Subsea fluid sampling and analysis

Abstract

Subsea apparatus and a method for sampling and analysing fluid from a subsea fluid flowline proximate a subsea well is provided, wherein the apparatus comprises at least one housing located in close proximity to said subsea fluid flowline; at least one fluid sampling device located in the housing in fluid communication with a said subsea fluid flowline for obtaining a sample of fluid from the subsea fluid flowline; at least one fluid processing apparatus located in the housing in fluid communication with said subsea fluid flowline for receiving and processing a portion of the fluid flowing through said fluid flowline or in fluid communication with the fluid sampling device, for processing the sample of fluid obtained from the subsea fluid flowline for analysis, while keeping the sample of fluid at subsea conditions; a fluid analysis device located in the housing, the fluid analysis device being in fluid communication with the fluid processing device and/or with the fluid sampling device, the fluid analysis device being used for analysing said sample of fluid or the processed sample of fluid to generate data relating to a plurality of properties of said sample of fluid and communicating said data to a surface data processor or to at least one other subsea apparatus; and conveying means included in the housing for conveying the housing means from one subsea fluid flowline to another subsea fluid flowline or for conveying the housing to the surface.

Description

BACKGROUND OF THE INVENTION[0001]This invention relates to subsea apparatus for fluid sampling and / or analysis. In particular, the invention relates to a subsea apparatus for fluid sampling and / or analysis used in the oil and gas industry.[0002]Understanding the properties of fluids in wells in the oil and gas industry is critical for the assessment of oil or gas reservoirs. For example, the fluid properties may be used for the proper management of oil and gas reservoirs including for instance production management and flow assurance. Fluid sampling and / or analysis may be performed during various phases of the exploration, development and production phases of a reservoir. Conventional tools are able to take a fluid sample from the well and bring it to surface where it is processed and analysed. For example, often times the phase behavior of the fluid may be studied using an analysis known in the industry as PVT analysis which measures, inter alia, the bubble point of the fluid as we...

AI Technical Summary

Benefits of technology

[0045]FIGS. 11, 11a, 11b and 11c show schematic side view of a sampling bottle for low shock sampling with a piston inside the bottle of the subsea apparatus according to one embodiment of the invention;

[0046]FIGS. 12, 12a, 12b and 12c show schematic side view of a sampling bottle for low shock sampling without a piston inside the bottle of the subsea apparatus according to one embodiment of the invention;

Problems solved by technology

Sampling of the fluid at the surface is therefore not a suitable option for the correct estimation of the fluid phase behavior in subsea oil or gas wells.

However, the conditions prevalent in a subsea environment make access to a subsea fluid sample rather difficult.

This poses an additional complication in the sampling and analysis of subsea wells.

Also, the properties of the fluid produced by subsea wells may change significantly over a short period of time.

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