DE202020105769U1 - Device for cleaning air contaminated with virions - Google Patents

Abstract

Device for reducing the load of enveloped virions in ambient air containing aerosols, comprising a housing (1) and a blower (3) by means of which the ambient air can be conveyed through the housing (1), and a device for providing a cleaning liquid (F) that can be wetted Surface, characterized in that the cleaning liquid (F) contains surfactants, so that when the aerosols containing enveloped virions come into contact with the surface, these virions are deactivated.

Description

introduction

The invention relates to a device for cleaning air and other gases. In particular, the invention relates to a device for cleaning air contaminated with enveloped virions.

State of the art and disadvantages

The harmful effects of viruses on humans are well known. Typical routes of infection are droplet infection, for example through coughing or sneezing; Smear infections due to touching contaminated surfaces or direct contact with infected people; and infection due to aerosols, i.e. polluted breathing air. Depending on the virus, the latter route of infection is responsible for up to 50% of infections. In closed rooms in particular, the risk of infection from aerosols continues to increase. Accordingly, it is desirable to reduce as much as possible indoor exposure to virions, ie viruses located outside the cell, in the air we breathe.

Various solutions are known for this from the prior art.

In the simplest case, intensive ventilation ensures a generous exchange of air. However, this is not possible for all rooms, since not every room has a corresponding access to the outside air. In addition, airing often creates a draft that is quickly perceived as unpleasant. The energy loss at low or even high outside temperatures due to lost heating or cooling energy is disadvantageous.

Devices are known for cleaning (breathing) air by means of aerosol filters, so-called HEPA filters, which filter out aerosols and the virions contained therein, ie hold them back. The HEPA filter is located in an air flow that is set in motion by a fan. If both the sucked-in, polluted air and the expelled, cleaned air remain in the room (circulation), no heating or cooling energy is lost. With sufficient dimensioning, the air can also be exchanged so quickly that the remaining virion load is very low. A disadvantage of this solution, however, is the need for maintenance of the device by cleaning or replacing the HEPA filter, which leads to corresponding costs and downtimes. A further disadvantage lies in the need for the integrity test of such a system, which is required according to applicable rules, after the installation of a new or cleaned filter. This is only possible by specially trained personnel. Such a cleaning device is, for example, from the publication EP 1 600 201 A1 famous.

The treatment of the breathing air by means of ultraviolet light is also used, the virion-reducing effect of which has also been known for a long time. Here, too, air is preferably conveyed through a housing by means of a blower. This is light-tight from the outside, since the UV radiation itself is harmful to health. The disadvantage here is also the need for maintenance due to the limited service life of the UV light source and the not inconsiderable amount of energy required to operate the same. Furthermore, the light sources according to the current state of the art can only be produced as mercury lamps and are therefore contaminated with heavy metals. An example of air disinfection using UV light can be found in printed publications U.S. 5,656,242 . Ozone is also generated here, which is a biocide for microorganisms, but is undesirable in the air we breathe.

Other devices for disinfecting room air use chemical agents such as ethanol, formaldehyde or hydrogen peroxide. Although such substances are effective, they have disadvantages such as a possible risk of explosion, or due to restrictions in the so-called MAK value (maximum workplace concentration), they can only be used to a limited extent or not at all for indoor air circulation, but only for release into the outside air.

Object of the invention and solution

The invention is therefore based on the object of providing a device which avoids the disadvantages of the prior art.

Due to the increasing relevance of the elimination of enveloped virions, also called “viruses” below for the sake of simplicity, the invention is intended to serve in particular for the purification of such viruses.

The invention should be usable for any room, including those without direct access to fresh air.

The energy loss when using the device should be as small as possible.

The device should be able to be operated without interruption and maintenance as far as possible, or necessary maintenance should also be possible by inexperienced personnel.

A health-damaging effect through the operation of the device should be excluded.

The impact on the environment due to the operation of the device should be minimal.

