WO2013139457A1 - Method for treating process water in the food and beverage industry, and device for carrying out the method - Google Patents

Description

Method for treating process water of the food and beverage industry and device for carrying out the method

In the food and beverage industry, water is needed both for the products themselves and for their production. For the products, the water (product water) must have drinking water quality according to the current Drinking Water Ordinance 2001 (TrinkwVO 2001). In the manufacturing operations, e.g. When removing products from pipelines or when cleaning production plants using the CIP (Cleaning-In-Place) method, the water, which is referred to below as process water, must always have drinking water quality, if the plants or plant components with the products can come into contact. In such manufacturing operations, such as e.g. When heating or cooling, where the water can not come into contact with the products, it does not have to have drinking water quality according to the Drinking Water Ordinance 2001.

In the food industry and the beverage industry, the quantitative ratio between product water and

Process water with drinking water quality different. At a brewery, which will be considered in more detail below, the ratio is about 1 to 3. In a brewery with a beer output of, for example, 1 million hl / a results in addition to the product water, a need for process water with drinking water quality of 2.5 - 3, 0 million hl / a.

The various plant components of a brewery, such as mash tun, lauter tun, wort kettle, whirlpool, fermentation tanks, storage tanks, filtration and bottling plants and their connecting pipes are due to different residence time of the product in them at different times and with different Treatment periods subjected to cleaning. In the case of large-volume plant components, spray cleaning is usually used. In the piping, the cleaning of the individual pipe sections is carried out in the course of a complete filling. In these cleaning operations, cleaning agents, such as sodium hydroxide, are used at least in the initial phase. This is followed by a rinse cycle or several rinses with rinse water, that is to say with process water of drinking water quality, in order to rinse out the cleaning agents and the product residues or contaminants which they have removed from the system components. When extracting the contents of the pipes at the beginning or end of production steps, process water with drinking water quality is also used.

Because of their exposure to detergents, product residues and contaminants, these process water streams including the flush water streams must be disposed of. So far, this happens after the so-called "end-of-pipe"

Procedures, as described in the dissertation by Simon Walter "Investigation of procedural options for process water circulation in the brewery",

TU Munich, from 03.05.2005 is described. This means that these process waters, including the rinsing water streams, undergo a mechanical and / or biological after-treatment. In the best case, a small part of it can be treated to service water and used as process water. The much larger part can continue to be regarded only as wastewater, which is fed together with the treated process water after its reuse as a whole the sewage system. The invention is based on the object, at least to recover the ^¬ jenigen part of the process water, without additional treatment has drinking water quality or with an additional treatment can reach drinking water quality. This object is achieved by a method according to claim 1.

Characterized in that in the place of formation of the Prozesswas ^¬ sers herkommenden drain line at the measuring point by at least one sensor a characteristic feature of the process water is determined, which is important for the decision as to whether it is water with drinking ^¬ water quality or without drinking water quality, can after evaluation of the sensor signal in the control unit, a corresponding control signal is sent to the switch and these are adjusted so that the detected partial flow is directed into the continuing line for drinking water or in the continuing line for contaminated water.

With a further development of the method

Claim 2 can be another criterion or several other criteria for the distinction between drinking water and polluted water are detected. As a result, the separation safety can be increased. In a further development of the method according to

 Claim 3 prevents streams or partial streams of the process water from different sources of origin from meeting in front of the measuring point and mixing with each other and thereby preventing a separate detection.

By a further development of the method

Claim 4 can be made not only either / or decisions but also gradual decisions. In a development of the method according to claim 5, the quality of the partial flow can be raised to a higher quality level at partial streams of process water with small deviations from the target values by the additional treatment and so this partial flow with water with comparable water quality, eg drinking water-like quality, are brought together.

In a further development of the method according to

Claim 6 can raise the quality of the partial stream to a higher quality level in partial streams with low load through the mechanical filtration and thus merge with water comparable water quality. In a further development of the method according to

Claim 7 may be at a partial flow with low

Pollution degree by means of sterile filtration, the quality of the partial flow are raised so much that the partial flow can be used at least as process water.

