An adaptive water adding control method for a laboratory slag soil baking-free brick preparation process

Abstract

This invention discloses an adaptive water addition control method for the preparation process of laboratory-grade non-fired bricks from slag, relating to the fields of solid waste resource utilization and building material preparation technology. The method includes: obtaining the total mass and initial moisture content of the raw materials and calculating the theoretical water addition amount; calculating the initial empirical compensation amount based on raw material characteristic parameters, environmental evaporation parameters, and process loss parameters, and obtaining the final empirical compensation amount through boundary limiting; determining the total target water addition amount and the initial pre-added water amount based on the theoretical water addition amount and the final empirical compensation amount; real-time monitoring of the actual moisture content of the mixture during stirring, calculating the water replenishment increment based on its deviation from the target moisture content, and performing water replenishment after non-negativity, dead zone judgment, and single-time water replenishment limiting until the moisture content is within the allowable error range; and recording the water addition control process data. This invention can improve the accuracy of endpoint moisture content control and the traceability of batch data.

Description

Technical Field

[0001] This application relates to the fields of solid waste resource utilization and building material preparation technology, specifically, to an adaptive water addition control method for the preparation process of laboratory slag non-fired bricks. Background Technology

[0002] Currently, the resource utilization of solid waste such as construction slag and tunnel boring machine sludge to produce non-fired bricks is an important direction for the high-value utilization of construction solid waste. In the laboratory research and development stage, numerous small-batch, multi-formulation experiments are typically conducted, focusing on different sources of slag, the dosage of cementitious materials, the type of admixtures, and the molding pressure. Among these, the moisture content of the mixture directly affects the uniformity of material mixing, the stability of brick molding, the integrity of demolding, and subsequent strength development, making it a key process parameter that needs to be carefully controlled in the preparation of slag-based non-fired bricks. However, the following technical challenges still exist in the current laboratory experimental research stage: In current laboratory-scale preparation processes for non-fired bricks from slag, the amount of water added is typically determined manually based on experience or a fixed ratio. Researchers generally need to first sample and dry the raw materials to determine the initial moisture content, and then manually calculate and weigh the amount of water to add according to the target formula. This method is cumbersome, time-consuming, and fails to reflect the effects of uneven moisture content within the same batch of slag, differences in water absorption capacity among different slag types, and changes in environmental temperature and humidity. This can easily lead to the mixture being too dry or too wet, resulting in problems such as corner chipping, sticking to the mold, edge collapse, or fluctuations in density of the bricks.

[0003] While existing non-fired brick or brick-making equipment can achieve a certain degree of automation in batching, mixing, and pressing, its water control mostly relies on preset water addition, fixed water-to-material ratios, or simple program control, primarily suitable for continuous production scenarios where raw material properties are relatively stable. However, in laboratory research conditions involving small batches, multiple formulations, and significant raw material fluctuations, the initial moisture content, particle composition, clay mineral content, and water retention characteristics of the slag soil frequently change. If the equipment cannot dynamically adjust the water addition based on the real-time state of the raw materials and environmental conditions, it becomes difficult to guarantee the consistency of moisture content and the comparability of formulations between different batches of tests.

[0004] There is currently no effective solution to the above problems. Summary of the Invention

[0005] This application provides an adaptive water addition control method for the preparation process of laboratory slag non-fired bricks to solve the above-mentioned technical problems.

[0006] This application provides an adaptive water addition control method for the preparation process of laboratory-grade non-fired bricks from slag, comprising: obtaining the total mass and initial moisture content of the raw materials; calculating the dry weight of the raw materials based on the total mass and initial moisture content; calculating the theoretical water addition amount based on the dry weight of the raw materials, the target moisture content, and the initial moisture content; calculating the initial empirical compensation amount without boundary treatment based on raw material characteristic parameters, environmental evaporation parameters, and process loss parameters; performing boundary limiting treatment on the initial empirical compensation amount to obtain the final empirical compensation amount; and calculating the total target water addition amount based on the theoretical water addition amount and the final empirical compensation amount; and calculating the total target water addition amount based on the total... The target water addition amount determines the initial pre-added water amount, and the water addition execution unit is controlled to output the initial pre-added water amount to the stirring unit. When the stirring unit stirs the mixture, the online humidity detection unit is controlled to detect the actual moisture content of the mixture in real time. The water replenishment increment is calculated based on the deviation between the actual moisture content and the target moisture content, and the water addition execution unit is controlled to perform water replenishment until the deviation between the actual moisture content and the target moisture content is within the preset allowable error range. When the deviation between the actual moisture content and the target moisture content is within the preset allowable error range, the water addition control process data is recorded and stored.

[0007] Based on the embodiments provided in this application, the initial empirical compensation amount without boundary treatment is calculated according to the raw material characteristic parameters, environmental evaporation parameters, and process loss parameters. The initial empirical compensation amount is then subjected to boundary limiting treatment to determine the final empirical compensation amount. Combined with the theoretical water addition amount, the total target water addition amount is calculated. This allows the determination of the initial pre-added water amount to pre-compensate for the water absorption characteristics of the current batch of slag, the temperature and humidity of the laboratory environment, and the water loss during the mixing process. It also avoids the direct impact on the total target water addition amount caused by excessive or insufficient compensation amount due to raw material classification errors, abnormal environmental evaporation compensation coefficients, equipment calibration deviations, or detection errors. This avoids the problem that a single fixed water-material ratio or manual experience estimation is difficult to adapt to raw material fluctuations and environmental changes, and improves the pertinence of the initial water addition amount.

[0008] By controlling the online humidity detection unit to monitor the actual moisture content of the mixture in real time while the mixing unit is operating, and calculating the water replenishment increment based on the deviation between the actual moisture content and the target moisture content using incremental digital PID control parameters obtained through step water replenishment response test tuning or conversion of reference operating condition parameters, the water replenishment increment is processed by nonnegation, water replenishment dead zone judgment, and single water replenishment upper limit limit before water replenishment is executed. Then, the water replenishment execution unit is controlled to replenish water until the deviation is within the preset allowable error range. This achieves dynamic correction of moisture content during the mixing process, enabling timely correction of uneven moisture content, pre-watering deviation, or water absorption lag within the same batch of mixture. At the same time, it avoids control jitter or moisture content overshoot caused by negative water replenishment commands, invalid small pulse water replenishment, and excessive single water replenishment, reducing the quality defects of brick blanks caused by the mixture being too dry or too wet, and without interrupting the mixing or re-weighing.

[0009] By recording and storing the water addition control process data after the moisture content deviation reaches the standard, a complete process record is provided for laboratory multi-formulation, multi-batch experiments. This record includes the initial state of raw materials, theoretical water addition, empirical compensation, initial pre-water addition, PID water replenishment process, final stable moisture content, and drying verification results. This makes the water addition control process of different batches of mixtures traceable. The above data can be correlated with the molding parameters, curing parameters, and subsequent performance test results of the corresponding brick blanks. This facilitates the analysis of the impact of moisture content control on the dispersion of brick blank molding quality and strength, and provides data basis for subsequent correction of compensation parameters, PID parameter verification, and formulation optimization for batches of the same or similar raw materials. Attached Figure Description

[0010] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a flowchart of an optional adaptive water addition control method for the preparation process of laboratory slag non-fired bricks according to an embodiment of this application; Figure 2 This is a schematic diagram of an optional laboratory slag non-fired brick preparation method according to an embodiment of this application; Figure 3 This is a flowchart of an adaptive water addition control method for another optional laboratory slag non-fired brick preparation process according to an embodiment of this application; Figure 4 This is a schematic diagram of the change in moisture content of a mixture as a function of stirring time, according to an embodiment of this application. Figure 5 This is a schematic diagram comparing key parameters and effects of adaptive water filling control under different optional operating conditions according to an embodiment of this application.

[0011] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0012] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0013] According to one aspect of the embodiments of this application, such as Figure 1 As shown, this application provides an adaptive water addition control method for the preparation process of laboratory slag non-fired bricks, including: S101, Obtain the total mass and initial moisture content of the raw materials, and calculate the dry weight of the raw materials based on the total mass and initial moisture content; S102, calculate the theoretical water addition amount based on the dry weight of the raw material, the target moisture content, and the initial moisture content, and calculate the initial empirical compensation amount based on the raw material characteristic parameters, environmental evaporation parameters, and process loss parameters; perform boundary limiting processing on the initial empirical compensation amount to obtain the final empirical compensation amount; calculate the total target water addition amount based on the theoretical water addition amount and the final empirical compensation amount; The initial empirical compensation amount was not subject to boundary limiting processing.

[0014] S103, determine the initial pre-added water volume based on the total target water volume, and control the water addition execution unit to output the initial pre-added water volume to the stirring unit; S104, when the mixing unit is mixing the mixture, the online humidity detection unit is controlled to detect the actual moisture content of the mixture in real time; the water replenishment increment is calculated based on the deviation between the actual moisture content and the target moisture content, and the water addition execution unit is controlled to perform water replenishment until the deviation between the actual moisture content and the target moisture content is within the preset allowable error range; In some embodiments of this application, S104 specifically includes: when the stirring unit stirs the mixture, controlling the online humidity detection unit to detect the actual moisture content of the mixture in real time; calculating the water replenishment increment based on the deviation between the actual moisture content and the target moisture content using PID control parameters obtained by step water replenishment response test tuning or conversion of reference working condition parameters; performing non-negative processing on the water replenishment increment, water replenishment dead zone judgment and single water replenishment upper limit limit to obtain the actual water replenishment amount, and controlling the water replenishment execution unit to perform water replenishment according to the actual water replenishment amount until the deviation between the actual moisture content and the target moisture content is within the preset allowable error range; S105, when the deviation between the actual moisture content and the target moisture content is within the preset allowable error range, record and store the water addition control process data.

[0015] Even when moisture detection devices are installed, some solutions are mostly used for initial testing before water addition or for single-point testing, lacking online moisture content feedback and closed-loop adjustment mechanisms during the mixing process. When localized water absorption lag, agglomeration, adhesion to the drum wall, spray loss, or water evaporation occur during mixing, the system struggles to make timely micro-water replenishment corrections, still requiring manual observation and judgment. Furthermore, the lack of automatic correlation recording between water addition, real-time moisture content changes, environmental parameters, and subsequent brick performance data hinders the analysis of the impact of moisture content control on brick forming quality and strength properties.

[0016] Based on the embodiments provided in this application, an online humidity detection unit tracks the actual moisture content of the mixture in real time while the mixing unit is operating. The unit automatically calculates the water replenishment increment based on the deviation between the actual and target values, and controls the water addition execution unit to perform water replenishment until the deviation meets the preset allowable error range. This establishes a closed-loop adjustment mechanism that requires no manual intervention throughout the mixing process. This mechanism effectively addresses moisture content fluctuations caused by disturbances such as localized water absorption lag, agglomeration, adhesion to the barrel wall, spray loss, or water evaporation during mixing, achieving micro-level autonomous correction and avoiding the lag and inaccuracy associated with manual observation and judgment. Simultaneously, once the moisture content deviation reaches the target, the water addition control process data is automatically recorded and stored. This provides a traceable data foundation for the correlation analysis of water addition, moisture content changes, and subsequent brick forming quality and strength performance, facilitating process research and data management under laboratory conditions of multiple formulations and small-batch experiments.

[0017] Furthermore, the determination of the final empirical compensation amount includes: subjecting the initial empirical compensation amount to boundary limiting processing to obtain the final empirical compensation amount; wherein, the initial empirical compensation amount includes raw material characteristic compensation item, environmental evaporation compensation item, and process loss compensation item; The boundary limiting process includes: converting the initial experience compensation amount into a unit dry material experience compensation amount and comparing it with a preset lower limit and a preset upper limit; when the unit dry material experience compensation amount is lower than the preset lower limit, the unit dry material experience compensation amount is set as the preset lower limit; when the unit dry material experience compensation amount is higher than the preset upper limit, the unit dry material experience compensation amount is set as the preset upper limit; when the unit dry material experience compensation amount is neither lower than the preset lower limit nor higher than the preset upper limit, the unit dry material experience compensation amount remains unchanged. The final experience compensation amount is calculated based on the unit dry material experience compensation amount and the dry weight of the raw materials; Furthermore, the raw material characteristic compensation item is determined according to the type of slag raw material, which is classified according to one or more of the following three indicators: clay mineral content, methylene blue value, and water absorption rate per minute; When the classification of slag raw material types obtained by determining the clay mineral content, methylene blue value and one-minute water absorption rate are inconsistent, the one-minute water absorption rate shall be used as the priority criterion and combined with the methylene blue value for verification. When the water absorption rate per minute exceeds the preset high water absorption threshold, or the methylene blue value exceeds the preset high adsorption threshold, the raw material characteristic compensation item will be limited to the preset upper limit of raw material characteristic compensation, and the operator will be prompted to calibrate the raw material separately or adjust the initial pre-added water volume.

[0018] Furthermore, the environmental evaporation compensation term is determined based on the ambient temperature, ambient relative humidity, water vapor pressure difference, effective exposure time, and environmental evaporation compensation coefficient. The water vapor pressure difference is calculated based on the ambient temperature and relative humidity. The effective exposure time is determined based on the opening status of the mixing unit. Under open mixing conditions, the actual mixing time is taken. Under semi-open mixing conditions, the mixing time is taken from the initial pre-addition of water until the moisture content of the mixture meets the stability judgment condition. Under closed mixing conditions, the actual mixing time is calculated according to the sealing degree of the mixing unit, mixing speed, loading amount and material exposure status, based on a preset ratio of the actual mixing time. The preset ratio is preferably 0.2 to 0.6, or determined through an environmental evaporation calibration test.

[0019] The environmental evaporation compensation coefficient is obtained through environmental evaporation calibration tests.

[0020] When the environmental evaporation calibration test under the current ambient temperature and relative humidity conditions has not been completed, the initial reference value of the environmental evaporation compensation coefficient is determined by linear interpolation or bilinear interpolation based on the preset recommended matrix of environmental evaporation compensation coefficient. When both the initial reference value and the single-point calibration value exist, the single-point calibration value shall be used first.

[0021] Furthermore, the process loss compensation item is determined through equipment process calibration tests; Among them, the equipment process calibration test uses calibration materials and is carried out under equipment and process conditions corresponding to the actual brick making process. The calibration materials are dried standard quartz sand or pre-homogenized inert fine aggregate. During calibration, the calibration command for water addition is output. After stirring, the calibration material is collected and the effective water volume is measured. The loss compensation for a single process is calculated based on the calibration command for water addition, the effective water volume, and the environmental evaporation loss during the calibration process. Multiple parallel calibrations are performed under the same equipment operating conditions. When the relative deviation of the multiple calibration results exceeds the preset deviation threshold, recalibration is performed. The average value of the multiple calibration results is taken as the process loss compensation item under the equipment operating conditions. If the relative deviation of three parallel calibrations is >15%, the calibration is deemed to have failed. Three types of faults need to be checked in sequence: nozzle blockage, metering pump flow drift, and material adhering to the inner wall of the mixing tank. After the problems are resolved, parallel calibration is performed again.

