WO1998035759A1

WO1998035759A1 - Device for admixing additives and method for cleaning and/or disinfecting therewith

Info

Publication number: WO1998035759A1
Application number: PCT/EP1998/000658
Authority: WO
Inventors: Werner Lüdecke; Thomas Tyborski; Dimitri Ouzounis; Heinz Goerke
Original assignee: Henkel-Ecolab Gmbh & Co. Ohg
Priority date: 1997-02-15
Filing date: 1998-02-06
Publication date: 1998-08-20
Also published as: DE19705861A1

Abstract

The invention relates to a device for dosable admixing of an additive (A) via a solution flowing from a feed pipe (6) into a main pipe (1), comprising an injector (3), whose suction opening (4) is connected to the feed pipe (6), as well as a through-flow regulating valve (8) arranged in the feed pipe (6). The injector (3) has at least two suction openings (4, 5) placed in the direction of solution flow (10) at a same height. The second suction opening (5) is connected to a second feed pipe (7) for a second additive (B). The additive concentrations can be independently adjusted over a wide range.

Description

Device for admixing additives and method for cleaning and / or disinfecting carried out therewith

The device relates to a device for metering admixture of an additive via a feed line to a solvent flowing in a main line, in particular water, with an injector arranged in the main line, the suction opening of which is connected to the feed line, and with a flow control valve arranged in the feed line.

For cleaning and / or disinfecting solid surfaces, e.g. B. tiled walls, floors, large containers and food processing plants are used in many areas devices that spray a cleaning or disinfectant solution with different levels of pressure without foam or in the form of foam. A distinction is made between the so-called low-pressure devices working at pressures below 25 bar and the high-pressure devices working at pressures of 25 bar and more. The devices are used, for example, in production areas of the food manufacturing and processing industry and in the technical or industrial area, e.g. B. in workshops, especially for cleaning cars and trucks. The device according to the invention is intended for use in particular in the food manufacturing and processing industry, in which particularly high demands are placed on cleaning and disinfection.

Typical devices used in this area have an injector with only one suction opening, through which only a single cleaning agent or disinfectant is added to the water flowing in the main line. In such injectors known per se for metering chemicals, the chemical is sucked in according to the Venturi principle by the negative pressure which arises at the point of the injector when the water flows. With a flow control valve in the concentrate suction line, which is also called the feed line here, the application concentration of the product used can be freely selected.

In the case of low-pressure foam devices, it is also known to produce a cleaning or disinfecting foam by supplying compressed air to an application solution prepared in this way. With these devices, the simultaneous use of two concentrates is not possible. However, it can be advantageous for certain applications to use two different products at the same time, e.g. B. use a detergent and a cleaning booster at the same time. What is desired is a freely selectable setting of the respective concentration for both products that is tailored to practical conditions. A change in the concentration setting for one product should also not affect the concentration of the other product.

A separate metering in of concentrates is particularly essential if premixing of the product concentrates and metering via only one suction opening of the injector is not possible. The combination of an alkaline cleaning agent and a cleaning booster or disinfectant based on hydrogen peroxide may be mentioned as an example. Both components react violently with each other in concentrated form, releasing free oxygen, the cleaning or disinfecting effect of which, however, is only to be developed on the soiled surface. However, the concentrations of both components in the ready-to-use solution are so low that the undesired premature decomposition of the peroxide is largely avoided.

Also known are cleaning devices with several injectors, each with a suction opening, via which several components can be added to the cleaning medium at the same time. Thus, the high-pressure cleaning device known from DE 33 10 663 C2 shows a high-pressure line for water that is divided into two branch lines. An injector is provided in each branch line, which can be used to draw in a liquid chemical on the one hand and an air-powder mixture on the other hand. The amount of powder sucked in can be adjusted via a continuously adjustable conveying device for the powder. After the additives have been added by means of the injectors built into the branch lines, the branch lines combine and the application solution is sprayed through a nozzle after passing through a mixing section.

