Separating apparatus

Abstract

The invention relates to a separating apparatus (10) for separating oil, fat or other residues from wastewater, having - a separating vessel (11), - a feed device (12), in particular a feed pipe (13), which is adapted for a maximum wastewater feed flow Q into the separating vessel (11), - a drain pipe (14) for cleaned wastewater, having a first inlet opening (15) and a first outlet opening (16), and - a collecting pipe (17) for the separated oil and / or fat, having a second inlet opening (18) and a second outlet opening (19), wherein the first outlet opening (16) forms a first, in particular horizontal, overflow edge (20), over which cleaned wastewater flows during use, and the second outlet opening (19) forms a second, in particular horizontal, overflow edge (21), over which the separated oil and / or fat flow(s) during use, wherein - the second overflow edge (21) is arranged higher up than the first overflow edge (20), - a vertical distance d is formed between the two overflow edges (20, 21), and - during use, an overflow height d0 of the cleaned wastewater is formed at the first overflow edge (20) in the vertical direction with a maximum wastewater feed flow Q, where: d ≥ substantially 1.1 * d0.

Description

[0001] Separation device

[0002] Description

[0003] The invention relates to a separation device having the features of the preamble of claim 1. Such a separation device is known, for example, from CN 106946370 A.

[0004] Separation systems are traditionally used to treat wastewater in buildings. For example, commercial kitchens, gas stations, and other businesses may be equipped with separation systems to separate coarse and fine solids, as well as grease and oil, from wastewater before it enters the sewer system.

[0005] To enable comprehensive pre-treatment, such separation devices can comprise several different units for the step-by-step purification of the wastewater. For example, the separation device from the aforementioned CN 106946370 A comprises an inlet device for supplying the wastewater, a separation tank for separating grease, oil, and sludge, a drain pipe for discharging the treated wastewater, and a collection pipe for the separated grease and oil.

[0006] Furthermore, the separator tank for separating oil and grease according to CN 106946370 A features an oil / grease drain pipe for removing the separated oils / greases. To remove air from the separator tank, a vent pipe is located in the upper part of the separator tank. The separation device has many components and is complex in design.

[0007] The invention is based on the object of improving the separation device known from the prior art mentioned at the outset in such a way that reliable grease / oil and water separation is achieved with a simplified structure.

[0008] According to the invention, this object is achieved by a separation device having the features of claim 1.

[0009] Specifically, the problem is solved by a separation device for separating oil, grease, or other residues from wastewater, comprising a separation tank and an inlet device, in particular an inlet pipe. The inlet device is adapted for a maximum wastewater inlet flow Q into the separation tank. The separation device has an outlet pipe for purified wastewater with a first inlet opening and a first outlet opening, and a collecting pipe for the separated oil and / or grease with a second inlet opening and a second outlet opening. The first outlet opening forms a first, in particular horizontal, overflow edge, over which purified wastewater flows during use. The second outlet opening forms a second, in particular horizontal, overflow edge, over which the separated oil and / or grease flow during use. The second overflow edge is arranged higher than the first overflow edge.A vertical distance d is formed between the two overflow edges. During use, an overflow height do of the treated wastewater forms at the first overflow edge in the vertical direction at maximum wastewater inlet flow Q.

[0010] Where: d > essentially 1.1 * do

[0011] The principle of the communicating tube is used to retain fats and / or oils by separating the water surfaces. When the drain pipe and the collecting pipe are completely filled with wastewater, the heights of the equilibrium liquid columns are inversely proportional to the specific gravity. The second overflow edge of the collecting pipe is positioned higher than the first overflow edge of the drain pipe. Due to height differences between the two overflow edges, different liquid heights form in the drain pipe and the collecting pipe. In this context, it should be noted that the vertical distance d between the two overflow edges is dimensioned such that d is at least 10% greater than the overflow height do. This is the overflow height do that occurs at maximum wastewater inlet flow Q. The maximum wastewater inlet flow Q is a fixed parameter of the separation device.

[0012] It has been shown that such an arrangement of the two overflow edges offers greater reliability in the separation of grease and / or oil and contributes to secure separation. The arrangement of the overflow edges described here contributes significantly to keeping the interface between water and grease and / or oil below the second overflow edge.

