A green production quality control system and method for drying sand

Abstract

This invention relates to the field of industrial sand drying and energy optimization control, and particularly to a green production quality control system and method for drying sand. It includes: real-time monitoring and acquisition of sand data and drying environment data; preprocessing the acquired sand data and drying environment data to obtain preprocessed sand data and drying environment data; calculating the heat demand using a heat demand estimation and control algorithm, and dynamically correcting for heat loss; dynamically adjusting the heating power output based on the heat demand using an adaptive nonlinear heating power control algorithm; and calculating the heat recovery efficiency in the exhaust gas in real time at each moment using an instantaneous heat recovery efficiency calculation algorithm based on the heat demand and heating power output. This solves the technical problem that heat loss during the drying process is inevitably caused by conduction, convection, and radiation, and the heat loss decays exponentially over time, affecting drying efficiency and energy consumption.

Description

Technical Field

[0001] The invention relates to the field of industrial sand material drying and energy optimization control, and in particular to a green production quality control system and method for drying sand. Background Art

[0002] Dried sand is a natural sand and gravel material that has been washed and dried. It is widely used in many industries such as construction, casting, petrochemicals, glass, etc. The traditional production process of dried sand mainly includes sand screening, washing, dehydration and drying. With the growth of demand for sand and gravel materials in industry and the increase in resource consumption, the production and processing of sand requires higher efficiency while meeting environmental protection requirements.

[0003] However, there are many problems in the traditional drying sand production process, such as high energy consumption, serious exhaust gas and dust emissions, water resource waste, and unstable quality control during the production process. In particular, the drying process consumes a lot of energy and relies on fossil fuels such as coal, natural gas and diesel, producing a large amount of carbon dioxide and pollutants. In addition, the control of production quality relies on experience and judgment, lacks automated and intelligent monitoring methods, and easily leads to product quality fluctuations; at the same time, in the sand drying process, heat is inevitably lost due to conduction, convection and radiation, and the heat loss will decay exponentially over time. If it is not corrected, it may cause the system to have excessive or insufficient heat supply in the subsequent stage, thereby affecting the drying efficiency and energy consumption; and the reduction of sand humidity will affect the dynamic changes in heat demand. Too high or too low humidity will lead to increased energy consumption or insufficient drying. Therefore, realizing the greening, intelligence and high-quality control of the sand drying process has become an important direction for the development of the industry, and a green production quality control system and method for drying sand has emerged. Summary of the invention

[0004] The present invention provides a green production quality control system and method for drying sand, so as to solve the problem of accurate calculation of heat demand in the process of sand material drying; and the inevitable loss of heat due to conduction, convection and radiation in the drying process, and the heat loss will decay exponentially with time. If it is not corrected, it may cause the system to have excess or insufficient heat supply in the subsequent stage, affecting the drying efficiency and energy consumption; the reduction of sand material humidity will affect the dynamic change of heat demand, and too high or too low humidity will lead to increased energy consumption or insufficient drying; heating power output adaptive control and power overload protection; real-time control of exhaust gas heat recovery efficiency.

[0005] A drying sand green production quality control system and method of the present invention specifically includes the following technical solutions:

[0006] A method for controlling the green production quality of dried sand comprises the following steps:

[0007] S1: real-time monitoring and acquisition of abrasive material data and drying environment data, preprocessing the acquired abrasive material data and drying environment data to obtain preprocessed abrasive material data and drying environment data; based on the preprocessed abrasive material data and drying environment data, using a heat demand estimation and control algorithm to calculate the heat demand, and dynamically correct the heat loss;

[0008] S2: Based on the heat demand, the heating power output is dynamically adjusted through an adaptive nonlinear heating power control algorithm;

[0009] S3: Based on the heat demand and heating power output, the instantaneous heat recovery efficiency calculation algorithm is used to calculate the heat recovery efficiency in the exhaust gas at each moment in real time to adjust the heating power output.

