Flocculating agent for papermaking sewage treatment and preparation method thereof

Abstract

The invention belongs to the technical field of flocculating agents, and particularly relates to a flocculating agent for papermaking sewage treatment and a preparation method of the flocculating agent. Comprising the following components: 2-8 parts of cassava starch, 2-5 parts of polyvinyl alcohol, 15-18 parts of chitosan, 8-12 parts of polyaluminum chloride, 6-8 parts of potassium sulfate, 1-2 parts of polyacrylamide, 10-16 parts of kaolin and 15-18 parts of ammonium ferrous sulfate. The flocculant does not cause secondary pollution to sewage treatment, and is applicable to various types of sewage and wastewater due to high molecular weight, multiple functional groups in a molecular chain and high charge density, and meanwhile, the chitosan, the cassava starch and other resources are rich and low in price, and the production process is simple.

Description

Technical Field

[0001] The invention belongs to the technical field of flocculants, and in particular relates to a flocculant for papermaking wastewater treatment and a preparation method thereof. Background Art

[0002] Flocculants play an important role in the sewage treatment process. Inorganic flocculants (such as polyaluminium chloride, polyferric sulfate, etc.) are widely used because of their low price, easy availability, and high cationic charge density. However, their disadvantage is that when treating sewage, the flocs formed are small, and the flocs are slowly separated from the water. A small number of tiny particles can be suspended in the water for a long time, making it difficult to separate them from the water body. Organic polymer flocculants have been increasingly widely used due to their advantages such as small dosage of agents, small amount of flocs produced, and easy separation of flocs. However, traditional inorganic flocculants not only have large dosages and low effectiveness, but also cause secondary pollution. Summary of the invention

[0003] The purpose of the present invention is to provide a flocculant for papermaking wastewater treatment and a preparation method thereof in order to solve the above-mentioned technical problems, thereby achieving the effect of less pollution and low cost.

[0004] In view of this, the present invention provides a flocculant for papermaking wastewater treatment, comprising the following components: 2-8 parts of cassava starch, 2-5 parts of polyvinyl alcohol, 15-18 parts of chitosan, 8-12 parts of polyaluminium chloride, 6-8 parts of potassium sulfate, 1-2 parts of polyacrylamide, 10-16 parts of kaolin, and 15-18 parts of ammonium ferrous sulfate.

[0005] In this technical solution, the flocculant will not cause secondary pollution to sewage treatment. Due to its high molecular weight, many functional groups in the molecular chain, and high charge density, it can be applied to many types of sewage and wastewater. At the same time, chitosan, cassava starch and other resources are abundant, low-priced, and have a simple production process.

[0006] Furthermore, the flocculant and the preparation method thereof comprise the following steps:

[0007] S1. Weigh cassava starch, polyvinyl alcohol, chitosan, polyaluminium chloride, potassium sulfate, polyacrylamide, kaolin and ammonium ferrous sulfate for later use;

[0008] S2, crushing the kaolin, passing it through a 100-200 mesh sieve, and spheroidizing with graphite for 30 minutes to obtain kaolin powder;

[0009] S3, mixing polyaluminium chloride and chitosan solution, adjusting the pH value of the mixed solution to 4, stirring for 5-10 minutes, precipitating for 30 minutes, and drying and aging to obtain a solid powder;

[0010] S4, putting the solid powder in step S3, kaolin powder, tapioca starch, polyvinyl alcohol, potassium sulfate, polyacrylamide and ammonium ferrous sulfate into spheroidal graphite, and using wet spheroidal graphite for 1h-1.5h;

[0011] S5, taking out the mixture obtained after the spheroidal graphite in step S4, granulating, drying, crushing, and then sieving with a screening machine to obtain a flocculant.

[0012] Furthermore, the screening machine includes a base, a vibration motor is arranged in the base, a screening tank is connected to the base through a spring, the vibration motor is used to drive the screening tank to vibrate, the screening tank includes a feed port, at least two filter screens are arranged in sequence along the axial direction in the screening tank, the mesh diameter of the filter screen gradually decreases from top to bottom, and a discharge port is arranged corresponding to each filter screen on the screening tank.

