EP1844301A2

EP1844301A2 - Method for transporting and detecting a transported quantity of a liquid containing gas and corresponding device

Info

Publication number: EP1844301A2
Application number: EP06706176A
Authority: EP
Inventors: Alfred Böhm
Original assignee: Bartec GmbH
Current assignee: Bartec GmbH
Priority date: 2005-02-04
Filing date: 2006-01-09
Publication date: 2007-10-17
Also published as: CA2594500A1; WO2006081911A2; WO2006081911A3

Abstract

The invention relates to a method for detecting the quantity of transported gas-containing liquid consisting in transferring said gas-containing liquid through a conduit from a first pick-up position to a second pick-up position and in measuring a flow rate and a filling degree in said conduit. A device for detecting quantity during a liquid reception and/or delivering is also disclosed.

Description

Method for conveying and for measuring quantity of a liquid and device for quantity detection when accepting and / or dispensing a liquid

The invention relates to a method for conveying a liquid comprising a gas fraction from a first delivery location to a second delivery location and to the delivery quantity detection. The invention further relates to a device for quantity detection in the acceptance and / or delivery of a liquid.

When accepting and dispensing liquids, in particular from a stationary tank into a mobile tank or vice versa, a volume measurement is usually required in custody transfer. The volume of the flowing product can be determined, for example, from a measurement of the flow and its integration over time. However, it can be problematic with this measurement that the flowing product, for example milk, wine or heating oil, more or less strongly, in particular at the beginning and / or at the end of the acceptance or delivery, but also when changing from one tank to another tank may be laden with air or possibly also with another gas. This gas loading can lead to a measurement error if the gas is measured as a liquid during flow measurement.

The problem of gas loading can occur in particular in measurements on milk collection trucks and / or on fuel oil vehicles. In order to reduce Fehlnαessungen due to the gas loading, it is known to use so-called gas separators or Gasmessverhüter. Such devices are described, for example, in the article "Gas Separating Devices" by H. -H . Oelze, published in the report of the Physikalisch-Technische Bundesanstalt "Volume and mass measurements of liquids", M. Zander (ed.), ISBN 3 -88314-741-9, Dec. 1987, known.

Gas meters and gas separators are usually complex mechanical structures. They are often relatively heavy, whereby the maximum weight of a mobile tank can be reduced. In addition, both their acquisition costs and their operating costs are relatively high, especially since a comparatively high cleaning effort is usually required. In addition, they can also limit the acceptance and / or the delivery rate, since the degassing of the product can not be performed in principle in any short time.

From DE 197 10 296 Cl it is known to divide the delivery flow into a main and a secondary flow, and to free the secondary flow by means of a separator of air admixtures. Ultrasonic running time measurements in the main and in the secondary flow are used to determine the gas content in the main stream. The method of DE 197 10 296 C1, however, is comparatively complicated due to its flow guidance and the required double measurement. In addition, a complex and heavy gas separator is still required for the secondary flow.

From WO98 / 11429 a method and a device are known, with which the acceptance performance of a measuring system for milk to be optimized when using the known Luftabscheidesysteme. This document teaches, for example, to determine the air charge of the milk flow by measuring transit time and to control the intake capacity as a function of the determined air charge. It is assumed that a significant air load usually only too Beginning and end of the milk takeover occurs, while in the intermediate main stream there is no appreciable air charge and thus no reduction in the intake capacity is required. For small delivery quantities, in which the beginning and end of the milk intake already follow each other directly, the aforementioned method is, however, only of limited suitability since it is necessary to work almost continuously with a reduced intake capacity. Moreover, since gas loading may occur even during the main flow, for example in the case of leaky connecting elements, in particular hose couplings, unwanted time losses may result in the previously known method even with large delivery quantities.

