Wednesday, November 07
A common theme worldwide in the production of gas fields is the eventual requirement to deliquify the wells. Depending on depth and location, many successes and challenges are encountered. This session looks at field cases to document industry best practices, fundamentals and applications for gas well deliquification leading to optimal field development. We invite stories covering the widest variety of measures ranging from the most common (automated intermittent production, surface compression and velocity string) and the well specific (foam-assisted lift, plunger lift) to the most advanced (gas lift, downhole pumping).
0930 - 1000: Sharing Experience of 100 Velocity String Installations and 10 Foam-assisted Lift Field Trials in The Sultanate of Oman by Ahmed Al-Hashami, PDO
1000 - 1030: Dual Shot Acoustic Technique to Troubleshoot Gas-Lift Wells by Carrie Anne Taylor, Echometer
1030 - 1100: Barnett Gas Shale Deliquification Management: Current Strategy and Further Optimization by Jacques Danquigny, Total
Production wells in gas reservoirs with an active aquifer are vulnerable to liquid loading issues as the gas-water contact rises with depleting reservoir pressure and ultimately reaches the well. Horizontal wells pose their own set of problems related to the geometry of the wellbore in the reservoir section, where the water breakthrough can occur simultaneously from multiple sections along the wellbore. This leaves few options of deploying deliquification remediations. For example, water shut-off at the deeper perforations as it is normally practiced in vertical wells is not applicable in horizontal wells; and batch foam treatments may have difficulty reaching the perforations due to the well deviation. Moreover, the performance of transporting gas and liquid in the undulating horizontal wellbore followed by the horizontal-vertical transition with changing flow regimes is more difficult to predict than for vertical wells, particularly for liquid loading and wellbore slugging under continuous wellbore and near-wellbore flow interactions.
With the drilling of more horizontal wells with both trajectory and completion complexity as well as multiple reservoir-segment contact, well flow dynamics are increasingly becoming a challenge for operators. This session is therefore dedicated to the discussion of horizontal wells with the aim of sharing experience gained in predicting and mitigating liquid breakthrough, accumulation, loading and slugging under both normal production and shut-in/start-up with/without artificial lift.
1130 - 1152: Using Dynamic Simulation to Diagnose the Startup Failure of a North Sea Long Horizontal Oil Well with Gas-breakthrough by Bin Hu, Kongsberg Digital
1152 - 1214: Gas-lifting a Liquid Loaded Gas Well with Fluid Loss Control Valve by Quirinius van Dorp, Dana Petroleum
1214 - 1236: Foam Assisted Gas Lift: the impact of different surfactant delivery methods on oil well performance by Marco Marino, NAM
1236 - 1300: Liquid loading behavior in concentric and eccentric annuli - Pressure drop, hold-up and film thickness measurements in annulus flow by Stefan Belfroid, TNO
The optimisation of recovery and production from mature fields is an integrated effort that covers several disciplines. One of these is process and production facilities engineering.
The responsibility of production engineers is to optimize and maintain the functionalities of the production facilities. This includes well heads, flowlines, separators, gas drying, etc. etc.
Within a full system approach well optimisation could unlock topside scenarios bringing higher overall recovery of the full field, changing former classical back-out scenarios into new overall production opportunities.
Also metering is one of the most essential elements that allows teams to understand the system performance and identify opportunities for optimisation. Especially in production operations, the monitoring, analysis and identification of challenges or opportunities is a contribution to tail end production operations. In this session, we invite attendees to share their best practices and technologies to optimize top site operations and demonstrate how it plays an essential role in asset management.
1400 - 1430: Produce The Limit – Topside Optimisation by Mike Gunningham, SGS Subsurface Consultancy
1430 - 1500: Field life extension by production integration by John van Miert, Total
1500 - 1530: Innovative Approach to Production Optimization through Integrated Teams by Suzanne Klaassen, Neptune
Production from mature oil and gas wells due to complexities in operations and marginal operational benefits is challenging. Underperforming production can result by e.g. decline in reservoir pressure, liquid loading in gas wells, scaling and have a huge impact on the expected well deliverability and overall field performance.
Early prediction of production alterations and proactive actions to control or mitigate these issues is key for successful day to day operations. Additionally, considerable amounts of data are generated during the development, testing and operation of these assets which contains valuable information and insights. In the recent years, the application of machine learning, artificial intelligence and big data for extracting information and insights from the data (historical and real-time, structured and unstructured, etc.) received attentions in the oil and gas industry.
