DE10033339A1 - Process and plant for cleaning and / or disinfecting hard surfaces with a foam - Google Patents

Abstract

In the method for cleaning and/or disinfecting hard surfaces with an aqueous foam, comprising cleaning and/or disinfecting agents, the foam is generated by means of mixing water, air and a concentrated cleaning and/or disinfecting agent in a mixer unit (1). The concentration of the cleaning and/or disinfecting agent in said foam, based on water used, is recorded and/or monitored. The use of concentrated cleaning and/or disinfecting agent per unit time is continuously measured and the concentration of the cleaning and /or disinfecting agent in the foam is determined therefrom and from the use of water per unit time. A continuous, simple, rapid and error-free determination and monitoring of the concentration of the cleaning and/or disinfecting agent in the cleaning and/or disinfecting foam is thus possible.

Description

The invention relates to a method for cleaning and / or disinfecting hard surfaces with an aqueous, cleaning and / or disinfecting medium-containing foam, the foam being obtained by mixing water, Air and a concentrated cleaning and / or disinfectant in one Mixing unit is generated and the concentration of the cleaning and / or Disinfectant in this foam, based on the water used, recorded and / or monitored.

For cleaning and / or disinfecting solid surfaces, e.g. B. with tiles provided walls, floors, large containers and food processing systems are used in many areas that require a cleaning or disinfectant solution with different pressure foamless or spray in the form of foam. The pressures are below 25 bar working so-called low pressure devices and those at pressures of 25 bar and more working high pressure equipment. The are applied Devices, for example, in food production areas and manufacturing industry and in the technical or industrial field, e.g. B. in workshops, especially for cleaning passenger and truck vehicles. The invention is for use in particular in the food manufacturing and manufacturing industry provided in the particularly high requirements cleaning and disinfection.

Systems used in practice for cleaning hard surfaces using Foams work in the following way: On the one hand, a water stream becomes air and on the other hand surfactant-containing cleaning components or disinfectant components  fed in concentrated form. The resulting foam with a hose over a foam nozzle to the to be cleaned or disinfectant surface applied.

The concentrated cleaning agent or disinfectant is metered in according to the Venturi principle. This principle uses the pressure difference in flowing media, which, for example, by introducing a throttle point. B. is generated in a pipeline. The throttling point usually consists of a cross-sectional constriction in the form of a nozzle. The resulting negative pressure is used in the foam cleaning systems to suck in the cleaning agents and disinfectants. This known mode of operation is shown in FIG. 2.

For monitoring the concentration of the reini known in the prior art agent or disinfectant in the foam, based on the used Water, the concentration is determined by titration or the concentration is by means of reducing nozzles and / or needle valves on the suction line for the Concentrate set.

However, these known methods of monitoring concentration have following disadvantages.

The adjustment of the concentration by means of valves or reducing nozzles on the Foam systems are not precise enough, depending on the air and water pressure as well as strong fluctuations in the concentrations depending on the flow conditions tration occur. Also the viscosity of the cleaning or desin to be dosed fection agent and the temperature of the water have an essential Influence on the actual concentration at a certain setting of the Valves or the reducing nozzles. Have tried in practice confirms that the use of reducing nozzles in the intake lines for the Concentrate no reproducible and transferable when changing products Provides results regarding the desired concentration in the foam.

Therefore, when using reducing nozzles or valves (needle valves) it can be too Underdoses or overdoses come with the result that insufficient or cleaning and / or disinfection results that cannot be reproduced or a  for the use of excessive consumption of cleaning agents or disinfectants means are obtained.

Finally, the cross section of the reducing nozzles, e.g. B. by Verunreini conditions or crystallization of the cleaning agent / disinfectant, ver smaller. The result is too low a concentration. It may Not noticed at all or only too late so that poor cleaning results will be obtained, which will disrupt the operation can lead hygiene. Especially in the field of food processing Industry, this is a significant disadvantage.

