DE202012102749U1 - Dosing plant for the treatment of water - Google Patents

Abstract

Dosing system (40), comprising - a feed (42) for water to be treated, - a sensor (41) for detecting a water parameter in the inlet (42), - a container or outlet (50) for treated water, - at least one storage container (49; 49a-49c) with water conditioning agent, - at least one metering pump (48; 48a-48b) for metering water conditioning agent from the at least one storage tank (49; 49a-49c) into the water to be treated, - an electronic control device (46) for controlling the metered addition of water conditioning agent to the water to be treated as a function of the water parameter of the water to be treated measured by the sensor (41), a) having in a memory (47) of the electronic control device (46) a plurality of adjoining parameter intervals (21-). 24, 31-33) of possible values of the water parameter of the water to be treated are programmed, b) in a memory (47) of the electron a control device (46) has a plurality of operating modes (25-28; 34-36), wherein different operating modes (25-28, 34-36) provide different dosages of water conditioning agent to the water to be treated, c) the electronic control means (46) is adapted to measure (5) the water parameter of to carry out an allocation of the measured value of the water parameter of the water to be treated to one of the parameter intervals (21-24; 31-33), and an assignment (6) of an operating mode (25-28; 34-36) as a function of assigned parameter interval (21-24; 31-33); d) the electronic control device (46) is designed to operate the dosing system (40) in accordance with the assigned operating mode (25-28, 34-36) (7).

Description

• – einen Zulauf für zu behandelndes Wasser,
• – einen Behälter oder Ablauf für behandeltes Wasser,
• – wenigstens einen Vorratsbehälter mit Wasserkonditionierungsmittel,
• – wenigstens eine Dosierpumpe zum Zudosieren von Wasserkonditionierungsmittel aus dem wenigstens einen Vorratsbehälter in das zu behandelnde Wasser.

The invention relates to a metering system comprising

• An inlet for water to be treated,
• A container or drainage for treated water,
• At least one storage container with water conditioning agent,
• - At least one metering pump for dosing of water conditioning agent from the at least one reservoir into the water to be treated.

In household and industry, often waters with certain properties are required or desired, these properties being achieved by the addition of water conditioning agent. For example, a hardness stabilizer may be added to hard water to reduce limescale in subsequent water installations.

Water conditioning agents are typically added to a water to be treated by means of a metering pump; the amount of conditioning agent added is typically selected depending on the amount of water to be treated.

The EP 2 248 769 A2 discloses a process for purifying wastewater by means of a dosage of chemicals, especially precipitants. With the help of information about the raw water supplied, the wastewater to be treated and / or the treated wastewater, the amount of chemicals to be dosed is calculated. The information used is the water consumption determined with a water meter and, if necessary, the temperature, the pH value, the pressure and information about the wastewater purification result. Detailed details for controlling the dosage are not disclosed.

In the post-published German patent application 10 2011 006 176 It has been proposed to control a dosing system depending on the conductivities of the untreated water and the treated water. The conductivity of the untreated water sets a target value for the difference between the conductivities of the treated and the untreated water. The difference is adjusted to the setpoint via the addition of a water conditioning agent. This allows the dosing to be adapted to a variable water quality.

However, the measured values for the conductivities of the untreated water and the treated water are subject to metrological constant slight fluctuations, whereby a constant readjustment of the dosing of the dosing is effected. This leads to a high degree of wear during the control process of the dosing system. Another disadvantage is that this procedure usually requires two conductivity sensors.

Object of the invention

It is the object of the present invention to present a metering system in which the metering capacity can be adapted to a fluctuating quality of the water to be treated in a simple manner, wherein readjustment processes are reduced.

Brief description of the invention

• – einen Zulauf für zu behandelndes Wasser,
• – einen Sensor für die Erfassung eines Wasserparameters im Zulauf,
• – einen Behälter oder Ablauf für behandeltes Wasser,
• – wenigstens einen Vorratsbehälter mit Wasserkonditionierungsmittel,
• – wenigstens eine Dosierpumpe zum Zudosieren von Wasserkonditionierungsmittel aus dem wenigstens einen Vorratsbehälter in das zu behandelnde Wasser,
• – eine elektronische Steuereinrichtung zum Steuern der Zudosierung von Wasserkonditionierungsmittel zum zu behandelnden Wasser in Abhängigkeit von dem mit dem Sensor gemessenen Wasserparameter des zu behandelnden Wassers, wobei
• a) in einem Speicher der elektronischen Steuereinrichtung mehrere, aneinander anschließende Parameterintervalle möglicher Werte des Wasserparameters des zu behandelnden Wassers programmiert sind,
• b) in einem Speicher der elektronischen Steuereinrichtung mehrere Betriebsmodi programmiert sind, wobei verschiedene Betriebsmodi verschiedene Zudosierungen von Wasserkonditionierungsmittel zum zu behandelnden Wasser vorsehen,
• c) die elektronische Steuereinrichtung dazu ausgebildet ist, eine Messung des Wasserparameters des zu behandelnden Wassers vorzunehmen, eine Zuordnung des gemessenen Werts des Wasserparameters des zu behandelnden Wassers zu einem der Parameterintervalle vorzunehmen, und eine Zuordnung eines Betriebsmodus in Abhängigkeit vom zugeordneten Parameterintervall vorzunehmen;
• d) die elektronische Steuereinrichtung dazu ausgebildet ist, die Dosieranlage gemäß dem zugeordneten Betriebsmodus zu betreiben.