The object is solved by a device according to claim 1. Advantageous embodiments can be found in the dependent claims, the following description and the figures.

description

A description will now be given of an apparatus according to the present invention.

The invention relates to a device for reducing the load of enveloped viruses (more precisely: virions) in ambient air containing aerosols. Such viruses are becoming increasingly relevant, which is why there is a particular interest in eliminating such viruses from the air we breathe. Viruses are known to attach themselves to the smallest liquid particles (aerosols) that are released into the ambient air when infected people breathe out. When inhaling air contaminated with such viruses, an inhaling person can in turn become infected. In closed rooms, and especially in those with poor ventilation, a continuous reduction in the load of enveloped viruses in the aerosols is of great importance.

It should be noted that enveloped viruses or virions are always meant when the abbreviated term “virus” is used below.

The device serves to reduce the load of enveloped viruses in ambient air containing aerosols. It includes a housing and a fan, by means of which the ambient air can be conveyed through the housing. It also includes a device for providing a surface that can be wetted with a cleaning liquid, with the aim of enabling contact between aerosol-containing air on the one hand and cleaning liquid on the other. The invention is characterized in that the cleaning liquid contains surfactants, so that when the aerosols containing enveloped viruses come into contact with the surface, these viruses are inactivated.

To reduce the virus load, the ambient air is conveyed through the housing by the fan. In this housing, it and the contaminated aerosols come into contact with a “cleaning liquid”. This contact results in a reduction in the load of enveloped viruses in the ambient air. It should be noted that the term "cleaning" is to be understood in general terms and does not imply any limitation with regard to the possible removal of the viruses from the aerosols. In this respect, the term "cleaning liquid" only means that the load of enveloped virions in the ambient air is reduced, and this is thus "cleaned".

The reduction is achieved by inactivating the enveloped viruses contained in the aerosols that come into contact with the cleaning liquid. In contrast to the devices known from the prior art, there is therefore no filtering by means of mechanical means, i.e. the viruses are (as far as possible) completely removed from the air, which entails the above-mentioned disadvantages (filter change, costs, downtimes). There is also no disinfection of the air, i.e. no (as far as possible) complete killing of any organisms, including those that are not harmful to health, combined with the environmental pollution associated with disinfection (high energy consumption or harmful disinfectants).

Instead, the viruses contained in the aerosols are simply inactivated, which is possible without mechanical filters, the use of energy-intensive radiation, or chemicals that are harmful to health.

A reduction is also achieved in that the cleaning liquid contains surfactants. Tests have shown that a cleaning liquid containing surfactants can be used to significantly reduce the load of aerosols in the ambient air that are contaminated with enveloped viruses. The lipid-containing virus envelope is destroyed or broken open by the surfactant and the virus is thus inactivated. It should be noted that an inactivated residue of the virion that is no longer infectious can remain in the air flow and/or in the cleaning liquid without health consequences having to be feared.

The proportion of surfactant in the cleaning liquid is typically 0.1% to 99.9%. However, it is preferably in the range of 2% to 70%, and more preferably in the range of 5% to 50%.

The invention thus avoids the disadvantages known from the prior art.

Such a device can be used in particular to reduce the burden of enveloped viruses in the ambient air. It can be used in closed rooms and has a high energy efficiency. It's easy and very inexpensive to maintain, and it won't work Health hazards nor environmental damage from it.

The invention explicitly serves to eliminate enveloped viruses from the air we breathe. In this respect, the invention also acts selectively, in contrast to a particulate filter. The energy loss when using the device is very low, since only a blower and a pump are required for operation. The device can be used without interruption and maintenance-free, as there is no need to replace filters, UV lamps or harmful chemicals. In addition, maintenance can also be carried out by inexperienced personnel. When using the device, there is no harmful effect. Finally, there are no environmentally harmful substances such as contaminated particulate filters or used mercury vapor lamps containing heavy metals.

Various embodiments are described in more detail below.

