Desulfurizing absorption tower slurry density measurement calibration method and calibration device

Abstract

The invention provides a desulfurization absorption tower slurry density measurement calibration method and a calibration device.The method comprises the steps that slurry enters a slurry density measurement cylinder through a slurry inlet pipe, and when it is detected that slurry flows out of an overflow port and pressure values collected by two pressure sensors vertically arranged at the preset height of the outer side of the circumferential direction of the cylinder wall are detected, the pressure difference value is determined; determining the slurry density according to a liquid pressure calculation formula, and opening an emptying valve to empty the slurry in the measuring cylinder; the calibration liquid is poured into the slurry density measuring cylinder until a preset height is reached, and the density of the calibration liquid is determined according to pressure values collected by the two pressure sensors; comparing the measured density value of the calibration liquid with a standard density value to determine a density difference value, if the density difference value is smaller than a preset value, adding the density difference value and the slurry density to obtain a calibrated slurry density value, and if the density difference value is not smaller than the preset value, performing early warning. The technical problem of measurement inaccuracy of the slurry density measuring cylinder of the desulfurizing absorption tower in the prior art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of solution density measurement, and in particular to a desulfurization absorption tower slurry density measurement calibration method and calibration device. Background Art

[0002] The density of the slurry in the desulfurization absorption tower of a thermal power plant has a direct impact on the desulfurization effect. Too low density will increase the consumption of desulfurizers and may lead to poor desulfurization effects, while too high density may increase energy consumption and costs. However, the existing desulfurization absorption tower slurry density measuring cylinder is to draw the slurry into the measuring cylinder, and install a pressure transmitter on the upper and lower parts of the slurry measuring cylinder respectively. The distance between the two transmitters is fixed, and the pressure generated by the slurry column of a fixed height is measured, and then the liquid pressure is calculated, and the density of the slurry is determined by using the conversion principle between density, pressure and liquid level. However, it is not considered that the device may cause density measurement errors during measurement due to problems such as slurry material hanging on the wall, which will lead to poor desulfurization effects. Therefore, improving the measurement accuracy of desulfurization slurry density to adjust and control the slurry density is of great significance for improving desulfurization efficiency and reducing energy consumption. Summary of the invention

[0003] In order to overcome the problems existing in the related art, the present disclosure provides a virtual train coordinated control method, device, equipment and medium to solve the technical problem of inaccurate measurement of slurry density measuring tube of desulfurization absorption tower in the related art.

[0004] One or more embodiments of this specification provide a desulfurization absorption tower slurry density measurement calibration method, comprising the following steps:

[0005] Step 1, open the slurry inlet valve, the slurry enters the slurry density measuring cylinder from the slurry inlet pipe, when the overflow port is detected to have slurry flowing out, the pressure values ​​collected by two pressure sensors vertically arranged at a preset height outside the circumference of the cylinder wall are used to determine the pressure difference value, and the slurry density is determined according to the liquid pressure calculation formula, and the vent valve is opened to empty the slurry in the measuring cylinder;

[0006] Step 2, opening the calibration liquid inlet valve, allowing the calibration liquid to enter the slurry density measuring cylinder from the calibration liquid inlet pipe, flushing the cylinder, draining the calibration liquid, and refilling the slurry density measuring cylinder with calibration liquid until it reaches a preset height, and determining the density of the calibration liquid according to the pressure values ​​collected by the two pressure sensors, wherein the calibration liquid is a liquid of known density; and

[0007] Step 3, compare the measured density value of the calibration liquid with its standard density value to determine the density difference. If the density difference is less than the preset value, add the density difference to the slurry density to obtain the calibrated slurry density value. If the density difference is not less than the preset value, issue an early warning.

[0008] Furthermore, the density difference setting threshold is ±8-12Kg / m 3 .

[0009] Furthermore, the density difference is set at a threshold of ±10Kg / m 3 .

[0010] Furthermore, the method also includes the following steps: when the program control fails or the slurry density measurement is suspended if the density difference is not less than a preset value, the slurry density value obtained in the last calibration is fed back to the desulfurization absorption tower slurry system.

[0011] Furthermore, the calibration liquid is water.

[0012] Furthermore, the slurry density measurement calibration process is implemented through a preset program control program of the slurry density measurement system, including the control of each inlet and outlet valve, and the execution of steps 1 to 3.