From DE 198 39 112 A1, DE 100 17 379 A1 and DE 100 46 921 C1 dipstick measuring methods are known with which the problem of incorrect measurements in gas loading can be circumvented. Since, however, each tank to be filled or emptied usually has to have at least one own dipstick measuring device, and since, as a rule, each tank must be measured with respect to its volume by a legal calibration, the previously known dipstick be comparatively expensive.

A object of the invention is to provide a method for conveying and delivery quantity detection of a gas portion aufwei send liquid from a first delivery to a second delivery and a device for quantity detection in the acceptance and / or delivery of a liquid, the high accuracy of a particularly simple , allow fast and economical transfer of liquid.

The object is achieved by a method having the features of claim 1 and an apparatus having the features of claim 12. Preferred embodiments are given in the dependent claims. A first aspect of the invention resides in a method for delivery and delivery quantity detection of a gas-containing liquid, in particular milk or fuel, from a first supply location to a second supply location, in which the liquid with the gas portion is transferred from the first supply location into a line , the liquid is passed through with the gas portion through the line, in the line a degree of filling is performed, in the line a flow measurement is performed, the liquid is transferred together with the gas content contained therein from the line to the second place of delivery and the results of flow measurement with those of the degree of filling measurement are calculated to determine the delivery rate.

A basic idea of the invention can be seen in the fact that gas bubbles, which are located in the medium to be transported and measured, are not rejected or excreted, but are measured and included in the flow rate determination. For this purpose, a filling degree measurement is provided with which the gas content, in particular the gas bubble content, of the liquid present in the line can be determined.

Accordingly advantageously eliminates a gas separation in the liquid transfer between the two stations. Accordingly, a previously customary air separator or Gasmessverhüter omitted. This requires a reduction in the cost, in particular due to a reduced maintenance costs, as well as a reduction in the weight of the device used to carry out the method. Especially with mobile devices, this weight reduction can lead to an increase in the weight of the load. In addition, results in the inventive method, compared to previously known methods with gas separators, a reduction of the flow resistance in the line, resulting in an increase in the suction / pumping power or. a reduction of the pumping effort follows. Furthermore, the invention allows a simplification of the Verrohrungsaufwandes and a particularly simple Cleaning the device, in particular with a cleaning-in-place method (CIP method). Also, the device used for the method according to the invention can be designed particularly tamper-proof. Finally, the method according to the invention also allows a comparatively high measuring accuracy. In experiments, a relative error, i. H . a calibration accuracy of approx. 0, 3% or better in determining the flow rate can be achieved. The method according to the invention and the device according to the invention are basically suitable for any delivery quantities, but also for large delivery quantities.

The degree of filling may, for example, be understood as meaning the liquid content and / or the liquid level in the line, but also the gas content, in particular the content of undissolved gas, in the liquid. For Füllgradmessung may be provided on the line a Füllgradmesseinrichtung, which may be formed in particular as a bubble detector. The degree of filling measuring device can preferably be designed as a conductivity sensor, as a capacitive sensor and / or as an optical sensor. The filling degree measurement can accordingly be understood in particular to be a conductivity measurement, a capacitive measurement and / or an optical measurement of the degree of filling. A conductivity measurement is particularly suitable for conductive liquids, such as milk, while ei ne capacitive or optical measurement, especially in non-conductive fluids, such as fuel oil, is preferred.

In the flow measurement, in particular a volume flow and / or a mass flow through the line can be detected. For flow measurement, a flow meter is suitably used. This flow measuring device can, for example, as a volume counter, in particular as a volumetric counter, d. H . as a directly measuring volume meter, and / or as a flow meter, d. H . be designed as indirectly metering volume counter. In particular, a displacement meter, an outlet counter, a measuring wing, a throttle device and / or a Coriolis counter. A particularly reliable and accurate flow measurement can be obtained with a magnetic inductive counter.

