WO1997019229A1

WO1997019229A1 - Swift and cheap method of skimming huge oil spills with any tanker's equipment without chemicals

Info

Publication number: WO1997019229A1
Application number: PCT/GR1995/000023
Authority: WO
Inventors: Ilias Gyftonikolos
Original assignee: Ilias Gyftonikolos
Priority date: 1995-11-22
Filing date: 1995-11-22
Publication date: 1997-05-29
Also published as: EP0807196A1; AU3878995A

Abstract

By this method we use the cargo pumps and the cargo lines at the manifold where we connect the flexible hoses to the EDUCTOR and with it we skim the oil-polluted sea water into the cargo tanks. With the mooring wires we keep the OIL BOOM tight to the side of the ship and with the life-boats we pull the free edges of it in a v-shape to the bow of the ship. With the large capacity of the cargo tanks of the tanker and in the allowed loaded draught ballast condition we have the ability to use a high capacity EDUCTOR in order to achieve by the suction, a surface current and in that way we have better results. The same method of skimming can be used with pumps from the shore in the discharging ports (refineries) for ballasting with surface polluted water up to the arrival ship's loaded condition and then changing of it in the open sea with clean ballast. (Many countries suggest on changing clean ballast in the open sea for oil tankers).

Description

SW 1FT AND CHEAP METHOD OF SKIMMING HUGE OIL SPILLS WITH ANY TANKER'S EQUIPME NT WITHOUT CHEMICALS

The method refers to the skimming or the oil of the sea surface in the event of a huge oil spill, with a use of medium or large size tankers m ballast condition and with cargo tanks filled with sea water to the maximum allowed draught.

It uses the high output of cargo pumps and with the use of the tanker's cargo lines we are able to achieve at the manifold (port and starboard) pressure of 8 - 9 kg/cm2 with which the EDUCTOR operates at a maximum rate of 800 m3/h.

The skimmed oil and water from the sea surface we discharge with flexible hoses form the top of the cargo tanks through the butterworth holes or in case of a new tanker (built after 1989) through the VAPOR line which is connected with all cargo tanks at the top. fig 2.

The above loaded quantity we balance by discharging of equal quantity from the cargo lines which are located m the bottom of the cargo tanks with the method of : BY GRAVITY, fig 3. For the enclosement of the oil spill we use berthing wires under the ship's keel where we make last the OIL BOOM with sackles tightened at a distance from the sea surface equal to the width of the oil boo in order to avoid oil leakage towards the stern of the ship.

The oil boom can be 200 meters long or over and is tightened to the port and the starboard of the ship the same wav as the cargo pipe lines arrangement at the manifold is the same, fig 1.

Bv using the two life boats of the tanker we form a v-shape towards the bow of the ship with the oil boom in order the suction to cause a surface current to the suction well, fig 1 & 4. The suction well is an oil drum cut in two and reinforced with an iron ring - fig 4 - which we submerge in a wav that the top to be 1 - 2 cm below the sea surface, in the narrowest point of the v-shaped oil boom at the side of the ship and we adjust the incoming quantity to be the same with the suction one of the EDUCTOR. There are methods of oil spills cleaning with small size ships

(THE SKIMMERS) which are stationed in oil ports and refineries but as thev are of small capacity, it is impossible to use them for huge oil spills. In addition, these skimmers use chemical which destroy sea life. This method exploits the characteristics of the EDUCTOR which operates with the sea water pressure (8-9 kg/cm2) with the large output ol the ship's cargo pumps and the continuous use of them, This method can be used in bays, rivers with small ships or in open seas where the weather conditions allow it. In addition we can clean any polluted area with strong pumps from the shore where there is refinery with the combination of de-contamination bv radiation, a wav that is practised at the refineries when they receive dirtv ballast from the oil tankers.

It is possible to use the method on the stranded ships by skimming the oil with another tanker.

Finally it is possible by the same method to skim the polluted water of the surface at the oil discharge ports as ballast to the cargo tanks in order in the open sea to change ballast into the clean cargo tanks as it is required by many countries.

In this way we can improve the quality of the water in the oil ports as the pollution is bigger on the surface.

There are always passing tankers in areas where oil ports are located and it is cheap hiring of VLCCs due to the over capacity, but the medium size tankers (80.000 - 100.000 tons) are more in number.

