|Theme||Visible||Selectable||Appearance||Zoom Range (now: 0)|
You must log in to edit PetroWiki. Content of PetroWiki is intended for personal use only and to supplement, not replace, engineering judgment. SPE disclaims any and all liability for your use of such content. A sharp, sometimes very high force and pressure load that is created when a valve is closed too rapidly in a flowing stream. The major force occurs behind the valve.
In this paper we investigate stability for severe slugging including self-lifting by using a stability solver. The stability solver is a tool in which a numerical linear stability analysis is applied to a mathematical model for a two-phase flow in a pipeline-riser system. The self-lifting approach is interesting because different configurations for the stationary state may occur. Depending on the system parameters, experiments show that two unstable regions may exist. Several parametric analyses are realized to evaluate the influence of self-lifting and to determine an optimal operational condition. Stability maps for severe slugging are built, and experimental data from literature are included, showing a very good agreement; in particular, the two unstable regions were satisfactorily predicted by the stability solver.
LI, Jun (State Key Laboratory of Exploitation and Utilization of Deep-sea Mineral Resources, Changsha Research Institute of Mining and Metallurgy Co Ltd.) | Tang, Hongping (State Key Laboratory of Exploitation and Utilization of Deep-sea Mineral Resources, Changsha Research Institute of Mining and Metallurgy Co Ltd.) | He, Cheng (State Key Laboratory of Exploitation and Utilization of Deep-sea Mineral Resources, Changsha Research Institute of Mining and Metallurgy Co Ltd.)
Using an in-house developed nodule collector designed for operating on the thin and soft sediment of the seabed, completed with track systems, hydraulic power system and travelling speed control system, no-load land-based experiments, no-load underwater experiments, and travelling experiments in a pool were performed; The data of the experiments were collected to analyze the track's dynamic parameters. The analysis results show that the mechanical resistance power accounts for a significant proportion (40.2%), the paddling resistance power being quite small (5.3%) and the output power (i.e. track transmission efficiency) is found to be 54.5%, which reflects the overall transmission efficiency of the track and can be used as an indicator for evaluating the characteristics of track transmission.
With the increasing demand for metal resources and the continuous depletion of terrestrial mineral resources, seabed mineral resources are becoming the alternative resources for human beings in the 21st century. Because these seabed mineral resources are found in deep sea, they are also referred to as deep sea mineral resources(Liu, Liu and Dai, 2014). Polymetallic nodules, one of these resources and of great importance, are rich in metal elements such as iron, manganese, nickel, and copper, and found in the seabed sediments of the world's oceans with a depth of 4500-6000m. The total reserve is estimated at 3 trillion tons(Ding, Gao,2006). Currently, the International Seabed Authority is stepping up the formulation of rules and regulations for the exploitation of seabed mineral resources, while countries around the world are also ramping up their research and development of deep-sea mining equipment.
The collecting system is the primary process in the whole polymetallic nodule mining system, and the collecting vehicle is the most important equipment in the entire system. During the "9th Five-Year Plan" period of China, it designed a prototype mining truck and conducted a comprehensive maneuver experiment under a water depth of 130 m at Fuxian Lake in Yunnan in 2001 to collect simulated polymetallic nodules. During the 12th Five-Year Plan period, Changsha Research Institute of Mining and Metallurgy developed the Kunlong 500 collector, and carried out a maneuver and collection experiment under a water depth of 500 meters in the South China Sea. During the 13th Five-Year Plan of China, National Key R&D Program is developing a 3,500-meter-level polymetallic nodule mining vehicle and plans to conduct a kilometer-level offshore test in the South China Sea. In other countries, a prototype of a tracked mining machine was developed by the Korean Maritime & Ocean Engineering Research Institute/KIOST in 2010 (Cho, Park and Choi, 2013), with a size of about 5%-10% of the commercial mining machine, the length, width and height being 5m×4m×3m, and the weight being about 9t. The Belgian GSR Program used the Patania II prototype in 2019 to conduct mining trials in polymetallic nodule mining areas (Global Sea Mineral Resource NV, 2018).
Johansen, Espen Sten (Techni Oilfield Products) | Fredheim, Dag Ketil (Equinor) | Huuse, Tom (Baker Hughes) | Volkers, Richard (Baker Hughes) | Hansen, Dag Almar (TECHNI) | Petersen, Christian (TECHNI)
In the drive for remote operations, reducing operator costs and reducing emissions and CO2, digitalization of sensors and control systems is imperative. To date, valves on wellheads and trees have predominantly been controlled by hydraulic actuators that are not ideally suited for fully remote operations.
A new, innovative, electric actuator has been developed under a Joint Industry Project (JIP) by Equinor, Baker Hughes and TECHNI. This actuator is designed for fail-safe, critical operations offshore and is subject to stringent safety design requirements. The key motivation is reducing CAPEX and OPEX for offshore installations, while increasing availability of wells while providing improved monitoring and condition based, predictive maintenance.
The electric actuator that was developed in the program has a patent pending fail-safe mechanism with extremely fast closing time (less than 1 second) to ensure well containment during critical situations. The actuator is designed to be a drop-in replacement for NoBolt™ CHA actuator solutions and is suitable for most standard wellhead and tree designs, sizes and pressure ratings. In the new all-electric design, a multitude of sensors in combination with an OPC-UA architecture, enables data-driven insights from the systems in operation.
The program was started in 2017 and has resulted in a system at Technology Readiness Level (TRL) 4 (on 0 to 7 scale) with TRL 5 testing planned in 2020 yielding it ready for field installation.
ADNOC Offshore started-up full field gas-lift activation for the first time in 2020. This major step will unlock field's potential by increasing reservoir withdrawal and increasing wells life by mitigating water production / breakthrough. This paper details the successful application of gas-lift from design during appraisal phase and early production stage to full field implementation. Fit for purpose design was implemented through multi-disciplinary studies and work. A strong change management in operating philosophy was requested to take onboard all stakeholders: Field development, Field Operation, Wells operation, Drilling and completion. Following appraisal and early production phases on a green field, wells design was optimized to ensure proper activation in most of the producers (two over three reservoirs developed). Due to full field development phasing, the first 30% of the wells completion were designed based on early production phase data. Before full field commissioning started, in well gas-lift valves were designed and installed, integrating all the dynamic information gathered during natural flow production. Valves change out was performed with the highest HSE standards, and taking into account full field development timing in order to reduce downtime and therefor maximize production. As gas-lift is new in the operating company, a strong change management was required: operating with gas-lift by field operation team, Completion design, Drilling and Gas-lift Production with SIMOPS. Gas Lift implementation will ensure the future oil production of the field as water injection and production will increase. Gas-lift practice implementation led to modifying the operating company's rules in multiple and deep aspects:
Improve field team competencies in handling high pressure gas-lift system, Increase completion and wells operation complexity, Implement new SIMOPS rules.
Improve field team competencies in handling high pressure gas-lift system,
Increase completion and wells operation complexity,
Implement new SIMOPS rules.
As a first achievement, one well under reservoir integrity issue (low productivity due to reservoir collapse) was re-activated and production of existing wells was increased of several thousands baril. Further increase in production is expected in the following months as implementation is deployed to all required wells.