Cleaning method of novel silica sol concentration equipment

Abstract

The invention relates to the technical field of silica sol concentration equipment, and discloses a novel silica sol concentration equipment cleaning method, which comprises: starting an ultrafiltration membrane system, carrying out gas scrubbing on a membrane assembly, carrying out washing cleaning scrubbing on colloidal particles attached to the membrane surface, and after gas scrubbing is completed, carrying out washing cleaning on the colloidal particles, according to the method, the membrane assembly is subjected to gas scrubbing, the colloidal particles attached to the surface of the membrane are washed, cleaned and scrubbed, and then the colloidal particles blocking the membrane inlet holes are reversely flushed out of the membrane assembly by adopting backwashing operation, so that the performance recovery of the membrane is realized. The membrane assembly is subjected to gas scrubbing, the colloidal particles attached to the surface of the membrane are washed, cleaned and scrubbed, and the colloidal particles blocking the membrane inlet holes are reversely flushed out of the membrane assembly by adopting backwashing operation; the method comprises the following steps: recovering the performance of a membrane through a water inlet in the lower part of the membrane assembly to remove residual chemicals and air in the membrane assembly, and performing forward flushing on the membrane assembly because inlet water enters the membrane assembly from the water inlet in the lower part of the membrane assembly, flushes the outer surface of the membrane and is discharged from a concentrated water port in the top of the membrane assembly, thereby completing the effect of quickly cleaning the membrane.

Description

Technical Field

[0001] The invention relates to the technical field of silica sol concentration equipment, and more specifically, to a novel cleaning method for silica sol concentration equipment. Background Art

[0002] Silica sol is a colloidal solution, odorless and non-toxic. It has a low viscosity and can penetrate anywhere that water can penetrate, so it has very good dispersibility and permeability when mixed with other substances. Silica sol is often used as a binder for various refractory materials, and has the characteristics of strong adhesion and high temperature resistance. It is used in thin shell precision casting to make the shell mold strong and the casting smooth. Its modeling quality is better than that of water glass, and it can reduce costs and improve operating conditions by replacing ethyl silicate modeling. Silica sol has a high specific surface area and can be used in catalyst manufacturing and catalyst carriers, and in the coating industry. It can make the coating firm and has the functions of anti-fouling, dust-proof, aging-resistant, and fire-proof.

[0003] In the prior art, Chinese patent number "CN218281286U" discloses a silica sol membrane concentration device. This patented device aims to solve the problem that the concentration process of silica sol is often accompanied by particle clogging of the filter membrane, which leads to a gradual decrease in the concentration efficiency over time. By implanting an ultrasonic component in the ultrafiltration membrane assembly, ultrasonic and ultrafiltration can be achieved during the membrane concentration process, which can effectively reduce the clogging caused by the agglomeration of alternating silica particles and improve the concentration efficiency. This method mainly reduces the clogging of the ultrafiltration membrane. For the colloidal particles that have been blocked in the membrane pores, even if they are loosened by the action of the ultrasonic component, the colloid is pressed to one side of the membrane during the concentration process, so the loosened colloid can only continue to stay in the membrane pores. Summary of the invention

[0004] In order to solve the problems raised in the above background technology, the present invention provides a novel cleaning method for silica sol concentration equipment.

[0005] The present invention provides a novel cleaning method for silica sol concentration equipment, which adopts the following technical scheme: A novel cleaning method for silica sol concentration equipment comprises the following steps:

[0006] Step 1: Start the ultrafiltration membrane system, first perform air scrubbing on the membrane assembly to flush and clean the colloidal particles attached to the membrane surface, and return the washed water to the transfer water tank. After the air scrubbing is completed, the colloidal particles that block the membrane pores are reversely flushed out of the membrane assembly by backwashing to restore the membrane performance. The backwashing water also flows back to the transfer water tank;

[0007] Step 2: Then, the membrane module is positively flushed to remove the residual chemicals and air in the membrane module. Positive flushing is that water enters the membrane module from the water inlet at the bottom of the membrane module, flushes the outer surface of the membrane, and is discharged from the concentrated water outlet at the top of the membrane module;

[0008] Step 3. After the cleaning is completed, the system can be switched to the filtering operation state. After running for one cycle, it will change according to the water inlet conditions and the cleaning procedure. Pollutants will be intercepted during the filtration process, and the transmembrane pressure difference (TMP) will rise. At the end of the pre-set operation steps, it will enter the backwash cleaning step.

