PHASE SEPARATOR

Description

[0001] The invention relates to a phase separation device having the features in the preamble of claim 1.

[0002] DE 10 2016 006 509 A1 discloses a filter device for fluids, comprising a housing accommodating at least one filter element, which has an inlet for supplying the fluid to be cleaned to an unfiltered fluid chamber of the housing, which is separated by the filter medium of the respective filter element from a filtrate chamber of the housing, which filtrate chamber has a filtrate outlet. In this way, the particulate contamination is filtered out of the fluid flow by means of the filter element in a type of phase separation. Furthermore, the known filter device comprises a magnetic field-generating device arranged within the unfiltered fluid chamber, which has an adhesion surface for ferromagnetic particles deposited thereon by magnetic force, which are thus separated from the fluid flow as a further phase during the phase separation.

[0003] Furthermore, the separation of multiphase fluids, such as dispersions and emulsions, by means of coalescence is state of the art. A widespread technical application is the separation of the aqueous phase as an additive in oils or fuels by means of the coalescence effect, resulting in the coalescence of colloidal particles, such as the formation of water droplets as the aqueous phase to be removed. The known phase separation devices available on the market reach their limits in terms of efficiency, particularly in the separation of tramp oils with a finely dispersed oil phase, for example, in the separation of oils such as machining oils, hydraulic oils, cutting oils, and the like.

[0004] US 2018 / 0056212 A1 describes a phase separation device with the features in the preamble of claim 1, comprising a first device housing accommodating at least one coalescing element, which has an inlet for the supply of an emulsion that flows through the respective coalescing element to separate it into at least two of its components; an outlet for a separated component;and has a further outlet for a further separated component which floats on the one component with a lower density than the first component, wherein a combination of a coalescence and a gravity separator is located in the first device housing and a particle filter is arranged in a second device housing, which is connected upstream of the coalescence and gravity separator in the first device housing as a pre-filter, and wherein at least one filter element is used for particle filtration, which is accommodated in the second device housing.;

[0005] Further phase separation devices are disclosed in US Pat. No. 4,058,463 A, US Pat. No. 3,085,690 A, and CA 2,576,634 A1. US Pat. No. 3,016,984 A discloses a gas filter device.

[0006] The invention is based on the object of providing a phase separation device with at least one coalescence stage, which is characterized by a particularly high efficiency in the demixing of emulsions, even in emulsions with a finely dispersed oil phase.

[0007] According to the invention, this object is achieved by a phase separation device which has the features of patent claim 1 in its entirety.

[0008] According to the characterizing part of claim 1, the structure of the second device housing largely corresponds to that of the first device housing and each has a modular housing structure in the form of a closed pressure vessel. The overall device, thus partially formed by identical parts, can thus be manufactured particularly efficiently.

[0009] Accordingly, in a device of the type mentioned above, the invention provides, in addition to the outlet for a separated component, a further outlet for a further separated component, which floats on top of the first component with a lower density than the first component. Thus, a combination of coalescence and gravity separator is formed in the same first device housing. In addition to high separation efficiency, the separated phases are each available in a dedicated outlet, so that the components can be discharged completely separated, for example, in the form of a floating, lighter oil phase at an upper outlet and an aqueous phase at an outlet below.Furthermore, the combination of a coalescence and gravity separator in a single device housing enables a particularly compact device design with smaller bath volumes compared to pure gravity separators, resulting in lower exchange volumes during bath changes. Low heat losses due to a comparatively small housing surface also enable high energy efficiency.

[0010] Advantageously, the arrangement is such that the inlet for the emulsion opens into the interior of the respective coalescence element, through which the flow flows from the inside to the outside.

[0011] In advantageous embodiments, the first device housing is formed from an elongated, in particular multi-part, housing shell, seen in the vertical installation direction, which has the inlet for the emulsion and the one outlet for the one separated component on the base side, preferably in the lower third of the housing, and which has the further outlet for the further separated component on the head side, preferably in the upper third of the housing, particularly preferably at the uppermost point of the first device housing.

