Ink calcium production process and production device

Abstract

The production process comprises the following steps: a, injecting lime milk into a carbonizer, then introducing carbon dioxide into the carbonizer to enable the lime milk to become calcium carbonate slurry to obtain a product A, and b, transferring the product A to a surface treatment tank, calculating the weight of a calcium carbonate dry material according to the water content of the product A, c, dehydrating the product B to obtain a product C; d, adding ammonia water into the product C, stirring, standing for layering, and taking a solid phase to obtain a product D; and e, dehydrating, drying and crushing the product D to obtain a finished product of the printing ink calcium, wherein the addition amount of the surface treating agent is more than 3% of the dry calcium carbonate material. The preparation method has the advantage that the prepared printing ink calcium can reduce the quantity of agglomerates generated in the printing ink.

Description

Technical Field

[0001] The invention belongs to the field of ink calcium, and in particular relates to an ink calcium production process and a production device. Background Art

[0002] Ink calcium, that is, calcium carbonate used in ink, is in powder form and is required to have excellent dispersibility to avoid flocculent precipitation in the ink.

[0003] The existing production process of ink calcium is to first inject lime milk into a carbonization tower, then pass carbon dioxide into the carbonization tower to turn the lime milk into calcium carbonate slurry, then transfer the slurry to a surface treatment tank, heat it to above 60°C, and add a surface treatment agent (such as resin acid) in an amount of 1%-2% of the dry weight of the slurry, stir for more than half an hour, so that the surface treatment agent is evenly distributed in the slurry, and the surface treatment agent forms a coating layer on the calcium carbonate powder particles, and finally filter the slurry to dehydrate, dry, and crush it to obtain powdered ink calcium. The purpose of adding the surface treatment agent is to reduce the interaction between calcium carbonate molecules so that calcium carbonate can be evenly distributed in the ink.

[0004] In the actual production process, it was found that the existing inks meet the use of printing machines with medium and low printing resolutions. However, when used on high-resolution printing machines, blockage often occurs due to the smaller nozzles of high-resolution printing machines (above 1200dpi). Research has verified that this is mainly caused by the presence of a small amount of agglomerates in the ink, and one of the sources of agglomerates is ink calcium. Some powders in the ink calcium fail to successfully carry the surface treatment agent and cannot be well compatible with other components in the ink, making it difficult to stably disperse in the ink, thereby forming a small amount of agglomerates. According to experiments, the first appearance of agglomerates in the ink that can affect the nozzle is generally about three and a half months. Summary of the invention

[0005] The purpose of the present invention is to provide a process and a device for producing ink calcium. The present invention has the advantage that the ink calcium produced can reduce the amount of agglomerates produced in the ink.

[0006] The technical solution of the present invention is: a process for producing ink calcium, comprising the following steps:

[0007] a. Inject lime milk into the carbonization tower, and then pass carbon dioxide into the carbonization tower to convert the lime milk into calcium carbonate slurry to obtain product A.

[0008] b. Transfer product A to the surface treatment tank, calculate the weight of dry calcium carbonate according to the water content of product A, add surface treatment agent to the surface treatment tank, the amount of surface treatment agent added is more than 3% of dry calcium carbonate, heat to 60℃-70℃, stir evenly, and obtain product B.

[0009] c. Dehydrate product B to obtain product C.

[0010] d. Add ammonia water to product C, stir, let stand and separate into layers, take the solid phase to obtain product D. e. Dehydrate, dry and grind product D to obtain the finished product of ink calcium.

[0011] In the aforementioned ink calcium production process, in the step b, the stirring time is greater than 3 minutes and the stirring speed is above 200 r / min; in the step d, the stirring speed is lower than 30 r / min.

[0012] In the aforementioned ink calcium production process, in the step d, the concentration of the ammonia water is 0.5-1%, and the amount of ammonia water added is more than twice the weight of product C.

[0013] In the aforementioned ink calcium production process, in the step d, the temperature of product C and ammonia water before mixing is controlled so that the temperature of product C and ammonia water after mixing is maintained below 10°C.