This object is achieved by a metering system comprising

• An inlet for water to be treated,
• A sensor for detecting a water parameter in the inlet,
• A container or drainage for treated water,
• At least one storage container with water conditioning agent,
• At least one metering pump for metering in water conditioning agent from the at least one storage container into the water to be treated,
• An electronic control device for controlling the metered addition of water conditioning agent to the water to be treated in dependence on the water parameter of the water to be treated, measured with the sensor
• a) a plurality of successive parameter intervals of possible values of the water parameter of the water to be treated are programmed in a memory of the electronic control device,
• b) a plurality of operating modes are programmed in a memory of the electronic control device, wherein different operating modes provide different doses of water conditioning agent to the water to be treated,
• c) the electronic control device is designed to carry out a measurement of the water parameter of the water to be treated, to assign the measured value of the water parameter of the water to be treated to one of the parameter intervals, and to assign an operating mode as a function of the assigned parameter interval;
• d) the electronic control device is designed to operate the dosing system according to the associated operating mode.

In the context of the invention, the quality of the water to be treated is monitored via (at least) one sensor, wherein this sensor typically protrudes into the water to be treated or is flushed around by it. The water quality is then categorized using the programmed (predefined) parameter intervals. Depending on the parameter interval (or the predefined quality category) applicable to the measured value of the sensor, an operating mode is then defined. In particular, the mode of operation determines the metered addition of water conditioning agent to the water to be treated, typically in the form of a desired concentration of water conditioning agent in the treated water.

The operating mode or metering is not dependent on the exact value of the water parameter (which typically varies significantly), but only on its affiliation with one of the parameter intervals. The frequency of readjustment processes can then be controlled by the size of the parameter intervals. Larger intervals generally lead to fewer readjustment processes, and smaller intervals generally lead to more readjustment processes. By choosing the interval size significantly wider than the typical fluctuation range of the sensor measured values with unchanged water quality, the frequency of Nachregelprozessen can be effectively limited. Typically, the interval size is one or more, preferably all parameter intervals, at least five times, preferably at least ten times, more preferably at least fifty times the standard deviation of the sensor reading from its mean value with unchanged water quality.

A change in the operating mode and thus a readjustment of the dosing capacity is triggered by the water parameter only in the event of a major change, as a result of which the value of the water parameter falls within a different parameter interval than before. This can reduce wear on the Regelorgangen the dosing.

In the context of the invention, preferably at least three, particularly preferably exactly three or four, successive parameter intervals for the water parameter are set up with different additions of water conditioning agent. Preferably, however, no more than ten, more preferably no more than six consecutive parameter intervals are set up for the water parameter. The same applies to any further water parameters and their further parameter intervals.

A water conditioning agent according to the invention contains one or more chemical substances for water treatment. Typical chemical substances for water treatment here are hardness stabilizers (such as polyphosphates), corrosion inhibitors (such as silicates or ortho-phosphates), precipitants (such as FeSO ₄ , FeCl ₃ or AlSO ₄ ) or hardeners (such as Ca (HCO ₃ ) ₂ solutions) ,

Preferred embodiments of the invention

Particularly preferred is an embodiment of the dosing system according to the invention, in which the electronic control device is designed to automatically repeat step c) on a regular basis and to operate the dosing system according to step d) with the respectively last assigned operating mode. As a result, an automatic adjustment of the dosing to the water quality is established. Preferably, the sensor is read out continuously or at fixed time intervals, typically at a frequency between once every minute and once every week, or at fixed treated amounts of water, typically at a frequency of between every hundred milliliters and every one hundred liters.

Preference is given to an embodiment which provides that the sensor is designed as a conductivity sensor or pH sensor or ion-selective electrode, in particular a Ca-ion-selective electrode, or as a temperature sensor, and the water parameter has a conductivity, a pH, an ion content, in particular Ca. Ion content, or a temperature of the water to be treated. As a rule, conductivity is a good indicator of the hardness and, in general, the corrosion behavior of the water to be treated become. The pH value influences the position of equilibria in the water, in particular the lime-carbonic acid equilibrium, and also directly the corrosion behavior. About the ion-selective electrode can be concluded directly on the calcium content or hardness in the water to be treated (especially if conductivity measurements are not or only inaccurately evaluated, for example, due to previous ion exchange processes). The temperature also affects the location of equilibria, especially the lime-carbonic acid equilibrium, and influences the speed, especially of corrosion processes. If one or more further sensors are also provided or one or more further water parameters are additionally evaluated, these are preferably likewise selected from the options indicated above. In particular, a detection of conductivity and pH or conductivity and temperature is preferred.

Also advantageous is an embodiment in which the dosing comprises a flow meter, especially in the inlet. With this the amount of water to be treated can be determined and thus the dosage can be made more accurate. Alternatively, the metered addition may also take place without explicit determination of the amount of water to be treated, for example by periodically dispensing predefined quantities of conditioning agent independently of water consumption, or by entrainment of conditioning agent depending on the strength of the volume flow of the water to be treated according to the principle of water jet pump.