[0013] In order to ensure reliable grease / oil and water separation at maximum inlet flow Q during use, the lower limit of d can be determined using the overflow height do, for example in an experimental series of tests. The lower limit of d indicates how large d should or must be at least so that the wastewater does not penetrate to the second overflow edge and enter the grease container. To prevent the wastewater from penetrating to the second overflow edge, d is chosen so that d > 1.1 * do applies. In this case, d can be in particular d > 1.3 * do, in particular d > 1.5 * do, in particular d > 2.0 * do, in particular d > 2.5 * do, in particular d > 3.0 * do, in particular d > 3.5 * do, in particular d > 4.0 * do, in particular d > 4.5 and in particular d > 5.0 * do.

[0014] To measure the overflow height (do) that occurs during use, a dipstick can be used. The dipstick is positioned vertically at the first overflow edge and the resulting overflow height (do) is read from the water mark on the dipstick.

[0015] At maximum flow velocity, the maximum wastewater inlet flow Q occurs in the separator tank.

[0016] As an alternative to the simple measurement method, the overflow height do can be calculated as described in the Francis equation.

[0017] To determine the maximum inflow flow Q as a function of the overflow height do, the Francis equation known from hydraulic engineering is used:

[0018] The Francis equation, in its form, can be derived from the relationship for maximum discharge. The overflow coefficient |i is a dimensionless coefficient used in hydraulic engineering to calculate the amount of water overflowing the overflow edge and depends on the shape of the overflow and the influence of the wastewater inflow velocity. A guideline value for rectangular overflow edges is |i ~ 0.6. For other overflow edge shapes, the overflow coefficients vary to a greater or lesser extent.

[0019] The gravitational force (acceleration of gravity) g has the value g = 9.81 on the earth's surface.

[0020] B is referred to as the overflow width. The width B of the overflow is determined at the first overflow edge depending on the wastewater inlet flow Q.

[0021] The separation device according to the invention has a simple structure comprising a separation tank, an inlet device for supplying the wastewater to be treated, a drain pipe for discharging the treated wastewater, and a collection pipe for the separated oil and / or grease. This simple structure does not preclude the use of additional elements.

[0022] The residues in the wastewater settle in the lower part of the separator tank by gravity. Oil and grease are insoluble in water. Because they have a lower specific gravity than water, they float to the surface. The mixture of oil and / or grease and water thus separates into an oily and a watery phase. Droplets of oil and / or grease flow together and rise into the collection pipe. The treated wastewater is discharged via the drainpipe and, for example, ends up in the sewer system.

[0023] Preferred embodiments of the invention are specified in the subclaims.

[0024] Preferably, the drain pipe and the collecting pipe are arranged vertically, at least in the area of ​​the respective overflow edge. This allows the separated grease and / or oil to float into the collecting pipe according to the principle of different densities as the wastewater level in the separator tank rises. By utilizing this simple physical principle, it is possible for both the separated grease and / or oil and the purified water to be drained over the respective overflow edges through a simple design of the drain pipe and the collecting pipe.

[0025] Furthermore, the volume of the collecting pipe is adjusted to completely retain the separated grease and / or oil at maximum fill level. This allows the grease and / or oil to be stored in the collecting pipe and then drained away. This has the advantage of allowing the collected grease and / or oil to be thoroughly drained away.

[0026] In a further preferred embodiment, the separator tank is designed as a single-chamber tank into which the inlet device, the outlet pipe, and the collecting pipe each open. The advantage of this embodiment is that it ensures a particularly simple and functionally reliable separation of grease and / or oil and water.

[0027] In a preferred embodiment, the separation vessel can be designed as a dual-chamber tank with a first chamber and a second chamber, wherein the inlet device opens into the first chamber and the outlet pipe and the collecting pipe each open into the second chamber. The first and second chambers are connected by at least one coalescing element, in particular a coalescing pipe, in which fat and / or oil droplets dispersed in the water coalesce to form larger fat and / or oil droplets with greater buoyancy. In this way, the separation of the oil-water mixture takes place through the principle of gravity with physical processes of adsorption and coalescence. This ensures that fat and / or oil droplets present in the water coalesce to form larger fat and / or oil droplets with greater buoyancy and rise upwards into the collecting pipe. This significantly improves the separation of fat and / or oil from the wastewater.

[0028] Furthermore, the two chambers can be separated by a cover plate that extends diagonally downwards from the second inlet opening of the collecting pipe. With the help of the diagonally downwards cover plate, grease and / or oil, as well as coarse residues, can be moved in a targeted manner toward the first or second chamber.

