A system for the production of a ceramic sand proppant

Abstract

This invention discloses a system for preparing ceramsite proppant, belonging to the field of ceramsite preparation. It includes crushing, batching, grinding, and pelletizing processes. After pelletizing, the raw materials become semi-finished products, which are then fed into a kiln for calcination. The calcination process is controlled by a temperature control mode. This temperature control mode is used to regulate the kiln temperature during calcination. The temperature control mode controls the calcination process based on the feeding status. This application utilizes a low-temperature slow-firing strategy or a high-temperature fast-firing strategy to control the temperature during calcination while maintaining a constant amount of semi-finished product entering the kiln. Furthermore, by dividing the kiln interior into zones and controlling the flame diffusion range of the calcination zone, the area of ​​the calcination zone is effectively increased, thereby increasing the residence time of the semi-finished product in the firing zone, and ultimately ensuring that the quality of the calcined ceramsite better meets technical requirements.

Description

Technical Field

[0001] This invention relates to the field of ceramsite sand preparation technology, specifically to a ceramsite sand proppant preparation system. Background Technology

[0002] Ceramsite sand is a type of ceramic particle product with high fracturing strength. It is mainly used for downhole support in oil fields to increase oil and gas production and is considered an environmentally friendly product. In simple terms, the production of ceramsite sand as a proppant can be summarized into processes such as crushing, batching, grinding, pelletizing, calcination, coal powder preparation, finished product cooling, screening, and packaging.

[0003] Temperature control during calcination directly affects the quality of the finished ceramsite sand. Currently, the temperature inside the kiln is mainly controlled manually by adjusting the amount of fuel based on experience. However, the instability of manual control leads to unstable temperatures inside the kiln, which in turn makes it impossible to guarantee product quality. Summary of the Invention

[0004] To address the problems of existing technologies, this invention provides a ceramic aggregate proppant preparation system, comprising: crushing-batching-grinding-ball-making processes. After the raw materials undergo the ball-making process, they become semi-finished products, which are then sent to a kiln for calcination. The calcination process is controlled by a temperature control mode.

[0005] The temperature control mode is used to regulate the temperature of the kiln during the calcination process; the temperature control mode controls the calcination process based on the feeding status.

[0006] The temperature control modes include: a first control mode and a second control mode;

[0007] The first control mode controls the calcination process based on the feeding state of the semi-finished product, while the second control mode controls the calcination process based on the flame length ejected from the fuel pipe in the kiln.

[0008] The feeding states include: a first state and a second state;

[0009] The first state is when the amount of semi-finished product entering the kiln remains unchanged; the second state is when the amount of semi-finished product entering the kiln changes.

[0010] Before adjusting the temperature, the combustion temperature, kiln speed and blower speed that match the amount of fuel entering the kiln are selected as initial parameters based on historical data. The initial parameters of the corresponding equipment participating in the kiln calcination process are set, and all equipment participating in the kiln calcination process is connected to the PLC.

[0011] If the amount of semi-finished product entering the kiln remains unchanged, the calcination process is carried out using either the low-temperature slow-firing strategy or the high-temperature fast-firing strategy of the first control mode.

[0012] The low-temperature slow-fire strategy is achieved by adjusting the kiln speed and combustion temperature. The kiln speed is based on the speed of the motor (the motor that drives the kiln), and the combustion temperature is based on the valve opening on the fuel delivery pipeline. By constructing a motor speed-valve opening image, the motor speed and valve opening are linked one-to-one. When the operating parameter of either the motor speed or the valve opening is reduced, the corresponding operating parameter of the other is reduced accordingly. That is, the valve opening is directly proportional to the motor speed.

[0013] The learning model is fed with a large amount of data on kiln dimensions, semi-finished product feed rate, semi-finished product moisture content, kiln inclination angle, heat source type, kiln rotation speed, and firing temperature based on the firing quality of the target product. Through multiple iterations of training, a theoretically optimal firing temperature and optimal kiln rotation speed are obtained that best approximate the firing quality of the target product with a fixed feed rate. When the actual semi-finished product is fed into the kiln in a fixed quantity, the theoretically optimal firing temperature and optimal kiln rotation speed obtained from the training are matched to the current calcination process through the PLC. When the combustion is stable, a low-temperature slow firing strategy can be adopted. That is, the kiln rotation speed is adjusted through the PLC to match the kiln rotation speed with the feed rate. The kiln rotation speed and firing temperature are dynamically adjusted, that is, the motor speed and valve opening are controlled by the PLC.

