Device for separating oil and water and method therefor

Abstract

Device (1) for separating oil and water, comprising: a housing (10) comprising: an inlet (11) for introducing an oil-water mixture into the housing (10), an oil outlet (12) for discharging separated or separated oil from the housing (10), and a water outlet (13) to drain water from the housing (10), wherein the inlet (11) is provided in a lower region of the housing (10), so that the oil-water mixture can be introduced from the lower region into the housing (10) and can flow upwards along a flow path (30) with a flow direction (S) which is opposite to the force of gravity, and the housing (10) has a flow brake (20) in the flow path (30), which is to be passed by the oil-water mixture during the upward flow and thereby brakes the upward flow, characterized in that the water outlet is arranged in the lower part of the housing (10), and in the lower region of the housing, a limiting plate is provided which divides an interior of the housing into two regions at least in the lower region of the housing, and is aligned with a longitudinal extent of the limiting plate (40) vertically in the housing (10), wherein the inlet opens into a first area of the two areas and the water outlet is arranged in the second area.

Description

Technical field

[0001] The present disclosure relates to a device for separating oil and water, in particular for separating or separating oil bound in expanded and condensed steam of a steam engine, a method for separating oil and water. background

[0002] Decentralized combined heat and power (CHP) plants have long been established as a beneficial alternative to the conventional combination of local heating and centralized power plants. CHP plants are used to generate electrical energy and usable heat. In particular, CHP plants are preferably operated on-site or near the usable heat sink. Combustion engines, such as diesel or gasoline engines, Stirling engines, steam engines, combustion turbines, or steam engines, can be used to power the power generator.

[0003] With regard to CHP plants, the use of steam engines in particular has recently gained interest. This is primarily due to the achievable high overall efficiency combined with low pollutant emissions and the almost unlimited choice of liquid or solid fuel, such as wood, pellets, biogas, or biomass. This high efficiency can be achieved with steam pressures of 40 bar to 150 bar and steam temperatures of approximately 300 to 600 °C. Due to these advantages, steam engines are also used in smaller biomass power generation plants, waste heat power plants, waste incineration plants, and thermal oxidizers.

[0004] However, known steam engines, such as the one described in WO 2016 / 146159 A1, which are used particularly for power generation, have the disadvantage of relatively high leakage, for example, during cold starts. This is primarily due to the fact that the steam injected into the steam engine (superheated steam or live steam) is injected into the piston chamber at a pressure of 40 bar to 150 bar in a relatively short time and remains there for a long time. This places high demands on the piston ring seal, which separates the steam from the lubricating oil in the crankshaft chamber or oil pan.

[0005] To counteract this, for example, a four-cylinder steam engine is injected with approximately 1 liter of oil per minute to seal the engine and suppress a "blow-by effect" that would otherwise occur due to the high steam pressure. The oil is injected between the piston and the cylinder wall. Due to the reduction in pressure in the piston chamber to approximately 0.15 bar, a strong suction force is created, so that the oil injected for sealing mixes with the expanded steam and is expelled with it.

[0006] The steam engine is generally followed by a condenser, which condenses the steam and feeds it to a circulation pump, particularly a piston pump, which feeds the condensed water, which, as previously described, may contain a large proportion of oil, to a feedwater tank to provide the condensed water to a steam generator for generating the required superheated steam or live steam for operating the steam engine. However, since the oil contained in the condensed water can lead to water degradation and, due to the high temperature in the steam generator, particularly of the superheated steam generated, to undesirable deposits, it is necessary to separate the oil from the condensed water using an oil separator. For this reason, an oil separator or a device for separating oil and water is usually provided between the condenser and the feedwater tank.This is also necessary in order to recover the large quantities of oil contained in the condensed steam and to feed them back into the steam engine.

[0007] Conventionally, centrifugal separators are used for this purpose. However, due to the wide temperature range of the CHP plant, especially the oil, and the associated fluctuating viscosity of the oil and the fluctuating proportion of oil in the water, these do not provide satisfactory separation or separation performance across the entire operating range of the CHP plant. This can lead, for example, to bearing damage if the required oil pressure cannot be achieved due to the high water content in the oil.

