A pure water machine and a method for testing a desalination rate of an RO membrane to determine whether the membrane is damaged

Abstract

A water purifier includes a composite filter, an RO filter, and a post-filter. A booster pump, an inlet solenoid valve, and a raw water TDS sensor are installed on the pipeline between the outlet of the composite filter and the inlet of the RO filter. A pure water TDS sensor is installed on the pipeline between the RO filter and the post-filter. The water purifier also includes a detection and desalination rate calculation module and an alarm. The detection and desalination rate calculation module calculates the desalination rate based on the measured TDS values ​​of the raw water and pure water, and determines whether the RO membrane is damaged based on two consecutive desalination rate readings. This invention has a reasonable structure, a simple and accurate membrane rupture detection method, and can promptly detect the RO membrane to ensure drinking water safety.

Description

Technical Field

[0001] This invention belongs to the field of water treatment technology, and relates to a pure water machine, specifically a pure water machine and a method for testing the desalination rate of an RO membrane to determine whether the membrane is damaged. Background Technology

[0002] With increasingly severe water pollution, urban water safety has become a prominent issue. To address secondary pollution of tap water and the presence of harmful substances in tap water due to raw water contamination, water purifiers are increasingly being used. Currently, household water filtration primarily utilizes RO (reverse osmosis) water purifiers. These systems treat municipal tap water through a coarse filtration system and RO reverse osmosis filtration to produce potable water. The RO membrane is the core component for reverse osmosis; it is an artificial semi-permeable membrane with specific characteristics, mimicking biological semi-permeable membranes. It is generally made of polymer materials such as cellulose acetate membranes, aromatic polyhydrazine membranes, and aromatic polyamide membranes. RO membranes require cleaning or replacement after a period of use. Currently, the replacement interval for domestically produced RO membranes is approximately 1-2 years, but this can vary depending on water quality and water consumption in different regions. Damaged RO membranes must be replaced promptly. Current water purifiers do not have an automatic function to detect RO membrane damage and issue an alarm.

[0003] To judge the performance of an RO membrane, the following four aspects should be considered: water efficiency, flux, stability, and desalination rate. The desalination rate is an important indicator of an RO reverse osmosis water purifier. It mainly reflects the RO membrane's ability to filter ionic impurities in the water. It is generally tested with a TDS meter. A normal desalination rate is around 90%. If the desalination rate drops significantly, it indicates that the RO membrane is seriously fouled or damaged and needs to be cleaned and replaced as soon as possible. Summary of the Invention

[0004] The first technical problem to be solved by this invention is to provide a pure water machine with a reasonable structure that can accurately determine whether the RO membrane is damaged and provide an alarm in time.

[0005] The second technical problem to be solved by the present invention is to provide a method for testing the desalination rate of an RO membrane to determine whether the membrane is damaged.

[0006] The technical solution adopted by the present invention to solve the first technical problem mentioned above is as follows: a pure water machine, including a filtration system, a booster pump, an inlet solenoid valve, a controller, and a connector for connecting the above components. The filtration system includes a composite filter element, an RO filter element, and a post-filter element. The inlet of the composite filter element is connected to a tap water pipe, and the outlet of the post-filter element is connected to a faucet through an outlet pipe. The booster pump and the inlet solenoid valve are installed on a first pipe between the outlet of the composite filter element and the inlet of the RO filter element. The machine is characterized in that: a raw water TDS water quality sensor is installed on the first pipe, and a pure water TDS water quality sensor is installed on a second pipe between the RO filter element and the post-filter element. The pure water machine is also equipped with a detection and desalination rate calculation module and an alarm. The detection and desalination rate calculation module calculates the desalination rate by measuring the TDS values ​​of the raw water and pure water obtained by the raw water TDS water quality sensor and the pure water TDS water quality sensor, and judges whether the RO membrane is damaged based on the continuous two-time desalination rate.

[0007] Furthermore, the detection and desalination rate calculation module includes a raw water TDS water quality sensor, a pure water TDS water quality sensor, and a controller. The raw water TDS water quality sensor and the pure water TDS water quality sensor are respectively connected to their respective detection signal input terminals of the controller. Finally, one output signal terminal of the controller also needs to be connected to an alarm.

[0008] Furthermore, the continuous double desalination rate refers to the desalination rate measured twice being less than 70%.

[0009] Furthermore, the alarm uses an indicator light to alert the user that the RO membrane is damaged by flashing red lights.

[0010] Finally, a low-pressure switch is installed on the first pipeline, a check valve and a high-pressure switch are installed on the second pipeline, and a combined solenoid valve is installed on the concentrate outlet pipeline of the RO filter element.