In a further development of the method according to

Claim 8 you can separate partial streams of process water with relatively low degree of contamination of those part streams with relatively high degree of contamination and the partial flow with the

lowest level of contamination through an additional treatment to provide a higher level of quality. With a further development of the method

Claim 9 is achieved that in a partial flow with a high degree of contamination by the mechanical filtering and / or by the biological treatment, the pollution load is reduced, thereby facilitating the further disposal of the relevant partial flow. The invention is also based on the object of specifying a device with which the method according to claim 1 can be carried out in a favorable manner. This object is achieved by a device having the features specified in claim 10.

Characterized in that in the originating from the source of the process water drain line a measuring point or measuring section is arranged, at least one sensor for at least one characteristic of the

Process water is arranged, such as a sensor for the turbidity and / or a sensor for the pH and / or a sensor for the electrical conductivity and / or a sensor for the density and derived therefrom quality parameter (extract content), and in that the sensor generates a property corresponding measurement ^¬ signal, and in that a control device EXISTING ^¬ is the comparing each measurement signal of a sensor with a reference value and provides a reference signal therefrom, and a plurality of reference signals, a unit ^¬ pending control signal forms, and in that a subsequent to the measuring point section of the drain line is designed as a switch, to the two continuing

Drain lines are connected and which is equipped with an actuator, and in that the

Control unit is coupled via a signal line with the actuators of the switch, the switch is set on the occurrence of a signal characteristic of drinking water, the switch to the corresponding secondary outflow line, whereas it is set on the occurrence of a characteristic of polluted process water signal to the other continuing outflow lines. As a result, those partial streams with drinking water quality that occur in the wake of the rinsing or used as Ausschub- water, in the drinking water cycle to be led back. This reduces both the amount of drinking water to be recovered and the amount of waste water to be disposed of. In one embodiment of the device according to claim 11 or claim 12, it can also be used for treating process water in those areas of the beverage industry, occur in the process water alcohol or organic acids.

With an embodiment of the device according to claim 13, the method according to claim 1 can also be applied to such operations of the food and beverage industry for the treatment of process water, in which due to the operational structure and / or the

 Operation at different locations Process water accumulates, which contains not only contaminated partial flows but also partial flows with drinking water quality, in that the streams or partial flows from different sources do not occur simultaneously but one after another at the measuring point or

Are fed to the measuring section, so that mixing of partial streams of different water quality is avoided. By means of an embodiment of the device according to claim 14, it is achieved that the operating control devices at the sources of production of the process water via the control signal line can act on the selection of the shut-off device and on the time of opening and closing of this shut-off device.

In one embodiment of the device according to claim 15, it is achieved that at least one of the partial flows from the first turnout shares those with less Stress can be separated from those with higher load, whereby they can be subjected according to their properties to a targeted further treatment, without mutual disability.

Characterized in that in one embodiment of the device according to claim 16, the measurement signal is comparable to a two- or multi-level reference value, by means of which a two- or multi-level reference signal is derivable, not only either / or decisions but also gradual decisions can be made and two-stage or multi-stage control signal can be generated, by means of which the switch designed as a triple switch or a multi-turn switch is adjustable to a corresponding operating position, so that the detected partial flow can be passed in one of two or more continuing lines, in the course of the partial flow to different destinations hinleitbar is.

In one embodiment of the device according to claim 17, it is possible to treat the relevant partial flow in a matched to its properties treatment device.

In the following, the invention is based on a in the

Drawing illustrated hydraulic and electrical circuit diagram of a device explained in more detail, from which also the explanations of the method result.

The process water used in the individual production steps and the process water resulting from the cleaning of different parts of the plant are combined in one

Outflow line 2 a treatment and / or disposal supplied. A portion of the drain line 2 is as

Measuring point or measuring section 3 is formed in the Sen- Soren 4 ... 7 are arranged for a characteristic property of the process water, each of which generates a corresponding property of the respective measurement signal. These include in particular the sensor 4 for the turbidity, the sensor 5 for the pH, the sensor 6 for the conductivity and the sensor 7 for the density and the quality parameter derived therefrom (extract content). Their measurement signals are forwarded to an evaluation circuit, which is referred to as control unit 8, in which the incoming measurement signals of the sensors 4 ... 7 are each compared with a predetermined reference signal and from each of which generates a control signal 9, from which a resulting control signal 10 is generated. In order to be able to distinguish the measuring and control signals from one another, they are identified, if necessary, by the reference symbol of the relevant signal line.

