A process optimization method combining wet mixing and rotary drum devolatilization

Abstract

The present invention relates to a process optimization method combining wet mixing and rotary drum devolatilization, aiming to improve production efficiency, energy saving effect and solvent recovery rate. The method introduces an intelligent control system and a self-adaptive PID control algorithm to adjust the temperature, humidity, air flow rate and other parameters in real time during the wet mixing and rotary drum devolatilization process, achieving optimal control of the process. Multiple independent temperature control sections are provided in the rotary drum to gradually heat the material and optimize the solvent evaporation efficiency. A rotating booster and airflow enhancement device are also configured to improve the flowability of the material and the airflow distribution, further accelerating solvent evaporation. The solvent recovery system recovers the solvent in the exhaust gas through a condensing device, filters it and re-enters the wet mixing process. In addition, the waste heat recovery system recovers the waste heat in the exhaust gas through a heat exchanger, reducing the consumption of external energy. The invention can significantly improve solvent evaporation efficiency, reduce energy consumption, and effectively recover solvent, reducing environmental pollution.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of material processing and heat treatment, and particularly relates to a process optimization method combining wet mixing and rotary drum devolatilization. BACKGROUND

[0002] Wet mixing and rotary drum devolatilization are common processing techniques in many industrial production processes. Wet mixing uniformly disperses materials in a wet state through the mixing of solvents or water, and is suitable for the production of high polymer materials and synthetic chemicals. However, there are usually problems in the volatilization speed and humidity control of solvents in the wet mixing process, resulting in low devolatilization efficiency, high energy consumption, and large material loss. Rotary drum devolatilization, as a common dehydration and devolatilization equipment, can improve the volatilization efficiency to some extent, but the problems of uneven temperature control, unreasonable air flow distribution, and poor material flowability of the traditional rotary drum still hinder the optimization of the process.

[0003] In the prior art, the solvent volatilization efficiency after wet mixing is low, and the heating and air flow control of the rotary drum often result in energy waste and process instability. Therefore, how to improve the overall efficiency of wet mixing and rotary drum devolatilization has become a technical problem to be solved. SUMMARY

[0004] The present application relates to a process optimization method combining wet mixing and rotary drum devolatilization, aiming to improve the production efficiency, energy saving effect, and solvent recovery rate in the wet mixing and rotary drum devolatilization process. By combining an intelligent control system, precise temperature control, a rotary booster, an air flow enhancement device, and solvent recovery technology, the present application provides an optimized process, solves the problems of uneven temperature distribution, low solvent volatilization efficiency, energy waste, and environmental pollution in the prior art, thereby significantly improving the process efficiency, reducing energy consumption, and improving the solvent recovery rate.

[0005] To achieve the above objectives, the technical solution of the present application optimizes the existing process through the following key technical means:

[0006] Introduction of an intelligent control system: The present application adopts a self-adaptive PID control algorithm, and the intelligent control system can automatically adjust the process parameters according to the real-time data (humidity, temperature, and air flow rate of the materials) in the wet mixing and rotary drum devolatilization process, ensuring the optimal working state of each process link, reducing manual intervention, and improving the automation and stability of production.

[0007] Design of temperature control sections in the rotary drum: To optimize the solvent evaporation effect, the present application sets multiple independent temperature control sections in the rotary drum. The temperature of each temperature control section is adjusted step by step according to the evaporation requirements of the material, ensuring that the material is uniformly heated in the rotary drum, avoiding the problems of energy waste and low solvent evaporation efficiency caused by uneven temperature.

[0008] Rotary booster and airflow enhancement device: The present application installs a spiral rotary booster in the rotary drum to enhance the flowability of the material and increase the contact area between the material and the heated air, effectively accelerating the evaporation rate of the solvent. In addition, the airflow distribution in the rotary drum is optimized by setting a pressurized fan and an air duct adjusting device, further improving the efficiency of solvent evaporation.

[0009] Solvent recovery system: The present application configures a solvent recovery system, which recovers solvent from waste gas through a condenser and removes impurities through a precise filtration system, ensuring that the recovered solvent can be efficiently and cleanly returned to the wet mixing process, improving resource utilization and effectively reducing environmental pollution.

[0010] Waste heat recovery system: The present application also designs a waste heat recovery system, which recovers waste heat from the exhaust gas in the rotary drum through a heat exchanger, and uses the recovered heat for preheating of the material or solvent in the wet mixing process, reducing the consumption of external energy and further improving energy use efficiency.

