Air volume intelligent control system and method for efficient intelligent pneumatic mixing equipment

Abstract

The invention relates to the field of cement production equipment, in particular to an air volume intelligent control system and method for efficient intelligent pneumatic mixing equipment. The control system comprises a CaO content online analyzer which is integrated at the front section of a feeding point of a warehousing bucket elevator and is used for detecting the CaO content in a cement finished product in real time; the control unit is in communication connection with the sensing unit and is configured to calculate the total air volume requirement in real time based on the following parameters: real-time warehousing bucket lifting current I; the CaO content Wt is measured in real time; presetting a reference current I0, a CaO target value Wset, a current adjusting coefficient KI and a CaO content adjusting coefficient Kw; the air supply unit is controlled by the control unit and inputs mixing high-pressure air flow into the cavity of the multi-chamber mixing box, and the operation frequency and the air flow of the fan can be adjusted according to the total air volume requirement. The cement mixing device is used for the mixing procedure of all component cement finished products in the cement production process, efficient mixing of all component cement under different working conditions is guaranteed, and the use amount of clinker in cement is further reduced.

Description

Technical Field

[0001] The present invention relates to the field of cement production equipment, and in particular to an intelligent air volume control system and method for high-efficiency intelligent pneumatic mixing equipment. Background Art

[0002] At present, the cement mixing equipment commonly used in industry is divided into three types: mechanical, pneumatic, and mechanical-pneumatic combined. Among them, mechanical mixing equipment uses a stirring shaft and blades to stir and mix the materials in the mixing box. The equipment studio only mixes the materials in the area around the stirring shaft and blades. There is a mixing dead zone in the box, the space utilization rate is low, and the blades are severely worn, making maintenance difficult. Pneumatic mixing equipment uses a high-pressure fan to inflate the mixing box. The materials move disorderly in a fluidized state in the box to achieve the purpose of mixing. When used, there is often a problem of low gas energy utilization. Mechanical-pneumatic composite mixing equipment achieves sufficient and uniform mixing of materials through the dual effects of the fluidization of the inflation box and the stirring blades. The movement and dispersion of the materials during the mixing process are more complicated, and there may be problems of excessive energy consumption and difficulty in controlling the mixing effect.

[0003] In summary, the problems existing in the prior art are:

[0004] (1) The mixing accuracy is limited and there is a lack of adjustable means;

[0005] (2) Low gas energy utilization rate and high energy consumption;

[0006] (3) Equipment reliability and intelligent control level are low. Summary of the Invention

[0007] In response to the shortcomings of the existing technology, the present invention provides an intelligent air volume control system and method for high-efficiency intelligent pneumatic mixing equipment, which is used in the mixing process of the finished cement products of various components in the cement production process, ensuring the efficient mixing of the various components of cement under different working conditions, improving the quality stability of cement products, further reducing the amount of clinker in cement, and reducing carbon emissions in the cement production process.

[0008] One of the purposes of the present invention is to provide an intelligent air volume control system for an efficient and intelligent pneumatic mixing device, wherein the mixing device comprises a multi-chamber mixing box, the bottom of which is provided with a breathable layer and an air filling box;

[0009] The sensing unit includes an online CaO content analyzer integrated in front of the hopper feeding point for real-time detection of CaO content in finished cement products;

[0010] A control unit is in communication with the sensor unit and is configured to calculate the total air volume demand in real time based on the following parameters:

[0011] Real-time storage bucket lifting current I;

[0012] Real-time CaO content W t ;

[0013] Preset reference current I0, CaO target value W set , current adjustment coefficient K1 and CaO content adjustment coefficient K W ;

[0014] The air supply unit is controlled by the control unit and inputs mixed high-pressure airflow into the chamber of the multi-chamber mixing box. The fan operating frequency and air volume can be adjusted according to the total air volume demand.

