DE102017218070A1 - Method and device for disinfecting and / or sterilizing a liquid - Google Patents

Abstract

The invention relates to a method for disinfecting or sterilizing a liquid (1), in which bacteria contained in the liquid (1) are inactivated. According to the invention, the liquid (1) or a second liquid (2) is subjected to high pressure and injected by means of a high-pressure injection valve (3) into a container (8) with the liquid to be disinfected or sterilized (1), so that the bacteria by fluid shear and / or inactivated by locally high pulses due to cavitation bubble collapse. In addition, the invention relates to an apparatus for carrying out the method.

Description

The invention relates to a method for disinfecting and / or sterilizing a liquid having the features of the preamble of claim 1. Furthermore, the invention relates to a device for carrying out the method.

State of the art

From the prior art a variety of methods are known, by means of which a liquid can be disinfected or sterilized. Here, a distinction is made between chemical and physical processes.

During chemical disinfection, a disinfectant is added to the liquid. Known disinfectants are chlorine, chlorine dioxide, hydrogen peroxide, silver ions and ozone. However, the addition of such disinfectants is not always desirable because it may affect the taste and / or smell of the liquid. This is particularly relevant when the liquid is drinking water.

In physical disinfection, the liquid is thermally treated, that is heated, or irradiated with UV light. Such methods usually require a lot of time and / or energy. Further, when heating a liquid, there is a risk that someone scalds on use of the liquid at this.

In addition, a cleaning or disinfection of a liquid can be effected by means of filtration or pressurization.

From the DE 10 2015 206 406 A1 exemplifies a method for the sterilization of a bacteria-containing liquid, are produced in the pressure waves whose amplitudes and pressure gradients are so large that the bacteria are inactivated upon exposure to the pressure waves. The pressure waves are for this purpose coupled into a container in which the liquid to be sterilized is added.

Based on the above-mentioned prior art, the present invention has the object to provide a method and a device which allow efficient disinfection and / or sterilization of a liquid as possible without affecting the liquid.

To solve the problem, the method with the features of claim 1 and the device with the features of claim 8 are proposed. Advantageous developments of the invention can be found in the respective subclaims.

Disclosure of the invention

A method is proposed for disinfecting or sterilizing a liquid in which bacteria contained in the liquid are inactivated. According to the invention, the liquid or a second liquid is subjected to high pressure and injected by means of a high-pressure injection valve into a container with the liquid to be disinfected or sterilized, so that the bacteria are inactivated by fluid shear and / or by locally high pulses due to cavitation bubble collapse.

The shear forces are generated as the injected liquid enters the liquid received in the container, as the injected liquid travels at high velocity past the liquid received in the container. The higher the injection pressure, the higher the speeds are achieved. The shear forces introduced into the fluid cause bacteria such as coliforms (E. coli) or Legionella to be destroyed or inactivated.

In order to achieve an optimum disinfecting or sterilizing effect, the injection pressure should be above 1,400 bar, preferably above 1,600 bar, more preferably above 2,000 bar. If the injection pressure is above 2000 bar, exit velocities of 650 m / s or more can be achieved.

The exit velocity of the liquid during injection also depends on the size, shape and / or number of injection holes of the high pressure injector used for injection. Injectors which allow high exit velocities are known, for example, from fuel injection technology, so that this technique can be used.

The desired disinfecting or sterilizing effect is preferably not achieved by fluid shear alone. Because - depending on the injection pressure - may occur during injection into the liquid to be disinfected or sterilized local vacuum areas, so that gas bubbles form. These implode as soon as the pressure rises again, whereby large forces are released. This effect, which is usually undesirable, is called cavitation. By cavitation or by the thereby free high forces can thus also be achieved destruction or inactivation of bacteria. To utilize this additional effect, the injection pressure should be above 400 bar, preferably above 800 bar, more preferably above 1000 bar.

The method according to the invention can be used for the disinfection or sterilization of water, In particular drinking water, are used, as this neither the taste nor the smell of the water are affected. For example, in this way water stored in water pipes and / or water storage can be protected against Legionella infestation. In known methods, the drinking water present in the pipe system is heated to over 70 ° C. at regular intervals. If the heated water is then removed from the line, there is a risk of scalding. When using the method according to the invention, this danger does not exist.