The goal of this session is to provide data-driven insights for monitoring, predictions and optimising the production and performance of mature assets. The topics related to this session are (but not limited to);
- Case studies, field cases, challenges, successes and failures
- Digital Oil field and Real time Production Monitoring
- Application of “Big Data”, artificial intelligence and machine learning
- Descriptive, predictive and prescriptive analytics
- Data mining and data-driven models
- Hybrid analytics
- Added value of data visualisation
1600 - 1618: On Back-Allocation through Machine Learning by Iulian Dobrovolschi, Pejman Shoeibi Omrani, Stefan Belfroid, TNO
1618 - 1636: Artificial Neural Networks (ANN) applied to decline analysis and production forecasting by Esteban Muñoz, Adrian Vecchia, Iulian Dobrovolschi, Pejman Shoeibi Omrani, Wintershall, TNO
1636 - 1654: Superposition & transient modelling approach for a tight oil reservoir by Vitaly Elichev, Wintershall
1654 - 1712: Platform decomplexing in a mature asset by Eva Grimbergen, Shell
1712 - 1800: Short-Term Integrated Production Optimization by Arnaud Hoffmann, Tieto Oil & Gas
Thursday, November 08
Towards the end of the life of a well/field, not only the production and lifting of water poses a problem. An increase of water might also mean a higher load of ions that could form scale like BaSO4, CaSO4, CaCO3 and cause medium to severe production problems from the reservoir near wellbore up to the X-mas tree.
The increase of liquids also increases the risk of corrosion throughout the well
Moreover, at the decreasing reservoir pressure the evaporation of water in the gas phase increases and could result in Salt drop out near the wellbore that will hamper the gas stream.
This session is intended (but not limited) to share experiences and results of different mitigation measures for the three mentioned challenges; salt precipitation, various kinds of scale and corrosion.
Also, we would like to discuss the interaction of the various mitigation methods especially how these could adversely affect each other e.g. foamers could wash corrosion inhibitors from the tubing surface. Since production optimisation in mature gas assets requires integration of all parties and disciplines, we should ask ourselves how can we stimulate cross-discipline communication.
0930 - 1000: Halite Scale Surveillance and Mitigation in Sultanate of Oman by Ahmed Hashami, PDO
1000 - 1030: Restore productivity at tail end phase – challenges and field cases by Christoph Kersten, Dea-group
1030 - 1100: Application of foam assistant sand clean out in a Subsea well environment by Patricia Seibold, Wintershall
In mature fields, low pressure wells often suffer from multiple problems, ranging from ‘normal’ liquid loading to scaling problems or for instance HUD fill causing inflow deterioration, accelerating the onset of liquid loading. In such wells, it quickly becomes a dilemma what to do when an intervention is needed.
Restoring damaged inflow from scaling, for instance, requires liquids to be pumped into the well to dissolve the solids, but the well often cannot unload the liquids without artificial help. Limiting the treatment volumes is usually the first step, but may not always be sufficient. Lifting in the well after the treatment using coiled tubing and nitrogen can be a time- and money-consuming ordeal with no guaranteed outcome. Adding foamer to the stimulation mix has seen promising results but is not widely adopted in the industry. Cleaning out a HUD fill also poses challenges that are not easy to overcome. Stirring up or even milling the HUD with coiled tubing is limited in low pressure wells, since the well does not have sufficient pressure to assist in lifting out the solids and the necessary (nitrified) fluids. The risk of losing fluids and killing the well for a long time is always present. Bailing the HUD with wireline or E-line is an option but is often hampered by the combination of a large casing and a small ID tubing, so many runs are needed to lower the HUD.
In this session, we will be looking at an overview of the current state of the art of low pressure well intervention, common pitfalls, and what could be done about them.
1130 - 1200: Concentric Coiled Tubing Clean Out of a Low-pressure Offshore Gas Well - Babak Ghaempanah, NAM
1200 - 1230: A Simplified and Low-Cost Acid Stimulation Methodology of Low-Pressure Gas Wells - Tony Robertson, NAM
Surfactants, also often referred to as foamers, are being increasingly used to optimize production in oil and gas assets. Most applications relate to improvements of outflow performance of gas wells by reducing the minimum velocity and rate at which liquids can be successfully produced to surface, thereby increasing the recovery factor of the field. Some emerging applications are instead found in gas lifted oil wells, whereby the efficiency of the gas lift system is enhanced by foam assisted lift. Promising results have been recorded in several assets, especially in those cases where wells flowing in slug regime could be stabilized. Finally, topside applications are also showing promising results, with foamers used to reduce hold-up in pipelines or act as flowing pigs.
This session will explore different applications of surfactants in both oil and gas assets, and for both downhole and topside cases.
1330-1400: Effect of salinity and thermal ageing on the performance of foamers for gas well deliquification by Pejman Shoeibi Omrani, A. Greidanus; TNO & TUDelft
1400-1430: Downhole foamer injection via gas lift: laboratory and field challenges by Alessandro Allegrucci, Ernesto Petteruti; Chimec
1430-1500: Black Oil foamer to optimized the Gas Lift production wells by Francesco Pitassi, Lucio Ciavarro, Filiberto Placca; BakerHughes
1500-1530: Void fraction estimation for aqueous foam flows in a horizontal pipe for dewatering applications. by Igor Matteo Carrareto; ENI