Flushing method and application of high gradient magnetic separator

Abstract

The present invention relates to the field of high gradient magnetic separators, and discloses a flushing method and application of high gradient magnetic separators. The method comprises: (A) introducing raw materials containing magnetic particles into a high gradient magnetic separator for magnetic separation, and when the high gradient magnetic separator reaches magnetic particle adsorption saturation or the content of magnetic particles in the product exceeds the design specified value, stopping the raw material feeding and product discharging, so that the feed liquid remains in the separation chamber of the high gradient magnetic separator, and closing the magnetic field; (B) emptying the separation chamber, allowing the feed liquid to flow for the first time and be discharged from the lower part of the separation chamber, to obtain a first concentrated solution containing magnetic particles; (C) introducing a flushing liquid from the upper part of the empty separation chamber, first eluting the magnetic particles remaining in the separation chamber from top to bottom, and discharging from the lower part of the separation chamber, to obtain a second concentrated solution containing magnetic particles. High-efficiency flushing is achieved at low flushing intensity, the process is simple, and the amount of flushing liquid used is small.

Description

Technical Field

[0001] The invention relates to the application field of a high gradient magnetic separator, and in particular to a flushing method and application of a high gradient magnetic separator. Background Art

[0002] High gradient magnetic separation technology emerged in the late 1960s. It uses electric or permanent magnets to generate a background magnetic field and can generate 10 5 The high magnetic field gradient of the order of T / m is suitable for capturing fine weak magnetic particles and is mainly used in mineral processing, non-metallic mineral purification, wastewater treatment and other fields. According to intermittent feeding or continuous feeding, it can be divided into periodic or continuous high-gradient magnetic separators. The working process of the periodic high-gradient magnetic separator is periodic. It is necessary to first turn on the excitation current to generate a magnetic field, and then feed into the separation chamber. The magnetic particles are adsorbed on the surface of the magnetic medium. When the adsorption is saturated or reaches the design value, the feeding is stopped, and then the current is cut off, the magnetic field is disconnected, and the medium pile is flushed to flush the magnetic particles. This process is called a separation and flushing cycle. The continuous high-gradient magnetic separator achieves continuous operation by alternately moving the medium pile. When the adsorption-saturated medium pile reaches the magnetic field-free area, it can be flushed for reuse.

[0003] At present, the flushing method of high gradient magnetic separator basically adopts liquid or gas for forward flushing or back flushing. After the combination of the above methods and multiple flushing, better results can be achieved. Water and air are commonly used flushing materials, but in the actual flushing operation, special equipment such as air compressors, gas tanks, flushing water pumps and flushing water tanks are required, which increases equipment investment and operating costs. In addition, if water is used, since the flushing effect is proportional to the flow rate of the flushing liquid, a large amount of flushing water needs to be consumed to obtain a good flushing effect, which leads to the generation of a large amount of wastewater and causes environmental pollution.

[0004] "Spiral Coil High Gradient Magnetic Separation Water Treatment" (Xie Shengyuan, Changchun Water Supply and Drainage Design Institute) discloses that when the retained material of the high gradient magnetic separator reaches saturation or the design specified value, backwashing is required to restore it to the original working state, and proposes to use a larger flushing intensity. Although backwashing with a small flow rate prolongs the flushing time, the flushing effect is not ideal.

[0005] CN1187274C discloses a method for treating secondary contaminated drinking water by high gradient magnetic separation, wherein the backwashing process of high gradient magnetic separation is: firstly, air backwashing is performed, the air compressor is turned on, and air backwashing is performed for 2 minutes (0.7MPa, flushing intensity 200L / (m 2 ·s)), then open the air compressor and the valve connected to the backwash water inlet pipe at the same time, and perform air and water flushing for 5 minutes (0.5MPa, air flushing intensity 200L / (m 2 ·s), water flushing intensity 100L / (m2 ·s)), and finally turn off the air compressor and flush with water for 3 minutes (0.5MPa, flushing intensity 100L / (m 2 ·s)). This flushing method has a long flushing time, large water consumption, large equipment investment and high operating costs.

