DE202018100763U1 - Water softening system with determination of a regenerant concentration over a delivery time and a delivery volume or a delivery mass - Google Patents

Abstract

Water softening system (1), comprising
a softening device (4a), in particular comprising at least one container (4) with ion exchange resin (5),
- A storage vessel (6) in which a regenerant solution (24) is stored, in particular wherein in the storage vessel (6) and solid regeneration salt (7) is included,
an injector (8) for transporting regenerant solution (24) from the storage vessel (6) to the softening device (4a),
- An electronic control device (9) which is adapted to drive in a regeneration operation, a conveying of the regenerant solution (24) from the storage vessel (6) in the softening device (4a),
characterized,
the water softening system (1) is set up in a conveying step
to predetermine or measure a volume V1 or a mass M1 of promoted regenerant solution (24) (106),
and to predetermine or measure a time duration t1 for the conveyance of the volume V1 or the mass M1 (108),
and in that the electronic control device (9) is set up with a stored calibration function, in particular comprising one or more stored calibration characteristics, a concentration C _{RM1 of} the promoted regenerant _solution (24) and / or a quantity dependent on the concentration of the promoted regenerant solution (24) , in particular one contained in the promoted regenerant solution (24) Amount of salt SM1, from V1 or M1 and / or from t1 (116, 118, 140).

Description

Background of the invention

• - eine Enthärtungsvorrichtung , insbesondere umfassend mindestens einen Behälter mit Ionentauscherharz,
• - ein Vorratsgefäß, in welchem eine Regeneriermittellösung bevorratet ist, insbesondere wobei in dem Vorratsgefäß auch festes Regeneriersalz enthalten ist,
• - einen Injektor für einen Transport von Regeneriermittellösung aus dem Vorratsgefäß zur Enthärtungsvorrichtung,
• - eine elektronische Steuervorrichtung, die dazu eingerichtet ist, in einem Regenerationsbetrieb ein Fördern der Regeneriermittellösung aus dem Vorratsgefäß in die Enthärtungsvorrichtung anzusteuern.

The invention relates to a water softening system comprising

• a softening device, in particular comprising at least one container with ion exchange resin,
• a storage vessel in which a regenerant solution is stored, in particular wherein the storage vessel also contains solid regenerating salt,
• an injector for transporting regenerant solution from the storage vessel to the softening device,
• - An electronic control device which is adapted to drive in a regeneration operation, a conveying of the regenerant solution from the storage vessel in the softening device.

Such a water softening system is from the DE 10 2010 028 756 A1 known.

Water softening systems are used when, for technical or comfort reasons, softened water is desired or needed. Softening devices of water softening systems are typically based on the principle of the ion exchanger. The hardness formers calcium ions and magnesium ions are exchanged by non-hardening ions, usually sodium ions. The water to be softened is passed through an ion exchange resin.

However, an ion exchange resin can bind only a limited amount of hardness agents. Upon depletion of the ion exchange resin, a solution of a regenerant, usually a saline solution, is passed over the ion exchange resin.

In a typical water softening system, the solution of the regenerant is prepared by storing solid regenerating salt in a storage vessel and filling the storage vessel with water. By dissolving a part of the regenerating salt, a saturated regenerant solution is formed, wherein in a lower part of the storage vessel not yet dissolved regeneration salt remains. For regeneration, a portion of the saturated regenerant solution is pumped from the storage vessel, diluted with additional water and fed to the softener. To provide additional saturated regenerant solution, the reservoir is refilled with water and further solid regenerating salt is dissolved.

The dissolution of the solid regenerating salt in the storage vessel is a comparatively slow process. Therefore, in practice, the solution of regenerant in the storage vessel is not yet saturated when pumped out for regeneration. The rate at which solid regenerating salt dissolves depends, for example, on the dosage form (for example, a tablet size), the container geometry of the storage vessel, or also on the temperature. The temperature also affects the concentration at which saturation occurs.

The concentration of the regenerant solution, which is conveyed from the storage vessel, can therefore vary. Accordingly, a working concentration of dilute regenerant solution used to regenerate the ion exchange resin in the softening apparatus may also vary. Incorrect information about the concentration or the amount of salt contained in a regeneration agent solution provided for the regeneration of a softening device can lead to an inefficient use of regenerating salt, an incomplete regeneration of the softening device or even to a misjudgment with regard to the solid regenerating salt still remaining in the storage vessel.

From the DE 10 2010 028 756 A1 It is known to determine the concentration of a regenerant solution in a storage vessel of a water softening system, or also the working concentration of a dilute regenerant solution which is obtained after mixing the regenerant solution with a dilution water stream at an injector with a conductivity sensor. The concentration of the diluted regenerant solution is readjusted via an electronic control unit.

Since the conductivity sensor is placed in a medium containing much salt, this is subject to considerable corrosion. The conductivity sensor must therefore be replaced regularly, which causes effort and costs, and the measured values obtained are often faulty.

The DE 10 2015 219 619 A1 describes a water softening system in which an electronic control device controls the filling and flushing of a brine of a resin container of a water softening system. The system includes a variable injector with which the concentration of brine can be adjusted. In a storage vessel, a saturated salt solution is kept. Water softening systems with injectors for diluting a concentrated regenerant solution, for example, from the DE 195 38 617 A1 , the DE 43 13 468 A1 and the DE 42 21 013 C1 known.

From the Wikipedia article "jet pump", retrieved on 2.2.2008, for example, the pump principle of an injector is known. A driving medium emerges at high speed from a motive nozzle, and entrains a suction medium in a mixing chamber. The pumping effect is stronger, the higher the relative density of the propellant in relation to the suction medium.

Object of the invention

It is an object of the invention to provide a water softening system with which the use of salt can be easily and reliably checked during regeneration of the softening device.

Description of the invention

• - ein Volumen V1 oder eine Masse M1 an geförderter Regeneriermittellösung vorzugeben oder zu messen,
• - und eine Zeitdauer t1 für die Förderung des Volumens V1 oder der Masse M1 vorzugeben oder zu messen,

und dass die elektronische Steuervorrichtung dazu eingerichtet ist, mit einer gespeicherten Kalibrierfunktion, insbesondere umfassend eine oder mehrere gespeicherte Kalibrierkennlinien, eine Konzentration C_RM1 der geförderten Regeneriermittellösung und/oder eine von der Konzentration der geförderten Regeneriermittellösung abhängige Größe, insbesondere eine in der geförderten Regeneriermittellösung enthaltene Salzmenge SM1, aus V1 oder M1 und/oder aus t1 zu bestimmen.This object is achieved by a water softening system of the type mentioned, which is characterized
that the water softening system is set up in a conveying step

• - a volume V1 or a mass M1 to specify or measure at promoted regenerant solution,
• - and a period of time t1 for the promotion of the volume V1 or the mass M1 pretend or measure

and in that the electronic control device is set up with a stored calibration function, in particular comprising one or more stored calibration characteristics, a concentration C _{RM1 of} the promoted regenerant _solution and / or a quantity dependent on the concentration of the promoted regenerant _solution , in particular a quantity of salt contained in the promoted regenerant solution SM1 , out V1 or M1 and / or out t1 to determine.