The aim of this comparison of the measuring signals with their predetermined reference signals is to determine whether the tested in the measuring section 3 partial flow of process water has drinking water quality or not.

A following on the measuring section 3 section of

Outflow line 2 is designed as a switch 12 to which two further outflow lines 13 and 14 are connected. The switch 12 is equipped with an actuator 15, by means of which the switch 12 is set to the switch position, which corresponds to the resulting control signal 10 of the control unit 8.

In this way, it is above all those partial streams of the process water from the rinsing processes and the partial streams of the discharge water, which are not polluted and have drinking water quality, that can be returned to the drinking water circuit. For ^this' part of the process water is not drinking water must be won. If, in the following, particular attention is given to the conditions in breweries, another sensor 17 for alcohol as a further criterion is of importance in the measuring section 3.

Regardless of the previous sensors 4 ... 7 and 17, it may be important in the measuring section 3 in addition

To arrange a sensor 18 for organic acids, because conclusions can be drawn on an organic load of the process water.

If it is determined during testing of a partial flow that the tested partial flow does not have drinking water quality, then the question still remains whether this partial flow is low, medium or heavily loaded.

If there is only a slight load, check whether this partial flow of process water is in the secondary

Drain line 13 can be raised by a suitable treatment to drinking water quality. For this purpose, for example, a filter 19 may be arranged, whose permeate is pure water or drinking water 21 and whose retentate, e.g. separated contaminants, be disposed of.

In those partial streams of process water that have been derived from the switch 12 in the secondary drain lines 14 because they are not eligible for treatment to drinking water, ie for a treatment to reach the quality of drinking water, it is useful to examine whether they are medium or heavily loaded. For this purpose, a section of the discharge lines 14 is designed as a second measuring section 23. This is the same or at least similar to the first measuring section 12 is formed. The recorded there measuring signals are in the other Control unit 24 evaluated and used to generate a control signal 25, which is sent to a subsequent second switch 26, to adjust them accordingly. This switch 26 is the same or at least similar to the first switch 12 formed and allowed with an actuator 15 ^¬ . To the switch 26 two secondary outflow lines 27 and 28 are connected.

Different treatment devices can be connected to each of the secondary outflow lines 27 and 28, by means of which the partial flows flowing therein can be subjected to a targeted after-treatment which improves their quality or at least facilitates their disposal.

In the apparatus described above, due to the comparison of the measurement signals with only a single reference value, only a one-step decision is possible. In a modified embodiment not shown in the drawing, the first control device as well as the further control device is equipped with a two- or multi-level reference value for one or more of the measurement signals, so that individual or all measurement signals compared with a zugsseigen two- or multi-level reference value can be formed and from a two-or multi-level control signal can be formed.

Then the switch connected thereto can be designed as a triple or as a multiple switch, to which a corresponding number of secondary outflow lines are connected.

Such a triple or multiple diverter can be designed, for example, in the manner of a tap with stopcock, which is operated in the opposite direction to the usual flow direction, ie in which the stopcock is used as an inflow valve. used and in which the valve body has a plurality of outlet openings, to each of which a continuing

Drain line is connected. For operations in which process water accumulates at different locations at different times, ie, for example, the drain lines 2, 29 and 30 have for process water, it is expedient in the

Outflow line 2 before the first measuring section 3 a shut-off device 31 turn on, with a

 Actuator 34 is coupled to turn on in the further drain line 29 a shut-off device 32 which is coupled to an actuator 35 and turn on in the further drain line 30, a shut-off device 33 which is coupled to an actuator 36.

