Method for determining the interface height of the interface between the upper layer and the lower layer included in the concentrator

Abstract

The invention describes a method for determining an interface height (h) of an interface (1) between an upper layer (3) and a lower layer (5) comprised in a container (7) of a concentrator (9), wherein the concentrator (9) is designed to perform a concentrating process in which particles suspended in a medium supplied to the container (7) are separated from a liquid comprised in the medium, and wherein the upper layer (3) comprises liquid floating on a lower layer (5) comprising the particles, the method improving the usability of the interface height determination. The method comprises the following method steps: measuring the interface height (h) with an interface level measuring device (L) installed on the concentrator (9) during a time period in which the prevailing conditions of the concentrator (9) allow for the measurement, measuring a process variable (v) associated with the concentrating process performed by the concentrator (9) with a set of measuring devices installed on the concentrator (9) 1 ,…,v n ), and based on the measured process variable (v 1 ,…,v n ) using the calculation unit (35) to calculate at least once and provide a calculated interface height (h c ), wherein the calculation unit (35) is designed to calculate, based on a measured interface height (h) measured during at least one of the time periods and provided by the interface level measuring device (L) and the measuring device m ) and the measured process variable (v 1 ,…,v n ) to learn the calculated interface height (h c ) calculation.

Description

Technical Field

[0001] The present invention relates to a method for determining the interface height of an interface between an upper layer and a lower layer comprised in a concentrator container, wherein the concentrator is designed to perform a concentrating process in which particles suspended in a medium supplied to the container are separated from a liquid comprised in the medium, and wherein the upper layer comprises liquid floating on a lower layer comprising the particles, the method comprising the following method steps:

[0002] The interface height is measured with an interface level measuring device mounted on the concentrator during the time period when the conditions prevailing in the concentrator allow for the measurement to be carried out. Background Art

[0003] Thickeners are used in various industries to separate particles suspended in a medium, such as a slurry, from a liquid contained in the medium. For example, they are used in mineral refining processes.

[0004] Prior art concentrators designed to perform a concentrating process typically comprise a container and a supply pipe for supplying the medium to the container. Inside the container, gravity causes the solid particles included in the medium to gradually sink to the bottom of the container. As a result, the medium is separated into an upper layer comprising liquid and a lower layer comprising a correspondingly higher concentration of particles. This separation allows the liquid to be drawn out of the container through an overflow outlet located at a height at which the container wall is exposed to the upper layer internally. In addition, it allows the sediment comprising a high concentration of particles at the bottom of the container to be discharged through an overflow outlet located at or near the bottom of the container. In this case, the concentrator is typically equipped with a rotating rake comprising a scraper that pushes the sediment toward a conical discharge outlet located in the center of the bottom of the container.

[0005] It is known in the art that the settling and compaction rates of particles depend on the particle size and can be increased by adding chemical coagulants and / or flocculants to the medium.

[0006] The performance of the concentration process is usually monitored, regulated and / or controlled based on measurements of the interface height of the interface between the upper layer and the lower layer. Based on these measurements, the interface height is preferably regulated and / or controlled by regulating and / or controlling the supply of medium to the container, the extraction of liquid and / or the discharge of sediment. As an option, the efficiency of the process can be further improved by regulating and / or controlling the supply of coagulants and / or flocculants based on the measured interface height.

[0007] The interface height can be measured, for example, by an interface level measuring device capable of performing these measurements. For example, level measuring devices sold by the Endress+Hauser Group can be applied. One example is a time-of-flight measuring device, which measures the flight time required for a signal to travel to the interface and the flight time required for a signal reflected by the interface to return to the device. The measured flight time depends on the signal propagation speed and the travel distance, thus allowing the interface height to be determined based on the position of the measuring device relative to the container. Regardless of the type of interface level measuring device applied, interface height measurements can only be made during periods when the dominant measurement conditions of the concentrator allow these measurements to be made. As an example, time-of-flight measurements of the interface height require a minimum reflectivity of the interface and a sufficiently high signal amplitude of the received signal. In addition, reflections to and from the interface caused by reflectors positioned along the signal propagation path may reduce the amplitude of the signal component of the received signal caused by the reflection at the interface. Therefore, whether this signal component required to determine the interface height can be identified in the received signal depends on the dominant measurement conditions at the concentrator.

[0008] These problems can be solved to some extent by using special types of signals and signal processing methods such as methods for improving the signal-to-noise ratio, methods for tracking the interface height and advanced methods for identifying signal components of the received signal caused by reflections at the interface. Nevertheless, there is still a risk that the current measurement of the interface height may sometimes be impossible, in particular due to harsh and / or changing conditions prevailing at the concentrator and / or their influence on the interface conditions. Since the interface height constitutes a key parameter for monitoring, regulating and / or controlling the concentration process, the unavailability of the current interface height determination may reduce the quality and / or efficiency of the concentration process. Summary of the invention

[0009] It is therefore an object of the present invention to improve the usability of interface height determination.

[0010] The object is achieved by a method, in particular a computer-implemented method, for determining an interface height of an interface between an upper layer and a lower layer comprised in a concentrator container, wherein the concentrator is designed to perform a concentrating process in which particles suspended in a medium supplied to the container are separated from a liquid comprised in the medium, and wherein the upper layer comprises liquid floating on a lower layer comprising the particles, the method comprising the following method steps:

[0011] measuring the interface height with an interface level measuring device mounted on the concentrator during a time period when the conditions prevailing at the concentrator allow for the measurement,

[0012] measuring process variables related to the concentrating process performed by the concentrator using a set of measuring devices installed on the concentrator, and

[0013] calculating the interface height at least once based on the measured process variables provided to the calculation unit and providing the calculated interface height to the calculation unit,

[0014] Therein the calculation unit is designed to learn the calculation of the calculated interface height based on a measured interface height and a measured process variable measured during at least one of the time periods and provided by the interface level measurement device and the measuring device.

[0015] An advantage of the method is that once the calculation has been learned, the calculated interface height(s) can be determined at any time, regardless of whether the interface height can be measured by the interface level measuring device. Thus, based on the invention, the interface height can be determined during time periods when the prevailing conditions in the concentrator do not allow the interface height to be measured.

[0016] A first improvement of the method comprises a method according to the invention, wherein:

[0017] the learning of the calculation of the at least one calculated interface height is performed by the calculation unit, which performs a learning process based on training data, the training data being determined as or based on measured interface heights and measured process variables measured and provided by the interface level measurement device and the group of measurement devices during at least one of the time periods, and

[0018] Only measured interface heights and measured process variables which are measured during one or more time intervals in which the measured interface height is reliable are used as training data or for determining the training data.

