WO1999051323A1

WO1999051323A1 - Gas scrubbing and scrubbing liquor recovery apparatus

Info

Publication number: WO1999051323A1
Application number: PCT/ZA1999/000007
Authority: WO
Inventors: Klaus Karl Hans Fertl
Original assignee: Luterek, Janusz, Franciszek
Priority date: 1998-04-02
Filing date: 1999-03-30
Publication date: 1999-10-14
Also published as: AU3389099A

Abstract

A gas scrubbing and scrubbing liquor recovery apparatus (1) for the removal under wet scrubbing conditions of entrained particles and/or other contaminants from a contaminated gas or vapour phase. The apparatus is of the type including a scrubbing liquor sump (2) and a gas or vapour scrubbing zone, wherein during use of the apparatus, the gas or vapour phase is intimately contacted with scrubbing liquor derived from the sump, after which the scrubbing liquor loaded with contaminants from the gas or vapour phase is separated from the gas or vapour phase and returned to the sump for reuse after clarification by separation of a distinct phase of the contaminants therefrom. The apparatus includes an external contaminant separator and concentrator vessel (33), having a first compartment (53), a second compartment (50) and a partition (37) between the first and second compartments. Communication passage means are provided between a region of the first compartment where scrubbing liquor at least partly freed of the distinct phase of contaminant is likely to accumulate during use of the apparatus, on the one hand, and the second compartment on the other hand. Withdrawal means (46, 47, 48) adapted to withdraw contaminant-loaded scrubbing liquor and contaminants from a region of the sump where contaminants tend to accumulate as a phase distinct from the scrubbing liquor phase are also provided. The withdrawal means discharge into the first compartment of the separator and concentrator vessel. The apparatus includes return ducting (51) adapted to return at least partly decontaminated scrubbing liquor from the second compartment to the sump.

Description

Gas Scrubbing and Scrubbing Liquor Recovery Apparatus

The present invention relates to a gas scrubbing and scrubbing liquor recovery apparatus. More particularly, the present invention relates to an apparatus for the removal under wet scrubbing conditions of entrained particles and/or other contaminants from a contaminated gas or vapour phase, e.g. air, of the type including a scrubbing liquor sump and a gas or vapour scrubbing zone, wherein, during use of the apparatus, the gas or vapour phase is intimately contacted with scrubbing liquor derived from the sump, after which the scrubbing liquor loaded with contaminants from the gas or vapour phase is separated from the gas or vapour phase and returned to the sump for reuse after clarification by separation of contaminants therefrom.

Such an apparatus is described in DE-PS 36 10 780, the relevant contents of which are to be considered a part of the present disclosure. That apparatus has been very successful in practice. However, that apparatus did not solve adequately all problems of purifying the scrubbing liquor for recycling and reuse and the concentration, removal from the apparatus and eventual disposal of the contaminants accumulating in the sump. In the aforesaid prior art apparatus it was necessary to disconnect the entire sump from time to time in order to remove and discard the contents of the sump including the contaminants accumulated therein and in order to laboriously dislodge solid matter adhering to the walls and bottom of the sump. This was inconvenient, time consuming and involved relatively frequent and long stand-down periods as well as relatively large losses of scrubbing liquor, because the sludge to be dumped still contained large volumes of liquid.

The applicant has now recognised a need for improvements whereby substantially complete recycling and reuse of scrubbing liquor becomes possible, the only significant losses which have to be replenished being those resulting from evaporation. A need has further been recognised that the contaminant to be disposed of, should be present in highly concentrated form, and solid contaminants should, when dumped or disposed of, have a low liquid content which will evaporate within days. This is particularly important if it is desired to subject such solids to subsequent separation or upgrading processes, in particular, dry separation processes, such as magnetic separations in order to separate the solids into ferromagnetic and non-magnetic fractions.

The present invention provides an apparatus as set out in the introductory paragraph and which further includes an external contaminant separator and concentrator vessel, withdrawal means adapted to withdraw contaminant loaded scrubbing liquor and contaminants from a region of the sump where contaminants tend to accumulate as a phase distinct from the scrubbing liquor phase and further adapted to discharge into a first compartment of the separator and concentrator vessel, a second compartment in the separator and concentrator vessel, a partition between the first and second compartment including communication passage means between a region of the first compartment where scrubbing liquor at least partly freed of the distinct phase of contaminant, is likely to accumulate, on the one hand, and the second compartment on the other hand; and return ducting adapted to return at least partly decontaminated scrubbing liquor from the second compartment to the sump.