It is also useful after connecting the

Drain lines 29 and 30 and before the first measuring section 3, a flow meter 37 to be arranged, the ent generates either a flow signal or an empty signal. These measurement signals are evaluated by a second control unit 3. With an empty signal of the flow meter 37, the actuator of one of the Absper.rvor directions receives the control command to open this Absperrvor direction. This ensures that only one of the process water flows reaches the measuring section 3 and the measurement result of the other process ^streams can not be disturbed or even falsified.

In addition, it is expedient, the second control unit 38 via a control signal line 41 with the

To connect operating control devices to the place of origin of the process water, so that the operating control devices at the sources of signal line 41 on the selection of the best in

Considering coming shut-off device and can act on the timing of opening and closing this shut-off device.

In very large-scale facilities, it may be appropriate, instead of just one measuring section 3 or a tandem measuring section 3 and 23, two or more such

Measuring sections and the associated system components

To arrange different locations of the site, to avoid overlong connecting lines with a correspondingly large hollow volume. This also applies to the retrofitting of existing facilities.

LIST OF REFERENCE NUMBERS

2 drainage pipe

 3 measuring point / measuring section 4 sensor

 5 sensor

 6 sensor

 7 sensor

 8 control unit

 9 control signal

 10 resulting control signal

12 points

 13 drainage pipe

 14 drain line

15 actuator

 16 partial streams

 17 sensor

 18 sensor

 19 filters

 21 drinking water

 22 Retentate

 23 2nd measuring section

 24 control signal

25 control signal

 26 2. Switch

 27 drain line

 28 drain line

 29 drainage pipe

30 drain line

 31 shut-off device

 32 shut-off device

 33 shut-off device

 34 actuator

35 actuator

 36 ■ Actuator

 37 flowmeter

 38 control unit

 39 control signal

 41 control signal line

Claims

Process for treating process water in the food and beverage industry, with the process steps:  the process water is passed from the point of origin through at least one outflow line (2) to a measuring point , headed (3),  a measurement signal corresponding to the characteristic is generated at the measuring point (3) by means of a sensor (4 ... 7) for at least one characteristic property of the process water,  - The measurement signal is compared in a control unit (8) with a reference value and from a  Control signal (9) is formed,  the process water is passed from the measuring point (3) to a switch (12) with at least two outflow lines (13, 14),  the switch (12) is set by the control signal (9) to the switch position corresponding to the control signal (9),  - The process water is through the open  Outflow line (13:14) forwarded to the connected destination. Method according to claim 1 with the further method steps:  at the measuring point (3), by means of at least one further sensor (17; 18), a further measuring signal corresponding to the further characteristic is generated for at least one further property of the process water, each further measuring signal is compared in the control unit 8 with a reference value and from this a further control signal is formed, - In the control unit (8) from the individual control signals (9) according to predetermined criteria, a resulting control signal (10) is formed, which is forwarded to the switch (12). Method according to claim 1 or 2 with the further method steps:  if different partial streams with different properties are produced at different sources of production of the process water, the different partial streams are conducted according to predetermined criteria by a second control device (38) at different times to the measuring point (3), Method according to one of claims 1 to 3 with the further method step:  - The measurement signals of the existing sensors (4 ... 7) are processed in the control unit (8) by means of a fuzzy logic controller to the control signal or to the resulting control signal (10). Method according to claim 4 with the further method step:  - The stream or the streams of process water are fed to the switch (12) through the relevant discharge line (13; 14) treatment additional treatment. The method of claim 5, comprising the further procedural ^¬ rensschritt: - The stream or streams of process water with a low degree of contamination after the switch (12) tion at least one mechanical Filtrie (19) subjected. Method according to claim 5 or 6, with the further method step:  - The stream or streams of process water with a low degree of contamination after the switch (12) subjected to a sterile filtration. Method according to one of claims 5 to 7, with the further method steps:  the stream or partial streams of the process water having a higher degree of contamination are conducted to the second measuring point or measuring section (23) after the (first) point (12),  - At the second measuring section (23) by means of at least one sensor (4 .. 