If only one liquid is used in the proposed method for disinfecting or sterilizing a liquid, that is to say that the liquid to be disinfected or sterilized itself is injected, then no dilution of the liquid to be disinfected or sterilized takes place. Unless the addition of certain additives is explicitly desired. In this case, the addition may also be by way of high pressure injection, as shown below.

According to a preferred embodiment of the invention, it is proposed that in the method a needle valve is used as a high-pressure injection valve. The injection is controlled in this case via the stroke of a valve needle, the control is very precise. Since most fuel injection valves are designed as needle valves, existing components can be used. The method can thus be implemented relatively inexpensively.

In the case of the invention, a fuel injection valve is preferably used for diesel direct injection, since injection pressures of more than 2000 bar are regularly achieved in this case. Alternatively, the high-pressure injection valve used in the method may be analogous to such a fuel injection valve.

In addition, a gasoline injector can be used, which allows pressures up to about 450 bar. Even with such small pressures bacteria can already be inactivated, so that a disinfecting effect is achieved.

In the method according to the invention, the liquid to be injected is preferably subjected to high pressure before injection by means of a high-pressure pump. In the present case, pressures of more than 400 bar, preferably more than 800 bar, and more preferably more than 1200 bar are referred to as high pressure. Ideally, in the proposed method pressures above 2000 bar are achieved in order to achieve an optimum disinfecting or sterilizing effect. Preferably, a piston pump is used as a high-pressure pump, since such high-pressure pumps are also known from fuel injection technology and thus available.

The pressure data can also be given in the unit Pascal (Pa), where 1 bar = 100,000 Pa = 0.1 MPa. 400 bar corresponds to 40 MPa.

Furthermore, in the method according to the invention, the liquid to be disinfected or sterilized is preferably fed to the container via the high-pressure injection valve and / or via a separate inlet. If the supply takes place solely via the high-pressure injection valve, the amount to be disinfected or sterilized is first subjected to high pressure itself, whereby a part of the bacteria is already inactivated. During injection and penetration into the liquid already present in the container, further bacteria are destroyed by the shearing forces occurring at that time and / or locally high pulses due to cavitation bubble collapse. Over the residence time of the liquid in the container, a further inactivation of the bacteria is achieved by the subsequent injections and the shearing forces or cavitation introduced thereby.

Furthermore, only a part of the amount of liquid to be disinfected or sterilized can be introduced into the container via the high-pressure injection valve. For this purpose, a partial amount is preferably branched off from the inlet and fed to the high-pressure injection valve. The remaining amount passes through the inlet into the container.

Moreover, it is possible that the entire liquid to be disinfected or sterilized is supplied to the container via the inlet and for the injection of a different, second liquid is used.

Ideally, the container is completely filled with the liquid to be disinfected or sterilized so that it is injected directly into the liquid. This means that the liquid jet emitted via the high-pressure injection valve directly penetrates into the liquid without having to pierce further boundary layers. Alternatively or additionally, it is proposed that the high-pressure injection valve is immersed during injection into the liquid to be disinfected or sterilized.

The delivery of the liquid jet by means of the high-pressure injection valve can be continuous or pulsed. Preferably, a pulsed method is used, as this facilitates the vote and the use of relatively small components to provide the required Pressure and / or flow rate allows. The pulsed method thus has the advantage that - with largely the same disinfection or sterilization effect - the energy requirement is significantly lower.

In a further development of the invention, it is proposed that at least one additive in the form of a further liquid, a gas and / or a solid be added to the liquid prior to injection into the liquid received in the container. This additive can be a disinfectant such as chlorine or ozone, if necessary to increase the degree of disinfection or sterilization.

Advantageously, the at least one additive is added by means of an adapter which is arranged on the high-pressure injection valve in the region of a nozzle. In this case, the liquid exiting the nozzle during injection breaks the additive so that a uniform distribution of the additive in the liquid to be disinfected or sterilized is ensured. Furthermore, no separate fitting for the addition of the additive is needed.

The additionally proposed device for carrying out the method according to the invention comprises a container in which a liquid to be disinfected or sterilized is received, and a high-pressure injection valve, by means of which the liquid or a second liquid can be injected under high pressure into the liquid received in the container. By means of the high-pressure injection, shear forces can be introduced into the liquid present in the container, which leads to destruction or inactivation of bacteria. Furthermore, due to cavitation, high pressure pulses may occur which also contribute to the disinfection or sterilization of the liquid.

