A coal slime water dynamic concentration detection device and method

Abstract

The application provides a coal slime water dynamic concentration detection device and method, and belongs to the coal slime water dosing technical field; the hysteresis problem of concentration detection in the existing coal slime water concentration process is solved; the device comprises a motion execution mechanism and a data detection and acquisition module; the motion execution mechanism comprises a cross ball screw sliding table, a connecting rod and a laser ranging reference surface; the cross ball screw sliding table is installed on the side of a bridge; the X-axis direction of the cross ball screw sliding table is parallel to the bridge, and the Y-axis direction extends into a concentration tank; the connecting rod is vertically installed on the cross ball screw sliding table; the data detection and acquisition module comprises a concentration sensor, a laser ranging sensor and an upper computer; the laser ranging sensor and the laser ranging reference surface can cooperate with each other to realize real-time detection of the depth of the concentration sensor submerged into the concentration tank; the upper computer can obtain the concentration and the submerged depth at different depths of the clarified layer of the concentration tank according to the collected real-time data; and the application is applied to coal slime water dynamic concentration detection.

Description

Technical Field

[0001] This invention provides a device and method for detecting the dynamic concentration of coal slurry water, belonging to the field of coal slurry water dosing control technology. Background Technology

[0002] To ensure the smooth operation of the coal slurry thickening process, it is necessary to monitor the thickening effect. In coal preparation plants, the quality of coal slurry thickening is generally judged by the concentration of overflow water detected by sensors. These sensors are typically fixed at a single point. Using this single-point detection method for thickening effect monitoring often makes it difficult to predict the trend of overflow concentration changes; that is, it is difficult to determine the concentration change at the next moment from time t. This makes it difficult to control the concentration changes in the clear water layer of the thickener. Furthermore, when the overflow concentration at the detection point exceeds the set value, due to the large inertia of coal slurry thickening, it takes time for the feedback and adjustment of the dosage to return to stable conditions, resulting in a lag in control. Therefore, multi-point detection of the clarification layer in the thickener is necessary. Multi-point detection can be achieved by increasing the number of sensors and dynamic detection. However, due to the harsh operating environment, this would significantly reduce the lifespan of the sensors. Increasing the number of sensors for multi-point detection would undoubtedly increase the cost of coal preparation. Therefore, dynamic detection can be used to detect the concentration at different heights of the clarification layer in the thickener. Summary of the Invention

[0003] To address the lag problem in concentration detection during existing coal slurry water thickening processes, this invention proposes a dynamic concentration detection device and method for coal slurry water.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: a dynamic concentration detection device for coal slurry water, comprising a motion execution mechanism and a data detection and acquisition module. The motion execution mechanism includes a cross ball screw slide, a connecting rod, and a laser ranging reference surface. The cross ball screw slide is installed on the side of the bridge frame, with the mounting surface perpendicular to the forward direction. The X-axis of the cross ball screw slide is parallel to the bridge frame, and the Y-axis extends into the thickening tank. The connecting rod is vertically installed on the cross ball screw slide. The laser ranging reference surface is installed at the bottom of the bridge frame.

[0005] The data detection and acquisition module includes a concentration sensor, a laser rangefinder sensor, and a host computer. The concentration sensor is installed at the bottom of the connecting rod, and the laser rangefinder sensor is installed at the top of the connecting rod. By cooperating with the laser rangefinder reference plane, the depth of the concentration sensor submerged in the concentration tank can be detected in real time.

[0006] The laser rangefinder and concentration sensor are connected to the host computer via wires. The host computer can obtain the concentration at different depths of the clarification layer in the thickener and the corresponding diving depth based on the collected real-time data.

[0007] The concentration sensor specifically employs a diffused light concentration sensor to detect the overflow concentration.

[0008] The laser rangefinder and concentration sensor transmit the collected data to the host computer in real time via RS485 communication.

[0009] The connecting rod includes a bottom free end and a top free end that are parallel to each other. The bottom free end and the top free end are fixedly connected by a vertical rod. The bottom free end is fixed on the ball screw slide in the Y-axis direction of the cross ball screw slide and can move up and down with the cross ball screw slide.

[0010] The concentration sensor is fixed to the bottom free end of the connecting rod, and the laser rangefinder is fixed to the top free end of the connecting rod.

[0011] The host computer is equipped with a linear model for detecting the dynamic concentration of coal slurry water. The change in overflow concentration in the thickener can be determined based on the linear slope of the linear model and the linear slope of the critical dynamic concentration.

[0012] A method for detecting the dynamic concentration of coal slurry water, using a coal slurry water dynamic concentration detection device, is characterized by comprising the following steps:

[0013] Concentration in concentration tanks at different depths is measured in real time using concentration sensors and laser rangefinders.