But the well-known titration for determining the concentration also shows one A number of major disadvantages. In practice, the foam is in one Containers, e.g. B. caught a bucket. First, the foam must be in liquid be disintegrated in order to carry a sufficient amount of liquid to carry out Titration available. This requirement depends on the stability of the Foam very time consuming. With a new adjustment, a calibration of the Foam system, a product change, product monitoring, etc. therefore the operator lost valuable time in this way. This applies in particular if the personnel carry out the titration from Detergent manufacturer is provided because to carry out the Titration sufficient experience and previous knowledge is required.

Titrations of neutral solutions, e.g. B. certain disinfectants based on QAV (Quaternary ammonium compounds) based, or containing anionic surfactants Cleaning agents are prone to errors, time-consuming and sometimes not possible. So can the two- according to DIN ISO 2871-1 + 2 and DIN ISO 2271 Phase titration for surfactant determination using chloroform Users are usually not carried out. The reason for this is that Chloroform has a narcotic effect on inhalation and oral ingestion, in larger ones Amounts of paralyzing and chronic effects - how many Chlorinated hydrocarbons liver damage. Chloroform is now considered a substance reasonable suspicion of carcinogenic potential (category IIIb of the carcinogenic agents). Quotation: Römpps Chemie Lexikon, Prof. Dr. J. Jalbe, Prof. Dr. M. Regitz, Stuttgard, New York, 9th, expanded and revised Edition, 1989-1992, page 707.  

If, in these cases, the detergent or Disinfectant is the result, it can - as with others from a standing start the technology known monitoring methods - to microbiological pro come blemen.

The user, namely the food processing company, is in some Cases overwhelmed with the titration procedure, e.g. B. if a two-phase titration is required. Therefore, the concentrations are often not correctly determined and / or not properly controlled. Especially with foam disinfectants in this case there is an increased risk of accidents with a QAV content. So In practice it turned out that the concentration actually used of the disinfectant 10 times the size of the recommended application was concentration.

After all, there can be high deviations from the actual concentrations. Before the titration, the wait for complete disintegration of the foam. However, since wait for this times of up to 1 hour have to be accepted, is the foam do not completely disintegrate in practice before sampling. On the other hand If the surfactants accumulate in the foam, the results of the titration are incorrect. Another source of error arises when pipetting, because there may be more Foam in the pipette leads to incorrect titration results.

A special process variant for foam cleaning is the so-called called double injector system to achieve. This method is e.g. B. in the German patent application DE 197 05 861 A1 (Henkel-Ecolab GmbH & Co. OHG) described. Here two become immiscible in the concentrate Cleaning components of the water flow using the Venturi principle fed. This significantly improves cleaning performance.

An example is a mixture of alkaline cleaning agents with a Formulation containing hydrogen peroxide called, which is not in the concentrate is stable in storage, because the alkalinity leads to a rapid breakdown of the hydrogen peroxides to water and oxygen. When cleaning, however, mixing can of alkaline with hydrogen peroxide-containing compositions immediately  be of clear advantage before use. Besides bleaching colored impurities, e.g. B. blood, fruit and vegetable residues, stamp ink, etc., the cleaning is enhanced by the oxidation reaction. This method can e.g. B. as an ecological alternative to working with chlorine-containing products Procedures are carried out.

In this variant of the method, the two components involved are titrated often not possible, e.g. B. if alkaline together with the double injector system be used with detergents containing hydrogen peroxide. The Determination of the hydrogen peroxide component is because of the rapid dismantling not possible. Therefore, the user has no control or Information about the concentration and consumption of cleaning agents or Disinfectant during the cleaning process. An optimization of the Application solutions are not possible. Reproducible or constant reini agent concentrations or cleaning booster concentrations and / or Cleaning results cannot be achieved. A possible failure of the Reini tion amplifier, which usually has little or no foam formation has an impact, remains unnoticed during the cleaning process. It there is a large hygiene risk. Costly and time-consuming re-cleaning conditions may be necessary.