Also preferred is an embodiment in which according to the programming of the memory of the electronic control device in at least two operating modes, the metered addition of a different amount of an identical water conditioning agent per amount of water to be treated is provided, so that in the at least two operating modes, a different concentration of the identical water conditioning agent is obtained in the treated water. The amount or concentration of the same water conditioning agent can be adapted directly to the water quality. If, due to the value of the water parameter or the associated parameter interval, more or less need for the water conditioning agent is detected, more or less is added accordingly.

Particularly preferred is an embodiment in which the dosing plant comprises a plurality of reservoirs with different water conditioning means. As a result, the individual water conditioning agents can be used more purposefully. In the simplest case, each reservoir contains a different chemical substance for water treatment. Note that in one mode of operation, one or more water conditioning agents may be added.

A preferred development of this embodiment provides that the dosing plant comprises a plurality of reservoirs with mixtures of a plurality of chemical substances for water treatment, wherein the mixing ratios of the chemical substances in the mixtures are different, in particular wherein a separate reservoir is provided for each operating mode. The use of mixtures facilitates the relative dosage of different chemical substances. If a separate mixture is provided in a reservoir for each mode of operation, a fixed absolute ratio of water conditioning agent and water to be treated can be operated, which simplifies the control of the dosing system.

Advantageous is an embodiment in which according to the programming of the memory of the electronic control device within at least one of the operating modes, both the type of or the water conditioning agent, as well as the amount of or the water conditioning agent, which are provided per amount of water to be treated for metering, constant are. This is particularly easy to control; Dose changes within one operating mode are eliminated, which in turn can reduce wear.

In another advantageous embodiment, according to the programming of the memory of the electronic control device, the type of water conditioning agent (s) and / or the amount of water conditioning agent (s) provided per amount of water to be treated are time-varying within at least one of the operating modes , As a result, a different need for water conditioning agent at the beginning of an operating mode can be taken into account compared to later times. For example, ortho-phosphates can be added to the drinking water for protection against corrosion. In this case, a phosphate protective layer is formed on the material to be protected (such as a steel pipe). To build up the protective layer, a larger amount of orthophosphate is needed in the initial phase, while later lower concentrations are sufficient to maintain the protective layer. In order to take account of this effect, for example, in the same operating mode, the metered addition of ortho- Phosphates are halved after treatment of a certain amount of water (about 50 m ³ ) or after a certain time has elapsed since the start of the operating mode (about 6 months).

In a preferred embodiment of the metering system, it is provided that the metering system comprises at least one further sensor for detecting a further water parameter in the inlet, that according to a) in a memory of the electronic control device also several, subsequent, further parameter intervals of possible values of the further water parameter in programmed water are programmed, and that the electronic control device is adapted to c) also measure the other water parameters of the untreated water, make an assignment of the measured value of the further water parameter to one of the other parameter intervals, and the assignment of the operating mode also in dependence from the assigned, further parameter interval. By including (at least) one further water parameter, the adaptation of the dosing capacity to the water quality can be carried out even more precisely.

A preferred embodiment is characterized in that the dosing system further comprises a signal generator, that in an accumulator of the electronic control device, an upper limit and / or a lower limit for the measured water parameter of the water to be treated is stored, and that the electronic control device is adapted thereto to issue an alarm message via the signal generator if the measured value of the water parameter of the water to be treated exceeds the upper limit value and / or if the measured value of the water parameter of the water to be treated falls below the lower limit value. The alarm alerts the user to a significant change in water quality or sensor failure.

Likewise preferred is an embodiment which provides that an upper limit value and / or a lower limit value for the measured water parameter of the water to be treated is stored in a memory of the electronic control device, and that the electronic control device is designed to fit into a predefined standard Change operating mode when the measured value of the water parameter of the water to be treated exceeds the upper limit and / or if the measured value of the water parameter of the water to be treated falls below the lower limit, in particular wherein the standard operating mode an average value of the water parameter to be treated Water from previous measurements, in which the upper limit was not exceeded and the lower limit was not exceeded, corresponds, wherein this average value of the water parameter in a memory of the electronic control device fed hert is. Too high a value for the water parameter is untrustworthy and indicates a sensor defect; the controller then enters the default mode of operation which operates independently of the (untrusted) measurement of the water parameter, preferably taking an average reading. As a result, a better matching dosing performance is usually achieved than with the actual measured value.

Method for operating a dosing system

In the context of the present invention, an above metering unit according to the invention can also be operated in one of the methods shown below; the dosing system (in particular the control unit) is then set up accordingly for carrying out such a method.

