GB2035833A

GB2035833A - Removing liquid particles from gases

Info

Publication number: GB2035833A
Application number: GB7939616A
Authority: GB
Original assignee: VYZK USTAV CHEM ZARIZENI
Current assignee: VYZK USTAV CHEM ZARIZENI
Priority date: 1978-11-15
Filing date: 1979-11-15
Publication date: 1980-06-25
Also published as: GB2035833B; SU902790A1; HU180980B; DE2945798A1; DD148445A3; BG30801A1; CS202112B1

Abstract

Apparatus for separating liquids and liquid aerosols from gases, e.g. deoiling pressurized air intended for inhalation and for turbine-type drilling in dentistry, comprises a vessel 1 and a tube 8 ending into the vessel to provide an annular passage for inflow and a central passage for clean gas outflow, baffle plates in the vessel providing for sinuous inflow through the annular passage to the inner end of the central passage, and a plurality of annular separation layers 4, 5, 6 associated with the baffle plates so that the sinuous inflow passes radially through successive separation layers. Preferably the vessel is of inverted-U cross sectional shape and there are three annular separation layers to separate successively by agglomeration, filtration and adsorption, only precleaned gas reaching the filter e.g. glass fibers and the adsorver e.g. silicagel or activated carbon so that their surfaces do not become polluted. Sealing of the separation layers can be obtained by embedding their upper and lower ends in the radially extending baffle plates. Liquid is discharged through outlet 12. <IMAGE>

Description

SPECIFICATION Improved apparatus for separating gas/liquid mixtures This invention relates to apparatus for separating gas/liquid miixtures and is primarily but not exclusively concerned with the improved three-stage separation of liquids and liquid aerosols from gases arising from the lay-out of the built-in separating section and the ducting of the apparatus.

There presently exists a three-stage liquid separating apparatus consisting of ducting in which three separation stages are located, namely an agglomerator with a cylindrical wall which is radially permeable, below the agglomerator or inside its cavity an adsorber is located and below it is a fillter; the latter two have separation layers which are axially permeable. The gas first passes through the agglomerator and flows downwards along the adsorber and the filter, and from the bottom it gradually rises into the filter and into the adsorber. A gas inlet and a gas outlet are provided in an upper cover on the ducting.

The gas flowing along the adsorber and the filter still contains a great amount of liquid, and severely pollutes the surface of the adsorber and of the filter. When the filling is exchanged, these impurities penetrate into the ducts designed for cleaned gas. This impairs the working of the apparatus. Another drawback of this type of apparatus can be seen in the axially permeable separation layers of the filter and adsorber, which on the one hand have a small through-flow area and, on the other hand, are difficult to seal on the circumference, so that short circuits are produced and the separability is thus impaired.

The object of the present invention is to obviate or mitigate the disadvantages of the existing apparatus.

According to the present invention we provide apparatus for separating a gas/liquid mixture, comprising U-ducting including a vessel and a tube extending into the vessel to provide an annular passage for inflow and a central passage for outflow, baffle means in the vessel providing for sinuous.inflow through the annular passage to the inner end of the central passage, and a plurality of annular separation layers associated with the baffle means so that the sinuous inflow passes radially through successive separation layers.

In a preferred arrangement now described, there are three separation stages viz. an agglomerator, a filter and an adsorber having each a cylindrical annular separation layer permeable in radial direction, and they are inside the vessel and located one above the other in such a way that a hollow extension ring connected to the bottom of the vessel carries the agglomerator whose upper baffle plate is secured to the central tube which is led through the bottom of the vessel. The filter is located above the agglomerator and its lower baffle plate is secured to the central tube, and seated on its upper baffle plate is the lower baffle plate of the adsorber. The upper baffle plate of the adsorber is secured to the central tube.The whole adsorber is housed in a bell, the lower edge of the skirt of which bears on the upper baffle plate of the filter or on the lower baffle plate of the adsorber. In its upper part the bell is closed.