[0008] Further related techniques can be found in US 2 122 310 A, which relates to an oil and water separator comprising a housing with a plurality of chambers stacked vertically one on top of the other. The individual chambers are separated from one another by funnel-shaped baffles, wherein the baffles each have a perforated area with small perforations for the passage of an oil emulsion with a tendency to separate water and oil, wherein the perforated areas are arranged alternately on opposite sides so that the oil emulsion flows upwards through the separation chambers in a zigzag course. Furthermore, a water retaining wall extending transversely to the baffles through the separation chambers is provided to prevent the separated water from escaping downwards through the perforated area, and in US 1 514 118 A, which describes an oil treatment device with a tank.

[0009] Further devices and methods for separating oil and water are known from US 4 591 433 A, EP 0 148 444 A2, US 4 272 371 A, DE 296 12 694 U1, DE 42 33 480 A1 and US 6 383 367 B1. Subject of the invention

[0010] The invention is based on the object of creating a device for separating oil and water, a method for separating oil and water, and a combined heat and power plant comprising the device for separating oil and water according to the invention, which enable effective separation or separation of the oil from the water, regardless of the temperature of an oil-water mixture and the associated viscosity of the oil, and regardless of the proportion of oil contained in the water. Furthermore, the separation of oil and water should be extremely energy-efficient.

[0011] This object is achieved by a device for separating oil and water according to claim 1 and a method for separating oil and water according to claim 11. Preferred developments of the invention are given in the dependent claims, wherein the subject matter of the claims relating to the device for separating oil and water can be used within the framework of the method for separating oil and water and vice versa.

[0012] One of the basic ideas of the present disclosure is that an oil-water mixture is introduced into a housing or a container against gravity, and during an upward flow of the oil-water mixture introduced into the housing or container, the indicated flow is at least partially slowed down by means of a flow brake in order to extend the residence time of the oil-water mixture in the housing or container, thus creating more time for the separation or separation of the oil.

[0013] This makes it possible to achieve effective separation or separation of the oil from the water, regardless of the temperature of an oil-water mixture and the associated viscosity of the oil, and regardless of the proportion of oil contained in the water. Furthermore, since a centrifuge, as in conventional centrifugal separators, is eliminated and separation or separation is achieved solely by gravity, an extremely energy-efficient separation device can be provided.

[0014] According to one aspect, a device for separating oil and water, in particular for separating or separating oil contained in expanded and condensed steam of a steam engine, comprises: a housing, having: an inlet for introducing an oil-water mixture into the housing, an oil outlet for discharging separated or separated oil from the housing, and a water outlet for discharging water (orpurified or largely oil-free water) from the housing, wherein the oil-water mixture can be introduced into the housing in a lower region of the housing with a flow direction that is approximately opposite to gravity, and the housing has a flow brake which the inflowing oil-water mixture has to pass through during an upward flow within a flow path in the housing and thereby at least partially slows it down, wherein the water outlet is arranged in the lower region of the housing, and a limiting plate is provided in the lower region of the housing, which divides an interior of the housing into two regions at least in the lower region of the housing, and is aligned vertically in the housing with a longitudinal extent of the limiting plate, wherein the inlet opens into a first region of the two regions and the water outlet is arranged in the second region.

[0015] In this way, as already described above, it is possible to create an effective and reliable separation or separation of the oil from the water with a sufficient separation effect and purity over a wide temperature range of the oil-water mixture to be separated, whereby high energy consumption can be avoided.

[0016] Using the described limiting plate, it is possible to create two zones. In a first zone, where the plates are arranged, the oil-water mixture introduced into the housing flows slowly upwards and is separated into its water and oil components. During the separation of the oil-water mixture, the separated oil rises due to its lower density, whereas the water sinks due to its higher density, thus resulting in separation. The separated water sinks down alongside the upwardly flowing oil-water mixture. The limiting plate is provided to prevent further mixing with the oil-water mixture, with the heavier water sinking towards the water outlet in the second zone formed by the limiting plate.

[0017] In the context of the present disclosure, "separating or separating" means that the two components bound in the oil-water mixture, oil and water, are separated from one another, regardless of their proportions. In the present invention, the separation takes place by means of gravity, which utilizes the different densities of the two components, oil and water. This means that due to the lower density of the oil, it floats on the heavy water (higher density). An interface is formed, with only oil present above the interface and primarily oil-free water below the interface.

[0018] Furthermore, in the context of the present invention, “braking” or braking means that at least a portion of the oil-water mixture introduced into the housing, preferably the entire oil-water mixture, must flow past or through the flow brake, whereby the flow velocity of the oil-water mixture flowing upwards in the housing is braked or reduced.

[0019] Furthermore, it is preferred if the flow brake is formed from at least one plate (e.g. flow brake plate) with a plurality of through holes (or openings), in particular a plurality of bores, through which the oil-water mixture can flow.