[0011] The technical solution adopted by the present invention to solve the second technical problem mentioned above is: a method for determining whether the RO membrane is damaged by testing the desalination rate of any of the above-mentioned pure water machines, characterized by including the following steps:

[0012] 1) After the water purifier is powered on and has produced water for a cumulative period of 20 to 40 minutes, the booster pump will continuously produce water for 30 to 90 seconds. The detection and desalination rate calculation module will calculate the desalination rate by measuring the TDS values ​​of the raw water and pure water using the raw water TDS water quality sensor and the pure water TDS water quality sensor. If the desalination rate is higher than the preset value, the machine will work normally.

[0013] 2) If the calculated desalination rate is lower than the preset value, continue to produce water for another 30 to 90 seconds and calculate the desalination rate again. If the desalination rate is lower than the preset value in both cases, the membrane rupture alarm will be triggered and the machine will stop producing water; otherwise, it will work normally.

[0014] Preferably, step 1) requires that after accumulating 30 minutes of water production, the booster pump continuously produces water for 60 seconds; step 2) requires that the booster pump continuously produces water for 60 seconds.

[0015] Further preferred, if the single water production time in step 1) is less than 60 seconds, the TDS value is not updated and the desalination rate is not calculated.

[0016] Finally, the preset value is 70%.

[0017] Compared with existing technologies, the advantages of this invention are as follows: The RO membrane is damaged by testing its desalination rate. To ensure accuracy, two consecutive tests are performed. If both tests are below 70%, the membrane is considered damaged and needs immediate replacement. An alarm is also included for timely alerts. This invention's water purifier has a reasonable structure, a simple and accurate judgment method, and allows for timely detection and replacement of the RO membrane if damage is detected, ensuring safe drinking water. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the water circuit of the pure water machine according to an embodiment of the present invention;

[0019] Figure 2 This is a flowchart of the membrane rupture determination method according to an embodiment of the present invention. Detailed Implementation

[0020] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0021] like Figure 1 As shown, a pure water machine includes a filtration system, a booster pump 5, an inlet solenoid valve 6, control components, and connectors for connecting the above components. The filtration system includes a composite filter element 1, an RO filter element 2, and a post-filter element 3. The inlet of the composite filter element 1 is connected to a tap water pipe 10, and the outlet of the post-filter element 3 is connected to a water tap 11 via an outlet pipe. The booster pump 5 and the inlet solenoid valve 4 are installed on a first pipe between the outlet of the composite filter element 1 and the inlet of the RO filter element 2. A low-pressure switch 6 and a raw water TDS water quality sensor 12 are also installed on the first pipe. A pure water TDS water quality sensor 13, a check valve 8, and a high-pressure switch 7 are installed on a second pipe between the RO filter element 2 and the post-filter element 3. A combined solenoid valve 9 is provided on the concentrated water outlet pipe of the RO filter element 2. There is also a controller, which connects at least the raw water TDS water quality sensor 12 and the pure water TDS water quality sensor 13 to their respective detection signal input terminals to form part of the detection module, while the controller's output signal terminals are respectively connected to the inlet solenoid valve 4, the booster pump 5, and the combination solenoid valve 9.

[0022] The water purifier also includes a detection and desalination rate calculation module and an alarm. The detection and desalination rate calculation module includes a raw water TDS water quality sensor 12, a pure water TDS water quality sensor 13, and a controller. The raw water TDS water quality sensor 12 and the pure water TDS water quality sensor 13 are respectively connected to their respective detection signal input terminals of the controller, which is equivalent to including part of the aforementioned detection module. In addition, it also includes a calculation module, which has a module to calculate the desalination rate based on the parameters obtained from the detection. Finally, one output signal terminal of the controller also needs to be connected to the alarm.

[0023] The detection and desalination rate calculation module calculates the desalination rate by measuring the TDS values ​​of raw water and pure water using the raw water TDS water quality sensor 12 and the pure water TDS water quality sensor 13, and determines whether the RO membrane is damaged based on the continuous secondary desalination rate. The continuous secondary desalination rate refers to the desalination rate measured twice being less than 70%.

[0024] The formula for calculating the desalination rate is: Desalination rate = (TDS value of raw water - TDS value of pure water) / TDS value of raw water.