7) for at least one property of the process water one of  Property corresponding measurement signal generated, the measurement signal is compared in a control unit (24) with a reference value and from this a second control signal (25) is formed,  the process water is passed from the second measuring section (23) to a second switch (26) with at least two outflow lines (27;  - The second switch (26) is set by the second control signal (25) to this control signal (25) corresponding switch position,  - The partial flow of process water with relative  low pollution (average degree of contamination) is passed into the one drain line (27) and the partial stream of process water with relatively high pollution (high degree of contamination) is passed into the other drain line (28). 9. The method according to claim 5 and claim 8, with the further method steps: - The stream or streams of process water with a higher degree of contamination after the first and / or the second switch (26) at least one mechanical filtration (19) and / or subjected to a biological treatment. Device for carrying out the method according to Claim 1, having the features:  - There is a drain line (2) for the process water to be treated,  a section of the discharge line (2) is designed as a measuring point or measuring section (3),  - In the measuring section (3) is at least one  Sensor (4 ... 7) arranged for at least one characteristic property of the process water, which generates a corresponding property of the respective measurement signal, namely  - - A sensor (4) for the turbidity and / or  - - A sensor (5) for the pH and / or  - - A sensor (6) for the electrical conductivity and / or  a sensor (7) for the extract content,  - There is a control unit (8) available,  - - In which each measurement signal of a sensor (4 ... 7) is compared with a reference value and from a reference signal is formed and  in which a uniform control signal (10) is formed from a plurality of reference signals,  a section of the discharge line (2) following the measuring section (3) is designed as a switch (12), - - are connected to the two further discharge lines (13, 14) and - - equipped with an actuator (15) - The control unit (8) via a signal line (10) with the actuator (15)  Switch (12) coupled. Apparatus according to claim 10, having the feature:  - In the measuring section (3), a sensor (17) is arranged for the alcohol content. Apparatus according to claim 10 or 11, having the feature:  - In the measuring section (3), a sensor (18) is arranged for the content of organic acids. Device according to one of claims 10 to 12, having the features:  there is more than one discharge line (2, 29, 30) each from a different place of origin of process water to be treated,  each of these further outflow lines (2; 29; 30) is equipped with a shut-off device (31; 32; 33) which is coupled to an actuator (34, 35; 36), - Before the measuring section (3) of the primary outflow ^¬ line (2) a flow meter (37) is arranged, which generates either a flow signal or an empty signal,  - There is a second control device (38) is present, which evaluates the signals of the flowmeter (37) and at an empty signal, a control signal (39) for opening to one of the shut-off devices (31, 32, 33) of the further discharge lines (2, 29; 30). Apparatus according to claim 13, having the features: - The second control unit (38) is connected via a control signal line (41) with the operation control devices of the origin of the process water Device according to one of claims 10 to 14, having the features:  after the first switch (12), a second measuring section (23) is arranged in the secondary outflow line (14) for loaded process water, the second measuring section (23) is equipped the same or at least similar to the first measuring section (12),  - There is another control unit (24) available, - - In which each measurement signal of a sensor (4 .. 7) of the second measuring section (23) is compared with a reference value and from a reference signal is formed and  in which a single control signal (25) is formed from a plurality of reference signals,  - one on the second measuring section (23) following  Section of the associated discharge line (14) is designed as a switch ■ (26),  - - are connected to the two secondary drain lines (27; 28) and  - - which is equipped with an actuator (29), - The further control unit (24) is coupled via a signal line (25) with the actuator (29) of the second switch (26). 16. Device according to one of claims 10 to 12, having the features:  in the first control device (8) and / or the further control device (24), at least one of the measuring signals is compared with a two-stage or multi-stage reference value, from which a two-stage or multi-level reference signal thereof is a two-stage or multi-stage control signal,  - The connected switch is designed as a triple switch or as a multiple switch, which is equipped with a two- or multi-stage actuator, by means of which the switch is adjustable according to the two- or multi-stage control signal to a corresponding operating position. 17. Device according to one of claims 10 to 16, having the feature:  - An additional treatment device is connected to at least one of the further outflow lines (21; 22; 27; 28).