EP1459976A1 - Method and apparatus for recovering polluting fluids - Google Patents

Abstract

In a process to remove marine pollutants from e.g. a shipwreck (1) by pumping, the pump (A1, A2) is presented to an aperture in the hull. Depending upon the viscosity of the pollutant, the pollutant is either first liquefied by heat or energy and then removed by pumping, or pumped out of the hull into another container. The pollutant is transferred to a bladder tank that is then lifted to the surface by inflation of a balloon with gas. On arrival at the surface, the contents of the bladder tank are transferred to another rigid container, pre-filled with water, for treatment and removal. Also claimed is a commensurate assembly.

Description

The invention relates to a method for recovering liquids which are hazardous to the environment according to the preamble of claim 1 and a device for carrying out the method according to the preamble of claim 16.

A possible scenario with regard to the problem to be addressed here is that a tanker loaded with crude oil leaks and sinks to the bottom. Crude oil then escapes from the tanker, which rises to the surface of the water and pollutes the environment. Various methods and devices are known for recovering this crude oil from the water surface, but all of them have disadvantages or can only be used under certain conditions and under certain meteorological conditions. In addition, there are still practically hardly applicable methods and devices by means of which the crude oil can be recovered directly from a sunken tanker. This problem occurs even more when the tanker sinks to the bottom at a deep point.

For example, previous salvage methods provide for fixed installations such as pipes between the leakage point and the pump, which are to be brought down to a sea depth of up to 3500 m. Such fixed installations involve a danger to the environment, especially in high seas. Furthermore, such fixed installations have to be adapted to the respective local conditions at the accident site, which requires a correspondingly long preparation and installation time. For media that are difficult or impossible to pump, and which have to be recovered, previous technologies provide for the thinning of the medium to be recovered using suitable thinners or solvents. The supply of such auxiliary materials requires additional infrastructure and additional installations, which is associated with additional expenditure of time and additional environmental risk. Furthermore, the disposal of such diluted media or the removal of the auxiliary material after the rescue is an additional environmental burden.

The object of the invention is now to propose a method for recovering liquids which are hazardous to the environment or which can be converted into a pumpable state, with which the liquid to be recovered can be recovered quickly, safely, efficiently and under a wide variety of conditions.

This object is achieved by the method steps specified in the characterizing part of claim 1. The basic idea of the invention is to bring a pump device provided for recovering the liquid to the liquid to be recovered or to the hollow body containing the liquid to be recovered and, depending on its viscosity, either to pump it directly or to liquefy it first and then to pump it out and to convey into a container. In this way, the liquid that is hazardous to the environment can be recovered quickly and an immediate danger to the environment can be largely avoided. Once the liquid has been recovered, it can then be disposed of, processed or processed in a suitable location without time pressure.

Preferred methods are described in dependent claims 2 to 15.

In a preferred method, it is proposed to recover the liquid in batches by pumping it out and conveying it into containers that are stable in shape or can be deployed in a balloon-like manner. In this way, an adequate number of such dimensionally stable or balloon-like unfoldable containers can be used to hold the pumped-out liquid, as required, so that even very large volumes of liquid can be recovered, which can be advantageous, for example, if the one to be recovered Liquid is mixed with water or consists mainly of water. There are hardly any limits to the total volume that can be accommodated, particularly when using containers that can be deployed in a balloon-like manner.

Another object of the invention is to propose an arrangement which is advantageously suitable for carrying out the method.

For this purpose, an arrangement is defined in claim 16, which comprises at least one pump device for pumping the liquid to be recovered. The pump device is provided with control and drive means for maneuvering on the water surface or in the water. Such a pumping device can be brought specifically to the liquid to be recovered and the latter can be pumped out.

Preferred embodiments of the arrangement are defined in the dependent claims 17 to 26.

The invention is explained in more detail below with the aid of a schematic drawing. It is assumed in the present example that crude oil is to be recovered from a sunken tanker T.

