Test Your Knowledge
PTL Quiz: Production Technical Limits
Instructions: Choose the best answer for each question.
1. Which of the following factors DOES NOT directly influence Production Technical Limits (PTL)?
a) Reservoir permeability
Answer
This is a direct factor.b) Wellbore diameter
Answer
This is a direct factor.c) Regulatory requirements
Answer
This can influence the chosen production rate, but not the technical limits.d) Oil viscosity
Answer
This is a direct factor.2. Understanding PTL is crucial for all of the following EXCEPT:
a) Determining the maximum sustainable production rate.
Answer
This is a core benefit of understanding PTL.b) Planning the location of surface facilities.
Answer
PTL informs the design and capacity of surface facilities.c) Estimating the remaining reserves in a field.
Answer
PTL is used in reserve estimation models.d) Predicting the outcome of political elections.
Answer
PTL is purely technical and does not relate to political matters.3. Which of the following methods is NOT commonly used to determine PTL?
a) Reservoir simulation using software.
Answer
This is a standard method.b) Conducting production tests to analyze well pressure response.
Answer
This is a key method for determining PTL.c) Using historical stock prices of oil companies.
Answer
Stock prices are influenced by many factors, not just PTL.d) Analyzing production decline curves to predict future behavior.
Answer
This is a critical aspect of PTL determination.4. What is the primary benefit of understanding PTL for a production company?
a) Reducing the cost of labor.
Answer
While PTL can impact production costs, this is not its primary benefit.b) Maximizing economic recovery from a field.
Answer
This is the primary benefit of understanding PTL.c) Minimizing the environmental impact of operations.
Answer
PTL helps optimize production, but environmental impact is a separate consideration.d) Ensuring the safety of all personnel on site.
Answer
Safety is crucial, but PTL primarily focuses on optimizing production.5. Which of the following statements BEST describes the role of Production Technical Limits (PTL)?
a) PTL is a fixed value that never changes.
Answer
PTL is dynamic and can change based on reservoir conditions and production strategies.b) PTL dictates the exact production rate that must be maintained.
Answer
PTL sets a limit, but production rates can be adjusted within that limit.c) PTL defines the maximum sustainable production rate under given technical constraints.
Answer
This accurately describes the role of PTL.d) PTL is primarily determined by the amount of investment made in the field.
Answer
Investment is a factor, but PTL is primarily determined by technical constraints.PTL Exercise
Scenario:
You are a reservoir engineer working on a new oil field. After initial exploration and drilling, you have gathered the following information:
- Reservoir permeability: 100 mD
- Oil viscosity: 20 cp
- Wellbore diameter: 6 inches
- Maximum surface processing capacity: 10,000 barrels per day (BOPD)
Task:
- Based on the available information, identify at least three potential factors that could limit the production technical limit (PTL) of the wells in this field. Explain your reasoning for each factor.
- Propose a strategy for determining the actual PTL of the wells in this field, considering the identified limiting factors.
Exercise Correction
Potential Limiting Factors:
- Reservoir Permeability: While 100 mD is a relatively good permeability, it might still be a limiting factor depending on the overall reservoir size and the presence of any low-permeability zones. Lower permeability can lead to slower fluid flow and limit the achievable production rate.
- Oil Viscosity: 20 cp is considered a high viscosity for oil. This can significantly hinder fluid flow and impact production rates.
- Surface Processing Capacity: The maximum surface processing capacity of 10,000 BOPD could limit production even if the reservoir and wellbore conditions allow for higher rates.
Strategy for Determining PTL:
- Reservoir Simulation: Develop a detailed reservoir model incorporating the known parameters and potential limiting factors (like permeability variations) to estimate the maximum production rate achievable.
- Well Testing: Conduct production tests on the wells to measure flow rates and analyze pressure response. This will provide real-time data on how the well performs under different production conditions.
- Production History Analysis: While limited in this case due to the new field, historical data from similar reservoirs or wells can provide valuable insights into expected decline rates and potential production limitations.
- Sensitivity Analysis: Perform sensitivity analysis on the reservoir model to understand how changes in various parameters (permeability, viscosity, wellbore diameter) affect the predicted PTL. This will help in identifying the most critical factors influencing production limitations.