[0015] Furthermore, the control unit calculates the total air volume requirement using the following formula:

[0016]

[0017] Among them, Q base As the basic air volume, through the formula Q base =60·ν·b·L, where ν is the air consumption per unit area, b is the width of the breathable layer, and L is the length of the breathable layer;

[0018] K I : Storage current adjustment coefficient; K W : CaO content adjustment coefficient; I: real-time storage bucket lifting current, A; I0 is the reference current; W t : Real-time CaO content, %; W set is the CaO target value; I max , I min are the maximum / minimum thresholds of the incoming current; W max 、W min : The maximum / minimum thresholds of CaO content respectively.

[0019] Furthermore, the air supply unit includes an air supply duct, an air volume regulating valve is provided on the air supply duct, and a high-pressure convection cap is provided at the end of the air supply duct; the high-pressure fan provides high-pressure gas which is evenly fed into the inflation box through the air supply duct and the high-pressure convection cap.

[0020] Furthermore, the air supply duct is arranged at the bottom of the multi-chamber mixing box and provides vertical upward wind force to each chamber. The air volume at the feed end of each chamber is smaller than that at the discharge end. Under the action of the height difference of the boiling material surface at the feed and discharge ends, the material is continuously transferred from the high material surface to the low material surface, and a strong vortex motion is formed in a single chamber; the air volume difference from the first chamber to the last chamber decreases step by step to construct a turbulence gradient that decays step by step.

[0021] Furthermore, it also includes an adjustable flow valve assembly with adjustable opening arranged in the multi-chamber mixing box, which is used to separate adjacent chambers; the adjustable flow valve assembly includes a matching drive motor and reducer arranged on the outside of the multi-chamber mixing box, and the drive motor is connected to the control unit signal; the reducer is connected to one end of the flow valve plate, the main body of the flow valve plate is located in the multi-chamber mixing box, and the plate body can move up and down along the valve plate track under the drive of the drive motor and the reducer to adjust the opening.

[0022] The present invention also discloses a control method for the air volume intelligent control system for the efficient intelligent pneumatic mixing equipment, comprising the following steps:

[0023] S1. Obtain real-time CaO content of finished cement by online CaO content analyzer;

[0024] S2. Collect real-time storage bucket current I and real-time CaO content W t , combined with the preset reference current I0 and CaO target value W set , current threshold (I max , I min ) and CaO content threshold (W max 、W min ), calculate the total air volume demand Q total ;

[0025] S3. According to the total air volume demand Q total , adjust the operating frequency of the high-pressure fan and the opening of the adjustable flow valve assembly to control the boiling intensity and vortex movement of the material in the mixing equipment.

[0026] Furthermore, the calculation formula for the total air volume requirement in step S2 is:

[0027]

[0028] Among them, Q base As the basic air volume, through the formula Q base =60·ν·b·L, where ν is the air consumption per unit area, b is the width of the breathable layer, and L is the length of the breathable layer;

[0029] K I : Storage current adjustment coefficient; K W : CaO content adjustment coefficient; I: real-time storage bucket lifting current, A; I0 is the reference current; W t : Real-time CaO content, %; W set is the CaO target value; I max , I min are the maximum / minimum thresholds of the incoming current; W max 、W min : The maximum / minimum thresholds of CaO content respectively.

[0030] The present invention has the following advantages and beneficial effects:

[0031] (1) The homogenization effect is precise and controllable: The invention uses high-pressure gas as the mixing power. The materials to be mixed are in a state of fluidization and strong vortex superposition in the multi-chamber mixing box, and pass through each mixing chamber in turn in an S-shaped path, thereby maximizing the residence time in a limited space and fully mixing the materials.

[0032] The gas flow rate on the feed side of each mixing chamber is lower than that on the discharge side. Under the action of the flow velocity difference, the materials in each chamber perform a strong eddy-like circular motion, which further increases the intensity of the disordered motion of the materials and greatly improves the mixing efficiency. Moreover, the flow velocity difference of each chamber gradually decreases from the feed port to the discharge port. This is consistent with the process requirements that in the early stage of mixing, the material uniformity is poor and high-intensity eddy motion is required to achieve the fusion of the components. In the later stage of mixing, the material uniformity is high and it is necessary to improve fine mixing and avoid excessive disturbance, thereby realizing efficient utilization of the mixing space and high-pressure gas.