[0020] Using plates, especially perforated plates, it is easy to create an adjustable flow resistance. The flow resistance that can be generated can be adjusted by varying the number of flow-reducing plates provided in the flow path of the oil-water mixture, as well as the number and size / area of the through holes (or openings) in the flow-reducing plate.

[0021] For the purposes of the present disclosure, the “generable flow resistance” is understood to mean that the oil-water mixture must flow through the through-openings in the plate(s) and that, due to the relatively small cross-section of the through-openings or the small number of through-openings, the flow is slowed down, thus generating a flow resistance.

[0022] According to a further embodiment of the present invention, the plate is arranged in the flow path of the introduced oil-water mixture such that the flow cross sections of the plurality of through-holes are oriented approximately perpendicular to the force of gravity. Thus, the center axes of the through-holes run substantially parallel to the force of gravity.

[0023] In this way, maximum flow permeability, i.e., low flow resistance, is achieved for the through holes (or openings) in the plates. On the other hand, for the areas on the flow-reducing plates where no through holes (or openings) are provided, the flow resistance is maximized because the flow of the oil-water mixture impinges perpendicularly on the flow-reducing plates. Compared to the total area of the plates or the section of the flow path blocked by the plates, the cross-sectional area of the flow path is thus reduced, thereby slowing the flow.

[0024] It is also possible to provide through-holes on different plates in such a way that they are not aligned in the direction of flow. This means that the through-holes of successively arranged plates are offset from each other transversely to the direction of flow. This can further increase the flow resistance.

[0025] Furthermore, it is advantageous that a number of plates and / or an area (or size) (cross-sectional area perpendicular to the flow direction) of the through holes, in particular a diameter of the bores, is determined taking into account a temperature range of the oil-water mixture, in particular a viscosity range of the oil bound in the feedable oil-water mixture.

[0026] In this way, the flow resistance can be adapted to the existing oil-water mixture and its temperature range. This is particularly important with regard to a cold start of the system, since during a cold start the temperature of the oil-water mixture is relatively low and thus the viscosity of the oil is relatively high. Furthermore, during the warm-up phase, the oil content in the oil-water mixture is relatively high, which further increases the viscosity of the oil-water mixture.

[0027] In this regard, experiments have shown that the provision of several plates with larger through-holes is advantageous in terms of the achievable results, in particular the achievable separation performance, compared to a smaller number of plates with smaller through-holes.

[0028] According to a further embodiment, at least three plates are arranged in the flow path, wherein the plates preferably have a plurality of bores with a diameter of 1 mm to 25 mm, preferably of 3 mm to 15 mm and more preferably of 5 to 10 mm.

[0029] Furthermore, it is preferable to provide the plates only in a lower region, particularly in a lower third, of the housing, particularly near the inlet for the oil-water mixture. This allows the flow velocity of the oil-water mixture to be quickly slowed down over a short flow path, leaving sufficient space and thus time for the actual separation or separation of the oil from the water.

[0030] Furthermore, it is advantageous for the oil outlet to have a funnel connected to a pipe and arranged in the housing. The pipe preferably connects an outer side of the housing to an inner side of the housing, so that the separated or separated oil can be discharged to the outside. The pipe can preferably be curved for this purpose.

[0031] Furthermore, it is preferred that the funnel is arranged such that an inlet side of the funnel (top edge or inlet edge of the funnel) is oriented approximately opposite to the force of gravity.

[0032] The funnel makes it possible to extract oil, particularly from the upper area of the housing or container where the lighter oil has accumulated. This prevents oil that still contains small amounts of water from being extracted.

[0033] Furthermore, it is preferred that the inlet is formed from a tube, in particular a curved tube, which is arranged in a lower region of the housing, in particular a side wall of the housing. The tube preferably connects an outer side of the housing to an inner side of the housing in order to be able to introduce the oil-water mixture into the housing. It is further preferred that a central axis of an outlet opening of the inlet runs approximately parallel to the force of gravity.

[0034] In this way, the distance between the inlet for the oil-water mixture and the funnel where the separated oil is skimmed off is maximized, which can increase or improve the residence time of the oil-water mixture in the housing and the associated separation performance.

[0035] Furthermore, water (or pure water) can be fed into the housing via the inlet. This way, by adding or draining water, it can be ensured that only oil is present in the area of the funnel inlet or at the top edge of the funnel.