According to a preferred embodiment, the viral load is reduced by inactivating the enveloped viruses contained in the aerosols that come into contact with the cleaning liquid, and the cleaning liquid contains surfactants. In other words, the inactivation does not take place in any way, but precisely through the use of a surfactant-containing liquid.

In principle, all known surfactants can be used as active ingredients. In particular, the surfactants are as biodegradable as possible and therefore environmentally friendly. The main features here are the lipid-dissolving property for reducing surface tension. The complete wettability of surfaces should also be guaranteed, so that a continuous phase separation layer is created between the liquid and the gas phase. Nonionic as well as anionic or cationic surfactants are suitable here. The cleaning liquid is created by mixing water and surfactant to form a detergent, avoiding foaming.

According to one embodiment, the load is reduced by absorption by the cleaning liquid and removal by the same. In other words, when the aerosols come into contact with the cleaning liquid and in particular with the surfactants contained therein, the aerosols are at least temporarily bound to the cleaning liquid and release the viruses into the cleaning liquid. There they are inactivated and finally transported away by means of the cleaning liquid.

According to another embodiment, the load is reduced by means of interaction in the aerosols and removal by means of the same. In other words, when the cleaning liquid and the aerosol come into contact, the surfactant gets into the aerosol, where it leads to the inactivation of the virus, possibly after the aerosol has been detached from the cleaning liquid. The virus (residues) are then transported away by means of the aerosols. Since these only contain inactive viruses (remnants), they are no longer harmful to health.

According to another embodiment, both mechanisms occur together.

According to a preferred embodiment, the device for providing the surface that can be wetted with the cleaning liquid is a packed column, by means of which an interface of the surfactant film can be provided.

In a packed column, the ambient air to be cleaned enters the housing from below and flows through a packed bed from bottom to top. The cleaning liquid is typically applied to the bed from above and runs through it downwards in countercurrent. This results in wetting of the packed bed; the desired interface is provided on the surfaces of the packing.

Accordingly, the ambient air to be cleaned is guided along a device providing a surfactant film for providing a surface wetted with a cleaning liquid, such as a packed column or comparable surface-enlarging geometries. Packed columns are referred to here for the sake of simplicity, which of course can be replaced by fixed packing or components with a similar effect. The packed column or component with the same effect is designed in such a way that the ambient air has to pass through an interface of the surfactant film. The contact time between the aerosols and the interface is selected in such a way that the surfactant breaks open the lipid envelopes of the enveloped viruses contained in the aerosols, as a result of which these enveloped viruses are inactivated.

In other words, the fan transports a stream of aerosol-laden air along the packed column. This is wetted with cleaning liquid. The surface of the packed column is as large as possible, so that the best possible contact between the aerosol-containing air and the cleaning liquid is made possible. On contact, the surfactant then acts on the virus envelopes and damages them. The viruses (remains) inactivated in this way can be transported away by means of the aerosols, or they go into the cleaning liquid, where they can remain until the liquid is disposed of. Even physical contact with the liquid is harmless at all times, since the virus residues do not pose any danger.

However, the pH content of the cleaning liquid changes gradually, so that this can serve as a measure of the effectiveness of the cleaning liquid. The pH value can be measured using a suitable sensor. The fluid can then be renewed if necessary. This can be accomplished by discarding the liquid, or by adding fresh surfactants. The solution according to the invention is therefore very environmentally friendly and virtually eliminates the risk of maintenance personnel being contaminated.

According to a further embodiment, the ambient air can be humidified by contacting the cleaning liquid in order to reduce the lifespan of viruses in the ambient air. In other words, increasing the humidity inside the device will decrease the viability of the enveloped viruses contained in the aerosols. Accordingly, the pollution of the air treated with the device according to the invention can be further reduced.

Particularly preferably, the purified ambient air conveyed out of the housing and originating in an interior space can also be conveyed back again into, and preferably into, an interior space. According to this, the ambient air flows in a circuit so that its temperature does not change or only changes insignificantly during cleaning. Accordingly, the device according to the invention can be used in a very energy-efficient manner; there is no need to heat up or cool down (air conditioning) colder or warmer outside air. Of course, however, the device can be supplemented or combined with climate-improving devices; in particular the above-mentioned moistening can be included in this.