The invention proposes to determine the concentration C _RM1 of the regenerant _solution present in the storage vessel or a _variable dependent on C _RM1 by means of a calibration function. This calibration function exploits the relationship between the delivery rate of the injector and the density ratio of the suction medium (in this case the aspirated regenerant solution) to the driving medium (in this case, a propulsion water jet from dilution water / raw water). With increasing density of the regenerant solution, and thus with increasing concentration of the regenerant solution, the suction power decreases; Note that the density of the motive water jet does not vary appreciably in practice. Therefore, from the knowledge of a funded volume V1 or from a subsidized mass M1 at regenerant solution and the time duration t1 , which was required for this promotion, be closed under otherwise known conditions, in particular for the given type of plant, on the concentration of the regenerant. The connection between concentration on the one hand and V1 / M1 and t1 On the other hand, it is possible to determine in advance for a specific type of installation and, if necessary, for other conditions (such as for different motive water pressures or motive water flows); This will preserve the calibration function. In particular, in a learning phase before the control operation for each different predetermined (or conventionally measured) concentrations of regenerant solution and optionally for other conditions in each case a ratio of V1 or M1 to t1 determined / measured (or, if one of the sizes V1 / M1 or t1 is given, each other's size V1 / M1 or t1 determined / measured).

At least one of the sizes V1 / M1 and t1 is measured at a conveying step within the scope of the invention. As a rule, one of the sizes V1 / M1 or t1 predetermined (by the type of water softening system, or by the electronic control device), and the other is measured; but it is also possible that both sizes V1 / M1 and t1 be measured.

The sizes V1 / M1 and t1 are predetermined or measured for a conveying step, with a regeneration usually comprising only one conveying step; but it is also possible that a regeneration comprises several successive stages of promotion. Between two regenerations (phases of the regeneration operation) one softening operation (one phase of the softening operation) takes place in each case.

The specific concentration C _{RM1 according to} the _{invention of} the _recirculated (ie extracted from the storage vessel) regenerant _solution or the size dependent _thereon can be used to correctly track the consumption of solid regenerating salt for the provision of the regenerant, so in good time before a full consumption of solid regenerating in the Storage vessel to cause a refill. Refilling is preferably automatic (controlled by the electronic control device), but can also be done manually after a corresponding alarm message. Furthermore, the determination of C _RM1 or the quantity dependent _thereon can be used to optimize the working _{concentration} of dilute regenerant solution in the softening device, in particular to keep it in a range in which a maximum salt utilization for regeneration is achieved. In addition, it is also possible to detect a threatening or occurred, altogether too low brining of the softening device in a regeneration, which leads to an incomplete regeneration of the softening device; In this case, compensation measures (preferably automatically by the electronic control device) can be initiated, such as a shortening of the subsequent softening operation, or a post-salting in the still running regeneration.

In the context of the invention, it is not necessary to expose a conductivity sensor of the corrosive regenerant solution. The information required for the invention in the regeneration operation, such as the duration t1 or the volume delivered V1 or the mass M1 , can be easily and accurately determined without the corrosivity of the regenerant solution would be problematic. A volume specification can be done for example via a float switch and the geometry of the storage vessel, which are not appreciably affected by salt; the same applies to a mass (change) determination, which can be done with a weighing device outside the storage vessel. Even a time measurement or timing is not affected by the salt of the regenerant solution.

Preferred embodiments of the invention

In a preferred embodiment of a water softening system according to the invention, it is provided that the water softening system is set up for a volume of a conveying step V1 or a mass M1 pretend promoted regenerant solution, and a period of time t1 for the promotion of the volume V1 or the mass M1 and that the electronic control _{device is adapted} to measure the concentration C _RM1 and / or the concentration-dependent quantity t1 to determine. A fixed requirement of V1 or M1 in a conveying step is easily possible, for example by the design of the water softening system with float switch or by a weighing device, especially in corrosive regenerant solution, and the duration t1 is also easy to measure. By the fixed specification of V1 / M1 In addition, the calibration function is simplified; the size V1 / M1 is then no longer a variable of the calibration function. Alternatively, it is also possible for a predetermined by the control device, fixed period of time t1 to pump with the injector and the volume delivered during this time V1 or the mass produced during this time M1 to measure regenerant solution. Also in this case, a particularly simple calibration function can be obtained; the size t1 is then no longer a variable of the calibration function.

Also preferred is an embodiment in which the water softening system comprises a pressure reducer with which a fixed inlet pressure pe is ensured at the injector, and the calibration function for this inlet pressure pe is determined. At a given, constant inlet pressure pe, the flow rate of the motive water in the injector is precisely defined. The calibration function becomes particularly simple, because the inlet pressure pe is no longer a variable of the calibration function. It only needs to be determined in advance a calibration curve for this pressure pe and deposited in the electronic control device. Note that the calibration function may, if desired, also include multiple calibration characteristics for different input pressures pe in order to use the controller with different pressure reducers; the input pressure pe determined by the selected pressure reducer is then typically announced once upon startup of the water softening system to the controller, and the corresponding calibration characteristic for that input pressure is preset. The pressure reducer may be located at the inlet of the water softening system or in an outlet to the injector.

Also advantageous is an embodiment which provides that the water softening system comprises a pressure sensor with which a driving water pressure p1 is determinable before the injector, and that the electronic control _{device is adapted} to the concentration C _RM1 or the concentration-dependent variable with the calibration function as a function of p1 to determine. The motive water pressure affects the motive water volume flow and thus the suction power of the injector. The driving water pressure measured with the pressure sensor p1 can be considered as a variable in the calibration function; For example, different calibration curves are stored in the electronic control device for different values of the motive water pressure. Regardless of the local pressure conditions, the correct calibration characteristic can be selected.

Also advantageous is an embodiment which provides that the water softening system comprises a flow meter with which a motive water volume flow V (t) _TW is determined directly or indirectly, and that the electronic control _{device is adapted} to the concentration C _RM1 or the concentration-dependent variable with the calibration function as a function of V (t) _TW to determine. The motive water flow rate determined by the flow meter V (t) _TW can be considered as a variable in the calibration function; For example, different calibration curves are stored in the electronic control device for different values of the motive water volume flow. The suction behavior of the injector depends on the motive water volume flow V (t) _TW from. This can be taken into account when selecting the calibration characteristic. The flow meter can be in the flow direction upstream of the injector in the motive water flow V (t) _TW be arranged (direct measurement) or in the flow direction after the injector in the mixed water volume flow V (t) _MW (indirect measurement, this results in the motive water volume flow V (t) _TW from the measured mixed water volume flow V (t) _MW minus the time t1 and the volume V1 or the mass M1 derived regenerant solution volume flow V (t) _RM ).

Particularly preferred is an embodiment in which the electronic control device is adapted to a amount of salt contained in the promoted regenerant solution SM1 to be determined, in particular from the concentration C _RM1 and the volume V1 or from the concentration C _RM1 , the mass M1 and a concentration- _dependent density function D (C _RM1 ) of the promoted regenerant _solution . About the (in a conveying step) funded amount of salt SM1 For example, the amount of salt SM _REG used for regeneration can be checked and adjusted. In most cases, there is only one pumping step per regeneration (with volume V1 or mass M1 ) intended; in this case SM1 = SM _REG . However, it is also possible to assemble a regeneration from a multiplicity of successive delivery steps (with volumes Vi and masses Mi or salt quantities SMi); in this case, SM _REG = ΣSMi. over SM1 For example, the remaining amount of solid regenerating salt in the storage vessel can be accurately followed, or even insufficient salting for a complete regeneration of the softening device (or even an unnecessarily heavy salting) can be easily detected.

