Fail-safe subsea fluid transportation system

Abstract

This specification discloses a subsea system for the production of fluid minerals. The system includes a product gathering network provided with production satellites in which the gas-oil-water ratios of each well are periodically tested and the flow rates are automatically controlled. A power distribution network connects a central power station, either floating or bottom supported, at the site or on land nearby, with the various satellite stations and submerged wellhead units. Provision is made for entry into the satellites and diver maintenance at the submerged wellheads. A rigid transportation pipe transports produced fluids to the water surface. At the lower end of the rigid transportation pipe is a designed break-away section which will be broken if excessive strain is encountered. An inverted funnel is located over the break-away section to trap any escaping fluid.

What is claimed is: 
     
       1. A fluid transportation path for conveying fluids upward through a body of water, comprising: a rigid fluid transportation pipe adapted to be substantially vertically located in a body of water, said rigid transportation pipe adapted to terminate at a first end thereof, above the surface of the body of water, said rigid transportation pipe adapted to terminate at a second end thereof, far beneath the surface of a body of water, in an inverted funnel, conduit means adapted to direct fluid into said second end of said rigid transportation pipe from a source of fluid, far beneath the surface of a body of water, a section of said conduit means within said inverted funnel being the weakest point in said fluid transportation path whereby, if a rupture should occur in said fluid transportation path, it would occur within said funnel and a minimum amount of produced fluid would be lost into the surrounding body of water. 
     
     
       2. A fluid transportation path for conveying fluids upward through a body of water as recited in claim 1 wherein said conduit means adapted to direct fluid into said second end of said rigid transportation pipe from a source of fluid beneath the surface of a body of water is a flexible transportation line connected to said rigid transportation pipe within said inverted funnel. 
     
     
       3. A fluid transportation path for conveying fluids upward through a body of water as recited in claim 2 wherein said rigid transportation pipe terminates at the first end thereof in a fluid storage tank adapted to float at the surface of a body of water. 
     
     
       4. A fluid transportation path for conveying fluids upward through a body of water as recited in claim 3 wherein there are means for mooring a tanker to said storage tank and means for offloading stored fluids from said storage tank into said tanker. 
     
     
       5. A subsea system for the production of fluid minerals from subaqueous deposits through wells having wellheads located beneath the surface of a body of water, comprising: a plurality of underwater wellhead units, each of said wellheads of said wellhead units being equipped with at least one remotely actuatable valve for controlling the flow of produced fluid from the respective well; at least one production satellite station located beneath the surface of said body of water; flowlines supported over at least a portion of their lengths on said marine bottom, connecting each of said plurality of underwater wellheads, through the respective remotely actuatable wellhead valve, with the interior of said satellite station; means within said satellite station for combining the produced fluid from all of said wells flowing through said flowlines and directing said produced fluid through a main outlet line; means within said satellite station for selectively testing said produced fluid flowing through each of said flowlines individually; means for actuating said remotely actuatable wellhead valves in response to the results of the selective testing of the produced fluid flowing through said flowlines to optimize production; and fluid pump means connected between said main outlet line, a fluid transportation path extending to a storage tank on the surface of the body of water for storing the fluid minerals produced in said subsea system; said fluid transportation path having a rigid fluid transportation pipe depending substantially vertically from said storage tank and terminating just above said marine bottom in an inverted funnel and a flexible transportation line extending between said funnel and the outlet of said pump means; and a section of said flexible transportation line, within said funnel, being the weakest point in said fluid transportation path whereby, if a rupture should occur in said fluid transportation path, it would occur within said funnel and a minimum amount of produced fluid would be lost into the surrounding body of water. 
     
     
       6. In the subsea production system of claim 5, pressure actuated switch means for shutting off said pump means in response to abnormal pressures in said fluid transportation path indicating a rupture in said fluid transportation path. .Iadd.7. A method of recovering a fluid such as oil or the like escaping from a crack in a flowline or the like submerged in a body of water, the method comprising: locating a fluid containing container over and adjacent said crack;   passing at least some of the fluid trapped within said container upwardly through a conduit to the surface of the water; and   disposing of the fluid at the surface of the water. .Iaddend. .Iadd.8. A system for recovering a fluid such as oil or the like from a leaking underwater source comprising:   a chamber completely submerged in the water and positioned adjacent to and over the leaking source, said chamber being open at its lower end;   a conduit in fluid communication with the interior of said chamber and extending to a position adjacent the surface of the water; and   means attached to said conduit at said position adjacent said surface of said water for disposing of any leaking fluid which passes through said conduit. .Iaddend..Iadd.9. The system of claim 8 wherein said means for disposing of said fluid comprises:   a floating storage means.