If the dosing of liquid additives is carried out according to this principle, the concentrations of the additives in the working solution fluctuate to an extent that is no longer acceptable for many applications, as the inventors have have found. The cause is suspected in flow turbulence in the main line, so that there is no constant time division into two partial flows.

The invention is therefore based on the object of metering in at least two liquid additives into the main line in a freely selectable, mutually independent and practice-oriented concentration setting using a device of the type mentioned. A desired change in the concentration of one additive should not influence the concentration of the other additive. In addition, the constancy over time of the once set concentration ratio of the additives is required, irrespective of temporal fluctuations in the pressure of the main line. In particular, additives should also be metered in, in which the mixture in a concentrated form is not desired.

This object is achieved in that the injector has at least two suction openings which are at the same height in the direction of the flow of the solvent, and that the second suction opening is connected to a second feed line for a second additive.

The device according to the invention is preferably designed for a liquid solvent and for liquid additives.

The common entry point for the additives in the main line leads to several technical advantages. On the one hand, pressure fluctuations in the main line have the same effect on all injectors, so that the ratio of the flow rates of the additives and thus the ratio of the concentrations in the working solution are largely independent of the water pressure. A change in the setting of one flow control valve also has no effect on the metering rate of the other additives, since their suction openings are exposed to the full, unchanged pressure in the main line.

Another important advantage is the possibility of metering in additives which are immiscible with one another in concentrated form, since each injector opens directly into the main line, so that the additives can only come into contact with one another in dilute form. The injector preferably has intake ports which are oriented at an angle of 90 ° to the direction of flow of the solvent. For structural and spatial reasons, it is advantageous if the injector has intake manifolds which form an angle of 90 to 180 ° with one another.

The flow rates for all additives and thus the concentrations in the ready-to-use solution should preferably be adjustable separately. It is therefore proposed that a flow control valve, for. B. a needle valve is provided.

In particular, the device according to the invention is used to produce cleaning or disinfecting foam. For this purpose, an air supply line, which is connected to the main line and is arranged downstream of the injector in the flow direction, is provided for producing foam in a further preferred embodiment.

The invention also relates to a method for cleaning and / or disinfecting, in particular of solid surfaces, with a device according to the invention already mentioned, which is connected to a pressurized water pipe. This water pipe can be the water pipe network or a water reservoir with a booster pump.

For this process, the inventors propose that at least two additives which chemically react with one another in the undiluted state are added to the water flowing in the main line, one of which is a cleaning agent and the other of which is a cleaning booster and / or a disinfectant.

In the process according to the invention, combinations of additives which were not previously usable can be used in the working solution to be sprayed on. As a result, considerably improved cleaning and disinfection effects can be achieved, which were previously not achievable due to the chemical reaction of the concentrated additives with one another and the premixing of the concentrates which was therefore not possible.

Preferably the one additive is an alkaline detergent and the other additive contains peroxide. Hydrogen peroxide and peracetic acid may be mentioned as examples of such peroxides which give off free oxygen in contact with alkalis. As further combinations of additives in a concentrated form are not miscible with each other, but which lead to a significantly improved cleaning and disinfection effect, the following are mentioned:

H2O2 or peracetic acid / H2θ2 + foam component alkaline component + foam component acidic component + foam component alkaline / surfactant-containing K. + H2O2 or peracetic acid / H2θ2 acidic / surfactant-containing K. + H2O2 or peracetic acid / H2θ2 neutral / surfactant-containing K. + H2O2 or peracetic acid / H2θ2 lipophilic component + lipophobic component alkaline component ^• + thickening, e.g. B. gel-forming K. acidic component + thickening, e.g. B. gel-forming K. neutral component + thickening, z. B. gel-forming K.

The method according to the invention can be operated with a water pressure of less than 25 bar in the main line, ie with "low pressure", or with a water pressure of at least 25 bar in the main line, ie with "high pressure". Foam cleaning is preferably carried out in the low pressure range. Of the many application advantages compared to high-pressure cleaning, the low aerosol formation, the greater occupational safety for the cleaning staff and the better protection of the surfaces, machines and systems are examples. High-pressure cleaning can only be used if the surfaces, machines and systems withstand this high mechanical stress.