• - in der laufenden Regeneration in einem weiteren Förderschritt ein zusätzliches Volumen V2 oder eine zusätzliche Masse M2 an Regeneriermittellösung aus dem Vorratsgefäß in die Enthärtungsvorrichtung zu fördern,
• - und/oder ein vorgegebenes Volumen V1 und/oder eine vorgegebene Masse M1 und/oder eine vorgegebene Zeitdauer t1 für nachfolgende Regenerationen zu vergrößern,
• - und/oder die Dauer eines nachfolgenden Enthärtungsbetriebs gegenüber einer Standarddauer, die ohne Unterschreiten des Sollwerts SW1 angewandt würde, zu verkürzen,

und/oder im Falle einer Überschreitung von SW1 durch SM1 oder einer Überschreitung von SW1 durch SM1 um mehr als einen Schwellwert

• - ein vorgegebenes Volumen V1 und/oder eine vorgegebene Masse M1 und/oder eine vorgegebene Zeitdauer t1 für nachfolgende Regenerationen zu verkleinern. Diese Maßnahmen sind vor allem für den Fall vorgesehen, eine Regeneration (in der Regel) mit einem einzelnen Förderschritt durchzuführen. Ansonsten können Förderschritte aufeinanderfolgend durchgeführt werden, bis ΣSMi schließlich SW1 erreicht hat. Ein typischer Schwellwert liegt beispielsweise bei 10% Abweichung vom Sollwert. Bei Unterschreiten von SW1 erfolgt keine vollständige Regeneration der Enthärtungsvorrichtung mehr. Bei unvollständiger Regeneration verringert sich die Enthärtungskapazität des darauffolgenden Enthärtungsbetriebs. Durch (iteratives oder unmittelbares) Anpassen des vom Injektor geförderten Volumens bzw. der vom Injektor geförderten Masse oder Verlängerung der Pumpzeit können die Enthärtungskapazität und der Salzverbrauch optimiert werden. Bei Unterschreiten von SW1 (was durch eine Alarmmeldung angezeigt werden kann) kann zudem ein Nachfüllen von festem Regeneriersalz erforderlich sein, oder auch eine Verlängerung einer Salzlösezeit zur Herstellung der Regeneriermittellösung. Gegebenenfalls kann die elektronische Steuereinrichtung solche Maßnahmen auch automatisch veranlassen. Bei Salzmangel im Vorratsgefäß und/oder zu kurzen Salzlösezeiten ist die Konzentration der Regeneriermittellösung zu gering. Wird ein definiertes, vorgegebenes Volumen V1 bzw. eine Masse M1 von dieser Regeneriermittellösung für die Regeneration verwendet, so ist entsprechend auch die eingesetzte Salzmenge zu gering, d.h. der Sollwert SW1 wird unterschritten.

An advantageous development of this embodiment provides that a first setpoint SW1 for a quantity of salt to be used per regeneration of the softening device is stored in the electronic control device, and that the electronic control device is adapted to
in case of underrun of SW1 by SM1 or a shortfall of SW1 by SM1 by more than a threshold

• - In the ongoing regeneration in a further delivery step an additional volume V2 or an additional mass M2 to promote regenerant solution from the storage vessel into the softening device,
• - and / or a given volume V1 and / or a predetermined mass M1 and / or a predetermined period of time t1 for subsequent regeneration,
• - And / or the duration of a subsequent softening operation compared to a standard duration, without falling below the setpoint SW1 would be applied to shorten

and / or in case of exceeding SW1 by SM1 or exceeding SW1 by SM1 by more than a threshold

• - a given volume V1 and / or a predetermined mass M1 and / or a predetermined period of time t1 to reduce for subsequent regenerations. These measures are intended above all for the case of carrying out a regeneration (as a rule) with a single conveying step. Otherwise, delivery steps can be performed sequentially until ΣSMi finally SW1 has reached. For example, a typical threshold is 10% deviation from the setpoint. When falling below SW1 there is no longer complete regeneration of the softening device. Incomplete regeneration reduces the softening capacity of the subsequent softening operation. By (iteratively or directly) adjusting the volume delivered by the injector or the injector pumped up mass or extension of the pumping time, the softening capacity and the salt consumption can be optimized. When falling below SW1 (which may be indicated by an alarm message) may also be a refill of solid regenerating salt may be required, or an extension of a salt dissolution time for the preparation of the regenerant solution. Optionally, the electronic control device can also cause such measures automatically. In the case of a salt deficiency in the storage vessel and / or too short salt dissolution times, the concentration of the regenerant solution is too low. Will be a defined, given volume V1 or a mass M1 used by this regenerant solution for regeneration, then the amount of salt used is correspondingly too low, ie the target value SW1 is fallen short of.

The water softening system can then continue to operate with reduced softening capacity or the subsequent installation is briefly supplied with hard (or harder) water. Likewise, the water flow can be completely interrupted. When exceeding SW1 The measures taken reduce the salt consumption so that no more salt has to be consumed than is needed for a complete regeneration.

Also preferred is an embodiment in which the electronic control _{device is adapted} to determine a working concentration C _{RM2 of} the dilute regenerant solution in the softening _device , in particular from the concentration C _{RM1 of} the pumped regenerant _solution , a _{motive water volume flow} V (t) _TW and a regenerant solution volume flow V (t) _RM , The working concentration can be adjusted iteratively. The correct choice of the working concentration C _{RM2 of} the dilute regenerant solution in the softening device gives optimum salt utilization with a simultaneously good regeneration rate. The (average) regenerant volume flow can over V1 and t1 or over M1 , D (C _RM1 ) and t1 be determined.

• - einen Treibwasservolumenstrom V(t)_TW zu vergrößern, und/oder im Falle einer Unterschreitung von SW2 durch C_RM2 oder einer Unterschreitung von SW2 durch C_RM2 um mehr als einen Schwellwert
• - einen Treibwasservolumenstrom V(t)_TW zu verringern. Das Treibwasser verdünnt die Regeneriermittellösung aus dem Vorratsgefäß. Zwar wird mit zunehmendem Treibwasservolumenstrom V(t)_TW auch das Saugverhalten des Injektors verbessert und damit der Regeneriermittellösungsvolumenstrom V(t)_RM erhöht, jedoch fällt der Verdünnungseffekt des zunehmenden Treibwasservolumenstroms V(t)_TW bei üblicherweise auftretenden Fließgeschwindigkeiten mehr ins Gewicht. Über eine entsprechende Einstellung des Treibwasservolumenstroms kann die Regeneriermittellösung der Konzentration C_RM1 gezielt auf eine gewünschte Arbeitskonzentration C_RM2 eingestellt werden. Ein typischer Schwellwert liegt beispielsweise bei 10% Abweichung vom Sollwert.

In an advantageous development of this embodiment, it is provided that a second desired value SW2 for a working _{concentration} C _RM2 of dilute regenerant solution to be used in regeneration in the softening device is stored in the electronic control device, and that the electronic control device is adapted to
in case of exceeding SW2 by C _RM2 or exceeding of SW2 by C _RM2 by more than one threshold

• - A motive water volume flow V (t) _TW to enlarge, and / or in the case of falling short of SW2 by C _RM2 or _below SW2 by C _RM2 by more than one threshold
• - A motive water volume flow V (t) _TW to reduce. The motive water dilutes the regenerant solution from the storage vessel. Although with increasing motive water volume flow V (t) _TW also improves the suction of the injector and thus the regenerant solution volume flow V (t) _RM increases, but the dilution effect of the increasing motive water flow rate drops V (t) _TW at commonly occurring flow rates more significant. By means of a corresponding adjustment of the _{motive water volume flow} , the regenerant _{solution of} the concentration C _RM1 can be _{adjusted in a} targeted _manner to a desired working concentration C _RM2 . For example, a typical threshold is 10% deviation from the setpoint.

