Chlorine measurement / filter testing / brine tank monitoring of a water treatment plant

Abstract

Pre-filtration unit of a water treatment plant, comprising a water line (6a) into which a dechlorination device (19) is connected, and with at least one chlorine sensor device (29, 30), characterized in that the dechlorination device (19) is connected to the at least one chlorine sensor device (29, 30) via lines (19a, 6b) and switching valves (31, 33) to check whether chlorine is present in the liquid flowing through the water line and to check the function of the dechlorination device (19), and in that a brine preparation device (16) is arranged, which is connected to the at least one chlorine sensor device (29, 30) via a further line (16a, 24a) into which an electrolysis cell (18) and subsequently a pump (23) and a release valve (28) are connected to supply electrolytically produced chlorine of known concentration to the at least one chlorine sensor device (29, 30) and to check its function.and that at least one chlorine sensor device (29, 30) has a free drain, wherein the chlorine sensor device (29, 30) has an online measuring total chlorine sensor.

Description

[0001] The invention relates to a fluid system for quality, function monitoring and / or control of physically and chemically acting filter stages of a water pretreatment for the operation of a reverse osmosis or other water treatment or water monitoring system.

[0002] A disadvantage of filter systems is the difficulty or impossibility of remotely diagnosing chlorine and hardness or monitoring the degree of contamination of mechanical filters.

[0003] Furthermore, for safety reasons, especially in dialysis water treatment, it is necessary to carry out extensive manual documentation of the water hardness and / or chlorine content daily, particularly to prove that the toxic chlorine has been removed from the liquid by the filters used.

[0004] Existing chlorine sensors for online measurement are often not regularly chlorinated or cannot provide reliable measurement results in the absence of chlorine in the liquid.

[0005] Water softeners are frequently used to remove salts that are difficult to dissolve, such as calcium and / or magnesium, from the water.

[0006] When using water softeners with acidic cation exchange resins, these must be regenerated regularly using sodium chloride brine solution.

[0007] This regeneration is usually carried out with sodium chloride solution, which is provided in a so-called brine tank in which salt is dissolved in a predetermined amount of liquid.

[0008] A failure of the regeneration process, e.g. due to a lack of sodium chloride brine solution, can lead to serious limescale buildup in the downstream systems.

[0009] Furthermore, due to the relatively large resin volumes, water softeners tend to be susceptible to microbial growth, leading to contamination of the liquid flowing through them.

[0010] Filter blockages are problematic because the resulting replacement of filter material usually involves an interruption of operation.

[0011] From EP2583950A1 an exemplary conventional method and a conventional arrangement for water treatment control are known.

[0012] The aim of the invention is to develop an actuator, sensor control and software that enables the user to evaluate the functionality of a system via online access and, on this basis, to obtain a remote diagnosis of the current operating status.

[0013] The present invention is defined in the independent claims. The dependent claims define advantageous embodiments of the invention.

[0014] To meet regulatory and / or internal requirements, the necessary documentation can be provided simultaneously via the connected IT system during automatic registration.

[0015] The targeted plant-specific evaluation through analysis and visualization of the operating parameters makes it possible to achieve an acyclic distribution of service deployments and thus a reduction in the number of services.

[0016] On this basis, a more economical and ecological approach is possible, as the deployment of trained personnel on site can be better coordinated and wear-related failures can be specifically and preventively avoided.

[0017] To avoid the aforementioned disadvantages, or rather to meet the objective, according to one aspect of the invention, partial flows are directed to the corresponding sensor before and after the filter stages via switched valves and evaluated by electronic measuring devices. These measuring devices can also be an integral part of downstream water treatment systems and / or a control room. Bidirectional operation for influencing actuators and sensors is possible.

[0018] Advantageously, different mechanical filter stages are monitored online for their degree of contamination using an electronic pressure sensor by measuring the pressures and determining the pressure difference, and with suitable filters equipped with corresponding backwashing automation, an automatic backwashing program is also initiated.

[0019] According to another aspect of the invention, an online measuring chlorine sensor is used, the safety-relevant function of which is checked according to the invention by regularly supplying electrolytically generated chlorine to the sensor at a known concentration.

[0020] The measurement result is electronically recorded and documented.

[0021] The chlorine can be produced from an existing brine solution.

[0022] The function of the water softener, i.e. the filtration and reduction of the poorly soluble calcium and magnesium salts, can be monitored by an ion-sensitive calcium and / or magnesium sensor.