[0010] Preferably, the S1 specifically includes:

[0011] The pretreated sand material data and drying environment data include the pretreated sand material particle diameter, the pretreated sand material temperature, the pretreated sand material flow rate, the pretreated air flow rate and the pretreated sand material humidity; the heat demand estimation and control algorithm calculates the specific surface area according to the density of the sand material particles and the pretreated sand material particle diameter, and combines the square term of the pretreated sand material particle diameter and the sand material particle surface roughness coefficient to simulate the influence of different sand material particle surface characteristics on heat transfer.

[0012] Preferably, the S1 specifically includes:

[0013] During the drying process, the temperature of the pretreated sand and the energy required for evaporating water are calculated according to the specific heat capacity of the sand and the latent heat of vaporization of water. The exponential decay term of heat loss is introduced to correct the heat loss caused by heat dissipation and conduction during the drying process. The heat demand is corrected by the ratio between the pretreated air flow rate and the pretreated sand flow rate. The heat demand calculation formula is:

[0014] ,

[0015] in, Indicates at time caloric needs; Indicates the specific heat capacity of sand; Indicates at time Sand temperature after pretreatment; represents the latent heat of vaporization of water; An exponential decay term representing heat loss; represents the heat loss coefficient; It indicates the ratio of the air flow rate after pretreatment to the sand flow rate after pretreatment; Indicates the air flow rate after pretreatment; Indicates the flow rate of the sand after pretreatment; Indicates the time rate of change of the moisture content of the pretreated sand; Indicates at time Moisture content of sand after pretreatment; It indicates the correction factor of heat absorption of the pre-treated sand particle size.

[0016] Preferably, the S2 specifically includes:

[0017] In the implementation of the adaptive nonlinear heating power control algorithm, the power adjustment coefficient is introduced to convert the calculated heat demand into heating power output and calculate the moisture deviation of the pretreated sand.

[0018] Preferably, the S2 specifically includes:

[0019] In the process of implementing the adaptive nonlinear heating power control algorithm, a temperature dynamic adjustment item is introduced to simulate the influence of ambient temperature fluctuation on heat demand through the temperature adjustment factor, and the frequency of temperature difference response is controlled through the temperature adjustment frequency parameter.

[0020] Preferably, the S2 specifically includes:

[0021] In the implementation process of the adaptive nonlinear heating power control algorithm, the heating power output is calculated based on power adjustment, humidity deviation, temperature regulation and heat recovery efficiency; the specific calculation formula is:

[0022] ,

[0023] in, Indicates at time Heating power output; Indicates taking the minimum value; Indicates the maximum power limit of the heating power output; Indicates the power adjustment factor; Indicates at time caloric needs; represents the dynamic adjustment coefficient; Indicates the moisture deviation of the sand after pretreatment; Indicates the temperature dynamic adjustment item; Indicates the temperature adjustment frequency parameter; Indicates the current sand temperature after pretreatment and ambient temperature The standardized temperature difference represents the time integral of the heat recovery efficiency; Indicates a time interval; represents the time variable; Indicates at time heat recovery efficiency.

[0024] Preferably, the S3 specifically includes:

[0025] The instantaneous heat recovery efficiency calculation algorithm collects sensor data in the production environment in real time through sensors, quantifies the instantaneous recoverable energy in the exhaust gas, and calculates the heat recovery efficiency in combination with the instantaneous heat demand of the drying sand.

[0026] Preferably, the S3 specifically includes:

[0027] In the process of implementing the instantaneous heat recovery efficiency calculation algorithm, the heating power output value at the current moment is obtained, and the humidity coupling coefficient is introduced to calculate the actual impact of humidity on the heat recovery efficiency; the calculation formula for the heat recovery efficiency is:

[0028] ,

[0029] in, Indicates the heat recovery efficiency; Indicates at time Heating power output; Indicates at time caloric needs; Indicates the correction factor for heat loss; represents the heat loss constant; represents the temperature scaling factor; Indicates at time The exhaust gas outlet temperature; Indicates at time The incoming air temperature; represents the humidity coupling coefficient; Indicates exhaust gas humidity; Represents the temperature sinusoidal function correction term.

