Inerting method and system for oxygen reduction

The invention relates to a neutralization method in which a predetermined oxygen content is determined and maintained in a closed room atmosphere, which is reduced compared to the normal oxygen content in ambient air and where, if necessary, the oxygen content in the atmosphere of the enclosed space may temporarily remain more reduced.

[0002] The invention also relates to an oxygen reduction device.

[0003] The neutralization system according to the invention optionally serves, for example, to reduce danger and to extinguish fires in a supervised protected room, with different levels of reduction to achieve permanent neutralization to prevent fires or fire fires in enclosed spaces.

[0004] As further examples of the reduction method according to the invention, it is described to provide training conditions in hypoxic situations in a closed room in which the oxygen content is reduced. In such a room it is possible to train in artificially created conditions of hypoxia, which is also referred to as "training in conditions of normobaric hypoxia". An example of use for storing food products, preferably stone fruit, under controlled atmosphere conditions (CA) is further mentioned, in which the percentage of oxygen in the air is regulated among others in order to slow down the process of perishable products.

[0005] The basic assumption of inerting technology for the prevention of fires is the observation that in confined spaces to which only people or animals enter from time to time and whose equipment is sensitive to water, the risk of a fire can be reduced so that the oxygen concentration in the affected area is reduced to an average content of, for example, 15% vol. volume. With this (reduced) oxygen concentration, most combustible materials can no longer ignite. The main field of application of inerting technology for prevention is, accordingly, also rooms with computer equipment, switching and electrical switchboards, closed facilities and storage rooms with valuable goods. Fire prevention that occurs with this method, essentially involves the suppression of oxygen. It is known that normal ambient air consists of 21% vol. oxygen, 78% vol. nitrogen and 1% vol. other gases. In order to prevent fires, a gas is introduced which displaces oxygen, for example nitrogen, which reduces the oxygen content in the atmosphere of a closed room. It is known that the fire prevention action takes place already when the oxygen content falls below about

15% volume Depending on the combustible materials contained in the room, it may be necessary to further reduce the oxygen content to, for example, 12% by volume.

[0006] Such a neutralization device is also known in principle from the prior art. For example, DE 198 11 851 A1 describes a neutralization device which has been designed to reduce the oxygen content in a closed room (hereinafter also referred to as a "protected room") to a specific basic level of neutralization and in the event of a fire further reduce the oxygen content to a certain level complete neutralization.

[0007] Under the term "basic neutralization" as used herein, oxygen should be understood to be reduced compared to the oxygen content in normal ambient air, but this reduced oxygen content does not yet mean a hazard to humans or animals, so that they may / they do not problems enter the protected room (ie without the need for special protective measures such as oxygen masks). The basic level of neutralization corresponds, for example, to the oxygen content in a protected room ranging from 15% to 17% by volume.

[0008] In contrast, the term "level of full neutralization" as compared to the oxygen content at the basic neutralization level should be understood as further reduction of the oxygen content at which the flammability of most materials is so limited that they can no longer ignite. Depending on the fire hazard in the protected room, the level of full neutralization is usually 12% - 14% vol. oxygen content.

[0009] In a multi-stage neutralization process known from DE 198 11 851 A1, in which the oxygen content is gradually reduced, neutralization technology for preventing fires is used, whereby the oxygen content in the protected room is first reduced to a lowered level (basic a level of neutralization) of, for example, 17% vol., in the event of a fire or demand, a further reduction of the oxygen content can be achieved to a certain level of full neutralization of, for example, 13.8% by volume. or below. If, in the case of such a two-stage neutralization, an inert gas generator, such as a nitrogen generator, is used to reduce the oxygen content to the first reduction level (basic neutralization level),

[0010] In order to be able to use the two-stage neutralization process described above and known per se, relatively high investment costs are necessary, because a two-stage neutralization process places particular demands on the sources of inert gas needed to produce an inert gas. Specifically, two separate sources of neutralizing gas have been placed in conventional two-stage neutralization equipment, because in order to establish a certain level of neutralization (reduction level) it is necessary to distinguish whether a basic or full level of neutralization should be achieved in the atmosphere of the room. It should be taken into account that starting from the already set basic level of neutralization, the reduction to the full level of neutralization must take place according to a predetermined sequence of events, especially during a specified period of time after the alarm. However, to establish a basic level of neutralization, it is not necessary to proceed according to a specific neutralization curve.

[0011] The term "neutralization curve" as used herein is understood to mean a change in the oxygen content over time when introducing oxygen displacing gases (neutralizing gases) into the atmosphere of a protected room.

[0012] Because in order to determine a certain level of inertiation, it has to be distinguished whether a basic or total level of neutralization has to be applied in the atmosphere of the room, there are various requirements for sources of inert gas that must provide a neutralizing gas to establish the basic or full level of neutralization. With regard to the source of the inert gas to be used, it should be taken into account that in a given unit of time it would be able to provide a sufficiently large amount of antacid to achieve a level of complete neutralization in the atmosphere of the protected room within a given period of time. The used source of antacid must therefore have a capacity to reduce the oxygen content to the level of full neutralization.

[0013] However, this requirement does not apply in cases where only the basic level of neutralization is assumed to be achieved. As already mentioned, it is usually not necessary that the reduction to the basic level of neutralization must be carried out according to a predetermined neutralization curve, especially within a certain time interval. Therefore, the source of neutralizing gas used to reduce to the basic level may be correspondingly smaller in terms of its output power.

In the practical application of a two-stage neutralization process, two separate sources of neutralizing gas are used for these reasons: a nitrogen generator that can deliver a relatively small amount of antacid (here: nitrogen enriched air) per unit of time and is used to produce and maintain a basic level of neutralization and a container with high pressure gas in which the gas or a mixture of antacid gases is stored in a compressed form to temporarily achieve a level of complete neutralization in the atmosphere of a closed room.