[0019] According to a second improvement, the reliability or unreliability of the measured interface height is determined by at least one of the following operations:

[0020] a) monitoring the measured interface height,

[0021] b) determining a rate of change of the interface height as a function of time based on said measured interface height and determining, based on said rate of change, as unreliable the measured interface heights determined during time intervals in which the rate of change exceeds a predetermined threshold value or exceeds a threshold value given by a maximum velocity of the interface height expected during the performance of the concentration process,

[0022] c) determining as unreliable a measured interface height that exceeds a predetermined height range or exceeds a height range given by a range of interface heights to be expected during normal performance of the enrichment process,

[0023] d) monitoring a signal-to-noise ratio of a measurement signal obtained by the interface level measurement device and identifying a measured interface height determined based on a measurement signal having a signal-to-noise ratio less than a predetermined threshold as unreliable,

[0024] e) applying a filter to the measured interface height, determining noise superimposed on the filtered interface height based on the measured interface height and the filtered interface height, and identifying the measured interface height as unreliable when the noise exceeds a predetermined threshold,

[0025] f) performing a reference measurement of the interface height and identifying a measured interface height that deviates from a corresponding reference measurement by more than a predetermined threshold as unreliable,

[0026] g) determining at least one of at least one physical model for estimating the interface height based on at least one of the measured process variables and at least one statistical model for estimating the interface height based on at least one of the measured process variables, and based on the estimated interface height determined based on at least one of the models, performing at least one of the following:

[0027] g1) identifying as unreliable a measured interface height that deviates from a corresponding estimated interface height by more than a predetermined threshold or by more than a threshold determined based on the uncertainty inherent in the estimate,

[0028] g2) identifying unreliable measured interface heights included in training data determined for learning the calculation of said calculated interface height, and eliminating said identified unreliable measured interface heights from said training data, and

[0029] g3) providing notification of an unreliable measured interface height identified based on said estimated interface height, and

[0030] h) performing at least one other method capable of determining the reliability or unreliability of the measured interface height.

[0031] According to a third improvement, the method according to the invention further comprises at least one of the following method steps:

[0032] a) determining training data for learning the calculation of said calculated interface height by additionally performing outlier detection or outlier detection implemented as part of a machine learning process, identifying outliers included in said training data based on said outlier detection, and eliminating said identified outliers from the training data for learning said calculation, and

[0033] b) numerically determining a value of at least one of the process variables based on at least one of the measured process variables or based on the measured interface height and at least one or all of the measured process variables, wherein: the numerically determined value comprises at least one of the following: at least one numerically determined value determined by interpolation, at least one numerically determined value determined by simulation, and at least one numerically determined value determined by Monte Carlo simulation, and performing at least one of the following:

[0034] applying a numerically determined value determined for a time included in at least one of the following time periods or time intervals during which the measured interface height and the measured process variable for determining training data for learning the calculated interface height were measured as additional training data, and

[0035] In addition to the measured process variables, numerical determination values ​​determined for a time occurring after learning of the calculation of the calculated interface height has been completed are applied to calculate the calculated interface height.

[0036] According to a fourth improvement, the method according to the invention comprises the following method steps:

[0037] Determine at least one secondary variable or at least one secondary variable directly or indirectly related to the interface height based on at least one of the measured interface height and at least one of the measured process variables, and perform at least one of the following operations:

[0038] a) using a secondary variable determined for a time period or time interval during which a measured interface height and said measured process variable for determining calculated training data for learning said calculated interface height were measured as additional training data, and

[0039] b) applying, in addition to said measured process variables, secondary variables determined for a time occurring after learning of the calculation of said calculated interface height has been completed, to calculate said calculated interface height.

[0040] According to a fifth improvement, the method according to the invention comprises the following method steps: for at least one of the process variables, at least one of the following method steps is performed:

[0041] calculating and providing a calculated value of the process variable at least once, and

[0042] detecting and indicating a problem with a measurement device measuring a process variable when a deviation between a measured process variable measured by the measurement device and a corresponding calculated value exceeds a predetermined threshold or exceeds a threshold determined based on an uncertainty inherent in the calculation,

[0043] The calculated value of the process variable includes at least one of the following:

[0044] a) at least one calculated value determined based on a physical model or a statistical model for estimating a corresponding process variable based on some or all of the other process variables measured by the measuring device or based on the measured interface height and some or all of the other process variables measured by the measuring device, and

[0045] b) at least one calculated value calculated by the calculation unit, wherein:

[0046] b1) the calculation unit is designed to learn the calculation of the calculated value of the process variable based on the measured process variable or based on the measured process variable and the measured interface height, and

[0047] b2) calculating each of the calculated values ​​of the corresponding process variables based on some or all of the other process variables measured and provided by the measuring device, or based on the measured interface height and based on some or all of the other process variables measured and provided by the measuring device.

[0048] The present invention also includes a sixth improvement, wherein at least one of the measured interface height, at least one of the measured process variables, and some or all of the training data is provided to the computing unit by at least one of the following:

[0049] a) at least one of the interface level measuring device and the measuring devices included in the group;

[0050] b) a superordinate unit connected to and / or communicating with at least one or all of: the interface level measuring device and at least one of the measuring devices included in the group, and

[0051] c) An edge device connected to and / or in communication with at least one or all of: the interface level measurement device and at least one of the measurement devices included in the group.

[0052] According to a seventh improvement, the process variable and the interface height are correlated.

[0053] An eighth improvement comprises the method according to the invention, wherein the set of measuring devices measuring and providing said process variable comprises at least one of the following:

[0054] a flow meter installed in or on a supply pipe, the supply pipe supplies the medium to the container, the flow meter measuring the flow rate of the medium supplied to the container,

[0055] a flow meter mounted in or on the overflow outlet pipe, which measures the flow rate of liquid drawn from the container through the overflow outlet pipe, and

[0056] a flow meter installed in or on a downflow outlet pipe connected to an downflow outlet located at or near the bottom of the container, the flow meter measuring the flow rate of sediment discharged from the container through the downflow outlet pipe,

[0057] a flow meter installed in or on a supply line, the supply line supplying a product to the container, the product being a product including at least one of a coagulant and a flocculant, the flow meter measuring a flow rate of the product supplied to the container through the supply line,

[0058] Density measuring equipment, which measures the density of sediment at or near the bottom of a container,

[0059] a density measuring device which is installed in or on the downflow outlet pipe and measures the density of the sediment discharged from the container through the downflow outlet pipe,

[0060] a pressure measuring device which measures the static pressure of the fluid prevailing at a predetermined height inside the container or at or near the bottom of the container,

[0061] a torque measuring device that measures the torque applied by a motor to rotate a rake mounted on the concentrator about a longitudinal rotation axis, wherein the rake is a rake for pushing the sediment toward an underflow outlet located at the bottom of the container,

[0062] a height measuring device which measures the insertion height of the rake relative to a predetermined reference height,

[0063] a turbidity measuring device mounted in or on the overflow outlet pipe for measuring the turbidity of liquid drawn from the container through the overflow outlet pipe, and

[0064] At least one other measuring device that measures at least one other process variable.

[0065] According to a ninth improvement, the method further comprises the following method steps: during at least one time interval in which the measured interface height measured by the interface level measuring device is unavailable or unreliable:

[0066] calculating a calculated interface height based on the measured process variable, and

[0067] At least one of providing the calculated interface height and performing at least one of monitoring, regulating and controlling a concentrating process performed on the concentrator based on the calculated interface height is performed.

[0068] According to a tenth improvement, the method according to the invention comprises the following method steps: during at least one or all of the time periods during which the measurement of the interface height is allowed and performed by the interface level measuring device:

[0069] determining the calculated interface height, and

[0070] performing at least one of providing the calculated interface height, and performing at least one of monitoring, regulating, and controlling a concentrating process performed on the concentrator based on at least one of the measured interface height, the calculated interface height, and an average of the measured and calculated interface heights.