[0006] CN105381875A discloses a non-disassembly and washing pulp high-gradient magnetic separator and a four-stage direct flushing forward and reverse cleaning method thereof, wherein the cleaning method comprises: the first stage of cleaning, using high-pressure water backwashing; the second stage of cleaning, using high-pressure water forward flushing; the third stage of cleaning, using high-pressure water backwashing; the fourth stage of cleaning, using high-pressure gas backwashing. This flushing method also has the problems of long flushing time, large water consumption, complex process, large equipment investment, and high operating cost.

[0007] In summary, it is urgent to develop a new flushing method for high gradient magnetic separators to solve the above problems. Summary of the invention

[0008] The purpose of the present invention is to overcome the problems of large amount of flushing liquid, multiple flushing equipment and complicated flushing process in the flushing process of the existing high gradient magnetic separator, and provide a flushing method and application of a high gradient magnetic separator.

[0009] In order to achieve the above object, the first aspect of the present invention provides a method for flushing a high gradient magnetic separator, comprising:

[0010] (A) introducing a raw material containing magnetic particles into a high gradient magnetic separator for magnetic separation, and when the high gradient magnetic separator reaches saturation of magnetic particle adsorption or the content of magnetic particles in the product exceeds a specified value, stopping the feeding of raw materials and discharging of products, so that liquid remains in the separation chamber of the high gradient magnetic separator, and turning off the magnetic field;

[0011] (B) emptying the separation chamber, allowing the feed liquid to flow by first gravity and be discharged from the lower part of the separation chamber to obtain a first concentrated solution containing magnetic particles;

[0012] (C) introducing a flushing liquid from the upper part of the emptied separation chamber, performing a first elution on the magnetic particles remaining in the separation chamber from top to bottom, and discharging the flushing liquid from the lower part of the separation chamber to obtain a second concentrated solution containing magnetic particles.

[0013] The second aspect of the present invention provides the use of the flushing method described in the first aspect in magnetic separation of a liquid raw material containing solid magnetic particles.

[0014] Through the above technical solution, the present invention has the following beneficial effects:

[0015] (1) utilizing the carrying and flushing effect of the liquid remaining in the high gradient magnetic separator to be flushed under gravity, and combining it with the separation effect produced by the elution of the flushing liquid under gravity, to achieve efficient flushing of the high gradient magnetic separator at a low flushing intensity;

[0016] (2) The process is relatively simple, the amount of flushing fluid used is small, and the flushing effect is good;

[0017] (3) Gravity is used as the flushing power, eliminating the need for special equipment such as air compressors, air storage tanks, and flushing water pumps, thus reducing equipment investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0019] Figure 1 It is a schematic diagram of a device for flushing a high gradient magnetic separator according to an embodiment of the present invention.

[0020] Description of Reference Numerals

[0021] 1-Raw material tank 2-High gradient magnetic separator 3-Product tank

[0022] 4- flushing liquid tank 5- concentrated liquid tank 101- separation feed valve

[0023] 102-separation discharge valve 103-vent valve 104-flushing feed valve

[0024] 105-Flush discharge valve DETAILED DESCRIPTION

[0025] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0026] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0027] A first aspect of the present invention provides a method for flushing a high gradient magnetic separator, comprising:

[0028] (A) introducing a raw material containing magnetic particles into a high gradient magnetic separator for magnetic separation, and when the high gradient magnetic separator reaches saturation of magnetic particle adsorption or the content of magnetic particles in the product exceeds a specified value, stopping the feeding of raw materials and discharging of products, so that liquid remains in the separation chamber of the high gradient magnetic separator, and turning off the magnetic field;

[0029] (B) emptying the separation chamber, allowing the feed liquid to flow by first gravity and be discharged from the lower part of the separation chamber to obtain a first concentrated solution containing magnetic particles;

[0030] (C) introducing a flushing liquid from the upper part of the emptied separation chamber, performing a first elution on the magnetic particles remaining in the separation chamber from top to bottom, and discharging the flushing liquid from the lower part of the separation chamber to obtain a second concentrated solution containing magnetic particles.

