GB2395904A

GB2395904A - Apparatus for volatilising a decontamination agent

Info

Publication number: GB2395904A
Application number: GB0327852A
Authority: GB
Inventors: Kuno Lemke; Helmut Weber; Thomas Hertfelder
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2002-12-03
Filing date: 2003-12-01
Publication date: 2004-06-09
Anticipated expiration: 2023-12-01
Also published as: GB2395904B; GB0327852D0; CH696801A5

Abstract

An apparatus for volatilising a decontamination agent comprising a compressed air source 12 and a compressed air line leading to at least one decontamination agent vaporiser 74. The compressed air line opens up into a venturi nozzle 14 to which is connected the decontamination agent line which is connected to a decontamination agent storage vessel 20. A filter 16 may be arranged in the compressed air line upstream from the venturi nozzle. An auxiliary venturi nozzle (31, Fig. 2) may be connected upstream of the filter into which nozzle opens a branch (32, Fig. 2) of the decontamination line. A filter (41, Fig. 3) may be arranged between the venturi and the vaporiser. The decontamination storage vessel may be equipped with a quantity analysis device 21, such as a load cell, which cooperates with a metering device 22. A lifting cylinder 23 may be provided for immersing a line in the decontamination storage vessel and removing it therefrom. The venturi nozzle may have a textured surface and may comprise a diffuser nozzle which is at least in part controllable via a temperature sensor (78, Fig. 6). The decontamination agent may be hydrogen peroxide.

Description

Apparatus for volatilizing a decontamination agent Prior art

The invention starts from an apparatus for volatilizing a decontamination agent according to the type defined in greater detail in the precharacterising clause of claim 1.

10 Such an apparatus is known from practical application and may be used, for example, for disinfecting or biodecontaminating an isolator which serves in the pharmaceutical industry as a hermetically sealed system for aseptic packaging of pharmaceutical products.

Such a known apparatus for volatilizing hydrogen peroxide serving as decontamination agent comprises a compressed air source, which leads via a compressed air line to a hydrogen peroxide vaporiser, together with a hydrogen peroxide 20 storage vessel which is connected with the hydrogen peroxide vaporiser via a hydrogen peroxide line equipped with a pump. The apparatus operates in such a manner that the hydrogen peroxide is pumped via a nozzle into the vaporiser, where it vaporises and is then discharged by 25 means of the compressed air into a space which is to be decontaminated or sterilized.

CH 689 178 AS furthermore discloses an apparatus for the gaseous decontamination of clean rooms. In said apparatus, 30 hydrogen peroxide is delivered by means of a pump from a storage vessel to a vaporiser arranged in a clean room, such as the internal chamber of an isolator. The hydrogen peroxide is vaporised in the vaporiser.

- 2 An installation is furthermore known from practical application in which the hydrogen peroxide is trickled by means of a pump onto a hot plate arranged in a machine room 5 to be decontaminated, then vaporized in the open in the machine room and distributed by means of air from a blower.

In foodstuffs technology, hydrogen peroxide (H2O2) is used as a liquid starting product for decontamination. At 10 elevated concentrations, i.e. in concentrations of greater than 3 vol.%, hydrogen peroxide has corrosive properties.

Even at low concentrations, for example at a concentration of between 1500 ppm and 2500 ppm, hydrogen peroxide in vapour form is capable of killing not only bacteria and the 15 spores thereof but also fungi, yeasts and viruses. To this end, the liquid starting product is vaporised in a suitable hydrogen peroxide volatilizer.

Advantages of the invention The apparatus according to the invention for volatilising a decontamination agent having the features according to the precharacterising clause of claim 1, in which apparatus the pressure line opens into at least one venturi nozzle, which 25 is connected with the decontamination agent line, has the advantage that the compressed air serving as the carrier gas for the decontamination agent can simultaneously be used to convey the decontamination agent from the decontamination agent storage vessel into the 30 decontamination agent vaporiser. The venturi nozzle aspirates the decontamination agent and sprays it into the decontamination agent vaporiser by means of the compressed air.

The venturi nozzle is thus configured such that it operates in accordance with the principle of a water-jet pump, the compressed air being used to pump a liquid phase. It is 5 possible to dispense with a costly pump with an additional nozzle for delivering the decontamination agent into the decontamination agent vaporiser.