[0030] A green production quality control system for dried sand, including the following parts:

[0031] Data acquisition module, data preprocessing module, heat demand estimation module, power control module, heat recovery efficiency calculation module;

[0032] Data acquisition module: real-time monitoring and acquisition of sand material data and drying environment data, and output of the sand material data and drying environment data to the data preprocessing module;

[0033] Data preprocessing module: preprocess the acquired sand material data and drying environment data to obtain preprocessed sand material data and drying environment data, and output the preprocessed sand material data and drying environment data to the heat demand estimation module;

[0034] Heat demand estimation module: receives the pre-processed sand material data and drying environment data from the data pre-processing module, calculates the heat demand using the heat demand estimation and control algorithm, and outputs the heat demand to the power control module and the heat recovery efficiency calculation module;

[0035] Power control module: receiving the heat demand from the heat demand estimation module and the heat recovery efficiency from the heat recovery efficiency calculation module, dynamically adjusting the heating power output through an adaptive nonlinear heating power control algorithm, and outputting the heating power output to the heat recovery efficiency calculation module;

[0036] Heat recovery efficiency calculation module: Based on the heat demand of the heat demand estimation module and the heating power output of the power control module, the instantaneous heat recovery efficiency calculation algorithm is used to calculate the heat recovery efficiency in the exhaust gas at each moment in real time, and the heat recovery efficiency is output to the power control module.

[0037] The beneficial effects of the technical solution of the present invention are:

[0038] 1. Through the sensor network, key parameters such as sand particle diameter, temperature, humidity, air and sand flow rate are monitored in real time and pre-processed. The heat demand estimation and control algorithm is further used to comprehensively calculate the heat demand, accurately identify and dynamically correct the actual heat demand required by the sand during the drying process, and significantly reduce the deviation between heat supply and actual demand, so that the heating power can accurately meet the drying needs of the sand, thereby improving energy utilization efficiency and reducing unnecessary energy consumption.

[0039] 2. The correction coefficient of heat absorption of the pre-treated sand particle size is used to dynamically adjust the contribution of different particles to heat absorption through the logarithmic terms of specific surface area, diameter ratio and square correction, ensuring that the relative contribution of different particle sizes in the heat absorption process is reasonable, avoiding the excessive influence of large particles, and ensuring that the heat absorption effect of small particles is enhanced. The dynamic correction mechanism of particle size greatly improves the uniformity of heat distribution, improves the uniformity and stability of overall drying, and ensures the final drying quality of the sand.

[0040] 3. The exponential decay term of heat loss is introduced to correct the heat loss caused by heat dissipation and conduction, and the heat transfer efficiency is improved by dynamically calculating the ratio of the pre-treated air flow rate to the pre-treated sand flow rate; as the flow rate changes, the heat demand can be adjusted in real time to reduce heat waste, which not only reduces heat loss, but also ensures that the drying process can respond flexibly under changing flow rate conditions, improves the overall energy utilization efficiency, and reduces environmental heat loss.

[0041] 4. Through the adaptive nonlinear heating power control algorithm, the heating power output is dynamically adjusted based on the real-time calculated heat demand and humidity deviation to match the heat supply with the demand. The temperature dynamic adjustment item further smoothes the power demand impact caused by ambient temperature fluctuations. The real-time feedback of energy recovery efficiency ensures the rationality of the heating power output and realizes the precise control of the heating power output of the drying equipment. While improving the drying quality, it avoids power overload and unnecessary equipment wear, and improves the overall stability and service life of the system.

[0042] 5. Through the instantaneous heat recovery efficiency calculation algorithm, the recoverable heat in the exhaust gas at each moment is calculated in real time, and factors such as the temperature difference in the heat transfer device, the humidity coupling coefficient and the temperature proportional factor are included in the calculation, so that the system can recover the heat in the exhaust gas in real time and feedback control the heating power output, optimize the utilization rate of the residual heat in the exhaust gas, improve the overall energy recovery efficiency of the system, realize the recycling of thermal energy, reduce the total energy consumption, and achieve the purpose of energy saving and consumption reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is a structural diagram of a green production quality control system for drying sand according to the present invention;

[0044] Figure 2 This is a flow chart of the green production quality control method of dried sand described in the present invention. DETAILED DESCRIPTION

[0045] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only a part of the embodiment of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0047] The specific scheme of a drying sand green production quality control system and method provided by the present invention is described in detail below in conjunction with the accompanying drawings.