[0031] According to the present invention, the high gradient magnetic separator is a conventional device in the field of high gradient magnetic separation technology for magnetic separation of magnetic particles in wet or slurry materials, and its structure may include: a cylinder, a magnetic medium (such as magnetic stainless steel wool) filled in the cylinder, and a magnet (such as an electromagnet) surrounding the cylinder. The cylinder is provided with a magnetic medium, an internal component for fixing and supporting the magnetic medium, an upper / lower magnetic pole head for preventing magnetic leakage and making the magnetic field more uniform, and a separation chamber surrounded by the above components.

[0032] According to the present invention, the raw material can be a liquid phase fluid containing magnetic particles. The present invention has a relatively wide range of limitations on the raw material, for example, it can be a slurry containing magnetic particles in a non-metallic ore purification process, a wax liquid containing magnetic waste catalyst obtained by a Fischer-Tropsch synthesis reaction, wastewater or slurry containing magnetic particles produced by mineral processing, steelmaking and chemical industries, industrial sewage and urban sewage containing suspended matter (after adding magnetic particles, the suspended matter can be separated by a magnetic separation method), etc. Preferably, the average particle size of the magnetic particles in the raw material is ≤1000μm, and the content of the magnetic particles in the raw material is ≤10000mg / kg.

[0033] According to the present invention, in step (A), the raw material containing magnetic particles is introduced into the separation chamber of the high gradient magnetic separator for magnetic separation. Under the action of the magnetic field, the magnetic particles are adsorbed and deposited on the magnetic medium distributed in the separation chamber. As the magnetic separation proceeds, the magnetic particles adsorbed on the magnetic medium gradually accumulate. When the adsorption saturation state is reached or the content of magnetic particles in the product exceeds the specified value, the raw material feeding and product discharging are stopped, so that a certain amount of liquid remains in the separation chamber, and the magnetic field of the magnet is turned off to stop the magnetic separation. Through the above operation, the high gradient magnetic separator is switched from the separation operation state to the flushing state, waiting for flushing.

[0034] According to the present invention, in step (A), the feed liquid retained in the separation chamber is a mixture of raw materials that have not completed magnetic separation, fresh raw materials that have just entered the separation chamber, and products that have completed magnetic separation but have not been discharged in time. The amount of the feed liquid can be adjusted by controlling the sequence and time interval of the operation of stopping the raw material feeding and the product discharging. Preferably, the liquid level of the feed liquid is higher than the filling height of the magnetic medium in the separation chamber.

[0035] According to the present invention, in step (B), the first self-flow is carried out under the action of gravity, that is, the feed liquid is not subjected to a driving force other than gravity, and only flows downward by itself under the drive of gravity. Since the feed liquid has been immersed in the magnetic medium, it can contact the magnetic particles adsorbed by the magnetic medium in the separation chamber. In the process of downward self-flow, it can produce a carrying and flushing effect on a large number of magnetic particles, and discharge them together from the lower part of the separation chamber to obtain a first concentrated solution containing magnetic particles. Preferably, the flow rate of the first self-flow can be 0.5-10cm / s, and more preferably 1.5-8cm / s, so as to obtain a better magnetic particle carrying and flushing effect. The present invention does not limit the time of the first self-flow, starting from the time when the feed liquid begins to flow out from the lower part of the separation chamber driven by gravity until it is completely discharged.

[0036] According to the present invention, in step (C), the first elution is performed under the action of gravity, that is, the rinsing liquid is not subjected to a driving force other than gravity, and only moves downward from top to bottom under the driving force of gravity and leaches the magnetic particles retained in the separation chamber. Through the first elution, the magnetic particles retained in the separation chamber can be repeatedly switched between the state of entering the liquid phase environment from the gas phase environment, leaving the liquid phase environment, and then entering the gas phase environment. In this process, they are repeatedly subjected to the surface tension of the liquid, so that they can separate from the magnetic medium and be carried downward by the liquid; at the same time, the rinsing liquid carrying the magnetic particles and flowing downward can further increase the disturbance of the magnetic particles flowing through, making it easier for the magnetic particles to separate from the magnetic medium, thereby achieving a good rinsing effect.