An exemplary embodiment of the invention and comparative examples are explained in more detail below with reference to drawings. Show it

FIG. 1 shows a flow diagram of an exemplary embodiment according to the invention,

FIG. 1 a shows a detail from FIG. 1,

FIG. 2 shows the change in concentration over time with different settings of the device according to FIG. 1 in a diagram,

FIG. 3 shows a diagram corresponding to FIG. 2, which shows the results of a second experiment, FIG. 4 shows an illustration according to FIG. 2 with respect to a third experiment with the device according to FIG. 1,

Figure 5 is a flow chart corresponding to Figure 1 for a device according to the

State of the art,

FIG. 6 shows a flow diagram corresponding to FIG. 5, which shows the arrangement with respect to a first comparative example,

FIG. 7 shows a representation according to FIG. 6 with respect to a second comparative example and

Figure 8 is an illustration of Figure 6 with respect to a third comparative example.

In all drawings, the same reference symbols have the same meaning and are therefore only explained once, if appropriate.

In the exemplary embodiment according to the invention according to FIG. 1, a main line 1, namely a pressure pipe, is connected to the water supply network. The flow can be adjusted with a control valve 2.

An injector 3 built into the main line 1, which is shown in an enlarged schematic illustration in FIG. 1a, enables two additives A and B to be metered in. The additives A, B are added via the intake ports 4, 5 and the supply lines 6, 7 connected to them sucked out of their storage containers, not shown. For example, additive A can be an alkaline cleaning agent concentrate and additive B can be concentrated hydrogen peroxide.

The flow control valves 8, 9 built into the flow lines 6 and 7 allow the concentrations of the additives A, B in the application solution to be set separately. As is evident from FIG. The intake manifold 6, 7 lie opposite each other in this embodiment, so that they form an angle of 180 ° with one another. In the flow diagram according to FIG. 1, an entry point 11 for compressed air is provided downstream behind the injector 3. The amount of compressed air can be adjusted via a further control valve 12, and the pressure in this branch line is displayed by a measuring device 13. The foam emerging from a nozzle (not shown) at the end of the main line is used for cleaning and disinfecting solid surfaces and large containers.

Experiments were carried out with the device according to FIG. 1 which show the desired independence of one concentration setting from the other. For the sake of simplicity, water with a temperature of 15 ° C. was used as additive A and additive B. The main line 1 was supplied with water of 25 bar and a flow rate of 9.62 l / min. The main line 1 consisted of a hose 20 m long and an inner diameter of 12 mm. The air entering at the entry point 11 had a pressure of 6 bar.

The results can be found in Tables 1 to 3 below. The setting was changed by means of the flow regulators 8, 9 which contained needle valves.

Table 1: Setting equal concentrations of additives A and B

Component A component € - B

No. Setting flow rate concentration A flow rate concentration

1 0/4 110 1, 1 0/4 100 1, 0

2 0/8 330 3.3 0/8 320 3.2

3 1/1 490 4.8 1/1 490 4.8

4 1/5 630 6.1 1/5 630 6.1

5 1/9 740 7.1 1/9 740 7.1

6 2/2 840 8.0 2/2 840 8.0

Table 2: Setting with half the concentration of additive B

Component A Component B

No. Setting flow concentration setting Flow concentration concentration

1 0/4 120 1, 2 0/2 20 0.2

2 0/8 330 3.3 0.4 100 1.0

3 1/1 500 4.9 0/6 230 2.3

4 1/5 640 6.2 0/8 320 3.2

5 1/9 760 7.3 0/10 380 3.8

6 2/2 880 8.4 1/1 440 4.4

Table 3: Setting constant concentration of additive B at different concentrations of additive A

Component A Component B

No. Setting the flow concentration Setting the flow concentration

1 0/4 120 1, 2 0/4 110 1, 1

2 0/8 320 3.2 0.4 110 1, 1

3 1/1 510 5.0 0/4 110 1, 1

4 1/5 640 6.2 0/4 110 1, 1

5 1/9 760 7.3 0/4 110 1, 1

6 2/2 880 8.4 0/4 110 1, 1

In the second and fifth columns, the setting of the needle valves 8, 9 is given, the first number indicating the number of revolutions and the second number indicating the setting on an arbitrary scale that is the same for both valves. The third and sixth columns list the flow rates in the feed lines 6, 7, which were measured in ml / min. The resulting concentrations of components A and B can be found in the fourth and seventh columns. They were calculated as% by volume from the flow rates in the feed lines 6, 7 and the flow rate in the main line 1.