[0023] The fill level of the brine tank, or the remaining volume of salts in the brine tank, can be easily monitored using a scale. For this purpose, the brine tank is placed on a support structure with a weighing cell. Since the support structure can be used regardless of the brine tank type, it is always advantageous to equip brine tanks already in operation with this monitoring device.

[0024] It is possible to display the brine volume directly or as a traffic light system with message color; forwarding and registration to a control center or a subsequent water treatment system, which may be designed as an RO system, is also possible.

[0025] This eliminates the need for daily inspection and documentation of the salt supply in the brine tank by operating personnel.

[0026] Regular, light chlorination of the water softener during regeneration, using electrolytically generated chlorine from the softener's brine tank, reduces microbial growth in the softener resin and thus ensures a germ-free liquid.

[0027] Fig. Figure 1 shows a pre-filtration unit according to the invention with a mechanical-chemical filter stage (4), an actuator-sensor monitoring unit (3), an associated evaluation electronics (2) and possible electronics (5) belonging, for example, to a subsequent reverse osmosis, wherein the electronics (2) can also be designed as control room electronics and communicates with electronics (5).

[0028] The mechanical-chemical filter stage (4) is shown only as an example with regard to the selection of the arranged filter stages in order to illustrate the function of the monitoring according to the invention.

[0029] The exemplary arrangement begins with the water inlet (6), a shut-off valve (8), and an automatically backwashable pre-filter (9) with a drain valve and drainage connection. This is followed by a safety shut-off valve (10), which is activated by a leak detector (22a) with a liquid sensor (22b).

[0030] Other components may include a pipe separator (11) and a backflow preventer (12) to prevent contamination of the water inlet (6).

[0031] At low water inlet pressures, a pressure booster unit (13) can be added. A further filter stage (14) can be designed as a cartridge filter (14a), a sand filter (14b), or as a hollow fiber filter in the nano- or ultraporous range (not shown here). (15) shows a water softener, for example, a double water softener, which is usually filled with highly acidic, cation-containing resin. When exhausted, this resin must be regularly regenerated with NaCl solution from the brine preparation (16). It is important to monitor the salt level in the brine tank (16). This is done with a weighing device (17), which is designed as a separate, structural base.

[0032] According to Fig. 2. The weighing device (17) consists of a weighing cell (46) whose signal can be amplified by electronics (44) on the weighing platform (42), electronically processed, or processed by electronics (2) as well as by any subsequent electronics (5). Preset weight limits of the brine tank can be monitored and displayed visually or audibly, or remotely diagnosed using computer processing.

[0033] The weighing cell (46) is attached to the weighing platform (42) by means of screws (48) such that one third of the brine or salt weight rests on the measuring base (47). The side stops (45) are attached to guide the brine container laterally.

[0034] By means of an electrolysis unit (18), a chlorine-containing solution can be formed from the brine flowing to the electrolysis cell (18) during the regeneration process of the water softener (15). It is understood that the chlorine concentration depends on the brine concentration, but essentially on the amount of electrical power supplied to the electrolysis cell. This significantly reduces microbial growth in the water softener resin.

[0035] (19) shows a double carbon filter / dechlorination unit used to filter the chlorine.

[0036] The filter stage (20) can act as a fine filter stage, removing the smallest particles from the filtered water (7) before it is fed, for example, to a reverse osmosis system or a drinking water system.

[0037] The actuator-sensor unit (3) can be equipped with an electronic water meter (21) for recording and reporting water consumption.

[0038] To monitor the chlorine content of the supplied liquid, a chlorine sensor (30) is preferably located in a chlorine sensor chamber (29), either for measuring total chlorine or free chlorine.

[0039] The chlorine sensor chamber (29) has an inlet and a free outlet. The release valve (28) is located directly in front of the sensor chamber.

[0040] The water supplier can usually chlorinate the supplied liquid with chlorine of varying concentrations, although depending on the hygiene conditions, there may be periods when no chlorine is introduced.

[0041] Therefore, in this case no statement can be made about the proper functioning of the sensor (30).

[0042] For regular testing of the chlorine sensor, the test valve (27), the brine suction valve (24), and the release valve (28) are opened, and the electrolysis cell (18) is switched on. Brine or chlorine-containing solution in a selected concentration ratio is drawn from the container (16) via the adjustable brine suction valve (24) and the pump (23), mixed with liquid via the flow restrictor (25), directed to the measuring chamber (29), registered by the chlorine sensor (30), and evaluated by the electronics (2) and (5).

[0043] This regular test ensures the proper functioning of the measuring cell (30).