• - eine Abweichung von C_RM1 von SW3 oder eine Abweichung von C_RM1 von SW3 um mehr als einen Schwellwert bei mehreren aufeinanderfolgenden Förderschritten oder Regenerationen aufgetreten ist, und/oder
• - ein Mittelwert C_RM1mittel von Konzentrationen C_RM1 aus mehreren aufeinanderfolgenden Förderschritten oder Regenerationen von SW3 abweicht oder um mehr als einen Schwellwert von SW3 abweicht, und/oder
• - sowohl eine Vergleichskonzentration C_RM1vergleich der Regeneriermittellösung, bestimmt mit einem anderen Verfahren als in Anspruch 1 beschrieben, als auch die nach Anspruch 1 bestimmte Konzentration C_RM1 von SW3 abweichen oder um mehr als einen Schwellwert von SW3 abweichen. Bei dieser Ausführungsform werden einzelne Messfehler bzw. Messungenauigkeiten ignoriert, oder es findet eine doppelte Absicherung mit mehreren Bestimmungsverfahren statt, um eine korrekturbedürftige Konzentration der Regeneriermittellösung festzustellen, so dass unnötige Korrekturmaßnahmen unterbleiben. Ein anderes Verfahren zur Bestimmung von C_RM1vergleich kann beispielsweise gravimetrische oder konduktometrische Messungen umfassen. Korrekturmaßnahmen sind beispielsweise ein Nachfüllen von festem Regeneriersalz oder eine Änderung einer Salzlösezeit; mit diesen Korrekturmaßnahmen kann C_RM1 unmittelbar beeinflusst werden. Andere Korrekturmaßnahmen können eine Anpassung von V1/M1 oder t1, von V(t)_TW oder auch der zu nutzenden Enthärtungskapazität zwischen zwei Regenerationen umfassen; diese Korrekturmaßnahmen verändern zwar nicht C_RM1, aber können die Folgen eines vom Sollwert SW3 abweichenden Werts von C_MR1 ausgleichen.

In an advantageous embodiment, it is provided that the electronic control _device is set up to determine the concentration C _{RM1 of} the promoted regenerant _solution that a third setpoint SW3 for a regeneration-based concentration C _{RM1 of} the regenerant _solution is stored in the electronic control _device , and that the electronic control _{device is adapted} to take corrective action only if

• - a deviation of C _RM1 from SW3 or a deviation of C _RM1 from SW3 has occurred by more than one threshold at several consecutive feed steps or regenerations, and / or
• a mean value C _RM1 of concentrations C _RM1 from several successive production _steps or regenerations of SW3 deviates or more than a threshold of SW3 deviates, and / or
• - Both a comparison _{concentration} C _RM1vergleich the regenerant, determined by a method other than described in claim 1, as well as the determined according to claim 1 concentration C _RM1 of SW3 deviate or more than a threshold of SW3 differ. In this embodiment, individual measurement errors or inaccuracies are ignored, or it is doubled Securing with multiple determination procedures to determine a concentration of the regenerant solution in need of correction so that unnecessary corrective action is omitted. Another method of determining C _{RM1 comparison} may _include , for example, gravimetric or conductimetric measurements. Corrective measures are, for example, replenishment of solid regenerating salt or a change in salt dissolving time; With these corrective _actions , C _RM1 can be directly influenced. Other corrective measures may include an adjustment of V1 / M1 or t1 , from V (t) _TW or also the softening capacity to be used between two regenerations; While these corrective _actions do not alter C _RM1 , they can be the consequences of a setpoint SW3 compensate for the deviating value of C _MR1 .

Also preferred is an embodiment in which the water softening system means for presetting and / or measurement of the volume V1 for a conveying step, in particular a float switch and / or a suction edge and / or an overflow edge of the storage vessel and / or one or more flow meters. The means may also comprise a predetermined geometry of the storage vessel. For example, a reservoir can be completely filled with it prior to delivery of the regenerant solution, and in a conveying step the regenerant solution can be completely emptied, or a defined volume is taken up to a stop level by means of a float switch. With a float switch, a suction edge or an overflow edge, a volume which can be sucked off can be defined in a simple manner, corresponding to the container geometry of the storage vessel. A flow meter may be located directly in a suction line of the regenerant; Also, two flow meters for determining the motive water flow rate V (t) _TW and the mixed water volume flow V (t) _MW be set to the regenerant solution volume flow V (t) _RM to determine a difference.

Also preferred is an embodiment in which the water softening system means for presetting and / or measurement of the mass M1 includes, in particular a weighing device for the storage vessel. By means of a weighing device (balance), the weight of the storage vessel including its contents can be determined and therefrom M1 be determined. For example, this can be a difference M1 of the weight at the beginning and at the end of the regenerant solution removal may be determined, or a regenerant solution withdrawal may be terminated when a predetermined mass decrease of M1 is reached (during the removal no water flows into the storage vessel). Gravimetric measurements (in particular M1 Measurements) can also be used to calculate (together with V1 ) to derive the concentration of the regenerant _solution in the storage vessel C _RM1 . The value thus obtained can then serve as a comparison value C _RM1vergleich , to secure the obtained according to claim 1 value for C _RM1 .

An embodiment in which the water softening system comprises a time measuring device and / or a timer is also preferred. With the time measuring device, for example, the (in advance unknown) time duration t1 be measured, which is needed to a given volume V1 or a given mass M1 to promote with the injector. With the timer can a predetermined time t1 can be given (counted down) while the regenerant solution is being delivered by the injector and the volume delivered in the given time V1 or a mass delivered in the specified time M1 is being measured.

Also advantageous is an embodiment in which a conductivity sensor for determining the conductivity of the promoted regenerant solution is also present. Via the conductivity sensor, a concentration of the regenerant solution can be determined. The concentration C _{RM1 comparison obtained in this way} can be compared with that of the concentration C _RM1 determined according to claim 1.

• - eine Enthärtungsvorrichtung, insbesondere umfassend mindestens einen Behälter mit Ionentauscherharz,
• - ein Vorratsgefäß, in welchem eine Regeneriermittellösung bevorratet ist, insbesondere wobei in dem Vorratsgefäß auch festes Regeneriersalz enthalten ist,
• - ein Injektor für einen Transport von Regeneriermittellösung aus dem Vorratsgefäß zur Enthärtungsvorrichtung,
• - eine elektronische Steuervorrichtung,

wobei in einem Regenerationsbetrieb ein Fördern der Regeneriermittellösung aus dem Vorratsgefäß in die Enthärtungsvorrichtung mit der elektronischen Steuervorrichtung angesteuert wird,
ist dadurch gekennzeichnet,
dass beim Fördern der Regeneriermittellösung in einem Förderschritt