[0033] The adjustable flow valve assembly between the first and second chambers can control the material residence time, and the mixing accuracy can be flexibly adjusted; the radar level meter is used to feedback the current mixing intensity and control the automatic adjustment of the high-pressure fan, effectively responding to the needs of product switching and differentiation of product processing capabilities during the cement production process.

[0034] (2) The air volume can be intelligently controlled during operation, with a high level of automation: by real-time monitoring of the cement hopper current and the CaO content of the finished cement product, the air volume of the high-pressure fan can be intelligently closed-loop controlled to achieve precise control of the mixing effect during the operation, thereby avoiding fluctuations in the quality of the finished cement product caused by changes in material throughput and fluctuations in the properties of the raw materials, improving the degree of equipment automation control, and improving the stability of the quality of cement products.

[0035] (3) Lowering Cement Temperature: During cement production, the temperature of cement rises due to chemical reactions and mechanical friction. This temperature increase not only affects the storage stability of cement but also its performance. With the present invention, high-flow, high-pressure gas at room temperature fully contacts the cement, effectively lowering the temperature of the finished cement product, facilitating cement storage and improving cement performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic structural diagram of the efficient and intelligent pneumatic mixing equipment of the present invention;

[0037] Figure 2 for Figure 1 Side view of

[0038] Figure 3 This is a working principle diagram of the efficient and intelligent pneumatic mixing equipment of the present invention;

[0039] Figure 4 This is the process flow chart of pneumatic mixing.

[0040] In the figure: 1. Feed inlet; 2. Discharge outlet; 3. Multi-chamber mixing box; 4. Anti-impact device; 5. Air supply system; 5-1. High-pressure fan; 5-2. Air supply duct; 5-3. Air volume regulating valve; 5-4. Inflatable box; 5-5. High-pressure convection cap; 6. Adjustable flow valve plate; 6-1. Drive motor; 6-2. Reducer; 6-3. Flow valve plate; 6-4. Valve plate track; 7. Overflow weir; 8. Cleaning valve; 9. Radar level meter; 10. Dust collection port; 11. Inspection port; 12. Breathable layer; 13. High-efficiency intelligent pneumatic mixing equipment; 14. Feed air chute; 15. CaO online detection equipment; 16. Storage bucket elevator; 17. Finished product chute; 18. Bag dust collector; 19. Dust collection high-pressure fan; 20. Hammer unloading valve; 21. Chute high-pressure fan. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0042] like Figures 1 to 4 As shown, this embodiment discloses a high-efficiency intelligent pneumatic mixing equipment, including a multi-chamber mixing box, an anti-collision device 4 is provided inside the mixing box near the feed port 1, which can adjust the movement direction of the material entering the mixing box 3, reduce the material flow rate, and effectively reduce the collision phenomenon of the material under the action of inertia, so that the material can enter the multi-chamber mixing box 3 evenly and stably, and effectively ensure the mixing effect; preferably, the anti-collision device 4 adopts a stepped baffle, and adjacent steps form a 90-degree storage area. The new feed directly contacts the material in the storage area, effectively reducing the wear of the material on the baffle during operation and improving the service life of spare parts.

[0043] The multi-chamber mixing box 3 is divided into three interconnected chambers by a material partition assembly. In this embodiment, the material partition assembly includes an adjustable flow valve assembly 6 and an overflow weir assembly 7. An adjustable flow valve assembly 6 is provided between the first and second chambers of the multi-chamber mixing box, the top of which is fixed to the box body, and a material channel with controllable opening is provided at the bottom. An overflow weir assembly 7 is provided between the second and third chambers, the bottom of which is fixed to the box body, and an overflow channel is reserved at the top. The material entering the multi-chamber mixing box flows through each chamber in turn along an S-shaped path driven by pressure. The flow rate and the dynamic liquid level difference formed by the overflow of the weir are precisely controlled by the flow valve, thereby ensuring the material residence time to the greatest extent within the limited space and achieving efficient mixing under space-constrained conditions.