[0014] A production device for realizing the aforementioned ink calcium production process, which is used in step d, comprises a sealed tank body, a support foot is provided at the bottom of the top of the tank body, a discharge valve is provided at the bottom of the tank body, a rotating shaft is provided in the tank body, a plurality of stirring components are provided on the rotating shaft, the plurality of stirring components are distributed along the length of the rotating shaft, a driving mechanism connected to the rotating shaft is provided on the top of the tank body, and a feed valve is provided on the top of the tank body.

[0015] In the aforementioned production device, brackets connected to the rotating shaft are provided at the upper and lower ends of the rotating shaft, and the stirring assembly includes a plurality of circumferentially distributed stirring blades, and the stirring blades are twisted to form a spiral shape.

[0016] In the aforementioned production device, the driving mechanism includes a driving shaft, the lower end of the driving shaft is connected to the rotating shaft, the upper end of the driving shaft extends out of the tank body, and the upper end of the driving shaft is connected to a motor.

[0017] In the aforementioned production device, the driving shaft is provided with a first gear and a second gear, a driving main shaft is provided on one side of the driving shaft, a motor whose output end is connected to the driving main shaft is provided on the tank body, a third gear and a fourth gear are provided on the driving main shaft, the third gear and the fourth gear are respectively located on the horizontal side of the first gear and the horizontal side of the second gear, and a fifth gear is provided between the fourth gear and the second gear;

[0018] The teeth on the third gear are distributed on a circumferential surface of the third gear with a wrap angle less than 180°, and the teeth on the fourth gear are distributed on a circumferential surface of the fourth gear with a wrap angle less than 180°;

[0019] A reference plane is constructed with the axis of the driving shaft and the axis of the driving main shaft as references, and the teeth on the third gear and the teeth on the fourth gear are symmetrically distributed about the reference plane.

[0020] In the aforementioned production device, the lower end of the drive shaft extends radially outward to form an upper flange, and a C-shaped upper positioning block is provided on the bottom surface of the upper flange, and the end surfaces at both ends of the upper positioning block pass through the axis of the drive shaft and are located on the same side of the reference plane;

[0021] The upper end of the rotating shaft extends radially outward to form a lower flange, and a C-shaped lower positioning block is provided on the fixed surface of the lower flange. The lower positioning block is located on the horizontal side of the upper positioning block, and the end surfaces at both ends of the lower positioning block pass through the axis of the rotating shaft and are located on the other side of the reference plane;

[0022] The end surfaces of both ends of the upper positioning block are provided with spring cavities, or the end surfaces of both ends of the lower positioning block are provided with spring cavities, and compression springs are arranged in the spring cavities.

[0023] In the aforementioned production device, the wrap angle formed by the end faces of the upper positioning block on the outer circumference of the upper flange is the same as the wrap angle formed by the end faces of the lower positioning block on the outer circumference of the lower flange and both are less than 180°.

[0024] In the aforementioned production device, a positioning shaft is provided between the upper flange and the lower flange.

[0025] Compared with the prior art, the present invention adds steps c and d on the basis of the existing process, and increases the amount of the surface treatment agent in step b. After the above improvements, the success rate of the obtained ink calcium powder carrying the surface treatment agent is improved, and the coating layer formed on the powder has a low thickness, can be stably dispersed in the ink, and agglomerates in the ink are not easy to be generated. After testing, the time for the first appearance of agglomerates in the ink that can affect the nozzle is extended to about five months. Therefore, the present invention has the advantage that the ink calcium prepared can reduce the number of agglomerates generated in the ink.

[0026] In addition, the present invention also provides a production device, which can evenly mix calcium carbonate and a surface treatment agent at a relatively low rotation speed, thereby reducing energy consumption and improving the mixing effect, and the device itself has a relatively low equipment failure rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic front view of the production device.

[0028] Figure 2 Schematic diagram of a top view of the first gear and the third gear.