• - ein Volumen V1 oder eine Masse M1 an geförderter Regeneriermittellösung vorgegeben oder gemessen wird,
• - und eine Zeitdauer t1 für die Förderung des Volumens V1 oder der Masse M1 vorgegeben oder gemessen wird,

und dass die elektronische Steuervorrichtung mit einer gespeicherten Kalibrierfunktion, insbesondere umfassend eine oder mehrere gespeicherte Kalibrierkennlinien, eine Konzentration C_RM1 der geförderten Regeneriermittellösung und/oder eine von der Konzentration der geförderten Regeneriermittellösung abhängige Größe, insbesondere eine in der geförderten Regeneriermittellösung enthaltene Salzmenge SM1, aus V1 oder M1 und/oder aus t1 bestimmt. Durch das Verfahren kann auf einfache und zuverlässige Weise die Konzentration der aus dem Vorratsgefäß abgesaugten (geförderten) Regeneriermittellösung, oder auch eine von dieser Konzentration abhängige Größe, bestimmt werden. Das Verfahren kann insbesondere auf einer oben beschriebenen, erfindungsgemäßen Wasserenthärtungsanlage ausgeführt werden. Die elektronische Steuervorrichtung kann dabei den Verfahrensablauf automatisiert vorgeben.A possible method for operating a water softening system, wherein the water softening system comprises

• a softening device, in particular comprising at least one container with ion exchange resin,
• a storage vessel in which a regenerant solution is stored, in particular wherein the storage vessel also contains solid regenerating salt,
• an injector for transporting regenerant solution from the storage vessel to the softening device,
• an electronic control device,

wherein, in a regeneration operation, a delivery of the regenerant solution from the storage vessel into the softening device is controlled by the electronic control device,
is characterized
in conveying the regenerant solution in a conveying step

• - a volume V1 or a mass M1 specified or measured at the funded regenerant solution,
• - and a period of time t1 for the promotion of the volume V1 or the mass M1 given or measured,

and in that the electronic control device with a stored calibration function, in particular comprising one or more stored calibration characteristics, a concentration C _{RM1 of} the promoted regenerant _solution and / or a size dependent on the concentration of the promoted regenerant _solution , in particular a quantity of salt contained in the promoted regenerant solution SM1 , out V1 or M1 and / or out t1 certainly. By the method can be determined in a simple and reliable way, the concentration of extracted from the storage vessel (promoted) regenerant solution, or a dependent of this concentration size. The method can be carried out in particular on a water softening system according to the invention described above. The electronic control device can specify the procedure automatically.

Further advantages of the invention will become apparent from the description and the drawings. Likewise, according to the invention, the above-mentioned features and those which are still further developed can each be used individually for themselves or for a plurality of combinations of any kind. The embodiments shown and described are not to be understood as exhaustive enumeration, but rather have exemplary character for the description of the invention.

list of figures

• 1 eine schematische Darstellung einer Ausführungsform einer erfindungsgemäßen Wasserenthärtungsanlage;
• 2 ein schematisches Ablaufdiagramm einer ersten Variante eines Verfahrens zum Betrieb einer Wasserenthärtungsanlage gemäß der Erfindung, wobei ein vorgegebenes Volumen V1 gefördert wird und eine eingesetzte Salzmenge SM1 auf einen ersten Sollwert SW1 eingestellt wird;
• 3 ein schematisches Ablaufdiagramm einer zweiten Variante eines Verfahrens zum Betrieb einer Wasserenthärtungsanlage gemäß der Erfindung, wobei ein vorgegebenes Volumen V1 gefördert wird und eine Arbeitskonzentration C_RM2 von verdünnter Regeneriermittellösung in einer Enthärtungsvorrichtung auf einen zweiten Sollwert SW2 eingestellt wird;
• 4 ein schematisches Ablaufdiagramm einer dritten Variante eines Verfahrens zum Betrieb einer Wasserenthärtungsanlage gemäß der Erfindung, wobei ein vorgegebenes Volumen V1 gefördert wird und eine Konzentration von Regeneriermittellösung C_RM1 im Vorratsgefäß auf einen dritten Sollwert SW3 eingestellt wird;
• 5 ein Diagramm zur Abhängigkeit der Injektor-Saugzeit für ein vorgegebenes Volumen V1 von der Konzentration der Regeneriermittellösung bei einem ersten Eingangsdruck von pe=2bar;
• 6 ein Diagramm zur Abhängigkeit der Injektor-Saugzeit für ein vorgegebenes Volumen V1 von der Konzentration der Regeneriermittellösung bei einem zweiten Eingangsdruck von pe=4bar;
• 7 ein Diagramm zur Abhängigkeit der Injektor-Saugzeit für eine vorgegebene Masse M1 von der Konzentration der Regeneriermittellösung bei einem ersten Eingangsdruck von pe=2bar;
• 8 ein Diagramm zur Abhängigkeit der Injektor-Saugzeit für eine vorgegebene Masse M1 von der Konzentration der Regeneriermittellösung bei einem zweiten Eingangsdruck von pe=4bar.

The invention is illustrated in the drawing and will be explained in more detail with reference to embodiments. Show it:

• 1 a schematic representation of an embodiment of a water softening system according to the invention;
• 2 a schematic flow diagram of a first variant of a method for operating a water softening system according to the invention, wherein a predetermined volume V1 is promoted and an amount of salt used SM1 to a first setpoint SW1 is set;
• 3 a schematic flow diagram of a second variant of a method for operating a water softening system according to the invention, wherein a predetermined volume V1 and a working concentration C _RM2 of dilute regenerant solution in a softening device to a second desired value SW2 is set;
• 4 a schematic flow diagram of a third variant of a method for operating a water softening system according to the invention, wherein a predetermined volume V1 is promoted and a concentration of regenerant _solution C _RM1 in the storage vessel to a third setpoint SW3 is set;
• 5 a diagram of the dependence of the injector suction time for a given volume V1 from the concentration of the regenerant solution at a first inlet pressure of pe = 2bar;
• 6 a diagram of the dependence of the injector suction time for a given volume V1 from the concentration of the regenerant solution at a second inlet pressure of pe = 4bar;
• 7 a diagram of the dependence of the injector suction time for a given mass M1 from the concentration of the regenerant solution at a first inlet pressure of pe = 2bar;
• 8th a diagram of the dependence of the injector suction time for a given mass M1 from the concentration of the regenerant solution at a second inlet pressure of pe = 4bar.

The 1 shows an embodiment of a water softening system according to the invention 1 in a schematic overview.

About a feed 2 for raw water flows from a local water network, such as the drinking water network, the water softening system raw water, so not softened water. The raw water should be subjected to a partial or complete softening.

At the inlet 2 is a pressure reducer 12 arranged, which adjusts the water pressure in the subsequent water softening system to a constant inlet pressure pe, for example, pe = 2 bar.

In a softening plant, the raw water flows when the valve is closed 20 completely a control head 9a to which for a full softening the raw water through a softening device 4a who heads here with a container 4 containing ion exchange resin 5 is trained. The softened water then flows into a drain 3 for softened water too. If only a partial softening is desired, the raw water flow in the control head 9a on a partial flow to be softened by the softening device 4a and a bypass flow to be split before the expiration 3 be reunited (not shown in detail).

The ion exchange resin 5 must be regenerated regularly. For this purpose, an electronic control device 9 , here in the steering head 9a is integrated, switch to a regeneration mode. The from the control device 9 used measuring and control cables are in 1 shown dotted; the control device 9 basically controls the entire softening and regeneration operation of the water softening system. In the regeneration mode, the sequence is shown in the embodiment shown 3 over the steering head 9a directly with the inlet 2 for raw water connected to the drain 3 to provide a temporary water supply with non-softened water (not shown).

