APPARATUS AND METHOD FOR SEPARATION OF WATER FROM AN EMULSION OR MIXTURE OF WATER AND OIL.

The present invention refers to an oil recover unit having a container for the retrieving of a mixture/emulsion of water and oil for the separation of the water from the oil.

On the market existing constructions of this type consist of oil recover units, which are used for the clearing of oil and the separation of water from the oil for e.g. in oil spills in watercourses near beaches, from the surface of water, inside tankers and other places. The oil recover units of today are large, expensive, with complicated structure, ungainly to manage, it therefore takes time to get these in place to get the work done immediately. Large oil recover units do not reach to work over all places, since the environment does not allow for their use or because they take too much space and are too heavy. This is the reason why much of the cleaning up work to separate the oil is done by hand with pitchforks, spades, rakes etc. Previous methods retrieve the oil/water mixture in a container, whereupon one must wait 10 — 20 hours for the oil to rise to the surface so that the oil then can be removed. This takes time and requires large space and has no continuity in the process. Document US 4855065 shows a very large, expensive and complicated structure for the separation of oil from water with mobile parts. Through many stages and by centrifugalizing the water/oil mixture the water can be separated. Document US 2917178 shows another large, ungainly and expensive machine using a complicated process, where the water/oil mixture pours through different rooms and sections in stages, transported from above downwards, the oil being separated from the water and finally filtered through a filter. In document US 1984003 the separation of water from oil takes also place in different stages through to a number of different rooms and sections. This installation shows mainly the same disadvantages as those in the other two documents show. Furthermore the above installations also require high maintenance, which is costly.

The object of the present invention is to solve the problems mentioned above by creating an inexpensive, easily manageable, requiring no maintenance and a well working oil recover unit with few parts and without filter, which functions with a continuous process to soak up and separate water from oil without chemicals in a mixture/emulsion of mainly water and oil from e.g. an oil spill in a watercourse. The characterizing featifes of the invention are mentioned in the following claims.

Thanks to the invention an oil recover unit has been provided, which is small, light, user friendly, inexpensive and effective with few parts and no filter which has to be changed, said recover unit can readily be employed in small places, even in environmentally sensitive areas and with immediate effect continuity, without delay, which is capable of starting cleaning up oil without chemicals from water, before environmental damage occur. The oil recover unit can be used at all kinds of oil spills and because of its small size and low weight it is most suitable for smaller oil spills and in acute situations and can easily be transported by one person.

The invention is described in more detail below with the help of a preferred embodiment example referring to the drawings enclosed, in which

Fig 1 shows a schematic view in a vertical section through an oil recover unit according to the invention and

Fig. 2 shows a perspective view an oil recover unit according to the invention.

The figures show an oil recover unit 1 having a container 5 for retrieval of a mixture/emulsion 2 of water 3 and oil 4, where the separation of water from oil takes place. The retrieval is arranged via an inflow 6 located at the lower part 24 of the container 5. The mixture/emulsion 2 soaks up into a hose 29 connected to the inflow 6, so that the mixture/emulsion 2 then can be pushed up under pressure into the container 5 by help of a pump 8. The oil 4, which has a lower density than water 3, rises upwards in the form of oil particles 16 in the surrounding water and creates an oil bed 17 on the water surface 3, which is continuously lifted up by the water. In one place where the oil particles 16 move upwards, somewhere under the bed of oil, a collecting place 9 is arranged in form of a number of holes 10 in the upper part of a discharging canal 11 or on a flexible upwards directed drainage pipe 25, through which the surrounding water 3 in the mixture/emulsion 2 is conducted away from the container 5, as tapped out water 13 through the discharging canal 11 and out through a lower discharge 14 in the lower part 24 of the container 5. The oil bed 17 is discharged at the upper part 12 of the container 5 via an existing upper discharge 15 and where it is taken care of. The pump 8 is according to the invention connected to