The high-pressure injection valve is preferably designed as a needle valve. Further preferably, it is designed analogous to a fuel injection valve, in particular analogous to a fuel injection valve for diesel direct injection, since these valves allow high injection pressures and thus high exit velocities.

It is also proposed that the device comprises a high-pressure pump, by means of which the liquid to be injected can be acted upon by high pressure. Only the injection under high pressure leads to the desired disinfection or sterilization effect. The high-pressure pump is preferably designed as a piston pump. For example, a high-pressure fuel pump can be used as a high-pressure pump, which is usually designed as a piston pump, or the high-pressure pump can be constructed analogously to a high-pressure fuel pump. High-pressure fuel pumps allow system pressures of more than 2000 bar.

In a development of the invention, it is proposed that the high-pressure injection valve have an adapter in the region of a nozzle, by means of which at least one additive in the form of a further liquid, a gas and / or a solid can be dispensed. By adding an additive, the disinfection or sterilization effect can be increased if necessary, the addition of which ensures an even distribution by means of an adapter arranged on the high-pressure injection valve, since the liquid emerging from the nozzle entrains the additive.

With the aid of the method according to the invention or with the aid of the device according to the invention, even larger amounts of a liquid can be disinfected or sterilized in a short time. The proportion of the introduced liquid is significantly smaller than that of the liquid to be disinfected or sterilized.

In order to achieve a particularly efficient disinfection or sterilization of even larger quantities of liquid, high-pressure injection valves can be used, which have a multi-hole nozzle geometry. In this way, larger amounts of liquid can be injected and / or distributed better.

Furthermore, the injection can take place in a flowing liquid, so that an already disinfected or sterilized amount is removed faster. In this way, the volume of sales can be further increased. The container is to be provided for this purpose with an inlet and a drain.

The container can therefore be both a tank with a defined volume and a pipe or pipe section through which the liquid to be disinfected or sterilized flows.

• 1 eine schematische Darstellung einer erfindungsgemäßen Vorrichtung gemäß einer ersten bevorzugten Ausführungsform,
• 2 eine schematische Darstellung einer erfindungsgemäßen Vorrichtung gemäß einer zweiten bevorzugten Ausführungsform,
• 3 eine schematische Darstellung einer erfindungsgemäßen Vorrichtung gemäß einer dritten bevorzugten Ausführungsform,
• 4 eine schematische Darstellung einer erfindungsgemäßen Vorrichtung gemäß einer vierten bevorzugten Ausführungsform und
• 5 eine schematische Darstellung einer erfindungsgemäßen Vorrichtung gemäß einer fünften bevorzugten Ausführungsform.

The invention will be explained in more detail with reference to the accompanying drawings. These show:

• 1 a schematic representation of a device according to the invention according to a first preferred embodiment,
• 2 a schematic representation of a device according to the invention according to a second preferred embodiment,
• 3 a schematic representation of a device according to the invention according to a third preferred embodiment,
• 4 a schematic representation of a device according to the invention according to a fourth preferred embodiment and
• 5 a schematic representation of a device according to the invention according to a fifth preferred embodiment.

Detailed description of the drawings

Of the 1 is a device for disinfecting and / or sterilizing a liquid 1 to take out a container 8th and one on the container 8th arranged high-pressure injection valve 3 includes. The high-pressure injection valve 3 is designed as a needle valve. That is, the high pressure injector 3 a liftable valve needle 14 has, via the lifting movement of the injection is controllable. The valve needle 14 acts with a nozzle 6 together, in the at least one injection opening 15 and one of the injection port 15 upstream valve seat 16 is trained.

The in the 1 The illustrated device further comprises a high-pressure pump 7 that have an inlet 9 with the liquid 1 is available. The high pressure pump 7 acts on the liquid 1 with high pressure and leads them to the high-pressure injection valve 3 to. In a pulsed process, the high-pressure liquid 1 by means of the high-pressure injection valve 3 in the container 8th injected, with the liquid 1 deep into the already in the container 8th existing liquid 1 penetrates. Shear forces are generated which lead to the desired disinfection or sterilization effect. The thus disinfected or sterilized liquid 1 is then via an output 10 from the container 8th dissipated.

