A disc tube reverse osmosis device and its operation method

Abstract

The present invention discloses a disc tube reverse osmosis device and its operation method, which includes a raw water feed pump (1), a reverse osmosis membrane unit (2), a raw water circulation pump (3) and a one-way conduction control switch (4); the inlet end of the raw water feed pump (1) is communicated with the raw water outlet end, the outlet end of the raw water feed pump (1) is communicated with the inlet end of the raw water circulation pump (3), the outlet end of the raw water circulation pump (3) is communicated with the water inlet of the reverse osmosis membrane unit (2), the water production port of the reverse osmosis membrane unit (2) is communicated with the water production collection end, the concentrated water port of the reverse osmosis membrane unit (2) is respectively communicated with the conduction end of the one-way conduction control switch (4) and the concentrated water collection end, and the cut-off end of the one-way conduction control switch (4) is communicated with the connection branch of the raw water feed pump (1) and the raw water circulation pump (3). The cleaning of the device can be completed by means of direct flushing.

Description

Technical Field

[0001] The present invention relates to an operation method of a disk tube reverse osmosis device. Background Art

[0002] A common application form of microfiltration technology in water treatment is to make tubular membrane elements, which are internally composed of a certain number of tubular membrane cores combined according to specific rules. It generally has a cylindrical pressure vessel as the housing, and the ends are fixedly connected to the pressure vessel.

[0003] The disk tube reverse osmosis device uses the above-mentioned microfiltration technology. There are two defects in the existing disk tube reverse osmosis device. One is that it cannot be directly flushed; the other is that there are defects in its operation method. In the startup link, if a rapid startup is selected, the pressure difference inside the tubular membrane core will be too large, impacting and damaging the membrane sheets of the tubular membrane core. Instead, it needs to be started gradually, and the exhaust condition of the tubular membrane core needs to be observed manually while starting, which affects the startup rate. To sum up, how to balance the startup operation rate and avoid damaging the membrane sheets of the tubular membrane core is a technical problem that has not been solved by the existing disk tube reverse osmosis device. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a disk tube reverse osmosis device that can complete the cleaning of the device by direct flushing.

[0005] To solve the above technical problem, the technical solution provided by the present invention is as follows:

[0006] A disk tube reverse osmosis device includes a raw water feed pump, a reverse osmosis membrane unit, a raw water circulation pump, and a one-way conduction control switch; the inlet end of the raw water feed pump is communicated with the raw water outlet end, the outlet end of the raw water feed pump is communicated with the inlet end of the raw water circulation pump, the outlet end of the raw water circulation pump is communicated with the water inlet of the reverse osmosis membrane unit, the water production port of the reverse osmosis membrane unit is communicated with the water production collection end, the concentrated water port of the reverse osmosis membrane unit is respectively communicated with the conduction end of the one-way conduction control switch and the concentrated water collection end, and the cut-off end of the one-way conduction control switch is communicated with the connection branch of the raw water feed pump and the raw water circulation pump.

[0007] Further, it also includes a first flow rate control switch and a second flow rate control switch; the first flow rate control switch and the second flow rate control switch are arranged in parallel and one end is connected to the connection point of the concentrated water port of the reverse osmosis membrane unit and the conduction end of the one-way conduction control switch, and the other end is communicated with the concentrated water collection end.

[0008] Further, the one-way conduction control switch is one of a check valve, a one-way conduction valve, or a one-way regulating valve.

[0009] Further, the first flow rate control switch is an electric ball valve; the second flow rate control switch is an electric control valve.

[0010] Further, the reverse osmosis membrane unit is divided into multiple reverse osmosis membrane groups. The outlet end of the raw water circulation pump is respectively connected to the inlet of each reverse osmosis membrane group, and the concentrated water outlets of each reverse osmosis membrane group are combined into a branch and connected to the conducting end of the one-way conduction control switch.

[0011] Further, the raw water circulation pump is a variable frequency pump whose water inlet rate is adjustable according to its frequency.

[0012] Adopting the above structural design, compared with the prior art, it has the following advantages:

[0013] By configuring in the following manner, the concentrated water outlets of the reverse osmosis membrane unit are respectively connected to the conducting end and the concentrated water collection end of the one-way conduction control switch, and the cut-off end of the one-way conduction control switch is connected to the connection branch of the raw water feed pump and the raw water circulation pump. When flushing the entire device, only the one-way conduction control switch needs to be closed, and the direct flushing method can be adopted for flushing, which improves the flushing efficiency and flushing effect.

[0014] The technical problem to be solved by the present invention is to provide an operation method for a disk tube reverse osmosis device, taking into account the startup rate and preventing damage to the membrane sheets of the reverse osmosis membrane unit.