The titration procedures are time-consuming, prone to errors, and can lead to one Accident and hygiene risks lead and are sometimes not applicable. About that it is also disadvantageous that different aids are required for the titration be, e.g. B. burettes, Peleus balls, Erlenmeyer flasks, indicators, titration chemicals and water for rinsing the devices, if necessary also Scales, stirrers, heating and magnetic stirring plates. Some of these devices are out Glass and are not accepted in food processing plants.

The determination of the concentration by means of a measurement is also known of the conductance. The inductive conductivity is measured. This method is with the application on cleaning and / or disinfection foam considerable fluctuations in measured values. An incomplete one dip the measuring electrode or measure inside the foam or inside half of the mixture of foam and liquid definitely leads to wrong Results.  

Another method for determining the concentration of the detergent or disinfectant in the foam, based on the water used, consists in the so-called calibration. Here the volume of the per unit of time Mixing unit supplied concentrated detergent or disinfectant determined by using a hose to clean or disinfect tion medium is sucked out of a measuring vessel with a scale. at Known flow rate of water can then calculate the concentration become.

None of the methods listed above enables continuous control the concentration of the detergent or disinfectant during the Cleaning or disinfection process or offers statistical evaluation possibilities as well as the possibility to document the present concessions tration of the agent. The statistical evaluation options would be the current one Product consumption, the total product consumption, the consumption per unit of time, etc. beneficial.

As the state of the art which became known in writing and which at the beginning corresponds to the mentioned method and from which the invention is based, in addition to the already mentioned German patent application DE 197 05 861 A1 U.S. Patent No. 4,802,630 (Ecolab Inc.) and international patent application WO 98/188 98 A1 (Unilever N.V.) called.

Compared to the known methods, the object of the invention is in the process of the type mentioned at the outset a continuous, simple, fast and error-free detection and monitoring of the concentration of the cleaning and / or disinfectant in the cleaning or disinfecting foam, ins especially during the cleaning / disinfection process.

This object is fiction, in the method of the type mentioned resolved by continuously increasing the consumption of concentrated Detergent and / or disinfectant measures per unit of time and from it and from the water consumption per unit of time the concentration of the cleaning and / or disinfectant in the foam. Determining consumption is preferably carried out automatically, ie not manually.  

With the invention is a continuous, error-free setting and control of foam used for cleaning and disinfection Composition, namely the concentration of cleaning and disinfecting tion agent, to ensure industrial hygiene and occupational safety simple, quick way possible.

Captured in a particularly simple to use embodiment of the invention one for measuring the consumption of concentrated cleaning and / or Disinfectant whose flow in the line to the mixing unit. The Detection of the flow, the fiction in the further below system implemented by installing a flow meter offers the following further advantages. A continuous and current Measurement of the actual concentration during the cleaning process, So an online measurement is possible. The total consumption, the consumption per Time unit or the current consumption can be recorded and displayed as well also be documented. Even neutral products can be opened without one Record agile titration quickly and accurately. Monitoring and determination the concentration of neutral cleaning agents or disinfectants with low Salinity, the concentration of which cannot be determined with a conductance measurement, can be carried out easily. When using the above Double injector systems allow the concentrations of both components of the Detergent or disinfectant continuously and simultaneously with the Determine cleaning process or disinfection process, i.e. on-line.

Adjustments in concentration and other corrective measures can be taken immediately after finding a deviation from the desired one Concentration can be made so that there is time for optimization significantly shortened. Occurs when adding one component, e.g. B. the Reini tion amplifier on a fault, so that the system, for example, the Component no longer sucks, the fault is immediately noticed and can optionally be indicated by optical and / or acoustic signals become.

In an alternative embodiment of the invention, one measures to measure the Consumption of concentrated cleaning and / or disinfectant  Changing the weight of the storage container for the cleaning and / or disinfectants. For this purpose, the storage container z. B. on scales be put. In addition to the advantages at Consumption is measured here by measuring the flow additional advantages. Since there is no contact of the chemicals with the measurement setup, a particularly trouble-free process is guaranteed. There is none at all Risk of corrosion or crystallization of the cleaning and / or Disinfectant inside the measuring system.