[0048] Refer to the attached Figure 1 , which shows a structural diagram of a drying sand green production quality control system provided by an embodiment of the present invention, the system includes the following parts:

[0049] Data acquisition module, data preprocessing module, heat demand estimation module, power control module, heat recovery efficiency calculation module;

[0050] Data acquisition module: Arrange sensor network to monitor and obtain sand material data and drying environment data in real time, such as sand material particle diameter, sand material temperature, sand material flow rate, air flow rate, sand material humidity, and output the sand material data and drying environment data to the data preprocessing module;

[0051] Data preprocessing module: preprocess the acquired sand material data and drying environment data to obtain preprocessed sand material data and drying environment data, and output the preprocessed sand material data and drying environment data to the heat demand estimation module;

[0052] Heat demand estimation module: receives the pre-processed sand material data and drying environment data from the data pre-processing module, calculates the heat demand using the heat demand estimation and control algorithm, and outputs the heat demand to the power control module and the heat recovery efficiency calculation module;

[0053] Power control module: receiving the heat demand from the heat demand estimation module and the heat recovery efficiency from the heat recovery efficiency calculation module, dynamically adjusting the output of the heating power through an adaptive nonlinear heating power control algorithm, and outputting the output of the heating power to the heat recovery efficiency calculation module;

[0054] Heat recovery efficiency calculation module: Based on the heat demand of the heat demand estimation module and the heating power output of the power control module, the instantaneous heat recovery efficiency calculation algorithm is used to calculate the heat recovery efficiency in the exhaust gas at each moment in real time, and the heat recovery efficiency is output to the power control module.

[0055] Refer to the attached Figure 2 , which shows a flow chart of a method for controlling the quality of green production of dried sand provided by an embodiment of the present invention, the method comprising the following steps:

[0056] S1. Real-time monitoring and acquisition of sand material data and drying environment data, preprocessing the acquired sand material data and drying environment data to obtain preprocessed sand material data and drying environment data; based on the preprocessed sand material data and drying environment data, using a heat demand estimation and control algorithm to calculate the heat demand, and dynamically correct the heat loss;

[0057] Arrange a sensor network to monitor and obtain sand material data and drying environment data in real time, such as sand material particle diameter, sand material temperature, sand material flow rate, air flow rate, and sand material humidity; pre-process the obtained sand material data and drying environment data to obtain pre-processed sand material data and drying environment data; the pre-processing method is a technical means well known to those skilled in the art and will not be described in detail here;

[0058] In order to ensure that the heating power in the drying equipment accurately matches the actual demand of the abrasive, a heat demand estimation and control algorithm is used to calculate the heat demand based on the pre-treated abrasive particle diameter, abrasive temperature, abrasive humidity, air flow rate and abrasive flow rate, and dynamically correct the heat loss;

[0059] Specifically, the diameter of each sand particle will directly affect the specific surface area and heat absorption efficiency. The specific surface area is the ratio of the surface area of ​​the particle to the mass. The larger the specific surface area, the higher the efficiency of the particle in absorbing heat. The specific surface area needs to be calculated based on the density of each sand particle and the diameter of the sand particle after pretreatment. The logarithm of the ratio of the maximum sand particle diameter to the current sand particle diameter after pretreatment is also used to amplify the relative contribution of very small particles in absorbing heat, while avoiding excessive amplification of the influence of very large particles. Through the square term, it can be ensured that as the sand particles increase, the correction coefficient of the pretreated sand particle size for heat absorption decreases rapidly, avoiding that large particles account for too high a proportion of the total heat demand, and using the sand particle surface roughness coefficient for compensation to simulate the influence of different particle surface characteristics on heat transfer;

[0060] During the drying process, the sand material needs to absorb a certain amount of heat to reach the required temperature, and also needs enough energy to evaporate the water. The heat demand needs to consider two parts, one is the energy used to increase the temperature of the pretreated sand material, and the other is the energy used for water evaporation; the energy required to increase the temperature of the pretreated sand material is calculated based on the specific heat capacity of the sand material and the current temperature of the pretreated sand material, and then the energy required to evaporate the water is calculated based on the latent heat of vaporization of water;