[0015] An operation method for a disk tube reverse osmosis device

[0016] Step 1: The raw water feed pump, the raw water circulation pump, the one-way conduction control switch, the first flow rate control switch, and the second flow rate control switch are closed;

[0017] Step 2: If the liquid levels of the raw water tank, the concentrated water tank, and the product water tank are greater than or equal to the set liquid levels of the disk tube reverse osmosis device, the raw water feed pump, the reverse osmosis membrane unit, the raw water circulation pump, the one-way conduction control switch, the first flow rate control switch, and the second flow rate control switch enter the standby state; otherwise, wait for the liquid level of the raw water tank.

[0018] Step 3: The raw water feed pump, the first flow rate control switch, and the second flow rate control switch are turned on.

[0019] Step 4: After the raw water feed pump runs for T1 time, the raw water circulation pump starts the low-frequency operation mode.

[0020] Step 5: The original water circulation pump operates in the low-frequency working mode for T2 time. If the number of air bubbles in the pipeline between the outlet end of the original water circulation pump and the inlet of the reverse osmosis membrane unit is greater than the set air bubble quantity value M1, the original water circulation pump continues to operate for T3 time; if the number of air bubbles is less than or equal to the set air bubble quantity value M1 of the equipment, the original water circulation pump gradually increases the frequency to the rated frequency and operates for T4 time;

[0021] Step 6: The first flow rate control switch is closed, and the second flow rate control switch is intermittently opened and closed until the water volume in the pipeline between the water production port of the reverse osmosis membrane unit and the water production collection end meets the set value W1 of the equipment;

[0022] Step 7: The disc tube reverse osmosis equipment enters the startup link.

[0023] Further, after the water volume in the pipeline between the water production port of the reverse osmosis membrane unit and the water production collection end meets the set value W1 of the equipment, the second flow rate control switch opens the small flow path mode.

[0024] Further, an air bubble sensor is installed in the pipeline between the outlet end of the original water circulation pump and the inlet of the reverse osmosis membrane unit, and the air bubble sensor is connected to the frequency conversion control end of the original water circulation pump.

[0025] Further, T1 is not greater than 5 minutes, T2 + T3 is not greater than 10 minutes, and T2 + T4 is not greater than 10 minutes.

[0026] Adopting the above operation method design, compared with the prior art, it has the following advantages:

[0027] By controlling the frequency of the original water circulation pump, the flow rate of the original water circulation pump can be controlled, and the number of air bubbles in the pipeline between the outlet end of the original water circulation pump and the inlet of the reverse osmosis membrane unit is monitored. It starts in a step-by-step manner to prevent a large pressure difference from being caused to the membrane sheets of the reverse osmosis membrane unit due to the rapid startup of the original water circulation pump. Secondly, by monitoring the number of air bubbles in the pipeline between the outlet end of the original water circulation pump and the inlet of the reverse osmosis membrane unit, the frequency of the original water circulation pump is increased, and the flow rate of the original water circulation pump is increased, taking into account the startup rate of the entire equipment. Description of the Drawings

[0028] Figure 1 It is a schematic diagram of the present invention.

[0029] As shown in the figure: 1. Raw water feed pump; 2. Reverse osmosis membrane unit; 3. Original water circulation pump; 4. One-way conduction control switch; 5. First flow rate control switch; 6. Second flow rate control switch; 7. Air bubble sensor. Detailed Embodiment

[0030] The present invention will be further described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0031] Embodiment 1

[0032] The present invention provides a disk tube reverse osmosis device, as shown in Figure 1 shown.

[0033] Its structure includes a raw water feed pump 1, a reverse osmosis membrane unit 2, a raw water circulation pump 3 and a one-way conduction control switch 4; the inlet end of the raw water feed pump 1 is communicated with the raw water outlet end, the outlet end of the raw water feed pump 1 is communicated with the inlet end of the raw water circulation pump 3, the outlet end of the raw water circulation pump 3 is communicated with the water inlet of the reverse osmosis membrane unit 2, the water production port of the reverse osmosis membrane unit 2 is communicated with the water production collection end, the concentrated water port of the reverse osmosis membrane unit 2 is respectively communicated with the conduction end of the one-way conduction control switch 4 and the concentrated water collection end, and the cut-off end of the one-way conduction control switch 4 is communicated with the connection branch of the raw water feed pump 1 and the raw water circulation pump 3.