[0009] Preferably, before starting the ultrafiltration membrane system in step one, it is necessary to first start the water supply pump, fill the device with water and set the forward flushing frequency to once every 20 to 30 minutes, set and adjust the backwash pressure frequency to once every 20 to 30 minutes, set and adjust the air intake pressure to 200 kPa, and set the air washing frequency to once every 20 to 30 minutes.

[0010] Preferably, in step 1, the steps of air scrubbing the membrane assembly are as follows:

[0011] (1) Slowly open the air inlet valve and adjust it to the specified air inlet pressure of 200 kPa, and the air inlet volume of a single membrane module is: 5 Nm3 / hr;

[0012] (2) The air wash lasts for 60 seconds, during which the gas will produce an oscillation effect inside the membrane module to help remove pollutants on the membrane surface;

[0013] (3) After the air wash is completed, close the air inlet valve to stop the air supply.

[0014] Preferably, in step 2, the steps of positively flushing the membrane assembly are as follows:

[0015] (1) Turn on the UF water inlet pump and prepare to introduce water from the UF water inlet side;

[0016] (2) Control the amount of water entering the membrane module by adjusting the manual water inlet valve to ensure that the water flow is stable and not too large. Discharge the flushing water from the upper positive flushing discharge valve to ensure that the water flows smoothly through the membrane module and removes surface dirt;

[0017] (3) Each positive flushing time is 30 seconds, which flushes away the dirt formed on the outer surface of the membrane during the filtration process and also plays the role of water filling. The positive flushing flow rate is 6m 3 / hr, and each membrane module is above 45L. This flow rate should be as large as possible without affecting the structural integrity of the membrane module in order to more effectively remove pollutants.

[0018] Preferably, the backwashing step in step three is as follows:

[0019] (1) Set the backwash flow rate to 0.5 to 1.5 times the filtration flow rate, and the backwash flow rate is 6m 3 / hr, and each membrane module is more than 45L to avoid excessive pressure on the hollow fiber membrane, and keep the backwash water pressure below 300kPa to prevent excessive pressure from damaging the membrane fibers;

[0020] (2) Open the water production valve and flushing discharge valve, and start the backwash pump;

[0021] (3) Then continue flushing the water in the water production tank until the water coming out of the discharge port no longer contains foam to remove any protective liquid or other impurities that may be present.

[0022] Preferably, one cycle in step three is 0.5-1 hour, and in step two, the positive flushing time is 1-2 minutes.

[0023] In summary, the present invention includes the following beneficial technical effects:

[0024] The present invention performs air scrubbing on the membrane assembly to flush and clean the colloidal particles attached to the membrane surface, and then uses a backwashing operation to reversely flush the colloidal particles blocking the membrane inlet holes out of the membrane assembly to achieve recovery of membrane performance, and then performs positive flushing on the membrane assembly to remove residual chemicals and air in the membrane assembly. Positive flushing is due to the fact that water enters the membrane assembly from the water inlet at the bottom of the membrane assembly, flushes the outer surface of the membrane, and is discharged from the concentrated water outlet at the top of the membrane assembly, thereby completing the effect of quickly cleaning the membrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the process structure in an embodiment of the present invention. DETAILED DESCRIPTION

[0026] The following is combined with Figure 1 The present invention is described in further detail.

[0027] It should be noted that the drawings are schematic and not to scale. For the sake of clarity and convenience, the relative sizes and proportions of the parts shown in the drawings are exaggerated or reduced in size, and any size is only illustrative and not restrictive. In addition, the same reference symbol is used for the same structure, element or accessory appearing in more than two figures to reflect similar features.

