A blending pre-granulation device and a pre-granulation method

Abstract

The application discloses a mixing and uniformizing pre-granulation device and a pre-granulation method. The mixing and uniformizing pre-granulation device comprises a rotating barrel, a stirring mechanism and a granulating mechanism arranged in the rotating barrel. The stirring mechanism comprises a stirring shaft and a stirring paddle. The granulating mechanism comprises a rotating shaft and a propeller. The rotating directions of the stirring mechanism and the granulating mechanism are opposite, and the rotating directions of the stirring mechanism and the rotating barrel are also opposite. The stirring paddle throws the mixed and uniformized material to the propeller, and the propeller granulates the mixed and uniformized material. The mixing and uniformizing pre-granulation device and the pre-granulation method disclosed by the application simultaneously arrange the stirring mechanism and the granulating mechanism in the rotating barrel. The stirring mechanism cuts and convects the material to stir and mix the material in the granulating chamber, and then throws the material to the granulating mechanism. The propeller of the granulating mechanism granulates the material in the rotating process, and solves the problems that the water is added to granulate in the prior art, the strength of the powder and particle is not enough, the quality is poor, and the efficiency is low.

Description

Technical Field

[0001] This invention relates to the field of material mixing and granulation technology, and in particular to a mixing and pre-granulation device and a pre-granulation method. Background Technology

[0002] In the industrial sector, there are numerous processes for granulating mixed powders, such as pelletizing raw materials in the steel industry. The key process in powder pelletizing is the generation of pellet nuclei (also known as mother pellets). The pelletizing process involves the continuous growth of these nuclei until they meet industrial requirements. Without nuclei, pelletizing is impossible; the more nuclei present, the higher the pelletizing efficiency.

[0003] Disc pelletizers are commonly used for pelletizing raw materials. After the uniformly mixed material enters the disc pelletizer, it begins to nucleate and grow. Due to the small particle size of the raw materials (over 90% are -200 mesh), the number of pellet nuclei is significantly insufficient during disc pelletizing. External pellet nuclei must be added to improve pelletizing efficiency and meet production requirements. The common practice is to add water; water droplets can agglomerate surrounding fine particles, forming powder agglomerates that then act as pellet nuclei. However, adding water can result in insufficient agglomerate strength, affecting pelleting quality. Furthermore, the moisture content of the raw materials is limited by the production process and can only be added moderately. Therefore, adding external pellet nuclei cannot completely solve the problem of insufficient pellet nuclei in the mixture, leading to low efficiency and low output of the disc pelletizer.

[0004] Therefore, it is necessary to propose a mixing pre-granulation device and a pre-granulation method to solve the above-mentioned defects. Summary of the Invention

[0005] The main objective of this invention is to provide a mixing and pre-granulation device and a pre-granulation method, which aims to solve the problem that existing disc pelletizers, when using water to address insufficient pellet core quality, result in insufficient pellet strength and thus affect granulation quality.

[0006] To achieve the above objectives, the present invention provides a mixing pre-granulation device, which includes a rotating drum, a stirring mechanism, and a granulation mechanism. The rotating drum has a granulation chamber inside, and a feed inlet and a discharge outlet are respectively provided at the top and bottom of the rotating drum. The stirring mechanism and the granulation mechanism are installed in the granulation chamber at intervals from each other. The stirring mechanism includes a stirring shaft and a stirring paddle mounted on the stirring shaft. The granulation mechanism includes a rotating shaft and a propeller mounted on the rotating shaft. The stirring mechanism and the granulation mechanism rotate in opposite directions, and the stirring mechanism and the rotating drum also rotate in opposite directions. During rotation, the stirring paddle throws the material it has mixed toward the propeller, and the propeller forms the mixed material into granules during rotation.

[0007] Preferably, the stirring paddle includes a plurality of stirring blades, and the stirring blades are arranged alternately along the axial direction of the stirring shaft.

[0008] Preferably, the stirring blade includes a body portion and a receiving portion, the body portion is mounted on the stirring shaft and extends radially toward the stirring shaft at both ends, and the receiving portion is obliquely fixed to the body portion.