[0014] A linear model was constructed based on the concentration values ​​at different depths and the time depth, where the time depth is the product of time and the diving depth of the concentration sensor;

[0015] The change in overflow concentration in the thickener can be determined by comparing the linear slope of the linear model with the linear slope of the critical dynamic concentration.

[0016] The change in overflow concentration in the thickener is determined by first comparing the slope of the linear model with the linear slope of the critical dynamic concentration, and then combining the concentration value detected by the dynamic concentration device at the current time depth position to predict the concentration effect according to the discrimination rules.

[0017] The linear model is a first-order linear model, and its expression is as follows:

[0018] y = ax + b ;

[0019] In the above formula: y These represent the concentration values ​​of the concentrate at different depths of the thickening tank. x Indicates time depth. a The slope is linear.b This represents the concentration value at the liquid surface in the thickener.

[0020] The linear slope of the critical dynamic concentration is obtained by classifying the overflow concentration into three levels: ≤500mg / L, 500mg / L~1500mg / L, and ≥1500mg / L, based on the national standard for wash water concentration. Then, the slope value at the critical value (1500mg / L) can be obtained according to the optimal dosage for an overflow concentration of 1500mg / L and the ExpAssoc model.

[0021] The optimal dosage was obtained by substituting the concentration value of 1500 mg / L into the Boltzmann model;

[0022] The Boltzmann model was derived by modeling based on the concentration values ​​of clarified water and the dosage values ​​of the chemical.

[0023] The ExpAssoc model is derived by nonlinearly fitting the optimal dosage and the linear slope at that dosage.

[0024] The advantages of this invention compared to existing technologies are as follows: By combining multiple sensors in multi-point detection into one, the cost of coal preparation is reduced. Furthermore, to meet the needs of multi-point detection, a mobile installation method is adopted. The mobility of the dynamic concentration detection device allows for the measurement of concentrations at different depths in the clarification layer of the coal slurry thickener, fully considering the concentration values ​​at different depths within the clarification layer and maintaining stable overflow concentration. Based on the slope of the detected concentration values ​​at different depths in the clarification layer over time, the trend of thickening effect can be predicted, thus constructing a dynamic concentration detection method. In this way, the dosing system can be controlled according to the changing trend of flocculation and sedimentation, overcoming the problems of control lag, unstable overflow concentration, and high cost caused by the inability of a single sensor to predict flocculation and sedimentation trends, and preventing the deterioration of circulating water. Attached Figure Description

[0025] The present invention will be further described below with reference to the accompanying drawings:

[0026] Figure 1 This is a schematic diagram of the overall structure of the device of the present invention;

[0027] Figure 2 This is a schematic diagram of the installation of the present invention on a thickening tank;

[0028] Figure 3 This is a particle size distribution diagram of the coal used in the example;

[0029] Figure 4 This is a schematic diagram of dynamic detection results and data fitting.

[0030] Figure 5A schematic diagram of the Boltzmann model derived from modeling data on clarified water concentration and dosage.

[0031] Figure 6 This is a schematic diagram illustrating the nonlinear fitting of linear slope and dosage.

[0032] In the diagram: 1 is the thickening tank, 2 is the rake frame, 3 is the central drive shaft, 4 is the bridge frame, 5 is the cross ball screw slide, 6 is the laser rangefinder sensor, 7 is the connecting rod, 8 is the laser rangefinder reference surface, 9 is the concentration sensor, and 10 is the host computer. Detailed Implementation

[0033] Traditional overflow water detection relies on fixed-installation sensors, which often struggle to predict overflow concentration trends. This makes it difficult to forecast concentration changes in the clear water layer of the thickener. Furthermore, in fixed-installation methods, adjusting the dosage only when the overflow concentration at the detection point exceeds a set value results in a regulatory lag. While increasing the number of sensors for multi-point detection is feasible, the harsh operating environment significantly reduces sensor lifespan, further increasing coal preparation costs. To address these issues, this invention proposes a dynamic concentration detection device for coal slurry water, such as… Figure 1 and Figure 2 The diagram shows the device composition of the present invention. Based on the existing thickener structure, the existing thickener 1 has a rake frame 2 at the bottom, which is driven to rotate by the central drive shaft 3. A motion execution mechanism and a data detection and acquisition module are added and interconnected. The motion execution mechanism includes a cross ball screw slide 5, a connecting rod 7, and a laser ranging reference surface 8. The ball screw slide 5 is installed on the side of the bridge frame 4, with the mounting surface perpendicular to the forward direction. The X-axis of the cross ball screw slide 5 is parallel to the bridge frame 4, and the Y-axis extends into the thickener 1. The connecting rod 7 is vertically installed on the cross ball screw slide 5. The laser ranging reference surface 8 is installed at the bottom of the bridge frame 4.