[0011] Adjustment function based on material characteristics: The intelligent control system of the present application also has an adjustment function based on material characteristics, which can automatically adjust the heating power, airflow rate and material flowability of the rotary drum in real time according to the humidity, temperature and volatility parameters of the material, to ensure the optimal effect of the devolatilization process.

[0012] Through the application of the above technical means, the present application effectively solves the problems of uneven temperature distribution, incomplete solvent evaporation and serious energy waste in the prior art, greatly improves the efficiency of the wet mixing and rotary drum devolatilization process, reduces the energy consumption of solvent evaporation, and improves the solvent recovery rate. At the same time, the environmental pollution in the process is effectively controlled, meeting the current energy-saving and environmental protection technical requirements.

[0013] Compared with the prior art, the present application has the following advantages:

[0014] Improve solvent evaporation efficiency: Precise temperature control design and airflow optimization significantly improve the solvent evaporation rate and greatly improve production efficiency.

[0015] Energy saving and environmental protection: The application of waste heat recovery and solvent recovery system effectively reduces energy consumption and improves solvent recovery rate, reducing waste gas emissions.

[0016] Intelligent control system: automation control can optimize process parameters in real time, improve the stability and flexibility of the production process, and reduce human intervention.

[0017] Increase resource utilization: the design of solvent recovery and waste heat recovery system makes the resources more efficiently utilized, reducing production costs.

[0018] In summary, the present application provides a new wet mixing and rotary drum devolatilization process optimization method, which has strong innovation and practicality, and is suitable for various industrial production processes that require wet mixing and solvent volatilization. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0020] Fig. 1 The wet mixing and rotary drum devolatilization process optimization flowchart of the embodiment of the present application;

[0021] Fig. 2 The rotary drum temperature control section and rotating booster layout diagram of the embodiment of the present application;

[0022] Fig. 3 The flow enhancement device and solvent recovery system diagram of the embodiment of the present application;

[0023] Fig. 4 The waste heat recovery system and intelligent control system diagram of the embodiment of the present application. DETAILED DESCRIPTION

[0024] The present application will be described in detail below in combination with the drawings and specific embodiments. It should be noted that in order to make the embodiments more detailed, the following embodiments are the best, preferred embodiments, and other alternative ways can also be used by those skilled in the art to implement; and the drawings are only used to describe the embodiments more specifically, and are not intended to specifically limit the present application.

[0025] It should be noted that in the specification, "one embodiment", "embodiment", "exemplary embodiment", "some embodiments" and the like indicate that the described embodiments can include a specific feature, structure or property, but not necessarily every embodiment includes the specific feature, structure or property. In addition, when a specific feature, structure or property is described in combination with an embodiment, it should be within the knowledge of those skilled in the art to realize this feature, structure or property in combination with other embodiments (whether or not explicitly described).

[0026] Generally, terms can be understood to be contextually dependent. For example, the term "one or more," as used herein, can be used in reference to any feature, structure, or characteristic in either a singular or multiple sense, depending on the context in which it is used. Additionally, the term "based on" can be understood as not necessarily being confined to a set of exclusive factors, but, instead, can allow for existence of other factors not explicitly described, depending on the context.

[0027] Referring to Figs. 1 to 4

[0028] 1. Wet mixing and rotary drum linkage control system

[0029] Temperature and humidity real-time monitoring and feedback control

[0030] During the wet mixing process, humidity and temperature sensors are installed to monitor the moisture and temperature of the material in real time. The sensors input the collected data to the intelligent control system through the data acquisition system. The system automatically adjusts the heating power and air speed of the rotary drum according to the humidity and temperature data fed back by the sensors. Before the material after wet mixing enters the rotary drum, the intelligent control system adjusts the working conditions of the rotary drum according to real-time data to ensure the efficiency and uniformity of the devolatilization process.

[0031] Adaptive control algorithm

[0032] An adaptive PID control algorithm is used to automatically adjust the temperature, humidity, and air flow rate during the wet mixing and rotary drum devolatilization processes. The solvent evaporation rate during the wet mixing process is closely related to the humidity and temperature of the material. The intelligent control system optimizes the devolatilization parameters based on real-time feedback of humidity and temperature data to ensure that each process stage is in the best state, thereby improving production efficiency and avoiding energy waste.