[0014] The high-temperature fast-burning strategy is the opposite of the low-temperature slow-burning strategy, which involves increasing the valve opening and motor speed in conjunction with the temperature.

[0015] If the amount of semi-finished product entering the kiln changes, the kiln speed is set to remain constant, the motor operates according to the initial parameters, and the combustion temperature control strategy of the first control mode is adopted to regulate the combustion temperature of the kiln.

[0016] When the amount of semi-finished products entering the kiln increases, the opening of the valve is increased by the PLC, which increases the amount of fuel entering the kiln and raises the firing temperature; conversely, the opening of the valve is decreased. After the calcination process stabilizes, the calcination process can be switched to a low-temperature slow firing strategy or a high-temperature fast firing strategy as needed.

[0017] The interior of the kiln is divided into a preheating zone, a firing zone, and a cooling zone according to the direction of movement of the semi-finished product in the kiln. The preheating zone is located near the kiln tail, and the cooling zone is located near the kiln head. The quality of the ceramsite sand mainly depends on the control of the calcination process in the firing zone. By increasing the calcination time of the semi-finished product in the firing zone, the quality of the ceramsite sand can be significantly improved.

[0018] The residence time of the semi-finished product in the firing zone is increased by increasing the area of ​​the firing zone, which is achieved by controlling the length of the flame. The control of the flame length includes at least the control of the blower suction force at the kiln tail and the opening degree of the valve.

[0019] The calcination process of the semi-finished product is controlled by using either the first control mode or the second control mode alone, or by combining the first control mode and the second control mode.

[0020] Furthermore, the temperature control mode includes a storage module for storing the first control mode and the second control mode, as well as storing the equipment operating parameters involved in the kiln calcination process.

[0021] Furthermore, the storage module is equipped with a parameter monitoring module connected to the PLC. The parameter monitoring module is used to monitor the operating status of the equipment during the calcination process. The operating status is determined based on the comparison of the equipment's operating parameters with threshold parameters.

[0022] Furthermore, the parameter monitoring module includes a data acquisition unit, a data comparison unit, and a data retrieval unit;

[0023] The data acquisition unit is used to acquire the real-time operating parameters of each piece of equipment involved in the calcination process;

[0024] The data comparison unit is equipped with the threshold parameter, which is used to compare the real-time operating parameters of the device with the threshold parameter and send the comparison result to the PLC.

[0025] The data retrieval unit is used to periodically retrieve and send the data from the data acquisition unit to the data comparison unit.

[0026] Furthermore, the length of the flame is represented by constructing a valve opening-fan suction image with the valve opening as the horizontal axis and the fan suction force as the vertical axis. The area of ​​the constructed valve opening and fan suction image is represented by the flame spray range, that is, the area of ​​the burning zone. According to the required burning zone area, the parameters of valve opening and fan suction force are controlled by PLC to expand the burning zone area.

[0027] Furthermore, a kiln head cover and a kiln tail cover are respectively installed at the kiln tail and the kiln head.

[0028] A pipe is installed between the top of the kiln head hood and the kiln tail hood. An axial flow fan connected to the pipe is installed near the kiln tail hood. The axial flow fan, controlled by a PLC, can transport the heat flow from the cooling zone to the preheating zone, thereby raising the temperature of the preheating zone. When the semi-finished product enters the kiln, the preheating effect in the preheating zone is improved, which is beneficial to improving the quality of the finished product.

[0029] Furthermore, the PLC is equipped with a fuel characteristic adaptive algorithm based on fuel.

[0030] The fuel characteristic adaptive algorithm automatically identifies fuel calorific value and combustion rate parameters when switching fuel types, and reconstructs the linkage relationship between valve opening, fan speed and kiln speed through fuzzy control algorithm to ensure calcination stability under different fuels.

