Manufacturing methods that can change the particle size of cold-rolled pellets

Abstract

A method for manufacturing cold-pressed pellets with variable particle size includes a preparation step, a grinding step, a humidification step, and a granulation step. The preparation step involves preparing multiple fine powders as raw materials and mixing them with at least one compounding agent to form a material to be processed. The grinding step involves grinding the material to be processed using a ball mill and detecting an instantaneous humidity value of the ground material downstream of the ball mill. The humidification step involves comparing the instantaneous humidity value with a preset humidity value to generate a humidification parameter, and adding moisture to the material to be processed using a humidifier according to the humidification parameter. The granulation step involves feeding the material to be processed into a granulation pan and, after passing through multiple water-addition stages with different types of moisture introduction, forming pellets with a set particle size.

Description

Technical Field

[0001] This invention relates to a method for pelletizing recycled materials, and more particularly to a manufacturing method that can change the particle size of cold-pressed pellets. Prior Technology

[0002] Granulated ore pellets are the raw materials fed into the blast furnace. They are mainly made from fine iron and carbon powder from steel plants, mixed with a binder, and then sprayed with water to form lumps with a specific particle size. The resulting pellets must undergo curing to reach a specific strength before being sent to the next stage as blast furnace feed. Because these granulated pellets are the raw materials fed into the blast furnace and sintering process, the particle size must be carefully controlled to precisely control the smelting parameters, thereby ensuring the quality of the blast furnace smelting products and maximizing the efficiency of the sintering process.

[0003] Currently, in addition to using new binder formulations to control the particle size of the granulated ore, the subsequent addition of moisture is also quite important. Furthermore, processes using binders require further sintering to produce the desired ore pellets. With such complex process steps, it is difficult to reduce manufacturing costs. Summary of the Invention

[0004] Therefore, the object of this invention is to provide a manufacturing method that can change the particle size of cold-mixed pellets, which helps to accurately control the particle size.

[0005] Therefore, the method for manufacturing cold-granulated pellets of the present invention includes a preparation step, a grinding step, a humidification step, and a granulation step.

[0006] The preparatory step involves preparing multiple fine powders as raw materials and mixing them with at least one compounding agent to form a material to be processed.

[0007] The grinding step involves grinding the material to be processed using a ball mill and detecting an instantaneous moisture value of the material to be processed downstream of the ball mill after grinding.

[0008] The humidification step involves comparing the real-time humidity value with a preset humidity value to generate a humidification parameter, and then using a humidifier to add moisture to the material to be treated using the humidification parameter.

[0009] The granulation step involves feeding the material to be processed into a granulation pan and, after several stages of water addition with different types of water introduction, producing pellets with a set particle size.

[0010] The advantage of this invention is that after the material to be processed is ground, a preset humidity value is specifically set in the humidification step, and the humidification parameter to be adjusted is accurately provided by comparing it with the real-time humidity value. In this way, when entering the granulation step, the moisture can be accurately introduced in accordance with the different stages of the nucleation stage and the nucleus growth stage, so as to ensure that the pellets that meet the desired particle size value (i.e. the set particle size) are accurately granulated. Simple Explanation of the Diagram

[0011] Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, wherein: Figure 1 is a block diagram illustrating one embodiment of the manufacturing method of the present invention that can change the particle size of cold-rolled pellets; Figure 2 is a system configuration diagram illustrating the equipment used in this embodiment; Figure 3 is a side view illustrating a granulation disc used in one of the granulation steps of this embodiment; and Figure 4 is a schematic diagram illustrating the multiple water outlet valves used in conjunction with the granulation disc. Implementation

[0012] Referring to Figure 1, this is an embodiment of the manufacturing method of cold-rolled pellets according to the present invention, which can change the particle size of the pellets. This embodiment includes a preparatory step 11, a grinding step 12, a humidification step 13, and a granulation step 14. In this embodiment, the raw material is iron-carbon recycled powder, and water is added to produce pellets with the desired particle size.

[0013] Referring to Figures 1 and 2, this preparatory step 11 involves preparing multiple fine powder materials as raw materials and mixing them with at least one additive to form a material to be treated. The fine powder materials are obtained from a recycling system, pulverized by a blast furnace ash pulverizing system, and initially ground to a particle size of 0.5 to 150 micrometers before being weighed and batched. The additive contains early-strength cement and bentonite, which enhance the plasticity of the material to be treated and provide a certain bonding strength.

[0014] The grinding step 12 involves grinding the material to be processed using a ball mill 2, and detecting an instantaneous humidity value of the material to be processed after grinding downstream of the ball mill 2 as a reference for subsequent humidification.