[0029] Figure 3 Schematic diagram of a top view of the second gear and the fourth gear.

[0030] Figure 4 It is a top view schematic diagram of the connection between the drive shaft and the rotating shaft.

[0031] Figure 5It is a schematic diagram of an explosion where the connection between the drive shaft and the rotating shaft is fixed in one direction.

[0032] Figure 6 It is a schematic diagram of the explosion where the connection between the drive shaft and the rotating shaft is fixed in another direction.

[0033] Figure 7 It is a left view schematic diagram of the connection between the drive shaft and the rotating shaft.

[0034] The marks in the accompanying drawings are: 1-tank body, 2-support foot, 3-discharge valve, 4-rotating shaft, 5-feed valve, 6-bracket, 7-stirring blade, 8-drive shaft, 9-motor, 10-first gear, 11-second gear, 12-drive main shaft, 13-third gear, 14-fourth gear, 15-fifth gear, 19-upper flange, 20-upper positioning block, 21-lower flange, 22-lower positioning block, 23-spring chamber, 24-compression spring, 25-positioning shaft. DETAILED DESCRIPTION

[0035] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0036] Example 1. A process for producing ink calcium, comprising the following steps:

[0037] a. Inject lime milk into the carbonization tower, and then pass carbon dioxide into the carbonization tower to convert the lime milk into calcium carbonate slurry to obtain product A.

[0038] b. Transfer product A to the surface treatment tank, calculate the weight of dry calcium carbonate according to the water content of product A, add surface treatment agent to the surface treatment tank, the surface treatment agent is resin acid, the addition amount of surface treatment agent is more than 3% of dry calcium carbonate, heat to 60℃-70℃, stir evenly, the stirring time is more than 3min, the stirring speed is more than 200r / min, and product B is obtained. c. Dehydrate product B to obtain product C.

[0039] d. Add 0.5-1% ammonia water into product C. The amount of ammonia water added is more than one times the weight of product C. Stir at a speed of less than 30r / min. Let stand for stratification and take the solid phase to obtain product D.

[0040] e. Product D is dehydrated, dried and crushed to obtain the finished product of ink calcium.

[0041] In the step d, the temperature of product C and ammonia water before mixing is controlled so that the temperature of product C and ammonia water after mixing is maintained below 10° C., preferably 8° C.

[0042] Compared with the existing process, the process of Example 1 is different in that steps c and d are added, and the amount of resin acid is increased in step b. By increasing the amount of resin acid, the calcium carbonate particles are more thoroughly coated and less missed. The reason why only 1% to 2% resin acid is used in the existing process is that the continued increase of resin acid may cause the coating layer of some calcium carbonate to be too thick, so that not only the dispersibility is not improved, but it may be reduced, and it will be easier to dissolve in the ink, which may conflict with the ink system components (including binders, solvents, additives, etc.), and even affect the scattering effect of calcium carbonate on light, which has an adverse effect on the transparency of the ink. Therefore, the best choice should be that each calcium carbonate particle should preferably be coated with resin acid, but only a thin layer.

[0043] For this reason, in Example 1, an excess of resin acid is first used to ensure that each calcium carbonate powder particle can be coated with the resin acid as much as possible. The side effect is that a thicker coating layer will be formed, so it is necessary to use extremely low concentration ammonia water to wash the calcium carbonate powder particles. Since there is a chemical bond between the inner layer resin acid and the calcium carbonate powder particles, the bonding force is greater than the dissolving and eluting force of low concentration ammonia water on the resin acid, so that a thin coating layer can be retained on the calcium carbonate powder particles, and the excess part enters the ammonia water.