[0031] The PLC is equipped with a fuel library, which stores the calorific value range of various fuels and calorific value correction coefficients. When a fuel type switching signal is detected, the basic calorific value parameters of the corresponding fuel are automatically retrieved as the initial value.

[0032] The fuel type is determined by installing a gas chromatograph and an infrared spectrometer wirelessly connected to a PLC on the fuel pipeline. The gas chromatograph is used to identify gaseous fuels, and the infrared spectrometer is used to identify stationary fuels.

[0033] The beneficial effects of this invention are:

[0034] This application utilizes a low-temperature slow-firing strategy or a high-temperature fast-firing strategy to control the temperature during the calcination process while keeping the amount of semi-finished product entering the kiln constant. Furthermore, by dividing the interior of the kiln into zones and controlling the flame diffusion range of the calcination zone, the area of ​​the calcination zone can be effectively increased, thereby increasing the residence time of the semi-finished product in the firing zone. This results in ceramsite sand of higher quality. Additionally, by installing an insulation sleeve outside the kiln in conjunction with the firing zone, the temperature control of the calcination process can be made more precise. Attached Figure Description

[0035] Figure 1 A schematic diagram of the first control mode provided by the present invention;

[0036] Figure 2 This is a schematic diagram illustrating the principle of the second control mode provided by the present invention. Detailed Implementation

[0037] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the present invention

[0038] All other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention.

[0039] Please see Figures 1 to 2 This invention provides a system for preparing ceramsite sand proppant, comprising:

[0040] The process of crushing, batching, grinding, and pelletizing involves the raw materials being processed into semi-finished products, which are then sent to a kiln for calcination. The calcination process is controlled by a temperature control mode.

[0041] The temperature control mode is used to regulate the temperature of the kiln during the calcination process; the temperature control mode controls the calcination process based on the feeding status.

[0042] The temperature control modes include: a first control mode and a second control mode;

[0043] The first control mode controls the calcination process based on the feeding state of the semi-finished product, while the second control mode controls the calcination process based on the flame length ejected from the fuel pipe in the kiln.

[0044] The feeding states include: a first state and a second state;

[0045] The first state is that the amount of semi-finished products entering the kiln remains unchanged, which can be understood as the same amount of semi-finished products entering the kiln in the current period and the same amount of semi-finished products entering the kiln in each subsequent period. The second state is that the amount of semi-finished products entering the kiln changes, which can be understood as the different amount of semi-finished products entering the kiln in the current period and the different amount of semi-finished products entering the kiln in each subsequent period.

[0046] Before adjusting the temperature, the combustion temperature, kiln speed and blower speed that match the amount of fuel entering the kiln are selected as initial parameters based on historical data. The initial parameters of the corresponding equipment participating in the kiln calcination process are set, and all equipment participating in the kiln calcination process is connected to the PLC.

[0047] If the amount of semi-finished product entering the kiln remains unchanged, the calcination process is carried out using either the low-temperature slow-firing strategy or the high-temperature fast-firing strategy of the first control mode.

[0048] The low-temperature slow-fire strategy is achieved by adjusting the kiln speed and combustion temperature. The kiln speed is based on the speed of the motor (the motor that drives the kiln), and the combustion temperature is based on the valve opening on the fuel delivery pipeline. By constructing a motor speed-valve opening image, the motor speed and valve opening are linked one-to-one. When the operating parameter of either the motor speed or the valve opening is reduced, the corresponding operating parameter of the other is reduced accordingly. That is, the valve opening is directly proportional to the motor speed.

