DEVICE FOR THE REGENERATION OF USED DIALYSIS SOLUTION

Description

[0001] The present invention relates to a device and a method for producing a dialysis solution.

[0002] It is known from the prior art to supply dialysis machines with a ready-to-use dialysis solution, e.g. from a line system that is connected to a central facility for producing the dialysis solution and that is generally designed to supply a plurality of dialysis machines with dialysis solution. Alternatively, it is possible to produce the dialysis solution on the dialysis machine itself, i.e. in a decentralized manner. For this purpose, an RO system (RO = reverse osmosis) for producing ultrapure water can be provided, which can be part of the dialysis machine or designed as a separate unit. The ultrapure water is mixed with one or more concentrates in the dialysis machine to obtain a ready-to-use dialysis solution for treating the patient.

[0003] The large amount of water required for this type of dialysis solution preparation means that conventional dialysis machines require an additional RO system, making the overall systems comparatively large and heavy, making transporting the machines difficult. This disadvantage is particularly important, for example, in home hemodialysis and portable devices designed to allow patient mobility during treatment.

[0004] Figure 5 shows a conceivable possibility, not falling within the scope of the present invention, of an embodiment of a dialysis machine in which water consumption is reduced by obtaining new, i.e. ready-to-use, dialysis fluid using used dialysis fluid, which leads to a reduction in water consumption.

[0005] Reference symbol I denotes the inlet for fresh water into the container 10; the inlet line can be shut off by a valve V1. O denotes the outlet from the container 10 for used solution; the outlet line can be shut off by a valve V2. The container 10 is also referred to below as the water inlet chamber. In principle, a container 10 with a stationary water connection or any other container, such as a bag, can be used. The container 10 can have rigid or flexible walls.

[0006] Reference numeral 100 denotes a dialyzer, which preferably has a plurality of membranes, preferably a membrane bundle, through which dialysate flows on one side D and blood flows on the other side B. The dialysis solution that has flowed through the dialyzer 100 and is thus loaded with contaminants from the blood is referred to as used dialysis solution or used dialysate. The used dialysate, which is fed from the dialyzer 100 through line 40 back into the water inlet chamber 10, is sucked in by a pump 50 and pumped into an upstream circuit, which is a first circuit.

[0007] This circuit essentially comprises the pump 50, the tank 10, the primary side of the filter 20, i.e., the section upstream of the filter membrane or other filter medium, and the pressure relief valve 60, including the lines connecting these components. Reference numeral 30 designates the return line from the pressure relief valve 60 to the tank 10.

[0008] The pump 50 pumps the used dialysis solution from the container 10 to the primary side 21 of the filter 20 and the retentate back into the container 10 via the valve 60. This creates a pressure drop across the valve 60 and thus also a pressure on the filter 20. This pressure or pressure drop can be adjusted by the valve 60 and thus matched to the ideal operating point of the filter 20.

[0009] The pressure gradient between the primary side 21 and secondary side 22 of the filter 20 results in a flow through the filter membrane or other filter medium, with the filtrate on the secondary side 22, i.e., downstream of the filter medium, present in the form of ultrapure water. It enters the mixing device 200, which can be designed as a mixing circuit, mixing container, pipe section, etc.

[0010] In the mixing circuit or mixing container 200, etc., the ultrapure water is mixed with one or more concentrates, such as a basic and an acidic concentrate. The dialysis solution can also be heated or reheated there to minimize the amount of heat removed from the blood in the dialyzer 100 by the dialysis solution. A second circuit thus comprises the secondary side 22 of the filter 20, the mixing device 200, the dialysate side D of the dialyzer 100, and a line system connecting these components, with a line leading from the dialysate side D of the dialyzer 100 back into the water inlet chamber 10.

[0011] As from Figure 5 As can be seen, the first and second circuits are two closed, cascaded water and liquid circuits. In principle, more than two of these circuits can be present.