Since flow measurements, in particular also with the Coriolis measuring method, are generally impaired by the influence of gas loadings, according to the invention a filling degree measurement is provided by means of which these impairments can be compensated for in determining the delivery quantity. According to the invention, the filling degree measurement and / or the flow measurement can in principle serve to determine any measured variables correlated with the degree of filling or the flow, ie also for indirect measurement.

It is particularly preferred that the degree of filling measuring device for filling degree measurement and / or the flow measuring device for flow measurement is designed as described in EP 0 617 789 B1, EP 0 626 567 A1 and / or as described in the German utility model application with the file reference 20 2004 019 442.2 , Thus, the degree of filling measuring device may in particular be formed with a measuring chamber wall surrounding a measuring chamber, in which at least one opening for introducing and / or discharging the liquid is provided, and at least two planar electrodes, which are arranged opposite one another in the region of the measuring chamber wall in the measuring chamber the measuring chamber wall in isolation areas, which connect to the two electrodes and surround them flat, is designed to be electrically insulating.

The method according to the invention can be used, in particular, in the acceptance and / or discharge of liquid substances, preferably from stationary tanks into mobile tanks and / or vice versa, for example in goods traffic subject to custody. In principle, the invention is suitable for any liquids, but preferably for milk, dairy products, wine or fuel, in particular fuel oil. In particular, at least one of the preparation sites may be located on a collecting trolley, in particular on a milk collecting trolley or on a heating oil tanker. vehicle, be provided. Preferably, the method according to the invention is used for quantity acquisition in liquid intake, in particular milk intake, with a mobile or stationary acceptance system.

For calculating the measurement results and for determining the delivery rate, an evaluation device is suitably provided, with which the filling degree measuring device and the flow measuring device are in signal connection. This preferably has an electronic computer.

In principle, any measuring methods can be used for filling degree measurement and / or flow measurement. However, it is particularly preferred that a conductivity measurement and / or a capacitance measurement is carried out for filling degree measurement and / or that a flow rate measurement, in particular a magnetic-inductive measurement, is carried out for flow measurement. As a result, a high accuracy can be achieved with high reliability.

It is further particularly preferred that the liquid is passed continuously through the conduit. The degree of filling measurement and / or the flow measurement can also be carried out continuously, or at least repeatedly. In particular, it may be provided to vary the delivery rate of the liquid over time, which may be done depending on the characteristics of the medium in the line, preferably depending on the filling level.

To further increase the measurement accuracy can be provided that in the line, in particular in the region of a measuring point for the degree of filling, a pressure measurement is performed. For this purpose, at least one pressure measuring device is suitably provided on the line. The pressure measurement is based on the idea that gas resp. Gas bubbles in contrast to the liquid is highly compressible. Consequently, the measured fill level can be dependent on the current pressure. The results of the pressure measurement can be used to determine the flow rate with the result the flow measurement and the results of the filling degree measurement. For this purpose, the at least one pressure measuring device is suitably in signal communication with the evaluation device. A pressure measurement can also be carried out, for example, in the region of a measuring point for flow measurement. Basically, the pressure measurement can be performed on any line areas, with a pressure measurement at several points is possible.

In principle, it is possible according to the invention to pass the liquid through the line, for example, by gravity. However, it is particularly preferred that the liquid is pumped through the line by means of a feed pump arranged on the line. The feed pump can be designed for example as a centrifugal pump.

It is further preferred that a pressure measurement be performed in the conduit both upstream and downstream of the feed pump. As a result, the measurement accuracy can be further increased.

In principle, the filling degree measurement and the flow measurement can be carried out at any measuring points in the piping system. A particularly simple procedure with high measurement accuracy can be given by the fact that the filling degree measurement and the conductivity measurement are carried out at the same measuring point. For this purpose, the Füllgrad- measuring device and the flow measuring device can be combined and in particular have a common electrode pair, which can serve for example both for conductivity measurement and for magnetic-inductive flow measurement. With regard to the feed pump, the degree of filling measuring device and the flow measuring device can basically be arranged as desired. They can be arranged, for example, with regard to the feed pump on the same line side, but also on different line sides. If the filling degree measuring device and the flow measuring device are arranged on the same line side with respect to the feed pump, Either the filling degree measuring device or the flow measuring device can be arranged on the line closer to the feed pump.