To the regeneration of the ion exchange resin 5 to be able to make the water softening system 1 over a storage vessel 6 , in which solid regenerating salt 7 , here saline (NaCl) in tablet form, is stored. Over the lines 18 and 19 can with the valve closed 20 and open valve 21 from the steering head 9a from raw water into the storage vessel 6 be filled. The solid regenerating salt 7 is partially dissolved in the filled raw water, creating a regenerant solution 24 a concentration C _{RM1 is} obtained. If the dissolution time is sufficiently long, a saturated regenerant solution is obtained; in practice, however, the (complete) saturation often occurs until the regenerant solution is used 24 not reached.

regenerating 24 can with an injector 8th from the storage vessel 6 be pumped by a motive water flow V (t) _TW raw water from the inlet 2 over the open valve 20 and the line 17 the injector 8th is supplied. The motive water flow stream breaks over the pipe 18 regenerating 24 as regenerant volume flow V (t) _RM with, whereby a mixed water volume flow V (t) _MW in line 19 with V (t) _TW + V (t) _RM = V (t) _MW . The mixed water volume flow V (t) _MW contains diluted regenerant solution; this is for the purpose of regeneration of the ion exchange resin 5 over the steering head 9a the softening device 4a fed. Spent dilute regenerant solution may overflow 22 a sewer 23 be supplied.

The concentration of dilute regenerant solution in the softener 4a is referred to as working _{concentration} C _RM2 . The motive water volume flow V (t) _TW may in the embodiment shown via a flow meter 13 be followed.

At the end of a previous regeneration, the liquid level became 14a in the storage vessel 6 first by the control device 9 to the upper level 15 set; to set this upper level 15 here serves a float switch 14 , Since in the softening mode the liquid level 14a in the storage vessel 6 does not change, is at the beginning of the current regeneration, the regenerant solution 24 still with the liquid level 14a at the upper level 15 ,

At the beginning of the current regeneration are by the electronic control device 9 the valves 20 and 21 opened, causing regenerant solution 24 from the injector 8th aspirated and as a dilute regenerant solution of the softening device 4a is supplied. At the same time a time measurement with a time measuring device 10 the electronic control device 10 started.

Once the liquid level 14a in the storage vessel 6 the lower level 16 has reached, pumping out of regenerant solution 24 from the control device 9 stopped, for example by closing the valves 20 . 21 , Likewise, the timing is stopped. Reaching the lower level 16 will turn here through the float switch 14 registered.

The volume V1 on pumped regenerant solution 24 is through the two through the float switch 14 defined levels 15 and 16 and the container geometry (here the base of the storage vessel 6 ) specified for this promotion step of regenerant solution. The with the time measuring device 10 measured time duration t1 the removal of this volume V1 of regenerant solution V1 can now from the control device 9 are evaluated to determine the concentration C _{RM1 of} the regenerant _solution .

Because of the pressure reducer 12 the inlet pressure pe at the injector 8th is fixed, one for this input pressure pe and for the given volume is sufficient V1 for the water softening system used 1 determined calibration curve as a calibration function to from the period t1 the concentration C _{RM1 of} the regenerant _solution 24 to determine. Such a certain concentration C _RM1 can be shown on the display 11 the electronic control device 9 are displayed.

und Volumen V1 dividiert werden, mit $${\text{C}}_{\text{RM2}}=\left(\text{V}1*{\text{C}}_{\text{RM1}}\right)/\left({\displaystyle \sum _{t1}V{\left(t\right)}_{TW}}+\text{V1}\right).$$

By an amount of salt used in the conveying step SM1 to determine the volume V1 are multiplied by the determined concentration C _RM1 with SM1 = V1 * C _RM1 . To the working _{concentration} C _{RM2 of} the dilute regenerant solution in the softening device 4a can determine the amount of salt used SM1 by the sum of over time t1 accumulated (integrated) motive water volume flow ${\displaystyle \underset{t1}{\Sigma }V{\left(t\right)}_{TW}}$

and volume V1 be divided with $${\text{C}}_{\text{RM2}}=\left(\text{V}1*{\text{C}}_{\text{RM1}}\right)/\left({\displaystyle \underset{t1}{\Sigma }V{\left(t\right)}_{TW}}+\text{V1}\right),$$

Note that instead of V1 also about the mass M1 the subsidized regenerant solution 24 and the concentration- _dependent density D (C _RM1 ) can be worked with V1 = M1 / D (C _RM1 ). For this purpose, the Vorrastgefäß 6 with a weighing device 26 can be equipped, and a termination of pumping regenerant solution can when reaching the predetermined mass difference M1 respectively.

If desired, the water softening system 1 also a pressure sensor 25 in line 17 show, with the water pressure in front of the injector 8th is determinable. In fluctuating pressure conditions, especially if no pressure reducer 12 used, so can the motive water pressure p1 be taken into account and taken into account in the determination of the concentration C _RM1 by the calibration function.

Likewise, if desired, a conductivity sensor 27 be used, such as in the pipe 18 with which additionally the concentration of the regenerant solution can be monitored and a comparison concentration C _RM1 comparison can be determined conductometrically. As a result, a very high level of safety in the concentration determination can be achieved, however, the conductivity sensor 27 exposed to a rather corrosive medium.

The 2 illustrates in a schematic flow diagram a method for operating a water softening system (for example, as in 1 presented) according to the invention in a first variant.

After the start 100 In the process, the water softening plant first enters a phase of softening operation 102 in which raw water is passed through the softener to obtain softened water. At regular intervals (alternatively, continuously) is checked by the electronic control device, if the softening device is exhausted and therefore a regeneration is required 104 , For this purpose, a remaining softening capacity of the softening device is preferably monitored by the control device, and a regeneration is triggered when a limit value is reached.

If regeneration is required, the water softener will go into a regeneration mode. In a conveying step, the control device in the illustrated variant activates the injector, the predetermined volume V1 to promote regenerant solution from the storage vessel 106 and diluted to supply the softening device. The control device measures the time required for this t1 108 , Furthermore, it is provided here, the prevailing during the promotion of the regenerant solution motive water flow V (t) _TW to eat 110 or the driving water pressure p1 before the injector 112 (If a pressure reducer is used, the corresponding inlet pressure pe can also be queried here, which is then replaced by p1 occurs). For the detected motive water volume flow V (t) _TW or the determined motive water pressure p1 (and for the given volume V1 ) then a suitable stored calibration characteristic is selected 114 , which is used as part of the calibration function. With the selected Calibration characteristic then becomes the concentration C _{RM1 of} the regenerant _solution from the time period t1 certainly 116 , In addition, in the variant shown, the amount of salt used in the conveying step also becomes SM1 which is contained in the promoted regenerant solution determined 118 , with SM1 = V1 * C _RM1 .

Subsequently, the control device checks whether a stored first setpoint value SW1 from SM1 is fallen short of 120 ; if desired, a drop below can only be regarded as relevant if the underflow exceeds a threshold value, for example more than 10% in relation to the setpoint SW1 , If an undershoot is detected, the controller initiates one or more of the following countermeasures: an additional volume V2 of regenerant solution from the storage vessel into the softening device 122 , in a subsequent regeneration (not the current regeneration) the predetermined V1 enlarge 124 , shorten the next phase of the softening operation 126 , and / or extend the salt dissolution time in the storage vessel 128 , Subsequently, the remaining phase of the regeneration operation 130 completed, in particular waiting for a reaction time of the dilute regenerant solution on the ion exchange resin, rinsing out the spent regenerant solution from the softener and refilling the storage vessel with water.

If the setpoint SW1 is not undershot, is then checked by the control device, whether a stored setpoint SW1 from SM1 is exceeded 132 ; if desired, exceeding may only be considered relevant if the exceedance exceeds a threshold value, for example more than 10% with respect to the target value SW1 , If an exceeding is determined, the control device causes as a countermeasure that in a subsequent regeneration (not the current regeneration), the predetermined V1 is reduced 134 , Subsequently, the remaining phase of the regeneration operation 130 completed.