[0029] In a further preferred embodiment, the separator tank can have an air device. During use, a layer of grease can form on the cover plate or in the collecting tube, reducing the cross-section of the collecting tube. The air device enables mechanical cleaning of the cover plate and the collecting tube. In this mechanical cleaning method, air bubbles of varying sizes act as an air brush and loosen the deposits. The air flows through the collecting tube and out of the separator. The air cleaning is extremely gentle on the cover plate and the collecting tube, unlike other cleaning methods. Cleaning is more environmentally friendly and safer without the use of chemicals. Another advantage is that the air cleaning can be used very flexibly.

[0030] Preferably, the collecting pipe has at least one heating foil surrounding the outer wall of the collecting pipe to liquefy the separated fat and oil. This particularly simple design prevents animal fats and oils from solidifying at low temperatures.

[0031] Further preferably, the heating foil can be detachably connected to the outer wall of the collecting pipe. This has the advantage that the solidified grease and / or oil can be liquefied by simply attaching the heating foil to the outer wall of the collecting pipe, such as pressing, gluing, or clamping. It is conceivable to completely cover the collecting pipe with heating foil to prevent heat loss to the environment.

[0032] Furthermore, the collecting pipe can have a floating ball positioned between the oil / grease layer and the water layer during use. The density of the floating ball lies between the density of the water and the density of the grease and / or oil. When using the air device, it is conceivable that a larger amount of air could force the water layer to reach the second overflow edge and enter the grease container. In this case, the floating ball floats to the top of the collecting pipe and seals it. This makes it possible to temporarily seal the collecting pipe with a simple structural element, preventing unwanted discharge of wastewater into the grease container.

[0033] Conveniently, the distance d between the two overflow edges is at least approximately 25 mm. The vertical distance d of at least approximately 25 mm enables reliable separation of grease and / or oil, as described in the present application. In this way, the wastewater can be prevented from entering the grease container at maximum wastewater inlet flow Q due to a rise in the water level in the separator tank. By utilizing the simple physical principle of the communicating pipe, grease and / or oil can be retained by separating the water surfaces.

[0034] The invention is explained in more detail below with reference to the attached schematic drawings.

[0035] In these show

[0036] Fig. 1 shows the section of a separating device according to a preferred embodiment of the invention;

[0037] Fig. 2 shows the section of a further separation device according to a further embodiment of the invention;

[0038] Fig. 3 shows the section of a further separation device according to a further embodiment of the invention.

[0039] Fig. 1 shows an embodiment of a separation device 10 according to the invention. This involves the application of the separation device for separating oil, grease, or other residues from wastewater in operations that generate greasy wastewater, particularly in kitchens and meat processing plants. Other applications are conceivable, for example, for separating oil, grease, or other residues at gas stations.

[0040] The separation device 10 comprises a separation tank 11. Grease and / or oil and other residues from wastewater are separated in the separation tank 11. The separation tank 11 is designed as a single-chamber tank for separating oil, grease, or other residues from wastewater. The separation tank 11 can be cuboid-shaped, as shown in Fig. 1. Other geometries of the separation tank 11 are conceivable.

[0041] Furthermore, the separator tank 11 has an inlet device 12, in particular with an inlet pipe 13, which is adapted for a maximum wastewater inlet flow Q into the separator tank 11. The separator tank 11 has an outlet pipe 14 for the treated wastewater, with a first inlet opening 15 and a first outlet opening 16. The outlet pipe 14 can be connected to a piping system, for example, a sewer system. In the example according to Fig. 1, the outlet pipe 14 is designed as a cylindrical pressure pipe. Other shapes of the outlet pipe are possible.

[0042] Furthermore, the separator tank 11 has a collecting pipe 17 for the separated grease and / or oil, with a second inlet opening 18 and a second outlet opening 19. According to Fig. 1, the collecting pipe 17 is made of an inflexible material. The collecting pipe 17 can be made of a dimensionally stable material, particularly stainless steel, to ensure good heat transfer. Other materials that do not have a negative effect on water are conceivable.