[0049] The learning model is trained by inputting a large amount of data on kiln dimensions, semi-finished product feed rate, semi-finished product moisture content, kiln inclination angle, heat source type, kiln rotation speed, and firing temperature based on the firing quality of the target product. Through multiple iterations, a theoretically optimal firing temperature and optimal kiln rotation speed are obtained that best approximate the firing quality of the target product with a fixed feed rate. When the actual semi-finished product feeds into the kiln in a fixed quantity, the theoretically optimal firing temperature and optimal kiln rotation speed obtained through training are matched to the current calcination process via PLC. This state may not be the best state compared to the actual state. Based on the final quality of the fired product, the learning model can be trained again for the same material and the same feed rate of semi-finished product, and the relevant data can be output to adjust the optimal firing temperature and optimal kiln rotation speed. Alternatively, for energy saving, a low-temperature slow firing strategy can be adopted, that is, the kiln rotation speed can be adjusted by PLC to match the kiln rotation speed with the feed rate. The kiln rotation speed and firing temperature can be dynamically adjusted by PLC controlling the motor speed and valve opening.

[0050] The high-temperature fast-burning strategy is the opposite of the low-temperature slow-burning strategy, which involves increasing the valve opening and motor speed in conjunction with the temperature.

[0051] If the amount of semi-finished product entering the kiln changes, the kiln speed is set to remain constant, the motor operates according to the initial parameters, and the combustion temperature control strategy of the first control mode is adopted to regulate the combustion temperature of the kiln.

[0052] When the amount of semi-finished products entering the kiln increases, the opening of the valve is increased by the PLC to increase the amount of fuel entering the kiln and increase the firing temperature; conversely, the opening of the valve is decreased. After the calcination process is stable, the calcination process can be switched to a low-temperature slow firing strategy or a high-temperature fast firing strategy as needed.

[0053] The interior of the kiln is divided into a preheating zone, a firing zone, and a cooling zone according to the direction of movement of the semi-finished product in the kiln. The preheating zone is located near the kiln tail, and the cooling zone is located near the kiln head. The quality of the ceramsite sand mainly depends on the control of the calcination process in the firing zone. By increasing the calcination time of the semi-finished product in the firing zone, the quality of the ceramsite sand can be significantly improved.

[0054] The residence time of the semi-finished product in the firing zone is increased by increasing the area of ​​the firing zone, which is achieved by controlling the length of the flame. The control of the flame length includes at least the control of the blower suction force at the kiln tail and the opening degree of the valve.

[0055] The length of the flame is represented by constructing a valve opening-fan suction force image with valve opening as the horizontal axis and fan suction force as the vertical axis. The area of ​​the constructed valve opening and fan suction force image is represented by the flame spray range, that is, the area of ​​the burning zone. According to the required burning zone area, the parameters of valve opening and fan suction force are controlled by PLC to expand the burning zone area.

[0056] The inventive point of this application is that the calcination process of the semi-finished product is based on the use of either the first control mode or the second control mode alone, or the combination of the first control mode and the second control mode, to control the calcination process of the semi-finished product in the kiln, and to improve the preheating effect by increasing the temperature of the preheating zone through temperature retraction as described below, thereby facilitating the control of the temperature of the firing zone, and enabling the preparation of ceramsite sand under the requirements of energy saving and high efficiency.

[0057] In addition, the temperature control mode also includes a storage module for storing the first control mode and the second control mode, as well as storing the equipment operating parameters involved in the kiln calcination process.

[0058] The storage module is equipped with a parameter monitoring module connected to the PLC. The parameter monitoring module is used to monitor the operating status of the equipment during the calcination process. The operating status is determined based on the comparison of the equipment's operating parameters with threshold parameters.

[0059] The parameter monitoring module is equipped with a data acquisition unit, a data comparison unit, and a data retrieval unit.

[0060] The data acquisition unit is used to acquire the real-time operating parameters of each piece of equipment involved in the calcination process;

[0061] The data comparison unit is equipped with the threshold parameter, which is used to compare the real-time operating parameters of the device with the threshold parameter and send the comparison result to the PLC.

[0062] The data retrieval unit is used to periodically retrieve and send the data from the data acquisition unit to the data comparison unit.

[0063] In some embodiments, a kiln head cover and a kiln tail cover are respectively provided at the kiln tail and the kiln head.

[0064] A pipe is installed between the top of the kiln head hood and the kiln tail hood. An axial flow fan connected to the pipe is installed near the kiln tail hood. The axial flow fan, controlled by a PLC, can transport the heat flow from the cooling zone to the preheating zone, thereby raising the temperature of the preheating zone. When the semi-finished product enters the kiln, the preheating effect in the preheating zone is improved, which is beneficial to improving the quality of the finished product.