• a) Definition von mehreren, aneinander anschließenden Parameterintervallen möglicher Werte des Wasserparameters des zu behandelnden Wassers;
• b) Definition von mehreren Betriebsmodi, wobei verschiedene Betriebsmodi verschiedene Zudosierungen von Wasserkonditionierungsmittel zum zu behandelnden Wasser vorsehen;
• c) Messung des Wasserparameters des zu behandelnden Wassers, Zuordnung des gemessenen Werts des Wasserparameters des zu behandelnden Wassers zu einem der Parameterintervalle, und Zuordnung eines Betriebsmodus in Abhängigkeit vom zugeordneten Parameterintervall;
• d) Betrieb der Dosieranlage gemäß dem zugeordneten Betriebsmodus. Mit diesem Betriebsverfahren ist die Dosierleistung der Dosieranlage an eine veränderte Wasserqualität anpassbar, wobei die Häufigkeit von Nachregelprozessen über die Betriebsmodi bzw. Parameterintervalle reduziert werden kann.

A metering system according to the invention is typically operated with a method, wherein water metering agent is metered into the water to be treated, in particular a stream of water to be treated, so that a treated water is obtained, wherein a water parameter of the water to be treated is determined with a sensor and the dosing system is added to the water to be treated, depending on the determined value of the water parameter water conditioning agent,
with the following steps:

• a) definition of several, consecutive parameter intervals of possible values of the water parameter of the water to be treated;
• b) defining a plurality of modes of operation, wherein different modes of operation provide different dosages of water conditioning agent to the water to be treated;
• c) measuring the water parameter of the water to be treated, assigning the measured value of the water parameter of the water to be treated to one of the parameter intervals, and assigning an operating mode as a function of the assigned parameter interval;
• d) Operation of the dosing system according to the assigned operating mode. With this operating method, the dosing capacity of the dosing system can be adapted to a changed water quality, whereby the frequency of readjustment processes can be reduced via the operating modes or parameter intervals.

Particularly preferred is a variant of this method, in which step c) is repeated regularly and the operation according to step d) takes place with the respectively last assigned operating mode. As a result, an automatic adjustment of the dosing to the water quality is established. Preferably, step c) is repeated at fixed time intervals or after solid treated amounts of water.

Also preferred is a process variant in which in at least two operating modes the metered addition of a different amount of an identical water conditioning agent per amount of water to be treated is provided so that in the at least two modes of operation a different concentration of the identical water conditioning agent in the treated water is obtained. The amount or concentration of the same water conditioning agent can be adapted directly to the water quality.

In an advantageous variant, a metered addition of a first water conditioning agent is provided in at least one first operating mode, and in at least one second operating mode a metered addition of this first water conditioning agent is not provided. The first water conditioning agent is only added when it is really needed.

In a further development of this variant, the metered addition of a second water conditioning agent is provided in the at least one, second operating mode, and in the at least one, first operating mode, a metered addition of this second water conditioning agent is not provided. Also, the second water conditioning agent is added only when it is really needed, with the first and second water conditioning agents each being adapted to different water qualities.

Another preferred variant of the method provides that in at least one operating mode a metered addition of at least two different water conditioning means is provided. The two different water conditioning agents are always kept in different storage containers. With two different water conditioning agents, different properties of the water can be adjusted specifically and independently of each other.

Particularly advantageous is a variant of the method in which, within at least one of the operating modes, both the type of water conditioning agent (s) and the amount of water conditioning agent (s) provided for each metered amount of water to be treated are constant. This is particularly easy to control; Dose changes within one operating mode are eliminated, which in turn can reduce wear. Preferably, all operating modes (temporally) are set up constant.

Also advantageous is a variant of the method in which the nature of the water conditioning agent (s) and / or the amount of water conditioning agent (s) provided for each metered amount of water to be treated are temporally variable within at least one of the operating modes. As a result, a different need for water conditioning agent at the beginning of an operating mode can be taken into account compared to later times.

Particularly preferred is a variant of the method which provides that in step a) also a definition of several, consecutive, further parameter intervals of possible values of at least one further water parameter in the water to be treated takes place, and in step c) also the further water parameter of the untreated water is measured, an assignment of the value of the measured, further water parameter to one of the other parameter intervals, and the assignment of the operating mode also takes place as a function of the associated further parameter interval. By including (at least) one further water parameter, the adaptation of the dosing capacity to the water quality can be carried out even more precisely. When using two water parameters, the conductivity and the pH, or else the conductivity and the temperature of the water to be treated, are preferably determined.

In an advantageous variant of the method, an alarm message occurs when the measured value of the water parameter of the water to be treated exceeds an upper limit and / or if the measured value of the water parameter of the water to be treated falls below a lower limit. The alarm alerts the user to a significant change in water quality or sensor failure.

Likewise preferred is a variant of the method which provides for switching to a predefined standard operating mode if the measured value of the water parameter of the water to be treated exceeds an upper limit and / or if the measured value of the water parameter of the water to be treated falls below a lower limit in particular wherein the standard operating mode corresponds to an average value of the water parameter of the water to be treated from previous measurements in which the upper limit was not exceeded and the lower limit was not exceeded. Too high a value for the water parameter is untrustworthy and indicates a sensor defect; according to the variant, then the standard mode of operation is used, which operates independently of the (untrustworthy) measured value of the water parameter, wherein preferably an average measured value is assumed. As a result, a better matching dosing performance is usually achieved than with the actual measured value.

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.