[0044] Through a large number of experiments, it was found that when ammonia water is used to wash the resin acid coating, the concentration of ammonia water and the temperature during elution are very critical. This is mainly because the chemical properties of ammonia water at different concentrations and temperatures are very different. As the concentration of ammonia water increases, the concentration of resin acid in ammonia water increases. At the same time, the corrosiveness of ammonia water increases, which will cause the coating on the calcium carbonate particles to completely fall off. At 10°C, under a microscope, when the concentration of ammonia water exceeds 8%, the calcium carbonate particles are basically washed away; when the concentration of ammonia water is reduced to 2%, more than 97.4% of the calcium carbonate particles retain the coating; when the concentration of ammonia water is reduced to 1%, basically all calcium carbonate particles retain the coating; after continuing to reduce to 0.5%, the required elution time is too long, exceeding the static stratification time, affecting production efficiency.

[0045] It was also found that the stirring intensity during ammonia washing will also affect the washing effect. The violent collision between the calcium carbonate powder particles, coupled with the dissolving and elution power of ammonia water, will cause the chemical bonds between the resin acid and the calcium carbonate powder particles to break, resulting in the complete falling off of the coating on the calcium carbonate powder particles. Therefore, low-speed stirring should be used.

[0046] In a large number of experiments, different surface treatment agents were selected and used. The best effect was achieved when resin acid and ammonia water were used together. When other substances were used as surface treatment agents, other substances may need to be used instead of ammonia water.

[0047] Embodiment 2. A production device for implementing embodiment 1, used in step d, comprises a sealed tank body 1, a support foot 2 is provided at the bottom of the top of the tank body 1, a discharge valve 3 is provided at the bottom of the tank body 1, a rotating shaft 4 is provided inside the tank body 1, a plurality of stirring assemblies are provided on the rotating shaft 4, and the plurality of stirring assemblies are distributed along the length of the rotating shaft 4, a driving mechanism connected to the rotating shaft 4 is provided at the top of the tank body 1, and a feed valve 5 is provided at the top of the tank body 1.

[0048] The upper and lower ends of the rotating shaft 4 are both provided with brackets 6 rotatably connected to the rotating shaft 4, and the stirring assembly includes a plurality of circumferentially distributed stirring blades 7, and the stirring blades 7 are twisted to form a spiral shape. The stirring assembly is a common structure for driving fluid movement.

[0049] The driving shaft 8 is provided with a first gear 10 and a second gear 11, a driving main shaft 12 is provided on one side of the driving shaft 8, a motor 9 whose output end is connected to the driving main shaft 12 is provided on the tank body 1, the rotation speed of the motor 9 is 25r / min, and a third gear 13 and a fourth gear 14 are provided on the driving main shaft 12, the third gear 13 and the fourth gear 14 are respectively located on the horizontal side of the first gear 10 and the horizontal side of the second gear 11, a fifth gear 15 is provided between the fourth gear 14 and the second gear 11, and the fifth gear 15 is rotationally connected to the tank body 1.

[0050] The teeth on the third gear 13 are distributed on a circumferential surface of the third gear 13 with an angle of 170°, and the teeth on the fourth gear 14 are distributed on a circumferential surface of the fourth gear 14 with an angle of 170°.

[0051] A reference plane is constructed with the axis of the driving shaft 8 and the axis of the driving main shaft 12 as references, and the teeth on the third gear 13 and the teeth on the fourth gear 14 are symmetrically distributed about the reference plane.

[0052] The lower end of the drive shaft 8 extends radially outward to form an upper flange 19. A C-shaped upper positioning block 20 is provided on the bottom surface of the upper flange 19. The end surfaces of both ends of the upper positioning block 20 pass through the axis of the drive shaft 8 and are located on the same side of the reference plane.

[0053] The upper end of the rotating shaft 4 extends radially outward to form a lower flange 21. A C-shaped lower positioning block 22 is provided on the fixed surface of the lower flange 21. The lower positioning block 22 is located on the horizontal side of the upper positioning block 20. The end faces at both ends of the lower positioning block 22 pass through the axis of the rotating shaft 4 and are located on the other side of the reference plane.

[0054] Spring cavities 23 are provided on the end surfaces of both ends of the upper positioning block 20 , and compression springs 24 are provided in the spring cavities 23 .