[0009] Preferably, the pelleting mechanism is vertically suspended at the top of the rotating drum and located above the discharge port, wherein,

[0010] The distance between the granulation mechanism and the bottom of the rotating drum is 5mm to 15mm.

[0011] Preferably, there is at least one stirring mechanism and one granulation mechanism, with the stirring mechanism located around the periphery of the granulation mechanism.

[0012] Preferably, a wall scraper is provided inside the rotating barrel, and the blade of the wall scraper is spaced apart from the inner wall of the rotating barrel.

[0013] Preferably, the blade of the barrel wall scraper is 5mm to 10mm away from the inner wall of the rotating barrel.

[0014] Preferably, the bottom of the rotating drum is equipped with a discharge disc for controlling the opening of the discharge port.

[0015] The present invention also provides a method for mixing and pre-granulating, comprising the following steps:

[0016] Preferably, in step S1, the average particle size range and mass percentage range of the material are preset;

[0017] Step S2: Set the initial rotation speed of the granulation mechanism and the stirring mechanism;

[0018] Step S3: Start the device and feed the material into the rotating drum through the feed inlet to begin mixing and pre-granulation.

[0019] Step S4: Detect whether the average particle size and mass percentage of the granulated material are within a preset range. When the detected average particle size and mass percentage are within the preset range, the rotation speed of the granulation mechanism and the stirring mechanism remains unchanged. When the detected average particle size and mass percentage exceed the preset range, the rotation speed of the granulation mechanism and the stirring mechanism are adjusted respectively.

[0020] Preferably, in step S4:

[0021] When the detected average particle size and mass percentage are both greater than the preset values, the rotation speed of the stirring mechanism is increased while the rotation speed of the granulation mechanism is decreased.

[0022] When the detected average particle size is greater than the maximum value of the preset range and the mass percentage is within the preset range, the rotation speed of the stirring mechanism remains unchanged, and the rotation speed of the pelletizing mechanism is reduced.

[0023] When the detected average particle size is greater than the maximum value of the preset range and the mass percentage is less than the minimum value of the preset range, the rotation speed of the granulation mechanism is kept constant while the rotation speed of the stirring mechanism is increased.

[0024] When the detected average particle size is within the preset range and the mass percentage is greater than the maximum value of the preset range, the rotation speed of the stirring mechanism is kept constant while the rotation speed of the pelletizing mechanism is reduced.

[0025] When the detected average particle size and mass percentage are both within the preset range, the rotation speed of the stirring mechanism and the granulation mechanism remains unchanged.

[0026] When the detected average particle size is within the preset range and the mass percentage is less than the minimum value of the preset range, the rotation speed of the stirring mechanism remains unchanged, and the rotation speed of the pelletizing mechanism is increased.

[0027] When the detected average particle size is less than the minimum value of the preset range and the mass percentage is greater than the maximum value of the preset range, the rotation speed of the pelletizing mechanism is kept constant while the rotation speed of the stirring mechanism is reduced.

[0028] When the detected average particle size is less than the minimum value of the preset range and the mass percentage is within the preset range, the rotation speed of the stirring mechanism remains unchanged, and the rotation speed of the granulation mechanism is increased.

[0029] When the detected average particle size and mass percentage are both less than the minimum value of the preset range, the rotation speed of the granulation mechanism is increased while the rotation speed of the stirring mechanism is decreased.

[0030] Compared with the prior art, the mixing pregranulation device and pregranulation method provided by the present invention have the following beneficial effects:

[0031] The mixing and pre-granulation device and method provided by this invention simultaneously arranges a stirring mechanism and a granulation mechanism in a rotating drum. The stirring mechanism and the granulation mechanism rotate in opposite directions, and the rotation directions of the stirring mechanism and the rotating drum are also opposite. This allows the stirring mechanism to perform material cutting and convection motion to mix the material in the granulation chamber before throwing the material towards the granulation mechanism. The propeller of the granulation mechanism forms the material into granules during rotation, which greatly improves granulation efficiency and produces high-quality granules. This solves the problem of insufficient powder and granule strength, poor quality, and low efficiency caused by adding water to granulate in the prior art. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0033] Figure 1 This is a side view of the mixing pre-granulation device provided by the present invention;

