Air supply structure of raw material grinding mill
By introducing structures such as settling pipes, filter cylinders, and airflow distribution pipes into the raw material grinding mill, the problems of secondary dust generation and airflow turbulence caused by insufficient ventilation in the vertical mill system have been solved, achieving efficient grinding and energy consumption optimization.
Patent Information
- Application Number
- CN202520920370.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-12
- Publication Date
- 2026-08-25
- Estimated Expiration
- 2035-05-12
AI Technical Summary
Existing vertical mill systems suffer from problems such as insufficient ventilation during the air replenishment process, leading to secondary dust re-entrainment and disordered airflow, which affect grinding efficiency and energy consumption.
A raw material grinding mill air supply structure was designed, including a settling pipe, a filter cylinder, an airflow distribution pipe, and a conical cylinder. Through settling, filtration, and redirection of airflow paths, efficient dust settling and filtration are achieved, dust is prevented from depositing on the inner wall of the pipe, and airflow organization is optimized.
It effectively reduced the dust concentration in the vertical mill system, improved grinding efficiency, reduced operating costs, and solved the problems of insufficient ventilation and dust.
Smart Images
Figure CN224672843U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of cement production equipment technology, and in particular to a raw material grinding mill air supply structure. Background Technology
[0002] In recent years, while my country's cement industry has experienced rapid development, it has also faced the dual pressures of increasingly stringent environmental regulations and upgraded energy management. As a high-energy-consuming industry, energy conservation and emission reduction in the cement production process have become core issues for the survival and development of enterprises. Among these, the vertical mill system in the cement raw material preparation stage, due to its combined functions of grinding, drying, and powder selection, has become a key node for energy efficiency optimization. However, existing vertical mill systems generally suffer from insufficient ventilation in actual operation, directly affecting powder selection efficiency and leading to increased energy consumption. To solve this problem, the industry has attempted to introduce waste heat air from rotary kilns as a source of make-up air, but the resulting dust control deficiencies urgently require technological innovation.
[0003] The stable operation of a vertical mill system is highly dependent on a reasonable airflow organization. During the raw material grinding process, insufficient ventilation will lead to the following problems: (1) the material flowability in the grinding chamber will decrease, forming a stagnant layer and aggravating the ineffective wear of the grinding disc and grinding rollers; (2) fine particles cannot be carried into the classifier in time, resulting in a decrease in classifier efficiency and an increase in the proportion of qualified raw material returned; (3) the increased system resistance forces the main fan to operate at high load for a long time, and the power consumption per ton of raw material will increase significantly. Studies have shown that when the system ventilation is 15% lower than the design value, the classifier efficiency loss can reach 20%-30%, and the unit power consumption increases by 8%-12%.
[0004] Currently, to alleviate insufficient ventilation, the industry commonly uses the method of adding external circulation fans to introduce the high-temperature exhaust gas (200-350℃) from the rotary kiln into the vertical mill system. Although this solution can increase the ventilation volume, it has the following technical bottlenecks, including the problem of secondary dust re-entrainment: the exhaust gas from the kiln tail carries a large number of incompletely settled fine particles (<30μm), which, when directly introduced into the vertical mill, mix with the high-concentration dust in the grinding zone, causing a sharp increase in the dust concentration in the system (up to 1000g / Nm³). 3 The above-mentioned issues can also cause airflow disruption. An unreasonable coupling design between the make-up air duct and the original system's airflow path can easily lead to turbulence at the mill inlet, disrupting material stratification and ultimately reducing grinding efficiency. Therefore, there is an urgent need to develop an integrated make-up air technology for vertical mills that balances enhanced ventilation, efficient dust settling, and optimized system energy efficiency, breaking through the existing triangular contradiction of "make-up air - dust removal - energy consumption." Utility Model Content
[0005] This utility model provides a raw material grinding mill air supply structure, which solves the problems of secondary dust generation and disordered airflow caused by the traditional air supply structure of vertical mill systems.