The central tube passes through the central openings of the agglomerator, of the filter and of the adsorber, extending finally into the bell space. Here, above the adsorber, the tube bore opens into the inner space of the bell by at least one opening in the tube wall. Gas is introduced through the bore of the extension ring and is released through the bottom end of the central tube. A liquid outlet is provided in the bottom of the vessel. The upper part of the closed vessel is in the form of a removable cover. It is of advantage to couple together the filter and adsorber to form one unit by means of a connecting sleeve which encloses the central tube and whose upper end is secured to the upper baffle plate of the adsorber.The central tube can with advantage be provided with a shoulder forming a seat against which the lower baffle plate of the filter or the lower edge of the coupling sleeve is pressed with the aid of an upper nut moving along a screw thread on the central tube above the adsorber and pressing the upper baffle plate of the adsorber downwards.

The agglomerator can be pressed against the extension ring by a lower nut moving along a screw thread on the central tube above the agglomerator. The central tube can with advantage extend through the top wall of the bell, and above the bell it can be provided with a screw thread and a closing nut which presses the bell downwards. It is of advantage to have the agglomerator provided on the outside with a permeable annular baffle sheet separated by a gap from the outer surface of the annular agglomeration layer.

An advantage of the three-stage separator described lies in that only precleaned gas reaches the filter and the adsorber, so that their surface does not get polluted. Another feature is that the radial permeation of the separation layers of all the three separating elements ensures a sufficiently large throughflow area and enables an increase in the performance while preserving the outer dimensions of the apparatus. In addition, perfect tightness of the separation layers can be obtained by embedding their upper and lower ends in the opposed baffle plates.

Embodiments of the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 shows a three-stage separator with three separating stages with radially permea ble layers can be seen while Figure 2 shows a separator whose filter is joined with the adsorber.

Referring to the drawings:~ In Fig. 1 a vessel 1 is in its lower part closed with a bottom 3 and in its upper section is in the form of a removable cover 2.

Attached to the bottom 3 is a supporting ring 7 carrying the lower baffle plate of an agglomerator 4 with a radially permeable separation layer. The upper baffle plate of the agglomerator 4 is connected to a central tube 8 which passes through the bottom 3. Above the agglomerator 4 a filter 5 is sleeved onto the central tube 8; the lower baffle plate of the filter is connected to the central tube 8 and its upper baffle plate carries the lower baffle plate of the adsorber so that the cavity of the filter 5 opens into the cavity of the adsorber 6. The upper baffle plate of the adsorber 6 is connected to the central tube 8.

The adsorber 6 is housed in a bell 9 consisting of a skirt whose lower edge rests on the upper baffle plate of the filter 5 and whose upper end is closed. The central tube 8 passes through the upper base of the adsorber 6 into the space below the bell 9, and its cavity is connected with this space.

A gas inlet 10 provided in the bottom 3 leads into the cavity of the ring 7; a gas outlet 11 is provided in the lower end of the central tube 8, and a liquid outlet 12 is formed in the bottom 3, outside the ring 7. The separation layers of the agglomerator 4 can be made e.g.

of pressed fine glass fibres or of wound twocomponent filter textiles held between two concentric cylinders of perforated sheet. The lower and upper baffle plates can be made to form shaped covers into which the end portions of the separation layer are embedded and sealed with synthetic resin. The separation layer of the filter 5 is filled with the finest pressed glass fibres and is supported as in the case of the separation layer of the agglomerator 4. The separation layer of the adsorber 6 is made up of porous material which exhibits sorption properties with respect to vapours of the liquid separated, such as silicagel, activated carbon or filtration paper with a low binder content and a filler possessing sorption properties.

The gas/liquid mixture enters via the inlet 10 the bore of the ring 7 and passes through the separation layer of the agglomerator 4 into the space of the vessel 1. During the passage of the gas through the layer, droplets of liquid are separated out and flow down to the bottom 3; the liquid accumulated is discharged through the outlet 12. In the vessel 1 the precleaned gas flows upwards and passes through the separation layer of the filter 5 and further into its cavity, during which stage the finest particles of liquid are separated out from the gas. The gas flows into the cavity of the adsorber 6 and penetrates through its separation layer into the space of the bell 9.

By now the remaining part of the liquid and most of the vapours are separated out from the gas. Via an opening 13, the gas enters the cavity of the central tube and is discharged via the outlet 11.

