Dust concentration on-line real-time measurement system and method for cement plant

Abstract

The invention discloses a dust concentration online real-time measuring system and method for a cement plant, and relates to the technical field of dust concentration measuration.The system comprises a measuring device body, a main control box, an optical fiber transmitting module and an optical fiber receiving module, the main control box is arranged on the measuring device body, and a main control circuit board is arranged in the main control box; the optical fiber transmitting module and the optical fiber receiving module are arranged below the main control box; the optical fiber transmitting module is used for transmitting optical signals to the internal space of the measuring device main body, and the optical fiber receiving module is used for receiving optical signals scattered by dust particles in the internal space of the measuring device main body; the environment of the internal space of the measuring device main body is consistent with that of a cement plant; the optical fiber receiving module converts the received optical signal into a voltage signal and transmits the voltage signal to a main control circuit board in the main control box; and the main control circuit board calculates the dust concentration in the cement plant according to the obtained voltage signal. The dust concentration can be continuously monitored in real time, and the timeliness and accuracy of dust concentration detection are improved.

Description

Technical Field

[0001] The invention relates to the technical field of dust concentration measurement, and in particular to an online real-time dust concentration measurement system and method for a cement plant. Background Art

[0002] Cement is one of the most important structural materials in buildings and an indispensable part of construction projects. Cement plants produce a lot of dust during the production process, such as the grinding system, cement kiln, dryer, packaging process, and transportation process. The dust concentration in the factory environment of most cement production enterprises exceeds the standard, and the dust is very harmful.

[0003] Dust concentration is the dust content per unit volume of air. There are two ways to express it: one is mass concentration, which is the number of milligrams of dust per cubic meter of air (mg / m 3 ). The other is particle concentration, which is the number of dust particles per cubic meter of air. At present, the direct measurement method is mainly used for the measurement of dust in cement plant workshop environment. Specifically, a certain volume of dust-laden air is passed through a filter membrane of known weight to retain dust on the filter membrane. The dust concentration can be calculated based on the weight difference of the filter membrane before and after sampling and the air sampling volume. This method is simple and easy to use with high accuracy. However, it also has some limitations, such as the need to spend a lot of time and manpower for sample collection and laboratory analysis, and the inability to achieve continuous real-time monitoring. Summary of the invention

[0004] In order to solve the above problems, the present invention provides an online real-time measurement system and method for dust concentration in a cement plant, which are used to realize continuous real-time monitoring of dust concentration and improve the timeliness and accuracy of dust concentration detection.

[0005] To achieve the above-mentioned purpose, the present invention provides an online real-time measurement system for dust concentration in a cement plant, comprising: a measuring device body, a main control box, an optical fiber transmitting module and an optical fiber receiving module, wherein the main control box is arranged on the measuring device body, a main control circuit board is arranged in the main control box, and the optical fiber transmitting module and the optical fiber receiving module are arranged below the main control box; the optical fiber transmitting module is used to transmit an optical signal to the internal space of the measuring device body, and the optical fiber receiving module is used to receive an optical signal scattered by dust particles in the internal space of the measuring device body; the optical fiber receiving module converts the received optical signal into a voltage signal and transmits it to the main control circuit board in the main control box; the main control circuit board calculates the dust concentration in the cement plant according to the obtained voltage signal.

[0006] To achieve the above-mentioned purpose, the present invention also provides an online real-time measurement method for dust concentration in a cement plant, which is applied to the above-mentioned online real-time measurement system for dust concentration in a cement plant, and comprises: transmitting an optical signal to the cement plant through an optical fiber transmitting module, and receiving the optical signal scattered by dust particles in the internal space of the measuring device body through an optical fiber receiving module, and converting the optical signal into a voltage signal; measuring the dust concentration of the cement plant in the internal environment of the simulated device by a membrane filter method, and measuring the corresponding voltage values ​​under different cement plant dust concentrations to determine the functional relationship between the cement plant dust concentration and the voltage value; based on the functional relationship between the cement plant dust concentration and the voltage value, calculating the dust concentration in the cement plant according to the voltage signal through the signal processing module in the main control circuit board.