[0012] Filter 20 can optionally be based on graphene filter technology, allowing the ultrapure water to be separated from the filter without, for example, dissolved oxygen. This eliminates the need for additional components in the dialysis machine, such as a separate degassing circuit.

[0013] By "flushing" the filter 20 on its primary side 21 via the valve 60, high performance can be achieved and fouling of the filter 20 can be prevented or delayed. This increases the service life of the filter 20. Additionally, the filter 20 can be flushed by the valve 90 short-circuiting the pressure relief valve 60. In this case, the fluid bypasses the valve 60 and enters the bypass containing the valve 90, and from there, flows back into the container.

[0014] How this further Figure 5As can be seen, a fill level sensor 110 is located in the tank 10. If this sensor signals that the fill level in the tank 10 has fallen below a limit value, a leak can be concluded, since both the first and second circuits are closed and thus the fill level should remain the same. Valves V1 and V2 are closed during normal operation, ie, when no water change is taking place.

[0015] Out of Figure 5This also results in the presence of a conductivity measuring cell 70 downstream, i.e. downstream of the pump 50. This makes it possible to measure the concentration of the contaminated fluid caused by the circuit operation, and it can be deduced when the water in the circuit should be completely replaced (fresh water timing). This exchange can be carried out using the valves V1 and V2 and volumetrically balanced with the help of the level sensor 110 in the container 10. During normal dialysis operation, the valves V1 and V2 are closed, which means that the level sensor 10 can also be used for leak monitoring, as described. If one of the two closed circuits loses fluid, this can be detected by the level in the container 10. This serves patient safety.

[0016] The function of the filter 20 can be monitored using an additional conductivity measuring cell 80 downstream of, i.e., downstream of, the filter 20. As soon as significant damage to the filter membrane or other filter medium occurs, conductive ions pass through the filter 20, which in turn can be detected by the sensor 80. Optionally, the transmembrane pressure across the filter 20 can be monitored using the pressure sensor 102 located downstream of the filter 20 in order to detect any degradation or loss of filter performance.

[0017] Because the two circuits are closed, the energy required to heat the dialysate is significantly reduced. As a result, smaller heaters can be used than is the case with state-of-the-art devices. A heat exchanger is still an option for fresh water cycling, but can also be omitted for cost reasons. As explained above, the ultrapure water accumulating on the secondary side 22 of the filter 20 reaches the mixing section 200 of the machine, where it is enriched with, for example, bicarbonate and acid, so that ready-to-use dialysis fluid is available at the dialyzer 100 for exchange with the patient's blood. The reference symbol B / U designates the balancing unit and / or an ultrafiltration pump, which extracts a partial volume from the used dialysis fluid corresponding to the physician's prescription.

[0018] The two-stage (cascaded) filter approach allows for the removal of toxins larger than water from the patient. These substances, including ions such as Na and Cl from the dialysis fluid, are then concentrated in container 10 and discharged via the outlet O during the fresh water cycle. Ultrafiltration is still performed, for example, via a UF pump in the B / U unit, which pumps directly into the drain. Since these are closed circuits, the advantages of volumetric balancing, as is currently achieved, for example, with the help of a balancing chamber, can be maintained.

[0019] Due to the properties of the filter 20, which are impermeable to gases, this design eliminates the need for additional degassing measures / devices. Alternatively, depending on the filter used, a degassing throttle / device can be introduced into the upstream, i.e., first, circuit, as indicated by reference symbol E in Figure 5 However, a separate chamber can also serve as an air separation chamber, which can be between 20 and 60 cm Figure 5 can be arranged.

[0020] At this point it is pointed out that all of the Figure 5 explained features may be the subject of the present invention individually or in combination. It is further noted that the same reference numerals in Figure 5 as well as in the Figures 1 to 4 identify identical or functionally equivalent elements.