[0071] According to an eleventh improvement, the method according to the invention comprises the following method steps: during at least one or all of the time periods during which the interface level measuring device allows and performs the measurement of the interface height, determining the calculated interface height and performing at least one of the following:

[0072] monitoring the interface level measuring device and the computing unit based on the measured and the calculated interface height,

[0073] A fault is detected when a deviation between one of the measured interface heights and the corresponding calculated interface height exceeds a predetermined threshold, and

[0074] When a fault is detected, a notification is provided to inform of the fault.

[0075] According to a twelfth improvement, the method according to the invention comprises at least once the following method steps:

[0076] providing one of said calculated interface heights as a reference height for interface height measurement,

[0077] determining, based on the reference height, for the interface level measurement device a restricted measurement range including the reference height, and

[0078] In this limited measurement range, the interface height is measured using the interface level measuring device.

[0079] The limited measurement range is determined as a portion of the full measurement range of the interface level measurement device, or is determined as a range including interface heights that deviate from the reference height by less than a predetermined percentage, less than 10% or less than 5% of the width of the full measurement range.

[0080] A further improvement is given by improving upon the twelfth improvement,

[0081] The interface level measuring device:

[0082] is a time of flight measurement device that determines the measured interface height based on the flight time required for a signal to travel to the interface and for its reflection to return, and

[0083] comprising a signal processing and evaluation unit which determines an echo function representing the signal amplitude of the echo signal as a function of the flight time, identifies a maximum of the echo function caused by reflections at the interface, and determines the measured interface height based on the flight time at which this maximum occurs, and

[0084] The measurement of the interface height within the limited measurement range is performed by at least one of the following:

[0085] excluding all amplitude peaks comprised in the echo function which occur outside said restricted measurement range,

[0086] determining a maximum value corresponding to the reflection at the interface as a maximum value of an amplitude peak value or an amplitude peak value having a highest peak amplitude included in the echo function within the restricted measurement range, and

[0087] A method of identifying a maximum of an echo function caused by reflections at an interface within the restricted measuring range is performed.

[0088] The present invention also includes a computer program for determining an interface height of an interface between an upper layer and a lower layer included in a concentrator container according to the method according to the present invention, in particular for determining at least one calculated interface height according to the method according to the present invention, the computer program comprising instructions which, when the program is executed by a computer, cause the computer to perform the method according to the present invention.

[0089] The present invention also includes an improvement in a computer program, wherein the instructions include the following instructions, which, when the program is executed by a computer, cause the computer to perform learning of the calculation based on the measured interface height and the measured process variable, and to perform calculation of at least one calculated interface height based on the learned calculation and the measured process variable.

[0090] The invention also comprises a computer program product comprising a computer program according to the invention and at least one computer readable medium, wherein at least the computer program is stored on the computer readable medium. BRIEF DESCRIPTION OF THE DRAWINGS

[0091] The invention and further advantages are explained in more detail using the attached drawings.

[0092] Figure 1 shows: a system for determining the height of an interface,

[0093] Figure 2 shows: an echo function determined by a time-of-flight interface level measurement device during ideal measuring conditions; and

[0094] Figure 3 Shown is an echo function determined by a time-of-flight interface level measuring device during difficult measuring conditions. DETAILED DESCRIPTION

[0095] The present invention provides a method for determining an interface height h of an interface 1 between an upper layer 3 and a lower layer 5 comprised in a container 7 of a concentrator 9 . Figure 1 An example of a system for performing the method is shown. The concentrator 9 is designed to perform a concentrating process in which particles suspended in a medium supplied to the concentrator 9 are separated from a liquid included in the medium. In the example shown, the concentrator 9 comprises a supply pipe 11 for supplying the medium to the container 7. The supply of the medium can be regulated and / or controlled, for example, by a valve V1 inserted in the supply pipe 11. Inside the container 7, gravity causes the solid particles included in the medium to gradually sink to the bottom of the container 7. As a result, the medium separates into an upper layer 3 including liquid floating on a lower layer 5 including particles. Typically, the concentration of particles included in the lower layer increases toward the bottom of the container 7, and causes the lower layer to include a precipitate having the highest particle concentration at or near the bottom.

[0096] The concentrator 9 comprises an overflow outlet 13 and an overflow outlet 15. The overflow outlet 13 is located at the height of the container wall of the container 7, the overflow outlet 13 being internally exposed to the upper layer 3 during the performance of the concentration process, thus allowing liquid to be extracted from the container 7. The extraction of liquid can be regulated and / or controlled, for example, by a valve V2 inserted in an overflow outlet pipe 17, which is connected to the overflow outlet 13. The overflow outlet 15 is located at the bottom of the container 7 or near the bottom, thereby allowing sediment deposited at the bottom of the container 7 to be discharged. The discharge of the sediment can be regulated and / or controlled, for example, by a valve V3 inserted in an overflow outlet pipe 19, which is connected to the overflow outlet 15. As an option, the discharge rate at which the sediment can be discharged can be increased by a pump 21 inserted in the overflow outlet pipe 19.

[0097] As an optional feature, the thickener 9 is preferably equipped with a rotating rake 23, for example a rake 23 comprising scrapers, which pushes the sediment towards the overflow outlet 15. In this case, the overflow outlet 15 is preferably conical and located in the center of the container 7 bottom.

[0098] As another optional feature, the concentrator 9 may comprise supply means for supplying a product to the container 7, the product being a product comprising a coagulant and / or a flocculant. Figure 1 As shown, the supply device may for example comprise a reservoir 25 containing the product and a supply line 27 extending from the reservoir 25 to the container 7. The product supply provided by the supply device may for example be regulated and / or controlled by a valve V4 inserted in the supply line 27.

[0099] The concentrator 9 is equipped with an interface level measuring device L, which is designed to measure the interface height h of the interface 1 between the upper layer 3 and the lower layer 5. In this case, interface level measuring devices known in the art can be applied. As an example, the interface level measuring device L can be, for example, a time-of-flight measuring device, which determines the interface height h based on the flight time required for the signal to travel to the interface 1 and its reflection back.

[0100] Figure 1 An example of an ultrasonic time-of-flight measuring device is shown, which comprises a transducer 29 which transmits an ultrasonic signal, such as a pulse, to an interface 1 and receives an echo signal, which comprises reflections of the transmitted signal reflected back to the transducer 29. Like time-of-flight measuring devices known in the art, the interface level measuring device L preferably comprises a signal processing and evaluation unit which determines an echo function A(tof) representing the signal amplitude A of the echo signal as a function of the flight time tof, identifies a maximum value E of the echo function A(tof) caused by reflections at the interface 1 L , and based on the occurrence of the maximum value E L The flight time t EL Determine the interface height h.

[0101] Figure 2 A very simplified example of an echo function A(tof) is shown, which includes the time of flight t EL The clear maximum value E L The flight time t EL corresponds to the distance between the transducer 29 and the interface 1 and can therefore be converted into a measured interface height h based on the signal propagation speed and the position of the transducer 29 relative to the container 7 m Obviously, other types of time-of-flight level measuring devices or interface level measuring devices operating on other measuring principles may be applied instead, for example devices comprising a capacitive probe measuring the capacitance of a capacitor formed by the probe and the container wall, or radiation level measuring devices.

