Abstract:
An apparatus for batched mixing of an additive component from individual components for mixture products containing the additive component and for temporarily storing the additive component, which is part of a mixer for forming the mixture products by mixing an additive component with a base component includes a single batch tank connected by at least a control valve and/or a proportioning valve to connections supplying the individual components for proportioned introduction of the individual components. The single batch tank is connected to a mixing and buffer tank arranged on a level below the single batch tank for temporary storage of the mixed additive component.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is the national stage entry under 35 USC 371 of International Application No. PCT/EP2010/007408, filed Dec. 7, 2010, which claims the benefit of the Feb. 16, 2010 priority date of German Application No. 10 2010 008 165.5. The contents of the aforementioned applications are incorporated herein in their entirety. 
     FIELD OF DISCLOSURE 
     This disclosure relates to mixing devices for mixing products, and in particular, to a device for batched mixing of an additive component. 
     BACKGROUND 
     For the production of mixture products, one generally combines am additive component with a base component. The additive component is itself made by mixing individual components. Examples of additive components include components that provide flavor, and/or color, as well as components that promote preservation of the mixture product. Examples of mixture products include drinks, such as mixed drinks, including soft drinks or lemonades. An example of a base component is water. 
     A typical plant for mixing drinks includes a tank for degassing the base component, one or more admixture devices and/or mixing sections for the metered admixture of the additive component, an optional carbonating device for carbonating the mixed drink, and a storage device for temporarily storing the mixed drink. 
     In the case of mixed drinks, the additive component is sometimes referred to as “syrup.” The syrup is usually premixed from the individual components in a separate premixing space, which is often called a “syrup space.” The syrup is then brought from this syrup space to a mixing device. At the mixing device, the syrup is diluted and blended with the degassed base component until it reaches its final concentration. The degassed base component is typically water 
     Within the syrup space, known devices for the pre-proportioning or premixing of the additive components in the separate syrup space feed individual components into an associated batch tank. To ensure proportionality, they typically do so under the control of flow-meters or load cells. These known devices either use very large receiver tanks or alternate between two batch tanks that are connected in parallel. The two batch tanks are usually designed to hold enough volume so that one can fill continuously while the other is being refilled. 
     One disadvantage of these known devices is that all arriving or departing pipes, including fittings, mixing pumps, and mixing systems, must be replicated. Another disadvantage is the high investment costs that arise as a consequence of both the need to replicate all these parts, and the need to provide such large container volumes. 
     Other known methods and mixing devices are configured for inline proportioning. In such devices, the individual components are introduced into the mixer in parallel inline into the base component. 
     One disadvantage of these mixing devices arises from their considerable technical complexity. Each individual component requires its own proportioning leg. Each such leg will include, among other things, a header vessel, a level measurement, a feed controller, a pump, flow-meters, and a volume control valve. 
     A further disadvantage of the mixing device is that the pumps are running most of the time. As a result, these pumps will heat up. Inevitably, this heat is transferred to the individual components. If the volumes of liquid are large, this heat is easily dissipated without causing a significant temperature rise. However, the individual components are used in only small amounts. As a result, waste heat from the pump can be enough to raise their temperature considerably. This heating can result lead in product damage. 
     In known methods for inline proportioning, it is desirable to make redundant measurements of the added individual components to ensure product quality. In particular, it is desirable to check measured-data provided by flow-meters, such as mass flow-meters and volumetric flow-meters, or to check data provided by weighing scales used for the proportioning, as well as to execute inline control measurement methods for detecting faulty measurements or incorrect proportions. In known devices, these redundant measurements are either not possible or highly complex. 
     SUMMARY 
     The invention provides a way to significantly reduce the investment volume for a complete plant for producing mixture products, in particular mixed drinks. 
     In one aspect, the invention integrates a device for mixing individual constituents to form an additive component into a mixer that adds this additive component to a base component, such as water. This eliminates the need to provide a separate premixing space or syrup space, this configuration achieves a considerable reduction in the investment volume of a complete plant. 
     When the mixture product is a mixed drink, examples of an additive component include a flavoring component, a coloring component, a preserving component, or any combination thereof. 
     In another aspect, the invention features an apparatus with only a single batch tank for the mixing of an additive component from its individual components. During each proportioning cycle, all individual components required by a recipe for the additive component are introduced in a proportioned manner. Preferably, these individual components are introduced one after the other. At the end of each proportioning cycle the resulting additive component is drained into a buffer tank through a liquid connection, preferably in free fall. As a result, intensive blending of the individual components already occurs in the liquid connection, before the additive component reaches the buffer tank. 
     As used herein, the phrase “batched mixing of the additive components” refers to a process in which additive component is made in batches rather than continuously. Such a process is divided into proportioning cycles. During each such proportioning cycle, individual components of an additive component are fed into a batch tank in the correct proportions. The batch tank is then emptied into a mixing-and-buffer tank. 