[0033] 2. Multi-section temperature control design of rotary drum

[0034] Multi-zone temperature control design

[0035] Multiple independent temperature control zones are set inside the rotary drum, and each zone adjusts the temperature independently according to the different evaporation needs of the material. A lower temperature zone is set at the feed end of the rotary drum to preliminarily heat the material and start solvent evaporation; a medium temperature zone is set in the middle to continue heating and accelerate solvent evaporation; and a higher temperature zone is set at the discharge end to ensure complete evaporation of the solvent in the material. Each temperature control zone is controlled by an independent temperature control system to ensure uniform temperature distribution and avoid local overheating or incomplete solvent evaporation.

[0036] Temperature control device

[0037] Each temperature control section uses high-precision temperature sensors and heating elements (such as electric heating tubes, steam heating tubes) to adjust the heating power and temperature of each section in real time through an intelligent control system, to ensure the uniformity and stability of the temperature inside the rotary drum. The temperature control system automatically adjusts the heating power based on the preset temperature gradient and real-time feedback data, preventing local overheating or excessively low temperature from causing material damage or energy waste.

[0038] 3. Optimization of material flow mechanism

[0039] Rotary booster design

[0040] A spiral rotary booster is installed inside the rotary drum. The rotary booster rotates to bring the material along the drum axis, ensuring sufficient contact between the material and the air, and promoting solvent evaporation. The rotation speed of the booster is adjusted according to the characteristics of the material (such as moisture content and particle size) to maintain optimal material flow and evaporation effect. The rotary booster can effectively increase the contact area between the material and the heated air, thereby accelerating the solvent evaporation process.

[0041] Air flow enhancement device

[0042] The rotary drum is equipped with a high-efficiency air flow distribution system, which uses a pressurized air blower and air duct adjustment device to ensure uniform air distribution inside the rotary drum. The air speed and direction can be adjusted in real time through an intelligent control system to ensure optimal cooperation between the air flow and the material, avoiding material stagnation or incomplete solvent evaporation caused by uneven air flow. This air flow enhancement system greatly improves the solvent evaporation efficiency and reduces energy waste.

[0043] 4. Solvent recovery and reuse system

[0044] Solvent recovery device

[0045] The exhaust gas after rotary drum devolatilization is treated by a condensing device. The condenser uses a double-pipe design, with the cooling medium flowing through the outer pipe and the exhaust gas being cooled through the inner pipe, allowing the solvent to be separated from the exhaust gas. The condensed solvent is removed of impurities through a precision filtration and separation device, and then input into the wet mixing process for reuse. This solvent recovery device has a high solvent recovery rate, ensuring that the recovered solvent meets the purity requirements of the wet mixing process.

[0046] Solvent reuse system

[0047] The treated recovered solvent is returned to the wet mixing process through a storage device, forming a closed-loop recycling system. The system can adjust the amount and temperature of the solvent return according to actual needs, ensuring that the concentration and humidity of the solvent in the wet mixing process are within the optimal range. Through this solvent reuse system, not only is the consumption of solvent reduced, but also the procurement cost of solvent is reduced, and the environmental pollution caused by solvent emissions is reduced.

[0048] 5. Energy saving and waste heat recovery

[0049] Waste heat recovery system

[0050] The waste heat generated during the devolatilization process of the rotary drum is recovered through a heat exchanger. The waste heat is used to preheat the materials or solvents in the wet mixing process. The heat exchanger uses high-efficiency heat exchange materials and design to ensure that the waste heat recovery rate reaches more than 90%. The recovered heat is used to heat the feed material or water, reducing the consumption of external energy and significantly reducing energy costs.

[0051] Solar auxiliary system

[0052] In a suitable production environment, install a solar water heating system to provide heat to the heating system of the rotary drum through solar energy. The solar system works with the waste heat recovery system to reduce traditional energy consumption and meet the energy-saving and environmentally friendly production requirements.

[0053] Example 1 (wet mixing of high molecular materials and rotary drum devolatilization process)

[0054] In this example, wet mixing and rotary drum devolatilization process are used to process high molecular materials. The high molecular materials are mixed with NMP (N-methyl pyrrolidone) solvent, and then the solvent is devolatilized through the rotary drum. The inner diameter of the rotary drum is 1.5 meters, the length is 3 meters, and the working temperature is set to 80℃, 100℃, 130℃ three sections to ensure that the solvent is gradually volatilized and reaches the appropriate recovery rate.

[0055] Wet mixing process

[0056] During the mixing process, high molecular materials are mixed with NMP solvent to ensure uniform distribution of the solvent in the material. The wet mixing equipment is equipped with a stirrer to provide sufficient shear force to promote the mixing of the solvent and the material.

