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Title: Subsea hydrocarbon sensor system

Abstract

A hydrocarbon detection system is provided for use in a subsea hydrocarbon production installation which includes production tree assemblies, an electro-hydraulic control module located on the sea floor and remote from the production trees, cable assemblies interconnecting the control module with the production trees through magnetic coupling devices. A pair of inductive elements are electrically coupled by the surrounding sea water. Displacement of the conductive sea water by escaping hydrocarbons affects the coupling between the inductive elements to produce a hydrocarbon-presence-responsive output signal. The inductive elements are resonated within a selected frequency range by capacitors coupled with a primary inductor coil by auxiliary windings on a common core element. An excitation signal sweeps over the selected frequency range at a rate effective to produce a peak detected signal at the resonant frequency. The peak output signal is then monitored to form a control signal functionally related to the presence or absence of hydrocarbons in the sea water.

Inventors:
;
Publication Date:
OSTI Identifier:
6148056
Patent Number(s):
US 4282487
Assignee:
TRW Inc IFI; EDB-82-003935
Resource Type:
Patent
Resource Relation:
Patent File Date: Filed date 26 Sep 1979
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; HYDROCARBONS; DETECTION; LEAKS; LEAK DETECTORS; DESIGN; COUPLING; ELECTRIC CABLES; ELECTRIC CONDUCTIVITY; FREQUENCY RANGE; OFFSHORE OPERATIONS; SEA BED; SEAWATER; SIGNALS; CABLES; CONDUCTOR DEVICES; ELECTRICAL EQUIPMENT; ELECTRICAL PROPERTIES; EQUIPMENT; HYDROGEN COMPOUNDS; ORGANIC COMPOUNDS; OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; WATER; 423000* - Engineering- Marine Engineering- (1980-)

Citation Formats

Marosko, R.J., and Warren, W.B. Subsea hydrocarbon sensor system. United States: N. p., 1981. Web.
Marosko, R.J., & Warren, W.B. Subsea hydrocarbon sensor system. United States.
Marosko, R.J., and Warren, W.B. 1981. "Subsea hydrocarbon sensor system". United States. doi:.
@article{osti_6148056,
title = {Subsea hydrocarbon sensor system},
author = {Marosko, R.J. and Warren, W.B.},
abstractNote = {A hydrocarbon detection system is provided for use in a subsea hydrocarbon production installation which includes production tree assemblies, an electro-hydraulic control module located on the sea floor and remote from the production trees, cable assemblies interconnecting the control module with the production trees through magnetic coupling devices. A pair of inductive elements are electrically coupled by the surrounding sea water. Displacement of the conductive sea water by escaping hydrocarbons affects the coupling between the inductive elements to produce a hydrocarbon-presence-responsive output signal. The inductive elements are resonated within a selected frequency range by capacitors coupled with a primary inductor coil by auxiliary windings on a common core element. An excitation signal sweeps over the selected frequency range at a rate effective to produce a peak detected signal at the resonant frequency. The peak output signal is then monitored to form a control signal functionally related to the presence or absence of hydrocarbons in the sea water.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1981,
month = 8
}
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  • A system for controlling, separating, processing and exporting well fluids produced from subsea hydrocarbon formations is disclosed. The subsea well tender system includes a surface buoy supporting one or more decks above the water surface for accommodating equipment to process oil, gas and water recovered from the subsea hydrocarbon formation. The surface buoy includes a surface-piercing central flotation column connected to one or more external floatation tanks located below the water surface. The surface buoy is secured to the seabed by one or more tendons which are anchored to a foundation with piles imbedded in the seabed. The system accommodatesmore » multiple versions on the surface buoy configuration.« less
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