[0034] Figure 2 for Figure 1 A top view of the mixing and pre-granulation device shown;

[0035] Figure 3 for Figure 1 The diagram shows the structure of the stirring blade;

[0036] Figure 4 for Figure 1 A schematic diagram showing the installation position of the agitator;

[0037] Figure 5 for Figure 1 The diagram shown is a structural schematic of the granulation mechanism.

[0038] Figure 6 for Figure 1 A schematic diagram of the two stirring mechanisms in the mixing pre-granulation device shown;

[0039] Figure 7 for Figure 1 The diagram shows the structure of the three stirring mechanisms in the mixing pre-granulation device.

[0040] Figure 8 for Figure 1 The diagram shows the structure of the unloading disc and control components.

[0041] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0042] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0044] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0045] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0046] Please refer to the following: Figure 1 and Figure 2 This invention provides a mixing and pre-granulation device. The mixing and pre-granulation device includes a rotating drum 1, a stirring mechanism 3, and a granulation mechanism 5. The stirring mechanism 3 and the granulation mechanism 5 are spaced apart and both are installed inside the rotating drum 1. A fixed support 7 is installed above the rotating drum 1, and both the granulation mechanism 5 and the stirring mechanism 3 are fixed to the fixed support 7. A driver installed outside the rotating drum 1 drives the stirring mechanism 3 and the granulation mechanism 5 to rotate inside the rotating drum 1. Specifically, the driver is a motor.

[0047] Specifically, the rotating drum 1 is cylindrical, and a granulation chamber 11 is formed inside the rotating drum 1. The top and bottom of the rotating drum 1 are respectively provided with a feed inlet 13 and a discharge outlet 15. Both the stirring mechanism 3 and the granulation mechanism 5 are installed inside the granulation chamber 11 to complete the granulation process. Material enters from the feed inlet 13 of the rotating drum 1, and after granulation, it is discharged from the discharge outlet 15. The rotating drum 1 is also driven by a driver to rotate around its axis in the opposite direction to the rotation of the stirring mechanism 3. The movement direction of the material inside the drum is opposite to the rotation of the stirring mechanism 3, thereby causing the stirring mechanism 3 to perform a cutting action on the material to achieve the purpose of stirring and mixing the material.

[0048] Furthermore, the stirring mechanism 3 includes a stirring shaft 31 and a stirring paddle 33 mounted on the stirring shaft 31. The stirring shaft 31 is driven to rotate by a driver. Under the drive of the stirring shaft 31, the stirring paddle 33 makes a cutting motion with the material to stir and mix the material. Under the drive of the stirring shaft 31, the rotation direction of the stirring paddle 33 is opposite to the movement direction of the rotating drum 1, thereby forming a cutting and convection motion between the material and the stirring paddle 33, which fully disperses and mixes the material.

[0049] like Figure 4 As shown, the stirring paddle 33 includes a plurality of stirring blades, which are arranged alternately along the axial direction of the stirring shaft. This ensures that the stirring blades at different positions and heights have more thorough contact with the material, resulting in better mixing.

[0050] like Figure 3 As shown, the stirring blade includes a body portion 371 and a receiving portion 373. The body portion 371 is mounted on the stirring shaft 31 and extends radially toward the stirring shaft 31 from opposite ends. The receiving portion 373 is obliquely fixed to the body portion 371. The receiving portion 373 is a wedge-shaped structure with a downward trend. The rotation direction of the stirring blade is opposite to the movement direction of the material. Therefore, when the wedge-shaped receiving portion 373 comes into contact with the material, it generates a collision force that throws the material toward the granulation mechanism 5. In the working area of ​​the stirring mechanism 3, the body portion 371 rapidly cuts the material and drives the surrounding material to be thrown toward the granulation mechanism 5 along the material discharge direction under the action of the receiving portion 373. Together with the rotating drum 1, it arouses intense cutting, convection, and diffusion mixing of the material, achieving efficient mixing of raw materials. The faster the rotation speed of the stirring mechanism 3, the more intense the material cutting and crushing, and the better the mixing effect.

