Tuesday, June 19
A principal challenge that we face in our industry today is not only to replenish reserves but to increase hydrocarbon production and recovery from an existing asset base of mature fields with ageing facilities. Today, the key to economic mature field production and (where justifiable) redevelopment is accurate predictive capability of the wells and fields and mitigation of uncertainties that lead to failure to produce. New and updated industry regulations are widening the scope of well integrity as a tool to achieve this with the result that we are experiencing a shift towards more detailed monitoring and controlling of each individual aspect of the well life cycle.
Current low oil and gas prices continue to challenge the economics of aging and mature assets production and we are being tasked to push the boundary of the design life of wells while still operating in a safe, efficient and controlled manner. Applying new (and often costly) well integrity principals and techniques to wells which were designed before most of us were born can have limited efficiencies in cases where workover cannot be justified.
This session will address a case history of such challenges and how advances and current practices have delivered improvements in productive efficiency through implementation of technologies that are used to optimize extraction within production systems. The session will further explore and discuss how the industry is managing aging wells with newly available tools: Leak detection tool, alternative P&A techniques, machine learning, statistical failure model.
Subsequently, we will challenge the current tools on their applicability for old wells:
- Are legacy Cement Bond Log data suited for evaluating cement placed in-situ 50 years ago? How can we consider it valid over decades of operations?
- Explore how the reconversion of old well is handled, how their lifetime is extended.
- Explore how risk assessment is approached when dealing with high uncertainty: wells constructed several decades ago where documentation is limited, degraded or non-existent.
Cost-effective management of Well Integrity, in combination with a toolbox of information and technologies, is key to providing the necessary information to operators to make critical decisions which will optimise workover resources, cost, time and associated production outages and results in maximizing our well potential.
The purpose of this session is to discuss the methods of detection of well integrity issues using both classical methods – like CBL and also new emerging technologies like acoustic detection. Methods of detection will be discussed and commented function on their impact in identifying actual integrity problems and possible future problems.
Also the reliability of different technical solution will be debated based on the experience of the participants. Technical solutions are split in two groups: technologies for detection and technology for remedial action. Participants are encouraged to share the practical experience they have and also to share the case histories which can be very relevant and can prove reliability of certain technologies.
Emerging technologies are considered the new technologies that are coming on the market as answer of industry needs for detection and remedial action upon well integrity issues. Discussion and debate will start from technology needs- different participants with different field experience will present the industry needs as it is perception in their working environment. Common problems are identified and for these identified problems will be discussed the existing new technologies that can be in different status of maturity like follows: technologies still in R&D status, technologies for which exists pilot tests but they are not commercial yet and technologies which are mature and ready to implement.
The ever increasing challenge faced by oil and gas field operators of lost or deferred production due to tubing \ casing failure in mature wells, together with the associated significant remediation costs has driven the need for a robust approach to extension of life-of-well operations.
The session will focus on how using a combination of modelling (with the input of multiple production parameters) and direct measurement of the corrosion rates, it is possible to confidently estimate the life of the completion in relation to the rate of corrosion before expected failure. Costs can therefore be saved by avoiding unexpected production deferral and planning workovers optimally. This session will also explore case histories of some of the predictive software solutions available.
Correct materials selection of all component parts of a well is a critical aspect of the integrity of a well and is fundamental to successful well integrity through the operational phase. The well design (including tubular strength requirements) and intended operation (routine and incidental environments in contact with well components) are key inputs in selecting materials suitable for the full well life cycle. Corrosion monitoring in oil fields can be performed with corrosion probes, analysis of fluids from the well, and various downhole inspection technologies.
A well failure model/matrix approach is often used in Well Integrity management to identify the most common modes of well failure and to optimise associated action plans and response periods.
Because all wells are exposed to different operating conditions, it is important to recognise that a well failure model is designed to streamline the risk assessment process and not replace it. This session will discuss some of the different failure models implemented by the industry to manage well integrity, and the strengths and weaknesses of these different models.
In developing well failure models it is also necessary to consider the model in relation to well barrier envelopes and associated leak paths. The session will show how some operators have improved and simplified their risk assessment process by looking at their model in terms of barriers, rather than individual well components. The session will also focus on how a real time well failure model plays a critical role in effective well integrity risk management.
Wednesday, June 20
The legacy of existing plugged and abandoned wells and the abandoned wells (not plugged) is growing globally, plug & abandonment plans are being created for the most environmentally sensitive areas like offshore but many onshore wells are left unattended. The public awareness on the risk associated with seepage or leakage of the abandoned or plugged and abandoned wells is growing, several surveys & studies on methane emissions from abandoned wells are evident. The cost and technology to provide well integrity assurance through monitoring or surveillance is a challenge with respect to ownership and responsibility. On the other hand new developments are initiated with alternative concepts and materials. One alternative with cost saving opportunities for P&A and zonal isolation is through natural sealing or with use of natural formation materials. Another development is looking at re-using wells being tertiary O&G recovery or for sustainable energy solutions like CO2 storage or geothermal solutions. The life cycle assessment and understanding the well integrity barrier requirements enter a new era of understanding the well integrity subsurface issues and the associated risk, but also the opportunities that become evident when understanding the integrity status.
This session discusses:
5.1. Challenges related to well integrity after 100 + years production
The opportunities and challenges on new materials and natural sealing, how to speed up evaluation of new developments. The oil and gas industry legacy of number of wells drilled versus the amount active operated and number of wells left idle is receiving growing attention. The need for long term durable plugging solutions for abandonment seems to be in contradiction to the need to reduce costs and prohibit future re-entries. There is a need for field test opportunities and challenges on natural sealing to restore integrity for re-use or P&A
5.2. Well barrier envelope for abandoned and suspended wells
The method of well integrity barrier assessment, is generally recognized in the industry that +/- 45 % of existing wells have known annular pressures. This is a clear indication that sealing wells is a demanding task. Currently the same cement and steel base materials are used for P&A as are used as for constructing a well. The long term sealing reliability is hard to proof since steel is receptive to corrosion and cement is brittle of nature and not compliant to subsurface movement natural occurring over hundreds of years. Assessing the well barriers is therefore a challenge, what does qualify as a barrier and how should you go about the risk assessment.
5.3. Alternative approaches of the end of well life: CO2 storage for O&G tertiary recovery etc.
The assessment methods and technologies for re-use opportunities are expanding being tertiary O&G recovery or for sustainable energy solutions like CO2 storage or geothermal solutions. The life cycle assessment and understanding the well integrity barrier requirements enter a new era of understanding the well integrity subsurface issues and the associated risk, but also the opportunities that become evident when understanding the integrity status.
Many of the loss of well integrity events have been attributable to “Human Factors” and specifically the inability to recognize hazards or deviations.
The inclusion of human factors mitigation into “well control” came following the Macondo disaster. Aptly termed “Well Operations Crew Resource Management” (WOCRM) the concept is equally applied to the entire “well integrity” discipline to enhance the cognitive abilities of engineering and operational teams.
“Human Factors” refers to technological, organizational and job factors as well as human characteristics that affect how people assess a situation, take a decision and execute a task. It includes the competence and behavior of personnel, the design and functionality of equipment, and organizational structure and support.
This workshop session will explore the diverse challenges faced in managing well integrity often involving different stakeholders across each phase of the well life cycle. How can we learn from other industries e.g. aviation and nuclear in applying “Human Factors” to improve performance? Workshop participants will discuss human factor mitigation initiatives to improve well integrity decision making.