[0034] In specific implementation, as a further solution, the disk tube reverse osmosis device further includes a first flow rate control switch 5 and a second flow rate control switch 6; the first flow rate control switch 5 and the second flow rate control switch 6 are arranged in parallel and one end is connected to the connection point of the concentrated water port of the reverse osmosis membrane unit 2 and the conduction end of the one-way conduction control switch 4, and the other end is communicated with the concentrated water collection end. The purpose of the above design is to control the flow rate and velocity, as well as the on-off control, to serve the start-up stage and the equipment cleaning stage of the device, bringing beneficial effects.

[0035] In specific implementation, as a further solution, the one-way conduction control switch 4 is one of a check valve, a one-way conduction valve or a one-way regulating valve, the first flow rate control switch 5 is an electric ball valve; the second flow rate control switch 6 is an electric regulating valve, and the raw water circulation pump 3 is a variable frequency pump whose water inlet rate is adjustable according to its frequency. The purpose of the above design is that the adjustment process is convenient and the adjustment range is controllable.

[0036] Further, the reverse osmosis membrane unit 2 is divided into multiple sections of reverse osmosis membrane groups, the outlet end of the raw water circulation pump 3 is respectively communicated with the water inlets of each reverse osmosis membrane group, and the concentrated water ports of each reverse osmosis membrane group are combined into a branch and communicated with the conduction end of the one-way conduction control switch 4. The purpose of the above design is to improve the processing capacity of the entire device.

[0037] The present invention provides an operation method of a disk tube reverse osmosis device, taking into account the start-up rate and preventing damage to the membrane sheets of the reverse osmosis membrane unit 2.

[0038] An operation method of a disk tube reverse osmosis device

[0039] Step 1: The raw water feed pump 1, the raw water circulation pump 3, the one-way conduction control switch 4, the first flow rate control switch 5, and the second flow rate control switch 6 are closed;

[0040] Step 2: If the liquid levels of the raw water tank, the concentrated water tank, and the product water tank are greater than or equal to the set liquid levels of the disc tube reverse osmosis equipment, the raw water feed pump 1, the reverse osmosis membrane unit 2, the raw water circulation pump 3, the one-way conduction control switch 4, the first flow rate control switch 5, and the second flow rate control switch 6 enter the standby state; otherwise, wait for the liquid level of the raw water tank;

[0041] Step 3: The raw water feed pump 1, the first flow rate control switch 5, and the second flow rate control switch 6 are turned on.

[0042] Step 4: After the raw water feed pump 1 operates for T1 time, the raw water circulation pump 3 starts the low-frequency operation mode.

[0043] Step 5: During the low-frequency operation mode of the raw water circulation pump 3 for T2 time, if the number of bubbles in the pipeline between the outlet end of the raw water circulation pump 3 and the inlet of the reverse osmosis membrane unit 2 is greater than the set bubble number value M1, the raw water circulation pump 3 continues to operate for T3 time; if the number of bubbles is less than or equal to the set bubble number value M1 of the equipment, the raw water circulation pump 3 gradually increases the frequency to the rated frequency and operates for T4 time.

[0044] Step 6: The first flow rate control switch 5 is closed, and the second flow rate control switch 6 is intermittently opened and closed until the water volume in the pipeline between the product water outlet of the reverse osmosis membrane unit 2 and the product water collection end meets the set value W1 of the equipment.

[0045] Step 7: The disc tube reverse osmosis equipment enters the startup phase.

[0046] By controlling the frequency of the raw water circulation pump 3, the flow rate of the raw water circulation pump 3 is made controllable, and the number of bubbles in the pipeline between the outlet end of the raw water circulation pump 3 and the inlet of the reverse osmosis membrane unit 2 is monitored. It is started in a step-by-step manner to prevent a large pressure difference from being caused to the membrane sheets of the reverse osmosis membrane unit 2 due to the rapid startup of the raw water circulation pump 3. Secondly, by monitoring the number of bubbles in the pipeline between the outlet end of the raw water circulation pump 3 and the inlet of the reverse osmosis membrane unit 2, the frequency of the raw water circulation pump 3 is increased, and the flow rate of the raw water circulation pump 3 is increased, taking into account the startup rate of the entire equipment.

[0047] In specific implementation, as a further solution, after the water volume in the pipeline between the water production outlet of the reverse osmosis membrane unit 2 and the water production collection end meets the set value W1 of the equipment, the second flow rate control switch 6 turns on the small flow path mode. The purpose of the above design is to reduce the pressure difference in the pipeline where the second flow rate control switch 6 is located and ensure the safety of the pipeline where the second flow rate control switch 6 is located.