[0061] In the drying process, heat will inevitably be lost due to conduction, convection and radiation. In order to reduce the error, the exponential decay term of heat loss is introduced to correct the heat loss caused by heat dissipation and conduction in the drying process. As time goes by, the transferred heat gradually decreases;

[0062] The flow rates of air and abrasive materials also have an important influence on the heat transfer process. By real-time monitoring the ratio between the pre-treated air flow rate and the pre-treated abrasive material flow rate, and correcting the heat demand according to the ratio, if the pre-treated air flow rate is fast, the heat transfer efficiency is accelerated; on the contrary, if the pre-treated abrasive material flow rate is fast, the residence time of the abrasive material in the drying equipment is shortened, which will also affect the heat demand. The ratio of the pre-treated air flow rate to the pre-treated abrasive material flow rate is used as a key variable in the dynamic calculation and adjusted in real time.

[0063] According to the real-time sand material humidity data after pretreatment, the change rate of the pretreated sand material humidity over time is calculated, which can reflect the speed of sand material dehydration during the drying process, which will directly affect the heat demand;

[0064] The formula for calculating caloric requirements is:

[0065] ,

[0066] in, Indicates at time caloric needs; It indicates the specific heat capacity of the sand, reflecting the amount of heat that the sand needs to absorb for every 1K (Kelvin) increase in temperature; Indicates at time Sand temperature after pretreatment; It represents the latent heat of vaporization of water, which describes the heat required for the water in the sand to transform from liquid to gas during the drying process; The exponential decay term representing heat loss is used to correct the heat loss caused by heat dissipation and conduction during the drying process; It represents the heat loss coefficient, which reflects the loss rate of heat during the transfer process; It indicates the ratio of the air flow rate after pretreatment to the sand flow rate after pretreatment, reflecting the heat transfer efficiency of the air flow after pretreatment to the sand. The faster the air flow rate after pretreatment, the higher the heat transfer efficiency relative to the sand. Indicates the air flow rate after pretreatment; Indicates the flow rate of the sand after pretreatment; It indicates the time change rate of the moisture content of the pretreated sand material, reflects the rate of change of the moisture content of the pretreated sand material, and determines the dynamic process of water evaporation during the drying process; Indicates at time Moisture content of sand after pretreatment; It indicates the correction coefficient of the particle size of the pre-treated sand material on the heat absorption, which is used to reflect the influence of the particle size of the pre-treated sand material on the heat absorption. The specific calculation formula is:

[0067] ,

[0068] in, Indicates The diameter of sand particles after pretreatment; It represents the specific surface area of ​​the sand particles after pretreatment. , Indicates the density of the sand. The larger the specific surface area, the more area the sand particles are in contact with the heat flow, and the stronger the heat absorption capacity; It represents the natural logarithmic function, which helps to smooth the effect of the particle size of sand material after different pretreatments on heat absorption, so that the difference in heat absorption capacity between large and small particle sizes can be reasonably expressed; Represents the maximum particle diameter after pretreatment, used for normalization calculation; It indicates the surface roughness coefficient of sand particles. The rougher the particle surface, the more heat it absorbs. It corrects the influence of surface characteristics of different particles on heat absorption performance. Indicates The square term of the diameter of the pretreated sand particles can ensure that as the particles increase, the correction factor of the particle size for heat absorption will decrease rapidly, avoiding that large particles account for too high a proportion of the total heat demand.