[0036] Furthermore, a sensor can be provided which detects an interface between water and oil, or between an oil-water mixture and oil only, whereby the supply or discharge of water is controlled on the basis of the sensor result.

[0037] According to a further embodiment of the present invention, the water outlet is arranged on a side wall of the housing opposite a side wall of the housing on which the inlet is provided. This allows the water to be discharged from the housing at the lowest point, which can be assumed to ensure maximum water purity.

[0038] The lower area of the housing, in which the limiting plate is arranged, is at least part of the flow path Furthermore, it is advantageous if the device has a heating device, in particular a steam heater, for heating the oil-water mixture introduced into the housing, wherein in particular process heat can be used to heat the oil-water mixture.

[0039] In this way, it is possible, especially during a cold start of the system, to heat the supplied oil-water mixture, which can reduce the viscosity of the mixture and thus increase the separation performance of the device or reach its normal value more quickly.

[0040] Furthermore, it is preferred that the housing is made of stainless steel, in particular stainless steel, and is fluid-tight at least in the lower region, which is designed to receive or be able to receive the oil-water mixture.

[0041] Furthermore, it may be advantageous to provide an adjustment device for the size of the openings or holes. Such an adjustment device can be implemented by respective pairs of flow-reducing plates, wherein the individual plates are provided with congruent through-holes or bores. By moving the plates relative to one another, the congruent openings are shifted relative to one another, thus changing the resulting flow cross-section.

[0042] In this way, during a cold start of the system, when the viscosity of the oil-water mixture is relatively high, the flow cross-section can be maximized, thereby reducing the generable flow resistance. On the other hand, during normal operation, when the viscosity is lower, the flow cross-section can be reduced, thereby increasing the generable flow resistance. This makes it possible to optimally adapt the generable flow resistance to the prevailing conditions.

[0043] Furthermore, it may be advantageous to construct the oil-water separation device in a cascaded manner. This means connecting several oil-water separation devices as described above in series, which means that the individual devices require a lower separation capacity and / or can process a larger amount of oil-water mixture.

[0044] This makes it possible to better adapt the individual devices to the properties of the respective oil-water mixture being fed in, thus increasing the separation performance of the individual devices for separating oil and water. Furthermore, cascading can achieve higher oil purity.

[0045] It is also conceivable to equip the individual devices with a sensor that detects or measures the purity of the oil, i.e., the number of water particles present in the oil. Based on the detection result, it can be determined whether further separation by a downstream device for separating oil and water is necessary.

[0046] Furthermore, it is advantageous to provide a vacuum dewatering device, to which, in particular, the oil discharged through the oil outlet and already separated from the oil-water mixture is fed. In the case of a cascading device for separating oil and water, the vacuum dewatering device is arranged downstream of the last device for separating oil and water in a processing direction of the oil-water mixture, since the highest degree of oil purity can be achieved using the vacuum dewatering device.

[0047] According to one aspect of the present disclosure, the vacuum dewatering device comprises: a preferably longitudinal, in particular cylindrical, vacuum housing which extends in the direction of gravity, i.e. vertically, a vacuum connection which is provided at an upper end of the vacuum housing, wherein the vacuum connection is preferably configured to cause a tangential suction flow in the vacuum housing, an inlet for introducing an oil-water mixture, in particular the oil discharged from the housing of the device for separating oil and water, which inlet is provided at a lower end of the vacuum housing, and an oil outlet which is also provided at the lower end of the vacuum housing, in particular in a bottom of the vacuum housing.

[0048] Furthermore, the inlet is designed as a tube which preferably projects centrally into the vacuum housing, in particular projects into the vacuum housing to approximately 2 / 3 of a total length of the vacuum housing, more preferably projects into the vacuum housing to approximately 2 / 3 of a total length of the longitudinal, in particular cylindrical, vacuum housing.

[0049] Furthermore, the end of the tube that extends into the vacuum housing is open, allowing the oil-water mixture to be introduced into the vacuum housing. Furthermore, shielding plates are provided above the tube and within the vacuum housing to prevent direct fluid flow from the open end of the tube to the vacuum connection. This prevents oil from being sucked in through the vacuum connection.

[0050] Furthermore, drip plates are arranged concentrically around the tube at specific intervals to collect the oil that enters the vacuum housing and foams upon entering the vacuum. The oil collected on the drip plates slowly flows downwards and is discharged through the oil outlet.