     Further embodiments, advantages and possible applications of the invention arise out of the following description of embodiments and out of the figures. All of the described and/or pictorially represented attributes whether alone or in any desired combination are fundamentally the subject matter of the invention independently of their synopsis in the claims or a retroactive application thereof. The content of the claims is also made an integral part of the description. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The invention is explained in detail below through the use of an exemplary embodiment and with reference to the figures, in which: 
         FIG. 1  shows, in a simplified function diagram, a mixing plant or mixing device for mixing a base component with a syrup, with the syrup itself being made from at least two individual components; and 
         FIG. 2  shows a schematic functional representation of a closed cross-valve (item a) and open cross-valve (item b). 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  shows a mixing device  1  that produces mixture products, such as drinks. The mixing device  1  does so by mixing a liquid base component GK with an additive component ZK, carbonating the resulting mixture, and then storing it. The base component GK is typically water. The additive component ZK is usually a blended syrup. 
     The blended syrup is a flavoring component, a coloring component, and/or a component that promotes preservation. To make the additive component ZK, one mixes a plurality of individual components K 1 -K 5 . The individual components usually include a dominant component K 5  and subdominant components K 1 -K 4 . The dominant component K 5  is the component that is used in the largest quantity when making the additive component ZK. 
     The mixing device  1  has four functionally distinct plant sections  1 . 1 - 1 . 4 . These plant sections are: a base-preparation section  1 . 1 , a mixture-product mixing section  1 . 2 , an additive-component mixing section  1 . 3 , and a carbonation section  1 . 4 . 
     The base-preparation section  1 . 1  prepares the base component GK by degassing. The additive-component mixing section  1 . 3  mixes the additive component ZK from individual components K 1 -K 5  according to a particular predetermined recipe. The mixture-product mixing section  1 . 2  then takes one or more additive components ZK and admixes them into the base component GK to form a mixture product. Finally, the carbonation section  1 . 4  carbonates and buffers the mixture product. 
     The base-preparation section  1 . 1  comprises a base-component tank  2  to which the base component GK is fed in the required quantity during the operation of the mixing device  1  in such a way that the base-component tank  2  is partly filled under level control with the base component GK. The base-component tank  2  has a lower liquid space  2 . 1  and a gas space  2 . 2  that lies above the liquid space  2 . 1 . A vacuum line  3  connects the gas space  2 . 2  to a vacuum source, such as a vacuum pump. This permits degassing the base component GK. 
     A base-supply line  4  carries the base component GK from the base-component tank  2  to a point at which it combines with additive component ZK and becomes mixture product. The base-supply line  4  then continues on to a buffer tank  5 . A product line  6  connects the buffer tank  5  to a filling machine (not shown) for filling containers with the mixture product. 
     In the depicted embodiment, the base-supply line  4  has a first base-supply-line connection-valve  7  and a second base-supply-line connection-valve  8 . The first base-supply-line connection-valve  7  and the second base-supply-line connection-valve  8  are disposed sequentially in the direction of flow from the base-component tank  2  to the buffer tank  5 . 
     The first base-supply-line connection-valve  7  introduces concentrated aqueous sugar solution into the base component GK to sweeten the mixture product. A suitable sugar solution is a 70% sugar solution. The second base-supply-line connection-valve  8  introduces additive component ZK into the base component GK. 
     In the direction of flow following the second base-supply-line connection-valve  8 , a section of the base supply-line  4  upstream of the buffer tank  5  forms a carbonating leg  9  in which in-line carbonating takes place. Within the carbonating leg  9 , the base supply-line  4  has a carbonating-leg flow-meter  10 . 
     Downstream of the carbonating-leg flow-meter  10 , just before the buffer tank  5 , is a buffer-tank flow control valve  11 . Upstream of the carbonating-leg flow-meter  10 , a CO2 line  12  opens via at least one nozzle orifice. The CO2 line  12  connects to a CO2 source (not shown) that provides pressurized CO2 gas. The CO2 line  12  has a CO2 flow-meter  13  for measuring the quantity of CO2 gas flowing through it, and a CO2 flow-metering valve  14 . Control electronics (not shown) controls the CO2 flow-metering valve  14  as a function of measurement signals from the CO2 flow-meter  13  and the carbonating-leg flow-meter  10  such that the mixture product has the specified CO2 content after inline carbonation on the carbonating leg  9 . 