[0043] The grease and / or oil rises in the wastewater and forms a layer of grease and / or oil in the collecting pipe 17. The first outlet opening 16 forms a first, in particular horizontal, overflow edge 20, over which purified wastewater flows during use. The second outlet opening 19 forms a second, in particular horizontal, overflow edge 21, over which the separated oil and / or grease flows during use, wherein the second overflow edge 21 is arranged higher than the first overflow edge 20. Such an arrangement of the two overflow edges 20 and 21, on the one hand, prevents the water from entering the grease container and, on the other hand, enables reliable separation of grease and / or oil and water in the separator container 11 during use, at maximum wastewater inlet flow Q. The overflow edges 20 and 21 have rectangular edge shapes. Other edge shapes for forming the overflow edges are possible.Furthermore, a vertical distance d is formed between the two overflow edges 20 and 21.

[0044] During use, an overflow height do forms in the vertical direction at the first overflow edge 20 at maximum wastewater inlet flow Q. The vertical distance d and the overflow height do are crucial for the reliable separation of grease and / or oil. It has been shown that when d < do the wastewater penetrates to the second overflow edge 21 and overflows it. This allows the water to enter the grease container. To prevent wastewater from being discharged, the overflow height do is used to determine the lower limit of d according to d > 1.1 * do. In this case, d can be in particular d > 1.3 * do, in particular d > 1.5 * do, in particular d > 2.0 * do, in particular d > 2.5 * do, in particular d > 3.0 * do, in particular d > 3.5 * do, in particular d > 4.0 * do, in particular d > 4.5 and in particular d > 5.0 * do.

[0045] The vertical distance d selected in this way has proven to be particularly efficient in ensuring reliable separation in the separation vessel 11.

[0046] Preferably, the distance d between the two overflow edges 20 and 21 is at least about 25 mm.

[0047] The separation device 10 in Fig. 2 is identical to the separation device 10 in Fig. 1 except for the dual-chamber tank with a first and a second chamber 22 and 23, the cover plate 25, and the coalescence element 24. Reference is therefore made to the above explanations. The features and functions described in this context are also disclosed and claimed in connection with Fig. 2.

[0048] In Fig. 2, the separation device 10 comprises a separation tank 11. The separation tank 11 is designed in Fig. 2 as a dual-chamber tank for separating oil, grease, or other residues from wastewater. The wastewater may contain coarse particles, fine particles such as sludge, as well as floating liquids such as oil and / or grease. In this specific case, the first chamber 22 serves to collect coarse and fine particles such as sludge. The coarse and fine particles contained in the wastewater sink in the separation tank 11 and form a sludge layer. In the second chamber 23, the grease and / or oil rises into the collecting pipe 17 and forms a layer of oil and / or grease in the collecting pipe 17.

[0049] According to Fig. 2, the inlet device 12 opens into the first chamber 22 of the separating tank 11. The outlet pipe 14 and the collecting pipe 17 open into the second chamber 23 of the separating tank 11.

[0050] The first chamber 22 and the second chamber 23 are fluidly connected by at least one coalescing element 24, in particular a coalescing tube. The coalescing element 24 can be designed in various ways. For example, it is conceivable to provide the coalescing element 24 with openings, holes, or the like. Other variants for achieving coalescence, such as metal sheets, are also conceivable.

[0051] The two chambers 22 and 23 are separated by a cover plate 25. The cover plate 25 extends diagonally downwards from the second inlet opening 18 of the collecting tube 17. The cover plate 25 serves to spatially separate the chambers 22 and 23.

[0052] The separation device 10 in Fig. 3 is identical to the separation device 10 in Fig. 2 except for an air device 26, a heating foil 27, and a floating ball. Reference is therefore made to the above explanations. The features and functions described in this context are also disclosed and claimed in connection with Fig. 3.

[0053] In Fig. 3, the separator tank 11 has an air device 26. In this specific case, the air device 26 is used for mechanically cleaning the cover plate 25 and the collecting pipe 17. The air flows out of the separator through the collecting pipe.

[0054] Fig. 3 further shows that the collecting tube 17 has at least one circumferential heating foil 27 and is detachably connected to the outer wall of the collecting tube 17. In Fig. 3, the heating foil 27 is fully connected to the outer wall of the collecting tube 17. It is conceivable that the collecting tube 17 can be provided with the heating foil 27 both fully and partially. Furthermore, during use, the collecting tube 17 has a floating ball 28 arranged between the oil / grease layer and the water layer. Fig. 3 shows the floating ball 28 made of plastic. Other objects with a lower density than water can be used as the floating ball 28.