[0012] Advantageously, the arrangement can be such that the outlet for the one separated component is introduced into the first device housing below an inlet into the coalescence element immediately following this inlet.

[0013] In particularly advantageous embodiments, more volume, preferably more than 1.5 times the volume of the first device housing, is available for the other component than for the single component. This creates a relatively large dead zone above the coalescing element for the low-density component, such as oil, so that the gravitational settling of the lighter phase, such as oil, is particularly favored.

[0014] Advantageously, the outlet for the further separated component, such as oil, can be provided with a valve device and / or a venting device. Degassing by the venting device leads to the settling of the lighter phase, such as the oil phase, and the presence of the valve device enables automatic discharge of the lighter phase, for example, by means of a timer.

[0015] Advantageously, at least some of the coalescence elements used can be equipped with a filtration stage as part of the element. In addition to the coalescence separation, maintenance filtration can thus take place in the same element.

[0016] In particularly advantageous embodiments, at least some of the coalescence elements used are provided with at least one additional support shell on the outer circumference in the downstream direction, which preferably promotes the droplet growth of the separated component through adsorption. The support shell can advantageously be made of stainless steel and, if appropriate, be graduated in multiple layers.

[0017] In this regard, the arrangement can advantageously be such that the respective filtration stage and / or the respective coalescence element is accommodated in the fluid-permeable support casing, which has at least two casing parts which can be folded by means of an associated hinge and which, in a folded-open position, enable the respective used element to be exchanged for a new element.

[0018] For fluids that are to be demixed and are loaded with contaminants, the emulsion preferably undergoes particle filtration before its phase separation.

[0019] For particle filtration, the respective filter element can be flowed through from the outside to the inside, with the filtrate outlet of the second device housing being connected to the inlet of the adjacent first device housing via a connection point. The connection point can be formed by flanged pipes.

[0020] The invention is particularly advantageously suitable for demixing an emulsion in the form of a water-oil mixture, wherein one component to be separated is water and the other component to be separated is a hydraulic medium, such as oil.

[0021] According to claim 12, the invention also relates to the use of a phase separation device according to one of claims 1 to 11 for demixing multiphase media.

[0022] The invention is explained in detail below with reference to exemplary embodiments illustrated in the drawings. They show: Fig. 1 shows a schematically simplified longitudinal section of an embodiment of the phase separation device according to the invention; Fig. 2 shows one of the Fig. 1 corresponding representation of a second embodiment, wherein the element materials of a coalescence element and particle filters are omitted; Fig. 3 one of the Fig. 2 corresponding representation of a third embodiment with a support casing located on the outside of the coalescing element; Fig. 4 shows a longitudinal section of a separately illustrated coalescing element; and Fig. 5 shows a perspective oblique view of the separately illustrated support casing for the coalescing element.

[0023] With reference to the accompanying drawings, the invention is described using exemplary embodiments in which a combination of a coalescing and a gravity separator is located in a first device housing 2, and a particle filter is arranged in a second device housing 4, which acts as a pre-filter upstream of the coalescing and gravity separator in the first device housing 2. While pre-filtration before demixing in the first device housing 2 is generally required, the particle filter in the second device housing 4 can be omitted if necessary for media that are free of contaminants. Both device housings 2 and 4 have a substantially identical, modular housing structure in the form of a closed pressure vessel.In both housings 2 and 4, this comprises an upper housing section 6, a middle housing section 8, and a lower housing section 10, which are circular cylindrical, have the same diameter, and are connected to one another via flanges 12. The lower housing sections 10 each have a curved bottom 14 that is closed except for a drain screw 16. The upper housing sections 6, which, like the lower housing sections 10, are manufactured by deep drawing in a cup-drawing process, have a curved upper end 18, corresponding to the curved bottom 14 of the lower sections 10. In the second device housing 4, this is closed by a centrally located vent screw 20, while a centrally located outlet connection 22 is located at the end 18 of the first device housing 2.