[0013] In this technical solution, the dried product may have some agglomeration or uneven particle size, and needs to be crushed and screened to reach the specified particle size range. The particle size of the general product is between 20-80 mesh. The crushed and screened product can be packaged and sold and used as a finished product.

[0014] Furthermore, a material baffle plate is arranged above the first layer of filter screen. The material baffle plate is arc-shaped and coaxial with the screening tank, and a discharge channel is formed between the material baffle plate and the wall of the screening tank.

[0015] In this technical solution, the material is poured from the feed port onto the first layer of filter screen. Due to the vibration of the screening tank, the material will rotate in one direction and gradually move centrifugally outward and then be discharged from the discharge port. In order to prevent small particles from passing through the discharge port before being screened, a baffle plate is provided so that the material can only be discharged after moving in one direction through the discharge channel, thereby increasing the material's travel path and the time the material stays on the filter plate, ensuring that it is screened in place and improving the screening quality.

[0016] Furthermore, a rubber strip is provided below the baffle plate, and the rubber strip is in contact with the surface of the filter screen.

[0017] In the technical solution, the rubber strip is arranged so that it can be in flexible contact with the rubber strip during the vibration of the filter screen, thereby reducing damage to the filter screen.

[0018] Furthermore, a screen cleaning component is correspondingly arranged below the filter screen, and the screen cleaning component cleans the filter screen by knocking the filter screen.

[0019] Furthermore, the net cleaning component comprises:

[0020] A support plate, the support plate is arranged below the filter screen, a through hole is formed on the support plate, the through hole is larger than the aperture of the mesh of the filter screen, an annular connecting plate is extended toward the filter screen to be fixedly connected with the filter screen, and the support plate, the filter screen and the connecting plate are surrounded to form a receiving space;

[0021] A bouncing ball is arranged in the accommodating space, and the bouncing ball has elasticity and can bounce along with the vibration of the screening tank.

[0022] In the present technical solution, a bouncing ball is arranged so that it can bounce along with the vibration of the screening tank, and hit the filter screen during the bouncing process, so that the impurities deposited or stuck on the filter screen and in the mesh of the filter screen are shaken off, thereby preventing the filter screen from being blocked.

[0023] Furthermore, a plurality of limiting belts are arranged in the accommodating space. The limiting belts are made of PU material and are in a circular shape. At least two bouncing balls are arranged within the range of each limiting belt.

[0024] In this technical solution, the limiting belt can limit the lateral movement range of the bouncing ball, so that the bouncing ball focuses on vertical jumping. At the same time, the limiting belt can also jump in the accommodating space and hit the filter to achieve the purpose of cleaning the filter.

[0025] Furthermore, a needle-like puncture portion is provided on the upper surface of the limiting belt, and the diameter of the puncture portion is smaller than the mesh diameter of the filter screen.

[0026] In the technical solution, when the limiting belt jumps upward, the puncture part can be inserted into the mesh of the filter screen to push out the blockage stuck in the mesh, so as to facilitate further cleaning of the screen.

[0027] Furthermore, the screening machine has three layers of filters.

[0028] The beneficial effects of the present invention are:

[0029] 1. This flocculant will not cause secondary pollution to sewage treatment. Due to its high molecular weight, many functional groups in the molecular chain, and high charge density, it can be applied to many types of sewage and wastewater. At the same time, chitosan, cassava starch and other resources are abundant, low-priced, and have a simple production process.

[0030] 2. The material is poured from the feed port onto the first layer of filter screen. Due to the vibration of the screening tank, it will rotate in one direction and gradually move centrifugally outward and then be discharged from the discharge port. In order to prevent small particles from passing through the discharge port before screening, a baffle plate is set so that the material can only be discharged after moving in one direction through the discharge channel, which increases the material's travel path and the time the material stays on the filter plate, ensuring that it is screened in place and improving the screening quality.