It is particularly advantageous that the filling degree measurement is carried out in particular upstream from the feed pump and that the pumping capacity of the feed pump is set to be filling level-dependent. In this case, the Füllgradmess- device is used to control the pump. For this purpose, a control device is suitably provided, which is in signal communication both with the feed pump and with the Füllgrademesseinrichtung. The fill level-dependent setting makes it possible, in particular, to reduce the pumping capacity of the feed pump with increasing proportion of gas, for example when the limit value is exceeded. To set the pump power, alternatively or additionally to the degree of filling measuring device, at least one further degree of filling measuring device can be provided, which can also be combined with a temperature sensor.

A further advantageous embodiment of the invention consists in that at least one of the preparation locations is arranged in a container which is preferably designed to be mobile. Preferably, both supply locations are in each case arranged in another container. The at least one container can be designed as a tank.

A self-priming promotion can be given according to the invention in that for sucking the liquid into the line at least temporarily a negative pressure in the line is generated. For this purpose, for example, an ej ector or a vacuum pump can be provided. A negative pressure can be generated, in particular, when the delivery rate of the pumping device drops or breaks off due to excessively high proportions of gas, which may be the case in particular at the beginning or at the end of the delivery.

The measuring accuracy can be further increased by the fact that the liquid for the uniform distribution of the gas fraction upstream. the measuring point for the degree of filling is passed through a sieve arranged in the cross section of the line. In this way, a particularly uniform distribution of gas bubbles over the flow cross section of the line can be generated, which allows a particularly accurate degree of filling measurement. Alternatively or in addition to the screen, a filter, a grid and / or a p.c. rectifier may be provided.

To increase the delivery rate can be provided that a before the promotion of the liquid in the line ent held gas column is derived via a vent line from the line. For this purpose, a vent valve can be provided on the vent line, which is switched in response to a level in the vent line. Suitably, the vent line is arranged on a housing of the feed pump.

To further increase the accuracy of measurement, it may be provided, preferably at the beginning of the delivery, to flood the filling degree measuring device and to temporarily generate a flow stop in the filling degree measuring device. For this purpose, for example, the feed pump can be taken out of service and / or the line by means of valves downstream of the Füllgradmesseinrichtung be blocked for a fluid passage. This makes it possible to calibrate the degree of filling measuring device, in particular at the beginning of the conveyance with the liquid flowing. In particular, the liquid can be left while the flow is in the Füllgradmesseinrichtung until the gas fraction is separated and / or leaked from the Füllgradmesseinrichtung in remaining line areas.

A further aspect of the invention resides in a device for quantity detection when accepting and / or dispensing a liquid, preferably milk or fuel, with at least one container for receiving the liquid, a line which at its one end communicates with the container in flow mode. Connection and having at its other end a flow opening for the liquid, a line arranged on the pump for pumping the liquid through the line, a Füllgradmesseinrichtung, which is arranged on the line, a flow measuring device, which is arranged on the line, and an evaluation device for determining the amount of liquid delivered, which is in signal communication with the degree of filling measuring device and the flow measuring device.

The device according to the invention is particularly suitable for carrying out the method according to the invention, whereby the advantages explained in this connection can be achieved. The device according to the invention can be embodied in particular as described in connection with the method. Volume detection may preferably be understood to mean volume detection. Advantageously, the flow opening is provided on a receiving coupling of the line.

A particularly low flow resistance and thus a particularly high flow rate can be achieved according to the invention in that the line, at least outside the feed pump, the Füllgradmesseinrichtung and / or the flow measuring device, an at least approximately constant line cross-section. Advantageously, the line, at least outside the feed pump, the Füllgradmesseinrichtung and / or the flow measuring device, designed for an approximately linear flow, d. H. in particular for a flow direction running along the conduit wall assuming an ideal laminar flow. The line is preferably formed without gas separator and without Gasmessverhüter.