[0065] The PLC is equipped with a fuel characteristic adaptive algorithm based on fuel.

[0066] The fuel characteristic adaptive algorithm automatically identifies fuel calorific value and combustion rate parameters when switching fuel types, and reconstructs the linkage relationship between valve opening, fan speed and kiln speed through fuzzy control algorithm to ensure calcination stability under different fuels.

[0067] The PLC is equipped with a fuel library, which stores the calorific value range of various fuels and calorific value correction coefficients. When a fuel type switching signal is detected, the basic calorific value parameters of the corresponding fuel are automatically retrieved as the initial value.

[0068] The fuel type is determined by installing a gas chromatograph and an infrared spectrometer wirelessly connected to a PLC on the fuel pipeline. The gas chromatograph is used to identify gaseous fuels, and the infrared spectrometer is used to identify stationary fuels.

[0069] When switching fuel types, the PLC can quickly and accurately obtain the calorific value and combustion rate parameters through the set fuel library, and reconstruct the linkage relationship of the equipment through the fuzzy control algorithm. Compared with the traditional manual switching mode, the parameter recognition efficiency is improved, the combustion stability is improved, and the problem of multi-fuel adaptability is effectively solved.

[0070] In order to improve the quality of ceramsite sand and minimize the variation in particle size of semi-finished products, the process of this product can be controlled more precisely to improve the quality of the product and reduce the fluctuation range of particle size. The particle size of the semi-finished product can be controlled through the pelletizing module.

[0071] The pelletizing module includes: a parameter control module, an optimization module, and a humidity monitoring module.

[0072] The pelletizing module determines the parameter indicators based on the diameter and rated speed of the pelletizing machine and the physical properties of the raw materials, and based on the parameter indicators, the PLC drives the dry powder conveying motor and water pump to work.

[0073] The parameter control module determines parameter indicators based on a parameter determination model. The process of establishing the parameter determination model is as follows:

[0074] A large number of mapping relationships between initiator particles of different sizes and water-to-powder ratio, rotation speed, and rotation time were obtained and labeled by human experts. Based on the mapping relationships, particle size-water-to-powder ratio pairs, particle size-rotation speed pairs, and particle size-rotation time pairs were generated and formed into a training set.

[0075] The training set is input into the neural network model for iterative training to obtain a parameter determination model based on particle size, output water-to-powder ratio, rotation speed, and rotation time.

[0076] The function of the optimization unit is to increase the sampling rate of the product and quickly determine whether the particle size of the product meets the requirements, or whether the variation in particle size of the semi-finished products meets the requirements.

[0077] The optimization module includes: an image acquisition unit and an image analysis unit;

[0078] The image acquisition unit is used to acquire particle images during the granulation process in the pelletizing machine, and send the acquired particle images to the image analysis unit;

[0079] The image acquisition process includes: manually sampling semi-finished products from the granulator multiple times at irregular intervals based on experience; taking photos of the sampled semi-finished products in a flattened state using a high-definition camera; sending the photos to a computer; and analyzing the appearance indicators of the semi-finished products using an image analysis unit within the computer to determine whether the semi-finished products meet the expected requirements; or, judging and analyzing the sampled semi-finished products from the granulator based on manual experience to determine whether the semi-finished products meet the expected requirements.

[0080] The image analysis unit is equipped with preset parameters and standard images. The standard images are preset after the appearance image of the extracted semi-finished product is judged by humans to meet the requirements. The image analysis unit compares the received semi-finished product image with the standard image to obtain the deviation. If the deviation is within the preset parameter range, the first signal is fed back to the PLC. The PLC controls the motor driving the ball forming machine to stop working, ending the processing of the current batch of this product. At the same time, the PLC and the alarm are linked. Based on the comparison result, the alarm flashes different lights and emits different alarm sounds to indicate to the worker that the signal was sent successfully.

[0081] Conversely, if the deviation exceeds the preset parameter range, the parameter determination model is optimized until the deviation between the semi-finished product image obtained during the granulation process according to the output parameters of water-powder ratio, rotation speed, and rotation time and the standard image is within the preset parameter range.