After the end of the regeneration operation phase 130 the process will proceed to a next phase of the softening operation 102 continued.

The 3 illustrates in a schematic flow diagram a method for operating a water softening system (for example, as in 1 presented) according to the invention in a second variant. The process steps 100 to 114 according to the expiry of 2 (see above).

In one step 140 Here is determined by the electronic control device, the working _{concentration} C _RM2 of dilute regenerant solution in the softening, with ${\text{C}}_{\text{RM2}}=\text{V1}*{\text{C}}_{\text{RM1}}/\left({\displaystyle \underset{t1}{\Sigma }V{\left(t\right)}_{TW}}+\text{V}1\right),$

Subsequently, the control device checks whether a stored second setpoint value SW2 _falls below C _RM2 142 ; if desired, a drop below can only be regarded as relevant if the underflow exceeds a threshold value, for example more than 10% in relation to the setpoint SW2 , If an undershoot is detected, the controller causes, in a subsequent regeneration (not the current regeneration) of the motive water flow V (t) _TW is reduced 144 ; For this purpose, an adjustable throttle valve can be used in front of the injector. Subsequently, the remaining phase of the regeneration operation 130 completed.

If the setpoint SW2 is not undershot, is then checked by the control device, whether a stored setpoint SW2 is exceeded by C _RM2 146 ; if desired, exceeding may only be considered relevant if the exceedance exceeds a threshold value, for example more than 10% with respect to the target value SW2 , If an overshoot is detected, the control device causes, as a countermeasure, that in a subsequent regeneration (not the current regeneration) of the motive water flow V (t) _TW is enlarged 148 , Subsequently, the remaining phase of the regeneration operation 130 completed.

If both reviews 142 . 146 have led to a negative result (ie the setpoint SW2 is neither exceeded nor exceeded), is also the remaining phase of the regeneration operation 130 completed.

After the end of the regeneration operation phase 130 the process will go to the next phase of the softening operation 102 continued.

The 4 illustrates in a schematic flow diagram a method for operating a water softening system (for example, as in 1 presented) according to the invention in a third variant. The process steps 100 to 116 according to the expiry of 2 (see above).

Subsequently, it is checked by the control device, whether a stored third setpoint SW3 _falls below C _RM1 160 ; if desired, a drop below can only be regarded as relevant if the underflow exceeds a threshold value, for example more than 10% in relation to the setpoint SW3 , If an undershooting is detected, it is further checked by the control device, even if a (relevant) underrun of also during previous phases of the regeneration operation (for example, the two immediately preceding phases of the regeneration operation) SW3 by C _RM1 162 or whether a comparison _{concentration} C _{RM1comparison} for the promoted regenerant _solution measured by another method (such as a conductimetric method) is also the threshold value SW3 falls below (relevant) 164 , If so, the electronic control device initiates appropriate corrective action 166 For example, an extension of the salt dissolving time for the solid regenerating salt in the storage vessel, or a refill of solid regenerating salt in the storage vessel. Subsequently, the remaining phase of the regeneration operation 130 completed. Likewise, the remaining phase of the regeneration operation is continued 130 when the review 160 or both reviews 162 . 164 came to a negative result.

After the end of the regeneration operation phase 130 the process will go to the next phase of the softening operation 102 continued.

The 5 shows in a diagram for an embodiment of a water softening system according to the invention experimentally determined suction times (durations t1 ) for aspirating a predefined volume V1 from here 0.5 l of regenerant solution at various concentrations, here expressed in% of the saturation concentration of the regenerant. The inlet pressure pe was set to pe = 2 bar with a pressure reducer. The average of three measurements, which are reproduced in the following table, is entered in the diagram: Table for FIG. 5: Suction times at V1 = 0.5l, pe = 2bar Concentration [%] Time Time Time Average Measurement 1 Measurement 2 Measurement 3 [S] 0 119 119 119 119 33 126 125 125 125.3 66 129 128 128 128.3 100 (saturated) 133 132 132 132.3

The suction time required to aspirate 0.5 L of regenerant solution from the reservoir increases as the concentration of the regenerant solution increases. The course is (nearly) linear, and can (for the volume V1 and the inlet pressure pe = 2 bar) as a calibration curve for determining the concentration as a function of the time duration t1 Serve (suction time).

Note that the suction time is directly proportional to the specified volume, so that the suction times which can be taken from the diagram (possibly by extrapolation) can also be converted to volumes other than V1 = 0.5 l, and in particular also measured volumes.

The 6 illustrates the experimentally determined absorption times (time periods t1 ) for sucking off the predefined volume V1 0.5 l of regenerant solution at various concentrations for the same water softening system as in 5 , Deviating from 5 the inlet pressure pe was set here to a pe = 4 bar with a pressure reducer. Table for Fig. 6: Suction times at V1 = 0.5l, pe = 4bar concentration Time Time Time Average [%] Measurement 1 Measurement 2 Measurement 3 [S] 0 90 90 90 90 33 93 93 93 93 66 96 96 96 96 100 (saturated) 99 99 99 99

Also in this case, the suction time increases with increasing concentration of the regenerant solution. The suction times are generally shorter than at 5 since the pumping power of the injector is higher at an inlet pressure of pe = 4bar than at pe = 2 bar due to the higher flow rate of the motive water.

A calibration function can be composed of a multiplicity of calibration characteristics, which for different input pressures pe or propellant pressures p1 were determined. For a determination of the concentration of the regenerant solution at a given inlet pressure pe or motive water pressure p1 then a suitable calibration characteristic can be selected; if necessary, it is also possible to interpolate between closest calibration curves.

The 7 shows in a diagram for experimentally determined suction times (durations t1 ) for sucking off a predefined mass M1 from here 0.5 kg of regenerant solution at various concentrations, expressed in% of the saturation concentration of the regenerant for the same water softening system as in 5 , The inlet pressure pe was set to pe = 2 bar with a pressure reducer. Table for Fig. 7: Suction times at M1 = 0.5kg, pe = 2bar concentration Time Time Time Average [%] Measurement 1 Measurement 2 Measurement 3 [S] 0 127 126 127 126.7 33 122 123 123 122.7 66 120 120 122 120.7 100 (saturated) 117 117 117 117

The absorption times decrease here with increasing concentration of the regenerant solution. For a given mass M1 decreases the volume to be sucked with increasing concentration of the regenerant, since with increasing concentration and the density D of the regenerant solution increases. The course is (nearly) linear, and can (for the mass M1 and the inlet pressure pe = 2 bar) serve as a calibration curve for determining the concentration as a function of the time t1 / suction time.

Note that the suction time is directly proportional to the given mass, so that the suction times which can be taken from the diagram (possibly by extrapolation) can also be converted to masses other than M1 = 0.5 kg, in particular also measured masses.

The 8th illustrates the experimentally determined absorption times (time periods t1 ) for sucking off the predefined mass M1 of 0.5 kg of regenerant solution at various concentrations for the same water softening system as in 5 , Deviating from 7 the inlet pressure pe was set here to a pe = 4 bar with a pressure reducer. Table for Fig. 8: Suction times at M1 = 0.5kg, pe = 4bar concentration Time Time Time Average [%] Measurement 1 Measurement 2 Measurement 3 [S] 0 95 94 95 94.7 33 93 92 92 92.3 66 88 91 90 89.7 100 (saturated) 87 88 88 87.7

Similar to in 7 decreases with increasing concentration of the regenerant solution from the suction time. The suction times are again generally shorter than at 7 since the pumping power of the injector is higher at an inlet pressure of pe = 4bar than at pe = 2 bar due to the higher flow rate of the motive water.