According to a further embodiment, the device comprises a collection container for collecting the cleaning liquid leaving the device for providing the surface which can be wetted with the cleaning liquid, ie the cleaning liquid trickling down the packed column.

Depending on the pH value, the cleaning liquid can be conveyed from the collection container back to the packed column or disposed of as harmless waste water. It is clear that the volume of the collection container must be dimensioned sufficiently and that an inflow and outflow must be provided in order to be able to add fresh cleaning liquid or fresh surfactant or to be able to dispose of used cleaning liquid.

The cleaning liquid thus flows by gravity along the device for providing a surface wetted with a cleaning liquid and collects in a collection container arranged below the same. Depending on the pH value, it is either returned to the facility or disposed of as harmless waste water.

The flow of the cleaning liquid along the device, which is caused by gravity, is very energy-efficient and also low-noise. A small liquid pump is sufficient to transport the liquid to the top of the device.

The collection container is used to catch the trickling liquid; a pH value sensor can preferably also be arranged here. Reference is made to the above explanations on the pH value.

Since the cleaning liquid is neither infectious nor harmful to the environment, no special safety measures are advantageously required here.

According to a particularly preferred embodiment, the surfactant is biodegradable. In particular, according to Regulation (EC) No. 648/2004 or biodegradable in accordance with the law on the environmental compatibility of detergents and cleaning agents (WRMG). Examples of such a surfactant are simple, particularly preferably liquid, soft soaps (potassium soaps, sodium soaps, etc.) as anionic surfactants.

The advantage of such a biodegradable surfactant lies in particular in the unproblematic disposal of the cleaning liquid, since the viruses (remains) contained in it are also harmless to health. Disposal can, for example, take place in the normal house drain (city sewage).

The invention can also contribute to further reducing the enveloped virus load, which relates to the load of the ambient air surrounding the device. This is achieved by the device drawing in dry air from the environment and discharging humidified air into the environment. In fact, the viability of enveloped viruses in particular is higher in dry air than in humid air, especially during the cold season when windows tend to be closed. The device can thus - independently of the purification of the ambient air actually flowing through it that takes place inside - the pollution of the ambient air, which does not flow through the device at all, also reduce by releasing humidified air into the environment, where it mixes with the "outside" ambient air and humidifies it as well.

character list

• 1 eine schematische Darstellung der Komponenten einer erfindungsgemäßen Vorrichtung;
• 2 ein Flussdiagramm zur Verwendung der erfindungsgemäßen Vorrichtung.

The invention is explained below by way of example with reference to figures. while showing

• 1 a schematic representation of the components of a device according to the invention;
• 2 a flowchart for using the device according to the invention.

In the 1 a schematic representation of the components of a preferred embodiment of the device according to the invention is shown.

On a housing 1, which can be stationary or rollable, an intake grille with a coarse filter 2 and a fan 3 is arranged. Larger particles, insects or the like are held back at this point, and the intake grille 2 also serves to protect against injuries. The ambient air enriched with aerosols containing enveloped viruses (dashed arrow) enters the interior of the housing 1 via a throttle valve 4, by means of which the air exchange rate can be adapted to the volume of the room. A differential pressure sensor 13 monitors this process.

After a deflection, the sucked-in ambient air passes through a packed column 5, the surfaces of which are wetted with a cleaning liquid F containing surfactants. The wetting takes place by means of a pump 10 which brings the cleaning liquid F to the packed column 5 from above via a sprinkler unit 6 . The packed column 5 is designed in such a way that the air flow has to pass the boundary surface of the surfactant film. The contact time resulting from the length of the packed column 5 ensures that the lipid shells of the enveloped viruses contained in the aerosols are broken open by means of the surfactant. All viruses contained in the air flow are thus inactivated.