     For the proportioned addition of sugar or sugar-concentrate, a sugar line  15  connects the open first base-supply line connection valve  7  to a source of sugar concentrate. Proceeding along the sugar line  15  starting from the source of sugar concentrate, there is a sugar-line flow-meter  16 , a sugar/large component flow-metering valve  17 , the first base-supply-line connection-valve  7 , and a shut-off or gully valve  18 . During actual admixing of sugar to the base component GK, the gully valve  18  remains closed. When purging or cleaning the sugar line  14 , the gully valve  18  opens to drain the sugar line  15  into a sugar-line drain  18 . 1 . 
     Admixing the liquid sugar through the first base-supply line connection valve  7  directly into the base component GK significantly reduces the throughput demand on the additive-component mixing section  1 . 3 . However, liquid sugar can also be added in the additive-component mixing section  1 . 3 . In such cases, the liquid sugar would usually be the dominant component K 5 . 
     The additive-component mixing section  1 . 3  is what makes the additive component ZK. It is here that the proportioned mixing of additive component ZK from individual components K 1 -K 4  takes place. 
     The additive-component mixing section  1 . 3  comprises a shared proportioning line  19  and a dedicated proportioning line  20 . The shared proportioning line  19  is shared among the subdominant components K 1 -K 4 . The dedicated proportioning line  20  is dedicated to the use of the dominant component K 5 . 
     Separate individual-component supply valves  21  form separate connections between the shared proportioning line  19  and sources of the individual components K 1 -K 4 . The individual components K 1 -K 4  are components that are present in the additive component ZK in very small amounts, and thus form a very small mass fraction. 
     A dominant-component supply valve  22  forms a connection between the dedicated proportioning line  20  and a source of the dominant component K 5 . The dominant component K 5  is the component that forms the greatest mass fraction or quantity fraction in the additive component ZK. A shared-proportioning line flow-meter  23  is provided in the shared proportioning line  19 . Similarly, a dedicated proportioning line flow-meter  24  is provided in the dedicated proportioning line  20 . The shared-proportioning line flow-meter  23  and the dedicated-proportioning line flow-meter  24  can be mass flow-meters or volumetric flow-meters. A proportioning feed pump  25  is also provided in the dedicated proportioning line  20  upstream of the second flow-meter  24 . 
     In the direction of flow of the components K 1 -K 5  and downstream respectively of the fourth and fifth flow-meters  23 ,  24 , corresponding first and second proportioning-line valves  26  connect the shared and dedicated proportioning lines  19 ,  20  to a master line  27 . The master line  27  connects a lower inlet and outlet of a header or a batch tank  28  to a mixing-and-buffer tank  29 . The mixing-and-buffer tank  29 , which is beneath the batch tank  28 , holds the additive component ZK. A master-line shut-off valve  30  in the master line  27  provides a way to interrupt the connection between the mixing-and-buffer tank  29  and the master line  27 , the dedicated proportioning-line  20 , and the shared proportioning-line  19 . 
     An additive-component-supply line  31  connects to the outlet of the mixing-and-buffer tank  29  for carrying additive component ZK. Along the additive-component-supply line  31  are, starting from mixing-and-buffer tank  29 , a proportioning or circulation pump  32 , a sixth flow-meter  33 , which can be a mass flow-meter or a volumetric flow-meter, a concentrate-flow metering valve  34 , the second base-supply line connection valve  8 , and a shut-off or gully valve  35  with which the end of the additive-component-supply line  31  that is away from the mixing-and-buffer tank  29  can be either closed or drained towards a second drain  35 . 1 . 
     The rated flow of the proportioning-or-circulating pump  32  is set so that its generated volumetric flow exceeds the maximum amount of additive component ZK that is to be admixed to the base component GK. The partial quantity of additive component ZK that is not required is returned to the mixing-and-buffer tank  29  through an additive-component-return line  31 . 1 . The admixing of additive component ZK to the base component GK is effected when the second base-supply-line connection-valve  8  is open through the concentrate-flow metering valve  34 . This opening is triggered by the control electronics as a function of the signals from the sixth flow-meter  33  and a further flow-meter provided in the base line  4 . A suitable flow-meter provided in the base line  4  is the carbonating-leg flow-meter  10 . 
     In a proportioning cycle, the individual components K 1 -K 5  are proportioned in chronological order or are introduced into the batch tank  28  in the quantities and/or fractions according to the particular recipe as a function of the measurement signals of the fourth and fifth flow-meters  23 ,  24 , with at least one of components K 1 -K 4  being aspirated by vacuum. This aspiration results from having the batch tank  28  be connected to a gas space  2 . 2  of the tank  2  by a vacuum line  36  that has a vacuum-regulating valve  37 . This avoids the need for an additional vacuum source. 
     In some cases, it is desirable to separate the individual components in the shared proportioning line  19  and the master line  27  during the proportioning cycle. This can be achieved by having one of individual components K 1 -K 4  be water. In such cases, briefly opening the associated individual-component supply valve  21  results in passage of a water plug through the shared proportioning line  19  and the master line  27  into the batch tank  28 . 