[0051] The granulation mechanism 5 rotates in the opposite direction to the stirring mechanism 3. The granulation mechanism 5 includes a rotating shaft 51 and a propeller 53 mounted on the rotating shaft 51. Figure 2 As shown, the rotating shaft 51 is driven to rotate by another driver. Figure 5 As shown, the propeller 53 moves in a spiral motion under the drive of the rotating shaft 51. The spiral blades present a three-dimensional space. In the working area of ​​the granulation mechanism 5, the blades of the granulation mechanism 5 throw the mixed material towards the propeller 53 during rotation. The propeller 53 impacts and collides with the material, causing the material to generate forces F1 and F2. The two forces work together to make the material roll in three-dimensional space. During the rotation of the propeller 53, the mixed material is granulated into particles, so that the fine particles on the adhesion path can quickly grow into nuclei. The faster the rotation speed of the granulation mechanism 5, the more granulated particles there are and the larger the particle size.

[0052] The rotating shaft 51 of the granulation mechanism 5 is vertically suspended at the top of the rotating drum 1 and located above the discharge port 15. The spiral 53 is wound around the suspended rotating shaft 51. The distance between the end of the spiral 53 away from the fixed support 7 and the bottom of the rotating drum 1 is 5mm-15mm.

[0053] The granulation mechanism 5 is a single unit, fixed cantilevered above the discharge port 15. The stirring mechanism 3 is at least one unit, located around the periphery of the granulation mechanism 5. Figure 2 , Figure 6 and Figure 7 As shown, the stirring mechanism 3 can be one, two, or three, such as... Figure 2 As shown, when there is only one stirring mechanism 3, the granulation mechanism 5 and the stirring mechanism 3 are arranged in parallel, as follows: Figure 6 As shown, when there are two stirring mechanisms 3, the two stirring mechanisms 3 are distributed on both sides of the granulation mechanism 5, as follows: Figure 7 As shown, when there are three stirring mechanisms 3, the three stirring mechanisms 3 are distributed around the periphery of the granulation mechanism 5. Therefore, there is only one granulation mechanism 5, and the stirring mechanism 3 can be one or more. The more stirring mechanisms 3 there are, the higher the mixing efficiency. It is worth mentioning that, in various modes, the radial end of the propeller 53 always covers the center of the discharge port 15, so that the material mixed with the particles formed and nucleated by the granulation mechanism 5 is quickly discharged from the discharge port 15.

[0054] The rotating drum 1 is equipped with a drum wall scraper 8, the blade of which is positioned at a certain distance from the drum wall, specifically 5mm to 10mm from the inner wall of the rotating drum 1. The drum wall scraper 8 is fixed, and as the rotating drum 1 rotates, the drum wall scrape off excess material adhering to the side wall of the rotating drum 1, preventing material from continuously accumulating and adhering to the wall surface.

[0055] A discharge disc 9 for controlling the opening of the discharge port 15 is installed at the bottom of the rotating drum 1. The discharge disc 9 is fixedly installed at the bottom of the rotating drum 1 and is connected to a control component 10. The control component 10 controls the rotation of the discharge disc, thereby controlling the opening of the discharge port 15. Specifically, as shown... Figure 8As shown, the control assembly 10 includes a tilting plate 101 mounted on the bottom of the rotating drum 1, a hydraulic push rod 103 rotatably connected to the tilting plate 101, and a telescopic screw 105 detachably connected to the tilting plate 101. The telescopic screw 105 is detachably connected to the tilting plate 101. The hydraulic push rod 103 and the telescopic screw 105 are used to control the rotation of the tilting plate 101, thereby controlling the opening of the discharge port 15. The hydraulic push rod 103 is for automatic control, and the telescopic screw 105 is for manual control. When the hydraulic push rod 103 is in automatic control, the telescopic screw 105 is in a detached state. When the hydraulic push rod 103 fails, the telescopic screw 105 can be installed to control the tilting plate 101.