The venturi nozzle furthermore has the advantage that it 10 comprises no moving parts and is thus substantially wear-

free. The term "decontamination" used here should be understood in its widest meaning and also encompasses not only the 15 terms "sterilization" and "disinfection", but also the term "biodecontamination" used in pharmaceutical engineering.

In a convenient embodiment of the apparatus according to the invention, inflow of compressed air and/or inflow of 20 decontamination agent may in each case be controlled by means of a control valve, which may take the form of a metering valve.

In order to ensure that the compressed air introduced into 25 venturi nozzle is sterile and that the venturi nozzle is not clogged by any entrained dust, a filter may be provided in the compressed air line upstream from the venturi nozzle. This filter is conveniently a conventional commercial sterile filter, for example taking the form of a 30 membrane filter.

An auxiliary venturi nozzle, into which a branch from the decontamination agent line opens, may furthermore be

- 4 provided upstream from the filter. In this way, the filter can be exposed to a mixture of air and decontamination agent droplets and so itself be subjected to presterilisation. A further control valve is conveniently arranged in the branch of the decontamination agent line which opens into the auxiliary venturi nozzle. Once the filter has been presterilised, said control valve is closed at a convenient 10 stage in the operating sequence and a further control valve, which is arranged in a bypass which bridges the auxiliary venturi nozzle, is opened. In this manner, the filter arranged downstream from the auxiliary venturi nozzle is blown clear of decontamination agent. The desired 15 mixture of air and decontamination agent droplets may then be produced in the venturi nozzle or main venturi nozzle, delivered to the vaporiser and vaporised therein. In this embodiment, the filter is only transiently exposed to the decontamination agent. Because the filter has been blown 20 clear after being presterilised, the pores of the filter are open during the actual volatilization of the decontamination agent by means of the venturi nozzle and vaporiser. There is thus no consequential increase in flow resistance. Alternatively or also additionally, a further filter, in particular taking the form of a sterile filter, may be arranged between the venturi nozzle and the decontamination agent vaporiser. As a result, the filter is inevitably also 30 sterilized during operation of the apparatus, i.e. during injection of the decontamination agent into the vaporiser.

The decontamination agent vaporiser is conveniently an electrically heated vaporiser. Such a vaporiser may be designed in such a manner that the problems with leaks which would be encountered with a steam-operated vaporiser 5 do not occur. The vaporiser may be heated, for example, by means of heating cartridges, which are embedded in an aluminium casting, or by microwaves or by thermal radiation. However, in-the latter case, the vaporiser tube to be used must allow the radiation to pass through.

It is also conceivable to use an additional, suitably constructed vaporiser module to preheat the compressed air upstream from the venturi nozzle.

15 The decontamination agent vaporiser may furthermore be constructed from at least two individual vaporisers which are connected in series. The first individual vaporiser which the air/decontamination agent mixture passes through may be operated at a comparatively high temperature, such 20 that the decontamination agent is rapidly vaporised. The second individual vaporiser arranged downstream from the first individual vaporiser serves to adjust the mixture to be discharged from the apparatus to the desired temperature. In an advantageous embodiment of the apparatus according to the invention, the decontamination agent storage vessel is a dispensing bottle. Such a dispensing bottle may be dimensioned such that it contains the quantity of 30 decontamination agent which is required to decontaminate a space, for example an internal chamber of an isolator used in the pharmaceutical industry. This has the advantage that a fresh dispensing bottle may be used for each

- 6 decontamination operation, so minimising the risk of decomposition of the decontamination agent, for example hydrogen peroxide, contained in the dispensing bottle. If the dispensing bottle is designed such that the 5 decontamination agent is sufficient to decontaminate a space twice or more, it is convenient to check the concentration of the decontamination agent in the bottle before each individual decontamination operation.

10 The decontamination carried out by means of the apparatus according to the invention may be controlled by providing the decontamination agent storage vessel with a quantity analysis device. The contents of the vessel may be monitored by means of this device and the control valves of 15 the apparatus appropriately controlled. In particular, withdrawal of decontamination agent from the storage vessel may be monitored in this manner and stopped once the required quantity necessary for decontamination has been consumed. The stream of decontamination agent which is 20 apportioned into the compressed air may also be adjusted by appropriate control of the control valve, which may take the form of a metering valve, assigned to the decontamination agent line.

25 In particular when the storage vessel takes the form of a dispensing bottle, a load cell is a convenient quantity analysis device.