[0007] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0008] In the present invention, when the ambient air of the cement plant enters the internal space of the measuring device body, the backscattered light of the cement plant dust is collected in real time, and the voltage signal is output by the photoelectric sensor element. The dust concentration is calculated by the main control circuit board, and the real-time and accurate detection of the ambient dust concentration of the cement plant is realized, thereby achieving the purpose of timely warning. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0010] Figure 1 This is a schematic diagram of the on-line real-time measurement system for dust concentration in cement plants;

[0011] Figure 2 This is a front view of the on-line real-time measurement system for dust concentration in cement plants;

[0012] Figure 3 It is a structural schematic diagram of an optical fiber transmitting module and an optical fiber receiving module;

[0013] Figure 4 is a schematic diagram of backscattered light intensity;

[0014] In the figure, 1-fan, 2-main control box, 3-optical fiber transmitting module, 4-optical fiber receiving module, 5-upper cover, 6-right cover, 7-right shaft, 8-right transmission shaft, 9-reduction motor, 10-left transmission shaft, 11, 12-fixed blocks, 13-front cover, 14-small cover on the front side of the main control circuit box, 15-main control circuit board, 16-wireless transmitting module, 17-left shaft, 18-left cover, 19-measuring device body, 20-battery module, 21-light source, 22-photoelectric sensor, 23-lens, 24-alarm, 25-optical fiber transmitting tube, 26-optical fiber receiving tube. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0016] The purpose of the present invention is to provide an online real-time measurement system and method for dust concentration in a cement plant, which can realize continuous real-time monitoring of dust concentration and improve the timeliness and accuracy of dust concentration detection.

[0017] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0018] Embodiment 1

[0019] like Figure 1 As shown, the on-line real-time measurement system for dust concentration in cement plants provided in this embodiment includes: a measuring device body 19, a main control box 2, an optical fiber transmitting module 3 and an optical fiber receiving module 4. The main control box 2 is arranged on the measuring device body 19, and the bottom of the main control box 2 is fixed by two fixing blocks 11 and 12. A main control circuit board 15 is arranged in the main control box 2, and the optical fiber transmitting module 3 and the optical fiber receiving module 4 are arranged below the main control box 2. The main control box 2 is also provided with a small cover plate 14 on the front side of the main control circuit box.

[0020] Furthermore, if Figure 1 and Figure 3 As shown, the optical fiber transmitting module 3 includes a light source 21 and an optical fiber transmitting tube 25, and the optical fiber receiving module 4 includes a photoelectric sensor 22 and an optical fiber receiving tube 26. The lower side of the optical fiber hole of the optical fiber transmitting module 3 and the optical fiber receiving module 4 is connected to a lens 23, and the lens 23 contacts the internal space of the measuring device body 19.

[0021] The upper end of the optical fiber transmitting tube 25 is processed with threads, and the upper end of the optical fiber transmitting tube 25 is connected to the upper cover plate 5. The upper end of the optical fiber receiving tube 26 is processed with threads, and a photoelectric sensor 22 is installed inside. The optical fiber receiving tube 4 mainly receives light backscattered by dust.

[0022] Further, the reduction motor 9 is fixed to the bottom of the measuring device body 17, and a left transmission shaft 10 is provided on the left side of the reduction motor 9, and the left transmission shaft 10 is driven when the reduction motor 9 rotates. A right transmission shaft 8 is provided on the right side of the reduction motor 9, and the right transmission shaft 8 is driven when the reduction motor 9 rotates.

[0023] like Figure 2 As shown, the measuring device body 19 is provided with an upper cover plate 5, a front cover plate 13, a left cover plate 18 and a right cover plate 6. The right cover plate 6 is provided with a right rotating shaft 7, and the right transmission shaft 8 drives the right rotating shaft 7 to rotate, thereby driving the right cover plate 6 to open or close. The left cover plate 18 is provided with a left rotating shaft 17, and the left transmission shaft 10 drives the left rotating shaft 17 to rotate, thereby driving the left cover plate 18 to open or close.