[0069] S2, dynamically adjust the heating power output based on the heat demand through an adaptive nonlinear heating power control algorithm;

[0070] Dynamically adjust the heating power output through adaptive nonlinear heating power control algorithm to ensure that the heat supply matches the actual demand and optimize energy efficiency;

[0071] The adaptive nonlinear heating power control algorithm calculates the corresponding heating power output according to the heat demand, introduces the power adjustment coefficient, converts the calculated heat demand into an appropriate heating power output, and further calculates the humidity deviation after the current pretreatment, that is, the difference between the humidity of the sand material after the pretreatment and the preset target humidity. The target humidity is the humidity requirement for the final dried sand in the production process to ensure that the established drying quality standard is met;

[0072] Introduce a temperature dynamic adjustment item, and use the temperature adjustment factor calculated by the cosine function to simulate the impact of ambient temperature fluctuations on heat demand, so as to smooth the impact of temperature differences, and control the frequency of temperature difference response by adjusting the temperature frequency parameter;

[0073] By calculating the heat recovery efficiency over a period of time, it reflects the power consumption and recovered heat energy status in the previous period of time. As one of the bases for adjusting the current power, the changing trend of the heat recovery efficiency can be identified, thereby dynamically adjusting the heating power output and further optimizing the system energy consumption.

[0074] Combine the cumulative effects of power adjustment, humidity deviation, temperature regulation and heat recovery efficiency to determine the current actual heating power output, but at the same time ensure that the output power does not exceed the maximum power limit of the drying equipment, avoid failure or loss of the drying equipment due to power overload, and ensure control accuracy;

[0075] The calculation formula for heating power output is:

[0076] ,

[0077] in, Indicates at time Heating power output; Indicates taking the minimum value; Indicates the maximum power limit of the heating power output, ensuring that the heating power output does not exceed the safety limit of the drying equipment to prevent power overload, which is determined by the physical limitations and design safety standards of the drying equipment; represents the power adjustment factor, which converts the calculated heat demand into the appropriate heating power output; Indicates at time caloric needs; Indicates the dynamic adjustment coefficient, which is used to fine-tune the heating power output; Indicates the humidity deviation of the sand after pretreatment, which indicates the difference between the current humidity and the target humidity. It is used to determine the humidity requirement during the drying process and ensure that the heating power output adapts to the real-time humidity changes. It represents the temperature dynamic adjustment item, which is the temperature adjustment factor calculated by the cosine function, simulating the effect of ambient temperature fluctuation on heat demand to smooth the effect of temperature difference; Represents the temperature adjustment frequency parameter, which is used to control the frequency of temperature difference response; Indicates the current sand temperature after pretreatment and ambient temperature The standardized temperature difference Represents the time integral of heat recovery efficiency, which is used to smooth the change of heat recovery efficiency and optimize the matching between heating power output and recovered energy; Represents a time interval used to continuously quantify the heat recovery efficiency; represents the time variable; Indicates at time heat recovery efficiency.

[0078] S3, based on the heat demand and the heating power output, using the instantaneous heat recovery efficiency calculation algorithm to calculate the heat recovery efficiency in the exhaust gas at each moment in real time to adjust the heating power output;

[0079] In the heat recovery process, in order to achieve the instantaneous heat recovery mode, the instantaneous heat recovery efficiency calculation algorithm is required to calculate the heat recovery efficiency in the exhaust gas at each moment in real time to ensure that the heat in the exhaust gas can be directly fed back to the power control, thereby accurately adjusting the heating power output of the entire drying sand green production quality control system;

[0080] The instantaneous heat recovery efficiency calculation algorithm collects sensor data in the production environment in real time through sensors, such as temperature and humidity sensors and flow rate sensors, including exhaust gas temperature, air humidity, inlet and outlet temperature difference, and exhaust gas humidity, aiming to quantify the instantaneous recoverable energy in the exhaust gas, and calculate the heat recovery efficiency in combination with the instantaneous heat demand of the drying sand, including the energy transferred from the exhaust gas to the incoming air in the multi-stage heat transferer and the influence of the exhaust gas humidity on the heat recovery;

[0081] The power output value at the current moment is obtained as the initial power benchmark for exhaust gas heat recovery. A correction factor for describing heat loss is applied so that the recoverable heat in the exhaust gas decays exponentially over time during the heat transfer process, which can accurately reflect the heat loss of the exhaust gas during the heat transfer process.

[0082] Calculate the ratio of the exhaust gas temperature to the incoming air temperature to determine the heat transfer efficiency. The ratio indicates the temperature difference of the exhaust gas when transferring heat. The temperature difference affects the heat transfer efficiency. The greater the temperature difference, the more heat can be recovered from the exhaust gas. The smaller the temperature difference, the lower the heat transfer efficiency.