The ambient air, which has now been cleaned, then flows through a droplet separator 7 to reduce the effects of droplets being carried along. Finally, the ambient air leaves the device through a discharge grille 8 as room air freed from active enveloped viruses.

Cleaning liquid F is located in collection container 9. Optionally, this can be viewed through a window and provided with suitable markings (not shown), so that cleaning liquid F, for example made of biosurfactant and water, can also be easily prepared. A level sensor 15 monitors the correct level. The water can be supplied or topped up by means of a filling valve 11 . The correct concentration of the cleaning liquid F is monitored by a pH sensor 16, which the pump 10 releases.

The pump 10 preferably delivers a preselectable volume of liquid to the end of the packed column 5 at the top in the figure only after a minimum fill level in the collection container 9 has been reached. After passing through the packed column 5 driven by gravity, the cleaning liquid F collects again in the collection container 9. There, the pH sensor 16 can be used to continuously monitor the solution concentration for effectiveness. The cleaning liquid F then circulates again by means of the pump 10.

The air flow is preferably only activated with a delay after a set lead time of the pump 10 . This ensures wetting and thus the production of the interfaces required for the operation of the device. It is also advantageous to position the intake grille 2 in the lower floor area and the outlet grille at a height of approx. 1.6 to 1.8 m. The number of air changes, i.e. the proportion of air that is exchanged or cleaned after one hour, should preferably be around 6 (6 times the total room air is circulated per hour).

If the cleaning liquid F is used up, it can be disposed of in the domestic sewage by means of the drain valve 12, provided that a biodegradable surfactant is used as the surfactant.

To avoid the development of bacteria in a humid environment, the blower 3 can be operated in a maintenance mode after a predefined idle time without the inactivation function (i.e. with the pump 5 stopped), so that the device dries from the inside.

In the 2 a simplified flow chart is shown to illustrate the use of the device according to the invention.

Accordingly, air containing aerosols contaminated by enveloped viruses is first sucked in from the environment and conveyed into the housing. A surface wetted with a cleaning liquid containing surfactants is provided there. Ambient air passed along that surface contacts said surface; there an interaction of the aerosols and the substances contained in them takes place enveloped viruses with the cleaning liquid. Due to the surfactant content, the lipid envelopes of the enveloped viruses are broken open and the viruses are thus inactivated. Finally, the air that has been cleaned in this way, ie that is less contaminated with (active) enveloped viruses, can be conveyed out of the housing. There it mixes with the remaining ambient air and thus also reduces the pollution of ambient air that has not passed through the housing.

Reference List

1

housing

2

Intake grille with coarse filter

3

fan

4

throttle

5

packed column

6

sprinkler unit

7

droplet eliminator

8th

exhaust grille

9

collection container

10

pump

11

filling valve

12

drain valve

13

differential pressure sensor

14

flow rate sensor

15

level sensor

16

pH sensor

f

cleaning fluid

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• EP 1600201 A1 [0005]
• US5656242 [0006]
• WO 648/2004 [0047]

Claims (4)

Device for reducing the load of enveloped virions in ambient air containing aerosols, comprising a housing (1) and a blower (3) by means of which the ambient air can be conveyed through the housing (1), and a device for providing a cleaning liquid (F) that can be wetted Surface, characterized in that the cleaning liquid (F) contains surfactants, so that when the aerosols containing enveloped virions come into contact with the surface, these virions are deactivated. device after claim 1 , wherein the device for providing the surface which can be wetted with the cleaning liquid (F) is a packed column (5) by means of which an interface of the surfactant film can be provided. device after claim 1 or 2 , further comprising a collection container (9) for collecting the cleaning liquid (F) leaving the device for providing the surface that can be wetted with the cleaning liquid (F), from which it can be conveyed again to the packed column (5) depending on the pH value, or can be disposed of as harmless waste water. Device according to one of the preceding claims, wherein the surfactant is biodegradable according to Regulation (EC) No. 648/2004 or according to the WRMG.

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