Oil-water separator for offshore wind farm

Abstract

Disclosed is an oil-water separator for offshore wind farms. The separator is arranged between an oil drain pipe and an accident oil tank, and has a cylindrical structure, and includes an oil storage compartment, a water storage compartment and a partition plate between them. The disclosure can ensure that the accident oil tank is empty under normal operating conditions so that a platform weight is reduced; and an insulation and an electric heating treatments are only performed at the oil-water separator to save insulation project quantity and energy consumption for heating; and a two-stage oil-water separation is achieved in the oil-water separator to avoid mixing oil droplets into water discharged from a water outlet.

Claims

1. An oil-water separator for offshore wind farm, wherein the separator comprises an oil storage compartment, a water storage compartment and a partition plate between the oil storage compartment and the water storage compartment; a top of the partition plate is provided with a vent hole for communicating the oil storage compartment and the water storage compartment, and the vent hole is a round hole; and a bottom of the partition plate is provided with a drainage hole for draining water from the oil storage compartment to the water storage compartment.

2. The oil-water separator of claim 1, wherein an oil inlet pipe is arranged at a top of the oil storage compartment; the oil inlet pipe extends to a bottom of the oil storage compartment, and a distance from an orifice of the oil inlet pipe to a bottom plate is 0.51.0 D; wherein D is a diameter of the oil inlet pipe; multiple oil inlet pipes may be applied as required, and are connected respectively to different main transformer chambers, diesel engine chambers or diesel oil tank chambers.

3. The oil-water separator of claim 1, wherein an oil drain pipe is arranged on a side of the oil storage compartment, and the oil drain pipe is connected to an accident oil storage tank.

4. The oil-water separator of claim 1, wherein a water drain pipe is arranged on a side of the water storage compartment, and the water drain pipe extends to a bottom of the water storage compartment, and a distance from an orifice of the water drain pipe to a bottom plate is 0.51.0 D, wherein D is a diameter of the water drain pipe.

5. The oil-water separator of claim 2, wherein the bottom of the partition plate is provided with the drainage hole at a position away from the oil inlet pipe, and the drainage hole is generally a rectangular hole, and a cross-sectional area of the drainage hole is not less than a cross-sectional area of the drain pipe.

6. The oil-water separator of claim 1, wherein an oil drain pipe is arranged on a side of the oil storage compartment, and a water drain pipe is arranged on a side of the water storage compartment; a height of the oil drain pipe is H1, a height of the water drain pipe is H2 and a height of the drainage hole is H3; wherein H1, H2 and H3 meet the following two requirements: {circle around (1)}H1H2>0.1 m {circle around (2)}H2>(H1H2)/(1Sg)+H3; wherein Sg is a specific gravity of oil, and the specific gravity of transformer oil is 0.9.

7. The oil-water separator of claim 4, wherein a first vent pipe is provided in the oil storage compartment or the water storage compartment, and a second vent pipe is provided in the water drain pipe; and each of the first vent pipe and the second vent pipe is an elbow having a curvature of 180 degree.

8. The oil-water separator of claim 1, wherein liquid level observation tubes are arranged outside the oil storage compartment and the water storage compartment, and each of the liquid level observation tubes is a glass tube whose two ends are connected with a cylinder.

9. The oil-water separator of claim 4, wherein under normal operating conditions, water is stored both in the oil storage compartment and the water storage compartment of the oil-water separator, and a height of water level is the same with a height of the water drain pipe.

10. The oil-water separator of claim 6, wherein in an area where a minimum temperature in winter is lower than 0 C. and water in the oil-water separator may freeze, an outer wall of the oil-water separator is provided with an insulation layer, and if in a colder area, an electric heating equipment is provided.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic view showing an installation position of the oil-water separator in an embodiment.

(2) FIG. 2 is a cross-sectional view of the oil-water separator in an embodiment.

(3) FIG. 3 is a plan view of the oil-water separator in an embodiment.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

(4) Referring to FIG. 1, an oil-water separator for offshore wind farms is described in this embodiment. The oil-water separator is installed between a main transformer accident oil collection pit 1 and an accident oil storage tank 3. Function of the oil-water separator is to separate oil-water mixture discharged from the main transformer accident oil collection pit 1, and collect oil into the accident oil storage tank 3 and discharge water.