[0034] The data detection and acquisition module includes a concentration sensor 9, a laser rangefinder 6, and a host computer 10. The concentration sensor 9 is mounted on a connecting rod 7 connected to the cross ball screw slide 5. Due to the small overflow concentration, a diffused light concentration sensor 9 is used to detect the overflow concentration. Simultaneously, to detect the depth to which the concentration sensor 9 submerges, a laser rangefinder 6 is provided for the cross ball screw slide 5. The laser rangefinder 6 is connected to the cross ball screw slide 5 via the connecting rod 6. The laser rangefinder 6 and the laser ranging reference surface 8 work together to detect the depth to which the concentration sensor 9 submerges in the thickener 1 in real time. The data from the concentration sensor 9 and the laser rangefinder 6 are transmitted to the host computer 10 in real time via RS485 communication for data acquisition. Based on the acquired real-time data, the concentration at different depths of the clarification layer in the thickener and the corresponding submersion depth can be obtained.

[0035] In this embodiment of the invention, raw coal from a coal preparation plant in Anhui Province is selected, such as... Figure 3 As shown, the coal sample particle size D 50 =6.08mm, D 90 =18.40mm. To eliminate the influence of ions in the water on the sedimentation effect at different depths, deionized water was used to prepare the coal slurry water. The flocculant solution was prepared using cationic flocculant with a molecular weight of 8 million-10 million and a mass concentration of 1mg / ml.

[0036] like Figure 1 As shown, the thickener is a peripheral drive type. During operation, the bridge frame 4 rotates around the central drive shaft 3 under the drive of the motor, and the ball screw slide 5, mounted on the bridge frame 4, also moves horizontally. Coal slurry enters the central feed tank of the thickener 1 through a pipeline for buffering and dispersion. The coal slurry from the bottom of the central feed tank enters the thickener 1 and undergoes thickening and settling under gravity. Fixed overflow concentration detection involves installing a concentration sensor 9 on the overflow weir wall to detect the concentration of the clarified water. Dynamic concentration detection involves installing the concentration sensor 9 on the cross ball screw slide 5, which reciprocates along the y-axis. Figure 2 As shown, with the movement of the sliding table, the concentration sensor 9 and the laser rangefinder 6 move accordingly, as... Figure 1 As shown, two sensors are connected to the host computer 10 via RS485 and collect data during the movement of the sensors with the cross ball screw slide 5. This data includes the concentration values ​​at different depths and the depth of the sensor descent. A linear model is constructed based on the concentration values ​​at different depths and the time depth. The change in overflow concentration in the thickener can be determined by the linear slope of the linear model and the linear slope of the critical dynamic concentration. The time depth is the product of time and the descent depth of the concentration sensor.

[0037] The linear model is a first-order linear model, as shown in the equation:

[0038] y = ax + b ;

[0039] in, y These represent the concentration values ​​of the concentrate at different depths of the thickening tank. x Indicates time depth. a The slope is linear. b This represents the concentration value at the liquid surface in the thickener. The dynamic monitoring results and data fitting results of the coal slurry water obtained from the linear model are as follows: Figure 4 As shown.

[0040] The linear slope of the critical dynamic concentration is determined by classifying the overflow concentration into three levels: ≤500mg / L, 500mg / L~1500mg / L, and ≥1500mg / L, based on the national standard for wash water concentration. Then, the slope value at the critical value (1500mg / L) can be obtained according to the optimal dosage for an overflow concentration of 1500mg / L and the ExpAssoc model.

[0041] The optimal dosage was obtained by substituting the concentration value of 1500 mg / L into the Boltzmann model.

[0042] like Figure 5 As shown, the Boltzmann model is derived by modeling based on the concentration values ​​of clarified water and the dosage values ​​of the chemicals.

[0043] like Figure 6 As shown, the ExpAssoc model is derived by nonlinearly fitting the optimal dosage and the linear slope at that dosage.

[0044] As shown in Table 1 below, the change in overflow concentration in the thickener is determined by first comparing the slope of the linear model with the critical slope, and then combining this with the concentration value detected by the dynamic concentration device at the current time depth. Based on this, a judgment is made on the concentration effect according to the discrimination rules, such as a linear slope greater than 0 and less than the critical slope k. 1500 When the concentration is between 500 mg / L and 1500 mg / L, the concentration effect is poor according to the discrimination rule. At this time, the dosage needs to be increased appropriately. Similarly, when the concentration effect is good, the dosage needs to be reduced appropriately. When the concentration is 0, the dosage does not need to be adjusted.

[0045]

[0046] Table 1. Rules for predicting concentration effect.

[0047] Both the aforementioned sensors and the host computer can be commercially available products, as long as they meet the usage requirements of this invention. Since the cross-shaped ball screw slide is a non-standard part, its size needs to be customized according to the requirements and installation dimensions.