[0013] One or more embodiments of the present specification provide a slurry density measuring device, comprising:

[0014] A measuring cylinder, which is provided with a liquid inlet and is connected to the desulfurization absorption tower and the calibration liquid supply end through a slurry inlet pipe and a calibration liquid inlet pipe respectively; the slurry inlet pipe is connected to the liquid inlet through a slurry inlet valve, and the calibration liquid inlet pipe is connected to the liquid inlet through the calibration liquid inlet valve;

[0015] The upper side of the measuring cylinder is connected to the recovery tank through an overflow pipe, and the bottom of the measuring cylinder is connected to the overflow pipe through a vent valve;

[0016] An upper pressure sensor and a lower pressure sensor are arranged at intervals along the length direction of the measuring tube on the inner wall of the peripheral side of the measuring tube, and the interval is h, and the two pressure sensors are communicatively connected with the slurry density measurement system.

[0017] Furthermore, the slurry inlet valve, calibration liquid inlet valve and vent valve are all electromagnetic valves, which are controlled by a slurry density measurement system.

[0018] The present invention provides a desulfurization absorption tower slurry density measurement calibration method and calibration device, which have the advantages that, considering that the slurry density measuring tube may cause density measurement errors during long-term use due to problems such as slurry material sticking to the wall, the measurement accuracy of the slurry density measuring tube is detected by using a calibration liquid of known density, and the density difference of the detected calibration liquid is used as a calibration value and added to the slurry density measurement result, so that the measurement result can be corrected and the density measurement accuracy of the slurry density measuring tube is improved, thereby ensuring the desulfurization efficiency and the quality of gypsum, thereby solving the technical problem of inaccurate measurement of the slurry density measuring tube of the desulfurization absorption tower in the related art. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate one or more embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this specification. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A flow chart of a desulfurization absorber slurry density measurement and calibration method provided for one or more embodiments of this specification; and

[0021] Figure 2 A schematic diagram of a slurry density measuring device provided for one or more embodiments of this specification. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical solutions in one or more embodiments of this specification, the technical solutions in one or more embodiments of this specification will be clearly and completely described below in conjunction with the drawings in one or more embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. Based on one or more embodiments of this specification, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0023] The present invention is described in detail below in conjunction with specific implementation methods and the accompanying drawings.

[0024] Method Embodiment

[0025] According to an embodiment of the present invention, a method for measuring and calibrating the density of a desulfurization absorption tower slurry is provided. Figure 1 As shown, it is a flow chart of the desulfurization absorption tower slurry density measurement and calibration method provided in this embodiment. According to the desulfurization absorption tower slurry density measurement and calibration method of the embodiment of the present invention, the steps include:

[0026] Step 1, open the slurry inlet valve, and the slurry enters the slurry density measuring cylinder from the slurry inlet pipe. When the overflow port is detected to have slurry flowing out, that is, the liquid level of the slurry in the slurry density measuring cylinder reaches a preset height, the pressure values ​​collected by two pressure sensors vertically arranged at a preset height outside the circumference of the cylinder wall are used to determine the pressure difference value, and the slurry density ρ1 is determined according to the liquid pressure calculation formula, and the drain valve is opened to drain the slurry in the measuring cylinder;

[0027] Step 2, open the calibration liquid inlet valve, the calibration liquid enters the slurry density measuring cylinder from the calibration liquid inlet pipe, flushes it, drains the calibration liquid, and refills the slurry density measuring cylinder with calibration liquid until it reaches a preset height, and determines the density of the calibration liquid based on the pressure values ​​collected by the two pressure sensors, wherein the calibration liquid is a liquid with known density (standard density), such as water, and the calibration liquid can be selected based on cost.

[0028] Step 3, compare the measured density value of the calibration liquid with its standard density value to determine the density difference ρ2. If the density difference is less than the preset value, add the density difference ρ2 to the slurry density ρ1 to obtain the calibrated slurry density value. If the density difference is not less than the preset value, issue an early warning.