[0031] 3. The rubber strip is provided so that the filter can be in flexible contact with the rubber strip during the vibration of the filter, thereby reducing damage to the filter.

[0032] 4. The bouncing ball can bounce along with the vibration of the screening tank, and will hit the filter screen during the bouncing process, so that the impurities deposited or stuck on the filter screen and in the mesh of the filter screen will be shaken off, thus preventing the filter screen from being blocked.

[0033] 5. The limiting belt can limit the lateral movement range of the bouncing ball, so that the bouncing ball focuses on vertical jumping. At the same time, the limiting belt can also jump in the accommodating space and hit the filter to achieve the purpose of cleaning the filter.

[0034] 6. When the limit belt jumps upward, the puncture part can be inserted into the mesh of the filter screen to push out the blockage stuck in the mesh, making it easier to clean the screen. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a stereogram of the present invention;

[0036] Figure 2 is a cross-sectional view of the screening tank;

[0037] Figure 3 This is a three-dimensional image of the first filter layer;

[0038] Figure 4 It is an exploded view of the screen cleaning assembly and the filter;

[0039] Figure 5 It is a three-dimensional picture of the screen cleaning assembly;

[0040] Figure 6 yes Figure 5 A partial enlarged view of the middle A;

[0041] The symbols in the figure are:

[0042] 1. Base; 2. Screening tank; 3. Feed inlet; 4. Filter screen; 5. Discharge port; 6. Baffle plate; 7. Discharge channel; 8. Rubber strip; 9. Screen cleaning assembly; 10. Support plate; 11. Through hole; 12. Connecting plate; 13. Bouncing ball; 14. Limiting belt; 15. Puncture part. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0044] In the description of the present application, it should be noted that the terms used herein are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. For ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0045] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0046] It should be noted that, in the description of the present application, the orientation or positional relationship indicated by terms such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise stated, these orientation words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present application; the orientation words "inside and outside" refer to the inside and outside relative to the contour of each component itself.

[0047] It should be noted that, in the present application, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises one..." does not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be noted that the scope of the method and device in the embodiment of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0048] Embodiment 1

[0049] A flocculant for treating papermaking wastewater comprises the following components: 2-8 parts of cassava starch, 2-5 parts of polyvinyl alcohol, 15-18 parts of chitosan, 8-12 parts of polyaluminium chloride, 6-8 parts of potassium sulfate, 1-2 parts of polyacrylamide, 10-16 parts of kaolin and 15-18 parts of ammonium ferrous sulfate.

[0050] This flocculant will not cause secondary pollution to sewage treatment. Due to its high molecular weight, many functional groups in the molecular chain and high charge density, it can be applied to many types of sewage and wastewater. At the same time, chitosan, cassava starch and other resources are abundant, low-priced and have a simple production process.

[0051] Embodiment 2

[0052] The flocculant and the preparation method thereof comprise the following steps:

[0053] S1. Weigh cassava starch, polyvinyl alcohol, chitosan, polyaluminium chloride, potassium sulfate, polyacrylamide, kaolin and ammonium ferrous sulfate for later use;

[0054] S2, crushing the kaolin, passing it through a 100-200 mesh sieve, and spheroidizing with graphite for 30 minutes to obtain kaolin powder;

[0055] S3, mixing polyaluminium chloride and chitosan solution, adjusting the pH value of the mixed solution to 4, stirring for 5-10 minutes, precipitating for 30 minutes, and drying and aging to obtain a solid powder;

[0056] S4, putting the solid powder in step S3, kaolin powder, tapioca starch, polyvinyl alcohol, potassium sulfate, polyacrylamide and ammonium ferrous sulfate into spheroidal graphite, and using wet spheroidal graphite for 1h-1.5h;

[0057] S5, taking out the mixture obtained after the spheroidal graphite in step S4, granulating, drying, crushing, and then sieving with a screening machine to obtain a flocculant.