The device according to the invention can also be referred to as a measuring system for milk and other liquid products which are laden with air. The invention will be explained in more detail with reference to preferred embodiments, which are shown schematically in the figures. In the figures show:

Fig. 1 . to 6 different embodiments according to the invention

Devices in carrying out the method according to the invention.

Like-acting elements are indicated in the figures throughout with the same reference numerals.

A first embodiment of a device according to the invention is shown in FIG. 1 shown. The illustrated apparatus serves to convey a liquid from a first supply location 1 to a second supply location 2. The first supply location 1 is arranged in a first container 31 designed as a tank and the second supply location 2 in a second container 32 likewise designed as a tank The second container 32 can be considered as part of the device according to the invention. In particular, like the entire device according to the invention, it can be provided on a tanker and / or a collection truck on a mobile basis.

The device has a conduit 10 which is fixedly arranged on the container 32 designed as a container. In line 10, a feed pump 20 is arranged, which is designed as a centrifugal pump. Between the feed pump 20 and the collecting container 32, a filling degree measuring device 5 and a flow measuring device 6 are arranged on the line 10. The degree of filling measuring device 5 is arranged closer to the feed pump 20 in the illustrated embodiment than the flow measuring device 6. In principle, but is also a reverse arrangement is possible in which the flow measuring device 6 is closer to the feed pump. The flow measuring device 6 and the degree of filling measuring device 5 can also be combined in a common device.

Above the feed pump 20, a vent line 40 is provided which is in fluid communication with the line 10. At this vent line 40, a vent valve 42 and above a level measuring device 45 are arranged. Between the second container 32 and the feed pump 20, a check valve 16 is disposed in the conduit 10. In the illustrated embodiment, the check valve 16 between the Fδrderpumpe 20 and the Füllgradmesseinrichtung 5 and the flow meter 6 is arranged.

At its end facing away from the collecting container 32, the line 10 has a flow opening 12, on which the line 10 is flanged by means of a receiving coupling 15 releasably attached to the first container 31. The flow opening 12 may also be referred to as inlet and / or outlet opening. On the line 10, in the illustrated embodiment, between the flow opening 12 and the feed pump 20, a temperature sensor 23 is provided. By means of the temperature sensor 23, temperature measurements can be carried out on the conveyed liquid, which can be used for quality control and / or compensation calculations, for example for conversion to a standard volume.

The temperature sensor 23 can also be designed as a combined temperature-Füllgradsensor, in particular as a combined temperature-conductivity sensor. In this case, the temperature-level sensor can be used for control functions for the derpumpe 20 are used. This makes it possible to regulate the pump power in the event of coarse air blows. A fine control of the pump can be carried out on the basis of the measured values of the fill level measuring device 5, which can also be referred to as an air bubble sensor.

A connection of the line 10 with the tank 31, as shown in FIG. 1, by a rigid pipe section 71 and / or, as shown in FIG. 2, carried by a flexible hose 72. As shown in FIG. 2, an acceptance valve 14 can be provided on the line 10 on the side of the acceptance coupling 15.

The device according to the invention can serve for the measured delivery of liquid, in particular milk, from the first container 31, which can also be referred to as a delivery tank, into the second container 32, which can also be referred to as a destination tank. The device can be arranged so that the assumption clutch 15 and in particular also the feed pump 20, as shown in FIG. 2, are arranged deeper than the first container 31, so that the liquid can flow to the feed pump 20 by gravity.