[0037] In the present invention, by controlling the time of the first elution and the flow rate of the rinsing liquid, the amount of the rinsing liquid can be effectively controlled while obtaining a good rinsing effect. Preferably, the flow rate of the first elution can be 0.5-15 cm / s, more preferably 1.5-10 cm / s; the time of the first elution can be 5-120s, more preferably 10-30s.

[0038] According to the present invention, the method may further include: performing the following steps in sequence after step (C):

[0039] (D) introducing a flushing liquid from the upper part of the separation chamber and filling the separation chamber, and then emptying the separation chamber, so that the flushing liquid in the separation chamber undergoes a second gravity flow and is discharged from the lower part of the separation chamber to obtain a third concentrated solution containing magnetic particles;

[0040] (E) introducing a flushing liquid from the upper part of the emptied separation chamber, performing a second elution on the magnetic particles remaining in the separation chamber from top to bottom, and discharging the flushing liquid from the lower part of the separation chamber to obtain a fourth concentrated solution containing the magnetic particles;

[0041] Optionally, steps (D) and (E) are repeated.

[0042] According to the present invention, in step (D), by filling the separation chamber with the flushing liquid, the small amount of magnetic particles remaining in the separation chamber after step (C) can be more fully contacted with the flushing liquid, and continue to be carried and flushed during the second gravity flow of the flushing liquid, and discharged from the lower part of the separation chamber.

[0043] According to the present invention, in step (D), the second self-flow is carried out under the action of gravity, that is, the flushing liquid is not subjected to a driving force other than gravity, and only flows downward by itself under the drive of gravity. Preferably, the flow rate of the second self-flow can be 0.5-10 cm / s, and more preferably 1.5-8 cm / s. The present invention does not limit the time of the second self-flow, starting from when the feed liquid begins to flow out from the lower part of the separation chamber under the drive of gravity until it is completely discharged.

[0044] According to the present invention, in step (E), the second elution is performed under the action of gravity, that is, the rinsing liquid is not subjected to a driving force other than gravity, and only moves from top to bottom under the driving force of gravity and leaches the trace magnetic particles still remaining in the separation chamber to obtain a further rinsing effect. Preferably, the flow rate of the second elution can be 0.5-15 cm / s, more preferably 1.5-10 cm / s; the time of the second elution can be 5-120s, more preferably 10-30s.

[0045] According to the present invention, repeating steps (D) and (E) helps to obtain better flushing effect. From the perspective of balancing flushing efficiency, reducing the amount of flushing liquid and simplifying the operating process, preferably, step (D) and step (E) are performed 1-4 times, and more preferably 1-2 times.

[0046] According to one embodiment of the present invention, the flushing method of the high gradient magnetic separator can be implemented by the following device, such as Figure 1 As shown, the device may include:

[0047] Raw material tank 1, high gradient magnetic separator 2, product tank 3, flushing liquid tank 4, concentrated liquid tank 5, separation feed pipeline, separation discharge pipeline, venting pipeline, flushing feed pipeline and flushing discharge pipeline; wherein,

[0048] The separation feed pipeline is connected to the raw material tank 1 and the high gradient magnetic separator 2, and is used to introduce the raw material containing magnetic particles into the high gradient magnetic separator 2 for magnetic separation;

[0049] The separation discharge pipeline is connected to the high gradient magnetic separator 2 and the product tank 3, and is used to transport the product obtained after the magnetic separation to the product tank 3;

[0050] The flushing feed pipeline is connected to the flushing liquid tank 4 and the high gradient magnetic separator 2, and is used to introduce the flushing liquid from the upper part of the separation chamber of the high gradient magnetic separator 2, and to wash the magnetic particles retained in the separation chamber from top to bottom; the discharge port of the flushing liquid tank 4 is located higher than the flushing liquid feed port of the high gradient magnetic separator 2;