[0015] The use of two separate sources of neutralizing gas to carry out the two-stage neutralization process has the disadvantage that the initial investment costs are relatively high. In addition, the preparation of a room where both separate sources of antacid should be located (a nitrogen generator on the one hand and a container with pressurized gas on the other side) in some cases require a larger amount of construction.

[0016] Publication WO 2012/076721 A1 relates to a neutralization process with features according to the preamble of independent patent claim 1.

[0017] It is on the basis of this object of the invention to provide a neutralization or neutralization device in which the operating costs and initial investment compared to traditional solutions can be reduced without affecting the performance of the device.

This object is achieved with respect to the method by the subject matter of the independent patent claim 1 and with respect to the device (oxygen reduction device) by the subject matter of the independent patent claim 10.

[0019] With respect to the method according to the invention, the preferred embodiments are defined in claims 2 to 9. Preferred embodiments of the neutralization device according to the invention are defined in the dependent claims 11 to 13.

[0020] In accordance with the invention, in particular, an oxygen reduction device is proposed in which a reduced oxygen content is achieved and maintained in a closed room atmosphere, when compared to normal ambient air. The device includes a compressor system for compressing the initial mixture and a gas separation system connected to the compressor system, in which at least part of the oxygen contained in the compressed initial mixture is separated. The gas separation system has been designed to operate in the optional VPSA or PSA mode.

[0021] The term "starting mixture" as used herein is generally understood to mean a gas mixture which in addition to the oxygen content contains in particular nitrogen and optionally other gases, such as, for example, noble gases. As an initial gas mixture, for example, normal ambient air is used, i.e. a gas mixture of 21 vol.%. oxygen, 78% vol. nitrogen and 1% vol. other gases. However, it is possible to solve, where the initial mixture consists partly of the air contained in the room, while the air is preferably mixed with fresh air.

[0022] Under the term gas separation system operating in the VPSA mode, it is generally understood to be a device operating under the principle of Vacuum Pressure Swing Adsorption (VPSA) and producing nitrogen-enriched air. According to the invention, in a neutralization device operating in the VPSA mode, a gas separation system is used, which if necessary can operate in PSA mode. The abbreviation "PSA" means "Pressure Swing Adsorption", which means pressure swing adsorption.

[0023] In order to be able to switch the operating mode of the gas separation system from VPSA to PSA used in the solution according to the invention, the method according to the invention provides that the compression ratio produced by the initial mixture compressor system will be increased accordingly. In particular with respect to the neutralization process according to the invention, it is anticipated that an initial mixture containing oxygen, nitrogen and optionally other ingredients is first produced. The initial mixture thus formed is suitably compressed in a compressor system and then fed to a gas separation system in which at least a portion of the initial oxygen contained in the compressed mixture is separated so that a nitrogen enriched gas mixture is formed at the outlet of the gas separation system. This gas separation system produced at the exit,

According to the invention, it is particularly contemplated that when the amount of nitrogen enriched mixture, produced in a unit of time at the outlet of the gas separation system, is increased, the compression ratio of the compressor system is increased, especially to a value which depends on the amount a mixture of nitrogen-enriched gases, produced in a unit of time. In this way, the operating mode of the gas separation system can be changed so that the amount of gas mixture enriched with nitrogen actually produced at the output of the gas separation system corresponds to the preset amount of nitrogen enriched gas mixture produced per unit time.

The increase in the compression of the initial mixture, carried out by the compressor system, takes place in particular in the event of a fire, i.e. when, for example, fire parameters are detected in a closed atmosphere, or if for some reason the oxygen content is temporarily in a closed atmosphere, in comparison with the previously set or maintained oxygen content, it should be further reduced.

According to a further feature of the invention, the compression ratio of the initial gas mixture, carried out by the compressor system, is increased if the amount of nitrogen enriched gas mixture generated at the exit of the gas separator system has to be increased due to the increased air exchange. In accordance with another feature of the invention, the compression ratio of the initial mixture carried out by the compressor system is increased because of the downstream failure of the inert gas source, especially in the event of a downstream fault associated with the gas separation system, the amount of gas mixture nitrogen-rich gas, produced at the output of the gas separation system per unit of time, must be increased.

In particular in the event of a fire or for a different reason, temporarily in a closed atmosphere, oxygen content should be further reduced, the degree of compression of the initial gas mixture is increased to a value which depends on the amount of gaseous mixture produced per unit of time. in nitrogen. In an embodiment, it is therefore not possible to increase the compression rate from the original 1.5 to 2.0 bar up to 7.0 to 9.0 bar. In other embodiments, an increase in compression to 25.0 bar is also possible. The invention is not particularly limited to the exemplary values ​​given above.

The solution according to the invention is based on the knowledge that a gas separation system that operates in PSA mode can produce a sufficient amount of nitrogen-enriched gas per unit of time to reduce the oxygen content in a closed room as soon as possible in the shortest possible time. the set level of basic reduction to the full level of reduction. On the other hand, when the gas separation system operates in VPSA mode, the amount of nitrogen-enriched gas supplied to the gas separation system output in a given time unit is significantly lower compared to the case when the gas separation system operates in PSA mode. This amount of nitrogen-enriched gas at the outlet of the gas separation system per unit of time in the VPSA mode is, however, generally sufficient,

[0029] The gas separation system used in the solution according to the invention thus fulfills a dual function: if the gas separation system is operated in the VPSA mode, the first source of neutralizing gas is included in the system, applicable to conventional devices by means of which it is possible providing the inert gas necessary to achieve or maintain a basic level of neutralization. However, in PSA mode, the output efficiency of the gas separation system corresponds to the efficiency of the high pressure gas container that is used in conventional two-stage neutralization devices as a second source of neutralizing gas to form a neutralizing gas for complete neutralization.