Detailed description of the invention and drawing

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

1 a flow diagram of a variant of a method for operating a metering system according to the invention;

2 an assignment diagram of a variant of a method for operating a metering system according to the invention;

3 an assignment diagram of another variant of a method for operating a metering system according to the invention;

4 a schematic representation of a first embodiment of a metering system according to the invention, with a conductivity sensor and a reservoir for water conditioning agent;

5 a schematic representation of a second embodiment of a metering system according to the invention, with a conductivity sensor and a pH meter and two storage containers for water conditioning agent, each with its own metering pump;

6 a schematic representation of a third embodiment of a metering system according to the invention, with a conductivity sensor and a thermometer and three reservoirs for water conditioning agent with a common metering pump.

1 Illustrates with a flow chart the basic sequence of a method for operating a metering system according to the invention. As a water parameter, the conductivity of the water to be treated is used as an example; further water parameters are not evaluated in this example.

On the occasion of the start 1 the method is a determination (definition) of conductivity intervals 2 , Then, operating modes are set and assigned to these conductivity intervals 3 , The conductivity intervals and the operating modes (including the mutual assignment) are stored (programmed) in an electronic control device of the dosing system 4 ,

After these preparatory steps (which are usually carried out only once), the conductivity of a water to be treated is measured 5 , The particular conductivity falls within one of the defined conductivity intervals, resulting in an associated operating mode.

This operating mode is selected for the addition of water conditioning agent 6 ; the (here only) metering pump of the metering system is operated according to this operating mode 7 , which is usually given a certain concentration of water conditioning agent in the treated water.

In the following, the conductivity is measured again 8th and verifies the assignment to the previous conductivity interval. If the measured value falls within a different conductivity interval than the previously measured value, cf. exam 9 , will be with the redefinition of the operating mode in step 6 continued. If the affiliation with the previous conductivity interval has not changed, the operation of the dosing pump 7 continue in the same operating mode.

The 2 illustrates the definition and assignment of parameter intervals and operating modes in an example, in which again only the conductivity 20 of the water to be treated (here drinking water) is determined as a water parameter. Further water parameters are not evaluated here. A water conditioning agent (here hardness stabilizer) is used in various concentrations. The general procedure can be as in 1 shown done.

In total there are four conductivity intervals 21 . 22 . 23 . 24 Are defined. The first conductivity interval 21 includes the conductivity values from 0 to less than 250 μS / cm, the second conductivity interval 22 includes the conductivity values from 250 to less than 500 μS / cm, the third conductivity interval 23 includes the conductivity values from 500 to below 750 μS / cm, and the fourth conductivity interval 24 all conductivity values from 750 μS / cm.

Each conductivity interval is exactly one operating mode here 25 . 26 . 27 . 28 assigned. The operating modes 25 - 28 all provide different additions of a hardness stabilizer (here poly-phosphates) before. In the first operating mode 25 , the first conductivity interval 21 no hardness stabilizer is added. In the second operating mode 26 , the second conductivity interval 22 1 mg hardness stabilizer per liter of water to be treated is added. In the third operating mode 27 , which is the third conductivity interval 23 3 mg / l is added, and in the fourth operating mode 28 Finally, 5 mg / l is added. The additions are each time-independent ("constant").

The Drinking Water Ordinance stipulates that phosphates up to a maximum concentration of 5 mg / l (measured as P ₂ O ₅ ) may be added to the drinking water.

The first conductivity interval 21 corresponds to a hardness of the water to be treated from 0 ° dH to 7 ° dH. The very soft water does not require polyphosphates for hardness stabilization. In the second conductivity interval (conductivity range) 22 is a water hardness of 7 ° dH to 14 ° dH. in front. The medium-hard water requires little hardness-stabilizing water conditioning agent. In the third conductivity interval 23 hard water with a hardness of 14 ° dH to 21 ° dH is present. Here, a stronger hardness stabilization is necessary, the concentration of dosed poly-phosphate increases to 3 mg / l. In the fourth conductivity interval (conductivity range) 24 is very hard water with a hardness greater than 21 ° dH. Here, the maximum permissible concentration of 5 mg / l of hardness-stabilizing polyphosphates according to the Drinking Water Ordinance is added. The conductivity of the water to be treated is therefore assigned here to a water hardness; the conductivity intervals thus correspond to hardness ranges.

The method according to the invention ensures in a simple manner that the prescribed limit values of the drinking water ordinance are complied with for each water quality. This is a central requirement of DIN 19635-100 , which serves as a test basis for DVGW certification of dosing systems.

In the above example, an identical water treatment agent is added depending on the operating mode in different concentrations; The dosing can be done easily with the in 4 shown dosing (see below).

Similarly, heating water can also be mixed with anticorrosion agent as a function of the conductivity as a water parameter. The higher the specific conductivity of the heating water to be treated, the more likely the occurrence of corrosion in the heating system. Correspondingly more anticorrosion agent must be added to the heating water. A classification can be made here, for example, as follows: conductivity interval Metered amount of corrosion inhibitor (operating mode) <100 μS / cm low 100 μS / cm to 1000 μS / cm medium > 1000 μS / cm large

3 illustrates the definition and assignment of parameter intervals and operating modes in an example, in which again only the conductivity 20 of the water to be treated (here drinking water) is determined as a water parameter. Further water parameters are not evaluated here. However, several water conditioning agents are used.