[0021] The order according to Figure 5has the disadvantage that the solution in the container 10 becomes more concentrated over time. Thus, the solution present on the primary side 21 of the filter 20 also becomes increasingly more concentrated with the duration of the treatment. The osmotic pressure generated by this solution complicates filtration in the filter 20, as it counteracts the formation of filtrate. With increasing concentration on the primary side 21, increasing pressure generated by the pump 50 is therefore necessary to obtain a sufficient amount of ultrapure water on the secondary side 22 of the filter 20. Devices belonging to the prior art are described in the documents WO 2014 128293 and WO 2015 / 124716.

[0022] The present invention is based on the object of providing a device with which efficient ultrapure water production is possible.

[0023] This object is achieved by a device having the features of claim 1.

[0024] According to this, the device for producing a dialysis solution comprises a first circuit and a second circuit, wherein the first circuit comprises a container for receiving the used dialysis solution or fresh water or another liquid, the primary side of a filter connected downstream of the container, and a return line from the primary side of the filter into the container, wherein the filter is designed to produce purified water from the used dialysis solution or from fresh water or from another liquid, and wherein the second circuit comprises the secondary side of the filter, the dialysate side of a dialyzer, a reservoir, a line leading from the reservoir to the secondary side of the filter, which is also referred to below as a concentrate line, by means of which dialysate or a dialysate concentrate can be supplied to the secondary side of the filter, and a filtrate line.which leads away from the secondary side of the filter.

[0025] According to one embodiment, the reservoir accommodates concentrates such as a bicarbonate concentrate or an acidic concentrate or a ready-to-use dialysis solution or a mixture of a basic concentrate, in particular a bicarbonate concentrate, and an acidic concentrate.

[0026] In contrast to the Figure 5 In the arrangement shown, a solution is fed to the secondary side of the filter, either in the form of a ready-to-use dialysis solution or, preferably, in the form of a liquid concentrate. This has the advantage that the osmotic pressure gradient across the filter membrane decreases accordingly, thus enabling more efficient filtrate production.

[0027] Preferably, the concentrate supplied to the secondary side of the filter is a concentrate required for the preparation of the dialysis solution, and particularly preferably a bicarbonate-containing concentrate. It is particularly preferred if the concentrate contains only a single conductive component, such as bicarbonate, in addition to water and optionally sodium chloride.

[0028] The filter's job is to produce purified water from the solution in the container, i.e. water whose content or concentration of impurities and other ingredients, such as ions or molecules, is lower than in the solution that is fed to the filter. The filter is preferably designed to produce ultrapure water, which in the context of the present invention is understood to mean water that is suitable for use in preparing a ready-to-use dialysis solution. The filter can be designed with one or more stages, with solution flowing through the multiple stages one after the other. The use of several filters connected in series is also conceivable in order to achieve the desired degree of water purity. The filter is preferably a hollow fiber or wound module, as used for RO (reverse osmosis) or FO (forward osmosis) processes.

[0029] The filter mentioned is preferably a graphene filter. This is understood to mean a filter which contains graphene or a graphene derivative, such as graphene oxide, as its filter material, or whose filter material consists of or contains these substances. Graphene or graphene oxide is gas-tight but at the same time permeable to water, which in the context of the present invention has the advantage that gas is not introduced from the first into the second circuit and thus into the ready-to-use dialysis solution. The present invention is not restricted to these filters, however, but also encompasses other filters which are preferably gas-impermeable but allow liquid to pass through. If the filter used does not have the property of gas-impermeability, then, for example,Air can be separated on the primary side through a degassing throttle, which can then be pumped back into the vessel via a valve (preferably a pressure-limiting valve) and thus removed. Other degassing processes are also possible.

[0030] The filter preferably has four connections, two of which are provided on the primary side and two on the secondary side.

[0031] In a preferred embodiment of the invention, a return line is provided from the dialysate side of the dialyzer to the container, through which used dialysis solution is supplied to the container. Alternatively, a return line can be provided from the dialysate side of the dialyzer to a drain, i.e., the used dialysis solution is discarded.