[0102] Furthermore, a set of measuring devices is installed on the concentrator 9. Each of these measuring devices measures one or more process variables v1, ..., v related to the concentrating process performed on the concentrator 9. n Thus, the combination of measuring devices measures and provides the measured process variables v1,…,v n The set of individual process variables v1,…,v measured by each of these devices n In addition to the interface level measuring device L, the set of measuring devices preferably comprises at least two or all measuring devices installed on the concentrator 9, for example for monitoring, regulating and / or controlling the concentrating process. This has the advantage that the corresponding measured process variables v1, ..., v n .

[0103] like Figure 1 As shown in the example shown, the set of measuring devices may, for example, include at least one of the following:

[0104] a flow meter F1 , which is installed in or on the supply pipe 11 and measures the flow rate of the medium supplied to the container 7 ,

[0105] a flow meter F2 mounted in or on the overflow outlet pipe 17 and measuring the flow rate of the liquid drawn from the container 7 through the overflow outlet pipe 17, and

[0106] a flow meter F3, which is installed in or on the downflow outlet pipe 19 and measures the flow rate of sediment discharged from the container 7 through the downflow outlet pipe 19,

[0107] Regardless, these devices are usually required to perform the concentration process.

[0108] Additionally or alternatively, the set of measuring devices may for example include at least one of the following:

[0109] a flow meter F4 installed in or on the supply line 27 and measuring the flow of the product supplied to the container 7 via the supply line 27,

[0110] - a density measuring device D1 which measures the density of the sediment at or near the bottom of the container 7,

[0111] a density measuring device D2, which is installed in or on the downflow outlet pipe 19 and measures the density of the sediment discharged from the container 7 through the downflow outlet pipe 19,

[0112] a pressure measuring device P for measuring the static pressure of the fluid prevailing at a predetermined height inside the container 7 or at or near the bottom of the container 7,

[0113] a torque measuring device T which measures the torque applied by the motor 31 to rotate the rake 23 about the longitudinal axis of rotation, and

[0114] a height measuring device H which measures the insertion height of the rake 23 relative to a predetermined reference height,

[0115] a turbidity measuring device O, which is installed in or on the overflow outlet pipe 17 and measures the turbidity of the liquid drawn from the container 7 through the overflow outlet pipe 17, and

[0116] - at least one other measuring device which measures at least one other process variable.

[0117] As an option, the interface level measurement device L and / or at least one or all of the measurement devices in the group may be connected to and / or communicate with the superordinate unit 33. In this case, hardwired or wireless connections and / or communication protocols known in the art may be used, such as LAN, W-LAN, Fieldbus, Profibus, Hart, Bluetooth, near field communication, etc. As an example, the superordinate unit 33 may, for example, include a control system that performs at least one of the following: management process control, process visualization and process monitoring of the concentration process performed by the concentrator 9.

[0118] During the execution of the method for determining the interface height h, the set of measuring devices measures and provides measured process variables v1, ..., v n Furthermore, the interface level measuring device L measures and supplies the measured interface height h during the time periods in which the conditions prevailing in the concentrator 9 allow these measurements to be made. m These time periods are obviously limited by the measured interface height h m The time intervals during which this can be used are those which can be and have been measured and provided by the interface level measuring device L.

[0119] Depending on the application and / or type of the respective measuring device, the interface height h and / or the process variables v1,…,v n The measurement of can be performed, for example, continuously, periodically or intermittently by a corresponding device. Thus, the interface height h and the process variables v1,…,v n At least two or all of the measurements may be performed simultaneously or at different measurement times t.

[0120] In addition, the measured interface height h m , measured process variables v1,..,v n and the corresponding measurement time t are provided to the calculation unit 35. The calculation unit 35 is designed to learn the calculated interface height h c , where each calculated interface height h cis based on the measured process variables v1, .., v supplied to the calculation unit 35 n Calculated. Based on the measured interface height h measured and provided to the calculation unit 35 m and the measured process variables v1,..,v n To perform learning, measure the interface height h m and the measured process variables v1,..,v n The learning process is preferably performed by the calculation unit 35 based on the training data, based on the measured interface height h obtained based on the corresponding measurements performed during at least one of these time periods. m and the measured process variables v1,..,v n Identify the training data.

[0121] Preferably, only the interface height h is measured in m The measured interface height h measured during one or more time intervals is not only available but also reliable m and the measured process variables v1,..,v n These time intervals are preferably determined by performing a method capable of determining the measured interface height h m The reliability or unreliability of at least one method is identified.

[0122] Measured interface height h m The reliability or unreliability of the measured interface height h can be determined, for example, by monitoring the measured interface height h m As an example, the rate of change of the interface height h is preferably based on the measured interface height h m Based on the rate of change, the measured interface height h measured during the time interval in which the rate of change exceeds a predetermined threshold, for example a threshold given by the maximum speed of the interface height h expected during normal performance of the concentration process m Additionally or alternatively, the measured interface height h exceeds a predetermined height range, such as a range given by an expected interface height h range during normal performance of the enrichment process. m Preferably, it is also determined to be unreliable.

[0123] As an additional or alternative option, the signal-to-noise ratio of the measurement signal obtained by the interface level measuring device L can be monitored. In this case, the measured interface height h is determined based on the measurement signal having a signal-to-noise ratio less than a predetermined threshold value. m Identified as unreliable.

[0124] As an additional or alternative option, a filter is applied to the measured interface height h m, and based on the measured interface height h m and the filtered interface height to determine the interface height h superimposed on the filter m In this case, the measured interface height h is measured when the noise exceeds a predetermined threshold. m Identified as unreliable.

[0125] As an additional or alternative option, a reference measurement of the interface height may be performed. In this case, the interface height h of a measurement that deviates from the corresponding reference measurement by more than a predetermined threshold is m These reference measurements can be performed, for example, by an additional interface level measurement device installed on the concentrator. As an option, this additional interface level measurement device can be removed once sufficient training data has been determined.

[0126] Additionally or alternatively, a method for determining the measured interface height h can be used. m at least one other method of reliability or unreliability.

[0127] Measured interface height h m and / or measured process variables v1,..,v n At least one of the following can be provided directly to the calculation unit 35 by the interface level measurement device L and / or the corresponding measurement device. As an alternative currently preferred option, at least one of the following is provided to the calculation unit 35 by the superior unit 33 and / or by the edge device 37: the measured interface height h m , measured process variables v1,..,v n At least one of the measured interface height h m and the measured process variables v1,..,v n At least some or all of the training data determined by at least one or all of at least one of the above, as indicated by arrows A1 and A2 and / or B1 and B2, respectively, the superordinate unit 33 and / or the edge device 37 is connected to and / or communicates with at least one or all of the following: an interface level measuring device L and a measured process variable v1, .., v n At least one or all of the measuring devices in the group of measuring devices.

[0128] As an example, the training data may be provided to the computing unit 35, for example in the form of a time series, for example in the form of a time series of measurement results of individual devices, and / or in the form of one or more time series, each time series comprising measurement results derived simultaneously by at least two of the devices.