[0056] In detail, the hydraulic push rod 103 is connected to the hydraulic system, and the flow rate of the hydraulic system is adjustable, thereby controlling the extension and retraction length of the hydraulic push rod 103. Thus, by controlling the flow rate, the rotation angle of the unloading disc 9 can be precisely controlled to control the opening of the discharge port 15, thereby achieving the purpose of automatically controlling the opening of the discharge port 15.

[0057] A handle 107 is installed on the telescopic screw 105. The handle is rotated to control the extension and retraction of the telescopic screw 105. It should be noted that the telescopic screw 105 is connected to the flip plate 101 by a pin. The installation and removal of the telescopic screw 105 and the flip plate 101 are achieved by inserting and removing the pin.

[0058] Therefore, the control component 10 can effectively realize the manual and automatic control of the unloading disc, ensuring the fluidity of the material, as well as the mixing time and the mixing effect.

[0059] In another embodiment, the present invention also provides a method for mixing and pre-granulating, comprising the following steps:

[0060] Step S1: Preset the average particle size range and mass percentage range of the material.

[0061] Step S2: Set the initial rotation speed of the granulation mechanism 5 and the stirring mechanism 3.

[0062] Step S3: Start the device and feed the material into the rotating drum 1 through the feed port 13 to begin mixing and pre-granulation.

[0063] Step S4: Detect whether the average particle size and mass percentage of the granulated material are within a preset range. When the detected average particle size and mass percentage are within the preset range, the rotation speed of the granulation mechanism 5 and the stirring mechanism 3 remains unchanged. When the detected average particle size and mass percentage exceed the preset range, the rotation speed of the granulation mechanism 5 and the stirring mechanism 3 are adjusted respectively.

[0064] Furthermore, in step S4, when the detected average particle size value and mass percentage value are both greater than preset values, the rotation speed of the stirring mechanism 3 is increased while the rotation speed of the granulation mechanism 5 is decreased.

[0065] When the detected average particle size is greater than the maximum value of the preset range and the mass percentage is within the preset range, the rotation speed of the stirring mechanism 3 is kept constant, and the rotation speed of the granulation mechanism 5 is reduced.

[0066] When the detected average particle size is greater than the maximum value of the preset range and the mass percentage is less than the minimum value of the preset range, the rotation speed of the granulation mechanism 5 is kept constant, and the rotation speed of the stirring mechanism 3 is increased.

[0067] When the detected average particle size is within the preset range and the mass percentage is greater than the maximum value of the preset range, the rotation speed of the stirring mechanism 3 is kept constant while the rotation speed of the granulation mechanism 5 is reduced.

[0068] When the detected average particle size and mass percentage are both within the preset range, the rotation speed of the stirring mechanism 3 and the granulation mechanism 5 remains unchanged.

[0069] When the detected average particle size is within the preset range and the mass percentage is less than the minimum value of the preset range, the rotation speed of the stirring mechanism 3 is kept constant, and the rotation speed of the granulation mechanism 5 is increased.

[0070] When the detected average particle size is less than the minimum value of the preset range and the mass percentage is greater than the maximum value of the preset range, the rotation speed of the granulation mechanism 5 is kept constant while the rotation speed of the stirring mechanism 3 is reduced.

[0071] When the detected average particle size is less than the minimum value of the preset range and the mass percentage is within the preset range, the rotation speed of the stirring mechanism 3 is kept constant, and the rotation speed of the granulation mechanism 5 is increased.

[0072] When the detected average particle size and mass percentage are both less than the minimum value of the preset range, the rotation speed of the granulation mechanism 5 is increased while the rotation speed of the stirring mechanism 3 is decreased.