Instead of cooperating with the control valve arranged in 30 the decontamination agent line, the quantity analysis device may also cooperate with an alternative metering device which is arranged in the decontamination agent line.

The metering device may be either a further metering valve

- 7 or also a tube pinching device for a decontamination agent line taking the form of a flexible tube. In this way, the flow rate of decontamination agent may be modified reproducibly by pinching the suction tube. This may, 5 however, also be performed by means of the additional metering valve or the control valve designed as a metering valve. In order to ensure that the decontamination agent line is 10 emptied after completion of a decontamination performed by means of an apparatus according to the invention and that there is thus no uncertainty with regard to the concentration of the decontamination agent remaining in the line due to the decomposition of said agent, the apparatus 15 according to the invention advantageously comprises a moving component for immersing the line in the decontamination agent storage vessel. The moving component, which may be a lifting cylinder, immerses the line in the decontamination agent at the beginning of a decontamination 20 operation and lifts it back out thereof on completion of the decontamination operation.

It is also conceivable to provide a dispensing bottle which contains decontamination agent for two or more 25 decontamination operations. In this case, the load cell deducts the intended quantity from the stock until the decontamination agent contained in the dispensing bottle is no longer sufficient for another decontamination. The load cell conveniently then transmits an alarm signal to a 30 monitoring or control means of the apparatus according to the invention. At the end of each decontamination operation, the decontamination agent line is sucked empty, the decontamination agent line being drawn out of the

- 8 decontamination agent. The control valve connected with the decontamination agent line, which in particular takes the form of a suction tube, is then closed. This has the advantage that only fresh decontamination agent is 5 aspirated from the dispensing bottle on a subsequent decontamination operation.

In order to achieve uniformly fine atomization or volatilization of the decontamination agent without the 10 formation of large drops, the venturi nozzle may comprise a diffuser or outlet nozzle which has a textured surface. In this manner, turbulence can be imparted to the decontamination agent/air mixture.

15 The diffuser or outlet nozzle of the venturi nozzle may furthermore be at least in part temperature-controllable, which in turn promotes uniformly fine atomization or volatilization of the decontamination agent.

20 In one specific embodiment of the apparatus according to the invention, two or more venturi nozzles may also be connected in parallel. These may be supplied by one or also two or more decontamination agent lines.

25 Decontamination agent may also be sprayed into the vaporiser at regular intervals, for example spraying is performed for five seconds and then ten seconds are allowed to elapse before the next spraying operation. The pressure of the compressed air delivered to the venturi nozzle may 30 furthermore be varied.

- 9 Further advantages and advantageous developments of the subject matter of the invention may be found in the description, the drawings and the claims.

5 Drawings Six exemplary embodiments of an apparatus according to the invention are shown in the drawings in simplified schematic form and are explained in greater detail in the following 10 description. The Figures show

Figure 1 a first embodiment of an apparatus according to the invention; Figure 2 a second embodiment of an apparatus according to the invention; 15 Figure 3 a third embodiment of an apparatus according to the invention; Figure 4 a decontamination agent vaporiser of the apparatuses according to Figures 1 to 3; Figure 5 a fourth embodiment of an apparatus according to 20 the invention; Figure 6 a fifth embodiment of an apparatus according to the invention; Figure 7 a sixth embodiment of an apparatus according to the invention; and 25 Figure 8 a decontamination agent vaporiser of the apparatuses according to Figures 5 to 7.

Description of the exemplary embodiments

30 Figure 1 shows an apparatus 10 for volatilizing a decontamination agent which serves to biodecontaminate an isolator 11, illustrated schematically, used in the pharmaceuticals industry.

- 10 The apparatus 10 comprises a first compressed air source 12, which is connected with a first compressed air line 13 which leads to a venturi nozzle 14. The compressed air 5 flowing into the compressed air line 13 is prefiltered, condensate-free and optionally dried.

A control valve 15, which optionally takes the form of a metering valve, and a sterile filter 16 are furthermore 10 arranged in the first compressed air line 13. Downstream from the venturi nozzle 14, there is arranged a vaporiser 17 for hydrogen peroxide, which is connected on the downstream side with a second compressed air line 18 which leads to the isolator 11. Dried air, which serves as the 15 carrier medium, flows in the second compressed air line 18, which is pressurized by a second compressed air source 27.