[0058] Embodiment 3

[0059] like Figure 1-3 As shown, the screening machine includes a base 1, a vibration motor is arranged in the base 1, a screening tank 2 is connected to the base 1 through a spring, the vibration motor is used to drive the screening tank 2 to vibrate, the screening tank 2 includes a feed port 3, at least two filter screens 4 are arranged in sequence along the axial direction in the screening tank 2, and the screening machine has three layers of filter screens 4. The mesh aperture of the filter screen 4 gradually decreases from top to bottom, and a discharge port 5 is arranged on the screening tank 2 corresponding to each filter screen 4.

[0060] The dried product may have some lumps or uneven particle size, which requires crushing and screening to reach the specified particle size range. The particle size of the general product is between 20-80 mesh. The crushed and screened products can be packaged and sold and used as finished products.

[0061] A material baffle plate 6 is arranged above the first layer of filter screen 4 . The material baffle plate 6 is arc-shaped and coaxial with the screening tank 2 . A material discharge channel 7 is formed between the material baffle plate 6 and the tank wall of the screening tank 2 .

[0062] The material is poured from the feed port 3 onto the first layer of filter screen 4. Due to the vibration of the screening tank 2, the material will rotate in one direction and gradually move centrifugally outward and then be discharged from the discharge port 5. In order to prevent small particles from passing through the discharge port 5 before being screened, a baffle plate 6 is provided so that the material can only be discharged after moving in one direction through the discharge channel 7, thereby increasing the material's travel path and the time the material stays on the filter plate, ensuring that it is screened in place and improving the screening quality.

[0063] A rubber strip 8 is provided below the baffle plate 6, and the rubber strip 8 contacts the surface of the filter screen 4. The rubber strip 8 can be flexibly contacted with the rubber strip 8 during the vibration of the filter screen 4, which can reduce damage to the filter screen 4.

[0064] Embodiment 4

[0065] like Figure 4-6 As shown, a screen cleaning component 9 is correspondingly arranged below the filter screen 4 , and the screen cleaning component 9 cleans the filter screen by knocking the filter screen 4 .

[0066] The net cleaning component 9 comprises:

[0067] A support plate 10, the support plate 10 is arranged below the filter screen 4, a through hole 11 is opened on the support plate 10, the through hole 11 is larger than the aperture of the mesh hole of the filter screen 4, the support plate 10 extends toward the filter screen 4 to have an annular connecting plate 12 for fixed connection with the filter screen 4, and the support plate 10, the filter screen 4 and the connecting plate 12 enclose a receiving space;

[0068] The bouncing ball 13 is arranged in the accommodating space, and the bouncing ball 13 has elasticity and can bounce along with the vibration of the screening tank 2 .

[0069] The bouncing ball 13 can bounce along with the vibration of the screening tank 2, and hit the filter screen 4 during the bouncing process, so that the impurities deposited or stuck on the filter screen 4 and in the mesh of the filter screen 4 are shaken off, thereby preventing the filter screen 4 from being blocked.

[0070] A plurality of limiting belts 14 are arranged in the accommodation space. The limiting belts 14 are made of PU material and are in a circular shape. At least two bouncing balls 13 are arranged within the range of each limiting belt 14. The limiting belts 14 can limit the lateral movement range of the bouncing balls 13, so that the bouncing balls 13 focus on vertical jumping. At the same time, the limiting belts 14 can also jump in the accommodation space and can also hit the filter 4 to achieve the purpose of clearing the net. A puncture portion 15 in the shape of a needle is arranged on the upper surface of the limiting belt 14. The diameter of the puncture portion 15 is smaller than the mesh diameter of the filter 4. When the limiting belt 14 jumps upward, the puncture portion 15 can be inserted into the mesh of the filter 4 to push out the blockage stuck in the mesh, so as to facilitate further cleaning of the net.