[0055] List of reference symbols

[0056] 10 Separation device

[0057] 11 Separator tanks

[0058] 12 Inlet device

[0059] 13 Inlet pipe

[0060] 14 Drain pipe

[0061] 15 first entrance opening

[0062] 16 first exit opening

[0063] 17 Collector pipe

[0064] 18 second entrance opening

[0065] 19 second outlet opening

[0066] 20 first overflow edge

[0067] 21 second overflow edge

[0068] 22 first chamber

[0069] 23 Second Chamber

[0070] 24 Coalescence element

[0071] 25 Cover plate

[0072] 26 Air device

[0073] 27 Heating foil

[0074] 28 Floating Ball

Claims

Claims 1. Separation device (10) for separating oil, grease or other residues from waste water with - a separating tank (11), - an inlet device (12), in particular an inlet pipe (13), which is adapted for a maximum wastewater inlet flow Q into the separator tank (11), - a drain pipe (14) for purified waste water with a first inlet opening (15) and a first outlet opening (16) and - a collecting pipe (17) for the separated oil and / or fat with a second inlet opening (18) and a second outlet opening (19), characterized in that the first outlet opening (16) forms a first, in particular horizontal, overflow edge (20) over which purified waste water flows during use, and the second outlet opening (19) forms a second, in particular horizontal, overflow edge (21) over which the separated oil and / or fat flows during use, wherein - the second overflow edge (21) is arranged higher than the first overflow edge (20), - a vertical distance d is formed between the two overflow edges (20, 21) and - in use, an overflow height do of the treated waste water is formed at the first overflow edge (20) in the vertical direction at maximum waste water inlet flow Q, where: d > substantially 1.1 * do.

2. Separation device (10) according to claim 1, characterized in that the vertical distance d is in particular d > 1.3 * do, in particular d > 1.5 * do, in particular d > 2.0 * do, in particular d > 2.5 * do, in particular d > 3.0 * do, in particular d > 3.5 * do, in particular d > 4.0 * do, in particular d > 4.5 and in particular d > 5.0 * do.

3. Separation device (10) according to claim 1, characterized in that the drain pipe (14) and the collecting pipe (17) are arranged vertically at least in the region of the respective overflow edge (20, 21).

4. Separation device (10) according to claim 1 or 3, characterized in that the volume of the collecting pipe (17) is adapted to completely retain the separated fat and / or oil in the collecting pipe (17) at maximum fill level.

5. Separation device (10) according to one of the preceding claims, characterized in that the separation container (11) is designed as a single-chamber tank into which the inlet device (12), the outlet pipe (14) and the collecting pipe (17) each open.

6. Separation device (10) according to one of the preceding claims, characterized in that the separation container (11) is designed as a double-chamber tank with a first chamber (22) and a second chamber (23), wherein the inlet device (12) opens into the first chamber (22) and the outlet pipe (14) and the collecting pipe (17) each open into the second chamber (23), wherein the first and second chambers (22, 23) are fluidly connected by at least one coalescing element (24), in particular a coalescing pipe, in which fat and / or oil droplets distributed in the water flow together to form larger fat and oil droplets with more buoyancy.

7. Separation device (10) for separation according to claim 6, characterized in that the two chambers (22, 23) are separated by a cover plate (25) which extends obliquely downwards from the second inlet opening (18) of the collecting pipe (17).

8. Separation device (10) according to one of the preceding claims, characterized in that the separating container (11) has an air device (26) for cleaning the bevelled cover plate (25) and the collecting pipe (17).

9. Separation device (10) according to one of the preceding claims, characterized in that the collecting pipe (17) has at least one circumferential heating foil (27) lying against the outer wall of the collecting pipe (17) in order to liquefy the separated fat and oil.

10. Separation device (10) according to claim 9, characterized in that the heating foil (27) is detachably connected to the outer wall of the collecting pipe (17).

11. Separation device (10) for separation according to one of the preceding claims, characterized in that the collecting pipe (17) has a floating ball (28) arranged in use between the oil / fat layer and the water layer.

12. Separation device (10) according to claim 11, characterized in that the floating ball (28) is movable in the collecting pipe (17) and, when the water level is high, floats into the upper region of the collecting pipe (17) so that the collecting pipe (17) is temporarily closed.

13. Separation device (10) according to one of the preceding claims, characterized in that the distance d between the two overflow edges (20, 21) is at least about 25 mm.

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