[0022] When the process loss compensation item exceeds the preset abnormal range, check the liquid metering pump, pipeline, nozzle, mixing tank wall and discharge method, and recalibrate after maintenance; If the liquid metering pump, spray pipeline, nozzle, mixing tank, or mixing paddle is replaced, or if the actual loading volume, mixing speed, spraying method, or calibration conditions change, then recalibration should be performed.

[0023] When the unit dry material experience compensation is lower than the preset lower limit or higher than the preset upper limit, record the abnormal status and prompt for review. When any of the following situations occur, a prompt will be made to re-perform raw material classification testing, environmental evaporation compensation coefficient calibration, or equipment process calibration: multiple consecutive batches show that the unit dry material experience compensation amount is lower than the preset lower limit; multiple consecutive batches show that the unit dry material experience compensation amount is higher than the preset upper limit; the difference between the initial experience compensation amount and the final experience compensation amount is greater than the preset recalibration trigger threshold.

[0024] Furthermore, the initial pre-added water volume is determined based on the total target water addition volume, including: The initial pre-addition water ratio is adjusted according to the total target water addition amount, and the initial pre-addition water ratio decreases as the total target water addition amount decreases; the initial pre-addition water amount is determined by multiplying the adjusted initial pre-addition water ratio by the total target water addition amount.

[0025] Furthermore, the method also includes: The amount of water to be added in response to feedback is determined based on the total target amount of water to be added, and the initial amount of water to be added shall not exceed the difference between the total target amount of water to be added and the amount of water to be added in response to feedback. When the total target water addition is less than or equal to the feedback water replenishment reserve, or when the total target water addition is less than or equal to zero, the initial pre-added water amount is set to zero.

[0026] Furthermore, the calculation of the water replenishment increment adopts an incremental digital PID control algorithm, which calculates the water replenishment increment for the current sampling period based on the moisture content deviation at the current sampling time, the moisture content deviation at the previous sampling time, and the moisture content deviation at the two previous sampling times. The proportional, integral, and derivative coefficients of the incremental digital PID control algorithm are obtained through step water replenishment response testing; or... The proportional coefficient, integral coefficient, and derivative coefficient of the incremental digital PID control algorithm are obtained by converting the reference operating condition parameters. The proportional coefficient is calculated based on the control parameters under the reference operating condition, combined with the dry weight of the raw material, the target moisture content, and the stirring speed of the current batch.

[0027] Furthermore, the method also includes: processing the output boundary of the water replenishment increment, specifically including: The water replenishment increment is nonnegated to obtain the nonnegative water replenishment amount. When the water replenishment increment is less than zero, the nonnegative water replenishment amount is zero. When the water replenishment increment is greater than or equal to zero, the nonnegative water replenishment amount is equal to the water replenishment increment. When the non-negative water replenishment volume is less than or equal to the preset water replenishment dead zone, the actual water replenishment volume is zero. When the non-negative water replenishment amount is greater than the preset water replenishment dead zone and the non-negative water replenishment amount is less than or equal to the preset single water replenishment limit, the actual water replenishment amount is equal to the non-negative water replenishment amount. When the non-negative water replenishment amount exceeds the preset single water replenishment limit, the actual water replenishment amount is equal to the preset single water replenishment limit. The remaining water limit is added simultaneously when calculating the actual water replenishment amount each time. Actual water replenishment amount = min (single water replenishment limit, remaining water to be replenished in the current batch) to avoid over-flushing when replenishing water in a single operation with a small amount of water.

[0028] Furthermore, when the actual moisture content is higher than the upper limit of the target moisture content for multiple consecutive sampling cycles, and the number of consecutive sampling cycles required by the preset alarm conditions is reached, an alarm signal is issued and a prompt is made to add dry material or re-prepare the batch of mixture. When the actual moisture content is lower than the lower limit of the target moisture content, continue to calculate the water replenishment increment based on the deviation between the actual moisture content and the target moisture content and perform water replenishment. When the actual moisture content is higher than the upper limit of the target moisture content for multiple consecutive sampling cycles, but the number of consecutive sampling cycles required by the preset alarm condition is not reached, the water addition execution unit is controlled to stop adding water, and the stirring unit is controlled to continue stirring and homogenizing.

[0029] Furthermore, recording and storing water addition control process data includes: A unique batch number is generated for this batch of mixture. The total mass of raw materials, initial moisture content, target moisture content, raw material dry weight, theoretical water addition, raw material characteristic compensation item, environmental evaporation compensation item, process loss compensation item, total target water addition, initial pre-added water, actual moisture content at each sampling time, deviation, water replenishment increment, and water addition execution related data are associated and stored with the molding parameters, curing parameters, and subsequent performance test results of the corresponding batch of brick blanks. Based on the process data of multiple batches, parameter review records or correction suggestions are generated for the raw material characteristic compensation item, environmental evaporation compensation item, process loss compensation item, or control parameters. The correction suggestions are used for operators to review the raw material characteristic compensation item, environmental evaporation compensation item, process loss compensation item, or control parameters.

[0030] The purpose of this invention is to address the problems encountered in the preparation of laboratory-made non-fired bricks from slag, such as complex raw material sources, large fluctuations in initial moisture content, difficulty in accurately controlling water addition manually or at fixed ratios, and lack of real-time correction during mixing. This invention provides an adaptive water addition control method suitable for small-batch, multi-formula laboratory experiments. This method combines rapid detection of initial raw material moisture content, calculation of target moisture content, correction using an empirical compensation model, and online humidity feedback adjustment. It achieves feedforward prediction and closed-loop fine-tuning of water addition to the brick-making mixture, ensuring that the actual moisture content of the mixture is stably close to the target moisture content. This improves the stability of brick forming, reduces errors in different batches of experiments, and provides a reliable foundation for data correlation and formula optimization between subsequent process parameters and brick performance.

[0031] This invention provides an adaptive water addition control method in the preparation process of laboratory-grade non-fired bricks made from slag. This method is applied to laboratory brick-making equipment including a raw material moisture content detection unit, a material metering unit, a water addition execution unit, a stirring unit, an online humidity detection unit, and a central controller. See also... Figure 2 and Figure 3 The technical solution of this method will be described in detail below.

[0032] Step S1: Weighing raw materials and detecting initial moisture content Raw materials are fed into the feed hopper, and the rapid detection unit measures the total mass of the raw materials in real time. and initial average moisture content The data is then uploaded to the central controller. The central controller calculates the dry weight of the raw materials based on their quality and initial moisture content. : Step S2: Calculation of theoretical water addition, empirical compensation, and total target water addition The central controller determines the optimal moisture content based on the target formula. Raw material dry weight The theoretical water addition is dynamically calculated using the following model, along with a raw material characteristic compensation coefficient (preset according to the raw material type, such as clay or sand). and total target water addition : It can also be equivalently represented as: The two formulas above are equivalent expressions of the same mass conservation relationship. The first formula applies when the central controller has already calculated and retrieved the dry weight of the raw materials. In this case, the latter formula applies when the central controller directly calculates the total mass of raw materials. Initial average moisture content and target moisture content This is for scenarios involving rapid calculations. The results from both methods are consistent, improving the clarity of the algorithm's expression and adaptability to different data retrieval methods. The controller has a built-in raw material quality parameter verification program; this is implemented when the system simultaneously inputs the total wet mass of the raw materials. Raw material dry weight When there are two sets of parameters, the system automatically checks whether the theoretical dry weight calculation value matches the entered value. The verification formula is as follows: If the difference between the two calculations is greater than 0.1%, it is determined that there is an error in the raw material weighing / moisture content entry. The system will lock the entire subsequent water addition calculation process and pop up a window to prompt the operator to verify the raw material data.

[0033] Furthermore, the central controller calculates the initial empirical compensation amount without boundary treatment based on raw material characteristics, ambient temperature and humidity conditions, and equipment process losses. And the initial experience compensation amount Boundary limiting processing is performed to obtain the empirical compensation amount that will ultimately be used in the calculation of the total target water addition. .

[0034] Among them, the initial experience compensation amount Compensation item based on raw material characteristics Environmental evaporation compensation items and process loss compensation items Composition, calculated according to the following formula: in, It is used to compensate for the deviation in actual water demand caused by differences in particle composition, clay mineral content, specific surface area, water absorption capacity and water retention capacity of different slag raw materials; Used to compensate for moisture loss due to ambient temperature, relative humidity, and stirring exposure time; It is used to compensate for the effective water loss caused by the water addition unit, spray system, mixing tank wall, mixing blades, and discharge process.

[0035] To avoid excessive or insufficient compensation due to raw material classification errors, abnormal environmental evaporation compensation coefficients, equipment calibration deviations, or detection errors, the central controller does not directly... Used for the total target water addition Instead of calculating, first calculate... Boundary limiting processing is performed to obtain the final empirical compensation amount. .

[0036] Raw material characteristic compensation item This is used to compensate for deviations in actual water demand caused by differences in particle composition, clay mineral content, specific surface area, water absorption capacity, and water retention capacity of different slag raw materials. Preferably, the raw material characteristic compensation item... Determine using the following formula: in, This is the compensation amount for the characteristics of this batch of raw materials, in grams; This is the raw material characteristic compensation coefficient corresponding to a unit dry material mass, with the unit being g / kg dry material; This is the dry weight of the raw materials for this batch, in grams.

[0037] The type of construction waste raw material is determined based on its type. The type of construction waste raw material can be classified according to one or more of the following: Cclay content, Methylene Blue Value (MBV), and One-Minute Water Absorption Rate (A1). Cclay is used to characterize the mass percentage of clay minerals in the construction waste; MBV is used to characterize the specific surface area and adsorption capacity of fine particles; and A1 is used to characterize the short-term water absorption capacity of the construction waste. A1 testing uses a φ50mm permeable cylinder with a double layer of slow-draining quantitative filter paper at the bottom. The drainage time is controlled at 30s ± 2s. If the relative deviation of three tests is >10%, the extreme value is discarded, and the average of the remaining two sets is taken. If the deviation still exceeds the standard, the sample is re-screened and retested.

[0038] Preferably, the type of slag raw material and The values ​​are determined according to Table 1: Table 1 When at least two of the three indicators—Cclay, MBV, and A1—fall into the same category, the waste soil is classified into the corresponding category. If the results of the three indicators are inconsistent, the one-minute water absorption rate (A1) is used as the primary criterion, and is further verified in conjunction with the methylene blue value (MBV). If the categories corresponding to A1 and MBV differ by more than one level, resampling and testing are conducted, and the median value of the two or three tests is used as the classification basis. If significant differences still exist after verification, the higher water demand level is used for classification. To avoid the mixture becoming too dry, the difference in the unit dry matter compensation coefficient calculated from different indicators is ≥4g / kg, which is considered to be a step over one grade; if the indicator is judged to be two or more grades over, the raw material minerals and water absorption indicators must be resampled and tested.

[0039] Furthermore, when A1 exceeds 120 g / (kg·min) or MBV is greater than 6.0 g / 100 g dry soil, it indicates that the raw material has strong water absorption or swelling properties, and the central controller will... The limit is 12g / kg dry material, and operators are advised to individually calibrate the raw material or reduce the initial pre-water ratio to avoid excessive subsequent water replenishment due to the delayed water absorption of the raw material.

[0040] The above classification thresholds are recommended thresholds applicable to the small-batch preparation of non-fired bricks from slag in the laboratory of this invention. In practical applications, the classification thresholds can be manually verified or optimized by combining historical batch data, drying verification results, and brick forming performance test results.

[0041] Environmental evaporation compensation items Used to compensate for moisture evaporation loss caused by ambient temperature, relative humidity, and stirring exposure time. Ambient evaporation compensation coefficient. Calculate using the following formula: in, This is the environmental evaporation compensation coefficient, expressed in grams. The environmental evaporation compensation coefficient is given per unit dry material mass, expressed in g / (kg dry material·kPa·min). The dry weight of the raw materials for the actual brick-making batch is in grams; VPD is the vapor pressure difference, in kPa. This refers to the effective exposure time of the mixture during the actual brick-making process, expressed in minutes.

[0042] The vapor pressure difference VPD is calculated using the following formula: Where T is the ambient temperature in °C; RH is the ambient relative humidity in °C; and e is the natural constant.

[0043] The above VPD calculation formula is a simplified Magnus formula applicable to the commonly used temperature range in laboratories. Preferably, when the ambient temperature is within the range of 0 to 40°C, the controller calculates the vapor pressure difference (VPD) according to the above formula; when the ambient temperature is below 0°C or above 40°C, the controller calculates the VPD according to the preset boundary temperature value, or prompts the operator to separately calibrate the environmental evaporation compensation coefficient.

[0044] In extreme cases, the system can be recalibrated according to preset boundary values ​​or by recalibrating the environmental evaporation compensation coefficient βm. When the central controller uses the environmental evaporation compensation coefficient β under the current batch material quality for calculation, it can also be calculated using the following formula: Where β is the environmental evaporation compensation coefficient under the current batch material mass, in g / (kPa·min), and use The advantage of using β is that it facilitates the conversion between the quality of materials from different batches, while the advantage of using β is that it facilitates direct calling under the same equipment and batch conditions.

[0045] Effective exposure time This refers to the effective time for moisture exchange between the raw materials and the outside air during the mixing process. For open mixing conditions, The actual mixing time can be used; for semi-open mixing conditions, The mixing time can be taken from the initial pre-addition of water until the moisture content of the mixture reaches a stable level; for closed mixing conditions... The calculation can be based on 0.2 to 0.6 times the actual mixing time, depending on the degree of equipment sealing.

[0046] Furthermore, The value can be determined through interpolation using a recommended value matrix lookup table, or through environmental evaporation calibration tests. When both recommended matrix values ​​and single-point calibration values ​​exist, the single-point calibration values ​​should be used first. When single-point calibration is not performed, the value obtained through recommended matrix interpolation should be used. This serves as the initial value. Subsequent batches of data are used to generate verification records or correction suggestions for the environmental evaporation compensation coefficient. These correction suggestions are then confirmed by the operators and used to update the environmental evaporation compensation coefficient for the corresponding operating conditions.

[0047] Furthermore, This can be obtained through an environmental evaporation calibration test. The calibration method is as follows: Under the conditions of the mixing equipment, mixing speed, and loading, take standard quartz sand or pre-homogenized inert fine aggregate that has been dried and cooled to room temperature as the calibration material, add a known mass of water to reach the preset moisture content, and weigh the total mass of the equipment and materials before mixing; then mix for a preset time at a set ambient temperature T and relative humidity RH. No water is added during the mixing process; immediately after mixing, weigh the total mass of the equipment and materials. The difference in total mass before and after mixing is the evaporation loss under those environmental conditions. Calculate using the following formula. : in, for Dry weight of materials used for environmental evaporation coefficient calibration, in grams; The evaporation loss measured during the calibration process is expressed in grams. for The calibrated stirring time is expressed in minutes. At least three parallel calibrations should be performed under the same temperature and humidity conditions, and the average value should be taken as the calibration result under those conditions. If the relative deviation of the three results exceeds 15%, then recalibrate.