[0051] The flushing discharge pipeline is connected to the high gradient magnetic separator 2 and the concentrated liquid tank 5, and is used to transport the concentrated liquid containing magnetic particles obtained by flushing from the lower part of the separation chamber of the high gradient magnetic separator 2 to the concentrated liquid tank 5; the feed port of the concentrated liquid tank 5 is located lower than the flushing liquid discharge port of the high gradient magnetic separator 2;

[0052] The venting pipeline is connected to the flushing feed pipeline, and the air inlet position of the venting pipeline is higher than the flushing liquid tank 4.

[0053] The following combination Figure 1 The flushing method of the high gradient magnetic separator provided by the present invention is further described.

[0054] like Figure 1 As shown, the raw material containing magnetic particles (the average particle size of the magnetic particles is ≤1000 μm, and the content of the magnetic particles is ≤10000 mg / kg) is stored in the raw material tank 1, the high gradient magnetic separator 2 is energized to generate a magnetic field, the separation feed valve 101 on the separation feed pipeline and the separation discharge valve 102 on the separation discharge pipeline are opened, and the raw material containing magnetic particles is introduced into the high gradient magnetic separator 2 for magnetic separation, and the magnetic particles are adsorbed on the magnetic medium in the separation chamber, and the product obtained after separation enters the product tank 3; when the high gradient magnetic separation 2 reaches the saturation of magnetic particle adsorption, or the content of magnetic particles in the product exceeds the specified value of the design, the separation feed valve 101 and the separation discharge valve 102 are closed, the raw material feeding and product discharging are stopped, so that the separation chamber of the high gradient magnetic separation 2 has a feed liquid (the liquid level of the feed liquid is higher than the filling height of the magnetic medium in the separation chamber), and the magnetic field is turned off;

[0055] Open the vent valve 103 on the venting pipeline, then open the flushing discharge valve 105 on the flushing discharge pipeline to empty the separation chamber, so that the liquid in the separation chamber flows by first gravity (adjust the opening of the flushing discharge valve 105 to control the flow rate to 0.5-10 cm / s) and is discharged from the lower part of the separation chamber to obtain a first concentrated solution containing magnetic particles and send it to the concentrated solution tank 5;

[0056] Open the flushing feed valve 104, draw the flushing liquid from the flushing liquid tank 4, and introduce it from the upper part of the emptied separation chamber, perform the first elution on the magnetic particles retained in the separation chamber from top to bottom (adjust the opening of the flushing feed valve 104 to control the flow rate to 0.5-15 cm / s, and the elution time to 5-120 s), and discharge it from the lower part of the separation chamber to obtain a second concentrated solution containing magnetic particles and send it to the concentrated solution tank 5;

[0057] Then, optionally, perform the following steps in sequence:

[0058] Close the flushing discharge valve 105, introduce the flushing liquid from the upper part of the separation chamber and fill the separation chamber, then close the flushing feed valve 104, and then open the flushing discharge valve 105 to empty the separation chamber, so that the flushing liquid in the separation chamber flows by a second gravity flow (adjust the opening of the flushing discharge valve 105 to control the flow rate to 0.5-10 cm / s) and is discharged from the lower part of the separation chamber to obtain a third concentrated solution containing magnetic particles and send it to the concentrated solution tank 5;

[0059] Open the flushing feed valve 104, introduce the flushing liquid from the upper part of the emptied separation chamber, perform a second elution on the magnetic particles remaining in the separation chamber from top to bottom (adjust the opening of the flushing feed valve 104 to control the flow rate to 0.5-15 cm / s, and the elution time to 5-120 s), and discharge it from the lower part of the separation chamber to obtain a fourth concentrated solution containing magnetic particles and send it to the concentrated solution tank 5;

[0060] The above optional steps may be performed 1-4 times;

[0061] Close the flushing feed valve 104, flushing discharge valve 105 and vent valve 103, and the flushing process is completed.