[0024] Furthermore, if Figure 1 As shown, a wireless transmission module 16 is also provided in the main control box 2 and connected to the signal processing module of the main control circuit board 15. When the signal processing module of the main control circuit board 15 completes the detection of the dust concentration signal, it can be sent to the host computer through the wireless transmission module 16.

[0025] Furthermore, if Figure 1 As shown, a 5V battery module is provided on the upper left side of the measuring device body 19 to supply power to the entire device.

[0026] Furthermore, if Figure 1 As shown, a fan 1 is provided on the left side of the measuring device body 19 , and the fan 1 is in direct contact with the inner space of the measuring device body 19 .

[0027] The working principle of the online real-time measurement system for dust concentration in cement plants provided in this embodiment is as follows:

[0028] After the measuring device body 19 is powered on, the reduction motor 9 rotates once every 1 minute according to the setting. After the reduction motor 9 rotates, the shafts on both sides are driven to rotate through the transmission shaft. After the shafts rotate, the left and right covers can be driven to open and close. When the covers on both sides are opened, the inside of the cement plant dust measuring device body is connected to the external environment. Driven by the fan 1, the air circulates, and then the dust content of the air inside the measuring device body 19 is the same as the external environment. When the left and right covers are closed, the light source 21 inside the wireless transmitting module 3 emits a light signal, and the light is backscattered by the cement plant dust, and part of the light signal is received by the optical fiber receiving module 4. At this time, the light signal is converted into an electrical signal by the photoelectric sensor 22 inside the optical fiber receiving module 4, and then processed by the signal conditioning circuit and the signal amplification circuit. It is transmitted to the main control circuit board 15 for processing. The measured dust concentration data is transmitted to the host computer through the wireless transmitting module 16, and then the data can be displayed, saved and analyzed. If the measured cement plant dust concentration is greater than the national health standard of 10mg / m 3 , the alarm 24 will issue an alarm indicating that the dust concentration exceeds the standard.

[0029] A schematic diagram of the backscattering of light through cement factory dust is shown below: Figure 4 As shown, a beam of light with an intensity of I 0 The light intensity is weakened after passing through the dust particles in the pipe, and the dust particles scatter it in all directions. The scattered light with an angle θ of 90° to 270° with the direction of the incident light is called backscattered light. Figure 4 In it, I is the backscattered light intensity, and r is the distance between the scattered light observation point and the scattering particles.

[0030] Embodiment 2

[0031] Based on the online real-time measurement system for cement plant dust concentration provided in Example 1, this embodiment provides an online real-time measurement method for cement plant dust concentration, including:

[0032] S1: Transmitting an optical signal to the cement plant through the optical fiber transmitting module, receiving the optical signal scattered by the dust particles in the internal space of the measuring device body through the optical fiber receiving module, and converting the optical signal into a voltage signal.

[0033] S2: Use the filter membrane method to measure the cement plant dust concentration of the internal environment of the simulation device, and measure the corresponding voltage values ​​under different cement plant dust concentrations to determine the functional relationship between the cement plant dust concentration and the voltage value.

[0034] S3: Based on the functional relationship between the dust concentration and the voltage value in the cement plant, the dust concentration in the cement plant is calculated according to the voltage signal through the signal processing module in the main control circuit board.

[0035] According to the cement plant dust backscattering theory, the cement plant dust concentration is linearly related to the backscattered light intensity. However, it is impossible to obtain the exact description equation of the curve, nor is it possible to calculate the measured concentration value. By consulting the data in detail, the cement plant dust concentration in the simulated device environment can be measured using the high-accuracy filter membrane method, and then the instrument can be used to record the measured value at this moment, and the cement plant dust concentration in different environments can be measured multiple times.

[0036] The working principle of the filter mass method is to use a vacuum pump to absorb a certain volume of dusty air at the measurement location. When it passes through the filter membrane of the sampler, the dust in the air is retained on the filter membrane. According to the filter membrane increment after use and the total air extraction volume, the concentration of air dust can be solved:

[0037]

[0038] Where: C is the dust concentration in the air, unit: mg / m 3 ; W 2 is the mass of the filter membrane after sampling, unit: mg; W 1 is the mass of the filter membrane before sampling, unit: mg; t is the sampling time, unit: min; Q is the sampling flow rate, unit: l / min; P is the atmospheric pressure under standard conditions, unit: 1.0313×105Pa; P 1 is the pressure of dusty air, unit: Pa; T is the absolute temperature under standard conditions, unit: 293K; T 1 It is the absolute temperature of dusty air, unit: K.