[0048] Therefore, The calibration formula and The calculation formulas are derived from the same evaporation loss model. The difference lies in the fact that the calibration stage uses the measured evaporation loss. Inverse calculation model parameters The actual control stage is based on the established... Calculate the environmental evaporation compensation item for the current batch. .

[0049] Furthermore, when single-point calibration is not completed under the corresponding temperature and humidity conditions, the central controller can use an environmental evaporation compensation coefficient. The initial recommended matrix is ​​used as the initial value, and the values ​​are determined by linear or bilinear interpolation based on the actual ambient temperature T and relative humidity RH. The initial reference values ​​are as follows. The initial recommended matrix is ​​applicable to the preparation of non-fired bricks from slag under semi-open mixing conditions in the laboratory, with a mixing speed of about 60 rpm and a single batch dry material weight of 2-5 kg. The values ​​are shown in Table 2: Table 2 Table The unit is g / (kg dry material·kPa·min).

[0050] When the actual ambient temperature T or relative humidity RH falls between two adjacent values ​​in the table, the central controller uses linear interpolation or bilinear interpolation to determine the value. Specifically, interpolation can be performed first between two adjacent relative humidity values, and then between two adjacent temperature values ​​to obtain the values ​​under the current environmental conditions. The initial reference value.

[0051] When both the recommended matrix value and the single-point calibration value exist, the central controller preferentially uses the single-point calibration value as the value under the current operating condition. When single-point calibration is not performed, the central controller uses the recommended matrix interpolation. As initial values, the actual evaporation losses, endpoint moisture content deviations, and drying verification results recorded in subsequent batches can be used to form verification records or adjustment suggestions for the environmental evaporation compensation coefficient. These can be used to update the environmental evaporation compensation coefficient under the corresponding operating conditions after confirmation by the operators.

[0052] When RH is greater than 90% or VPD is less than 0.10 kPa, the environmental evaporation loss is small, and the central controller can... Take 0 or select the lowest level Calculation: When T is above 40℃ or RH is below 30%, the central controller performs initial calculations based on the closest boundary value in the recommended matrix and prompts the operator to verify the environmental evaporation compensation coefficient or perform single-point calibration to avoid insufficient evaporation compensation under high temperature and low humidity conditions.

[0053] The above recommendation matrix is ​​only used as an environmental evaporation compensation coefficient in the small-batch laboratory preparation process of non-fired bricks made from slag. The initial recommended value is not limited to determining the environmental evaporation compensation coefficient under the current operating conditions through single-point calibration or multi-point calibration. In practical applications, The environmental evaporation compensation coefficient can be reviewed or recalibrated by taking into account factors such as the opening degree of the mixing equipment, the mixing speed, the loading amount, the exposure state of the material surface, the ambient airflow conditions, and historical batch data.

[0054] Process loss compensation item This is used to compensate for the effective water loss caused by the water addition unit, spray system, mixing tank wall, mixing blades, and discharge process. Effective water loss includes water residue in the liquid metering pump and pipeline, water that did not enter the mixture from the spray atomization, water adhering to the mixing tank wall or mixing blades, and water that did not enter the effective mixture according to the actual discharge method.

[0055] The calibration was determined through equipment process calibration tests. The preferred calibration material is standard quartz sand or inert fine aggregate with low water absorption. The calibration material is dried to constant weight at 105±5℃ and cooled to room temperature, with a methylene blue value (MBV) less than 0.5 g / 100g dry material and a water absorption rate (A1) less than 5 g / (kg·min), to reduce the impact of the calibration material's own water absorption characteristics on... The impact.

[0056] The equipment process calibration test is conducted under equipment and process conditions corresponding to the actual brick-making mixture mixing process. Specifically, this includes using the same mixing equipment, the same liquid metering pump, the same spray pipeline and nozzles, and ensuring that the mixing speed, spraying method, mixing tank opening state, loading amount, mixing time, and discharge method are consistent with or correspond to the actual brick-making process. If the residue on the tank wall is not scraped during the actual brick-making process, it will not be scraped during calibration; if a fixed scraping procedure is set during the actual brick-making process, the same scraping procedure will be used during calibration.

[0057] Water addition amount in calibration instructions during process calibration tests According to the compensation items not included in the process loss The expected water volume before Confirmed, among which: in, Not included The estimated amount of water to be added is in grams. The calibration water addition amount is the output of the central controller during process calibration, in g; λ is the calibration water addition amount correction coefficient, which is 0.8 to 1.2, preferably 0.9 to 1.1.

[0058] By making Approximately the expected water addition during the actual brick-making process This allows the process calibration results to more accurately reflect the effective water loss of the liquid metering pump, spray pipeline, nozzles, tank wall, and agitator near the actual water addition volume. If the equipment is used for a long time under various water addition conditions, it can be calibrated separately at low, medium, and high water addition levels, and adjusted according to actual conditions. Choose the closest calibration result, or use interpolation to determine the result. .

[0059] The calibration steps are as follows: The first step is to weigh out the dry mass as follows: The calibration material is then added to the mixing unit; The second step involves the central controller controlling the liquid metering pump to add water according to the calibrated instructions. Add water to the mixing unit; The third step is to adjust the mixing speed and time according to the actual brick-making process. Stir, and do not add any additional water during the stirring process; Fourth, after mixing, collect the calibrated material according to the actual discharge method, and verify the effective water content in the collected material by weighing and drying. ; Step 5: Based on the temperature T, relative humidity RH, and calibration stirring time under the calibration environment. 1. Calibrate the dry weight of the material and environmental evaporation compensation coefficient Calculate the environmental evaporation loss during the process calibration period. ; Step 6: Calculate the process compensation amount obtained from the i-th calibration using the following formula: in, The compensation amount obtained from the calibration of the i-th process is expressed in grams. The calibration water addition amount is the output of the central controller command during the i-th calibration, in grams. The effective water content in the material collected after the i-th calibration is expressed in grams. The value represents the water loss due to environmental evaporation during the i-th calibration process, expressed in grams.

[0060] in, It can be determined by the following formula: in, The mass of wet calibration material collected after the i-th calibration according to the actual discharge method is expressed in g. The dry weight of the collected material after drying to constant weight is expressed in grams.

[0061] in, Calculate using the following formula: in, for The dry mass of the calibrated material is expressed in grams. for Water vapor pressure difference under calibration conditions, in kPa; for The calibrated stirring time is expressed in minutes. When the calibration environment is consistent with the actual brick-making environment, VPD can be taken from the actual brick-making environment.

[0062] Perform at least three parallel calibrations under the same equipment operating conditions, and take the results. The average value is used as the process loss compensation item under the operating conditions of the equipment. ; If the relative deviation of three calibration results exceeds 15%, calibration should be performed again. If the liquid exceeds the range of -5g to +5g, check for any abnormalities in the liquid metering pump, pipeline, nozzle, mixing tank wall, and discharge method, and recalibrate after maintenance.

[0063] when When the value is positive, it indicates that the actual amount of water entering the effective mixture is less than the amount of water added as instructed by the central controller, and a corresponding compensation amount needs to be added to the total target amount of water added; when... When the value is negative, it indicates that there is excessive water output from the liquid metering pump or the sprinkler system. The central controller will deduct the corresponding compensation amount when calculating the total target water addition.

[0064] If the liquid metering pump, spray pipeline, nozzles, mixing tank, or mixing paddle is replaced, or if the actual loading volume, mixing speed, or spraying method differs significantly from the calibration conditions, the calibration should be repeated. Calibration.

[0065] In determining , and Then, the central controller first calculates the initial empirical compensation amount without boundary processing. : in, This represents the initial empirical compensation amount without boundary treatment, expressed in grams.

[0066] To avoid excessively large or small empirical compensation amounts due to raw material classification errors, abnormal environmental evaporation compensation coefficients, equipment calibration deviations, or detection errors, the central controller uses the empirical compensation amount to calculate the total target water addition. Before, to Perform boundary limiting processing.

[0067] The central controller first Converted to unit dry material experience compensation amount : in, This is the empirical compensation amount per unit of dry material without boundary treatment, expressed in g / kg dry material.

[0068] Preferably, the lower limit of the unit dry material experience compensation amount The maximum empirical compensation per unit dry material is -6g / kg. It is 25g / kg dry material.

[0069] when At that time, take: when At that time, take: when At that time, take: in, This is the unit dry material experience compensation amount after boundary limiting processing.

[0070] Final empirical compensation amount after boundary limiting processing Determine using the following formula: The above-mentioned limiting processing can also be equivalently expressed as: in: when When the amplitude exceeds the above limits, the central controller records the abnormal state and prompts the operator to take appropriate action. , The verification process is then performed. Further, the central controller sets a recalibration trigger threshold Eth, which is determined by the following formula: in, To recalibrate the trigger threshold, in grams; The lower limit of absolute error is 3 to 8g, preferably 5g; The relative error coefficient has a value of 0.05 to 0.15, preferably 0.10; This represents the theoretical amount of water to be added, expressed in grams.

[0071] If two or more consecutive batches appear Exceeding the limit, or Compared to the limited amplitude The difference between them is greater than If the central controller prompts for re-testing of raw materials, calibration of environmental evaporation compensation coefficient, or calibration of equipment process, the system will then be activated.

[0072] Simultaneously, the minimum stable output of the liquid metering pump, weighing error, humidity detection fluctuation, and equipment calibration repeatability error in the small-batch brick making process in the laboratory are considered, as well as the impact of differences in theoretical water addition between different batches on the allowable range of compensation error. This is achieved by setting... This can avoid frequent recalibration caused by small deviations, and at the same time, it can promptly prompt for verification when the compensation deviation is too large relative to the theoretical water addition.

[0073] After the above boundary treatment, the central controller calculates the total target water addition volume using the following formula. : in, This is the theoretical amount of water to be added. This is the final empirical compensation amount after boundary processing. The total amount of water added is the target amount.

[0074] like If ≤0, the central controller will Set to 0 and issue a prompt indicating that the initial moisture content of this batch of raw materials may have reached or exceeded the target moisture content, and do not perform initial pre-water addition; if If the value is >0, proceed to the subsequent initial pre-watering step.

[0075] Step S3: Initial pre-filling of water and adjustment of the pre-filling water ratio The central controller calculates the total target water addition based on step S2. Determine whether it is necessary to adjust the initial pre-added water ratio accordingly.

[0076] To avoid the total target water addition When the water level is low, adding most of the water at once with a high pre-addition ratio can cause localized over-wetting, insufficient subsequent feedback adjustment space, or inability to correct the situation after pre-addition. The central controller then... The size determines the actual pre-added water ratio .

[0077] Let the threshold for determining small water addition be... Preferably: in, The maximum amount of water to be added at one time is 5-20g, with 15g being the preferred value.

[0078] Let the threshold for determining a moderate water addition be... Preferably: The central controller determines the actual pre-filled water ratio according to the following rules. : when ≥ hour, The value should be between 0.85 and 0.92, preferably 0.90; when ≤ < hour, The value should be between 0.70 and 0.85, preferably 0.80. When 0 < < hour, The value should be between 0.30 and 0.70, preferably 0.60; when When ≤0, =0, initial pre-filled water volume =0.

[0079] Meanwhile, to ensure that there is still room for adjustment in subsequent online humidity feedback and water replenishment, the central controller is set with a reserve amount for feedback water replenishment. : in, The amount of water reserved for feedback is expressed in grams; To address the water replenishment execution dead zone, preferably, a water replenishment execution dead zone is defined. The value ranges from 0.05 to 0.50 g, with a further preferred value of 0.10 g.

[0080] Final initial pre-filled water volume Determine using the following formula: when ≤ hour, Set the value to 0, and adjust the water supply using small pulses during the online humidity detection and PID feedback water supply stage.

[0081] Subsequently, the central controller controls the liquid metering pump to add the initial pre-added water to the mixing unit. This allows the moisture content of the mixture to quickly approach the target moisture content, while reserving adjustment space for subsequent online humidity feedback and PID micro-water replenishment.

[0082] Step S4: Online humidity detection and PID feedback water replenishment adjustment During the stirring process, the online humidity detection unit controls the sampling period according to a preset control. Real-time detection of actual moisture content of the mixture The test results are then transmitted to the central controller.

[0083] Preferably, the online humidity detection unit performs signal preprocessing on the raw humidity sampling signal to obtain the actual moisture content. Signal preprocessing includes moving average filtering and first-order hysteresis compensation; the time window for moving average filtering is 1 second, and the sampling period is... Number of sampling points within the window The filtered moisture content is the average of the most recent N original humidity samples. Based on this, first-order hysteresis compensation is performed according to the changing trend of two adjacent filtered moisture content values ​​to obtain the compensated actual moisture content. and the actual moisture content The input controller is used to calculate the moisture content deviation. Through the above signal preprocessing, the interference of local agglomeration, instantaneous material blockage of the sensor, or instantaneous changes in moisture content caused by local water film passing through the sensor during the stirring process on the PID water replenishment calculation can be reduced.

[0084] Control sampling period The sampling period is typically 0.5–5 seconds, preferably 1 second. The determination is based on the response time of the online humidity detection unit, the mixing and homogenization rate of the stirring unit, the minimum stable water output response time of the liquid metering pump, and the mass of a single batch of material. When When the moisture content is too low, the central controller may misinterpret instantaneous noise from the sensor or localized fluctuations in moisture content as actual changes in moisture content, leading to frequent start-stop cycles of the liquid metering pump and control shudder; when When the moisture content is too high, the central controller will be slow to respond to changes in the moisture content of the mixture, which may lead to untimely water replenishment or moisture content overshoot.

[0085] To eliminate detection errors caused by sensor drift over long-term use, the system has a built-in automatic calibration reminder mechanism: after every 20 batches of mixture preparation is completed, the controller pops up a window prompting the operator to perform a three-point calibration using the drying method; during calibration, homogeneous slag with three standard moisture contents of 10%, 15%, and 20% is prepared and sequentially fed into the mixing tank to collect the original sensor readings. The actual measured moisture content after drying is fitted with the sensor readings to obtain the calibration compensation coefficient, which is automatically stored in the central controller's storage unit. All subsequent humidity sampling data are automatically substituted into this coefficient to complete the correction.

[0086] Central controller will and Compare and calculate the moisture content deviation: That is, the moisture content deviation at the kth sampling time.