[0030] In order to be able to increase the compression ratio of the initial mixture by the compressor system, if the compressor system comprises a first compressor and at least one second compressor, the second compressor is optionally connected to the second compressor, the overall compression achieved can be increased. In particular, it is therefore possible when the first and the second compressors work independently of one another, the first compressor being connected in series with the other so that by adding the second compressor the compression ratio of the initial gas mixture is increased. Of course, however, other embodiments for selectively increasing the degree of compression are acceptable.

In the embodiments of the neutralization device according to the invention, it is envisaged that in the event of a fire the compression ratio, carried out by the compressor system, is increased, preferably gradually, that the amount of nitrogen gas enriched in the unit of time per unit time equals the amount of nitrogen enriched gas mixture to be produced per unit of time. In this embodiment, a regulation is provided that ensures that at any time the gas separation system produces exactly the amount of nitrogen enriched gas mixture that is actually needed.

[0032] According to one feature of the invention, it is envisaged that a compressor system is implemented which, if necessary, compresses the starting gas mixture to a variety of preferably pre-determined or determinable pressure ranges. It is therefore advantageous if, depending on the cause or the reason for the prescribed increase in the nitrogen-enriched gas mixture produced in a time unit at the exit of the gas separation system, compression of the initial gas mixture preferably takes place automatically and more preferably optionally automatically to predetermined or determinable ranges pressure.

[0033] The solution according to the invention has a number of advantages over prior art conventional two-stage neutralization devices. In that only one source of neutralizing gas in the form of a gas separation system with variable mode of operation is used to achieve / maintain a basic level of neutralization, as well as to achieve / maintain the level of full neutralization, initial investments related to a neutralization device compared to conventional solutions they are significantly reduced because it is not necessary to provide two separate sources of antacid. For the same reasons, the demand for space is also reduced,

[0034] On the other hand, the solution according to the invention is characterized in particular by the fact that the gas separation system with variable operation mode is particularly energy-saving and thus causes low current operating costs. The gas separation system can also easily be installed in particularly limited space conditions and operates reliably, automatically and without constant supervision, which makes the solution according to the invention particularly easy to operate. Energy efficiency is thus ensured that the gas separation system in the VPSA mode works extremely efficiently at low energy costs, because the compressor system must produce a comparatively small degree of compression. Only in exceptional cases,

In a preferred embodiment according to the invention, in order to produce an initial gas mixture in a controlled manner, a part of the air is removed from the enclosed space, this removed portion of air being also preferably in a controlled manner discharged into the fresh air. For this purpose, it is best to install a mixing chamber in front of the compressor system, in which fresh air is supplied to the removed part of the air in the room. Preferably, fresh air is supplied in a controlled manner to the removed part of the air in the room.

"In a controlled manner" means in this context that in the mixing chamber per unit of time only so much fresh air is supplied in place of the removed part of the room air, that in the unit of time at the output of the gas separation system, the amount of nitrogen enriched gas is produced preferably corresponds to the amount of gas removed from a closed room per unit of time. In this way, it can be achieved that in a closed room the pressure will remain unchanged, especially that no leakage will be created or that no gas will be produced at the exit of the gas separation system and too much nitrogen enriched gas will enter the room, which would be disadvantageous due to energy efficiency.

For the technical implementation of the gas separation system applicable to the solution according to the invention, it is possible to place on the outer surfaces membranes of fibers of the separation material through which water vapor and oxygen diffuse very well, whereas nitrogen has a low diffusion velocity relative to this separation material. If an initial gas mixture passes through such fibers, water and oxygen diffuse very quickly through the fiber layer outwards, while nitrogen is largely retained in the fibers so that high nitrogen concentrations occur during the passage through the capillary fibers. The efficiency of this separation process depends to a large extent on the flow velocity in the fibers and the pressure difference acting on the capillary fibers.

[0038] With respect to the solution according to the invention of the gas separation system used, various embodiments are possible. In one particularly simple embodiment, the gas separation system is made as a so-called one-stage system, wherein the gas separation system comprises one container with an adsorbent. When referring to the adsorbent material, (sometimes also referred to as the "adsorbent support") it is preferably a synthetic zeolite or a carbon molecular sieve. Knowledge is used here that different gases with different velocity diffuse through the materials. The proposed current gas separation system uses different diffusion rates of the main components of the initial gas mixture, namely nitrogen, oxygen and possibly water vapor, technically for the production of a nitrogen enriched gas mixture.

For the technical implementation of the gas separation system applicable to the solution according to the invention, it is possible to place a separation material on the outer surfaces of the capillary fiber membranes, through which water vapor and oxygen diffuse very well, whereas nitrogen has only a diffusion velocity relative to this separation material. . When the starting gas mixture passes through such capillary fibers from the inside, water vapor and oxygen diffuse quickly through the capillary fiber walls outwards, while nitrogen is largely retained inside the fibers, such that a strong accumulation of nitrogen takes place during the passage through the capillary fibers. The effectiveness of this separation process depends to a large extent on the flow velocity in the fibers and the pressure difference acting on the capillary fiber walls.

[0040] As already mentioned, in a simple embodiment of the solution according to the invention it is provided that the gas separation system is made as a single-flow system, wherein the compressor system can be connected to the entrance of the (sole) adsorbent container so that during the adsorption phase of the container with the adsorbent into the container with the adsorbent compressed initial gas mixture, so that oxygen from the initial gas mixture is adsorbed by the adsorbent material and at the exit of the container with the adsorbent a nitrogen enriched gas mixture is produced, which is ultimately fed to a closed room. In this case, regeneration of the adsorption material may occur by lowering the pressure to ambient pressure so that the oxygen so far bound in the adsorption material to the outside atmosphere.