[0024] For pre-filtration, two filter elements 24 are provided in the second device housing 4. These are arranged coaxially one above the other and are connected to one another at one of their end caps 26 in such a way that their inner filter cavities merge seamlessly into one another. The upper filter element 24 is closed at its upper end cap 26 by a closure cover 28, while a centrally located opening 30 is located on the lower end cap 26 of the lower filter element 24. For pre-filtration, the emulsion flows into the second device housing 4 via an inlet 32, which is located below the lower end cap 26 of the lower filter element 24 on the side wall of the housing base 10 of the second device housing 4.From the interior of the lower housing section 10, the emulsion reaches the intermediate space surrounding the outside of the filter elements 24 in the second device housing 4 and flows through the filter medium of the filter elements 24 from the outside inward to the clean-side interior of the filter elements 24. A pipe bend 34 is connected to the central opening 30 of the lower end cap 26 of the lower filter element 24, through which the pre-filtered filtrate leaves the lower housing section 10. The pipe bend 34 is connected via a connecting flange 36 to a pipe bend 38, which extends into the interior of the lower housing section 10 of the first device housing 2. With its end, the pipe bend 38 forms the inlet 40 for supplying the emulsion into the interior of a coalescing element 42 arranged in the first device housing 2. As shown, this inlet 40 is located at a central opening of the lower end cap 44 of the coalescing element 42.As can also be seen from the drawing, the lower end cap 44 with the inlet 40 is located at an axial distance above the bottom 14 of the housing lower part 10 and at an axial distance above a lateral outlet 46 of the housing lower part 10 of the first device housing 2. The upper end cap 48 of the coalescing element 42 is closed by means of a closure cover 50, as is the case with the upper filter element 24 in the second device housing 4.

[0025] During operation, the emulsion to be demixed enters the interior of the coalescing element 42 via the inlet 40 of the lower end cap 44 and flows through its element material 52 from the inside to the outside to the space 54 surrounding the outside of the coalescing element 42 in the first device housing 2. The coalescing stage in the element material 52 results in phase separation by the deposition of an aqueous phase through the growth of drops of aqueous colloids, which accumulate as an aqueous phase 56 in the lower region of the first device housing 2, as well as an overlying oil phase 58. As the Fig. 1 bis 3 can be removed, there is a dead space 60 in the first device housing 2 above the coalescence element 42, which adjoins the oil phase 58 as an oil settling zone 62 and extends to the outlet connection 22 at the upper housing end 8. This axially extended dead space 60, which provides a volume for the lighter oil phase floating on the aqueous phase that is up to 1.5 times greater than the volume of the aqueous phase, promotes highly efficient gravity separation of the lighter phase, such as oil. The connection 22 provided at the upper end of the upper housing section 6 forms the outlet for the separated lighter phase, controlled by an outlet valve 64. An automatic vent 66, which is also connected to the connection 22 and ensures the degassing of the settling zone 62, further promotes the efficiency of the gravity separation by calming the oil phase.In addition to the coalescence stage, the coalescence element 42 may be provided in its element material 52 with a filtration stage which may be designed for maintenance filtration.

[0026] The Fig. 2 shows a modified embodiment that differs from the example of Fig. 1 differs only in that in the second device housing 4, instead of the filter candle formed from two filter elements 24 for particle filtration, only a one-piece filter element 68 is used.

[0027] The embodiment of Fig. 3 corresponds to the example of Fig. 2 , except that the coalescing element 42 is surrounded on the outside of its element material 52 by a support jacket 72, which in Fig. 5 shown separately and as a reusable component around the coalescence element 42, which is Fig. 4 also shown separately. The support casing 72 is made of stainless steel and has a pattern of perforations 74 (in Fig. 5 only partially shown). Due to the high interfacial energy of stainless steel, the jacket 72 also promotes droplet growth in the oil through adsorption on the metal surface. Particularly with a multi-layer, graduated structure of the coalescence stage with increasing porosity in the flow direction, a high separation efficiency can be achieved. Fig. 5 shows, the jacket 72 is formed from foldable jacket parts 76, 78, which can be connected to one another by means of a type of hinge 80, so that the jacket 72 can be used several times.