[0087] The central controller employs an incremental digital PID control algorithm to monitor the real-time moisture content of the mixture during the mixing process. Perform closed-loop regulation. The algorithm expression is as follows: in, This represents the increment of water replenishment during the kth sampling period (i.e., the change in the amount of water that needs to be added or reduced, in milliliters or grams). These represent the deviations from the previous and previous two samplings, respectively; These represent the proportional, integral, and differential coefficients (constants that have been experimentally tuned).

[0088] Preferably, , , The control parameters were obtained through pre-experiment tuning and adjusted based on the single batch material quality, target moisture content, online humidity detection unit response time, minimum water output of liquid metering pump, and water absorption response characteristics of the mixture.

[0089] Regarding PID parameter tuning, in this invention, the moisture content deviation... In percentage terms, that is, when the target moisture content is 15.0% and the actual moisture content is 14.5%, ,at this time , , All units can be expressed as g / %.

[0090] Preferably, the PID pre-tuning test adopts the step water replenishment response method. Specifically, after the initial pre-water addition and homogenization, the mixture is brought to a slightly dry state with a moisture content lower than the target; the central controller controls the liquid metering pump to add a step water replenishment amount. Continue stirring and record the moisture content change curve measured by the online humidity detection unit.

[0091] Step water replenishment The preferred method is determined by the following formula: After the moisture content of the mixture reaches a stable level, calculate the difference in stable moisture content before and after the step water injection. The unit moisture content response water of the mixture is determined by the following formula. : in, The difference in stable moisture content before and after step water replenishment is expressed in percentage points. The amount of water required to make up the moisture content of the mixture by 1 percentage point, expressed in g / %.

[0092] Central controller according to Sure , , The initial value. Preferably: in, This is the proportional tuning factor, ranging from 0.12 to 0.25; The integral tuning factor is 0.08 to 0.18. The differential integration coefficient is taken as 0.005 to 0.03.

[0093] Even without conducting a step-response water replenishment test, the central controller can also use a baseline operating condition conversion algorithm to determine the initial reference values ​​of the PID parameters. Preferably, the initial reference values ​​are based on the dry weight of the raw material. =2760g, target moisture content =15.0%, stirring speed Based on the reference parameters at 60 rpm, and according to the dry weight of a single batch of raw materials... Target moisture content The stirring speed n is proportionally converted to the reference PID parameter: in, This is a correction factor for the stirring speed. Preferably, when the stirring speed n is 30–60 rpm, Take a value of 0.75 to 1.00; when n is 60 to 90 rpm, Take a value of 1.00 to 1.15; when n is 90 to 120 rpm, Take a value of 1.10 to 1.30.

[0094] In the above conversion process, the dry weight of the raw materials Used to reflect the impact of different material qualities on the water replenishment response, target moisture content A stirring speed correction factor used to reflect the difference in water required per unit change in moisture content under wet conditions. It is used to reflect the differences in water diffusion rate, online humidity response rate, and homogenization rate after water replenishment under different stirring speeds.

[0095] Under the conditions of a total wet mass of 500–5000 g of material per batch in the laboratory, a target moisture content of 10%–20%, and a stirring speed of 30–120 rpm, the central controller can first calculate according to the above formula. , , The initial reference values ​​are then used to verify or limit the conversion results according to Table 3: Table 3 Table , , The units are all g / %; where "%" represents the percentage point value of moisture content deviation. The above recommended range is the PID parameter calibration range after correction for material quality, target moisture content, and stirring speed. If obtained according to the baseline operating condition conversion method... , , If the value exceeds the recommended range for the corresponding material quality, the central controller can limit it to within the recommended range and make secondary corrections through step water replenishment response tests or subsequent batch data.

[0096] Furthermore, if When the flow rate exceeds the preset dead zone, the central controller controls the liquid metering pump to add the corresponding amount of water to the mixing unit; if... When the liquid metering pump is less than or equal to the preset dead zone, it will not operate; if the actual moisture content is less than or equal to the preset dead zone, it will not operate. If the moisture content continuously exceeds the upper limit of the target allowable moisture content, the central controller will issue an alarm signal and prompt the operator to add a trace amount of dry material or prepare the batch of mixture again.

[0097] Regarding PID output boundary handling and water replenishment execution, further measures are taken to avoid control jitter caused by frequent start-stop of the liquid metering pump, excessively small water replenishment commands, and negative water replenishment commands resulting from PID calculations. The central controller performs the following checks before executing water replenishment: Perform negative value truncation, execute dead zone judgment, and limit the upper limit of single water replenishment.

[0098] First, the central controller uses the theoretical water replenishment increment calculated by the PID controller. The nonnegation process is performed to obtain the nonnegative water replenishment volume. : =max[ ,0] In other words, when When it is a positive value, equal ;when When it is zero or negative, Set to 0. This limits the control boundary of this method to "water replenishment only, no drainage", meaning that the central controller only controls the liquid metering pump to perform positive water replenishment, and does not perform drainage or pumping operations.

[0099] Then, the central controller executes the dead zone based on the water replenishment. and the maximum amount of water replenished at one time Determine the actual amount of water to be replenished. Its control rules are as follows: when ≤ hour, =0; when > hour, =min[ , ].

[0100] in, Dead zones were created to allow for water replenishment. This is the maximum water replenishment limit per cycle. Preferably, there is a dead zone for water replenishment. The value ranges from 0.05 to 0.50 g, with a further preferred value of 0.10 g; the upper limit for a single water replenishment. The value ranges from 5 to 20g, with 15g being a more preferred value.

[0101] Furthermore, the water replenishment execution dead zone The design is based on the following: Firstly, liquid metering pumps have a minimum stable output flow rate. When the replenishment flow rate is lower than this minimum stable output flow rate, the actual metering accuracy is difficult to guarantee. Secondly, online humidity detection units experience instantaneous fluctuations. If replenishment is performed for every small PID output, it can easily cause frequent start-stops of the metering pump and fluctuations in moisture content adjustment. Therefore, by setting a replenishment execution dead zone, invalid small-pulse replenishment commands can be filtered out, improving the stability of replenishment execution. Under laboratory conditions where the mass of a single batch of material is 2–5 kg, the change in wet basis moisture content corresponding to a replenishment flow rate of 0.05–0.50 g is much smaller than the allowable error of the target moisture content, thus not reducing the accuracy of the final moisture content control.

[0102] Furthermore, the upper limit for a single water replenishment. This is used to limit the maximum water replenishment volume of the liquid metering pump within a single sampling cycle, preventing excessive water replenishment due to large instantaneous moisture content deviations, sensor fluctuations, or overly strong PID parameter responses, which could lead to localized overwetting or moisture content overshooting of the mixture. If the non-negative water replenishment volume is calculated by the PID... Less than or equal to The actual amount of water replenished is equal to ;like Greater than The actual water replenishment volume is then limited to... .

[0103] Furthermore, if If the value is greater than 0, the central controller controls the liquid metering pump to add the corresponding amount of water to the mixing unit; if... If the value is 0, the liquid metering pump will not operate.

[0104] If the actual moisture content If the moisture content remains consistently above the target upper limit, the central controller will issue an alarm signal and prompt the operator to add a trace amount of dry material or prepare the batch of mixture anew. "Constantly above the target upper limit" means that the online humidity detection unit, at a sampling cycle... Perform testing, when continuous All control sampling periods satisfy: At that time, the mixture was determined to be in a state of continuous excessive moisture. The allowable error for the target moisture content is preferably 0.3%; The continuous over-limit judgment time is set to 5-10 seconds, preferably 5 seconds; The number of consecutive exceedances is determined by the following formula: in, Indicates the time for continuous over-limit judgment. According to the sampling period Converted to the number of samples and rounded up, this ensures that the actual continuous over-limit judgment time is not less than the preset judgment time. ; This indicates that at least two consecutive exceedance checks are required to prevent a single abnormal sample value, sensor transient noise, or localized material fluctuations from directly triggering the over-humidity alarm. When the sampling period is short, the system requires more consecutive exceedance sampling points to trigger an alarm; when the sampling period is long, fewer consecutive exceedance sampling points correspond to a longer actual duration. You can choose 2.

[0105] If only a single or short-term exceedance occurs, the central controller will not immediately alarm, but will stop water replenishment and continue stirring and homogenization; an alarm will only be triggered when the actual moisture content continuously exceeds the upper limit of the target moisture content.

[0106] Repeat the above online detection, deviation calculation, and water replenishment adjustment process until... Stable at Within the allowable error range. Preferably, the allowable error range is: Furthermore, after this state continues for a preset time, it is determined that the batch of mixture has reached the target moisture content requirement.

[0107] Step S5: Associate data records with batches When the actual moisture content of the mixture Stabilize at the target moisture content Once the allowable error range is reached, the central controller automatically generates a unique batch number for that batch of mixture and records the total wet mass of the raw materials for that batch. Initial moisture content Target moisture content Raw material dry weight Theoretical water addition Raw material characteristic compensation item Environmental evaporation compensation coefficient Process loss compensation item Initial experience compensation amount Final experience compensation amount Total target water addition Actual pre-added water ratio Initial pre-filled water volume Real-time moisture content at each sampling time Moisture content deviation PID water replenishment increment Actual water replenishment volume The cumulative water replenishment, ambient temperature, ambient humidity, and final stable moisture content are recorded and stored.

[0108] The central controller correlates the aforementioned water addition control data with the molding parameters, curing parameters, and subsequent performance test results of the corresponding batch of brick blanks to form a complete process data record for that batch of slag-fired non-fired bricks; and based on the process data from multiple batches, it adjusts... , , , Alternatively, provide a basis for review or suggestions for correction of the PID control parameters.

[0109] Based on the embodiments provided in this application, the initial moisture content detection of raw materials is combined with an empirical compensation model to achieve feedforward prediction of water addition, thereby improving the accuracy of initial water addition; the combination of online humidity detection and PID closed-loop control enables real-time correction of the moisture content of the mixture, ensuring that the final moisture content is stably controlled near the target value; a dual control mechanism of feedforward calculation and feedback adjustment is constructed to reduce moisture content deviation caused by raw material fluctuations and environmental changes, thereby improving experimental repeatability; and the water addition process data is automatically recorded, providing a foundation for establishing a correlation database between slag properties, process parameters, and brick performance.

[0110] Example 1: Adaptive water control method for ordinary engineering waste soil: The overall process of the adaptive water addition control method of the present invention, including S1 to S5, as well as the determination of raw material dry weight calculation, theoretical water addition calculation, raw material characteristic compensation item, environmental evaporation compensation coefficient and process loss compensation item, boundary limit processing of initial empirical compensation amount, determination of final empirical compensation amount and total target water addition amount, linkage adjustment of initial pre-water addition ratio and feedback water replenishment reserve mechanism, PID parameter tuning or conversion, PID water replenishment increment calculation and output boundary processing, over-humidity alarm and continued stirring and homogenization strategy, and water addition control data recording and batch association method, can be described through this embodiment.

[0111] Regarding the overall process of steps S1 to S5: In this embodiment, the "total mass of raw materials" in step S1 is 3000g and the "initial moisture content" is 8.0%, based on which the "dry weight of raw materials" is calculated. The target moisture content is 2760g; in step S2, the target moisture content is... The theoretical water addition is 15.0%. The calculated weight using the formula is 247.06g, plus the raw material characteristic compensation item. Environmental evaporation compensation items and process loss compensation items The initial empirical compensation amount is determined and summed using the methods described above. The weight is 16.10g, after the above-mentioned boundary limiting treatment (converted to the empirical compensation amount per unit dry material). After setting the dry material concentration to 5.83 g / kg (within the range of -6 to 25 g / kg dry material), the empirical compensation amount ΔQ is 16.10 g, and the total target water addition amount Q is 263.16 g. In step S3, the initial pre-added water amount is determined according to the pre-added water ratio linkage adjustment rule. It is 236.84g and is output by a liquid metering pump, with a feedback replenishment reserve. The sample size is 21.05g. In step S4, the sampling period is controlled to be 1s. The online humidity detection unit measures that the actual moisture content after stirring for 15s is 13.80%. The incremental water replenishment increment is calculated according to the incremental digital PID control algorithm and water is replenished successively until the deviation between the actual moisture content and the target moisture content is within the allowable error range of ±0.3%. In step S5, the entire process data of this batch is recorded and stored, a unique batch number is generated and associated with the subsequent brick performance test results.

[0112] Regarding the boundary limiting processing of empirical compensation, this embodiment... The concentration was 5.83 g / kg dry matter, which did not trigger the limit treatment; if it exceeds the range of -6 to 25 g / kg dry matter, or if multiple batches exceed the limit consecutively, or If the difference between the current value and the limit value ΔQ is greater than the recalibration trigger threshold, it will prompt the user to re-perform raw material classification testing, environmental evaporation compensation coefficient calibration, or equipment process calibration.

[0113] Regarding the feedback and water replenishment reserve mechanism, in this embodiment... The value calculated using max{0.08Q,5ud} is 21.05g. Take 236.84g, which satisfies the requirement that the initial pre-added water amount does not exceed the difference between the total target added water amount and the feedback replenishment reserved amount.

[0114] Regarding PID output boundary handling, in this embodiment, the PID calculated the water replenishment increment as -0.04g during the 12th sampling, and after nonnegation processing, the actual water replenishment amount was 0g; the actual water replenishment amount in each sampling did not exceed the upper limit of a single water replenishment. =15g, which reflects the three-level boundary processing rule of "non-negativity processing - dead zone filtering - upper limit limiting" mentioned above.

[0115] Regarding the over-humidity alarm and the strategy of continuing stirring and homogenization, this embodiment sets the number of consecutive exceedance judgments to 5. When the actual moisture content is higher than the upper limit of the target moisture content for 5 consecutive sampling cycles, the alarm will be triggered. An alarm is triggered when the content reaches +0.3% = 15.3%, prompting the addition of trace amounts of dry material or a restart. Otherwise, water replenishment is stopped and stirring and homogenization continues.

[0116] Regarding the calibration method for the process loss compensation item, this embodiment uses standard quartz sand dried to constant weight at 105±5℃ as the calibration material. Calibration is performed under conditions corresponding to the actual brick-making process: mixing equipment, liquid metering pump, spray pipeline, 60 rpm rotation speed, semi-open state, and 3 min mixing time. The calibration instruction for water addition is 250.00 g. After mixing, the calibration material is collected, dried, and verified. The effective water volumes obtained from three parallel calibrations are 242.80 g, 243.20 g, and 243.00 g, respectively, corresponding to single-process loss compensation amounts of 4.20 g, 3.80 g, and 4.00 g, respectively. The relative deviation of the three results does not exceed 15%, and the average value of 4.00 g is taken as the process loss compensation item under the equipment operating conditions.