A line 19 for delivering decontamination agent, in the present case hydrogen peroxide, opens into the venturi 20 nozzle 14. The line 19 at least in part takes the form of a flexible suction tube which, in the operating position, is immersed in a dispensing bottle 20 which contains the hydrogen peroxide.

25 The dispensing bottle 20 is arranged on a load cell 21, which serves to determine the contents of the dispensing bottle 20 and cooperates with a control valve 22, which is arranged between the venturi nozzle 14 and the tube 19.

30 The apparatus 10 comprises a lifting cylinder 23 for immersing the flexible tube 19 in the dispensing bottle 20 and withdrawing it therefrom.

The dispensing bottle 20 is arranged together with the load cell 21 and the lifting cylinder 23 in a separate structural unit 24 of the apparatus 10, the dispensing bottle 20 being accessible via a closable door which is not 5 shown in further detail here.

For safety reasons, the venturi nozzle 14, the hydrogen peroxide vaporiser 17, the sterile filter 16 and the control valves 15 and 22 are arranged in another separate 10 structural unit 25 of the apparatus 10. The two structural units 24 and 25 are connected by the flexible tube 19. It is, however, also conceivable for the structural units 24 and 25 to be incorporated into a common structural unit.

15 The apparatus 10 shown in Figure 1 operates in the manner described below.

In the resting state, the lifting cylinder 23, to which the flexible tube 19 is attached, is extended. This position is 20 shown by the upper end of an arrow adjacent to the cylinder 23 in Figure 1 and may also be designated Pos. 0.

Compressed air is applied via the compressed air line 13 to the control valve 15, which is closed. The suction tube 19 is empty. The load cell 21 is unoccupied.

In order to biodecontaminate the isolator 11, the apparatus 10 is activated, which in particular involves opening the control valve 15, such that compressed air flows to the vaporiser 17, and heating the vaporiser 17 to preheat the 30 compressed air and thus the isolator 11. The dispensing bottle 20, filled with hydrogen peroxide and opened, is then placed on the load cell 21. The load cell 21 recognizes the dispensing bottle 20. The system control

then runs a checking routine to check whether the quantity of decontamination agent present in the dispensing bottle 20 is sufficient to decontaminate the isolator 11. If such is the case, the door of the structural unit 24 is closed, 5 wherein a door contact causes a query to be displayed as to whether the bottle is open. If this is the case, the user acknowledges the query to continue the remainder of the routine. Alternatively, a sensor not shown in greater detail here, may carry out an automatic lid query.

When the hydrogen peroxide vaporiser 17 has reached its required temperature, the short lifting cylinder 23 moves into a position corresponding to the lower end of the arrow adjacent the cylinder 23 in the drawing which position may 15 be designated Pos. 1, such that the flexible tube 19 is immersed in the hydrogen peroxide contained in the dispensing bottle 20. The control valve 22 is then opened, as a result of which hydrogen peroxide is aspirated by means of the venturi nozzle 14 and sprayed into the 20 hydrogen peroxide vaporiser. As soon as a predetermined weight reduction is determined by the load cell 21, the load cell switches the control valve 22 in such a manner that the hydrogen peroxide concentration in the venturi nozzle 14 is altered.

It may alternatively be necessary to provide two or more metering positions. This may, for example, be achieved by a tube pinching device which may be actuated in a continuously variable manner by means of a linear cylinder.

30 Two or more short lifting cylinders may, however, also be used for this purpose.

As soon as the quantity of hydrogen peroxide necessary to decontaminate the isolator 11 has been withdrawn from the dispensing bottle 20, the load cell transmits a signal which effects closure of the control valve 15 located in 5 the compressed air line 13. The lifting cylinder 23 then lifts the flexible tube 19 out of the dispensing bottle 20, specifically by adopting position Pos. 0. The door contact of the door in structural unit 24 is released.

10 The entire tube 19 then empties itself into the dispensing bottle 20, wherein the control valve 22 is open. The dispensing bottle 20 with any residual content may then be removed. 15 In an alternative embodiment, the compressed air flows through the control valve 15 and thus through the venturi nozzle 14 until the flexible tube 19, which has been withdrawn from the dispensing bottle 20, is sucked empty, which may take around 60 seconds. In this manner, it is 20 ensured that no hydrogen peroxide remains in the apparatus 10 until the next biodecontamination.

The quantity of hydrogen peroxide delivered by means of the apparatus according to the invention is, for example, 25 between 4 g/min and 30 g/min.