[0051] Furthermore, it is advantageous to provide activated carbon filters, which can be used to purify the water freed from oil. It is also preferable to connect several activated carbon filters in series, which makes it possible, when an activated carbon filter becomes clogged, to insert another activated carbon filter located further or further upstream in the direction of water flow and to replace the clogged activated carbon filter without interrupting the purification process.

[0052] Furthermore, the present invention relates to a method for separating oil and water, in particular for separating or separating oil contained in expanded and condensed steam of a steam engine, wherein preferably the device described above is used, comprising the steps: - Introducing an oil-water mixture into a lower region of a housing so that the oil-water mixture flows upwards along a flow path in the housing, wherein a flow direction is approximately opposite to the force of gravity, - at least partially slowing down the upward flow of the introduced oil-water mixture within the casing, and - Separating or separating oil bound in the oil-water mixture, wherein the oil-water mixture is introduced into a first lower region of the housing, which is separated from a second region by a boundary plate, and discharging the separated or separated water through a water outlet arranged in the second region.

[0053] Using the described method, it is possible to achieve effective separation or separation of the oil from the water, regardless of the temperature of an oil-water mixture and the associated viscosity of the oil, and regardless of the proportion of oil contained in the water. Furthermore, since a centrifuge, as in conventional centrifugal separators, is dispensed with and separation or separation is achieved solely by gravity, an extremely energy-efficient separation device can be provided. Effective separation or separation means that a sufficient separation efficiency or purity of the two separated components, oil and water, can be achieved.

[0054] According to one embodiment of the method, in order to slow down the upward flow of the introduced oil-water mixture, the flow is directed through through holes (or openings) provided in at least one plate.

[0055] Furthermore, it is preferred that the separation or separation of the oil from / from the oil-water mixture is achieved by the prevailing weight force, accordingly the oil, which has a lower density than the water, is collected in an upper region of the housing and the water, which has a higher density than the water, is collected in a lower region of the housing.

[0056] Furthermore, it is advantageous if the viscosity of the oil-water mixture is detected, in particular by means of sensors, and based on the detected viscosity of the oil-water mixture, a residence time of the oil-water mixture, in particular of the oil-water mixture in the housing of the device, is controlled.

[0057] The viscosity of the oil-water mixture can be measured using a viscometer in the housing inlet. The residence time of the oil-water mixture in the housing (or in the flow path) can be controlled using the adjustment device described above. For example, the adjustment device can be used to change the total area of the through-holes of individual or all plates, i.e., to increase or decrease their size, or to pivot entire plates into or out of the flow path. In other words, a plate can be pivoted in the flow path such that the cross-sectional area of the through-holes is no longer perpendicular to gravity, but parallel to it. In this way, the flow resistance that can be generated can be drastically reduced.

[0058] Consequently, it is possible to control the residence time of the oil-water mixture in the housing and the associated quality of the separation of the mixture or to adapt it to given conditions and thus to optimize it.

[0059] The described method has the advantages already described with regard to the device for separating oil and water. Individual features of the device for separating oil and water can be used within the method.

[0060] Furthermore, the present invention relates to a combined heat and power plant comprising a steam generator, a steam engine, a condenser and the device for separating oil and water described above. Short description of the drawings Fig. 1 shows a schematic diagram of a combined heat and power plant, Fig. 2 shows a schematic perspective view of an apparatus for separating oil and water according to an embodiment, Fig. 3 shows a detailed view of the Fig. 2 shown device, and Fig. 4 shows a schematic cross-sectional view of a vacuum dewatering device according to an embodiment from the front. Detailed description of the preferred embodiments

[0061] Preferred embodiments of the present invention are described in detail below with reference to the accompanying figures. Further modifications of specific features mentioned in this context can each be combined individually to form further embodiments.

[0062] In the various figures, identical or corresponding elements are designated by the same or similar reference numerals.

[0063] Fig. Figure 1 shows a schematic diagram of a combined heat and power (CHP) plant. The CHP plant 100 shown consists of a steam generator 110, which is connected via a valve 180 to an inlet of a steam engine 120, which drives a generator 130 to generate electricity.

[0064] As already explained above, for the fine sealing of the steam engine 120, it is necessary to supply it with a relatively large amount of oil, which, however, mixes with the expanded steam during operation of the steam engine 120 and is expelled with it. For this reason, the expanded steam expelled by the steam engine 120 contains oil.

[0065] The steam engine 120 is followed by a condenser 150 for condensing the expanded steam, which has a pressure of approximately 0.15 bar and a temperature of approximately 55°C when it leaves the steam engine 120.