[0028] The embodiment of the present invention discloses a novel cleaning method for silica sol concentration equipment. Figure 1 A novel cleaning method for silica sol concentration equipment comprises the following steps:

[0029] Step 1: Before starting the ultrafiltration membrane system, you need to start the water supply pump first, fill the device with water and set the forward flushing frequency to once every 20 to 30 minutes, set and adjust the backwash pressure to once every 20 to 30 minutes, set and adjust the air inlet pressure to 200 kPa, and set the air wash frequency to once every 20 to 30 minutes;

[0030] Then the ultrafiltration membrane system is used to air-clean the membrane components. The steps for air-cleaning the membrane components are as follows:

[0031] (1) Slowly open the air inlet valve and adjust it to the specified air inlet pressure of 200 kPa, and the air inlet volume of a single membrane module is: 5 Nm3 / hr;

[0032] (2) The air wash lasts for 60 seconds, during which the gas will produce an oscillation effect inside the membrane module to help remove pollutants on the membrane surface;

[0033] (3) After the air wash is completed, close the air inlet valve to stop the air supply;

[0034] The colloidal particles attached to the membrane surface are washed and scrubbed, and the washed water is returned to the transfer water tank. After the air scrubbing is completed, the colloidal particles blocking the membrane pores are reversely flushed out of the membrane assembly by backwashing to restore the membrane performance. The backwashing water is also returned to the transfer water tank;

[0035] Step 2: Then the steps for positive flushing of the membrane assembly are as follows:

[0036] (1) Turn on the UF water inlet pump and prepare to introduce water from the UF water inlet side;

[0037] (2) Control the amount of water entering the membrane module by adjusting the manual water inlet valve to ensure that the water flow is stable and not too large. Discharge the flushing water from the upper positive flushing discharge valve to ensure that the water flows smoothly through the membrane module and removes surface dirt;

[0038] (3) Each positive flushing time is 30 seconds, which flushes away the dirt formed on the outer surface of the membrane during the filtration process and also plays the role of water filling. The positive flushing flow rate is 6m 3 / hr, and each membrane module is more than 45L. This flow rate should be as large as possible without affecting the structural integrity of the membrane module to remove the residual chemicals and air in the membrane module. Positive flushing is when water enters the membrane module from the water inlet at the bottom of the membrane module, flushes the outer surface of the membrane, and is discharged from the concentrated water outlet at the top of the membrane module;

[0039] Step 3: After the cleaning is completed, the system can be switched to the filtering operation state. After running for a cycle of 0.5-1 hour, it changes according to the water inlet conditions and the cleaning procedure. During the filtration process, pollutants are intercepted and the transmembrane pressure difference (TMP) will rise. At the end of the pre-set operation steps, it will enter the backwashing step as follows:

[0040] (1) Set the backwash flow rate to 0.5 to 1.5 times the filtration flow rate, and the backwash flow rate is 6m 3 / hr, and each membrane module is more than 45L to avoid excessive pressure on the hollow fiber membrane, and keep the backwash water pressure below 300kPa to prevent excessive pressure from damaging the membrane fibers;

[0041] (2) Open the water production valve and flushing discharge valve, and start the backwash pump;

[0042] (3) Then continue flushing the water in the water production tank until the water coming out of the discharge port no longer contains foam to remove any protective liquid or other impurities that may be present;

[0043] Circulate in sequence to achieve the process of cleaning the membrane components;

[0044] Through the above structural design, the effect of rapid cleaning of the membrane is achieved.