Preferably, the external contaminant separator and concentrator vessel is adapted to be disconnected from the apparatus (e.g. disconnected from the sump) and removed for disposal of contaminant accumulated in the vessel. More particularly, such vessel may be designed as a mobile waste tipping container, e.g. adapted to be picked up by a vehicle such as a forklift, a front- end loader, or a special waste container transportation and picking-up vehicle. In accordance with a preferred embodiment, the communication passage means between the compartments is provided by a weir. If the apparatus is intended for use in circumstances where the scrubbing liquor is a phase lighter than the contaminant phase such weir will be an overflow weir, the reverse being true if the contaminant has a density lower than the density of the scrubbing liquor.

Preferably, the apparatus includes a baffle on the upstream side of the weir, separated by a gap from the partition, which gap provides a meandering path from the first compartment through the gap, via the weir and into the second compartment. This arrangement facilitates a clean separation of the clarified scrubbing liquor from the sludge or other contaminants left behind in the first compartment, at the locality from where the clarified scrubbing liquor is to be returned to the sump.

Preferably, the partition is hinged to the inside of the vessel, preferably, in a manner allowing removal of the partition.

In accordance with preferred embodiments the withdrawal means adapted to withdraw contaminant-loaded scrubbing liquor and contaminant includes a sludge pump and is configured for discharging into the first compartment against a discharge baffle. This discharge baffle is designed to minimise agitation of the contents of the first compartment.

The scope of the invention is intended to extend to the external contaminant separator and concentrator vessel as such and to its various features as described above, even when separated from the gas or vapour scrubbing apparatus itself. The invention further extends to the use of such vessel for the separation of distinct phase contaminants from a gas scrubbing liquor in order to recycle the latter in the context of cleaning contaminated air, gases or vapours in a gas scrubbing process. In the majority of cases the apparatus is designed to separate heavier contaminant phase, in particular, solid phase, from a lighter scrubbing liquor phase. In that case, a first accumulation of solid contaminant will already take place in sludge form near the bottom of the sump which, preferably, is funnel- shaped^', and the withdrawal means then has an inlet near the said bottom.

It will be understood that, although the invention had originally been conceived primarily for the purpose of separating solid particles from a scrubbing liquor, used in purifying dust-laden air, gases or vapours - e.g. air withdrawn from sand, grit or shotblasting operations - it can also be used in an analogous manner for separating liquids forming a separate liquid phase in the used scrubbing liquor, e.g. oils or solvents. If these contaminants are lighter than the scrubbing liquor, they will accumulate at the top of the scrubbing liquor, and the apparatus and use thereof have to be adapted accordingly in a manner readily understood by those skilled in the art. The same applies in the case of solid contaminants such as waxes, having a density lower than that of the scrubbing liquor which is usually water or an aqueous solution. In all such cases the inlet of the withdrawal means will have to be situated near the top of the sump, the communication passage means between the two compartments of the external contaminant separator and concentrator vessel will be provided near the bottom of the vessel, and the return of clarified scrubbing liquor will be routed from nearer the bottom of the second compartment to a region of the sump from where clarified scrubbing liquor enters the scrubbing process.

The invention is also applicable to uses where contaminants scrubbed from gases or vapours are themselves gaseous or vaporous and become dissolved in the scrubbing liquor from where they are subsequently removed by chemical precipitation in the form of solid or liquid reaction products. This may be attained by solutes already present in or subsequently added to the scrubbing liquor, e.g. in the sump or in the separator or concentrator vessel. Quite generally, the invention may be used with procedures involving the addition into the sump or separator and concentrator vessel of various additives and auxiliaries, e.g. substances which in a manner known per se promote de-emulsification and/or act as anti-foaming agents and/or as coagulants.

In the following the invention will be further described by way of example with reference to the accompanying drawings wherein

Figure 1 represents an embodiment of a gas scrubbing apparatus according to the invention in a diagrammatic vertical section;

Figure 2 represents a horizontal section through the disentrainment chamber along line ll-ll in Figure 1;

Figure 3 represents a partly sectionalised side elevation of a removable external contaminant separator and concentrator vessel for separating contaminants from the scrubbing liquor and recycling the latter into the system.