[0041] Alternatively, it is possible, however, that in the case of a gas separation system designed as a one-stage system, regeneration of the adsorption material takes place under negative pressure. In this case, a vacuum cycle is used for regeneration, in which the source of compressed air is connected for the regeneration with the output of the container with the adsorbent, so that at least a part of the previously absorbed oxygen can be discharged through the container with the adsorbent and thus regenerate the adsorbent material.

[0042] In order to achieve that a closed room without a low-pressure buffer container can be provided with a nitrogen-enriched gas (neutralizing gas), an alternative embodiment of the solution provides that the gas separation system is made as a two-stage system. In this case, the gas separation system comprises a first and a second container with an adsorbent, each of which comprises an adsorbent layer or adsorbent material. At least in the normal mode of operation of the neutralization device, i.e. in particular when there is no fire in a closed room, both adsorbent containers preferably operate in counterphase so that one of the adsorbent containers is in the adsorption phase, during which the adsorbent material of the respective container with the adsorbent adsorbs at least some of the oxygen from the initial mixture fed. The second of both adsorbent tanks is in the regeneration phase, during which the adsorbent material of this second reservoir with the adsorbent is regenerated. Due to alternating successive stages, one of the adsorbent containers always absorbs oxygen, while the other, thanks to desorption, is purified. In this way, at the outlet of the gas separation system, the nitrogen-enriched gas is constantly present and has almost constant pressure and purity. Due to alternating successive stages, one of the adsorbent containers always absorbs oxygen, while the other, thanks to desorption, is purified. In this way, at the outlet of the gas separation system, the nitrogen-enriched gas is constantly present and has almost constant pressure and purity. Due to alternating successive stages, one of the adsorbent containers always absorbs oxygen, while the other, thanks to desorption, is purified. In this way, at the outlet of the gas separation system, the nitrogen-enriched gas is constantly present and has almost constant pressure and purity.

[0043] As already mentioned, for reasons of energy efficiency and because of the low costs of current use, it is advantageous if the gas separation system normally operates in VPSA mode, but only in the event of a fire or for some other reason temporarily oxygen content in the atmosphere. the closed room compared to the pre-set or maintained oxygen content can be further reduced, the gas separation system works in PSA mode.

In particular, it is possible here that in the VPSA operating mode of the gas separation system the compressor system is controlled such that the initial gas mixture is compressed to an atmospheric overpressure of 1.5 to 2.0 bar. At relatively low atmospheric overpressure, it is possible to separate gases according to the VPSA principle. If in this case the gas separation system has been designed as a two-step system, an adsorption and desorption cycle is preferably used, with a pressure change mechanism between atmospheric overpressure of 1.5 to 2.0 bar and atmospheric vacuum (vacuum) of about 0 , 2 to 0.85 bar, both adsorbent containers act alternately in the adsorption cycle or desorption cycle.

In the event of fire or other reasons, temporarily being able to increase the amount of nitrogen enriched gas produced in the unit of time at the output of the gas separation system, the gas separation system is switched from VPSA mode to PSA mode and so that at the entry of the separation system The initial gas mixture with atmospheric overpressure of 7.0 to 9.0 bar is produced.

It is of course also possible that also in the PSA operation mode of the gas separation system, one of the two adsorbent containers is operated in the desorption cycle, while the other of the two desorbent containers operates in the adsorption cycle.

[0047] In order to optimize the efficiency of the gas separation system, it is advantageous if the initial gas mixture heated to a temperature of 10 ° C to 30 ° C, more preferably at a temperature of 15 ° C to 25 ° C is fed into the gas separation system. In order to be able to heat up the initial gas mixture in the most efficient way, in a preferred embodiment according to the invention a heat exchange system is provided that is designed to carry at least part of the gas separated during operation in a gas separation system and / or in a heat energy compressor system (heat loss) to the initial gas mixture.

In addition or as an alternative to this embodiment, the embodiment according to the invention provides that also the nitrogen-enriched gas mixture produced at the exit of the gas separation system is heated by means of at least part of the heat energy released in the gas separation system and / or in the compressor system . For this purpose, it is possible, in particular, to provide an additional heat exchanger system. In that the nitrogen-enriched gas and the gasification system produced at the exit are heated before the enclosed room is introduced into the atmosphere, it can be achieved that the nitrogen enriched gas mixture is distributed by thermal convection relatively quickly in a closed atmosphere so that it can be achieved consistently uniform level of reduction. In particular, it is not necessary that the mixture enriched with nitrogen at relatively high pressure is introduced into a closed room to ensure that the atmosphere of the room is mixed. The introduction of high pressure gas is disadvantageous for reasons of energy efficiency and in certain circumstances also has other negative features, in particular related to the expected pressure drop.

[0049] In order to achieve a level of full neutralization even more rapidly in the enclosed space, if necessary, in a preferred embodiment of the invention, a catalyst system is provided in addition to the gas separation system. This catalyst system has been made so that a neutralized gas mixture can be produced by chemical conversion of the reducing agent. In particular, it is possible that at least a portion of the nitrogen enriched gas mixture that is generated at the exit of the gas separation system and / or part of the contained air is supplied to the catalyst system, if necessary, to obtain a neutralized chemical transformation of the reducer in the catalyst system. a mixture that is then introduced into the atmosphere of a closed room.

In a preferred embodiment of the last-mentioned embodiment, in which a catalyst system for the immediate production of a neutralizing gas is used in the gas separation system, it is used as a reducer which in the catalyst system undergoes chemical conversion, a combustible material, in particular a combustible gas, preferably an oxide coal.

[0051] Next, various embodiments of the invention will be described based on the attached drawing.