The arrangement for recovering the crude oil comprises a number of pumping devices A1, A2, A3, A4, A5, A6 and a recovery ship B. In the present case, six pumping devices A1, A2, A3, A4, A5, A6 are shown by way of example, each of which is in a different one Phase in the recovery of the crude oil or in a different application is shown. The respective pump device A1, A2, A3, A4, A5, A6 comprises a pump device 10, 20, 30, 40, 50, 60 provided with a pressure tank 11, 21, 31, 41, 51, 61. In the interior of the respective pressure tank 11 , 21, 31, 41, 51, 61 a pump is arranged, which cannot be seen from this illustration. The one pump device A3 is additionally combined with a device 5 for changing the rheology of the liquid, in particular for liquefying highly viscous to structurally viscous liquids, the structure and mode of operation of which will be explained in more detail below.

The pressure tank 11, 21, 31, 41, 51, 61 of each pump device 10, 20, 30, 40, 50, 60 is designed such that it withstands a pressure of up to 400 bar, corresponding to a water depth of 4000 meters. The respective pressure tank 11, 21, 31, 41, 51 is provided on one side with an inlet flange 12, 22, 32, 42, 52 and on the opposite side with an outlet flange 13, 23, 33, 43, 53. The pump for conveying the liquid is arranged between these two flanges in the interior of the pressure tank 11, 21, 31, 41, 51. In some pumping devices 10, 20, 30, 40, 50, 60, a balloon-like, expandable container 16, 26, 36, 46 is arranged on the outlet flange 13, 23, 33, 43 and is used to hold a large amount of pumped-out liquid, for example up to to 100m ³ . This unfoldable container 16, 26, 36, 46 is made of a synthetic, flexible, oil-tight and oil-resistant fabric, which is provided on the outside with a waterproof coating. Instead of unfoldable containers, dimensionally stable containers can be used, which are flooded with water before the dive.

Furthermore, each pump device 10 is provided with at least one camera 15, with control and drive means 14 for maneuvering in the water, with control instruments and with lighting, the elements mentioned being only partially indicated or not at all. The respective pumping device 10, 20, 30, 40, 50 is connected to the recovery ship B via a control and energy cable 18, 28, 38, 48, 58 and can be navigated remotely similar to a submarine. The pump devices 10, 20, 30, 40, 50 are also provided with means which enable a tight docking and locking on the hollow body from which the liquid is to be recovered or pumped out. Alternatively, funnels or sniffing funnels are provided, which can be attached to the inlet flange 12, 22, 32, 42, 52 of the pumping device 10, 20, 30, 40, 50 and the suction and suction of oil from the water surface to the said surface Serve depths down to 4000 meters. The pump device A6 is provided with such a schematically illustrated sniffer funnel 70. Such a sniffer funnel 70 can also be used in particular if the leak is very large or is not directly accessible. The sniffer funnel can also be used, in particular, to capture liquid or crude oil strands floating or rising in the water. A diameter-adjustable mechanism, for example in the form of an aperture, is preferably provided between the sniffer funnel and the subsequent pump, co-kneader or screw extruder, which mechanism can be adapted to the size of the strand to be pumped out, so that water is sucked in Minimum can be reduced.

As already mentioned, the one pump device A3 is provided with a device 5 for liquefying highly viscous to pseudoplastic liquids, so that they can then be pumped. This device 5 also has a pressure tank 6, which is provided with an inlet flange 7 and an outlet flange 8. The device is preferably also provided with control and drive means 9 for maneuvering in water, with control instruments, with lighting and with means for docking and locking to the respective container. The device 5 is connected to the recovery ship via a control and power cable 68.

A continuously operating melt mixer kneader is arranged in the interior of the pressure tank 6 and is designed, for example, as a screw extruder. Melt mixer kneaders of the type in question here are known in specialist circles in particular also under the term Buss KO-KNETER® and are used, for example, in the chemical and plastics processing industries to heat materials to such an extent by the kneading process and the introduction of mechanical shear energy, that a viscous melt is created that can be pumped using suitable pumps. With kneaders of the generic type, even elastic materials can be heated to such an extent that they can be pumped. A pump device 30 is connected to the outlet flange 8 of the pressure tank 6. Depending on the viscosity of the liquid to be recovered and the other general conditions, the liquid can also be heated by introducing thermal energy, for example by means of a continuous-flow heater. Of course, the introduction of chemical additives to liquefy the highly viscous or pseudoplastic liquid is also conceivable. In contrast to the use of a melt mixer kneader, this variant has the disadvantage that the additive to be introduced into the hollow body itself poses a risk to the environment.