[0129] The computing unit 35 can, for example, be embodied as a unit comprising hardware, such as a computer or a computing system located near the concentrator 9 or at a remote location. As an alternative, cloud computing can be applied. Cloud computing names a scheme in which IT infrastructure, such as hardware, computing power, memory, network capacity and / or software, is provided via a network, such as via the Internet. In this case, the computing unit 35 is embodied in the cloud and is connected via the Internet, such as via a communication network, such as TCP / IP, to at least one or all of the following: the interface level measuring device L and at least one of the measuring devices included in the group. The interface height h calculated is learned. c The method steps for calculating the process variables v1, .., v n and the interface height h are correlated, thus exhibiting a deterministic behavior representative of the state of the concentrator 9, allowing the execution of the learning process.

[0130] As an example, the flow rate of the medium supplied to the container 7 causes the interface height h to vary corresponding to the separation rate achieved by the thickener 9, the flow rate of the liquid extracted from the container 7 and the flow rate of the sediment discharged from the container 7. In addition, the hydrostatic pressure at the bottom of the container 7 corresponds to the total level given by the sum of the thickness of the upper layer 3 and the thickness of the lower layer 5 extending above the pressure measuring device P and their average density in the direction parallel to the gravity direction. Therefore, the hydrostatic pressure is indirectly related to the separation rate achieved by the thickener 9, the flow rate of the liquid extracted from the container 7 and the flow rate of the sediment discharged from the container 7, and therefore also to the interface height h. In addition, the insertion height of the rake 23 and / or the change in the torque required to rotate the rake 23 at a certain speed depends on the thickness and density of the lower layer 5 and / or the sediment, which indicates the separation rate achieved by the thickener and is therefore also related to the interface height h, and the turbidity of the liquid indicates the degree of separation achieved by the thickening process, which is at least indirectly related to the interface height h.

[0131] The computing unit 35 is preferably equipped with artificial intelligence that performs a learning process. The learning process may be, for example, a supervised learning process, in which the behavior of the interface height h is learned based on training data, the training data comprising the interface height h measured by m The output value given by the measured process variables v1,..,v nThe corresponding input values ​​given. In this case, the learning process preferably provides a learning model that represents the interdependence between the input values ​​and the output values. An example of a supervised learning process is a so-called recursive neural network (RNN) with long short-term memory (LSTM), which is particularly suitable for time series. However, the present invention is neither limited to supervised learning nor to neural networks. In addition to supervised learning and / or neural networks, or in combination with supervised learning and / or neural networks, other techniques and / or methods of machine learning can be used, such as methods for determining deterministic models, methods applying robust covariance and / or methods applying Monte Carlo simulation.

[0132] As an option, the determination of the training data may further include the method step of performing an outlier detection. The outlier detection may be implemented, for example, as part of a machine learning process. Based on the outlier detection, outliers included in the training data are identified and subsequently eliminated from the training data for the learning calculation.

[0133] Regardless of the type of learning process applied, for process variables v1,..,v based on measurements n Calculate the interface height h of the calculation c The model of is preferably determined based on training data and stored in the computing unit 35 .

[0134] As an example, the calculation unit 35 may for example include determining the calculated interface height h c In principle, a soft sensor is a virtual sensor for determining the interface height h, which does not measure the interface height h directly, but is based on inputs (in the present case measured process variables v1, .., v n ) to calculate the interface height h c In combination with artificial intelligence, this has the advantage that the interface height h is closely related to the dynamic behavior of the concentration process, in particular the measured process variables v1,..,v included in the training data. n and / or the interface height h used to calculate the calculation c The measured process variables v1,..,v n The interrelationships between the dynamic behaviors, especially the dynamic interrelationships, can be taken into account.

[0135] Based on a learning calculation, in particular a learning model, learned by the computing unit 35, the computing unit 35 calculates, after having carried out the learning process, the measured process variables v1, .., v1 supplied to the computing unit 35. n Calculate and provide at least one calculated value h of the interface height h c .

[0136] The method according to the invention is preferably performed as a computer-implemented method. In this case, the above method steps, in particular the method steps performed by the calculation unit 35, are performed by a computer program for determining interface heights, in particular for determining at least one calculated interface height h according to the above method. c Therefore, the present invention is also implemented in the form of a computer program including instructions, which, when executed by a computer, causes the computer to perform the method according to the present invention as described above. In particular, these instructions include, when the program is executed by a computer, causing the computer to calculate the interface height h based on the measured interface height h. m and the measured process variables v1,..,v n Perform computational learning and based on the learned computations and measured process variables v1,..,v n To perform at least one calculation of the interface height h c In addition, the present invention also includes a computer program product, which includes the above-mentioned computer program and at least one computer-readable medium, wherein at least the computer program is stored on the computer-readable medium.

[0137] The method, the computer program and the computer program product all comprise the advantages described above.

[0138] As mentioned above, the above method, in particular the learning process, is performed based on training data, which are based on the interface height h measured and provided by the interface level measuring device L. m The measured interface height h measured during one or more time periods m and the measured process variables v1,..,v n This training data is preferably limited to only include the interface height h measured based on m The measured interface height h measured during one or more time intervals is not only available but also reliable m and the measured process variables v1,..,v n Determined data.

[0139] The training data preferably comprises measured interface heights h measured during respective time periods or time intervals and corresponding measurement times t. m and the corresponding measured process variables v1,..,v n .

[0140] As an option, the process variables v1,..,v measured by the measuring device n of at least one numerically determined value v 1k ,..,v nkcan be determined, for example, by the computing unit 35 and / or by the superordinate unit 33 and / or the edge device 37 and provided to the computing unit 35. These numerically determined values ​​v 1k ,..,v nk Preferably including based on the measured process variables v1,..,v n At least one of the above is performed or based on the measured interface height h m and the measured process variables v1,..,v n The corresponding process variables v1, .., v are numerically determined by interpolation or by simulation, for example by Monte Carlo simulation, of at least one or all of the processes. n The interpolated and / or simulated value v 1k ,..,v nk Preferably for the interface height h measured for determining the training data m and the time included in the time period or time interval of the measured process variable to determine the value v of these numerical determinations 1k ,..,v nk In this case, they are used as additional training data to learn the measured process variables v1,..,v n The calculated interface height h c As an option, they can also be determined for a time occurring after the learning process has been completed and furthermore used for the measured process variables v1, .., v n To calculate the interface height h c .

[0141] As another option, at least one secondary variable v s According to the measured interface height h m and the measured process variables v1,..,v n The secondary variable v is determined by at least one or all of s Preferably includes at least one secondary variable v directly or indirectly related to the interface height h s For example, the secondary variable v s It may include a function of the ratio given by the flow rate of the product supplied to the container 7 divided by the flow rate of the medium supplied to the container 7 and / or a mass balance or a function of the mass balance determined based on the difference between the mass flow rate of the medium entering the container 7 and the sum of the mass flows of the liquid and the sediment leaving the container 7. In this case, for the interface height h included in the measurement used to determine the training data m and the measured process variables v1,..,v n The secondary variable v is determined by the time in the time period or time interval sis preferably used as process variable v1, .., v which is also used for measurement n Additional training data to learn the calculated interface height h c As an option, they can also be determined for a time occurring after the learning process has been completed and, moreover, used for the measured process variables v1, .., v n To calculate the interface height h c In both cases, they can also be processed, for example, as additional process variables that are combined with the measured process variables v1, .., v n The same approach is applied.