[0066] The condensed steam, which still contains a large proportion of oil, is fed to or sucked into a circulation pump 170, in particular a piston pump, via a water column 190, which increases the pressure of the condensed steam to approximately 0.25 bar. The circulation pump increases the pressure of the condensed steam or the now existing oil-water mixture to approximately 1.50 bar and conveys the oil-water mixture to a device 140 for separating oil and water, which corresponds to the device 1 for separating oil and water described below.

[0067] Again Fig. 1 can also be removed, the separated or separated oil is led back to a crankshaft chamber of the steam engine or to a catch tank or injected into the steam engine for fine sealing and the purified water is led to a feed water tank 160, which makes the treated or purified water available to the steam generator 110 again for steam generation, thus closing the circuit.

[0068] Fig. Figure 2 shows a schematic perspective view of an apparatus for separating oil and water according to an embodiment of the present invention. Fig. 2, the device shown has a housing 10, comprising: an inlet 11 for introducing an oil-water mixture into the housing 10, an oil outlet 12 for discharging separated or separated oil from the housing 10, and a water outlet 13 for discharging purified water from the housing 10.

[0069] Again Fig. 2 can also be removed, the oil-water mixture is drawn from a lower area of the housing 10, in Fig. 2 from the bottom left, with a flow direction S which is approximately opposite to gravity, into the housing 10, whereby the introduced oil-water mixture flows from below in the direction of the oil outlet 12, in particular a funnel 12b.

[0070] As shown, the housing 10 is divided into two sections by a boundary plate 40 in a lower region of the housing 10. Between a side wall 10a and the boundary plate 40, three plates 21 are provided horizontally, forming a flow brake 20.

[0071] Fig. 3 shows a detailed view of the Fig. 2 shown device 1. The Fig. 3 is only used to better illustrate the flow brake 20. As the Fig. As can be seen from Figure 3, the flow brake 20 consists of three plates 21, in particular three perforated plates. In the embodiment shown here, the through holes 22 of the plates 21 are designed as bores or circular holes, which makes the production of the plates 21 extremely favorable.

[0072] As further stated in Fig. 3, the inlet 11 is formed by a curved pipe which enters the housing 10 horizontally at a side wall 10a of the housing 10 and is curved upwards, whereby a central axis of an outlet opening of the inlet 11 is parallel to the force of gravity and the outlet opening is directed upwards, whereby the introduced oil-water mixture in Fig. 3 flows upwards. The oil outlet 12 (in Fig. 2) is designed in the form of a snorkel and can be formed from a curved tube 12a and a funnel 12b, wherein the funnel 12b is arranged in the housing 10 such that a funnel upper edge or a funnel inlet runs horizontally and in Fig. 2 is directed upwards, whereby the oil is sucked or “snorkelled” into the funnel 12b from above.

[0073] If an oil-water mixture is now introduced into the device 1 for separating oil and water via the inlet 11, an upward flow is created, supported by the pipe routing of the curved pipe of the inlet 11, which moves along the flow direction S from the inlet 11 towards the oil outlet 12. The flow brake 20 slows down the oil-water mixture flowing in through the inlet 11, thereby increasing the residence time of the oil-water mixture in the housing 10, i.e. before the flow reaches the funnel 12b arranged at the top of the oil outlet 12. It is advantageous here for the flow brake 20 to be configured such that in the upper region of the housing 10, in particular in an upper third of the housing 10, in which the housing is largely filled with oil, the flow velocity of the oil-water mixture tends towards zero.In other words, the flow velocity in the upper area of the housing is extremely low, allowing the oil-water mixture to separate. Accordingly, from the bottom to the top of the housing, the proportion of water in the oil-water mixture decreases and the proportion of oil increases.

[0074] Due to gravity, as described above, the heavier water separates from the lighter oil. Accordingly, on its way to the oil outlet 12, the heavier water begins to separate from the upwardly flowing oil-water mixture and sink downward. In this way, the oil-water mixture is continuously separated into its components, and ultimately, only oil reaches the top of the funnel 12b. On the other hand, only the sinking heavier water reaches the water outlet 13.

[0075] In order to ensure that an oil surface of the oil-water mixture held in the housing 10 is always above the upper edge of the funnel 12, and further to ensure that a boundary layer between oil and oil-water mixture is below the upper edge of the funnel, thus ensuring that only pure oil reaches the funnel 12, it is necessary to control the amount of fluid flowing into the housing 10 (oil-water mixture) and fluid flowing out of the housing 10 (oil + water) using a control system.