[0044] Specifically, the adjustable flow valve plate 6 includes a drive motor 6-1, a reducer 6-2, a flow valve plate 6-3 and a valve plate track 6-4; the matching drive motor 6-1 and reducer 6-2 are arranged on the outside of the multi-chamber mixing box 3 and the reducer 6-2 is connected to one end of the flow valve plate 6-3, the main body of the flow valve plate 6-3 is located in the multi-chamber mixing box 3, and the plate body can move up and down along the valve plate track 6-4 under the drive of the drive motor 6-1 and the reducer 6-2 to adjust the opening.

[0045] The overflow weir assembly 7 is provided with a cleaning valve 8 located in two chambers for clearing the material accumulated on the weir body;

[0046] The bottom of the multi-chamber mixing box is equipped with a breathable layer 12, an aeration box 5-4, and an air supply duct 5-2. The air supply duct is equipped with an air volume control valve 5-3, and the end of the air supply duct 5-2 is installed with a high-pressure convection cap 5-5. High-pressure blower 5-1 provides high-pressure gas, which is evenly fed into the aeration box through the air supply duct 5-2 and high-pressure convection cap 5-5. The high-pressure gas passes through the breathable layer and comes into contact with the materials. Under the action of the high-pressure gas, the materials in the multi-chamber mixing box undergo a "micro-boiling" fluidization motion. The various components of the materials to be mixed are dispersed and integrated in this "micro-boiling" state, achieving the goal of uniform mixing of the materials.

[0047] Two air supply ducts 5-2 are provided at the bottom of each chamber of the multi-chamber mixing box; in the present embodiment, there are a total of 6 air supply ducts 5-2, and the air flow rates of the air supply ducts 5-2 from the feed end to the discharge end are V1, V2, V3, V4, V5 and V6 respectively; the flow rates of the two air sources in each chamber are differentiated by the control of the air volume regulating valve, that is, V1 < V2, V3 < V4, V5 < V6, so that the two air sources in each chamber are one strong and one weak, forming inconsistent material surfaces, and the material performs a strong counterclockwise eddy motion during the transfer from the high material surface to the low material surface in each chamber, so that the various component materials in the local range flow in different directions, which is not only conducive to quickly improving the uniformity of cement mixing, but also convenient for moving to the next chamber.

[0048] At the same time, the high-pressure gas flow rate difference between the first, second, and third chambers decreases in sequence. The first chamber has the largest flow rate difference (Δ1 = V2 - V1), the second chamber has the second largest (Δ2 = V4 - V3), and the third chamber has the smallest (Δ3 = V6 - V5), creating a step-by-step attenuation turbulence gradient. The eddy motion of the material is strongest in the first chamber, where the components are in the initial stages of mixing and the material level is higher than in the other two chambers. The large-scale, high-intensity, disordered motion at this stage can more effectively and rapidly improve the uniformity of material mixing and break up component agglomerations. As material uniformity improves, the high-pressure gas flow rate difference in the rear chamber gradually decreases, the turbulent energy level weakens chamber by chamber, the eddy motion intensity decreases, and the relative displacement between materials decreases, avoiding excessive disturbance that could cause separation of the mixed materials and facilitating localized fine mixing of the materials. Under the superimposed motion state of the above-mentioned fluidized motion state and strong vortex motion, rapid mixing of multiple coarse materials in a limited space can be achieved. At the same time, when the cement types are switched in the actual working process, the types, proportions, material throughput and product uniformity indicators of each component cement will change. Due to the large differences in mixing working conditions, the high-efficiency intelligent pneumatic mixing equipment can accurately control the mixing effect by adjusting the adjustable flow valve plate assembly and the air volume regulating valve. The specific control method is as follows: Mixing effect control: The opening of the adjustable flow valve assembly 6 is reduced, the operating frequency of the high-pressure fan connected to the air supply duct 5-2 is increased, the material pass path is extended, the residence time in the multi-chamber mixing box is increased, the high-pressure gas air volume is increased, the disordered movement of the material in the multi-chamber mixing box is enhanced, and the mixing uniformity is improved.

[0049] In addition, a dust collecting port 10 is provided on the top of the multi-chamber mixing box, and a plurality of inspection ports 11 are provided on the top and front and rear sides of the box body.