[0062] The present invention will be described in detail below by way of examples. In the following examples and comparative examples,

[0063] High gradient magnetic separator: The separation chamber has a diameter of 100 mm and a height of 120 mm, and is filled with 2.5% by volume of magnetically conductive stainless steel wool (material: SUS430, diameter: 0.1 mm);

[0064] Raw materials: wastewater containing iron-based magnetic particles (magnetic particle content is 400 mg / kg), the average particle size of the magnetic particles is 14 μm, and the specific saturation magnetization is 55 emu / g;

[0065] Flushing liquid: fresh water;

[0066] Magnetic separation process conditions: The magnetic induction intensity generated by the magnet of the high gradient magnetic separator in the magnetic medium is 3000 Gauss, the cross-sectional flow rate of the raw material flowing through the high gradient magnetic separator is 7 mm / s, the magnetic separation time is 1 h, the single processing volume is 770 L, the magnetic separation efficiency is 95%, and the content of magnetic particles in the product is 20 mg / kg.

[0067] Example 1

[0068] use Figure 1 For the device shown, flush it as follows:

[0069] (A) The raw material is stored in a raw material tank 1, and the high gradient magnetic separator 2 is powered to generate a magnetic field. The separation feed valve 101 and the separation discharge valve 102 are opened, and the raw material is introduced into the high gradient magnetic separator 2 for magnetic separation. The magnetic particles are adsorbed on the magnetic medium in the separation chamber, and the product obtained after separation enters the product tank 3; when the high gradient magnetic separator 2 reaches the saturation of magnetic particle adsorption, the separation feed valve 101 and the separation discharge valve 102 are closed, and the raw material feeding and product discharging are stopped, so that there is feed liquid in the separation chamber of the high gradient magnetic separator 2, and the liquid level of the feed liquid is higher than the filling height of the magnetic medium in the separation chamber, and the magnetic field is closed;

[0070] (B) opening the drain valve 103, and then opening the flushing discharge valve 105 to empty the separation chamber, so that the liquid retained in the separation chamber in step (A) flows by first gravity and is discharged from the lower part of the separation chamber, thereby obtaining a first concentrated solution containing magnetic particles and sending it to the concentrated solution tank 5;

[0071] (C) opening the flushing feed valve 104, introducing the flushing liquid from the upper part of the separation chamber emptied in step (B), performing a first elution on the magnetic particles remaining in the separation chamber from top to bottom, and discharging the flushing liquid from the lower part of the separation chamber to obtain a second concentrated solution containing magnetic particles and feeding it to the concentrated solution tank 5;

[0072] (D) closing the flushing discharge valve 105, introducing the flushing liquid from the upper part of the separation chamber and filling the separation chamber, then closing the flushing feed valve 104, and then opening the flushing discharge valve 105 to empty the separation chamber, so that the flushing liquid in the separation chamber flows for a second time and is discharged from the lower part of the separation chamber, to obtain a third concentrated solution containing magnetic particles and send it to the concentrated solution tank 5;

[0073] (E) opening the flushing feed valve 104, introducing the flushing liquid from the upper part of the separation chamber emptied in step (D), performing a second elution on the magnetic particles remaining in the separation chamber from top to bottom, and discharging the flushing liquid from the lower part of the separation chamber to obtain a fourth concentrated solution containing magnetic particles and feeding it to the concentrated solution tank 5;

[0074] Close the flushing feed valve 104, flushing discharge valve 105 and vent valve 103, and the flushing process is completed.

[0075] The process parameters and flushing efficiency results of the flushing process are shown in Table 1.

[0076] Embodiment 2-6

[0077] The method of Example 1 is the same as that of Example 1, except that different process parameters are used in the rinsing process and the number of times of step (D) and step (E) are adjusted. Other conditions and operation process are the same as those of Example 1.

[0078] The process parameters and flushing efficiency results of the flushing process are shown in Table 1.