In shallow waters we use smaller size tankers or longer oil boom with bigger tankers.

In the beginning of the operation we use the ship's life boats but later we can replace them with small motor boats, fig. 1.1.

The tanker can be anchored if it is possible or we use the engine to keep the bow of the ship towards the oil spill.

The required gear can be stored in all oil ports or oil platforms in order to be ready to be carried in short time i.e. helicopter. We can achieve from the starboard and port side of the ship a rate of 1.600 m3/h or more bv SUBMERSIBLE PUMPS using the suction well, fig 4.

The ship must have enough ballast water equal to the allowed draught in order to have the minimum freeboard and have better suction, fig 3.1. The advantage of the method is that the decanting of the oil can occure continuously during the operation, fig 3.

With the use of the submersible parts we increase the rare and with this the surface current of the oil spill towards the suction wells and we reduce the time of the skimming of the oil spill.

At the end ol the operation we discharge the oil contaminated water to the nearest refinery and in case we need more tank capacity we use another tanker.

The fig. 1 shows the view from above with the lifeboats fig. 1 port and starboard holding the oil booms in V shape in order the caused surface current from the suction wells. The fig 2 shows the wav of rigging of the flexible hoses (no 5,7,10) to the Eductor. In order to secure the OIL BOOM no.8 we use the mooring wire no.l which we secure at the aft of the ships MANIFOLD with a shatch block no.2.

With a small diameter wire we pass the mooring wire no.l under the keel and we connect it with the mooring wire of the port side. With the above small wire no.3 we secure two shackles for fastening the OIL BOOM no.8 at a distance equal to the width of it, which we lower in order the higher one to touch the sea surface and the other we submerge, and make fast the small wire on deck.

We heave tight the mooring wires to the side of the ship and secure the OIL BOOM no.8 to the shackles no.4 using the life boat.

The connection of the flexible hose no. is done in such a way in order the direction of the EDUCTOR to be towards the discharging no.l^" BUTTERWORTH HOLES of VAPOR LINE which is connected with all the cargo tanks form the top. The fle ible hose no.⁷ we secure m the suction well no.12 which we submerge in such wav that the top to be 1-2 cm below the sea surface. The holding wire of the suction well no.18 we secure on deck in order to adjust the position of the suction well no.12. Also the same we arrange for the securing wires. With the cargo pumps no.16 which are interconnected with the cargo lines, we reach a sea water pressure of 8-9 kgs/cm2 in order to operate the EDUCTOR and to cause the surface current no 14 tor the better skimming of the oil spill.

The fig. 3 shows the various stages of the filling cargo tanks. The stage no.l white is the initial stage of the cargo tank filled with sea water.

The stase no.2 dark is the final stace of the careo tank after the discharge by gravity of the clean sea water during the skimming operation.

The fig. no.4 shows the suction well no.] with the suspension - stabilization wires no.4 and the direction of the tightened up position on deck no.3-5, the reinforced ring no.2 with the securing points of the wires.

The fιg.no5 shows the flexible hose no.l and iron frame no.2 which is used to avoid the phenomenon oi «cuρpmg» during the operation.

Claims

1. Method of skimming of huge oil spills with VLCCs or other size tankers in ballast condition.

2. Method of the demand no.1 by using the cargo pumps to achieve sea water pressure at the manifold through the ship's cargo lines 8-9 kg/cm2 with which the EDUCTORS operate.

3. Method of the demand no.1 by securing the EDUCTORS to the ship's cargo lines at the MANIFOLD with flexible hoses (using the usual type of connection ASA) in such a way in order the suction side of the EDUCTORS to be directly on top of the suction wells.

4. Method of the demand no.1 by using the mooring wires which we pass under the keel and have them heaved tightly in order to secure the OIL BOOM on the already secured shackles of the mooring wires in such a way so as to avoid leakage from the OIL BOOM to the stern of the ship.

5. Method of demand no.1 by using the suction well which is made from half oil drum, reinforced on the top by an iron ring where we connect the suspension and stabilization wires. This oil drum is the only way to skim efficiently the oil surface polluted water. This can also be replaced by any other similar construction.

6. Method of demand no.1 by using pumps from shore with the above suction wells and load the tanker with the polluted sea water in the discharging port, equal to the quantity of the discharged cargo. By this way we can change the polluted water at the open sea and load clean ballast m the SEGREGATED BALLAST TANKS.