[0117] Regarding the data recording and batch association method, this embodiment generates a unique batch number, records and stores the following: total wet mass of raw materials 3000g, initial moisture content 8.0%, target moisture content 15.0%, raw material dry weight 2760g, theoretical water addition 247.06g, raw material characteristic compensation 9.10g, environmental evaporation compensation 3.00g, process loss compensation 4.00g, total target water addition 263.16g, initial pre-added water 236.84g, actual moisture content at each sampling time, moisture content deviation, PID water replenishment increment, actual water replenishment, cumulative water replenishment, ambient temperature 26℃, ambient humidity 52%, and final stable moisture content 14.95%. These data are then associated with the forming parameters, 7-day curing parameters, and compressive strength test result of 13.10MPa for this batch of brick blanks, forming a complete process data record.

[0118] This embodiment uses a laboratory-scale non-fired brick preparation equipment for slag soil, equipped with a raw material moisture content detection unit, a material metering unit, a liquid metering pump, a spraying system, a mixing unit, an online humidity detection unit, and a central controller. The raw material moisture content detection unit detects the initial moisture content of the raw materials during the feeding stage, the online humidity detection unit detects the real-time moisture content of the mixture during the mixing process, and the central controller performs theoretical water addition calculations, empirical compensation calculations, pre-water addition control, PID feedback water replenishment control, and batch data recording.

[0119] For ease of explanation, the definitions of each variable in this embodiment are shown in Table 4: Table 4 In this embodiment, the total wet mass of a single batch of slag raw material is... The weight is 3000g, and the raw material is pre-homogenized ordinary construction waste soil with an initial moisture content of [missing information]. The target moisture content is 8.0%. The value was 15.0%. The ambient temperature T was 26℃, the relative humidity RH was 52%, the stirring speed n was 60 rpm, and the sampling period was controlled. It takes 1 second.

[0120] The composition of the ordinary engineering waste soil used in this embodiment was determined by sieving, laser particle size analysis, and semi-quantitative X-ray diffraction analysis. By particle size, sand accounted for approximately 42%, silt for approximately 39%, and clay for approximately 19%. By major mineral composition, quartz accounted for approximately 46%, feldspar for approximately 14%, calcite for approximately 7%, and clay minerals for approximately 18.6%, with the remainder being small amounts of mica, iron oxides, organic matter, and amorphous components. The clay minerals mainly included illite, kaolinite, chlorite, and a small amount of montmorillonite. The methylene blue value (MBV) of this raw material was 2.4 g / 100 g dry soil, and the water absorption rate (A1) was 46 g / (kg·min). Therefore, this raw material belongs to the category of ordinary engineering waste soil.

[0121] Step S1: Weighing raw materials and detecting initial moisture content After the raw materials enter the equipment through the feed hopper, the total wet mass of the raw materials is obtained by the material metering unit: The initial moisture content was measured by the raw material moisture content detection unit: % The central controller calculates the dry weight of the raw materials based on the total wet mass and initial moisture content: That is, the dry weight of this batch of raw materials is 2760g.

[0122] Step S2: Calculate the theoretical water addition and the empirical compensation amount. First, calculate the theoretical water addition under strict mass conservation: In this embodiment, the empirical compensation amount Compensation amount based on raw material characteristics Environmental evaporation compensation items and process compensation amount composition: Regarding the compensation item for raw material characteristics In this embodiment, the determination of the raw material characteristic compensation item is as follows: First, the pre-homogenized engineering waste soil was subjected to raw material classification and testing. The testing indicators included clay mineral content (Cclay), methylene blue value (MBV), and water absorption rate (A1) per minute.

[0123] Among them, the clay mineral content Cclay was obtained by semi-quantitative X-ray diffraction analysis and was used to characterize the mass percentage of clay minerals such as kaolinite, illite, montmorillonite, and chlorite in the raw material; the methylene blue value MBV was used to characterize the specific surface area and adsorption capacity of the fine particles in the raw material; and the water absorption rate A1 was used to characterize the water absorption and water retention capacity of the raw material in a short time.

[0124] The method for detecting the water absorption rate A1 in one minute is as follows: Take a slag sample that has been dried to constant weight at 105±5℃ and cooled to room temperature, sieve out coarse particles larger than 5mm, and weigh the dry sample (m0). Place the dry sample in a permeable sample tube with filter paper at the bottom, so that the bottom of the sample is in contact with the water surface and capillary water absorption occurs for 60 seconds. After 60 seconds, remove the sample tube, let it stand to drain for 30 seconds, wipe off the water adhering to the outer wall, and weigh the water-absorbed sample (m1). Calculate the water absorption rate in one minute using the following formula: Wherein, the unit of A1 is g / (kg·min). The same raw material shall be tested in parallel at least 3 times, and the average value shall be taken as the water absorption rate per minute of the batch of raw material; if the relative deviation of the three results exceeds 10%, the sample shall be resampled and tested.

[0125] In this embodiment, the clay mineral content (Cclay) of the ordinary engineering waste soil was found to be 18.6%, the methylene blue value (MBV) was 2.4 g / 100g dry soil, and the water absorption rate (A) was 46 g / (kg·min). According to the above classification criteria, Cclay is within the range of 10% to 25%, MBV is within the range of 1.0 to 3.5 g / 100g dry soil, and A1 is within the range of 20 to 60 g / (kg·min). All three indicators fall within the range of ordinary engineering waste soil, therefore, this raw material is classified as ordinary engineering waste soil.

[0126] Compensation coefficient for unit dry material properties of ordinary construction waste Take 0-5 g / kg of dry material. In this embodiment, based on the water absorption rate A1 = 46 g / (kg·min), select... =3.30g / kg dry weight. This batch of raw materials has a dry weight of 3.30g / kg. The weight is 2760g, therefore the raw material characteristic compensation item... for: Therefore, the raw material characteristic compensation item in this embodiment Take 9.10g to compensate for the deviation in theoretical water addition caused by the adsorption and retention of water by fine particles and clay minerals in ordinary engineering waste soil and short-term water absorption.

[0127] Regarding the environmental evaporation compensation coefficient Furthermore, in this embodiment, the environmental evaporation compensation coefficient is determined. Based on ambient temperature T, relative humidity RH, vapor pressure difference VPD, effective exposure time, and environmental evaporation compensation coefficient Sure.

[0128] In this embodiment, the ambient temperature T is 26℃, the relative humidity RH is 52%, and the effective exposure time is 3 minutes. The vapor pressure difference VPD is calculated using the following formula: Substituting T=26 and RH=52, we get: In this embodiment, before performing single-point calibration, the central controller can first refer to the technical solution... The initial recommendation matrix determines the initial reference value for the environmental evaporation compensation coefficient. Since the ambient temperature T=26℃ in this embodiment is between 20℃ and 30℃, and the relative humidity RH=52% is between 50% and 70%, the central controller uses a bilinear interpolation method to determine... The initial reference value. After interpolation calculation, The initial reference value is approximately 0.216 g / (kg dry matter·kPa·min).

[0129] Furthermore, to ensure that the environmental evaporation compensation coefficient more accurately reflects the evaporation loss under the stirring equipment, semi-open stirring state, and actual loading conditions used in this embodiment, this embodiment employs a single-point calibration method to determine the final coefficient used for calculation. Pre-calibration procedures: Quartz sand is sieved through a 0.075~0.25mm sieve, dried at 105℃ for 24 hours, and then cooled to room temperature in a sealed, airtight environment. Before formal calibration, the nozzles and inner walls of the pipeline are thoroughly wetted by spraying the pipeline with circulating water for 3 minutes. The calibration test is conducted under equipment and process conditions corresponding to the actual mixing process of the brick-making mixture in this embodiment. Specifically, the mixing equipment used in this embodiment is employed, the mixing speed is 60 rpm, the mixing state is semi-open, and the dry weight is taken. 2760g of standard quartz sand was used as the calibration material. Water was added to achieve an initial moisture content of approximately 15%. The mixture was then stirred for 3 minutes at 26℃ and 52% relative humidity, without adding any more water during the stirring process. The total mass of the equipment and the material was weighed before and after stirring. After three parallel calibrations, the evaporation losses were measured to be 2.95g, 3.03g, and 3.02g, respectively, with an average evaporation loss of [missing value]. It weighs 3.00g.

[0130] According to the formula: Substitution =2760g, VPD=1.61kPa, =3min, we get: Therefore, the environmental evaporation compensation coefficient in this embodiment is determined. Take 0.225 g / (kg dry material·kPa·min).

[0131] The dry weight of this batch of raw materials The amount is 2760g, or 2.760kg, therefore the environmental evaporation compensation item... Calculate using the following formula: Substitution =0.225g / (kg dry material·kPa·min) =2760g, VPD=1.61kPa, =3min, we get: Therefore, the environmental evaporation compensation item in this embodiment Take 3.00g to compensate for the water evaporation loss during stirring at 26℃, 52% relative humidity, and 3min effective exposure time.

[0132] Since single-point calibration values ​​better reflect the current equipment and operating conditions than recommended matrix interpolation, this embodiment prioritizes using single-point calibration values. =0.225g / (kg dry material·kPa·min) .

[0133] Regarding compensation for process losses Furthermore, in this embodiment, the process loss compensation item is determined. This is used to compensate for effective water loss caused by residue in the liquid metering pump pipeline, spray atomization loss, and adhesion to the mixing tank wall and agitator blades. To determine the method used in this embodiment... Calibration was performed using equipment process calibration tests.

[0134] In this embodiment, low-absorption standard quartz sand is used as the calibration material. The standard quartz sand is dried to constant weight at 105±5℃ and cooled to room temperature. The methylene blue value (MBV) is less than 0.5g / 100g dry material, and the water absorption rate (A1) is less than 5g / (kg·min) per minute, so as to avoid the water absorption capacity of the calibration material itself from having a significant impact on the judgment of equipment process loss.

[0135] The calibration test was conducted under equipment and process conditions corresponding to the actual mixing process of the brick-making mixture in this embodiment. Specifically, the mixing equipment, liquid metering pump, spray pipeline and nozzles used in this embodiment were adopted, the mixing speed was set to 60 rpm, the mixing state was semi-open, and the mixing time was [not specified]. Take 3 minutes, and the discharge method is consistent with the actual brick-making process.

[0136] Determine the water addition volume required by the calibration command. First, calculate the items not included in the process loss compensation. The expected water volume before : In this embodiment, the theoretical water addition volume It is 247.06g, with a raw material characteristic compensation item. It is 9.10g, environmental evaporation compensation item It is 3.00g, therefore: To ensure that the calibration conditions of the process closely approximate the actual brick-making and water-addition process in this embodiment, a correction factor for the calibration water addition amount is adopted. =0.965, then the calibration command water addition amount is: Therefore, in this embodiment Take 250.00g. The amount of water added in this calibration instruction is not included in this embodiment. The estimated water addition of 259.16g is close to the actual water addition in this embodiment, and can be used to characterize process losses such as pipeline residue, spray loss, and adhesion to the barrel wall and agitator near the actual water addition.

[0137] In this embodiment, the dry mass is weighed. 2760g of standard quartz sand was added to the mixing unit, and the central controller controlled the liquid metering pump to add the calibrated amount of water. =250.00g. After adding water, stir at 60 rpm for 3 minutes. Do not add additional water during the stirring process. After stirring, collect the calibrated material according to the actual discharge method, and verify the effective water content in the collected material by weighing and drying. .

[0138] In this embodiment, The calibration ambient temperature T was 26℃, the relative humidity RH was 52%, and the calibration stirring time was [not specified]. It is 3 minutes. Based on the aforementioned calculations, Water vapor pressure difference under calibration environment ≈1.61 kPa, environmental evaporation compensation coefficient =0.225 g / (kg dry material·kPa·min). Therefore, Environmental evaporation loss during calibration process for: Substitution =2760g =1.61kPa =3min, we get: This embodiment performed three parallel calibrations, and the results are shown in Table 5: Table 5 The compensation amount for a single process is calculated using the following formula: For example, in the first calibration: The average of the three parallel calibration results is: Therefore, in this embodiment, the process loss compensation item Take 4.00g. This value indicates that under the conditions of the liquid metering pump, spray pipeline, nozzle, semi-open stirring state, stirring speed of 60rpm and actual discharge method used in this embodiment, about 4.00g of water does not form an effective water content in the mixture due to reasons such as pipeline residue, ineffective spraying into the mixture, and adhesion to the barrel wall or stirring blades, and needs to be compensated in the total target water addition.

[0139] about Boundary treatment and total target water addition The determination of, further, is obtained from the calculation. , and Then, the central controller first calculates the initial empirical compensation amount without boundary processing. : The dry weight of this batch of raw materials The weight is 2760g, or 2.760kg, therefore the empirical compensation amount per unit of dry material is... for: In this embodiment, the allowable range for the unit dry material empirical compensation is -6 to 25 g / kg dry material. Since δQcal = 5.83 g / kg dry material, which falls within the above allowable range, the central controller does not... Amplitude limiting is applied, that is: In this embodiment It did not exceed the limit, and Compared to the limited amplitude The difference between them is 0, so no recalibration prompt is triggered.

[0140] Therefore, the empirical compensation amount in this embodiment for: The final target water addition amount is obtained as follows: Step S3: Initial pre-filling of water and adjustment of the pre-filling water ratio The central controller calculates the total target water addition based on step S2. Determine whether it is necessary to adjust the initial pre-added water ratio accordingly.

[0141] In this embodiment, the water replenishment execution dead zone The maximum amount is 0.10g, which is the maximum amount that can be added to a single water replenishment. The threshold for determining the amount of water added is 15g. for: Threshold for determining medium water addition for: because =263.16g, greater than Therefore, this batch does not fall under the low-water-volume operation condition, and the central controller will use the actual pre-added water ratio: The feedback water replenishment reserve is: Therefore, the initial pre-added water volume for: Step S4: Online humidity detection and PID feedback water replenishment adjustment After the initial water addition was completed and the mixture was stirred for 15 seconds, the online measurement was performed. Lower than the target moisture content =15.0%, indicating that although pre-watering has been completed, the material's water absorption, diffusion, and local agglomeration have not yet reached complete equilibrium, therefore water replenishment is still required. Thus, the central controller enters the PID feedback water replenishment stage.

[0142] Then iterate second by second using the following formula: in, in, , , These are the proportional coefficient, integral coefficient, and differential coefficient, respectively. The mathematical meanings and specific functions of each sub-item are shown in Table 6.

[0143] Table 6 This embodiment takes =6.0g / % =4.0g / % =0.5g / %, when When the execution dead zone is exceeded, the central controller controls the liquid metering pump to add the corresponding amount of water; when When the moisture content is less than or equal to the execution dead zone, the liquid metering pump will not operate. If the actual moisture content continuously exceeds the upper limit of the target moisture content, the central controller will issue an alarm signal and prompt the addition of a trace amount of dry material or the preparation of the batch of mixture again.

[0144] In this embodiment, the original sampling frequency of the online humidity detection unit is 25Hz. The central controller performs a 1-second moving average processing on the original humidity signal and... =1s as the sampling period for PID control. Target moisture content. The target moisture content is 15.0%, with an allowable error. The allowable moisture content range is set to 0.3%, meaning the allowable moisture content control range is 14.7% to 15.3%.