LIST OF REFERENCE NUMBERS

1

Water softening

2

Inlet for raw water

3

Drain for softened water

4

container

4a

softening

5

ion exchange resin

6

supply vessel

7

solid regenerating salt

8th

injector

9

electronic control device

9a

control head

10

Time measuring device

11

display

12

pressure reducer

13

Flowmeter

14

float switch

14a

liquid level

15

upper level (before extraction)

16

lower level (after extraction)

17

Line (line for motive water)

18

Line (suction and refill line)

19

Line (line for dilute regenerant solution C _RM2 )

20

Valve

21

Valve

22

Sequence for regenerant solution

23

sewer

24

regenerating

25

pressure sensor

26

weighing System

27

conductivity sensor

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102010028756 A1 [0002, 0008]
• DE 102015219619 A1 [0010]
• DE 19538617 A1 [0010]
• DE 4313468 A1 [0010]
• DE 4221013 C1 [0010]

Claims (14)

Water softening system (1), comprising - a softening device (4a), in particular comprising at least one container (4) with ion exchange resin (5), - a storage vessel (6) in which a regenerant solution (24) is stored, in particular wherein in the storage vessel ( 6) also contains solid regenerating salt (7), - an injector (8) for transporting regenerant solution (24) from the storage vessel (6) to the softening device (4a), - an electronic control device (9) which is set up to drive in a regeneration operation conveying the regenerant solution (24) from the storage vessel (6) into the softening device (4a), characterized in that the water softening system (1) is adapted, in a conveying step - a volume V1 or a mass M1 conveyed to Regenerant solution (24) to specify or measure (106), - and a time t1 for the promotion of the volume V1 or the mass M1 before (108), and in that the electronic control device (9) is set up with a stored calibration function, in particular comprising one or more stored calibration characteristics, a concentration C _{RM1 of} the delivered regenerant _solution (24) and / or one of the concentration the size of the pumped regenerant solution (24), in particular a salt quantity SM1 contained in the pumped regenerant solution (24), can be determined from V1 or M1 and / or from t1 (116, 118; 140). Water softening system (1) according to Claim 1 , characterized in that the water softening system (1) is adapted to specify for a conveying step a volume V1 or a mass M1 of delivered regenerant solution (24) (106), and a time period t1 for the conveyance of the volume V1 or the mass M1 measure (108), and that the electronic control _device (9) is arranged to determine the concentration C _RM1 and / or the concentration-dependent variable from t1 (116, 118; 140). Water softening system (1) according to Claim 1 or 2 , characterized in that the water softening system (1) comprises a pressure reducer (12), with which a fixed inlet pressure pe is ensured at the injector (8), and that the calibration function for this input pressure pe is determined. Water softening system (1) according to one of Claims 1 or 2 , characterized in that the water softening system (1) comprises a pressure sensor (25) with which a motive water pressure p1 before the injector (8) can be determined, and that the electronic control _device (9) is _adapted to the concentration C _RM1 or from determine the concentration-dependent variable with the calibration function as a function of p1 (116, 118, 140). Water softening system (1) according to one of the preceding claims, characterized in that the water softening system (1) comprises a flow meter (13) with which a motive water volume flow V (t) _TW can be determined directly or indirectly, and in that the electronic control device (9) is set up to determine the concentration C _RM1 or the quantity dependent on the size with the calibration function as a function of V (t) _TW (116, 118, 140). Water softening system (1) according to one of the preceding claims, characterized in that the electronic control device (9) is _adapted to determine a salt amount SM1 contained in the promoted regenerant solution (24) (118), in particular from the concentration C _RM1 and the volume V1 or from the concentration C _RM1 , the mass M1 and a concentration- _dependent density function D (C _RM1 ) of the promoted regenerant _solution (24). Water softening system (1) according to Claim 6 , characterized in that a first setpoint value SW1 for a quantity of salt to be used per regeneration of the softening device (4a) is stored in the electronic control device (9), and in that the electronic control device (9) is set up by SM1 if SW1 is underrun or an undershooting of SW1 by SM1 by more than a threshold - in the ongoing regeneration in a further conveying step to promote an additional volume V2 or an additional mass M2 of regenerant solution (24) from the storage vessel into the softening device (122), - and / or to increase a given volume V1 and / or a predetermined mass M1 and / or a predetermined period of time t1 for subsequent regenerations (124), and / or the duration of a subsequent softening operation compared to a standard duration, which is applied without falling below the setpoint value SW1 would be to shorten (126), and / or in case of exceeding of SW1 by SM1 or exceeding of SW1 by SM1 by more than a threshold value - a given volume V1 and / or a given mass M1 and / or a predetermined time t1 for subsequent regeneration (134). Water softening system (1) according to one of the preceding claims, characterized in that the electronic control device (9) is _adapted to determine a working concentration C _{RM2 of} the dilute regenerant solution in the softening _device (140), in particular from the concentration C _{RM1 of} the pumped regenerant _solution ( 24), a motive water volume flow V (t) _TW and a regenerant solution volumetric flow V (t) _RM . Water softening system (1) according to Claim 8 characterized in that a second set point SW2 for a working _{concentration} C _RM2 of dilute regenerant solution to be used in the regeneration is deposited in the softening device (4a) in the electronic control device (9), and in that the electronic control device (9) is adapted to operate in the If SW2 is exceeded by C _RM2 or if SW2 is exceeded by C _RM2 by more than a threshold - to increase a motive water flow V (t) TW (148), and / or if SW2 is undercut by C _RM2 or _underflow from SW2 through C _RM2 by more than a threshold - to reduce a motive water flow rate V (t) TW (144). Water softening system (1) according to any one of the preceding claims, characterized in that the electronic control _device (9) is _adapted to determine (116) the concentration C _{RM1 of} the delivered regenerant _solution (24) that a third set point SW3 for one in the regeneration to be used concentration C _{RM1 of} the regenerant _solution (24) in the electronic control _device (9) is deposited, and that the electronic control device (9) is _adapted to take corrective action (166), if - a deviation of C _RM1 of SW3 or a deviation of C _RM1 from SW3 has occurred by more than a threshold in a plurality of consecutive feed steps or regenerations, and / or - an average C _RM1 of concentrations C _{RM1 deviates} from several successive feed steps or regenerations from SW3 or by more than a threshold of SW3 deviates, and / or - both a comparison Concentration C _{RM1 comparison of} the regenerant _solution (24), determined by a different method than in Claim 1 described as well as the after Claim 1 certain concentration C _{RM1 deviate} from SW3 or deviate by more than a threshold of SW3. Water softening system (1) according to one of the preceding claims, characterized in that the water softening system (1) comprises means for presetting and / or measuring the volume V1 for a conveying step, in particular a float switch (14) and / or a suction edge and / or an overflow edge the storage vessel (6) and / or one or more flow meters (13). Water softening system (1) according to one of the preceding claims, characterized in that the water softening system (1) comprises means for presetting and / or measuring the mass M1, in particular a weighing device (26) for the storage vessel (6). Water softening system (1) according to one of the preceding claims, characterized in that the water softening system (1) comprises a time measuring device (10) and / or a timer. Water softening system (1) according to one of the preceding claims, characterized in that there is also a conductivity sensor (27) for determining the conductivity of the pumped regenerant solution (24).

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