[0006] To achieve the above objectives, this utility model provides a raw material grinding mill air supply structure, including a raw material grinding mill body. A vertical settling pipe is provided on one side of the raw material grinding mill body, and an air outlet is provided on the side wall of the settling pipe. The air outlet is connected to the air supply inlet of the raw material grinding mill body through an air supply pipe. An air inlet is provided at the top of the settling pipe, and one end of the air inlet is connected to a bend pipe joint. The other end of the bend pipe joint is connected to a fan through an air supply pipe.
[0007] As an improvement to the technical solution of this utility model, a base is provided at the lower end of the settling pipe, an inspection port is provided on the side wall of the lower end of the settling pipe, and an inspection door is provided on the inspection port.
[0008] As an improvement to the technical solution of this utility model, a filter cylinder is coaxially arranged inside the settling pipe, and two first flanges are provided at the upper and lower ends of the filter cylinder. Each first flange of the filter cylinder is fixedly connected to the inner wall of the settling pipe, and the air outlet is located between the two first flanges of the filter cylinder.
[0009] As an improvement to the technical solution of this utility model, an airflow distribution pipe is coaxially arranged inside the filter cylinder, and a second flange is provided at the upper end of the airflow distribution pipe, with the lower end face of the second flange abutting against the upper end face of the first flange.
[0010] Furthermore, a conical cylinder is provided at the lower end of the airflow distribution pipe, and the lower end of the conical cylinder is connected to the unloading pipe. Multiple positioning rods are provided between the side wall of the unloading pipe and the inner wall of the settling pipe.
[0011] Furthermore, a dispersion block is provided inside the airflow distribution pipe. The dispersion block is fixedly connected to the inner wall of the airflow distribution pipe via a connecting rod. A vertically arranged air collecting pipe is provided below the dispersion block. Multiple diversion pipes are arranged along the circumferential direction at the lower end of the air collecting pipe. The upper end of each diversion pipe is connected to the air collecting pipe, and the lower end extends through the side wall of the conical cylinder and out of the outside of the conical cylinder.
[0012] As can be seen from the above technical solutions, this utility model provides a raw material grinding mill air supply structure.
[0013] Compared with the prior art, the beneficial effects of this utility model are: This invention uses a blower to extract high-temperature gas from the tail of the rotary kiln and then sequentially transports it to the inside of the raw material grinding mill through an air supply pipe, a settling pipe, and a makeup air pipe. This process heats and dries the raw material inside the grinding mill while simultaneously supplying air to the mill. Large dust particles in the airflow can settle through the settling pipe. The inner wall of the airflow pipe is rounded and smooth, preventing dust from accumulating on the inner walls of the makeup air pipe and the air supply pipe. This solves the problem of dust affecting the vertical mill system and prevents turbulence in the airflow entering the vertical mill system. Attached Figure Description
[0014] To more clearly illustrate the technical solution of this utility model, the drawings used in the implementation examples will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.
[0015] Figure 1 This is a schematic diagram of the overall structure of the air supply structure for a raw material grinding mill proposed in this utility model; Figure 2 This is a cross-sectional schematic diagram of the internal structure of the settling pipe of the air supply structure for a raw material grinding mill proposed in this utility model; Figure 3 Appendix to this utility model Figure 2 A magnified schematic diagram of the structure at position I.
[0016] In the picture: 1-Raw material grinding mill body; 11-Make-up air inlet; 2-Settling pipe; 21-Air outlet; 22-Make-up air pipe; 23-Air inlet; 24-Bend joint; 25-Air supply pipe; 26-Base; 27-Inspection door; 3- Fan; 4-Filter cylinder; 41-First flange; 5-Airflow distribution pipe; 51-Second flange; 52-Dispersion block; 53-Connecting rod; 54-Gas collection pipe; 55-Diverter pipe; 6-Conical cylinder; 61-Discharge pipe; 62-Positioning rod. Detailed Implementation
[0017] To enable those skilled in the art to better understand the technical solutions of this utility model, the technical solutions in the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings.