[0044] The invention allows for the provision and monitoring of the sodium chloride brine solution solely for the purpose of chlorine sensor monitoring, independent of a water softener or other filter stages. In this context, the brine solution intake line and the electrolysis cell for electrolytic chlorine generation are routed independently of the brine intake line and the electrolysis cell of the water softener.

[0045] Pump (23) is shown as an example of a Venturi pump; other pump types are possible to achieve the function, in which case the chlorine-containing solution is added from line 24a to line 25a by means of a pump not shown.

[0046] To monitor the correct functioning of the carbon filter / dechlorination unit (19), a valve, for example (40) or (27), can first be opened. The release valve (28) is also opened. If chlorine is present in the supplied liquid, this is registered by the previously verified chlorine sensor (30).

[0047] The valves (33), (31), or (32) are then opened sequentially, as is the chlorine release valve (28). This allows the filter stages of the carbon filter to be tested. If the chlorine sensor registers the absence of chlorine, the filter test is successfully completed. It is in accordance with the invention that this measurement can also be performed independently and recorded electronically.

[0048] To monitor the filter stages (9), (14), (20), the pressure sensor (41) is selectively and successively connected to the pressures prevailing at the filter stages via the Fig. 1 valves arranged before or after the filter stages are actuated.

[0049] For example, the pressure drop of the filter stage (9) is monitored by measuring the inlet pressure via valve (37) and the outlet pressure is monitored by the valve (38).

[0050] Equivalent to the aforementioned measurement are in Fig. 1. To trace the measurement of the pressure drops by switching the valves (39 / 40) for the filter stages (14) and the valves (31 / 32) for filter stage (20).

[0051] The pressure drops at the softening (15) and dechlorination (19) can also be determined by successively switching the valves (40, 27, 33, 31).

[0052] Atmospheric relief of the pressure sensor (41) generally or between 2 measurements can be achieved via valve (34) as well as (28).

[0053] By measuring the flow through line 6 with a water meter / flow meter (21) or by a corresponding flow measurement in a subsequent treatment process, the pressure values ​​measured at the filters can be calculated to standard or average values ​​using electronics (2, 5) and a warning, replacement, flushing or maintenance time can be predicted for preset pressure differences.

[0054] Since the determination of filter pressure differences usually involves relative measurements, the use of a single pressure sensor (41) is advantageous both in terms of cost and calibration effort.

[0055] Normally, the water inlet pressures at line (6) e.g. at filter (9) are known, so that the pressure sensor (41) is subjected to a known pressure before the start of a measurement cycle to be verified as part of maintenance or technician inspection.

[0056] An advantageous embodiment of the pressure measurement is the determination of average pressure values ​​using electronics (2, 5) at the respective filters (9, 14, 15, 19, 20) by, for example, summing 50 measurements to obtain an average value and displaying it over an exemplary period of 1000 operating hours. Changes attributable to the end of the sensor's (41) service life or the clogging of the aforementioned filters can thus be detected or predicted electronically and queried remotely.

[0057] To monitor the correct function of the water softener (15), valve (40) is first opened and hard water is supplied to the calcium sensor (36) via the measuring chamber (35) through the open valve (34).

[0058] Subsequently, softened liquid is directed via flow restrictor (25), valves (27, 34) into the measuring chamber (35) to the ion-sensitive calcium sensor (36). legend 1. Pre-filtration with sensor package 2. Evaluation electronics (electronic sensor package) 3. Control unit (actuator and sensor unit) 4. Pre-filtration components 5. Electronics Post-filtration 6. Water inlet 7. Filtered water 8. Shut-off valve 9. Backwashable pre-filter with cleaning valve 10. Safety shut-off valve 11. Pipe separator 12. Backflow preventer 13. Pressure boosting unit 14. Fine filter stage 2 15th softening stage 16. Brine preparation plant and brine tank (brine preparation / brine tank) 17. Weighing unit 18. Electrolysis cell 19. Dechlorination unit (dechlorination stage / carbon filter) 20. Fine filter stage 3 21. Water meter / flow meter 22. Leakage detection with sensor 23. Pump (brine pump) 24. Brine intake valve 25. Adjustable throttle (flow throttle) 26. Backflow prevention 27. Chlorine sensor test valve / Calcium test valve 1 28. Release valve (chlorine sensor release valve) 29. Sensor chamber (chlorine sensor chamber) 30. Chlorine sensor 31. Switching valve (chlorine test valve II / fine filter stage 3 inlet pressure) 32. Chlorine test valve 111 / Fine filter stage 3 Outlet pressure 33. Chlorine test valve 1 34. Calcium sensor release valve 35. Calcium sensor chamber 36. Calcium sensor 37. Fine filter stage 1 Inlet pressure 38. Fine filter stage 1 Output pressure 39. Fine filter stage 2 Inlet pressure 40. Fine filter stage 2 Outlet pressure / Calcium test valve 41. Pressure sensor 6a Pipes Pipe (water pipe) 6b Management 16a Pipeline (Brine Pipeline) 19a Line 24a Line (Chlorine test line) 25a Pipeline (water pipe) 42. Platform 43. Adjustable feet 44. Electronics 45. Page boundary 46. ​​Weighing cell 47. Measuring foot 48. Mounting of the weighing cell