[0082] During the granulation process, the PLC controls the output of the dry powder conveying motor and water pump, and the PLC is linked with the alarm in real time. Different alarm sounds are issued according to the comparison results to alert the staff. The preset parameters include: density, volume and sphericity.

[0083] The humidity detection module is used to detect the humidity of manually sampled semi-finished products during the granulation process. The humidity judgment is based on whether the moisture content of the semi-finished product meets the standard. If the moisture content of the semi-finished product is within the target moisture content range, the humidity of the semi-finished product is determined to be qualified, and then it is transferred to the next process, namely, the semi-finished product is temporarily stored. If the moisture content of the semi-finished product exceeds the target moisture content range, the humidity of the semi-finished product is determined to be unqualified. Then, the powder adding device is controlled by PLC to add powder or the water pump is controlled to add water until the humidity of the sampled semi-finished product is within the preset humidity parameter range. Then, the optimization module process is restarted again.

[0084] The image analysis unit includes: a comparison unit;

[0085] The standard image is set in the comparison unit. The comparison unit divides the standard image into a first grid area, marks the image in the first grid area with a first mark, and each grid has a corresponding identifier. Images that meet the appearance requirements are selected from the first marks. The selected images are marked with a second mark. The ratio of the area of ​​the first identifier to the area of ​​the second identifier is calculated, and the ratio is used as the preset parameter.

[0086] The semi-finished product image acquired by the image acquisition unit is divided into a second grid region. Using the second identifier as a reference, the image within the second grid region is marked with a reference identifier. The ratio of the area of ​​the reference identifier to the area of ​​the second grid region is calculated, and this ratio is recorded as an actual parameter.

[0087] The first grid region and the second grid region have the same area and the same number of grids. If the actual parameter is greater than the preset parameter, the next process is performed; otherwise, the parameter-determined model continues to be trained.

[0088] The appearance of semi-finished products is judged based on roundness, sphericity, and burr indicators.

[0089] Judgment of roundness index

[0090] 1. Contour extraction and preprocessing:

[0091] Image segmentation: The semi-finished product image (second grid region) is binarized, and the contour edges of the semi-finished product are extracted by threshold segmentation or edge detection (such as the Canny operator).

[0092] Contour smoothing: Use Gaussian filtering or morphological operations (such as closing operations) to remove noise on the contour and avoid burrs interfering with roundness calculations.

[0093] 2. Circularity Quantization Calculation:

[0094] Local roundness analysis within the grid area: For each second grid area, the contour is extracted and the roundness is calculated separately. If the roundness of the contour within the grid is lower than the threshold, it is marked as a "non-circular area", and its area is included in the calculation of the baseline identification area.

[0095] Sphericity index analysis: By acquiring images from multiple perspectives (such as top and side views), the roundness of each perspective is calculated, and the average value is taken as an approximate value of sphericity.

[0096] Axis ratio calculation: Fit an ellipse to the 2D contour to obtain the major axis (a) and minor axis (b). Assuming the third axis in 3D is c (which can be estimated through standard image presets or empirical values), the sphericity is approximately:

[0097] sphericity = (The sphericity of a theoretical sphere is 1; the smaller the value, the further it deviates from the sphere.)

[0098] Sphericity integration within grid areas: If the sphericity of each grid area meets the standard (e.g., close to 1), it is marked as a "spherical area". Its area ratio is included in the actual parameter calculation and compared with the preset parameter (the proportion of sphericity qualified areas of the standard image).

[0099] Burr Index Analysis

[0100] 1. Burr feature detection:

[0101] Edge curvature analysis: Calculate the local curvature of contour points. Points with abrupt changes in curvature (sharp protrusions) are potential burr points. Set a curvature threshold; points exceeding the threshold are considered burr points. Connect adjacent burr points to form a burr region.

[0102] Morphological operations: Use erosion (for small structural elements) to remove contour burrs, and calculate the difference in contour area or perimeter before and after erosion. The larger the difference, the more severe the burrs. Alternatively, use dilation to highlight the burrs, and then compare them with the original contour to extract the burr area.