Referring now to Figure 1 and 2 of the drawings, the gas scrubber apparatus 1 in its preferred embodiment according to the invention as illustrated is composed of a number of basically cylindrical sections flanged together one on top of the other. The bottom section is the scrubbing liquor sump 2 onto which, by means of flanges 3, the inlet chamber 4 is fitted. The inlet chamber 4 has a gas or vapour feed passage 5 which enters horizontally and eccentrically and substantially in a tangential direction to the cylinder walls of inlet chamber 4.

5 Concentrically about the central axis 7 of the basically cylindrical apparatus 1 a slightly frustro-conical gas or vapour forwarding passage 6, having its wider open bottom end slightly below the feed passage 5, tapers towards the gas or vapour propelling device 8. This takes the form of a centrifugal fan, likewise coaxial about the central axis 7 and opening directly and without any obstructions into the bottom end of the downstream disentrainment chamber 9 fitted by flange connections 12 to the top of the inlet chamber 4. The disentrainment chamber 9 is followed in upward direction by an outlet chamber 10, flange-fitted at 13 to the top of the disentrainment chamber and terminating at its top in a slightly narrower gas outlet vent 11. A horizontal baffle 14 is fitted at the level of the flanges 12, partitioning the disentrainment chamber 9 from the inlet chamber 4. Near the outer walls of the apparatus the baffle includes a series of peripheral drainage apertures 15 which allow for substantially unimpeded drainage of disentrained liquor downward from the bottom of the disentrainment chamber through the inlet chamber 4 back into the sump 2. The fan 8 is driven by a coaxially fitted waterproof drive motor 16 supported on mounting brackets 17 spanning the downstream disentrainment chamber 9.

Just above the mounting brackets 17 the cylindrical wall 19 of the disentrainment chamber bulges outwardly to form a liquor catching formation 18 which, viewed in the direction of spin 22 of the gas or vapour inside the disentrainment chamber and imparted by the spin 23 of the fan 8 flares radially outwardly until it terminates in an end wall 20 serving as a particle catching wall leading radially back towards the cylindrical peripheral wall 19. Near that end wall 20 the catching formation has a drainage hole and passage 21 , leading downward into the inlet chamber 4 and serving to return scrubbing liquor and contaminants disentrained in the liquor catching formation downwards back towards the sump 2. It is important to note that in contrast to the prior art apparatus according to DE-PS-36 10 780 the centrifugally acting fan 8 is mounted completely freely exposed in the bottom end of the disentrainment chamber 9, a feature which has been found to contribute greatly to the efficiency of the apparatus.

Further, in accordance with the invention, a baffle 24 mounted on a central pillar 26, adjustably fitted in a support sleeve 28 held by the support bracket 27 is held at a predetermined level above the scrubbing liquor level 25 in the sump 2. This baffle 24 serves to regulate the effect of the cyclonic inrush of air through the feed passage 5 and is designed to allow adequate entrainment of scrubbing liquor in the forwarded gas phase whilst mitigating excessive wave action in the sump. The level of baffle 24 is normally adjusted on the basis of experience at the time when the apparatus is set up for a particular industrial application and usually does not require further adjustment once the apparatus is taken into operation.

The sump 2 is frustro-conically shaped at its bottom to promote a concentration of the contaminant sludge collecting at the bottom of the sump. On one side the sump comprises an open ended funnel-like inlet formation 30 through which the scrubbing liquor level can be observed and replenished when the need arises to make up mainly for evaporation losses.

As in the case of the prior art apparatus according to DE-PS-36 10 780 a perforated screen 31 is provided against the. cylindrical wall of the inlet chamber 4, approximately opposite to the inlet end of the feed passage 5.

In order to further promote the cyclonic movement of the gas or vapour flow in the inlet chamber, the inside of the cylindrical wall of the inlet chamber comprises worm-like spin inducing invertly directed ridges.

7- The gas or vapour scrubbing apparatus described so far with reference to Figs. 1 and 2 operates as follows:

The fan 8 spinning at high speed induces a suction effect by means of which the gas or vapour, e.g. dust laden air, is drawn in the direction of the arrow 60 with a spin into the inlet chamber 4 where, partly guided by the baffle 24, as shown by arrows 61 and 62, the gas sweeps over parts of the scrubbing liquor surface 25 in the sump and picks up a percentage of scrubbing liquor in droplet form before rising through the gas or vapour forwarding passage 6 in the direction of arrow 63 into and through the fan 8.