[0032] The filtrate line, which leads from the secondary side of the filter, can connect the secondary side of the filter to a balancing chamber of the device. In this case, the filtrate obtained through the filter, preferably ultrapure water, for example, is mixed with the concentrate, and this mixture is fed to the balancing chamber of the dialysis machine. If the concentrate is a bicarbonate solution, a bicarbonate solution diluted by the ultrapure water is fed to the balancing chamber. In a further step, the acidic concentrate can then be added to this mixture, or the diluted bicarbonate solution, etc., can be poured into a container, such as the reservoir, which already contains a defined amount of additional concentrate or other components necessary for the ready-to-use dialysis solution.

[0033] In a further embodiment, a concentrate consisting of the acidic and basic concentrates can be supplied directly to the filtrate side of the filter. The concentrate solution in this embodiment results in particularly favorable filtration performance of the filter. According to this embodiment, the dialysate concentrate comprises both a basic concentrate, in particular a bicarbonate concentrate, and an acidic concentrate.

[0034] It is also conceivable for the filtrate line to be fluidly connected to the reservoir, so that, for example, the filtrate obtained through the filter, preferably ultrapure water, is mixed with the concentrate, and this mixture is fed to the reservoir of the dialysis machine. The reservoir or mixing chamber is preferably located downstream of the balancing chamber.

[0035] Furthermore, it is conceivable that the reservoir contains ready-to-use dialysis solution or a concentrate, in particular a bicarbonate concentrate, which is used to produce a ready-to-use dialysis solution.

[0036] Preferably, the reservoir is a dialysate mixing device in which the ready-to-use dialysis solution is mixed and from there fed to the dialysate side of the dialyzer.

[0037] Preferably, a pump designed to supply a defined volume or flow rate to the secondary side of the filter is located in the concentrate line. The pump can be, for example, a volumetric pump or an eccentric diaphragm pump. This makes it possible to implement a purely volume-controlled mixing process, which can be monitored, for example, by an independent conductivity measurement.

[0038] Furthermore, it can be provided that a pump is arranged in the first circuit, preferably upstream of the primary side of the filter, to effect a flow of liquid in the first circuit. This pump conveys the liquid in the container to the primary side of the filter.

[0039] Alternatively or additionally, a pressure limiting device can be provided preferably downstream of the filter in the first circuit, by means of which pressure on the primary side of the filter can be adjusted.

[0040] To monitor or control the process carried out by the device, one or more sensors, preferably one or more conductivity measuring cells, can be arranged in the first circuit, located upstream and downstream of the primary side of the filter. Alternatively or additionally, one or more sensors, preferably one or more conductivity measuring cells, can be arranged in the concentrate line and / or the filtrate line in the second circuit.

[0041] Furthermore, it can be provided that one or more pressure measuring devices are arranged downstream of the secondary side of the filter and / or upstream of the primary side of the filter. This allows information to be obtained about the pressure conditions in the respective circuit as well as about the transmembrane pressure across the filter membrane.

[0042] Furthermore, the device can have an ultrafiltrate pump for removing dialysis solution, preferably from the return line from the dialyzer to the container and / or a balancing chamber for the balanced supply and removal of dialysis solution to and from the dialyzer.

[0043] The first and / or second circuits can be closed or open. "Open" means that there is no circuit in the strict sense, but rather a fluid system that has a drain at at least one point, by means of which a liquid can be drained from the circuit and discarded.

[0044] The container can be designed as a bag, in particular as a flexible bag, and further in particular as a disposable article.

[0045] The claimed device may be a dialysis machine or form part of a dialysis machine or a device for mixing dialysis solution.

[0046] The present invention further relates to a method for producing a dialysis solution using a device according to the invention, wherein the solution from the container is fed to the primary side of the filter and the retentate is returned to the container, wherein a dialysis solution or a dialysate concentrate is fed to the secondary side of the filter and is mixed with the permeate of the filter on its secondary side.

[0047] Preferably, the dialysis solution or dialysate concentrate supplied to the secondary side of the filter is removed from said reservoir and fed to the secondary side of the filter.