[0073] The average particle size is defined as d0, with a preset range of [dmin, dmax]. The mass percentage is defined as η0, with a mass percentage range of [ηmin, ηmax]. The initial rotation speed of the granulation mechanism 5 is defined as Z0 (r / min), and the initial rotation speed of the stirring mechanism 3 is defined as Y0 (r / min). Therefore, when d0 > dmax and η0 > ηmax, the rotation speed of the stirring mechanism 3 is increased while the rotation speed of the granulation mechanism 5 is decreased until d0 ∈ [dmin, dmax] and η0 ∈ [ηmin, ηmax].

[0074] When d0 > dmax and η0 ∈ [ηmin, ηmax], keep the rotation speed of the stirring mechanism 3 unchanged and reduce the rotation speed of the granulation mechanism 5 until d0 ∈ [dmin, dmax] and η0 ∈ [ηmin, ηmax].

[0075] When d0 > dmax and η0 < ηmin, keep the rotation speed of the granulation mechanism 5 unchanged and increase the rotation speed of the stirring mechanism 3 until d0 ∈ [dmin, dmax] and η0 ∈ [ηmin, ηmax].

[0076] When d0 ∈ [dmin, dmax] and η0 > ηmax, keep the rotation speed of the stirring mechanism 3 unchanged and reduce the rotation speed of the granulation mechanism 5 until d0 ∈ [dmin, dmax] and η0 ∈ [ηmin, ηmax].

[0077] When d0 ∈ [dmin, dmax] and η0 ∈ [ηmin, ηmax], maintain the current state unchanged;

[0078] When d0 ∈ [dmin, dmax] and η0 < ηmin, keep the rotation speed of the stirring mechanism 3 unchanged and increase the rotation speed of the granulation mechanism 5 until d0 ∈ [dmin, dmax] and η0 ∈ [ηmin, ηmax].

[0079] When d0 < dmin and η0 > ηmax, keep the rotation speed of the granulation mechanism 5 unchanged and reduce the rotation speed of the stirring mechanism 3 until d0 ∈ [dmin, dmax] and η0 ∈ [ηmin, ηmax].

[0080] When d0 < dmin and η0 ∈ [ηmin, ηmax], keep the rotation speed of the stirring mechanism 3 unchanged and increase the rotation speed of the rotary granulation mechanism 51 until d0 ∈ [dmin, dmax] and η0 ∈ [ηmin, ηmax].

[0081] When d0 < dmin and η0 < ηmin, increase the rotation speed of the granulation mechanism 5 and reduce the rotation speed of the stirring mechanism 3 until d0 ∈ [dmin, dmax] and η0 ∈ [ηmin, ηmax].

[0082] Specifically, when d0 > dmax and η0 > ηmax,

[0083] Specifically, when d0 > 150% dmax and η0 > 150% ηmax,

[0084] When d0 > 150% dmax and 150% ηmax ≥ η0 > ηmax,

[0085] When 150%dmax≥d0>dmax, η0>150%ηmax

[0086] When 150%dmax≥d0>dmax and 150%ηmax≥η0>ηmax

[0087] In the formula: k1, k2, k3, k4, e1, e2, e3, e4 are speed adjustment coefficients, k1 ranges from 0.7 to 0.9, k2 ranges from 0.5 to 0.7, e1 ranges from 0.5 to 0.7, e2 ranges from 0.3 to 0.5, e1 ranges from 0.9 to 1.2, e2 ranges from 0.6 to 0.9, e3 ranges from 0.6 to 0.9, e4 ranges from 0.3 to 0.6, Z0 and Y0 are the initial speeds of the stirring shaft and the rotating shaft, and Z1 and Y1 are the adjusted speeds of the stirring shaft and the rotating shaft.

[0088] When d0>dmax, η0∈[ηmin,ηmax]

[0089] Specifically, when d0 > 150% dmax Y1 = Y0

[0090] When 150%dmax≥d0>dmax, Y1 = Y0

[0091] In the formula: k5 and k6 are speed adjustment coefficients, the value range of k3 is 0.7-0.95, and the value range of k4 is 0.45-0.7.

[0092] When d0 > dmax, η0 < ηmin

[0093] Specifically, when d0 > 150%dmax and 50%ηmin ≥ η0n, Z1 = Z0.