Of the 2 is another device for disinfecting and / or sterilizing a liquid 1 refer to. Here is the liquid to be disinfected or sterilized 1 in the container 8th or is via an inlet 9 the container 8th fed. The feed 9 has a branch 11 on, to the high pressure pump 7 leads. About the branch 11 becomes a subset of the liquid to be disinfected or sterilized 1 branched off, subjected to high pressure and by means of the high-pressure injection valve 3 in the container 8th existing liquid 1 injected. Instead of the liquid 1 could also be a second liquid 2 (see reference numerals in parentheses) in the liquid 1 be injected. The branch 11 would not exist then, but would - analogous to 1 - By another inlet to the high pressure pump 7 replaced.

In the 3 is another associated with the high-pressure injection effect, which leads to a disinfecting or sterilizing effect. When injecting form along a jet of liquid 13 cavitational 12 in which there is a negative pressure, so that there is the formation of gas bubbles. These implode as soon as the pressure rises again and trigger a high pressure pulse.

In the 4 is a high pressure injector 3 with a multi-hole nozzle 6 shown. Over this are several liquid jets 13 deliverable, so that with an injection larger amounts of liquid can be disinfected or sterilized.

In the embodiment of the 5 has the high pressure injector 3 in addition an adapter 5 on the outside in front of the nozzle 6 is set, so that the liquid 1 respectively. 2 over the adapter 5 exit. In the adapter 5 there is an addition 4 , For example, a disinfectant, the leakage of the liquid 1 . 2 being carried away. About the adapter 5 can thus liquid, gaseous or solid additives 4 be added.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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.

Cited patent literature

• DE 102015206406 A1 [0006]

Claims (11)

Method for disinfecting or sterilizing a liquid (1) in which bacteria contained in the liquid (1) are inactivated, characterized in that the liquid (1) or a second liquid (2) is pressurized and pressurized by means of a high-pressure injection valve (3 ) is injected into a container (8) with the liquid (1) to be disinfected or sterilized so that the bacteria are inactivated by fluid shear and / or by locally high pulses due to cavitation bubble collapse. Method according to Claim 1 , characterized in that a needle valve is used as a high-pressure injection valve (3). Method according to Claim 1 or 2 , characterized in that the liquid to be injected (1, 2) before injection by means of a high-pressure pump (7) is subjected to high pressure, with pressures above 400 bar, preferably over 800 bar, further preferably over 1200 bar can be achieved. Method according to Claim 3 , characterized in that a piston pump is used as a high-pressure pump (7). Method according to one of the preceding claims, characterized in that the liquid to be disinfected or sterilized (1) via the high-pressure injection valve (3) and / or via a separate inlet (9) is supplied to the container (8). Method according to one of the preceding claims, characterized in that the container (8) is completely filled with the liquid to be disinfected or sterilized (1) and / or the high-pressure injection valve (3) immersed in the liquid to be disinfected or sterilized (1) becomes. Method according to one of the preceding claims, characterized in that the liquid (1, 2) prior to injection into the liquid (1) received in the container (8) at least one additive (4) in the form of another liquid, a gas and / or a solid is added. Method according to Claim 7 , characterized in that the at least one additive (4) by means of an adapter (5) is added, which is arranged on the high-pressure injection valve (3) in the region of a nozzle (6). Apparatus for carrying out the method according to one of the preceding claims, comprising a container (8) in which a liquid (1) to be disinfected or sterilized is received, and a high-pressure injection valve (3), by means of which the liquid (1) or a second Liquid (2) under high pressure in the container (8) recorded liquid (1) can be injected, wherein preferably the high-pressure injection valve (3) is designed as a needle valve. Device after Claim 9 , characterized in that the device further comprises a high pressure pump (7) by means of which the liquid to be injected (1, 2) can be acted upon by high pressure, wherein preferably the high pressure pump is designed as a piston pump. Device after Claim 9 or 10 , characterized in that the high-pressure injection valve (3) in the region of a nozzle (6) has an adapter (5), by means of which the liquid to be injected (1, 2) at least one additive (4) in the form of another liquid, a gas and / or a solid is zugebbar.

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