Dethiosulfovibrio peptidovorans gen. nov., sp. nov., a New Anaerobic, Slightly Halophilic, Thiosulfate-Reducing Bacterium from Corroding Offshore Oil Wells

Abstract Production decline caused by sand ingress was observed on 2 offshore oil wells in Brunei waters. Both wells were completed with a sub-horizontal openhole gravel pack and were subsequently shut in as the produced sand would likely cause damage to the surface facilities. In an offshore environment with limited workspace, crane capacity and wells with low reservoir pressures, it was decided to intervene the wells using a catenary coiled tubing (CT) vessel. The intervention required was to clean out the sand build up in the wells and install thru-tubing (TT) sand screens along the entire gravel packed screen section. Nitrified clean out was necessary due to low reservoir pressures while using a specialized jetting nozzle to optimize turbulence and lift along the deviated section. In addition, a knockout pot was utilized to filter and accommodate the large quantity of sand returned. The long sections of screens required could not be accommodated inside the PCE stack resulting in the need for the operation to be conducted as an open hole deployment using nippleless plug and fluid weight as well control barrier. A portable modular crane was also installed to assist the deployment of long screen sections prior to RIH with CT. Further challenges that needed to be addressed were the emergency measures. As the operation was to be conducted using the catenary system, the requirement for an emergency disconnect between the vessel and platform during the long cleanout operations and open hole deployment needed to be considered as a necessary contingency. Additional shear seal BOPs, and emergency deployment bars were also prepared to ensure that the operation could be conducted safely and successfully.

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Statistical models application for early fault detection in offshore oil wells

Rio Oil and Gas Expo and Conference ◽

10.48072/2525-7579.rog.2020.105 ◽

2020 ◽

Vol 20 (2020) ◽

pp. 105-106

Author(s):

Antonio Orestes de Salvo Castro ◽

Mayara de Jesus Rocha Santos ◽

Albino Lopes D'Almeida ◽

Geraldo de Souza Ferreira ◽

Gilson Brito Alves Lima ◽

...

Keyword(s):

Fault Detection ◽

Statistical Models ◽

Oil Wells ◽

Early Fault Detection ◽

Offshore Oil

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Geochemical Analysis of Hydrocarbons of Samples from eastern Offshore Oil Wells-Gaseous Hydrocarbons As a Measure of Oil and Gas Potential

10.4095/104699 ◽

1974 ◽

Author(s):

J D Leonard ◽

M A Rashid

Keyword(s):

Oil And Gas ◽

Oil Wells ◽

Geochemical Analysis ◽

Gaseous Hydrocarbons ◽

Gas Potential ◽

Offshore Oil

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Experimental Investigations of Offshore Sand Production Monitoring Based on the Analysis of Vibration in Response to Weak Shocks

Geofluids ◽

10.1155/2021/9953498 ◽

2021 ◽

Vol 2021 ◽

pp. 1-17

Author(s):

Yichen Li ◽

Gang Liu ◽

Zongwen Jia ◽

Min Qin ◽

Gang Wang ◽

...

Keyword(s):

Pipe Wall ◽

Oil Wells ◽

Impact Response ◽

Sand Production ◽

Time Frequency ◽

Response Characteristics ◽

Sand Particles ◽

Production Monitoring ◽

Offshore Oil ◽

The Impact

Sand production is a problem that is often encountered in unconventional oil and gas exploitation and that is difficult to effectively solve. Accurate online monitoring of sand production is one of the keys to ensuring the safety and long-term production of oil wells as well as efficient production throughout the life cycle of production wells. This paper proposes a method for monitoring sand production in offshore oil wells that is based on the vibration response characteristics of sand-carrying fluid flow impinging on the pipe wall. This method uses acceleration sensors to obtain the weak vibration response characteristics of sand particles impinging on the pipe wall on a two-dimensional time-frequency plane. The time-frequency parameters are further optimized, and the ability to identify weakly excited vibration signals of sand particles in the fluid stream is enhanced. The difference between the impact response of the sand particles and the impact response of the fluid flow to the pipe wall is identified, and corresponding indoor verification experiments are carried out. Under different sand contents, particle sizes, and flow rates (sand content 0-2‰, sand particle size 96-212 μm, and flow velocity 1-3 m/s), the impact response frequency of sand particles to the pipe wall exhibits good consistency. The characteristic frequency band of sand impacting the pipe wall is 30-50 kHz. A statistical method is used to establish the response law of the noise signal of the fluid. Based on this knowledge, a real-time calculation model of sand production in offshore oil wells is constructed, and the effectiveness of this model is verified. Finally, a field test is carried out with a self-developed sand production signal dynamic time-frequency response software system on 4 wells of an oil production platform in the Bohai Sea. This system can effectively distinguish sand-producing wells from non-sand-producing wells. The dynamic time-frequency response, field test results, and actual laboratory results are consistent, verifying the effectiveness of the method proposed in this paper and further providing a theory for improving the effectiveness of the sand production monitoring method under complex multiphase flow conditions. This study also provides technical guidance for the industrial application of sand production monitoring devices in offshore oil wells.

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Flow Instability Detection in Offshore Oil Wells with Multivariate Time Series Machine Learning Classifiers

10.1109/isie45552.2021.9576310 ◽

2021 ◽

Author(s):

Bruno Guilherme Carvalho ◽

Ricardo Emanuel Vaz Vargas ◽

Ricardo Menezes Salgado ◽

Celso Jose Munaro ◽

Flavio Miguel Varejao

Keyword(s):

Machine Learning ◽

Time Series ◽

Flow Instability ◽

Multivariate Time Series ◽

Oil Wells ◽

Machine Learning Classifiers ◽

Learning Classifiers ◽

Offshore Oil

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Old Oil Rigs Never Die

Mechanical Engineering ◽

10.1115/1.2019-nov2 ◽

2019 ◽

Vol 141 (11) ◽

pp. 36-41

Author(s):

Lina Zeldovich

Keyword(s):

Oil And Gas ◽

State Of The Art ◽

Oil Wells ◽

Engineering Project ◽

The World ◽

Offshore Oil And Gas ◽

Pumping Equipment ◽

Offshore Oil

Abstract Offshore oil and gas platforms are among the largest structures humanity has ever built. There are more than 7,500 of them towering up from seas all over the world, according to some recent estimates. As wells dry up and pumping equipment wears down, those structures are likely to become obsolete in the upcoming decades. Those oil wells will have be decommissioned and capped off and the platforms taken down. But taking down an offshore oil platform and the tower that supports it is no simple assignment. It is a massive engineering project that requires state-of-the-art equipment.

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