[0083] Since humidity has a significant impact on heat transfer, the role of exhaust gas humidity in heat recovery needs to be considered. The relationship between the exhaust gas humidity value and the ambient temperature is processed through the preset humidity coupling coefficient, and the actual impact of humidity on heat recovery efficiency is calculated; the ratio of ambient temperature to the temperature of the pretreated sand is used as a dynamic response factor to control the heating efficiency of the drying sand green production quality control system under different environmental conditions;

[0084] A humidity coupling coefficient proportional to the exhaust gas humidity is introduced to adjust the effect of humidity on instantaneous heat recovery. The higher the humidity, the more obvious the effect of the humidity coupling coefficient on the heat recovery efficiency.

[0085] The calculation formula for heat recovery efficiency is:

[0086] ,

[0087] in, Indicates the heat recovery efficiency, that is, The ratio of heat recovered to heat demand; Indicates at time Heating power output; Indicates at time caloric needs; It indicates the correction factor of heat loss, which is used to reflect the loss of exhaust gas heat during the heat transfer process; Represents the heat loss constant, which is used to describe the heat transfer efficiency of the heat transfer device (related to the material and thermal resistance); Indicates the temperature proportional factor, which is used to reflect the instantaneous ratio of the exhaust gas temperature to the incoming air temperature, and affects the dynamic changes of the instantaneous heat recovery efficiency; Indicates at time The exhaust gas outlet temperature, that is, the temperature of the exhaust gas when it leaves the heat transfer device; Indicates at time The incoming air temperature is the temperature of the new air entering the heat exchanger; Represents the humidity coupling coefficient, which is used to adjust the effect of humidity on instantaneous heat recovery; Indicates exhaust gas humidity; represents the temperature sine function correction term, which is a sine function based on the ratio of the ambient temperature to the pre-treated sand temperature;

[0088] The heat recovery efficiency is the actual reflection of the recoverable heat in the exhaust gas, which provides a feedback reference for the real-time power adjustment of the drying sand green production quality control system, thereby ensuring that the heat in the exhaust gas can be recovered and utilized to the greatest extent and fed back to the drying sand green production quality control system to achieve higher overall energy efficiency.

[0089] In summary, a green production quality control system and method for dried sand is completed.

[0090] The order of the embodiments of the invention is for description only and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0091] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0092] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention.

Claims

1. A method for controlling the green production quality of dried sand, characterized in that: The following steps are involved: S1: real-time monitoring and acquisition of sand material data and drying environment data, preprocessing the acquired sand material data and drying environment data to obtain preprocessed sand material data and drying environment data; The pre-treated sand material data and drying environment data include the pre-treated sand material particle diameter, the pre-treated sand material temperature, the pre-treated sand material flow rate, the pre-treated air flow rate and the pre-treated sand material humidity; Based on the pre-treated sand material data and the drying environment data, a heat demand estimation and control algorithm is used to calculate the heat demand and dynamically correct the heat loss; the heat demand estimation and control algorithm calculates the specific surface area according to the density of the sand material particles and the diameter of the pre-treated sand material particles, and combines the square term of the pre-treated sand material particle diameter and the surface roughness coefficient of the sand material particles to simulate the influence of different sand material particle surface characteristics on heat transfer; During the drying process, the temperature of the pretreated sand and the energy required for evaporating water are calculated according to the specific heat capacity of the sand and the latent heat of vaporization of water. The exponential decay term of heat loss is introduced to correct the heat loss caused by heat dissipation and conduction during the drying process. The heat demand is corrected by the ratio between the pretreated air flow rate and the pretreated sand flow rate. The heat demand calculation formula is: ， in, Indicates at time caloric needs; Indicates the specific heat capacity of sand; Indicates at time Sand temperature after pretreatment; represents the latent heat of vaporization of water; An exponential decay term representing heat loss; represents the heat loss coefficient; It indicates the ratio of the air flow rate after pretreatment to the sand flow rate after pretreatment; Indicates the air flow rate after pretreatment; Indicates the flow rate of the sand after pretreatment; Indicates the time rate of change of the moisture content of the pretreated sand; Indicates at time Moisture content of sand after pretreatment; It indicates the correction factor of heat absorption by the particle size of the pre-treated sand material; S2: Based on the heat demand, the heating power output is dynamically adjusted through an adaptive nonlinear heating power control algorithm; In the process of implementing the adaptive nonlinear heating power control algorithm, the power adjustment coefficient is introduced to convert the calculated heat demand into heating power output and calculate the moisture deviation of the pre-treated sand material; Introduce dynamic temperature adjustment items to simulate the impact of ambient temperature fluctuations on heat demand through temperature adjustment factors, and control the frequency of temperature difference response through temperature adjustment frequency parameters; The heating power output is calculated based on power adjustment, humidity deviation, temperature regulation and heat recovery efficiency; the specific calculation formula is: ， in, Indicates at time Heating power output; Indicates taking the minimum value; Indicates the maximum power limit of the heating power output; Indicates the power adjustment factor; Indicates at time caloric needs; represents the dynamic adjustment coefficient; Indicates the moisture deviation of the sand after pretreatment; Indicates the temperature dynamic adjustment item; Indicates the temperature adjustment frequency parameter; Indicates the current sand temperature after pretreatment and ambient temperature The standardized temperature difference represents the time integral of the heat recovery efficiency; Indicates a time interval; represents the time variable; Indicates at time Heat recovery efficiency; S3: Based on the heat demand and heating power output, the instantaneous heat recovery efficiency calculation algorithm is used to calculate the heat recovery efficiency in the exhaust gas at each moment in real time to adjust the heating power output.