[0048] In A pump can be arranged in the concentrate line, which supplies a defined volume or a defined volume flow of dialysis solution or dialysate concentrate to the secondary side of the filter.

[0049] Furthermore, it can be provided that the permeate accumulating on the secondary side of the filter is fed into the reservoir and / or into a balancing chamber together with the supplied dialysis solution or dialysate concentrate.

[0050] It should be noted here that the terms "a" and "an" do not necessarily refer to exactly one of the elements, although this is a possible interpretation, but can also refer to a plurality of the elements. Likewise, the use of the plural also includes the presence of the element in question in the singular, and conversely, the singular also encompasses several of the elements in question.

[0051] Further details and advantages of the invention are explained in more detail with reference to an embodiment shown in the drawing.

[0052] They show: Figure 1: a schematic flow diagram of a device according to the invention in a first embodiment of the invention, Figure 2: a schematic flow diagram of a device according to the invention in a second embodiment of the invention, Figure 3: a schematic flow diagram of a device according to the invention in a third embodiment of the invention, Figure 4: a schematic flow diagram of a device according to the invention in a fourth embodiment of the invention, Figure 5: a schematic flow diagram of a further device which is not the subject of the invention.

[0053] As stated above, Figure 5 shows a variant which is not the subject of the invention. Identical or functionally equivalent elements according to Figure 5 have the same reference numerals as in Figures 1 to 4 , so that with regard to the structure of the Figures 1 to 4 devices shown also on Figure 5 is referred to.

[0054] How this Figure 1 As can be seen, the Figure 1 The device shown is different from the arrangement according to Figure 5 Essentially, a line K runs from the reservoir 200 to the secondary side 22 of the filter, through which the ready-to-use dialysis solution flows. The conductivity sensor L2 is located in this line K.

[0055] On the drain side, a filtrate line F leads from the secondary side 22 of the filter 20 to the reservoir 200. This line carries a mixture of the dialysate supplied via line K with the ultrapure water obtained by the filter 20, e.g., using RO. Line F contains the conductivity sensor L4.

[0056] Furthermore, a line 52 is provided, which can be closed by valve V7 and through which the reservoir 200 is in fluid communication with the line through which fluid is supplied from the container to the primary side 21 of the filter 20. The latter line contains the pump 50 and the conductivity sensor L1. Accordingly, when the valve is open, the reservoir 200 is in fluid communication with the primary side 21 of the filter 20.

[0057] In a device according to Fig. 1 The mass transfer or volume transfer across the filter is measured and ensured by the conductivity sensors L2 and L4. Figure 2shows an embodiment in which a concentrate or a concentrate mixture, in particular a bicarbonate concentrate, is conveyed through line K. This is done by the pump 51 located in line K. A concentrated solution is thus conveyed to the secondary side 22 of the filter 20, the conductivity of which is determined by the conductivity sensor L2. A specific, i.e., defined, volume of this concentrate or mixture is conveyed by means of the pump 51. This concentrate or mixture is mixed in the filter 20 with ultrapure water, which dilutes the concentrate or concentrate mixture on the secondary side.

[0058] This mixture is fed to the balance chamber BK, which is designed with four valves and has two chambers separated by a movable partition, each of which has an inlet and an outlet valve.

[0059] Thus, the balance chamber BK receives the concentrate or concentrate mixture diluted with ultrapure water. This results in a purely volume-controlled mixing process, which can be monitored by an independent conductivity measurement (conductivity sensor L4). The conductivity contributes (in contrast to the design according to Figure 1 ) only the concentrate is included as one component of the ready-to-use dialysis solution. This allows an expected value for the conductivity to be calculated. Controlling to an expected value for the conductivity is easy to implement.