A particularly high level of safety, the prescribed hygiene requirements compliance is achieved if there are deviations in the determined concentration of the Detergent and / or disinfectant from the target concentration optically and / or be displayed acoustically.

To demonstrate compliance with hygiene, as stated in the food regulation is prescribed for food processing companies, it is significant Lich advantage if the determined concentrations of cleaning and / or Disinfectants can be stored electronically and / or printed out. This should already be done during cleaning or disinfection.

Another particularly advantageous embodiment of the invention is that one controls the concentration of cleaning and / or disinfectant, whereby the concentration determined represents the controlled variable. An automated and considerably better and easier compliance with the target concentration than with one manual correction is possible in this way. Personnel expenses for Control of concentration is significantly less.

In certain cases it is beneficial if after starting the foam generation the determination of the concentration of cleaning and / or disinfection agent in the foam only begins after a time delay. This Delay may e.g. B. only a few seconds, especially 2 to 5 seconds be. This delay is particularly advantageous if this is Balance in the mixing unit not immediately, but only after the sets the specified delay. Before setting this balance then there are no problems with a possible regulation or tripping  an alarm signal due to an excessive deviation from the target Concentration on.

The invention also relates to a system for cleaning and / or disinfecting of hard surfaces with an aqueous, cleaning and / or disinfectant foam containing agent, with a mixing unit for water, air and concentrated cleaning and / or disinfectant, the mixing unit Inlet lines for water, air and concentrated cleaning and / or Disinfectant and has an outlet for foam.

The task already mentioned is fiction, in the system mentioned according to the fact that a device for continuous, and ins special automatic, measuring the consumption of concentrated cleaning and / or disinfectant is provided per unit of time.

It is particularly preferred if the device for measuring consumption of concentrated cleaning and / or disinfectant as a flow flow meter in the inlet line for concentrated cleaning and / or Disinfectant is trained. The advantages of this design have been also mentioned above.

In the following, exemplary embodiments of the invention are described with reference to drawing described in more detail. Show it

Fig. 1 is a schematic overview of a system according to a first embodiment OF INVENTION to the invention,

Fig. 2 is a schematic representation of the principle operation of the mixing unit of the plant of Fig. 1,

Fig. 3 shows a detail from Fig. 1,

Fig. 4, the entire structure shown in FIG. 1, but with units of other individual,

Fig. 5 is a schematic overview of a system according to a second embodiment of the invention,

Figure 6, for example. A plant according to a third invention execution,

Fig. 7 is a system according to a fourth embodiment of the invention and example

8 of all of the examples above underlying exemplary structure of the units according to the invention..

In all drawings, the same reference numerals have the same meaning and may therefore only be explained once.

In a first embodiment corresponding to FIGS. 1 to 4, the throughput of the concentrate of cleaning agent or disinfectant sucked in by the mixing unit 1 is detected by a flow meter 2 which is arranged in the suction line 3 for the concentrate. The flow meter is designed here as an oval gear meter 2 . Between the oval wheel meter 2 and the mixing unit 1 , a needle valve 4 is also installed in the suction line 3 , which can optionally be controlled pneumatically.

Further lines 5 for water and a line 6 for compressed air, here with a needle valve 7 and a manometer 8, are connected to the mixing unit 1 . An outlet line 9 for the foam containing the cleaning agent or disinfectant is finally shown in FIG. 1.

The suction of the concentrate in the mixing unit 1 is shown schematically in FIG. 2. The narrowing of the cross section in the Venturi nozzle 10 leads to a negative pressure delta p in the water flowing in from the left, so that concentrate 3 is sucked in through the suction line 3 .