[0076] For this purpose, a sensor is provided in the housing 10, which detects the boundary layer between the oil and the oil-water mixture, and based on the sensor result, the supply or discharge of water is controlled. This means that if the sensor detects that there is a tendency for the oil surface of the oil-water mixture to move below the upper edge of the funnel, the amount of water discharged through the water outlet 13 is reduced in a first step. However, if the amount of water discharged cannot be reduced further because more water is required by downstream components, such as the steam generator 110, additional water is supplied to the oil-water mixture before it enters the inlet 11, whereby the amount of inflowing fluid can be increased and the sinking oil surface can thus be counteracted.

[0077] On the other hand, if the sensor detects that the boundary layer between oil and oil-water mixture is moving upwards towards the top edge of the funnel, which poses the risk of unwanted water being sucked into the oil outlet, the amount of water discharged through the water outlet 13 can be increased or the amount of oil-water mixture, in particular water, introduced into the housing 10 can be reduced. Furthermore, Fig. 4 is a schematic cross-sectional front view of a vacuum dewatering device according to an embodiment of the present disclosure. Fig. 4, the vacuum dewatering device 50 comprises: a cylindrical vacuum housing 51 which extends in the direction of gravity, a vacuum port 52 which is provided at an upper end of the cylindrical vacuum housing 51, the vacuum port 52 being arranged to cause a tangential suction flow in the vacuum housing 51, an inlet 53 for introducing an oil-water mixture, in particular the oil discharged from the housing 10 of the device 1 for separating oil and water, which inlet is provided at a lower end of the cylindrical vacuum housing 51, and an oil outlet 54 which is provided at the lower end of the vacuum housing 51 and from which the dewatered oil is discharged.

[0078] Furthermore, the Fig.4 that the inlet is designed as a tube 53 which projects centrally into the cylindrical vacuum housing 51 parallel to the direction of gravity, in particular projects into the vacuum housing 51 to approximately 2 / 3 of the total length of the latter.

[0079] Furthermore, the end of tube 53 extending into vacuum housing 51 is open, allowing the oil-water mixture to be introduced into the vacuum housing. Furthermore, shielding plates 56 are provided above tube 53 and within vacuum housing 51, preventing direct fluid flow from the open end of tube 53 to vacuum port 52. This prevents oil from being sucked in through vacuum port 52 and contaminating the extracted water.

[0080] Furthermore, drip plates 55 are arranged concentrically around the tube 53 at specific intervals. These drip plates serve to collect the oil Ö introduced into the vacuum housing 51, which foams upon entering the vacuum. The oil Ö collected on the drip plates 55 flows slowly downward and is discharged through the oil outlet 54.

[0081] If oil Ö with a certain proportion of water, in particular a small proportion of water, is now introduced through the pipe 53 or the inlet pipe, the oil Ö foams up at the open end of the pipe due to the low pressure or negative pressure (vacuum) prevailing in the vacuum housing 51, whereby the water W contained in the oil Ö is separated and can be sucked out through the vacuum connection 52. In order to prevent a portion of the foamed oil Ö from being sucked in through the vacuum connection 52, shielding plates 56 are provided between the vacuum connection, which is provided tangentially on the vacuum housing 51, and the open end of the pipe 53. In this way, a direct fluid connection between the vacuum connection 52 and the open end of the pipe 53 is prevented and prevents oil from being sucked out along with the sucked-out water W.

[0082] Due to gravity and the drip plates 55 provided in the cylindrical vacuum housing 51, the oil foam sinking downwards slowly condenses again into oil oil and can be discharged through the oil outlet 54 as oil purified from water.

[0083] From the foregoing description, those skilled in the art will recognize that various modifications and variations of the apparatus and method of the invention can be made without departing from the scope of the invention.

[0084] Furthermore, the invention has been described with reference to specific embodiments, which are intended only to provide a better understanding of the invention and are not intended to be limiting. Those skilled in the art will also readily recognize that many different combinations of the elements may be used to practice the present invention. Therefore, the scope of the invention is indicated by the following claims.