[0039] By measuring the dust concentration of cement plants in different environments by the filter mass method, the calibration value of dust concentration can be obtained. This detection instrument can measure the measured voltage value under different concentrations, thereby obtaining the functional relationship between the measured voltage value and the dust concentration. There is a linear relationship between dust concentration and voltage signal. When the dust concentration in the cement plant is high, the voltage signal is large, and when the dust concentration in the cement plant is low, the voltage signal is small.

[0040] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0041] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. An online real-time measurement system for dust concentration in cement plants, characterized in that: include: A measuring device body, a main control box, an optical fiber transmitting module and an optical fiber receiving module, wherein the main control box is arranged on the measuring device body, a main control circuit board is arranged in the main control box, and the optical fiber transmitting module and the optical fiber receiving module are arranged below the main control box; The optical fiber transmitting module is used to transmit an optical signal to the internal space of the measuring device body, and the optical fiber receiving module is used to receive the optical signal scattered by the dust particles in the internal space of the measuring device body; the environment of the internal space of the measuring device body is consistent with the environment of the cement plant; the optical fiber receiving module converts the received optical signal into a voltage signal and transmits it to the main control circuit board in the main control box; the main control circuit board calculates the dust concentration in the cement plant based on the obtained voltage signal.

2. The on-line real-time measurement system for dust concentration in cement plants according to claim 1, characterized in that: The main control box is fixed on the measuring device body through a fixing block.

3. The on-line real-time measurement system for dust concentration in cement plants according to claim 1, characterized in that: The measuring device body is provided with an upper cover plate, a front cover plate, a left cover plate and a right cover plate.

4. The on-line real-time measurement system for dust concentration in cement plants according to claim 2, characterized in that: A reduction motor, a left rotating shaft and a right transmission shaft are provided at the bottom of the measuring device body; one end of the left rotating shaft is connected to the left end of the reduction motor, the other end of the left transmission shaft is connected to the rotating shaft of the left cover plate, one end of the right transmission shaft is connected to the right end of the reduction motor, and the other end of the right transmission shaft is connected to the rotating shaft of the right cover plate; The reduction motor drives the left rotating shaft and the right rotating shaft to rotate, thereby driving the rotating shaft of the left cover plate and the rotating shaft of the right cover plate to rotate.

5. The on-line real-time measurement system for dust concentration in cement plants according to claim 1, characterized in that: The main control box is also provided with a wireless transmission module, and the main control circuit board sends the calculated dust concentration to the host computer through the wireless transmission module.

6. The on-line real-time measurement system for dust concentration in cement plants according to claim 1, characterized in that: An alarm is also provided on the main body of the measuring device, and the alarm is connected to the main control circuit board. When the dust concentration exceeds a set threshold, the alarm sounds an alarm.

7. The on-line real-time measurement system for dust concentration in cement plants according to claim 1, characterized in that: The measuring device body is also provided with a battery module.

8. The on-line real-time measurement system for dust concentration in cement plants according to claim 1, characterized in that: The measuring device body is also provided with a fan.

9. A method for online real-time measurement of dust concentration in cement plants, characterized in that: The method is applied to the on-line real-time measurement system for dust concentration in cement plants according to any one of claims 1 to 8, and the method comprises: Transmitting an optical signal to the cement plant through an optical fiber transmitting module, receiving the optical signal scattered by dust particles in the internal space of the measuring device body through an optical fiber receiving module, and converting the optical signal into a voltage signal; The dust concentration of the cement plant in the internal environment of the simulation device was measured by the filter membrane method, and the voltage values ​​corresponding to different dust concentrations of the cement plant were measured to determine the functional relationship between the dust concentration of the cement plant and the voltage value. Based on the functional relationship between the dust concentration and the voltage value of the cement plant, the dust concentration in the cement plant is calculated according to the voltage signal by the signal processing module in the main control circuit board.

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