[0029] The desulfurization absorption tower slurry density measurement calibration method of this embodiment takes into account that during the long-term use of the slurry density measuring tube, the slurry material may stick to the wall, which may lead to density measurement errors during measurement. Therefore, the measurement accuracy of the slurry density measuring tube is tested by using a calibration liquid of known density, and the density difference of the tested calibration liquid is used as a calibration value, which is accumulated to the slurry density measurement result, thereby realizing the correction of the measurement result and improving the density measurement accuracy of the slurry density measuring tube, thereby ensuring the desulfurization efficiency and the quality of gypsum, thereby solving the technical problem of inaccurate measurement of the slurry density measuring tube of the desulfurization absorption tower in the related art.

[0030] In this embodiment, the liquid density calculation formula is ρ=ΔP / (hg), where ΔP is the pressure difference measured by the two pressure sensors, h is the height difference between the two transmitters, and g is the gravitational acceleration, which is taken as 9.8;

[0031] In this embodiment, the slurry density measurement calibration process can be program-controlled based on the slurry density measurement system of Ruiwo DCS through a program-controlled program, including the control of each inlet and outlet valve, and the execution of steps 1 to 3.

[0032] In this embodiment, the density difference threshold is set to ±8-12Kg / m 3 The preferred density difference setting threshold is ±10Kg / m 3 .

[0033] In this embodiment, when the program control fails or the density difference is not less than the preset value, the desulfurization absorber slurry density measurement system will suspend the slurry density measurement and issue an alarm to notify the operating personnel to perform fault detection and troubleshooting and clean the slurry density measuring tube, thereby ensuring the effective implementation of the detection process. When the program control fails or the density difference is not less than the preset value and the slurry density measurement is suspended, the slurry density value obtained from the last calibration will be fed back to the desulfurization absorber slurry system to ensure the stable operation of the desulfurization absorber slurry system.

[0034] In a specific embodiment, the control system designs a set of logic that can perform online calibration on the desulfurization absorber slurry density measurement system through Ruiwo DCS logic configuration, and corrects the pressure sensor measurement results in real time to achieve accurate measurement and calculation. At the same time, the measurement system installation process is optimized, the accuracy and stability of the measuring instrument are improved, etc., to improve the accuracy of the desulfurization absorber slurry density measurement. Online calibration logic method: After the density measurement program control is completed, the density value has been recorded, and the measuring cylinder contains the calibration liquid. At this time, the system measures the density of the calibration liquid, which is compared with the actual density of the calibration liquid, and the difference is accumulated to the recorded density measurement result, thereby improving the measurement accuracy of the desulfurization absorber slurry density.

[0035] Device Embodiment

[0036] According to an embodiment of the present invention, a slurry density measuring device is provided, such as Figure 2 FIG. 1 is a schematic diagram of the structure of a slurry density measuring device provided in this embodiment. The slurry density measuring device according to the embodiment of the present invention comprises:

[0037] A measuring cylinder 1 is provided with a liquid inlet, and is connected to a desulfurization absorption tower 4 and a calibration liquid supply end 5 through a slurry inlet pipe 2 and a calibration liquid inlet pipe 3 respectively; the slurry inlet pipe 2 is connected to the liquid inlet through a slurry inlet valve 21, and the calibration liquid inlet 3 is connected to the liquid inlet through a calibration liquid inlet valve 31.

[0038] The upper side of the measuring cylinder 1 is connected to the recovery tank 7 through an overflow pipe 6, and the bottom of the measuring cylinder 1 is connected to the overflow pipe 6 through a vent valve 8.

[0039] An upper pressure sensor 11 and a lower pressure sensor 12 are arranged at intervals along the length direction of the measuring cylinder 1 on the inner wall of the circumference of the measuring cylinder 1, and the interval is h. The two pressure sensors are communicatively connected with the slurry density measurement system.

[0040] In this embodiment, the specific measurement process is as follows:

[0041] Step 1: When the slurry density measurement system is programmed and started, the vent valve 8 is opened, the flushing water in the measuring tube 1 is drained, and then the slurry discharge valve is closed;

[0042] Step 2: Open the slurry inlet valve 21, and close the slurry inlet valve 21 after the slurry to be measured enters the measuring tube 1 and reaches a preset height, and let it stand for a period of time, which may be 20-30 seconds;

[0043] Step 3: The slurry density measurement system collects the pressure values ​​of the upper and lower pressure sensors and calculates and determines the slurry density value, controls the vent valve 8 to open, and discharges the slurry in the measuring cylinder 1;

[0044] Step 4: Open the calibration liquid inlet valve 31, first allow the calibration liquid to enter the measuring tube 1 to clean the measuring tube 1, then open the calibration liquid inlet valve 31 again, and close the calibration liquid inlet valve 31 after the calibration liquid reaches a preset height;

[0045] Step 5: The slurry density measurement system collects the pressure values ​​of the upper and lower pressure sensors and calculates and determines them as the calibration liquid values, and compares them with the actual density of the calibration liquid to achieve program control.