Inside the inlet chamber the gas already experiences a substantial degree of spin and cyclonic action causing mainly the larger dust particles to be urged against the cylindrical wall of the chamber and becoming disentrained and to drop down into the sump 2.

The fan 8 expels the air and gas laden with dust and entrained scrubbing liquor in the direction of arrow 64 at high speed and the gas continues to spin as indicated by arrow 22 in the disentrainment chamber 9 as the gas progressively rises towards the outlet vent 11 as indicated by arrows 65 and 66. As the gas and vapour phase rises, the entrained droplets and solid particles are progressively urged by centrifugal forces towards the cylindrical wall 19 and eventually into the outwardly bulging liquor catching formation 18. At that stage the liquor droplets have become thoroughly contacted with the contaminants in the gas or vapour phase, i.e. solid particles in the event of dust, or even vaporous or gaseous contaminants. These droplets settle out against the wall of 18 and the end wall 20 and drain downwards towards the liquor collecting and return passage 21 and from there back into the inlet chamber and down into the sump 2. Liquor settling out against the wall 19 likewise drains in downward direction under the action of gravity and passes through the apertures 15 of the baffle 14 to return to the sump 2. The nature and composition of the scrubbing liquor will depend on the nature of the gases and vapours to be scrubbed and the contaminants to be removed therefrom. In many cases, particularly in the case of dust laden air withdrawn from sand or grit blasting chambers, the scrubbing liquor will be an aqueous liquor, more particularly water with or without additives. Additives may include wetting agents. They may also include anti-foaming agents to avoid excessive foaming in the sump. Additives may also be added which promote the segregation and aggregation of contaminants (whether liquid or solid) from the aqueous liquor in the sump.

In accordance with preferred embodiments a separation of aqueous scrubbing liquor and contaminants accumulating in the sump is to be brought about in order to permit the scrubbing liquor to be used over and over again in the scrubbing process performed in the scrubbing apparatus. In accordance with the prior art apparatus described in DE-PS 36 10 780 such separation was confined to the sump itself where the higher density solids progressively settled and accumulated at the bottom of the sump which from time to time was removed from the bottom of the apparatus for removing and discarding the accumulated deposits and for cleaning.

In accordance with the embodiment illustrated in the drawings, the separation of scrubbing liquor from contaminants has been transferred to an external contaminant separator vessel 33, which in this case takes the form of a free standing tippable waste container having a base 34 supporting a waste bucket hinged to the base via a hinge axis 35, its front wall taking the form of an oblique discharge wall over which, when the bucket is tipped around the hinge axis 35, the contents are discharged. Close to the rear wall 39 an internal partition 37 is provided, hinged to the inside of the side walls of the bucket at hinge point 38. The partition divides the bucket into a sludge settling chamber 53 and a clear liquor chamber 50.

9 At the designed liquid level 54 inside the bucket, the partition 37 comprises an overflow weir 40 shielded from the chamber 53 by a preceding baffle 42, the bottom edge of which forms an underflow weir 41. Rearward angular movement of the partition beyond the vertical position is prevented by one or more stop formations 45. Angular forward movement is possible as indicated by the arrow 44. A meandering path 43 is defined by the gap between the baffles 42 and 37 and the underflow and overflow weirs 41 , 40.

To the outside of the apparatus 1 a sludge pump 46 is mounted which through an intake pipe 47 withdraws sludge from near the bottom region 29 of the sump 2 and discharges it through a discharge pipe 48 onto a discharge baffle 49, mounted just above the liquor level 54 inside the sludge settling chamber 53 of the bucket. Sludge settles out in that chamber to an ever increasing level 52 whereas the supernatant clarified liquor proceeds (path 43) into the clear liquor chamber 50. From there the clear liquor is picked up by a return pipe 51 and returned into the sump 2.

Some further details of the contaminant separator vessel are apparent from fig. 3 where it is shown that the partition 37 is hung inside an upwardly open- ended hinge pin support 100. It is also shown there that the tipping bucket is hinged to the support base 34 via a hinge bracket 101 coacting with the hinge pin 35. The support base 34 is rearwardly extended by an extension 108 to which, at hinge point 109, an upright locking lever 102 is hinged which carries a catch 104 coacting with a locking pin 103 mounted to the bottom end of the rear wall 39 of the bucket. Near the top of rear wall 39 an eye 110 is provided to which a locking loop 105 for the top of the lever 102 is articulated.