The measuring arrangement with respect to the oval gear meter 2 from FIG. 1 is shown in detail in FIG. 3. The oval gear meter 2 , which has a pulse generator, emits an electrical signal from a signal element 11 to a transducer 12 , which forwards the signal after conversion to a controller 13 , which has a display, a printer and, if appropriate, a regulator.

The measuring arrangement described in FIG. 3 offers the following options in comparison to conventional methods:

• - on-line measurement of concentration
• - Display / printout of current consumption
• - Displaying / printing statistics, namely
• - Consumption per time
• - Total consumption
• - Consumption per line / area
• - Alarm in case of under or over concentration
• - Automatic concentration control
• - Archiving of the measurement data.

The entire structure corresponding to FIG. 1, but with further details, can be seen in FIG. 4. A measured value amplifier 14 can also be arranged between the signal element 11 and the transmitter 12 .

In the line 5 for water, a booster pump 15 is provided, which generates a pressure between 6 and 45 bar. Behind the pump 15 , a second flow meter 16 is installed in the line 5 , which also outputs a signal to the controller 13 .

The concentration of the cleaning agent or disinfectant in the foam, which is released by the mixing unit 1 , can then be calculated in the controller 13 as follows. From the measured volumes of water and concentrate flowing through lines 5 and 3 , and taking into account the known density of the concentrate, the masses of water and concentrate flowing through the lines per unit time are calculated. The concentration of the concentrate then results as the quotient of the mass of the concentrate and the sum of the masses of concentrate and water.

Instead of an oval gear meter 2 , other types of flow meter can be used. Thus, FIG. 5 shows the structure of an OF INVENTION to the invention system, which is used as a flow meter float meter 17 in the intake pipe 3 for the concentrate. The float knife 17 is also known under the name "Rotameter".

These or other types of flow meters can fiction can also be integrated into existing systems.

The following are still other possible methods in the inventive method usable flow meters called, without this list is final.

Different types of measuring devices are used to measure liquids, taking into account the types of liquid, their composition and the specific amount to be measured:

• a) Mechanical volume meters
• b) Mass-Flow Meter
• c) Flow velocity-dependent measuring devices

Types / types: signal output (a = analog, d = digital)

The use of flow meters in the context of the invention offers a number of significant advantages over the prior art.  

The use of titrations and reducing nozzles known from the prior art or conductivity measurements, in contrast, either offers no or only random concentration data. An online display of the actual There is no concentration during cleaning. Accounting for Total consumption, consumption per unit of time or current consumption are not possible.

Flow meters, on the other hand, offer the possibility of on-line consumption display. Is also the water flow (liters per time; measured in the water line z. B. by means of Venturi nozzle), can be convenient (quickly and accurately) determine the concentration of the detergent / disinfectant used.

With oval gear meters there is also the possibility of using pulse generators and measuring value converter to visualize various parameters (display on display or Printout on paper), e.g. B. the current consumption, the total consumption, consumption per unit of time, current concentration, etc.

A third example of the method according to the invention or the system according to the invention can be seen in FIG. 6, which corresponds to FIG. 4. In contrast to the system or the method according to FIG. 4, here is a template container 18 for the concentrate on a scale 19th The weighing signal is sent from the signal element 11 to the transmitter 12 in the manner already described. The advantages of this method are the same as the advantages of the above-mentioned method variants. In addition, there are the advantages that result from the lack of direct contact of the concentrate with the measurement setup, as has already been explained above.

The desired concentration is determined here from the measured throughput of water and the change in mass of the container 18 filled with the concentrate, in each case per unit of time.

A variant of the method shown in FIG. 6 or the corresponding system is shown in FIG. 7. Here you can dose two components independently of each other. For the second component, a separate template container 18 a is provided, which stands on a second scale 19 a. The weighing signal is passed on from a second signal element 11 a to the corresponding measured value amplifier 14 a and the transmitter 12 a, which conducts the converted signal to the controller 13 . The calculation of the individual concentrations of both concentrates in the foam is carried out in a manner corresponding to the calculation in the case of the exemplary embodiment according to FIG. 6.