Various scenarios for recovering liquids that are harmful to the environment are explained below.

1. Recovery of crude oil taken up in a sunken tanker T, which has a low viscosity and can be pumped off directly.

The salvage ship B is first driven to the location of the accident or the sunken tanker T. Thereafter, at least one pumping device 10 provided with a deployable container 16 is let into the water. This pumping device 10 is remotely controlled to the sunken tanker T via the energy and data cable. When the tanker T arrives, the pumping device is docked on the tank 1 to be emptied, as is represented by the pumping device 20. It should be mentioned that the pump device 20 was also maneuvered towards the tank 1 by means of its drive means 24. Docking can take place either at a flange 2 provided for this purpose or at another location, in particular at an existing leak or in the Area of the same. It is understood that the pump device 20 is connected to the interior of the tank 1 via a recess or opening after the docking. Since crude oil is lighter than water, the pumping device 20 is advantageously coupled to the upward-facing side of the tank 1 in the region of the highest point at an opening, so that at most water flowing into or flowing into the tank does not pump the crude oil floating on top influenced the sense that water is pumped out instead of crude oil. As soon as the pumping device 20 is docked, the pumping of the liquid tank content can begin. The pumped crude oil is pumped into the deployable container 26. In order to support the pumping process, in particular when the tank 1 is not damaged or has leaked, a further pump device 50 is docked to the tank 1 at another point, preferably at a lower point. This further pumping device 50 is operated in reverse mode in that it is docked with its outlet flange 53 on the tank 1, with the aim of specifically pumping water from the outside into the tank 1 in order to replace the pumped-off crude oil with water so that the tank from prevailing ambient pressure is not pressed in or compressed. Possibly. the tank 1 can also be pressurized or flushed by pumping in water.

After the unfoldable container 26 is filled with the pumped-off crude oil or a mixture of crude oil and water, the pumping device 20 is uncoupled and, together with the filled container 26, guided remotely to the water surface, as is done by the further pumping device 40 with a filled container 46 is indicated. At the surface of the water, the filled container can either be pumped out or hoisted onto the salvage ship B. Another option is to tow the container and tow it to a disposal location. After the pump device 20 has been uncoupled from the tank, a new pump device provided with an empty, unfoldable container is coupled to the opening in the tank 1.

In order to prevent crude oil from escaping after the pump device has been uncoupled, the pump device can be provided with a safety valve (not shown) be connected upstream, which closes the opening with the removal of the pumping device and prevents the crude oil from escaping.

The forced pumping of crude oil out of the tank 1 has the advantage that the leakage of the crude oil through the leak is largely stopped, particularly in the case of a leaked tank 1 in which the leak cannot be sealed, due to the underpressure that arises during pumping inside the tank.

As already mentioned above, instead of deployable containers, dimensionally stable containers can also be used, which are flooded with water before the dive. The crude oil pumped into the dimensionally stable container during the pumping process displaces the water. In order to allow the displaced water to emerge from the dimensionally stable container, this is provided in the lower region with at least one outlet through which the water, which is heavier than crude oil, can escape. Means can be provided in the area of said outlet or outlets to prevent crude oil from escaping.

II. Recovery of highly viscous or structurally viscous, i.e. non-pumpable crude oil.

In this case, the device 5 for liquefying viscous, highly viscous or structurally viscous liquids is used by connecting it upstream of the pump device 30. The pump device 30 can be connected to the device 5 before the dive, so that the pump device 30 and the device 5 dive down to the sunken tanker T and the device 5 with the input flange 7 is docked on the tank 1 to be emptied. Due to the differential pressure between the inside of the device 5 and the interior of the tank 1, the highly viscous crude oil is forcibly supplied to the device 5. The highly viscous crude oil is liquefied in the melt mixer kneader of the device 5, so that it can be pumped into the deployable container 36 via the pump device 30. In this case, too, the emptying of the tank 1 can be promoted by coupling one or more pump device (s) 50 operated in reverse mode to an opening on the tank 1, which leads to the aforementioned differential pressure between the interior of the tank 1 and the device 5, which causes the highly viscous crude oil to be forced into the device 5.