Claims

[1] Device (1) for separating oil and water, comprising: a housing (10) comprising: an inlet (11) for introducing an oil-water mixture into the housing (10), an oil outlet (12) for discharging separated or separated oil from the housing (10), and a water outlet (13) to drain water from the housing (10), wherein the inlet (11) is provided in a lower region of the housing (10), so that the oil-water mixture can be introduced from the lower region into the housing (10) and can flow upwards along a flow path (30) with a flow direction (S) which is opposite to the force of gravity, and the housing (10) has a flow brake (20) in the flow path (30), which is to be passed by the oil-water mixture during the upward flow and thereby brakes the upward flow, characterized by , that the water outlet is arranged in the lower part of the housing (10), and in the lower region of the housing, a limiting plate is provided which divides an interior of the housing into two regions at least in the lower region of the housing, and is aligned with a longitudinal extent of the limiting plate (40) vertically in the housing (10), wherein the inlet opens into a first area of the two areas and the water outlet is arranged in the second area. [2] Device (1) according to claim 1, wherein the flow brake (20) is formed from at least one plate (21) which at least partially blocks the flow path (30) and is provided with a plurality of through holes (22) through which the oil-water mixture can flow. [3] Device (1) according to claim 2, wherein the plate (21) is arranged in the flow path (30) such that flow cross sections of the plurality of through holes (22) are oriented perpendicular to gravity. [4] Device (1) according to one of claims 2 or 3, wherein a number of the flow brake plates (21) and / or an area of the through holes (22), in particular their diameter, is / are determined taking into account a temperature range of the feedable oil-water mixture, in particular a viscosity range of the oil bound in the feedable oil-water mixture, wherein preferably at least three of the plates (21) are arranged in the flow path (30). [5] Device (1) according to one of the preceding claims, wherein the oil outlet (12) comprises a funnel (12b) connected to a pipe (12a) and arranged in the housing (10), wherein the funnel (12) is preferably arranged such that an inlet side of the funnel (12b) is oriented opposite to the force of gravity. [6] Device (1) according to one of the preceding claims, wherein the inlet (11) is formed from a tube (11a) which is arranged in a lower region of the housing (10), in particular a side wall (10a) of the housing (10), wherein the tube (11a) preferably connects an outer side of the housing (10) to an inner side of the housing (10) in order to be able to introduce the oil-water mixture into the housing (10). [7] Device (1) according to one of the preceding claims, wherein the water outlet (13) is arranged on a side wall (10b) of the housing (10) which is opposite the side wall (10a) of the housing (10) on which the inlet (11) is provided. [8] Device (1) according to one of the preceding claims, further comprising a heating device, in particular a steam heater, for heating the oil-water mixture introduced into the housing (10). [9] Device (1) according to one of the preceding claims, wherein the housing (10) is made of stainless steel, in particular stainless steel, and is fluid-tight at least in the lower region, which is designed to receive the oil-water mixture. [10] Device (1) according to one of the preceding claims, further comprising a vacuum dewatering device (50) comprising: a vacuum housing (51) which extends in the direction of gravity and is preferably longitudinally shaped, in particular cylindrical, a vacuum connection (52) provided at an upper end of the vacuum housing (51), wherein the vacuum connection (52) is preferably arranged to cause a tangential suction flow in the vacuum housing (51), an inlet (53) for introducing an oil-water mixture, in particular the oil discharged from the housing (10) of the device (1) for separating oil and water, which is provided at a lower end of the vacuum housing (51), and an oil outlet (54) provided at the lower end of the vacuum housing (51). [11] A method for separating oil and water, using the device (1) according to any one of the preceding claims, comprising the steps: - introducing an oil-water mixture into a lower region of a housing (10) so that the oil-water mixture flows upwards along a flow path in the housing, wherein a flow direction (S) is opposite to the force of gravity, - at least partially slowing down the upward flow of the introduced oil-water mixture, and - Separating or separating oil bound in the oil-water mixture, wherein the oil-water mixture is introduced into a first lower region of the housing, which is separated from a second region by a boundary plate, and discharging the separated or separated water through a water outlet arranged in the second region. [12] Method according to claim 11, wherein, in order to brake the upward flow of the introduced oil-water mixture, the flow is directed through through holes (22) provided in at least one plate (21). [13] Method according to claim 11 or 12, wherein the separation or separation of the oil from / from the oil-water mixture is achieved by the prevailing weight force, accordingly the oil, which has a lower density than the water, is collected in an upper region of the housing (10) and the water, which has a higher density than the oil, is collected in a lower region of the housing. [14] Method according to one of claims 11 to 13, in which the viscosity of the oil-water mixture is detected, in particular by means of sensors, and based on the detected viscosity, a residence time of the oil-water mixture, in particular of the oil-water mixture in the housing (10), is controlled.

Images