[0103] 2. Burr quantification and marking:

[0104] Burr area ratio: Calculate the ratio of the area of ​​the burr region to the area of ​​the grid region. If the ratio exceeds the threshold, the grid is marked as a "burr defect region".

[0105] Burr quantity and length: Count the number and average length of burrs in each grid as the basis for calculating the benchmark area (e.g., burr areas are not included in the qualified area).

[0106] 3. Indicator integration and parameter calculation:

[0107] Single grid area analysis: For each second grid area, calculate the roundness, sphericity, and burr index respectively. If all three meet the standards (e.g., roundness ≥ 0.9, sphericity ≥ 0.8, burr area ratio ≤ 5%), then mark the grid as a "qualified area" and its area is included in the benchmark identification area.

[0108] 4. Overall parameter calculation:

[0109] Actual parameters = total area of ​​qualified regions / total area of ​​the second grid region; Compare actual parameters with preset parameters (percentage of qualified regions in the standard image): If actual parameters > preset parameters, the semi-finished product is deemed qualified and proceeds to the next process; otherwise, the image is used to input parameters to determine the model, and training is conducted in conjunction with the specific deviations of roundness, sphericity, and burrs to optimize the judgment threshold.

[0110] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing ceramsite sand proppant, comprising crushing, batching, grinding, and pelletizing processes, wherein the raw materials are processed into semi-finished products through the pelletizing process, and the semi-finished products are then sent to a kiln for calcination, characterized in that, The calcination process is controlled by a temperature control mode; The temperature control mode is used to regulate the temperature of the kiln during the calcination process. The temperature control mode controls the calcination process based on the feeding status; The temperature control modes include: a first control mode and a second control mode; The first control mode controls the calcination process based on the feeding state of the semi-finished product, while the second control mode controls the calcination process based on the flame length ejected from the fuel pipe in the kiln. The feeding states include: a first state and a second state; The first state is when the amount of semi-finished product entering the kiln remains unchanged; the second state is when the amount of semi-finished product entering the kiln changes. Before adjusting the temperature, the combustion temperature, kiln speed and blower speed that match the amount of fuel entering the kiln are selected as initial parameters based on historical data. The initial parameters of the corresponding equipment participating in the kiln calcination process are set, and all equipment participating in the kiln calcination process is connected to the PLC. If the amount of semi-finished product entering the kiln remains unchanged, the calcination process is carried out using either the low-temperature slow-firing strategy or the high-temperature fast-firing strategy of the first control mode. The low-temperature slow-fire strategy is achieved by adjusting the kiln speed and combustion temperature. The kiln speed is based on the motor speed, and the combustion temperature is based on the valve opening on the fuel delivery pipeline. By constructing a motor speed-valve opening image, the motor speed and valve opening are linked one-to-one. When the operating parameter of either the motor speed or the valve opening is reduced, the corresponding operating parameter of the other is reduced accordingly. That is, the valve opening is directly proportional to the motor speed. The learning model is trained by inputting a large amount of data on kiln dimensions, semi-finished product feed rate, semi-finished product moisture content, kiln inclination angle, heat source type, kiln rotation speed, and firing temperature based on the firing quality of the target product. Through multiple iterations, a theoretically optimal firing temperature and optimal kiln rotation speed are obtained that best approximate the firing quality of the target product with a fixed feed rate. When the actual semi-finished product is fed into the kiln in a fixed quantity, the PLC matches the theoretically optimal firing temperature and optimal kiln rotation speed obtained from the training process to the current calcination process. After the combustion stabilizes, a low-temperature slow firing strategy is adopted. That is, the kiln rotation speed is adjusted by the PLC to match the kiln rotation speed with the feed rate. The kiln rotation speed and firing temperature are dynamically adjusted by the PLC to control the motor speed and valve opening. The high-temperature fast-burning strategy is the opposite of the low-temperature slow-burning strategy, which involves increasing the valve opening and motor speed. If the amount of semi-finished product entering the kiln changes, the kiln speed is set to remain constant, the motor operates according to the initial parameters, and the combustion temperature control strategy of the first control mode is adopted to regulate the combustion temperature of the kiln. When the amount of semi-finished products entering the kiln increases, the valve opening is increased by the PLC to increase the amount of fuel entering the kiln and raise the firing temperature; conversely, the valve opening is decreased. After the calcination process stabilizes, the calcination process is switched to a low-temperature slow-fire strategy or a high-temperature fast-fire strategy as needed. The interior of the kiln is divided into a preheating zone, a firing zone, and a cooling zone according to the direction of movement of the semi-finished product in the kiln. The preheating zone is located near the kiln tail, and the cooling zone is located near the kiln head. The quality of the ceramsite sand mainly depends on the control of the calcination process in the firing zone. By increasing the calcination time of the semi-finished product in the firing zone, the quality of the ceramsite sand can be significantly improved. The residence time of the semi-finished product in the firing zone is increased by increasing the area of ​​the firing zone, which is achieved by controlling the length of the flame. The control of the flame length includes at least the control of the blower suction force at the kiln tail and the opening degree of the valve. The calcination process of the semi-finished product is controlled by using either the first control mode or the second control mode alone, or by combining the first control mode and the second control mode.

