DEVICE AND METHOD FOR MONITORING A MIXING PROCESS

Abstract

The present invention relates to a device for preparing a medical solution by mixing at least one liquid and at least one concentrate raw material, comprising a mixing container into which the at least one liquid and the at least one concentrate raw material can be fed, a control device, and a measuring device for measuring at least one parameter, preferably a density, of a mixture produced by means of the device during the mixing operation, and a corresponding method.

Claims

1. Device for preparing a medical solution by mixing at least one liquid and at least one concentrate raw material, by means of or in a mixing container into which the at least one liquid and at least the one concentrate raw material can be fed, a control device, and a measuring device for measuring a parameter, preferably a density, of a mixture produced by means of the device during the mixing operation, wherein the measuring device is configured to carry out measurements continuously and/or online during a mixing operation carried out by means of the device.

2. Device according to claim 1, wherein the control device is configured to control or regulate the operation of the device, in particular a mixing operation carried out by it, on the basis of the parameter values generated by means of the measuring device and/or on the basis of trend analyses performed by it.

3. Device according to claim 1, wherein the control device is configured to compare the parameter values measured by the measuring device with a setpoint value and, when the setpoint value or a tolerance range surrounding it is reached, to terminate a mixing operation carried out by means of the device and/or to issue an output to a user.

4. Device according to claim 1, wherein the control device is configured to operate the device for a first predetermined time span for carrying out a mixing operation and, after elapse and/or during the predetermined first time span, to compare the parameter values measured by the measuring device preferably continuously and/or online, with a setpoint value and, if the setpoint value or a tolerance range surrounding it is not reached, to prolong the mixing operation once or multiple times by a second predetermined time span and/or to issue an output to a user, with which the user is preferably requested to approve or instruct the prolongation of the mixing operation and/or to approve the mixture.

5. Device according to claim 1, wherein the control device is configured to discard a mixture produced by means of the device and/or to issue an output to a user that the produced mixture is to be discarded, if the parameter values measured continuously and/or online by the measuring device do not reach a setpoint value or a tolerance range surrounding it after a time span for carrying out a mixing operation has elapsed, and/or if a time course of the measured parameter values does not or not sufficiently approach or deviate from the setpoint value or the tolerance range during a predetermined time interval during the mixing operation.

6. Device according to claim 1, wherein the measuring device is a flexural resonator through which the mixture produced by means of the device preferably flows continuously.

7. Device according to claim 1, wherein the measuring device is or comprises a device for measuring on the basis of a selective ion concentration, a device for measuring density by means of a volumetric measuring chamber and or a mass, a device for measuring density by means of ultrasound or gamma rays, a device for measuring density by means of the Coriolis principle and/or a device for optical density measurement or for density measurement by means of refraction.

8. Device according to claim 1, wherein the control device is further configured to electronically document the parameter values determined by means of the measuring device as well as preferably their time histories, preferably to file them in an electronic logbook and/or to transmit them to a further device, preferably to a master display or a central database system.

9. Method for monitoring a mixing operation for preparing a medical solution by mixing at least one liquid and at least one concentrate raw material, wherein the mixing operation is preferably carried out by means of a device according to any one of the preceding claims, comprising the step of: measuring a parameter, preferably a density, of a mixture produced by means of the device during the mixing operation, preferably by means of a measuring device associated with the device carrying out the mixing operation.

10. Method according to claim 9, wherein measuring the parameter is carried out continuously and/or online.

11. Method according to claim 9 further comprising the step of: controlling or regulating the operation of the device, in particular a mixing operation carried out by said device, on the basis of the parameter values detected by means of the measuring device.

12. Method according to claim 10, further comprising the step of: using the parameter values detected by means of the measuring device in the context of a predictive maintenance of the device, in particular for determining and/or scheduling times for repairs, the replacement of components and/or recalibrations.