The according to the in 3 The dosing system described in the definition and assignment comprises two metering pumps, with the first metering pump metering corrosion-inhibiting ortho-phosphates, while the second metering pump is operated with hardness-stabilizing polyphosphates.

In the first conductivity interval 31 (below 300 μS / cm) soft water is present. Soft water tends very little to form stones, but in soft waters corrosion phenomena can occur in domestic installations, since there is no formation of protective layers on pipe walls. It will therefore be in the first conductivity interval 31 low hardness stabilizing poly-phosphates (concentration 1 mg / l) are used, whereas the concentration of the added corrosion-inhibiting ortho-phosphates is high (3 mg / l). This is in the assigned first operating mode 34 established.

In the third conductivity range 33 (over 500 μS / cm) hard water is present. Formation of stones is pronounced in hard water, but corrosion is of minor importance. The first dosing pump now doses little ortho-phosphate (1 mg / l), while the second dosing pump adds a high concentration of hardness-stabilizing poly-phosphates to the water to be treated (3 mg / l). This is in the assigned third operating mode 36 established.

The second conductivity range 32 covers water of medium hardness (300 to 500 μS / cm). Here, a mean concentration of ortho- and poly-phosphates (2 mg / l each) is used for water conditioning. This is in the assigned second operating mode 35 established.

The added total phosphate concentration is in all three conductivity ranges 31 . 32 . 33 at 4 mg / l.

In a variant of this example, even with soft water, the administration of hardness-stabilizing polyphosphates can be completely dispensed with, and in the case of hard water, the administration of corrosion-inhibiting ortho-phosphates can be completely dispensed with, as explained in the following table: conductivity interval water hardness problem Water conditioning agent (operating mode) <300 μS / cm soft corrosion ortho-phosphates 300 μS / cm to 500 μS / cm medium Corrosion and stone formation ortho- and poly-phosphates > 500 μS / cm hard stone formation poly-phosphates

In the context of the invention, it is also possible to use a plurality of water parameters for determining the operating mode via associated parameter intervals. Accordingly, the assignment to the operating modes then becomes multidimensional.

Monitoring of several water parameters

The following table illustrates an example in which the conductivity and pH of the water to be treated are monitored as water parameters; At the crossing points of the table, an operating mode for the associated parameter intervals is defined in each case. This example can be used with the dosing system of 5 be realized (see below). pH <8.2 8.2 ≤ pH ≤ 8.5 pH> 8.5 Conductivity <100 μS / cm low concentration of corrosion inhibitor, additional buffer low concentration of corrosion inhibitor, no buffer low concentration of corrosion inhibitor, additional buffer 100 μS ≤ conductivity ≤ 1000 μS / cm medium concentration of anticorrosive, additional buffer average concentration of corrosion inhibitor, no buffer medium concentration of anticorrosive, additional buffer Conductivity> 1000 μS / cm high concentration of corrosion inhibitor, additional buffer high concentration of corrosion inhibitor, no buffer high concentration of corrosion inhibitor, additional buffer

Water treatment aims to reduce the risk of corrosion in a heating circuit in which aluminum-containing materials and other materials (steel, copper) are installed. Aluminum-containing materials corrode at pH values above 8.5, while for the resistance of other materials in heating systems such as steel and copper, a pH in the alkaline range above 8.2 is favorable. By adding buffer, the pH in the treated water can be converted to a desired pH range between 8.2 and 8.5. Depending on the conductivity, corrosion inhibitor is added.

It should be noted that equal additions of water treatment agents are provided in each case for the same conductivity for low pH values (below 8.2) and high pH values (above 8.5). H. the operating modes are in so much the same.

dosing

The 4 schematically shows an embodiment of a metering system according to the invention 40 , in which the conductivity of the water to be treated as a water parameter with a sensor 41 namely, a conductivity sensor 41a , is recorded.

The water to be treated flows through an inlet 42 to, being the inlet 42 with a shut-off valve 43 can be closed (note that the inlet 42 to the metering pump 48 enough). A check valve 44 prevents backflow against the normal inflow direction. The incoming water to be treated will continue to flow with a flow meter 45 followed quantitatively.

In an electronic control device 46 are in a store 47 Definitions of parameter intervals of electrical conductivity, various operating modes and their assignments stored. The electronic control device 46 evaluates the signals of the sensor 41 out (ie determines the conductivity LF of the water to be treated) and assigns the associated operating mode.

According to this operating mode, the metering pump 48 from the controller 46 driven, from a reservoir 49 promotes a water conditioning agent. The flow rate is chosen so that, taking into account the amount of water flowing through, with the flow meter 45 is determined, a mode of operation corresponding concentration of the water conditioning agent in the treated water behind the metering pump 48 results. The treated water flows through a drain 50 from (note that the expiration 50 behind the dosing pump 48 starts).