     In some embodiments, a proportioning feed pump  25 , with possible assistance of a vacuum, introduces the dominant component K 5  into the batch tank  28 . However, other embodiments dispense with the proportioning feed pump  25  by sucking the dominant component K 5  into the batch tank  28  in a proportioned manner as well. 
     Among the advantages of using a dedicated proportioning line  20  for the dominant component K 5  is that the subdominant components K 1 -K 4  can be proportioned with greater accuracy through an appropriate configuration of the fourth and fifth flow-meters  23 ,  24 . The use of a dedicated proportioning line  20  also allows the proportioning of the dominant component K 5  to be carried out at the same time as the proportioning of subdominant components K 1 -K 4 . 
     Once all individual components K 1 -K 5  that are required by the recipe for the additive component ZK have been introduced into the batch tank  28 , the proportioning cycle ends. At this point, the proportioning line valves  26  close and the master-line shut-off valve  30  opens. This empties the content of the batch tank  28  into the mixing-and-buffer tank  29 . 
     The arrangement is preferably selected such that after the master-line shut-off valve  30  has been opened, the content of the batch tank  28  can flow through the master line  27  in free fall or flow. As the individual components fall, they mix together. Accordingly, the master line  27  is designed with a suitably large cross-section. As it is being emptied, a vent valve  38  opens to bring the batch tank  28  to ambient pressure. It is also possible to accelerate the emptying by pressurizing the batch tank  28 . 
     It is particularly advantageous to redundantly measure and/or check whether the individual components, and in particular, of the subdominant components K 1 -K 4 , are being added in the correct proportions. There are three ways to do this: measuring flow, weighing, and inspecting a liquid level. 
     The first way to perform such a check is to have a further flow-meter and/or a level-meter  39  at either the inlet or the outlet of the batch tank  28 . The second way is to have weigh scale that weighs how much of each individual component K 1 -K 5  is introduced into the batch tank  28 . The third way is to measure the height of the liquid level in the batch tank  28 . When this third method is used, having different diameters in different sections of the batch tank  28 , as shown in the figure, will enhance measurement accuracy. 
     Regardless of which method is used, the redundancy measurement can be carried out in all cycles for all individual components K 1 -K 5 . To save time, however, this can also be done at intervals, for example per batch or cycle, and only for whichever individual component is first introduced into the batch tank  28 . In this case, the individual component that is first introduced into the batch tank  28  changes randomly. Alternatively, individual components take turns being the first to be introduced into the batch tank  28 . 
     In some embodiments, the batch tank  28  has a small enough volume so that the time required to individual components in the correct proportions, when added to the time required to empty the batch tank  28  into the mixing-and-buffer tank  29  is very short cycle. In some of these embodiments, these two times, when added together, amount to under five minutes. 
     Some embodiments include partitions that divide the interior of the mixing-and-buffer tank  29 . This provides the mixing-and-buffer tank  29  with a rudimentary “first-in/first-out characteristic.” 
     In some embodiments, return feeding of the partial stream through the vacuum line  31 . 1  promotes blending of the individual components in the mixing-and-buffer tank  29 . As a result, at least for certain suitable products, there is no need for mechanically actuated mixing and/or agitating elements to ensure complete mixing of additive component ZK. 
     The first and second base-supply-line connection valves  7 ,  8  are preferably cross valves having a configuration that transitions between an open state, shown in  FIG. 2( b ) , and a closed state, shown in  FIG. 2( a ) . An open state of the base-supply-line connection valves  7 ,  8  forms a connection between the sugar line  15 , the additive-component-supply line  31 , and the base-supply line  4 . A closed state of the base-supply-line connection valves  7 ,  8  blocks this connection and also makes it possible to purge the sugar line  15  or the additive-component-supply line  31  after opening the gully valve  18 ,  35 , for example during a working cycle of mixing device  1  when the connection is not needed. 
     At the end of the filling of a certain product or certain product batch, while the mixing-and-buffer tank  29  is being emptied, additive component ZK can already be prepared in the batch tank  28  for the next product batch according to the new recipe and can then be drained off into the mixing-and-buffer tank  29  after the latter has been completely emptied or run empty. 
     A mixing device  1  as described herein can be used to produce mixture products based on a recipe by mixing a base component GK with at least one individual component K 1 -K 5 , and with all the individual components K 1 -K 5  standing ready at the corresponding connections of the shared and dedicated proportioning lines  19 ,  20  but with the controlled opening of the individual-component supply valves  21  and the dominant-component supply valve  22  only introducing those individual components K 1 -K 5  into the batch tank  28  that are actually needed for the current recipe. 
     The invention has been described hereinbefore by reference to one embodiment. It goes without saying that numerous variations and modifications are possible without departing from the inventive concept underlying the invention.