[0142] As another option, at least one physical model and / or statistical model may be determined, which is used to determine the physical model and / or statistical model based on the measured process variables v1, .., v n The models are preferably determined based on data included in a restricted part of the training data. The physical models preferably include at least one model determined based on a known physical dependence of the interface height h on the corresponding process variable(s), for example the dependence of the interface height h on the mass balance of the supplied medium, the pumped liquid and the discharged sediment. Additionally or alternatively, they preferably include a model determined by determining the measured interface height h m and the measured process variables v1,..,v n The statistical model is preferably determined based on a statistical analysis of the data. The estimated interface height determined based on at least one of these models is preferably used to monitor the measured interface height h m Additionally or alternatively, a measured interface height h deviates from a corresponding estimated interface height determined based on a corresponding model by more than a predetermined threshold, for example a threshold determined based on an inherent uncertainty of the estimate m , is preferably identified as unreliable. Based on this, the unreliable measured interface heights h included in the training data m is preferably identified and subsequently eliminated from the training data used to learn the calculation. As another option, unreliably measured interface heights h m , especially the unreliable measured interface height h measured after performing the learning process m , preferably based on the corresponding estimated interface heights, and preferably providing an interface height h informing the identified unreliable measurement(s) m The corresponding notification.

[0143] The calculated interface height h calculated and provided by the above method c can be applied in various ways. As an option, the calculated interface height hc The interface height h is preferably measured in m These calculated interface heights h are calculated and provided during at least one time interval when the interface height h is unavailable or unreliable. c is preferably used to monitor, regulate and / or control the concentration process performed on the concentrator 9. In this case, the calculated interface height h c is preferably provided to the superordinate unit 33, which calculates the interface height h based on these c Performs monitoring, regulation and / or control of the concentration process.

[0144] Additionally or alternatively, the calculated interface height h c Preferably, it is also calculated and provided during at least one or all of the time periods that allow the interface height h to be measured. During these time periods, the measured interface height h m Assume that it is measured by the interface level measuring device L. This allows to calculate the interface height h based on the measurements during these time periods. m and / or calculated interface height h c To perform monitoring, regulation and / or control of the concentration process. In this case, the measured interface height h m and / or calculated interface height h c is preferably provided to a superordinate unit 33 which determines the measured interface height h m and / or calculated interface height h c Monitoring, regulation and / or control of the concentration process is performed. As an example, the monitoring, regulation and / or control can be based on the measured interface height h m and the calculated interface height h c is performed using the average value of

[0145] The regulation and / or control of the concentration process preferably includes the following steps based on the measured interface height h m and / or calculated interface height h c Adjusting and / or controlling the interface height h. This method step can be performed, for example, manually or in a semi-automatic or fully-automatic manner, for example by means of a superordinate unit 33, by adjusting and / or controlling the flow rate of the medium supplied to the container 7, the flow rate of the liquid drawn out of the container 7 through the overflow outlet 13, the flow rate of the sediment discharged from the container 7 through the underflow outlet 15, and / or by means of a flow rate based on the measured interface height h m and / or calculated interface height h c Each of these flows and each of the supplies can be adjusted accordingly, for example, by means of valves V1 , V2 , V3 , V4 foreseen in the supply pipe 11 , the overflow outlet pipe 17 , the underflow outlet pipe 19 and the supply line 27 .

[0146] As an additional option, the measured interface height h is obtained simultaneously m and the calculated interface height h c Preferably, it is used to monitor the interface level measuring device L and the computing unit 35. The method steps are preferably executed by the superordinate unit 33 and / or the computing unit 35. In addition, when the measured interface height h m The corresponding calculated interface height h c When the deviation between exceeds a predetermined threshold, a fault is preferably detected. When a fault is detected, a notification informing of the fault is preferably provided.

[0147] As another option, the calculated interface height h c At least one of the interface level measuring devices L is preferably used as a reference height h for the interface height measurement performed by the interface level measuring device L. ref In this case, based on the corresponding reference height h ref Determine the corresponding reference height h ref The interface level measuring device L has a limited measuring range LR, and the interface level measuring device L performs the measurement of the interface height h within the limited measuring range LR. In this case, the calculated interface height h c Or the corresponding limited measuring range LR can be provided to the interface level measuring device L, for example, via the superordinated unit 33, the edge device 37 or directly. The interface level measuring device L will then determine and apply the limited measuring range LR or apply the limited measuring range LR provided to it during the next measurement of the interface height h. Despite the minimum height h of the interface level measuring device L from the interface 1 min To the maximum height h max The full measurement range FR needs to be large enough to cover all interface heights h that may occur during the normal execution of the concentration process, but the restricted measurement range LR is preferably determined to be significantly narrower. Therefore, the restricted measurement range LR only includes a small part of the full measurement range FR. As an example, the restricted measurement range LR can be determined, for example, to include deviations from the reference height h ref A percentage X smaller than a predetermined percentage X, for example smaller than 10% of the width of the full measuring range FR, preferably smaller than 5% (for example, by LR:=h ref + / -X%(h max -h min ))’s range of all interface heights h.

[0148] Limit the measuring range to the reference height h refThe determined limited measurement range LR helps to improve the measurement capability, measurement accuracy and measurement reliability of the interface level measurement device L. For example, under unfavorable measurement conditions, the echo function A(tof) determined by the time-of-flight level measurement device as described above may include a large number of overlapping, partially overlapping and / or non-overlapping amplitude peaks E i For illustrative purposes, Figure 3 A very simplified example of such an echo function A(tof) is shown, which includes a relatively small number of amplitude peaks E1, ..., E5. The amplitude peaks E1, ..., E5 included in the echo function A(tof) are caused by reflections on various reflectors distributed along the signal transmission path. Due to the multiple reflections, it may be difficult or even impossible to determine the maximum value E of the echo function A(tof) corresponding to the reflection at the interface 1 when the full measurement range FR is applied. L The full measuring range FR is Figure 3 The double arrow in FIG. 1 is indicated by a double arrow from the maximum height h included in the full measuring range FR. max The minimum flight time t min extends to the minimum height h included in the full measuring range FR min The maximum flight time t max By limiting the range to the limited measuring range LR, this situation is significantly improved, since all amplitude peaks E1, E2, E5 occurring outside the limited measuring range LR can be excluded. As an option, the maximum E corresponding to the reflection at interface 1 L Then it can be determined, for example, as the first amplitude peak value E3 or the maximum value of the amplitude peak values ​​E3 having the highest peak amplitude within the limited measurement range LR. Figure 3 In the example shown, the maximum value of the amplitude peak E3 will be identified as the maximum value E caused by the reflection at interface 1. L In addition or alternatively, it is suitable to identify the maximum E corresponding to the reflection at the interface 1 L Other methods can be applied within the limited measurement range LR. Further limiting the range to the limited measurement range LR also allows the signal-to-noise ratio and the amplitude resolution to be improved.