[0018] Example 1: like Figures 1-3This illustration shows a raw material grinding mill air supply structure, including a raw material grinding mill body 1. A vertical settling pipe 2 is installed on the ground on one side of the raw material grinding mill body 1. The settling pipe 2 is used to settle dust in the airflow. An air outlet 21 is provided on the side wall of the settling pipe 2. The air outlet 21 is connected to the air supply inlet 11 of the raw material grinding mill body 1 through an air supply pipe 22. An air inlet 23 is provided at the top of the settling pipe 2. One end of the air inlet 23 is connected to a bend joint 24. The other end of the bend joint 24 is connected to the exhaust port of a blower 3 through an air supply pipe 25. The air supply port of the blower 3 is connected to the tail of a rotary kiln through a pipe. The kiln tail gas temperature is about 300 degrees Celsius, so the blower 3 should be a high-temperature resistant blower. The blower 3 extracts the high-temperature gas from the kiln tail of the rotary kiln and transports it to the raw material grinding mill body 1 through the air supply pipe 25, the settling pipe 2, and the make-up air pipe 22 in sequence. This heats and dries the raw material inside the raw material grinding mill body 1 and simultaneously makes up the air inside the raw material grinding mill body 1. Large dust particles in the airflow can be settled through the settling pipe 2. The inner wall of the airflow pipe is made of smooth arc transition, and the pipe bending angle and connection method are optimized so that dust will not stay on the inner wall of the make-up air pipe 22 and the air supply pipe 25 and block the pipe.
[0019] Please see Figure 1 Based on the above embodiments, in order to facilitate the removal of the dust deposited inside the settling pipe 2, an inspection port is opened on the side wall of the settling pipe 2, and an inspection door 27 is installed on the inspection port. By opening the inspection door 27, it is convenient to clean the dust deposited inside the settling pipe 2, and also convenient to maintain and repair the various components inside the settling pipe 2.
[0020] Please see Figure 2As an improved embodiment of the above example, since the dust inside the settling pipe 2 settles entirely by the large angle inflection point between the outlet 21 and the airflow transported inside the settling pipe 2, the settling effect is generally poor. It can only settle larger dust particles. For smaller dust particles, the settling effect is not good, and they will continue to enter the mill with the airflow, affecting the composition of the raw material inside the mill. In order to better settle the dust, a filter cylinder 4 is coaxially installed inside the settling pipe 2. The side wall of the filter cylinder 4 is covered with filter holes. One or more layers of high-temperature resistant dust removal filter bags are attached and fixed to the inner wall of the filter cylinder 4. The dust removal filter bags are fixed to the inner wall of the filter cylinder 4 by rivets. The dust removal filter cloth can filter the small dust particles. The filter holes facilitate the filtration of dust, so that the dust is trapped inside the settling pipe 2. Two first flanges 41 are provided at the upper and lower ends of the filter cylinder 4. The diameter of the two first flanges 41 is the same as the inner diameter of the settling pipe 2. Each first flange 41 of the filter cylinder 4 is connected to the inner wall of the settling pipe 2. The inner wall of the settling pipe 2 is fixedly connected by screws. Specifically, the screws are inserted into the screw holes on the outer side wall of the settling pipe 2 and threadedly connected to the threaded holes on the side wall of the first flange 41, thus fixing the two first flanges 41 on the filter cylinder 4 to the inner wall of the settling pipe 2. The air outlet 21 is located between the two first flanges 41 of the filter cylinder 4, so that the airflow in the settling pipe 2 must pass through the filter holes of the filter cylinder 4 before it can be discharged from the air outlet 21. The dust can be filtered through the filter holes on the side wall of the filter cylinder 4, causing the dust to fall back to the bottom of the settling pipe 2. Compared with natural sedimentation to collect dust, the method of using the filter cylinder 4 to filter and collect dust is more effective. In addition, the staff needs to regularly use a sledgehammer to knock on the side wall of the settling pipe 2 to clean the dust adsorbed on the filter cylinder 4 that is fixedly connected to it. Furthermore, the staff needs to regularly open the maintenance door 27 to enter the settling pipe 2 and knock on the filter cylinder 4 to clean the stubborn dust in the filter bag pores, preventing the filter cylinder 4 from losing its filtering effect after long-term use.