[0046] In this embodiment, the slurry inlet valve 21, the calibration liquid inlet valve 31 and the drain valve 8 are all electromagnetic valves, which are controlled by the slurry density measurement system.

[0047] This embodiment realizes slurry density measurement and calibration through slurry density measurement with a simple structure. The structure is simple, and the arrangement of the pressure sensor is easy to replace.

[0048] Each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The device and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein by equivalents. These modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and the contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. A desulfurization absorption tower slurry density measurement calibration method, characterized in that: The following steps are involved: Step 1, open the slurry inlet valve, the slurry enters the slurry density measuring cylinder from the slurry inlet pipe, when the overflow port is detected to have slurry flowing out, the pressure values ​​collected by two pressure sensors vertically arranged at a preset height outside the circumference of the cylinder wall are used to determine the pressure difference value, and the slurry density is determined according to the liquid pressure calculation formula, and the vent valve is opened to empty the slurry in the measuring cylinder; Step 2, open the calibration liquid inlet valve, the calibration liquid enters the slurry density measuring cylinder through the calibration liquid inlet pipe, flushes it, drains the calibration liquid, refills the slurry density measuring cylinder with calibration liquid until it reaches a preset height, and determines the density of the calibration liquid according to the pressure values ​​collected by the two pressure sensors, wherein the calibration liquid is a liquid of known density; as well as Step 3, compare the measured density value of the calibration liquid with its standard density value to determine the density difference. If the density difference is less than the preset value, add the density difference to the slurry density to obtain the calibrated slurry density value. If the density difference is not less than the preset value, issue an early warning.

2. The desulfurization absorption tower slurry density measurement and calibration method according to claim 1, characterized in that: The density difference setting threshold is ±8-12Kg / m 3 .

3. The desulfurization absorption tower slurry density measurement and calibration method according to claim 2, characterized in that: The density difference setting threshold is ±10Kg / m 3 .

4. The desulfurization absorption tower slurry density measurement and calibration method according to claim 1, characterized in that: Also includes the steps: When the program control fails or the slurry density measurement is suspended if the density difference is not less than the preset value, the slurry density value obtained in the last calibration will be fed back to the desulfurization absorption tower slurry system.

5. The desulfurization absorption tower slurry density measurement and calibration method according to claim 1, characterized in that: The calibration liquid is water.

6. The desulfurization absorption tower slurry density measurement and calibration method according to any one of claims 1 to 5, characterized in that: The slurry density measurement calibration process is implemented through the preset program control program of the slurry density measurement system, including the control of each inlet and outlet valve, and the execution of steps 1 to 3.

7. A slurry density measuring device for realizing a slurry density measurement calibration method for a desulfurization absorption tower, characterized in that: include: A measuring cylinder, which is provided with a liquid inlet and is connected to the desulfurization absorption tower and the calibration liquid supply end through a slurry inlet pipe and a calibration liquid inlet pipe respectively; the slurry inlet pipe is connected to the liquid inlet through a slurry inlet valve, and the calibration liquid inlet pipe is connected to the liquid inlet through the calibration liquid inlet valve; The upper side of the measuring cylinder is connected to the recovery tank through an overflow pipe, and the bottom of the measuring cylinder is connected to the overflow pipe through a vent valve; An upper pressure sensor and a lower pressure sensor are arranged at intervals along the length direction of the measuring cylinder on the inner wall of the peripheral side of the measuring cylinder, and the interval is h, and the two pressure sensors are communicatively connected with the slurry density measurement system.

8. The slurry density measuring device according to claim 7, characterized in that: The slurry inlet valve, calibration liquid inlet valve and vent valve all adopt electromagnetic valves and are controlled by a slurry density measurement system.

Images