[0149] Even if the process variables v1,…,v are measured by a group of measuring devices n The measurement of the interface height h m The comparison can be expected to be extremely reliable, but this may change, for example due to an unexpected failure of one of the measuring devices. Therefore, as an additional option, the method according to the invention can be performed by at least once calculating and providing the process variable v i At least one calculated value v ci To further improve. Based on these calculated values ​​v ci, when the measured process variable vi and the corresponding calculated value v ci When the deviation between the measured process variables v exceeds a predetermined threshold, for example a threshold determined based on the inherent uncertainty of the calculation, the error in the measurement of the corresponding process variable v is detected and indicated, for example by issuing a corresponding notification. i Problems with the measuring equipment.

[0150] As an example, calculate the value v ci It can be determined, for example, based on a physical and / or statistical model for the process variables v1, ..., v based on other measurements. n Some or all of the above or based on the measured interface height h m and other measured process variables v1,…,v n to estimate the corresponding process variable v i With regard to the modules for estimating the interface height h, for example based on some or all of the training data, these models are preferably determined in the same way as described above.

[0151] Additionally or alternatively, the calculation unit 35 is designed to learn the corresponding process variable v i The calculated value v ci , where each calculated value v ci is based on other measured process variables v1,…,v n Some or all of the above or based on the measured interface height h provided to the calculation unit 35 m and other measured process variables v1,…,v n Some or all of the calculations are done by c The learning process of the calculation of the learning process is based on all measured process variables v1,..,v n or based on all provided measured process variables v1,..,v n and the measured interface height h m This learning process can be performed in the same way as described above with respect to the calculated interface height h c The computation of learning is performed in the same way. Likewise, some or all of the same training data can be used.

[0152] 1 Interface

[0153] 3 Upper level

[0154] 5 Lower level

[0155] 7 Container

[0156] 9 Concentrator

[0157] 11 Supply pipe

[0158] 13 Overflow outlet

[0159] 15 Overflow outlet

[0160] 17 Overflow outlet pipe

[0161] 19 Overflow outlet pipe

[0162] 21 Pump

[0163] 23 Rake

[0164] 25 Storage

[0165] 27 Supply lines

[0166] 29 Transducer

[0167] 31 Motor

[0168] 33 Parent Unit

[0169] 35 Computational Units

[0170] 37 Edge Devices

Claims

1. A method for determining the interface height of an interface (1) between an upper layer (3) and a lower layer (5) comprised in a container (7) of a concentrator (9), wherein the concentrator (9) is designed to perform a concentrating process, wherein: Particles suspended in a medium supplied to the container (7) are separated from liquid in the medium, and wherein the upper layer (3) comprises liquid floating on a lower layer (5), the lower layer comprising the particles, the method comprising the following method steps: measuring the interface height with an interface level measuring device (L) mounted on the concentrator (9) during a period of time when the conditions prevailing in the concentrator (9) allow the measurement to be carried out, measuring process variables related to the concentration process performed by the concentrator (9) using a set of measuring devices installed on the concentrator (9), and performing at least one calculation based on the measured process variables using a calculation unit (35) and providing a calculated interface height, Wherein, the calculation unit (35) is designed to learn the calculation of the calculated interface height based on the measured interface height and measured process variables measured and provided by the interface level measurement device (L) and the group of measurement devices during at least one of the time periods. The method of claim 1 , wherein the method is a computer-implemented method.

3. The method according to claim 1, wherein: The learning of at least one of the calculated interface heights is performed by the computing unit (35), the computing unit (35) performing a learning process based on training data, the training data being determined as measured interface heights and measured process variables measured and provided by the interface level measurement device (L) and the set of measurement devices during at least one of the time periods, or the training data being based on measured interface heights and measured process variables measured and provided by the interface level measurement device (L) and the set of measurement devices during at least one of the time periods; as well as Only the measured interface height and the measured process variables during one or more time intervals during which the measured interface height is reliable are used as training data or are used to determine the training data.

4. The method according to any one of claims 1 to 3, wherein: The reliability or unreliability of the measured interface height is determined by at least one of the following: a) monitoring the measured interface height, b) determining, based on said measured interface height, a rate of change of said interface height as a function of time and, based on said rate of change, determining that the measured interface height determined during a time interval in which said rate of change exceeds a predetermined threshold or exceeds a threshold given by a maximum rate of interface height expected during performance of said concentration process is unreliable, c) determining that a measured interface height outside a predetermined height range or outside a range of interface heights expected during normal performance of said enrichment process is unreliable, d) monitoring a signal-to-noise ratio of a measurement signal obtained by the interface level measurement device (L) and identifying a measured interface height determined based on a measurement signal having a signal-to-noise ratio less than a predetermined threshold as unreliable, e) applying a filter to the measured interface height, determining noise superimposed on the filtered interface height based on the measured interface height and the filtered interface height, and identifying the measured interface height as unreliable when the noise exceeds a predetermined threshold, f) performing a reference measurement of said interface height and identifying a measured interface height that deviates from a corresponding reference measurement by more than a predetermined threshold as unreliable, g) determining at least one of: at least one physical model for estimating the interface height based on at least one of the measured process variables and a statistical model for estimating the interface height based on at least one of the measured process variables, and based on the estimated interface height determined based on at least one of the physical model or the statistical model, performing at least one of the following: g1) identifying as unreliable a measured interface height which deviates from a corresponding estimated interface height by more than a predetermined threshold or by more than a threshold determined based on an inherent uncertainty of said estimate, g2) identifying unreliable measured interface heights included in training data determined for learning said calculation of said calculated interface height, and eliminating the identified unreliable measured interface heights from said training data, and g3) Providing notification of an unreliable measured interface height identified based on said estimated interface height.

5. The method according to any one of claims 1 to 3, comprising at least one of the following method steps: a) determining training data for learning the calculation of said calculated interface height by performing outlier detection in addition or as part of a machine learning process, identifying outliers included in said training data based on this outlier detection, and eliminating said identified outliers from the training data used for learning said calculation, and b) determining a value of at least one of the process variables based on at least one of the measured process variables or based on the measured interface height and at least one or both of the measured process variables, wherein: The determined value includes at least one of: at least one determined value determined by interpolation, at least one determined value determined by simulation, at least one determined value determined by Monte Carlo simulation, and performing at least one of the following: applying the values ​​determined for times included in at least one of the time periods or time intervals during which measured interface heights and measured process variables used for determining training data for learning the calculation of the calculated interface height were measured as additional training data, and In addition to the measured process variables, values ​​determined for a time occurring after learning for the calculation of the calculated interface height has been completed are applied to calculate the calculated interface height.

6. The method according to any one of claims 1 to 3, comprising the following method steps: Determine at least one secondary variable or at least one secondary variable directly or indirectly related to the interface height based on at least one of the measured interface height and at least one or all of the measured process variables; and perform at least one of the following: a) using a secondary variable determined for a time included in at least one of said time periods or time intervals during which a measured interface height and a measured process variable used for determining training data for learning the calculation of said calculated interface height were measured as additional training data, and b) Applying, in addition to the measured process variables, a secondary variable determined for a time occurring after the learning of the calculation of the calculated interface height, to calculate the calculated interface height.