[0048] Regarding the specific structure of this invention, it should be noted that the connection relationships between the various component modules used in this invention are definite and achievable. Except as specifically described in the embodiments, their specific connection relationships can bring about corresponding technical effects and solve the technical problems proposed by this invention without relying on the execution of corresponding software programs. The models of the components, modules, and specific components appearing in this invention, the connection methods between them, and the conventional usage methods and expected technical effects brought about by the above technical features, unless specifically described, are all publicly disclosed content in patents, journal articles, technical manuals, technical dictionaries, and textbooks that can be obtained by those skilled in the art before the application date, or belong to conventional technology, common knowledge, and other existing technologies in this field. There is no need to elaborate, which makes the technical solution provided in this case clear, complete, and achievable, and can reproduce or obtain corresponding physical products based on this technical means.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dynamic concentration detection device for coal slurry water, characterized in that: The system includes a motion actuator and a data detection and acquisition module. The motion actuator includes a cross ball screw slide, a connecting rod, and a laser ranging reference surface. The cross ball screw slide is mounted on the side of the bridge frame with the mounting surface perpendicular to the forward direction. The X-axis of the cross ball screw slide is parallel to the bridge frame, and the Y-axis extends into the concentration tank. The connecting rod is vertically mounted on the cross ball screw slide. The laser ranging reference surface is mounted on the bottom of the bridge frame. The data detection and acquisition module includes a concentration sensor, a laser rangefinder sensor, and a host computer. The concentration sensor is installed at the bottom of the connecting rod, and the laser rangefinder sensor is installed at the top of the connecting rod. By cooperating with the laser rangefinder reference plane, the depth of the concentration sensor submerged in the concentration tank can be detected in real time. The laser rangefinder and concentration sensor are connected to the host computer via wires. The host computer can obtain the concentration at different depths of the clarification layer in the thickener and the corresponding diving depth based on the collected real-time data. The concentration sensor specifically employs a diffused light concentration sensor to detect the overflow concentration; The laser rangefinder and concentration sensor transmit the collected data to the host computer in real time via RS485 communication. The connecting rod includes a bottom free end and a top free end that are parallel to each other. The bottom free end and the top free end are fixedly connected by a vertical rod. The bottom free end is fixed on the ball screw slide in the Y-axis direction of the cross ball screw slide and can move up and down with the cross ball screw slide. The concentration sensor is fixed to the bottom free end of the connecting rod, and the laser rangefinder is fixed to the top free end of the connecting rod.

2. The dynamic concentration detection device for coal slurry water according to claim 1, characterized in that: The host computer is equipped with a linear model for detecting the dynamic concentration of coal slurry water. The change in overflow concentration in the thickener can be determined based on the linear slope of the linear model and the linear slope of the critical dynamic concentration.

3. A method for detecting the dynamic concentration of coal slurry water, using a coal slurry water dynamic concentration detection device as described in claim 1 or 2, characterized in that: Includes the following steps: Concentration in concentration tanks at different depths is measured in real time using concentration sensors and laser rangefinders. A linear model was constructed based on the concentration values ​​at different depths and the time depth, where the time depth is the product of time and the diving depth of the concentration sensor; The change in overflow concentration in the thickener can be determined by comparing the linear slope of the linear model with the linear slope of the critical dynamic concentration. The change in overflow concentration in the thickener is determined by first comparing the slope of the linear model with the linear slope of the critical dynamic concentration, and then combining the concentration value detected by the dynamic concentration device at the current time depth position to predict the concentration effect according to the discrimination rules.

4. The method for detecting the dynamic concentration of coal slurry water according to claim 3, characterized in that: The linear model is a first-order linear model, and its expression is as follows: y = ax + b ； In the above formula: y These represent the concentration values ​​of the concentrate at different depths of the thickening tank. x Indicates time depth. a The slope is linear. b This represents the concentration value at the liquid surface in the thickener.

5. The method for detecting the dynamic concentration of coal slurry water according to claim 4, characterized in that: The linear slope of the critical dynamic concentration is obtained by classifying the overflow concentration into three levels: ≤500mg / L, 500mg / L~1500mg / L, and ≥1500mg / L, based on the national standard for wash water concentration. Then, the slope value at the critical value (1500mg / L) can be obtained according to the optimal dosage for an overflow concentration of 1500mg / L and the ExpAssoc model.

6. The method for detecting the dynamic concentration of coal slurry water according to claim 5, characterized in that: The optimal dosage was obtained by substituting the concentration value of 1500 mg / L into the Boltzmann model; The Boltzmann model was derived by modeling based on the concentration values ​​of clarified water and the dosage values ​​of the chemical. The ExpAssoc model is derived by nonlinearly fitting the optimal dosage and the linear slope at that dosage.

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