[0145] Regarding the PID parameter selection in this embodiment =6.0g / % =4.0g / % =0.5g / %, further general PID parameter tuning is as follows: This embodiment serves as the benchmark calibration condition for the method of the present invention, used to determine the benchmark parameters used for subsequent PID parameter conversion under different material masses, target moisture content, and stirring speed conditions.

[0146] In this embodiment, the dry weight of the raw materials =2760g, target moisture content =15.0%, stirring speed =60rpm. Therefore, the operating condition in this embodiment is taken as the baseline operating condition, denoted as: After initial pre-water addition and homogenization, the central controller tunes the PID parameters under the baseline operating condition through a step water replenishment response test. This is based on the total target water addition volume. =263.1g and maximum amount of water to replenish at one time =15g, step water replenishment Determine using the following formula: Substitution =15g =263.1g, therefore: The central controller directs the liquid metering pump to add 5.26g of step-addition water to the mixture while continuing stirring. The online humidity detection unit records the change in the mixture's moisture content before and after the water addition. The difference in stable moisture content before and after the step-addition water addition is measured. Approximately 0.13 percentage points. Therefore, the unit moisture content response water of the mixture under the baseline operating condition is... for: in, This indicates the amount of water required to change the moisture content of the mixture by 1 percentage point under the baseline operating conditions.

[0147] According to the PID parameter tuning rules in the technical solution, the proportional tuning coefficient is selected. =0.15, integral tuning coefficient =0.10, differential integration coefficient =0.012, then: To facilitate central controller access and subsequent parameter conversion under different operating conditions, this embodiment rounds the above tuning result to: =6.0g / % =4.0g / % =0.5g / % The above , and That is, the present invention under the reference operating conditions , The baseline PID parameters were obtained through a step-water replenishment response test under the given conditions. In subsequent embodiments, when the raw material dry weight, target moisture content, or stirring speed changes, the central controller uses the parameters obtained in this embodiment. , and Use this as a benchmark for proportional conversion or recommended range verification.

[0148] The following explains the PID output boundary handling and water replenishment execution: Furthermore, in this embodiment, the water replenishment execution dead zone... Set to 0.10g, maximum amount for a single water replenishment. Set to 15g. The central controller obtains the theoretical water replenishment increment calculated by the PID algorithm. Then, it is first processed to be nonnegative. That is, when Δu(k) is positive, this value is retained as the nonnegative water replenishment amount. ;when When the value is zero or negative, it is truncated to 0, resulting in =0. Through this processing, this embodiment is limited to a control mode of "only replenishing water, not draining water", that is, the central controller only controls the liquid metering pump to replenish water in the positive direction, and does not perform drainage or pumping operations.

[0149] Subsequently, the central controller executes the dead zone based on the water replenishment. and the maximum amount of water replenished at one time Determine the actual amount of water to be replenished. .when When the amount of water added is less than or equal to 0.10g, the central controller determines that the water replenishment command is too small, and the liquid metering pump does not operate. =0; when When the amount is greater than 0.10g and less than or equal to 15g, the liquid metering pump shall be used according to... Water replenishment is performed based on the corresponding water volume; when When the amount exceeds 15g, the central controller will limit the actual amount of water added at one time to 15g to avoid excessive water addition leading to localized over-wetting of the mixture or over-adjustment of the moisture content.

[0150] In the PID water replenishment process of this embodiment, the theoretical water replenishment increment calculated by the PID at the 12th sampling is -0.04g. Since this value is negative, the central controller first truncates it to 0, i.e. Therefore, the liquid metering pump does not operate, and the actual water replenishment amount is 0g. Meanwhile, in this embodiment, the maximum single water replenishment amount calculated by the PID is 12.60g, which does not exceed the single water replenishment limit of 15g, therefore the single water replenishment limit protection is not triggered.

[0151] Furthermore, in this embodiment, the continuous over-limit determination time... Set to 5s, sampling period The time limit is 1 second, therefore the number of consecutive out-of-limit checks is: That is, when the actual moisture content is higher than the standard for five consecutive sampling periods. When the concentration exceeds 0.3%, the central controller determines that the mixture is in a continuously over-wet state, issues an alarm signal, and prompts the operator to add a trace amount of dry material or prepare the batch of mixture again. If only a single or short-term exceedance occurs, the central controller will not immediately issue an alarm, but will stop adding water and continue stirring and homogenizing.

[0152] The calculation results are shown in Table 7: Table 7 This set of values ​​clearly demonstrates the effectiveness of the formula and control strategy: feedforward pre-watering rapidly pushes the system to 13.80%, followed by multiple small pulse water replenishments via PID control, ultimately reaching a total water addition of 261.76g, very close to the previously calculated target value of 263.16g. Finally, online detection shows the moisture content stabilizes at around 14.95%, meeting the target moisture content control requirement of 15.0% ± 0.3%. Therefore, this invention's adaptive water addition system, through a control process of "theoretical water addition calculation—empirical compensation correction—pre-watering—online PID water replenishment," gradually brings the mixture moisture content closer to and stabilizes it near the target moisture content.

[0153] Step S5: Associate data records with batches When the actual moisture content of the mixture Stabilize at the target moisture content Once the allowable error range is reached, the central controller automatically generates a unique batch number for that batch of mixture and records the total wet mass of the raw materials for that batch. Initial moisture content Target moisture content Raw material dry weight Theoretical water addition Raw material characteristic compensation item Environmental evaporation compensation coefficient Process loss compensation item Initial experience compensation amount Final experience compensation amount Total target water addition Actual pre-added water ratio Initial pre-filled water volume Real-time moisture content at each sampling time Moisture content deviation PID water replenishment increment Actual water replenishment volume The cumulative water replenishment, ambient temperature, ambient humidity, and final stable moisture content are recorded and stored.

[0154] The central controller correlates the aforementioned water addition control data with the molding parameters, curing parameters, and subsequent performance test results of the corresponding batch of brick blanks to form a complete process data record for that batch of slag-fired non-fired bricks; and based on the process data from multiple batches, it adjusts... , , , Alternatively, provide a basis for review or suggestions for correction of the PID control parameters.

[0155] Furthermore, to verify the accuracy of the online moisture content detection results, this embodiment took samples from a location near the online moisture detection unit after stirring, and three 100g parallel samples were dried for verification. The moisture contents of the three parallel samples were 14.93%, 14.98%, and 14.96%, respectively, with an average of 14.96% and a maximum difference of 0.05%, which is less than 0.3%. This indicates that the online detection results for this batch are consistent with the drying verification results and can be used as valid data for database entry. After 7 days of curing, the compressive strength of the ordinary engineering slag non-fired brick specimens prepared in this embodiment was 13.10 MPa, with a standard deviation of 0.60 MPa and a coefficient of variation of 4.6%.

[0156] Example 2: Adaptive water control under sandy soil conditions The raw material characteristic compensation item is determined to be a lower value or a negative value based on the low clay content, low methylene blue value and low water absorption rate of sandy slag, and the method of avoiding the excessive pre-added water volume caused by using the compensation parameters of ordinary engineering slag for low water demand raw materials can be specifically explained through this embodiment.

[0157] In this embodiment, the clay mineral content of the sandy slag is 6.5% (less than 10%), the methylene blue value is 0.8 g / 100g dry soil (less than 1.0), and the water absorption rate per minute is 16 g / (kg·min) (less than 20). All three indicators fall into the sandy slag category, and the judgment is consistent. The unit dry material raw material characteristic compensation coefficient is taken as -1.99 g / kg dry material, and the raw material characteristic compensation item is -5.50 g. If the three indicators are not in the same category, the water absorption rate per minute is used as the priority criterion and is checked in conjunction with the methylene blue value MBV. If the water absorption rate per minute exceeds 120 g / (kg·min) or the MBV is greater than 6.0 g / 100g dry soil, the raw material characteristic compensation item is limited to the preset raw material characteristic compensation upper limit of 12 g / kg dry material, and the operator is prompted to separately calibrate the raw material or adjust the initial pre-added water amount.

[0158] See Figure 5 The composition of the sandy slag used in this embodiment was determined by sieving, laser particle size analysis, and semi-quantitative X-ray diffraction analysis. By particle size, sand accounted for approximately 72%, silt for approximately 21.5%, and clay for approximately 6.5%. By major mineral composition, quartz accounted for approximately 68%, feldspar for approximately 15%, calcite for approximately 5%, and clay minerals for approximately 6.5%, with the remainder being small amounts of mica, iron oxides, and amorphous components. The raw material had a methylene blue value (MBV) of 0.8 g / 100 g dry soil and a water absorption rate (A1) of 16 g / (kg·min), therefore it was determined to be sandy slag.

[0159] In this embodiment, the total wet mass of the raw materials =3000g, initial moisture content =8.0%, target moisture content =15.0%, ambient temperature T=26℃, relative humidity RH=52%, stirring speed n=60rpm, control sampling period =1s.

[0160] The central controller calculates: Since the raw material is sandy slag, the unit dry material material characteristic compensation coefficient is... If -1.99 g / kg of dry material is taken, then: This embodiment uses the same ambient temperature, relative humidity, stirring equipment, stirring speed, and semi-open stirring state as Embodiment 1; therefore, the environmental evaporation compensation coefficient is... Using the values ​​obtained through single-point calibration in Example 1: =0.225g / (kg dry material·kPa·min) If this single-point calibration is not performed, the central controller can first interpolate the initial reference value of the environmental evaporation compensation coefficient based on the initial recommended matrix in the technical solution; subsequent batch data can be used to form a review record or adjustment suggestion for the environmental evaporation compensation coefficient, which can be used to update the environmental evaporation compensation coefficient under the corresponding operating conditions after confirmation by the operator.

[0161] Since this embodiment already has a single-point calibration value under the same working conditions, this calibration value is used preferentially for calculation. .

[0162] Under conditions of T=26℃ and RH=52%, the vapor pressure difference (VPD) is approximately 1.61 kPa, and the effective exposure time is... =3min, therefore the environmental evaporation compensation coefficient is: Since this embodiment uses the same liquid metering pump, spray pipeline, nozzle, mixing tank, mixing paddle, loading amount, mixing speed, mixing time, and discharge method as Embodiment 1, and the total target water addition is in the same medium water addition range as in Embodiment 1, the process loss compensation item follows the calibration results of Embodiment 1 under the same equipment operating conditions: =4.00g Therefore, the initial empirical compensation amount without boundary treatment is calculated: The unit dry material experience compensation amount is: This value falls within the range of -6 to 25 g / kg dry material, therefore: The total target water addition is: In this embodiment, the water replenishment execution dead zone The maximum amount is 0.10g, which is the maximum amount that can be added to a single water replenishment. It is 15g, therefore , .because =248.56g> Central controller The feedback water replenishment reserve is as follows: The initial pre-filled water volume is: The PID parameters were obtained by tuning the step water replenishment response test under the baseline condition of Example 1. =6.0g / % =4.0g / % =0.5g / %. Due to the nature of this embodiment , And n is consistent with the baseline operating condition of Example 1, therefore =1, the central controller directly adopts: =6.0g / % =4.0g / % =0.5g / %.

[0163] Online PID feedback water replenishment resulted in a cumulative water replenishment of 24.35g, bringing the final total water addition to 248.05g. The online humidity detection unit measured a final stable moisture content of 15.02%. After drying and verification, the moisture contents of the three samples were 14.97%, 15.01%, and 14.99%, respectively, with an average moisture content of 14.99%. After 7 days of curing, the compressive strength of the sandy slag unfired brick specimens prepared in this embodiment was 12.85MPa, with a standard deviation of 0.66MPa and a coefficient of variation of 5.1%.

[0164] Therefore, it can be seen that the method of the present invention can effectively treat low-absorption sandy soil. Negative compensation reduces the total target water addition, and PID feedback water replenishment stabilizes the endpoint moisture content within the target range.

[0165] Example 3: Adaptive water injection control under high-viscosity shield tunneling sludge conditions: The raw material characteristic compensation item is determined to be a relatively high positive value based on the high viscosity of shield tunnel sludge, high clay content, high methylene blue value, and high water absorption rate. The method of pre-compensating for the water absorption lag of high water-demand raw materials and the tendency to be dry in the early stage of mixing can be specifically explained through this embodiment.

[0166] In this embodiment, the clay mineral content of the high-viscosity shield tunnel sludge is 31.5% (greater than 25%), the methylene blue value is 4.6 g / 100g dry soil (greater than 3.5), and the water absorption rate per minute is 78 g / (kg·min) (greater than 60). All three indicators fall into the category of high-viscosity slag, and the material characteristic compensation coefficient is determined to be a higher positive value within the range of 5–12 g / kg dry material. Considering the characteristics of this embodiment—high water absorption, easy agglomeration in the initial mixing stage, and localized dryness—the material characteristic compensation coefficient is... Take 10g / kg of dry material, raw material characteristic compensation item The value is 26.40g. If the three indicators are inconsistent, the water absorption rate per minute will be used as the priority criterion and will be verified in conjunction with the methylene blue value (MBV). If the water absorption rate per minute exceeds 120g / (kg·min) or the MBV is greater than 6.0g / 100g dry soil, the raw material characteristic compensation item will be limited to the preset upper limit of raw material characteristic compensation, 12g / kg dry material, and the operator will be prompted to calibrate the raw material separately or adjust the initial pre-added water amount.

[0167] This embodiment illustrates the use of high-viscosity shield tunnel sludge as raw material and the material characteristic compensation item. When taking the high value range, the method of the present invention can increase the amount of compensation water based on the characteristics of high viscosity raw materials with strong water absorption capacity and obvious water absorption lag, and avoid excessive water addition at one time through PID feedback water replenishment.

[0168] The composition of the high-viscosity shield tunneling sludge used in this embodiment was determined by sieving, laser particle size analysis, and semi-quantitative X-ray diffraction analysis. By particle size, sand accounted for approximately 18%, silt for approximately 50.5%, and clay for approximately 31.5%. By major mineral composition, quartz accounted for approximately 32%, feldspar for approximately 9%, calcite for approximately 8%, clay minerals for approximately 31.5%, and organic matter and amorphous components for approximately 19.5%. The clay minerals mainly included illite, montmorillonite, kaolinite, and chlorite. The raw material had a methylene blue value (MBV) of 4.6 g / 100 g dry soil and a water absorption rate (A1) of 78 g / (kg·min), therefore it was identified as high-viscosity shield tunneling sludge.

[0169] In this embodiment, the total wet mass of the raw materials =3000g, initial moisture content =12.0%, target moisture content =16.0%, ambient temperature T=26℃, relative humidity RH=52%, stirring speed n=60rpm.