2. A method for controlling green production quality of drying sand according to claim 1, characterized in that, The S3 specifically includes: The instantaneous heat recovery efficiency calculation algorithm collects sensor data in the production environment in real time through sensors, quantifies the instantaneous recoverable energy in the exhaust gas, and calculates the heat recovery efficiency in combination with the instantaneous heat demand of the drying sand.

3. A method for controlling green production quality of drying sand according to claim 2, characterized in that, The S3 specifically includes: In the process of implementing the instantaneous heat recovery efficiency calculation algorithm, the heating power output value at the current moment is obtained, and the humidity coupling coefficient is introduced to calculate the actual impact of humidity on the heat recovery efficiency; the calculation formula for the heat recovery efficiency is: ， in, Indicates the heat recovery efficiency; Indicates at time Heating power output; Indicates at time caloric needs; Indicates the correction factor for heat loss; represents the heat loss constant; represents the temperature scaling factor; Indicates at time The exhaust gas outlet temperature; Indicates at time The incoming air temperature; represents the humidity coupling coefficient; Indicates exhaust gas humidity; Represents the temperature sinusoidal function correction term.

4. A green production quality control system for dried sand, applied to the green production quality control method for dried sand according to claim 1, characterized in that: Includes the following sections: Data acquisition module, data preprocessing module, heat demand estimation module, power control module, heat recovery efficiency calculation module; Data acquisition module: real-time monitoring and acquisition of sand material data and drying environment data, and output of the sand material data and drying environment data to the data preprocessing module; Data preprocessing module: preprocess the acquired sand material data and drying environment data to obtain preprocessed sand material data and drying environment data, and output the preprocessed sand material data and drying environment data to the heat demand estimation module; Heat demand estimation module: receives the pre-processed sand material data and drying environment data from the data pre-processing module, calculates the heat demand using the heat demand estimation and control algorithm, and outputs the heat demand to the power control module and the heat recovery efficiency calculation module; Power control module: receiving the heat demand from the heat demand estimation module and the heat recovery efficiency from the heat recovery efficiency calculation module, dynamically adjusting the heating power output through an adaptive nonlinear heating power control algorithm, and outputting the heating power output to the heat recovery efficiency calculation module; Heat recovery efficiency calculation module: Based on the heat demand of the heat demand estimation module and the heating power output of the power control module, the instantaneous heat recovery efficiency calculation algorithm is used to calculate the heat recovery efficiency in the exhaust gas at each moment in real time, and the heat recovery efficiency is output to the power control module.

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