[0052] They show:

Fig. 1 a schematic view of a first embodiment of a neutralization device according to the invention;

Fig. 2 a schematic view of a second embodiment of the neutralization device according to the invention;

Fig. 3 a schematic view of a third embodiment of a neutralization device according to the invention;

Fig. 4 a schematic view of a fourth embodiment of a neutralization device according to the invention

Fig. 5 a schematic view of another embodiment of a neutralization device according to the invention;

[0053] Fig. 1 schematically shows a first embodiment of the neutralization device 1 according to the invention. The presented neutralization device 1 serves to achieve and maintain a predetermined level of reduction (level of neutralization) in the atmosphere of the enclosed room 2. The enclosed space 2 may be, for example, a warehouse in which, for example in the context of fire-prevention measures, the oxygen content in the air has been lowered to a specified (basic) level of inertization for example, 15% volume.

[0054] The inerting device 1 in the embodiment shown in Fig. 1 comprises a compressor system 3, whose inlet 3a is in fluid communication with the closed room 2, so that by means of a compressor system 3, the air from the inside of the closed room 2 is sucked. The outlet 3b of the compressor system 3 is in fluid communication with the input 10a of the gas separation system 10, possibly connected to it. In this way, compressed air can be supplied to the gas separation system by means of a compressor system 3, which has previously been removed from the enclosed space 2.

Of course, it can also be provided that in the case of a mixture fed to the entrance 3a the compressor system 3 is fresh air, so that the return line between the closed room 2 and the input 3a of the compressor system 3 can be dispensed with. In particular, in this embodiment, it is advantageous if in this enclosed space 2 there is a pressure reducer, for example in the form of one or more pressure valves.

[0056] In order to prevent the room pressure from evacuating from the enclosed space 2, the space 2a of the enclosed space 2 is preferably provided with ventilation openings (not shown in Fig. 1). Here, it can be a naturally occurring leak in the space of room 2a or also with specially installed load holes.

[0057] The schematic illustrated in FIG. 1 is a gas separation system for producing a nitrogen enriched mixture at exit 10b from a gas separation system. In particular, a gas separation system was designed, from which, via the compressor system 3, at least a portion of the oxygen contained therein is separated off in the incoming compressed initial mixture. The oxygen separated from the initial mixture is transferred via degassing lines 11 to the outside atmosphere.

The nitrogen-enriched mixture, which is produced at the exit 10b of the gas separation system 10, is then introduced into the atmosphere of the enclosed space 2, preferably in a controlled manner such that a reduced oxygen level in the atmosphere of the enclosed space 2 is set and compared to normal ambient air 2 achieved and maintained.

If the oxygen content in the room atmosphere detected by the oxygen content measuring device 5 exceeds the setpoint specified for the control device 4, the control device 4 switches on automatically, and more preferably optionally automatically the compressor system to create a compressed initial gas mixture. In this way, a nitrogen-enriched gas is produced at the exit 10b of the gas separation system 10, so that the oxygen content in the room atmosphere can be further reduced, when a nitrogen-enriched gas mixture is generated at the outlet 10b of the gas separation system 10a. and even more preferably an optional automatic compressor system to create a compressed initial gas mixture. In this way, a nitrogen-enriched gas is produced at the exit 10b of the gas separation system 10, so that the oxygen content in the room atmosphere can be further reduced, when a nitrogen-enriched gas mixture is generated at the outlet 10b of the gas separation system 10a. and even more preferably an optional automatic compressor system to create a compressed initial gas mixture. In this way, a nitrogen-enriched gas is produced at the exit 10b of the gas separation system 10, so that the oxygen content in the room atmosphere can be further reduced, when a nitrogen-enriched gas mixture is generated at the outlet 10b of the gas separation system 10a.

However, if the oxygen content measured in the control device 4, compared to the set value, shows that the predetermined value has already been exceeded, the compressor system is switched off by means of the control device 4 so that no gas is produced at the outlet 10b of the gas separation system 10 nitrogen-rich. During the normal operation of the neutralization device 1, i.e. when a basic level of neutralization is to be created or maintained in a closed room 2, an initial gas mixture having an atmospheric pressure of, for example, 1.5 to 2.0 bar is fed to the gas separation system. The relatively low inlet pressure is generated by the compressor system 3 system.

[0061] As shown in Fig. 1, the neutralization device 1 according to the invention 1 is further preferably equipped with an aspiration-seeking fire detection system that includes at least one fire detection sensor 6. This fire detection sensor 6 in the illustrated embodiment is combined It is controlled via the control line with the control device 4. With the help of the fire parameter recognition system, it is checked permanently whether a fire has occurred inside closed room 2 or when certain events have occurred. When detecting fire parameters, the fire parameter sensor 6 emits a corresponding signal on the control device 4. The control device 4 then automatically initiates the full neutralization of the enclosed room 2 automatically,a level of full neutralization of, for example, 12% vol., depending on the fire hazard in the room 2.

The solution according to the invention is characterized in that in the neutralization device 1 only a single source of neutralizing gas is used (here: separation system 10 with a connected compressor system 3), whereby the efficiency of the gas separation system can be appropriately increased if necessary. and in the shortest possible time the amount of nitrogen enriched gas needed for complete neutralization can be generated at the output 10b of the gas separation system 10b.

[0063] As will be described below with reference to Figures 2 to 4, the gas separation system is preferably a one-stage nitrogen generator (see Figure 4) or a two-stage nitrogen generation system (see Figures 2 and 3 ), with these generators optionally operating in PSA mode or in VPSA mode. In the PSA mode, a compressed initial gas mixture is supplied to the gas separation system, for example at a pressure of 7.0 to 9.0 bar, whereby a gas quantity which can be produced per unit of time at the outlet 10b of the gas separation system 10 is provided. nitrogen enriched can be significantly increased compared to the VPSA operating mode. In the VPSA operating mode, the compression ratio of the initial mixture is for example only 1.5 to 2.0 bars.