[0071] The embodiments of the present application are described above in conjunction with the accompanying drawings. In the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A flocculant for papermaking wastewater treatment, characterized in that , including the following components: 2-8 parts of cassava starch, 2-5 parts of polyvinyl alcohol, 15-18 parts of chitosan, 8-12 parts of polyaluminium chloride, 6-8 parts of potassium sulfate, 1-2 parts of polyacrylamide, 10-16 parts of kaolin, and 15-18 parts of ammonium ferrous sulfate.

2. A method for preparing the flocculant according to claim 1, characterized in that: The following steps are involved: S1. Weigh cassava starch, polyvinyl alcohol, chitosan, polyaluminium chloride, potassium sulfate, polyacrylamide, kaolin and ammonium ferrous sulfate for later use; S2, crushing the kaolin, passing it through a 100-200 mesh sieve, and spheroidizing with graphite for 30 minutes to obtain kaolin powder; S3, mixing polyaluminium chloride and chitosan solution, adjusting the pH value of the mixed solution to 4, stirring for 5-10 minutes, precipitating for 30 minutes, and drying and aging to obtain a solid powder; S4, putting the solid powder in step S3, kaolin powder, tapioca starch, polyvinyl alcohol, potassium sulfate, polyacrylamide and ammonium ferrous sulfate into spheroidal graphite, and using wet spheroidal graphite for 1h-1.5h; S5, taking out the mixture obtained after the spheroidal graphite in step S4, granulating, drying, crushing, and then sieving with a screening machine to obtain a flocculant.

3. The method for preparing a flocculant according to claim 2, characterized in that: The screening machine comprises a base (1), a vibration motor is arranged in the base (1), a screening tank (2) is connected to the base (1) via a spring, the vibration motor is used to drive the screening tank (2) to vibrate, the screening tank (2) comprises a feed inlet (3), at least two filter screens (4) are arranged in sequence along the axial direction in the screening tank (2), the mesh diameters of the filter screens (4) gradually decrease from top to bottom, and a discharge port (5) is arranged on the screening tank (2) corresponding to each filter screen (4).

4. The method for preparing a flocculant according to claim 3, characterized in that: A material baffle plate (6) is arranged above the first layer of filter screen (4); the material baffle plate (6) is arc-shaped and coaxial with the screening tank (2); a material discharge channel (7) is formed between the material baffle plate (6) and the tank wall of the screening tank (2).

5. The method for preparing a flocculant according to claim 4, characterized in that: A rubber strip (8) is provided below the baffle plate (6), and the rubber strip (8) is in contact with the surface of the filter screen (4).

6. The method for preparing a flocculant according to claim 5, characterized in that: A screen cleaning component (9) is correspondingly arranged below the filter screen (4), and the screen cleaning component (9) cleans the filter screen by knocking the filter screen (4).

7. The method for preparing a flocculant according to claim 6, characterized in that: The net cleaning component (9) comprises: A support plate (10), the support plate (10) being arranged below the filter screen (4), a through hole (11) being provided on the support plate (10), the through hole (11) being larger than the aperture of the mesh hole on the filter screen (4), an annular connecting plate (12) extending from the support plate (10) towards the filter screen (4) for fixed connection with the filter screen (4), the support plate (10), the filter screen (4) and the connecting plate (12) being arranged to form a receiving space; A bouncing ball (13) is arranged in the accommodating space, and the bouncing ball (13) has elasticity and can bounce along with the vibration of the screening tank (2).

8. The method for preparing a flocculant according to claim 7, characterized in that: A plurality of limiting belts (14) are arranged in the accommodation space. The limiting belts (14) are made of PU material and are in a circular ring shape. At least two bouncing balls (13) are arranged within the range of each limiting belt (14).

9. The method for preparing a flocculant according to claim 8, characterized in that: The upper surface of the limiting belt (14) is provided with a puncture portion (15) in the shape of a needle, and the diameter of the puncture portion (15) is smaller than the mesh diameter of the filter screen (4).

10. The method for preparing a flocculant according to claim 9, characterized in that: The screening machine has three layers of filter screens (4).

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