[0021] Please see Figure 2 An airflow distribution pipe 5 is coaxially arranged inside the filter cylinder 4. A second flange 51 is fixedly installed at the upper end of the airflow distribution pipe 5. The lower end face of the second flange 51 abuts against the upper end face of the first flange 41. The outer diameter of the airflow distribution pipe 5 is smaller than the inner diameter of the filter cylinder 4. A gap is reserved between the airflow distribution pipe 5 and the inner wall of the filter cylinder 4. By sealing the upper end of the filter cylinder 4 through the second flange 51, the airflow direction is changed, so that the airflow first enters the interior of the airflow distribution pipe 5 from top to bottom, then flows along the airflow distribution pipe 5 and is discharged from the lower end of the airflow distribution pipe 5. Then it rises along the gap between the airflow distribution pipe 5 and the filter cylinder 4, passes through the filter holes of the filter cylinder 4, and is discharged from the air outlet 21. By changing the airflow direction at a large angle, large particles in the dust settle faster and are prevented from continuing to be transported with the airflow.
[0022] Please see Figure 2 , 3 A conical cylinder 6 is provided at the lower end of the airflow distribution pipe 5. The lower end of the conical cylinder 6 is connected to the unloading pipe 61. Two positioning rods 62 are provided between the side wall of the unloading pipe 61 and the inner wall of the settling pipe 2. The unloading pipe 61 can be suspended and fixed on the inner wall of the settling pipe 2 by the two positioning rods 62. The dust in the airflow distribution pipe 5 can be collected by the conical cylinder 6 and discharged into the bottom of the settling pipe 2 through the unloading pipe 61.
[0023] Please see Figure 2 , 3 A dispersion block 52 is coaxially arranged inside the airflow distribution pipe 5. The dispersion block 52 is a conical shell. The side wall of the dispersion block 52 is fixedly connected to the inner wall of the airflow distribution pipe 5 by two connecting rods 53. A vertically arranged air collecting pipe 54 is arranged below the dispersion block 52. The upper part of the air collecting pipe 54 extends upward into the interior of the dispersion block 52. Three diversion pipes 55 are arranged circumferentially at the lower end of the air collecting pipe 54. The upper end of each diversion pipe 55 is sealed and connected to the air collecting pipe 54. The lower end of the diversion pipe 55 penetrates the side wall of the conical cylinder 6. The mounting hole extends downwards at an angle outside the conical cylinder 6. The airflow is first dispersed by the dispersion block 52, then enters the interior of the dispersion block 52 from the bottom, and enters the interior of the air collection pipe 54 from the top. It then exits from the three diversion pipes 55, rises along the gap between the airflow distribution pipe 5 and the filter cylinder 4, and exits from the air outlet 21 through the filter holes on the side wall of the filter cylinder 4. The particulate dust can settle by being redirected at a large angle by the dispersion block 52 and the air collection pipe 54.