[0064] In Fig. 2 is a schematic view of an exemplary embodiment of a neutralization device 1 according to the invention in which a two-stage nitrogen generator is used as the gas separation system. The two-stage system is characterized in that the first and second adsorbent reservoirs 12, 13 are placed, in which the adsorption layer or the adsorbent material respectively are located. If the initial mixture of gases through the adsorbent material is introduced into the container with the adsorbent 12, 13, the adsorbent adsorbs at least part of the oxygen contained in the initial mixture, such that a nitrogen-enriched gas mixture is produced at the outlet 12b, 13b of the corresponding container with the adsorbent 12, 13 .

[0065] In the case of the two-stage system shown in Fig. 2, an embodiment, both containers with adsorbent 12, 13 are arranged parallel to each other so that they can be driven in counterphase. The phase feed drive means that one of the two containers with the adsorbent 12, 13 is in the adsorption phase, in which the adsorbent material of the respective container with the adsorbent 12, 13 adsorbs at least some of the oxygen from the initial mixture fed. The second of the two tanks with the adsorbent 13, 12 is in the regeneration phase, during which the adsorbent material of the second tank with the adsorbent 13, 12 is regenerated. Because of successive stages, one of the two adsorbent containers always adsorbs oxygen, while the other is cleaned by desorption.

In particular and as can be seen from the pneumatic diagram of Fig. 2, the entrance 12a of the first container with the adsorbent 12 can be connected via the valve V1 to the output 3b of the compressor system 3, located on the pressure side, while the outlet 12b of the first container with The adsorbent 12 can be connected via a valve V2 to the output 10b of the gas separation system 10. In the same way, the input 13a of the second container with the adsorbent 13 above the valve V4 can be connected to the discharge outlet 3b of the compressor system 3 and the output 13b of the second container with the adsorbent 13 above the valve V5 can be connected to the gas separation system output 10b.

[0067] Further, the input 12a of the first adsorbent vessel 12 above the valve V3 and the input 13a of the second container with the adsorbent 13 above the valve V6 can be connected to the suction side 7a of the vacuum source 7.

[0068] In order to be able to vary the compression ratio of the initial mixture obtained in the compressor system 3, it is possible to use, as a compressor system, a frequency controlled compressor. In the embodiment shown in FIG. 2, on the contrary, the compressor system 3 consists of a plurality of individual compressors 3.1, 3.2 (here two) connected in series. By including both compressors 3.1, 3.2, an initial mixture is created in the highly compressed form at the outlet 3b of the compressor system 3, while the compression ratio of the initial mixture is reduced accordingly when only one of the compressors 3.1, 3.2 is switched on. Of course, it is possible to use many individual compressors that are not connected in series, but by adding additional compressors, the degree of compression can be increased.

[0069] Furthermore, the embodiment shown in Fig. 2 shows an additional blast 20 arranged in the return circuit 19 between the closed room 2 and the entrance 3a of the compressor system 3.

In the VPSA operating mode of the gas separation system 10, according to the embodiment of the neutralization device 1 according to the invention shown in FIG. 2, one of the two containers with the adsorbent 12, 13 operates in the adsorption cycle and at the same time the second with both adsorbent containers 13 , 12 operates in a vacuum cycle to be able to achieve the regeneration state of the relevant adsorption material. In the adsorption cycle of the first container with adsorbent 12, the valve V1 is open so that the output 3b on the pressure side of the compressor system 3 is in fluid communication with the input 12a of the first container with the adsorbent 12. The initial gas mixture compressed in the compressor system 3 is thus fed into the first container container with adsorbent 12.

[0071] During the operation of the second container with the adsorbent 13 in the vacuum cycle, located at the outlet 13b of the second container with the adsorbent 13, the valve V5 is closed. Likewise, a second container with adsorbent 13 of valve V4 at the input 13a is closed so that the second container with adsorbent 13 is not in fluid communication with the outlet 13b on the pressure side of the compressor system 3. However, the second container with the adsorbent 13 is located at the entrance 13a V6 is open and the first container 12a on the first container with adsorber 12 of the V3 valve and located on the second input 13a into the container with the adsorbent 13 of the valve V4 are closed.

In this way, the entrance 13a of the second container with the adsorbent 13 is in fluid communication with the input 7a located on the suction side of the vacuum source 7, so that at least some of the oxygen absorbed by the adsorbent material of oxygen, located in the second container with the adsorbent 13, is desorbed, and from the second container with the adsorbent by means of a vacuum source 7 and through the outlet 7b of the vacuum source 7 is discharged into the ambient air.

[0073] After regeneration of the adsorbent material of the second container with the adsorbent 13, the second container with the adsorbent 13 operates in the adsorption cycle, while the first container with the adsorbent 12 is switched to the desorption cycle. For this purpose, the valves V1, V2 and V6 are closed and the valves V3, V4 and V5 are open. Then, the initial mixture compressed in the compressor system 3 flows through the adsorbent material of the second container with the adsorber material 13, hence a nitrogen-enriched gas is produced at the outlet 13b of the second container with the adsorbent 13. On the other hand, the previously adsorbed oxygen in the first container with the adsorbent is at least partly sucked through the vacuum source 7 and discharged into the outside air, so that regeneration of the adsorbent material takes place in the first container with the adsorbent 12.

It is particularly advantageous if the input 12a of the first container with the adsorbent 12 can be connected through the valve V7 directly to the input 13a of the second container with the adsorbent 13, and the outlet 12b of the first container with the adsorbent 12 via the valve V8 with the outlet 13b of the second container with 13. By providing this valve V7, V8 in particular it is possible, before switching between the adsorption phase and the regeneration phase, short the respective inputs 12a, 13a and the corresponding outputs 12b, 13b of both containers with the adsorbent 12, 13 for a short time (preferably 0, 5 to 2 seconds). In this way, a pressure equalization between the two containers with the adsorbent 12, 13 can be obtained,

[0075] The individual controlled elements of the neutralization device 1 according to Fig. 2 are suitably controlled by the controller 4. Here, in particular, the valves V1 to V9, the compressor system 3, the vacuum source 7 and the air supply 20.