For information of the user is at the electronic control device 46 an ad 51 which outputs the current measured conductivity (in this case 735 μS / cm) as well as the currently valid operating mode (here q "M1"). By means of a signal generator 53 (here a light signal) can be an exceptional conductivity reading (for example, above 2000 μS / cm or below 50 μS / cm, the limits are in the memory 47 filed) are signaled; such an extraordinary reading indicates a defect in the sensor 41 out. The control device 46 With such an exceptional reading, it will switch to a standard mode of operation as if a predefined average or past conductivity average conductivity value (eg, 400 μS / cm) had been measured.

In 5 is a second embodiment of a dosing system according to the invention 40 shown schematically. The essential differences from the embodiment of FIG 4 explained.

The dosing system 40 includes two sensors 41 namely, a conductivity sensor 41a and a pH electrode 41b to check the quality of the water to be treated; the signals of the sensors 41 in turn are from the electronic control device 46 evaluated. This one has in her store 47 Definitions of parameter intervals are stored (programmed) both for the electrical conductivity and for the pH value, and the assignment of an operating mode takes place taking into account the membership of the parameter interval belonging to the current conductivity value and the further parameter interval belonging to the current pH value. The ad 51 Here you can see the current conductivity, the current pH value and the valid operating mode.

The control device 46 controls two dosing pumps here 48a . 48b on, each with its own storage containers 49a . 49b associated with various water conditioning agents. This allows the controller 46 Add the two water conditioning agents independently of each other. For example, one of the reservoir contains 49a a corrosion inhibitor, and the other reservoir a buffer solution.

6 schematically shows a third embodiment of a metering system according to the invention 40 ; Again, only the essential differences from the previous embodiments will be explained.

The dosing system 40 here includes two sensors 41 namely, a conductivity sensor 41a and a temperature sensor 41c to determine the quality of the water to be treated. The signals of the sensors 41 are sent to the electronic control device 46 forwarded. The memory 47 the control device 46 contains definitions of parameter intervals both for the conductivity LF and for the temperature T, and the assignment of an operating mode takes place taking into account the membership of the parameter interval belonging to the current conductivity value and the further parameter interval belonging to the current water temperature. The ad 51 Here you can see the current conductivity, the current temperature and the valid operating mode.

The control device 46 controls a dosing pump here 48 and a motor switchable valve 52 at. With the valve 52 can be one of three storage containers 49a . 49b . 49c be selected from which the metering pump 48 Aspirates water conditioning agent and promotes into the water to be treated. The flow rate is at the instantaneous water flow, as with the flow meter 45 is determined, adjusted so that a desired, corresponding to the current operating mode concentration of the water-conditioning agent in the treated water results.

The three storage tanks 49a . 49b . 49c contain here in each case different mixtures of ortho-phosphates and poly-phosphates.

In the first storage container 49a here is a conditioner containing 3 mg of an orthophosphate and 10 mg of a polyphosphate per 1 ml of solution; This conditioner is used for soft water.

In the second Vorrastbehälter 49b a conditioner containing 2 mg of an orthophosphate and 20 mg of a polyphosphate per 1 ml of solution; This conditioner is used for medium-hard water.

In the third Vorrastbehälter 49c a conditioner containing 1 mg of an orthophosphate and 30 mg of a polyphosphate per 1 ml of solution; This conditioner is used for hard water.

When accessing each of the reservoir 49a . 49b . 49c At temperatures below 10 ° C, a concentration of 0.05 ml solution per liter of water to be treated is added. At temperatures between 10 ° C and 30 ° C 0.10 ml of solution per liter of water to be treated are added, and at temperatures above 30 ° C 0.15 ml of solution per liter of water to be treated are added. The higher concentrations of water conditioning agent at higher temperatures can compensate for the higher corrosion rate and higher rate of lime deposition at higher temperatures.

In summary, the invention describes a dosing system with which the water quality of the water to be treated is monitored by means of at least one water parameter. At least one sensor, in particular a conductivity sensor, is used for this monitoring. An operating mode, which determines the delivery rate of at least one dosing pump for a water conditioning agent, is determined by the Affiliation of a measured value of the water parameter to one of several parameter intervals. As a result, the control effort of the dosing can be reduced.

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

• EP 2248769 A2 [0004]
• DE 102011006176 [0005]

Cited non-patent literature

• DIN 19635-100 [0055]

Claims (12)