In Fig. 2 the central tube 8 is located between the agglomerator 4 and the filter 5, and from this point downwards it widens out and thus forms a seat 17. On the widened part of the central tube 8 a screw thread is cut, with a lower nut 14 pressing the agglomerator against the ring 7. Packing can be inserted between the lower nut 14 and the agglomerator 4. The filter 5 is coupled with the adsorber 6 by means of a connecting sleeve 22 to form an assembly. The filter 5 is seated with its base on a lower packing 18 located on the seat 17. The central tube 8 passes through the top wall of the bell 9, and its upper end is provided with a screw thread which on the portion above the adsorber 6 carries an upper nut 15 clamping the sleeve 22 against the packing 18; above the bell 9 the central tube 8 carries a closing nut 16 which clamps the bell 9 onto the upper baffle plate of the filter 5.An upper packing ring 19 is provided between the closing nut 16 and the bell 9. At its circumference the agglomerator 4 includes an annular permeable baffle wall 20 which is separated by a gap 21 from the separation layer of the agglomerator 4.

The permeable baffle wall can be made of perforated sheet with small perforations and a low gap density, or of a thin layer of filter textiles. The aerodynamic resistance of the permeable baffle wall 20 makes the gas flow radially and at a low speed in the gap 21 so that the agglomerated liquid is separated out completely from the gas.

The three-stage separating apparatus described is mainly designed for highly efficient cleaning of gases for very demanding tasks, such as the deoiling of pressurized air which is intended e.g. for direct inhalation by operators of sand blasting machines, for mixing with oxygen in breathing resuscitation apparatuses, for turbine-type drilling machines in dentistry, and for use in food industry. The conception of the apparatus guarantees a high degree of cleaning efficiency, a small pressure loss, and a long service life.

Claims

1. Apparatus for separating a gas/liquid mixture, comprising U-ducting including a vessel and a tube extending into the vessel to provide an annular passage for inflow and a central passage for outflow, baffle means in the vessel providing for sinuous inflow through the annular passage to the inner end of the central passage, and a plurality of annular separation layers associated with the baffle means so that the sinuous inflow passes radially through successive separation layers.

2. Apparatus according to claim 1, wherein the ducting is of inverted-U form, and three annular layers are disposed in series one above the other in the inflow passage to separate successively by agglomeration, filtration and adsorption.

3. Apparatus according to claim 1, wherein the baffle means include a series of radially extending plates in the inflow passage, and the annular separation layers are disposed between pairs of opposed plates of the series.

4. Apparatus according to claim 3, wherein each separation layer is secured to its pair of opposed plates to form therewith an annular separator, and the annular separators are withdrawably mounted in the annular inflow passage.

5. Apparatus according to claim 4 including a junction sleeve interconnecting the adsorption and filtration separators to form therewith an annular adsorption/filtration assembly.

6. Apparatus according to claim 5, wherein the vessel of the U-ducting includes a floor portion, the agglomeration separator is clamped to a supporting ring on the floor portion by a first nut in screw-threaded engagement with the central tube of the Uducting, the filtration separator of the adsorption/filtration assembly abuts a shoulder on the central tube, and a second nut in screwthreaded engagement with the central tube of the U-ducting engages the adsorption/filtration assembly to effect clamping of the assembly to said shoulder.

7. Apparatus according to claim 6, wherein the baffle means further include a bell enclosing the adsorption separator of the assembly so that a skirt portion of the bell abuts the assembly and the top wall of the bell is penetrated by the central tube, radial apertures in the wall of the central tube connect the tube bore with the bell interior, and a closure nut in screw-threaded engagement with the upper end of the central tube clamps the bell to the assembly.

8. Apparatus according to claim 6 or 7, wherein a gas inlet duct in the floor portion of the vessel communicates with the bore of the supporting ring.

9. Apparatus according to claim 6 or 7 or 8, wherein a liquid outlet duct in the floor portion of the vessel communicates with the vessel space surrounding the supporting ring.

10. Apparatus according to any one of claims 4 to 9, wherein the top portion of the vessel consists of a cover which is removable to permit withdrawal of the separators from the vessel.

11. Apparatus according any one of claims 4 to 10, wherein the U-ducting and the separators are circular, the separators being concentric with the U-ducting.

12. Apparatus according to any one of claims 4 to 11, wherein the agglomerating separator includes a permeable baffle ring enclosing and spaced from the annular layer.

13. Apparatus for separating a gas/liquid mixture, substantially as hereinbefore described with reference to Fig. 1 or Fig. 2 of the accompanying drawings.