If, in the event of a fire or other reason, the oxygen content in the atmosphere of the enclosed space 2 temporarily must be lowered in comparison with the previously set or maintained reduced oxygen content, it is recommended to provide a time unit 10b for the separation unit 10b gases a greater amount of nitrogen enriched gas.

[0077] To be able to achieve this by means of a gas separation system, as shown in Fig. 2, the control device 4 controls the compressor system 3 to increase the compression ratio of the initial mixture. It should be taken into account that in the previously described VPSA mode, the initial mixture is compressed to an atmospheric pressure of 1.5 to 2.0 bars. The vacuum source 7 creates a negative pressure of, for example, 0.2 to 0.85 bar. By increasing the compression ratio of the compressor system 3 to an atmospheric pressure of, for example, 7.0 to 9.0 bar, the amount of gas flowing in the time unit through the reservoir with the adsorbent 12,13 is increased, and consequently also at the outlet 10b of the gas separation system 10 in the unit. time much more nitrogen-enriched gas is produced.

[0078] In PSA operating mode, in which the initial mixture is compressed by a compressor system 3 to those described in example 7.0 to 9.0 bar with respect to the atmosphere, it is generally also possible for both containers with adsorbent 12, 13 to work alternately in the adsorption and regeneration cycle. When in the PSA operating mode the first container with the adsorbent 12 is operating in the adsorption cycle, then the valves V1 and V2 are open and the valve V3 is closed. The initial mixture compressed to high atmospheric pressure then flows through the adsorbent material of the first container with the adsorbent 12, so that at the output 12b of the first container with the adsorbent 12 a correspondingly large amount of oxygen-enriched gas is produced per unit of time.

[0079] In the desorption cycle of the second container with the adsorbent, the valves V4 and V5 are closed and the valve V6 is open. In addition, the vacuum source 7 is turned off so that the oxygen so far bound in the adsorption material is expelled and through the outlet 13a of the second adsorbent container 13 and through the switched vent valve V6 enters the outlet 7b of the vacuum source 7, where it enters the outside atmosphere.

In the embodiment of the inertization device according to the invention shown in FIG. 2, it is anticipated that the initial mixture is produced at the intake port 3a of the compressor system 3 so that part of the air contained in the enclosed space is removed from room 2 and instead of Fresh air is introduced into the room.

[0081] For this purpose, a fresh air blast 8 has been designed, the power of which can be set by means of the control device 4. By blowing fresh air 8 fresh air enters the mixing chamber 9, in which fresh air and room air are mixed. From the mixing chamber 9, using the compressor system 3, the initial mixture prepared in this way is sucked off.

[0082] With the control device 4, the amount of fresh air that is mixed with the air removed from the room 2 is selected so that the amount of air removed from the room 2 per unit of air time is identical to the amount of nitrogen enriched mixture that has been removed from the atmosphere rooms 2.

[0083] In the embodiment of the neutralization device 1 according to the invention, the first heat exchanger 14 is used, and at least part of the thermal energy generated during the operation of the gas separation system and / or the compressor system is transferred to the initial mixture. In particular, the first heat exchanger system 14 is thus configured and dimensioned so that the temperature of the initial gas mixture can preferably be lowered to 10-30 ° C, and even more preferably to 15-25 ° C. At these temperatures, the adsorption material of the gas separation system works most efficiently.

In the embodiment shown in FIG. 2, the neutralization device 1 according to the invention is further provided with a second heat transfer system 15, which serves to allow at least part of the heat energy released in the gas separation system and / or the compressor system 3 to be transferred to a gas separation system 10a obtained at the output 10b, a nitrogen-enriched gas mixture. By introducing the pre-heated gas mixture enriched with nitrogen in this way to the closed room 2, it is advantageously possible to achieve a condition where this supplied and nitrogen-enriched mixture, due to natural convection, mixes very well and rapidly inside the room 2. In particular by regulating the temperature supplied gas mixtures can be dispensed with under pressure.

[0085] The neutralization device 1 depicted in Fig. 3 substantially corresponds to the device described above with reference to the apparatus shown in Fig. 2, in addition to which the first catalyst system 16 is used for the gas separation system 16. The first catalyst system 16 serves to if necessary, a neutralized gas mixture may be obtained from the gas separation system 10 produced at the exit 10b and the nitrogen-enriched gas mixture by chemical transformations of the reducing agent. Particularly in the catalyst by chemical conversion of the reducing agent, in particular a combustible material, such as carbon monoxide, which at the output 10b of the gas separation system 10 produces a nitrogen-enriched gas mixture that converts into a neutralized mixture.

The second catalyst system 17 is also shown in the embodiment of the neutralization device 1 shown in Fig. 3. In contrast to the first catalyst system 16, a portion of the air contained in the closed room 2 is directly supplied to the second catalyst system 17, The enclosure 2 and the catalyst system 17 are provided with an additional blow 21, which can be controlled by a control device 4. In the catalyst system 17, a chemical mixture of the reducer, in particular carbon monoxide, is produced, which eventually enters the atmosphere of the enclosed room 2 .

[0087] Suitable catalyst systems 16, 17 are connected whenever the amount of nitrogen enriched gas, capable of being produced per unit of time by the gas separation system, is insufficient to achieve and / or maintain an appropriate level of reduction in the atmosphere of the enclosed space (2). ).

[0088] The neutralization device 1 shown in Fig. 4 essentially corresponds to the device described above with reference to the illustration in Fig. 3, wherein only the one-stage system is used as a gas separation system. In other words, the gas neutralization system 10 of the neutralization apparatus 1 according to Fig. 4 contains only one adsorption vessel 12 which from the input side is connected above the valve V1 with the discharge outlet 3b of the compressor system 3. Above the valve V2 the output of the adsorption container can be connected 12 with output 10b of the 10 gas separation system. In addition, at the entrance 12a of the adsorbent container 12, a valve is shown allowing, if necessary, the connection 12a of the adsorption container 12 to the suction side of the vacuum source 7.