The quantity of air used for this purpose is, for example, between 4 m3/h and 10 m3/h. The temperature at the outlet of the hydrogen peroxide vaporiser 17 is, for example, 30 between 100 C and 140 C.

The hydrogen peroxide in the dispensing bottle 20 has a concentration of approx. 35 vol.-OO to 50 vol.%.

Figure 2 shows a second embodiment of an apparatus 30 for volatilizing a decontamination agent in the form of hydrogen peroxide. The structural unit comprising the 5 dispensing bottle is not shown, as it corresponds to that of the apparatus according to Figure 1. The apparatus 30 differs from the apparatus according to Figure 1 in that an auxiliary venturi nozzle 31 is connected upstream from the sterile filter 16, said nozzle being arranged downstream 10 from the control valve 15. The auxiliary venturi nozzle 31 substantially corresponds to the venturi nozzle 14 and is connected with a branch 32 of the hydrogen peroxide line 19, such that hydrogen peroxide can be aspirated by means of the venturi nozzle 31 and the compressed air passing 15 therethrough. A further control valve 33 is arranged in the branch 32, by means of which it is possible to control the feed of hydrogen peroxide into the auxiliary venturi nozzle 31. 20 A bypass 34 is furthermore arranged in the area of the auxiliary venturi nozzle 31, said bypass bridging the auxiliary venturi nozzle 31 and comprising a fourth control valve 35. Such an arrangement makes it possible to ensure that the sterile filter 16 is itself sterilised before the 25 hydrogen peroxide is volatilized.

Figure 3 shows a further embodiment of an apparatus 40 for volatilizing hydrogen peroxide. The apparatus 40 differs from that according to Figure 1 in that it comprises a 30 sterile filter 4 which is arranged between the venturi nozzle 14 and the hydrogen peroxide vaporizer 17. No filter is provided between the control valve 15 and the venturi

1 C 1b nozzle 14. The apparatus 40 otherwise corresponds to the apparatus according to Figure 1.

Figure 4 is a detailed representation of the vaporiser 17 5 according to Figures 1 to 3. The vaporizer 17 comprises a corrugated tube 51, through which flows the mixture of hydrogen peroxide droplets and air produced by means of the venturi nozzle 14. The corrugated tube 51 is surrounded by a cast aluminium component 52 in which is embedded a 10 heating element 53, which coils in a spiral around the corrugated tube 51. The cast aluminium component 52 is in turn enclosed in thermal insulation 54, which is delimited by a housing 55. The thermal insulation 54 may be provided by air, a vacuum or by some other insulating material.

15 Adjacent to the housing 55, there is an electrical terminal box 56, which comprises terminals 57 and 58 for the heating element 53 and a terminal 59 for a thermocouple 60, which is embedded in the cast aluminium component 52.

20 Figure 5 shows a further embodiment of an apparatus 70 for volatilizing a decontamination agent in the form of hydrogen peroxide. The apparatus 70 substantially corresponds to -that according to Figure 1, but differs therefrom in that the sterile filter or particle filter 16 25 and the control valve 15 connected upstream therefrom are arranged outside the structural unit 25. The sterile filter 16 is connected via a further compressed air line 72 with the venturi nozzle 14 acting as suction/spray nozzle.

30 The apparatus 70 furthermore comprises an alternative hydrogen peroxide volatilizer or vaporiser 74, which is described in detail below with reference to Figure 8 and inter alla comprises a first temperature sensor 76 which

serves as a monitoring means to protect the vaporiser 74 from overheating. Downstream from the vaporiser 74, there is a second temperature sensor 78 which determines the actual temperature of the mixture and compressed air 5 downstream from the vaporiser 74 and by means of which it is possible to control the required temperature in the vaporiser 74.

The apparatus 70 shown in Figure 5 operates, for example, 10 in the manner described below.

In the resting state of the apparatus 70, the suction tube 19 is empty and thus contains no hydrogen peroxide. The lifting cylinder is in the extended state, i.e. in the 15 position corresponding to the upper end of an arrow adjacent cylinder 23 in Figure 5 and which may be designated Pos. 0. The load cell 21 is empty, i.e. there is no dispensing bottle arranged thereon. The control valves 15 and 22, which may for example be of a spring-closing 20 design, are each closed.