[0015] The humidification step 13 involves comparing the instantaneous humidity value with a preset humidity value to generate a humidification parameter, and then using a humidifier 3 to add moisture to the material to be treated according to the humidification parameter. Specifically, if the preset humidity value is set to 6.0~6.5%, and the instantaneous humidity value obtained by on-site sampling and measurement is 3.0~3.5%, then considering a 3% error, the humidification parameter of the humidifier 3 can be set to 4%, thereby maintaining the material to be treated at the preset humidity value as much as possible.

[0016] The granulation step 14 involves feeding the material to be processed into a granulation disc 4 and, after several water addition stages with different types of water introduction, producing pellets with a set particle size. As shown in Figures 3 and 4, the granulation disc 4 includes a base 41, a rotating disc 42 disposed on the base 41 at an adjustable angle relative to the horizontal plane, and five water outlet valves 43 facing the rotating disc 42. Preferably, the set angle is 54 degrees, and the rotation speed of the rotating disc 42 is set to 42 Hz.

[0017] Referring to Figures 3 and 4 and in conjunction with Figure 1, specifically, of the five water outlet valves 43, two are responsible for granulating and nucleating the material to be processed on the rotating disk 42; while the other three are responsible for coordinating with subsequent material discharge, allowing the nuclei to continue growing and increasing the particle size. Therefore, the granulation step 14 includes two water addition stages. In the first water addition stage, two water outlet valves 43 are opened, and water is discharged in a point-like manner, allowing the material to be processed, which is still in powder form, to nucleate as quickly as possible. In the second water addition stage, three water outlet valves 43 are opened, and water is discharged in a mist-like manner, thereby enabling the nucleation in the previous stage to more efficiently adhere to the subsequent feed and form a layer under the mist-like water discharge, thereby allowing the particle size to grow until the granulated pellets reach the required particle size.

[0018] It is worth noting that the control of these water outlet valves 43, in addition to allowing the operator to manually open them by visually observing the granulation disc 4, can also be combined with an image recognition system to identify each nucleation state or the real-time particle size of the pellets being granulated to achieve automatic control, thereby further saving manpower and maximizing the implementation of automated operation. It should also be noted that, in this embodiment, the optimal moisture ratio of the granulation disc 4 is 10.7~11.3%, resulting in pellets that are less prone to sticking together, less likely to break later, and with more precise control over the particle size.

[0019] In summary, this invention can change the manufacturing method of cold-processed pellets. From grinding to nucleation and layering in granulation to expand particle size, the material to be processed can be precisely maintained under relatively appropriate humidification conditions at each stage. This not only improves granulation efficiency but also allows for precise control of the pellet size after granulation, resulting in a very high yield. Therefore, the objective of this invention is indeed achieved.

[0020] However, the above description is merely an embodiment of the present invention and should not be construed as limiting the scope of the present invention. Any simple equivalent changes and modifications made in accordance with the scope of the patent application and the contents of the patent specification shall still fall within the scope of the patent of the present invention.

[0021] 11: Preparatory Steps

[0022] 12: Grinding Steps

[0023] 13: Humidification Steps

[0024] 14: Granulation Steps

[0025] 2: Ball mill

[0026] 3: Humidifier

[0027] 4: Granulation disc

[0028] 41: Base

[0029] 42: Rotating disk section

[0030] 43: Water outlet valve

Claims

1. A method for manufacturing cold-pressed pellets capable of changing particle size, comprising: a preparatory step of preparing a plurality of fine powders as raw materials and mixing them with at least one compounding agent to form a material to be processed; a grinding step of grinding the material to be processed using a ball mill and detecting an instantaneous humidity value of the material to be processed downstream of the ball mill; a humidification step of comparing the instantaneous humidity value with a preset humidity value to generate a humidification parameter, and adding moisture to the material to be processed using a humidifier with the humidification parameter; and a granulation step of granulating the material to be processed. The material to be processed is introduced into a granulation disc, which includes a base, a rotating disk portion disposed on the base at an adjustable angle relative to a horizontal plane, and a plurality of water outlet valves facing the rotating disk portion. The granulation step includes two water addition stages. In the first water addition stage, two water outlet valves are opened to dispense water in a point-like manner. In the second water addition stage, three water outlet valves are opened to dispense water in a mist-like manner, thereby forming the material to be processed into pellets with a set particle size.

2. The manufacturing method for changing the particle size of cold-rolled pellets as described in claim 1, wherein, In this humidification step, the preset humidity value is 6.0~6.5%.

3. A manufacturing method for altering the particle size of cold-pressed pellets as described in claim 1, wherein, The set angle of the rotating part of the granulation disc is 54 degrees.

4. A manufacturing method for altering the particle size of cold-pressed pellets as described in claim 1, wherein, The rotational speed of the rotating part of the granulation disc is 42 Hz.

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