environmental impact and maximizing efficiency.