[0050] The present invention also discloses an intelligent air volume control system:

[0051] The sensor unit includes a radar level meter 9 mounted on the top of the multi-chamber mixing box to monitor the boiling state of the material surface in real time and provide feedback on the current operating status of the mixer. The radar level meter 9 should be positioned away from the feed inlet, dust collection hole, and valve plate motor, while also allowing for easy access to the top for repair and maintenance.

[0052] CaO content online analyzer: integrated in the front end of the storage bucket feeding point; during the operation of the system, the CaO content of the finished cement product is monitored in real time through the online detection equipment of CaO in the finished cement product. t .

[0053] A control unit is in communication with the sensor unit and is configured to calculate the total air volume demand in real time based on the following parameters:

[0054] Real-time storage bucket lifting current I;

[0055] Real-time CaO content W t ;

[0056] Preset reference current I0, CaO target value W set , current regulation coefficient K I And CaO content adjustment coefficient K W ;

[0057] The control unit is based on the current operating conditions of the system (the current of the hopper and the CaO content of the finished product W t ), calculate the total air volume demand in real time and automatically adjust the fan frequency to the current required air volume. The specific formula is as follows:

[0058]

[0059] Where:

[0060] Q total :Total air volume requirement (m 3 / h), which needs to be converted into operating frequency according to the characteristics of the high-pressure fan;

[0061] Q base :Basic air volume (m 3 / h);

[0062] Q base =60·ν·b·L (Formula 2)

[0063] In formula 2: ν: gas consumption per unit area, m 3 / m 2 min, ranging from 0.5 to 3.5 according to the density of the material; b: width of the breathable layer, m; L: length of the breathable layer, m.

[0064] K I : Incoming current adjustment coefficient, ranging from 0.1 to 0.6;

[0065] K W : CaO content adjustment coefficient, take 0.1~0.8;

[0066] I: Real-time bucket lifting current (A), I0 is the reference current;

[0067] W t : Real-time CaO content (%), W set is the CaO target value, which is the median of the qualified range;

[0068] I max , I min They are the maximum / minimum thresholds of the incoming current respectively;

[0069] W max 、W min : The maximum / minimum thresholds of CaO content respectively.

[0070] In the above formula, the air volume intelligent control system can be adjusted according to the incoming bucket current I and the finished product CaO content W. t Automatically adjust the high-pressure fan operating frequency to the current air volume in real time to ensure that the mixing accuracy meets the requirements while taking into account the energy consumption of the equipment.

[0071] In formula 1, the increase in the current of the bucket elevator is I, which means that the material throughput is increasing and the total air volume demand is Q. total Increase to ensure the mixing accuracy; on the contrary, the current of the hopper becomes smaller, indicating that the material throughput is reduced, and the total air volume demand Q total The greater the difference between the CaO content and the target value, the more the air volume needs to be increased.

[0072] The air supply unit is controlled by the control unit and inputs a high-pressure mixed airflow into the chambers of the multi-chamber mixing box. The fan operating frequency and airflow volume can be adjusted according to the total air volume demand. The air supply unit includes the air supply duct, air volume control valve, and high-pressure convection cap, which will not be detailed here.

[0073] Through the above control strategy, the automatic adjustment of the air volume of the high-pressure fan of the pneumatic mixing equipment is utilized to achieve intelligent automatic correction of the mixing accuracy, avoiding fluctuations in the quality of the cement finished product caused by changes in material throughput and fluctuations in the properties of cement components. The equipment reliability and system automation control level are relatively high.

