US-12623862-B2 - Pumping system and method

US12623862B2US 12623862 B2US12623862 B2US 12623862B2US-12623862-B2

Abstract

A pumping system for moving a liquid, or a mixture of a liquid and one or more objects, from a collector device submerged in a body of water, to a receiving facility includes a first delivery line, a second delivery line and a pump unit. The pump unit is submerged in the body of water at a first depth below the water surface and arranged between the collector and the receiving facility. The first delivery line is fluidly connected between the collector device and a pump unit inlet. The second delivery line is fluidly connected between a pump unit outlet and the receiving facility. The collector device is arranged at a second depth and the first depth and the second depth are controllable independently of each other.

Inventors

Magne Hystad

Assignees

KARMØY WINCH AS

Dates

Publication Date: 20260512
Application Date: 20240711
Priority Date: 20170324

Claims (20)

1 . A pumping system for moving a liquid, or a mixture of a liquid and one or more objects, comprising a surface vessel or structure, a pump unit, and a collector device, and a first delivery line connected between the collector device and the pump unit and a second delivery line connected between the pump unit and the surface vessel or structure; wherein the pump unit is operable for moving said liquid, or mixture of a liquid and one or more objects, from the collector device to a receiving facility arranged on the surface vessel or structure; wherein the pump unit is supported and controlled by the surface vessel or structure via a first support-and-control apparatus and operable to be arranged at a first depth below a surface of a body of water, between the collector device and the surface vessel or structure; wherein the collector device is operable to be arranged at a second depth below said a surface of a body of water; wherein the pump unit is configured to generate suction in the first delivery line and a positive pressure in the second delivery line; wherein the first depth and the second depth are controllable independently of each other.
2 . The pumping system of claim 1 , wherein the collector device is operable to be arranged in the body of water and/or on a seabed below the body of water, and supported and controlled by the surface vessel or structure via a second support-and-control apparatus.
3 . The pumping system of claim 1 , wherein the first support-and-control apparatus comprises a towing wire connected between the pump unit and the surface vessel or structure.
4 . The pumping system of claim 1 , wherein the first support-and-control apparatus comprises a carrier arm or a lifting wire connected between the pump unit and the surface vessel or structure.
5 . The pumping system of claim 1 , wherein the pump unit is connected to outriggers on the surface vessel or structure or to telescopic arms or other structures that allow the pump unit to be lowered below the water surface.
6 . The pumping system of claim 1 , wherein the pump unit is arranged in a tank inside the surface vessel or structure, and the tank is open to the surrounding sea below the surface vessel or structure.
7 . The pumping system of claim 2 , wherein the collector device is a trawl and the second support-and-control apparatus is a trawl wire.
8 . The pumping system of claim 1 , wherein the pump unit comprises a pump selected from the group consisting of a centrifugal pump, a positive displacement pump, and any pump which imparts mechanical energy to said liquid.
9 . The pumping system of claim 1 , wherein the receiving facility is arranged at a height above the water surface.
10 . The pumping system of claim 1 , further comprising a valve fluidly connected to the first delivery line at an inlet in the vicinity of the pump unit and operable to allow an inflow of ambient seawater into the first delivery line.
11 . The pumping system of claim 10 , wherein the valve is a check valve.
12 . The pumping system of claim 10 , wherein the valve is manually or automatically operated, or set to open and close at one or more predetermined pressures.
13 . The pumping system of claim 12 , wherein the valve is an adjustable valve.
14 . The pumping system of claim 1 , wherein the pump unit comprises a housing shaped to reduce hydrodynamic drag.
15 . The pumping system of claim 1 , wherein the pump unit comprises one or more weights.
16 . The pumping system of claim 1 , wherein the pump unit further comprises a depth rudder configured and operable to imparting a downward force to the pump unit.
17 . The pumping system of claim 1 , wherein the collector is a collector configured for being at rest on a seabed.
18 . The pumping system of claim 1 , wherein the liquid is seawater and the objects are selected from the group consisting of fish, krill or other biomass, scallop, rock, pieces of iron ore.
19 . A method of operating the pumping system of claim 1 , comprising: a) determining, estimating or sensing the pressure drop in the first delivery line; and b) arranging the pump unit at a first depth that provides a pump inlet pressure which is sufficient for avoiding cavitation in a pump in the pump unit.
20 . A method of operating the pumping system of claim 1 , comprising: a) determining, estimating or sensing the pressure drop in the first delivery line; and b) operating an adjustable valve to adjust the inlet pressure into a pump in the pump unit to avoid cavitation in the pump.