[0025] The methods for determining whether an RO membrane is damaged are as follows:

[0026] like Figure 2 As shown, a method for testing the desalination rate of an RO membrane to determine whether the membrane is damaged includes the following steps:

[0027] 1) After the water purifier is powered on and has produced water for a total of 30 minutes, the booster pump will continuously produce water for 60 seconds. The detection and desalination rate calculation module will calculate the desalination rate by measuring the TDS values ​​of the raw water and pure water through the raw water TDS water quality sensor 12 and the pure water TDS water quality sensor 13. If the desalination rate is higher than 70%, the machine will work normally.

[0028] 2) If the calculated desalination rate is less than 70%, continue water production for another 60 seconds and calculate the desalination rate again. If the desalination rate is less than 70% in both cases, a membrane rupture alarm will be triggered. The controller will cause the alarm light to flash red, and the machine will stop producing water. It will need to be powered on again to resume operation. Otherwise, it will work normally, which means that the membrane is not damaged and no alarm is required.

[0029] It should be noted that the TDS value will not be measured within 20 minutes of the water purifier being powered on (to avoid false alarms due to the new machine and new membrane). If the water production time is less than 60 seconds, the TDS value will not be updated and the desalination rate will not be calculated.

[0030] This example only illustrates the scenario of cumulative water production of 30 minutes and continuous water production by the booster pump for 60 seconds. Technicians can modify it to other suitable time periods for testing. The preset value for the secondary desalination rate is 70%, which can be adjusted appropriately by technicians depending on the model.

[0031] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A water purifier, comprising a filtration system, a booster pump, an inlet solenoid valve, a controller, and a connector for connecting the above components, wherein the filtration system includes a composite filter element, an RO filter element, and a post-filter element, the inlet of the composite filter element being connected to a tap water pipe, the outlet of the post-filter element being connected to a faucet via an outlet pipe, and the booster pump and the inlet solenoid valve being disposed on a first pipe between the outlet of the composite filter element and the inlet of the RO filter element, characterized in that: The first pipeline is equipped with a raw water TDS water quality sensor, and the second pipeline between the RO filter and the post-filter is equipped with a pure water TDS water quality sensor. The pure water machine is also equipped with a detection and desalination rate calculation module and an alarm. The detection and desalination rate calculation module is configured to: after the pure water machine has accumulated 20 to 40 minutes of water production, control the booster pump to continuously produce water for 30 to 90 seconds, and then calculate the desalination rate by measuring the TDS values ​​of the raw water and pure water through the raw water TDS water quality sensor and the pure water TDS water quality sensor, and determine whether the RO membrane is damaged based on whether the desalination rate measured twice in a row is lower than the preset value. The detection and desalination rate calculation module includes a raw water TDS water quality sensor, a pure water TDS water quality sensor, and a controller. The raw water TDS water quality sensor and the pure water TDS water quality sensor are respectively connected to their respective detection signal input terminals of the controller. Finally, one output signal terminal of the controller also needs to be connected to an alarm. The term "continuous double desalination rate" refers to a desalination rate measured twice that is both below 70%.

2. The pure water machine according to claim 1, characterized in that: The alarm uses an indicator light to alert the user that the RO membrane is damaged by flashing red light.

3. The pure water machine according to claim 1, characterized in that: The first pipeline is also equipped with a low-pressure switch, the second pipeline is equipped with a check valve and a high-pressure switch, and the concentrated water outlet pipeline of the RO filter element is equipped with a combined solenoid valve.

4. A method for determining whether a water purifier is damaged by testing the desalination rate of its RO membrane according to any one of claims 1 to 3, characterized in that... Includes the following steps: 1) After the water purifier is powered on and has produced water for a cumulative period of 20-40 minutes, the booster pump will continuously produce water for 30-90 seconds. The detection and desalination rate calculation module will calculate the desalination rate by measuring the TDS values ​​of the raw water and pure water using the raw water TDS water quality sensor and the pure water TDS water quality sensor. If the desalination rate is higher than the preset value, the machine will work normally. 2) If the calculated desalination rate is lower than the preset value, the booster pump will be controlled to continuously produce water for 30-90 seconds, and the desalination rate will be calculated again. If the desalination rate is lower than the preset value twice in a row, the membrane rupture alarm will be triggered and the machine will stop producing water; otherwise, it will work normally.

5. The method according to claim 4, characterized in that: Step 1) requires that after accumulating 30 minutes of water production, the booster pump continuously produces water for 60 seconds; Step 2) requires that the booster pump continuously produce water for 60 seconds.

6. The method according to claim 5, characterized in that: If the water production time for a single cycle is less than 60 seconds in step 1), the TDS value will not be updated and the desalination rate will not be calculated.

7. The method according to claim 4, characterized in that: The preset value is 70%.

Images