[0170] The central controller calculates: Compensation coefficient for unit dry material properties of high-viscosity shield tunnel sludge If we take 10.00 g / kg of dry material, then: This embodiment uses the same ambient temperature, relative humidity, stirring equipment, stirring speed, and semi-open stirring state as Embodiment 1; therefore, the environmental evaporation compensation coefficient is... The value of 0.225 g / (kg dry material·kPa·min) obtained through single-point calibration in Example 1 is retained. The difference from Example 1 is that the dry weight of the raw material in this example... The amount is 2640g, therefore the environmental evaporation compensation coefficient is... Recalculate based on the dry weight of the current batch of raw materials, instead of directly using the formula from Example 1. Numerical value. Under conditions of T=26℃ and RH=52%, VPD≈1.61kPa. =3min, therefore: This embodiment uses the same liquid metering pump, spray system, stirring unit, and discharge method as Embodiment 1, and the calibrated water addition is still in the medium water addition range of approximately 150-250g. Therefore, the process loss compensation item adopts the calibration value under the same equipment operating conditions: =4.00g.

[0171] Therefore, the following calculation is performed: The unit dry material experience compensation amount is: This value falls within the range of -6 to 25 g / kg dry material, therefore: The total target water addition is: In this embodiment, =176.13g> Central controller The feedback water replenishment reserve is as follows: The initial pre-filled water volume is: The PID parameters are converted based on the parameters obtained from the baseline operating condition tuning in Example 1. In this example, =2640 / 2760, =16.0%, =15.0%, n=60rpm, =1. The central controller, after conversion and verification, takes: =5.9g / % =3.9g / % =0.49g / %.

[0172] The above parameters are within the recommended verification range for the corresponding material mass. After PID feedback water replenishment, the cumulative PID water replenishment amount was 17.05g, and the final cumulative total water added was 175.57g. The online humidity detection unit measured the final stable moisture content to be 15.96%; the moisture contents of the three samples after drying were 15.92%, 15.95%, and 15.96%, respectively, with an average moisture content of 15.94%. After 7 days of curing, the compressive strength of the high-viscosity shield tunnel sludge unfired brick specimens prepared in this embodiment was 12.70MPa, with a standard deviation of 0.72MPa and a coefficient of variation of 5.7%.

[0173] Therefore, it can be seen that for highly viscous and highly absorbent raw materials, the method of the present invention can improve... Compensation and PID-based phased water replenishment are used to avoid the mixture being too dry in the early stages and excessive water replenishment in the later stages.

[0174] Example 4: Adaptive water supply control under extreme environmental conditions: The method for determining the above-mentioned environmental evaporation compensation item based on environmental temperature, environmental relative humidity, water vapor pressure difference, effective exposure time, and environmental evaporation compensation coefficient can be specifically illustrated through this embodiment.

[0175] In this embodiment, under high temperature and low humidity conditions, the ambient temperature is 35℃ and the relative humidity is 30%. The calculated vapor pressure difference (VPD) is approximately 3.94 kPa. The effective exposure time is 3 min (under semi-open stirring conditions, the stirring time is taken from the initial pre-addition of water until the moisture content of the mixture meets the stability judgment condition). The environmental evaporation compensation coefficient is determined to be 0.261 g / (kg dry material·kPa·min) through environmental evaporation calibration test. Based on this, the environmental evaporation compensation term is calculated to be 8.50 g. Under low temperature and high humidity conditions, the ambient temperature is 10℃ and the relative humidity is 90%. The VPD is approximately 0.12 kPa. The environmental evaporation compensation coefficient is taken as 0.15 g / (kg dry material·kPa·min), and the environmental evaporation compensation term is 0.15 g.

[0176] This embodiment uses the same ordinary engineering waste soil as in Example 1. By particle size, the waste soil contains approximately 42% sand, 39% silt, and 19% clay. By major mineral composition, it contains approximately 46% quartz, 14% feldspar, 7% calcite, and 18.6% clay minerals, with the remainder being small amounts of mica, iron oxides, organic matter, and amorphous components. The raw material has a methylene blue value (MBV) of 2.4 g / 100g dry soil and a water absorption rate (A1) of 46 g / (kg·min), classifying it as ordinary engineering waste soil.

[0177] In this embodiment, the total wet mass of the raw materials =3000g, initial moisture content =8.0%, target moisture content =15.0%, raw material dry weight =2760g, theoretical water addition =247.06g, raw material characteristic compensation item =9.10g, process loss compensation item =4.00g. The PID parameters are the same as those used in Example 1 under the baseline operating condition. =6.0g / % =4.0g / % =0.5g / %.

[0178] High temperature and low humidity conditions: Under high temperature and low humidity conditions, with an ambient temperature of 35℃ and a relative humidity of 30%, the effective exposure time is... =3min. Based on the water vapor pressure difference formula, VPD≈3.94kPa is calculated.

[0179] Under these temperature and humidity conditions, the central controller can first... The initial recommendation matrix is ​​interpolated. Since T=35℃ falls between 30℃ and 40℃, and RH=30% corresponds to the relative humidity value in the recommendation matrix, the interpolation yields... The initial reference value is approximately 0.27 g / (kg dry material·kPa·min). Furthermore, after completing the single-point calibration under these high temperature and low humidity conditions, the central controller preferentially uses the single-point calibration value as the final value of the environmental evaporation compensation coefficient under the current operating conditions.

[0180] In this operating condition, the environmental evaporation compensation coefficient was determined to be 0.261 g / (kg dry material·kPa·min) through single-point calibration. Therefore, the central controller uses 0.261 g / (kg dry material·kPa·min) to calculate the environmental evaporation compensation term.

[0181] therefore: Since this operating condition only changes the ambient temperature and humidity, the liquid metering pump, spray pipeline, nozzles, mixing tank, mixing paddle, loading rate, mixing speed, and discharge method are all the same as in Example 1. Therefore, the process loss compensation item follows the calibration results of Example 1: =4.00g.

[0182] Therefore, the following calculation is performed: This value is within the limit range, therefore The total target water addition is: In this embodiment, = g> Central controller The feedback water replenishment reserve is: The initial pre-filled water volume is: Subsequently, PID feedback water replenishment was performed, with a cumulative water replenishment of 26.20g, bringing the final total water addition to 267.99g. The online humidity detection unit measured a final stable moisture content of 14.98%, and the average moisture content verified after drying was 14.97%. After 7 days of curing, the mean compressive strength of the specimens under this condition was 13.00MPa, with a standard deviation of 0.68MPa and a coefficient of variation of 5.2%.

[0183] Low temperature and high humidity conditions: Under low temperature and high humidity conditions, with an ambient temperature of 10℃ and a relative humidity of 90%, the effective exposure time is... =3min. Based on the water vapor pressure difference formula, VPD≈0.12kPa is calculated.

[0184] Under these temperature and humidity conditions, the central controller... The initial recommendation matrix is: =0.15g / (kg dry matter·kPa·min) Because the VPD is low and the environmental evaporation loss is small under these conditions, and the VPD is not less than 0.10 kPa, the central controller operates at the lowest setting. Calculate the environmental evaporation compensation coefficient: therefore: Since this operating condition only changes the ambient temperature and humidity, the liquid metering pump, spray pipeline, nozzles, mixing tank, mixing paddle, loading rate, mixing speed, and discharge method are all the same as in Example 1. Therefore, the process loss compensation item follows the calibration results of Example 1: =4.00g Therefore, the following calculation is performed: This value is within the limit range, therefore =13.25g. The total target amount of water to be added is: Central controller The feedback water replenishment reserve is: The initial pre-filled water volume is: Subsequently, PID feedback water replenishment was performed, with a cumulative water replenishment of 25.55g, bringing the final total water addition to 259.83g. The online humidity detection unit measured a final stable moisture content of 15.00%, and the average moisture content verified after drying was 14.99%. After 7 days of curing, the mean compressive strength of the specimens under this condition was 13.05MPa, with a standard deviation of 0.63MPa and a coefficient of variation of 4.8%.

[0185] As can be seen from this embodiment, under high temperature and low humidity conditions The amount of water added increases significantly, and the total target water addition increases accordingly; under low temperature and high humidity conditions... The moisture content was significantly reduced, and the total target water addition was correspondingly reduced. Under both environmental conditions, the final moisture content remained stable within the target moisture content range of 15.0% ± 0.3%, indicating that the environmental temperature and humidity compensation model of this invention can effectively correct the influence of environmental evaporation differences on the final moisture content of the mixture.

[0186] Example 5: Adaptive water addition control under different batch material quality conditions The method of adjusting the initial pre-added water ratio in conjunction with the total target water addition, and setting a feedback water replenishment reserve to limit the initial pre-added water addition from not exceeding the difference between the total target water addition and the reserve, as well as the method of obtaining the proportional coefficient, integral coefficient, and derivative coefficient of the incremental digital PID control algorithm from the reference operating condition parameters based on the raw material dry weight, target moisture content, and stirring speed, can all be specifically explained through this embodiment.

[0187] In this embodiment, the central controller adjusts the initial pre-filling ratio based on the relationship between the total target water addition Q and the preset water addition threshold. Adjustments will be made accordingly. Specifically, if the total target water addition Q is greater than or equal to the medium water addition threshold of 90g, the initial pre-added water ratio will be adjusted. Take 0.90; if the total target water addition Q is between the small water addition threshold of 30g and the medium water addition threshold of 90g, then the initial pre-addition water ratio is... Take 0.80; if the total target water addition Q is less than 30g, then the initial pre-added water ratio is... Further reduced to 0.60. For a small batch of 500g, the total target water addition Q is 44.40g, falling between 30g and 90g. Therefore, the initial pre-added water ratio... Take 0.80 as the feedback for water replenishment reserve. The amount is 3.55g, and the initial pre-added water volume is... The initial water addition is 35.52g; for a large-scale production of 5000g, the total target water addition Q is 436.94g, which is greater than 90g, therefore the initial pre-added water ratio is... Take 0.90 as the feedback for water replenishment reserve. The amount is 34.96g, and the initial pre-added water volume is... The amount is 393.25g. Therefore, this embodiment can adjust the initial pre-added water ratio according to the total target water volume, and by providing feedback on the water replenishment reserve, it can balance the over-humidity prevention requirements for small-batch operations with the water replenishment efficiency requirements for large-batch operations.

[0188] Furthermore, in this embodiment, for both the 500g small-batch and 5000g large-batch conditions, the baseline PID parameters tuned by the aforementioned step water replenishment response test are used as the basis. The parameters are proportionally converted based on the control parameters under the baseline condition, combined with the current batch's raw material dry weight, target moisture content, and stirring speed. For the 500g small-batch condition, the converted PID control parameters are: =1.00g / % =0.67g / % =0.08g / %; For a large-volume operation of 5000g, the calculated PID control parameters are as follows: =10.00g / % =6.67g / % =0.83g / %. The above conversion results have been verified by checking the recommended value range of PID parameters under the corresponding material mass range, which is in line with the determination method of obtaining PID control parameters by converting the reference operating condition parameters.

[0189] This embodiment uses the same type of ordinary engineering waste soil as in Example 1. By particle size, the waste soil contains approximately 42% sand, 39% silt, and 19% clay. By major mineral composition, it contains approximately 46% quartz, 14% feldspar, 7% calcite, and 18.6% clay minerals, with the remainder being small amounts of mica, iron oxides, organic matter, and amorphous components. The raw material has a methylene blue value (MBV) of 2.4 g / 100g dry soil and a water absorption rate (A1) of 46 g / (kg·min), classifying it as ordinary engineering waste soil.

[0190] In this embodiment, the initial moisture content =8.0%, target moisture content =15.0%, ambient temperature T=26℃, relative humidity RH=52%, stirring speed n=60rpm, water replenishment dead zone =0.10g, maximum amount of water to replenish in a single dose =15g. Since this embodiment examines the impact of different batch material qualities on the control process, a 500g small batch condition and a 5000g large batch condition are set up respectively.

[0191] This embodiment uses the same ambient temperature, relative humidity, and stirring equipment as Embodiment 1; therefore, the environmental evaporation compensation coefficient is the same. Using the values ​​obtained through single-point calibration in Example 1, i.e. =0.225 g / (kg dry material·kPa·min). Since this embodiment examines the impact of different batch sizes of material on the control process, Instead of directly using 3.00g from Example 1, the dry weight of the raw material under the current operating conditions is used. Calculate separately; simultaneously, due to significant changes in the charge amount and total target water addition, the process loss compensation item... Recalibrate separately for low and high water addition levels.

[0192] Small batch 500g working condition: When the total wet mass of a single batch of raw materials =500g: Ordinary construction waste If we take 3.30 g / kg of dry material, then: This operating condition uses the same environmental conditions as in Example 1. =0.225g / (kg dry matter·kPa·min), VPD≈1.61kPa, =3min, therefore: Since the batch material quality and total target water addition in this operating condition are significantly lower than in Example 1, the central controller uses the equipment process calibration results under the low water addition level to determine the process. During calibration, the same loading rate, stirring speed, spraying method, and discharge method as in this operating condition were used. The calibration command for adding water was approximately 40-45g. The process compensation amounts obtained from the three calibrations were 1.10g, 1.20g, and 1.30g, respectively. The average value was taken. =1.20g.

[0193] Therefore, the following calculation is performed: The unit dry material experience compensation amount is: This value is within the limit range, therefore =3.22g. The total target amount of water to be added is: because =44.40g, which meets the requirements. ≤ < Therefore, the central controller automatically adjusts the actual pre-added water ratio, taking... The feedback water replenishment reserve is as follows: The initial pre-filled water volume is: Under this operating condition, the PID parameters are converted based on the baseline PID parameters obtained in Example 1. Because =460 / 2760, = =15.0%, n=n0=60rpm, =1, therefore: The above parameters fall within the recommended verification range corresponding to a material mass of 500–1000g. After PID feedback-based water replenishment, the cumulative water replenishment amount was 8.55g, bringing the final total water addition to 44.07g. The online humidity detection unit measured a final stable moisture content of 15.05%, and the average moisture content after drying verification was 15.02%. After 7 days of curing, the mean compressive strength of the specimens under these conditions was 12.95MPa, with a standard deviation of 0.70MPa and a coefficient of variation of 5.4%.