Claims

1. Phase separation device having a first device housing (2) accommodating at least one coalescing element (42), comprising - an inlet (38) for supplying an emulsion that flows through the respective coalescing element (42) for separation into at least two of its constituents; - an outlet (46) for a separated constituent; and - a further outlet (22, 64) for another separated constituent, which has a lower density than the first constituent and floats on top of said first constituent, wherein a combination of a coalescing separator and a gravity separator is located in the first device housing (2) and a particulate filter is arranged in a second device housing (4), said particulate filter being connected upstream of the coalescing and gravity separator in the first device housing (2) as a pre-filter, and wherein at least one filter element (24, 68) is used for particle filtration, said filter element being accommodated in the second device housing (4), characterised in that the structure of the second device housing (4) corresponds to the greatest possible extent to the structure of the first device housing (2) and in each case has a modular housing structure in the form of a closed pressure vessel.

2. Phase separation device according to claim 1, characterised in that the inlet (38) for the emulsion opens out into the interior of the respective coalescing element (42), through which the flow passes from the inside to the outside.

3. Phase separation device according to either claim 1 or 2, characterised in that the first device housing (2) is formed by an elongated, as viewed in the vertical installation direction, in particular multi-part housing jacket, which comprises the inlet (38) for the emulsion and one outlet (46) for one separated constituent at the bottom, preferably in the lower third of the housing, and comprises the other outlet (22, 64) for the other separated constituent at the top, preferably in the upper third of the housing, more preferably at a position arranged at the very top of the first device housing (2).

4. Phase separation device according to any of the preceding claims, characterised in that the outlet (46) for one separated constituent is placed in the first device housing (2) below an entrance (40) into the coalescing element (42) immediately after the inlet (38).

5. Phase separation device according to any of the preceding claims, characterised in that, with respect to the receiving volume of the first device housing (2), more volume, preferably more than 1.5 times the volume, is available for the other constituent in comparison to the first constituent.

6. Phase separation device according to any of the preceding claims, characterised in that the outlet (22, 64) for the other separated constituent is provided with a valve apparatus (64) and / or with a venting apparatus (66).

7. Phase separation device according to any of the preceding claims, characterised in that at least part of the coalescing elements (42) used is provided with a filtration stage (52) as a component of the element (42).

8. Phase separation device according to any of the preceding claims, characterised in that at least part of the coalescing elements (42) used is provided in the outflow direction on the outer circumference with at least one additional fluid-permeable supporting jacket (72), which preferably favours droplet growth of the one separated constituent by adsorption.

9. Phase separation device according to claim 8, characterised in that the respective filtration stage (52) and / or the respective coalescing element (42) is accommodated in the additional fluid-permeable supporting jacket (72), which has at least two jacket parts (76, 78), which can be folded by means of an assigned hinge (80) and, in an unfolded position, permit the respective used element (42) to be replaced with a new element (42).

10. Phase separation device according to any of the preceding claims, characterised in that the flow passes through the respective filter element (24, 68) from the outside to the inside for particle filtration and the filter outlet (34) of the second device housing (4) is connected via a connection point (36) to the inlet (38) of the adjacently installed first device housing (2).

11. Phase separation device according to any of the preceding claims, characterised in that the emulsion is a water-oil mixture and in that one constituent to be separated is water and the other constituent to be separated is a hydraulic medium, such as oil.

12. Use of a phase separation device according to any of the preceding claims, characterised in that a feed pump is connected to a tank outlet of a storage tank in relation to a hydraulic system, said feed pump conveying emulsion cleaned of particles from the second device housing (4) having the respective filter element (24, 68) to the first device housing (2) having the respective coalescing element (42) during the particle filtration process, said coalescing element conveying the separated oil in the direction of the storage tank in a parallel or series connection to the particle filtration process.