[0079] Comparative Example 1

[0080] Referring to the backwashing process of Example 1 in CN1187274C, a gas and liquid mixed backwashing method is adopted, wherein the air pressure is 0.5MPa, the flushing gas flow rate is 20cm / s, the flushing water pressure is 0.5MPa, the flushing water flow rate is 15cm / s, the single flushing time is 1min, and the flushing is 2 times. After calculation, the flushing efficiency is 98%, and the amount of flushing liquid is 141.37L.

[0081] Table 1

[0082]

[0083] It can be seen from Table 1 that the flushing method of the high gradient magnetic separator provided by the present invention has a small total flushing liquid consumption, high flushing efficiency and a simple process. However, Comparative Example 1 uses a conventional flushing method. Under the condition of obtaining the same or similar flushing efficiency, the total flushing liquid consumption of Comparative Example 1 is much higher than that of Examples 1-6.

[0084] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for flushing a high gradient magnetic separator, characterized in that: include: (A) introducing a raw material containing magnetic particles into a high gradient magnetic separator for magnetic separation, and when the high gradient magnetic separator reaches saturation of magnetic particle adsorption or the content of magnetic particles in the product exceeds a specified value, stopping the feeding of raw materials and discharging of products, so that liquid remains in the separation chamber of the high gradient magnetic separator, and turning off the magnetic field; (B) emptying the separation chamber, allowing the feed liquid to flow by first gravity and be discharged from the lower part of the separation chamber to obtain a first concentrated solution containing magnetic particles; (C) introducing a flushing liquid from the upper part of the emptied separation chamber, performing a first elution on the magnetic particles remaining in the separation chamber from top to bottom, and discharging the flushing liquid from the lower part of the separation chamber to obtain a second concentrated solution containing magnetic particles.

2. The method according to claim 1, wherein: The first gravity flow and the first elution are each independently performed under the action of gravity.

3. The method according to claim 1 or 2, wherein: In step (A), the raw material is a liquid phase fluid containing magnetic particles, and the average particle size of the magnetic particles is ≤1000 μm.

4. The method according to claim 3, wherein: In step (A), the content of magnetic particles in the raw material is ≤10000 mg / kg.

5. The method according to claim 3, wherein: In step (A), the liquid level of the remaining liquid in the separation chamber is higher than the filling height of the magnetic medium in the separation chamber.

6. The method according to claim 1 or 2, wherein: In step (B), the flow rate of the first gravity flow is 0.5-10 cm / s.

7. The method according to claim 6, wherein: In step (B), the flow rate of the first gravity flow is 1.5-8 cm / s.

8. The method according to claim 1 or 2, wherein: In step (C), the flow rate of the first elution is 0.5-15 cm / s; And / or, the first elution time is 5-120s.

9. The method according to claim 8, wherein: In step (C), the flow rate of the first elution is 1.5-10 cm / s; And / or, the first elution time is 10-30s.

10. The method according to any one of claims 1-2, 4-5, 7, and 9, wherein: The method further comprises: after step (C), performing the following steps in sequence: (D) introducing a flushing liquid from the upper part of the separation chamber and filling the separation chamber, and then emptying the separation chamber, so that the flushing liquid in the separation chamber undergoes a second gravity flow and is discharged from the lower part of the separation chamber to obtain a third concentrated solution containing magnetic particles; (E) introducing a flushing liquid from the upper part of the emptied separation chamber, performing a second elution on the magnetic particles remaining in the separation chamber from top to bottom, and discharging the flushing liquid from the lower part of the separation chamber to obtain a fourth concentrated solution containing the magnetic particles; Optionally, steps (D) and (E) are repeated.

11. The method according to claim 3, wherein: The method further comprises: after step (C), performing the following steps in sequence: (D) introducing a flushing liquid from the upper part of the separation chamber and filling the separation chamber, and then emptying the separation chamber, so that the flushing liquid in the separation chamber undergoes a second gravity flow and is discharged from the lower part of the separation chamber to obtain a third concentrated solution containing magnetic particles; (E) introducing a flushing liquid from the upper part of the emptied separation chamber, performing a second elution on the magnetic particles remaining in the separation chamber from top to bottom, and discharging the flushing liquid from the lower part of the separation chamber to obtain a fourth concentrated solution containing the magnetic particles; Optionally, steps (D) and (E) are repeated.