The use of the methods or systems according to the invention is still to be seen add that the foam produced by means of both manual systems Hose as well as in permanently installed systems by means of a pipe system and Nozzles can be used. The nozzles can be used for cleaning, for example the filler of beverage filling systems.

Finally, Fig. 8 shows the general structure of an embodiment of the system according to the invention, without the invention being restricted to this structure. This drawing is self-explanatory and is therefore not explained in detail.

In the following, measurement results are presented which have been obtained with the arrangements according to FIGS. 4 and 6.

Measuring arrangement according to FIGS . 4 and 6

Water temperature: 50 ° C
Water flow: 10 liters / min.
Water pressure: 10 bar
Cleaning agent: P3-topax 19 (product of Henkel-Ecolab GmbH & Co. OHG)
Density: 1.22 g / ml
Viscosity: 14 mPas
Flow meter: oval gear meter (

FIG.

4)
Gravimetric evaluation: scale (

FIG.

6)
System used: low-pressure foam system from ALTO

The measurement results obtained show the reliability of the invention Method.  

LIST OF REFERENCE NUMBERS

1

mixing unit

2

Flow meter, oval gear meter

3

Suction line for concentrate

4

shut-off valve

5

Pipe for water

6

Line for compressed air

7

shut-off valve

8th

manometer

9

Outlet line for the foam

10

venturi

11

.

11

a signal link

12

.

12

a transmitter

13

controller

14

.

14

a Measured value amplifier

15

Booster pump

16

second flow meter

17

Rotameters

18

.

18

a Storage container

19

.

19

a Libra

Claims (9)

1. A method for cleaning and / or disinfecting hard surfaces with an aqueous foam containing cleaning and / or disinfectant, the foam being obtained by mixing water, air and a concentrated cleaning and / or disinfectant in a mixing unit ( 1 ). generated and wherein the concentration of the detergent and / or disinfectant in this foam, based on the water used, recorded and / or monitored, characterized in that one continuously, and in particular automatically, the consumption of concentrated detergent and / or Disinfectant measures per unit of time and from this and from the water consumption per unit of time determines the concentration of the cleaning and / or disinfectant in the foam. 2. The method according to claim 1, characterized in that one measures the measurement of the consumption of concentrated cleaning and / or disinfectant whose flow in the line ( 3 ) to the mixing unit ( 1 ). 3. The method according to claim 1, characterized in that to measure the consumption of concentrated cleaning and / or disinfectant, the temporal change in the weight of the reservoir ( 18 , 18 a) for the cleaning and / or disinfecting agent is detected. 4. The method according to any one of the preceding claims, characterized, that deviations in the determined concentration of cleaning and / or disinfectant from the target concentration optically and / or be displayed acoustically.   5. The method according to any one of the preceding claims, characterized, that the determined concentrations of cleaning and / or disinfecting tion means are electronically stored and / or printed out. 6. The method according to any one of the preceding claims, characterized, that you have the concentration of detergent and / or disinfectant regulates, the determined concentration being the controlled variable. 7. The method according to any one of the preceding claims, characterized, that after the start of foam generation, the determination of the conc Tration of the detergent and / or disinfectant in the foam only after a time delay begins. 8. Plant for cleaning and / or disinfecting hard surfaces with an aqueous foam containing cleaning and / or disinfectant, with a mixing unit ( 1 ) for water, air and concentrated cleaning and / or disinfectant, the mixing unit ( 1 ) Has inlet lines ( 5 , 6 , 3 ) for water, air and concentrated cleaning and / or disinfectant and an outlet for foam, characterized in that a device ( 2 , 19 , 19 a) for continuous, and in particular automatic, measurement of Consumption of concentrated cleaning and / or disinfectant is provided per unit of time. 9. Plant according to claim 8, characterized in that the device for measuring the consumption of concentrated cleaning and / or disinfecting agent is designed as a flow meter ( 2 ) in the inlet line ( 3 ) for concentrated cleaning and / or disinfecting agent.