7. The method according to any one of claims 1 to 3, comprising the following method steps: for at least one of the process variables, performing at least one of the following method steps: calculating and providing a calculated value of the process variable at least once, and detecting and indicating a problem with a measurement device measuring the process variable when a deviation between the process variable measured by the measurement device and a corresponding calculated value exceeds a predetermined threshold or exceeds a threshold determined based on an uncertainty inherent in the calculation; The calculated value of the process variable includes at least one of the following: a) at least one calculated value determined based on a physical model or a statistical model for estimating a corresponding process variable based on some or all of the other process variables measured by the measuring device or based on the measured interface height and some or all of the other process variables measured by the measuring device, and b) at least one calculated value calculated by the calculation unit (35), wherein: b1) the calculation unit (35) is designed to learn the calculation of the calculated value of the process variable based on the measured process variable or based on the measured process variable and the measured interface height; as well as b2) Each of the calculated values ​​of the corresponding process variables is calculated based on some or all of the other process variables measured and provided by the measuring device or based on the measured interface height and some or all of the other process variables measured and provided by the measuring device.

8. The method according to claim 3, wherein: At least one of the measured interface height, at least one of the measured process variables, and some or all of the training data is provided to the computing unit (35) by at least one of: a) the interface level measuring device (L) and at least one measuring device included in the set of measuring devices; b) a superordinate unit (33) connected to and / or communicating with at least one or all of: the interface level measuring device (L) and at least one measuring device included in the set of measuring devices, and c) an edge device (37) connected to and / or communicating with at least one or all of: the interface level measurement device (L) and at least one measurement device included in the set of measurement devices.

9. The method according to any one of claims 1 to 3, wherein: The process variable and the interface height are related.

10. The method according to any one of claims 1 to 3, wherein: The set of measuring devices that measure and provide the process variables includes at least one of the following: a flow meter F1 installed in or on a supply pipe (11) that supplies the medium to the container (7), the flow meter F1 measuring the flow rate of the medium supplied to the container (7), a flow meter F2 installed in or on the overflow outlet pipe (17) and measuring the flow rate of liquid drawn from the container (7) through the overflow outlet pipe (17), and a flow meter F3 installed in or on an overflow outlet pipe (19) connected to an overflow outlet (15) located at or near the bottom of the container (7), the flow meter F3 measuring the flow rate of sediment discharged from the container (7) through the overflow outlet pipe (19), a flow meter F4 installed in or on a supply line (27) supplying a product to the container (7), the product being a product including at least one of a coagulant and a flocculant, the flow meter F4 measuring a flow rate of the product supplied to the container (7) through the supply line (27), a density measuring device D1 which measures the density of the sediment located at or near the bottom of the container (7), a density measuring device D2, which is installed in or on the downflow outlet pipe (19) and measures the density of the sediment discharged from the container (7) through the downflow outlet pipe (19), a pressure measuring device (P) which measures the static pressure of the fluid prevailing at a predetermined height inside the container (7) or at or near the bottom of the container (7), a torque measuring device for measuring the torque applied by a motor (31) which causes a rake (23) mounted on the concentrator (9) to rotate about a longitudinal axis of rotation, wherein the rake (23) is a rake for pushing the sediment toward an overflow outlet (15) at the bottom of the container (7), a height measuring device (H) which measures the insertion height of the rake (23) relative to a predetermined reference height, a turbidity measuring device (O) mounted in or on the overflow outlet pipe (17) for measuring the turbidity of the liquid drawn from the container (7) through the overflow outlet pipe (17), and At least one other measuring device that measures at least one other process variable.

11. The method according to any one of claims 1 to 3, further comprising the following method steps: during at least one time interval in which the interface height measured by the interface level measurement device (L) is unavailable or unreliable: calculating a calculated interface height based on the measured process variable, and Perform at least one of the following: provide the calculated interface height and perform at least one of the following: monitor, adjust and control the concentration process performed on the concentrator (9) based on the calculated interface height.

12. The method according to any one of claims 1 to 3, further comprising the following method steps: During at least one or all of the time periods in which the measurement of the interface height is allowed and performed by the interface level measuring device (L): determining the calculated interface height, and Perform at least one of the following operations: provide the calculated interface height and perform at least one of the following: monitor, adjust and control the concentration process performed on the concentrator (9) based on at least one of the measured interface height, the calculated interface height and the average of the measured interface height and the calculated interface height.

13. The method according to any one of claims 1 to 3, further comprising the method steps of determining the calculated interface height and performing at least one of the following operations during at least one or all of the time periods in which the measurement of the interface height is allowed and performed by the interface level measurement device (L): monitoring the interface level measuring device (L) and the computing unit (35) based on the measured interface height and the calculated interface height, A fault is detected when a deviation between one of the measured interface heights and the corresponding calculated interface height exceeds a predetermined threshold, and When a fault is detected, a notification is provided to inform of the fault.

14. The method according to any one of claims 1 to 3, further comprising at least one method step: providing one of said calculated interface heights as a reference height for interface height measurement, determining a restricted measuring range (LR) including the reference height for the interface level measurement device (L) based on the reference height, and measuring the interface height within the limited measuring range (LR) using the interface level measuring device (L), in, The limited measurement range (LR) is determined as a portion of the full measurement range (FR) of the interface level measurement device (L), or is determined as a range including an interface height deviation from the reference height by less than a predetermined percentage, less than 10% or 5% of the width of the full measurement range (FR).

15. The method according to claim 14, in, The interface level measuring device (L): is a time of flight measurement device that determines the measured interface height based on the flight time required for a signal to travel to the interface (1) and for the signal to reflect back, and The invention comprises a signal processing and evaluation unit, which determines an echo function (A(tof)) which represents the signal amplitude of an echo signal as a function of a flight time (tof), identifies a maximum value (E) of the echo function (A(tof)) caused by a reflection at the interface (1) L ), and based on the maximum value (E L ) appears in the flight time (t EL ) determine the measured interface height, and The measurement of the interface height performed within the limited measurement range (LR) is performed by at least one of the following operations: excluding all amplitude peaks (E1, E2, E4, E5) comprised in the echo function which occur outside the restricted measurement range (LR), The maximum value (E) corresponding to the reflection at the interface (1) L ) is determined as the maximum value of the amplitude peak value (E3) within the limited measurement range (LR) having the highest peak amplitude comprised in the echo function (A(tof)), and The method is performed to identify the maximum value (E) of the echo function (A(tof)) caused by the reflection at the interface (1) within the limited measurement range (LR). L ) method.

16. A computer-readable medium having a computer program stored thereon, the computer program being used to determine the interface height of an interface (1) between an upper layer (3) and a lower layer (5) included in a container (7) of a concentrator (9) according to a method according to any one of claims 1 to 15, the computer program comprising instructions which, when the program is executed by a computer, cause the computer to implement the method according to any one of claims 1 to 15.

17. The computer readable medium of claim 16, wherein the computer program is used to determine at least one calculated interface height.

18. The computer-readable medium of claim 16, wherein the instructions include instructions that, when the program is executed by a computer, cause the computer to perform learning of the calculation based on the measured interface height and the measured process variables and to perform calculation of the at least one calculated interface height based on the learned calculation and the measured process variables.

19. A computer program product, comprising a computer program and at least one computer-readable medium, wherein the computer program is used to determine the interface height of the interface (1) between an upper layer (3) and a lower layer (5) included in a container (7) of a concentrator (9) according to a method according to any one of claims 1 to 15, wherein at least the computer program is stored on the computer-readable medium.

Images