[0055] The wrap angles formed by the end surfaces of both ends of the upper positioning block 20 on the outer peripheral surface of the upper flange 19 and the wrap angles formed by the end surfaces of both ends of the lower positioning block 22 on the outer peripheral surface of the lower flange 21 are both 170°.

[0056] A positioning shaft 25 is provided between the upper flange 19 and the lower flange 21, the lower end of the positioning shaft 25 is fixed to the lower flange 21, and the upper end of the positioning shaft 25 is inserted into the upper flange 19. The positioning shaft 25 is used to keep the rotating shaft 4 and the driving shaft 8 coaxial.

[0057] Working principle: Product C and ammonia water enter the tank body 1 from the feed valve 5. To maintain the temperature, insulation materials can be installed on the outer wall of the tank body 1, or cooling equipment can be installed to keep the temperature of the tank body 1 below 10°C.

[0058] The motor 9 rotates the driving spindle 12, and the driving spindle 12 rotates the third gear 13 and the fourth gear 14 synchronously. When the teeth on the third gear 13 mesh with the first gear 10, the teeth on the fourth gear 14 do not mesh with the fifth gear 15, and the power of the driving spindle 12 is transmitted to the first gear 10 through the third gear 13, driving the driving shaft 8 to rotate forward, and the driving shaft 8 drives the stirring blade 7 to rotate forward through the rotating shaft 4, so that the ammonia water and the C product are mixed evenly; when the teeth on the third gear 13 are disengaged from the first gear 10, the teeth on the fourth gear 14 mesh with the fifth gear 15, and the power of the driving spindle 12 is transmitted to the second gear 11 through the fourth gear 14 and the fifth gear 15, driving the driving shaft 8 to reverse, so that the stirring blade 7 is reversed. In one minute, the stirring blade 7 rotates forward and backward 25 times, so that a stirring effect similar to hand rubbing is formed in the tank body 1, and the stirring force is small, but the stirring is very uniform.

[0059] Since the teeth on the third gear 13 are distributed on the circumference of the third gear 13 with an angle of 170°, the teeth on the fourth gear 14 are distributed on the circumference of the fourth gear 14 with an angle of 170°, and the angles formed by the end faces of the upper positioning block 20 on the outer circumference of the upper flange 19 and the angles formed by the end faces of the lower positioning block 22 on the outer circumference of the lower flange 21 are both 170°. When the power transmission between the third gear 13 and the first gear 10 is disconnected, the inertial energy of the stirring blade 7 will be absorbed by the compression spring 24, which will promote the stirring blade 7 to change direction, and then the fourth gear 14 and the fifth gear 15 will re-establish power transmission, thereby reducing energy consumption, inertial impact, and equipment failure rate; similarly, when the power transmission between the fourth gear 14 and the fifth gear 15 is disconnected, the inertial energy of the stirring blade 7 will also be absorbed by the compression spring 24.

[0060] After the stirring operation is completed, the mixture is allowed to stand for a period of time, and the solid phase sediment at the bottom of the tank body 1 is taken out through the discharge valve 3 .

Claims

1. A process for producing ink calcium, characterized in that: The following steps are included: a. Inject lime milk into the carbonization tower, and then pass carbon dioxide into the carbonization tower to convert the lime milk into calcium carbonate slurry to obtain product A. b. Transfer product A to the surface treatment tank, calculate the weight of dry calcium carbonate according to the water content of product A, add surface treatment agent to the surface treatment tank, the amount of surface treatment agent added is more than 3% of dry calcium carbonate, heat to 60℃-70℃, stir evenly, and obtain product B. c. Dehydrate product B to obtain product C. d. Add ammonia water to product C, stir, let stand and separate, take the solid phase, and obtain product D. e. Product D is dehydrated, dried and crushed to obtain the finished product of ink calcium.

2. The ink calcium production process according to claim 1, characterized in that: In the step b, the stirring time is greater than 3 minutes and the stirring speed is greater than 200 r / min; in the step d, the stirring speed is lower than 30 r / min.