At the beginning of the promotion, the vent valve 42 and the acceptance valve 14 are opened. As a result, the product may flow from the first container 31 to the feed pump 20, whereby a gas column contained in the line 10 before the product is discharged via the vent line 40. In this way, a system ventilation can be realized, which is particularly advantageous when the feed pump 20 is designed as a non-self-priming pump, for example as a centrifugal pump. The vent allows reliable operation of the feed pump 20 with high efficiency. W 2

15

The successful system ventilation can be detected by means of the level measuring device 45. As soon as this filling level measuring device 45 reports wetting, the venting valve 42 can be closed.

Now the feed pump 20 can be put into operation. As a result, a pressure builds up, which opens the check valve 16. The liquid passes from the feed pump 20 into the Füllgradmesseinrichtung 5, which measures the proportion of gas in the product to be measured, and can also be referred to as air flow meter. From here, the complete liquid flow, together with the gas component, reaches the flow measuring device 6, which can be designed as a volumetric meter. From the flow measuring device 6, the liquid finally reaches the second container 32 together with the gas fraction contained therein.

If the line 10 is formed in the Füllgradmesseinrichtung 5 and the flow measuring device 6 with the same cross section, the speed in the liquid column at the measuring devices 5 and 6 at least approximately the same size. This can be achieved, in particular, when the degree of filling measuring device 5 is embodied as a conductivity measuring device and the flow measuring device 6 as a magneto-inductive measuring device.

By means of the degree of filling measuring device 5, alternatively or additionally, however, also by means of the temperature sensor 23 designed as a combined temperature-filling sensor, the proportion of gas, in particular the proportion of bubbles, in the liquid can be monitored, the monitoring preferably being repeated. If the gas content exceeds a certain value, then this indicates the end of the assumption and / or suction in the first container 31. The pumping power of the feed pump 20 can then be reduced to reduce the suction. In particular, in the case of a higher first container 31, the entire assumption with controlled and measured gas impact can thus be carried out.

As for example the embodiment of FIG. 3 can be removed between the feed pump 20 and the Füllgradmesseinrichtung 5, d. H. upstream of the level measuring device 5, a filter and / or sieve 18 are provided. Through this filter and / or this sieve 18 existing air bubbles can be crushed before the Füllgradmessung and evenly distributed, which increases the accuracy of the Füllgradmessung.

As in the example of FIG. 3, a pressure sensor 51 can be provided on the line 10. By means of this pressure sensor, the pressure of the fluid in the conduit 10 can be measured and taken into account in the flow rate determination. Suitably, the pressure sensor 51 is arranged in the immediate vicinity of the filling degree measuring device 5. He can, as in Fig. 3, but z. B. are also downstream of the consisting of the Füllgradmesseinrichtung 5 and the Strömungsmessein- device 6 measuring section are arranged. Preferably, the pressure sensor 51 is arranged on the same line side with respect to the feed pump 20 as the Füllgrademesseinrichtung. 5

The embodiment of FIG. 3 differs from the embodiments of FIG. 1 and 2 further characterized in that in the conduit 10 bottom side of the second container 32, a bottom valve 36 is provided. Such a bottom valve 36 can special be provided when the second container 32 is disposed on a tanker vehicle. In particular, a plurality of second containers 32 can also be provided, for example, on the same tanker vehicle, all of which are in each case connected via a bottom valve 36 to the line 10. In this case, according to the invention 32 air-penetrated milk can be introduced via the measuring section into different second container, which was only partially possible in a pick-tank tanker. The second container 32 may for example also be arranged on a trailer.

Another embodiment of a device according to the invention is shown in FIG. 4 shown. The in Fig. 4 can be used both for receiving and for discharging gas-laden liquids with simultaneous quantity detection. Instead of the check valve 16 of the devices of FIG. 1 to 3, the device of FIG. 4 a switchable valve 61 in the conduit 10. Such a switchable valve 61 can optionally also be provided as a bypass valve to the check valve 16.