[0060] It is also conceivable to provide a control system or a control loop whose target value is the volume of diluted concentrate / concentrate mixture fed to the balancing chamber, with the actual value being provided by the conductivity measurement. The decisive factor here is the specific retention capacity of the filter. Knowing the conductivity in line K and the conductivity in line F, it is possible to determine the amount by which the volume delivered by the pump has increased due to the transfer of ultrapure water, i.e., the volume fed to the balancing chamber or the reservoir 200 downstream of it.

[0061] How this further Figure 2 As can be seen, the primary side 21 of the filter 20 or the lines leading from it are in fluid communication with the reservoir 200 via the line 96 in which the valve V5 is located.

[0062] The embodiment according to Figure 3differs from the variant according to Figure 2 by a total of four conductivity sensors L1 - L4, two of which are located upstream and downstream of the primary side 21 of the filter and two in the concentrate line K and in the filtrate line F. With knowledge of the inlet and outlet conductivity, the process can be further verified, controlled, and monitored.

[0063] Furthermore, pressure sensors S1 and S2 are provided to monitor the transmembrane pressure across the membrane of filter 20. Sensor S1 is located on the inlet side of the primary side of filter 20, and sensor S2 is located in the filtrate line F. The sensor values ​​can be used to detect degradation of filter F, e.g., through scaling, and to plan and execute filter flushing / regeneration cycles.

[0064] Sensor S2 can also detect whether sufficient ultrapure water has flowed through filter 20 to its secondary side 22 and whether the balancing chamber is full, so that the desired mixing ratio is achieved and the balancing chamber can be switched or cycled. A new "mixing cycle" can then be started by pump 51.

[0065] Alternatively, the evaluation of the torque or motor current of the pump 51 can be used to achieve the desired mixing ratio.

[0066] The value of the conductivity sensor L1 can be used to control the fresh water timing, ie to detect when the retentate in the container 10 needs to be replaced by fresh water.

[0067] The invention fundamentally encompasses not only the use of a single filter 20, but also the use of multiple filters connected in series, i.e., cascaded. This relieves the load on pump 50, but requires the presence of multiple pumps.

[0068] The chamber 10 can be designed as a rigid container or as a bag.

[0069] The filter 20 can be rinsed and cleaned by opening, for example, valves V3 and 90.

[0070] Alternatively, the secondary side can be initially filled with fresh water via valve V5 or V6. However, it is preferable to fill it with fresh water via filter 20 and the balancing chamber BK.

[0071] How this Figure 4As can be seen, the process can also be carried out without returning used dialysate to the container 10. In this case, the used dialysate is discarded via line 40'. The water supplied to the container 10 is preheated via the heat exchanger WT using the used dialysis solution.

Claims

1. Apparatus for preparing a dialysis solution, wherein the apparatus has a first circuit and a second circuit, wherein the first circuit comprises a container (10) for receiving the consumed dialysis solution or fresh water or another fluid, the primary side (21) of a filter (20) connected downstream of the container (10), and a return line (30) from the primary side (21) of the filter (20) into the container (10), wherein the filter (20) is configured to prepare purified water from the consumed dialysis solution or from fresh water or from another fluid, and wherein the second circuit comprises the secondary side (22) of the filter (20), the dialyzate side of a dialyzer (100), a reservoir (200), a line (K) that leads from the reservoir (200) to the secondary side (22) of the filter and by means of which dialyzate or a dialyzate concentrate can be supplied to the secondary side (22) of the filter (20), and a filtrate line (F) that leads away from the secondary side (22) of the filter (20).

2. Apparatus in accordance with claim 1, characterized in that a return line (40) from the dialyzate side of the dialyzer (100) into the container (10) is present; or in that a line (41') is present from the dialyzate side of the dialyzer (100) into a drain.

3. Apparatus in accordance with claim 1 or claim 2, characterized in that the filter (20) is a graphene filter.

4. Apparatus in accordance with any one of the preceding claims, characterized in that the filtrate line (F) leads from the secondary side (22) of the filter (20) to a balancing chamber (BK) of the apparatus and / or to the reservoir (200).