Dosing system ( 40 ), comprising - a feed ( 42 ) for the water to be treated, - a sensor ( 41 ) for the acquisition of a water parameter in the inlet ( 42 ), - a container or drain ( 50 ) for treated water, - at least one storage container ( 49 ; 49a - 49c ) with water conditioning agent, - at least one metering pump ( 48 ; 48a - 48b ) for metering in water conditioning agent from the at least one storage container ( 49 ; 49a - 49c ) into the water to be treated, - an electronic control device ( 46 ) for controlling the metering of water conditioning agent to the water to be treated in dependence on that with the sensor ( 41 ) measured water parameters of the water to be treated, a) in a memory ( 47 ) of the electronic control device ( 46 ) several, adjoining parameter intervals ( 21 - 24 ; 31 - 33 ) of possible values of the water parameter of the water to be treated are programmed, b) in a memory ( 47 ) of the electronic control device ( 46 ) several operating modes ( 25 - 28 ; 34 - 36 ) are programmed, with different operating modes ( 25 - 28 ; 34 - 36 ) provide various doses of water conditioning agent to the water to be treated, c) the electronic control device ( 46 ) is adapted to measure ( 5 ) of the water parameter of the water to be treated, an assignment of the measured value of the water parameter of the water to be treated to one of the parameter intervals ( 21 - 24 ; 31 - 33 ) and an assignment ( 6 ) of an operating mode ( 25 - 28 ; 34 - 36 ) depending on the assigned parameter interval ( 21 - 24 ; 31 - 33 ); d) the electronic control device ( 46 ) is adapted to the dosing system ( 40 ) according to the assigned operating mode ( 25 - 28 ; 34 - 36 ) to operate ( 7 ). Dosing system ( 40 ) according to claim 1, characterized in that the electronic control device ( 46 ) is adapted to automatically repeat step c) on a regular basis and the dosing system ( 40 ) according to step d) with the respectively last assigned operating mode ( 25 - 28 ; 34 - 36 ) to operate ( 7 ). Dosing system ( 40 ) according to claim 1 or 2, characterized in that the sensor ( 41 ) as a conductivity sensor ( 41a ) or pH sensor ( 41b ) or ion-selective electrode, in particular Ca-ion-selective electrode, or as a temperature sensor ( 41c ), and the water parameter has a conductivity ( 20 ; LF), a pH, an ion content, in particular Ca ion content, or a temperature (T) of the water to be treated. Dosing system ( 40 ) according to one of the preceding claims, characterized in that the dosing system ( 40 ) a flow meter ( 45 ), especially in the inflow ( 42 ). Dosing system ( 40 ) according to one of the preceding claims, characterized in that according to the programming of the memory ( 47 ) of the electronic control device ( 46 ) in at least two modes of operation ( 25 - 28 ; 34 - 36 ) the metered addition of a different amount of an identical water conditioning agent per amount of water to be treated is provided, so that in the at least two operating modes ( 25 - 28 ; 34 - 36 ) a different concentration of the identical water conditioning agent in the treated water is obtained. Dosing system ( 40 ) according to one of the preceding claims, characterized in that the dosing system ( 40 ) several storage containers ( 49 ; 49a - 49c ) with different water conditioning agents. Dosing system ( 40 ) according to claim 6, characterized in that the dosing system ( 40 ) several storage containers ( 49 ; 49a - 49c ) comprising mixtures of a plurality of chemical substances for water treatment, wherein the mixing ratios of the chemical substances in the mixtures are different, in particular wherein for each operating mode ( 25 - 28 ; 34 - 36 ) own reservoir ( 49 ; 49a - 49c ) is provided. Dosing system ( 40 ) according to one of the preceding claims, characterized in that according to the programming of the memory ( 47 ) of the electronic control device ( 46 ) within at least one of the operating modes ( 25 - 28 ; 34 - 36 ) both the type of water conditioning agent (s) and the quantity the one or more water conditioning agent, which are provided for each amount of the water to be treated for metering, are constant. Dosing system ( 40 ) according to one of the preceding claims, characterized in that according to the programming of the memory ( 47 ) of the electronic control device ( 46 ) the type of water conditioning agent (s) and / or the amount of water conditioning agent (s) intended to be metered per amount of water to be treated within at least one of the operating modes ( 25 - 28 ; 34 - 36 ) are temporally variable. Dosing system ( 40 ) according to one of the preceding claims, characterized in that the dosing system ( 40 ) at least one further sensor ( 41 ) for detecting a further water parameter in the inlet, that according to a) in a memory ( 47 ) of the electronic control device ( 46 ), several, successive, further parameter intervals of possible values of the further water parameter in the water to be treated are programmed, and in that the electronic control device ( 46 ) is adapted, in accordance with c), also to measure the further water parameter of the untreated water, to assign the measured value of the further water parameter to one of the further parameter intervals, and to assign ( 6 ) of the operating mode ( 25 - 28 ; 34 - 36 ) also in dependence on the assigned, further parameter interval. Dosing system ( 40 ) according to one of the preceding claims, characterized in that the dosing system ( 40 ), a signal generator ( 53 ) that in a memory ( 47 ) of the electronic control device ( 46 ) an upper limit value and / or a lower limit value for the measured water parameter of the water to be treated is stored, and in that the electronic control device ( 46 ) is adapted, via the signal transmitter ( 53 ) to issue an alarm message if the measured value of the water parameter of the water to be treated exceeds the upper limit value and / or if the measured value of the water parameter of the water to be treated falls below the lower limit value. Dosing system ( 40 ) according to one of the preceding claims, characterized in that in a memory ( 47 ) of the electronic control device ( 46 ) an upper limit value and / or a lower limit value for the measured water parameter of the water to be treated is stored, and in that the electronic control device ( 46 ) is adapted to change to a predefined standard operating mode if the measured value of the water parameter of the water to be treated exceeds the upper limit and / or if the measured value of the water parameter of the water to be treated falls below the lower limit, in particular wherein the standard Operating mode an average value of the water parameter of the water to be treated from previous measurements in which the upper limit was not exceeded and the lower limit was not exceeded, this average value of the water parameter in a memory ( 47 ) of the electronic control device ( 46 ) is stored.

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