This variant can be used, for example, when the tanker has sunk to the bottom at a deep point and is at a depth of several hundred to a few thousand meters. Since low temperatures of up to approx. 4 ° C prevail at such depths, the crude oil that is liquid and pumpable at over 20 ° C can change its viscosity towards highly viscous, so that it can no longer be pumped. In this case, the device 5 described is used to liquefy viscous, highly viscous or structurally viscous liquids.

III. Pressurizing and / or cleaning a sunken tank

In order to put the tank 1 to be emptied under excess pressure or to clean it, at least one pump device (s) 50 operated in reverse mode is coupled to the tank 1. Instead of a deployable container, a delivery adapter 54 is connected to the inlet flange 52. The pump device 50 operated in the reverse mode conveys ambient water into the tank 1. In this configuration, the tank 1 can also be flushed by the water pumped in by the pump device 50 operated in the reverse mode together with residues in the tank at one point by means of a Pumping device 20 is pumped out.

IV. Recovery of crude oil floating on or floating in the water.

In this case, a sniffing funnel 70 is connected to the inlet flange of the pump device A6, via which the crude oil or a mixture of water and crude oil is sucked in and out. The sucked-in mixture can either be taken up by a deployable container or directly via a flexible line connected to the outlet flange of the pumping device Salvage ship promoted and received there in one or more designated tank (s).

Several pumping devices can be used at the same time for emptying a tank 1. This can be particularly advantageous if the tanker wreck is to be kept in balance or if it is to be emptied as quickly as possible.

In summary, it can be stated that crude oil can be recovered from a medium Newtonian viscosity, which can be pumped directly, to crude oil with a high Newtonian viscosity to crude oil with a high non-Newtonian viscosity, the latter of which cannot be directly pumped by possibly liquefying the crude oil before pumping it out. The method according to the invention manages without auxiliary substances and only requires a supply of electrical energy. The device for carrying out the method according to the invention is mobile, i.e. does not need fixed installations and is therefore quickly ready for use, flexible in adapting to the conditions at the accident site and can be used repeatedly.

It goes without saying that the method and the arrangement according to the invention can also be used to recover liquids other than crude oil. Use of the method or use of the device may even be possible for the recovery of non-liquid, for example powdery, substances if these are water-soluble or can be suspended using water. In this case, one pump device can be used to flood the tank and another to pump the substance.

A great advantage of the method and the arrangement according to the invention can be seen in the fact that it is quickly ready for use and the containers which can be deployed in a balloon-like manner have a very large holding volume. The pumping device and in particular the containers which can be unfolded like a balloon are also so light that they can be transported by means of airplanes or helicopters.

Claims (26)