In normal operation and in the position shown in Fig. 3, the bucket of the contaminant separator vessel 33 is secured against tipping. Once the sludge level 52 has risen so much that adequate clarification of scrubbing liquor is impeded, the sludge pump 46 is stopped and the feed pipe 48 and return pipe 51 are disconnected to permit removal of the separator vessel 33. This

10 is done, for example, by a forklift which engages underneath support 34 to pick up the vessel and carry it to a dumping and discharge place. There the loop 105 is raised and disengaged from the lever 102 which is pulled back in the direction 106 for the catch 104 to be released from the locking pin 103. The bucket is then tipped in the direction 107 about the hinge axis 35 in order to discharge the contents of the bucket, in the course of which the partition 37 swings forward in the direction 44. In order to facilitate cleaning of the bucket, the partition 37 may be lifted off the hinge pin support 100.

While the separator vessel is removed and emptied, a second similar vessel may be set up next to the scrubbing apparatus, so that sludge separation may continue almost without interruption. Alternatively, sludge separation is temporarily interrupted until the original separator vessel is returned to its previous position.

With the arrangement just described it was found that the scrubbing liquor near the top of the sump 2 is relatively clear so that effective gas and vapour scrubbing may proceed in the apparatus. Due to this feature as well as the remaining features of the scrubbing apparatus a high degree of decontamination of the gas or vapour stream was found to be achievable. Due to the effectiveness of the separation taking place in the contaminant separator vessel it was possible to minimise losses of scrubbing liquor with the discarded sludge so that not much more liquor is lost than is due to evaporation in the scrubbing apparatus.

Due to the relatively low scrubbing liquor content of the sludge at the stage of it being tipped out and dumped, it was found that the sludge can be dried very rapidly. This is of importance if the sludge is to be subjected to further treatment under dry conditions, e.g. by magnetic separation in order to recover or separate magnetic components or any other forms of dry solid separation treatments.

11 For purposes of describing a preferred embodiment of the invention, the scrubbing apparatus 1 has been described in combination with the main aspect of the present invention, namely the contaminant separator vessel 33 and the various described means forming part thereof or being ancillary thereto. It should be understood, however, that the contaminant separator vessel according to the invention could also be used successfully with different designs of gas or vapour scrubbing apparatus or in other situations where contaminated liquors arise which have to be separated into clarified liquor and the contaminants. It will be understood that the invention may also be applied in combination with the scrubbing apparatus substantially as described in prior art DE-PS-36 10 780.

It should be further understood that the reference to contaminants should not be interpreted restrictively. The substances separated from the liquor may well be valuable substances or contain valuable substances in their own right.

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Claims

1. A gas scrubbing and scrubbing liquor recovery apparatus (1 ) for the removal under wet scrubbing conditions of entrained particles and/or other contaminants from a contaminated gas or vapour phase, of the type including a scrubbing liquor sump (2) and a gas or vapour scrubbing zone, wherein during use of the apparatus, the gas or vapour phase is intimately contacted with scrubbing liquor derived from the sump, after which the scrubbing liquor loaded with contaminants from the gas or vapour phase is separated from the gas or vapour phase and returned to the sump for reuse after clarification by separation of a distinct phase of the contaminants therefrom, characterised by further including an external contaminant separator and concentrator vessel (33), having a first compartment (53), a second compartment (50) and a partition (37) between the first and second compartments having communication passage means between a region of the first compartment where scrubbing liquor at least partly freed of the distinct phase of contaminant is likely to accumulate during use of the apparatus, on the one hand, and the second compartment on the other hand; withdrawal means (46, 47, 48) adapted to withdraw contaminant-loaded scrubbing liquor and contaminants from a region of the sump where contaminants tend to accumulate as a phase distinct from the scrubbing liquor phase and further adapted to discharge into the first compartment of the separator and concentrator vessel; and return ducting (51 ) adapted to return at least partly decontaminated scrubbing liquor from the second compartment to the sump.

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2. An apparatus (1 ) as claimed in Claim 1 , characterised in that the external contaminant separator and concentrator vessel (33) is adapted to be disconnected from the apparatus (1 ) and removed for disposal of contaminant accumulated in the vessel.

3. An apparatus (1 ) as claimed in Claim 1 or Claim 2, characterised in that the external contaminant separator and concentrator vessel (33) is designed as a mobile waste tipping container, adapted to be picked up by a vehicle.