[0094] Specifically, when d0 > 150%dmax and ηmin > η0 > 50%ηmi, Z1 = Z0.

[0095] Specifically, when 150%dmax≥d0>dmax and ηmin>η0>50%ηmin, Z1=Z0.

[0096] Specifically, when 150%dmax≥d0>dmax and 50%ηmin≥η0, Z1=Z0.

[0097] In the formula: e5, e6, e7, and e8 are speed adjustment coefficients, with e5 ranging from 0.8 to 1, e6 ranging from 0.6 to 0.8, e7 ranging from 0.6 to 0.8, and e8 ranging from 0.4 to 0.6.

[0098] When d0∈[dmin, dmax], η0>ηmax.

[0099] Specifically, this applies when η0 > 150%ηmax and 150%ηmax ≥ η0 > ηmax. Y1 = Y0

[0100] Y1 = Y0

[0101] In the formula: k7 and k8 are speed adjustment coefficients, with k7 ranging from 0.65 to 0.9 and k8 ranging from 0.3 to 0.65.

[0102] d0∈[dmin,dmax], when η0<ηmin

[0103] When 50%ηmin > η0 Y1 = Y0

[0104] When ηmin>η0>50%ηmin Y1 = Y0

[0105] In the formula: k9 and k10 are speed adjustment coefficients, with k9 ranging from 0.8 to 1.1 and k10 ranging from 0.5 to 0.8.

[0106] When d0<dmin,η0> When ηmax

[0107] When 50%≤d0<dmin,150%η≥maxη0> When ηmax, Z1=Z0,

[0108] When 50%≤d0<dmin,η0> When ηmax is 150%, Z1 = Z0.

[0109] When d0 < 50%dmin and η0 > 150%ηmax, Z1 = Z0.

[0110] When d0 < 50%dmin and 150%η≥maxη0 > ηmax, Z1 = Z0.

[0111] Where: e9, e10, e11, e12 are speed regulation coefficients. The value range of e9 is 0.7 - 0.95, the value range of e10 is 0.55 - 0.7, the value range of e11 is 0.55 - 0.7, and the value range of e12 is 0.3 - 0.55.

[0112] When d0 < dmin and η0 ∈ [ηmin, ηmax],

[0113] When 50% dmin ≤ d0 < dmin, Y1 = Y0

[0114] When d0 < 50% dmin, Y1 = Y0

[0115] Where: k11, k12 are speed regulation coefficients. The value range of k11 is 0.4 - 0.8, and the value range of k12 is 0.8 - 1.2.

[0116] When d0 < dmin and η0 < ηmin,

[0117] When 50% dmin ≤ d0 < dmin and 50% ηmin ≤ η0 < ηmin;

[0118] When 50% dmin ≤ d0 < dmin and η0 < 50% ηmin;

[0119] When d0 < 50% dmin and 50% ηmin ≤ η0 < ηmin; <0​​​​​​​The mixing and pre-granulation device and method provided by the present invention simultaneously set up a stirring mechanism 3 and a granulation mechanism 5 in a rotating drum 1. The stirring mechanism 3 rotates in the opposite direction to the granulation mechanism 5 and the rotating drum 1, so that the stirring mechanism 3 performs material cutting and convection motion to stir and mix the material in the granulation chamber 11 and then throws the material towards the granulation mechanism 5. The propeller 53 of the granulation mechanism 5 forms the material into granules during the rotation process, which greatly improves the granulation efficiency and the granulation quality. It solves the problem of insufficient powder and granule strength, poor quality and low efficiency caused by adding water to granulate in the prior art.