In order to prepare for presterilisation or biodecontamination of the isolator 11, compressed air is applied to the control valve 15 via the compressed air line 25 13. The compressed air is applied, for example, at a pressure of 2 to 5 bar in a prefiltered and condensate-free state to the control valve 15. A full dispensing bottle 20 with fresh hydrogen peroxide is arranged on the load cell 21 and the tube 19 is introduced into the dispensing bottle 30 20. The door of the structural unit 24 is then closed and the lifting cylinder 23 moved into a position corresponding to the lower end of the arrow adjacent the cylinder 23, which position may be designated Pos. 1, such that the

suction tube 19 is immersed in the hydrogen peroxide contained in the dispensing bottle 20.

In order to start biodecontamination, the control valve 15 5 is opened such that the compressed air flows via the compressed air line 72 in the direction of the venturi nozzle 14 and the vaporiser 74. The vaporiser 74 is then heated, such that the compressed air flowing through the vaporiser 74 is heated. Heating of the compressed air is 10 monitored by means of the temperature sensor 78 arranged downstream from the vaporiser 74 and is continued until the desired required temperature is achieved. Heating of the compressed air also preheats the isolator 11.

15 The control valve 22 is then opened, which, due to the "venturi effect", means that hydrogen peroxide is continuously aspirated by means of the venturi nozzle 14 and sprayed into the vaporiser 74.

20 The hydrogen peroxide spray mist produced by means of the venturi nozzle 14 is vaporised in the vaporiser 74. The vaporised hydrogen peroxide then flows together with the compressed air into the dry air flowing through the compressed air line 18 and flows therewith to the isolator 25 11.

Once the required quantity of hydrogen peroxide has been consumed, as determined by the load cell 21, the lifting cylinder 23 is moved into the position designated Pos. 0.

30 The control valve 15 remains open until the suction tube 19 has been sucked empty.

The above-described resting state is then re-established.

- 18 In one special operating mode of the apparatus 70, the control valve 22 may be operated in time-controlled manner, such that the sprayed quantity of hydrogen peroxide is 5 halved per unit time. In this manner, it is possible to establish a desired profile of hydrogen peroxide gas levels. Figure 6 shows a further exemplary embodiment of an 10 apparatus 80 for volatilizing a decontamination agent in the form of hydrogen peroxide. The apparatus 80 differs from the apparatus according to Figure 5 in that it comprises two hydrogen peroxide vaporizers 74 connected in parallel, upstream of each of which there is connected a 15 venturi nozzle 83 or 84. The venturi nozzles 83 and 84 are connected, on the one hand, with the compressed air line 72 and, on the other, via a separate control valve 85 and 86 with the suction tube 19.

20 The two vaporizers 74 of the apparatus 80 furthermore each comprise a temperature sensor 76, which serves to determine the temperature of the associated vaporiser 74.

Downstream from each of the two vaporisers 74, there is 25 arranged a further temperature sensor 78 for determining the temperature of the mixture of hydrogen peroxide and compressed air.

Using this embodiment, it is possible to achieve twice the 30 suction power and thus twice the vaporiser output relative to the embodiment shown in Figure 5. Lower counterpressure is also achieved with vaporisers connected in parallel than

- 19 in the case of an embodiment with vaporizers connected in series. Figure 7 shows a further embodiment of an apparatus 100 for 5 volatilizing hydrogen peroxide. The apparatus 100 differs from that according to Figure 5 in that it comprises, upstream from the vaporiser 74, two venturi nozzles 101 and 102 connected in parallel, which are each connected with the compressed air line 72 The venturi nozzles 101 and 102 are furthermore each connected with the dispensing bottle 20 via a separate suction tube 103 and 104 which is at least in part flexible, a control valve 105 being arranged between the 15 tube 103 and the venturi nozzle 101 and a controlvalve 106 being arranged between the suction tube 104 and the venturi nozzle 102.

Figure 8 shows the hydrogen peroxide vaporiser 74 used in 20 the embodiments according to Figures 5 to 7. The hydrogen peroxide vaporiser consists of a vaporiser tube 110 taking the form of a smooth tube, into which flows the mixture of hydrogen peroxide droplets and air produced by means of the venturi nozzles. A swirl element 111 to impart turbulence 25 to the mixture is arranged in the vaporiser tube 110. The vaporiser tube 110 is surrounded by a cast aluminium component 112 in which is embedded a heating element 113, which coils in a spiral around the vaporiser tube 110. The cast aluminium component 112 is in turn enclosed in thermal 30 insulation 114 consisting of stationary air, said insulation being delimited by a housing 115.