[0057] Rotary drum devolatilization process

[0058] In the rotary drum, the material is contacted with hot air through rotation, and the solvent is volatilized and carried away by the air flow. The air flow rate in the rotary drum is set to 4 m / s, and the volatilization rate is calculated by the following formula:

[0059]

[0060] The volatilization rate (g / s) is calculated by the following formula:

[0061] k evap The volatilization coefficient (m / s) is selected according to the characteristics of different materials and solvents;

[0062] A is the contact area in the rotary drum (m 2 ), assuming a contact area of 4.5 m 2 ;

[0063] P vapor is the vapor pressure of NMP (Pa), approximately 40.5 kPa at 80℃;

[0064] P ambient is the ambient air pressure (Pa), typically 101.3 kPa;

[0065] At an air flow rate of 4 m / s, the volatilization rate per hour is 500 g.

[0066] Solvent recovery system

[0067] The solvent recovery system uses a condensing device to condense and recover the NMP solvent volatilized into the air stream. The recovery rate is calculated by the following formula:

[0068]

[0069] R recovery is the solvent recovery rate (%);

[0070] m recovered is the mass of recovered solvent (g);

[0071] m total is the total mass of original solvent (g);

[0072] Through this process, the recovery rate of NMP solvent can reach 98%.

[0073] Rotary drum temperature control

[0074] The heating system of the rotary drum is set with three-stage temperature control sections, with temperatures set at 80℃, 100℃ and 130℃ respectively. The heating power of each section can be calculated by the following formula:

[0075] Q = m · C · ΔT

[0076] Q is the required heating power (J);

[0077] m is the mass of the material (kg), assuming a material mass of 200 kg;

[0078] C is the specific heat capacity of the material (J / kg·℃), assuming a specific heat capacity of 1.5 J / kg·℃;

[0079] ΔT is the temperature change (℃), assuming a temperature change from 80℃ to 130℃, i.e. ΔT = 50℃;

[0080] The required heating power for each temperature control section is calculated as:

[0081] Q = 200 · 1.5 · 50 = 15,000 J

[0082] The heating power requirement of each temperature control section is 15 kW, ensuring the best solvent volatilization effect.

[0083] Airflow enhancement and material flow mechanism

[0084] To enhance the contact effect of airflow and material, a spiral rotating booster is installed in the rotary drum, with a wind speed of 4 m / s, ensuring uniform flow of materials and efficient volatilization of solvents. The airflow enhancement device and temperature control system work together to optimize the distribution of airflow and improve the efficiency of solvent volatilization.

[0085] Waste heat recovery

[0086] A waste heat recovery device is installed at the exhaust end of the rotary drum to recover the waste heat in the airflow through a heat exchanger, improving the energy utilization efficiency of the process. The waste heat recovery efficiency is calculated by the following formula:

[0087]

[0088] η heat Waste heat recovery efficiency (%);

[0089] Q recovered Recovered heat (J);

[0090] Q total Original heat (J).

[0091] By optimizing the waste heat recovery system, energy consumption can be effectively reduced and the overall efficiency of the system can be improved.

[0092] Example 2 (wet mixing and devolatilization process of lithium battery slurry)

[0093] This example is used for the wet mixing and solvent (such as NMP) devolatilization process of lithium battery anode material slurry. The rotary drum devolatilization process similar to Example 1 is adopted, but the solvent recovery efficiency requirement is higher. The airflow rate in the rotary drum is set to 6 m / s to increase the volatilization rate, and the recovery system uses a more efficient condensing device, with a recovery rate of 99%. The volatilization rate is calculated using the same formula as above:

[0094]

[0095] By optimizing the airflow and temperature control system, the solvent volatilization efficiency is improved, and the solvent recovery rate reaches 99%, providing efficient process guarantee for the production of lithium battery slurry.

[0096] Example 3 (wet mixing and rotary drum devolatilization process of chemical powder)

[0097] This example is for the wet mixing of chemical powders (pigments, paints) and the devolatilization process of the aqueous solvent (e.g. water) using the rotary drum temperature control and airflow enhancement system. The calculation of the volatilization rate and solvent recovery rate is similar to Example 1, but since the solvent being processed is aqueous, the recovery system is simpler. The calculation formula used by the temperature control system is:

[0098] Q = m · C · ΔT

[0099] The temperature of the material is heated from 70°C to 90°C, and the heating power is calculated as follows:

[0100] Q = 200 · 4.2 · 20 = 16,800 J

[0101] Example 4 (wet mixing and devolatilization process of ceramic raw materials)

[0102] This example is for the wet mixing and moisture devolatilization of ceramic raw materials. The temperature control section is 70°C, 90°C, and the moisture content of the material is relatively high, so the temperature control system is relatively simple, and the focus is on the uniform volatilization of moisture. The solvent recovery system mainly processes water vapor, and the energy consumption is optimized by the rate of moisture evaporation and waste heat recovery.