Description

[0050] Further advantages, features and effects of the present invention result from the following description of preferred embodiments with reference to the Figures, in which the same reference characters indicate identical or similar components or method steps. Shown are in:

[0051] FIG. 1 a flow chart of a method according to the invention;

[0052] FIG. 2 a flow chart of another method according to the invention;

[0053] FIG. 3 a flow chart of yet another method according to the invention;

[0054] FIG. 4 a flow chart of another method according to the invention;

[0055] FIG. 5 a flow chart of still yet another method according to the invention;

[0056] FIG. 6 a flow chart of yet another method according to the invention; and

[0057] FIG. 7 a device according to the invention.

[0058] As shown in FIG. 1, a mixing operation of at least one concentrate raw material and at least one liquid or solvent is started in step S1. Thereafter, in a generally optional step S2, the function of the measuring device, in this case a density sensor, is checked, for example using a reference liquid or permeate.

[0059] Optionally, a predetermined time span, e.g. 10 minutes, can then be waited in step S3 before starting the preferably continuous measurement of the density of the produced mixture during the mixing operation in step S4. With the waiting period in step S3, it can be avoided, for example, that measurements are made at a time when the mixture most likely does not meet the target specifications. In addition, it avoids measurement inaccuracies at the beginning of the mixing operation.

[0060] The measurement in step S4 takes place continuously during the mixing operation, which means that the mixing operation can be monitored particularly accurately and without gaps.

[0061] In step S5, it is checked whether the measured values from step S4 correspond to a setpoint value, i.e. whether a target density has been reached. If this is the case, a notification is sent to a user in step S6 and the produced mixture is transferred to a stocking system, for example a barrel or tank, in step S7.

[0062] An optional additional waiting time of, for example, 10 minutes may be provided between steps S5 and S6 to avoid operating at the absolute minimum target density. If such an additional waiting time is provided, the density of the mixture is expected to continue to increase beyond the achieved minimum target density during a proper mixing operation.

[0063] Then, in step S8, it is waited whether the notified user approves the mixture or the medical solution. If this is the case, the medical solution is approved and used for its final application in step S9.

[0064] If it is detected in step S5 that the measured values from step S4 do not correspond to the setpoint value, the mixing operation is continued in step S10 until a predetermined time span, for example 70 minutes, has elapsed.

[0065] Within this predetermined time span, steps S4 and S5 may be carried out regularly at predetermined intervals to check whether the entire 70 minutes of mixing are actually required for obtaining a desired medical solution or its parameter target values or target value ranges.

[0066] The time span at step 10 can be different for the first cycle through the loop with steps S4, S5 and S10 than for the second, third, each further cycle and can be, for example, 70 minutes for the first cycle and 30 minutes for each further cycle. The values mentioned are examples, arbitrary other values are conceivable.

[0067] After the predetermined time span of step S10 has elapsed, the system optionally waits for a user input in step S11 for a certain time span, e.g. 10 minutes. The length of this time span can be set as desired.

[0068] If a corresponding user input is made or if no input is made, it is decided in step S12 as to whether the mixing operation is to be continued for a second predetermined time span. The mixing operation can be automatically prolonged if there is no user input. The predetermined time span is e.g. 30 minutes.

[0069] If it is decided in step S12 that the mixing operation should be continued, the density is then measured again according to step S4. If it is decided in step S12 that the mixing operation is not to be continued, the mixture is either transferred to the stocking system for manual sampling according to step S13 or discarded according to step S15.

[0070] An optional request for approval by a user may be interposed between steps S12 and S13. For example, if a user decides in step S12 that mixing should not be prolonged, or a predetermined maximum time span of execution of the mixing operation or maximum number of prolongations is reached and/or the control device of the device decides that mixing should not be prolonged, then a request can be issued to the user whether the mixture or the medical solution, i.e. the contents of the receiver tank (also referred to as mixing tank) should be transferred to a stocking device or not.

[0071] If the manual sampling in step S14 shows that the mixture meets the target specifications, the process proceeds according to step S8. If the mixture does not meet the target specifications, it is discarded in step S15.

[0072] As a final step, the mixing device is rinsed with permeate or another suitable rinsing liquid in step S16 and is thus provided for the next mixing operation.

[0073] Alternatively, step S16 can occur prior to or partially simultaneously with step S15.