2. The method for preparing ceramsite sand proppant according to claim 1, characterized in that, The temperature control mode includes a storage module for storing the first control mode and the second control mode, as well as storing the equipment operating parameters involved in the kiln calcination process.

3. The method for preparing ceramsite sand proppant according to claim 2, characterized in that, The storage module is equipped with a parameter monitoring module connected to the PLC. The parameter monitoring module is used to monitor the operating status of the equipment during the calcination process. The operating status is determined based on the comparison of the equipment's operating parameters with threshold parameters.

4. The method for preparing ceramsite sand proppant according to claim 3, characterized in that, The parameter monitoring module is equipped with a data acquisition unit, a data comparison unit, and a data retrieval unit. The data acquisition unit is used to acquire the real-time operating parameters of each piece of equipment involved in the calcination process; The data comparison unit is equipped with the threshold parameter, which is used to compare the real-time operating parameters of the device with the threshold parameter and send the comparison result to the PLC. The data retrieval unit is used to periodically retrieve and send the data from the data acquisition unit to the data comparison unit.

5. The method for preparing ceramsite sand proppant according to claim 1, characterized in that, The length of the flame is represented by constructing a valve opening-fan suction image with valve opening as the horizontal axis and fan suction force as the vertical axis. The area of ​​the constructed valve opening and fan suction image represents the flame spray range, that is, the area of ​​the burning zone. According to the required burning zone area, the parameters of valve opening and fan suction force can be controlled by PLC to expand the burning zone area.

6. The method for preparing ceramsite sand proppant according to claim 1, characterized in that, The kiln tail cover and the kiln head cover are respectively installed at the kiln tail and the kiln head. A pipe is installed between the top of the kiln head hood and the kiln tail hood. An axial flow fan connected to the pipe is installed near the kiln tail hood. The axial flow fan is controlled by a PLC to transport the heat flow from the cooling zone to the preheating zone, thereby raising the temperature of the preheating zone. When the semi-finished product enters the kiln, the preheating effect of the preheating zone is improved, which is beneficial to improving the quality of the finished product.

7. The method for preparing ceramsite sand proppant according to claim 1, characterized in that, The PLC is equipped with a fuel characteristic adaptive algorithm based on fuel. The fuel characteristic adaptive algorithm automatically identifies fuel calorific value and combustion rate parameters when switching fuel types, and reconstructs the linkage relationship between valve opening, fan speed and kiln speed through fuzzy control algorithm to ensure calcination stability under different fuels. The PLC is equipped with a fuel library, which stores the calorific value range of various fuels and calorific value correction coefficients. When a fuel type switching signal is detected, the basic calorific value parameters of the corresponding fuel are automatically retrieved as the initial value. The fuel type is determined by installing a gas chromatograph and an infrared spectrometer wirelessly connected to a PLC on the fuel pipeline. The gas chromatograph is used to identify gaseous fuels, and the infrared spectrometer is used to identify solid fuels.

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