[0103] The heating power of the rotary drum and the airflow rate are optimized using the above calculation formula, ensuring that the moisture in the ceramic raw materials is fully volatilized.

[0104] The present application encompasses any substitutions, modifications, equivalent methods and solutions made on the essence and scope of the present application. In order for the public to have a thorough understanding of the present application, specific details are described in the following preferred embodiments of the present application, and the present application can also be fully understood without the description of these details by those skilled in the art. In addition, in order to avoid unnecessary confusion to the essence of the present application, well-known methods, processes, procedures, elements and circuits, etc. are not described in detail.

[0105] The above is only the preferred embodiment of the present application, and it should be noted that for ordinary skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can also be made, which should be considered as the protection scope of the present application.

Claims

1. A process optimization method combining wet mixing and rotary drum devolatilization, characterized by, The intelligent control system is used to link the wet mixing and rotary drum devolatilization processes. The specific steps include: During the wet mixing process, the moisture and temperature of the material are monitored in real time, and the working conditions of the rotary drum are adjusted according to the data feedback from the sensors. In the rotary drum, multiple independent temperature control sections are set up, and the temperature of each section is adjusted independently according to the volatilization requirements of the material. A rotary booster is installed in the rotary drum to enhance the flowability of the material and increase the contact area between the material and the heated air. An airflow enhancement device is set up in the rotary drum to optimize airflow distribution and improve solvent volatilization efficiency. A solvent recovery system is configured to recover solvent from waste gas and return the solvent to the wet mixing process after precise filtration. The volatilization rate is calculated by the following formula: k is the evaporation rate, k evap A is the contact area (m 2 ), P vapor P is the vapor pressure of NMP (Pa), P ambient P is the ambient pressure (Pa).

2. The process optimization method of claim 1, wherein, The intelligent control system uses an adaptive PID control algorithm to automatically adjust the temperature, humidity, and airflow rate during the wet mixing and rotary drum devolatilization processes to optimize the working conditions of each process.

3. The process optimization method of claim 1, wherein, The temperature control system of the rotary drum includes multiple independent temperature control sections, each of which adjusts the temperature through a temperature control device, and the temperature values of the sections gradually increase according to the volatilization requirements of the material. The temperature adjustment power is calculated by the following formula: Q = m·C·ΔT Q is the required heating power, m is the mass of the material, C is the specific heat capacity of the material, and ΔT is the temperature change.

4. The process optimization method of claim 1, wherein, The rotary booster in the rotary drum is spiral-shaped, which makes the material flow along the drum axis and enhances the contact between the material and the air, thereby improving the volatilization efficiency of the solvent.

5. The process optimization method of claim 1, wherein, The airflow enhancement device in the rotary drum includes a pressurized fan and an air duct adjustment device to ensure uniform airflow distribution in the rotary drum, thereby promoting solvent volatilization.

6. The process optimization method of claim 1, wherein, The solvent recovery system condenses and separates the solvent in the waste gas through a condenser. The condensed solvent is purified through a filtration device and then reused in the wet mixing process.

7. The process optimization method of claim 1, wherein, The process also includes a waste heat recovery system that recovers waste heat from the rotary drum through a heat exchanger and uses the recovered heat to preheat the material and solvent in the wet mixing process. The waste heat recovery rate is calculated by the following formula: η heat is the waste heat recovery efficiency, Q recovered is the recovered heat, Q total is the original heat.

8. The process optimization method of claim 7, wherein, The waste heat recovery system recovers waste heat from the rotary drum through a heat exchanger, which is used to heat the incoming material and solvent, thereby reducing the consumption of external energy.

9. The process optimization method of claim 1, wherein, The intelligent control system also includes an adjustment function based on material characteristics, which can adjust the heating power, airflow rate, and material flowability of the rotary drum in real time according to the moisture, temperature, and volatilization parameters of the material.

10. The process optimization method of claim 1, wherein, The solvent recovery system includes a set of solvent separation device and filtration system, which recovers and processes the solvent in the waste gas through separation technology.

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