12. The method according to claim 6, wherein: The method further comprises: after step (C), performing the following steps in sequence: (D) introducing a flushing liquid from the upper part of the separation chamber and filling the separation chamber, and then emptying the separation chamber, so that the flushing liquid in the separation chamber undergoes a second gravity flow and is discharged from the lower part of the separation chamber to obtain a third concentrated solution containing magnetic particles; (E) introducing a flushing liquid from the upper part of the emptied separation chamber, performing a second elution on the magnetic particles remaining in the separation chamber from top to bottom, and discharging the flushing liquid from the lower part of the separation chamber to obtain a fourth concentrated solution containing the magnetic particles; Optionally, steps (D) and (E) are repeated.

13. The method according to claim 8, wherein: The method further comprises: after step (C), performing the following steps in sequence: (D) introducing a flushing liquid from the upper part of the separation chamber and filling the separation chamber, and then emptying the separation chamber, so that the flushing liquid in the separation chamber undergoes a second gravity flow and is discharged from the lower part of the separation chamber to obtain a third concentrated solution containing magnetic particles; (E) introducing a flushing liquid from the upper part of the emptied separation chamber, performing a second elution on the magnetic particles remaining in the separation chamber from top to bottom, and discharging the flushing liquid from the lower part of the separation chamber to obtain a fourth concentrated solution containing the magnetic particles; Optionally, steps (D) and (E) are repeated.

14. The method according to claim 10, wherein: The second gravity flow and the second elution are each independently performed under the action of gravity.

15. The method according to any one of claims 11 to 13, wherein: The second gravity flow and the second elution are each independently performed under the action of gravity.

16. The method according to claim 10, wherein: The flow rate of the second gravity flow is 0.5-10 cm / s; And / or, the flow rate of the second elution is 0.5-15 cm / s; And / or, the second elution time is 5-120s.

17. The method according to claim 16, wherein: The flow rate of the second gravity flow is 1.5-8 cm / s; And / or, the flow rate of the second elution is 1.5-10 cm / s; And / or, the second elution time is 10-30s.

18. The method according to any one of claims 11 to 14, wherein: The flow rate of the second gravity flow is 0.5-10 cm / s; And / or, the flow rate of the second elution is 0.5-15 cm / s; And / or, the second elution time is 5-120s.

19. The method according to claim 18, wherein: The flow rate of the second gravity flow is 1.5-8 cm / s; And / or, the flow rate of the second elution is 1.5-10 cm / s; And / or, the second elution time is 10-30s.

20. The method according to claim 15, wherein: The flow rate of the second gravity flow is 0.5-10 cm / s; And / or, the flow rate of the second elution is 0.5-15 cm / s; And / or, the second elution time is 5-120s.

21. The method according to claim 20, wherein: The flow rate of the second gravity flow is 1.5-8 cm / s; And / or, the flow rate of the second elution is 1.5-10 cm / s; And / or, the second elution time is 10-30s.

22. The method according to claim 10, wherein: The steps (D) and (E) are performed 1 to 4 times.

23. The method according to claim 22, wherein: The steps (D) and (E) are performed 1-2 times.

24. The method according to claim 15, wherein: The steps (D) and (E) are performed 1 to 4 times.

25. The method according to claim 24, wherein: The steps (D) and (E) are performed 1-2 times.

26. The method of claim 18, wherein: The steps (D) and (E) are performed 1 to 4 times.

27. The method according to claim 26, wherein: The steps (D) and (E) are performed 1-2 times.

28. The method according to any one of claims 11-14, 16-17, 19-21, wherein: The steps (D) and (E) are performed 1 to 4 times.

29. The method according to claim 28, wherein: The steps (D) and (E) are performed 1-2 times.

30. Use of the flushing method according to any one of claims 1 to 29 in magnetic separation of a liquid raw material containing solid magnetic particles.

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