In addition, the embodiment of FIG. 4 of the preceding embodiments, characterized in that in the conduit 10, a filter and / or sieve 18 'is provided between the second container 32 and the Füllgradmesseinrichtung 5. Furthermore, a pressure sensor 51 'between the measuring section and the feed pump 20 is arranged on the line 10. The filter and / or the sieve 18 'or the pressure sensor 51' may alternatively or additionally be provided to the sieve 18 or to the pressure sensor 51 of the embodiment of FIG. 3.

At the beginning of the dispensing operation with the device of FIG. 4, the bottom valve 36 is opened when the valve 14 is closed. If a plurality of second containers 32 are provided, then by opening the corresponding bottom valve 36, the desired container 32 to be emptied can be selected. If the line 10 was empty at the beginning of the dispensing process, the venting valve 42 can now be opened and the feed pump 20 can be flooded. The vent valve 42 is closed as soon as the detector 45 registers liquid. The liquid is then at least up to the valve 14. The filled Füllgradmesseinrich- device 5 can now be calibrated to the existing liquid. Subsequently, the feed pump 20 is put into operation and the valve 14 is opened. The volumetric flow of the flowing product is measured by means of the flow measuring device 6 and the gas bubble fraction is determined by means of the degree of volumetric measuring device 5 and is calculated to determine the flow rate with the volumetric flow.

The proportion of gas bubbles usually increases at the end of dispensing when a suction forms in the dispensing container. If the proportion of gas bubbles exceeds a certain value, which can be determined by means of the filling degree measuring device 5, the delivery rate of the delivery pump 20 can be reduced. This may result in a stop-and-go operation, both in acceptance and in delivery.

If the line 10 is filled with liquid prior to dispensing, the volume of liquid contained therein can be taken into account in determining the delivery quantity. For this purpose, the internal volume of the line 10 can be pre-leaked, for example.

Another embodiment of a device for quantity detection is shown in FIG. 5 is shown. The embodiment of FIG. 5 differs from the embodiments FIG. 1 to 3 essentially in that the Füllgrad- measuring device 5 'between the acceptance clutch 15 and the feed pump 20, ie suction side or. is provided upstream of the feed pump 20. This arrangement makes it possible to measure the gas content on the suction side of the feed pump 20 and to use the measurement results for controlling the feed pump 20. This is advantageous in that with the filling degree measuring device 5 'as a rule a particularly high measuring accuracy can be realized. With such an arrangement of the degree of filling measuring device 5 'is, as shown in FIG. 5, particularly advantageous, if in each case a pressure sensor 51, 51 'both intake and discharge side of the feed pump 20, d. H . on both sides of the feed pump 20, is provided. As a result, different bubble sizes at different pressure ratios on the intake and discharge side of the feed pump 20 are taken into account and can be detected by measuring to correct the calculated flow rate.

Another embodiment of a device according to the invention is shown in FIG. 6 shown. The embodiment of FIG. 6 differs from the previously described embodiments in that it is designed as a self-priming system with a vacuum generating device. The negative pressure generating device has an Ej ector 57, which is arranged at the end of the vent line 40. The vacuum generating device further comprises a compressed air generator 59, by means of which the ej ector 57 via a controllable valve 58 can be acted upon with compressed air. Alternatively or additionally, the vacuum generating device may also include a vacuum pump, which may also be arranged at the end of the vent line 40. By means of the vacuum generating device in the intake system (area A), a negative pressure can be generated when the vent valve 42 is opened. If now the acceptance valve 14 is opened, liquid is sucked in from the first container 1 from the first container 31. The air volume present in the tube 72 is blown out by the ej ector 57 and evacuated the intake system in the area B. As soon as the liquid from the first container 31 has reached the filling level measuring device 45, the system is filled and the venting valve 42 and in particular also the control valve 58 can be closed.

The - now filled - feed pump 20 can be put into operation, whereupon a pressure builds up and the second container 32 is filled. Any existing air bubble content is measured in the Füllgradmesseinrichtung 5 and with the flow rate, which is measured in the flow measuring device 6, charged.