[0048] In specific implementation, as a further solution, an air bubble sensor 7 is installed in the pipeline between the outlet end of the raw water circulation pump 3 and the inlet of the reverse osmosis membrane unit 2, and the air bubble sensor 7 is connected to the frequency conversion control end of the raw water circulation pump 3. The purpose of the above design is to accurately obtain the number of air bubbles in the pipeline between the outlet end of the raw water circulation pump 3 and the inlet of the reverse osmosis membrane unit 2. Among them, the air bubble sensor 7 is a sensor whose resistance changes with the number of air bubbles. By obtaining the resistance value of the sensor, the number of air bubbles can be obtained.

[0049] In specific implementation, as a further solution, T1 is not greater than 5 minutes, T2 + T3 is not greater than 10 minutes, and T2 + T4 is not greater than 10 minutes. The purpose of the above design is that the time setting meets the operating conditions and rates.

[0050] The above only explains the best embodiments of the present invention, but it should not be construed as a limitation on the claims. The present invention is not limited to the above embodiments, and all changes made within the protection scope of the independent claims of the present invention are within the protection scope of the present invention.

Claims

1. A method for operating a disk tube reverse osmosis device, characterized in that: The disk tube reverse osmosis device includes a raw water feed pump (1), a reverse osmosis membrane unit (2), a raw water circulation pump (3) and a one-way conduction control switch (4); the inlet end of the raw water feed pump (1) is connected to the raw water outlet end, the outlet end of the raw water feed pump (1) is connected to the inlet end of the raw water circulation pump (3), the outlet end of the raw water circulation pump (3) is connected to the water inlet of the reverse osmosis membrane unit (2), the water production port of the reverse osmosis membrane unit (2) is connected to the water production collection end, the concentrated water port of the reverse osmosis membrane unit (2) is respectively connected to the conduction end of the one-way conduction control switch (4) and the concentrated water collection end, and the cut-off end of the one-way conduction control switch (4) is connected to the connection branch of the raw water feed pump (1) and the raw water circulation pump (3); The disk tube reverse osmosis device further includes a first flow rate control switch (5) and a second flow rate control switch (6); The first flow rate control switch (5) and the second flow rate control switch (6) are arranged in parallel and one end is connected to the connection point between the concentrated water port of the reverse osmosis membrane unit (2) and the conduction end of the one-way conduction control switch (4), and the other end is connected to the concentrated water collection end; Step 1: The raw water feed pump (1), the raw water circulation pump (3), the one-way conduction control switch (4), the first flow rate control switch (5) and the second flow rate control switch (6) are closed; Step 2: If the liquid levels of the raw water tank, the concentrated water tank and the water production tank are greater than or equal to the set liquid levels of the disk tube reverse osmosis device, the raw water feed pump (1), the reverse osmosis membrane unit (2), the raw water circulation pump (3), the one-way conduction control switch (4), the first flow rate control switch (5) and the second flow rate control switch (6) enter the standby state; otherwise, wait for the liquid level of the raw water tank; Step 3: The raw water feed pump (1), the first flow rate control switch (5) and the second flow rate control switch (6) are opened, Step 4: After the raw water feed pump (1) operates for T1 time, the raw water circulation pump (3) starts the low-frequency operation mode; Step 5: The low-frequency operation mode of the raw water circulation pump (3) operates for T2 time. If the number of bubbles in the pipeline between the outlet end of the raw water circulation pump (3) and the water inlet of the reverse osmosis membrane unit (2) is greater than the set bubble number value M1, the raw water circulation pump (3) continues to operate for T3 time; if the number of bubbles is less than or equal to the set bubble number value M1 of the device, the raw water circulation pump (3) gradually increases the frequency to the rated frequency and operates for T4 time; Step 6: The first flow rate control switch (5) is closed, and the second flow rate control switch (6) is intermittently opened and closed until the water volume in the pipeline between the water production port of the reverse osmosis membrane unit (2) and the water production collection end meets the set value W1 of the device; Step 7: The disk tube reverse osmosis device enters the startup link.

2. The method for operating a disk tube reverse osmosis device according to claim 1, characterized in that: After the water volume in the pipeline between the water production port of the reverse osmosis membrane unit (2) and the water production collection end meets the set value W1 of the device, the second flow rate control switch (6) opens the small flow path mode.

3. A method for operating a disk tube reverse osmosis device according to claim 1, characterized in that: a bubble sensor (7) is installed in the pipeline between the outlet end of the raw water circulation pump (3) and the inlet of the reverse osmosis membrane unit (2), and the bubble sensor (7) is connected to the frequency conversion control end of the raw water circulation pump (3).

4. A method for operating a disk tube reverse osmosis device according to claim 1, characterized in that: T1 is not greater than 5 minutes, T2 + T3 is not greater than 10 minutes, and T2 + T4 is not greater than 10 minutes.

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