[0194] Large-volume 5000g operation: When the total wet mass of raw materials in a single batch is M=5000g: Ordinary construction waste If we take 3.30 g / kg of dry material, then: This operating condition uses the same environmental conditions as in Example 1. =0.225g / (kg dry matter·kPa·min), VPD≈1.61kPa, =3min, therefore: Since the batch material quality and total target water addition in this operating condition are significantly higher than in Example 1, the central controller uses the equipment process calibration results under the high water addition level to determine the process. During calibration, the same loading rate, stirring speed, spraying method, and discharge method as in this operating condition were used. The calibration command for adding water was approximately 420–440 g. The process compensation amounts obtained from the three calibrations were 4.80 g, 5.00 g, and 5.20 g, respectively. The average value was taken. =5.00g Therefore, the following calculation is performed: The unit dry material experience compensation amount is: This value is within the limit range, therefore =25.18g. The total target amount of water to be added is: because =436.94g, greater than Therefore, the central controller takes The feedback water replenishment reserve is as follows: The initial pre-filled water volume is: Under this operating condition, the PID parameters are converted based on the baseline PID parameters obtained in Example 1. Because =4600 / 2760, = =15.0%, n=n0=60rpm, =1, therefore: The above parameters fall within the recommended verification range corresponding to a material mass of 3000–5000 g. After PID feedback-based water replenishment, the cumulative water replenishment amount was 42.85 g, bringing the final total water addition to 436.10 g. The online humidity detection unit measured a final stable moisture content of 14.97%, and the average moisture content after drying verification was 14.99%. After 7 days of curing, the mean compressive strength of the specimens under this condition was 13.15 MPa, with a standard deviation of 0.62 MPa and a coefficient of variation of 4.7%.

[0195] This embodiment demonstrates that when the mass of a single batch of material increases from 500g to 5000g, the method of the present invention can achieve the same result as the dry weight of the raw material. The compensation amount and PID parameters are proportionally corrected, and then... Linkage adjustment and The reserved mechanism avoids excessive pre-addition of water in small-batch operation conditions, while ensuring sufficient water replenishment response in large-batch operation conditions.

[0196] The key results of Examples 2 to 5 are summarized below: As demonstrated in Examples 2 to 5, the method of the present invention can dynamically adjust the amount of water added based on the particle composition, mineral composition, water absorption characteristics, environmental conditions, process losses, and online humidity feedback of raw materials under various conditions, including sandy slag, highly viscous shield tunnel sludge, high temperature and low humidity, low temperature and high humidity, and different batch material quality. This ensures that the final moisture content of the mixture is stably controlled within the allowable error range of the target moisture content. The above examples further illustrate that the present invention is not only applicable to single ordinary engineering slag or single environmental conditions, but can cover typical boundary conditions and extreme conditions across a wide range.

[0197] Comparative Example 1: Manual Water Addition Method To verify the effectiveness of the adaptive water addition control method compared to the existing manual water addition method, Comparative Example 1 is provided below. This comparative example uses the exact same raw materials as Example 1 (ordinary engineering waste soil, total wet mass = 3000g, initial moisture content = 8.0%, target moisture content = 15.0%), mixing equipment, mixing speed, pressing conditions, and curing conditions. However, the aforementioned empirical compensation, pre-water addition ratio linkage adjustment, incremental digital PID feedback water addition control, and PID output boundary processing are eliminated. The operator simply adds an estimated amount of water to the mixture based on experience. By comparing the two sets of moisture content change curves with mixing time and the 7-day compressive strength test results, the beneficial effects of this invention in terms of moisture content control accuracy, brick forming stability, and strength consistency are verified.

[0198] Furthermore, to verify the technical effect of the method of the present invention, the same pre-homogenized engineering waste soil as in Example 1 was used as raw material, and the total wet mass, initial moisture content, target moisture content, mixing conditions, pressing conditions, and curing conditions of the raw material were kept consistent. The difference is that Comparative Example 1 used a manual, experience-based water addition method, without introducing an empirical compensation amount. It does not employ online humidity feedback control, nor does it perform PID micro-water replenishment.

[0199] Specifically, operators add an estimated amount of water to the mixture in one go based on routine experience and the target moisture content, followed by stirring. The online humidity detection unit is only used to record changes in the moisture content of the mixture and does not participate in water addition control.

[0200] In this artificially induced water addition group, the change in the moisture content of the mixture with stirring time is shown in the attached figure. Figure 4 : The initial moisture content of the raw materials was 8.0% at the start of stirring; 13.2% after 10 seconds of stirring; 14.1% after 20 seconds of stirring; 15.6% after 30 seconds of stirring, exceeding the target moisture content of 15.0%; 16.1% after 40 seconds of stirring; and 15.8% and 15.6% after 50 and 60 seconds of stirring, respectively, still higher than the target moisture content.

[0201] In comparison, the moisture content of the adaptive water addition group of the present invention changes under the same time conditions as follows: 8.0% at the start of stirring; 13.6% after 10 seconds of stirring; 14.5% after 20 seconds of stirring; 14.9% after 30 seconds of stirring; 15.1% after 40 seconds of stirring; and it remains stable at around 15.0% after 50 and 60 seconds of stirring.

[0202] The results above show that the manual water addition group is prone to over-watering and moisture content overshooting due to the one-time water addition and lack of online feedback correction. In contrast, the adaptive water addition group of this invention combines initial pre-watering and PID micro-watering to gradually bring the moisture content close to the target value and stabilize it near the target moisture content in the later stage of mixing, thereby reducing the risks of wet mixture, sticking to the mold, and unstable molding.

[0203] Furthermore, 7-day compressive strength tests were conducted on the specimens prepared by the artificially induced water addition group and the adaptive water addition group of the present invention. A total of 24 batches of specimens were prepared for each group, and 3 specimens were randomly selected from each batch for 7-day compressive strength testing, thus obtaining a total of 72 strength test values ​​for each group. The summarized results are shown in Table 8: Table 8 Therefore, under the same raw materials, mixing conditions, pressing conditions, and curing conditions, the average 7-day compressive strength of the adaptive water addition group of this invention is about 5-10% higher than that of the artificially experienced water addition group, and the strength variation coefficient is reduced from 10.3% to 4.6%. This indicates that by improving the accuracy of moisture content control in the mixture, this invention improves the uniformity and density of brick forming, thereby increasing the early compressive strength of the test blocks and significantly reducing the strength dispersion between different batches of test blocks.

[0204] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. An adaptive water addition control method for the preparation process of laboratory slag non-fired bricks, applied to laboratory brick-making equipment, characterized in that, Includes the following steps: Obtain the total mass and initial moisture content of the raw materials, and calculate the dry weight of the raw materials based on the total mass and initial moisture content. The theoretical water addition is calculated based on the dry weight of the raw material, the target moisture content, and the initial moisture content, and the initial empirical compensation is calculated based on the raw material characteristic parameters, environmental evaporation parameters, and process loss parameters. The initial empirical compensation amount is subjected to boundary limiting processing to obtain the final empirical compensation amount. The total target water addition amount is calculated based on the theoretical water addition amount and the final empirical compensation amount. The initial pre-added water volume is determined based on the total target water volume, and the water addition execution unit is controlled to output the initial pre-added water volume to the stirring unit. When the stirring unit stirs the mixture, the online humidity detection unit is controlled to detect the actual moisture content of the mixture in real time; the water replenishment increment is calculated based on the deviation between the actual moisture content and the target moisture content, and the water addition execution unit is controlled to perform water replenishment until the deviation between the actual moisture content and the target moisture content is within the preset allowable error range; When the deviation between the actual moisture content and the target moisture content is within the preset allowable error range, the water addition control process data is recorded and stored.

2. The adaptive water addition control method for the laboratory slag non-fired brick preparation process according to claim 1, characterized in that, The determination of the final empirical compensation amount includes: applying the boundary limiting process to the initial empirical compensation amount to obtain the final empirical compensation amount; wherein, the initial empirical compensation amount includes raw material characteristic compensation item, environmental evaporation compensation item, and process loss compensation item; The boundary limiting process includes: converting the initial experience compensation amount into a unit dry material experience compensation amount, and comparing it with a preset lower limit and a preset upper limit; when the unit dry material experience compensation amount is lower than the preset lower limit, setting the unit dry material experience compensation amount as the preset lower limit; when the unit dry material experience compensation amount is higher than the preset upper limit, setting the unit dry material experience compensation amount as the preset upper limit; when the unit dry material experience compensation amount is not lower than the preset lower limit and not higher than the preset upper limit, keeping the unit dry material experience compensation amount unchanged. The final empirical compensation amount is calculated based on the unit dry material empirical compensation amount and the dry weight of the raw material; When the unit dry material experience compensation amount is lower than the preset lower limit or the unit dry material experience compensation amount is higher than the preset upper limit, an abnormal status is recorded and a review is prompted. When any of the following situations occur, a prompt will be made to re-perform raw material classification testing, environmental evaporation compensation coefficient calibration, or equipment process calibration: multiple consecutive batches show that the unit dry material experience compensation amount is lower than the preset lower limit; multiple consecutive batches show that the unit dry material experience compensation amount is higher than the preset upper limit; the difference between the initial experience compensation amount and the final experience compensation amount is greater than the preset recalibration trigger threshold.

3. The adaptive water addition control method for the laboratory slag non-fired brick preparation process according to claim 1, characterized in that, The step of determining the initial pre-added water volume based on the total target water volume includes: The initial pre-addition water ratio is adjusted according to the total target water addition amount, and the initial pre-addition water ratio decreases as the total target water addition amount decreases; the initial pre-addition water amount is determined by multiplying the adjusted initial pre-addition water ratio by the total target water addition amount.

4. The adaptive water addition control method for the laboratory slag non-fired brick preparation process according to claim 3, characterized in that, The method further includes: The feedback water replenishment reserve is determined based on the total target water addition, and the initial pre-added water amount does not exceed the difference between the total target water addition and the feedback water replenishment reserve. When the total target water addition is less than or equal to the feedback water replenishment reserve, or when the total target water addition is less than or equal to zero, the initial pre-added water amount is determined to be zero.

5. The adaptive water addition control method for the laboratory slag non-fired brick preparation process according to claim 1, characterized in that, The calculation of the water replenishment increment adopts an incremental digital PID control algorithm, which calculates the water replenishment increment for the current sampling period based on the moisture content deviation at the current sampling time, the moisture content deviation at the previous sampling time, and the moisture content deviation at the two previous sampling times. The proportional, integral, and derivative coefficients of the incremental digital PID control algorithm are obtained through step water replenishment response testing; or... The proportional coefficient, integral coefficient, and derivative coefficient of the incremental digital PID control algorithm are obtained by converting the parameters under the reference operating condition. The parameters are calculated based on the control parameters under the reference operating condition, combined with the dry weight of the raw material, the target moisture content, and the stirring speed of the current batch.

6. The adaptive water addition control method for the laboratory slag non-fired brick preparation process according to claim 5, characterized in that, The method further includes: performing output boundary processing on the water replenishment increment, specifically including: The water replenishment increment is nonnegated to obtain a nonnegative water replenishment amount. When the water replenishment increment is less than zero, the nonnegative water replenishment amount is zero. When the water replenishment increment is greater than or equal to zero, the nonnegative water replenishment amount is equal to the water replenishment increment. When the non-negative water replenishment amount is less than or equal to the preset water replenishment dead zone, the actual water replenishment amount is zero. When the non-negative water replenishment amount is greater than the preset water replenishment dead zone and the non-negative water replenishment amount is less than or equal to the preset single water replenishment limit, the actual water replenishment amount is equal to the non-negative water replenishment amount. When the non-negative water replenishment amount is greater than the preset single water replenishment limit, the actual water replenishment amount is equal to the preset single water replenishment limit.

7. The adaptive water addition control method for the laboratory slag non-fired brick preparation process according to claim 1, characterized in that, When the actual moisture content is higher than the upper limit of the target moisture content for multiple consecutive sampling cycles, and the number of consecutive sampling cycles required by the preset alarm conditions is reached, an alarm signal is issued and a prompt is made to add dry material or re-prepare the batch of mixture. When the actual moisture content is lower than the lower limit of the target moisture content, the water replenishment increment is calculated based on the deviation between the actual moisture content and the target moisture content, and water replenishment is performed. When the actual moisture content is higher than the upper limit of the target moisture content for multiple consecutive sampling cycles, but the number of consecutive sampling cycles required by the preset alarm condition is not reached, the water addition execution unit is controlled to stop adding water, and the stirring unit is controlled to continue stirring and homogenizing.

8. The adaptive water addition control method for the laboratory slag non-fired brick preparation process according to claim 2, characterized in that, The raw material characteristic compensation item is determined according to the type of slag raw material, which is classified according to one or more of the following three indicators: clay mineral content, methylene blue value and water absorption rate per minute. When the categories of slag raw materials obtained by determining the clay mineral content, the methylene blue value and the one-minute water absorption rate are inconsistent, the one-minute water absorption rate shall be used as the priority criterion and the methylene blue value shall be used for verification. When the water absorption rate per minute exceeds the preset high water absorption threshold, or the methylene blue value exceeds the preset high adsorption threshold, the raw material characteristic compensation item is limited to the preset upper limit value of raw material characteristic compensation, and the operator is prompted to individually calibrate the raw material or adjust the initial pre-added water amount.

9. The adaptive water addition control method for the laboratory slag non-fired brick preparation process according to claim 2, characterized in that, The environmental evaporation compensation term is determined based on the ambient temperature, ambient relative humidity, water vapor pressure difference, effective exposure time, and environmental evaporation compensation coefficient. The water vapor pressure difference is calculated based on the ambient temperature and the ambient relative humidity; The effective exposure time is determined according to the opening state of the stirring unit. Under open stirring conditions, the actual stirring time is taken. Under semi-open stirring conditions, the stirring time is taken from the initial pre-addition of water until the moisture content of the mixture meets the stability judgment condition. Under closed stirring conditions, it is calculated according to a preset ratio of the actual stirring time. The environmental evaporation compensation coefficient was obtained through an environmental evaporation calibration test. When the environmental evaporation calibration test under the current ambient temperature and relative humidity conditions has not been completed, the initial reference value of the environmental evaporation compensation coefficient is determined by linear interpolation or bilinear interpolation according to the preset recommended matrix of environmental evaporation compensation coefficient. When both the initial reference value and the single-point calibration value exist, the single-point calibration value shall be used preferentially.

10. The adaptive water addition control method for the laboratory slag non-fired brick preparation process according to claim 2, characterized in that, The process loss compensation item is determined through equipment process calibration tests. The calibration test of the equipment process uses calibration materials and is conducted under equipment and process conditions corresponding to the actual brick-making process. The calibration materials are dried standard quartz sand or pre-homogenized inert fine aggregate. During calibration, a calibration command for water addition is output. After stirring, the calibration materials are collected and the effective water volume is measured. The single process loss compensation is calculated based on the calibration command for water addition, the effective water volume, and the environmental evaporation loss during the calibration process. Multiple parallel calibrations are performed under the same equipment operating conditions. When the relative deviation of the multiple calibration results exceeds the preset deviation threshold, recalibration is performed. The average value of the multiple calibration results is taken as the process loss compensation item under the equipment operating conditions. When the process loss compensation item exceeds the preset abnormal range, check the liquid metering pump, pipeline, nozzle, mixing tank wall and discharge method, and recalibrate after maintenance; If the liquid metering pump, spray pipeline, nozzle, mixing tank, or mixing paddle is replaced, or if the actual loading volume, mixing speed, spraying method, or calibration conditions change, then recalibration should be performed.

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