If the proportion of air is too high, the pumping capacity of the feed pump 20 is reduced. In support of the negative pressure generating device can be activated with increasing proportion of gas in order to prevent that due to excessive Lufteinsσäläge, for example at the end of the assumption, the promotion of the feed pump 20 breaks off and / or the pressure built up is no longer sufficient to open the check valve 16 ,

The embodiment of FIG. 6 represents a self-priming pumping system with which accurate volume volume acquisitions are possible without an air separator or gas detector. In all embodiments of the method according to the invention, the gas bubble portion of the volume flow is measured and utilized to determine the total volume metrologically.

Claims

PATENT CLAIMS

1. A method for conveying and for the flow rate measurement of a liquid containing a gas portion, in particular milk or fuel, from a first delivery to a second delivery location, in which - pass the liquid with the gas content from the first delivery location (1) in a line (10) becomes,

- The liquid with the gas content through the line (10) is passed, - in the line (10) a degree of filling is performed, - in the line (10) a flow measurement is performed, - the liquid together with the gas content contained therein from the line (10) to the second place of delivery

(2) and - the results of the flow measurement are compared with those of the fill level measurement to determine the flow rate.

2. The method of claim 1, characterized g e k e n e c e n e,

- That for Füllgradmessung a conductivity measurement and / or a capacitance measurement is performed, and / or - That for flow measurement, a volume flow measurement, in particular a magnetic-inductive measurement is performed.

3. The method according to any one of claims 1 or 2, characterized in that e e n e c e s e s that the liquid is continuously passed through the conduit (10).

4. The method according to any one of claims 1 to 3, characterized in that a pressure measurement is carried out in the line (10), in particular in the region of a measuring point for the degree of filling.

5. Method according to one of claims 1 to 4, characterized in that the liquid is pumped through the line (10) by means of a delivery pump (20) arranged on the line (10).

6. The method of claim 5, characterized in that a pressure measurement in the conduit (10) both upstream and downstream of the feed pump (20) is performed.

7. The method according to any one of claims 5 or 6, characterized g e k e n e z e c h e n e,

- That the Füllgradmessung is carried out in particular upstream of the feed pump (20) and

- That the pumping power of the feed pump (20) is set Füllgradab- dependent.

8. The method according to any one of claims 1 to 7, characterized in that at least one of the preparation sites (1, 2) in a container (31, 32) is arranged, which is preferably carried out mobile.

9. Method according to one of claims 1 to 8, characterized in that for sucking the liquid into the line (10) at least temporarily a negative pressure in the line (10) is generated.

10. The method according to any one of claims 1 to 9, characterized in that the liquid for uniform distribution of the gas fraction upstream of the measuring point for the degree of filling by a cross-section of the line (10) arranged sieve (18) or by a cross-section of the line (10 ) arranged filter is passed.

11. The method according to any one of claims 1 to 10, characterized in that a gas column contained in the line (10) prior to the promotion of the liquid in the line (10) via a vent line (40) from the line (10) is derived.

12. A device for quantity detection in the acceptance and / or delivery of a liquid, preferably of milk or fuel, in particular for carrying out the method according to one of claims 1 to 11, with

at least one container (32) for receiving the liquid, - a conduit (10) communicating at its one end with the container (32) in fluid communication and having at its other end a flow opening (12) for the liquid,

- A on the line (10) arranged Fδrderpumpe (20) for pumping the liquid through the conduit (10),

- A degree of filling measuring device (5), which is arranged on the line (10),

- a flow-through device (6), which is arranged on the line (10), and

- An evaluation device for determining the delivered amount of liquid, which is in signal communication with the Füllgradmesseinrichtung (5) and the flow measuring device (6).

13. Device according to claim 12, characterized in that the line (10), at least outside the feed pump (20), the Füllgradmesseinrichtung (5) and / or the flow measuring device (6), an at least approximately constant line cross section.