Description

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS Any and all applications for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are hereby incorporated by reference under 37 CFR 1.57. FIELD The invention concerns the field of fluid transport by means of pumping, and in particular the transport of objects suspended by a liquid. The invention is useful for pumping such suspended objects as pellets, rocks, iron ore, foodstuffs, fish, krill and other aquatic biomass. BACKGROUND Krill are a type of zooplankton that live in the oceans and which are being harvested for commercial purposes. Because of their small size, krill need to be caught with trawls made of fine-meshed plankton nets. Trawling must be performed at low speeds due to high drag forces produced by the fine-meshed nets and in order to avoid clogging and damage to the krill and net. Originally, the krill catch was brought on board the trawler by hoisting the trawl out of the water. This caused the krill to be compressed and thus losing a considerable part of its liquids, which was detrimental to the quality of the catch. Later developments in the technology included pumping the krill from the cod end of the net, through a large hose and onto the trawler. This method increases the capture capacity and the krill processing rate, and improves the quality of the catch as the krill residence time inside the trawl net is reduced. The prior art includes WO 2008/125332 A2, which describes a trawling method and device by means of which the catch is transferred continuously from the trawl net to the trawling vessel during the trawling process. An open fish pump is disposed on the open end of the trawl net, the pump being directed toward the trawl net at the suction side, and the pressure side of which is connected to a delivery hose. The pump is operated by hydraulic oil or other hydraulic fluid supplied under pressure from the surface, or by an electric motor. The caught product guided toward the end of the trawl net during the trawling process is continuously pumped into the delivery hose as a caught product/water mixture during the trawling process, and transported on board the trawling vessel. The prior art also includes FR 1 399 321 (Woborschil), which describes a trawl system having a hose between the trawl cod end and a pumping station, and a pressure duct extending between the pumping station and a surface vessel. The pumping station may be placed in the immediate vicinity of the trawl, preferably directly above, and trawl depth adjustment is accomplished by filling or exhausting the pumping station. The prior art also includes U.S. Pat. No. 3,273,276 (Englesson), which describes a storage and transport device for live fish. The device comprises a trawl connected via a suction line to a floating pump device which is detachably coupled to a floating container. The prior art also includes U.S. Pat. No. 6,343,433 (Granberg), which describes a method and an apparatus for separating target and non-target species harvested from waterbodies. A trawl net and a catch boat are each towable by a trawler by separate towing lines. A catch drawer is mounted within the catch boat for selective vertical movement relative thereto, and a conduit connects the cod end of the trawl net to a forward end of the catch drawer. The conduit permits aquatic organisms to be freely carried through the conduit along with a constant volume of water, which is funneled through the conduit as the trawl net is pulled through the waterbody. A pump maintains the surface level of water in the catch drawer below the surface level of the waterbody in which the catch boat is floating. As the trawl net and catch boat are towed through the waterbody, the constant upwelling of water from the trawl net through conduit delivers a supply of aquatic organisms to the catch drawer. In operation, the flow rate of the pump should match the upwelling water flow rate from conduit. Generally, the pump is only required to return by-catch organisms to the body of water. The prior art also includes WO 2005/004593 A1, which describes a trawl equipped with an elongate, preferably rigid or flexible collecting cage which at an inlet opening is connected to the rear end of the trawl, and from the inlet opening extends into a second portion, defined by walls, roof and bottom which have openings for straining water, and is terminated in a downstream portion. A conveying hose or pipe for conveying biomass from the collecting cage up to a surface vessel opens into the downstream or aft portion of the cage via a funnel. Air or other fluid is supplied from the vessel via a supply hose for injection into the conveying hose or pipe in order, by injector effect, or air lift pump effect (in which the fluid is lifted when the injected air is expanding in the hose, to cause suction of the biomass from the collecting cage to the vessel. The prior