Method for recovering pumpable liquids or liquids which can be converted into a pumpable state and which float on or in the water or are taken up in hollow bodies which have sunk or leaked in the water, characterized in that a pump device (A1, A2) is brought up to the liquid to be recovered or to an opening of the hollow body (1) containing the liquid to be recovered, and that, depending on its viscosity, the liquid to be recovered is either pumped off directly or liquefied first and then pumped off and into one or more Container is promoted. A method according to claim 1, characterized in that the liquid to be recovered is conveyed into a container via a line connected to the pump device. Method according to Claim 1, characterized in that the liquid to be recovered is conveyed into a container (16, 26) which can be deployed in a balloon-like manner and which can be connected to the pump device (A1, A2). Method according to Claim 1, characterized in that the liquid to be recovered is conveyed into a dimensionally stable container which can be connected to the pump device (A1, A2). A method according to claim 4, characterized in that the dimensionally stable container is flooded with water before the liquid is recovered and is then brought up to the liquid to be recovered. Method according to one of the preceding claims, characterized in that the liquid to be recovered is liquefied before pumping, in particular by introducing thermal energy and / or mechanical shear energy. Method according to one of the preceding claims, characterized in that the pump device (A1, A2) is remotely guided to the liquid to be recovered. Method according to one of claims 1 or 3 to 7, characterized in that the liquid is recovered in batches by pumping it out and conveying it into containers (26, 36, 46) which can be deployed in a stable or balloon-like manner. Method according to one of the preceding claims, for recovering directly pumpable liquids from hollow bodies (1) which have sunk and / or leaked in water, characterized in that at least one pump device (A1, A2) floats up to the respective hollow body (1) and to one Opening is coupled, and that the liquid absorbed in the hollow body (1) is then pumped off and conveyed into a dimensionally stable or balloon-like deployable container (16, 26) and the latter is then guided to the water surface. Method according to one of Claims 1 to 8, for recovering highly viscous or structurally viscous liquids from hollow bodies (1) which have sunk and / or leaked in the water, characterized in that the pump device (A3) floats up to the respective hollow body (1) and to one Opening is coupled so that the liquid absorbed in the hollow body (1) is then conveyed into the pump device (A3) and first liquefied therein and then pumped into a dimensionally stable or balloon-like deployable container (36) and this is then led to the water surface. A method according to claim 9 or 10, characterized in that the hollow body (1) is flooded with the surrounding water during the recovery of the liquid contained therein. Method according to one of claims 9 to 11, characterized in that the hollow body (1) is pressurized by forcibly adding water during the recovery of the liquid contained therein. Method according to one of claims 9 to 12, characterized in that the liquid taken up in the hollow body (1) is pumped out at a point on the hollow body (1) which lies above that point at which water is conducted into the hollow body (1). Method according to one of the preceding claims, characterized in that the container with the salvaged liquid is transported to a location remote from the salvage point, and that the salvaged liquid is then disposed of, further processed or processed. Method according to one of the preceding claims, characterized in that the pumpable liquid is a substance dissolved or suspended in water. Arrangement for carrying out the method according to one or more of the preceding claims, characterized in that the arrangement comprises at least one pump device (A1) for pumping the liquid to be recovered, which with control and drive means (14) for maneuvering on the water surface or in the water is provided. Arrangement according to claim 16, characterized in that the pump device (A1, A2) comprises a pump device (10, 20) provided with a pump. Arrangement according to claim 16 or 17, characterized in that the pump device (A3) has a device (5) for liquefying highly viscous to structurally viscous liquids. Arrangement according to claim 18, characterized in that the device (5) for liquefying highly viscous to structurally viscous liquids comprises an extruder which liquefies the highly viscous to structurally viscous liquid by introducing mechanical shear energy. Arrangement according to one of claims 16 to 19, characterized in that it comprises at least one dimensionally stable or balloon-like unfoldable container (16, 26, 36, 46) which can be fixed to the pump device (A1, A2, A3, A4) and for receiving the salvaged liquid is formed. Arrangement according to claim 20, characterized in that the container (16, 26, 36, 46) is balloon-like, waterproof, oil-resistant and flexible. Arrangement according to one of claims 17 to 21, characterized in that the arrangement comprises a salvage ship (B) and that the respective suction device (10, 20, 30, 40, 50) via a control and energy cable (18, 28, 38 , 48, 58) is connected to the salvage ship (B). Arrangement according to claim 22, characterized in that the salvage ship (B) is provided with at least one tank for holding the salvaged liquids. Arrangement according to claim 23, characterized in that the respective pumping device is connected to the recovery vessel (B) via a delivery line. Arrangement according to claim 24, characterized in that the respective pumping device (60) is provided with a funnel-like suction nozzle (70) for sucking in liquids which float on the water surface or float in the water. Arrangement according to one of claims 17 to 25, characterized in that the respective pumping device (10, 20, 30, 40, 50, 60) is designed to be pressure-resistant in such a way that it withstands pressures of up to 400 bar and at depths of up to 4000 Meters can operate.

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