3. The ink calcium production process according to claim 1, characterized in that: In the step d, the concentration of the ammonia water is 0.5-1%, and the amount of ammonia water added is more than one times the weight of product C.

4. The ink calcium production process according to claim 1, characterized in that: In the step d, the temperature of product C and ammonia water before mixing is controlled so that the temperature of product C and ammonia water after mixing is maintained below 10°C.

5. A production device for realizing the ink calcium production process according to claim 1, 2, 3 or 4, characterized in that: The production device is used in step d, comprising a sealed tank body (1), the bottom of the top of the tank body (1) is provided with a support foot (2), the bottom of the tank body (1) is provided with a discharge valve (3), a rotating shaft (4) is provided inside the tank body (1), a plurality of stirring components are provided on the rotating shaft (4), and the plurality of stirring components are distributed along the length of the rotating shaft (4), a driving mechanism connected to the rotating shaft (4) is provided on the top of the tank body (1), and a feed valve (5) is provided on the top of the tank body (1); the upper and lower ends of the rotating shaft (4) are both provided with brackets (6) connected to the rotating shaft (4), and the stirring component includes a plurality of circumferentially distributed stirring blades (7), and the stirring blades (7) are twisted to form a spiral shape.

6. The production device according to claim 5, characterized in that: The driving mechanism comprises a driving shaft (8), the lower end of the driving shaft (8) is connected to the rotating shaft (4), the upper end of the driving shaft (8) extends out of the tank body (1), and the upper end of the driving shaft (8) is connected to a motor (9).

7. The production device according to claim 6, characterized in that: The driving shaft (8) is provided with a first gear (10) and a second gear (11); a driving main shaft (12) is provided on one side of the driving shaft (8); a motor (9) whose output end is connected to the driving main shaft (12) is provided on the tank body (1); a third gear (13) and a fourth gear (14) are provided on the driving main shaft (12); the third gear (13) and the fourth gear (14) are respectively located on the horizontal side of the first gear (10) and the horizontal side of the second gear (11); and a fifth gear (15) is provided between the fourth gear (14) and the second gear (11); The teeth on the third gear (13) are distributed on a circumferential surface of the third gear (13) with an angle less than 180°, and the teeth on the fourth gear (14) are distributed on a circumferential surface of the fourth gear (14) with an angle less than 180°; A reference plane is constructed with the axis of the drive shaft (8) and the axis of the drive main shaft (12) as references, and the teeth on the third gear (13) and the teeth on the fourth gear (14) are symmetrically distributed about the reference plane.

8. The production device according to claim 7, characterized in that: The lower end of the drive shaft (8) extends radially outward to form an upper flange (19), and a C-shaped upper positioning block (20) is provided on the bottom surface of the upper flange (19), and the end surfaces at both ends of the upper positioning block (20) pass through the axis of the drive shaft (8) and are located on the same side of the reference plane; The upper end of the rotating shaft (4) extends radially outward to form a lower flange (21), and a C-shaped lower positioning block (22) is provided on a fixed surface of the lower flange (21). The lower positioning block (22) is located on the horizontal side of the upper positioning block (20), and the end surfaces at both ends of the lower positioning block (22) pass through the axis of the rotating shaft (4) and are located on the other side of the reference plane; The end surfaces of both ends of the upper positioning block (20) are provided with spring cavities (23), or the end surfaces of both ends of the lower positioning block (22) are provided with spring cavities (23), and compression springs (24) are provided in the spring cavities (23).

9. The production device according to claim 8, characterized in that: The wrap angle formed by the end faces of the upper positioning block (20) at both ends on the outer peripheral surface of the upper flange (19) is the same as the wrap angle formed by the end faces of the lower positioning block (22) at both ends on the outer peripheral surface of the lower flange (21), and both are less than 180 degrees.

10. The production device according to claim 8, characterized in that: A positioning shaft (25) is provided between the upper flange (19) and the lower flange (21).

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