[0074] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention may be made to the technical solutions described in the aforementioned embodiments, or to some or all of the technical features thereof. Such modifications or substitutions do not deviate from the essence of the corresponding technical solutions within the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An intelligent air volume control system for a high-efficiency intelligent pneumatic mixing device, the mixing device comprising a multi-chamber mixing box, the bottom of which is provided with a breathable layer and an air filling box; characterized in that: include The sensing unit includes an online CaO content analyzer integrated in front of the hopper feeding point for real-time detection of CaO content in finished cement products; A control unit is in communication with the sensor unit and is configured to calculate the total air volume demand in real time based on the following parameters: Real-time storage bucket lifting current I; Real-time CaO content W t ; Preset reference current I0, CaO target value W set , current regulation coefficient K I And CaO content adjustment coefficient K W ; The air supply unit is controlled by the control unit and inputs mixed high-pressure airflow into the chamber of the multi-chamber mixing box. The fan operating frequency and air volume can be adjusted according to the total air volume demand.

2. The air volume intelligent control system for high-efficiency intelligent pneumatic mixing equipment according to claim 1, characterized in that: The control unit calculates the total air volume requirement using the following formula: Among them, Q base As the basic air volume, through the formula Q base =60·ν·b·L, where ν is the air consumption per unit area, b is the width of the breathable layer, and L is the length of the breathable layer; K I : Storage current adjustment coefficient; K W : CaO content adjustment coefficient; I: real-time storage bucket lifting current, A; I0 is the reference current; W t : Real-time CaO content, %; W set is the CaO target value; I max , I min are the maximum / minimum thresholds of the incoming current; W max 、W min : The maximum / minimum thresholds of CaO content respectively.

3. The air volume intelligent control system for efficient and intelligent pneumatic mixing equipment according to claim 1 is characterized in that: The air supply unit includes an air supply duct, an air volume regulating valve is provided on the air supply duct, and a high-pressure convection cap is provided at the end of the air supply duct; the high-pressure fan provides high-pressure gas which is evenly fed into the inflation box through the air supply duct and the high-pressure convection cap.

4. The air volume intelligent control system for efficient and intelligent pneumatic mixing equipment according to claim 3 is characterized in that: The air supply duct is arranged at the bottom of the multi-chamber mixing box and provides vertical upward wind force to each chamber. The air volume at the feed end of each chamber is smaller than that at the discharge end. Under the action of the height difference of the boiling material surface at the feed and discharge ends, the material is continuously transferred from the high material surface to the low material surface, and a strong vortex motion is formed in a single chamber; the air volume difference from the first chamber to the last chamber decreases step by step to construct a turbulence gradient that decays step by step.

5. The air volume intelligent control system for efficient and intelligent pneumatic mixing equipment according to claim 1 is characterized in that: It also includes an adjustable flow valve assembly with adjustable opening located in the multi-chamber mixing box, which is used to separate adjacent chambers; the adjustable flow valve assembly includes a matching drive motor and reducer located outside the multi-chamber mixing box, and the drive motor is connected to the control unit signal; the reducer is connected to one end of the flow valve plate, the main body of the flow valve plate is located in the multi-chamber mixing box, and the plate body can move up and down along the valve plate track under the drive of the drive motor and the reducer to adjust the opening.

6. A control method for an air volume intelligent control system for a high-efficiency intelligent pneumatic mixing device according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1. Obtain real-time CaO content of finished cement by online CaO content analyzer; S2. Collect real-time storage bucket current I and real-time CaO content W t , combined with the preset reference current I0 and CaO target value W set , current threshold (I max , I min ) and CaO content threshold (W max 、W min ), calculate the total air volume demand Q total ; S3. According to the total air volume demand Q total , adjust the operating frequency of the high-pressure fan and the opening of the adjustable flow valve assembly to control the boiling intensity and vortex movement of the material in the mixing equipment.

7. The control method for the air volume intelligent control system of the high-efficiency intelligent pneumatic mixing equipment according to claim 6, characterized in that: The calculation formula for the total air volume requirement in step S2 is: Among them, Q base As the basic air volume, through the formula Q base =60·ν·b·L, where ν is the air consumption per unit area, b is the width of the breathable layer, and L is the length of the breathable layer; K I : Storage current adjustment coefficient; K W : CaO content adjustment coefficient; I: real-time storage bucket lifting current, A; I0 is the reference current; W t : Real-time CaO content, %; W set is the CaO target value; I max , I min are the maximum / minimum thresholds of the incoming current; W max 、W min : The maximum / minimum thresholds of CaO content respectively.

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