[0024] As can be seen from the above technical solutions, when using them, please refer to... Figure 2 , 3The air supply port of blower 3 is connected to the kiln tail of the rotary kiln through a long-distance pipeline. Blower 3 is started, and the high-temperature gas from the kiln tail is extracted by blower 3 and transported to the raw material grinding mill body 1 through air supply pipe 25, settling pipe 2, and make-up air pipe 22 in sequence. The raw material inside the raw material grinding mill body 1 is heated and dried, and air is made up inside the raw material grinding mill body 1 at the same time. Large dust particles in the airflow can be settled through settling pipe 2. In settling pipe 2, the airflow is transported from top to bottom. When it descends to the dispersion block 52, the airflow is dispersed by the conical structure of the dispersion block 52. Then, the airflow is concentrated and collected through the air collecting pipe 54. Larger dust particles will collide with the conical cylinder under the redirection of this structure. The inner wall of the cone-shaped cylinder 6 reduces its moving speed. Under the action of gravity, the gas is discharged into the discharge pipe 61 through the discharge pipe 6. The gas gathered by the gas collecting pipe 54 is dispersed and sprayed onto the lower inner wall of the settling pipe 2 through the diverter pipe 55. Then it is immediately conveyed upward through the filter holes on the side wall of the filter cylinder 4. The dust is further filtered through the filter holes. The filtered air is discharged through the air outlet 21 and conveyed to the raw material grinding mill body 1 through the air supply pipe 22. The raw material inside the raw material grinding mill body 1 is heated and dried, and air is supplied to the raw material grinding mill body 1 at the same time. Large dust particles in the airflow can be settled through the settling pipe 2. The concentration of particulate matter in the gas entering the vertical mill can be reduced to 10-30 mg / m³. 3 The operating cost of the vertical mill is reduced by 20%.
[0025] Other embodiments of the present invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. The present invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope of the invention is indicated by the claims.
[0026] It should be understood that this utility model is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The embodiments of this utility model described above do not constitute a limitation on the scope of protection of this utility model.
Claims
1. A raw material grinding mill air supply structure, comprising a raw material grinding mill body (1), characterized in that: A vertical settling pipe (2) is provided on one side of the raw material grinding mill body (1). An air outlet (21) is provided on the side wall of the settling pipe (2). The air outlet (21) is connected to the air inlet (11) of the raw material grinding mill body (1) through the air supply pipe (22). An air inlet (23) is provided at the top of the settling pipe (2). One end of the air inlet (23) is connected to a bend pipe joint (24). The other end of the bend pipe joint (24) is connected to the blower (3) through the air supply pipe (25).
2. The air supply structure for a raw material grinding mill according to claim 1, characterized in that, The lower end of the settling pipe (2) is provided with a base (26), and an inspection port is provided on the lower side wall of the settling pipe (2), and an inspection door (27) is provided on the inspection port.
3. The air supply structure for a raw material grinding mill according to claim 2, characterized in that, A filter cylinder (4) is coaxially arranged inside the settling pipe (2). Two first flanges (41) are provided at the upper and lower ends of the filter cylinder (4). Each first flange (41) of the filter cylinder (4) is fixedly connected to the inner wall of the settling pipe (2). The air outlet (21) is located between the two first flanges (41) of the filter cylinder (4).
4. The air supply structure for a raw material grinding mill according to claim 3, characterized in that, An airflow distribution pipe (5) is coaxially arranged inside the filter cylinder (4). A second flange (51) is provided at the upper end of the airflow distribution pipe (5). The lower end face of the second flange (51) abuts against the upper end face of the first flange (41).
5. The air supply structure for a raw material grinding mill according to claim 4, characterized in that, The lower end of the airflow distribution pipe (5) is provided with a conical cylinder (6), the lower end of the conical cylinder (6) is connected to the unloading pipe (61), and multiple positioning rods (62) are provided between the side wall of the unloading pipe (61) and the inner wall of the settling pipe (2).
6. The air supply structure for a raw material grinding mill according to claim 5, characterized in that, A dispersion block (52) is provided inside the airflow distribution pipe (5). The dispersion block (52) is fixedly connected to the inner wall of the airflow distribution pipe (5) via a connecting rod (53). A vertically arranged air collecting pipe (54) is provided below the dispersion block (52). Multiple diversion pipes (55) are arranged along the circumferential direction at the lower end of the air collecting pipe (54). The upper end of each diversion pipe (55) is connected to the air collecting pipe (54), and the lower end extends through the side wall of the conical cylinder (6) and out of the outside of the conical cylinder (6).