5. Apparatus in accordance with any one of the preceding claims, characterized in that ready-to-use dialysis solution or a concentrate, in particular a bicarbonate concentrate, is present in the reservoir (200) that is used to prepare a ready-to-use dialysis solution.

6. Apparatus in accordance with any one of the preceding claims, characterized in that the reservoir (200) is a dialyzate mixing device (200).

7. Apparatus in accordance with any one of the preceding claims, characterized in that a pump (51) is arranged in the line (K) and is configured to supply a defined volume or a defined volume flow to the secondary side (22) of the filter (20).

8. Apparatus in accordance with any one of the preceding claims, characterized in that a pump (50) is arranged in the first circuit, preferably upstream of the primary side (21) of the filter (20) to effect a flow of liquid in the first circuit; and / or in that a pressure relief device (60) by means of which pressure can be set on the primary side (21) of the filter (20) is provided in the first circuit, preferably downstream of the filter (20).

9. Apparatus in accordance with any one of the preceding claims, characterized in that one or more sensors, preferably one or more conductivity measuring cells (L1, L3) are arranged in the first circuit and are arranged upstream and downstream of the primary side (21) of the filter (20); and / or characterized in that one or more sensors, preferably one or more conductivity measuring cells (L2, L4) are arranged in the second circuit in the line (K) and / or in the filtrate line (F).

10. Apparatus in accordance with any one of the preceding claims, characterized in that one or more pressure measuring devices (S1, S2) are arranged downstream of the secondary side (22) of the filter (20) and / or upstream of the primary side (21) of the filter (20).

11. Apparatus in accordance with any one of the preceding claims, characterized in that the apparatus comprises an ultrafiltrate pump for removing dialysis solution, preferably from the return line (40) from the dialyzer (100) to the container (10) and / or comprises a balancing chamber (B) for the balanced supply and removal of dialysis solution to and from the dialyzer (100).

12. Apparatus in accordance with any one of the preceding claims, characterized in that the filter (20) is impermeable to gas; and / or in that the second circuit does not have a degassing device.

13. Apparatus in accordance with any one of the preceding claims, characterized in that the first and / or second circuits are closed or open.

14. Apparatus in accordance with any one of the preceding claims, characterized in that the container (10) is configured as a rigid vessel or as a bag, in particular as a flexible bag, further in particular as a single-use (disposable) article; and / or characterized in that the apparatus forms a dialysis machine or a part of a dialysis machine.

15. Method of preparing a dialysis solution using an apparatus in accordance with any one of the claims 1 to 14, characterized in that the solution is supplied from the container (10) to the primary side (21) of the filter (20) and the retentate is returned into the container (10), wherein a dialysis solution or a dialysis concentrate is supplied to the secondary side (22) of the filter (20) that is mixed with the permeate of the filter (20) on its secondary side (22).

16. Method in accordance with claim 15, characterized in that the permeate is supplied together with the dialysis solution or the dialyzate concentrate to a reservoir (200) in which a ready-to-use dialysis solution is prepared that is supplied to a dialyzer (100).

17. Method in accordance with claim 16, characterized in that the mixing region (200) is formed by the reservoir (200).

18. Method in accordance with any one of the claims 15 to 17, characterized in that the dialyzate concentrate contains only one single conductive component apart from water.

19. Method in accordance with any one of the claims 15 to 18, characterized in that a pump (51) is arranged in the line (K) and supplies a defined volume or a defined volume flow of dialysis solution or of dialyzate concentrate to the secondary side (22) of the filter (20).

20. Method in accordance with any one of the claims 15 to 19, characterized in that permeate arising on the secondary side (22) of the filter (20) is conducted together with the supplied dialysis solution or dialyzate concentrate into a balancing chamber (BK).

21. Method in accordance with any one of the claims 15 to 20, characterized in that permeate generated on the secondary side (22) of the filter (20) is conducted together with the supplied dialysis solution or dialyzate concentrate into the reservoir (200) or into the mixing region (200).