4. An apparatus (1 ) as claimed in any one of Claims 1 to 3 inclusive, characterised in that the communication passage means between the compartments (50, 53) of the external contaminant separator and concentrator vessel (33) is provided by a weir (40).

5. An apparatus (1 ) as claimed in Claim 4, characterised by a baffle (42) on the upstream side of the weir (40), separated by a gap from the partition (37), the gap providing a meandering path (43) from the first compartment (53) through the gap, via the weir, and into the second compartment (50).

6. An apparatus (1 ) as claimed in any one of Claims 1 to 5 inclusive, characterised in that the partition (37) is removably hinged to the inside of the separator and concentrator vessel (33).

7. An apparatus (1 ) as claimed in any one of Claims 1 to 6 inclusive, characterised in that the withdrawal means (46, 47, 48) adapted to withdraw contaminant-loaded scrubbing liquor and contaminant includes a sludge pump (46) and is configured for discharging into the first compartment (53) against a discharge baffle (49).

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8. An apparatus (1 ) as claimed in any one of Claims 1 to 7 inclusive, characterised in that it is designed to separate a heavier contaminant phase from a lighter scrubbing liquor phase, the sump (2) being funnel-shaped and the withdrawal means (46, 47, 48) having an inlet (47) near the bottom of the sump.

9. An apparatus (1 ) as claimed in any one of Claims 1 to 7 inclusive, characterised in that it is designed to separate a lighter contaminant phase from a heavier scrubbing liquor phase, the withdrawal means (46, 47, 48) having an inlet near the top of the sump (2), the communication passage means between the two compartments (50, 53) of the separator and concentrator vessel (33) being provided near the bottom of the vessel, and the return ducting being configured for ducting the partly decontaminated scrubbing liquor from near the bottom of the second compartment (50) to the sump.

10. An apparatus (1 ) as claimed in any one of Claims 1 to 9 inclusive, characterised by dosing means provided in the sump (2) or in the separator or concentrator vessel (33), for introducing solutes, additives and/or auxiliaries to the scrubbing liquor.

11. An external contaminant separator and concentrator vessel (33) for use in conjunction with a gas scrubbing and scrubbing liquor recovery apparatus (1 ) for the removal under wet scrubbing conditions of entrained particles and/or other contaminants from a contaminated gas or vapour phase, of the type including a scrubbing liquor sump (2) and a gas or vapour scrubbing zone, wherein during use of the apparatus, the gas or vapour phase is intimately contacted with scrubbing liquor derived from the sump, after which the scrubbing liquor loaded with contaminants from the gas or vapour phase is separated from the gas or vapour phase and returned to the sump for reuse after clarification by separation of a distinct phase of the contaminants therefrom,

15, characterised by a first compartment (53), a second compartment (50) and a partition (37) between the first and second compartments, having communication passage means between a region of the first compartment where in use scrubbing liquor at least partly freed of the distinct phase of contaminant is likely to accumulate, on the one hand, and the second compartment on the other hand.

12. A vessel (33) as claimed in Claim 11 , characterised by being adapted to be disconnected from the apparatus (1 ) and removed for disposal of contaminant accumulated in the vessel.

13. A vessel (33) as claimed in Claim 11 or Claim 12, characterised by being designed as a mobile waste tipping container, adapted to be picked up by a vehicle.

14. A vessel (33) as claimed in any one of Claims 11 to 13 inclusive, characterised in that the communication passage means between the compartments (50, 53) of the external contaminant separator and concentrator vessel (33) is provided by a weir (40).

15. A vessel (33) as claimed in Claim 14, characterised by a baffle (42) on the upstream side of the weir (40), separated by a gap from the partition (37), the gap providing a meandering path (43) from the first compartment (53) through the gap, via the weir, and into the second compartment (50).

16. A vessel (33) as claimed in any one of Claims 1 to 15 inclusive, characterised in that the partition (37) is removably hinged to the inside of the separator and concentrator vessel (33).

16,

17. The use of an apparatus (1 ) as claimed in any one of Claims 1 to 10 inclusive, or of a vessel as claimed in any one of claims 11 to 16 inclusive, for the separation of distinct phase contaminants from a gas scrubbing liquor, in order to recycle the latter in the context of cleaning contaminated air, gases or vapours in a gas scrubbing process.

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