[0089] As with the neutralization systems 1 previously described with reference to Figs. 2 and 3, the embodiment of the gas separation system shown in Fig. 4 operates in the adsorption cycle and in the regeneration cycle or vacuum cycle. In the adsorption cycle, in this case the valves V1 and V2 are open and the valve V3 is closed. In order to regenerate the adsorbent, the valves V2 and V1 are closed while the valve V3 is open. By means of vacuum sources, 7 is removed from the adsorbent container 12, previously absorbed by the adsorbent material, oxygen.

[0090] To increase the output power of the gas separation system, in the embodiment shown in Fig. 4, the compressor system 3 is increased by means of the control device 4, for example from the primary from 1.5 to 2.0 bar up to 7.0. up to 9.0 bars of atmospheric overpressure.

[0091] In order for the single-phase system of Fig. 4 to enable the nitrogen gas to be continuously produced, a low-pressure buffer tank 18 is provided that can be connected via a valve V9 to the adsorber 12 with the adsorber 12 to fill the low-pressure buffer tank 18 with gas. enriched with nitrogen. If desired, the low-pressure buffer container 18 through the V9 valve can bring the nitrogen-enriched mixture into the room 2, as exemplified when the container with the adsorbent 12 is in the regeneration cycle, or when temporarily introduced into the atmosphere of the enclosed space 2 in the unit of time. nitrogen-enriched gas must be increased.

[0092] Next, with the schematic representation in Fig. 5, an embodiment of the neutralization device 1 according to the invention is described.

[0093] According to a further embodiment of the invention, it is provided that the enclosed room 2 is provided with a first gas separation system 10 and at least one further gas separation system 10 ', each of which separate the gas separation systems 10, 10' each in the same manner as the separation systems 10 of the gases that are used in the embodiments according to the embodiments of Figures 1 to 4. In particular, both gas separation systems 10, 10 'serve respectively to produce a nitrogen enriched gas mixture at the respective outlet 10b, 10b' of the corresponding separation system 10, 10 ' gases.

[0094] In the embodiment according to Fig. 5, each of the two gas separation systems 10, 10 'has its own compressor system 3, 3', wherein the two compressor systems 3, 3 'are controlled independently of one another. Each compressor system 3, 3 'serves to bring the initial mixture in compressed form to the associated 10, 10' gas separation system. In a suitable gas separation system 10, 10 ', at least part of the oxygen contained in the initial mixture fed is separated. The oxygen separated from the initial mixture is transferred via degassing lines 11, 11 'to the outside atmosphere.

The nitrogen enriched gas mixture, produced at the corresponding exit 10b, 10b 'of the gas separation system 10, 10', is then introduced into the atmosphere of the enclosed space 2, preferably in a regulated manner, especially such that the set and compared to normal ambient air is lowered the oxygen level in the atmosphere of the enclosed room 2 is achieved and maintained.

[0096] As shown in Fig. 5, a gas separation system 10 and at least one further gas separation system 10 'are connected in parallel to one another, the respective input 10b, 10b' being connected or capable of being in fluid communication with a closed room 2. Presented in Fig. 5, the schematic embodiments of the gas separation systems 10, 10 'used are suitably adapted to selectively operate in VPSA mode or in PSA mode.

[0097] Also in the case of the schematic embodiment of the invention shown in Fig. 5, a control device 4 is provided, which is intended to control, if necessary, at least one gas separation system 10, 10 'from the associated separation systems 2, 10, 10 'gases, that the operating mode of the appropriate gas separation system 10, 10' is switched from VPSA mode to PSA mode. This is particularly the case when it is determined that there is insufficient homogeneity in the atmosphere of the closed room 2.

[0098] In other words, when a suitable sensor senses that a gas stratification takes place in a closed space or when it is determined that a confined room atmosphere is not adequately homogeneous in the atmosphere of the closed room 2, the control device 4 sends a signal to at least one of the both gas separation systems 10, 10 'so that it switches to PSA mode. Since, in the PSA mode, an appropriate gas separation system 10, 10 'at the corresponding output 10b, 10b' per unit time, a larger amount of nitrogen enriched mixture is produced, it can be ensured that there is a strong mixing in the atmosphere of the enclosed space 2.

[0099] The invention is not limited to the embodiments shown in the drawing but results from a review of all the features disclosed herein.

[0100] In particular, it is possible that the device has associated with it, preferably independently driven gas separation systems. In this case, the control device 4 is preferably designed such that when gas separation systems fail or for any other reason, one of the gas separation systems can not produce a nitrogen enriched mixture or the amount of nitrogen enriched gas mixture produced per unit of time by gas separation systems , is below the design value for a gas separation system, at least one of the other 10 gas separation systems switch from VPSA mode to PSA mode. Switching from VPSA mode to PSA mode is preferably done automatically as soon as it is determined that the amount of nitrogen enriched gas mixture produced by the gas separation systems per unit of time,

List of markings [0101] Neutralization device enclosed in a room

2a room space

3, 3 'compressor system

3a, 3a 'input of the compressor system

3b, 3b 'compressor system output control device oxygen level measurement device fire detection parameter sensor vacuum source

7a vacuum source input

7b vacuum source outlet blowing fresh air mixing chamber

10, 10 'gas separation system

10a, 10a 'input of the gas separation system

10b, 10b 'output of the gas separation system

11, 11 'degassing lines for the first adsorption container

12a, the first adsorption container 12b entering the first adsorption container the second adsorbent container

13a input of the second adsorbent vessel 13b output of the second adsorbent vessel first heat exchanger system second heat exchanger system first catalyst system second catalyst system negative pressure buffer tank return pipes supply blow out blow

V1 to V9 valves