[0045] Finally, a few points should be explained: First, in the description of the present invention, it should be noted that, unless otherwise specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, which may refer to mechanical connection or electrical connection, or internal communication between two components, or direct connection. "upper", "lower", "left", "right", etc. are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may change;

[0046] Secondly: In the drawings of the embodiments disclosed in the present invention, only the structures related to the embodiments disclosed in the present invention are involved, and other structures can refer to the general design. In the absence of conflict, the same embodiment and different embodiments of the present invention can be combined with each other;

[0047] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A novel cleaning method for silica sol concentration equipment, characterized in that: The steps include: Step 1: Start the ultrafiltration membrane system, first perform air scrubbing on the membrane assembly to flush and clean the colloidal particles attached to the membrane surface, and return the washed water to the transfer water tank. After the air scrubbing is completed, the colloidal particles that block the membrane pores are reversely flushed out of the membrane assembly by backwashing to restore the membrane performance. The backwashing water also flows back to the transfer water tank; Step 2: Then, the membrane module is positively flushed to remove the residual chemicals and air in the membrane module. Positive flushing is that water enters the membrane module from the water inlet at the bottom of the membrane module, flushes the outer surface of the membrane, and is discharged from the concentrated water outlet at the top of the membrane module; Step 3. After the cleaning is completed, the system can be switched to the filtering operation state. After running for one cycle, it will change according to the water inlet conditions and the cleaning procedure. Pollutants will be intercepted during the filtration process, and the transmembrane pressure difference (TMP) will rise. At the end of the pre-set operation steps, it will enter the backwash cleaning step.

2. The cleaning method of a novel silica sol concentration equipment according to claim 1 is characterized in that: Before starting the ultrafiltration membrane system in step one, it is necessary to first start the water supply pump, fill the device with water and set the forward flushing frequency to once every 20 to 30 minutes, set and adjust the backwash pressure frequency to once every 20 to 30 minutes, set and adjust the air inlet pressure to 200 kPa, and set the air washing frequency to once every 20 to 30 minutes.

3. The cleaning method of a novel silica sol concentration equipment according to claim 1 is characterized in that: In the step 1, the steps of air scrubbing the membrane assembly are as follows: (1) Slowly open the air inlet valve and adjust it to the specified air inlet pressure of 200 kPa, and the air inlet volume of a single membrane module is: 5 Nm3 / hr; (2) The air wash lasts for 60 seconds, during which the gas will produce an oscillation effect inside the membrane module to help remove pollutants on the membrane surface; (3) After the air wash is completed, close the air inlet valve to stop the air supply.

4. The cleaning method of a novel silica sol concentration device according to claim 1 is characterized in that: In step 2, the steps of positively flushing the membrane assembly are as follows: (1) Turn on the UF water inlet pump and prepare to introduce water from the UF water inlet side; (2) Control the amount of water entering the membrane module by adjusting the manual water inlet valve to ensure that the water flow is stable and not too large. Discharge the flushing water from the upper positive flushing discharge valve to ensure that the water flows smoothly through the membrane module and removes surface dirt; (3) Each positive flushing time is 30 seconds, which flushes away the dirt formed on the outer surface of the membrane during the filtration process and also plays the role of water filling. The positive flushing flow rate is 6m 3 / hr, and each membrane module is above 45L. This flow rate should be as large as possible without affecting the structural integrity of the membrane module in order to more effectively remove pollutants.

5. The cleaning method of a novel silica sol concentration equipment according to claim 1 is characterized in that: The backwashing steps in step three are as follows: (1) Set the backwash flow rate to 0.5 to 1.5 times the filtration flow rate, and the backwash flow rate is 6m 3 / hr, and each membrane module is more than 45L to avoid excessive pressure on the hollow fiber membrane, and keep the backwash water pressure below 300kPa to prevent excessive pressure from damaging the membrane fibers; (2) Open the water production valve and flushing discharge valve, and start the backwash pump; (3) Then continue flushing the water in the water production tank until the water coming out of the discharge port no longer contains foam to remove any protective liquid or other impurities that may be present.

6. The cleaning method of a novel silica sol concentration device according to claim 1 is characterized in that: One cycle in step three is 0.5-1 hour, and in step two, the positive flushing time is 1-2 minutes.

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