- 20 The vaporiser furthermore comprises the temperature sensor 76 for determining the temperature of the vaporizer together with an electrical terminal box 117, which can be connected with a control unit not shown in greater detail 5 here.

The upstream and downstream ends of the vaporiser tube 110 are each provided with a screw fastening 118 or 119 for connection with adjacent components. In the present case, a 10 tube portion 122 is arranged downstream from the screw fastening 119, into which protrudes the temperature sensor 78 for determining the actual temperature of the hydrogen peroxide gas/air mixture flowing out of the vaporiser, said tube portion leading to a delivery line which in turn leads 15 to an isolator.

Claims

- 21 Claims

1. An apparatus for volatilizing a decontamination agent 5 with a compressed air source (12), a compressed air line (13), which leads to at least one decontamination agent vaporiser (17), together with a decontamination agent storage vessel (20), which is connected via a decontamination agent line (19; 103, 104) with the 10 decontamination agent vaporiser (17; 74), characterized in that the compressed air line (13; 72) opens into at least one venturi nozzle (14; 83, 84; 101, 102), which is connected with the decontamination agent line (19; 103, 104).

2. An apparatus according to claim 1, characterized in that a first control valve (22; 84, 86; 105, 106) is arranged in the decontamination agent line (19; 103, 104).

3. An apparatus according to claim 1 or 2, characterized in that a second control valve (15) is arranged in the compressed air line (13; 72) upstream from the venturi nozzle (14; 83, 84; 101, 102).

4. An apparatus according to one of claims 1 to 3, characterized in that a filter (16) is arranged in the compressed air line (13; 72) upstream from the venturi nozzle (14; 83, 84; 101, 102).

5. An apparatus according to claim 4, characterized in that an auxiliary venturi nozzle (31) is connected

upstream from the filter (16), into which nozzle opens a branch (32) of the decontamination agent line (19).

6. An apparatus according to claim 5, characterised in 5 that a third control valve (33) is arranged in the branch (32) of the decontamination agent line (19).

7. An apparatus according to claim 5 or 6, characterised in that the auxiliary venturi nozzle (31) is bridged 10 by a compressed air bypass (34) which comprises a fourth control valve (35).

8. An apparatus according to one of claims 1 to 7, characterised in that a filter (41) is arranged 15 between the venturi nozzle (14) and the decontamination agent vaporiser (17).

9. An apparatus according to one of claims 1 to 8, characterised in that the decontamination agent 20 vaporiser is composed of at least two individual vaporisers which are connected in series.

10. An apparatus according to one of claims 1 to 9, characterised in that the decontamination agent 25 storage vessel (20) is a dispensing bottle.

11. An apparatus according to one of claims 1 to 10, characterised in that the decontamination agent storage vessel (20) is equipped with a quantity 30 analysis device (21).

12. An apparatus according to claim 11, characterised in that the quantity analysis device (21) is a load cell.

13. An apparatus according to claim 11 or 12, characterised in that the quantity analysis device (21) cooperates with a metering device (22; 85, 86; 5 105, 106) which is arranged in the decontamination agent line (19; 103, 104).

14. An apparatus according to claim 12, characterised in that the metering device (22; 85, 86; 105, 106) is the 10 first control valve.

15. An apparatus according to one of claims 1 to 13, characterised in that the decontamination agent line (19; 103, 104) comprises a tube which, in the 15 operating position, is immersed in the decontamination agent storage vessel (20).

16. An apparatus according to claim 14, characterised by moving component (23) for immersing the 20 decontamination agent line (19; 103, 104) in the decontamination agent storage vessel (20).

17. An apparatus according to claim 15, characterised in that the moving component (23) is a lifting cylinder.

18. An apparatus according to one of claims 1 to 16, characterised in that the venturi nozzle (14; 83, 84; 101, 102) has a diffuser nozzle with a textured surface.

19. An apparatus according to one of claims 1 to 17, characterised in that the venturi nozzle (14; 83, 84;

- 24 101, 102) comprises a diffuser nozzle which is least in part temperature-controllable.

20. An apparatus according to one of claims 1 to 19, 5 characterized in that a temperature sensor (78) is arranged downstream from the decontamination agent vaporiser (17; 74).

21. An apparatus substantially as herein described with 10 reference to the accompanying drawings.