[0074] FIG. 2 shows a flow chart of a method according to the invention, which is reduced in the number of method steps compared to the method in FIG. 1.

[0075] FIG. 3 shows a flow chart of a method according to the invention, which is based on the method according to FIG. 2, but additionally includes step S2.

[0076] As can be seen from the flow chart shown in FIG. 4, after a target density has been determined in step S5, the approval of a user can first be waited for in step S8 before the mixture or the medical solution is transferred to the stocking device in step S7 if the approval has occurred. Alternatively, in step S8, the approval may occur automatically, for example by a device according to the invention, if it has been detected in step S5 that the mixture corresponds to the target medical solution. In other words, for example, if the mixture meets the target specifications, i.e. is the desired medical solution, the mixture is approved.

[0077] As shown in FIG. 5, a method according to the invention can be executed automatically without requiring user input. For example, in this embodiment, if it has been detected in step S5 that the target density has not been achieved and it has been detected in step S10 that the first time span of the mixing operation, in this example 70 minutes, has elapsed, the mixing operation may be automatically prolonged in step S12 once or multiple times by a predetermined second time span until either the target density has been reached or, for example, due to the expiration of a certain maximum time span, the mixture is discarded in step S15. In other words, for example, if the mixture does not meet the target specifications, i.e. does not correspond to the desired medical solution, the mixture is discarded.

[0078] FIG. 6 shows a flow chart of a further method according to the invention. In this embodiment, between step S7, in which the mixture is supplied to the stocking device because the mixture corresponds to the desired medical solution, and step S8, in which an approval of the mixture by the user is waited for, a step S18 is provided, in which it is detected whether the mixture or the medical solution has been completely supplied to the stocking device and the transfer to the stocking device has thus ended.

[0079] After a positive user approval in step S8, the mixture or the medical solution is fed to its application, e.g. as dialysate concentrate. In addition, the device is rinsed with permeate or another liquid in step S16.

[0080] In addition, in this embodiment, after a decision has been made in step S12 against prolongation of the mixing operation, a decision is made in step S17 as to whether the mixture should be transferred to the stocking system. If a positive decision is made in step S17, the mixture is transferred to the stocking system in step S7, and a check is made in step S18 to determine whether the transfer has ended.

[0081] If a negative decision is made in step S17, a decision is made in step S24 as to whether the mixture should be discarded. If it is decided that the mixture should not be discarded, the method proceeds to step S12. If it is decided in step S24 that the mixture should be discarded, it is discarded in step S15.

[0082] After step S15 or S18, a sample of the mixture is taken according to step S19 and tested in step S20 (for example with an alternative measuring device), for example by a manual density measurement. In step S21, it is determined whether the measured values determined in step S20 correspond to a target specification.

[0083] If it is determined in step S21 that the measured values determined in step S20 do not meet the target, the mixture from the stocking system is discarded in step S22.

[0084] If it is determined in step S21 that the measured values determined in step S20 correspond to the target specification, a user is requested in step S23 to confirm the approval of the mixture. Only if the confirmation is positive is the mixture supplied to its final intended use as a medical solution; if no approval is given, the user waits for one.

[0085] Thus, the measurement and evaluation in steps S19-S21 and the approval in step S23 provide an additional level of safety before the mixture is released from the stocking system for its final use.

[0086] FIG. 7 shows a device 1 according to the invention for preparing a medical solution by mixing at least one liquid and at least one concentrate raw material by means of an arbitrary mixing operation with or in a mixing container 2, into which the at least one liquid and the at least one concentrate raw material can be fed, a control device 3 and a measuring device 4 for measuring at least one parameter, preferably the density, of a mixture produced by means of the device 1 during the mixing operation. The device 1 preferably has two containers 5, which contain the same produced medical solution and stock it redundantly and are connected to the mixing container 2 via a line 6. For example, the containers 5 serve to store the produced dialysate concentrate. Fluid, for example permeate, is supplied to the mixing container 2 via a line 7. The concentrate raw material can be supplied to the mixing container via line 8. Any raw material container with concentrate raw material can be connected to line 8.