[0123] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A mixing and pre-granulation device, characterized in that, The device includes a rotating drum, a stirring mechanism, and a granulation mechanism. The rotating drum has a granulation chamber inside, and a feed inlet and a discharge outlet are respectively located at the top and bottom. The stirring mechanism and the granulation mechanism are installed alternately within the granulation chamber. The stirring mechanism includes a stirring shaft and a stirring paddle mounted on the stirring shaft. The granulation mechanism includes a rotating shaft and a propeller mounted on the rotating shaft. The stirring mechanism and the granulation mechanism rotate in opposite directions, and the stirring mechanism and the rotating drum also rotate in opposite directions. During rotation, the stirring paddle throws the mixed material towards the propeller, which, during rotation, granulates the mixed material. The stirring paddle includes a plurality of stirring blades, which are arranged alternately along the axial direction of the stirring shaft. The stirring blade includes a body and a receiving part. The body is mounted on the stirring shaft and extends radially toward the stirring shaft at both ends. The receiving part is obliquely fixed to the body. The granulation mechanism is vertically suspended at the top of the rotating drum and located above the discharge port.

2. The mixing and pre-granulation device according to claim 1, characterized in that, The distance between the granulation mechanism and the bottom of the rotating drum is 5mm to 15mm.

3. The mixing and pre-granulation device according to claim 1, characterized in that, There is at least one stirring mechanism and one granulation mechanism, with the stirring mechanism located around the periphery of the granulation mechanism.

4. The mixing and pre-granulation device according to claim 1, characterized in that, The rotating drum is equipped with a drum wall scraper, and the blade of the drum wall scraper is spaced apart from the inner wall of the rotating drum.

5. The mixing and pre-granulation device according to claim 4, characterized in that, The blade of the barrel wall scraper is 5mm to 10mm away from the inner wall of the rotating barrel.

6. The mixing and pre-granulation device according to claim 1, characterized in that, The bottom of the rotating drum is equipped with a discharge disc for controlling the opening of the discharge port.

7. A method for uniform pregranulation, comprising the uniform pregranulation apparatus as described in any one of claims 1-6, characterized in that, It also includes the following steps: Step S1: Preset the average particle size range and mass percentage range of the material; Step S2: Set the initial rotation speed of the granulation mechanism and the stirring mechanism; Step S3: Start the device and feed the material into the rotating drum through the feed inlet to begin mixing and pre-granulation. Step S4: Detect whether the average particle size and mass percentage of the granulated material are within a preset range. When the detected average particle size and mass percentage are within the preset range, the rotation speed of the granulation mechanism and the stirring mechanism remains unchanged. When the detected average particle size and mass percentage exceed the preset range, the rotation speeds of the granulation mechanism and the stirring mechanism are adjusted respectively.

8. The method for mixing and pre-granulating according to claim 7, characterized in that, In step S4, When the detected average particle size and mass percentage are both greater than the preset values, the rotation speed of the stirring mechanism is increased while the rotation speed of the granulation mechanism is decreased. When the detected average particle size is greater than the maximum value of the preset range and the mass percentage is within the preset range, the rotation speed of the stirring mechanism remains unchanged, and the rotation speed of the pelletizing mechanism is reduced. When the detected average particle size is greater than the maximum value of the preset range and the mass percentage is less than the minimum value of the preset range, the rotation speed of the granulation mechanism is kept constant while the rotation speed of the stirring mechanism is increased. When the detected average particle size is within the preset range and the mass percentage is greater than the maximum value of the preset range, the rotation speed of the stirring mechanism is kept constant while the rotation speed of the pelletizing mechanism is reduced. When the detected average particle size and mass percentage are both within the preset range, the rotation speed of the stirring mechanism and the granulation mechanism remains unchanged. When the detected average particle size is within the preset range and the mass percentage is less than the minimum value of the preset range, the rotation speed of the stirring mechanism is kept constant, and the rotation speed of the pelletizing mechanism is increased. When the detected average particle size is less than the minimum value of the preset range and the mass percentage is greater than the maximum value of the preset range, the rotation speed of the pelletizing mechanism is kept constant while the rotation speed of the stirring mechanism is reduced. When the detected average particle size is less than the minimum value of the preset range and the mass percentage is within the preset range, the rotation speed of the stirring mechanism remains unchanged, and the rotation speed of the granulation mechanism is increased. When the detected average particle size and mass percentage are both less than the minimum value of the preset range, the rotation speed of the granulation mechanism is increased while the rotation speed of the stirring mechanism is decreased.

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