The results of Tables 1 to 3 are shown graphically in FIGS. 2 to 4, the concentration in vol.% For both additives A and B being plotted against the test number.

Table 1 and Figure 2 show that the desired concentrations can be set within a wide range without problems.

A comparison of the results in Table 2 and Table 1 shows only very slight deviations in the concentration of component A with the same setting of valve 8 if valve 9 for component B is set to half the value. The concentrations assigned to the valve settings can therefore be reproduced very well regardless of the setting of the other valve. The extremely slight or practically non-existent mutual influence of the valve settings can be seen in particular in Table 3 and Figure 4. Here, a very low scale position of valve 9 was selected for component B and kept constant during the tests. Despite the large change in the flow through the feed line 6 corresponding to a change in concentration of 1.2 to 8.4%, the flow in the other feed line 7 did not change.

For comparison with the embodiment according to the invention, FIG. 5 shows a flow diagram of the prior art already mentioned above. Only a single additive A can be metered in here, as can be seen from the comparison of FIG. 5 and FIG. 1.

FIGS. 6 to 8 show flow diagrams of arrangements with which comparative tests were carried out.

No reproducible settings could be achieved with any of these systems. The reason lies in unfavorable flow and pressure conditions. As a result, component A and / or component B were sucked in unevenly. In the system according to FIG. 6, the flow and pressure conditions were so unfavorable that either only component A or only component B was sucked in. In addition, interactions occurred, which was expressed by the fact that when the concentration of component A was changed, a change also occurred in component B and vice versa.

Reference list

A additive

B additive

1 main line

2 control valve

3 injector

4 intake manifolds

5 intake manifolds

6 supply line

7 supply line

8 flow control valve

9 flow control valve

10 flow

11 entry point

12 control valve

13 pressure display

Claims

claims

1. Device for the metered admixture of an additive (A) via a feed line (6) to a solvent flowing in a main line (1), in particular water, with an injector (3) arranged in the main line (1), the suction opening (4) of which is connected to the feed line (6), and to a flow control valve (8) arranged in the feed line (6), characterized in that the injector (3) has at least two suction openings (4, 5) which point in the direction of the flow (10 ) of the solvent are at the same level, and that the second suction opening (5) is connected to a second feed line (7) for a second additive (B).

2. Device according to the preceding claim, characterized in that the device is designed for a liquid solvent and for liquid additives (A, B).

3. Device according to one of the preceding claims, characterized in that the injector has intake ports (4, 5) which are oriented at an angle of 90 ° to the direction of flow of the solvent.

4. Device according to one of the preceding claims, characterized in that the injector has intake manifolds (4, 5) which form an angle of 90 to 180 ° with one another.

5. Device according to one of the preceding claims, characterized in that in each feed line (6, 7) for the additives (A, B) a flow control valve (8, 9) is provided.

6. Device according to one of the preceding claims, characterized by an air supply line connected to the main line (1) and arranged downstream of the injector (3) to produce foam.

7. A method for cleaning and / or disinfecting, in particular of solid surfaces, with a device connected to a pressurized water line according to one of the preceding claims, characterized in that at least two additives (A, B) which chemically react with one another in the undiluted state. to the water flowing in the main line (1), the one additive (A) being a cleaning agent and the other additive (B) being a cleaning booster and / or a disinfectant.

8. The method according to the preceding claim, characterized in that the one additive (A) is an alkaline cleaning agent and the other additive (B) contains peroxide.

9. The method according to claim 7 or 8, characterized in that one works with a water pressure of less than 25 bar in the main line (1).