Claims

[1] Pre-filtration unit of a water treatment plant, comprising a water line (6a) into which a dechlorination device (19) is inserted, and comprising at least one chlorine sensor device (29, 30), characterized by, that the dechlorination device (19) is connected via lines (19a, 6b) and switching valves (31, 33) to the at least one chlorine sensor device (29, 30) in order to check whether chlorine is present in the liquid flowing through the water line and to check the function of the dechlorination device (19), that a brine preparation device (16) is arranged which is connected to the at least one chlorine sensor device (29, 30) via a further line (16a, 24a) in which an electrolysis cell (18) and then a pump (23) and a release valve (28) are connected in order to supply electrolytically produced chlorine of known concentration to the at least one chlorine sensor device (29, 30) and to check its function, and that the at least one chlorine sensor device (29, 30) has a free drain, wherein the chlorine sensor device (29, 30) has an online measuring total chlorine sensor. [2] Water treatment plant according to claim 1, furthermore characterized by a water softening device (15) to which the brine preparation device is connected via a brine line (16a), wherein the electrolysis cell (18) is connected in the brine line (16a), and a chlorine test line (24a) branches off from the brine line (16a) between the electrolysis cell (18) and the softening device (15), leading to the at least one chlorine sensor device (29, 30). [3] Water treatment plant according to claim 1, characterized by , that a water pipe (25a) also leads to the pump (23), into which an adjustable throttle (25) is inserted. [4] Water treatment plant according to claim 3, characterized by , that the pump (23) is a Venturi pump. [5] Water treatment plant according to claim 3 or 4, characterized by , that the chlorine-containing solution is added by means of a pump from line (24a) into line (25a). [6] Water treatment plant according to claims 1 to 5, characterized by that the chlorine sensor device has a sensor chamber (29) and a chlorine sensor (30). [7] Water treatment plant according to claim 6, characterized by , that the chlorine sensor (30) is connected to an evaluation electronics (2). [8] Water treatment plant according to claims 1 to 7, characterized by , that the release valve (28) is the last valve before the sensor chamber (29) is located and that the sensor chamber (29) has a drain. [9] Water treatment plant according to claims 1 to 8, characterized by , that the salt preparation plant has a brine tank (16) which is arranged on a weighing device (17). [10] Water treatment plant according to claims 1 to 9, characterized by , that the softening device (15) is a softener filled with strongly acidic cationic resin. [11] Water treatment plant according to claims 1 to 10, characterized by , that the size of the electrical power of the electrolysis cell (18) is adjustable by a control device (3). [12] Water treatment plant according to claims 1 to 11, characterized by , that a dechlorination device (19) is switched into the water line (6a), the outputs of which are connected via lines (19a, 6b) and the switching valves (31, 33) to the chlorine sensor device (29, 30). [13] Water treatment plant according to claims 1 to 12, characterized by that the water treatment plant is a reverse osmosis system. [14] Method for monitoring the function of a chlorine sensor device (29,30) of a pre-filtration unit of a water treatment plant, characterized by, that electrolytically generated chlorine of known concentration is supplied to the chlorine sensor device (29, 30) at time intervals and that the respective measured value of the chlorine sensor (30) is compared with an associated target value in order to check the function of the chlorine sensor device (29, 30), wherein the chlorine sensor device (29, 30) has an online measuring total chlorine sensor and the measurement result of the chlorine sensor device is preferably electronically recorded and documented by means of electronic data processing. [15] Method according to claim 14, characterized by , that the chlorine is produced from the salt solution of a brine container (16). [16] Method according to claim 15, characterized by , that the brine container (16) is connected to a softening device (15). [17] Method according to any one of claims 14 to 16, characterized by, that the chlorine is supplied to the chlorine sensor (30) during the regeneration process of the water softener (15). [18] Method according to any one of claims 14 to 17, characterized by , that the function of the water softening device (15) is monitored by an ion-sensitive calcium and / or magnesium sensor.

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