(5) Referring to FIGS. 2 to 3, the oil-water separator 2 in this embodiment has a cylindrical structure and includes an oil storage compartment 21, a water storage compartment 22, and a partition plate 23 between the two compartments. A cylinder wall, a bottom plate, a top plate and the partition plate of the oil-water separator are all welded by steel plates with thickness of 8 mm. The total height and the diameter of the oil-water separator are 3 m and 1.5 m, respectively. The partition plate 23 is positioned at a center line of the cylinder, and the oil storage compartment 21 is the same with the water storage compartment 22 in size.

(6) An oil inlet pipe 24 is arranged at top of the oil storage compartment 21, and the oil inlet pipe 24 extends to a bottom of the oil storage compartment 21. In this embodiment, a diameter of the oil inlet pipe 24 is 200 mm, and a distance from an orifice of the oil inlet pipe to a bottom plate of the oil storage compartment 21 is 100 mm. Three oil inlet pipes are adopted in this embodiment, and one of which is connected to a main transformer chamber, and the other one of which with a smaller diameter is connected to a diesel engine chamber.

(7) An oil drain pipe 25 is arranged on a side of the oil storage compartment 21, and the oil drain pipe 25 is connected to the accident oil storage tank 3. A diameter of the oil drain pipe 25 is 200 mm in this embodiment.

(8) A water drain pipe 26 is arranged on a side of the water storage compartment 22, and the water drain pipe 26 extends to a bottom of the water storage compartment 22. In the present embodiment, a diameter of the water drain pipe 26 is 200 mm, and a distance from an orifice of the water drain pipe 26 to a bottom plate of the water storage compartment 22 is 100 mm.

(9) The partitioning plate 23 is arranged between the oil storage compartment 21 and the water storage compartment 22, and a drainage hole 27 is arranged at the bottom of the partition plate 23 at a position away from the oil inlet pipe 24. The drainage hole 27 is a rectangular hole and has a width and a height of 300 mm and 120 mm, respectively.

(10) In this embodiment, the oil drain pipe 25 is provided with a setting height H1=2.6 m; the water drain pipe 26 is provided with a setting height H2=2.4 m; and the drainage hole 27 is provided with a height H3=0.12 m. A specific gravity of transformer oil in this embodiment is 0.9, which meets a condition of H2>(H1H2)/(1Sg)+H3.

(11) Top of the partition plate 23 is provided with a vent hole 28 of the oil storage compartment 21 and the water storage compartment 22, and the vent hole is a round hole with a diameter of 50 mm. Vent pipes 29 and 30 are respectively arranged at tops of the oil storage compartment 21 and the water drain pipe 26. The vent pipe is an elbow having a curvature of 180 degree.

(12) Liquid level observation tubes 31 are arranged outside the oil storage compartment 21 and the water storage compartment 22. The liquid level observation tube 31 is a glass tube, of which two ends are connected with a cylinder body.

(13) Under normal operating conditions, water is stored both in the oil storage compartment 21 and the water storage compartment 22 of the oil-water separator, and a water level and the water drain pipe 26 share the same height of 2.4 m.

(14) The operation process of the oil-water separator according to the embodiment is described as follows.

(15) {circle around (1)} When a fire happens to a certain oil-containing equipment (such as the main transformer) and in order to prevent the fire from expanding, oil (such as an insulating oil of the main transformer) is discharged. Since fire-fighting water has also been ejected at this time, the main transformer oil pit 1 is filled with a mixture of oil and water, which is discharged into the oil-water separator 2 through a pipe.

(16) {circle around (2)} When a large amount of oil-water mixture is injected into the oil storage compartment 21 from the oil inlet pipe 24, an oil always floats on the upper portion of the oil storage compartment 21 due to a less density of oil than that of water, and a water at a bottom is discharged into the water storage compartment 22 through the drainage hole 27 at a bottom of the partition plate 23. With a continuous injection of an oil-water mixture, the oil is discharged from the oil drain pipe 25 at the upper portion of the oil storage compartment 22, and water is discharged into the water storage compartment 22 from the drainage hole 27 and then discharged through the drain pipe 26, thus forms a first oil-water separation.

(17) {circle around (3)} In the water entering the water storage compartment 22, a small amount of oil droplets may be mixed, and oil always floats on top of the water storage compartment 22 according to a density difference of oil and water. Since an orifice of the drain pipe 26 extends to a bottom of the water storage compartment 22, water is always discharged through the water drain pipe 26, and a small amount of oil droplets mixed in is left at the top of the water storage compartment 22, thus forms a second oil-water separation.

(18) {circle around (4)} Oil is discharged from the oil drain pipe 25 and stored in the accident oil storage tank 3. Water is discharged from the water drain pipe 26.