the inflow 6. There is a "bypass"-conduit 18 provided passing the pump 8, which can be connected in order to in a varying degree open and close the same on demand by a first valve 19 to feed the mixture/emulsion 2 totally or partly back again to the pump 8, to a place upstream the pump 8. Hereby a pressure relief is obtained, which slows down the inflow, so that the turbulence in the mixture/emulsion is reduced. However, the turbulence in this part is so large in the mixture/emulsion 2, that the collecting place 9 shall be arranged above this area, where the oil particles have been so large and the turbulence so small, that they move upwards so that the water effectively can run out. The inflow 6, the lower discharge 14, the upper drainage or discharge 15 each is provided with a valve 20, 21 and 22 respectively, which can be opened and closed in a varying degree on demand. The locations of the collecting places 9 can according to the invention be arranged at the lowest level 23 in the container 5, which is located, where the oil particles start moving upwards, and at the highest place at an upper level 31 at a distance 7 from each other, right under the oil bed 17, where the oil particles have not yet been assimilated with the same. Within the distance 7 between the lower and upper level, a removal upwards and downwards may take place by the influence of power at the discharge canal 11 or on the flexible, upwards directed drainage pipe 25, which is connected to the drainage canal 11, preferably in the middle viewed from above the container 5. The holes 10 are now arranged on the sides of the drainage pipes 25 or the upper part of the discharge canal 11, whereby a desired level can be achieved by an adjustment according to the position of the holes 10 in height, so that an optimal separation of the water from the oil can take place at every point of time adapted after what type, quality and viscosity the oil has and what density, depending on the percentage of salt, the water has.

According to a preferred embodiment example of the invention the container is made of stainless steeL, which shows no pores, in order to avoid that the oil particles getting stuck on the inner surfaces of the container. The container 5 has a bottom 26 with an upwards directed cylindrical wall 27 and a roof 28, which hermetically encloses the retrieved mixture/emulsion 2. The height of the container 5 is at least twice as long as its width. The roof 28 has a leaning part towards the horizontal plane, whereby the oil bed 17 touches the roof 28, when it reaches the upper discharge 22, whereby possible particles of water and particles of air in the oil bed will be pressed out of the same and flatten it, whereby the oil more easily can be discharged. The highest point of the roof

28 is now directed in the same direction, as the upper discharge 22, which is arranged in the wall mainly at the same height as the lowest point of the roof. The oil recover unit 1 can be produced small and light, so that it can be transported quickly and easily and also on a small two wheeled carriage with a handle, and the container will in this way have space for less than 100 litres with an attached hose 29 having a length of approximately 25 meters, which is connected to the inflow 6. The hose 29 has a non return valve 30 in order to avoid a flow back again out of the tube of the retrieved mixture/emulsion. To make the mixture/emulsion 2 more liquid flowing, it can be heated on a place under the oil bed, preferably at the inflow 6 with a surrounding heated surface before it reaches the pump 8 and fills the container 5.

According to the invention the retrieval of the mixture/emulsion and the separation of the water from the oil with the oil recover unit 1 takes place, according to a process, in different stages. In a first step (1) a second valve 20 is opened at the inflow 6 and a fourth valve 23 at the upper discharge 15, at the same time as the first and a third valve 21 at the lower discharge 14 are closed. The pump 8 is started, whereby the hose 29 soaks up parts of the mixture/emulsion 2, which later under pressure is pushed up until the container 5 is filled up to the upper discharge 15. Then, in a second step (2), the pump 8 is shut off during a preferred space of time until a preferred thickness of the oil bed 17 has been created. In a third step (3), the discharged water starts to fill the discharge canal 11, whereby the third valve 21 is opened for discharging the discharged water via the lower discharged 14 at the same time as the pump starts again to keep the oil bed continuously in level with the upper discharge 15, where the oil is discharged, so that the oil bed 17 is continuously filled with new oil particles. After this, in a fourth step (4), the first valve is opened 19 on demand to such a degree, that an adequate decrease of turbulence is achieved. In a fifth step (5), if the percentage of oil is higher than the desired percentage of oil in the discharged water, this is fed in return to the inflow 6, whereby during the third to fifth steps (3-5) all valves are adjusted at will, so that the oil recover unit 1 continuously and optimally can soak up the mixture/emulsion and optimally be able to separate the water from oil. The process of the retrieval of the mixture/emulsion 2 and separation of water from oil is according to the invention continuously manoeuvred by a computer/processor, that via sensors, which are arranged somewhere in the oil recover unit and which at any moment sense and manoeuvre different functions in the process

after desired, predetermined programmed targets in the computer/processor, such as e.g. when, how much and for how long time the valves shall be open or closed and the level of height of the collecting place 9 and the activities of the pump and the heating.